**2.9 Solutions to soil erosion**

The kind of soil, terrain, local climate, and appropriate agricultural practices such as crop rotation or tillage methods all play a role in the decision-making process for controlling soil erosion [41]. Analyzing the efficacy of implemented techniques and customizing them for different fields is crucial [42]. The key to success is early problem discovery and the selection of appropriate solutions based on the severity of the issue. In the early stages of soil erosion, for instance, replanting, growing cover crops, or mulching can be successful treatments because vegetation protects fields from harm brought on by water runoffs, rainfall, and wind. In severe cases, the effects can be lessened by terrace farming or check dams [43]. In order to stabilize the ground and slow down water streams, further soil erosion management techniques include contour cropping and perennial plantings with robust root systems [44].


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## Meet the editor

Riadh Marzouki is an associate professor in the Department of Chemistry, Faculty of Sciences, King Khalid University, Saudi Arabia, and an international cooperator in the Department of Chemistry, Faculty of Sciences, University of Sfax, Tunisia. He is also a researcher in the Laboratory of Materials and Crystallography, University of Tunis El-Manar, Tunisia. His research activities include investigating the synthesis, crystal structure,

electrical properties, and biological activities of new crystalline materials. He is the author and co-author of more than sixty scientific papers, four book chapters, and three books.

Contents

**Section 1**

**Section 2**

**Section 3**

*by Oles Lastivka*

*by Yohichi Kohzuki*

**Section 4**

Mechanism Approach *by Esonye Chizoo*

**Preface XI**

Alkaline Chemistry in Catalysis **1**

**Chapter 1 3**

Alkaline Chemistry in Biology **27**

**Chapter 2 29**

Alkaline Chemistry in Polymers and Composites **45**

**Chapter 3 47**

**Chapter 4 59**

Alkaline Chemistry in Crystallography **77**

**Chapter 5 79**

Enzymatic Saccharification of Canola Straw and Oat Hull Subjected

An Overview of Alkali Treatments of Hemp Fibres and Their Effects

*by Obiora Samuel Agu, Lope G. Tabil and Tim Dumonceaux*

on the Performance of Polymer Matrix Composites

and Choice of Factors That Affect Service Life

Structure and Properties of Alkaline Cement and Concrete

Study on Influence of a State of Dopants on Dislocation-Dopant

*by Tom Sunny and Kim L. Pickering*

Ions Interaction in Annealed Crystals

to Microwave-Assisted Alkali Pretreatment

Alkali Homogeneous Catalyzed Methyl Ester Synthesis from *Chrysophyllum albidum* Seed Oil: An Irreversible Consecutive

### Contents

#### **Chapter 6 95**

Correlation between Structure, Electrical, and Magnetic Properties of Some Alkali-Oxide Materials *by Amira Marzouki, Ameni Brahmia, Riadh Marzouki, Mosbah Jemmali, Ismat H. Ali and Mohamed Faouzi Zid*

Preface

The alkaline elements are found in different quantities in the layers of the Earth. They are usable and useful in everyday life in different forms, such as salt, complexes, composites, and so on. In addition, they are widely used in the manufacture of materials showing interesting physical properties (e.g., batteries) that can be applied in several fields, including catalysis, biology, energy, and

This book describes the methods of synthesis of some alkali materials and their applications. It consists of four sections: "Alkaline Chemistry in Catalysis", "Alkaline Chemistry in Biology", "Alkaline Chemistry in Polymers and Composites", and

Chapter 1 in section 1 investigates the successful application of NaOH catalyst and methanol for the synthesis of fatty acid methyl ester from the highly underutilized seed oil of *Chrysophyllum albidum*. The described approach used in this study is simpler than most highly complicated reversible consecutive mechanisms and promotes easy translation to the industrial scale. The seed oil of *C. albidum* is therefore a viable feedstock for biodiesel production and alternative source of petrodiesel

Chapter 2 in section 2 presents a study showing that microwave (MW)-assisted alkali pretreatment of canola straw and oat hull enhances the enzymatic digestibility of these substrates compared to alkali pretreatment alone. MW-assisted alkali pretreatment and alkali treatment methods were effective in disrupting the lignocellulose structure of the biomass by inducing changes in their chemical compositions. The MW-assisted alkali pretreatment of biomass increased the glucose yields upon enzymatic saccharification. Total glucose yield overall was greater with KOH pretreatment compared to pretreatment with NaOH in both feedstocks. Therefore, based on the results presented, MW-assisted alkali pretreatment is an efficient pretreatment method of canola straw or oat hull substrate for bioethanol

Chapter 3 in section 3 focuses on alkali treatments of hemp fibers (cellulose crystalline) and their effects on the performance of polymer matrix composites. Chapter 4 examines the influence of changes in proportions between Portland cement and slag content along with different quantities of alkali components on

Chapters 5 and 6 in section 4 discuss the effects of crystal structure and dopant

heat of hydration and hardening character of cement systems.

contents on the physical properties of different alkali materials.

others.

production.

"Alkaline Chemistry in Crystallography."

with its renewable characteristics and advantages.


*2.2. Facilitated Diffusion*

Transport of DHA occurs by facilitated diffusion, enabling transport along a concentration gradient. This gradient is maintained as DHA is reduced to ASC immediately after crossing the membrane [21,45–47]. DHA, but not ASC [48,49], is transported by facilitated diffusion through four of the 14 glucose transporters (GLUT 1–4), although with varying affinities and efficiencies [47–50]. In general, these transporters have 12 transmembrane domains and are approximately 500 amino acids-long [51]. The GLUT-transport of DHA is competitively inhibited by glucose, e.g., excess glucose in plasma or intestine will block the receptor-binding site and, subsequently, decrease GLUT-facilitated DHA transport [21,47,48]. This association is also seen for DHA absorption to some specific cell types, whereas in others, glucose has less or even no significant effect on DHA absorption (*i.e.*, the luminal surface of absorptive gut epithelium and in tubular cells in the kidney) [21,35,47,52,53].

The distribution and transport properties vary among the different GLUTs. Thus, GLUT1 is expressed in a broad variety of cells throughout the body [48,51]; GLUT2 is primarily expressed in liver, spleen and the basolateral membrane of intestinal and renal epithelial cells [50,51]; GLUT3 is found particularly in the brain and in neurons [48,51] and GLUT4 in skeletal and cardiac muscle cells, as well as in adipose tissues [47,51].


$$P = \frac{\bullet}{m} \sum\_{i}^{m} \left[ \nabla\_{\mathbf{x}\_{i}, \mathbf{y}\_{i}'} D\left(\mathbf{x}\_{i}, \mathbf{y}\_{i}'\right)^{i} \right]^{2} \tag{12}$$

here, *D*(∗) represents the output of the D; L is the binary cross entropy, defined as:

$$\mathcal{L} = -[k \log(s) + (1 - k) \log(1 - s)]\tag{13}$$

Based on this loss function, the discriminator can achieve an output of 1 when the input is {*xi*, *yi*} and an output of 0 when the input is 4 *xi*, *y i* 5 , and then discriminates the wind speed sequence {*y*1, *y*2,... *yn*}.

The discriminator outputs a scalar of "0" or "1." The scalar of "0" or "1" has two purposes: (1) It can influence and then adjust the weights of the neural network in the discriminator and maximize Equation (14) through a backpropagation algorithm. (2) It can be passed to the generator to assist the PSO algorithm to find the optimal hyperparameters of the OBLS and then calculate the value of the fitness function *Fc*, which is defined as follows:

$$F\_{\mathbb{C}} = \frac{1}{n} \sum\_{i=1}^{n} D(G(\mathbf{x}(n))) \tag{14}$$

where *G*(∗) represents the output of the generator.

#### *2.5. Prediction Steps of the Proposed HGANN Model*

We propose the HGANN model for ultra-short-term wind speed prediction. The flow chart of the prediction process of the proposed model is shown in Figure 3. CEEMDAN is used to decompose the raw wind speed data {*x*1, *x*2,... *xn*} into multiple modes *IMFj*(*n*). These *IMFj*(*n*) are separately sent into the generator (OBLS) of HGANN to obtain virtual samples 4 *y* 1, *y* 2,... *y n* 5 . The discriminator (WGAN) takes 4 *xi*, *y i* 5 or {*xi*, *yi*} as input and then outputs scalars "1" or "0." The scalars "1" or "0" are passed to the generator (OBLS) and the discriminator (WGAN) to participate in iterative model updates. Through the continuous iterative update, OBLS obtains the optimal value of {*NF*, *NW*, *NE*}. The final wind speed forecasting values {*y*1, *y*2,... *yn*} can be obtained by stacking all forecast values.

**Figure 3.** Flowchart of the proposed HGANN model prediction procedure.

#### **3. Case Analysis**

#### *3.1. Data Description*

To demonstrate the applicability of the proposed model in different locations, we used datasets from the 50Hertz wind farm in Germany and the Mahuangshan wind farm in China [26]: HER and MHS, respectively. The HER datasets are freely available at http://www.netztransparenz.de/ (accessed on 5 October 2021). Both data sets are recorded for one year and wind speeds are measured in 15 min intervals. We selected wind speed series from both HER and MHS datasets for March, June, September, and December, representing spring, summer, autumn, and winter, respectively. Experiments using the four wind speed series of spring, summer, autumn, and winter can verify the applicability of our model at different periods. Each series contains 2880 samples. Table 1 shows information on the selected wind speed data for spring, summer, autumn, and winter.

**Table 1.** Seasonal statistics of the wind speed data.

In our experiments, the first 80% of the wind speed sequence was used as the training set, and the rest was used as the test set for ultra-short-term wind prediction. Table 1 displays the information of the four datasets. The experiments were implemented in MATLAB R2021b on a 64-bit personal computer with Intel(R) core i5-9300 CPU/16.00 GB RAM.

