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31.
Field isolates of Didymella applanata, the causal agent of spur blight of raspberry, were evaluated in vitro for their sensitivity to mancozeb, chlorothalonil, captan, fluopyram, boscalid and difenoconazole. A total of 10 isolates, collected during 2013 at five localities in the major raspberry growing region in Serbia, and characterized as copper hydroxide, dithianon, and tebuconazole (sensitive), pyraclostrobin (sensitive or highly resistant) and fluazinam (sensitive or moderately resistant), were used in this study. The EC50 values for the isolates ranged from 1.33 to 2.88 mg L?1 for mancozeb, from 3.18 to 6.65 mg L?1 for chlorothalonil, from 15.75 to 24.69 mg L?1 for captan and from 1.80 to 8.20 mg L?1 for fluopyram. The narrowest range of EC50 values was recorded for difenoconazole (0.23–0.49 mg L?1), whereas the widest range was obtained for boscalid (4.49–49.25 mg L?1). The calculated resistance factors showed that all D. applanata isolates were sensitive to mancozeb, chlorothalonil, captan, and difenoconazole. Four isolates were moderately resistant to boscalid, while three of them were also moderately resistant to fluopyram. This finding of moderately resistant isolates to these SDHI fungicides indicates a possible cross-resistance which should be clarified in further investigations.  相似文献   
32.
The influence of buffer strips and soil texture on runoff of flufenacet and isoxaflutole was studied for two years in Northern Italy. The efficacy of buffer strips was evaluated on six plots characterized by different soil textures; two plots had Riva soil (18.6% sand, 63.1% silt, 18.3% clay) while the remaining four plots had Tetto Frati (TF) soil (37.1% sand, 57% silt, 5.9% clay). Additionally, the width of the buffer strips, constituted of spontaneous vegetation grown after crop sowing, was also compared for their ability to abate runoff waters. Chemical residues in water following runoff events were investigated, as well as their dissipation in the soil. After the first runoff events, concentrations of herbicides in water samples collected from Riva plots were as much as four times lower in waters from TF plots. On average of two growing seasons, the field half-life of flufenacet in the upper soil layer (5 cm) ranged between 8.1 and 12.8 days in Riva soil, 8.5 and 9.3 days in TF soil. Isoxaflutole field half-life was less than 1 day. The buffer strip was very affective by the uniformity of the vegetative cover, particularly, at the beginning of the season. In TF plots, concentration differences were generally due to the presence or absence of the buffer strip, regardless of its width.  相似文献   
33.
The intent of this research is to investigate how the customers of a technological control laboratory for civil construction materials perceived the quality of the services delivered by the lab, specifically in regard to the service of concrete compression testing. The popular SERVQUAL scale, a multidimensional instrument used to capture customer expectations and perceptions, was used as a model for the application of a survey. Exploratory factor analyses were employed to evaluate customers’ perceptions and experiences of service quality in regard to the dimensions and accompanying attributes of the SERVQUAL scale. Twenty attributes, which were grouped within five dimensions (Reliability, Assurance, Tangibles, Responsiveness, and Empathy), were identified, explaining 80.417% of the variance between customer expectations and perceptions and characterizing these dimensions on a modified SERVQUAL scale. Analysis of the results allowed us to identify discrepancies in perceived service quality compared with customers’ expectations. Most of the identified gaps between expectations and perceptions resulted in negative values.  相似文献   
34.
The general objective of this in vitro study was to examine the effect of bee pollen on the release of insulin-like growth factor I (IGF-I) and steroid hormone progesterone, and expression of markers of proliferation (PCNA) and apoptosis (caspase-3) in porcine ovarian granulosa cells. Concentrations of IGF-I and progesterone were determined by RIA method and expression of PCNA and caspase-3 by immunocytochemistry. Bee pollen addition at the dose of 10 ng/mL significantly (P<0.05) inhibited IGF-I release by porcine ovarian granulosa cells. This growth factor was not influenced by 100 and 1000 ng/mL doses of bee pollen. Progesterone release by cells was not influenced by bee pollen addition at the doses of 10, 100 and 1000 ng/mL as used in our study. Similarly expression of PCNA and caspase-3 was not affected by bee pollen addition. The present study shows dose-dependent regulation of IGF-I by experimental bee pollen addition in vitro. Progesterone release, expression of PCNA and caspase-3 in porcine ovarian granulosa cells was not induced by pollen. Our results contribute to new insights regarding the possible effect of bee pollen on IGF-I release, which is important for regulation of porcine ovarian functions.  相似文献   
35.
The results of measurements of Krypton-85 (85Kr) concentrations in the ground-level air of Prague between 1983 and 1992 are presented and time-related changes analysed. The long-term trend in activity level of 85Kr has been steadily increasing with a growth rate of 0.04 Bq.m–3 (STP) per year. Some peaks of 85Kr activity were observed due to the influence of undispersed radioactive plumes coming from distant sources. Short-term variations within a typical range of concentrations from 0.61 to 1.25 Bq.m–3 (STP) were found to be seasonally dependent, with the maximum occurring in spring.  相似文献   
36.
ABSTRACT

