Improved power quality operation of symmetrical and asymmetrical multilevel inverter using invasive weed optimization technique

Low switching frequency pulse width modulation (PWM) technique for modulation and control of multilevel inverter in medium voltage high power applications is preferred in order to reduce the switching losses. In this context, a multilevel inverter operated with Selective harmonics minimization PWM technique offers better quality waveform at reduced switching losses. After the Fourier series analysis, the system of non-linear simultaneous transcendental equations is obtained. These equations are then solved to obtain switching angles to have certain low order harmonics at minimum value and regulation in the fundamental voltage magnitude. In this paper, a novel invasive weed optimization (IWO) technique is proposed to compute switching angles. The proposed technique can compute switching angles for both symmetrical and asymmetrical multilevel inverters. Thus it has superiority over well-known optimization techniques such as GA, PSO, DE, and ACO, etc. Moreover, in certain modulation index ranges, it provides faster convergence and accurate results which have been demonstrated in the paper. The computational results have been verified with the experimental result on the prototype developed in the laboratory. The field programming gate arrays (FPGA) based controller is used to implement the proposed technique. The hardware results have been found in close agreement with the computed results. 2022This publication was made possible by NPRP grant #[ 13S-0108-20008 ] from the Qatar National Research Fund (A member of Qatar Foundation). The statements made herein are solely the responsibility of the authors. The APC of the paper is funded by the Qatar National Library , Doha, Qatar.Scopu

A novel AI approach for optimal deployment of EV fast charging station and reliability analysis with solar based DGs in distribution network

The transportation sector is one of the most prevalent fossil fuel users worldwide. Therefore, to mitigate the impacts of carbon-dioxide emissions and reduce the use of non-environmentally friendly traditional energy resources, the electrification of the transportation system, such as the development of electric vehicles (EV), has become crucial. For impeccable EVs deployment, a well-developed charging infrastructure is required. However, the optimal placement of fast charging stations (FCSs) is a critical concern. Therefore, this article provides a functional approach for identifying the optimal location of FCSs using the east delta network (EDN). In addition, the electrical distribution network’s infrastructure is susceptible to changes in electrifying the transportation sector. Therefore, actual power loss, reactive power loss, and investment cost are three areas of consideration in deploying FCSs. Furthermore, including FCSs in the electricity distribution network increases the energy demand from the electrical grid. Therefore, this research paper recommends integrating solar-based distributed generations (SDGs) at selected locations in the distribution network, to mitigate the burden of FCSs on the system. Hence, making the system self-sustaining and reliable. In addition, the reliability of the distribution system is also analyzed after deploying the FCSs and SDGs. Furthermore, six case studies (CS) have been proposed to deploy FCSs with or without DG integration. Consequently, the active power loss went from 1014.48 kW to 829.68 kW for the CS-6

Optimal location of electric vehicle charging station and its impact on distribution network: A review

At present, the limited existence of fossil fuels and the environmental issues over greenhouse gas emissions have been directly affected to the transition from conventional vehicles to electric vehicles (EVs). In fact, the electrification of transportation system and the growing demand of EVs have prompted recent researchers to investigate the optimal location of electric vehicle charging stations (EVCSs). However, there are numerous challenges would face when implementing EVs at large scale. For instance, underdeveloped EVCSs infrastructure, optimal EVCS locations, and charge scheduling in EVCSs. In addition, the most fundamental EV questions, such as EV cost and range, could be partly answered only by a well-developed EVCS infrastructure. According to the literature, the researchers have been followed different types of approaches, objective functions, constraints for problem formulation. Moreover, according to the approaches, objective functions, constraints, EV load modeling, uncertainty, vehicle to grid strategy, integration of distributed generation, charging types, optimization techniques, and sensitivity analysis are reviewed for the recent research articles. Furthermore, optimization techniques for optimal solution are also reviewed in this article. In addition, the EV load impact on the distribution network, environmental impacts and economic impact are discussed

Socio-Economic Impediments in Usage of Modern Mechanized Technological Ideals in Agriculture Sector: A Case Study of District Lodhran, Punjab-Pakistan