#### *3.2. Evaluation Index*

To comprehensively evaluate the prediction performance of HGANN, four evaluate indicators were given. MAE can accurately reflect the average value of the absolute error. MAPE divides the absolute error by the corresponding actual value. RMSE represents the sample standard deviation between the predicted value and the actual observation value, which has a very sensitive reflection and can reflect the accuracy of the prediction well. SSE represents the total error of the model. Their definitions are as follows:

$$MAE = \frac{1}{N} \sum\_{i=1}^{N} |y\_i - \hat{y}\_i| \tag{15}$$

$$MAPE = \frac{1}{N} \sum\_{i=1}^{N} \left| \frac{y\_i - \mathcal{Y}\_i}{y\_i} \right| \tag{16}$$

$$RMSE = \sqrt{\frac{1}{N} \sum\_{i=1}^{N} (y\_i - \hat{y}\_i)^2} \tag{17}$$

$$SSE = \sum\_{j=1}^{n} (y\_i - \hat{y}\_i)^2 \tag{18}$$

where *y*ˆ*i* is the predicted value and *yi* is the actual value.

#### *3.3. Comparable Methods*

To verify the prediction performance of the proposed HGANN, it was compared with 10 advanced predictive models, involving PSO-ANFIS [34], VMD-GA-BP [35], EEMD-GPR-LSTM [36], EMD-ISSA-LSTM [37], MWS-CE-ENN [20], CNN [38], WGAN [39], BLS [31], OBLS, and WGAN-OBLS. Table 2 lists the parameter settings of six comparison methods. BLS, WGAN, PSO-BLS, and PSO-WGAN-OBLS are the same as those of HAGNN to perform the ablation experiment for HAGNN.

**Table 2.** Parameter settings of the models.

In Table 2, *itermax* is the iterative number; *ep* is the number of network iterations; *np* is population size; *c*1 and *c*2 are personal and global learning coefficients, respectively; *nr*, *nv*, *ni*, and *no* are the number of rules, variables, input nodes, and output nodes, respectively; *k* is the decomposition number of VMD/EEMD; *nbi* is the number of the ith hidden nodes; *lr* is the learning rate of the network; *pr* is the training requirement accuracy; *nstd* is the noise standard deviation in ICEEMDAN/CEEMDAN; *ve* is the early warning value; *pd* and *ps* are the proportion of discoverers and sparrows aware of danger, respectively; and ˘ is the regularization parameter for ridge regression.

#### *3.4. Experimental Results*

#### (1) Experiment I: Comparison Between Different Forecasting Methods

We experimentally verified the effectiveness and advancement of the proposed HGANN by comparing it with PSO-ANFIS, VMD-GA-BP, EEMD-GPR-LSTM, MWS-CE-ENN, and EMD-ISSA-LSTM. Considering that wind data characteristics show strong seasonality, experiments were conducted using wind series from multiple seasons to further validate the predictive performance of the model. We chose the HER and MHS datasets for March, June, September, and December for this experiment. The training and testing processes of each of the compared models were repeated 10 times. The experimental results of the different datasets are presented in Tables 3 and 4, where the first-best predictions are highlighted. Figure 4 depicts the wind speed prediction results of the proposed model for the HER dataset.

**Table 3.** Forecast results of different models for the HER data.

**Table 3.** *Cont.*

**Table 4.** Forecast results of different models for the MHS data.

**Figure 4.** Forecasting results of HER wind speed data sets: (**a**) experiment results of spring wind speed sequences; (**b**) experiment results of summer wind speed sequences; (**c**) experiment results of autumn wind speed sequences; (**d**) experiment results of winter wind speed sequences.

Interestingly, it can be seen from Tables 3 and 4 that the proposed HGANN had the best prediction performance for each of the RMSE, SSE, MAPE, and MAE indicators on four datasets among all models. Wind speed forecasts at different times or at different locations may yield different results. Notably, our model achieved promising predictive results on both the geographically distinct German dataset HER and the Chinese dataset MHS. Furthermore, our model showed competitive prediction performance for wind series in different seasons. This indicates that our model can be extended to more general environments for wind speed prediction.

The abscissa and ordinate in Figure 4 represent the actual wind speed and the predicted wind speed, respectively; the blue line indicates that the predicted value is equal to the actual value. The ordinate of the green point is the predicted value, so the fit of the green point to the straight line reflects the accuracy of the prediction. As can be seen from Figure 4, the green points are very close to the blue line, which indicates that our model can predict wind speed effectively.

(2) Experiment II: Multi-Step Prediction Experiment

Multi-step forecasting can be built based on single-step forecasting. Compared to singlestep forecasting, multi-step forecasting is more practical for power systems. Therefore, in wind speed prediction, multi-step prediction is of high practical value. The experiment aimed to demonstrate the predictive performance of the HGANN model in multi-step forecasting. We selected 2880 samples from 23 August to 22 September from the HER dataset for the one-step, two-step, and three-step experiments. Performance metrics involved RMSE, SSE, MAPE, and MAE. Benchmark models covered PSO-ANFIS, VMD-GA-BP, EEMD-GPR-LSTM, MWS-CE-ENN, and EMD-ISSA-LSTM. The training and testing processes of each model were repeated 10 times. The experimental results of the proposed model and the benchmark models are shown in Table 5.

**Table 5.** Multi-step prediction results for 15 min wind speed.

From Table 5, it can be seen that the one-step, two-step, and three-step prediction results of the proposed HGANN model provided lower RMSE, SSE, MAPE, and MAE values than those of the benchmark models. For instance, the proposed HGANN provided 0.0091 (one-step), 0.0136 (two-step), and 0.0178 (three-step) on RMSE, compared with EMD-ISSA-LSTM, which provided the predictive results of 0.0109 (one-step), 0.0139 (two-step), and 0.0183 (three-step). Furthermore, we also provide clear visual results of multi-step predictions for the six models in Figure 5. The results from Table 5 and Figure 5 indicate that the proposed HGANN model had the best robustness and the highest wind speed prediction accuracy among all compared models.

**Figure 5.** Multi-step forecasting experiments under RMSE, SSE, MAPE, and MAE indicators: (**a**) experiment results on the RMSE indicator; (**b**) experiment results on the SSE indicator; (**c**) experiment results on the MAPE indicator; (**d**) experiment results on the MAE indicator.

(3) Experiment III: Ablation Experiment Between Single Models and Hybrid Models.

To verify the rationality of the proposed HGANN model, it was compared with WGAN-OBLS, OBLS, WGAN, BLS, and CNN on the HER dataset. The generator of HGANN is OBLS and its discriminator is the discriminator of WGAN. To emphasize the effectiveness of OBLS, it was compared with the generator of WGAN, namely, CNN. Similarly, all compared models were repeatedly trained and tested 10 times. In the HER dataset, 2880 data from 23 August to 22 September were selected for this experiment. The experimental results are shown in Table 6, where the first-best predictions are highlighted with dark gray backgrounds. The forecast results for 22 September 2019 are plotted in Figure 6, which also shows the forecast errors in superimposed shades.

**Table 6.** Forecasting performances of the proposed model and reference models.

Figure 6 shows that among all the compared models, our proposed model had the best curve fitting and the smallest predicted error. The suggested model consistently outperformed WGAN-OBLS, PSO-BLS, WGAN, OBLS, CNN, and BLS, as shown in Table 6. This further demonstrates the advantages of our proposed model, as it combines CEEMDAN, OBLS, and WGAN.

**Figure 6.** Forecasting results in HER dataset (22 September 2019).

Furthermore, first, compared with WGAN-OBLS without CEEMDAN, the proposed model had better predictive performance due to its covering CEEMADN and WGAN-OBLS, thus showing the effectiveness of CEEMDAN. Second, compared with WGAN or OBLS, WGAN-OBLS provided better predictive performance due to combing OBLS and WGAN, thus showing the effectiveness of OBLS and WGAN in WGAN-OBLS. Third, compared with BLS, OBLS provided better predictive performance due to using the improved PSO, thus showing the effectiveness of PSO in OBLS. Fourth, OBLS had better predictive results compared to the generator of WGAN, namely, CNN. This demonstrates the advantage of OBLS over CNN as a generator. This may be due to the flexible structure and better error convergence of OBLS.

#### **4. Discussion**

Our model was compared with five advanced models to evaluate its performance and advantages in various wind sequence experiments. Experimental results show that the proposed model had better predictive performance. The reasons behind this fact are given as follows.

First, the wind speed data were one-year data from wind farms in Germany and China, which cover complex fluctuation characteristics. Therefore, our HGANN model uses CEEMDAN to smoothen the volatility of the data and improve the predictive performance.

Second, HGANN uses OBLS as the generator to provide a special shallow broad incremental learning network structure, which can not only be beneficial for improving prediction accuracy for one-dimensional wind speed prediction compared to CNN but also greatly decrease computational cost using pseudo-inverse operations to determine the network weights instead of using convolution operations.

Third, in our HGANN model, the proposed OBLS uses an improved PSO to optimize the hyper-parameters of its network, which can search in a wider range and obtain the optimal parameters over BLS. Therefore, OBLS has better generalization ability than BLS.

Finally, HGANN can better extract the deeper features of wind speed data by playing a minimum–maximum game between the generator and discriminator for wind speed prediction.

#### **5. Conclusions**

Although existing various hybrid predictive models have provided competitive performance in ultra-short-term wind speed prediction, they still need to be further improvedfor instance, how to effectively reduce the computational cost of hybrid predictive models, and how to effectively deal with the multicollinearity problem of the hybrid forecasting model based on weighted strategy, which leads to the problem of reduced forecasting accuracy. To enhance the predictive power and decrease the computational cost, this paper proposes the HGANN model for ultra-short-term wind speed forecasting. HGANN is a generative adversarial network in which the generator and discriminator play against each other to obtain wind speed predictions with high accuracy. In HGANN, we developed OBLS and the convolutional structures as the generator and the discriminator, respectively, which enables them to obtain effective synergies to improve predictive performance. Particularly, OBLS involves a special shallow broad incremental learning network structure, which can effectively deal with one-dimensional wind speed data. Furthermore, the shallow network structure of OBLS can also significantly decrease computational cost via using pseudo-inverse operations rather than convolution operations. In addition, the proposed OBLS applies an improved PSO to obtain the optimal network hyper-parameters. CEEMDAN performs noise reduction and decomposition of the wind data. Via the above rational combination, the proposed HGANN provides high predictive accuracy and generalization ability with low computational cost in ultra-short-term wind speed prediction. The experimental results indicate the above fact. For instance, the RMSE predictive errors of the proposed model were 29.35%, 49.22%, 38.09%, and 30.10% compared to the four state-of-art predictive models PSO-ANFIS, VMD-GA-BP, EEMD-GPR-LSTM, and MWS-CE-ENN on the spring wind data of the HER dataset, respectively. In the future, we plan to use parallel computing to speed up the process of PSO optimization of BLS during training. Furthermore, the proposed HGANN will be extended to a wider range of applications, such as financial time-series forecasting, electricity-load forecasting, traffic forecasting, etc.

