Circular Platform Research Articles

Design and analysis of the hydraulic driving system for the circular transfer platform of the CFETR divertor

Abstract In this study, a single-pump closed-loop hydraulic system with multiple actuators and load sensitivity is designed for a circular transfer platform, which remotely handles the divertor of the China Fusion Engineering Test Reactor by rotating the divertor module in the non-maintenance window to the designated position along the circular track. The proposed system controls the position and force of the pushing and locking cylinders. The designed closed-loop system synchronizes the movements of the internal and external cylinders. It also controls the displacement and force of the locking cylinder, ensuring the stability of the clamping force and the controllable position of the cylinder. Furthermore, the dynamic performance of the hydraulic control system is verified via the Adams–AMESim software co-simulation.

Inescapable exposure to the Barnes maze increases preference for alcohol over water in rats: Implications for depression and anxiety

Various sources of stress induce alcohol intake in rodents, including inescapable shocks, physical restraint, and reward loss. One hypothesis maintains that alcohol intake increases because its anxiolytic properties reduce negative emotion. A series of experiments explored this hypothesis using escapable vs. inescapable exposure to the well-lit circular platform of a Barnes maze in a master/yoked (M/Y) design, with pairs of rats matched in the amount of time on the lighted platform, but differing in terms of the presence vs. absence of an escape box. In Experiment 1 the M/Y design was validated as a means of producing rapid acquisition of escape behavior in master animals. In Experiment 2, immediate postsession access to a 2-h, 2-bottle preference test with 8 % alcohol and water resulted in a higher increase in preference for alcohol over water across sessions in yoked animals compared to master animals. Group differences were not observed when animals had access to water in both bottles. Higher preference for 8 % alcohol in yoked vs. master animals was also observed when the Barnes maze and preference test were separated by a 1-h interval (Experiment 3). However, voluntary alcohol consumption was similar in master and yoked animals when the order of exposure to the Barnes maze and fluid consumption was reversed (Experiment 4) or when the threat level was reduced by using a dim light over the Barnes maze (Experiment 5). Increased preference for alcohol after inescapable exposure to the Barnes maze is consistent with the hypothesis that alcohol alleviates negative mood and anxiety induced by an inescapable threat. This animal model is relevant to an understanding of the initial stages of co-morbidity between depression, anxiety, and alcohol use.

Plasmonic hotspot in toroidal metamaterial

Toroidal dipole resonance under a normal incident excitation can be realized by designing a metallic circular groove with a depth asymmetry. Due to its specific radial charge current configuration, charges gather together on the central circular platform and form a plasmonic hotspot, covering a large circular region with a diameter of 200 nm, where E-field magnitude attains 34-time enhancement than that of the incident light, providing more potentials for energy harvesting or nanoparticle trapping, manipulating of light–matter interaction, and optical data storage.

Пропозиції щодо реконструкції парку села Піківець Уманського району

Парк у с. Піківець Уманського району Черкаської області було закладено у 50-60-х роках ХХ ст. у центрі села, а саме біля сільського клубу. Насамперед потрібно провести санітарне рубання та обрізування дерев. Пропонуємо підсіяти мавританський газон, а в місці, де зростає пирій повзучий (Elytrigia repens L.), повністю замінити травостій на газон. Згідно з проектом розширюється стежкова мережа. Запропоновано створення доріжок з бетонної тротуарної плитки завширшки 0,75 та 1,5 м. Деякі стежки виконуватимуть транзитну роль, а деякі сполучатимуть окремі елементи парку. З малих архітектурних форм у парку встановлюємо альтанку для відпочинку. Також запропоновано збільшити кількість лавок, додавши дугоподібну лавку на круглому майданчику, у центрі якого розміщуватиметься клумба. Позаду кругової лавки, у північно-східній частині парку запроектовано створення декоративної групи з кущів. Асортимент рослин для цієї групи включає: Berberis thunbergii DC, Forsythia europaea Deg. et Bald., Pyracantha coccinea (L.) M. Roem, Syringa vulgaris L., Cotoneaster horizontalis Decne. Для клумб використовуємо цибулькові ранньоквітучі види, а також переважно тіньовитривалі багаторічники. Рекомендуємо створити мавританський газон, до складу якого входять: костриця червона (Festuca rubra L.), райграс пасовищний (Lolium perenne L.), тонконіг лучний (Poa pratensis L.), мак польовий (Papaver rhoeas L.), льон великоквітковий (Linum grandiflorum Desf.), ромашка лікарська (Matricaria recutita L.), низькорослі сорти космеї (Cosmos Cav.), чорнобривці мексиканські (Tagetes tenuifolia Сav.), гіпсофіла повзуча (Gypsophila muralis L.), гіпсофіла витончена (Gypsophila elegans M. Bieb.).

