Cosmological horizon entropy and generalised second law for flat Friedmann Universe

We discuss the generalized second law (GSL) and the constraints imposed by it for two types of Friedmann universes. The first one is the Friedmann universe with radiation and a positive cosmological constant, and the second one consists of non-relativistic matter and a positive cosmological constant. The time evolution of the event horizon entropy and the entropy of the contents within the horizon are analyses in an analytical way by obtaining the Hubble parameter. It is shown that the GSL constraint the temperature of both the radiation and matter of the Friedmann universe. It is also shown that, even though the net entropy of the radiation (or matter) is decreasing at sufficiently large times as the universe expand, it exhibit an increase during the early times when universe is decelerating. That is the entropy of the radiation within the comoving volume is decreasing only when the universe has got an event horizon.Comment: 15 pages, 9 figure

Acromegaly incidentally diagnosed at term in a pregnant woman presenting with ventricular premature complexes

Pituitary adenomas lead to increased growth hormone production and acromegaly. Pregnancy in acromegaly is rare as spontaneous conception is affected. We presented a case of 31 year old lady conceived by ovulation induction and presented at term gestation with ventricular premature complexes and was subsequently diagnosed with pituitary micro adenoma causing acromegaly. There has been no reported case of pregnancy with acromegaly presenting with premature ventricular complexes. Moreover, diagnosis of acromegaly in pregnancy is difficult and limited literature is available on its effects as well as management

Detection of colistin susceptibility in extended spectrum β lactamases positive Klebsiella pneumoniae and Escherichia coli clinical isolates by broth disc elution method

Background: Antibiotic resistance is one of the greatest threats in human health. Extended spectrum β lactamases mediated resistance is prevalent worldwide, Klebsiella pneumoniae and Escherichia coli leap out as this significant ESBL producers conferring resistance to the expanded spectrum cephalosporins. Colistin is being administered as last line therapy for patients that have failed to respond to other available antibiotics that are active against Gram-negative bacteria. Methods: The present study was conducted at school of medical education Kottayam, Kerala from January 2023 to November 2023.During the period of study 150 isolates of K. pneumoniae and 136 isolates of E. coli were collected from various diagnostic microbiology laboratories in Kerala. The colistin susceptibility pattern of ESBL producing isolates was detected by broth disc elution method recommended by CLSI. Results: In this study prevalence of multi-drug resistant is 6% and 9.6% and Extensively-drug resistant is 62% and 63.9% for K. pneumoniae and E. coli respectively. ESBL production was detected as 72% in K. pneumoniae and 79% in E. coli. The colistin susceptibility pattern of ESBL producing K. pneumoniae and E. coli was detected as 76.9% and 87.9% respectively Conclusions: Our result demonstrated that the recent use of colistin as last resort treatment for extensively drug resistant gram-negative bacilli, it is essential to know the prevalence of susceptibility pattern to this antibiotic

Controllers for the Verification of Communicating Multi-Pushdown Systems

International audienceMulti-pushdowns communicating via queues are formal models of multi-threaded programs communicating via channels. They are turing powerful and much of the work on their verification has focussed on under-approximation techniques. Any error detected in the under-approximation implies an error in the system. However the successful verification of the under-approximation is not as useful if the system exhibits unverified behaviours. Our aim is to design controllers that observe/restrict the system so that it stays within the verified under-approximation. We identify some important properties that a good con- troller should satisfy. We consider an extensive under-approximation class, construct a distributed controller with the desired properties and also establish the decidability of verification problems for this class

Impact of mannitol and poly ethylene glycol 6000 induced water deficit on plant biomass and major secondary metabolites in Centella asiatica (L.) Urb. in vitro

184-191Low water potential related stresses are regulated by modifying water uptake and loss to avoid low water potential, accumulating solutes which in turn enhance active principles and its gene expressions. Present study examined effect of in vitro induced absorption of mannitol and PEG (poly ethelene glycol) 6000 in Indian pennywort, Centella asiatica (L.) Urb., neutraceutical plant, evidenced by phenotypic, molecular and phytochemical analyses. Both mannitol and PEG 6000 induce water deficit conditions in plants and retarded normal plant biomass in terms of fresh and dry weights. These effects were significantly less severe in plants subjected to mannitol, compared to PEG. PEG and mannitol imposed water deficit, resulted in decline in major active compound, asiaticoside evidenced by HPTLC of asiaticoside content. Differential expression of some selected key genes in the asiaticoside pathway including squalene synthase and β amyrin synthase by qPCR, confirmed decrease in transcript level expression of asiaticoside, whereas upregulated transcript level expression was observed in cycloartenol synthase for synthesis of phytosterols. Estimation of total flavonoids and phenolics under different water deficit conditions were found declined. In conclusion, water deficit by mannitol and PEG 6000 can significantly affects processes associated with biomass growth and ability to synthesize secondary metabolites in C. asiatica

