Wildcat population density in NE Portugal: A regional stronghold for a nationally threatened felid

Population density data on depleted and endangered wildlife species are essential to assure their effective management and, ultimately, conservation. The European wildcat is an elusive and threatened species inhabiting the Iberian Peninsula, with fragmented populations and living in low densities. We fitted spatial capture–recapture models on camera-trap data, to provide the first estimate of wildcat density for Portugal and assess the most influential drivers determining it. The study was implemented in Montesinho Natural Park (NE Portugal), where we identified nine individuals, over a total effort of 3,477 trap-nights. The mean density estimate was 0.032 ± 0.012 wildcat/km², and density tended to increase with distance to humanized areas, often linked to lower human disturbance and domestic cat presence, with forest and herbaceous vegetation cover and with European rabbit abundance. Although, this density estimate is within the range of values estimated for protected areas elsewhere in the Iberian Peninsula, our estimates are low at the European level. When put in context, our results highlight that European wildcats may be living in low population densities across the Iberian Mediterranean biogeographic region. No phenotypic domestic or hybrid cats were detected, suggesting potentially low admixture rates between the two species, although genetic sampling would be required to corroborate this assertion. We provide evidence that Montesinho Natural Park may be a suitable area to host a healthy wildcat population, and thus be an important protected area in this species' conservation context.     

县域城镇空间形态与居住建筑能耗关联性的连续尺度研究——以浙江长兴、福建连江为例

居住建筑能耗受建筑周边空间形态的直接影响，确定空间形态低碳效应及其最佳尺度将有助于实现县域城镇低碳转型。以浙江省长兴县、福建省连江县为例，共计选取49个具有代表性的居住建筑样本，采用GIS分析与数理统计相结合的方式，在居住建筑1800m半径范围内，以200m为间隔建立缓冲区，开展全年、最冷月份能耗期及最热月份能耗期建筑能耗与周边空间形态关联性的连续尺度研究。结果表明：(1)道路密度、开发密度、容积率均与建筑能耗呈正相关，但各指标对应的能耗时期、尺度范围有较大差异。(2)水面率、土地利用混合度是与建筑能耗相关的共性指标，但在不同地区的正负效应及尺度范围不同；(3)影响浙闽地区县域城镇最热月份能耗期能耗的关键形态因子为1000m-道路密度、800m-水面率、1600m-开放空间率；影响连江最冷月份能耗期能耗的关键形态因子为800m-水面率。(4)就控碳单元设置而言，长兴县可重点关注1000—1200m半径范围，连江县可重点关注800—1000m、1400m半径范围。(5)浙闽地区县域城镇特性指标为开放空间率，与最热月份能耗期建筑能呈负相关；长兴县特性指标为容积率、水岸密度，分别与全年、最冷...     

Identification of long-lived proteins in the mitochondria reveals increased stability of the electron transport chain

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Simple oligonucleotide-based multiplexing of single-cell chromatin accessibility

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Frequency-dependent conspecific attraction to food patches

In many ecological situations, resources are difficult to find but become more apparent to nearby searchers after one of their numbers discovers and begins to exploit them. If the discoverer cannot monopolize the resources, then others may benefit from joining the discoverer and sharing their discovery. Existing theories for this type of conspecific attraction have often used very simple rules for how the decision to join a discovered resource patch should be influenced by the number of individuals already exploiting that patch. We use a mechanistic, spatially explicit model to demonstrate that individuals should not necessarily simply join patches more often as the number of individuals exploiting the patch increases, because those patches are likely to be exhausted soon or joining them will intensify future local competition. Furthermore, we show that this decision should be sensitive to the nature of the resource patches, with individuals being more responsive to discoveries in general and more tolerant of larger numbers of existing exploiters on a patch when patches are resource-rich and challenging to locate alone. As such, we argue that this greater focus on underlying joining mechanisms suggests that conspecific attraction is a more sophisticated and flexible tactic than currently appreciated.     

Spatial relations and population structure of a dominant tree along a treeline ecotone in the Tropical Andes: interactions at gradient and plant-neighbourhood scales

Background: Studies in temperate mountains suggest that plant–plant interactions modulate tree establishment above the forest line. In tropical mountains worldwide this issue remains largely unexplored.

Aims: To analyse the population structure and local spatial relationships of a dominant tree at a species-rich tropical Andean forest line.

Methods: We determined changes in the population structure of Diplostephium venezuelense along an elevation gradient between continuous forest and open páramo and analysed plant community structure and superficial rock cover in the neighbourhood of saplings and adults at the upper forest line.

Results: Sapling and adult densities were highest in low-altitude páramos adjacent to the forest line and at the borders of small forest islands. Saplings showed local spatial aggregation, were positively associated with small boulders and low shrubs, and negatively associated with mosses and lichens. However, no spatial association was found between scattered adults in the páramo and saplings of other forest trees.

