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The properties of unidirectional (UD) composites has been investigated by analyzing their elastic and strength characteristics under shear loading. The UD fiber‐reinforced polymer (FRP) composites usually consist of fibers randomly dispersed throughout the cross‐section in the transverse direction which is generally not accounted for. A micromechanical model based on finite element analysis (FEA) approach is utilized here to examine these properties. The study begins by identifying micro scale unit cells or repetitive unit cells (RUCs) at the micro scale, as well as representative volume elements (RVEs). The distribution of fiber volume fraction (Vf) varies among various micro scale unit cells positioned in the transverse cross‐section. The elastic properties and strength are estimated by considering the properties of the matrix and fibers, and the configuration of micro scale unit cells, which feature a fiber arrangement which is categorized as hexagonal and varying Vf at different locations (from 0.35 to 0.75). However, the overall Vf for the UD composite remains constant at 0.65. Studies are also carried out with the random distribution of fibers at micro scale unit cells. The findings reveal that the random distribution of fibers significantly impacts the shear behavior of the composite. This investigation provides valuable insights into how the mechanical properties of the UD composite are subjective by the distribution of fiber, thereby contributing to the design and development of this light weight high‐performance material. Highlights: Elastic and strength analysis of UD composites is presented.Emphasis is on fiber dispersion in transverse plane.Microscale unit cells, RUCs and RVE are identified.Studies are carried out based on micromechanical model.Influence of fiber distribution on shear behavior is investigated. [ABSTRACT FROM AUTHOR]

Summary: With the increase in the penetration level of renewables into the grid, the virtual synchronous generator (VSG) concept has emerged as an attractive solution for controlling grid‐tied inverters. The variation in reactive power also affects the real power of the system as well. To address the voltage variations and phase angle variations occurring because of the energy storage elements, the control of the reactive power loop (RPL) is important. Also, it is used to maintain voltage regulation and improve the power factor of the VSG system. This paper focuses on the damping of oscillations occurring because of load variation by proper adjustment of the rotational inertia, damping coefficient, droop coefficient, and regulatory coefficient of reactive power with a proposed adaptive control strategy. Small‐signal analysis of the active and reactive power and point of common coupling (PCC) have been derived, and the detailed dynamic performances are analyzed. The influences of parameters perturbation on PCC voltage and reactive power were investigated. Furthermore, adaptive control includes optimizing dynamic indexes such as rise time, delay time, and response settling time. Finally, the performance and improvement in the results of VSG with and without adaptive control are compared. [ABSTRACT FROM AUTHOR]

Summary: This article presents an improved least mean square (LMS) algorithm‐based control approach for a three‐phase grid interfaced solar photovoltaic (GISPV) system for smart building applications. The SPV is primarily utilized to supply household loads, and the absence or intermittency of SPV is curbed by utilizing power from the grid. The majority of household loads are nonlinear loads that affect the grid power quality (PQ). However, the effects of both linear and nonlinear loads on grid PQ have been analyzed in this article. This article proposes a Gaussian Kernel function‐based normalized LMS (GKNLMS) algorithm to calculate the active peak weight component of the load current, thereby utilizing it to obtain a sinusoidal reference current. Considering a higher step size and utilizing the Gaussian Kernel function for reduced mean square error (MSE) improves both the convergence rate and accuracy of estimation in the conventional LMS. The proposed control technique effectively addresses system anomalies caused by dynamic solar irradiance, load variation, and unbalanced loading conditions. Furthermore, the system response with the GKNLMS algorithm is assessed in MATLAB/Simulink and validated by developing a laboratory setup of the system for experimentation. [ABSTRACT FROM AUTHOR]

Summary: This paper develops a variable step size robust normalized least mean absolute third (VSSRNLMAT)‐based control scheme for a three‐phase grid‐tied multifunctional photovoltaic system (GTMPVS). The GTMPVS delivers PV power to grid‐connected loads and feeds excess power to the grid through a voltage source converter (VSC) when PV power is available. It enhances power quality (PQ) by mitigating current harmonics and compensating for an unbalanced load and reactive power simultaneously. The proposed control scheme accurately extracts the fundamental active and reactive weight components of nonlinear load current. The power exchange at the grid side occurs with balanced and sinusoidal grid currents. During the absence of PV power, the VSC continues its operation as a distribution static compensator (DSTATCOM), thus increasing the effective utilization of the power electronic switches employed in the VSC. The GTMPVS model is created in MATLAB/Simulink. The response of GTMPVS is observed under steady‐state and dynamic operating conditions while feeding power to a nonlinear load. The dynamic operating conditions are created by a change in solar irradiation and an unbalanced nonlinear load. Further, the proposed VSSRNLMAT control scheme is compared with some of the other adaptive filtering‐based control schemes, including least mean square (LMS), least mean fourth (LMF), least mean absolute third (LMAT), and normalized LMAT (NLMAT) in terms of convergence, oscillations, mean square deviation (MSD), computational complexity, and grid current total harmonic distortion (THD). It is found that the VSSRNLMAT control scheme offers THD of grid current as per IEEE‐519 standard. The proposed control scheme is implemented to operate the laboratory‐developed GTMPVS to verify the simulation results. [ABSTRACT FROM AUTHOR]

