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21.
The purpose of the study was to examine the antiradical activity of 11 natural honeys and to evaluate the antifungal properties of honey. Honey samples (10) were collected from different locations of Slovak Republic. Honeys were native to different plant species of Robinia pseudoacaccia, Brassica napus subs. napus, Castanea sativa Mill. Thymus serpyllum vulgaris and the other samples had multifloral origin. The low antiradical activitity in honey samples was determined. The best results were found in thyme honey from Rhodos (11.84 %) and Castanea honey from Nitra (10.61 %). The lowest antiradical activity was found in Acacia honey and determined to be 7.62 %. Statistically significant differences (P< 0.001) were found among thyme/Rhodos and Castanea/Nitra. The antifungal activities of honey samples were tested by 10 %, 25 % and 50 % (by mass per volume) concentration against fungi Penicillium crustosum, P. expansum, P. griseofulvum, P. raistrickii and P. verrucosum and by the agar well diffusion method. The solutions containing 10 % (by mass per volume) of honey did not have any effect on the growth of fungi. The strongest antifungal effect was shown by 50 % honey concentration against P. raistrickii.  相似文献   
22.
The types of treatment most commonly used by pulp mills are biological treatments in combination with sedimentation or coagulation/flocculation as pretreatment. The main issues faced by these types of treatment are low efficiency in the removal of organic matter and the loss of aggregate value for the recovered fiber. Therefore, this study aims to evaluate the use of microfiltration (MF) combined with a membrane bioreactor (MBR) for the treatment of bleach pulp mill effluents. The results showed that the use of the MF-MBR system was an excellent alternative for the treatment of bleach pulp mill effluents with an average COD removal of 95%. The microfiltration allowed the recovery of fibers, which can be returned to the production process without losing economic value, and produced a better quality effluent for further treatment in the MBR. The MBR presented high efficiency removal of organic matter.  相似文献   
23.
While the concept of sustainable development brings together concepts of economic, environmental and social sustainability, much has been said regarding inherent tensions between them. Conflicts between economic and environmental objectives, in particular, have been noted as restraining efforts to instigate transitions to environmental sustainability, with growth ambitions limiting environmental policy to “win–win” cases. This paper argues that they can also play complementary roles in managing transitions by creating inclusive visions for rallying actors and resources. This is explored by looking at a case of sustainable regeneration in Wales, UK. Using as a case study the Arbed scheme, an area-based project established in 2009 to retrofit housing stock for energy efficiency, this paper shows how the scheme explicitly addresses economic, environmental and social aspects of sustainability; and, in particular, how sustainable development aims constituted a guiding vision that supported the formation of actor and resource networks necessary for large-scale retrofitting.  相似文献   
24.
Recognizing local people's priorities for tropical forest biodiversity   总被引:4,自引:0,他引:4  
Tropical forest people often suffer from the same processes that threaten biodiversity. An improved knowledge of what is important to local people could improve decision making. This article examines the usefulness of explicitly asking what is important to local people. Our examples draw on biodiversity surveys in East Kalimantan (Indonesian Borneo). With local communities we characterized locally valued habitats, species, and sites, and their significance. This process clarified various priorities and threats, suggested refinements and limits to management options, and indicated issues requiring specific actions, further investigation, or both. It also shows how biological evaluations are more efficient with local guidance, and reveals potential for collaborations between local communities and those concerned with conservation. Such evaluations are a first step in facilitating the incorporation of local concerns into higher-level decision making. Conservationists who engage with local views can benefit from an expanded constituency, and from new opportunities for pursuing effective conservation.  相似文献   
25.
The core element of the Costa Rican forestry policy is a financial instrument called the environmental service payment. This instrument rewards forest owners for the environmental services (the mitigation of greenhouse gases, the protection of watersheds and scenic beauty, and the development of biodiversity) their forests provide. In this article, the experiences with this new instrument are analyzed by focusing on the way interests are represented and access is granted, the openness of information exchange, whether social learning occurred, and whether decision-making authority is shared. The analysis is based on a survey conducted in the Huetar Norte Region and on in-depth interviews with the major stakeholders. The Costa Rican case indicates that financial instruments can be used to share responsibilities and that stakeholders can successfully cooperate on forest issues. It also shows that such a participatory approach is only promising if certain cultural, economic, organizational, and political conditions are met.  相似文献   
26.
Objective: In this study, we assessed the number of child passenger safety technicians (CPSTs) in Michigan over 4 years and characterized the CPST workforce in 2015 to identify factors associated with high productivity and longevity in the field.

