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1.
The objectives and stages of operating systems introduced in Part 1 are continued here. Four major components —process management, input-output (I/O) device management, memory management, file management and protection are discussed.  相似文献   
2.
Emil Fischer is considered to be the founding father of the field of peptide chemistry and originator of the term peptide. In the beginning of the 20th century, Fischer had a clear vision to foresee the day when a protein would be synthesized. Subsequent to this brilliant beginning, progress however was slow for the next 50 years. In 1953, the chemical synthesis of oxytocin by duVigneaud was a landmark achievement. The subsequent decades witnessed the discovery of a vast number of biologically active peptides. The last two decades of the 20th century was filled with hopes of multiple simultaneous synthesis, peptide libraries and peptide vaccines. This article is a concise account of the types of family of peptides discovered and their biological role.  相似文献   
3.
In this article we examine the objectives and functions ofoperating systems, and then we trace the evolution of operating systems from the first manual system to the current multiprogrammed and time-shared systems.  相似文献   
4.
Biotechnology has opened unprecedented avenues for exploring biological systems. One of the key techniques in genetic engineering is gene transfer, which involves transfer of recombinant DNA into plant cells to generate transgenic plants. Genes and genomes from a wide range of organisms are being manipulated for the benefit of mankind. Application of genetic engineering in agriculture has produced significant achievements such as yield improvement of major food crops.  相似文献   
5.
Ayurveda is a traditional form of medicine used by majority of the Indians. Here we report three cases of lead toxicity, following intake of Ayurvedic medicines. Three patients presented with blood lead levels (BLLs) of 122.4, 115 and 42.8 μg/dl respectively at the time of hospitalization. The first case was chelated with D- penicillamine, the second with calcium disodium ethylene diamino tetra acetate (EDTA) and the third with environmental intervention and education. Associated Ayurvedic products were collected from patients and analyzed for metallic concentration. Cessation of Ayurvedic medication along with chelation, nutritional intervention and education, reduced the BLL to 27.4 μg/dl in the first case after 1 year, 21.1 μg/dl after 9 months in the second and 18.2 μg/dl after 6 months in the third case.  相似文献   
6.
Mortality and morbidity attributed to asthma remains to be the biggest nightmare worldwide. Hence, the study was aimed to compare the cardio metabolic risk factors as assessed by Body mass index (BMI), waist hip ratio (WHR), serum triacylglycerol and uric acid in well controlled and poorly controlled asthmatics and to correlate these parameters with the severity of asthma. A case control study was conducted on 90 subjects who were segregated into well controlled asthmatics (n = 30) and poorly controlled asthmatics (n = 30) who were diagnosed based on Global initiative for Asthma management guidelines and healthy volunteers (n = 30). Centrifuged fasting venous blood samples were used for biochemical analysis, pulmonary function test, BMI, and waist hip ratio (WHR) were measured. The statistical analysis was done using SPSS version 17. There was a significant increase in BMI, WHR, lipid profile, serum uric acid and decrease in forced expiratory volume (FEV1), forced vital capacity (FVC), and FEV1/FVC in poorly controlled asthmatics. There was a significant association between FEV1 and serum uric acid, BMI and Triacylgycerol in poorly controlled asthmatics. Poorly controlled asthmatics have greater risk of developing cardiometabolic problems. Serum uric acid can be used as one of the severity markers in asthma to assess cardio metabolic risk.  相似文献   
7.
Drought,flood,salinity,or a combination of these limits rice production.Several rice varieties are well known for their tolerance to specific abiotic stresses.We determined genetic relationship among 12 rice varieties including 9 tolerant to drought,flood,or salinity using inter-simple sequence repeat (ISSR) markers.Based on all markers,the nine tolerant varieties formed one cluster distinct from the cluster of three control varieties.The salt-tolerant varieties were closest to two flood-tolerant varieties,and together they were distinct from the drought-tolerant varieties.(GA)8 YG was the most informative primer,showing the highest polymorphic information content (PIC) and resolving power (Rp).The drought-,flood-,and salt-tolerant varieties grouped in three distinct clusters within the group of tolerant varieties,when (GA)8 YG was used.Sabita was the only exception.The two aus varieties,Nagina22 and FR13A,were separated and grouped with the drought-and flood-tolerant varieties,respectively,but they were together in dendrograms based on other primers.The results show that ISSR markers associated with (GA)8 YG delineated the three groups of stress-tolerant varieties from each other and can be used to identify genes/new alleles associated with the three abiotic stresses in rice germplasm.  相似文献   
8.
An important research area in education and technology is how the learners use e-learning. By exploring the various factors and relationships between them, we can get an insight into the learners’ behaviors for delivering tailored e-content required by them. Although many tools exist to record detailed navigational activities, they don’t explore the learners’ usage patterns for an adaptive e-learning site. The previous web log data analyses, done so far, have been very limited in their scope as they lack detailed empirical results on the learning technology usage. This paper discusses the detailed results of a case study of web data mining in a specific e-learning application. The main objective of this study is to conduct research on usability and effectiveness of the e-content by analyzing the web log. For this, a suitable data set was retrieved from raw web log records, to which various web mining & statistical techniques could be applied. We have evaluated different features of e-content that can lead to better learning outcomes for the learners, by understanding their navigational behaviors, their interaction with system and their area of interest. We found, for example, what sequence of topics were the most liked and the least liked by the learners; we also found that these patterns, lead us to hypothesize, the correlation and regression analysis between the average time, test score and total attempts.  相似文献   
9.
Awareness about the toxic effects of non-essential metals is still lacking in developing countries. Lead is one among them, which ranks second in the Agency for Toxic Substances and Disease Registry’ s top 20 lists of toxic metals. Some of the herbal medicines prepared from certain roots and leaves are known to contain this toxic metal at alarming levels. We have a case of a person who suffered from the toxic effects of lead such as vomiting and colicky abdominal pain after consuming a herbal remedy for Jaundice treatment. This went unrecognized initially because of the presence of multiple problems like Malaria and Renal calculi. Lead poisoning as causative factor for anemia, vomiting and colic were confirmed only when blood lead concentration was estimated. A combination of chelation therapy and nutritional supplementation was found to be useful in reducing the body lead burden.  相似文献   
10.
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