This article presents an isolated bidirectional DC‐DC dual active bridge (DAB) converter with an integral sliding mode‐based direct power control (SM‐DPC). Maintaining the dc‐link stability and obtaining a robust control for the converter during sudden load change is a significant challenge. The sliding mode control is well known for its robustness, stability, and tracking performance. The sliding surface based on output voltage error is selected, while the proposed method utilizes the equivalent control approach to generate the power reference for the DAB converter. The direct power control provides an easy control method for the DAB converter as the output voltage depends on the transmitted power, governed by the phase shift angle of two H‐bridges of the converter. The proposed method enhances the steady‐state performance and renders a fast transient response under load change and input voltage variation. Moreover, the method avoids complicated converter modeling and utilizes the voltage dynamic equation and power transfer equation for the controller design. The controller performance and effectiveness are validated with experimental results for a 2‐kW DAB converter. [ABSTRACT FROM AUTHOR]

An attempt has been made to assess the dipeptidyl peptidase‐IV (DPP‐IV) inhibitory potential of α‐lactalbumin separated from milk of Gir cow. α‐lactalbumin hydrolysates were prepared using three different enzymes at different enzyme‐to‐substrate (E:S) ratios (1:25, 1:50 and 1:100) treated for 2‐ to 12‐h durations. Pepsin‐treated hydrolysates showed maximum DPP‐IV inhibition of 87.81 ± 0.84% (IC50 = 0.78 mg/mL). The permeate of 3 kDa, which exhibited 84.47 ± 2.29% DPP‐IV inhibition, was fractionated through RP‐HPLC. All fractions were analysed for DPP‐IV inhibition activity. One novel peptide was identified through LC‐MS/MS, which showed adequate DPP‐IV inhibition (IC50 = 4.93 mM). [ABSTRACT FROM AUTHOR]

Experimental studies are presented on the shear plugging and frictional behaviour of composites and fabrics under quasi-static loading. The primary focus is on the effect of specimen thickness on quasi-static shear plugging behaviour. In the present study, quasi-static shear plugging and through-the-thickness frictional tests are carried out on three types of materials. The materials investigated are 2D plain weave E-glass/epoxy, 2D plain weave T300 carbon/epoxy and 2D plain weave E-glass fabric. Typical results on shear plugging strength and frictional behaviour are presented. Effect of specimen thickness on quasi-static shear plugging behaviour is also investigated. [ABSTRACT FROM AUTHOR]

Acrylic is being used in structural applications because of its higher resistance to projectile impacts. High strain rate shear loading is one of the critical conditions. In the present study, properties of typical acrylic under high strain rate shear loading are presented. Torsional Split Hopkinson Bar apparatus was used for the studies in the shear strain rate range of 290 per sec to 791 per sec. Thin-walled tubular specimens with hexagonal flanges were used for the experimental studies. Details of specimen configuration, data acquisition, and processing are presented. Shear strength is presented as a function of shear strain rate. It is observed that the shear strength at high strain rate is enhanced up to 25% compared with that at quasi-static loading in the range of parameters considered. Comparison of torque versus time behavior derived from signals obtained from strain gauges mounted on incident bar and transmitter bar is also presented. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

Traumatized anterior teeth need quick, aesthetic and functional repair. Along with aesthetics, the physical properties of restorative material should also be considered for long-lasting restoration. Fibre reinforcement has been tried as a newer technique to improve the physical properties of composite materials. Hence, this study was carried out to evaluate the fracture resistance of microhybrid composite, nano composite and fibre-reinforced composite used for restoration of incisal edge of fractured maxillary central incisors. Extracted permanent maxillary central incisors were randomly divided into four groups of 10 samples each: control group with intact teeth (Group A), microhybrid composite (Esthet X; Dentsply/Caulk, Milford, DE, USA) (group B), nano composite (Ceram X; Dentsply/Caulk) (group C) and microhybrid composite reinforced with polyethylene fibre - flowable composite unit [(Ribbond THM; Ribbond Inc., Seattle, WA, USA; Esthet X flow; Dentsply/Caulk)] (group D). The fracture resistance was measured under universal testing machine at a speed of 1 mm min with the loading tip of 2 mm diameter. The samples were further evaluated for mode of fracture under stereomicroscope at 3.5× magnification. The data were analysed using one-way and Tukey's test for fracture resistance. Group A and group D exhibited significantly higher fracture resistance than group B and group C. No significant difference was found between group B and group C as well as between group A and group D. Fisher's exact test for the mode of fracture revealed no statistical significance. It was concluded that fibre reinforcement of composite could be an alternative technique for restoration of fractured anterior teeth for better aesthetics and longevity of the restoration. [ABSTRACT FROM AUTHOR]

