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501.
Prafulla Kumar Behera 《Resonance》2013,18(3):248-263
The Large Hadron Collider (LHC) at CERN — the most expensive and complex instrument mankind has ever built to address some of the most fundamental questions of Nature — is colliding proton-on-proton at high energy since November 2009. The full data set delivered by the LHC over the last 4 years has been analyzed by the ATLAS and CMS experiments in their pursuit of the Higgs boson, the particle responsible for generating masses for the basic building blocks of matter. In this article I discuss in detail the building and commissioning of the detector, search strategy and results obtained by the two experiments with special emphasis on ATLAS. 相似文献
502.
The need to continuously evaluate resource usage, whether in print or online, has been a challenge for libraries for a long time. The shift in resources to digital formats has made gauging the utility of resources more convenient as well as enabling cross database comparisons on various parameters. In this context, the article explores the aggregator databases subscribed by Indian Institute of Management Ahmedabad library. The study compares EBSCO's Business Source Complete, EBSCO's Academic Search Premier, Proquest's ABI INFORM Complete, JSTOR, and Project Muse packages in terms of the features available, usage, and the most used journals in these packages. 相似文献
503.
Indranath Ghosh Debojyoti Bhattacharjee Anjan Kumar Das Goutam Chakrabarti Anindya Dasgupta Subir Kumar Dey 《Indian journal of clinical biochemistry : IJCB》2013,28(1):24-29
The aim of this study was to assess the diagnostic yield of the tumour markers carcinoembryonic antigen, carbohydrate antigen 15-3, carbohydrate antigen 19-9 and carbohydrate antigen 125, in serum and bronchoalveolar lavage fluid in a group of patients with bronchogenic carcinoma. Serum and bronchoalveolar lavage fluid samples were collected in a group of 90 patients with benign or malignant pulmonary diseases. After appropriate processing, tumour markers were determined by enzyme immunoassay. The diagnostic yields (sensitivity, specificity and predictive values) in each environment (serum and bronchoalveolar lavage fluid) were obtained by using "Receivers operating characteristic" curve. Determined individually, carcinoembryonic antigen, carbohydrate antigen 19-9 and carbohydrate antigen 125, showed the greatest diagnostic accuracy in bronchoalveolar lavage fluid. Carbohydrate antigen 15-3 did so in serum. Carcinoembryonic antigen was the most relevant marker in bronchoalveolar lavage fluid. For the factors evaluated in this study, determination of carcinoembryonic antigen, carbohydrate antigen 19-9 and carbohydrate antigen 125 in bronchoalveolar lavage fluid were clinically more useful markers in comparison with serum, although the latter may also be helpful in certain situations. Although there is no specific tumour marker for lung cancer, the combination of several can be used to diagnose most patients with lung cancer and also to rule out false positive and negative cases. 相似文献
504.
Narotam Sharma Veena Sharma Prem Raj Singh Shivani Sailwal Rajeev S. Kushwaha Rajesh K. Singh Satish C. Nautiyal Pankaj Mishra Tariq Masood R. K. Singh 《Indian journal of clinical biochemistry : IJCB》2013,28(3):305-308
Genitourinary tuberculosis is a disease of the genitourinary system which includes the entire urinary tract and reproductive system. Genital tuberculosis is an important cause of female infertility, especially in developing nations like India. In the present study, a total of 257 clinical specimens comprising of endometrial biopsy (109), endometrial curetting (42), menstrual blood (8), semen (17), placenta (11) and urine (70) were collected from patients and subjected for PCR, Culture and AFB detection. The endometrial biopsy, endometrial curetting, menstrual blood, semen, placenta, urine showed 30.2, 45.2,12.5, 5.8, 27.2, 31.4 %, positivity rate for tuberculosis by PCR, 7.3, 9.5, 25.0, 0, 9, 8.5 % by culture and 1.8, 2.3, 0, 0, 0, 2.8 % respectively by AFB smear. Being a novel, rapid technique, PCR is the method of choice for rapid diagnosis and management of genitourinary tuberculosis shared with the other concerned tests. This study reveals that genital tuberculosis can occur in any age group, however, the majority of patients were from reproductive age (nearly 75 % of them were from 20–45 years of age) group. 相似文献
505.
Hafedh Al-Shihi Sujeet Kumar Sharma Mohamed Sarrab 《Education and Information Technologies》2018,23(5):1805-1824
The proliferation of mobile computing technologies is playing major role in the growth of mobile learning (M-learning) market around the globe. The purpose of this paper is to develop a research model in the lines of commonly used models the Unified Theory of Acceptance and Use of Technology (UTAUT) and Technology Acceptance Model (TAM) by incorporating constructs namely flexibility learning, social learning, efficiency learning, enjoyment learning, suitability learning, and economic learning that can predict M-learning adoption in a developing country. The data were collected from 388 students from all major universities/colleges in the capital city (Muscat) of Oman. The neural network modeling was employed to predict M-learning adoption. The neural network modeling results showed that flexibility learning, social learning, efficiency learning, enjoyment learning, suitability learning, and economic learning variables have significant influence on the intention of students to accept mobile learning. The key outcomes of this study suggest important determinants that can assist academic administrators and telecommunication service providers to enhance the adoption of M-learning with the help of suitable strategy. 相似文献
506.
