On the Mechanism of D-Wave High TC Superconductivity by the Interplay of Jahn-Teller Physics and Mott Physics

NASA Astrophysics Data System (ADS)

Ushio, H.; Matsuno, S.; Kamimura, H.

2011-01-01

In the present paper we will discuss two important roles of the interplay of Jahn-Teller physics and Mott physics. One is the small Fermi surface. The "Fermi arcs" observed in ARPES should be one of the edges of small Fermi pockets, based on the Kamimura-Suwa model (K-S model). This prediction is consistent with ARPES results by Tanaka et al. Another is the mechanism of superconductivity in cuprates. This can be explained by the interplay of strong electron-phonon interactions and local AF order. It is shown that the characteristic phase difference of wave functions between up- and down-spin carriers in the presence of the local AF order leads to the superconducting gap of dx2-y2 symmetry even in the phonon-involved mechanism.

Providing Support to Inner-city Students and Teachers Through the Physics Van Inservice Institute

NASA Astrophysics Data System (ADS)

Sabella, Mel S.

2007-02-01

There are many programs for the professional development of high school physics teachers that have proven to be effective in preparing these teachers to conduct inquiry-based activities in the classroom. In this paper, we describe a small-scale professional development program called the Physics Van Inservice Institute. During the program, teachers are engaged in inquiry-based physics modules and are then able to borrow the equipment so that they can conduct the activities in their own classes.

"Physics Stories": How the Early Technologies of High Voltage and High Vacuum Led to "Modern Physics"

NASA Astrophysics Data System (ADS)

Greenslade, Thomas B.

2018-05-01

Some of you may remember the 1979 television series "Connections" that was written and narrated by James Burke, a British science writer. Burke's technique was to choose a number of seemingly unrelated ideas and show how they led to developments in science and technology. This is an enjoyable business, even if some of the connections seem to be stretched at times, and led to a book by Burke. In a number of talks that I have given over the years, I have made somewhat less fanciful connections that suggest how the technologies of high vacuum and high voltage led to what used to be called "modern physics." Today we might limit the "modern" era to the years from 1890 to 1920 that gave the first workable theories of small-scale physics.

Current Status of Women in Physics in Korea—and the New Physics Camp Initiative for High School Girls

NASA Astrophysics Data System (ADS)

Kim, Hyunjung; Song, Sanghoon; Park, Hyunjeong; Park, Jiseon; An, Jihye; Park, Joyoung; Yim, Haein; Song, Jeonghyeon; Yoon, Jin-Hee; Park, Youngah

2009-04-01

The Korean Physical Society (KPS) Women Committee has organized a series of the physics camps for high school girl students to give them an opportunity to work together and interact with professional physicists. Although the KPS Women Committee has successfully set the KPS's face toward women's issues, it still needs more systematic support for helping and promoting the activities of women physicists. We describe the physics camp initiative and present the current status of women in physics in Korea, comparing female ratios in undergraduate and graduate school and faculty for the last ten years (1998-2007). The employment rate for females is compared with that for males according to education level. The total number of female students in physics in Korea has increased; however, it is still a very small portion of females who stay in physics with professional positions.

Assaults, murders and walkers: The impact of violent crime on physical activity.

PubMed

Janke, Katharina; Propper, Carol; Shields, Michael A

2016-05-01

We investigate an underexplored externality of crime: the impact of violent crime on individuals' participation in walking. For many adults walking is the only regular physical activity. We use a sample of nearly 1 million people in 323 small areas in England between 2005 and 2011 matched to quarterly crime data at the small area level. Within area variation identifies the causal effect of local violent crime on walking and a difference-in-difference analysis of two high-profile crimes corroborates our results. We find a significant deterrent effect of violent crime on walking that translates into a drop in overall physical activity. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Bayesian performance metrics and small system integration in recent homeland security and defense applications

NASA Astrophysics Data System (ADS)

Jannson, Tomasz; Kostrzewski, Andrew; Patton, Edward; Pradhan, Ranjit; Shih, Min-Yi; Walter, Kevin; Savant, Gajendra; Shie, Rick; Forrester, Thomas

2010-04-01

In this paper, Bayesian inference is applied to performance metrics definition of the important class of recent Homeland Security and defense systems called binary sensors, including both (internal) system performance and (external) CONOPS. The medical analogy is used to define the PPV (Positive Predictive Value), the basic Bayesian metrics parameter of the binary sensors. Also, Small System Integration (SSI) is discussed in the context of recent Homeland Security and defense applications, emphasizing a highly multi-technological approach, within the broad range of clusters ("nexus") of electronics, optics, X-ray physics, γ-ray physics, and other disciplines.

Repeated sprints, high-intensity interval training, small-sided games: theory and application to field sports.

PubMed

Hoffmann, James J; Reed, Jacob P; Leiting, Keith; Chiang, Chieh-Ying; Stone, Michael H

2014-03-01

Due to the broad spectrum of physical characteristics necessary for success in field sports, numerous training modalities have been used develop physical preparedness. Sports like rugby, basketball, lacrosse, and others require athletes to be not only strong and powerful but also aerobically fit and able to recover from high-intensity intermittent exercise. This provides coaches and sport scientists with a complex range of variables to consider when developing training programs. This can often lead to confusion and the misuse of training modalities, particularly in the development of aerobic and anaerobic conditioning. This review outlines the benefits and general adaptations to 3 commonly used and effective conditioning methods: high-intensity interval training, repeated-sprint training, and small-sided games. The goals and outcomes of these training methods are discussed, and practical implementations strategies for coaches and sport scientists are provided.

Teachers' Manual: Using Teams-Games-Tournament (TGT) in the Physical Science Classroom.

ERIC Educational Resources Information Center

Hollifield, John H.; Leavey, Marshall B.

This teacher's manual provides general and specific guidelines for use of Teams-Games-Tournaments (TGT) Physical Science Curriculum materials at the junior high-middle school level. TGT is an innovative instructional model which focuses on the learning of basic skills, information, and concepts, rewarding students in small teams rather than at the…

Capitalizing on Community: the Small College Environment and the Development of Researchers

NASA Astrophysics Data System (ADS)

Stoneking, M. R.

2014-03-01

Liberal arts colleges constitute an important source of and training ground for future scientists. At Lawrence University, we take advantage of our small college environment to prepare physics students for research careers by complementing content acquisition with skill development and project experience distributed throughout the curriculum and with co-curricular elements that are tied to our close-knit supportive physics community. Small classes and frequent contact between physics majors and faculty members offer opportunities for regular and detailed feedback on the development of research relevant skills such as laboratory record-keeping, data analysis, electronic circuit design, computational programming, experimental design and modification, and scientific communication. Part of our approach is to balance collaborative group work on small projects (such as Arduino-based electronics projects and optical design challenges) with independent work (on, for example, advanced laboratory experimental extensions and senior capstone projects). Communal spaces and specialized facilities (experimental and computational) and active on-campus research programs attract eager students to the program, establish a community-based atmosphere, provide unique opportunities for the development of research aptitude, and offer opportunities for genuine contribution to a research program. Recently, we have also been encouraging innovativetendencies in physics majors through intentional efforts to develop personal characteristics, encouraging students to become more tolerant of ambiguity, risk-taking, initiative-seeking, and articulate. Indicators of the success of our approach include the roughly ten physics majors who graduate each year and our program's high ranking among institutions whose graduates go on to receive the Ph.D. in physics. Work supported in part by the National Science Foundation.

Match-derived relative pitch area changes the physical and team tactical performance of elite soccer players in small-sided soccer games.

PubMed

Olthof, Sigrid B H; Frencken, Wouter G P; Lemmink, Koen A P M

2018-07-01

Small-sided games (SSGs) are used in training sessions to prepare for full-sized matches. For the same number of players, smaller pitch sizes result in decreased physical performance and shorter interpersonal distances. A relative pitch area derived from the full-sized match results in larger pitch sizes and this may increase the fit between SSGs and full-sized matches. This study aimed to investigate SSGs with a traditional small pitch and a match-derived relative pitch area in youth elite soccer players. Four age categories (under-13, under-15, under-17 and under-19) played 4 vs. 4 plus goalkeepers on a small (40x30m, 120m 2 relative pitch area) and large pitch (68x47m, 320m 2 relative pitch area). The number of games per age category ranged 15-30. Positional data (LPM-system) were collected to determine physical (total distance covered, high intensity distance and number of sprints) and team tactical (inter-team distance, LPW-ratio, surface area, stretch indices, goalkeeper-defender distance) performance measures and tactical variability. On a large pitch, physical performance significantly increased, inter-team and intra-team distances were significantly larger and tactical variability of intra-team distance measures significantly increased. The match-derived relative pitch area is an important training manipulation and leads to changes in physical and tactical performance 4 vs. 4 plus goalkeepers.

PBX 9502 Gas Generation Progress Report FY17

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holmes, Matthew David; Erickson, Michael Andrew Englert

The self-ignition (“cookoff”) behavior of PBX 9502 depends on the dynamic evolution of gas permeability and physical damage in the material. The time-resolved measurement of product gas generation yields insight regarding the crucial properties that dominate cookoff behavior. We report on small-scale laboratory testing performed in FY17, in which small unconfined samples of PBX 9502 were heated in a small custom-built sealed pressure vessel to self-ignition. We recorded time-lapse video of the evolving physical changes in the sample, quasi-static long-duration pressure rise, then high-speed video and dynamic pressure rise of the cookoff event. We report the full pressure attained duringmore » the cookoff of a 1.02g sample in a free volume of 62.5 cm 3.« less

Thermal and hydrodynamic studies for micro-channel cooling for large area silicon sensors in high energy physics experiments

NASA Astrophysics Data System (ADS)

Flaschel, Nils; Ariza, Dario; Díez, Sergio; Gerboles, Marta; Gregor, Ingrid-Maria; Jorda, Xavier; Mas, Roser; Quirion, David; Tackmann, Kerstin; Ullan, Miguel

2017-08-01

Micro-channel cooling initially aiming at small-sized high-power integrated circuits is being transferred to the field of high energy physics. Today's prospects of micro-fabricating silicon opens a door to a more direct cooling of detector modules. The challenge in high energy physics is to save material in the detector construction and to cool large areas. In this paper, we are investigating micro-channel cooling as a candidate for a future cooling system for silicon detectors in a generic research and development approach. The work presented in this paper includes the production and the hydrodynamic and thermal testing of a micro-channel equipped prototype optimized to achieve a homogeneous flow distribution. Furthermore, the device was simulated using finite element methods.

Advances in understanding and parameterization of small-scale physical processes in the marine Arctic climate system: a review

NASA Astrophysics Data System (ADS)

Vihma, T.; Pirazzini, R.; Renfrew, I. A.; Sedlar, J.; Tjernström, M.; Nygård, T.; Fer, I.; Lüpkes, C.; Notz, D.; Weiss, J.; Marsan, D.; Cheng, B.; Birnbaum, G.; Gerland, S.; Chechin, D.; Gascard, J. C.

2013-12-01

The Arctic climate system includes numerous highly interactive small-scale physical processes in the atmosphere, sea ice, and ocean. During and since the International Polar Year 2007-2008, significant advances have been made in understanding these processes. Here these advances are reviewed, synthesized and discussed. In atmospheric physics, the primary advances have been in cloud physics, radiative transfer, mesoscale cyclones, coastal and fjordic processes, as well as in boundary-layer processes and surface fluxes. In sea ice and its snow cover, advances have been made in understanding of the surface albedo and its relationships with snow properties, the internal structure of sea ice, the heat and salt transfer in ice, the formation of super-imposed ice and snow ice, and the small-scale dynamics of sea ice. In the ocean, significant advances have been related to exchange processes at the ice-ocean interface, diapycnal mixing, tidal currents and diurnal resonance. Despite this recent progress, some of these small-scale physical processes are still not sufficiently understood: these include wave-turbulence interactions in the atmosphere and ocean, the exchange of heat and salt at the ice-ocean interface, and the mechanical weakening of sea ice. Many other processes are reasonably well understood as stand-alone processes but challenge is to understand their interactions with, and impacts and feedbacks on, other processes. Uncertainty in the parameterization of small-scale processes continues to be among the largest challenges facing climate modeling, and nowhere is this more true than in the Arctic. Further improvements in parameterization require new year-round field campaigns on the Arctic sea ice, closely combined with satellite remote sensing studies and numerical model experiments.

Developing an intervention to address physical activity barriers for African–American women in the deep south (USA)

PubMed Central

Pekmezi, Dori; Marcus, Bess; Meneses, Karen; Baskin, Monica L; Ard, Jamy D; Martin, Michelle Y; Adams, Natasia; Robinson, Cody; Demark-Wahnefried, Wendy

2013-01-01

Aim To address high rates of inactivity and related chronic diseases among African–American women. Materials & methods Eleven focus groups on physical activity barriers for African–American women in the deep south (USA) were conducted (n = 56). Feedback guided an intervention development process. The resulting Home-Based Individually Tailored Physical Activity Print intervention was vetted with the target population in a 1-month, single arm, pre–post test demonstration trial (n = 10). Results Retention was high (90%). Intent-to-treat analyses indicated increases in motivational readiness for physical activity (70% of sample) and physical activity (7-day Physical Activity Recall) from baseline (mean: 89.5 min/week, standard deviation: 61.17) to 1 month (mean: 155 min/week, standard deviation: 100.86). Small improvements in fitness (6-Min Walk Test), weight and psychosocial process measures were also found. Conclusion Preliminary findings show promise and call for future randomized controlled trials with larger samples to determine efficacy. Such low-cost, high-reach approaches to promoting physical activity have great potential for addressing health disparities and benefiting public health. PMID:23638785

Developing an intervention to address physical activity barriers for African-American women in the deep south (USA).

PubMed

Pekmezi, Dori; Marcus, Bess; Meneses, Karen; Baskin, Monica L; Ard, Jamy D; Martin, Michelle Y; Adams, Natasia; Robinson, Cody; Demark-Wahnefried, Wendy

2013-05-01

To address high rates of inactivity and related chronic diseases among African-American women. Eleven focus groups on physical activity barriers for African-American women in the deep south (USA) were conducted (n = 56). Feedback guided an intervention development process. The resulting Home-Based Individually Tailored Physical Activity Print intervention was vetted with the target population in a 1-month, single arm, pre-post test demonstration trial (n = 10). Retention was high (90%). Intent-to-treat analyses indicated increases in motivational readiness for physical activity (70% of sample) and physical activity (7-day Physical Activity Recall) from baseline (mean: 89.5 min/week, standard deviation: 61.17) to 1 month (mean: 155 min/week, standard deviation: 100.86). Small improvements in fitness (6-Min Walk Test), weight and psychosocial process measures were also found. Preliminary findings show promise and call for future randomized controlled trials with larger samples to determine efficacy. Such low-cost, high-reach approaches to promoting physical activity have great potential for addressing health disparities and benefiting public health.

The physical environment mediates male harm and its effect on selection in females.

PubMed

Yun, Li; Chen, Patrick J; Singh, Amardeep; Agrawal, Aneil F; Rundle, Howard D

2017-07-12

Recent experiments indicate that male preferential harassment of high-quality females reduces the variance in female fitness, thereby weakening natural selection through females and hampering adaptation and purging. We propose that this phenomenon, which results from a combination of male choice and male-induced harm, should be mediated by the physical environment in which intersexual interactions occur. Using Drosophila melanogaster , we examined intersexual interactions in small and simple (standard fly vials) versus slightly more realistic (small cages with spatial structure) environments. We show that in these more realistic environments, sexual interactions are less frequent, are no longer biased towards high-quality females, and that overall male harm is reduced. Next, we examine the selective advantage of high- over low-quality females while manipulating the opportunity for male choice. Male choice weakens the viability advantage of high-quality females in the simple environment, consistent with previous work, but strengthens selection on females in the more realistic environment. Laboratory studies in simple environments have strongly shaped our understanding of sexual conflict but may provide biased insight. Our results suggest that the physical environment plays a key role in the evolutionary consequences of sexual interactions and ultimately the alignment of natural and sexual selection. © 2017 The Author(s).

AMS with light nuclei at small accelerators

NASA Astrophysics Data System (ADS)

Stan-Sion, C.; Enachescu, M.

2017-06-01

AMS applications with lighter nuclei are presented. It will be shown how Carbon-14, Boron-10, Beryllium-10, and Tritium-3 can be used to provide valuable information in forensic science, environmental physics, nuclear pollution, in material science and for diagnose of the plasma confinement in fusion reactors. Small accelerators are reliable, efficient and possess the highest ion beam transmissions that confer high precision in measurements.

Implementing ILDs and Assessment in Small-enrollment, Calculus-based Physics Classes -- Lessons, Observations and Open Questions

NASA Astrophysics Data System (ADS)

Mason-McCaffrey, Deborah

2011-04-01

At Salem State, we offer a Physics minor, but most of our teaching load is support courses for other science majors and a lab sequence which satisfies the University's core education requirement. In three years of using assessments and ILDs in small-enrollment calculus-based Physics classes, there has been a significant implementation learning curve, there are encouraging results, a few cautions, and still some open questions to report. ILDs can be highly effective teaching tools. They do require significant advance preparation as well as a safe environment for student participation. Motivating students to do their best on assessment pre- and post-tests can also be difficult. Strategies for motivating assessment performance, experiments using clickers to encourage participation in ILDs, and modifying and developing home-grown ILDs are discussed.

Optimising technical skills and physical loading in small-sided basketball games.

PubMed

Klusemann, Markus J; Pyne, David B; Foster, Carl; Drinkwater, Eric J

2012-01-01

Differences in physiological, physical, and technical demands of small-sided basketball games related to the number of players, court size, and work-to-rest ratios are not well characterised. A controlled trial was conducted to compare the influence of number of players (2v2/4v4), court size (half/full court) and work-to-rest ratios (4x2.5 min/2x5 min) on the demands of small-sided games. Sixteen elite male and female junior players (aged 15-19 years) completed eight variations of a small-sided game in randomised order over a six-week period. Heart rate responses and rating of perceived exertion (RPE) were measured to assess the physiological load. Movement patterns and technical elements were assessed by video analysis. There were ∼60% more technical elements in 2v2 and ∼20% more in half court games. Heart rate (86 ± 4% & 83 ± 5% of maximum; mean ± SD) and RPE (8 ± 2 & 6 ± 2; scale 1-10) were moderately higher in 2v2 than 4v4 small-sided games, respectively. The 2v2 format elicited substantially more sprints (36 ±12%; mean ±90% confidence limits) and high intensity shuffling (75 ±17%) than 4v4. Full court games required substantially more jogging (9 ±6%) compared to half court games. Fewer players in small-sided basketball games substantially increases the technical, physiological and physical demands.

The efficacy of World Wide Web-mediated microcomputer-based laboratory activities in the high school physics classroom

NASA Astrophysics Data System (ADS)

Slykhuis, David A.

This research project examined the efficacy of an online microcomputer-based laboratory based (MBL) physics unit. One hundred and fifty physics students from five high schools in North Carolina were divided into online and classroom groups. The classroom group completed the MBL unit in small groups with assistance from their teachers. The online groups completed the MBL unit in small groups using a website designed for this project for guidance. Pre- and post-unit content specific tests and surveys were given. Statistical analysis of the content tests showed significant development of conceptual understanding by the online group over the course of the unit. There was not a significant difference between the classroom and online group with relation to the amount of conceptual understanding developed. Correlations with post-test achievement showed that pre-test scores and math background were the most significant correlates with success. Computer related variables, such as computer comfort and online access, were only mildly correlated with the online group. Students' views about the nature of physics were not well developed prior to the unit and did not significantly change over the course of the unit. Examination of the students' physics conceptions after instruction revealed common alternative conceptions such as confusing position and velocity variables and incorrect interpretations of graphical features such as slope.

Small Seed Black Hole Growth in Various Accretion Regimes

NASA Astrophysics Data System (ADS)

Gerling-Dunsmore, Hannalore J.; Hopkins, Philip F.

2016-03-01

Observational evidence indicates a population of super massive black holes (SMBHs) (~109 -1010M⊙) formed within 1 Gyr after the Big Bang. One proposed means of SMBH formation is accretion onto small seed black holes (BHs) (~ 100M⊙). However, the existence of SMBHs within 1 Gyr requires rapid growth, but conventional models of accretion fail to grow the seed BHs quickly enough. Super Eddington accretion (Ṁ >ṀEddington) may aid in improving growth efficiency. We study small seed BH growth via accretion in 3D, using the magneto-hydrodynamics+gravity code GIZMO. In particular, we consider a BH in a high density turbulent star-forming cloud, and ask whether or not the BH can capture sufficient gas to grow rapidly. We consider both Eddington-limited and super Eddington regimes, and resolve physics on scales from 0.1 pc to 1 kpc while including detailed models for stellar feedback physics, including stellar winds, supernovae, radiation pressure, and photo-ionization. We present results on the viability of different small seed BHs growing into SMBH candidates.

Anaphylaxis Imaging: Non-Invasive Measurement of Surface Body Temperature and Physical Activity in Small Animals

PubMed Central

Manzano-Szalai, Krisztina; Pali-Schöll, Isabella; Krishnamurthy, Durga; Stremnitzer, Caroline; Flaschberger, Ingo; Jensen-Jarolim, Erika

2016-01-01

In highly sensitized patients, the encounter with a specific allergen from food, insect stings or medications may rapidly induce systemic anaphylaxis with potentially lethal symptoms. Countless animal models of anaphylaxis, most often in BALB/c mice, were established to understand the pathophysiology and to prove the safety of different treatments. The most common symptoms during anaphylactic shock are drop of body temperature and reduced physical activity. To refine, improve and objectify the currently applied manual monitoring methods, we developed an imaging method for the automated, non-invasive measurement of the whole-body surface temperature and, at the same time, of the horizontal and vertical movement activity of small animals. We tested the anaphylaxis imaging in three in vivo allergy mouse models for i) milk allergy, ii) peanut allergy and iii) egg allergy. These proof-of-principle experiments suggest that the imaging technology represents a reliable non-invasive method for the objective monitoring of small animals during anaphylaxis over time. We propose that the method will be useful for monitoring diseases associated with both, changes in body temperature and in physical behaviour. PMID:26963393

``Physics with a Smile''-Explaining Phenomena with a Qualitative Problem-Solving Strategy

NASA Astrophysics Data System (ADS)

Mualem, Roni; Eylon, Bat-Sheva

2007-03-01

Various studies indicate that high school physics students and even college students majoring in physics have difficulties in qualitative understanding of basic concepts and principles of physics.1-5 For example, studies carried out with the Force Concept Inventory (FCI)1,6 illustrate that qualitative tasks are not easy to solve even at the college level. Consequently, "conceptual physics" courses have been designed to foster qualitative understanding, and advanced high school physics courses as well as introductory college-level courses strive to develop qualitative understanding. Many physics education researchers emphasize the importance of acquiring some qualitative understanding of basic concepts in physics as early as middle school or in the context of courses that offer "Physics First" in the ninth grade before biology or chemistry.7 This trend is consistent with the call to focus the science curriculum on a small number of basic concepts and ideas, and to instruct students in a more "meaningful way" leading to better understanding. Studies7-10 suggest that familiar everyday contexts (see Fig. 1) are useful in fostering qualitative understanding.

Passeport pour les deux infinis: an educational project in French

NASA Astrophysics Data System (ADS)

Arnaud, Nicolas; Descotes-Genon, Sébastien; Kerhoas-Cavata, Sophie; Paul, Jacques; Robert-Esil, Jean-Luc; Royole-Degieux, Perrine

2016-04-01

Passeport pour les deux infinis (;Passport for the two infinities;, in short Pass2i) is a French educational project aiming at promoting the physics of the infinitely small (particle physics) and of the infinitely big (cosmology & astrophysics) to high-school teachers and students. It is managed since 2009 by a small team of outreach experts (physicists and engineers) from the CNRS and the CEA. The Pass2i cornerstone is a reversible book - where each side explores one of the two infinities - and which is given for free to science high school teachers who request it, thanks to the support of French funding agencies. The Pass2i non-profit association wants to be a bridge between science and education: training sessions are organized for teachers, educational resources created and made available for download on the Pass2i website (http://www.passeport2i.fr).

Computational Design of Clusters for Catalysis

NASA Astrophysics Data System (ADS)

Jimenez-Izal, Elisa; Alexandrova, Anastassia N.

2018-04-01

When small clusters are studied in chemical physics or physical chemistry, one perhaps thinks of the fundamental aspects of cluster electronic structure, or precision spectroscopy in ultracold molecular beams. However, small clusters are also of interest in catalysis, where the cold ground state or an isolated cluster may not even be the right starting point. Instead, the big question is: What happens to cluster-based catalysts under real conditions of catalysis, such as high temperature and coverage with reagents? Myriads of metastable cluster states become accessible, the entire system is dynamic, and catalysis may be driven by rare sites present only under those conditions. Activity, selectivity, and stability are highly dependent on size, composition, shape, support, and environment. To probe and master cluster catalysis, sophisticated tools are being developed for precision synthesis, operando measurements, and multiscale modeling. This review intends to tell the messy story of clusters in catalysis.

Differences and changes in the physical characteristics of professional and amateur rugby union players.

PubMed

Smart, Daniel J; Hopkins, Will G; Gill, Nicholas D

2013-11-01

Numerous studies have highlighted differences between playing levels and positions in rugby union; however, few studies have investigated longitudinal progressions of body composition and physical performance. Between-player differences and within-player changes in body composition, strength, power, speed, and repeated sprint ability, from 1,161 New Zealand rugby union players from 2004 to 2007, were estimated using a mixed modeling procedure. Props had the highest mass, percent body fat, strength, and slowest speed times compared with the other positions, whereas outside backs had the fastest speed time and lowest percent body fat. For most measures, there were small-to-moderate differences (range, 1.1-14%) between players selected and not selected for provincial teams and small-to-large differences (range, 1.8-15%) between provincial and Super Rugby (professional) players. The faster 20-m sprint times in international compared with Super Rugby players was small in magnitude for both the forwards (1.9%) and backs (2.2%). The average annual improvements were small to moderate for strength (range, 2.1-15%) and small for repeated sprint ability within the lower playing levels (~1.5%). Small increases occurred in lower body strength (~7.0%) as players moved from Super Rugby to provincial competition. Small decreases in sprint time (~1.6%) and small increases in strength (~6.3%) occurred as players moved from Super Rugby to midyear international competition. The differences between levels in performance provide level-specific characteristics from Super Rugby and below, but international players may be selected because of greater skill and experience. Changes in physical performance between competitions may be a result of reduced training loads because of regular high-intensity matches and greater travel involved in the Super Rugby competition.

Introducing the USAYPT--Do Research in Your High School then Debate Your Results with Other Schools

ERIC Educational Resources Information Center

Oldaker, Bruce G.; Jacobs, Greg; Bibilashvili, Tengiz

2010-01-01

We introduce the USAYPT--the United States Association for Young Physicists Tournaments, Inc. Our motto is "Better teaching and learning by doing research in your high school." We believe that all high school teachers can improve their knowledge of physics by forming small groups that perform non-trivial--but not cutting edge--research. In order…

[Physical activity, dietary habits and plasma lipoproteins in young men and women].

PubMed

Malara, Marzena; Lutosławska, Grazyna

2010-01-01

There are studies suggesting that in young women strenuous physical activity and inadequate daily energy intake cause unfavorable changes in lipoprotein profile. However until know data concerning this issue are contradictory, possibly due to small number of participants. This study aimed at evaluation of lipoprotein profile in young men and women with different weekly physical activity together with their dietary habits. A total of 202 subjects volunteered to participate of the study--54 female and 56 male students of physical education and 46 female and 49 male students representing other specialization. Daily energy and macronutrient intakes were assessed using FOOD 2 computer program. Plasma TG, TC and HDL-C were assayed colorimetically using Randox commercial kits (Great Britain). It has been demonstrated that high physical activity adversely affects lipoprotein profile in young women characterized by higher TC and LDL-C in comparison with women with low physical activity and with men with high physical activity. The effect of high physical activity on plasma lipoproteins is equivocal. Active men are characterized by higher HDL, but also by higher frequency of unfavorable plasma TC and similar frequency of unfavorable plasma LDL-C C as compared with their less active counterparts. The mean daily energy intake in highly active men and women covered 82% and 72.2% recommended intake, respectively. It seems feasible that in both sexes high physical activity and inadequate energy intake brings about unfavorable changes in plasma lipoproteins.

Shot noise at high temperatures

NASA Astrophysics Data System (ADS)

Gutman, D. B.; Gefen, Yuval

2003-07-01

We consider the possibility of measuring nonequilibrium properties of the current correlation functions at high temperatures (and small bias). Through the example of the third cumulant of the current (S3) we demonstrate that odd-order correlation functions represent nonequilibrium physics even at small external bias and high temperatures. We calculate S3=y(eV/T)e2I for a quasi-one-dimensional diffusive constriction. We calculate the scaling function y in two regimes: when the scattering processes are purely elastic and when the inelastic electron-electron scattering is strong. In both cases we find that y interpolates between two constants. In the low- (high-) temperature limit y is strongly (weakly) enhanced (suppressed) by the electron-electron scattering.

Changes of the Electrical and Optical Character of Polyimide Films (and the Chemistry that Drives Them) Due to Exposure to High Energy GEO-like Electrons

DTIC Science & Technology

2015-10-18

developed models to fit this data and derive the bulk conductivity. [9-11, 19] After aging and measuring discharge rates we remove small pieces of...34Charge trapping in corona -charge polyethylene films," Journal of Physics D: Applied Physics, vol. 13, p. 1343, 1980. [20] R. Li, C. Li, S. He, M. Di

Relationship between diet and physical activity level in adolescents from post-grammar schools.

PubMed

Dmitruk, Agnieszka; Kunicka, Izabela; Popławska, Helena; Hołub, Wojciech

2016-01-01

Appropriate diet and physical activity are vital determinants of psychophysical development in children and adolescents. The aim of the study was to analyse an association between dietary habits and physical activity levels of adolescents from post-grammar schools. The study included 110 girls and 65 boys between 16 and 19 years of age from two post-grammar schools in Biała Podlaska in Poland. They were subjected to a diagnostic survey providing information on their diet (number of meals a day, their regularity, frequency of bread, dairy, meat, fish, sweet, fruit, vegetable and fast food consumption, preferred ways of food processing). Physical activity levels were determined with the International Physical Activity Questionnaire--Short Form (IPAQ-SF). Based on these data, the respondents were stratified to high, moderate and low physical activity groups. Due to small number of participants presenting with low physical activity levels, we did not include this group in further analyses. The significance of differences in the dietary habits of adolescents presenting with high and moderate physical activity levels was verified with the χ2 test. Most girls and boys presented with high levels of physical activity. However, we did not find an evident relationship between dietary habits and physical activity levels. Girls from high and moderate physical activity groups differed solely in terms of the number of daily meals, frequency of meat and sweet consumption, and significant intergroup differences observed among boys pertained to the frequencies of whole-wheat bread, meat and fast food consumption. The abovementioned food products were consumed more often by girls and boys presenting with high physical activity levels. The dietary mistakes observed in physically active adolescents from post-secondary schools justify intensification of their dietary education programs.

Theory and Modeling of High-Power Gyrotrons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nusinovich, Gregory Semeon

2016-04-29

This report summarized results of the work performed at the Institute for Research in Electronics and Applied Physics of the University of Maryland (College Park, MD) in the framework of the DOE Grant “Theory and Modeling of High-Power Gyrotrons”. The report covers the work performed in 2011-2014. The research work was performed in three directions: - possibilities of stable gyrotron operation in very high-order modes offering the output power exceeding 1 MW level in long-pulse/continuous-wave regimes, - effect of small imperfections in gyrotron fabrication and alignment on the gyrotron efficiency and operation, - some issues in physics of beam-wave interactionmore » in gyrotrons.« less

The Physics of a Gymnastics Flight Element

NASA Astrophysics Data System (ADS)

Contakos, Jonas; Carlton, Les G.; Thompson, Bruce; Suddaby, Rick

2009-09-01

From its inception, performance in the sport of gymnastics has relied on the laws of physics to create movement patterns and static postures that appear almost impossible. In general, gymnastics is physics in motion and can provide an ideal framework for studying basic human modeling techniques and physical principles. Using low-end technology and basic principles of physics, we analyzed a high-end gymnastics skill competed in by both men and women. The comprehensive goal of the examination is to scientifically understand how a skill of this magnitude is actually physically possible and what must a gymnast do to successfully complete the skill. The examination is divided into three sections, each of which is comprehensive enough to be a separate assignment or small group project.

Physics of Health Sciences

NASA Astrophysics Data System (ADS)

Baublitz, Millard; Goldberg, Bennett

A one-semester algebra-based physics course is being offered to Boston University students whose major fields of study are in allied health sciences: physical therapy, athletic training, and speech, language, and hearing sciences. The classroom instruction incorporates high-engagement learning techniques including worksheets, student response devices, small group discussions, and physics demonstrations instead of traditional lectures. The use of pre-session exercises and quizzes has been implemented. The course also requires weekly laboratory experiments in mechanics or electricity. We are using standard pre- and post-course concept inventories to compare this one-semester introductory physics course to ten years of pre- and post-course data collected on students in the same majors but who completed a two-semester course.

Active learning of introductory optics: real-time physics labs, interactive lecture demonstrations and magic

NASA Astrophysics Data System (ADS)

Sokoloff, David R.

2005-10-01

Widespread physics education research has shown that most introductory physics students have difficulty learning essential optics concepts - even in the best of traditional courses, and that well-designed active learning approaches can remedy this problem. This mini-workshop and the associated poster session will provide direct experience with methods for promoting students' active involvement in the learning process in lecture and laboratory. Participants will have hands-on experience with activities from RealTime Physics labs and Interactive Lecture Demonstrations - a learning strategy for large (and small) lectures, including specially designed Optics Magic Tricks. The poster will provide more details on these highly effective curricula.

Examination of Wildland Fire Spread at Small Scales Using Direct Numerical Simulations and High-Speed Laser Diagnostics

NASA Astrophysics Data System (ADS)

Wimer, N. T.; Mackoweicki, A. S.; Poludnenko, A. Y.; Hoffman, C.; Daily, J. W.; Rieker, G. B.; Hamlington, P.

2017-12-01

Results are presented from a joint computational and experimental research effort focused on understanding and characterizing wildland fire spread at small scales (roughly 1m-1mm) using direct numerical simulations (DNS) with chemical kinetics mechanisms that have been calibrated using data from high-speed laser diagnostics. The simulations are intended to directly resolve, with high physical accuracy, all small-scale fluid dynamic and chemical processes relevant to wildland fire spread. The high fidelity of the simulations is enabled by the calibration and validation of DNS sub-models using data from high-speed laser diagnostics. These diagnostics have the capability to measure temperature and chemical species concentrations, and are used here to characterize evaporation and pyrolysis processes in wildland fuels subjected to an external radiation source. The chemical kinetics code CHEMKIN-PRO is used to study and reduce complex reaction mechanisms for water removal, pyrolysis, and gas phase combustion during solid biomass burning. Simulations are then presented for a gaseous pool fire coupled with the resulting multi-step chemical reaction mechanisms, and the results are connected to the fundamental structure and spread of wildland fires. It is anticipated that the combined computational and experimental approach of this research effort will provide unprecedented access to information about chemical species, temperature, and turbulence during the entire pyrolysis, evaporation, ignition, and combustion process, thereby permitting more complete understanding of the physics that must be represented by coarse-scale numerical models of wildland fire spread.

Secondary analysis of teaching methods in introductory physics: A 50 k-student study

NASA Astrophysics Data System (ADS)

Von Korff, Joshua; Archibeque, Benjamin; Gomez, K. Alison; Heckendorf, Tyrel; McKagan, Sarah B.; Sayre, Eleanor C.; Schenk, Edward W.; Shepherd, Chase; Sorell, Lane

2016-12-01

Physics education researchers have developed many evidence-based instructional strategies to enhance conceptual learning of students in introductory physics courses. These strategies have historically been tested using assessments such as the Force Concept Inventory (FCI) and the Force and Motion Conceptual Evaluation (FMCE). We have performed a review and analysis of FCI and FMCE data published between 1995 and 2014. We confirm previous findings that interactive engagement teaching techniques are significantly more likely to produce high student learning gains than traditional lecture-based instruction. We also establish that interactive engagement instruction works in many settings, including those with students having a high and low level of prior knowledge, at liberal arts and research universities, and enrolled in both small and large classes.

The Physics Learning Program at UW-Madison: Strategies for Creating an Inclusive Learning Environment

NASA Astrophysics Data System (ADS)

Nossal, S. M.; Watson, L. E.; Jacob, A. T.; Reading, J. A.

2005-05-01

The Physics Learning Program at the University of Wisconsin-Madison provides a supportive learning environment for introductory physics students potentially at-risk for having academic trouble or for feeling isolated at the University. Physics is a gateway course for many undergraduate science majors such as biology, physics, geophysics, atmospheric science, and astronomy, and for pre-health professions. Many students struggle with their physics courses due to factors including large class sizes, isolation and lack of study partners, and/or lack of confidence in mathematical problem solving skills. Our students include those with learning disabilities, no high school physics, weak math backgrounds, and/or on academic probation. We also work with students who may be feeling isolated, such as students from historically underrepresented racial and ethnic groups, first generation college students, returning adults, international students, and students from small rural schools. Many of our students are also part of retention programs such as the TRIO program, the Academic Advancement Program, the McNair Scholars Program, and the McBurney Disability Resource Center. The Physics Learning Program's Peer Mentor Tutor program is run in conjunction with similar programs for chemistry and biochemistry at the University of Wisconsin. We will discuss strategies we use for creating an inclusive learning environment that engages students in their learning. Such strategies include small group instruction, ongoing training of the tutors, teaching problem solving skills, and creating a welcoming atmosphere.

Intraabdominal desmoplastic small round cell tumor: Report of a case and literature review.

PubMed

Koniari, Katerina; Mahera, Helen; Nikolaou, Marinos; Chatzis, Odysseas; Glezakou, Ourania; Magiasis, Vasilios; Kiratzis, Georgios

2011-01-01

Desmoplastic small round cell tumor is a rare malignancy with poor prognosis that predominantly affects young males. Its etiopathogenesis is still unknown and diagnosis can be achieved only by immunohistochemistry and cytogenetic studies. Due to our limited knowledge of the pathologic and clinical nature of this disease, there is no clear consensus regarding the optimal therapeutic procedures for treating this neoplasm. A high degree of care and improvements in diagnostic capabilities are required in order to identify this entity and avoid misdiagnosis. We report a new case of a 29-year-old male who proceeded to our Emergency Department complaining about non-specific abdominal pain. Physical examination revealed no abnormalities except for a palpable mass in the lower abdomen and a diffuse abdominal pain. Computed Tomography scan showed enlarged paraortic and mesenteric lymphadenopathy, thickness of the small bowel wall and dispersed masses intraperitoneally. He underwent an exploratory laparotomy and the resultant biopsy revealed desmoplastic small round cell tumor. Diagnosis of desmoplastic small round cell tumor can easily be missed because it presents with few early warning symptoms and signs, while the routine blood tests are within normal limits. A high degree of suspicion, a thorough physical examination, a full imaging check and an aggressive therapeutic approach are required in order to identify this disease and fight for a better quality of life for these patients. In addition we make a review of the literature in an effort to clarify the epidemiological, clinical and pathological aspects of this entity.

High School Physical Education Requirements and Youth Body Weight: New Evidence from the YRBS.

PubMed

Sabia, Joseph J; Nguyen, Thanh Tam; Rosenberg, Oren

2017-10-01

Previous research has found that high school physical education (PE) requirements are largely ineffective at reducing youth body weight. However, these studies were forced to rely on cross-state variation in PE requirements to identify their impacts, raising concerns that estimated policy effects may be confounded by state-level unobservables. Using data from the State and National Youth Risk Behavior Surveys and exploiting recent changes in state high school PE laws, we re-examine the effect of PE requirements on body weight. Our estimates show that a one-semester increase in PE requirements is associated with a 10 to 13% increase in minutes per week spent physically active in PE classes, but with no change in net vigorous exercise and little change in youth body weight. We conclude that substitution of in-school for outside-of-school physical activity and small resultant net energy expenditures can explain the absence of body weight effects. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Estimating the Return on Investment From a Health Risk Management Program Offered to Small Colorado-Based Employers

PubMed Central

Goetzel, Ron Z.; Tabrizi, Maryam; Henke, Rachel Mosher; Benevent, Richele; Brockbank, Claire v. S.; Stinson, Kaylan; Trotter, Margo; Newman, Lee S.

2015-01-01

Objective To determine whether changes in health risks for workers in small businesses can produce medical and productivity cost savings. Methods A 1-year pre- and posttest study tracked changes in 10 modifiable health risks for 2458 workers at 121 Colorado businesses that participated in a comprehensive worksite health promotion program. Risk reductions were entered into a return-on-investment (ROI) simulation model. Results Reductions were recorded in 10 risk factors examined, including obesity (−2.0%), poor eating habits (−5.8%), poor physical activity (−6.5%), tobacco use (−1.3%), high alcohol consumption (−1.7%), high stress (−3.5%), depression (−2.3%), high blood pressure (−0.3%), high total cholesterol (−0.9%), and high blood glucose (−0.2%). The ROI model estimated medical and productivity savings of $2.03 for every $1.00 invested. Conclusions Pooled data suggest that small businesses can realize a positive ROI from effective risk reduction programs. PMID:24806569

Increasing physical activity and exercise in lung cancer: reviewing safety, benefits, and application.

PubMed

Bade, Brett C; Thomas, D David; Scott, JoAnn B; Silvestri, Gerard A

2015-06-01

Lung cancer continues to be a difficult disease frequently diagnosed in late stages with a high mortality and symptom burden. In part because of frequent lung comorbidity, even lung cancer survivors often remain symptomatic and functionally limited. Though targeted therapy continues to increase treatment options for advanced-stage disease, symptom burden remains high with few therapeutic options. In the last several decades, exercise and physical activity have arisen as therapeutic options for obstructive lung disease and lung cancer. To date, exercise has been shown to reduce symptoms, increase exercise tolerance, improve quality of life, and potentially reduce length of stay and postoperative complications. Multiple small trials have been performed in perioperative non-small-cell lung cancer patients, although fewer studies are available for patients with advanced-stage disease. Despite the increased interest in this subject over the last few years, a validated exercise regimen has not been established for perioperative or advanced-stage disease. Clinicians underutilize exercise and pulmonary rehabilitation as a therapy, in part because of the lack of evidence-based consensus as to how and when to implement increasing physical activity. This review summarizes the existing evidence on exercise in lung cancer patients.

Sex differences in relative foot length and perceived attractiveness of female feet: relationships among anthropometry, physique, and preference ratings.

PubMed

Voracek, Martin; Fisher, Maryanne L; Rupp, Barbara; Lucas, Deanna; Fessler, Daniel M T

2007-06-01

Foot size proportionate to stature is smaller in women than in men, and small feet apparently contribute to perceived physical attractiveness of females. This exploratory study investigated the sex difference in relative foot length and interrelations among foot length, physique, and foot preference ratings in samples from Austria and Canada, each comprised of 75 men and 75 women. The findings included the following lines of evidence: the sex difference in relative foot length replicated in both data sets; the magnitude of this sex effect was large. Relative foot length was smaller in young, nulliparous, and slim women. Pointed-toe and high-heel shoes were more likely worn by smaller, lighter, and slimmer women. Men reported liking women's feet in general more than vice versa. A vast majority of both men and women favored small feet in women, but large feet in men. One's own foot size appeared to correspond to evaluations of attractiveness; particularly, women with small feet preferred small feet in women in general. The preference for small feet in women was convergent across different methods of evaluating attractiveness. Directions for investigations in this emerging field of research on physical attractiveness are discussed.

High resolution physical mapping of single gene fragments on pachytene chromosome 4 and 7 of Rosa.

PubMed

Kirov, Ilya V; Van Laere, Katrijn; Khrustaleva, Ludmila I

2015-07-02

Rosaceae is a family containing many economically important fruit and ornamental species. Although fluorescence in situ hybridization (FISH)-based physical mapping of plant genomes is a valuable tool for map-based cloning, comparative genomics and evolutionary studies, no studies using high resolution physical mapping have been performed in this family. Previously we proved that physical mapping of single-copy genes as small as 1.1 kb is possible on mitotic metaphase chromosomes of Rosa wichurana using Tyramide-FISH. In this study we aimed to further improve the physical map of Rosa wichurana by applying high resolution FISH to pachytene chromosomes. Using high resolution Tyramide-FISH and multicolor Tyramide-FISH, 7 genes (1.7-3 kb) were successfully mapped on pachytene chromosomes 4 and 7 of Rosa wichurana. Additionally, by using multicolor Tyramide-FISH three closely located genes were simultaneously visualized on chromosome 7. A detailed map of heterochromatine/euchromatine patterns of chromosome 4 and 7 was developed with indication of the physical position of these 7 genes. Comparison of the gene order between Rosa wichurana and Fragaria vesca revealed a poor collinearity for chromosome 7, but a perfect collinearity for chromosome 4. High resolution physical mapping of short probes on pachytene chromosomes of Rosa wichurana was successfully performed for the first time. Application of Tyramide-FISH on pachytene chromosomes allowed the mapping resolution to be increased up to 20 times compared to mitotic metaphase chromosomes. High resolution Tyramide-FISH and multicolor Tyramide-FISH might become useful tools for further physical mapping of single-copy genes and for the integration of physical and genetic maps of Rosa wichurana and other members of the Rosaceae.

250 Years of Physics at the College of William and Mary: 1760-2010

NASA Astrophysics Data System (ADS)

von Baeyer, Hans

2010-02-01

The recorded history of physics at William and Mary begins when Thomas Jefferson, the College's most distinguished alumnus, meets his mentor, Dr. William Small of Scotland, who opens his eyes to the wonders of natural philosophy. After the vicissitudes of the Revolution and the Civil War, physics enjoys a revival in the twentieth century, culminating in the creation of a Ph.D. program in the 1960s and the building of the William Small Physical Laboratory in Williamsburg. In the 1980s the modern era is launched by the establishment of the US Department of Energy's Jefferson Lab for nuclear physics in nearby Newport News. Today both Small Hall and Jefferson Lab are in the process of renovation. The legacies of Small and Jefferson for physics at William and Mary are secure! )

High school students' perceptions of physics

NASA Astrophysics Data System (ADS)

Checkley, Doug

There are far fewer high school students enrolled in physics than in chemistry or biology courses within the province of Alberta (Alberta Education, 2007). Students are also completing the highest level math course in larger numbers than those taking physics. It appears that a fear of physics exists within students in our province; this fear seems to be related to a level of difficulty the students associate with physics. Many students either opt to not take physics or enter the course with the expectation of failure. In this study I explored the impact of physics' reputation upon a group of students who chose not to take physics. In addition, I attempted to determine whether the perception of the difficulty of high school physics is accurate. This was done by investigating the perceptions of several students who took physics. I surveyed students from one high school in a small urban school district using group interviews. The students were in grades 10 to 12 and divided into groups of Science 10, Physics 20 and Physics 30 students. The students were interviewed to gain a deeper understanding of what perceptions they have about physics and why they may have them, hoping to identify factors that affect their academic decision to take or not take physics classes. For the students interviewed, I found that the biggest influence on their decisions to take or not take physics was related to their future aspirations. The students were also heavily influenced by their perceptions of physics. The students who took physics claimed that physics was not as difficult as they had believed it to be and they reported that it was interesting, enjoyable and relevant. Those students who had chosen to not take physics perceived it would be difficult, irrelevant and boring. Therefore, a major difference of perception exists between the students who took physics and those that did not.

Second teaching: An exploration of cognitive factors in small group physics learning

NASA Astrophysics Data System (ADS)

Novemsky, Lisa Forman

This inquiry was focused on an exploration of introductory physics teaching. Alan Van Heuvelen's Overview Case Study (OCS) physics was the pedagogical approach involving guided small group problem solving and stressing concepts first, before mathematics. Second teaching is a new pedagogical construct based on Vygotsky's ideas. Structured small group activity follows traditional instruction facilitating learning for non-traditional students. It is a model of structured small group activity designed to follow traditional instruction to facilitate the learning process for students who find a physics optic (way of seeing) and physics language foreign. In informal small group settins students describe, explain, elaborate, test, and defend ideas in their own familiar vernacular as they collaborate in solving problems. Collective wisdom of a collaborative group, somewhat beyond the level for each individual member, is created then recreated through self-correction. Students improved significantly in physics knowledge. In a classroom setting, small groups of non-traditional physics students engaged in second teaching were observed. Written explanations to conceptual physics questions were analyzed. Development of language usage in relationship to introductory physics concept learning was studied. Overall physics learning correlated positively with gains in language clarity thus confirming the hypothesis that language development can be linked with gains in physics knowledge. Males and females were found to be significantly different in this respect. Male gains in language clarity were closely coupled with physics learning whereas female gains in the two measures were not coupled. Physics discourse, particularly in relationship to force and motion, seems to resonate with natural developmentally acquired sex-typical male but not female discourse. Thus, for males but not for females, physics learning proceeds in a seamless fashion wherein knowledge gains are coupled with language development. Average frequency in use of the indeterminate pronoun it per person decreased. Reificiation of qualifying terms appeared in the form of a word-form problem. In the process of reifying adjectival properties students may be recapitulating the language-bound history of natural science.

The Gender Gap in High School Physics: Considering the Context of Local Communities

PubMed Central

2014-01-01

Objectives We focus on variation in gender inequality in physics course-taking, questioning the notion of a ubiquitous male advantage. We consider how inequality in high school physics is related to the context of students’ local communities, specifically the representation of women in STEM occupations in the labor force. Methods This study uses nationally representative data from the National Longitudinal Study of Adolescent Health (Add Health) and its education component, the Adolescent Health and Academic Achievement Transcript Study (AHAA). Results Approximately half of schools are characterized by either gender equality or even a small female advantage in enrollment in this traditionally male subject. Furthermore, variation in the gender gap in physics is related to the percent of women who are employed in STEM occupations within the community. Conclusion Our study suggests that communities differ in the extent to which traditionally gendered status expectations shape beliefs and behaviors. PMID:25605978

The peak velocity derived from the Carminatti Test is related to physical match performance in young soccer players.

PubMed

Fernandes-da-Silva, Juliano; Castagna, Carlo; Teixeira, Anderson Santiago; Carminatti, Lorival José; Guglielmo, Luiz Guilherme Antonacci

2016-12-01

The aim of this study was to examine the relationship between the peak velocity derived from the Carminatti Test (T-CAR) (PV T-CAR ) and physical match performance in young soccer players. Thirty-three youth soccer players were recruited from 2 non-professional clubs. Friendly matches and small-sided game were performed. Physical match demands were assessed using Global Positioning System (GPS) technology. On a separate occasion, the players were submitted to the T-CAR. Players were categorised into 3 groups based on their T-CAR performance: Low (PV T-CAR  ≤ P33), Intermediate (P33 > PV T-CAR  < P66) and High (PV T-CAR  ≥ P66). The PV T-CAR (15.5 ± 0.7 km·h -1 ) was significantly related to high-intensity activities (HIA; r = 0.78, P < 0.001), high-intensity running (HIR; r = 0.66, P < 0.001), sprinting (r = 0.62, P < 0.001) and total distance (TD) covered (r = 0.47, P < 0.01) during friendly matches. The PV T-CAR was strongly correlated with the amount of HIA (r = 0.81, P < 0.001), HIR (r = 0.85, P < 0.001) and TD covered (r = 0.81, P < 0.001) during small-sided game. No significant correlation was observed between the PV T-CAR and distance of sprinting (r = 0.49, P = 0.067) during small-side game. Furthermore, players in the High group covered significantly more TD (10%) and did more HIA (42%), sprinting (31%) and HIR (25%) during friendly matches compared to the players classified as having Low performance on the T-CAR. These differences still remained after adjusting for chronological age (CA), maturity and body size. In conclusion, the current study gives empirical support to the ecological and construct validity of this novel field test (T-CAR) as an indicator of match-related physical performance in young soccer players during pubertal years.

Studying three-phase supply in school

NASA Astrophysics Data System (ADS)

Singhal, Amit Kumar; Arun, P.

2009-07-01

The power distributions of nearly all major countries have accepted three-phase distribution as a standard. With increasing power requirements of instrumentation today even a small physics laboratory requires a three-phase supply. While physics students are given an introduction to this in passing, no experimental work is done with three-phase supply due to the possibility of accidents while working with such large power. We believe a conceptual understanding of three-phase supply would be useful for physics students, with hands-on experience using a simple circuit that can be assembled even in a high school laboratory.

UCTM2: An updated User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics

NASA Astrophysics Data System (ADS)

Bourrion, O.; Boyer, B.; Derome, L.; Pignol, G.

2016-06-01

We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

The effect of proximity on open-loop accommodation responses measured with pinholes.

PubMed

Morrison, K A; Seidel, D; Strang, N C; Gray, L S

2010-07-01

Open-loop accommodation levels were measured in 41 healthy, young subjects using a Shin-Nippon SRW-5000 autorefractor in the three viewing conditions: a small physical pinhole pupil (SP), an optically projected pinhole in Maxwellian view (MV) and in the dark (DF). The target viewed through the pinholes was a high-contrast letter presented at 0 D vergence in a +5 D Badal lens system. Overall, results showed that SP open-loop accommodation levels were significantly higher than MV and DF levels. Subjects could be divided into two distinct subgroups according to their response behaviour: responders to the proximal effect of the small physical pinhole (SP accommodation > MV accommodation) and non-responders to the proximal effect of the small physical pinhole (SP accommodation approximately MV accommodation). Correlation analysis demonstrated that open-loop accommodation for both pinhole conditions was correlated with DF for the responders, while for the non-responders SP and MV accommodation were correlated, but were not related to DF accommodation. This suggests that under open-loop conditions some individuals' accommodation levels are mainly affected by proximal and cognitive factors (responders) while others are guided primarily by the presence of the more distal target (non-responders). In conclusion, MV reduces the proximal effect of the physical pinhole and produces open-loop accommodation responses which are more consistent than SP and DF responses.

Search of the energetic gamma-ray experiment telescope (EGRET) data for high-energy gamma-ray microsecond bursts

NASA Technical Reports Server (NTRS)

Fichtel, C. E.; Bertsch, D. L.; Dingus, B. L.; Esposito, J. A.; Hartman, R. C.; Hunter, S. D.; Kanbach, G.; Kniffen, D. A.; Lin, Y. C.; Mattox, J. R.

1994-01-01

Hawking (1974) and Page & Hawking (1976) investigated theoretically the possibility of detecting high-energy gamma rays produced by the quantum-mechanical decay of a small black hole created in the early universe. They concluded that, at the very end of the life of the small black hole, it would radiate a burst of gamma rays peaked near 250 MeV with a total energy of about 10(exp 34) ergs in the order of a microsecond or less. The characteristics of a black hole are determined by laws of physics beyond the range of current particle accelerators; hence, the search for these short bursts of high-energy gamma rays provides at least the possibility of being the first test of this region of physics. The Compton Observatory Energetic Gamma-Ray Experiment Telescope (EGRET) has the capability of detecting directly the gamma rays from such bursts at a much fainter level than SAS 2, and a search of the EGRET data has led to an upper limit of 5 x 10(exp -2) black hole decays per cu pc per yr, placing constraints on this and other theories predicting microsecond high-energy gamma-ray bursts.

High Fidelity Modeling of Turbulent Mixing and Chemical Kinetics Interactions in a Post-Detonation Flow Field

NASA Astrophysics Data System (ADS)

Sinha, Neeraj; Zambon, Andrea; Ott, James; Demagistris, Michael

2015-06-01

Driven by the continuing rapid advances in high-performance computing, multi-dimensional high-fidelity modeling is an increasingly reliable predictive tool capable of providing valuable physical insight into complex post-detonation reacting flow fields. Utilizing a series of test cases featuring blast waves interacting with combustible dispersed clouds in a small-scale test setup under well-controlled conditions, the predictive capabilities of a state-of-the-art code are demonstrated and validated. Leveraging physics-based, first principle models and solving large system of equations on highly-resolved grids, the combined effects of finite-rate/multi-phase chemical processes (including thermal ignition), turbulent mixing and shock interactions are captured across the spectrum of relevant time-scales and length scales. Since many scales of motion are generated in a post-detonation environment, even if the initial ambient conditions are quiescent, turbulent mixing plays a major role in the fireball afterburning as well as in dispersion, mixing, ignition and burn-out of combustible clouds in its vicinity. Validating these capabilities at the small scale is critical to establish a reliable predictive tool applicable to more complex and large-scale geometries of practical interest.

Developing the Learning Physical Science Curriculum: Adapting a Small Enrollment, Laboratory and Discussion Based Physical Science Course for Large Enrollments

ERIC Educational Resources Information Center

Goldberg, Fred; Price, Edward; Robinson, Stephen; Boyd-Harlow, Danielle; McKean, Michael

2012-01-01

We report on the adaptation of the small enrollment, lab and discussion based physical science course, "Physical Science and Everyday Thinking" (PSET), for a large-enrollment, lecture-style setting. Like PSET, the new "Learning Physical Science" (LEPS) curriculum was designed around specific principles based on research on learning to meet the…

A meta-meta-analysis of the effect of physical activity on depression and anxiety in non-clinical adult populations.

PubMed

Rebar, Amanda L; Stanton, Robert; Geard, David; Short, Camille; Duncan, Mitch J; Vandelanotte, Corneel

2015-01-01

Amidst strong efforts to promote the therapeutic benefits of physical activity for reducing depression and anxiety in clinical populations, little focus has been directed towards the mental health benefits of activity for non-clinical populations. The objective of this meta-meta-analysis was to systematically aggregate and quantify high-quality meta-analytic findings of the effects of physical activity on depression and anxiety for non-clinical populations. A systematic search identified eight meta-analytic outcomes of randomised trials that investigated the effects of physical activity on depression or anxiety. The subsequent meta-meta-analyses were based on a total of 92 studies with 4310 participants for the effect of physical activity on depression and 306 study effects with 10,755 participants for the effect of physical activity on anxiety. Physical activity reduced depression by a medium effect [standardised mean difference (SMD) = -0.50; 95% CI: -0.93 to -0.06] and anxiety by a small effect (SMD = -0.38; 95% CI: -0.66 to -0.11). Neither effect showed significant heterogeneity across meta-analyses. These findings represent a comprehensive body of high-quality evidence that physical activity reduces depression and anxiety in non-clinical populations.

Tumour and normal tissue radiobiology in mouse models: how close are mice to mini-humans?

PubMed

Koontz, Bridget F; Verhaegen, Frank; De Ruysscher, Dirk

2017-01-01

Animal modelling is essential to the study of radiobiology and the advancement of clinical radiation oncology by providing preclinical data. Mouse models in particular have been highly utilized in the study of both tumour and normal tissue radiobiology because of their cost effectiveness and versatility. Technology has significantly advanced in preclinical radiation techniques to allow highly conformal image-guided irradiation of small animals in an effort to mimic human treatment capabilities. However, the biological and physical limitations of animal modelling should be recognized and considered when interpreting preclinical radiotherapy (RT) studies. Murine tumour and normal tissue radioresponse has been shown to vary from human cellular and molecular pathways. Small animal irradiation techniques utilize different anatomical boundaries and may have different physical properties than human RT. This review addresses the difference between the human condition and mouse models and discusses possible strategies for future refinement of murine models of cancer and radiation for the benefit of both basic radiobiology and clinical translation.

Tumour and normal tissue radiobiology in mouse models: how close are mice to mini-humans?

