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Efficiency of photovoltaic (PV) systems is decreased by mismatch losses resulting from uneven panel irradiation. Current compensation techniques that inject compensatory current and measure currents by periodic row short-circuiting are unavoidably blackout-causing. In this work, a novel current compensation technique is presented that dynamically measures and reacts to variations in irradiance using light sensors on each panel. The program compiles these data to determine the overall irradiance of each row and to precisely modify the injected current to sustain output without any interruptions to operation. The proposed approach lowers mismatch losses more effectively than traditional techniques, as demonstrated by MATLAB/Simulink simulations of seven shading patterns. Under center shading, the proposed approach raised system efficiency by 36%. These results indicate a move towards more flexible solar energy solutions by implying that sensor-driven data analytics can increase PV system operational efficiency and reliability.

The low-cost magnet less switched reluctance motor (SRM) speed-torque characteristics are perfectly suited for electric vehicles (EVs) drive performances are better than polyphase machines. The main drawback of SRM for EVs is torque ripple, it can be mitigated by optimal design aspects. In this study, to design SRM by changing the position of the stator and rotor pole, an increasing number of poles are investigated with optimum geometry. This paper presents the design procedure for EV applications of 250 kg mass, developed power of 2.9 kW and acceleration of 30 kmph. SRM rotor modification with two different cases of design of SRM with exterior rotor case with three-phase stator configuration 8/6, 10/6 and design of SRM with an interior rotor with three and four phases stator configuration 6/4, 8/6. The simulation was carried out using an electromagnet infolytica simulation package. The conditions of flux linkages, static torque, and rotor configurations are obtained using finite elements. FEA is used to verify the design of the SRM from an electrical standpoint. The results and performance analysis of the SRM drive were compared and analyzed for both cases. It is observed during the static and transient analysis that, the torque ripple in the 8/6 interior rotor design is lesser than in the exterior rotor design. The Interior rotor configuration 8/6 model may best be suited for EV’s high-speed application due to its low torque ripple characteristics compared to other models.

The magnet-less switched reluctance motor (SRM) speed-torque characteristics are ideally suited for traction motor drive characteristics and its advantage to minimize the overall cost of on-road EVs. The main drawbacks are torque and flux ripple, which have produced high in low-speed operation. However, the emerging direct torque control (DTC) operated magnitude flux and torque estimation with voltage vectors (VVs) gives high torque ripples due to the selection of effective switching states and sector partition accuracy. On the other hand, the existing model predictive control (MPC) with multiple objective and optimization weighting factors produces high torque ripples due to the system dynamics and constraints. Therefore, existing DTC and MPC can result in high torque ripples. This paper proposed a finite set (FS)-MPC with a single cost function objective without weighting factor: the predicted torque considered to evaluate VVs to minimize the ripples further. The selected optimal VV minimizes the SRM drive torque and flux ripples in steady and dynamic state behaviour. The classical DTC and proposed model were developed, and simulation results were verified using MATLAB/Simulink. The proposed model operated in SRM drives experimental results to prove the effective minimization of torque and flux ripples compared to the existing DTC. [ABSTRACT FROM AUTHOR]

Summary: The switched reluctance motor (SRM) is a prominent electrical machine drive with low cost and good performance in different drive applications. This machine's main drawbacks are torque ripple and flux ripple. However, the existing SRM‐operated direct torque control (DTC) Voltage vectors (VVs) give high torque ripples due to improper sector division and minimum selection of VVs switching states. On the other hand, a two‐level hysteresis torque band can result in torque ripples. Therefore, this paper proposed DTC using 16 partitions, active small and large VVs, and a multilevel hysteresis torque band (MHTB) strategy to mitigate the torque ripple further. More active VVs (i.e., 16) are employed in the modified sector‐based switching tables, suppressing the torque ripples. The proposed strategy is verified and validated using MATLAB/Simulink. The detailed result discusses the response of torque, flux, and speed of SRM. The DTC‐operated SRM drive experimental results prove the effective minimization of torque ripples in the proposed DTC compared to the existing DTC. [ABSTRACT FROM AUTHOR]

Background: Andrographis paniculata (Burm.f.) Nees has been well-researched for its immunomodulatory effects. Objective(s): To investigate the immunomodulatory effects of standardized A. paniculata extract (SAPE) in healthy adults. Materials and methods: The study was an open-label, single-centre study conducted for 30 days. Thirty participants with absolute lymphocyte counts of 1000–4000 cells/mm3 were enrolled and were instructed to ingest 200 mg of SAPE daily for 30 days. The participants visited the clinic at baseline, and days 3, 7, and 30. Immune cells such as NK cell (CD3-CD16+CD56+), T cells (CD3+), T helper cells (CD3+CD4+), T cytotoxic cells (CD3+CD8+) were measured using flow cytometry. Serum cytokines that include interferon gamma (IFN-γ), interleukin-4 (IL-4), interleukin-2 (IL-2), interleukin-12 (IL-12), and tumor necrosis factor alpha (TNF-α) were measured using ELISA. The SAPE used in this study was a standardized proprietary extract (AP-Bio®/KalmCold®) developed from the leaf extracts of A. paniculata. Results: SAPE increased T cells, T helper cells and significantly increased IFN-γ, IL-4, and decreased IL-2 at day 30. A subgroup analysis of participants with absolute lymphocyte counts of 1000–3000 cells/mm3 indicated that there is a significant increase in the T cells, T helper cells at day 7 and 30 and significant increase in IFN-γ, IL-4 and decrease in IL-2 at day 30. There was no treatment related adverse effects following SAPE intake for 30 days. Conclusion: Supplementation of SAPE resulted in immunomodulatory effects evidenced by its effects on immune cells and cytokines and it was found to be safe and tolerable.

