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51.
To study migration performance and return rates of hatchery brown trout Salmo trutta smolts the first 5 months after release, 50 fish in each year (fork length, LF, 158–288 mm) were in two subsequent years tagged with acoustic transmitters and recorded by automatic listening stations in the River Nidelva (central Norway), its estuary and in the marine environment. More than half of the smolts became anadromous migrants (52% in 2011 and 70% in 2012). The fish spent longer time in the estuary than in the marine environment and the results suggest that migratory behaviour of S. trutta smolts is not only restricted to be resident or anadrome–lacustrine, but that there is also an intermediary strategy of estuarine feeding. There were no differences in LF or mass between groups of smolts with different migration patterns. Return rates from the sea within the first 5 months after release were in both years 16%. Median progression rate in the river was 0·090 LF s?1 but decreased significantly as the smolts entered the estuary (0·015 LF s?1). The long residential time in the estuary may increase the risk of negative effects of anthropogenic activities in estuaries, such as harbours and industrial development, and special attention should be given to evaluate effects of such activities.  相似文献   
52.
  • 1 European rabbits are considered a keystone species in the Iberian Peninsula. Their populations have sharply declined over the past century, mainly due to habitat loss and the arrival of two viral diseases: myxomatosis in the 1950s and rabbit haemorrhagic disease (RHD) at the end of the 1980s. For the conservation of the Iberian Mediterranean ecosystem, it is important to determine whether rabbit populations are recovering two decades after the RHD outbreak, and to identify the factors associated with population recovery.
  • 2 Here, we review the current knowledge on recent rabbit population trends in the Iberian Peninsula and the factors associated with these trends.
  • 3 Although most rabbit populations are still declining in the Iberian Peninsula, a few seem to have recovered. In general, positive trends have been recorded in species‐friendly habitats characterized by non‐fragmented landscapes, interspersed patches of Mediterranean scrubland, good pastures and/or crops, soft soils that are suitable for warren construction and a Mediterranean climate with relatively high rainfall. Additionally, rabbits seem to be recovering better in areas where management practices (e.g. low hunting pressure, habitat management and predator control) are applied to increase their numbers.
  • 4 From these findings, it is possible to identify five broad objectives for rabbit conservation in the Iberian Peninsula. First, it is clearly necessary to establish a long‐term programme for monitoring rabbit abundance and trends on a large scale. Second, the conservation and restoration of open Mediterranean scrubland should be a priority for stabilizing and maintaining existing healthy rabbit populations. Third, despite the lack of experimental evidence, management activities aimed at increasing the quantity and quality of both refuge and food should continue to be implemented. Fourth, legislation on the timing of the hunting season should be revisited following recommendations made by scientists. Finally, experimental approaches are required to investigate whether the control of generalist predators is a successful strategy to allow rabbit populations to recover.
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53.
Oleanolic acid, scoparone, scopoletin and a novel iridoid derivative, angelone, were isolated from Tachiadenus longiflorus (Gentianaceae). The structure of angelone was determined from NMR data, given as input to the Logic for Structure Determination Programme, and was finally confirmed by comparison of experimental 13C-NMR chemical shifts with those obtained by quantum mechanical calculations.  相似文献   
54.
In 1992 a stocking programme was established to re‐introduce North Sea houting Coregonus oxyrinchus , which disappeared from the River Rhine in the 1940s, in the Lower Rhine. Juvenile North Sea houting have been stocked since 2001 in a gravel pit lake permanently connected to the Lower Rhine, and in the Lippe, a potamal tributary of the Rhine. Monitoring studies showed that the majority of the small North Sea houting left the gravel pit lake within 4 days after stocking. In the Lippe, some of the juveniles were found in the drift immediately after stocking, generally preferring the middle surface areas of the river. Other North Sea houting waited until dawn before they started their downstream migration. Juveniles immediately started to feed on the zooplankton resources in both waters. Pond studies revealed high growth rates of juvenile North Sea houting, ranging from 0·44 to 0·94 mm day−1. This study suggests that the stocking strategies at both waters of the Lower Rhine comply with the requirements of the migration behaviour of juvenile North Sea houting.  相似文献   
55.
