1,539 research outputs found
Delayed surgical debridement in pediatric open fractures: a systematic review and meta-analysis.
Purpose: Open fractures are considered orthopedic emergencies that are traditionally treated with surgical debridement within 6 h of injury to prevent infection. However, this proclaimed “6-h rule” is arbitrary and not based on rigorous scientific evidence. The aim of our study was to systematically review the literature that compares late (>6 h from the time of injury) to early (<6 h from the time of injury) surgical debridement of pediatric open fractures.
Methods: We searched several databases from 1946 to 2013 for any observational or experimental studies that evaluated late and early surgical debridement of pediatric open fractures. We performed a meta-analysis using a random effects model to pool odds ratios for a comparison of infection rates between children undergoing late versus early surgical debridement. We also investigated the infection rates in upper- and lower-limb pediatric open fractures. Descriptive, quantitative, and qualitative data were extracted.
Results: Of the 12 articles identified, three studies (retrospective cohort studies) were eligible for the meta-analysis, encompassing a total of 714 open fractures. The pooled odds ratio (OR = 0.79) for infection between late and early surgical debridement was in favor of late surgical debridement but was not statistically significant (95 % CI 0.32, 1.99; p = 0.38, I 2 = 0 %). No significant difference in infection rate was detected between pediatric open fractures in the upper and lower limbs according to the time threshold in the included studies (OR = 0.72, 95 % CI 0.29, 1.82; p = 0.40, I 2 = 0 %).
Conclusions: The cumulative evidence does not, at present, indicate an association between late surgical debridement and higher infection rates in pediatric open fractures. However, initial expedient surgical debridement of open fractures in children should always remain the rule. Thus, multi-center randomized controlled trials or prospective cohort studies will be able to answer this question with more certainty and a higher level of evidence
Systematic review of brucellosis in the Middle East: disease frequency in ruminants and humans and risk factors for human infection
This paper considers the problem of finding global states incoming to a specified global state in a Boolean network, which may be useful for pre-processing of finding a sequence of control actions for a Boolean network and for identifying the basin of attraction for a given attractor, We show that this problem is NP-hard in general along with related theoretical results, On the other hand, we present algorithms that are much faster than the naive exhaustive search-based algorithm. ©2007 IEEE.link_to_subscribed_fulltex
Optimal management of irrigation and vadose zone pesticide transport
A management model is developed for maximizing crop yield while avoiding unacceptable pesticide leaching. Utilized constraint equations: maintain a soil moisture volume balance, describe downward pesticide transport, and limit the amount of pesticide reaching groundwater. The reported optimization model is the first which includes unsaturated zone pesticide transport. It is designed to help prevent nonpoint-source contamination of shallow groundwater aquifers. The model computes optimal irrigation amounts for given soil, crop, chemical, and climate data and irrigation frequencies. The model is tested for different irrigation scenarios. The modeling approach is promising as a tool to aid developing environmentally sound agricultural production practices. It allows estimation of trade-offs between crop production and groundwater protection for different management strategies. More frequent irrigation tends to give better crop production and less solute movement. Yield/environmental quality trade-offs are smaller for deeper groundwater tables. Trade-offs also decrease with increased irrigation frequency
How Viable Is the UTAUT Model in a Non-Western Context?
