**2.2.1 Glass substrate conditioning**

54 Advances in Unconventional Lithography

Polyethyleneimine (PEI), polyallylamine (PAH), poly-l-lysine (PLL) and polydiallyldimethylammonium chloride (PDDA) are common polycations used for multiple layer formation with polyanions such as polystyrene sulfonate (PSS) (Bertrand et al., 2000). Layer-by-layer assembly of polyelectrolytes has been combined with the use of colloidal particles. For instance, a film was made on silicon wafers precoated with thermally evaporated titanium, by adsorption of PDDA, followed by adsorption of PSS, followed by treatment with an aluminium chloride hydroxide solution (Hanarp et al., 2001, 2003). In another study, chemically patterned surfaces made by self-assembled monolayers (SAMs) were covered with a polyelectrolyte multilayer film, before adhesion of SiO2 silica particles or functionalized polystyrene latex particles (Chen et al., 2000). While a polyelectrolyte layer may provide a strong bond to colloidal particles, the drying process applied after particle adhesion may be crucial to obtain a regular and homogeneous monolayer (Hanarp et al.,

Structured hydrophobic surfaces have gained increasing interest because the roughness amplifies the hydrophobicity (Wenzel, 1936). This is exemplified by the Lotus effect, in which a dual size roughness seems to be important (Barthlott & Neinhuis, 1997; Patankar, 2004). Raspberry-like surface morphologies were created in different ways : styrene polymerization (Perro et al., 2006; Reculusa et al., 2002) or gold sputtering (Xiu et al., 2006) on silica particles , controlled aggregation of different surface-functionalized silica particles (Ming et al., 2005) or direct electrochemical synthesis of gold microaggregates (Li Z. et al.,

In this paper, we prepare surfaces covered with a homogeneous monolayer of colloidal particles, using adhesion of negatively charged polystyrene latex beads on a polycationprecoated glass substrate. The method is then extended to prepare surfaces presenting a bimodal roughness, by using latex particles of different sizes. The influence of substrate surface roughness on the behavior of mammalian cells has been of great concern in the last years (Nonckreman et al., 2010). Therefore, the stability of fabricated samples is tested in phosphate buffer saline (PBS), which simulates the pH and ionic strength of biological fluids. Note that here, the term "colloid" is used with the restrictive sense of lyophobic

Glass substrates were microscope coverslips (12 mm diameter, Menzel-Gläzer, Germany). Polyethyleneimine solution (PEI, Mw = 750 000), polyallylamine hydrochloride (PAH, Mw~70 000), poly-l-lysine hydrobromide (PLL, Mw = 70 000 to 150 000), poly(diallyldimethylammonium chloride) solution (lPDDA, Mw < 100 000; hPPDA, Mw = 400 000 to 500 000) were purchased from Sigma-Aldrich (St. Louis, MO, USA). Negatively charged polystyrene particles with two different sizes (sulfate latex, 65±6nm, 470±12nm) were purchased from Interfacial Dynamic Corporation (IDC, Tualatin, OR, USA). The composition of the phosphate buffer saline solution (PBS) was as follows: 137 mM NaCl, 6.4

Figure 1 presents the different steps of sample preparation, from the glass substrate to

mM KH2PO4, 2.68 mM KCl, 8 mM Na2HPO4; adjusted to pH 7.4 with 1M NaOH.

2003).

2007) and immobilization on a specific substrate.

**2. Materials and methods**

**2.2 Sample preparation**

surfaces with bimodal roughness.

**2.1 Materials**

colloidal particle, and thus distinguished from polyelectrolytes.

The glass coverslips were cleaned by overnight immersion in sulfochromic solution and rinsed with water, prior to polycation adsorption (Figure 1a). The pH and ionic strength (I) of the polycation solution were adjusted with NaOH and HCl, and NaCl, respectively. The polycation solution (1 ml) was poured into the wells of a tissue culture plate (Falcon, Becton Dickinson, Belgium, Ref. 353226), where the glass coverslips had been placed earlier, and was left in contact with the substrate for at least 2 h. Unless stated otherwise, the polycation solution was 10-5 M at pH 11 and I 10-2 M. The samples were rinsed by 6 successive dilutions to avoid exposure to air. Each rinsing step was performed by adding 2 ml of deionized water (produced by a Milli-Q plus system from Millipore, Molsheim, France), stirring gently, and removing 2 ml of liquid. They were then dried under a gentle nitrogen flow (Figure 1b).

Fig. 1. Schematic representation of the steps used for sample fabrication. Glass substrate (a), polycation-conditioned glass substrate (b), substrate with a layer of adhering particles (c), surface with bimodal I roughness (d), substrate with a layer of adhering particles conditioned with the polycation (e), surface with bimodal II roughness (f).


**6. Conclusion**

In last couple of decades, the application of Microwave enegy has emerged a promising tool for synthesis of novel molecule in the area of drug research, in synthesis of nano material, in catalyst field, in inorganic synthesis, in CO and CO2 capture reactions, paint industry, in extraction of products from natural sources etc. It blossemed as a reliable alternavite of conventional heating due to high speed or shortening of reaction time; simplicity i.e.reaction can be performed in sealed and open glass vials with wide range of options; with high productivity i.e. almost 200–400% more than conventional means. The MW assisted reactions will be a one of the best method to synthesise diverse type of molecules of interest.


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**6**

*Spain*

**Using SVD Analysis of Combined Altimetry and**

**Ocean Color Satellite Data for Assessing Basin**

The ocean is a highly variable system affected by a large range of processes that spans the continuous spectra of spatial and temporal scales (Wunsch, 1996). The spatial scales of variation range from basin-wide gyres (thousands of kilometers) to turbulence (less than a meter), and the time scales from those that are climate related (decades) to short-term processes (seconds). Information on this whole range of processes is required for the comprehension of the marine system dynamics. Despite the continuous advances in technology, remote sensing is the only observing platform capable of providing continuous information on biological and physical properties over vast areas of the ocean. With some limitations, the regular and repeated coverage offered by satellites is still unachievable

Because the ocean is largely opaque over much of the usable electromagnetic spectrum, the ability of satellites to capture ocean properties is generally confined to the surface. Nevertheless, satellite-borne sensors provide us with a relatively large range of measurements such as sea surface color, sea surface height, sea surface temperature, sea surface winds, sea surface salinity, waves, and to a lesser extent, current fields. The availability, for the first time, of time series expanding for several years or decades at regional and global ocean scales has changed our perception of the ocean (Barber & Hilting, 2000). A majority of these measurements is restricted to physical properties such as temperature, sea level or sea surface roughness and inferred variables (currents, winds, etc.). The only routinely acquired satellite measurement providing information on ocean biological processes is sea surface color. Since early measurements obtained by the Coastal Zone Color Scanner (CZCS), sea color sensors have provided quantitative information on the distribution of surface chlorophyll (CHL) concentration (an index of phytoplankton biomass) at regional to global scales and its variability in space and time (e.g., Abbott & Zion, 1987; Antoine et al., 2005; Behrenfeld et al., 2001). This information is relevant to estimate the ocean productivity, a key factor for understanding the dynamics of pelagic

**1. Introduction**

through in situ measurements.

foodwebs and some aspects of climate change.

**Scale Physical-Biological Coupling in**

*Institut Mediterrani d'Estudis Avançats, IMEDEA (UIB-CSIC)*

**the Mediterranean Sea**

Antoni Jordi and Gotzon Basterretxea


# **Sustainable Agricultural, Biological, and Environmental Engineering Applications**

Edited by Muhammad Sultan, Yuguang Zhou, Redmond R. Shamshiri and Aitazaz A. Farooque Printed Edition of the Special Issue Published in *Sustainability*

www.mdpi.com/journal/sustainability


**7. Conclusions**

*H. pylori* infection is detected significantly more often among patients with chronic liver injury. This is especially dangerous in patients with liver cirrhosis. In this group of patients, *H. pylori* infection may significantly worsen liver function, affecting hyperammonemia, increase in portal pressure, and development of esophageal varices. Testing for and treating this infection is of paramount importance for these patients.

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2011.00883.x

Current research on the impact of *H. pylori* infection in patients with chronic liver damage is inadequate. This points to the desirability of further research, particularly among patients with severe liver damage.


**7. Conclusions**

Several studies have found evidence that children with sensory processing disorder can gain more insight into their development by assessing and providing an exact intervention at their right age and time. I hope this chapter would help out the parents to analyze the difficulties the children go through and guide them in the right path.


Deposition of Silver Nanoparticles on Indium Tin Oxide Substrates by Plasma-Assisted Hot-Filament Evaporation

*Abtisam Hasan Hamood Al-Masoodi, Boon Tong Goh, Ahmed H.H. Al-Masoodi and Wan Haliza Binti Abd Majid*


*Article* **Nonlinear Dynamics of Exclusive Excited-State Emission Quantum Dot Lasers Under Optical Injection**

**Zai-Fu Jiang 1,2, Zheng-Mao Wu 1,\*, Elumalai Jayaprasath 1, Wen-Yan Yang 1,3, Chun-Xia Hu 1,4 and Guang-Qiong Xia 1,\***

Received: 28 April 2019; Accepted: 23 May 2019; Published: 27 May 2019

**Abstract:** We numerically investigate the nonlinear dynamic properties of an exclusive excited-state (ES) emission quantum dot (QD) laser under optical injection. The results show that, under suitable injection parameters, the ES-QD laser can exhibit rich nonlinear dynamical behaviors, such as injection locking (IL), period one (P1), period two (P2), multi-period (MP), and chaotic pulsation (CP). Through mapping these dynamic states in the parameter space of the frequency detuning and the injection coefficient, it can be found that the IL occupies a wide region and the dynamic evolution routes appear in multiple forms. Via permutation entropy (PE) calculation to quantify the complexity of the CP state, the parameter range for acquiring the chaos with high complexity can be determined. Moreover, the influence of the linewidth enhancement factor (LEF) on the dynamical state of the ES-QD laser is analyzed. With the increase of the LEF value, the chaotic area shrinks (expands) in the negative (positive) frequency detuning region, and the IL region gradually shifts towards the negative frequency detuning.

