491 research outputs found
Modeling and Protection Scheme for IEEE 34 Radial Distribution Feeder with and Without Distributed Generation
The existing power system was not designed with distribution generation (DG) in mind. As DG penetration is being considered by many distribution utilities, there is a rising need to address many incompatibility issues which puts a big emphasis on the need to review and implement suitable protection scheme. The usual practice for existing distribution feeders is the Overcurrent scheme which includes coordination between fuses and reclosers. But when DG is added to the distribution feeder, the configuration is no more radial as there is contribution of fault currents from the DG\u27s and if the existing protection scheme is applied then this could lead to various issues like fuse misoperation or nuisance tripping considering temporary and permanent fault conditions.
This thesis presents a study on the modeling of existing IEEE 34 radial distribution feeder and scaling of the system from 24.9kV to 12.47kV keeping in mind the existing conditions and also proposes a protection scheme with and without the addition of DG\u27s to the feeder nodes. The protection scheme involves providing appropriate relaying with suitable fuse selection and Current transformer settings. Considerations for proper transformer grounding and capacitor bank fusing protection is also simulated and reviewed. When DG\u27s added, the results show increase in fault contribution and hence causing misoperations which needs to avoided. Relaying considerations are also provided when an islanded mode occurs. The entire analysis has been simulated by a combination of various tools like Aspen One liner, CYMDist and Wavewin with occasional simulations and calculations performed in MATLAB environment
EFFICIENT MICROPROPAGATION FROM COTYLEDONARY NODE CULTURES OF COMMIPHORA WIGHTII (ARN.) BHANDARI, AN ENDANGERED MEDICINALLY IMPORTANT DESERT PLANT
Commiphora wightii (Arn.) Bhandari, is a medicinal important desert species of the family Burseraceae. It is a well known for its valuable active principle found in its oleo-gum-resin (guggulsterone E and Z), which are used in drugs preparation for lowering the cholesterol level in human body. Due to its overexploitation, poor natural regeneration this valuable plant is on the verge of extinction and thus a IUCN Red listed species. In the present study we report development of an efficient micropropagation protocol from cotyledonary node of Commiphora wightii. Cotyledonary nodes were used as an explants and multiple microshoots were obtained on Murashige & Skoog (MS) medium supplemented with 2.68 ”M a-Naphthalene acetic acid (NAA) and 4.44 ”M 6-Benzylamino purine (BAP) and on 2.68 ”M NAA; 4.44 ”M BAP with additives (glutamine 684.2 ”M; thiamine 29.65 ”M; activated charcoal 0.3%) and various other hormonal combinations. Elongation of microshoot was significantly observed on the 2.46 ”M Indole-3-butyric acid (IBA) and 2.22 ”M BAP supplemented MS medium. Efficient rooting was obtained on pretreated microshoot (4.92 ”M IBA for 24 hours) and followed by transfer to Whiteâs medium without Plant Growth Regulators (PGR) and high concentration of activated charcoal (AC). Rooted micro-shoots were transferred to vermiculite and wetted with Hoaglandâs solution for primary hardening for 4-5 weeks and then finally transferred to plastic cups containing vermiculite, placed in mist chamber. Plantlets were transferred to soil: FYM 1:1 containing poly-bags, then to green shade house for complete acclimatization and finally transplanted to the experimental field
Releasable Suture versus Autologous Blood for Pterygium Surgery using Conjunctival Autografts
Purpose: To evaluate the efficacy of releasable single suture (RS) for conjunctival autograft (CAG) and to compare it with sutureless gluefree (SG) technique in pterygium surgery.
Methods: We conducted a retrospective comparative study on patients with primary pterygium who underwent CAG. In 150 patients, CAG was additionally secured by a single 10-0 nylon releasable suture (RS) which was released on the first postoperative day. In 47 patients, no suture was applied, and CAG was allowed to stick to the scleral bed by autologous fibrin only (SG group). The duration of surgery and size of CAG (in mm2) was noted in both groups. All patients completed one year of follow-up. Factors that were studied included graft stability, patient comfort, complications, and recurrence.
