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Objective: To study the prevalence of low‐level viraemia (LLV) and its association with virological failure (VF). Methods: We conducted a retrospective analysis of 3498 participants at YRG CARE, Chennai, India (2013–2018) on antiretroviral therapy (ART) for ≥6 months with two or more plasma viral load (pVL) measurements. Results were stratified for those with pVL <1000 copies/mL: fully suppressed (FS) (pVL <40), low‐LLV (pVL 40–199), mid‐LLV (pVL 200–399), and high‐LLV (pVL 400–999). The study assessed the association with VF (pVL >1000 copies/mL) using Cox proportional hazard model. Results: Among 3498 participants, 2965 (84.8%) were FS and 533 (15.2%) were LLV. During the follow‐up, 348 (10%) experienced VF, with 222 (6.3%) experienced after LLV (42% of LLV) and 126 (3.6%) experienced after FS (4.3% of FS). When compared with FS, those with LLV had a greater risk of VF [adjusted hazard ratio (aHR) = 12.7; 95% confidence interval (CI): 10.2–15.9]. First‐line participants had a higher VF incidence (aHR = 15.8, 95% CI: 11.4–21.9) than second‐line participants (aHR = 5.6, 95% CI: 4.1–7.7). Those with high‐LLV had the highest VF risk (aHR = 22.856, 95% CI: 15.204–34.359 vs. aHR = 8.186, 95% CI: 5.564–12.043, for first‐line vs. second‐line participants, respectively), followed by those with mid‐LLV (aHR = 13.375, 95% CI: 8.327–21.483 vs. aHR = 6.261, 95% CI: 4.044–9.695) and low‐LLV (aHR = 12.976, 95% CI: 7.974–21.118 vs. aHR = 4.158, 95% CI: 2.826–6.119). Conclusions: The prevalence of LLV was intermediate in our study population. There was a higher risk of VF among individuals with LLV, and this risk increased with the increasing levels of LLV. Close monitoring of individuals experiencing LLV could help in the early identification of VF. [ABSTRACT FROM AUTHOR]

Microcombustors are microscale combustion devices that can be used to power microelectromechanical systems. Many combustor configurations are reported in the literature and, among them, combustion in a microscale recirculating heat exchanger is a feasible option. In this work, a simple, double‐channel, recirculating heat exchanger is considered. The novelty of the present work lies in the heat transfer analysis approach to design a microcombustor. A combustor is designed using thermal resistance networks for a premixed fuel containing a methane–air mixture in stoichiometric ratio. The length of the combustor is designed based on the position of the combustion flame. Computational fluid dynamics is utilized to validate the theoretical results. The analysis is carried out for adiabatic and nonadiabatic conditions. The combustor lengths for adiabatic and nonadiabatic (ceramic) combustors vary from 39 to 242 mm and 49 to 276 mm, respectively, for variations in the mass flow rate of the premixed gases from 6 to 10 mg/s. A minimum limiting flow rate of 6 mg/s was identified. The average error in the maximum combustion gas temperatures between the theoretical and CFD results obtained in this work is 4.2%. The theoretical approach presented can be suitably applied to more complex geometries involving multichannels and variations in geometrical properties. [ABSTRACT FROM AUTHOR]

The current research investigates the impact of a split fueling strategy combined with several flow rates of exhaust gas recirculation (EGR) on the combustion and emission characteristics of a diesel engine running on B20 waste cooking oil (WCO) biodiesel. A four‐stroke single‐cylinder common rail direct injection engine was employed for experiments. It operates with a B20 blend of WCO biodiesel at 600 bar pressure for varying pilot fueling conditions of 10%, 20%, and 30%. The B20 blend with 30% pilot fuel injection (B20P30) showed excellent performance and emission characteristics compared with B20 blend with 10% pilot fuel injection (B20P10) and B20 with 20% pilot fuel injection (B20P20). However, B20P30 had greater levels of nitrogen oxide (NOx) emissions than those by diesel. EGR discharge levels in 5% increments, ranging from 0% to 15% were introduced to address this issue. The experimental findings revealed that both cylinder peak pressure and heat release rate showed a reduction when the EGR flow rate was enhanced. The recirculation of exhaust gas into the combustion chamber led to a slight increase in the emission levels of hydrocarbon (HC), carbon monoxide (CO), and smoke, as well as a decrease in carbon dioxide (CO2). Nevertheless, the introduction of EGR significantly decreased NOx emissions by 22.94%, 35.05%, and 47.96% for EGR flow rates of 5%, 10%, and 15%, respectively, when compared with the engine operating without EGR. Overall, the two‐stage fueling strategy, B20P30 blended with 10% EGR corroborated to be beneficial in reducing NOx emissions with minimal performance penalties. Although there was a slight uptick in certain emissions, the overall trade‐off between emission reduction and performance was favorable. The culmination of this study is targeting the objectives of sustainable development goal 7 (clean energy) and goal 13 (climate action) to be achieved by 2030. [ABSTRACT FROM AUTHOR]

