1,181 research outputs found

    A note on new indices for the equatorial Indian Ocean oscillation

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    It is now well known that there is a strong association of the extremes of the Indian summer monsoon rainfall (ISMR) with the El Niño and southern oscillation (ENSO) and the Equatorial Indian Ocean Oscillation (EQUINOO), later being an east-west oscillation in convection anomaly over the equatorial Indian Ocean. So far, the index used for EQUINOO is EQWIN, which is based on the surface zonal wind over the central equatorial Indian Ocean. Since the most important attribute of EQUINOO is the oscillation in convection/precipitation, we believe that the indices based on convection or precipitation would be more appropriate. Continuous and reliable data on outgoing longwave radiation (OLR), and satellite derived precipitation are now available from 1979 onwards. Hence, in this paper, we introduce new indices for EQUINOO, based on the difference in the anomaly of OLR/precipitation between eastern and western parts of the equatorial Indian Ocean. We show that the strong association of extremes of the Indian summer monsoon with ENSO and EQUINOO is also seen when the new indices are used to represent EQUINOO

    The aberrant behaviour of the Indian monsoon in June 2009

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    After an early onset over Kerala on 23 May 2009, further advance of the monsoon over the Indian region was delayed by about two weeks with the monsoon restricted to the west coast and southern peninsula until 24 Jun

    Advances in DNA Affinity Chromatography

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    Different aspects of DNA affinity chromatography such as DNA complexity heparin elution, the Bi-column method and the oligonucluotide trapping method were studied. The complexity (length) of a DNA sequence attached to an affinity chromatography column affects column retention, and the purity of transcription factors obtained. T18: A18 tailed DNA affinity columns were better suited for purification of most of the transcription factors than either the discrete or concatemeric DNA affinity columns. A novel method using heparin for eluting transcription factors from DNA Sepharose columns was characterized. The amount of the lac repressor chimera which eluted from the column was shown to increase with increases in the mobile phase heparin concentration. The elution of the protein was also shown to be dependent on the amount of DNA coupled to the column and more protein eluted from columns containing lesser amounts of DNA. These data suggest that heparin and DNA compete for binding to the protein; this competition causes elution. Comparison of heparin- and salt-eluted protein demonstrated the heparin-eluted fraction of lac repressor was significantly purer than that eluted with salt and comparable to that obtained by elution with the specific ligand IPTG, a lactose analog. A novel Bi-column method was developed in which lac repressor is eluted from the Op1-Sepharose with a low heparin concentration and trapped on a Op1T18-Sepharose column because of its higher affinity for the lac repressor protein. Elution of the latter column with buffer containing a high salt concentration gives significantly purer transcription factor than the conventionally used single column methods and removes residual heparin. Highly pure CAAT enhancer binding protein(C/EBP) and the B3 transcription factor are also obtained by using variants of this Bi-column method. A new oligonucleotide trapping method in which a short oligonucleotide coupled to Sepharose is used to trap a complex of the transcription factor and its corresponding specific DNA sequence was developed. Highly purified transcription factor B3 was obtained using the oligonucleotide trapping method

    Current status and management of scientific information relating to Indian environment

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    To address the important challenge of taking good care of India’s environment, we require substantial, good quality, and reliable information. Unfortunately, such information is in very short supply. Most of it is collected through the state machinery. With a few notable exceptions like India Meteorological Department and the Indian Space Research Organization, the agencies involved exhibit a number of shortcomings. These include: (1) Failure to maintain records, (2) Very patchy, incomplete information, (3) Suppression of accurate information, (4) Deliberately falsified information, (5) Failure to make information publicly available, and (6) Failure to involve public in generating useful information. Three significant avenues for involving the public in generating useful environmental information, namely, preparation of ward-wise Environmental Status Reports by Local Bodies under the 73rd and 74th Constitutional Amendments, preparation of People’s Biodiversity Registers by Local Bodies under Biological Diversity Act, and compilation of information generated through student projects under educational system-wide compulsory Environmental Education courses are being scarcely tapped. To address this challenge, the Ministry of Environment, Forest and Climate Change (MOEF&CC) established around 1983 an Environmental Information System whose 68 centers focus on newsletters, research papers, court orders, etc. and little on useable environmental databases. In view of this inadequacy MOEF & CC started a new environmental information facility called the Environmental Information Centre in 2002. Regretfully EIC has altogether stopped functioning around 2010. Evidently, the prevalent exclusionary culture of bureaucratic management of information cannot be maintained in the modern, open democratic society of India. In response, the Government has promulgated the National Data Sharing and Accessibility Policy and set up a Nataional Spatial Data Infrastructure. This ought to lead to a sustained effort to geocode environmental information and make it available as GIS ready datasets. To this end, we need to start a fresh initiative to create a new Environment Infromation Infrastructure that can act as an umbrella platform to collate and disseminate environmental information in the country . We must also strive towards creating partnerships with public sector and private sector digital platforms, in particular (a) ISRO’s Bhuvan and (b) Google Public Data Explorer. To these proposals, we must now add one more dimension, namely, that the information system should not only be publicly accessible, but be a participatory system involving all interested citizens. It should be broad in scope and involve not only various Central and State Government agencies, but also all the Local Bodies and organizations such as industries and mines that are expected to document their pertinent activities. However, the fact that with the notable exception of the Sikkim springs programme of the Government of Sikkim, several long-standing opportunities such as Biological Diversity Act have so far not led to any concrete actions, indicates that the citizens must step in and take the initiative on their own. Such a people’s movement for making good environmental information openly available could very effectively piggyback on the hugely successful Wikipedia experiment

