295 research outputs found
Clinico mycological study of dermatophytosis
Background: Dermatophytoses is common, more prevalent in tropical and subtropical countries including India. Though not life threatening as it can cause great discomfort particularly in immunosuppressive conditions. It remains a general public health problem, which is prevalent in all age groups and both sexes. Aims: To study clinicomycological profile of patients.Methods: The Cross Sectional study was done on clinically diagnosed cases of Dermatophytosis with sample size of 200 cases for one and half year period.Results: The males to female ratio are 1.86:1. The common age group affected was 31-40years. Dermatophytosis was common in active workers, more common in urban than rural population particularly in low socioeconomic group of people and in summer season. Tinea corporis was the common clinical variant. 133 cases were both KOH and culture positive. The KOH mount was positive in 90% cases. In the present study 144 patients (72%) had positive culture results and 47 cases were KOH positive but culture negative, 11 cases were culture positive but KOH negative and 9 cases were both KOH and culture negative. Microsporum audoinii was isolated in 2%, Trichophyton mentagrophytes in 14%, Trichophyton rubrum in 52% and Trichophyton violaceum in 4%.Conclusions: Tinea corporis and Tinea cruris were the most common clinical types. Tinea corporis was predominantly a disease of adult males whereas Tinea capitis was seen mainly in pre- pubertal age group. Potassium hydroxide (KOH) wet mount and cultures were done for all the cases. T. rubrum was the commonest species isolated from most clinical types followed by T. mentagrophytes except T. capitis where T. violaceum was isolated
Unique Observations of a Geomagnetic SI^+ -- SI^- Pair: Solar Sources and Associated Solar Wind Fluctuations
The paper describes the occurrence of a pair of oppositely directed sudden
impulses (SI), in the geomagnetic field (X), at ground stations, called
SI -- SI pairs, that occurred between 1835 UT and 2300 UT on 23
April 1998. The SI -- SI pair, was closely correlated with
corresponding variations in the solar wind density, while solar wind velocity
and the southward component of the interplanetary magnetic field (Bz) did not
show any correspondence. Further, this event had no source on the visible solar
disk. However, a rear-side partial halo coronal mass ejection (CME) and an M1.4
class solar flare behind the west limb, took place on 20 April 1998, the date
corresponding to the traceback location of the solar wind flows. This event
presents empirical evidence, which to our knowledge, is the best convincing
evidence for the association of specific solar events to the observations of an
SI -- SI pair. In addition, it shows that it is possible for a
rear side solar flare to propagate a shock towards the earth.Comment: The paper has just been accepted in the Journal of Geophysical
Research (Space Physics) on 20 September 2010. It is 17 pages with 4 figure
Single phase transformerless inverter for grid connected photovoltaic system with reduced leakage current
Introduction. Transformerless inverters are of vital importance in the field of grid connected solar photovoltaic systems offering higher efficiency than the conventional one. i.e., using transformer. General grid connected inverters are constituting of transformers requires more area besides the loss in them. Problem. Eliminating transformers can cause leakage current due to the variation of common mode voltage which in turn due to parasitic capacitance effect. Research literature in transformerless inverters has addressed the problems of common mode leakage current issues by offering the study of different inverter topologies like H4, H5, H6 and HERIC etc. utilizing variety of modulation strategies like unipolar, bipolar pulse width modulations. Goal. The paper significantly presents a new transformerless inverter topology, analyzes common mode voltage and leakage current behavior of the system. The simulation is carried out for comparing the leakage current profiles with other transformerless inverter topologies in literature. Novelty. This paper gives an impression of the efficient transformerless inverter for grid connected photovoltaic system. Results. The various inverter topologies full bridge with different pulse width modulation techniques are analyzed and to determine the common mode voltages and leakage currents.Вступ. Безтрансформаторні інвертори мають життєво важливе значення в області сонячних фотоелектричних систем, підключених до мережі, та забезпечують більш високу ефективність, ніж звичайні, завдяки трансформатору. Підключені до загальної мережі інвертори, які складаються з трансформаторів, потребують більшої площі через втрати у них. Проблема. Усунення трансформаторів може спричинити струм витоку через зміну синфазної напруги через вплив паразитної ємності. Дослідницька література з безтрансформаторних інверторів присвячена проблемам синфазних струмів витоку, пропонуючи дослідження різних топологій інверторів, таких як H4, H5, H6, HERIC та ін., з використанням різних стратегій модуляції, таких як уніполярна, біполярна широтно-імпульсна. Мета. У статті докладно подано нову топологію безтрансформаторного інвертора, проаналізовано поведінку синфазної напруги та струму витоку в системі. Моделювання проводиться для порівняння профілів струму витоку з іншими топологіями безтрансформаторних інверторів, описаних у літературі. Новизна. Ця стаття містить ефективний безтрансформаторний інвертор для фотоелектричної системи, підключеної до мережі. Результати. Проаналізовано різні топології інверторів з повним мостом та різними методами широтно-імпульсної модуляції, а також визначено синфазну напругу та струми витоку
A Novel Approach for Extraction of Design Features Using DXF Files
Feature recognition is the key linking element between CAD and CAPP. Different CAD/geometricmodeling packages store the design related information in their own databases. Structures of thesedatabases are different from each other. Automatic Feature Recognition (AFR) is the process ofextracting such feature data for use in the other stages of product life cycle viz., process planning,CNC code generation and inspection etc. This paper presents different algorithms to extract thedesign data stored in the form of Data Exchange Format (DXF) files and to store such data in anorderly form. . A software program is developed in ‘C++’, for extraction of the features (entity)data from the DXF file. The flow chart of the program is given as an appendix. The paperdemonstrates the working of the algorithms using a set of examples
Multiple exposures to swine barn air induce lung inflammation and airway hyper-responsiveness
BACKGROUND: Swine farmers repeatedly exposed to the barn air suffer from respiratory diseases. However the mechanisms of lung dysfunction following repeated exposures to the barn air are still largely unknown. Therefore, we tested a hypothesis in a rat model that multiple interrupted exposures to the barn air will cause chronic lung inflammation and decline in lung function. METHODS: Rats were exposed either to swine barn (8 hours/day for either one or five or 20 days) or ambient air. After the exposure periods, airway hyper-responsiveness (AHR) to methacholine (Mch) was measured and rats were euthanized to collect bronchoalveolar lavage fluid (BALF), blood and lung tissues. Barn air was sampled to determine endotoxin levels and microbial load. RESULTS: The air in the barn used in this study had a very high concentration of endotoxin (15361.75 ± 7712.16 EU/m(3)). Rats exposed to barn air for one and five days showed increase in AHR compared to the 20-day exposed and controls. Lungs from the exposed groups were inflamed as indicated by recruitment of neutrophils in all three exposed groups and eosinophils and an increase in numbers of airway epithelial goblet cells in 5- and 20-day exposure groups. Rats exposed to the barn air for one day or 20 days had more total leukocytes in the BALF and 20-day exposed rats had more airway epithelial goblet cells compared to the controls and those subjected to 1 and 5 exposures (P < 0.05). Bronchus-associated lymphoid tissue (BALT) in the lungs of rats exposed for 20 days contained germinal centers and mitotic cells suggesting activation. There were no differences in the airway smooth muscle cell volume or septal macrophage recruitment among the groups. CONCLUSION: We conclude that multiple exposures to endotoxin-containing swine barn air induce AHR, increase in mucus-containing airway epithelial cells and lung inflammation. The data also show that prolonged multiple exposures may also induce adaptation in AHR response in the exposed subjects
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