Fluctuation theorem for entropy production of a partial system in the weak coupling limit

Small systems in contact with a heat bath evolve by stochastic dynamics. Here we show that, when one such small system is weakly coupled to another one, it is possible to infer the presence of such weak coupling by observing the violation of the steady state fluctuation theorem for the partial entropy production of the observed system. We give a general mechanism due to which the violation of the fluctuation theorem can be significant, even for weak coupling. We analytically demonstrate on a realistic model system that this mechanism can be realized by applying an external random force to the system. In other words, we find a new fluctuation theorem for the entropy production of a partial system, in the limit of weak coupling.Comment: 7 pages, 3 figure

Change in Housing Structure to Cope with Natural Hazards: A Statistical Analysis from Indian Sundarban

Deltas are always being favourite destination for human due to rich biodiversity and abundant resources yet at the same time they are highly vulnerable to the impacts of natural hazards Despite their proneness to hazards coastal people make relentless efforts to cope with severe impacts through age-old indigenous knowledge and practices Dwelling structures are directly being influenced by extreme events The purpose of this study is to assess the association between natural hazards and housing pattern to combat extreme consequences in the islands of Indian Sundarban Delta ISD The western boundary of the ISD is the major focus of this study specifically Sagar Ghoramara and Mousani Islands which are prone to regular occurrence of erosion cyclone storm surges saline water inundation and flooding This study attempts to estimate the influence of particular hazard on the housing structure by means of multinomial regression using collected primary survey data from randomly selected households within these islands The result suggests that seawater ingression often collapses the mud wall of the coastal houses and houses having thatched roof are vulnerable to cyclonic storms The survey findings show that finished materials are preferable for roofs to that for wall and floor to protect houses form the cyclonic storm The result further suggests that mud is commonly used for wall and floor due to easy availability from river creeks and ponds Comparatively Sagar Island has lowest percentage of kachcha houses than other two islands which can be explained by the fact that Sagar has a better infrastructural setup Given the importance of delta regions as centre of attraction for diverse anthropocentric activities this study also tries to offer a number of concrete policy recommendations to reduce housing vulnerability from natural hazard

Neutron reactions in accreting neutron stars: a new pathway to efficient crust heating

In our calculation of neutron star crust heating we include several key new model features. In earlier work electron capture (EC) only allowed neutron emission from the daughter ground-state; here we calculate, in a deformed QRPA model, EC decay rates to all states in the daughter that are allowed by Gamow-Teller selection rules and energetics. The subsequent branching ratios between the 1n,...,xn channels and the competing $\gamma$-decay are calculated in a Hauser-Feshbach model. Since EC accesses excited states, many more neutrons are emitted in our calculation than in previous work, leading to accelerated reaction flows. In our multi-component plasma model a single (EC,xn) reaction step can produce several neutron-deficient nuclei, each of which can further decay by (EC,xn). Hence, the neutron emission occurs more continuously with increasing depth as compared to that in a one-component plasma model.Comment: Two color figures, accepted for publication by Physical Review Letter

Antitubercular specific activity of ibuprofen and the other 2-arylpropanoic acids using the HT-SPOTi whole-cell phenotypic assay

Objectives: Lead antituberculosis (anti-TB) molecules with novel mechanisms of action are urgently required to fuel the anti-TB drug discovery pipeline. The aim of this study was to validate the use of the high-throughput spot culture growth inhibition (HT-SPOTi) assay for screening libraries of compounds against Mycobacterium tuberculosis and to study the inhibitory effect of ibuprofen (IBP) and the other 2-arylpropanoic acids on the growth inhibition of M tuberculosis and other mycobacterial species. Methods: The HT-SPOTi method was validated not only with known drugs but also with a library of 47 confirmed anti-TB active compounds published in the ChEMBL database. Three over-the-counter non-steroidal anti-inflammatory drugs were also included in the screening. The 2-arylpropanoic acids, including IBP, were comprehensively evaluated against phenotypically and physiologically different strains of mycobacteria, and their cytotoxicity was determined against murine RAW264.7 macrophages. Furthermore, a comparative bioinformatic analysis was employed to propose a potential mycobacterial target. Results: IBP showed antitubercular properties while carprofen was the most potent among the 2-arylpropanoic class. A 3,5-dinitro-IBP derivative was found to be more potent than IBP but equally selective. Other synthetic derivatives of IBP were less active, and the free carboxylic acid of IBP seems to be essential for its anti-TB activity. IBP, carprofen and the 3,5-dinitro-IBP derivative exhibited activity against multidrug-resistant isolates and stationary phase bacilli. On the basis of the human targets of the 2-arylpropanoic analgesics, the protein initiation factor infB (Rv2839c) of M tuberculosis was proposed as a potential molecular target. Conclusions: The HT-SPOTi method can be employed reliably and reproducibly to screen the antimicrobial potency of different compounds. IBP demonstrated specific antitubercular activity, while carprofen was the most selective agent among the 2-arylpropanoic class. Activity against stationary phase bacilli and multidrug-resistant isolates permits us to speculate a novel mechanism of antimycobacterial action. Further medicinal chemistry and target elucidation studies could potentially lead to new therapies against TB