Poly(glycidyl ether)s recycling from industrial waste and feasibility study of reuse as electrolytes in sodium-based batteries

The need to recycle waste products, convert and reuse them for different high-value applications is a very up-to-date, utmost important topic. In this context, here we propose glycidol, a high-value product isolated from epichlorohydrin industry waste, as a starting material for the preparation of two poly(glycidol)s polymer matrices with a chemical structure mimicking that of poly(ethylene oxide), i.e. the most used polymer matrix for non-liquid battery electrolytes. The materials are characterized from the physico-chemical viewpoint, showing high thermal stability. They are then obtained in the form of ionic conducting polymer electrolytes encompassing different sodium salts and solvent mixtures. Ionic conductivity values exceeding 10−5 S cm−1 are measured in the “dry” truly solid state at 80 °C, while it approaches 6 × 10−5 S cm−1 at ambient temperature in the “wet” quasi-solid state. In addition, poly(glycidol)-based polymer matrices show reasonably wide electrochemical stability towards anodic oxidation. It envisages their possible use as separating electrolytes in secondary batteries, which is also demonstrated by preliminary charge/discharge cycling tests in lab-scale sodium cells. The present findings pave the way to a circular economy platform starting from industry wastes and ending with post-lithium storage systems.

Scheduling Concurrent Visual Feedback in Learning a Continuous Balance Task

This investigation held concurrent visual feedback frequency at 50% in the acquisition phase and manipulated three different feedback schedules while comparing those to a 0% feedback frequency. In an assessment of dynamic postural stability, young, healthy adults performed 20 acquisition trials and four retention trials 48-hr later on a circular platform that moved in the anterior/posterior and medial/lateral axes simultaneously. Three concurrent feedback schedules were manipulated: a fade schedule consisting of high relative frequency of concurrent feedback early in the acquisition phase which was systematically reduced throughout acquisition (e.g., 100%, 75%, 50%, 25%, 0%), a constant schedule consisting of a uniform scheduling of concurrent feedback on every other acquisition trial, and a reverse fade group consisting of a schedule exactly opposite to that of the fade group. A no concurrent feedback group was also utilized to determine if feedback was necessary to learn the balance task. Acquisition and retention results revealed the concurrent groups performed with significantly greater accuracy and stability than the no concurrent feedback group. There were no significant differences between the three concurrent feedback schedules. Results indicate that manipulating concurrent feedback scheduling did not produce similar results to those investigations manipulating knowledge of results scheduling.

A Study on the Pressure-Lowering Effect of the Multilayer Stent

The objective of the study was to investigate the hemodynamic changes of the blood flow in the aneurysm model after the multilayer stent placement using the fluid dynamic method, to analyze the effectiveness and properties of the multilayer stent in the treatment of aortic aneurysms. A water tank was filled with 5 L of experimental liquid after the circular flow pressure test platform with a glass aneurysm model, and a multilayer stent was built. Pressure at the middle part and the distal aneurysm neck part of the model was then measured. At each site, the pressure was measured 20 times at 1-min intervals, and the testing results were averaged for accuracy. Without the stent, mean pressure at the middle part and at the distal aneurysm neck part of the model was 11.19±0.23 Kpa and 13.31±0.28 Kpa, respectively. With the stent, the mean pressure decreased to 10.60±0.27 Kpa and 12.60±0.29 Kpa, and the average difference was 0.59±0.15 Kpa and 0.71±0.15 Kpa, respectively. After the placement of the multilayer stent, pressure inside the model at the middle part and distal neck part could both be diminished, yet the mean dropped pressure may be too small to be sufficient to cause significant impact on preventing the expansion of abdominal aortic aneurysm; therefore, the pressure-lowering effect of the multilayer stent for abdominal aortic aneurysm may not be ideal compared with the traditional covered stents.

