Effect of High Myopia on Optic Nerve Head by Confocal Scanning Laser Ophthalmoscopy in Nepalese Eyes

Gauri Shankar Shrestha,Sagun Narayan Joshi,Madhu Thapa,ananda kumar sharma 대한안과학회 2019 Korean Journal of Ophthalmology Vol.33 No.2

Purpose: To compare parameters of confocal scanning laser ophthalmoscopy (Heidelberg Retinal Tomograph[HRT] II) in high myopia with age- and sex-matched emmetropes. Methods: A hospital-based cross-sectional study was conducted among Nepalese subjects aged 18 to 35years at BP Koirala Lions Centre for Ophthalmic Studies, Institute of Medicine, Maharajgunj, Kathmandu fromNovember 2015 to October 2016. Fifty consecutive subjects with high myopia (spherical equivalent rangingfrom -6.00 to -12.00 diopters) and age- and sex-matched emmetropic subjects were enrolled for comparison. Correlations between disc area and other HRT parameters, asymmetry between the right and left eyes, andcomparisons between male and female subjects in both high myopic and emmetropic groups were evaluated. Results: Disc area was not significantly (p = 0.11) larger in high myopic eyes than in emmetropic eyes. HRTparameters in highly myopic eyes involved smaller cup parameters and greater rim parameters comparedwith emmetropic eyes. Disc area was found to be significantly positively correlated with inter disc parametersand significantly negatively correlated with rim to disc area ratio in the high myopia group. Disc area and otherintra-disc parameters showed significant correlations between right and left eyes in both high myopia and emmetropia,and no significant differences between males and females from a Nepalese population. Conclusions: Characteristics of HRT parameters in high myopic eyes involved smaller cup parameters andgreater rim parameters compared with emmetropic eyes in a Nepalese population. The effect of disc area onHRT parameters differed significantly only in height variation contour by emmetropic eyes.

엽록체 DNA 염기서열에 근거한 물여뀌 종집단(마디풀과)의 분류학적 연구

Gao Yaqian,Gauri Shankar Bhandari,박진희,박종욱 한국식물분류학회 2013 식물 분류학회지 Vol.43 No.1

마디풀과의 물여뀌 종집단(Polygonum amphibium L. complex)은 육상 및 수중 환경 모두에 서식할 수 있는 분류군으로, 서식 환경에 따라 다양한 형태 변이를 나타내어 현재까지 많은 분류군들이 기재되어 왔다. 아시아 및 북미산 107개체로부터 측정한 11개 형태형질을 사용하여 주성분분석을 수행한 결과, 본 종집단에서 존재하는 수생형 및 육생형 개체들은 모든 지역집단에서 잎의 형태 및 크기, 엽병의 길이 등에 의해 서로 구분되는 것으로 나타났다. 그러나, 동일 개체군 또는 동일 지역내에서 채집된 수생형과 육생형 개체들은 엽록체 DNA 4개 구간(matK, psbA-trnH IGS, rbcL-accD IGS, trnL-trnF)에서 완전히 동일한 염기서열을 공유하는 것으로 밝혀져 유전적으로는 분기되지 않은 것으로 추정되며, 따라서 본 종집단에서 나타나는 생육형간의 형태적 차이는 서식지 환경에 따른 개체 변이인 것으로 판단된다. 형태분석 및 엽록체 4구간 염기서열 유합자료의 계통분석 결과, 한국, 일본, 중국, 몽골, 극동 러시아 지역 등에 분포하는 아시아산 개체들은 북미지역집단 개체들 및 유럽의 영국산 개체와 형태적, 유전적으로 뚜렷이 구분되는 것으로 밝혀졌으며, 따라서 한반도산 개체들을 포함하는 아시아 지역집단 개체들은 P. amphibium의 하나의 변종(P. amphibium var. amurense Korsh.)으로 인식하는 것이 타당한 것으로 판단된다. The Polygonum amphibium complex (Poygonaceae) is a highly polymorphic taxon that can grow in aquatic environments as well as in moist terrestrial habitats. Aquatic and terrestrial plants of the P. amphibium complex vary significantly in morphology and exhibit very complicated patterns of morphological variation, resulting in the description of numerous infra-specific taxa. Principal components analysis of 107 individuals of the P. amphibium complex from Asia and North America using 11 morphological characters showed that the aquatic plants can be discerned from the terrestrial plants by leaf size, shape, and petiole length. In contrast, both aquatic and terrestrial plants collected from the same population or locality shared identical sequences in the matK, psbA-trnH IGS, rbcL-accD IGS and trnL-trnF regions of the chloroplast DNA (cpDNA), suggesting that aquatic and terrestrial forms of the P. amphibium complex are not genetically diverged; morphological differences between the two forms are probably due to the differences in environmental conditions of the habitats. In addition, results from the morphological analysis and the maximum parsimony analysis of the cpDNA data set revealed that the plants from Asia including Korea, Japan, China, Mongolia and Russia Far East are diverged from those in North America and Europe, suggesting that the Asian populations should be recognized as a distinct variety, P. amphibium var. amurense Korsh.