In tropical and subtropical regions of the world, leishmaniasis is endemic and causes a range of clinical symptoms in people, from severe tegumentary forms (such as cutaneous, mucocutaneous, and diffuse leishmaniasis) to lethal visceral forms. The protozoan parasite of the genus Leishmania causes leishmaniasis, which is still a significant public health issue, according to the World Health Organization 2022. The public's worry about the neglected tropical disease is growing as new foci of the illness arise, which are exacerbated by alterations in behavior, changes in the environment, and an enlarged range of sand fly vectors. Leishmania research has advanced significantly during the past three decades in a few different avenues. Despite several studies on Leishmania, many issues, such as illness control, parasite resistance, parasite clearance, etc., remain unresolved. The key virulence variables that play a role in the pathogenicity-host-pathogen relationship of the parasite are comprehensively discussed in this paper. The important Leishmania virulence factors, such as Kinetoplastid Membrane Protein-11 (KMP-11), Leishmanolysin (GP63), Proteophosphoglycan (PPG), Lipophosphoglycan (LPG), Glycosylinositol Phospholipids (GIPL), and others, have an impact on the pathophysiology of the disease and enable the parasite to spread the infection. Leishmania infection may arise from virulence factors; they are treatable with medications or vaccinations more promptly and might greatly shorten the duration of treatment. Additionally, our research sought to present a modeled structure of a few putative virulence factors that might aid in the development of new chemotherapeutic approaches for the treatment of leishmaniasis. The predicted virulence protein's structure is utilized to design novel drugs, therapeutic targets, and immunizations for considerable advantage from a higher understanding of the host immune response., (© 2023 John Wiley & Sons Ltd.)

In the title compound, C(11)H(12)O(2), the six-membered ketone ring fused to the 7-meth-oxy benzene ring adopts a slightly distorted envelope configuration with the central methyl-ene C atom being the flap. The crystal packing is stabilized by weak inter-molecular C-H⋯O and C-H⋯π inter-actions, which lead to supra-molecular layers in the bc plane.

In the crystal structure of the title compound, C(22)H(21)Cl(2)NO(2), the piperidinone ring is in a boat conformation.

Binding of chemoattractant to polymorphonuclear leukocytes (PMNL) triggers a series of events like polymerization of actin and tubulin, orientation of cells, chemotaxis, increase in fluid pinocytosis and phagocytosis, and stimulation of microbicidal pathways which includes lysosomal degranulation and generation of reactive oxygen species. Earlier studies from our laboratory have shown that stimulation of chemotaxis, fluid pinocytosis, and actin polymerization of CML PMNL in response to a synthetic chemotactic peptide formyl-methionyl-leucyl-phenylalanine (fMLP) is significantly lower than that in normal PMNL. It is not known whether this lower response of CML PMNL to fMLP is a global phenomenon involving different chemoattractant receptors or is restricted to the fMLP pathway. We have evaluated chemoattractant induced degranulation process in normal and CML PMNL to fMLP, platelet activating factor (PAF), leukotriene B4 (LTB4), and an analogue of fMLP viz formyl-methionine-1 aminocyclooctane 1 carboxylic acid-phenylalanine-O-methionine (FACC8) using release of lysozyme as a parameter. We find that after stimulation with fMLP and FACC8, the mean percent release of lysozyme was significantly lower in CML PMNL as compared to that in normal cells (P < 0.001). There was no significant difference between the two after stimulation with PAF and LTB4. The results indicate that the fMLP pathway is suppressed in CML granulocytes whereas PAF and LTB4 pathways appear unaltered in these cells. We therefore also studied the kinetics of peptide-receptor interaction with a labelled hexapeptide fNLPNTL which binds to the fMLP receptor. Our results show that the number of fMLP receptors/cell is significantly lower in CML PMNL (P < 0.05) than in normal PMNL, while their affinity constants and dissociation constants were comparable.