Introduction: Severe COVID‐19 infections increase the risk of thrombotic events and Intensive Care Units reported increased extracorporeal circuit clotting (ECC) in COVID‐19 patients with acute kidney injury. We wished to determine whether hemodialysis (HD) patients with COVID‐19 also have increased risk of circuit clotting. Methods: We reviewed coagulation studies and HD records, 4 weeks before and after COVID‐19 polymerase chain reaction detection in HD patients between April 2020 and June 2021. Findings: Sixty‐eight (33.5%) of 203 HD patients with COVID‐19, 65% male, mean age 64.9 ± 15.3 years, experienced some circuit clotting, and no clotting recorded prior to positive test results. In those who experienced ECC, prothrombin, activated partial thromboplastin or thrombin times were not different, whereas median factor VIII (273 [168–419] vs. 166 [139–225] IU/dl, p < 0.001), D‐dimers (2654 [1381–6019] vs. 1351 [786–2334] ng/ml, p < 0.05), and fibrinogen (5.6 ± 1.4 vs. 4.9 ± 1.4 g/L, p < 0.05) were greater. Antithrombin (94 [83–112] vs. 89 [84–103] IU/dl), protein C (102 [80–130] vs. 86 [76–106] IU/dl), protein S (65 [61–75] vs. 65 [52–79] IU/dl) and platelet counts (193 [138–243] vs. 174 [138–229] × 109/L) did not differ. On multivariable logistic analysis, circuit clotting was associated with log factor VIII (odds ratio [OR] 14.8 (95% confidence limits [95% CL] 1.12–19.6), p = 0.041), fibrinogen (OR 1.57 [95% CL 1.14–21.7], p = 0.006) and log D dimer (OR 4.8 [95% CL 1.16–12.5], p = 0.028). Discussion: Extracorporeal circuit clotting was increased within 4 weeks of testing positive for COVID‐19. Clotting was associated with increased factor VIII, fibrinogen and D‐dimer, suggesting that the risk of circuit clotting was related to the inflammatory response to COVID‐19. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) is an excellent oxidant carrier that finds its use in combustion and fuel applications. In the present study, H2O2 (30% assay) is used as an emulsifier in waste cooking oil biodiesel blend (B20) and the emissions and performance in a compression ignition engine are assessed. Along with the neat B20, three blends of B20 with 0.5%, 1%, and 1.5% H2O2 concentrations are used. Increasing the concentration of H2O2 beyond 1.5% resulted in vapor lock in the fuel pump leading to a loss in injection pressure. An increase in the exhaust gas temperature was recorded with the increase in H2O2 concentration due to improved fuel properties, like, cetane number, thermal conductivity, and microexplosions of fuel droplets. However, NOx emissions decreased mainly due to the presence of the hydroperoxyl group from H2O2. Analysis of variance was also carried out to assess the statistical significance of H2O2 on the responses and is seen that the maximum impact of H2O2 was positively influencing brake thermal efficiency (BTE), brake‐specific fuel consumption (BSFC), hydrocarbon (HC), and NOx. Compared with the B20 blend, H2O2 emulsified fuel with a concentration of 1.5% showed a substantial reduction of 53.7%, 28.6%, 14.2%, and 16.2% in the average emissions of CO, HC, smoke, and NOx, respectively. Similarly, 7.9% and 7.1% improvement in the BTE and BSFC is obtained. However, more studies are required to ascertain the NOx reduction mechanism and address issues of fuel vaporization at higher concentrations of H2O2. [ABSTRACT FROM AUTHOR]

In the present study, the dimensions of the cylindrical turbulators have been optimized to achieve the highest thermal performance. A double pipe heat exchanger with cylindrical turbulators placed in the annulus side is modeled and a numerical simulation is carried out for different operating conditions. The simulation is conducted for different diameters of the turbulators for various Re for the annulus fluid. The Nusselt number (Nu), friction factor (f), and thermohydraulic performance index (THPI) are the responses simulated for the above different cases of input conditions. Response surface methodology has been used to study the influence of operating parameters on the responses. It is observed that Nu, f, and THPI increased as the Re and turbulator diameter increased. Response optimizer is used to optimize the turbulator diameter to obtain the highest thermal performance in terms of highest Nu and THPI and lowest f. The results indicated that maximum performance was obtained for a diameter of 4.45 mm and for a Re of 5530. The Nu and THPI corresponding to the above combinations are 68.4 and 2, respectively. [ABSTRACT FROM AUTHOR]

