Determining the effects of habitat management and climate on the population trends of a declining steppe bird

The Little Bustard Tetrax tetrax is one of the most threatened steppe bird species in Europe, due mainly to agricultural intensification. Despite the relative importance of the Iberian population (approximately 50% of the global population) little is known about its dynamics and trends, especially in core distribution areas. This study evaluates the influences of meteorological factors and land management on the oscillations and medium-term trends of two Little Bustard populations in Central Spain. During 2001–2007, surveys of breeding male and female Little Bustards were carried out in two central Spanish locations: Valdetorres, in Special Protection Area (SPA) no. 139 (1600 ha), and Campo Real, in Important Bird Area (IBA) no. 075 (1150 ha). Densities were 3.3–4.0 and 1.1–2.1 males/km² in Campo Real, and 1.8–2.2 and 0.6–1.3 females/km² in Valdetorres. The sex ratio was biased towards males in both cases. Both populations declined during 2001–2007, especially in Valdetorres (60%). Variation in habitat composition did not explain variation in the numbers of males. Both populations were influenced by total precipitation in the preceding October–May period. Results suggest that the Little Bustard may be sensitive to future climate trends in Europe. Finally, different simulated demographic scenarios suggest that low female survival and productivity may be the immediate cause of the decline in Little Bustard populations, which is consistent with their sensitivity to climatic conditions.     

Compositional similarity among urban floras within and across continents: biogeographical consequences of human-mediated biotic interchange

Anthropogenic activities have weakened biogeographical barriers to dispersal resulting in the global spread and establishment of an increasing number of non‐native species. We examine the broad‐scale consequences of this phenomenon based on an analysis of compositional similarity across urban floras in the northeastern United States and Europe. We test the prediction that homogenization of species composition is uniquely defined within vs. between continents based on the time and place of origin of non‐native species. In this case, for archaeophytes and neophytes in Europe (introduced before and after ad 1500, respectively) and non‐native species originating from within and outside the United States. More species in urban floras were shared within than between continents. Within Europe, archaeophytes shared more species across urban floras compared with neophytes; strong associations were not observed for non‐native species across US urban floras. Between the two continents, non‐native species in the United States that originated from outside the United States shared species primarily with archaeophytes but also with European natives and neophytes. These results suggest that the direction of biotic interchange was unidirectional with species moving primarily from Europe to the United States with archaeophytes playing a primary and non‐native species originating from outside the two continents a secondary role as a homogenizing source. Archaeophytes, based on combination of biogeographical, evolutionary, and ecological factors in association with a long history of anthropogenic influence, appear to have played a prominent role in the continental and intercontinental homogenization of species composition. This suggests that the uniform homogenization of the Earth's biota is not imminent and is presently directed by a combination of biogeographically defined anthropogenic and historical factors.     

Population structure,diversity, and phylogeography in the near‐threatened Eurasian black vultures Aegypius monachus (Falconiformes; Accipitridae) in Europe: insights from microsatellite and mitochondrial DNA variation

The Eurasian black vulture (Aegypius monachus) has experienced a severe decline during the last two centuries and is globally classified as near‐threatened. This has led to the extinction of many traditional breeding areas in Europe and resulted in the present patchy distribution (Iberian and Balkan peninsulas) in the Western Palearctic. In the present study, we describe the current genetic status of the European populations using both mitochondrial cytochrome b sequences and nuclear microsatellite markers, comparing with those found in Asia (Mongolia and Caucasus region). Although, mitochondrial (mt)DNA revealed a relatively low genetic variability (haplotype diversity), no evidence of genome‐wide genetic erosion exists because nuclear diversity exhibits normal levels and strong differentiation. A highly philopatric dispersal behaviour must be invoked to explain the existence of a clear pattern that revealed by the phylogeographic analysis, which indicates a sharp East–West clinal distribution and an allopatric differentiation. The distribution of mtDNA haplotypes one in the Iberian population and two in Balkan population and the significance divergence at nuclear loci fulfill the definitions of those populations as evolutionary significant units. We discuss how management strategies should aim at the maintenance (or increase) of current genetic variability levels, suggesting that independent conservation plans are urgently required to protect these two breeding European populations from extinction. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 95 , 859–872.     

