Performance optimization of interleaved boost converter with ANN supported adaptable stepped-scaled P&O based MPPT for solar powered applications.

Solar energy is the most promising among many renewable energy sources to meet the increasing demand. Photovoltaic (PV) based power generating solutions are expected to gain popularity as a power source for different applications, including independent and grid connected loads, due to their cleanliness, high performance, and high dependability. The efficacy of photovoltaic systems is impacted by several elements, including geographical location, positioning, shadowing effects, and local climate conditions. In order to fulfil the demands of loads, an interleaved boost converter is utilized, which has a reduced number of filters with less stress on the devices. Solar powered systems employ several maximum power point tracking (MPPT) methodologies. However, when there is partial shading, many power peaks arise, which complicates the identification of the overall peak. Although MPPT approaches are designed to measure and maintain the global maximum power point (GMPP), there are still significant oscillations observed around the GMPP with subpar settling time, tracking efficiency, and conversion efficiency. In this work, novel hybrid MPPT technique called artificial neural network supported adaptable stepped-scaled perturb and observe (ANN-ASSPO) method and water cycle optimization based perturb and observe (WCO-PO) have been proposed. Artificial neural network (ANN) has been used to determine the best scaling factor in ANN-ASSPO MPPT. Performance is enhanced in ANN-ASSPO MPPT by using the optimum scaling factor, particularly in situations when the irradiance is rapidly changing/partial shading conditions. Similarly, in WCO-PO MPPT water cycle optimization is used to determine the peak power when the PV panel is subjected to partial shading conditions. The performances of proposed hybrid MPPT ANN-ASSPO and WCO-PO techniques have been compared in terms of power generated, output voltage, average settling time and conversion efficiency. The MATLAB/Simulink tool is employed to carry out the experiment for this study.

Extent of knowledge and attitudes on plagiarism among undergraduate medical students in South India - a multicentre, cross-sectional study to determine the need for incorporating research ethics in medical undergraduate curriculum.

BACKGROUND: Undergraduate medical students in India participate in various research activities However, plagiarism is rampant, and we hypothesize that it is the lack of knowledge on how to avoid plagiarism. This study's objective was to measure the extent of knowledge and attitudes towards plagiarism among undergraduate medical students in India. METHODS: It was a multicentre, cross-sectional study conducted over a two-year period (January 2018 - December 2019). Undergraduate medical students were given a pre-tested semi-structured questionnaire which contained: (a) Demographic details; (b) A quiz developed by Indiana University, USA to assess knowledge; and (c) Attitudes towards Plagiarism (ATP) questionnaire. RESULTS: Eleven medical colleges (n = 4 government medical colleges [GMCs] and n = 7 private medical colleges [PMCs]) participated. A total of N = 4183 students consented. The mean (SD) knowledge score was 4.54 (1.78) out of 10. The factors (adjusted odds ratio [aOR]; 95% Confidence interval [CI]; p value) that emerged as significant predictors of poor knowledge score were early years of medical education (0.110; 0.063, 0.156; < 0.001) and being enrolled in a GMC (0.348; 0.233, 0.463; < 0.001).The overall mean (SD) scores of the three attitude components namely permissive, critical and submissive norms were 37.56 (5.25), 20.35 (4.20) and 31.20 (4.28) respectively, corresponding to the moderate category. CONCLUSION: The overall knowledge score was poor. A vast majority of study participants fell in the moderate category of attitude score. These findings warrant the need for incorporating formal training in the medical education curriculum.

A Rare Case of Bilateral Popliteal Artery Occlusion.

Peripheral arterial disease (PAD) is a common condition of the upper and lower extremities caused by atherosclerosis. It is often accompanied by symptomatic cardiovascular and cerebrovascular disease and is a major risk factor for amputation of an extremity. Timely diagnosis and intervention can prevent morbidity in these patients. We describe a case of a 48-year-old man with multiple co-morbidities who presented to our emergency department (ED) complaining of acute onset of bilateral leg pain. He was found to have bilateral acute popliteal artery occlusion confirmed by angiography of the lower limbs. Treatment was started early, right after reaching the provisional diagnosis. Popliteal artery occlusion is quite common, but it becomes a rare diagnosis when it happens bilaterally. Detailed evaluation of the peripheral arterial circulation and an early diagnosis seem to be important in the ED management of these patients.

Impact of Adaptive Radiotherapy on Locally Advanced Head and Neck Cancer - A Dosimetric and Volumetric Study.

