Autonomous unmanned air vehicles (UAV) techniques
NASA Astrophysics Data System (ADS)
Hsu, Ming-Kai; Lee, Ting N.
2007-04-01
The UAVs (Unmanned Air Vehicles) have great potentials in different civilian applications, such as oil pipeline surveillance, precision farming, forest fire fighting (yearly), search and rescue, boarder patrol, etc. The related industries of UAVs can create billions of dollars for each year. However, the road block of adopting UAVs is that it is against FAA (Federal Aviation Administration) and ATC (Air Traffic Control) regulations. In this paper, we have reviewed the latest technologies and researches on UAV navigation and obstacle avoidance. We have purposed a system design of Jittering Mosaic Image Processing (JMIP) with stereo vision and optical flow to fulfill the functionalities of autonomous UAVs.
2009-12-11
Abrams tanks and M2A3 Bradley fighting vehicles. The cities and villages had many obstacles such as narrow congested roads with single and multiple story...M1A2 tanks and M2A3 Bradley Fighting Vehicles were ―worth their weight in gold-when they rolled, the bad guys took notice and when they fired, the
Hindrances to bistable front propagation: application to Wolbachia invasion.
Nadin, Grégoire; Strugarek, Martin; Vauchelet, Nicolas
2018-05-01
We study the biological situation when an invading population propagates and replaces an existing population with different characteristics. For instance, this may occur in the presence of a vertically transmitted infection causing a cytoplasmic effect similar to the Allee effect (e.g. Wolbachia in Aedes mosquitoes): the invading dynamics we model is bistable. We aim at quantifying the propagules (what does it take for an invasion to start?) and the invasive power (how far can an invading front go, and what can stop it?). We rigorously show that a heterogeneous environment inducing a strong enough population gradient can stop an invading front, which will converge in this case to a stable front. We characterize the critical population jump, and also prove the existence of unstable fronts above the stable (blocking) fronts. Being above the maximal unstable front enables an invading front to clear the obstacle and propagate further. We are particularly interested in the case of artificial Wolbachia infection, used as a tool to fight arboviruses.
Capability Portfolio Analysis Tool (CPAT) Verification and Validation Report
2013-01-01
BFSB Battlefield Surveillance Brigade BFV Bradley Fighting Vehicle BMOD Bradley Modernization C2 (H) Command and Control (HBCT) C2 (S...Fire Infantry Fighting Vehicle (IFV); Fire Integrated Support Team (FIST); Engineer (Eng); Cavalry (CAV) BFV FOV CDD Block II - 16 Apr 2010 GCV FOV
Crisis management with applicability on fire fighting plants
NASA Astrophysics Data System (ADS)
Panaitescu, M.; Panaitescu, F. V.; Voicu, I.; Dumitrescu, L. G.
2017-08-01
The paper presents a case study for a crisis management analysis which address to fire fighting plants. The procedures include the steps of FTA (Failure tree analysis). The purpose of the present paper is to describe this crisis management plan with tools of FTA. The crisis management procedures have applicability on anticipated and emergency situations and help to describe and planning a worst-case scenario plan. For this issue must calculate the probabilities in different situations for fire fighting plants. In the conclusions of paper is analised the block diagram with components of fire fighting plant and are presented the solutions for each possible risk situations.
Vision-Based UAV Flight Control and Obstacle Avoidance
2006-01-01
denoted it by Vb = (Vb1, Vb2 , Vb3). Fig. 2 shows the block diagram of the proposed vision-based motion analysis and obstacle avoidance system. We denote...structure analysis often involve computation- intensive computer vision tasks, such as feature extraction and geometric modeling. Computation-intensive...First, we extract a set of features from each block. 2) Second, we compute the distance between these two sets of features. In conventional motion
Female genital mutilations - a testimony.
Youssouf, Samia
2013-02-01
In Djibouti, the prevalence of female genital mutilations (FGMs) amounts to 98% and the practice is still in use. When I left, in 1999, I knew I would involve myself in the fight against FGMs and I describe here the outcome of an obstacle course of more than ten years duration. This paper is written on behalf of innumerable women, who could give you a similar account.
Collective strategy for obstacle navigation during cooperative transport by ants.
McCreery, Helen F; Dix, Zachary A; Breed, Michael D; Nagpal, Radhika
2016-11-01
Group cohesion and consensus have primarily been studied in the context of discrete decisions, but some group tasks require making serial decisions that build on one another. We examine such collective problem solving by studying obstacle navigation during cooperative transport in ants. In cooperative transport, ants work together to move a large object back to their nest. We blocked cooperative transport groups of Paratrechina longicornis with obstacles of varying complexity, analyzing groups' trajectories to infer what kind of strategy the ants employed. Simple strategies require little information, but more challenging, robust strategies succeed with a wider range of obstacles. We found that transport groups use a stochastic strategy that leads to efficient navigation around simple obstacles, and still succeeds at difficult obstacles. While groups navigating obstacles preferentially move directly toward the nest, they change their behavior over time; the longer the ants are obstructed, the more likely they are to move away from the nest. This increases the chance of finding a path around the obstacle. Groups rapidly changed directions and rarely stalled during navigation, indicating that these ants maintain consensus even when the nest direction is blocked. Although some decisions were aided by the arrival of new ants, at many key points, direction changes were initiated within the group, with no apparent external cause. This ant species is highly effective at navigating complex environments, and implements a flexible strategy that works for both simple and more complex obstacles. © 2016. Published by The Company of Biologists Ltd.
NASA Astrophysics Data System (ADS)
Nouri-Borujerdi, Ali; Moazezi, Arash
2018-01-01
The current study investigates the conjugate heat transfer characteristics for laminar flow in backward facing step channel. All of the channel walls are insulated except the lower thick wall under a constant temperature. The upper wall includes a insulated obstacle perpendicular to flow direction. The effect of obstacle height and location on the fluid flow and heat transfer are numerically explored for the Reynolds number in the range of 10 ≤ Re ≤ 300. Incompressible Navier-Stokes and thermal energy equations are solved simultaneously in fluid region by the upwind compact finite difference scheme based on flux-difference splitting in conjunction with artificial compressibility method. In the thick wall, the energy equation is obtained by Laplace equation. A multi-block approach is used to perform parallel computing to reduce the CPU time. Each block is modeled separately by sharing boundary conditions with neighbors. The developed program for modeling was written in FORTRAN language with OpenMP API. The obtained results showed that using of the multi-block parallel computing method is a simple robust scheme with high performance and high-order accurate. Moreover, the obtained results demonstrated that the increment of Reynolds number and obstacle height as well as decrement of horizontal distance between the obstacle and the step improve the heat transfer.
Evacuation simulation with consideration of obstacle removal and using game theory
NASA Astrophysics Data System (ADS)
Lin, Guan-Wen; Wong, Sai-Keung
2018-06-01
In this paper, we integrate a cellular automaton model with game theory to simulate crowd evacuation from a room with consideration of obstacle removal. The room has one or more exits, one of which is blocked by obstacles. The obstacles at the exit can be removed by volunteers. We investigate the cooperative and defective behaviors of pedestrians during evacuation. The yielder game and volunteer's dilemma game are employed to resolve interpedestrian conflict. An anticipation floor field is proposed to guide the pedestrians to avoid obstacles that are being removed. We conducted experiments to determine how a variety of conditions affect overall crowd evacuation and volunteer evacuation times. The conditions were the start time of obstacle removal, number of obstacles, placement of obstacles, time spent in obstacle removal, strength of the anticipation floor field, and obstacle visibility distance. We demonstrate how reciprocity can be achieved among pedestrians and increases the efficiency of the entire evacuation process.
Robotic follow system and method
Bruemmer, David J [Idaho Falls, ID; Anderson, Matthew O [Idaho Falls, ID
2007-05-01
Robot platforms, methods, and computer media are disclosed. The robot platform includes perceptors, locomotors, and a system controller, which executes instructions for a robot to follow a target in its environment. The method includes receiving a target bearing and sensing whether the robot is blocked front. If the robot is blocked in front, then the robot's motion is adjusted to avoid the nearest obstacle in front. If the robot is not blocked in front, then the method senses whether the robot is blocked toward the target bearing and if so, sets the rotational direction opposite from the target bearing, and adjusts the rotational velocity and translational velocity. If the robot is not blocked toward the target bearing, then the rotational velocity is adjusted proportional to an angle of the target bearing and the translational velocity is adjusted proportional to a distance to the nearest obstacle in front.
Writing Blocks and Tacit Knowledge.
ERIC Educational Resources Information Center
Boice, Robert
1993-01-01
A review of the literature on writing block looks at two kinds: inability to write in a timely, fluent fashion, and reluctance by academicians to assist others in writing. Obstacles to fluent writing are outlined, four historical trends in treating blocks are discussed, and implications are examined. (MSE)
NASA Astrophysics Data System (ADS)
Wang, Po-Jen; Keyawa, Nicholas R.; Euler, Craig
2012-01-01
In order to achieve highly accurate motion control and path planning for a mobile robot, an obstacle avoidance algorithm that provided a desired instantaneous turning radius and velocity was generated. This type of obstacle avoidance algorithm, which has been implemented in California State University Northridge's Intelligent Ground Vehicle (IGV), is known as Radial Polar Histogram (RPH). The RPH algorithm utilizes raw data in the form of a polar histogram that is read from a Laser Range Finder (LRF) and a camera. A desired open block is determined from the raw data utilizing a navigational heading and an elliptical approximation. The left and right most radii are determined from the calculated edges of the open block and provide the range of possible radial paths the IGV can travel through. In addition, the calculated obstacle edge positions allow the IGV to recognize complex obstacle arrangements and to slow down accordingly. A radial path optimization function calculates the best radial path between the left and right most radii and is sent to motion control for speed determination. Overall, the RPH algorithm allows the IGV to autonomously travel at average speeds of 3mph while avoiding all obstacles, with a processing time of approximately 10ms.
... myeloma by strengthening the immune system to fight cancer cells. It treats ENL by blocking the action ... infections, and Kaposi's sarcoma (a type of skin cancer). Thalidomide has also been used to treat some ...
Learn to Avoid or Overcome Leadership Obstacles
ERIC Educational Resources Information Center
D'Auria, John
2015-01-01
Leadership is increasingly recognized as an important factor in moving schools forward, yet we have been relatively random in how we prepare and support them. Four obstacles often block or diminish their effectiveness. Avoiding or overcoming each of these requires an underlying set of skills and knowledge that we believe can be learned and…
State of the fight against informal market of medicines in Togo: approaches and limitations.
Gnassingbe, A; Flahault, A; Geissbuhler, A; Sprumont, D; Awesso, A
2018-02-01
The extent of medicines sales and consumption in the informal market in Togo raises many ethical and public health issues. In order to report on the situation of public action in the fight against this practice, we conducted a qualitative survey from 15 to 25 February 2016 in the commune of Lomé and in the Maritime Region among the actors of control system and resource people in the general population. This was supplemented by an analysis of Togo's pharmaceutical and health policy documents and a literature review on the illicit drug market issues relating to public health, political science, the social sciences applied to health. In spite of the existence of national and international tools, household poverty, cultural self-medication, ignorance of the population concerning the health risks of informal market medicines, weak political commitment, weakness regulation and enforcement, corruption, constitute obstacles to the success of actions to combat this practice.
Worden, Timothy A; Mendes, Matthew; Singh, Pratham; Vallis, Lori Ann
2016-10-01
Successful planning and execution of motor strategies while concurrently performing a cognitive task has been previously examined, but unfortunately the varied and numerous cognitive tasks studied has limited our fundamental understanding of how the central nervous system successfully integrates and executes these tasks simultaneously. To gain a better understanding of these mechanisms we used a set of cognitive tasks requiring similar central executive function processes and response outputs but requiring different perceptual mechanisms to perform the motor task. Thirteen healthy young adults (20.6±1.6years old) were instrumented with kinematic markers (60Hz) and completed 5 practice, 10 single-task obstacle walking trials and two 40 trial experimental blocks. Each block contained 20 trials of seated (single-task) trials followed by 20 cognitive and obstacle (30% lower leg length) crossing trials (dual-task). Blocks were randomly presented and included either an auditory Stroop task (AST; central interference only) or a visual Stroop task (VST; combined central and structural interference). Higher accuracy rates and shorter response times were observed for the VST versus AST single-task trials (p<0.05). Conversely, for the obstacle stepping performance, larger dual task costs were observed for the VST as compared to the AST for clearance measures (the VST induced larger clearance values for both the leading and trailing feet), indicating VST tasks caused greater interference for obstacle crossing (p<0.05). These results supported the hypothesis that structural interference has a larger effect on motor performance in a dual-task situation compared to cognitive tasks that pose interference at only the central processing stage. Copyright © 2016 Elsevier B.V. All rights reserved.
Chen, Xueye; Zhao, Zhongyi
2017-04-29
This paper aims at layout optimization design of obstacles in a three-dimensional T-type micromixer. Numerical analysis shows that the direction of flow velocity change constantly due to the obstacles blocking, which produces the chaotic convection and increases species mixing effectively. The orthogonal experiment method was applied for determining the effects of some key parameters on mixing efficiency. The weights in the order are: height of obstacles > geometric shape > symmetry = number of obstacles. Based on the optimized results, a multi-units obstacle micromixer was designed. Compared with T-type micromixer, the multi-units obstacle micromixer is more efficient, and more than 90% mixing efficiency were obtained for a wide range of peclet numbers. It can be demonstrated that the presented optimal design method of obstacles layout in three-dimensional microchannels is a simple and effective technology to improve species mixing in microfluidic devices. The obstacles layout methodology has the potential for applications in chemical engineering and bioengineering. Copyright © 2017 Elsevier B.V. All rights reserved.
Block by Block: The Challenges of Urban Operations
2003-01-01
So the game of measures and coun- termeasures—the adult, and much more deadly, version of the familiar children’s game of rock, scissors, paper—has...January 1995 that, even when badly outmanned and outequipped, the city offered them unique advantages— familiarity with the terrain, the element of... familiar with the conditions of urban fighting was Ratko Mladiæ. He later emerged as the overall Bosnian Serb commander at Sarajevo. Third, the
During fighting, American lobsters urinate on each other with antennule flicking highest during this period. Blocking excretion of urine obliterates previously established dominance relationships, suggesting that individual recognition requires a urine signal (Breithaupt et al.,...
R [to the Fifth Power]: The Sustained Silent Reading Makeover that Transformed Readers
ERIC Educational Resources Information Center
Kelley, Michelle; Clausen-Grace, Nicki
2006-01-01
This article reports on a retooled Sustained Silent Reading (SSR) block in an intermediate classroom designed to meet the needs of all students. The authors discuss the benefits and obstacles to SSR and include the framework and classroom management tips that aided their successful implementation of an independent reading block. Students engaged…
Imaging behind opaque obstacle: a potential method for guided in vitro needle placement
Perinchery, Sandeep Menon; Shinde, Anant; Matham, Murukeshan Vadakke
2016-01-01
We report a simple real time optical imaging concept using an axicon lens to image the object kept behind opaque obstacles in free space. The proposed concept underlines the importance and advantages of using an axicon lens compared to a conventional lens to image behind the obstacle. The potential of this imaging concept is demonstrated by imaging the insertion of surgical needle in biological specimen in real time, without blocking the field of view. It is envisaged that this proposed concepts and methodology can make a telling impact in a wide variety of areas especially for diagnostics, therapeutics and microscopy applications. PMID:28018744
Why do winners keep winning? Androgen mediation of winner but not loser effects in cichlid fish
Oliveira, Rui F.; Silva, Ana; Canário, Adelino V.M.
2009-01-01
Animal conflicts are influenced by social experience such that a previous winning experience increases the probability of winning the next agonistic interaction, whereas a previous losing experience has the opposite effect. Since androgens respond to social interactions, increasing in winners and decreasing in losers, we hypothesized that socially induced transient changes in androgen levels could be a causal mediator of winner/loser effects. To test this hypothesis, we staged fights between dyads of size-matched males of the Mozambique tilapia (Oreochromis mossambicus). After the first contest, winners were treated with the anti-androgen cyproterone acetate and losers were supplemented with 11-ketotestosterone. Two hours after the end of the first fight, two contests were staged simultaneously between the winner of the first fight and a naive male and between the loser of first fight and another naive male. The majority (88%) of control winners also won the second interaction, whereas the majority of control losers (87%) lost their second fight, thus confirming the presence of winner/loser effects in this species. As predicted, the success of anti-androgen-treated winners in the second fight decreased significantly to chance levels (44%), but the success of androgenized losers (19%) did not show a significant increase. In summary, the treatment with anti-androgen blocks the winner effect, whereas androgen administration fails to reverse the loser effect, suggesting an involvement of androgens on the winner but not on the loser effect. PMID:19324741
Identification and analysis of obstacles in bioterrorism preparedness and response
NASA Astrophysics Data System (ADS)
Sincavage, Suzanne Michele
The focus of this study was to identify and analyze the obstacles to bioterrorism preparedness and response facing emergency management agencies and public authorities. In order to establish the limits of this discussion, the obstacles will examine a combined conceptual framework of public health, environmental security and social response. The interdisciplinary characteristics of this framework are ideal for addressing the issue of bioterrorism because of its simultaneous impact, which encompasses the complex interrelationships that pertain to public health and national security and social response. Based on a review of literature, the obstacles presented range from the absence of an effective surveillance system for biological terrorism related diseases to the inadequate training of first responders in bioterrorism preparedness and the difficult challenges of a mass casualty situation and the intense pressures associated with the crisis response. Furthermore, the impending reality of bioterrorism will further illustrate a close examination of the characteristics and management of three major biowarfare agents---anthrax, plague and smallpox. Finally, to provide a realistic understanding of the impact of bioterrorism, three case studies of actual events and two hypothetical scenarios will be discussed. Specifically, the discussion will provide the following three unconventional terrorist attacks: the recent anthrax attacks of 2001, the Aum Shinrikyo's attack of the Tokyo subway in 1995, and the Rajneeshees' use of salmonella poisoning in 1994. The inclusion of the hypothetical scenarios of two massive outbreaks of smallpox and anthrax will be presented to illuminate the seriousness and magnitude of the threat of bioterrorism and the probable consequences of failing to overcome the obstacles presented in this study. The importance of this research cannot be overemphasized, the threat is undeniably serious, and the potential for biological agents to cause devastating casualties can be minimized with the fighting strength of education.
Critical Care Nurses' Perceptions of End-of-Life Care Obstacles: Comparative 17-Year Data.
Beckstrand, Renea L; Lamoreaux, Nicole; Luthy, Karlen E; Macintosh, Janelle L B
Nurses working in intensive care units (ICUs) frequently care for patients and their families at the end of life (EOL). Providing high-quality EOL care is important for both patients and families, yet ICU nurses face many obstacles that hinder EOL care. Researchers have identified various ICU nurse-perceived obstacles, but no studies have been found addressing the progress that has been made for the last 17 years. The aims of this study were to determine the most common and current obstacles in EOL care as perceived by ICU nurses and then to evaluate whether meaningful changes have occurred since data were first gathered in 1998. A quantitative-qualitative mixed methods design was used. A random, geographically dispersed sample of 2000 members of the American Association of Critical-Care Nurses was surveyed. Five obstacle items increased in mean score and rank as compared with 1999 data including (1) family not understanding what the phrase "lifesaving measures" really means, (2) providing lifesaving measures at families' requests despite patient's advance directive listing no such care, (3) family not accepting patient's poor prognosis, (4) family members fighting about the use of life support, and (5) not enough time to provide EOL care because the nurse is consumed with lifesaving measures attempting to save the patient's life. Five obstacle items decreased in mean score and rank compared with 1999 data including (1) physicians differing in opinion about care of the patient, (2) family and friends who continually call the nurse rather than calling the designated family member, (3) physicians who are evasive and avoid families, (4) nurses having to deal with angry families, and (5) nurses not knowing their patient's wishes regarding continuing with tests and treatments. Obstacles in EOL care, as perceived by critical care nurses, still exist. Family-related obstacles have increased over time. Obstacles related to families may not be easily overcome as each family, dealing with a dying family member in an ICU, likely has not previously experienced a similar situation. On the basis of the current top 5 obstacles, recommendations for possible areas of focus include (1) improved health literacy assessment of families followed by earlier directed, appropriate, and specific EOL information; (2) improved physician/team communication; and (3) ensuring patients' wishes are followed as written. In general, patient- and family-centered care using clear and open EOL communication regarding wishes and desires between patients and families, their physicians, and nurses will help decrease common obstacles, thus improving the quality of EOL care provided to dying patients and families.
Unions Striking Back at Bills to Curb Labor
ERIC Educational Resources Information Center
Sawchuk, Stephen
2011-01-01
Besieged by state proposals to eviscerate collective bargaining, eliminate teacher tenure, and make it harder to collect dues, teachers' unions are fighting back. Lawsuits supported by local union affiliates have for now blocked anti-union legislation in Alabama and Wisconsin. E-mail "blasts," phone banks, and rallies are also among the…
In a new study published November 23, 2016, in Molecular Cell, researchers in the CCR’s Laboratory of Cell and Developmental Signaling reported the discovery of a previously unknown route for blocking cell growth that can be activated by certain chemotherapy drugs to fight cancer. Read more...
77 FR 16903 - National Day of Honor
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-22
... and unwavering commitment to duty, our men and women in uniform served tour after tour, fighting block... their love of country, nearly 4,500 men and women are eternally bound; though we have laid them to rest... through trials, we will always emerge stronger than before. Now, our Nation reaffirms our commitment to...
Bi-stability in cooperative transport by ants in the presence of obstacles
Pinkoviezky, Itai; Feinerman, Ofer
2018-01-01
To cooperatively carry large food items to the nest, individual ants conform their efforts and coordinate their motion. Throughout this expedition, collective motion is driven both by internal interactions between the carrying ants and a response to newly arrived informed ants that orient the cargo towards the nest. During the transport process, the carrying group must overcome obstacles that block their path to the nest. Here, we investigate the dynamics of cooperative transport, when the motion of the ants is frustrated by a linear obstacle that obstructs the motion of the cargo. The obstacle contains a narrow opening that serves as the only available passage to the nest, and through which single ants can pass but not with the cargo. We provide an analytical model for the ant-cargo system in the constrained environment that predicts a bi-stable dynamic behavior between an oscillatory mode of motion along the obstacle and a convergent mode of motion near the opening. Using both experiments and simulations, we show how for small cargo sizes, the system exhibits spontaneous transitions between these two modes of motion due to fluctuations in the applied force on the cargo. The bi-stability provides two possible problem solving strategies for overcoming the obstacle, either by attempting to pass through the opening, or take large excursions to circumvent the obstacle. PMID:29746457
Bi-stability in cooperative transport by ants in the presence of obstacles.
Ron, Jonathan E; Pinkoviezky, Itai; Fonio, Ehud; Feinerman, Ofer; Gov, Nir S
2018-05-01
To cooperatively carry large food items to the nest, individual ants conform their efforts and coordinate their motion. Throughout this expedition, collective motion is driven both by internal interactions between the carrying ants and a response to newly arrived informed ants that orient the cargo towards the nest. During the transport process, the carrying group must overcome obstacles that block their path to the nest. Here, we investigate the dynamics of cooperative transport, when the motion of the ants is frustrated by a linear obstacle that obstructs the motion of the cargo. The obstacle contains a narrow opening that serves as the only available passage to the nest, and through which single ants can pass but not with the cargo. We provide an analytical model for the ant-cargo system in the constrained environment that predicts a bi-stable dynamic behavior between an oscillatory mode of motion along the obstacle and a convergent mode of motion near the opening. Using both experiments and simulations, we show how for small cargo sizes, the system exhibits spontaneous transitions between these two modes of motion due to fluctuations in the applied force on the cargo. The bi-stability provides two possible problem solving strategies for overcoming the obstacle, either by attempting to pass through the opening, or take large excursions to circumvent the obstacle.
An Obstacle-Tolerant Path Planning Algorithm for Mobile-Anchor-Node-Assisted Localization
Tsai, Rong-Guei
2018-01-01
The location information obtained using a sensor is a critical requirement in wireless sensor networks. Numerous localization schemes have been proposed, among which mobile-anchor-node-assisted localization (MANAL) can reduce costs and overcome environmental constraints. A mobile anchor node (MAN) provides its own location information to assist the localization of sensor nodes. Numerous path planning schemes have been proposed for MANAL, but most scenarios assume the absence of obstacles in the environment. However, in a realistic environment, sensor nodes cannot be located because the obstacles block the path traversed by the MAN, thereby rendering the sensor incapable of receiving sufficient three location information from the MAN. This study proposes the obstacle-tolerant path planning (OTPP) approach to solve the sensor location problem owing to obstacle blockage. OTPP can approximate the optimum beacon point number and path planning, thereby ensuring that all the unknown nodes can receive the three location information from the MAN and reduce the number of MAN broadcast packet times. Experimental results demonstrate that OTPP performs better than Z-curves because it reduces the total number of beacon points utilized and is thus more suitable in an obstacle-present environment. Compared to the Z-curve, OTPP can reduce localization error and improve localization coverage. PMID:29547582
Symbiotic Navigation in Multi-Robot Systems with Remote Obstacle Knowledge Sharing
Ravankar, Abhijeet; Ravankar, Ankit A.; Kobayashi, Yukinori; Emaru, Takanori
2017-01-01
Large scale operational areas often require multiple service robots for coverage and task parallelism. In such scenarios, each robot keeps its individual map of the environment and serves specific areas of the map at different times. We propose a knowledge sharing mechanism for multiple robots in which one robot can inform other robots about the changes in map, like path blockage, or new static obstacles, encountered at specific areas of the map. This symbiotic information sharing allows the robots to update remote areas of the map without having to explicitly navigate those areas, and plan efficient paths. A node representation of paths is presented for seamless sharing of blocked path information. The transience of obstacles is modeled to track obstacles which might have been removed. A lazy information update scheme is presented in which only relevant information affecting the current task is updated for efficiency. The advantages of the proposed method for path planning are discussed against traditional method with experimental results in both simulation and real environments. PMID:28678193
High Resolution Image From Viking Lander 1
1996-12-12
NASA's Viking 1 took this high-resolution picture today, its third day on Mars. Distance from the camera to the nearfield (bottom) is about 4 meters (13 feet); to the horizon, about 3 kilometers (1.8 miles). The photo shows numerous angular blocks ranging in size from a few centimeters to several meters. The surface between the blocks is composed of fine-grained material. Accumulation of some fine-grained material behind blocks indicates wind deposition of dust and sand downwind of obstacles. The large block on the horizon is about 4 meters (13 feet) wide. Distance across the horizon is about 34 meters (110 feet). http://photojournal.jpl.nasa.gov/catalog/PIA00385
LEGO® Bricks as Building Blocks for Centimeter-Scale Biological Environments: The Case of Plants
Lind, Kara R.; Sizmur, Tom; Benomar, Saida; Miller, Anthony; Cademartiri, Ludovico
2014-01-01
LEGO bricks are commercially available interlocking pieces of plastic that are conventionally used as toys. We describe their use to build engineered environments for cm-scale biological systems, in particular plant roots. Specifically, we take advantage of the unique modularity of these building blocks to create inexpensive, transparent, reconfigurable, and highly scalable environments for plant growth in which structural obstacles and chemical gradients can be precisely engineered to mimic soil. PMID:24963716
LEGO® bricks as building blocks for centimeter-scale biological environments: the case of plants.
Lind, Kara R; Sizmur, Tom; Benomar, Saida; Miller, Anthony; Cademartiri, Ludovico
2014-01-01
LEGO bricks are commercially available interlocking pieces of plastic that are conventionally used as toys. We describe their use to build engineered environments for cm-scale biological systems, in particular plant roots. Specifically, we take advantage of the unique modularity of these building blocks to create inexpensive, transparent, reconfigurable, and highly scalable environments for plant growth in which structural obstacles and chemical gradients can be precisely engineered to mimic soil.
Remote operation of the Black Knight unmanned ground combat vehicle
NASA Astrophysics Data System (ADS)
Valois, Jean-Sebastien; Herman, Herman; Bares, John; Rice, David P.
2008-04-01
The Black Knight is a 12-ton, C-130 deployable Unmanned Ground Combat Vehicle (UGCV). It was developed to demonstrate how unmanned vehicles can be integrated into a mechanized military force to increase combat capability while protecting Soldiers in a full spectrum of battlefield scenarios. The Black Knight is used in military operational tests that allow Soldiers to develop the necessary techniques, tactics, and procedures to operate a large unmanned vehicle within a mechanized military force. It can be safely controlled by Soldiers from inside a manned fighting vehicle, such as the Bradley Fighting Vehicle. Black Knight control modes include path tracking, guarded teleoperation, and fully autonomous movement. Its state-of-the-art Autonomous Navigation Module (ANM) includes terrain-mapping sensors for route planning, terrain classification, and obstacle avoidance. In guarded teleoperation mode, the ANM data, together with automotive dials and gages, are used to generate video overlays that assist the operator for both day and night driving performance. Remote operation of various sensors also allows Soldiers to perform effective target location and tracking. This document covers Black Knight's system architecture and includes implementation overviews of the various operation modes. We conclude with lessons learned and development goals for the Black Knight UGCV.
This randomized phase II trial studies how well afimoxifene works in reducing the risk of breast cancer in women with mammographically dense breast. Estrogen can cause the growth of breast cancer cells. Hormone therapy using afimoxifene may fight breast cancer by blocking the use of estrogen by the tumor cells. |
A Study on the Saving Method of Plate Jigs in Hull Block Butt Welding
NASA Astrophysics Data System (ADS)
Ko, Dae-Eun
2017-11-01
A large amount of plate jigs is used for alignment of welding line and control of welding deformations in hull block assembly stage. Besides material cost, the huge working man-hours required for working process of plate jigs is one of the obstacles in productivity growth of shipyard. In this study, analysis method was proposed to simulate the welding deformations of block butt joint with plate jigs setting. Using the proposed analysis method, an example simulation was performed for actual panel block joint to investigate the saving method of plate jigs. Results show that it is possible to achieve two objectives of quality accuracy of the hull block and saving the plate jig usage at the same time by deploying the plate jigs at the right places. And the proposed analysis method can be used in establishing guidelines for the proper use of plate jigs in block assembly stage.
FBCOT: a fast block coding option for JPEG 2000
NASA Astrophysics Data System (ADS)
Taubman, David; Naman, Aous; Mathew, Reji
2017-09-01
Based on the EBCOT algorithm, JPEG 2000 finds application in many fields, including high performance scientific, geospatial and video coding applications. Beyond digital cinema, JPEG 2000 is also attractive for low-latency video communications. The main obstacle for some of these applications is the relatively high computational complexity of the block coder, especially at high bit-rates. This paper proposes a drop-in replacement for the JPEG 2000 block coding algorithm, achieving much higher encoding and decoding throughputs, with only modest loss in coding efficiency (typically < 0.5dB). The algorithm provides only limited quality/SNR scalability, but offers truly reversible transcoding to/from any standard JPEG 2000 block bit-stream. The proposed FAST block coder can be used with EBCOT's post-compression RD-optimization methodology, allowing a target compressed bit-rate to be achieved even at low latencies, leading to the name FBCOT (Fast Block Coding with Optimized Truncation).
2010-01-01
Background Sexual selection theory predicts that females, being the limiting sex, invest less in courtship signals than males. However, when chemical signals are involved it is often the female that initiates mating by producing stimuli that inform about sex and/or receptivity. This apparent contradiction has been discussed in the literature as 'the female pheromone fallacy'. Because the release of chemical stimuli may not have evolved to elicit the male's courtship response, whether these female stimuli represent signals remains an open question. Using techniques to visualise and block release of urine, we studied the role of urine signals during fighting and mating interactions of crayfish (Pacifastacus leniusculus). Test individuals were blindfolded to exclude visual disturbance from dye release and artificial urine introduction. Results Staged female-male pairings during the reproductive season often resulted in male mating attempts. Blocking female urine release in such pairings prevented any male courtship behaviour. Artificial introduction of female urine re-established male mating attempts. Urine visualisation showed that female urine release coincides with aggressive behaviours but not with female submissive behaviour in reproductive interactions as well as in intersexual and intrasexual fights. In reproductive interactions, females predominately released urine during precopulatory aggression; males subsequently released significantly less urine during mating than in fights. Conclusions Urine-blocking experiments demonstrate that female urine contains sex-specific components that elicit male mating behaviour. The coincidence of chemical signalling and aggressive behaviour in both females and males suggests that urine release has evolved as an aggressive signal in both sexes of crayfish. By limiting urine release to aggressive behaviours in reproductive interactions females challenge their potential mating partners at the same time as they trigger a sexual response. These double messages should favour stronger males that are able to overcome the resistance of the female. We conclude that the difference between the sexes in disclosing urine-borne information reflects their conflicting interests in reproduction. Males discontinue aggressive urine signalling in order to increase their chances of mating. Females resume urine signalling in connection with aggressive behaviour, potentially repelling low quality or sexually inactive males while favouring reproduction with high quality males. PMID:20353555
How Obstacles Perturb Population Fronts and Alter Their Genetic Structure.
Möbius, Wolfram; Murray, Andrew W; Nelson, David R
2015-12-01
As populations spread into new territory, environmental heterogeneities can shape the population front and genetic composition. We focus here on the effects of an important building block of heterogeneous environments, isolated obstacles. With a combination of experiments, theory, and simulation, we show how isolated obstacles both create long-lived distortions of the front shape and amplify the effect of genetic drift. A system of bacteriophage T7 spreading on a spatially heterogeneous Escherichia coli lawn serves as an experimental model system to study population expansions. Using an inkjet printer, we create well-defined replicates of the lawn and quantitatively study the population expansion of phage T7. The transient perturbations of the population front found in the experiments are well described by a model in which the front moves with constant speed. Independent of the precise details of the expansion, we show that obstacles create a kink in the front that persists over large distances and is insensitive to the details of the obstacle's shape. The small deviations between experimental findings and the predictions of the constant speed model can be understood with a more general reaction-diffusion model, which reduces to the constant speed model when the obstacle size is large compared to the front width. Using this framework, we demonstrate that frontier genotypes just grazing the side of an isolated obstacle increase in abundance, a phenomenon we call 'geometry-enhanced genetic drift', complementary to the founder effect associated with spatial bottlenecks. Bacterial range expansions around nutrient-poor barriers and stochastic simulations confirm this prediction. The effect of the obstacle on the genealogy of individuals at the front is characterized by simulations and rationalized using the constant speed model. Lastly, we consider the effect of two obstacles on front shape and genetic composition of the population illuminating the effects expected from complex environments with many obstacles.
Khalil, Georges E
2012-08-01
Despite the improved survival rate for patients with cancer in the United States, there is a need for successful intervention programs that can raise awareness about cancer risks among healthy young adults. This research experimentally examines how conflict in a digital game called "Re-Mission™" (HopeLab, Redwood City, CA) may influence young adults' perception of cancer risk, their motivation to get protected from cancer, and their intention to seek cancer-related information from their doctors. "Re-Mission" is a game in which players control a nanorobot that goes inside patients' virtual bodies to fight cancer cells. Two days after completing a baseline survey, participants (n=48) played "Re-Mission" at either low or high conflict (i.e., low or high level of obstacles and challenges in the game). Then, participants completed a post-experience survey. Participants in the high conflict condition experienced an increase in perceived susceptibility to and severity of cancer. They also increased their intentions to seek information by talking with a physician. Conflict also blocked any decrease in protective motivation. This study suggests that by virtually experiencing the consequences of cancer cell behavior, young adult players of "Re-Mission" increased in perception of cancer risks, protective motivation, and intentions to seek cancer-related information. In practice, health interventions should not only disseminate visual information about cancer, but also give the public the opportunity to virtually experience the consequences of cancer in order to understand the risks and become motivated to get protected. Implications for future research are also discussed.
Overcoming Resistance to Change
ERIC Educational Resources Information Center
Hull, Ted H.; Balka, Don S.; Miles, Ruth Harbin
2010-01-01
Resistance to change is a major obstacle in developing and implementing effective instructional programs, yet it is rarely considered, discussed, or addressed. The school leaders who are responsible for improvement frequently feel that their efforts are being blocked or thwarted. For the most part, they are correct, but they may not realize that…
Fire Fighting Task Force (FIRE)
1989-04-01
and fdenify by block number) ~’This study is part of ~a contining effort to develop soldier data and performance algorithms (pergorithus) needed to...similar to combat, results will be useful in developing algorithms and data for use in US Army Concepts Analysis Agency (CAA) combat models. THE...dimensions. The US Army Concepts Analysis Agency (CAA) is committed to adding the soldier variables and algorithms that are necessary to fully represent
How Obstacles Perturb Population Fronts and Alter Their Genetic Structure
Möbius, Wolfram; Murray, Andrew W.; Nelson, David R.
2015-01-01
As populations spread into new territory, environmental heterogeneities can shape the population front and genetic composition. We focus here on the effects of an important building block of heterogeneous environments, isolated obstacles. With a combination of experiments, theory, and simulation, we show how isolated obstacles both create long-lived distortions of the front shape and amplify the effect of genetic drift. A system of bacteriophage T7 spreading on a spatially heterogeneous Escherichia coli lawn serves as an experimental model system to study population expansions. Using an inkjet printer, we create well-defined replicates of the lawn and quantitatively study the population expansion of phage T7. The transient perturbations of the population front found in the experiments are well described by a model in which the front moves with constant speed. Independent of the precise details of the expansion, we show that obstacles create a kink in the front that persists over large distances and is insensitive to the details of the obstacle’s shape. The small deviations between experimental findings and the predictions of the constant speed model can be understood with a more general reaction-diffusion model, which reduces to the constant speed model when the obstacle size is large compared to the front width. Using this framework, we demonstrate that frontier genotypes just grazing the side of an isolated obstacle increase in abundance, a phenomenon we call ‘geometry-enhanced genetic drift’, complementary to the founder effect associated with spatial bottlenecks. Bacterial range expansions around nutrient-poor barriers and stochastic simulations confirm this prediction. The effect of the obstacle on the genealogy of individuals at the front is characterized by simulations and rationalized using the constant speed model. Lastly, we consider the effect of two obstacles on front shape and genetic composition of the population illuminating the effects expected from complex environments with many obstacles. PMID:26696601
Flight test of a low-altitude helicopter guidance system with obstacle avoidance capability
NASA Technical Reports Server (NTRS)
Zelenka, Richard E.; Clark, Raymond F.; Branigan, Robert G.
1995-01-01
Military aircraft regularly conduct missions that include low-atltitude, near-terrain flight in order to increase covertness and payload effectiveness. Civilian applications include airborne fire fighting, police surveillance, search and rescue, and helicopter emergency medical service. Several fixed-wing aircraft now employ terrain elevation maps and forward-pointed radars to achieve automated terrain following or terrain avoidance flight. Similar systems specialized to helicopters and their flight regime have not received as much attention. A helicopter guidance system relying on digitized terrain elevation maps has been developed that employs airborne navigation, mission requirements, aircraft performance limits, and radar altimeter returns to generate a valley-seeking, low-altitude trajectory between waypoints. The guidance trajectory is symbolically presented to the pilot on a helmet mounted display. This system has been flight tested to 150 ft (45.7 m) above ground level altitude at 80 kts, and is primarily limited by the ability of the pilot to perform manual detection and avoidance of unmapped hazards. In this study, a wide field of view laser radar sensor has been incorporated into this guidance system to assist the pilot in obstacle detection and avoidance, while expanding the system's operational flight envelope. The results from early flight tests of this system are presented. Low-altitude missions to 100 ft (30.5 m) altitude at 80n kts in the presence of unmapped natural and man-made obstacles were demonstrated while the pilot maintained situational awareness and tracking of the guidance trajectory. Further reductions in altitude are expected with continued flight testing.
ERIC Educational Resources Information Center
Lesh, Seymour; And Others
This demonstration aims at eliminating major obstacles blocking career advancement of human service paraprofessionals. It seeks to develop new options for upgrading workers in four occupations: addiction services, child development, occupational therapy, and teaching. The policies and practices of educational institutions, employers, unions,…
Mostafavi, Ehsan; Haghdoost, Aliakbar; Mirzazadeh, Ali; Riedner, Gabriele; Weis, Peter; Kloss, Kristina; Zolala, Farzaneh
2014-03-01
This study aims to introduce the knowledge hub (KH) as an initiative to facilitate transformation of knowledge into practice and to highlight the activity and limitations with this new policy. The study was conducted through a review of articles; expert views in this field were sought for further information. Regional human immunodeficiency virus (HIV) KHs were developed by the World Health Organization and GTZ. A series of activities including capacity building, development of training models, technical assistance, and application of studies are provided through these hubs. However, financial limitations are the main obstacle in achieving these aims. This piece of work introduces these HIV hubs in order to help countries, particularly developing countries, provide the support needed to fight the progression of HIV.
Introduction of frictional and turning function for pedestrian outflow with an obstacle.
Yanagisawa, Daichi; Kimura, Ayako; Tomoeda, Akiyasu; Nishi, Ryosuke; Suma, Yushi; Ohtsuka, Kazumichi; Nishinari, Katsuhiro
2009-09-01
In this paper, two important factors which affect the pedestrian outflow at a bottleneck significantly are studied in detail to analyze the effect of an obstacle setup in front of an exit. One is a conflict at an exit when pedestrians evacuate from a room. We use floor field model for simulating such behavior, which is a well-studied pedestrian model using cellular automata. The conflicts have been taken into account by the friction parameter. However, the friction parameter so far is a constant and does not depend on the number of the pedestrians conflicting at the same time. Thus, we have improved the friction parameter by the frictional function, which is a function of the number of the pedestrians involved in the conflict. Second, we have presented the cost of turning of pedestrians at the exit. Since pedestrians have inertia, their walking speeds decrease when they turn and the pedestrian outflow decreases. The validity of the extended model, which includes the frictional function and the turning function, is supported by the comparison of a mean-field theory and real experiments. We have observed that the pedestrian flow increases when we put an obstacle in front of an exit in our real experiments. The analytical results clearly explains the mechanism of the effect of the obstacle, i.e., the obstacle blocks pedestrians moving to the exit and decreases the average number of pedestrians involved in the conflict. We have also found that an obstacle works more effectively when we shift it from the center since pedestrians go through the exit with less turning.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhu, N; Najafi, M; Hancock, S
Purpose: Robust matching of ultrasound images is a challenging problem as images of the same anatomy often present non-trivial differences. This poses an obstacle for ultrasound guidance in radiotherapy. Thus our objective is to overcome this obstacle by designing and evaluating an image blocks matching framework based on a two channel deep convolutional neural network. Methods: We extend to 3D an algorithmic structure previously introduced for 2D image feature learning [1]. To obtain the similarity between two 3D image blocks A and B, the 3D image blocks are divided into 2D patches Ai and Bi. The similarity is then calculatedmore » as the average similarity score of Ai and Bi. The neural network was then trained with public non-medical image pairs, and subsequently evaluated on ultrasound image blocks for the following scenarios: (S1) same image blocks with/without shifts (A and A-shift-x); (S2) non-related random block pairs; (S3) ground truth registration matched pairs of different ultrasound images with/without shifts (A-i and A-reg-i-shift-x). Results: For S1 the similarity scores of A and A-shift-x were 32.63, 18.38, 12.95, 9.23, 2.15 and 0.43 for x=ranging from 0 mm to 10 mm in 2 mm increments. For S2 the average similarity score for non-related block pairs was −1.15. For S3 the average similarity score of ground truth registration matched blocks A-i and A-reg-i-shift-0 (1≤i≤5) was 12.37. After translating A-reg-i-shift-0 by 0 mm, 2 mm, 4 mm, 6 mm, 8 mm, and 10 mm, the average similarity scores of A-i and A-reg-i-shift-x were 11.04, 8.42, 4.56, 2.27, and 0.29 respectively. Conclusion: The proposed method correctly assigns highest similarity to corresponding 3D ultrasound image blocks despite differences in image content and thus can form the basis for ultrasound image registration and tracking.[1] Zagoruyko, Komodakis, “Learning to compare image patches via convolutional neural networks', IEEE CVPR 2015,pp.4353–4361.« less
Reflexive obstacle avoidance for kinematically-redundant manipulators
NASA Technical Reports Server (NTRS)
Karlen, James P.; Thompson, Jack M., Jr.; Farrell, James D.; Vold, Havard I.
1989-01-01
Dexterous telerobots incorporating 17 or more degrees of freedom operating under coordinated, sensor-driven computer control will play important roles in future space operations. They will also be used on Earth in assignments like fire fighting, construction and battlefield support. A real time, reflexive obstacle avoidance system, seen as a functional requirement for such massively redundant manipulators, was developed using arm-mounted proximity sensors to control manipulator pose. The project involved a review and analysis of alternative proximity sensor technologies for space applications, the development of a general-purpose algorithm for synthesizing sensor inputs, and the implementation of a prototypical system for demonstration and testing. A 7 degree of freedom Robotics Research K-2107HR manipulator was outfitted with ultrasonic proximity sensors as a testbed, and Robotics Research's standard redundant motion control algorithm was modified such that an object detected by sensor arrays located at the elbow effectively applies a force to the manipulator elbow, normal to the axis. The arm is repelled by objects detected by the sensors, causing the robot to steer around objects in the workspace automatically while continuing to move its tool along the commanded path without interruption. The mathematical approach formulated for synthesizing sensor inputs can be employed for redundant robots of any kinematic configuration.
1980-01-01
SUPPLEMENTARY NOTES Is. KEY WORDS (Continue on reverse ede If neceseay id Identify by block number) Carbon Monoxide (CO) Computer Program Carboxyhemoglobin ...several researchers, which predicts the instantaneous amount of carboxyhemoglobin (COHb) in the blood of a person based upon the amount of carbon monoxide...developed from an empirical equation (derived from reference I and detailed in reference 3) which predicts the amount of carboxyhemoglobin (COHb) in
NASA Astrophysics Data System (ADS)
Aubé, M.; Simoneau, A.
2018-05-01
Illumina is one of the most physically detailed artificial night sky brightness model to date. It has been in continuous development since 2005 [1]. In 2016-17, many improvements were made to the Illumina code including an overhead cloud scheme, an improved blocking scheme for subgrid obstacles (trees and buildings), and most importantly, a full hyperspectral modeling approach. Code optimization resulted in significant reduction in execution time enabling users to run the model on standard personal computers for some applications. After describing the new schemes introduced in the model, we give some examples of applications for a peri-urban and a rural site both located inside the International Dark Sky reserve of Mont-Mégantic (QC, Canada).
Reader's Block: A Systematic Review of Barriers to Adoption, Access and Use in E-Book User Studies
ERIC Educational Resources Information Center
Girard, Adam
2014-01-01
Introduction: This review of barriers to e-book use systematically identifies obstacles to engaging reading experiences. Through the use of an analytical framework, the users being studied, study setting, and methods used in previous work are described in order to identify promising areas for future research. Method: The method used is a…
The Democratic Revolution. Proceedings of a Conference (Washington, D.C., May 1-2, 1989).
ERIC Educational Resources Information Center
National Endowment for Democracy, Washington, DC.
Divided into seven sections, the presentations contained in these proceedings give an international perspective on the growth of democracy in the world, and the many obstacles that might inhibit it. The first section, on Eastern Europe and the Soviet Union contains papers from four East Block scholars who discuss the rise of democracy in communist…
Complexity, Networking, & Effects-Based Approaches to Operations
2006-06-01
b. ABSTRACT unclassified c . THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 This book is dedicated to the ...Civil War. Vol. 14. Alexandria: Time-Life. 2001. p. 149. 27 Eliot, T.S. “ The Love Song of J. Alfred Prufrock.” The Complete Poems and Plays (1909...1968. pp. 501-510. 31 Krulak, GEN Charles C ., USMC. “ The Three Block War: Fighting in Urban Areas.” Vital Speeches of the Day. Vol 64, Iss. 5. New
NCI Scientists Solve Structure of Protein that Enables MERS Virus to Spread | Poster
Scientists at the Frederick National Lab have produced three crystal structures that reveal a specific part of a protein that can be targeted to fight the Middle East respiratory syndrome coronavirus (MERS-CoV), which causes an emerging viral respiratory illness. Senior Investigator David Waugh, Ph.D., Macromolecular Crystallography Laboratory, has solved the structure of an enzyme known as the 3C-like protease (3CLpro), which, if blocked, can prevent the virus from replicating...
Developing close combat behaviors for simulated soldiers using genetic programming techniques.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pryor, Richard J.; Schaller, Mark J.
2003-10-01
Genetic programming is a powerful methodology for automatically producing solutions to problems in a variety of domains. It has been used successfully to develop behaviors for RoboCup soccer players and simple combat agents. We will attempt to use genetic programming to solve a problem in the domain of strategic combat, keeping in mind the end goal of developing sophisticated behaviors for compound defense and infiltration. The simplified problem at hand is that of two armed agents in a small room, containing obstacles, fighting against each other for survival. The base case and three changes are considered: a memory of positionsmore » using stacks, context-dependent genetic programming, and strongly typed genetic programming. Our work demonstrates slight improvements from the first two techniques, and no significant improvement from the last.« less
Interferon lambda: opportunities, risks, and uncertainties in the fight against HCV.
Laidlaw, Stephen M; Dustin, Lynn B
2014-01-01
Innate immunity is key to the fight against the daily onslaught from viruses that our bodies are subjected to. Essential to this response are the interferons (IFNs) that prime our cells to block viral pathogens. Recent evidence suggests that the Type III (λ) IFNs are intimately associated with the immune response to hepatitis C virus (HCV) infection. Genome-wide association studies have identified polymorphisms within the IFN-λ gene locus that correlate with response to IFNα-based antiviral therapy and with spontaneous clearance of HCV infection. The mechanisms for these correlations are incompletely understood. Restricted expression of the IFN-λ receptor, and the ability of IFN-λ to induce IFN-stimulated genes in HCV-infected cells, suggest potential roles for IFN-λ in HCV therapy even in this era of directly acting antivirals. This review summarizes our current understanding of the IFN-λ family and the role of λ IFNs in the natural history of HCV infection.
Mobilizing for a war on the home front against sugar-related morbidity and mortality.
Schillinger, Dean; Kahn, James G
2017-01-01
In Israel today, there are 420,200 Israelis diagnosed with diabetes, and every year, Israelis sustain thousands of diabetes-related deaths and tens of thousands of diabetes-related amputations. As such, in Israel, as in much of the world, there is a silent and deadly public health war against obesity and diabetes taking place on the home front -- one in which clinicians, patients, and families fight thousands of life- and limb-threatening battles daily, involving preventable heart disease, diabetes, strokes and amputations. Yet the global clinical and scientific communities, indeed society at large, have barely begun to mobilize. Fighting this war requires confronting and altering "obesogenic" and "diabetogenic" economic and social factors, including food and beverage marketing and pricing that push diets engorged with processed sugars. Ginsberg, in a study recently published in IJHPR, contributes to our understanding of the combined sugar-related health burdens in Israel, producing an epidemiology and health economics study that estimates the health burdens of obesity, overweight, and dental caries in Israel today. He projects the reductions resulting from that portion of disease burden and associated costs if sugar consumption declined to 10 or 5% of daily caloric consumption as a result of multifaceted public health interventions. Projected over 70 years, these reductions in sugar consumption would prevent 16,590 and 34,580 deaths, respectively. These numbers of Israeli deaths averted are similar to, or exceed, the total resulting from armed conflict or terrorism over the past 70 years. While overconsumption of sugar is only one of many factors that drive cardio-metabolic disease, the study by Ginsberg suggests a path through which we can overcome the numerous internal and external obstacles that societies face in making a public policy commitment to fight the warm on the home front: promoting health by reducing added sugar exposure.
Obstacle Detection using Binocular Stereo Vision in Trajectory Planning for Quadcopter Navigation
NASA Astrophysics Data System (ADS)
Bugayong, Albert; Ramos, Manuel, Jr.
2018-02-01
Quadcopters are one of the most versatile unmanned aerial vehicles due to its vertical take-off and landing as well as hovering capabilities. This research uses the Sum of Absolute Differences (SAD) block matching algorithm for stereo vision. A complementary filter was used in sensor fusion to combine obtained quadcopter orientation data from the accelerometer and the gyroscope. PID control was implemented for the motor control and VFH+ algorithm was implemented for trajectory planning. Results show that the quadcopter was able to consistently actuate itself in the roll, yaw and z-axis during obstacle avoidance but was however found to be inconsistent in the pitch axis during forward and backward maneuvers due to the significant noise present in the pitch axis angle outputs compared to the roll and yaw axes.
More, Vijay R; Campos, Christopher R; Evans, Rebecca A; Oliver, Keith D; Chan, Gary NY; Miller, David S
2016-01-01
Lipid sensor peroxisome proliferator-activated receptor alpha (PPAR-α) is the master regulator of lipid metabolism. Dietary release of endogenous free fatty acids, fibrates, and certain persistent environmental pollutants, e.g. perfluoroalkyl fire-fighting foam components, are peroxisome proliferator-activated receptor alpha ligands. Here, we define a role for peroxisome proliferator-activated receptor alpha in regulating the expression of three ATP-driven drug efflux transporters at the rat and mouse blood–brain barriers: P-glycoprotein (Abcb1), breast cancer resistance protein (Bcrp/Abcg2), and multidrug resistance-associated protein 2 (Mrp2/Abcc2). Exposing isolated rat brain capillaries to linoleic acid, clofibrate, or PKAs increased the transport activity and protein expression of the three ABC transporters. These effects were blocked by the PPAR-α antagonist, GW6471. Dosing rats with 20 mg/kg or 200 mg/kg of clofibrate decreased the brain accumulation of the P-glycoprotein substrate, verapamil, by 50% (in situ brain perfusion; effects blocked by GW6471) and increased P-glycoprotein expression and activity in capillaries ex vivo. Fasting C57Bl/6 wild-type mice for 24 h increased both serum lipids and brain capillary P-glycoprotein transport activity. Fasting did not alter P-glycoprotein activity in PPAR-α knockout mice. These results indicate that hyperlipidemia, lipid-lowering fibrates and exposure to certain fire-fighting foam components activate blood–brain barrier peroxisome proliferator-activated receptor alpha, increase drug efflux transporter expression and reduce drug delivery to the brain. PMID:27193034
Rauchfuss, Knut; Schmolze, Bianca
2008-01-01
Case studies show that traumatized refugees, who are survivors of serious human rights violations, suffer from persisting impunity in their home countries. Ongoing impunity--the inability to overcome the legal protection of the perpetrators assured by impunity laws, incomplete truthfinding, missing integral reparation and a lack of the necessary acknowledgement by society--represents an important obstacle for the recovery of survivors of serious human rights violations. There are reports describing that a high percentage of survivors shows an elevated mental vulnerability caused by impunity. Mental health problems resulting from traumatic experiences can persist or be reactivated by certain events. In particular, family members of the forcibly disappeared suffer from an incomplete mourning due to the uncertain fate of their beloved ones. The ongoing search for the forcibly disappeared under an atmosphere of impunity puts family members under high risk of retraumatization. Studies from other continents also prove that impunity severely affects mental health. Due to the global character of impunity there can be only little evidence about a positive impact of justice on mental health. Nevertheless, a few examples, in particular from Latin America, show that the combined implementation of memory, truth and justice can have a healing impact on those who suffer from trauma. They demonstrate that the fight against impunity is not only a legitimate moral struggle for human rights, but also a basic need for the sustainable recovery of survivors.
Multi-stream face recognition for crime-fighting
NASA Astrophysics Data System (ADS)
Jassim, Sabah A.; Sellahewa, Harin
2007-04-01
Automatic face recognition (AFR) is a challenging task that is increasingly becoming the preferred biometric trait for identification and has the potential of becoming an essential tool in the fight against crime and terrorism. Closed-circuit television (CCTV) cameras have increasingly been used over the last few years for surveillance in public places such as airports, train stations and shopping centers. They are used to detect and prevent crime, shoplifting, public disorder and terrorism. The work of law-enforcing and intelligence agencies is becoming more reliant on the use of databases of biometric data for large section of the population. Face is one of the most natural biometric traits that can be used for identification and surveillance. However, variations in lighting conditions, facial expressions, face size and pose are a great obstacle to AFR. This paper is concerned with using waveletbased face recognition schemes in the presence of variations of expressions and illumination. In particular, we will investigate the use of a combination of wavelet frequency channels for a multi-stream face recognition using various wavelet subbands as different face signal streams. The proposed schemes extend our recently developed face veri.cation scheme for implementation on mobile devices. We shall present experimental results on the performance of our proposed schemes for a number of face databases including a new AV database recorded on a PDA. By analyzing the various experimental data, we shall demonstrate that the multi-stream approach is robust against variations in illumination and facial expressions than the previous single-stream approach.
