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      • KCI등재

        Enhanced Production of δ-Aminolevulinic Acid, Bilipigments, and Antioxidants from Tropical Algae of India

        Usha Pandey1,Jitendra Pandey 한국생물공학회 2009 Biotechnology and Bioprocess Engineering Vol.14 No.3

        We studied the enhanced production of high quality biomass, δ-aminolevulinic acid (δ-ALA), bilipigments, and antioxidants from five tropical blue green algae (cyanobacteria) in a full factorial design using free and immobilized cells in batch culture. Production of nutraceuticals was high in spray dried powder prepared from immobilized cell cultures. Notochopsis lobatus showed superiority over rest of the species with respect to bilipigments, δ-ALA, nutritive value, antioxidant capacity, and ascorbate oxidase (APX) activity. Antioxidative capacity of phycobiliproteins extracted from these cyanobacteria (121.15 μM TE/g, Nostoc verrucosum to 217.62 μM TE/g, Nostochopsis lobatus) was invariably higher than those observed for higher plant sources and substantially increased under immobilized cell culture condition. Antioxidative enzyme, ascorbate oxidase remained stable in dry food preparations with considerably high activity under immobilized cell preparations (APXmax, 3.40 μmol/min/mg chlorophyll). These observations have important connotations in light of upcoming food and nutraceutical industries in the global market. Use of immobilized cells in batch culture could be an effective approach for scaling up production for commercial use We studied the enhanced production of high quality biomass, δ-aminolevulinic acid (δ-ALA), bilipigments, and antioxidants from five tropical blue green algae (cyanobacteria) in a full factorial design using free and immobilized cells in batch culture. Production of nutraceuticals was high in spray dried powder prepared from immobilized cell cultures. Notochopsis lobatus showed superiority over rest of the species with respect to bilipigments, δ-ALA, nutritive value, antioxidant capacity, and ascorbate oxidase (APX) activity. Antioxidative capacity of phycobiliproteins extracted from these cyanobacteria (121.15 μM TE/g, Nostoc verrucosum to 217.62 μM TE/g, Nostochopsis lobatus) was invariably higher than those observed for higher plant sources and substantially increased under immobilized cell culture condition. Antioxidative enzyme, ascorbate oxidase remained stable in dry food preparations with considerably high activity under immobilized cell preparations (APXmax, 3.40 μmol/min/mg chlorophyll). These observations have important connotations in light of upcoming food and nutraceutical industries in the global market. Use of immobilized cells in batch culture could be an effective approach for scaling up production for commercial use

      • KCI등재

        Meconium Peritonitis: A Rare Treatable Cause of Non-Immune Hydrops

        Usha Devi Rajendran,Jeyanthi Govindarajan,Umamaheswari Balakrishnan,Ashok Chandrasekaran,Prakash Amboiram 대한소아소화기영양학회 2019 Pediatric gastroenterology, hepatology & nutrition Vol.22 No.6

        Meconium peritonitis as a cause of non-immune hydrops in neonates is rarely reported. Here we report such a rare occurrence. In our case, a routine antenatal scan at 25 weeks revealed isolated ascites. By 31 weeks of gestation, all features of hydrops were observed in scans. However, antenatal workup for immune and non-immune hydrops was negative. Subsequently, a preterm hydropic female baby was delivered at 32 weeks. She required intubation and ventilator support. An X-ray revealed calcification in the abdomen suggestive of meconium peritonitis. Ultrasound showed gross ascites, a giant cyst compressing the inferior vena cava, and minimal bilateral pleural effusion. Emergency laparotomy revealed meconium pellets and perforation of the ileum. Double-barrel ileostomy was performed, and the edema resolved and activity improved. The baby was discharged after 3 weeks. Ileostomy closure was done at follow-up. The baby is growing well.