Extensive genetic progress has been achieved in dairy cattle populations on many traits of economic importance because of efficient breeding programmes. Success of these programmes has relied on progeny testing of the best young males to accurately assess their genetic merit and hence their potential for breeding. Over the last few years, the integration of dense genomic information into statistical tools used to make selection decisions, commonly referred to as genomic selection, has enabled gains in predicting accuracy of breeding values for young animals without own performance. The possibility to select animals at an early stage allows defining new breeding strategies aimed at boosting genetic progress while reducing costs. The first objective of this article was to review methods used to model and optimize breeding schemes integrating genomic selection and to discuss their relative advantages and limitations. The second objective was to summarize the main results and perspectives on the use of genomic selection in practical breeding schemes, on the basis of the example of dairy cattle populations. Two main designs of breeding programmes integrating genomic selection were studied in dairy cattle. Genomic selection can be used either for pre-selecting males to be progeny tested or for selecting males to be used as active sires in the population. The first option produces moderate genetic gains without changing the structure of breeding programmes. The second option leads to large genetic gains, up to double those of conventional schemes because of a major reduction in the mean generation interval, but it requires greater changes in breeding programme structure. The literature suggests that genomic selection becomes more attractive when it is coupled with embryo transfer technologies to further increase selection intensity on the dam-to-sire pathway. The use of genomic information also offers new opportunities to improve preservation of genetic variation. However, recent simulation studies have shown that putting constraints on genomic inbreeding rates for defining optimal contributions of breeding animals could significantly reduce achievable genetic gain. Finally, the article summarizes the potential of genomic selection to include new traits in the breeding goal to meet societal demands regarding animal health and environmental efficiency in animal production.  相似文献   
56.
Matt Hodges 《Ethnos》2013,78(3):348-374
‘Amateur’ anthropology and ethnography are utopian categories proposed by anthropologists seeking to critique a perceived culture of ‘professionalism’ within the discipline (Grimshaw &; Hart, 1993 Grimshaw, Anna and Hart, Keith. 1993. Anthropology and the Crisis of the Intellectuals, Cambridge: Prickly Pear Pamphlet No.1.  [Google Scholar]). Yet they have arguably been practised extensively by local intellectuals oblivious to such debates. In rural Europe, this has often involved ‘pastoral’ conservation of ‘local history’, ‘traditions’ and ‘folk customs’, in the context of identity politics. Recent manifestations, however, have enabled the disciplining of cultural practices of indigenous populations by local entrepreneurs for use in heritage tourism. Building on Foucault's concept of a ‘disciplinary programme’, this paper analyses projects from a French Mediterranean village that have ‘borrowed’ discursive forms from French ethnology and historiography to convert local heritages into disciplined archives and booklets, predominantly for use in tourism. It then analyses their approximation to the discipline of anthropology; assesses their problematic distinction from anthropology's own disciplinary programmes; and explores the implications.  相似文献   
57.
Cho EP  Hwang SJ  Clovis JB  Lee TY  Paik DI  Hwang YS 《Gerodontology》2012,29(2):e972-e980
doi: 10.1111/j.1741‐2358.2011.00594.x Enhancing the quality of life in elderly women through a programme to improve the condition of salivary hypofunction Objective: The purposes of this study were to examine the effects of oral exercise intended to improve the function of the oral cavity in the elderly and their quality of life to pave the way for the development of oral‐health promotion programmes geared towards the elderly. Methods: The subjects were 78 female Koreans who resided in Seoul and were aged 65 years and older. During a 3‐month period, an oral function promotion programme was conducted twice a week, between 10.00 am and 12.00 pm , applying oral exercise suggested by a Japanese public health centre. A survey was conducted by interviewing the selected women to determine the state of their subjective dry mouth, quality of life related to oral health and jaw functional limitation. Their opening, unstimulated whole saliva and pronunciation speed were measured before and after the oral function exercise programme. Results: The subjects showed a significant improvement in subjective dry mouth symptoms, relevant behaviour, the level of discomfort caused by dry mouth and subjective jaw functional limitation during mastication and swallowing and emotional expression after receiving the oral exercise. After the oral exercise, there was a significant increase in mouth opening, unstimulated whole saliva and speaking speed (‘patakala’ pronunciation) after oral exercise. There was also significant progress in their quality of life related to oral health. Overall improvement in subjective dry mouth symptoms and relevant behaviour over time after oral exercise had a positive correlation with the level of improvement in discomfort triggered by dry mouth and mastication. The level of improvement in OHIP‐14 had a positive correlation with the level of overall improvement in dry mouth symptoms and behaviour, the level of improvement in discomfort by dry mouth and that in mastication and swallowing. Conclusion: This study showed the effects of the oral function promotion programme and correlation of oral condition and oral health‐related quality of life. It is suggested that this oral function promotion programme has positive effects on both objective and subjective oral conditions. It is strongly recommended that this programme, along with other oral health promotion programmes, be implemented to improve oral function and oral health‐related quality of life for the elderly.  相似文献   
58.