PubMed Central

Verhaegen, Frank; De Ruysscher, Dirk

2017-01-01

Animal modelling is essential to the study of radiobiology and the advancement of clinical radiation oncology by providing preclinical data. Mouse models in particular have been highly utilized in the study of both tumour and normal tissue radiobiology because of their cost effectiveness and versatility. Technology has significantly advanced in preclinical radiation techniques to allow highly conformal image-guided irradiation of small animals in an effort to mimic human treatment capabilities. However, the biological and physical limitations of animal modelling should be recognized and considered when interpreting preclinical radiotherapy (RT) studies. Murine tumour and normal tissue radioresponse has been shown to vary from human cellular and molecular pathways. Small animal irradiation techniques utilize different anatomical boundaries and may have different physical properties than human RT. This review addresses the difference between the human condition and mouse models and discusses possible strategies for future refinement of murine models of cancer and radiation for the benefit of both basic radiobiology and clinical translation. PMID:27612010

Job strain in physical therapists.

PubMed

Campo, Marc A; Weiser, Sherri; Koenig, Karen L

2009-09-01

Job stress has been associated with poor outcomes. In focus groups and small-sample surveys, physical therapists have reported high levels of job stress. Studies of job stress in physical therapy with larger samples are needed. The purposes of this study were: (1) to determine the levels of psychological job demands and job control reported by physical therapists in a national sample, (2) to compare those levels with national norms, and (3) to determine whether high demands, low control, or a combination of both (job strain) increases the risk for turnover or work-related pain. This was a prospective cohort study with a 1-year follow-up period. Participants were randomly selected members of the American Physical Therapy Association (n=882). Exposure assessments included the Job Content Questionnaire (JCQ), a commonly used instrument for evaluation of the psychosocial work environment. Outcomes included job turnover and work-related musculoskeletal disorders. Compared with national averages, the physical therapists reported moderate job demands and high levels of job control. About 16% of the therapists reported changing jobs during follow-up. Risk factors for turnover included high job demands, low job control, job strain, female sex, and younger age. More than one half of the therapists reported work-related pain. Risk factors for work-related pain included low job control and job strain. The JCQ measures only limited dimensions of the psychosocial work environment. All data were self-reported and subject to associated bias. Physical therapists' views of their work environments were positive, including moderate levels of demands and high levels of control. Those therapists with high levels of demands and low levels of control, however, were at increased risk for both turnover and work-related pain. Physical therapists should consider the psychosocial work environment, along with other factors, when choosing a job.

Losing and Saving and Losing Physics in Texas

NASA Astrophysics Data System (ADS)

Marder, Michael

2015-03-01

Texas has the second-largest population of the states, and played even a larger role in education reform movements of the past 15 years than its size would indicate. In the Fall of 2011, physicists across the country were surprised to learn that six university physics programs in Texas were threatened with closure because of small graduation numbers. Five of them ultimately closed. Many of the faculty at the institutions losing programs came together and formed a consortium that eventually made it possible to continue offering physics,by unconventional means, to their undergraduates. In the Spring of 2013 came an even larger change. Physics had been part of the recommended high school graduation plan in Texas. As part of a bill making sweeping changes to high school graduation requirements and accountability, the physics requirement was removed. Physics may partly be falling victim to the national focus on STEM, which suggests that the various disciplines of science are interchangeable and not individually important. None of the changes in Texas are hard to imagine coming to other states as well.

Physics and Entrepreneurship: A Small Business Perspective

NASA Astrophysics Data System (ADS)

Cleveland, Jason

2013-03-01

DARPA's Microsystems Technology Office, MTO, conceives and develops a wide range of technologies to benefit the US warfighter, from exotic GaN transistors to high-power fiber lasers, highly efficient embedded computer systems to synthetic biology. MTO has world class electrical and mechanical engineers, but we also have a cadre of extremely capable physicists, whose complementary skillset has been absolutely essential to identifying promising technological avenues for the office and for the agency. In this talk I will explain the DARPA model of technology development, using real examples from MTO, highlighting programs where physics-based insights have led to important new capabilities for the Dept of Defense.

The NCGC Pharmaceutical Collection: A comprehensive resource of clinically approved drugs enabling repurposing and chemical genomics

PubMed Central

Huang, Ruili; Southall, Noel; Wang, Yuhong; Yasgar, Adam; Shinn, Paul; Jadhav, Ajit; Nguyen, Dac-Trung; Austin, Christopher P.

2011-01-01

Small-molecule compounds approved for use as drugs may be “repurposed” for new indications and studied to determine the mechanisms of their beneficial and adverse effects. A comprehensive collection of all small-molecule drugs approved for human use would be invaluable for systematic repurposing across human diseases, particularly for rare and neglected diseases, for which the cost and time required for development of a new chemical entity are often prohibitive. Previous efforts to build such a comprehensive collection have been limited by the complexities, redundancies, and semantic inconsistencies of drug naming within and among regulatory agencies worldwide; a lack of clear conceptualization of what constitutes a drug; and a lack of access to physical samples. We report here the creation of a definitive, complete, and nonredundant list of all approved molecular entities as a freely available electronic resource and a physical collection of small molecules amenable to high-throughput screening. PMID:21525397

Forgotten Trailblazers: The History of Women in Physics and Astronomy

NASA Astrophysics Data System (ADS)

Muir, Fiona

2014-03-01

While female physicists and astronomers have historically made up a relatively small fraction of the community as a whole, this was not the only thing holding back women in physics. Even the most prominent women have had their achievements overlooked and diminished. As part of a Society of Physics Students internship at the American Institute of Physics' Center for History of Physics, we researched the lives and work of a range of women in physics, covering a wide span of geographical areas and eras in history. This information was compiled in to lesson plans for high school and college age students, focusing on specific women or certain overarching themes such as collaborative married couples. In this talk, I will discuss our research methods and include examples of the lesson plans and their applications. Completed as part of the SPS internship programme.

Ecological literacy through critical/place-based pedagogy in the environmental studies program at a small liberal arts college

NASA Astrophysics Data System (ADS)

Beeman-Cadwallader, Nicole

In 2007 Pioneer High School, a public school in Whittier, California changed the sequence of its science courses from the Traditional Biology-Chemistry-Physics (B-C-P) to Biology-Physics-Chemistry (B-P-C), or "Physics Second." The California Standards Tests (CSTs) scores in Physics and Chemistry from 2004-2012 were used to determine if there were any effects of the Physics Second sequencing on student achievement in those courses. The data was also used to determine whether the Physics Second sequence had an effect on performance in Physics and Chemistry based on gender. Independent t tests and chi-square analysis of the data determined an improvement in student performance in Chemistry but not Physics. The 2x2 Factorial ANOVA analysis revealed that in Physics male students performed better on the CSTs than their female peers. In Chemistry, it was noted that male and female students performed equally well. Neither finding was a result ofthe change to the "Physics Second" sequencing.

Process Defects in Composites.

DTIC Science & Technology

1995-01-30

mean velocity, U, a high kinematic viscosity, v , and a small diameter of the fibers, D , lead to a very small Reynolds number Re = UD << 1 (1) where p is...partial credit to ARO). 9. D . Krajcinovic and S . Mastilovic, "Damage Evolution and Failure Modes", in: Proc. of the Int. Conf. on Computational...34Computer Simulation of a Model for Irreversible Gelation", Journal of Physics A, Vol. 16., pp. 1221-1239. Kuksenko, V . S . and Tamuzs, V . P., 1981

Leisure-time physical activity and sciatica: A systematic review and meta-analysis

PubMed Central

Shiri, R.; Falah-Hassani, K.; Viikari-Juntura, E.; Coggon, D.

2016-01-01

Background and objective The role of leisure-time physical activity in sciatica is uncertain. This study aimed to assess the association of leisure-time physical activity with lumbar radicular pain and sciatica. Databases and data treatment Literature searches were conducted in PubMed, Embase, Web of Science, Scopus, Google Scholar and ResearchGate databases from 1964 through August 2015. A random-effects meta-analysis was performed, and heterogeneity and small-study bias were assessed. Results Ten cohort (N=82,024 participants), 4 case-control (N=9350) and 4 cross-sectional (N=10,046)) studies qualified for meta-analysis. In comparison with no regular physical activity, high level of physical activity (≥4 times/week) was inversely associated with new onset of lumbar radicular pain or sciatica in a meta-analysis of prospective cohort studies (risk ratio (RR)=0.88, 95% CI 0.78-0.99, I2=0%, 7 studies, N=78,065). The association for moderate level of physical activity (1-3 times/week) was weaker (RR=0.93, CI 0.82-1.05, I2=0%, 6 studies, N=69,049), and there was no association with physical activity for at least once/week (RR=0.99, CI 0.86-1.13, 9 studies, N=73,008). On the contrary, a meta-analysis of cross-sectional studies showed a higher prevalence of lumbar radicular pain or sciatica in participants who exercised at least once/week (prevalence ratio (PR)=1.29, CI 1.09-1.53, I2=0%, 4 studies, N=10,046), or 1-3 times/week (PR=1.34, CI 1.02-1.77, I2=0%, N=7631) than among inactive participants. There was no evidence of small-study bias. Conclusions This meta-analysis suggests that moderate to high level of leisure physical activity may have a moderate protective effect against development of lumbar radicular pain. However, a large reduction in risk (>30%) seems unlikely. PMID:27091423

Power Play, Laser Style

NASA Technical Reports Server (NTRS)

1998-01-01

Under a NASA SBIR (Small Business Innovation Research) SDL, Inc., has developed the TC40 Single-Frequency Continuously Tunable 500 mw Laser Diode System. This is the first commercially available single frequency diode laser system that offers the broad tunability and the high powers needed for atomic cooling and trapping as well as a variety of atomic spectroscopy techniques. By greatly decreasing both the equipment and the costs of entry, the TC40 enables researchers to pursue some of the most interesting areas of physical chemistry, biochemistry, and atomic physics.

--No Title--

Science.gov Websites

time. It is usually measured in radians per second. Anisotropy- Physical property values that vary when negative charge. When an antimatter particle collides with its normal-matter counterpart, both particles neutrons. Big Bang- The violent cosmic explosion of an incredibly small amount of matter at high

How Do Chinese College Students Define Sexual Harassment?

ERIC Educational Resources Information Center

Tang, Catherine So-Kum; And Others

1995-01-01

Indicates Chinese students have a high level of consensus in regarding overt unwelcome physical contact and coercive sexuality as sexual harassment. A small percentage of respondents classified sexist and misogynistic behaviors, pressure for dates, and unsolicited disclosure of personal and emotional feelings as sexually harassing. Women had…

Exploring Low Internal Reorganization Energies for Silicene Nanoclusters

NASA Astrophysics Data System (ADS)

Pablo-Pedro, Ricardo; Lopez-Rios, Hector; Mendoza-Cortes, Jose-L.; Kong, Jing; Fomine, Serguei; Van Voorhis, Troy; Dresselhaus, Mildred S.

2018-05-01

This paper is a contribution to the Physical Review Applied collection in memory of Mildred S. Dresselhaus. High-performance materials rely on small reorganization energies to facilitate both charge separation and charge transport. Here, we perform density-functional-theory calculations to predict small reorganization energies of rectangular silicene nanoclusters with hydrogen-passivated edges denoted by H-SiNC. We observe that across all geometries, H-SiNCs feature large electron affinities and highly stabilized anionic states, indicating their potential as n -type materials. Our findings suggest that fine-tuning the size of H-SiNCs along the "zigzag" and "armchair" directions may permit the design of novel n -type electronic materials and spintronics devices that incorporate both high electron affinities and very low internal reorganization energies.

Psychosocial correlates to high school girls' leisure-time physical activity: a test of the theory of planned behavior.

PubMed

Kerner, Matthew S; Kurrant, Anthony B

2003-12-01

This study was designed to test the efficacy of the theory of planned behavior in predicting intention to engage in leisure-time physical activity and leisure-time physical activity behavior of high school girls. Rating scales were used for assessing attitude to leisure-time physical activity, subjective norm, perceived control, and intention to engage in leisure-time physical activity among 129 ninth through twelfth graders. Leisure-time physical activity was obtained from 3-wk. diaries. The first hierarchical multiple regression indicated that perceived control added (R2 change = .033) to the contributions of attitude to leisure-time physical activity and subjective norm in accounting for 50.7% of the total variance of intention to engage in leisure-time physical activity. The second regression analysis indicated that almost 10% of the variance of leisure-time physical activity was explicated by intention to engage in leisure-time physical activity and perceived control, with perceived control contributing 6.4%. From both academic and theoretical standpoints, our findings support the theory of planned behavior, although quantitatively the variance of leisure-time physical activity was not well-accounted for. In addition, considering the small percentage increase in variance explained by the addition of perceived control explaining variance of intention to engage in leisure-time physical activity, the pragmatism of implementing the measure of perceived control is questionable for this population.

Quantum Talk: How Small-Group Discussions May Enhance Students' Understanding in Quantum Physics

ERIC Educational Resources Information Center

Bungum, Berit; Bøe, Maria Vetleseter; Henriksen, Ellen Karoline

2018-01-01

Quantum physics challenges our views of the physical world and describes phenomena that cannot be directly observed. The use of language is hence essential in the teaching of quantum physics. With a sociocultural view of learning, we investigate characteristics of preuniversity students' small-group discussions and their potential for enhancing…

Preparing Historically Underserved Students for STEM Careers: The Role of an Inquiry-based High School Science Sequence Beginning with Physics

NASA Astrophysics Data System (ADS)

Bridges, Jon P.

Improving the STEM readiness of students from historically underserved groups is a moral and economic imperative requiring greater attention and effort than has been shown to date. The current literature suggests a high school science sequence beginning with physics and centered on developing conceptual understanding, using inquiry labs and modeling to allow students to explore new ideas, and addressing and correcting student misconceptions can increase student interest in and preparation for STEM careers. The purpose of this study was to determine if the science college readiness of historically underserved students can be improved by implementing an inquiry-based high school science sequence comprised of coursework in physics, chemistry, and biology for every student. The study used a retrospective cohort observational design to address the primary research question: are there differences between historically underserved students completing a Physics First science sequence and their peers completing a traditional science sequence in 1) science college-readiness test scores, 2) rates of science college-and career-readiness, and 3) interest in STEM? Small positive effects were found for all three outcomes for historically underserved students in the Physics First sequence.

Research on fast algorithm of small UAV navigation in non-linear matrix reductionism method

NASA Astrophysics Data System (ADS)

Zhang, Xiao; Fang, Jiancheng; Sheng, Wei; Cao, Juanjuan

2008-10-01

The low Reynolds numbers of small UAV will result in unfavorable aerodynamic conditions to support controlled flight. And as operated near ground, the small UAV will be affected seriously by low-frequency interference caused by atmospheric disturbance. Therefore, the GNC system needs high frequency of attitude estimation and control to realize the steady of the UAV. In company with the dimensional of small UAV dwindling away, its GNC system is more and more taken embedded designing technology to reach the purpose of compactness, light weight and low power consumption. At the same time, the operational capability of GNC system also gets limit in a certain extent. Therefore, a kind of high speed navigation algorithm design becomes the imminence demand of GNC system. Aiming at such requirement, a kind of non-linearity matrix reduction approach is adopted in this paper to create a new high speed navigation algorithm which holds the radius of meridian circle and prime vertical circle as constant and linearizes the position matrix calculation formulae of navigation equation. Compared with normal navigation algorithm, this high speed navigation algorithm decreases 17.3% operand. Within small UAV"s mission radius (20km), the accuracy of position error is less than 0.13m. The results of semi-physical experiments and small UAV's auto pilot testing proved that this algorithm can realize high frequency attitude estimation and control. It will avoid low-frequency interference caused by atmospheric disturbance properly.

The effect and importance of physical activity on behavioural and psychological symptoms in people with dementia: A systematic mixed studies review.

PubMed

Junge, Tina; Ahler, Jonas; Knudsen, Hans K; Kristensen, Hanne K

2018-01-01

Background People with dementia may benefit from the effect of physical activity on behavioural and psychological symptoms of dementia. Qualitative synthesis of the importance of physical activity might complement and help clarify quantitative findings on this topic. The purpose of this systematic mixed studies review was to evaluate findings from both quantitative and qualitative methods about the effect and importance of physical activity on behavioural and psychological symptoms of dementia in people with dementia. Methods The systematic literature search was conducted in EMBASE, CINAHL, PubMed, PEDro and PsycINFO. Inclusion criteria were: people with a light to moderate degree of dementia, interventions including physical activity and outcomes focusing on behavioural and psychological symptoms of dementia or quality of life. To assess the methodological quality of the studies, the AMSTAR and GRADE checklists were applied for the quantitative studies and the CASP qualitative checklist for the qualitative studies. Results A small reduction in depression level and improved mood were seen in some quantitative studies of multi-component physical activity interventions, including walking. Due to high heterogeneity in the quantitative studies, a single summary of the effect of physical activity on behavioural and psychological symptoms of dementia should be interpreted with some caution. Across the qualitative studies, the common themes about the importance of physical activity were its 'socially rewarding' nature, the 'benefits of walking outdoors' and its contribution to 'maintaining self-hood'. Conclusion For people with dementia, there was a small, quantitative effect of multi-component physical activity including walking, on depression level and mood. People with dementia reported the importance of walking outdoors, experiencing the social rewards of physical activity in groups, as well as physical activity were a means toward maintaining self-hood.

Physical data measurements and mathematical modelling of simple gas bubble experiments in glass melts

NASA Technical Reports Server (NTRS)

Weinberg, Michael C.

1986-01-01

In this work consideration is given to the problem of the extraction of physical data information from gas bubble dissolution and growth measurements. The discussion is limited to the analysis of the simplest experimental systems consisting of a single, one component gas bubble in a glassmelt. It is observed that if the glassmelt is highly under- (super-) saturated, then surface tension effects may be ignored, simplifying the task of extracting gas diffusivity values from the measurements. If, in addition, the bubble rise velocity is very small (or very large) the ease of obtaining physical property data is enhanced. Illustrations are given for typical cases.

Pelletizing properties of torrefied spruce

Treesearch

Wolfgang Stelte; Craig Clemons; Jens K. Holm; Anand R. Sanadi; Jesper Ahrenfeldt; Lei Shang; Ulrik B. Henriksen

2011-01-01

Torrefaction is a thermo-chemical conversion process improving the handling, storage and combustion properties of wood. To save storage space and transportation costs, it can be compressed into fuel pellets of high physical and energetic density. The resulting pellets are relatively resistant to moisture uptake, microbiological decay and easy to comminute into small...

Small size transformer provides high power regulation with low ripple and maximum control

NASA Technical Reports Server (NTRS)

Manoli, R.; Ulrich, B. R.

1971-01-01

Single, variable, transformer/choke device does work of several. Technique reduces drawer assembly physical size and design and manufacturing cost. Device provides power, voltage current and impedance regulation while maintaining maximum control of linearity and ensuring extremely low ripple. Nulling is controlled to very fine degree.

High Resolution Observations and Modeling of Small-Scale Solar Magnetic Elements

NASA Technical Reports Server (NTRS)

Berger, Thomas E.

2001-01-01

This research contract investigating the radiative transfer and dynamic physics of the smallest observable magnetic structures in the solar photosphere. Due to the lack of a high-resolution visible light satellite instrument for solar studies, all data were acquired using ground-based instrumentation. The primary goal of the investigation was to understand the formation and evolution of "G-band bright points" in relation to the associated magnetic elements. G-band bright points are small (on the order of 100 kin or less in diameter) bright signatures associated with magnetic flux elements in the photosphere. They are seen in the A2A-X2 4308 A molecular bandhead of the CH radical ill the solar spectrum and offer the highest spatial resolution and highest contrast "tracers" of small magnetic structure on the Sun.

a Study of Ultrasonic Wave Propagation Through Parallel Arrays of Immersed Tubes

NASA Astrophysics Data System (ADS)

Cocker, R. P.; Challis, R. E.

1996-06-01

Tubular array structures are a very common component in industrial heat exchanging plant and the non-destructive testing of these arrays is essential. Acoustic methods using microphones or ultrasound are attractive but require a thorough understanding of the acoustic properties of tube arrays. This paper details the development and testing of a small-scale physical model of a tube array to verify the predictions of a theoretical model for acoustic propagation through tube arrays developed by Heckl, Mulholland, and Huang [1-5] as a basis for the consideration of small-scale physical models in the development of non-destructive testing procedures for tube arrays. Their model predicts transmission spectra for plane waves incident on an array of tubes arranged in straight rows. Relative transmission is frequency dependent with bands of high and low attenuation caused by resonances within individual tubes and between tubes in the array. As the number of rows in the array increases the relative transmission spectrum becomes more complex, with increasingly well-defined bands of high and low attenuation. Diffraction of acoustic waves with wavelengths less than the tube spacing is predicted and appears as step reductions in the transmission spectrum at frequencies corresponding to integer multiples of the tube spacing. Experiments with the physical model confirm the principle features of the theoretical treatment.

Involving High School Students in Computational Physics University Research: Theory Calculations of Toluene Adsorbed on Graphene

PubMed Central

Borck, Øyvind; Gunnarsson, Linda; Lydmark, Pär

2016-01-01

To increase public awareness of theoretical materials physics, a small group of high school students is invited to participate actively in a current research projects at Chalmers University of Technology. The Chalmers research group explores methods for filtrating hazardous and otherwise unwanted molecules from drinking water, for example by adsorption in active carbon filters. In this project, the students use graphene as an idealized model for active carbon, and estimate the energy of adsorption of the methylbenzene toluene on graphene with the help of the atomic-scale calculational method density functional theory. In this process the students develop an insight into applied quantum physics, a topic usually not taught at this educational level, and gain some experience with a couple of state-of-the-art calculational tools in materials research. PMID:27505418

Involving High School Students in Computational Physics University Research: Theory Calculations of Toluene Adsorbed on Graphene.

PubMed

Ericsson, Jonas; Husmark, Teodor; Mathiesen, Christoffer; Sepahvand, Benjamin; Borck, Øyvind; Gunnarsson, Linda; Lydmark, Pär; Schröder, Elsebeth

2016-01-01

To increase public awareness of theoretical materials physics, a small group of high school students is invited to participate actively in a current research projects at Chalmers University of Technology. The Chalmers research group explores methods for filtrating hazardous and otherwise unwanted molecules from drinking water, for example by adsorption in active carbon filters. In this project, the students use graphene as an idealized model for active carbon, and estimate the energy of adsorption of the methylbenzene toluene on graphene with the help of the atomic-scale calculational method density functional theory. In this process the students develop an insight into applied quantum physics, a topic usually not taught at this educational level, and gain some experience with a couple of state-of-the-art calculational tools in materials research.

Development and Application of Stable Phantoms for the Evaluation of Photoacoustic Imaging Instruments

PubMed Central

Bohndiek, Sarah E.; Bodapati, Sandhya; Van De Sompel, Dominique; Kothapalli, Sri-Rajasekhar; Gambhir, Sanjiv S.

2013-01-01

Photoacoustic imaging combines the high contrast of optical imaging with the spatial resolution and penetration depth of ultrasound. This technique holds tremendous potential for imaging in small animals and importantly, is clinically translatable. At present, there is no accepted standard physical phantom that can be used to provide routine quality control and performance evaluation of photoacoustic imaging instruments. With the growing popularity of the technique and the advent of several commercial small animal imaging systems, it is important to develop a strategy for assessment of such instruments. Here, we developed a protocol for fabrication of physical phantoms for photoacoustic imaging from polyvinyl chloride plastisol (PVCP). Using this material, we designed and constructed a range of phantoms by tuning the optical properties of the background matrix and embedding spherical absorbing targets of the same material at different depths. We created specific designs to enable: routine quality control; the testing of robustness of photoacoustic signals as a function of background; and the evaluation of the maximum imaging depth available. Furthermore, we demonstrated that we could, for the first time, evaluate two small animal photoacoustic imaging systems with distinctly different light delivery, ultrasound imaging geometries and center frequencies, using stable physical phantoms and directly compare the results from both systems. PMID:24086557

‘Small Changes’ to Diet and Physical Activity Behaviors for Weight Management

PubMed Central

Hills, Andrew P.; Byrne, Nuala M.; Lindstrom, Rachel; Hill, James O.

2013-01-01

Obesity is associated with numerous short- and long-term health consequences. Low levels of physical activity and poor dietary habits are consistent with an increased risk of obesity in an obesogenic environment. Relatively little research has investigated associations between eating and activity behaviors by using a systems biology approach and by considering the dynamics of the energy balance concept. A significant body of research indicates that a small positive energy balance over time is sufficient to cause weight gain in many individuals. In contrast, small changes in nutrition and physical activity behaviors can prevent weight gain. In the context of weight management, it may be more feasible for most people to make small compared to large short-term changes in diet and activity. This paper presents a case for the use of small and incremental changes in diet and physical activity for improved weight management in the context of a toxic obesogenic environment. PMID:23711772

Can exergaming contribute to improving physical activity levels and health outcomes in children?

PubMed

Daley, Amanda J

2009-08-01

Physical inactivity among children is a serious public health problem. It has been suggested that high levels of screen time are contributory factors that encourage sedentary lifestyles in young people. As physical inactivity and obesity levels continue to rise in young people, it has been proposed that new-generation active computer- and video-console games (otherwise known as "exergaming") may offer the opportunity to contribute to young people's energy expenditure during their free time. Although studies have produced some encouraging results regarding the energy costs involved in playing active video-console games, the energy costs of playing the authentic versions of activity-based video games are substantially larger, highlighting that active gaming is no substitute for real sports and activities. A small number of exergaming activities engage children in moderate-intensity activity, but most do not. Only 3 very small trials have considered the effects of exergaming on physical activity levels and/or other health outcomes in children. Evidence from these trials has been mixed; positive trends for improvements in some health outcomes in the intervention groups were noted in 2 trials. No adequately powered randomized, controlled trial has been published to date, and no trial has assessed the long-term impact of exergaming on children's health. We now need high-quality randomized, controlled trials to evaluate the effectiveness and sustainability of exergaming, as well as its clinical relevance; until such studies take place, we should remain cautious about its ability to positively affect children's health.

Physical and psychosocial benefits of yoga in cancer patients and survivors, a systematic review and meta-analysis of randomized controlled trials

PubMed Central

2012-01-01

Background This study aimed to systematically review the evidence from randomized controlled trials (RCTs) and to conduct a meta-analysis of the effects of yoga on physical and psychosocial outcomes in cancer patients and survivors. Methods A systematic literature search in ten databases was conducted in November 2011. Studies were included if they had an RCT design, focused on cancer patients or survivors, included physical postures in the yoga program, compared yoga with a non-exercise or waitlist control group, and evaluated physical and/or psychosocial outcomes. Two researchers independently rated the quality of the included RCTs, and high quality was defined as >50% of the total possible score. Effect sizes (Cohen’s d) were calculated for outcomes studied in more than three studies among patients with breast cancer using means and standard deviations of post-test scores of the intervention and control groups. Results Sixteen publications of 13 RCTs met the inclusion criteria, of which one included patients with lymphomas and the others focused on patients with breast cancer. The median quality score was 67% (range: 22–89%). The included studies evaluated 23 physical and 20 psychosocial outcomes. Of the outcomes studied in more than three studies among patients with breast cancer, we found large reductions in distress, anxiety, and depression (d = −0.69 to −0.75), moderate reductions in fatigue (d = −0.51), moderate increases in general quality of life, emotional function and social function (d = 0.33 to 0.49), and a small increase in functional well-being (d = 0.31). Effects on physical function and sleep were small and not significant. Conclusion Yoga appeared to be a feasible intervention and beneficial effects on several physical and psychosocial symptoms were reported. In patients with breast cancer, effect size on functional well-being was small, and they were moderate to large for psychosocial outcomes. PMID:23181734

Small Schools Curriculum: Physical Education, K-6.

ERIC Educational Resources Information Center

Hartl, David, Ed.; Hartl, Doris, Ed.

The self-contained sections within the document (one for grades K-3, the other for grades 4-6) present objectives, activities, monitoring procedures and resources for the elementary physical education curriculum for Washington small school districts. Identical introductory materials describe the organization of Small Schools materials,…

Hidden physics models: Machine learning of nonlinear partial differential equations

NASA Astrophysics Data System (ADS)

Raissi, Maziar; Karniadakis, George Em

2018-03-01

While there is currently a lot of enthusiasm about "big data", useful data is usually "small" and expensive to acquire. In this paper, we present a new paradigm of learning partial differential equations from small data. In particular, we introduce hidden physics models, which are essentially data-efficient learning machines capable of leveraging the underlying laws of physics, expressed by time dependent and nonlinear partial differential equations, to extract patterns from high-dimensional data generated from experiments. The proposed methodology may be applied to the problem of learning, system identification, or data-driven discovery of partial differential equations. Our framework relies on Gaussian processes, a powerful tool for probabilistic inference over functions, that enables us to strike a balance between model complexity and data fitting. The effectiveness of the proposed approach is demonstrated through a variety of canonical problems, spanning a number of scientific domains, including the Navier-Stokes, Schrödinger, Kuramoto-Sivashinsky, and time dependent linear fractional equations. The methodology provides a promising new direction for harnessing the long-standing developments of classical methods in applied mathematics and mathematical physics to design learning machines with the ability to operate in complex domains without requiring large quantities of data.

Small-x Physics: From HERA to LHC and beyond

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leonid Frankfurt; Mark Strikman; Christian Weiss

2005-07-01

We summarize the lessons learned from studies of hard scattering processes in high-energy electron-proton collisions at HERA and antiproton-proton collisions at the Tevatron, with the aim of predicting new strong interaction phenomena observable in next-generation experiments at the Large Hadron Collider (LHC). Processes reviewed include inclusive deep-inelastic scattering (DIS) at small x exclusive and diffractive processes in DIS and hadron-hadron scattering, as well as color transparency and nuclear shadowing effects. A unified treatment of these processes is outlined, based on factorization theorems of quantum chromodynamics, and using the correspondence between the ''parton'' picture in the infinite-momentum frame and the 'dipole''more » picture of high-energy processes in the target rest frame. The crucial role of the three-dimensional quark and gluon structure of the nucleon is emphasized. A new dynamical effect predicted at high energies is the unitarity, or black disk, limit (BDL) in the interaction of small dipoles with hadronic matter, due to the increase of the gluon density at small x. This effect is marginally visible in diffractive DIS at HERA and will lead to the complete disappearance of Bjorken scaling at higher energies. In hadron-hadron scattering at LHC energies and beyond (cosmic ray physics), the BDL will be a standard feature of the dynamics, with implications for (a) hadron production at forward and central rapidities in central proton-proton and proton-nucleus collisions, in particular events with heavy particle production (Higgs), (b) proton-proton elastic scattering, (c) heavy-ion collisions. We also outline the possibilities for studies of diffractive processes and photon-induced reactions (ultraperipheral collisions) at LHC, as well as possible measurements with a future electron-ion collider.« less

Using a 400 kV Van de Graaff accelerator to teach physics at West Point

NASA Astrophysics Data System (ADS)

Marble, D. K.; Bruch, S. E.; Lainis, T.

1997-02-01

A small accelerator visitation laboratory is being built at the United States Military Academy using two 400 kV Van de Graaff accelerators. This laboratory will provide quality teaching experiments and increased research opportunities for both faculty and cadets as well as enhancing the department's ability to teach across the curriculum by using nuclear techniques to solve problems in environmental engineering, material science, archeology, art, etc. This training enhances a students ability to enter non-traditional fields that are becoming a large part of the physics job market. Furthermore, a small accelerator visitation laboratory for high school students can stimulate student interest in science and provide an effective means of communicating the scientific method to a general audience. A discussion of the USMA facility, class experiments and student research projects will be presented.

Quantification of unsteady heat transfer and phase changing process inside small icing water droplets.

PubMed

Jin, Zheyan; Hu, Hui

2009-05-01

We report progress made in our recent effort to develop and implement a novel, lifetime-based molecular tagging thermometry (MTT) technique to quantify unsteady heat transfer and phase changing process inside small icing water droplets pertinent to wind turbine icing phenomena. The lifetime-based MTT technique was used to achieve temporally and spatially resolved temperature distribution measurements within small, convectively cooled water droplets to quantify unsteady heat transfer within the small water droplets in the course of convective cooling process. The transient behavior of phase changing process within small icing water droplets was also revealed clearly by using the MTT technique. Such measurements are highly desirable to elucidate underlying physics to improve our understanding about important microphysical phenomena pertinent to ice formation and accreting process as water droplets impinging onto wind turbine blades.

Multiscale modeling of thermal conductivity of high burnup structures in UO 2 fuels

DOE PAGES

Bai, Xian -Ming; Tonks, Michael R.; Zhang, Yongfeng; ...

2015-12-22

The high burnup structure forming at the rim region in UO 2 based nuclear fuel pellets has interesting physical properties such as improved thermal conductivity, even though it contains a high density of grain boundaries and micron-size gas bubbles. To understand this counterintuitive phenomenon, mesoscale heat conduction simulations with inputs from atomistic simulations and experiments were conducted to study the thermal conductivities of a small-grain high burnup microstructure and two large-grain unrestructured microstructures. We concluded that the phonon scattering effects caused by small point defects such as dispersed Xe atoms in the grain interior must be included in order tomore » correctly predict the thermal transport properties of these microstructures. In extreme cases, even a small concentration of dispersed Xe atoms such as 10 -5 can result in a lower thermal conductivity in the large-grain unrestructured microstructures than in the small-grain high burnup structure. The high-density grain boundaries in a high burnup structure act as defect sinks and can reduce the concentration of point defects in its grain interior and improve its thermal conductivity in comparison with its large-grain counterparts. Furthermore, an analytical model was developed to describe the thermal conductivity at different concentrations of dispersed Xe, bubble porosities, and grain sizes. Upon calibration, the model is robust and agrees well with independent heat conduction modeling over a wide range of microstructural parameters.« less

The dwarf galaxy UGC 5272 and its small companion galaxy

NASA Technical Reports Server (NTRS)

Hopp, U.; Schulte-Ladbeck, R. E.

1991-01-01

The present study of optical images and spectroscopy of the dwarf irregular galaxy UGC 5272 notes the presence, at 3.6 kpc, of a small neighboring galaxy which is also of irregular type and has a Holmberg diameter of 0.6 kpc. Attention is given to the possibility that the two galaxies, which are resolved into single stars, may form a physical pair. It is suggested that the blue-to-red supergiant ratio of UGC 5272 is high due to its low metallicity. While its extremely blue colors are suggestive of a recent starburst, the structural parameters of the galaxy are surprisingly normal. The gas contribution to total mass is high.

Application of computational methods to analyse and investigate physical and chemical processes of high-temperature mineralizing of condensed substances in gas stream

NASA Astrophysics Data System (ADS)

Markelov, A. Y.; Shiryaevskii, V. L.; Kudrinskiy, A. A.; Anpilov, S. V.; Bobrakov, A. N.

2017-11-01

A computational method of analysis of physical and chemical processes of high-temperature mineralizing of low-level radioactive waste in gas stream in the process of plasma treatment of radioactive waste in shaft furnaces was introduced. It was shown that the thermodynamic simulation method allows fairly adequately describing the changes in the composition of the pyrogas withdrawn from the shaft furnace at different waste treatment regimes. This offers a possibility of developing environmentally and economically viable technologies and small-sized low-cost facilities for plasma treatment of radioactive waste to be applied at currently operating nuclear power plants.

Occult Breast Cancer: Scintimammography with High-Resolution Breast-specific Gamma Camera in Women at High Risk for Breast Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rachel F. Brem; Jocelyn A. Rapelyea; , Gilat Zisman

2005-08-01

To prospectively evaluate a high-resolution breast-specific gamma camera for depicting occult breast cancer in women at high risk for breast cancer but with normal mammographic and physical examination findings. MATERIALS AND METHODS: Institutional Review Board approval and informed consent were obtained. The study was HIPAA compliant. Ninety-four high-risk women (age range, 36-78 years; mean, 55 years) with normal mammographic (Breast Imaging Reporting and Data System [BI-RADS] 1 or 2) and physical examination findings were evaluated with scintimammography. After injection with 25-30 mCi (925-1110 MBq) of technetium 99m sestamibi, patients were imaged with a high-resolution small-field-of-view breast-specific gamma camera in craniocaudalmore » and mediolateral oblique projections. Scintimammograms were prospectively classified according to focal radiotracer uptake as normal (score of 1), with no focal or diffuse uptake; benign (score of 2), with minimal patchy uptake; probably benign (score of 3), with scattered patchy uptake; probably abnormal (score of 4), with mild focal radiotracer uptake; and abnormal (score of 5), with marked focal radiotracer uptake. Mammographic breast density was categorized according to BI-RADS criteria. Patients with normal scintimammograms (scores of 1, 2, or 3) were followed up for 1 year with an annual mammogram, physical examination, and repeat scintimammography. Patients with abnormal scintimammograms (scores of 4 or 5) underwent ultrasonography (US), and those with focal hypoechoic lesions underwent biopsy. If no lesion was found during US, patients were followed up with scintimammography. Specific pathologic findings were compared with scintimammographic findings. RESULTS: Of 94 women, 78 (83%) had normal scintimammograms (score of 1, 2, or 3) at initial examination and 16 (17%) had abnormal scintimammograms (score of 4 or 5). Fourteen (88%) of the 16 patients had either benign findings at biopsy or no focal abnormality at US; in two (12%) patients, invasive carcinoma was diagnosed at US-guided biopsy (9 mm each at pathologic examination). CONCLUSION: High-resolution breast-specific scintimammography can depict small (<1-cm), mammographically occult, nonpalpable lesions in women at increased risk for breast cancer not otherwise identified at mammography or physical examination.« less

Aeromagnetic Expression of Buried Basaltic Volcanoes Near Yucca Mountain, Nevada

USGS Publications Warehouse

O'Leary, Dennis W.; Mankinen, E.A.; Blakely, R.J.; Langenheim, V.E.; Ponce, D.A.

2002-01-01

A high-resolution aeromagnetic survey has defined a number of small dipolar anomalies indicating the presence of magnetic bodies buried beneath the surface of Crater Flat and the Amargosa Desert. Results of potential-field modeling indicate that isolated, small-volume, highly magnetic bodies embedded within the alluvial deposits of both areas produce the anomalies. Their physical characteristics and the fact that they tend to be aligned along major structural trends provide strong support for the hypothesis that the anomalies reflect buried basaltic volcanic centers. Other, similar anomalies are identified as possible targets for further investigation. High-resolution gravity and ground-magnetic surveys, perhaps along with drilling sources of selected anomalies and radiometric age determinations, can provide valuable constraints in estimating potential volcanic hazard to the potential nuclear waste repository at Yucca Mountain.

Leisure-time physical activity and sciatica: A systematic review and meta-analysis.

PubMed

Shiri, R; Falah-Hassani, K; Viikari-Juntura, E; Coggon, D

2016-11-01

The role of leisure-time physical activity in sciatica is uncertain. This study aimed to assess the association of leisure-time physical activity with lumbar radicular pain and sciatica. Literature searches were conducted in PubMed, Embase, Web of Science, Scopus, Google Scholar and ResearchGate databases from 1964 through August 2015. A random-effects meta-analysis was performed, and heterogeneity and small-study bias were assessed. Ten cohort (N = 82,024 participants), four case-control (N = 9350) and four cross-sectional (N = 10,046) studies qualified for meta-analysis. In comparison with no regular physical activity, high level of physical activity (≥4 times/week) was inversely associated with new onset of lumbar radicular pain or sciatica in a meta-analysis of prospective cohort studies [risk ratio (RR) = 0.88, 95% CI 0.78-0.99, I 2  = 0%, 7 studies, N = 78,065]. The association for moderate level of physical activity (1-3 times/week) was weaker (RR = 0.93, CI 0.82-1.05, I 2  = 0%, 6 studies, N = 69,049), and there was no association with physical activity for at least once/week (RR = 0.99, CI 0.86-1.13, 9 studies, N = 73,008). In contrast, a meta-analysis of cross-sectional studies showed a higher prevalence of lumbar radicular pain or sciatica in participants who exercised at least once/week [prevalence ratio (PR) = 1.29, CI 1.09-1.53, I 2  = 0%, 4 studies, N = 10,046], or 1-3 times/week (PR = 1.34, CI 1.02-1.77, I 2  = 0%, N = 7631) than among inactive participants. There was no evidence of small-study bias. This meta-analysis suggests that moderate to high level of leisure physical activity may have a moderate protective effect against development of lumbar radicular pain. However, a large reduction in risk (>30%) seems unlikely. Leisure-time physical activity may reduce the risk of developing lumbar radicular pain. © 2016 European Pain Federation - EFIC®.

Physical controls on half-hourly, daily, and monthly turbulent flux and energy budget over a high-altitude small lake on the Tibetan Plateau

NASA Astrophysics Data System (ADS)

Wang, Binbin; Ma, Yaoming; Ma, Weiqiang; Su, Zhongbo

2017-02-01

Precise measurements of evaporation and understanding of the physical controls on turbulent heat flux over lakes have fundamental significance for catchment-scale water balance analysis and local-scale climate modeling. The observation and simulation of lake-air turbulent flux processes have been widely carried out, but studies that examine high-altitude lakes on the Tibetan Plateau are still rare, especially for small lakes. An eddy covariance (EC) system, together with a four-component radiation sensor and instruments for measuring water temperature profiles, was set up in a small lake within the Nam Co basin in April 2012 for long-term evaporation and energy budget observations. With the valuable measurements collected during the ice-free periods in 2012 and 2013, the main conclusions are summarized as follows: First, a bulk aerodynamic transfer model (B model), with parameters optimized for the specific wave pattern in the small lake, could provide reliable and consistent results with EC measurements, and B model simulations are suitable for data interpolation due to inadequate footprint or malfunction of the EC instrument. Second, the total evaporation in this small lake (812 mm) is approximately 200 mm larger than that from adjacent Nam Co (approximately 627 mm) during their ice-free seasons. Third, wind speed shows significance at temporal scales of half hourly, whereas water vapor and temperature gradients have higher correlations over temporal scales of daily and monthly in lake-air turbulent heat exchange. Finally, energy stored during April to June is mainly released during September to November, suggesting an energy balance closure value of 0.97.

Facilitating Small-Scale Implementation of Inquiry-Based Teaching: Encounters and Experiences of Experimento Multipliers in One South African Province

ERIC Educational Resources Information Center

Dudu, Washington Takawira

2017-01-01

This paper explores the experiences of 37 physical science high school teachers who participated in a professional development (PD) programme coordinated by three Experimento multipliers. The Experimento programme is a Siemens Stiftung international educational programme aimed at providing didactic and methodological approaches to classroom…

Factors affecting potential for Palmer amaranth (Amaranthus palmeri) suppression by winter rye in Georgia, USA

USDA-ARS?s Scientific Manuscript database

Herbicide resistant Palmer amaranth (Amaranthus palmeri) has rapidly become a dominant weed management issue in agronomic crops of the Southeast US. The small size of Palmer amaranth seeds, relative to other common weeds, provides an opportunity to use physical weed control through high-residue, ro...

Factors affecting potential for Palmer amaranth (Amaranthus palmeri) suppression by winter rye in Georgia, USA

USDA-ARS?s Scientific Manuscript database

Herbicide resistant Palmer amaranth has rapidly become a dominant weed management issue in agronomic crops of the Southeast U. S. The small size of Palmer amaranth seeds, relative to other common weeds, provides an opportunity to use physical weed control through high-biomass, rolled cover crop mul...

In search of the dimensions of an incandescent light bulb filament

NASA Astrophysics Data System (ADS)

Ladino, Luis A.; Rondón, Hermilda S.

2018-05-01

The purpose of this paper is to present and discuss an alternative solution to an experimental problem given to high school students in the XXII Ibero-American Physics Olympiad held by Colombia this year. From the measurements of electric current and potential difference across a small tungsten filament lamp students should find the dimensions of its filament. The results obtained are compared with the ones measured directly. This challenging and low-cost experiment can be easily implemented and carried out in any introductory physics laboratory courses.

Observations and Modelling of Winds and Waves during the Surface Wave Dynamics Experiment. Report 1. Intensive Observation Period IOP-1, 20-31 October 1990

DTIC Science & Technology

1993-04-01

wave buoy provided by SEATEX, Norway (Figure 3). The modified Mills-cross array was designed to provide spatial estimates of the variation in wave, wind... designed for SWADE to examine the wave physics at different spatial and temporal scales, and the usefulness of a nested system. Each grid is supposed to...field specification. SWADE Model This high-resolution grid was designed to simulate the small scale wave physics and to improve and verify the source

Promoting Success in the Physical Sciences: The University of Wisconsin's Physics Learning Program

NASA Astrophysics Data System (ADS)

Nossal, S. M.; Jacob, A. T.

2002-05-01

The Physics Learning Program at the University of Wisconsin-Madison provides small group, academic and mentoring support for students enrolled in algebra-based introductory physics courses. Those students accepted into our program are potentially at-risk academically in their physics course or for feeling isolated at the University. They include, among others, students who have not taken high school physics, returning adults, minority students, students with disabilities, and students with English as a second language. A core component of the program is the peer-lead teaching and mentoring groups that match upper level undergraduate physics majors with students potentially at-risk in introductory physics. The tutors receive ongoing training and supervision throughout the year. The program has expanded over the years to include staff tutors, the majority of whom are scientists who seek additional teaching experience. The Physics Peer Mentor Tutor Program is run in collaboration with a similar chemistry program at the University of Wisconsin's Chemistry Learning Center. We will describe our Physics Learning Programs and discuss some of the challenges, successes, and strategies used to work with our tutors and students.

The effects of a physical activity intervention on employees in small and medium enterprises: a mixed methods study.

PubMed

Edmunds, Sarah; Stephenson, Duncan; Clow, Angela

2013-01-01

Workplaces have potential as a setting for physical activity promotion but evidence of the effectiveness of intervention programmes in small and medium sized enterprises is limited. This paper reports the impact of an intervention which trained existing employees to promote physical activity to their colleagues. Eighty-nine previously low-active employees from 17 small and medium sized organisations participated. A mixed methods evaluation design was used. Quantitative data were collected at baseline and 6 months later using an online questionnaire. Qualitative data from a series of 6 focus groups were analysed. Repeated measures t-tests showed significant increases over time in physical activity, general health rating, satisfaction with life and positive mood states. There were significant decreases in body mass index (BMI), perceived stress, negative mood states and presenteeism. There was no change in absenteeism. Analysis of focus group data provided further insight into the impact of the intervention. Five major themes emerged: awareness of physical activity; sustaining physical activity behaviour change; improved health and well-being; enhanced social networks; and embedding physical activity in the workplace culture. This study shows it is feasible and effective to train employees in small and medium sized enterprises to support their colleagues in physical activity behaviour change.

Primary and High School resources for teachers and students to improve the space physics education in Chile

NASA Astrophysics Data System (ADS)

Morales, P. V.; Pinto, V. A.; Stepanova, M. V.; Valdivia, J. A.

2011-12-01

Primary and High School educational programs in Chile include a wide geophysical section inside the natural sciences and physics courses. Unfortunately, teacher generally have a lack of preparation and knowledge in this field and there is small amount of available didactical material in the native languaje. This implies that in the reality the geophysical topics are ignored year after year in the school rooms. By the preparation of didactic material and web resources in magnetosphere, solar wind and solar topics, in accordance with the official programs of the Chilean Ministry of Education, we are collaborating to the outreach of the space physics in Chile. As the primary diffusion mechanism is the web, we hope that all the spanish talking community in Latin America can benefit from the public teaching resources that we are developing. There are a growing number of space scientist and graduate students volunteering for this endeavour.

Fundamental Physics from Observations of White Dwarf Stars

NASA Astrophysics Data System (ADS)

Bainbridge, M. B.; Barstow, M. A.; Reindl, N.; Barrow, J. D.; Webb, J. K.; Hu, J.; Preval, S. P.; Holberg, J. B.; Nave, G.; Tchang-Brillet, L.; Ayres, T. R.

2017-03-01

Variation in fundamental constants provide an important test of theories of grand unification. Potentially, white dwarf spectra allow us to directly observe variation in fundamental constants at locations of high gravitational potential. We study hot, metal polluted white dwarf stars, combining far-UV spectroscopic observations, atomic physics, atmospheric modelling and fundamental physics, in the search for variation in the fine structure constant. This registers as small but measurable shifts in the observed wavelengths of highly ionized Fe and Ni lines when compared to laboratory wavelengths. Measurements of these shifts were performed by Berengut et al (2013) using high-resolution STIS spectra of G191-B2B, demonstrating the validity of the method. We have extended this work by; (a) using new (high precision) laboratory wavelengths, (b) refining the analysis methodology (incorporating robust techniques from previous studies towards quasars), and (c) enlarging the sample of white dwarf spectra. A successful detection would be the first direct measurement of a gravitational field effect on a bare constant of nature. We describe our approach and present preliminary results.

High school student physics research experience yields positive results

NASA Astrophysics Data System (ADS)

Podolak, K. R.; Walters, M. J.

2016-03-01

All high school students that wish to continue onto college are seeking opportunities to be competitive in the college market. They participate in extra-curricular activities which are seen to foster creativity and the skills necessary to do well in the college environment. In the case of students with an interest in physics, participating in a small scale research project while in high school gives them the hands on experience and ultimately prepares them more for the college experience. SUNY Plattsburgh’s Physics department started a five-week summer program for high school students in 2012. This program has proved not only beneficial for students while in the program, but also as they continue on in their development as scientists/engineers. Independent research, such as that offered by SUNY Plattsburgh’s five-week summer program, offers students a feel and taste of the culture of doing research, and life as a scientist. It is a short-term, risk free way to investigate whether a career in research or a particular scientific field is a good fit.

Small-Size High-Current Generators for X-Ray Backlighting

NASA Astrophysics Data System (ADS)

Chaikovsky, S. A.; Artyomov, A. P.; Zharova, N. V.; Zhigalin, A. S.; Lavrinovich, I. V.; Oreshkin, V. I.; Ratakhin, N. A.; Rousskikh, A. G.; Fedunin, A. V.; Fedushchak, V. F.; Erfort, A. A.

2017-12-01

The paper deals with the soft X-ray backlighting based on the X-pinch as a powerful tool for physical studies of fast processes. Proposed are the unique small-size pulsed power generators operating as a low-inductance capacitor bank. These pulse generators provide the X-pinch-based soft X-ray source (hν = 1-10 keV) of micron size at 2-3 ns pulse duration. The small size and weight of pulse generators allow them to be transported to any laboratory for conducting X-ray backlighting of test objects with micron space resolution and nanosecond exposure time. These generators also allow creating synchronized multi-frame radiographic complexes with frame delay variation in a broad range.

Small-scale fracture toughness of ceramic thin films: the effects of specimen geometry, ion beam notching and high temperature on chromium nitride toughness evaluation

NASA Astrophysics Data System (ADS)

Best, James P.; Zechner, Johannes; Wheeler, Jeffrey M.; Schoeppner, Rachel; Morstein, Marcus; Michler, Johann

2016-12-01

For the implementation of thin ceramic hard coatings into intensive application environments, the fracture toughness is a particularly important material design parameter. Characterisation of the fracture toughness of small-scale specimens has been a topic of great debate, due to size effects, plasticity, residual stress effects and the influence of ion penetration from the sample fabrication process. In this work, several different small-scale fracture toughness geometries (single-beam cantilever, double-beam cantilever and micro-pillar splitting) were compared, fabricated from a thin physical vapour-deposited ceramic film using a focused ion beam source, and then the effect of the gallium-milled notch on mode I toughness quantification investigated. It was found that notching using a focused gallium source influences small-scale toughness measurements and can lead to an overestimation of the fracture toughness values for chromium nitride (CrN) thin films. The effects of gallium ion irradiation were further studied by performing the first small-scale high-temperature toughness measurements within the scanning electron microscope, with the consequence that annealing at high temperatures allows for diffusion of the gallium to grain boundaries promoting embrittlement in small-scale CrN samples. This work highlights the sensitivity of some materials to gallium ion penetration effects, and the profound effect that it can have on fracture toughness evaluation.

Forward and small-x QCD physics results from CMS experiment at LHC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cerci, Deniz Sunar, E-mail: deniz.sunar.cerci@cern.ch

2016-03-25

The Compact Muon Solenoid (CMS) is one of the two large, multi-purpose experiments at the Large Hadron Collider (LHC) at CERN. During the Run I Phase a large pp collision dataset has been collected and the CMS collaboration has explored measurements that shed light on a new era. Forward and small-x quantum chromodynamics (QCD) physics measurements with CMS experiment covers a wide range of physics subjects. Some of highlights in terms of testing the very low-x QCD, underlying event and multiple interaction characteristics, photon-mediated processes, jets with large rapidity separation at high pseudo-rapidities and the inelastic proton-proton cross section dominatedmore » by diffractive interactions are presented. Results are compared to Monte Carlo (MC) models with different parameter tunes for the description of the underlying event and to perturbative QCD calculations. The prominent role of multi-parton interactions has been confirmed in the semihard sector but no clear deviation from the standard Dglap parton evolution due to Bfkl has been observed. An outlook to the prospects at 13 TeV is given.« less

Job Strain in Physical Therapists

PubMed Central

Campo, Marc A.; Weiser, Sherri; Koenig, Karen L.

2009-01-01

Background: Job stress has been associated with poor outcomes. In focus groups and small-sample surveys, physical therapists have reported high levels of job stress. Studies of job stress in physical therapy with larger samples are needed. Objective: The purposes of this study were: (1) to determine the levels of psychological job demands and job control reported by physical therapists in a national sample, (2) to compare those levels with national norms, and (3) to determine whether high demands, low control, or a combination of both (job strain) increases the risk for turnover or work-related pain. Design: This was a prospective cohort study with a 1-year follow-up period. Methods: Participants were randomly selected members of the American Physical Therapy Association (n=882). Exposure assessments included the Job Content Questionnaire (JCQ), a commonly used instrument for evaluation of the psychosocial work environment. Outcomes included job turnover and work-related musculoskeletal disorders. Results: Compared with national averages, the physical therapists reported moderate job demands and high levels of job control. About 16% of the therapists reported changing jobs during follow-up. Risk factors for turnover included high job demands, low job control, job strain, female sex, and younger age. More than one half of the therapists reported work-related pain. Risk factors for work-related pain included low job control and job strain. Limitations: The JCQ measures only limited dimensions of the psychosocial work environment. All data were self-reported and subject to associated bias. Conclusions: Physical therapists’ views of their work environments were positive, including moderate levels of demands and high levels of control. Those therapists with high levels of demands and low levels of control, however, were at increased risk for both turnover and work-related pain. Physical therapists should consider the psychosocial work environment, along with other factors, when choosing a job. PMID:19608632

Health Impacts of the Built Environment: Within-Urban Variability in Physical Inactivity, Air Pollution, and Ischemic Heart Disease Mortality

PubMed Central

Hankey, Steve; Brauer, Michael

2011-01-01

Background: Physical inactivity and exposure to air pollution are important risk factors for death and disease globally. The built environment may influence exposures to these risk factors in different ways and thus differentially affect the health of urban populations. Objective: We investigated the built environment’s association with air pollution and physical inactivity, and estimated attributable health risks. Methods: We used a regional travel survey to estimate within-urban variability in physical inactivity and home-based air pollution exposure [particulate matter with aerodynamic diameter ≤ 2.5 μm (PM2.5), nitrogen oxides (NOx), and ozone (O3)] for 30,007 individuals in southern California. We then estimated the resulting risk for ischemic heart disease (IHD) using literature-derived dose–response values. Using a cross-sectional approach, we compared estimated IHD mortality risks among neighborhoods based on “walkability” scores. Results: The proportion of physically active individuals was higher in high- versus low-walkability neighborhoods (24.9% vs. 12.5%); however, only a small proportion of the population was physically active, and between-neighborhood variability in estimated IHD mortality attributable to physical inactivity was modest (7 fewer IHD deaths/100,000/year in high- vs. low-walkability neighborhoods). Between-neighborhood differences in estimated IHD mortality from air pollution were comparable in magnitude (9 more IHD deaths/100,000/year for PM2.5 and 3 fewer IHD deaths for O3 in high- vs. low-walkability neighborhoods), suggesting that population health benefits from increased physical activity in high-walkability neighborhoods may be offset by adverse effects of air pollution exposure. Policy implications: Currently, planning efforts mainly focus on increasing physical activity through neighborhood design. Our results suggest that differences in population health impacts among neighborhoods are similar in magnitude for air pollution and physical activity. Thus, physical activity and exposure to air pollution are critical aspects of planning for cleaner, health-promoting cities. PMID:22004949

Health impacts of the built environment: within-urban variability in physical inactivity, air pollution, and ischemic heart disease mortality.

PubMed

Hankey, Steve; Marshall, Julian D; Brauer, Michael

2012-02-01

Physical inactivity and exposure to air pollution are important risk factors for death and disease globally. The built environment may influence exposures to these risk factors in different ways and thus differentially affect the health of urban populations. We investigated the built environment's association with air pollution and physical inactivity, and estimated attributable health risks. We used a regional travel survey to estimate within-urban variability in physical inactivity and home-based air pollution exposure [particulate matter with aerodynamic diameter ≤ 2.5 μm (PM2.5), nitrogen oxides (NOx), and ozone (O3)] for 30,007 individuals in southern California. We then estimated the resulting risk for ischemic heart disease (IHD) using literature-derived dose-response values. Using a cross-sectional approach, we compared estimated IHD mortality risks among neighborhoods based on "walkability" scores. The proportion of physically active individuals was higher in high- versus low-walkability neighborhoods (24.9% vs. 12.5%); however, only a small proportion of the population was physically active, and between-neighborhood variability in estimated IHD mortality attributable to physical inactivity was modest (7 fewer IHD deaths/100,000/year in high- vs. low-walkability neighborhoods). Between-neighborhood differences in estimated IHD mortality from air pollution were comparable in magnitude (9 more IHD deaths/100,000/year for PM2.5 and 3 fewer IHD deaths for O3 in high- vs. low-walkability neighborhoods), suggesting that population health benefits from increased physical activity in high-walkability neighborhoods may be offset by adverse effects of air pollution exposure. Currently, planning efforts mainly focus on increasing physical activity through neighborhood design. Our results suggest that differences in population health impacts among neighborhoods are similar in magnitude for air pollution and physical activity. Thus, physical activity and exposure to air pollution are critical aspects of planning for cleaner, health-promoting cities.

Does a lack of physical activity explain the rheumatoid arthritis lipid profile?

PubMed

AbouAssi, Hiba; Connelly, Margery A; Bateman, Lori A; Tune, K Noelle; Huebner, Janet L; Kraus, Virginia B; Winegar, Deborah A; Otvos, James D; Kraus, William E; Huffman, Kim M

2017-02-10

In rheumatoid arthritis (RA), cardiovascular risk is associated with paradoxical reductions in total cholesterol, low density lipoprotein-cholesterol (LDL-C), and high density lipoprotein-cholesterol (HDL-C). Concentrations of small LDL (LDL-P) and HDL (HDL-P) particles are also reduced with increased inflammation and disease activity in RA patients. Here we sought to identify which measure(s) of inflammation, disease activity and cardiometabolic risk contribute most to the RA-associated lipoprotein profile. NMR lipoprotein measurements were obtained for individuals with RA (n = 50) and age-, gender-, and body mass index (BMI)-matched controls (n = 39). Groups were compared using 39 matched pairs with 11 additional subjects used in RA only analyses. Among RA patients, relationships were determined for lipoprotein parameters with measures of disease activity, disability, pain, inflammation, body composition, insulin sensitivity and exercise. Percentage of time spent in basal activity (<1 metabolic equivalent) and exercise (≥3 metabolic equivalents) were objectively-determined. Subjects with RA had fewer total and small LDL-P as well as larger LDL and HDL size (P < 0.05). Among RA patients, pain and disability were associated with fewer small HDL-P (P < 0.05), while interleukin (IL)-6, IL-18, and TNF-α were associated with LDL size (P < 0.05). BMI, waist circumference, abdominal visceral adiposity and insulin resistance were associated with more total and small LDL-P, fewer large HDL-P, and a reduction in HDL size (P < 0.05). Most similar to the RA lipoprotein profile, more basal activity (minimal physical activity) and less exercise time were associated with fewer small LDL-P and total and small HDL-P (P < 0.05). The RA-associated lipoprotein profile is associated with a lack of physical activity. As this was a cross-sectional investigation and not an intervention and was performed from 2008-13, this study was not registered in clinicaltrials.gov.

