WorldWideScience

Sample records for catapults

  1. Catapulting tentacles in a sticky carnivorous plant.

    Science.gov (United States)

    Poppinga, Simon; Hartmeyer, Siegfried Richard Heinrich; Seidel, Robin; Masselter, Tom; Hartmeyer, Irmgard; Speck, Thomas

    2012-01-01

    Among trapping mechanisms in carnivorous plants, those termed 'active' have especially fascinated scientists since Charles Darwin's early works because trap movements are involved. Fast snap-trapping and suction of prey are two of the most spectacular examples for how these plants actively catch animals, mainly arthropods, for a substantial nutrient supply. We show that Drosera glanduligera, a sundew from southern Australia, features a sophisticated catapult mechanism: Prey animals walking near the edge of the sundew trigger a touch-sensitive snap-tentacle, which swiftly catapults them onto adjacent sticky glue-tentacles; the insects are then slowly drawn within the concave trap leaf by sticky tentacles. This is the first detailed documentation and analysis of such catapult-flypaper traps in action and highlights a unique and surprisingly complex mechanical adaptation to carnivory. PMID:23049849

  2. Catapulting tentacles in a sticky carnivorous plant.

    Directory of Open Access Journals (Sweden)

    Simon Poppinga

    Full Text Available Among trapping mechanisms in carnivorous plants, those termed 'active' have especially fascinated scientists since Charles Darwin's early works because trap movements are involved. Fast snap-trapping and suction of prey are two of the most spectacular examples for how these plants actively catch animals, mainly arthropods, for a substantial nutrient supply. We show that Drosera glanduligera, a sundew from southern Australia, features a sophisticated catapult mechanism: Prey animals walking near the edge of the sundew trigger a touch-sensitive snap-tentacle, which swiftly catapults them onto adjacent sticky glue-tentacles; the insects are then slowly drawn within the concave trap leaf by sticky tentacles. This is the first detailed documentation and analysis of such catapult-flypaper traps in action and highlights a unique and surprisingly complex mechanical adaptation to carnivory.

  3. Design of Dsppool Based on Catapult C%基于Catapult C的Dsppool设计

    Institute of Scientific and Technical Information of China (English)

    罗锋; 刘新宁

    2009-01-01

    在此使用高级语言进行运算加速模块Dsppool描述,再使用Mentor公司的Catapult C工具完成RTL设计,并为Dsppool模块进行满足APB接口的封装,使之能够作为一个AMBA总线上的Slave模块.实验结果显示,使用硬件描述语言手动设计的Dsppool模块与CatapultC设计的RTL代码功能完全一致,并且综合后性能相当,因为高级语言忽略了硬件设计中的细节,设计速度比直接使用硬件描述语言快几倍到几十倍.

  4. TC-13 Mod 0 and Mod 2 Steam Catapult Test Site

    Data.gov (United States)

    Federal Laboratory Consortium — Located on 11,000 feet of test runway, the TC-13 Mod 0 and Mod 2 Steam Catapult Test Site has in-ground catapults identical to those aboard carriers. This test site...

  5. Concept of an induction-dynamic catapult for a ballistic laser gravimeter

    OpenAIRE

    V.F. Bolyukh; Vinnichenko, A. I.

    2014-01-01

    A design is proposed for an inductive-dynamic catapult in a ballistic laser gravimeter with a fixed inductor and an electrically conducting armature that moves together with the test object along a vertical axis. The catapult ensures improved accuracy of the gravimeter through direct conversion of electrical into kinetic energy. The electrical circuit of the catapult provides two successive current pulses to the inductor for launching and braking of the armature during the operating cycle.

  6. The fern cavitation catapult: mechanism and design principles.

    Science.gov (United States)

    Llorens, C; Argentina, M; Rojas, N; Westbrook, J; Dumais, J; Noblin, X

    2016-01-01

    Leptosporangiate ferns have evolved an ingenious cavitation catapult to disperse their spores. The mechanism relies almost entirely on the annulus, a row of 12-25 cells, which successively: (i) stores energy by evaporation of the cells' content, (ii) triggers the catapult by internal cavitation, and (iii) controls the time scales of energy release to ensure efficient spore ejection. The confluence of these three biomechanical functions within the confines of a single structure suggests a level of sophistication that goes beyond most man-made devices where specific structures or parts rarely serve more than one function. Here, we study in detail the three phases of spore ejection in the sporangia of the fern Polypodium aureum. For each of these phases, we have written the governing equations and measured the key parameters. For the opening of the sporangium, we show that the structural design of the annulus is particularly well suited to inducing bending deformations in response to osmotic volume changes. Moreover, the measured parameters for the osmoelastic design lead to a near-optimal speed of spore ejection (approx. 10 m s(-1)). Our analysis of the trigger mechanism by cavitation points to a critical cavitation pressure of approximately -100 ± 14 bar, a value that matches the most negative pressures recorded in the xylem of plants. Finally, using high-speed imaging, we elucidated the physics leading to the sharp separation of time scales (30 versus 5000 µs) in the closing dynamics. Our results highlight the importance of the precise tuning of the parameters without which the function of the leptosporangium as a catapult would be severely compromised.

  7. The fern cavitation catapult: mechanism and design principles.

    Science.gov (United States)

    Llorens, C; Argentina, M; Rojas, N; Westbrook, J; Dumais, J; Noblin, X

    2016-01-01

    Leptosporangiate ferns have evolved an ingenious cavitation catapult to disperse their spores. The mechanism relies almost entirely on the annulus, a row of 12-25 cells, which successively: (i) stores energy by evaporation of the cells' content, (ii) triggers the catapult by internal cavitation, and (iii) controls the time scales of energy release to ensure efficient spore ejection. The confluence of these three biomechanical functions within the confines of a single structure suggests a level of sophistication that goes beyond most man-made devices where specific structures or parts rarely serve more than one function. Here, we study in detail the three phases of spore ejection in the sporangia of the fern Polypodium aureum. For each of these phases, we have written the governing equations and measured the key parameters. For the opening of the sporangium, we show that the structural design of the annulus is particularly well suited to inducing bending deformations in response to osmotic volume changes. Moreover, the measured parameters for the osmoelastic design lead to a near-optimal speed of spore ejection (approx. 10 m s(-1)). Our analysis of the trigger mechanism by cavitation points to a critical cavitation pressure of approximately -100 ± 14 bar, a value that matches the most negative pressures recorded in the xylem of plants. Finally, using high-speed imaging, we elucidated the physics leading to the sharp separation of time scales (30 versus 5000 µs) in the closing dynamics. Our results highlight the importance of the precise tuning of the parameters without which the function of the leptosporangium as a catapult would be severely compromised. PMID:26763327

  8. Analysis of the Design Criteria for Ancient Greek and Roman Catapults

    DEFF Research Database (Denmark)

    Paasch, Kasper

    2011-01-01

    This paper will give a short overview of use of COMSOL Multiphysics for analyzing ancient Greek and Roman catapults with the main focus on the energy storing torsion springs. Catapults have been known and used in the Greek and Roman world from around 399 BC and a fully standardized design...

  9. Capillary-inertial colloidal catapults upon drop coalescence

    Science.gov (United States)

    Chavez, Roger L.; Liu, Fangjie; Feng, James J.; Chen, Chuan-Hua

    2016-07-01

    Surface energy released upon drop coalescence is known to power the self-propelled jumping of liquid droplets on superhydrophobic solid surfaces, and the jumping droplets can additionally carry colloidal payloads toward self-cleaning. Here, we show that drop coalescence on a spherical particle leads to self-propelled launching of the particle from virtually any solid surface. The main prerequisite is an intermediate wettability of the particle, such that the momentum from the capillary-inertial drop coalescence process can be transferred to the particle. By momentum conservation, the launching velocity of the particle-drop complex is proportional to the capillary-inertial velocity based on the drop radius and to the fraction of the liquid mass in the total mass. The capillary-inertial catapult is not only an alternative mechanism for removing colloidal contaminants, but also a useful model system for studying ballistospore launching.

  10. Principles of laser microdissection and catapulting of histologic specimens and live cells.

    Science.gov (United States)

    Vogel, Alfred; Horneffer, Verena; Lorenz, Kathrin; Linz, Norbert; Hüttmann, Gereon; Gebert, Andreas

    2007-01-01

    Rapid contact- and contamination-free procurement of specific samples of histologic material for proteomic and genomic analysis as well as separation and transport of living cells can be achieved by laser microdissection (LMD) of the sample of interest followed by a laser-induced forward transport process [laser pressure "catapulting," (LPC)] of the dissected material. We investigated the dynamics of LMD and LPC with focused and defocused laser pulses by means of time-resolved photography. The working mechanism of microdissection was found to be plasma-mediated ablation. Catapulting is driven by plasma formation, when tightly focused pulses are used, and by ablation at the bottom of the sample for moderate and strong defocusing. Driving pressures of several hundred megapascals accelerate the specimen to initial velocities of 100-300 m/s before it is rapidly slowed down by air friction. With strong defocusing, driving pressure and initial flight velocity decrease considerably. On the basis of a characterization of the thermal and optical properties of the histologic specimens and supporting materials used, we calculated the temporal evolution of the heat distribution in the sample. After laser microdissection and laser pressure catapulting (LMPC), the samples were inspected by scanning electron microscopy. Catapulting with tightly focused or strongly defocused pulses results in very little collateral damage, while slight defocusing involves significant heat and UV exposure of up to about 10% of the specimen volume, especially if samples are catapulted directly from a glass slide. Time-resolved photography of live-cell catapulting revealed that in defocused catapulting strong shear forces originate from the flow of the thin layer of culture medium covering the cells. By contrast, pulses focused at the periphery of the specimen cause a fast rotational movement that makes the specimen wind its way out of the culture medium, thereby undergoing much less shear stresses

  11. Low Acceleration Overload Catapult Technique for Throwing the Small Scout Robot

    Directory of Open Access Journals (Sweden)

    Jianzhong Wang

    2016-09-01

    Full Text Available The small scout robot is generally thrown into the war zone by soldier. The short thrown distance and the danger of soldier exposed to the enemy limit the application of the small scout robot. So this paper presents a type of low acceleration overload catapult device of no flash, no smoke and no sound. It can throw the small scout robot covertly to long distances with low acceleration overload, and avoid the danger that soldier be exposed to the enemy when artificial throwing. The high and low pressure chambers of the catapult device achieve the low acceleration overload launching, and eliminate the risk of robot damaged by huge acceleration overload. The covert launching of no flash, no smoke and no sound is achieved by the piston to seal the gun propellant gas in barrel. Based on the interior ballistic model, the interior ballistic performance is calculated. The experiment for measuring the acceleration overload of the projectile is achieved by using the catapult device prototype and the measurement system developed by authors. The simulation and test results show that this catapult device can meet the requirement to throw the small scout robot into the war zone.

  12. Open Innovation, Triple Helix and Regional Innovation Systems: Exploring CATAPULT Centres in the UK

    Science.gov (United States)

    Kerry, Christopher; Danson, Michael

    2016-01-01

    Through the lens of UK CATAPULT Centres this conceptual paper presents an examination of the links between open innovation, the Triple Helix model and regional innovation systems. Highlighting the importance of boundary-spanning intermediaries, the combined role of these concepts is explored in detail. A conceptual model is then proposed which…

  13. The Cell Therapy Catapult: growing a U.K. cell therapy industry generating health and wealth.

    Science.gov (United States)

    Thompson, Keith; Foster, Emma Palmer

    2013-12-01

    In a recent report on the regenerative medicine sector, the U.K. House of Lords made several recommendations to enable the United Kingdom to become a global leader in this important industry. Its recommendations in this regard were many and various, covering the regulatory system, clinical trials, manufacturing, funding, approval, and reimbursement. In its mission to tackle what it sees as three main types of barriers to the development of the cell therapy industry in the United Kingdom, the Cell Therapy Catapult is tackling many of these issues. Established as a center of excellence in the United Kingdom in 2012, the Cell Therapy Catapult is a research organization expected to grow to a team of around 100 experts. Its core financing of £ 70 million over the next 5 years is provided by the Technology Strategy Board, the United Kingdom's innovation agency, and with additional contract research income and access to collaborative funds, the Catapult expects to build up to annual revenues of around £ 30 million. Along with its sister Catapult programs in other areas of the economy, the Cell Therapy Catapult was established after identification of the massive early-stage expertise the country has, as well as an acute market failure-the lack of expertise to translate early-stage cell therapy research into commercial success. In this article, in addition to showing our progress so far, we will discuss the hurdles the industry faces-grouped into business, manufacturing/supply chain issues, and clinical/regulatory issues-and what we are doing to help the United Kingdom leap over them. PMID:24304073

  14. Production of aerosols by optical catapulting: Imaging, performance parameters and laser-induced plasma sampling rate

    Energy Technology Data Exchange (ETDEWEB)

    Abdelhamid, M. [National Institute of Laser Enhanced Science, NILES, Cairo University, Giza (Egypt); Fortes, F.J.; Fernández-Bravo, A. [Department of Analytical Chemistry, Faculty of Sciences, University of Malaga, 29071 Malaga (Spain); Harith, M.A. [National Institute of Laser Enhanced Science, NILES, Cairo University, Giza (Egypt); Laserna, J.J., E-mail: laserna@uma.es [Department of Analytical Chemistry, Faculty of Sciences, University of Malaga, 29071 Malaga (Spain)

    2013-11-01

    Optical catapulting (OC) is a sampling and manipulation method that has been extensively studied in applications ranging from single cells in heterogeneous tissue samples to analysis of explosive residues in human fingerprints. Specifically, analysis of the catapulted material by means of laser-induced breakdown spectroscopy (LIBS) offers a promising approach for the inspection of solid particulate matter. In this work, we focus our attention in the experimental parameters to be optimized for a proper aerosol generation while increasing the particle density in the focal region sampled by LIBS. For this purpose we use shadowgraphy visualization as a diagnostic tool. Shadowgraphic images were acquired for studying the evolution and dynamics of solid aerosols produced by OC. Aluminum silicate particles (0.2–8 μm) were ejected from the substrate using a Q-switched Nd:YAG laser at 1064 nm, while time-resolved images recorded the propagation of the generated aerosol. For LIBS analysis and shadowgraphy visualization, a Q-switched Nd:YAG laser at 1064 nm and 532 nm was employed, respectively. Several parameters such as the time delay between pulses and the effect of laser fluence on the aerosol production have been also investigated. After optimization, the particle density in the sampling focal volume increases while improving the aerosol sampling rate till ca. 90%. - Highlights: • Aerosol generation by optical catapulting has been successfully optimized. • We study the evolution and dynamics of solid aerosols produced by OC. • We use shadowgraphy visualization as a diagnostic tool. • Effects of temporal conditions and laser fluence on the elevation of the aerosol cloud have been investigated. • The observed LIBS sampling rate increased from 50% reported before to approximately 90%.

  15. Production of aerosols by optical catapulting: Imaging, performance parameters and laser-induced plasma sampling rate

    International Nuclear Information System (INIS)

    Optical catapulting (OC) is a sampling and manipulation method that has been extensively studied in applications ranging from single cells in heterogeneous tissue samples to analysis of explosive residues in human fingerprints. Specifically, analysis of the catapulted material by means of laser-induced breakdown spectroscopy (LIBS) offers a promising approach for the inspection of solid particulate matter. In this work, we focus our attention in the experimental parameters to be optimized for a proper aerosol generation while increasing the particle density in the focal region sampled by LIBS. For this purpose we use shadowgraphy visualization as a diagnostic tool. Shadowgraphic images were acquired for studying the evolution and dynamics of solid aerosols produced by OC. Aluminum silicate particles (0.2–8 μm) were ejected from the substrate using a Q-switched Nd:YAG laser at 1064 nm, while time-resolved images recorded the propagation of the generated aerosol. For LIBS analysis and shadowgraphy visualization, a Q-switched Nd:YAG laser at 1064 nm and 532 nm was employed, respectively. Several parameters such as the time delay between pulses and the effect of laser fluence on the aerosol production have been also investigated. After optimization, the particle density in the sampling focal volume increases while improving the aerosol sampling rate till ca. 90%. - Highlights: • Aerosol generation by optical catapulting has been successfully optimized. • We study the evolution and dynamics of solid aerosols produced by OC. • We use shadowgraphy visualization as a diagnostic tool. • Effects of temporal conditions and laser fluence on the elevation of the aerosol cloud have been investigated. • The observed LIBS sampling rate increased from 50% reported before to approximately 90%

  16. Multi-agent Based Hierarchy Simulation Models of Carrier-based Aircraft Catapult Launch

    Institute of Scientific and Technical Information of China (English)

    Wang Weijun; Qu Xiangju; Guo Linliang

    2008-01-01

    With the aid of multi-agent based modeling approach to complex systems,the hierarchy simulation models of carrier-based aircraft catapult launch are developed.Ocean,carrier,aircraft,and atmosphere are treated as aggregation agents,the detailed components like catapult,landing gears,and disturbances are considered as meta-agents,which belong to their aggregation agent.Thus,the model with two layers is formed i.e.the aggregation agent layer and the meta-agent layer.The information communication among all agents is described.The meta-agents within one aggregation agent communicate with each other directly by information sharing,but the meta-agents,which belong to different aggregation agents exchange their information through the aggregation layer fast,and then perceive it from the sharing environment,that is the aggregation agent.Thus,not only the hierarchy model is built,but also the environment perceived by each agent is specified.Meanwhile,the problem of balancing the independency of agent and the resource consumption brought by real-time communication within multi-agent system (MAS) is resolved.Each agent involved in carrier-based aircraft catapult launch is depicted,with considering the interaction within disturbed atmospheric environment and multiple motion bodies including carrier,aircraft,and landing gears.The models of reactive agents among them are derived based on tensors,and the perceived messages and inner frameworks of each agent are characterized.Finally,some results of a simulation instance are given.The simulation and modeling of dynamic system based on multi-agent system is of benefit to express physical concepts and logical hierarchy clearly and precisely.The system model can easily draw in kinds of other agents to achieve a precise simulation of more complex system.This modeling technique makes the complex integral dynamic equations of multibodies decompose into parallel operations of single agent,and it is convenient to expand,maintain,and reuse

  17. Assessment and regression analysis on instant catapult steam explosion pretreatment of corn stover.

    Science.gov (United States)

    Liu, Chen-Guang; Liu, Li-Yang; Zi, Li-Han; Zhao, Xin-Qing; Xu, You-Hai; Bai, Feng-Wu

    2014-08-01

    Instant catapult steam explosion (ICSE) offers enormous physical force on lignocellulosic biomass due to its extremely short depressure duration. In this article, the response surface methodology was applied to optimize the effect of working parameters including pressure, maintaining time and mass loading on the crystallinity index and glucose yield of the pretreated corn stover. It was found that the pressure was of essential importance, which determined the physical force that led to the morphological changes without significant chemical reactions, and on the other hand the maintaining time mainly contributed to the thermo-chemical reactions. Furthermore, the pretreated biomass was assessed by scanning electron microscope, X-ray diffraction and Fourier transform infrared spectra to understand mechanisms underlying the ICSE pretreatment.

  18. 技术与创新中心在解决创新的"死亡之谷"问题中的作用——基于对英国Catapults项目实施效果的实证分析%Technology Innovation Centre and Its Role in Addressing the Valley of Death—— Analysis of the Effects of Catapults Program in UK

    Institute of Scientific and Technical Information of China (English)

    李振兴

    2015-01-01

    Catapults program is started and funded by UK government to address the "Valley of Death" of innovation. To date, seven Catapults such as High Value Manufacture Catapult were set up and open to public, another two Catapults named Energy System and Precise Medicine Catapult are under the way to open. The reason of Valley of Death and the unique role of Catapults playing in addressing the Valley of Death were introduced; the economics background of Catapults program and necessity of implementing Catapults program as a public policy tool were analyzed. Cases were given to illustrate how Catapults may help the business development, especially the commercialization of research and development driven by innovation.%为解决创新的"死亡之谷"难题,英国近年投入巨资建设新的技术与创新中心(Catapults).本文从"死亡之谷"的形成原因出发,介绍了技术与创新中心在破解"死亡之谷"难题中发挥的独特作用,并基于已经建成的七个Catapults 的实证,分析了Catapults 项目实施的经济学背景以及作为公共创新政策工具的必要性,通过案例分析介绍了Catapults 在实际运行中如何促进产业发展特别是促进研究商业化和创新发展,供决策参考.

  19. 基于排队论的大型舰船甲板弹射器数量研究%Investigation into Deck Catapults Quantity of Large Ship by Using Queuing Theory

    Institute of Scientific and Technical Information of China (English)

    周鑫磊; 孟祥印; 解学参; 胡玉龙; 侯远杭

    2011-01-01

    The objective of this article is to establish a theoretical basis for determining the quantity of catapult on the flight deck of large ship. As for investigation, the approach of "dummy queue (virtual queue)" was presented from the view of aircraft handling officer, and the task flow model was set up and analysis was carried out by using the queuing theory. The realistic model of task flow of carrier-based aircraft in standby position for launch was also constructed. A multiple calculations were conducted for the key targets, ignoring all the other factors, with regard to the influence of different quantities of catapults on the virtual length of aircraft's waiting queue and time of the system standby based on the assumption of the queuing theory. The results enable to have a quantifying comparison of sortie generation capacities of carried-based aircraft on the flight deck. The calculations also showed that under a given set of conditions, increasing the quantity of the catapult can obviously minimize the queuing length of the birds waiting in a queue for launch on the flight deck, but, if the number of catapult was greater than four, this would be less effective. Through the calculating results, application of the queuing theory to the demonstration as well as quantity design of catapult on large ship is proved to be practicable.%为明确大型舰船飞行甲板弹射器数量设计的理论依据,从调运指挥官的角度提出了"虚拟队列"概念,分析了其工作特点,对其工作模式进行了排队论建模.同时分析、建立了舰载机在弹射等待过程中的真实排队模型.忽略其它甲板因素的影响,基于排队论假设代入数值计算了不同弹射器数量对虚拟队列中舰载机的等待队长、系统等待耗时等关键指标的影响,使弹射器数量影响下的大型舰船舰载机出动能力得到了量化比较.计算结果表明,在给定条件下,甲板弹射器数量的增加能有效减少大型舰船舰

  20. Vortices catapult droplets in atomization

    CERN Document Server

    Jerome, J John Soundar; Matas, Jean-Philippe; Zaleski, Stéphane; Hoepffner, Jérôme

    2016-01-01

    A droplet ejection mechanism in planar two-phase mixing layers is examined. Any disturbance on the gas-liquid interface grows into a Kelvin-Helmholtz wave, and the wave crest forms a thin liquid film that flaps as the wave grows downstream. Increasing the gas speed, it is observed that the film breaks up into droplets which are eventually thrown into the gas stream at large angles. In a flow where most of the momentum is in the horizontal direction, it is surprising to observe these large ejection angles. Our experiments and simulations show that a recirculation region grows downstream of the wave and leads to vortex shedding similar to the wake of a backward-facing step. The ejection mechanism results from the interaction between the liquid film and the vortex shedding sequence: a recirculation zone appears in the wake of the wave and a liquid film emerges from the wave crest; the recirculation region detaches into a vortex and the gas flow over the wave momentarily reattaches due to the departure of the vor...