**Author Contributions:** Conceptualization, Q.W. and L.H.; methodology, Q.W.; software, J.H.; validation, Q.W., J.H. and L.H.; formal analysis, L.H.; investigation, Q.W. and Q.L.; resources, J.H.; data curation, Q.W. and Q.L.; writing—original draft preparation, L.H.; writing—review and editing, L.C. and Y.L.; visualization, Q.W.; supervision, P.X.L.; project administration, P.X.L.; funding acquisition, C.L. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work was supported in part by the National Natural Science Foundation of China under grants 62173176 and 61863028, and in part by the Science and Technology Department of Jiangxi Province of China under grant 20204ABC03A39.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.

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#### **References**

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The residents' aims could be about greater individual tenant choice or about developing a better large-scale, collective community response. There are also social and governance considerations, inasmuch as such systems involve empowering the residents in matters relating to their own choice of power and energy systems, as well as the control, maintenance and replacement responsibilities for these services. This therefore would include the residents' own individual fuel consumption, but also their collective control over installation, maintenance and refurbishment of the services providing their heating.

#### Financing community-led regeneration

The case studies presented here, as well as the experience of other estate residents across London, have shown how the demolition of housing can be stopped through the use of some of the planning tools explained here as well as strong and sustained campaigning. Now these successful groups are facing the challenge of leading the regeneration of their neighbourhoods, or of having genuine decision-making power in the regeneration process. When planning for any kind of regeneration (not just community-led), one of the key challenges is how to pay for it. For this reason, we decided to include the topic 'financing community-led regeneration' as one of the discussions in the final workshop. This focused on the available funding schemes and on other sources of funding, such as using the existing resources (land, buildings and potential for solar energy generation) of the neighbourhood.

An important topic that emerged in the discussions was the financial viability of refurbishment vs demolition. Such alternatives need to be appraised, particularly the issue of the cost of refurbishment that would have to be borne by leaseholders. In the case of Cressingham Gardens, the council estimated a very high cost for refurbishment (around £14m–£16m). The residents contested this figure and engaged a quantity surveyor who estimated a cost of £7 million, half of the council's figure. After this the council lowered their estimate to £9.4 million.10 This situation showed the importance of residents employing their own quantity surveyor as, without such professional inputs, they would have not been able to fight for the refurbishment case.

The remaining part of the discussion focused on sources of funding – in particular, how residents can access funding when giving notice for the Right to Manage11 and the Right to Transfer,12 when putting together a People's Plan, and when bringing council decisions to Judicial Review. There is support from central government for communities who wish to apply for the Right to Manage and the Right to Transfer. For the former, it is important to contact the National Federation of Tenant Management Organisations (NFTMO), which can provide support and advice on funding sources, and on recommending lawyers to put together a Tenant Management Organisation (TMO) (or Resident Management Organisation, as Cressingham Gardens residents call it). In the case of Cressingham Gardens, the NFTMO recommended a lawyer to them to set up their Resident Management Organisation; the council paid the lawyer's fees. Once the Right to Manage takes place, the TMO gets an allowance from the local authority to manage repairs and maintenance.

For the People's Plan, Cressingham Gardens used different sources of funding to pay for an architect (a former resident of the estate) and other professional consultants to support them in different parts of the People's Plan. They also used internal expertise, as there were highly qualified residents who dedicated a lot of time and effort to the People's Plan. This includes two chapters dealing with finance. Chapter 7 explains 'Five funding structures and their implication' and explores different options, varying from Lambeth developing the People's Plan to full community ownership, with some options in between that would require partnership between the local authority and the community. Chapter 8 explains different 'Funding sources' and provides a detailed account of different funding options and financial instruments that could be used to fund the People's Plan.13 The plan also considers other forms of generating income and the possibility of adding more housing. This includes the use of garages for building more homes and the production of energy with solar panels.

For Judicial Reviews, low-income tenants can access legal aid. For further information on this, see chapter 11, 'Using the law and challenging redevelopment through the courts'. Here the funding options are discussed, as are the differences between bringing a council decision to Judicial Review by an individual or by a community.

Finally, another key point derived from the Cressingham Gardens experience was the importance of a productive collaboration between tenants and leaseholders. In particular, because they had different rights, their access to information and to funding could also be different.

#### Knowledge exchange

Grassroots community groups have usually had years of coping with a range of issues at the local level. A form of embedded knowledge of lived experience has consequently developed which is valuable and needs to be recognised. At the same time, groups have needs for both further skills and spaces for up-skilling people within their groups in order to develop their own solutions to the urban problems they confront. While skills improvement can be offered by external individuals and organisations, such as academic or engaged practitioners, and can include technical subjects, there is also a need for more general information and communications. Making this more widely available would enable groups to be better informed, and to feel involved in the decisions being made in local authorities or at London level, for example.

Underpinning this issue of information and skills improvement for empowerment is the question of power, which has to be shifted. Consultation structures used in the past have repeatedly failed communities, which have become accustomed to failure and being lied to. The sharing of knowledge has to be accompanied by a shift in power relations. As the saying goes: 'Don't do it to me, do it with me'. For example, some places have experienced repeated waves of regeneration investment, starting in the 1980s with Estate Action, Housing Action Trusts, City Action Task Forces and City Challenge and followed, more recently in the 1990s, by the Single Regeneration Budgets (SRB), Estate Renewal Challenge Fund and New Deal for Communities (NDC). The outcomes, in some cases, have been very sparse in terms of local, surviving institutions. Not very much has been left of that investment apart from a sense of long-term failure, disempowerment, lies and acrimony, which has led to embedded civic disenchantment, even trauma.

There is a sense, in some places, that the regeneration programmes had been hijacked, and there remain serious capital investment problems to this day that need to be addressed. These places may be characterised by resident disengagement, linked to lack of trust, which needs to be rebuilt, within and between local groups and other organisations, such as housing associations or the local authority. Thus the displacement that accompanies regeneration can be a displacement both of people and of local institutions and existing social relations.14

For any knowledge exchange, engagement or skills improvement process, people must be willing to gather in a room. Yet it can be hard to achieve this. Not only is there the long-term disengagement to deal with, but in some cases a transitory population has also undermined knowledge and engagement. At the same time there may have been area stigmatisation,15 conflicts and the need to deal with a range of competing priorities.

As a result of the Right to Buy, the diversity of resident tenures increased. More people live now in private rented or housing association properties, and there are also misconceptions about the lived experiences of the different tenured households. All these factors have contributed to a fragmentation of both knowledge and political networks of community organisation.

Disengagement or disenchantment with local political processes are factors that have impacted on knowledge exchanges at a local level. These have been accompanied – and sometimes exacerbated – by cultural differences, especially in areas or estates which are not homogenous in terms of class, incomes, ethnicity or even tenures. These differences must be acknowledged as part of the training and knowledge dissemination as a way to bring people from one estate, or even from different estates, together at a local level. The exchange and empowerment which can lead to greater leadership by community groups can be supported topdown through state interventions, as well as bottom-up. Grassroots communities have solutions to urban problems, in part because of years of campaigning, but they require the tools, spaces and resources to develop these, along with access to the necessary information. However, given that people are being inundated with information, care must be taken with how information is used and the timescales of communication that are set. Often bursts of information come in a short period and then years pass. Alternatively, communities can be drip-fed with information, unrelated to what they themselves need or to their everyday lives.

Housing needs and regeneration pressures are also very urgent. When an individual family or community group needs information and access to knowledge, there is usually a serious time constraint. The people in need of housing do not have the time or skills to familiarise themselves with the complex world of community-led housing; instead they need institutions and resources to share the available information and knowledge. West Ken Gibbs Green Community Homes, as well as People's Empowerment Alliance for Custom House (PEACH), serve here as case studies, illustrating the importance of training communities to collect, utilise and have ownership of their own knowledge.

This can require broad political will, however, to support the building of community infrastructures and resident-led organisations, with resources for community organisers or tenant management workers. Tenant Management Organisations play a part in this ecology of community infrastructures, but these organisations are also complex in terms of governance and management. Other organisations able to play a role can be universities, who can support, through their researchers and students, the building up of community knowledge. This is a political vision of civic agency, based on the capacities of people and communities to solve problems and generate cultures: 'Power in the civic agency model is the "power to" not the "power over"'.16

The housing models themselves are flawed and need to be challenged. For example, the salaries paid to housing association chief executives, while they may be in line with other housing professionals, raise serious questions around how they are working and protecting council housing. This, in turn, raises the question of how can social housing be protected. Indeed, one can look beyond TMOs as forms of resident-led governance, recognising that every group is unique though there are commonalities in terms of knowledge support and resourcing. In shaping these challenges to current housing models, greater understanding needs to be shared about 'community-led' options at all levels of local governance. There is also a need to simplify community-led housing funds, processes and support structures. These might seem like utopian models, but there are good examples at grassroots level. At a wider scale, there is a need for more information and knowledge about the bigger picture – what shapes the housing market, the pressures of regeneration, the political decisions and institutions that make up the landscape and shape the dynamics to which residents are subject.

