Protected Areas, Subsistence Farming Systems and Nature Conservation     

Luis Tiberio  Filipa Manso  Ana  Marta-Costa Carlos  Fonseca Aurora  Monzon 《农业科学与技术》2012,(3):402-411

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Evaluation of Total and Faecal Coliforms and Salmonella spp. in Irradiated Mussels from Brazil     

Flaivia Aline Andrade Calixto  Eliana de Faitima Marques de Mesquita  Robson Maia Franco  Cynthia Annes Rubiao  Neila Mello dos Santos Cortez  Mauro Carlos Lopes Souza  Licinio Esmeraldo da Silva 《农业科学与技术》2012,(4):511-519

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Temporal dynamics of root and foliar severity of soybean sudden death syndrome at different inoculum densities     

Carlos Gongora-Canul  Forrest W. NutterJr  Leonor Frazao S. Leandro 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(1):71-79

Temporal dynamics of soybean sudden death syndrome (SDS) root and foliar disease severity were studied in growth chamber experiments on susceptible plants exposed to different inoculum densities (0, 10⁰, 10¹, 10², and 10³ conidia g⁻¹ soil) of Fusarium virguliforme. The monomolecular model provided the best fit to describe the progress of root and foliar disease severity over time. Disease severity and area under disease progress curve (AUDPC) both increased in response to increasing inoculum density (P < 0.01), particularly for foliar symptoms. Rate of disease progress increased as inoculum densities increased for both root and foliar disease severities. The incubation period for root and foliar disease severity ranged from 9 to 18 and 15 to 25 days, respectively. Significant differences in root rot severity were most easily detected during the early stages of infection, whereas root rot and foliar severities were only weakly correlated when both were assessed simultaneously at later stages of disease development. Root rot severity assessments performed 15 to 20 days after inoculation (DAI) were most highly correlated (r > 0.9, P < 0.01) with foliar disease severity assessments performed 30 to 50 DAI. Root biomass was reduced by up to 67% at the three highest inoculum densities, indicating the aggressiveness that F. virguliforme possesses as a root rot pathogen on soybeans.  相似文献   

全球大鸨的现状及种群发展趋势     

Juan C.ALONSO  Carlos PALACN 《中国鸟类》2010,1(2):141-147

2010年大鸨的全球种群数量估计为44100-57000只,其中57-70%分布于西班牙,俄罗斯的欧洲部分占15-25%,中国、蒙古及俄罗斯东南部共占4-10%,葡萄牙占3-4%,匈牙利占3%,土耳其占1-2%,其余零星分布于其他10个国家.在这次估算和调查结果中,大部分统计数据(占全球种群数量的67-75%)的可靠性很高,其余25-33%(分布于俄罗斯、蒙古国、中国、土耳其、乌克兰、伊朗、哈萨克斯坦等国家)或因调查不完善或因数据陈旧导致可靠性较低.虽然有报道称部分国家(如土耳其、伊朗和中国)的大鸨种群数量持续下降,但本次调查表明,在过去的10年里,全球种群数量并没有明显减少,与目前有关全球种群数量呈下降趋势的预测恰恰相反.这是由于近些年在大鸨主要分布区(如西班牙、葡萄牙)开展了全面、稳定的调查,使结果更准确;且在这些国家制定禁捕令后的几十年里,大鸨数量有明显恢复.仅在生活着全球大鸨总数的6-10%的地区,种群数量仍存在明显下降的现象,这主要是由于农业活动加剧以及栖息地退化、非法捕猎、触碰高压线等原因造成的.只有极少部分(占全球种群数量的3-4%)因管理和保护措施得当,种群数量有明显的(德国、奥地利)或显著的(匈牙利)增加.占全球总数的19-22%因当前或过去的调查不准确,现状和种群发展趋势不明确.因此,我们建议:1)继续保护该物种以及对全球现状的关注;2)为更准确地估算大鸨全球数量和趋势,应在种群资料相对缺乏的国家尽快展开全国性的调查.  相似文献   

Otolith geochemistry in young‐of‐the‐year peacock bass Cichla temensis for investigating natal dispersal in the Rio Negro (Amazon – Brazil) river system          下载免费PDF全文

Raniere C. S. Garcez  Robert Humston  David Harbor  Carlos E. C. Freitas 《Ecology of Freshwater Fish》2015,24(2):242-251

