Neutrinos from type Ia supernovae: the deflagration-to-detonation transition scenario

It has long been recognized that the neutrinos detected from the next core-collapse supernova in the Galaxy have the potential to reveal important information about the dynamics of the explosion and the nucleosynthesis conditions as well as allowing us to probe the properties of the neutrino itself. The neutrinos emitted from thermonuclear - type Ia - supernovae also possess the same potential, although these supernovae are dimmer neutrino sources. For the first time, we calculate the time, energy, line of sight, and neutrino-flavor-dependent features of the neutrino signal expected from a three-dimensional delayed-detonation explosion simulation, where a deflagration-to-detonation transition triggers the complete disruption of a near-Chandrasekhar mass carbon-oxygen white dwarf. We also calculate the neutrino flavor evolution along eight lines of sight through the simulation as a function of time and energy using an exact three-flavor transformation code. We identify a characteristic spectral peak at $\sim 10$ MeV as a signature of electron captures on copper. This peak is a potentially distinguishing feature of explosion models since it reflects the nucleosynthesis conditions early in the explosion. We simulate the event rates in the Super-K, Hyper-K, JUNO, and DUNE neutrino detectors with the SNOwGLoBES event rate calculation software and also compute the IceCube signal. Hyper-K will be able to detect neutrinos from our model out to a distance of $\sim 10$ kpc. At 1 kpc, JUNO, Super-K, and DUNE would register a few events while IceCube and Hyper-K would register several tens of events.Comment: 44 pages, 29 figures & 2 tables. Updated to match Phys. Rev. D version, including a new event channel discussion and improved IceCube result

Solution phase synthesis of alamethicin I

The total synthesis of alamethicin I by solution phase methods is reported

Racemization at proline residues during peptide bond formation : a study of diastereomeric mixtures of synthetic alamethicin fragments by 270 MHz <SUP>1</SUP>H NMR

The stepwise synthesis of amino terminal pentapeptide of alamethicin, Z-Aib-Pro-Aib-Ala-Aib-OMe, by the dicyclohexylcarbodiimide mediated couplings leads to extensive racemization at the Ala and Pro residues. Racemization is largely suppressed by the use of additives like N-hydroxysuccinimide and 1-hydroxybenzotriazole. The presence of diastereomeric peptides may be detected by the observation of additional methyl ester and benzylic methylene signals in the 270 MHz 1H NMR spectra. Unambiguous spectral assignment of the signals to the diastereomers has been carried out by the synthesis and NMR studies of the D-Ala tetra and pentapeptides. The racemization at Pro is of particular relevance in view of the reported lack of inversion at C-terminal Pro on carboxyl activation

An analysis of software aging in cloud environment

Cloud Computing is the environment in which several virtual machines (VM) run concurrently on physical machines. The cloud computing infrastructure hosts multiple cloud service segments that communicate with each other using the interfaces. This creates distributed computing environment. During operation, the software systems accumulate errors or garbage that leads to system failure and other hazardous consequences. This status is called software aging. Software aging happens because of memory fragmentation, resource consumption in large scale and accumulation of numerical error. Software aging degrads the performance that may result in system failure. This happens because of premature resource exhaustion. This issue cannot be determined during software testing phase because of the dynamic nature of operation. The errors that cause software aging are of special types. These errors do not disturb the software functionality but target the response time and its environment. This issue is to be resolved only during run time as it occurs because of the dynamic nature of the problem. To alleviate the impact of software aging, software rejuvenation technique is being used. Rejuvenation process reboots the system or re-initiates the softwares. This avoids faults or failure. Software rejuvenation removes accumulated error conditions, frees up deadlocks and defragments operating system resources like memory. Hence, it avoids future failures of system that may happen due to software aging. As service availability is crucial, software rejuvenation is to be carried out at defined schedules without disrupting the service. The presence of Software rejuvenation techniques can make software systems more trustworthy. Software designers are using this concept to improve the quality and reliability of the software. Software aging and rejuvenation has generated a lot of research interest in recent years. This work reviews some of the research works related to detection of software aging and identifies research gaps