Learning from international experiences is also valuable. The example of Spain is important. Here the social housing conditions are very different to the UK, but there is a strong history of housing movements that are now moving into municipal power and trying to implement new forms of housing. A case in point is the municipal support for new housing policies around the human rights to housing17 and the new, municipal-led, co-operative housing projects in Barcelona.18 In Turkey an interesting aspect of the social housing challenge faced by residents attempting to gain more control of regeneration processes is the growing need for legal knowledge and professionals, to counter the increasing closure of democratic arenas for contestation.19

Six years ago the London Tenants Federation, Just Space, Southwark Notes Archive Group and Loretta Lees published the pamphlet *Staying Put*, a work that people still use and refer to. These forms of booklet, as information and communication tools, are a way of filtering information; they have a focus on support, disseminating successes as well as hope. The material needs to be presented in a way that is usable and, if in website form, easy to update. Other ways in which these important lived experiences can be shared can include the use of film, oral history recordings, photography and journals. These are all complementary forms, contributing to a community infrastructure of knowledge around housing and regeneration. Our attempt in this book is to build on, and to add to, this work.

## Community organising

The fourth topic discussed in the workshop examined the case studies of WKGGCH and PEACH where the importance of community organising to build and motivate strong campaigns, particularly long-lasting ones, needed to be sustained over time. Community organisers are people who dedicate time to bring residents together and help them to establish structures of governance. The workshop discussions focused on four areas: a) how to create a strong campaign, b) how to reach a wider community, c) how to influence decision-making and d) good governance and democratic accountability.

How to create a strong campaign

It is important to have a good point and purpose as the basis for the campaign. This purpose should be *inclusive* and *shared* at the same time: it should include marginalised groups but should also be tailored to different communities. At the same time, the campaign purpose should be shared by the different people who might live within a housing estate. For this reason it is important to establish shared values with clarity and transparency, while keeping in mind the main purpose of the campaign and not lose it. The discussion also focused on the importance of understanding who has decision-making powers and on building relationships with them.

#### How to reach a wider community

This is one of the key functions of a community organiser. They have to make the campaign as inclusive as possible among all the residents, not just those who engage with activities regularly. In doing so, the language used in the campaign should be accessible to everyone and alienation should be avoided, through meetings, home visiting and continually engaging with people. It is also useful to organise events and activities that can attract a wide diversity of residents, targeting different groups within the neighbourhood and building alliances with close (or not so close) neighbours.

#### How to influence decision-making

Patience is really important when seeking to influence decision-making. A strong campaign and support from other groups will also assist this end and, similarly to reaching a wider community, it is necessary to identify who the decision-makers are, in order to approach them and interact with them using easily understood language. It is also important to make these decision-makers feel comfortable with the objectives of the campaign (for which appropriate language is again important); a balance of hard contestation and positive engagement often works well. Social media can be a powerful tool to put pressure on local authorities, but it needs to be used very carefully and respectfully. It is important to challenge people in power, but with a non-offensive attitude.

#### Forms of good governance and democratic accountability

The last area discussed was the balance between informal and formal forms of governance. This is one of the conclusions of this book and a previous publication from this project.20 As the case studies have shown, the combination of formal and informal forms of governance allows flexibility; at the same time it provides decision-making structures and the necessary organisations to use certain formal tools. The discussion also addressed the importance of codifying rules and behaviour for good communication and relationships within the community. Another proposal was having 'custodians' or good governance in the neighbourhood.

The June workshop closed in a positive and optimistic environment, in which residents had discussed their strategies and achievements so far in proposing community-led regeneration plans. The event demonstrated the potential for residents to share experiences, both with others in a similar situation and with researchers working in collaboration with community groups.

#### Acknowledgements for Part III

This chapter is very much a collaborative effort emerging from the final sessions of the workshop held in June 2019. We would like to thank Richard Lee, Becky Turner, Elena Besussi, Frances Brill and Jonathan Rosenberg for helping us to plan and facilitate the four discussion topics during the workshop. We would also like to thank Loretta Lees, Adam Elliot-Cooper, Joe Penny, Elizabeth Knowles, who spoke about Alexandra Road Park Heritage Lottery Fund restoration, and the residents and community organisers who participated in the sessions – including those from WKGG, PEACH, Cressingham Gardens, Greater Carpenters Neighbourhood Forum, Alexandra and Ainsworth Estates, and WECH for their participation on the panel sessions. We would like to thank Just Space for co-organising the workshop with us and WKGGCH for hosting us in their community hall. We would also like to thank all participants for their contribution to the discussion and the workshops.

#### Notes

## Conclusions

After having explored the seven case studies and reviewed the strengths and limitations of the existing planning tools and frameworks for community-led regeneration, we have explained how the available planning tools can be used for opposing demolitions and proposing community-led plans. We have also identified what difficulties and limitations residents might find, and how these limitations can be overcome.

Planning frameworks such as neighbourhood planning have certain limitations on opposing local authorities' plans. This is because neighbourhood forums and areas need to be designated by the planning authority, and the Neighbourhood Plan needs to comply with other policy documents issued by the same local authority. Such frameworks also require time commitment, as the process from designation of the neighbourhood forum until the plan is brought into force is long. There are also questions on the implementation of the plan and the funding for implementing it.

From the case studies presented here, only one has submitted a Neighbourhood Plan. This occurred in a very particular condition, where the planning authority (London Legacy Development Corporation) was different from the borough (London Borough of Newham). Other tools, such as the Right to Transfer, have not been fully tested, since none of the cases where this legislation has been used have yet been completed. Two of the case studies presented here have given notice for the Right to Transfer, but only one of them, Cressingham Gardens, has been successful in being approved by the Secretary of State. This determination happened while this book was being written, so it is not yet possible to analyse how the transfer has taken place. Despite not being fully tested, the Right to Transfer, if and when confirmed by a Resident ballot, could save Cressingham Gardens from demolition and give residents control over the regeneration of their neighbourhood.

Despite these limitations, the case studies have thus demonstrated that the combination of these formal strategies with other forms of informal planning, activism and campaigning is very effective in opposing demolition and proposing alternative plans. Some of them have combined formal planning and legal tools with developing a non-statutory People's Plan that has brought together a residents' vision for the neighbourhood. The People's Plan, in combination with other strategies, has proved to be a very effective strategy. Its effectiveness lies in the flexibility it provides, and in the way that it can be put together in a relatively short time. In the case of Greater Carpenters Neighbourhood Forum, putting together a community plan (equivalent to a People's Plan) provided an opportunity for residents to put together a community vision; it served as a first step before committing to the neighbourhood planning route. From this case study, we conclude that putting together a community plan or a People's Plan can be a good first step for making the decision on whether neighbourhood planning is a good option or not. In the case of Cressingham Gardens Community, the People's Plan contributed to their success in getting approval by the Secretary of State for continuing with their Right to Transfer.

Since we started this project at the end of 2016, the situation of these housing estates and their residents has changed. In many cases, after years of campaigning, residents are succeeding in stopping the demolition of their homes and gaining a stronger say in their neighbourhood's future. In all cases the campaigns are still ongoing, and therefore it is not clear whether they will manage to achieve a community-led regeneration, but this remains a possibility for all the campaigns. Some of the campaigns examined in this report have already managed to complete a communityled regeneration. One such is the case of Walterton and Elgin Community Homes (WECH), which completed the transfer of housing from the local authority to a community-owned housing association in the early 1990s, and is now building new social housing on the rooftops of some of their blocks. Alexandra and Ainsworth Estates residents managed to get funding and to work in partnership with their local authority in refurbishing their park. Cressingham Gardens Community have succeeded in getting approval for both the Right to Manage and the Right to Transfer.

From the analysis of the case studies and the tools and strategies, we can divide the specific conclusions into the following three sections.

## A toolkit for different steps of the 'ladder of participation'

The tools that we have explained in this report provide different possibilities for communities participating in the decision-making process around the regeneration of their neighbourhoods.1 In her seminal paper 'A Ladder of Citizen Participation', Sherry Arnstein defined a ladder with eight degrees of participation (fig.C.1), with 'manipulation' at the bottom and 'citizen control' at the top.2

**Figure C.1** Cartoon by Rob Cowan from *Built Environment* 45, nos 1 and 2, 2019. © Alexandrine Press.

In many of the case studies explained here, the discontent felt by residents towards the council's approach to regeneration and/or the threat of seeing their homes demolished has led residents to seek control of the regeneration process of their homes. This happens particularly when the council does not listen to the residents and wants to continue with demolition. In those cases, residents seek control of their estate to prevent the demolition of their homes. This has resulted in campaigns aspiring to be at the very top of the ladder and using strategies such as giving notice for a Right to Transfer (as West Kensington and Gibbs Green or Cressingham Gardens residents have done).

However, citizens' control is not the only option to have a meaningful participation. Depending on each situation, and on the residents' intentions, other steps of the ladder can also work. The top three steps of the ladder, named by Arnstein as 'degrees of citizen power', should be the aspiration of every social housing regeneration scheme. These three steps are 'citizen control', 'delegated power' and 'partnership'. Many of the tools explained here can lead to these three levels of participation.

In any case, the minimum requirement for any regeneration scheme, in case the community is not willing to take a leading role, must be to run a lawful consultation (step 4 of the ladder). In England and Wales, the Principles of Fair Consultation, explained in chapter 11 of this book, set out very clearly what a lawful consultation must be. Residents must be given sufficient time and information to participate, and their responses to the consultations have to be heard and considered in the scheme (among other requirements). Any consultation that does not meet these principles can be challenged through a Judicial Review.

However, there are some consultation processes that, despite legally meeting the Principles of Fair Consultation, still produce discontent among residents and campaigners. The reason for this is because local authorities hold the power to run these consultation processes, and they can formulate the questions to get the responses they want. When this happens, the consultation is closer to the 'manipulation' step of the ladder.