UNLABELLED: Objective of the study is to evaluate volumetric and dosimetric alterations taking place during radiotherapy for locally advanced head and neck cancer (LAHNC) and to assess benefit of replanning in them. MATERIALS AND METHODS: Thirty patients with LAHNC fulfilling the inclusion and exclusion criteria were enrolled in a prospective study. Planning scans were acquired both pre-treatment and after 20 fractions (mid-course) of radiotherapy. Single plan (OPLAN) based on initial CT scan was generated and executed for entire treatment course. Beam configuration of OPLAN was applied to anatomy of interim scan and a hybrid plan (HPLAN30) was generated. Adaptive replanning (RPLAN30) for remaining fractions was done and dose distribution with and without replanning compared for remaining fractions. RESULTS: Substantial shrinkage of target volume (TV) and parotids after 4 weeks of radiotherapy was reported (p<0.05). No significant difference between planned and delivered doses was seen for remaining fractions. Hybrid plans showed increase in delivered dose to spinal cord and parotids for remaining fractions. Interim replanning improved homogeneity of treatment plan and significantly reduced doses to cord (Dmax, D2% and D1%) and ipsilateral parotid (D33%, D50% and D66%) (p<0.05). CONCLUSIONS: Use of one or two mid-treatment CT scans and replanning provides greater normal tissue sparing alongwith improved TV coverage.

Functional outcome of Schatzker type V and VI tibial plateau fractures treated with dual plates.

BACKGROUND: Dual plate fixation in comminuted bicondylar tibial plateau fractures remains controversial. Open reduction and internal fixation, specifically through compromised soft tissues, has historically been associated with major wound complications. Alternate methods of treatment have been described, each with its own merits and demerits. We performed a retrospective study to evaluate the functional outcome of lateral and medial plate fixation of Schatzker type V and VI fractures through an anterolateral approach, and a medial minimally invasive approach or a posteromedial approach. MATERIALS AND METHODS: We treated 46 tibial plateau fractures Schatzker type V and VI with lateral and medial plates through an anterolateral approach and a medial minimal invasive approach over an 8 years period. Six patients were lost to followup. Radiographs in two planes were taken in all cases. Immediate postoperative radiographs were assessed for quality of reduction and fixation. The functional outcome was evaluated according to the Oxford Knee Score criteria on followup. RESULTS: Forty patients (33 men and 7 women) who completed the followup were included in the study. There were 20 Schatzker type V fractures and 20 Schatzker type VI fractures. The mean duration of followup was 4 years (range 1-8 years). All patients had a satisfactory articular reduction defined as ≤2 mm step-off or gap as assessed on followup. All patients had a good coronal and sagittal plane alignment, and articular width as assessed on supine X-rays of the knee in the anteroposterior (AP) and lateral views. The functional outcome, as assessed by the Oxford Knee Score, was excellent in 30 patients and good in 10 patients. All patients returned to their pre-injury level of activity and employment. There were no instances of deep infection. CONCLUSIONS: Dual plate fixation of severe bicondylar tibial plateau fractures is an excellent treatment option as it provides rigid fixation and allows early knee mobilization. Careful soft tissue handling and employing minimal invasive techniques minimizes soft tissue complications.

Synergistic Effect of Mercury and Chromium on the Histology and Physiology of Fish, Tilapia Mossambica (Peters, 1852) and Lates calcarifer Calcarifer (Bloch, 1790).

Fingerlings of estuarine fishes, Tilapia mossambica and Lates calcarifer were exposed to sub-lethal concentration of mercury and chromium (2.8 ppm) for a period of 28 days. When these fish were exposed to metals concentration, severe gills alterations were observed. But the alteration was less in fish T. mossambica when compared to that of L. calcarife. The fish L. calcarifer exposed to mercury plus chromium, showed lifting up of the epithelium, swelling, hyperplasia, hypertrophy, proliferation of chloride cells, but in mercury treatment, lamellar fusions, fused secondary lamella and necrosis were observed, whereas in T. mossambica the gills disintegration of epithelial cells, desquamated epithelium, hemorrhaged and exhibited complete damage of epithelial cells of lamellae. The Na(+), K(+)-ATPase activity of both gills and plasma showed significant reduction throughout the experiment period in both fishes. The enzyme activity was more drastic in the case of plasma. The results are discussed in relation to the significance of the above enzyme as non-specific biomarkers against environmental stress.

Softeners for hardness removal.

The depletion of water resources, both surface and subsurface and deterioration of water quality made researchers and policy makers to think of the possible remedies to make water sources potable / wholesome. There is a need to address the problems of hardness and fluoride in subsurface water on priority basis. In this direction, bench scale studies were conducted to evaluate the performance of water softeners. Indepth studies were carried out at University B.D.T College of Engineering, Davangere, Karnataka, to assess the performance of bench scale softeners of D to H ratio 1:2, 1:3, 1:4 in removing hardness of varied concentrations from both synthetic and natural water samples. Studies revealed that irrespective of D to H ratio of softeners, the waters having hardness concentration up to 1000 mg/l can be treated to the same degree (81.68% and above). The findings of regeneration studies and cost economics are also summarized in this paper.