  1. Dancing through the School Day: How Dance Catapults Learning in Elementary Education

    Science.gov (United States)

    Becker, Kelly Mancini

    2013-01-01

    The necessity for engaging the body in learning, the need for students to move throughout the school day, and the positive effects that dance has on students' development are all good reasons for dance to be included in the elementary curriculum. There are many ways for teachers to integrate movement into the school day, using math, science,…

  2. Katapultos: Teaching Basic Statistics with Ballistics.

    Science.gov (United States)

    Fitzgerald, Mike

    2001-01-01

    Describes the use of catapults as a way to increase math, science, and technology correlations within the classroom. Includes detailed instructions, a list of materials for building a catapult, and print and Internet resources. (JOW)

  3. Holy graal of physics

    CERN Document Server

    Bührke, Thomas

    2006-01-01

    With the biggest "catapult" for elementar particles, the physicists want to explain why there is actually matter. Like in the USA some years ago, big accelerator started to find that black light would perhaps exist. (1 page)

  4. Brazil World Cup Challenges

    Directory of Open Access Journals (Sweden)

    MANSUR, R.

    2012-12-01

    Full Text Available Overcoming the productivity challenge is the main benefit of the 2014 World Cup for Brazilian people. The sustainable development of our cultural tourism industry will catapult the new middle class growing up rate.

  5. Principles of laser-induced separation and transport of living cells.

    Science.gov (United States)

    Horneffer, Verena; Linz, Norbert; Vogel, Alfred

    2007-01-01

    Separation and transport of defined populations of living cells grown on a thin membrane can be achieved by laser microdissection (LMD) of the sample of interest, followed by a laser-induced forward transport process [laser pressure "catapulting" (LPC)] of the dissected cell cluster. We investigate the dynamics of LMD and LPC with focused and defocused UV-A laser pulses by means of time-resolved photography. Catapulting is driven by plasma formation when tightly focused pulses are used, and by confined thermal ablation at the bottom of the sample for defocused catapulting. With both modalities, the initial specimen velocity amounts to about 50 to 60 ms. Time-resolved photography of live cell catapulting reveals that in defocused catapulting, strong shear forces arise when the sample is accelerated out of the culture medium covering the cells. By contrast, pulses focused at the periphery of the specimen cause a fast rotational movement that minimizes the flow of culture medium parallel to the sample surface, and thus the resulting shear stresses. Therefore, the recultivation rate of catapulted cells is much higher when focused pulses are used. Compared to collateral damage by mechanical forces, side effects by heat and UV exposure of the cells play only a minor role.

  6. The Future of Technology in Health Education: Challenging the Traditional Delivery Dogma

    Science.gov (United States)

    Kittleson, Mark J.

    2009-01-01

    The author has been blessed with an opportunity to contribute to the profession of health education via a technology that 20 years ago did not exist. The HEDIR catapulted him into the national limelight. He created the HEDIR in 1992--the profession's first email directory and listserv. The profession has found the HEDIR to be an exceptional tool…

  7. Hypermediated Art Criticism

    Science.gov (United States)

    Taylor, Pamela G.; Carpenter, B. Stephen, II

    2007-01-01

    Technological media catapults our perception into what Marshall McLuhan called "new transforming vision and awareness." As our lives become more and more immersed in such technologies as television, film, and interactive computers, we find ourselves inundated with a heightened sense of mindfulness--an aesthetic experience made possible through…

  8. Physics Notes.

    Science.gov (United States)

    School Science Review, 1979

    1979-01-01

    Included is information regarding: fabrication of light emitting diodes, their operation as semiconductors, and an experiment demonstrating electroluminescence; experimenting with Random Access Memory (RAM) circuits; demonstrating Coriolis effect; measuring the diameter of an electron beam, E.H.T. meters; launching a trolley by catapult; a "random…

  9. The OECD as Pivot of the Emerging Global Educational Accountability Regime: How Accountable Are the Accountants?

    Science.gov (United States)

    Meyer, Heinz-Dieter

    2014-01-01

    Background/Context: PISA has catapulted the OECD- an organization whose mission is the global growth of market economies-to a central role in international education policy making, rivaling and sometimes outdoing the various national governments in influence. While claiming scientific evidence as the basis for the accountability regime it…

  10. Using pico-LCoS SLMs for high speed cell sorting

    DEFF Research Database (Denmark)

    Bañas, Andrew Rafael; Aabo, Thomas; Palima, Darwin;

    2012-01-01

    We propose the use of consumer pico projectors as cost effective spatial light modulators in cell sorting applications. The matched filtering Generalized Phase Contrast (mGPC) beam shaping method is used to produce high intensity optical spots for trapping and catapulting cells. A pico projector...

  11. Safety First: Safety--The Elementary Mission

    Science.gov (United States)

    Roy, Ken

    2013-01-01

    Activities involving the construction of a model solar oven, soda bottle rocket, catapult, bridge, roller coaster, playground, and plane glider all have one thing in common. They are examples of STEM project activities for elementary students. STEM is one of the areas of emphasis in the "Next Generation Science Standards" (NGSS), which…

  12. The past and future of RRI

    NARCIS (Netherlands)

    Rip, Arie

    2014-01-01

    Within the space of a few years, the idea of Responsible Research and Innovation, and its acronym RRI, catapulted from an obscure phrase to the topic of conferences and attempts to specify and realize it. How did this come about, and against which backdrop? What are the dynamics at present, and what

  13. Muscle-tendon interaction and elastic energy usage in human walking

    DEFF Research Database (Denmark)

    Ishikawa, Masaki; Komi, Paavo V.; Grey, Michael James;

    2005-01-01

    The present study was designed to explore how the interaction between the fascicles and tendinous tissues is involved in storage and utilization of elastic energy during human walking. Eight male subjects walked with a natural cadence (1.4 +/- 0.1 m/s) on a 10-m-long force plate system. In vivo......-stance phase. In contrast, the soleus fascicles were lengthened until the end of the single-stance phase. These findings suggest that the elastic recoil takes place not as a spring-like bouncing but as a catapult action in natural human walking. The interaction between the muscle fascicles and tendinous...... tissues plays an important role in the process of release of elastic energy, although the leg muscles, which are commonly accepted as synergists, do not have similar mechanical behavior of fascicles in this catapult action....

  14. Quantum leaps of black holes: Magnifying glasses of quantum gravity

    CERN Document Server

    Chakraborty, Sumanta

    2016-01-01

    We show using simple arguments, that the conceptual triad of a {\\it classical} black hole, semi-classical Hawking emission and geometry quantization is inherently, mutually incompatible. Presence of any two explicitly violates the third. We argue that geometry quantization, if realized in nature, magnifies the quantum gravity features hugely to catapult them into the realm of observational possibilities. We also explore a quantum route towards extremality of the black holes.

  15. Antibody Labelling of Resilin in Energy Stores for Jumping in Plant Sucking Insects

    OpenAIRE

    Malcolm Burrows; Jolanta A Borycz; Shaw, Stephen R; Elvin, Christopher M.; Meinertzhagen, Ian A.

    2011-01-01

    The rubbery protein resilin appears to form an integral part of the energy storage structures that enable many insects to jump by using a catapult mechanism. In plant sucking bugs that jump (Hemiptera, Auchenorrhyncha), the energy generated by the slow contractions of huge thoracic jumping muscles is stored by bending composite bow-shaped parts of the internal thoracic skeleton. Sudden recoil of these bows powers the rapid and simultaneous movements of both hind legs that in turn propel a jum...

  16. Efficient lossy compression implementations of hyperspectral images: tools, hardware platforms, and comparisons

    Science.gov (United States)

    García, Aday; Santos, Lucana; López, Sebastián.; Callicó, Gustavo M.; Lopez, Jose F.; Sarmiento, Roberto

    2014-05-01

    Efficient onboard satellite hyperspectral image compression represents a necessity and a challenge for current and future space missions. Therefore, it is mandatory to provide hardware implementations for this type of algorithms in order to achieve the constraints required for onboard compression. In this work, we implement the Lossy Compression for Exomars (LCE) algorithm on an FPGA by means of high-level synthesis (HSL) in order to shorten the design cycle. Specifically, we use CatapultC HLS tool to obtain a VHDL description of the LCE algorithm from C-language specifications. Two different approaches are followed for HLS: on one hand, introducing the whole C-language description in CatapultC and on the other hand, splitting the C-language description in functional modules to be implemented independently with CatapultC, connecting and controlling them by an RTL description code without HLS. In both cases the goal is to obtain an FPGA implementation. We explain the several changes applied to the original Clanguage source code in order to optimize the results obtained by CatapultC for both approaches. Experimental results show low area occupancy of less than 15% for a SRAM-based Virtex-5 FPGA and a maximum frequency above 80 MHz. Additionally, the LCE compressor was implemented into an RTAX2000S antifuse-based FPGA, showing an area occupancy of 75% and a frequency around 53 MHz. All these serve to demonstrate that the LCE algorithm can be efficiently executed on an FPGA onboard a satellite. A comparison between both implementation approaches is also provided. The performance of the algorithm is finally compared with implementations on other technologies, specifically a graphics processing unit (GPU) and a single-threaded CPU.

  17. Producing Popularity: The Success in France of the Comics Series "Astérix le Gaulois"

    OpenAIRE

    Dandridge, Eliza Bourque

    2008-01-01

    This study examines the rise in popularity of the French comics series "Astérix le Gaulois" through a production-of-culture lens in an effort to uncover how industry evolution and organization, protectionist legislation, marketing, advertising, branding, and consecration by the media worked interdependently to catapult Astérix, the series' protagonist, into stardom by the middle of the 1960s. In so doing, this study forcefully argues that elements external to the text itself greatly facilit...

  18. Traian Vuia – the Romanian inventor who first flew a powered airplane in 1906

    Directory of Open Access Journals (Sweden)

    Liviu FILIMON

    2011-09-01

    Full Text Available As observed the beginning of heavier than air devices started with Wright Brothers who flew in 1903 the first catapulted airplane equipped with an engine, similar to present motor gliders. In March 1906 took place the first flight of Vuia’s monoplane using on board installations. Since then a real competition between manufacturers has started to improve their airplanes as they become more efficient. Traian Vuia’s first flights and his beginnings are explained below.

  19. Book review: JFK in the senate: pathway to the presidency

    OpenAIRE

    Polo Alonso, Ana

    2013-01-01

    Before John F. Kennedy became a legendary young President, he was the junior Senator from Massachusetts. The Senate was where JFK’s presidential ambitions were born and first realized. In this forthcoming book, John T. Shaw looks at how the young Senator was able to catapult himself on the national stage. JFK in the Senate aims to provide an accessible introduction to Kennedy’s personality and his efforts to transform himself into a viable presidential candidate, and it will certainly appeal ...

  20. Chemical characterization of single micro- and nano-particles by optical catapulting–optical trapping–laser-induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Spectral identification of individual micro- and nano-sized particles by the sequential intervention of optical catapulting, optical trapping and laser-induced breakdown spectroscopy is presented. The three techniques are used for different purposes. Optical catapulting (OC) serves to put the particulate material under inspection in aerosol form. Optical trapping (OT) permits the isolation and manipulation of individual particles from the aerosol, which are subsequently analyzed by laser-induced breakdown spectroscopy (LIBS). Once catapulted, the dynamics of particle trapping depends both on the laser beam characteristics (power and intensity gradient) and on the particle properties (size, mass and shape). Particles are stably trapped in air at atmospheric pressure and can be conveniently manipulated for a precise positioning for LIBS analysis. The spectra acquired from the individually trapped particles permit a straightforward identification of the material inspected. Variability of LIBS signal for the inspection of Ni microspheres was 30% relative standard deviation. OC–OT–LIBS permits the separation of particles in a heterogeneous mixture and the subsequent analysis of the isolated particle of interest. In order to evaluate the sensitivity of the approach, the number of absolute photons emitted by a single trapped particle was calculated. The limit of detection (LOD) for Al2O3 particles was calculated to be 200 attograms aluminium. - Highlights: • Detection of single nanoparticles by OC–OT–LIBS has been described for the first time. • An absolute mass quantity of 17 fg (single particle 100-nm sized Al2O3) was detected. • Results confirm the extreme sensitivity of LIBS for single nanoparticle analysis. • The LOD for Al2O3 particles was calculated to be 200 attograms aluminium. • A photon budget was performed in order to evaluate the sensitivity of the approach

  1. Take-off speed in jumping mantises depends on body size and a power-limited mechanism

    Science.gov (United States)

    Doroshenko, M.; Cullen, D. A.; Burrows, M.

    2016-01-01

    ABSTRACT Many insects such as fleas, froghoppers and grasshoppers use a catapult mechanism to jump, and a direct consequence of this is that their take-off velocities are independent of their mass. In contrast, insects such as mantises, caddis flies and bush crickets propel their jumps by direct muscle contractions. What constrains the jumping performance of insects that use this second mechanism? To answer this question, the jumping performance of the mantis Stagmomantis theophila was measured through all its developmental stages, from 5 mg first instar nymphs to 1200 mg adults. Older and heavier mantises have longer hind and middle legs and higher take-off velocities than younger and lighter mantises. The length of the propulsive hind and middle legs scaled approximately isometrically with body mass (exponent=0.29 and 0.32, respectively). The front legs, which do not contribute to propulsion, scaled with an exponent of 0.37. Take-off velocity increased with increasing body mass (exponent=0.12). Time to accelerate increased and maximum acceleration decreased, but the measured power that a given mass of jumping muscle produced remained constant throughout all stages. Mathematical models were used to distinguish between three possible limitations to the scaling relationships: first, an energy-limited model (which explains catapult jumpers); second, a power-limited model; and third, an acceleration-limited model. Only the model limited by muscle power explained the experimental data. Therefore, the two biomechanical mechanisms impose different limitations on jumping: those involving direct muscle contractions (mantises) are constrained by muscle power, whereas those involving catapult mechanisms are constrained by muscle energy. PMID:27284067

  2. Wind energy barometer - EurObserv'ER - February 2016

    International Nuclear Information System (INIS)

    The spectacular rise of China's wind power market that resulted in connecting at least 30.5 GW, catapulted the global installation level to 62.7 GW in 2015- a 22% more than in 2014. The US and German markets also performed very well, the former because its tax credit mechanism remained in force and the latter because many of its offshore wind farms in the North Sea were connected to the grid. Global wind turbine capacity has increased by 17% and now stands at 432.6 GW

  3. Computer Forensics JumpStart

    CERN Document Server

    Solomon, Michael G; Tittel, Ed; Broom, Neil; Barrett, Diane

    2011-01-01

    Essential reading for launching a career in computer forensicsInternet crime is on the rise, catapulting the need for computer forensics specialists. This new edition presents you with a completely updated overview of the basic skills that are required as a computer forensics professional. The author team of technology security veterans introduces the latest software and tools that exist and they review the available certifications in this growing segment of IT that can help take your career to a new level. A variety of real-world practices take you behind the scenes to look at the root causes

  4. A Tale of Two Kirzners: Time, Uncertainty and the Nature of Opportunities

    DEFF Research Database (Denmark)

    Korsgaard, Steffen; Berglund, Henrik; Thrane, Claus;

    2015-01-01

    This paper discusses the influence of Israel Kirzner on the field of entrepreneurship research. We review Kirzner’s work and argue that it contains two distinct approaches to entrepreneurship, termed Kirzner Mark I and Kirzner Mark II. Mark I with its focus on alertness and opportunity discovery...... has exerted a strong influence on entrepreneurship research in the last decade, and helped catapult the field forward. We propose that Mark II, with its emphasis on time, uncertainty and creative action in pursuit of imagined opportunities, complements the discovery view and can provide an alternative...

  5. Western armament and tactics in the writings of Anna Komnene

    Directory of Open Access Journals (Sweden)

    Drašković Marko

    2006-01-01

    Full Text Available In this work, first we reconstructed and commented the western horseman's armament witch Anna Komnene had known (long spear, cross-bow, chain mail "Norman" shield, solarets. Afterwards, we established that Anne knew four types of western horseman's attack (attack in full gallop, attack from back slow march, attack from flank and three types of their battle formation (strewn formation, congested formation, formation of two columns. Also, we commented Anna's knowledge of western siege engines (battering-ram, tortoise catapult, siege tower; we established that Anne knew five types of western siege tower. In the end, we commented several fragments witch show Anna Komnene's knowledge of the western siege tactics.

  6. A NASA study of the impact of technology on future carrier based tactical aircraft - Overview

    Science.gov (United States)

    Wilson, S. B., III

    1992-01-01

    This paper examines the impact of technology on future carrier based tactical aircraft. The results were used in the Center for Naval Analysis Future Carrier Study. The NASA Team designed three classes of aircraft ('Fighter', 'Attack', and 'Multimission') with two different technology levels. The Multimission aircraft were further analyzed by examining the penalty on the aircraft for both catapult launch/arrested landing recovery (Cat/trap) and short take-off/vertical landing (STOVL). The study showed the so-called STOVL penalty was reduced by engine technology and the next generation Strike Fighter will pay more penalty for Cat/trap than for STOVL capability.

  7. Performance studies on the application of four-engine and two-engine USB propulsive lift to the E-2C aircraft

    Science.gov (United States)

    Riddle, D. W.; Stevens, V. C.

    1986-01-01

    A study has been completed of the performance benefits to be derived from applying advanced upper-surface blowing (USB) propulsive-lift technology to the E-2C aircraft. The results of comparing four-engine with two-engine USB configurations are discussed, and engine sizing and aerodynamic/structural considerations pertaining to the E-2C/USB modification are examined. The effects of the modification on performance are described in detail with regard to takeoff distance and landing distance estimation in free-deck operations, operations using catapult and arresting gear, ceiling and radar surveillance missions, and range and endurance capability.

  8. FAST-FISH with laser beam microdissected DOP-PCR probe distinguishes the sex chromosomes of Silene latifolia.

    Science.gov (United States)

    Hobza, Roman; Lengerova, Martina; Cernohorska, Halina; Rubes, Jiri; Vyskot, Boris

    2004-01-01

    We present an improved FISH strategy for differentiating the sex chromosomes of the dioecious model plant, Silene latifolia. Fixed mitotic protoplasts were dropped on a polyethylene naphthalate membrane, the X or Y chromosomes were isolated using nitrogen laser beam microdissection, catapulted by laser pressure, and amplified by DOP-PCR. A modified FAST-FISH protocol based on a short hybridization time combined with a low concentration of probe was used. The success of this approach is demonstrated by the differential labeling of the X and Y chromosomes and it could represent a quick method for comparing organization of plant genomes. PMID:15125638

  9. 汽车结构

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Development of a vehicle structure with enhanced pedestrian safety;Door slam Cycle Tests of an automobile structure;Dynamic interaction of vehicles moving on uniform bridge;Dynamical actions on highway bridge decks due to an irregular pavement surface;Electric Drive System for Electric and Hybrid Vehicles;Energy absorption and performance of a vehicle impact protection system;Fatigue strength evaluation on resistance spot welds of the vbehicle body;HyperG - a new hydro-pneumatic, catapult-type sled;Integration of a terrain-adaptive traction control system in the hierarchy of locomotion control system;……

  10. Adrenal lesions encountered in current medical practice − a review of their radiological imaging

    Directory of Open Access Journals (Sweden)

    Vanesha Naidu

    2013-11-01

    Full Text Available Modern radiological technology has transformed the way that adrenal lesions are currently investigated. The contemporary radiologist has been catapulted to the forefront in the management of adrenal disease. With the increasing use of cross-sectional imaging, adrenal lesions are being serendipitously discovered in radiological studies undertaken for non-adrenal-related conditions – the so-called adrenal ‘incidentaloma’. This review discusses the imaging modalities available for characterising these lesions, highlighting current concepts and controversies in differentiating benign from malignant pathology. The article also provides a brief overview of the spectrum of adrenal pathology commonly encountered in the adult population.

  11. Vietnam 2035

    OpenAIRE

    World Bank; Ministry of Planning and Investment of Vietnam

    2016-01-01

    OVERVIEW. FULL BOOK EXPECTED LATER IN 2016. The year 2015 marks 70 years since Vietnam’s Declaration of Independence, 40 years since reunification, and just short of 30 years from the launch of Doi Moi reforms, which catapulted the nation from the ranks of the world’s poorest to one of the great development success stories. Critical ingredients of success have been visionary leaders, a sense of shared societal purpose, and a focus on the future. Starting in the late 1980s, these elemen...

  12. 我所知道的——关于踩槌的一切(四)

    Institute of Scientific and Technical Information of China (English)

    李果

    2008-01-01

    而台湾的GIBRALTAR新研发的GCLMSP Catapult Linear Motion Bass Drum Pedal[图044]也因为其古怪的制动方式被我归入此类,这样说起来,SONOR的Gtep 3 Giant Step Twin Effect Pedal[图045]、Gtep 3 Giant Step Triple Pedal [图046]、GMP 4 Giant Step Middle Pedal[图047]也绝对属于此例。

  13. Mechanical Enterogenesis - A Review

    Directory of Open Access Journals (Sweden)

    Rebecca Stark

    2012-01-01

    Full Text Available Mechanical enterogenesis is a novel method of lengthening pre-existing intestine with distractive force. The application of mechanical force on small intestine aims to induce cellular proliferation and ultimately increase bowel length. This has been investigated primarily for the treatment of short bowel syndrome (SBS. Research has been ongoing for well over a decade in this arena and a multitude of advances have been made, both in the understanding of the biology behind force induced cellular proliferation and in the basic mechanics of force delivery systems. Important experimental models have been developed for studying this phenomenon and the collaboration of engineers and medical researchers has lead to the design of several devices that successfully lengthen small intestine. This has catapulted the field forward and there may soon be a device suitable for medical use in humans. This review analyses the past, present and future of mechanical enterogenesis.

  14. What makes a champion! over fifty extraordinary individuals share their insights

    CERN Document Server

    2014-01-01

    What drives great and successful individuals — be they athletes, artists, or scientists — or businesses, to achieve the extraordinary? Over fifty champions from all walks of life, brought together by Allan Snyder, draw on their experiences to explore the secrets of success in this inspiring, revealing and thought-provoking book. Hear from the authors what made a McDonalds' branch become the most successful in the world; how a cottage business is catapulted into a world brand; how a visual artist's works crosses almost every medium imaginable; how an Ernst and Young setup becomes a top-notch employer; or why many geniuses or brilliant individuals never become champions, while many 'ordinary' individuals do; why many people don't know about their talent; what constitutes a champion outcome; and the neurological explanation for championship. Straddling academia and practitioners in all fields — government, entertainment, sports, business, arts, education, medicine, media — the authors include business...

  15. Machine-vision based optofluidic cell sorting

    DEFF Research Database (Denmark)

    Glückstad, Jesper; Bañas, Andrew

    In contemporary life science there is an increasing emphasis on sorting rare disease-indicating cells within small dilute quantities such as in the confines of optofluidic lab-on-chip devices. Our approach to this is based on the use of optical forces to isolate red blood cells detected by advanced...... machine vision1. This approach is gentler, less invasive and more economical compared to conventional FACS-systems. As cells are less responsive to plastic or glass objects commonly used in the optical manipulation literature2, and since laser safety would be an issue in clinical use, we develop efficient...... the available light and creating 2D or 3D beam distributions aimed at the positions of the detected cells. Furthermore, the beam shaping freedom provided by GPC can allow optimizations in the beam’s propagation and its interaction with the laser catapulted and sorted cells....