#### Building capacity for community-led regeneration

The book has explored how the combination of strategies, the interaction between communities, the creation of networks and the access to support can make campaigns stronger in resisting demolition and proposing alternatives. The book has identified three particular situations, combination of facts, strategies and alliances that make campaigns stronger in resisting demolition.3

First, communities using a combination of formal organisations, such as neighbourhood forums or Community Land Trusts, along with informal organisation and campaigns, have a strong capacity to resist demolition and propose alternative plans, since they have the ability to engage both in formal planning strategies (within existing planning frameworks) and in informal strategies (such as demonstrating or occupying). The combination of these formal planning tools and informal strategies is the most effective way to resist demolition and propose alternative plans. Second, the creation of networks and the exchange of knowledge between campaigns going through similar situations can strengthen their campaigns. Resident groups learn from each other. When communities are successful using a particular strategy, this serves as precedent for other groups. Third, as some of the case studies have shown, the access to support from professionals (such as community organisers, planners, architects, lawyers and surveyors) and from researchers (through collaboration with universities) can strengthen campaigns and also build local knowledge of planning within the community.

### What is the impact of campaigning?

The research demonstrates that campaigning does have an impact. In those case studies fighting against demolition, the work has either been stopped or delayed. In addition to that, some of the case studies presented here, such as WECH or Alexandra and Ainsworth Estates, have managed then to lead, or to have an important role in, the regeneration of their neighbourhoods.

Housing activism implies long-lasting campaigns, which can be very tiring and energy-consuming for residents. The presence of community organisers and housing organisers, such as in the cases of People's Empowerment Alliance for Custom House (PEACH) or West Ken Gibbs Green Community Homes, is thus very important in keeping residents motivated and supported. Cases such as PEACH, which invested a large proportion of its Big Local funding into community organising, demonstrate the importance of community organising in bringing a community vision together, and in getting communities to have an important role in decision-making.

We would like to finish this book with a message of hope and optimism for campaigners. Since we started this research, some of the campaigns we have studied have made considerable achievements in their campaigns. While they are still in the process of achieving what Arnstein would define as 'degrees of citizen power', they are getting closer. Housing campaigners are starting to influence decision-making at a neighbourhood scale, at a local authority scale and, in the case of London, at a metropolitan scale through the consultation process on the Mayor of London's policy documents (see chapter 10).4 The achievements of these campaigns can motivate other activist groups to resist and fight for their rights, as well as provide for knowledge transfer between individual campaigns. In addition to this, the rise of activism, the increasing politicisation of estate resident communities, along with other housing groups and the prominent denouncing of situations of injustice, can play an important role in influencing, reversing or indeed finding alternative policies to the politics of austerity.

#### Notes

## Bibliography

Ajuntamiento de Barcelona. 2016. Barcelona Right to Housing Plan 2016–2025. https://habitatge. barcelona/en/strategy/right-to-housing-plan. Accessed 23 January 2020;

Ambrose, Peter and Stone, Julia. 2010. *Happiness, Heaven and Hell in Paddington: A Comparative Study of the Empowering Management Practices of WECH*. Brighton: University of Sussex.

Anson, Brian. 1981. *I'll Fight You for It: Behind the Struggle for Covent Garden, 1966*–*74*. London: Jonathan Cape.

Architects for Social Housing. https://architectsforsocialhousing.co.uk. Accessed 30 July 2019.

Architects for Social Housing. 2016. 'Feasibility Study Report: West Kensington and Gibbs Green Estates. New Homes and Improvements without Demolition'. https://architectsforsocialhousing. files.wordpress.com/2016/08/wkgg\_report\_rev3.pdf. Accessed 23 July 2019.

Arnstein, Sherry Phyllis. 1969. 'A Ladder of Citizen Participation', *Journal of the American Planning Association* 35(4): 216–24.

City Life / Vida Urbana. http://www.clvu.org. Accessed 1 August 2019.

Cressingham People's Plan. 2016. http://cressinghampeoplesplan.org.uk. Accessed 21 June 2016. Crowdjustice. https://www.crowdjustice.com. Accessed 16 October 2019.

freedom-information/foi-disclosure-log/foi-estate-regeneration-schemes-london. Accessed 16 July 2019.

Planning Advisory Group. 1965. *The Future of Development Plans*. HMSO: London.

## Index

Aarhus Convention and Aarhus claims 118 affordable housing 14, 99–101, 105–6 Alexandra and Ainsworth Estates 5, 9, 55–9, 139, 150, 153 alliances with other groups 134 Architects for Social Housing (ASH) 20, 47, 103, 131 Arnstein, Sherry 53, 64, 150–3 assemblage theory 6 Assets of Community Value 36, 88–90 Athens and Kincardine Gardens 13–14 Balfron Tower 57 ballots of residents 4, 12, 30–2, 39, 53, 65, 71, 74, 82–3, 87, 101, 105–8 advantages of 108 Barcelona 2, 144 Beirut 2 'Better Homes' programme 58, 103 Big Local funding 50, 153 Brimstone House 46 Buckley, Peter 119–20 campaigning 31–2, 41, 46–7, 63–4, 115, 123, 132–3, 145–6, 153–4 impact of 153 Canning Town 51–2 Capital and Counties Properties PLC (Capco) 19–22 Carpenters Estate 9, 85–6, 126, 128, 131, 134; *see also* Greater Carpenters Neighbourhood Forum, Carpenters Against Regeneration Plans (CARP) Civil Procedure Rules 118 Coin Street Community Builders 127 common assessment model 70 common law system 123 Commonhold and Leasehold Reform Act (2002) 66 community, sense of 13 community cohesion 17 community events 134 community facilities 14 community groups 101–2 Community Housing Fund 14 Community Infrastructure Levy (CIL) 82, 84 community involvement and participation 93–4 Community Land Trusts (CLTs) 53, 77, 152

community-led development 2–7, 9, 16, 22–4, 28, 37, 52, 61–2, 67, 77, 80–8, 94–103, 127–30, 134, 138, 144, 149 difficulties with 101–3 financing of 140–1 community management 121–2 community organising 145–7, 153 Community Ownership and Management of Assets programme 90 Community Right to Bid 88–90 Community Right to Build 82, 86–8 competitive tendering 13 complaints procedures 117 compulsory purchase 21 conservation-based approaches 13 consultation processes 81, 120–1, 152 core groups of campaigners 63–4 Core Strategies (before 2012) 83 costs caps 118–20 Court of Appeal 116 Covent Garden Community Association 126–7 Cressingham Gardens Community 5–6, 9, 21, 26–32, 63, 69–70, 75, 78, 90, 121, 126–8, 131, 134, 137–41, 149–52 crowdfunding 119–20, 130 Custom House 50–2, 131; *see also* People's Empowerment Alliance for Custom House debt write-offs 71, 73 decision-making power and procedures 2–3, 6, 17, 34, 53–4, 61, 108, 111, 121–3, 129, 140, 145–6 delegation of budgets and responsibility 66 demolition, opposition to 1–6, 9, 21–2, 26–8,

34, 41, 52, 61, 69, 72, 78, 83, 125, 127, 132–3, 137, 140, 149–53 density of housing 75 diagrams, use of 6 direct action 133–4 discounted fee arrangements 119 district heating 139

Earl's Court development 75–8 Edwards, Michael 126 empty property 42–4, 134 energy efficiency 59 engagement of communities 1 environmental issues 14, 97–8, 118 Equality Act (2010) 61, 120, 122 estate boundaries, definition of 107–8 Estate Management Board model 66 estate regeneration 95–6, 100–6, 121 good practice guide on 101–6 national strategy for 95–6 poor practice in 137 evidence-based documents 128

fairness 16, 120–1, 152 feminism 44 films 22 *Focus E15* 5–6, 9, 41–8, 132, 134 formal and informal procedures 146, 149, 152–3 Foxhill Estate 119–20 Freedom of Information (FOI) requests 31, 106–7 fuel poverty 138 fundraising 89–90, 129–30

Gibbs Green *see* West Ken Gibbs Green Community Homes Gilesmead Estate 139 governance 146 graphic design 133 Greater Carpenters Neighbourhood Forum (GCNF) 5–6, 9, 34–9, 84–6, 90, 137–8, 150 Greater London Authority (GLA) 4, 31–2, 72, 99, 102, 105–8, 122, 137 Greater London Council (GLC) 11 Grenfell Tower fire (2017) 69

heating systems 56–9, 138–40 Heritage Lottery Fund 9, 55–9 Heygate Estate 101, 129, 137 High Court 121 Hollamby, Edward 26 homelessness 13, 42–3 Housing Act (1985) 20, 65–5, 71, 121 Housing Act (1988) 11–12, 15 housing allocation grant (HAG) 13 Housing and Planning Act (1986) 66 Housing and Regeneration Act (2008) 20, 71 housing associations 9, 65, 73–4, 150 Housing Corporation 12–13 Housing (Rents and Subsidies) Act (1975) 66 Housing (Right to Manage) Regulations 66, 68 Housing Hubs 77, 88, 94, 101 human rights 138–9, 144

independent examiners 39, 81, 86 infill development 36, 87 informal actions, strategies and tools used in campaigning 125, 132 injunctions 116 international experience 144

Judicial Review (JR) 21, 27–8, 31, 61, 74, 78, 112–17, 120–3, 140–1, 152 potential impact of 122 procedure for 115–16 timing of 114–15

Just Space 2–4, 37, 97–9, 106, 122, 131, 138 Khan, Sadiq 137 knowledge transfer 21, 141–5, 153–4 'ladder of participation' (Arnstein) 53, 64–5, 150–2 Lambeth Council 27, 30, 75, 78, 121 leaseholders' rights 66 Leathermarket JMB 87–8 Lees, Loretta 2, 104, 129, 138 legal aid 118, 141 legal remedies 111–14 listed buildings 55–9 Local Management Agreements 66 Local Plans 36–9, 82–5 Localism Act (2011) 27–8, 61, 63, 80–90, 101, 128 Locality network 85, 90 London 1, 6, 62, 83, 94, 153; *see also* Mayor of London London Community Housing Fund 88 London County Council (LCC) 11 London Housing Strategy 93, 100–1 London Legacy Development Corporation (LLDC) 34–9, 84, 86, 149 London Plan 93, 96–9, 122 London Tenants Federation (LTF) 2, 99, 104, 129 maintenance of properties *see* repairs to and maintenance of properties Mayor of London 4, 14, 21, 31, 88, 98–100,