Robust trajectory tracking control of omni-mobile robot with slipping of the wheels

In this paper we consider the problem of constructing a robust controller to track the trajectory of a mobile robot with three omni-wheels moving on a horizontal surface. A dynamic model of the robot has been constructed such that the center of mass of the circular platform is offset from its geometric center and the wheel slippage occurs during braking. The motion control of the wheeled robot is carried out by using three independent DC motors. The torques developed by the engines are linear with respect to voltage supplied to the engine and to angular velocity of the rotor. Basing on the Lyapunov function method we construct a bounded controller without velocity measurement that solves the robust trajectory tracking problem. This means that for all initial deviations the robot's trajectory falls into a given neighborhood of the tracked trajectory after some time and remains there forever. Theorem on an ultimate boundedness of a closed system is proved. The results of numerical simulation are presented confirming the effectiveness of the proposed controller.

Using an online platform for the improvement of industrial symbiosis and circular economy (in Western Macedonia, Greece)

<p>The part of industrial ecology known as industrial symbiosis engages traditionally separate industries in a collective approach to competitive advantage involving physical exchange of materials, energy, water and by-products (Dounavis et al. 2015, Dounavis et al. 2016, Ravindran and Jaiswal 2016, Kourmentza et al. 2018, Keskisaari and Kärki 2018, Ayadi et al. 2018). The keys to industrial symbiosis are collaboration and the synergistic possibilities offered by geographic proximity. Industrial symbiosis includes initiatives in which two or more industrial entities develop both beneficial relationships and the circular economy (Chowdhury et al. 2018). Since, the symbiosis encourages the sustainable development and promotes the economy growth (de Jesus et al. 2018). This paper presents an online industrial symbiosis and circular economy platform created by a LIFE project (still ongoing) which aims to demonstrate the usefulness of a digital on-line platform at European level for the cataloguing, use and exploitation of industrial waste produced in a local area in order to improve the overall performance of industrial processes and circular economy in a local level. All this will happen both through the increased use of waste within the area itself and by the less dependence on the disposal of waste to be disposed of, taking into account the reduction of used raw materials and the reduction of waste itself. The platform will be created through the European LIFE M3P Project (Material Match Making Platform for the promotion of the use of industrial waste in local networks) which is still on-going and ends at the end of September 2019.</p>

Product Service System-based Municipal Solid Waste circular management platform in Campania Region (Italy): a preliminary analysis

The huge amount of Municipal Solid Waste (MSW) generated in the world, as well as the adverse impacts on resources depletion, environmental contamination and human health are problems that need to be promptly, effectively and equitably addressed. Among the areas affected by management misconduct and illicit interests, the Campania region represents a paradigmatic case. A lack of detailed information about MSW flows, from collection and through treatment phases, prevents policy-makers and planners from finding appropriate and environmentally and economically sound solutions. As a partial approach to the solution, the authors of this paper outline the structure and functions of a Product Services System (PSS) based MSW management platform. In particular, data collection and elaboration, documentation of MSW flows and detection of environmental and human health impacts and waste prevention/reduction are essential elements of MSW of the system, within which the PSSs can be applied. Real-time sensors, big data analysis tools and online platforms are integrated, as basic tools, to implement the transition to equitable, sustainable circular economies. The solutions will be based upon multi-stakeholder inputs in decision-making to effectively address local needs to implement a re-designed, adaptive, dynamic, MSW management system. The new system must ensure safe and ecologically sound management of the resources in MSWs. As the new management system provides improvements in the environmental and human health and results in an expansion of jobs, it is anticipated that the system could also be useful in other parts of the world.