This paper proposes an innovative precast through‐girder system that can be used in shallow bridge structures. It discusses various components of the through‐girder system, including the edge (through) girders, transverse beams, and longitudinal and transverse connections. The through girders are made of precast concrete box beam segments that are spliced longitudinally through posttensioning. The precast prestressed transverse beams span between the through‐girders involving the use of transverse posttensioning. An important feature of this system is to implement ultra‐high performance concrete (UHPC) at the all joints. The use of UHPC allows to minimizing the joint width and achieving superior durability. A numerical example is presented to demonstrate the analysis and design of the through‐girder bridge superstructure accounting for both high‐performance concrete (HPC) and UHPC options. The UHPC superstructure option can reduce the sizes of the structural members and allow to enhancing the structural performance. [ABSTRACT FROM AUTHOR]

Background: Mycosis fungoides (MF), the commonest primary cutaneous T‐cell lymphoma, has classic and variant types which include hypopigmented MF (HMF). Previous studies have identified distinct clinicopathological profiles in HMF. This study aims to objectively compare the clinicopathological features of HMF with non‐HMF lesions in order to characterize salient features of HMF. Methods: This cross‐sectional, retrospective study analyzed biopsy specimens of 87 patients with MF. HMF and non‐HMF groups were compared using clinical data, immunophenotypic features and scores given for six histopathological features: dermal infiltrate, basilar and superficially extending epidermotropism, Pautrier microabscesses and dermal and epidermotropic lymphocytic atypia. Results: Seventy‐six patients had HMF. Presentation in females (59.21%; p =.04) and patch stage (88.16%; p =.01) in HMF were significant, and HMF presented at a younger mean age when compared to non‐HMF. Both groups had equal intensity of epidermotropism, with HMF showing milder dermal infiltrates and significantly less dermal atypia. Pautrier microabscesses were significantly commoner in non‐HMF (LR 10.76; p <.01). 94.74% of HMF were CD4−/CD8+. Conclusion: HMF presents at a lower age and earlier stage with female predominance compared to non‐HMF. Because of milder dermal infiltrates, less dermal atypia, and Pautrier microabscesses, the diagnosis of HMF requires correlation with clinical features and careful assessment of epidermotropic cells. [ABSTRACT FROM AUTHOR]

Drawing upon feminist standpoint theory and interviews with pioneering women lawyers in Sri Lanka, I argue for a focus on women as a distinct category in 'legal complex theory'. I consider the following questions in making this claim. What were the internal structures of the legal profession that the older generations of women lawyers encountered as they entered the profession and as they took up positions of leadership? In what ways, if at all, was the 'culture(s)' within the profession patriarchal? In what ways, if any, did the entry and advancement of women impact these internal structures of the profession and its culture(s)? And what can we learn from these experiences in predicting the future trajectory of the legal profession? The analytical expansion that I propose reveals gender‐based dynamics within the legal complex, such as gender‐stereotyped perceptions about women lawyers within the profession, the 'feminization' of the profession, and 'gender segmentation' within its different spheres. [ABSTRACT FROM AUTHOR]

Introducing passive devices in the form of inserts helps to increase the heat transfer characteristics in a circular pipe. In the present work, the feasibility of using two twisted tapes has been numerically studied under laminar flow conditions. Two twisted tapes with configurations of co‐swirl and counter‐swirl conditions were simulated for Re ranging from 1000 to 2500. Heat transfer characteristics like Nusselt number, friction factor, and thermohydraulic performance index (THPI) were investigated. Even the effect of spacing of the tubes inside the pipe was numerically studied. Results indicated that the insertion of two tapes will improve the performance of the circular tube compared with a single tape in terms of a higher Nu and higher THPI. It is observed that for the co‐swirl condition for a Reynolds number of 1000, Nu and THPI is 38% and 29% higher than using a single tape, whereas, for the counter‐swirl condition, they are 43% and 34% higher than that of the single tape condition. Also, it is revealed that counter swirl positioning of the tape with an L/D ratio 0.56 outperformed all other configurations with the highest THPI. [ABSTRACT FROM AUTHOR]