Introduction: In India, the prevalence of gallstones is considered as a major public health problem and among diabetic patients the prevalence is still more increasing. Presence of Diabetic Autonomic Neuropathy (DAN) is a triggering factor for gallbladder diseases among diabetic patients. Aim: To compare the gallbladder volume and contraction index between diabetic patients and non diabetic healthy controls. Materials and Methods: A cross-sectional study was conducted in a tertiary care hospital at Chennai for a period of six months from June 2019 to December 2019. The total 90 subjects were divided into two groups of 45 each, group A consist of 45 known Type I or Type II diabetes mellitus (DM)and group B with 45 non diabetic healthy controls. The gallbladder volume was assessed initially in the fasting state, then the patient was asked to have fatty meal and again the gallbladder volume was measured after two hours for all the patients and the gallbladder contraction index was calculated using these values. Autonomic neuropathy grading was done after performing neuropathy assessment tests and the association between the gallbladder contraction index and grading of autonomic neuropathy was analysed. Results: The mean fasting and postprandial gallbladder volume were much higher among diabetic patients compared to non diabetic controls and similarly the gallbladder contraction index was lesser among diabetic patients compared to the controls (16.6±5.9 cm3 , 4.03±1.8 cm3 ) and (32.08±11.7 cm3 , 17.4±10.6 cm3 ) the difference was found to be statistically significant (p-value

Plectranthus amboinicus (Lour.) Spreng. has been used for the treatment of many diseases in traditional Indian systems of medicine. In the present study, Polyphenolic profiling was carried out in leaves of P. amboinicus using spectrophotometric and mass spectroscopic analyses. The total Polyphenolics of different extracts such as ethanol, acetone and n-butanol were estimated spectrophotometrically and major phenolic compounds of ethanol extract was characterized by HPLC coupled tandem mass spectroscopic analysis. Keywords: Plectranthus amboinicus, Phenolics, LC/MS

Cleft lip and palate (CLP) is the most common congenital craniofacial anomaly. Rehabilitation of CLP generally requires a team approach. Alveolar and nasal reconstruction for these patients is a challenge for the reconstructive surgeon. Various procedures have been attempted to reduce the cleft gap, so as to obtain esthetic results postsurgically. The presurgical nasoalveolar molding (PNAM) technique, developed by Grayson, is a new approach to presurgical infant orthopedics. PNAM reduces the severity of the initial cleft alveolar and nasal deformity. Thus, it enables the surgeon and the patient to enjoy the benefits associated with repair of a cleft deformity that is minimal in severity. This article presents a brief insight into PNAM with a case series of three different cases (one unilateral and two bilateral) which underwent PNAM treatment and gave an excellent surgical prognosis.

Context: The survival of atraumatic restorative treatment (ART) restorations would probably increase if near total elimination of cariogenic microorganisms could be done in the process of cavity cleaning before going ahead with the restoration. Thus, use of naturally occurring disinfecting agents for achieving this goal could herald a new beginning in the field of contemporary minimum intervention dentistry. Aims: To evaluate the efficacy of hand instruments in excavating dental caries and comparatively evaluate the roles of Aloe vera and propolis as potential cavity disinfecting agents after minimally invasive hand excavation of dental caries. Settings and Designs: Experimental, in vivo intergroup split mouth, randomized clinical trial. Subjects and Methods: The study included Group I (Control), Group II (A. vera) and Group III (propolis). Ten patients with three teeth each have occlusal/occlusoproximal lesions suitable for ART were selected. Dentinal samples were collected three times from each tooth viz., preexcavation, postexcavation and postdisinfection of the cavities. These dentinal samples were subjected to microbiological analyses for total viable count. Statistical Analysis Used: Repeated measures of analysis of variance (ANOVA) with Bonferroni post-hoc test and one-way ANOVA with Tukey post-hoc test. Results: In all the three groups, significant amount of bacteria were left behind after hand excavation. Group II and Group III, in which cavities were treated with A. vera and propolis extracts respectively, showed a significant reduction in the bacterial counts when compared to control the group. Conclusions: Hand excavation alone does not completely eliminate bacteria, which may predispose treated teeth to secondary caries. Both propolis and A. vera extracts can be used as potential natural disinfecting agents, thereby embracing the concept of phytotherapy in minimum intervention dentistry.