Assessing the taxonomic status of tropical frogs through bioacoustics: geographical variation in the advertisement calls in the Eleutherodactylus discoidalis species group (Anura)

The taxonomic status of a very poorly known group of Andean frogs (the Eleutherodactylus discoidalis group) is assessed through acoustic and statistical analyses of differences in temporal parameters of advertisement calls, such as the number of pulses and the call duration, and also in a spectral parameter, dominant frequency. As these species are usually misidentified or ignored because of their taxonomic complexity in both ecological and biodiversity studies, we provide a bioacoustical diagnosis for each species in order to facilitate identification in the field. Differences in acoustic parameters support the specific status of Eleutherodactylus cruralis , E. discoidalis , Eleutherodactylus ibischi , and Eleutherodactylus madidi . The name E. cruralis is probably applied to three different species: the nominal form from Amazonian forests of the Andean slopes and adjacent lowlands, and two cryptic species restricted to inter-Andean dry valleys and cloud forests from central Bolivia. Moreover, the distribution of energy through the call and the aggregation of pulses seem to be useful meristic characters for detecting interspecific differences. Populations from each macrohabitat can be recognized by distinctive advertisement calls, usually corresponding to a recognized species. For the whole group, pulse rate is significantly correlated to latitude, which could indicate a speciation process along the Andes in relation to habitat changes and isolation. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 353–365.     

香蕉束顶病毒基因Ⅰ的克隆及序列分析

以中国漳州地区感染ＢＢＴＶ的香蕉组织总ＤＮＡ为模板,根据我国台湾地区ＢＢＴＶ分离物基因组Ⅰ序列,设计并合成了一对引物,通过ＰＣＲ扩增出约５００ｂｐ的片段。利用ｐＢｌｕｅｓｃｒｉｐｔⅡＳＫ Ｔ－载体获得此片段的克隆,经测序表明为ＢＢＴＶ组分Ⅰ的部分序列。由已测知的ＢＢＴＶ基因组Ⅰ序列设计一对相邻引物,以我国漳州的感染ＢＢＴＶ香蕉组织总ＤＮＡ为模板,通过ＰＣＲ坟增出约１．１ｋｂ的片段。利用ｐＢｌｕｅｓ     

Physiological complexity and system adaptability: evidence from postural control dynamics of older adults

The degree of multiscale complexity in human behavioral regulation, such as that required for postural control, appears to decrease with advanced aging or disease. To help delineate causes and functional consequences of complexity loss, we examined the effects of visual and somatosensory impairment on the complexity of postural sway during quiet standing and its relationship to postural adaptation to cognitive dual tasking. Participants of the MOBILIZE Boston Study were classified into mutually exclusive groups: controls [intact vision and foot somatosensation, n = 299, 76 ± 5 (SD) yr old], visual impairment only (<20/40 vision, n = 81, 77 ± 4 yr old), somatosensory impairment only (inability to perceive 5.07 monofilament on plantar halluxes, n = 48, 80 ± 5 yr old), and combined impairments (n = 25, 80 ± 4 yr old). Postural sway (i.e., center-of-pressure) dynamics were assessed during quiet standing and cognitive dual tasking, and a complexity index was quantified using multiscale entropy analysis. Postural sway speed and area, which did not correlate with complexity, were also computed. During quiet standing, the complexity index (mean ± SD) was highest in controls (9.5 ± 1.2) and successively lower in the visual (9.1 ± 1.1), somatosensory (8.6 ± 1.6), and combined (7.8 ± 1.3) impairment groups (P = 0.001). Dual tasking resulted in increased sway speed and area but reduced complexity (P < 0.01). Lower complexity during quiet standing correlated with greater absolute (R = -0.34, P = 0.002) and percent (R = -0.45, P < 0.001) increases in postural sway speed from quiet standing to dual-tasking conditions. Sensory impairments contributed to decreased postural sway complexity, which reflected reduced adaptive capacity of the postural control system. Relatively low baseline complexity may, therefore, indicate control systems that are more vulnerable to cognitive and other stressors.     