Results: The mean age of patients in RS and SG groups was 39.6 ± 11.8 and 47.3 ± 13.8 years, respectively. The mean duration of surgery was 4.84 ± 1.34 min in RS group and 4.90 ± 1.42 min in SG group (P = 0.001). The size of CAG used in both groups was comparable with more stability in RS group postoperatively. Graft retraction rate in RS group was 5.3% (1 mm retraction in CAG more than 36 mm2) with no event of graft loss. The graft loss occurred in 6.3% of eyes in SG group. The recurrence rate in RS group was 4%, while in SG group it was 6.3% (P = 0.4).
Conclusion: RS, by augmenting the autologous blood mechanism, may offer an easy-to-learn option for pterygium surgery with good stability even in large-sized CAGs
Authorship pattern and growth of scholar contributions for PHFI: A Bibliometric Analysis
The purpose of this research study is to identify the authorship patterns and degree of collaboration and growth of Public health foundation of India in Public Health research related with a total of 1941 records of publications authored by 12523 authors during the period 2011â 2020 derived from SCOPUS database. Validation of determine chronological growth, authorship pattern, core sources for research communication, and encouragement of productivity by citations received, various indicators, and indices and bibliometric laws i.e. Authorship pattern, RGR, Dt, CAI, DC, Bradfordâs Law of distributions, and more have been applied appropriately. Additionally, used deferent software of like âMS-Excelâ and âbibliometrixâ & âbiblioshinyâ of R-Package software and VOSviwer software applied for detailed and reliable analysis. Evaluated data figured out Average yearly contribution 194 research however accounted Mean RGR(P) â0.34â; Mean Dt (P) â2.74 reveals inconsistent growth of research output. Average of âCollaboration indexâ (CI) â5.60â A total Average yearly citations were received for research occurrence in the span with an average of 10.46, Prabhakaran. D., was published highest papers 260 and got received highest citation also 4958 and total link strength 1457. For PHFI and individual research scholars. PHFI has to make more effort to promote research and create quality culture, attention of developing better policies to enhance and enrich the research performance of individuals
Bibliometric study of SAARC Countries Research Trends in Public Health using Scopus database
Public health is facing a current covid-19 crisis situation in the world. This study aims to analyze particular the South Asian Association for Regional Cooperation (SAARC) countries\u27 public health research interest and growth. This bibliometric study selected the Public Health keyword from Scopus database geographical area selected was only SAARC countries in the title only and retrieved 1720 published articles. The time period selected was from 1957 to March 2021. 5758 authors were identified to published relevant studies on total over an average of 7.34 years in public health. The data retrieval most productive three main publishing countries India, Pakistan, and Bangladesh. Most productive institutions and authors are from India. Bibliometric analysis showed growth in international collaboration with the USA among most SAARC countries. The most productive journal was found to be âIndian Journal of Public Healthâ and the most productive author Ramasam, Y. J having a total of publication 57. This bibliometric analysis provides an inclusive overview of the public health research conducted in SAARC countries, which helps researchers, policy makers, and practitioner better understand the development of public health care and possible practice implications. Future Public health research should be dedicated to filling in the gaps between SAARC Countries health care research
Defending Against Byzantine Attacks in CRNs: PCA-Based Malicious User Detection and Weighted Cooperative Spectrum Sensing
Cognitive radio (CR) technology is a viable solution for assisting secondary users to share the licensed radio spectrum of primary users. Cooperative spectrum sensing (CSS) enhances the accuracy of spectrum sensing in a CR network. However, the effectiveness of CSS can be compromised by malicious users (MUs) who intentionally send false sensing information to the fusion center. This letter focuses on enhancing the CSS performance and detecting the MUs. We propose a machine learning technique to identify and classify MUs in a CR network using the Principal Component Analysis algorithm. The performance of the proposed algorithm in detecting MUs and enhancing CSS performance is validated through simulation experiments