Investigations on Split-Source Inverter Based Shunt Active Power Filter Integrated Microgrid System for Improvement of Power Quality Issues

Barik Prasanta Kumar,Shankar Gauri,Sahoo Pradeepta Kumar 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.4

To meet the constantly rising energy demand, renewable energy sources are increasingly being used in power networks, transforming the traditional power distribution system into a microgrid (MG) based system. Simultaneously, the presence of nonlinear loads in the MG system may cause unwanted power quality (PQ) issues, which must be thoroughly addressed. The use of a shunt active power fi lter (SAPF) to mitigate PQ problems in a standalone MG system is discussed in this paper. SAPF performance must meet a number of requirements, including constant dc-link capacitor voltage, continuous input current fl ow, and lower switching loss, all of which are diffi cult to achieve with a traditional voltage source inverter (VSI). A new inverter named split source inverter (SSI) has been recently developed and has all the above features. In SSI, both the dc and ac sides are regulated using modulation index with the same control mechanism as that of normal VSI. The application of SSI with SAPF is yet to be explored in detail. As a result, a performance comparison of two inverters (traditional VSI and SSI) based SAPF with modifi ed synchronous reference frame technique for generation of reference current, adaptive hysteresis current controller for generation of switching pulse, and proportional-integral controller or fuzzy logic controller for dc-link voltage regulation has been investigated in this paper. Under ideal/non-ideal source conditions, the proposed SAPF outperforms other counterparts in terms of dc-link voltage regulation and mitigation of harmonics generated by various nonlinear loads.

Altering Conidial Dispersal of Alternaria solani by Modifying Microclimate in Tomato Crop Canopy

Prashant Prakash Jambhulkar,Nitiprasad Jambhulkar,Madanlal Meghwal,Gauri Shankar Ameta 한국식물병리학회 2016 Plant Pathology Journal Vol.32 No.6

Early blight of tomato caused by Alternaria solani, isresponsible for severe yield losses in tomato. The conidiasurvive on soil surface and old dry lower leavesof the plant and spread when suitable climatic conditionsare available. Macroclimatic study reveals thathighest inoculum concentration of Alternaria sporesappeared in May 2012 to 2013 and lowest concentrationduring January 2012 to 2013. High night temperaturepositively correlated and significantly (P <0.01) involved in conidial spore dispersal and low relativehumidity (RH) displayed significant (P < 0.05)but negative correlation with conidial dispersal. Theobjective of the study was to modify microclimaticconditions of tomato crop canopy which may hamperconidial dispersal and reduce disease severity. Weevaluated effect of marigold intercropping and plasticmulching singly and in consortia on A. solani conidialdensity, tomato leaf damage and microclimatic parametersas compar to tomato alone (T). Tomato-marigoldintercropping–plastic mulching treatment (T + M +P) showed 35–39% reduction in disease intensity ascompared to tomato alone. When intercropped withtomato, marigold served as barrier to conidial movementand plastic mulching prevented evapotranspirationand reduced the canopy RH that resulted in lessgermination of A. solani spores. Marigold intercroppingand plastic mulching served successfully as physicalbarrier against conidial dissemination to diminishsignificantly the tomato foliar damage produced by A. solani.

Optimizing Fibre Optics for Coal Mine Automation

Atul Kumar,Dheeraj Kumar,U. K. Singh,P. S. Gupta,Gauri Shankar 보안공학연구지원센터(IJCA) 2011 International Journal of Control and Automation Vol.4 No.2

Altering Conidial Dispersal of Alternaria solani by Modifying Microclimate in Tomato Crop Canopy

Jambhulkar, Prashant Prakash,Jambhulkar, Nitiprasad,Meghwal, Madanlal,Ameta, Gauri Shankar The Korean Society of Plant Pathology 2016 Plant Pathology Journal Vol.32 No.6

Early blight of tomato caused by Alternaria solani, is responsible for severe yield losses in tomato. The conidia survive on soil surface and old dry lower leaves of the plant and spread when suitable climatic conditions are available. Macroclimatic study reveals that highest inoculum concentration of Alternaria spores appeared in May 2012 to 2013 and lowest concentration during January 2012 to 2013. High night temperature positively correlated and significantly (P < 0.01) involved in conidial spore dispersal and low relative humidity (RH) displayed significant (P < 0.05) but negative correlation with conidial dispersal. The objective of the study was to modify microclimatic conditions of tomato crop canopy which may hamper conidial dispersal and reduce disease severity. We evaluated effect of marigold intercropping and plastic mulching singly and in consortia on A. solani conidial density, tomato leaf damage and microclimatic parameters as compar to tomato alone (T). Tomato-marigold intercropping-plastic mulching treatment (T + M + P) showed 35-39% reduction in disease intensity as compared to tomato alone. When intercropped with tomato, marigold served as barrier to conidial movement and plastic mulching prevented evapotranspiration and reduced the canopy RH that resulted in less germination of A. solani spores. Marigold intercropping and plastic mulching served successfully as physical barrier against conidial dissemination to diminish significantly the tomato foliar damage produced by A. solani.

Effect of sorbitan monostearate concentration on the thermal, mechanical and drug release properties of oleogels

Arfat Anis,Kunal Pal,Sai Sateesh Sagiri,Uvanesh Kasiviswanathan,Gauri Shankar Shaw,Meenakshi Singh 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.5

The current study describes the effect of the concentration of Span 60 (gelator) on the properties of oleogels. Mustard oil was chosen as the representative vegetable oil. Microscopy showed that an increase in the gelator concentration resulted in the increase in the gelator network density. Thermal studies (crystallization kinetics and differential scanning calorimetry) indicated a 2-stage crystallization process. An increase in the gelator proportion resulted in the increase in the compatibility amongst the oleogel components. The formation of gelator network was governed by the interaction amongst the hydroxyl groups of Span 60. A variation in the gelator proportion resulted in the alteration in the d-spacing, crystallite size and lattice strain. The variation in the above-mentioned properties was found to affect the viscoelastic properties of the oleogels as was predicted from the Weichert model. The drug release studies suggested that the drug diffusion due to the gelator network relaxation during drug release was predominant as compared to the Fickian diffusion. The results suggested that it is possible to alter not only the release profile of drugs but also the physical properties (of the oleogels) by tailoring the gelator concentration.