Elastic-plastic fracture analysis of anisotropy effect on AA2050-T84 alloy at different temperatures: A Numerical Study

The third generation Al-Li alloy AA2050-T84 is widely used in aircraft applications due to its lightweight and significant mechanical properties. The anisotropic variations of tensile and compression properties of this alloy at various temperatures are substantial. In this work, the variations of the J-integral, CTOD, and Plastic Zone Size (PZS) due to anisotropy of a 4-inch thick AA2050-T84 plate at ambient and cryogenic temperatures were studied numerically by using Compact Tension (C(T)) specimen. The material anisotropy resulted in fracture and constraint parameter variation for Mode-I constant load. Numerical results indicated a decrease in crack driving forces and a constraint parameter with the decrease in temperature at the plate surface and central location. Plate surface locations appear to be isotropic for both temperatures under elastic-plastic fracture analyses as crack driving forces were almost identical. The temperature effect is more on constraint as the normalized PZS values at ambient temperature have been twice that of cryogenic temperature. The isotropic behavior of a plate under sub-zero temperature makes the plate suitable for cryogenic temperature applications

Biodiversity of fresh water algae from Guindy campus of Chennai, India

The present work deals with the 35 fresh water algal samples and description of 62 taxa of biodiversity of fresh water algae from University of Madras Guindy campus of Chennai. Collections of 35 fresh water algal samples were carried out during the month of December 2010 to April 2011. Samples were examined in the laboratory and identified. The following algae were present Chlorococcum(1), Elakatothrix (1), Chlorella (1), Palmellococcus (1), Tetraedron  (1), Polyedriopsis (1), Chodatella (1), Oocystis (2),  Coelastrum (1), Scenedesmus quadricauda  (Turpin) Breb. var. longispina  (Chodat) G. M. Smith, Scenedesmus (3), Microspora (1), Rhizoclonium (1), Trentipholia  (2), Closterium (1), Cosmarium (5) of Chlorophyceae, Cyclotella (1),  Fragilaria (2),  Achnanthes (1), Amphora (1), Navicula (5), Pinnularia (1), Hantzschia  (1) and Nitzschia (1) of Bacillariophyceae and Microcystis (1), Chroococcus (3)  Chroococcidiopsis (1), Gloeocapsa (2), Gleocapsopsis (1), Aphanotheace (1), Chlorogloea (2), Oscillatoria (3), Phormidium (3), Lyngbya (3), Microcoleus (1), Microchaete tenera (1), Calothrix (1), Camptylonema (1)  and Hapalosiphon (1) of Cyanophyceae were recorded. Algae are described with photographs

Investigation on Geosynthetic Reinforced Two Layered Soil System

Use of geosynthetics for flexible pavements founded on expansive soil subgrade is one of feasible and economic solution to minimize the undulation and required pavement thickness. In this present investigation the effect of inclusion of the geosynthetic reinforcement on California Bearing Ratio (CBR) value of a two layered soil system with black cotton soil at bottom and granular soil at top as a buffer layer, with different thickness configuration and geotextiles of different physical and mechanical properties was studied by laboratory and field California bearing ratio tests. Thickness of flexible pavement over the two layer soil system of different thickness configurations was estimated for unreinforced and reinforced two layered soil system by the method suggested by United States Army Corps of Engineers and Indian Road Congress. The reduction (%) in the thickness of pavement due to inclusion of geotextiles has been observed in the investigation. The reduction in thickness of pavement can be achieved up to 53.53% depending upon the thickness configuration and the type of the geotextile used. The results have shown that the field CBR tests can yield the results in conformity with the values obtained in the laboratory test

Life style Medicine to improve Physical and Psychological well-being

The brain does not work in a fixed state and it has no fixed memory or intelligence that is present from birth. It is in a constant state of fluctuation.The positives and negatives can be clearly determined regarding a situation with increased insight when our mind is at peace. One of the probable reasons for the increase in cognitive disorders is extreme pressure, stress or shock.In this article, we bring about the effective and scientifically proven methodologies with which the physical and psychological well-being can be improved. This not only brings about betterment within ourselves but also directs our personal and professional life towards achieving the goals as per our wishes. &nbsp