Book reviews     

Friedrich Edding  G. W. Parkyn  Renzo Titone  Oskar Anweiler  Frederic Lilge  John Vaizey  Werner Levi  B. Magierska  Walter Schultze  Mary Ewen Ulich  Ben Morris  Ignacy SzAniawski  G. de Landsheere  M. L. Kellmer Pringle  W. Lenz  Rudolf Haas  John Bradley  Josip Lukatela  M. J. Langeveld  S. Wiegersma  H. H. Stern  H. P. Rickman 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1963,8(3-4):471-498

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《古方言词语例释》指瑕     

傅义春  王本灵 《徐州教育学院学报》2003,18(2):83-85

张喆生的《古方言词语例释》对阅读古代献颇有助益。但也存在出条不当，释义不确，义例不合，引有误等问题。  相似文献   

我国优秀乒乓球人才流动特征分析   总被引：1，自引：0，他引：1  

曹犇  张鲲 《天津体育学院学报》2009,24(3):194-197

通过对新中国成立以来不同时期中国优秀乒乓球人才国内、国外流动方向、范围、规模等方面的研究,探究我国优秀乒乓球人才流动的特征与趋势,结果表明:(1)优秀乒乓球人才流动始终以垂直流动为主要方式;(2)优秀乒乓球人才在国内、国际流动的区域呈现出不均衡的分布趋势;(3)优秀乒乓球人才资源丰富与基层群众文化发展的急需相矛盾、脱节;(4)优秀乒乓球人才职业转换的跨度、范围增大,自主性流动趋势增强;(5)优秀乒乓球人才的流动促进r乒乓球运动全球化整体的发展与提高,推动了中国文化的繁荣与世界文化的全面交融.  相似文献   

陕西省乒乓球产业发展道路探析     

曹犇  雷正方  余娟 《吉林体育学院学报》2011,(6):17-19

通过对原陕西省乒乓球队和各种类型的乒乓球俱乐部的调查,探讨了陕西省各地区乒乓球运动产业开展的现状和出现的新情况。结果发现：双轨制下的陕西省乒乓球运动产业发展是由现阶段陕西省的基本情况决定的;陕西省乒乓球运动产业链主体“金字塔”模式基本形成;现阶段陕西省发展乒乓球俱乐部是可行的,但是乒乓球产业化环境并不完善。  相似文献   

The European university landscape: A micro characterization based on evidence from the Aquameth project   总被引：2，自引：0，他引：2  

Cinzia Daraio  Andrea BonaccorsiAldo Geuna  Benedetto LeporiLaurent Bach  Peter BogetoftMargarida F. Cardoso  Elena Castro-MartinezGustavo Crespi  Ignacio Fernandez de LucioHarold Fried  Adela Garcia-AracilAnnamaria Inzelt  Ben JongbloedGerhard Kempkes  Patrick LlerenaMireille Matt  Maria OlivaresCarsten Pohl  Tarmo RatyMaria J. Rosa  Cláudia S. SarricoLéopold Simar  Stig SlipersaeterPedro N. Teixeira  Philippe Vanden Eeckaut 《Research Policy》2011,40(1):148-164

This paper provides a new and systematic characterization of 488 universities, from 11 European countries: Finland, France, Germany, Hungary, Italy, Netherlands, Norway, Portugal, Spain, Switzerland and UK. Using micro indicators built on the integrated Aquameth database, we characterize the European university landscape according to the following dimensions: history/foundation of university, dynamics of growth, specialization pattern, subject mix, funding composition, offer profile and productivity.  相似文献   

职业院校精准资助工作体系的建构与应用   总被引：1，自引：0，他引：1  

贲能军  顾建华  冯晓峥 《教育与职业》2020,(6):48-51

目前职业院校资助工作存在的突出问题有资助对象认定较为简单、资助实施举措较为单一、资助管理模式较为粗放。据此,文章提出职业院校精准资助工作体系的建构:建构资助对象的精准认定体系、建构资助实施的精准方法体系、建构资助过程的精准管理体系。最后说明了职业院校精准资助工作体系的应用:在资助对象的认定上注重定量与定性结合、在资助实施的方法上满足学生个性化需求、在资助管理的手段上建立信息化工作系统。  相似文献   