The process of adopting modern mechanized technological ideals encompasses certain aspects such as demographic characteristics, economic stability and societal acceptance regarding advanced methods of farming. The core objective of this research was to explore the role of socio-economic impediments in usage of modern mechanized technological ideals in agriculture sector of district Lodhran, Punjab-Pakistan. The present research was descriptive in nature and structured interview schedule was used to collect the data. A total of 200 small and large-scale farmers were selected through multi-stage sampling technique. Results revealed that 80% of the farmers do not adopt modern technological ideals due to economic instability, 35% of farmers reported that no person came into their area for guiding and training them regarding modern machinery and 62.5 % stated that there were cultural barriers behind not coming of trainers. This study concluded that farmers perceived modern mechanism more beneficial for their fields, but socio-economic impediments were playing vital role in hindering the adoption of modern mechanized ideal

A p38MAPK/MK2 signaling pathway leading to redox stress, cell death and ischemia/reperfusion injury

Background Many diseases and pathological conditions are characterized by transient or constitutive overproduction of reactive oxygen species (ROS). ROS are causal for ischemia/reperfusion (IR)-associated tissue injury (IRI), a major contributor to organ dysfunction or failure. Preventing IRI with antioxidants failed in the clinic, most likely due to the difficulty to timely and efficiently target them to the site of ROS production and action. IR is also characterized by changes in the activity of intracellular signaling molecules including the stress kinase p38MAPK. While ROS can cause the activation of p38MAPK, we recently obtained in vitro evidence that p38MAPK activation is responsible for elevated mitochondrial ROS levels, thus suggesting a role for p38MAPK upstream of ROS and their damaging effects.<p></p> Results Here we identified p38MAPKα as the predominantly expressed isoform in HL-1 cardiomyocytes and siRNA-mediated knockdown demonstrated the pro-oxidant role of p38MAPKα signaling. Moreover, the knockout of the p38MAPK effector MAPKAP kinase 2 (MK2) reproduced the effect of inhibiting or knocking down p38MAPK. To translate these findings into a setting closer to the clinic a stringent kidney clamping model was used. p38MAPK activity increased upon reperfusion and p38MAPK inhibition by the inhibitor BIRB796 almost completely prevented severe functional impairment caused by IR. Histological and molecular analyses showed that protection resulted from decreased redox stress and apoptotic cell death.<p></p> Conclusions These data highlight a novel and important mechanism for p38MAPK to cause IRI and suggest it as a potential therapeutic target for prevention of tissue injury.<p></p&gt

Karachi cancer registry (KCR): Age-standardized incidence rate by age-group and gender in a mega city of Pakistan

Objectives: To estimate the cancer incidence by age group and gender for the population of Karachi Division by analyzing the Karachi Cancer Registry data of 2017-19.Settings: The population of Karachi division is 16.1 million according to national census 2017. \u27Karachi Cancer Registry\u27 which is a part of \u27National Cancer Registry\u27 is collecting data from eight major hospitals in Karachi since 2017. For outcome measures, cancer counts and the age standardized incidence rates (ASIR) per 100,000 population were computed for age groups (0-14, 15-19 and ≥20 years), in both genders and all cancer site/type.Methods: The population denominators were based on the population of Karachi division estimated at 16.1 million in the population census, 2017. Counts and age-standardized incidence rates (ASIR) were calculated for each of the three age categories.Results: From Jan 2017 till Dec 2019 a total of 33,309 malignant cases were recorded in KCR database comprising 17,490 (52.5%) females and 15,819 (47.5%) males. ASIRs in age groups 0-14, 15-19 and ≥ 20 years, among female were 11.5, 2.4 and 223.6 and in males were 17.6, 3.2 and 216.7 respectively. The commonest diagnosis in children, adolescent and adults were (1) among females: children; bone (3.12), leukemia (2.09) brain/CNS (1.26); in adolescents: bone (0.78), brain/CNS (0.27), connective and soft tissue (0.11), in adults: breast cancer (76.07), oral cancer (16.68) and ovary (10.89) respectively, and (2) among males: children; bone (4.56), leukemia (2.79) and brain/CNS (1.88); in adolescent; bone (1.19), brain/CNS (0.31) and leukemia (0.21) and in adults: oral cancer (42.83), liver (16.10) and bone (13.37) respectively.Conclusion: Oral Cancer, a largely preventable cancer is the leading cancer in Karachi adult males while in female adults Breast Cancer is the leading cancer followed by Oral Cancer. In children and adolescents Bone, Leukemia and Brain/CNS malignancies are most common.