      • KCI등재

        An Experimental Fault Analysis and Speed Control of an Induction Motor using Motor Solver

        Usha Sengamalai,Subramani Chinnamuthu 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.2

        This paper deals with the performance analysis of three phase induction motor considering its stator side faults and operating thermal limits. The speed control of induction motor using three phase boost converter operated by a MOSFET switch and a PI controller is demonstrated and presented in this article. IGBTs switches are used for inverter drive mechanism .The experimental result of speed control of induction motor using voltage control technique clearly shows better accuracy than conventional methods of speed control. A three phase 1HP 415V 0.78 kW 4 Pole induction motor is designed using motor solver software. Based on the parameters used in the software thermal analysis of induction motor is done and torque variation with conductor area, efficiency, output curve, losses in different parts of motor has been obtained. Also different types of faults namely under voltage, over voltage, stator imbalanced voltage, turn to turn, locked rotor bar, wrong alignment of rotor bar with respect to stator are studied and fault analysis is performed. Hence comparison is made based upon the results obtained before and after faults.

      • KCI등재

        Trees, unicyclic graphs extremal with respect to Kekule index

        Usha.A,P. S. Ranjini,V.Lokesha 장전수학회 2014 Advanced Studies in Contemporary Mathematics Vol.24 No.3

        For a molecular graph G with vertex set V(G) and edge set E(G), recently Lavanya, [1] introduced a new topologial index, the Kekule index is defined as (formula) where, (formula) and i and j are the degrees of the vertices u and v respectively. In this paper, we characterize the trees and unicyclic graphs extremal with respect to Kekule index.

      • Interaction of Resveratrol and Genistein with Nucleic Acids

        Usha, Subbiah,Johnson, Irudayam Maria,Malathi, Raghunathan Korean Society for Biochemistry and Molecular Biol 2005 Journal of biochemistry and molecular biology Vol.38 No.2

        Resveratrol (RES) and genistein (GEN) are the dietary natural products known to possess chemopreventive property and also the ability to repair DNA damage induced by mutagens/carcinogens. It is believed that the therapeutic activity of these compounds could be primarily due to their interaction with nucleic acids but detailed reports are not available. We here explore the interaction of these drugs with nucleic acids considering DNA and RNA as a potential therapeutic target. The interaction of RES and GEN has been analysed in buffered solution with DNA [saline sodium citrate (SSC)] and RNA [tris ethylene diammine tetra acetic acid (TE)] using UV-absorption and Fourier transform infrared (FTIR) spectroscopy. The UV analysis revealed lesser binding affinity with nucleic acids at lower concentration of RES (P/D = 5.00 and 10.00), while at higher drug concentration (P/D = 0.75, 1.00 and 2.50) hyperchromic effect with shift in the ${\lambda}_{max}$ is noted for DNA and RNA. A major RES-nucleic acids complexes was observed through base pairs and phosphate backbone groups with K = $35.782\;M^{-1}$ and K = $34.25\;M^{-1}$ for DNA-RES and RNA-RES complexes respectively. At various concentrations of GEN (P/D = 0.25, 0.50, 0.75, 1.00 and 2.50) hyperchromicity with shift in the ${\lambda}_{max}$ from 260 $\rightarrow$ 263 om and 260 $\rightarrow$ 270 nm is observed for DNA-GEN and RNA-GEN complexes respectively. The binding constant (from UV analysis) for GEN-nucleic acids complexes could not be obtained due to GEN absorbance overlap with that of nucleic acids at 260 nm. Nevertheless a detailed analysis with regard to the interaction of these drugs (RES/GEN) with DNA and RNA could feasibly be understood by FTIR spectroscopy. The NH band of free DNA and RNA which appeared at $3550-3100\;cm^{-1}$ and $3650-2700\;cm^{-1}$ shifted to $3450-2950\;cm^{-1}$ and $3550-3000\;cm^{-1}$ in DNA-RES and RNA-RES complexes respectively. Similarly shifts corresponding to $3650-3100\;cm^{-1}$ and $3420-3000\;cm^{-1}$ have been observed in DNA-GEN and RNA-GEN complexes respectively. The observed reduction in NH band of free nucleic acids upon complexation of these drugs is an indication of the involvement of the hydroxyl (OH) and imino (NH) group during the interaction of the drugs and nucleic acids (DNA/RNA) through H-bonded formation. The interaction of RES and GEN with bases appears in the order of G $\geq$ T > C > A and A > C $\geq$ T > G. Further interaction of these natural compounds with DNA and RNA is also supported by changes in the vibrational frequency (shift/intensity) in symmetrical and asymmetrical stretching of aromatic rings of drugs in the complex spectra. No appreciable shift is observed in the DNA and RNA marker bands, indicating that the B-DNA form and A-family conformation of RNA are not altered during their interaction with RES and GEN.