Methods: We determined the number of CPSTs and those newly certified using lists from the Michigan Office of Highway Safety Planning (OHSP) from 2012 to 2015. We conducted a statewide survey of Michigan CPSTs in October 2015. Analyses were conducted in 2016. The survey assessed demographic characteristics, reasons to enter the field and maintain certification, and motivations to conduct seat checks. We used CPST-reported time devoted to seat checks and average number of seats checked per month to create a composite “activity level” variable. We examined activity levels across several characteristics.

Results: The number of CPSTs ranged from 941 to 980 over the study period, with approximately 200 new certifications annually. In 2015, surveys were started by 496 of 962 eligible CPSTs and 427 submitted complete responses. CPST-instructors had a higher response rate than CPSTs in general (89 vs. 49%, P < .0001). The majority of respondents were women (71%) and self-identified as white (88%). More than one third were 35–44 years old. Just 7% were comfortable checking seats using a language other than English. “Personal reasons” were most often cited motivation for becoming a CPST and maintaining certification. Natural fit/job enhancement were more common reasons to maintain certification than become a CPST. Time and distance had the greatest influence on seat check participation. Perceived need, appointments vs. drop-in, and employer factors were very influential for 10–15% of CPSTs. Few CPSTs considered free food and payments/giveaways very influential. About 40% of respondents were considered high-activity (>24 seats checked/year), one third medium-activity (5 to 24 seats checked/year), and one quarter low-activity (<5 seats checked/year). High-activity CPSTs most commonly reported both being paid and volunteering their time to check seats, worked with a Safe Kids coalition, worked in law enforcement or social services, and had recertified at least once. Motivation to participate in seat checks did not vary with activity level.

Conclusions: Understanding the demographic characteristics and motivations of CPSTs can help Michigan OHSP recruit and retain a workforce dedicated to increasing the safety of child passengers. Agencies hosting seat checks can use these results to align the strategies they employ to incentivize CPSTs to serve in their communities with the factors that have the greatest influence on CPST participation.  相似文献   

27.
Caste determination in primitively eusocial sweat bees is thought to be due to an interacting suite of factors, including size of the larval provision mass, time of year, and social context of the nest into which a young female emerges. Newly emerged gynes are significantly fatter than newly emerged workers, suggesting the existence of larval caste determination cues. Since photoperiod, temperature, and interactions with nestmates were unlikely to affect larval caste determination, we compared the sizes and contents of larval provision masses destined to produce either workers or gynes. Gyne-destined larvae consumed pollen masses that were larger and contained slightly more sugar than those of worker-destined larvae. We suggest that sugar content is one cue which prompts the development of fat reserves in gyne-destined females but not in worker-destined females. The amount of fat possessed by a newly emerged female influences her chances of successfully entering diapause shortly after emergence. Therefore, small, lean females may be more susceptible to behavioural control by queens and more likely to become workers, while large, fat females would be more likely to become gynes. Correspondence to: M.H. Richards  相似文献   
28.
This paper deals with the use of simplified methods to predict methane generation in tropical landfills. Methane recovery data obtained on site as part of a research program being carried out at the Metropolitan Landfill, Salvador, Brazil, is analyzed and used to obtain field methane generation over time. Laboratory data from MSW samples of different ages are presented and discussed; and simplified procedures to estimate the methane generation potential, Lo, and the constant related to the biodegradation rate, k are applied. The first order decay method is used to fit field and laboratory results. It is demonstrated that despite the assumptions and the simplicity of the adopted laboratory procedures, the values Lo and k obtained are very close to those measured in the field, thus making this kind of analysis very attractive for first approach purposes.  相似文献   
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