Achieving Cross-Domain Synergy: Overcoming Service Barriers to Joint Force 2020
2014-06-13
culture. It is my hope that this thesis will be of value to the Joint community by contributing to their understanding of inter-service cultural...Identify leadership implications. 8. Identify metrics, measures, and milestones to maintain accountability. 9. Identify a communication strategy...Under- communicating the vision 5. Permitting obstacles to block the vision 6. Failing to create short-term wins 7. Declaring victory too soon 8
Navigating the Information Revolution: Choices for Laggard Countries
2007-01-01
ways to satisfy this demand. Culture, religion , 3 Wood block printing or xylography was first developed in China, movable type was later developed...in Korea and China (Kang 2000). Religion was the key obstacle in the Islamic empire (Dator 2004) while political instability (BBC 2003) and...illiteracy (Deveneaux 1976) were the culprits in Africa. The history of the printing press suggests that market size, culture, religion , governance and
Multi-hop path tracing of mobile robot with multi-range image
NASA Astrophysics Data System (ADS)
Choudhury, Ramakanta; Samal, Chandrakanta; Choudhury, Umakanta
2010-02-01
It is well known that image processing depends heavily upon image representation technique . This paper intends to find out the optimal path of mobile robots for a specified area where obstacles are predefined as well as modified. Here the optimal path is represented by using the Quad tree method. Since there has been rising interest in the use of quad tree, we have tried to use the successive subdivision of images into quadrants from which the quad tree is developed. In the quad tree, obstacles-free area and the partial filled area are represented with different notations. After development of quad tree the algorithm is used to find the optimal path by employing neighbor finding technique, with a view to move the robot from the source to destination. The algorithm, here , permeates through the entire tree, and tries to locate the common ancestor for computation. The computation and the algorithm, aim at easing the ability of the robot to trace the optimal path with the help of adjacencies between the neighboring nodes as well as determining such adjacencies in the horizontal, vertical and diagonal directions. In this paper efforts have been made to determine the movement of the adjacent block in the quad tree and to detect the transition between the blocks equal size and finally generate the result.
Measurement of stimulated Hawking emission in an analogue system.
Weinfurtner, Silke; Tedford, Edmund W; Penrice, Matthew C J; Unruh, William G; Lawrence, Gregory A
2011-01-14
Hawking argued that black holes emit thermal radiation via a quantum spontaneous emission. To address this issue experimentally, we utilize the analogy between the propagation of fields around black holes and surface waves on moving water. By placing a streamlined obstacle into an open channel flow we create a region of high velocity over the obstacle that can include surface wave horizons. Long waves propagating upstream towards this region are blocked and converted into short (deep-water) waves. This is the analogue of the stimulated emission by a white hole (the time inverse of a black hole), and our measurements of the amplitudes of the converted waves demonstrate the thermal nature of the conversion process for this system. Given the close relationship between stimulated and spontaneous emission, our findings attest to the generality of the Hawking process.
Emergent oscillations assist obstacle negotiation during ant cooperative transport.
Gelblum, Aviram; Pinkoviezky, Itai; Fonio, Ehud; Gov, Nir S; Feinerman, Ofer
2016-12-20
Collective motion by animal groups is affected by internal interactions, external constraints, and the influx of information. A quantitative understanding of how these different factors give rise to different modes of collective motion is, at present, lacking. Here, we study how ants that cooperatively transport a large food item react to an obstacle blocking their path. Combining experiments with a statistical physics model of mechanically coupled active agents, we show that the constraint induces a deterministic collective oscillatory mode that facilitates obstacle circumvention. We provide direct experimental evidence, backed by theory, that this motion is an emergent group effect that does not require any behavioral changes at the individual level. We trace these relaxation oscillations to the interplay between two forces; informed ants pull the load toward the nest whereas uninformed ants contribute to the motion's persistence along the tangential direction. The model's predictions that oscillations appear above a critical system size, that the group can spontaneously transition into its ordered phase, and that the system can exhibit complete rotations are all verified experimentally. We expect that similar oscillatory modes emerge in collective motion scenarios where the structure of the environment imposes conflicts between individually held information and the group's tendency for cohesiveness.
Doing More with Less: Cost-effective, Compact Particle Accelerators (489th Brookhaven Lecture)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Trbojevic, Dejan
2013-10-22
Replace a 135-ton magnet used for cancer-fighting particle therapies with a magnet that weighs only two tons? Such a swap is becoming possible thanks to new particle accelerator advances being developed by researchers at Brookhaven Lab. With an approach that combines techniques used by synchrotron accelerators with the ability to accept more energy, these new technologies could be used for more than fighting cancer. They could also decrease the lifecycle of byproducts from nuclear power plants and reduce costs for eRHIC—a proposed electron-ion collider for Brookhaven Lab that researchers from around the world would use to explore the glue thatmore » holds together the universe’s most basic building blocks and explore the proton-spin puzzle. During this lecture, Dr. Trbojevic provides an overview of accelerator technologies and techniques—particularly a non-scaling, fixed-focused alternating gradient—to focus particle beams using fewer, smaller magnets. He discusses how these technologies will benefit eRHIC and other applications, including particle therapies being developed to combat cancer.« less
3C.07: ARE THE PHYSICIANS RELUCTANT TO PRACTICE TELEMEDICINE IN HYPERTENSION?
Sublet, M Lopez; Courand, P Y; Bally, S; Krummel, T; Dimitrov, Y; Brucker, M; Coz, S Regnier-Le; Dourmap-Collas, C; Mourad, J J; Steichen, O; Ott, J; Barone-Rochette, G; Bogetto-Graham, L; Rossignol, P; Barber-Chamoux, N; Le Jeune, S; Vautrin, E; Agnoletti, D; Baguet, S; Sosner, P
2015-06-01
The high number of patients with uncontrolled hypertension is still a public health pattern. The e-health contains all electronic health services used in order to improve communication between all the different actors. In arterial hypertension, few data exists on the possibilities: 1/ for patients to easily e-transfer their results of home blood pressure measurement (HBPM); 2/ for practitioners to receive and assess these HBPM results. Furthermore, physician's reluctance is often reported as a constraint for telemedicine development. Thus, we aimed to collect data on technical equipment of physicians, and on their expectations about this new way of relationship. 57 physicians, hypertension specialists (36 ± 8 years old, 56% men, mostly (88%) hospital practitioners) completed a self-administered questionnaire. The prevalence of technical equipment is summarized in Table 1. 77.1% of physicians thought that telemedicine could improve the control of hypertension, 29.8% thought they could provide less frequent consultations to their patients and 24.5 % that HBPM information would contribute to the fight against inertia. 83.2% of physicians would agree that HBPM data be transferred to a non- medical staff, a nurse in most cases (59.5%). Finally, while 89.5% of physicians declared they support the development of telemedicine in their daily practice, 100% of them found 3 kinds of "limits" to this exchange method. The main obstacles were: budget (49%), lack of legal frame (43%), medical reluctance (42%), difficulties in accessing or in mastering informatics tool (38.5%), confidentiality (28%), absence of direct benefit (21%), patient reluctance (21%).(Figure is included in full-text article.) : The equipment of physicians in home or mobile devices appears no longer an obstacle for the development of a program dedicated to telemedicine. The majority of medical practitioners working in specialized hypertension department agreed with Internet e-transfer of HBPM data, including paramedics. However, all physicians highlighted various obstacles to its expansion: technical support, lack of legal frame, and financial limits.
Why Adolescents Fight: A Qualitative Study of Youth Perspectives on Fighting and Its Prevention
Shetgiri, Rashmi; Lee, Simon C.; Tillitski, John; Wilson, Connie; Flores, Glenn
2014-01-01
Objective Identify risk factors for fighting, factors that protect against fighting, and strategies to prevent fighting, among adolescents who fight and those uninvolved in fighting. Methods Focus groups were conducted with middle and high-school students, stratified by fighting (fighter/non-fighter) status, race/ethnicity, and gender. Groups were audiotaped, transcribed, and analyzed using margin coding and thematic content analysis. Themes were independently identified by three coders; disagreements were resolved by consensus. Results The 65 participants in the 12 focus groups were 13–17 years old. Reasons for fighting include self-defense, to gain/maintain respect, or due to anger; having goals for the future is protective. Non-fighters state that their parents condone fighting only when physically attacked, and teach adolescents strategies to avoid fighting. Fighters describe mixed messages from parents, and pro-fighting attitudes and modeling of aggressive behavior among some family members. Non-fighters avoid fighting by ignoring insults or walking away. Fighters feel unable to use nonviolent conflict-resolution methods effectively. Peers may instigate or encourage fights. Suggested prevention strategies include anger-management and conflict-resolution programs, relationships with caring adults, and physicians counseling youth about the consequences of fighting. Conclusions Non-fighters use various strategies to avoid fighting, whereas fighters are aware of few alternatives to fighting. Conflicting parental messages about fighting may enhance the likelihood of fighting. Physicians can counsel youth about the negative consequences of fighting. Interventions that teach anger management and conflict resolution, promote adolescent self-efficacy for using non-violent strategies, and address parental attitudes about fighting may be effective in preventing fighting. PMID:25528128
Efficient preparation of large-block-code ancilla states for fault-tolerant quantum computation
NASA Astrophysics Data System (ADS)
Zheng, Yi-Cong; Lai, Ching-Yi; Brun, Todd A.
2018-03-01
Fault-tolerant quantum computation (FTQC) schemes that use multiqubit large block codes can potentially reduce the resource overhead to a great extent. A major obstacle is the requirement for a large number of clean ancilla states of different types without correlated errors inside each block. These ancilla states are usually logical stabilizer states of the data-code blocks, which are generally difficult to prepare if the code size is large. Previously, we have proposed an ancilla distillation protocol for Calderbank-Shor-Steane (CSS) codes by classical error-correcting codes. It was assumed that the quantum gates in the distillation circuit were perfect; however, in reality, noisy quantum gates may introduce correlated errors that are not treatable by the protocol. In this paper, we show that additional postselection by another classical error-detecting code can be applied to remove almost all correlated errors. Consequently, the revised protocol is fully fault tolerant and capable of preparing a large set of stabilizer states sufficient for FTQC using large block codes. At the same time, the yield rate can be boosted from O (t-2) to O (1 ) in practice for an [[n ,k ,d =2 t +1
Nurturing girls: a key to promoting maternal health.
1991-01-01
Mothers should invest in women's health and in the health of the next generation by taking good care of their daughters beginning at birth. Indeed girls who develop healthily, confidently, and is strong are more apt to have a safe motherhood and nurture their own children so they can reach their full potential. Nevertheless many obstacles to this occurring exist. Even though both girls and boys live in poverty, girls encounter the additional obstacle of sexual discrimination. For example, female infants have an elevated natural immunity level to fight off diseases than do male infants, female infant mortality exceeds male infant mortality in Bangladesh, India, and Pakistan. In addition, excessive death rates among small girls occur in some countries of Africa, the Middle East, Asia and South America. Reduced breast feeding, amount of food, immunization coverage, health care, and school enrollment for females contribute to these excessive death rates among females. In fact, if these deprivations do not result in death, they do cause poor health throughout life and greater risk during pregnancy and childbirth. Motherhood drains the already stunted and anemic bodies. For example, malnourished pregnant women, as evidenced by stunting, often have too small or deformed pelvises making it difficult to delivery a child normally. Anemic mothers cannot easily endure hemorrhaging loss during childbirth and abortion. Finally, deprivation influences a girl's mental ability to manage motherhood. Moreover, it reduces self esteem which in turn renders them reluctant to demand improvements in maternal care which would reduce maternal mortality.
Lane, Sarah M; Briffa, Mark
2018-02-20
The ability to mitigate the costs of engaging in a fight will depend on an individual's physiological state. However, the experience of fighting itself may, in turn, affect an individual's state, especially if the fight results in injury. Previous studies have found a correlation between immune state and fighting success, but the causal direction of this relationship remains unclear. Does immune state determine fighting success? Or does fighting itself influence subsequent immune state? Using the beadlet anemone, Actinia equina , we disentangled the cause and effect of this relationship, measuring immune response once pre-fight and twice post-fight. Contrary to previous findings, pre-fight immune response did not predict fighting success, but rather predicted whether an individual used its weapons during the fight. Furthermore, weapon use and contest outcome significantly affected post-fight immune response. Individuals that used their weapons maintained a stable immune response following the fight, whereas those that fought non-injuriously did not. Furthermore, although winners suffered a reduction in immune response similar to that of losers immediately post-fight, winners began to recover pre-fight levels within 24 h. Our findings indicate that immune state can influence strategic fighting decisions and, moreover, that fight outcome and the agonistic behaviours expressed can significantly affect subsequent immunity. © 2018. Published by The Company of Biologists Ltd.
Kaboru, Berthollet Bwira; Falkenberg, Torkel; Ndubani, Phillimon; Höjer, Bengt; Vongo, Rodwell; Brugha, Ruairi; Faxelid, Elisabeth
2006-01-01
Background The World Health Organization's World health report 2006: Working together for health underscores the importance of human resources for health. The shortage of trained health professionals is among the main obstacles to strengthening low-income countries' health systems and to scaling up HIV/AIDS control efforts. Traditional health practitioners are increasingly depicted as key resources to HIV/AIDS prevention and care. An appropriate and effective response to the HIV/AIDS crisis requires reconsideration of the collaboration between traditional and biomedical health providers (THPs and BHPs). The aim of this paper is to explore biomedical and traditional health practitioners' experiences of and attitudes towards collaboration and to identify obstacles and potential opportunities for them to collaborate regarding care for patients with sexually transmitted infections (STIs) and HIV/AIDS. Methods We conducted a cross-sectional study in two Zambian urban sites, using structured questionnaires. We interviewed 152 biomedical health practitioners (BHPs) and 144 traditional health practitioners (THPs) who reported attending to patients with STIs and HIV/AIDS. Results The study showed a very low level of experience of collaboration, predominated by BHPs training THPs (mostly traditional birth attendants) on issues of safe delivery. Intersectoral contacts addressing STIs and HIV/AIDS care issues were less common. However, both groups of providers overwhelmingly acknowledged the potential role of THPs in the fight against HIV/AIDS. Obstacles to collaboration were identified at the policy level in terms of legislation and logistics. Lack of trust in THPs by individual BHPs was also found to inhibit collaboration. Nevertheless, as many as 40% of BHPs expressed an interest in working more closely with THPs. Conclusion There is indication that practitioners from both sectors seem willing to strengthen collaboration with each other. However, there are missed opportunities. The lack of collaborative framework integrating maternal health with STIs and HIV/AIDS care is at odds with the needed comprehensive approach to HIV/AIDS control. Also, considering the current human resources crisis in Zambia, substantial policy commitment is called for to address the legislative obstacles and the stigma reported by THPs and to provide an adequate distribution of roles between all partners, including traditional health practitioners, in the struggle against HIV/AIDS. PMID:16846497
2007-02-01
saponin (Calbiochem, San Diego, CA) in PBS. Results, Significance, Obstacles and Alternative Approaches: We have generated several different fluorescent...1 integrin antibody P4C10 (Life technologies ). We will conjugate the fluorescent probes to these functional blocking antibodies for live cell...characterization of the prostate-specific membrane antigen (PSMA) in tissue extracts and body fluids. Int. J. Cancer. 62:552-558. 1995. 9. Wright GL Jr
2012-01-01
Proton exchange membrane fuel cells ( PEMFCs ), which convert chemical energy to electrical energy through redox reactions, have been developed as...platinum)-based electrocata- lysts, the commercialization of PEMFCs is still limited. Addi- tionally, oxygen reduction and fuel (hydrogen or alcohol) oxi...These are serious obstacles to the extensive adoption of PEMFCs as energy devices.4 An alkaline fuel cell (AFC) uses potassium hydroxide as a liq- uid
Dual behavior of caustic optical beams facing obstacles
NASA Astrophysics Data System (ADS)
Vaveliuk, Pablo; Martínez-Matos, Óscar; Ren, Yu-Xuan; Lu, Rong-De
2017-06-01
A full propagation analysis on both fold-type and cusp-type caustic optical beams under various setups of obstructions is theoretically and experimentally performed. It is demonstrated that the self-healing property of caustic optical beams that include the famous Airy beam is a quite relative property. In fact, fold-type and cusp-type beams cannot only behave as self-healing beams by blocking the main intensity peak, but also behave as self-breaking ones in a nonintuitive manner: by blocking a lateral side of the beam without touching the central intensity peak. The regeneration and rupture processes of caustic beams follow a nonlocal propagation dynamic unlike the other conventional beams. Moreover, deep differences between fold and cusp caustic beams are pointed out once facing certain obstructions. The cusp-caustic beam can be broken down by the obstacle placed in a dark zone outside the caustic region, while the fold-type one remains unaltered. This beam rupture confirms the key role of a hidden propagating field in the shadow region for cusp beams that coexist with the evanescent one. The obtained results cast down the established idea that the Airy beam is a robust self-healing beam since any caustic beam can behave in a dual manner depending on the obstruction location. These facts open up different perspectives for the applications in which the self-healing properties of the beam are relevant.
How Pecten Brazil drilled the Amazon basin
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bleakley, W.B.
1983-09-01
Pecten Brazil overcame numerous obstacles to drill two exploratory wells in the Amazon Basin last year. These included: The threat of low water in normally navigable rivers. Dense jungle growth at both locations. Lack of suitable roads for heavy hauling. Inconvenient distances from supply points. An unusual basalt formation responsible for unique drilling problems. Hundreds of helicopter lifts to move drilling rigs, supplies, and personnel. Pecten contracted with Petrobras, the Brazilian national oil company, to evaluate three blocks in the Amazon jungle, each about 68 miles (110 km) on a side, through seismic study and ultimate drilling. Planning for themore » drilling phase got started on March 17, 1981 with December 1 targeted as spud date for the first well. Actual spud date was November 25, 5 days ahead of schedule, in spite of all obstacles. Pecten has a mid-Amazonas block now under seismic investigation for possible exploratory drilling. Logistics problems in this one provide new difficulties, as the area is extremely wet. Most work is carried on by boat. The company is also looking offshore Bahia, testing the possible extension of the Renconcavo basin. Two wells have already provided good shows of a high pour point oil, with flow rates from 400 to 1,000 b/d. Another area of interest to Pecten is offshore Rio Grande do Norte.« less
Emergent oscillations assist obstacle negotiation during ant cooperative transport
Gelblum, Aviram; Pinkoviezky, Itai; Fonio, Ehud; Gov, Nir S.; Feinerman, Ofer
2016-01-01
Collective motion by animal groups is affected by internal interactions, external constraints, and the influx of information. A quantitative understanding of how these different factors give rise to different modes of collective motion is, at present, lacking. Here, we study how ants that cooperatively transport a large food item react to an obstacle blocking their path. Combining experiments with a statistical physics model of mechanically coupled active agents, we show that the constraint induces a deterministic collective oscillatory mode that facilitates obstacle circumvention. We provide direct experimental evidence, backed by theory, that this motion is an emergent group effect that does not require any behavioral changes at the individual level. We trace these relaxation oscillations to the interplay between two forces; informed ants pull the load toward the nest whereas uninformed ants contribute to the motion’s persistence along the tangential direction. The model’s predictions that oscillations appear above a critical system size, that the group can spontaneously transition into its ordered phase, and that the system can exhibit complete rotations are all verified experimentally. We expect that similar oscillatory modes emerge in collective motion scenarios where the structure of the environment imposes conflicts between individually held information and the group’s tendency for cohesiveness. PMID:27930304
Effect of cane length and swing arc width on drop-off and obstacle detection with the long cane
Kim, Dae Shik; Emerson, Robert Wall; Naghshineh, Koorosh
2017-01-01
A repeated-measures design with block randomization was used for the study, in which 15 adults with visual impairments attempted to detect the drop-offs and obstacles with the canes of different lengths, swinging the cane in different widths (narrow vs wide). Participants detected the drop-offs significantly more reliably with the standard-length cane (79.5% ± 6.5% of the time) than with the extended-length cane (67.6% ± 9.1%), p <.001. The drop-off detection threshold of the standard-length cane (4.1 ± 1.1 cm) was also significantly smaller than that of the extended-length cane (6.5±1.8cm), p <.001. In addition, participants detected drop-offs at a significantly higher percentage when they swung the cane approximately 3 cm beyond the widest part of the body (78.6% ± 7.6%) than when they swung it substantially wider (30 cm; 68.5% ± 8.3%), p <.001. In contrast, neither cane length (p =.074) nor cane swing arc width (p =.185) had a significant effect on obstacle detection performance. The findings of the study may help orientation and mobility specialists recommend appropriate cane length and cane swing arc width to visually impaired cane users. PMID:29276326
Effect of cane length and swing arc width on drop-off and obstacle detection with the long cane.
Kim, Dae Shik; Emerson, Robert Wall; Naghshineh, Koorosh
2017-09-01
A repeated-measures design with block randomization was used for the study, in which 15 adults with visual impairments attempted to detect the drop-offs and obstacles with the canes of different lengths, swinging the cane in different widths (narrow vs wide). Participants detected the drop-offs significantly more reliably with the standard-length cane (79.5% ± 6.5% of the time) than with the extended-length cane (67.6% ± 9.1%), p <.001. The drop-off detection threshold of the standard-length cane (4.1 ± 1.1 cm) was also significantly smaller than that of the extended-length cane (6.5±1.8cm), p <.001. In addition, participants detected drop-offs at a significantly higher percentage when they swung the cane approximately 3 cm beyond the widest part of the body (78.6% ± 7.6%) than when they swung it substantially wider (30 cm; 68.5% ± 8.3%), p <.001. In contrast, neither cane length ( p =.074) nor cane swing arc width ( p =.185) had a significant effect on obstacle detection performance. The findings of the study may help orientation and mobility specialists recommend appropriate cane length and cane swing arc width to visually impaired cane users.
NASA Astrophysics Data System (ADS)
Prasanna Kumar, S. S.; Patnaik, B. S. V.; Ramamurthi, K.
2018-04-01
The mitigation of blast waves propagating in air and interacting with rigid barriers and obstacles is numerically investigated using the mesh-free smoothed particle hydrodynamics method. A novel virtual boundary particle procedure with a skewed gradient wall boundary treatment is applied at the interfaces between air and rigid bodies. This procedure is validated with closed-form solutions for strong and weak shock reflection from rigid surfaces, supersonic flows over a wedge, formation of reflected, transverse, and Mach stem shocks, and also earlier experiments on interaction of a blast wave with concrete blocks. The mitigation of the overpressure and impulse transmitted to the protected structure due to an array of rigid obstacles of different shapes placed in the path of the blast wave is thereafter determined and discussed in the context of the existing experimental and numerical studies. It is shown that blockages having the shape of a right facing triangle or square placed in tandem or staggered provide better mitigation. The influence of the distance between the blockage array and protected structure is assessed, and the incorporation of a gap in the blockages is shown to improve the mitigation. The mechanisms responsible for the attenuation of air blast are identified through the simulations.
Development and Testing of a Two-UAV Communication Relay System.
Li, Boyang; Jiang, Yifan; Sun, Jingxuan; Cai, Lingfeng; Wen, Chih-Yung
2016-10-13
In the development of beyond-line-of-sight (BLOS) Unmanned Aerial Vehicle (UAV) systems, communication between the UAVs and the ground control station (GCS) is of critical importance. The commonly used economical wireless modules are restricted by the short communication range and are easily blocked by obstacles. The use of a communication relay system provides a practical way to solve these problems, improving the performance of UAV communication in BLOS and cross-obstacle operations. In this study, a communication relay system, in which a quadrotor was used to relay radio communication for another quadrotor was developed and tested. First, the UAVs used as the airborne platform were constructed, and the hardware for the communication relay system was selected and built up. Second, a set of software programs and protocol for autonomous mission control, communication relay control, and ground control were developed. Finally, the system was fully integrated into the airborne platform and tested both indoor and in-flight. The Received Signal Strength Indication (RSSI) and noise value in two typical application scenarios were recorded. The test results demonstrated the ability of this system to extend the communication range and build communication over obstacles. This system also shows the feasibility to coordinate multiple UAVs' communication with the same relay structure.
Development and Testing of a Two-UAV Communication Relay System
Li, Boyang; Jiang, Yifan; Sun, Jingxuan; Cai, Lingfeng; Wen, Chih-Yung
2016-01-01
In the development of beyond-line-of-sight (BLOS) Unmanned Aerial Vehicle (UAV) systems, communication between the UAVs and the ground control station (GCS) is of critical importance. The commonly used economical wireless modules are restricted by the short communication range and are easily blocked by obstacles. The use of a communication relay system provides a practical way to solve these problems, improving the performance of UAV communication in BLOS and cross-obstacle operations. In this study, a communication relay system, in which a quadrotor was used to relay radio communication for another quadrotor was developed and tested. First, the UAVs used as the airborne platform were constructed, and the hardware for the communication relay system was selected and built up. Second, a set of software programs and protocol for autonomous mission control, communication relay control, and ground control were developed. Finally, the system was fully integrated into the airborne platform and tested both indoor and in-flight. The Received Signal Strength Indication (RSSI) and noise value in two typical application scenarios were recorded. The test results demonstrated the ability of this system to extend the communication range and build communication over obstacles. This system also shows the feasibility to coordinate multiple UAVs’ communication with the same relay structure. PMID:27754369
RNA interference in the clinic: challenges and future directions
Pecot, Chad V.; Calin, George A.; Coleman, Robert L.; Lopez-Berestein, Gabriel; Sood, Anil K.
2011-01-01
Inherent difficulties with blocking many desirable targets using conventional approaches have prompted many to consider using RNA interference (RNAi) as a therapeutic approach. Although exploitation of RNAi has immense potential as a cancer therapeutic, many physiological obstacles stand in the way of successful and efficient delivery. This Review explores current challenges to the development of synthetic RNAi-based therapies and considers new approaches to circumvent biological barriers, to avoid intolerable side effects and to achieve controlled and sustained release. PMID:21160526
Ten million tragedies, one step at a time
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wurst, J.
Lacking the drama of nuclear weapons, ballistic missiles, or handguns, land mines have generally escaped professional and public attention. As land mines begin to be perceived as obstacles to post-war peacebuilding, some humanitarian groups and a few governments are preparing to fight the production and distribution of these weapons. Last year, a coalition of humanitarian groups including Human Rights Watch, Handicap International, Physicians for Human Rights, and the Vietman Veterans of America Foundation (VVAF) launched an international campaign to ban the production and sale of mines; the United Nations began exploring its options, and some governments called for strengthening anmore » existing convention that was designed to control mines. This article describes the types of land mines and ways in which they are used, estimates some numbers of people injured by land mines in various conflicts, and discusses the market for land mines. Measures for exposing the land mine business and for clearing existing mines are discussed.« less
[New drugs, new obstacles in the fight against HIV].
Fonseca, M S
1996-01-01
Treatment with protease inhibitors, drugs that inhibit HIV protease, an essential enzyme for the survival of the HIV virus, decreases HIV to undetectable levels and has generated great optimism. Although far from finding a cure, these findings are steps toward understanding HIV. In December 1995, the Food and Drug Administration (FDA) approved saquinavir, followed by Norvir and Crixivan, all of which are protease inhibitors. Although the availability of these drugs varies, efforts are being made to provide the drugs to everyone. President Bill Clinton has asked Congress to approve $52 million, a 50 percent increase for AIDS research, to assist people who need these drugs throughout the country. In Latin America, efforts have been made to approve these drugs. According to Miklos Salgo, director of virology at Hoffmann-La Roche, Brazil has been the first country in Central and South America to approve saquinavir. Other scientists are optimistic that these new drugs will arrive in Latin America within a year.
Targeted therapies in breast cancer: New challenges to fight against resistance
Masoud, Viviana; Pagès, Gilles
2017-01-01
Breast cancer is the most common type of cancer found in women and today represents a significant challenge to public health. With the latest breakthroughs in molecular biology and immunotherapy, very specific targeted therapies have been tailored to the specific pathophysiology of different types of breast cancers. These recent developments have contributed to a more efficient and specific treatment protocol in breast cancer patients. However, the main challenge to be further investigated still remains the emergence of therapeutic resistance mechanisms, which develop soon after the onset of therapy and need urgent attention and further elucidation. What are the recent emerging molecular resistance mechanisms in breast cancer targeted therapy and what are the best strategies to apply in order to circumvent this important obstacle? The main scope of this review is to provide a thorough update of recent developments in the field and discuss future prospects for preventing resistance mechanisms in the quest to increase overall survival of patients suffering from the disease. PMID:28439493
Serious physical fighting and gambling-related attitudes and behaviors in adolescents
Slavin, Melissa; Pilver, Corey E.; Hoff, Rani A.; Krishnan-Sarin, Suchitra; Steinberg, Marvin A.; Rugle, Loreen; Potenza, Marc N.
2013-01-01
Background and aims: Physical fighting and gambling are common risk behaviors among adolescents. Prior studies have found associations among these behaviors in adolescents but have not examined systematically the health and gambling correlates of problem-gambling severity amongst youth stratified by fight involvement. Methods: Survey data were used from 2,276 Connecticut high school adolescents regarding their physical fight involvement, gambling behaviors and perceptions, and health and functioning. Gambling perceptions and correlates of problem-gambling severity were examined in fighting and non-fighting adolescents. Results: Gambling perceptions were more permissive and at-risk/problem gambling was more frequent amongst adolescents reporting serious fights versus those denying serious fights. A stronger relationship between problem-gambling severity and regular smoking was observed for adolescents involved in fights. Discussion and conclusions: The more permissive gambling attitudes and heavier gambling associated with serious fights in high school students suggest that youth who engage in physical fights warrant enhanced prevention efforts related to gambling. The stronger relationship between tobacco smoking and problem-gambling severity amongst youth engaging in serious fights suggest that fighting youth who smoke might warrant particular screening for gambling problems and subsequent interventions. PMID:24294502
The immune strategies of mosquito Aedes aegypti against microbial infection.
Wang, Yan-Hong; Chang, Meng-Meng; Wang, Xue-Li; Zheng, Ai-Hua; Zou, Zhen
2018-06-01
Yellow fever mosquito Aedes aegypti transmits many devastating arthropod-borne viruses (arboviruses), such as dengue virus, yellow fever virus, Chikungunya virus, and Zika virus, which cause great concern to human health. Mosquito control is an effective method to block the spread of infectious diseases. Ae. aegypti uses its innate immune system to fight against arboviruses, parasites, and fungi. In this review, we briefly summarize the recent findings in the immune response of Ae. aegypti against arboviral and entomopathogenic infections. This review enriches our understanding of the mosquito immune system and provides evidence to support the development of novel mosquito control strategies. Copyright © 2017 Elsevier Ltd. All rights reserved.
Level III preventive medicine in a counterinsurgency environment.
Licina, Derek J
2008-01-01
As the Department of Defense moves forward to secure Baghdad, military forces are being strategically dispersed in very austere environments. These forces live and work side-by-side with their Iraqi counterparts in an effort to clear, hold, and reconstruct the city block by block, and further separate the insurgents from the general population. Level II preventive medicine (PM) personnel directly support these forces and keep them in the fight by reducing acute illness and disease and nonbattle injuries. Level III PM is performing the traditional PM mission of reducing both acute and chronic illness while conducting Deployment Occupational Environmental Health Surveillance and supporting Level II PM. However, the doctrinal basis of Level III allocation and priorities of core competencies have shifted. Are we meeting the need? This article attempts to answer the question based on experience as a Level III PM detachment commander in Baghdad, and provide recommendations for change across the spectrum of the Army's structure of doctrine, organizations, training, materiel, leadership, education, personnel, and facilities.
Magnesium silicide nanoparticles as a deoxygenation agent for cancer starvation therapy
NASA Astrophysics Data System (ADS)
Zhang, Chen; Ni, Dalong; Liu, Yanyan; Yao, Heliang; Bu, Wenbo; Shi, Jianlin
2017-05-01
A material that rapidly absorbs molecular oxygen (known as an oxygen scavenger or deoxygenation agent (DOA)) has various industrial applications, such as in food preservation, anticorrosion of metal and coal deoxidation. Given that oxygen is vital to cancer growth, to starve tumours through the consumption of intratumoral oxygen is a potentially useful strategy in fighting cancer. Here we show that an injectable polymer-modified magnesium silicide (Mg2Si) nanoparticle can act as a DOA by scavenging oxygen in tumours and form by-products that block tumour capillaries from being reoxygenated. The nanoparticles are prepared by a self-propagating high-temperature synthesis strategy. In the acidic tumour microenvironment, the Mg2Si releases silane, which efficiently reacts with both tissue-dissolved and haemoglobin-bound oxygen to form silicon oxide (SiO2) aggregates. This in situ formation of SiO2 blocks the tumour blood capillaries and prevents tumours from receiving new supplies of oxygen and nutrients.
Magnesium silicide nanoparticles as a deoxygenation agent for cancer starvation therapy.
Zhang, Chen; Ni, Dalong; Liu, Yanyan; Yao, Heliang; Bu, Wenbo; Shi, Jianlin
2017-05-01
A material that rapidly absorbs molecular oxygen (known as an oxygen scavenger or deoxygenation agent (DOA)) has various industrial applications, such as in food preservation, anticorrosion of metal and coal deoxidation. Given that oxygen is vital to cancer growth, to starve tumours through the consumption of intratumoral oxygen is a potentially useful strategy in fighting cancer. Here we show that an injectable polymer-modified magnesium silicide (Mg 2 Si) nanoparticle can act as a DOA by scavenging oxygen in tumours and form by-products that block tumour capillaries from being reoxygenated. The nanoparticles are prepared by a self-propagating high-temperature synthesis strategy. In the acidic tumour microenvironment, the Mg 2 Si releases silane, which efficiently reacts with both tissue-dissolved and haemoglobin-bound oxygen to form silicon oxide (SiO 2 ) aggregates. This in situ formation of SiO 2 blocks the tumour blood capillaries and prevents tumours from receiving new supplies of oxygen and nutrients.
NASA Technical Reports Server (NTRS)
Tenney, Darrel R.; Davis, John G., Jr.; Johnston, Norman J.; Pipes, R. Byron; McGuire, Jack F.
2011-01-01
This serves as a source of collated information on Composite Research over the past four decades at NASA Langley Research Center, and is a key reference for readers wishing to grasp the underlying principles and challenges associated with developing and applying advanced composite materials to new aerospace vehicle concepts. Second, it identifies the major obstacles encountered in developing and applying composites on advanced flight vehicles, as well as lessons learned in overcoming these obstacles. Third, it points out current barriers and challenges to further application of composites on future vehicles. This is extremely valuable for steering research in the future, when new breakthroughs in materials or processing science may eliminate/minimize some of the barriers that have traditionally blocked the expanded application of composite to new structural or revolutionary vehicle concepts. Finally, a review of past work and identification of future challenges will hopefully inspire new research opportunities and development of revolutionary materials and structural concepts to revolutionize future flight vehicles.
Fighting with Siblings and with Peers among Urban High School Students
Johnson, Renee M.; Duncan, Dustin T.; Rothman, Emily F.; Gilreath, Tamika D.; Hemenway, David; Molnar, Beth E.; Azrael, Deborah
2014-01-01
Understanding the determinants of fighting is important for prevention efforts. Unfortunately, there is little research on how sibling fighting is related to peer fighting. Therefore, the aim of this study was to evaluate the association between sibling fighting and peer fighting. Data are from the Boston Youth Survey 2008, a school-based sample of youth in Boston, MA. To estimate the association between sibling fighting and peer fighting we ran four multivariate regression models and estimated adjusted prevalence ratios and 95% confidence intervals. We fit generalized estimating equation models to account for the fact that students were clustered within schools. Controlling for school clustering, race/ethnicity, sex, school failure, substance use, and caregiver aggression, youth who fought with siblings were 2.49 times more likely to have reported fighting with peers. To the extent that we can confirm that sibling violence is associated with aggressive behavior, we should incorporate it into violence prevention programming. PMID:25287411
A Multi-Beam Interferometer and Its Use as a Screening System in Gynecologic Cytology
NASA Astrophysics Data System (ADS)
Fujii, Ken-ichi; Suzuki, Norihito
1982-11-01
Clumps of cells remaining after the cell separation process present the greatest obstacle to the development of an automated screening system using flow cytofluorometry. There are two main problems caused by such clumps of cells. One occurs in the flow system, when the clumps block the nozzles, while the other occurs in the measuring system, when the clumps give a false fluorescence intensity. The former problem can be solved by designing the flow system appropriately, and the latter can be obviated by using a multi-beam interferometer.
Plane Smoothers for Multiblock Grids: Computational Aspects
NASA Technical Reports Server (NTRS)
Llorente, Ignacio M.; Diskin, Boris; Melson, N. Duane
1999-01-01
Standard multigrid methods are not well suited for problems with anisotropic discrete operators, which can occur, for example, on grids that are stretched in order to resolve a boundary layer. One of the most efficient approaches to yield robust methods is the combination of standard coarsening with alternating-direction plane relaxation in the three dimensions. However, this approach may be difficult to implement in codes with multiblock structured grids because there may be no natural definition of global lines or planes. This inherent obstacle limits the range of an implicit smoother to only the portion of the computational domain in the current block. This report studies in detail, both numerically and analytically, the behavior of blockwise plane smoothers in order to provide guidance to engineers who use block-structured grids. The results obtained so far show alternating-direction plane smoothers to be very robust, even on multiblock grids. In common computational fluid dynamics multiblock simulations, where the number of subdomains crossed by the line of a strong anisotropy is low (up to four), textbook multigrid convergence rates can be obtained with a small overlap of cells between neighboring blocks.
McMullen, Katherine Y.; Poppe, Lawrence J.; Danforth, William W.; Blackwood, Dann S.; Winner, William G.; Parker, Castle E.
2015-01-01
Multibeam-bathymetric and sidescan-sonar data, collected by the National Oceanic and Atmospheric Administration in a 114-square-kilometer area of Block Island Sound, southeast of Fishers Island, New York, are combined with sediment samples and bottom photography collected by the U.S. Geological Survey from 36 stations in this area in order to interpret sea-floor features and sedimentary environments. These interpretations and datasets provide base maps for studies on benthic ecology and resource management. The geologic features and sedimentary environments on the sea floor are products of the area’s glacial history and modern processes. These features include bedrock, drumlins, boulders, cobbles, large current-scoured bathymetric depressions, obstacle marks, and glaciolacustrine sediments found in high-energy sedimentary environments of erosion or nondeposition; and sand waves and megaripples in sedimentary environments characterized by coarse-grained bedload transport. Trawl marks are preserved in lower energy environments of sorting and reworking. This report releases the multibeam-bathymetric, sidescan-sonar, sediment, and photographic data and interpretations of the features and sedimentary environments in Block Island Sound, offshore Fishers Island.
Fighting With Siblings and With Peers Among Urban High School Students.
Johnson, Renee M; Duncan, Dustin T; Rothman, Emily F; Gilreath, Tamika D; Hemenway, David; Molnar, Beth E; Azrael, Deborah
2015-08-01
Understanding the determinants of fighting is important for prevention efforts. Unfortunately, there is little research on how sibling fighting is related to peer fighting. Therefore, the aim of this study was to evaluate the association between sibling fighting and peer fighting. Data are from the Boston Youth Survey 2008, a school-based sample of youth in Boston, MA. To estimate the association between sibling fighting and peer fighting, we ran four multivariate regression models and estimated adjusted prevalence ratios and 95% confidence intervals. We fit generalized estimating equation models to account for the fact that students were clustered within schools. Controlling for school clustering, race/ethnicity, sex, school failure, substance use, and caregiver aggression, youth who fought with siblings were 2.49 times more likely to have reported fighting with peers. To the extent that we can confirm that sibling violence is associated with aggressive behavior, we should incorporate it into violence prevention programming. © The Author(s) 2014.
Gettel, Douglas L; Sanborn, Jeremy; Patel, Mira A; de Hoog, Hans-Peter; Liedberg, Bo; Nallani, Madhavan; Parikh, Atul N
2014-07-23
Substrate-mediated fusion of small polymersomes, derived from mixtures of lipids and amphiphilic block copolymers, produces hybrid, supported planar bilayers at hydrophilic surfaces, monolayers at hydrophobic surfaces, and binary monolayer/bilayer patterns at amphiphilic surfaces, directly responding to local measures of (and variations in) surface free energy. Despite the large thickness mismatch in their hydrophobic cores, the hybrid membranes do not exhibit microscopic phase separation, reflecting irreversible adsorption and limited lateral reorganization of the polymer component. With increasing fluid-phase lipid fraction, these hybrid, supported membranes undergo a fluidity transition, producing a fully percolating fluid lipid phase beyond a critical area fraction, which matches the percolation threshold for the immobile point obstacles. This then suggests that polymer-lipid hybrid membranes might be useful models for studying obstructed diffusion, such as occurs in lipid membranes containing proteins.
NASA Astrophysics Data System (ADS)
Moriwaki, Katsumi; Koike, Issei; Sano, Tsuyoshi; Fukunaga, Tetsuya; Tanaka, Katsuyuki
We propose a new method of environmental recognition around an autonomous vehicle using dual vision sensor and navigation control based on binocular images. We consider to develop a guide robot that can play the role of a guide dog as the aid to people such as the visually impaired or the aged, as an application of above-mentioned techniques. This paper presents a recognition algorithm, which finds out the line of a series of Braille blocks and the boundary line between a sidewalk and a roadway where a difference in level exists by binocular images obtained from a pair of parallelarrayed CCD cameras. This paper also presents a tracking algorithm, with which the guide robot traces along a series of Braille blocks and avoids obstacles and unsafe areas which exist in the way of a person with the guide robot.
Pellis, Sergio M; Pellis, Vivien C
2018-02-01
Play fighting is a commonly reported form of play that involves competitive interactions that generally do not escalate to serious fighting. Although in many species what are competed over are the body targets that are bitten or struck in serious fighting, for many others, the competition can be over other forms of contact, such as sex, social grooming, and predation. In primates, the most detailed studies have been of species such as Old World monkeys, that engage in play fighting that simulates serious fighting, but reports of a number of others, especially among nocturnal prosimians, have noted that play fighting can also involve simulation of sex and grooming. The present study on captive born gray mouse lemurs ( Microcebus murinus ) provides a quantitative assessment of the relative engagement by juveniles in play fighting involving agonistic and amicable targets. About 80% of play fighting involves competing to groom or mount one another, with a minority involving competing to bite. That these forms of play fighting may be distinct from one another is suggested by the finding that attack on one target does not lead to counterattack on another. The findings are discussed in terms of the evolution and mechanisms underlying play fighting in primates and more widely among animals. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Fighting experience affects fruit fly behavior in a mating context
NASA Astrophysics Data System (ADS)
Teseo, Serafino; Veerus, Liisa; Mery, Frédéric
2016-06-01
In animals, correlations exist among behaviors within individuals, but it is unclear whether experience in a specific functional context can affect behavior across different contexts. Here, we use Drosophila melanogaster to investigate the effects of conflict-induced behavioral modifications on male mating behavior. In D. melanogaster, males fight for territories and experience a strong winner-loser effect, meaning that winners become more likely to win subsequent fights compared to losers, who continue to lose. In our protocol, males were tested for courtship intensity before and after fighting against other males. We show that male motivation to copulate before fights cannot predict the fight outcomes, but that, afterwards, losers mate less than before and less than winner and control males. Contrarily, winners show no differences between pre- and post-fight courtship intensity, and do not differ from control males. This suggests that the physiological modifications resulting from fight outcomes indirectly affect male reproductive behavior.
Chen, RuiJun; Flores, Glenn; Shetgiri, Rashmi
2015-01-01
Adolescent fighting affects 25% of youth, with the highest rates among African-Americans and Latinos but little is known about parental views on youth fighting. The purpose of this study was to examine African-American and Latino parents’ perspectives on adolescent fighting and methods to prevent fighting. We conducted four focus groups with parents of African-American and Latino urban adolescents. Focus groups were stratified by race/ethnicity and fighting status. Groups were audiotaped, transcribed, and analyzed by three independent coders using thematic content analysis. Seventy-six percent of the 17 participants were female. Latino parents condoned fighting only as a last resort, and taught children about consequences of fighting, emotional regulation, and non-violent conflict-resolution strategies. African-American parents endorsed teaching non-violent strategies, but expressed some doubts about their effectiveness. African-American parents also suggested corporal punishment, but acknowledged that this may not be an optimal long-term strategy. Positive role modeling and involvement by teachers and other adults were cited as having important roles in fighting prevention. Suggested interventions included teaching adolescents non-violent conflict-resolution skills, anger management, and alternatives to fighting. Parents recommended that violence prevention programs incorporate the experiences of former fighters and be tailored to community needs. Study findings suggest that youth violence-prevention programs may benefit from addressing parental attitudes towards fighting and parent-child communication about fighting, teaching adolescents non-violent conflict-resolution skills, and tailoring programs by race/ethnicity. Promoting positive modeling and involvement by teachers and other adults also may be beneficial. PMID:27186064
Chen, RuiJun; Flores, Glenn; Shetgiri, Rashmi
2016-06-01
Adolescent fighting affects 25% of youth, with the highest rates among African-Americans and Latinos but little is known about parental views on youth fighting. The purpose of this study was to examine African-American and Latino parents' perspectives on adolescent fighting and methods to prevent fighting. We conducted four focus groups with parents of African-American and Latino urban adolescents. Focus groups were stratified by race/ethnicity and fighting status. Groups were audiotaped, transcribed, and analyzed by three independent coders using thematic content analysis. Seventy-six percent of the 17 participants were female. Latino parents condoned fighting only as a last resort, and taught children about consequences of fighting, emotional regulation, and non-violent conflict-resolution strategies. African-American parents endorsed teaching non-violent strategies, but expressed some doubts about their effectiveness. African-American parents also suggested corporal punishment, but acknowledged that this may not be an optimal long-term strategy. Positive role modeling and involvement by teachers and other adults were cited as having important roles in fighting prevention. Suggested interventions included teaching adolescents non-violent conflict-resolution skills, anger management, and alternatives to fighting. Parents recommended that violence prevention programs incorporate the experiences of former fighters and be tailored to community needs. Study findings suggest that youth violence-prevention programs may benefit from addressing parental attitudes towards fighting and parent-child communication about fighting, teaching adolescents non-violent conflict-resolution skills, and tailoring programs by race/ethnicity. Promoting positive modeling and involvement by teachers and other adults also may be beneficial.
Rumble: Prevalence and Correlates of Group Fighting among Adolescents in the United States
DeLisi, Matt; Vaughn, Michael G.; Salas-Wright, Christopher P.
2015-01-01
Objective. Group fighting is portrayed as a piece of Americana among delinquent youth, but the behavior produces significant multifaceted negative consequences. The current study examines the heterogeneity and correlates of group fighting using national-level data. Method. Employing data from the National Survey on Drug Use and Health between 2002 and 2013 (n = 216,852), we examine links between group fighting and temperamental, parental, and academic factors as well as other externalizing behaviors (i.e., violence, crime, substance use). Results. The prevalence of group fighting in the United States is 14.8% with 11.33% reporting 1–2 group fights and 3.46% reporting 3+ group fights. A clear severity gradient in school functioning and academic performance, sensation seeking, parental disengagement, violence and delinquency, and substance use disorders is seen in the normative, episodic, and repeat offender groups. Conclusions. Youths who participate in 3+ group fights display the exceptionality and severity of other serious/chronic/habitual antisocial youth which suggests that group fighting should be considered a significant indicator of developing criminality. PMID:25945950
The Global Fund: managing great expectations.
Brugha, Ruairí; Donoghue, Martine; Starling, Mary; Ndubani, Phillimon; Ssengooba, Freddie; Fernandes, Benedita; Walt, Gill
The Global Fund to fight AIDS, Tuberculosis, and Malaria was created to increase funds to combat these three devastating diseases. We report interim findings, based on interviews with 137 national-level respondents that track early implementation processes in four African countries. Country coordinating mechanisms (CCMs) are country-level partnerships, which were formed quickly to develop and submit grant proposals to the Global Fund. CCM members were often ineffective at representing their constituencies and encountered obstacles in participating in CCM processes. Delay in dissemination of guidelines from the Global Fund led to uncertainty among members about the function of these new partnerships. Respondents expressed most concern about the limited capacity of fund recipients--government and non-government--to meet Global Fund conditions for performance-based disbursement. Delays in payment of funds to implementing agencies have frustrated rapid financing of disease control interventions. The Global Fund is one of several new global initiatives superimposed on existing country systems to finance the control of HIV/AIDS. New and existing donors need to coordinate assistance to developing countries by bringing together funding, planning, management, and reporting systems if global goals for disease control are to be achieved.
Perceived aggressiveness predicts fighting performance in mixed-martial-arts fighters.
Trebicky, Vít; Havlícek, Jan; Roberts, S Craig; Little, Anthony C; Kleisner, Karel
2013-09-01
Accurate assessment of competitive ability is a critical component of contest behavior in animals, and it could be just as important in human competition, particularly in human ancestral populations. Here, we tested the role that facial perception plays in this assessment by investigating the association between both perceived aggressiveness and perceived fighting ability in fighters' faces and their actual fighting success. Perceived aggressiveness was positively associated with the proportion of fights won, after we controlled for the effect of weight, which also independently predicted perceived aggression. In contrast, perception of fighting ability was confounded by weight, and an association between perceived fighting ability and actual fighting success was restricted to heavyweight fighters. Shape regressions revealed that aggressive-looking faces are generally wider and have a broader chin, more prominent eyebrows, and a larger nose than less aggressive-looking faces. Our results indicate that perception of aggressiveness and fighting ability might cue different aspects of success in male-male physical confrontation.
NASA Astrophysics Data System (ADS)
Sripramai, Keerati; Oikawa, Yasushi; Watanabe, Hiroshi; Katada, Toshitaka
Generally, in order to improve some regional fire fighting validity, indispensable strategies are not only a reinforcement of the governmental fire fighting ability, but also a strengthening of the cooperative relationship between governmental and non-governmental fire fighting ability. However, for practical purposes, the effective strategy should be different depending on the actual situationin the subject area. So, in this study, we grasp the actual state and background of the problems that need to be solved for the improvement of the regional fire fighting validity in Bangkok as a case study, and examine the appropriate solution focusing on the relationship between official and voluntary fire fighting. Through some practicable activities such as interviews, investigati ons, and making the regional fire fighting validity map, it became clear that the problems of uncooperative relationship and the lack of trust between stakeholders should be solved first and foremost.
14 CFR 121.106 - ETOPS Alternate Airport: Rescue and fire fighting service.
Code of Federal Regulations, 2011 CFR
2011-01-01
... augmented to meet paragraph (a) of this section from local fire fighting assets. A 30-minute response time... fighting service. 121.106 Section 121.106 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... and Flag Operations § 121.106 ETOPS Alternate Airport: Rescue and fire fighting service. (a) Except as...
14 CFR 121.106 - ETOPS Alternate Airport: Rescue and fire fighting service.
Code of Federal Regulations, 2010 CFR
2010-01-01
... augmented to meet paragraph (a) of this section from local fire fighting assets. A 30-minute response time... fighting service. 121.106 Section 121.106 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... and Flag Operations § 121.106 ETOPS Alternate Airport: Rescue and fire fighting service. (a) Except as...
The Fighting Phenomenon: What It Means to Be a Girl Who Fights
ERIC Educational Resources Information Center
Seibert, Maureen Louise
2010-01-01
The purpose of this study is to investigate why girls in an urban high school setting engage in physical fights in order to better understand the female student's mindset about fighting. A search of ERIC, Sociological Abstracts, Psychological Abstracts, Dissertation Abstracts and dissertations was conducted to review research in the following…
Rudin, Fabian S; Briffa, Mark
2012-05-22
Contest theory predicts the evolution of a stable mixture of different strategies for fighting. Here, we investigate the possibility that stable between-individual differences in startle-response durations influence fighting ability or 'resource-holding potential' (RHP) in the beadlet sea anemone, Actinia equina. Both winners and losers showed significant repeatability of pre-fight startle-response durations but mean pre-fight startle-response durations were greater for eventual losers than for eventual winners, indicating that RHP varies with boldness. In particular, individuals with short startle responses inflicted more attacks on their opponent. Both repeatability and mean-level responses were changed by the experience of fighting, and these changes varied with outcome. In losers, repeatability was disrupted to a greater extent and the mean startle-response durations were subject to a greater increase than in winners. Thus, following a fight, this behavioural correlate of RHP behaves in a way similar to post-fight changes in physiological status, which can also vary between winners and losers. Understanding the links between aggression and boldness therefore has the potential to enhance our understanding of both the evolution of animal personality and the 'winner and loser effects' of post-fight changes in RHP.
Learning and memory associated with aggression in Drosophila melanogaster
Yurkovic, Alexandra; Wang, Oulu; Basu, Alo C.; Kravitz, Edward A.
2006-01-01
Male Drosophila melanogaster (Canton-S strain) exhibit aggression in competition for resources, to defend territory, and for access to mates. In the study reported here, we asked: (i) how long flies fight; (ii) whether flies adopt distinct winning and losing strategies as hierarchical relationships are established; (iii) whether flies exhibit experience-dependent changes in fighting strategies in later fights; and (iv) whether flies fight differently in second fights against familiar or unfamiliar opponents. The results showed that flies fought for up to 5 h. As hierarchical relationships were established, behavioral strategies changed: winners progressively lunged more and retreated less, whereas losers progressively lunged less and retreated more. Encounters between flies were frequent during the first 10 min of pairing and then dropped significantly. To ask whether flies remembered previous fights, they were re-paired with familiar or unfamiliar opponents after 30 min of separation. In familiar pairings, there were fewer encounters during the first 10 min of fighting than in unfamiliar pairings, and former losers fought differently against familiar winners than unfamiliar winners. Former losers lost or no decision was reached in all second fights in pairings with familiar or unfamiliar winners or with naive flies. Winner/winner, loser/loser, and naive/naive pairings revealed that losers used low-intensity strategies in later fights and were unlikely to form new hierarchical relationships, compared with winners or socially naive flies. These results strongly support the idea that learning and memory accompany the changes in social status that result from fruit fly fights. PMID:17088536
NASA Technical Reports Server (NTRS)
Miller, C. G.; Stephens, J. B. (Inventor)
1978-01-01
Shallow pools of liquid to collect low-temperature solar generated thermal energy are described. Narrow elongated trenches, grouped together over a wide area, are lined with a heat-absorbing black liner. The heat-absorbing liquid is kept separate from the thermal energy removing fluid by means such as clear polyethylene material. The covering for the pond may be a fluid or solid. If the covering is a fluid, fire fighting foam, continuously generated, or siloons are used to keep the surface covering clean and insulated. If the thermal energy removing fluid is a gas, a fluid insulation layer contained in a flat polyethlene tubing is used to cover the pond. The side of the tube directed towards the sun is treated to block out ultraviolet radiation and trap in infrared radiation.
Peptides and peptidomimetics as immunomodulators
Gokhale, Ameya S; Satyanarayanajois, Seetharama
2014-01-01
Peptides and peptidomimetics can function as immunomodulating agents by either blocking the immune response or stimulating the immune response to generate tolerance. Knowledge of B- or T-cell epitopes along with conformational constraints is important in the design of peptide-based immunomodulating agents. Work on the conformational aspects of peptides, synthesis and modified amino acid side chains have contributed to the development of a new generation of therapeutic agents for autoimmune diseases and cancer. The design of peptides/peptidomimetics for immunomodulation in autoimmune diseases such as multiple sclerosis, rheumatoid arthritis, systemic lupus and HIV infection is reviewed. In cancer therapy, peptide epitopes are used in such a way that the body is trained to recognize and fight the cancer cells locally as well as systemically. PMID:25186605
Methodological Encounters with the Phenomenal Kind.
Shea, Nicholas
2012-03-01
Block's well-known distinction between phenomenal consciousness and access consciousness has generated a large philosophical literature about putative conceptual connections between the two. The scientific literature about whether they come apart in any actual cases is rather smaller. Empirical evidence gathered to date has not settled the issue. Some put this down to a fundamental methodological obstacle to the empirical study of the relation between phenomenal consciousness and access consciousness. Block (2007) has drawn attention to the methodological puzzle and attempted to answer it. While the evidence Block points to is relevant and important, this paper puts forward a more systematic framework for addressing the puzzle. To give it a label, the approach is to study phenomenal consciousness as a natural kind. The approach allows consciousness studies to move beyond initial means of identifying instances of the kind like verbal report, and to find its underlying nature. It is well-recognised that facts about an underlying kind may allow identification of instances of the kind that do not match the initial means of identification (cp. non-liquid samples of water). This paper shows that the same method can be deployed to investigate phenomenal consciousness independently of access consciousness.
The Schoolyard as a Stage: Missing Cultural Clues in Symbolic Fighting.
ERIC Educational Resources Information Center
Arriaza, Gilberto
2003-01-01
Investigates how social conflict was enacted at one racially diverse, urban middle school. Discusses symbolic fighting, the use of body language, the location of symbolic fighting, and symbolic fighting as a source of transformation, proposing to redefine the socializing role of social conflict in the lives of students and adults in schools.…
[Development of child mental health services in Lithuania: achievements and obstacles].
Pūras, Dainius
2002-01-01
In 1990, political, economic and social changes in Lithuania introduced the possibility to develop for the first time in nations's history an effective and modern system of child mental health services. During the period between 1990 and 1995 a new model of services was developed in the Department of Social pediatrics and child psychiatry of Vilnius University. The model included development of child and adolescent psychiatric services, as well as early intervention services for infants and preschool children with developmental disabilities. The emphasis, following recommendations of WHO and existing international standards, was made on deinstitutionalization and development of family-oriented and community-based services, which have been ignored by previous system. In the first half of 90's of 20th century, new training programs for professionals were introduced, more than 50 methods of assessment, treatment and rehabilitation, new for Lithuanian clinical practice, were implemented, and a new model of services, including primary, secondary and tertiary level of prevention, was introduced in demonstration sites. However, during next phase of development, in 1997-2001, serious obstacles for replicating new approaches across the country, have been identified, which threatened successful implementation of the new model of services into everyday clinical practice. Analysis of obstacles, which are blocking development of new approaches in the field of child mental health, is presented in the article. The main obstacles, identified during analysis of socioeconomic context, planning and utilization of resources, running of the system of services and evaluation of outcomes, are as follows: lack of intersectorial cooperation between health, education and social welfare systems; strong tradition of discrimination of psychosocial interventions in funding schemes of health services; societal attitudes, which tend to discriminate and stigmatize marginal groups, including disabled children and dysfunctional families; lack of evidence-based decision making in the process of health care reform and reform of social infrastructure.