中国传媒产业市场结构、行为与绩效分析   总被引：3，自引：1，他引：2  

陈蕾  李本乾 《新闻大学》2005,(3):43-46

据摩根斯坦利全球投资报告的统计分析,建立起世界级有竞争力的大企业,传媒业仅需要8年时间,远远快于医药业、银行、电力、能源等行业。可以说,传媒业已经成为继电子信息、制造业、烟草业之后我国排名第四的国家支柱产业,对其产业状况进  相似文献   

The effectiveness of a 17-week lifestyle intervention on health behaviors among airline pilots during COVID-19     

Daniel Wilson  Matthew Driller  Ben Johnston  Nicholas Gill 《运动与健康科学(英文)》2021,10(3):333

PurposeThe aim of this study was to evaluate the efficacy of a 17-week, 3-component lifestyle intervention for enhancing health behaviors during the coronavirus disease 2019 (COVID-19) pandemic.MethodsA parallel-group (intervention and control) study was conducted amongst 79 airline pilots over a 17-week period during the COVID-19 pandemic. The intervention group (n = 38) received a personalized sleep, dietary, and physical activity (PA) program. The control group (n = 41) received no intervention. Outcome measures for sleep, fruit and vegetable intake, PA, and subjective health were measured though an online survey before and after the 17-week period. The changes in outcome measures were used to determine the efficacy of the intervention.ResultsSignificant main effects for time × group were found for International Physical Activity Questionnaire-walk (p = 0.02) and for all other outcome measures (p < 0.01). The intervention group significantly improved in sleep duration (p < 0.01; d = 1.35), Pittsburgh Sleep Quality Index score (p < 0.01; d = 1.14), moderate-to-vigorous PA (p < 0.01; d = 1.44), fruit and vegetable intake (p < 0.01; d = 2.09), Short Form 12v2 physical score (p < 0.01; d = 1.52), and Short Form 12v2 mental score (p < 0.01; d = 2.09). The control group showed significant negative change for sleep duration, Pittsburgh Sleep Quality Index score, and Short Form 12v2 mental score (p < 0.01).ConclusionResults provide preliminary evidence that a 3-component healthy sleep, eating, and PA intervention elicit improvements in health behaviors and perceived subjective health in pilots and may improve quality of life during an unprecedented global pandemic.  相似文献   

Flow manipulation and cell immobilization for biochemical applications using thermally responsive fluids     

Anil Haraksingh Thilsted  Vahid Bazargan  Nina Piggott  Vivien Measday  Boris Stoeber 《Biomicrofluidics》2012,6(4)