      • KCI등재

        Assessment of Low Intensity Solar Radiation Susceptibility in 20 Wheat Varieties under Field Conditions Grown in Indo-Gangetic Plains of India

        Usha Mina,S.D. Singh,B. Singh,Deepak Singh,S. Tiwari,Pranav Kumar 한국작물학회 2019 Journal of crop science and biotechnology Vol.22 No.3

        Wheat productivity declines under agro-ecosystems and areas exposed to aerosols due to decline in quality and quantity of solar radiation. Identification of low light-tolerant wheat varieties (Triticum sps.) will help in enhancing the sustainability and productivity of the agroforestry systems as well as areas exposed to aerosol pollution. The field study was conducted to assess the effects of low intensity solar radiation (LR) on 20 wheat varieties in terms of growth, stay green, gaseous exchange, yield attributes, and tolerance indices. Results indicate the increase in plant height and leaf area, reduction in photosynthesis (Pn), stomatal conductance (gs), and transpiration (Tr) in all the varieties grown under LR compared to normal radiation. The varieties, K68 and HD2643, exhibited maximum stay green compared to other varieties. LR caused reduction in biological (35%) and economic (46%) yield of wheat. Among the indices, mean productivity (MP), geometric mean (GM), stress tolerance index (STI), and yield index (YI) were positively correlated with grain yield under LR (Ys) and NR (Yp). Cluster analysis indicated that varieties-HD2643, K68, Kalyansona, and C306 varieties were most LR tolerant, while DL1266-1, DL1266-2, and Moti were moderately tolerant and rest of the varieties exhibited LR susceptibility.

      • KCI등재

        Assessment of Low Intensity Solar Radiation Susceptibility in 20 Wheat Varieties under Field Conditions Grown in Indo-Gangetic Plains of India

        Usha Mina,S.D. Singh,B. Singh,S. Tiwari,Deepak Singh,Pranav Kumar 한국작물학회 2018 Journal of crop science and biotechnology Vol.21 No.4

        Wheat productivity declines under agro-ecosystems and areas exposed to aerosols due to decline in quality and quantity of solar radiation. Identification of low light-tolerant wheat varieties (Triticum sps.) will help in enhancing the sustainability and productivity of the agroforestry systems as well as areas exposed to aerosol pollution. The field study was conducted to assess the effects of low intensity solar radiation (LR) on 20 wheat varieties in terms of growth, stay green, gaseous exchange, yield attributes, and tolerance indices. Results indicate the increase in plant height and leaf area, reduction in photosynthesis (Pn), stomatal conductance (gs), and transpiration (Tr) in all the varieties grown under LR compared to normal radiation. The varieties, K68 and HD2643, exhibited maximum stay green compared to other varieties. LR caused reduction in biological (35%) and economic (46%) yield of wheat. Among the indices, mean productivity (MP), geometric mean (GM), stress tolerance index (STI), and yield index (YI) were positively correlated (P ≤ 0.05) with grain yield under LR (Ys) and NR (Yp). Cluster analysis indicated that varieties – HD2643, K68, Kalyansona, and C306 varieties were most LR tolerant, while DL1266-1, DL1266-2, and Moti were moderately tolerant and rest of the varieties exhibited LR susceptibility.

      • KCI등재

        모국어 말소리 대조 시 작업기억과 변별능력 간의 연관성

        Usha Shastri,Keerthana Kulath Purath Raj,Mable Mathew,Mohan Kumar Kalaiah,Ajith Kumar Uppunda c 한국언어청각임상학회 2019 Communication Sciences and Disorders Vol.24 No.1