A laboratory procedure was developed and verified for stabilizing salt produced by an industrial waste incinerator. This procedure is based on salt stabilization by means of an asphalt binder. Conductivity values and relevant anion contents in leachates of stabilized waste with an asphalt coating were near zero. The pH value of these leachates equaled the pH value of the water used, so that the stabilized waste salt represented inert material, posing no environmental hazard. An unusually significant reduction in the volume of processed salt occurred during stabilization. After compacting under 10.4 MPa pressure, the volume of test specimens was almost 55% smaller than the initial salt volume. In practice, this would mean more than a doubling of landfill waste capacity. Volume reduction was successfully explained by means of a mathematical model.  相似文献   
37.
A rapid Biacore biosensor immunoassay of 4-nonylphenols was developed. Two types of antibodies were used in the study: polyclonal antibodies with high cross-reactivity towards technical 4-nonylphenol and a monoclonal antibody very specific to 4-n-nonylphenol. 9-(p-Hydroxyphenyl)nonanoic acid was immobilized onto surface of a sensor chip. The best assay sensitivity was achieved using a flow rate of 50 microl min(-1) and injection time of 2 min. For the assay incorporating monoclonal antibodies a limit of detection 2 ng ml(-1) for 4-n-nonylphenol was achieved. With polyclonal antibodies one order lower sensitivity was observed for 4-nonylphenols. High background level of calibration curve for technical 4-nonylphenol was decreased by using IgG fraction of polyclonal antibodies in combination with lower amount of immobilised 9-(p-hydroxyphenyl)nonanoic acid. Sensitivity of the assay was improved by using a chip with a new derivative on a surface-N-aminobutyl [2-(4-hydroxyphenyl)ethylamine] (limit of detection--5 ng ml(-1)). Applicability of the developed assays to ecological monitoring was checked in experiments using shellfish samples. 4-n-Nonylphenol from spiked samples was extracted into hexane followed by clean-up on NH2 SPE columns. Calibration curves generated for cockles, mussels and oyster samples were identical (limit of detection about 10 ng g(-1)) whereas for scallop samples a slight decrease (about 5-10%) of absolute response was observed. In the assay using the monoclonal antibody specific to 4-n-nonylphenol 31 shellfish samples were found to be negative. Results obtained with polyclonal antibodies indicated that two scallop samples contained a quantity of 4-nonylphenols. The developed biosensor assay could be applied for shellfish analysis as a preliminary screening method.  相似文献   
38.
This paper provides a resource-based assessment of the available agricultural crop residues for bioenergy production in the European Union, at the level of the 27 Member States. The assessment provides the amount of the residues produced, collected, their present uses and the residues left available for bioenergy. This study considers the crop production and yields and multi-annual yield variation for each crop. The calculation was based on specific residues to product ratios, which were determined, depending on the crop type and crop yield. Sustainable removal rates were considered in order to protect soil fertility. The results show large spatial and temporal variations of available crop residues within EU27. The average amount of crop residues available for bioenergy in EU27 was estimated at 1530 PJ/year, with a variation between 1090 and 1900 PJ/year. The average value represents about 3.2% in final energy consumption in the EU27 while the variation 2.3–4%. This variation, which is even larger at the level of Member States, may result in shortages in biomass supply in some years, when crop residues are available in a lower amount than the average.  相似文献   
39.
40.
Objective: Powered 2-wheeled motor vehicles (PTWs) are one of the most vulnerable categories of road users. Bearing that fact in mind, we have researched the effects of individual and environmental factors on the severity and type of injuries of PTW users. The aim was to recognize the circumstances that cause these accidents and take some preventive actions that would improve the level of road safety for PTWs.

Methods: In the period from 2001 to 2010, an analysis of 139 road accidents involving PTWs was made by the Faculty of Transport and Traffic Engineering in Belgrade. The effects of both individual (age, gender, etc.) and environmental factors (place of an accident, time of day, etc.) on the cause of accidents and severity and type of injuries of PTWs are reported in this article. Analyses of these effects were conducted using logistic regression, chi-square tests, and Pearson's correlation.

Results: Factors such as categories of road users, pavement conditions, place of accident, age, and time of day have a statistically significant effect on PTW injuries, whereas other factors (gender, road type; that is, straight or curvy) do not. The article also defines the interdependence of the occurrence of particular injuries at certain speeds. The results show that if PTW users died of a head injury, these were usually concurrent with chest injuries, injuries to internal organs, and limb injuries.

Conclusions: It has been shown that there is a high degree of influence of individual factors on the occurrence of accidents involving 2-wheelers (PTWs/bicycles) but with no statistically significant relation. Establishing the existence of such conditionalities enables identifying and defining factors that have an impact on the occurrence of traffic accidents involving bicyclists or PTWs. Such a link between individual factors and the occurrence of accidents makes it possible for system managers to take appropriate actions aimed at certain categories of 2-wheelers in order to reduce casualties in a particular area. The analysis showed that most of the road factors do not have a statistically significant effect on either category of 2-wheeler. Namely, the logistic regression analysis showed that there is a statistically significant effect of the place of accident on the occurrence of accidents involving bicyclists.  相似文献   

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