How to double the number of undergraduate physics majors

NASA Astrophysics Data System (ADS)

Kopp, Sacha

2015-03-01

Many colleges and universities around the country have a solid physics program that prepares students bound for graduate physics study. For a variety of reasons, the number of students choosing to major in physics may be small, typically <1% of the student body. When compared to other majors, this population is experiencing negligible growth. I will describe a campaign launched while at the University of Texas at Austin aimed at recruiting and retention of majors. This campaign includes actual programmatic changes in the curriculum and instruction of majors. Additionally, it includes a direct marketing campaign that attempted to change student attitudes about physics and its relation to their current major. Finally, it includes a program to reach out to local high schools and engage students in a discussion about their career choices before they apply for college. I will share some numerical and attitudinal data that suggests positive changes in the student population.

Small-scale Detonation Velocity Measurement of Select CL-20 Cocrystals

NASA Astrophysics Data System (ADS)

Vuppuluri, Vasant; Gunduz, I. Emre; Son, Steven F.

2017-06-01

The challenge of developing novel energetic materials makes cocrystallization using existing energetic molecules useful. Cocrystallization of CL-20 with other high explosives such as HMX has been demonstrated previously to yield novel energetic materials and may have favorable detonation performance. However, detonation performance characterization of these cocrystals is challenging due to limited availability of material. Also, the contribution of bonding energy between coformers contained within the cocrystal is not well-understood. We present the comparison of steady detonation velocities of CL-20 cocrystals to their corresponding physical mixtures using microwave interferometry. With less than 1.5 g of the cocrystal material contained within 6.52 mm diameter charges, shot-to-shot variation in detonation velocity of only about 100 m/s are achievable with this technique. This variation is adequate to resolve relatively small differences between physical mixed explosive molecules and cocrystals.

On Efficient Multigrid Methods for Materials Processing Flows with Small Particles

NASA Technical Reports Server (NTRS)

Thomas, James (Technical Monitor); Diskin, Boris; Harik, VasylMichael

2004-01-01

Multiscale modeling of materials requires simulations of multiple levels of structural hierarchy. The computational efficiency of numerical methods becomes a critical factor for simulating large physical systems with highly desperate length scales. Multigrid methods are known for their superior efficiency in representing/resolving different levels of physical details. The efficiency is achieved by employing interactively different discretizations on different scales (grids). To assist optimization of manufacturing conditions for materials processing with numerous particles (e.g., dispersion of particles, controlling flow viscosity and clusters), a new multigrid algorithm has been developed for a case of multiscale modeling of flows with small particles that have various length scales. The optimal efficiency of the algorithm is crucial for accurate predictions of the effect of processing conditions (e.g., pressure and velocity gradients) on the local flow fields that control the formation of various microstructures or clusters.

Cosmic Visions Dark Energy: Small Projects Portfolio

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dawson, Kyle; Frieman, Josh; Heitmann, Katrin

Understanding cosmic acceleration is one of the key science drivers for astrophysics and high-energy physics in the coming decade (2014 P5 Report). With the Large Synoptic Survey Telescope (LSST) and the Dark Energy Spectroscopic Instrument (DESI) and other new facilities beginning operations soon, we are entering an exciting phase during which we expect an order of magnitude improvement in constraints on dark energy and the physics of the accelerating Universe. This is a key moment for a matching Small Projects portfolio that can (1) greatly enhance the science reach of these flagship projects, (2) have immediate scientific impact, and (3)more » lay the groundwork for the next stages of the Cosmic Frontier Dark Energy program. In this White Paper, we outline a balanced portfolio that can accomplish these goals through a combination of observational, experimental, and theory and simulation efforts.« less

Should we trust build-up/wash-off water quality models at the scale of urban catchments?

PubMed

Bonhomme, Céline; Petrucci, Guido

2017-01-01

Models of runoff water quality at the scale of an urban catchment usually rely on build-up/wash-off formulations obtained through small-scale experiments. Often, the physical interpretation of the model parameters, valid at the small-scale, is transposed to large-scale applications. Testing different levels of spatial variability, the parameter distributions of a water quality model are obtained in this paper through a Monte Carlo Markov Chain algorithm and analyzed. The simulated variable is the total suspended solid concentration at the outlet of a periurban catchment in the Paris region (2.3 km 2 ), for which high-frequency turbidity measurements are available. This application suggests that build-up/wash-off models applied at the catchment-scale do not maintain their physical meaning, but should be considered as "black-box" models. Copyright © 2016 Elsevier Ltd. All rights reserved.

Galaxy And Mass Assembly (GAMA): the signatures of galaxy interactions as viewed from small scale galaxy clustering

NASA Astrophysics Data System (ADS)

Gunawardhana, M. L. P.; Norberg, P.; Zehavi, I.; Farrow, D. J.; Loveday, J.; Hopkins, A. M.; Davies, L. J. M.; Wang, L.; Alpaslan, M.; Bland-Hawthorn, J.; Brough, S.; Holwerda, B. W.; Owers, M. S.; Wright, A. H.

2018-06-01

Statistical studies of galaxy-galaxy interactions often utilise net change in physical properties of progenitors as a function of the separation between their nuclei to trace both the strength and the observable timescale of their interaction. In this study, we use two-point auto, cross and mark correlation functions to investigate the extent to which small-scale clustering properties of star forming galaxies can be used to gain physical insight into galaxy-galaxy interactions between galaxies of similar optical brightness and stellar mass. The Hα star formers, drawn from the highly spatially complete Galaxy And Mass Assembly (GAMA) survey, show an increase in clustering on small separations. Moreover, the clustering strength shows a strong dependence on optical brightness and stellar mass, where (1) the clustering amplitude of optically brighter galaxies at a given separation is larger than that of optically fainter systems, (2) the small scale clustering properties (e.g. the strength, the scale at which the signal relative to the fiducial power law plateaus) of star forming galaxies appear to differ as a function of increasing optical brightness of galaxies. According to cross and mark correlation analyses, the former result is largely driven by the increased dust content in optically bright star forming galaxies. The latter could be interpreted as evidence of a correlation between interaction-scale and optical brightness of galaxies, where physical evidence of interactions between optically bright star formers, likely hosted within relatively massive halos, persist over larger separations than those between optically faint star formers.

The physical characteristics of human proteins in different biological functions.

PubMed

Wang, Tengjiao; Tang, Hailin

2017-01-01

The physical properties of gene products are the foundation of their biological functions. In this study, we systematically explored relationships between physical properties and biological functions. The physical properties including origin time, evolution pressure, mRNA and protein stability, molecular weight, hydrophobicity, acidity/alkaline, amino acid compositions, and chromosome location. The biological functions are defined from 4 aspects: biological process, molecular function, cellular component and cell/tissue/organ expression. We found that the proteins associated with basic material and energy metabolism process originated earlier, while the proteins associated with immune, neurological system process etc. originated later. Tissues may have a strong influence on evolution pressure. The proteins associated with energy metabolism are double-stable. Immune and peripheral cell proteins tend to be mRNA stable/protein unstable. There are very few function items with double-unstable of mRNA and protein. The proteins involved in the cell adhesion tend to consist of large proteins with high proportion of small amino acids. The proteins of organic acid transport, neurological system process and amine transport have significantly high hydrophobicity. Interestingly, the proteins involved in olfactory receptor activity tend to have high frequency of aromatic, sulfuric and hydroxyl amino acids.

The physical characteristics of human proteins in different biological functions

PubMed Central

Tang, Hailin

2017-01-01

The physical properties of gene products are the foundation of their biological functions. In this study, we systematically explored relationships between physical properties and biological functions. The physical properties including origin time, evolution pressure, mRNA and protein stability, molecular weight, hydrophobicity, acidity/alkaline, amino acid compositions, and chromosome location. The biological functions are defined from 4 aspects: biological process, molecular function, cellular component and cell/tissue/organ expression. We found that the proteins associated with basic material and energy metabolism process originated earlier, while the proteins associated with immune, neurological system process etc. originated later. Tissues may have a strong influence on evolution pressure. The proteins associated with energy metabolism are double-stable. Immune and peripheral cell proteins tend to be mRNA stable/protein unstable. There are very few function items with double-unstable of mRNA and protein. The proteins involved in the cell adhesion tend to consist of large proteins with high proportion of small amino acids. The proteins of organic acid transport, neurological system process and amine transport have significantly high hydrophobicity. Interestingly, the proteins involved in olfactory receptor activity tend to have high frequency of aromatic, sulfuric and hydroxyl amino acids. PMID:28459865

Shifting the Physical Inactivity Curve Worldwide by Closing the Gender Gap.

PubMed

Mielke, Grégore I; da Silva, Inacio Crochemore M; Kolbe-Alexander, Tracy L; Brown, Wendy J

2018-02-01

The aims of this study were to (i) examine gender differences in physical inactivity in countries with different levels of Human Development Index (HDI); and (ii) assess whether small changes in the prevalence of inactivity in women could achieve the World Health Organization's (WHO) global inactivity target. Data on inactivity were extracted for 142 countries for the year 2010 from the WHO Data Repository. Data for HDI were obtained for the year 2010 from the United Nations Development Program. Absolute and relative gender differences were calculated for countries according to four HDI categories. The potential effects of increasing women's activity levels on achievement of the WHO physical inactivity target were computed. Overall inactivity prevalence was higher in women (27%) than in men (20%). Women were more inactive than men in all except eight countries. Absolute gender differences [median 7.5% (range -10.1 to 33.2)] did not vary by HDI category, but there was a small negative correlation between relative gender difference in inactivity and HDI (rho -0.19; p = 0.02), which was mostly influenced by three outlier countries with low HDI. A decrease in inactivity levels of 4.8% points among women across the world would achieve the WHO target of reducing global levels of inactivity by 10%. Gender differences in the prevalence of physical inactivity were highly variable, both within and across categories of HDI. Interventions which result in small changes in inactivity prevalence in women would achieve the 2025 WHO global target for inactivity, without any change to the prevalence in men.

Multisensor sampling of pelagic ecosystem variables in a coastal environment to estimate zooplankton grazing impact

NASA Astrophysics Data System (ADS)

Sutton, Tracey; Hopkins, Thomas; Remsen, Andrew; Burghart, Scott

2001-01-01

Sampling was conducted on the west Florida continental shelf ecosystem modeling site to estimate zooplankton grazing impact on primary production. Samples were collected with the high-resolution sampler, a towed array bearing electronic and optical sensors operating in tandem with a paired net/bottle verification system. A close biological-physical coupling was observed, with three main plankton communities: 1. a high-density inshore community dominated by larvaceans coincident with a salinity gradient; 2. a low-density offshore community dominated by small calanoid copepods coincident with the warm mixed layer; and 3. a high-density offshore community dominated by small poecilostomatoid and cyclopoid copepods and ostracods coincident with cooler, sub-pycnocline oceanic water. Both high-density communities were associated with relatively turbid water. Applying available grazing rates from the literature to our abundance data, grazing pressure mirrored the above bio-physical pattern, with the offshore sub-pycnocline community contributing ˜65% of grazing pressure despite representing only 19% of the total volume of the transect. This suggests that grazing pressure is highly localized, emphasizing the importance of high-resolution sampling to better understand plankton dynamics. A comparison of our grazing rate estimates with primary production estimates suggests that mesozooplankton do not control the fate of phytoplankton over much of the area studied (<5% grazing of daily primary production), but "hot spots" (˜25-50% grazing) do occur which may have an effect on floral composition.

Setup for potential bias experiments on the Saha Institute of Nuclear Physics tokamak

NASA Astrophysics Data System (ADS)

Ghosh, J.; Pal, R.; Chattopadhyay, P. K.

1999-12-01

An experimental setup for studying the influence of the radial electric field on very low qa plasma on the Saha Institute of Nuclear Physics tokamak is presented. A high current, high voltage pulsed power supply, using a semiconductor controlled rectifier (SCR) as a dc switch is developed and used to bias a tungsten electrode inserted inside the plasma. The electrode's exposed length and its position inside the plasma are controlled by a double bellows assembly to optimize the electrode-exposed length. We show that using the force commutation method to turn the SCR off to get the power pulse desired has good potential for carrying out similar kinds of studies, especially in a low budget small tokamak.

Morphometric analysis of Russian Plain's small lakes on the base of accurate digital bathymetric models

NASA Astrophysics Data System (ADS)

Naumenko, Mikhail; Guzivaty, Vadim; Sapelko, Tatiana

2016-04-01

Lake morphometry refers to physical factors (shape, size, structure, etc) that determine the lake depression. Morphology has a great influence on lake ecological characteristics especially on water thermal conditions and mixing depth. Depth analyses, including sediment measurement at various depths, volumes of strata and shoreline characteristics are often critical to the investigation of biological, chemical and physical properties of fresh waters as well as theoretical retention time. Management techniques such as loading capacity for effluents and selective removal of undesirable components of the biota are also dependent on detailed knowledge of the morphometry and flow characteristics. During the recent years a lake bathymetric surveys were carried out by using echo sounder with a high bottom depth resolution and GPS coordinate determination. Few digital bathymetric models have been created with 10*10 m spatial grid for some small lakes of Russian Plain which the areas not exceed 1-2 sq. km. The statistical characteristics of the depth and slopes distribution of these lakes calculated on an equidistant grid. It will provide the level-surface-volume variations of small lakes and reservoirs, calculated through combination of various satellite images. We discuss the methodological aspects of creating of morphometric models of depths and slopes of small lakes as well as the advantages of digital models over traditional methods.

In Search of the Dimensions of an Incandescent Light Bulb Filament

ERIC Educational Resources Information Center

Ladino, Luis A.; Rondón, Hermilda S.

2018-01-01

The purpose of this paper is to present and discuss an alternative solution to an experimental problem given to high school students in the XXII Ibero-American Physics Olympiad held by Colombia this year. From the measurements of electric current and potential difference across a small tungsten filament lamp students should find the dimensions of…

High-resolution tyramide-FISH mapping of markers tightly linked to the male-fertility restoration (Ms) locus of onion

USDA-ARS?s Scientific Manuscript database

Fluorescence in situ hybridization (FISH) has not been readily exploited for physical mapping of molecular markers in plants due to the technical challenge to visualize small single-copy probes. Signal amplification using tyramide (tyr) FISH can increase sensitivity up to 100 fold. We used tyr-FISH ...

Developing Outdoor and Adventurous Activities for Co-Existence and Reconciliation in Israel: An Anglo-German Approach

ERIC Educational Resources Information Center

Stidder, Gary; Haasner, Adrian

2007-01-01

Conflict resolution between different social groups is an issue that has continued to gain high profile news coverage both nationally and in a global context. In this respect, it has been shown that carefully designed and managed physical activity programmes can make a small but nonetheless invaluable contribution to reconciliation and…

Implicit Space-Time Conservation Element and Solution Element Schemes

NASA Technical Reports Server (NTRS)

Chang, Sin-Chung; Himansu, Ananda; Wang, Xiao-Yen

1999-01-01

Artificial numerical dissipation is in important issue in large Reynolds number computations. In such computations, the artificial dissipation inherent in traditional numerical schemes can overwhelm the physical dissipation and yield inaccurate results on meshes of practical size. In the present work, the space-time conservation element and solution element method is used to construct new and accurate implicit numerical schemes such that artificial numerical dissipation will not overwhelm physical dissipation. Specifically, these schemes have the property that numerical dissipation vanishes when the physical viscosity goes to zero. These new schemes therefore accurately model the physical dissipation even when it is extremely small. The new schemes presented are two highly accurate implicit solvers for a convection-diffusion equation. The two schemes become identical in the pure convection case, and in the pure diffusion case. The implicit schemes are applicable over the whole Reynolds number range, from purely diffusive equations to convection-dominated equations with very small viscosity. The stability and consistency of the schemes are analysed, and some numerical results are presented. It is shown that, in the inviscid case, the new schemes become explicit and their amplification factors are identical to those of the Leapfrog scheme. On the other hand, in the pure diffusion case, their principal amplification factor becomes the amplification factor of the Crank-Nicolson scheme.

Who Is the Competent Physics Student? A Study of Students' Positions and Social Interaction in Small-Group Discussions

ERIC Educational Resources Information Center

Due, Karin

2014-01-01

This article describes a study which explored the social interaction and the reproduction and challenge of gendered discourses in small group discussions in physics. Data for the study consisted of video recordings of eight upper secondary school groups solving physics problems and 15 audiotaped individual interviews with participating students.…

Rippled Quasiperpendicular Shock Observed by the Magnetospheric Multiscale Spacecraft.

PubMed

Johlander, A; Schwartz, S J; Vaivads, A; Khotyaintsev, Yu V; Gingell, I; Peng, I B; Markidis, S; Lindqvist, P-A; Ergun, R E; Marklund, G T; Plaschke, F; Magnes, W; Strangeway, R J; Russell, C T; Wei, H; Torbert, R B; Paterson, W R; Gershman, D J; Dorelli, J C; Avanov, L A; Lavraud, B; Saito, Y; Giles, B L; Pollock, C J; Burch, J L

2016-10-14

Collisionless shock nonstationarity arising from microscale physics influences shock structure and particle acceleration mechanisms. Nonstationarity has been difficult to quantify due to the small spatial and temporal scales. We use the closely spaced (subgyroscale), high-time-resolution measurements from one rapid crossing of Earth's quasiperpendicular bow shock by the Magnetospheric Multiscale (MMS) spacecraft to compare competing nonstationarity processes. Using MMS's high-cadence kinetic plasma measurements, we show that the shock exhibits nonstationarity in the form of ripples.

Microscale Heat Transfer Enhancement using Spinodal Decomposition of Binary Liquid Mixtures: A Collaborative Modeling/Experimental Approach

DTIC Science & Technology

2013-09-01

heat transfer coefficients due to the high heat of vapor- ization. Many authors ([ Mudawar (2001)], [ Mudawar and Bowers (1999)] and [Kandlikar (2005...Letters, 95, (2005), 1. [Rosales and Meneveau (2006)] C. Rosales and C. Meneveau. Physics of Fluids, 18, (2006), 075104. [ Mudawar and Bowers (1999)] I... Mudawar and M.B. Bowers, Ultra-high crit- ical heat flux (CHF) for subcooled water flow boiling-I: CHF data and parametric effects for small

Rippled Quasiperpendicular Shock Observed by the Magnetospheric Multiscale Spacecraft

NASA Technical Reports Server (NTRS)

Johlander, A.; Schwartz, S. J.; Vaivads, A.; Khotyaintsev, Yu. V.; Gingell, I.; Peng, I. B.; Markidis, S.; Lindqvist, P.-A.; Ergun, R. E.; Marklund, G. T.;

A Low-Power Thermal-Based Sensor System for Low Air Flow Detection

PubMed Central

Arifuzzman, AKM; Haider, Mohammad Rafiqul; Allison, David B.

2016-01-01

Being able to rapidly detect a low air flow rate with high accuracy is essential for various applications in the automotive and biomedical industries. We have developed a thermal-based low air flow sensor with a low-power sensor readout for biomedical applications. The thermal-based air flow sensor comprises a heater and three pairs of temperature sensors that sense temperature differences due to laminar air flow. The thermal-based flow sensor was designed and simulated by using laminar flow, heat transfer in solids and fluids physics in COMSOL MultiPhysics software. The proposed sensor can detect air flow as low as 0.0064 m/sec. The readout circuit is based on a current- controlled ring oscillator in which the output frequency of the ring oscillator is proportional to the temperature differences of the sensors. The entire readout circuit was designed and simulated by using a 130-nm standard CMOS process. The sensor circuit features a small area and low-power consumption of about 22.6 µW with an 800 mV power supply. In the simulation, the output frequency of the ring oscillator and the change in thermistor resistance showed a high linearity with an R2 value of 0.9987. The low-power dissipation, high linearity and small dimensions of the proposed flow sensor and circuit make the system highly suitable for biomedical applications. PMID:28435186

Developmental trajectories of physical aggression: prediction of overt and covert antisocial behaviors from self- and mothers' reports

PubMed Central

Di Giunta, Laura; Pastorelli, Concetta; Eisenberg, Nancy; Gerbino, Maria; Castellani, Valeria; Bombi, Anna Silvia

2010-01-01

Physical aggression declines for the majority of children from preschool to elementary school. Although this desistance generally continues during adolescence and early adulthood, a small group of children maintain a high level of physical aggression over time and develop other serious overt and covert antisocial behaviors. Typically, researchers have examined relations of developmental changes in physical aggression to later violence with teachers' or mothers' reports on surveys. Little is known about the degree to which children's self-reported physical aggression predicts later antisocial behavior. The longitudinal study in this article had a staggered, multiple cohort design. Measures of physical aggression were collected through self- and mother reports from age 11–14 years, which were used to construct trajectory groups (attrition was 6 and 14% from age 11–14, respectively, for self- and mother reports). Overt and covert antisocial behaviors were self-reported at age 18–19 years (attrition was 36% from age 11 to 18–19). Four trajectory groups (low stable, 11%; moderate-low declining, 34%; moderate declining, 39%; high stable, 16%) were identified from self-reports, whereas three trajectories (low declining, 33%; moderate declining, 49%; high stable, 18%) were identified from mothers' ratings. We examined the prediction of overt and covert antisocial behaviors in early adulthood from the high stable and the moderate declining trajectories. According to both informants, higher probability of belonging to the high stable group was associated with higher overt and covert antisocial behavior, whereas higher probability of belonging to the moderate declining group was associated with higher covert antisocial behavior. Our results support the value of children's as well as mothers' reports of children's aggression for predicting different types of serious antisocial behavior in adulthood. PMID:20878197

Developmental trajectories of physical aggression: prediction of overt and covert antisocial behaviors from self- and mothers' reports.

PubMed

Di Giunta, Laura; Pastorelli, Concetta; Eisenberg, Nancy; Gerbino, Maria; Castellani, Valeria; Bombi, Anna Silvia

2010-12-01

Physical aggression declines for the majority of children from preschool to elementary school. Although this desistance generally continues during adolescence and early adulthood, a small group of children maintain a high level of physical aggression over time and develop other serious overt and covert antisocial behaviors. Typically, researchers have examined relations of developmental changes in physical aggression to later violence with teachers' or mothers' reports on surveys. Little is known about the degree to which children's self-reported physical aggression predicts later antisocial behavior. The longitudinal study in this article had a staggered, multiple cohort design. Measures of physical aggression were collected through self- and mother reports from age 11-14 years, which were used to construct trajectory groups (attrition was 6 and 14% from age 11-14, respectively, for self- and mother reports). Overt and covert antisocial behaviors were self-reported at age 18-19 years (attrition was 36% from age 11 to 18-19). Four trajectory groups (low stable, 11%; moderate-low declining, 34%; moderate declining, 39%; high stable, 16%) were identified from self-reports, whereas three trajectories (low declining, 33%; moderate declining, 49%; high stable, 18%) were identified from mothers' ratings. We examined the prediction of overt and covert antisocial behaviors in early adulthood from the high stable and the moderate declining trajectories. According to both informants, higher probability of belonging to the high stable group was associated with higher overt and covert antisocial behavior, whereas higher probability of belonging to the moderate declining group was associated with higher covert antisocial behavior. Our results support the value of children's as well as mothers' reports of children's aggression for predicting different types of serious antisocial behavior in adulthood.

Microelectromechanical systems for experimental physics and optical telecommunications

NASA Astrophysics Data System (ADS)

Aksyuk, Vladimir Anatolyevich

1999-12-01

Micro-Electro-Mechanical Systems (MEMS) are an emerging technology, which, when applied to the field of physical sensors, offers not only an obvious advantage of being small and cheap, but more importantly, provides some unique experimental opportunities. These are based on the way physical properties scale with decreasing size. This thesis discusses these basic principles and corresponding advantages and limitations of MEMS technology and presents several experiments in which micromachines are used to do physical measurements that could not be done before. Three types of micromechanical magnetometers are demonstrated. When compared to the state of the art traditional techniques they show greater sensitivity, faster response and can be applied over a wider range of experimental conditions. The high-Q micromechanical torsional oscillator magnetometer is used to observe mesoscopic vortex physics, including single flux lines penetrating into a type-II superconductor just above the first critical field. The Faraday balance ``Trampoline'' magnetometer combines high sensitivity, high bandwidth and can be operated in a wide temperature range. It is used in both high pulsed magnetic fields to record deHaas-vanAlphen oscillations and in DC magnetic fields for magnetization measurements at temperatures down to 100mK. The high sensitivity DC torque magnetometer offers yet higher sensitivity and can be used for a variety of magnetization measurements. Several other MEMS devices for physics and telecommunications applications are presented, including a micromachined near field scanning optical microscope, MEMS fiberoptic switches and large-area large-angle scanners. They provide examples of complex functionality that can be achieved with micromechanics by combining sensors with inherently low-power electrostatic actuators. The optically powered optical power limiter demonstrates the possibility of operating MEMS with optical rather than electrical power.

Harmony in the small-world

NASA Astrophysics Data System (ADS)

Marchiori, Massimo; Latora, Vito

2000-10-01

The small-world phenomenon, popularly known as six degrees of separation, has been mathematically formalized by Watts and Strogatz in a study of the topological properties of a network. Small-world networks are defined in terms of two quantities: they have a high clustering coefficient C like regular lattices and a short characteristic path length L typical of random networks. Physical distances are of fundamental importance in applications to real cases; nevertheless, this basic ingredient is missing in the original formulation. Here, we introduce a new concept, the connectivity length D, that gives harmony to the whole theory. D can be evaluated on a global and on a local scale and plays in turn the role of L and 1/ C. Moreover, it can be computed for any metrical network and not only for the topological cases. D has a precise meaning in terms of information propagation and describes in a unified way, both the structural and the dynamical aspects of a network: small-worlds are defined by a small global and local D, i.e., by a high efficiency in propagating information both on a local and global scale. The neural system of the nematode C. elegans, the collaboration graph of film actors, and the oldest US subway system, can now be studied also as metrical networks and are shown to be small-worlds.

Colloidal properties of sodium caseinate-stabilized nanoemulsions prepared by a combination of a high-energy homogenization and evaporative ripening methods.

PubMed

Montes de Oca-Ávalos, J M; Candal, R J; Herrera, M L

2017-10-01

Nanoemulsions stabilized by sodium caseinate (NaCas) were prepared using a combination of a high-energy homogenization and evaporative ripening methods. The effects of protein concentration and sucrose addition on physical properties were analyzed by dynamic light scattering (DLS), Turbiscan analysis, confocal laser scanning microscopy (CLSM) and small angle X-ray scattering (SAXS). Droplets sizes were smaller (~100nm in diameter) than the ones obtained by other methods (200 to 2000nm in diameter). The stability behavior was also different. These emulsions were not destabilized by creaming. As droplets were so small, gravitational forces were negligible. On the contrary, when they showed destabilization the main mechanism was flocculation. Stability of nanoemulsions increased with increasing protein concentrations. Nanoemulsions with 3 or 4wt% NaCas were slightly turbid systems that remained stable for at least two months. According to SAXS and Turbiscan results, aggregates remained in the nano range showing small tendency to aggregation. In those systems, interactive forces were weak due to the small diameter of flocs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dust-obscured Galaxies in the Local Universe

NASA Astrophysics Data System (ADS)

Hwang, Ho Seong; Geller, Margaret J.

2013-06-01

We use Wide-field Infrared Survey Explorer (WISE), AKARI, and Galaxy Evolution Explorer (GALEX) data to select local analogs of high-redshift (z ~ 2) dust obscured galaxies (DOGs). We identify 47 local DOGs with S 12 μm/S 0.22 μm >= 892 and S 12 μm > 20 mJy at 0.05 < z < 0.08 in the Sloan Digital Sky Survey data release 7. The infrared (IR) luminosities of these DOGs are in the range 3.4 × 1010 (L ⊙) <~ L IR <~ 7.0 × 1011 (L ⊙) with a median L IR of 2.1 × 1011 (L ⊙). We compare the physical properties of local DOGs with a control sample of galaxies that have lower S 12 μm/S 0.22 μm but have similar redshift, IR luminosity, and stellar mass distributions. Both WISE 12 μm and GALEX near-ultraviolet (NUV) flux densities of DOGs differ from the control sample of galaxies, but the difference is much larger in the NUV. Among the 47 DOGs, 36% ± 7% have small axis ratios in the optical (i.e., b/a < 0.6), larger than the fraction among the control sample (17% ± 3%). There is no obvious sign of interaction for many local DOGs. No local DOGs have companions with comparable optical magnitudes closer than ~50 kpc. The large- and small-scale environments of DOGs are similar to the control sample. Many physical properties of local DOGs are similar to those of high-z DOGs, even though the IR luminosities of local objects are an order of magnitude lower than for the high-z objects: the presence of two classes (active galactic nuclei- and star formation-dominated) of DOGs, abnormal faintness in the UV rather than extreme brightness in the mid-IR, and diverse optical morphology. These results suggest a common underlying physical origin of local and high-z DOGs. Both seem to represent the high-end tail of the dust obscuration distribution resulting from various physical mechanisms rather than a unique phase of galaxy evolution.

[Features of organization of nutrition for young athletes].

PubMed

Korosteleva, M M; Nikitiuk, D B; Volkova, L Iu

2013-01-01

Organization of nutrition for young athletes implied a regime, which includes the distribution of meals throughout the day, the multiplicity of power an nutrients that must be strictly consistent with the mode of the training process. Athletes' requirements in energy and nutrients vary considerably depending on the sport discipline and the amount of intense of physical activity. In the Institute of Nutrition of Russian Academy of Medical Sciences the recommended average daily sets of products, which are based on daily energy expenditure of young athletes, depending on the duration and intensity of physical activity in diverse kinds sports has been developed, these kits provide young athletes the necessary nutrients and micronutrients. In precompetitive period athletes must be given high physical activity and the diet should be mainly protein and fat-containing, with a high level of fiber. The training process should be intense for three days, then the athlete is advised to transfer to the carbohydrate-rich diet that is combined with a significant reduction in the intensity of trainings--glycogen super compensation. During competition period meal should be well digestible and low-volume. It must contain proteins of high biological values and carbohydrates in the required quantity. During this period the inclusion of new dishes and products in the menu for athletes is not desirable. During marathon the main aim is to recover the energy, water, mineral resources, and to maintain normal blood glucose concentrations. This is achieved in the following ways: carbohydrate intake with a relatively small amount of liquid, high product content of vitamins and minerals that helps to maintain the water-salt metabolism at the appropriate level, taking food in liquid form, in small portions. In the recovery period adequate nutrition should achieve the following objectives: to restore the acid-base and fluid and electrolyte balance, eliminate the effect of metabolic products (urea, lactic acid, ammonia, etc) associated with high physical activity; restore carbohydrate stores, provide plastic exchange, synthesis processes. The article also contains the basic sanitary and epidemiological requirements for the catering departments, selection of products and sports doctors.

Production of liquid fuels out of plant biomass and refuse: Methods, cost, potential (in MIXED)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woick, B.; Friedrich, R.

1981-09-01

Different ways of producing biomass and its conversion into high grade fuel for vehicles are reviewed with particular reference to physical and geographical factors, pertaining in the Federal Republic of Germany (FRG). Even with the potentially small amount of biomass in the FRG, the fueling of diesel engines with rape oil or modified ethanol, which can be obtained from any cellulosic feedstock, seems to pose the fewest difficulties and promises greatest efficiency. However, the amount of fuel produced from biomass can probably only meet a very small percentage of the total amount required.

Student Self-Efficacy in Introductory Project-Based Learning Courses

NASA Astrophysics Data System (ADS)

Pleiss, Geoffrey; Zastavker, Yevgeniya V.

2012-02-01

This study investigates first-year engineering students' self-efficacy in two introductory Project-Based Learning (PjBL) courses -- Physics (Mechanics) Laboratory and Engineering Design -- taught at a small technical institution. Twelve students participated in semi-structured open-ended interviews about their experiences in both courses. Analysis was performed using grounded theory. Results indicate that students had lower self-efficacy in Physics Lab than in Engineering Design. In Physics Lab, students reported high levels of faculty-supported scaffolding related to final project deliverables, which in turn established perceptions of an outcome-based course emphasis. Conversely, in Engineering Design, students observed high levels of scaffolding related to the intermediate project deliverables, highlighting process-centered aspects of the course. Our analyses indicate that this difference in student perceptions of course emphases -- resulting from the differences in scaffolding -- is a primary factor for the discrepancy in self-efficacy between Physics Lab and Engineering Design. Future work will examine how other variables (e.g., academic background, perception of community, gender) affect students' self-efficacy and perception of scaffolding in these PjBL courses.

International Physics Summer Camp for High School Students

NASA Astrophysics Data System (ADS)

Pope, Damian T.; Korsunsky, B.

2006-12-01

Each year for the past three years, Perimeter Institute for Theoretical Physics in Waterloo, Ontario, Canada, has staged an annual physics summer camp for high school students worldwide. Known as the International Summer School for Young Physicists (ISSYP), it attracts students from all corners of the globe and this year had attendees from 15 countries and 5 continents. The camp is aimed at motivated students around the age of 16 and is a two-week immersion into the exciting world of cutting-edge physics today. It covers topics such as dark matter, superstring theory and quantum computers, and exposes attendees to some of the very latest research results. It includes lectures, tutorials, laboratory visits and small-group projects and, in addition to teaching new material, strives to give students a deeper appreciation of the true nature of science. Throughout, attendees have a great deal of interaction with the institute's scientists. This presentation will give an overview of the camp including the material taught within it, its impact on students and the goals of the program. More information about the camp can be found at: http://www.youngphysicists.ca

The second evolution of ionic liquids: from solvents and separations to advanced materials--energetic examples from the ionic liquid cookbook.

PubMed

Smiglak, Marcin; Metlen, Andreas; Rogers, Robin D

2007-11-01

In this Account of the small portion of the recent research in ionic liquids (ILs) by the Rogers Group, we fast forward through the first evolution of IL research, where ILs were studied for their unique set of physical properties and the resulting potential for tunable "green solvents", to the second evolution of ILs, where the tunability of the cation and anion independently offers almost unlimited access to targeted combinations of physical and chemical properties. This approach is demonstrated here with the field of energetic ionic liquids (EILs), which utilizes this design flexibility to find safe synthetic routes to ILs with high energy content and targeted physical properties.

Search for the Footprints of New Physics with Laboratory and Cosmic Neutrinos

NASA Technical Reports Server (NTRS)

Stecker, Floyd W.

2017-01-01

Observations of high energy neutrinos, both in the laboratory and from cosmic sources, can be a useful probe in searching for new physics. Such observations can provide sensitive tests of Lorentz invariance violation (LIV), which may be a the result of quantum gravity physics (QG). We review some observationally testable consequences of LIV using effective field theory (EFT) formalism. To do this, one can postulate the existence of additional small LIV terms in free particle Lagrangians, suppressed by powers of the Planck mass. The observational consequences of such terms are then examined. In particular, one can place limits on a class of non-renormalizable, mass dimension five and six Lorentz invariance violating operators that may be the result of QG.

Understanding flavour at the LHC

ScienceCinema

Nir, Yosef

2018-05-22

Huge progress in flavour physics has been achieved by the two B-factories and the Tevatron experiments. This progress has, however, deepened the new physics flavour puzzle: If there is new physics at the TeV scale, why aren't flavour changing neutral current processes enhanced by orders of magnitude compared to the standard model predictions? The forthcoming ATLAS and CMS experiments can potentially solve this puzzle. Perhaps even more surprisingly, these experiments can potentially lead to progress in understanding the standard model flavour puzzle: Why is there smallness and hierarchy in the flavour parameters? Thus, a rich and informative flavour program is awaiting us not only in the flavour-dedicated LHCb experiment, but also in the high-pT ATLAS and CMS experiments.

Solid State Division progress report, September 30, 1981

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1982-04-01

Progress made during the 19 months from March 1, 1980, through September 30, 1981, is reported in the following areas: theoretical solid state physics (surfaces, electronic and magnetic properties, particle-solid interactions, and laser annealing); surface and near-surface properties of solids (plasma materials interactions, ion-solid interactions, pulsed laser annealing, and semiconductor physics and photovoltaic conversion); defects in solids (radiation effects, fracture, and defects and impurities in insulating crystals); transport properties of solids (fast-ion conductors, superconductivity, and physical properties of insulating materials); neutron scattering (small-angle scattering, lattice dynamics, and magnetic properties); crystal growth and characterization (nuclear waste forms, ferroelectric mateirals, high-temperature materials,more » and special materials); and isotope research materials. Publications and papers are listed. (WHK)« less

Quantum levitation of nanoparticles seen with ultracold neutrons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nesvizhevsky, V. V., E-mail: nesvizhevsky@ill.eu; Voronin, A. Yu.; Lambrecht, A.

2013-09-15

Analyzing new experiments with ultracold neutrons (UCNs) we show that physical adsorption of nanoparticles/nanodroplets, levitating in high-excited states in a deep and broad potential well formed by van der Waals/Casimir-Polder (vdW/CP) forces results in new effects on a cross-road of the fields of fundamental interactions, neutron, surface and nanoparticle physics. Accounting for the interaction of UCNs with nanoparticles explains a recently discovered intriguing so-called 'small heating' of UCNs in traps. It might be relevant to the striking conflict of the neutron lifetime experiments with smallest reported uncertainties by adding false effects there.

Welfare-to-work interventions and their effects on the mental and physical health of lone parents and their children.

PubMed

Gibson, Marcia; Thomson, Hilary; Banas, Kasia; Lutje, Vittoria; McKee, Martin J; Martin, Susan P; Fenton, Candida; Bambra, Clare; Bond, Lyndal

2018-02-26

Lone parents in high-income countries have high rates of poverty (including in-work poverty) and poor health. Employment requirements for these parents are increasingly common. 'Welfare-to-work' (WtW) interventions involving financial sanctions and incentives, training, childcare subsidies and lifetime limits on benefit receipt have been used to support or mandate employment among lone parents. These and other interventions that affect employment and income may also affect people's health, and it is important to understand the available evidence on these effects in lone parents. To assess the effects of WtW interventions on mental and physical health in lone parents and their children living in high-income countries. The secondary objective is to assess the effects of welfare-to-work interventions on employment and income. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE Ovid, Embase Ovid, PsycINFO EBSCO, ERIC EBSCO, SocINDEX EBSCO, CINAHL EBSCO, Econlit EBSCO, Web of Science ISI, Applied Social Sciences Index and Abstracts (ASSIA) via Proquest, International Bibliography of the Social Sciences (IBSS) via ProQuest, Social Services Abstracts via Proquest, Sociological Abstracts via Proquest, Campbell Library, NHS Economic Evaluation Database (NHS EED) (CRD York), Turning Research into Practice (TRIP), OpenGrey and Planex. We also searched bibliographies of included publications and relevant reviews, in addition to many relevant websites. We identified many included publications by handsearching. We performed the searches in 2011, 2013 and April 2016. Randomised controlled trials (RCTs) of mandatory or voluntary WtW interventions for lone parents in high-income countries, reporting impacts on parental mental health, parental physical health, child mental health or child physical health. One review author extracted data using a standardised extraction form, and another checked them. Two authors independently assessed risk of bias and the quality of the evidence. We contacted study authors to obtain measures of variance and conducted meta-analyses where possible. We synthesised data at three time points: 18 to 24 months (T1), 25 to 48 months (T2) and 49 to 72 months (T3). Twelve studies involving 27,482 participants met the inclusion criteria. Interventions were either mandatory or voluntary and included up to 10 discrete components in varying combinations. All but one study took place in North America. Although we searched for parental health outcomes, the vast majority of the sample in all included studies were female. Therefore, we describe adult health outcomes as 'maternal' throughout the results section. We downgraded the quality of all evidence at least one level because outcome assessors were not blinded. Follow-up ranged from 18 months to six years. The effects of welfare-to-work interventions on health were generally positive but of a magnitude unlikely to have any tangible effects.At T1 there was moderate-quality evidence of a very small negative impact on maternal mental health (standardised mean difference (SMD) 0.07, 95% Confidence Interval (CI) 0.00 to 0.14; N = 3352; studies = 2)); at T2, moderate-quality evidence of no effect (SMD 0.00, 95% CI 0.05 to 0.05; N = 7091; studies = 3); and at T3, low-quality evidence of a very small positive effect (SMD -0.07, 95% CI -0.15 to 0.00; N = 8873; studies = 4). There was evidence of very small positive effects on maternal physical health at T1 (risk ratio (RR) 0.85, 95% CI 0.54 to 1.36; N = 311; 1 study, low quality) and T2 (RR 1.06, 95% CI 0.95 to 1.18; N = 2551; 2 studies, moderate quality), and of a very small negative effect at T3 (RR 0.97, 95% CI 0.91 to 1.04; N = 1854; 1 study, low quality).At T1, there was moderate-quality evidence of a very small negative impact on child mental health (SMD 0.01, 95% CI -0.06 to 0.09; N = 2762; studies = 1); at T2, of a very small positive effect (SMD -0.04, 95% CI -0.08 to 0.01; N = 7560; studies = 5), and at T3, there was low-quality evidence of a very small positive effect (SMD -0.05, 95% CI -0.16 to 0.05; N = 3643; studies = 3). Moderate-quality evidence for effects on child physical health showed a very small negative effect at T1 (SMD -0.05, 95% CI -0.12 to 0.03; N = 2762; studies = 1), a very small positive effect at T2 (SMD 0.07, 95% CI 0.01 to 0.12; N = 7195; studies = 3), and a very small positive effect at T3 (SMD 0.01, 95% CI -0.04 to 0.06; N = 8083; studies = 5). There was some evidence of larger negative effects on health, but this was of low or very low quality.There were small positive effects on employment and income at 18 to 48 months (moderate-quality evidence), but these were largely absent at 49 to 72 months (very low to moderate-quality evidence), often due to control group members moving into work independently. Since the majority of the studies were conducted in North America before the year 2000, generalisabilty may be limited. However, all study sites were similar in that they were high-income countries with developed social welfare systems. The effects of WtW on health are largely of a magnitude that is unlikely to have tangible impacts. Since income and employment are hypothesised to mediate effects on health, it is possible that these negligible health impacts result from the small effects on economic outcomes. Even where employment and income were higher for the lone parents in WtW, poverty was still high for the majority of the lone parents in many of the studies. Perhaps because of this, depression also remained very high for lone parents whether they were in WtW or not. There is a lack of robust evidence on the health effects of WtW for lone parents outside North America.

Welfare-to-work interventions and their effects on the mental and physical health of lone parents and their children.

PubMed

Gibson, Marcia; Thomson, Hilary; Banas, Kasia; Lutje, Vittoria; McKee, Martin J; Martin, Susan P; Fenton, Candida; Bambra, Clare; Bond, Lyndal

2017-08-20

Lone parents in high-income countries have high rates of poverty (including in-work poverty) and poor health. Employment requirements for these parents are increasingly common. 'Welfare-to-work' (WtW) interventions involving financial sanctions and incentives, training, childcare subsidies and lifetime limits on benefit receipt have been used to support or mandate employment among lone parents. These and other interventions that affect employment and income may also affect people's health, and it is important to understand the available evidence on these effects in lone parents. To assess the effects of WtW interventions on mental and physical health in lone parents and their children living in high-income countries. The secondary objective is to assess the effects of welfare-to-work interventions on employment and income. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE Ovid, Embase Ovid, PsycINFO EBSCO, ERIC EBSCO, SocINDEX EBSCO, CINAHL EBSCO, Econlit EBSCO, Web of Science ISI, Applied Social Sciences Index and Abstracts (ASSIA) via Proquest, International Bibliography of the Social Sciences (IBSS) via ProQuest, Social Services Abstracts via Proquest, Sociological Abstracts via Proquest, Campbell Library, NHS Economic Evaluation Database (NHS EED) (CRD York), Turning Research into Practice (TRIP), OpenGrey and Planex. We also searched bibliographies of included publications and relevant reviews, in addition to many relevant websites. We identified many included publications by handsearching. We performed the searches in 2011, 2013 and April 2016. Randomised controlled trials (RCTs) of mandatory or voluntary WtW interventions for lone parents in high-income countries, reporting impacts on parental mental health, parental physical health, child mental health or child physical health. One review author extracted data using a standardised extraction form, and another checked them. Two authors independently assessed risk of bias and the quality of the evidence. We contacted study authors to obtain measures of variance and conducted meta-analyses where possible. We synthesised data at three time points: 18 to 24 months (T1), 25 to 48 months (T2) and 49 to 72 months (T3). Twelve studies involving 27,482 participants met the inclusion criteria. Interventions were either mandatory or voluntary and included up to 10 discrete components in varying combinations. All but one study took place in North America. Although we searched for parental health outcomes, the vast majority of the sample in all included studies were female. Therefore, we describe adult health outcomes as 'maternal' throughout the results section. We downgraded the quality of all evidence at least one level because outcome assessors were not blinded. Follow-up ranged from 18 months to six years. The effects of welfare-to-work interventions on health were generally positive but of a magnitude unlikely to have any tangible effects.At T1 there was moderate-quality evidence of a very small negative impact on maternal mental health (standardised mean difference (SMD) 0.07, 95% Confidence Interval (CI) 0.00 to 0.14; N = 3352; studies = 2)); at T2, moderate-quality evidence of no effect (SMD 0.00, 95% CI 0.05 to 0.05; N = 7091; studies = 3); and at T3, low-quality evidence of a very small positive effect (SMD -0.07, 95% CI -0.15 to 0.00; N = 8873; studies = 4). There was evidence of very small positive effects on maternal physical health at T1 (risk ratio (RR) 0.85, 95% CI 0.54 to 1.36; N = 311; 1 study, low quality) and T2 (RR 1.06, 95% CI 0.95 to 1.18; N = 2551; 2 studies, moderate quality), and of a very small negative effect at T3 (RR 0.97, 95% CI 0.91 to 1.04; N = 1854; 1 study, low quality).At T1, there was moderate-quality evidence of a very small negative impact on child mental health (SMD 0.01, 95% CI -0.06 to 0.09; N = 2762; studies = 1); at T2, of a very small positive effect (SMD -0.04, 95% CI -0.08 to 0.01; N = 7560; studies = 5), and at T3, there was low-quality evidence of a very small positive effect (SMD -0.05, 95% CI -0.16 to 0.05; N = 3643; studies = 3). Moderate-quality evidence for effects on child physical health showed a very small negative effect at T1 (SMD -0.05, 95% CI -0.12 to 0.03; N = 2762; studies = 1), a very small positive effect at T2 (SMD 0.07, 95% CI 0.01 to 0.12; N = 7195; studies = 3), and a very small positive effect at T3 (SMD 0.01, 95% CI -0.04 to 0.06; N = 8083; studies = 5). There was some evidence of larger negative effects on health, but this was of low or very low quality.There were small positive effects on employment and income at 18 to 48 months (moderate-quality evidence), but these were largely absent at 49 to 72 months (very low to moderate-quality evidence), often due to control group members moving into work independently. Since the majority of the studies were conducted in North America before the year 2000, generalisabilty may be limited. However, all study sites were similar in that they were high-income countries with developed social welfare systems. The effects of WtW on health are largely of a magnitude that is unlikely to have tangible impacts. Since income and employment are hypothesised to mediate effects on health, it is possible that these negligible health impacts result from the small effects on economic outcomes. Even where employment and income were higher for the lone parents in WtW, poverty was still high for the majority of the lone parents in many of the studies. Perhaps because of this, depression also remained very high for lone parents whether they were in WtW or not. There is a lack of robust evidence on the health effects of WtW for lone parents outside North America.

Contributing to Meaning Making: Facilitating Discourse in the High School Physics Classroom

NASA Astrophysics Data System (ADS)

Hovan, Scot Alan

The Next Generation Science Standards (NGSS) identify eight practices as essential to science and engineering, and these practices include asking students to construct explanations, to engage in argumentation, and to communicate scientific information. However, few teacher-training programs instruct teachers how to facilitate such discourse in the classroom. Modeling Instruction is one movement in physics education that organizes high school physics content around a small number of student-derived scientific models, and it relies on student discourse for the design, development, and deployment of these models. This research is a self-study of one high school physics teacher's experience facilitating large group discourse in the high school modeling physics classroom. Whiteboard meetings and graded discussions were examined by applying the analytical framework created by Mortimer and Scott (2003) to characterize the classroom talk and the discourse facilitation moves that I employed. In addition, elements of discourse analysis were used to examine some of the tensions that I experienced in the facilitation of this discourse. The findings suggest that deliberate identification of the teaching purposes for the discussion can help determine the scaffolding needed for students to enter the Discourse (Gee, 2011) of being a participant in these large group conversations. In addition, connecting the dialogic dimension of exploring student ideas with the authoritative dimension of introducing the scientific view and supporting the internalization of that view is necessary to contribute to meaning making in the science classroom.

Preliminary results for the design, fabrication, and performance of a backside-illuminated avalanche drift detector

NASA Astrophysics Data System (ADS)

Qiao, Yun; Liang, Kun; Chen, Wen-Fei; Han, De-Jun

2013-10-01

The detection of low-level light is a key technology in various experimental scientific studies. As a photon detector, the silicon photomultiplier (SiPM) has gradually become an alternative to the photomultiplier tube (PMT) in many applications in high-energy physics, astroparticle physics, and medical imaging because of its high photon detection efficiency (PDE), good resolution for single-photon detection, insensitivity to magnetic field, low operating voltage, compactness, and low cost. However, primarily because of the geometric fill factor, the PDE of most SiPMs is not very high; in particular, for those SiPMs with a high density of micro cells, the effective area is small, and the bandwidth of the light response is narrow. As a building block of the SiPM, the concept of the backside-illuminated avalanche drift detector (ADD) was first proposed by the Max Planck Institute of Germany eight years ago; the ADD is promising to have high PDE over the full energy range of optical photons, even ultraviolet light and X-ray light, and because the avalanche multiplication region is very small, the ADD is beneficial for the fabrication of large-area SiPMs. However, because of difficulties in design and fabrication, no significant progress had been made, and the concept had not yet been verified. In this paper, preliminary results in the design, fabrication, and performance of a backside-illuminated ADD are reported; the difficulties in and limitations to the backside-illuminated ADD are analyzed.

Physical fitness in children with high motor competence is different from that in children with low motor competence.

PubMed

Haga, Monika

2009-10-01

Physical therapists often treat children with low motor competence. Earlier studies have demonstrated poor physical fitness outcomes and a reduced level of physical activity for these children compared with their peers with normal motor skills. The aim of this study was to examine how physical fitness developed over time in 2 groups of children: those with a low level of competence in motor skills (low motor competence [LMC]), and those with a high level of competence in motor skills (high motor competence [HMC]). From an initial sample of 67 children, a group of 18 was identified as having HMC or LMC on the Movement Assessment Battery for Children and was selected for the present study. Eight children (3 girls and 5 boys) comprised the LMC group, and 10 children (4 girls and 6 boys) made up the HMC group. A longitudinal design was implemented, and physical fitness in the 2 groups was evaluated by measuring different fitness components over a period of 32 months. A mixed-effects analysis of variance revealed significant main effects for group and for time but no group x time interaction effect. The LMC group performed less well on all physical fitness measures than the HMC group, and both groups scored significantly higher on the physical fitness test after a period of 32 months. The lack of a significant interaction effect indicated that the relative differences in physical fitness outcomes between the groups were relatively constant over time. This study was limited by the small sample size and lack of assessment of anthropometric variables and children's perceived self-efficacy. Children with LMC are likely to have poor physical fitness compared with children with HMC. The differences in physical fitness outcomes between the groups were relatively constant over time. Given that various physical fitness components are linked to different health outcomes, these consequences are matters of concern for both current health status and later health status in children with LMC.

Effects of different doses of high-speed resistance training on physical performance and quality of life in older women: a randomized controlled trial

PubMed Central

Ramirez-Campillo, Rodrigo; Diaz, Daniela; Martinez-Salazar, Cristian; Valdés-Badilla, Pablo; Delgado-Floody, Pedro; Méndez-Rebolledo, Guillermo; Cañas-Jamet, Rodrigo; Cristi-Montero, Carlos; García-Hermoso, Antonio; Celis-Morales, Carlos; Moran, Jason; Buford, Thomas W; Rodriguez-Mañas, Leocadio; Alonso-Martinez, Alicia M; Izquierdo, Mikel

2016-01-01

Objective This study aimed to compare the effects of two frequencies of high-speed resistance training (HSRT) on physical performance and quality of life of older women. Methods A total of 24 older women participated in a 12-week HSRT program composed of either two or three sessions/week (equated for volume and intensity). Women were randomized into three arms: a control group (CG, n=8), a resistance training group performing two sessions/week (RT2, n=8), and a resistance training group performing three sessions/week (RT3, n=8). The training program for both experimental groups included exercises that required high-speed concentric muscle actions. Results No baseline differences were observed among groups. Compared with the CG, both training groups showed similar small to moderate improvements (P<0.05) in muscle strength, power, functional performance, balance, and quality of life. Conclusion These results suggest that equated for volume and intensity, two and three training sessions/week of HSRT are equally effective for improving physical performance and quality of life of older women. PMID:28008239

Fast Readout Architectures for Large Arrays of Digital Pixels: Examples and Applications

PubMed Central

Gabrielli, A.

2014-01-01

Modern pixel detectors, particularly those designed and constructed for applications and experiments for high-energy physics, are commonly built implementing general readout architectures, not specifically optimized in terms of speed. High-energy physics experiments use bidimensional matrices of sensitive elements located on a silicon die. Sensors are read out via other integrated circuits bump bonded over the sensor dies. The speed of the readout electronics can significantly increase the overall performance of the system, and so here novel forms of readout architectures are studied and described. These circuits have been investigated in terms of speed and are particularly suited for large monolithic, low-pitch pixel detectors. The idea is to have a small simple structure that may be expanded to fit large matrices without affecting the layout complexity of the chip, while maintaining a reasonably high readout speed. The solutions might be applied to devices for applications not only in physics but also to general-purpose pixel detectors whenever online fast data sparsification is required. The paper presents also simulations on the efficiencies of the systems as proof of concept for the proposed ideas. PMID:24778588

Effects of different doses of high-speed resistance training on physical performance and quality of life in older women: a randomized controlled trial.

PubMed

Ramirez-Campillo, Rodrigo; Diaz, Daniela; Martinez-Salazar, Cristian; Valdés-Badilla, Pablo; Delgado-Floody, Pedro; Méndez-Rebolledo, Guillermo; Cañas-Jamet, Rodrigo; Cristi-Montero, Carlos; García-Hermoso, Antonio; Celis-Morales, Carlos; Moran, Jason; Buford, Thomas W; Rodriguez-Mañas, Leocadio; Alonso-Martinez, Alicia M; Izquierdo, Mikel

2016-01-01

This study aimed to compare the effects of two frequencies of high-speed resistance training (HSRT) on physical performance and quality of life of older women. A total of 24 older women participated in a 12-week HSRT program composed of either two or three sessions/week (equated for volume and intensity). Women were randomized into three arms: a control group (CG, n=8), a resistance training group performing two sessions/week (RT2, n=8), and a resistance training group performing three sessions/week (RT3, n=8). The training program for both experimental groups included exercises that required high-speed concentric muscle actions. No baseline differences were observed among groups. Compared with the CG, both training groups showed similar small to moderate improvements ( P <0.05) in muscle strength, power, functional performance, balance, and quality of life. These results suggest that equated for volume and intensity, two and three training sessions/week of HSRT are equally effective for improving physical performance and quality of life of older women.

Impacts of spectral nudging on the simulated surface air temperature in summer compared with the selection of shortwave radiation and land surface model physics parameterization in a high-resolution regional atmospheric model

NASA Astrophysics Data System (ADS)

Park, Jun; Hwang, Seung-On

2017-11-01

The impact of a spectral nudging technique for the dynamical downscaling of the summer surface air temperature in a high-resolution regional atmospheric model is assessed. The performance of this technique is measured by comparing 16 analysis-driven simulation sets of physical parameterization combinations of two shortwave radiation and four land surface model schemes of the model, which are known to be crucial for the simulation of the surface air temperature. It is found that the application of spectral nudging to the outermost domain has a greater impact on the regional climate than any combination of shortwave radiation and land surface model physics schemes. The optimal choice of two model physics parameterizations is helpful for obtaining more realistic spatiotemporal distributions of land surface variables such as the surface air temperature, precipitation, and surface fluxes. However, employing spectral nudging adds more value to the results; the improvement is greater than using sophisticated shortwave radiation and land surface model physical parameterizations. This result indicates that spectral nudging applied to the outermost domain provides a more accurate lateral boundary condition to the innermost domain when forced by analysis data by securing the consistency with large-scale forcing over a regional domain. This consequently indirectly helps two physical parameterizations to produce small-scale features closer to the observed values, leading to a better representation of the surface air temperature in a high-resolution downscaled climate.

Recent advances in electron tomography: TEM and HAADF-STEM tomography for materials science and semiconductor applications.

PubMed

Kübel, Christian; Voigt, Andreas; Schoenmakers, Remco; Otten, Max; Su, David; Lee, Tan-Chen; Carlsson, Anna; Bradley, John

2005-10-01

Electron tomography is a well-established technique for three-dimensional structure determination of (almost) amorphous specimens in life sciences applications. With the recent advances in nanotechnology and the semiconductor industry, there is also an increasing need for high-resolution three-dimensional (3D) structural information in physical sciences. In this article, we evaluate the capabilities and limitations of transmission electron microscopy (TEM) and high-angle-annular-dark-field scanning transmission electron microscopy (HAADF-STEM) tomography for the 3D structural characterization of partially crystalline to highly crystalline materials. Our analysis of catalysts, a hydrogen storage material, and different semiconductor devices shows that features with a diameter as small as 1-2 nm can be resolved in three dimensions by electron tomography. For partially crystalline materials with small single crystalline domains, bright-field TEM tomography provides reliable 3D structural information. HAADF-STEM tomography is more versatile and can also be used for high-resolution 3D imaging of highly crystalline materials such as semiconductor devices.

Exploring the impact of high intensity interval training on adolescents' objectively measured physical activity: Findings from a randomized controlled trial.

PubMed

Costigan, Sarah A; Ridgers, Nicola D; Eather, Narelle; Plotnikoff, Ronald C; Harris, Nigel; Lubans, David R

2018-05-01

High Intensity Interval Training (HIIT) may be effective for accumulating VPA. However, the contribution of HIIT to overall physical activity is unknown. Our primary aim was to explore the impact of school-based HIIT on physical activity. The secondary aim was to explore within-individual changes in physical activity after participating in HIIT. Participants [n = 65; 15.8(0.6)years] were randomized to a HIIT or control group. Intervention groups participated in three HIIT sessions/week. GENEActiv accelerometers assessed objective physical activity at baseline and week-one, to detect changes in MPA and VPA. Intervention effects were examined using linear mixed models and evidence of a change in physical activity (i.e., compensation) were examined using multilevel linear regression models. The group-by-time interaction effects for MPA and VPA were small and moderate, respectively. Adjusted difference between groups for VPA was 1.70 min/day, 95%CI -1.96 to 5.36; p = 0.354; d = 0.55). Embedding HIIT within the school-day had a moderate effect on VPA compared to controls. Compensation analyses (i.e., individual level) suggested that adolescents were more active on days when they participated in HIIT. Further studies are needed to test the effects of HIIT on adolescents' physical activity over extended time periods.

Comparison of technical and physical activities between 8 vs. 8 and 11 vs. 11 games in young Korean soccer players.

