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1.
Phoolan Prasad 《Resonance》1997,2(7):8-19
In part 1 of this series we explained the concept of genuine nonlinearity, which is responsible for the appearance of discontinuities in a solution which was initially smooth. To include discontinuities in the solution, it became necessary to consider the governing equation in the form of a conservation law. In this part we first discuss an example of a continuous solution satisfying discontinuous initial data. Then we use the stability consideration to fix a unique solution of the conservation law. In the end, we present three examples which show that genuine nonlinearity significantly changes the evolution of the shape of a pulse. Continuous Solution with Discontinuous Initial Data 相似文献
2.
Hari Prasad 《Resonance》2002,7(12):48-64
Berzelius, the Swedish chemist in 1807 introduced the term ‘organic compounds’ as those substances derived from once living
organisms (organized systems). Carbon exhibits the property of catenation (formation of chains) and forms a plethora of compounds
on earth. Silicon on the other hand which is placed below carbon in the periodic table does not exhibit this property. This
article is a brief account of some of the several reagents and classes of compounds encountered in organosilicon chemistry. 相似文献
3.
Emmanouil Amolochitis Ioannis T. Christou Zheng-Hua Tan Ramjee Prasad 《Information processing & management》2013
We present PubSearch, a hybrid heuristic scheme for re-ranking academic papers retrieved from standard digital libraries such as the ACM Portal. The scheme is based on the hierarchical combination of a custom implementation of the term frequency heuristic, a time-depreciated citation score and a graph-theoretic computed score that relates the paper’s index terms with each other. We designed and developed a meta-search engine that submits user queries to standard digital repositories of academic publications and re-ranks the repository results using the hierarchical heuristic scheme. We evaluate our proposed re-ranking scheme via user feedback against the results of ACM Portal on a total of 58 different user queries specified from 15 different users. The results show that our proposed scheme significantly outperforms ACM Portal in terms of retrieval precision as measured by most common metrics in Information Retrieval including Normalized Discounted Cumulative Gain (NDCG), Expected Reciprocal Rank (ERR) as well as a newly introduced lexicographic rule (LEX) of ranking search results. In particular, PubSearch outperforms ACM Portal by more than 77% in terms of ERR, by more than 11% in terms of NDCG, and by more than 907.5% in terms of LEX. We also re-rank the top-10 results of a subset of the original 58 user queries produced by Google Scholar, Microsoft Academic Search, and ArnetMiner; the results show that PubSearch compares very well against these search engines as well. The proposed scheme can be easily plugged in any existing search engine for retrieval of academic publications. 相似文献
4.
In previous studies, we have reported first in vivo evidence of copper deposition in the choroid plexus, cognitive impairments, astrocytes swelling (Alzheimer type II cells) and astrogliosis (increase in number of astrocytes), and degenerated neurons coupled with significant increase in the hippocampus copper and zinc content in copper-intoxicated Wistar rats. Nonetheless, hippocampus iron levels were not affected by chronic copper-intoxication. Notwithstanding information on distribution of copper, zinc and iron status in different regions of brain due to chronic copper exposure remains fragmentary. In continuation with our previous study, the aim of this study was to investigate the effects of intraperitoneally injected copper lactate (0.15 mg Cu/100 g body weight) daily for 90 days on copper, zinc and iron levels in different regions of the brain using atomic absorption spectrophotometry. Copper-intoxicated group showed significantly increased cortex, cerebellum and striatum copper content (76, 46.8 and 80.7 % increase, respectively) compared to control group. However, non-significant changes were observed for the zinc and iron content in cortex, cerebellum and striatum due to chronic copper exposure. In conclusion, the current study demonstrates that chronic copper toxicity causes differential copper buildup in cortex, cerebellum and striatum region of central nervous system of male Wistar rats; signifying the critical requirement to discretely evaluate the effect of copper neurotoxicity in different brain regions, and ensuing neuropathological and cognitive dysfunctions. 相似文献
5.
Debi de Prasad C. R. Maity de Swapan 《Indian journal of clinical biochemistry : IJCB》1993,8(1):71-72
Urinary excretion of 3 methoxy-4-hydroxy phenyl glycol (MHPG) and 3-methoxy-4-hydroxy mandelic acid (VMA) were estimated in 18 Post-Japanese Encephalitis depressive patients and 20 unipolar depressive patients to determine their biochemical differences. Both the metabolites were low in the former group in comparison to the later group, indicating that the metabolic events in respect to catecholamine turn over are different in two disorders. 相似文献
6.