    Application of Frequency Estimation Techniques to Minimize Power Quality Problem

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    Through the use of a technique known as frequency estimation, the objective of this study is to explore a topic that pertains to power quality and the elimination of harmonics in the power system. Under a wide range of less-than-ideal conditions, such as voltage imbalance, harmonics, dc-offset, and so on, the objective of this research is to investigate the performance of a number of different methodologies for estimating phase and frequency. The bulk of the techniques have been shown to be incapable of estimating the frequency of the grid signals when the grid signals are characterized by dc-offset. This has been demonstrated via the use of a number of different methods. An approach to frequency estimation that is referred to as modified dual second order generalized (MDSOGI) is presented in this article. Under all of the circumstances that are not perfect, this technique makes an accurate prediction as to the frequency with which it occurs. It has been shown by experiments that the results are correct. It is necessary to further integrate the control scheme with the notion of instantaneous reactive power in order to construct a control scheme for a shunt active power filter that is capable of functioning under such conditions. A prototype for the experimental system is now being developed in order to show improved performance capacity

    Measures of Health-Related Quality of Life Outcomes in Pediatric Neurosurgery: Literature Review

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    Background Improving value in healthcare means optimizing outcomes and minimizing costs. The emerging pay-for-performance era requires understanding of the effect of healthcare services on health-related quality of life (HRQoL). Pediatric and surgical subspecialties have yet to fully integrate HRQoL measures into practice. The present study reviewed and characterized the HRQoL outcome measures across various pediatric neurosurgical diagnoses. Methods A literature review was performed by searching PubMed and Google Scholar with search terms such as “health-related quality of life” and “pediatric neurosurgery” and then including the specific pathologies for which a HRQoL instrument was found (e.g., “health-related quality of life” plus “epilepsy”). Each measurement was evaluated by content and purpose, relative strengths and weaknesses, and validity. Results We reviewed 68 reports. Epilepsy, brain tumor, cerebral palsy, spina bifida, hydrocephalus, and scoliosis were diagnoses found in reported studies that had used disease-specific HRQoL instruments. Information using general HRQoL instruments was also reported. Internal, test–retest, and/or interrater reliability varied across the instruments, as did face, content, concurrent, and/or construct validity. Few instruments were tested enough for robust reliability and validity. Significant variability was found in the usage of these instruments in clinical studies within pediatric neurosurgery. Conclusions The HRQoL instruments used in pediatric neurosurgery are currently without standardized guidelines and thus exhibit high variability in use. Clinicians should support the development and application of these methods to optimize these instruments, promote standardization of research, improve performance measures to reflect clinically modifiable and meaningful outcomes, and, ultimately, lead the national discussion in healthcare quality and patient-centered care

    Monsoon prediction - Why yet another failure?

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    The country experienced a deficit of 13 in the summer monsoon of 2004. As in 2002, this deficit was not predicted either by the operational empirical models at India Meteorological Department (IMD) or by the dynamical models at national and international centres. Our analysis of the predictions generated by the operational models at IMD from 1932 onwards suggests that the forecast skill has not improved over the seven decades despite continued changes in the operational models. Clearly, new approaches need to be explored with empirical models. The simulation of year-to-year variation of the monsoon is still a challenging problem for models of the atmosphere as well as the coupled ocean-atmosphere system. We expect dynamical models to generate better prediction only after this problem is successfully addressed

    Monsoon variability: Links to major oscillations over the equatorial Pacific and Indian oceans

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    In this article, we first discuss our perception of the factors which are critical for inter-annual variation of the Indian summer monsoon rainfall and the major milestones leading to this understanding. The nature of the two critical modes for monsoon variability, viz. El Nino Southern Oscillation and equatorial Indian Ocean Oscillation is considered and their links to the monsoon elucidated. We suggest possible reasons for the rather poor skill of simulation of the interannual variation of the Indian summer monsoon rainfall by atmospheric general circulation models, run with the observed sea surface temperature as boundary condition. We discuss implications of what we have learned for the monsoon of 2006, and possible use of information on the two important modes for prediction of the rainfall in all or part of the summer monsoon season. We conclude with our view of what the focus of research and development should be for achieving a substantial improvement in the skill of simulation and prediction of the Indian summer monsoon rainfall in the near future

    Parking and the visual perception of space

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    Using measured data we demonstrate that there is an amazing correspondence among the statistical properties of spacings between parked cars and the distances between birds perching on a power line. We show that this observation is easily explained by the fact that birds and human use the same mechanism of distance estimation. We give a simple mathematical model of this phenomenon and prove its validity using measured data
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