**Keywords:** quantum dot lasers; excited-state; nonlinear dynamics; optical injection

#### **1. Introduction**

Under external perturbations, semiconductor lasers (SLs) can exhibit various nonlinear dynamical behaviors, such as the period one (P1), period two (P2), multi-period (MP), and chaos (CO) etc. [1–5], which has attracted much attention due to their potential applications in photonic microwave amplifiers [6], optical frequency converters [7], wireless optical fiber communication [8], all-optical logic gates [9], laser Doppler velocimeters [10], secure optical communication, and random bit generation [11–13].

Among different types of SLs, a self-organized SL with quantum dot (QD) structure has turned out to be very promising [14–17] due to such unique properties as low relative intensity noise [18], a small linewidth enhancement factor (LEF) [19,20], and high temperature stability [21]. For the QD lasers, three-dimensional quantum confinement gives rise to discrete energy levels for electrons and holes. Under a relatively low bias current, the recombination of electrons and holes in the ground-state (GS) results in sole GS emission. As the bias current is increased, the population of the excited-state (ES) increases. When the current exceeds the secondary threshold, the QD lasers simultaneously emit

in both the GS and the ES. Moreover, when the bias current is high enough, the QD lasers may emit solely in the ES [22]. In recent years, the nonlinear dynamics of the QD lasers subject to external perturbations have received considerable attention [23–29]. For a QD laser emitting solely in the GS, Erneux et al. have theoretically and experimentally investigated its dynamic response under optical injection, and the results show that the laser has similar dynamic features to the Class A laser [23]. Goulding et al. have reported the excitability after introducing optical injection, and the excitable pulses and the random conversion between the stable and unstable states were observed [24]. Carroll et al. have experimentally studied the instabilities resulted by optical feedback and the irregular power drop-outs and the periodic pulsations are presented [25]. For the case of a QD laser simultaneously emitting in the GS and the ES, Viktorov et al. have reported the low-frequency inverse phase fluctuation phenomenon of the ES and GS lasing intensities caused by optical feedback [26]. Olejniczak et al. have theoretically demonstrated that the ES lasing intensity shows regular picosecond pulses and pulse packages when the wavelength of injection light is close to the lasing wavelength of the GS mode [27]. For a QD laser emitting solely in the ES under high bias currents, a tunable all-optical gating has been implemented after introducing optical injection [28], and the hysteresis phenomenon has also been observed by scanning the injection power along different variation routes [29].

Recently, relevant investigations demonstrated that, through adopting some special techniques during the manufacture, QD lasers can emit exclusively in the ES [30–32], named as ES-QD lasers in this work. Different from ordinary QD lasers, such ES-QD lasers always emit in the ES while the GS is suppressed totally [30]. Compared with ordinary QD lasers, ES-QD lasers possess higher differential gain, a smaller relaxation oscillation (RO) damping rate, a and smaller K-factor [30,31], which are helpful for enhancing the modulation response and the nonlinear dynamical properties [30–35]. The modulation speeds of ES-QD lasers can reach 25 Gbps (on-off keying (OOK)) and 35 Gbps (pulse-amplitude modulation (PAM)) [30,32]. Meanwhile, ES-QD lasers possess broad modulation bandwidths and low chirp-to-power ratios [33]. In addition, through introducing optical feedback, diverse nonlinear dynamic states, such as the periodic and chaotic states, have been observed in the ES-QD lasers [34,35]. Besides the modulation and optical feedback, optical injection is another frequently used external perturbation technique. We have noted that related research on the nonlinear dynamics of ES-QD lasers under optical injection is rarely reported. In this work, based on a theoretical model of ES-QD lasers [33,36–38], after taking into account optical injection, the nonlinear dynamics of ES-QD lasers under optical injection are investigated. The mapping of the dynamical states in the parameter space of frequency detuning and the injection coefficient is presented, and the effect of the linewidth enhancement factor (LEF) on the nonlinear dynamics of ES-QD lasers is also discussed.

#### **2. Theoretical Model**

A schematic diagram of the carrier dynamics for ES-QD lasers is shown in Figure 1. Here, charged electrons and holes are regarded as the neutral excitons (electron-hole pairs), and the differences among QDs are neglected, i.e., there is only one QD ensemble in the active region [38]. By electric pumping, the carriers are directly pumped into the reservoir (RS) plane. Through Auger processes, some carriers are captured from RS to ES during the time of τ*RS ES*, and then some carriers relax from ES to GS during the time of τ*ES GS* [37]. Additionally, due to the thermal excitations, some carriers in GS (ES) escape to ES (RS) during the time of τ*GS ES* (τ*ES RS*) [37]. It is assumed that the system is in quasi-equilibrium and the carrier number in each energy level satisfies the Fermi–Dirac distribution. It is worth noting that this model ignores the direct carrier capture path from RS to GS. The stimulated radiation can occur in ES or GS for ordinary QD lasers, but only the ES lases in the ES-QD lasers [33]. After referring to References [33,36–38] and taking optical injection into account, the rate equations for optical injection ES-QD lasers can be described by the following:

$$\frac{d\eta\_{RS}}{dt} = \frac{\eta I}{\varepsilon} + \frac{N\_{ES}}{\tau\_{RS}^{ES}} - \frac{N\_{RS}}{\tau\_{ES}^{RS}}(1 - \rho\_{ES}) - \frac{N\_{RS}}{\tau\_{RS}^{spon}} \tag{1}$$

$$\frac{dN\_{ES}}{dt} = \left(\frac{N\_{RS}}{\tau\_{ES}^{RS}} + \frac{N\_{GS}}{\tau\_{ES}^{GS}}\right) (1 - \rho\_{ES}) - \frac{N\_{ES}}{\tau\_{RS}^{ES}} - \frac{N\_{ES}}{\tau\_{GS}^{ES}} (1 - \rho\_{GS}) - \frac{N\_{ES}}{\tau\_{ES}^{span}} - \Gamma\_p \upsilon\_{\mathcal{S}} \varrho\_{ES} \mathbf{S}\_{\mathbf{v}} \tag{2}$$

$$\frac{dN\_{GS}}{dt} = \frac{N\_{ES}}{\tau\_{GS}^{ES}} (1 - \rho\_{GS}) - \frac{N\_{GS}}{\tau\_{ES}^{GS}} (1 - \rho\_{ES}) - \frac{N\_{GS}}{\tau\_{GS}^{\text{spou}}} \tag{3}$$

$$\frac{dS}{dt} = \left(\Gamma\_p \upsilon\_{\mathcal{S}} \underline{g}\_{ES} - \frac{1}{\tau\_p}\right) \mathcal{S} + \beta\_{\mathcal{sp}} \frac{N\_{ES}}{\tau\_{ES}^{\rm{spom}}} + \frac{2K}{\tau\_{\rm int}} \sqrt{S\_0 S} \cos\left(2\pi \Delta vt - \phi\right),\tag{4}$$

$$\frac{d\phi}{dt} = \frac{1}{2}a\Big(\Gamma\_p \upsilon\_g g\_{ES} - \frac{1}{\tau\_p}\Big) + \frac{K}{\tau\_{\rm in}} \sqrt{\frac{S\_0}{S}} \sin(2\pi\Delta\nu t - \phi)\Big),\tag{5}$$

where abbreviations *RS*, *ES*, and *GS* stand for the reservoir, the excited-state, and the ground-state, respectively, and superscript *spon* represents the spontaneous emission. The value *N* denotes the carrier number, *S* is the photon number, and φ is the electric field phase. The value *I* denotes the bias current, η represents the current pumping efficiency, and *e* represents the elementary charge of an electron. The value Γ*p* denotes the optical confinement factor. The values τ*p* and τ*spon* represent the photon lifetime and the spontaneous decay time, respectively. The value *vg* is the group velocity of light, and τ*in* is the round-trip time of light in a cavity of length *L*. The terms ρ*GS* (=*NGS*/2*NB*) and ρ*ES* (=*NES*/4*NB*) represent the occupancy probabilities of carriers in GS and ES, where *NB* denotes the total QD number. The terms 1 − ρ*GS* and 1 − ρ*ES* are the Pauli-blocking factors [38,39], which correspond to the probabilities of empty QD state in GS and ES. The value *S*0 is the photon number of the free-running ES-QD laser. The value *K* is the injection coefficient and Δν represents the frequency detuning between the injection light and the free-running ES-QD laser. The gain coefficient, *gES*, of ES is expressed as follows:

$$\text{g\_{ES}} = \frac{a\_{ES}}{1 + \xi \frac{S}{V\_S}} \frac{N\_B}{V\_B} (2\rho\_{ES} - 1)\_\prime \tag{6}$$

where *aES* denotes the differential gain of ES, ξ represents the gain limiting factor, *VB* is the total volume of QDs, and *VS* denotes the intra-cavity laser field volume.

**Figure 1.** Schematic diagram of the carrier dynamics for the ES-QD lasers. GS: ground-state; ES: excited-state; RS: reservoir.