In the present study, the effect of a helical coiled tape on the heat transfer characteristics in a tubular heat exchanger has been studied. Numerical analysis is carried out in a tubular heat exchanger with a helical coiled tape insert under laminar flow conditions. The heat transfer characteristics, like Nusselt number (Nu) and friction factor (f), have been determined. Numerical modeling is undertaken and validated using analytical results. To study the parametric variation, simulation is carried out for different width ratios (WR) and twist ratios (TRs). It is observed that Nu increases as the WR is increased and the TR is reduced. The thermohydraulic performance index (THPI) is measured and found to be higher for a combination of a higher WR and a higher TR. From the tested values, it is seen that for a combination of WR = 3 and TR = 1.25, the maximum THPI was observed. It is concluded that both the tape width and pitch will significantly influence the thermohydraulic characteristics in a tubular heat exchanger with a helical tape insert inserted. [ABSTRACT FROM AUTHOR]

The study aimed to determine the prevalence of occult hepatitis B virus infection among HIV-infected persons and to evaluate the use of a pooling strategy to detect occult HBV infection in the setting of HIV infection. Five hundred and two HIV-positive individuals were tested for HBV, occult HBV and hepatitis C and D with serologic and nucleic acid testing (NAT). We also evaluated a pooled NAT strategy for screening occult HBV infection among the HIV-positive individuals. The prevalence of HBV infection among HIV-positive individuals was 32 (6.4%), and occult HBV prevalence was 10%. The pooling HBV NAT had a sensitivity of 66.7% and specificity of 100%, compared to HBV DNA NAT of individual samples. In conclusion, this study found a high prevalence of occult HBV infection among our HIV-infected population. We also demonstrated that pooled HBV NAT is highly specific, moderately sensitive and cost-effective. As conventional HBV viral load assays are expensive in resource-limited settings such as India, pooled HBV DNA NAT might be a good way for detecting occult HBV infection and will reduce HBV-associated complications. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotube (SWNT) electrodes that are chemically and mechanically robust are fabricated using a simple drop cast method with thermal annealing and acid treatment. An electronic-type selective decrease in sheet resistance of SWNT electrodes with HNO3 treatment is shown. Semiconducting SWNTs show a significantly higher affinity toward hole doping in comparison to metallic SWNTs; a ≈12-fold and a ≈fivefold drop in sheet resistance, respectively. The results suggest the insignificance of the electronic type of the SWNTs for the film conductivity after hole doping. The SWNT films have been employed as transparent hole extracting electrodes in bulk heterojunction (BHJ) organic photovoltaics. Performances of the devices enlighten the fact that the electrode film morphology dominates over the electronic type of the doped SWNTs with similar sheet resistance and optical transmission. The power conversion efficiency (PCE) of 4.4% for the best performing device is the best carbon nanotube transparent electrode incorporated large area BHJ solar cell reported to date. This PCE is 90% in terms of PCEs achieved using indium tin oxide (ITO) based reference devices with identical film fabrication parameters indicating the potential of the SWNT electrodes as an ITO replacement toward realization of all carbon solar cells. [ABSTRACT FROM AUTHOR]

The use of biodiesel along with other alternative fuel sources is expected to address the twin problems of pollution and energy security. This study investigates the effect of injection pressure (IP) on the performance, combustion, and emission characteristics of a four-stroke single cylinder direct injection diesel engine fuelled with a biofuel, namely cardanol-methanol-diesel blend (B20M10). The results are compared with baseline diesel operations under standard operating conditions. The biofuel blend B20M10 (20% cardanol, 10% methanol, and 70% diesel) is used as fuel, and the combustion, performance, and emission characteristics are investigated at IP levels of 180, 200, and 220 bar. The test results show that the optimum fuel IP is 220 bar with B20M10. At this optimized pressure, a reduction in CO, HC, and smoke emissions with an increase in the oxides of nitrogen (NOx) and brake thermal efficiency (BTE) are noticed compared with 180 and 200 bar B20M10 operations. When compared with diesel (180 bar IP), B20M10 blend at 220 bar IP gives marginally lower BTE and lower CO and HC emissions, but oxides of nitrogen and smoke are slightly more. © 2014 Curtin University of Technology and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