This study examined otolith geochemistry as a natural marker of natal origins in young‐of‐the‐year (YOY) Cichla temensis in the Negro River Basin of Brazil. We analysed trace element and isotopic composition of otoliths of YOY collected off spawning nests from the main stem and major tributaries. These were compared with regional bedrock geologic composition to explore underlying mechanisms of differences in otolith geochemistry. Our results suggest that spatial differences in otolith geochemistry can be used to distinguish natal origins based on ⁸⁷Sr/⁸⁶Sr, Sr/Ca and Ba/Ca ratios. This approach allowed us to correctly classify 99% of juvenile fish to their natal streams using cross‐validation in a linear discriminant function analysis (LDFA). Patterns of otolith isotopic composition correspond with patterns in regional geology as expected based on previously demonstrated correlations, although some fine‐scale spatial differences cannot be accounted for by available geologic information. These results demonstrate that otolith chemistry is valuable as a natural marker of natal origins in this system and suggest that inferences from geologic maps may be useful for interpreting movements based on otolith geochemical signatures. This information provides the basis for future work to investigate the early life history and spatial ecology of this important cichlid.  相似文献   

Brown trout redd superimposition in relation to spawning habitat availability     

Javier Gortázar  Carlos Alonso  Diego García de Jalón 《Ecology of Freshwater Fish》2012,21(2):283-292

Abstract – The relationship between redd superimposition and spawning habitat availability was investigated in the brown trout (Salmo trutta L.) population inhabiting the river Castril (Granada, Spain). Redd surveys were conducted in 24 river sections to estimate the rate of redd superimposition. Used and available microhabitat was evaluated to compute the suitable spawning habitat (SSH) for brown trout. After analysing the microhabitat characteristics positively selected by females, SSH was defined as an area that met all the following five requirements: water depth between 10 and 50 cm, mean water velocity between 30 and 60 cm s^?1, bottom water velocity between 15 and 60 cm s^?1, substrate size between 4 and 30 mm and no embeddedness. Simple regression analyses showed that redd superimposition was not correlated with redd numbers, SSH or redd density. A simulation‐based analysis was performed to estimate the superimposition rate if redds were randomly placed inside the SSH. This analysis revealed that the observed superimposition rate was higher than expected in 23 of 24 instances, this difference being significant (P < 0.05) in eight instances and right at the limit of statistical significance (P = 0.05) in another eight instances. Redd superimposition was high in sections with high redd density. High superimposition however was not exclusive to sections with high redd density and was found in moderate‐ and low‐redd‐density sections. This suggests that factors other than habitat availability are also responsible for redd superimposition. We argue that female preference for spawning over previously excavated redds may be the most likely explanation for high superimposition at lower densities.  相似文献   

The partial substitution of digestible protein with gelatinized starch as an energy source reduces susceptibility to lipid oxidation in rainbow trout (Oncorhynchus mykiss) and sea bass (Dicentrarchus labrax) muscle     

Alvarez MJ  López-Bote CJ  Diez A  Corraze G  Arzel J  Dias J  Kaushik SJ  Bautista JM 《Journal of animal science》1999,77(12):3322-3329

We evaluated the influence of dietary gelatinized starch and protein on the fatty acid composition of muscle in rainbow trout and European sea bass and on the susceptibility of flesh to lipid peroxidation. The possibility that flesh peroxidation could be accounted for by lipogenesis and the deposition of fat was also explored. The inclusion of gelatinized starch in the diet of rainbow trout improved growth with respect to that observed in fish fed crude starch (P<.001). This was especially noticeable at the lowest concentration of dietary protein tested (P = .037); suggesting that gelatinized starch may partially replace protein in the production of energy without inducing a negative effect on growth. However, in European sea bass, the gelatinization of starch and dietary protein concentration showed no significant effect on final body weight. The intramuscular neutral lipid concentration of the sea bass was reduced by the gelatinization of dietary starch (P = .034). The highest dietary protein concentration increased the proportion of saturated fatty acids in the neutral (P = .0742) and polar (P = .0033) lipid fractions. The dietary inclusion of high levels of protein in rainbow trout led to a lower concentration of total (n-3) (P = .0457) and (n-6) (P = .0522) fatty acids and a higher concentration of total monounsaturated fatty acids (P = .0006). The inclusion of gelatinized starch led to a lower concentration of (n-3) fatty acids (P = .0034) and a higher concentration of saturated fatty acids (P = .0007). The polar fraction was hardly affected by the same treatment. A significantly lower susceptibility of the dorsal muscle to oxidation was observed in groups of European sea bass fed gelatinized starch (P<.01). A similar trend was observed in rainbow trout, although differences were not significant. The findings suggest that the digestible protein concentration of nutrient-dense diets for rainbow trout and European sea bass can be reduced with a beneficial effect on tissue lipid oxidation and no negative effects on growth and muscle composition.  相似文献   

Sedative and anticonvulsant effects of hydroalcoholic extract of Equisetum arvense     

Dos Santos JG  Blanco MM  Do Monte FH  Russi M  Lanziotti VM  Leal LK  Cunha GM 《Fitoterapia》2005,76(6):508-513

