3,637 research outputs found

    Optimization of Analytic Window Functions

    Full text link
    Analytic functions represent the state-of-the-art way of performing complex data analysis within a single SQL statement. In particular, an important class of analytic functions that has been frequently used in commercial systems to support OLAP and decision support applications is the class of window functions. A window function returns for each input tuple a value derived from applying a function over a window of neighboring tuples. However, existing window function evaluation approaches are based on a naive sorting scheme. In this paper, we study the problem of optimizing the evaluation of window functions. We propose several efficient techniques, and identify optimization opportunities that allow us to optimize the evaluation of a set of window functions. We have integrated our scheme into PostgreSQL. Our comprehensive experimental study on the TPC-DS datasets as well as synthetic datasets and queries demonstrate significant speedup over existing approaches.Comment: VLDB201

    Which Osteotomy for Osteonecrosis of the Femoral Head and Which Patient for the Osteotomy?

    Get PDF
    Transtrochanteric curved varus osteotomy (TCVO) and transtrochanteric rotational osteotomy (TRO) are joint-preserving procedures for osteonecrosis of the femoral head. The purpose of this review is to provide up-to-date guidelines for the osteotomies. One retrospective comparison revealed that TCVO has shorter operation time, less bleeding, lower incidence of osteophyte formation, and lower rate of secondary collapse. To obtain successful results of the osteotomy, the patient should be younger than 40 years and should have a body mass index of less than 24 kg/m2. The osteotomy should be performed in early stages of femoral head osteonecrosis before marked collapse of the femoral head. The patient should have a medium-size lesion and an enough viable bone to restore the intact articular surface and subchondral bone in the weight-bearing area

    Medication use by early-stage breast cancer survivors: a 1-year longitudinal study.

    Get PDF
    PurposeThe aim of this study is to characterize the patterns of medication use by early-stage breast cancer (ESBC) survivors from diagnosis to 1 year post-chemotherapy.MethodsA single-center longitudinal study was conducted with ESBC patients diagnosed between December 2011 and June 2014. Data on the medication use of individual patients were retrieved from prescription databases, supplemented by records from the National Electronic Health Records. The data covered the period from ESBC diagnosis to 1 year post-chemotherapy. Medication types were classified according to the World Health Organization's Anatomical Therapeutic Chemical classification system, and medication for chronic diseases was created by adapting a list of 20 chronic diseases provided by the U.S. Department of Human and Health Services.ResultsOf the 107 patients involved in the study (mean age 51.1 ± 8.4 years; 78.5 % Chinese), 46.7 % manifested non-cancer comorbidities, of which hypertension (24.3 %) was the most prevalent, followed by hyperlipidemia (13.1 %) and diabetes (5.6 %). Calcium channel blockers (12.1 %) and lipid-modifying agents (11.2 %) were the most common chronic medication types used before chemotherapy, and their use persisted during chemotherapy (10.3 and 11.2 %, respectively) and after chemotherapy (11.2 and 13.1 %, respectively). Hormonal therapy was the predominant post-chemotherapy medication (77.6 %). A statistically significant increase (p < 0.0001) was observed in the mean number of chronic disease medication classes prescribed to patients between the pre-chemotherapy (0.53 ± 1.04) and chemotherapy (0.62 ± 1.08) periods and between the chemotherapy and post-chemotherapy (1.63 ± 1.35) periods.ConclusionsThere is an increase in trend of chronic medication usage in breast cancer survivors after cancer treatment. This study provides important insights into the design of medication management programs tailored to this population. Future studies should incorporate a control population to improve the interpretation of study results

    Design of Embedded System for Grid Handtop Computing(ESGHC)

    Get PDF
    ESGHC applies the grid computing technology which is built under a grid environmentfor handtop devices. By having ESGHC, sharing of handtop devices in terms of computational power and storage are virtually possible

    Various temperature effects on spikelet growth in hulless oat during grain-filling stage

    Get PDF
    Temperature conditions affect growth and grain development during the grain-filling stage, but a comprehensive analysis of oat subjected to different temperatures during grain development has not been studied. In this study, an integrated physiological and proteomic examination of oat spikelets was performed to analyze the influence of five different day-time temperatures on stress-relative parameters and grain development. Physiological analysis showed decrease of total chlorophyll, shoot dry weight and spikelet shape development and increased activation of MDA, soluble sugar and antioxidant enzymes, with increase of temperatures. However, considering major grain yield components and storage materials, there should be an optimum temperature during ripening period. The result of proteomic analysis showed significantly high expressions of stress-related gene in high temperature treatment and grain storage materials in optimum temperature. Our findings indicate that temperature conditions during the grain-filling period exert a major influence on yield potential

    Total Laparoscopic Hysterectomy and Laparoscopy-Assisted Vaginal Hysterectomy

    Get PDF
    This study suggests that total laparoscopic hysterectomy and laparoscopic-assisted vaginal hysterectomy are safe and feasible with laparoscopic-assisted hysterectomy preferred in patients with a mass involving the lower uterine segment or those with a large uterus
    corecore