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1.

One of the most important analysis in many hydrological and agricultural studies is to convert the daily rainfall data into sub-daily (hourly) because in many rainfall stations, only the daily rainfall data are available and for a comprehensive rainfall analysis, these data should be converted to sub-daily. Many experimental and analytical methods are available for this conversion but one of the simplest yet accurate ones has been proposed by the Indian Meteorological Department (IMD). Since the IMD method has shown low accuracy in some regions, in this study, the IMD method is modified to a single parameter equation, called Modified Indian Meteorological Department (MIMD) in order to improve the accuracy of the conversion. For this reason, the parameter is calibrated so that the maximum correlation between observed and estimated values is achieved. Five stations in different regions with different climatic conditions were selected so that the daily and sub-daily rainfall data were available in each of them. Then, the parameter of the MIMD method was derived for each station. The results were compared with both observed data and IMD method and it was shown that the mean correlation coefficient of MIMD and IMD methods were 0.9 and 0.73 respectively for 12-h rainfall depth which indicated that the accuracy of the MIMD method in estimation of sub-daily rainfall depths was significantly increased. Moreover, the results showed that the accuracy of the MIMD method decreases as rainfall duration decreases.

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2.
This paper presents a middleware platform for managing devices that operate in heterogeneous environments. The proposed management framework supports terminal-controlled, preference-based access network selection. Two separate problems are identified in this domain: one involving the computation of optimal allocations of services to access networks and quality levels (service configuration), and one concerning the dynamic inference of the user’s preferences, according to the usage context (user profiling). This paper includes an approach to the definition, mathematical formulation and solution of both these problems. Indicative results of the proposed solution methods are presented in the context of a real-life scenario simulating a day in the life of an ordinary user.  相似文献   
3.
In this paper we develop and test a model of the associations between major project managers' personal attributes and project success in the context of the Australian Defence industry. In our model, emotional intelligence, cognitive flexibility and systemic thinking were hypothesised to relate to project success, mediated by internal and external stakeholder relationships. The model was tested in an online survey with 373 major project managers. Emotional intelligence and cognitive flexibility were found to be related to the development, quality and effectiveness of major project managers' relationships with both internal and external stakeholders; and these in turn were associated with their ratings of project success. Systemic thinking, however, had no relationship with either stakeholder relationships or project success. Additional research is needed to examine the contribution of a wider range of personal attributes to stakeholder relationships and project success, and to assess whether this model is applicable in other industries and types of projects.  相似文献   
4.
Turkey, situated at the junction of two continents, benefits both from its rich Asian legacy and its proximity to neighboring European countries. Although the level of socioeconomic development places the country clearly in the group of developing countries, Turkey has been a candidate country for admission to the European Union (EU) since 1999. As a result, the conditions for capacity building in agricultural biotechnology include elements from both the industrialized and developing countries. Because of its favorable climate and time-tested farming traditions dating back to ancient Mesopotamia, the country possesses one of the richest floras in the world. This review attempts to illuminate the role and importance of local actors in introducing modern biotechnology to the Turkish agricultural system. Agricultural biotechnology, specifically plant biotechnology, has a high priority in the Turkish government's program. Public-funded research and education in this field is given due priority, but research by the private sector is relatively poorly funded. The ongoing field trials with genetically modified seeds are conducted mostly by multinational companies whose aim it is to commercialize the genetically modified organisms (GMOs) as soon as legislation concerning biotechnology is implemented. The attitude of the big farm owners to genetically modified crops is positive because they expect economic advantages from these crops. On the other hand, public awareness about genetically modified food is quite low, and neither the consumer organizations nor the media represent a particular power in this area. Thus, the power centers in agricultural biotechnology are the government and the multinational biotech companies. The local industry, the consumers, and the media have relatively less input. Moreover, communication between groups is fairly poor, and this contributes to a growing gap between the strong and the weak actors. Turkey has already decided to implement the EU regulation in contained use and the deliberate release of GMOs, which has been shaped in the European sociopolitical environment where the consumers and their organizations represent a powerful force, and where the power constellation between the actors is quite different. Nevertheless, it can be argued, that this route might still be the right choice for Turkey during the phase of introducing this high-tech method of production to its agriculture.  相似文献   
5.
Structured lipids resembling human milk fat and containing GLA were synthesized by an enzymatic interesterification between tripalmitin, hazelnut oil FA, and GLA in n-hexane. Commercially immobilized 1,3-specific lipases, lipozyme® RM IM and Lipozyme® TL IM, were used as the biocatalysts. The effect of these enzymes on the incorporation levels was investigated. A central composite design with five levels and three factors—substrate ratio, reaction temperature, and time—were used to model and optimize the reaction conditions via response surface methodology. Good quadratic models were obtained for the incorporation of GLA (response 1) and oleic acid (response 2) by multiple regression and backward elimination. The determination coefficient (R 2) values for the models were found to be 0.92 and 0.94 for the reactions catalyzed by Lipozyme RM IM, and 0.92 and 0.88 for the reactions catalyzed by Lipozyme TL IM, respecitively. The optimal conditions generated from the models for the targeted GLA (10%) and oleic acid (45%) incorporation were 14.8 mol/mol, 55°C, and 24 h; 14 mol/mol, 55°C, and 24 h for substrate ratio (moles total FA/mol tripalmitin), temperature and time for the reactions catalyzed by Lipozyme RM IM and Lipozyme TL IM, respectively. Human milk fat substitutes containing GLA that can be included in infant formulas were success-fully produced using both Lipozyme RM IM and Lipozyme TL IM enzymes. The effect of the two enzymes on the incorporation of GLA and oleic acid were found to be similar.  相似文献   
6.