The hydroalcoholic extract of Equisetum arvense (HAE) tested at the doses of 200 and 400 mg/kg showed a significant activity on the open-field, enhanced the number of falls in the rota-rod reducing the time of permanence in the bar and increased the sleeping time (46% and 74%) in the barbiturate-induced sleeping time. In the pentylenetetrazole-seizure, it increased the first convulsion latency, diminished the severity of convulsions, reduced the percentage of animals which developed convulsion (50% and 25%) and protected animals from death. On the contrary, in the elevated plus maze, the doses 50, 100 and 150 mg/kg did not affect the evaluated parameters. Thus, HAE presented anticonvulsant and sedative effects. Phytochemical analysis detected the presence of tannins, saponins, sterols and flavonoids.  相似文献   

Metabolism of antioxidant and chemopreventive ellagitannins from strawberries, raspberries, walnuts, and oak-aged wine in humans: identification of biomarkers and individual variability     

Cerdá B  Tomás-Barberán FA  Espín JC 《Journal of agricultural and food chemistry》2005,53(2):227-235

Ellagitannins (ETs) are dietary polyphenols, containing ellagic acid (EA) subunits, with antioxidant and cancer chemopreventive activities that might contribute to health benefits in humans. However, little is known about their metabolic fate. We investigate here the metabolism of different dietary ETs and EA derivatives in humans. Forty healthy volunteers were distributed in four groups. Each group consumed, in a single dose, a different ET-containing foodstuff, i.e., strawberries (250 g), red raspberries (225 g), walnuts (35 g), and oak-aged red wine (300 mL). After the intake, five urine fractions (F) were collected at 8 (F1), 16 (F2), 32 (F3), 40 (F4), and 56 (F5) h. Neither ETs nor EA were detected in urine after LC-MS/MS analysis. However, the microbial metabolite 3,8-dihydroxy-6H-dibenzo[b,d]pyran-6-one (urolithin B) conjugated with glucuronic acid was detected along the fractions F3-F5 in all of the subjects, independently of the consumed foodstuff. The mean percentage of metabolite excretion ranged from 2.8 (strawberries) to 16.6% (walnuts) regarding the ingested ETs. Considerable interindividual differences were noted, identifying "high and low metabolite excreters" in each group, which supported the involvement of the colonic microflora in ET metabolism. These results indicate that urolithin B (a previously described antiangiogenic and hyaluronidase inhibitor compound) is a biomarker of human exposure to dietary ETs and may be useful in intervention studies with ET-containing products. The antioxidant and anticarcinogenic effects of dietary ETs and EA should be considered in the gastrointestinal tract whereas the study of potential systemic activities should be focused on the bioavailable urolithin B derivatives.  相似文献   

Use of quantitative two-dimensional color tissue Doppler imaging for assessment of left ventricular radial and longitudinal myocardial velocities in dogs   总被引：5，自引：0，他引：5  

Chetboul V  Sampedrano CC  Concordet D  Tissier R  Lamour T  Ginesta J  Gouni V  Nicolle AP  Pouchelon JL  Lefebvre HP 《American journal of veterinary research》2005,66(6):953-961

OBJECTIVE: To determine left ventricular free wall (LVFW) radial and longitudinal myocardial contraction velocities in healthy dogs via quantitative 2-dimensional color tissue Doppler imaging (TDI). ANIMALS: 100 dogs. PROCEDURE: TDI was used by a single trained observer to measure radial and longitudinal myocardial movement in the LVFW. Radial myocardial velocities were recorded in segments in the endocardial and epicardial layers of the LVFW, and longitudinal velocities were recorded in segments at 3 levels (basal, middle, apical) of the LVFW. RESULTS: LVFW velocities were higher in the endocardial layers than in the epicardial layers. Left ventricular free wall velocities were higher in the basal segments than in the middle and apical segments. Radial myocardial velocity gradients, defined as the difference between endocardial and epicardial velocities, were (mean +/- SD) 2.5 +/- 0.8 cm/s, 3.8 +/- 1.5 cm/s, and 2.3 +/- 0.9 cm/s in systole, early diastole, and late diastole, respectively. Longitudinal myocardial velocity gradients, defined as the difference between basal and apical velocities, were 5.9 +/- 2.2 cm/s, 6.9 +/- 2.5 cm/s, and 4.9 +/- 1.7 cm/s in systole, early diastole, and late diastole, respectively. A breed effect was detected for several systolic and diastolic TDI variables. In all segments, systolic velocities were independent of fractional shortening. CONCLUSIONS AND CLINICAL RELEVANCE: LVFW myocardial velocities decreased from the endocardium to the epicardium and from base to apex, thus revealing intramyocardial radial and longitudinal velocity gradients. These indices could enhance conventional echocardiographic analysis of left ventricular function in dogs. Breed-specific reference intervals should be defined.  相似文献