PubMed

Oh, Seong Hwan; Joo, Chang Hwa

2018-04-01

The aims of this study were to examine the differences in technical aspects and physical demands between small-size games (SSG; 8 vs. 8) and regular-size games (RSG; 11 vs. 11) in young Korean soccer players. Seventy-nine young soccer players from 6 teams (U-12) volunteered to participate in the study. The players completed 4 games (2 SSG, 62×51 m, and 2 RSG, 80×54 m) in 2 days. Each game was filmed to evaluate technical actions. Physical demand variables were measured using global positioning system technology. SSG showed significantly greater numbers of technical plays among 17 variables when compared to RSG ( P <0.05). The players covered significantly greater total distance during low-, moderate-, and high-speed running and sprinting in SSG than in RSG ( P <0.05). Higher numbers of high-intensity activities (repeated high-intensity efforts, explosive efforts, decelera-tions, accelerations, and sprinting) were observed in SSG compared to RSG ( P <0.05). Mean heart rate was also higher in SSG than in RSG ( P <0.05). Despite the greater physical demands during SSG, the exercise intensity was similar to that reported in previous studies. Therefore, the SSG format applied in the present study can be a suitable official game format for Korean young soccer players, resulting in significantly greater exposure to technical plays without excessive physical demands.

Physiotherapists use a small number of behaviour change techniques when promoting physical activity: A systematic review comparing experimental and observational studies.

PubMed

Kunstler, Breanne E; Cook, Jill L; Freene, Nicole; Finch, Caroline F; Kemp, Joanne L; O'Halloran, Paul D; Gaida, James E

2018-06-01

Physiotherapists promote physical activity as part of their practice. This study reviewed the behaviour change techniques physiotherapists use when promoting physical activity in experimental and observational studies. Systematic review of experimental and observational studies. Twelve databases were searched using terms related to physiotherapy and physical activity. We included experimental studies evaluating the efficacy of physiotherapist-led physical activity interventions delivered to adults in clinic-based private practice and outpatient settings to individuals with, or at risk of, non-communicable diseases. Observational studies reporting the techniques physiotherapists use when promoting physical activity were also included. The behaviour change techniques used in all studies were identified using the Behaviour Change Technique Taxonomy. The behaviour change techniques appearing in efficacious and inefficacious experimental interventions were compared using a narrative approach. Twelve studies (nine experimental and three observational) were retained from the initial search yield of 4141. Risk of bias ranged from low to high. Physiotherapists used seven behaviour change techniques in the observational studies, compared to 30 behaviour change techniques in the experimental studies. Social support (unspecified) was the most frequently identified behaviour change technique across both settings. Efficacious experimental interventions used more behaviour change techniques (n=29) and functioned in more ways (n=6) than did inefficacious experimental interventions (behaviour change techniques=10 and functions=1). Physiotherapists use a small number of behaviour change techniques. Less behaviour change techniques were identified in observational studies compared to experimental studies, suggesting physiotherapists use less BCTs clinically than experimentally. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Interaction between numbers and size during visual search.

PubMed

Krause, Florian; Bekkering, Harold; Pratt, Jay; Lindemann, Oliver

2017-05-01

The current study investigates an interaction between numbers and physical size (i.e. size congruity) in visual search. In three experiments, participants had to detect a physically large (or small) target item among physically small (or large) distractors in a search task comprising single-digit numbers. The relative numerical size of the digits was varied, such that the target item was either among the numerically large or small numbers in the search display and the relation between numerical and physical size was either congruent or incongruent. Perceptual differences of the stimuli were controlled by a condition in which participants had to search for a differently coloured target item with the same physical size and by the usage of LCD-style numbers that were matched in visual similarity by shape transformations. The results of all three experiments consistently revealed that detecting a physically large target item is significantly faster when the numerical size of the target item is large as well (congruent), compared to when it is small (incongruent). This novel finding of a size congruity effect in visual search demonstrates an interaction between numerical and physical size in an experimental setting beyond typically used binary comparison tasks, and provides important new evidence for the notion of shared cognitive codes for numbers and sensorimotor magnitudes. Theoretical consequences for recent models on attention, magnitude representation and their interactions are discussed.

KSC-01pp1075

NASA Image and Video Library

2001-06-05

KENNEDY SPACE CENTER, Fla. -- The High Energy Solar Spectroscopic Imager (HESSI) spacecraft, which will be launched by a Pegasus XL rocket, arrives at the Skid Strip at Cape Canaveral Air Force Station. Part of NASA's Small Explorer Program, HESSI's primary mission is to explore the basic physics of particle acceleration and explosive energy release in solar flares. Launch is scheduled for no earlier than June 14

[The bodies of dwarfs in Italian art during the Renaissance].

PubMed

Portmann, Maria

2014-01-01

Agnolo Bronzino's painting of Nano Morgante depicts for the first time the anatomy of a dwarf. This image testifies Cosimo's special interest for this dwarf. In Antonio Francesco Grazzini's poem written in Nano Morgante's honor, we underline some interesting aspects of his physical deformities and his small height, which are highly praised as we can see them on the painting.

Millikan's Oil-Drop Experiment: A Centennial Setup Revisited in Virtual World

NASA Astrophysics Data System (ADS)

Gagnon, Michel

2012-02-01

Early in the last century, Robert Millikan developed a precise method of determining the electric charge carried by oil droplets.1-3 Using a microscope and a small incandescent lamp, he observed the fall of charged droplets under the influence of an electric field inside a small observation chamber. In so doing, Millikan demonstrated the existence of a fundamental unit of electric charge, and established its quantization. Now renowned as one of the most famous experiments of 20th-century physics, Millikan's oil-drop experiment has been reproduced with more or less success in most, if not all, high school and university physics classes. This has encouraged many improvements of the apparatus, now making this experiment much more accurate and easier to realize for advanced students. However, the required apparatus remains rather expensive, and for introductory college or high school students the experiment is still quite difficult to conduct. As an alternative to the traditional setup, a realistic computer-based simulator to replicate the Millikan oil-drop experiment has been developed. Using this software, students are able to undertake a complete experiment, obtain an accurate set of results, and thus gain a better understanding of the original experiment and its historical importance.

Physics Education Research efforts to promote diversity: Challenges and opportunities

NASA Astrophysics Data System (ADS)

Brahmia, Suzanne

2015-04-01

We begin this talk with a brief description of the gender and ethnic diversity of the physics community. We then discuss several current efforts within Physics Education Research that have the potential to further our understanding of issues surrounding underrepresentation. These efforts include research into (1) the role of community and strategies for developing effective communities; (2) physics identity and self-efficacy; (3) the affordances that students from underrepresented groups bring to physics learning; (4) socioeconomics and its impact on mathematization. One of the challenges to conducting this research is the relatively small proportion of underrepresented minority students in current physics classes, and the small number of women in physics and engineering majors. In collaboration with Stephen Kanim, New Mexico State University.

Health-related quality of life among adults 65 years and older in the United States, 2011-2012: a multilevel small area estimation approach.

PubMed

Lin, Yu-Hsiu; McLain, Alexander C; Probst, Janice C; Bennett, Kevin J; Qureshi, Zaina P; Eberth, Jan M

2017-01-01

The purpose of this study was to develop county-level estimates of poor health-related quality of life (HRQOL) among aged 65 years and older U.S. adults and to identify spatial clusters of poor HRQOL using a multilevel, poststratification approach. Multilevel, random-intercept models were fit to HRQOL data (two domains: physical health and mental health) from the 2011-2012 Behavioral Risk Factor Surveillance System. Using a poststratification, small area estimation approach, we generated county-level probabilities of having poor HRQOL for each domain in U.S. adults aged 65 and older, and validated our model-based estimates against state and county direct estimates. County-level estimates of poor HRQOL in the United States ranged from 18.07% to 44.81% for physical health and 14.77% to 37.86% for mental health. Correlations between model-based and direct estimates were higher for physical than mental HRQOL. Counties located in the Arkansas, Kentucky, and Mississippi exhibited the worst physical HRQOL scores, but this pattern did not hold for mental HRQOL, which had the highest probability of mentally unhealthy days in Illinois, Indiana, and Vermont. Substantial geographic variation in physical and mental HRQOL scores exists among older U.S. adults. State and local policy makers should consider these local conditions in targeting interventions and policies to counties with high levels of poor HRQOL scores. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of Small-Sided Games vs. Interval Training in Aerobic Fitness and Physical Enjoyment in Young Elite Soccer Players

PubMed Central

Martín, Juan; Lerga, Javier; Sánchez, Felipe; Villagra, Federico; Zulueta, Javier J.

2015-01-01

The purpose of this study was to compare the effects of Small-Sided Games (SSG) vs. Interval Training (IT) in soccer training on aerobic fitness and physical enjoyment in youth elite soccer players during the last 8 weeks of the season. Seventeen U-16 male soccer players (age = 15.5 ± 0.6 years, and 8.5 years of experience) of a Spanish First Division club academy were randomized to 2 different groups for 6 weeks: SSG group (n = 9) and IT group (n = 8). In addition to the usual technical and tactical sessions and competitive games, the SSG group performed 11 sessions with different SSGs, whereas the IT group performed the same number of sessions of IT. Players were tested before and after the 6-week training intervention with a continuous maximal multistage running field test and the counter movement jump test (CMJ). At the end of the study, players answered the physical activity enjoyment scale (PACES). During the study, heart rate (HR) and session perceived effort (sRPE) were assessed. SSGs were as effective as IT in maintaining the aerobic fitness in elite young soccer players during the last weeks of the season. Players in the SSG group declared a greater physical enjoyment than IT (P = 0.006; ES = 1.86 ± 1.07). Coaches could use SSG training during the last weeks of the season as an option without fear of losing aerobic fitness while promoting high physical enjoyment. PMID:26331623

Small effort, high impact: Focus on physical activity improves oxygen uptake (VO2peak ), quality of life, and mental health after pediatric renal transplantation.

PubMed

Thorsteinsdottir, Hjørdis; Diseth, Trond H; Lie, Anine; Tangeraas, Trine; Matthews, Iren; Åsberg, Anders; Bjerre, Anna

2018-06-19

This study estimates the effects on peak oxygen uptake (VO 2 peak ), QoL, and mental health after the introduction of an adjusted post-transplant follow-up program, that is, early physiotherapy and focus on the importance of physical activity. VO 2 peak was measured by a treadmill exercise test in 20 renal-transplanted children on the adjusted post-transplant follow-up and compared with a group of 22 patients investigated in a previously, before the implementation of our new follow-up routines. PedsQL and The Strengths and Difficulties Questionnaire (SDQ) were used to assess QoL and mental health in 45 patients on the new as compared to 32 patients on the previous follow-up strategy. The patients exposed to early physiotherapy and a higher focus on physical activity had significantly higher VO 2 peak (44.3 vs 33.5 mL kg -1  min -1 , P = .031) in addition to improved QoL (P = .003) and mental health scores (P = .012). The cardiovascular risk profile was similar in both groups aside from significantly higher triglycerides in the present cohort. Small efforts as early physiotherapy and increased focus on physical activity after pediatric renal transplantation have significant impact on cardiorespiratory fitness, QoL, and mental health. The importance of physical activity should therefore be emphasized in follow-up programs. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The Physics Force presents The Physics Circus

NASA Astrophysics Data System (ADS)

Dahlberg, E. Dan

2015-03-01

The Physics Force of the University of Minnesota is an outreach program developed with the goal to show students and the public Science is Fun, Science is Interesting, and Science is Understandable. The program grew from a rather small effort by three high school physics teachers and two University of Minnesota staff members. In the almost three decades since its humble beginnings of 100 attendees in a year, it has grown to an average attendance of over 36,000 annually. In the last three years alone, about 110,000 Minnesotans have seen a performance of The Physics Circus which is roughly 2% of the population of the state. In addition to the performances in Minnesota, The Force performed two years at Disney's Epcot Center, was featured on Newton's Apple, and made appearances on the very successful German TV science show, the Knoff-Hoff Show. I will begin the talk with some of our motivation to develop The Physics Force arising from the current ``scientific state'' of our society and then provide more information on The Force including both some history and examples taken from our Physics Circus.

Synchronization of random bit generators based on coupled chaotic lasers and application to cryptography.

PubMed

Kanter, Ido; Butkovski, Maria; Peleg, Yitzhak; Zigzag, Meital; Aviad, Yaara; Reidler, Igor; Rosenbluh, Michael; Kinzel, Wolfgang

2010-08-16

Random bit generators (RBGs) constitute an important tool in cryptography, stochastic simulations and secure communications. The later in particular has some difficult requirements: high generation rate of unpredictable bit strings and secure key-exchange protocols over public channels. Deterministic algorithms generate pseudo-random number sequences at high rates, however, their unpredictability is limited by the very nature of their deterministic origin. Recently, physical RBGs based on chaotic semiconductor lasers were shown to exceed Gbit/s rates. Whether secure synchronization of two high rate physical RBGs is possible remains an open question. Here we propose a method, whereby two fast RBGs based on mutually coupled chaotic lasers, are synchronized. Using information theoretic analysis we demonstrate security against a powerful computational eavesdropper, capable of noiseless amplification, where all parameters are publicly known. The method is also extended to secure synchronization of a small network of three RBGs.

Computational Aerodynamic Modeling of Small Quadcopter Vehicles

NASA Technical Reports Server (NTRS)

Yoon, Seokkwan; Ventura Diaz, Patricia; Boyd, D. Douglas; Chan, William M.; Theodore, Colin R.

2017-01-01

High-fidelity computational simulations have been performed which focus on rotor-fuselage and rotor-rotor aerodynamic interactions of small quad-rotor vehicle systems. The three-dimensional unsteady Navier-Stokes equations are solved on overset grids using high-order accurate schemes, dual-time stepping, low Mach number preconditioning, and hybrid turbulence modeling. Computational results for isolated rotors are shown to compare well with available experimental data. Computational results in hover reveal the differences between a conventional configuration where the rotors are mounted above the fuselage and an unconventional configuration where the rotors are mounted below the fuselage. Complex flow physics in forward flight is investigated. The goal of this work is to demonstrate that understanding of interactional aerodynamics can be an important factor in design decisions regarding rotor and fuselage placement for next-generation multi-rotor drones.

Physical picture of immersed diode experiments on HERMES III and SABRE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olson, C.L.; Mazarakis, M.G.; Menge, P.R.

A needle-like, high-current, electron beam has been produced on the Hermes III and SABRE accelerators at SNL using inductive voltage adder (IVA) technology, and a diode consisting of a needle cathode and a planar anode/bremmstrahlung converter which are both fully immersed in a strong solenoidal magnetic field (12--50 T). Desired nominal parameters are 10 MV, 40 kA, 0.5 mm radius cathode, and 5--35 cm anode-cathode gaps. High dose and small x-ray spot size are required for radiography applications. Results are presented of initial experiments on Hermes III and SABRE, which have produced doses up to 1 kRad {at} 1 meter,more » and at lower doses, spot sizes as small as 1.7 mm diameter.« less

Force-velocity relation for actin-polymerization-driven motility from Brownian dynamics simulations.

PubMed

Lee, Kun-Chun; Liu, Andrea J

2009-09-02

We report numerical simulation results for the force-velocity relation for actin-polymerization-driven motility. We use Brownian dynamics to solve a physically consistent formulation of the dendritic nucleation model with semiflexible filaments that self-assemble and push a disk. We find that at small loads, the disk speed is independent of load, whereas at high loads, the speed decreases and vanishes at a characteristic stall pressure. Our results demonstrate that at small loads, the velocity is controlled by the reaction rates, whereas at high loads the stall pressure is determined by the mechanical properties of the branched actin network. The behavior is consistent with experiments and with our recently proposed self-diffusiophoretic mechanism for actin-polymerization-driven motility. New in vitro experiments to measure the force-velocity relation are proposed.

The moderating effect of psychosocial factors in the relation between neighborhood walkability and children's physical activity.

PubMed

D'Haese, Sara; Gheysen, Freja; De Bourdeaudhuij, Ilse; Deforche, Benedicte; Van Dyck, Delfien; Cardon, Greet

2016-12-09

The study aimed to investigate if psychosocial factors moderate the association between objective walkability and different domains of children's physical activity (PA). A second aim of the study was to investigate the direct associations between psychosocial factors and children's PA. Based on previous literature, it was hypothesized that walkability would be more strongly related to PA among children with negative psychosocial profiles. Data were collected between December 2011 and May 2013 as part of the Belgian Environmental Physical Activity Study in children (BEPAS-child). In total, data from 494 children and one of their parents were included in the study. Children wore an accelerometer for 7 consecutive days and together with one of their parents, they completed the Flemish Physical Activity Questionnaire. Parents filled out a questionnaire concerning their child's psychosocial factors toward PA (i.e. parental attitude toward their child's PA, parental social norm toward their child's PA, parental support, friend support, children's self-efficacy, and perceived benefits and barriers toward sports and PA). Neighborhood walkability was calculated using geographical information systems (GIS). Multilevel cross-classified analyses were conducted. Of the 42 investigated interactions between neighborhood walkability and psychosocial factors in relation to PA among children, only 7 significant interactions were found of which 3 were only significant among children from low-income neighborhoods. Parental support and self-efficacy were positive correlates of children's PA in high- and low-income neighborhoods independent of the level of walkability, but effect sizes were small. The hypothesis that walkability would be more strongly related to PA among children with negative psychosocial profiles could not be confirmed and in general, psychosocial factors and objective walkability did not interact in relation to children's PA. Focusing on parental support and self-efficacy towards PA can possibly cause small effects on children's PA in both high- and low-walkable neighborhoods, as well as in high- and low-income neighborhoods.

The high performance parallel algorithm for Unified Gas-Kinetic Scheme

NASA Astrophysics Data System (ADS)

Li, Shiyi; Li, Qibing; Fu, Song; Xu, Jinxiu

2016-11-01

A high performance parallel algorithm for UGKS is developed to simulate three-dimensional flows internal and external on arbitrary grid system. The physical domain and velocity domain are divided into different blocks and distributed according to the two-dimensional Cartesian topology with intra-communicators in physical domain for data exchange and other intra-communicators in velocity domain for sum reduction to moment integrals. Numerical results of three-dimensional cavity flow and flow past a sphere agree well with the results from the existing studies and validate the applicability of the algorithm. The scalability of the algorithm is tested both on small (1-16) and large (729-5832) scale processors. The tested speed-up ratio is near linear ashind thus the efficiency is around 1, which reveals the good scalability of the present algorithm.

Magnetic particle imaging for radiation-free, sensitive and high-contrast vascular imaging and cell tracking.

PubMed

Zhou, Xinyi Y; Tay, Zhi Wei; Chandrasekharan, Prashant; Yu, Elaine Y; Hensley, Daniel W; Orendorff, Ryan; Jeffris, Kenneth E; Mai, David; Zheng, Bo; Goodwill, Patrick W; Conolly, Steven M

2018-05-10

Magnetic particle imaging (MPI) is an emerging ionizing radiation-free biomedical tracer imaging technique that directly images the intense magnetization of superparamagnetic iron oxide nanoparticles (SPIOs). MPI offers ideal image contrast because MPI shows zero signal from background tissues. Moreover, there is zero attenuation of the signal with depth in tissue, allowing for imaging deep inside the body quantitatively at any location. Recent work has demonstrated the potential of MPI for robust, sensitive vascular imaging and cell tracking with high contrast and dose-limited sensitivity comparable to nuclear medicine. To foster future applications in MPI, this new biomedical imaging field is welcoming researchers with expertise in imaging physics, magnetic nanoparticle synthesis and functionalization, nanoscale physics, and small animal imaging applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

Image Guidance to Aid Pedicle Screw Fixation of a Lumbar Fracture-Dislocation Injury in a Toddler.

PubMed

Houten, John K; Nahkla, Jonathan; Ghandi, Shashank

2017-09-01

Pedicle screw fixation of the lumbar spine in children age <2 years is particularly challenging, as successful cannulation of the small pedicle dimensions requires a high level of precision and there are no implants specifically designed for the infant spine. Image-guided navigation is commonly used in adult spinal surgery and may be particularly helpful for the placement of spinal screws in areas where the bony anatomy is small and/or anatomically complex, as in the upper cervical area. A 19-month-old female presented with a fracture-dislocation injury of L1-2. Intraoperative imaging using the O-arm multidimensional imaging system was networked to a workstation, and neuronavigation was used to place pedicle instrumentation with 3.5-mm-diameter polyaxial screws designed for posterior cervical fixation. At a 48-month follow-up, the patient was neurologically intact, demonstrated normal physical development, and was engaging in normal physical activity for her age. Radiographs obtained approximately 4 years postsurgery showed no evidence of loss for fixation. Image-guided placement of pedicle screws may be a useful aid in achieving accurate and safe fixation in the small dimensions of the infant spine. Copyright © 2017 Elsevier Inc. All rights reserved.

Physical characterization of aerosol particles during the Chinese New Year’s firework events

NASA Astrophysics Data System (ADS)

Zhang, Min; Wang, Xuemei; Chen, Jianmin; Cheng, Tiantao; Wang, Tao; Yang, Xin; Gong, Youguo; Geng, Fuhai; Chen, Changhong

2010-12-01

Measurements for particles 10 nm to 10 μm were taken using a Wide-range Particle Spectrometer during the Chinese New Year (CNY) celebrations in 2009 in Shanghai, China. These celebrations provided an opportunity to study the number concentration and size distribution of particles in an especial atmospheric pollution situation due to firework displays. The firework activities had a clear contribution to the number concentration of small accumulation mode particles (100-500 nm) and PM 1 mass concentration, with a maximum total number concentration of 3.8 × 10 4 cm -3. A clear shift of particles from nucleation and Aitken mode to small accumulation mode was observed at the peak of the CNY firework event, which can be explained by reduced atmospheric lifetimes of smaller particles via the concept of the coagulation sink. High particle density (2.7 g cm -3) was identified as being particularly characteristic of the firework aerosols. Recalculated fine particles PM 1 exhibited on average above 150 μg m -3 for more than 12 hours, which was a health risk to susceptible individuals. Integral physical parameters of firework aerosols were calculated for understanding their physical properties and further model simulation.

Twenty-five year socioeconomic trends in leisure-time and commuting physical activity among employed Finns.

PubMed

Mäkinen, T; Borodulin, K; Laatikainen, T; Fogelholm, M; Prättälä, R

2009-04-01

The trend of socioeconomic differences in physical activity is largely unknown in Finland. In this study, we examined socioeconomic trends in leisure-time and commuting physical activity among Finns in 1978-2002. Nationwide data were derived from an annually repeated cross-sectional Finnish Adult Health Behavior Survey. People under the age of 25, students, the unemployed, and retirees were excluded from the analysis. The final data set included 25 513 women and 25 302 men. Socioeconomic variables included education, occupation, and household income. Odds ratios for being physically active and 95% confidence intervals were calculated. People with the lowest income were less leisure-time and commuting physically active. Among women, low occupational status was associated with high commuting physical activity whereas among men such an association was not found. No educational differences among men in leisure-time and commuting physical activity over time were found. Some indications were found that educational differences in leisure-time physical activity among women might have been reversed. Our data suggest that socioeconomic differences in leisure-time and commuting physical activity are quite small and have remained similar between 1978 and 2002.

In silico screening of drug-membrane thermodynamics reveals linear relations between bulk partitioning and the potential of mean force

NASA Astrophysics Data System (ADS)

Menichetti, Roberto; Kanekal, Kiran H.; Kremer, Kurt; Bereau, Tristan

2017-09-01

The partitioning of small molecules in cell membranes—a key parameter for pharmaceutical applications—typically relies on experimentally available bulk partitioning coefficients. Computer simulations provide a structural resolution of the insertion thermodynamics via the potential of mean force but require significant sampling at the atomistic level. Here, we introduce high-throughput coarse-grained molecular dynamics simulations to screen thermodynamic properties. This application of physics-based models in a large-scale study of small molecules establishes linear relationships between partitioning coefficients and key features of the potential of mean force. This allows us to predict the structure of the insertion from bulk experimental measurements for more than 400 000 compounds. The potential of mean force hereby becomes an easily accessible quantity—already recognized for its high predictability of certain properties, e.g., passive permeation. Further, we demonstrate how coarse graining helps reduce the size of chemical space, enabling a hierarchical approach to screening small molecules.

Physics-Based Fragment Acceleration Modeling for Pressurized Tank Burst Risk Assessments

NASA Technical Reports Server (NTRS)

Manning, Ted A.; Lawrence, Scott L.

2014-01-01

As part of comprehensive efforts to develop physics-based risk assessment techniques for space systems at NASA, coupled computational fluid and rigid body dynamic simulations were carried out to investigate the flow mechanisms that accelerate tank fragments in bursting pressurized vessels. Simulations of several configurations were compared to analyses based on the industry-standard Baker explosion model, and were used to formulate an improved version of the model. The standard model, which neglects an external fluid, was found to agree best with simulation results only in configurations where the internal-to-external pressure ratio is very high and fragment curvature is small. The improved model introduces terms that accommodate an external fluid and better account for variations based on circumferential fragment count. Physics-based analysis was critical in increasing the model's range of applicability. The improved tank burst model can be used to produce more accurate risk assessments of space vehicle failure modes that involve high-speed debris, such as exploding propellant tanks and bursting rocket engines.

Open Access Publishing in High-Energy Physics: the SCOAP3 Initiative

NASA Astrophysics Data System (ADS)

Mele, S.

2010-10-01

Scholarly communication in High-Energy Physics (HEP) shows traits very similar to Astronomy and Astrophysics: pervasiveness of Open Access to preprints through community-based services; a culture of openness and sharing among its researchers; a compact number of yearly articles published by a relatively small number of journals which are dear to the community. These aspects have led HEP to spearhead an innovative model for the transition of its scholarly publishing to Open Access. The Sponsoring Consortium for Open Access Publishing in Particle Physics (SCOAP) aims to be a central body to finance peer-review service rather than the purchase of access to information as in the traditional subscription model, with all articles in the discipline eventually available in Open Access. Sustainable funding to SCOAP would come from libraries, library consortia and HEP funding agencies, through a re-direction of funds currently spent for subscriptions to HEP journals. This paper presents the cultural and bibliometric factors at the roots of SCOAP and the current status of this worldwide initiative.

Validity of High School Physic Module With Character Values Using Process Skill Approach In STKIP PGRI West Sumatera

NASA Astrophysics Data System (ADS)

Anaperta, M.; Helendra, H.; Zulva, R.

2018-04-01

This study aims to describe the validity of physics module with Character Oriented Values Using Process Approach Skills at Dynamic Electrical Material in high school physics / MA and SMK. The type of research is development research. The module development model uses the development model proposed by Plomp which consists of (1) preliminary research phase, (2) the prototyping phase, and (3) assessment phase. In this research is done is initial investigation phase and designing. Data collecting technique to know validation is observation and questionnaire. In the initial investigative phase, curriculum analysis, student analysis, and concept analysis were conducted. In the design phase and the realization of module design for SMA / MA and SMK subjects in dynamic electrical materials. After that, the formative evaluation which include self evaluation, prototyping (expert reviews, one-to-one, and small group. At this stage validity is performed. This research data is obtained through the module validation sheet, which then generates a valid module.

Fluid Mechanics and Heat Transfer of Liquid Precursor Droplets Injected into High-Temperature Plasmas

NASA Astrophysics Data System (ADS)

Basu, Saptarshi; Jordan, Eric H.; Cetegen, Baki M.

2008-03-01

Thermo-physical processes in liquid ceramic precursor droplets in plasma were modeled. Models include aerodynamic droplet break-up, droplet transport, as well as heat and mass transfer within individual droplets. Droplet size, solute concentration, and plasma temperature effects are studied. Results are discussed with the perspective of selecting processing conditions and injection parameters to obtain certain types of coating microstructures. Small droplets (<5 microns) are found to undergo volumetric precipitation and coating deposition with small unpyrolized material. Droplets can be made to undergo shear break-up by reducing surface tension and small droplets promote volumetric precipitation. Small particles reach substrate as molten splats resulting in denser coatings. Model predicts that larger droplets (>5 microns) tend to surface precipitate-forming shells with liquid core. They may be subjected to internal pressurization leading to shattering of shells and secondary atomization of liquid within. They arrive at the substrate as broken shells and unpyrolized material.

Single Electron Tunneling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ruggiero, Steven T.

Financial support for this project has led to advances in the science of single-electron phenomena. Our group reported the first observation of the so-called ''Coulomb Staircase'', which was produced by tunneling into ultra-small metal particles. This work showed well-defined tunneling voltage steps of width e/C and height e/RC, demonstrating tunneling quantized on the single-electron level. This work was published in a now well-cited Physical Review Letter. Single-electron physics is now a major sub-field of condensed-matter physics, and fundamental work in the area continues to be conducted by tunneling in ultra-small metal particles. In addition, there are now single-electron transistors thatmore » add a controlling gate to modulate the charge on ultra-small photolithographically defined capacitive elements. Single-electron transistors are now at the heart of at least one experimental quantum-computer element, and single-electron transistor pumps may soon be used to define fundamental quantities such as the farad (capacitance) and the ampere (current). Novel computer technology based on single-electron quantum dots is also being developed. In related work, our group played the leading role in the explanation of experimental results observed during the initial phases of tunneling experiments with the high-temperature superconductors. When so-called ''multiple-gap'' tunneling was reported, the phenomenon was correctly identified by our group as single-electron tunneling in small grains in the material. The main focus throughout this project has been to explore single electron phenomena both in traditional tunneling formats of the type metal/insulator/particles/insulator/metal and using scanning tunneling microscopy to probe few-particle systems. This has been done under varying conditions of temperature, applied magnetic field, and with different materials systems. These have included metals, semi-metals, and superconductors. Amongst a number of results, we have verified that clusters of down to one, two, and three metal atoms can be identified with single-electron techniques. We have also, extended the regime of single-electron phenomenology through the observation of single-electron effects in metal droplets in the high-conductance regime.« less

Long-term high-level exercise promotes muscle reinnervation with age.

PubMed

Mosole, Simone; Carraro, Ugo; Kern, Helmut; Loefler, Stefan; Fruhmann, Hannah; Vogelauer, Michael; Burggraf, Samantha; Mayr, Winfried; Krenn, Matthias; Paternostro-Sluga, Tatjana; Hamar, Dusan; Cvecka, Jan; Sedliak, Milan; Tirpakova, Veronika; Sarabon, Nejc; Musarò, Antonio; Sandri, Marco; Protasi, Feliciano; Nori, Alessandra; Pond, Amber; Zampieri, Sandra

2014-04-01

The histologic features of aging muscle suggest that denervation contributes to atrophy, that immobility accelerates the process, and that routine exercise may protect against loss of motor units and muscle tissue. Here, we compared muscle biopsies from sedentary and physically active seniors and found that seniors with a long history of high-level recreational activity up to the time of muscle biopsy had 1) lower loss of muscle strength versus young men (32% loss in physically active vs 51% loss in sedentary seniors); 2) fewer small angulated (denervated) myofibers; 3) a higher percentage of fiber-type groups (reinnervated muscle fibers) that were almost exclusive of the slow type; and 4) sparse normal-size muscle fibers coexpressing fast and slow myosin heavy chains, which is not compatible with exercise-driven muscle-type transformation. The biopsies from the old physically active seniors varied from sparse fiber-type groupings to almost fully transformed muscle, suggesting that coexpressing fibers appear to fill gaps. Altogether, the data show that long-term physical activity promotes reinnervation of muscle fibers and suggest that decades of high-level exercise allow the body to adapt to age-related denervation by saving otherwise lost muscle fibers through selective recruitment to slow motor units. These effects on size and structure of myofibers may delay functional decline in late aging.

ECCE Toolkit: Prototyping Sensor-Based Interaction.

PubMed

Bellucci, Andrea; Aedo, Ignacio; Díaz, Paloma

2017-02-23

Building and exploring physical user interfaces requires high technical skills and hours of specialized work. The behavior of multiple devices with heterogeneous input/output channels and connectivity has to be programmed in a context where not only the software interface matters, but also the hardware components are critical (e.g., sensors and actuators). Prototyping physical interaction is hindered by the challenges of: (1) programming interactions among physical sensors/actuators and digital interfaces; (2) implementing functionality for different platforms in different programming languages; and (3) building custom electronic-incorporated objects. We present ECCE (Entities, Components, Couplings and Ecosystems), a toolkit for non-programmers that copes with these issues by abstracting from low-level implementations, thus lowering the complexity of prototyping small-scale, sensor-based physical interfaces to support the design process. A user evaluation provides insights and use cases of the kind of applications that can be developed with the toolkit.

ECCE Toolkit: Prototyping Sensor-Based Interaction

PubMed Central

Bellucci, Andrea; Aedo, Ignacio; Díaz, Paloma

2017-01-01

Building and exploring physical user interfaces requires high technical skills and hours of specialized work. The behavior of multiple devices with heterogeneous input/output channels and connectivity has to be programmed in a context where not only the software interface matters, but also the hardware components are critical (e.g., sensors and actuators). Prototyping physical interaction is hindered by the challenges of: (1) programming interactions among physical sensors/actuators and digital interfaces; (2) implementing functionality for different platforms in different programming languages; and (3) building custom electronic-incorporated objects. We present ECCE (Entities, Components, Couplings and Ecosystems), a toolkit for non-programmers that copes with these issues by abstracting from low-level implementations, thus lowering the complexity of prototyping small-scale, sensor-based physical interfaces to support the design process. A user evaluation provides insights and use cases of the kind of applications that can be developed with the toolkit. PMID:28241502

Examining the Error of Mis-Specifying Nonlinear Confounding Effect With Application on Accelerometer-Measured Physical Activity.

PubMed

Lee, Paul H

2017-06-01

Some confounders are nonlinearly associated with dependent variables, but they are often adjusted using a linear term. The purpose of this study was to examine the error of mis-specifying the nonlinear confounding effect. We carried out a simulation study to investigate the effect of adjusting for a nonlinear confounder in the estimation of a causal relationship between the exposure and outcome in 3 ways: using a linear term, binning into 5 equal-size categories, or using a restricted cubic spline of the confounder. Continuous, binary, and survival outcomes were simulated. We examined the confounder across varying measurement error. In addition, we performed a real data analysis examining the 3 strategies to handle the nonlinear effects of accelerometer-measured physical activity in the National Health and Nutrition Examination Survey 2003-2006 data. The mis-specification of a nonlinear confounder had little impact on causal effect estimation for continuous outcomes. For binary and survival outcomes, this mis-specification introduced bias, which could be eliminated using spline adjustment only when there is small measurement error of the confounder. Real data analysis showed that the associations between high blood pressure, high cholesterol, and diabetes and mortality adjusted for physical activity with restricted cubic spline were about 3% to 11% larger than their counterparts adjusted with a linear term. For continuous outcomes, confounders with nonlinear effects can be adjusting with a linear term. Spline adjustment should be used for binary and survival outcomes on confounders with small measurement error.

Comparing the physical demands of friendly matches and small-sided games in semiprofessional soccer players.

PubMed

Casamichana, David; Castellano, Julen; Castagna, Carlo

2012-03-01

This study compared the physical demands of friendly matches (FMs) and small-sided games (SGs) in semiprofessional soccer players by means of global positioning system technology. Twenty-seven semiprofessional soccer players were monitored during 7 FMs and 9 sessions involving different SGs. Their physical profile was described on the basis of 20 variables related to distances and frequencies at different running speeds, the number of accelerations, and through global indicators of workload such as the work:rest ratio, player workload, and the exertion index. Results showed significant differences (p < 0.01) between SGs and FMs for the following variables: overall workload (SG > FM); the distribution of the distance covered in the speed zones 7.0-12.9 km·h(-1) (SG > FM) and >21 km·h(-1) (FM > SG); the distribution of time spent in certain speed zones (FM > SG: 0.0-6.9 and >21 km·h(-1); FM > SG: 7.0-12.9 km·h(-1)). More sprints per hour of play were performed during FMs, with greater mean durations and distances, greater maximum durations and distances, and a greater frequency per hour of play for sprints of 10-40 and >40 m (p < 0.01). The frequency of repeated high-intensity efforts was higher during FM (p < 0.01). The results show that coaches and strength and conditioning professionals should consider FMs during their training routine to foster specific adaptations in the domain of high-intensity effort.

The Study of Small Groups and Microevolution: A Project for Physical Anthropology.

ERIC Educational Resources Information Center

Rice, Patricia C.

1985-01-01

Describes a hands-on project in which anthropology students play the role of professional physical anthropologist in collecting and analyzing data on a small group of contemporary humans. Use of simulated data to represent ancestral populations results in an analysis of microevolution. (KH)

Within-person associations of young adolescents' physical activity across five primary locations: is there evidence of cross-location compensation?

PubMed

Carlson, Jordan A; Mitchell, Tarrah B; Saelens, Brian E; Staggs, Vincent S; Kerr, Jacqueline; Frank, Lawrence D; Schipperijn, Jasper; Conway, Terry L; Glanz, Karen; Chapman, Jim E; Cain, Kelli L; Sallis, James F

2017-04-20

Youth are active in multiple locations, but it is unknown whether more physical activity in one location is associated with less in other locations. This cross-sectional study examines whether on days with more physical activity in a given location, relative to their typical activity in that location, youth had less activity in other locations (i.e., within-person associations/compensation). Participants were 528 adolescents, ages 12 to 16 (M = 14.12, SD = 1.44, 50% boys, 70% White non-Hispanic). Accelerometer and Global Positioning System devices were used to measure the proportion of time spent in moderate-to-vigorous physical activity (MVPA) in five locations: home, home neighborhood, school, school neighborhood, and other locations. Mixed-effects regression was used to examine within-person associations of MVPA across locations and moderators of these associations. Two of ten within-participant associations tested indicated small amounts of compensation, and one association indicated generalization across locations. Higher at-school MVPA (relative to the participant's average) was related to less at-home MVPA and other-location MVPA (Bs = -0.06 min/day). Higher home-neighborhood MVPA (relative to the participant's average) was related to more at-home MVPA (B = 0.07 min/day). Some models showed that compensation was more likely (or generalization less likely) in boys and non-whites or Hispanic youth. Consistent evidence of compensation across locations was not observed. A small amount of compensation was observed for school physical activity, suggesting that adolescents partially compensated for high amounts of school activity by being less active in other locations. Conversely, home-neighborhood physical activity appeared to carry over into the home, indicating a generalization effect. Overall these findings suggest that increasing physical activity in one location is unlikely to result in meaningful decreases in other locations. Supporting physical activity across multiple locations is critical to increasing overall physical activity in youth.

Energy metabolism, body composition, and urea generation rate in hemodialysis patients.

PubMed

Sridharan, Sivakumar; Vilar, Enric; Berdeprado, Jocelyn; Farrington, Ken

2013-10-01

Hemodialysis (HD) adequacy is currently assessed using normalized urea clearance (Kt/V), although scaling based on Watson volume (V) may disadvantage women and men with low body weight. Alternative scaling factors such as resting energy expenditure and high metabolic rate organ mass have been suggested. The relationship between such factors and uremic toxin generation has not been established. We aimed to study the relationship between body size, energy metabolism, and urea generation rate. A cross-sectional cohort of 166 HD patients was studied. Anthropometric measurements were carried on all. Resting energy expenditure was measured by indirect calorimetry, fat-free mass by bio-impedance and total energy expenditure by combining resting energy expenditure with a questionnaire-derived physical activity data. High metabolic rate organ mass was calculated using a published equation and urea generation rate using formal urea kinetic modeling. Metabolic factors including resting energy expenditure, total energy expenditure and fat-free mass correlated better with urea generation rate than did Watson volume. Total energy expenditure and fat-free mass (but not Watson Volume) were independent predictors of urea generation rate, the model explaining 42% of its variation. Small women (

Small-x physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mueller, A.H.

1997-06-01

After a brief review of the kinematics of deep inelastic lepton-proton scattering, the parton model is described. Small-x behavior coming from DGLAP evolution and from BFKL evolution is discussed, and the two types of evolution are contrasted and compared. Then a more detailed discussion of BFKL dynamics is given. The phenomenology of small-x physics is discussed with an emphasis on ways in which BFKL dynamics may be discussed and measured. 45 refs., 12 figs.

The Inner Coma Physical Environments of Ecliptic Comets 45P/Honda-Mrkos-Pajdusakova, 2P/Encke, and 41P/Tuttle-Giacobini-Kresak Revealed Through Long-Slit Spectroscopy at NASA IRTF

NASA Astrophysics Data System (ADS)

Bonev, Boncho P.; DiSanti, Michael A.; Roth, Nathan; Dello Russo, Neil; Vervack, Ronald J.; Gibb, Erika L.; Villanueva, Geronimo Luis; Combi, Michael R.; Fougere, Nicolas; Kawakita, Hideyo; McKay, Adam J.; Saki, Mohammad; Cordiner, Martin; Protopapa, Silvia; de Val-Borro, Miguel

2017-10-01

Understanding the physical processes in the inner regions of cometary atmospheres is vital for interpretation of molecular cometary emission at all wavelengths. Furthermore, because ecliptic comets are continuously evaluated as space mission targets, understanding their coma environments is a central theme in both enhancing the science return of past missions (EPOXI, Rosetta) and in selecting future mission targets. With this motivation, we report long-slit high-resolution observations of H2O emission in the comae of three ecliptic comets observed in early 2017: 45P/Honda-Mrkos-Pajdusakova, 2P/Encke, and 41P/Tuttle-Giacobini-Kresak. Using the new crossed-dispersed spectrograph iSHELL at NASA IRTF, we detected a suite of water rovibrational emission lines from these comets and measured the spatial distributions of H2O rotational temperatures and molecular column densities. Both parameters are highly diagnostic of the physical environment in cometary comae, the competition between cooling and heating processes in these environments, and the presence (or lack thereof) of extended coma sources of gas-phase H2O. Comets 2P and 45P allowed a rare glimpse into coma physics at small (< 0.6 AU) heliocentric distances, where photochemical heating is particularly important, but direct H2O observations have been sparse. Our results add to the small sample of spatial-spectral measurements of this type. They will be discussed in the context of coma physics models along with prospects for investigations during the upcoming favorable apparitions of ecliptic comets 21P/Giacobini-Zinner and 46P/Wirtanen. We gratefully acknowledge support from the NASA Solar System Workings, Planetary Atmospheres, Earth and Space Science Fellowship, Solar System Observations, Emerging Worlds, and Astrobiology Programs, and NSF Solar and Planetary Research Grants. We are grateful to the entire IRTF staff for their help with these challenging observations, most of which were done during daytime.

Perspective: Aerosol microphysics: From molecules to the chemical physics of aerosols

NASA Astrophysics Data System (ADS)

Bzdek, Bryan R.; Reid, Jonathan P.

2017-12-01

Aerosols are found in a wide diversity of contexts and applications, including the atmosphere, pharmaceutics, and industry. Aerosols are dispersions of particles in a gas, and the coupling of the two phases results in highly dynamic systems where chemical and physical properties like size, composition, phase, and refractive index change rapidly in response to environmental perturbations. Aerosol particles span a wide range of sizes from 1 nm to tens of micrometres or from small molecular clusters that may more closely resemble gas phase molecules to large particles that can have similar qualities to bulk materials. However, even large particles with finite volumes exhibit distinct properties from the bulk condensed phase, due in part to their higher surface-to-volume ratio and their ability to easily access supersaturated solute states inaccessible in the bulk. Aerosols represent a major challenge for study because of the facile coupling between the particle and gas, the small amounts of sample available for analysis, and the sheer breadth of operative processes. Time scales of aerosol processes can be as short as nanoseconds or as long as years. Despite their very different impacts and applications, fundamental chemical physics processes serve as a common theme that underpins our understanding of aerosols. This perspective article discusses challenges in the study of aerosols and highlights recent chemical physics advancements that have enabled improved understanding of these complex systems.

A source of antihydrogen for in-flight hyperfine spectroscopy

PubMed Central

Kuroda, N.; Ulmer, S.; Murtagh, D. J.; Van Gorp, S.; Nagata, Y.; Diermaier, M.; Federmann, S.; Leali, M.; Malbrunot, C.; Mascagna, V.; Massiczek, O.; Michishio, K.; Mizutani, T.; Mohri, A.; Nagahama, H.; Ohtsuka, M.; Radics, B.; Sakurai, S.; Sauerzopf, C.; Suzuki, K.; Tajima, M.; Torii, H. A.; Venturelli, L.; Wu¨nschek, B.; Zmeskal, J.; Zurlo, N.; Higaki, H.; Kanai, Y.; Lodi Rizzini, E.; Nagashima, Y.; Matsuda, Y.; Widmann, E.; Yamazaki, Y.

2014-01-01

Antihydrogen, a positron bound to an antiproton, is the simplest antiatom. Its counterpart—hydrogen—is one of the most precisely investigated and best understood systems in physics research. High-resolution comparisons of both systems provide sensitive tests of CPT symmetry, which is the most fundamental symmetry in the Standard Model of elementary particle physics. Any measured difference would point to CPT violation and thus to new physics. Here we report the development of an antihydrogen source using a cusp trap for in-flight spectroscopy. A total of 80 antihydrogen atoms are unambiguously detected 2.7 m downstream of the production region, where perturbing residual magnetic fields are small. This is a major step towards precision spectroscopy of the ground-state hyperfine splitting of antihydrogen using Rabi-like beam spectroscopy. PMID:24448273

A Massively Parallel Particle Code for Rarefied Ionized and Neutral Gas Flows in Earth and Planetary Atmospheres, Ionospheres and Magnetospheres

NASA Technical Reports Server (NTRS)

Combi, Michael R.

2004-01-01

In order to understand the global structure, dynamics, and physical and chemical processes occurring in the upper atmospheres, exospheres, and ionospheres of the Earth, the other planets, comets and planetary satellites and their interactions with their outer particles and fields environs, it is often necessary to address the fundamentally non-equilibrium aspects of the physical environment. These are regions where complex chemistry, energetics, and electromagnetic field influences are important. Traditional approaches are based largely on hydrodynamic or magnetohydrodynamic MHD) formulations and are very important and highly useful. However, these methods often have limitations in rarefied physical regimes where the molecular collision rates and ion gyrofrequencies are small and where interactions with ionospheres and upper neutral atmospheres are important.

ASSESSMENT OF TWO PHYSICALLY BASED WATERSHED MODELS BASED ON THEIR PERFORMANCES OF SIMULATING SEDIMENT MOVEMENT OVER SMALL WATERSHEDS

EPA Science Inventory

Abstract: Two physically based and deterministic models, CASC2-D and KINEROS are evaluated and compared for their performances on modeling sediment movement on a small agricultural watershed over several events. Each model has different conceptualization of a watershed. CASC...

An Apparatus for Growth of Small Crystals From Solutions.

ERIC Educational Resources Information Center

Mitrovic, Mico M.

1995-01-01

Describes an apparatus for crystal growth that was designed to study growth kinetics of small crystals from solutions and to obtain crystals of various substances. Describes the use of the apparatus in laboratory practical experiments in the field of crystal growth physics within the course "Solid State Physics". (JRH)

SMALL MAMMALS: CONSEQUENCES OF STOCHASTIC DATA VARIATION FOR MODELING INDICATORS OF HABITAT SUITABILITY FOR A WELL-STUDIED RESOURCE

EPA Science Inventory

Increasingly, models of physical habitat variables (i.e. vegetation, soil) are utilized as indicators of small mammal habitat suitability or quality. Presumably, use of physical habitat models indicating habitat suitability or quality would be improved and enhanced by the extens...

Microenergetic Shock Initiation Studies on Deposited Films of PETN

NASA Astrophysics Data System (ADS)

Tappan, Alexander S.; Wixom, Ryan R.; Trott, Wayne M.; Long, Gregory T.; Knepper, Robert; Brundage, Aaron L.; Jones, David A.

2009-06-01

Films of the high explosive PETN (pentaerythritol tetranitrate) up to 500-μm thick have been deposited through physical vapor deposition, with the intent of creating well-defined samples for shock-initiation studies. PETN films were characterized with surface profilometry, scanning electron microscopy, x-ray diffraction, and focused ion beam nanotomography. These high-density films were subjected to strong shocks in both the in-plane and out-of-plane orientations. Initiation behavior was monitored with high-speed framing and streak camera photography. Direct initiation with a donor explosive (either RDX with binder, or CL-20 with binder) was possible in both orientations, but with the addition of a thin aluminum buffer plate (in-plane configuration only), initiation proved to be difficult due to the attenuated shock and the high density of the PETN films. Mesoscale models of microenergetic samples were created using the shock physics code CTH and compared with experimental results. The results of these experiments will be discussed in the context of small sample geometry, deposited film morphology, and density.

Wireless data transmission for high energy physics applications

NASA Astrophysics Data System (ADS)

Dittmeier, Sebastian; Brenner, Richard; Dancila, Dragos; Dehos, Cedric; De Lurgio, Patrick; Djurcic, Zelimir; Drake, Gary; Gonzalez Gimenez, Jose Luis; Gustafsson, Leif; Kim, Do-Won; Locci, Elizabeth; Pfeiffer, Ullrich; Röhrich, Dieter; Rydberg, Anders; Schöning, André; Siligaris, Alexandre; Soltveit, Hans Kristian; Ullaland, Kjetil; Vincent, Pierre; Rodriguez Vazquez, Pedro; Wiedner, Dirk; Yang, Shiming

2017-08-01

Silicon tracking detectors operated at high luminosity collider experiments pose a challenge for current and future readout systems regarding bandwidth, radiation, space and power constraints. With the latest developments in wireless communications, wireless readout systems might be an attractive alternative to commonly used wired optical and copper based readout architectures. The WADAPT group (Wireless Allowing Data and Power Transmission) has been formed to study the feasibility of wireless data transmission for future tracking detectors. These proceedings cover current developments focused on communication in the 60 GHz band. This frequency band offers a high bandwidth, a small form factor and an already mature technology. Motivation for wireless data transmission for high energy physics application and the developments towards a demonstrator prototype are summarized. Feasibility studies concerning the construction and operation of a wireless transceiver system have been performed. Data transmission tests with a transceiver prototype operating at even higher frequencies in the 240 GHz band are described. Data transmission at rates up to 10 Gb/s have been obtained successfully using binary phase shift keying.

Electro-optical design of a long slit streak tube

NASA Astrophysics Data System (ADS)

Tian, Liping; Tian, Jinshou; Wen, Wenlong; Chen, Ping; Wang, Xing; Hui, Dandan; Wang, Junfeng

2017-11-01

A small size and long slit streak tube with high spatial resolution was designed and optimized. Curved photocathode and screen were adopted to increase the photocathode working area and spatial resolution. High physical temporal resolution obtained by using a slit accelerating electrode. Deflection sensitivity of the streak tube was improved by adopting two-folded deflection plates. The simulations indicate that the photocathode effective working area can reach 30mm × 5mm. The static spatial resolution is higher than 40lp/mm and 12lp/mm along scanning and slit directions respectively while the physical temporal resolution is higher than 60ps. The magnification is 0.75 and 0.77 in scanning and slit directions. And also, the deflection sensitivity is as high as 37mm/kV. The external dimension of the streak tube are only ∅74mm×231mm. Thus, it can be applied to laser imaging radar system for large field of view and high range precision detection.

A New Curriculum for Physics Graduate Students

NASA Astrophysics Data System (ADS)

Griesshammer, Harald W.

2012-03-01

Effective Fall 2008, GW Physics implemented a new graduate curriculum, addressing nation-wide problems: (1) wide gap between 50-year-old curricula and the proficiencies expected to start research; (2) high attrition rates and long times to degree; (3) limited resources in small departments to cover all topics deemed essential. The new curriculum: (1) extends each course to 4 hours weekly for better in-depth coverage and cautious additions; (2) decreases the number of core-courses per semester to 2, with less ``parallel-processing'' of only loosely correlated lectures; (3) increases synergies by stricter logical ordering and synchronisation of courses; (4) frees faculty to regularly offer advanced courses; (5) integrates examples tied to ongoing research in our department; (6) integrates computational methods into core-lectures; (7) encourages focusing on concepts and ``meta-cognitive skills'' in studio-like settings. The new curriculum and qualifying exam, its rationale and assessment criteria will be discussed. This concept is tailored to the needs of small departments with only a few research fields and a close student-teacher relationship.

Messages for men: the efficacy of EPPM-based messages targeting men's physical activity.

PubMed

Hatchell, Alexandra C; Bassett-Gunter, Rebecca L; Clarke, Marie; Kimura, Stacey; Latimer-Cheung, Amy E

2013-01-01

The majority of men are insufficiently active. Men's tendencies to participate in risky behaviors and their inactivity likely contribute to their increased risk of morbidity and mortality. Physical activity decreases the risk of developing many chronic diseases and may be an optimal behavior to target in men's health interventions. However, educational resources promoting physical activity for men are lacking. To address this gap, we tested the efficacy of messages based upon the Extended Parallel Process Model (EPPM; Witte, 1992) to increase men's physical activity intentions and behaviors. Men who were not meeting physical activity guidelines (n = 611) were randomly assigned to read high or low efficacy physical activity messages paired with high or no health risk information. Participants read four brief messages on four consecutive days. Intentions were assessed at baseline and the first follow-up (Day 5). Manipulation check measures were assessed at Day 5. Behavior was assessed at baseline and the second follow-up (Day 14). Overall, the messages had small sized effects. A completer analysis revealed that although men's intentions to be active increased over the course of the study regardless of the messages they received, only men who received risk information significantly increased their physical activity. Men who received low efficacy and risk information were less likely to meet the physical activity guidelines at Day 14 than men who only received low efficacy information. From these results, we suggest preliminary recommendations for the development of physical activity messages for men and areas for future EPPM-based research. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Small forces that differ with prior motor experience can communicate movement goals during human-human physical interaction.

PubMed

Sawers, Andrew; Bhattacharjee, Tapomayukh; McKay, J Lucas; Hackney, Madeleine E; Kemp, Charles C; Ting, Lena H

2017-01-31

Physical interactions between two people are ubiquitous in our daily lives, and an integral part of many forms of rehabilitation. However, few studies have investigated forces arising from physical interactions between humans during a cooperative motor task, particularly during overground movements. As such, the direction and magnitude of interaction forces between two human partners, how those forces are used to communicate movement goals, and whether they change with motor experience remains unknown. A better understanding of how cooperative physical interactions are achieved in healthy individuals of different skill levels is a first step toward understanding principles of physical interactions that could be applied to robotic devices for motor assistance and rehabilitation. Interaction forces between expert and novice partner dancers were recorded while performing a forward-backward partnered stepping task with assigned "leader" and "follower" roles. Their position was recorded using motion capture. The magnitude and direction of the interaction forces were analyzed and compared across groups (i.e. expert-expert, expert-novice, and novice-novice) and across movement phases (i.e. forward, backward, change of direction). All dyads were able to perform the partnered stepping task with some level of proficiency. Relatively small interaction forces (10-30N) were observed across all dyads, but were significantly larger among expert-expert dyads. Interaction forces were also found to be significantly different across movement phases. However, interaction force magnitude did not change as whole-body synchronization between partners improved across trials. Relatively small interaction forces may communicate movement goals (i.e. "what to do and when to do it") between human partners during cooperative physical interactions. Moreover, these small interactions forces vary with prior motor experience, and may act primarily as guiding cues that convey information about movement goals rather than providing physical assistance. This suggests that robots may be able to provide meaningful physical interactions for rehabilitation using relatively small force levels.

Method for producing small hollow spheres

DOEpatents

Hendricks, C.D.

1979-01-09

Method is disclosed for producing small hollow spheres of glass, metal or plastic, wherein the sphere material is mixed with or contains as part of the composition a blowing agent which decomposes at high temperature (T [approx gt] 600 C). As the temperature is quickly raised, the blowing agent decomposes and the resulting gas expands from within, thus forming a hollow sphere of controllable thickness. The thus produced hollow spheres (20 to 10[sup 3] [mu]m) have a variety of application, and are particularly useful in the fabrication of targets for laser implosion such as neutron sources, laser fusion physics studies, and laser initiated fusion power plants. 1 fig.

Method and apparatus for producing small hollow spheres

DOEpatents

Hendricks, Charles D.

1979-01-01

Method and apparatus for producing small hollow spheres of glass, metal or plastic, wherein the sphere material is mixed with or contains as part of the composition a blowing agent which decomposes at high temperature (T.gtoreq.600.degree. C.). As the temperature is quickly raised, the blowing agent decomposes and the resulting gas expands from within, thus forming a hollow sphere of controllable thickness. The thus produced hollow spheres (20 to 10.sup.3 .mu.m) have a variety of application, and are particularly useful in the fabrication of targets for laser implosion such as neutron sources, laser fusion physics studies, and laser initiated fusion power plants.

Method for producing small hollow spheres

DOEpatents

Hendricks, Charles D. [Livermore, CA

1979-01-09

Method for producing small hollow spheres of glass, metal or plastic, wherein the sphere material is mixed with or contains as part of the composition a blowing agent which decomposes at high temperature (T .gtorsim. 600.degree. C). As the temperature is quickly raised, the blowing agent decomposes and the resulting gas expands from within, thus forming a hollow sphere of controllable thickness. The thus produced hollow spheres (20 to 10.sup.3 .mu.m) have a variety of application, and are particularly useful in the fabrication of targets for laser implosion such as neutron sources, laser fusion physics studies, and laser initiated fusion power plants.

Effect of PF impregnation and surface densification on the mechanical properties of small-scale wood laminated poles

Treesearch

Huaqiang Yu; Chung Y. Hse; Zehui Jiang

2009-01-01

The wood poles in the United States are from high-valued trees that are becoming more expensive and less available. Wood laminated composite poles (LCP) are a kind of alternative to solid poles. Considerable interest has developed in last century in the resin impregnation and wood surface densification to improve its physical and mechanical properties. In this...

Big Data with Small Cases: A Method for Discovering Students Centered Contexts for Physics Courses

ERIC Educational Resources Information Center

Bülbül, M. S.

2015-01-01

This article proposes a methodology that could assist teachers in understanding their students' primary needs or interests to decide on the kind of examples or contexts to be used in the classroom. The methodology was tested on 100 volunteers from university (N = 50) and high school (N = 50) in Ankara, Turkey. The participants were asked to write…

Molecular Dynamics Characterization of the Conformational Landscape of Small Peptides: A Series of Hands-On Collaborative Practical Sessions for Undergraduate Students

ERIC Educational Resources Information Center

Rodrigues, João P. G. L. M.; Melquiond, Adrien S. J.; Bonvin, Alexandre M. J. J.

2016-01-01

Molecular modelling and simulations are nowadays an integral part of research in areas ranging from physics to chemistry to structural biology, as well as pharmaceutical drug design. This popularity is due to the development of high-performance hardware and of accurate and efficient molecular mechanics algorithms by the scientific community. These…

Research Projects for Undergraduates

NASA Astrophysics Data System (ADS)

Troncalli, Andra

2010-03-01

Physics majors, by enrolling in our research experience in physics course, have the opportunity to work in small groups on independent research projects. Over the last few years, I have directed a few of these research projects; some were closely related to my own research in the field of high temperature superconductivity, and students participated in growing and characterizing samples. Other projects involved nanotechnology, Hall probes, and programming in LabVIEW. For some students, this was their very first research project, while others had more experience. I will talk about the projects and about the particular type of challenges and benefits this type of course brings to both students and instructors.

Radiative property degradation of water impinging on thermally-controlled surfaces under space conditions.

NASA Technical Reports Server (NTRS)

Maples, D.; Spiller, M. H.; Maples, G.

1973-01-01

Review of the results of an investigation aimed at determining experimentally the directional monochromatic reflectance changes caused under high-vacuum space conditions by a water spray impinging on thermally controlled surfaces consisting of three paint specimens (Z93, S13G, and 92-007) and an aluminum foil. The first two paints and the aluminum foil suffered considerable physical damage, but only small changes resulted in the reflectance of the paints while the reflectance of the aluminum foil decreased with increase in exposure time to the water jet. Only the 92-007 Dow Corning paint retained the same physical and reflective characteristics.

