A preliminary list of the bibionidae of British Columbia and some locality records

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From the ISR to RHIC--measurements of hard-scattering and jets using inclusive single particle production and 2-particle correlations

Hard scattering in p-p collisions, discovered at the CERN ISR in 1972 by the method of leading particles, proved that the partons of Deeply Inelastic Scattering strongly interacted with each other. Further ISR measurements utilizing inclusive single or pairs of hadrons established that high pT particles are produced from states with two roughly back-to-back jets which are the result of scattering of constituents of the nucleons as desribed by Quantum Chromodynamics (QCD), which was developed during the course of these measurements. These techniques, which are the only practical method to study hard-scattering and jet phenomena in Au+Au central collisions at RHIC energies, are reviewed, as an introduction to present RHIC measurements.Comment: To appear in the proceedings of the workshop on Correlations and Fluctuations in Relativistic Nuclear Collisions, MIT, Cambridge, MA, April 21-23, 2005, 10 pages, 9 figures, Journal of Physics: Conference Proceeding

Transverse Energy Measurement in Au+Au Collisions by the STAR Experiment

Transverse energy ($E_T$) has been measured with both of its components, namely hadronic ($E_T^{had}$) and electromagnetic ($E_T^{em}$) in a common phase space at mid-rapidity for 62.4 GeV Au+Au collisions by the STAR experiment. $E_T$ production with centrality and $\sqrt{s_{NN}}$ is studied with similar measurements from SPS to RHIC and is compared with a final state gluon saturation model (EKRT). The most striking feature is the observation of a nearly constant value of $E_T/N_{ch} \sim 0.8$ GeV from AGS, SPS to RHIC. The initial energy density estimated by the boost-invariant Bjorken hydrodynamic model, is well above the critical density for a deconfined matter of quarks and gluons predicted by lattice QCD calculations.Comment: 4 pages, 10 figures, Presented in Quark Matter 2008, Jaipur, India. To be published in Indian Journal of Physic

Global modeling of secondary organic aerosol formation from aromatic hydrocarbons: high- vs low-yield pathways

Formation of SOA from the aromatic species toluene, xylene, and, for the first time, benzene, is added to a global chemical transport model. A simple mechanism is presented that accounts for competition between low and high-yield pathways of SOA formation, wherein secondary gas-phase products react further with either nitrogen oxide (NO) or hydroperoxy radical (HO2) to yield semi- or non-volatile products, respectively. Aromatic species yield more SOA when they react with OH in regions where the [NO]/[HO2] ratios are lower. The SOA yield thus depends upon the distribution of aromatic emissions, with biomass burning emissions being in areas with lower [NO]/[HO2] ratios, and the reactivity of the aromatic with respect to OH, as a lower initial reactivity allows transport away from industrial source regions, where [NO]/[HO2] ratios are higher, to more remote regions, where this ratio is lower and, hence, the ultimate yield of SOA is higher. As a result, benzene is estimated to be the most important aromatic species with regards to formation of SOA, with a total production nearly equal that of toluene and xylene combined. In total, while only 39% percent of the aromatic species react via the low-NOx pathway, 72% of the aromatic SOA is formed via this mechanism. Predicted SOA concentrations from aromatics in the Eastern United States and Eastern Europe are actually largest during the summer, when the [NO]/[HO2] ratio is lower. Global production of SOA from aromatic sources is estimated at 3.5 Tg/yr, resulting in a global burden of 0.08 Tg, twice as large as previous estimates. The contribution of these largely anthropogenic sources to global SOA is still small relative to biogenic sources, which are estimated to comprise 90% of the global SOA burden, about half of which comes from isoprene. Compared to recent observations, it would appear there are additional pathways beyond those accounted for here for production of anthropogenic SOA. However, owing to differences in spatial distributions of sources and seasons of peak production, there are still regions in which aromatic SOA produced via the mechanisms identified here are predicted to contribute substantially to, and even dominate, the local SOA concentrations, such as outflow regions from North America and South East Asia during the wintertime, though total SOA concentrations there are small (~0.1 μg/m^³)

Anisotropic magnetoresistance in nanocontacts

We present ab initio calculations of the evolution of anisotropic magnetoresistance (AMR) in Ni nanocontacts from the ballistic to the tunnel regime. We find an extraordinary enhancement of AMR, compared to bulk, in two scenarios. In systems without localized states, like chemically pure break junctions, large AMR only occurs if the orbital polarization of the current is large, regardless of the anisotropy of the density of states. In systems that display localized states close to the Fermi energy, like a single electron transistor with ferromagnetic electrodes, large AMR is related to the variation of the Fermi energy as a function of the magnetization direction.Comment: 7 pages, 4 figures; revised for publication, new figures in greyscal

