scholarly journals Fabrication of an inexpensive, implantable cooling device for reversible brain deactivation in animals ranging from rodents to primates

2012 ◽  
Vol 107 (12) ◽  
pp. 3543-3558 ◽  
Author(s):  
Dylan F. Cooke ◽  
Adam B. Goldring ◽  
Itsukyo Yamayoshi ◽  
Phillippos Tsourkas ◽  
Gregg H. Recanzone ◽  
...  
Keyword(s):  
Cortical Plasticity ◽  
Temperature Drop ◽  
Neural Responses ◽  
Cooling Device ◽  
Behavioral Studies ◽  
Chip Fabrication ◽  
Cortical Temperature ◽  
And Performance ◽  
Neural Signaling

We have developed a compact and lightweight microfluidic cooling device to reversibly deactivate one or more areas of the neocortex to examine its functional macrocircuitry as well as behavioral and cortical plasticity. The device, which we term the “cooling chip,” consists of thin silicone tubing (through which chilled ethanol is circulated) embedded in mechanically compliant polydimethylsiloxane (PDMS). PDMS is tailored to compact device dimensions (as small as 21 mm3) that precisely accommodate the geometry of the targeted cortical area. The biocompatible design makes it suitable for both acute preparations and chronic implantation for long-term behavioral studies. The cooling chip accommodates an in-cortex microthermocouple measuring local cortical temperature. A microelectrode may be used to record simultaneous neural responses at the same location. Cortex temperature is controlled by computer regulation of the coolant flow, which can achieve a localized cortical temperature drop from 37 to 20°C in less than 3 min and maintain target temperature to within ±0.3°C indefinitely. Here we describe cooling chip fabrication and performance in mediating cessation of neural signaling in acute preparations of rodents, ferrets, and primates.

Design and planning of the balanced scorecard: A case study

2007 ◽  
Vol 26 (3) ◽  
pp. 217-227
Author(s):  
Ming-Hon Hwang ◽  
Hsin Rau
Keyword(s):  
Performance Evaluation ◽  
Balanced Scorecard ◽  
Process Management ◽  
Planning Process ◽  
Company Performance ◽  
Correct Process ◽  
The Balanced Scorecard ◽  
Strategy Planning ◽  
And Performance

In the industrial economy, evaluating company performance based on financial results was good enough. However, in the current globalized and highly competitive environment, maintaining long term competitiveness requires companies to engage in overall strategic planning and performance evaluation. The balanced scorecard is a tool or method for balancing an organization's performance and can react to situations where a company's direction becomes disoriented. This approach assists in strategy planning, process management, and performance evaluation from four perspectives, including financial, customer, internal process, and learning and growth. Good strategy planning provides companies with a correct management direction, correct process management ensures the efficient execution of plans, and correct performance evaluation illustrates the execution results. This study mainly focuses on how a large rubber company in Taiwan utilizes the balanced scorecard in its organization. As the technical perspective is important in the rubber keypad industry, besides the four above perspectives, this company has added the technical perspective. By introducing this company and its progress in implementing the balanced scorecard, this study hopes to provide other companies, especially rubber companies, with a planning direction and reference for the future implementation of the balanced scorecard.

Optimal adaptive inspection and maintenance for redundant systems

2021 ◽  
pp. 1748006X2110201
Author(s):  
Chaochao Lin ◽  
Matteo Pozzi
Keyword(s):  
Engineering Systems ◽  
Discounted Cost ◽  
Markov Decision ◽  
Inspection And Maintenance ◽  
And Performance ◽  
Partially Observable ◽  
Series Systems ◽  
Selection Of ◽  
Redundant Systems

Optimal exploration of engineering systems can be guided by the principle of Value of Information (VoI), which accounts for the topological important of components, their reliability and the management costs. For series systems, in most cases higher inspection priority should be given to unreliable components. For redundant systems such as parallel systems, analysis of one-shot decision problems shows that higher inspection priority should be given to more reliable components. This paper investigates the optimal exploration of redundant systems in long-term decision making with sequential inspection and repairing. When the expected, cumulated, discounted cost is considered, it may become more efficient to give higher inspection priority to less reliable components, in order to preserve system redundancy. To investigate this problem, we develop a Partially Observable Markov Decision Process (POMDP) framework for sequential inspection and maintenance of redundant systems, where the VoI analysis is embedded in the optimal selection of exploratory actions. We investigate the use of alternative approximate POMDP solvers for parallel and more general systems, compare their computation complexities and performance, and show how the inspection priorities depend on the economic discount factor, the degradation rate, the inspection precision, and the repair cost.