Numerical methods for the solution of ordinary differential equations are the main tools to investigate the nonlinear dynamical systems [40,41]. In this work, a desktop PC with a six-core processor (AMD Ryzen 5 1600X, Advanced Micro Devices Inc., Santa Clara, CA, USA) and 16GB installed memory is used to perform the simulation, and we adopt the ode45 solver (Fourth-Fifth order Runge–Kutta algorithm, where the fourth-order provides the candidate solutions and the fifth-order controls the errors) in MATLAB software to solve the above differential equations, after taking into account the accuracy and speed of the calculations. Since the step size will affect the simulation results [40], we use the adaptive step size in numerical simulations. The used parameters for the ES-QD laser during the simulations are given in Table 1 [33,38].

**Table 1.** Simulation parameters of the QD laser.

#### **3. Results and Discussion**

Figure 2a shows the power-current (*P*-*I*) curve of the free-running ES-QD laser. Obviously, the threshold current (*Ith*) of the laser is about 92.0 mA. As the current increased from 92.0 mA to 250.0 mA, the output power increased linearly. Figure 2b displays the variations of the carrier number in ES and GS with the current. From this diagram, it can be seen that the carrier numbers in ES and GS are almost constant for the laser biased above the threshold, and the former is larger since the degeneracy of ES is twice that of GS [33]. Furthermore, by using small signal analysis, the relaxation oscillation (RO) frequencies of the ES-QD laser at different bias currents can be obtained, as shown in Figure 2c. With the increase of the current, the RO frequency increases nonlinearly. In the following discussion, the current of the laser is fixed at *I* = 184.0 mA (= 2*Ith*) and the corresponding RO frequency is about 7.60 GHz.

**Figure 2.** Output power (**a**), carrier number (**b**), and relaxation oscillation (RO) frequency (**c**) of the ES-QD laser as a function of the bias current.

Our simulations demonstrate that after introducing an optical injection, the ES-QD laser can exhibit different dynamical states. Figure 3 shows the time series, power spectra, and phase portraits of the ES-QD laser, under optical injection with frequency detuning Δν = −14.00 GHz and different injection coefficient *K*. For *K* = 0.30 (Figure 3a1–a3), the time series behaves as a periodic oscillation whose fundamental frequency is about 14.26 GHz, which can be captured from the power spectrum, and the trajectories of phase portrait show a clear limit cycle feature. As a result, it can be determined that the ES-QD laser operates at the period one (P1) oscillation. For *K* = 0.33 (Figure 3b1–b3), the periodic waveform with two peak intensities can be clearly observed in the time series, the sub-harmonic frequency (about 7.13 GHz) appears in the power spectrum, and the corresponding phase portrait possesses two loops that are intertwined together. Under this case, the ES-QD laser exhibits the period two (P2) oscillation. For *K* = 0.49 (Figure 3c1–c3), multiple peaks with different intensities emerge in the time series, multiple new frequency components appear upon the power spectrum, and the phase portrait shows the overlap alternation of multiple loops. Therefore, the dynamics of the ES-QD laser can be judged as the multi-period (MP) state. For *K* = 0.64 (Figure 3d1–d3), the peak intensity of the time series behaves as an irregular fluctuation, the associated power spectrum broadens, and the phase portrait exhibits a strange attractor. Based on these features, the dynamic state of the ES-QD laser can be determined to be the chaotic pulsation (CP) state. When *K* is increased to 0.90 (Figure 3e1–e3), the time series shows a stable output, no obvious peak can be observed in the power spectrum, and the corresponding phase portrait shows a stable point. Further calculation shows that, under this condition, the lasing frequency of the ES-QD laser is just the frequency of the injection light. As a result, it can be judged that the ES-QD laser operates at the injection locking (IL) state. ×

**Figure 3.** Time series (first column), power spectra (second column), and phase portraits (third column) of the ES-QD laser for Δν = −14.00 GHz and different *K*, where *K* = 0.30 (a1–a3), *K* = 0.33 (b1–b3), *K* = 0.49 (c1–c3), *K* = 0.64 (d1–d3), and *K* = 0.90 (e1–e3).

Figure 4 shows a bifurcation diagram for observing the dynamical evolution of the ES-QD laser with the injection coefficient *K* at Δν = −14.00 GHz. As shown in this diagram, when the injection coefficient *K* increases from 0 to 0.32, the output waveform has two extreme values and the ES-QD laser can be judged to operate at the period one (P1) oscillation. When the injection coefficient *K* increases from 0.32 to 0.47, the output waveform has four extreme values and the laser can be determined to be the period two (P2) oscillation. Further increasing the injection coefficient *K* from 0.47 to 1, the ES-QD laser presents the multi-period (MP), the chaotic pulsation (CP), and the injection locking (IL).

**Figure 4.** Bifurcation diagrams of the ES-QD laser for Δν = −14.00 GHz.

The above results are obtained under different *K* for a fixed Δν = −14.00 GHz. Next, in order to understand the nonlinear dynamical evolution of the ES-QD laser more comprehensively, a mapping of the dynamic states in the parameter space of *K* and Δν is presented in Figure 5a, where different colors represent different dynamical states. As shown in this diagram, some dynamic states including injection locking (IL), period one (P1), period two (P2), multi-period (MP), and chaotic pulsation (CP) can be observed for the ES-QD laser, under different injection parameters. It is worth noting that a large area of IL appears in the map due to optical injection. In the positive frequency detuning region, around Δν = 4.00 GHz, the P1-P2-MP-IL dynamic evolution is exhibited with the increase of the injection coefficient, but the CP does not emerge. In the negative detuning region, around Δν = −4.00 GHz and Δν = −14.00 GHz, the typical dynamic evolutions of P1-P2-IL and P1-P2-MP-CP-MP-IL are presented with the increase of the injection coefficient, respectively. It can be seen that the ES-QD laser, under optical injection, can output abundantly dynamical states and exhibit multiple forms of dynamic evolution routes. In addition, we have noticed that the CP state mainly exists in the regions of 0.48 < *K* < 0.68 and −15.00 GHz < Δν < −13.00 GHz. In order to further explore the characteristics of the CP state, we have calculated the normalized permutation entropy (PE), *hs*, to quantify the complexity of the CP signal, and the PE is defined as follows [42,43]. The time series {*S*(*m*), *m* = 1, 2, ... , *N*} are firstly reconstructed into a set of D-dimensional vectors after choosing an appropriate embedding dimension *D*, and then we study all *D*! permutation π of order *D*. For each π, the relative frequency (*#* means number) is determined as follows:

$$p(\pi) = \frac{\#\{m | m \le N - D, \ (S\_{m+1}, \dots, S\_{m+D}) \text{ has type } \pi\}}{N - D + 1}. \tag{7}$$

The PE is given by

$$h[p] = -\sum p(\pi) \log(p(\pi)).\tag{8}$$

Then, the normalized PE is further defined as follows:

$$h\_s = \frac{h[p]}{h\_{\text{max}}} = \frac{-\sum p(\pi)\log(p(\pi))}{\log(D!)},\tag{9}$$

where *hs* = 0 and *hs* = 1 represent a completely predictable process and a completely stochastic process with uniform probability distribution, respectively. We use a 670 ns length of the time series and the embedding dimension *D* = 6 to calculate the PE. Figure 5b displays the complexity of the CP in the parameter space of *K* and Δν, where different colors represent different complexity values. From this diagram, it can be observed that the CP state with a high complexity of 0.95 < *hs* < 0.98 is mainly located at the regions of 0.55< *K* < 0.67 and −14.50 GHz < Δν < −13.30 GHz.

**Figure 5.** (**a**) Nonlinear dynamics distribution and (**b**) corresponding chaotic region complexity distribution of the ES-QD laser in the parameter space of injection coefficient and frequency detuning. IL: injection locking, P1: period one, P2: period two, MP: multi-period, CP: chaotic pulsation.

It is well known that the linewidth enhancement factor (LEF) is one of key parameters that affects the spectral linewidth, the mode stability, as well as the nonlinear dynamics of SLs under external perturbations [44–46]. The above results were obtained under a fixed LEF value of 1.3. In Reference [33], it is pointed out that the differential gain of each energy level and the energy separation between resonant and non-resonant states will have a profound impact on the LEF value. As a result, it is necessary to investigate the effect of the LEF on the nonlinear dynamics of ES-QD lasers. Figure 6 shows the mappings of the nonlinear dynamic behaviors in the parameter space of Δν and K under different α. For α = 0.5 (Figure 6a), in the region of Δν > 0, the injection locking (IL), period one (P1), period two (P2), and multi-period (MP) can be observed, while in the region of Δν < 0, besides IL, P1, P2, and MP, a chaotic pulsation (CP) region (brown) can be found nearby (Δν = −10.00 GHz, *K* = 0.45), and is surrounded by the MP state. Additionally, as shown in this diagram, the stable IL region (dark blue) almost symmetrically distributes in both sides of Δν = 0. For α = 1.0, 1.5 (Figure 6b,c), with the increase of the LEF value, the area of the P2 region (light green) increases significantly, the IL region slowly moves towards the range of Δν < 0, and the CP region shifts to nearby (Δν = −15.00 GHz, *K* = 0.6). For α = 2.0, 2.5, and 3.0 (Figure 6d–f), as the LEF value increases, the IL region gradually shifts to the negative detuning side and asymmetrically distributes in both sides of Δν = 0, but its area is approximately unchanged. In addition, the area of the CP region gradually expands (shrinks) in the range of Δν > 0 (Δν < 0), and finally predominantly distributes nearby (Δν = 6.00 GHz, *K* = 0.25). Moreover, the area of the P2 region is approximately unchanged and the area of the MP region (orange) gradually shrinks. It can be seen that the change of LEF value profoundly affects the dynamic distribution of the ES-QD laser under optical injection.