Inbreeding and the loss of genetic diversity may lower fitness and reduce the potential for a population to adapt to changing environments. In small populations, for example in captive populations or populations of endangered species, this can have considerable consequences for their survival. We investigated the effects of inbreeding on infant mortality in the world captive population of bonobos Pan paniscus . Using a combination of studbook data and high-quality pedigree data from genotyped individuals, inbreeding information was available for 142 captive-born individuals. For the determination of paternities that were unresolved in the studbook, nuclear microsatellite DNA was amplified from hair and blood samples using the Great Ape Kit and PowerPlex® 16 System. In total, 54 bonobos (17 offspring and their putative parents) were genotyped at eight tetranucleotide repeat microsatellite loci. Inbreeding coefficients were calculated for each individual for whom paternity was confirmed by either studbook data or DNA analysis. We found significantly higher infant mortality in inbred offspring compared with non-inbred offspring, suggesting that inbreeding reduces infant survival in captive bonobos. In addition, we argue that the total magnitude of inbreeding depression is probably underestimated in this captive population. In conclusion, even though the breeding programme of captive bonobos is aimed at avoiding inbreeding, closely related individuals do occasionally produce offspring that do show inbreeding depression. There is, however, no indication that this currently threatens the long-time survival of the captive population of bonobos.  相似文献   
59.
Characterization of resistance response to pathogens is a fundamental strategy in plant breeding programmes. Thus, in this study, we developed an effective inoculation method for resistance tests of bacterial halo blight (BHB), caused by Pseudomonas syringae pv. garcae on coffee. Firstly, aggressiveness of eight selected bacterial strains as well as seven mixed strains was assessed on coffee seedlings of Mundo Novo IAC 376‐4 cultivar. Two experiments were conducted comparing three inoculation techniques: initially, we compare the methods of sprinkling and multiple needles on four cultivars of Coffea arabica; later, four cultivars and seven genotypes were compared for the multiple needles method and the abrasion technique. Severity was evaluated according a disease rating scale (DRS), considering either leaf surface area affected for sprinkling, or affected inoculated area for inoculation by multiple needles and abrasion. The area under the disease progress curve of disease (AUDPC) was calculated considering weekly evaluations of disease from seven until 42 days postinoculation (DPI). The standard deviation (SD), coefficient of variation (CV) and confidence interval (CI) variables were used to denote the effectiveness of the methods. According to the results, strain IBSBF 1197 was the most aggressive, and three other strains showed high aggressiveness. All inoculation methods were able to discriminate the resistance response to BHB, wherein the sprinkling method was less efficient than multiple needles and abrasion technique was more efficient than multiple needles. In addition, disease evaluations at 14 DPI showed a high correlation coefficient with area under AUDPC at 42 DPI, validating the early selection to BHB. Results of inoculation methods indicated the abrasion on first pair of leaves, together with evaluations on fourteenth DPI, as the most promising technique for early selection on coffee breeding to BHB.  相似文献   
60.
  • 1 To contribute to the development of IPM strategies in olive groves, the selectivity of several insecticides to Pullus mediterraneus Fabr. (Coleoptera: coccinellidae) was investigated in the laboratory. The study assessed the toxicity of seven chemical pesticides and one bacteriological insecticide to adult P. mediterraneus.
  • 2 The LC50 was estimated by applying the pesticides on the dorsal side of adults. Lambda‐cyhalothrin, methomyl and cypermethrin resulted in the highest toxicity followed, in decreasing order of toxicity, by malathion, fenthion and dimethoate. Parathion had the least effect on the coccinellid.
  • 3 Consumption of Bacillus thuringiensis bacteria (applied as a commercial formulation), over a period of 10 consecutive days, resulted in low mortality of adult P. mediterraneus.
  • 4 The results of these laboratory experiments indicate that the most widely used chemical pesticides were toxic to P. mediterraneus. Their use in olive groves must take account of the activity period of this predator. In contrast, B. thuringiensis seemed to be a suitable candidate to be included in pest management systems.
  相似文献   
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