A flow redirection and single cell immobilization method in a microfluidic chip is presented. Microheaters generated localized heating and induced poly(N-isopropylacrylamide) phase transition, creating a hydrogel that blocked a channel or immobilized a single cell. The heaters were activated in sets to redirect flow and exchange the fluid in which an immobilized cell was immersed. A yeast cell was immobilized in hydrogel and a 4′,6-diamidino-2-phenylindole (DAPI) fluorescent stain was introduced using flow redirection. DAPI diffused through the hydrogel and fluorescently labelled the yeast DNA, demonstrating in situ single cell biochemistry by means of immobilization and fluid exchange.The ability to control microfluidic flow is central to nearly all lab-on-a-chip processes. Recent developments in microfluidics either include microchannel based flow control in which microvalves are used to control the passage of fluid,¹ or are based on discrete droplet translocation in which electric fields or thermal gradients are used to determine the droplet path.^{2, 3} Reconfigurable microfluidic systems have certain advantages, including the ability to adapt downstream fluid processes such as sorting to upstream conditions and events. This is especially relevant for work with individual biomolecules and high throughput cell sorting.⁴ Additionally, reconfigurable microfluidic systems allow for rerouting flows around defective areas for high device yield or lifetime and for increasing the device versatility as a single chip design can have a variety of applications.Microvalves often form the basis of flow control systems and use magnetic, electric, piezoelectric, and pneumatic actuation methods.⁵ Many of these designs require complicated fabrication steps and can have large complex structures that limit the scalability or feasability of complex microfluidic systems. Recent work has shown how phase transition of stimuli-responsive hydrogels can be used to actuate a simple valve design.⁶ Beebe et al. demonstrated pH actuated hydrogel valves.⁷ Phase transition of thermosensitive poly(N-isopropylacrylamide) (PNIPAAm) using a heater element was demonstrated by Richter et al.⁸ Phase transition was also achieved by using light actuation by Chen et al.⁹ Electric heating has shown a microflow response time of less than 33 ms.¹¹ Previous work¹⁰ showed the use of microheaters to induce a significant shift in the viscosity of thermosensitive hydrogel to block microchannel flow and deflect a membrane, stopping flow in another microchannel. Additionally, Yu et al.¹² demonstrated thermally actuated valves based on porous polymer monoliths with PNIPAAm. Krishnan and Erickson¹³ showed how reconfigurable optically actuated hydrogel formation can be used to dynamically create highly viscous areas and thus redirect flow with a response time of  ～ 2?s. This process can be used to embed individual biomolecules in hydrogel and suppress diffusion as also demonstrated by others.^{15, 16} Fiddes et al.¹⁴ demonstrated the use of hydrogels to transport immobilized biomolecules in a digital microfluidic system. While the design of Krishnan and Erickson is highly flexible, it requires the use of an optical system and absorption layer to generate a geometric pattern to redirect flow.This paper describes the use of an array of gold microheaters positioned in a single layer polydimethylsiloxane (PDMS) microfluidic network to dynamically control microchannel flow of PNIPAAm solution. Heat generation and thus PNIPAAm phase transition were localized as the microheaters were actuated using pulse width modulation (PWM) of an applied electric potential. Additionally, hydrogel was used to embed and immobilise individual cells, exchange the fluid parts of the microfluidic system in order to expose the cells to particular reagents to carry out an in situ biochemical process. The PDMS microchannel network and the microheater array are shown in Figure ​Figure11.Open in a separate windowFigure 1A sketch of the electrical circuit and a microscope image of the gold microheaters and the PDMS microchannels. The power to the heaters was modulated with a PWM input through a H-bridge. For clarity, the electrical circuit for only the two heaters with gelled PNIPAAm is shown (H1 and V2). There are four heaters (V1-V4) in the “vertical channels” and three heaters (H1-H3) in the “horizontal” channel.The microchannels were fabricated using a patterned mould on a silicon wafer to define PDMS microchannels, as described by DeBusschere et al.¹⁷ and based on previous work.¹⁰ A 25 × 75 mm glass microscope slide served as the remaining wall of the microchannel system as well as the substrate for the microheater array. The gold layer had a thickness of 200 nm and was deposited and patterned using E-beam evaporation and photoresist lift-off.²¹ The gold was patterned to function as connecting electrical conductors as well as the microheaters.It was crucial that the microheater array was aligned with an accuracy of  ～ 20μm with the PDMS microchannel network for good heat localization. The PDMS and glass lid were treated with plasma to activate the surface and alignment was carried out by mounting the microscope slide onto the condenser lens of an inverted microscope (TE-2000 Nikon Instruments). While imaging with a 4× objective, the x, y motorized stage aligned the microchannels to the heaters and the condenser lens was lowered for the glass substrate to contact the PDMS and seal the microchannels.Local phase transition of 10% w/w PNIPAAm solution in the microchannels was achieved by applying a 7 V potential through a H-bridge that received a PWM input at 500 Hz which was modulated using a USB controller (Arduino Mega 2650) and a matlab (Mathworks) GUI. The duty cycle of the PWM input was calibrated for each microheater to account for differences in heater resistances (25?Ω to 52?Ω) due to varying lengths of on-chip connections and slight fabrication inconsistencies, as well as for different flow conditions during device operation. Additionally, thermal cross-talk between heaters required decreasing the PWM input significantly when multiple heaters were activated simultaneously. This allowed confining the areas of cross-linked PNIPAAm to the microheaters, allowing the fluid in other areas to flow freely.By activating the heaters in sets, it was possible to redirect the flow and exchange the fluid in the central area. Figure ​Figure22 demonstrates how the flow direction in the central microchannel area was changed from a stable horizontal flow to a stable vertical flow with a 3 s response time, using only PNIPAAm phase transition. Constant pressures were applied to the inlets to the horizontal channel and to the vertical channels. Activating heaters V1-4 (Figure ​(Figure2,2, left) resulted in flow in the horizontal channel only. Likewise, activating heaters H1 and H2 allowed for flow in the vertical channel only. In this sequence, the fluid in the central microchannel area from one inlet was exchanged with fluid from the other inlet. Additionally, by activating heater H3, a particle could be immobilised during the exchange of fluid as shown in Figure ​Figure33 (top).Open in a separate windowFigure 2Switching between fluid from the horizontal and the vertical channel using hydrogel activation and flow redirection with a response time of 3 s. A pressure of 25 mbar was applied to the inlet of the horizontal channel and a pressure of 20 mbar to the vertical channel. The flow field was determined using particle image velocimetry, in which the displacement of fluorescent seed particles was determined from image pairs generated by laser pulse exposure. Processing was carried out with davis software (LaVision).Open in a separate windowFigure 3A series of microscope images near heater H3 showing: (1a)-(1c) A single yeast cell captured by local PNIPAAm phase transition and immobilized for 5 min before being released. (2a) A single yeast cell was identified for capture by embedding in hydrogel. (2b) The cell as well as the hydrogel displayed fluorescence while embedded due to the introduction of DAPI in the surrounding region. (2c) The diffusion of DAPI towards the cell as the heating power of H3 is reduced after 15 min, showing a DAPI stained yeast cell immobilized.Particle immobilisation in hydrogel and fluid exchange in the central area of the microfluidic network were used to carry out an in situ biochemical process in which a yeast cell injected through one inlet was stained in situ with a 4′,6-diamidino-2-phenylindole (DAPI) solution (Invitrogen), which attached to the DNA of the yeast cell.¹⁸ A solution of yeast cells with a concentration of 5 × 10⁷cells/ml suspended in a 10% w/w PNIPAAm solution was injected through the horizontal channel. A solution of 2μg/l DAPI in a 10% w/w PNIPAAm solution was injected through the vertical channel. A single yeast cell was identified and captured near the central heater, and by deactivating the heaters in the vertical channel, DAPI solution was introduced in the microchannels around the hydrogel. After immobilising the cell for 15 min, the heater was deactivated, releasing the cell in the DAPI solution. This process is shown in Figure ​Figure33 (bottom). The sequence of the heater activation and deactivation in order to immobilize the cell and exchange the fluid is outlined in the supplementary material.²¹Eriksen et al.¹⁵ demonstrated the diffusion of protease K in the porous hydrogel matrix,¹⁹ and it was therefore expected that DAPI fluorescent stain (molecular weight of 350 kDa, Ref. ²⁰) would also diffuse. DAPI diffusion is shown in Figure 3(2b) in which the yeast cell shows fluorescence while embedded in the hydrogel. The yeast cell was released by deactivating the central heater and activating all the others to suppress unwanted flow in the microchannel. As a result, the single cell was fully immersed in the DAPI solution. Immobilization of a single cell allows for selection of a cell that exhibits a certain trait and introduction of a new fluid while maintaining the cell position in the field of view of the microscope such that a biochemical response can be imaged continuously.In summary, a microfluidic chip capable of local heating was used to induce phase transition of PNIPAAm to hydrogel, blocking microchannel flow, and thereby allowing for reconfigurable flow. Additionally, the hydrogel was used to embed and immobilise a single yeast cell. DAPI fluorescent stain was introduced using flow redirection, and it stained the immobilized cell, showing diffusion into the hydrogel. The versatile design of this microfluidic chip permits flow redirection, and is suitable to carry out in situ biochemical reactions on individual cells, demonstrating the potential of this technology for forming large-scale reconfigurable microfluidic networks for biochemical applications.  相似文献   

