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91.
The degradation of spiramycin induced by ultraviolet (UV) irradiation was studied at pH 3–4, 6–7 and 8–9 using high-performance liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry. Furthermore, the influence of hydrogen peroxide and oxygen on the photodegradation was investigated. Three degradation products were observed in the presence of oxygen and four in the absence of oxygen. The degradation kinetics were monitored as mass area-time curves, analyzed and described using subsequent follow-up reaction first-order models. The m/z values of the degradation products were determined to be 160, 322 and 366, the latter representing two separate products, the sugar moieties of spiramycin. Remainders of the macrocycle or the intact lactone ring of spiramycin were not observed, since the conjugated π-electron system was assumed photoexcited and thus undergoing photodegradation and fast destruction of the ring. The kinetic of the degradation of spiramycin itself was described using a first-order model. The degradation was accelerated upon addition of hydrogen peroxide. In contrast, systematic acceleration depending on pH could not be found. The absence of oxygen did not lead to any significant acceleration. The findings are interpreted in terms of the effectiveness of advanced oxidation processes and their potential use as a fourth purification step in wastewater treatment plants.  相似文献   
92.

Objective

To examine the validity of police-reported alcohol data for drivers involved in fatal motor carrier crashes.

Material and Methods

We determined the availability of blood alcohol concentration (BAC) and police-reported alcohol data on 157,702 drivers involved in fatal motor carrier crashes between 1982 - 2005 using Fatality Analysis and Reporting System (FARS) data. Drivers were categorized as motor carrier drivers if they operated a vehicle with a gross vehicle weight rating of greater than 26,000 pounds. Otherwise, they were classified as non motor carrier drivers. The sensitivity and specificity of police-reported alcohol involvement were estimated for both driver types.

Results

Of the 157,702 drivers, 18% had no alcohol information, 15% had BAC results, 42% had police-reported alcohol data, and 25% had both. Alcohol information varied significantly by driver, crash, and vehicle characteristics. For example, motor carrier drivers were significantly more likely (51%) to have BAC testing results compared to non motor carrier drivers (31%) (p < 0.001). The sensitivity of police-reported alcohol involvement for a BAC level ≥ 0.08 was 83% (95% CI 79%, 86%) for motor carrier drivers and 90% (95% CI 89%, 90%) for non motor carrier drivers. The specificity rates were 96% (95% CI 95%, 96%) and 91% (95% CI 90%, 91%), respectively.

Conclusions

The sensitivity and specificity of police-reported alcohol involvement are reasonably high for drivers involved in fatal motor carrier crashes. Further research is needed to determine the extent to which the accuracy of police-reported alcohol involvement may be overestimated because of verification bias.

