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41.
Two culicoides-borne diseases, Bluetongue (BTV) and Schmallenberg, have emerged in the European cattle population since 2006. Other diseases transmitted by these vectors could emerge. This justifies the development of syndromic surveillance programs whereby one or several indicators would be routinely monitored for the early detection of emerging diseases. The aim of this study was to evaluate milk yield from milk recording in dairy cattle as an indicator to be included in an emerging disease surveillance system. It was hypothesized that emergences would result in episodes of low milk production clustered in space and time. The 2007 BTV epizootic in France was used as a case study. Because it had already emerged in neighbouring countries, the disease emergence was expected and notification was mandatory. Herd-test-day milk productions were predicted for the entire country for 2006 and 2007 from herd historical data using linear mixed models. The differences between observed and predicted milk productions were averaged per week and per municipality and used as input for a space-time prospective scan statistic. Log likelihood ratios (LLR) associated with clusters were used to define alarms. The threshold chosen was a trade-off between detection timeliness and the number of false alarms per week. The first four BTV notifications occurred on the 12th (two notifications), 13th and 27th of July 2007. The 12th of July was considered to be the date of emergence. Alarms occurring before the 1st of March 2007 were considered to be false alarms. Using an LLR of 50, there were an average of 1.7 false alarms per week and the BTV emergence was detected seven weeks after emergence. Using an LLR of 100, there were an average of 0.8 false alarms per week and the BTV emergence was detected 9 weeks after emergence. Detection may have been delayed because of a discontinuation of milk recording between mid-July and mid-August. The first cluster with an LLR > 100 located in the emergence area was further investigated. A difference between observed and predicted production of >1 kg/cow/day was observed around the time of emergence. However, a difference of equal magnitude was observed during the year preceding the outbreak. Milk production predicted from herd history alone did not allow the detection of the 2007 BTV emergence in France. Further research should be conducted on improving the prediction of test-day milk yield and on combining it with other indicators based on routinely collected data.  相似文献   
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The application of the ecosystem services (ES) concept in land use planning has great potential to enhance the awareness of planning actors on their interactions. At the same time it can contribute to improve the linkage between the role of land use patterns and the understanding of land system functioning and its contribution to human well-being. The concept should be developed in a way that can be applicable in socio-ecological systems where nature and society are capable of enhancing their roles mutually. The objective of this paper is to suggest a standardized scheme and generalizable criteria to assess how successful the application of the ES concept contributed to facilitate participatory planning. We consider three potential advantages and three critical aspects for how to improve the applicability and relevance of the ES concept in planning. Hereon based, we present a balanced score card tool for which we broke down to advantages and risks into concrete questions. We illustrate the application of this approach with two case studies, representatives of two major governance schemes in relation to land use planning. We demonstrate that the balanced score card approach helps to reveal potential imbalances regarding the consideration of different ES groups. It supports testing the potential of the ES concept to enhance or not interactions of local and regional actors. We conclude that the framework should be reconsidered after a set of case studies to be developed into a monitoring tool for supporting planning practices.  相似文献   
44.
Landscape Ecology - Several case studies investigated the role of ecosystem services in participatory planning processes. However, no systematic study exists that cuts across a large number of...  相似文献   
45.
