York University

About: York University is a education organization based out in Toronto, Ontario, Canada. It is known for research contribution in the topics: Population & Politics. The organization has 18899 authors who have published 43357 publications receiving 1568560 citations.

Dating Experiences of Bullies in Early Adolescence

Abstract: In this study, 196 young adolescents who reported that they bullied their peers were identified out of a sample of 1,758 students in Grades 5 through 8. After selecting from the total sample a grou...

Evidence for HCO3− Transport by the Blue-Green Alga (Cyanobacterium) Coccochloris peniocystis

Abstract: The possibility of HCO 3 − transport in the blue-green alga (cyanobacterium) Coccochloris peniocystis has been investigated. Coccochloris photosynthesized most rapidly in the pH range 8 to 10, where most of the inorganic C exists as HCO 3 − . If photosynthesis used only CO 2 from the external solution the rate of photosynthesis would be limited by the rate of HCO 3 − dehydration to CO 2 . Observed rates of photosynthesis at alkaline pH were as much as 48-fold higher than could be supported by spontaneous dehydration of HCO 3 − in the external solution. Assays for extracellular carbonic anhydrase were negative. The evidence strongly suggests that HCO 3 − was a direct C source for photosynthesis. Weakly buffered solutions became alkaline during photosynthesis with a one-to-one stoichiometry between OH − appearance in the medium and HCO 3 − initially added. Alkalization occurred only during photosynthesis and was blocked by 3-(3,4-dichlorophenyl)-1, 1-dimethylurea, diuron. It is suggested that HCO 3 − was transported into cells of Coccochloris in exchange for OH − produced as a result of HCO 3 − fixation in photosynthesis. The inorganic C concentration required to support a rate of photosynthesis of half the maximum rate ( K m ) was 6 micromolar at pH 8.0 or, in terms of available CO 2 , a K m of 0.16 micromolar. This value is two orders of magnitude lower than reported K m values for the d-ribulose-1,5-bisphosphate carboxylase for blue-green algae. It is suggested that the putative HCO 3 − transport by Coccochloris serves to raise the CO 2 concentration around the carboxylase to levels high enough for effective fixation.

Nutritional Treatment for Acquired Immunodeficiency Virus-Associated Wasting Using β-Hydroxy β-Methylbutyrate, Glutamine, and Arginine: A Randomized, Double-Blind, Placebo-Controlled Study

Abstract: Background: The current study was designed to examine whether a combination of three nutrients, consisting of β-hydroxy-β-methylbutyrate (HMB), a metabolite of leucine, L-glutamine (Gln) and L-arginine (Arg), each of which has been previously shown to slow muscle proteolysis, could synergistically alter the course of muscle wasting in patients with established acquired immunodeficiency syndrome (AIDS). Methods: Sixty-eight human immunodeficiency virus (HIV)-infected patients with a documented weight loss of at least 5% in the previous 3 months were recruited from the HIV clinic at Nassau County Medical Center. The subjects were randomly assigned in a double-blind fashion to receive either placebo containing maltodextrin or the nutrient mixture (HMB/Arg/Gln) containing 3 g HMB, 14 g L-glutamine, and 14 g L-arginine given in two divided doses daily for 8 weeks. Body weights (BW) were recorded weekly and lean body mass (LBM) and fat mass (FM) were measured by air displacement plethysmography and by a single ...

Effectiveness of Acute Geriatric Unit Care Using Acute Care for Elders Components: A Systematic Review and Meta-Analysis

Abstract: Adults aged 65 and older constitute the “core business” of hospitals.1 Although they represent 13% of the population in the United States2 and 14% of the population in Canada,3 older adults account for 43% of inpatient hospital days in the United States4 and 40% in Canada.5 This trend is likely to continue given population aging.3 During hospitalization for an acute event such as illness or injury, older adults are at risk of experiencing functional decline and iatrogenic complications, including falls, pressure ulcers, and delirium, which further contribute to functional decline.6 Hospital-acquired functional decline is associated with greater hospital expenditures, institutionalization, and mortality in older adults7 even after controlling for comorbidity and illness severity.8 Therefore, early intervention (before an acute episode is resolved) is critical because of the short length of time during which older persons can recover functional losses, resume their former lives, and avoid institutionalization.9 Dedicated geriatric units, based on a prehabilitation10 and function-focused11 model of care called Acute Care for Elders (ACE), have been designed specifically to prevent functional decline and related complications in older adults admitted to the hospital for an acute event.12,13 In response to an increasingly older and complex hospital population, some service providers have adopted the ACE model on hospital units where older adults are admitted.13 However, the overall effect of acute geriatric unit care, based on all or part of the ACE model and introduced during the acute phase of illness or injury, is unclear and unquantified. Two systematic reviews of acute geriatric unit care based on the ACE model have been conducted,14,15 but the authors did not present results of meta-analyses, supporting the need for this current review. Three prior reviews combined data from studies conducted with individuals in the acute and subacute illness phases;14,16,17 the results have limited validity for individuals in the acute phase of an illness or injury. One meta-analysis18 imputed means for missing standard deviations for cost and length-of-stay outcomes in almost 30% of included studies,18 which may have resulted in an underestimation of the overall effect. Last, no meta-analysis of acute geriatric unit care included iatrogenic complications, which are critical indicators of quality hospital care.19 The purpose of this study was to determine the effectiveness of acute geriatric unit care, based on all or part of the ACE model components and introduced in the acute phase of illness or injury, in reducing iatrogenic complications, functional decline, length of hospital stay, poor discharge destination outcomes, mortality, costs, and hospital readmissions in older adults.