In 2003, a subsurface flow constructed wetlands (SSF-CW) system was built at the University of Vermont (UVM) Paul Miller Dairy Farm as an alternative nutrient management approach for treating barnyard runoff and milk parlour waste. Given the increasing problem of phosphorus (P) pollution in the Lake Champlain region, a slag based P-removal filter technology (PFT) was established (2004) at the CW with two objectives: (i) to test the filters' efficiency as an upgrade unit for improving P removal performance via SSF-CW (ii) to investigate the capacity of filters technology to remove P as a "stand alone" unit. Six individual filters (F1-F6) were filled with electric arc furnace (EAF) steel slag, each containing 112.5 kg of material with a pore volume of 21 L. F1-F4, fed with CW treated water, received approximately 2.17 g DRP kg(-1) EAF steel slag (0.25 kg DRP total) during the 259 day feeding period. F1-F4 retained 1.7 g DRP kg(-1) EAF steel slag, resulting in an average P removal efficiency of 75%. The addition of filters improved CW DRP removal efficiency by 74%. F5 and F6, fed non-treated water, received 1.9 g DRP kg(-1) EAF steel slag (0.22 kg DRP in total) and retained 1.5 g DRP kg(-1) resulting in a P removal efficiency of 72%. The establishment of the EAF slag based PFT is the first in-field evaluation of this technology to reduce P from dairy farm effluent in Vermont.  相似文献   
7.
The aim of the present study was to develop a rapid and simple method for the detection and quantification of antibiotic and antibacterial residues in honey using liquid chromatography with electronspray ionization tandem mass spectrometry. Two different extraction methods were used. The first method uses water and 1% formic acid in acetonitrile for the determination of sulfonamides while the second uses phosphate buffer, 10% trichloroacetic acid, and acetonitrile as the extracting solvent for the determination of tetracyclines, amphenicols, fluoroquinolones, penicillin g, trimethoprim, and tiamulin. The multi-residue method was validated in a thyme honey matrix. Thirty-six different antibiotics and residues from four different families (sulfonamides, tetracyclines, amphenicols, fluoroquinolones) and some individual antibiotics (penicillin g, trimethoprim, and tiamulin) were tested in 20 honey samples originating from Cyprus and Greece. The decision limits (CCα) were from 0.1 to 9.2 μg kg?1; the detection capabilities (CCβ) were from 0.3 to 27.6 μg kg?1 while recoveries were from to be between 65.0 and 116.1%. The method was successfully applied to commercial samples from different types of honey from Greece and Cyprus. Among them, oxolonic acid, sulfathiazole, and sulfadimethoxine were found in three honey samples. Finally, proficiency testing was applied to the proposed method while analysis of certified samples showed good method performance characteristics.  相似文献   
8.
Health risks of genetically modified foods   总被引:3,自引:0,他引:3  
As genetically modified (GM) foods are starting to intrude in our diet concerns have been expressed regarding GM food safety. These concerns as well as the limitations of the procedures followed in the evaluation of their safety are presented. Animal toxicity studies with certain GM foods have shown that they may toxically affect several organs and systems. The review of these studies should not be conducted separately for each GM food, but according to the effects exerted on certain organs it may help us create a better picture of the possible health effects on human beings. The results of most studies with GM foods indicate that they may cause some common toxic effects such as hepatic, pancreatic, renal, or reproductive effects and may alter the hematological, biochemical, and immunologic parameters. However, many years of research with animals and clinical trials are required for this assessment. The use of recombinant GH or its expression in animals should be re-examined since it has been shown that it increases IGF-1 which may promote cancer.  相似文献   
9.
BACKGROUND AND PURPOSE: Power Doppler imaging (PDI) is a new sonographic technique that has recently been introduced for vascular application. Since the technical principles of PDI may provide increased sensitivity to visualize the continuity of blood flow in arterial stenoses, we investigated the diagnostic significance of PDI and the intermethod relationship for the measurement and classification of internal carotid artery (ICA) stenosis in comparison with both color Doppler flow imaging (CDFI) and angiography. METHODS: One hundred patients with a total of 128 ICA stenoses (50% to 69%, n = 37; 70% to 79%, n = 27; 80% to 99%, n = 64) and 12 ICA occlusions were consecutively investigated by means of PDI, CDFI, and intra-arterial angiography (n = 48). Reduction of the intrastenotic lumen was measured on longitudinal and transverse views of PDI and CDFI for the calculation of the degree of diameter and area stenosis, respectively. Angiographic stenosis was determined with the use of the North American Symptomatic Carotid Endarterectomy Trial (NASCET), European Carotid Surgery Trial (ECST), and common carotid (CC) methods. RESULTS: PDI provided significantly more excellent or good (92% versus 79%; P < .01) displays of the intrastenotic lumen than CDFI, particularly in complicated high-grade stenosis. While linear regression analysis demonstrated a high overall correlation between PDI and CDFI for diameter (r = .88; P < .001) and area stenosis (r = .79; P < .001), categorization of ICA stenosis revealed best agreement for 80% to 99% area stenoses. Since angiography frequently either underclassified (NASCET method) or overclassified (ECST, CC methods) the degree of ICA stenosis in comparison to both PDI and CDFI, the sonographic-angiographic correlation was only moderate (regression coefficients ranged from .62 to .70; P < .001). CONCLUSIONS: PDI further improves the assessment of ICA stenosis by providing better visualization of the stenotic vascular lumen than CDFI. Sonographic imaging of the stenotic plaque on both PDI and CDFI provided a direct measurement of the local degree of stenosis, while the angiographic grade of stenosis essentially depended on the method used for evaluation.  相似文献   
10.
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