504 research outputs found
Brome grass population dynamics
To identify the level of brome grass under various crop rotation systems. To design the best control system. To understand some of the effects of changing rotation systems. 86C
Gait and Force Analysis of Provoked Pig Gait on Clean and Fouled Concrete Surfaces
Gait and force analysis have proven to be useful methods in linking claw injuries to surface material conditions. To determine the relationship between claw disorder and floor properties such as friction and surface abrasiveness, the factors controlling gait must be characterised. The effects of fouled concrete floor conditions on the gait of 10 pigs walking in a curve, using kinematics and kinetics to record gait parameters and slip frequency are described and compared with clean conditions. Pigs adapted to fouled floor conditions by reducing their walking speed and stride length, using a higher number of 3-foot support phases and by lowering diagonality. This adaption produced lower vertical forces, a twofold reduction in propulsion and outward stabilisation force and a threefold increase in braking force, without reducing the peak utilised coefficient of friction (UCOF). The UCOF values for both limbs of the curve walking pigs exceeded the recorded dynamic coefficient of friction and the corresponding UCOF values for pigs walking a straight line in fouled floor condition. As UCOF increased and available friction from the fouled floor surface decreased, this resulted in higher forward and backward slip frequency in both limbs for pigs walking in a curve. Pigs provoked to walk in a curve can adapt to fouled floor condition, but if the floor is heavily fouled this adaption is not sufficient to ensure safe walking
Rodents as receptor species at a tritium
New methods are being employed on the Department of Energy’s Savannah River Site to deal with the disposal of tritium, including the irrigation of a hardwood/pine forest with tritiated water from an intercepted contaminant plume to reduce concentrations of tritium outcropping into Fourmile Branch, a tributary of the Savannah River. The use of this system has proven to be an effective means of tritium disposal. To evaluate the impact of this activity on terrestrial biota, rodent species were captured on the tritium disposal site and a control site during two trapping seasons in order to assess tritium exposure resulting from the forest irrigation. Control site mice had background levels of tritium, 0.02 Bq/mL, with disposal site mice having significantly higher tritium concentrations, meanZ34.86 Bq/mL. Whole body tritium concentrations of the mice captured at the disposal site were positively correlated with tritium application and negatively correlated with precipitation at the site
Recording advances for neural prosthetics
An important challenge for neural prosthetics research is to record from populations of neurons over long periods of time, ideally for the lifetime of the patient. Two new advances toward this goal are described, the use of local field potentials (LFPs) and autonomously positioned recording electrodes. LFPs are the composite extracellular potential field from several hundreds of neurons around the electrode tip. LFP recordings can be maintained for longer periods of time than single cell recordings. We find that similar information can be decoded from LFP and spike recordings, with better performance for state decodes with LFPs and, depending on the area, equivalent or slightly less than equivalent performance for signaling the direction of planned movements. Movable electrodes in microdrives can be adjusted in the tissue to optimize recordings, but their movements must be automated to be a practical benefit to patients. We have developed automation algorithms and a meso-scale autonomous electrode testbed, and demonstrated that this system can autonomously isolate and maintain the recorded signal quality of single cells in the cortex of awake, behaving monkeys. These two advances show promise for developing very long term recording for neural prosthetic applications
Cytosolic ferritin and lipid-associated ferritin are metabolically different in guinea-pig livers
Second-Hand Tobacco Smoke in Never Smokers Is a Significant Risk Factor for Coronary Artery Calcification
ObjectivesThe aim of this study was to assess the relationship of the extent of subclinical atherosclerosis measured by coronary artery calcification (CAC) to the extent of second-hand tobacco smoke (SHTS) exposure in asymptomatic people who never smoked.BackgroundAn association between SHTS and CAC was recently reported in a single study, but the quantitative aspects of the relationship are not known.MethodsA cohort of 3,098 never smokers 40 to 80 years of age, enrolled in the FAMRI-IELCAP (Flight Attendant Medical Research Institute International Early Lung Cancer Action Program) screening program, completed a SHTS questionnaire, and had a low-dose nongated computed tomography scan. The questionnaire provided a quantitative score for total SHTS exposure, as well as separately as a child and as an adult at home and at work; 4 categories of exposure to SHTS were identified (minimal, low, moderate, and high exposure). CAC was graded using a previously validated ordinal scale score that ranged from 0 to 12. Logistic regression analysis of the prevalence and ordered logistic regression analysis of the extent of CAC were performed to assess the independent contribution of SHTS adjusted