  16. Transient inactivation of Rb and ARF yields regenerative cells from postmitotic mammalian muscle.

    Science.gov (United States)

    Pajcini, Kostandin V; Corbel, Stephane Y; Sage, Julien; Pomerantz, Jason H; Blau, Helen M

    2010-08-01

    An outstanding biological question is why tissue regeneration in mammals is limited, whereas urodele amphibians and teleost fish regenerate major structures, largely by cell cycle reentry. Upon inactivation of Rb, proliferation of postmitotic urodele skeletal muscle is induced, whereas in mammalian muscle this mechanism does not exist. We postulated that a tumor suppressor present in mammals but absent in regenerative vertebrates, the Ink4a product ARF (alternative reading frame), is a regeneration suppressor. Concomitant inactivation of Arf and Rb led to mammalian muscle cell cycle reentry, loss of differentiation properties, and upregulation of cytokinetic machinery. Single postmitotic myocytes were isolated by laser micro-dissection-catapulting, and transient suppression of Arf and Rb yielded myoblast colonies that retained the ability to differentiate and fuse into myofibers upon transplantation in vivo. These results show that differentiation of mammalian cells is reversed by inactivation of Arf and Rb and support the hypothesis that Arf evolved at the expense of regeneration. PMID:20682446

  17. A bright point source of ultrashort hard x-rays from laser bioplasmas

    CERN Document Server

    Krishnamurthy, M; Lad, Amit D; Ahmad, Saima; Narayanan, V; Rajeev, R; Kundu, M; Kumar, G Ravindra; Ray, Krishanu

    2010-01-01

    Micro and nano structures scatter light and amplify local electric fields very effectively. Energy incident as intense ultrashort laser pulses can be converted to x-rays and hot electrons more efficiently with a substrate that suitably modifies the local fields. Here we demonstrate that coating a plain glass surface with a few micron thick layer of an ubiquitous microbe, {\\it Escherichia coli}, catapults the brightness of hard x-ray bremsstrahlung emission (up to 300 keV) by more than two orders of magnitude at an incident laser intensity of 10$^{16}$ W cm$^{-2}$. This increased yield is attributed to the local enhancement of electric fields around individual {\\it E. coli} cells and is reproduced by detailed particle-in-cell (PIC) simulations. This combination of laser plasmas and biological targets can lead to turnkey, multi-kilohertz and environmentally safe sources of hard x-rays.

  18. Nanotechnology in dentistry: reduction to practice.

    Science.gov (United States)

    Ure, David; Harris, Jonathan

    2003-01-01

    The speed at which advances are being made in science has catapulted nanotechnology from its theoretical foundations straight into the real world. There are now many examples of commercially available products demonstrating that, in given situations, the technology really does work and that its scope for further application is wide. Healthcare, along with society as a whole, is facing a major revolution in the wake of ongoing technological developments in the field of nanotechnology. Dentistry as an individual healthcare discipline is not exempt, having already been targeted directly with novel 'nano-materials' at the same time as indirectly enjoying the benefits of nano-related advances in the electronics industry through the ongoing computerization of the modern practice. This article examines current practical applications of nanotechnology alongside proposed applications in the future and aims to demonstrate that, as well as a good deal of science fiction, there is some tangible science fact emerging from this novel multi-disciplinary science.

  19. Don Winslow, autor de un clásico y otras obras dentro de la narconarrativa mexicano-estadounidense (una guía para forasteros

    Directory of Open Access Journals (Sweden)

    Arturo E. García Niño

    2015-12-01

    Full Text Available Anclado en lo que se ha dado en llamar la narconarrativa, una expresión literaria binacional fronteriza compartida por México y Estados Unidos, se encuentra Don Winslow, quien con su novela El poder del perro catapultó y cimentó el enunciado subgénero literario para, de ahí, generar otras novelas que tienen al crimen organizado, y sus relaciones con el mundo empresarial y político, como protagonista y tópico, así como a la frontera como espacio donde se desarrollan los hechos narrados. Y sobre la narconarrativa, sobre el autor enunciado, su obra y el contexto binacional versa el análisis aquí incluido

  20. Balancing Energy, Food, Natural Resources and Environment in Nepal

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Dilli Bahadur

    2010-09-15

    Nepal could harness less than 1% of its 83000 MW hydropower potential. Pancheshwar Multipurpose Project (6720 MW) is a bi-national project on Mahakali River bordering between Nepal and India. The earnings from: electricity (NRs. 34.55 billion/year); irrigation (NRs. 5.55 billion/year), fish farming (NRs. 8.65 billion/year), carbon trading (NRs. 4.42 billion/year) and many billions from other sources e.g. eco-tourism, industry, horticulture, herbiculture, floriculture, sericulture, rafting and water sports, educational and vocational training and other industrial/commercial activities can catapult the socioeconomic horizon of Nepal. Hence, PMP should be jointly developed in the earliest and build confidence for the further hydropower development.

  1. Ocean sciences after September 11

    Science.gov (United States)

    McPhaden, Michael J.

    The terrorist attacks in New York City and Washington D.C. on September 11, 2001 shocked the world with their audacity and destruction. Shortly thereafter, bioterrorists struck through the U.S. postal system. Virtually overnight, major policy shifts took place in the United States that catapulted national security and homeland defense to the top of the political agenda. The consequences were unimaginable just a few months before: an international coalition at war against the Taliban in Afghanistan, major increases in U.S. defense spending, tightened security measures at airports, government facilities, and research laboratories, and a new sense of vulnerability in the post-cold war era. AGU itself was directly affected: three of its members perished in the hijacked planes, or on the ground in New York City.

  2. Statistical visualization of the Earth's magnetotail based on Geotail data and the implied substorm model

    Directory of Open Access Journals (Sweden)

    S. Machida

    2009-03-01

    Full Text Available We investigated the temporal and spatial development of the near-Earth magnetotail during substorms based on multi-dimensional superposed-epoch analysis of Geotail data. The start time of the auroral break-up (t=0 of each substorm was determined from auroral data obtained by the Polar and IMAGE spacecraft. The key parameters derived from the plasma, magnetic-field, and electric-field data from Geotail were sorted by their meridional X(GSM–Z(proxy coordinates.

    The results show that the Poynting flux toward the plasma-sheet center starts at least 10 min before the substorm onset, and is further enhanced at X~−12 RE (Earth radii around 4 min before the onset. Simultaneously, large-amplitude fluctuations occurred, and earthward flows in the central plasma sheet between X~−11 RE and X~−19 RE and a duskward flow around X=−10 RE were enhanced. The total pressure starts to decrease around X=−16 RE about 4 min before the onset of the substorm. After the substorm onset, a notable dipolarization is observed and tailward flows commence, characterised by southward magnetic fields in the form of a plasmoid.

    We confirm various observable-parameter variations based on or predicted by the relevant substorm models; however, none of these can explain our results perfectly. Therefore, we propose a catapult (slingshot current-sheet relaxation model, in which an earthward convective flow produced by catapult current-sheet relaxation and a converted duskward flow near the Earth are enhanced through flow braking around 4 min before the substorm onset. These flows induce a ballooning instability or other instabilities, causing the observed current disruption. The formation of the magnetic neutral line is a natural consequence of the present model, because the relaxation of a highly stretched

  3. Interaction of two differently sized oscillating bubbles in a free field.

    Science.gov (United States)

    Chew, Lup Wai; Klaseboer, Evert; Ohl, Siew-Wan; Khoo, Boo Cheong

    2011-12-01

    Most real life bubble dynamics applications involve multiple bubbles, for example, in cavitation erosion prevention, ultrasonic baths, underwater warfare, and medical applications involving microbubble contrast agents. Most scientific dealings with bubble-bubble interaction focus on two similarly sized bubbles. In this study, the interaction between two oscillating differently sized bubbles (generated in tap water) is studied using high speed photography. Four types of bubble behavior were observed, namely, jetting toward each other, jetting away from each other, bubble coalescence, and a behavior termed the "catapult" effect. In-phase bubbles jet toward each other, while out-of-phase bubbles jet away from each other. There exists a critical phase difference that separates the two regimes. The behavior of the bubbles is fully characterized by their dimensionless separation distance, their phase difference, and their size ratio. It is also found that for bubbles with large size difference, the smaller bubble behaves similarly to a single bubble oscillating near a free surface.

  4. The past and future of RRI.

    Science.gov (United States)

    Rip, Arie

    2014-01-01

    Within the space of a few years, the idea of Responsible Research and Innovation, and its acronym RRI, catapulted from an obscure phrase to the topic of conferences and attempts to specify and realize it. How did this come about, and against which backdrop? What are the dynamics at present, and what do these imply for the future of RRI as a discourse, and as a patchwork of practices? It is a social innovation which creates opening in existing (and evolving) divisions of moral labour, a notion that is explained with the help of the history of responsibility language. It is filled in for the present situation and ongoing developments. Some elements may stabilize and this creates a path into the future. There will be reductions of the originally open-ended innovation, some productive, others less so. This is a reason to regularly inquire into the value of the reductions and the directions the path is taking. PMID:26573982

  5. Progress on Concepts for Next-Generation Drop Tower Systems

    Science.gov (United States)

    Könemann, Thorben; Eigenbrod, Christian; Von Kampen, Peter; Laemmerzahl, Claus; Kaczmarczik, Ulrich

    2016-07-01

    The Center of Applied Space Technology and Microgravity (ZARM) founded by Prof. Dr.-Ing. Hans J. Rath in 1985 is part of the Department of Production Engineering at the University of Bremen, Germany. ZARM is mainly concentrated on fundamental investigations of gravitational and space-related phenomenas under conditions of weightlessness as well as questions and developments related to technologies for space. At ZARM about 100 scientists, engineers, and administrative staff as well as many students from different departments are employed. Today, ZARM is still one of the largest and most important research center for space sciences and technologies in Europe. With a height of 146 m the Bremen Drop Tower is the predominant facility of ZARM and also the only drop tower of its class in Europe. ZARM's ground-based laboratory offers the opportunity for daily short-term experiments under conditions of high-quality weightlessness at a level of 10-6 g (microgravity), which is one of the best achievable for ground-based flight opportunities. Scientists may choose up to three times a day between a single drop experiment with 4.74 s in simple free fall and an experiment in ZARM's worldwide unique catapult system with 9.3 s in weightlessness. Since the start of operation of the facility in 1990, over 7500 drops or catapult launches of more than 160 different experiment types from various scientific fields like fundamental physics, combustion, fluid dynamics, planetary formation / astrophysics, biology and materials sciences have been accomplished so far. In addition, more and more technology tests have been conducted under microgravity conditions at the Bremen Drop Tower in order to effectively prepare appropriate space missions in advance. In this paper we report on the progress on concepts for next-generation drop tower systems based on the GraviTower idea utilizing a guided electro-magnetic linear drive. Alternative concepts motivated by the scientific demand for higher

  6. Mechanism for rapid passive-dynamic prey capture in a pitcher plant.

    Science.gov (United States)

    Bauer, Ulrike; Paulin, Marion; Robert, Daniel; Sutton, Gregory P

    2015-10-27

    Plants use rapid movements to disperse seed, spores, or pollen and catch animal prey. Most rapid-release mechanisms only work once and, if repeatable, regaining the prerelease state is a slow and costly process. We present an encompassing mechanism for a rapid, repeatable, passive-dynamic motion used by a carnivorous pitcher plant to catch prey. Nepenthes gracilis uses the impact of rain drops to catapult insects from the underside of the canopy-like pitcher lid into the fluid-filled trap below. High-speed video and laser vibrometry revealed that the lid acts as a torsional spring system, driven by rain drops. During the initial downstroke, the tip of the lid reached peak velocities similar to fast animal motions and an order of magnitude faster than the snap traps of Venus flytraps and catapulting tentacles of the sundew Drosera glanduligera. In contrast to these active movements, the N. gracilis lid oscillation requires neither mechanical preloading nor metabolic energy, and its repeatability is only limited by the intensity and duration of rainfall. The underside of the lid is coated with friction-reducing wax crystals, making insects more vulnerable to perturbations. We show that the trapping success of N. gracilis relies on the combination of material stiffness adapted for momentum transfer and the antiadhesive properties of the wax crystal surface. The impact-driven oscillation of the N. gracilis lid represents a new kind of rapid plant movement with adaptive function. Our findings establish the existence of a continuum between active and passive trapping mechanisms in carnivorous plants. PMID:26438874

  7. Fast Transit Access to the Outer Solar System

    Science.gov (United States)

    Squire, Jared; Bering, Edgar; Giambusso, Matthew; Carter, Mark; Ilin, Andrew; Diaz, Franklin R. Chang

    2015-11-01

    We explore the capability of a VASIMR® reusable probe “catapult” concept to send a 4000-5000 kg spacecraft to Jupiter on a Hohmann-like transfer orbit, arriving in just 36 months elapsed time. The VASIMR® performs a slingshot pass close to the Sun and uses the high level of available solar energy to produce a sustained burst of high thrust. Enough kinetic energy is provided to the probe to reach Jupiter orbit within 0.7-1.4 AU. The Catapult release the probe with enough speed to reach Jupiter in three years, and returns to Earth for another mission. This study identifies the important parameters in the probe ejector operation (power level, propellant mass, payload release point, distance of closest approach to the Sun), and scan these parameters to understand and optimize the capabilities of the proposed system. We assume that the Catapult and its payload begin at the Earth’s sphere of influence (SOI), and are coasting in the Earth’s orbit about the Sun. The VASIMR® engine’s power rating must match the peak power available when the spacecraft is closest to the Sun. The solar array is assumed to be a planar array rather than a concentrator since it will have to operate near the Sun, where a concentrator would overheat photovoltaic cells. The feasibility of not releasing the payload and using the VASIMR® to provide thrust for the duration of the transfer orbit will also be examined. In this scenario, the VASIMR® RF generators could serve double duty as radar RF sources.

  8. Analysis on the Dynamic Characteristics of Carrier-based Aircraft Nose Landing Gear with Sudden Holdback Load Discharge%舰载机弹射起飞前起落架牵制载荷突卸动力学分析

    Institute of Scientific and Technical Information of China (English)

    于浩; 聂宏; 魏小辉

    2011-01-01

    舰载机弹射起飞过程中,由于牵制载荷突卸而产生的前起落架沿航向的快速振动会给机体结构和设备都带来严重的疲劳问题,为研究该振动现象并提出解决方案,建立了舰载机弹射起飞动力学模型,分析计算了前起落架的受载情况,并详细论述其动力学成因,推导了消除前起落架振动现象的充分必要条件.研究结果表明:牵制载荷沿下扭力臂轴向的载荷分量所造成的缓冲器活塞杆的向后弯曲是导致牵制载荷突卸后前起落架振动的主要原因;牵制载荷突卸后,起落架的前后振动导致起落架与机身铰接处的载荷快速、大幅的振荡,对机体结构以及机载设备的寿命和使用安全都会产生不利影响;牵制杆的长度直接影响牵制载荷沿下扭力臂轴向的载荷分量,降低该载荷分量可以有效地解决前起落架由于牵制载荷突卸所带来的振动问题.%The vibration of a nose landing gear caused by the sudden discharge of holdback load during the catapult launch of a carrier-based aircraft could bring serious fatigue both to the structure of the launch and the airborne equipment. To investigate the vibration and seek a solution, a dynamic model of the catapult launch is established. The load of the nose landing gear is calculated, while the kinetics and the way to deal with the phenomenon is also discussed in detail. From the catapult launch calculation, three important conclusions are obtained: during the tension stage, there is a long stroke and aft bending of the nose landing gear; once the holdback load suddenly discharges, the landing gear strut extends and springs forward rapidly; the fore-aft vibration of the nose landing gear produces a rapid and drastic load change at the joint of the gear and the fuselage. This vibration load has an adverse effect on the life and safety of the structure and the equipment of the aircraft. The length of the holdback bar influences the load

  9. Microgravity Experiment Programs for Students at the Bremen Drop Tower

    Science.gov (United States)

    Könemann, Thorben; Eigenbrod, Christian; Von Kampen, Peter; Laemmerzahl, Claus

    The Center of Applied Space Technology and Microgravity (ZARM) founded by Prof. Dr.-Ing. Hans J. Rath in 1985 is part of the Department of Production Engineering at the University of Bremen, Germany. ZARM established as a research center and currently headed by Prof. Dr. Claus Lämmerzahl is mainly concentrated on fundamental investigations of gravitational and space-related phenomenas under conditions of weightlessness as well as questions and developments related to technologies for space. At ZARM more than 70 scientists, engineers and administrative staff as well as many students from different departments are employed. Today, ZARM is still one of the largest and most important university institutes for space sciences and technologies in Europe as well as worldwide well known in the space community. With a height of 146 m the Bremen Drop Tower is the predominant facility of ZARM and also the only drop tower of its class in Europe. ZARM’s ground-based laboratory offers the opportunity for daily short-term experiments under conditions of high-quality weightlessness at a level of 10 (-6) g (microgravity). The provided quality is one of the purest for experiments under weightlessness worldwide achieved. The scientists may choose between a single drop experiment with 4.74 s in simple free fall and a catapult experiment with 9.3 s of weightlessness. Either in the drop or in the worldwide unique catapult operation routine the repetition rates of microgravity experiments at ZARM are always the same, generally up to 3 times per day. Since the start of operation of the facility in 1990, over 6750 launches of more than 160 different experiment types from various scientific fields like Fundamental Physics, Combustion, Fluid Dynamics, Planetary Formation / Astrophysics, Biology and Materials Sciences have been successfully accomplished so far. In our paper we will report and inform about microgravity experiment programs for students like „Drop Your Thesis!“ by ESA and

  10. The Problem with Hitler. The Man Nobody Knows

    Directory of Open Access Journals (Sweden)

    Ben Novak

    2009-12-01

    Full Text Available Conocemos mucho sobre Adolf Hitler. Probablemente tenemos más información –hechos, detalles y horarios- sobre la vida de este hombre que la de cualquier otra figura significativa de la contemporaneidad. Sin embargo, todavía sentimos que desconocemos a este hombre. Su vida es uno de los mayores misterios en la historia de la Humanidad. ¿Por qué Hitler, sobre el que conocemos mayores hechos y detalles que ninguna otra figura en la historia contemporánea (quizás en la historia, permanece siendo un misterio? Hitler frustró a sus oponentes, sorprendió a observadores neutrales, y deleitó a sus seguidores consiguiendo lo “imposible”. Él jamás habría accedido al poder sin haber conseguido estos cinco “improbabilidades” que describiremos a continuación, y lo que es más, consiguiendo el apoyo incondicional de sus seguidores, le dio un aura de excepcionalidad y catapultó a este pequeño y feo hombre al poder. Este artículo tratará sobre esas cinco “improbabilidades” y su influencia en la personalidad de Hitler: sus primeros años (1919-1923; el juicio por el Putsch; la refundación del partido; el terremoto político de 1930 y su ascenso al poder._____________________ABSTRACT:We know so much about Adolf Hitler. We probably have more information—facts, details, and minutiae—about this man’s life than any other major figure of modern times. Nonetheless, we still feel that we do not know the man. His life is one of the greatest mysteries in human history. Why is it that Hitler, about whom more facts and details are known than perhaps any other figure in modern history (perhaps in all history, remains such a mystery?  Hitler frustrated his opponents, amazed neutral observers, and delighted his supporters by pulling off the seemingly “impossible”. He never would have made it into power except by accomplishing these five “impossibilities”; and it was this, more than anything else, that bound his supporters to him

  11. Cell sorting using efficient light shaping approaches

    Science.gov (United States)

    Bañas, Andrew; Palima, Darwin; Villangca, Mark; Glückstad, Jesper

    2016-03-01

    Early detection of diseases can save lives. Hence, there is emphasis in sorting rare disease-indicating cells within small dilute quantities such as in the confines of lab-on-a-chip devices. In our work, we use optical forces to isolate red blood cells detected by machine vision. This approach is gentler, less invasive and more economical compared to conventional FACS systems. As cells are less responsive to plastic or glass beads commonly used in the optical manipulation literature, and since laser safety would be an issue in clinical use, we develop efficient approaches in utilizing lasers and light modulation devices. The Generalized Phase Contrast (GPC) method that can be used for efficiently illuminating spatial light modulators or creating well-defined contiguous optical traps is supplemented by diffractive techniques capable of integrating the available light and creating 2D or 3D beam distributions aimed at the positions of the detected cells. Furthermore, the beam shaping freedom provided by GPC can allow optimizations in the beam's propagation and its interaction with the catapulted cells.

  12. Yachting club

    CERN Multimedia

    Yachting club

    2011-01-01

    WARNING: your C key is about to expire... Good, we hoped that would draw your attention! A gentle reminder that, following the purchase of our fast, sophisticated racing catamaran Hobie Tiger Meerkat last season, your Committee decided to create a new key to reflect this, the EC (Experienced Catamaran). Those taking a C course will be assessed during a test as to whether they will gain the C key or the C plus EC key, so need only practise hard. Those - and we are many - who possess the C key from past years need to refresh our knowledge and prove our competence to sail Meerkat effectively with the EC key. This requires a few attested outings under good wind conditions, use of the gennaker, general control. And if it’s any consolation, we (remembering the Darts and then the Mysteres, and now both SL16 and Tiger) can confirm that she is really a pussycat, and really very willing to tack if you treat her right... Plan on trying for her or indeed Catapult on Thursdays, then talk to your Committee (f.i...

  13. Slow, fast and furious: understanding the physics of plant movements.

    Science.gov (United States)

    Forterre, Yoël

    2013-11-01

    The ability of plants to move is central to many physiological processes from development to tropisms, from nutrition to reproduction. The movement of plants or plant parts occurs over a wide range of sizes and time scales. This review summarizes the main physical mechanisms plants use to achieve motility, highlighting recent work at the frontier of biology and physics on rapid movements. Emphasis is given to presenting in a single framework pioneering biological studies of water transport and growth with more recent physics research on poroelasticity and mechanical instabilities. First, the basic osmotic and hydration/dehydration motors are described that contribute to movement by growth and reversible swelling/shrinking of cells and tissues. The speeds of these water-driven movements are shown to be ultimately limited by the transport of water through the plant body. Some plant structures overcome this hydraulic limit to achieve much faster movement by using a mechanical instability. The principle is to impose an 'energy barrier' to the system, which can originate from geometrical constraint or matter cohesion, allowing elastic potential energy to be stored until the barrier is overcome, then rapidly transformed into kinetic energy. Three of these rapid motion mechanisms have been elucidated recently and are described here: the snapping traps of two carnivorous plants, the Venus flytrap and Utricularia, and the catapult of fern sporangia. Finally, movement mechanisms are reconsidered in the context of the timescale of important physiological processes at the cellular and molecular level. PMID:23913956

  14. Strain-Promoted 1,3-Dipolar Cycloaddition of Cycloalkynes and Organic Azides.

    Science.gov (United States)

    Dommerholt, Jan; Rutjes, Floris P J T; van Delft, Floris L

    2016-04-01

    A nearly forgotten reaction discovered more than 60 years ago-the cycloaddition of a cyclic alkyne and an organic azide, leading to an aromatic triazole-enjoys a remarkable popularity. Originally discovered out of pure chemical curiosity, and dusted off early this century as an efficient and clean bioconjugation tool, the usefulness of cyclooctyne-azide cycloaddition is now adopted in a wide range of fields of chemical science and beyond. Its ease of operation, broad solvent compatibility, 100 % atom efficiency, and the high stability of the resulting triazole product, just to name a few aspects, have catapulted this so-called strain-promoted azide-alkyne cycloaddition (SPAAC) right into the top-shelf of the toolbox of chemical biologists, material scientists, biotechnologists, medicinal chemists, and more. In this chapter, a brief historic overview of cycloalkynes is provided first, along with the main synthetic strategies to prepare cycloalkynes and their chemical reactivities. Core aspects of the strain-promoted reaction of cycloalkynes with azides are covered, as well as tools to achieve further reaction acceleration by means of modulation of cycloalkyne structure, nature of azide, and choice of solvent. PMID:27573141

  15. Pharmacodynamics and Systems Pharmacology Approaches to Repurposing Drugs in the Wake of Global Health Burden.

    Science.gov (United States)

    Bai, Jane P F

    2016-10-01

    There are emergent needs for cost-effective treatment worldwide, for which repurposing to develop a drug with existing marketing approval of disease(s) for new disease(s) is a valid option. Although strategic mining of electronic health records has produced real-world evidences to inform drug repurposing, using omics data (drug and disease), knowledge base of protein interactions, and database of transcription factors have been explored. Structured integration of all the existing data under the framework of drug repurposing will facilitate decision making. The ability to foresee the need to integrate new data types produced by emergent technologies and to enable data connectivity in the context of human biology and targeted diseases, as well as to use the existing crucial quality data of all approved drugs will catapult the number of drugs being successfully repurposed. However, translational pharmacodynamics databases for modeling information across human biology in the context of host factors are lacking and are critically needed for drug repurposing to improve global public health, especially for the efforts to combat neglected tropic diseases as well as emergent infectious diseases such as Zika or Ebola virus. PMID:27522921

  16. Direct Lorentz force compensation flowmeter for electrolytes

    Science.gov (United States)

    Vasilyan, S.; Froehlich, Th.