浑善达克沙地6种灌木生物量模拟

PDF HTML阅读 XML下载 导出引用 引用提醒 浑善达克沙地6种灌木生物量模拟 DOI: 10.5846/stxb201803290637 作者: 作者单位: 中国林业科学研究院荒漠化所,中国林业科学研究院 林业新技术研究所,内蒙古农业大学沙漠治理学院,中国林业科学研究院 荒漠化研究所,中国林业科学研究院荒漠化所,华北油田技术监督检验处计量中心站 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划项目（2016YFC0500801-03）；中国林业科学研究院基金（IDS2018JY-3，IDS2018JY-4）；国家自然科学基金项目（41401212） Biomass simulation of six shrub species in Otindag sandy land Author: Affiliation: Institute of Desertification Studies, Chinese Academy of Forestry,,,,Chinese Academy of Forestry, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:在干旱半干旱区，乔木比较稀疏或难以存活，灌木往往在植被群落中占有很大的优势地位，其生态功能及生态学意义尤其值得重视。浑善达克沙地疏林草地是沙地顶级植物群落，其中乔木稀疏分布，而灌木在沙甸以及沙陇背风坡呈密集分布。灌木在固定沙丘、改良土壤、提供栖息地等方面具有重要的生态意义，其生物量组成也在沙地植被群落中占有很大比重。已往的研究中，灌木相比乔木通常处于次要地位，对灌木的研究尚不充分，灌木生物量的模拟方法亦多采用乔木生物量的模拟方法。然而灌木形态结构与乔木有明显差异，专门针对灌木的生物量模拟方法研究尚不多见。以6种沙地灌木为样本，基于异速生长模型，对比了若干地表测量指标对灌木生物量的预测能力，其中设计了一种更贴近灌木实际形态的圆台体积作为新的预测指标。研究结果表明：（1）在单因素指标中，相比高度和地径，冠幅与灌木生物量的相关性更强。（2）相比单因素指标，复合指标与灌木生物量之间的相关性更强。其中冠幅相关的复合指标更优于地径相关的复合指标。这预示着冠幅以及冠幅相关的复合指标对灌木生物量具有较好的预测能力。（3）圆台体积能进一步提高对灌木生物量的预测能力。相关分析和拟合评价结果显示，圆台体积与灌木生物量的相关性更强，拟合误差较小，并且对于不同的灌木种类，其相关性和拟合精度表现出较高的稳定性。这意味着圆台体积对于不同的灌木种类，均具有较好的生物量预测效果。因此建议，在灌木属性测量较为充分的情况下，圆台体积是更为理想的预测指标，而在测量不充分情况下，冠幅及其相关复合指标更适宜进行灌木生物量预测。研究结果最终建立了6种沙地灌木的圆台体积-生物量的异速生长模拟方程，为进一步研究沙地灌木的碳储量以及灌木在半干旱植物群落中的生态意义提供科学基础。 Abstract:In arid and semi-arid regions, trees are sparse or have difficulty surviving, and shrubs often occupy a dominant position in vegetation communities. The ecological functions and ecological value of shrubs are particularly worthy of attention in these regions. The sparse-elm grassland in Otindag Sandy Land is the climatic climax community; the trees are sparsely distributed, while the shrubs are densely distributed between the dunes or on the leeward slopes of the dunes. Shrubs have significant ecological functions in fixing sand dunes, improving soils, providing habitats, and increasing vegetation biodiversity. Shrub biomass accounts for a large proportion of the sandy land vegetation community. According to previous studies, shrubs are usually less important than trees, but the research on shrubs is not yet sufficient. The present shrub biomass simulation method is mostly adapted from the methods used for trees. However, the morphological characteristics of shrubs are obviously different from those of trees. A biomass prediction model specific for shrubs urgently needs to be developed. In this study, six dominant shrub species were investigated. Based on an allometric model, seven shrub measurements were used as predictors and compared to assess their abilities to predict shrub biomass. Among the seven measurements, a circular platform volume model, which has a structure close to the actual shape of a shrub, was designed as a new predictor. In this study, correlation coefficients and three model-fitting accuracy evaluation indices[including determination of the R2 coefficient, significance index p-values, and standard error of the estimate (SEE)] were used to assess the prediction ability of the seven measurements. The results showed that:(1) Among the single measurements, the correlation coefficient between the crown diameter and biomass was highest, compared to those between height or ground diameter and biomass. (2) The correlation between the composite indices and shrub biomass was much stronger than that between the single measurements and biomass. In addition, the crown-related composite indices had stronger correlations with biomass than the ground diameter-related composite index did. This indicates that the crown diameter or crown-related composite indices may be better in predicting shrub biomass. (3) The circular platform volume model further improved the ability to predict shrub biomass. The results of correlation analysis and fitting analysis showed that the correlation between the circular platform volume and biomass was stronger and the fitting error was smaller compared with other prediction indicators. The correlation and fitting accuracy between circular platform volume and biomass were similar across different shrub species. This means that the circular platform volume model has better and more-stable prediction ability than other models for many shrub species, which implies that it is also more scalable. Therefore, we suggest that the circular platform volume is an ideal predictor when shrubs are adequately measured in the field. Otherwise, if the shrubs are not sufficiently measured, the crown diameter and crown-related composite indices are more suitable for the prediction of shrub biomass. In sum, this study established a biomass prediction model based on the circular platform volume of the six sandy shrub species, which provides a scientific basis for further study of the shrub carbon sink in sandy land and the ecological significance of shrubs in semi-arid and arid regions. 参考文献 相似文献 引证文献