In addition, it should be pointed out that the classical Fourth-Fifth order Runge–Kutta method is used for numerical simulation in this work. Relevant research shows that different numerical simulation methods will affect the discrete behavior of nonlinear systems and may obtain different results [41]. As a result, we will concern and verify the validity of different numerical simulation methods by combining experimental observations in our next research.

**Figure 6.** Mappings of the nonlinear dynamics distribution of the ES-QD Laser in the parameter space of injection strength and frequency detuning for different LEF, where (**a**) α = 0.5, (**b**) α = 1.0, (**c**) α = 1.5, (**d**) α = 2.0, (**e**) α = 2.5, and (**f**) α = 3.0. IL: injection locking, P1: period one, P2: period two, MP: multi-period, CP: chaotic pulsation.

#### **4. Conclusions**

In summary, the nonlinear dynamics of an exclusive ES emission QD laser under optical injection have been investigated numerically. The results show that, under suitable optical injection parameters, the ES-QD laser can exhibit a series of nonlinear dynamical behaviors such as injection locking (IL), period one (P1), period two (P2), multi-period (MP) and chaotic pulsation (CP). Through mapping these dynamic states in the parameter space of Δν and *K*, the typical dynamic evolution routes of P1-P2-IL, P1-P2-MP-IL, and P1-P2-MP-CP-MP-IL are observed. The IL region has a large area and the CP is mainly distributed in the regions of 0.48 < *K* < 0.68 and −15.00 GHz < Δν < −13.00 GHz. Through the PE calculation to quantify the complexity of CP state, the CP with a high complexity 0.95 < *hs* < 0.98 is located at the regions of 0.55 < *K* < 0.67 and −14.50 GHz < Δν < −13.30 GHz. In addition, the influence of the linewidth enhancement factor (LEF) on the dynamic behavior distributions of the ES-QD laser is also discussed. With the increase of the LEF value, the CP region moves to the positive frequency detuning range and distributes nearby (Δν = 6.00 GHz, *K* = 0.25), the area of the MP gradually shrinks, and the IL region gradually shifts to the negative frequency detuning range and its area is approximately unchanged. Compared with the dynamical characteristics of distributed feedback (DFB) lasers under optical injection, the dynamical evolutionary trends are similar, but the chaotic region of DFB lasers is larger and the IL region for DFB lasers will gradually disappear with the increase of LEF [45]. These differences may be due to the three-dimensional restriction of carriers in QD lasers. We believe that this work would be helpful for understanding the nonlinear dynamics of ES-QD lasers under optical injection and then exploiting related applications.

**Author Contributions:** Z.-F.J. was responsible for the numerical simulation, analyzing the results, and the writing of the paper. E.J., W.-Y.Y. and C.-X.H. were responsible for writing and revising the manuscript. Z.-M.W. and G.-Q.X. were responsible for the discussion of the results and reviewing/editing/proof-reading of the manuscript.

**Funding:** This research was funded by the National Natural Science Foundation of China (Grant Nos. 61475127, 61575163, 61775184, and 61875167).

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

#### **References**

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).


*Article* **New Insights on NETosis Induced by** *Entamoeba histolytica***: Dependence on ROS from Amoebas and Extracellular MPO Activity**

**César Díaz-Godínez 1, Joshue Fabián Jorge-Rosas 1, Mario Néquiz 2, Santiago Martínez-Calvillo 3 , Juan P. Laclette 1, Carlos Rosales 1,\* and Julio C. Carrero 1,\***

**Abstract:** NETosis is a neutrophil process involving sequential steps from pathogen detection to the release of DNA harboring antimicrobial proteins, including the central generation of NADPH oxidase dependent or independent ROS. Previously, we reported that NETosis triggered by *Entamoeba histolytica* trophozoites is independent of NADPH oxidase activity in neutrophils, but dependent on the viability of the parasites and no ROS source was identified. Here, we explored the possibility that *E. histolytica* trophozoites serve as the ROS source for NETosis. NET quantitation was performed using SYTOX® Green assay in the presence of selective inhibitors and scavengers. We observed that respiratory burst in neutrophils was inhibited by trophozoites in a dose dependent manner. Mitochondrial ROS was not also necessary, as the mitochondrial scavenger mitoTEMPO did not affect the process. Surprisingly, ROS-deficient amoebas obtained by pre-treatment with pyrocatechol were less likely to induce NETs. Additionally, we detected the presence of MPO on the cell surface of trophozoites after the interaction with neutrophils and found that luminol and isoluminol, intracellular and extracellular scavengers for MPO derived ROS reduced the amount of NET triggered by amoebas. These data suggest that ROS generated by trophozoites and processed by the extracellular MPO during the contact with neutrophils are required for *E. histolytica* induced NETosis.

**Keywords:** *Entamoeba histolytica*; neutrophil extracellular traps (NETs); neutrophils; reactive oxygen species (ROS); myeloperoxidase


**8. Conclusion**

*Cystic Fibrosis - Heterogeneity and Personalized Treatment*

typically have more severe disease phenotypes.

**6. Implications of modulator therapy**

access to these agents.

through a public system.

**7. Future directions**

Phe508del-MF mutations.

Phe508del mutation, if small molecule therapy could significantly increase the amount of functional protein for this mutation, a greater range of CF individuals could be treated as then the therapy would be suitable for those individuals with the

Next generation CFTR correctors are under evaluation in combination with tezacaftor/ivacaftor. Phase 2 and 3 trials of these triple therapy agents; VX-659 and VX-445 have provided further exciting results. These corrector agents have a different structure and mechanism of action and provide additive function to the other two agents. For individuals homozygous for Phe508del an increase in absolute ppFEV1 was 9.7% for VX-659 treatment and 11% for VX-445 therapy. Greater increases in lung function were seen for patients with Phe508del-MF mutations; the absolute change in ppFEV1 was 13.3 and 13.8% for VX-659 and VX-445 respectively. These increases were also alongside significant improvements in quality of life and have been maintained in subsequent phase 3 interim report analyses [59–62]. These are incredible outcomes for individuals with more severe mutations and thus who

Important advances in the clinical outcomes for individuals with CF have been possible since the introduction of modulator therapy. Unfortunately these treatments are currently associated with a substantial cost and as a result are not available for all eligible patients. In the United States the Food and Drug Administration (FDA) has approved all four of the currently available modulator therapies. Some European countries and Australia, have access to ivacaftor, lumacaftor/ivacaftor and tezacaftor/ivacaftor [63]. However, worldwide there is significant inequality of

As an increasing number of modulator agents become available, the CF community will need to determine how they can enable patients to receive these expensive therapies. If funding bodies are going to approve them, it is likely that they will require significant clinical outcomes from their use, especially when funding is

The introduction of modulator therapy, particularly when its use becomes widespread, is likely to have an impact upon the range of CF phenotypes. The amount of phenotypic variations should decrease as fewer patients have significant CFTR channel dysfunctional, and it is likely that the disease manifestations will be less severe. It is well known that respiratory related CF disease is associated with less than 10% CFTR channel function and so there is the potential for modulator therapy to have an impact upon this [21]. However, measurements of the degree of change in CFTR channel functionally with the use of modulator therapy is not being undertaken in the clinical setting. The markers being assessed are all surrogate markers of CFTR channel function and include lung function, sweat chloride, weight and quality of life questionnaires. Hence, it will be interesting to see the long-term impact of significant CFTR modulation on the CF cohort when individuals have been on such treatment for many years from birth. Currently a significant improvement is felt to be an increase in ppFEV1 greater than 10%. Time will tell as to whether such changes have a significant impact upon this long-term multi-system

**46**

disease.

The advancements in CF care over the last decade have been remarkable. The use of HTS drug discovery programs have been instrumental in enabling the development of the CFTR modulator agents, first the potentiators and subsequently the corrector agents. The fact that such therapies target the underlying consequence of the CFTR mutation has led to exciting clinical outcomes for individuals with certain CFTR mutations because altering the function of the CFTR protein at the molecular level is essential for true disease change to occur. "Genetic medicines" require a significant improvement in their clinical outcomes before they can become a viable option to modulator therapy. They do however have the advantage that they are not specific for individual mutation classes and could be used as treatment for all patients.

The introduction of newer targeted therapies is transforming CF care, although it remains to be seen how these treatments will impact the CF community in the longer term. Nevertheless, a shift is starting to occur whereby treatments are determined based upon an individual's genetic mutations. It is likely that this will lead to a more personalized model of care and it is hoped a step closer to a cure for this life-limiting disease.


**Survivability under Overheating The Impact of Regional and Global Climate Change on Vulnerable and Low Income Population**

Edited by

Afroditi Synnefa, Shamila Haddad, Priya Rajagopalan and Matthaios Santamouris

Printed Edition of the Special Issue Published in *Climate*

www.mdpi.com/journal/climate


**6. Cracks: pad cratering**

Cracks occur not only in the soldered joints, but also in the components and PCB. Due to mechanical, thermal and combined stress, the material is under tension, which results in cracks forming in the weakest spot, together with a release of the tension [3].

The location of the cracks depends on many factors (the materials used, the type of soldering technology, the package, the PCB material, geometric factors, etc.) [4, 5]. **Figure 8** shows an overview of crack failures occurring in a PCB assembly.