An Inexpensive Method to use an Ocean Optics Spectrometer for Telescopic Spectroscopy

NASA Astrophysics Data System (ADS)

Joel, Berger; Sugerman, B. E. K.

2012-01-01

We present a relatively-inexpensive method for using an Ocean Optics spectrometer for telescopic spectroscopy. The Ocean Optics spectrometer is a highly-sensitive, affordable and versatile fiber-optic spectrometer that can be used in a variety of physics and astronomy classes and labs. With about $275 and a small amount of machining, this spectrometer can be easily adapted for any telescope that accepts 2" eyepieces. We provide the equipment list, machining specs, and calibration process, as well as sample stellar spectra. This work was supported by the Department of Physics and Astronomy and the Office of the Provost of Goucher College.

A flight simulator control system using electric torque motors

NASA Technical Reports Server (NTRS)

Musick, R. O.; Wagner, C. A.

1975-01-01

Control systems are required in flight simulators to provide representative stick and rudder pedal characteristics. A system has been developed that uses electric dc torque motors instead of the more common hydraulic actuators. The torque motor system overcomes certain disadvantages of hydraulic systems, such as high cost, high power consumption, noise, oil leaks, and safety problems. A description of the torque motor system is presented, including both electrical and mechanical design as well as performance characteristics. The system develops forces sufficiently high for most simulations, and is physically small and light enough to be used in most motion-base cockpits.

High pressure gas spheres for neutron and photon experiments

NASA Astrophysics Data System (ADS)

Rupp, G.; Petrich, D.; Käppeler, F.; Kaltenbaek, J.; Leugers, B.; Reifarth, R.

2009-09-01

High pressure gas spheres have been designed and successfully used in several nuclear physics experiments on noble gases. The pros and cons of this solution are the simple design and the high reliability versus the fact that the density is limited to 40-60% of liquid or solid gas samples. Originally produced for neutron capture studies at keV energies, the comparably small mass of the gas spheres were an important advantage, which turned out to be of relevance for other applications as well. The construction, performance, and operation of the spheres are described and examples for their use are presented.

Small-sided games in football as a method to improve high school students’ instep passing skills

NASA Astrophysics Data System (ADS)

Ridwan, M.; Darmawan, G.; Fuadi, Z.

2018-01-01

This study analyzed the influence of small sided games application toward increasing the learning result of instep passing in football. The research used one group pretest-posttest design. The data were obtained once a week for 135 minutes of small sided games and this activity had been held for four weeks with a final test in the final meeting. According to descriptive data result, there were increases of the mean. The data showed the increase of the application of small sided games resulted in not only the mean of the descriptive data but also the result of T-test. The significant of T-test is 0,000. It means less than 0,05 then the hypothesis Ha received and Ho rejected automatically. The presentation showed that 48,15% data is increasing by small-sided games application. The small-sided games were proven to be the right tool to increase instep passing football technique. We suggested to the apply that kind of games of football learning on physical education subject, especially for pre-university students.

Physical inactivity interacts with an endothelial lipase polymorphism to modulate high density lipoprotein cholesterol in the GOLDN study

PubMed Central

Smith, Caren E.; Arnett, Donna K.; Tsai, Michael Y.; Lai, Chao-Qiang; Parnell, Laurence D.; Shen, Jian; Laclaustra, Martin; Junyent, Mireia; Ordovás, José M.

2009-01-01

Background Plasma high density lipoprotein (HDL) cholesterol (HDL-C) concentration is highly heritable but is also modifiable by environmental factors including physical activity. HDL-C response to exercise varies among individuals, and this variability may be associated with genetic polymorphisms in the key regulators of HDL metabolism including endothelial lipase (LIPG). Methods We examined associations between variants LIPG T111I (rs2000813) and LIPG i24582 (rs6507931), HDL and television viewing/computer use (“screen time”) as a marker for physical inactivity in a population with high prevalence of metabolic syndrome. Subjects consisted of 539 White men and 584 women (mean ± S.D., 49 ± 16 years) participating in the GOLDN study. Results We did not observe an association with either LIPG SNP or HDL independently of screen time. In multi-adjusted linear regression models, HDL interacted significantly with screen time as a continuous variable in LIPG i24582 subjects with TT genotype (P < 0.05). By dichotomizing screen time into high and low levels, we found significant genotype-associated differences in HDL in women but not men. When screen time was ≥2.6 h/day, the concentrations of total HDL-C, large HDL, large low density lipoprotein (LDL) were lower, the concentration of small LDL was higher and HDL and LDL particle sizes were smaller in subjects with LIPG i24582 TT compared to CT and CC subjects (P < 0.05). Conclusions We found a significant gene-physical inactivity interaction for HDL and some LDL measures for the LIPG i24582 polymorphism. Higher levels of physical activity may be protective for HDL-C concentrations and low activity detrimental in LIPG i24582 TT individuals, especially in women. PMID:19380136

Physical inactivity interacts with an endothelial lipase polymorphism to modulate high density lipoprotein cholesterol in the GOLDN study.

PubMed

Smith, Caren E; Arnett, Donna K; Tsai, Michael Y; Lai, Chao-Qiang; Parnell, Laurence D; Shen, Jian; Laclaustra, Martin; Junyent, Mireia; Ordovás, José M

2009-10-01

Plasma high density lipoprotein (HDL) cholesterol (HDL-C) concentration is highly heritable but is also modifiable by environmental factors including physical activity. HDL-C response to exercise varies among individuals, and this variability may be associated with genetic polymorphisms in the key regulators of HDL metabolism including endothelial lipase (LIPG). We examined associations between variants LIPG T111I (rs2000813) and LIPG i24582 (rs6507931), HDL and television viewing/computer use ("screen time") as a marker for physical inactivity in a population with high prevalence of metabolic syndrome. Subjects consisted of 539 White men and 584 women (mean+/-S.D., 49+/-16 years) participating in the GOLDN study. We did not observe an association with either LIPG SNP or HDL independently of screen time. In multi-adjusted linear regression models, HDL interacted significantly with screen time as a continuous variable in LIPG i24582 subjects with TT genotype (P<0.05). By dichotomizing screen time into high and low levels, we found significant genotype-associated differences in HDL in women but not men. When screen time was >or=2.6h/day, the concentrations of total HDL-C, large HDL, large low density lipoprotein (LDL) were lower, the concentration of small LDL was higher and HDL and LDL particle sizes were smaller in subjects with LIPG i24582 TT compared to CT and CC subjects (P<0.05). We found a significant gene-physical inactivity interaction for HDL and some LDL measures for the LIPG i24582 polymorphism. Higher levels of physical activity may be protective for HDL-C concentrations and low activity detrimental in LIPG i24582 TT individuals, especially in women.

Conceptual size in developmental dyscalculia and dyslexia.

PubMed

Gliksman, Yarden; Henik, Avishai

2018-02-01

People suffering from developmental dyscalculia (DD) are known to have impairment in numerical abilities and have been found to have weaker processing of countable magnitudes. However, not much research was done on their abilities to process noncountable magnitudes. An example of noncountable magnitude is conceptual size (e.g., mouse is small and elephant is big). Recently, we found that adults process conceptual size automatically. The current study examined automatic processing of conceptual size in students with DD and developmental dyslexia. Conceptual and physical sizes were manipulated orthogonally to create congruent (e.g., a physically small apple compared to a physically large violin) and incongruent (e.g., a physically large apple compared to a physically small violin) conditions. Participants were presented with 2 objects and had to choose the larger one. Each trial began with an instruction to respond to the physical or to the conceptual dimension. Control and the dyslexic groups presented automatic processing of both conceptual and physical sizes. The dyscalculic group presented automatic processing of physical size but not automaticity of processing conceptual size. Our results fit with previous findings of weaker magnitude representation in those with DD, specifically regarding noncountable magnitudes, and support theories of a shared neurocognitive substrate for different types of magnitudes. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Does Habitual Physical Activity Increase the Sensitivity of the Appetite Control System? A Systematic Review.

PubMed

Beaulieu, Kristine; Hopkins, Mark; Blundell, John; Finlayson, Graham

2016-12-01

It has been proposed that habitual physical activity improves appetite control; however, the evidence has never been systematically reviewed. To examine whether appetite control (e.g. subjective appetite, appetite-related peptides, food intake) differs according to levels of physical activity. Medline, Embase and SPORTDiscus were searched for articles published between 1996 and 2015, using keywords pertaining to physical activity, appetite, food intake and appetite-related peptides. Articles were included if they involved healthy non-smoking adults (aged 18-64 years) participating in cross-sectional studies examining appetite control in active and inactive individuals; or before and after exercise training in previously inactive individuals. Of 77 full-text articles assessed, 28 studies (14 cross-sectional; 14 exercise training) met the inclusion criteria. Appetite sensations and absolute energy intake did not differ consistently across studies. Active individuals had a greater ability to compensate for high-energy preloads through reductions in energy intake, in comparison with inactive controls. When physical activity level was graded across cross-sectional studies (low, medium, high, very high), a significant curvilinear effect on energy intake (z-scores) was observed. Methodological issues existed concerning the small number of studies, lack of objective quantification of food intake, and various definitions used to define active and inactive individuals. Habitually active individuals showed improved compensation for the energy density of foods, but no consistent differences in appetite or absolute energy intake, in comparison with inactive individuals. This review supports a J-shaped relationship between physical activity level and energy intake. Further studies are required to confirm these findings. CRD42015019696.

Simulation experience enhances physical therapist student confidence in managing a patient in the critical care environment.

PubMed

Ohtake, Patricia J; Lazarus, Marcilene; Schillo, Rebecca; Rosen, Michael

2013-02-01

Rehabilitation of patients in critical care environments improves functional outcomes. This finding has led to increased implementation of intensive care unit (ICU) rehabilitation programs, including early mobility, and an associated increased demand for physical therapists practicing in ICUs. Unfortunately, many physical therapists report being inadequately prepared to work in this high-risk environment. Simulation provides focused, deliberate practice in safe, controlled learning environments and may be a method to initiate academic preparation of physical therapists for ICU practice. The purpose of this study was to examine the effect of participation in simulation-based management of a patient with critical illness in an ICU setting on levels of confidence and satisfaction in physical therapist students. A one-group, pretest-posttest, quasi-experimental design was used. Physical therapist students (N=43) participated in a critical care simulation experience requiring technical (assessing bed mobility and pulmonary status), behavioral (patient and interprofessional communication), and cognitive (recognizing a patient status change and initiating appropriate responses) skill performance. Student confidence and satisfaction were surveyed before and after the simulation experience. Students' confidence in their technical, behavioral, and cognitive skill performance increased from "somewhat confident" to "confident" following the critical care simulation experience. Student satisfaction was highly positive, with strong agreement the simulation experience was valuable, reinforced course content, and was a useful educational tool. Limitations of the study were the small sample from one university and a control group was not included. Incorporating a simulated, interprofessional critical care experience into a required clinical course improved physical therapist student confidence in technical, behavioral, and cognitive performance measures and was associated with high student satisfaction. Using simulation, students were introduced to the critical care environment, which may increase interest in working in this practice area.

Intrepid: Exploring the NEA population with a Fleet of Highly Autonomous SmallSat explorers

NASA Astrophysics Data System (ADS)

Blacksberg, Jordana; Chesley, Steven R.; Ehlmann, Bethany; Raymond, Carol Anne

2017-10-01

The Intrepid mission concept calls for phased deployment of a fleet of small highly autonomous rendezvous spacecraft designed to characterize the evolution, structure and composition of dozens of Near-Earth Asteroids (NEAs). Intrepid represents a marked departure from conventional solar system exploration projects, where a single unique and complex spacecraft is typically directed to explore a single target body. In contrast, Intrepid relies on the deployment of a large number of autonomous spacecraft to provide redundancy and ensure that the project goals are achieved at a small fraction of the cost of typical missions.The Intrepid science goals are threefold: (1) to understand the evolutionary processes that govern asteroid physical, chemical and dynamical histories and relate these results to solar system origins and evolution; (2) to facilitate impactor deflection scenarios for planetary defense by statistically characterizing relevant asteroid physical properties; (3) to quantify the presence and extractability of potentially useful resources on a large sample of asteroids. To achieve these goals, the baseline architecture includes multiple modular instruments including cameras, spectrometers, radar sounders, and projectiles that could interact with the target asteroid. Key questions to be addressed are: what is the total quantity of water in each object? How is the water incorporated? Are organics present? What is the asteroid physical structure? How would the object respond to impact/deflection?We have begun development of a miniature infrared point spectrometer, a cornerstone of the Intrepid payload, covering both shortwave infrared (SWIR) and mid-infrared (MIR) spectral bands. The spectrometer is designed with a compact 2U form-factor, making it both relevant to Intrepid and implementable on a CubeSat. The combination of SWIR and MIR in a single integrated instrument would enable robust compositional interpretations from a single dataset combining both solar reflectance and thermal emission spectroscopy. These measurements would be crucial to determining the quantity and nature of water present.

Hydrate morphology: Physical properties of sands with patchy hydrate saturation

USGS Publications Warehouse

Dai, S.; Santamarina, J.C.; Waite, William F.; Kneafsey, T.J.

2012-01-01

The physical properties of gas hydrate-bearing sediments depend on the volume fraction and spatial distribution of the hydrate phase. The host sediment grain size and the state of effective stress determine the hydrate morphology in sediments; this information can be used to significantly constrain estimates of the physical properties of hydrate-bearing sediments, including the coarse-grained sands subjected to high effective stress that are of interest as potential energy resources. Reported data and physical analyses suggest hydrate-bearing sands contain a heterogeneous, patchy hydrate distribution, whereby zones with 100% pore-space hydrate saturation are embedded in hydrate-free sand. Accounting for patchy rather than homogeneous hydrate distribution yields more tightly constrained estimates of physical properties in hydrate-bearing sands and captures observed physical-property dependencies on hydrate saturation. For example, numerical modeling results of sands with patchy saturation agree with experimental observation, showing a transition in stiffness starting near the series bound at low hydrate saturations but moving toward the parallel bound at high hydrate saturations. The hydrate-patch size itself impacts the physical properties of hydrate-bearing sediments; for example, at constant hydrate saturation, we find that conductivity (electrical, hydraulic and thermal) increases as the number of hydrate-saturated patches increases. This increase reflects the larger number of conductive flow paths that exist in specimens with many small hydrate-saturated patches in comparison to specimens in which a few large hydrate saturated patches can block flow over a significant cross-section of the specimen.

Comet 209P/LINEAR's Very Close Approach to Earth: Probing the Inner-Coma Physical Environment and Volatile Composition

NASA Astrophysics Data System (ADS)

Bonev, Boncho P.; DiSanti, Michael; Mumma, Michael; Gibb, Erika; Villanueva, Geronimo; Paganini, Lucas; Combi, Michael; Magee-Sauer, Karen

2014-02-01

Using NIRSPEC at Keck 2 we propose spatially-resolved high- resolution spectroscopic observations of H_2O emission in the coma of the Jupiter-family comet 209P/LINEAR. The exceptionally small geocentric distance - 0.06 AU - will afford very high spatial resolution. Using long-slit spectroscopy we will measure the spatial variation of the temperature and column density of water, providing a very rare direct quantitative view of the physical state in the innermost region of a cometary atmosphere, within 50-100 km from the nucleus. To maximize the science return, we will also measure the abundances of CH_3OH and C_2H_6 simultaneously with H_2O. Only one instrument setting is required for our entire investigation, thereby optimizing observing efficiency. Our proposed study targets improved understanding of the near-nucleus coma physics, and of the primary volatile composition of Jupiter-family comets, a dynamical group which remains underrepresented in modern taxonomical studies. In addition, this project will provide a context for interpreting results from the Rosetta mission, and also a test of state-of-the-art physical models of the coma.

Comparison of technical and physical activities between 8 vs. 8 and 11 vs. 11 games in young Korean soccer players

PubMed Central

Oh, Seong Hwan; Joo, Chang Hwa

2018-01-01

The aims of this study were to examine the differences in technical aspects and physical demands between small-size games (SSG; 8 vs. 8) and regular-size games (RSG; 11 vs. 11) in young Korean soccer players. Seventy-nine young soccer players from 6 teams (U-12) volunteered to participate in the study. The players completed 4 games (2 SSG, 62×51 m, and 2 RSG, 80×54 m) in 2 days. Each game was filmed to evaluate technical actions. Physical demand variables were measured using global positioning system technology. SSG showed significantly greater numbers of technical plays among 17 variables when compared to RSG (P<0.05). The players covered significantly greater total distance during low−, moderate−, and high-speed running and sprinting in SSG than in RSG (P<0.05). Higher numbers of high-intensity activities (repeated high-intensity efforts, explosive efforts, decelera-tions, accelerations, and sprinting) were observed in SSG compared to RSG (P<0.05). Mean heart rate was also higher in SSG than in RSG (P<0.05). Despite the greater physical demands during SSG, the exercise intensity was similar to that reported in previous studies. Therefore, the SSG format applied in the present study can be a suitable official game format for Korean young soccer players, resulting in significantly greater exposure to technical plays without excessive physical demands. PMID:29740560

Small Schools Curriculum: Physical Education, 7-12.

ERIC Educational Resources Information Center

Hartl, David, Ed.; Hartl, Doris, Ed.

Two self-contained sections within the document (one for grades 7-8, the other for grades 9-12) present the Washington Small Schools secondary physical education curriculum. Activities are written to supplement or extend a basic text by presenting a game, simulation or activity to carry out a learning objective. Identical introductory materials…

Physical Education for Individuals with Disabilities in Washington State's Rural School Districts.

ERIC Educational Resources Information Center

Palma, Gloria M.

This study investigated the nature and extent of physical education programs for individuals with disabilities in Washington State's small rural public school districts. Questionnaires were sent to 185 superintendents of small rural school districts in the state. Of the 128 responses, 70.3% enrolled individuals with disabilities. Fifty-eight…

Simulation of Ultra-Small MOSFETs Using a 2-D Quantum-Corrected Drift-Diffusion Model

NASA Technical Reports Server (NTRS)

Biegal, Bryan A.; Rafferty, Connor S.; Yu, Zhiping; Ancona, Mario G.; Dutton, Robert W.; Saini, Subhash (Technical Monitor)

1998-01-01

The continued down-scaling of electronic devices, in particular the commercially dominant MOSFET, will force a fundamental change in the process of new electronics technology development in the next five to ten years. The cost of developing new technology generations is soaring along with the price of new fabrication facilities, even as competitive pressure intensifies to bring this new technology to market faster than ever before. To reduce cost and time to market, device simulation must become a more fundamental, indeed dominant, part of the technology development cycle. In order to produce these benefits, simulation accuracy must improve markedly. At the same time, device physics will become more complex, with the rapid increase in various small-geometry and quantum effects. This work describes both an approach to device simulator development and a physical model which advance the effort to meet the tremendous electronic device simulation challenge described above. The device simulation approach is to specify the physical model at a high level to a general-purpose (but highly efficient) partial differential equation solver (in this case PROPHET, developed by Lucent Technologies), which then simulates the model in 1-D, 2-D, or 3-D for a specified device and test regime. This approach allows for the rapid investigation of a wide range of device models and effects, which is certainly essential for device simulation to catch up with, and then stay ahead of, electronic device technology of the present and future. The physical device model used in this work is the density-gradient (DG) quantum correction to the drift-diffusion model [Ancona, Phys. Rev. B 35(5), 7959 (1987)]. This model adds tunneling and quantum smoothing of carrier density profiles to the drift-diffusion model. We used the DG model in 1-D and 2-D (for the first time) to simulate both bipolar and unipolar devices. Simulations of heavily-doped, short-base diodes indicated that the DG quantum corrections do not have a large effect on the IN characteristics of electronic devices without heteroj unction s. On the other hand, ultra-small MOSFETs certainly exhibit important quantum effects that the DG model will include: quantum repulsion of the inversion and gate charges from the oxide interfaces, and quantum tunneling through thin gate oxides. We present initial results of 2-D DG simulations of ultra-small MOSFETs. Subtle but important issues involving the specification of the model, boundary conditions, and interface constraints for DG simulation of MOSFETs will also be illuminated.

Learning Physics-based Models in Hydrology under the Framework of Generative Adversarial Networks

NASA Astrophysics Data System (ADS)

Karpatne, A.; Kumar, V.

2017-12-01

Generative adversarial networks (GANs), that have been highly successful in a number of applications involving large volumes of labeled and unlabeled data such as computer vision, offer huge potential for modeling the dynamics of physical processes that have been traditionally studied using simulations of physics-based models. While conventional physics-based models use labeled samples of input/output variables for model calibration (estimating the right parametric forms of relationships between variables) or data assimilation (identifying the most likely sequence of system states in dynamical systems), there is a greater opportunity to explore the full power of machine learning (ML) methods (e.g, GANs) for studying physical processes currently suffering from large knowledge gaps, e.g. ground-water flow. However, success in this endeavor requires a principled way of combining the strengths of ML methods with physics-based numerical models that are founded on a wealth of scientific knowledge. This is especially important in scientific domains like hydrology where the number of data samples is small (relative to Internet-scale applications such as image recognition where machine learning methods has found great success), and the physical relationships are complex (high-dimensional) and non-stationary. We will present a series of methods for guiding the learning of GANs using physics-based models, e.g., by using the outputs of physics-based models as input data to the generator-learner framework, and by using physics-based models as generators trained using validation data in the adversarial learning framework. These methods are being developed under the broad paradigm of theory-guided data science that we are developing to integrate scientific knowledge with data science methods for accelerating scientific discovery.

Physical activity, sedentary behavior and their correlates in children with Autism Spectrum Disorder: A systematic review

PubMed Central

Downing, Katherine; Rinehart, Nicole J.; Barnett, Lisa M.; May, Tamara; McGillivray, Jane A.; Papadopoulos, Nicole V.; Skouteris, Helen; Timperio, Anna

2017-01-01

Autism Spectrum Disorder affects up to 2.5% of children and is associated with harmful health outcomes (e.g. obesity). Low levels of physical activity and high levels of sedentary behaviors may contribute to harmful health outcomes. To systematically review the prevalence and correlates of physical activity and sedentary behaviors in children with Autism Spectrum Disorder, electronic databases (PsycINFO, SPORTDiscus, EMBASE, Medline) were searched from inception to November 2015. The review was registered with PROSPERO (CRD42014013849). Peer-reviewed, English language studies were included. Two reviewers screened potentially relevant articles. Outcomes of interest were physical activity and sedentary behaviour levels and their potential correlates. Data were collected and analysed in 2015. Of 35 included studies, 15 reported physical activity prevalence, 10 reported physical activity correlates, 18 reported sedentary behavior prevalence, and 10 reported sedentary behavior correlates. Estimates of children’s physical activity (34–166 mins/day, average 86 mins/day) and sedentary behavior (126–558 mins/day in screen time, average 271 mins/day; 428–750 mins/day in total sedentary behavior, average 479 mins/day) varied across studies. Age was consistently inversely associated, and sex inconsistently associated with physical activity. Age and sex were inconsistently associated with sedentary behavior. Sample sizes were small. All but one of the studies were classified as having high risk of bias. Few correlates have been reported in sufficient studies to provide overall estimates of associations. Potential correlates in the physical environment remain largely unexamined. This review highlights varying levels of physical activity and sedentary behavior in children with Autism Spectrum Disorder. Research is needed to consistently identify the correlates of these behaviors. There is a critical need for interventions to support healthy levels of these behaviors. PMID:28245224

AMS Radiocarbon Dating Individual Taxa and Individual Specimens: Implications for Small Mammal Paleoecology.

NASA Astrophysics Data System (ADS)

Graham, Russell; Stafford, Thomas, Jr.; Semken, Holmes, Jr.

2010-05-01

Advances in AMS physics and organic geochemistry have revolutionized our ability to establish absolute chronologies on vertebrate fossils. Highly purified collagen, which provides extremely accurate 14C ages, can be extracted from single bones and teeth as small as 50 mg. Combined with measurement precisions of ±15 to 25 years for ages of < 20,000 yr, the direct AMS 14C technique enables fossil deposits to be chronologically dissected at the level of single animals. Analysis of data from a variety of sites in the United States indicates that most excavation levels (analysis units) as small as 10 cm can be time averaged by several thousand years at a minimum, even with the greatest care in excavation and processing of sediments. Time averaging of this magnitude has important implications for fine-scale paleoecological analysis of faunas, especially when compared to high-resolution climate records like those derived from speleothems, ice cores, or marine cores. To this end, we propose saturation dating of indicative taxa and plotting dates of individual specimens against high-resolution climate records rather than analysis of complete faunas or faunules. This technique provides even higher resolution of paleoenvironments than pollen spectra.

Distant Comets in the Early Solar System

NASA Technical Reports Server (NTRS)

Meech, Karen J.

2000-01-01

The main goal of this project is to physically characterize the small outer solar system bodies. An understanding of the dynamics and physical properties of the outer solar system small bodies is currently one of planetary science's highest priorities. The measurement of the size distributions of these bodies will help constrain the early mass of the outer solar system as well as lead to an understanding of the collisional and accretional processes. A study of the physical properties of the small outer solar system bodies in comparison with comets in the inner solar system and in the Kuiper Belt will give us information about the nebular volatile distribution and small body surface processing. We will increase the database of comet nucleus sizes making it statistically meaningful (for both Short-Period and Centaur comets) to compare with those of the Trans-Neptunian Objects. In addition, we are proposing to do active ground-based observations in preparation for several upcoming space missions.

Developing the learning physical science curriculum: Adapting a small enrollment, laboratory and discussion based physical science course for large enrollments

NASA Astrophysics Data System (ADS)

Goldberg, Fred; Price, Edward; Robinson, Stephen; Boyd-Harlow, Danielle; McKean, Michael

2012-06-01

We report on the adaptation of the small enrollment, lab and discussion based physical science course, Physical Science and Everyday Thinking (PSET), for a large-enrollment, lecture-style setting. Like PSET, the new Learning Physical Science (LEPS) curriculum was designed around specific principles based on research on learning to meet the needs of nonscience students, especially prospective and practicing elementary and middle school teachers. We describe the structure of the two curricula and the adaptation process, including a detailed comparison of similar activities from the two curricula and a case study of a LEPS classroom implementation. In LEPS, short instructor-guided lessons replace lengthier small group activities, and movies, rather than hands-on investigations, provide the evidence used to support and test ideas. LEPS promotes student peer interaction as an important part of sense making via “clicker” questions, rather than small group and whole class discussions typical of PSET. Examples of student dialog indicate that this format is capable of generating substantive student discussion and successfully enacting the design principles. Field-test data show similar student content learning gains with the two curricula. Nevertheless, because of classroom constraints, some important practices of science that were an integral part of PSET were not included in LEPS.

Plasma Physics Challenges of MM-to-THz and High Power Microwave Generation

NASA Astrophysics Data System (ADS)

Booske, John

2007-11-01

Homeland security and military defense technology considerations have stimulated intense interest in mobile, high power sources of millimeter-wave to terahertz regime electromagnetic radiation, from 0.1 to 10 THz. While sources at the low frequency end, i.e., the gyrotron, have been deployed or are being tested for diverse applications such as WARLOC radar and active denial systems, the challenges for higher frequency sources have yet to be completely met for applications including noninvasive sensing of concealed weapons and dangerous agents, high-data-rate communications, and high resolution spectroscopy and atmospheric sensing. The compact size requirements for many of these high frequency sources requires miniscule, micro-fabricated slow wave circuits with high rf ohmic losses. This necessitates electron beams with not only very small transverse dimensions but also very high current density for adequate gain. Thus, the emerging family of mm-to-THz e-beam-driven vacuum electronics devices share many of the same plasma physics challenges that currently confront ``classic'' high power microwave (HPM) generators [1] including bright electron sources, intense beam transport, energetic electron interaction with surfaces and rf air breakdown at output windows. Multidimensional theoretical and computational models are especially important for understanding and addressing these challenges. The contemporary plasma physics issues, recent achievements, as well as the opportunities and outlook on THz and HPM will be addressed. [1] R.J. Barker, J.H. Booske, N.C. Luhmann, and G.S. Nusinovich, Modern Microwave and Millimeter-Wave Power Electronics (IEEE/Wiley, 2005).

Regional Community Climate Simulations with variable resolution meshes in the Community Earth System Model

NASA Astrophysics Data System (ADS)

Zarzycki, C. M.; Gettelman, A.; Callaghan, P.

2017-12-01

Accurately predicting weather extremes such as precipitation (floods and droughts) and temperature (heat waves) requires high resolution to resolve mesoscale dynamics and topography at horizontal scales of 10-30km. Simulating such resolutions globally for climate scales (years to decades) remains computationally impractical. Simulating only a small region of the planet is more tractable at these scales for climate applications. This work describes global simulations using variable-resolution static meshes with multiple dynamical cores that target the continental United States using developmental versions of the Community Earth System Model version 2 (CESM2). CESM2 is tested in idealized, aquaplanet and full physics configurations to evaluate variable mesh simulations against uniform high and uniform low resolution simulations at resolutions down to 15km. Different physical parameterization suites are also evaluated to gauge their sensitivity to resolution. Idealized variable-resolution mesh cases compare well to high resolution tests. More recent versions of the atmospheric physics, including cloud schemes for CESM2, are more stable with respect to changes in horizontal resolution. Most of the sensitivity is due to sensitivity to timestep and interactions between deep convection and large scale condensation, expected from the closure methods. The resulting full physics model produces a comparable climate to the global low resolution mesh and similar high frequency statistics in the high resolution region. Some biases are reduced (orographic precipitation in the western United States), but biases do not necessarily go away at high resolution (e.g. summertime JJA surface Temp). The simulations are able to reproduce uniform high resolution results, making them an effective tool for regional climate studies and are available in CESM2.

Accelerometer-measured sedentary behaviour and physical activity of inpatients with severe mental illness.

PubMed

Kruisdijk, Frank; Deenik, Jeroen; Tenback, Diederik; Tak, Erwin; Beekman, Aart-Jan; van Harten, Peter; Hopman-Rock, Marijke; Hendriksen, Ingrid

2017-08-01

Sedentary behaviour and lack of physical activity threatens health. Research concerning these behaviours of inpatients with severe mental illness is limited but urgently needed to reveal prevalence and magnitude. In total, 184 inpatients (men n =108, women n =76, mean age 57,4, 20% first generation antipsychotics, 40% second generation antipsychotics, 43% antidepressants, mean years hospitalisation 13 years), with severe mental illness of a Dutch psychiatric hospital wore an accelerometer for five days to objectively measure total activity counts per hour and percentages in sedentary behaviour, light intensity physical activity and moderate to vigorous physical activity. Accelerometer data were compared with data of 54 healthy ward employees. Patients showed significantly less activity counts per hour compared to employees (p=0.02), although the differences were small (d=0.32). Patients were sedentary during 84% of the wear time (50min/h), spend 10% in light intensity physical activity and 6% in moderate to vigorous physical activity. Age was the only significant predictor, predicting less total activity counts/h in higher ages. Decreasing sedentary behaviour and improving physical activity in this population should be a high priority in clinical practice. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Source limitation of carbon gas emissions in high-elevation mountain streams and lakes

USGS Publications Warehouse

Crawford, John T.; Dornblaser, Mark M.; Stanley, Emily H.; Clow, David W.; Striegl, Robert G.

2015-01-01

Inland waters are an important component of the global carbon cycle through transport, storage, and direct emissions of CO2 and CH4 to the atmosphere. Despite predictions of high physical gas exchange rates due to turbulent flows and ubiquitous supersaturation of CO2—and perhaps also CH4—patterns of gas emissions are essentially undocumented for high mountain ecosystems. Much like other headwater networks around the globe, we found that high-elevation streams in Rocky Mountain National Park, USA, were supersaturated with CO2 during the growing season and were net sources to the atmosphere. CO2concentrations in lakes, on the other hand, tended to be less than atmospheric equilibrium during the open water season. CO2 and CH4 emissions from the aquatic conduit were relatively small compared to many parts of the globe. Irrespective of the physical template for high gas exchange (high k), we found evidence of CO2 source limitation to mountain streams during the growing season, which limits overall CO2emissions. Our results suggest a reduced importance of aquatic ecosystems for carbon cycling in high-elevation landscapes having limited soil development and high CO2 consumption via mineral weathering.

Dust-obscured galaxies in the local universe

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hwang, Ho Seong; Geller, Margaret J., E-mail: hhwang@cfa.harvard.edu, E-mail: mgeller@cfa.harvard.edu

We use Wide-field Infrared Survey Explorer (WISE), AKARI, and Galaxy Evolution Explorer (GALEX) data to select local analogs of high-redshift (z ∼ 2) dust obscured galaxies (DOGs). We identify 47 local DOGs with S {sub 12μm}/S {sub 0.22μm} ≥ 892 and S {sub 12μm} > 20 mJy at 0.05 < z < 0.08 in the Sloan Digital Sky Survey data release 7. The infrared (IR) luminosities of these DOGs are in the range 3.4 × 10{sup 10} (L {sub ☉}) ≲ L {sub IR} ≲ 7.0 × 10{sup 11} (L {sub ☉}) with a median L {sub IR} of 2.1more » × 10{sup 11} (L {sub ☉}). We compare the physical properties of local DOGs with a control sample of galaxies that have lower S {sub 12μm}/S {sub 0.22μm} but have similar redshift, IR luminosity, and stellar mass distributions. Both WISE 12 μm and GALEX near-ultraviolet (NUV) flux densities of DOGs differ from the control sample of galaxies, but the difference is much larger in the NUV. Among the 47 DOGs, 36% ± 7% have small axis ratios in the optical (i.e., b/a < 0.6), larger than the fraction among the control sample (17% ± 3%). There is no obvious sign of interaction for many local DOGs. No local DOGs have companions with comparable optical magnitudes closer than ∼50 kpc. The large- and small-scale environments of DOGs are similar to the control sample. Many physical properties of local DOGs are similar to those of high-z DOGs, even though the IR luminosities of local objects are an order of magnitude lower than for the high-z objects: the presence of two classes (active galactic nuclei- and star formation-dominated) of DOGs, abnormal faintness in the UV rather than extreme brightness in the mid-IR, and diverse optical morphology. These results suggest a common underlying physical origin of local and high-z DOGs. Both seem to represent the high-end tail of the dust obscuration distribution resulting from various physical mechanisms rather than a unique phase of galaxy evolution.« less

Toward Computational Design of High-Efficiency Photovoltaics from First-Principles

DTIC Science & Technology

2016-08-15

dependence of exciton diffusion in conjugated small molecules, Applied Physics Letters, (04 2014): 0. doi: 10.1063/1.4871303 Guangfen Wu, Zi Li, Xu...principle approach based on the time- dependent density functional theory (TDDFT) to describe exciton states, including energy levels and many-body wave... depends more sensitively on the dimension and crystallinity of the acceptor parallel to the interface than normal to the interface. Reorganization

Commercial thinning in small-diameter aspen stands in northern Minnesota: study establishment report

Treesearch

Daniel W. Gilmore; Jennifer D. Glenn; Michael E. Ostry; John C. Zasada; Michael A. Benedict

2006-01-01

In the spring of 1999, a long-term study was established to examine the physical and biological aspects of thinning young aspen stands in Minnesota. Three aspen stands ranging in age from 25 to 35 years were selected on lands owned by the State of Minnesota and UPM Kymmene. Two thinning treatments (low and high density) and an unthinned control were installed at each...

A gene family for acidic ribosomal proteins in Schizosaccharomyces pombe: two essential and two nonessential genes.

PubMed Central

Beltrame, M; Bianchi, M E

1990-01-01

We have cloned the genes for small acidic ribosomal proteins (A-proteins) of the fission yeast Schizosaccharomyces pombe. S. pombe contains four transcribed genes for small A-proteins per haploid genome, as is the case for Saccharomyces cerevisiae. In contrast, multicellular eucaryotes contain two transcribed genes per haploid genome. The four proteins of S. pombe, besides sharing a high overall similarity, form two couples of nearly identical sequences. Their corresponding genes have a very conserved structure and are transcribed to a similar level. Surprisingly, of each couple of genes coding for nearly identical proteins, one is essential for cell growth, whereas the other is not. We suggest that the unequal importance of the four small A-proteins for cell survival is related to their physical organization in 60S ribosomal subunits. Images PMID:2325655

Nuclear data libraries assessment for modelling a small fluoride salt-cooled, high-temperature reactor

NASA Astrophysics Data System (ADS)

Mohamed, Hassan; Lindley, Benjamin; Parks, Geoffrey

2017-01-01

Nuclear data consists of measured or evaluated probabilities of various fundamental physical interactions involving the nuclei of atoms and their properties. Most fluoride salt-cooled high-temperature reactor (FHR) studies that were reviewed do not give detailed information on the data libraries used in their assessments. Therefore, the main objective of this data libraries comparison study is to investigate whether there are any significant discrepancies between main data libraries, namely ENDF/B-VII, JEFF-3.1 and JEF-2.2. Knowing the discrepancies, especially its magnitude, is important and relevant for readers as to whether further cautions are necessary for any future verification or validation processes when modelling an FHR. The study is performed using AMEC's reactor physics software tool, WIMS. The WIMS calculation is simply a 2-D infinite lattice of fuel assembly calculation. The comparison between the data libraries in terms of infinite multiplication factor, kinf and pin power map are presented. Results show that the discrepancy between JEFF-3.1 and ENDF/B-VII libraries is reasonably small but increases as the fuel depletes due to the data libraries uncertainties that are accumulated at each burnup step. Additionally, there are large discrepancies between JEF-2.2 and ENDF/B-VII because of the inadequacy of the JEF-2.2 library.

Ultra-small plutonium oxide nanocrystals: an innovative material in plutonium science.

PubMed

Hudry, Damien; Apostolidis, Christos; Walter, Olaf; Janssen, Arne; Manara, Dario; Griveau, Jean-Christophe; Colineau, Eric; Vitova, Tonya; Prüssmann, Tim; Wang, Di; Kübel, Christian; Meyer, Daniel

2014-08-11

Apart from its technological importance, plutonium (Pu) is also one of the most intriguing elements because of its non-conventional physical properties and fascinating chemistry. Those fundamental aspects are particularly interesting when dealing with the challenging study of plutonium-based nanomaterials. Here we show that ultra-small (3.2±0.9 nm) and highly crystalline plutonium oxide (PuO2 ) nanocrystals (NCs) can be synthesized by the thermal decomposition of plutonyl nitrate ([PuO2 (NO3 )2 ]⋅3 H2 O) in a highly coordinating organic medium. This is the first example reporting on the preparation of significant quantities (several tens of milligrams) of PuO2 NCs, in a controllable and reproducible manner. The structure and magnetic properties of PuO2 NCs have been characterized by a wide variety of techniques (powder X-ray diffraction (PXRD), X-ray absorption fine structure (XAFS), X-ray absorption near edge structure (XANES), TEM, IR, Raman, UV/Vis spectroscopies, and superconducting quantum interference device (SQUID) magnetometry). The current PuO2 NCs constitute an innovative material for the study of challenging problems as diverse as the transport behavior of plutonium in the environment or size and shape effects on the physics of transuranium elements. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

PHYSICAL CHARACTERIZATION OF ∼2 m DIAMETER NEAR-EARTH ASTEROID 2015 TC25: A POSSIBLE BOULDER FROM E-TYPE ASTEROID (44) NYSA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reddy, Vishnu; Sanchez, Juan A.; Bottke, William F.

Small near-Earth asteroids (NEAs) (<20 m) are interesting, because they are progenitors for meteorites in our terrestrial collection. The physical characteristics of these small NEAs are crucial to our understanding of the effectiveness of our atmosphere in filtering low-strength impactors. In the past, the characterization of small NEAs has been a challenge, because of the difficulty in detecting them prior to close Earth flyby. In this study, we physically characterized the 2 m diameter NEA 2015 TC25 using ground-based optical, near-infrared and radar assets during a close flyby of the Earth (distance 128,000 km) in 2015 October 12. Our observationsmore » suggest that its surface composition is similar to aubrites, a rare class of high-albedo differentiated meteorites. Aubrites make up only 0.14% of all known meteorites in our terrestrial meteorite collection. 2015 TC25 is also a very fast rotator with a period of 133 ± 6 s. We combined the spectral and dynamical properties of 2015 TC25 and found the best candidate source body in the inner main belt to be the 70 km diameter E-type asteroid (44) Nysa. We attribute the difference in spectral slope between the two objects to the lack of regolith on the surface of 2015 TC25. Using the albedo of E-type asteroids (50%–60%) we refine the diameter of 2015 TC25 to 2 m, making it one of the smallest NEAs ever to be characterized.« less

Comparing Two Cooperative Small Group Formats Used with Physical Therapy and Medical Students

ERIC Educational Resources Information Center

D'Eon, Marcel; Proctor, Peggy; Reeder, Bruce

2007-01-01

This study compared "Structured Controversy" (a semi-formal debate like small group activity) with a traditional open discussion format for medical and physical therapy students. We found that those students who had participated in Structured Controversy changed their personal opinion on the topic more than those who were in the Open Discussion…

The physics of small megavoltage photon beam dosimetry.

PubMed

Andreo, Pedro

2018-02-01

The increased interest during recent years in the use of small megavoltage photon beams in advanced radiotherapy techniques has led to the development of dosimetry recommendations by different national and international organizations. Their requirement of data suitable for the different clinical options available, regarding treatment units and dosimetry equipment, has generated a considerable amount of research by the scientific community during the last decade. The multiple publications in the field have led not only to the availability of new invaluable data, but have also contributed substantially to an improved understanding of the physics of their dosimetry. This work provides an overview of the most important aspects that govern the physics of small megavoltage photon beam dosimetry. Copyright © 2017 Elsevier B.V. All rights reserved.

Patterns of physical activity in children with haemophilia.

PubMed

Broderick, C R; Herbert, R D; Latimer, J; van Doorn, N

2013-01-01

The current widespread use of prophylaxis in developed countries has enabled greater participation in physical activity. However, there are no data available on leisure-time physical activity in Australian children with haemophilia. The data reported here were obtained from a case-crossover study nested in a prospective cohort study of 104 boys with moderate and severe haemophilia followed for one year. Each child's physical activity was assessed using a modifiable physical activity questionnaire (Kriska's MAQ) administered at baseline, and a one-week prospective activity diary at a randomly determined time. Children were aged 4-18 years. The median time spent in sport or leisure-time physical activity in the preceding year was 7.9 h/week (IQR 4.6 to 12.9). The median time spent in vigorous physical activity was 3.8 h/week (IQR 1.6 to 6.4) and in moderate and vigorous physical activity 6.4 h/week (IQR 3.7 to 10.0). The median small-screen time was 2.5 h/day (IQR 0.5 to 2.5). Forty-five per cent of all children and 61% of children over the age of 10 years played at least one competitive sport. Averaged across one week, 43% of all children met the Australian government physical activity guidelines for children and 36% met the guidelines for small-screen time. This study provides the first data regarding leisure-time physical activity in children with haemophilia living in Australia. The majority of Australian children with haemophilia are not meeting the national physical activity and small-screen time guidelines. © 2012 Blackwell Publishing Ltd.

Hadron collider tests of neutrino mass-generating mechanisms

NASA Astrophysics Data System (ADS)

Ruiz, Richard Efrain

The Standard Model of particle physics (SM) is presently the best description of nature at small distances and high energies. However, with tiny but nonzero neutrino masses, a Higgs boson mass unstable under radiative corrections, and little guidance on understanding the hierarchy of fermion masses, the SM remains an unsatisfactory description of nature. Well-motivated scenarios that resolve these issues exist but also predict extended gauge (e.g., Left-Right Symmetric Models), scalar (e.g., Supersymmetry), and/or fermion sectors (e.g., Seesaw Models). Hence, discovering such new states would have far-reaching implications. After reviewing basic tenets of the SM and collider physics, several beyond the SM (BSM) scenarios that alleviate these shortcomings are investigated. Emphasis is placed on the production of a heavy Majorana neutrinos at hadron colliders in the context of low-energy, effective theories that simultaneously explain the origin of neutrino masses and their smallness compared to other elementary fermions, the so-called Seesaw Mechanisms. As probes of new physics, rare top quark decays to Higgs bosons in the context of the SM, the Types I and II Two Higgs Doublet Model (2HDM), and the semi-model independent framework of Effective Field Theory (EFT) have also been investigated. Observation prospects and discovery potentials of these models at current and future collider experiments are quantified.

Can Applied Naturoptics Fund Associates Degrees in Applied Optics Graduates, in the Americas and Elsewhere, into BS/MS/PhD Physics/Applied Physics Programs?

NASA Astrophysics Data System (ADS)

Ferreira, Nadja; Andrade, Jennifer; Mc Leod, Roger D.

2007-04-01

Youthful females and other disadvantaged minority members sometimes develop visual handicaps when educational and/or other stressors are present. Special methods already available, effective, and underutilized, can be marshaled towards correcting current technologic and academic systems demand-supply mismatches in the sciences. More efficient harvesting of intellectually advantaged youthful students may represent more-highly-productive global scientific output. RDM has found that it is possible to motivate, stimulate, teach, and foster increased science interest by interacting with students at the earliest possible academic moments. The same applied optics of burning paper with a magnifying glass, and prismatic dispersing of light, allows understanding how vision operates, and can be damaged. Providing information to all students that they safely can self-repair damaged vision could only increase their interest in physics and special work-study programs. ``Indians'' are the most poorly represented group at all levels of education and its support services. MOLLOCKET/MULLAH indicates extra-human/higher-power interactions. Why? Obvious survival value suggests possible information-transmission attempts like those accessed by ``Indians.'' To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.C2.2

Who is the competent physics student? A study of students' positions and social interaction in small-group discussions

NASA Astrophysics Data System (ADS)

Due, Karin

2014-06-01

This article describes a study which explored the social interaction and the reproduction and challenge of gendered discourses in small group discussions in physics. Data for the study consisted of video recordings of eight upper secondary school groups solving physics problems and 15 audiotaped individual interviews with participating students. The analysis was based on gender theory viewing gender both as a process and a discourse. Specifically discursive psychology analysis was used to examine how students position themselves and their peers within discourses of physics and gender. The results of the study reveal how images of physics and of "skilled physics student" were constructed in the context of the interviews. These discourses were reconstructed in the students' discussions and their social interactions within groups. Traditional gendered positions were reconstructed, for example with boys positioned as more competent in physics than girls. These positions were however also resisted and challenged.

Physical Activity and Metabolic Syndrome among Ethiopian Adults

PubMed Central

2013-01-01

BACKGROUND The global prevalence of chronic noncommunicable diseases (NCDs) is on the rise, with the majority of the growth occurring among populations in developing countries. Few studies have quantified the health benefits for physical activity among sub-Saharan African adults. We examined associations of physical activity with the prevalence of metabolic syndrome (MetS) and its components in Ethiopian men and women. METHODS This cross-sectional study of 1,843 individuals (1,117 men and 726 women) was conducted among working adults (public schools and bank employees) in Addis Ababa, Ethiopia. The study was conducted in accordance with the STEPwise approach of the World Health Organization. Physical activity was assessed using a previously validated Global Physical Activity Questionnaire. MetS was defined according to the International Diabetes Federation criteria. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI). RESULTS The odds of MetS was inversely associated with physical activity in men (P trend = 0.02) but not women (P trend = 0.85). Among men, the OR of MetS comparing those with high vs. low levels of physical activity was 0.56 (95% CI = 0.33–0.97). For women, the corresponding OR was 1.07 (95% CI = 0.57–2.01). Physical activity was significantly and inversely associated with high waist circumference and hypertriglyceridemia among men, but no such associations were observed among women. CONCLUSIONS Higher levels of physical activity were inversely associated with MetS and several individual components among men. No similar trends were observed among women in this cohort, in part because of the small sample size. PMID:23422933

A ``Cyber Wind Facility'' for HPC Wind Turbine Field Experiments

NASA Astrophysics Data System (ADS)

Brasseur, James; Paterson, Eric; Schmitz, Sven; Campbell, Robert; Vijayakumar, Ganesh; Lavely, Adam; Jayaraman, Balaji; Nandi, Tarak; Jha, Pankaj; Dunbar, Alex; Motta-Mena, Javier; Craven, Brent; Haupt, Sue

2013-03-01

The Penn State ``Cyber Wind Facility'' (CWF) is a high-fidelity multi-scale high performance computing (HPC) environment in which ``cyber field experiments'' are designed and ``cyber data'' collected from wind turbines operating within the atmospheric boundary layer (ABL) environment. Conceptually the ``facility'' is akin to a high-tech wind tunnel with controlled physical environment, but unlike a wind tunnel it replicates commercial-scale wind turbines operating in the field and forced by true atmospheric turbulence with controlled stability state. The CWF is created from state-of-the-art high-accuracy technology geometry and grid design and numerical methods, and with high-resolution simulation strategies that blend unsteady RANS near the surface with high fidelity large-eddy simulation (LES) in separated boundary layer, blade and rotor wake regions, embedded within high-resolution LES of the ABL. CWF experiments complement physical field facility experiments that can capture wider ranges of meteorological events, but with minimal control over the environment and with very small numbers of sensors at low spatial resolution. I shall report on the first CWF experiments aimed at dynamical interactions between ABL turbulence and space-time wind turbine loadings. Supported by DOE and NSF.

The hydrodynamic principle for the caudal fin shape of small aquatic animals

NASA Astrophysics Data System (ADS)

Lee, Jeongsu; Park, Yong-Jai; Cho, Kyu-Jin; Kim, Ho-Young

2014-11-01

The shape of caudal fins of small aquatic animals is completely different from that of large cruising animals like dolphin and tuna which have high aspect-ratio lunate tail. To unveil the physical principle behind natural selection of caudal fins of small aquatic animals, here we investigate the hydrodynamics of an angularly reciprocating plate as a model for the caudal fin oscillation. We find that the thrust production of a reciprocating plate at high Strouhal numbers is dominated by generation of two distinct vortical structures associated with the acceleration and deceleration of the plate regardless of their shape. Based on our observations, we construct a scaling law to predict the thrust of the flapping plate, which agrees well with the experimental data. We then seek the optimal aspect ratio to maximize thrust and efficiency of a flapping plate for fixed flapping frequency and amplitude. Thrust is maximized for the aspect ratio of approximately 0.7. We also theoretically explain the power law behaviors of the thrust and efficiency as a function of the aspect ratio.

An energy balance climate model with cloud feedbacks

NASA Technical Reports Server (NTRS)

Roads, J. O.; Vallis, G. K.

1984-01-01

The present two-level global climate model, which is based on the atmosphere-surface energy balance, includes physically based parameterizations for the exchange of heat and moisture across latitude belts and between the surface and the atmosphere, precipitation and cloud formation, and solar and IR radiation. The model field predictions obtained encompass surface and atmospheric temperature, precipitation, relative humidity, and cloudiness. In the model integrations presented, it is noted that cloudiness is generally constant with changing temperature at low latitudes. High altitude cloudiness increases with temperature, although the cloud feedback effect on the radiation field remains small because of compensating effects on thermal and solar radiation. The net global feedback by the cloud field is negative, but small.

Spherical torus fusion reactor

DOEpatents

Peng, Yueng-Kay M.

1989-04-04

A fusion reactor is provided having a near spherical-shaped plasma with a modest central opening through which straight segments of toroidal field coils extend that carry electrical current for generating a toroidal magnet plasma confinement fields. By retaining only the indispensable components inboard of the plasma torus, principally the cooled toroidal field conductors and in some cases a vacuum containment vessel wall, the fusion reactor features an exceptionally small aspect ratio (typically about 1.5), a naturally elongated plasma cross section without extensive field shaping, requires low strength magnetic containment fields, small size and high beta. These features combine to produce a spherical torus plasma in a unique physics regime which permits compact fusion at low field and modest cost.

Spherical torus fusion reactor

DOEpatents

Peng, Yueng-Kay M.

1989-01-01

A fusion reactor is provided having a near spherical-shaped plasma with a modest central opening through which straight segments of toroidal field coils extend that carry electrical current for generating a toroidal magnet plasma confinement fields. By retaining only the indispensable components inboard of the plasma torus, principally the cooled toroidal field conductors and in some cases a vacuum containment vessel wall, the fusion reactor features an exceptionally small aspect ratio (typically about 1.5), a naturally elongated plasma cross section without extensive field shaping, requires low strength magnetic containment fields, small size and high beta. These features combine to produce a spherical torus plasma in a unique physics regime which permits compact fusion at low field and modest cost.

Comparison between ray-tracing and physical optics for the computation of light absorption in capillaries--the influence of diffraction and interference.

PubMed

Qin, Yuan; Michalowski, Andreas; Weber, Rudolf; Yang, Sen; Graf, Thomas; Ni, Xiaowu

2012-11-19

Ray-tracing is the commonly used technique to calculate the absorption of light in laser deep-penetration welding or drilling. Since new lasers with high brilliance enable small capillaries with high aspect ratios, diffraction might become important. To examine the applicability of the ray-tracing method, we studied the total absorptance and the absorbed intensity of polarized beams in several capillary geometries. The ray-tracing results are compared with more sophisticated simulations based on physical optics. The comparison shows that the simple ray-tracing is applicable to calculate the total absorptance in triangular grooves and in conical capillaries but not in rectangular grooves. To calculate the distribution of the absorbed intensity ray-tracing fails due to the neglected interference, diffraction, and the effects of beam propagation in the capillaries with sub-wavelength diameter. If diffraction is avoided e.g. with beams smaller than the entrance pupil of the capillary or with very shallow capillaries, the distribution of the absorbed intensity calculated by ray-tracing corresponds to the local average of the interference pattern found by physical optics.

The γγ Physics Program at BESIII

NASA Astrophysics Data System (ADS)

Redmer, C. F.

2018-01-01

A key motivation for the two-photon physics program of the BESIII collaboration is the need of high precision data on electromagnetic transition form factors as input to the calculations of the contribution of hadronic Light-by-light scattering to the anomalous magnetic moment of the muon. The data collected with the BESIII detector allow to study the momentum dependence of the form factors at small momentum transfers, which is of special relevance for αμ. In this presentation the ongoing measurements of the transition form factors of π0,η and η' mesons, as well as pion pairs, are discussed, and the potential for first double-tagged measurements at BESIII are pointed out.

Crime, perceived safety, and physical activity: A meta-analysis.

PubMed

Rees-Punia, Erika; Hathaway, Elizabeth D; Gay, Jennifer L

2018-06-01

Perceived safety from crime and objectively-measured crime rates may be associated with physical inactivity. The purpose of this meta-analysis is to estimate the odds of accumulating high levels of physical activity (PA) when the perception of safety from crime is high and when objectively-measured crime is high. Peer-reviewed studies were identified through PubMed, Web of Science, ProQuest Criminal Justice, and ScienceDirect from earliest record through 2016. Included studies measured total PA, leisure-time PA, or walking in addition to perceived safety from crime or objective measures of crime. Mean odds ratios were aggregated with random effects models, and meta-regression was used to examine effects of potential moderators: country, age, and crime/PA measure. Sixteen cross-sectional studies yielded sixteen effects for perceived safety from crime and four effects for objective crime. Those reporting feeling safe from crime had a 27% greater odds of achieving higher levels of physical activity (OR=1.27 [1.08, 1.49]), and those living in areas with higher objectively-measured crime had a 28% reduced odds of achieving higher levels of physical activity (OR=0.72 [0.61, 0.83]). Effects of perceived safety were highly heterogeneous (I 2 =94.09%), but explored moderators were not statistically significant, likely because of the small sample size. Despite the limited number of effects suitable for aggregation, the mean association between perceived safety and PA was significant. As it seems likely that perceived lack of safety from crime constrains PA behaviors, future research exploring moderators of this association may help guide public health recommendations and interventions. Copyright © 2017 Elsevier Inc. All rights reserved.

Physics evaluation of compact tokamak ignition experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Uckan, N.A.; Houlberg, W.A.; Sheffield, J.

1985-01-01

At present, several approaches for compact, high-field tokamak ignition experiments are being considered. A comprehensive method for analyzing the potential physics operating regimes and plasma performance characteristics of such ignition experiments with O-D (analytic) and 1-1/2-D (WHIST) transport models is presented. The results from both calculations are in agreement and show that there are regimes in parameter space in which a class of small (R/sub o/ approx. 1-2 m), high-field (B/sub o/ approx. 8-13 T) tokamaks with aB/sub o/S/q/sub */ approx. 25 +- 5 and kappa = b/a approx. 1.6-2.0 appears ignitable for a reasonable range of transport assumptions. Consideringmore » both the density and beta limits, an evaluation of the performance is presented for various forms of chi/sub e/ and chi/sub i/, including degradation at high power and sawtooth activity. The prospects of ohmic ignition are also examined. 16 refs., 13 figs.« less

Study of the coupling between real gas effects and rarefied effects on hypersonic aerodynamics

NASA Astrophysics Data System (ADS)

Chen, Song; Hu, Yuan; Sun, Quanhua

2012-11-01

Hypersonic vehicles travel across the atmosphere at very high speed, and the surrounding gas experiences complicated physical and chemical processes. These processes produce real gas effects at high temperature and rarefied gas effects at high altitude where the two effects are coupled through molecular collisions. In this study, we aim to identify the individual real gas and rarefied gas effects by simulating hypersonic flow over a 2D cylinder, a sphere and a blunted cone using a continuum-based CFD approach and the direct simulation Monte Carlo method. It is found that physical processes such as vibrational excitation and chemical reaction will reduce significantly the shock stand-off distance and flow temperature for flows having small Knudsen number. The calculated skin friction and surface heat flux will decrease when the real gas effects are considered in simulations. The trend, however, gets weakened as the Knudsen number increases. It is concluded that the rarefied gas effects weaken the real gas effects on hypersonic flows.

Physical and electrochemical properties of alkaline earth doped, rare earth vanadates

NASA Astrophysics Data System (ADS)

Adijanto, Lawrence; Balaji Padmanabhan, Venu; Holmes, Kevin J.; Gorte, Raymond J.; Vohs, John M.

2012-06-01

The effect of partial substitution of alkaline earth (AE) ions, Sr2+ and Ca2+, for the rare earth (RE) ions, La3+, Ce3+, Pr3+, and Sm3+, on the physical properties of REVO4 compounds were investigated. The use of the Pechini method to synthesize the vanadates allowed for high levels of AE substitution to be obtained. Coulometric titration was used to measure redox isotherms for these materials and showed that the addition of the AE ions increased both reducibility and electronic conductivity under typical solid oxide fuel cell (SOFC) anode conditions, through the formation of compounds with mixed vanadium valence. In spite of their high electronic conductivity, REVO4-yttira stabilized zirconia (YSZ) composite anodes exhibited only modest performance when used in SOFCs operating with H2 fuel at 973 K due to their low catalytic activity. High performance was obtained, however, after the addition of a small amount of catalytically active Pd to the anode.

Physical gelation of a microfiber suspension.

NASA Astrophysics Data System (ADS)

Perazzo, Antonio; Nunes, Janine K.; Guido, Stefano; Stone, Howard A.

2015-11-01

Hydrogels are among the most exploited materials in tissue engineering and there is growing interest in injectable hydrogels, especially as applied to surgical adhesives and bioprinting materials. Here we report a method to produce a hydrogel in a desired location by simply extruding a suspension of high aspect ratio and flexible microfibers from a syringe. The mechanism of gel formation is purely physical and based on irreversible entanglements formed by the microfibers under the action of flow. The single microfibers have been produced and finely tailored by microfluidic methods. Shear rheology has been performed in order to get insights on the entanglements, and results show that the formation of entanglements is related to a shear thickening behavior of the suspension, which in turn depends on shear rate and concentration of fibers. When shearing the suspension, highly non-linear viscoelastic behavior is observed and probed by a highly positive first normal stress difference. We also report the hydrogel swelling behavior and its linear viscoelastic properties as obtained by imposing small oscillatory stress to the material.

