Mitigation of Power Quality Problems Using Custom Power Devices: A Review

Electrical power quality (EPQ) in distribution systems is a critical issue for commercial, industrial and residential applications. The new concept of advanced power electronic based Custom Power Devices (CPDs) mainly distributed static synchronous compensator (D-STATCOM), dynamic voltage restorer (DVR) and unified power quality conditioner (UPQC) have been developed due to lacking the performance of traditional compensating devices to minimize power quality disturbances. This paper presents a comprehensive review on D-STATCOM, DVR and UPQC to solve the electrical power quality problems of the distribution networks. This is intended to present a broad overview of the various possible DSTATCOM, DVR and UPQC configurations for single-phase (two wire) and three-phase (three-wire and four-wire) networks and control strategies for the compensation of various power quality disturbances. Apart from this, comprehensive explanation, comparison, and discussion on D-STATCOM, DVR, and UPQC are presented. This paper is aimed to explore a broad prospective on the status of D-STATCOMs, DVRs, and UPQCs to researchers, engineers and the community dealing with the power quality enhancement. A classified list of some latest research publications on the topic is also appended for a quick reference

Performance Evaluation of Three Different Inverter Configurations of DVR for Mitigation of Voltage Events

The voltage events namely voltage sags and voltage swells represent the most common, frequent and important power quality events in today’s power system. Dynamic voltage restorer (DVR) is one of the key components used to mitigate the supply voltage quality disturbances in terms of voltage sags and swells in the distribution system. It consists of an energy storage unit, a voltage source inverter, a filter, a coupling transformer and the control system. This paper presents three different inverter configurations of dynamic voltage restorer (DVR) for mitigation of voltage events such as voltage sags and swells with sudden addition or removal of the nonlinear load. These three configurations are voltage source inverter based DVR (VSI-DVR), current source inverter based DVR (CSI-DVR) and impedance or Z-source inverter based DVR (ZSI-DVR). The d-q control technique is used to control the operation of the DVR. The response of ZSI-DVR for mitigation of voltage sags and swells are investigated and compared with VSI-DVR and CSI-DVR using MATLAB/SIMULINK environment

Biocatalytic route to C-3?-azido/-hydroxy-C-4?-spiro-oxetanoribonucleosides

The lipase, Novozyme®-435, exclusively deacetylates the 5-O-acetyl over 4-C-acetyloxymethyl group of almost identical reactivity in 5-O-acetyl-4-C-acetyloxymethyl-3-azido-3-deoxy-1,2-O-isopropylidene-?-D-ribofuranose that led to the development of first and efficient synthesis of 3?-azido-/3?-amino-C-4?-spiro-oxetanoribonucleosides T, U, C and A in 20–24% overall yields. The X-ray study on the compound obtained by tosylation of lipase-mediated monodeacetylated product unambiguously confirmed the point of diastereoselective monodeacetylation on diacetoxy-azido-ribofuranose derivative. The capability of Novozyme®-435 for selective deacylation of 5-O-acetyl group in 5-O-acetyl-4-C-acetyloxymethyl-3-O-benzyl-1,2-O-isopropylidene-?-D-ribofuranose recently discovered by us has been successfully used for the synthesis of C-4?-spiro-oxetanoribonucleosides A and C in good yields. These results clearly indicate that the broader substrate specificity and highly selective capability of Novozyme®-435 for carrying out acetylation/deacetylation reactions can be utilized for the development of environment friendly selective methodologies in organic synthesis

Pathya & Apathya (Wholesome & Unwholesome diet and regimen) in Yakrit Kshaya (Liver Cirrhosis) : A Narrative Review

Yakrit Kshaya (Liver Cirrhosis) is associated with vitiated Agni (digestive power), production of Ama (Undigested food) and Anuloma and Pratilomakshyaya (forward and backward depletion of Dhatu). Approximate 20% compensated cirrhosis patients and 65-95% decompensated cirrhosis patient have either Anuloma Dhatu Kshaya (forward depletion) or Pratilomana Dhatu Kshaya (backward depletion) or both types of malnutrition. Pathya (wholesome diet and regimen) is defined as the Ahara (Diet) and Vihara (regimen) that give proper nutrition to body and mind, clear the micro channels of Body (Pantha/Marga/Srotas), and provide happiness; that opposite is Apathya(unwholesome diet and regimen). A Pathya and Apathya chart for Yakrit Kshaya (Liver Cirrhosis) is prepared and presented. Chinta (anxiety), Shoka (depression), Krotha (anger), Duhkha (sorrow), Dukkha Shaiya (uncomforted bed) and Ratrijagarana (insomnia) can contribute for the indigestion even if a small quantity of Pathyaahara (wholesome diet). Normal diet with Goghruta (ghee) prepared from curd (Emulsified fat), Mamsa Rasa, milk can balance the protein. The Yakrit Kshaya patients should eat 6-8 times in small quantity (snax, mini meal ) as their Agni is low to very low. Mid night meal is also advisable for reduce protein breakdown. Restriction of water, sour and salty foods, fast foods are very crucial for the treatment outcome as it create Ama. More research on Pathya (Ayurveda diet) in Yakritkshaya (Liver cirrhosis) is encouraged