Non-descent vaginal hysterectomy in previous cesarean section: a retrospective study

Background: Non-descent vaginal hysterectomy (NDVH) is removal of uterus through vagina in non-prolapsed uterus. As there is an increase in caesarean section, hysterectomy in women with previous caesarean section is also increasing. The objective of this study is to assess the feasibility and safety of non-descent vaginal hysterectomy in patients with previous caesarean section.Methods: This is a retrospective study conducted in the department of obstetrics and gynecology, Government Medical College, Thrissur from January 2017 to December 2018. Non-descent vaginal hysterectomy in 24women with previous caesarean section was studied. Details regarding age, parity, number of caesarean sections, indication of surgery, intraoperative and postoperative complications were evaluated.Results: All 24 women underwent non-descent vaginal hysterectomy successfully. 10 women (41.7%) were between 46-49 years. Commonest indication of hysterectomy was fibroid uterus (41.7%) and most common complaint was heavy menstrual bleeding (79%). There was bladder injury in one woman with history of previous 2 caesarean section. 3 women developed UTI in postoperative period.Conclusions: Vaginal hysterectomy is associated with lower complications and more rapid recovery. A successful NDVH in previous caesarean section depends on the expertise and experience of the surgeon. NDVH in previous caesarean is safe in expert hands

Astronomy in the Cloud: Using MapReduce for Image Coaddition

In the coming decade, astronomical surveys of the sky will generate tens of terabytes of images and detect hundreds of millions of sources every night. The study of these sources will involve computation challenges such as anomaly detection and classification, and moving object tracking. Since such studies benefit from the highest quality data, methods such as image coaddition (stacking) will be a critical preprocessing step prior to scientific investigation. With a requirement that these images be analyzed on a nightly basis to identify moving sources or transient objects, these data streams present many computational challenges. Given the quantity of data involved, the computational load of these problems can only be addressed by distributing the workload over a large number of nodes. However, the high data throughput demanded by these applications may present scalability challenges for certain storage architectures. One scalable data-processing method that has emerged in recent years is MapReduce, and in this paper we focus on its popular open-source implementation called Hadoop. In the Hadoop framework, the data is partitioned among storage attached directly to worker nodes, and the processing workload is scheduled in parallel on the nodes that contain the required input data. A further motivation for using Hadoop is that it allows us to exploit cloud computing resources, e.g., Amazon's EC2. We report on our experience implementing a scalable image-processing pipeline for the SDSS imaging database using Hadoop. This multi-terabyte imaging dataset provides a good testbed for algorithm development since its scope and structure approximate future surveys. First, we describe MapReduce and how we adapted image coaddition to the MapReduce framework. Then we describe a number of optimizations to our basic approach and report experimental results comparing their performance.Comment: 31 pages, 11 figures, 2 table

TMC (Thrissur Medical College) modified Robson criteria for caesarean sections

Background: The Robson system is the most widely accepted classification system available for analysing characteristics of delivering women worldwide. Several authors have tried modifications in the existing system. The objective of this study was to modify the existing system with relevance to caesarean section rates in various obstetric population and to identify major factors contributing to it.Methods: This study was performed in Government Medical College, Thrissur from January 2017 to June 2017. All women delivered during this period were classified according to the modified system consisting of 8 groups using their maternal characteristics and obstetric history. Each major group were sub classified into 3: women who went into spontaneous labour/ induced labour/ CS done before labour. For each group, we calculated the contribution to overall CS and Primary CS separately. Women with Previous CS were analyzed as a separate group. This classification was intended to directly estimate primary as well as repeat CS rates and indirectly the VBAC rates. Results: Out of total 1337 women delivered, 413 underwent CS (30.8%). The contribution made by previous CS group to overall CS was 61.5%, and the repeat section rate was 91.3%. The primary CS rate was 15% and the maximum contribution was made by term induced primigravida followed by Primigravida with Breech presentation. VBAC rate was 8.6%.Conclusions: Our modified Robson system can be effectively utilized in analysing delivering women and provide valuable information regarding the delivery characteristics with particular relevance to Caesarean sections