2,328 research outputs found
Thermodynamics of Neutral Protein Evolution
Naturally evolving proteins gradually accumulate mutations while continuing
to fold to thermodynamically stable native structures. This process of neutral
protein evolution is an important mode of genetic change, and forms the basis
for the molecular clock. Here we present a mathematical theory that predicts
the number of accumulated mutations, the index of dispersion, and the
distribution of stabilities in an evolving protein population from knowledge of
the stability effects (ddG values) for single mutations. Our theory
quantitatively describes how neutral evolution leads to marginally stable
proteins, and provides formulae for calculating how fluctuations in stability
cause an overdispersion of the molecular clock. It also shows that the
structural influences on the rate of sequence evolution that have been observed
in earlier simulations can be calculated using only the single-mutation ddG
values. We consider both the case when the product of the population size and
mutation rate is small and the case when this product is large, and show that
in the latter case proteins evolve excess mutational robustness that is
manifested by extra stability and increases the rate of sequence evolution. Our
basic method is to treat protein evolution as a Markov process constrained by a
minimal requirement for stable folding, enabling an evolutionary description of
the proteins solely in terms of the experimentally measureable ddG values. All
of our theoretical predictions are confirmed by simulations with model lattice
proteins. Our work provides a mathematical foundation for understanding how
protein biophysics helps shape the process of evolution
CORBYS cognitive control architecture for robotic follower
In this paper the novel generic cognitive robot control architecture CORBYS is presented. The objective of the CORBYS architecture is the integration of high-level cognitive modules to support robot functioning in dynamic environments including interacting with humans. This paper presents the preliminary integration of the CORBYS architecture to support a robotic follower. Experimental results on high-level empowerment-based trajectory planning have demonstrated the effectiveness of ROS-based communication between distributed modules developed in a multi-site research environment as typical for distributed collaborative projects such as CORBYS
Uterine rupture: a preventable obstetric catastrophe
Background: Maternal health has long been acknowledged to be the cornerstone in public health. The objective of this study was to determine the incidence, etiology, risk factors, complications, treatment strategies, maternal and fetal outcome associated with uterine rupture and to determine how to decrease the maternal morbidity and mortality pertaining to it, as it is indeed a preventable obstetric catastrophe!Methods: This is a retrospective study which was carried out in our institute. Analysis of 45 cases of uterine rupture including scar dehiscence, registered/emergency, rupture occurring in the antepartum or intrapartum period, irrespective of previous vaginal or cesarean delivery was done between July 2017 to June 2019 out of 16,330 deliveries. None of the cases were excluded. Statistical analysis was done comparing the mortality in general population and study population and it was determined that it contributes to the maternal mortality significantly hence making it essential to promptly diagnose and treat the cases.Results: The incidence of rupture of uterus is average 0.27% (1 in 362). Out of 45 cases 9 (20%) were registered, and 36 (80%) were referred patients. The 20-30 years age group is the most vulnerable. Scarred uterus undergoing rupture were 34 (75.55%) as compared to rupture in intact uterus which were 11 (24.44%). The commonest modality of treatment used is suturing of tear which was done in 34 (75.55%) followed by total hysterectomy. There were 2 maternal deaths giving maternal mortality rate of 4.44% and perinatal mortality occurred in 18 (40%) cases.Conclusions: Uterine rupture is a dire emergency with a high incidence of maternal and fetal morbidity and mortality. Skilled attendance with accessible obstetric care, focused antenatal care, strict intrapartum monitoring and good surgical approach are key elements for the prevention and management of uterine rupture
Research and development work carried out on edible oysters in Gujarat
Oyster resources survey was conducted by
the transect method from Jakhau in the Gulf of
Kutch to Umargaon in south Gujarat. Crassostrea
gryphoides was dominant followed by Saccostrea
cucullata and C. rividari
Explaining the increased health care expenditures associated with gastroesophageal reflux disease among elderly Medicare beneficiaries with chronic obstructive pulmonary disease: a cost-decomposition analysis