Improvement of Calculation of Stresses in the Earth Bed and Layers of Road Clothes from Granulated Materials. Part 1. Analysis of Decisions and a New Method

The bases of road clothes made of discrete materials have become widespread in the practice of building roads throughout the world. Experimental studies of various loads have shown that an adequate calculation of stresses by formulas in the mechanics of a continuous medium is practically impossible. The article presents a method for modifying stress calculation models, the application of which allows supplementing the solutions of granular medium mechanics and engineering methods with dependencies for calculating the minimum main stress σ3. Following this method, some solutions have been modified, and modified models are given. These models make it possible to calculate the main stresses in a layer of finite thickness in the section on the axis of symmetry of the load distributed along the circular platform. In accordance with this method, in the section along the axis of symmetry of the load at the point z=0 compression pressure occurs, that is ε2=ε3=0. Within the limits of depth change 0<z<∞ the soil operates under conditions of triaxial compression, experiencing lateral expansion strains ε2=ε3<0. At the point z=∞ the ground undergoes uniaxial compression σ2=σ3=0 and ε2=ε3=−μ·ε1.

Raw data videos offer a glimpse into laboratory research

In one video, a pair of detached butterfly wings slowly change colors from pale yellow to dark spots with splashes of orange. In another, a mouse explores a raised circular platform, peering at a checkerboard pattern on the floor below. A third clip shows a worm undulating in a funnel-shaped enclosure, bending tiny “pillars” with its body. An example of raw laboratory footage with aesthetic appeal, this image was taken from a time-lapse sequence of squid development documented by developmental biologist Nipam Patel and his students. It won runner-up for the Scientific Merit Award at ISF’s New York film festival last year. Image courtesy of Nipam Patel (University of California, Berkeley, CA). These videos are part of a collection of laboratory footage gathered by filmmaker Alexis Gambis and colleagues. Gambis, executive director of the nonprofit Imagine Science Films (ISF) and founder of the online science film platform Labocine , both in Brooklyn, NY, has long been fascinated by the visual appeal of raw data clips. His organizations have showcased videos ranging from microscopic observations to computer simulations posted online and shown at science film festivals and exhibits. In July, Labocine , which first started in 2016 as a subscription-based video magazine and online database of science cinema, launched a collection called “Scenes” on its website to highlight raw laboratory footage. Gambis, a former geneticist, says the videos offer an intimate glimpse into a world that is often obscured from the general public. “They get a palpable view of what’s happening in research today,” he says. And the raw footage is a departure from traditional science documentaries, which are heavily edited and typically use voice-over to describe scenes. “It’s oftentimes so chewed-up and explained to you,” Gambis says. The laboratory videos he and his team gather come with minimal information and …

An Older Adult Study of Concurrent Visual Feedback in Learning Continuous Balance.

