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21.
Environment, Development and Sustainability - Multi-attribute decision-making (MADM) is an umbrella term to describe a series of mathematical frameworks that, in essence, enable the decision-makers...  相似文献   
22.
Journal of Polymers and the Environment - Cellulose was initially extracted from Safflower (Carthamus tinctorius L.) stem wastes and used for the preparation of a fully bio-based adsorbent polymer...  相似文献   
23.

Oral mucositis (OM) is one of the cancer chemotherapy-related side effects which can affect the quality of life of affected patients. This study was designed to investigate the healing effect of Elaeagnus angustifolia in 5-flurouracil (5-FU)-induced OM in golden hamster. Fifty-six adult male golden hamsters received three intraperitoneal injections of 5-FU at a dose of 60 mg/kg on days 0, 5, and 10. The cheek pouch mucosa was scratched superficially under local anesthesia. Then, two horizontal scratches were made across the everted cheek pouch on days 3 and 4. All treatments were started on day 12 for equal number of animals in control group with no treatments, gel base group that was treated with carboxy methyl cellulose as gel base which used in preparation of the topical gel, topical gel group that used gel containing 10% hydroalcoholic extract of E. angustifolia (HEEA) topically, and dietary group which was treated with 300 mg/kg HEEA. At 2 and 5 days after treatment, blood and pouch tissue sampling were done and analyzed for blood composition, tissue malondialdehyde (MDA) level, and myeloperoxidase (MPO) and superoxide dismutase (SOD) activities plus histopathological evaluations. Both topically and orally HEEA-treated groups showed a significant relief in OM compared to the control and base gel groups. However, the systemic form had higher efficiency in some parts especially decreasing the MPO (0.27 ± 0.17 vs. 0.56 ± 0.17 IU/L) and increasing SOD (6.46 ± 0.15 vs. 5.36 ± 0.18 IU/L) activities in pouch tissue in comparison to topical form mostly at 5 days after treatment. It seems that hydroalcoholic extract of E. angustifolia can be used as an appropriate drug choice for the treatment of oral mucositis based on its healing stimulatory and anti-inflammatory properties.

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24.
Objectives. Musculoskeletal disorders (MSDs) are prevalent among airline baggage handlers due to manual materials handling. In this study, the Nordic musculoskeletal questionnaire (NMQ), the revised National Institute for Occupational Safety and Health (NIOSH) lifting equation, and the University of Michigan 3D Static Strength Prediction Program? (3DSSPP) were used to analyze MSDs among baggage handlers. Methods. The NMQ was filled out by 209 baggage handlers and 46 arbitrarily selected baggage handlers were evaluated using the NIOSH method and 3DSSPP. Results. The obtained results showed that the most common MSDs occurred in the lower back region. The next risky regions included knees, neck, and upper back, respectively. The NIOSH results confirmed that the subjects lifted loads heavier than the permitted limit and their lifting postures were inappropriate. The results of the 3DSSPP also indicated that compression forces exceeded the NIOSH limit in these awkward postures. Conclusions. Relying on this study, holding compulsory ergonomic lifting training courses could be proposed for workers and regulations adjusting an upper limit for maximum baggage weight must be also enacted in order to improve occupational health and prevent the prevalence of increasing MSDs.  相似文献   
25.
Reverse stream flood routing determines the upstream hydrograph in a stream reach given the downstream hydrograph. The Muskingum model of flood routing involves parameters that govern the routed hydrograph. These parameters are herein estimated using simulation methods coupled with optimization tools to achieve optimized parameters. Different simulation methods are shown to perform unequally in the estimation of nonlinear Muskingum parameters. This paper presents two simulation methods for nonlinear Muskingum reverse flood routing: (1) Euler equations and (2) Runge-Kutta 4th order equations. Moreover, the generalized reduced gradient (GRG) is used as the optimization tool that minimized the sum of the squared deviations (SSQ) between observed and routed inflows in a benchmark flood routing problem. Results show the Runge-Kutta 4th order equations yield better routed hydrographs with smaller SSQ than obtained in previous research and with the first simulation method (Euler equations).  相似文献   
26.