Alternate efflux pump mechanism may contribute to drug resistance in extensively drug-resistant isolates of mycobacterium tuberculosis

INTRODUCTION: Extensively drug-resistant tuberculosis (XDR-TB) has emerged as one of the biggest threats to public health and TB control programs worldwide. XDR-TB is caused by Mycobacterium tuberculosis (MTB) strains resistant to rifampin and isoniazid, as well as to a fluoroquinolone and to at least one injectable aminoglycoside. Drug resistance in MTB has primarily been associated with single nucleotide polymorphisms (SNPs) in particular genes. However, it has also been shown that efflux pumps may play a role in resistance of MTB. Upregulation of drug efflux pumps can decrease the intracellular concentration of drugs and reduce their efficacy. METHODS: Whole genome sequencing was performed on 32 XDR-TB clinical isolates. Sequence data were used to investigate SNPs in efflux pump genes as compared with the H37Rv reference genome. RESULTS: Of the XDR MTB strains, eight (21.62%) were wild type for rpsL, rrs (500 region), and gidB genes, but had non-synonymous (ns) SNPs (aspartic acid to histidine) in the drrA efflux pump gene at position 3273138. Three of eight (37.5%) XDR MTB strains, wild type for rpsL, rrs (500 region), gidB, and gyrB genes were phenotypically streptomycin sensitive and five (62.5%) XDR MTB strains were streptomycin resistant, while all XDR MTB strains, wild type for rpsL, rrs, gidB, and gyrB genes were resistant to fluoroquinolone (ofloxacin) and ethambutol. In addition, three XDR MTB strains wild type for rpsL, rrs, gidB, and drrA genes showed nsSNPs (isoleucine to valine) in the major facilitator superfamily, Rv1634 efflux pump gene at position 1839306. CONCLUSION: Our data show an nsSNP in the drrA efflux pump gene that may result in upregulation of drug efflux mechanisms in MTB strains. It is therefore imperative to understand the mechanism of efflux and its role in drug resistance, which will enable the identification of new drug targets and development of new drug regimens to counteract the drug efflux mechanism of MTB

A mixed methods study to assess the effectiveness of food-based interventions to prevent stunting among children under-five years in districts Thatta and Sujawal, Sindh province, Pakistan: study protocol

Background: Maternal and child malnutrition is widely prevalent in low and middle income countries. In Pakistan, widespread food insecurity and malnutrition are the main contributors to poor health, low survival rates and the loss of human capital development. The nutritional status trends among children exhibit a continuous deteriorating with rates of malnutrition exceeding the WHO critical threshold. With the high prevalence of maternal and child malnutrition, it is important to identify effective preventative approaches, especially for reducing stunting in children under-five years of age. The primary aim of this study is to assess the effectiveness of food-based interventions to prevent stunting in children under-five years. Methods: A mixed methods study design will be conducted to evaluate the effectiveness of food-based interventions to prevent stunting among children under-five years in districts Thatta and Sujawal, Sindh Province, Pakistan. The study will include cross sectional surveys, a community-based cluster randomized controlled trial and a process evaluation. The study participants will be pregnant women, lactating mothers and children under-five years. The cross-sectional surveys will be conducted with 7360 study participants at baseline and endline. For the randomized control trial, 5000 participants will be recruited and followed monthly for compliance of food-based supplements, dietary diversity, pregnancy outcomes, and maternal and child morbidity and mortality. Anthropometric measurements and hemoglobin levels will be measured at baseline, quarterly and at endline. The interventions will consist of locally produced lipid-based nutrient supplement (Wawamum) for children 6–23 months, micronutrient powders for children 24–59 months, and wheat soya blends for pregnant and lactating mothers. Government lady health workers will deliver interventions to participants. The effectiveness of the project will be measured in terms of the impact of the proposed interventions on stunting, nutritional status, micronutrient deficiencies, and other key indicators of the participants. The process evaluation will assess the acceptability, feasibility and potential barriers of project implementation through focus group discussions, key informant interviews and household surveys. Data analysis will be conducted using STATA version 12. Discussion: There is considerable evidence on the effectiveness of food-based interventions in managing stunting in developing countries. However, these studies do not account for the local environmental factors and widespread nutrient deficiencies in Pakistan. These studies are often conducted in controlled environments, where the results cannot be generalized to programs operating under field conditions. The findings of this study will provide sufficient evidence to develop policies and programs aimed to prevent stunting in children 6–59 months and to improve maternal and child health and growth outcomes in poor resource setting

