Systems genetic analysis of hippocampal neuroanatomy and spatial learning in mice

Variation in hippocampal neuroanatomy correlates well with spatial learning ability in mice. Here, we have studied both hippocampal neuroanatomy and behavior in 53 isogenic BXD recombinant strains derived from C57BL/6J and DBA/2J parents. A combination of experimental, neuroinformatic and systems genetics methods was used to test the genetic bases of variation and covariation among traits. Data were collected on seven hippocampal subregions in CA3 and CA4 after testing spatial memory in an eight‐arm radial maze task. Quantitative trait loci were identified for hippocampal structure, including the areas of the intra‐ and infrapyramidal mossy fibers (IIPMFs), stratum radiatum and stratum pyramidale, and for a spatial learning parameter, error rate. We identified multiple loci and gene variants linked to either structural differences or behavior. Gpc4 and Tenm2 are strong candidate genes that may modulate IIPMF areas. Analysis of gene expression networks and trait correlations highlight several processes influencing morphometrical variation and spatial learning.     

Identifying key factors,actors and relevant scales in landscape and conservation planning,management and decision making: Promoting effective citizen involvement

The paper analyses the current limitations of the constraints of decision and action processes in land-use, resource management and conservation policies and approaches, identifying their main factors, proposing alternative strategies to solve the present gaps and limitations. It identifies the need for a new paradigmatic approach based on innovative forms of involvement, commitment and individual and community rewarding systems. This approach is developed based on the characterization of the main drivers of land-use, resource management and conservation policies, namely α-perceptions (immediate and primary satisfaction) and k-perceptions (more mediate and complex consideration of satisfaction, implying long-term perceptions and collective benefits beyond the individual interests). It also analyses the effects of the introduction of new forms of income and incentives (such as trade-offs and payments for environmental services) or management approaches such as Ecological-Based Management or the use of Nature-Based Solutions. The main axioms and instruments necessary to build such a new paradigmatic approach (namely trade-offs, accountability and contractualization) are described. On this basis, it is possible to present a concept for an innovative institutional and social culture and a governance system aimed at an effective land-use, resource management and conservation policies. This governance concept is described and its sustaining individual, social and institutional drivers enunciated.     

Equivalence of branched and unbranched Michaelian pathways concerning periodic signal transmission

Sinusoidal oscillation transmission through branched metabolic pathways is studied. Two systems are analyzed, which are composed of two convergent reaction branches and differ in the length of one of them. Linear kinetics is assumed first. Michaelis-Menten enzymes are then considered by using previous results that suggest their behavior with respect to propagation of oscillations is close to linearity around the mean input flux. As a result, there exist ways to modulate the activity of the enzymes so that propagation is equivalent for branched and specific unbranched pathways. Cells may have taken advantage of such a possibility in cases where oscillations have a biological role.     

寄主植物物理性状及营养物质对地红蝽寄主选择性的影响

【目的】地红蝽Pyrrhocoris tibialis是一种重要的农业植食性害虫,寄主范围广泛。本研究测定地红蝽对不同植物的取食偏好及分析寄主植物物理性状和营养物质在地红蝽成虫寄主选择行为中的作用,以期从寄主理化性状的角度来探讨地红蝽寄主选择行为机制,为指导作物抗虫育种提供依据。【方法】通过自由选择方法研究地红蝽成虫对5种寄主植物(谷子Setaria italica、高粱Sorghum bicolor、绿豆Vigna radiata、大豆Glycine max和玉米Zea mays)叶片的取食选择性;使用Y型嗅觉仪进一步检测地红蝽对5种植物叶片气味的趋性反应;测定分析5种植物叶片物理性状及主要营养物质含量与地红蝽取食选择性的相关性。【结果】地红蝽成虫对5种寄主植物叶片的取食选择率存在显著性差异,依次为谷子＞高粱＞绿豆＝大豆＞玉米,与对这5种寄主植物叶片气味的趋性反应百分率结果一致。相关性分析表明,地红蝽成虫的取食选择性与叶片长宽比、含水量和背面茸毛密度呈显著正相关,相关系数分别为0.881, 0.884和0.906,而与地红蝽成虫取食前后寄主植物叶片可溶性糖含量变化和总蛋白质含量变化呈显著负相关,相关系数分别为-0.915和-0.951。通径分析表明,寄主植物叶片背面茸毛密度和总蛋白质含量变化是地红蝽寄主选择性的重要决定因素。【结论】地红蝽成虫对不同寄主植物存在取食选择和趋向性差异,地红蝽成虫取食选择与寄主植物叶片长宽比、背面茸毛密度、含水量以及可溶性糖和总蛋白质含量变化有关。     