Modeling of a heat sink and high heat flux vapor chamber

NASA Astrophysics Data System (ADS)

Vadnjal, Aleksander

An increasing demand for a higher heat flux removal capability within a smaller volume for high power electronics led us to focus on a novel cold plate design. A high heat flux evaporator and micro channel heat sink are the main components of a cold plate which is capable of removing couple of 100 W/cm2. In order to describe performance of such porous media device a proper modeling has to be addressed. A universal approach based on the volume average theory (VAT) to transport phenomena in porous media is shown. An approach on how to treat the closure for momentum and energy equations is addressed and a proper definition for friction factors and heat transfer coefficients are discussed. A numerical scheme using a solution to Navier-Stokes equations over a representative elementary volume (REV) and the use of VAT is developed to show how to compute friction factors and heat transfer coefficients. The calculation show good agreement with the experimental data. For the heat transfer coefficient closure, a proper average for both fluid and solid is investigated. Different types of heating are also investigated in order to determine how it influences the heat transfer coefficient. A higher heat fluxes in small area condensers led us to the micro channels in contrast to the classical heat fin design. A micro channel can have various shapes to enhance heat transfer, but the shape that will lead to a higher heat flux removal with a moderate pumping power needs to be determined. The standard micro-channel terminology is usually used for channels with a simple cross section, e.g. square, round, triangle, etc., but here the micro channel cross section is going to be expanded to describe more complicated and interconnected micro scale channel cross sections. The micro channel geometries explored are pin fins (in-line and staggered) and sintered porous micro channels. The problem solved here is a conjugate problem involving two heat transfer mechanisms; (1) porous media conductivity and (2) internal heat transfer coefficient. Volume averaging theory (VAT) is used to rigorously cast the point wise conservation of energy, momentum and mass equations into a form that represents the thermal and hydraulic properties of the micro channel (porous media) morphology. Using the resulting VAT based field equations, optimization of a micro channel heated from one side is used to determine the optimum micro channel morphology. A small square of 1 cm2 is chosen as an example and the thermal resistance, 0C/W, and pressure drop are shown as a function of Reynolds number. The high heat flux removal on small surfaces at moderately small temperatures is achieved by bi-porous evaporator The device was analyzed with the possibility of heat flux magnitudes exceeding 1kW/cm2 by using advantages of a dual pore structure of a bi-porous wick. The heat transfer model of a thin bi-porous wick is developed and it incorporates thermo-physical properties of a bi-porous media. It is shown that physics of heat removal is characterized in three stages; conduction, big pore drying out and small pore drying out. The operating conditions of the wick have to be in a safe margin away from the total dry out. A complete dry out of the wick inevitably leads to the burn out, therefore more concern has been added to modeling of big pore dry out, since this will be a desired operational. The construction of the boiling/evaporation curves was successfully constructed by the model showing that the physic of heat removal on two different length scales is governed by thermo-physical properties for the appropriate scale. The model shows good prediction for various combinations of big and small pores size in the bi-porous wicks tested.

Digital Rock Physics Aplications: Visualisation Complex Pore and Porosity-Permeability Estimations of the Porous Sandstone Reservoir

NASA Astrophysics Data System (ADS)

Handoyo; Fatkhan; Del, Fourier

2018-03-01

Reservoir rock containing oil and gas generally has high porosity and permeability. High porosity is expected to accommodate hydrocarbon fluid in large quantities and high permeability is associated with the rock’s ability to let hydrocarbon fluid flow optimally. Porosity and permeability measurement of a rock sample is usually performed in the laboratory. We estimate the porosity and permeability of sandstones digitally by using digital images from μCT-Scan. Advantages of the method are non-destructive and can be applied for small rock pieces also easily to construct the model. The porosity values are calculated by comparing the digital image of the pore volume to the total volume of the sandstones; while the permeability values are calculated using the Lattice Boltzmann calculations utilizing the nature of the law of conservation of mass and conservation of momentum of a particle. To determine variations of the porosity and permeability, the main sandstone samples with a dimension of 300 × 300 × 300 pixels are made into eight sub-cubes with a size of 150 × 150 × 150 pixels. Results of digital image modeling fluid flow velocity are visualized as normal velocity (streamline). Variations in value sandstone porosity vary between 0.30 to 0.38 and permeability variations in the range of 4000 mD to 6200 mD. The results of calculations show that the sandstone sample in this research is highly porous and permeable. The method combined with rock physics can be powerful tools for determining rock properties from small rock fragments.

Physical-depth architectural requirements for generating universal photonic cluster states

NASA Astrophysics Data System (ADS)

Morley-Short, Sam; Bartolucci, Sara; Gimeno-Segovia, Mercedes; Shadbolt, Pete; Cable, Hugo; Rudolph, Terry

2018-01-01

Most leading proposals for linear-optical quantum computing (LOQC) use cluster states, which act as a universal resource for measurement-based (one-way) quantum computation. In ballistic approaches to LOQC, cluster states are generated passively from small entangled resource states using so-called fusion operations. Results from percolation theory have previously been used to argue that universal cluster states can be generated in the ballistic approach using schemes which exceed the critical threshold for percolation, but these results consider cluster states with unbounded size. Here we consider how successful percolation can be maintained using a physical architecture with fixed physical depth, assuming that the cluster state is continuously generated and measured, and therefore that only a finite portion of it is visible at any one point in time. We show that universal LOQC can be implemented using a constant-size device with modest physical depth, and that percolation can be exploited using simple pathfinding strategies without the need for high-complexity algorithms.

Effects of a 10-week multimodal exercise program on physical and cognitive function of nursing home residents: a psychomotor intervention pilot study.

PubMed

Pereira, Catarina; Rosado, Hugo; Cruz-Ferreira, Ana; Marmeleira, José

2018-05-01

Nursing home institutionalization tends to exacerbate loss of functioning. Examine the feasibility and the effect of a psychomotor intervention-a multimodal exercise program promoting simultaneous cognitive and motor stimulation-on the executive (planning ability and selective attention) and physical function of nursing home residents. Seventeen participants engaged in a 10-week multimodal exercise program and 17 maintained usual activities. Exercise group improved planning ability (25-32%), selective attention (19-67%), and physical function [aerobic endurance, lower body strength, agility, balance, gait, and mobility (19-41%)], corresponding to an effect size ranging from 0.29 (small) to 1.11 (high), p < 0.05. The multimodal exercise program was feasible and well tolerated. The program improved executive and physical functions of the nursing home residents, reverting the usual loss of both cognitive and motor functioning in older adult institutionalized. Multimodal exercise programs may help to maintain or improve nursing home residents' functioning.

Nuclear spectroscopy with Geant4. The superheavy challenge

NASA Astrophysics Data System (ADS)

Sarmiento, Luis G.

2016-12-01

The simulation toolkit Geant4 was originally developed at CERN for high-energy physics. Over the years it has been established as a swiss army knife not only in particle physics but it has seen an accelerated expansion towards nuclear physics and more recently to medical imaging and γ- and ion- therapy to mention but a handful of new applications. The validity of Geant4 is vast and large across many particles, ions, materials, and physical processes with typically various different models to choose from. Unfortunately, atomic nuclei with atomic number Z > 100 are not properly supported. This is likely due to the rather novelty of the field, its comparably small user base, and scarce evaluated experimental data. To circumvent this situation different workarounds have been used over the years. In this work the simulation toolkit Geant4 will be introduced with its different components and the effort to bring the software to the heavy and superheavy region will be described.

Factors associated with inadequate work ability among women in the clothing industry.

PubMed

Augusto, Viviane Gontijo; Sampaio, Rosana Ferreira; Ferreira, Fabiane Ribeiro; Kirkwood, Renata Noce; César, Cibele Comini

2015-01-01

Work ability depends on a balance between individual resources and work demands. This study evaluated factors that are associated with inadequate work ability among workers in the clothing industry. We conducted a cross-sectional observational study of 306 workers in 40 small and medium-sized enterprises. We assessed work ability, individual resources, physical and psychosocial demands, and aspects of life outside work using a binary logistic regression model with hierarchical data entry. The mean work ability was 42.5 (SD=3.5); when adjusted for age, only 11% of the workers showed inadequate work ability. The final model revealed that smoking, high isometric physical load, and poor physical environmental conditions were the most significant predictors of inadequate work ability. Good working conditions and worker education must be implemented to eliminate factors that can be changed and that have a negative impact on work ability. These initiatives include anti-smoking measures, improved postures at work, and better physical environmental conditions.

Indoor Tracking to Understand Physical Activity and Sedentary Behaviour: Exploratory Study in UK Office Buildings

PubMed Central

Spinney, Richard; Smith, Lee; Ucci, Marcella; Fisher, Abigail; Konstantatou, Marina; Sawyer, Alexia; Wardle, Jane; Marmot, Alexi

2015-01-01

Little is known of the patterns of physical activity, standing and sitting by office workers. However, insight into these behaviours is of growing interest, notably in regard to public health priorities to reduce non-communicable disease risk factors associated with high levels of sitting time and low levels of physical activity. With the advent and increasing availability of indoor tracking systems it is now becoming possible to build detailed pictures of the usage of indoor spaces. This paper reports initial results of indoor tracking used in conjunction with the ActivPAL activity monitoring device. In this paper we give an overview of the usage of the tracking system and its installation and illustrate some of the resultant data. We also provide preliminary results that investigate the relationship between location, light physical activity and sitting in a small sample of office workers (n=33) from two separate office environments in order to demonstrate the relevance and explanatory power of the technique. PMID:25993515

Active Learning Strategies for Introductory Light and Optics

NASA Astrophysics Data System (ADS)

Sokoloff, David R.

2016-01-01

There is considerable evidence that traditional approaches are ineffective in teaching physics concepts, including light and optics concepts. A major focus of the work of the Activity Based Physics Group has been on the development of active learning curricula like RealTime Physics (RTP) labs and Interactive Lecture Demonstrations (ILDs). Among the characteristics of these curricula are: (1) use of a learning cycle in which students are challenged to compare predictions—discussed with their peers in small groups—to observations of the physical world, (2) use of guided hands-on work to construct basic concepts from observations, and (3) use of computer-based tools. It has been possible to change the lecture and laboratory learning environments at a large number of universities, colleges, and high schools without changing the structure of the introductory course. For example, in the United States, nearly 200 physics departments have adopted RTP, and many others use pre-publication, open-source versions or have adopted the RTP approach to develop their own labs. Examples from RTP and ILDs (including optics magic tricks) are described in this paper.

Using CubeSats to Monitor Debris Flux

NASA Technical Reports Server (NTRS)

Matney, Mark

2016-01-01

Recent updates to NASA's Orbital Debris Engineering Model (ORDEM 3.0) include a population of small particles (1-2 mm in size) composed of high-density materials (e.g., steel) that drive much of the predicted risk for satellites in the 700-1000 km altitude regime. This modeled population was based on the analysis of returned surfaces of the Shuttle, which flew below 600 km altitude. The cessation of Shuttle missions, plus the lack of in situ data above 600 km means that a data source is being sought to either confirm or modify this high-density population. One possible data source would be a database of anomalous sporadic changes in spacecraft orbit/orientation that might be due to momentum transfer from small particles too small to seriously damage the spacecraft. Because the momentum imparted from an impact would be tiny, it would most likely show up in the orbital behavior of cubesats and other small satellites. While such small satellites were few in number, this was not a particularly attractive option, but now with the proliferation of cubesats in multiple orbit planes and altitudes, the possible collecting area has increased significantly. This presentation will discuss the physics of momentum-transferring impacts from hypervelocity collisions, and make predictions about rates, directions, and locations of such impacts. In addition, it will include recommendations for satellite users on what kind of data might be worth archiving and investigating.

Force level EW in the Australian Defence Force

NASA Astrophysics Data System (ADS)

Finn, Anthony; Chalmers, Greg; Pincombe, Adrian

2001-08-01

The Australian Defence Force is a small force, dependent upon a few high value assets that act as force multipliers. Consequently, it cannot afford to sustain high attrition. The current Concept of Operations for these platforms is to operate them outside the threat envelope. Organic sensors and data links are used to maintain Situational Awareness, Combat Air Patrol is used to intercept hostile missile launch platforms, and Electronic Warfare self-protection is used as a last resort. Unfortunately, it is common for such high value assets to be slowly, non-stealthy, low agility, physically large platforms that follow predictable trajectories. Consequently, they are easy to target and track from a long range and have a high `sitting duck' factor.

Relationship of physical activity to fundamental movement skills among adolescents.

PubMed

Okely, A D; Booth, M L; Patterson, J W

2001-11-01

To determine the relationship of participation in organized and nonorganized physical activity with fundamental movement skills among adolescents. Male and female children in Grade 8 (mean age, 13.3 yr) and Grade 10 (mean age, 15.3 yr) were assessed on six fundamental movement skills (run, vertical jump, catch, overhand throw, forehand strike, and kick). Physical activity was assessed using a self-report recall measure where students reported the type, duration, and frequency of participation in organized physical activity and nonorganized physical activity during a usual week. Multiple regression analysis indicated that fundamental movement skills significantly predicted time in organized physical activity, although the percentage of variance it could explain was small. This prediction was stronger for girls than for boys. Multiple regression analysis showed no relationship between time in nonorganized physical activity and fundamental movement skills. Fundamental movement skills are significantly associated with adolescents' participation in organized physical activity, but predict only a small portion of it.

The 7/8 Piano Keyboard: An Attractive Alternative for Small-Handed Players

ERIC Educational Resources Information Center

Wristen, Brenda; Hallbeck, M. Susan

2009-01-01

This study examines whether the use of a 7/8 keyboard contributes to the physical ease of small-handed pianists in comparison to the conventional piano keyboard. A secondary research question focuses on the progression of physical ease in making the transition from one keyboard to the other. For the purposes of this study, the authors stipulated…

Comparison of Two Small-Group Learning Methods in 12th-Grade Physics Classes Focusing on Intrinsic Motivation and Academic Performance

ERIC Educational Resources Information Center

Berger, Roland; Hanze, Martin

2009-01-01

Twelfth-grade physics classes with 344 students participated in a quasi-experimental study comparing two small-group learning settings. In the jigsaw classroom, in contrast to the cyclical rotation method, teaching expectancy as well as resource interdependence is established. The study is based on the self-determination theory of motivation,…

IPA (v1): a framework for agent-based modelling of soil water movement

NASA Astrophysics Data System (ADS)

Mewes, Benjamin; Schumann, Andreas H.

2018-06-01

In the last decade, agent-based modelling (ABM) became a popular modelling technique in social sciences, medicine, biology, and ecology. ABM was designed to simulate systems that are highly dynamic and sensitive to small variations in their composition and their state. As hydrological systems, and natural systems in general, often show dynamic and non-linear behaviour, ABM can be an appropriate way to model these systems. Nevertheless, only a few studies have utilized the ABM method for process-based modelling in hydrology. The percolation of water through the unsaturated soil is highly responsive to the current state of the soil system; small variations in composition lead to major changes in the transport system. Hence, we present a new approach for modelling the movement of water through a soil column: autonomous water agents that transport water through the soil while interacting with their environment as well as with other agents under physical laws.

Investigating the Mobility of Light Autonomous Tracked Vehicles using a High Performance Computing Simulation Capability

NASA Technical Reports Server (NTRS)

Negrut, Dan; Mazhar, Hammad; Melanz, Daniel; Lamb, David; Jayakumar, Paramsothy; Letherwood, Michael; Jain, Abhinandan; Quadrelli, Marco

2012-01-01

This paper is concerned with the physics-based simulation of light tracked vehicles operating on rough deformable terrain. The focus is on small autonomous vehicles, which weigh less than 100 lb and move on deformable and rough terrain that is feature rich and no longer representable using a continuum approach. A scenario of interest is, for instance, the simulation of a reconnaissance mission for a high mobility lightweight robot where objects such as a boulder or a ditch that could otherwise be considered small for a truck or tank, become major obstacles that can impede the mobility of the light autonomous vehicle and negatively impact the success of its mission. Analyzing and gauging the mobility and performance of these light vehicles is accomplished through a modeling and simulation capability called Chrono::Engine. Chrono::Engine relies on parallel execution on Graphics Processing Unit (GPU) cards.

Modeling of subcooling and solidification of phase change materials

NASA Astrophysics Data System (ADS)

Günther, Eva; Mehling, Harald; Hiebler, Stefan

2007-12-01

Phase change materials (PCM) are able to store thermal energy in small temperature intervals very efficiently due to their high latent heat. Particularly high storage capacity is found in salt hydrates. Salt hydrates however often show subcooling, thus inhibiting the release of the stored heat. In the state of the art simulations of PCM, the effect of subcooling is almost always neglected. This is a practicable approach for small subcooling, but it is problematic for subcooling in the order of the driving temperature gradient on unloading the storage. In this paper, we first present a new algorithm to simulate subcooling in a physically proper way. Then, we present a parametric study to demonstrate the main features of the algorithm and a comparison of computed and experimentally obtained data. The new algorithm should be particularly useful in simulating applications with low cooling rates, for example building applications.

Optimization of the scan protocols for CT-based material extraction in small animal PET/CT studies

NASA Astrophysics Data System (ADS)

Yang, Ching-Ching; Yu, Jhih-An; Yang, Bang-Hung; Wu, Tung-Hsin

2013-12-01

We investigated the effects of scan protocols on CT-based material extraction to minimize radiation dose while maintaining sufficient image information in small animal studies. The phantom simulation experiments were performed with the high dose (HD), medium dose (MD) and low dose (LD) protocols at 50, 70 and 80 kVp with varying mA s. The reconstructed CT images were segmented based on Hounsfield unit (HU)-physical density (ρ) calibration curves and the dual-energy CT-based (DECT) method. Compared to the (HU;ρ) method performed on CT images acquired with the 80 kVp HD protocol, a 2-fold improvement in segmentation accuracy and a 7.5-fold reduction in radiation dose were observed when the DECT method was performed on CT images acquired with the 50/80 kVp LD protocol, showing the possibility to reduce radiation dose while achieving high segmentation accuracy.

Manifestations of the rotation and gravity of the Earth in high-energy physics experiments

NASA Astrophysics Data System (ADS)

Obukhov, Yuri N.; Silenko, Alexander J.; Teryaev, Oleg V.

2016-08-01

The inertial (due to rotation) and gravitational fields of the Earth affect the motion of an elementary particle and its spin dynamics. This influence is not negligible and should be taken into account in high-energy physics experiments. Earth's influence is manifest in perturbations in the particle motion, in an additional precession of the spin, and in a change of the constitutive tensor of the Maxwell electrodynamics. Bigger corrections are oscillatory, and their contributions average to zero. Other corrections due to the inhomogeneity of the inertial field are not oscillatory but they are very small and may be important only for the storage ring electric dipole moment experiments. Earth's gravity causes the Newton-like force, the reaction force provided by a focusing system, and additional torques acting on the spin. However, there are no observable indications of the electromagnetic effects due to Earth's gravity.

Spatial characterization of Bessel-like beams for strong-field physics.

PubMed

Summers, Adam M; Yu, Xiaoming; Wang, Xinya; Raoul, Maxime; Nelson, Josh; Todd, Daniel; Zigo, Stefan; Lei, Shuting; Trallero-Herrero, Carlos A

2017-02-06

We present a compact, simple design for the generation and tuning of both the spot size and effective focal length of Bessel-like beams. In particular, this setup provides an important tool for the use of Bessel-like beams with high-power, femtosecond laser systems. Using a shallow angle axicon in conjunction with a spherical lens, we show that it is possible to focus Bessel-like modes to comparable focal spot sizes to sharp axicons while maintaining a long effective focal length. The resulting focal profiles are characterized in detail using an accurate high dynamic range imaging technique. Quantitatively, we introduce a metric (R_0.8) which defines the spot-size containing 80% of the total energy. Our setup overcomes the typical compromise between long working distances and small spot sizes. This is particularly relevant for strong-field physics where most experiments must operate in vacuum.

First Operational Experience With a High-Energy Physics Run Control System Based on Web Technologies

NASA Astrophysics Data System (ADS)

Bauer, Gerry; Beccati, Barbara; Behrens, Ulf; Biery, Kurt; Branson, James; Bukowiec, Sebastian; Cano, Eric; Cheung, Harry; Ciganek, Marek; Cittolin, Sergio; Coarasa Perez, Jose Antonio; Deldicque, Christian; Erhan, Samim; Gigi, Dominique; Glege, Frank; Gomez-Reino, Robert; Gulmini, Michele; Hatton, Derek; Hwong, Yi Ling; Loizides, Constantin; Ma, Frank; Masetti, Lorenzo; Meijers, Frans; Meschi, Emilio; Meyer, Andreas; Mommsen, Remigius K.; Moser, Roland; O'Dell, Vivian; Oh, Alexander; Orsini, Luciano; Paus, Christoph; Petrucci, Andrea; Pieri, Marco; Racz, Attila; Raginel, Olivier; Sakulin, Hannes; Sani, Matteo; Schieferdecker, Philipp; Schwick, Christoph; Shpakov, Dennis; Simon, Michal; Sumorok, Konstanty; Yoon, Andre Sungho

2012-08-01

Run control systems of modern high-energy particle physics experiments have requirements similar to those of today's Internet applications. The Compact Muon Solenoid (CMS) collaboration at CERN's Large Hadron Collider (LHC) therefore decided to build the run control system for its detector based on web technologies. The system is composed of Java Web Applications distributed over a set of Apache Tomcat servlet containers that connect to a database back-end. Users interact with the system through a web browser. The present paper reports on the successful scaling of the system from a small test setup to the production data acquisition system that comprises around 10.000 applications running on a cluster of about 1600 hosts. We report on operational aspects during the first phase of operation with colliding beams including performance, stability, integration with the CMS Detector Control System and tools to guide the operator.

Progress in high-energy cosmic ray physics

NASA Astrophysics Data System (ADS)

Mollerach, S.; Roulet, E.

2018-01-01

We review some of the recent progress in our knowledge about high-energy cosmic rays, with an emphasis on the interpretation of the different observational results. We discuss the effects that are relevant to shape the cosmic ray spectrum and the explanations proposed to account for its features and for the observed changes in composition. The physics of air-showers is summarized and we also present the results obtained on the proton-air cross section and on the muon content of the showers. We discuss the cosmic ray propagation through magnetic fields, the effects of diffusion and of magnetic lensing, the cosmic ray interactions with background radiation fields and the production of secondary neutrinos and photons. We also consider the cosmic ray anisotropies, both at large and small angular scales, presenting the results obtained from the TeV up to the highest energies and discuss the models proposed to explain their origin.

AUV based study on physical and ecological processes at fronts

NASA Astrophysics Data System (ADS)

Tippenhauer, Sandra; Wulff, Thorben; Von Appen, Wilken-Jon

2017-04-01

Small-scale processes and their effects get more and more attention when it comes to understanding processes and changes in the (Arctic) ocean. Here we present a study on physical processes and ecological responses at submesoscale frontal systems in the Fram Strait investigated using an autonomous underwater vehicle (AUV). The AUV is equipped with physical and biogeochemical sensors such as an acoustic Doppler current profiler, a turbulence probe, a conductivity-temperature-depth probe, and sensors for Oxygen, Nitrate, Chlorophyll a, and photosynthetically active radiation (PAR). The study is designed such that the AUV covers tracks of several kilometers length in cross-frontal direction with the front roughly located in the middle of the track. On its way, the AUV records high-resolution vertical or zigzag profiles of the physical and biogeochemical properties in the upper 50 m which includes the euphotic zone. In both, physical and biogeochemical terms, the measurements revealed a complex structure of the water column. At the fronts the distribution of phytoplankton and nutrients was highly inhomogeneous, possibly due to wind-driven frontogenesis or the growth of mixed layer eddies. To set the observations into a larger context we also examine ship-based and satellite data. We investigate how the observed patterns of the potential vorticity and the biogeochemical properties may be formed and which processes could lead to a smoothing of the observed gradients.

Trajectories of perceived emotional and physical distress in patients with an implantable cardioverter defibrillator.

PubMed

van den Broek, Krista C; Kupper, Nina; van der Voort, Pepijn H; Alings, Marco; Denollet, Johan; Nyklíček, Ivan

2014-02-01

Little is known about the course of emotional and physical distress in patients with an implantable cardioverter defibrillator (ICD). We examined (1) trajectories of emotional and physical distress in the first 18 months postimplantation and (2) predictors of these trajectories, including demographical, clinical, and personality factors. Dutch patients with an ICD (N = 645) completed measures on anxiety, depression, somatic symptoms, and perceived disability at the time of implantation, and 2, 12, and 18 months postimplantation. Measures on Type D personality (tendency to inhibit the expression of negative emotions) and anxiety sensitivity (tendency to fear anxiety-related sensations) were also completed at baseline. Latent class analysis (LatentGOLD) identified six to seven distinct trajectories, varying largely in overall levels of distress, and remaining relatively stable after a small initial decline. Multinomial regression showed that Type D personality and anxiety sensitivity were the most prominent predictors, particularly of trajectories that reflected higher distress levels. Cardiac resynchronization therapy and coronary artery disease also increased the risk for distress, whereas ICD indication and shocks did not. The course of emotional and physical distress may be relatively stable after ICD implantation. In clinical practice, identification of patients with high risk of higher levels of emotional and physical distress may be warranted; as such, patients with high levels of anxiety sensitivity or a Type D personality should be identified and offered behavioral support.

Neuromuscular and inflammatory responses to handball small-sided games: the effects of physical contact.

PubMed

Dello Iacono, A; Eliakim, A; Padulo, J; Laver, L; Ben-Zaken, S; Meckel, Y

2017-10-01

The aim of this study was to investigate the influence of physical contact on neuromuscular impairments and inflammatory response during handball small-sided games. Using a counterbalanced design, 12 elite male junior handball players were divided into two groups: contact (C-SSG) and no-contact (NC-SSG), performing both contact and no-contact small-sided games, in reverse order on two training sessions separated by 5 days. The methodology and rules were identical for the two SSG regimens, with the only difference being the inclusion or prohibition of upper body use for physical contacts. Upper and lower body neuromuscular performances and blood concentrations of inflammatory cytokine IL-6 were assessed before and immediately after the games. During small-sided games, video analysis was used to establish the physical contact counts. Significant differences were found in most upper and lower limbs muscles kinetic variables and in the physical contact events (all P < 0.001) following the two training regimens. There was an increase in IL-6 after C-SSG and no changes following NC-SSG (P < 0.05 and P = 0.12, respectively). Moreover, a strong correlation was found between the number of physical contacts and IL-6 responses (r = 0.971, P < 0.001) in C-SSG. This study indicates that an inflammatory response and large upper and lower body neuromuscular impairments result from physical contact in elite handball players. These outcomes outline the specific physiological profile of C-SSG that, in turn, might be used by practitioners and coaches as a practical approach to strategically select exercises in athlete's overall training program. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Health-related effects of worksite interventions involving physical exercise and reduced workhours.

PubMed

von Thiele Schwarz, Ulrica; Lindfors, Petra; Lundberg, Ulf

2008-06-01

This study examined the health-related effects of two worksite interventions, physical exercise and reduced workhours, on women employed in dentistry. Six workplaces were randomized to one of the following three conditions: (i) 2.5 hours of weekly, mandatory physical exercise of middle-to-high intensity to be performed during workhours (N=62), (ii) a reduction of full-time weekly workhours from 40 to 37.5 hours (N=50), and (iii) reference. In all, 177 women participated. Biomarkers and self-ratings in questionnaires were obtained before the intervention (T (1)), and six (T (2)) and 12 months (T (3)) after the intervention. The results showed increased levels of physical activity and exercise in all of the groups, the level of physical exercise being significantly greater in the physical exercise group. Repeated-measures analyses of variance using data from T (1)and T (3)for biological measures and all three time points for self-ratings produced significant interaction effects for glucose, waist-to-hip ratio, and work ability and clear trends for general symptoms and upper-extremity disorders. Posthoc analyses showed that the results of the health-related measures differed between the interventions, decreased glucose and upper-extremity disorders in the exercise group, and increased high-density lipoprotein and waist-to-hip ratio among those working reduced hours. These results show that the two interventions had small and varied effects on biomarkers and self-reports of different aspects of health among women. It is suggested that interventions involving a modest reduction in workhours seem to be more effective if these hours are used for physical exercise.

Physical limits to biochemical signaling

NASA Astrophysics Data System (ADS)

Bialek, William; Setayeshgar, Sima

2005-07-01

Many crucial biological processes operate with surprisingly small numbers of molecules, and there is renewed interest in analyzing the impact of noise associated with these small numbers. Twenty-five years ago, Berg and Purcell showed that bacterial chemotaxis, where a single-celled organism must respond to small changes in concentration of chemicals outside the cell, is limited directly by molecule counting noise and that aspects of the bacteria's behavioral and computational strategies must be chosen to minimize the effects of this noise. Here, we revisit and generalize their arguments to estimate the physical limits to signaling processes within the cell and argue that recent experiments are consistent with performance approaching these limits. Author contributions: W.B. and S.S. designed research, performed research, and wrote the paper.†Present address: Department of Physics, Indiana University, Bloomington, IN 47405.

Investigation of the Dynamics of Low-Tension Cables

DTIC Science & Technology

1992-06-01

chapter 3. An implicit time domain routine is nec- essary as the high propagation speed of elastic waves would require prohibitively small time-step...singularities by ensuring smooth curvature. However, sustained boundary layers are found to develop, demonstrating the importance of the underlying physical...chain and elastic chain, EA* = 4.0 x 103 ............... 124 3.10 Mode shape for tension variation due to elastic waves , using EA* - 4.0 x 103.125 6.11

Quantum Loop Expansion to High Orders, Extended Borel Summation, and Comparison with Exact Results

NASA Astrophysics Data System (ADS)

Noreen, Amna; Olaussen, Kåre

2013-07-01

We compare predictions of the quantum loop expansion to (essentially) infinite orders with (essentially) exact results in a simple quantum mechanical model. We find that there are exponentially small corrections to the loop expansion, which cannot be explained by any obvious “instanton”-type corrections. It is not the mathematical occurrence of exponential corrections but their seeming lack of any physical origin which we find surprising and puzzling.

Simulating Complex Satellites and a Space-Based Surveillance Sensor Simulation

DTIC Science & Technology

2009-09-01

high-resolution imagery (Fig. 1). Thus other means for characterizing satellites will need to be developed. Research into non- resolvable space object...computing power and time . The second way, which we are using here is to create simpler models of satellite bodies and use albedo-area calculations...their position, movement, size, and physical features. However, there are many satellites in orbit that are simply too small or too far away to resolve by

Second-generation DNA-templated macrocycle libraries for the discovery of bioactive small molecules.

PubMed

Usanov, Dmitry L; Chan, Alix I; Maianti, Juan Pablo; Liu, David R

2018-07-01

DNA-encoded libraries have emerged as a widely used resource for the discovery of bioactive small molecules, and offer substantial advantages compared with conventional small-molecule libraries. Here, we have developed and streamlined multiple fundamental aspects of DNA-encoded and DNA-templated library synthesis methodology, including computational identification and experimental validation of a 20 × 20 × 20 × 80 set of orthogonal codons, chemical and computational tools for enhancing the structural diversity and drug-likeness of library members, a highly efficient polymerase-mediated template library assembly strategy, and library isolation and purification methods. We have integrated these improved methods to produce a second-generation DNA-templated library of 256,000 small-molecule macrocycles with improved drug-like physical properties. In vitro selection of this library for insulin-degrading enzyme affinity resulted in novel insulin-degrading enzyme inhibitors, including one of unusual potency and novel macrocycle stereochemistry (IC 50  = 40 nM). Collectively, these developments enable DNA-templated small-molecule libraries to serve as more powerful, accessible, streamlined and cost-effective tools for bioactive small-molecule discovery.

Focused Research Group in Correlated Electron and Complex Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Ziqiang

While the remarkable physical properties of correlated and complex electronic materials hold great promise for technological applications, one of the key values of the research in this field is its profound impact on fundamental physics. The transition metal oxides, pnictides, and chalcogenides play a key role and occupy an especially important place in this field. The basic reason is that the outer shell of transition metals contains the atomic d-orbitals that have small spatial extent, but not too small to behave as localized orbtials. These d-electrons therefore have a small wave function overlap in a solid, e.g. in an octahedralmore » environment, and form energy bands that are relatively narrow and on the scale of the short-range intra-atomic Coulomb repulsion (Hubbard U). In this intermediate correlation regime lies the challenge of the many-body physics responsible for new and unconventional physical properties. The study of correlated electron and complex materials represents both the challenge and the vitality of condensed matter and materials physics and often demands close collaborations among theoretical and experimental groups with complementary techniques. Our team has a track record and a long-term research goal of studying the unusual complexities and emergent behaviors in the charge, spin, and orbital sectors of the transition metal compounds in order to gain basic knowledge of the quantum electronic states of matter. During the funding period of this grant, the team continued their close collaborations between theory, angle-resolved photoemission spectroscopy, and scanning tunneling microscopy and made significant progress and contributions to the field of iron-based superconductors, copper-oxide high-temperature superconductors, triangular lattice transition metal oxide cobaltates, strontium ruthenates, spin orbital coupled iridates, as well as topological insulators and other topological quantum states of matter. These results include both new discoveries and the resolution to outstanding and unresolved issues. It should be emphasized that the DOE funding provided the crucial support for the close and meaningful collaborations of the focused research group that go far beyond simply putting the research papers from each group together. Indeed, the majority of the publications involved multiple PIs and collaborations between theory and experiments.« less

Talbot-Lau x-ray interferometry for high energy density plasma diagnostic.

PubMed

Stutman, D; Finkenthal, M

2011-11-01

High resolution density diagnostics are difficult in high energy density laboratory plasmas (HEDLP) experiments due to the scarcity of probes that can penetrate above solid density plasmas. Hard x-rays are one possible probe for such dense plasmas. We study the possibility of applying an x-ray method recently developed for medical imaging, differential phase-contrast with Talbot-Lau interferometers, for the diagnostic of electron density and small-scale hydrodynamic instabilities in HEDLP experiments. The Talbot method uses micro-periodic gratings to measure the refraction and ultra-small angle scatter of x-rays through an object and is attractive for HEDLP diagnostic due to its capability to work with incoherent and polychromatic x-ray sources such as the laser driven backlighters used for HEDLP radiography. Our paper studies the potential of the Talbot method for HEDLP diagnostic, its adaptation to the HEDLP environment, and its extension of high x-ray energy using micro-periodic mirrors. The analysis is illustrated with experimental results obtained using a laboratory Talbot interferometer. © 2011 American Institute of Physics

Robotic Missions to Small Bodies and Their Potential Contributions to Human Exploration and Planetary Defense

NASA Technical Reports Server (NTRS)

Abell, Paul A.; Rivkin, Andrew S.

2015-01-01

Introduction: Robotic missions to small bodies will directly address aspects of NASA's Asteroid Initiative and will contribute to future human exploration and planetary defense. The NASA Asteroid Initiative is comprised of two major components: the Grand Challenge and the Asteroid Mission. The first component, the Grand Challenge, focuses on protecting Earth's population from asteroid impacts by detecting potentially hazardous objects with enough warning time to either prevent them from impacting the planet, or to implement civil defense procedures. The Asteroid Mission involves sending astronauts to study and sample a near-Earth asteroid (NEA) prior to conducting exploration missions of the Martian system, which includes Phobos and Deimos. The science and technical data obtained from robotic precursor missions that investigate the surface and interior physical characteristics of an object will help identify the pertinent physical properties that will maximize operational efficiency and reduce mission risk for both robotic assets and crew operating in close proximity to, or at the surface of, a small body. These data will help fill crucial strategic knowledge gaps (SKGs) concerning asteroid physical characteristics that are relevant for human exploration considerations at similar small body destinations. These data can also be applied for gaining an understanding of pertinent small body physical characteristics that would also be beneficial for formulating future impact mitigation procedures. Small Body Strategic Knowledge Gaps: For the past several years NASA has been interested in identifying the key SKGs related to future human destinations. These SKGs highlight the various unknowns and/or data gaps of targets that the science and engineering communities would like to have filled in prior to committing crews to explore the Solar System. An action team from the Small Bodies Assessment Group (SBAG) was formed specifically to identify the small body SKGs under the direction of the Human Exploration and Operations Missions Directorate (HEOMD), given NASA's recent interest in NEAs and the Martian moons as potential human destinations. The action team organized the SKGs into four broad themes: 1) Identify human mission targets; 2) Understand how to work on and interact with the small body surface; 3) Understand the small body environment and its potential risk/benefit to crew, systems, and operational assets; and 4) Understand the small body resource potential. Of these four SKG themes, the first three have significant overlap with planetary defense considerations. The data obtained from investigations of small body physical characteristics under these three themes can be directly applicable to planetary defense initiatives. Conclusions: Missions to investigate small bodies can address small body strategic knowledge gaps and contribute to the overall success for human exploration missions to asteroids and the Martian moons. In addition, such reconnaissance of small bodies can also provide a wealth of information relevant to the science and planetary defense of NEAs.

V. S. Lebedev and I. L. Beigman, Physics of Highly Excited Atoms and Ions

NASA Astrophysics Data System (ADS)

Mewe, R.

1999-07-01

This book contains a comprehensive description of the basic principles of the theoretical spectroscopy and experimental spectroscopic diagnostics of Rydberg atoms and ions, i.e., atoms in highly excited states with a very large principal quantum number (n≫1). Rydberg atoms are characterized by a number of peculiar physical properties as compared to atoms in the ground or a low excited state. They have a very small ionization potential (∝1/n2), the highly excited electron has a small orbital velocity (∝1/n), the radius (∝n2) is very large, the excited electron has a long orbital period (∝n3), and the radiation lifetime is very long (∝n3-5). At the same time the R. atom is very sensitive to perturbations from external fields in collisions with charged and neutral targets. In recent years, R. atoms have been observed in laboratory and cosmic conditions for n up to ˜1000, which means that the size amounts to about 0.1 mm, ˜106 times that of an atom in the ground state. The scope of this monograph is to familiarize the reader with today's approaches and methods for describing isolated R. atoms and ions, radiative transitions between highly excited states, and photoionization and photorecombination processes. The authors present a number of efficient methods for describing the structure and properties of R. atoms and calculating processes of collisions with neutral and charged particles as well as spectral-line broadening and shift of Rydberg atomic series in gases, cool and hot plasmas in laboratories and in astrophysical sources. Particular attention is paid to a comparison of theoretical results with available experimental data. The book contains 9 chapters. Chapter 1 gives an introduction to the basic properties of R. atoms (ions), Chapter 2 is devoted to an account of general methods describing an isolated Rydberg atom. Chapter 3 is focussed on the recent achievements in calculations of form factors and dipole matrix elements of different types of bound-bound and bound-free radiative transitions. Chapter 4 concentrates on the formulation of basic theoretical methods and physical approaches to collisions involving R. atoms. Chapters 5 to 8 contain a systematic description of major directions and modern techniques in the collision theory of R. atoms and ions with atoms, molecules, electrons, and ions. Finally, Chapter 9 deals with the spectral-line broadening and shift of R. atomic series induced by collisions with neutral and charged particles. A subject index of four pages and 250 references are given. This monograph will be a basic tool and reference for all scientists working in the fields of plasma physics, spectroscopy, physics of electronic and atomic collisions, as well as astrophysics, radio astronomy, and space physics.

My voice looks like that? A hands-on and textbook free approach to learning physics

NASA Astrophysics Data System (ADS)

Piacsek, Andrew

2009-05-01

Many physics departments offer a ``Physics of Music'' course that is intended for non-majors. This topic appeals to a broad cross-section of students, in part because people recognize that it represents a rare window into the abstruse world of physics from a familiar vantage point. Conversely, physics educators recognize that an interdisciplinary course such as this offers an important opportunity to convey the methods and habits of scientific thinking (let alone some principles of acoustics) to a population that has shunned math and science since high school. In this presentation, I will describe an effective approach to teaching this topic, which has evolved over the past twelve years at Central Washington University. In particular, I will emphasize three elements that distinguish this approach: the sequence of topics, a computer-intensive lab experience, and the use of the internet in lieu of a traditional textbook. The rewards and pitfalls of including small group research projects as part of the class will also be discussed. Information about PHYS103 at CWU can be found at http://www.cwu.edu/˜physics/courses/103/index.html.

Impact of assistive technology on family caregivers of children with physical disabilities: a systematic review.

PubMed

Nicolson, Amy; Moir, Lois; Millsteed, Jeannine

2012-09-01

To systematically review the literature on the effects of assistive technology (AT) on family caregivers of children with physical disabilities. Electronic searches of Medline, CINAHL Plus, PubMed, and PsychInfo were conducted. The main search terms were AT, caregiver, physical disability, cerebral palsy and quality of life. Studies were included if they related to the impact of AT on the family caregiver of children with physical impairment. Data extraction and quality assessments were conducted by three reviewers. Five articles were eligible for inclusion. Two studies rated weak quality of evidence (level 5), two studies rated moderate quality of evidence (level 3), and one article was a systematic review, rating high level of quality (level 1). A paucity of literature, small sample sizes, descriptive study designs and weak methodological quality meant a narrative review was possible. Three articles reported that AT lightened caregiver assistance in the areas of mobility, self- care and social function. Evidence suggests that AT has a positive impact on children with physical impairments and their caregivers. Future studies in this area could include valid and reliable outcome measures of AT use and the psychological impacts of AT on caring for a child with physical impairments.

Parks promoting physical activity: synthesis of findings from interventions in seven national parks.

PubMed

Hoehner, Christine M; Brownson, Ross C; Allen, Diana; Gramann, James; Behrens, Timothy K; Floyd, Myron F; Leahy, Jessica; Liddle, Joseph B; Smaldone, David; Spain, Diara D; Tardona, Daniel R; Ruthmann, Nicholas P; Seiler, Rachel L; Yount, Byron W

2010-03-01

We synthesized the results of 7 National Park Service pilot interventions designed to increase awareness of the health benefits from participation in recreation at national parks and to increase physical activity by park visitors. A content analysis was conducted of the final evaluation reports of the 7 participating parks. Pooled data were also analyzed from a standardized trail-intercept survey administered in 3 parks. The theme of new and diverse partnerships was the most common benefit reported across the 7 sites. The 2 parks that focused on youth showed evidence of an increase in awareness of the benefits of physical activity. Many of the other sites found high levels of awareness at baseline (approaching 90%), suggesting little room for improvement. Five of the 7 projects showed evidence of an increase in physical activity that was associated with the intervention activities. Multivariate analyses suggested that the media exposure contributed to a small but significant increase in awareness of the importance of physical activity (6%) and number of active visits (7%). Enhancements and replication of these programs represents a promising opportunity for improving partnerships between public health and recreation to increase physical activity.

Yoga-based exercise improves balance and mobility in people aged 60 and over: a systematic review and meta-analysis.

PubMed

Youkhana, Sabrina; Dean, Catherine M; Wolff, Moa; Sherrington, Catherine; Tiedemann, Anne

2016-01-01

one-third of community-dwelling older adults fall annually. Exercise that challenges balance is proven to prevent falls. We conducted a systematic review with meta-analysis to determine the impact of yoga-based exercise on balance and physical mobility in people aged 60+ years. searches for relevant trials were conducted on the following electronic databases: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, CINAHL, Allied and Complementary Medicine Database and the Physiotherapy Evidence Database (PEDro) from inception to February 2015. Trials were included if they evaluated the effect of physical yoga (excluding meditation and breathing exercises alone) on balance in people aged 60+ years. We extracted data on balance and the secondary outcome of physical mobility. Standardised mean differences and 95% confidence intervals (CI) were calculated using random-effects models. Methodological quality of trials was assessed using the 10-point Physiotherapy Evidence Database (PEDro) Scale. six trials of relatively high methodological quality, totalling 307 participants, were identified and had data that could be included in a meta-analysis. Overall, yoga interventions had a small effect on balance performance (Hedges' g = 0.40, 95% CI 0.15-0.65, 6 trials) and a medium effect on physical mobility (Hedges' g = 0.50, 95% CI 0.06-0.95, 3 trials). yoga interventions resulted in small improvements in balance and medium improvements in physical mobility in people aged 60+ years. Further research is required to determine whether yoga-related improvements in balance and mobility translate to prevention of falls in older people. PROSPERO Registration number CRD42015015872. © The Author 2015. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Joint observations of solar corona in space projects ARKA and KORTES

NASA Astrophysics Data System (ADS)

Vishnyakov, Eugene A.; Bogachev, Sergey A.; Kirichenko, Alexey S.; Reva, Anton A.; Loboda, Ivan P.; Malyshev, Ilya V.; Ulyanov, Artem S.; Dyatkov, Sergey Yu.; Erkhova, Nataliya F.; Pertsov, Andrei A.; Kuzin, Sergey V.

2017-05-01

ARKA and KORTES are two upcoming solar space missions in extreme ultraviolet and X-ray wavebands. KORTES is a sun-oriented mission designed for the Russian segment of International Space Station. KORTES consists of several imaging and spectroscopic instruments that will observe the solar corona in a number of wavebands, covering EUV and X-ray ranges. The surveillance strategy of KORTES is to cover a wide range of observations including simultaneous imaging, spectroscopic and polarization measurements. ARKA is a small satellite solar mission intended to take highresolution images of the Sun at the extreme ultraviolet wavelengths. ARKA will be equipped with two high-resolution EUV telescopes designed to collect images of the Sun with approximately 150 km spatial resolution in the field of view of about 10'×10'. The scientific results of the mission may have a significant impact on the theory of coronal heating and may help to clarify the physics of small-scale solar structures and phenomena including oscillations of fine coronal structures and the physics of micro- and nanoflares.

Effects of physical and morphometric factors on nutrient removal properties in agricultural ponds.

PubMed

Saito, M; Onodera, S; Okubo, K; Takagi, S; Maruyama, Y; Jin, G; Shimizu, Y

2015-01-01

Effects of physical and morphometric factors on nutrient removal properties were studied in small agricultural ponds with different depths, volumes, and residence times in western Japan. Average residence time was estimated to be >15 days, and it tended to decrease from summer to winter because of the increase in water withdrawal for agricultural activity. Water temperature was clearly different between the surface and bottom layers; this indicates that thermal stratification occurred in summer. Chlorophyll-a was significantly high (>20 μg/L) in the surface layer (<0.5 m) and influenced by the thermal stratification. Removal ratios of dissolved total nitrogen (DTN) and dissolved total phosphorus in the ponds were estimated to be 53-98% and 39-98% in August and 10-92% and 36-57% in December, respectively. Residence time of the ponds was longer in August than in December, and DTN removal, in particular, was more significant in ponds with longer residence time. Our results suggest residence time is an important factor for nitrogen removal in small agricultural ponds as well as large lakes.

Assessment of Student Learning in Modern Experiments in the Introductory Calculus-Based Physics Labs

NASA Astrophysics Data System (ADS)

Woodahl, Brian; Ross, John; Lang, Sarah; Scott, Derek; Williams, Jeremy

2010-10-01

With the advent of newer microelectronic sensors it's now possible to modernize introductory physics labs with the latest technology and this may allow for enhanced student participation/learning in the experiments. For example, force plate sensors can digitize and record the force on an object, later it can be analyzed in detail (i.e, impulse from force vs. time). Small 3-axis accelerometers can record 3-dim, time-dependent acceleration of objects undergoing complex motions. These devices are small, fairly easy to use, and importantly, are likely to enhance student learning by ``personalizing'' data collection, i.e. making the student an active part of the measurement process and no longer a passive observer. To assess whether these new high-tech labs enhance student learning, we have implemented pre- and post- test sessions to measure the effectiveness of student learning. Four of our calculus-based lab sections were used: Two sections the control group, using the previous ``old technology'' labs, the other two, the experimental group, using the new ``modern technology'' labs. Initial returns of assessment data offer some surprising insight.

Quantum indistinguishability in chemical reactions.

PubMed

Fisher, Matthew P A; Radzihovsky, Leo

2018-05-15

Quantum indistinguishability plays a crucial role in many low-energy physical phenomena, from quantum fluids to molecular spectroscopy. It is, however, typically ignored in most high-temperature processes, particularly for ionic coordinates, implicitly assumed to be distinguishable, incoherent, and thus well approximated classically. We explore enzymatic chemical reactions involving small symmetric molecules and argue that in many situations a full quantum treatment of collective nuclear degrees of freedom is essential. Supported by several physical arguments, we conjecture a "quantum dynamical selection" (QDS) rule for small symmetric molecules that precludes chemical processes that involve direct transitions from orbitally nonsymmetric molecular states. As we propose and discuss, the implications of the QDS rule include ( i ) a differential chemical reactivity of para- and orthohydrogen, ( ii ) a mechanism for inducing intermolecular quantum entanglement of nuclear spins, ( iii ) a mass-independent isotope fractionation mechanism, ( iv ) an explanation of the enhanced chemical activity of "reactive oxygen species", ( v ) illuminating the importance of ortho-water molecules in modulating the quantum dynamics of liquid water, and ( vi ) providing the critical quantum-to-biochemical linkage in the nuclear spin model of the (putative) quantum brain, among others.

Precision Determination of the Small-x Gluon from Charm Production at LHCb.

PubMed

Gauld, Rhorry; Rojo, Juan

2017-02-17

The small-x gluon in global fits of parton distributions is affected by large uncertainties from the lack of direct experimental constraints. In this Letter, we provide a precision determination of the small-x gluon from the exploitation of forward charm production data provided by LHCb for three different center-of-mass (c.m.) energies: 5 TeV, 7 TeV, and 13 TeV. The LHCb measurements are included in the parton distribution function (PDF) fit by means of normalized distributions and cross-section ratios between data taken at different c.m. values, R_{13/7} and R_{13/5}. We demonstrate that forward charm production leads to a reduction of the PDF uncertainties of the gluon down to x≃10^{-6} by up to an order of magnitude, with implications for high-energy colliders, cosmic ray physics, and neutrino astronomy.

Using small unmanned aerial vehicle for instream habitat evaluation and modelling

NASA Astrophysics Data System (ADS)

Astegiano, Luca; Vezza, Paolo; Comoglio, Claudio; Lingua, Andrea; Spairani, Michele

2015-04-01

Recent advances in digital image collection and processing have led to the increased use of unmanned aerial vehicles (UAV) for river research and management. In this paper, we assess the capabilities of a small UAV to characterize physical habitat for fish in three river stretches of North-Western Italy. The main aim of the study was identifying the advantages and challenges of this technology for environmental river management, in the context of the increasing river exploitation for hydropower production. The UAV used to acquire overlapping images was a small quadcopter with a two different high-resolution (non-metric) cameras (Nikon J1™ and Go-Pro Hero 3 Black Edition™). The quadcopter was preprogrammed to fly set waypoints using a small tablet PC. With the acquired imagery, we constructed a 5-cm resolution orthomosaic image and a digital surface model (DSM). The two products were used to map the distribution of aquatic and riparian habitat features, i.e., wetted area, morphological unit distributions, bathymetry, water surface gradient, substrates and grain sizes, shelters and cover for fish. The study assessed the quality of collected data and used such information to identify key reach-scale metrics and important aspects of fluvial morphology and aquatic habitat. The potential and limitations of using UAV for physical habitat survey were evaluated and the collected data were used to initialize and run common habitat simulation tools (MesoHABSIM). Several advantages of using UAV-based imagery were found, including low cost procedures, high resolution and efficiency in data collection. However, some challenges were identified for bathymetry extraction (vegetation obstructions, white waters, turbidity) and grain size assessment (preprocessing of data and automatic object detection). The application domain and possible limitation for instream habitat mapping were defined and will be used as a reference for future studies. Ongoing activities include the possibility of using topographic data and discharge measurements to extract average values of flow velocity in cross sections.

Dynamic traversal of high bumps and large gaps by a small legged robot

NASA Astrophysics Data System (ADS)

Gart, Sean; Winey, Nastasia; de La Tijera Obert, Rafael; Li, Chen

Small animals encounter and negotiate diverse obstacles comparable in size or larger than themselves. In recent experiments, we found that cockroaches can dynamically traverse bumps up to 4 times hip height and gaps up to 1 body length. To better understand the physics that governs these locomotor transitions, we studied a small six-legged robot negotiating high bumps and large gaps and compared it to animal observations. We found that the robot was able to traverse bumps as large as 1 hip height and gaps as wide as 0.5 body length. For the bump, the robot often climbed over to traverse when initial body yaw was small, but was often deflected laterally and failed to traverse when initial body yaw was large. A simple locomotion energy landscape model explained these observations. For the gap, traversal probability decreased with gap width, which was well explained by a simple Lagrangian model of a forward-moving rigid body falling over the gap edge. For both the bump and the gap, animal performance far exceeded that of the robot, likely due to their relatively higher running speeds and larger rotational oscillations prior to and during obstacle traversal. Differences between animal and robot obstacle negotiation behaviors revealed that animals used active strategies to overcome potential energy barriers.

High-Intensity Interval Training for Cognitive and Mental Health in Adolescents.

PubMed

Costigan, Sarah A; Eather, Narelle; Plotnikoff, Ronald C; Hillman, Charles H; Lubans, David R

2016-10-01

Emerging literature suggests that physical activity and fitness may have a positive effect on cognitive and mental health in adolescents. The purpose of the current study was to evaluate the efficacy of two high-intensity interval training (HIIT) protocols for improving cognitive and mental health outcomes (executive function, psychological well-being, psychological distress, and physical self-concept) in adolescents. Participants (n = 65; mean age = 15.8 ± 0.6 yr) were randomized to three conditions: aerobic exercise program (AEP; n = 21), resistance and aerobic program (RAP; n = 22), and control (n = 22). HIIT sessions (8-10 min per session) were delivered during physical education lessons or at lunchtime three times per week for 8 wk. Assessments were conducted at baseline and immediately postintervention to detect changes in executive function (trail making test), psychological well-being, psychological distress, and physical self-description by researchers blinded to treatment allocation. Intervention effects were examined using linear mixed models. Cohen's d effect sizes and clinical inference were also calculated. While results were not significant, small improvements in executive function (mean change (95% CI) -6.69 (-22.03, 8.64), d = -0.32) and psychological well-being (mean change (95% CI) 2.81 (-2.06, 7.68), d = 0.34) were evident in the AEP group; and moderate improvements in executive function (mean change (95% CI) -10.73 (-26.22, 4.76), d = -0.51), and small improvements in well-being (mean change (95% CI) 2.96 (-1.82, 7.75), d = 0.36) and perceived appearance (mean change (95% CI) 0.32 (-0.25, 0.86), d = 0.35), were observed for the RAP group. Mean feeling state scores improved from preworkout to postworkout in both HIIT conditions, with significant results for the AEP (P = 0.001). This study highlights the potential of embedding HIIT within the school day for improving cognitive and mental health among adolescents.

The APSU 0.5m Telescope - A Hands-On Learning Environment for Secondary Teachers

NASA Astrophysics Data System (ADS)

Allyn Smith, J.; Buckner, S. L.; Pirkle, S. F.

2012-05-01

Physical science teachers with hands-on experience are critical to secondary education learning. In "Before It’s Too Late," the U.S. Department of Education (2000) estimated "about 56% of high school students taking physical science are taught by out-of-field teachers." In Tennessee, the problem is even greater, while the demand is increasing. This project aims to address the shortage of well-prepared physics and astronomy teachers. Austin Peay State University has recently installed a 0.5m telescope with imaging and rudimentary spectroscopic capability. We are committed to working with the College of Education to bring secondary teachers in training and practicing secondary teachers to the telescope to experience basic operations and conduct small research projects. This is done via classes and summer workshops. We describe the program setup, expectations for the participants, learning outcomes, and the evaluation process.

Physics and evolution of thermophilic adaptation.

PubMed

Berezovsky, Igor N; Shakhnovich, Eugene I

2005-09-06

Analysis of structures and sequences of several hyperthermostable proteins from various sources reveals two major physical mechanisms of their thermostabilization. The first mechanism is "structure-based," whereby some hyperthermostable proteins are significantly more compact than their mesophilic homologues, while no particular interaction type appears to cause stabilization; rather, a sheer number of interactions is responsible for thermostability. Other hyperthermostable proteins employ an alternative, "sequence-based" mechanism of their thermal stabilization. They do not show pronounced structural differences from mesophilic homologues. Rather, a small number of apparently strong interactions is responsible for high thermal stability of these proteins. High-throughput comparative analysis of structures and complete genomes of several hyperthermophilic archaea and bacteria revealed that organisms develop diverse strategies of thermophilic adaptation by using, to a varying degree, two fundamental physical mechanisms of thermostability. The choice of a particular strategy depends on the evolutionary history of an organism. Proteins from organisms that originated in an extreme environment, such as hyperthermophilic archaea (Pyrococcus furiosus), are significantly more compact and more hydrophobic than their mesophilic counterparts. Alternatively, organisms that evolved as mesophiles but later recolonized a hot environment (Thermotoga maritima) relied in their evolutionary strategy of thermophilic adaptation on "sequence-based" mechanism of thermostability. We propose an evolutionary explanation of these differences based on physical concepts of protein designability.

13 CFR 123.201 - When am I not eligible to apply for a physical disaster business loan?

Code of Federal Regulations, 2013 CFR

2013-01-01

... for a physical disaster business loan? 123.201 Section 123.201 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.201 When am I not eligible to apply for a physical disaster business loan? (a) You are not eligible for a physical disaster...

13 CFR 123.201 - When am I not eligible to apply for a physical disaster business loan?

Code of Federal Regulations, 2014 CFR

2014-01-01

... for a physical disaster business loan? 123.201 Section 123.201 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.201 When am I not eligible to apply for a physical disaster business loan? (a) You are not eligible for a physical disaster...

13 CFR 123.201 - When am I not eligible to apply for a physical disaster business loan?

Code of Federal Regulations, 2012 CFR

2012-01-01

... for a physical disaster business loan? 123.201 Section 123.201 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.201 When am I not eligible to apply for a physical disaster business loan? (a) You are not eligible for a physical disaster...

Effects of Dietary Conjugated Linoleic Acid and Biopolymer Encapsulation on Lipid Metabolism in Mice

PubMed Central

Hur, Sun Jin; Kim, Doo Hwan; Chun, Se Chul; Lee, Si Kyung

2013-01-01

Forty mice were randomly divided into four groups on the basis of the diet to be fed as follows: 5% (low) fat diet (T1: LF); 20% (high) fat diet (T2: HF); 20% fat containing 1% conjugated linoleic acid (CLA) (T3: HFC); and 20% fat containing 1% CLA with 0.5% biopolymers (T4: HFCB). The high-fat with CLA diet groups (HFC and HFCB) and the low-fat diet group (LF) tended to have lower body weights and total adipose tissue weights than those of the high-fat diet group (HF). Serum leptin and triglyceride were significantly lower in the high fat with CLA-fed groups (HFC and HFCB) and the low-fat diet group (LF) than those in the high-fat diet group (HF). It is noteworthy that the high-fat with CLA and biopolymers group (HFCB) showed the lowest serum triglyceride and cholesterol concentrations. In the high-fat-fed group (HF), voluntary travel distance as a measure of physical activity decreased after three weeks of feeding. However, the CLA-fed groups showed increased physical activity. The groups fed high-fat diets supplemented with CLA alone and with CLA and biopolymers had higher viscosity of small intestinal contents than that in the low- and high-fat dietary groups. PMID:23531540

Role of physical and mental training in brain network configuration

PubMed Central

Foster, Philip P.

