*2.1. Materials and Mix Proportions*

This study used cementless materials made from ultrafine fly ash from thermal power plants, ggbs from continuously operating steel plants, and co-fired fly ash from circulating fluidized bed boilers. The finenesses of ultrafine fly ash, ggbs and co-fired fly ash were 33,800, 5830 and 5130 cm2/g, respectively. The specific gravity and chemical composition of the three raw materials were analyzed as described in Table 1, where ultrafine fly ash and ggbs are the amorphous-oriented materials. The tests were conducted on paste specimens, and the proportions are shown in Table 2, which shows that there were 6 mixtures of various proportions for a fixed water-to-cementitious-material ratio (w/c) of 0.55. After casting, the molds were removed once the specimens had hardened at room temperature for 24 h. After demolding, each group of mixtures was kept in water and exposed to air, respectively. Relevant tests were conducted when the test age was reached.

**Table 1.** The specific gravity and chemical compositions of the three raw materials.

**Table 2.** Mix proportions (unit: g).


**4.4.4 Pulmonary interstitial emphysema**

Collection of gases outside of the normal air passages and inside the connective tissue of the peribronchovascular sheaths, interlobular septa, and visceral pleura may result from alveolar or bronchiolar rupture commonly in premature infants on mechanical ventilation. It is a radiographic and pathologic diagnosis frequently in conjunction with respiratory distress syndrome, meconium aspiration syndrome, amniotic fluid aspiration and infection.

#### **4.4.5 Acute generalized overinflation of the lung**

Usually reported in infants and children secondary to a number of clinical conditions affecting bronchioles, including asthma, cystic fibrosis, acute bronchiolitis, interstitial pneumonitis, atypical forms of acute laryngotracheobronchitis, aspiration of zinc stearate powder, chronic passive congestion secondary to a congenital cardiac lesion, and miliary tuberculosis.

Current Overview of COPD with Special Reference to Emphysema 127

particularly elastases such as MMP-9 and MMP-12, resulting in lung tissue injury. Degraded elastin fragments are chemotactic for macrophages, thus ensuing a self-propagating

T cells lympocytes, especially CD8+ cells are increased in airway walls and alveoli of patients with COPD(Saetta et al.,1998 as cited in Shapiro SD,2010). Airway epithelial cells in smokers with COPD have increased expression of CXCL10 (IP-10), the ligand for CXCR3 found on CD8+Tcells and thus may be the activation pathway for macrophages to produce MMP-12(Grumelli et al.,2004;Saetta et al.,2002 as cited in Shapiro SD,2010). Cytotoxic T cells may target epithelial cells and induce cell death, particularly those with (latent) viral

Elastin fragments can serve as autoantigens and immunoglobulin G (IgG) autoantibodies with avidity for pulmonary epithelium have been found in patients with COPD(Feghali-Bostwick et al.,2008;Lee et al.,2007 as cited in Shapiro SD,2010). Increased numbers of B cells and lymphoid follicles in the lung have raised interest in a possible autoimmune pathogenesis of COPD(Curtis et al.,2007;Taraseviciene-Stewart & Voelkel,2008 as cited in Shapiro SD,2010). Interplay of all these inflammatory pathways results in the tissue damage

Elastin and collagen is critical to the structural integrity of the lung. Experimental studies in animal lung models with instilled proteinases have replicated emphysematous changes(Gross et al.,1964 as cited in Shapiro SD,2010) resulting in an initial rapid increase in air space size due to direct elastolysis with diminution of lung elastin content at 24 hours followed by rapid restoration of total lung elastin to normal levels(Janoff et al.,1977;Snider et al.,1984 as cited in Shapiro SD,2010). The anatomic arrangement of the restored elastic fibers is grossly disordered (Kuhn & Senior,1978 as cited in Shapiro SD,2010). The tissue displays inflammation with neutrophils and macrophages with subsequent release of endogenous inflammatory mediators including IL-1β and TNF-α with endogenous proteolytic progression of the disease. Based on these studies and the association between A1PI deficiency with emphysema(Laurell & Eriksson,1963 as cited in Shapiro SD,2010), the proteinase-antiproteinase hypothesis proposed that the balance between matrix-degrading proteinases and their endogenous inhibitors determines whether the lung is protected or