猴头菇对小鼠抗疲劳作用的实验研究

分别以猴头菇干粉（猴头菇Ⅰ组）和猴头菇浸出液（猴头菇Ⅱ组）饲喂小鼠,观察猴头菇对小鼠血清乳酸脱氢酶（ＬＤＨ）活力、血乳酸、血清尿素氮（ＢＵＮ）、肝糖原、肌糖原含量及运动耐力的影响。结果表明：实验６０ｄ后,猴头菇Ⅰ、Ⅱ组ＬＤＨ活力、肝糖原及肌糖原含量明显高于对照组（Ｐ＜０．０５或Ｐ＜０．０１）;运动后血乳酸的水平和ＢＵＮ的增量明显低于对照组（Ｐ＜０．０５或Ｐ＜０．０１）;运动后血乳酸消除速率显著高于对照组（Ｐ＜０．０５）;在运动耐力测定时在水中淹死的时间比对照组长得多（Ｐ＜０．０５）。提示：猴头菇具有明显的增强运动能力和解除疲劳的作用。     

Intact Histological Characterization of Brain-implanted Microdevices and Surrounding Tissue

Research into the design and utilization of brain-implanted microdevices, such as microelectrode arrays, aims to produce clinically relevant devices that interface chronically with surrounding brain tissue. Tissue surrounding these implants is thought to react to the presence of the devices over time, which includes the formation of an insulating "glial scar" around the devices. However, histological analysis of these tissue changes is typically performed after explanting the device, in a process that can disrupt the morphology of the tissue of interest.Here we demonstrate a protocol in which cortical-implanted devices are collected intact in surrounding rodent brain tissue. We describe how, once perfused with fixative, brains are removed and sliced in such a way as to avoid explanting devices. We outline fluorescent antibody labeling and optical clearing methods useful for producing an informative, yet thick tissue section. Finally, we demonstrate the mounting and imaging of these tissue sections in order to investigate the biological interface around brain-implanted devices.     

Characterization of Food Physical Properties by the Mastication Parameters Measured by Electromyography of the Jaw-Closing Muscles and Mandibular Kinematics in Young Adults

The relationship between the physical properties of solid food and the masticatory parameters is clarified. Eight solid foods of varying physical properties were chosen. Electromyography of the jaw-closing muscles and mandibular kinematics in eleven young subjects were recorded. The masticatory parameters were derived from the recorded data for the entire mastication process, for the first bite, and in the early, middle, and late stages of mastication. After calculating values relative to the mean value for each subject, nine parameters representing each group were chosen through a cluster analysis. Three principal components were extracted, each of them related to the masticatory time and cycle, minimum jaw opening at the early stage of mastication, and masticatory force. The principal component scores for each food were different, except for one combination in which the physical properties under large and extra-large deformations were similar, despite different breaking properties or small deformation properties. The masticatory parameters did not correlate with the physical properties of food measured for small deformation.     

Likelihood of changes in forest species suitability,distribution, and diversity under future climate: The case of Southern Europe

Forest conservation strategies and plans can be unsuccessful if the new habitat conditions determined by climate change are not considered. Our work aims at investigating the likelihood of future suitability, distribution and diversity for some common European forest species under the projected changes in climate, focusing on Southern Europe. We combine an Ensemble Platform for Species Distribution Models (SDMs) to five Global Circulation Models (GCMs) driven by two Representative Concentration Pathways (RCPs), to produce maps of future climate‐driven habitat suitability for ten categories of forest species and two time horizons. For each forest category and time horizon, ten maps of future distribution (5 GCMs by 2 RCPs) are thus combined in a single suitability map supplied with information about the “likelihood” adopting the IPCC terminology based on consensus among projections. Then, the statistical significance of spatially aggregated changes in forest composition at local and regional level is analyzed. Finally, we discuss the importance, among SDMs, that environmental predictors seem to have in influencing forest distribution. Future impacts of climate change appear to be diversified across forest categories. A strong change in forest regional distribution and local diversity is projected to take place, as some forest categories will find more suitable conditions in previously unsuitable locations, while for other categories the same new conditions will become less suited. A decrease in species diversity is projected in most of the area, with Alpine region showing the potentiality to become a refuge for species migration.