Drug utilization pattern in an intensive care unit setting in Eastern India

Background: The intensive care unit (ICU) is a setting where a large number of drugs are administered to patients, most of them critically ill and suffering from multiple complications, making the costs of hospitalization and drug treatment high. There is a dearth of information on drug utilization in ICUs in Eastern India. The present study was undertaken to evaluate the drug utilization pattern in an ICU setting in Eastern India. The objective was to monitor, evaluate, and suggest modifications in the prescribing pattern of ICU drugs.Methods: A retrospective analysis of the case records of patients admitted to the ICU of a multispecialty hospital in Eastern India during the time period from January 2015 to June 2015 was carried out. The demographic profile of the patients, drug utilization pattern and defined daily dose (DDD)/100 bed-days of the commonly used drugs in the ICU were studied.Results: A total of 275 patients were evaluated consisting 61% male patients. Most common causes for admission to the ICU were a cerebrovascular accident, chronic kidney disease, and road traffic accident. An average number of drugs per patient was 10.5. Commonly prescribed drug classes were the antimicrobial agents (AMAs) in 96% patients followed by gastrointestinal drugs. Ceftriaxone was the most commonly used AMA (41.5% patients), having a drug consumption of 35.1 DDD/100 bed-days during the study period.Conclusions: An antibiotic use policy should be framed and followed to curb the excessive use of AMAs. Formation of a multidisciplinary team to oversee drug use will be helpful to make the drug utilization in the ICU rational

Isolation and structure elucidation of novel compounds from stem of Dendrophthoe falcata

Dendrophthoe falcata (syn. with Loranthus falcatus) has been widely used in Indian and other traditional medicine systems as a therapeutic herb. Extensive pharmacological studies of leaf and stem extracts of D. falcata have shown significant biological activities. In the present study, an attempt has been made to carry out the phytochemical investigation of the petroleum ether and dichloromethane extract of the stem part of D. falcata, collected from Assam, situated in the eastern part of India, with the purpose of isolating and identifying the possible bioactive phytochemicals of this plant towards the development of new pharmaceutical products. Using repeated coloumn chromatography, preparative TLC and crystallization techniques, ten compounds were isolated in pure form. On the basis of detailed spectral studies they were identified as di-iso-octylphthalate 1, nonadecan-1-ol 2, stigmast-4-en-3-one 3, stigmast-5-en-3β-ol 4, stigmast-5,22-E-dien-3β-ol 5, 3β-hydroxylup-20(29)-en-28-oic acid 6, 3β-hydroxyolean-12-en-28-oic acid 7, 7-hydroxy-4',5,6-trimethoxyflavone 8 , 2,3-dihydro-4-hydroxy-3,6,9-trimethylnaphtho[1,8-bc]pyran-7,8-dione 9 and 4-hydroxy-3-methoxybenzoic acid 10. Compounds 1,4,5,7 and 10 have previously been reported from Dendrophthoe species. This is the first report of compounds 2,3,6,8 and 9 from Dendrophthoe species and the first report of 8 from natural source. Further research work is needed on these identified compounds to explore their usefulness in phytopharmaceutical products

Occurrence of anemia among the people of Gurugram, Haryana: a cross sectional study

Anemia is considered a condition, not a disease in which numbers of red blood cells (RBCs) are insufficient to meet the body’s metabolical and physiological needs for oxygen. Anemia may also develop due to nutritional deficiencies such as iron, vitamin B12, folic acid, and vitamin A; moderate and severe inflammation; parasitic infestation; and acquired or inherited disorders that affect hemoglobin synthesis, red blood cell development or red blood cell endurance. This proposed work depicts the distribution of different morphological types of anemia on people of Gurugram, Haryana. All the samples were analyzed for CBC and peripheral blood smear by using Sysmax (three parts) hematology analyzer and microscopy.  In the present study, 300 patients in 6 months study period were included to diagnose anemia. Only 166 cases were positive. Out of 166 cases, 85 (51.2%) were female and 81 (48.8%) were male. The highest number of participants showed RBCs count in the range of 4.5-5.5 million/mm3, 24 (14.5%) with P value 0.000. Most of the cases that we revealed were having hypochromic red cells along with morphological variation in RBCs which may be due to iron deficiency. The further confirmatory analysis may be required in order to know the detail classification of anemia. Keywords: Anemia, Hemoglobin, Iron Deficiency, Hypochromic, Red Blood Cell