General Relativistic effects on the conversion of nuclear to two-flavour quark matter in compact stars

We investigate the General Relativistic (GR) effects on the conversion from nuclear to two-flavour quark matter in compact stars, both static as well as rotating. We find that GR effects lead to qualitative differences in rotating stars, indicating the inadequacy of non-relativistic (NR) or even Special Relativistic (SR) treatments for these cases.Comment: 4 pages, 4 figure

Modeling and Simulation of Dewatering of Particulate Suspensions by Batch Pressure Filtration

A Darcy law based approach for simulation of batch const-ant pressure filtration of particulate suspensions when the feed solids concentration changes, is developed. Using filtration data obtained using a feed suspension with a not-very-low solids concentration, we propose procedures to predict changes in (0 kinetics of dewatering in the cake formation stage, and (ii)transition point between the cake formation and consolidation stages, as the initial solid concentration changes. The evolution of dewatering can be predicted using these two model parameters. The approach is simpler to implement in comparison to avail-able pressure filtration models which require several char acterization experiments

Growing pseudo-eigenmodes and positive logarithmic norms in rotating shear flows

Rotating shear flows, when angular momentum increases and angular velocity decreases as functions of radiation coordinate, are hydrodynamically stable under linear perturbation. The Keplerian flow is an example of such systems which appears in astrophysical context. Although decaying eigenmodes exhibit large transient energy growth of perturbation which could govern nonlinearity into the system, the feedback of inherent instability to generate turbulence seems questionable. We show that such systems exhibiting growing pseudo-eigenmodes easily reach an upper bound of growth rate in terms of the logarithmic norm of the involved nonnormal operators, thus exhibiting feedback of inherent instability. This supports the existence of turbulence of hydrodynamic origin in the Keplerian accretion disc in astrophysics. Hence, this enlightens the mismatch between the linear theory and experimental/observed data and helps in resolving the outstanding question of origin of turbulence therein.Comment: 12 pages including 4 figures; to appear in New Journal of Physic

A pathway model of glucose-stimulated insulin secretion in the pancreatic β-cell

The pancreas plays a critical role in maintaining glucose homeostasis through the secretion of hormones from the islets of Langerhans. Glucose-stimulated insulin secretion (GSIS) by the pancreatic β-cell is the main mechanism for reducing elevated plasma glucose. Here we present a systematic modeling workflow for the development of kinetic pathway models using the Systems Biology Markup Language (SBML). Steps include retrieval of information from databases, curation of experimental and clinical data for model calibration and validation, integration of heterogeneous data including absolute and relative measurements, unit normalization, data normalization, and model annotation. An important factor was the reproducibility and exchangeability of the model, which allowed the use of various existing tools. The workflow was applied to construct a novel data-driven kinetic model of GSIS in the pancreatic β-cell based on experimental and clinical data from 39 studies spanning 50 years of pancreatic, islet, and β-cell research in humans, rats, mice, and cell lines. The model consists of detailed glycolysis and phenomenological equations for insulin secretion coupled to cellular energy state, ATP dynamics and (ATP/ADP ratio). Key findings of our work are that in GSIS there is a glucose-dependent increase in almost all intermediates of glycolysis. This increase in glycolytic metabolites is accompanied by an increase in energy metabolites, especially ATP and NADH. One of the few decreasing metabolites is ADP, which, in combination with the increase in ATP, results in a large increase in ATP/ADP ratios in the β-cell with increasing glucose. Insulin secretion is dependent on ATP/ADP, resulting in glucose-stimulated insulin secretion. The observed glucose-dependent increase in glycolytic intermediates and the resulting change in ATP/ADP ratios and insulin secretion is a robust phenomenon observed across data sets, experimental systems and species. Model predictions of the glucose-dependent response of glycolytic intermediates and biphasic insulin secretion are in good agreement with experimental measurements. Our model predicts that factors affecting ATP consumption, ATP formation, hexokinase, phosphofructokinase, and ATP/ADP-dependent insulin secretion have a major effect on GSIS. In conclusion, we have developed and applied a systematic modeling workflow for pathway models that allowed us to gain insight into key mechanisms in GSIS in the pancreatic β-cell.Peer Reviewe