    2014-12-01

    A simplified method of contactless Lorentz force (LF) measurements for flow meters on electrolytes is described and realized. Modification and comparative representation are discussed against recently well-developed methods. Based on the catapult effect, that current carrying conductor experiences a repulsive force in a magnetic field, we demonstrate force measurement method of LF velocimetry applications by commonly known "electromagnetic force" compensation principle. Measurement approach through zero point stability is considered to minimize mechanical influences and avoid gravimetric uncertainties. Here, the current carrying wires are static fixed in the vicinity of magnet system at zero point stable position, while occurring deflection of magnets by electrolyte flow is compensated by external applied current within wires. Measurements performed by developed servo-system which drives control loop by means of optical position sensor for simplified (i) single wire and (ii) coil-like extended compensation schemes. Guided by experiments on electrolyte flow, we demonstrate the applicability of adopted principle for conductivities ranging from 2 to 20 S/m. Further improvements are discussed in agreement with the parameters of demonstration setup, straightforward theory, and experimental results. We argue that this method is potentially suitable for: (a) applications with higher conductivity like molten metal (order of 106 S/m) assuming spatial configuration of setup and (b) for lower range of conductivity (below 1 S/m) while this is strongly subject to stiffness of system and noise mainly mechanical and thermal radiations.

  17. Interaction of two differently sized oscillating bubbles in a free field.

    Science.gov (United States)

    Chew, Lup Wai; Klaseboer, Evert; Ohl, Siew-Wan; Khoo, Boo Cheong

    2011-12-01

    Most real life bubble dynamics applications involve multiple bubbles, for example, in cavitation erosion prevention, ultrasonic baths, underwater warfare, and medical applications involving microbubble contrast agents. Most scientific dealings with bubble-bubble interaction focus on two similarly sized bubbles. In this study, the interaction between two oscillating differently sized bubbles (generated in tap water) is studied using high speed photography. Four types of bubble behavior were observed, namely, jetting toward each other, jetting away from each other, bubble coalescence, and a behavior termed the "catapult" effect. In-phase bubbles jet toward each other, while out-of-phase bubbles jet away from each other. There exists a critical phase difference that separates the two regimes. The behavior of the bubbles is fully characterized by their dimensionless separation distance, their phase difference, and their size ratio. It is also found that for bubbles with large size difference, the smaller bubble behaves similarly to a single bubble oscillating near a free surface. PMID:22304190

  18. 小型气象无人机作业与起降方式试验研究%Tests of Takeoff and Landing Approach Of Small Meteorological UAV

    Institute of Scientific and Technical Information of China (English)

    吴朝晖; 刘志平; 马瑞升; 孙涵; 林宗桂

    2011-01-01

    通过对比分析2003年以来6种气象无人机起飞和5种降落方式的飞行测试,得出30Kg以下无人机的起飞和降落方式对场地的要求,以及优点和不足;试验证明,弹射起飞和伞降与滑降相结合的回收方式在民用领域中适应性最好,可广泛用于我国的山地、丘陵和平原地形环境,是经济性、安全性俱佳的小型无人机起降方式。%Basing the MUAV (Meteorological Unmanned Aerial Vehicle) flight tests of six kinds of takeoff and 5 kinds of landing approach, the space requirements for MUAV takeoff and landing were discussed, as well as the strengths and weaknesses. It shows that catapult takeoff and the recovery way of parachute combined with downhill race made a best adaptation to the civil field, which can be widely used in China's mountains, hills and plains terrain environment.

  19. Direct Lorentz force compensation flowmeter for electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Vasilyan, S., E-mail: suren.vasilyan@tu-ilmenau.de; Froehlich, Th. [Institute of Process Measurement and Sensor Technology, Ilmenau University of Technology, 98684 Ilmenau (Germany)

    2014-12-01

    A simplified method of contactless Lorentz force (LF) measurements for flow meters on electrolytes is described and realized. Modification and comparative representation are discussed against recently well-developed methods. Based on the catapult effect, that current carrying conductor experiences a repulsive force in a magnetic field, we demonstrate force measurement method of LF velocimetry applications by commonly known “electromagnetic force” compensation principle. Measurement approach through zero point stability is considered to minimize mechanical influences and avoid gravimetric uncertainties. Here, the current carrying wires are static fixed in the vicinity of magnet system at zero point stable position, while occurring deflection of magnets by electrolyte flow is compensated by external applied current within wires. Measurements performed by developed servo-system which drives control loop by means of optical position sensor for simplified (i) single wire and (ii) coil-like extended compensation schemes. Guided by experiments on electrolyte flow, we demonstrate the applicability of adopted principle for conductivities ranging from 2 to 20 S/m. Further improvements are discussed in agreement with the parameters of demonstration setup, straightforward theory, and experimental results. We argue that this method is potentially suitable for: (a) applications with higher conductivity like molten metal (order of 10{sup 6 }S/m) assuming spatial configuration of setup and (b) for lower range of conductivity (below 1 S/m) while this is strongly subject to stiffness of system and noise mainly mechanical and thermal radiations.

  20. Unraveling the Stuxnet Effect: Of Much Persistence and Little Change in the Cyber Threats Debate

    Directory of Open Access Journals (Sweden)

    Myriam Dunn Cavelty

    2011-12-01

    Full Text Available Cyber threats have been on the security political agenda for a number of years. In 2010, Stuxnet, the sophisticated computer worm written to sabotage systems that control and monitor industrial processes stirred up the international community in major ways and catapulted the cyber topic into the sphere of public fears and to the top of everybody’s threat list. As a result, more and more countries consider cyber attacks to be one, if not the major future security threat. This article aims to provide a balanced picture of the phenomenon of cyberwar. It will show how and why the meaning of “cyberwar” has evolved from the narrow conception referring exclusively to military interaction to its broad meaning, which has become detached from “war” and encompasses almost every activity linked to the aggressive use of computers. In particular, it will distinguish between different forms of cyber conflict in order to lay the ground for a levelheaded threat assessment. It further shows that there is probably less change and more persistence in the cyber threat debate at large than is currently acknowledged. The threat image has been quite solid since the late 1990s, and Stuxnet has not changed this to any substantial degree. The same can be said for the countermeasures that are planned or envisaged.

  1. Dynamic tensile failure mechanics of the musculoskeletal neck using a cadaver model.

    Science.gov (United States)

    Yliniemi, Eno M; Pellettiere, Joseph A; Doczy, Erica J; Nuckley, David J; Perry, Chris E; Ching, Randal P

    2009-05-01

    Although the catapult phase of pilot ejections has been well characterized in terms of human response to compressive forces, the effect of the forces on the human body during the ensuing ejection phases (including windblast and parachute opening shock) has not been thoroughly investigated. Both windblast and parachute opening shock have been shown to induce dynamic tensile forces in the human cervical spine. However, the human tolerance to such loading is not well known. Therefore, the main objective of this research project was to measure human tensile neck failure mechanics to provide data for computational modeling, anthropometric test device development, and improved tensile injury criteria. Twelve human cadaver specimens, including four females and eight males with a mean age of 50.1+/-9 years, were subjected to dynamic tensile loading through the musculoskeletal neck until failure occurred. Failure load, failure strain, and tensile stiffness were measured and correlated with injury type and location. The mean failure load for the 12 specimens was 3100+/-645 N, mean failure strain was 16.7+/-5.4%, and mean tensile stiffness was 172+/-54.5 N/mm. The majority of injuries (8) occurred in the upper cervical spine (Oc-C3), and none took place in the midcervical region (C3-C5). The results of this study assist in filling the existing void in dynamic tensile injury data and will aid in developing improved neck injury prevention strategies. PMID:19388771

  2. Dal protettore al controllore. Uno sguardo sociologico sulla letteratura disegnata a tema supereroistico

    Directory of Open Access Journals (Sweden)

    Pier Paolo Zampieri

    2015-12-01

    Full Text Available 1938: a flying man with an S on his breast appears in the sky of an American metropolis, catapulting cartoon mass entertainment into a new dimension. 1986: a spot of blood on a Smiley icon (Moore, 1986 puts an end to the innocence of an entire narrative genre. The two logos, which share a great retroactive symbolic impact, are presented as the two great epistemic divides (Foucault, 1966 of the superheroic cartoon literature. This paper is aimed at offering a sociological view on a whole genre, made up of pure visual grammar and accounted as being particularly suitable for the representation of the implicit tensions of contemporary societies (Di Nocera, 2000. The paper offers genealogic systematizing and discussion of the implications inherent to Watchmen’s, mature and conscious production. Starting from the title, Watchmen (Moore, 1986 stands as a deliberate investigation of the archetype on which the whole genre rests. In the end, in more and more complex systems and societies, “who controls the controllers?”

  3. PVT roadmap. A European guide for the development and market introduction of PVT technology

    International Nuclear Information System (INIS)

    The aim of the roadmap is to identify promising markets for PVT (PhotoVoltaic Thermal) technology , and to identify the economical, policy, legislative and technical bottlenecks. In addition, the roadmap wants to inform the parties in the market on PVT. It thereby targets a broad range of professionals, including policy makers, solar manufacturers, installers and researchers. This work has been carried out within the PVT forum project, which is part of the EU-supported project PV-Catapult. The aim of PVT Forum is to lay the foundations for a large-scale introduction of PVT technology in Europe by means of this roadmap. In order to construct the roadmap, a two-step approach was taken. As a first step, PVT experts, PV and solar thermal industries and other stakeholders were brought together in two workshops, connected to the PVSEC 2004 in Paris and the Eurosun conference 2004 in Freiburg, to identify drivers and barriers for PVT. The results of these two workshops, that were presented in two workshop reports, were used as input for the roadmap presented here. As a second step, the PVT roadmap was written, formulating the necessary actions that should be taken on short, medium and long term in order to enlarge the market for PVT products. The chapters of the roadmap are written and reviewed by the various participants in PVT Forum. These participants have been selected for this project on the basis of their contribution to PVT development over the last years

  4. Electric field responsive origami structures using electrostriction-based active materials

    Science.gov (United States)

    Ahmed, Saad; Arrojado, Erika; Sigamani, Nirmal; Ounaies, Zoubeida

    2015-04-01

    The objective of origami engineering is to combine origami principles with advanced materials to yield active origami shapes, which fold and unfold in response to external stimuli. We are investigating the use of P(VDF-TrFE-CTFE), a relaxor ferroelectric terpolymer, to realize origami-inspired folding and unfolding of structures and to actuate so-called action origami structures. To accomplish these two objectives, we have explored different approaches to the P(VDF-TrFECTFE) polymer actuator construction, ranging from unimorph to multilayered stacks. Electromechanical characterization of the terpolymer-based actuators is conducted with a focus on free strain, force-displacement and blocked force. Moreover dynamic thickness strains of P(VDF-TrFE-CTFE) terpolymer at different frequencies ranging from 0.1Hz to 10Hz is also measured. Quantifying the performance of terpolymer-based actuators is important to the design of action origami structures. Following these studies, action origami prototypes based on catapult, flapping butterfly wings and barking fox are actuated and characterization of these prototypes are conducted by studying impact of various parameters such as electric field magnitude and frequency, number of active layers, and actuator dimensions.

  5. An examination of amphibian sensitivity to environmental contaminants: are amphibians poor canaries?

    Science.gov (United States)

    Kerby, Jacob L; Richards-Hrdlicka, Kathryn L; Storfer, Andrew; Skelly, David K

    2010-01-01

    Nearly two decades ago, the global biodiversity crisis was catapulted to the front pages of newspapers with the recognition of worldwide amphibian declines. Amphibians earned their appellation, 'canaries in a coal mine', because of apparent high sensitivity to human-mediated environmental change. The most frequently cited causes for high susceptibility include permeable skin, a dual aquatic-terrestrial life cycle and a relatively rudimentary immune system. While some researchers have questioned the basis for the canary assertion, there has been no systematic evaluation of amphibian sensitivity to environmental challenges relative to other taxa. Here, we apply a database representing thousands of toxicity tests to compare the responses of amphibians relative to that of other taxonomic groups. The use of standardized methods combined with large numbers of identical challenges enables a particularly powerful test of relative effect size. Overall, we found that amphibians only exhibit moderate relative responses to water-borne toxins. Our findings imply that, as far as chemical contaminants are concerned, amphibians are not particularly sensitive and might more aptly be described as 'miners in a coal mine'. To the extent that amphibian declines have been mediated by chemical contaminants, our findings suggest that population losses and extinctions may have already occurred in a variety of taxa much more sensitive than amphibians.

  6. Al-Qaeda in the Lands of the Islamic Maghreb

    Directory of Open Access Journals (Sweden)

    Gregory A. Smith

    2009-01-01

    Full Text Available This paper is organized into four chapters that focus on the terrorist group Al Qaeda in the Lands of the Islamic Maghreb (AQIM. The four chapters examine different facets of the collective environment that have allowed AQIM to succeed and even thrive at times. The first chapter begins with Algeria’s war of independence with the French. The second chapter focuses on the nomadic Tuareg people. It seeks to show how the Tuaregs were deprived by French occupiers and how European colonization cost the Tuaregs access to vital trade routes used for centuries. The third chapter will very briefly examine Algeria’s civil war and the emergence of modern terrorist groups. The fourth chapter will discuss the post-9/11 world in terms of “shaping operations” for the Global War on Terrorism (GWOT and how this caused an evolution in terrorism as a reaction to actual or perceived American hegemonic ambitions.This paper is not a compendium of every event or in any way a complete history of the region. It is intended to reinforce the author’s notion of outlying antecedents that normally coalesce around a central issue and how the addition of a political agenda can lead these antecedents toward a fusion point. When the fusion point is met, ethno-nationalist ambitions are catapulted down the road of terrorism and the fundamental message is lost in the debris of another attack. Such is the story of AQIM…

  7. Antibody labelling of resilin in energy stores for jumping in plant sucking insects.

    Directory of Open Access Journals (Sweden)

    Malcolm Burrows

    Full Text Available The rubbery protein resilin appears to form an integral part of the energy storage structures that enable many insects to jump by using a catapult mechanism. In plant sucking bugs that jump (Hemiptera, Auchenorrhyncha, the energy generated by the slow contractions of huge thoracic jumping muscles is stored by bending composite bow-shaped parts of the internal thoracic skeleton. Sudden recoil of these bows powers the rapid and simultaneous movements of both hind legs that in turn propel a jump. Until now, identification of resilin at these storage sites has depended exclusively upon characteristics that may not be specific: its fluorescence when illuminated with specific wavelengths of ultraviolet (UV light and extinction of that fluorescence at low pH. To consolidate identification we have labelled the cuticular structures involved with an antibody raised against a product of the Drosophila CG15920 gene. This encodes pro-resilin, the first exon of which was expressed in E. coli and used to raise the antibody. We show that in frozen sections from two species, the antibody labels precisely those parts of the metathoracic energy stores that fluoresce under UV illumination. The presence of resilin in these insects is thus now further supported by a molecular criterion that is immunohistochemically specific.

  8. Ultra High Energy Electrons Powered by Pulsar Rotation

    CERN Document Server

    Mahajan, Swadesh; Osmanov, Zaza; Chkheidze, Nino

    2013-01-01

    A new mechanism of particle acceleration to ultra high energies, driven by the rotational slow down of a pulsar (Crab pulsar, for example), is explored. The rotation, through the time dependent centrifugal force, can very efficiently excite unstable Langmuir waves in the e-p plasma of the star magnetosphere via a parametric process. These waves, then, Landau damp on electrons accelerating them in the process. The net transfer of energy is optimal when the wave growth and the Landau damping times are comparable and are both very short compared to the star rotation time. We show, by detailed calculations, that these are precisely the conditions for the parameters of the Crab pulsar. This highly efficient route for energy transfer allows the electrons in the primary beam to be catapulted to multiple TeV ($\\sim 100$ TeV) and even PeV energy domain. It is expected that the proposed mechanism may, partially, unravel the puzzle of the origin of ultra high energy cosmic ray electrons.

  9. 1999 Gordon Research Conference on Mammalian DNA Repair. Final Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-02-12

    This Conference will examine DNA repair as the key component in genomic surveillance that is so crucial to the overall integrity and function of mammalian cells. Recent discoveries have catapulted the field of DNA repair into a pivotal position for fundamental investigations into oncology, aging, environmental health, and developmental biology. We hope to highlight the most promising and exciting avenues of research in robust discussions at this conference. This Mammalian DNA Repair Gordon Conference differs from the past conferences in this series, in which the programs were broader in scope, with respect to topics and biological systems covered. A conference sponsored by the Genetics Society in April 1998 emphasized recombinational mechanisms for double-strand break repair and the role of mismatch repair deficiency in colorectal cancer. These topics will therefore receive somewhat less emphasis in the upcoming Conference. In view of the recent mechanistic advances in mammalian DNA repair, an upcoming comprehensive DNA repair meeting next autumn at Hilton Head; and the limited enrollment for Gordon Conferences we have decided to focus session-by-session on particular areas of controversy and/or new developments specifically in mammalian systems. Thus, the principal presentations will draw upon results from other cellular systems only to the extent that they impact our understanding of mammalian DNA repair.

  10. The buzz on buzz.

    Science.gov (United States)

    Dye, R

    2000-01-01

    Word-of-mouth promotion has become an increasingly potent force, capable of catapulting products from obscurity into runaway commercial successes. Harry Potter, collapsible scooters, the Chrysler PT Cruiser, and The Blair Witch Project are all recent examples of the considerable power of buzz. Yet many top executives and marketing managers are misinformed about the phenomenon and remain enslaved to some common myths. In her article, author Renée Dye explores the truth behind these myths. Myth 1: Only outrageous or edgy products are buzz-worthy. That's simply not true. The most unlikely products, like prescription drugs, can generate tremendous buzz. Myth 2: Buzz just happens. Not so, says Dye. Buzz is increasingly the result of shrewd marketing tactics in which companies seed a vanguard group, ration supplies, use celebrity endorsements, leverage the power of lists, and initiate grassroots marketing. Myth 3: The best buzz-starters are your best customers. Often, a counterculture has a greater ability to start buzz. Myth 4: To profit from buzz, you must act first and fast. In fact, copycat companies can reap substantial profits if they know when and when not to jump in. Myth 5: The media and advertising are needed to create buzz. When used either too early or too much, the media and advertising can squelch buzz before it ignites. As globalization and brand proliferation continue, writes Dye, buzz may come to dominate the shaping of markets. Indeed, companies that are unable to control buzz may soon find the phenomenon controlling them.

  11. International exploration by independent

    International Nuclear Information System (INIS)

    Recent industry trends indicate that the smaller U.S. independents are looking at foreign exploration opportunities as one of the alternatives for growth in the new age of exploration. Foreign finding costs per barrel usually are accepted to be substantially lower than domestic costs because of the large reserve potential of international plays. To get involved in overseas exploration, however, requires the explorationist to adapt to different cultural, financial, legal, operational, and political conditions. Generally, foreign exploration proceeds at a slower pace than domestic exploration because concessions are granted by a country's government, or are explored in partnership with a national oil company. First, the explorationist must prepare a mid- to long-term strategy, tailored to the goals and the financial capabilities of the company; next, is an ongoing evaluation of quality prospects in various sedimentary basins, and careful planning and conduct of the operations. To successfully explore overseas also requires the presence of a minimum number of explorationists and engineers thoroughly familiar with the various exploratory and operational aspects of foreign work. Ideally, these team members will have had a considerable amount of on-site experience in various countries and climates. Independents best suited for foreign expansion are those who have been financially successful in domestic exploration. When properly approached, foreign exploration is well within the reach of smaller U.S. independents, and presents essentially no greater risk than domestic exploration; however, the reward can be much larger and can catapult the company into the 'big leagues.'

  12. International exploration by independents

    International Nuclear Information System (INIS)

    Recent industry trends indicate that the smaller US independents are looking at foreign exploration opportunities as one of the alternatives for growth in the new age of exploration. It is usually accepted that foreign finding costs per barrel are substantially lower than domestic because of the large reserve potential of international plays. To get involved overseas requires, however, an adaptation to different cultural, financial, legal, operational, and political conditions. Generally foreign exploration proceeds at a slower pace than domestic because concessions are granted by the government, or are explored in partnership with the national oil company. First, a mid- to long-term strategy, tailored to the goals and the financial capabilities of the company, must be prepared; it must be followed by an ongoing evaluation of quality prospects in various sedimentary basins, and a careful planning and conduct of the operations. To successfully explore overseas also requires the presence on the team of a minimum number of explorationists and engineers thoroughly familiar with the various exploratory and operational aspects of foreign work, having had a considerable amount of onsite experience in various geographical and climatic environments. Independents that are best suited for foreign expansion are those that have been financially successful domestically, and have a good discovery track record. When properly approached foreign exploration is well within the reach of smaller US independents and presents essentially no greater risk than domestic exploration; the reward, however, can be much larger and can catapult the company into the big leagues

  13. Genetic analysis of the early natural history of epithelial ovarian carcinoma.

    Directory of Open Access Journals (Sweden)

    Bhavana Pothuri

    Full Text Available BACKGROUND: The high mortality rate associated with epithelial ovarian carcinoma (EOC reflects diagnosis commonly at an advanced stage, but improved early detection is hindered by uncertainty as to the histologic origin and early natural history of this malignancy. METHODOLOGY/PRINCIPAL FINDINGS: Here we report combined molecular genetic and morphologic analyses of normal human ovarian tissues and early stage cancers, from both BRCA mutation carriers and the general population, indicating that EOCs frequently arise from dysplastic precursor lesions within epithelial inclusion cysts. In pathologically normal ovaries, molecular evidence of oncogenic stress was observed specifically within epithelial inclusion cysts. To further explore potential very early events in ovarian tumorigenesis, ovarian tissues from women not known to be at high risk for ovarian cancer were subjected to laser catapult microdissection and gene expression profiling. These studies revealed a quasi-neoplastic expression signature in benign ovarian cystic inclusion epithelium compared to surface epithelium, specifically with respect to genes affecting signal transduction, cell cycle control, and mitotic spindle formation. Consistent with this gene expression profile, a significantly higher cell proliferation index (increased cell proliferation and decreased apoptosis was observed in histopathologically normal ovarian cystic compared to surface epithelium. Furthermore, aneuploidy was frequently identified in normal ovarian cystic epithelium but not in surface epithelium. CONCLUSIONS/SIGNIFICANCE: Together, these data indicate that EOC frequently arises in ovarian cystic inclusions, is preceded by an identifiable dysplastic precursor lesion, and that increased cell proliferation, decreased apoptosis, and aneuploidy are likely to represent very early aberrations in ovarian tumorigenesis.