IGF-1 plays a key role in the proliferation and differentiation of granulosa cells. However, the molecular mechanism of IGF-1 action in avian granulosa cells during follicle maturation is unclear. Here, we first studied IGF-1 receptor (IGF-1R) expression, IGF-1-induced progesterone production and some IGF-1R signaling pathways in granulosa cells from different follicles. IGF-1R (mRNA and protein) was higher in fresh or cultured granulosa cells from the largest follicles (F1 or F2) than in those from smaller follicles (F3 or F4). In vitro, IGF-1 treatment (10(-8)M, 36h) increased progesterone secretion by four-fold in mixed F3 and F4 (F3/4) granulosa cells and by 1.5-fold in F1 granulosa cells. IGF-1 (10(-8)M, 30min)-induced increases in tyrosine phosphorylation of IGF-1R beta subunit and phosphorylation of ERK were higher in F1 than in F3/4 granulosa cells. Interestingly, IGF-1 stimulation (10(-8)M, 10min) decreased the level of AMPK Thr172 phosphorylation in F1 and F3/4 granulosa cells. We have recently showed that AMPK (AMP-activated protein kinase) is a protein kinase involved in the steroidogenesis in chicken granulosa cells. We then studied the effects of AMPK activation by AICAR (5-aminoimidazole-4-carboxamide ribonucleoside), an activator of AMPK, on IGF-1-induced progesterone secretion by F3/4 and F1 granulosa cells. AICAR treatment (1mM, 36h) increased IGF-1-induced progesterone secretion, StAR protein levels and decreased ERK phosphorylation in F1 granulosa cells. Opposite data were observed in F3/4 granulosa cells. Adenovirus-mediated expression of dominant negative AMPK totally reversed the effects of AICAR on IGF-1-induced progesterone secretion, StAR protein production and ERK phosphorylation in both F3/4 and F1 granulosa cells. Thus, a variation of energy metabolism through AMPK activation could modulate differently IGF-1-induced progesterone production in F1 and F3/4 granulosa cells.  相似文献   
46.
OBJECTIVE: To evaluate responses to self-administered brief questions regarding consumption of vegetables and fruit by comparison with blood levels of serum carotenoids and red-cell folate. DESIGN: A cross-sectional study in which participants reported their usual intake of fruit and vegetables in servings per day, and serum levels of five carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin and lycopene) and red-cell folate were measured. Serum carotenoid levels were determined by high-performance liquid chromatography, and red-cell folate by an automated immunoassay system. SETTINGS AND SUBJECTS: Between October and December 2000, a sample of 1598 adults aged 25 years and over, from six randomly selected urban centres in Queensland, Australia, were examined as part of a national study conducted to determine the prevalence of diabetes and associated cardiovascular risk factors. RESULTS: Statistically significant (P<0.01) associations with vegetable and fruit intake (categorised into groups: /=4 servings per day) were observed for alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin and red-cell folate. The mean level of these carotenoids and of red-cell folate increased with increasing frequency of reported servings of vegetables and fruit, both before and after adjusting for potential confounding factors. A significant association with lycopene was observed only for vegetable intake before adjusting for confounders. CONCLUSIONS: These data indicate that brief questions may be a simple and valuable tool for monitoring vegetable and fruit intake in this population.  相似文献   
47.
A procedure developed for soybean protein precipitation which was based on electrodialysis was tested for the production of acid casein from reconstituted skim milk. In a previous paper, the performance of bipolar membrane electroacidification (BMEA) was evaluated under different conditions of ionic strength (micro(added) = 0, 0.25, 0.5, or 1.0 M) and added salt (CaCl(2), NaCl, or KCl) (1). The aim of this study, which is the complement of the work on evaluation of BMEA performance, was to evaluate the functionality of the protein isolates produced by BMEA and to compare the BMEA isolates to commercial isolates and an isolate produced by chemical acidification. It was not possible to show differences between the functional properties of isolates produced by BMEA, except at 1 M CaCl(2) micro(added), due to the variability of the isolates. However, the results showed that it is possible to obtain isolates similar to commercial isolates and that the addition of salt during the process does not induce variations in functional properties. From results on mineral concentrations, it appeared that the addition of monovalent cations did not influence the retention of monovalent or divalent cations in the BMEA isolates, while addition of divalent cations (CaCl(2)) influenced the retention of magnesium. According to previous results on evaluation of BMEA performances under different conditions of ionic strength and added salt, the difference observed for the BMEA isolate produced at 1.0 M CaCl(2) was confirmed.  相似文献   
48.