Proteins mediating DNA loops effectively block transcription.
Vörös, Zsuzsanna; Yan, Yan; Kovari, Daniel T; Finzi, Laura; Dunlap, David
2017-07-01
Loops are ubiquitous topological elements formed when proteins simultaneously bind to two noncontiguous DNA sites. While a loop-mediating protein may regulate initiation at a promoter, the presence of the protein at the other site may be an obstacle for RNA polymerases (RNAP) transcribing a different gene. To test whether a DNA loop alters the extent to which a protein blocks transcription, the lac repressor (LacI) was used. The outcome of in vitro transcription along templates containing two LacI operators separated by 400 bp in the presence of LacI concentrations that produced both looped and unlooped molecules was visualized with scanning force microscopy (SFM). An analysis of transcription elongation complexes, moving for 60 s at an average of 10 nt/s on unlooped DNA templates, revealed that they more often surpassed LacI bound to the lower affinity O2 operator than to the highest affinity Os operator. However, this difference was abrogated in looped DNA molecules where LacI became a strong roadblock independently of the affinity of the operator. Recordings of transcription elongation complexes, using magnetic tweezers, confirmed that they halted for several minutes upon encountering a LacI bound to a single operator. The average pause lifetime is compatible with RNAP waiting for LacI dissociation, however, the LacI open conformation visualized in the SFM images also suggests that LacI could straddle RNAP to let it pass. Independently of the mechanism by which RNAP bypasses the LacI roadblock, the data indicate that an obstacle with looped topology more effectively interferes with transcription. © 2017 The Authors Protein Science published by Wiley Periodicals, Inc. on behalf of The Protein Society.
Kodjo, Cheryl M; Auinger, Peggy; Ryan, Sheryl A
2004-10-01
To determine: (a) the prevalence of physical fighting while under the influence of alcohol or drugs, and (b) the associations among demographic factors, other risk behaviors, and physical fighting while under the influence of substances. Cross-sectional analysis of The National Longitudinal Study of Adolescent Health (Add Health) 1994-1995, a school-based, nationally representative survey of 6504 7th to 12th graders. The dependent outcome variables of interest were: "The most recent time you got into a fight, had you been drinking?" and "Have you ever gotten into a fight when you had been using drugs?" Independent variables included: demographics, adolescent characteristics and risk behaviors, home environment, and peer substance use. Univariate and bivariate analyses, and logistic regressions, using SUDAAN, were performed for the two outcome behaviors for the overall sample (p = .05). Eleven percent of both drinkers (n = 1110) and drug users (n = 1869) reported being under the influence while fighting. These adolescents were significantly more likely to injure or sustain injury than their counterparts. Selling drugs, gang fighting, and peer substance use were significantly associated with both outcomes. A significant proportion of adolescents who use substances also engage in physical fighting while under the influence. Health providers should counsel their patients about the potential for injury and be mindful that concurrent fighting and substance use may be markers for other more high-risk delinquent behaviors.
... he or she is hitting others. This teaches the child to use aggressive behavior. Parents should not ignore or downplay aggressive fighting between siblings. When hitting or fighting is frequent, it may ...
Saxon, Emma
2016-01-19
Male crickets (Gryllus bimaculatus) establish dominance hierarchies within a population by fighting with one another. Larger males win fights more frequently than their smaller counterparts, and a previous study found that males recognise one another primarily through sensory input from the antennae. This study therefore investigated whether the success of larger crickets is influenced by sensory input from the antennae, in part by assessing the number of fights that large 'antennectomized' crickets won against small crickets, compared with the number that large, intact crickets won. The success rate was significantly lower in antennectomized males, though they still won the majority of fights (73/100 versus 58/100, Fisher's exact test P < 0.05); the authors thus conclude that sensory input from the antennae affects the fighting success of large males, but that other size-related factors also play a part.
Fight Bite Injuries: Aggressive Tendencies Associated with Smaller Second to Fourth Digit Ratio.
Joyce, Cormac W; O' Regan, Andrew; Kelly, Jack L; O' Shaughnessy, Michael
2017-12-01
Fight bite injuries are typically sustained by young, combative males and are the direct consequence of an aggressive act. Second to fourth digit ratios (2D:4D) are dependent on prenatal androgen exposure and lower ratios have been shown to be linked to various psychological and physical traits, including aggression. The aim of this study was to examine the 2D:4D ratios in a cohort of patients with fight bite injuries and compare these to an age and gender-matched control group. The 2D:4D ratios were calculated using plain films of the hand from 133 patients (122 males, 11 females) with fight bite injuries. A further 133 radiographs were obtained from patients that did not have fight bite injuries and digit ratios were calculated in the same fashion. Statistical analysis was then carried out to compare the 2D:4D ratios between the different groups. The 2D:4D ratios for male fight bite patients was significantly smaller than the male control group (p < 0.05). No significant difference was observed between the female fight bite patients and the female control group (p > 0.05). Fight bite injuries are usually sustained as a result of aggression. 2D:4D ratios are reflect intrauterine androgen exposure and low ratios have been linked to aggressive tendencies. We have demonstrated that male patients who sustained fight bite injuries have a lower 2D:4D ratio then the general population, thereby suggesting that exposure to prenatal androgens can lead to aggressive tendencies in adulthood. This suggests that lower ratios may predict a predisposition to acts of aggression, and as such result in an increased likelihood of sustaining an injury such as a fight bite.
Obstacles to reduction in infantile developmental dysplasia of the hip.
Studer, K; Williams, N; Studer, P; Baker, M; Glynn, A; Foster, B K; Cundy, P J
2017-10-01
Identification of anatomical structures that block -reduction in developmental dysplasia of the hip (DDH) is -important for the management of this challenging condition. Obstacles to reduction seen on arthrogram are well-known. However, despite the increasing use of MRI in the assessment of adequacy of reduction in DDH, the interpretation of MRI patho-anatomy is ill-defined with a lack of relevant literature to guide clinicians. This is a retrospective analysis of the MRI of patients with DDH treated by closed reduction over a five-year period (between 2009 and 2014). Neuromuscular and genetic disorders were excluded. Each MRI was analysed by two orthopaedic surgeons and a paediatric musculoskeletal radiologist to identify the ligamentum teres, pulvinar, transverse acetabular ligament (TAL), capsule, labrum and acetabular roof cartilage hypertrophy. Inter- and intraobserver reliability was calculated. The minimum follow-up was 12 months. A total of 29 patients (38 hips) underwent closed reduction for treatment of DDH. Eight hips showed persistent subluxation on post-operative MRI. Only three of these eight hips showed an abnormality on arthrogram. The pulvinar was frequently interpreted as 'abnormal' on MRI. The main obstacles identified on MRI were the ligamentum teres (15.8%), labrum (13.1%) and acetabular roof cartilage hypertrophy (13.2%). The inter-rater reliability was good for TAL, capsule and pulvinar; moderate for ligamentum teres and labrum; and poor for hypertrophied cartilage. The labrum, ligamentum teres and acetabular roof cartilage hypertrophy are the most important structures seen on MRI preventing complete reduction of DDH. Focused interpretation of these structures may assist in the management of DDH.
Gupta, Rahul
2018-02-01
AMPA receptors (AMPARs) and their associations with auxiliary transmembrane proteins are bulky structures with large steric-exclusion volumes. Hence, self-crowding of AMPARs, depending on the local density, may affect their lateral diffusion in the postsynaptic membrane as well as in the highly crowded postsynaptic density (PSD) at excitatory synapses. Earlier theoretical studies considered only the roles of transmembrane obstacles and the AMPAR-binding submembranous scaffold proteins in shaping receptor diffusion within PSD. Using lattice model of diffusion, the present study investigates the additional impacts of self-crowding on the anomalousity and effective diffusion coefficient (Deff) of AMPAR diffusion. A recursive algorithm for avoiding false self-blocking during diffusion simulation is also proposed. The findings suggest that high density of AMPARs in the obstacle-free membrane itself engenders strongly anomalous diffusion and severe decline in Deff. Adding transmembrane obstacles to the membrane accentuates the anomalousity arising from self-crowding due to the reduced free diffusion space. Contrarily, enhanced AMPAR-scaffold binding, either through increase in binding strength or scaffold density or both, ameliorates the anomalousity resulting from self-crowding. However, binding has differential impacts on Deff depending on the receptor density. Increase in binding causes consistent decrease in Deff for low and moderate receptor density. For high density, binding increases Deff as long as it reduces anomalousity associated with intense self-crowding. Given a sufficiently strong binding condition when diffusion acquires normal behavior, further increase in binding causes decrease in Deff. Supporting earlier experimental observations are mentioned and implications of present findings to the experimental observations on AMPAR diffusion are also drawn.
Structural adaptations to diverse fighting styles in sexually selected weapons
McCullough, Erin L.; Tobalske, Bret W.; Emlen, Douglas J.
2014-01-01
The shapes of sexually selected weapons differ widely among species, but the drivers of this diversity remain poorly understood. Existing explanations suggest weapon shapes reflect structural adaptations to different fighting styles, yet explicit tests of this hypothesis are lacking. We constructed finite element models of the horns of different rhinoceros beetle species to test whether functional specializations for increased performance under species-specific fighting styles could have contributed to the diversification of weapon form. We find that horns are both stronger and stiffer in response to species-typical fighting loads and that they perform more poorly under atypical fighting loads, which suggests weapons are structurally adapted to meet the functional demands of fighting. Our research establishes a critical link between weapon form and function, revealing one way male–male competition can drive the diversification of animal weapons. PMID:25201949
Structural adaptations to diverse fighting styles in sexually selected weapons.
McCullough, Erin L; Tobalske, Bret W; Emlen, Douglas J
2014-10-07
The shapes of sexually selected weapons differ widely among species, but the drivers of this diversity remain poorly understood. Existing explanations suggest weapon shapes reflect structural adaptations to different fighting styles, yet explicit tests of this hypothesis are lacking. We constructed finite element models of the horns of different rhinoceros beetle species to test whether functional specializations for increased performance under species-specific fighting styles could have contributed to the diversification of weapon form. We find that horns are both stronger and stiffer in response to species-typical fighting loads and that they perform more poorly under atypical fighting loads, which suggests weapons are structurally adapted to meet the functional demands of fighting. Our research establishes a critical link between weapon form and function, revealing one way male-male competition can drive the diversification of animal weapons.
FiGHTS: a preliminary screening tool for adolescent firearms-carrying.
Hayes, D Neil; Sege, Robert
2003-12-01
Adolescent firearms-carrying is a risk factor for serious injury and death. Clinical screening tools for firearms-carrying have not yet been developed. We present the development of a preliminary screening test for adolescent firearms-carrying based on the growing body of knowledge of firearms-related risk factors. A convenience sample of 15,000 high school students from the 1999 National Youth Risk Behavior Survey was analyzed for the purpose of model building. Known risk factors for firearms-carrying were candidates for 2 models predicting recent firearms-carrying. The "brief FiGHTS score" screening tool excluded terms related to sexual behavior, significant substance abuse, or criminal behavior (Fi=fighting, G=gender, H=hurt while fighting, T=threatened, S=smoker). An "extended FiGHTS score," which included 13 items, was developed for more precise estimates. The brief FiGHTS score had a sensitivity of 82%, a specificity of 71%, and an area under the receiver operating characteristic (ROC) curve of 0.84. The extended FiGHTS score had an area under the ROC curve of 0.90. Both models performed well in a validation data set of 55,000 students. The brief and extended FiGHTS scores have high sensitivity and specificity for predicting firearms-carrying and may be appropriate for clinical testing.
Knocking down disease: a progress report on siRNA therapeutics
Wittrup, Anders; Lieberman, Judy
2016-01-01
Small interfering RNAs (siRNAs), which downregulate gene expression guided by sequence complementarity, can be used therapeutically to block the synthesis of disease-causing proteins. The main obstacle to siRNA drugs — their delivery into the target cell cytosol — has been overcome to allow suppression of liver gene expression. Here, we review the results of recent clinical trials of siRNA therapeutics, which show efficient and durable gene knockdown in the liver, with signs of promising clinical outcomes and little toxicity. We also discuss the barriers to more widespread applications that target tissues besides the liver and the most promising avenues to overcome them. PMID:26281785
C/STOL flight in wind disturbed by the presence of buildings
NASA Technical Reports Server (NTRS)
Frost, W.; Reddy, R.; Crosby, B.; Camp, D. W.
1978-01-01
This paper investigates the behavior of winds about block geometries characteristic of building shapes and of the flight performance of aircraft with characteristics of a DC-8 and a DHC-6 as they fly through the wind fields. The two-dimensional equations of motion for the aircraft are written to include variable winds and wind shear components. The paper also presents a discussion of the influence of those terms in the equations of motion which explicitly contain effects due to wind shear. Also included is a study of the aircrafts' flight paths over the obstacles with both a fixed stick and an automatic landing system.
Nieuwveld, D; Mojica, V; Herrera, A E; Pomés, J; Prats, A; Sala-Blanch, X
2017-04-01
Ultrasound-guided infraclavicular block in the costoclavicular space located between the clavicle and the first rib, reaches the secondary trunks when they are clustered together and lateral to the axillary artery. This block is most often performed through a lateral approach, the difficulty being finding the coracoid process an obstacle and guiding the needle towards the vessels and pleura. A medial approach, meaning from inside to outside, will avoid these structures. Traditionally the assessment of a successful block is through motor or sensitive responses but a sympathetic fibre block can also be evaluated measuring the changes in humeral artery blood flow, skin temperature and/or perfusion index. To describe the medial approach of the ultrasound-guided costoclavicular block evaluating its development by motor and sensitive response and measurement of sympathetic changes. Description of the technique and administration of 20ml of contrast in a fresh cadaver model, evaluating the distribution with CT-scan and sagittal sections of the anatomic piece. Subsequently in a clinical phase, including 11 patients, we evaluated the establishment of motor, sensitive and sympathetic blocks. We evaluated the sympathetic changes reflected by humeral artery blood flow, skin temperature and distal perfusion index. In the anatomical model the block was conducted without difficulties, showing an adequate periclavicular distribution of the contrast in the CT-scan and in sagittal sections, reaching the interscalenic space as far as the secondary trunks. Successful blocks were observed in 91% of patients after 25minutes. All the parameters reflecting sympathetic block increased significantly. The humeral artery blood flow showed an increase from 108 ± 86 to 188±141ml/min (P=.05), skin temperature from 32.1±2 to 32.8±9°C (P=.03) and perfusion index from 4±3 to 9±5 (P=.003). The medial approach of the ultrasound-guided costoclavicular block is anatomically feasible, with high clinical effectiveness using 20ml of 1.5% mepivacaine. The sympathetic block can be evaluated with all three parameters studied. Copyright © 2016 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.
"As a native nation, we must fight diabetes…"
... page please turn Javascript on. Feature: Diabetes Stories "As a native nation, we must fight diabetes…" Past ... you eat and exercise. Listen to your doctor. As a native nation, we need to fight diabetes, ...
Navigation of the autonomous vehicle reverse movement
NASA Astrophysics Data System (ADS)
Rachkov, M.; Petukhov, S.
2018-02-01
The paper presents a mathematical formulation of the vehicle reverse motion along a multi-link polygonal trajectory consisting of rectilinear segments interconnected by nodal points. Relevance of the problem is caused by the need to solve a number of tasks: to save the vehicle in the event of а communication break by returning along the trajectory already passed, to avoid a turn on the ground in constrained obstacles or dangerous conditions, or a partial return stroke for the subsequent bypass of the obstacle and continuation of the forward movement. The method of navigation with direct movement assumes that the reverse path is elaborated by using landmarks. To measure landmarks on board, a block of cameras is placed on a vehicle controlled by the operator through the radio channel. Errors in estimating deviation from the nominal trajectory of motion are determined using the multidimensional correlation analysis apparatus based on the dynamics of a lateral deviation error and a vehicle speed error. The result of the experiment showed a relatively high accuracy in determining the state vector that provides the vehicle reverse motion relative to the reference trajectory with a practically acceptable error while returning to the start point.
Walsh, Sophie D; Molcho, Michal; Craig, Wendy; Harel-Fisch, Yossi; Huynh, Quynh; Kukaswadia, Atif; Aasvee, Katrin; Várnai, Dora; Ottova, Veronika; Ravens-Sieberer, Ulrike; Pickett, William
2013-01-01
Then aims of the current study were 1) to provide cross-national estimates of the prevalence of physical fighting and weapon carrying among adolescents aged 11-15 years; (2) To examine the possible effects of physical fighting and weapon carrying on the occurrence of physical (medically treated injuries) and emotional health outcomes (multiple health complaints) among adolescents within the theoretical framework of Problem Behaviour Theory. 20,125 adolescents aged 11-15 in five countries (Belgium, Israel, USA, Canada, FYR Macedonia) were surveyed via the 2006 Health Behaviour in School Aged Children survey. Prevalence was calculated for physical fighting and weapon carrying along with physical and emotional measures that potentially result from violence. Regression analyses were used to quantify associations between violence/weapon carrying and the potential health consequences within each country. Large variations in fighting and weapon carrying were observed across countries. Boys reported more frequent episodes of fighting/weapon carrying and medically attended injuries in every country, while girls reported more emotional symptoms. Although there were some notable variations in findings between different participating countries, increased weapon carrying and physical fighting were both independently and consistently associated with more frequent reports of the potential health outcomes. Adolescents engaging in fighting and weapon carrying are also at risk for physical and emotional health outcomes. Involvement in fighting and weapon carrying can be seen as part of a constellation of risk behaviours with obvious health implications. Our findings also highlight the importance of the cultural context when examining the nature of violent behaviour for adolescents.
Walsh, Sophie D.; Molcho, Michal; Craig, Wendy; Harel-Fisch, Yossi; Huynh, Quynh; Kukaswadia, Atif; Aasvee, Katrin; Várnai, Dora; Ottova, Veronika; Ravens-Sieberer, Ulrike; Pickett, William
2013-01-01
Then aims of the current study were 1) to provide cross-national estimates of the prevalence of physical fighting and weapon carrying among adolescents aged 11–15 years; (2) To examine the possible effects of physical fighting and weapon carrying on the occurrence of physical (medically treated injuries) and emotional health outcomes (multiple health complaints) among adolescents within the theoretical framework of Problem Behaviour Theory. 20,125 adolescents aged 11–15 in five countries (Belgium, Israel, USA, Canada, FYR Macedonia) were surveyed via the 2006 Health Behaviour in School Aged Children survey. Prevalence was calculated for physical fighting and weapon carrying along with physical and emotional measures that potentially result from violence. Regression analyses were used to quantify associations between violence/weapon carrying and the potential health consequences within each country. Large variations in fighting and weapon carrying were observed across countries. Boys reported more frequent episodes of fighting/weapon carrying and medically attended injuries in every country, while girls reported more emotional symptoms. Although there were some notable variations in findings between different participating countries, increased weapon carrying and physical fighting were both independently and consistently associated with more frequent reports of the potential health outcomes. Adolescents engaging in fighting and weapon carrying are also at risk for physical and emotional health outcomes. Involvement in fighting and weapon carrying can be seen as part of a constellation of risk behaviours with obvious health implications. Our findings also highlight the importance of the cultural context when examining the nature of violent behaviour for adolescents. PMID:23437126
Shin, W; Mahmoud, S Y; Sakaie, K; Banks, S J; Lowe, M J; Phillips, M; Modic, M T; Bernick, C
2014-02-01
Traumatic brain injury is common in fighting athletes such as boxers, given the frequency of blows to the head. Because DTI is sensitive to microstructural changes in white matter, this technique is often used to investigate white matter integrity in patients with traumatic brain injury. We hypothesized that previous fight exposure would predict DTI abnormalities in fighting athletes after controlling for individual variation. A total of 74 boxers and 81 mixed martial arts fighters were included in the analysis and scanned by use of DTI. Individual information and data on fight exposures, including number of fights and knockouts, were collected. A multiple hierarchical linear regression model was used in region-of-interest analysis to test the hypothesis that fight-related exposure could predict DTI values separately in boxers and mixed martial arts fighters. Age, weight, and years of education were controlled to ensure that these factors would not account for the hypothesized effects. We found that the number of knockouts among boxers predicted increased longitudinal diffusivity and transversal diffusivity in white matter and subcortical gray matter regions, including corpus callosum, isthmus cingulate, pericalcarine, precuneus, and amygdala, leading to increased mean diffusivity and decreased fractional anisotropy in the corresponding regions. The mixed martial arts fighters had increased transversal diffusivity in the posterior cingulate. The number of fights did not predict any DTI measures in either group. These findings suggest that the history of fight exposure in a fighter population can be used to predict microstructural brain damage.
The Mind-Body Connection - How to Fight Stress and Ward Off Illness
... Issues The Mind-Body Connection How to Fight Stress and Ward Off Illness Past Issues / Winter 2008 ... system's ability to fight disease." Dangers of Chronic Stress Unhealthy levels of stress come in many guises. ...
RNA interference-based therapeutics: new strategies to fight infectious disease.
López-Fraga, M; Wright, N; Jiménez, A
2008-12-01
For many years, there has been an ongoing search for new compounds that can selectively alter gene expression as a new way to treat human disease by addressing targets that are otherwise "undruggable" with traditional pharmaceutical approaches involving small molecules or proteins. RNA interference (RNAi) strategies have raised a lot of attention and several compounds are currently being tested in clinical trials. Viruses are the obvious target for RNAi-therapy, as most are difficult to treat with conventional drugs, they become rapidly resistant to drug treatment and their genes differ substantially from human genes, minimizing side effects. Antisense strategy offers very high target specificity, i.e., any viral sequence could potentially be targeted using the complementary oligonucleotide sequence. Consequently, new antisense-based therapeutics have the potential to lead a revolution in the anti-infective drug development field. Additionally, the relatively short turnaround for efficacy testing of potential RNAi molecules and that any pathogen is theoretically amenable to rapid targeting, make them invaluable tools for treating a wide range of diseases. This review will focus on some of the current efforts to treat infectious disease with RNAi-based therapies and some of the obstacles that have appeared on the road to successful clinical intervention.
Obstacles to HIV prevention, treatment and care in selected public universities in South Africa.
Mbatha, Blessing
2014-09-01
South Africa, like the rest of Southern Africa, is ravaged by AIDS. Higher education in South Africa has a significant role to play in the fight against the spread of HIV and AIDS. This article reports the factors contributing to the spread of HIV and AIDS in three selected public universities in South Africa. To achieve the stated aim, the study answered the following research question: What are the factors contributing to the spread of HIV and AIDS in South African public universities? The problem in this study stems from South Africa's HIV and AIDS infection rate, one of the highest in the world, especially in KwaZulu-Natal. A qualitative approach was adopted by conducting focus group interviews with the students. The data were analysed using axial coding and open coding, where dominant themes from the discussions were identified and discussed in detail. The findings show that barriers to HIV and AIDS prevention, care and treatment exist in the tertiary institutions under study. Social and economic interventions are needed to stem the spread of HIV and AIDS at tertiary institutions. A range of recommendations for halting the spread of HIV and AIDS in these institutions is provided.
[The human right to adequate food: an urban vision].
Casemiro, Juliana Pereira; Valla, Victor Vincent; Guimarães, Maria Beatriz Lisboa
2010-07-01
The human right to adequate food is comprehended in two dimensions: being free of hunger and denutrition and having access to an adequate food. The urban context, in which the possession of food is done primarily through merchandising because of its strong consuming appealing, became a big challenge to debate this topic in poor districts today. Here we combine considerations of a qualitative study carried out in São João de Meriti, Rio de Janeiro State, joining leaders from Pastoral da Criança in focal group sessions. The unemployment, the sub-employment and the difficulty in reaching the public health system, the social assistance and basic sanitation were presented as the major obstacles to bring into effect the human right to food. It was possible to determine that, among the strategies to fight the poverty and hunger, a big highlight is the establishment of mutual help mechanisms. The social support, generosity and religiousness were presented as the most important categories among the thoughts of the leaders. Facing a reality in which poverty and hunger appear as something inherent or become a mechanism of change during elections, the issue of the clienteles appears as a huge concern and challenge for those leaders.
Bernick, Charles; Banks, Sarah J; Shin, Wanyong; Obuchowski, Nancy; Butler, Sam; Noback, Michael; Phillips, Michael; Lowe, Mark; Jones, Stephen; Modic, Michael
2015-01-01
Objectives Cumulative head trauma may alter brain structure and function. We explored the relationship between exposure variables, cognition and MRI brain structural measures in a cohort of professional combatants. Methods 224 fighters (131 mixed martial arts fighters and 93 boxers) participating in the Professional Fighters Brain Health Study, a longitudinal cohort study of licensed professional combatants, were recruited, as were 22 controls. Each participant underwent computerised cognitive testing and volumetric brain MRI. Fighting history including years of fighting and fights per year was obtained from self-report and published records. Statistical analyses of the baseline evaluations were applied cross-sectionally to determine the relationship between fight exposure variables and volumes of the hippocampus, amygdala, thalamus, caudate, putamen. Moreover, the relationship between exposure and brain volumes with cognitive function was assessed. Results Increasing exposure to repetitive head trauma measured by number of professional fights, years of fighting, or a Fight Exposure Score (FES) was associated with lower brain volumes, particularly the thalamus and caudate. In addition, speed of processing decreased with decreased thalamic volumes and with increasing fight exposure. Higher scores on a FES used to reflect exposure to repetitive head trauma were associated with greater likelihood of having cognitive impairment. Conclusions Greater exposure to repetitive head trauma is associated with lower brain volumes and lower processing speed in active professional fighters. PMID:25633832
“I Went to a Fight the Other Night and a Hockey Game Broke Out”
Goldschmied, Nadav; Espindola, Samantha
2013-01-01
Background: The current study explored the relationship between fighting behavior and passage of time, across games and seasons, in an attempt to assess if violent behavior in hockey is impulsive or intentional. Hypothesis: Before engaging in fighting behavior, players assess the utility of their actions and thus will fight less when the game is on the line (third period) and when champions are crowned (postseason). Methods: An archival exploration utilizing open access databases from multiple Internet sources. Results: During the 2010-2011 National Hockey League (NHL) season, players were significantly less likely to be involved in a fight as the game was coming to a close than in its early stages. In addition, data from the past 10 NHL seasons showed that players were significantly more violent in preseason games than during the regular season. They were also least likely to be involved in a fight during the postseason. Conclusion: The converging evidence suggests that players take into account the penalties associated with fighting and are less likely to engage in violence when the stakes are high, such as at the end of a game or a season. This implies, in turn, that major acts of aggression in the league are more likely to be calculated rather than impulsive. The findings suggest that a more punitive system should diminish fighting behavior markedly. PMID:24427418
Beiss, Veronique; Spiegel, Holger; Boes, Alexander; Kapelski, Stephanie; Scheuermayer, Matthias; Edgue, Gueven; Sack, Markus; Fendel, Rolf; Reimann, Andreas; Schillberg, Stefan; Pradel, Gabriele; Fischer, Rainer
2015-07-01
Malaria is a vector-borne disease affecting more than two million people and accounting for more than 600,000 deaths each year, especially in developing countries. The most serious form of malaria is caused by Plasmodium falciparum. The complex life cycle of this parasite, involving pre-erythrocytic, asexual and sexual stages, makes vaccine development cumbersome but also offers a broad spectrum of vaccine candidates targeting exactly those stages. Vaccines targeting the sexual stage of P. falciparum are called transmission-blocking vaccines (TBVs). They do not confer protection for the vaccinated individual but aim to reduce or prevent the transmission of the parasite within a population and are therefore regarded as an essential tool in the fight against the disease. Malaria predominantly affects large populations in developing countries, so TBVs need to be produced in large quantities at low cost. Combining the advantages of eukaryotic expression with a virtually unlimited upscaling potential and a good product safety profile, plant-based expression systems represent a suitable alternative for the production of TBVs. We report here the high level (300 μg/g fresh leaf weight (FLW)) transient expression in Nicotiana benthamiana leaves of an effective TBV candidate based on a fusion protein F0 comprising Pfs25 and the C0-domain of Pfs230, and the implementation of a simple and cost-effective heat treatment step for purification that yields intact recombinant protein at >90% purity with a recovery rate of >70%. The immunization of mice clearly showed that antibodies raised against plant-derived F0 completely blocked the formation of oocysts in a malaria transmission-blocking assay (TBA) making F0 an interesting TBV candidate or a component of a multi-stage malaria vaccine cocktail. © 2015 Wiley Periodicals, Inc.
Papakosta, Marianthi; Dalle, Carine; Haythornthwaite, Alison; Cao, Lishuang; Stevens, Edward B; Burgess, Gillian; Russell, Rachel; Cox, Peter J; Phillips, Stephen C; Grimm, Christian
2011-11-11
The capsaicin-, heat-, and proton-activated ion channel TRPV1, a member of the transient receptor potential cation channel family is a polymodal nociceptor. For almost a decade, TRPV1 has been explored by the pharmaceutical industry as a potential target for example for pain conditions. Antagonists which block TRPV1 activation by capsaicin, heat, and protons were developed by a number of pharmaceutical companies. The unexpected finding of hyperthermia as an on-target side effect in clinical studies using polymodal TRPV1 antagonists has prompted companies to search for ways to circumvent hyperthermia, for example by the development of modality-selective antagonists. The significant lack of consistency of the pharmacology of many TRPV1 antagonists across different species has been a further obstacle. JYL-1421 for example was shown to block capsaicin and heat responses in human and monkey TRPV1 while it was largely ineffective in blocking heat responses in rat TRPV1. These findings suggested structural dissimilarities between different TRPV1 species relevant for small compound antagonism for example of heat activation. Using a chimeric approach (human and rat TRPV1) in combination with a novel FLIPR-based heat activation assay and patch-clamp electrophysiology we have identified the pore region as being strongly linked to the observed species differences. We demonstrate that by exchanging the pore domains JYL-1421, which is modality-selective in rat can be made modality-selective in human TRPV1 and vice-versa.
Brownscombe, Jacob W; Marchand, Kelsey; Tisshaw, Kathryn; Fewster, Victoria; Groff, Olivia; Pichette, Melissa; Seed, Marian; Gutowsky, Lee F G; Wilson, Alexander D M; Cooke, Steven J
2014-01-01
Release of fish captured by recreational anglers is a common practice due to angler conservation ethics or compliance with fisheries regulations. As such, there is a need to understand the factors that influence mortality and sub-lethal impairments to ensure that catch-and-release angling is a sustainable practice. Longer angling times generally contribute to increased stress and mortality in fish such that reducing these times putatively reduces stress and improves survival. However, the relative importance of fight intensity (rather than simply duration) on fish condition is poorly understood. The objective of this research was to examine the effects of fight intensity on physiological stress and reflex impairment of largemouth bass (Micropterus salmoides). The largemouth bass were angled using conventional recreational fishing gear in May (water temperature ∼12°C) and June (∼22°C) of 2014 in Lake Opinicon, Ontario, Canada. Fight intensity was quantified using tri-axial accelerometer loggers mounted on the tips of fishing rods. Upon capture, reflex impairment measures were assessed, and fish were held for 1 h prior to blood sampling for measurement of physiological stress (blood glucose and lactate concentrations and pH). Physiological stress values showed a negative trend with fight duration and total fight intensity, but a positive trend with average fight intensity. Water temperature emerged as the most important predictor of the stress response in largemouth bass, while fight duration and intensity were not strong predictors. Reflex impairment was minimal, but higher reflex impairment scores were associated with elevated blood glucose. Overall, the findings of this study suggest that angling for largemouth bass at colder temperatures (<15°C) causes greater physiological stress than at warmer temperatures (>20°C). Based on our findings, we conclude that fight intensity is likely not to be a major driver of physiological stress in this species using typical largemouth bass angling gear, owing to the relatively short fight times (i.e. <2 min).
Groothuis, Ton G G; McManus, I C; Schaafsma, Sara M; Geuze, Reint H
2013-06-01
The strong population bias in hand preference in favor of right-handedness seems to be a typical human trait. An elegant evolutionary hypothesis explaining this trait is the so-called fighting hypothesis that postulates that left-handedness is under frequency-dependent selection. The fighting hypothesis assumes that left-handers, being in the minority because of health issues, are still maintained in the population since they would have a greater chance of winning in fights than right-handers due to a surprise effect. This review critically evaluates the assumptions and evidence for this hypothesis and concludes that some evidence, although consistent with the fighting hypothesis, does not directly support it and may also be interpreted differently. Other supportive data are ambiguous or open for both statistical and theoretical criticism. We conclude that, presently, evidence for the fighting hypothesis is not particularly strong, but that there is little evidence to reject it either. The hypothesis thus remains an intuitively plausible explanation for the persistent left-hand preference in the population. We suggest alternative explanations and several ways forward for obtaining more crucial data for testing this frequently cited hypothesis. © 2013 New York Academy of Sciences.
Serious fighting-related injuries produce a significant reduction in intelligence.
Schwartz, Joseph A; Beaver, Kevin M
2013-10-01
Fighting-related injuries are common among adolescents within the United States, but how such injuries relate to subsequent cognitive functioning remains unclear. In particular, the long-term effect of fighting-related injuries suffered during important developmental periods, such as adolescence, on subsequent cognitive functioning has been overlooked by previous studies. The purpose of this study is to examine the association between sustaining serious fighting-related injuries and changes in verbal intelligence (IQ) over a 5- to 6-year time period. Longitudinal multivariate statistical models were used to analyze data from the National Longitudinal Study of Adolescent Health collected between 1994 and 2002 and analyzed in 2013. Even a single fighting-related injury resulted in a significant reduction in IQ over time even after controlling for age, race, sex, and changes in socioeconomic status (SES) over the study period. Additionally, females experienced a significantly greater reduction in IQ from each fighting-related injury than males. Fighting-related injuries have a significant impact on subsequent cognitive functioning and intelligence. The implications for future policies and research are discussed in more detail. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
Trends in Fighting and Violence Among Adolescents in the United States, 2002–2014
Nelson, Erik J.; Vaughn, Michael G.; Reingle Gonzalez, Jennifer M.; Córdova, David
2017-01-01
Objectives. To examine trends in and correlates of fighting and violence among youths from the 3 largest racial/ethnic groups in the United States. Methods. We derived race/ethnicity-specific prevalence estimates for fighting, group fighting, and attacks with intent to harm from the National Survey on Drug Use and Health, a population-based study of youths aged 12 to 17 years. Results. The prevalence of youth fighting and violence decreased significantly in all racial/ethnic groups over the study period (2002–2014), dropping from a high of 33.6% in 2003 to a low of 23.7% in 2014, reflecting a 29% decrease in the relative proportion of young people involved in these behaviors. However, there was also a clear severity gradient in which year-by-year point estimates for fighting and violence were consistently highest among non-Hispanic African American youths, followed by Hispanic and then non-Hispanic White youths. Conclusions. Although fighting and violence are on the decline among young people in general and across racial/ethnic subgroups, there is a stable pattern of disparities in youth involvement in these behaviors. PMID:28426317
1995-01-01
FURTHER ACTION DECISION UNDER CERCLAI STUDY AREA 31 MOORE ARMY AIRFIELD FIRE FIGHTING TRAINING AREA FORT DEVENS , MASSACHUSETFS TABLE OF CONTENTS jSection...Inc. 31DD.DOC 6917.11 111,, NO FURTHER ACTION DECISION UNDER CERCLA I STUDY AREA 31 MOORE ARMY AIRFIELD FIRE FIGHTING TRAINING AREA 3 FORT DEVENS ...Fire Fighting Training Area) at Fort Devens , Massachusetts, have resulted in the decision that no further studies or remediation are required at this
Nightlife, verbal and physical violence among young European holidaymakers: what are the triggers?
Calafat, A; Bellis, M A; Fernández Del Rio, E; Juan, M; Hughes, K; Morleo, M; Becoña, E; Duch, M; Stamos, A; Mendes, F
2013-10-01
There is an established relationship between nightlife, substance use and violence. This study investigated this relationship when people are on holiday, and explored the differences in experiences between physical and verbal violence. A survey of young tourists at seven airport departure areas in Southern European resorts. Questionnaires from 6502 British and German tourists were analysed exploring demographics, violence (verbal and physical), substance use, and reasons for resort and venue selection. Over two-thirds of respondents reported being drunk on their holiday, 12.4% had been involved in arguments and 2.9% had been involved in fights. Logistic regression highlighted more violence amongst visitors to Mallorca [arguments: adjusted odds ratio (AOR) 2.7; fights: AOR 2.0] compared with those visiting Portugal, males (arguments: AOR 1.3; fights: AOR 1.7), those who had used illicit drugs (arguments: AOR 1.5; fights: AOR 2.9), those who had been in fights at home in the last 12 months (arguments: AOR 2.2; fights AOR 2.9), and those who had frequently been drunk abroad (arguments: AOR 2.4; fights: AOR 2.5). Those aged 16-19 years, visiting Italy or Crete, who were drunk for fewer than half of the days of their stay, and who chose bars because they were frequented by drunk people were more likely to report having an argument. Fights were associated with cannabis use and were negatively associated with choosing bars with a friendly atmosphere. Economic status or frequency of visiting bars had no relationship with arguments or fights. Understanding and addressing the variables involved in violence when holidaying abroad is critical in targeting appropriate health promotion and harm reduction measures. Copyright © 2013 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Veenendaal, Andreas K J; Sundin, Charlotta; Blocker, Ariel J
2009-01-01
Type III secretion systems (T3SSs) are essential virulence devices for many gram-negative bacteria that are pathogenic for plants, animals, and humans. They serve to translocate virulence effector proteins directly into eukaryotic host cells. T3SSs are composed of a large cytoplasmic bulb and a transmembrane region into which a needle is embedded, protruding above the bacterial surface. The emerging antibiotic resistance of bacterial pathogens urges the development of novel strategies to fight bacterial infections. Therapeutics that rather than kill bacteria only attenuate their virulence may reduce the frequency or progress of resistance emergence. Recently, a group of salicylidene acylhydrazides were identified as inhibitors of T3SSs in Yersinia, Chlamydia, and Salmonella species. Here we show that these are also effective on the T3SS of Shigella flexneri, where they block all related forms of protein secretion so far known, as well as the epithelial cell invasion and induction of macrophage apoptosis usually demonstrated by this bacterium. Furthermore, we show the first evidence for the detrimental effect of these compounds on T3SS needle assembly, as demonstrated by increased numbers of T3S apparatuses without needles or with shorter needles. Therefore, the compounds generate a phenocopy of T3SS export apparatus mutants but with incomplete penetrance. We discuss why this would be sufficient to almost completely block the later secretion of effector proteins and how this begins to narrow the search for the molecular target of these compounds.
Fighting detection using interaction energy force
NASA Astrophysics Data System (ADS)
Wateosot, Chonthisa; Suvonvorn, Nikom
2017-02-01
Fighting detection is an important issue in security aimed to prevent criminal or undesirable events in public places. Many researches on computer vision techniques have studied to detect the specific event in crowded scenes. In this paper we focus on fighting detection using social-based Interaction Energy Force (IEF). The method uses low level features without object extraction and tracking. The interaction force is modeled using the magnitude and direction of optical flows. A fighting factor is developed under this model to detect fighting events using thresholding method. An energy map of interaction force is also presented to identify the corresponding events. The evaluation is performed using NUSHGA and BEHAVE datasets. The results show the efficiency with high accuracy regardless of various conditions.
Brief report: Play fighting to curb self-reported aggression in young adolescents.
Carraro, Attilio; Gobbi, Erica; Moè, Angelica
2014-12-01
This study investigated the effects of play fighting on aggressive behaviors. It was hypothesized that the teaching of play fighting during physical education lessons could reduce self-reported aggression in a group of adolescents to a greater extent than playing volleyball (a low physical contact activity). Participants were 210 young adolescents (mean age = 13.27, SD = 0.48 years) from 10 classrooms that were randomly assigned to an 8-lesson play fighting session or to traditional volleyball lessons. They filled in the 12-item short version of the Aggression Questionnaire (AQ-12) pre- and post-interventions. The play fighting group showed a significant reduction in all the four subscales of the AQ-12 (Cohen d ranging from 0.61 to 0.67), while participants in the volleyball group did not. Results suggest that play fighting might provide useful contents in a physical education curriculum, with possible reduction in aggressive behavior. Copyright © 2014 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Thouret, Jean-Claude; Gupta, Avijit; Liew, Soo Chin; Lube, Gert; Cronin, Shane J.; Surono, Dr
2010-05-01
On 16 June 2006 an overpass of IKONOS coincided with the emplacement of an active block-and-ash flow fed by a lava dome collapse event at Merapi Volcano (Java, Indonesia). This was the first satellite image recorded for a moving pyroclastic flow. The very high-spatial resolution data displayed the extent and impact of the pyroclastic deposits emplaced during and prior to, the day of image acquisition. This allowed a number of features associated with high-hazard block-and-ash flows emplaced in narrow, deep gorges to be mapped, interpreted and understood. The block-and-ash flow and surge deposits recognized in the Ikonos images include: (1) several channel-confined flow lobes and tongues in the box-shaped valley; (2) thin ash-cloud surge deposit and knocked-down trees in constricted areas on both slopes of the gorge; (3) fan-like over bank deposits on the Gendol-Tlogo interfluves from which flows were re-routed in the Tlogo secondary valley; (4) massive over bank lobes on the right bank from which flows devastated the village of Kaliadem 0.5 km from the main channel, a small part of this flow being re-channeled in the Opak secondary valley. The high-resolution IKONOS images also helped us to identify geomorphic obstacles that enabled flows to ramp and spill out from the sinuous channel, a process called flow avulsion. Importantly, the avulsion redirected flows to unexpected areas away from the main channel. In the case of Merapi we see that the presence of valley fill by previous deposits, bends and man-made dams influence the otherwise valley-guided course of the flows. Sadly, Sabo dams (built to ameliorate the effect of high sediment load streams) can actually cause block-and-ash flows to jump out of their containing channel and advance into sensitive areas. Very-high-spatial resolution satellite images are very useful for mapping and interpreting the distribution of freshly erupted volcanic deposits. IKONOS-type images with 1-m resolution provide opportunities to study and map the meter-scale detail of volcanic deposits. When such high-spatial-resolution satellite remote sensing data are combined with in situ field work, geomorphic analyses can be applied that allow us to more fully understand the dynamics and hazards of eruptions. In the case given here, IKONOS imagery allowed two qualitative hazard assessments for block-and-ash flow activity in drainages around Merapi. Firstly, the interpretation of IKONOS images provides insights in factors that control the propagation of secondary flows as the avulsion of the main flows is driven by longitudinal change in channel capacity due to increased sinuosity in the valley and decreased containment space. Secondly, the sinuosity and obstacles (including Sabo dams) may create over bank flows over adjacent low relief, allowing them to reach unexpectedly vulnerable areas distant from an active dome and away from the volcanically active valleys. Hazard assessment should therefore consider the geometry of secondary channels outside the principal valleys.
NASA Astrophysics Data System (ADS)
Rusconi, Francisco Jose
A series of Plio-Pleistocene mass transport deposits (MTD) have been identified in the deepwater Taranaki Basin, in New Zealand, using the Romney 3D seismic survey, which covers an area of approximately 2000 km2. One of these MTDs has been chosen for description and interpretation based on high confidence mapping of its boundary surfaces. The deposit exhibits an array of interesting features similar to those documented by researchers elsewhere plus a unique basal feature unlike those previously observed. The basal shear surface exhibits erosional features such as grooves, "monkey fingers", and glide tracks. Internally, the MTD is typically characterized by low impedance, chaotic, semi-transparent reflectors surrounding isolated coherent packages of seismic facies interpreted as intact blocks rafted within the mass transport complex. Distally, the deposit presents outrunner blocks and pressure ridges. The new element described in this work consists of a composite feature that includes a protruding obstacle ("shield block") on the paleo-seafloor that acted as a barrier to subsequent flows as they advanced downslope. These blocks disrupt the incoming flow and result in elongate, downflow negative features ("erosional shadow scours"), which are then infilled by the mass transport deposit, and are preserved as elongate isochore thicks. Kinematic evidence provided by various structures suggests that the MTD flow direction was SE-NW toward bathyal depths. The features presented and the absence of extensional headwall structures, such as local arcuate glide planes and rotated slide blocks, suggest that this part of the deposit belongs to the translational to distal domain of the MTD, and its source area is expected to be somewhere toward the SE in a paleo continental slope.
Jameson, Jason; Pappa, Leon; McGuire, Brian; Kelly, Karen R
2015-01-01
For decades women have been restricted from direct assignment to certain military occupational specialties such as infantry. These restrictions can limit the advancement of women through the ranks of military leadership. Thus, the purpose of this effort was to identify those physical requirements most likely to serve as barriers for women wanting to enter closed combat arms positions, and to evaluate the quality of existing physical fitness tests as potential measures of assessment of combat readiness. Data were collected from 3 different sites within the US Marine Corps Training and Education Command. All participants (409 male, 379 femaile) were active-duty Marines who recently completed the Physical Fitness Test (PFT) and Combat Fitness Test (CFT). Participants completed 6 physical tasks: 120-mm tank loading drill, 155-mm artillery round carry, negotiating an obstacle course wall while wearing a fighting load (≈30 lb), pull-ups, deadlift, and clean and press. Overall, there was a high rate of successful completion on the combat proxy tasks (men, ≈80% to 100%; women, ≈70% to 100%), with the notable exception being the clean and press (men, 80%; women, 9%) and pull-ups (men, 16±4; women, 4±2). The PFT and CFT components tasks were also related, strongly in some cases, with performance on combat-related proxy tasks (Spearman's ρ typically ranged from 0.60 to 0.80). Estimates of fat-free mass and VO2max were also strongly related to an overall measure of combat readiness (Spearman's ρ=0.77 and ρ=0.56, respectively). The primary physical obstacle for women is upper body strength. However, some women could successfully complete all of the proxy tasks and thus are physically capable of meeting the demands of closed combat occupations. The fact that some female Marines could complete the most challenging upper body strength tasks suggests that these barriers are not inherent but may be due to a lack of training specificity.
46 CFR 109.223 - Fire fighting equipment.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Fire fighting equipment. 109.223 Section 109.223 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Tests, Drills, and Inspections § 109.223 Fire fighting equipment. The master or person in charge...
46 CFR 109.223 - Fire fighting equipment.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 4 2013-10-01 2013-10-01 false Fire fighting equipment. 109.223 Section 109.223 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Tests, Drills, and Inspections § 109.223 Fire fighting equipment. The master or person in charge...
46 CFR 109.223 - Fire fighting equipment.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 4 2014-10-01 2014-10-01 false Fire fighting equipment. 109.223 Section 109.223 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Tests, Drills, and Inspections § 109.223 Fire fighting equipment. The master or person in charge...
46 CFR 109.223 - Fire fighting equipment.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 4 2011-10-01 2011-10-01 false Fire fighting equipment. 109.223 Section 109.223 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Tests, Drills, and Inspections § 109.223 Fire fighting equipment. The master or person in charge...
46 CFR 109.223 - Fire fighting equipment.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 4 2012-10-01 2012-10-01 false Fire fighting equipment. 109.223 Section 109.223 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Tests, Drills, and Inspections § 109.223 Fire fighting equipment. The master or person in charge...
75 FR 221 - Airworthiness Directives; Fire Fighting Enterprises Limited Portable Halon 1211 Fire...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-05
... Airworthiness Directives; Fire Fighting Enterprises Limited Portable Halon 1211 Fire Extinguishers as Installed... specification, have been supplied to the aviation industry for use in fire extinguishing equipment. * * * * * * * * * * * This Halon 1211 has subsequently been used to fill certain FFE [Fire Fighting Enterprises] portable...
School Violence: Social Bond Theory and Physical Fights
ERIC Educational Resources Information Center
Nemmetz, Amy J.
2010-01-01
Physical fighting in school is a concern for school administrators, juvenile justice professionals, and students. This quantitative study examined the involvement of physical fights at school among 5,674 adolescents across the United States via a casual comparative design with a correlational subcomponent. Differences were discovered between…
Take-over performance in evasive manoeuvres.
Happee, Riender; Gold, Christian; Radlmayr, Jonas; Hergeth, Sebastian; Bengler, Klaus
2017-09-01
We investigated after effects of automation in take-over scenarios in a high-end moving-base driving simulator. Drivers performed evasive manoeuvres encountering a blocked lane in highway driving. We compared the performance of drivers 1) during manual driving, 2) after automated driving with eyes on the road while performing the cognitively demanding n-back task, and 3) after automated driving with eyes off the road performing the visually demanding SuRT task. Both minimum time to collision (TTC) and minimum clearance towards the obstacle disclosed a substantial number of near miss events and are regarded as valuable surrogate safety metrics in evasive manoeuvres. TTC proved highly sensitive to the applied definition of colliding paths, and we prefer robust solutions using lane position while disregarding heading. The extended time to collision (ETTC) which takes into account acceleration was close to the more robust conventional TTC. In line with other publications, the initial steering or braking intervention was delayed after using automation compared to manual driving. This resulted in lower TTC values and stronger steering and braking actions. Using automation, effects of cognitive distraction were similar to visual distraction for the intervention time with effects on the surrogate safety metric TTC being larger with visual distraction. However the precision of the evasive manoeuvres was hardly affected with a similar clearance towards the obstacle, similar overshoots and similar excursions to the hard shoulder. Further research is needed to validate and complement the current simulator based results with human behaviour in real world driving conditions. Experiments with real vehicles can disclose possible systematic differences in behaviour, and naturalistic data can serve to validate surrogate safety measures like TTC and obstacle clearance in evasive manoeuvres. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Obstacles to reduction in infantile developmental dysplasia of the hip
Studer, K.; Williams, N.; Studer, P.; Baker, M.; Glynn, A.; Foster, B. K.; Cundy, P. J.
2017-01-01
Abstract Purpose Identification of anatomical structures that block reduction in developmental dysplasia of the hip (DDH) is important for the management of this challenging condition. Obstacles to reduction seen on arthrogram are well-known. However, despite the increasing use of MRI in the assessment of adequacy of reduction in DDH, the interpretation of MRI patho-anatomy is ill-defined with a lack of relevant literature to guide clinicians. Method This is a retrospective analysis of the MRI of patients with DDH treated by closed reduction over a five-year period (between 2009 and 2014). Neuromuscular and genetic disorders were excluded. Each MRI was analysed by two orthopaedic surgeons and a paediatric musculoskeletal radiologist to identify the ligamentum teres, pulvinar, transverse acetabular ligament (TAL), capsule, labrum and acetabular roof cartilage hypertrophy. Inter- and intraobserver reliability was calculated. The minimum follow-up was 12 months. Results A total of 29 patients (38 hips) underwent closed reduction for treatment of DDH. Eight hips showed persistent subluxation on post-operative MRI. Only three of these eight hips showed an abnormality on arthrogram. The pulvinar was frequently interpreted as ‘abnormal’ on MRI. The main obstacles identified on MRI were the ligamentum teres (15.8%), labrum (13.1%) and acetabular roof cartilage hypertrophy (13.2%). The inter-rater reliability was good for TAL, capsule and pulvinar; moderate for ligamentum teres and labrum; and poor for hypertrophied cartilage. Conclusion The labrum, ligamentum teres and acetabular roof cartilage hypertrophy are the most important structures seen on MRI preventing complete reduction of DDH. Focused interpretation of these structures may assist in the management of DDH. PMID:29081850
Gupta, Rahul
2018-01-01
AMPA receptors (AMPARs) and their associations with auxiliary transmembrane proteins are bulky structures with large steric-exclusion volumes. Hence, self-crowding of AMPARs, depending on the local density, may affect their lateral diffusion in the postsynaptic membrane as well as in the highly crowded postsynaptic density (PSD) at excitatory synapses. Earlier theoretical studies considered only the roles of transmembrane obstacles and the AMPAR-binding submembranous scaffold proteins in shaping receptor diffusion within PSD. Using lattice model of diffusion, the present study investigates the additional impacts of self-crowding on the anomalousity and effective diffusion coefficient (Deff) of AMPAR diffusion. A recursive algorithm for avoiding false self-blocking during diffusion simulation is also proposed. The findings suggest that high density of AMPARs in the obstacle-free membrane itself engenders strongly anomalous diffusion and severe decline in Deff. Adding transmembrane obstacles to the membrane accentuates the anomalousity arising from self-crowding due to the reduced free diffusion space. Contrarily, enhanced AMPAR-scaffold binding, either through increase in binding strength or scaffold density or both, ameliorates the anomalousity resulting from self-crowding. However, binding has differential impacts on Deff depending on the receptor density. Increase in binding causes consistent decrease in Deff for low and moderate receptor density. For high density, binding increases Deff as long as it reduces anomalousity associated with intense self-crowding. Given a sufficiently strong binding condition when diffusion acquires normal behavior, further increase in binding causes decrease in Deff. Supporting earlier experimental observations are mentioned and implications of present findings to the experimental observations on AMPAR diffusion are also drawn. PMID:29444074
2015-09-01
OPTICAL FLOW SENSORS FOR DEAD RECKONING, HEADING REFERENCE, OBSTACLE DETECTION, AND OBSTACLE AVOIDANCE by Tarek M. Nejah September 2015...SENSORS FOR DEAD RECKONING, HEADING REFERENCE, OBSTACLE DETECTION, AND OBSTACLE AVOIDANCE 5. FUNDING NUMBERS 6. AUTHOR(S) Nejah, Tarek M. 7...DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) A novel approach for dead reckoning, heading reference, obstacle detection, and obstacle
ERIC Educational Resources Information Center
DuBose, Cornelius B.
2004-01-01
E-mail has become a significant means of communication between teachers, students, parents and administrators in many school systems. The increasing amount of SPAM e-mail threatens to overload school email systems. The experience of Lake Forest, IL School District #67 in fighting e-mail spam is described. Spam basics, spam fighting tools, and…
14 CFR 91.815 - Agricultural and fire fighting airplanes: Noise operating limitations.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Agricultural and fire fighting airplanes... RULES Operating Noise Limits § 91.815 Agricultural and fire fighting airplanes: Noise operating limitations. (a) This section applies to propeller-driven, small airplanes having standard airworthiness...
14 CFR 91.815 - Agricultural and fire fighting airplanes: Noise operating limitations.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Agricultural and fire fighting airplanes... RULES Operating Noise Limits § 91.815 Agricultural and fire fighting airplanes: Noise operating limitations. (a) This section applies to propeller-driven, small airplanes having standard airworthiness...
14 CFR 91.815 - Agricultural and fire fighting airplanes: Noise operating limitations.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Agricultural and fire fighting airplanes... RULES Operating Noise Limits § 91.815 Agricultural and fire fighting airplanes: Noise operating limitations. (a) This section applies to propeller-driven, small airplanes having standard airworthiness...
14 CFR 91.815 - Agricultural and fire fighting airplanes: Noise operating limitations.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Agricultural and fire fighting airplanes... RULES Operating Noise Limits § 91.815 Agricultural and fire fighting airplanes: Noise operating limitations. (a) This section applies to propeller-driven, small airplanes having standard airworthiness...
ERIC Educational Resources Information Center
The Journal of State Government, 1990
1990-01-01
All nine articles in this periodical issue focus on the theme of the war against illegal drug use, approaching the topic from a variety of perspectives. The articles are: "The Drug War: Meeting the Challenge" (Stanley E. Morris); "Ways to Fight Drug Abuse" (Bruce A. Feldman); "Treatment Key to Fighting Drugs" (Stan…
Federal Register 2010, 2011, 2012, 2013, 2014
2012-11-23
... Equipment, Training and Drills Onboard Offshore Facilities and Mobile Offshore Drilling Units (MODUs... lifesaving and fire-fighting equipment, training and drills on board offshore facilities and MODUs operating... guidance concerning lifesaving and fire-fighting equipment, training, and drills onboard manned offshore...
46 CFR 167.45-30 - Use of approved fire-fighting equipment.
Code of Federal Regulations, 2010 CFR
2010-10-01
... PUBLIC NAUTICAL SCHOOL SHIPS Special Firefighting and Fire Prevention Requirements § 167.45-30 Use of approved fire-fighting equipment. Portable fire extinguishers or fire-extinguishing systems which conform... 46 Shipping 7 2010-10-01 2010-10-01 false Use of approved fire-fighting equipment. 167.45-30...
Stepping over obstacles: gait patterns of healthy young and old adults.
Chen, H C; Ashton-Miller, J A; Alexander, N B; Schultz, A B
1991-11-01
Falls associated with tripping over an obstacle can be devastating to elderly individuals, yet little is known about the strategies used for stepping over obstacles by either old or young adults. The gait of gender-matched groups of 24 young and 24 old healthy adults (mean ages 22 and 71 years) was studied during a 4 m approach to and while stepping over obstacles of 0, 25, 51, or 152 mm height and in level obstacle-free walking. Optoelectronic cameras and recorders were used to record approach and obstacle crossing speeds as well as bilateral lower extremity kinematic parameters that described foot placement and movement trajectories relative to the obstacle. The results showed that age had no effect on minimum swing foot clearance (FC) over an obstacle. For the 25 mm obstacle, mean FC was 64 mm, or approximately three times that used in level gait; FC increased nonlinearly with obstacle height for all subjects. Although no age differences were found in obstacle-free gait, old adults exhibited a significantly more conservative strategy when crossing obstacles, with slower crossing speed, shorter step length, and shorter obstacle-heel strike distance. In addition, the old adults crossed the obstacle so that it was 10% further forward in their obstacle-crossing step. Although all subjects successfully avoided the riskiest form of obstacle contact, tripping, 4/24 healthy old adults stepped on an obstacle, demonstrating an increased risk for obstacle contact with age.