scholarly journals A Compact Muon Tracker for Dynamic Tomography of Density Based on a Thin Time Projection Chamber with Micromegas Readout

Particles ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 333-342
Author(s):  
Ignacio Lázaro Roche
Keyword(s):  
Time Projection Chamber ◽  
Wide Field ◽  
Track Reconstruction ◽  
Long Term Stability ◽  
Societal Issues ◽  
Primary Signal ◽  
And Performance ◽  
Time Projection

Tomography based on cosmic muon absorption is a rising technique because of its versatility and its consolidation as a geophysics tool over the past decade. It allows us to address major societal issues such as long-term stability of natural and man-made large infrastructures or sustainable underwater management. Traditionally, muon trackers consist of hodoscopes or multilayer detectors. For applications with challenging available volumes or the wide field of view required, a thin time projection chamber (TPC) associated with a Micromegas readout plane can provide a good tradeoff between compactness and performance. This paper details the design of such a TPC aiming at maximizing primary signal and minimizing track reconstruction artifacts. The results of the measurements performed during a case study addressing the aforementioned applications are discussed. The current works lines and perspectives of the project are also presented.

scholarly journals Numerical Modeling and Performance Evaluation of Standing Wave Thermoacoustic Refrigerators with a Multi-Layered Stack

Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4360
Author(s):  
Umar Nawaz Bhatti ◽  
Salem Bashmal ◽  
Sikandar Khan ◽  
Rached Ben-Mansour
Keyword(s):  
Standing Wave ◽  
Numerical Study ◽  
Temperature Drop ◽  
Acoustic Power ◽  
Heat Energy ◽  
Coefficient Of Performance ◽  
Material Layer ◽  
And Performance ◽  
Stacked Material ◽  
Thermoacoustic Refrigerators

Thermoacoustic refrigerators have huge potential to replace conventional refrigeration systems as an alternative clean refrigeration technology. These devices utilize conversion of acoustic power and heat energy to generate the desired cooling. The stack plays a pivotal role in the performance of Standing Wave Thermoacoustic Refrigerators (SWTARs), as the heat transfer takes place across it. Performance of stacks can be significantly improved by making an arrangement of different materials inside the stack, resulting in anisotropic thermal properties along the length. In the present numerical study, the effect of multi-layered stack on the refrigeration performance of a SWTAR has been evaluated in terms of temperature drop across the stack, acoustic power consumed and device Coefficient of Performance (COP). Two different aspects of multi-layered stack, namely, different material combinations and different lengths of stacked layers, have been investigated. The combinations of four stack materials and length ratios have been investigated. The numerical results showed that multi-layered stacks produce lower refrigeration temperatures, consume less energy and have higher COP value than their homogeneous counterparts. Among all the material combinations of multi-layered stack investigated, stacks composed of a material layer with low thermal conductivity at the ends, i.e., RVC, produced the best performance with an increase of 26.14% in temperature drop value, reduction in the acoustic power consumption by 4.55% and COP enhancement of 5.12%. The results also showed that, for a constant overall length, an increase in length of side stacked material layer results in an increase in values of both temperature drop and COP.

Reduced volume and increased training intensity elevate muscle Na+-K+pump α2-subunit expression as well as short- and long-term work capacity in humans

2009 ◽  
Vol 107 (6) ◽  
pp. 1771-1780 ◽  
Author(s):  
Jens Bangsbo ◽  
Thomas P. Gunnarsson ◽  
Jesper Wendell ◽  
Lars Nybo ◽  
Martin Thomassen
Keyword(s):  
Endurance Training ◽  
Muscle Protein ◽  
Work Capacity ◽  
Control Group ◽  
Muscle Adaptations ◽  
Subunit Expression ◽  
Short And Long Term ◽  
And Performance ◽  
Trained Runners

The present study examined muscle adaptations and alterations in work capacity in endurance-trained runners as a result of a reduced amount of training combined with speed endurance training. For a 6- to 9-wk period, 17 runners were assigned to either a speed endurance group with a 25% reduction in the amount of training but including speed endurance training consisting of six to twelve 30-s sprint runs 3–4 times/wk (SET group n = 12) or a control group ( n = 5), which continued the endurance training (∼55 km/wk). For the SET group, the expression of the muscle Na+-K+pump α2-subunit was 68% higher ( P < 0.05) and the plasma K+level was reduced ( P < 0.05) during repeated intense running after 9 wk. Performance in a 30-s sprint test and the first of the supramaximal exhaustive runs was improved ( P < 0.05) by 7% and 36%, respectively, after the speed endurance training period. In the SET group, maximal O2uptake was unaltered, but the 3-km (3,000-m) time was reduced ( P < 0.05) from 10.4 ± 0.1 to 10.1 ± 0.1 min and the 10-km (10,000-m) time was improved from 37.3 ± 0.4 to 36.3 ± 0.4 min (means ± SE). Muscle protein expression and performance remained unaltered in the control group. The present data suggest that both short- and long-term exercise performances can be improved with a reduction in training volume if speed endurance training is performed and that the Na+-K+pump plays a role in the control of K+homeostasis and in the development of fatigue during repeated high-intensity exercise.