103–6, 122, 137, 153 media attention 46 Milan 2 mobilising people 132 mothers' groups 41–3 Myatts Field North 139 MyCommunity website 85

National Federation of Tenant Management Organisations (NFTMO) 30, 70, 141 natural justice 113 Neave Brown (architects) 55, 57 Neighbourhood Development Orders 86–8 neighbourhood forums (NFs) 35, 37, 81–5, 128, 149, 152; *see also* Greater Carpenters Neighbourhood Forum neighbourhood planning 34–9, 54, 80–7, 101, 128, 130, 150 neoliberalism 2 New London Architecture Awards for Housing 88 Newham 34, 36, 39, 41–6, 50–3, 86, 149 North British Housing Association (NBHA) 14 'no win no fee' arrangements 119 occupation of empty property, 'political' 43–4, 134 online campaigns 132–3 outreach work 12 ownership of properties, control over *see* Right

to Transfer

Paddington Churches Housing Association (PCHA) 12 Pankhurst, Sylvia 41, 44, 47 partnership working 53–4, 129 People's Empowerment Alliance for Custom House (PEACH) 5, 9, 50–4, 126–31, 137–8, 143, 153 People's Plans 27–30, 35, 39, 51–4, 61–2, 78, 84–5, 125–30, 140–1, 149–50 difficulties with 128–9 reasons for use of 130 plan-making processes 121–2 planning permission 87, 114 planning tools 1–6, 149 policing 17 power imbalances 74 'power to' and 'power over' 144 pre-action protocol letters 115 pressure, application of 133 privatisation of housing 74, 82 *pro bono* representation 119 procedural improprieties or defects 113 professional expertise 76–7 *propositional* as distinct from *oppositional* input 41, 77, 94 'protected characteristics' 120, 122 public authorities acting unlawfully 113 Public Sector Equality Duty (PSED) 99, 119–23 referenda *see* ballots refurbishment programmes 13, 26–7, 36, 55–8, 69, 73, 82, 84, 121, 129, 137, 140 regeneration processes 1–2, 5–6, 9, 15–16, 20–2, 32, 36, 51, 61, 63, 67, 72–6, 80, 87–8, 93–103, 111–13, 121–2, 140–3, 150–3 rehousing 129 repairs to and maintenance of properties 29–32, 69, 139 Resident Management Organisations (RMOs) 28, 30–1 residents' control 63–78, 139–40 Revolutionary Communist Group (RCG) 42–4 Right to Manage (RtM) 31–2, 61–7, 70–6, 140–1, 150 advice and support on 70

Right to Manage (RtM) companies 66 right to return 129 Right to Transfer (RtT) 15, 20–1, 24, 27–32, 61–7, 71–8, 127–31, 140–1, 149–52 Rosenberg, Jonathan 19, 21, 23 Save Cressingham 31 Skeffington Report (1969) 93 slum landlordism 11 social cleansing 42–4 social housing 1, 3, 9, 14–17, 44, 51, 55, 57, 67–74, 82–3, 90, 95–105, 127, 137–8, 144, 150 challenges faced by 138 Social Life (company) 26 social media 58–9, 133, 146 solar panels 139, 141 Southwark Notes Archive Group 2 Spain 144 *Staying Put* (pamphlet) 2, 129, 144 strategic plans 62 support for residents' groups, *technical* and *financial* 76–7, 85, 88, 90, 101, 130–1 Supreme Court of the United Kingdom 121 swapping homes 13 Sylvia's Corner 43–4 Tenant Management Organisations (TMOs) 64–70, 75, 77, 88, 143–4 Tenants Choice legislation 11–12, 15, 20–1, 65 tenure types, diversity of 73, 143 time constraints 64, 114–15, 143 toolkit use 4–7, 9–10 Turkey 144 University College, London (UCL) 34–7, 131 Walterton and Elgin Community Homes (WECH) 5, 9, 11–17, 19, 21, 65, 77, 133, 150, 153 Waltham Forest 77 West Ken Gibbs Green Community Homes (WKGGCH) 5–6, 9, 19–24, 63, 75–8, 126, 128, 131, 134, 137–8, 143, 152–3

Westminster City Council 11–13 workshops 3, 5, 102, 138


**8. Discussion**

Nowadays , there are several models for studying, predicting, and analyzing the power losses in the ferromagnetic cores of magnetic components. Usually, these models consider a series of parameters based on magnetic units and frequency to predict and calculate power losses. Figure 9 illustrates a comparison between core losses models depending several features.

**Figure 9.** Power core losses models' comparison depending on the size of the phenomena analyzed, kind of losses to calculate and ferromagnetic materials. Features of mathematical models, timedomain approximations, loss separation, and empirical methods are in color yellow, blue, pink, and purple, respectively.

Nevertheless, one main application of magnetic components is in power electronics, where the measurement units are electric, which in many cases cause inexactness while designing a magnetic element. A common idea in the literature is that in a magnetic component with high operating frequency, its losses and size will be lower; however, this is not always true. There are many factors involved (kind of material, core losses, copper losses, among others) to determine the integrity of this expression. Although the last years' power electronic researchers have been working hard to find and develop numerous techniques to achieve better performance from magnetic components, the way is still long. For instance, the future design of magnetic components should take advantage of all capabilities of the final application (support multiple input/outputs, multiple voltage/current domains, characterization of the material, losses' reduction, among others), with the option to work in parallel with switches at high frequency [12,176].

On the other hand, the industry of FEM software is more versatile each year; several applications and tools are added to these, improving accuracy, functionality, scenarios to apply it, and user friendly environments. Nonetheless, a common point is a lack of compatibility among those, limiting the use of platforms to validate and complement the final design. This lack of compatibility motivates users to know different packages to solve a unique problem.

This is translated into a monetary cost to purchase different licenses and increase computer resources. Therefore, to motivate and improve the FEM designs, in this authors opinion, a standard format type should be implemented in the following years between those kinds of software to take advantage of each characteristic and unify all FEM files.

In the literature, static or dynamic core losses models can be found, depending on the designer choice, the loses calculus could be as complex as the model chosen [177]. So, the model selection in function of the material and the requirements' application of a magnetic component's design process are fundamental to achieving an accurate core losses calculus.

Table 3 illustrates a comparison between power core losses models, ferromagnetic materials, and accuracy. It is essential to mention that ferrite is the start point to validate any power core losses model, so this is not listed. Nonetheless, to the best authors knowledge, not all models had been tested in all ferromagnetic materials, or those are not suitable to calculate their power core losses.

**Table 3.** Comparison between empiric core losses models. The sinusoidal and non-sinusoidal waveform are indicated with light yellow and light green, respectively.

Designers can use the information mentioned in Table 3 and Figure 9 to improve some of the power core loss models listed before or propose their model, always keeping in mind that any design parameter will be sacrificed to improve another one; magnetic components size will be reduced with frequency increment.

Due to the high energy consumption worldwide, renewable energy sources and energy efficiency have accelerated research in energy applications, conversion, transportation, and telecommunication [178].  Materials' demand as electric steel, iron, and cobalt will be exponential growth for 2026. Studies on the effect of magnetic materials in renewable energy have to be a priority to guarantee the supply chain, options for recycling, the footprint impact, the blueprint impact, and the socio-economical impact of their extraction [180,181].


**7.1 Scoring systems for discharge**

Discharge scoring systems may be used shortly before discharge to identify and record the psychological status of a patient. Modified Aldrete Scoring System (**Table 4**) is widely used to assess when patients from the post-anesthetic care unit are ready for discharge. Patients must score 9 out of 10 before discharge from the recovery room. In addition, the patient must be assisted by a responsible person at home and there must be no complications from surgery, such as bleeding or vomiting. It is no longer important to ensure that the patient is able to take fluids orally, or that before discharge at home, he or she has passed urine. However, if not able to move urine within 6–8 hours of discharge from the sedation unit, the patient must be instructed to contact the responsible practitioner.

#### **Table 4.**

*Modified Aldrete discharge scoring system (Total\* \*a score of 10 was required for discharge from the endoscopy/ recovery room.*


**1. Introduction**

Stress-induced cardiomyopathy is caused by intense emotional or physical stress leading to rapid and severe reversible cardiac dysfunction. This condition can occur following a variety of emotional stressors such as grief, fear, extreme anger, and surprise. On the other hand, many physical stressors (i.e., stroke, seizure or acute asthma) can also trigger the condition. Suspicion of stress cardiomyopathy is based on clinical symptoms, abnormal electrocardiogram (ECG), mildly elevated serum cardiac troponin, significantly elevated serum natriuretic peptide levels (BNP or NT-proBNP), and noninvasive cardiovascular imaging. Stressinduced cardiomyopathy symptoms following severe stress are often indistinguishable from a heart attack and may include: (1) chest pain, dyspnea, or both during stress period (often sudden and intense) [1]; (2) shortness of breath, (3) rapid or irregular heartbeat, (4) sweating and (5) dizziness [2]. The exact pathophysiology of stress-induced cardiomyopathy remains elusive, and several mechanisms may be involved (**Figure 1**).