Prasad P. Torkadi I. C. Apte A. K. Bhute 《Indian journal of clinical biochemistry : IJCB》2014,29(1):79-83
Alcoholic liver disease (ALD) is due to excessive alcohol intake for long duration. Distinguishing ALD from non-ALD (non-alcoholic steatohepatitis, hepatitis of viral origin) is difficult as patient may deny alcohol abuse. Clinical examination, histology and serology may not differentiate these conditions. Accurate diagnosis is important as management of ALD differs from non-ALD patients. The aim of our study was (1) To evaluate the patients of ALD and non-ALD by biochemical parameters compared to controls, (2) To assess whether these parameters can differentiate ALD from non-ALD. Study was carried out on 50 patients of ALD in group I and 35 patients of NASH (non-alcoholic steatohepatitis) and acute viral hepatitis each in group II. Age matched healthy controls n = 50. Selection criteria—history of alcohol intake (amount and duration), clinical examination, sonography of abdomen, serum alanine transaminase (ALT) and bilirubin levels. Blood samples were analyzed for bilirubin, aspartate transaminase (AST), ALT, alkaline phosphatase (ALP), gamma glutamyl transferase (GGT) by kinetic method. Statistical analysis was done by Student unpaired ‘t’ test. Patients of ALD have raised AST/ALT ratio (De Ritis ratio) (>2), ALP and GGT compared to controls (P < 0.01).There is significant difference in AST/ALT ratio, serum GGT and ALP in ALD group compared to that in NASH and acute viral hepatitis (P < 0.05). This study suggests that De Ritis ratio >2 in ALD patients may be due to alcohol induced hepatic mitochondrial injury and pyridoxine deficiency. High GGT and ALP values may indicate enzyme induction by alcohol and mild cholestasis. Thus ALD patients have severe hepatic damage. De Ritis ratio <1 and normal to mild elevation in GGT level in NASH and acute viral hepatitis suggest mild hepatic injury of non-alcoholic origin. Our study concludes that ALD patients can be differentiated from NASH and acute viral hepatitis with certainty by measuring serum AST/ALT ratio, GGT and ALP. These biochemical parameters may help clinicians to support the diagnosis of ALD and non-ALD. 相似文献
7.
Vandana Dixit Ashok V. Kurup A K Gupta O M Kataria G B K S Prasad 《Indian journal of clinical biochemistry : IJCB》1997,12(1):39-43
Lymphatic filariasis caused byWuchereria bancrofti is a major health problem next only to malaria. A study had been conducted to estimate the prevalence of microfilaraemia in a rural endemic community near Raipur. The incidence of microfilaramia in the community was found to be about 14% when studied by night finger prick method. The incidence appears to be more in males as compared to females. The infection rate in vector population i.e.,Culex quinquefasciatus was recorded at a rate of 10%. No relationship could be drawn between the rates of vector and human filarial infections or between the density of vector population and the rate of vector/human infection(s). Prior health education is essential before taking up control and preventive measures in given endemic zone. 相似文献
8.
Kiran?SarvabhotlaEmail author Prasad?Pingali Vasudeva?Varma 《Information Retrieval》2011,14(3):337-353
With the growth of social media, document sentiment classification has become an active area of research in this decade. It
can be viewed as a special case of topical classification applied only to subjective portions of a document (sources of sentiment).
Hence, the key task in document sentiment classification is extracting subjectivity. Existing approaches to extract subjectivity
rely heavily on linguistic resources such as sentiment lexicons and complex supervised patterns based on part-of-speech (POS)
information. This makes the task of subjective feature extraction complex and resource dependent. In this work, we try to
minimize the dependency on linguistic resources in sentiment classification. We propose a simple and statistical methodology
called review summary (RSUMM) and use it in combination with well-known feature selection methods to extract subjectivity.
Our experimental results on a movie review dataset prove the effectiveness of the proposed methodology. 相似文献
9.
10.
G. Prasad 《European Journal of Engineering Education》2010,35(2):187-213
This paper gives an overview of the Indian technical education system with regard to both its quantitative and qualitative scenario and upholds the value of accreditation in quality improvement and quality assurance of educational programmes. The paper presents a comparison of accreditation systems being followed in some important countries, including India, that are signatories or provisional members of Washington Accord. It also looks into the reasons of the sparse level of accreditation work completed by the National Board of Accreditation (NBA) since its inception. While mentioning strengths of the NBA accreditation system, the paper points out some shortcomings in the policy, self-assessment questionnaire, criteria, weightage assigned to criteria and rating scheme followed by NBA. Some important recommendations have also been made to render the accreditation system more effective and acceptable to various stakeholders of the technical education sector in India. 相似文献