  14. Obstacle avoidance and path planning for carrier aircraft launching

    Directory of Open Access Journals (Sweden)

    Wu Yu

    2015-06-01

    Full Text Available Launching safety and efficiency are important indexes to measure the fighting capacity of carrier. The study on path planning for taxi of carrier aircraft launching under actual deck environment is of great significance. In actual deck scheduling, manual command is applied to taxi of carrier aircraft, which has negative effects on the safety of staff and carrier aircraft launching. In consideration of both the safety and efficiency of carrier aircraft launching, the key elements of the problem are abstracted based on the analysis of deck environment, carrier aircraft maneuver performance and task requirements. According to the problem description, the mathematical model is established including various constraints. The carrier aircraft and the obstacles are reasonably simplified as circle and polygons respectively. What’s more, the proposed collision detection model reduces the calculations. Aimed at the features of model, the theory of model predictive control (MPC is applied to the path search. Then a dynamic weight heuristic function is designed and a dynamic multistep optimization algorithm is proposed. Taking the Nimitz-class aircraft carrier as an example, the paths from parking place to catapult are planned, which indicate the rationality of the model and the effectiveness of the algorithm by comparing the planning results under different simulation environments. The main contribution of research is the establishment of obstacle avoidance and path planning model. In addition, it provides the solution of model and technological foundations for comprehensive command and real-time decision-making of the carrier aircraft.

  15. An On-Line Algorithm for Measuring the Translational and Rotational Velocities of a Table Tennis Ball

    Science.gov (United States)

    Liu, Chunfang; Hayakawa, Yoshikazu; Nakashima, Akira

    This paper proposes an on-line method for estimating both translational and rotational velocities of a table tennis ball by using only a few consecutive frames of image data which are sensed by two high speed cameras. In order to estimate the translational velocity, three-dimensional (3D) position of the ball's center at each instant of camera frame is obtained, where the on-line method of reconstructing the 3D position from the two-dimensional (2D) image data of two cameras is proposed without the pattern matching process. The proposed method of estimating the rotational velocity belongs to the image registration methods, where in order to avoid the pattern matching process too, a rotation model of the ball is used to make an estimated image data from an image data sensed at the previous instant of camera frame and then the estimated image data are compared with the image data sensed at the next instant of camera frame to obtain the most plausible rotational velocity by using the least square and the conjugate gradient method. The effectiveness of the proposed method is shown by some experimental results in the case of a ball rotated by a rotation machine as well as in the case of a flying ball shot from a catapult machine.

  16. The history of the oldest self-sustaining laboratory animal: 150 years of axolotl research.

    Science.gov (United States)

    Reiß, Christian; Olsson, Lennart; Hoßfeld, Uwe

    2015-07-01

    Today the Mexican axolotl is critically endangered in its natural habitat in lakes around Mexico City, but thrives in research laboratories around the world, where it is used for research on development, regeneration, and evolution. Here, we concentrate on the early history of the axolotl as a laboratory animal to celebrate that the first living axolotls arrived in Paris in 1864, 150 years ago. Maybe surprisingly, at first the axolotl was distributed across Europe without being tied to specific research questions, and amateurs engaged in acclimatization and aquarium movements played an important role for the rapid proliferation of the axolotl across the continent. But the aquarium also became an important part of the newly established laboratory, where more and more biological and medical research now took place. Early scientific interest focused on the anatomical peculiarities of the axolotl, its rare metamorphosis, and whether it was a larva or an adult. Later, axolotl data was used to argue both for (by August Weismann and others) and against (by e.g., Albert von Kölliker) Darwinism, and the axolotl even had a brief history as a laboratory animal used in a failed attempt to prove Lysenkoism in Jena, Germany. Nowadays, technical developments such as transgenic lines, and the very strong interest in stem cell and regeneration research has again catapulted the axolotl into becoming an important laboratory animal.

  17. Sporangium Exposure and Spore Release in the Peruvian Maidenhair Fern (Adiantum peruvianum, Pteridaceae.

    Directory of Open Access Journals (Sweden)

    Simon Poppinga

    Full Text Available We investigated the different processes involved in spore liberation in the polypod fern Adiantum peruvianum (Pteridaceae. Sporangia are being produced on the undersides of so-called false indusia, which are situated at the abaxial surface of the pinnule margins, and become exposed by a desiccation-induced movement of these pinnule flaps. The complex folding kinematics and functional morphology of false indusia are being described, and we discuss scenarios of movement initiation and passive hydraulic actuation of these structures. High-speed cinematography allowed for analyses of fast sporangium motion and for tracking ejected spores. Separation and liberation of spores from the sporangia are induced by relaxation of the annulus (the 'throwing arm' of the sporangium catapult and conservation of momentum generated during this process, which leads to sporangium bouncing. The ultra-lightweight spores travel through air with a maximum velocity of ~5 m s(-1, and a launch acceleration of ~6300 g is measured. In some cases, the whole sporangium, or parts of it, together with contained spores break away from the false indusium and are shed as a whole. Also, spores can stick together and form spore clumps. Both findings are discussed in the context of wind dispersal.

  18. Sporangium Exposure and Spore Release in the Peruvian Maidenhair Fern (Adiantum peruvianum, Pteridaceae).

    Science.gov (United States)

    Poppinga, Simon; Haushahn, Tobias; Warnke, Markus; Masselter, Tom; Speck, Thomas

    2015-01-01

    We investigated the different processes involved in spore liberation in the polypod fern Adiantum peruvianum (Pteridaceae). Sporangia are being produced on the undersides of so-called false indusia, which are situated at the abaxial surface of the pinnule margins, and become exposed by a desiccation-induced movement of these pinnule flaps. The complex folding kinematics and functional morphology of false indusia are being described, and we discuss scenarios of movement initiation and passive hydraulic actuation of these structures. High-speed cinematography allowed for analyses of fast sporangium motion and for tracking ejected spores. Separation and liberation of spores from the sporangia are induced by relaxation of the annulus (the 'throwing arm' of the sporangium catapult) and conservation of momentum generated during this process, which leads to sporangium bouncing. The ultra-lightweight spores travel through air with a maximum velocity of ~5 m s(-1), and a launch acceleration of ~6300 g is measured. In some cases, the whole sporangium, or parts of it, together with contained spores break away from the false indusium and are shed as a whole. Also, spores can stick together and form spore clumps. Both findings are discussed in the context of wind dispersal. PMID:26444002

  19. Pharmacodynamics and Systems Pharmacology Approaches to Repurposing Drugs in the Wake of Global Health Burden.

    Science.gov (United States)

    Bai, Jane P F

    2016-10-01

    There are emergent needs for cost-effective treatment worldwide, for which repurposing to develop a drug with existing marketing approval of disease(s) for new disease(s) is a valid option. Although strategic mining of electronic health records has produced real-world evidences to inform drug repurposing, using omics data (drug and disease), knowledge base of protein interactions, and database of transcription factors have been explored. Structured integration of all the existing data under the framework of drug repurposing will facilitate decision making. The ability to foresee the need to integrate new data types produced by emergent technologies and to enable data connectivity in the context of human biology and targeted diseases, as well as to use the existing crucial quality data of all approved drugs will catapult the number of drugs being successfully repurposed. However, translational pharmacodynamics databases for modeling information across human biology in the context of host factors are lacking and are critically needed for drug repurposing to improve global public health, especially for the efforts to combat neglected tropic diseases as well as emergent infectious diseases such as Zika or Ebola virus.

  20. Short Duration Reduced Gravity Drop Tower Design and Development

    Science.gov (United States)

    Osborne, B.; Welch, C.

    The industrial and commercial development of space-related activities is intimately linked to the ability to conduct reduced gravity research. Reduced gravity experimentation is important to many diverse fields of research in the understanding of fundamental and applied aspects of physical phenomena. Both terrestrial and extra-terrestrial experimental facilities are currently available to allow researchers access to reduced gravity environments. This paper discusses two drop tower designs, a 2.0 second facility built in Australia and a proposed 2.2 second facility in the United Kingdom. Both drop towers utilise a drag shield for isolating the falling experiment from the drag forces of the air during the test. The design and development of The University of Queensland's (Australia) 2.0 second drop tower, including its specifications and operational procedures is discussed first. Sensitive aspects of the design process are examined. Future plans are then presented for a new short duration (2.2 sec) ground-based reduced gravity drop tower. The new drop tower has been designed for Kingston University (United Kingdom) to support teaching and research in the field of reduced gravity physics. The design has been informed by the previous UQ drop tower design process and utilises a catapult mechanism to increase test time and also incorporates features to allow participants for a variety of backgrounds (from high school students through to university researchers) to learn and experiment in reduced gravity. Operational performance expectations for this new facility are also discussed.

  1. Human obesity and insulin resistance: lessons from experiments of nature.

    Science.gov (United States)

    O'Rahilly, Stephen

    2007-01-01

    The past decade or so has seen the adipocyte catapulted from a position of relative obscurity onto the centre stage of biomedical science. Having long been viewed largely as a passive storage depot for energy in times of plenty and a fuel reservoir called upon in times of need, the discovery that the adipocyte is an active participant in the control mechanisms for both energy balance and intermediary metabolism represents one of the most stunning paradigm shifts in modern mammalian biology. The normal control of energy homeostasis is now known to be highly dependent on the adipocyte-secreted hormone, leptin. Defects in the leptin signalling pathway, both inherited and acquired, are now known to contribute to the important clinical problem of obesity. Dysfunction of adipocytes, in both obesity and lipodystrophies, is now considered to be critically involved in the pathogenesis of insulin resistance, the metabolic syndrome and type 2 diabetes. The range of metabolites, steroids and bioactive peptides now known to be actively produced by adipocytes and influencing organs as diverse as brain, muscle, liver and pancreatic islet has increased dramatically. Our understanding of how these are co-ordinated to regulate normal metabolism and are dysregulated in metabolic disease is still in its infancy. However what is clear is that the adipocyte, until recently the 'Cinderella Cell' of metabolism, has rapidly become the 'Belle of the Ball'. PMID:18269171

  2. Oppenheimer the tragic intellect

    CERN Document Server

    Thorpe, Charles

    2008-01-01

    At a time when the Manhattan Project was synonymous with large-scale science, physicist J. Robert Oppenheimer (1904-67) represented the new sociocultural power of the American intellectual. Catapulted to fame as director of the Los Alamos atomic weapons laboratory, Oppenheimer occupied a key position in the compact between science and the state that developed out of World War II. By tracing the making-and unmaking-of Oppenheimer's wartime and postwar scientific identity, Charles Thorpe illustrates the struggles over the role of the scientist in relation to nuclear weapons, the state, and culture.  A stylish intellectual biography, Oppenheimer maps out changes in the roles of scientists and intellectuals in twentieth-century America, ultimately revealing transformations in Oppenheimer's persona that coincided with changing attitudes toward science in society.  "This is an outstandingly well-researched book, a pleasure to read and distinguished by the high quality of its observations and judgments. It will b...

  3. A novel classification of planar four-bar linkages and its application to the mechanical analysis of animal systems.

    Science.gov (United States)

    Muller, M

    1996-05-29

    A novel classification of planar four-bar linkages is presented based on the systematical variation of one, two or three bar lengths and studying the transmission properties (input-output curves) of the linkages. This classification is better suited to the study of biological systems than the classical Grashof-classification used in engineering as it considers the change of structural elements, in evolution for example, instead of evaluating the possibilities for the rotation of a particular bar. The mechanical features of a wide range of planar linkages in vertebrates, described by various authors, have been included in this classification. Examples are: skull-levation and jaw-protrusion mechanisms in fishes, reptiles and birds, the coral crushing apparatus of parrotfishes, and catapult-mechanisms in feeding pipefishes. Four-bar replacement mechanisms, e.g., crank-slider mechanisms in feeding systems of fishes and cam-mechanisms in mammalian limb-joints, and more complex linkages than four-bar ones, e.g., six-bar linkages and interconnected four-bar linkages in fish feeding mechanisms are also discussed. In this way, an overview is obtained of the applicability of planar linkage theory in animal mechanics to mechanical functioning and the effect of possible variations of bar lengths and working ranges in evolution. Four-bar system analysis often provides a rigorous method of simplifying the study of complex biological mechanisms. The acceptable width-range of necessary and undesired hysteresis ('play') in biological linkages is also discussed. PMID:8927640

  4. A miniaturized, high flux BEC source for precision atom interferometry

    Science.gov (United States)

    Herr, Waldemar; Rudolph, Jan; Popp, Manuel; Rasel, Ernst; Quantus Collaboration

    2013-05-01

    Atom chips have proven to be excellent sources for the fast production of ultra-cold gases due to their outstanding performance in evaporative cooling. However, the total number of atoms has previously been limited by the small volume of their magnetic traps. To overcome this restriction, we have developed a novel loading scheme that allows us to produce Bose-Einstein condensates of a few 105 87Rb atoms every two seconds. The apparatus is designed to be operated in microgravity at the drop tower in Bremen, where even higher numbers of atoms can be achieved in the absence of any gravitational sag. Using the drop tower's catapult mode, our setup will perform atom interferometry during nine seconds in free fall. Thus, the fast loading scheme allows for interferometer sequences of up to seven seconds - interrogation times which are inaccessible for ground based devices. The QUANTUS project is supported by the German Space Agency DLR with funds provided by the Federal Ministry of Economics and Technology (BMWi) under grant number DLR 50WM1131. Leibniz Universitaet Hannover, Universitaet Bremen, HU Berlin, Universitaet Hamburg, Universitaet Ulm, TU Darmstadt, MPQ-Garching.

  5. ESA Parabolic Flight, Drop Tower and Centrifuge Opportunities for University Students

    Science.gov (United States)

    Callens, Natacha; Ventura-Traveset, Javier; Zornoza Garcia-Andrade, Eduardo; Gomez-Calero, Carlos; van Loon, Jack J. W. A.; Pletser, Vladimir; Kufner, Ewald; Krause, Jutta; Lindner, Robert; Gai, Frederic; Eigenbrod, Christian

    The European Space Agency (ESA) Education Office was established in 1998 with the purpose of motivating young people to study science, engineering and technology subjects and to ensure a qualified workforce for ESA and the European space sector in the future. To this end the ESA Education Office is supporting several hands-on activities including small student satellites and student experiments on sounding rockets, high altitude balloons as well as microgravity and hypergravity platforms. This paper is intended to introduce three new ESA Education Office hands-on activities called "Fly Your Thesis!", "Drop Your Thesis!" and "Spin Your Thesis!". These activities give re-spectively access to aircraft parabolic flight, drop tower and centrifuge campaigns to European students. These educational programmes offer university students the unique opportunity to design, build, and eventually perform, in microgravity or hypergravity, a scientific or techno-logical experiment which is linked to their syllabus. During the "Fly Your Thesis!" campaigns, the students accompany their experiments onboard the A300 Zero-G aircraft, operated by the company Novespace, based in Bordeaux, France, for a series of three flights of 30 parabolas each, with each parabola providing about 20s of microgravity [1]. "Drop Your Thesis!" campaigns are held in the ZARM Drop Tower, in Bremen, Germany. The installation delivers 4.74s of microgravity in dropping mode and 9.3s in the catapulting mode [2]. Research topics such as fluid physics, fundamental physics, combustion, biology, material sciences, heat transfer, astrophysics, chemistry or biochemistry can greatly benefit from using microgravity platforms. "Spin Your Thesis!" campaigns take place in the Large Diameter Centrifuge (LDC) facility, at ESTEC, Noordwijk, in the Netherlands. This facility offers an acceleration from 1 to 20 times Earth's gravity [3]. The use of hypergravity allows completing the scientific picture of how gravity has an

  6. William Herschel during the 1780-1810 era: A natural historian studies "maturation" of stars over immeasurable time

    Science.gov (United States)

    Sullivan, Woody

    2015-01-01

    (A) William Herschel (1738-1822) considered himself a natural historian, different only from the usual natural historians in that his focus was on stars and nebulae rather than plants, animals, and minerals. In this regard, he developed ideas concerning changes over very long times, inferred from his catalogues of 2500 star clusters and nebulae. By assuming that all the observed types of star clusters and morphologies of nebulae represented different stages in the formation of stars and clusters under the action of gravity, Herschel argued for a sequence of "maturation," or evolution as we would call it. He could put no definite time scale on these dynamic processes, but inspired by contemporary geologists such as James Hutton and John Michell (yes, he was a geologist, too!), he felt that the time scales must be very long. In further support, he photometrically estimated that the very faintest stars that he could see in his giant 40-ft telescope were about two million light-years distant. Herschel's findings on the structure and age of the Milky Way system, his "construction of the heavens," were also influenced by geological notions of the formation and subsequent warping of strata over long times, and the geologists' attempts to uncover the interior and distant past of the Earth. (B) Herschel was a very successful professional musician for two decades, primarily in the fashionable resort city of Bath, England. And then he discovered Uranus in 1781 at age 43, an event that catapulted him into celebrity and allowed him immediately to transform himself into a full-time astronomer. He composed over twenty symphonies, many concertos, and a large number of organ and choral works. During this session, a chorus of University of Washington students will present a short concert featuring Herschel's most popular composition, a novelty number called "The Eccho Catch," as well as contemporary pieces with astronomical themes by other composers.

  7. The Expanding Realm of Endovascular Neurosurgery: Flow Diversion for Cerebral Aneurysm Management

    Science.gov (United States)

    Krishna, Chandan; Sonig, Ashish; Natarajan, Sabareesh K.; Siddiqui, Adnan H.

    2014-01-01

    The worldwide prevalence of intracranial aneurysms is estimated to be between 5% and 10%, with some demographic variance. Subarachnoid hemorrhage secondary to ruptured intracranial aneurysm results in devastating neurological outcomes, leaving the majority of victims dead or disabled. Surgical clipping of intracranial aneurysms remained the definitive mode of treatment until Guglielmi detachable coils were introduced in the 1990s. This revolutionary innovation led to the recognition of neurointervention/neuroendovascular surgery as a bona fide option for intracranial aneurysms. Constant evolution of endovascular devices and techniques supported by several prospective randomized trials has catapulted the endovascular treatment of intracranial aneurysms to its current status as the preferred treatment modality for most ruptured and unruptured intracranial aneurysms. We are slowly transitioning from the era of coils to the era of flow diverters. Flow-diversion technology and techniques have revolutionized the treatment of wide-necked, giant, and fusiform aneurysms, where the results of microsurgery or conventional neuroendovascular strategies have traditionally been dismal. Although the Pipeline™ Embolization Device (ev3-Covidien, Irvine, CA) is the only flow-diversion device approved by the Food and Drug Administration for use in the United States, others are commercially available in Europe and South America, including the Silk (Balt Extrusion, Montmorency, France), Flow-Redirection Endoluminal Device (FRED; MicroVention, Tustin, CA), Surpass (Stryker, Kalamazoo, MI), and p64 (Phenox, Bochum, Germany). Improvements in technology and operator experience and the encouraging results of clinical trials have led to broader acceptance for the use of these devices in cerebral aneurysm management. Continued innovation and refinement of endovascular devices and techniques will inevitably improve technical success rates, reduce procedure-related complications, and broaden

  8. Tests Results of the Electrostatic Accelerometer Flight Models for Gravity Recovery and Climate Experiment Follow-On Mission (GRACE FO)

    Science.gov (United States)

    Perrot, E.; Boulanger, D.; Christophe, B.; Foulon, B.; Lebat, V.; Huynh, P. A.; Liorzou, F.

    2015-12-01

    The GRACE FO mission, led by the JPL (Jet Propulsion Laboratory), is an Earth-orbiting gravity mission, continuation of the GRACE mission, which will produce an accurate model of the Earth's gravity field variation providing global climatic data during five years at least. The mission involves two satellites in a loosely controlled tandem formation, with a micro-wave link measuring the inter-satellites distance variation. Earth's mass distribution non-uniformities cause variations of the inter-satellite distance. This variation is measured to recover gravity, after subtracting the non-gravitational contributors, as the residual drag. ONERA (the French Aerospace Lab) is developing, manufacturing and testing electrostatic accelerometers measuring this residual drag applied on the satellites. The accelerometer is composed of two main parts: the Sensor Unit (including the Sensor Unit Mechanics - SUM - and the Front-End Electronic Unit - FEEU) and the Interface Control Unit - ICU. In the Accelerometer Core, located in the Sensor Unit Mechanics, the proof mass is levitated and maintained at the center of an electrode cage by electrostatic forces. Thus, any drag acceleration applied on the satellite involves a variation on the servo-controlled electrostatic suspension of the mass. The voltage on the electrodes providing this electrostatic force is the output measurement of the accelerometer. The impact of the accelerometer defaults (geometry, electronic and parasitic forces) leads to bias, misalignment and scale factor error, non-linearity and noise. Some of these accelerometer defaults are characterized by tests with micro-gravity pendulum bench on ground and with drops in ZARM catapult. The Critical Design Review was achieved successfully on September 2014. The Engineering Model (EM) was integrated and tested successfully, with ground levitation, drops, Electromagnetic Compatibility and thermal vacuum. The integration of the two Flight Models was done on July 2015. The

  9. Status of Electrostatic Accelerometer Development for Gravity Recovery and Climate Experiment Follow-On Mission (GRACE FO)

    Science.gov (United States)

    Perrot, Eddy; Boulanger, Damien; Christophe, Bruno; Foulon, Bernard; Liorzou, Françoise; Lebat, Vincent; Huynh, Phuong-Anh

    2015-04-01

    The GRACE FO mission, led by the JPL (Jet Propulsion Laboratory), is an Earth-orbiting gravity mission, continuation of the GRACE mission, which will produce an accurate model of the Earth's gravity field variation providing global climatic data during five years at least. The mission involves two satellites in a loosely controlled tandem formation, with a micro-wave link measuring the inter-satellites distance variation. Earth's mass distribution non-uniformities cause variations of the inter-satellite distance. This variation is measured to recover gravity, after subtracting the non-gravitational contributors, as the residual drag. ONERA (the French Aerospace Lab) is developing, manufacturing and testing electrostatic accelerometers measuring this residual drag applied on the satellites. The accelerometer is composed of two main parts: the Sensor Unit (including the Sensor Unit Mechanics - SUM - and the Front-End Electronic Unit - FEEU) and the Interface Control Unit - ICU. In the Accelerometer Core, located in the Sensor Unit Mechanics, the proof mass is levitated and maintained at the center of an electrode cage by electrostatic forces. Thus, any drag acceleration applied on the satellite involves a variation on the servo-controlled electrostatic suspension of the mass. The voltage on the electrodes providing this electrostatic force is the measurement output of the accelerometer. The impact of the accelerometer defaults (geometry, electronic and parasitic forces) leads to bias, misalignment and scale factor error, non-linearity and noise. Some of these accelerometer defaults are characterized by tests with micro-gravity pendulum bench on ground and with drops in ZARM catapult. The Critical Design Review was achieved successfully on September 2014. The Engineering Model (EM) was integrated and tested successfully, with ground levitation, drops, Electromagnetic Compatibility and thermal vacuum. The integration of the first Flight Model has begun on December 2014

  10. Revictimización un fenómeno invisibilizado en las instituciones Revictimization an invisiblelized phenomena in institutions

    Directory of Open Access Journals (Sweden)

    Berenice Smith Bonilla

    2007-03-01

    Full Text Available El presente trabajo de investigación sobre la revictimiación institucional pone de manifiesto la existencia de dicho fenómeno dentro del sistema judicial. Se analizan las causas de esta situación la cual aparenta no tener la debida cobertura del sistema ni la de los propios funcionarios que laboran en tal situación. Se hace una exposición de motivos que explica el fenómeno que incluye las políticas existentes, las estrategias de capacitación, difusión y consistencia. Además se estudia la existencia de la Oficina de Atención a la Víctima del Delito desde su iniciativa, la cual catapulta la figura de la víctima a un lugar hasta entonces negado, sin que su actuar trascienda al ámbito requerido por razones que se analizan. En las conclusiones se brindan recomendaciones pertinentes para quienes están sufriendo como victimas por su labor.This investigation about institutional revictimization demonstrates the existence of this phenomenon within the judicial system. The causes of this situation are analyzed, that seems not to have the appropriate coverage from the system nor from the employees of the institutions. An exposition of the different motives is done to explain the phenomenon that includes current policies, capacitating strategies, diffusion and consistency. Also the existence of the Attention to Victim of Crime Office is studied from its initiative, which catapults the victim figure to a previously denied place. As conclusions, some recommendations are brought for those who are suffering as victims.