An example of a crack in the site of the intermetallic alloy on the interface between the BGA package's terminal and the ball of solder alloy is shown in the microsection in **Figure 9**. Due to their minimum dimensions, these errors are difficult to detect using X-ray inspection.

Another example of a crack is pad cratering where a crack is formed within the PCB under the soldering pad (see **Figure 10**). This defect does not manifest during a functional electrical test, and it is not even possible to detect it with the nondestructive methods for the output check.

**125**

**Figure 10.**

A pad cratering defect can be compounded by the use of lead-free solder alloys, where the higher temperatures used for lead-free solder alloys cause greater tension in the materials used [6, 7]. In addition, the lead-free solder alloys are significantly stiffer than tin-lead eutectic solder alloys; therefore, they transfer greater stress

under the package pads during a mechanical stress [8].

*Microsection of a BGA terminal soldered to a PCB with a pad cratering defect.*

*A longitudinal crack between the solder joint and the BGA package's terminal.*

*Overview of Selected Issues Related to Soldering DOI: http://dx.doi.org/10.5772/intechopen.91023*

*Overview of crack failures occurring in a PCB assembly.*

**Figure 8.**

**Figure 9.**

*Overview of Selected Issues Related to Soldering DOI: http://dx.doi.org/10.5772/intechopen.91023*

*Welding - Modern Topics*

**Figure 6.**

**Figure 7.**

the reflowed solder alloy on the solder pad no longer joins with the reflowed BGA solder alloy ball. The Head-in-Pillow effect in connection with the temperature profile

Cracks occur not only in the soldered joints, but also in the components and PCB. Due to mechanical, thermal and combined stress, the material is under tension, which results in cracks forming in the weakest spot, together with a release of

of soldering technology, the package, the PCB material, geometric factors, etc.) [4, 5]. **Figure 8** shows an overview of crack failures occurring in a PCB assembly. An example of a crack in the site of the intermetallic alloy on the interface between the BGA package's terminal and the ball of solder alloy is shown in the microsection in **Figure 9**. Due to their minimum dimensions, these errors are dif-

The location of the cracks depends on many factors (the materials used, the type

Another example of a crack is pad cratering where a crack is formed within the PCB under the soldering pad (see **Figure 10**). This defect does not manifest during a functional electrical test, and it is not even possible to detect it with the non-

is shown in **Figure 6**, together with a photo of a microsection in **Figure 7**.

*Head-in-pillow effect in connection with the temperature profile.*

**124**

**6. Cracks: pad cratering**

*Photo of a microsection of the head-in-pillow effect.*

ficult to detect using X-ray inspection.

destructive methods for the output check.

the tension [3].

**Figure 8.** *Overview of crack failures occurring in a PCB assembly.*

#### **Figure 9.**

*A longitudinal crack between the solder joint and the BGA package's terminal.*

#### **Figure 10.** *Microsection of a BGA terminal soldered to a PCB with a pad cratering defect.*

A pad cratering defect can be compounded by the use of lead-free solder alloys, where the higher temperatures used for lead-free solder alloys cause greater tension in the materials used [6, 7]. In addition, the lead-free solder alloys are significantly stiffer than tin-lead eutectic solder alloys; therefore, they transfer greater stress under the package pads during a mechanical stress [8].

Static or cyclic mechanical stress or thermal cycling can lead to the cracks spreading and the consequent failure of the device [9]. Stress can affect a mounted PCB even without external influences; this is called residual stress (tension that remains in the material even though the cause of stress has been removed). The source of the residual stress is primarily the manufacturing process in which many stress factors affect the components [10]. This primarily concerns the soldering process, where the elevated temperature leads to the fixation of components that often have different coefficients of thermal expansion.


**7. Medical research and moving beyond individual behaviors**

Structural constrains on individuals can be medical as well as societal. Not only socioeconomic class but personal medical profiles may reveal the limits to individualistic prescriptions. Biological propensities include a mix of factors that make some children more vulnerable to obesity and its correlates. Specifically, a child's "inflammatory profile" may indicate varying levels of severity of obesity and likelihood of developing Type 2 diabetes [8].

Whereas certain individuals become obese on limited food intake, their experiences are rarely creditable, because ideas of individual accountability suggest that they must be consuming more energy than they report. Research articles with revealing titles such as "Do unsuccessful dieters intentionally underreport food intake?" [55] conclude that shame in a culture that blames obesity on the obese prompts underreporting.

Well‐studied human populations provide illustrative examples of genetic and molecular mechanisms that couple energy intake and expenditure to obesity in ways that are not strongly associated with individual‐level behaviors. The Pima aboriginal population of the states of southern Arizona in the United States and northern Sonora in Mexico are highly genetically similar and share evolutionary origins. The Sonora cohort subsists on a more traditional Mexican diet, whereas the Arizona cohort consumes a calorie‐dense US diet. The Arizona cohort experiences some of the highest rates of obesity and diabetes in the world, whereas the Sonora cohort is less obese and much healthier. Consensus medical opinion holds that these differences are related to genetics and metabolic pathways, not primarily to differences in individual willpower on either side of the border.

New studies are being proposed, to learn more from these populations about the mechanisms linking obesity and health outcomes. With chronic inflammation as a central explanatory mechanism, new types of data become relevant. For example, the nationally representative US National Social Life, Health, and Aging Project, 2005–2006, was used to investigate why older black men have worse metabolic outcomes than older white men, ages 57–85 years. Research at the intersection of social science and medicine finds that health behaviors do not explain the difference [56]:

"Instead, these outcomes seem to derive more consistently from a factor almost unexamined in the literature—chronic inflammation, arguably a biological "weathering" mechanism induced by these men's cumulative and multi‐dimen‐ sional stress. These findings highlight the necessity of focusing attention not simply on proximal behavioral interventions, but on broader stress‐inducing social inequalities, to reduce men's race disparities in health."

The insight that obese individuals who are relatively metabolically healthy (*e.g*., no Type 2 diabetes despite obesity) lack many local (in adipose tissue) and systemic (in blood) biomarkers of chronic inflammation was important [57]. The impact of such insight into medical screening and treatment protocols is surprisingly low inasmuch as many clinicians, whose training is a journey through avowedly meritocratic institutions, do not readily see beyond individual accountability for health outcomes. There is still strong medical opinion that avers that obese individuals must be both in charge of their own obesity and at risk of their somewhat deserved if unfortunate outcomes. Indeed, obesity was only recognized as a disease by the American Medical Association in 2013, over considerable opposition among professionals.

What is interesting from a translational medicine approach is that these findings meet resistance in promulgation into care management and public policy. One reason appears to be that there is a robust faith that obese people must be, to some significant degree, "responsible" for their own obesity and unhealthy as a consequence (or even, more subtly, as a punishment or cautionary tale). The possibility that some obese people might not experience high risk of comorbidities like diabetes and cardiovascular disease, whereas some lean people may in fact experience elevated risk is a provocation and a challenge to long‐held understandings. This provocation might be greeted as a bold new way to direct healthcare dollars into more carefully evidence‐based treatments of obese and lean people [53]. However, these insights run against the grain of cultural beliefs. Dominant ideas like meritocracy traverse societal domains. It is as likely that deeply held views of merit‐based outcomes prevail in the workplace as in the clinical setting.

Overall, the role of unresolved, chronic inflammation [57] in understanding childhood health risks [8] and racial disparities [56, 58] is gaining attention. The quest to characterize structural factors in addition to individual behaviors requires a shift in mindset. Individualism is defended by the corporate actors who benefit most from the current economy. Fresh perspec‐ tive is needed precisely at a time when the idea of individual accountability is gaining global traction. Individual accountability is a fundamental tenet of neoliberal capitalism and its financial institutions, which are only getting stronger [59].


**1.4 The future of natural gas**

The world is hungry for energy. On the one hand, there is a need for cheap and increasing energy, on the other hand, fossil fuels are seeing more and more resistance, and the energy sector has started its transformation.

*"Industry discussions about the future of gas in North America are polarizing. On [the] one hand, the shale revolution keeps delivering, displacing liquefied natural gas (LNG) imports since the late 2000s, as abundant gas resources and technological innovation drove costs down... On the other hand, as state-level decarbonization policies ramp up, the demand for natural gas in key segments such as power generation and local distribution companies (LDC) is expected to decline"* [15].

Natural gas can bring supply and demand of electricity into balance, by fuelling dispatchable on-demand power generation (as huge energy storage devices are lacking). There will probably be more volatility in demand for that natural gas with an increasing share of wind power and photovoltaics, which are difficult to predict in their actual production and which cannot be tuned to demand. Also, it is not yet clear how fast and how effectively the gas industry can curb its fugitive methane emissions, and which policies different countries will enact.

In any case, we are on a path of decarbonization, and times have become unsecure for natural gas owners and industry incumbents. This is not a convenient situation, and energy-related investments are typically characterized by very long (several decades) investment times.

In the near future, we might see

What can be taken for granted, owners of natural gas will be more inclined to produce value-added materials from natural gas, rather than betting on their resource being continuously used as fuel in the next decades.

Also, owners of natural gas resources that have not yet been connected to the grid might turn towards materials production, as the corresponding production plants can be economic also at smaller scale than mere natural gas extraction for energy. Depending on the value of the products, units of 10,000 tons/year of materials or less can be viable. In the transition to the bioeconomy, biorefineries face the challenge of scalability. Larger scale translates into lower unit costs, however, at the same time, raw material transport over longer distances will increase the costs, so the optimum scale is narrower than with a natural-gas operated plant.