Considering the causes of stress-induced cardiomyopathy, the exact cause of stress-induced cardiomyopathy is unclear. In patients without coronary heart disease, emotional stress can lead to severe, reversible left ventricular dysfunction. Although the mechanism of stress-induced cardiomyopathy is unclear, excessive sympathetic stimulation may be central to its etiology, perhaps involving excess catecholamines (**Figure 1**), but the link between the two is unclear. One possibility is ischemia due to epicardial coronary spasm; additionally increased sympathetic tone can lead to vasoconstriction in patients without coronary artery disease [3]. Other studies have demonstrated that these patients have reduced coronary flow reserve and regional deficits in cardiac imaging [4]. Another possible mechanism for catecholamine-mediated myocardial stunning is direct muscle cell damage, as the density of adrenergic receptors in the apex is higher than in other areas of the myocardium [1]. Elevated levels of catecholamines lead to a concentration-dependent decrease in muscle cell viability, which can be explained

#### **Figure 1.**

*Schematic diagram of the pathological mechanism of stresses-induced cardiac dysfunction. β-AR, estrogen receptor beta; ROS/RNS, reactive oxygen/nitrogen species; MAPK, mitogen-activated protein kinase; Akt, protein kinase B; mTOR, mammalian target of rapamycin; SERCA2, sarcoplasmic reticulum calcium ATPase 2; RyR, ryanodine receptor; Nrf2, nuclear factor erythroid-derived 2-like 2; ATP, adenosine triphosphate; PDE5A, phosphodiesterase 5A; SIRT1, Sirtuin 1; PGC1-alpha, peroxisome proliferator-activated receptor gamma coactivator 1-alpha; OKG, cGMP-dependent protein kinase or protein kinase G.*

#### *Stress-Induced Cardiomyopathy DOI: http://dx.doi.org/10.5772/intechopen.105584*

by the marked release of creatine kinase in cells and the decreased viability due to calcium overload mediated by circulating AMPs [5]. Animal models suggest that catecholamines are a potential source of free radicals, which in turn may contribute to cardiomyopathy by promoting lipid peroxidation, increasing membrane permeability and muscle cell damage (**Figure 1**) [6]. Myocyte dysfunction may be caused by increased trans-sarcolemmal calcium influx and cellular calcium overload as free radicals interfere with the transport capacity of sodium and calcium transporters (**Figure 1**) [7]. Abnormal coronary blood flow has recently been reported in patients with stress-related myocardial dysfunction in the absence of obstructive disease [8]. Evidence that stress cardiomyopathy may be caused by neurogenic myocardial stunning also revealed a unique pattern of ventricular synergy with meta-iodobenzyl guanidine myocardial scintigraphy, suggesting the presence of cardiac sympathetic hyperactivity and maintaining coronary blood flow [9]. The distribution of primary cardiac injury did not correspond to the perfusion area of a single coronary artery. Plasma levels of catecholamines and stress-related neuropeptides are usually higher than the patient's physiological levels. Unlike polymorphonuclear inflammation in stress cardiomyopathy infarcts, contractile band necrosis is a distinct form of stress-induced cardiomyocyte injury characterized by hypercontraction of sarcomeres, eosinophilic transverse bands, and interstitial mononucleitis, and endomyocardial biopsy shows contractile band necrosis in patients with this syndrome [1]. Research shows that contractile band necrosis is a type of cell death detected as early as 2 min after cell injury, resulting in the release of cardiac enzymes [10]. Excessive circulating catecholamines and focal myocarditis contractile bands were found in the circulatory system of pheochromocytoma, suggesting a circulating catecholamine dependence of focal myocarditis [11], subarachnoid hemorrhage [12, 13], eclampsia [13], and in persons who died from fatal asthma necrosis [14]. All together, these suggest that catecholamines may be the link between emotional stress and heart damage (**Figure 1**).

A surge of stress hormones may temporarily damage the heart, many studies have found. Triggers of stress cardiomyopathy due to stress hormones include: (1) financial stress; (2) surgical stress; (3) bereavement stress; (4) asthma attack stress; (5) chronic disease or diagnostic stress; (6) other. Risk factors for stress cardiomyopathy are also quite different from any physical discomfort, mainly including: (1) age: most cases occur in people over 50; (2) intense physical or emotional events: such as a loved one accidental death, medical diagnosis, sudden economic decline or unemployment, divorce, physical abuse, car accident, major surgery, natural disaster, or intense fear; (3) side effects of certain medications: some are used to treat severe allergic reactions, diabetic neurological problems, depression symptoms or hypothyroidism drugs, etc. may cause a surge in stress hormones, leading to stress cardiomyopathy; (4) gender: this condition affects women much more than men; (5) neurological disorders; (6) previous or current mental illness.

Stress-induced cardiomyopathy is diagnosed by looking for certain markers to distinguish it from other heart conditions. Possible tests should include: (1) blood tests: to check the levels of certain fats, cholesterol, sugars, and proteins in the blood; (2) chest X-ray: common imaging tests of the lungs, heart, and aorta; (3) coronary angiography: this the procedure is usually done in conjunction with cardiac catheterization; (4) echocardiography: this test uses sound waves to take dynamic pictures of the heart's chambers and valves; (5) electrocardiogram (ECG): this test measures the electrical activity of the heart and can help determine whether a part of the heart

is enlarged, overworked, or damaged; (6) Magnetic Resonance Imaging (MRI): uses large magnets, radio waves, and a computer to produce images of the heart and blood vessels.


**Author details**

Marco Túllio Vilhena and Bardo Bodmann *Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil*

Umberto Rizza *Institute ISAC, National Research Council, Lecce, Italy*

Daniela Buske *Federal University of Pelotas, Pelotas, RS, Brazil*


**3.3 Collaborative and adaptive recommendations for personalized diet management**

The project CarpeDiem (Collaborative and Adaptive Recommender for PErsonalized DIEt Management) is aimed at providing intelligent and automatic support to people who want to follow a diet to stay fit, lose or gain weight. The concept of "diet" in CarpeDiem is considered in an integral way, taking into account nutrition, physical- and sleeping-activity. CarpeDiem users are elderly people who need to follow a strict diet, athletes who want to control their weight and stay healthy or simply, people who want to follow a healthy diet.

CarpeDiem is an IoT-based intelligent self-management system aimed at monitoring physical- and sleeping-activity, nutrition, as well as environmental data and lifestyle habits, with the final goal of providing personalized recommendations and nudges to foster behavior change towards healthier behaviors [14]. The selfmanagement system is bulit upon xCARE where intelligent techniques have been implemented for personalization and automatic monitoring, and a front-end is given in the form of an app to be installed in the citizen's smartphone.

As depicted in **Figure 8**, the IoT-based self-management system works with a set of data coming from different sources. CarpeDiem users wear an off-the-shelf activity tracker 24/7 to monitor physical- and sleep-activity as well as the energy expenditure in terms of calories. CarpeDiem users are also asked to monitor their weight once a week in order to take under control the Body Mass Index (BMI) and

15 Apple store: https://apps.apple.com/us/app/prehab/id1466618747 and Google Play: https://play. google.com/store/apps/details?id=org.eurecat.prehab hl = es*M*X

### *xCARE: A Development Platform for Supporting Smart and Pervasive Healthcare DOI: http://dx.doi.org/10.5772/intechopen.95951*

#### **Figure 7.**

*Sample screenshots of the PAPRIKA digital tools showing: (a) the list of prescriptions assigned to a patient, from the case management system, and (b) the home screen with the list of activities to be performed today, (c) the performed physical activity, and (d) the communications with the team of professionals, from the self-management system.*

to avoid reaching overweight and, thus, obesity. The CarpeDiem system integrates the LogMeal API [15], capable of recognizing meals through pictures taken from the smartphone camera. The pictures taken by using the CarpeDiem system are automatically sent to LogMeal that analyzes them and gives as output a list of meals. The citizen selects the right one and CarpeDiem automatically indicates the corresponding food group and calculates the number of calories and key nutrients of a dish portion, basing such calculation on the recipes also available through LogMeal. Moreover, questionnaires are used to directly ask the users regarding some lifestyle

**Figure 8.** *The CarpeDiem IoT system at a glance.*

habits. Finally, to be aware of the seasonality, the daylight hours, and further environmental data, we rely to the Dark Sky API16, whereas to monitor the air quality (currently, only in Catalonia) Dades Obertes by Generalitat de Catalunya is used17.

**Figure 9** shows how xCARE has been adapted to implement the CarpeDiem IoTbased self-management system; 10 microservices have been implemented:

	- Physical Activity, to monitor the walking activity by relying on an activity tracker.
	- Sleeping, through the activity tracker it automatically recognizes when the patient is sleeping or awake.
	- Nutrition, to monitor food intake by relying on the LogMeal app.
	- Weight, to monitor the increase/decrease of the weight by relying on a smart scale that automatically sends the data.
	- Questionnaires, to collect answers from the selected questionnaires: SATED [16], about the satisfaction of the citizen regarding her/his sleep; Smoke, on the number of cigarettes smoked on average during the week; Use of light-emitting screens, concerning the number of minutes spent on average using the smartphone or a tablet just before going to sleep; and Caffeine, to check the number of coffees, teas, and energy drinks the user drunk during the 7 hours before going to sleep, the day before.

16 https://darksky.net/dev

17 http://governobert.gencat.cat/en/dades\_obertes/

*xCARE: A Development Platform for Supporting Smart and Pervasive Healthcare DOI: http://dx.doi.org/10.5772/intechopen.95951*

**Figure 9.**

*xCARE adapted to CarpeDiem.*

	- PA\_RecSys, according to the goal in terms of number of steps, it calculates the adherence day by day considering also the day of the week and the weather.
	- S\_RecSys, analyzing the sleep habits gathering the information from the *Sleeping*, *Questionnaires*, and *Weight* microservices, it sends nudges and recommendations to follow better habits.
	- N\_RecSys, generating the profile of the user, this service sends suggestions to change habits, as well as general recommendations on healthy foods.
	- Third party, it implements the connections and calls the selected external APIs (i.e., activity trackers18, smart scales19, LogMeal, and open-data sources). This microservice works as an abstraction level. It only has to ask the third party connector for the information and wait for the data without worrying about the communication process and the different data model used.
	- Notifications, it sends to the front-end the notifications generated by any of the microservices.