  11. ArcticDEM; A Publically Available, High Resolution Elevation Model of the Arctic

    Science.gov (United States)

    Morin, Paul; Porter, Claire; Cloutier, Michael; Howat, Ian; Noh, Myoung-Jong; Willis, Michael; Bates, Brian; Willamson, Cathleen; Peterman, Kennith

    2016-04-01

    A Digital Elevation Model (DEM) of the Arctic is needed for a large number of reasons, including: measuring and understanding rapid, ongoing changes to the Arctic landscape resulting from climate change and human use and mitigation and adaptation planning for Arctic communities. The topography of the Arctic is more poorly mapped than most other regions of Earth due to logistical costs and the limits of satellite missions with low-latitude inclinations. A convergence of civilian, high-quality sub-meter stereo imagery; petascale computing and open source photogrammetry software has made it possible to produce a complete, very high resolution (2 to 8-meter posting), elevation model of the Arctic. A partnership between the US National Geospatial-intelligence Agency and a team led by the US National Science Foundation funded Polar Geospatial Center is using stereo imagery from DigitalGlobe's Worldview-1, 2 and 3 satellites and the Ohio State University's Surface Extraction with TIN-based Search-space Minimization (SETSM) software running on the University of Illinois's Blue Water supercomputer to address this challenge. The final product will be a seemless, 2-m posting digital surface model mosaic of the entire Arctic above 60 North including all of Alaska, Greenland and Kamchatka. We will also make available the more than 300,000 individual time-stamped DSM strip pairs that were used to assemble the mosaic. The Arctic DEM will have a vertical precision of better than 0.5m and can be used to examine changes in land surfaces such as those caused by permafrost degradation or the evolution of arctic rivers and floodplains. The data set can also be used to highlight changing geomorphology due to Earth surface mass transport processes occurring in active volcanic and glacial environments. When complete the ArcticDEM will catapult the Arctic from the worst to among the best mapped regions on Earth.

  12. Resilin and chitinous cuticle form a composite structure for energy storage in jumping by froghopper insects

    Directory of Open Access Journals (Sweden)

    Shaw Stephen R

    2008-09-01

    Full Text Available Abstract Background Many insects jump by storing and releasing energy in elastic structures within their bodies. This allows them to release large amounts of energy in a very short time to jump at very high speeds. The fastest of the insect jumpers, the froghopper, uses a catapult-like elastic mechanism to achieve their jumping prowess in which energy, generated by the slow contraction of muscles, is released suddenly to power rapid and synchronous movements of the hind legs. How is this energy stored? Results The hind coxae of the froghopper are linked to the hinges of the ipsilateral hind wings by pleural arches, complex bow-shaped internal skeletal structures. They are built of chitinous cuticle and the rubber-like protein, resilin, which fluoresces bright blue when illuminated with ultra-violet light. The ventral and posterior end of this fluorescent region forms the thoracic part of the pivot with a hind coxa. No other structures in the thorax or hind legs show this blue fluorescence and it is not found in larvae which do not jump. Stimulating one trochanteral depressor muscle in a pattern that simulates its normal action, results in a distortion and forward movement of the posterior part of a pleural arch by 40 μm, but in natural jumping, the movement is at least 100 μm. Conclusion Calculations showed that the resilin itself could only store 1% to 2% of the energy required for jumping. The stiffer cuticular parts of the pleural arches could, however, easily meet all the energy storage needs. The composite structure therefore, combines the stiffness of the chitinous cuticle with the elasticity of resilin. Muscle contractions bend the chitinous cuticle with little deformation and therefore, store the energy needed for jumping, while the resilin rapidly returns its stored energy and thus restores the body to its original shape after a jump and allows repeated jumping.

  13. Development and deposition of resilin in energy stores for locust jumping.

    Science.gov (United States)

    Burrows, Malcolm

    2016-08-15

    Locusts jump by using a catapult mechanism in which energy produced by slow contractions of the extensor tibiae muscles of the hind legs is stored in distortions of the exoskeleton, most notably (1) the two semi-lunar processes at each knee joint and (2) the tendons of the extensor muscles themselves. The energy is then suddenly released from these stores to power the rapid, propulsive movements of the hind legs. The reliance on the mechanical storage of energy is likely to impact on jumping because growth occurs by a series of five moults, at each of which the exoskeleton is replaced by a new one. All developmental stages (instars) nevertheless jump as a means of forward locomotion, or as an escape movement. Here, I show that in each instar, resilin is added to the semi-lunar processes and to the core of the extensor tendons so that their thickness increases. As the next moult approaches, a new exoskeleton forms within the old one, with resilin already present in the new semi-lunar processes. The old exoskeleton, the tendons and their resilin are discarded at moulting. The resilin of the semi-lunar processes and tendons of the new instar is initially thin, but a similar pattern of deposition results in an increase of their thickness. In adults, resilin continues to be deposited so that at 4 weeks old the thickness in the semi-lunar processes has increased fourfold. These changes in the energy stores accompany changes in jumping ability and performance during each moulting cycle. PMID:27259374

  14. The C1q family of proteins: insights into the emerging non-traditional functions

    Directory of Open Access Journals (Sweden)

    Berhane eGhebrehiwet

    2012-04-01

    Full Text Available Research conducted over the past 20 years have helped us unravel not only the hidden structural and functional subtleties of human C1q, but also has catapulted the molecule from a mere recognition unit of the classical pathway to a well-recognized molecular sensor of damage modified self or non-self antigens. Thus, C1q is involved in a rapidly expanding list of pathological disorders—including autoimmunity, trophoblast migration, preeclampsia and cancer. The results of two recent reports are provided to underscore the critical role C1q plays in health and disease. First is the observation by Singh and colleagues showing that pregnant C1q-/- mice recapitulate the key features of human preeclampsia that correlate with increased fetal death. Treatment of the C1q-/- mice with pravastatin restored trophoblast invasiveness, placental blood flow, and angiogenic balance and, thus, prevented the onset of preeclampsia. Second is the report by Hong et al., which showed that C1q can induce apoptosis of prostate cancer cells by activating the tumor suppressor molecule WW-domain containing oxydoreductase (WWOX or WOX1 and destabilizing cell adhesion. Downregulation of C1q on the other hand enhanced prostate hyperplasia and cancer formation due to failure of WOX1 activation. Recent evidence also shows that C1q belongs to a family of structurally and functionally related TNFα-like family of proteins that may have arisen from a common ancestral gene. Therefore C1q not only shares the diverse functions with the TNF family of proteins, but also explains why C1q has retained some of its ancestral cytokine-like activities. This review is intended to highlight some of the structural and functional aspects of C1q by underscoring the growing list of its non-traditional functions.

  15. The perils of the imitation age.

    Science.gov (United States)

    Bonabeau, Eric

    2004-06-01

    Imitation exerts enormous influence over society, and business and finance in particular. And its influence has grown as the avenues by which people imitate--and are imitated--have multiplied and the process has gotten faster. Thousands of communications channels make it possible for virtually anyone in the developed world to know, almost instantaneously, what others do, think, believe, claim, or predict. More significantly, we can and do act upon such knowledge. The resulting fads and fashions, bubbles and crashes are ever more frequent, severe, and complex. The information age has cast up more than its share of paradoxes, including this one: When information is plentiful, we often use it not to make better decisions but to imitate others--and their mistakes. In consumer purchases, financial markets, and corporate strategy, what others do matters more to us than the facts. When there's too much information, imitation becomes a convenient heuristic. This is the basis for a self-referential society. Imitation has its virtues, but it also promotes instability and unpredictability. That's because, by definition a multiplier, it can swell a single opinion into a mass movement or catapult the smallest player to the forefront of a market. Mastering the dynamics of self-reference won't ensure mastery of its consequences. But businesses that understand how imitation works can at least attempt to gird themselves against its worst effects--by accounting for it in their forecasts and risk-management plans, by becoming more sensitive to unexpectedly changing circumstances, and by avoiding mindless imitation of other companies' moves. In some instances, they may even be able to build strategies around self-reference and use the tools of imitation to capture new business. That won't make the world any less confusing. But it may make it more profitable. PMID:15202286

  16. Electrostatic Positioning System for a free fall test at drop tower Bremen and an overview of tests for the Weak Equivalence Principle in past, present and future

    Science.gov (United States)

    Sondag, Andrea; Dittus, Hansjörg

    2016-08-01

    The Weak Equivalence Principle (WEP) is at the basis of General Relativity - the best theory for gravitation today. It has been and still is tested with different methods and accuracies. In this paper an overview of tests of the Weak Equivalence Principle done in the past, developed in the present and planned for the future is given. The best result up to now is derived from the data of torsion balance experiments by Schlamminger et al. (2008). An intuitive test of the WEP consists of the comparison of the accelerations of two free falling test masses of different composition. This has been carried through by Kuroda & Mio (1989, 1990) with the up to date most precise result for this setup. There is still more potential in this method, especially with a longer free fall time and sensors with a higher resolution. Providing a free fall time of 4.74 s (9.3 s using the catapult) the drop tower of the Center of Applied Space Technology and Microgravity (ZARM) at the University of Bremen is a perfect facility for further improvements. In 2001 a free fall experiment with high sensitive SQUID (Superconductive QUantum Interference Device) sensors tested the WEP with an accuracy of 10-7 (Nietzsche, 2001). For optimal conditions one could reach an accuracy of 10-13 with this setup (Vodel et al., 2001). A description of this experiment and its results is given in the next part of this paper. For the free fall of macroscopic test masses it is important to start with precisely defined starting conditions concerning the positions and velocities of the test masses. An Electrostatic Positioning System (EPS) has been developed to this purpose. It is described in the last part of this paper.

  17. The perils of the imitation age.

    Science.gov (United States)

    Bonabeau, Eric

    2004-06-01

    Imitation exerts enormous influence over society, and business and finance in particular. And its influence has grown as the avenues by which people imitate--and are imitated--have multiplied and the process has gotten faster. Thousands of communications channels make it possible for virtually anyone in the developed world to know, almost instantaneously, what others do, think, believe, claim, or predict. More significantly, we can and do act upon such knowledge. The resulting fads and fashions, bubbles and crashes are ever more frequent, severe, and complex. The information age has cast up more than its share of paradoxes, including this one: When information is plentiful, we often use it not to make better decisions but to imitate others--and their mistakes. In consumer purchases, financial markets, and corporate strategy, what others do matters more to us than the facts. When there's too much information, imitation becomes a convenient heuristic. This is the basis for a self-referential society. Imitation has its virtues, but it also promotes instability and unpredictability. That's because, by definition a multiplier, it can swell a single opinion into a mass movement or catapult the smallest player to the forefront of a market. Mastering the dynamics of self-reference won't ensure mastery of its consequences. But businesses that understand how imitation works can at least attempt to gird themselves against its worst effects--by accounting for it in their forecasts and risk-management plans, by becoming more sensitive to unexpectedly changing circumstances, and by avoiding mindless imitation of other companies' moves. In some instances, they may even be able to build strategies around self-reference and use the tools of imitation to capture new business. That won't make the world any less confusing. But it may make it more profitable.

  18. Jumping mechanisms and performance in beetles. I. Flea beetles (Coleoptera: Chrysomelidae: Alticini).

    Science.gov (United States)

    Nadein, Konstantin; Betz, Oliver

    2016-07-01

    The present study analyses the anatomy, mechanics and functional morphology of the jumping apparatus, the performance and the kinematics of the natural jump of flea beetles (Coleoptera: Chrysomelidae: Galerucinae: Alticini). The kinematic parameters of the initial phase of the jump were calculated for five species from five genera (average values from minimum to maximum): acceleration 0.91-2.25 (×10(3)) m s(-2), velocity 1.48-2.80 m s(-1), time to take-off 1.35-2.25 ms, kinetic energy 2.43-16.5 µJ, G: -force 93-230. The jumping apparatus is localized in the hind legs and formed by the femur, tibia, femoro-tibial joint, modified metafemoral extensor tendon, extensor ligament, tibial flexor sclerite, and extensor and flexor muscles. The primary role of the metafemoral extensor tendon is seen in the formation of an increased attachment site for the extensor muscles. The rubber-like protein resilin was detected in the extensor ligament, i.e. a short, elastic element connecting the extensor tendon with the tibial base. The calculated specific joint power (max. 0.714 W g(-1)) of the femoro-tibial joint during the jumping movement and the fast full extension of the hind tibia (1-3 ms) suggest that jumping is performed via a catapult mechanism releasing energy that has beforehand been stored in the extensor ligament during its stretching by the extensor muscles. In addition, the morphology of the femoro-tibial joint suggests that the co-contraction of the flexor and the extensor muscles in the femur of the jumping leg is involved in this process. PMID:27385755

  19. Jumping mechanisms and performance in beetles. I. Flea beetles (Coleoptera: Chrysomelidae: Alticini).

    Science.gov (United States)

    Nadein, Konstantin; Betz, Oliver

    2016-07-01

    The present study analyses the anatomy, mechanics and functional morphology of the jumping apparatus, the performance and the kinematics of the natural jump of flea beetles (Coleoptera: Chrysomelidae: Galerucinae: Alticini). The kinematic parameters of the initial phase of the jump were calculated for five species from five genera (average values from minimum to maximum): acceleration 0.91-2.25 (×10(3)) m s(-2), velocity 1.48-2.80 m s(-1), time to take-off 1.35-2.25 ms, kinetic energy 2.43-16.5 µJ, G: -force 93-230. The jumping apparatus is localized in the hind legs and formed by the femur, tibia, femoro-tibial joint, modified metafemoral extensor tendon, extensor ligament, tibial flexor sclerite, and extensor and flexor muscles. The primary role of the metafemoral extensor tendon is seen in the formation of an increased attachment site for the extensor muscles. The rubber-like protein resilin was detected in the extensor ligament, i.e. a short, elastic element connecting the extensor tendon with the tibial base. The calculated specific joint power (max. 0.714 W g(-1)) of the femoro-tibial joint during the jumping movement and the fast full extension of the hind tibia (1-3 ms) suggest that jumping is performed via a catapult mechanism releasing energy that has beforehand been stored in the extensor ligament during its stretching by the extensor muscles. In addition, the morphology of the femoro-tibial joint suggests that the co-contraction of the flexor and the extensor muscles in the femur of the jumping leg is involved in this process.

  20. Break free from the product life cycle.

    Science.gov (United States)

    Moon, Youngme

    2005-05-01

    Most firms build their marketing strategies around the concept of the product life cycle--the idea that after introduction, products inevitably follow a course of growth, maturity, and decline. It doesn't have to be that way, says HBS marketing professor Youngme Moon. By positioning their products in unexpected ways, companies can change how customers mentally categorize them. In doing so, they can shift products lodged in the maturity phase back--and catapult new products forward--into the growth phase. The author describes three positioning strategies that marketers use to shift consumers' thinking. Reverse positioning strips away"sacred" product attributes while adding new ones (JetBlue, for example, withheld the expected first-class seating and in-flight meals on its planes while offering surprising perks like leather seats and extra legroom). Breakaway positioning associates the product with a radically different category (Swatch chose not to associate itself with fine jewelry and instead entered the fashion accessory category). And stealth positioning acclimates leery consumers to a new offering by cloaking the product's true nature (Sony positioned its less-than-perfect household robot as a quirky pet). Clayton Christensen described how new, simple technologies can upend a market. In an analogous way, these positioning strategies can exploit the vulnerability of established categories to new positioning. A company can use these techniques to go on the offensive and transform a category by demolishing its traditional boundaries. Companies that disrupt a category through positioning create a lucrative place to ply their wares--and can leave category incumbents scrambling.

  1. HST/COS FUV Spectrophotometry of the Key Binary Solar Twins 16 Cyg A&B: Astrophysical Laboratories for the Future Sun and Older Solar Analogs

    Science.gov (United States)

    Guinan, Edward

    2014-10-01

    The fortuitous location of the wide G1.5V/G2.5V binary 16 Cyg A&B as the brightest stars in the Kepler Field is a "game changer," permitting the determination of the stars' fundamental properties from asteroseismolgy analyses. Recent studies returned precise determinations of the stars' basic properties including masses and age (6.8+/-0.4 Gyr), along with the rotation periods. Thus, 16 Cyg A&B are now the oldest solar-mass analogs with reliable ages and physical properties. Only the Sun has better determined physical properties. 16 Cyg A&B now serve as old-age anchors for Rotation-Age-Activity-Irradiance relations (and Gyrochronology studies) for solar-type stars. Extensive Ca II HK spectrophotometry reveals low levels of chromospheric emission are below the lowest values for our Sun. These stars serve as critical test beds for studying solar/stellar dynamos for stars less active than the Sun. These advances have catapulted 16 Cyg A&B into a prominent place in solar/stellar astrophysics for studying the evolution, internal structure, magnetic dynamos, angular momentum loss, and FUV irradiances of old solar-mass stars. Although 16 Cyg has been observed from X-ray - IR, there are no observations in the FUV region where most of the crucial diagnostic chromospheric & transition region emissions occur. We request COS FUV medium resolution (G130M, G160M) spectra (six orbits/star). This permits the important FUV (1150-1750A) line emission strengths, profiles and Doppler shifts to be analyzed and compared with the Sun and other solar-analogs. This program is complemented by Ca II HK, high precision uvby observations, and by proposed Chandra X-ray coronal observations.

  2. The extracranial arterial system in the heads of beaked whales, with implications on diving physiology and pathogenesis.

    Science.gov (United States)

    Costidis, Alexander M; Rommel, Sentiel A

    2016-01-01

    Beaked whales are medium-sized toothed whales that inhabit depths beyond the continental shelf; thus beaked whale strandings are relatively infrequent compared to those of other cetaceans. Beaked whales have been catapulted into the spotlight by their tendency to strand in association with naval sonar deployment. Studies have shown the presence of gas and fat emboli within the tissues and analysis of gas emboli is suggestive of nitrogen as the primary component. These findings are consistent with human decompression sickness (DCS) previously not thought possible in cetaceans. Because, tissue loading with nitrogen gas is paramount for the manifestation of DCS and nitrogen loading depends largely on the vascular perfusion of the tissues, we examined the anatomy of the extracranial arterial system using stranded carcasses of 16 beaked whales from five different species. Anatomic regions containing lipid and/or air spaces were prioritized as potential locations of nitrogen gas absorption due to the known solubility of nitrogen in adipose tissue and the nitrogen content of air, respectively. Attention was focused on the acoustic fat bodies and accessory sinus system on the ventral head. We found much of the arterial system of the head to contain arteries homologous to those found in domestic mammals. Robust arterial associations with lipid depots and air spaces occurred within the acoustic fat bodies of the lower jaw and pterygoid air sacs of the ventral head, respectively. Both regions contained extensive trabecular geometry with small arteries investing the trabeculae. Our findings suggest the presence of considerable surface area between the arterial system, and the intramandibular fat bodies and pterygoid air sacs. Our observations may provide support for the hypothesis that these structures play an important role in the exchange of nitrogen gas during diving. PMID:26450139

  3. The buzz on buzz.

    Science.gov (United States)

    Dye, R

    2000-01-01

    Word-of-mouth promotion has become an increasingly potent force, capable of catapulting products from obscurity into runaway commercial successes. Harry Potter, collapsible scooters, the Chrysler PT Cruiser, and The Blair Witch Project are all recent examples of the considerable power of buzz. Yet many top executives and marketing managers are misinformed about the phenomenon and remain enslaved to some common myths. In her article, author Renée Dye explores the truth behind these myths. Myth 1: Only outrageous or edgy products are buzz-worthy. That's simply not true. The most unlikely products, like prescription drugs, can generate tremendous buzz. Myth 2: Buzz just happens. Not so, says Dye. Buzz is increasingly the result of shrewd marketing tactics in which companies seed a vanguard group, ration supplies, use celebrity endorsements, leverage the power of lists, and initiate grassroots marketing. Myth 3: The best buzz-starters are your best customers. Often, a counterculture has a greater ability to start buzz. Myth 4: To profit from buzz, you must act first and fast. In fact, copycat companies can reap substantial profits if they know when and when not to jump in. Myth 5: The media and advertising are needed to create buzz. When used either too early or too much, the media and advertising can squelch buzz before it ignites. As globalization and brand proliferation continue, writes Dye, buzz may come to dominate the shaping of markets. Indeed, companies that are unable to control buzz may soon find the phenomenon controlling them. PMID:11184968

  4. MicroRNA Profiling of Laser-Microdissected Hepatocellular Carcinoma Reveals an Oncogenic Phenotype of the Tumor Capsule

    Directory of Open Access Journals (Sweden)

    Jan Peveling-Oberhag

    2014-12-01

    Full Text Available Several microRNAs (miRNAs are associated with the molecular pathogenesis of hepatocellular carcinoma (HCC. However, previous studies analyzing the dysregulation of miRNAs in HCC show heterogeneous results. We hypothesized that part of this heterogeneity might be attributable to variations of miRNA expression deriving from the HCC capsule or the fibrotic septa within the peritumoral tissue used as controls. Tissue from surgically resected hepatitis C–associated HCC from six well-matched patients was microdissected using laser microdissection and pressure catapulting technique. Four distinct histologic compartments were isolated: tumor parenchyma (TP, fibrous capsule of the tumor (TC, tumor-adjacent liver parenchyma (LP, and cirrhotic septa of the tumor-adjacent liver (LC. MiRNA expression profiling analysis of 1105 mature miRNAs and precursors was performed using miRNA microarray. Principal component analysis and consecutive pairwise supervised comparisons demonstrated distinct patterns of expressed miRNAs not only for TP versus LP (e.g., intratumoral down-regulation of miR-214, miR-199a, miR-146a, and miR-125a; P< .05 but also for TC versus LC (including down-regulation within TC of miR-126, miR-99a/100, miR-26a, and miR-125b; P< .05. The tumor capsule therefore demonstrates a tumor-like phenotype with down-regulation of well-known tumor-suppressive miRNAs. Variations of co-analyzed fibrotic tissue within the tumor or in controls may have profound influence on miRNA expression analyses in HCC. Several miRNAs, which are proposed to be HCC specific, may indeed be rather associated to the tumor capsule. As miRNAs evolve to be important biomarkers in liver tumors, the presented data have important translational implications on diagnostics and treatment in patients with HCC.