Impact on the Industry

Based on the results of this study, the federal government should continue to work with states to strengthen their strategies to increase chemical testing of all drivers involved in fatal crashes.  相似文献   
93.
Many causes for falls from ladders in construction are related to the user’s activities; however, the extent to which users comply with ladder use best practices is unknown and has not been well quantified before. We developed and tested an audit tool that assesses compliance with best practices guidelines for portable-ladder-use designed for applications in the construction industry. Implemented on a hand-held computer, the assessment tool consisted of a series of check-lists categorized in four groups; ladder condition, setup, moving on a ladder, and completing tasks from a ladder. For these four observational categories, the resulting tool contained 31 and 33 questions for step and extension ladders, respectively. Three individuals trained to use the tool scored a set of photographs and videos depicting 25 ladder conditions, 20 ladder setups, 10 users moving on ladders, and 13 users completing tasks from a ladder for a total of 78 observations. The assessment tool had good agreement across and within raters. For the three raters, agreement ranged from 79% to 97% across the questions. Within one subject, kappa coefficients for the intra-rater reliability ranged from 0.67 to 0.91. The tool offers a practical method to quantify best practices associated with ladder use that can ultimately inform targeted intervention efforts.  相似文献   
94.
Considerable attention is now being given to the role and importance of education and learning implications of participatory resource and environmental governance. The contention is that such learning has the potential to transform behaviour, and in the case of resource management, may help change current patterns in resource use towards a more sustainable social-ecological system. Our purpose is to establish the opportunities for learning afforded to those participating in local level resource management committees in two Cambodian fishing communities and consider the learning outcomes from such opportunities. Our approach was qualitative and used a case study design. The findings establish a wide range of committee resource management activities that resulted in both instrumental (e.g., learning about administrative procedures) and communicative (e.g., insights into the need to conserve mangroves) learning. It was revealed that such learning can lead to changes in behaviour at the community level (e.g., managing local waste). Our findings also indicated a number of motivators and enablers of learning such as opportunities for dialogue, leadership and the presence of declining resources.  相似文献   
95.
In the United States, the common interest often is conceived as a by-product of the pluralist, interest-group-driven democratic process. Special interests dominate in many political arenas. Consequently, we have lost the language, vocabulary, and ability to talk about the common interest. The way to reverse this trend is to develop and practice with new tools that allow us to articulate what we mean by the common interest in specific contexts. In this article, we leveraged the literature on procedural, substantive, and pragmatic decision making to illustrate how they work together to demonstrate whether and how the common interest was served in three case studies of Healthy Forests Restoration Act implementation on the Apache-Sitgreaves National Forest in Arizona. In two of the cases we found that the common interest was mostly served, while in the third case it was not. Our results raise questions about the ability of procedural criteria or substantive criteria alone to determine effectiveness in decision making. When evaluated together they provide a more complete understanding of how the common interest is or is not served.
Toddi A. SteelmanEmail:
  相似文献   
96.
‘Good’ governance and adaptive co-management hold broad appeal due to their positive connotations and ‘noble ethical claims’. This paper poses a fundamental question: is adaptive co-management ethical? In pursuing an answer to this question, the concept of adaptive co-management is succinctly summarized and three ethical perspectives (deontology, teleology and existentialism) are explored. The case of adaptive co-management in Cambodia is described and subsequently considered through the lens of ethical triangulation. The case illuminates important ethical considerations and directs attention towards the need for meditative thinking which increases the value of tradition, ecology, and culture. Giving ethics a central position makes clear the potential for adaptive co-management to be an agent for governance, which is good, right and authentic as well as an arena to embrace uncertainty.  相似文献   
97.
Saccopteryx bilineata has a polygynous mating system in which males defend females in a harem territory. Harem defense and courtship include energetically costly flight maneuvers and hovering displays. We tested if (1) harem males have a greater field metabolic rate than non-harem males or females and if (2) the field metabolic rate of harem males is correlated with the number of females in a harem territory. We measured the energy budget in 32 S. bilineata with the doubly labeled water method and compared these estimates with behavioral observations in the daytime roost. Among adult bats, field metabolic rate varied with body mass by an exponent of approximately two. We found no significant difference in field metabolic rate or mass-specific field metabolic rate between harem and non-harem males. The mass-specific field metabolic rate of harem-males increased with harem size. The latter finding supports the hypothesis that the energy costs of courtship display and territorial defense influence the energy budget of harem males. Overall, field metabolic rates of S. bilineata were lower than those of similarly sized bats of the temperate zone and only 2.3 times above the basal metabolic rate recorded for this species. We suggest that male S. bilineata did not take advantage of their metabolic capacity because a prudent allocation of energy to activities of harem maintenance is an adaptive strategy for males in this mating system.  相似文献   
98.
We report a case of maternal mosaic trisomy 21 ascertained at prenatal diagnosis as a result of maternal cell contamination of an amniotic fluid sample. A 34 year old female was referred for karyotyping because of a previous trisomy 21 pregnancy. Chromosome analysis of primary in situ cultures showed a karyotype of 47,XX, + 21[6]/46,XY[32]/46,XX[2]. Molecular testing demonstrated maternal cell contamination of the amniotic fluid sample and G-banded karyotyping of maternal blood showed that 3/200 cells had trisomy 21, consistent with the mother being a Down syndrome mosaic. A normal male baby with a 46,XY chromosome complement was delivered at 30 weeks. This case emphasises the need for close collaboration between cytogenetic and molecular genetics laboratories in resolving unusual cases of mosaicism. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
99.
100.
Soil-to-plant transfer factors (TF) of radiocaesium (137Cs) were determined under field condition for grassy vegetation grown in Bangladesh at contaminated land in the Atomic Energy Research Establishment (AERE) campus. TF values for rice, grass and grassy/root vegetations grown in the same type of soil were also measured under pot condition. TF values of 137Cs for grassy vegetation (2.4 x 10(-2) -4.2 x 10(-2) with an average of 3.1 x 10(-2) +/-0.005) obtained under field condition were slightly lower than the values for grass and grassy/root vegetations (2.9 x 10(-2) -6.6 x 10(-2) with an average of 4.8 x 10(-2) +/-0.01 for grass and grassy vegetations and 2.3 x 10(-2) -5.6 x 10(-2) with an average of 4.0 x 10(-2) +/-0.009 for root vegetations, respectively) obtained under pot condition. However, TF values (9.0 x 10(-3) -2.6 x 10(-2) with an average of 1.9 x 10(-2) +/-0.004) obtained for rice were about a factor of 4 lower than the values obtained for grass and grassy/root vegetations. When the properties of the AERE soils as input parameters were used in the soil-plant transfer model of Absalom, the estimated TF values (4.5 x 10(-2) -6.7 x 10(-2) with an average of 5.3 x 10(-2) +/-0.006) were consistent with the measured values obtained for grass and grassy vegetations under pot condition, however, the model overestimates the TF values for rice.  相似文献   
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