What's more, there has been a strong technology push for gas fermentation technology from biogas gasification (to synthesis gas), which generates technology spill-over potential for natural gas fermentation. Biogas production by anaerobic digestion of various substrates [18] is an established technology.

These 3 aspects make natural gas fermentation a highly attractive route for methane valorization.


**6. Conclusions**

The evaluation in this paper illustrates the wide spectrum of interactions and possibilities for WWTPs. It is shown that the water sector is capable of taking part in sector coupling in many ways and generates multiple synergies and advantages towards a stand-alone solution of the di fferent applications. The scale of an implementation in WWTPs is mostly much lower than on an industrial level but with a transferability to a high number of suitable locations and individual solutions. For many cases, a quantitative statement from literature/reports is not transferable due to the laboratory scale. Mostly, just the opportunity and feasibility could be evaluated, but in the end, it has to be tested individually on the considered plant. First, practical implementations are realized by small, local networks taking environmental protection as a top priority for their own local policy development, even without funding.

Across all the literature, obstacles and challenges resemble one another. Technological feasibility is mostly given, but the most relevant obstacle is the lack of economic viability driven by a regulatory framework that does not fit to a fast-changing energy environment. That relates, e.g., to Germany, from not fitting the taxation treatment of energy storage systems and power purchases to inconsequential funding mechanisms and other regulatory backgrounds, which lag behind the technological progress for a fast energy transition [6]. There is a need for establishing a framework for sector coupling regarding the special, manifold and complex interactions of the many a ffected sectors with each other. This includes a further development and coordination of norms and standards across the national level as well.

Furthermore, WWTP operators have to be supported in day-to-day businesses to handle additional tasks caused by sector coupling. Key objectives of the plants will always be treating wastewater as the main priority. Especially, smaller WWTPs are often not able to provide the needed financial and human resources for additional activities in such a variety of tasks outside the usual disciplines. New business models for operating innovative technologies have to be found and to make use of as much of the synergies as possible. WWTPs would switch from locations of just treating wastewater to local energy and resource facilities, with all their benefits and drawbacks. In conclusion, the water sector is a notable and reasonable player in the field of sector coupling, especially in times of changes to a renewable energy system.

#### **7. Outlook and Further Approach**

To implement such innovative technologies in WWTPs, a holistic analysis of the available resources on the plant is necessary, e.g., energy production, flexibility options and gas flow rates. These have to match with the surrounding infrastructure (industry, public transportation system and energy grids) and the energetic environment (local heat demands, available energy surplus, etc.). For the Mainz WWTP (400,000 PE120; Germany), a wide-range sector-coupling analysis was carried out, which includes an overall analysis followed by a detailed feasibility study for the most promising results [65,66]. In the following, based on these conductions, the findings that are necessary to prepare and realize such an implantation are presented:

Assembling a responsible interdisciplinary team is therefore a prerequisite for working on such a diversified project. This includes at least one of the following experts: general planner for large construction measures, plant operator, energy supplier, grid operator, scientific support and various engineering expertise depending on the targeted sectors. This team should develop a practicable and technical-economic feasible concept based on the local situation. After selecting and specifying a preferred variant to be implemented, the funding situation needs to be clarified before finally deciding on the implementation.

In the meantime, at the Mainz WWTP, the political and technical decision-maker has given their consent, and the positive notification of federal funding has arrived. The project will start in 2020 with further regulatory preparations, assessments and the invitation of tenders. The start of implementation is planned for 2021.

**Author Contributions:** Conceptualization, M.S.; methodology, M.S.; formal analysis, M.S. and O.G.; investigation, M.S. and O.G.; writing—original draft preparation, M.S.; writing—review and editing, M.S., O.G. and H.S.; supervision, H.S.; All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

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


**1. Introduction**

Current iron and steel-making industries are experiencing challenges, such as lowgrade ore (<35% iron), poor sintering performance, and CO2 gas emissions. FASTMET, ITmk3, and Hi-QIP processes can be adopted to increase the iron concentration of low-grade ores. For such processes, a mixture of powdery iron ore and carbonaceous material is used as raw materials, whereas the conductive heat flow from the surface to the interior of materials is the rate-controlling step, resulting in decreased productivity. The demand for microwave heating is escalating day by day in iron-making industries owing to its faster heating rate, volumetric heat generation for specific materials, energy savings, and less processing time [1–7]. Hematite can be converted to magnetite for iron ore beneficiation purposes. It can be achieved by heating the hematite. There are two ways of heating: one, conventional heating, and

second, microwave heating. In any conventional heating processes, along with hematite, other impurity oxides will be heated, which is not beneficial. This unnecessary heating can be bypassed by adopting microwave heating. In microwave heating, high efficiency in heating can be achieved because not all impurity oxides are heated, such as SiO2 and Al2O3 [8]. Hayashi et al. [7] experimentally generated temperature versus time profile and predicted the effect of graphite content on the temperature characteristic of a mixture of hematite and graphite powders. Standish and Huang [9] investigated the reduction behaviors of hematite fines by mixing carbon and suggested microwave reduction in a non-isothermal process, and the temperature had a significant impact on the reduction of hematite fines. Agrawal and Dhawan [10] evaluated the reduction behavior of low iron hematite ore containing coke and charcoal and reported coke to be a better reductant than charcoal. Mishra and Roy [11] introduced carbon content that had an important effect on the reduction efficiency of the iron ore–coal composite pellet. They [11] obtained a 70% degree of reduction at 1250o C for 20 minutes when the C to Fe2O3 molar ratio is three. Zhulin et al. [12] presented the effect of carbon content on the reduction efficiency of iron ore–coal composite pellets at 1200°C for 15 minutes and predicted that higher carboncontaining pellets reduced faster than lower carbon containing pellets. Mourao et al. [13] have demonstrated the reduction rate and maximum temperature of process depending upon the fraction of carbonaceous material. The authors found that if the fraction of carbonaceous material increases in the mixture of hematite ore and carbonaceous material, the maximum temperature increases in the process, which increases the reduction reaction rate of hematite ore. Mishra et al. [14] developed a thermal profile considering powder size, emissivity, and susceptibility using microwave heating, and reported that the model predictions were in good agreement with experimental results. The previous studies [7–14] experimentally demonstrated coke or coal to have a significant effect on temperature and reduction rate of hematite ore. However, their work lacks temperature distribution during the process. Shukla et al. [15] simulated temperature distribution in 2D cylinders of varying radii and physical properties using an explicit infinite method and found that the efficacy of temperature distribution in cylinders depends on the sample size and its thermal conductivity. They considered constant thermal conductivity and heat capacity throughout the process. Peng et al. [16] have demonstrated the heat transfer numerically during microwave heating of magnetite 1D slab. They solved the heat equation using an explicit infinite method based on fewer dimensions. Peng et al. [17] predicted the dielectric and magnetic behavior of the nonstoichiometric ferrous oxide at 823 K and 1373 K, respectively, and evaluated the temperature dependence of the microwave absorption capability of the ferrous oxide by considering the phase transformation during heating. Leo et al. [18] have shown effective permittivity of soils using Lichtenecker's mixing model. Although microwaves have superiority in materials heating, a major drawback known as nonuniform temperature distribution inside materials has also been observed [5, 6]. To address this problem, accurate temperature determination inside the materials under microwave irradiation is necessary. For last 30 years, microwave heating has been utilized extensively in the food processing industry. Most of those works considered heat diffusion and/or convection to predict the temperature distribution in the material.

Although a lot of work has been done on microwave heating, the present study investigates the heat transfer process in microwave heating to predict the temperature distribution inside a 1D hematite slab using an implicit finite-difference approach by considering heat diffusion convection and radiation effects. The objective of the

*Simulation Study of Microwave Heating of Hematite and Coal Mixture DOI: http://dx.doi.org/10.5772/intechopen.106312*

current study is to design and produce a well-defined heating profile in a 1D rectangular slab of hematite ore using microwave heating routes. The resulting temperature profile can be used as a guiding tool to optimize the carbothermal reduction process of hematite in industry, where we studied on large slab (20 cm x 20 cm) as well as laboratory approach small slab (1 cm x 1 cm).


**Techno Economic Evaluation of Cold Energy from Malaysian Liquefied Natural Gas Regasification Terminals**

### **Mohd Amin Abd Majid 1,\*, Hamdan Haji Ya 1, Othman Mamat 1 and Shuhaimi Mahadzir 2**

Received: 3 October 2019; Accepted: 20 November 2019; Published: 24 November 2019

**Abstract:** In order to cater for increased demand for natural gas (NG) by the industry, Malaysia is required to import liquid natural gas (LNG). This is done through PETRONAS GAS Sdn Bhd. For LNG regasification, two regasification terminals have been set up, one in Sungai Udang Melaka (RGTSU) and another at Pengerang Johor (RGTPJ). RGTSU started operation in 2013 while RGTPJ began operation in 2017. The capacities of RGTSU and RGTPJ are 3.8 (500 mmscfd) and 3.5 (490 mmscfd) MTPA, respectively. RGTSU is an offshore plant and uses an intermediate-fluid-vaporization (IFV) process for regasification. RGTPJ is an onshore plant and employs open-rack vaporization (ORV). It is known that a substantial amount of cold energy is released during the regasification process. However, neither plant captures the cold energy released during regasification. This techno economic study serves to evaluate the technical and economic feasibility of the cold energy available during regasification. It was estimated that approximately 47,214 and 88,383 kWh of cold energy could be generated daily at RGTPJ and RGTSU, respectively, during regasification processes. Converting this energy into RTh at 70% thermal efficiency, and taking the commercial rate of 0.549 Sen per RTh, for the 20-year project life, an internal rate of return (IRR) of up to 33% and 17% was estimated for RGTPJ and for RGTSU, respectively.