This investigation manipulated concurrent visual feedback for older adults learning to perform a continuous balance task. We randomly assigned 21 older adults to one of three knowledge of results (KR) groups with varying concurrent but always 100% terminal feedback percentages during acquisition: 100% Concurrent and Terminal (100% C&T), 50% Concurrent and 100% Terminal (50% C & 100% T), and 0% Concurrent and 100% Terminal (0% C & 100% T). The continuous balance task involved learning to maintain balance on a circular platform that moved simultaneously on both anterior/posterior and medial/lateral axes. We tested participants before acquisition phase learning and two days afterwards (retention test). At retention testing, participants in the 50% C & 100% T and those in the 0% C & 100% T conditions demonstrated significantly greater accuracy and stability than did participants in the 100% C&T condition. These findings extend previous research with young adults in supporting the guidance theory that too frequent a provision of concurrent knowledge of results negatively affects learning.

THE BARNES MAZE TEST: A DRY LAND BEHAVIORAL TEST TO ANALYZE ALZHEIMER’S DISEASE MOUSE MODELS FOR SPATIAL LEARNING DEFICITS

Alzheimer's disease (AD) is a progressive neurodegenerative disease that manifests as memory loss, cognitive dysfunction and dementia. Spatial learning and memory of AD rodent models is often assessed via navigational cues in mazes, most popular are the Morris water maze and the dry-land Barnes maze. Improved performance over sessions or trials is thought to reflect learning and memory. The Barnes maze is considered less stressful compared to water mazes and also useful for rodent models with minor motor deficits. The Barnes maze is a circular platform top with several holes equally spaced around the perimeter edge. Symptomatic animals of two transgenic AD mouse models as well as mice with a scopolamine-induced learning challenge were analyzed in the Barnes maze test using a hippocampal learning protocol. Scopolamine is a competitive antagonist of the muscarinic acetylcholine receptor (mAChR). Systemic application of scopolamine is known to disrupt learning. Barnes maze results were analyzed for escape latency, speed, distance traversed, number of target entries, and the abidance in the target quadrant during the probe trial. Data of different models were compared. Our data show that the dry-land behavioral test apparatus of the Barnes maze is a valuable tool to analyze learning and memory deficits of different rodent AD models. This method might be an effective alternative to the Morris water maze while causing less stress to the animals.

Recurrent Hypoglycemia Exacerbates Cerebral Ischemic Damage in Diabetic Rats via Enhanced Post-Ischemic Mitochondrial Dysfunction.

Diabetes significantly increases the risk of stroke and post-stroke mortality. Recurrent hypoglycemia (RH) is common among diabetes patients owing to glucose-lowering therapies. Earlier, we showed that RH in a rat model of insulin-dependent diabetes exacerbates cerebral ischemic damage. Impaired mitochondrial function has been implicated as a central player in the development of cerebral ischemic damage. Hypoglycemia is also known to affect mitochondrial functioning. The present study tested the hypothesis that prior exposure of insulin-treated diabetic (ITD) rats to RH exacerbates brain damage via enhanced post-ischemic mitochondrial dysfunction. In a rat model of streptozotocin-induced diabetes, we evaluated post-ischemic mitochondrial function in RH-exposed ITD rats. Rats were exposed to five episodes of moderate hypoglycemia prior to the induction of cerebral ischemia. We also evaluated the impact of RH, both alone and in combination with cerebral ischemia, on cognitive function using the Barnes circular platform maze test. We observed that RH exposure to ITD rats leads to increased cerebral ischemic damage and decreased mitochondrial complex I activity. Exposure of ITD rats to RH impaired spatial learning and memory. Our results demonstrate that RH exposure to ITD rats potentially increases post-ischemic damage via enhanced post-ischemic mitochondrial dysfunction.