for age, sex, diabetes, hypercholesterolemia, hypertension, and renal disease. Linear and quadratic regression analyses of CAC and SHTS were performed.ResultsThe prevalence of CAC was 24.3% (n = 754) and was significantly higher in those with more than minimal SHTS exposure compared with those with minimal SHTS exposure (26.4% vs. 18.5%, p < 0.0001). The adjusted odds ratios for CAC prevalence were 1.54 (95% confidence interval: 1.17 to 2.20) for low SHTS exposure, 1.60 (95% confidence interval: 1.21 to 2.10) for moderate exposure, and 1.93 (95% confidence interval: 1.49 to 2.51) for high exposure. The association of the extent of SHTS with the extent of CAC was confirmed by the adjusted odds ratio (p < 0.0001).ConclusionsThe presence and extent of CAC were associated with extent of SHTS exposure even when adjusted for other risk factors for CAC, suggesting that SHTS exposure causes CAC
Determinants of knowledge management systems success in the banking industry
Purpose – This study aims to examine the impact from technical and social aspects on knowledge management system (KMS) success. Moreover, this study also attempts to examine the interrelationships between KMS success and user satisfaction. Design/methodology/approach – A questionnaire survey was used to collect data from the commercial bank officers to test the proposed KMS success model. All the measurement scales adopted in this study were adopted from the existing literature. The data collected in this study were analysed using both SPSS and structural equation modelling approach via AMOS. Findings – The research results indicate that both technical (knowledge quality, system quality and service quality) and social factors (user trust and management support) play a significant and positive role in system user satisfaction. The results also show that user satisfaction have a direct influence on the success of KMS and vice versa. Originality/value – This study is one of the few studies on KMS which include both the technical and social perspectives in examining KMS success. This research study raises the importance of social factors, which have been earlier neglected by many studies on KMS success models. Moreover, the interrelationships relationship between KMS success and user satisfaction also been examined in this study
Yellow fever in the Gambia, 1978-1979 : epidemiologic aspects with observations on the occurrence of orungo virus infections
Exchange bias between van der Waals materials: tilted magnetic states and field-free spin-orbit-torque switching
Magnetic van der Waals heterostructures provide a unique platform to study
magnetism and spintronics device concepts in the two-dimensional limit. Here,
we report studies of exchange bias from the van der Waals antiferromagnet CrSBr
acting on the van der Waals ferromagnet Fe3GeTe2 (FGT). The orientation of the
exchange bias is along the in-plane easy axis of CrSBr, perpendicular to the
out-of-plane anisotropy of the FGT, inducing a strongly tilted magnetic
configuration in the FGT. Furthermore, the in-plane exchange bias provides
sufficient symmetry breaking to allow deterministic spin-orbit torque switching
of the FGT in CrSBr/FGT/Pt samples at zero applied magnetic field. A minimum
thickness of the CrSBr greater than 10 nm is needed to provide a non-zero
exchange bias at 30 K
Priority Medicines for Maternal and Child Health: A Global Survey of National Essential Medicines Lists
BACKGROUND: In April 2011, the World Health Organization (WHO) published a list of "priority medicines" for maternal and child health based on 1) the global burden of disease and 2) evidence of efficacy and safety. The objective of this study was to examine the occurrence of these priority medicines on national essential medicines lists. METHODS AND FINDINGS: All essential medicines lists published since 1999 were selected from the WHO website collection. The most-up-to date list for each country was then selected, resulting in 89 unique country lists. Each list was evaluated for inclusion of medicines (chemical entity, concentration, and dosage form) on the Priority Medicines List. There was global variation in the listing of the Priority Medicines. The most frequently listed medicine was paracetamol, on 94% (84/89) of lists. Sodium chloride, gentamicin and oral rehydration solution were on 93% (83/89) of lists. The least frequently listed medicine was the children's antimalarial rectal artesunate, on 8% of lists (7/89); artesunate injection was on 16% (14/89) of lists. Pediatric artemisinin combination therapy, as dispersible tablets or flexible oral solid dosage form, appeared on 36% (32/89) of lists. Procaine benzylpenicillin, for treatment of pediatric pneumonia and neonatal sepsis, was on 50% (45/89) of the lists. Zinc, for treatment of diarrhoea in children, was included on only 15% (13/89) of lists. For prevention and treatment of postpartum hemorrhage in women, oxytocin was more prevalent on the lists than misoprostol; they were included on 55 (62%) and 31 (35%) of lists, respectively. Cefixime, for treatment of uncomplicated anogenital gonococcal infection in woman was on 26% (23/89) of lists. Magnesium sulfate injection for treatment of severe pre-eclampsia and eclampsia was on 50% (45/89) of the lists. CONCLUSIONS: The findings suggest that countries need to urgently amend their lists to provide all priority medicines as part of the efforts to improve maternal and child health
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