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Cross-fostering does not alter the neurochemistry or behavior of spontaneously hypertensive rats
Fleur M Howells, Leander Bindewald, Vivienne A Russell
Behavioral and Brain Functions , 2009, DOI: 10.1186/1744-9081-5-24
Abstract: SHR/NCrl (Charles River, USA), WKY/NCrl (Charles River, USA) and Sprague Dawley rats (SD/Hsd, Harlan, UK) were bred at the University of Cape Town. Rat pups were cross-fostered on postnatal day 2 (PND 2). Control rats remained with their birth mothers to serve as a reference for their particular strain phenotype. Behavior in the open-field and the elevated-plus maze was assessed between PND 29 and 33. Two days later, rats were decapitated and glutamate-stimulated release of [3H]norepinephrine was determined in prefrontal cortex and hippocampal slices.There was no significant effect of "strain of dam" but there was a significant effect of "pup strain" on all parameters investigated. SHR pups travelled a greater distance in the open field, spent a longer period of time in the inner zone and entered the inner zone of the open-field more frequently than SD or WKY. SD were more active than WKY in the open-field. WKY took longer to enter the inner zone than SHR or SD. In the elevated-plus maze, SHR spent less time in the closed arms, more time in the open arms and entered the open arms more frequently than SD or WKY. There was no difference between WKY and SD behavior in the elevated-plus maze. SHR released significantly more [3H]norepinephrine in response to glutamate than SD or WKY in both hippocampus and prefrontal cortex while SD prefrontal cortex released more [3H]norepinephrine than WKY. SHR were resilient, cross-fostering did not reduce their ADHD-like behavior or change their neurochemistry. Cross-fostering of SD pups onto SHR or WKY dams increased their exploratory behavior without altering their anxiety-like behavior.The ADHD-like behavior of SHR and their neurochemistry is genetically determined and not dependent on nurturing by SHR dams. The similarity between WKY and SD supports the continued use of WKY as a control for SHR and suggests that SD may be a useful additional reference strain for SHR. The fact that SD behaved similarly to WKY in the elevated-plus
New light fighters from Asia on the global markets  [PDF]
Tomá? SCHóBER,Pavel NE?AS,Pavel PULI?
INCAS Bulletin , 2013, DOI: 10.13111/2066-8201.2013.5.1.14
Abstract: The high cost of the latest fighters is having a major impact on world air forces, big or small. For many countries it is a difficult balancing act as it becomes hard to afford enough aircraft to maintain the required force structure. Those air forces have to ask themselves whether they can afford enough fighters to accomplish all the desired missions. Many European Air Forces are in unenviable situation, because they can perform only the basic tasks like training and QRA missions over its own territory with limited possibilities for overseas deployment. This paper evaluates the likelihood of renaissance of the light fighter concept and describes three new Asian supersonics with their advantages and disadvantages. The aim is not to select the best lightweight fighter, but to show that rearming to the light variants of combat aircraft should be a good way for some Air Forces.
Evaluation of Occupational Hearing Loss in Fire Fighters in Tehran
F Asghari,A Fotouhi,A Sharifian,A Karimi
Journal of School of Public Health and Institute of Public Health Research , 2004,
Abstract: Hearing loss is a controversial occupational disease in fire fighters because exposure to hazardous levels of noise in this job is so variable and unpredictable. In this study, audiometric assessments were performed on 117 fire fighters to evaluate their hearing loss. The results showed that the average fire fighter has a characteristic noise-induced threshold shift, with maximum hearing loss occurring at 6000 Hz. The hearing loss at the test frequencies was related to age, although the association exceeded that of general population only in 6000 Hz frequency in left ear (p=0.021). Despite finding a pattern of threshold shift typical of occupational hearing loss, it must be noted that after controlling for age, there was no strong relation between length of time on the job and the degree of hearing loss. It seems that more extensive studies are needed to evaluate this relationship.