2015-01-01

It is hypothesized that the topology of brain networks is constructed by connecting nodes which may be continuously remodeled by appropriate training. Efficiency of physical and/or mental training on the brain relies on the flexibility of networks' architecture molded by local remodeling of proteins and synapses of excitatory neurons producing transformations in network topology. Continuous remodeling of proteins of excitatory neurons is fine-tuning the scaling and strength of excitatory synapses up or down via regulation of intra-cellular metabolic and regulatory networks of the genome-transcriptome-proteome interface. Alzheimer's disease is a model of “energy cost-driven small-world network disorder” with dysfunction of high-energy cost wiring as the network global efficiency is impaired by the deposition of an informed agent, the amyloid-β, selectively targeting high-degree nodes. In schizophrenia, the interconnectivity and density of rich-club networks are significantly reduced. Training-induced homeostatic synaptogenesis-enhancement, presumably via reconfiguration of brain networks into greater small-worldness, appears essential in learning, memory, and executive functions. A macroscopic cartography of creation-removal of synaptic connections in a macro-network, and at the intra-cellular scale, micro-networks regulate the physiological mechanisms for the preferential attachment of synapses. The strongest molecular relationship of exercise and functional connectivity was identified for brain-derived neurotrophic factor (BDNF). The allele variant, rs7294919, also shows a powerful relationship with the hippocampal volume. How the brain achieves this unique quest of reconfiguration remains a puzzle. What are the underlying mechanisms of synaptogenesis promoting communications brain ↔ muscle and brain ↔ brain in such trainings? What is the respective role of independent mental, physical, or combined-mental-physical trainings? Physical practice seems to be playing an instrumental role in the cognitive enhancement (brain ↔ muscle com.). However, mental training, meditation or virtual reality (films, games) require only minimal motor activity and cardio-respiratory stimulation. Therefore, other potential paths (brain ↔ brain com.) molding brain networks are nonetheless essential. Patients with motor neuron disease/injury (e.g., amyotrophic lateral sclerosis, traumatism) also achieve successful cognitive enhancement albeit they may only elicit mental practice. PMID:26157387

Role of physical and mental training in brain network configuration.

PubMed

Foster, Philip P

2015-01-01

It is hypothesized that the topology of brain networks is constructed by connecting nodes which may be continuously remodeled by appropriate training. Efficiency of physical and/or mental training on the brain relies on the flexibility of networks' architecture molded by local remodeling of proteins and synapses of excitatory neurons producing transformations in network topology. Continuous remodeling of proteins of excitatory neurons is fine-tuning the scaling and strength of excitatory synapses up or down via regulation of intra-cellular metabolic and regulatory networks of the genome-transcriptome-proteome interface. Alzheimer's disease is a model of "energy cost-driven small-world network disorder" with dysfunction of high-energy cost wiring as the network global efficiency is impaired by the deposition of an informed agent, the amyloid-β, selectively targeting high-degree nodes. In schizophrenia, the interconnectivity and density of rich-club networks are significantly reduced. Training-induced homeostatic synaptogenesis-enhancement, presumably via reconfiguration of brain networks into greater small-worldness, appears essential in learning, memory, and executive functions. A macroscopic cartography of creation-removal of synaptic connections in a macro-network, and at the intra-cellular scale, micro-networks regulate the physiological mechanisms for the preferential attachment of synapses. The strongest molecular relationship of exercise and functional connectivity was identified for brain-derived neurotrophic factor (BDNF). The allele variant, rs7294919, also shows a powerful relationship with the hippocampal volume. How the brain achieves this unique quest of reconfiguration remains a puzzle. What are the underlying mechanisms of synaptogenesis promoting communications brain ↔ muscle and brain ↔ brain in such trainings? What is the respective role of independent mental, physical, or combined-mental-physical trainings? Physical practice seems to be playing an instrumental role in the cognitive enhancement (brain ↔ muscle com.). However, mental training, meditation or virtual reality (films, games) require only minimal motor activity and cardio-respiratory stimulation. Therefore, other potential paths (brain ↔ brain com.) molding brain networks are nonetheless essential. Patients with motor neuron disease/injury (e.g., amyotrophic lateral sclerosis, traumatism) also achieve successful cognitive enhancement albeit they may only elicit mental practice.

Hillslope Evolution by Bedrock Landslides

PubMed

Densmore; Anderson; McAdoo; Ellis

1997-01-17

Bedrock landsliding is a dominant geomorphic process in a number of high-relief landscapes, yet is neglected in landscape evolution models. A physical model of sliding in beans is presented, in which incremental lowering of one wall simulates baselevel fall and generates slides. Frequent small slides produce irregular hillslopes, on which steep toes and head scarps persist until being cleared by infrequent large slides. These steep segments are observed on hillslopes in high-relief landscapes and have been interpreted as evidence for increases in tectonic or climatic process rates. In certain cases, they may instead reflect normal hillslope evolution by landsliding.

Solar powered blackbody-pumped lasers

NASA Astrophysics Data System (ADS)

Christiansen, Walter H.; Sirota, J. M.

1991-02-01

A concept for a solar-powered laser is presented which utilizes an intermediate blackbody cavity to provide a uniform optical pumping environment for the lasant, typically CO or CO2 or possibly a solid state laser medium. High power cw blackbody- pumped lasers with efficiencies on the order of 20 percent or more are feasible. The physical basis of this idea is reviewed. Small scale experiments using a high temperature oven as the optical pump have been carried out with gas laser mixtures. Detailed calculations showing a potential efficiency of 35 percent for blackbody pumped Nd:YAG system are discussed.

[Physical activity for young adults born with low body weight on the background of peers].

PubMed

Tkaczyk, Joanna; Kęska, Anna; Czajkowska, Anna; Wiśniewski, Andrzej

2010-01-01

Low birth parameters are associated with an increased risk of insulin resistance, type 2 diabetes, glucose intolerance and hypertension at later life. Regular physical activity can counteract these metabolic disorders. We determined the relation of the declared physical activity and body composition in young adults with respect to their birth weight. A total of 156 subjects (52% women and 48% men) took part in the study (the average age 20.6±1.2 years). Participants who declared regular physical activity (minimum 3 times per week) were included in group I (n=66), others in group II (n=99). In each group, the percentage of people with small (SBW) and normal (NBW) birth weight was assessed. Information about birth parameters and duration of pregnancy was obtained from medical records. Infant's mass ≤2999 g was recognized as small birth weight. Body height, body weight, waist and hips circumferences and body composition by BIA were measured. Frequency of physical activity was determined during an interview. Percentage of participants with small birth weight was respectively 17% in group I and 21% in group II. In group I standardized body height was significantly lower in subjects with SBW in comparison with those with NBW. Participants from group II with SBW had markedly lower standardized body weight and standardized BMI than adults with NBW. Independently of birth weight physically active persons characterized higher WHR values than their non active counterparts. Body fat content was significantly lower in group I (both in participants with SBW and NBW). Women and men from group I with SBW had also higher fat free mass in comparison with those from group II. Body fat content in young adults with small birth weight is related to their physical activity. People who regularly exercise had lower fat mass in comparison with non exercising ones. This is the confirmation of a protective influence of physical activity.

Global Advocacy for Physical Activity (GAPA): global leadership towards a raised profile.

PubMed

Blanchard, Claire; Shilton, Trevor; Bull, Fiona

2013-12-01

Physical inactivity has been recognised by the World Health Organization as one of the leading causes of death due to non-communicable disease (NCD), worldwide. The benefits of action over inactivity can cut across health, environment, transportation, sport, culture and the economy. Despite the evidence, the policies and strategies to increase population-wide participation in physical activity receive insufficient priority from across high, middle and low-income countries; where physical inactivity is a rapidly-emerging issue. There is an increased need for all countries to invest in policies, strategies and supportive environments that inform, motivate and support individuals and communities to be active in ways that are safe, accessible and enjoyable. This commentary presents some recent efforts towards physical activity promotion globally, led by the Global Advocacy for Physical Activity (GAPA). It provides an overview of the background and history of GAPA; describes GAPA and the council's key achievements and milestones; places physical activity promotion within the global NCD agenda; presents GAPA flagships; and reflects on the lessons learned, ingredients for success and the major challenges that remain. The commentary documents insights into the effectiveness and challenges faced by a small non-governmental organisation (NGO) in mounting global advocacy. These lessons may be transferrable to other areas of health promotion advocacy.

CONFERENCE REPORT: Summary of the 16th IAEA Technical Meeting on 'Research using Small Fusion Devices'

NASA Astrophysics Data System (ADS)

Gribkov, V.; Van Oost, G.; Malaquias, A.; Herrera, J.

2006-10-01

Common research topics that are being studied in small, medium and large devices such as H-mode like or improved confinement, turbulence and transport are reported. These included modelling and diagnostic developments for edge and core, to characterize plasma density, temperature, electric potential, plasma flows, turbulence scale, etc. Innovative diagnostic methods were designed and implemented which could be used to develop experiments in small devices (in some cases not possible in large devices due to higher power deposition) to allow a better understanding of plasma edge and core properties. Reports are given addressing research in linear devices that can be used to study particular plasma physics topics relevant for other magnetic confinement devices such as the radial transport and the modelling of self-organized plasma jets involved in spheromak-like plasma formation. Some aspects of the work presented are of interest to the astrophysics community since they are believed to shed light on the basis of the physics of stellar jets. On the dense magnetized plasmas (DMP) topic, the present status of research, operation of new devices, plasma dynamics modelling and diagnostic developments is reported. The main devices presented belong to the class of Z-pinches, mostly plasma foci, and several papers were presented under this topic. The physics of DMP is important both for the main-stream fusion investigations as well as for providing the basis for elaboration of new concepts. New high-current technology introduced in the DMP devices design and construction make these devices nowadays more reliably fitted to various applications and give the possibility to widen the energy range used by them in both directions—to the multi-MJ level facilities and down to miniature plasma focus devices with energy of just a few J.

Parallelized Kalman-Filter-Based Reconstruction of Particle Tracks on Many-Core Architectures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cerati, Giuseppe; Elmer, Peter; Krutelyov, Slava

Faced with physical and energy density limitations on clock speed, contemporary microprocessor designers have increasingly turned to on-chip parallelism for performance gains. Examples include the Intel Xeon Phi, GPGPUs, and similar technologies. Algorithms should accordingly be designed with ample amounts of fine-grained parallelism if they are to realize the full performance of the hardware. This requirement can be challenging for algorithms that are naturally expressed as a sequence of small-matrix operations, such as the Kalman filter methods widely in use in high-energy physics experiments. In the High-Luminosity Large Hadron Collider (HL-LHC), for example, one of the dominant computational problems ismore » expected to be finding and fitting charged-particle tracks during event reconstruction; today, the most common track-finding methods are those based on the Kalman filter. Experience at the LHC, both in the trigger and offline, has shown that these methods are robust and provide high physics performance. Previously we reported the significant parallel speedups that resulted from our efforts to adapt Kalman-filter-based tracking to many-core architectures such as Intel Xeon Phi. Here we report on how effectively those techniques can be applied to more realistic detector configurations and event complexity.« less

Adolescent Self-Reported Physical Activity and Autonomy: A Case for Constrained and Structured Environments?

PubMed

Rachele, Jerome N; Jaakkola, Timo; Washington, Tracy L; Cuddihy, Thomas F; McPhail, Steven M

2015-09-01

The provision of autonomy supportive environments that promote physical activity engagement have become popular in contemporary youth settings. However, questions remain about whether adolescent perceptions of their autonomy have implications for physical activity. The purpose of this investigation was to examine the association between adolescents' self-reported physical activity and their perceived autonomy. Participants (n = 384 adolescents) aged between 12 and 15 years were recruited from six secondary schools in metropolitan Brisbane, Australia. Self-reported measures of physical activity and autonomy were obtained. Logistic regression with inverse probability weights were used to examine the association between autonomy and the odds of meeting youth physical activity guidelines. Autonomy (OR 0.61, 95% CI 0.49-0.76) and gender (OR 0.62, 95% CI 0.46-0.83) were negatively associated with meeting physical activity guidelines. However, the model explained only a small amount of the variation in whether youth in this sample met physical activity guidelines (R(2) = 0.023). For every 1 unit decrease in autonomy (on an index from 1 to 5), participants were 1.64 times more likely to meet physical activity guidelines. The findings, which are at odds with several previous studies, suggest that interventions designed to facilitate youth physical activity should limit opportunities for youth to make independent decisions about their engagement. However, the small amount of variation explained by the predictors in the model is a caveat, and should be considered prior to applying such suggestions in practical settings. Future research should continue to examine a larger age range, longitudinal observational or intervention studies to examine assertions of causality, as well as objective measurement of physical activity. Key pointsAutonomy was negatively associated with meeting physical activity recommendationsThe findings suggest that more structured environments would facilitate physical activityThe small amount of variation explained by the predictors in the model is a caveat.

Effectiveness of a worksite social & physical environment intervention on need for recovery, physical activity and relaxation; results of a randomized controlled trial.

PubMed

Coffeng, Jennifer K; Boot, Cécile R L; Duijts, Saskia F A; Twisk, Jos W R; van Mechelen, Willem; Hendriksen, Ingrid J M

2014-01-01

To investigate the effectiveness of a worksite social and physical environment intervention on need for recovery (i.e., early symptoms of work-related mental and physical fatigue), physical activity and relaxation. Also, the effectiveness of the separate interventions was investigated. In this 2 × 2 factorial design study, 412 office employees from a financial service provider participated. Participants were allocated to the combined social and physical intervention, to the social intervention only, to the physical intervention only or to the control group. The primary outcome measure was need for recovery. Secondary outcomes were work-related stress (i.e., exhaustion, detachment and relaxation), small breaks, physical activity (i.e., stair climbing, active commuting, sport activities, light/moderate/vigorous physical activity) and sedentary behavior. Outcomes were measured by questionnaires at baseline, 6 and 12 months follow-up. Multilevel analyses were performed to investigate the effects of the three interventions. In all intervention groups, a non-significant reduction was found in need for recovery. In the combined intervention (n = 92), exhaustion and vigorous physical activities decreased significantly, and small breaks at work and active commuting increased significantly compared to the control group. The social intervention (n = 118) showed a significant reduction in exhaustion, sedentary behavior at work and a significant increase in small breaks at work and leisure activities. In the physical intervention (n = 96), stair climbing at work and active commuting significantly increased, and sedentary behavior at work decreased significantly compared to the control group. None of the interventions was effective in improving the need for recovery. It is recommended to implement the social and physical intervention among a population with higher baseline values of need for recovery. Furthermore, the intervention itself could be improved by increasing the intensity of the intervention (for example weekly GMI-sessions), providing physical activity opportunities and exercise schemes, and by more drastic environment interventions (restructuring entire department floor). Nederlands Trial Register NTR2553.

The 'right' size in nanobiotechnology.

PubMed

Whitesides, George M

2003-10-01

The biological and physical sciences share a common interest in small structures (the definition of 'small' depends on the application, but can range from 1 nm to 1 mm). A vigorous trade across the borders of these areas of science is developing around new materials and tools (largely from the physical sciences) and new phenomena (largely from the biological sciences). The physical sciences offer tools for synthesis and fabrication of devices for measuring the characteristics of cells and sub-cellular components, and of materials useful in cell and molecular biology; biology offers a window into the most sophisticated collection of functional nanostructures that exists.

Atomistic modelling of scattering data in the Collaborative Computational Project for Small Angle Scattering (CCP-SAS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Perkins, Stephen J.; Wright, David W.; Zhang, Hailiang

2016-10-14

The capabilities of current computer simulations provide a unique opportunity to model small-angle scattering (SAS) data at the atomistic level, and to include other structural constraints ranging from molecular and atomistic energetics to crystallography, electron microscopy and NMR. This extends the capabilities of solution scattering and provides deeper insights into the physics and chemistry of the systems studied. Realizing this potential, however, requires integrating the experimental data with a new generation of modelling software. To achieve this, the CCP-SAS collaboration (http://www.ccpsas.org/) is developing open-source, high-throughput and user-friendly software for the atomistic and coarse-grained molecular modelling of scattering data. Robust state-of-the-artmore » molecular simulation engines and molecular dynamics and Monte Carlo force fields provide constraints to the solution structure inferred from the small-angle scattering data, which incorporates the known physical chemistry of the system. The implementation of this software suite involves a tiered approach in whichGenAppprovides the deployment infrastructure for running applications on both standard and high-performance computing hardware, andSASSIEprovides a workflow framework into which modules can be plugged to prepare structures, carry out simulations, calculate theoretical scattering data and compare results with experimental data.GenAppproduces the accessible web-based front end termedSASSIE-web, andGenAppandSASSIEalso make community SAS codes available. Applications are illustrated by case studies: (i) inter-domain flexibility in two- to six-domain proteins as exemplified by HIV-1 Gag, MASP and ubiquitin; (ii) the hinge conformation in human IgG2 and IgA1 antibodies; (iii) the complex formed between a hexameric protein Hfq and mRNA; and (iv) synthetic `bottlebrush' polymers.« less

Dosimetry in small-animal CT using Monte Carlo simulations

NASA Astrophysics Data System (ADS)

Lee, C.-L.; Park, S.-J.; Jeon, P.-H.; Jo, B.-D.; Kim, H.-J.

2016-01-01

Small-animal computed tomography (micro-CT) imaging devices are increasingly being used in biological research. While investigators are mainly interested in high-contrast, low-noise, and high-resolution anatomical images, relatively large radiation doses are required, and there is also growing concern over the radiological risk from preclinical experiments. This study was conducted to determine the radiation dose in a mouse model for dosimetric estimates using the GEANT4 application for tomographic emission simulations (GATE) and to extend its techniques to various small-animal CT applications. Radiation dose simulations were performed with the same parameters as those for the measured micro-CT data, using the MOBY phantom, a pencil ion chamber and an electrometer with a CT detector. For physical validation of radiation dose, absorbed dose of brain and liver in mouse were evaluated to compare simulated results with physically measured data using thermoluminescent dosimeters (TLDs). The mean difference between simulated and measured data was less than 2.9% at 50 kVp X-ray source. The absorbed doses of 37 brain tissues and major organs of the mouse were evaluated according to kVp changes. The absorbed dose over all of the measurements in the brain (37 types of tissues) consistently increased and ranged from 42.4 to 104.0 mGy. Among the brain tissues, the absorbed dose of the hypothalamus (157.8-414.30 mGy) was the highest for the beams at 50-80 kVp, and that of the corpus callosum (11.2-26.6 mGy) was the lowest. These results can be used as a dosimetric database to control mouse doses and preclinical targeted radiotherapy experiments. In addition, to accurately calculate the mouse-absorbed dose, the X-ray spectrum, detector alignment, and uncertainty in the elemental composition of the simulated materials must be accurately modeled.

Atomistic modelling of scattering data in the Collaborative Computational Project for Small Angle Scattering (CCP-SAS).

PubMed

Perkins, Stephen J; Wright, David W; Zhang, Hailiang; Brookes, Emre H; Chen, Jianhan; Irving, Thomas C; Krueger, Susan; Barlow, David J; Edler, Karen J; Scott, David J; Terrill, Nicholas J; King, Stephen M; Butler, Paul D; Curtis, Joseph E

2016-12-01

The capabilities of current computer simulations provide a unique opportunity to model small-angle scattering (SAS) data at the atomistic level, and to include other structural constraints ranging from molecular and atomistic energetics to crystallography, electron microscopy and NMR. This extends the capabilities of solution scattering and provides deeper insights into the physics and chemistry of the systems studied. Realizing this potential, however, requires integrating the experimental data with a new generation of modelling software. To achieve this, the CCP-SAS collaboration (http://www.ccpsas.org/) is developing open-source, high-throughput and user-friendly software for the atomistic and coarse-grained molecular modelling of scattering data. Robust state-of-the-art molecular simulation engines and molecular dynamics and Monte Carlo force fields provide constraints to the solution structure inferred from the small-angle scattering data, which incorporates the known physical chemistry of the system. The implementation of this software suite involves a tiered approach in which GenApp provides the deployment infrastructure for running applications on both standard and high-performance computing hardware, and SASSIE provides a workflow framework into which modules can be plugged to prepare structures, carry out simulations, calculate theoretical scattering data and compare results with experimental data. GenApp produces the accessible web-based front end termed SASSIE-web , and GenApp and SASSIE also make community SAS codes available. Applications are illustrated by case studies: (i) inter-domain flexibility in two- to six-domain proteins as exemplified by HIV-1 Gag, MASP and ubiquitin; (ii) the hinge conformation in human IgG2 and IgA1 antibodies; (iii) the complex formed between a hexameric protein Hfq and mRNA; and (iv) synthetic 'bottlebrush' polymers.

Resolving the Small-Scale Structure of the Circumgalactic Medium in Cosmological Simulations

NASA Astrophysics Data System (ADS)

Corlies, Lauren

2017-08-01

We propose to resolve the circumgalactic medium (CGM) of L* galaxies down to 100 Msun (250 pc) in a full cosmological simulation to examine how mixing and cooling shape the physical nature of this gas on the scales expected from observations. COS has provided the best characterization of the low-z CGM to date, revealing the extent and amount of low- and high-ions and hinting at the kinematic relations between them. Yet cosmological galaxy simulations that can reproduce the stellar properties of galaxies have all struggled to reproduce these results even qualitatively. However, while the COS data imply that the low-ion absorption is occurring on sub-kpc scales, such scales can not be traced by simulations with resolution between 1-5 kpc in the CGM. Our proposed simulations will, for the first time, reach the resolution required to resolve these structures in the outer halo of L* galaxies. Using the adaptive mesh refinement code enzo, we will experiment with the size, shape, and resolution of an enforced high refinement region extending from the disk into the CGM to identify the best configuration for probing the flows of gas throughout the CGM. Our test case has found that increasing the resolution alone can have dramatic consequences for the density, temperature, and kinematics along a line of sight. Coupling this technique with an independent feedback study already underway will help disentangle the roles of global and small scale physics in setting the physical state of the CGM. Finally, we will use the MISTY pipeline to generate realistic mock spectra for direct comparison with COS data which will be made available through MAST.

Formulation and shelf life stability of water-borne lecithin nanoparticles for potential application in dietary supplements field.

PubMed

Edris, Amr E

2012-09-01

ABSTRACT The objective of the present investigation is to formulate commercial soybean lecithin as nanoparticles in solvent-free aqueous system for potential supplementary applications. A mechanical method, which involved two major steps, was used for that purpose. First, lecithin submicron particles (~ 0.5 μm) have been prepared by gradual hydration of lecithin powder using mechanical agitation. Finally, the size of these particles was further reduced to < 100 nm by using high-pressure microfluidization. The physical stability (appearance, particle size distribution, ζ-potential) and the chemical stability (lipid oxidation) of the dispersions carrying lecithin nanoparticles were assessed every 15 days during the 3-month shelf life period at two different temperatures. Results showed that the final particle size of lecithin in the freshly prepared aqueous dispersion was 79.8 ± 1.0 nm and the amount of peroxide detected was 3.5 ± 0.2 meq/kg lipid. At the end of the storage period, dispersions stored at 4°C exhibited physical and chemical stability as evident from the translucent appearance, the small change in particle size (84.1 ± 1.3 nm), and the small amount of generated peroxides (4.1 ± 0.2 meq/kg lipid). On the other hand, dispersions stored at 25°C were physically stable up to 60 days. Over that period, samples became turbid and the particle size increased to 145.0 ± 1.7 nm with a bimodal distribution pattern. This behavior was due to phospholipids (PLs) degradation and hydrolysis under acidic conditions, which proceeds faster at a relatively high temperature (25°C) than at (4°C). The outcome of this investigation may help in developing water-based dispersions carrying lecithin nanoparticles for dietary supplement of PLs.

Inertial electrostatic confinement as a power source for electric propulsion

NASA Technical Reports Server (NTRS)

Miley, G. H.; Burton, R.; Javedani, J.; Yamamoto, Y.; Satsangi, A; Gu, Y.; Heck, P.; Nebel, R.; Schulze, N.; Christensen, J.

1993-01-01

The potential use of an INERTIAL ELECTROSTATIC CONFINEMENT (IEC) power source for space propulsion has previously been suggested by the authors and others. In the past, these discussions have generally followed the charged-particle electric-discharge engine (QED) concept proposed by Bussard, in which the IEC is used to generate an electron beam which vaporizes liquid hydrogen for use as a propellant. However, an alternate approach is considered, using the IEC to drive a 'conventional' electric thruster unit. This has the advantage of building on the rapidly developing technology for such thrusters, which operate at higher specific impulse. Key issues related to this approach include the continued successful development of the physics and engineering of the IEC unit, as well as the development of efficient step-down dc voltage transformers. The IEC operates by radial injection of energetic ions into a spherical vessel. A very high ion density is created in a small core region at the center of the vessel, resulting in extremely high fusion power density in the core. Experiments at the U. of Illinois in small IEC devices (is less than 60 cm. dia.) demonstrated much of the basic physics underlying this concept, e.g. producing 10(exp 6) D-D neutrons/sec steady-state with deuterium gas flow injection. The ultimate goal is to increase the power densities by several orders of magnitude and to convert to D-He-3 injection. If successful, such an experiment would represent a milestone proof-of-principle device for eventual space power use. Further discussion of IEC physics and status are presented with a description of the overall propulsion system and estimated performance.

Inertial electrostatic confinement as a power source for electric propulsion

NASA Technical Reports Server (NTRS)

Miley, George H.; Burton, R.; Javedani, J.; Yamamoto, Y.; Satsangi, A.; Gu, Y.; Heck, P.; Nebel, R.; Schulze, N.; Christensen, J.

1993-01-01

The potential use of an Inertial Electrostatic Confinement (IEC) power source for space propulsion has previously been suggested by the authors and others. In the past, these discussions have generally followed the charged-particle electric-discharge engine (QED) concept proposed by Bussard, in which the IEC is used to generate an electron beam which vaporizes liquid hydrogen for use as a propellant. However, in the present study, we consider an alternate approach, using the IEC to drive a conventional electric thruster unit. This has the advantage of building on the rapidly developing technology for such thrusters, which operate at higher specific impulse. Key issues related to this approach include the continued successful development of the physics and engineering of the IEC unit, as well as the development of efficient step-down dc voltage transformers. The IEC operates by radial injection of energetic ions into a spherical vessel. A very high ion density is created in a small core region at the center of the vessel, resulting in extremely high fusion power density in the core. Present experiments at the U. of Illinois in small IEC devices (less than 60-cm. dia.) have demonstrated much of the basic physics underlying this concept, e.g. producing approximately 10(exp 6) D-D neutrons/sec steady-state with deuterium gas flow injection. The ultimate goal is to increase the power densities by several orders of magnitude and to convert to D-He-3 injection. If successful, such an experiment would represent a milestone proof-of-principle device for eventual space power use. Further discussion of IEC physics and status will be presented with a description of the overall propulsion system and estimated performance.

Biological-Physical Feedbacks Determine Coastal Environmental Response to Climate Change

NASA Astrophysics Data System (ADS)

Moore, L. J.; Duran Vinent, O.; Walters, D.; Fagherazzi, S.; Mariotti, G.; Young, D.; Wolner, C. V.

2012-12-01

As low-lying coastal landforms, transitional between marine and terrestrial realms, barrier islands are especially sensitive to changing environmental conditions. Interactions among biological and physical processes appear to play a critical role in determining how these landscapes will evolve in the future as sea level rises, storm intensity increases and plant species composition changes. Within a new conceptual framework, barrier islands tend to exist in one of two primary states. "Low" islands have little relief above sea level and are dominated by external processes, responding quickly on short time scales to changes in forcing (e.g., storms, sea level rise, etc.), migrating rapidly and generally being low in ecological diversity and productivity. In contrast, "high" islands are less vulnerable to storms, tend to be dominated by internal processes (e.g., sand trapping by vegetation), require long time periods to respond to changes in forcing, migrate slowly (if at all) and host a range of plant species and morphological environments including shrubs, small trees and vegetated secondary and tertiary dunes with intervening swales. The continued existence of barrier island landforms will depend on the degree to which islands can maintain elevation above sea level while also responding to changes in forcing by migrating landward. A long-term morphological-behavior model exploring coupled barrier-marsh evolution and a new ecomorphodynamic model representing the formation/recovery of dunes as a function of storms, shed light on the role of interactions among biological and physical processes on barrier island response to climate change. Results suggest that connections between the marsh and barrier realms, which are mediated by biological processes in the marsh environment, are highly sensitive to factors such as sea level rise rate, antecedent morphology and marsh composition. Results also suggest that feedbacks between sediment transport and vegetation involved in dune building may allow small, gradual changes in storms to cause abrupt, nonlinear transitions from the high to low island state.

Relationships among measures of physical activity and hearing in African Americans: The Jackson Heart Study.

PubMed

Haas, Patrick J; Bishop, Charles E; Gao, Yan; Griswold, Michael E; Schweinfurth, John M

2016-10-01

To evaluate the relationships among measures of physical activity and hearing in the Jackson Heart Study. Prospective cohort study. We assessed hearing on 1,221 Jackson Heart Study participants who also had validated physical activity questionnaire data on file. Hearing thresholds were measured across frequency octaves from 250 to 8,000 Hz, and various frequency pure-tone averages (PTAs) were constructed, including PTA4 (average of 500, 1,000, 2,000, and 4,000 Hz), PTA-high (average of 4,000 and 8,000 Hz), PTA-mid (average of 1,000 and 2,000 Hz), and PTA-low (average of 250 and 500 Hz). Hearing loss was defined for pure tones and pure-tone averages as >25 dB HL in either ear and averaged between the ears. Associations between physical activity and hearing were estimated using linear regression, reporting changes in decibel hearing level, and logistic regression, reporting odds ratios (OR) of hearing loss. Physical activity exhibited a statistically significant but small inverse relationship with PTA4, -0.20 dB HL per doubling of activity (95% confidence interval [CI]: -0.35, -0.04; P = .016), as well as with PTA-low and pure tones at 250, 2,000, and 4,000 Hz in adjusted models. Multivariable logistic regression modeling supported a decrease in the odds of high-frequency hearing loss among participants who reported at least some moderate weekly physical activity (PTA-high, OR: 0.69 [95% CI: 0.52, 0.92]; P = .011 and 4000 Hz, OR: 0.75 [95% CI: 0.57, 0.99]; P = .044). Our study provides further evidence that physical activity is related to better hearing; however, the clinical significance of this relationship cannot be estimated given the nature of the cross-sectional study design. 2b Laryngoscope, 126:2376-2381, 2016. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

The Small Body Mapping Tool (SBMT) for Accessing, Visualizing, and Analyzing Spacecraft Data in Three Dimensions

NASA Astrophysics Data System (ADS)

Barnouin, O. S.; Ernst, C. M.; Daly, R. T.

2018-04-01

The free, publicly available Small Body Mapping Tool (SBMT) developed at the Johns Hopkins University Applied Physics Laboratory is a powerful, easy-to-use tool for accessing and analyzing data from small bodies.

75 FR 10223 - Procurement List Proposed Additions and Deletions

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-05

... Uniform, T-Shirts X Small to XXX Large NSN: 8465-00-NIB-0189--XSmall NSN: 8465-00-NIB-0190--Small NSN..., AR Coast Guard Physical Fitness Uniform, Trunks X Small to XXX Large NSN: 8465-00-NIB-0196--XSmall...

Extracting the distribution of laser damage precursors on fused silica surfaces for 351 nm, 3 ns laser pulses at high fluences (20-150 J/cm2).

PubMed

Laurence, Ted A; Bude, Jeff D; Ly, Sonny; Shen, Nan; Feit, Michael D

2012-05-07

Surface laser damage limits the lifetime of optics for systems guiding high fluence pulses, particularly damage in silica optics used for inertial confinement fusion-class lasers (nanosecond-scale high energy pulses at 355 nm/3.5 eV). The density of damage precursors at low fluence has been measured using large beams (1-3 cm); higher fluences cannot be measured easily since the high density of resulting damage initiation sites results in clustering. We developed automated experiments and analysis that allow us to damage test thousands of sites with small beams (10-30 µm), and automatically image the test sites to determine if laser damage occurred. We developed an analysis method that provides a rigorous connection between these small beam damage test results of damage probability versus laser pulse energy and the large beam damage results of damage precursor densities versus fluence. We find that for uncoated and coated fused silica samples, the distribution of precursors nearly flattens at very high fluences, up to 150 J/cm2, providing important constraints on the physical distribution and nature of these precursors.

Design of Quantum Algorithms Using Physics Tools

DTIC Science & Technology

2014-06-02

invariant spin-1 chain that has a unique highly entangled ground state and exhibits some signatures of critical behavior. The entanglement entropy of one... entangled and found them hard to approximate using the MPS method. In follow on work Shor along with Sergey Bravyi, Libor Caha, Movassagh and Nagaj...They asked how entangled the ground state of a FF quantum spin-s chain with nearest-neighbor interactions can be for small values of s. While FF spin-1

Development of compact particle detectors for space based instruments

NASA Astrophysics Data System (ADS)

Barner, Lindsey; Grove, Andrew; Mohler, Jacob; Sisson, Caleb; Roth, Alex; Kryemadhi, Abaz

2017-01-01

The Silicon Photomultipliers (SiPMs) are new photon-detectors which have been increasingly used in particle physics. Their small size, good single photon resolution, simple readout, and immunity to magnetic fields offers benefits compared to traditional photomultipliers. LYSO and CeBr3 crystals are relatively new scintillators with high stopping power, very good light yield and fast decay time. The response of these detectors to low energy gamma rays will be presented. NASA Pennsylvania Space Grant Consortium.

Refolding Active Human DNA Polymerase ν from Inclusion Bodies

PubMed Central

Arana, Mercedes E.; Powell, Gary K.; Edwards, Lori L.; Kunkel, Thomas A.; Petrovich, Robert M.

2017-01-01

Human DNA polymerase ν (Pol ν) is a conserved family A DNA polymerase of uncertain biological function. Physical and biochemical characterization aimed at understanding Pol ν function is hindered by the fact that, when over-expressed in E. coli, Pol ν is largely insoluble, and the small amount of soluble protein is difficult to purify. Here we describe the use of high hydrostatic pressure to refold Pol ν from inclusion bodies, in soluble and active form. The refolded Pol ν has properties comparable to those of the small amount of Pol ν that was purified from the soluble fraction. The approach described here may be applicable to other DNA polymerases that are expressed as insoluble inclusion bodies in E. coli. PMID:19853037

TF4SM: A Framework for Developing Traceability Solutions in Small Manufacturing Companies

PubMed Central

Bordel Sánchez, Borja; Alcarria, Ramón; Martín, Diego; Robles, Tomás

2015-01-01

Nowadays, manufacturing processes have become highly complex. Besides, more and more, governmental institutions require companies to implement systems to trace a product’s life (especially for foods, clinical materials or similar items). In this paper, we propose a new framework, based on cyber-physical systems, for developing traceability systems in small manufacturing companies (which because of their size cannot implement other commercial products). We propose a general theoretical framework, study the requirements of these companies in relation to traceability systems, propose a reference architecture based on both previous elements and build the first minimum functional prototype, to compare our solution to a traditional tag-based traceability system. Results show that our system reduces the number of inefficiencies and reaction time. PMID:26610509

Parent oriented teacher selection causes language diversity.

PubMed

Cimentepe, Ibrahim; Bingol, Haluk O

2017-09-21

An evolutionary model for emergence of diversity in language is developed. We investigated the effects of two real life observations, namely, people prefer people that they communicate with well, and people interact with people that are physically close to each other. Clearly these groups are relatively small compared to the entire population. We restrict selection of the teachers from such small groups, called imitation sets, around parents. Then the child learns language from a teacher selected within the imitation set of her parent. As a result, there are subcommunities with their own languages developed. Within subcommunity comprehension is found to be high. The number of languages is related to the relative size of imitation set by a power law. Copyright © 2017 Elsevier Ltd. All rights reserved.

TF4SM: A Framework for Developing Traceability Solutions in Small Manufacturing Companies.

PubMed

Bordel Sánchez, Borja; Alcarria, Ramón; Martín, Diego; Robles, Tomás

2015-11-20

Nowadays, manufacturing processes have become highly complex. Besides, more and more, governmental institutions require companies to implement systems to trace a product's life (especially for foods, clinical materials or similar items). In this paper, we propose a new framework, based on cyber-physical systems, for developing traceability systems in small manufacturing companies (which because of their size cannot implement other commercial products). We propose a general theoretical framework, study the requirements of these companies in relation to traceability systems, propose a reference architecture based on both previous elements and build the first minimum functional prototype, to compare our solution to a traditional tag-based traceability system. Results show that our system reduces the number of inefficiencies and reaction time.

Physical and chemical characteristics of cenospheres from the combustion of heavy fuel oil

NASA Technical Reports Server (NTRS)

Clayton, R. M.; Back, L. H.

1989-01-01

Photomicrography of particle cross sections, measurements of density, porosity, and surface area, and determinations of chemical compositions, have been used in conjunction with SEM of surface structure to characterize cenospheres generated by combustion of residual oil in a steam power plant. Large and small cenospheres, which respectively fall into the 100-200 and small 20-40 micron range, are spheroidal and hollow, with at least one blowhole; outer/inner diameter ratios for the shells are of the order of 1.3-1.4. Typically, a cenosphere contains only about 18 vol pct solid material. The presence of S, Fe, Na, and V in substantial concentrations presage high temperature heat exchanger surface corrosion problems due to cenosphere deposition.

Mitochondrial-nuclear interactions and accelerated compensatory evolution: evidence from the primate cytochrome C oxidase complex.

PubMed

Osada, Naoki; Akashi, Hiroshi

2012-01-01

Accelerated rates of mitochondrial protein evolution have been proposed to reflect Darwinian coadaptation for efficient energy production for mammalian flight and brain activity. However, several features of mammalian mtDNA (absence of recombination, small effective population size, and high mutation rate) promote genome degradation through the accumulation of weakly deleterious mutations. Here, we present evidence for "compensatory" adaptive substitutions in nuclear DNA- (nDNA) encoded mitochondrial proteins to prevent fitness decline in primate mitochondrial protein complexes. We show that high mutation rate and small effective population size, key features of primate mitochondrial genomes, can accelerate compensatory adaptive evolution in nDNA-encoded genes. We combine phylogenetic information and the 3D structure of the cytochrome c oxidase (COX) complex to test for accelerated compensatory changes among interacting sites. Physical interactions among mtDNA- and nDNA-encoded components are critical in COX evolution; amino acids in close physical proximity in the 3D structure show a strong tendency for correlated evolution among lineages. Only nuclear-encoded components of COX show evidence for positive selection and adaptive nDNA-encoded changes tend to follow mtDNA-encoded amino acid changes at nearby sites in the 3D structure. This bias in the temporal order of substitutions supports compensatory weak selection as a major factor in accelerated primate COX evolution.

Classifying Black Hole States with Machine Learning

NASA Astrophysics Data System (ADS)

Huppenkothen, Daniela

2018-01-01

Galactic black hole binaries are known to go through different states with apparent signatures in both X-ray light curves and spectra, leading to important implications for accretion physics as well as our knowledge of General Relativity. Existing frameworks of classification are usually based on human interpretation of low-dimensional representations of the data, and generally only apply to fairly small data sets. Machine learning, in contrast, allows for rapid classification of large, high-dimensional data sets. In this talk, I will report on advances made in classification of states observed in Black Hole X-ray Binaries, focusing on the two sources GRS 1915+105 and Cygnus X-1, and show both the successes and limitations of using machine learning to derive physical constraints on these systems.

Simple Emergent Power Spectra from Complex Inflationary Physics

NASA Astrophysics Data System (ADS)

Dias, Mafalda; Frazer, Jonathan; Marsh, M. C. David

2016-09-01

We construct ensembles of random scalar potentials for Nf-interacting scalar fields using nonequilibrium random matrix theory, and use these to study the generation of observables during small-field inflation. For Nf=O (few ), these heavily featured scalar potentials give rise to power spectra that are highly nonlinear, at odds with observations. For Nf≫1 , the superhorizon evolution of the perturbations is generically substantial, yet the power spectra simplify considerably and become more predictive, with most realizations being well approximated by a linear power spectrum. This provides proof of principle that complex inflationary physics can give rise to simple emergent power spectra. We explain how these results can be understood in terms of large Nf universality of random matrix theory.

Results on 3D interconnection from AIDA WP3

NASA Astrophysics Data System (ADS)

Moser, Hans-Günther; AIDA-WP3

2016-09-01

From 2010 to 2014 the EU funded AIDA project established in one of its work packages (WP3) a network of groups working collaboratively on advanced 3D integration of electronic circuits and semiconductor sensors for applications in particle physics. The main motivation came from the severe requirements on pixel detectors for tracking and vertexing at future Particle Physics experiments at LHC, super-B factories and linear colliders. To go beyond the state-of-the-art, the main issues were studying low mass, high bandwidth applications, with radiation hardness capabilities, with low power consumption, offering complex functionality, with small pixel size and without dead regions. The interfaces and interconnects of sensors to electronic readout integrated circuits are a key challenge for new detector applications.

Simple Emergent Power Spectra from Complex Inflationary Physics.

PubMed

Dias, Mafalda; Frazer, Jonathan; Marsh, M C David

2016-09-30

We construct ensembles of random scalar potentials for N_{f}-interacting scalar fields using nonequilibrium random matrix theory, and use these to study the generation of observables during small-field inflation. For N_{f}=O(few), these heavily featured scalar potentials give rise to power spectra that are highly nonlinear, at odds with observations. For N_{f}≫1, the superhorizon evolution of the perturbations is generically substantial, yet the power spectra simplify considerably and become more predictive, with most realizations being well approximated by a linear power spectrum. This provides proof of principle that complex inflationary physics can give rise to simple emergent power spectra. We explain how these results can be understood in terms of large N_{f} universality of random matrix theory.

Floquet-Engineered Valleytronics in Dirac Systems.

PubMed

Kundu, Arijit; Fertig, H A; Seradjeh, Babak

2016-01-08

Valley degrees of freedom offer a potential resource for quantum information processing if they can be effectively controlled. We discuss an optical approach to this problem in which intense light breaks electronic symmetries of a two-dimensional Dirac material. The resulting quasienergy structures may then differ for different valleys, so that the Floquet physics of the system can be exploited to produce highly polarized valley currents. This physics can be utilized to realize a valley valve whose behavior is determined optically. We propose a concrete way to achieve such valleytronics in graphene as well as in a simple model of an inversion-symmetry broken Dirac material. We study the effect numerically and demonstrate its robustness against moderate disorder and small deviations in optical parameters.

Effects of Physical Exercise on the Intestinal Mucosa of Rats Submitted to a Hypothalamic Obesity Condition.

PubMed

Gomes, J R; Freitas, J R; Grassiolli, S

2016-10-01

The small intestine plays a role in obesity as well as in satiation. However, the effect of physical exercise on the morphology and function of the small intestine during obesity has not been reported to date. This study aimed to evaluate the effects of physical exercise on morphological aspects of the rat small intestine during hypothalamic monosodium glutamate (MSG)-induced obesity. The rats were divided into four groups: Sedentary (S), Monosodium Glutamate (MSG), Exercised (E), and Exercised Monosodium Glutamate (EMSG). The MSG and EMSG groups received a daily injection of monosodium glutamate (4 g/kg) during the 5 first days after birth. The S and E groups were considered as control groups and received injections of saline. At weaning, at 21 days after birth, the EMSG and E groups were submitted to swimming practice 3 times a week until the 90th day, when all groups were sacrificed and the parameters studied recorded. Exercise significantly reduced fat deposits and the Lee Index in MSG-treated animals, and also reduced the thickness of the intestinal wall, the number of goblet cells and intestinal alkaline phosphatase activity. However, physical activity alone increased the thickness and height of villi, and the depth of the crypts. In conclusion, regular physical exercise may alter the morphology or/and functions of the small intestine, reducing the prejudicial effects of hypothalamic obesity. Anat Rec, 299:1389-1396, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

1977-78 Survey of Physics and Astronomy Bachelor's Degree Recipients. AIP Report.

ERIC Educational Resources Information Center

Ellis, Susanne D.

A 1977-78 survey of bachelor's degree recipients in physics and astronomy investigated graduates' postbaccalaureate plans. Highlights of the findings are: a small shift in postbaccalaureate plans away from graduate study and into employment for both physics and astronomy bachelors; an improved employment outlook for physics graduates with regard…

The Process of Physics Teaching Assistants' Pedagogical Content Knowledge Development

ERIC Educational Resources Information Center

Seung, Eulsun

2013-01-01

This study explored the process of physics teaching assistants' (TAs) PCK development in the context of teaching a new undergraduate introductory physics course. "Matter and Interactions" (M&I) has recently adopted a new introductory physics course that focuses on the application of a small number of fundamental physical…

13 CFR 123.202 - How much can my business borrow with a physical disaster business loan?

Code of Federal Regulations, 2010 CFR

2010-01-01

... with a physical disaster business loan? 123.202 Section 123.202 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.202 How much can my business borrow with a physical disaster business loan? (a) Disaster business loans, including both...

13 CFR 123.202 - How much can my business borrow with a physical disaster business loan?

Code of Federal Regulations, 2011 CFR

2011-01-01

... with a physical disaster business loan? 123.202 Section 123.202 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.202 How much can my business borrow with a physical disaster business loan? (a) Disaster business loans, including both...

13 CFR 123.202 - How much can my business borrow with a physical disaster business loan?

Code of Federal Regulations, 2012 CFR

2012-01-01

... with a physical disaster business loan? 123.202 Section 123.202 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.202 How much can my business borrow with a physical disaster business loan? (a) Disaster business loans, including both...

13 CFR 123.202 - How much can my business borrow with a physical disaster business loan?

Code of Federal Regulations, 2014 CFR

2014-01-01

... with a physical disaster business loan? 123.202 Section 123.202 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.202 How much can my business borrow with a physical disaster business loan? (a) Disaster business loans, including both...

13 CFR 123.202 - How much can my business borrow with a physical disaster business loan?

Code of Federal Regulations, 2013 CFR

2013-01-01

... with a physical disaster business loan? 123.202 Section 123.202 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.202 How much can my business borrow with a physical disaster business loan? (a) Disaster business loans, including both...

Small-Scale Smart Grid Construction and Analysis

NASA Astrophysics Data System (ADS)

Surface, Nicholas James

The smart grid (SG) is a commonly used catch-phrase in the energy industry yet there is no universally accepted definition. The objectives and most useful concepts have been investigated extensively in economic, environmental and engineering research by applying statistical knowledge and established theories to develop simulations without constructing physical models. In this study, a small-scale version (SSSG) is constructed to physically represent these ideas so they can be evaluated. Results of construction show data acquisition three times more expensive than the grid itself although mainly due to the incapability to downsize 70% of data acquisition costs to small-scale. Experimentation on the fully assembled grid exposes the limitations of low cost modified sine wave power, significant enough to recommend pure sine wave investment in future SSSG iterations. Findings can be projected to full-size SG at a ratio of 1:10, based on the appliance representing average US household peak daily load. However this exposes disproportionalities in the SSSG compared with previous SG investigations and recommended changes for future iterations are established to remedy this issue. Also discussed are other ideas investigated in the literature and their suitability for SSSG incorporation. It is highly recommended to develop a user-friendly bidirectional charger to more accurately represent vehicle-to-grid (V2G) infrastructure. Smart homes, BEV swap stations and pumped hydroelectric storage can also be researched on future iterations of the SSSG.

Initial Outcomes of a Participatory-Based, Competency-Building Approach to Increasing Physical Education Teachers' Physical Activity Promotion and Students' Physical Activity: A Pilot Study

ERIC Educational Resources Information Center

Weaver, R. Glenn; Webster, Collin A.; Beets, Michael W.; Brazendale, Keith; Chandler, Jessica; Schisler, Lauren; Aziz, Mazen

2018-01-01

This study examined the initial effects of a participatory-based, competency-/skill-building professional development workshop for physical education (PE) teachers on the use of physical activity (PA) promotion practices (e.g., eliminating lines, small-sided games) and students' moderate-to-vigorous physical activity (MVPA). A total of 823…

Multilayered nano-architecture of variable sized graphene nanosheets for enhanced supercapacitor electrode performance.

PubMed

Biswas, Sanjib; Drzal, Lawrence T

2010-08-01

The diverse physical and chemical aspects of graphene nanosheets such as particle size surface area and edge chemistry were combined to fabricate a new supercapacitor electrode architecture consisting of a highly aligned network of large-sized nanosheets as a series of current collectors within a multilayer configuration of bulk electrode. Capillary driven self-assembly of monolayers of graphene nanosheets was employed to create a flexible, multilayer, free-standing film of highly hydrophobic nanosheets over large macroscopic areas. This nanoarchitecture exhibits a high-frequency capacitative response and a nearly rectangular cyclic voltammogram at 1000 mV/s scanning rate and possesses a rapid current response, small equivalent series resistance (ESR), and fast ionic diffusion for high-power electrical double-layer capacitor (EDLC) application.

Explore the high-density QCD medium via particle correlations in pPb collisions at CMS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Wei, E-mail: wl33@rice.edu

2015-01-15

The observation of a long-range, near-side two-particle correlation (“ridge”) in very high multiplicity proton–proton and proton–lead collisions has opened up new opportunity of studying novel QCD phenomena in small collision systems. In 2013, high luminosity pPb data were collected by the CMS experiment at the LHC. New results of two- and multi-particle correlations in pPb collisions from CMS are presented over a wide event multiplicity and transverse momentum range. A direct comparison of pPb and PbPb systems is provided. Physics implications, especially in the context of color glass condensate and hydrodynamics models are also discussed.

2016 Final Reports from the Los Alamos National Laboratory Computational Physics Student Summer Workshop

DOE Office of Scientific and Technical Information (OSTI.GOV)

Runnels, Scott Robert; Bachrach, Harrison Ian; Carlson, Nils

The two primary purposes of LANL’s Computational Physics Student Summer Workshop are (1) To educate graduate and exceptional undergraduate students in the challenges and applications of computational physics of interest to LANL, and (2) Entice their interest toward those challenges. Computational physics is emerging as a discipline in its own right, combining expertise in mathematics, physics, and computer science. The mathematical aspects focus on numerical methods for solving equations on the computer as well as developing test problems with analytical solutions. The physics aspects are very broad, ranging from low-temperature material modeling to extremely high temperature plasma physics, radiation transportmore » and neutron transport. The computer science issues are concerned with matching numerical algorithms to emerging architectures and maintaining the quality of extremely large codes built to perform multi-physics calculations. Although graduate programs associated with computational physics are emerging, it is apparent that the pool of U.S. citizens in this multi-disciplinary field is relatively small and is typically not focused on the aspects that are of primary interest to LANL. Furthermore, more structured foundations for LANL interaction with universities in computational physics is needed; historically interactions rely heavily on individuals’ personalities and personal contacts. Thus a tertiary purpose of the Summer Workshop is to build an educational network of LANL researchers, university professors, and emerging students to advance the field and LANL’s involvement in it.« less

Small-scale dynamo at low magnetic Prandtl numbers

NASA Astrophysics Data System (ADS)

Schober, Jennifer; Schleicher, Dominik; Bovino, Stefano; Klessen, Ralf S.

2012-12-01

The present-day Universe is highly magnetized, even though the first magnetic seed fields were most probably extremely weak. To explain the growth of the magnetic field strength over many orders of magnitude, fast amplification processes need to operate. The most efficient mechanism known today is the small-scale dynamo, which converts turbulent kinetic energy into magnetic energy leading to an exponential growth of the magnetic field. The efficiency of the dynamo depends on the type of turbulence indicated by the slope of the turbulence spectrum v(ℓ)∝ℓϑ, where v(ℓ) is the eddy velocity at a scale ℓ. We explore turbulent spectra ranging from incompressible Kolmogorov turbulence with ϑ=1/3 to highly compressible Burgers turbulence with ϑ=1/2. In this work, we analyze the properties of the small-scale dynamo for low magnetic Prandtl numbers Pm, which denotes the ratio of the magnetic Reynolds number, Rm, to the hydrodynamical one, Re. We solve the Kazantsev equation, which describes the evolution of the small-scale magnetic field, using the WKB approximation. In the limit of low magnetic Prandtl numbers, the growth rate is proportional to Rm(1-ϑ)/(1+ϑ). We furthermore discuss the critical magnetic Reynolds number Rmcrit, which is required for small-scale dynamo action. The value of Rmcrit is roughly 100 for Kolmogorov turbulence and 2700 for Burgers. Furthermore, we discuss that Rmcrit provides a stronger constraint in the limit of low Pm than it does for large Pm. We conclude that the small-scale dynamo can operate in the regime of low magnetic Prandtl numbers if the magnetic Reynolds number is large enough. Thus, the magnetic field amplification on small scales can take place in a broad range of physical environments and amplify week magnetic seed fields on short time scales.

Small-scale dynamo at low magnetic Prandtl numbers.

PubMed

Schober, Jennifer; Schleicher, Dominik; Bovino, Stefano; Klessen, Ralf S

2012-12-01

The present-day Universe is highly magnetized, even though the first magnetic seed fields were most probably extremely weak. To explain the growth of the magnetic field strength over many orders of magnitude, fast amplification processes need to operate. The most efficient mechanism known today is the small-scale dynamo, which converts turbulent kinetic energy into magnetic energy leading to an exponential growth of the magnetic field. The efficiency of the dynamo depends on the type of turbulence indicated by the slope of the turbulence spectrum v(ℓ)∝ℓ^{ϑ}, where v(ℓ) is the eddy velocity at a scale ℓ. We explore turbulent spectra ranging from incompressible Kolmogorov turbulence with ϑ=1/3 to highly compressible Burgers turbulence with ϑ=1/2. In this work, we analyze the properties of the small-scale dynamo for low magnetic Prandtl numbers Pm, which denotes the ratio of the magnetic Reynolds number, Rm, to the hydrodynamical one, Re. We solve the Kazantsev equation, which describes the evolution of the small-scale magnetic field, using the WKB approximation. In the limit of low magnetic Prandtl numbers, the growth rate is proportional to Rm^{(1-ϑ)/(1+ϑ)}. We furthermore discuss the critical magnetic Reynolds number Rm_{crit}, which is required for small-scale dynamo action. The value of Rm_{crit} is roughly 100 for Kolmogorov turbulence and 2700 for Burgers. Furthermore, we discuss that Rm_{crit} provides a stronger constraint in the limit of low Pm than it does for large Pm. We conclude that the small-scale dynamo can operate in the regime of low magnetic Prandtl numbers if the magnetic Reynolds number is large enough. Thus, the magnetic field amplification on small scales can take place in a broad range of physical environments and amplify week magnetic seed fields on short time scales.

Experimental plasma research project summaries

NASA Astrophysics Data System (ADS)

1992-06-01

This is the latest in a series of Project Summary books that date back to 1976. It is the first after a hiatus of several years. They are published to provide a short description of each project supported by the Experimental Plasma Research Branch of the Division of Applied Plasma Physics in the Office of Fusion Energy. The Experimental Plasma Research Branch seeks to provide a broad range of experimental data, physics understanding, and new experimental techniques that contribute to operation, interpretation, and improvement of high temperature plasma as a source of fusion energy. In pursuit of these objectives, the branch supports research at universities, DOE laboratories, other federal laboratories, and industry. About 70 percent of the funds expended are spent at universities and a significant function of this program is the training of students in fusion physics. The branch supports small- and medium-scale experimental studies directly related to specific critical plasma issues of the magnetic fusion program. Plasma physics experiments are conducted on transport of particles and energy within plasma. Additionally, innovative approaches for operating, controlling, and heating plasma are evaluated for application to the larger confinement devices of the magnetic fusion program. New diagnostic approaches to measuring the properties of high temperature plasmas are developed to the point where they can be applied with confidence on the large-scale confinement experiments. Atomic data necessary for impurity control, interpretation of diagnostic data, development of heating devices, and analysis of cooling by impurity ion radiation are obtained. The project summaries are grouped into the three categories of plasma physics, diagnostic development, and atomic physics.

Characterizing the gender gap in introductory physics

NASA Astrophysics Data System (ADS)

Kost, Lauren E.; Pollock, Steven J.; Finkelstein, Noah D.

2009-06-01

Previous research [S. J. Pollock , Phys. Rev. ST Phys. Educ. Res. 3, 1 (2007)] showed that despite the use of interactive engagement techniques, the gap in performance between males and females on a conceptual learning survey persisted from pretest to post-test at the University of Colorado at Boulder. Such findings were counter to previously published work [M. Lorenzo , Am. J. Phys. 74, 118 (2006)]. This study begins by identifying a variety of other gender differences. There is a small but significant difference in the course grades of males and females. Males and females have significantly different prior understandings of physics and mathematics. Females are less likely to take high school physics than males, although they are equally likely to take high school calculus. Males and females also differ in their incoming attitudes and beliefs about physics. This collection of background factors is analyzed to determine the extent to which each factor correlates with performance on a conceptual post-test and with gender. Binned by quintiles, we observe that males and females with similar pretest scores do not have significantly different post-test scores (p>0.2) . The post-test data are then modeled using two regression models (multiple regression and logistic regression) to estimate the gender gap in post-test scores after controlling for these important prior factors. These prior factors account for about 70% of the observed gender gap. The results indicate that the gender gap exists in interactive physics classes at our institution but is largely associated with differences in previous physics and math knowledge and incoming attitudes and beliefs.

75 FR 61228 - Data Collection Available for Public Comments and Recommendations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-04

... SMALL BUSINESS ADMINISTRATION Data Collection Available for Public Comments and Recommendations... Data.'' Description of Respondents: Small Businesses that have experienced a physical or economic..., this notice announces the Small Business Administration's intentions to request approval on a new and...

Can a small-changes approach help address the obesity epidemic? A report of the Joint Task Force of the American Society for Nutrition, Institute of Food Technologists, and International Food Information Council.

PubMed

Hill, James O

2009-02-01

The continued rise in obesity rates in most countries suggests that current programs and initiatives designed to combat obesity have not been successful in reversing the obesity epidemic. Obesity rates are increasing because of a gradual weight gain in most populations. There has been little long-term success in treating established obesity through lifestyle change, perhaps because of the large permanent changes in diet and physical activity required to keep weight off. An alternative strategy to address the obesity epidemic involves not focusing on weight loss but promoting small changes in diet and physical activity to initially prevent further weight gain. With the use of this strategy, obesity rates could first be stabilized in most populations and then, over time, decrease gradually. Supporting data show that small reductions in conscious energy intake and increases in physical activity can reduce excessive weight gain. The opportunity exists to use the small-changes approach to bring different stakeholders together to create a national initiative to address the global epidemic of obesity. The Joint Task Force of the American Society for Nutrition, Institute of Food Technologists, and International Food Information Council believe that a small-changes framework, aimed at helping people make conscious small changes in lifestyle behaviors, in combination with efforts by the private sector to gradually "ratchet down" some of the environmental factors that have contributed to excessive energy intake and the declining rates of physical activity, can be successful in reducing obesity rates. Such an initiative would benefit from the support of educational and social marketing campaigns developed with governmental input and support.

Comprehensive definition of genome features in Spirodela polyrhiza by high-depth physical mapping and short-read DNA sequencing strategies.