        배경 및 목적: 모국어의 말소리(phone)를 변별할 때, 특히 도전적 상황에서 이를 수행할 때에는 매우 큰 개인차가 존재한다. 말소리 변별 시 유용한 단서를 활용할 수 있는 능력이 인지능력에 의해 촉진되는지, 이를 통해 개인차를 어느 정도 설명해 줄 수 있는지에 대해서는 잘 알려져 있지 않다. 본 연구는 말라얄람어(Malayalam)를 모국어로 사용하는 청자가 말라얄람어 말소리를 맥락 단서 없이 구분할때 작업기억능력과 변별능력 간에 어떤 연관성이 있는지 알아보고자 하였다. 방법: 말라얄람어를 모국어로 사용하는 18-25세 청자 40 명이 본 연구에 참여하였다. 참여자들로 하여금 무의미단어 사이에 삽입된 말라얄람어 8개 말소리를 변별하도록 하였다. 읽기폭 과제, 조작폭 과제, 숫자 바로외우기 과제, 숫자 거꾸로외우기 과제 등을 이용하여 작업기억능력을 측정하였고, 각 말소리의 변별점수, 전체 말소리 변별점수(8개 말소리로부터 얻은 평균변별점수)와 변별 시 반응시간을 함께 측정하였다. 결과: 참여자의 말소리 변별점수는 57.8%-99%의 범위를 보였다. 피어슨 적률상관분석 결과 모든 작업기억능력 측정치와 전체 말소리 변별점수 간에는 유의한 정적 상관이 나타나 작업기억능력이 말소리 변별에 중요한 역할을 하는 것으로 나타났다. 작업기억능력의 측정치는 말소리 변별점수 다양성의 24.7%를 설명할 수 있었다. 논의 및 결론: 맥락 단서가 없는 상황에서의 말소리 변별은 인지 부담을 높인다. 그러므로 높은 능력은 어려운 상황에서 모국어 말소리를 변별하는 데 도움을 준다. 이 연구는 모국어 말소리 지각에서 인지가 미치는 하향식 영향력을 제시하고 있다. Objectives: Large individual variability is documented for identification performance of native phones, especially in challenging situations. It is not known whether the ability to utilize cues available for phone identification is facilitated by cognitive abilities, thereby explaining a proportion of the individual variability. This study investigated the relationship between working memory capacity and identification of a few Malayalam phones in the absence of contextual cues among native listeners. Methods: Forty native listeners of Malayalam, aged between 18 and 25, participated in this study. Participants identified 8 Malayalam phones embedded in nonsense words. Working memory capacity was measured using tasks such as reading span, operation span, digit forward span, and digit backward span. Identification score for each phone, total phone identification score (average identification score from 8 phones), and reaction time during identification were obtained. Results: Phone identification score of participants ranged from 57.8% to 99%. Pearson product moment correlation analysis showed a significant positive correlation between all measures of working memory capacity and total phone identification score, indicating that working memory capacity play a role in the identification of phones. Reaction time showed a significant negative correlation with digit backward span and operation span. The measures of working memory capacity accounted for 24.7% of the variability in phone identification score. Conclusion: Identification of phones in the absence of contextual cues increases the cognitive load. Therefore, higher working memory capacity might aid in native phone identification in difficult situations. This study reveals the top down influence of cognition on native speech perception.

      • KCI등재

        Chemically Modified Submicron Silica Particulate Extractants for Preconcentration of Mercury(II)

        Usha Gupta,Anupreet Kaur 대한화학회 2008 Bulletin of the Korean Chemical Society Vol.29 No.10

        A new analytical method using 1-(2-pyridylazo)-2-naphthol modified SiO2 nanoparticles as solid-phase extractant has been developed for the preconcentration of trace amounts of mercury(II) in different water samples. Conditions of the analysis such as preconcentration time, effect of pH, sample volumes, shaking time, elution conditions and effects of interfering ions for the recovery of analyte were investigated. The adsorption capacity of nanometer SiO2-PAN was found to be 260 μmolg−1 at optimum pH and the detection limit (3σ) was 0.48 μgL−1. The extractant showed rapid kinetic sorption. The adsorption equilibrium of mercury(II) on nanometer SiO2-PAN was achieved just in 5 mins. Adsorbed mercury(II) was easily eluted with 5 mL of 6 M hydrochloric acid. The maximum preconcentration factor was 50. The method was applied for the determination of trace amounts of mercury(II) in various water samples and industrial effluents.

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