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1.
Ravi Mosurkal 《Resonance》2001,6(10):76-86
The dream of generating electricity from sunlight in large scale at low cost may not be that far from reality in this century.
Rapidly emerging solar energy technology using low cost dye sensitized photovoltaic cells on plastics would be a real boost
for the third world countries. Though the conventional silicon solar cells are efficient in converting solar energy into electricity
until now, the non conventional solar cells based on molecular photosensitization by colored materials in wide band gap semiconductors
is a fast growing field of basic scientific and industrial research. Present state-of-the-art cells using molecular dyes shows
energy conversion efficiencies of 10–11%. In this article, we present the concept of dye-sensitized photovoltaic (DSPV) cell
and the progress in current research. The important contributions of molecular dyes that are used as photosensitizers in these
photovoltaic or solar cells are also described. 相似文献
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Ravi C. Paul William Swart Aixiu Monica Zhang Kenneth R. MacLeod 《Distance Education》2015,36(3):364-382
Transactional distance has been defined as barriers to students’ engagement with learning in the online environment. This research updates Zhang’s (2003) scale of transactional distance, which quantified the extent of the barriers, in light of the massive changes in today’s web-based learning environment. The resulting revised scale of transactional distance (RSTD) is a parsimonious version with 12 elements (compared to 31 original) that measure the transactional distance between student and teacher, student and student, and student and content. The RSTD has excellent factorial validity and reliability, yields better fit statistics, and is easier and less time-consuming to apply. The transactional distance values are unique predictors of student satisfaction, which is correlated to learning and persistence (a major concern with massive open online courses). This information can form the basis for a systematic approach to improving the design of today’s contemporary open, flexible, distance education courses and thus serve as a valuable tool for researchers and educators alike. 相似文献
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Kim Normann Andersen Rony Medaglia Ravi Vatrapu Helle Zinner Henriksen Robin GauldAuthor vitae 《Government Information Quarterly》2011,28(4):439-445
Assessing e-government responsiveness is one of the major gaps in the currently dominant e-government maturity models. While we have a relatively large pool of models focusing on technological and organizational integration from a supply side perspective, measures of responsiveness of e-government systems from a user perspective are still lacking. Replicating a study from New Zealand and Australia, this study explores the response time and quality of e-mail response in Danish local and central governments (N = 175). Despite that Denmark is high ranking in international benchmark studies, we find that one third of central government agencies did not respond at all, and close to 80% of the ministries provided none or incomplete answers. Local government responds faster and provides answers that are more complete and accurate than those provided by central government. Implications for e-government are discussed. 相似文献
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Ritu Sharma Mridula Mahajan Ravi Kant 《Indian journal of clinical biochemistry : IJCB》2004,19(1):10-13
Serum total lipids (cholesterol and triglyceride), lipoproteins (VLDL, LDL and HDL) and Apolipoprotein-B levels of normal
healthy individuals (n=25) and coronary artery disease patients (n=25) were estimated. The objective of the present study
was to ascertain the role of apo-B in causation and inheritance of coronary artery disease. It was observed that on an average
serum total cholesterol and triglyceride more than 200 mg/dl bring the individuals to a risk of coronary artery disease (CAD)
irrespective of the age. CAD patients achieved this value at an early age (35–45 years). Similarly VLDL and LDL levels were
found to be significantly raised in CAD patients when compared to that of age matched normal individuals, with patients achieving
risk values at an early age. HDL levels were found to be significantly lower in CAD patients as compared to normal individuals.