Some proteinases such as NE and MMP-9 are bound to the surface of the neutrophil, they are resistant to complete inhibition by A1PI and tissue inhibitors of metalloproteinases (TIMPs). "Microenvironmental" concentration of proteinases and their proximity to the target site of matrix proteins when released from the neutrophil and macrophages, may explain how the balance tilts towards the proteinase function even in presence of adequate overall anti-proteinase in circulation(Owen & Campbell,1999 as cited in Shapiro SD,2010).

The serine proteinase Neutrophil elastase(NE) is suspected to be the major causative agent of tissue injury in COPD after the findings that patients deficient in its endogenous

There are four classes of proteinases, serine, cysteine, aspartic, and MMPs:

cycle(Houghton et al.,2006;Senior et al.,1980 as cited in Shapiro SD,2010).

infection.

that keeps adding up over the years.

susceptible to proteolytic injury.

**5.2.1 Serine proteinases**

**5.2 Proteinase-antiproteinase imbalance**

### **4.4.6 Bullous emphysematous blebs or cysts (pneumatoceles)**

They result from overdistention and rupture of alveoli during birth, or as sequelae of pneumonia and other infections. They have been observed in tuberculosis lesions during specific antibacterial therapy.


**Author details**

Ana Marta1,2\* and Bernardete Pessoa1,2

1 Centro Hospitalar Universitário do Porto (CHUP), Oporto, Portugal

2 Instituto Ciências Biomédicas Abel Salazar (ICBAS), Oporto, Portugal

\*Address all correspondence to<EMAIL_ADDRESS>
© 2021 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


*Perceptions of Digital Education to Accelerate the Flow of Knowledge DOI: http://dx.doi.org/10.5772/intechopen.111916*

#### **Figure 8.**

*Students' perception of the disadvantages of digital education.*

search for quantities that the respondent considers Mandatory, Attractive, and One-dimensional. **Table 2** presents the results based on the Kano model.

Based on the Kano model, we can see that most of the investigated parameters did not affect students in the process of digital education, they were Indifferent (I). Students perceive *Lower transportation costs* as an Attractive (A) parameter. However, they perceive *Internet connection* during digital education in contradictory ways (R).

Even though distance digital education did not significantly affect students' attitudes toward education, students perceive the *Interactivity* and *Efficiency* of this type of education as Mandatory requirements (M). The *Flexibility* of education is perceived as Attractive (A). The other parameters are presented by the opposite attitude – as Reverse (R). This means that students do not perceive digital education through parameters such as *Interesting*, *Fun*, *Communication*, and they also perceive the *Activity of teachers* and *students* in the same contradictory way. On the contrary, the Attractive (A) parameter is the improvement of their *skills* in the digital environment. Attractive attributes increase satisfaction exponentially and have the most significant impact.

Other advantages perceived as One-dimensional (O) are S*ufficient technical* and S*ufficient software equipment*. For students, these attributes represent a linear relationship between their expectations and satisfaction. Attractive parameters (A) were *Faster communication* and *Lower material costs*. On the other hand, they perceive *Social contact* in addition to *Internet connection* to be significantly contradictory – Reverse (R).

3D visualization (**Figure 9**) of the multivariate analysis of the Kano model results points to the differences in the influence of individual investigated parameters at individual grades of study (from the 1st year of bachelor's degree to the last year of the Master degree). 3D visualization presents the impact of the current year of study on the perception of education in the parameters: *Fun*, *Faster*, *Communication*, *Work with text*,*Time management,* and *Sufficient software equipment*. Other investigated parameters (**Figure 9**) have maintained the same perceptions within the grades of study. Both in the overall results and within individual grades of study, students perceive *Social communication* and *Internet connection* negatively – Reverse (R).