NMR Relaxivities of Paramagnetic Lanthanide-Containing Polyoxometalates

The current trend for ultra-high-field magnetic resonance imaging (MRI) technologies opens up new routes in clinical diagnostic imaging as well as in material imaging applications. MRI selectivity is further improved by using contrast agents (CAs), which enhance the image contrast and improve specificity by the paramagnetic relaxation enhancement (PRE) mechanism. Generally, the efficacy of a CA at a given magnetic field is measured by its longitudinal and transverse relaxivities r(1) and r(2), i.e., the longitudinal and transverse relaxation rates T(1)(−1) and T(2)(−1) normalized to CA concentration. However, even though basic NMR sensitivity and resolution become better in stronger fields, r(1) of classic CA generally decreases, which often causes a reduction of the image contrast. In this regard, there is a growing interest in the development of new contrast agents that would be suitable to work at higher magnetic fields. One of the strategies to increase imaging contrast at high magnetic field is to inspect other paramagnetic ions than the commonly used Gd(III)-based CAs. For lanthanides, the magnetic moment can be higher than that of the isotropic Gd(III) ion. In addition, the symmetry of electronic ground state influences the PRE properties of a compound apart from diverse correlation times. In this work, PRE of water (1)H has been investigated over a wide range of magnetic fields for aqueous solutions of the lanthanide containing polyoxometalates [Dy(III)(H(2)O)(4)GeW(11)O(39)](5–) (Dy-W(11)), [Er(III)(H(2)O)(3)GeW(11)O(39)](5–) (Er-W(11)) and [{Er(III)(H(2)O)(CH(3)COO)(P(2)W(17)O(61))}(2)](16−) (Er(2)-W(34)) over a wide range of frequencies from 20 MHz to 1.4 GHz. Their relaxivities r(1) and r(2) increase with increasing applied fields. These results indicate that the three chosen POM systems are potential candidates for contrast agents, especially at high magnetic fields

AN EFFICIENT MULTIPROCESSOR MEMORY MANAGEMENT FRAMEWORK USING MULTI-AGENTS

ABSTRACT The current generation computer users call for fast addressal of their requests. Multi-processin

A critical review on polyvinylidene fluoride (PVDF)/zinc oxide (ZnO) based piezoelectric and triboelectric nanogenerators

In the recent era of energy crisis, piezoelectric and triboelectric effects are surfacing out of several research topics. Polyvinylidene fluoride (PVDF) and its copolymers are well known piezoelectric polymers due to their high piezoelectricity and widely used in flexible devices. PVDF is greatly utilized in preparation of triboelectric layer also due to its higher electronegative nature amongst common polymers. On the other hand, zinc oxide (ZnO) has been studied widely to investigate its multifunctional properties including piezoelectricity, pyroelectricity and antibacterial activity. This versatile material can be prepared, using low cost and environmental friendly routes, in various morphologies. Various research is already performed to capture the synergistic effect of reinforcing ZnO within PVDF polymeric matrix. This work firstly describes the basic principles of piezoelectric and triboelectric effects. Thereafter, piezoelectric and triboelectric performances of PVDF and ZnO based materials are briefly depicted based on their structures. Finally, challenges and future scopes, associated with the mechanical energy harvesting from such materials, are highlighted

The Homeobox Protein CEH-23 Mediates Prolonged Longevity in Response to Impaired Mitochondrial Electron Transport Chain in C. elegans

Recent findings indicate that perturbations of the mitochondrial electron transport chain (METC) can cause extended longevity in evolutionarily diverse organisms. To uncover the molecular basis of how altered METC increases lifespan in C. elegans, we performed an RNAi screen and revealed that three predicted transcription factors are specifically required for the extended longevity of mitochondrial mutants. In particular, we demonstrated that the nuclear homeobox protein CEH-23 uniquely mediates the longevity but not the slow development, reduced brood size, or resistance to oxidative stress associated with mitochondrial mutations. Furthermore, we showed that ceh-23 expression levels are responsive to altered METC, and enforced overexpression of ceh-23 is sufficient to extend lifespan in wild-type background. Our data point to mitochondria-to-nucleus communications to be key for longevity determination and highlight CEH-23 as a novel longevity factor capable of responding to mitochondrial perturbations. These findings provide a new paradigm for how mitochondria impact aging and age-dependent diseases