Serum apo-B levels were significantly raised in CAD patients as compared to age matched normal individuals. Patients with
positive family history of CAD had raised serum apo-B levels than those having negative family history. A positive coefficient
of correlation was observed between serum apo-B and LDL levels suggesting that more the number of Apo-B particles, more will
be the synthesis of atherogenic particle (LDL). Patients with negative family history had serum apo-B levels closer to those
of normal individuals and in these individuals HDL levels were found to be significantly lowered, suggesting that loss of
scavenger role of HDL could be the risk factor responsible for the causation of CAD in these patients, with negative family
history of coronary artery disease. 相似文献
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Anuradha Bharosay Vivek Vikram Bharosay Kiran Saxena Meena Varma 《Indian journal of clinical biochemistry : IJCB》2018,33(2):178-183
This study was undertaken to evaluate the role of serum neuron specific enolase (NSE) in prediction of disability and neurological worsening in hypertensive ischemic cerebrovascular stroke. 80 hypertensive ischemic stroke patients diagnosed by a neurologist as per WHO definition along with radiological findings suggestive of cerebrovascular stroke and differentiating from hemorrhagic stroke and 60 controls having essential hypertension coming to hospital because of regular checkup or headache but with no neurological disease were included in the study. Neurological disability was assessed by NIHSS at the time of admission (within 72 h from the onset of stroke) and on 7th day after admission and cases were categorized into mild, moderate and severe disability. Venous blood samples were drawn within 72 h from the onset of symptoms. The samples were processed as per the laboratory protocol. The serum NSE samples were analyzed using an enzyme immunoassay based on the sandwich technique. We observed raised serum NSE in hypertensive ischemic stroke (17.4 ± 5.4 ng/ml) with significant association between different hypertensive groups than in hypertensive controls (9.1 ± 0.75 ng/ml). Greater degree of disability was observed in hypertensive stroke patients with raised serum NSE and hypertensive patients with mean serum NSE level of 22.9 ± 3.6 ng/ml and dyslipidemia had greater probability of neurological worsening as compared to those with mean serum NSE level of 12.7 ± 1.2 ng/ml. Serum NSE levels can serve as a peripheral indicator of neuronal damage and assist in the prediction of disability and clinical outcome in hypertensive cerebrovascular ischemic stroke patients. 相似文献
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A. Ravi Raja G. N. Vishal Babu Geraldine Menezes T. Venkatesh 《Indian journal of clinical biochemistry : IJCB》2008,23(2):200-203
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
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R. P. Saxena 《Higher Education》1990,20(1):91-111
India with a current student population of around 4 million in its universities and colleges is the third largest system in the world after USA and USSR. The unprecedented expansion of higher education in India, which took place in the last four decades, has, however, been extremely uneven and resulted in the neglect of quality, research and managements aspects. The universities and colleges function much below their optimal levels and fail even to fulfil their minimum and basic tasks such as making admissions, completing teaching, conducting examinations, declaring results and awarding degrees on time. The very credibility of the university system stands eroded.Increasing government control, extra-constitutional pressures in their governance, appointment and dismissal of Vice-Chancellors on political considerations and drift of the academic community from serious academic pursuits have undermined the autonomy of the universities. The paper attempts to analyse from macro-micro angles the causes for the decay of the university system.The National Policy on Education-1986 aims at radical reorganisation of higher education to bring about dynamism in the system through multi-pronged strategies and programmes and structural reforms. Policy interventions have, however, failed to create much impact. The paper brings forth some of the important issues vital to the governance of the universities and highlights the need for a collective endeavour of teachers, students, educational administrators and government and rigorous system of performance audit to bring dynamism into the system. 相似文献
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Ravi Rampersad 《British Journal of Sociology of Education》2014,35(1):73-93
Bourdieu describes capital as the political building blocks of social order that give meaning to social accumulation and consumption. Through a combination of Bourdieu’s sociology and critical race theory, this sojourn into Afro-Trinidadian boys’ achievement seeks to elucidate an approach to understanding capital as inherently raced. This is premised on an interrogation of Trinidadian society as pigmentocratically structured, where lightness is rewarded with a myriad of social advantages, and darkness denigrated as illegitimate and ‘other’. The premium placed on lighter skin is manifested interdependently in the forms of social, economic and cultural capital. As such, the operation of capital as politic not only reflects societal structures of power and domination, but importantly also contributes in the maintenance of said structures. The concept of ‘Racialised facilitative capital’ follows as inseparably both facilitator of social status and as racialised process. 相似文献