Interactive effects of vanadium and phosphorus on their uptake, growth and heat shock proteins in chickpea genotypes under hydroponic conditions

The present study was carried out to examine the interaction of vanadium and phosphorus and changes in heat shock genes to optimize the growth of chickpea genotypes. Two sets of hydroponic experiments were carried out using vanadium and phosphorus with five-level central composite design. Five levels of vanadium (0-1180 mu M) and phosphorus (0-100011 mu M) were used to evaluate their interactive effects. Plants fresh biomass and uptake of vanadium and phosphorus were influenced by vanadium and phosphorus application. Enhanced fresh biomass was most likely a result of increased phosphorus uptake by chickpea genotypes. Addition of vanadium induced toxic effects while, higher concentration of phosphorus alleviated its toxic effects. The obtained results also indicated that lower vanadium concentration promoted phosphorus absorption however; higher concentration of vanadium inhibited the phosphorus uptake. The morphological changes in leaves indicated that the cells were deformed and reduced in size when treated with higher vanadium levels with fixed phosphorus while, there was little deformation and reduction in cells size were observed when plants were treated with higher levels of phosphorus with fixed vanadium. Whereas, the proportion of deformation of cells were higher in Balkasar as compared to C-44 genotype. The results also showed that at elevated vanadium with fixed phosphorus, Hsp70 was expressed only in C-44 while, not in Balkasar however, Hsp90 and GAPDH showed non-significant results. (C) 2016 Elsevier B.V. All rights reserved

Clinical and electrophysiological efficacy of leaf extract of Gingko biloba L (Ginkgoaceae) in subjects with diabetic sensorimotor polyneuropathy

Purpose: To investigate the health benefits of Gingko biloba L. leave extract EGb 761 in patients with diabetic sensorimotor polyneuropathy (DSP).Method: In a randomized, double-blind, placebo trial, patients (n = 156) received Gingko biloba (120 mg/day) or placebo for 6 months. Efficacy of Gingko biloba extract EGb 761 was assessed on the reduction in the scores of “Short-Form McGill Pain Questionnaire” (SF-MPQ) and improvements in latency, amplitude and conduction velocity of four sensory (ulnar, median, peroneal and sural) and four motor (ulnar, median, peroneal and tibial) nerves.Results: Gingko biloba significantly improved the mean scores of sensory, affective, visual analogue score (VAS) and present pain intensity (PPI) of SF-MPQ on 3 and 6 month post-treatment. At the start of experiment in the Gingko biloba-treated group, scores for sensory, affective, VAS and PPI domains were 12.90 ± 7.21, 4.40 ± 1.79, 4.38 ± 1.69 and 3.24 ± 0.78 respectively. After 6-months treatment with Gingko biloba, scores for sensory, affective, VAS and PPI domains were reduced (p < 0.01) to 7.24 ± 4.91, 3.11 ± 1.81, 3.37 ± 1.35 and 2.45 ± 0.65 respectively. Contrarily, in the placebo-administered group, sensory domain was (p < 0.01) deteriorated after 6 month (4.70 ± 1.87) compared to the baseline (4.04 ± 1.67). Gingko biloba extract EGb 761 failed to influence the electrophysiological measures when compared with the placebo group. The common adverse effects observed with Gingko biloba were somnolence and dryness of mouth compared with the placebo-treated patientsConclusion: Gingko biloba extract EGb 761 seems to be an effective and safe drug for reducing symptoms of DSP without any apparent effect on the electrophysiological attributes of sensorimotor nerves.Keywords: Diabetic polyneuropathy, Diabetes mellitus, Electrophysiological parameters, Gingko biloba, Sensorimotor nerves, Short-Form McGill Pain Questionnair