Leader RNA of Rinderpest virus binds specifically with cellular La protein: a possible role in virus replication

Rinderpest virus (RPV) is an important member of the Morbillivirus genus in the family Paramyxoviridae and employs a similar strategy for transcription and replication of its genome as that of other negative sense RNA viruses. Cellular proteins have earlier been shown to stimulate viral RNA synthesis by isolated nucleocapsids from purified virus or from virus-infected cells. In the present work, we show that plus sense leader RNA of RPV, transcribed from 3' end of genomic RNA, specifically interacts with cellular La protein employing gel mobility shift assay as well as UV cross-linking of leader RNA with La protein. The leader RNA synthesized in virus-infected cells was shown to interact with La protein by immunoprecipitation of leader RNA bound to La protein and detecting the leader RNA in the immunoprecipitate by Northern hybridization with labeled antisense leader RNA. Employing a minireplicon system, we demonstrate that transiently expressed La protein enhances the replication/transcription of the RPV minigenome in cells. Sub-cellular immunolocalization shows that La protein is redistributed from nucleus to the cytoplasm upon infection. Our results strongly suggest that La protein may be involved in regulation of Rinderpest virus replication

The effect of endurance exercise on both skeletal muscle and systemic oxidative stress in previously sedentary obese men

Background: Obesity is associated with low-grade systemic inflammation, in part because of secretion of proinflammatory cytokines, resulting into peripheral insulin resistance (IR). Increased oxidative stress is proposed to link adiposity and chronic inflammation. The effects of endurance exercise in modulating these outcomes in insulin-resistant obese adults remain unclear. We investigated the effect of endurance exercise on markers of oxidative damage (4-hydroxy-2-nonenal (4-HNE), protein carbonyls (PCs)) and antioxidant enzymes (superoxide dismutase (SOD), catalase) in skeletal muscle; urinary markers of oxidative stress (8-hydroxy-2-deoxyguanosine (8-OHdG), 8-isoprostane); and plasma cytokines (C-reactive protein (CRP), interleukin-6 (IL-6), leptin, adiponectin). Methods: Age- and fitness-matched sedentary obese and lean men (n=9 per group) underwent 3 months of moderate-intensity endurance cycling training with a vastus lateralis biopsy, 24-h urine sample and venous blood samples taken before and after the intervention. Results: Obese subjects had increased levels of oxidative damage: 4-HNE (+37% P⩽0.03) and PC (+63% P⩽0.02); evidence of increased adaptive response to oxidative stress because of elevated levels of copper/zinc SOD (Cu/ZnSOD) protein content (+84% P⩽0.01); increased markers of inflammation: CRP (+737% P⩽0.0001) and IL-6 (+85% P⩽0.03), and these correlated with increased markers of obesity; and increased leptin (+262% P⩽0.0001) with lower adiponectin (−27% P⩽0.01) levels vs lean controls. Training reduced 4-HNE (−10% P⩽0.04), PC (−21% P⩽0.05), 8-isoprostane (−26% P⩽0.02) and leptin levels (−33% P⩽0.01); had a tendency to decrease IL-6 levels (−21% P=0.07) and IR (−17% P=0.10); and increased manganese SOD (MnSOD) levels (+47% P⩽0.01). Conclusion: Endurance exercise reduced skeletal muscle-specific and systemic oxidative damage while improving IR and cytokine profile associated with obesity, independent of weight loss. Hence, exercise is a useful therapeutic modality to reduce risk factors associated with the pathogenesis of IR in obesity