**Keywords:** liquefied natural gas; cold energy; regasification; chilled water; techno economic


*3.6.3 Soaking seeds in EM*

Seeds are soaked in 0.1% EM water before planting. Smaller species are soaked for 30 minutes, while the bigger species are soaked for up to 6 hours. Seeds are then dried under the shade to reduce the chances of sticking together [3, 35, 36] and planted in the field.


**ADVANCES IN GLASS SCIENCE AND TECHNOLOGY**

#### **Advances in Glass Science and Technology**

http://dx.doi.org/10.5772/intechopen.69580 Edited by Vincenzo M. Sglavo

#### **Contributors**

Kadir Bilisik, Gaye Kaya, Hüseyin Özdemir, Gulhan Erdogan, Mahmut Korkmaz, Jihui Yuan, Uwe Petzold, Montri Suklueng, Hongwei Guo, Josefina Alvarado-Rivera, Carlos Guadalupe Pérez Hernández, María Elena Zayas Saucedo, Mario Alvarez-Ramos, Quanlong He, Pengfei Wang, Min Lu, Bo Peng, Limbraj Spoan Ravangave, Ganesh Devde, Nguyen Van Toan, Naoki Inomata, Masaya Toda, Takahito Ono, Daniel Milanese, Joris Lousteau, Xiushan Zu, Arturo Chavez-Pirson, Nadia G. Boetti, Diego Pugliese, Nasser Peyghambarian

#### **© The Editor(s) and the Author(s) 2018**

The rights of the editor(s) and the author(s) have been asserted in accordance with the Copyright, Designs and Patents Act 1988. All rights to the book as a whole are reserved by INTECHOPEN LIMITED. The book as a whole (compilation) cannot be reproduced, distributed or used for commercial or non-commercial purposes without INTECHOPEN LIMITED's written permission. Enquiries concerning the use of the book should be directed to INTECHOPEN LIMITED rights and permissions department (permissions@intechopen.com). Violations are liable to prosecution under the governing Copyright Law.

Individual chapters of this publication are distributed under the terms of the Creative Commons Attribution 3.0 Unported License which permits commercial use, distribution and reproduction of the individual chapters, provided the original author(s) and source publication are appropriately acknowledged. If so indicated, certain images may not be included under the Creative Commons license. In such cases users will need to obtain permission from the license holder to reproduce the material. More details and guidelines concerning content reuse and adaptation can be foundat http://www.intechopen.com/copyright-policy.html.

#### **Notice**

Statements and opinions expressed in the chapters are these of the individual contributors and not necessarily those of the editors or publisher. No responsibility is accepted for the accuracy of information contained in the published chapters. The publisher assumes no responsibility for any damage or injury to persons or property arising out of the use of any materials, instructions, methods or ideas contained in the book.

First published in London, United Kingdom, 2018 by IntechOpen eBook (PDF) Published by IntechOpen, 2019 IntechOpen is the global imprint of INTECHOPEN LIMITED, registered in England and Wales, registration number: 11086078, The Shard, 25th floor, 32 London Bridge Street London, SE19SG – United Kingdom Printed in Croatia

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**9.3 Role of ECMO in nonacute myocardial infarction cardiogenic shock**

Patients with acute heart failure (HF) who present in CS have high mortality. Conventional HF therapies including optimal medical management, inotropes, vasopressors, and IABP are the initial line of management. However, patients who fail to respond to medical management may benefit from VA-ECMO. It is indicated in patients with medically refractory CS and in patients at high risk of cardiogenic shock as determined by scoring systems such as CardShock risk score and IABP-SHOCK II risk scores. ECMO is also AMCS of choice in patients with CS who have biventricular failure, respiratory failure, life-threatening arrhythmias, or cardiac arrest. There is often an overlap between indications for ECMO and AMCS devices. However, patients with CS who have associated respiratory failure are best managed by ECMO [106, 107]. The outcome of ECMO in patients with HF varies significantly depending on the etiology. The survival after hospital discharge for patients managed with ECMO is 71.9% for myocarditis [108], 74.3% for patients with primary graft failure post-heart transplant [109], and 42% one-year survival for patients with acute decompensation of chronic cardiomyopathy. However, patients aged >75 years, patients with severe neurological injury, multiple organ failure, and multiple comorbidities are risk factors for adverse outcomes. Dangers et al. also reported poor outcomes of ECMO in patients with SOFA scores >13 prior to ECMO cannulation [110].

The role of ECMO in these patients varies depending upon the etiology and can be a bridge to recovery, bridge to transplant, bridge to left ventricular assist device (VAD), or bridge to decision [111].

*Overview of Venoarterial Extracorporeal Membrane Oxygenation (VA-ECMO) Support… DOI: http://dx.doi.org/10.5772/intechopen.105838*


**3. Association between anti-HLA donor-specific antibodies and transplant outcomes (Table 1)**

Despite technological advances in detecting pre-transplant DSA, the incidence of acute and chronic AMR appears to increase over time. However, the true incidence of AMR remains

unclear with suggestions that acute AMR may account for up to 7% of all acute rejections (and up to 50% of acute rejection episodes experienced by pre-sensitized patients with positive cross-match); whereas the prevalence of chronic AMR manifesting as transplant glomerulop‐ athy may be as high as 20% at 5 years post-transplant [19, 20]. The growing incidence may be attributed to a number of plausible reasons including: greater acceptance of highly-sensitized candidates for transplantation, the use of non-calcineurin-inhibitor-based immunosuppres‐ sive regimen such as mammalian target of rapamycin inhibitors, better detection techniques for DSA, availability of markers of antibody injury such as C4d staining and a greater under‐ standing of AMR, which may have been misinterpreted as chronic allograft nephropathy or

Detection of Antibody-Mediated Rejection in Kidney Transplantation and the Management of Highly Sensitised…

http://dx.doi.org/10.5772/54735

111

In most countries, a large proportion of renal transplant candidates on the transplant waitlist are sensitized with high PRA levels and have multiple anti-HLA antibodies, which often result in protracted wait-list time [22]. In Australia, 23% of transplant candidates have a peak class I PRA of >20% and these sensitized transplant candidates often have twice as long a waiting time as unsensitized candidates [23]. Pre-transplant DSA is a major immunologi‐ cal hurdle for successful kidney transplantation. The clinical importance of pre-transplant DSA has been clearly established over the past decade and the presence of high levels of pre-transplant class I (HLA-A and B) ± II (HLA-DR) DSA, typically occurring as a result of prior sensitizing events including previous blood transfusions, HLA-mismatched trans‐ plants and/or pregnancy, is associated with inferior graft outcomes, including an increased risk of developing acute and chronic antibody-mediated rejection (AMR), transplant glomer‐ ulopathy and late graft loss (Table 1) [24-27]. However, few studies have suggested that the association between pre-transplant DSA and graft survival was restricted to recipients who had developed early AMR or those with high levels of DSA as determined by peak HLA-DSA strength expressed as mean fluorescent intensity (MFI) using Luminex technology and that pre-transplant screening for preformed DSA may not be cost-effective [28, 29]. *Lefau‐ cheur C et al* demonstrated in a large single centre study that renal transplant recipients with a peak pre-transplant DSA >465 MFI determined by Luminex have a significantly higher risk of developing AMR and that recipients with peak DSA >3000 have almost a four-fold increase in the risk of graft loss compared to recipients with peak DSA MFI of <3000 high‐ lighting the importance of using DSA strength to more accurately assess the immunological risk of transplant recipients [29]. There is also increasing evidence demonstrating that the development of *de novo* DSA may occur in over 50% of renal transplant recipients at 2-years post-transplant suggesting that regular monitoring of de novo DSA post-transplant may help identify those at risk of developing poorer graft outcome [30]. Several studies have shown that the development of *de novo* DSA (occurring post-transplantation), especially DSA directed against HLA-DQ graft molecules in HLA-class II incompatible graft transplan‐ tations, are both associated with acute and subclinical AMR and graft loss in kidney trans‐ plant only and/or simultaneous pancreas-kidney transplant recipients and post-transplant monitoring of DSA could potentially help clinicians to individualize the amount of immuno‐

undefined rejection in the past [21].

HLA – human leukocyte antigen, DD – deceased donor, LD – live-donor, CDC-XM – complement dependent cytotoxicity cross-match, DSA – donor-specific antibodies, SAB – single antigen bead, AMR – antibody mediated rejection, DCGS – death-censored graft survival, MFI – mean fluorescent intensity, BPAR – biopsy-proven acute rejection, PPV – positive predictive value.

**Table 1.** Association between pre-transplant donor-specific antibodies and graft outcomes.

unclear with suggestions that acute AMR may account for up to 7% of all acute rejections (and up to 50% of acute rejection episodes experienced by pre-sensitized patients with positive cross-match); whereas the prevalence of chronic AMR manifesting as transplant glomerulop‐ athy may be as high as 20% at 5 years post-transplant [19, 20]. The growing incidence may be attributed to a number of plausible reasons including: greater acceptance of highly-sensitized candidates for transplantation, the use of non-calcineurin-inhibitor-based immunosuppres‐ sive regimen such as mammalian target of rapamycin inhibitors, better detection techniques for DSA, availability of markers of antibody injury such as C4d staining and a greater under‐ standing of AMR, which may have been misinterpreted as chronic allograft nephropathy or undefined rejection in the past [21].