18 In the current version, we use activity trackers from Fitbit (https://www.fitbit.com/) and Withings(https://www.withings.com/) for monitoring steps, sleeping habits, and energy expenditure;

19 In the current version, we use smart scales from Withings, for monitoring the weight and the BMI

**Figure 10.**

*The CarpeDiem app: (a) the main page with an overview of the activities; (b) a list of received notifications; (c) the setting page; (d) the physical activity details; (e) the sleeping activity details; (f) an example of food recognized from its picture.*

The CarpeDiem IoT-based self-management system is an app available in the Google Play (early access) for Android smartphones20. On July 2020, a pilot started with 14 healthy volunteers recruited in Eurecat ( 35.64 8.58 ± years old; 5 females; and 22.96 2.67 ± BMI). The pilot, which will end at the end of the year, has a threefold objective: (1) collecting feedback to improve the app and/or correct bugs; (2) testing the usability and evaluating the user experience; and (3) gathering new data to improve the 3 recommender systems and start implementing the holistic one. Results of the pilot will be calculated in terms of usability once the pilot ends.

**Figure 10** shows some screenshots of the Carpe Diem system: (a) the home page where the user has an overview of her/his status and may answer to the questionnaires; (b) a list of received notifications, each pillar represented by a different icon; (c) the setting page that shows, besides other information, that the app is linked to Fitbit; (d) the physical activity page with the summary of the steps per day and a green star indicating when the goal was achieved; (e) the sleeping page

20 https://play.google.com/store/apps/details?id=com.eurecat.carpediem

with the summary of the current week showing the sleeping hours and the efficiency as calculated by Fitbit; and (f) an example of recognized food (meatballs).


*3.6.2 Harvesting the vein graft*

This is an important step in the procedure and should not be taken lightly. Exact measurement and harvest of the vein graft is to be done by a competent surgeon very carefully. A slightly longer graft is taken in case damage is done to the ends. Too long a graft will cause tortuousness and kinking, while a shorter graft will tend to stretch and tear or leak.

A length of vein corresponding to the arterial defect is outlined (this is measured before the vein is cut) and using the same meticulous dissection techniques described in Section 3.5, the vein graft is extracted after applying clips (or ligating) both ends. Blood is removed from the vein manually and by irrigation. It is placed in the approximator (double) clamp on one side and the anastomosis is ready to begin.

This is started on the right side (for right-handed surgeons) because the artery gives a firm attachment point, and this is needed because the vein graft is freefloating making it difficult to put a suture through. A piece of coloured paper may be used to assist as background material adding oblique cuts to it, so it can help to hold sutures in place while repair is in progress [5].

The second anastomosis is started after the vein graft is checked to avoid any twisting (this will cause kinks and blockages) and that the double clamp is not straddling the repair site.

### **3.7 Pearls (positive practice)**

There are many pearls of wisdom and these are best summarised in tables according to the procedure that is being performed. **Table 1** describes general rules while **Tables 2** and **3** enumerate good practices for arterial and venous repair respectively.

#### **Table 1.**

*Pre-operative preparation. This table summarises the various measures the surgeon needs to take prior to starting the surgery to ensure its success.*

#### **Table 2.**

*Tips to achieve a good arterial repair. Points to remember when performing an arterial repair.*

#### **Positive practice points**

9. If arterial and venous anastomoses are done simultaneously, release the artery clamps just before the vein.

10. If there is a leak, the vein needs to be re-clamped and repaired after the blood is flushed out.

#### **Table 3.**

*Tips to achieve a good venous repair. Veins need more care in their handling and rest periods in between steps. A keen eye will prevent mishaps such as catching the back wall inadvertently.*

#### **3.8 Pitfalls (negative practice)**

While there are an enormous number of things that can go wrong with even the most experienced surgeon, I have tried to list the most common ones here in order as they appear in the text: Various arterial repair techniques of increasing difficulty (**Tables 4** and **5**), venous anastomosis (**Table 6**) and grafting (**Table 7**) and finally arteriotomy and end-to-side repair (**Table 8**).

#### **Table 4.**

*Arterial repair technique: Triangulation. The column on the left lists the positive actions to be practiced while the column on the right, the negative results thereof.*

**161**

**Table 8.**

*mentioned earlier.*

*Tips and Tricks in Microvascular Anastomoses DOI: http://dx.doi.org/10.5772/intechopen.92903*

1.Have the tips of the clamps facing you. 2.Make the first stitch furthest away from you

6.Divide the vessel ends into equal halves

7. Do not use too long a suture to prevent entanglement

3.Frequent picking up and letting go of the vessel wall.

5. Remember to reverse the vein graft for arterial flow to

*increases chances of success but also reduces time and effort taken.*

1. Perform the arteriotomy in the steps mentioned in the text. 2. Angle the adventitia scissors at 45° to make the cut.

8. Any technique may be used to perform the anastomosis.

10. If using continuous suturing, tighten as you move along.

5. Place a second stitch at 180° to the first.

9. Keep a short leash on the suture length

4. Start with the arterial wall from outside in and take the vein inside out.

6. Place the sutures radially spaced and not longitudinal to the arteriotomy 7. Put in a stay suture on the back wall mid-way between these first two stitches.

*needs to be taken in handling them because they tend to thrombose easily.*

**Pearls Pitfalls**

9.Make sure the knots are squarely tied and secure.

3.Start with the difficult side first and place sutures on either side of the first stitch 4.Avoid entangling your suture when placing the second half of the stitch

8.Keep the stitches evenly placed and pull the thread to evenly tighten it at the end

2.Incorrect handling of the vein with forceps, scissors or bipolar coagulator.

*Pointers in performing arterial repair. Tips to ensure good results in the two other (more challenging)*

*Pitfalls in venous anastomoses. These are the common mistakes made when anastomosing veins. Extra care*

*Pearls and pitfalls of vein graft harvest and anastomosis. Performing the right steps in the correct order not only*

3. Remember to reverse the vein graft and place it straightened out (while still in the clamps).

*Perfecting end-to-side repair. Pointers to bear in mind when performing this in addition to what has been*

1. Suturing two vessels of mismatched

2. The vein graft shortens after harvest! 3. A skeletonised graft is more susceptible to

4. Not checking for a twist before the second anastomosis may result in unnecessary

5. Using suction while graft is in the operative field is dangerous! Clamps also help avoid it

6. Getting the clamps in the way of the anastomoses may necessitate redoing it!

diameters

anguish!

being sucked in.

damage by the forceps.

**One-way-up technique**

5.Work your way up carefully **Continuous suture technique**

*techniques of arterial repair.*

1.Aggressive dissection and

4.Suturing inverted vessel edges. 5.Picking up the back wall.

1. Ensure right diameter of the vein graft 2. Measure the length of graft **before** harvesting. 3.  4. Lay the vein graft straightened out (untwisted) with both sides in clamps. This avoids twisting with no blood in

graft, while ensuring its visibility.

accommodate for the valves.

**Table 5.**

**Table 6.**

**Table 7.**

#### **One-way-up technique**

#### **Continuous suture technique**

#### **Table 5.**

*The Current Perspectives on Coronary Artery Bypass Grafting*

1. Meticulous handling of soft tissues

5. Rinse blood vessel and dilate it. 6. Approximate clamps

**Positive practice points**

see clearly

vessel

**Table 2.**

vein.

access

ends

**Table 3.**

2. Place (dark) background under vessel ends to

3. Gentle dissection to skeletonise and isolate

4. Methodical and careful removal of adventitia

1. Very gentle dissection and minimal handling of vein.

5. After dilation, bathe in lignocaine then apply the clamps. 6. Perform a meticulous anastomosis with evenly placed sutures. 7. Bathe in lignocaine (2–10%) before releasing the clamps. 8. After releasing clamps, allow the blood to flow for a few minutes.

2. Allow the vein to 'rest' after dissection then place it in the clamp. 3. Flush out all the blood, for any standing blood will cause thrombosis.

*A keen eye will prevent mishaps such as catching the back wall inadvertently.*

**Positive practice points Negative actions to avoid**

**Positive practice points Things to avoid**

*Tips to achieve a good arterial repair. Points to remember when performing an arterial repair.*

4. Dilate the vessel with a single prong, then both prongs of the dilator in different directions.

10. If there is a leak, the vein needs to be re-clamped and repaired after the blood is flushed out.

9. If arterial and venous anastomoses are done simultaneously, release the artery clamps just before the

*Tips to achieve a good venous repair. Veins need more care in their handling and rest periods in between steps.*

1. Tugging at unyielding tissues. 2. Grabbing the media (full thickness).

4. Using clamps larger than required. 5. Applying the diathermy to the main vessel.

of blood.

3. Performing an action without a clear view or in a pool

1. small and inadequate wound, poor retraction

2. Trying the anastomosis with short vessel ends 3. Persisting in the anastomosis when view is obstructed or when facing trouble.

4. Excessive traction (clamps too far apart) or obscured view of lumen (clamps too close). 5. Asymmetrical placement of sutures with bad

6. Struggling with needle then catching the back

leading to poor visualisation

coaptation of vessel ends

wall.

*Arterial repair technique: Triangulation. The column on the left lists the positive actions to be practiced while*

**3.8 Pitfalls (negative practice)**

arteriotomy and end-to-side repair (**Table 8**).

1. Have a clear operative field of vision and good

3. Properly trimmed adventitia and clean vessel

5. Divide the vessel into equal thirds and place sutures equidistant from both vessel ends. 6. Clear view and sure of needle placement.

*the column on the right, the negative results thereof.*

2. Mobilise a good length of vessel

4. Comfortable spacing of clamps

While there are an enormous number of things that can go wrong with even the most experienced surgeon, I have tried to list the most common ones here in order as they appear in the text: Various arterial repair techniques of increasing difficulty (**Tables 4** and **5**), venous anastomosis (**Table 6**) and grafting (**Table 7**) and finally

**160**

**Table 4.**

*Pointers in performing arterial repair. Tips to ensure good results in the two other (more challenging) techniques of arterial repair.*

#### **Table 6.**

*Pitfalls in venous anastomoses. These are the common mistakes made when anastomosing veins. Extra care needs to be taken in handling them because they tend to thrombose easily.*

#### **Table 7.**

*Pearls and pitfalls of vein graft harvest and anastomosis. Performing the right steps in the correct order not only increases chances of success but also reduces time and effort taken.*

#### **Table 8.**

*Perfecting end-to-side repair. Pointers to bear in mind when performing this in addition to what has been mentioned earlier.*