Conclusions: Complex species-specific local spatial interactions, suggesting both facilitative and antagonistic effects, seem to modulate the establishment of the dominant tree D. venezuelense at and above the upper forest line. Nevertheless, the establishment of other tree species above continuous forests does not appear to be facilitated by the canopy cover offered by the isolated D. venezuelense individuals established in open páramo environments.     

基于空间面板STIRPAT模型的水足迹影响因素分析——以山东省为例

随着中国水资源供需矛盾加剧，虚拟水成为地区水资源管理中不可或缺的一环，为提高地区水资源综合利用效率和探索水资源区域一体化管理提供了新思路。采用"自下而上"法核算了山东省17个城市农业、工业、生活、生态与灰水足迹，在分析2009-2018年水足迹时空分布规律基础上，综合运用探索性空间数据分析方法、面板数据STIRPAT模型和空间杜宾模型，揭示了水足迹的空间自相关特征，量化分析了人口数量、富裕程度、技术进步、城镇化和产业升级等影响因素对水足迹的本地影响效应与空间溢出效应。结果显示：①2009-2018年山东省水足迹总量均呈现波动上升的变化趋势；空间布局上呈现东部沿海和西部平原水足迹高，中部山地水足迹低的特点。②山东省水足迹具有正向的空间自相关性，相比地理位置相邻，水足迹的空间相关性受人口数量因素影响更大，表现出明显的"高高"聚集和"低低"聚集特征，但是受到经济因素的主要影响，区域间水足迹空间相关性随时间发展逐渐下降。③人口数量是山东省水足迹增长的重要来源，经济增长是推动各地区间水资源竞争关系的最重要因素。城镇化能够缓解本地水资源压力，技术进步和产业升级不仅能缓解本地水资源压力，而且通过空间溢出效应有效缓解临近地区水资源压力，是实施水资源区域一体化管理策略的重要着眼点。     

Dosimetric effect of tissue heterogeneity for 125I prostate implants

AimTo use Monte Carlo (MC) together with voxel phantoms to analyze the tissue heterogeneity effect in the dose distributions and equivalent uniform dose (EUD) for ¹²⁵I prostate implants.BackgroundDose distribution calculations in low dose-rate brachytherapy are based on the dose deposition around a single source in a water phantom. This formalism does not take into account tissue heterogeneities, interseed attenuation, or finite patient dimensions effects. Tissue composition is especially important due to the photoelectric effect.Materials and methodsThe computed tomographies (CT) of two patients with prostate cancer were used to create voxel phantoms for the MC simulations. An elemental composition and density were assigned to each structure. Densities of the prostate, vesicles, rectum and bladder were determined through the CT electronic densities of 100 patients. The same simulations were performed considering the same phantom as pure water. Results were compared via dose–volume histograms and EUD for the prostate and rectum.ResultsThe mean absorbed doses presented deviations of 3.3–4.0% for the prostate and of 2.3–4.9% for the rectum, when comparing calculations in water with calculations in the heterogeneous phantom. In the calculations in water, the prostate D₉₀ was overestimated by 2.8–3.9% and the rectum D_0.1cc resulted in dose differences of 6–8%. The EUD resulted in an overestimation of 3.5–3.7% for the prostate and of 7.7–8.3% for the rectum.ConclusionsThe deposited dose was consistently overestimated for the simulation in water. In order to increase the accuracy in the determination of dose distributions, especially around the rectum, the introduction of the model-based algorithms is recommended.     

Distribution and migration of Mississippi Kites in South America

Mississippi Kites (Ictinia mississippiensis) are trans‐equatorial, long‐distance migrants that breed in North America and overwinter in South America. Information about their migration routes and winter distribution in the Neotropics is mostly anecdotal. By compiling records of Mississippi Kites in South America from the literature and previously unpublished observations (1904–2010), we identified 96 locality records (a location where a flock or individual was recorded) and 146 independent records of flocks (observations of flocks irrespective of year, location, or time of year). Our locality records included 38 (39%) during southbound migration (1 September–30 November), 18 (19%) during northbound migration (15 February–30 April), 38 (39%) during austral summer (1 December–14 February), and two (3%) during austral winter (1 May–31 August). Most Mississippi Kites (84, 88%) were observed between the 11°S and 32°S latitudinal band in central South America. Of our independent records of flocks, 133 (92%) were observed between 11°S and 32°S, 12 (7%) between 11°N and 10°S, and a lone vagrant (1%) between 33°S and 43°S. Our data suggest that Mississippi Kites are common and widespread in the austral summer between 11°S and 32°S in central South America. On the basis of the number of locality records (N = 52, 54%) and number of flocks of Mississippi Kites observed between 22°S and 32°S (N = 61, 42%), the Chaco forest appears to be the main wintering grounds for the species. However, additional monitoring is needed to further test this hypothesis. A large portion of Chaco habitat is now under cultivation, and how this habitat transformation might influence the annual cycle of Mississippi Kites is unknown.