Techniques Used by Elite Thai and UK Muay Thai Fighters: An Analysis and Simulation  [PDF]
Tony Myers, Nigel Balmer, Alan Nevill, Yahya Al-Nakeeb
Advances in Physical Education (APE) , 2013, DOI: 10.4236/ape.2013.34029
Abstract: Background: Muay Thai is a combat sport growing in international popularity. Previous research has highlighted marked jurisdictional differences in the judging systems employed, but no studies have compared techniques used by fighters across geographic regions or have been on how these might be a function of the different judging systems employed. This paper aimed to address this issue by examining differences in technique selection and application between Thai and UK Muay Thai fighters using notational analysis. Method: The winners of thirty-two fights involving 16 Thai and 16 UK fighters were analysed. Three multilevel Poisson regression models were used to estimate differences in technique frequency and key performance indicators between Thai and UK fighters. Results: Thai fighters used more attacking and defensive techniques than UK fighters, particularly knees (p < 0.001), roundkicks to the body (p < 0.001), and push kicks (p < 0.001). Thai fighters also tended to catch an opponent’s leg significantly more often than UK fighters (p < 0.001), but UK fighters were significantly more likely to use other defensive techniques. There were also statistically significant interactions between nationality and a range of quality indicators, including delivering techniques at an appropriate distance (p < 0.001), the effectiveness of techniques used (p < 0.001), and returning to a balanced stance (p < 0.001). Conclusions: The results suggested that Thai fighters using better distancing, were more effective and more balanced. The practical implications of findings and their implications for the sport and future research are discussed.
光学透视测量玻璃纤维增强复合材料板离面应变场分布
Optical Perspective Measurement of the Out-of-Plane Strain on the Front and Rear Surfaces of Commercial Glass-Fiber Reinforced Composite Plate
 [PDF]

周延周,贾全杰,刘羽飞,刘运红,吴智新,白玉磊,章云
- , 2015, DOI: 10.7520/1001-4888-14-014
Abstract: 本文通过激光波数扫描干涉测量系统和方法,透视测量商用玻璃纤维增强复合材料板前、后表面的离面应变场分布。实验中分别对有缺陷和无缺陷的商用玻璃纤维增强复合材料样品进行了离面位移场测量和平均轴向正应变场分布计算。无缺陷样品的离面位移场及压缩应变场分布均匀连续,随加载呈现递增压缩变化;有缺陷样品的缺陷周围的离面位移场分布变化无规则,其压缩正应变分布以缺陷孔洞为中心,加载量越大,孔洞周围其压缩正应变值较小的区域越大,压缩正应变集中在远离孔洞的边缘区域,随加载量变化压缩应变场分布无线性规律。实验结果证明,激光波数扫描干涉测量系统和方法准确可靠,它为玻璃纤维增强复合材料板的力学性能测量提供了一个新技术平台。
A new measurement system and related measuring method are proposed in this paper, which can be used to perspectively measure the out of plane strain field distribution on the front and rear surface for commercial glass-fiber reinforced composite, based on laser wave number scanning interferometry. In experiment, measurement of the out of plane displacement field and calculation of the average axial normal strain field distributions were conducted for commercial glass fiber reinforced composite samples with and without defect, respectively. The out of plane displacement field and compression strain field distribution of samples without defect are uniformly continuous, and present change linearly proportional to the applied load. While the out of plane displacement field around the defect of samples with defect presents an irregular variation. Its compression normal strain distribution centered on the defect hole, the greater the applied load is, the bigger the small compression strain area around the hole. The compression strain is concentrated in the area far away from the edge of the hole. Furthermore, the variation of compression strain field distribution is not linearly proportional to the applied load. Experimental results indicate that the proposed measurement system and related measuring method provide a new technical platform for mechanical property measurement of commercial glass fiber reinforced composite
Linear Approximation of Rear Stagnation-point Flow  [PDF]
Chio Chon Kit
Physics , 2013,
Abstract: This paper investigates the nature of the development of two-dimensional steady flow of an incompressible fluid at the rear stagnation-point.
Biomechanical Analysis of Entry, Egress and Loading of a Passenger Vehicle with Rear Hinged Rear Doors  [PDF]
James Shippen
International Journal for Traffic and Transport Engineering , 2012,
Abstract: A biomechanical analysis was undertaken to establish the articulation of the back lumbar region and the loads in the muscles of the back during entry and egress of a passenger vehicle with both forwarded hinged and rear hinged doors. The study was then extended to consider placing an object and retrieving an object from the rear seat of passenger vehicles with either forwarded hinged or rear hinged doors. It was found that loads in the muscles of the back and articulation angles were lower for the vehicle equipped with rear hinged doors than for the same activity in the same model of vehicle with forwarded hinged doors.
Analysis of rear-end risk for driver using vehicle trajectory data  [PDF]
Li Yaping, Lu Jian
- , 2017, DOI: 10.3969/j.issn.1003-7985.2017.02.018
Abstract: To explore the relationship between rear-end crash risk and its influencing factors, on-road experiments were conducted for measuring the individual vehicle trajectory data associated with novice and experienced drivers. The rear-end crash potential probability based on the time to collision was proposed to represent the interpretation of rear-end crash risk. One-way analysis of variance was applied to compare the rear-end crash risks for novice and experienced drivers. The rear-end crash risk models for novice and experienced drivers were respectively developed to identify the effects of contributing factors on the driver rear-end crash risk. Also, the cumulative residual method was used to examine the goodness-of-fit of models. The results show that there is a significant difference in rear-end risk between the novice and experienced drivers. For the novice drivers, three risk factors including the traffic volume, the number of lanes and gender are found to significantly impact on the rear-end crash risk, while significant impact factors for experienced drivers are the vehicle speed and traffic volume. The rear-end crash risk models perform well based on the existing limited data samples.