**Study Cohort Rejection Graft survival**

(p=0.01)

glomerular rejection

categorized by MFI: MFI <465 – prevalence 1% MFI 466 to 3000 – prevalence 19% MFI 3001 to 6000 – prevalence 36% MFI >6000 – prevalence 51% Peak DSA MFI predicted AMR better

than current DSA MFI

Incidence AMR 31%

greater risk of AMR

vs >9500 36%

negative 35%

0%

**Table 1.** Association between pre-transplant donor-specific antibodies and graft outcomes.

Total MFI and AMR: <9500 7%

Class II DSA but not class I DSA

Overall incidence of clinical/subclinical rejection including AMR and/or acute Tcell mediated rejection at day 200 posttransplant: DSA-positive 71% vs DSA-

BPAR: DSA-positive 56% vs DSA-negative

Class II > class I DSA higher incidence of AMR: 100% vs 22% Class II DSA MFI of 4487 predicted AMR with sensitivity of 100% and specificity of 87%.

HLA – human leukocyte antigen, DD – deceased donor, LD – live-donor, CDC-XM – complement dependent cytotoxicity cross-match, DSA – donor-specific antibodies, SAB – single antigen bead, AMR – antibody mediated rejection, DCGS – death-censored graft survival, MFI – mean fluorescent intensity, BPAR – biopsy-proven acute rejection, PPV – positive

vs no DSA 3% (p < 0.001)

Vascular: 19% T-B- XM vs 32% T-B+ XM

Graft loss: T-B+ 44% vs T-B-

Non-sensitized - 89% and 84% Sensitized with no DSA - 92%

DSA-positive - 71% and 61 Relative risk for graft loss if AMR 4.1 (95% CI 2.2 to 7.7) vs

Overall graft survival at 8 years:

Graft survival lower in patients with DSA and AMR compared to DSA and no AMR and in non-DSA patients

3-year graft survival was 100% for total MFI <9500 vs 76% for

5-year DCGS: No DSA 89% vs DSA without AMR 87% vs DSA

No difference in graft survival

DSA-positive 68% DSA-negative 77%

total MFI >9500.

with AMR 68%

5 and 8-year DCGS:

and 92%

no AMR

27%

DSA+ significantly predict vascular or

PPV for AMR with peak DSA 35% vs current DSA 32% Prevalence of AMR

Incidence of AMR: preformed DSA 35%

*Eng H et al* [24]

*Lefaucheur C et al* [25]

*Lefaucheur C et al* [26]

*Mujtaba M et al* [34]

*Amico P et al* [94]

*Song EY et al* [95]

predictive value.

N=471 DD renal transplant

110 Current Issues and Future Direction in Kidney Transplantation

83 T-B+ XM vs 386 T-B- XM IgG DSA in 33% of T-B+ XM

N=402 DD renal transplant

Peak sera: positive DSA 21%

N=237 LD/DD renal transplant

All negative T and B-cell

27% class I or II anti-HLA antibody with 52% anti-HLA antibody being DSA

N=44 desensitized LD transplant recipients Negative CDC T-cell XM Sensitization = CDC B+ & T+ ± B+ flow XM

N=334 LD and DD renal transplant recipients 332 negative T and B cell CDC-XM 67 DSA vs 267 no DSA

N=28 LD and DD renal transplant recipients Positive flow XM but negative CDC-T cell XM, 57% positive DSA

(Luminex)

Current sera: positive

recipients

patients

recipients

(Luminex)

DSA 19%

recipients

CDC-XM

In most countries, a large proportion of renal transplant candidates on the transplant waitlist are sensitized with high PRA levels and have multiple anti-HLA antibodies, which often result in protracted wait-list time [22]. In Australia, 23% of transplant candidates have a peak class I PRA of >20% and these sensitized transplant candidates often have twice as long a waiting time as unsensitized candidates [23]. Pre-transplant DSA is a major immunologi‐ cal hurdle for successful kidney transplantation. The clinical importance of pre-transplant DSA has been clearly established over the past decade and the presence of high levels of pre-transplant class I (HLA-A and B) ± II (HLA-DR) DSA, typically occurring as a result of prior sensitizing events including previous blood transfusions, HLA-mismatched trans‐ plants and/or pregnancy, is associated with inferior graft outcomes, including an increased risk of developing acute and chronic antibody-mediated rejection (AMR), transplant glomer‐ ulopathy and late graft loss (Table 1) [24-27]. However, few studies have suggested that the association between pre-transplant DSA and graft survival was restricted to recipients who had developed early AMR or those with high levels of DSA as determined by peak HLA-DSA strength expressed as mean fluorescent intensity (MFI) using Luminex technology and that pre-transplant screening for preformed DSA may not be cost-effective [28, 29]. *Lefau‐ cheur C et al* demonstrated in a large single centre study that renal transplant recipients with a peak pre-transplant DSA >465 MFI determined by Luminex have a significantly higher risk of developing AMR and that recipients with peak DSA >3000 have almost a four-fold increase in the risk of graft loss compared to recipients with peak DSA MFI of <3000 high‐ lighting the importance of using DSA strength to more accurately assess the immunological risk of transplant recipients [29]. There is also increasing evidence demonstrating that the development of *de novo* DSA may occur in over 50% of renal transplant recipients at 2-years post-transplant suggesting that regular monitoring of de novo DSA post-transplant may help identify those at risk of developing poorer graft outcome [30]. Several studies have shown that the development of *de novo* DSA (occurring post-transplantation), especially DSA directed against HLA-DQ graft molecules in HLA-class II incompatible graft transplan‐ tations, are both associated with acute and subclinical AMR and graft loss in kidney trans‐ plant only and/or simultaneous pancreas-kidney transplant recipients and post-transplant monitoring of DSA could potentially help clinicians to individualize the amount of immuno‐ suppression to better assess immune reactivity [25, 30-33]. Although there is no current con‐ sensus on the level of clinically significant DSA identified by flow cytometric or Luminex assays, most studies have demonstrated that increasing single, peak or total DSA levels were associated with an incremental risk of rejection and/or graft loss [29, 34]. Recent stud‐ ies have suggested that the detection of C1q-fixing DSA (i.e. the potential to identify DSA that can activate complements by binding C1q) may be more accurate in predicting acute rejection, biopsy C4d-deposition, transplant glomerulopathy and late graft failure following kidney transplantation and the authors suggested that the absence of C1q-positive de novo DSA has a high negative predictive value for transplant glomerulopathy (100%) and graft failure (88%) [35]. However, a recent retrospective study showed that the identification of strong complement-activating DSA (of IgG subclasses 1 and 3) pre-transplant was unlikely to improve AMR risk stratification compared to patients with a combination of both strong and weak/no complement-activating DSA (of IgG subclasses 2 and 4) [36]. The clinical im‐ portance of C1q-specific DSA in predicting graft outcome remains controversial and not routinely performed in many transplanting centres [35, 37]. With the greater understanding of HLA antigens and anti-HLA antibodies, innovative techniques have been established to allow transplantation across positive CDC and/or flow cross-match barriers by removing circulating DSA and/or B or plasma cells and the success and outcomes of these initiatives will be discussed later in this chapter.

**Antibodies HLA-**

Anti-angiotensin type 1–receptor antibody

Anti-endothelial cell antibody [39,99]

Glutathione-S-transferase

Antibodies to MIG (also called CXCL9), ITAC (also called CXCL11), IFN-γ, and glial-derived neurotrophic

factor [103]

Anti-HLA-Ia antibody [105]

Protein kinase Czeta antibody [104]

HLA – human leukocyte antigen

T1 antibody [40]

[96,97]

**antigen (Yes/No)**

MICA antibody [98] Yes Major histocompati-

Vimentin antibody [100] No Intermediate filament

Agrin antibody [101] No Highly purified GBM

Anti-GBM antibody [102] No Alpha-3 chain (the

No Angiotensin type I

ELISA)

(Luminex)

precursors (flow cytometry)

heparan sulphate proteoglycans (ELISA)

transferase T1 enzyme

Goodpasture antigen) and alpha-5 chain of type IV collagen (ELISA)

protein (flow cytometry)

No Endothelial cell

No Glutathione-S-

(ELISA)

No Chemokine or cytokine (ELISA)

(microarray)

No Protein kinase

receptor (cell-based

bility-complex class I related chain A antigens

**Target antigen Location Transplant outcomes**

Detection of Antibody-Mediated Rejection in Kidney Transplantation and the Management of Highly Sensitised…

Endothelial cells (also fibroblasts, epithelial cells)

Circulating proteins

Kidney and lymphocytes

Yes HLA-Ia alleles Endothelial cells Correlate with poorer graft

Abbreviations: MICA – major histocompatibility complex class I chain-related gene A, ACR – acute cellular rejection, AMR – antibody mediated rejection, GBM – glomerular basement membrane, ELISA – enzyme-linked immunosorbent assay,

**Table 2.** Association between non-HLA-DSA and non-HLA antibodies and renal transplant outcomes.

Endothelial cells Increased risk of ACR, vascular

hypertension

Endothelial cells Increased risk of acute and

Endothelial cells Increased risk of rejection

GBM Increased risk of transplant glomerulopathy

Endothelial cells Increased risk of C4d-negative

GBM Increased risk of vascular

acute and chronic AMR

rejection (Alport patients)

Association with chronic renal

Increased risk of graft loss

survival, possibly mediated via anti-HLA-E IgG antibody

allograft injury

chronic rejections

rejection and AMR ± malignant

http://dx.doi.org/10.5772/54735

113

Increased risk of rejection and graft failure, remains debatable