原发性肝癌:CT血液供应、P53抗体和血管内皮生长因子

目的:分析原发性肝癌(primary hepatic carcinoma,简称肝癌)血液供应(blood supply,简称血供)CT类型与患者血清P53抗体、血管内皮生长因子(vascular endothelial growth factor,VEGF)的关系,以及血清P53抗体与VEGF的相关性.方法:用酶联免疫吸附法定量检测首诊肝癌患者血清P53抗体和VEGF,与CT诊断的血供类型结果进行对比,分析不同血供类型的肝癌是否存在血清P53抗体差异(单因素分析),并分析不同血供类型的肝癌血清VEGF是否存在差异(单因素分析),然后分析血清P53抗体和VEGF之间的相关性.结果:四种不同血供类型的肝癌之间血清P53抗体滴度有差异(P<0.05).值得注意的是,富血供型与混合型之间、动-静脉漏型(AVS)与混合型之间血清P53抗体有显著差异(P<0.05),富血供型与AVS型之间血清P53抗体没有显著差异(P>0.05).不同血供类型的肝癌中,富血供型和混合型血清P53抗体与VEGF呈正相关(P<0.05),而AVS型和乏血供型中,血清P53抗体与VEGF不呈直线相关(P>0.05).结论:血清P53抗体和血清VEGF滴度在血供不同肝癌中滴度有差异,在富血供型和混合型中血清P53抗体与VEGF滴度呈正相关.     

Lifestyle modifications to prevent and control hypertension. 1. Methods and an overview of the Canadian recommendations. Canadian Hypertension Society,Canadian Coalition for High Blood Pressure Prevention and Control,Laboratory Centre for Disease Control at Health Canada,Heart and Stroke Foundation of Canada

OBJECTIVE: To provide updated, evidence-based recommendations for health care professionals on lifestyle changes to prevent and control hypertension in otherwise healthy adults (except pregnant women). OPTIONS: For people at risk for hypertension, there are a number of lifestyle options that may avert the condition--maintaining a healthy body weight, moderating consumption of alcohol, exercising, reducing sodium intake, altering intake of calcium, magnesium and potassium, and reducing stress. Following these options will maintain or reduce the risk of hypertension. For people who already have hypertension, the options for controlling the condition are lifestyle modification, antihypertensive medications or a combination of these options; with no treatment, these people remain at risk for the complications of hypertension. OUTCOMES: The health outcomes considered were changes in blood pressure and in morbidity and mortality rates. Because of insufficient evidence, no economic outcomes were considered. EVIDENCE: A MEDLINE search was conducted for the period January 1996 to September 1996 for each of the interventions studied. Reference lists were scanned, experts were polled, and the personal files of the authors were used to identify other studies. All relevant articles were reviewed, classified according to study design and graded according to level of evidence. VALUES: A high value was placed on the avoidance of cardiovascular morbidity and premature death caused by untreated hypertension. BENEFITS, HARMS AND COSTS: Lifestyle modification by means of weight loss (or maintenance of healthy body weight), regular exercise and low alcohol consumption will reduce the blood pressure of appropriately selected normotensive and hypertensive people. Sodium restriction and stress management will reduce the blood pressure of appropriately selected hypertensive patients. The side effects of these therapies are few, and the indirect benefits are well known. There are certainly costs associated with lifestyle modification, but they were not measured in the studies reviewed. Supplementing the diet with potassium, calcium and magnesium has not been associated with a clinically important reduction in blood pressure in people consuming a healthy diet. RECOMMENDATIONS: (1) It is recommended that health care professionals determine the body mass index (weight in kilograms/[height in metres]2) and alcohol consumption of all adult patients and assess sodium consumption and stress levels in all hypertensive patients. (2) To reduce blood pressure in the population at large, it is recommended that Canadians attain and maintain a healthy body mass index. For those who choose to drink alcohol intake should be limited to 2 or fewer standard drinks per day (maximum of 14/week for men and 9/week for women). Adults should exercise regularly. (3) To reduce blood pressure in hypertensive patients, individualized therapy is recommended. This therapy should emphasize weight loss for overweight patients, abstinence from or moderation in alcohol intake, regular exercise, restriction of sodium intake and, in appropriate circumstances, individualized cognitive behaviour modification to reduce the negative effects of stress. VALIDATION: The recommendations were reviewed by all of the sponsoring organizations and by participants in a satellite symposium of the fourth international Conference on Preventive Cardiology. They are similar to those of the World Hypertension League and the Joint National committee, with the exception of the recommendations on stress management, which are based on new information. They have not been clinically tested. SPONSORS: The Canadian Hypertension Society, the Canadian Coalition for High Blood Pressure Prevention and Control, the Laboratory Centre for Disease Control at health Canada, and the Heart and Stroke Foundation of Canada.