A health systems constraints analysis for neurologic diseases: the example of Timor-Leste.
Mateen, Farrah J; Martins, Nelson
2014-04-08
Neurologic care exists within health systems and complex social, political, and economic environments. Identification of obstacles within health systems, defined as "constraints," is crucial to improving the delivery of neurologic care within its macroclimate. Here we use the World Health Organization's 6 building blocks of a health system to examine core services for priority interventions related to neurologic disease: (1) service delivery; (2) health workforce; (3) information; (4) medical products, vaccines, and technologies; (5) financing; and (6) leadership and governance. We demonstrate the use of a constraints analysis for neurologic disorders using the example of Timor-Leste, a newly sovereign and low-income country, which aims to improve neurologic care in the coming years.
Challenging Roadblocks to Cancer Cure.
Loda, Massimo
2016-09-01
The Pezcoller Symposium in Trento, Italy, June 2015, focused entirely on the question of why advanced cancer cure is so uncommon despite the extraordinarily rapid growth of invaluable therapeutic information. Participants were asked to define and to critically evaluate real and potential obstacles to permanent disease eradication. High-level concepts on potential road blocks to cures as well as opportunities for intervention in diverse areas of investigation ranging from genomic alterations to metabolism, microenvironment, immunity, and mechanotransduction were discussed. Provocative concepts and novel therapeutic avenues were proposed. What follows is a critical analysis of the highlights of this meeting. Cancer Res; 76(17); 4924-30. ©2016 AACR. ©2016 American Association for Cancer Research.
Rapidly accelerating Mathieu and Weber surface plasmon beams.
Libster-Hershko, Ana; Epstein, Itai; Arie, Ady
2014-09-19
We report the generation of two types of self-accelerating surface plasmon beams which are solutions of the nonparaxial Helmholtz equation in two dimensions. These beams preserve their shape while propagating along either elliptic (Mathieu beam) or parabolic (Weber beam) trajectories. We show that owing to the nonparaxial nature of the Weber beam, it maintains its shape over a much larger distance along the parabolic trajectory, with respect to the corresponding solution of the paraxial equation-the Airy beam. Dynamic control of the trajectory is realized by translating the position of the illuminating free-space beam. Finally, the ability of these beams to self-heal after blocking obstacles is demonstrated as well.
Prevalence and associated factors of physical fighting among school-going adolescents in Namibia
Rudatsikira, Emmanuel; Siziya, Seter; Kazembe, Lawrence N; Muula, Adamson S
2007-01-01
Background Interpersonal physical violence is an important global public health concern that has received limited attention in the developing world. There is in particular a paucity of data regarding physical violence and its socio-demographic correlates among in-school adolescents in Namibia. Methods We analysed cross-sectional data from the Namibia Global School-Based Health Survey (GSHS) conducted in 2004. We aimed to estimate the prevalence and socio-demographic correlates of physical fighting within the last 12 months. We obtained frequencies of socio-demographic attributes. We also assessed the association between self-reported history of having engaging in a physical fight and a selected list of independent variables using logistic regression analysis. Results Of the 6283 respondents, 50.6% (55.2% males and 46.2% females) reported having been in a physical fight in the past 12 months. Males were more likely to have been in a physical fight than females (OR = 1.71, 95% CI (1.44, 2.05)). Smoking, drinking alcohol, using drugs and bullying victimization were positively associated with fighting (OR = 1.91, 95% CI (1.49, 2.45); OR = 1.48, 95% CI (1.21, 1.81); OR = 1.55, 95% CI (1.22, 1.81); and OR = 3.12, 95% CI (2.62, 3.72), respectively). Parental supervision was negatively associated with physical fighting (OR = 0.82, 95% CI (0.69, 0.98)). Both male and female substance users (cigarette smoking, alcohol and drug use) were more likely to engage in physical fighting than non-substance users (OR = 3.53, 95% CI (2.60, 4.81) for males and OR = 11.01, 95% CI (7.25, 16.73) for females). Parental supervision was negatively associated with physical fighting (OR = 0.85, 95% CI (0.72, 0.99)). Conclusion Prevalence of physical fighting within the last 12 months was comparable to estimates obtained in European countries. We also found clustering of problem behaviours or experiences among adolescents who reported having engaged in physical violence in the past 12 months. There is a need to bring adolescent violent behaviour to the fore of the public health agenda in Namibia. PMID:17650328
Brownscombe, Jacob W.; Marchand, Kelsey; Tisshaw, Kathryn; Fewster, Victoria; Groff, Olivia; Pichette, Melissa; Seed, Marian; Gutowsky, Lee F. G.; Wilson, Alexander D. M.; Cooke, Steven J.
2014-01-01
Release of fish captured by recreational anglers is a common practice due to angler conservation ethics or compliance with fisheries regulations. As such, there is a need to understand the factors that influence mortality and sub-lethal impairments to ensure that catch-and-release angling is a sustainable practice. Longer angling times generally contribute to increased stress and mortality in fish such that reducing these times putatively reduces stress and improves survival. However, the relative importance of fight intensity (rather than simply duration) on fish condition is poorly understood. The objective of this research was to examine the effects of fight intensity on physiological stress and reflex impairment of largemouth bass (Micropterus salmoides). The largemouth bass were angled using conventional recreational fishing gear in May (water temperature ∼12°C) and June (∼22°C) of 2014 in Lake Opinicon, Ontario, Canada. Fight intensity was quantified using tri-axial accelerometer loggers mounted on the tips of fishing rods. Upon capture, reflex impairment measures were assessed, and fish were held for 1 h prior to blood sampling for measurement of physiological stress (blood glucose and lactate concentrations and pH). Physiological stress values showed a negative trend with fight duration and total fight intensity, but a positive trend with average fight intensity. Water temperature emerged as the most important predictor of the stress response in largemouth bass, while fight duration and intensity were not strong predictors. Reflex impairment was minimal, but higher reflex impairment scores were associated with elevated blood glucose. Overall, the findings of this study suggest that angling for largemouth bass at colder temperatures (<15°C) causes greater physiological stress than at warmer temperatures (>20°C). Based on our findings, we conclude that fight intensity is likely not to be a major driver of physiological stress in this species using typical largemouth bass angling gear, owing to the relatively short fight times (i.e. <2 min). PMID:27293678
Prevalence and associated factors of physical fighting among school-going adolescents in Namibia.
Rudatsikira, Emmanuel; Siziya, Seter; Kazembe, Lawrence N; Muula, Adamson S
2007-07-24
Interpersonal physical violence is an important global public health concern that has received limited attention in the developing world. There is in particular a paucity of data regarding physical violence and its socio-demographic correlates among in-school adolescents in Namibia. We analysed cross-sectional data from the Namibia Global School-Based Health Survey (GSHS) conducted in 2004. We aimed to estimate the prevalence and socio-demographic correlates of physical fighting within the last 12 months. We obtained frequencies of socio-demographic attributes. We also assessed the association between self-reported history of having engaging in a physical fight and a selected list of independent variables using logistic regression analysis. Of the 6283 respondents, 50.6% (55.2% males and 46.2% females) reported having been in a physical fight in the past 12 months. Males were more likely to have been in a physical fight than females (OR = 1.71, 95% CI (1.44, 2.05)). Smoking, drinking alcohol, using drugs and bullying victimization were positively associated with fighting (OR = 1.91, 95% CI (1.49, 2.45); OR = 1.48, 95% CI (1.21, 1.81); OR = 1.55, 95% CI (1.22, 1.81); and OR = 3.12, 95% CI (2.62, 3.72), respectively). Parental supervision was negatively associated with physical fighting (OR = 0.82, 95% CI (0.69, 0.98)). Both male and female substance users (cigarette smoking, alcohol and drug use) were more likely to engage in physical fighting than non-substance users (OR = 3.53, 95% CI (2.60, 4.81) for males and OR = 11.01, 95% CI (7.25, 16.73) for females). Parental supervision was negatively associated with physical fighting (OR = 0.85, 95% CI (0.72, 0.99)). Prevalence of physical fighting within the last 12 months was comparable to estimates obtained in European countries. We also found clustering of problem behaviours or experiences among adolescents who reported having engaged in physical violence in the past 12 months. There is a need to bring adolescent violent behaviour to the fore of the public health agenda in Namibia.
[Restoration of the idea of contact. Psychopedagogic approach].
Richaud, R L
1988-01-01
Our psychopedagogical work with teenagers having serious problems in the school setting led us to set up a clinical approach giving back to thought the ability to link affects and their representations whereas the thought process had seemed exhausted by a never-ending fight to avoid being swallowed up by the primary processes or through representing unbearable phantasms. In our hypothesis, as long as the imaginary can't be represented, it blocks access to any idea of contact. Having contact with works of art, which can serve as models of metamorphosis that has succeeded, seemed, to us, in the concept of a shared dream, as the best way to allows patients to reconnect lost or avoided parts, but from afar. The metaphor takes the place of the nameless crudity and horror of a very real alienating agent.
Forecasting techno-social systems: how physics and computing help to fight off global pandemics
NASA Astrophysics Data System (ADS)
Vespignani, Alessandro
2010-03-01
The crucial issue when planning for adequate public health interventions to mitigate the spread and impact of epidemics is risk evaluation and forecast. This amount to the anticipation of where, when and how strong the epidemic will strike. In the last decade advances in performance in computer technology, data acquisition, statistical physics and complex networks theory allow the generation of sophisticated simulations on supercomputer infrastructures to anticipate the spreading pattern of a pandemic. For the first time we are in the position of generating real time forecast of epidemic spreading. I will review the history of the current H1N1 pandemic, the major road-blocks the community has faced in its containment and mitigation and how physics and computing provide predictive tools that help us to battle epidemics.
Fuxjager, Matthew J; Forbes-Lorman, Robin M; Coss, Dylan J; Auger, Catherine J; Auger, Anthony P; Marler, Catherine A
2010-07-06
Winning aggressive disputes can enhance future fighting ability and the desire to seek out additional contests. In some instances, these effects are long lasting and vary in response to the physical location of a fight. Thus, in principle, winning aggressive encounters may cause long-term and context-dependent changes to brain areas that control the output of antagonistic behavior or the motivation to fight (or both). We examined this issue in the territorial California mouse (Peromyscus californicus) because males of this species are more likely to win fights after accruing victories in their home territory but not after accruing victories in unfamiliar locations. Using immunocytochemistry and real-time quantitative PCR, we found that winning fights either at home or away increases the expression of androgen receptors (AR) in the medial anterior bed nucleus of the stria terminalis, a key brain area that controls social aggression. We also found that AR expression in brain regions that mediate motivation and reward, nucleus accumbens (NAcc) and ventral tegmental area (VTA), increases only in response to fights in the home territory. These effects of winning were likely exclusive to the neural androgenic system because they have no detectible impact on the expression of progestin receptors. Finally, we demonstrated that the observed changes in androgen sensitivity in the NAcc and VTA are positively associated with the ability to win aggressive contests. Thus, winning fights can change brain phenotype in a manner that likely promotes future victory and possibly primes neural circuits that motivate individuals to fight.
The effects of multiple obstacles on the locomotor behavior and performance of a terrestrial lizard.
Parker, Seth E; McBrayer, Lance D
2016-04-01
Negotiation of variable terrain is important for many small terrestrial vertebrates. Variation in the running surface resulting from obstacles (woody debris, vegetation, rocks) can alter escape paths and running performance. The ability to navigate obstacles likely influences survivorship through predator evasion success and other key ecological tasks (finding mates, acquiring food). Earlier work established that running posture and sprint performance are altered when organisms face an obstacle, and yet studies involving multiple obstacles are limited. Indeed, some habitats are cluttered with obstacles, whereas others are not. For many species, obstacle density may be important in predator escape and/or colonization potential by conspecifics. This study examines how multiple obstacles influence running behavior and locomotor posture in lizards. We predict that an increasing number of obstacles will increase the frequency of pausing and decrease sprint velocity. Furthermore, bipedal running over multiple obstacles is predicted to maintain greater mean sprint velocity compared with quadrupedal running, thereby revealing a potential advantage of bipedalism. Lizards were filmed running through a racetrack with zero, one or two obstacles. Bipedal running posture over one obstacle was significantly faster than quadrupedal posture. Bipedal running trials contained fewer total strides than quadrupedal ones. But on addition of a second obstacle, the number of bipedal strides decreased. Increasing obstacle number led to slower and more intermittent locomotion. Bipedalism provided clear advantages for one obstacle, but was not associated with further benefits for an additional obstacle. Hence, bipedalism helps mitigate obstacle negotiation, but not when numerous obstacles are encountered in succession. © 2016. Published by The Company of Biologists Ltd.
46 CFR 185.524 - Fire fighting drills and training.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 7 2010-10-01 2010-10-01 false Fire fighting drills and training. 185.524 Section 185... 100 GROSS TONS) OPERATIONS Preparations for Emergencies § 185.524 Fire fighting drills and training. (a) The master shall conduct sufficient fire drills to make sure that each crew member is familiar...
Individual, Family, and Peer predictors of Violence among Samoan Adolescents
ERIC Educational Resources Information Center
Stevens, Devan L.; Hardy, Sam A.
2013-01-01
This study explored individual, family, and peer predictors of involvement and psychological investment in fights among Samoan youth. Participants were 310 adolescents ages 13 through 19 living in Samoa. MANCOVAs compared those involved in fights with those not, and those more investing in fighting with those less invested. In terms of individual…
School and Family Counselors Work Together to Reduce Fighting at School
ERIC Educational Resources Information Center
Canfield, Brian S.; Ballard, Mary B.; Osmon, Bonnie C.; McCune, Cecil
2004-01-01
To address the problem of fighting in four urban middle schools, school and family counselors collaborated to provide school-based multifamily counseling as an alternative to the mandatory 3-day external suspension program. Supported by district leaders and local school principals, the program was successful in reducing fighting recidivism rates.…
46 CFR 185.524 - Fire fighting drills and training.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 7 2011-10-01 2011-10-01 false Fire fighting drills and training. 185.524 Section 185... 100 GROSS TONS) OPERATIONS Preparations for Emergencies § 185.524 Fire fighting drills and training. (a) The master shall conduct sufficient fire drills to make sure that each crew member is familiar...
46 CFR 185.524 - Fire fighting drills and training.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 7 2014-10-01 2014-10-01 false Fire fighting drills and training. 185.524 Section 185... 100 GROSS TONS) OPERATIONS Preparations for Emergencies § 185.524 Fire fighting drills and training. (a) The master shall conduct sufficient fire drills to make sure that each crew member is familiar...
46 CFR 185.524 - Fire fighting drills and training.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 7 2012-10-01 2012-10-01 false Fire fighting drills and training. 185.524 Section 185... 100 GROSS TONS) OPERATIONS Preparations for Emergencies § 185.524 Fire fighting drills and training. (a) The master shall conduct sufficient fire drills to make sure that each crew member is familiar...
46 CFR 185.524 - Fire fighting drills and training.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 7 2013-10-01 2013-10-01 false Fire fighting drills and training. 185.524 Section 185... 100 GROSS TONS) OPERATIONS Preparations for Emergencies § 185.524 Fire fighting drills and training. (a) The master shall conduct sufficient fire drills to make sure that each crew member is familiar...
A Fight Worth Fighting, a Fight Worth Winning
ERIC Educational Resources Information Center
Carpenter, Wade A.
2010-01-01
Losing one's mother naturally makes a person reflect on the really important things. The author was reminded that when faced with the Great Question, which even the best schools cannot handle competently, all other questions can seem trivial, and it's tempting to back away from them. But the "lesser" questions schools mishandle can have…
ERIC Educational Resources Information Center
Giroux, Henry A.
2001-01-01
Analyzes the narrative structure of the film "Fight Club," addressing its critique of consumerism and its celebration of masculinity. Addresses the representational politics that structure the movie, especially its deeply conventional views of violence, gender relations, and masculinity. Considers the role that "Fight Club" and other cultural…
Plowes, Nicola J.R; Adams, Eldridge S
2005-01-01
Lanchester's models of attrition describe casualty rates during battles between groups as functions of the numbers of individuals and their fighting abilities. Originally developed to describe human warfare, Lanchester's square law has been hypothesized to apply broadly to social animals as well, with important consequences for their aggressive behaviour and social structure. According to the square law, the fighting ability of a group is proportional to the square of the number of individuals, but rises only linearly with fighting ability of individuals within the group. By analyzing mortality rates of fire ants (Solenopsis invicta) fighting in different numerical ratios, we provide the first quantitative test of Lanchester's model for a non-human animal. Casualty rates of fire ants were not consistent with the square law; instead, group fighting ability was an approximately linear function of group size. This implies that the relative numbers of casualties incurred by two fighting groups are not strongly affected by relative group sizes and that battles do not disproportionately favour group size over individual prowess. PMID:16096093
Block QCA Fault-Tolerant Logic Gates
NASA Technical Reports Server (NTRS)
Firjany, Amir; Toomarian, Nikzad; Modarres, Katayoon
2003-01-01
Suitably patterned arrays (blocks) of quantum-dot cellular automata (QCA) have been proposed as fault-tolerant universal logic gates. These block QCA gates could be used to realize the potential of QCA for further miniaturization, reduction of power consumption, increase in switching speed, and increased degree of integration of very-large-scale integrated (VLSI) electronic circuits. The limitations of conventional VLSI circuitry, the basic principle of operation of QCA, and the potential advantages of QCA-based VLSI circuitry were described in several NASA Tech Briefs articles, namely Implementing Permutation Matrices by Use of Quantum Dots (NPO-20801), Vol. 25, No. 10 (October 2001), page 42; Compact Interconnection Networks Based on Quantum Dots (NPO-20855) Vol. 27, No. 1 (January 2003), page 32; Bit-Serial Adder Based on Quantum Dots (NPO-20869), Vol. 27, No. 1 (January 2003), page 35; and Hybrid VLSI/QCA Architecture for Computing FFTs (NPO-20923), which follows this article. To recapitulate the principle of operation (greatly oversimplified because of the limitation on space available for this article): A quantum-dot cellular automata contains four quantum dots positioned at or between the corners of a square cell. The cell contains two extra mobile electrons that can tunnel (in the quantummechanical sense) between neighboring dots within the cell. The Coulomb repulsion between the two electrons tends to make them occupy antipodal dots in the cell. For an isolated cell, there are two energetically equivalent arrangements (denoted polarization states) of the extra electrons. The cell polarization is used to encode binary information. Because the polarization of a nonisolated cell depends on Coulomb-repulsion interactions with neighboring cells, universal logic gates and binary wires could be constructed, in principle, by arraying QCA of suitable design in suitable patterns. Heretofore, researchers have recognized two major obstacles to realization of QCA-based logic gates: One is the need for (and the difficulty of attaining) operation of QCA circuitry at room temperature or, for that matter, at any temperature above a few Kelvins. It has been theorized that room-temperature operation could be made possible by constructing QCA as molecular-scale devices. However, in approaching the lower limit of miniaturization at the molecular level, it becomes increasingly imperative to overcome the second major obstacle, which is the need for (and the difficulty of attaining) high precision in the alignments of adjacent QCA in order to ensure the correct interactions among the quantum dots.
Aravind, Gayatri; Darekar, Anuja; Fung, Joyce; Lamontagne, Anouk
2015-03-01
Persons with post-stroke visuospatial neglect (VSN) often collide with moving obstacles while walking. It is not well understood whether the collisions occur as a result of attentional-perceptual deficits caused by VSN or due to post-stroke locomotor deficits. We assessed individuals with VSN on a seated, joystick-driven obstacle avoidance task, thus eliminating the influence of locomotion. Twelve participants with VSN were tested on obstacle detection and obstacle avoidance tasks in a virtual environment that included three obstacles approaching head-on or 30 (°) contralesionally/ipsilesionally. Our results indicate that in the detection task, the contralesional and head-on obstacles were detected at closer proximities compared to the ipsilesional obstacle. For the avoidance task collisions were observed only for the contralesional and head-on obstacle approaches. For the contralesional obstacle approach, participants initiated their avoidance strategies at smaller distances from the obstacle and maintained smaller minimum distances from the obstacles. The distance at detection showed a negative association with the distance at the onset of avoidance strategy for all three obstacle approaches. We conclusion the observation of collisions with contralesional and head-on obstacles, in the absence of locomotor burden, provides evidence that attentional-perceptual deficits due to VSN, independent of post-stroke locomotor deficits, alter obstacle avoidance abilities.
Faurie, Charlotte; Raymond, Michel
2013-06-01
The ubiquitous and persistent handedness polymorphism in humans requires an evolutionary explanation. It has been suggested that left-handers have a frequency-dependent advantage during a fight, such that this advantage decreases when their frequency increases. Many independent studies are providing data from interactive sports (a specific class of fights), and are very supportive of the fighting hypothesis. The only intercultural study on traditional societies is also consistent with the fighting hypothesis, although it has not yet been replicated. The frequencies of left-handers in the few remaining violent societies are likely to be rapidly decreasing, due to Western colonization (long-range weapons, religion, and money market) dramatically affecting the frequency-dependent selection associated with handedness. Clearly, more data are urgently needed outside the Western influence. © 2013 New York Academy of Sciences.
Fighting like a girl fighting like a guy: gender identity, ideology, and girls at early adolescence.
Brown, Lyn Mikel; Tappan, Mark B
2008-01-01
In this chapter we explore the phenomenon of "girls fighting like guys" by listening to adolescent girls' justification for physical fighting with other girls. We argue that physical girlfighting is a particular kind of gendered performance--a performance of identity that expresses, at least in part, an answer to the question, "Who am I?"--that both perpetuates and challenges the usual notions of masculinity and femininity and the differential power associated with these discourses. We present a sociocultural approach to identity that we believe not only holds promise for helping us to understand girl-fighting behavior but also highlights the clear interrelationship between social identity and personal identity. We conclude by highlighting several implications of this analysis for those who work with girls (and boys) in educational and clinical settings.
Robert, Jean-Luc; Erkamp, Ramon; Korukonda, Sanghamithra; Vignon, François; Radulescu, Emil
2015-11-01
In ultrasound imaging, an array of elements is used to image a medium. If part of the array is blocked by an obstacle, or if the array is made from several sub-arrays separated by a gap, grating lobes appear and the image is degraded. The grating lobes are caused by missing spatial frequencies, corresponding to the blocked or non-existing elements. However, in an active imaging system, where elements are used both for transmitting and receiving, the round trip signal is redundant: different pairs of transmit and receive elements carry similar information. It is shown here that, if the gaps are smaller than the active sub-apertures, this redundancy can be used to compensate for the missing signals and recover full resolution. Three algorithms are proposed: one is based on a synthetic aperture method, a second one uses dual-apodization beamforming, and the third one is a radio frequency (RF) data based deconvolution. The algorithms are evaluated on simulated and experimental data sets. An application could be imaging through ribs with a large aperture.
Wolkers, C P B; Serra, M; Szawka, R E; Urbinati, E C
2014-01-01
This study evaluated the influence of dietary L-tryptophan (TRP) supplementation on the time course of aggressive behaviour and on neuroendocrine and hormonal indicators in juvenile matrinxã Brycon amazonicus. Supplementation with TRP promoted a change in the fight pattern at the beginning of an interaction with an intruder, resulting in decreased aggressive behaviours during the first 20 min. The decrease in aggression did not persist throughout the interaction but increased at 3 and 6 h after the beginning of the fight. Monoamine levels in the hypothalamus were not influenced by TRP before or after the fight; however, the hypothalamic serotonin (5-HT) concentration and the 5-hydroxyindole-3-acetic acid (5HIAA):5-HT ratio were significantly correlated with the reduction in aggressive behaviour at the beginning of the fight. Cortisol was not altered by TRP before the fight. After the fight cortisol increased to higher levels in B. amazonicus fed with supplementary TRP. These results indicate that TRP supplementation alters the aggressive behaviour of B. amazonicus and that this effect is limited to the beginning of the fight, suggesting a transient effect of TRP on aggressive behaviour. This is the first study reporting the effects of TRP supplementation on the time course of aggressive interaction in fishes. © 2013 The Fisheries Society of the British Isles.
Lee, Yun-Ju; Hoozemans, Marco J M; van Dieën, Jaap H
2012-01-01
Unexpected sudden (un)loading of the trunk may induce inadequate responses of trunk muscles and uncontrolled trunk motion. These unexpected perturbations may occur in pushing tasks, when the cart suddenly starts moving (unloading) or is blocked by an obstacle (loading). In pushing, handle height affects the user's working posture, which may influence trunk muscle activity and trunk movement in response to the perturbation. Eleven healthy male subjects pushed a 200 kg cart with handles at shoulder and hip height in a start condition (sudden release of brakes) and a stop condition (bumping into an obstacle). Before the perturbation, the baseline of the trunk inclination, internal moment and trunk extensor muscle activity were significantly higher when pushing at hip height than at shoulder height. After the perturbation, the changes in trunk inclination and internal moment were significantly larger when pushing at shoulder height than at hip height in both conditions. The opposite directions of changes in trunk inclination and internal moment suggest that the unexpected perturbations caused uncontrolled trunk motion. Pushing at shoulder height may impose a high risk of low-back injury due to the low trunk stiffness and large involuntary trunk motion occurring after carts suddenly move or stop.
Transitioning from a single-phase fluid to a porous medium: a boundary layer approach
NASA Astrophysics Data System (ADS)
Dalwadi, Mohit P.; Chapman, S. Jon; Oliver, James M.; Waters, Sarah L.
2014-11-01
Pressure-driven laminar channel flow is a classic problem in fluid mechanics, and the resultant Poiseuille flow is one of the few exact solutions to the Navier-Stokes equations. If the channel interior is a porous medium (governed by Darcy's law) rather than a single-phase fluid, the resultant behaviour is plug flow. But what happens when these two flow regions are coupled, as is the case for industrial membrane filtration systems or biological tissue engineering problems? How does one flow transition to the other? We use asymptotic methods to investigate pressure-driven flow through a long channel completely blocked by a finite-length porous obstacle. We analytically solve for the flow at both small and large Reynolds number (whilst remaining within the laminar regime). The boundary layer structure is surprisingly intricate for large Reynolds number. In that limit, the structure is markedly different depending on whether there is inflow or outflow through the porous medium, there being six asymptotic regions for inflow and three for outflow. We have extended this result to a wide class of 3D porous obstacles within a Hele-Shaw cell. We obtain general boundary conditions to couple the outer flows, and find that these conditions are far from obvious at higher order.
46 CFR 122.524 - Fire fighting drills and training.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Fire fighting drills and training. 122.524 Section 122... Preparations for Emergencies § 122.524 Fire fighting drills and training. (a) The master shall conduct sufficient fire drills to make sure that each crew member is familiar with his or her duties in case of a...
The Positive Aspects of Aggressive Behavior in Young Children.
ERIC Educational Resources Information Center
Periolat, Janet; Nager, Nancy
Not all fighting or aggression in young children is bad, and some kinds of teacher intervention may be beneficial. Play-fighting refers primarily to rough and tumble play and chasing, and several studies have shown that play and serious fighting can be clearly distinguished in young children. Numerous authors have pointed out the value and…
ERIC Educational Resources Information Center
Hayashi, Leslie Ann
2008-01-01
This article presents a story from Hawaii about how it is better to share and cooperate than to squabble and fight. The story is about two large mynah birds fighting for a ripe mango hanging from a tree. In the midst of their battle, a mother and father sparrow pecked small pieces from the mango to feed their large hungry family. Flying back and…
"Girls Are Worse": Drama Queens, Ghetto Girls, Tomboys, and the Meaning of Girl Fights
ERIC Educational Resources Information Center
Waldron, Linda M.
2011-01-01
This article uses a race-class-gender intersectional approach to analyze qualitative interviews with girls at two public high schools to better understand a common perception that "girls are worse" when it comes to school fights. Several different understandings of why girls fight emerged from the data. On one hand, girls' perception of…
46 CFR 122.524 - Fire fighting drills and training.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 4 2012-10-01 2012-10-01 false Fire fighting drills and training. 122.524 Section 122... Preparations for Emergencies § 122.524 Fire fighting drills and training. (a) The master shall conduct sufficient fire drills to make sure that each crew member is familiar with his or her duties in case of a...
46 CFR 122.524 - Fire fighting drills and training.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 4 2013-10-01 2013-10-01 false Fire fighting drills and training. 122.524 Section 122... Preparations for Emergencies § 122.524 Fire fighting drills and training. (a) The master shall conduct sufficient fire drills to make sure that each crew member is familiar with his or her duties in case of a...
46 CFR 122.524 - Fire fighting drills and training.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 4 2011-10-01 2011-10-01 false Fire fighting drills and training. 122.524 Section 122... Preparations for Emergencies § 122.524 Fire fighting drills and training. (a) The master shall conduct sufficient fire drills to make sure that each crew member is familiar with his or her duties in case of a...
46 CFR 122.524 - Fire fighting drills and training.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 4 2014-10-01 2014-10-01 false Fire fighting drills and training. 122.524 Section 122... Preparations for Emergencies § 122.524 Fire fighting drills and training. (a) The master shall conduct sufficient fire drills to make sure that each crew member is familiar with his or her duties in case of a...
Prefrontal cortex activation during obstacle negotiation: What's the effect size and timing?
Maidan, Inbal; Shustak, Shiran; Sharon, Topaz; Bernad-Elazari, Hagar; Geffen, Nimrod; Giladi, Nir; Hausdorff, Jeffrey M; Mirelman, Anat
2018-04-01
Obstacle negotiation is a daily activity that requires the integration of sensorimotor and cognitive information. Recent studies provide evidence for the important role of prefrontal cortex during obstacle negotiation. We aimed to explore the effects of obstacle height and available response time on prefrontal activation. Twenty healthy young adults (age: 30.1 ± 1.0 years; 50% women) walked in an obstacle course while negotiating anticipated and unanticipated obstacles at heights of 50 mm and 100 mm. Prefrontal activation was measured using a functional near-infrared spectroscopy system. Kinect cameras measured the obstacle negotiation strategy. Prefrontal activation was defined based on mean level of HbO 2 before, during and after obstacle negotiation and the HbO 2 slope from gait initiation and throughout the task. Changes between types of obstacles were assessed using linear-mix models and partial correlation analyses evaluated the relationship between prefrontal activation and the distance between the feet as the subjects traversed the obstacles. Different obstacle heights showed similar changes in prefrontal activation measures (p > 0.210). However, during unanticipated obstacles, the slope of the HbO 2 response was steeper (p = 0.048), as compared to anticipated obstacles. These changes in prefrontal activation during negotiation of unanticipated obstacles were correlated with greater distance of the leading foot after the obstacles (r = 0.831, p = 0.041). These findings are the first to show that the pattern of prefrontal activation depends on the nature of the obstacle. More specifically, during unanticipated obstacles the recruitment of the prefrontal cortex is faster and greater than during negotiating anticipated obstacles. These results provide evidence of the important role of the prefrontal cortex and the ability of healthy young adults to tailor the activation pattern to different types of obstacles. Copyright © 2018 Elsevier Inc. All rights reserved.
Brand preferences of underage drinkers who report alcohol-related fights and injuries
Roberts, Sarah P.; Siegel, Michael B.; DeJong, William; Naimi, Timothy S.; Jernigan, David H.
2014-01-01
Background A significant body of research has demonstrated an association between adolescent alcohol consumption and subsequent fights and injuries. To date, however, no research has identified which brands are associated with alcohol-related fights and injuries among underage drinkers. Objectives We aimed to: 1) report the prevalence of alcohol-related fights and injuries among a national sample of underage drinkers in the U.S. and 2) describe the relationship between specific alcohol brand consumption and these alcohol-related negative consequences. Methods We recruited 1,031 self-reported drinkers (ages 13–20 years) via an internet panel maintained by Knowledge Networks to complete an online survey. Respondents reported their past-month overall and brand-specific alcohol consumption, risky drinking behavior, and past-year alcohol-related fights and injuries. Results Over one-quarter of the respondents (26.7%, N=232) reported at least one alcohol-related fight or injury in the past year. Heavy episodic drinkers were over six times more likely to report one of these negative alcohol-related consequences (AOR: 6.4, 95% CI: 4.1–9.9). Respondents of black race and those from higher-income households were also significantly more likely to report that experience (AOR: 2.2, 95% CI: 1.3–3.7; AOR: 1.8, 95% CI: 1.1–3.0 and 1.1–3.2, respectively). We identified eight alcohol brands that were significantly associated with alcohol-related fights and injuries. Conclusions/Importance Alcohol-related fights and injuries were frequently reported by adolescent respondents. Eight alcohol brands were significantly more popular among drinkers who experienced these adverse consequences. These results point to the need for further research on brand-specific correlates of underage drinking and negative health outcomes. PMID:25612075
Play fighting and corticotropin-releasing hormone in the lateral septum of golden hamsters.
Cheng, S Y; Delville, Y
2010-08-11
This study was focused on determining the possible role of corticotropin-releasing hormone (CRH) on play fighting in juvenile golden hamsters. As no specific neural sites have been proposed, we looked for changes in CRH innervations at the peak of play-fighting activity on postnatal day 35 (P-35) from a week before on P-28. We noted that the increase in play-fighting activity between these two dates was associated with a 100% increase of the density of CRH fibers within the lateral septum. We, then, tested the possible role of CRH receptors on play fighting within the lateral septum through microinjections of alpha-helical CRH, a CRH receptor antagonist (either 0, 30, or 300 ng), directly into the area. The treatments inhibited play-fighting attacks and pins as well as reduced the duration of time that the resident hamsters spent in contact with the intruders, though locomotor activity remained unaffected. The possible source of CRH release in the lateral septum was addressed by quantification of CRH neurons also labeled with a marker of cellular activity, c-Fos, after consummation of play fighting. CRH neurons in the horizontal part of the diagonal band, an area reciprocally connected with the lateral septum, showed a 75% increase in double labeling with c-Fos as compared to controls. Together, these data show that CRH receptors in the lateral septum have a general role on play fighting, not just facilitating its consummation, but also likely enhancing appetitive aspects as well. In addition, this effect is associated with enhanced CRH availability in the area and enhanced neuronal activity within interconnected areas. Copyright (c) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.
Brand preferences of underage drinkers who report alcohol-related fights and injuries.
Roberts, Sarah P; Siegel, Michael B; DeJong, William; Naimi, Timothy S; Jernigan, David H
2015-04-01
A significant body of research has demonstrated an association between adolescent alcohol consumption and subsequent fights and injuries. To date, however, no research has identified which brands are associated with alcohol-related fights and injuries among underage drinkers. We aimed to: (1) report the prevalence of alcohol-related fights and injuries among a national sample of underage drinkers in the U.S. and (2) describe the relationship between specific alcohol brand consumption and these alcohol-related negative consequences. We recruited 1,031 self-reported drinkers (ages 13-20 years) via an internet panel maintained by Knowledge Networks to complete an online survey. Respondents reported their past-month overall and brand-specific alcohol consumption, risky drinking behavior, and past-year alcohol-related fights and injuries. Over one-quarter of the respondents (26.7%, N = 232) reported at least one alcohol-related fight or injury in the past year. Heavy episodic drinkers were over six times more likely to report one of these negative alcohol-related consequences (AOR: 6.4, 95% CI: 4.1-9.9). Respondents of black race and those from higher-income households were also significantly more likely to report that experience (AOR: 2.2, 95% CI: 1.3-3.7; AOR: 1.8, 95% CI: 1.1-3.0 and 1.1-3.2, respectively). We identified eight alcohol brands that were significantly associated with alcohol-related fights and injuries. CONCLUSIONS/IMPORTANCE: Alcohol-related fights and injuries were frequently reported by adolescent respondents. Eight alcohol brands were significantly more popular among drinkers who experienced these adverse consequences. These results point to the need for further research on brand-specific correlates of underage drinking and negative health outcomes.
Age-associated changes in obstacle negotiation strategies: Does size and timing matter?
Maidan, I; Eyal, S; Kurz, I; Geffen, N; Gazit, E; Ravid, L; Giladi, N; Mirelman, A; Hausdorff, J M
2018-01-01
Tripping over an obstacle is one of the most common causes of falls among older adults. However, the effects of aging, obstacle height and anticipation time on negotiation strategies have not been systematically evaluated. Twenty older adults (ages: 77.7±3.4years; 50% women) and twenty young adults (age: 29.3±3.8years; 50% women) walked through an obstacle course while negotiating anticipated and unanticipated obstacles at heights of 25mm and 75mm. Kinect cameras captured the: (1) distance of the subject's trailing foot before the obstacles, (2) distance of the leading foot after the obstacles, (3) clearance of the leading foot above the obstacles, and (4) clearance of the trailing foot above the obstacles. Linear-mix models assessed changes between groups and conditions. Older adults placed their leading foot closer to the obstacle after landing, compared to young adults (p<0.001). This pattern was enhanced in high obstacles (group*height interaction, p=0.033). Older adults had lower clearance over the obstacles, compared to young adults (p=0.007). This was more pronounced during unanticipated obstacles (group*ART interaction, p=0.003). The distance of the leading foot and clearance of the trailing foot after the obstacles were correlated with motor, cognitive, and functional abilities. These findings suggest that there are age-related changes in obstacle crossing strategies that are dependent on the specific characteristics of the obstacle. The results have important implications for clinical practice, suggesting that functional exercise should include obstacle negotiation training with variable practice of height and available response times. Further studies are needed to better understand the effects of motor and cognitive abilities. Copyright © 2017 Elsevier B.V. All rights reserved.
Robust obstacle detection for unmanned surface vehicles
NASA Astrophysics Data System (ADS)
Qin, Yueming; Zhang, Xiuzhi
2018-03-01
Obstacle detection is of essential importance for Unmanned Surface Vehicles (USV). Although some obstacles (e.g., ships, islands) can be detected by Radar, there are many other obstacles (e.g., floating pieces of woods, swimmers) which are difficult to be detected via Radar because these obstacles have low radar cross section. Therefore, detecting obstacle from images taken onboard is an effective supplement. In this paper, a robust vision-based obstacle detection method for USVs is developed. The proposed method employs the monocular image sequence captured by the camera on the USVs and detects obstacles on the sea surface from the image sequence. The experiment results show that the proposed scheme is efficient to fulfill the obstacle detection task.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yu, Yanlan; Chen, Yicheng; Ding, Guoqing
The hepatocyte growth factor and its receptor c-Met are correlated with castration-resistance in prostate cancer. Although HGF has been considered as an attractive target for therapeutic antibodies, the lack of cross-reactivity of monoclonal antibodies with human/mouse HGFs is a major obstacle in preclinical developments. We generated a panel of anti-HGF RabMAbs either blocking HGF/c-Met interaction or inhibiting c-Met phosphorylation. We selected one RabMAb with mouse cross-reactivity and demonstrated that it blocked HGF-stimulated downstream activation in PC-3 and DU145 cells. Anti-HGF RabMAb inhibited not only the growth of PC-3 cells but also HGF-dependent proliferation in HUVECs. We further demonstrated the efficacymore » and potency of the anti-HGF RabMAb in tumor xenograft mice models. Through these in vitro and in vivo experiments, we explored a novel therapeutic antibody for advanced prostate cancer. - Highlights: • HGF is an attractive target for castration-refractory prostate cancer. • We generated and characterized a panel of anti-HGF rabbit monoclonal antibodies. • More than half of these anti-HGF RabMAbs was cross-reactive with mouse HGF. • Anti-HGF RabMAb blocks HGF-stimulated phosphorylation and cell growth in vitro. • Anti-HGF RabMAb inhibits tumor growth and angiogenesis in xenograft mice.« less
Fast obstacle detection based on multi-sensor information fusion
NASA Astrophysics Data System (ADS)
Lu, Linli; Ying, Jie
2014-11-01
Obstacle detection is one of the key problems in areas such as driving assistance and mobile robot navigation, which cannot meet the actual demand by using a single sensor. A method is proposed to realize the real-time access to the information of the obstacle in front of the robot and calculating the real size of the obstacle area according to the mechanism of the triangle similarity in process of imaging by fusing datum from a camera and an ultrasonic sensor, which supports the local path planning decision. In the part of image analyzing, the obstacle detection region is limited according to complementary principle. We chose ultrasonic detection range as the region for obstacle detection when the obstacle is relatively near the robot, and the travelling road area in front of the robot is the region for a relatively-long-distance detection. The obstacle detection algorithm is adapted from a powerful background subtraction algorithm ViBe: Visual Background Extractor. We extracted an obstacle free region in front of the robot in the initial frame, this region provided a reference sample set of gray scale value for obstacle detection. Experiments of detecting different obstacles at different distances respectively, give the accuracy of the obstacle detection and the error percentage between the calculated size and the actual size of the detected obstacle. Experimental results show that the detection scheme can effectively detect obstacles in front of the robot and provide size of the obstacle with relatively high dimensional accuracy.
Genomics and epigenetics of sexual commitment in Plasmodium.
Bechtsi, D P; Waters, A P
2017-06-01
Malaria is the disease caused by the apicomplexan parasites belonging to the genus Plasmodium. Expanding our arsenal to include transmission-blocking agents in our fight against malaria is becoming increasingly important. Such an implementation requires detailed understanding of the biology of the Plasmodium life cycle stages that are transmissible. Plasmodium gametocytes are the only parasite stage that can be transmitted to the mosquito vector and are the product of sexual development in a small percentage of parasites that continually proliferate in host blood. The critical decision made by asexual erythrocytic stages to cease further proliferation and differentiate into gametocytes, as well as the first steps they take into maturity, have long remained unknown. Recent studies have contributed to a breakthrough in our understanding of this branch point in development. In this review, we will discuss the findings that have allowed us to make this major leap forward in our knowledge of sexual commitment in Plasmodium. We will further propose a model for the mechanism triggering the switch to sexual development, constructed around the proteins currently known to regulate this process. Further insight into sexual commitment and gametocyte development will help identify targets for the development of transmission-blocking malaria therapies. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.
ERIC Educational Resources Information Center
Roberto, Anthony J.; Meyer, Gary; Boster, Franklin J.; Roberto, Heather L.
2003-01-01
Examines the ability of the theory of reasoned action to explain and predict adolescents' verbal (i.e., insulting) and physical (i.e., fighting) aggression, as well as behaviors that encourage aggression such as watching a fight or telling others about a fight that is going to happen. Reveals that attitudes and subjective norms predicted…
ERIC Educational Resources Information Center
Hong, Jun Sung; Merrin, Gabriel J.; Peguero, Anthony A.; Gonzalez-Prendes, A. Antonio; Lee, Na Youn
2016-01-01
Background: Despite the growing presence of immigrant families in the US, little is known about physical fighting in school among youth from those families. Objective: The present study examines the social-ecological determinants of school physical fighting among youth in immigrant families. Implications for practice are also discussed. Method:…
Teaching for Social Justice--Teaching Our Children: A Discussion with Susan Ohanian
ERIC Educational Resources Information Center
Hunt, Jean Ann; Hutchinson, Jaylynne N.
2008-01-01
This article presents an interview with Susan Ohanian, an educator and tireless advocate of educational social justice for young people, and a peerless guide to engaging in the "good fight" for creating socially just schools. When asked how a teacher can "fight the good fight" without giving up, Susan counseled educators to find a friend and ally,…
ERIC Educational Resources Information Center
Carlson, Frances
2009-01-01
Many people fear that play-fighting or rough and tumble play is the same as real fighting. There is also a fear that this rough play will become real fighting if allowed to continue. Most of all, parents and teachers fear that during the course of rough and tumble play a child may be hurt. To provide for and allow children to play rough without…
Boulton, Michael J
2012-09-01
Hostile attribution bias (HAB) has been found to characterize aggressive children. Watching prosocial media has been shown to have positive effects on children, and the general learning model has been used to account for these observations. This study tested the hypotheses derived from this theory that exposure to playful fighting would lead to a reduction in HAB, both immediately and after a 1-day delay, and that this effect would be mediated by positive thoughts. Four studies exposed child participants (N=242) to playful fighting versus neutral behavior primes and then tested their HAB. In two studies, thoughts about playful fighting and about children were assessed and tested as mediators. The main hypotheses were supported. The positive effect of watching playful fighting on HAB was evident immediately but not after 1 day. This effect was mediated by positive thoughts. In line with the general learning model, watching playful fighting reduced HAB in children, and positive thoughts contribute to this effect. This extends the realm of the general learning model and suggests interventions to help children avoid aggression. Copyright © 2012. Published by Elsevier Inc.
Veenendaal, Andreas K. J.; Sundin, Charlotta; Blocker, Ariel J.
2009-01-01
Type III secretion systems (T3SSs) are essential virulence devices for many gram-negative bacteria that are pathogenic for plants, animals, and humans. They serve to translocate virulence effector proteins directly into eukaryotic host cells. T3SSs are composed of a large cytoplasmic bulb and a transmembrane region into which a needle is embedded, protruding above the bacterial surface. The emerging antibiotic resistance of bacterial pathogens urges the development of novel strategies to fight bacterial infections. Therapeutics that rather than kill bacteria only attenuate their virulence may reduce the frequency or progress of resistance emergence. Recently, a group of salicylidene acylhydrazides were identified as inhibitors of T3SSs in Yersinia, Chlamydia, and Salmonella species. Here we show that these are also effective on the T3SS of Shigella flexneri, where they block all related forms of protein secretion so far known, as well as the epithelial cell invasion and induction of macrophage apoptosis usually demonstrated by this bacterium. Furthermore, we show the first evidence for the detrimental effect of these compounds on T3SS needle assembly, as demonstrated by increased numbers of T3S apparatuses without needles or with shorter needles. Therefore, the compounds generate a phenocopy of T3SS export apparatus mutants but with incomplete penetrance. We discuss why this would be sufficient to almost completely block the later secretion of effector proteins and how this begins to narrow the search for the molecular target of these compounds. PMID:18996990
Male monkeys use punishment and coercion to de-escalate costly intergroup fights.
Arseneau-Robar, T Jean M; Müller, Eliane; Taucher, Anouk L; van Schaik, Carel P; Bshary, Redouan; Willems, Erik P
2018-06-13
In numerous social species, males direct aggression towards female group members during intergroup fights, and this behaviour is commonly thought to function as mate guarding, even though males often target non-receptive females. In studying intergroup fights in a wild population of vervet monkeys, we found that male intragroup aggression was primarily directed towards individuals who had either just finished exhibiting, or were currently attempting to instigate intergroup aggression. Targeted females were less likely to instigate intergroup aggression in the future, indicating that male intragroup aggression functioned as coercion (when directed towards those who were currently trying to instigate a fight) and punishment (when directed towards those who had recently fought). These manipulative tactics effectively prevented intergroup encounters from escalating into fights and often de-escalated ongoing conflicts. Males who were likely sires were those most likely to use punishment/coercion, particularly when they were wounded, and, therefore, less able to protect vulnerable offspring should a risky intergroup fight erupt. This work, along with our previous finding that females use punishment and rewards to recruit males into participating in intergroup fights, highlights the inherent conflict of interest that exists between the sexes, as well as the role that social incentives can play in resolving this conflict. Furthermore, unlike other studies which have found punishment to be used asymmetrically between partners, these works represent a novel example of reciprocal punishment in a non-human animal. © 2018 The Author(s).
González-Santoyo, Isaac; González-Tokman, Daniel M; Munguía-Steyer, Roberto E; Córdoba-Aguilar, Alex
2014-01-01
Signals of fighting indicate an animal's intention to attack and so they serve to prevent costly aggressive encounters. However, according to theory, a signal that is different in design (i.e. a novel signal) but that fails to inform fighting intentions will result in negative fitness consequences for the bearer. In the present study we used males of the territorial damselfly Hetaerina americana, which have a red wing spot during territory defense that has evolved as a signal of fighting ability. By producing a novel signal (covering the red spot with blue ink) in territory owners, we investigated: a) the behavioral responses by conspecific males; b) survival cost and c) three physiological mediators of impaired survival: muscular fat reserves, muscle mass and immune ability. We predicted that males with the novel signal would be attacked more often by conspecifics as the former would fail to convey fighting ability and intentions adequately. This will result in lower survival and physiological condition for the novel signal bearers. We found that, compared to control males (males whose red spot was not changed), experimental males had reduced survival, were less able to hold a territory, and had a reduced muscle mass. It seems that spot modified males were not able to effectively communicate their territory tenancy, which may explain why they lost their defended sites. Our results provide support for theoretical models that a novel signal that fails to informing fighting ability may lead to a fitness cost for bearers.
Unpinning of spiral waves from rectangular obstacles by stimulated wave trains
NASA Astrophysics Data System (ADS)
Ponboonjaroenchai, Benjamas; Srithamma, Panatda; Kumchaiseemak, Nakorn; Sutthiopad, Malee; Müller, Stefan C.; Luengviriya, Chaiya; Luengviriya, Jiraporn
2017-09-01
Pinned spiral waves are exhibited in many excitable media. In cardiology, lengthened tachycardia correspond to propagating action potential in forms of spiral waves pinned to anatomical obstacles including veins and scares. Thus, elimination such waves is important particularly in medical treatments. We present study of unpinning of a spiral wave by a wave train initiated by periodic stimuli at a given location. The spiral wave is forced to leave the rectangular obstacle when the period of the wave train is shorter than a threshold Tunpin. For small obstacles, Tunpin decreases when the obstacle size is increased. Furthermore, Tunpin depends on the obstacle orientation with respect to the wave train propagation. For large obstacles, Tunpin is independent to the obstacle size. It implies that the orientation of the obstacle plays an important role in the unpinning of the spiral wave, especially for small rectangular obstacles.
Foster, Richard J; Buckley, John G; Whitaker, David; Elliott, David B
2016-07-01
Trips over obstacles are one of the main causes of falling in older adults, with vision playing an important role in successful obstacle negotiation. We determined whether a horizontal-vertical illusion, superimposed onto low-height obstacles to create a perceived increase in obstacle height, increased foot clearances during obstacle negotiation thus reducing the likelihood of tripping. Eleven adults (mean ± 1 SD: age 27.3 ± 5.1 years) negotiated obstacles of varying heights (3, 5, 7 cm) with four different appearance conditions; two were obstacles with a horizontal-vertical illusion (vertical stripes of different thickness) superimposed on the front, one was a plain obstacle and the fourth a plain obstacle with a horizontal black line painted on the top edge. Foot clearance parameters were compared across conditions. Both illusions led to a significant increase in foot clearance when crossing the obstacle, compared to the plain condition, irrespective of obstacle height. Superimposing a horizontal-vertical illusion onto low-height obstacles can increase foot clearance, and its use on the floor section of a double-glazing door frame for example may reduce the incidence of tripping in the home. Practitioner Summary: Low-height obstacles such as the floor section of a double-glazing door frame are potential tripping hazards. In a gait lab-based study we found that a horizontal-vertical illusion superimposed onto low-height obstacles led to significantly higher foot clearances; indicating their potential as a useful safety measure.
Fight fire with fire: Gene therapy strategies to cure HIV.
Huyghe, Jon; Magdalena, Sips; Vandekerckhove, Linos
2017-08-01
Human Immunodeficiency Virus (HIV) to date remains one of the most notorious viruses mankind has ever faced. Despite enormous investments in HIV research for more than 30 years an effective cure for HIV has been elusive. Areas covered: Combination antiretroviral therapy (cART) suppresses active viral replication, but is not able to eliminate the virus completely due to stable integration of HIV inside the host genome of infected cells and the establishment of a latent reservoir, that is insensitive to cART. Nevertheless, this latent HIV reservoir is fully capable to refuel viral replication when treatment is stopped, creating a major obstacle towards a cure for HIV. Several gene therapy approaches ranging from the generation of HIV resistant CD4 + T cells to the eradication of HIV infected cells by immune cell engineering are currently under pre-clinical and clinical investigation and may present a promising road to a cure. In this review, we focus on the status and the prospects of gene therapy strategies to cure/eradicate HIV. Expert commentary: Recent advances in gene therapy for oncology and infectious diseases indicate that gene therapy may be a feasible and very potent cure strategy, and therefore a potential game changer in the search for an effective HIV cure.
Reasons reported by African ophthalmologists for staying in Africa and for considering migrating.
Nentwich, Martin M; Schaller, Ulrich C; Klauss, Volker
2014-08-01
In sub-Sahara Africa, the shortage of ophthalmologists is a major obstacle in the struggle of fighting preventable blindness. Migration of well-trained ophthalmologists has an additional negative effect on the low number of caregivers. However, to date, the reasons affecting migration of ophthalmologists have not been completely understood. The present study evaluates reasons reported by ophthalmologists for staying in their current work setting/country and potential reasons why they might consider migrating. In the years 2009-2011, after approval was obtained from the Institutional Review Board, a questionnaire evaluating reasons for and against migration of ophthalmologists was distributed to the participants of 2-week courses in Ethiopia, Cameroon and Kenya providing continuing medical education in the field of ophthalmology. A total of 84 ophthalmologists participated in this survey. The main reasons for staying in their current region/country were good working conditions, commitment to help, possibility of further training, familial ties and general feeling of satisfaction. Professional development elsewhere and better income abroad were named as the main reasons for considering migration. Almost half of the survey participants reported good infrastructure, equipment, and consumables, which is encouraging. Programs aimed at continuing medical education of ophthalmologists to enable professional development may have an appropriate role in the establishment of an ophthalmic infrastructure which can meet patients' needs.
[Reciprocal material agency: an ecology for studies of science].
Maia, Carlos Alvarez
2017-01-01
In the historiography of the sciences there are consolidated dichotomies that can hinder better research. Fissures include mental-material, subject-object and nature-society, and the bitter conflict between relativism and realism that draws on these dichotomies and can block research. The aim of this article is to tackle these disputes, to unravel them and to move on. The proposed solution is to give consideration to the agency of material things alongside the actions of human subjects. One obstacle is presented by Latour who simulates this result by means of hylozoistic rhetoric. Here, an alternative to Latour is presented, containing no elements of animism, which gives evidence of the concrete way in which the material agency of objects participates in the doing of science, alongside humans.
ERIC Educational Resources Information Center
Rodríguez, Sonia Alejandra
2018-01-01
There is a long history of discrimination and marginalization of Chicanas/Latinas in the classroom due to xenophobia, language barriers, citizenship status, oversexualization, and much more. Through an analysis of Gloria Velasquez's ("Juanita Fights the School Board," Piñata Books, Houston, 1995) I seek to demonstrate the ways in which…
Future Role of Fire Service in Homeland Security
2008-09-01
to fight terrorism (Office of the President, 2007). In his letter to Americans in which he introduced the NSHS, President Bush explained that...structures struggling to fight non-state terrorists operating without clearly defined leadership. Furthermore, according to James R. Locker III...learned from World War II and designed to fight the Cold War. Current exposure to terrorism and terrorist cells is vastly different 16 from
FROM EXCLUSION TO INTERNATIONAL MIGRATION: THE CASE OF LATINO YOUTHS.
Sanchez R, Magaly
2006-01-01
In this article, I refer to structural tendencies reflected in the responses of excluded Latinos youths, who range from street children to radical youths (gangs or not) and finally to migrants. The latter, face unusual challenges as a result of being undocumented, forcing them to pursue mobility within a formal system that blocks their way. I review these tendencies through a "positive" lens, focusing mainly on Latino youth who are using different strategies to fight social exclusion. I aim to raise the paradoxical temporality , which indicates that as we learn and analyze more, we tend to move further away from the possibility of transforming pressing problems in society. I raise the question of how to intervene using more knowledge in the alarming situation of one of the most excluded social groups, Latino Youth and also of how to alert and visualize ways of integrating those youth who migrate and become undocumented.
FROM EXCLUSION TO INTERNATIONAL MIGRATION: THE CASE OF LATINO YOUTHS
Sanchez R, Magaly
2013-01-01
In this article, I refer to structural tendencies reflected in the responses of excluded Latinos youths, who range from street children to radical youths (gangs or not) and finally to migrants. The latter, face unusual challenges as a result of being undocumented, forcing them to pursue mobility within a formal system that blocks their way. I review these tendencies through a “positive” lens, focusing mainly on Latino youth who are using different strategies to fight social exclusion. I aim to raise the paradoxical temporality, which indicates that as we learn and analyze more, we tend to move further away from the possibility of transforming pressing problems in society. I raise the question of how to intervene using more knowledge in the alarming situation of one of the most excluded social groups, Latino Youth and also of how to alert and visualize ways of integrating those youth who migrate and become undocumented. PMID:24235783
Punt, Michiel; Bruijn, Sjoerd M; Wittink, Harriet; van de Port, Ingrid G; Wubbels, Gijs; van Dieën, Jaap H
2017-10-01
Stroke survivors often fall during walking. To reduce fall risk, gait testing and training with avoidance of virtual obstacles is gaining popularity. However, it is unknown whether and how virtual obstacle crossing is associated with fall risk. The present study assessed whether obstacle crossing characteristics are reliable and assessed differences in stroke survivors who prospectively experienced falls or no falls. We recruited twenty-nine community dwelling chronic stroke survivors. Participants crossed five virtual obstacles with increasing lengths. After a break, the test was repeated to assess test-retest reliability. For each obstacle length and trial, we determined; success rate, leading limb preference, pre and post obstacle distance, margins of stability, toe clearance, and crossing step length and speed. Subsequently, fall incidence was monitored using a fall calendar and monthly phone calls over a six-month period. Test-retest reliability was poor, but improved with increasing obstacle-length. Twelve participants reported at least one fall. No association of fall incidence with any of the obstacle crossing characteristics was found. Given the absence of height of the virtual obstacles, obstacle avoidance may have been relatively easy, allowing participants to cross obstacles in multiple ways, increasing variability of crossing characteristics and reducing the association with fall risk. These finding cast some doubt on current protocols for testing and training of obstacle avoidance in stroke rehabilitation. Copyright © 2017 Elsevier B.V. All rights reserved.