  5. MicroRNA Profiling of Laser-Microdissected Hepatocellular Carcinoma Reveals an Oncogenic Phenotype of the Tumor Capsule123

    Science.gov (United States)

    Peveling-Oberhag, Jan; Seiz, Anna; Döring, Claudia; Hartmann, Sylvia; Köberle, Verena; Liese, Juliane; Zeuzem, Stefan; Hansmann, Martin-Leo; Piiper, Albrecht

    2014-01-01

    Several microRNAs (miRNAs) are associated with the molecular pathogenesis of hepatocellular carcinoma (HCC). However, previous studies analyzing the dysregulation of miRNAs in HCC show heterogeneous results. We hypothesized that part of this heterogeneity might be attributable to variations of miRNA expression deriving from the HCC capsule or the fibrotic septa within the peritumoral tissue used as controls. Tissue from surgically resected hepatitis C–associated HCC from six well-matched patients was microdissected using laser microdissection and pressure catapulting technique. Four distinct histologic compartments were isolated: tumor parenchyma (TP), fibrous capsule of the tumor (TC), tumor-adjacent liver parenchyma (LP), and cirrhotic septa of the tumor-adjacent liver (LC). MiRNA expression profiling analysis of 1105 mature miRNAs and precursors was performed using miRNA microarray. Principal component analysis and consecutive pairwise supervised comparisons demonstrated distinct patterns of expressed miRNAs not only for TP versus LP (e.g., intratumoral down-regulation of miR-214, miR-199a, miR-146a, and miR-125a; P< .05) but also for TC versus LC (including down-regulation within TC of miR-126, miR-99a/100, miR-26a, and miR-125b; P< .05). The tumor capsule therefore demonstrates a tumor-like phenotype with down-regulation of well-known tumor-suppressive miRNAs. Variations of co-analyzed fibrotic tissue within the tumor or in controls may have profound influence on miRNA expression analyses in HCC. Several miRNAs, which are proposed to be HCC specific, may indeed be rather associated to the tumor capsule. As miRNAs evolve to be important biomarkers in liver tumors, the presented data have important translational implications on diagnostics and treatment in patients with HCC. PMID:25500075

  6. Expansion of CD4(+ CD25(+ and CD25(- T-Bet, GATA-3, Foxp3 and RORγt cells in allergic inflammation, local lung distribution and chemokine gene expression.

    Directory of Open Access Journals (Sweden)

    You Lu

    Full Text Available Allergic asthma is associated with airway eosinophilia, which is regulated by different T-effector cells. T cells express transcription factors T-bet, GATA-3, RORγt and Foxp3, representing Th1, Th2, Th17 and Treg cells respectively. No study has directly determined the relative presence of each of these T cell subsets concomitantly in a model of allergic airway inflammation. In this study we determined the degree of expansion of these T cell subsets, in the lungs of allergen challenged mice. Cell proliferation was determined by incorporation of 5-bromo-2'-deoxyuridine (BrdU together with 7-aminoactnomycin (7-AAD. The immunohistochemical localisation of T cells in the lung microenvironments was also quantified. Local expression of cytokines, chemokines and receptor genes was measured using real-time RT-PCR array analysis in tissue sections isolated by laser microdissection and pressure catapulting technology. Allergen exposure increased the numbers of T-bet(+, GATA-3(+, RORγt(+ and Foxp3(+ cells in CD4(+CD25(+ and CD4(+CD25(- T cells, with the greatest expansion of GATA-3(+ cells. The majority of CD4(+CD25(+ T-bet(+, GATA-3(+, RORγt(+ and Foxp3(+ cells had incorporated BrdU and underwent proliferation during allergen exposure. Allergen exposure led to the accumulation of T-bet(+, GATA-3(+ and Foxp3(+ cells in peribronchial and alveolar tissue, GATA-3(+ and Foxp3(+ cells in perivascular tissue, and RORγt(+ cells in alveolar tissue. A total of 28 cytokines, chemokines and receptor genes were altered more than 3 fold upon allergen exposure, with expression of half of the genes claimed in all three microenvironments. Our study shows that allergen exposure affects all T effector cells in lung, with a dominant of Th2 cells, but with different local cell distribution, probably due to a distinguished local inflammatory milieu.

  7. Interest of the MICROSTAR Accelerometer to improve the GRASP Mission.

    Science.gov (United States)

    Perrot, E.; Lebat, V.; Foulon, B.; Christophe, B.; Liorzou, F.; Huynh, P. A.

    2015-12-01

    The Geodetic Reference Antenna in Space (GRASP) is a micro satellite mission concept proposed by JPL to improve the definition of the Terrestrial Reference Frame (TRF). GRASP collocates GPS, SLR, VLBI, and DORIS sensors on a dedicated spacecraft in order to establish precise and stable ties between the key geodetic techniques used to define and disseminate the TRF. GRASP also offers a space-based reference antenna for the present and future Global Navigation Satellite Systems (GNSS). By taking advantage of the new testing possibilities offer by the catapult facility at the ZARM drop tower, the ONERA's space accelerometer team proposes an up-dated version, called MICROSTAR, of its ultra sensitive electrostatic accelerometers which have contributed to the success of the last Earth's gravity missions GRACE and GOCE. Built around a cubic proof-mass, it provides the 3 linear accelerations with a resolution better than 10-11 ms-2/Hz1/2 into a measurement bandwidth between 10-3 Hz and 0.1 Hz and the 3 angular accelerations about its 3 orthogonal axes with 5´10-10 rad.s-2/Hz1/2 resolution. Integrated at the centre of mass of the satellite, MICROSTAR improves the Precise Orbit Determination (POD) by accurate measurement of the non-gravitational force acting on the satellite. It offers also the possibility to calibrate the change in the position of the satellite center of mass with an accuracy better than 100 μm as demonstrated in the GRACE mission. Assuming a sufficiently rigid structure between the antennas and the accelerometer, its data can participate to reach the mission objective of 1 mm precision for the TRF position.

  8. Actions of motor neurons and leg muscles in jumping by planthopper insects (hemiptera, issidae).

    Science.gov (United States)

    Burrows, Malcolm; Bräunig, Peter

    2010-04-15

    To understand the catapult mechanism that propels jumping in a planthopper insect, the innervation and action of key muscles were analyzed. The large trochanteral depressor muscle, M133b,c, is innervated by two motor neurons and by two dorsal unpaired median (DUM) neurons, all with axons in N3C. A smaller depressor muscle, M133a, is innervated by two neurons, one with a large-diameter cell body, a large, blind-ending dendrite, and a giant ovoid, axon measuring 50 microm by 30 microm in nerve N5A. The trochanteral levator muscles (M132) and (M131) are innervated by N4 and N3B, respectively. The actions of these muscles in a restrained jump were divisible into a three-phase pattern. First, both hind legs were moved into a cocked position by high-frequency bursts of spikes in the levator muscles lasting about 0.5 seconds. Second, and once both legs were cocked, M133b,c received a long continuous sequence of motor spikes, but the two levators spiked only sporadically. The spikes in the two motor neurons to M133b,c on one side were closely coupled to each other and to the spikes on the other side. If one hind leg was cocked then the spikes only occurred in motor neurons to that side. The final phase was the jump movement itself, which occurred when the depressor spikes ceased and which lasted 1 ms. Muscles 133b,c activated synchronously on both sides, are responsible for generating the power, and M133a and its giant neuron may play a role in triggering the release of a jump. PMID:20151364

  9. Use of integrated technology in team sports: a review of opportunities, challenges, and future directions for athletes.

    Science.gov (United States)

    Dellaserra, Carla L; Gao, Yong; Ransdell, Lynda

    2014-02-01

    Integrated technology (IT), which includes accelerometers, global positioning systems (GPSs), and heart rate monitors, has been used frequently in public health. More recently, IT data have been used in sports settings to assess training and performance demands. However, the impact of IT in sports settings is yet to be evaluated, particularly in field-based team sports. This narrative-qualitative review provides an overview of the emerging impact of IT in sports settings. Twenty electronic databases (e.g., Medline, SPORTdiscus, and ScienceDirect), print publications (e.g., Signal Processing Magazine and Catapult Innovations news releases), and internet resources were searched using different combinations of keywords as follows: accelerometers, heart rate monitors, GPS, sport training, and field-based sports for relevant articles published from 1990 to the present. A total of 114 publications were identified, and 39 that examined a field-based team sport using a form of IT were analyzed. The articles chosen for analysis examined a field-based team sport using a form of IT. The uses of IT can be divided into 4 categories: (a) quantifying movement patterns (n = 22), (b) assessing the differences between demands of training and competition (n = 12), (c) measuring physiological and metabolic responses (n = 16), and (d) determining a valid definition for velocity and a sprint effort (n = 8). Most studies used elite adult male athletes as participants and analyzed the sports of Australian Rules football, field hockey, cricket, and soccer, with sample sizes between 5 and 20 participants. The limitations of IT in a sports setting include scalability issues, cost, and the inability to receive signals within indoor environments. Integrated technology can contribute to significant improvements in the preparation, training, and recovery aspects of field-based team sports. Future research should focus on using IT with female athlete populations and developing resources to use IT

  10. Aerospace Workforce Development: The Nebraska Proposal; and Native View Connections: A Multi-Consortium Workforce Development Proposal. UNO Aviation Monograph Series

    Science.gov (United States)

    Bowen, Brent D.; Russell, Valerie; Vlasek, Karisa; Avery, Shelly; Calamaio, Larry; Carstenson, Larry; Farritor, Shane; deSilva, Shan; Dugan, James; Farr, Lynne

    2003-01-01

    The NASA Nebraska Space Grant Consortium (NSGC) continues to recognize the necessity of increasing the quantity and quality of highly skilled graduates and faculty involved with NASA. Through NASA Workforce Development funds awarded in 2002, NSGC spearheaded customer- focused workforce training and higher education, industry and community partnerships that are significantly impacting the state s workforce in the science, technology, engineering, and mathematics (STEM) competencies. NSGC proposes to build upon these accomplishments to meet the steadily increasing demand for STEM skills and to safeguard minority representation in these disciplines. A wide range of workforce development activities target NASA s need to establish stronger connections among higher education, industry, and community organizations. Participation in the National Student Satellite Program (NSSP), Community Internship Program, and Nebraska Science and Technology Recruitment Fair will extend the pipeline of employees benefiting NASA as well as Nebraska. The diversity component of this proposal catapults from the exceptional reputation NSGC has built by delivering geospatial science experiences to Nebraska s Native Americans. For 6 years, NSGC has fostered and sustained partnerships with the 2 tribal colleges and 4 reservation school districts in Nebraska to foster aeronautics education and outreach. This program, the Nebraska Native American Outreach Program (NNAOP), has grown to incorporate more than educational institutions and is now a partnership among tribal community leaders, academia, tribal schools, and industry. The content focus has broadened from aeronautics in the school systems to aerospace technology and earth science applications in tribal community decision-making and workforce training on the reservations. To date, participants include faculty and staff at 4 Nebraska tribal schools, 2 tribal colleges, approximately 1,000 Native American youth, and over 1,200 community members

  11. Epitope mapping of conformational V2-specific anti-HIV human monoclonal antibodies reveals an immunodominant site in V2.

    Directory of Open Access Journals (Sweden)

    Luzia M Mayr

    Full Text Available In the case-control study of the RV144 vaccine trial, the levels of antibodies to the V1V2 region of the gp120 envelope glycoprotein were found to correlate inversely with risk of HIV infection. This recent demonstration of the potential role of V1V2 as a vaccine target has catapulted this region into the focus of HIV-1 research. We previously described seven human monoclonal antibodies (mAbs derived from HIV-infected individuals that are directed against conformational epitopes in the V1V2 domain. In this study, using lysates of SF162 pseudoviruses carrying V1V2 mutations, we mapped the epitopes of these seven mAbs. All tested mAbs demonstrated a similar binding pattern in which three mutations (F176A, Y177T, and D180L abrogated binding of at least six of the seven mAbs to ≤15% of SF162 wildtype binding. Binding of six or all of the mAbs was reduced to ≤50% of wildtype by single substitutions at seven positions (168, 180, 181, 183, 184, 191, and 193, while one change, V181I, increased the binding of all mAbs. When mapped onto a model of V2, our results suggest that the epitope of the conformational V2 mAbs is located mostly in the disordered region of the available crystal structure of V1V2, overlapping and surrounding the α4β7 binding site on V2.

  12. Functional food red yeast rice (RYR) for metabolic syndrome amelioration: a review on pros and cons.

    Science.gov (United States)

    Patel, Seema

    2016-05-01

    Red yeast rice (RYR), the fermentation product of mold Monascus purpureus has been an integral part of Oriental food and traditional Chinese medicine, long before the discovery of their medicinal roles. With the identification of bioactive components as polyketide pigments (statins), and unsaturated fatty acids, RYR has gained a nutraceutical status. Hypercholesterolemic effect of this fermented compound has been validated and monacolin K has been recognized as the pivotal component in cholesterol alleviation. Functional similarity with commercial drug lovastatin sans the side effects has catapulted its popularity in other parts of the world as well. Apart from the hypotensive role, ameliorative benefits of RYR as anti-inflammatory, antidiabetic, anticancer and osteogenic agent have emerged, fueling intense research on it. Mechanistic studies have revealed their interaction with functional agents like coenzyme Q10, astaxanthin, vitamin D, folic acid, policosanol, and berberine. On the other hand, concurrence of mycotoxin citrinin and variable content of statin has marred its integration in mainstream medication. In this disputable scenario, evaluation of the scopes and lacunae to overcome seems to contribute to an eminent area of healthcare. Red yeast rice (RYR), the rice-based fermentation product of mold Monascus purpureus is a functional food. Its bioactive component monacolin K acts like synthetic drug lovastatin, without the severe side effects of the latter. RYR has been validated to lower cholesterol, control high blood pressure; confer anti-flammation, hypoglycaemic, anticancer and osteogenic properties. However, dose inconsistency and co-occurrence of toxin citrinin hampers its dietary supplementation prospect. Further research might facilitate development of RYR as a nutraceutical. PMID:27038957

  13. Inductive matrix completion for predicting gene–disease associations

    Science.gov (United States)

    Natarajan, Nagarajan; Dhillon, Inderjit S.

    2014-01-01

    Motivation: Most existing methods for predicting causal disease genes rely on specific type of evidence, and are therefore limited in terms of applicability. More often than not, the type of evidence available for diseases varies—for example, we may know linked genes, keywords associated with the disease obtained by mining text, or co-occurrence of disease symptoms in patients. Similarly, the type of evidence available for genes varies—for example, specific microarray probes convey information only for certain sets of genes. In this article, we apply a novel matrix-completion method called Inductive Matrix Completion to the problem of predicting gene-disease associations; it combines multiple types of evidence (features) for diseases and genes to learn latent factors that explain the observed gene–disease associations. We construct features from different biological sources such as microarray expression data and disease-related textual data. A crucial advantage of the method is that it is inductive; it can be applied to diseases not seen at training time, unlike traditional matrix-completion approaches and network-based inference methods that are transductive. Results: Comparison with state-of-the-art methods on diseases from the Online Mendelian Inheritance in Man (OMIM) database shows that the proposed approach is substantially better—it has close to one-in-four chance of recovering a true association in the top 100 predictions, compared to the recently proposed Catapult method (second best) that has bigdata.ices.utexas.edu/project/gene-disease. Contact: naga86@cs.utexas.edu PMID:24932006

  14. Electrostatic Accelerometer for the Gravity Recovery and Climate Experiment Follow-On Mission (GRACE FO)

    Science.gov (United States)

    Perrot, Eddy; Boulanger, Damien; Christophe, Bruno; Foulon, Bernard; Liorzou, Françoise; Lebat, Vincent

    2014-05-01

    micro-gravity pendulum bench and with drops in ZARM catapult. The post-processing needed to achieve the performance, in particular with regards to the temperature stability, will be explained.

  15. Zinc and Copper Balances During 3 Weeks of Bed Rest, With or Without Artificial Gravity

    Science.gov (United States)

    Heacox, Hayley

    2016-01-01

    mineral balances for control and AG-treated subjects during bed rest. These findings, in conjunction with the calcium data, provide evidence for preservation of zinc and copper by AG, suggesting that effects on muscle outweigh losses from bone. My project has been a true laboratory experience. Based upon this experience, I have decided to pursue a doctoral degree in analytical chemistry. Afterward, I am considering conducting a postdoctoral fellowship at JSC in the Nutritional Biochemistry Lab in hopes to catapult my career within such laboratory. I have really found my niche within this laboratory, and I believe this is my place in the NASA community

  16. Estado social de derecho o estado de opinión: dilema sin resolver en América Latina

    Directory of Open Access Journals (Sweden)

    Orlando José Cadrazco Salcedo

    2010-01-01

    catapult or a ruleror government at a particular status.Key Words:Social State of Law, State of Opinion, Government, Democracy, Constitution, Population, Surveys, Media,Social Rights.

  17. Jumping performance of planthoppers (Hemiptera, Issidae).

    Science.gov (United States)

    Burrows, Malcolm

    2009-09-01

    The structure of the hind limbs and the kinematics of their movements that propel jumping in planthopper insects (Hemiptera, Auchenorrhyncha, Fulgoroidea, Issidae) were analysed. The propulsion for a jump was delivered by rapid movements of the hind legs that both move in the same plane beneath the body and parallel to its longitudinal axis, as revealed in high-speed sequences of images captured at rates up to 7500 images s(-1). The first and key movement was the depression of both trochantera about their coxae, powered by large depressor muscles in the thorax, accompanied by rapid extension of the tibiae about their femora. The initial movements of the two trochantera of the hind legs were synchronised to within 0.03 ms. The hind legs are only 20% longer than the front and middle legs, represent 65% of the body length, and have a ratio of 1.8 relative to the cube root of the body mass. The two hind coxae have a different structure to those in frog- and leafhoppers. They are fused at the mid-line, covered ventrally by transparent cuticle, and each is fixed laterally to a part of the internal skeleton called the pleural arch that extends to the articulation of a hind wing. A small and pointed, ventral coxal protrusion covered in microtrichia engages with a raised, smooth, white patch on a dorsal femur when a hind leg is levated (cocked) in preparation for a jump. In the best jumps by a male Issus, the body was accelerated in 0.8 ms to a take-off velocity of 5.5 m s(-1), was subjected to a force of 719 g and was displaced a horizontal distance of 1.1 m. This performance required an energy output of 303 microJ, a power output of 388 mW and exerted a force of 141 mN, or more than 700 times its body mass. This performance implies that a catapult mechanism must be used, and that Issus ranks alongside the froghopper Philaenus as one of the best insect jumpers. PMID:19684220

  18. The Sea Around Us

    Science.gov (United States)

    Carson, Rachel L.

    1991-12-01

    Published in 1951, The Sea Around Us is one of the most remarkably successful books ever written about the natural world. Rachel Carson's rare ability to combine scientific insight with moving, poetic prose catapulted her book to first place on The New York Times best-seller list, where it enjoyed wide attention for thirty-one consecutive weeks. It remained on the list for more than a year and a half and ultimately sold well over a million copies, has been translated into 28 languages, inspired an Academy Award-winning documentary, and won both the 1952 National Book Award and the John Burroughs Medal. This classic work remains as fresh today as when it first appeared. Carson's writing teems with stunning, memorable images--the newly formed Earth cooling beneath an endlessly overcast sky; the centuries of nonstop rain that created the oceans; giant squids battling sperm whales hundreds of fathoms below the surface; and incredibly powerful tides moving 100 billion tons of water daily in the Bay of Fundy. Quite simply, she captures the mystery and allure of the ocean with a compelling blend of imagination and expertise. Reintroducing a classic work to a whole new generation of readers, this Special Edition features a new chapter written by Jeffrey Levinton, a leading expert in marine ecology, that brings the scientific side of The Sea Around Us completely up to date. Levinton incorporates the most recent thinking on continental drift, coral reefs, the spread of the ocean floor, the deterioration of the oceans, mass extinction of sea life, and many other topics. In addition, acclaimed nature writer Ann Zwinger has contributed a brief foreword. Today, with the oceans endangered by the dumping of medical waste and ecological disasters such as the Exxon oil spill in Alaska, this illuminating volume provides a timely reminder of both the fragility and the importance of the ocean and the life that abounds within it. Anyone who loves the sea, or who is concerned about our

  19. Public-Private Collaborations with Earth-Space Benefits

    Science.gov (United States)

    Davis, Jeffrey R.; Richard, Elizabeth E.

    2014-01-01

    ; the World Biomimetic Foundation in Spain who is interested in advancing the use of biomimicry to provide technical solutions in many industries; Satellite Application Catapult in London, England who interested in pursuing U.S. collaborations with the Space and Life Sciences Innovation Centre under development in Scotland; and DLR in Cologne, Germany who developed :envihab, a collaborative facility for partners to pursue research and technology projects of mutual interest. The NHHPC has sponsored two global networking forums on innovation by partners Wyle, NASA, and DLR, was featured in the 2013 Humans in Space Symposium Panel on "NHHPC and :envihab - reach out to Future Markets," and is working on an international meeting for Spring 2014 in Cologne with :envihab.

  20. Fiabilidad intra-participante de diferentes modelos de dispositivos GPS implementados en un partido de Fútbol 7

    Directory of Open Access Journals (Sweden)

    Julen Castellano

    2010-01-01

    Full Text Available El objetivo de este estudio fue estimar la fiabilidad intra-participante de tres modelos de GPS (Global Positioning System MinimaxX (Catapult Innovations, Australia, SPI10 y WiSpi (GPSports, Australia que operan a una frecuencia de 5,1 y 1 Hz, respectivamente. Se midieron distancias recorridas a distintas intensidades a 5 jugadores de fútbol (edad, 20,1 ± 1,2 años; altura, 176,3 ± 9,9 cm; peso, 63,5 ± 8,4 kg en un partido de entrenamiento de 33 min, en un campo de fútbol-7 (6 jugadores de campo y 1 portero. La distancia total recorrida (DT media fue de 3.288,8 m para los modelos MinimaxX, 3.050,3 m para el WiSPI y de 3.247,5 m para el SPI10. La velocidad máxima obtenida por cada modelo fue de 30.3 km·h-1 en los dispositivos MinimaxX, y de 25,1 y de 25.2 km·h-1 en los dispositivos WiSPI y SPI10, respectivamente. Se estimó el coeficiente de variación (CV entre los 3 modelos estudiados para la distancia recorrida en cada uno de los 4 niveles de velocidad, así como para la distancia total recorrida, y la velocidad media y máxima, siendo el tamaño de la muestra la principal limitación. En base a los resultados podemos concluir que los diferentes dispositivos presentan una alta fiabilidad para medir la distancia total recorrida y las recorridas en categorías de baja velocidad. Sin embargo la velocidad de los desplazamientos realizados durante el partido condiciona la fiabilidad de los diferentes dispositivos, aumentando la dispersión de las medidas obtenidas (CV a medida que se incrementa la velocidad de carrera; especialmente cuando se supera la velocidad de 13 km·h-1.