Objective To measure the plasma fentanyl concentrations achieved over time with transdermal fentanyl patches in awake cats and cats undergoing anesthesia and ovariohysterectomy. Study design Randomized prospective experimental study. Animals Twenty‐four purpose‐bred cats. Methods Cats were randomly assigned to three groups for Part I of a larger concurrent study. Group P received only a 25 μg hour?1 transdermal fentanyl patch. Group P/A received the patch and anesthesia. Group A received only anesthesia. After a minimum 1‐week washout period, the cats were randomly reassigned to two groups for Part II of the larger study. Group P/A/O received the patch, anesthesia and ovariohysterectomy. Group A/O received anesthesia and ovariohysterectomy. Patches were left in place for 72 hours and plasma samples were obtained for fentanyl analysis while the patches were in place, and for 8 hours after patch removal for cats in Group P, P/A, and P/A/O. Results The 25 μg hour?1 transdermal fentanyl patches were well tolerated by the cats in this study (mean body weight of 3.0 kg) and no overt adverse effects were noted. Mean plasma fentanyl concentrations over time, mean plasma fentanyl concentrations at specific times (8, 25, 49, and 73 hours after patch placement), time to first detectable plasma fentanyl concentration, time to reach maximum plasma fentanyl concentration, maximum plasma fentanyl concentration, mean plasma fentanyl concentration from 8 to 73 hours, elimination half‐life, and total area under concentration (AUC) were not statistically different among the groups. Conclusions Halothane anesthesia and anesthesia/ovariohysterectomy did not significantly alter the plasma fentanyl concentrations achieved or pharmacokinetic parameters measured, when compared with awake cats. There was a high degree of individual variability observed both within and between groups of cats in parameters measured. Clinical significance The high degree of variability observed suggests that careful observation of cats with fentanyl patches in place is required to assess efficacy and any potential adverse effects. Anesthesia and anesthesia/ovariohysterectomy do not appear to alter plasma fentanyl concentrations achieved by placement of a 25 μg hour?1 transdermal fentanyl patch when compared to cats not undergoing these procedures.  相似文献   
49.
Ex vivo whole blood stimulation with endotoxin has proved to be a useful method for quantitative evaluations of the pro-inflammatory cytokine tumor necrosis factor alpha (TNF-alpha) response ability in humans. In the present study, a dose- and time-response study was carried out in order to develop an ex vivo whole blood stimulation assay for the quantification of TNF-alpha production in pigs. The TNF-alpha response was enhanced with increasing endotoxin stimulation dose. The maximum TNF-alpha response occurred after 2-8 h of stimulation. Subsequently, the assay was used to evaluate the TNF-alpha response in pigs (n=32) in relation to weaning. The TNF-alpha response was 332 pg ml(-1) (+/-59 pg) plasma 2 days before weaning and 127 pg ml(-1) (+/-23 pg) plasma 2 days after weaning, which was a significant reduction (p<0.001). Total and differential counts of leucocytes were the same before and after weaning. Thus the lower TNF-alpha response may be due to reduced monocyte responsiveness to the endotoxin, rather than caused by a reduction in monocyte numbers. The reduced TNF-alpha response in piglets after weaning may be a factor of importance to the increased disease susceptibility seen in piglets in this period.  相似文献   
50.
On irrigated agricultural soils from semi-arid and arid regions, ammonia (NH3) volatilization and nitrous oxide (N2O) emission can be a considerable source of N losses. This study was designed to test the capture of 15N loss as NH3 and N2O from previous and recent manure application using a sandy, calcareous soil from Oman amended one or two times with 15N labeled manure to elucidate microbial turnover processes under laboratory conditions. The system allowed to detect 15N enrichments in evolved N2O-N and NH3-N of up to 17% and 9%, respectively, and total N, K2SO4 extractable N and microbial N pools from previous and recent 15N labeled manure applications of up to 7%, 8%, and 15%. One time manured soil had higher cumulative N2O-N emissions (141 µg kg?1) than repeatedly manured soil with 43 µg kg?1 of which only 22% derived from recent manure application indicating a priming effect.  相似文献   
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