The basic aim of this work is (1) to review and present practically operational requirements for a sustainability assessment of marine environment, such as describing the monitoring process, research approaches, objectives, guidelines, and indicators and (2) to illustrate how physico-chemical and biological indicators can be practically applied, to assess water and sediment quality in marine and coastal environment. These indicators should meet defined criteria for practical usefulness, e.g. they should be simple to understand and apply to managers and scientists with different educational backgrounds. This review aimed to encapsulate that variability, recognizing that meaningful guidance should be flexible enough to accommodate the widely differing characteristics of marine ecosystems.  相似文献   
27.
Ferula xylorhachis Rech.f. is an endemic plant species belonging to the Apiaceae family and distributed in northeastern Iran. In the present study, we attempted to determine the factors with the greatest effects on the distribution of this species and to determine suitable regions for it based on current and future conditions. The Maximum Entropy method was used in the present study and the results indicated that the Mean Temperature of Wettest Quarter (48.2%), Precipitation of Wettest Quarter (49.1%), and Precipitation of Wettest Month (61.4%) are the most important factors in the current and in two future periods (2040 and 2070). The models suggest that suitable regions for the presence of this species will change over time and that the species will encounter limitations through changes such as moisture reduction. According to the A1B scenario, increases in greenhouse gases such as CO2 and CH4 will have direct effects on future precipitation and temperature and these factors will be important in determining species dispersion. Evaluation of important habitat factors using normal ecological methods will help in developing the best conservation programs in the future. Introducing species to new regions will help to protect them from the extinction risk caused by climate change.  相似文献   
28.
This study investigated the combined effect of firefighting operations and exposure to smoke on physiological responses, cognitive functions and physical performance among firefighters. Each firefighter was engaged in two experimental conditions: (a) without artificial smoke, control (NS); (b) with artificial smoke (WS). The results of data analysis revealed that heart rate and body temperature increased significantly after the firefighting activities in the two conditions relative to baseline. In addition, reaction time (RT) and correct response (CR) decreased after the activity relative to baseline and there was a significant difference in RT and CR between the NS and WS conditions. There was also a significant difference in performance time between the NS and WS conditions. These findings demonstrated that a smoke compound has an insignificant effect on physiological responses during firefighting activity. On the contrary, the smoke compound has a detrimental influence on cognitive and physical performance.  相似文献   
29.
Abstract: A numerical model has been developed to simulate the hydraulic and heat transfer properties of a stormwater detention pond, as part of a simulation tool to evaluate thermal pollution of coldwater streams from stormwater runoff. The model is dynamic (unsteady) and based on principles of fluid mechanics and heat transfer. It is driven by hourly weather data, and specified inflow rates and temperatures. To calibrate and validate the pond model field data were collected on a commercial site in Woodbury, Minnesota. The relationship between pond inflow and outflow rates to precipitation was effectively calibrated using continuously recorded pond levels. Algorithms developed for surface heat transfer in lakes were found to be applicable to the pond with some modification, resulting in agreement of simulated and observed pond surface temperature within 1.0°C root mean square error. The use of an unshaded pond for thermal mitigation of runoff from paved surfaces was evaluated using the pond model combined with simulated runoff from an asphalt parking lot for six years of observed rainfall events. On average, pond outflow temperature was 1.2°C higher than inflow temperature, but with significant event‐to‐event variation. On average, the pond added heat energy to runoff from an asphalt parking lot. Although the pond added total heat energy to runoff, it did reduce the rate of heat outflow from the pond by an order of magnitude due to reductions in volumetric outflow rate compared with the inflow rate. By reducing the rate of heat flow, the magnitude of temperature impacts in a receiving stream were also reduced, but the duration of impacts was increased.  相似文献   
30.
The purpose of this article is Artificial Neural Network (ANN) modeling using ecological and associated factors with forest degradation to predict the degradation of ecosystem, thereby enabling us to assess the environmental impacts of forest projects as an Environmental Decision Support System (EDSS). Results of the Multi-Layer Feed-Forward Network (MLFN), trained for Optimized Forest Degradation Model (OFDM), indicate that the performance of OFDM is more than other degradation models. Changes in forest management activities with higher value in sensitivity analysis help forest managers to decrease OFDM entity and environment impacts. The system is an intelligent EDSS, which allows the decision-maker to model criteria in forest degradation in order to reach and employ the optimal allocation plan. Considering results, multi criteria decision analysis (MCDA) approaches based on ANN, is an encouraging and robust method for solving MCDA problems.  相似文献   
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