#### **Table 1.**

*Drivers and inhibitors of digital education in Slovakia.*

Interesting results can be observed, for example, with parameter *Active students*, where with a higher grade, student activity decreases from Attractive (A) to not having an impact - Indifferent (I). The opposite effect can be observed in the parameter *Search and convey information*, which changes from One-dimensional (O) to mustbe (M) as the grade increases. Equally significant changes can be observed in


**4. Conclusions**

The two crucial questions must be always addressed when considering RFA as a treatment option in a patient with primary or metastatic liver cancer: 1. Whether RFA is equal in curability to surgical resection for resectable malignant liver tumor, and 2. What additional survival benefit does RFA has over modern systemic therapies in the treatment of unresectable disease? The long-term results from clinical studies to date showed significantly better survival obtained from surgical resection for all types of resectable malignant liver tumors. Thus RFA cannot be regarded as an equally effective alternative of liver resection. On the other hand, if compared with systemic treatment alone there is enough clinical data to demonstrate that when local control is achieved by RFA it offers survival advantage (and even cure) for patients with unresectable disease. Unfortunately these facts are frequently misinterpreted and lead to misuse or abuse with RFA. In a survey from Germany 25.9% of patients undergoing RFA had a resectable tumor (Birth et al, 2004). This is partly because of the public pressure on physicians to refer their patients for minimally invasive treatment, rather than for major surgery, becomes heavier today. As a consequence many radiologists and gastroenterologists start to treat with percutaneous RFA patients with resectable tumors. On the other hand, surgeons that have no experience with hepatic surgery start to perform RFA as an alternative to resection in resectable cases, rather than referring these patients to the experienced liver surgeon. As the philosopher Abraham Maslow once said, "If the only tool you have is a hammer, then you tend to see every problem as a nail." However, when RFA is properly used in patients with primary and metastatic liver cancer its clinical benefits in terms of prolonged survival and even cure are indisputed. Today the RFA-device clearly is a necessary tool in the armamentarium of a liver surgeon.


**4.1 Institutional development for HCW management**

In designing a system for HCW management, it is important to consider three layers institutions levels; namely, global, national, and local levels. The institution at the global level is given by the internationally-accepted guidelines published by WHO [1] and other international organizations.

In any country, a national policy is the first step in creating a successful and sustainable HCW management system. The policy should be the blueprint to drive decision-making at a political level, for the allocation of resources, and mobilize government efforts to create the conditions to implement an HCW management system [28]. Based on the international guidelines, national-level legal systems and institutions for conducting proper HCW management will be formulated according to the given conditions of the country. Specific and comprehensive legislation and policy documents on HCW management with a clear designation of responsibilities to various stakeholders are required [18].

The following five basic principles are important in formulating an effective HCW management system, which was originally specified by the Global Healthcare Waste Project conducted by the United Nations Development Programme (UNDP) in cooperation with the Global Environment Facility (GEF) and WHO [29]:


*3.2. Ultimate Strength*

Figure 7 shows the load–displacement curves of the short-lapped-rebar splices under tensile loading. Clearly, Specimen L20-0.15 (Figure 7c) showed an obvious yielding stage and hardening stage and it had higher strength than Specimen L20-0.10 and L20-0.05. In contrast, the yielding stage was not exhibited for Specimen L20-0.05, and it fractured at an early stage due to the limited bond strength between grout and rebar. Table 4 lists the yield strength and the ultimate strength, including the ultimate bond strength of the short-lapped-rebar splices. Compared with the conventional splices without high strength grout [20] or transverse spiral hoops [21], the ultimate strength of the short-lapped-rebar splices was significantly improved.

**Figure 7.** *Cont*.

**Figure 7.** Load–displacement curves. (**a**) L12 (**b**) L16 (**c**) L20.

As listed in Table 4, the effect of the rebar diameter on the ultimate strength of the short-lapped-rebar splices is not significant. For example, the ultimate strength of Specimen L20-0.15-1 is 1.12 times of that of Specimen L12-0.15-1 when the rebar diameter increases from 12 mm to 20 mm.