Adult play fighting and potential role of tail signals in ringtailed lemurs (Lemur catta).
Palagi, Elisabetta
2009-02-01
Adult strepsirrhines have been completely neglected in the study of animal play. I focused on adult play fighting and the role of tail-play as a signal in ringtailed lemurs (Lemur catta). Tail-play is performed during play fighting, when lemurs anoint or, more rarely, wave their tails toward the playmate. During the prereproductive period, male and female lemurs engaged in play fighting with comparable frequencies, as was expected to occur in monomorphic species such as L. catta. The dyads showing low aggression rates engaged most frequently in play fighting, and polyadic play was frequently performed. Signals seem to be important in avoiding escalation to real aggression, especially when the playfulness of performers can be misunderstood by recipients. Tail-play was most frequent (a) in the dyads with low grooming rates (low familiarity degree) and (b) during the most risky play sessions (polyadic ones). Thus, tail-play can be considered as a useful tool for play communication in ringtailed lemurs. Copyright 2009 APA, all rights reserved.
[Risk of injury in and adolescent and junior competitive karate].
Müller-Rath, R; Miltner, O; Mamarvar, M; Mumme, T
2005-12-01
Increasing professionalism in competitive karate has led to a specific injury pattern. The aim of our study was to investigate the injury pattern in junior competitive karate and to evaluate the prophylactic effect of fist padding. During the 4 (th) Junior World Championships of the World Karate Confederation (WKC) 2004 235 karate fights were observed and injury-related data were recorded. Fist padding was used in 183 fights, 52 fights were carried out without. In 22 % of all fights we saw an injury. Most of them were mild injuries of the head and face: 32 bruises of the face (13 with epistaxis), 7 facial lacerations and 3 concussions (mild brain injury). 14 fights were stopped due to an injury. Only in the category male 18 - 20 years a higher rate of injuries was seen without fist padding (shobu ippon) compared to shobu sanbon (with fist padding). The injury pattern of junior competitive karate is comparable to senior karate. Fist padding does not generally reduce the incidence or severity of injuries.
Yan, Zheping; Li, Jiyun; Zhang, Gengshi; Wu, Yi
2018-02-02
A novel real-time reaction obstacle avoidance algorithm (RRA) is proposed for autonomous underwater vehicles (AUVs) that must adapt to unknown complex terrains, based on forward looking sonar (FLS). To accomplish this algorithm, obstacle avoidance rules are planned, and the RRA processes are split into five steps Introduction only lists 4 so AUVs can rapidly respond to various environment obstacles. The largest polar angle algorithm (LPAA) is designed to change detected obstacle's irregular outline into a convex polygon, which simplifies the obstacle avoidance process. A solution is designed to solve the trapping problem existing in U-shape obstacle avoidance by an outline memory algorithm. Finally, simulations in three unknown obstacle scenes are carried out to demonstrate the performance of this algorithm, where the obtained obstacle avoidance trajectories are safety, smooth and near-optimal.
Institutional Memory and the US Air Force
2016-01-01
38 | Air & Space Power Journal Institutional Memory and the US Air Force Lt Col Daniel J. Brown, USAF Disclaimer: The views and opinions expressed...national defense. After each ad- vance is tested in combat, a new round of intellectual sparring commences regarding Summer 2016 | 39 Institutional Memory ...the service’s institutional memory of how it fights and what it fights with—the ways and means of war fighting. Critical to maintaining its
Fight Crime: Invest in Kids Survey of Police Chief Views of Effective Crime-Fighting Strategies.
ERIC Educational Resources Information Center
McDevitt, Jack; Baum, Katrina
This report provides, in tabular and graphic format, the results of a national poll conducted for the Fight Crime: Invest in Kids campaign. The survey sought opinions of 780 police chiefs: all chiefs from cities with populations over 100,000, a sample of 288 chiefs from cities of less than 25,000, and a sample of 292 chiefs from cities of between…
ERIC Educational Resources Information Center
van Noije, Lonneke; Wittebrood, Karin
2010-01-01
How effective are policy interventions to fight crime and how valid is the policy theory that underlies them? This is the twofold research question addressed in this article, which presents an evidence-based evaluation of Dutch social safety policy. By bridging the gap between actual effects and assumed effects, this study seeks to make fuller use…
Prehospital Use of Ketamine in Battlefield Analgesia
2012-03-08
15 mg PO once a day - Tylenol , 650-mg bilayer caplet, 2 PO every 8 hours b. Unable to fight: Note: Have naloxone readily...possible after the wound is sustained. - Mobic, 15 mg PO once a day - Tylenol , 650-mg bilayer caplet, 2 PO every 8 hours b. Unable to fight... Tylenol , 650-mg bilayered caplet, 2 PO every 8 hours b. Unable to fight: Note: Have naloxone readily available whenever
Wang, Jianli; Tai, Fadao; Yan, Xingfu; Yu, Peng
2012-11-01
Although early paternal deprivation significantly affects offspring behavioral and neuroendocrine development, the link between paternal deprivation and social play behavior remains unclear. Mandarin voles (Microtus mandarinus) are socially monogamous and display bi-paternal care. The present study examined the development of social play in juvenile male mandarin voles and the paternal influence on play-fighting, vasopressin- and oxytocin-immunoreactive neurons and serum corticosterone and testosterone levels. The results show that social play was more pronounced during postnatal days 28-35, differing from the ontogenetic pattern of other forms of social behavior. On postnatal day 35, the peak in play-fighting activity, paternal deprivation reduced boxing/wrestling levels and vasopressin-immunoreactive neurons in the anterior hypothalamus and oxytocin-immunoreactive neurons in the paraventricular nucleus, but increased vasopressin-immunoreactive neurons in the paraventricular nucleus and corticosterone levels. These results suggest that mandarin voles engage in social play according to an inverted U-shaped curve in ontogeny, and paternal deprivation influences the development of offspring play-fighting; hypothalamic vasopressin, oxytocin and serum corticosterone may play a modulatory role in the alteration of play-fighting elicited by paternal deprivation; decreased play-fighting may correlate with depressed vasopressin levels in the anterior hypothalamus.
Loffing, Florian; Hagemann, Norbert
2015-05-01
The fighting hypothesis proposes that left-oriented athletes enjoy a negative frequency-dependent advantage in combat sports such as boxing. Supporting evidence, however, is restricted to cross-sectional frequency data from small samples. Here, we examined the incidence and fight records of 2,403 left- and right-oriented fighters who were listed in the annual ratings of professional boxing from 1924 to 2012. Unexpectedly, left-oriented boxers were overrepresented in no more than 7 of the 89 years considered, their percentages varied up to 30% and increased over the entire period, and frequencies varied substantially between weight divisions. In support of the fighting hypothesis, lose-win ratios indicated larger fighting strength in left- compared to right-oriented boxers, which, however, was not reflected in different proportions of wins and losses by knockout. Our findings are partly consistent with an assumed left-oriented fighters' advantage in combat sports. Such advantage could be explained by negative frequency-dependent selection mechanisms; however, our study also revealed potential limits of the fighting hypothesis such that alternative explanations cannot be fully excluded. We propose that interference by factors not related to performance could also limit the suitability of data from elite sporting competition for testing evolutionary models of human handedness.
Stepping back to see the big picture: when obstacles elicit global processing.
Marguc, Janina; Förster, Jens; Van Kleef, Gerben A
2011-11-01
Can obstacles prompt people to look at the "big picture" and open up their minds? Do the cognitive effects of obstacles extend beyond the tasks with which they interfere? These questions were addressed in 6 studies involving both physical and nonphysical obstacles and different measures of global versus local processing styles. Perceptual scope increased after participants solved anagrams in the presence, rather than the absence, of an auditory obstacle (random words played in the background; Study 1), particularly among individuals low in volatility (i.e., those who are inclined to stay engaged and finish what they do; Study 4). It also increased immediately after participants encountered a physical obstacle while navigating a maze (Study 3A) and when compared with doing nothing (Study 3B). Conceptual scope increased after participants solved anagrams while hearing random numbers framed as an "obstacle to overcome" rather than a "distraction to ignore" (Study 2) and after participants navigated a maze with a physical obstacle, compared with a maze without a physical obstacle, but only when trait (Study 5) or state (Study 6) volatility was low. Results suggest that obstacles trigger an "if obstacle, then start global processing" response, primarily when people are inclined to stay engaged and finish ongoing activities. Implications for dealing with life's obstacles and related research are discussed.
Šmigelskas, Kastytis; Vaičiūnas, Tomas; Lukoševičiūtė, Justė; Malinowska-Cieślik, Marta; Melkumova, Marina; Movsesyan, Eva; Zaborskis, Apolinaras
2018-04-26
Background: This study aims to explore how sufficient social support can act as a possible preventive factor against fighting and bullying in school-aged children in 9 European countries. Methods : Data for this study were collected during the 2013/2014 Health Behaviour in School-aged Children (HBSC) survey. The sample consisted of 9 European countries, involving 43,667 school children in total, aged 11, 13 and 15 years. The analysed data focus on social context (relations with family, peers, and school) as well as risk behaviours such as smoking, drunkenness, fighting and bullying in adolescents. The relationships between social support and violent behaviour variables were estimated using multiple regression models and multivariate analyses. Results : Bullying, across 9 countries, was more prevalent than fighting, except for Armenia, Israel, and Poland. The prevalence among countries differed considerably, with fighting being most expressed in Armenia and bullying—in Latvia and Lithuania. The strongest risk factors for bullying and fighting were male gender (less expressed for bullying), smoking and alcohol consumption. In addition, for bullying the social support was similarly strong factor like above-mentioned factors, while for fighting—less significant, but still independent. All forms of social support were significantly relate with lower violent behaviour of school children, and family support was associated most strongly. Regardless the socioeconomic, historical, and cultural differences among selected countries, the enhancement and reinforcement of the social support from possible many different resources should be taken into consideration in prevention programs against school violence behaviours.
Sharma, Bimala; Nam, Eun Woo; Kim, Ha Yun; Kim, Jong Koo
2016-01-01
Background Witnessing inter-parental violence and bullying victimization is common for many children and adolescents. This study examines the role of witnessing inter-parental violence and bullying victimization in involvement in physical fighting among Peruvian adolescents. Methods A cross-sectional study was conducted among 1,368 randomly selected adolescents in 2015. We conducted logistic regression analyses to obtain crude and adjusted odds ratios with 95% confidence intervals for involvement in fighting among male and female adolescents. Results Among all adolescents, 35.8% had been involved in fighting in the last 12 months, 32.9% had been victim of verbal bullying and 37.9% had been the victim of physical bullying. Additionally, 39.2% and 27.8% of adolescents witnessed violence against their mother and father, respectively, at least once in their lives. Multivariate logistic regression analyses found that late adolescence, participation in economic activities, being the victim of verbal bullying, stress, and witnessing violence against the father among male adolescents, and self-rated academic performance and being the victim of physical or verbal bullying among female adolescents were associated with higher odds of being involved in fighting. Conclusion Verbal bullying victimization and witnessing violence against the father in males and bullying victimization in females were associated with greater odds of adolescents being involved in fighting. Creating a non-violent environment at both home and school would be an effective strategy for reducing fighting among the adolescent population. PMID:27358837
Obstacles for Teachers to Integrate Technology with Instruction
ERIC Educational Resources Information Center
Alenezi, Abdullah
2017-01-01
This paper covers type one and two educational obstacles in using technology in the classrooms, and considering those obstacles tries to find the answer to the following overarching research question which can help to gauge some obstacles for the educational technology integration for elementary and high school education: What obstacles do…
Influences of periodic mechanical deformation on pinned spiral waves
NASA Astrophysics Data System (ADS)
Chen, Jiang-Xing; Peng, Liang; Zheng, Qiang; Zhao, Ye-Hua; Ying, He-Ping
2014-09-01
In a generic model of excitable media, we study the behavior of spiral waves interacting with obstacles and their dynamics under the influences of simple periodic mechanical deformation (PMD). Depending on the characteristics of the obstacles, i.e., size and excitability, the rotation of a pinned spiral wave shows different scenarios, e.g., embedding into or anchoring on an obstacle. Three different drift phenomena induced by PMD are observed: scattering on small partial-excitable obstacles, meander-induced unpinning on big partial-excitable obstacles, and drifting around small unexcitable obstacles. Their underlying mechanisms are discussed. The dependence of the threshold amplitude of PMD on the characteristics of the obstacles to successfully remove pinned spiral waves on big partial-excitable obstacles is studied.
Vision Based Obstacle Detection in Uav Imaging
NASA Astrophysics Data System (ADS)
Badrloo, S.; Varshosaz, M.
2017-08-01
Detecting and preventing incidence with obstacles is crucial in UAV navigation and control. Most of the common obstacle detection techniques are currently sensor-based. Small UAVs are not able to carry obstacle detection sensors such as radar; therefore, vision-based methods are considered, which can be divided into stereo-based and mono-based techniques. Mono-based methods are classified into two groups: Foreground-background separation, and brain-inspired methods. Brain-inspired methods are highly efficient in obstacle detection; hence, this research aims to detect obstacles using brain-inspired techniques, which try to enlarge the obstacle by approaching it. A recent research in this field, has concentrated on matching the SIFT points along with, SIFT size-ratio factor and area-ratio of convex hulls in two consecutive frames to detect obstacles. This method is not able to distinguish between near and far obstacles or the obstacles in complex environment, and is sensitive to wrong matched points. In order to solve the above mentioned problems, this research calculates the dist-ratio of matched points. Then, each and every point is investigated for Distinguishing between far and close obstacles. The results demonstrated the high efficiency of the proposed method in complex environments.
Strategies for obstacle avoidance during walking in the cat.
Chu, Kevin M I; Seto, Sandy H; Beloozerova, Irina N; Marlinski, Vladimir
2017-08-01
Avoiding obstacles is essential for successful navigation through complex environments. This study aimed to clarify what strategies are used by a typical quadruped, the cat, to avoid obstacles during walking. Four cats walked along a corridor 2.5 m long and 25 or 15 cm wide. Obstacles, small round objects 2.5 cm in diameter and 1 cm in height, were placed on the floor in various locations. Movements of the paw were recorded with a motion capture and analysis system (Visualeyez, PTI). During walking in the wide corridor, cats' preferred strategy for avoiding a single obstacle was circumvention, during which the stride direction changed while stride duration and swing-to-stride duration ratio were preserved. Another strategy, stepping over the obstacle, was used during walking in the narrow corridor, when lateral deviations of walking trajectory were restricted. Stepping over the obstacle involved changes in two consecutive strides. The stride preceding the obstacle was shortened, and swing-to-stride ratio was reduced. The obstacle was negotiated in the next stride of increased height and normal duration and swing-to-stride ratio. During walking on a surface with multiple obstacles, both strategies were used. To avoid contact with the obstacle, cats placed the paw away from the object at a distance roughly equal to the diameter of the paw. During obstacle avoidance cats prefer to alter muscle activities without altering the locomotor rhythm. We hypothesize that a choice of the strategy for obstacle avoidance is determined by minimizing the complexity of neuro-motor processes required to achieve the behavioral goal. NEW & NOTEWORTHY In a study of feline locomotor behavior we found that the preferred strategy to avoid a small obstacle is circumvention. During circumvention, stride direction changes but length and temporal structure are preserved. Another strategy, stepping over the obstacle, is used in narrow walkways. During overstepping, two strides adjust. A stride preceding the obstacle decreases in length and duration. The following stride negotiating the obstacle increases in height while retaining normal temporal structure and nearly normal length. Copyright © 2017 the American Physiological Society.
Fighting in the Gray Zone: A Strategy to Close the Preemption Gap
2004-06-12
FIGHTING IN THE GRAY ZONE: A STRATEGY TO CLOSE THE PREEMPTION GAP Joanne M. Fish, Commander, USN Samuel J. McCraw, Lieutenant Colonel...SUBTITLE FIGHTING IN THE GRAY ZONE: A STRATEGY TO CLOSE THE PREEMPTION GAP 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...Classical) Forcible Counterproliferation Figure 10: WMD Acquisition in the Gray Zone FORCIBLE COUNTERPROLIFERATION: CLOSING THE STRATEGY GAP The
Prehospital Use of Ketamine in Battlefield Analgesia 2012-03
2012-03-08
15 mg PO once a day - Tylenol , 650-mg bilayer caplet, 2 PO every 8 hours b. Unable to fight: Note: Have naloxone readily...possible after the wound is sustained. - Mobic, 15 mg PO once a day - Tylenol , 650-mg bilayer caplet, 2 PO every 8 hours b. Unable to fight... Tylenol , 650-mg bilayered caplet, 2 PO every 8 hours b. Unable to fight: Note: Have naloxone readily available whenever
US Coast Guard lightweight fire-fighting module
NASA Astrophysics Data System (ADS)
1980-05-01
The U.S. Coast Guard Fire-fighting Module developed for the purpose of fighting fires in harbors and on ships is described. The module can be lifted by a dockside crane or helicopter and placed on the deck of a patrol boat or cutter for transportation to the scene of the fire. At the fire the module can be set up and put in operation by a crew of two in approximately fifteen minutes. Once in operation the module will deliver water to two fire nozzles at a pressure of 150 psi and a flow rate of 2000 gpm. Sufficient fuel is carried in the module for three hours of continuous operation. A record of the development of the fire fighting module is also presented.
US Coast Guard lightweight fire-fighting module
NASA Technical Reports Server (NTRS)
1980-01-01
The U.S. Coast Guard Fire-fighting Module developed for the purpose of fighting fires in harbors and on ships is described. The module can be lifted by a dockside crane or helicopter and placed on the deck of a patrol boat or cutter for transportation to the scene of the fire. At the fire the module can be set up and put in operation by a crew of two in approximately fifteen minutes. Once in operation the module will deliver water to two fire nozzles at a pressure of 150 psi and a flow rate of 2000 gpm. Sufficient fuel is carried in the module for three hours of continuous operation. A record of the development of the fire fighting module is also presented.
Aviation obstacle auto-extraction using remote sensing information
NASA Astrophysics Data System (ADS)
Zimmer, N.; Lugsch, W.; Ravenscroft, D.; Schiefele, J.
2008-10-01
An Obstacle, in the aviation context, may be any natural, man-made, fixed or movable object, permanent or temporary. Currently, the most common way to detect relevant aviation obstacles from an aircraft or helicopter for navigation purposes and collision avoidance is the use of merged infrared and synthetic information of obstacle data. Several algorithms have been established to utilize synthetic and infrared images to generate obstacle information. There might be a situation however where the system is error-prone and may not be able to consistently determine the current environment. This situation can be avoided when the system knows the true position of the obstacle. The quality characteristics of the obstacle data strongly depends on the quality of the source data such as maps and official publications. In some countries such as newly industrializing and developing countries, quality and quantity of obstacle information is not available. The aviation world has two specifications - RTCA DO-276A and ICAO ANNEX 15 Ch. 10 - which describe the requirements for aviation obstacles. It is essential to meet these requirements to be compliant with the specifications and to support systems based on these specifications, e.g. 3D obstacle warning systems where accurate coordinates based on WGS-84 is a necessity. Existing aerial and satellite or soon to exist high quality remote sensing data makes it feasible to think about automated aviation obstacle data origination. This paper will describe the feasibility to auto-extract aviation obstacles from remote sensing data considering limitations of image and extraction technologies. Quality parameters and possible resolution of auto-extracted obstacle data will be discussed and presented.
Software designs of image processing tasks with incremental refinement of computation.
Anastasia, Davide; Andreopoulos, Yiannis
2010-08-01
Software realizations of computationally-demanding image processing tasks (e.g., image transforms and convolution) do not currently provide graceful degradation when their clock-cycles budgets are reduced, e.g., when delay deadlines are imposed in a multitasking environment to meet throughput requirements. This is an important obstacle in the quest for full utilization of modern programmable platforms' capabilities since worst-case considerations must be in place for reasonable quality of results. In this paper, we propose (and make available online) platform-independent software designs performing bitplane-based computation combined with an incremental packing framework in order to realize block transforms, 2-D convolution and frame-by-frame block matching. The proposed framework realizes incremental computation: progressive processing of input-source increments improves the output quality monotonically. Comparisons with the equivalent nonincremental software realization of each algorithm reveal that, for the same precision of the result, the proposed approach can lead to comparable or faster execution, while it can be arbitrarily terminated and provide the result up to the computed precision. Application examples with region-of-interest based incremental computation, task scheduling per frame, and energy-distortion scalability verify that our proposal provides significant performance scalability with graceful degradation.
Physiological and Technical-tactical Analysis in Brazilian Jiu-jitsu Competition.
Andreato, Leonardo V; Franchini, Emerson; de Moraes, Solange M F; Pastório, Juliana J; da Silva, Danilo F; Esteves, João V D C; Branco, Braulio H M; Romero, Paulo V Ds; Machado, Fabiana A
2013-06-01
The present study aims at investigating the physiological response and technical-tactical parameters in Brazilian jiu-jitsu competition. The study included 35 male Brazilian jiu-jitsu athletes (adult category, body mass: 80.2 ± 13.0 kg), graded from white to brown belt, during combats fought at regional level. Twenty-two fights were analyzed in terms of technique and time structure. Blood glucose, lactate and maximal isometric grip strength were determined before and after the fights. The rate of perceived exertion was also assessed after the fight, using the 6-20 Borg rating. The fights were recorded and the following variables were determined: the exertion/pause ratio and subjective intensity of actions, categorized between low and high intensity. The results indicated that during Brazilian jiu-jitsu fights, the glycolytic pathway is only moderately activated (lactate before: 4.4 (4.0 - 4.6) mmol/L, after: 10.1 (8.0 - 11.3) mmol/L; glucose before: 112.4 ± 22.3 mg/dL, after: 130.5 ± 31.0 mg/dL). The exertion during the fight resulted in significant reductions in handgrip strength (right hand grip before: 45.9 ± 10.3 kgf, after: 40.1 ± 9.5 kgf; left hand grip before: 44.2 ± 11.1 kgf, after: 37.0 ± 10.2 kgf). The athletes rated the fight as hard: 15 (13 - 15). Effort/pause ratio was 6:1, while high-intensity actions lasted approximately 4 s, resulting in a low/high intensity? ratio of 8:1. It is recommended that coaches direct the training loads to simulate the energy demand imposed by the competitive matches, activating moderately the glycolytic pathway. Moreover, the time structure of combats can be used to prescribe both physical and technical-tactical training.
A multimodal micro air vehicle for autonomous flight in near-earth environments
NASA Astrophysics Data System (ADS)
Green, William Edward
Reconnaissance, surveillance, and search-and-rescue missions in near-Earth environments such as caves, forests, and urban areas pose many new challenges to command and control (C2) teams. Of great significance is how to acquire situational awareness when access to the scene is blocked by enemy fire, rubble, or other occlusions. Small bird-sized aerial robots are expendable and can fly over obstacles and through small openings to assist in the acquisition and distribution of intelligence. However, limited flying space and densely populated obstacle fields requires a vehicle that is capable of hovering, but also maneuverable. A secondary flight mode was incorporated into a fixed-wing aircraft to preserve its maneuverability while adding the capability of hovering. An inertial measurement sensor and onboard flight control system were interfaced and used to transition the hybrid prototype from cruise to hover flight and sustain a hover autonomously. Furthermore, the hovering flight mode can be used to maneuver the aircraft through small openings such as doorways. An ultrasonic and infrared sensor suite was designed to follow exterior building walls until an ingress route was detected. Reactive control was then used to traverse the doorway and gather reconnaissance. Entering a dangerous environment to gather intelligence autonomously will provide an invaluable resource to any C2 team. The holistic approach of platform development, sensor suite design, and control serves as the philosophy of this work.
Autonomous Lawnmower using FPGA implementation.
NASA Astrophysics Data System (ADS)
Ahmad, Nabihah; Lokman, Nabill bin; Helmy Abd Wahab, Mohd
2016-11-01
Nowadays, there are various types of robot have been invented for multiple purposes. The robots have the special characteristic that surpass the human ability and could operate in extreme environment which human cannot endure. In this paper, an autonomous robot is built to imitate the characteristic of a human cutting grass. A Field Programmable Gate Array (FPGA) is used to control the movements where all data and information would be processed. Very High Speed Integrated Circuit (VHSIC) Hardware Description Language (VHDL) is used to describe the hardware using Quartus II software. This robot has the ability of avoiding obstacle using ultrasonic sensor. This robot used two DC motors for its movement. It could include moving forward, backward, and turning left and right. The movement or the path of the automatic lawn mower is based on a path planning technique. Four Global Positioning System (GPS) plot are set to create a boundary. This to ensure that the lawn mower operates within the area given by user. Every action of the lawn mower is controlled by the FPGA DE' Board Cyclone II with the help of the sensor. Furthermore, Sketch Up software was used to design the structure of the lawn mower. The autonomous lawn mower was able to operate efficiently and smoothly return to coordinated paths after passing the obstacle. It uses 25% of total pins available on the board and 31% of total Digital Signal Processing (DSP) blocks.
Understanding why a Ground Combat Vehicle that Carries Nine Dismounts is Important to the Army
2013-01-01
BFV Bradley Fighting Vehicle BLUF Bottom Line Up Front BMP Boyevaya Mashina Pekhoty (infantry fighting vehicle) COIN counterinsurgency DIV 86...the introduction of the Bradley Fighting Vehicle ( BFV ).15 It is important to note that the standardization of the nine-man infantry squad resulting...integrated the BFV into its mechanized infantry formations. 29 Today’s squad with nine soldiers is smaller by two than the mid-50s squad but is otherwise
Donald N. Matthews
1940-01-01
Fire fighting is still largely a hand-work job in the heavy cover and fuel conditions and rugged topography of the Douglas fir region, in spite of recent advances that have been made in %he use of machinery. Controlling a fire in this region requires immense amounts of work per unit of fire perimeter, so that large numbers of men are required to attack all but the...
2006-05-26
Winning the Counterinsurgency Fight in Iraq: The Role of Political Culture in Counterinsurgency Warfare 2003-2006 in Iraq A Monograph by Major...Counterinsurgency Fight in Iraq: The Role of Political Culture in Counterinsurgency Warfare 2003-2006 in Iraq 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5e...14. ABSTRACT This monograph provides insight into the importance of political culture in relation to developing a counterinsurgency strategy. This
Research on UAV Intelligent Obstacle Avoidance Technology During Inspection of Transmission Line
NASA Astrophysics Data System (ADS)
Wei, Chuanhu; Zhang, Fei; Yin, Chaoyuan; Liu, Yue; Liu, Liang; Li, Zongyu; Wang, Wanguo
Autonomous obstacle avoidance of unmanned aerial vehicle (hereinafter referred to as UAV) in electric power line inspection process has important significance for operation safety and economy for UAV intelligent inspection system of transmission line as main content of UAV intelligent inspection system on transmission line. In the paper, principles of UAV inspection obstacle avoidance technology of transmission line are introduced. UAV inspection obstacle avoidance technology based on particle swarm global optimization algorithm is proposed after common obstacle avoidance technologies are studied. Stimulation comparison is implemented with traditional UAV inspection obstacle avoidance technology which adopts artificial potential field method. Results show that UAV inspection strategy of particle swarm optimization algorithm, adopted in the paper, is prominently better than UAV inspection strategy of artificial potential field method in the aspects of obstacle avoidance effect and the ability of returning to preset inspection track after passing through the obstacle. An effective method is provided for UAV inspection obstacle avoidance of transmission line.
Carmenate, Tania; Ortíz, Yaquelín; Enamorado, Michel; García-Martínez, Karina; Avellanet, Janet; Moreno, Ernesto; Graça, Luis; León, Kalet
2018-05-15
IL-2 is critical for peripheral tolerance mediated by regulatory T (Treg) cells, which represent an obstacle for effective cancer immunotherapy. Although IL-2 is important for effector (E) T cell function, it has been hypothesized that therapies blocking IL-2 signals weaken Treg cell activity, promoting immune responses. This hypothesis has been partially tested using anti-IL-2 or anti-IL-2R Abs with antitumor effects that cannot be exclusively attributed to lack of IL-2 signaling in vivo. In this work, we pursued an alternative strategy to block IL-2 signaling in vivo, taking advantage of the trimeric structure of the IL-2R. We designed an IL-2 mutant that conserves the capacity to bind to the αβ-chains of the IL-2R but not to the γ c -chain, thus having a reduced signaling capacity. We show our IL-2 mutein inhibits IL-2 Treg cell-dependent differentiation and expansion. Moreover, treatment with IL-2 mutein reduces Treg cell numbers and impairs tumor growth in mice. A mathematical model was used to better understand the effect of the mutein on Treg and E T cells, suggesting suitable strategies to improve its design. Our results show that it is enough to transiently inhibit IL-2 signaling to bias E and Treg cell balance in vivo toward immunity. Copyright © 2018 by The American Association of Immunologists, Inc.
Asymmetric forceps increase fighting success among males of similar size in the maritime earwig
Munoz, Nicole E.; Zink, Andrew G.
2012-01-01
Extreme asymmetric morphologies are hypothesized to serve an adaptive function that counteracts sexual selection for symmetry. However direct tests of function for asymmetries are lacking, particularly in the context of animal weapons. The weapon of the maritime earwig, Anisolabis maritima, exhibits sizeable variation in the extent of directional asymmetry within and across body sizes, making it an ideal candidate for investigating the function of asymmetry. In this study, we characterized the extent of weapon asymmetry, characterized the manner in which asymmetric weapons are used in contests, staged dyadic contests between males of different size classes and analyzed the correlates of fighting success. In contests between large males, larger individuals won more fights and emerged as the dominant male. In contests between small males, however, weapon asymmetry was more influential in predicting overall fighting success than body size. This result reveals an advantage of asymmetric weaponry among males that are below the mean size in the population. A forceps manipulation experiment suggests that asymmetry may be an indirect, correlate of a morphologically independent factor that affects fighting ability. PMID:22984320
Umbers, Kate D. L.; Osborne, Louise; Keogh, J. Scott
2012-01-01
Empirical studies of the determinants of contests have been attempting to unravel the complexity of animal contest behaviour for decades. This complexity requires that experiments incorporate multiple determinants into studies to tease apart their relative effects. In this study we examined the complex contest behaviour of the tawny dragon (Ctenophorus decresii), a territorial agamid lizard, with the specific aim of defining the factors that determine contest outcome. We manipulated the relative size and residency status of lizards in contests to weight their importance in determining contest outcome. We found that size, residency and initiating a fight were all important in determining outcomes of fights. We also tested whether residency or size was important in predicting the status of lizard that initiated a fight. We found that residency was the most important factor in predicting fight initiation. We discuss the effects of size and residency status in context of previous studies on contests in tawny dragons and other animals. Our study provides manipulative behavioural data in support of the overriding effects of residency on initiation fights and winning them. PMID:23077558
Yan, Zheping; Li, Jiyun; Zhang, Gengshi; Wu, Yi
2018-01-01
A novel real-time reaction obstacle avoidance algorithm (RRA) is proposed for autonomous underwater vehicles (AUVs) that must adapt to unknown complex terrains, based on forward looking sonar (FLS). To accomplish this algorithm, obstacle avoidance rules are planned, and the RRA processes are split into five steps Introduction only lists 4 so AUVs can rapidly respond to various environment obstacles. The largest polar angle algorithm (LPAA) is designed to change detected obstacle’s irregular outline into a convex polygon, which simplifies the obstacle avoidance process. A solution is designed to solve the trapping problem existing in U-shape obstacle avoidance by an outline memory algorithm. Finally, simulations in three unknown obstacle scenes are carried out to demonstrate the performance of this algorithm, where the obtained obstacle avoidance trajectories are safety, smooth and near-optimal. PMID:29393915
Range Sensor-Based Efficient Obstacle Avoidance through Selective Decision-Making.
Shim, Youngbo; Kim, Gon-Woo
2018-03-29
In this paper, we address a collision avoidance method for mobile robots. Many conventional obstacle avoidance methods have been focused solely on avoiding obstacles. However, this can cause instability when passing through a narrow passage, and can also generate zig-zag motions. We define two strategies for obstacle avoidance, known as Entry mode and Bypass mode. Entry mode is a pattern for passing through the gap between obstacles, while Bypass mode is a pattern for making a detour around obstacles safely. With these two modes, we propose an efficient obstacle avoidance method based on the Expanded Guide Circle (EGC) method with selective decision-making. The simulation and experiment results show the validity of the proposed method.
Salomir, Rares; Petrusca, Lorena; Auboiroux, Vincent; Muller, Arnaud; Vargas, Maria-Isabel; Morel, Denis R; Goget, Thomas; Breguet, Romain; Terraz, Sylvain; Hopple, Jerry; Montet, Xavier; Becker, Christoph D; Viallon, Magalie
2013-06-01
The treatment of liver cancer is a major public health issue because the liver is a frequent site for both primary and secondary tumors. Rib heating represents a major obstacle for the application of extracorporeal focused ultrasound to liver ablation. Magnetic resonance (MR)-guided external shielding of acoustic obstacles (eg, the ribs) was investigated here to avoid unwanted prefocal energy deposition in the pathway of the focused ultrasound beam. Ex vivo and in vivo (7 female sheep) experiments were performed in this study. Magnetic resonance-guided high-intensity focused ultrasound (MRgHIFU) was performed using a randomized 256-element phased-array transducer (f∼1 MHz) and a 3-T whole-body clinical MR scanner. A physical mask was inserted in the prefocal beam pathway, external to the body, to block the energy normally targeted on the ribs. The effectiveness of the reflecting material was investigated by characterizing the efficacy of high-intensity focused ultrasound beam reflection and scattering on its surface using Schlieren interferometry. Before high-intensity focused ultrasound sonication, the alignment of the protectors with the conical projections of the ribs was required and achieved in multiple steps using the embedded graphical tools of the MR scanner. Multiplanar near real-time MR thermometry (proton resonance frequency shift method) enabled the simultaneous visualization of the local temperature increase at the focal point and around the exposed ribs. The beam defocusing due to the shielding was evaluated from the MR acoustic radiation force impulse imaging data. Both MR thermometry (performed with hard absorber positioned behind a full-aperture blocking shield) and Schlieren interferometry indicated a very good energy barrier of the shielding material. The specific temperature contrast between rib surface (spatial average) and focus, calculated at the end point of the MRgHIFU sonication, with protectors vs no protectors, indicated an important reduction of the temperature elevation at the ribs' surface, typically by 3.3 ± 0.4 in vivo. This was translated into an exponential reduction in thermal dose by several orders of magnitude. The external shielding covering the full conical shadow of the ribs was more effective when the protectors could be placed close to the ribs' surface and had a tendency to lose its efficiency when placed further from the ribs. Hepatic parenchyma was safely ablated in vivo using this rib-sparing strategy and single-focus independent sonications. A readily available, MR-compatible, effective, and cost-competitive method for rib protection in transcostal MRgHIFU was validated in this study, using specific reflective strips. The current approach permitted safe intercostal ablation of small volumes (0.7 mL) of liver parenchyma.
... Posts America Is Great at Fighting Terrorism, but Terror Is Alive and Well Can Vaping Help Smokers ... Commentary: America Is Great at Fighting Terrorism, but Terror Is Alive and Well William Shadel @william_shadel ...
NASA Astrophysics Data System (ADS)
Togun, Hussein
2016-03-01
This paper presents a numerical investigate on CuO-water nano-fluid and heat transfer in a backward-facing step with and without obstacle. The range of Reynolds number varied from 75 to 225 with volume fraction on CuO nanoparticles varied from 1 to 4 % at constant heat flux was investigated. Continuity, momentum, and energy equations with finite volume method in two dimensions were employed. Four different configurations of backward-facing step (without obstacle, with obstacle of 1.5 mm, with obstacle of 3 mm, with obstacle of 4.5 mm) were considered to find the best thermal performance. The results show that the maximum augmentation in heat transfer was about 22 % for backward-facing step with obstacle of 4.5 mm and using CuO nanoparticles at Reynolds number of 225 compared with backward-facing step without obstacle. It is also observed that increase in size of recirculation region with increase of height obstacle on the channel wall has remarkable effect on thermal performance. The results also found that increases in Reynolds number, height obstacle, and volume fractions of CuO nanoparticles lead to increase of pressure drop.
Obstacle avoidance handling and mixed integer predictive control for space robots
NASA Astrophysics Data System (ADS)
Zong, Lijun; Luo, Jianjun; Wang, Mingming; Yuan, Jianping
2018-04-01
This paper presents a novel obstacle avoidance constraint and a mixed integer predictive control (MIPC) method for space robots avoiding obstacles and satisfying physical limits during performing tasks. Firstly, a novel kind of obstacle avoidance constraint of space robots, which needs the assumption that the manipulator links and the obstacles can be represented by convex bodies, is proposed by limiting the relative velocity between two closest points which are on the manipulator and the obstacle, respectively. Furthermore, the logical variables are introduced into the obstacle avoidance constraint, which have realized the constraint form is automatically changed to satisfy different obstacle avoidance requirements in different distance intervals between the space robot and the obstacle. Afterwards, the obstacle avoidance constraint and other system physical limits, such as joint angle ranges, the amplitude boundaries of joint velocities and joint torques, are described as inequality constraints of a quadratic programming (QP) problem by using the model predictive control (MPC) method. To guarantee the feasibility of the obtained multi-constraint QP problem, the constraints are treated as soft constraints and assigned levels of priority based on the propositional logic theory, which can realize that the constraints with lower priorities are always firstly violated to recover the feasibility of the QP problem. Since the logical variables have been introduced, the optimization problem including obstacle avoidance and system physical limits as prioritized inequality constraints is termed as MIPC method of space robots, and its computational complexity as well as possible strategies for reducing calculation amount are analyzed. Simulations of the space robot unfolding its manipulator and tracking the end-effector's desired trajectories with the existence of obstacles and physical limits are presented to demonstrate the effectiveness of the proposed obstacle avoidance strategy and MIPC control method of space robots.
NASA Astrophysics Data System (ADS)
Bowling, Daniel L.
2015-06-01
In everyday use, emotion typically refers to conscious feelings. It feels like something to be happy or sad, afraid or angry. These emotions have qualia. That qualia are so central to what we mean by emotion makes emotion research both exciting and frustrating. Exciting because understanding how the brain gives rise to qualia is a fundamental goal of neuroscience, and frustrating because despite centuries of inquiry, qualia continue to defy a mechanistic explanation. But this obstacle has not completely blocked progress because there are other aspects of emotion - behavioral and physiological - that are more accessible to research, and the study of these has produced considerable advances in our understanding of how emotions work [13].
NASA Astrophysics Data System (ADS)
Stefferson, Michael W.; Norris, Samantha L.; Vernerey, Franck J.; Betterton, Meredith D.; E Hough, Loren
2017-08-01
Crowded environments modify the diffusion of macromolecules, generally slowing their movement and inducing transient anomalous subdiffusion. The presence of obstacles also modifies the kinetics and equilibrium behavior of tracers. While previous theoretical studies of particle diffusion have typically assumed either impenetrable obstacles or binding interactions that immobilize the particle, in many cellular contexts bound particles remain mobile. Examples include membrane proteins or lipids with some entry and diffusion within lipid domains and proteins that can enter into membraneless organelles or compartments such as the nucleolus. Using a lattice model, we studied the diffusive movement of tracer particles which bind to soft obstacles, allowing tracers and obstacles to occupy the same lattice site. For sticky obstacles, bound tracer particles are immobile, while for slippery obstacles, bound tracers can hop without penalty to adjacent obstacles. In both models, binding significantly alters tracer motion. The type and degree of motion while bound is a key determinant of the tracer mobility: slippery obstacles can allow nearly unhindered diffusion, even at high obstacle filling fraction. To mimic compartmentalization in a cell, we examined how obstacle size and a range of bound diffusion coefficients affect tracer dynamics. The behavior of the model is similar in two and three spatial dimensions. Our work has implications for protein movement and interactions within cells.
Agriculture’s Soil Conservation Programs Miss Full Potential in the Fight against Soil Erosion.
1983-11-28
Soil Loss Equation ( USLE ) and Wind Erosion Equation can be used with a reasonable degree of accuracy. It is the intention of ASCS to expand VC/SL to...HD-R37 495 AGRICULTURE’S SOIL CONSERVATION PROGRAMS MISS FULL i/i POTENTIAL IN THE FIGHT.(U) GENERAL ACCOUNTING OFFICE WASHINGTON DC RESOURCES...GENERAL Report To The Congress OF THE UNITED STATES Agriculture’s Soil Conservation Programs Miss Full Potential In The Fight Against Soil Erosion
Built to Last: The Army’s Failed Quest to Replace the Bradley Fighting Vehicle
2015-05-23
Army believes that the BFV does not have the space, weight, or power needed on the modern battlefield. The persistent need for a replacement vehicle...the early 1980’s. The Army has long expressed the need to replace the Bradley Fighting Vehicle ( BFV ) with a new ground combat vehicle. The Bradley...one of the original Big Five, was designed to fight a Cold War threat. Requirements have changed since then but the Army continues to use the BFV
Employee Warriors and the Future of the American Fighting Force
2002-06-01
Employee Warriors and the Future of the American Fighting Force HUGH S. VEST Major, USAF Fairchild Paper Air University Press Maxwell Air Force...control number. 1. REPORT DATE 00 JUN 2002 2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE Employee Warriors and the Future of the...American Fighting Force 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK
Ideology Has No Borders: Why We Need a Containment-Plus Strategy for the Islamic State
2015-04-01
Deft Command of Varied Media 50 Brooking, The U.S. Government Should Pay Anonymous in Bitcoin to Fight ISIS 51 Francis, Why Don Draper Would Be...Government Should Pay Anonymous in Bitcoin to Fight ISIS. Foreign Policy, 3 March 2015. http://foreignpolicy.com/2015/03/03/the-u-s-government-should...pay-anonymous-in- bitcoin -to-fight-isis/ (accessed 7 March 2015). Churchill, Winston. The Sinews of Peace (Iron Curtain Speech). Westminster College
The Impact of the Method of Gunshot Injury: War Injuries vs. Stray Bullets vs. Civilian Fighting.
Mansor, Salah; Bodalal, Zuhir
2015-04-01
To analyze the impact of the method of Gunshot Injury (GSI) (i.e. war injuries, stray bullets, and civilian fighting) on patient morbidity and mortality. An observational study. Biostatistics Department of Al-Jalaa Hospital in Benghazi, Libya, from January to December 2011. Patients' records were analyzed with the method of gunshot injury as a classifying/comparative parameter. Age, gender, site of injury, receiving department, ICU admission, city of origin, length of stay, morbidity and mortality were determined and compared between the different methods of GSI. During the conflict, 1761 gunshot injuries were treated at the hospital. The method of injury was recorded for 62% (n=1096) of the cases and were classified under war injuries (72.2%, n=791), stray bullets (14.1%, n=155), and civilian fighting (13.7%, n=150). Nearly all the patients being treated for civilian fighting (98%, n=147) were males, (stray bullets, 82.6%, n=128, and war injuries 98.4%, n=778). Women were significantly less involved in a war injury (1.6%, n=13, p < 0.001). Stray bullets affected the younger age groups i.e. ² 19 years (26.5%, n=41) more than either fighting injuries (8%, n=12) or war injuries (11.8%, n=93, p < 0.001). Civilian fighting injuries (83.3%, n=125) mostly involved the 20-39 years age group (p < 0.001). Fighting wounds and stray bullets were more common in an urban (82.7%, n=124) rather than rural setting (p < 0.001); the same was true for stray bullets (76.8%, n = 119). The number of GSI's showed a close relationship with major events in society (i.e. military campaigns, celebration and civilian unrest). Significantly higher mortality rates were observed in civilian fighting injuries (7.7%, n=12, p=0.003) and stray bullets (10%, n=15, p=0.003) compared to general GSI's (5.2%, n=91) and war injuries (4.4%, n=35). Surgeons and general physicians need to be aware that GSI's differ in their salient features and outcome based on the method of injury.
Lung, Jrhau; Chen, Kuan-Liang; Hung, Chien-Hui; Chen, Chih-Cheng; Hung, Ming-Szu; Lin, Yu-Ching; Wu, Ching-Yuan; Lee, Kuan-Der; Shih, Neng-Yao; Tsai, Ying Huang
2017-01-01
Unlimited growth of cancer cells requires an extensive nutrient supply. To meet this demand, cancer cells drastically upregulate glucose uptake and metabolism compared to normal cells. This difference has made the blocking of glycolysis a fascinating strategy to treat this malignant disease. α-enolase is not only one of the most upregulated glycolytic enzymes in cancer cells, but also associates with many cellular processes or conditions important to cancer cell survival, such as cell migration, invasion, and hypoxia. Targeting α-enolase could simultaneously disturb cancer cells in multiple ways and, therefore, is a good target for anticancer drug development. In the current study, more than 22 million chemical structures meeting the criteria of Lipinski’s rule of five from the ZINC database were docked to α-enolase by virtual screening. Twenty-four chemical structures with docking scores better than that of the enolase substrate, 2-phosphoglycerate, were further screened by the absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties prediction. Four of them were classified as non-mutagenic, non-carcinogenic, and capable of oral administration where they showed steady interactions to α-enolase that were comparable, even superior, to the currently available inhibitors in molecular dynamics (MD) simulation. These compounds may be considered promising leads for further development of the α-enolase inhibitors and could help fight cancer metabolically. PMID:29180852
Jehu, Deborah A; Lajoie, Yves; Paquet, Nicole
2017-12-21
The purpose of this study was to investigate obstacle clearance and reaction time parameters when crossing a series of six obstacles in older adults. A second aim was to examine the repeated exposure of this testing protocol once per week for 5 weeks. In total, 10 older adults (five females; age: 67.0 ± 6.9 years) walked onto and over six obstacles of varying heights (range: 100-200 mm) while completing no reaction time, simple reaction time, and choice reaction time tasks once per week for 5 weeks. The highest obstacles elicited the lowest toe clearance, and the first three obstacles revealed smaller heel clearance compared with the last three obstacles. Dual tasking negatively impacted obstacle clearance parameters when information processing demands were high. Longer and less consistent time to completion was observed in Session 1 compared with Sessions 2-5. Finally, improvements in simple reaction time were displayed after Session 2, but choice reaction time gradually improved and did not reach a plateau after repeated testing.
Numerical approach of collision avoidance and optimal control on robotic manipulators
NASA Technical Reports Server (NTRS)
Wang, Jyhshing Jack
1990-01-01
Collision-free optimal motion and trajectory planning for robotic manipulators are solved by a method of sequential gradient restoration algorithm. Numerical examples of a two degree-of-freedom (DOF) robotic manipulator are demonstrated to show the excellence of the optimization technique and obstacle avoidance scheme. The obstacle is put on the midway, or even further inward on purpose, of the previous no-obstacle optimal trajectory. For the minimum-time purpose, the trajectory grazes by the obstacle and the minimum-time motion successfully avoids the obstacle. The minimum-time is longer for the obstacle avoidance cases than the one without obstacle. The obstacle avoidance scheme can deal with multiple obstacles in any ellipsoid forms by using artificial potential fields as penalty functions via distance functions. The method is promising in solving collision-free optimal control problems for robotics and can be applied to any DOF robotic manipulators with any performance indices and mobile robots as well. Since this method generates optimum solution based on Pontryagin Extremum Principle, rather than based on assumptions, the results provide a benchmark against which any optimization techniques can be measured.
Exploring performance obstacles of intensive care nurses.
Gurses, Ayse P; Carayon, Pascale
2009-05-01
High nursing workload, poor patient safety, and poor nursing quality of working life (QWL) are major issues in intensive care units (ICUs). Characteristics of the ICU and performance obstacles may contribute to these issues. The goal of this study was to comprehensively identify the performance obstacles perceived by ICU nurses. We used a qualitative research design and conducted semi-structured interviews with 15 ICU nurses of a medical-surgical ICU. Based on this qualitative study and a previously reported quantitative study, we identified seven main types of performance obstacles experienced by ICU nurses. Obstacles related to the physical environment (e.g., noise, amount of space), family relations (e.g., distractions caused by family, lack of time to spend with family), and equipment (e.g., unavailability, misplacement) were the most frequently experienced performance obstacles. The qualitative interview data provided rich information regarding the factors contributing to the performance obstacles. Overall, ICU nurses experience a variety of performance obstacles in their work on a daily basis. Future research is needed to understand the impact of performance obstacles on nursing workload, nursing QWL, and quality and safety of care.
Immunotherapy: How the Immune System Fights Cancer
Immunotherapy uses the body’s immune system to fight cancer. This animation explains three types of immunotherapy used to treat cancer: nonspecific immune stimulation, T-cell transfer therapy, and immune checkpoint inhibitors.
Kumar, Manish; Mohanty, Ajeet Kumar; Sreenivasamurthy, Sreelakshmi K; Dey, Gourav; Advani, Jayshree; Pinto, Sneha M; Kumar, Ashwani; Prasad, Thottethodi Subrahmanya Keshava
2017-09-01
Malaria remains a grand challenge for disruptive innovation in global health therapeutics and diagnostics. Anopheles stephensi is one of the major vectors of malaria in Asia. Vector and transmission control are key focus areas in the fight against malaria, a field of postgenomics research where proteomics can play a substantive role. Moreover, to identify novel strategies to control the vector population, it is necessary to understand the vector life processes at a global and molecular scale. In this context, fat body is a vital organ required for vitellogenesis, vector immunity, vector physiology, and vector-parasite interaction. Given its central role in energy metabolism, vitellogenesis, and immune function, the proteome profile of the fat body and the impact of blood meal (BM) ingestion on the protein abundances of this vital organ have not been investigated so far. Therefore, using a proteomics approach, we identified the proteins expressed in the fat body of An. stephensi and their differential expression in response to BM ingestion. In all, we identified 3,218 proteins in the fat body using high-resolution mass spectrometry, of which 483 were found to be differentially expressed in response to the BM ingestion. Bioinformatics analysis of these proteins underscored their role in amino acid metabolism, vitellogenesis, lipid transport, signal peptide processing, mosquito immunity, and oxidation-reduction processes. Interestingly, we identified five novel genes, which were found to be differentially expressed upon BM ingestion. Proteins that exhibited altered expression in the present study are potential targets for vector control strategies and development of transmission blocking vaccines in the fight against malaria.
Health reform for the 21st century? It may have to wait until the 21st century.
Budetti, P P
1997-01-15
To assess the likelihood of health care legislation in the forthcoming 105th Congress in 5 areas: health care coverage, tax and Employee Retirement Income Security Act (ERISA) policy, Medicaid, Medicare, and managed care. Informal, semistructured conversations that took place in the months prior to the 1996 elections. Congressional health staff and administration officials. Unofficial, off-the-record personal opinions. Health care coverage initiatives to benefit children and unemployed persons are likely to be proposed, but have little chance of enactment; children are seen as well provided for under current Medicaid law, the strong economy and high employment levels lower concern for unemployed issues, and the effort required to pass the Kassebaum-Kennedy legislation needs time to settle. Tax proposals, such as medical savings accounts (MSAs), and ERISA amendments have no constituency; also, the MSA demonstration in Kassebaum-Kennedy will forestall further action. Medicaid is far less an issue than in the previous Congress, because spending has fallen unexpectedly, the bitter fight over block grants makes them unlikely to be revisited, and the administration is likely to enhance state flexibility through waivers. Medicare will be the subject of substantial action to defer impending insolvency temporarily, but there is virtually no chance that definitive long-term solutions will be enacted even though the underlying fiscal problems are thoroughly understood and recognized. Managed care will be the venue for numerous proposals designed to address specific consumer and quality issues. Four bitter years of fighting over health care issues has raised awareness of the problems, but has produced a political chemistry that is too rancorous to permit passage of significant legislation in the near future.
Poolkhet, C; Chairatanayuth, P; Thongratsakul, S; Yatbantoong, N; Kasemsuwan, S; Damchoey, D; Rukkwamsuk, T
2013-09-01
The aim of this study is to explain the social networks of the backyard chicken in Ratchaburi, Suphan Buri and Nakhon Pathom Provinces. In this study, we designed the nodes as groups of persons or places involved in activities relating to backyard chickens. The ties are all activities related to the nodes. The study applied a partial network approach to assess the spreading pattern of avian influenza. From 557 questionnaires collected from the nodes, the researchers found that the degree (the numbers of ties that a node has) and closeness (the distance from one node to the others) centralities of Nakhon Pathom were significantly higher than those of the others (P<0.001). The results show that compared with the remaining areas, this area is more quickly connected to many links. If the avian influenza virus subtype H5N1 was released into the network, the disease would spread throughout this province more rapidly than in Ratchaburi and Suphan Buri. The betweenness centrality in each of these provinces showed no differences (P>0.05). In this study, the nodes that play an important role in all networks are farmers who raise consumable chicken, farmers who raise both consumable chicken and fighting cocks, farmers' households that connect with dominant nodes, and the owners and observers of fighting cocks at arenas and training fields. In this study, we did not find cut points or blocks in the network. Moreover, we detected a random network in all provinces. Thus, connectivity between the nodes covers long or short distances, with less predictable behaviour. Finally, this study suggests that activities between the important nodes must receive special attention for disease control during future disease outbreaks. © 2012 Blackwell Verlag GmbH.
Kim, Hoyeon; Cheang, U. Kei
2017-01-01
In order to broaden the use of microrobots in practical fields, autonomous control algorithms such as obstacle avoidance must be further developed. However, most previous studies of microrobots used manual motion control to navigate past tight spaces and obstacles while very few studies demonstrated the use of autonomous motion. In this paper, we demonstrated a dynamic obstacle avoidance algorithm for bacteria-powered microrobots (BPMs) using electric field in fluidic environments. A BPM consists of an artificial body, which is made of SU-8, and a high dense layer of harnessed bacteria. BPMs can be controlled using externally applied electric fields due to the electrokinetic property of bacteria. For developing dynamic obstacle avoidance for BPMs, a kinematic model of BPMs was utilized to prevent collision and a finite element model was used to characteristic the deformation of an electric field near the obstacle walls. In order to avoid fast moving obstacles, we modified our previously static obstacle avoidance approach using a modified vector field histogram (VFH) method. To validate the advanced algorithm in experiments, magnetically controlled moving obstacles were used to intercept the BPMs as the BPMs move from the initial position to final position. The algorithm was able to successfully guide the BPMs to reach their respective goal positions while avoiding the dynamic obstacles. PMID:29020016
Kim, Hoyeon; Cheang, U Kei; Kim, Min Jun
2017-01-01
In order to broaden the use of microrobots in practical fields, autonomous control algorithms such as obstacle avoidance must be further developed. However, most previous studies of microrobots used manual motion control to navigate past tight spaces and obstacles while very few studies demonstrated the use of autonomous motion. In this paper, we demonstrated a dynamic obstacle avoidance algorithm for bacteria-powered microrobots (BPMs) using electric field in fluidic environments. A BPM consists of an artificial body, which is made of SU-8, and a high dense layer of harnessed bacteria. BPMs can be controlled using externally applied electric fields due to the electrokinetic property of bacteria. For developing dynamic obstacle avoidance for BPMs, a kinematic model of BPMs was utilized to prevent collision and a finite element model was used to characteristic the deformation of an electric field near the obstacle walls. In order to avoid fast moving obstacles, we modified our previously static obstacle avoidance approach using a modified vector field histogram (VFH) method. To validate the advanced algorithm in experiments, magnetically controlled moving obstacles were used to intercept the BPMs as the BPMs move from the initial position to final position. The algorithm was able to successfully guide the BPMs to reach their respective goal positions while avoiding the dynamic obstacles.
78 FR 8345 - American Heart Month, 2013
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-06
... cardiovascular disease, there are also several controllable risk factors, including: blood cholesterol levels... ongoing fight against cardiovascular disease, the Congress, by Joint Resolution approved December 30, 1963... commitment to fighting cardiovascular disease. [[Page 8346
The Fight against the Cigarette Epidemic.
ERIC Educational Resources Information Center
Ginzel, K. H.
1988-01-01
Analyzes progress in the fight against the "cigarette epidemic," presents evidence relating smoking to cancer, and provides suggestions for citizen action to curb cigarette-smoking and to prevent children from developing the habit. (LS)
Fighting Allergies with Research and Information
... Navigation Bar Home Current Issue Past Issues Fighting Allergies with Research and Information Past Issues / Summer 2006 ... Director An interview with Anthony S. Fauci Are seasonal allergies on the rise? If so, why? There has ...
A Relentless Illness—Fighting Diabetes
... in the fight to control and cure type 1 diabetes. As international chairman of the Juvenile Diabetes Research ... advances in the understanding and treatment of type 1 diabetes—even as she has fought to control her ...
The effect of observers on behavior and the brain during aggressive encounters
Desjardins, Julie K.; Becker, Lisa; Fernald, Russell D.