Ratan Kumar D. P. Chattopadhyay Radhey Shyam 《Indian journal of clinical biochemistry : IJCB》1993,8(1):20-25
Intraperitoneal administration of glucose (20%), Sucrose (20%) and mannitol (15%) to the rats, at a dose of 5ml/100g body weight 3 hrs. prior to hypoxic exposure (simulated high altitude 10,973m, 32°C) significantly increased the hypoxic tolerance. Intraperitoneal administration of these solutions resulted in accumulation of transudate fluid in the peritoneal cavity. A decrease in the excretion of urine, increase in hematocrit value, haemoglobin level, blood viscosity and serum protein were observed. Moisture content of lungs amongst other tissue was found to be decreased. Results are suggestive that dialysis across the peritoneal membrane might have removed some material from the blood in the peritoneal fluid which might have been responsible for the increased hypoxic tolerance. 相似文献
507.
Debye won the 1936 Nobel Prize in Chemistry for his contributions to molecular structure, dipole moment relationship and for
diffraction of X-rays and electrons. Electrochemists, however, remember him for the Debye-Hückel limiting law that describes
the behavior of strong electrolytes. In explaining the non-ideal behavior of strong electrolytes, his mathematical treatment
assumes that each ion is surrounded by an ionic cloud of oppositely charged ions, which retards the movement of ions in the
medium. The theory not only provides a method for calculation of activity coefficients, but has also helped, among other things,
in our understanding of diffusion in ionic media, change in the rate of ionic reactions upon addition of salts, and biochemical
reactions. 相似文献
508.
The 2010 Nobel Prize in Chemistry was awarded to three scientists, R F Heck, E-I Negishi and A Suzuki, for their work on “Palladium
— Catalyzed Cross Couplings in Organic Synthesis”. It pertains to research done over a period of four decades. The synthetic
procedures embodied in their work enable construction of C-C bond selectively between complex molecules as in simple ones
at desired positions without disturbing any functional groups at other parts of the reacting molecules. The work finds wide
applications in the synthesis of pharmaceuticals, agricultural chemicals, and molecules for electronics and other applications.
It would not have been possible to synthesize some of the complex natural products or synthetic compounds without using these
coupling reactions in one ormore steps. 相似文献
509.
Kumar Laxman 《Instructional Science》2011,39(6):881-900
Solving real-world problems is an effective learning activity that promotes meaningful learning in formal educational settings.
Problems can be classified as being either well structured or ill structured. Internet information search approaches have
an influential role to play in the successful performance of problem solving. A better understanding of how students differentially
model information search strategies and movements in tackling well- and ill-structured problems is essential for creating
engaging problem-solving environments for students. Static measures, such as the number of accessed nodes or links, or the
number of times particular web browser function buttons are clicked, are limited in their ability to analyze attributes of
information search patterns. A more dynamic and spatial representation of web movements and navigational patterns can be realized
through the use of navigational paths as data. The two path-specific structural metrics that can be used to assess network-based
navigational paths in relation to the structuredness of the problem-solving task are compactness and stratum. These metrics are, respectively, the indicators of the connectedness and linearity of network-based structures defining students’ online navigational visitations during the problem-solving sessions. This
study explored the relevance and utility of these two metrics in analyzing the navigational movements of learners in seeking
out electronic information to accomplish successful problem solving. The outcome findings of this study show that well- and
ill-structured problems demand different cognitive and information seeking navigational approaches. The differing values of
the two path metrics in analyzing the search movements organized by students in attending to well- and ill-structured problems
were a direct result of the contrasting patterns of navigational path movements. The search patterns associated with well-structured
problem solving tended to be more linear and less connected, whereas those related to ill-structured problem solving were
more distributed and inter-connected. 相似文献
510.
Post-secondary educational attainment is an increasingly important prerequisite to many valued outcomes. This paper examines the association of racially-specific high school course of study with student’s postsecondary educational attainment using ELS 2002–2012 and a comprehensive measure of course intensity derived from students’ patterns of course-taking. Results support a partial presence of racially-specific association of high school course of study. We also find that only Asian-American and American Indian/Alaskan Native students in the middle course intensity and Asian-American students in high course intensity ranges are more likely to obtain at least a 4-year college degree than same-race students in the low course intensity group. However, the same pattern is not evident for White, African-American, multi-racial, and Hispanic students, indicating that they do not experience the same benefit from academically rigorous courses of study. Also, educational expectations do not mediate the relationships among race, course of study, and postsecondary educational trajectory differently for students of different racial groups, i.e., they do not play a larger role in mediating the relationship between course of study and postsecondary educational trajectory for White students. 相似文献