Implementation of SHE-PWM technique for single-phase inverter based on Arduino

This paper presents design and practical implementation of single-phase inverter based on selective harmonic elimination-pulse width modulation (SHE-PWM) technique. Microcontroller mega type Arduino used as a controller for producing the gate pulses. The optimized switching angles determination results in wide range of output voltage. Depending on number of switching angles, the lower order harmonics (LOHs) can be eliminated to improve the output voltage waveform. A comparison study using MATLAB/Simulink for sinusoidal-PWM and SHE-PWM techniques, which shows for the same LOH in the output voltage waveform, the SHE-PWM has less number of pulses per half cycle than sinusoidal-PWM strategy. The reduction in number of pulses results less switching losses. The simulation done using ten switching angles to drive R-L load. A prototype of SHE-PWM inverter with R-L load is used to validate the simulation results

A new class of smart gadolinium contrast agent for tissue pH probing using magnetic resonance imaging

Detecting tissue pH in vivo is extremely vital for medical diagnosis and formulation of treatment decisions. To this end, many investigations have been carried out to develop an accurate and efficient method of in vivo pH measurement. Most of the techniques developed so far suffer from inadequate accuracy, due to poor sensitivity at low concentration of the target or nonspecific interactions within the tissue matrix. To overcome these issues, we describe herein the development of a simple, yet reliable, way to estimate pH with high precision using a Gd(III)-DOTA-silyl-based acid-labile group as a pH-sensitive contrast agent with Magnetic Resonance Imaging (MRI). With this method, a change in T1 weighted image intensity of the newly developed pH-sensitive contrast is directly linked to the proton concentration in the media. As a result, we were able estimate the pH of the target with 95% reliability

A randomised double-blind placebo-controlled trial of minocycline and/or Omega-3 fatty acids added to treatment as usual for At Risk Mental States (NAYAB): study protocol

Background The At Risk Mental State (ARMS) describes individuals at high risk of developing schizophrenia or psychosis. The use of antipsychotics in this population is not supported because most individuals with ARMS are unlikely to develop psychosis. Anti-inflammatory treatments and polyunsaturated fatty acids (PUFAs) may have some beneficial effects in the treatment of ARMS. There have been no controlled clinical trials that have investigated the use of minocycline for ARMS and no trials involving PUFAs in combination with other proposed treatments. There is a need to find effective, tolerable and inexpensive interventions for ARMS that are available both in high, low and middle-income countries. Methods A six-month intervention study of minocycline and/or Omega-3 fatty acids added to treatment as usual (TAU) in patients with ARMS will be conducted in Pakistan using a randomised, placebo-controlled, double-blind factorial design. 320 consenting patients with capacity will be recruited from community, general practitioner clinics and psychiatric units. Allowing for a 25% dropout rate, we will recruit 59 completing participants to each study arm, and 236 will complete in total. We will determine whether the addition of minocycline and/or Omega-3 fatty acids to TAU attenuates rate of transition from ARMS to first-episode psychosis and improves symptoms and/or level of functioning in ARMS. We will also investigate whether any candidate risk factors such as negative symptoms, influence treatment response in the ARMS group. The primary efficacy end-point is conversion to psychotic disorder at 12 months post study entry. Analysis will be by intention-to-treat, using analysis-of variance, chi-squared tests and adjusted odds ratios to assess between-group differences. Cox regression analyses will be used to analyse potential between-group differences in time-to-onset of psychosis. Discussion The outcomes of this trial will provide evidence of the potential benefits of minocycline and PUFAs in the treatment of ARMS. Both minocycline and PUFAs are inexpensive are readily available in low/middle-income countries such as Pakistan, and if evidenced, may prove to be safe and effective for treating ARMS

Prognostic Significance of Vascular Endothelial Growth Factor (VEGF) and Her-2 Protein in the Genesis of Cervical Carcinoma

BACKGROUND: Angiogenesis plays a pivotal role in the progression of tumours through the formation of new blood vessels. Vascular endothelial growth factor (VEGF) is a chief factor responsible for inducing and regulating angiogenesis. Additionally, the human epidermal growth factor receptor family of receptors also plays an important role in the pathogenesis of tumours.AIM: This study aimed to examine the association between VEGF and Her-2 protein expression and its correlation with clinic-pathological characteristics; in particular, prognosis.METHODS: A total of 65 cases of cervical carcinoma and 10 samples of inflammatory lesions were evaluated for VEGF and Her-2 protein expression.RESULTS: Expression of VEGF and Her-2 was detected in 63.07% and 43.07% in cervical carcinoma cases respectively whereas control cases did not show any expression. The difference in the expression pattern of both markers comparing cancer and control cases was statistically significant (p < 0.05). However, no significant difference in the expression pattern of VEGF protein was observed among the different grades and stages of tumours (p > 0.05). Comparing different grades of a tumour, expression of Her-2 was detected in 31.8% of well-differentiated tumours, 36.0 % in moderately differentiated tumours and 66.66 % in poorly differentiated cancers. The expression of Her-2 was increased in high-grade tumours, and the difference of expression level between tumour grades was statistically significant (p < 0.05). The expression level of Her-2 protein was not correlated with the stage of a tumour (p > 0.05).CONCLUSION: The present study supports earlier findings that over-expression / up-regulation of VEGF and Her - 2 is linked with poor prognosis and may play a vital role in the development and progression of cervical cancer