2015-01-01
What effect does an audience have on an animal’s behavior and where is this influence registered in the brain? To answer these questions, we analyzed male cichlid fish fighting in the presence of audiences of various compositions and measured expression of immediate early genes in the brain as a proxy for neural activity. We hypothesized their behavior would change depending on who was watching them. We measured behavioral responses from both the “watchers” and the “watched” during aggressive encounters and found that males fighting in the presence of an audience were more aggressive than males fighting without an audience. Depending on the nature of the audience, immediate early gene expression in key brain nuclei was differentially influenced. Both when an audience of larger males watched fighting males, and when they were watching larger males fighting, nuclei in the brain considered homologous with mammalian nuclei known to be associated with anxiety showed increased activity. When males were in the presence of any audience or when males saw any other males fighting, nuclei in the brain known to be involved in reproduction and aggression were differentially activated relative to control animals. In all cases, there was a close relationship between patterns of brain gene expression between fighters and observers. This suggests that the network of brain regions known as the social behavior network, common across vertebrates, are activated not only in association with the expression of social behavior but also by the reception of social information. PMID:26097004
Injury rates and risk factors in competitive professional boxing.
Zazryn, Tsharni R; McCrory, Paul R; Cameron, Peter A
2009-01-01
To determine injury rates and risk factors for injury in a cohort of professional boxers. Retrospective cohort design reporting on data collected for a fight statistics database maintained by the Professional Boxing and Combat Sports Board of Victoria, Australia. Data were extracted for the years January 1997 through June 2005. Victoria, Australia. 545 professional boxers (age, 18 to 43 years) who participated in a total of 907 fights over the study period. Independent variables under investigation included age, gender, weight, bout exposure, and location of the bout (within or outside of the State of Victoria). Physician-reported acute boxing injuries occurring during bouts of any region or nature. 214 injuries were sustained over the 8.5 years, corresponding to an injury rate of 23.6 per 100 professional fights. The majority of these injuries were lacerations to the head and face. An increasing age and an increasing number of fights were both significant predictors of injury. Injury reduction strategies for professional boxing might include restrictions of eligibility to fight based on age and boxing bout exposure. Future research using prospective cohort designs and standardized injury definitions are needed to confirm these results. Greater mechanistic detail and more complete data entry are necessary to ensure that optimal injury prevention strategies can be developed and implemented. Upon confirmation of the results of this study, the Professional Boxing and Combat Sports Board of Victoria may consider different criteria upon which to sanction a fight.
Neuromuscular Responses to Simulated Brazilian Jiu-Jitsu Fights
da Silva, Bruno Victor Corrêa; Ide, Bernardo Neme; de Moura Simim, Mário Antônio; Marocolo, Moacir; da Mota, Gustavo Ribeiro
2014-01-01
The aim of this study was to investigate the neuromuscular performance responses following successive Brazilian Jiu-Jitsu (BJJ) fights. Twenty-three BJJ athletes (age: 26.3 ± 6.3 years; body mass: 79.4 ± 9.7 kg; body height: 1.80 ± 0.1 m) undertook 3 simulated BJJ fights (10 min duration each separated by 15 min of rest). Neuromuscular performance was measured by the bench press throw (BPT) and vertical counter movement jump (VCMJ) tests, assessed before the 1st fight (Pre) and after the last one (Post). Blood lactate (LA) was measured at Pre, 1 min Post, and 15 min Post fights. Paired t-tests were employed in order to compare the BPT and VCMJ results. One-way ANOVA with Bonferroni post hoc tests were utilized to compare LA responses. The results revealed a significant (p < 0.05) increase in VCMJ performance (40.8 ± 5.5 cm Pre vs. 42.0 ± 5.8 cm Post), but no significant changes in the BPT (814 ± 167 W Pre vs. 835 ± 213 W Post) were observed. LA concentration increased significantly (p < 0.05) at Post, both in the 1st min (10.4 ± 2.7 mmol L-1) and the 15th min (6.4 ± 2.5 mmol L-1) of recovery. We concluded that successive simulated BJJ fights demanded considerable anaerobic contribution of ATP supply, reinforcing the high-intensity intermittent nature of the sport. Nevertheless, no negative impact on acute neuromuscular performance (power) was observed. PMID:25713685
Neuromuscular responses to simulated brazilian jiu-jitsu fights.
da Silva, Bruno Victor Corrêa; Ide, Bernardo Neme; de Moura Simim, Mário Antônio; Marocolo, Moacir; da Mota, Gustavo Ribeiro
2014-12-09
The aim of this study was to investigate the neuromuscular performance responses following successive Brazilian Jiu-Jitsu (BJJ) fights. Twenty-three BJJ athletes (age: 26.3 ± 6.3 years; body mass: 79.4 ± 9.7 kg; body height: 1.80 ± 0.1 m) undertook 3 simulated BJJ fights (10 min duration each separated by 15 min of rest). Neuromuscular performance was measured by the bench press throw (BPT) and vertical counter movement jump (VCMJ) tests, assessed before the 1st fight (Pre) and after the last one (Post). Blood lactate (LA) was measured at Pre, 1 min Post, and 15 min Post fights. Paired t-tests were employed in order to compare the BPT and VCMJ results. One-way ANOVA with Bonferroni post hoc tests were utilized to compare LA responses. The results revealed a significant (p < 0.05) increase in VCMJ performance (40.8 ± 5.5 cm Pre vs. 42.0 ± 5.8 cm Post), but no significant changes in the BPT (814 ± 167 W Pre vs. 835 ± 213 W Post) were observed. LA concentration increased significantly (p < 0.05) at Post, both in the 1st min (10.4 ± 2.7 mmol L-1) and the 15th min (6.4 ± 2.5 mmol L-1) of recovery. We concluded that successive simulated BJJ fights demanded considerable anaerobic contribution of ATP supply, reinforcing the high-intensity intermittent nature of the sport. Nevertheless, no negative impact on acute neuromuscular performance (power) was observed.
Brooks-Russell, Ashley; Wang, Jing; Iannotti, Ronald J.
2014-01-01
Objectives. We examined trends from 1998 to 2010 in bullying, bullying victimization, physical fighting, and weapon carrying and variations by gender, grade level, and race/ethnicity among US adolescents. Methods. The Health Behavior in School-Aged Children surveys of nationally representative samples of students in grades 6 through 10 were completed in 1998 (n = 15 686), 2002 (n = 14 818), 2006 (n = 9229), and 2010 (n = 10 926). We assessed frequency of bullying behaviors, physical fighting, and weapon carrying as well as weapon type and subtypes of bullying. We conducted logistic regression analyses, accounting for the complex sampling design, to identify trends and variations by demographic factors. Results. Bullying perpetration, bullying victimization, and physical fighting declined from 1998 to 2010. Weapon carrying increased for White students only. Declines in bullying perpetration and victimization were greater for boys than for girls. Declines in bullying perpetration and physical fighting were greater for middle-school students than for high-school students. Conclusions. Declines in most violent behaviors are encouraging; however, lack of decline in weapon carrying merits further attention. PMID:24825213
[Predictors of fighting spirit or helplessness/hopelessness in people with cancer].
Oh, Pok-Ja; Lee, Yeon-Joo
2008-04-01
This study was done to identify predictors of the fighting spirit or helplessness/hopelessness in the patients' mental adjustment to cancer. Cancer patients' characteristics like performance status, metastasis and duration of diagnosis with demographic factors, spiritual support and social support were used as predictors of a fighting spirit or helplessness/hopelessness. A total of 124 ambulatory cancer patients completed the Mental Adjustment to Cancer (MAC) scale and responded in a structured instrument about their characteristics, spiritual and social support. The results of multiple regression analysis revealed that confidence in the supporter (R(2)=.114, p=.000), duration of cancer diagnosis (R(2)=.041, p=.000) and faith (R(2)=.030, p=.000) were predictive of a fighting spirit (R(2)=.185, p=.000); whereas, education (R(2)=.074, p=.001), performance status (R(2)=.055, p=.000), satisfaction with social support (R(2)=.046, p=.000), and metastasis (R(2)=.037, p=.000) were predictive of helplessness/hopelessness (R(2)=.202, p=.000). Social support, spiritual support and disease related factors like metastasis, performance status, and duration of cancer diagnosis need to be considered in a psychosocial nursing intervention for a fighting spirit or helplessness/hopelessness.
Tanner, Colby J
2006-11-07
The relationship between numerical advantage and competitive ability is a fundamental component in contests between groups of social animals. An individual's ability to correctly assess the numerical state of its group is of vital importance. In addition to numerical dominance, the group's fighting ability also plays an important role in competitive interactions. By staging experimental fights between two Formica ant species, I show that Formica xerophila are able to assess their own group's strength prior to any competitive encounter. Ants that perceive themselves as part of a large group act more aggressively toward a competitor than ants that perceive themselves as isolated individuals. This increase in aggression improves F. xerophila's competitive ability. Furthermore, the number of individuals in a contest was found to affect competitive ability. In contests with equal number of competitors, groups of F. xerophila were more successful than individual F. xerophila. Contrary to previous predictions using Lanchester's laws of fighting, F. xerophila's ability to kill competitors increased nonlinearly with group size. This nonlinearity was due to the collective fighting strategy of an F. xerophila group isolating and engaging a single Formica integroides competitors.
Tanner, Colby J
2006-01-01
The relationship between numerical advantage and competitive ability is a fundamental component in contests between groups of social animals. An individual's ability to correctly assess the numerical state of its group is of vital importance. In addition to numerical dominance, the group's fighting ability also plays an important role in competitive interactions. By staging experimental fights between two Formica ant species, I show that Formica xerophila are able to assess their own group's strength prior to any competitive encounter. Ants that perceive themselves as part of a large group act more aggressively toward a competitor than ants that perceive themselves as isolated individuals. This increase in aggression improves F. xerophila's competitive ability. Furthermore, the number of individuals in a contest was found to affect competitive ability. In contests with equal number of competitors, groups of F. xerophila were more successful than individual F. xerophila. Contrary to previous predictions using Lanchester's laws of fighting, F. xerophila's ability to kill competitors increased nonlinearly with group size. This nonlinearity was due to the collective fighting strategy of an F. xerophila group isolating and engaging a single Formica integroides competitors. PMID:17015327
Wilmut, K; Barnett, A L
2017-05-01
Obstacles often appear unexpectedly in our pathway and these require us to make adjustments to avoid collision. Previous research has demonstrated that healthy adults will make anticipatory adjustments to gait where they have been told there is the possibility of an obstacle appearing. One population that may find this type of anticipatory movement difficult is individuals with Developmental Coordination Disorder (DCD). The current study considered how individuals with and without DCD adjust to the possibility of an obstacle appearing which would require circumvention. Fortyfour individuals with DCD and 44 age-matched controls (aged from 7 to 34 years of age) walked down an 11 m walkway under three conditions. Initially they were told this was a clear pathway and nothing in the environment would change (1, no possibility of an obstacle, no obstacle). They then performed a series of trials in which a gate may (2, possibility of an obstacle, obstacle) or may not (3, possibility of an obstacle, no obstacle) partially obstruct their pathway. We found that all participants increased medio-lateral trunk acceleration when there was the possibility of an obstacle but before the obstacle appeared, in addition the typical adults and older children also increased step width. When describing circumvention we found that the younger children showed an increase in trunk velocity and acceleration in all three directions compared to older children and adults. We also found that the individuals with DCD adjusted their path sooner and deviated more than their peers. The degree of adjustment to step width in anticipation of an obstacle was related to later medio-lateral velocity and timing of the deviation. Therefore, the lack of 'readying' the system where there is the possibility of an obstacle appearing seen in the individuals with DCD and the younger typical children may explain the increased medio-lateral velocity seen during circumvention.
Sun, Liping; Luo, Yonglong; Ding, Xintao; Zhang, Ji
2014-01-01
An important component of a spatial clustering algorithm is the distance measure between sample points in object space. In this paper, the traditional Euclidean distance measure is replaced with innovative obstacle distance measure for spatial clustering under obstacle constraints. Firstly, we present a path searching algorithm to approximate the obstacle distance between two points for dealing with obstacles and facilitators. Taking obstacle distance as similarity metric, we subsequently propose the artificial immune clustering with obstacle entity (AICOE) algorithm for clustering spatial point data in the presence of obstacles and facilitators. Finally, the paper presents a comparative analysis of AICOE algorithm and the classical clustering algorithms. Our clustering model based on artificial immune system is also applied to the case of public facility location problem in order to establish the practical applicability of our approach. By using the clone selection principle and updating the cluster centers based on the elite antibodies, the AICOE algorithm is able to achieve the global optimum and better clustering effect.
A stereo vision-based obstacle detection system in vehicles
NASA Astrophysics Data System (ADS)
Huh, Kunsoo; Park, Jaehak; Hwang, Junyeon; Hong, Daegun
2008-02-01
Obstacle detection is a crucial issue for driver assistance systems as well as for autonomous vehicle guidance function and it has to be performed with high reliability to avoid any potential collision with the front vehicle. The vision-based obstacle detection systems are regarded promising for this purpose because they require little infrastructure on a highway. However, the feasibility of these systems in passenger car requires accurate and robust sensing performance. In this paper, an obstacle detection system using stereo vision sensors is developed. This system utilizes feature matching, epipoplar constraint and feature aggregation in order to robustly detect the initial corresponding pairs. After the initial detection, the system executes the tracking algorithm for the obstacles. The proposed system can detect a front obstacle, a leading vehicle and a vehicle cutting into the lane. Then, the position parameters of the obstacles and leading vehicles can be obtained. The proposed obstacle detection system is implemented on a passenger car and its performance is verified experimentally.
When Your Parents Fight (For Kids)
... First Aid & Safety Doctors & Hospitals Videos Recipes for Kids Kids site Sitio para niños How the Body ... from a job or other worries. How Do Kids Feel When Their Parents Fight? Kids usually feel ...
Defense.gov - Special Report: Travels with Gates
Mexico City to strengthen the U.S.-Mexico military partnership in the fight against drug cartels there the Mexican government fight drug-trafficking cartels and other security threats. Secretary of State
Obstacle Avoidance On Roadways Using Range Data
NASA Astrophysics Data System (ADS)
Dunlay, R. Terry; Morgenthaler, David G.
1987-02-01
This report describes range data based obstacle avoidance techniques developed for use on an autonomous road-following robot vehicle. The purpose of these techniques is to detect and locate obstacles present in a road environment for navigation of a robot vehicle equipped with an active laser-based range sensor. Techniques are presented for obstacle detection, obstacle location, and coordinate transformations needed in the construction of Scene Models (symbolic structures representing the 3-D obstacle boundaries used by the vehicle's Navigator for path planning). These techniques have been successfully tested on an outdoor robotic vehicle, the Autonomous Land Vehicle (ALV), at speeds up to 3.5 km/hour.
Stepping over obstacles: anticipatory modifications in children with and without Down syndrome.
Virji-Babul, Naznin; Brown, Michelle
2004-12-01
The purpose of this study was to explore the mechanism of anticipatory control of gait in relation to the perception of an obstacle. Typically developing (TD) children (4-7 years of age) and children with Down syndrome (5-6 years of age) walked and stepped over obstacles of two different heights-a "subtle" obstacle that was placed at a very low distance from the floor (1% of total body height) and an "obvious" obstacle that was placed at a much higher distance from the floor (15% of total body height). Spatial and temporal measures of the gait cycle were analyzed. TD children showed increased variability in pre-obstacle step lengths only in response to the higher obstacle. Children with DS showed a decrease in variability in response to the higher obstacle and marked qualitative changes in their gait cycle. Both groups of children were able to scale toe clearance with obstacle height. These results show that TD young children can make task-specific anticipatory adjustments by modulating step length and toe clearance. Children with DS show appropriate scaling of toe clearance and are beginning to show the emergence of anticipatory responses under specific environmental conditions.
Zhang, Wei; Wei, Shilin; Teng, Yanbin; Zhang, Jianku; Wang, Xiufang; Yan, Zheping
2017-01-01
In view of a dynamic obstacle environment with motion uncertainty, we present a dynamic collision avoidance method based on the collision risk assessment and improved velocity obstacle method. First, through the fusion optimization of forward-looking sonar data, the redundancy of the data is reduced and the position, size and velocity information of the obstacles are obtained, which can provide an accurate decision-making basis for next-step collision avoidance. Second, according to minimum meeting time and the minimum distance between the obstacle and unmanned underwater vehicle (UUV), this paper establishes the collision risk assessment model, and screens key obstacles to avoid collision. Finally, the optimization objective function is established based on the improved velocity obstacle method, and a UUV motion characteristic is used to calculate the reachable velocity sets. The optimal collision speed of UUV is searched in velocity space. The corresponding heading and speed commands are calculated, and outputted to the motion control module. The above is the complete dynamic obstacle avoidance process. The simulation results show that the proposed method can obtain a better collision avoidance effect in the dynamic environment, and has good adaptability to the unknown dynamic environment. PMID:29186878
Gill, Simone V; Hung, Ya-Ching
2014-01-01
Little is known about how obesity relates to motor planning and skills during functional tasks. We collected 3-D kinematics and kinetics as normal weight (n=10) and overweight/obese (n=12) children walked on flat ground and as they crossed low, medium, and high obstacles. We investigated if motor planning and motor skill impairments were evident during obstacle crossing. Baseline conditions showed no group differences (all ps>.05). Increased toe clearance was found on low obstacles (p=.01) for the overweight/obese group and on high obstacles (p=.01) for the normal weight group. With the crossing leg, the overweight/obese group had larger hip abduction angles (p=.01) and medial ground reaction forces (p=.006) on high obstacles and high anterior ground reaction forces on low obstacles (p=.001). With the trailing leg, overweight/obese children had higher vertical ground reaction forces on high obstacles (p=.005) and higher knee angles (p=.01) and anterior acceleration in the center of mass (p=.01) on low obstacles. These findings suggest that differences in motor planning and skills in overweight/obese children may be more apparent during functional activities. Copyright © 2013 Elsevier Ltd. All rights reserved.
Shock interaction behind a pair of cylindrical obstacles
NASA Astrophysics Data System (ADS)
Liu, Heng; Mazumdar, Raoul; Eliasson, Veronica
2014-11-01
The body of work focuses on two-dimensional numerical simulations of shock interaction with a pair of cylindrical obstacles, varying the obstacle separation and incident shock strength. With the shock waves propagating parallel to the center-line between the two cylindrical obstacles, the shock strengths simulated vary from a Mach of 1.4 to a Mach of 2.4, against a wide range of obstacle separation distance to their diameters. These cases are simulated via a software package called Overture, which is used to solve the inviscid Euler equations of gas dynamics on overlapping grids with adaptive mesh refinement. The goal of these cases is to find a so-called ``safe'' region for obstacle spacing and varying shock Mach numbers, such that the pressure in the ``safe'' region is reduced downstream of the obstacles. The benefits apply to both building and armor design for the purpose of shock wave mitigation to keep humans and equipment safe. The results obtained from the simulations confirm that the length of the ``safe'' region and the degree of shock wave attenuation depend on the ratio of obstacle separation distance to obstacle diameter. The influence of various Mach number is also discussed.
2013-09-01
Infantry Fighting Vehicle (Bradley M2A3 ) – The Bradley fighting vehicle is designed for the mobility; it also protects infantry troops when...Persistence Latency of Info Endurance Outgoing Communication Links Sensors Detection Infantry Soldiers X X Bradley Infantry Soldiers X X Bradley M2A3 X...IndustryAdvisoryGroupIAG/Documents/OUSDI%20DCGS%20IAG%20Kick- off%20Presentation%206–23–09.pdf Military Analysis Network. M2A3 and M3A3 Bradley Fighting
Bai, Jie; Wang, Rui-Hui; Qiao, Yan; Wang, Aidong; Fang, Chen-Jie
2017-01-01
Multidrug resistance (MDR) is a huge obstacle in cancer chemotherapeutics. Overcoming MDR is a great challenge for anticancer drug discovery. Here, DNA binding and cytotoxicity of Schiff base L1 and L2 were explored to assess their efficiency in fighting cancer and overcoming the MDR. L1 and L2 could treat extremely chemoresistant MCF-7/ADR cell as drug-sensitive cell, with drug resistance index (DRI) <2.13, showing high potential in overcoming the MDR. The apoptotic ratio induced by L1 and L2 was low for both MCF-7 and MCF-7/ADR cells. L1 and L2 induced an impairment of cell cycle progression of MCF-7 and MCF-7/ADR cell lines and suppressed cell growth by perturbing progress through the G0/G1 phase, with L2 causing more profound effect, which might account for lower drug resistance after L2 treatment. The molecular docking revealed weak interaction between L1/L2 and P-glycoprotein (P-gp), the most important drug efflux pump and intracellular Rhodamine 123 accumulation indicated that the activity of P-gp was not inhibited by L1 and L2. Combined with the cellular uptake results, it implied that L1 and L2 could bypass P-gp efflux to exert anticancer activity.
Counterfeit drugs: analytical techniques for their identification.
Martino, R; Malet-Martino, M; Gilard, V; Balayssac, S
2010-09-01
In recent years, the number of counterfeit drugs has increased dramatically, including not only "lifestyle" products but also vital medicines. Besides the threat to public health, the financial and reputational damage to pharmaceutical companies is substantial. The lack of robust information on the prevalence of fake drugs is an obstacle in the fight against drug counterfeiting. It is generally accepted that approximately 10% of drugs worldwide could be counterfeit, but it is also well known that this number covers very different situations depending on the country, the places where the drugs are purchased, and the definition of what constitutes a counterfeit drug. The chemical analysis of drugs suspected to be fake is a crucial step as counterfeiters are becoming increasingly sophisticated, rendering visual inspection insufficient to distinguish the genuine products from the counterfeit ones. This article critically reviews the recent analytical methods employed to control the quality of drug formulations, using as an example artemisinin derivatives, medicines particularly targeted by counterfeiters. Indeed, a broad panel of techniques have been reported for their analysis, ranging from simple and cheap in-field ones (colorimetry and thin-layer chromatography) to more advanced laboratory methods (mass spectrometry, nuclear magnetic resonance, and vibrational spectroscopies) through chromatographic methods, which remain the most widely used. The conclusion section of the article highlights the questions to be posed before selecting the most appropriate analytical approach.
Nentwich, M M; Klauss, V; Wilhelm, F
2015-05-01
The shortage of ophthalmologists is a major obstacle in the struggle of fighting preventable blindness in sub-Saharan Africa. However, to date reasons affecting migration of ophthalmologists have not been completely understood. Evaluation of reasons reported by ophthalmologists for staying in their current work setting/country, of potential reasons for migration as well as of effects of German-African partnerships. In the years 2009-2011 and 2013 participants of continuous medical education courses in Ethiopia, Cameroon and Kenya were interviewed using a standardized questionnaire. A total of 106 ophthalmologists participated in this survey. In the years 2009/2010 participants were mainly board certified ophthalmologists, while the 2011/2013 surveys were answered mainly by residents. The main reasons for staying in their current region/country were good working conditions, commitment to help/patriotism, possibility of further training, good income and familial ties. Professional development elsewhere and better income abroad were named as the main reasons for considering migration followed by better technical equipment elsewhere and insecurity in the home country. Good working conditions and the possibility of further training were named as the top reasons for staying in the current region/country apart from commitment to help and familial ties. Therefore, international cooperation programs aiming at improving training of ophthalmologists and establishing an ophthalmic infrastructure may have a role in promoting ophthalmic care in Africa.
Berry, Hugues; Chaté, Hugues
2014-02-01
In vivo measurements of the passive movements of biomolecules or vesicles in cells consistently report "anomalous diffusion," where mean-squared displacements scale as a power law of time with exponent α<1 (subdiffusion). While the detailed mechanisms causing such behaviors are not always elucidated, movement hindrance by obstacles is often invoked. However, our understanding of how hindered diffusion leads to subdiffusion is based on diffusion amidst randomly located immobile obstacles. Here, we have used Monte Carlo simulations to investigate transient subdiffusion due to mobile obstacles with various modes of mobility. Our simulations confirm that the anomalous regimes rapidly disappear when the obstacles move by Brownian motion. By contrast, mobile obstacles with more confined displacements, e.g., Orstein-Ulhenbeck motion, are shown to preserve subdiffusive regimes. The mean-squared displacement of tracked protein displays convincing power laws with anomalous exponent α that varies with the density of Orstein-Ulhenbeck (OU) obstacles or the relaxation time scale of the OU process. In particular, some of the values we observed are significantly below the universal value predicted for immobile obstacles in two dimensions. Therefore, our results show that subdiffusion due to mobile obstacles with OU type of motion may account for the large variation range exhibited by experimental measurements in living cells and may explain that some experimental estimates are below the universal value predicted for immobile obstacles.
Daniele, Gianlorenzo; Weinstein, Richard N; Wallace, Paul Wesley; Palmieri, Vincenzo; Bianco, Massimiliano
2016-11-01
Boxing is a sport where athletes compete in several weight categories. Professional boxers typically dehydrate to cut their weight for the weigh-in (24 h before the contest) and then rehydrate before the fight. The International Boxing Federation (IBF) mandates a second weigh-in 12 h before the fight. Our objectives were: 1) To quantify the weight gain (WG) from the 1st to the 2nd weigh-in; 2) to investigate whether rapid WG affects boxing performance (win/loss rate) and 3) whether weight discrepancy (WD) 15 between boxers exposes them to increased health risks (rate of fights ended before time limit). From official weigh-in reports of 71 IBF fights (142 fighters) the following data were gathered/calculated for each boxer: age, weight division, 1st weight, 2nd weight, WG between weigh-ins (kg and %), WD between opponents, and fight decision. Between the weigh-ins, the average WG was 2.52 ± 1.37 kg (range -0.3/6.4 kg) and 3.8 ± 2.2% of the initial body weight (range -0.4/9.3%) and the average WD 1.94 ± 1.50 kg (maximum 7.10 kg). Both WG and WD did not affect match outcomes. We observed tendencies for higher loss rate among boxers gaining more weight, and for higher victory rate in boxers with larger WD, however without reaching significance. A significant negative correlation was found between the 1st weight and the WG, both in absolute (r = -0.278, p = 0.001) and relative value (r = -0.497, p < 0.0001). Although correlations between WG, WD and boxing performance were not found, single cases with an alarming high WG and WD were noted.
Physiological and Technical-tactical Analysis in Brazilian Jiu-jitsu Competition
Andreato, Leonardo V.; Franchini, Emerson; de Moraes, Solange M.F.; Pastório, Juliana J.; da Silva, Danilo F.; Esteves, João V.D.C; Branco, Braulio H.M.; Romero, Paulo V.dS.; Machado, Fabiana A.
2013-01-01
Purpose The present study aims at investigating the physiological response and technical-tactical parameters in Brazilian jiu-jitsu competition. Methods The study included 35 male Brazilian jiu-jitsu athletes (adult category, body mass: 80.2 ± 13.0 kg), graded from white to brown belt, during combats fought at regional level. Twenty-two fights were analyzed in terms of technique and time structure. Blood glucose, lactate and maximal isometric grip strength were determined before and after the fights. The rate of perceived exertion was also assessed after the fight, using the 6-20 Borg rating. The fights were recorded and the following variables were determined: the exertion/pause ratio and subjective intensity of actions, categorized between low and high intensity. Results The results indicated that during Brazilian jiu-jitsu fights, the glycolytic pathway is only moderately activated (lactate before: 4.4 (4.0 – 4.6) mmol/L, after: 10.1 (8.0 – 11.3) mmol/L; glucose before: 112.4 ± 22.3 mg/dL, after: 130.5 ± 31.0 mg/dL). The exertion during the fight resulted in significant reductions in handgrip strength (right hand grip before: 45.9 ± 10.3 kgf, after: 40.1 ± 9.5 kgf; left hand grip before: 44.2 ± 11.1 kgf, after: 37.0 ± 10.2 kgf). The athletes rated the fight as hard: 15 (13 – 15). Effort/pause ratio was 6:1, while high-intensity actions lasted approximately 4 s, resulting in a low/high intensity? ratio of 8:1. Conclusion It is recommended that coaches direct the training loads to simulate the energy demand imposed by the competitive matches, activating moderately the glycolytic pathway. Moreover, the time structure of combats can be used to prescribe both physical and technical-tactical training. PMID:23802056
Why You Can't Have a Snowball Fight on Mars
NASA Astrophysics Data System (ADS)
Sandford, Scott A.
1998-01-01
Icy worlds such as Mars and outer-planet satellites might seem like winter wonderlands, ideal sites for ski slopes, skating rinks, and the crude pleasures of snowball fights. Alas, it was not meant to be.
Efficiencies from Applying a Rotational Equipping Strategy
2011-01-01
Washington, D.C.: United States Government Accountability Office, 2007. NOTES: BFV = Bradley Fighting Vehicle, HEMTT = heavy expanded mobility tactical...of Its Equipment Reset Strategy, Washington, D.C.: United States Government Accountability Office, 2007. NOTES: BFV = Bradley Fighting Vehicle
ERIC Educational Resources Information Center
Rodman, Peter W.
In developing countries, public administration is hampered by a number of obstacles foreign to large industrialized nations. Some of these obstacles are shortages of tools and skilled personnel, outmoded organizational structures, political competition, and cultural and attitudinal barriers. The administrative obstacles and their…
1989-01-01
This Uruguayan Decree sets forth regulations on the prevention and fighting of forest fires. Among other things, it does the following: 1) requires all public and private organizations, as well as all persons, to assist personally in and provide vehicles, machines, and tools for the fighting of forest fires; 2) requires the owners of property containing forests to maintain instruction in fighting fires for an adequate number of employees; 3) requires all forests to be kept cleared of vegetation capable of spreading fires and to have fire walls; 4) requires owners of forests larger than 30 hectares in size to present to the Forest Directorate an annual plan for forest fire defense; and 5) requires owners of forests larger than 30 hectares in size to maintain specified equipment for fighting fires. Persons violating the provisions of this Decree are subject to fines.
A WebGIS-based command control system for forest fire fighting
NASA Astrophysics Data System (ADS)
Yang, Jianyu; Ming, Dongping; Zhang, Xiaodong; Huang, Haitao
2006-10-01
Forest is a finite resource and fire prevention is crucial work. However, once a forest fire or accident occurs, timely and effective fire-fighting is the only necessary measure. The aim of this research is to build a computerized command control system based on WEBGIS to direct fire-fighting. Firstly, this paper introduces the total technique flow and functional modules of the system. Secondly, this paper analyses the key techniques for building the system, and they are data obtaining, data organizing & management, architecture of WebGIS and sharing & interoperation technique. In the end, this paper demonstrates the on line martial symbol editing function to show the running result of system. The practical application of this system showed that it played very important role in the forest fire fighting work. In addition, this paper proposes some strategic recommendations for the further development of the system.
Chabris, Christopher F; Weinberger, Adam; Fontaine, Matthew; Simons, Daniel J
2011-01-01
Inattentional blindness-the failure to see visible and otherwise salient events when one is paying attention to something else-has been proposed as an explanation for various real-world events. In one such event, a Boston police officer chasing a suspect ran past a brutal assault and was prosecuted for perjury when he claimed not to have seen it. However, there have been no experimental studies of inattentional blindness in real-world conditions. We simulated the Boston incident by having subjects run after a confederate along a route near which three other confederates staged a fight. At night only 35% of subjects noticed the fight; during the day 56% noticed. We manipulated the attentional load on the subjects and found that increasing the load significantly decreased noticing. These results provide evidence that inattentional blindness can occur during real-world situations, including the Boston case.
Intrasexual competition enhances reproductive isolation between locally adapted populations
Arias-Rodriguez, Lenin; Plath, Martin
2018-01-01
Abstract During adaptation to different habitat types, both morphological and behavioral traits can undergo divergent selection. Males often fight for status in dominance hierarchies and rank positions predict reproductive success. Ecotypes with reduced fighting abilities should have low reproductive success when migrating into habitats that harbor ecotypes with superior fighting abilities. Livebearing fishes in the Poecilia mexicana-species complex inhabit not only regular freshwater environments, but also independently colonized sulfidic (H2S-containing) habitats in three river drainages. In the current study, we found fighting intensities in staged contests to be considerably lower in some but not all sulfidic surface ecotypes and the sulfidic cave ecotype compared with populations from non-sulfidic surface sites. This is perhaps due to selection imposed by H2S, which hampers oxygen uptake and transport, as well as cellular respiration. Furthermore, migrants from sulfidic habitats may lose fights even if they do not show overall reduced aggressiveness, as physiological performance is likely to be challenged in the non-sulfidic environment to which they are not adapted. To test this hypothesis, we simulated migration of H2S-adapted males into H2S-free waters, as well as H2S-adapted cave-dwelling males into sulfidic surface waters. We found that intruders established dominance less often than resident males, independent of whether or not they showed reduced aggressiveness overall. Our study shows that divergent evolution of male aggressive behavior may also contribute to the maintenance of genetic differentiation in this system and we call for more careful evaluation of male fighting abilities in studies on ecological speciation. PMID:29492045
The effect of observers on behavior and the brain during aggressive encounters.
Desjardins, Julie K; Becker, Lisa; Fernald, Russell D
2015-10-01
What effect does an audience have on an animal's behavior and where is this influence registered in the brain? To answer these questions, we analyzed male cichlid fish fighting in the presence of audiences of various compositions and measured expression of immediate early genes in the brain as a proxy for neural activity. We hypothesized their behavior would change depending on who was watching them. We measured behavioral responses from both the "watchers" and the "watched" during aggressive encounters and found that males fighting in the presence of an audience were more aggressive than males fighting without an audience. Depending on the nature of the audience, immediate early gene expression in key brain nuclei was differentially influenced. Both when an audience of larger males watched fighting males, and when they were watching larger males fighting, nuclei in the brain considered homologous with mammalian nuclei known to be associated with anxiety showed increased activity. When males were in the presence of any audience or when males saw any other males fighting, nuclei in the brain known to be involved in reproduction and aggression were differentially activated relative to control animals. In all cases, there was a close relationship between patterns of brain gene expression between fighters and observers. This suggests that the network of brain regions known as the social behavior network, common across vertebrates, are activated not only in association with the expression of social behavior but also by the reception of social information. Copyright © 2015 Elsevier B.V. All rights reserved.
Biodegradability of fluorinated fire-fighting foams in water.
Bourgeois, A; Bergendahl, J; Rangwala, A
2015-07-01
Fluorinated fire-fighting foams may be released into the environment during fire-fighting activities, raising concerns due to the potential environmental and health impacts for some fluorinated organics. The current study investigated (1) the biodegradability of three fluorinated fire-fighting foams, and (2) the applicability of current standard measures used to assess biodegradability of fluorinated fire-fighting foams. The biodegradability of three fluorinated fire-fighting foams was evaluated using a 28-day dissolved organic carbon (DOC) Die-Away Test. It was found that all three materials, diluted in water, achieved 77-96% biodegradability, meeting the criteria for "ready biodegradability". Defluorination of the fluorinated organics in the foam during biodegradation was measured using ion chromatography. It was found that the fluorine liberated was 1-2 orders of magnitude less than the estimated initial amount, indicating incomplete degradation of fluorinated organics, and incomplete CF bond breakage. Published biodegradability data may utilize biochemical oxygen demand (BOD), chemical oxygen demand (COD), and total organic carbon (TOC) metrics to quantify organics. COD and TOC of four fluorinated compounds were measured and compared to the calculated carbon content or theoretical oxygen demand. It was found that the standard dichromate-based COD test did not provide an accurate measure of fluorinated organic content. Thus published biodegradability data using COD for fluorinated organics quantification must be critically evaluated for validity. The TOC measurements correlated to an average of 91% of carbon content for the four fluorinated test substances, and TOC is recommended for use as an analytical parameter in fluorinated organics biodegradability tests. Copyright © 2015 Elsevier Ltd. All rights reserved.
Tracked robot controllers for climbing obstacles autonomously
NASA Astrophysics Data System (ADS)
Vincent, Isabelle
2009-05-01
Research in mobile robot navigation has demonstrated some success in navigating flat indoor environments while avoiding obstacles. However, the challenge of analyzing complex environments to climb obstacles autonomously has had very little success due to the complexity of the task. Unmanned ground vehicles currently exhibit simple autonomous behaviours compared to the human ability to move in the world. This paper presents the control algorithms designed for a tracked mobile robot to autonomously climb obstacles by varying its tracks configuration. Two control algorithms are proposed to solve the autonomous locomotion problem for climbing obstacles. First, a reactive controller evaluates the appropriate geometric configuration based on terrain and vehicle geometric considerations. Then, a reinforcement learning algorithm finds alternative solutions when the reactive controller gets stuck while climbing an obstacle. The methodology combines reactivity to learning. The controllers have been demonstrated in box and stair climbing simulations. The experiments illustrate the effectiveness of the proposed approach for crossing obstacles.
The evolution of cooperative turn-taking in animal conflict
2011-01-01
Background A fundamental assumption in animal socio-ecology is that animals compete over limited resources. This view has been challenged by the finding that individuals might cooperatively partition resources by "taking turns". Turn-taking occurs when two individuals coordinate their agonistic behaviour in a way that leads to an alternating pattern in who obtains a resource without engaging in costly fights. Cooperative turn-taking has been largely ignored in models of animal conflict and socio-ecological models that explain the evolution of social behaviours based only on contest and scramble competition. Currently it is unclear whether turn-taking should be included in socio-ecological models because the evolution of turn-taking is not well understood. In particular, it is unknown whether turn-taking can evolve when fighting costs and assessment of fighting abilities are not fixed but emerge from evolved within-fight behaviour. We address this problem with an evolutionary agent-based model. Results We found that turn-taking evolves for small resource values, alongside a contest strategy that leads to stable dominance relationships. Turn-taking leads to egalitarian societies with unclear dominance relationships and non-linear dominance hierarchies. Evolutionary stability of turn-taking emerged despite strength differences among individuals and the possibility to evolve within-fight behaviour that allows good assessment of fighting abilities. Evolutionary stability emerged from frequency-dependent effects on fitness, which are modulated by feedbacks between the evolution of within-fight behaviour and the evolution of higher-level conflict strategies. Conclusions Our results reveal the impact of feedbacks between the evolution of within-fight behaviour and the evolution of higher-level conflict strategies, such as turn-taking. Similar feedbacks might be important for the evolution of other conflict strategies such as winner-loser effects or coalitions. However, we are not aware of any study that investigated such feedbacks. Furthermore, our model suggests that turn-taking could be used by animals to partition low value resources, but to our knowledge this has never been tested. The existence of turn-taking might have been overlooked because it leads to societies with similar characteristics that have been expected to emerge from scramble competition. Analyses of temporal interaction patterns could be used to test whether turn-taking occurs in animals. PMID:22054254
The evolution of cooperative turn-taking in animal conflict.
Franz, Mathias; van der Post, Daniel; Schülke, Oliver; Ostner, Julia
2011-11-03
A fundamental assumption in animal socio-ecology is that animals compete over limited resources. This view has been challenged by the finding that individuals might cooperatively partition resources by "taking turns". Turn-taking occurs when two individuals coordinate their agonistic behaviour in a way that leads to an alternating pattern in who obtains a resource without engaging in costly fights. Cooperative turn-taking has been largely ignored in models of animal conflict and socio-ecological models that explain the evolution of social behaviours based only on contest and scramble competition. Currently it is unclear whether turn-taking should be included in socio-ecological models because the evolution of turn-taking is not well understood. In particular, it is unknown whether turn-taking can evolve when fighting costs and assessment of fighting abilities are not fixed but emerge from evolved within-fight behaviour. We address this problem with an evolutionary agent-based model. We found that turn-taking evolves for small resource values, alongside a contest strategy that leads to stable dominance relationships. Turn-taking leads to egalitarian societies with unclear dominance relationships and non-linear dominance hierarchies. Evolutionary stability of turn-taking emerged despite strength differences among individuals and the possibility to evolve within-fight behaviour that allows good assessment of fighting abilities. Evolutionary stability emerged from frequency-dependent effects on fitness, which are modulated by feedbacks between the evolution of within-fight behaviour and the evolution of higher-level conflict strategies. Our results reveal the impact of feedbacks between the evolution of within-fight behaviour and the evolution of higher-level conflict strategies, such as turn-taking. Similar feedbacks might be important for the evolution of other conflict strategies such as winner-loser effects or coalitions. However, we are not aware of any study that investigated such feedbacks. Furthermore, our model suggests that turn-taking could be used by animals to partition low value resources, but to our knowledge this has never been tested. The existence of turn-taking might have been overlooked because it leads to societies with similar characteristics that have been expected to emerge from scramble competition. Analyses of temporal interaction patterns could be used to test whether turn-taking occurs in animals.
Challenges in Learning to Speak Arabic
ERIC Educational Resources Information Center
Haron, Sueraya Che; Ahmed, Ismaiel Hassanien; Mamat, Arifin; Ahmad, Wan Rusli Wan; Rawash, Fouad Mahmoud M.
2016-01-01
This paper describes a study to investigate the challenges and obstacles to speaking Arabic faced by good and poor Malay speakers of Arabic. The study used individual and focus group interviews with 14 participants to elicit data. The findings revealed 2 types of obstacles, namely, internal and external obstacles. Internal obstacles refer to the…
Women's orgasm obstacles: A qualitative study.
Nekoolaltak, Maryam; Keshavarz, Zohreh; Simbar, Masoumeh; Nazari, Ali Mohammad; Baghestani, Ahmad Reza
2017-08-01
Woman's orgasm plays a vital role in sexual compatibility and marital satisfaction. Orgasm in women is a learnable phenomenon that is influenced by several factors. The aim of this study is exploring obstacles to orgasm in Iranian married women. This qualitative study with directed content analysis approach was conducted in 2015-2016, on 20 Iranian married women who were individually interviewed at two medical clinics in Tehran, Iran. Orgasm obstacles were explored in one category, 4 subcategories, and 25 codes. The main category was "Multidimensionality of women's orgasm obstacles". Subcategories and some codes included: Physical obstacles (wife's or husband's boredom, vaginal infection, insufficient vaginal lubrication), psychological obstacles (lack of sexual knowledge, shame, lack of concentration on sex due to household and children problems), relational obstacles (husband's hurry, having a dispute and annoyance with spouse) and contextual obstacles (Irregular sleep hours, lack of privacy and inability to separate children's bedroom from their parents, lack of peace at home). For prevention or treatment of female orgasm disorders, attention to physical factors is not enough. Obtaining a comprehensive history about physical, psychological, relational and contextual dimensions of woman's life is necessary.
Stochastic performance modeling and evaluation of obstacle detectability with imaging range sensors
NASA Technical Reports Server (NTRS)
Matthies, Larry; Grandjean, Pierrick
1993-01-01
Statistical modeling and evaluation of the performance of obstacle detection systems for Unmanned Ground Vehicles (UGVs) is essential for the design, evaluation, and comparison of sensor systems. In this report, we address this issue for imaging range sensors by dividing the evaluation problem into two levels: quality of the range data itself and quality of the obstacle detection algorithms applied to the range data. We review existing models of the quality of range data from stereo vision and AM-CW LADAR, then use these to derive a new model for the quality of a simple obstacle detection algorithm. This model predicts the probability of detecting obstacles and the probability of false alarms, as a function of the size and distance of the obstacle, the resolution of the sensor, and the level of noise in the range data. We evaluate these models experimentally using range data from stereo image pairs of a gravel road with known obstacles at several distances. The results show that the approach is a promising tool for predicting and evaluating the performance of obstacle detection with imaging range sensors.
Biologically-inspired adaptive obstacle negotiation behavior of hexapod robots
Goldschmidt, Dennis; Wörgötter, Florentin; Manoonpong, Poramate
2014-01-01
Neurobiological studies have shown that insects are able to adapt leg movements and posture for obstacle negotiation in changing environments. Moreover, the distance to an obstacle where an insect begins to climb is found to be a major parameter for successful obstacle negotiation. Inspired by these findings, we present an adaptive neural control mechanism for obstacle negotiation behavior in hexapod robots. It combines locomotion control, backbone joint control, local leg reflexes, and neural learning. While the first three components generate locomotion including walking and climbing, the neural learning mechanism allows the robot to adapt its behavior for obstacle negotiation with respect to changing conditions, e.g., variable obstacle heights and different walking gaits. By successfully learning the association of an early, predictive signal (conditioned stimulus, CS) and a late, reflex signal (unconditioned stimulus, UCS), both provided by ultrasonic sensors at the front of the robot, the robot can autonomously find an appropriate distance from an obstacle to initiate climbing. The adaptive neural control was developed and tested first on a physical robot simulation, and was then successfully transferred to a real hexapod robot, called AMOS II. The results show that the robot can efficiently negotiate obstacles with a height up to 85% of the robot's leg length in simulation and 75% in a real environment. PMID:24523694
Kim, Aram; Kretch, Kari S; Zhou, Zixuan; Finley, James M
2018-05-09
Successful negotiation of obstacles during walking relies on the integration of visual information about the environment with ongoing locomotor commands. When information about the body and environment are removed through occlusion of the lower visual field, individuals increase downward head pitch angle, reduce foot placement precision, and increase safety margins during crossing. However, whether these effects are mediated by loss of visual information about the lower extremities, the obstacle, or both remains to be seen. Here, we used a fully immersive, virtual obstacle negotiation task to investigate how visual information about the lower extremities is integrated with information about the environment to facilitate skillful obstacle negotiation. Participants stepped over virtual obstacles while walking on a treadmill with one of three types of visual feedback about the lower extremities: no feedback, end-point feedback, or a link-segment model. We found that absence of visual information about the lower extremities led to an increase in the variability of leading foot placement after crossing. The presence of a visual representation of the lower extremities promoted greater downward head pitch angle during the approach to and subsequent crossing of an obstacle. In addition, having greater downward head pitch was associated with closer placement of the trailing foot to the obstacle, further placement of the leading foot after the obstacle, and higher trailing foot clearance. These results demonstrate that the fidelity of visual information about the lower extremities influences both feed-forward and feedback aspects of visuomotor coordination during obstacle negotiation.
Taheri, Safoura; Ehsanpour, Soheila; Kohan, Shahnaz
2014-03-01
Organizational and structural obstacles are a group of major obstacles in achievement of appropriate family planning counseling. Detection of these obstacles from the viewpoint of managers, staffs and clients who are key members in health services providing system is a major step toward appropriate planning to modify or delete this group of obstacles. The present study was conducted with the goal of comparing managers', staffs' and clients' viewpoints about organizational and structural obstacles in family planning counseling in health-care centers in Isfahan in 2012. This is a cross-sectional one-step three-group comparative descriptive study conducted on 295 subjects including 59 managers, 110 staffs and 126 clients in medical health-care centers in Isfahan in 2012. Managers and the staffs were selected by census sampling and the clients were recruited through convenient random sampling. The date collection tool was a researcher made questionnaire, which was designed in two sections of fertility and personal characteristics and viewpoint measurement. Descriptive and inferential statistical test were used to analyze the data. The obtained results showed no significant difference between mean scores of viewpoints in three groups of managers, staffs and clients concerning organizational and structural obstacles in family planning counseling (P = 0.677). In addition, most of the managers, staffs and clients reported organizational and structural obstacles as the obstacles in the process of family planning in moderate level. The results showed the necessity of health services managers' planning to modify or delete organizational and structural obstacles especially the agreed obstacles from the viewpoint of managers, staffs and clients.
Obstacle avoidance locomotor tasks: adaptation, memory and skill transfer.
Kloter, Evelyne; Dietz, Volker
2012-05-01
The aim of this study was to explore the neural basis of adaptation, memory and skill transfer during human stepping over obstacles. Whilst walking on a treadmill, subjects had to perform uni- and bilateral obstacle steps. Acoustic feedback information about foot clearance was provided. Non-noxious electrical stimuli were applied to the right tibial nerve during the mid-stance phase of the right leg, i.e. 'prior' to the right or 'during' the left leg swing over the obstacle. The electromyogram (EMG) responses evoked by these stimuli in arm and leg muscles are known to reflect the neural coordination during normal and obstacle steps. The leading and trailing legs rapidly adapted foot clearance during obstacle steps with small further changes when the same obstacle condition was repeated. This adaptation was associated with a corresponding decrease in arm and leg muscle reflex EMG responses. Arm (but not leg) muscle EMG responses were greater when the stimulus was applied 'during' obstacle crossing by the left leg leading compared with stimulation 'prior' to right leg swing over the obstacle. A corresponding difference existed in arm muscle background EMG. The results indicate that, firstly, the somatosensory information gained by the performance and adaptation of uni- and bilateral obstacle stepping becomes transferred to the trailing leg in a context-specific manner. Secondly, EMG activity in arm and leg muscles parallels biomechanical adaptation of foot clearance. Thirdly, a consistently high EMG activity in the arm muscles during swing over the obstacle is required for equilibrium control. Thus, such a precision locomotor task is achieved by a context-specific, coordinated activation of arm and leg muscles for performance and equilibrium control that includes adaptation, memory and skill transfer. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.
[Medical students' smoking habits and attitudes about cessation].
Rinfel, József; Oberling, János; Tóth, Ildikó; Prugberger, László; Nagy, Lajos
2011-03-20
Medical years are very important in shaping the attitudes of future doctors. It is proven that doctors who smoke do not advise their patient to stop smoking. We have to know the students' smoking habits and attitudes about smoking cessation to make them interested in the fight against tobacco. To investigate medical students' smoking habits and attitudes about cessation. We applied the Hungarian translation of the Global Health Professionals Student Survey. Medical students from the first and fifth year filled in the survey anonymously during the seminars. Statistical analysis was performed with SPSS. In both years 245 students filled in the questionnaire. In the first year 30.8%, in the fifth year 38.9% of the students were defined as smokers. During the academic study the number of daily smokers and the number of smoked cigarettes increases. Students require training about smoking cessation, however they would entrust it to a specialist. Based on our data we need a teaching block in the curricula about smoking and smoking cessation.
Coinhibitory molecules in cancer biology and therapy.
Mocellin, Simone; Benna, Clara; Pilati, Pierluigi
2013-04-01
The adaptive immune response is controlled by checkpoints represented by coinhibitory molecules, which are crucial for maintaining self-tolerance and minimizing collateral tissue damage under physiological conditions. A growing body of preclinical evidence supports the hypothesis that unleashing this immunological break might be therapeutically beneficial in the fight against cancer, as it would elicit an effective antitumor immune response. Remarkably, recent clinical trials have demonstrated that this novel strategy can be highly effective in the treatment of patients with cancer, as shown by the paradigmatic case of ipilimumab (a monoclonal antibody blocking the coinhibitory molecule cytotoxic T lymphocyte associated antigen-4 [CTLA4]) that is opening a new era in the therapeutic approach to a chemoresistant tumor such as cutaneous melanoma. In this review we summarize the biology of coinhibitory molecules, overview the experimental and clinical attempts to interfere with these immune checkpoints to treat cancer and critically discuss the challenges posed by such a promising antitumor modality. Copyright © 2013 Elsevier Ltd. All rights reserved.
Human Recombinant Insulin 1g - ug
NASA Technical Reports Server (NTRS)
2004-01-01
Proteins are the building blocks of our bodies and the living world around us. Within our bodies proteins make it possible for red blood cells to carry oxygen throughout the body. Others help transmit nerve impulses so we can hear, smell and feel the world around us. While others play a crucial role in preventing or causing disease. If the structure of a protein is known, then companies can develop new or improved drugs to fight the disease of which the protein is a part. To determine protein structure, researchers must grow near-perfect crystals of the protein. On Earth convection currents, sedimentation and other gravity-induced phenomena hamper crystal growth efforts. In microgravity researchers can grow near-perfect crystals in an environment free of these effects. Because of the enormous potential for new pharmaceutical products the Center for Macromolecular Crystallography--the NASA Commercial Space Center responsible for commercial protein crystal growth efforts has more than fifty major industry and academic partners. Research on crystals of human insulin could lead to improved treatments for diabetes.
2004-04-15
Proteins are the building blocks of our bodies and the living world around us. Within our bodies proteins make it possible for red blood cells to carry oxygen throughout the body. Others help transmit nerve impulses so we can hear, smell and feel the world around us. While others play a crucial role in preventing or causing disease. If the structure of a protein is known, then companies can develop new or improved drugs to fight the disease of which the protein is a part. To determine protein structure, researchers must grow near-perfect crystals of the protein. On Earth convection currents, sedimentation and other gravity-induced phenomena hamper crystal growth efforts. In microgravity researchers can grow near-perfect crystals in an environment free of these effects. Because of the enormous potential for new pharmaceutical products the Center for Macromolecular Crystallography--the NASA Commercial Space Center responsible for commercial protein crystal growth efforts has more than fifty major industry and academic partners. Research on crystals of human insulin could lead to improved treatments for diabetes.
Die another day: the obstacles facing fat people in accessing quality healthcare.
Pausé, Cat
2014-01-01
In this issue of Narrative Inquiries in Bioethics, fat individuals share their healthcare experiences. Through reading the narratives, it becomes clear that access to proper healthcare is often blocked for fat patients by a variety of things, including shame and fat stigma. From physical spaces in which they do not fit, to doctors who diagnose all of their problems as 'fat', similar themes are echoed across the stories. And common are the refrains for better treatment, less shame, and access to evidenced based care from educated providers. In this manuscript, I highlight common themes from the stories and integrate them with themes from the literature. I allow the two dissenting narratives to suggest other ways of thinking about fatness and well-being. And I conclude by suggesting ways to provide better access to quality healthcare for fat individuals.
LaFrate, Andrew L; Gunther, Jillian R; Carlson, Kathryn E; Katzenellenbogen, John A
2008-12-01
Most patients with hormone-responsive breast cancer eventually develop resistance to traditional antiestrogens such as tamoxifen, and this has become a major obstacle in their treatment. We prepared and characterized the activity of a series of 16 guanylhydrazone small molecules that are designed to block estrogen receptor (ER) activity through a non-traditional mechanism, by directly interfering with coactivator binding to agonist-liganded ER. The inhibitory activity of these compounds was determined in cell-based transcription assays using ER-responsive reporter gene and mammalian two-hybrid assays. Several of the compounds gave IC(50) values in the low micromolar range. Two secondary assays were used to confirm that these compounds were acting through the proposed non-traditional mode of estrogen inhibitory action and not as conventional antagonists at the ligand binding site.
Sex and age-level differences of walking time in preschool children on an obstacle frame
2012-01-01
Background Stepping over an obstacle is a kind of compound movement that makes walking more difficult, especially for preschool children. This study examines sex and age-level differences in walking time in preschool children on an obstacle frame. Methods The participants included 324 healthy preschool children: four-year-old boys (51) and girls (51), five-year-old boys (50) and girls (60), and six-year-old boys (62) and girls (50). A 5 cm- or 10 cm-high obstacle (depth 11.5 cm, width 23.5 cm) was set at the halfway point of a 200 cm × 10 cm walking course. Results The participants walked to the end of the course and back as fast as possible under three conditions: no obstacle, low obstacle and high obstacle. Walking time showed age-level differences in all conditions, but there were no differences in sex. Age levels were divided into two groups, with one group within the first six months of their birthday, and the second group within the last six months of that year. Walking time for children in the first half of their fourth year was longer than that of the five- and six-year-old children. In addition, for children in the last half of their fourth year, walking time was longer than both sexes in the last half of their fifth and sixth years. The children in the latter half of their fifth year had a longer walking time in the high obstacle condition than those in the last half of their sixth year. In the four-year-old participants, walking time was shorter with no obstacles than with a high obstacle frame. Conclusions In the above data, obstacle course walking time does not show a gender difference, except that the four-year-old participants needed longer than the five- and six-year-old children. Setting the obstacle 10 cm high also produced a different walking time in the five- and six-year-old participants. The high obstacle step test (10 cm) best evaluated the dynamic balance of preschool children. PMID:22738328
NASA Astrophysics Data System (ADS)
Simoëns, Serge; Wallace, James M.
As described in Part 1 [Simoëns et al., 2007. The flow across a street canyon of variable width—Part 1: kinematic description. Atmospheric Environment 41, 9002-9017] measurements have been made of the velocity field around and within the canyon formed by two obstacles placed on the wall of a turbulent boundary layer. Here in Part 2 measurements of the scalar dispersion of smoke released from a two-dimensional slot in the wall perpendicular to the mean flow and located parallel to and midway between these two square obstacles are presented. The Reynolds number of the boundary layer at the slot location without the obstacles in place was Rθ≈980. Statistical properties of the concentration field and the scalar fluxes in the streamwise plane are reported here for canyon openings that have been chosen based on characteristics of the kinematic description. These opening widths, expressed as multiples of the obstacle height, are 1 h, 4 h and 8 h. The mean concentration field revealed that the much of the scalar is trapped on the leeward side of the upstream obstacle before some of it escapes the canyon and is entrained on the roof of the upstream obstacle. It then is spread downstream by the turbulence in the wake of this obstacle. Surprisingly, the root mean square (rms) concentration field reveals that high concentration fluctuations exist in a zone where velocity field turbulence is very low. Measured streamwise scalar fluxes were found to be negative above the obstacles, whereas they are mainly positive between the obstacles. The measured wall normal scalar fluxes have an inverse behavior. Within the canyon, the scalar fluxes are greatest in the region between the large primary vortex, evident in the kinematic field, and the secondary vortex located in the corner of the leeward side of the upstream obstacle. In the flow above the obstacle roofs the wake of the upstream obstacle seems to dominate the scalar transport. Between the obstacles in and above the canyon, the existence of intermittent and intense events appear to prevent the modelling of these fluxes with a simple mean concentration gradient model.
