Understanding the effect of landscape fragmentation and vegetation productivity on elephant habitat utilization in Amboseli ecosystem,Kenya

Understanding factors affecting the distribution of the African elephant is important for its conservation in increasingly human‐dominated savannah landscapes. However, understanding how landscape fragmentation and vegetation productivity affect elephant habitat utilization remains poorly understood. In this study, we tested whether landscape fragmentation and vegetation productivity explain elephant habitat utilization in the Amboseli ecosystem in Kenya. We used GPS (Global Positioning System) telemetry data from five elephants to quantify elephant habitat utilization. Habitat utilization was determined by calculating the time elephants spent within a unit area. We then used generalized additive models (GAMs) to model the relationship between time density and landscape fragmentation, as well as vegetation productivity. Results show that landscape fragmentation and vegetation productivity significantly (P < 0.05) explain elephant habitat utilization. A significant (P < 0.05) unimodal relationship between vegetation productivity and habitat utilization was observed. Results suggest that elephants spend much of their time in less fragmented landscapes of intermediate productivity.     

七氟醚联合骶管阻滞麻醉对小儿疝气手术的麻醉效果分析

目的:观察七氟醚联合骶管阻滞麻醉对小儿疝气手术的麻醉效果。方法:选取80例行腹股沟疝气手术患儿,按随机数字表法分为两组,对照组(39例)静脉注射氯胺酮,观察组(41例)先吸入8%七氟醚,然后进行骶管阻滞麻醉,通过观察并记录两组患儿生命体征、麻醉诱导时间、苏醒时间、手术麻醉时间、苏醒期躁动评分(Pediatric anesthesia emergence delirium,PAED)和麻醉诱导期合作量表(Induction Compliance Checklist,ICC)及麻醉期间不良反应情况,评价七氟醚联合骶管阻滞麻醉对小儿疝气手术的麻醉效果。结果:两组切皮后T1、T2时心率(HR)、平均动脉压(MAP)水平均高于T0时的值(P0.05),两组切皮后T1、T2时组间HR、MAP水平相比,无统计学差异(P0.05)。两组切皮后T3时HR、MAP水平基本恢复到T0时的水平。两组切皮前后4个时间点的血氧饱和度(Sp O2)相比,无统计学差异(P0.05)。观察组患儿麻醉诱导时间,苏醒时间均明显短于对照组患儿(P0.05),两组术中麻醉持续时间相比,无统计学差异(P0.05),均能达到期望麻醉时间,观察组患儿PAED评分和ICC评分均低于对照组患儿(P0.05),不良反应组间比较无统计学差异(P0.05)。结论:七氟醚联合骶管阻滞麻醉对小儿疝气手术具有良好的麻醉效果,麻醉诱导快,苏醒快,小儿配合度高,术后躁动少,值得临床推广使用。     

Response to rearing in laboratory of the xylophagous grape pest,Xylotrechus arvicola (Coleoptera: Cerambycidae)

Xylotrechus arvicola (Olivier) (Coleoptera: Cerambycidae) is an important pest in vineyards (Vitis vinifera) in the main Iberian wine‐producing regions. Larvae were reared with Semi‐Synthetic Iglesias (SSI) diet over 27 months and two generations in the laboratory. Larval mortality was highest during the first (49.49 %) and second (9.38 %) month of rearing, increasing to 50.52 % during the first month if F2 reared larvae were obtained from an F1 adult female obtained in laboratory. The diet had sufficient nutrients to enable the pest to complete its life cycle within nine months, with F1 larval viability ranging from 23.49 % to 27.97 % and F2 larval viability reduced to 2.07 %. However, the diet did not allow for the completion of additional life cycles and generations (F3, F4,…). Larval mortality increased as the months of rearing (66.13 %, 69.51 % and 89.50 %) and generations (59.10 % and 76.93 % in F1 and F2, respectively) progressed in the laboratory. The larva–adult period of females obtained in the laboratory was longer than for males. In the laboratory, the life cycle was shortened in relation to the life cycle in the field because larvae did not require a cold period to break diapause and start pupation. This indicates that X. arvicola has the potential to complete its life cycle inside grape wood in vineyards of wine‐producing regions with warmer winters.     

Evolution of Hot Polaron States with a Nanosecond Lifetime in a Manganite Perovskite

Understanding and controlling the relaxation process of optically excited charge carriers in solids with strong correlations is of great interest in the quest for new strategies to exploit solar energy. Usually, optically excited electrons in a solid thermalize rapidly on a femtosecond to picosecond timescale due to interactions with other electrons and phonons. New mechanisms to slow down thermalization will thus be of great significance for efficient light energy conversion, e.g., in photovoltaic devices. Ultrafast optical pump–probe experiments in the manganite Pr_0.65Ca_0.35MnO_3, a photovoltaic, thermoelectric, and electrocatalytic material with strong polaronic correlations, reveal an ultraslow recombination dynamics on a nanosecond‐time scale. The nature of long living excitations is further elucidated by photovoltaic measurements, showing the presence of photodiffusion of excited electron–hole polaron pairs. Theoretical considerations suggest that the excited charge carriers are trapped in a hot polaron state. Escape from this state is possible via a slow dipole‐forbidden recombination process or via rare thermal fluctuations toward a conical intersection followed by a radiation‐less decay. The strong correlation between the excited polaron and the octahedral dynamics of its environment appears to be substantial for stabilizing the hot polaron.     

Real‐time cell analysis and heat shock protein gene expression in the TcA Tribolium castaneum cell line in response to environmental stress conditions

The rust red flour beetle, Tribolium castaneum (Herbst, 1797) (Coleoptera: Tenebrionidae), is a pest of stored grain and one of the most studied insect model species. Some of the previous studies involved heat response studies in terms of survival and heat shock protein expression, which are regulated to protect other proteins against environmental stress conditions. In the present study, we characterize the impedance profile with the xCELLigence Real‐Time Cell Analyzer and study the effect of increased temperature in cell growth and viability in the cell line BCIRL‐TcA‐CLG1 (TcA) of T. castaneum. This novel system measures cells behavior in real time and is applied for the first time to insect cells. Additionally, cells are exposed to heat shock, increased salinity, acidic pH and UV‐A light with the aim of measuring the expression levels of Hsp27, Hsp68a, and Hsp83 genes. Results show a high thermotolerance of TcA in terms of cell growth and viability. This result is likely related to gene expression results in which a significant up‐regulation of all studied Hsp genes is observed after 1 h of exposure to 40 °C and UV light. All 3 genes show similar expression patterns, but Hsp27 seems to be the most affected. The results of this study validate the RTCA method and reveal the utility of insect cell lines, real‐time analysis and gene expression studies to better understand the physiological response of insect cells, with potential applications in different fields of biology such as conservation biology and pest management.