Scattering of periodic surface waves by pile-group supported platform

A semi-analytical approach is proposed to solve the scattering of free surface waves around a platform supported by a pile array. Assuming periodic lattice configuration and strong contrast between cylinder spacing and typical wavelength, the multi-scale perturbation theory of homogenization is employed to derive the effective equations governing the macro-scale wave dynamics and the boundary-value problem of micro-scale flows within a unit cell. The constitutive coefficient in the macro-scale effective equations are computed from the solution of the micro-scale boundary-value problem, which is driven by the macro-scale pressure gradient. Flow separation is treated by the eddy viscosity model where the bulk eddy viscosity is determined by balancing the time-averaged rate of dissipation and the rate of work done by wave forces on the cylinders integrated over the entire platform region. The proposed semi-analytical approach is validated by comparisons with laboratory experiments for a pile-group supported platform in a wave flume. In addition field-scale wave scattering by a pile-group supported circular platform is investigated. For long waves, the maximum vertical force exerted on pile-group supported platform may reach 1.2 times of the value without piles. The maximum increase of the torque in transverse direction occurs for intermediate waves, which may reach 40% for the parameters discussed.

Effects of acute administration of donepezil or memantine on sleep-deprivation-induced spatial memory deficit in young and aged non-human primate grey mouse lemurs (Microcebus murinus).

The development of novel therapeutics to prevent cognitive decline of Alzheimer's disease (AD) is facing paramount difficulties since the translational efficacy of rodent models did not resulted in better clinical results. Currently approved treatments, including the acetylcholinesterase inhibitor donepezil (DON) and the N-methyl-D-aspartate antagonist memantine (MEM) provide marginal therapeutic benefits to AD patients. There is an urgent need to develop a predictive animal model that is phylogenetically proximal to humans to achieve better translation. The non-human primate grey mouse lemur (Microcebus murinus) is increasingly used in aging research, but there is no published results related to the impact of known pharmacological treatments on age-related cognitive impairment observed in this primate. In the present study we investigated the effects of DON and MEM on sleep-deprivation (SD)—induced memory impairment in young and aged male mouse lemurs. In particular, spatial memory impairment was evaluated using a circular platform task after 8 h of total SD. Acute single doses of DON or MEM (0.1 and 1mg/kg) or vehicle were administered intraperitoneally 3 h before the cognitive task during the SD procedure. Results indicated that both doses of DON were able to prevent the SD-induced deficits in retrieval of spatial memory as compared to vehicle-treated animals, both in young and aged animals Likewise, MEM show a similar profile at 1 mg/kg but not at 0.1mg/kg. Taken together, these results indicate that two widely used drugs for mitigating cognitive deficits in AD were partially effective in sleep deprived mouse lemurs, which further support the translational potential of this animal model. Our findings demonstrate the utility of this primate model for further testing cognitive enhancing drugs in development for AD or other neuropsychiatric conditions.

Laminar Organization of Encoding and Memory Reactivation in the Parietal Cortex

Egocentric neural coding has been observed in parietal cortex (PC), but its topographical and laminar organization is not well characterized. We used multi-site recording to look for evidence of local clustering and laminar consistency of linear and angular velocity encoding in multi-neuronal spiking activity (MUA) and in the high-frequency (300-900Hz) component of the local field potential (HF-LFP), believed to reflect local spiking activity. Rats were trained to run many trials on a large circular platform, either to LED-cued goal locations or as a spatial sequence from memory. Tuning to specific self-motion states was observed and exhibited distinct cortical depth-invariant coding properties. These patterns of collective local and laminar activation during behavior were reactivated in compressed form during post-experience sleep and temporallycoupled to cortical delta waves and hippocampal sharp-wave ripples. Thus, PC neuron motion encoding is consistent across cortical laminae, andthis consistency is maintained during memory reactivation.

Multi-parametric stability investigation for thin spherical membranes with contacts

The instability behavior for a thin truncated spherical membrane completely filled with fluid or containing both gas and fluid, fixed on a circular platform and in contact with two vertical planes was investigated. Different penalty functions for contacts, and symmetry aspects of the discretized model were studied, and gave effects on instability behavior. Stability conclusions for the multi-parametric problems were made using generalized eigenvalue analyses, showing limit points, bifurcation points and turning point. Contact conditions were shown to introduce bifurcations and secondary paths, dependent on the contact implementations and discretizations. Their effects on stability behaviors in connection with various controlling equations are discussed.