  1. SOME REASONS OF DISPLACES OF THE NOMADIC TRIBES IN EURASIA AND EXAMPLE OF THE BLACK DEATH IN CAFFA, 1346

    Directory of Open Access Journals (Sweden)

    Assoc. Prof. Dr. Mehmet TEZCAN

    2008-09-01

    Full Text Available The nomadic tribes in Eurasian steppes, adopted a manner oflife in nomadism, were scarcely abandoning their own residences, towhich caused some factors like generally epidemics, famines, locustattacks, or dangerous foreign threats just as oppressions by theXiongnu (to the Yuezhi or the Chinese (to the Xiongnu etc. Beingone of the reasons which led the nomadic tribes as far as to theWestern Asia and the Middle Europe, the epidemics appeared also inEurasia from the very beginnings of the history and during the MiddleAges, and spread out in the Central Asia that was on the greatcommercial routes, through the great Silk Roads in general.The epidemic named as “Black Death” appeared north of theBlack Sea in Caffa in 1346 and very influenced Medieval Europenegatively, which, there existed the period of the “Hundred Years’War”. However, there is not any exact information about its origin.According to the available information and the report by Gabriele de’Mussi, it occurred first in China in 1320s, and expanded into the NearEast rapidly through the invasion routes of the Mongol armies andcommercial ones. When Janibek Khan, the khan of the Golden Hordebegan again to besiege Caffa in 1345, the Black Death occurredamong the Mongol army. And the two Genoese ships, departed fromCaffa and came in the Mediterranean Sea in 1347, caused itsexpansion to the whole European countries, except for only Polandand Czechoslovakia, in 1348-49, and then, to Russia in 1351-53.Consequently, thirty per cent of the European population perished.As to how the epidemic influenced the nomadic world inEurasia, there is not enough information about it. However, thanks toit, we can reach to some interesting valuable data about Mongolstrategies of warfare: upon that many Mongolian soldiers of theMongolian army died due to this epidemic, the Mongol khan heldresponsible the Genoese in Caffa for the death. He made their corpses thrown into the citadel by catapults, and then

  2. Two Islands, One Commodity: Cuba, Java, and the Global Sugar Trade (1790-1930

    Directory of Open Access Journals (Sweden)

    Jonathan Curry-Machado

    2012-12-01

    Full Text Available Sugar had become, by the eighteenth century, a global commodity. Originating in East Asia, plantations in the Americas fed the growing taste for its use in Europe, with its consumption increasingly popularised. The 1791 Revolution in Saint Domingue (Haiti and the 1807 British abolition of the slave trade prompted shifts in the epicentres of sugar, the most important of these being arguably to Cuba and Java. These two fertile islands saw the burgeoning development of sugar-plantation systems with major inputs of foreign capital and forced labour. In the process the two islands each, respectively, became central to the very much truncated Spanish and Dutch colonial empires left after the Napoleonic wars and the Latin American wars of liberation; and by the mid-nineteenth century in the case of Cuba, and by the late nineteenth century in the case of Java, they had been catapulted to global sugar pre-eminence. There has been an abundance of study on the two islands each in their own right, but none systematically examines their parallel trajectories. Yet the question arises as to how sugar came to dominate the agriculture, industry and trade of these two islands; and how these two islands in particular, in two different colonial systems and parts of the world, should rise to sugar pre-eminence in the way they did and when they did. Are there connections and similarities between the two that help explain this phenomenon? This article analyses the conditions that led Java and Cuba to become the prime cane-sugar exporters of the nineteenth and early twentieth centuries. Initiative for this came from the linkages between their dominant elites and the transnational, transimperial networks of trade and capital. This furthered the stimulation of technological and scientific innovation in both, enabled not only through the introduction of the latest advances in machinery and method, but also the immigration of technical skilled workers from Europe and North

  3. Inspiring the Next Generation of Engineers and Scientists

    Science.gov (United States)

    Tambara, Kevin

    2013-04-01

    catapults and bridges, egg drop "lunar landers", egg-passenger car crashes, cardboard boat races (with human passengers), and working roller coasters made with only paper and tape. Each project requires minimal, low-cost materials commonly found at home or in local stores. I will share the most common student misperceptions about inquiry and problem-solving I have observed while working alongside my students during these projects.

  4. El espejismo nacional-socialista. La relación entre dos catedráticos de Prehistoria, Oswald Menghin y Julio Martínez Santa-Olalla (1935-1952

    Directory of Open Access Journals (Sweden)

    Mederos Martín, Alfredo

    2014-12-01

    Full Text Available Oswald Menghin, Professor of Prehistoric Man at the University of Vienna from 1922-45, supported the unity of Austria with Germany, and a sympathizer about the NSDAP ideas on the need to avoid racial mixing between Aryans and Jews. During his time as Professor at the University of Fouad in Cairo from 1930-33 he came into contact with Hermann Junker. This radicalized Menghin’s views and, as a result, he wrote his book, Spirit and Blood. The Basic Principles of Race, Language, Culture and Nation. His time as Rector of the University of Viena from 1936 to 1937 catapulted him into politics: he was a board member of the Austrian fascist party, Vaterländische Front from 1936 to 1937 and was appointed Minister of Education between March and May 1938, just after Hitler’s invasion of Austria. As Minister, he applied for membership in the NSDAP, but because his prior membership in secret Catholic organizations, it was not accepted until June 1940. Menghin was in contact with Martinez Santa-Olalla, after the celebration of the Jubilee of the Institute for Cultural Morphology at Frankfurt in June and July 1938. After Almagro Basch’s research period in Germany and Austria in January and February 1942 and his own visit to Barcelona in June 1942, however, Menghin chose to distance from Martinez Santa-Olalla, not visiting Madrid, cutting the epistolary relationship and reporting negatively about him to the SS-Ahnenerbe. After being imprisoned in two American concentration camps between May 1945 and February 1947, Menghin fled to Argentina in 1948, followed shortly afterwards by his wife and daughter. In Argentina Menghin was supported by Jose Imbelloni, director of the Ethnographic Museum at the University of Buenos Aires since 1947, who hired him as a researcher without teaching. He also received support from Martinez Santa-Olalla through the Spanish Ambassador, Jose Maria de Areilza, and from the Professor of History at the University of Buenos Aires

  5. Moon (Form-Origin)

    Science.gov (United States)

    Tsiapas, Elias

    2016-04-01

    above mentioned process, the thick clouds surrounding Earth-Moon were causing heavy storms and on the outer surface of the rolling Moon, wherever small cavities - or pockets - existed, these would fill up with water. Then, due to the Moon's changing tilt, these pockets were sealed by sediments and as a result, small water tanks are scattered on the successive layers of the Moon, from its centre to its surface. . As this sphere (the Moon) continued to grow, the Earth-Moon system was displaying a double-planet image. The Moon's reverse rolling velocity increased according to the increase of its mass and volume. As the temperature on the surface of the Earth continued to fall, a larger number of bigger sized solid masses were descending from the poles towards the equator, and the Moon could no longer aggregate them. The gathering and interference of solid rocks of great mass acted as the catapult on which the Moon bounced off the Earth and was put into orbit around it.

  6. The science of the lunar poles

    Science.gov (United States)

    Lucey, P. G.

    2011-12-01

    imaging of interiors of polar shadowed craters has been accomplished by many instruments from the ultraviolet to the radar. Imaging radars on Chandrayaan-1 and LRO have identified anomalous craters that may contain rich water ice deposits. Neutron spectrometers on Lunar Prospector and LRO directly detected hydrogen enhancements at both poles. Spectacularly, the LCROSS impact experiment detected a wide range of volatile elements and species at Cabeus crater in the lunar south polar region. While these measurements have catapulted polar science forward, much remains to be understood about the polar system, both from analysis of the current data, and new missions planned and in development. The general state of the lunar atmosphere is planned to be addressed by the UV and neutral mass spectrometers carried by the planned NASA LADEE (Lunar Atmosphere And Dust Environment Explorer) spacecraft creating an important baseline. But more data is necessary, from an in situ direct assay of polar volatiles to measurements of species and fluxes into and out of the cold traps over lengthy timescales.

  7. PV solar electricity: status and future

    Science.gov (United States)

    Hoffmann, Winfried

    2006-04-01

    Within the four main market segments of PV solar electricity there are already three areas competitive today. These are off-grid industrial and rural as well as consumer applications. The overall growth within the past 8 years was almost 40 % p.a. with a "normal" growth of about 18 % p.a. for the first three market segments whereas the grid connected market increased with an astonishing 63 % p.a. The different growth rates catapulted the contribution of grid connected systems in relation to the total market from about one quarter 6 years ago towards more than three quarters today. The reason for this development is basically due to industry-politically induced market support programs in the aforementioned countries. It is quite important to outline under which boundary conditions grid connected systems will be competitive without support programs like the feed in tariff system in Germany, Spain and some more to come in Europe as well as investment subsidies in Japan, US and some other countries. It will be shown that in a more and more liberalized utility market worldwide electricity produced by PV solar electricity systems will be able to compete with their generating cost against peak power prices from utilities. The point of time for this competitiveness is mainly determined by the following facts: 1. Price decrease for PV solar electricity systems leading to an equivalent decrease in the generated cost for PV produced kWh. 2. Development of a truly liberalized electricity market. 3. Degree of irradiation between times of peak power demand and delivery of PV electricity. The first topic is discussed using price experience curves. Some explanations will be given to correlate the qualitative number of 20 % price decrease for doubling cumulative worldwide sales derived from the historic price experience curve with a more quantitative analysis based on our EPIA-Roadmap (productivity increase and ongoing improvements for existing technologies as well as development

  8. Fundamentals of Physics, Part 2 (Chapters 12-20)

    Science.gov (United States)

    Halliday, David; Resnick, Robert; Walker, Jearl

    2003-12-01

    Chapter 12 Equilibrium and Elasticity. What injury can occur to a rock climber hanging by a crimp hold? 12-1 What Is Physics? 12-2 Equilibrium. 12-3 The Requirements of Equilibrium. 12-4 The Center of Gravity. 12-5 Some Examples of Static Equilibrium. 12-6 Indeterminate Structures. 12-7 Elasticity. Review & Summary Questions Problems. Chapter 13 Gravitation. What lies at the center of our Milky Way galaxy? 13-1 What Is Physics? 13-2 Newton's Law of Gravitation. 13-3 Gravitation and the Principle of Superposition. 13-4 Gravitation Near Earth's Surface. 13-5 Gravitation Inside Earth. 13-6 Gravitational Potential Energy. 13-7 Planets and Satellites: Kepler's Laws. 13-8 Satellites: Orbits and Energy. 13-9 Einstein and Gravitation. Review & Summary Questions Problems. Chapter 14 Fluids. What causes ground effect in race car driving? 14-1 What Is Physics? 14-2 What Is a Fluid? 14-3 Density and Pressure. 14-4 Fluids at Rest. 14-5 Measuring Pressure. 14-6 Pascal's Principle. 14-7 Archimedes' Principle. 14-8 Ideal Fluids in Motion. 14-9 The Equation of Continuity. 14-10 Bernoulli's Equation. Review & SummaryQuestionsProblems. Chapter 15 Oscillations. What is the "secret" of a skilled diver's high catapult in springboard diving? 15-1 What Is Physics? 15-2 Simple Harmonic Motion. 15-3 The Force Law for Simple Harmonic Motion. 15-4 Energy in Simple Harmonic Motion. 15-5 An Angular Simple Harmonic Oscillator. 15-6 Pendulums. 15-7 Simple Harmonic Motion and Uniform Circular Motion. 15-8 Damped Simple Harmonic Motion. 15-9 Forced Oscillations and Resonance. Review & Summary Questions Problems. Chapter 16 Waves--I. How can a submarine wreck be located by distant seismic stations? 16-1 What Is Physics? 16-2 Types of Waves. 16-3 Transverse and Longitudinal Waves. 16-4 Wavelength and Frequency. 16-5 The Speed of a Traveling Wave. 16-6 Wave Speed on a Stretched String. 16-7 Energy and Power of a Wave Traveling Along a String. 16-8 The Wave Equation. 16-9 The Principle of Superposition

  9. Methods of Mathematical and Computational Physics for Industry, Science, and Technology

    Science.gov (United States)

    Melnik, Roderick V. N.; Voss, Frands

    2006-11-01

    Many industrial problems provide scientists with important and challenging problems that need to be solved today rather than tomorrow. The key role of mathematical physics, modelling, and computational methodologies in addressing such problems continues to increase. Science has never been exogenous to applied research. Gigantic ships and steam engines, repeating catapult of Dionysius and the Antikythera `computer' invented around 80BC are just a few examples demonstrating a profound link between theoretical and applied science in the ancient world. Nowadays, many industrial problems are typically approached by groups of researchers who are working as a team bringing their expertise to the success of the entire enterprise. Since the late 1960s several groups of European mathematicians and scientists have started organizing regular meetings, seeking new challenges from industry and contributing to the solution of important industrial problems. In particular, this often took the format of week-long workshops originally initiated by the Oxford Study Groups with Industry in 1968. Such workshops are now held in many European countries (typically under the auspices of the European Study Groups with Industry - ESGI), as well as in Australia, Canada, the United States, and other countries around the world. Problems given by industrial partners are sometimes very difficult to complete within a week. However, during a week of brainstorming activities these problems inevitably stimulate developing fruitful new ideas, new approaches, and new collaborations. At the same time, there are cases where as soon as the problem is formulated mathematically, it is relatively easy to solve. Hence, putting the industrial problem into a mathematical framework, based on physical laws, often provides a key element to the success. In addition to this important first step, the value in such cases is the real, practical applicability of the results obtained for an industrial partner who presents

  10. La réservation de sièges dans les corps élus en Inde Reservation of Seats in Elected Bodies in India

    Directory of Open Access Journals (Sweden)

    David Annoussamy

    2009-03-01

    Full Text Available La Constitution de 1950 a prévu la réservation des sièges à la chambre basse fédérale et dans les assemblées législatives des Etats fédérés en faveur des castes répertoriées (anciens intouchables et des tribus répertoriées, proportionnellement à leur effectif dans la population totale. Ce procédé a eu pour effet d'éveiller et de développer la conscience politique de ces catégories qui ont maintenant des partis politiques à eux. Cependant la réservation qui avait été conçue comme une mesure provisoire devant durer 10 ans a été renouvelée tous les 10 ans, aucun parti politique n'osant s'y opposer de peur de perdre les voix de ces catégories de population.Cette réservation a été étendue aux sièges des conseils municipaux et aux postes de maires par une révision constitutionnelle de 1992. Mais son application a  soulevé des protestations sur le terrain, les gens de caste élevée ne voulant pas accepter comme maire un ancien intouchable.La même révision a réservé aux femmes 1/3 de postes de maires et de sièges dans les conseils municipaux. Pour l'instant les élues sont des prête-noms pour leur mari, père ou frère. Cela ne tire pas à conséquence dans les conseils mais les femmes sans aucune idée de l'administration catapultées au rôle de maire éprouvent des difficultés.Un projet de révision constitutionnelle  accordant la même réservation aux femmes à la chambre basse fédérale et dans les assemblées des Etats, élaborée en 1996 sur la recommandation  de Nations unies n'arrive pas à recueillir l'adhésion des partis politiques dominés par les hommes.The Constitution of India which came into force in 1950 provides for the reservation of seats in the lower house of the Union and the legislative assemblies of States in favour of Scheduled castes (ex -intouchables and Scheduled tribes proportionately to their number in the total population. That measure had the effect of arousing and

  11. RELIABILITY AND ACCURACY OF 10 HZ GPS DEVICES FOR SHORT-DISTANCE EXERCISE

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    Julen Castellano

    2011-03-01

    Full Text Available The use of GPS technology for training and research purposes requires a study of the reliability, validity and accuracy of the data generated (Petersen et al., 2009. To date, studies have focused on devices with a logging rate of 1 Hz and 5 Hz (Coutts and Duffield, 2010; Duffield et al., 2010; Jennings et al., 2010; MacLeod et al., 2009; Petersen et al., 2009; Portas et al., 2010, although it seems that more frequent sampling can increase the accuracy of the information provided by these devices (Jennings et al., 2010; MacLeod et al., 2009, Portas et al., 2010. However, we are unaware of any study of the reliability and accuracy of GPS devices using a sampling frequency of 10 Hz. Thus, the aim of the present research was to determine the reliability and accuracy of GPS devices operating at a sampling frequency of 10 Hz, in relation here to sprints of 15 m and 30 m and using both video and photoelectric cells.Nine trained male athletes participated in the study. Each participant completed 7 and 6 linear runs of 15 m and 30 m, respectively (n = 117, with only one GPS device being used per participant. Each repetition required them to complete the route as quickly as possible, with 1 min recovery between sets. Distance was monitored through the use of GPS devices (MinimaxX v4.0, Catapult Innovations, Melbourne, Australia operating at the above mentioned sampling frequency of 10 Hz. In addition, all tests were filmed with a video camera operating at a sampling frequency of 25 frames. Data were collected during what were considered to be good GPS conditions in terms of the weather and satellite conditions (number of satellites = 10.0 ± 0.2 and 10.3 ± 0.4 for sprints of 15 m and 30 m, respectively.Distance was measured using a tape measure. Electronic timing gates (TAG- Heuer, CP 520 Training model, Switzerland were used to obtain a criterion sprint time accurate to 0.01 s, with gates being placed at the beginning and end of the route (Petersen et

  12. Book Review:

    Science.gov (United States)

    Webb, Steve

    2008-11-01

    The Polish physicist Józio (Joseph, Josh, Jo) Rotblat was catapulted into the public eye when he (and the 'Pugwash Conferences' organization) received the 1995 Nobel Peace Prize. His life prior to that had been most distinguished but conducted well out of the public eye. Born and raised as a Jewish physicist in pre-World War II Poland, and thus potentially educationally disadvantaged, he battled away for education and scientific achievement. He came to Liverpool University just before the outbreak of World War II, worked in James Chadwick's laboratory on the early beginnings of neutron fission physics, moved to Los Alamos to take part in the US-UK collaborative Manhattan Project to build a nuclear bomb and was motivated by a desire to rid Poland of Nazi 'racial cleansing'. On realizing the US-UK goal was somewhat wider, he resigned this work and dedicated his life to the peaceful uses of radiation and the campaigns to rid the world of the potential world-eliminating possibility of nuclear war. For this purpose he interacted with Albert Einstein and Bertrand Russell, and in July 1957 founded the 'Pugwash Conferences', named for a small fishing village in Nova Scotia, Canada where the first was held. Along the way his personal life was no less dramatic. Cruel events conspired, and his wife Tola remained in Poland and was killed in the Nazi extermination camp at Majdanek. He grieved for his beloved Poland and those left behind or unaccounted for. He was suspected by some Americans of being a spy and had his personal papers and family artefacts impounded. After the war he was Professor of Medical Physics at St Bartholomew's Hospital, London for 30 years up to retirement. After John Roberts, he was the second editor of this journal Physics in Medicine and Biology from 1961-72 (see e.g. Bob Burns' paper in our 50th birthday issue, 2006. Kit Hill's little book which chronicles the life and times of Rotblat weaves together the key events in his personal and professional

  13. People

    Science.gov (United States)

    2001-01-01

    underneath me; I really wanted to be catapulted into a different culture. Going to teach in Zimbabwe just meant fulfilling an awful lot of things in one go really - teaching science as well as going to live in a completely different place and being the only white person for 60 miles. But I didn't want to teach in a school forever. With something like science communication, and the joy of working on this exhibition at @Bristol for example, I've been able to try to appeal to all ages and kinds of people. And I've also been able to use different media, such as hands-on exhibits or computers, give talks or run events. What do you think the role of the exhibition is? We're much more interested in getting people excited, motivated and inspired by science and natural history rather than just trying to get across facts. We also think it's important to enable people to feel more confident about their own science and feel they can have a view about science issues. Do you have a wide range of visitors from primary school children to adults? Absolutely. I think a lot of people see hands-on science centres as being places for kids and we really wanted to make sure that teenagers, adults and senior citizens would see it as a place that was appropriate for them. So we actually split the exhibition up into four different areas in order to appeal to different age groups in different ways. For instance our area on the brain and body is more appropriate for teenagers, adults and senior citizens; small children will still find fun things to do, but there are other areas that are much more engaging for them. Whereas for adults finding out about themselves, finding out what they react to emotionally, finding out more about sex and reproduction, is something that they have responded to really well. And the great thing has been seeing teenagers coming in, choosing to come to a science centre on a Saturday afternoon. Quite a few teenagers have said that they came here with their families and now

  14. Fundamentals of Physics, Volume 1, (Chapters 1 - 21)

    Science.gov (United States)

    Walker, Jearl

    2004-01-01

    skilled diver's high catapult in springboard diving? 15-1 What Is Physics? 15-2 Simple Harmonic Motion. 15-3 The Force Law for Simple Harmonic Motion. 15-4 Energy in Simple Harmonic Motion. 15-5 An Angular Simple Harmonic Oscillator. 15-6 Pendulums. 15-7 Simple Harmonic Motion and Uniform Circular Motion. 15-8 Damped Simple Harmonic Motion. 15-9 Forced Oscillations and Resonance. Review & Summary. Questions. Problems. Chapter 16. Waves--I. How can a submarine wreck be located by distant seismic stations? 16-1 What Is Physics? 16-2 Types of Waves. 16-3 Transverse and Longitudinal Waves. 16-4 Wavelength and Frequency. 16-5 The Speed of a Traveling Wave. 16-6 Wave Speed on a Stretched String. 16-7 Energy and Power of a Wave Traveling Along a String. 16-8 The Wave Equation. 16-9 The Principle of Superposition for Waves. 16-10 Interference of Waves. 16-11 Phasors. 16-12 Standing Waves. 16-13 Standing Waves and Resonance. Review & Summary. Questions. Problems. Chapter 17. Waves--II. How can an emperor penguin .nd its mate among thousands of huddled penguins? 17-1 What Is Physics? 17-2 Sound Waves. 17-3 The Speed of Sound. 17-4 Traveling Sound Waves. 17-5 Interference. 17-6 Intensity and Sound Level. 17-7 Sources of Musical Sound. 17-8 Beats. 17-9 The Doppler Effect. 17-10 Supersonic Speeds, Shock Waves. Review & Summary. Questions. Problems. Chapter 18. Temperature, Heat, and the First Law of Thermodynamics. How can a dead rattlesnake detect and strike a reaching hand? 18-1 What Is Physics? 18-2 Temperature. 18-3 The Zeroth Law of Thermodynamics. 18-4 Measuring Temperature. 18-5 The Celsius and Fahrenheit Scales. 18-6 Thermal Expansion. 18-7 Temperature and Heat. 18-8 The Absorption of Heat by Solids and Liquids. 18-9 A Closer Look at Heat and Work. 18-10 The First Law of Thermodynamics. 18-11 Some Special Cases of the First Law of Thermodynamics. 18-12 Heat Transfer Mechanisms. Review & Summary. Questions. Problems. Chapter 19. The Kinetic Theory of Gases. How can cooling

  15. An Interview with David Dabydeen on Literature and Politics

    Directory of Open Access Journals (Sweden)

    Ruzbeh Babaee

    2016-07-01

    t know what true freedom or independence mean, we are all constrained and liberated and catapulted into creativity by being with each other. However, I recall what Walcott said about slavery: that the enslaved African being herded to the cane fields would have seen something sensationally beautiful along the way, given how lush Caribbean landscapes are. A hummingbird or kiskadee or blue-saki or brightly coloured viper…Walcott said that such encounters with beauty were moments of freedom which could only be partially understood, partially described, because they also contained the seeds of tragedy and terror. If you venture into Guyana’s rainforest, you will experience the sublime which contain elemental terror and a tragic sense of how life is constantly being destroyed and remade and destroyed by tooth and claw.[1] Ruzbeh Babaee[2] David Dabydeen