It is widely considered that charge carrier extraction in bulk‐heterojunction organic photovoltaics (BHJ OPVs) is most efficient when the area of contact between the semiconductor layers and the electrodes is maximized and the electrodes are electrically homogeneous. Herein, it is shown that ≈99% of the electrode surface can in fact be insulating without degrading the efficiency of charge carrier extraction, provided the spacing of the conducting areas is less than or equal to twice the optimal thickness of the BHJ layer. This striking result is demonstrated for BHJ OPVs with both conventional and inverted device architectures using two different types of BHJ OPVs, namely, PCDTBT:PC70BM and the ternary blend PBDB‐T:ITIC‐m:PC70BM. This finding opens the door to the use of a large pallet of materials for optical spacers and charge transport layers, based on a low density of conducting particles embedded in a wide bandgap insulating matrix. [ABSTRACT FROM AUTHOR]

Effectively utilizing agro residues, when abundantly available, can help energy conservation efforts and increase farmers' incomes. This article highlights the effective utilization of agro and industrial biomass residues in the form of briquettes. The various types of feedstock used and the technologies adopted in the briquetting process are discussed. Process parameters and feedstock variables influencing briquetting are described. Combustion studies undertaken using briquettes are comprehensively detailed. This literature review reveals that the combustion characteristics of briquettes not only depend on the type of the feedstock but also on the density, moisture content, binder percentage, and method used for briquetting. Higher ash content lowers the calorific value. The ash formed during combustion causes slagging and fouling which in turn lead to corrosion. It is concluded that biomass briquettes can meet the energy demands for cooking and heating needs, especially in rural areas where abundant biomass feedstock is available. It is recommended that research focuses more on investigating emissions along with the combustion of briquettes manufactured from different origins. [ABSTRACT FROM AUTHOR]

A variety of new pyrazole derivatives bearing multifunctionalized pyrimidine [cf. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, C9H11N3O2, contains two mol-ecules (A and B), which exist in Z conformations with respect to their C=N double bond. The dihedral angles between the benzene ring and the pendant hy-droxy-carbamimidoyl and acetamide groups are 28.58 (7) and 1.30 (5)°, respectively, in mol-ecule A and 25.04 (7) and 27.85 (9)°, respectively, in mol-ecule B. An intra-molecular N-H⋯N hydrogen bond generates an S(6) ring in both mol-ecules. Mol-ecule A also features an intra-molecular C-H⋯O inter-action, which closes an S(6) ring. In the crystal, the mol-ecules are linked by N-H⋯O, N-H⋯N, O-H⋯O, O-H⋯N, C-H⋯O and C-H⋯N hydrogen bonds and C-H⋯π inter-actions, generating a three-dimensional network.

In the cation of the title compound, C(9)H(12)NO(2) (+)·Cl(-), the dihedral angle between the 2-oxoethanaminium N-C-C(=O)- plane [maximum deviation = 0.0148 (12) Å] and the benzene ring is 7.98 (8)°. The meth-oxy group is approximately in-plane with the benzene ring, with a C-O-C-C torsion angle of -2.91 (18)°. In the crystal, the cations and chloride anions are connected by N-H⋯Cl and C-H⋯Cl hydrogen bonds, forming a layer parallel to the bc plane. A C-H⋯π inter-action further links the layers.

In the title compound, C(15)H(9)Cl(2)N(3)O, an intra-molecular C-H⋯O inter-action generates an S(7) ring motif. The cyclo-penta-1,3-diene ring forms dihedral angles of 1.93 (6) and 2.78 (6)° with its attached benzene rings. In the crystal, mol-ecules are linked by C-H⋯N and C-H⋯O hydrogen bonds, thereby forming layers lying parallel to the ac plane. The crystal also features a π-π inter-action with a centroid-centroid distance of 3.5612 (6) Å.

In the title compound, C(10)H(13)NO, the C-C-C-C torsion angle formed between the benzene ring and the butan-2-one oxime unit is 73.7 (2)°, with the latter lying above the plane through the benzene ring. In the crystal, inter-molecular O-H⋯N hydrogen bonds link pairs of mol-ecules into dimers, forming R(2) (2)(6) ring motifs which are stacked along the a axis.

In the title compound, C(15)H(17)N(3)O, the 1H-imidazo[4,5-c]quinoline ring system is approximately planar, with a maximum deviation of 0.036 (1) Å. The C-N-C-C torsion angles formed between this ring system and the isobutyl unit are -99.77 (16) and 79.71 (17)°. In the crystal, inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into chains along the c axis.

In the crystal of the title molecular salt, 2C(6)H(7)FN(+)·SO(4) (2-), the cations and anions are linked by N-H⋯O and C-H⋯O hydrogen bonds into sheets parallel to the ab plane. The crystal studied was found to be a racemic twin with a 0.50 (10):0.50 (10) domain ratio.