Yiou, Eric; Artico, Romain; Teyssedre, Claudine A; Labaune, Ombeline; Fourcade, Paul
2016-01-01
Despite the abundant literature on obstacle crossing in humans, the question of how the central nervous system (CNS) controls postural stability during gait initiation with the goal to clear an obstacle remains unclear. Stabilizing features of gait initiation include anticipatory postural adjustments (APAs) and lateral swing foot placement. To answer the above question, 14 participants initiated gait as fast as possible in three conditions of obstacle height, three conditions of obstacle distance and one obstacle-free (control) condition. Each of these conditions was performed with two levels of temporal pressure: reaction-time (high-pressure) and self-initiated (low-pressure) movements. A mechanical model of the body falling laterally under the influence of gravity and submitted to an elastic restoring force is proposed to assess the effect of initial (foot-off) center-of-mass position and velocity (or "initial center-of-mass set") on the stability at foot-contact. Results showed that the anticipatory peak of mediolateral (ML) center-of-pressure shift, the initial ML center-of-mass velocity and the duration of the swing phase, of gait initiation increased with obstacle height, but not with obstacle distance. These results suggest that ML APAs are scaled with swing duration in order to maintain an equivalent stability across experimental conditions. This statement is strengthened by the results obtained with the mechanical model, which showed how stability would be degraded if there was no adaptation of the initial center-of-mass set to swing duration. The anteroposterior (AP) component of APAs varied also according to obstacle height and distance, but in an opposite way to the ML component. Indeed, results showed that the anticipatory peak of backward center-of-pressure shift and the initial forward center-of-mass set decreased with obstacle height, probably in order to limit the risk to trip over the obstacle, while the forward center-of-mass velocity at foot-off increased with obstacle distance, allowing a further step to be taken. These effects of obstacle height and distance were globally similar under low and high-temporal pressure. Collectively, these findings imply that the CNS is able to predict the potential instability elicited by the obstacle clearance and that it scales the spatiotemporal parameters of APAs accordingly.
Yiou, Eric; Artico, Romain; Teyssedre, Claudine A.; Labaune, Ombeline; Fourcade, Paul
2016-01-01
Despite the abundant literature on obstacle crossing in humans, the question of how the central nervous system (CNS) controls postural stability during gait initiation with the goal to clear an obstacle remains unclear. Stabilizing features of gait initiation include anticipatory postural adjustments (APAs) and lateral swing foot placement. To answer the above question, 14 participants initiated gait as fast as possible in three conditions of obstacle height, three conditions of obstacle distance and one obstacle-free (control) condition. Each of these conditions was performed with two levels of temporal pressure: reaction-time (high-pressure) and self-initiated (low-pressure) movements. A mechanical model of the body falling laterally under the influence of gravity and submitted to an elastic restoring force is proposed to assess the effect of initial (foot-off) center-of-mass position and velocity (or “initial center-of-mass set”) on the stability at foot-contact. Results showed that the anticipatory peak of mediolateral (ML) center-of-pressure shift, the initial ML center-of-mass velocity and the duration of the swing phase, of gait initiation increased with obstacle height, but not with obstacle distance. These results suggest that ML APAs are scaled with swing duration in order to maintain an equivalent stability across experimental conditions. This statement is strengthened by the results obtained with the mechanical model, which showed how stability would be degraded if there was no adaptation of the initial center-of-mass set to swing duration. The anteroposterior (AP) component of APAs varied also according to obstacle height and distance, but in an opposite way to the ML component. Indeed, results showed that the anticipatory peak of backward center-of-pressure shift and the initial forward center-of-mass set decreased with obstacle height, probably in order to limit the risk to trip over the obstacle, while the forward center-of-mass velocity at foot-off increased with obstacle distance, allowing a further step to be taken. These effects of obstacle height and distance were globally similar under low and high-temporal pressure. Collectively, these findings imply that the CNS is able to predict the potential instability elicited by the obstacle clearance and that it scales the spatiotemporal parameters of APAs accordingly. PMID:27656138
Human Robotic Study at Houghton Crater - virtual reality study from NASA Ames (FFC) Future Fight
NASA Technical Reports Server (NTRS)
2002-01-01
Human Robotic Study at Houghton Crater - virtual reality study from NASA Ames (FFC) Future Fight Central simulator tower L-R: Dr Geoffrey Briggs; Jen Jasper (seated); Dr Jan Akins and Mr. Tony Gross, Ames
Fighting the Flu with a Universal Vaccine | NIH MedlinePlus the Magazine
... Follow us Fighting the Flu with a Universal Vaccine Photo: iStock After a serious 2017–2018 flu ... have safely received seasonal flu vaccines. The universal vaccine should: Protect against multiple flu strains Be 75% ...
Supercomputers Join the Fight against Cancer – U.S. Department of Energy
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
The Department of Energy has some of the best supercomputers in the world. Now, they’re joining the fight against cancer. Learn about our new partnership with the National Cancer Institute and GlaxoSmithKline Pharmaceuticals.
Fighting terrorism in Africa: Benchmarking policy harmonization
NASA Astrophysics Data System (ADS)
Asongu, Simplice A.; Tchamyou, Vanessa S.; Minkoua N., Jules R.; Asongu, Ndemaze; Tchamyou, Nina P.
2018-02-01
This study assesses the feasibility of policy harmonization in the fight against terrorism in 53 African countries with data for the period 1980-2012. Four terrorism variables are used, namely: domestic, transnational, unclear and total terrorism dynamics. The empirical evidence is based on absolute beta catch-up and sigma convergence estimation techniques. There is substantial absence of catch-up. The lowest rate of convergence in terrorism is in landlocked countries for regressions pertaining to unclear terrorism (3.43% per annum for 174.9 years) while the highest rate of convergence is in upper-middle-income countries in domestic terrorism regressions (15.33% per annum for 39.13 years). After comparing results from the two estimation techniques, it is apparent that in the contemporary era, countries with low levels of terrorism are not catching-up their counterparts with high levels of terrorism. As a policy implication, whereas some common policies may be feasibly adopted for the fight against terrorism, the findings based on the last periodic phase (2004-2012) are indicative that country-specific policies would better pay-off in the fight against terrorism than blanket common policies. Some suggestions of measures in fighting transnational terrorism have been discussed in the light of an anticipated surge in cross-national terrorism incidences in the coming years.
Huang, Shu-Ping; Garcia, Mark; Fuller, Adam
2018-01-01
In many species, males tend to behave more aggressively than females and female aggression often occurs during particular life stages such as maternal defence of offspring. Though many studies have revealed differences in aggression between the sexes, few studies have compared the sexes in terms of their neuroendocrine responses to contest experience. We investigated sex differences in the endocrine response to social challenge using mangrove rivulus fish, Kryptolebias marmoratus. In this species, sex is determined environmentally, allowing us to produce males and hermaphrodites with identical genotypes. We hypothesized that males would show elevated androgen levels (testosterone and 11-ketotestosterone) following social challenge but that hermaphrodite responses might be constrained by having to maintain both testicular and ovarian tissue. To test this hypothesis, we staged fights between males and between hermaphrodites, and then compared contest behaviour and hormone responses between the sexes. Hermaphrodites had significantly higher oestradiol but lower 11-ketotestosterone than males before contests. Males took longer to initiate contests but tended to fight more aggressively and sustain longer fights than hermaphrodites. Males showed a dramatic post-fight increase in 11-ketotestosterone but hermaphrodites did not. Thus, despite being genetically identical, males and hermaphrodites exhibit dramatically different fighting strategies and endocrine responses to contests. PMID:29765691
Sex-based differences in plasma chemistry and cardiac marker test results in Siamese fighting fowl.
Sribhen, Choosri; Choothesa, Apassara; Songserm, Thaveesak; Issariyodom, Supaporn; Sribhen, Kosit
2006-09-01
Variations in the results of plasma chemistry analysis as a function of sex have rarely been demonstrated in avian species. The aim of the present study was to investigate sex-related differences in values for routine biochemical variables, including conventional muscle enzymes, and novel cardiac markers in female and male Siamese fighting fowl. Plasma chemistry analytes and cardiac marker proteins (creatine kinase-MB and cardiac troponin T) were measured in 70 Siamese fighting fowl using automated chemistry and immunoassay analyzers. Data were compared by 2-tailed t tests between sexes, and Spearman rank correlation between conventional and novel cardiac markers. Male fowl had significantly higher uric acid concentration and gamma-glutamyltransferase activity; whereas, female fowl had significantly higher total cholesterol, triglycerides, and calcium concentrations, and alkaline phosphatase activity. As compared with female fowl, the fighting cocks also had significantly higher plasma concentrations of creatine kinase-MB and cardiac troponin T. Significant correlations between cardiac troponin T, but not creatine kinase-MB, and the activities of conventional muscle enzymes (creatine kinase, aspartate aminotransferase and lactate dehydrogenase) were observed in male but not in female fowl. These results indicate that sex-specific differences exist for several biochemical parameters and cardiac marker proteins in fighting fowl, and that such differences should be considered in interpreting laboratory test results.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-22
... Minimums & Obstacle DP, Orig-A Red Oak, IA, Red Oak Muni, Takeoff Minimums & Obstacle DP, Amdt 3 Storm Lake, IA, Storm Lake Muni, Takeoff Minimums & Obstacle DP, Orig Dwight, IL, Dwight, Takeoff Minimums..., Florence Rgnl, RNAV (GPS) RWY 9, Orig-A Spearfish, SD, Black Hills-Clydes Ice Field, RNAV (GPS) RWY 13...
Student with Asperger's Overcomes Obstacles: Devon's Journey to Independence
ERIC Educational Resources Information Center
Williams, Sarah Blackwelder
2010-01-01
Devon is a bright, engaging 22-year-old with a proud sense of accomplishment. He believes that while people encounter obstacles during their lives, these obstacles can be overcome with motivation and perseverance. Devon says people simply need to identify what they value, set goals and move beyond the obstacles. Devon has been faced with multiple…
Inertial navigation sensor integrated obstacle detection system
NASA Technical Reports Server (NTRS)
Bhanu, Bir (Inventor); Roberts, Barry A. (Inventor)
1992-01-01
A system that incorporates inertial sensor information into optical flow computations to detect obstacles and to provide alternative navigational paths free from obstacles. The system is a maximally passive obstacle detection system that makes selective use of an active sensor. The active detection typically utilizes a laser. Passive sensor suite includes binocular stereo, motion stereo and variable fields-of-view. Optical flow computations involve extraction, derotation and matching of interest points from sequential frames of imagery, for range interpolation of the sensed scene, which in turn provides obstacle information for purposes of safe navigation.
A method of real-time detection for distant moving obstacles by monocular vision
NASA Astrophysics Data System (ADS)
Jia, Bao-zhi; Zhu, Ming
2013-12-01
In this paper, we propose an approach for detection of distant moving obstacles like cars and bicycles by a monocular camera to cooperate with ultrasonic sensors in low-cost condition. We are aiming at detecting distant obstacles that move toward our autonomous navigation car in order to give alarm and keep away from them. Method of frame differencing is applied to find obstacles after compensation of camera's ego-motion. Meanwhile, each obstacle is separated from others in an independent area and given a confidence level to indicate whether it is coming closer. The results on an open dataset and our own autonomous navigation car have proved that the method is effective for detection of distant moving obstacles in real-time.
Mapping cis-Regulatory Domains in the Human Genome UsingMulti-Species Conservation of Synteny
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ahituv, Nadav; Prabhakar, Shyam; Poulin, Francis
2005-06-13
Our inability to associate distant regulatory elements with the genes that they regulate has largely precluded their examination for sequence alterations contributing to human disease. One major obstacle is the large genomic space surrounding targeted genes in which such elements could potentially reside. In order to delineate gene regulatory boundaries we used whole-genome human-mouse-chicken (HMC) and human-mouse-frog (HMF) multiple alignments to compile conserved blocks of synteny (CBS), under the hypothesis that these blocks have been kept intact throughout evolution at least in part by the requirement of regulatory elements to stay linked to the genes that they regulate. A totalmore » of 2,116 and 1,942 CBS>200 kb were assembled for HMC and HMF respectively, encompassing 1.53 and 0.86 Gb of human sequence. To support the existence of complex long-range regulatory domains within these CBS we analyzed the prevalence and distribution of chromosomal aberrations leading to position effects (disruption of a genes regulatory environment), observing a clear bias not only for mapping onto CBS but also for longer CBS size. Our results provide a genome wide data set characterizing the regulatory domains of genes and the conserved regulatory elements within them.« less
Mager-Mardeusz, Haleigh; Lenz, Cosima; Kominski, Gerald F
2017-04-01
Changing the Medicaid program is a top priority for the Republican party. Common themes from GOP proposals include converting Medicaid from a jointly financed entitlement benefit to a form of capped federal financing. While proponents of this reform argue that it would provide greater flexibility and a more predictable budget for state governments, serious consequences would likely result for Medicaid enrollees and state governments. Under all three scenarios promoted by Republicans--block grants, capped allotments, and per capita caps—most states would face increased costs. For all three scenarios, the capped nature of the funding guarantees that the real value of funds would decrease in future years relative to what would be expected from growth under the current program. Although the federal government would undoubtedly realize savings from all three scenarios, the impact might lead states to reduce benefits and services, create waiting lists, impose cost-sharing on a traditionally low-income enrollee population, or impose other obstacles to coverage. Nationally, as many as 20.5 million Americans stand to lose coverage under the proposed Medicaid changes. In California, up to 6 million people could lose coverage if changes to the Medicaid program were coupled with the repeal of coverage for the expansion population.
A Laser-Based Measuring System for Online Quality Control of Car Engine Block.
Li, Xing-Qiang; Wang, Zhong; Fu, Lu-Hua
2016-11-08
For online quality control of car engine production, pneumatic measurement instrument plays an unshakeable role in measuring diameters inside engine block because of its portability and high-accuracy. To the limitation of its measuring principle, however, the working space between the pneumatic device and measured surface is too small to require manual operation. This lowers the measuring efficiency and becomes an obstacle to perform automatic measurement. In this article, a high-speed, automatic measuring system is proposed to take the place of pneumatic devices by using a laser-based measuring unit. The measuring unit is considered as a set of several measuring modules, where each of them acts like a single bore gauge and is made of four laser triangulation sensors (LTSs), which are installed on different positions and in opposite directions. The spatial relationship among these LTSs was calibrated before measurements. Sampling points from measured shaft holes can be collected by the measuring unit. A unified mathematical model was established for both calibration and measurement. Based on the established model, the relative pose between the measuring unit and measured workpiece does not impact the measuring accuracy. This frees the measuring unit from accurate positioning or adjustment, and makes it possible to realize fast and automatic measurement. The proposed system and method were finally validated by experiments.
Loeffler, David A; Klaver, Andrea C
2017-11-01
Specific antibody concentrations are frequently measured in serum (and plasma and intravenous immunoglobulin) samples by enzyme-linked immunosorbent assay (ELISA). The standard negative control involves incubation of buffer alone on antigen-coated wells. The immunoreactivity that develops in antigen-coated wells in which diluted serum has been incubated is assumed to represent specific antibody binding. This approach can result in marked overestimation of specific antibody levels, because serum contains specific polyvalent antibodies which bind, primarily with low affinity, to multiple antigens (including those on ELISA plates) despite the use of blocking agents. Non-denaturing purification of serum IgG, followed by assessment of the antigen binding or antigen-binding affinity of this purified IgG, can reduce but not eliminate the problem of polyvalent antibody binding in indirect ELISAs. Alternatively, polyvalent antibody binding can be estimated by incubating a diluted serum sample on wells coated with an irrelevant protein (such as bovine serum albumin or a scrambled peptide sequence) or buffer alone, then subtracting this reactivity from the sample's binding to wells coated with the antigen of interest. Polyvalent binding of immunoglobulins must be accounted for in order to obtain accurate ELISA measurements of serum, plasma, or intravenous immunoglobulin antibodies. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA helicopter helps fight fire at KSC
NASA Technical Reports Server (NTRS)
2000-01-01
A NASA helicopter takes off to bring water to fight a small fire on Kennedy Space Center grounds. The site is between Kennedy Parkway North and the Indian River. The fire is one of many throughout Central Florida, which is suffering from drought.
Scriptotherapy: A Technique for Conflict Resolution.
ERIC Educational Resources Information Center
Johnson, Roy E.
Part 1 of this dissertation contains an introductory chapter entitled, "The Children Shout Fight Fight," in which the written analytical process named Scriptotherapy is discussed. In Chapter 1, "Early Adolescence an Ongoing Process," early adolescent growth and development, the process of moral development, temperament types…
ERIC Educational Resources Information Center
Waco, Alice
1982-01-01
Describes the development and implementation of a week-long "Women's History Week" program in a California high school. Using extracurricular workshops and traditional classroom activities, the program was designed to raise student and faculty awareness of sexism. The author describes ways they overcame logistical problems and administrative…
How Captain Amerika uses neural networks to fight crime
NASA Technical Reports Server (NTRS)
Rogers, Steven K.; Kabrisky, Matthew; Ruck, Dennis W.; Oxley, Mark E.
1994-01-01
Artificial neural network models can make amazing computations. These models are explained along with their application in problems associated with fighting crime. Specific problems addressed are identification of people using face recognition, speaker identification, and fingerprint and handwriting analysis (biometric authentication).
Racing Against Lung Cancer: Imaging Tools Help Patient in Cancer Fight
... Against Lung Cancer Follow us Racing Against Lung Cancer Imaging tools help patient in cancer fight Photo: Courtesy of Ted Simon In early ... primary care doctor. The diagnosis? Stage 4 lung cancer—advanced cancer that had already spread to some ...
Florence Nightingale would have taken on the political fight, and so should we.
Owen, Michael
2016-05-11
I agree with Mike Travis' comments (letters April 20) about the role and responsibilities of the trade union movement, and those of the RCN in caring for and fighting politically on behalf of nurses at all levels.
NASA Astrophysics Data System (ADS)
Kenfack, Joseph; Bignom, Blaise
2015-04-01
Central Africa owns important renewable energy potential, namely hydro, solar and biomass. This important potential is still suffering from poor development up to the point where the sub region is still abundantly using the fossil energy and biomass as main power source. This is harmful to the climate and the situation is still ongoing. The main cause of the poor use of renewable energy is the poor management of resources by governments who have not taken the necessary measures to boost the renewable energy sector. Since the region is experiencing power shortage, thermal plants are among other solutions planned or under construction. Firewood is heavily used in remote areas without a sustainability program behind. This solution is not environment friendly and hence is not a long term solution. Given the fact that the region has the highest hydro potential of the continent, up to one-quarter of the world's tropical forest, important oil production with poor purchase power, the aim of this paper is to identify actions for improved access to sustainable, friendly, affordable energy services to users as well as a significant improvement of energy infrastructure in Central Africa and the promotion of small hydro and other renewable energy. The work will show at first the potential for the three primary energy sources which are solar, biomass and hydro while showing where available the level of development, with an emphasis on small hydro. Then identified obstacles for the promotion of clean energy will be targeted. From lessons learned, suggestions will be made to help the countries develop an approach aiming at developing good clean energy policy to increase the status of renewable energy and better contribute to fight against climate change. Cameroon has a great renewable energy potential and some data are available on energy. From the overview of institutional structure reform of the Cameroon power sector and assessments, specific suggestions based on the weaknesses of the current management of renewable energy sources will be made for the enhancement of the renewable energy and hence sustain energy access and security in general and in remote areas in particular where the fight against poverty is more difficult. We will use several documents, soft and hard from institutions in the region and abroad, and maps when available. |End Text|
Kim, Aram; Zhou, Zixuan; Kretch, Kari S; Finley, James M
2017-07-01
The ability to successfully navigate obstacles in our environment requires integration of visual information about the environment with estimates of our body's state. Previous studies have used partial occlusion of the visual field to explore how information about the body and impending obstacles are integrated to mediate a successful clearance strategy. However, because these manipulations often remove information about both the body and obstacle, it remains to be seen how information about the lower extremities alone is utilized during obstacle crossing. Here, we used an immersive virtual reality (VR) interface to explore how visual feedback of the lower extremities influences obstacle crossing performance. Participants wore a head-mounted display while walking on treadmill and were instructed to step over obstacles in a virtual corridor in four different feedback trials. The trials involved: (1) No visual feedback of the lower extremities, (2) an endpoint-only model, (3) a link-segment model, and (4) a volumetric multi-segment model. We found that the volumetric model improved success rate, placed their trailing foot before crossing and leading foot after crossing more consistently, and placed their leading foot closer to the obstacle after crossing compared to no model. This knowledge is critical for the design of obstacle negotiation tasks in immersive virtual environments as it may provide information about the fidelity necessary to reproduce ecologically valid practice environments.
Darekar, Anuja; Lamontagne, Anouk; Fung, Joyce
2015-04-01
Circumvention around an obstacle entails a dynamic interaction with the obstacle to maintain a safe clearance. We used a novel mathematical interpolation method based on the modified Shepard's method of Inverse Distance Weighting to compute dynamic clearance that reflected this interaction as well as minimal clearance. This proof-of-principle study included seven young healthy, four post-stroke and four healthy age-matched individuals. A virtual environment designed to assess obstacle circumvention was used to administer a locomotor (walking) and a perceptuo-motor (navigation with a joystick) task. In both tasks, participants were asked to navigate towards a target while avoiding collision with a moving obstacle that approached from either head-on, or 30° left or right. Among young individuals, dynamic clearance did not differ significantly between obstacle approach directions in both tasks. Post-stroke individuals maintained larger and smaller dynamic clearance during the locomotor and the perceptuo-motor task respectively as compared to age-matched controls. Dynamic clearance was larger than minimal distance from the obstacle irrespective of the group, task and obstacle approach direction. Also, in contrast to minimal distance, dynamic clearance can respond differently to different avoidance behaviors. Such a measure can be beneficial in contrasting obstacle avoidance behaviors in different populations with mobility problems. Copyright © 2015 Elsevier B.V. All rights reserved.
A Monocular Vision Sensor-Based Obstacle Detection Algorithm for Autonomous Robots.
Lee, Tae-Jae; Yi, Dong-Hoon; Cho, Dong-Il Dan
2016-03-01
This paper presents a monocular vision sensor-based obstacle detection algorithm for autonomous robots. Each individual image pixel at the bottom region of interest is labeled as belonging either to an obstacle or the floor. While conventional methods depend on point tracking for geometric cues for obstacle detection, the proposed algorithm uses the inverse perspective mapping (IPM) method. This method is much more advantageous when the camera is not high off the floor, which makes point tracking near the floor difficult. Markov random field-based obstacle segmentation is then performed using the IPM results and a floor appearance model. Next, the shortest distance between the robot and the obstacle is calculated. The algorithm is tested by applying it to 70 datasets, 20 of which include nonobstacle images where considerable changes in floor appearance occur. The obstacle segmentation accuracies and the distance estimation error are quantitatively analyzed. For obstacle datasets, the segmentation precision and the average distance estimation error of the proposed method are 81.4% and 1.6 cm, respectively, whereas those for a conventional method are 57.5% and 9.9 cm, respectively. For nonobstacle datasets, the proposed method gives 0.0% false positive rates, while the conventional method gives 17.6%.
A game theory-based obstacle avoidance routing protocol for wireless sensor networks.
Guan, Xin; Wu, Huayang; Bi, Shujun
2011-01-01
The obstacle avoidance problem in geographic forwarding is an important issue for location-based routing in wireless sensor networks. The presence of an obstacle leads to several geographic routing problems such as excessive energy consumption and data congestion. Obstacles are hard to avoid in realistic environments. To bypass obstacles, most routing protocols tend to forward packets along the obstacle boundaries. This leads to a situation where the nodes at the boundaries exhaust their energy rapidly and the obstacle area is diffused. In this paper, we introduce a novel routing algorithm to solve the obstacle problem in wireless sensor networks based on a game-theory model. Our algorithm forms a concave region that cannot forward packets to achieve the aim of improving the transmission success rate and decreasing packet transmission delays. We consider the residual energy, out-degree and forwarding angle to determine the forwarding probability and payoff function of forwarding candidates. This achieves the aim of load balance and reduces network energy consumption. Simulation results show that based on the average delivery delay, energy consumption and packet delivery ratio performances our protocol is superior to other traditional schemes.
Performance and three-dimensional kinematics of bipedal lizards during obstacle negotiation.
Olberding, Jeffrey P; McBrayer, Lance D; Higham, Timothy E
2012-01-15
Bipedal running is common among lizard species, but although the kinematics and performance of this gait have been well characterized, the advantages in biologically relevant situations are still unclear. Obstacle negotiation is a task that is ecologically relevant to many animals while moving at high speeds, such as during bipedal running, yet little is known about how obstacles impact locomotion and performance. We examined the effects of obstacle negotiation on the kinematics and performance of lizards during bipedal locomotion. We quantified three-dimensional kinematics from high-speed video (500 Hz) of six-lined racerunners (Aspidoscelis sexlineata) running on a 3 m racetrack both with and without an obstacle spanning the width of the track. The lizards did not alter their kinematics prior to contacting the obstacle. Although contact with the obstacle caused changes to the hindlimb kinematics, mean forward speed did not differ between treatments. The deviation of the vertical position of the body center of mass did not differ between treatments, suggesting that in the absence of a cost to overall performance, lizards forgo maintaining normal kinematics while negotiating obstacles in favor of a steady body center of mass height to avoid destabilizing locomotion.
Lukic, Luka; Santos-Victor, José; Billard, Aude
2014-04-01
We investigate the role of obstacle avoidance in visually guided reaching and grasping movements. We report on a human study in which subjects performed prehensile motion with obstacle avoidance where the position of the obstacle was systematically varied across trials. These experiments suggest that reaching with obstacle avoidance is organized in a sequential manner, where the obstacle acts as an intermediary target. Furthermore, we demonstrate that the notion of workspace travelled by the hand is embedded explicitly in a forward planning scheme, which is actively involved in detecting obstacles on the way when performing reaching. We find that the gaze proactively coordinates the pattern of eye-arm motion during obstacle avoidance. This study provides also a quantitative assessment of the coupling between the eye-arm-hand motion. We show that the coupling follows regular phase dependencies and is unaltered during obstacle avoidance. These observations provide a basis for the design of a computational model. Our controller extends the coupled dynamical systems framework and provides fast and synchronous control of the eyes, the arm and the hand within a single and compact framework, mimicking similar control system found in humans. We validate our model for visuomotor control of a humanoid robot.
Involvement of school students in fights with weapons: prevalence and associated factors in Brazil.
Melo, Alice Cristina Medeiros; Garcia, Leila Posenato
2016-09-22
Violence, as well as other behaviors, is often intensified during adolescence and early adulthood. The objective of this study is estimate the prevalence of Brazilian school students involvement in fights with weapons and to analyze the associated factors. This is a cross-sectional study using data from the National School Student Health Survey conducted in 2012 with 9 th grade elementary school students attending 2842 schools in all 27 Brazilian Federative Units. The outcome studied was involvement in fights with firearms and/or cold weapons in the 30 days prior to the interview. Poisson regression was used to estimate the prevalence ratios and 95 % confidence intervals (95 % CI). The analyses were stratified by sex. Fifty seven thousand and eighty nine female students and 52,015 male students were included; the prevalence of their involvement in fights with weapons was 7.2 (95 % CI 6.9-7.5) and 13.8 (95 % CI 13.4-14.3), respectively. In the adjusted analysis the factors associated with male student involvement in fights with weapons were: being older, working, having smoked a cigarette, consumed alcoholic beverages and illicit drugs recently, insomnia, not having any close friends, skipping classes without parental supervision, having suffered aggression from a family member, reporting feeling unsafe on the way to or from school and/or at school. The same associated factors were found among female students in addition to not living with their father and/or mother and having suffered bullying. There was no association with type of school in either sex. Involvement in fights with weapons was greater among older male students. Health-risk behaviors, mental health characteristics, parental supervision and context of violence also showed association with the outcomes.
Characteristics of Youth Seeking Emergency Care for Assault Injuries
Ranney, Megan; Newton, Manya; Woodhull, Whitney; Zimmerman, Marc; Walton, Maureen A.
2014-01-01
OBJECTIVE: To characterize youth seeking care for assault injuries, the context of violence, and previous emergency department (ED) service utilization to inform ED-based injury prevention. METHODS: A consecutive sample of youth (14–24) presenting to an urban ED with an assault injury completed a survey of partner violence, gun/knife victimization, gang membership, and context of the fight. RESULTS: A total of 925 youth entered the ED with an assault injury; 718 completed the survey (15.4% refused); 730 comparison youth were sampled. The fights leading to the ED visit occurred at home (37.6%) or on streets (30.4%), and were commonly with a known person (68.3%). Fights were caused by issues of territory (23.3%) and retaliation (8.9%); 20.8% of youth reported substance use before the fight. The assault-injured group reported more peer/partner violence and more gun experiences. Assault-injured youth reported higher past ED utilization for assault (odds ratio [OR]: 2.16) or mental health reasons (OR: 7.98). Regression analysis found the assault-injured youth had more frequent weapon use (OR: 1.25) and substance misuse (OR: 1.41). CONCLUSIONS: Assault-injured youth seeking ED care report higher levels of previous violence, weapon experience, and substance use compared with a comparison group seeking care for other complaints. Almost 10% of assault-injured youth had another fight-related ED visit in the previous year, and ∼5% had an ED visit for mental health. Most fights were with people known to them and for well-defined reasons, and were therefore likely preventable. The ED is a critical time to interact with youth to prevent future morbidity. PMID:24323994
Wilkinson, Anna V; Barrera, Stephanie L; McBride, Colleen M; Snyder, Denise C; Sloane, Richard; Meneses, Karen M; Pekmezi, Dorothy; Kraus, William E; Demark-Wahnefried, Wendy
2012-01-01
Cancer coping styles have been associated with several cancer-related outcomes. We examined whether baseline lifestyle behaviors differed between cancer survivors with fatalistic vs fighting-spirit coping styles, and whether there was differential response to two diet-exercise mailed-print interventions, one standardized and another individually tailored. Baseline differences by coping style are presented for 628 breast and prostate cancer survivors who participated in the FRESH START trial, along with multivariable analyses on rates of uptake by coping style and arm assignment for those completing the 2-year trial. At baseline, several differences were observed between fighting-spirits and fatalists, with the former significantly more likely to be white, younger, leaner, more-educated and at risk for depression, and less likely to consume 5+fruits and vegetables (F&V)/day (p-values<0.05). Improvements in physical activity were observed, with fighting-spirits exhibiting the greatest gains from baseline to Year-1, regardless of intervention type; but by Year-2, these differences diminished as fatalists gained ground. Moreover, fatalists who received standardized intervention material also charted steady improvements in F&V intake over the study period; by Year-2, 58.1% of fatalists achieved the 5-a-day goal vs 44.6% of fighting-spirits (p-value<0.05). Lifestyle behaviors and health message uptake differs by cancer coping style. Although tailored interventions appear most effective and minimize differential uptake, standardized interventions also can improve behaviors, though fighting-spirits may require additional boosters to maintain change. Copyright © 2010 John Wiley & Sons, Ltd.
2013-01-01
Background Millions of dollars are invested annually under the umbrella of national health systems strengthening. Global health initiatives provide funding for low- and middle-income countries through disease-oriented programmes while maintaining that the interventions simultaneously strengthen systems. However, it is as yet unclear which, and to what extent, system-level interventions are being funded by these initiatives, nor is it clear how much funding they allocate to disease-specific activities – through conventional ‘vertical-programming’ approach. Such funding can be channelled to one or more of the health system building blocks while targeting disease(s) or explicitly to system-wide activities. Methods We operationalized the World Health Organization health system framework of the six building blocks to conduct a detailed assessment of Global Fund health system investments. Our application of this framework framework provides a comprehensive quantification of system-level interventions. We applied this systematically to a random subset of 52 of the 139 grants funded in Round 8 of the Global Fund to Fight AIDS, Tuberculosis and Malaria (totalling approximately US$1 billion). Results According to the analysis, 37% (US$ 362 million) of the Global Fund Round 8 funding was allocated to health systems strengthening. Of that, 38% (US$ 139 million) was for generic system-level interventions, rather than disease-specific system support. Around 82% of health systems strengthening funding (US$ 296 million) was allocated to service delivery, human resources, and medicines & technology, and within each of these to two to three interventions. Governance, financing, and information building blocks received relatively low funding. Conclusions This study shows that a substantial portion of Global Fund’s Round 8 funds was devoted to health systems strengthening. Dramatic skewing among the health system building blocks suggests opportunities for more balanced investments with regard to governance, financing, and information system related interventions. There is also a need for agreement, by researchers, recipients, and donors, on keystone interventions that have the greatest system-level impacts for the cost-effective use of funds. Effective health system strengthening depends on inter-agency collaboration and country commitment along with concerted partnership among all the stakeholders working in the health system. PMID:23889824
Warren, Ashley E; Wyss, Kaspar; Shakarishvili, George; Atun, Rifat; de Savigny, Don
2013-07-26
Millions of dollars are invested annually under the umbrella of national health systems strengthening. Global health initiatives provide funding for low- and middle-income countries through disease-oriented programmes while maintaining that the interventions simultaneously strengthen systems. However, it is as yet unclear which, and to what extent, system-level interventions are being funded by these initiatives, nor is it clear how much funding they allocate to disease-specific activities - through conventional 'vertical-programming' approach. Such funding can be channelled to one or more of the health system building blocks while targeting disease(s) or explicitly to system-wide activities. We operationalized the World Health Organization health system framework of the six building blocks to conduct a detailed assessment of Global Fund health system investments. Our application of this framework framework provides a comprehensive quantification of system-level interventions. We applied this systematically to a random subset of 52 of the 139 grants funded in Round 8 of the Global Fund to Fight AIDS, Tuberculosis and Malaria (totalling approximately US$1 billion). According to the analysis, 37% (US$ 362 million) of the Global Fund Round 8 funding was allocated to health systems strengthening. Of that, 38% (US$ 139 million) was for generic system-level interventions, rather than disease-specific system support. Around 82% of health systems strengthening funding (US$ 296 million) was allocated to service delivery, human resources, and medicines & technology, and within each of these to two to three interventions. Governance, financing, and information building blocks received relatively low funding. This study shows that a substantial portion of Global Fund's Round 8 funds was devoted to health systems strengthening. Dramatic skewing among the health system building blocks suggests opportunities for more balanced investments with regard to governance, financing, and information system related interventions. There is also a need for agreement, by researchers, recipients, and donors, on keystone interventions that have the greatest system-level impacts for the cost-effective use of funds. Effective health system strengthening depends on inter-agency collaboration and country commitment along with concerted partnership among all the stakeholders working in the health system.
Negative obstacle detection by thermal signature
NASA Technical Reports Server (NTRS)
Matthies, Larry; Rankin, A.
2003-01-01
Detecting negative obstacles (ditches, potholes, and other depressions) is one of the most difficult problems in perception for autonomous, off-road navigation. Past work has largely relied on range imagery, because that is based on the geometry of the obstacle, is largely insensitive to illumination variables, and because there have not been other reliable alternatives. However, the visible aspect of negative obstacles shrinks rapidly with range, making them impossible to detect in time to avoid them at high speed. To relive this problem, we show that the interiors of negative obstacles generally remain warmer than the surrounding terrain throughout the night, making thermal signature a stable property for night-time negative obstacle detection. Experimental results to date have achieved detection distances 45% greater by using thermal signature than by using range data alone. Thermal signature is the first known observable with potential to reveal a deep negative obstacle without actually seeing far into it. Modeling solar illumination has potential to extend the usefulness of thermal signature through daylight hours.
Method for surmounting an obstacle by a robot vehicle
NASA Technical Reports Server (NTRS)
Wilcox, Brian H. (Inventor); Ohm, Timothy R. (Inventor)
1994-01-01
Surmounting obstacles in the path of a robot vehicle is accomplished by rotating the wheel forks of the vehicle about their transverse axes with respect to the vehicle body so as to shift most of the vehicle weight onto the rear wheels, and then driving the vehicle forward so as to drive the now lightly-loaded front wheels (only) over the obstacle. Then, after the front wheels have either surmounted or completely passed the obstacle (depending upon the length of the obstacle), the forks are again rotated about their transverse axes so as to shift most of the vehicle weight onto the front wheels. Then the vehicle is again driven forward so as to drive the now lightly-loaded rear wheels over the obstacle. Once the obstacle has been completely cleared and the vehicle is again on relatively level terrain, the forks are again rotated so as to uniformly distribute the vehicle weight between the front and rear wheels.
Decker, Leslie; Houser, Jeremy J.; Noble, John M.; Karst, Gregory M.; Stergiou, Nicholas
2009-01-01
This study aims to investigate the effects of shoe traction and obstacle height on lower extremity relative phase dynamics (analysis of intralimb coordination) during walking to better understand the mechanisms employed to avoid slippage following obstacle clearance. Ten participants walked at a self-selected pace during eight conditions: four obstacle heights (0%, 10%, 20%, and 40% of limb length) while wearing two pairs of shoes (low and high traction). A coordination analysis was used and phasing relationships between lower extremity segments were examined. The results demonstrated that significant behavioral changes were elicited under varied obstacle heights and frictional conditions. Both decreasing shoe traction and increasing obstacle height resulted in a more in-phase relationship between the interacting lower limb segments. The higher the obstacle and the lower the shoe traction, the more unstable the system became. These changes in phasing relationship and variability are indicators of alterations in coordinative behavior, which if pushed further may have lead to falling. PMID:19187929
Imaging objects behind small obstacles using axicon lens
NASA Astrophysics Data System (ADS)
Perinchery, Sandeep M.; Shinde, Anant; Murukeshan, V. M.
2017-06-01
Axicon lenses are conical prisms, which are known to focus a light source to a line comprising of multiple points along the optical axis. In this study, we analyze the potential of axicon lenses to view, image and record the object behind opaque obstacles in free space. The advantage of an axicon lens over a regular lens is demonstrated experimentally. Parameters such as obstacle size, object and the obstacle position in the context of imaging behind obstacles are tested using Zemax optical simulation. This proposed concept can be easily adapted to most of the optical imaging methods and microscopy modalities.
14 CFR 91.815 - Agricultural and fire fighting airplanes: Noise operating limitations.
Code of Federal Regulations, 2014 CFR
2014-01-01
...: Noise operating limitations. 91.815 Section 91.815 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... RULES Operating Noise Limits § 91.815 Agricultural and fire fighting airplanes: Noise operating limitations. (a) This section applies to propeller-driven, small airplanes having standard airworthiness...
ERIC Educational Resources Information Center
Academe, 2005
2005-01-01
In this new feature of the "Academe" journal, work by faculty members is highlighted who are mobilizing in support of academic freedom on their campuses and beyond. This September-October issue of the journal includes the following brief reflections from faculty all relating to the central theme of "fighting back": "Free…
NASA helicopter helps fight brush fire at KSC
NASA Technical Reports Server (NTRS)
2000-01-01
A NASA helicopter flies over fire-fighting equipment and personnel in order to drop its load of water on a wildfire at KSC. Before being extinguished, the fire burned about 20 acres at a site near gate 2C on Kennedy Parkway North (route 3).
Miller, Justin B.; Rissman, Robert A.; Bernick, Charles B.
2017-01-01
Abstract The role of the apolipoprotein e4 allele in moderating cognitive and neuroanatomical degeneration following repeated traumatic brain injury is controversial. Here we sought to establish the presence or absence of such a moderating relationship in a prospective study of active and retired boxers and mixed martial arts fighters. Fighters (n = 193) underwent cognitive evaluations, interviews regarding fight history, MRI of the brain, and genetic testing. We used a series of moderator analyses to test for any relationship of apolipoprotein genotype on structural volumes of brain regions previously established to be smaller in those with the most fight exposure, and on cognitive abilities also established to be sensitive to fight exposure. No moderating relationship was detected in any of the analyses. The results of this study suggest that there is no impact of apolipoprotein genotype on the apparent negative association between exposure to professional fighting and brain structure volume or aspects of cognition. PMID:27245878
Dyakonova, V E; Krushinsky, A L
2013-07-01
This study demonstrates that injection of the serotonin precursor 5-HTP causes substantial changes in the behavioral state, fighting behavior and ability to establish winner-loser relationships in male crickets (Gryllus bimaculatus). The characteristic features of 5-HTP-treated crickets include an elevated posture, enhanced general activity, longer duration of fighting, enhanced rival singing and a decreased ability to produce a clear fight loser. In addition, 5-HTP-treated males showed a slightly delayed latency to spread their mandibles, a decreased number of attacks and an equal potential to win in comparison to controls (physiological solution-treated males). The obtained results imply a significant role for serotonin in the regulation of social status-related behaviors in G. bimaculatus. Specifically, these data indicate that a decrease in serotonergic activity may be functionally important for the control of loser behavior and that some behavioral features of dominant male crickets are likely to be connected with the activation of the serotonergic system.
NASA Astrophysics Data System (ADS)
Rychkov, A. D.
2009-06-01
The work of a pulsed aerosol system for fire fighting is modelled, which is designed for fire fighting at oil storages and at the spills of oil products, whose vapors were modelled by gaseous methane. The system represents a device for separate installation, which consists of a charge of solid propellant (the gas generator) and a container with fine-dispersed powder of the flame-damper substance. The methane combustion was described by a one-stage gross-reaction, the influence of the concentration of vapors of the flame-damper substance on the combustion process was taken into account by reducing the pre-exponent factor in the Arrhenius law and was described by an empirical dependence. The computational experiment showed that the application of the pulsed aerosol system for fire fighting ensures an efficient transport of fine-dispersed aerosol particles of the flame-damping substance and its forming vapors to the combustion zone; the concentration of particles ensures the damping of the heat source.
Chabris, Christopher F; Weinberger, Adam; Fontaine, Matthew; Simons, Daniel J
2011-01-01
Inattentional blindness—the failure to see visible and otherwise salient events when one is paying attention to something else—has been proposed as an explanation for various real-world events. In one such event, a Boston police officer chasing a suspect ran past a brutal assault and was prosecuted for perjury when he claimed not to have seen it. However, there have been no experimental studies of inattentional blindness in real-world conditions. We simulated the Boston incident by having subjects run after a confederate along a route near which three other confederates staged a fight. At night only 35% of subjects noticed the fight; during the day 56% noticed. We manipulated the attentional load on the subjects and found that increasing the load significantly decreased noticing. These results provide evidence that inattentional blindness can occur during real-world situations, including the Boston case. PMID:23145232
Obstacle avoidance for redundant robots using configuration control
NASA Technical Reports Server (NTRS)
Seraji, Homayoun (Inventor); Colbaugh, Richard D. (Inventor); Glass, Kristin L. (Inventor)
1992-01-01
A redundant robot control scheme is provided for avoiding obstacles in a workspace during the motion of an end effector along a preselected trajectory by stopping motion of the critical point on the robot closest to the obstacle when the distance between is reduced to a predetermined sphere of influence surrounding the obstacle. Algorithms are provided for conveniently determining the critical point and critical distance.
Aggressive behavior of the white-eye mutant crickets, Gryllus bimaculatus.
Sakura, Midori; Watanabe, T; Aonuma, H
2012-01-01
Aggressive behavior of white-eye mutant crickets was investigated and compared with that of wild-type crickets. In the dark, wild-type pairs performed long-lasting fights with significantly higher aggressive levels compared to those in the light. In contrast, fights between two white-eye mutants were not significantly different with those between two wild-type crickets both in duration and the aggressive levels. Ethograms of aggressive behavior showed that the mutants could show typical sequentially escalating fight with the same behavioral categories as the wild-type crickets. These results indicate that the white-eye mutants are able to express normal aggressive behavior.
STS-42 crewmembers participate in JSC fire fighting training exercises
NASA Technical Reports Server (NTRS)
1991-01-01
STS-42 Discovery, Orbiter Vehicle (OV) 103, Payload Specialist Ulf D. Merbold (far left), fire fighting trainer (center), Payload Specialist Roberta L. Bondar (holding hose nozzle), and backup Payload Specialist Roger K. Crouch position water hoses in the direction of a blazing fire in JSC's Fire Training Pit. The crewmembers and backup are learning fire extinguishing techniques during fire fighting and fire training exercises held at JSC's Fire Training Pit located across from the Gilruth Center Bldg 207. Merbold is representing the European Space Agency (ESA) and Bondar is representing Canada during the International Microgravity Laboratory 1 (IML-1) mission aboard OV-103.
Said, Catherine M; Galea, Mary P; Lythgo, Noel
2013-03-01
Obstacle crossing is impaired in people following stroke. It is not known whether people with stroke who fail an obstacle crossing task have more falls or whether the gait adjustments used to cross an obstacle differ from those used by people who pass the task. The purposes of this study were (1) to identify whether a group of people with stroke who failed an obstacle crossing task had a greater incidence of falling and (2) to determine whether people who fail an obstacle crossing task utilize different gait adjustments. This was a prospective, observational study. Thirty-two participants with a recent stroke were recruited. Participants walked at self-selected speed and stepped over a 4-cm-high obstacle. Performance was rated as pass or fail, and spatiotemporal, center of mass (COM), and center of pressure (COP) data were collected. Prospective falls data were recorded for 20 participants over a 6-month period. The incidence of fallers was significantly higher (incidence rate=0.833) in the group that failed the obstacle crossing task than in the group that passed the task (incidence rate=0.143). The group that failed the task had a slower walking speed and greater normalized separation between the trail heel (unaffected support limb) and COM as the affected lead toe cleared the obstacle. This group exhibited greater normalized times from affected lead toe clearance to landing, unaffected trail toe clearance to landing, and affected trail toe-off to toe clearance. The sample size was small, and falls data were available for only 20 participants. Obstacle crossing is an important task to consider in people following stroke and may be useful in identifying those at risk of falls.
A bio-inspired kinematic controller for obstacle avoidance during reaching tasks with real robots.
Srinivasa, Narayan; Bhattacharyya, Rajan; Sundareswara, Rashmi; Lee, Craig; Grossberg, Stephen
2012-11-01
This paper describes a redundant robot arm that is capable of learning to reach for targets in space in a self-organized fashion while avoiding obstacles. Self-generated movement commands that activate correlated visual, spatial and motor information are used to learn forward and inverse kinematic control models while moving in obstacle-free space using the Direction-to-Rotation Transform (DIRECT). Unlike prior DIRECT models, the learning process in this work was realized using an online Fuzzy ARTMAP learning algorithm. The DIRECT-based kinematic controller is fault tolerant and can handle a wide range of perturbations such as joint locking and the use of tools despite not having experienced them during learning. The DIRECT model was extended based on a novel reactive obstacle avoidance direction (DIRECT-ROAD) model to enable redundant robots to avoid obstacles in environments with simple obstacle configurations. However, certain configurations of obstacles in the environment prevented the robot from reaching the target with purely reactive obstacle avoidance. To address this complexity, a self-organized process of mental rehearsals of movements was modeled, inspired by human and animal experiments on reaching, to generate plans for movement execution using DIRECT-ROAD in complex environments. These mental rehearsals or plans are self-generated by using the Fuzzy ARTMAP algorithm to retrieve multiple solutions for reaching each target while accounting for all the obstacles in its environment. The key aspects of the proposed novel controller were illustrated first using simple examples. Experiments were then performed on real robot platforms to demonstrate successful obstacle avoidance during reaching tasks in real-world environments. Copyright © 2012 Elsevier Ltd. All rights reserved.
Mesoscopic model for filament orientation in growing actin networks: the role of obstacle geometry
NASA Astrophysics Data System (ADS)
Weichsel, Julian; Schwarz, Ulrich S.
2013-03-01
Propulsion by growing actin networks is a universal mechanism used in many different biological systems, ranging from the sheet-like lamellipodium of crawling animal cells to the actin comet tails induced by certain bacteria and viruses in order to move within their host cells. Although the core molecular machinery for actin network growth is well preserved in all of these cases, the geometry of the propelled obstacle varies considerably. During recent years, filament orientation distribution has emerged as an important observable characterizing the structure and dynamical state of the growing network. Here we derive several continuum equations for the orientation distribution of filaments growing behind stiff obstacles of various shapes and validate the predicted steady state orientation patterns by stochastic computer simulations based on discrete filaments. We use an ordinary differential equation approach to demonstrate that for flat obstacles of finite size, two fundamentally different orientation patterns peaked at either ±35° or +70°/0°/ - 70° exhibit mutually exclusive stability, in agreement with earlier results for flat obstacles of very large lateral extension. We calculate and validate phase diagrams as a function of model parameters and show how this approach can be extended to obstacles with piecewise straight contours. For curved obstacles, we arrive at a partial differential equation in the continuum limit, which again is in good agreement with the computer simulations. In all cases, we can identify the same two fundamentally different orientation patterns, but only within an appropriate reference frame, which is adjusted to the local orientation of the obstacle contour. Our results suggest that two fundamentally different network architectures compete with each other in growing actin networks, irrespective of obstacle geometry, and clarify how simulated and electron tomography data have to be analyzed for non-flat obstacle geometries.
Al-Kaff, Abdulla; García, Fernando; Martín, David; De La Escalera, Arturo; Armingol, José María
2017-01-01
One of the most challenging problems in the domain of autonomous aerial vehicles is the designing of a robust real-time obstacle detection and avoidance system. This problem is complex, especially for the micro and small aerial vehicles, that is due to the Size, Weight and Power (SWaP) constraints. Therefore, using lightweight sensors (i.e., Digital camera) can be the best choice comparing with other sensors; such as laser or radar.For real-time applications, different works are based on stereo cameras in order to obtain a 3D model of the obstacles, or to estimate their depth. Instead, in this paper, a method that mimics the human behavior of detecting the collision state of the approaching obstacles using monocular camera is proposed. The key of the proposed algorithm is to analyze the size changes of the detected feature points, combined with the expansion ratios of the convex hull constructed around the detected feature points from consecutive frames. During the Aerial Vehicle (UAV) motion, the detection algorithm estimates the changes in the size of the area of the approaching obstacles. First, the method detects the feature points of the obstacles, then extracts the obstacles that have the probability of getting close toward the UAV. Secondly, by comparing the area ratio of the obstacle and the position of the UAV, the method decides if the detected obstacle may cause a collision. Finally, by estimating the obstacle 2D position in the image and combining with the tracked waypoints, the UAV performs the avoidance maneuver. The proposed algorithm was evaluated by performing real indoor and outdoor flights, and the obtained results show the accuracy of the proposed algorithm compared with other related works. PMID:28481277
Effect of visuospatial neglect on spatial navigation and heading after stroke.
Aravind, Gayatri; Lamontagne, Anouk
2017-06-09
Visuospatial neglect (VSN) impairs the control of locomotor heading in post-stroke individuals, which may affect their ability to safely avoid moving objects while walking. We aimed to compare VSN+ and VSN- stroke individuals in terms of changes in heading and head orientation in space while avoiding obstacles approaching from different directions and reorienting toward the final target. Stroke participants with VSN (VSN+) and without VSN (VSN-) walked in a virtual environment avoiding obstacles that approached contralesionally, head-on or ipsilesionally. Measures of obstacle avoidance (onset-of-heading change, maximum mediolateral deviation) and target alignment (heading and head-rotation errors with respect to target) were compared across groups and obstacle directions. In total, 26 participants with right-hemisphere stroke participated (13 VSN+ and 13 VSN-; 24 males; mean age 60.3 years, range 48 to 72 years). A larger proportion of VSN+ (75%) than VSN- (38%) participants collided with contralesional and head-on obstacles. For VSN- participants, deviating to the same side as the obstacle was a safe strategy to avoid diagonal obstacles and deviating to the opposite-side led to occasional collisions. VSN+ participants deviated ipsilesionally, displaying same-side and opposite-side strategies for ipsilesional and contralesional obstacles, respectively. Overall, VSN+ participants showed greater distances at onset-of-heading change, smaller maximum mediolateral deviation and larger errors in target alignment as compared with VSN- participants. The ipsilesional bias arising from VSN influences the modulation of heading in response to obstacles and, along with the adoption of the "riskier" strategies, contribute to the higher number colliders and poor goal-directed walking abilities in stroke survivors with VSN. Future research should focus on developing assessment and training tools for complex locomotor tasks such as obstacle avoidance in this population. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Accelerating confined premixed flames using a transverse slot jet
NASA Astrophysics Data System (ADS)
Richter, Joseph P.
2011-12-01
An experimental study of the transient interaction of a premixed laminar methane-air flame propagating into a transverse fluidic obstacle is considered. The de agration-to-detonation transition (DDT) mechanism for use in pulse detonation engines (PDE) is the main but not only motivation for this study. When DDT is initiated through the use of solid obstacles, the system incurs a drag penalty and subsequent total pressure losses due to the physical obstacle impeding on the flow. This study utilizes a fluidic obstacle to generate flame acceleration without the subsequent penalties associated with form drag of a solid obstacle. The experimental setup was designed specifically for non-intrusive optical measurement techniques such as schlieren, CH* chemiluminescence and digital particle image velocimetry (DPIV). The channel utilizes a length to width aspect ratio of L/W = 6, and was chosen along with the fuel (CH4) to guarantee the impossibility of excessive overpressures associated with unanticipated detonations. The mixture is ignited in the center of the closed end of the channel, and the flame propagates towards the obstacle located at 3.1H. The medium emitted from the slot-jet orifice is the same methane-air mixture used to fill the channel and is released post ignition to allow an interaction with the laminar propagating flame. A comparison of this transverse fluidic slot jet obstacle is made to four different solid obstacle geometries at various blockage ratios (BR) and at stoichiometric and lean (φ = 0:88) equivalence ratios. The results of this study show that a transverse slot jet is capable of increasing heat release, flame surface area and subsequently flame speed compared to that of any tested solid obstacle with similar maximum flame deflection over an obstacle.
NASA helicopter helps fight brush fire at KSC
NASA Technical Reports Server (NTRS)
2000-01-01
A NASA helicopter dips its fire-fighting bucket into the river to pick up and deliver a cargo of water to a wildfire at KSC. Before being extinguished, the fire burned about 20 acres at a site near gate 2C on Kennedy Parkway North (route 3).
Keeping Children Active: What You Can Do to Fight Childhood Obesity
ERIC Educational Resources Information Center
Pica, Rae
2009-01-01
In this article, the author talks about childhood obesity and explores ways to fight this condition. The author shares some activities to get children moving to positively impact childhood obesity. These include: "Stand Up/Sit Down;" "Quick Clean-Up;" and "Get Ready Spaghetti."
Handling Alters Aggression and "Loser" Effect Formation in "Drosophila Melanogaster"
ERIC Educational Resources Information Center
Trannoy, Severine; Chowdhury, Budhaditya; Kravitz, Edward A.
2015-01-01
In "Drosophila," prior fighting experience influences the outcome of later contests: losing a fight increases the probability of losing second contests, thereby revealing "loser" effects that involve learning and memory. In these experiments, to generate and quantify the behavioral changes observed as consequences of losing…
ERIC Educational Resources Information Center
Hanson, Dan
2011-01-01
Fight songs such as "The Victors" and "Notre Dame Victory March" have become part of the American music lexicon. Along with their sister songs, alma maters, they stir memories of carefree college days, elicit feelings of pride, and sometimes--especially fight songs--poke fun at athletic foes. They are the embodiment of…
14 CFR 36.1583 - Noncomplying agricultural and fire fighting airplanes.
Code of Federal Regulations, 2013 CFR
2013-01-01
... airplanes. 36.1583 Section 36.1583 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Limitations and Information § 36.1583 Noncomplying agricultural and fire fighting airplanes. (a) This section applies to propeller-driven, small airplanes that— (1) Are designed for “agricultural aircraft operations...
14 CFR 36.1583 - Noncomplying agricultural and fire fighting airplanes.
Code of Federal Regulations, 2011 CFR
2011-01-01
... airplanes. 36.1583 Section 36.1583 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Limitations and Information § 36.1583 Noncomplying agricultural and fire fighting airplanes. (a) This section applies to propeller-driven, small airplanes that— (1) Are designed for “agricultural aircraft operations...
14 CFR 36.1583 - Noncomplying agricultural and fire fighting airplanes.
Code of Federal Regulations, 2012 CFR
2012-01-01
... airplanes. 36.1583 Section 36.1583 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Limitations and Information § 36.1583 Noncomplying agricultural and fire fighting airplanes. (a) This section applies to propeller-driven, small airplanes that— (1) Are designed for “agricultural aircraft operations...
14 CFR 36.1583 - Noncomplying agricultural and fire fighting airplanes.
Code of Federal Regulations, 2014 CFR
2014-01-01
... airplanes. 36.1583 Section 36.1583 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Limitations and Information § 36.1583 Noncomplying agricultural and fire fighting airplanes. (a) This section applies to propeller-driven, small airplanes that— (1) Are designed for “agricultural aircraft operations...
Fighting Illiteracy in the Arab World
ERIC Educational Resources Information Center
Hammud, Muwafaq Abu; Jarrar, Amani G.
2017-01-01
Illiteracy in the Arab world is becoming an urgent necessity particularly facing problems of poverty, ignorance, extremism, which impede the required economic, social, political and cultural development processes. Extremism, violence and terrorism, in the Arab world, can only be eliminated by spreading of knowledge, fighting illiteracy. The study…
14 CFR 36.1583 - Noncomplying agricultural and fire fighting airplanes.
Code of Federal Regulations, 2010 CFR
2010-01-01
... airplanes. 36.1583 Section 36.1583 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Limitations and Information § 36.1583 Noncomplying agricultural and fire fighting airplanes. (a) This section applies to propeller-driven, small airplanes that— (1) Are designed for “agricultural aircraft operations...