The present research examines the plausibility of Unified Theory Acceptance and Use Technology (UTAUT) model in predicting internet banking behaviour as a newly adopted technology third world countries. Data is collected from three Arab countries: Jordan, Saudi Arabia and Egypt. Confirmatory factor analysis is applied to test constructs measurement and model hypotheses. Findings are congruent with model testing under conditions of volitional usage behaviour. In this regard, the role of facilitating conditions variable is insignificant as a determinant of usage behaviour. Social norms variable also proved to be weak determinant of behavioural intentions mainly owing to users’ experience. Findings demonstrate effort expectancy as the key determinant of internet banking usage behaviour in the examined markets, while users’ experience moderates the impact of effort expectancy on behavioural intention. Results should enhance our understanding of internet banking usage in developing countries and support e-services promoting in this region
Nonthermal Laser-Induced Formation of Crystalline Ge Quantum Dots on Si(100)
The effects of laser-induced electronic excitations on the self-assembly of Ge quantum dots on Si (100) - (2×1) grown by pulsed laser deposition are studied. Electronic excitations due to laser irradiation of the Si substrate and the Ge film during growth are shown to decrease the roughness of films grown at a substrate temperature of ∼120 °C. At this temperature, the grown films are nonepitaxial. Electronic excitation results in the formation of an epitaxial wetting layer and crystalline Ge quantum dots at ∼260 °C, a temperature at which no crystalline quantum dots form without excitation under the same deposition conditions.© 2008 American Institute of Physics. [DOI: 10.1063/1.3041493
Standards Affecting Increasing the Resistance of Laboratory Clothing Fabrics to Chemicals
This study focuses on identifying the criteria that affect the harm and danger laboratory workers and students face from chemical reactions and combustion resulting from mixing chemicals. The study investigates the impact of fabric type, weave structure, and weft density on the resistance of laboratory clothing fabrics to chemicals. Laboratory tests were conducted to produce textile products that meet resistance specifications. The study found that the processing method used had a significant effect on improving the properties of ignition resistance and resistance to fluid permeability within the fabrics. The study used an experimental descriptive approach and statistical analysis with the SPSS program to process the data
AUDIT REPORT LAG: DO COMPANY CHARACTERISTICS AND CORPORATE GOVERNANCE FACTORS MATTER? EMPIRICAL EVIDENCE FROM LEBANESE COMMERCIAL BANKS
The objective of this study is to investigate the determinants (company specific characteristics and corporate governance factors) of audit report lag (ARL) in a developing country, namely, Lebanon. This paper adds and contributes to the limited literature that investigated the determinants of ARL in the developing Middle East countries through focusing on the Lebanese context. The study is carried out depending on a sample of Lebanese commercial banks operating in Lebanon, covering the period from 2012 to 2017. The researchers used the multiple regression analysis to examine the impact of the explanatory variables on ARL. The results show a significant relationship between ARL and each of bank size, leverage, board independence, board diligence, audit committee (AC) independence, and AC diligence. The regression outcomes reveal that banks with longer ARL are smaller, have higher leverage, their boards and ACs are less diligence, their boards are more independent, and their ACs include less independent and non-executive members
Preventing pesticide contamination of groundwater while maximizing irrigated crop yield
A simulation/optimization model is developed for maximizing irrigated crop yield while avoiding unacceptable pesticide leaching. The optimization model is designed to help managers prevent non-point source contamination of shallow groundwater aquifers. It computes optimal irrigation amounts for given soil, crop, chemical, and weather data and irrigation frequencies. It directly computes the minimum irrigated crop yield reduction needed to prevent groundwater contamination. Constraint equations used in the model maintain a layered soil moisture volume balance; describe percolation, downward unsaturated zone solute transport and pesticide degradation; and limit the amount of pesticide reaching groundwater. Constraints are linear, piecewise linear, nonlinear, and exponential. The problem is solved using nonlinear programming optimization. The model is tested for different scenarios of irrigating corn. The modeling approach is promising as a tool to aid in the development of environmentally sound agricultural production practices. It allows direct estimation of trade-offs between crop production and groundwater protection for different management approaches. More frequent irrigation tends to give better crop yield and reduce solute movement. Trade-offs decrease with increasing irrigation frequency. More frequent irrigation reduces yield loss due to moisture stress and requires less water to fill the root zone to field capacity. This prevents the solute from moving to deeper soil layers. Yield-environmental quality trade-offs are smaller for deeper groundwater tables because deeper groundwater allows more time for chemical degradation
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