The conversion of Neutron star to Strange star : A two step process

The conversion of neutron matter to strange matter in a neutron star have been studied as a two step process. In the first step, the nuclear matter gets converted to two flavour quark matter. The conversion of two flavour to three flavour strange matter takes place in the second step. The first process is analysed with the help of equations of state and hydrodynamical equations, whereas, in the second process, non-leptonic weak interaction plays the main role. Velocities and the time of travel through the star of these two conversion fronts have been analysed and compared.Comment: 18 pages including 9 figure

PENGARUH MODAL SOSIAL TERHADAP PRODUKTIVITAS PETANI (STUDI KASUS DI KECAMATAN SERBAJADI KABUPATEN SERDANG BEDAGAI)

Social welfare relates to social conditions, where social issues can be addressed satisfactorily, social needs can be fulfilled well, having a sense of security in life and freely open social opportunities. Social capital that exists in the community can enrich the community and can even minimize the chances of conflict. The type of contribution of the agricultural sector in Serdang District Bedagai is the largest produced by the commodity of food crops (BPS, 2014). Decision of farmers to grow crops because it is based on the needs of eating farmers ' families as well as the price of food ingredients are increasingly expensive. The high value of social capital that is owned by a region can help farmers in terms of production, distribution and innovation. Based on the explanation, researchers are interested in researching how big the social capital is on farmers in the district of Serba Jadi, then its influence on the productivity of existing farmers in the sub-district of Serdang Bedagai District. The role of capital can help increase agricultural productivity, but not many people acknowledge that the increase of human capital and social capital can raise the productivity of farmers, while the productivity of farmers in District Department of district Serdang Bedagai is low. This research aims to determine the influence of social capital both partially and simultaneously to the productivity of farmers in the subdistrict of Serdang Bedagai district.This research uses a quantitative approach. Data collection techniques use questionnaires and documentation, while data analysis techniques use double regression analysis. The results showed that: (1) Variable Trust has no positive effect on farmer productivity (2) Participation variables have no positive effect on farmer productivity (3) network variables have no positive effect To farmer productivity (4) variable social norms positively and significantly influence on farmers ' productivity (5) Variable trust, participation, networking, and social norms positively influence together towards productivity Farmers

Safety and efficacy of del Nido cardioplegia in adult cardiac surgery: experience in NICVD

Background: Cardioplegia is used to induce and provide a depolarized diastolic cardiac arrest to provide a motionless surgical field. Del Nido cardioplegia solution has been used extensively in congenital heart surgery for more than 20 years and more recently for adults. This observational study was performed to assess the safety and efficacy of del Nido cardioplegia in adult cardiac surgery patients. Methods: Total 140 adult patients selected for cardiac surgical procedure i.e., coronary artery bypass grafting (CABG), valve surgery, or CABG with valve surgery no need requiring cardiopulmonary bypass (CPB) were purposively allocated into two groups: a) del Nido cardioplegia (n=70) and b) blood cardioplegia (n=70). Primary outcomes assessed myocardial preservation. Results: The study compared del Nido (A) and blood cardioplegia (B) groups. Mean ages were 49.5±7.86 and 48.9±6.79 years, respectively (p=0.5641). BMI (26.98±2.3 vs 27.2±2.14 kg/m2, p=0.4846) and comorbid factors, including smoking (48% versus 51%) were similar. Differences were lower hemoglobin in A (males: 11.7±1.18 versus 13.6±0.55; females: 10.2±0.58 versus 12.2±0.21, p<0.0001) and CPB/ACC times for isolated CABG (A: 112.40±15.75/78.45±11.65 versus B: 123.8±18.55/86.28±15.26 minutes, p=0.0001). Post-operatively, more blood loss occurred in A, but they had shorter mechanical ventilation, ICU stay, and hospital stay durations. Other variables, like 30-day mortality, were similar. Conclusions: Evidence from this study suggests del Nido cardioplegia use in routine adult cases may be safe, result in comparable clinical outcomes, and streamline surgical workflow. The trend for troponin should be investigated further because it may suggest superior myocardial protection with the del Nido solution