Fighting Downtown: A Training Necessity for the Heavy Brigade
2001-02-01
Concept Technology Demonstration, and the Army Transformation Urban Franchise exploration of future operations.”57 CAMTF has identified three...fighting in a downtown area with tall buildings and underground sewers and or subways , but it must also apply to the outlying urban sprawl that is now
Recognition of an obstacle in a flow using artificial neural networks.
Carrillo, Mauricio; Que, Ulices; González, José A; López, Carlos
2017-08-01
In this work a series of artificial neural networks (ANNs) has been developed with the capacity to estimate the size and location of an obstacle obstructing the flow in a pipe. The ANNs learn the size and location of the obstacle by reading the profiles of the dynamic pressure q or the x component of the velocity v_{x} of the fluid at a certain distance from the obstacle. Data to train the ANN were generated using numerical simulations with a two-dimensional lattice Boltzmann code. We analyzed various cases varying both the diameter and the position of the obstacle on the y axis, obtaining good estimations using the R^{2} coefficient for the cases under study. Although the ANN showed problems with the classification of very small obstacles, the general results show a very good capacity for prediction.
Simulation of Molecular Transport in Systems Containing Mobile Obstacles.
Polanowski, Piotr; Sikorski, Andrzej
2016-08-04
In this paper, we investigate the movement of molecules in crowded environments with obstacles undergoing Brownian motion by means of extensive Monte Carlo simulations. Our investigations were performed using the dynamic lattice liquid model, which was based on the cooperative movement concept and allowed to mimic systems at high densities where the motion of all elements (obstacles as well as moving particles) were highly correlated. The crowded environments are modeled on a two-dimensional triangular lattice containing obstacles (particles whose mobility was significantly reduced) moving by a Brownian motion. The subdiffusive motion of both elements in the system was analyzed. It was shown that the percolation transition does not exist in such systems in spite of the cooperative character of the particles' motion. The reduction of the obstacle mobility leads to the longer caging of liquid particles by mobile obstacles.
Non-native Ants Are Smaller than Related Native Ants.
McGlynn, Terrence P
1999-12-01
I compare the sizes of non-native and native ants to evaluate how worker size may be related to the ability of a species to invade new habitats. I compare the size of 78 non-native ant species belonging to 26 genera with the size of native congeneric species; native ants are larger than non-native ants in 22 of 26 genera. Ants were sorted by genera into fighting and nonfighting groups, based on observations of interspecific interactions with other ant species. In all of the genera with monomorphic worker castes that fight during competition, the non-native species were smaller than the native species. The genera that engage in combat had a higher frequency of significantly smaller size in non-native ants. I selected Wasmannia auropunctata for further studies, to compare native and non-native populations. Specimens of W. auropunctata from non-native populations were smaller than conspecific counterparts from its native habitat. I consider hypotheses to explain why non-native ants are smaller in size than native ants, including the role of colony size in interspecific fights, changes in life history, the release from intraspecific fighting, and climate. The discovery that fighting non-natives are smaller than their closest native relatives may provide insight into the mechanisms for success of non-native species, as well as the role of worker size and colony size during interspecific competition.
Obstacle Avoidance for Quadcopter using Ultrasonic Sensor
NASA Astrophysics Data System (ADS)
Fazlur Rahman, Muhammad; Adhy Sasongko, Rianto
2018-04-01
An obstacle avoidance system is being proposed. The system will combine available flight controller with a proposed avoidance method as a proof of concept. Quadcopter as a UAV is integrated with the system which consist of several modes in order to do avoidance. As the previous study, obstacle will be determined using ultrasonic sensor and servo. As result, the quadcopter will move according to its mode and successfully avoid obstacle.
Detecting Negative Obstacles by Use of Radar
NASA Technical Reports Server (NTRS)
Mittskus, Anthony; Lux, James
2006-01-01
Robotic land vehicles would be equipped with small radar systems to detect negative obstacles, according to a proposal. The term "negative obstacles" denotes holes, ditches, and any other terrain features characterized by abrupt steep downslopes that could be hazardous for vehicles. Video cameras and other optically based obstacle-avoidance sensors now installed on some robotic vehicles cannot detect obstacles under adverse lighting conditions. Even under favorable lighting conditions, they cannot detect negative obstacles. A radar system according to the proposal would be of the frequency-modulation/ continuous-wave (FM/CW) type. It would be installed on a vehicle, facing forward, possibly with a downward slant of the main lobe(s) of the radar beam(s) (see figure). It would utilize one or more wavelength(s) of the order of centimeters. Because such wavelengths are comparable to the characteristic dimensions of terrain features associated with negative hazards, a significant amount of diffraction would occur at such features. In effect, the diffraction would afford a limited ability to see corners and to see around corners. Hence, the system might utilize diffraction to detect corners associated with negative obstacles. At the time of reporting the information for this article, preliminary analyses of diffraction at simple negative obstacles had been performed, but an explicit description of how the system would utilize diffraction was not available.
Clogging and depinning of ballistic active matter systems in disordered media
NASA Astrophysics Data System (ADS)
Reichhardt, C.; Reichhardt, C. J. O.
2018-05-01
We numerically examine ballistic active disks driven through a random obstacle array. Formation of a pinned or clogged state occurs at much lower obstacle densities for the active disks than for passive disks. As a function of obstacle density, we identify several distinct phases including a depinned fluctuating cluster state, a pinned single-cluster or jammed state, a pinned multicluster state, a pinned gel state, and a pinned disordered state. At lower active disk densities, a drifting uniform liquid forms in the absence of obstacles, but when even a small number of obstacles are introduced, the disks organize into a pinned phase-separated cluster state in which clusters nucleate around the obstacles, similar to a wetting phenomenon. We examine how the depinning threshold changes as a function of disk or obstacle density and find a crossover from a collectively pinned cluster state to a disordered plastic depinning transition as a function of increasing obstacle density. We compare this to the behavior of nonballistic active particles and show that as we vary the activity from completely passive to completely ballistic, a clogged phase-separated state appears in both the active and passive limits, while for intermediate activity, a readily flowing liquid state appears and there is an optimal activity level that maximizes the flux through the sample.
Gurses, Ayse P; Carayon, Pascale; Wall, Melanie
2009-01-01
Objectives To study the impact of performance obstacles on intensive care nurses‘ workload, quality and safety of care, and quality of working life (QWL). Performance obstacles are factors that hinder nurses‘ capacity to perform their job and that are closely associated with their immediate work system. Data Sources/Study Setting Data were collected from 265 nurses in 17 intensive care units (ICUs) between February and August 2004 via a structured questionnaire, yielding a response rate of 80 percent. Study Design A cross-sectional study design was used. Data were analyzed by correlation analyses and structural equation modeling. Principal Findings Performance obstacles were found to affect perceived quality and safety of care and QWL of ICU nurses. Workload mediated the impact of performance obstacles with the exception of equipment-related issues on perceived quality and safety of care as well as QWL. Conclusions Performance obstacles in ICUs are a major determinant of nursing workload, perceived quality and safety of care, and QWL. In general, performance obstacles increase nursing workload, which in turn negatively affect perceived quality and safety of care and QWL. Redesigning the ICU work system to reduce performance obstacles may improve nurses‘ work. PMID:19207589
A Monocular Vision Sensor-Based Obstacle Detection Algorithm for Autonomous Robots
Lee, Tae-Jae; Yi, Dong-Hoon; Cho, Dong-Il “Dan”
2016-01-01
This paper presents a monocular vision sensor-based obstacle detection algorithm for autonomous robots. Each individual image pixel at the bottom region of interest is labeled as belonging either to an obstacle or the floor. While conventional methods depend on point tracking for geometric cues for obstacle detection, the proposed algorithm uses the inverse perspective mapping (IPM) method. This method is much more advantageous when the camera is not high off the floor, which makes point tracking near the floor difficult. Markov random field-based obstacle segmentation is then performed using the IPM results and a floor appearance model. Next, the shortest distance between the robot and the obstacle is calculated. The algorithm is tested by applying it to 70 datasets, 20 of which include nonobstacle images where considerable changes in floor appearance occur. The obstacle segmentation accuracies and the distance estimation error are quantitatively analyzed. For obstacle datasets, the segmentation precision and the average distance estimation error of the proposed method are 81.4% and 1.6 cm, respectively, whereas those for a conventional method are 57.5% and 9.9 cm, respectively. For nonobstacle datasets, the proposed method gives 0.0% false positive rates, while the conventional method gives 17.6%. PMID:26938540
Obstacle detectors for automated transit vehicles: A technoeconomic and market analysis
NASA Technical Reports Server (NTRS)
Lockerby, C. E.
1979-01-01
A search was conducted to identify the technical and economic characteristics of both NASA and nonNASA obstacle detectors. The findings, along with market information were compiled and analyzed for consideration by DOT and NASA in decisions about any future automated transit vehicle obstacle detector research, development, or applications project. Currently available obstacle detectors and systems under development are identified by type (sonic, capacitance, infrared/optical, guided radar, and probe contact) and compared with the three NASA devices selected as possible improvements or solutions to the problems in existing obstacle detection systems. Cost analyses and market forecasts individually for the AGT and AMTV markets are included.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stroemqvist, Martin H., E-mail: stromqv@kth.se
We study the problem of optimally controlling the solution of the obstacle problem in a domain perforated by small periodically distributed holes. The solution is controlled by the choice of a perforated obstacle which is to be chosen in such a fashion that the solution is close to a given profile and the obstacle is not too irregular. We prove existence, uniqueness and stability of an optimal obstacle and derive necessary and sufficient conditions for optimality. When the number of holes increase indefinitely we determine the limit of the sequence of optimal obstacles and solutions. This limit depends strongly onmore » the rate at which the size of the holes shrink.« less
Effect of form of obstacle on speed of crowd evacuation
NASA Astrophysics Data System (ADS)
Yano, Ryosuke
2018-03-01
This paper investigates the effect of the form of an obstacle on the time that a crowd takes to evacuate a room, using a toy model. Pedestrians are modeled as active soft matter moving toward a point with intended velocities. An obstacle is placed in front of the exit, and it has one of four shapes: a cylindrical column, a triangular prism, a quadratic prism, or a diamond prism. Numerical results indicate that the evacuation-completion time depends on the shape of the obstacle. Obstacles with a circular cylinder (C.C.) shape yield the shortest evacuation-completion time in the proposed model.
Research on robot mobile obstacle avoidance control based on visual information
NASA Astrophysics Data System (ADS)
Jin, Jiang
2018-03-01
Robots to detect obstacles and control robots to avoid obstacles has been a key research topic of robot control. In this paper, a scheme of visual information acquisition is proposed. By judging visual information, the visual information is transformed into the information source of path processing. In accordance with the established route, in the process of encountering obstacles, the algorithm real-time adjustment trajectory to meet the purpose of intelligent control of mobile robots. Simulation results show that, through the integration of visual sensing information, the obstacle information is fully obtained, while the real-time and accuracy of the robot movement control is guaranteed.
Choose Your Battlefield and Kill with a Borrowed Knife: Al Qaida’s Catalyst Strategy
2010-01-01
Interstate War, and the Rise of Rome : (London: University of California Press 2006) 262 33 Ibid 34 18 Carl Conetta, in his article “Dislocating...and fight the pagans all together as they fight you all together, Allah.൯ 39 Richard
Educational Targeting in the Fight against Poverty: Limits, Omissions and Opportunities
ERIC Educational Resources Information Center
Tarabini, Aina
2008-01-01
Educational targeting has become one of the hegemonic mechanisms in the fight against poverty. Both international organisms and developing countries support targeting as one of the best strategies in order to simultaneously guarantee poverty reduction and economic growth, and consequently to tackle the challenges generated by globalisation. The…
USDA-ARS?s Scientific Manuscript database
Pollination efficacy of the oligolectic bee Ptilothrix bombiformis was measured as the number of pollen grains delivered to virgin Hibiscus stigmas. Such specialized bee foragers are often assumed to be highly efficient pollinators. Intriguingly, however, we discovered females fight over host blooms...
My Children Are Always Fighting. Working with Parents.
ERIC Educational Resources Information Center
Allen, Patsy
1994-01-01
Discusses techniques that teachers and parents can use to help young children cope with the birth of a new sibling and reduce fighting amongst siblings. Young children need to understand what is taking place, what is expected of them, and how they should interact with their brother or sister. (MDM)
Naval Medical R and D News Special Edition: 2016 MHSRS Conference
2016-09-01
and Protect Against Dengue Virus At the Military Health System Research Symposium, Aug. 17, Lt. Brian Morrison, a scientist from Naval Medical...fight dengue virus. Fighting dengue is vital to operational health and readiness. This viral infection is spread through mosquito bites and can cause
ERIC Educational Resources Information Center
Thorne, Edward J., Ed.
1972-01-01
This special issue opens with an article by Franklyn S. Haiman, "The Fighting Word Doctrine: From Chaplinsky to Brown," in which he reviews the problem of the use of "fighting words" in public situations. He discusses this type of communication as one that borders individual and collective rights, and provides background information on significant…
Fighting Domestic and International Fraud in the Admissions and Registrar's Offices
ERIC Educational Resources Information Center
Koenig, Ann M.; Devlin, Edward
2012-01-01
The education sector is no stranger to fraud, unfortunately. This article provides best practice guidance in recognizing and dealing with fraud, with emphasis on domestic and international academic credential fraud. It includes practical approaches to academic document review and verification. Success in fighting fraud requires becoming informed,…
ERIC Educational Resources Information Center
Martz, Carlton
2001-01-01
This issue of "Bill of Rights in Action" explores issues raised by empires and imperial law. The first article, "Clash of Empires: The Fight for North America," looks at the clash of empires and the fight for North America during the 18th century. The second article, "When Roman Law Ruled the Western World," examines…
Germs and Hygiene - Multiple Languages
... አማርኛ ) Expand Section Cleaning to Prevent the Flu - English PDF Cleaning to Prevent the Flu - Amarɨñña / አማርኛ ( ... Disease Control and Prevention Fight the Flu Poster - English PDF Fight the Flu Poster - Amarɨñña / አማርኛ (Amharic) ...
MIT - Massachusetts Institute of Technology
energy cancer diversity global industry public service Solve The MIT Campaign for a Better World give to produce electricity Drug-carrying nanoparticles could help fight brain cancer Drug-carrying nanoparticles could help fight brain cancer New dispatching approach optimizes a city's taxi fleet New dispatching
Primary Education and the Fight against Alcoholism in Belgium at the Turn of the Century.
ERIC Educational Resources Information Center
De Vroede, Maurice
1985-01-01
Actions taken to counter alcoholism in Belgium toward the end of the 19th century are discussed. Why the primary school was enlisted in the fight against the social problem, what initiatives were developed, and what results were achieved are considered. (RM)
Fighting the Good Fight against Sweatshops.
ERIC Educational Resources Information Center
Callahan, Laurie
1999-01-01
Asserts that by educating young people and by setting an example, teachers and schools can play a significant part in the important crusade to eliminate sweatshops. Reports on what schools, businesses, and others are doing in this crusade. Puts forth ideas for how Catholic schools and the individual can help. (VWC)
It’s War Out There: Fighting for life with xenobiotic degrading enzymes
USDA-ARS?s Scientific Manuscript database
It’s War Out There: Fighting for life with xenobiotic degrading enzymes Beta-lactamase enzymes are well studied because of their tremendous impact on medicine. Their prominent role is in resistance to beta-lactam (four membered lactam ring) antibiotics including the first and most famous fungally d...
Generation of spiral waves pinned to obstacles in a simulated excitable system
NASA Astrophysics Data System (ADS)
Phantu, Metinee; Kumchaiseemak, Nakorn; Porjai, Porramain; Sutthiopad, Malee; Müller, Stefan C.; Luengviriya, Chaiya; Luengviriya, Jiraporn
2017-09-01
Pinning phenomena emerge in many dynamical systems. They are found to stabilize extreme conditions such as superconductivity and super fluidity. The dynamics of pinned spiral waves, whose tips trace the boundary of obstacles, also play an important role in the human health. In heart, such pinned waves cause longer tachycardia. In this article, we present two methods for generating pinned spiral waves in a simulated excitable system. In method A, an obstacle is set in the system prior to an ignition of a spiral wave. This method may be suitable only for the case of large obstacles since it often fails when used for small obstacles. In method B, a spiral wave is generated before an obstacle is placed at the spiral tip. With this method, a pinned spiral wave is always obtained, regardless the obstacle size. We demonstrate that after a transient interval the dynamics of the pinned spiral waves generated by the methods A and B are identical. The initiation of pinned spiral waves in both two- and three-dimensional systems is illustrated.
NASA Technical Reports Server (NTRS)
Plumer, Edward S.
1991-01-01
A technique is developed for vehicle navigation and control in the presence of obstacles. A potential function was devised that peaks at the surface of obstacles and has its minimum at the proper vehicle destination. This function is computed using a systolic array and is guaranteed not to have local minima. A feedfoward neural network is then used to control the steering of the vehicle using local potential field information. In this case, the vehicle is a trailer truck backing up. Previous work has demonstrated the capability of a neural network to control steering of such a trailer truck backing to a loading platform, but without obstacles. Now, the neural network was able to learn to navigate a trailer truck around obstacles while backing toward its destination. The network is trained in an obstacle free space to follow the negative gradient of the field, after which the network is able to control and navigate the truck to its target destination in a space of obstacles which may be stationary or movable.
Using distributed partial memories to improve self-organizing collective movements.
Winder, Ransom; Reggia, James A
2004-08-01
Past self-organizing models of collectively moving "particles" (simulated bird flocks, fish schools, etc.) have typically been based on purely reflexive agents that have no significant memory of past movements. We hypothesized that giving such individual particles a limited distributed memory of past obstacles they encountered could lead to significantly faster travel between goal destinations. Systematic computational experiments using six terrains that had different arrangements of obstacles demonstrated that, at least in some domains, this conjecture is true. Furthermore, these experiments demonstrated that improved performance over time came not only from the avoidance of previously seen obstacles, but also (surprisingly) immediately after first encountering obstacles due to decreased delays in circumventing those obstacles. Simulations also showed that, of the four strategies we tested for removal of remembered obstacles when memory was full and a new obstacle was to be saved, none was better than random selection. These results may be useful in interpreting future experimental research on group movements in biological populations, and in improving existing methodologies for control of collective movements in computer graphics, robotic teams, particle swarm optimization, and computer games.
Laser development for optimal helicopter obstacle warning system LADAR performance
NASA Astrophysics Data System (ADS)
Yaniv, A.; Krupkin, V.; Abitbol, A.; Stern, J.; Lurie, E.; German, A.; Solomonovich, S.; Lubashitz, B.; Harel, Y.; Engart, S.; Shimoni, Y.; Hezy, S.; Biltz, S.; Kaminetsky, E.; Goldberg, A.; Chocron, J.; Zuntz, N.; Zajdman, A.
2005-04-01
Low lying obstacles present immediate danger to both military and civilian helicopters performing low-altitude flight missions. A LADAR obstacle detection system is the natural solution for enhancing helicopter safety and improving the pilot situation awareness. Elop is currently developing an advanced Surveillance and Warning Obstacle Ranging and Display (SWORD) system for the Israeli Air Force. Several key factors and new concepts have contributed to system optimization. These include an adaptive FOV, data memorization, autonomous obstacle detection and warning algorithms and the use of an agile laser transmitter. In the present work we describe the laser design and performance and discuss some of the experimental results. Our eye-safe laser is characterized by its pulse energy, repetition rate and pulse length agility. By dynamically controlling these parameters, we are able to locally optimize the system"s obstacle detection range and scan density in accordance with the helicopter instantaneous maneuver.
Influence of obstacles on bubbles rising in water-saturated sand
NASA Astrophysics Data System (ADS)
Poryles, Raphaël; Varas, Germán; Vidal, Valérie
2017-06-01
This work investigates the dynamics of air rising through a water-saturated sand confined in a Hele- Shaw cell in which a circular obstacle is trapped. The air is injected at constant flow rate through a single nozzle at the bottom center of the cell. Without obstacle, in a similar configuration, previous studies pointed out the existence of a fluidized zone generated by the central upward gas motion which entrains two granular convection rolls on its sides. Here, a circular obstacle which diameter is of the order of the central air channel width is trapped at the vertical of the injection nozzle. We analyze the influence of the obstacle location on the size of the fluidized zone and its impact on the morphology of the central air channel. Finally, we quantify the variations of the granular free surface. Two configurations with multiple obstacles are also considered.
Overcoming obstacles to behavior change in diabetes self-management.
Hall, Rosemary F; Joseph, Dayle Hunt; Schwartz-Barcott, Donna
2003-01-01
This study describes how 5 individuals with type 2 diabetes overcame obstacles that interfered with maintaining behavior changes in diet, exercise, and self-monitoring of blood glucose (SMBG). In-depth interviews provided the framework for this descriptive study. During audiotaped, face-to-face, follow-up structured and unstructured interviews, the participants shared their experiences about obstacles encountered and strategies used to overcome them. Each case was examined independently, and all cases were then compared with each other. Obstacles that interfered with maintaining a diet plan were hunger, planned and unplanned meal events, and the desire for new foods. Physical illness and unexpected life events were obstacles to maintaining an exercise and SMBG plan. Health professionals who assist patients who are beginning behavior change or having difficult maintaining changes need to have an understanding of the various obstacles and how patients can maintain behavior changes over time.
Dynamics of spiral waves rotating around an obstacle and the existence of a minimal obstacle
NASA Astrophysics Data System (ADS)
Gao, Xiang; Feng, Xia; Li, Teng-Chao; Qu, Shixian; Wang, Xingang; Zhang, Hong
2017-05-01
Pinning of vortices by obstacles plays an important role in various systems. In the heart, anatomical reentry is created when a vortex, also known as the spiral wave, is pinned to an anatomical obstacle, leading to a class of physiologically very important arrhythmias. Previous analyses of its dynamics and instability provide fine estimates in some special circumstances, such as large obstacles or weak excitabilities. Here, to expand theoretical analyses to all circumstances, we propose a general theory whose results quantitatively agree with direct numerical simulations. In particular, when obstacles are small and pinned spiral waves are destabilized, an accurate explanation of the instability in two-dimensional media is provided by the usage of a mapping rule and dimension reduction. The implications of our results are to better understand the mechanism of arrhythmia and thus improve its early prevention.
Assessment of a simple obstacle detection device for the visually impaired.
Lee, Cheng-Lung; Chen, Chih-Yung; Sung, Peng-Cheng; Lu, Shih-Yi
2014-07-01
A simple obstacle detection device, based upon an automobile parking sensor, was assessed as a mobility aid for the visually impaired. A questionnaire survey for mobility needs was performed at the start of this study. After the detector was developed, five blindfolded sighted and 15 visually impaired participants were invited to conduct travel experiments under three test conditions: (1) using a white cane only, (2) using the obstacle detector only and (3) using both devices. A post-experiment interview regarding the usefulness of the obstacle detector for the visually impaired participants was performed. The results showed that the obstacle detector could augment mobility performance with the white cane. The obstacle detection device should be used in conjunction with the white cane to achieve the best mobility speed and body protection. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xu, C. Shan; Hayworth, Kenneth J.; Lu, Zhiyuan
Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) can automatically generate 3D images with superior z-axis resolution, yielding data that needs minimal image registration and related post-processing. Obstacles blocking wider adoption of FIB-SEM include slow imaging speed and lack of long-term system stability, which caps the maximum possible acquisition volume. Here, we present techniques that accelerate image acquisition while greatly improving FIB-SEM reliability, allowing the system to operate for months and generating continuously imaged volumes > 10 6 ?m 3 . These volumes are large enough for connectomics, where the excellent z resolution can help in tracing of small neuronal processesmore » and accelerate the tedious and time-consuming human proofreading effort. Even higher resolution can be achieved on smaller volumes. We present example data sets from mammalian neural tissue, Drosophila brain, and Chlamydomonas reinhardtii to illustrate the power of this novel high-resolution technique to address questions in both connectomics and cell biology.« less
Hudson, Phillip S; Woodcock, H Lee; Boresch, Stefan
2015-12-03
Carrying out free energy simulations (FES) using quantum mechanical (QM) Hamiltonians remains an attractive, albeit elusive goal. Renewed efforts in this area have focused on using "indirect" thermodynamic cycles to connect "low level" simulation results to "high level" free energies. The main obstacle to computing converged free energy results between molecular mechanical (MM) and QM (ΔA(MM→QM)), as recently demonstrated by us and others, is differences in the so-called "stiff" degrees of freedom (e.g., bond stretching) between the respective energy surfaces. Herein, we demonstrate that this problem can be efficiently circumvented using nonequilibrium work (NEW) techniques, i.e., Jarzynski's and Crooks' equations. Initial applications of computing ΔA(NEW)(MM→QM), for blocked amino acids alanine and serine as well as to generate butane's potentials of mean force via the indirect QM/MM FES method, showed marked improvement over traditional FES approaches.
Yan, Fu; Auerbach, David; Chai, Yi; Keller, Lena; Tu, Qiang; Hüttel, Stephan; Glemser, Amelie; Grab, Hanusch A; Bach, Thorsten; Zhang, Youming; Müller, Rolf
2018-04-25
Vioprolides are a promising class of anticancer and antifungal lead compounds produced by the myxobacterium Cystobacter violaceus Cb vi35. So far, nothing is known about their biosynthesis, including the origin of the unusual 4 methylazetidinecarboxylic acid (MAZ) moiety. We describe the vioprolide biosynthetic gene cluster and solve the production obstacle by expression in three heterologous hosts. Starting from unstable production in the wild type at single digit mg/L scale, we developed a stable host that eventually allowed for yields up to half a gram per liter in fermenters. Gene inactivations coupled with isotope feeding studies identified an S-adenosylmethionine (SAM) dependent enzyme and a methyltransferase as being responsible for the generation of the MAZ building block by a proposed mechanism unprecedented in bacteria. Furthermore, non-natural vioprolide derivatives were generated via rational genetic engineering. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
A robust signalling system for land mobile satellite services
NASA Technical Reports Server (NTRS)
Irish, Dale; Shmith, Gary; Hart, Nick; Wines, Marie
1989-01-01
Presented here is a signalling system optimized to ensure expedient call set-up for satellite telephony services in a land mobile environment. In a land mobile environment, the satellite to mobile link is subject to impairments from multipath and shadowing phenomena, which result in signal amplitude and phase variations. Multipath, caused by signal scattering and reflections, results in sufficient link margin to compensate for these variations. Direct signal attenuation caused by shadowing due to buildings and vegetation may result in attenuation values in excess of 10 dB and commonly up to 20 dB. It is not practical to provide a link with sufficient margin to enable communication when the signal is blocked. When a moving vehicle passes these obstacles, the link will experience rapid changes in signal strength due to shadowing. Using statistical models of attenuation as a function of distance travelled, a communication strategy has been defined for the land mobile environment.
Ice sculpture in the Martian outflow channels
NASA Technical Reports Server (NTRS)
Lucchitta, B. K.
1982-01-01
Viking Orbiter and terrestrial satellite images are examined at similar resolution to compare features of the Martian outflow channels with features produced by the movement of ice on earth, and many resemblances are found. These include the anastomoses, sinuosities, and U-shaped cross profiles of valleys; hanging valleys; linear scour marks on valley walls; grooves and ridges on valley floors; and the streamlining of bedrock highs. Attention is given to the question whether ice could have moved in the Martian environment. It is envisaged that springs or small catastrophic outbursts discharged fluids from structural outlets or chaotic terrains. These fluids built icings that may have grown into substantial masses and eventually flowed like glaciers down preexisting valleys. An alternative is that the fluids formed rivers or floods that in turn formed ice jams and consolidated into icy masses in places where obstacles blocked their flow.
Ibogaine in the treatment of substance dependence.
Brown, Thomas Kingsley
2013-03-01
Ibogaine is a psychoactive alkaloid derived from Tabernanthe iboga, a plant used in initiatory rituals in West Central Africa. Largely because of ibogaine's status as a Schedule I substance in the U.S., the development of ibogaine's use in the treatment of drug addiction took place outside conventional clinical and medical settings. This article reviews the history of ibogaine's use in the treatment of drug addiction, and discusses progress made towards, and obstacles blocking, the establishment of controlled clinical trials of ibogaine's efficacy. Preclinical research has generally supported anecdotal claims that ibogaine attenuates withdrawal symptoms and reduces drug cravings. Concerns about ibogaine's safety, as well as a dearth of solid data from human studies, have hampered progress in its development as an approved medication. This article outlines major findings from preclinical studies, discusses concerns about ibogaine's safety, and details previous and ongoing research on ibogaine's use as an anti-addictive treatment for humans.
Megasupramolecules for safer, cleaner fuel by end association of long telechelic polymers
NASA Astrophysics Data System (ADS)
Wei, Ming-Hsin; Li, Boyu; David, R. L. Ameri; Jones, Simon C.; Sarohia, Virendra; Schmitigal, Joel A.; Kornfield, Julia A.
2015-10-01
We used statistical mechanics to design polymers that defy conventional wisdom by self-assembling into “megasupramolecules” (≥5000 kg/mol) at low concentration (≤0.3 weight percent). Theoretical treatment of the distribution of individual subunits—end-functional polymers—among cyclic and linear supramolecules (ring-chain equilibrium) predicts that megasupramolecules can form at low total polymer concentration if, and only if, the backbones are long (>400 kg/mol) and end-association strength is optimal. Viscometry and scattering measurements of long telechelic polymers having polycyclooctadiene backbones and acid or amine end groups verify the formation of megasupramolecules. They control misting and reduce drag in the same manner as ultralong covalent polymers. With individual building blocks short enough to avoid hydrodynamic chain scission (weight-average molecular weights of 400 to 1000 kg/mol) and reversible linkages that protect covalent bonds, these megasupramolecules overcome the obstacles of shear degradation and engine incompatibility.
Carrillo, Mauricio; Que, Ulices; González, José A
2016-12-01
The present work investigates the application of artificial neural networks (ANNs) to estimate the Reynolds (Re) number for flows around a cylinder. The data required to train the ANN was generated with our own implementation of a lattice Boltzmann method (LBM) code performing simulations of a two-dimensional flow around a cylinder. As results of the simulations, we obtain the velocity field (v[over ⃗]) and the vorticity (∇[over ⃗]×v[over ⃗]) of the fluid for 120 different values of Re measured at different distances from the obstacle and use them to teach the ANN to predict the Re. The results predicted by the networks show good accuracy with errors of less than 4% in all the studied cases. One of the possible applications of this method is the development of an efficient tool to characterize a blocked flowing pipe.
Berlin, M A; Anand, Sheila
2014-01-01
This paper presents Direction based Hazard Routing Protocol (DHRP) for disseminating information about fixed road hazards such as road blocks, tree fall, boulders on road, snow pile up, landslide, road maintenance work and other obstacles to the vehicles approaching the hazardous location. The proposed work focuses on dissemination of hazard messages on highways with sparse traffic. The vehicle coming across the hazard would report the presence of the hazard. It is proposed to use Road Side fixed infrastructure Units for reliable and timely delivery of hazard messages to vehicles. The vehicles can then take appropriate safety action to avoid the hazardous location. The proposed protocol has been implemented and tested using SUMO simulator to generate road traffic and NS 2.33 network simulator to analyze the performance of DHRP. The performance of the proposed protocol was also compared with simple flooding protocol and the results are presented.
Unrecognized "AIDS" in Monkeys, 1969-1980: Explanations and Implications.
Hammett, Theodore M; Bronson, Roderick T
2016-06-01
AIDS was recognized in humans in 1981 and a simian form was described in the years 1983 to 1985. However, beginning in the late 1960s, outbreaks of opportunistic infections of AIDS were seen in monkeys in the United States. This apparent syndrome went unrecognized at the time. We have assembled those early cases in monkeys and offer reasons why they did not result in earlier recognition of simian or human AIDS, including weaknesses in understanding disease mechanisms, absence of evidence of human retroviruses, and a climate of opinion that devalued investigation of infectious disease and immunologic origins of disease. The "epistemological obstacle" explains important elements of this history in that misconceptions blocked understanding of the dependent relationship among viral infection, immunodeficiency, and opportunistic diseases. Had clearer understanding of the evidence from monkeys allowed human AIDS to be recognized earlier, life-saving prevention and treatment interventions might have been implemented sooner.
The influence of capitalism on the production of knowledge in nursing.
Lino, Monica Motta; Backes, Vânia Marli Schubert; Costa, Maria Arminda da Silva Mendes Carneiro da; Martins, Maria Manuela Ferreira Pereira da Silva; Lino, Murielk Motta
2017-06-26
To understand the capitalist influence over the production of nursing knowledge according to Brazilian and Portuguese researchers. Descriptive, exploratory, and qualitative research, with 17 research nurses selected using the snowball technique. Data were collected from October 2011 to November 2012 in Brazil and Portugal, by means of semi-structured interviews. We analysed the content of the interviews and produced inferences based in the theoretical assumptions of Gaston Bachelard and the notion of an epistemological obstacle. The results were organised into three categories: Blocks to creativity/innovation and the practice of repetition; Overestimation of the quantitative; and Resistance to rupture. It is necessary to create new ways of assessing scientific literature from a qualitative perspective that allows room for creativity, professional development, and critical and reflective thinking. Solidarity is perceived as an alternative to overcoming the problems caused by the capitalist way of producing knowledge.
Enhanced FIB-SEM systems for large-volume 3D imaging.
Xu, C Shan; Hayworth, Kenneth J; Lu, Zhiyuan; Grob, Patricia; Hassan, Ahmed M; García-Cerdán, José G; Niyogi, Krishna K; Nogales, Eva; Weinberg, Richard J; Hess, Harald F
2017-05-13
Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) can automatically generate 3D images with superior z-axis resolution, yielding data that needs minimal image registration and related post-processing. Obstacles blocking wider adoption of FIB-SEM include slow imaging speed and lack of long-term system stability, which caps the maximum possible acquisition volume. Here, we present techniques that accelerate image acquisition while greatly improving FIB-SEM reliability, allowing the system to operate for months and generating continuously imaged volumes > 10 6 µm 3 . These volumes are large enough for connectomics, where the excellent z resolution can help in tracing of small neuronal processes and accelerate the tedious and time-consuming human proofreading effort. Even higher resolution can be achieved on smaller volumes. We present example data sets from mammalian neural tissue, Drosophila brain, and Chlamydomonas reinhardtii to illustrate the power of this novel high-resolution technique to address questions in both connectomics and cell biology.
Elani, Yuval
2016-06-15
The quest to construct artificial cells from the bottom-up using simple building blocks has received much attention over recent decades and is one of the grand challenges in synthetic biology. Cell mimics that are encapsulated by lipid membranes are a particularly powerful class of artificial cells due to their biocompatibility and the ability to reconstitute biological machinery within them. One of the key obstacles in the field centres on the following: how can membrane-based artificial cells be generated in a controlled way and in high-throughput? In particular, how can they be constructed to have precisely defined parameters including size, biomolecular composition and spatial organization? Microfluidic generation strategies have proved instrumental in addressing these questions. This article will outline some of the major principles underpinning membrane-based artificial cells and their construction using microfluidics, and will detail some recent landmarks that have been achieved. © 2016 The Author(s).
Passive detection of subpixel obstacles for flight safety
NASA Astrophysics Data System (ADS)
Nixon, Matthew D.; Loveland, Rohan C.
2001-12-01
Military aircraft fly below 100 ft. above ground level in support of their missions. These aircraft include fixed and rotary wing and may be manned or unmanned. Flying at these low altitudes presents a safety hazard to the aircrew and aircraft, due to the occurrences of obstacles within the aircraft's flight path. The pilot must rely on eyesight and in some cases, infrared sensors to see obstacles. Many conditions can exacerbate visibility creating a situation in which obstacles are essentially invisible, creating a safety hazard, even to an alerted aircrew. Numerous catastrophic accidents have occurred in which aircraft have collided with undetected obstacles. Accidents of this type continue to be a problem for low flying military and commercial aircraft. Unmanned Aerial Vehicles (UAVs) have the same problem, whether operating autonomously or under control of a ground operator. Boeing-SVS has designed a passive, small, low- cost (under $100k) gimbaled, infrared imaging based system with advanced obstacle detection algorithms. Obstacles are detected in the infrared band, and linear features are analyzed by innovative cellular automata based software. These algorithms perform detection and location of sub-pixel linear features. The detection of the obstacles is performed on a frame by frame basis, in real time. Processed images are presented to the aircrew on their display as color enhanced features. The system has been designed such that the detected obstacles are displayed to the aircrew in sufficient time to react and maneuver the aircraft to safety. A patent for this system is on file with the US patent office, and all material herein should be treated accordingly.
Hsu, Wei-Chun; Liu, Ming-Wei; Lu, Tung-Wu
2016-03-01
People with type II diabetes mellitus (DM) are at a high risk of falling especially during more challenging locomotor tasks such as obstacle-crossing. The current study aimed to identify the risk factors for tripping in these patients during trailing-limb obstacle-crossing. Fourteen patients with type II DM with or without mild peripheral neuropathy (PN) and 14 healthy controls walked and crossed obstacles of three different heights while their motion data were measured using a motion capture system and two forceplates. The DM group was found to cross obstacles with significantly reduced trailing toe clearance (p<0.05), increasing the probability of the foot hitting the obstacle, and thus the risk of tripping. This altered end-point control was associated with significantly reduced knee flexion and hip adduction of the trailing swing limb (p<0.05), as well as significantly increased ankle plantarflexor moments in the leading stance limb (p<0.05). Therefore, reduced knee flexion and hip adduction of the swing limb are identified as risk factors for tripping during obstacle-crossing. Increased mechanical demands on the ankle plantarflexors suggest that weakness of these muscles may further reduce the already compromised performance of obstacle-crossing in these patients. The current results showed that obstacle-crossing can be used to detect gait deviations and to identify the associated risk of tripping in patients with type II DM without or at an early stage of PN. Copyright © 2016 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Hall, Brendan; Driscoll, Kevin; Schweiker, Kevin; Dutertre, Bruno
2013-01-01
Within distributed fault-tolerant systems the term force-fight is colloquially used to describe the level of command disagreement present at redundant actuation interfaces. This report details an investigation of force-fight using three distributed system case-study architectures. Each case study architecture is abstracted and formally modeled using the Symbolic Analysis Laboratory (SAL) tool chain from the Stanford Research Institute (SRI). We use the formal SAL models to produce k-induction based proofs of a bounded actuation agreement property. We also present a mathematically derived bound of redundant actuation agreement for sine-wave stimulus. The report documents our experiences and lessons learned developing the formal models and the associated proofs.
[Plants supporting the fight against the symptoms of menopause].
Gryszczyńska, Agnieszka; Gryszczyńska, Bogna; Opala, Bogna; Łowicki, Zdzisław
2013-01-01
The tradition of the use of plants resources in the fight against many diseases dates back to antiquity. Herbal medicine is used in the fight against less severe, as well as serious diseases. In view of the serious consequences of the use of hormone replacement therapy (HRT) to combat the symptoms of menopause are increasingly used plant medicines. According to the Women's Health Initiative (WHI) reported, their use is becoming more and more popular. An important advantage of this therapy is to prevent such the development of breast cancer, which is often a side effect of HRT. Therefore, this article also presents the most commonly used plants that help counteract the adverse symptoms of menopause.
Serotonin and aggressive motivation in crustaceans: altering the decision to retreat.
Huber, R; Smith, K; Delago, A; Isaksson, K; Kravitz, E A
1997-05-27
In crustaceans, as in most animal species, the amine serotonin has been suggested to serve important roles in aggression. Here we show that injection of serotonin into the hemolymph of subordinate, freely moving animals results in a renewed willingness of these animals to engage the dominants in further agonistic encounters. By multivariate statistical analysis, we demonstrate that this reversal results principally from a reduction in the likelihood of retreat and an increase in the duration of fighting. Serotonin infusion does not alter other aspects of fighting behavior, including which animal initiates an encounter, how quickly fighting escalates, or which animal eventually retreats. Preliminary studies suggest that serotonin uptake plays an important role in this behavioral reversal.
[The fight against venereal diseases in different political systems].
Scholz, A
2003-07-01
The fight against venereal diseases (VD) has often been influenced by the prevailing political and social conditions. At the end of 19th century the increase of VD demanded new strategies. In 1902 the German Society for the Control of VD was founded in Berlin. It was then followed by the foundation of the International Society against VD in Brussels in 1899. In the German empire and during the Nazi regime, authoritarian structures dominated the strategies against VD. The individual had to submit the interests of the society. Sociopolitical aspects influenced the discussions in the fight against VD during the Weimar republic. In 1927 the new laws to control VD met liberal demands.
NASA Astrophysics Data System (ADS)
Parvin, Salma; Sultana, Aysha
2017-06-01
The influence of High Intensity Focused Ultrasound (HIFU) on the obstacle through blood vessel is studied numerically. A three-dimensional acoustics-thermal-fluid coupling model is employed to compute the temperature field around the obstacle through blood vessel. The model construction is based on the linear Westervelt and conjugate heat transfer equations for the obstacle through blood vessel. The system of equations is solved using Finite Element Method (FEM). We found from this three-dimensional numerical study that the rate of heat transfer is increasing from the obstacle and both the convective cooling and acoustic streaming can considerably change the temperature field.
Obstacle Characterization in a Geocrowdsourced Accessibility System
NASA Astrophysics Data System (ADS)
Qin, H.; Aburizaiza, A. O.; Rice, R. M.; Paez, F.; Rice, M. T.
2015-08-01
Transitory obstacles - random, short-lived and unpredictable objects - are difficult to capture in any traditional mapping system, yet they have significant negative impacts on the accessibility of mobility- and visually-impaired individuals. These transitory obstacles include sidewalk obstructions, construction detours, and poor surface conditions. To identify these obstacles and assist the navigation of mobility- and visually- impaired individuals, crowdsourced mapping applications have been developed to harvest and analyze the volunteered obstacles reports from local students, faculty, staff, and residents. In this paper, we introduce a training program designed and implemented for recruiting and motivating contributors to participate in our geocrowdsourced accessibility system, and explore the quality of geocrowdsourced data with a comparative analysis methodology.
On the debate about teleology in biology: the notion of "teleological obstacle".
Ribeiro, Manuel Gustavo Leitão; Larentis, Ariane Leites; Caldas, Lúcio Ayres; Garcia, Tomás Coelho; Terra, Letícia Labati; Herbst, Marcelo Hawrylak; Almeida, Rodrigo Volcan
2015-12-01
Among the epistemological obstacles described by Gaston Bachelard, we contend that unitary and pragmatic knowledge is correlated to the teleological categories of Ernst Mayr and is the basis for prevailing debate on the notion of "function" in biology. Given the proximity of the aspects highlighted by these authors, we propose to associate the role of teleological thinking in biology and the notion of unitary and pragmatic knowledge as an obstacle to scientific knowledge. Thus, teleological thinking persists acting as an epistemological obstacle in biology, according to Bachelardian terminology. Our investigation led us to formulate the "teleological obstacle," which we consider important for the future of biology and possibly other sciences.
Smart walking stick for blind people: an application of 3D printer
NASA Astrophysics Data System (ADS)
Ikbal, Md. Allama; Rahman, Faidur; Ali, Md. Ripon; Kabir, M. Hasnat; Furukawa, Hidemitsu
2017-04-01
A prototype of the smart walking stick has been designed and characterized for the people who are visually impaired. In this study, it was considered that the proposed system will alert visuallyimpaired people over the obstacles which are in front of blind people as well as the obstacles of the street such as a manhole, when the blind people are walking in the street. The proposed system was designed in two stages, i.e. hardware and software which makes the system as a complete prototype. Three ultrasonic sonar sensors were used to detect in front obstacle and street surface obstacle such as manhole. Basically the sensor transmits an electromagnetic wave which travels toward the obstacle and back to the sensor receiver. The distance between the sensor and the obstacle is calculated from the received signal. The calculated distance value is compared with the pre-defined value and determines whether the obstacle is present or not. The 3D CAD software was used to design the sensor holder. An Up-Mini 3D printer was used to print the sensor holders which were mounted on the walking stick. Therefore, the sensors were fixed in the right position. Another sensor was used for the detecting the water on the walking street. The performance for detecting the obstacles and water indicate the merit of smart walking stick.
An assessment of auditory-guided locomotion in an obstacle circumvention task.
Kolarik, Andrew J; Scarfe, Amy C; Moore, Brian C J; Pardhan, Shahina
2016-06-01
This study investigated how effectively audition can be used to guide navigation around an obstacle. Ten blindfolded normally sighted participants navigated around a 0.6 × 2 m obstacle while producing self-generated mouth click sounds. Objective movement performance was measured using a Vicon motion capture system. Performance with full vision without generating sound was used as a baseline for comparison. The obstacle's location was varied randomly from trial to trial: it was either straight ahead or 25 cm to the left or right relative to the participant. Although audition provided sufficient information to detect the obstacle and guide participants around it without collision in the majority of trials, buffer space (clearance between the shoulder and obstacle), overall movement times, and number of velocity corrections were significantly (p < 0.05) greater with auditory guidance than visual guidance. Collisions sometime occurred under auditory guidance, suggesting that audition did not always provide an accurate estimate of the space between the participant and obstacle. Unlike visual guidance, participants did not always walk around the side that afforded the most space during auditory guidance. Mean buffer space was 1.8 times higher under auditory than under visual guidance. Results suggest that sound can be used to generate buffer space when vision is unavailable, allowing navigation around an obstacle without collision in the majority of trials.
Through the eyes of a bird: modelling visually guided obstacle flight
Lin, Huai-Ti; Ros, Ivo G.; Biewener, Andrew A.
2014-01-01
Various flight navigation strategies for birds have been identified at the large spatial scales of migratory and homing behaviours. However, relatively little is known about close-range obstacle negotiation through cluttered environments. To examine obstacle flight guidance, we tracked pigeons (Columba livia) flying through an artificial forest of vertical poles. Interestingly, pigeons adjusted their flight path only approximately 1.5 m from the forest entry, suggesting a reactive mode of path planning. Combining flight trajectories with obstacle pole positions, we reconstructed the visual experience of the pigeons throughout obstacle flights. Assuming proportional–derivative control with a constant delay, we searched the relevant parameter space of steering gains and visuomotor delays that best explained the observed steering. We found that a pigeon's steering resembles proportional control driven by the error angle between the flight direction and the desired opening, or gap, between obstacles. Using this pigeon steering controller, we simulated obstacle flights and showed that pigeons do not simply steer to the nearest opening in the direction of flight or destination. Pigeons bias their flight direction towards larger visual gaps when making fast steering decisions. The proposed behavioural modelling method converts the obstacle avoidance behaviour into a (piecewise) target-aiming behaviour, which is better defined and understood. This study demonstrates how such an approach decomposes open-loop free-flight behaviours into components that can be independently evaluated. PMID:24812052
Through the eyes of a bird: modelling visually guided obstacle flight.
Lin, Huai-Ti; Ros, Ivo G; Biewener, Andrew A
2014-07-06
Various flight navigation strategies for birds have been identified at the large spatial scales of migratory and homing behaviours. However, relatively little is known about close-range obstacle negotiation through cluttered environments. To examine obstacle flight guidance, we tracked pigeons (Columba livia) flying through an artificial forest of vertical poles. Interestingly, pigeons adjusted their flight path only approximately 1.5 m from the forest entry, suggesting a reactive mode of path planning. Combining flight trajectories with obstacle pole positions, we reconstructed the visual experience of the pigeons throughout obstacle flights. Assuming proportional-derivative control with a constant delay, we searched the relevant parameter space of steering gains and visuomotor delays that best explained the observed steering. We found that a pigeon's steering resembles proportional control driven by the error angle between the flight direction and the desired opening, or gap, between obstacles. Using this pigeon steering controller, we simulated obstacle flights and showed that pigeons do not simply steer to the nearest opening in the direction of flight or destination. Pigeons bias their flight direction towards larger visual gaps when making fast steering decisions. The proposed behavioural modelling method converts the obstacle avoidance behaviour into a (piecewise) target-aiming behaviour, which is better defined and understood. This study demonstrates how such an approach decomposes open-loop free-flight behaviours into components that can be independently evaluated.
Managing Our Environment, A Report on Ways Agricultural Research Fights Pollution.
ERIC Educational Resources Information Center
Department of Agriculture, Washington, DC.
A report on the ways agricultural research attempts to fight pollution is presented in this series of articles covering some of the major challenges facing scientists and regulatory officials working in agricultural research. Improved resource management is stressed with the use of advanced technologies as the avenue to solving environmental…
Parental Rights and Release Authorizations
ERIC Educational Resources Information Center
McGinnis, Michelle H.; Getskow, Veronica; Dicker, Brian S.
2012-01-01
Potentially difficult and dangerous situations can arise when an early childhood program is faced with parental rights and child custody issues. This is particularly true when the parents are engaged in a fight. Nothing is as visceral as the fight over a child, and even the best of people can become deceitful or quite villainous. School owners…
A Superintendent's Manifesto: School Wellness and Personal Health
ERIC Educational Resources Information Center
Carr-Lambert, Marsha L.
2010-01-01
As superintendent, the author works diligently to meet the demands by the West Virginia legislature, catalyzed by the aggressive role of West Virginia's First Lady Gayle Manchin, to fight child obesity. Recently, the state department of education agreed to enter the fight to curb the serious obesity and health problems among the children in the…
Juanita Fights the School Board.
ERIC Educational Resources Information Center
Velasquez, Gloria
This book relates the fictional story of Juanita Chavez, a Mexican-American teenager who unjustly faces expulsion from school after fighting with a White student who was spreading rumors about her family. Juanita knows that if she is expelled this will greatly disappoint her parents and shatter her dream of becoming the first one in her family to…
3 CFR 8344 - Proclamation 8344 of February 2, 2009. American Heart Month, 2009
Code of Federal Regulations, 2010 CFR
2010-01-01
... ongoing fight against cardiovascular disease, the Congress, by Joint Resolution approved December 30, 1963... fighting cardiovascular disease. IN WITNESS WHEREOF, I have hereunto set my hand this second day of... Proclamation Together, we can turn the tide on the number one killer of American women and men. Heart disease...
Fighting for Life in the Academy: Solutions to Gender Relationships from a Historical View.
ERIC Educational Resources Information Center
Weeks, Dennis L.
Misunderstandings across communication situations frequently occur due to gender differences in communication styles, differences in either meanings or values attached to the linguistic symbols used to convey a message. An analysis of communication in the classroom based on Walter J. Ong's educational history, "Fighting for Life Contest,…
Baché, David
2011-11-01
Kiné Sow is a home caregiver in the Senegalese village of Ndienné. With no initial connection with the medical world, she has been trained to fight against malaria. She carries out quick diagnostic tests and hands out medicines. A unique system set up by Dakar to fight against the disease in rural areas.
2014-06-13
Squadron ( BFV /HMMWV, Current) .................................................. 93 Description...Evaluation Criteria ........................................................ 106 Comparison to Validation Criteria: ABCT Cavalry Squadron ( BFV /HMMWV...Brigade Combat Team BFV Bradley Fighting Vehicle BRT Brigade Reconnaissance Troop CAB Combined Arms Battalion CFV Cavalry Fighting Vehicle FM
Chinese American Students Fight for Their Rights
ERIC Educational Resources Information Center
Wang, Yuxiang; Phillion, JoAnn
2007-01-01
Parental and community involvement play a key role in the Chinese American students' fight for their rights. In order to understand the reasons behind the parental and community support of Chinese students, a survey was conducted among Chinese parents to assess what they know about language loss, power, knowledge, and democracy. The results…
29 CFR 1910.159 - Automatic sprinkler systems.
Code of Federal Regulations, 2010 CFR
2010-07-01
... supply is out of service, except for systems of 20 or fewer sprinklers. (5) Hose connections for fire fighting use. The employer may attach hose connections for fire fighting use to wet pipe sprinkler systems... 29 Labor 5 2010-07-01 2010-07-01 false Automatic sprinkler systems. 1910.159 Section 1910.159...
29 CFR 1910.159 - Automatic sprinkler systems.
Code of Federal Regulations, 2013 CFR
2013-07-01
... supply is out of service, except for systems of 20 or fewer sprinklers. (5) Hose connections for fire fighting use. The employer may attach hose connections for fire fighting use to wet pipe sprinkler systems... 29 Labor 5 2013-07-01 2013-07-01 false Automatic sprinkler systems. 1910.159 Section 1910.159...
29 CFR 1910.159 - Automatic sprinkler systems.
Code of Federal Regulations, 2014 CFR
2014-07-01
... supply is out of service, except for systems of 20 or fewer sprinklers. (5) Hose connections for fire fighting use. The employer may attach hose connections for fire fighting use to wet pipe sprinkler systems... 29 Labor 5 2014-07-01 2014-07-01 false Automatic sprinkler systems. 1910.159 Section 1910.159...
29 CFR 1910.159 - Automatic sprinkler systems.
Code of Federal Regulations, 2012 CFR
2012-07-01
... supply is out of service, except for systems of 20 or fewer sprinklers. (5) Hose connections for fire fighting use. The employer may attach hose connections for fire fighting use to wet pipe sprinkler systems... 29 Labor 5 2012-07-01 2012-07-01 false Automatic sprinkler systems. 1910.159 Section 1910.159...
29 CFR 1910.159 - Automatic sprinkler systems.
Code of Federal Regulations, 2011 CFR
2011-07-01
... supply is out of service, except for systems of 20 or fewer sprinklers. (5) Hose connections for fire fighting use. The employer may attach hose connections for fire fighting use to wet pipe sprinkler systems... 29 Labor 5 2011-07-01 2011-07-01 false Automatic sprinkler systems. 1910.159 Section 1910.159...
Domestic Terrorism: Fighting the Local Threat with Local Enforcement
2013-03-01
In the game of fighting against a terrorism plot, waiting for an indication of a crime may be too late, the argument ran. Law enforcement needed more...such has a beauty salon selling chemicals or an Internet café with computers that have a browsing history of radical websites, those establishments
Joe Louis as a Key Functionary: White Reactions toward a Black Champion.
ERIC Educational Resources Information Center
Evans, Art
1985-01-01
Investigates White Americans' responses toward Joe Louis, the Black champion. Focuses on the Louis-Schmeling heavyweight title fight of 1938 as exemplifying Louis' role as a key functionary for the American system. Argues that Louis's achieved status as the American representative fighting against Nazism did not negate Whites' negative perception…
The War on Public Education: Agonist Democracy and the Fight for Schools as Public Things
ERIC Educational Resources Information Center
Knight, Kathleen Abowitz
2018-01-01
Agonistic critiques of democratic theory conceptualize democracy as a site of conflict and struggle; as the fight against privatization escalates, these critiques become more relevant for educational governance. Public education governance has, in addition, increasingly been the site of conflicts between federal, state and local levels, as…
U.S. Navy Shipyards. An Evaluation of Workload- and Workforce-Management Practices
2008-01-01
7 million man-hours (875,000 man-days). 2 Note that the Bradley Fighting Vehicle is maintained by the Red River Army Depot in Texarkana , Texas...and Workforce-Management Practices 103 The Red River Army Depot in Texarkana , Texas, supports the Bradley Fighting Vehicle as well as the Multiple
STS-47 crew participates in fire fighting exercises at JSC Fire Training Pit
NASA Technical Reports Server (NTRS)
1992-01-01
STS-47 Endeavour, Orbiter Vehicle (OV) 105, Mission Specialist (MS) N. Jan Davis (foreground) and MS and Payload Commander (PLC) Mark C. Lee, squinting and holding water hose, listen to instructions prior to participating in fire fighting exercises held at JSC's Fire Training Pit across from Gilruth Center Bldg 207.
The role of research in molecular entomology in the fight against malaria vectors.
della Torre, A; Arca, B; Favia, G; Petrarca, V; Coluzzi, M
2008-06-01
The text summarizes the principal current fields of investigation and the recent achievements of the research groups presently contributing to the Molecular Entomology Cluster of the Italian Malaria Network. Particular emphasis is given to the researches with a more direct impact on the fight against malaria vectors.
Doing and Feeling Research in Public: Queer Organizing for Public Education and Justice
ERIC Educational Resources Information Center
Meiners, Erica R.; Quinn, Therese M.
2010-01-01
Grounded in activism--fighting the implementation of Department of Defense-run schools in a public schools system; organizing to fight the largest national teacher education accreditation agency's removal of sexual orientation and social justice from its accreditation standards; and protesting a state's decision to hold a public meeting for…
The Fight for America's Schools: Grassroots Organizing in Education
ERIC Educational Resources Information Center
Ferman, Barbara, Ed.
2017-01-01
In "The Fight for America's Schools", Barbara Ferman brings together a diverse group of contributors to investigate how parents, communities, teachers, unions, and students are mobilizing to oppose market-based reforms in education. Drawing on a series of rich case studies, the book illustrates how disparate groups can forge new…
Attack on Academic Dishonesty: What "Lies" Ahead?
ERIC Educational Resources Information Center
Marshall, Leisa L.; Varnon, Anthony W.
2017-01-01
The purpose of this study is to apply corporate fraud fighting methods to develop a framework for fighting academic dishonesty in higher education. The evidence in the literature overwhelmingly supports the existence of academic dishonesty in higher education, with increases in admitted cheating over the past several decades and as many as 80…