The effects of exercise in hypoxic and normoxic conditions on endothelin-1 and arterial compliance     

Giles LV  Warburton DE  Esch BT  Fedoruk MN  Rupert JL  Taunton JE 《Journal of sports sciences》2012,30(3):261-267

The purpose of this study was to determine the effects of short-term normoxic and hypoxic exercise on plasma endothelin-1 and nitric oxide levels, and the relationship of arterial compliance and pulmonary artery pressure to endothelin-1. Seven endurance-trained males completed two incremental and two steady-state exercise tests performed at ventilatory threshold in normoxia and hypoxia (fraction of inspired oxygen = 0.14). Plasma endothelin-1was measured throughout steady-state tests. Arterial compliance using applanation tonometry, plasma nitric oxide and pulmonary artery pressure using Doppler echocardiography were measured before and after exercise. Small arterial compliance and pulmonary artery pressure significantly increased following exercise. There were no main effects of condition or time for plasma endothelin-1and nitric oxide levels. There were no significant relationships between plasma endothelin-1 and arterial compliance or pulmonary artery pressure. In conclusion, mechanisms other than the endothelial system may play a role in the exercise-induced changes in small artery compliance in this study population. Moderate hypoxia and a 30-minute steady-state exercise have limited effects on plasma endothelin-1 in endurance-trained males.  相似文献