Vehicle Detection Based on Perspective Transformation Using Rear-View Camera  [PDF]
Shiho Tanaka,Kenichi Yamada,Toshio Ito,Takenao Ohkawa
International Journal of Vehicular Technology , 2011, DOI: 10.1155/2011/279739
Abstract: In recent times, the number of vehicles with a rear-view camera has been increasing. The rear-view camera can be utilized as a sensor for monitoring a collision from behind the vehicle in a driving scene. To prevent rear-end collisions, we have been developing a technology that detects approaching vehicles from images obtained using an onboard rear-view camera. In conventional vehicle detection methods, often, camera-view images are used. However, it is difficult to accurately estimate the position of a distant approaching vehicle using such images. In this paper, we propose an improved method to accurately estimate the position of distant approaching vehicles by using virtual top-view images. The displacement of the vehicle in the top-view image is proportional to its speed. Thus, the proposed method can provide the accurate position of the distant vehicle. We describe the details of the proposed method and its availability by the experiment using actual images. 1. Introduction Recently, the use of active safety technologies has increased, and various driver-assistance systems are in practical use. Systems that use on-board sensors such as radars or cameras to minimize the damage caused by rear-end collisions are an example of active safety measures. However, the number of rear-end collisions still remains high. Therefore, it is necessary to prevent not only head-on but also rear-end vehicular collisions. In order to avoid a rear-end collision, we propose a system where an on-board sensor continuously surveys the rear vehicle and if there may be a possibility of a rear-end collision, the system warns the driver of the approaching rear vehicle by flashing the hazard lamps. We have named this system as a rear collision prevention system, and in this paper, we have proposed a method for detecting an approaching vehicle using an on-board rear-view camera that can be utilized in this system. As the number of vehicles equipped with rear-view cameras for parking has been increasing, camera-based systems are expected to be implemented at a lower cost than radar-based systems; therefore, we decided to use an on-board rear-view camera for detecting rear vehicles. In addition, systems for surveying surroundings equipped with front, right, left, and rear-view cameras are commercially available today. With the increasing number of on-board cameras, research for utilizing these cameras for other active safety systems than just checking surroundings has become active [1, 2]. The study of detecting approaching vehicles from on-board camera images began over 20 years
Mortality and life expectancy of professional fire fighters in Hamburg, Germany: a cohort study 1950 – 2000
Norbert L Wagner, Jürgen Berger, Dieter Flesch-Janys, Peter Koch, Anja K?chel, Michel Peschke, Trude Ossenbach
Environmental Health , 2006, DOI: 10.1186/1476-069x-5-27
Abstract: To study this effect a historic cohort study was conducted to assess mortality and life expectancy of professional fire fighters of the City of Hamburg, Germany. Fire departments and trade unions questioned the validity of existing studies from outside Germany because of specific differences in the professional career. No mortality study had been conducted so far in Germany and only few in Europe. Information on all active and retired fire fighters was extracted from personnel records. To assure completeness of data the cohort was restricted to all fire fighters being active on January 1, 1950 or later. Follow up of the cohort ended on June 30th 2000. Vital status was assessed by personnel records, pension fund records and the German residence registries. Mortality of fire fighters was compared to mortality of the Hamburg and German male population by means of standardized mortality ratios. Life expectancy was calculated using life table analysis. Multivariate proportional hazard models were used to assess the effect of seniority, time from first employment, and other occupational characteristics on mortality.The cohort consists of 4640 fire fighters accumulating 111796 person years. Vital status could be determined for 98.2% of the cohort. By the end of follow up 1052 person were deceased. Standardized Mortality Ratio (SMR) for the total cohort was 0.79 (95% CI, 0.74–0.84) compared to Hamburg reference data and 0.78 (95% CI, 0.74–0.83) compared to National German reference data. Conditional life expectancy of a 30 year old fire fighter was 45.3 years as compared to 42.9 year of a German male in normal population. Job tasks, rank status and early retirement negatively influenced mortality. For fire fighters with comparably short duration of employment the mortality advantage diminished with longer time since first employment. SMR of persons who retired early was 1.25 (95% CI, 1.13–1.60) in reference to the general German population and the SMR of 1.71 (1.18–2.50) in
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