Antioxidant, antiinflammatory and antiinvasive activities of biopolyphenolics
A large number of polyphenolic and heterocyclic compounds, i.e. 4-methylcoumarins, 4-methylthionocoumarins, xanthones, pyrazoles, pyrazolylacrylonitriles, flavones and isoflavones have been tested for their antioxidant activity towards NADPH-catalysed liver-microsomal lipid peroxidation with a view to establish their structure-activity relationship. Inhibition of microsomal lipid peroxidation by 7,8-dihydroxy-4-methylcoumarin (DHMC, 2) and 7,8-diacetoxy-4-methylcoumarin (DAMC, 3) was intriguing. We also found that dihydroxy and diacetoxy derivatives of 4-methylthionocoumarin were more potent in comparison to the corresponding coumarin derivatives in inhibiting TNF-α induced expression of ICAM-1. The effect of nine different xanthones has been examined on the modulation of cytokine-induced expression of ICAM-1 in human endothelial cells. 1,4-Dihydroxyxanthone (10) showed enhanced antioxidant activity as well as the inhibition of the expression of cell adhesion molecules, such as ICAM-1, VCAM-1 and E-selectin on endothelial cells in a concentration and time dependent manner. Antioxidant activity of different pyrazoles and pyrazolylacrylonitriles and antiinvasive activity of flavones and isoflavones against solid tumors have also been studied
Combinatorial approach towards synthesis of 2',3'-dideoxynucleosides and enzyme-catalysed selective hydrolysis of diethyl acetamidomalonate and amides of polyacetoxy aromatic carboxylic acid
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Nitrification Rates Are Affected by Biogenic Nitrate and Volatile Organic Compounds in Agricultural Soils
The processes regulating nitrification in soils are not entirely understood. Here we provide evidence that nitrification rates in soil may be affected by complexed nitrate molecules and microbial volatile organic compounds (mVOCs) produced during nitrification. Experiments were carried out to elucidate the overall nature of mVOCs and biogenic nitrates produced by nitrifiers, and their effects on nitrification and redox metabolism. Soils were incubated at three levels of biogenic nitrate. Soils containing biogenic nitrate were compared with soils containing inorganic fertilizer nitrate (KNO3) in terms of redox metabolism potential. Repeated NH4âN addition increased nitrification rates (mM NO31- produced g-1 soil d-1) from 0.49 to 0.65. Soils with higher nitrification rates stimulated (p < 0.01) abundances of 16S rRNA genes by about eight times, amoA genes of nitrifying bacteria by about 25 times, and amoA genes of nitrifying archaea by about 15 times. Soils with biogenic nitrate and KNO3 were incubated under anoxic conditions to undergo anaerobic respiration. The maximum rates of different redox metabolisms (mM electron acceptors reduced g-1 soil d-1) in soil containing biogenic nitrate followed as: NO31- reduction 4.01 ± 0.22, Fe3+ reduction 5.37 ± 0.12, SO42- reduction 9.56 ± 0.16, and CH4 production (ÎŒg g-1 soil) 0.46 ± 0.05. Biogenic nitrate inhibited denitrificaton 1.4 times more strongly compared to mineral KNO3. Raman spectra indicated that aliphatic hydrocarbons increased in soil during nitrification, and these compounds probably bind to NO3 to form biogenic nitrate. The mVOCs produced by nitrifiers enhanced (p < 0.05) nitrification rates and abundances of nitrifying bacteria. Experiments suggest that biogenic nitrate and mVOCs affect nitrification and redox metabolism in soil
Synthesis of macromolecular systems via lipase catalyzed biocatalytic reactions: applications and future perspectives
Enzymes, being remarkable catalysts, are capable of accepting a wide range of complex molecules as substrates and catalyze a variety of reactions with a high degree of chemo-, stereo- and regioselectivity in most of the reactions. Biocatalysis can be used in both simple and complex chemical transformations without the need for tedious protection and deprotection chemistry that is very common in traditional organic synthesis. This current review highlights the applicability of one class of biocatalysts viz. ââlipasesââ in synthetic transformations, the resolution of pharmaceutically important small molecules including polyphenols, amides, nucleosides and their precursors, the development of macromolecular systems (and their applications as drug/gene carriers), flame retardants, polymeric antioxidants and nanocrystalline solar cells, etc
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