Matrix Metalloproteinase-1 (MMP-1) Promoter Polymorphisms are Well Linked with Lower Stomach Tumor Formation in Eastern Indian Population

Expression of matrix metalloproteinase-1 (MMP-1), an interstitial collagenase, plays a major role in cellular invasion during development of gastric cancer, a leading cause of death worldwide. A single-nucleotide polymorphism (SNP) 21607 1G/2G site of the MMP-1 gene promoter has been reported to alter transcription level. While the importance’s of other SNPs in the MMP-1 promoter have not yet been studied in gastric cancer, our aim was to investigate MMP-1 gene promoter polymorphisms and gastric cancer susceptibility in eastern Indian population. A total of 145 gastric cancer patients and 145 healthy controls were genotyped for MMP-1 21607 1G/2G (rs1799750) by PCR-restriction fragment length polymorphism (RFLP), while MMP-1 2519 A/G (rs1144393), MMP-1 2422 T/A (rs475007), MMP-1 2340 T/C (rs514921) and MMP-1 2320 T/C (rs494379) were genotyped by DNA sequencing. A positive association was found with MMP-1 2422 T/A SNP that showed significant risk for regional lymph node metastasis (P = 0.021, Odd’s ratio (OR) = 3.044, Confidence intervals (CI) = 1.187– 7.807). In addition, we found a significant association with lower stomach tumor formation among gastric cancer patients for three adjacent polymorphisms near the transcriptional start sites of [MMP-1 2422 T/A (P = 0.043, OR = 2.182, CI = 1.03– 4.643), MMP-1 2340 T/C (P = 0.075, OR = 1.97, CI = 0.94–4.158) and MMP-1 2320 T/C (P = 0.034, OR = 2.224, CI = 1.064– 40731)]. MMP-1 level in patients’ serum was correlated with MMP-1 promoter haplotypes conferring these three SNPs to evaluate the functional importance of these polymorphisms in lower stomach tumor formation and significant correlation was observed. Furthermore, MMP-1 2519 A/G polymorphism displayed poor cellular differentiation (P = 0.024, OR = 3.8, CI = 1.69–8.56) attributing a higher risk of cancer progression.In conclusion, MMP-1 proximal promoter SNPs are associated with the risk of lower stomach tumor formation and node metastasis in eastern Indian population

Heating in the Accreted Neutron Star Ocean: Implications for Superburst Ignition

We perform a self-consistent calculation of the thermal structure in the crust of a superbursting neutron star. In particular, we follow the nucleosynthetic evolution of an accreted fluid element from its deposition into the atmosphere down to a depth where the electron Fermi energy is 20 MeV. We include temperature-dependent continuum electron capture rates and realistic sources of heat loss by thermal neutrino emission from the crust and core. We show that, in contrast to previous calculations, electron captures to excited states and subsequent gamma-emission significantly reduce the local heat loss due to weak-interaction neutrinos. Depending on the initial composition these reactions release up to a factor of 10 times more heat at densities < 10^{11} g/cc than obtained previously. This heating reduces the ignition depth of superbursts. In particular, it reduces the discrepancy noted by Cumming et al. between the temperatures needed for unstable 12C ignition on timescales consistent with observations and the reduction in crust temperature from Cooper pair neutrino emission.Comment: 10 pages, 11 figures, the Astrophysical Journal, in press (scheduled for v. 662). Revised from v1 in response to referee's comment

Survey of literature on Measuring Logistics cost: A Developing Country’s Perspective

In today’s world, economic climate changes more quickly, and countries realize that globalization has made the world smaller and more competitive. Also, customers seek products and services that can respond to their specific needs and firms make effort to create competitive advantages to keep their profit and market share. All of the above trends lead firms and countries to focus on efficient logistics system. In this context, almost all developed economies and a few emerging economies estimate national logistics cost on a regular basis to understand the efficiency of their logistics system. This paper makes an attempt to survey the literature on logistics cost estimation with special emphasis from the perspective of a developing country like India where estimation is a challenge due to limitation of data