scholarly journals Intracellular Ca2+ Release and Synaptic Plasticity: A Tale of Many Stores

2018 ◽  
Vol 25 (3) ◽  
pp. 208-226 ◽  
Author(s):  
Zahid Padamsey ◽  
William J. Foster ◽  
Nigel J. Emptage
Keyword(s):  
Endoplasmic Reticulum ◽  
Synaptic Plasticity ◽  
Synaptic Function ◽  
Intracellular Organelles ◽  
Short And Long Term ◽  
Central Synapses ◽  
Neural Signaling ◽  
Temporal Extent

Ca2+ is an essential trigger for most forms of synaptic plasticity. Ca2+ signaling occurs not only by Ca2+ entry via plasma membrane channels but also via Ca2+ signals generated by intracellular organelles. These organelles, by dynamically regulating the spatial and temporal extent of Ca2+ elevations within neurons, play a pivotal role in determining the downstream consequences of neural signaling on synaptic function. Here, we review the role of three major intracellular stores: the endoplasmic reticulum, mitochondria, and acidic Ca2+ stores, such as lysosomes, in neuronal Ca2+ signaling and plasticity. We provide a comprehensive account of how Ca2+ release from these stores regulates short- and long-term plasticity at the pre- and postsynaptic terminals of central synapses.

scholarly journals Is “transgenerational response” a hidden cause of failed corporate turnarounds and chronic underperformance?

2017 ◽  
Vol 45 (3) ◽  
pp. 23-29
Author(s):  
John Oliver
Keyword(s):  
Financial Performance ◽  
Case Studies ◽  
Corporate Culture ◽  
Ceo Turnover ◽  
Business Leaders ◽  
Adaptive Responses ◽  
Content Type ◽  
Organizational Policies ◽  
And Performance

Purpose CEO turnover and chronic corporate underperformance are examined through the lens of Transgenerational Response. Design/methodology/approach The criteria for investigating Transgenerational Response in corporations consisted of identifying a Critical Corporate Incident, the number of corporate generations and the resultant corporate financial performance. Findings The evidence presented in the case studies illustrates how a Critical Corporate Incident has produced the consequential effect of chronic financial performance in the years following the incident. Research limitations/implications These case studies have not presented the “actual” adaptive responses, inherited attitudes and behaviours that have subsequently embedded themselves in a new corporate culture, post the Critical Corporate Incident, to the detriment of the long-term health and performance of each firm. Practical implications Examining CEO turnover and chronic corporate underperformance through the lens of Transgenerational Response means that business leaders can identify how a historic event has affected the performance of their firm in subsequent generations. With this knowledge in hand, they will be able to examine the inherited attitudes and behaviours, organizational policies, strategy and adaptive cultural routines that have combined to consolidate the firms chronic under performance. Originality/value This is a highly original, evidence based, idea that has the potential to reshape our current understanding of CEO turnover and underperforming firms. It will help business leaders identify how a historic event has affected the performance of a firm in subsequent generations.

Health, comfort and performance of children in classrooms – New directions for research

2016 ◽  
Vol 26 (8) ◽  
pp. 1040-1050 ◽  
Author(s):  
Philomena M. Bluyssen
Keyword(s):  
School Environment ◽  
Learning Ability ◽  
Toxic Exposure ◽  
Literature Study ◽  
New Directions ◽  
And Performance ◽  
New Generation ◽  
Acoustic Conditions

Children spend more time in schools than in any other place except at home. Children are more susceptible than adults to effects of toxic exposure, but also to poor acoustic conditions. It is known for some time that unsatisfactory environmental conditions, can have both short-term and long-term health effects, and can affect productivity or learning ability of the children. The underlying literature study focusses on the role of the indoor school environment on the health, comfort and performance of children in classrooms. In the last decades, many studies all over the world have been performed to document the indoor environment in classrooms and to examine relations with diseases and disorders. An inventory is made of these studies, major identified issues are discussed and ‘new’ directions of research are proposed. It is concluded that new generation research studies should be focussed on engagement of the children in an active way, preferable in semi-lab environments, and taking account of all aspects and interactions between them.

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