鞋匠与银行家     

Nina 《初中生》2015,(24):34-35

一个鞋匠每天都在自己的歌声中度过.无论是你看到他,还是听到他的歌声,都会使你觉得很愉快.他非常满意这份职业,甚至觉得这种满足感要胜于当上古希腊的七贤人.与之相反,他的邻居却是个腰缠万贯的银行家,他不但很少唱歌,就连睡眠也很少.白天,他偶尔会打个盹,鞋匠的歌声时常会把他从睡梦中唤醒.于是,银行家便痛苦地抱怨上帝,为何不把睡眠也变为一种类似食品或是饮料那样可以买卖的东西呢.  相似文献   

Hate and harassment in academia: the rising concern of the online environment     

Oksanen  Atte  Celuch  Magdalena  Latikka  Rita  Oksa  Reetta  Savela  Nina 《Higher Education》2022,84(3):541-567

Higher Education - Hostile online communication is a global concern. Academic research and teaching staff are among those professionals who routinely give public comments and are thus vulnerable to...  相似文献   

Language and reading impairments are associated with increased prevalence of non-right-handedness     

Filippo Abbondanza  Philip S. Dale  Carol A. Wang  Marianna E. Hayiou-Thomas  Umar Toseeb  Tanner S. Koomar  Karen G. Wigg  Yu Feng  Kaitlyn M. Price  Elizabeth N. Kerr  Sharon L. Guger  Maureen W. Lovett  Lisa J. Strug  Elsje van Bergen  Conor V. Dolan  J. Bruce Tomblin  Kristina Moll  Gerd Schulte-Körne  Nina Neuhoff  Andreas Warnke  Simon E. Fisher  Cathy L. Barr  Jacob J. Michaelson  Dorret I. Boomsma  Margaret J. Snowling  Charles Hulme  Andrew J. O. Whitehouse  Craig E. Pennell  Dianne F. Newbury  John Stein  Joel B. Talcott  Dorothy V. M. Bishop  Silvia Paracchini 《Child development》2023,94(4):970-984

Handedness has been studied for association with language-related disorders because of its link with language hemispheric dominance. No clear pattern has emerged, possibly because of small samples, publication bias, and heterogeneous criteria across studies. Non-right-handedness (NRH) frequency was assessed in N = 2503 cases with reading and/or language impairment and N = 4316 sex-matched controls identified from 10 distinct cohorts (age range 6–19 years old; European ethnicity) using a priori set criteria. A meta-analysis (N_cases = 1994) showed elevated NRH % in individuals with language/reading impairment compared with controls (OR = 1.21, CI = 1.06–1.39, p = .01). The association between reading/language impairments and NRH could result from shared pathways underlying brain lateralization, handedness, and cognitive functions.  相似文献   

从白金预认证到三星级:中美绿色建筑分等评级程序的比较分析     

郑昕  周南  冯威  叶青 《科学与管理》2014,(6):51-60

2011年,作为全球最大能源使用国以及二氧化碳排放国,中美的建筑业所消耗的能源分别占到全国能源总消耗量的25%和40%。在建筑节能领域,绿色建筑的出现为消除建筑业所带来的对能源以及环境的负面影响提供了解决方法。为了促进绿色建筑的市场转型,推进设计和施工的差异化,中美均制定了国家绿色建筑分等评级程序以及配套政策。1998年,美国绿色建筑协会首次推出能源与环境先导设计(LEED),而中国政府则于2008年建立了中国绿色建筑评价标识(GBEL)。本文对美国LEED与中国GBEL评级程序、流程、评分系统以及扶持政策作了对比分析,研究发现,虽然两国所采用的绿色建筑设计以及操作评级程序的评分等级较为相似,它们在项目管理、评分要求和分配以及扶持政策类型等方面存在差异。美国能源与环境先导设计是由建筑产业利益相关者委员会制定并实施管理的。判断是否达到认证水平的灵活性更高。中国绿色建筑评价标识则是由政府操控的。判断是否达到评级水平的要求更为严格。但是,中国政府将在2014年下半年对中国绿色建筑评价标识的评级程序作出修正。本文对评级程序以及扶植政策的相似点以及差异是如何影响绿色建筑技术以及市场的发展作了分析,还讨论了绿色建筑未来发展可能面临的挑战以及政策导向意义。  相似文献   

Return to play management after concussion in football: recommendations for team physicians     

Nina Feddermann-Demont  Dominik Straumann  Jiří Dvořák 《Journal of sports sciences》2014,32(13):1217-1228

Abstract

A concussion is a rare but potentially serious injury of football players. Thus, an immediate and valid diagnosis, estimate of severity and therapeutic management is required. To summarise the published information on management of concussion with respect to a safe return to play (RTP), a literature search was conducted. Current guidelines on concussion in sports and significant studies on concussion in football were analysed. After concussion, management and RTP decision should remain in the area of clinical judgement on an individualised basis according to the current international guidelines. If a concussion is suspected, the player should not be allowed to RTP the same day. The RTP programme should follow a gradual step-wise procedure. A concussed player should not RTP unless he/she is asymptomatic and the neurological and neuropsychological examinations are normal. Untimely RTP bears an increased risk of sustaining another more severe brain injury and repetitive brain injury of long-term sequelae. In football, the management of concussion should primarily follow the recommendations proposed by the Concussion in Sports Group. Information and education of players and their medical and coaching team help to protect the players’ health. Future studies on concussion should include validated and detailed information on RTP protocols.  相似文献   

English,Si!     

Nina Willis Walter 《College Teaching》2013,61(4):239-240

  相似文献   

101+ Careers in Gerontology (2nd ed.) By C. Joanne Grabinski     

Nina M. Silverstein 《Educational gerontology》2015,41(7):548-549

  相似文献   

Computer-assisted remedial reading intervention for school beginners at risk for reading disability     

Saine NL  Lerkkanen MK  Ahonen T  Tolvanen A  Lyytinen H 《Child development》2011,82(3):1013-1028

The aim of the longitudinal study was to investigate whether a computer application designed for remedial reading training can enhance letter knowledge, reading accuracy, fluency, and spelling of at-risk children. The participants, 7-year-old Finnish school beginners (N=166), were assigned to 1 of 3 groups: (a) regular remedial reading intervention (n=25), (b) computer-assessed reading intervention (n=25), and (c) mainstream reading instruction (n=116). Based on the results, computer-assisted remedial reading intervention was highly beneficial, whereas regular type of intervention was less successful. The results indicated that at-risk children require computer-based letter-name and letter-sound training to acquire adequate decoding and spelling skills, and to reach the level of their non-at-risk peers.  相似文献   

Research Information Literacy: Addressing Original Researchers' Needs     

Nina Exner 《The Journal of Academic Librarianship》2014,40(5):460-466

Information literacy for faculty, doctoral students and other research-based graduate students, post-docs, and other original researchers is complex. There are fundamental differences between the processes of inquiry used by original researchers as compared to students or even faculty who are synthesizing information to find answers. Original research is different from information synthesis for discovery. Therefore, the information literacy processes to train and support those researchers are different. Analysis of the inquiry-oriented parts of the current and emerging information literacy Standards and Framework shows significant differences in the approach needed for teaching research information literacy. Promising instructional outcomes for information literacy training based around original research include gap analysis, theoretical and methodological discovery, and practical skills like funding search and analysis.  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