Objective: To estimate excess health care expenditures associated with gastroesophageal reflux disease (GERD) among elderly individuals with chronic obstructive pulmonary disease (COPD) and examine the contribution of predisposing characteristics, enabling resources, need variables, personal health care practices, and external environment factors to the excess expenditures, using the Blinder-Oaxaca linear decomposition technique.Methods: This study utilized a cross-sectional, retrospective study design, using data from multiple years (2006-2009) of the Medicare Current Beneficiary Survey linked with fee-for-service Medicare claims. Presence of COPD and GERD was identified using diagnoses codes. Health care expenditures consisted of inpatient, outpatient, prescription drugs, dental, medical provider, and other services. For the analysis, t-tests were used to examine unadjusted subgroup differences in average health care expenditures by the presence of GERD. Ordinary least squares regressions on log-transformed health care expenditures were conducted to estimate the excess health care expenditures associated with GERD. The Blinder-Oaxaca linear decomposition technique was used to determine the contribution of predisposing characteristics, enabling resources, need variables, personal health care practices, and external environment factors, to excess health care expenditures associated with GERD.Results: Among elderly Medicare beneficiaries with COPD, 29.3% had co-occurring GERD. Elderly Medicare beneficiaries with COPD/GERD had 1.5 times higher (24,722 [P\u3c0.001]) expenditures than did those with COPD/no GERD. Ordinary least squares regression revealed that individuals with COPD/GERD had 36.3% (P\u3c0.001) higher expenditures than did those with COPD/no GERD. Overall, 30.9% to 43.6% of the differences in average health care expenditures were explained by differences in predisposing characteristics, enabling resources, need variables, personal health care practices, and external environment factors between the two groups. Need factors explained up to 41% of the differences in average health care expenditures between the two groups.Conclusion: Among elderly Medicare beneficiaries with COPD, the presence of GERD was associated with higher expenditures. Need factors primarily contributed to the differences in average health care expenditures, suggesting that the comanagement of chronic conditions may reduce excess health care expenditures associated with GERD
Drug utilization study of off-label drug use in outpatient department of psychiatry: a prospective study at a tertiary care teaching hospital
Background: In the absence of standard psychiatric prescribing information, physician often use drugs in an off-label way. Many studies have been published across the globe reporting different rates of off-label use. There is currently no study based on Indian Drug Formulary.Methods: After taking permission from Institutional Ethics Committee (IEC), a prospective study was conducted among 285 patients attending Psychiatry outpatient department for the period of 4 months. Data related to demographic parameters, diagnosis of psychiatry conditions and drugs details were collected directly from the patient's medical records and entered in Case Record Form (CRF).The off-label drugs were categorized as per National Formulary of India. Multivariate binary logistic regression model was used to determine the predictors of off- label drug prescribing. The data were statistically analyzed using SPSS version 19 and chi-square test.Results: A total of 285 patients (169 males, 116 females) were included in the study with mean age of 36.54±13.91 years. Most of the patients (n=65, 22.8%) were diagnosed as schizophrenic. Out of 285 patients, 133(46.6%) received at least one off-label drug. A total 841 drugs were prescribed out of which 167(19.85%) were off-label. The drug most frequently prescribed as off-label were trihexiphenidyl HCL 29 (10.2%), clozapine 23 (8.1%) and clonazepam 13 (4.6%).Conclusions: Off label drugs used among psychiatry patients was 19.85%. The most frequently used off-label drugs was trihexiphenidyl HCL. The use of off-label drugs in psychiatric patients has been reportedly increasing which warrant national drug regulatory authorities to review and revise safe administration such drugs
Growth and Characterization Of Tantulam Selenide
Layered structure (lamellar) solids of transition metal dichalcogenides MX2 (M=Mo,W,Nb,Ta, X=S,Se,Te) have been extensively studied partly because of their excellent lubricating properties and partly due to their photovoltaic properties. Undo extreme pressures fluid lubricants squeeze out from between metting surfaces, causing high friction and wear. With lamellar solids such as TMDCs, shearing takes place more easily when loads are high. So, lamellar solids are well suited to extreme pressure lubrication. As a part of programme of growing than single crystals, this paper presents the growth of TaSe2. The vapour transport technique using iodine as a transporting agent and EDAX and XRD studies gives confirmation also stoichiomatric and structural properties. The type, concentration of charge carriers and also the carrier mobility has been obtained by the Hall effect measurement at room temperature
A Non - Singular Cosmological Model with Shear and Rotation
We have investigated a non-static and rotating model of the universe with an
imperfect fluid distribution. It is found that the model is free from
singularity and represents an ever expanding universe with shear and rotation
vanishing for large value of time.Comment: 10 pages, late
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