934 research outputs found
Breeding of Indian major carps and common carp in semi-arid zone of Haryana under controlled environment
Vast barren lands are lying vacant in the semi-arid zone of India, which can effectively be utilised for fish farming. Experiments conducted in semi-arid conditions at Damdama indicated that it is possible to breed Indian major carps and common carp under controlled conditions of modern carps hatchery CIFE D-80 without depending on rain
Microenvironment-induced downregulation of miR-193b drives ovarian cancer metastasis
The cross-talk between ovarian cancer (OvCa) cells and the metastatic microenvironment is an essential determinant of successful colonization. MicroRNAs (miRNAs) have several critical roles during metastasis; however, the role of microenvironmental cues in the regulation of miRNAs in metastasizing cancer cells has not been studied. Using a three-dimensional culture model that mimics the human omentum, one of the principal sites of OvCa metastasis, we identified and characterized the microenvironment-induced downregulation of a tumor suppressor miRNA, miR-193b, in metastasizing OvCa cells. The direct interaction of the OvCa cells with mesothelial cells, which cover the surface of the omentum, caused a DNA methyltransferase 1-mediated decrease in the expression of miR-193b in the cancer cells. The reduction in miR-193b enabled the metastasizing cancer cells to invade and proliferate into human omental pieces ex vivo and into the omentum of a mouse xenograft model of OvCa metastasis. The functional effects of miR-193b were mediated, in large part, by the concomitant increased expression of its target, urokinase-type plasminogen activator, a known tumor-associated protease. These findings link paracrine signals from the microenvironment to the regulation of a key miRNA in cancer cells. Targeting miR-193b, which is essential for metastatic colonization of cancer cells could prove effective in the treatment of OvCa metastasis
Systematic daytime increases in atmospheric biases linked to dry soils in irrigated areas in Indian operational forecasts
The representation of land–atmosphere coupling in forecast models can significantly impact weather prediction. A previous case study in Northern India incorporating both model and observational data identified atmospheric biases in a high-resolution forecast linked to soil moisture that impacted the representation of the monsoon trough, an important driver of regional rainfall. The aim of the current work is to understand whether this behavior is present in operational forecasts run by the India National Centre for Medium Range Weather Forecasting (NCMRWF). We utilize satellite observations and reanalysis to evaluate model fields in June, July, August, and September forecasts from 2020. Our analysis reveals systematic rapid growth in warm boundary layer biases during the daytime over North West India, which weaken overnight, consistent with excessive daytime surface sensible heat flux. The cumulative effect of these biases produces temperatures more than 4K warmer in 60-h forecasts. These effects are enhanced by dry surface conditions. The biases impact circulation in the forecasts, which have implications for regional rainfall. The spatial distribution of warm biases in the Indo-Gangetic Plain is remarkably consistent with the location of areas equipped for irrigation, a process that is not explicitly represented in the model. Our results provide compelling evidence that the development of an irrigation scheme within the model is needed to address the substantial forecast biases that we document
Dynamics of an anisotropic Haldane antiferromagnet in strong magnetic field
We report the results of elastic and inelastic neutron scattering experiments
on the Haldane gap quantum antiferromagnet Ni(C5D14N2)2N3(PF6) performed at mK
temperatures in a wide range of magnetic field applied parallel to the S = 1
spin chains. Even though this geometry is closest to an ideal axially symmetric
configuration, the Haldane gap closes at the critical field Hc~4T, but reopens
again at higher fields. The field dependence of the two lowest magnon modes is
experimentally studied and the results are compared with the predictions of
several theoretical models. We conclude that of several existing theories, only
the recently proposed model [Zheludev et al., cond-mat/0301424 ] is able to
reproduce all the features observed experimentally for different field
orientations.Comment: 11 pages 8 figures submitted to Phys. Rev.
Adjustment of the electric current in pulsar magnetospheres and origin of subpulse modulation
The subpulse modulation of pulsar radio emission goes to prove that the
plasma flow in the open field line tube breaks into isolated narrow streams. I
propose a model which attributes formation of streams to the process of the
electric current adjustment in the magnetosphere. A mismatch between the
magnetospheric current distribution and the current injected by the polar cap
accelerator gives rise to reverse plasma flows in the magnetosphere. The
reverse flow shields the electric field in the polar gap and thus shuts up the
plasma production process. I assume that a circulating system of streams is
formed such that the upward streams are produced in narrow gaps separated by
downward streams. The electric drift is small in this model because the
potential drop in narrow gaps is small. The gaps have to drift because by the
time a downward stream reaches the star surface and shields the electric field,
the corresponding gap has to shift. The transverse size of the streams is
determined by the condition that the potential drop in the gaps is sufficient
for the pair production. This yields the radius of the stream roughly 10% of
the polar cap radius, which makes it possible to fit in the observed
morphological features such as the "carousel" with 10-20 subbeams and the
system of the core - two nested cone beams.Comment: 8 pages, 1 figur
Massive triplet excitations in a magnetized anisotropic Haldane spin chain
Inelastic neutron scattering experiments on the Haldane-gap quantum
antiferromagnet \nd are performed at mK temperatures in magnetic fields of
almost twice the critical field applied perpendicular to the spin cahins.
Above a re-opening of the spin gap is clearly observed. In the high-field
N\'eel-ordered state the spectrum is dominated by three distinct long-lived
excitation branches. Several field-theoretical models are tested in a
quantitative comparison with the experimental data.Comment: 4 pages, 3 figure
Current opportunities and challenges in developing hydro-climatic services in the Himalayas: report of pump priming project November 2019
The India-UK Water Centre (IUKWC) promotes cooperation and collaboration between the complementary priorities of NERC-MoES water security research.
This report assesses the significant issues for hydro-climatic modelling and service development in the mountain regions of northern India. It is the main output from an IUKWC Pump Priming Project that ran from March to August 2018 and has been produced by an author team of climate scientist, hydrologists and glaciologist from India and the UK. It is found that although state-ofthe-art weather forecasting, climate, hydrological and glacier models are being used there are still substantial prediction uncertainties on all prediction timescales. There is a lack of detailed understanding of regional meteorological and hydrological processes, which results in potential misrepresentation of them in the models. Large-scale drivers of regional climate variability in the region have been identified but questions remain about their relevance on different timescales, their interaction, and their representation in global weather forecasting and climate models. Improving short-term predictions and climate change projections requires more meteorological, hydrological and glaciological observations in the Himalayas, improvements in data sharing, as well as additional efforts to integrate meteorological and hydrological modelling. There is also a need for improved communication of predictions to users, which should include their uncertainties.
The report is intended for workshop participants, India-UK Water Centre Open Network members and stakeholders
Fuzzy Intervals for Designing Structural Signature: An Application to Graphic Symbol Recognition
Revised selected papers from Eighth IAPR International Workshop on Graphics RECognition (GREC) 2009.The motivation behind our work is to present a new methodology for symbol recognition. The proposed method employs a structural approach for representing visual associations in symbols and a statistical classifier for recognition. We vectorize a graphic symbol, encode its topological and geometrical information by an attributed relational graph and compute a signature from this structural graph. We have addressed the sensitivity of structural representations to noise, by using data adapted fuzzy intervals. The joint probability distribution of signatures is encoded by a Bayesian network, which serves as a mechanism for pruning irrelevant features and choosing a subset of interesting features from structural signatures of underlying symbol set. The Bayesian network is deployed in a supervised learning scenario for recognizing query symbols. The method has been evaluated for robustness against degradations & deformations on pre-segmented 2D linear architectural & electronic symbols from GREC databases, and for its recognition abilities on symbols with context noise i.e. cropped symbols
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