Targeting Cellular Metabolism With CPI-613 Sensitizes Pancreatic Cancer Cells to Radiation Therapy

PURPOSE: Local tumor progression is a cause of significant morbidity and mortality in patients with pancreatic ductal adenocarcinoma (PDAC) with surgically unresectable disease. Novel and effective approaches to accomplish durable local control are urgently needed. We tested whether CPI-613 (devimistat), a first-in-class investigational small molecule inhibitor of mitochondrial metabolism, was capable of altering cancer cell energy metabolism and sensitizing PDAC cells to radiation therapy (RT). METHODS AND MATERIALS: The effect of a combined treatment of RT with CPI-613 on the viability of, clonogenic potential of, and cell death induction in PDAC cells (MiaPaCa-2 and Panc-1) was determined using a trypan blue dye exclusion assay, a colony formation assay, and a 7-amino-actinomycin D assay, respectively. The synergistic effects of CPI-613-RT and chemotherapeutic agents (gemcitabine or 5-fluorouracil) were measured in MiaPaCa-2 cells using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and spheroid formation assay. Changes in energy metabolism were determined by profiling metabolites treated with either RT, CPI-613, or both using liquid chromatography-mass spectrometry. RESULTS: This study demonstrates that a combination of single-fraction RT (2 and 10 Gy) with CPI-613 significantly inhibits PDAC cell growth compared with RT alone. Molecular analysis revealed inhibition of α-ketoglutarate dehydrogenase at the protein level. In addition, we demonstrate enhanced cell death of PDAC cells when treated with RT-CPI-613 combination. Targeted metabolomic analysis on PDAC cells post-CPI-613-RT treatment revealed alterations in key mitochondrial metabolites, with broader target engagement by the combination treatment, indicating the sensitization of CPI-613-treated PDAC cells to RT. Furthermore, a combination treatment of CPI-613 with either gemcitabine or 5-fluorouracil in the presence of 2 Gy RT synergistically inhibits PDAC cell proliferation. CONCLUSIONS: Our results support a novel combination of CPI-613-RT that warrants further preclinical and early-phase clinical investigations. A phase 1 trial designed to identify the maximum tolerated dose of CPI-613 in combination with chemo-RT in patients with PDAC was recently initiated (NCT05325281)

Power conversion techniques using multi-phase transformer: Configurations, applications, issues and recommendations

Recently, the superiority of multi-phase systems in comparison to three-phase energy systems has been demonstrated with regards to power generation, transmission, distribution, and utilization in particular. Generally, two techniques, specifically semiconductor converter and special transformers (static and passive transformation) have been commonly employed for power generation by utilizing multi-phase systems from the available three-phase power system. The generation of multi-phase power at a fixed frequency by utilizing the static transformation method presents certain advantages compared to semiconductor converters such as reliability, cost-effectiveness, efficiency, and lower total harmonics distortion (THD). Multi-phase transformers are essential to evaluate the parameters of a multi-phase motor, as they require a multi-phase signal that is pure sine wave in nature. However, multi-phase transformers are not suitable for variable frequency applications. Moreover, they have shortcomings with regard to impedance mismatching, the unequal number of turns which lead to inaccurate results in per phase equivalent circuits, which results in an imbalance output in phase voltages and currents. Therefore, this paper aims to investigate multi-phase power transformation from a three-phase system and examine the different static multiphase transformation techniques. In line with this matter, this study outlines various theories and configurations of transformers, including three-phase to five-, seven-, eleven-, and thirteen-phase transformers. Moreover, the review discusses impedance mismatching, voltage unbalance, and per phase equivalent circuit modeling and fault analysis in multi-phase systems. Moreover, various artificial intelligence-based optimization techniques such as particle swarm optimization (PSO) and the genetic algorithm (GA) are explored to address various existing issues. Finally, the review delivers effective future suggestions that would serve as valuable opportunities, guidelines, and directions for power engineers, industries, and decision-makers to further research on multi-phase transformer improvements towards sustainable operation and management.This work was supported by the Universiti Kebangsaan Malaysia under Grant Code GP-2021-K023221. This work also received partial financial support from Universiti Kebangsaan Malaysia under Grant Code GGPM-2020-006.Scopu

The application of multiphase DEM for the prediction of fat, oil and grease (FOG) deposition in sewer pipe lines

Fat oil and grease (FOG) deposition into sewer pipes can block the pipes and restrict the wastewater flow causing backflows and sanitary sewer overflows (SSOs). Understanding the wastewater flow and transport of FOG particles is a key step for predicting the particles deposition and blockage formation. ANSYS FLUENT was used for simulating the flow of FOG particles and its deposition onto the sewer pipe. The multiphase Eularian-Lagrangian model with discrete Phase method (DPM) was utilized for developing the CFD model. The kinetic parameters and physical values are based on previous experimental work and literature. The CFD Eularian-DEM multiphase model has shown a good potential for simulating the wastewater flow and demonstrated the applicability of CFD to simulate and track the transport and deposition of FOG particles into the sewer pipe walls