PubMed

Michael, Todd P; Bryant, Douglas; Gutierrez, Ryan; Borisjuk, Nikolai; Chu, Philomena; Zhang, Hanzhong; Xia, Jing; Zhou, Junfei; Peng, Hai; El Baidouri, Moaine; Ten Hallers, Boudewijn; Hastie, Alex R; Liang, Tiffany; Acosta, Kenneth; Gilbert, Sarah; McEntee, Connor; Jackson, Scott A; Mockler, Todd C; Zhang, Weixiong; Lam, Eric

2017-02-01

Spirodela polyrhiza is a fast-growing aquatic monocot with highly reduced morphology, genome size and number of protein-coding genes. Considering these biological features of Spirodela and its basal position in the monocot lineage, understanding its genome architecture could shed light on plant adaptation and genome evolution. Like many draft genomes, however, the 158-Mb Spirodela genome sequence has not been resolved to chromosomes, and important genome characteristics have not been defined. Here we deployed rapid genome-wide physical maps combined with high-coverage short-read sequencing to resolve the 20 chromosomes of Spirodela and to empirically delineate its genome features. Our data revealed a dramatic reduction in the number of the rDNA repeat units in Spirodela to fewer than 100, which is even fewer than that reported for yeast. Consistent with its unique phylogenetic position, small RNA sequencing revealed 29 Spirodela-specific microRNA, with only two being shared with Elaeis guineensis (oil palm) and Musa balbisiana (banana). Combining DNA methylation data and small RNA sequencing enabled the accurate prediction of 20.5% long terminal repeats (LTRs) that doubled the previous estimate, and revealed a high Solo:Intact LTR ratio of 8.2. Interestingly, we found that Spirodela has the lowest global DNA methylation levels (9%) of any plant species tested. Taken together our results reveal a genome that has undergone reduction, likely through eliminating non-essential protein coding genes, rDNA and LTRs. In addition to delineating the genome features of this unique plant, the methodologies described and large-scale genome resources from this work will enable future evolutionary and functional studies of this basal monocot family. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

Influence of game format and number of players on heart rate responses and physical demands in small-sided soccer games.

PubMed

Castellano, Julen; Casamichana, David; Dellal, Alexandre

2013-05-01

The aim of the study was to examine the extent to which changing the game format (possession play vs. regulation goals and goalkeepers vs. small goals only) and the number of players (3 vs. 3, 5 vs. 5 and 7 vs. 7) influenced the physiological and physical demands of small-sided games (SSGs) in soccer in semiprofessional players. Fourteen semiprofessional male soccer players were monitored with global positioning system and heart rate devices. Heart rate, player load, distance covered, running speed, and the number of accelerations were recorded for 9 different SSGs. The results show that changes both in game format and the number of players affect the players' physiological and physical demands. Possession play places greater physiological and physical demands on players, although reducing the number of players only increases the physiological load. In the 7 vs. 7 games, changing the game format did not alter the heart rate responses. Finally, in the possession play format, changing the number of players did not produce significant differences in heart rate responses, although physical demands did decrease in line with a reduction in the number of players. These results should help coaches to understand how modifying different aspects of SSGs has a differential effect on the players' physiological and physical demands. Moreover, coaches in semiprofessional and amateur teams have now consistent information to design and optimize their training time in mixing the technical, tactical, and physical aspects.

The peculiar shapes of Saturn's small inner moons as evidence of mergers of similar-sized moonlets

NASA Astrophysics Data System (ADS)

Leleu, A.; Jutzi, M.; Rubin, M.

2018-05-01

The Cassini spacecraft revealed the spectacular, highly irregular shapes of the small inner moons of Saturn1, ranging from the unique 'ravioli-like' forms of Pan and Atlas2,3 to the highly elongated structure of Prometheus. Closest to Saturn, these bodies provide important clues regarding the formation process of small moons in close orbits around their host planet4, but their range of irregular shapes has not been explained yet. Here, we show that the spectrum of shapes among Saturn's small moons is a natural outcome of merging collisions among similar-sized moonlets possessing physical properties and orbits that are consistent with those of the current moons. A significant fraction of such merging collisions take place either at the first encounter or after 1-2 hit-and-run events, with impact velocities in the range of 1-5 times the mutual escape velocity. Close to head-on mergers result in flattened objects with large equatorial ridges, as observed on Atlas and Pan. With slightly more oblique impact angles, collisions lead to elongated, Prometheus-like shapes. These results suggest that the current forms of the small moons provide direct evidence of the processes at the final stages of their formation, involving pairwise encounters of moonlets of comparable size4-6. Finally, we show that this mechanism may also explain the formation of Iapetus' equatorial ridge7, as well as its oblate shape8.

Differences in Perceived Competence and Physical Activity Levels during Single-Gender Modified Basketball Game Play in Middle School Physical Education

ERIC Educational Resources Information Center

Slingerland, Menno; Haerens, Leen; Cardon, Greet; Borghouts, Lars

2014-01-01

Creating environments in physical education (PE) that foster perceived competence and physical activity during gender-mixed game play lessons is a challenge, especially with adolescent girls. This study is a small experiment in one PE lesson that aimed to increase the perceived competence and in-class physical activity in girls, by applying a…

Reliability and minimal detectable change of physical performance measures in individuals with pre-manifest and manifest Huntington disease.

PubMed

Quinn, Lori; Khalil, Hanan; Dawes, Helen; Fritz, Nora E; Kegelmeyer, Deb; Kloos, Anne D; Gillard, Jonathan W; Busse, Monica

2013-07-01

Clinical intervention trials in people with Huntington disease (HD) have been limited by a lack of reliable and appropriate outcome measures. The purpose of this study was to determine the reliability and minimal detectable change (MDC) of various outcome measures that are potentially suitable for evaluating physical functioning in individuals with HD. This was a multicenter, prospective, observational study. Participants with pre-manifest and manifest HD (early, middle, and late stages) were recruited from 8 international sites to complete a battery of physical performance and functional measures at 2 assessments, separated by 1 week. Test-retest reliability (using intraclass correlation coefficients) and MDC values were calculated for all measures. Seventy-five individuals with HD (mean age=52.12 years, SD=11.82) participated in the study. Test-retest reliability was very high (>.90) for participants with manifest HD for the Six-Minute Walk Test (6MWT), 10-Meter Walk Test, Timed "Up & Go" Test (TUG), Berg Balance Scale (BBS), Physical Performance Test (PPT), Barthel Index, Rivermead Mobility Index, and Tinetti Mobility Test (TMT). Many MDC values suggested a relatively high degree of inherent variability, particularly in the middle stage of HD. Minimum detectable change values for participants with manifest HD that were relatively low across disease stages were found for the BBS (5), PPT (5), and TUG (2.98). For individuals with pre-manifest HD (n=11), the 6MWT and Four Square Step Test had high reliability and low MDC values. The sample size for the pre-manifest HD group was small. The BBS, PPT, and TUG appear most appropriate for clinical trials aimed at improving physical functioning in people with manifest HD. Further research in people with pre-manifest HD is necessary.

The Physics Learning Program at the University of Wisconsin-Madison

NASA Astrophysics Data System (ADS)

Nossal, S. M.; Watson, L.; Huesmann, A.; Jacob, A.; Fretz, J.; Clarke, M.

2006-05-01

The Physics Learning Program at the University of Wisconsin-Madison provides a supportive learning environment for students studying physics. We pair staff and upper level physics and secondary science education majors in small study groups with students studying introductory physics. Approximately 33-50% of our students are from racial and ethnic groups underrepresented in the sciences. In addition, students participating in our program include others who may be feeling isolated such as first-generation college students, returning adults, students with disabilities, international students, and students from small rural schools; as well as students with weak math and physics preparation and/or who are struggling with the course. The Physics Learning Program is run in conjunction with similar programs for chemistry and biochemistry. During the past year with a move to a new building we obtained a dedicated space for the Physics Learning Program, facilitating students to form their own study groups. We also began a pilot program for students in the calculus-based physics sequence. We will discuss these additions, as well as recruitment, pedagogy, teacher training, and mentoring practices that we use with the aim of creating an inclusive learning environment.

Vorticity, backscatter and counter-gradient transport predictions using two-level simulation of turbulent flows

NASA Astrophysics Data System (ADS)

Ranjan, R.; Menon, S.

2018-04-01

The two-level simulation (TLS) method evolves both the large-and the small-scale fields in a two-scale approach and has shown good predictive capabilities in both isotropic and wall-bounded high Reynolds number (Re) turbulent flows in the past. Sensitivity and ability of this modelling approach to predict fundamental features (such as backscatter, counter-gradient turbulent transport, small-scale vorticity, etc.) seen in high Re turbulent flows is assessed here by using two direct numerical simulation (DNS) datasets corresponding to a forced isotropic turbulence at Taylor's microscale-based Reynolds number Reλ ≈ 433 and a fully developed turbulent flow in a periodic channel at friction Reynolds number Reτ ≈ 1000. It is shown that TLS captures the dynamics of local co-/counter-gradient transport and backscatter at the requisite scales of interest. These observations are further confirmed through a posteriori investigation of the flow in a periodic channel at Reτ = 2000. The results reveal that the TLS method can capture both the large- and the small-scale flow physics in a consistent manner, and at a reduced overall cost when compared to the estimated DNS or wall-resolved LES cost.

Transonic flow of steam with non-equilibrium and homogenous condensation

NASA Astrophysics Data System (ADS)

Virk, Akashdeep Singh; Rusak, Zvi

2017-11-01

A small-disturbance model for studying the physical behavior of a steady transonic flow of steam with non-equilibrium and homogeneous condensation around a thin airfoil is derived. The steam thermodynamic behavior is described by van der Waals equation of state. The water condensation rate is calculated according to classical nucleation and droplet growth models. The current study is based on an asymptotic analysis of the fluid flow and condensation equations and boundary conditions in terms of the small thickness of the airfoil, small angle of attack, closeness of upstream flow Mach number to unity and small amount of condensate. The asymptotic analysis gives the similarity parameters that govern the problem. The flow field may be described by a non-homogeneous transonic small-disturbance equation coupled with a set of four ordinary differential equations for the calculation of the condensate mass fraction. An iterative numerical scheme which combines Murman & Cole's (1971) method with Simpson's integration rule is applied to solve the coupled system of equations. The model is used to study the effects of energy release from condensation on the aerodynamic performance of airfoils operating at high pressures and temperatures and near the vapor-liquid saturation conditions.

ForwArd Search ExpeRiment at the LHC

NASA Astrophysics Data System (ADS)

Feng, Jonathan L.; Galon, Iftah; Kling, Felix; Trojanowski, Sebastian

2018-02-01

New physics has traditionally been expected in the high-pT region at high-energy collider experiments. If new particles are light and weakly coupled, however, this focus may be completely misguided: light particles are typically highly concentrated within a few mrad of the beam line, allowing sensitive searches with small detectors, and even extremely weakly coupled particles may be produced in large numbers there. We propose a new experiment, forward search experiment, or FASER, which would be placed downstream of the ATLAS or CMS interaction point (IP) in the very forward region and operated concurrently there. Two representative on-axis locations are studied: a far location, 400 m from the IP and just off the beam tunnel, and a near location, just 150 m from the IP and right behind the TAN neutral particle absorber. For each location, we examine leading neutrino- and beam-induced backgrounds. As a concrete example of light, weakly coupled particles, we consider dark photons produced through light meson decay and proton bremsstrahlung. We find that even a relatively small and inexpensive cylindrical detector, with a radius of ˜10 cm and length of 5-10 m, depending on the location, can discover dark photons in a large and unprobed region of parameter space with dark photon mass mA'˜10 - 500 MeV and kinetic mixing parameter ɛ ˜10-6-10-3. FASER will clearly also be sensitive to many other forms of new physics. We conclude with a discussion of topics for further study that will be essential for understanding FASER's feasibility, optimizing its design, and realizing its discovery potential.

Shape Analysis and Deployment of the ExaVolt Antenna

NASA Astrophysics Data System (ADS)

Baginski, Frank; Zhao, Kaiyu; Furer, Joshua; Landay, Justin; Bailoor, Shantanu; Gorham, Peter; Varner, Gary; Miki, Christian; Hill, Brian; Schoorlemmer, Harm; Nguyen, Liem; Romero-Wolf, Andrew; Liewer, Kurt; Sauder, Jonathan; Brakke, Kenneth; Beatty, Jim; Connolly, Amy; Allison, Patrick; Pfendner, Carl; Dailey, Brian; Fairbrother, Debra; Said, Magdi; Lang, Steven; Young, Leyland

The ExaVolt Antenna (EVA) is the next generation balloon-borne ultra-high energy (UHE) particle observatory under development for NASA’s suborbital super-pressure balloon program in Antarctica. Unlike a typical mission where the balloon lifts a gondola that carries the primary scientific instrument, the EVA mission is a first-of-its-kind in that the balloon itself is part of the science instrument. Specifically, a toroidal RF reflector is mounted onto the outside surface of a superpressure balloon (SPB) and a feed antenna is suspended inside the balloon, creating a high-gain antenna system with a synoptic view of the Antarctic ice sheet. The EVA mission presents a number of technical challenges. For example, can a stowed feed antenna be inserted through an opening in the top-plate? Can the feed antenna be deployed during the ascent? Once float altitude is achieved, how might small shape changes in the balloon shape affect the antenna performance over the life of the EVA mission? The EVA team utilized a combination of testing with a 1/20-scale physical model, mathematical modeling and numerical simulations to probe these and related questions. While the problems are challenging, they are solvable with current technology and expertise. Experiments with a 1/20-scale EVA physical model outline a pathway for inserting a stowed feed into a SPB. Analysis indicates the EVA system will ascend, deploy and assume a stable configuration at float altitude. Nominal shape changes in an Antarctic SPB are sufficiently small to allow the use of the surface of the balloon as a high-gain reflector.

Review of technologies for oil and gas produced water treatment.

PubMed

Fakhru'l-Razi, Ahmadun; Pendashteh, Alireza; Abdullah, Luqman Chuah; Biak, Dayang Radiah Awang; Madaeni, Sayed Siavash; Abidin, Zurina Zainal

2009-10-30

Produced water is the largest waste stream generated in oil and gas industries. It is a mixture of different organic and inorganic compounds. Due to the increasing volume of waste all over the world in the current decade, the outcome and effect of discharging produced water on the environment has lately become a significant issue of environmental concern. Produced water is conventionally treated through different physical, chemical, and biological methods. In offshore platforms because of space constraints, compact physical and chemical systems are used. However, current technologies cannot remove small-suspended oil particles and dissolved elements. Besides, many chemical treatments, whose initial and/or running cost are high and produce hazardous sludge. In onshore facilities, biological pretreatment of oily wastewater can be a cost-effective and environmental friendly method. As high salt concentration and variations of influent characteristics have direct influence on the turbidity of the effluent, it is appropriate to incorporate a physical treatment, e.g., membrane to refine the final effluent. For these reasons, major research efforts in the future could focus on the optimization of current technologies and use of combined physico-chemical and/or biological treatment of produced water in order to comply with reuse and discharge limits.

Understanding the physical properties of hybrid perovskites for photovoltaic applications

NASA Astrophysics Data System (ADS)

Huang, Jinsong; Yuan, Yongbo; Shao, Yuchuan; Yan, Yanfa

2017-07-01

New photovoltaic materials have been searched for in the past decades for clean and renewable solar energy conversion with an objective of reducing the levelized cost of electricity (that is, the unit price of electricity over the course of the device lifetime). An emerging family of semiconductor materials — organic-inorganic halide perovskites (OIHPs) — are the focus of the photovoltaic research community owing to their use of low cost, nature-abundant raw materials, low-temperature and scalable solution fabrication processes, and, in particular, the very high power conversion efficiencies that have been achieved within the short time of their development. In this Review, we summarize and critically assess the most recent advances in understanding the physical properties of both 3D and low-dimensional OIHPs that favour a small open-circuit voltage deficit and high power conversion efficiency. Several prominent topics in this field on the unique properties of OIHPs are surveyed, including defect physics, ferroelectricity, exciton dissociation processes, carrier recombination lifetime and photon recycling. The impact of ion migration on solar cell efficiency and stability are also critically analysed. Finally, we discuss the remaining challenges in the commercialization of OIHP photovoltaics.

Kentucky DOE EPSCoR Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grulke, Eric; Stencel, John

2011-09-13

The KY DOE EPSCoR Program supports two research clusters. The Materials Cluster uses unique equipment and computational methods that involve research expertise at the University of Kentucky and University of Louisville. This team determines the physical, chemical and mechanical properties of nanostructured materials and examines the dominant mechanisms involved in the formation of new self-assembled nanostructures. State-of-the-art parallel computational methods and algorithms are used to overcome current limitations of processing that otherwise are restricted to small system sizes and short times. The team also focuses on developing and applying advanced microtechnology fabrication techniques and the application of microelectrornechanical systems (MEMS)more » for creating new materials, novel microdevices, and integrated microsensors. The second research cluster concentrates on High Energy and Nuclear Physics. lt connects research and educational activities at the University of Kentucky, Eastern Kentucky University and national DOE research laboratories. Its vision is to establish world-class research status dedicated to experimental and theoretical investigations in strong interaction physics. The research provides a forum, facilities, and support for scientists to interact and collaborate in subatomic physics research. The program enables increased student involvement in fundamental physics research through the establishment of graduate fellowships and collaborative work.« less

13 CFR 123.200 - Am I eligible to apply for a physical disaster business loan?

Code of Federal Regulations, 2014 CFR

2014-01-01

... physical disaster business loan? 123.200 Section 123.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.200 Am I eligible to apply for a physical disaster business loan? (a) Almost any business concern or charitable or other non-profit entity...

13 CFR 123.200 - Am I eligible to apply for a physical disaster business loan?

Code of Federal Regulations, 2012 CFR

2012-01-01

... physical disaster business loan? 123.200 Section 123.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.200 Am I eligible to apply for a physical disaster business loan? (a) Almost any business concern or charitable or other non-profit entity...

13 CFR 123.200 - Am I eligible to apply for a physical disaster business loan?

Code of Federal Regulations, 2013 CFR

2013-01-01

... physical disaster business loan? 123.200 Section 123.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.200 Am I eligible to apply for a physical disaster business loan? (a) Almost any business concern or charitable or other non-profit entity...

13 CFR 123.200 - Am I eligible to apply for a physical disaster business loan?

Code of Federal Regulations, 2011 CFR

2011-01-01

... physical disaster business loan? 123.200 Section 123.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.200 Am I eligible to apply for a physical disaster business loan? (a) Almost any business concern or charitable or other non-profit entity...

Assessing Learning in Small Sized Physics Courses

ERIC Educational Resources Information Center

Ene, Emanuela; Ackerson, Bruce J.

2018-01-01

We describe the construction, validation, and testing of a concept inventory for an "Introduction to Physics of Semiconductors" course offered by the department of physics to undergraduate engineering students. By design, this inventory addresses both content knowledge and the ability to interpret content via different cognitive…

Pediatric Small Bowel Crohn Disease: Correlation of US and MR Enterography

PubMed Central

Smith, Ethan A.; Sanchez, Ramon J.; DiPietro, Michael A.; DeMatos-Maillard, Vera; Strouse, Peter J.; Darge, Kassa

2015-01-01

Small bowel Crohn disease is commonly diagnosed during the pediatric period, and recent investigations show that its incidence is increasing in this age group. Diagnosis and follow-up of this condition are commonly based on a combination of patient history and physical examination, disease activity surveys, laboratory assessment, and endoscopy with biopsy, but imaging also plays a central role. Ultrasonography (US) is an underutilized well-tolerated imaging modality for screening and follow-up of small bowel Crohn disease in children and adolescents. US has numerous advantages over computed tomographic (CT) enterography and magnetic resonance (MR) enterography, including low cost and no required use of oral or intravenous contrast material. US also has the potential to provide images with higher spatial resolution than those obtained at CT enterography and MR enterography, allows faster examination than does MR enterography, does not involve ionizing radiation, and does not require sedation or general anesthesia. US accurately depicts small bowel and mesenteric changes related to pediatric Crohn disease, and US findings show a high correlation with MR imaging findings in this patient population. ©RSNA, 2015 PMID:25839736

Verification of Small Hole Theory for Application to Wire Chaffing Resulting in Shield Faults

NASA Technical Reports Server (NTRS)

Schuet, Stefan R.; Timucin, Dogan A.; Wheeler, Kevin R.

2011-01-01

Our work is focused upon developing methods for wire chafe fault detection through the use of reflectometry to assess shield integrity. When shielded electrical aircraft wiring first begins to chafe typically the resulting evidence is small hole(s) in the shielding. We are focused upon developing algorithms and the signal processing necessary to first detect these small holes prior to incurring damage to the inner conductors. Our approach has been to develop a first principles physics model combined with probabilistic inference, and to verify this model with laboratory experiments as well as through simulation. Previously we have presented the electromagnetic small-hole theory and how it might be applied to coaxial cable. In this presentation, we present our efforts to verify this theoretical approach with high-fidelity electromagnetic simulations (COMSOL). Laboratory observations are used to parameterize the computationally efficient theoretical model with probabilistic inference resulting in quantification of hole size and location. Our efforts in characterizing faults in coaxial cable are subsequently leading to fault detection in shielded twisted pair as well as analysis of intermittent faulty connectors using similar techniques.

Stereo Correspondence Using Moment Invariants

NASA Astrophysics Data System (ADS)

Premaratne, Prashan; Safaei, Farzad

Autonomous navigation is seen as a vital tool in harnessing the enormous potential of Unmanned Aerial Vehicles (UAV) and small robotic vehicles for both military and civilian use. Even though, laser based scanning solutions for Simultaneous Location And Mapping (SLAM) is considered as the most reliable for depth estimation, they are not feasible for use in UAV and land-based small vehicles due to their physical size and weight. Stereovision is considered as the best approach for any autonomous navigation solution as stereo rigs are considered to be lightweight and inexpensive. However, stereoscopy which estimates the depth information through pairs of stereo images can still be computationally expensive and unreliable. This is mainly due to some of the algorithms used in successful stereovision solutions require high computational requirements that cannot be met by small robotic vehicles. In our research, we implement a feature-based stereovision solution using moment invariants as a metric to find corresponding regions in image pairs that will reduce the computational complexity and improve the accuracy of the disparity measures that will be significant for the use in UAVs and in small robotic vehicles.

Solar concentrator modules with silicone-onglass Fresnel lens panels and multijunction cells.

PubMed

Rumyantsev, Valery D

2010-04-26

High-efficiency multijunction (MJ) solar cells, being very expensive to manufacture, should only be used in combination with solar concentrators in terrestrial applications. An essential cost reduction of electric power produced by photovoltaic (PV) installations with MJ cells, may be expected by the creation of highly-effective, but inexpensive, elements for optical concentration and sun tracking. This article is an overview of the corresponding approach under development at the Ioffe Physical Technical Institute. The approach to R&D of the solar PV modules is based on the concepts of sunlight concentration by small-aperture area Fresnel lenses and "all-glass" module design. The small-aperture area lenses are arranged as a panel with silicone-on-glass structure where the glass plate serves as the front surface of a module. In turn, high-efficiency InGaP/(In)GaAs/Ge cells are arranged on a rear module panel mounted on a glass plate which functions as a heat sink and integrated protective cover for the cells. The developed PV modules and sun trackers are characterized by simple design, and are regarded as the prototypes for further commercialization.

Steroid Profiling by Gas Chromatography–Mass Spectrometry and High Performance Liquid Chromatography–Mass Spectrometry for Adrenal Diseases

PubMed Central

McDonald, Jeffrey G.; Matthew, Susan

2012-01-01

The ability to measure steroid hormone concentrations in blood and urine specimens is central to the diagnosis and proper treatment of adrenal diseases. The traditional approach has been to assay each steroid hormone, precursor, or metabolite using individual aliquots of serum, each with a separate immunoassay. For complex diseases, such as congenital adrenal hyperplasia and adrenocortical cancer, in which the assay of several steroids is essential for management, this approach is time consuming and costly, in addition to using large amounts of serum. Gas chromatography/mass spectrometry profiling of steroid metabolites in urine has been employed for many years but only in a small number of specialized laboratories and suffers from slow throughput. The advent of commercial high-performance liquid chromatography instruments coupled to tandem mass spectrometers offers the potential for medium- to high-throughput profiling of serum steroids using small quantities of sample. Here, we review the physical principles of mass spectrometry, the instrumentation used for these techniques, the terminology used in this field and applications to steroid analysis. PMID:22170384

A physics-motivated Centroidal Voronoi Particle domain decomposition method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fu, Lin, E-mail: lin.fu@tum.de; Hu, Xiangyu Y., E-mail: xiangyu.hu@tum.de; Adams, Nikolaus A., E-mail: nikolaus.adams@tum.de

2017-04-15

In this paper, we propose a novel domain decomposition method for large-scale simulations in continuum mechanics by merging the concepts of Centroidal Voronoi Tessellation (CVT) and Voronoi Particle dynamics (VP). The CVT is introduced to achieve a high-level compactness of the partitioning subdomains by the Lloyd algorithm which monotonically decreases the CVT energy. The number of computational elements between neighboring partitioning subdomains, which scales the communication effort for parallel simulations, is optimized implicitly as the generated partitioning subdomains are convex and simply connected with small aspect-ratios. Moreover, Voronoi Particle dynamics employing physical analogy with a tailored equation of state ismore » developed, which relaxes the particle system towards the target partition with good load balance. Since the equilibrium is computed by an iterative approach, the partitioning subdomains exhibit locality and the incremental property. Numerical experiments reveal that the proposed Centroidal Voronoi Particle (CVP) based algorithm produces high-quality partitioning with high efficiency, independently of computational-element types. Thus it can be used for a wide range of applications in computational science and engineering.« less

A physics-motivated Centroidal Voronoi Particle domain decomposition method

NASA Astrophysics Data System (ADS)

Fu, Lin; Hu, Xiangyu Y.; Adams, Nikolaus A.

2017-04-01

In this paper, we propose a novel domain decomposition method for large-scale simulations in continuum mechanics by merging the concepts of Centroidal Voronoi Tessellation (CVT) and Voronoi Particle dynamics (VP). The CVT is introduced to achieve a high-level compactness of the partitioning subdomains by the Lloyd algorithm which monotonically decreases the CVT energy. The number of computational elements between neighboring partitioning subdomains, which scales the communication effort for parallel simulations, is optimized implicitly as the generated partitioning subdomains are convex and simply connected with small aspect-ratios. Moreover, Voronoi Particle dynamics employing physical analogy with a tailored equation of state is developed, which relaxes the particle system towards the target partition with good load balance. Since the equilibrium is computed by an iterative approach, the partitioning subdomains exhibit locality and the incremental property. Numerical experiments reveal that the proposed Centroidal Voronoi Particle (CVP) based algorithm produces high-quality partitioning with high efficiency, independently of computational-element types. Thus it can be used for a wide range of applications in computational science and engineering.

Physical activity and lung cancer among non-smokers: A pilot molecular epidemiologic study within EPIC

PubMed Central

RUNDLE, ANDREW; RICHIE, JOHN; STEINDORF, KAREN; PELUSO, MARCO; OVERVAD, KIM; RAASCHOU-NIELSEN, OLE; CLAVEL-CHAPELON, FRANCOISE; LINSEISEN, JACOB P.; BOEING, HEINER; TRICHOPOULOU, ANTONIA; PALLI, DOMENICO; KROGH, VITTORIO; TUMINO, ROSARIO; PANICO, SALVATORE; BUENO-DE-MESQUITA, HENDRIK B.; PEETERS, PETRA H.; LUND, EILIV; GONZALEZ, CARLOS A.; MARTINEZ, CARMEN; DORRONSORO, MIREN; BARRICARTE, AURELIO; TORMO, M. JOSE; QUIROS, JOSÈ R.; AGUDO, ANTONIO; BERGLUND, GORAN; JARVHOLM, BENGT; BINGHAM, SHEILA; KEY, TIMOTHY J.; GORMALLY, EMMANUELLE; SARACCI, RODOLFO; KAAKS, RUDOLF; RIBOLI, ELIO; VINEIS, PAOLO

2013-01-01

The association between physical activity, potential intermediate biomarkers and lung cancer risk was investigated in a study of 230 cases and 648 controls nested within the European Prospective Investigation of Cancer and Nutrition. Data on white blood cell aromatic-DNA adducts by 32P-postlabeling and glutathione (GSH) in red blood cells were available from a subset of cases and controls. Compared to the first quartile, the fourth quartile of recreational physical activity was associated with lower lung cancer risk [odds ratio=0.56 (0.35–0.90)], higher GSH levels [+1.87 micro mole GSH/gram haemoglobin, p=0.04] but not with the presence of high levels of adducts [odds ratio=1.05 (0.38–2.86)]. Despite being associated with recreational physical activity, in these small scale pilot analyses GSH levels were not associated with lung cancer risk, [odds ratio=0.95 (0.84 – 1.07) per unit increase in glutathione levels]. Household and occupational activity was not associated with lung cancer risk or biomarker levels. PMID:20050820

Exercise therapy in polycystic ovary syndrome.

PubMed

Hoeger, Kathleen M

2008-01-01

Women with polycystic ovary syndrome (PCOS) demonstrate a high prevalence of obesity across all populations studied. The role of decreased energy expenditure through reduced physical activity in contributing to obesity in PCOS is not well studied. The independent benefits of exercise in improving metabolic disease, cardiovascular health, and diabetes have been shown in the general population. Moderate activity incorporated into daily activities appears to be as effective in the reduction in diabetes risk and cardiovascular disease as that achieved with vigorous activity and may be more sustainable over the long-term. The role of physical activity in the management of the reproductive dysfunction of PCOS is less established, although lifestyle change incorporating increased physical activity with reduced caloric intake has shown benefit in small published trials. Studies of weight loss demonstrate an essential role for increased physical activity in maintenance of weight loss over the long-term although minimal effect in the achievement of weight loss with exercise alone. Further studies of the role for exercise in the management of reproductive dysfunction in PCOS as well as clarification of the type, frequency, and duration of exercise to achieve the best outcomes are needed.

[MicroRNAs: circulating biomarkers in type 2 Diabetes Mellitus and physical exercise].

PubMed

Gómez-Banoy, Nicolás; Mockus, Ismena

2016-03-01

MicroRNAs are small, non-coding molecules with a crucial function in the cell´s biologic regulation. Circulating levels of miRNAs may be useful biomarkers in metabolic diseases such as type 2 Diabetes Mellitus (DM2), which alters the circulating concentrations of several types of miRNA. Specific serum profiles of these molecules have been identified in high-risk patients before the development of DM2 and its chronic complications. Most importantly, these profiles can be modified with physical exercise, which is crucial in the treatment of metabolic diseases. Acute physical activity alone can induce changes in tissue specific miRNAs, and responses are different in aerobic or non-aerobic training. Muscle and cardiovascular miRNAs, which may play an important role in the adap tation to exercise, are predominantly altered. Even further, there is a correlation between serum levels of miRNAs and fitness, suggesting a role for chronic exercise in their regulation. Thus, miRNAs are molecules of growing importance in exercise physiology, and may be involved in the mechanisms behind the beneficial effects of physical activity for patients with metabolic diseases.

Unifying physical concepts of reality

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gilbert, T.L.

1983-08-01

Physics may be characterized as the science of matter and energy. It anchors the two ends of the frontiers of science: the frontier of the very small and the frontier of the very large. All of the phenomena that we observe and study at the frontiers of science - all external experiences - are manifestations of matter and energy. One may, therefore, use physics to exemplify both the diversity and unity of science. This theme will be developed in two separate examples: first by sketching, very briefly, the historical origins of frontiers of the very small and very large andmore » the converging unity of these two frontiers; and then by describing certain unifying concepts that play a central role in physics and provide a framework for relating developments in different sciences.« less

The study of the physics of cometary nuclei

NASA Technical Reports Server (NTRS)

Whipple, F. L.

1983-01-01

On the basis of the icy conglometate model of cometary nuclei various observations demonstrate the spotted nature of many or most nuclei, i.e., regions of unusual activity, either high or low. Rotation periods, spin axes and even precession of the axes have been determined. Narrow dust jets near the nuclei of some bright comets require that small sources be embedded in larger active areas. Certain evidence suggests that very dusty areas and very dusty comets may be less active, respectively, than surrounding areas or other comets.

Mach-Zehnder Interferometer Refractive Index Sensor Based on a Plasmonic Channel Waveguide

PubMed Central

Lee, Da Eun; Lee, Young Jin; Shin, Eunso; Kwon, Soon-Hong

2017-01-01

A Mach-Zehnder interferometer based on a plasmonic channel waveguide is proposed for refractive index sensing. The structure, with a small physical footprint of 20 × 120 μm2, achieved a high figure of merit of 294. The cut-off frequency behaviour in the plasmonic channel waveguide resulted in a flat dispersion curve, which induces a 1.8 times larger change of the propagation constant for the given refractive index change compared with previously reported results. PMID:29120381

Study the performance of LYSO and CeBr3 crystals using Silicon Photomultipliers

NASA Astrophysics Data System (ADS)

Kryemadhi, Abaz

2016-03-01

The Silicon Photomultipliers (SiPMs) are novel photon-detectors which have been progressively found their use in particle physics. Their small size, good single photon resolution, simple readout, and immunity to magnetic fields offers advantages compared to traditional photomultipliers. LYSO and CeBr3 crystals are relatively new scintillators with high light yield and fast decay time. The response of these detectors to low energy gamma rays and cosmic ray muons will be presented. Messiah College Workload Reallocation Program.

Fuel Properties Effect on the Performance of a Small High Temperature Rise Combustor

DTIC Science & Technology

1989-01-01

Center Cleveland, Ohio and DTIC S h cELECTStephen A. Beckel DEC 3 11990Pat Whn iraf Pratt & Whitney Aircraft West Palm Beach, Florida Ea: D S Prepared...Beckel Government Products Division Pratt & Whitney Aircraft Nest Palm Beach, Florida Abstract Fuel physical properties that govern atomiz- ation and...fuels used were JP-5, a blend of Diesel Fuel actual combustion process, there is only a slight Marine/Home Hea.ing Oil (DFM/HHO), and a blend of

The slow X-ray pulsar SXP 1062 and associated supernova remnant in the Wing of the Small Magellanic Cloud

NASA Astrophysics Data System (ADS)

Oskinova, L. M.; Guerrero, M. A.; Hénault-Brunet, V.; Sun, W.; Chu, Y.-H.; Evans, C.; Gallagher, J. S.; Gruendl, R. A.; Reyes-Iturbide, J.

2013-03-01

SXP 1062 is an exceptional case of a young neutron star in a wind-fed high-mass X-ray binary associated with a supernova remnant. A unique combination of measured spin period, its derivative, luminosity and young age makes this source a key probe for the physics of accretion and neutron star evolution. Theoretical models proposed to explain the properties of SXP 1062 shall be tested with new data.

Design and Integration of a Three Degrees-of-Freedom Robotic Vehicle with Control Moment Gyro for the Autonomous Multi-Agent Physically Interacting Spacecraft (AMPHIS) Testbed

DTIC Science & Technology

2006-09-01

required directional control for each thruster due to their high precision and equivalent power and computer interface requirements to those for the...Universal Serial Bus) ports, LPT (Line Printing Terminal) and KVM (Keyboard-Video- Mouse) interfaces. Additionally, power is supplied to the computer through...of the IDE cable to the Prometheus Development Kit ACC-IDEEXT. Connect a small drive power connector from the desktop ATX power supply to the ACC

Kinetic Methods for Predicting Flow Physics of Small Thruster Expansions

DTIC Science & Technology

2011-01-24

Zeifman, M., and Levin, D.,“Sensitivity of Water Condensation in a Super- sonic Plume to the Nucleation Rate,” Journal of Thermophysics and Heat Transfer ...M. I., and Levin, D. A., “Kinetic Model of Condensation in a Free Argon Expanding Jet,” Journal of Thermophysics and Heat Transfer , Vol. 20, No. 1...of Thermophysics and Heat Transfer , 25-28 June 2007. [44] Kumar, R. and Levin, D., “Simulation of Homogeneous Condensation of Ethanol in High

High Voltage Design Guide. Volume V. Spacecraft

DTIC Science & Technology

1983-01-01

written at Boeing). 57. Langmuir , I., and Blodgett , K. B., "Currents Limited by Space Charge Between Concentric Spheres", Physical Review 23, p. 49...Transformers 66 6.3.3 Pulse Circuits 68 6.4 Packaging 68 6.4.1 Liquids 69 6.4.2 Gases 69 6.4.3 Shielding 69 6.5 Insulation 70 6.5.1 Open Construction 71 6.5.2...percent reactive liquid insulating material used to fill all intersfices within electrical parts and assemblies such as the spaces between very small

Physics teaching in developing countries

NASA Astrophysics Data System (ADS)

Talisayon, V. M.

1984-05-01

The need for endogeneous learning materials that will relate physics to the student's culture and environment spurred countries like India, Thailand, The Philippines and Indonesia to develop their own physics curriculum materials and laboratory equipment. Meagre resources and widespread poverty necessitated the development of laboratory materials from everyday items, recycled materials and other low-cost or no-cost local materials. The process of developing learning materials for one's teaching-learning needs in physics and the search from within for solutions to one's problems contribute in no small measure to the development of self-reliance in physics teaching of a developing country. Major concerns of developing countries are food supply, livelihood, health, nutrition and growth of economy. At the level of the student and his family, food, health, and livelihood are also primary concerns. Many physics teaching problems can be overcome on a large scale, given political support and national will. In countries where national leadership recognises that science and technology developed is essential to national development and that science education in turn is crucial to science and technology development, scarce resources can be allocated to science education. In developing countries where science education receives little or no political support, the most important resource in the physics classroom is the physics teacher. A highly motivated and adequately trained teacher can rise above the constraining circumstances of paucity of material resources and government apathy. In developing countries the need is great for self-reliance in physics teaching at the country level, and more importantly at the teacher level.

Small Scale Chemical Segregation Within Keplerian Disk Candidate G35.20-0.74N

NASA Astrophysics Data System (ADS)

Allen, Veronica; van der Tak, Floris; Sánchez-Monge, Álvaro; Cesaroni, Riccardo; Beltrán, Maria T.

2016-06-01

In the study of high-mass star formation, hot cores are empirically defined stages where chemically rich emission is detected toward a massive protostar. It is unknown whether the physical origin of this emission is a disk, inner envelope, or outflow cavity wall and whether the hot core stage is common to all massive stars. With the advent of the highly sensitive sub-millimeter interferometer, ALMA, the ability to chemically characterize high mass star forming regions other than Orion has become possible. In the up-and-coming field of observational astrochemistry, these sensitive high resolution observations have opened up opportunities to find small scale variations in young protostellar sources.We have done an in depth analysis of high spatial resolution (~1000 AU) Cycle 0 ALMA observations of the high mass star forming region G35.20-0.74N, where Sánchez-Monge et al (2013) found evidence for Keplerian rotation. After further chemical analysis, numerous complex organic species have been identified in this region and we notice an interesting asymmetry in the distribution of the Nitrogen-bearing species within this source. In my talk, I will briefly outline the case for the disk and the consequences for this hypothesis following the chemical segregation we have seen.

Facilities Renewal at the Small College.

ERIC Educational Resources Information Center

Association of Physical Plant Administrators, Alexandria, VA. Association of Higher Education Facilities Officers.

This monograph on facilities renewal at small colleges offers six case studies illustrating how these small private colleges and universities managed and funded deferred maintenance. The case studies were all written by facilities directors from institutions that developed innovative strategic plans to revitalize their physical plants. The first…

Process Evaluation Results from the Healthy Directions-Small Business Study

ERIC Educational Resources Information Center

Hunt, Mary K.; Barbeau, Elizabeth M.; Lederman, Ruth; Stoddard, Anne M.; Chetkovich, Carol; Goldman, Roberta; Wallace, Lorraine; Sorensen, Glorian

2007-01-01

The Healthy Directions-Small Business randomized, controlled study aimed to reduce cancer risk among multiethnic workers in small manufacturing businesses by increasing fruit and vegetable consumption, physical activity, and daily multivitamin in take and decreasing consumption of red meat. The intervention incorporated participatory strategies…

Gender-specific associations between involvement in team sport culture and canadian adolescents' substance-use behavior.

PubMed

Boyes, Randy; O'Sullivan, Dylan E; Linden, Brooke; McIsaac, Michael; Pickett, William

2017-12-01

Canadian adolescents have some of the highest rates of substance use in the world. The etiology of this phenomenon has not been fully explored, and one possible contextual determinant is involvement in sport activities that foster risk-taking behaviors through physical and social mechanisms. Using the 2013-14 Health Behaviour in School Aged Children (HBSC) study we therefore examined this hypothesis in a contemporary national sample of Canadian adolescents. The strength and direction of the relationship between sport and substance use varied by gender and substance, with team sport participation associated with increased binge drinking (RR 1.33 [95% CI 1.13-1.56] for boys, RR 1.21 [1.06-1.38] for girls) and use of smokeless tobacco (RR 1.68 [1.34-2.10] for boys, RR 1.32 [1.01-1.72] for girls), but with lower prevalence levels of cannabis use (RR 0.73 [95% CI 0.61-0.88]) and cigarette smoking (RR 0.79 [95% CI 0.70-0.89]) in girls alone. We also compared team sport athletes with high social involvement (sports team as primary peer group) and physical involvement (higher number of days/week physically active) to those with low involvement. For boys, the combination of high physical and high social involvement was associated with the highest risk, while high social involvement alone was associated with the greatest risk for girls. While team sport participation confers only a small increased risk for substance use, the prevalence of sport participation results in a large population impact. Given this fact, interventions such as education for parents and coaches and policies encouraging engagement in a variety of extracurricular activities should be explored.

The AGORA High-resolution Galaxy Simulations Comparison Project II: Isolated disk test

DOE PAGES

Kim, Ji-hoon; Agertz, Oscar; Teyssier, Romain; ...

2016-12-20

Using an isolated Milky Way-mass galaxy simulation, we compare results from 9 state-of-the-art gravito-hydrodynamics codes widely used in the numerical community. We utilize the infrastructure we have built for the AGORA High-resolution Galaxy Simulations Comparison Project. This includes the common disk initial conditions, common physics models (e.g., radiative cooling and UV background by the standardized package Grackle) and common analysis toolkit yt, all of which are publicly available. Subgrid physics models such as Jeans pressure floor, star formation, supernova feedback energy, and metal production are carefully constrained across code platforms. With numerical accuracy that resolves the disk scale height, wemore » find that the codes overall agree well with one another in many dimensions including: gas and stellar surface densities, rotation curves, velocity dispersions, density and temperature distribution functions, disk vertical heights, stellar clumps, star formation rates, and Kennicutt-Schmidt relations. Quantities such as velocity dispersions are very robust (agreement within a few tens of percent at all radii) while measures like newly-formed stellar clump mass functions show more significant variation (difference by up to a factor of ~3). Systematic differences exist, for example, between mesh-based and particle-based codes in the low density region, and between more diffusive and less diffusive schemes in the high density tail of the density distribution. Yet intrinsic code differences are generally small compared to the variations in numerical implementations of the common subgrid physics such as supernova feedback. Lastly, our experiment reassures that, if adequately designed in accordance with our proposed common parameters, results of a modern high-resolution galaxy formation simulation are more sensitive to input physics than to intrinsic differences in numerical schemes.« less

The AGORA High-resolution Galaxy Simulations Comparison Project II: Isolated disk test

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Ji-hoon; Agertz, Oscar; Teyssier, Romain

Using an isolated Milky Way-mass galaxy simulation, we compare results from 9 state-of-the-art gravito-hydrodynamics codes widely used in the numerical community. We utilize the infrastructure we have built for the AGORA High-resolution Galaxy Simulations Comparison Project. This includes the common disk initial conditions, common physics models (e.g., radiative cooling and UV background by the standardized package Grackle) and common analysis toolkit yt, all of which are publicly available. Subgrid physics models such as Jeans pressure floor, star formation, supernova feedback energy, and metal production are carefully constrained across code platforms. With numerical accuracy that resolves the disk scale height, wemore » find that the codes overall agree well with one another in many dimensions including: gas and stellar surface densities, rotation curves, velocity dispersions, density and temperature distribution functions, disk vertical heights, stellar clumps, star formation rates, and Kennicutt-Schmidt relations. Quantities such as velocity dispersions are very robust (agreement within a few tens of percent at all radii) while measures like newly-formed stellar clump mass functions show more significant variation (difference by up to a factor of ~3). Systematic differences exist, for example, between mesh-based and particle-based codes in the low density region, and between more diffusive and less diffusive schemes in the high density tail of the density distribution. Yet intrinsic code differences are generally small compared to the variations in numerical implementations of the common subgrid physics such as supernova feedback. Lastly, our experiment reassures that, if adequately designed in accordance with our proposed common parameters, results of a modern high-resolution galaxy formation simulation are more sensitive to input physics than to intrinsic differences in numerical schemes.« less

THE AGORA HIGH-RESOLUTION GALAXY SIMULATIONS COMPARISON PROJECT. II. ISOLATED DISK TEST

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Ji-hoon; Agertz, Oscar; Teyssier, Romain

Using an isolated Milky Way-mass galaxy simulation, we compare results from nine state-of-the-art gravito-hydrodynamics codes widely used in the numerical community. We utilize the infrastructure we have built for the AGORA High-resolution Galaxy Simulations Comparison Project. This includes the common disk initial conditions, common physics models (e.g., radiative cooling and UV background by the standardized package Grackle) and common analysis toolkit yt, all of which are publicly available. Subgrid physics models such as Jeans pressure floor, star formation, supernova feedback energy, and metal production are carefully constrained across code platforms. With numerical accuracy that resolves the disk scale height, wemore » find that the codes overall agree well with one another in many dimensions including: gas and stellar surface densities, rotation curves, velocity dispersions, density and temperature distribution functions, disk vertical heights, stellar clumps, star formation rates, and Kennicutt–Schmidt relations. Quantities such as velocity dispersions are very robust (agreement within a few tens of percent at all radii) while measures like newly formed stellar clump mass functions show more significant variation (difference by up to a factor of ∼3). Systematic differences exist, for example, between mesh-based and particle-based codes in the low-density region, and between more diffusive and less diffusive schemes in the high-density tail of the density distribution. Yet intrinsic code differences are generally small compared to the variations in numerical implementations of the common subgrid physics such as supernova feedback. Our experiment reassures that, if adequately designed in accordance with our proposed common parameters, results of a modern high-resolution galaxy formation simulation are more sensitive to input physics than to intrinsic differences in numerical schemes.« less

Treating Small Bowel Obstruction with a Manual Physical Therapy: A Prospective Efficacy Study

PubMed Central

Rice, Amanda D.; Patterson, Kimberley; Reed, Evette D.; Wurn, Belinda F.; Klingenberg, Bernhard; King, C. Richard; Wurn, Lawrence J.

2016-01-01

Small bowel obstructions (SBOs) caused by adhesions are a common, often life-threatening postsurgical complication with few treatment options available for patients. This study examines the efficacy of a manual physical therapy treatment regimen on the pain and quality of life of subjects with a history of bowel obstructions due to adhesions in a prospective, controlled survey based study. Changes in six domains of quality of life were measured via ratings reported before and after treatment using the validated Small Bowel Obstruction Questionnaire (SBO-Q). Improvements in the domains for pain (p = 0.0087), overall quality of life (p = 0.0016), and pain severity (p = 0.0006) were significant when average scores before treatment were compared with scores after treatment. The gastrointestinal symptoms (p = 0.0258) domain was marginally significant. There was no statistically significant improvement identified in the diet or medication domains in the SBO-Q for this population. Significant improvements in range of motion in the trunk (p ≤ 0.001), often limited by adhesions, were also observed for all measures. This study demonstrates in a small number of subjects that this manual physical therapy protocol is an effective treatment option for patients with adhesive small bowel obstructions as measured by subject reported symptoms and quality of life. PMID:26989690

Density-functional theory of spherical electric double layers and zeta potentials of colloidal particles in restricted-primitive-model electrolyte solutions.

PubMed

Yu, Yang-Xin; Wu, Jianzhong; Gao, Guang-Hua

2004-04-15

A density-functional theory is proposed to describe the density profiles of small ions around an isolated colloidal particle in the framework of the restricted primitive model where the small ions have uniform size and the solvent is represented by a dielectric continuum. The excess Helmholtz energy functional is derived from a modified fundamental measure theory for the hard-sphere repulsion and a quadratic functional Taylor expansion for the electrostatic interactions. The theoretical predictions are in good agreement with the results from Monte Carlo simulations and from previous investigations using integral-equation theory for the ionic density profiles and the zeta potentials of spherical particles at a variety of solution conditions. Like the integral-equation approaches, the density-functional theory is able to capture the oscillatory density profiles of small ions and the charge inversion (overcharging) phenomena for particles with elevated charge density. In particular, our density-functional theory predicts the formation of a second counterion layer near the surface of highly charged spherical particle. Conversely, the nonlinear Poisson-Boltzmann theory and its variations are unable to represent the oscillatory behavior of small ion distributions and charge inversion. Finally, our density-functional theory predicts charge inversion even in a 1:1 electrolyte solution as long as the salt concentration is sufficiently high. (c) 2004 American Institute of Physics.

Promoting Physical Understanding through Peer Mentoring

NASA Astrophysics Data System (ADS)

Nossal, S. M.; Huesmann, A.; Hooper, E.; Moore, C.; Watson, L.; Trestrail, A.; Weber, J.; Timbie, P.; Jacob, A.

2015-12-01

The Physics Learning Center at the University of Wisconsin-Madison provides a supportive learning community for students studying introductory physics, as well as teaching and leadership experience for undergraduate Peer Mentor Tutors who receive extensive training and supervision. Many of our Peer Tutors were former Physics Learning Center participants. A central goal of the Physics Learning Center is to address achievement/equity gaps (e.g. race, gender, socio-economic status, disability, age, transfer status, etc.) for undergraduate students pursuing majors and coursework in STEM fields. Students meet twice a week in small learning teams of 3-8 students, facilitated by a trained Peer Mentor Tutor or staff member. These active learning teams focus on discussing core physical concepts and practicing problem-solving. The weekly training of the tutors addresses both teaching and mentoring issues in science education such as helping students to build confidence, strategies for assessing student understanding, and fostering a growth mindset. A second weekly training meeting addresses common misconceptions and strategies for teaching specific physics topics. For non-science majors we have a small Peer Mentor Tutor program for Physics in the Arts. We will discuss the Physics Learning Center's approaches to promoting inclusion, understanding, and confidence for both our participants and Peer Mentor Tutors, as well as examples from the geosciences that can be used to illustrate introductory physics concepts.

Fiber Bragg Grating Sensors for Harsh Environments

PubMed Central

Mihailov, Stephen J.

2012-01-01

Because of their small size, passive nature, immunity to electromagnetic interference, and capability to directly measure physical parameters such as temperature and strain, fiber Bragg grating sensors have developed beyond a laboratory curiosity and are becoming a mainstream sensing technology. Recently, high temperature stable gratings based on regeneration techniques and femtosecond infrared laser processing have shown promise for use in extreme environments such as high temperature, pressure or ionizing radiation. Such gratings are ideally suited for energy production applications where there is a requirement for advanced energy system instrumentation and controls that are operable in harsh environments. This paper will present a review of some of the more recent developments. PMID:22438744

[INVITED] Laser-induced forward transfer: A high resolution additive manufacturing technology

NASA Astrophysics Data System (ADS)

Delaporte, Philippe; Alloncle, Anne-Patricia

2016-04-01

Among the additive manufacturing techniques, laser-induced forward transfer addresses the challenges of printing thin films in solid phase or small volume droplets in liquid phase with very high resolution. This paper reviews the physics of this process and explores the pros and cons of this technology versus other digital printing technologies. The main field of applications are printed electronics, organic electronics and tissue engineering, and the most promising short terms ones concern digital laser printing of sensors and conductive tracks. Future directions and emerging areas of interest are discussed such as printing solid from a liquid phase and 3D digital nanomanufacturing.

Large-Deformation Displacement Transfer Functions for Shape Predictions of Highly Flexible Slender Aerospace Structures

NASA Technical Reports Server (NTRS)

Ko, William L.; Fleischer, Van Tran

2013-01-01

Large deformation displacement transfer functions were formulated for deformed shape predictions of highly flexible slender structures like aircraft wings. In the formulation, the embedded beam (depth wise cross section of structure along the surface strain sensing line) was first evenly discretized into multiple small domains, with surface strain sensing stations located at the domain junctures. Thus, the surface strain (bending strains) variation within each domain could be expressed with linear of nonlinear function. Such piecewise approach enabled piecewise integrations of the embedded beam curvature equations [classical (Eulerian), physical (Lagrangian), and shifted curvature equations] to yield closed form slope and deflection equations in recursive forms.

Screen time and passive school travel as independent predictors of cardiorespiratory fitness in youth.

PubMed

Sandercock, Gavin R H; Ogunleye, Ayodele A

2012-05-01

The most prevalent sedentary behaviours in children and adolescents are engagement with small screen media (screen-time) and passive travel (by motorised vehicle). The objective of this research was to assess the independence of these behaviours from one another and from physical activity as predictors of cardiorespiratory fitness in youth. We measured cardiorespiratory fitness in n=6819 10-16 year olds (53% male) who self-reported their physical activity (7-day recall) school travel and screen time habits. Travel was classified as active (walking, cycling) or passive; screen time as <2 h, 2-4 h or >4 h. The multivariate odds of being fit were higher in active travel (Boys: OR 1.32, 95% CI: 1.09-1.59; Girls: OR 1.46, 1.15-1.84) than in passive travel groups. Boys reporting low screen time were more likely to be fit than those reporting >4 h (OR 2.11, 95% CI: 1.68-2.63) as were girls (OR 1.66, 95% CI: 1.24-2.20). These odds remained significant after additionally controlling for physical activity. Passive travel and high screen time are independently associated with poor cardiorespiratory fitness in youth, and this relationship is independent of physical activity levels. A lifestyle involving high screen time and habitual passive school travel appears incompatible with healthful levels of cardiorespiratory fitness in youth. Copyright © 2012 Elsevier Inc. All rights reserved.

Current advances in molecular imaging: noninvasive in vivo bioluminescent and fluorescent optical imaging in cancer research.

PubMed

Choy, Garry; Choyke, Peter; Libutti, Steven K

2003-10-01

Recently, there has been tremendous interest in developing techniques such as MRI, micro-CT, micro-PET, and SPECT to image function and processes in small animals. These technologies offer deep tissue penetration and high spatial resolution, but compared with noninvasive small animal optical imaging, these techniques are very costly and time consuming to implement. Optical imaging is cost-effective, rapid, easy to use, and can be readily applied to studying disease processes and biology in vivo. In vivo optical imaging is the result of a coalescence of technologies from chemistry, physics, and biology. The development of highly sensitive light detection systems has allowed biologists to use imaging in studying physiological processes. Over the last few decades, biochemists have also worked to isolate and further develop optical reporters such as GFP, luciferase, and cyanine dyes. This article reviews the common types of fluorescent and bioluminescent optical imaging, the typical system platforms and configurations, and the applications in the investigation of cancer biology.

Extremotolerant tardigrade genome and improved radiotolerance of human cultured cells by tardigrade-unique protein

PubMed Central

Hashimoto, Takuma; Horikawa, Daiki D.; Saito, Yuki; Kuwahara, Hirokazu; Kozuka-Hata, Hiroko; Shin-I, Tadasu; Minakuchi, Yohei; Ohishi, Kazuko; Motoyama, Ayuko; Aizu, Tomoyuki; Enomoto, Atsushi; Kondo, Koyuki; Tanaka, Sae; Hara, Yuichiro; Koshikawa, Shigeyuki; Sagara, Hiroshi; Miura, Toru; Yokobori, Shin-ichi; Miyagawa, Kiyoshi; Suzuki, Yutaka; Kubo, Takeo; Oyama, Masaaki; Kohara, Yuji; Fujiyama, Asao; Arakawa, Kazuharu; Katayama, Toshiaki; Toyoda, Atsushi; Kunieda, Takekazu

2016-01-01

Tardigrades, also known as water bears, are small aquatic animals. Some tardigrade species tolerate almost complete dehydration and exhibit extraordinary tolerance to various physical extremes in the dehydrated state. Here we determine a high-quality genome sequence of Ramazzottius varieornatus, one of the most stress-tolerant tardigrade species. Precise gene repertoire analyses reveal the presence of a small proportion (1.2% or less) of putative foreign genes, loss of gene pathways that promote stress damage, expansion of gene families related to ameliorating damage, and evolution and high expression of novel tardigrade-unique proteins. Minor changes in the gene expression profiles during dehydration and rehydration suggest constitutive expression of tolerance-related genes. Using human cultured cells, we demonstrate that a tardigrade-unique DNA-associating protein suppresses X-ray-induced DNA damage by ∼40% and improves radiotolerance. These findings indicate the relevance of tardigrade-unique proteins to tolerability and tardigrades could be a bountiful source of new protection genes and mechanisms. PMID:27649274

Proposal for a novel type of small scale aneutronic fusion reactor

NASA Astrophysics Data System (ADS)

Gruenwald, J.

2017-02-01

The aim of this work is to propose a novel scheme for a small scale aneutronic fusion reactor. This new reactor type makes use of the advantages of combining laser driven plasma acceleration and electrostatic confinement fusion. An intense laser beam is used to create a lithium-proton plasma with high density, which is then collimated and focused into the centre of the fusion reaction chamber. The basic concept presented here is based on the 7Li-proton fusion reaction. However, the physical and technological fundamentals may generally as well be applied to 11B-proton fusion. The former fusion reaction path offers higher energy yields while the latter has larger fusion cross sections. Within this paper a technological realisation of such a fusion device, which allows a steady state operation with highly energetic, well collimated ion beam, is presented. It will be demonstrated that the energetic break even can be reached with this device by using a combination of already existing technologies.

Extremotolerant tardigrade genome and improved radiotolerance of human cultured cells by tardigrade-unique protein.

PubMed

Hashimoto, Takuma; Horikawa, Daiki D; Saito, Yuki; Kuwahara, Hirokazu; Kozuka-Hata, Hiroko; Shin-I, Tadasu; Minakuchi, Yohei; Ohishi, Kazuko; Motoyama, Ayuko; Aizu, Tomoyuki; Enomoto, Atsushi; Kondo, Koyuki; Tanaka, Sae; Hara, Yuichiro; Koshikawa, Shigeyuki; Sagara, Hiroshi; Miura, Toru; Yokobori, Shin-Ichi; Miyagawa, Kiyoshi; Suzuki, Yutaka; Kubo, Takeo; Oyama, Masaaki; Kohara, Yuji; Fujiyama, Asao; Arakawa, Kazuharu; Katayama, Toshiaki; Toyoda, Atsushi; Kunieda, Takekazu

2016-09-20

Tardigrades, also known as water bears, are small aquatic animals. Some tardigrade species tolerate almost complete dehydration and exhibit extraordinary tolerance to various physical extremes in the dehydrated state. Here we determine a high-quality genome sequence of Ramazzottius varieornatus, one of the most stress-tolerant tardigrade species. Precise gene repertoire analyses reveal the presence of a small proportion (1.2% or less) of putative foreign genes, loss of gene pathways that promote stress damage, expansion of gene families related to ameliorating damage, and evolution and high expression of novel tardigrade-unique proteins. Minor changes in the gene expression profiles during dehydration and rehydration suggest constitutive expression of tolerance-related genes. Using human cultured cells, we demonstrate that a tardigrade-unique DNA-associating protein suppresses X-ray-induced DNA damage by ∼40% and improves radiotolerance. These findings indicate the relevance of tardigrade-unique proteins to tolerability and tardigrades could be a bountiful source of new protection genes and mechanisms.

EqualChance: Addressing Intra-set Write Variation to Increase Lifetime of Non-volatile Caches

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mittal, Sparsh; Vetter, Jeffrey S

To address the limitations of SRAM such as high-leakage and low-density, researchers have explored use of non-volatile memory (NVM) devices, such as ReRAM (resistive RAM) and STT-RAM (spin transfer torque RAM) for designing on-chip caches. A crucial limitation of NVMs, however, is that their write endurance is low and the large intra-set write variation introduced by existing cache management policies may further exacerbate this problem, thereby reducing the cache lifetime significantly. We present EqualChance, a technique to increase cache lifetime by reducing intra-set write variation. EqualChance works by periodically changing the physical cache-block location of a write-intensive data item withinmore » a set to achieve wear-leveling. Simulations using workloads from SPEC CPU2006 suite and HPC (high-performance computing) field show that EqualChance improves the cache lifetime by 4.29X. Also, its implementation overhead is small, and it incurs very small performance and energy loss.« less

Large & Small: Exploring the Laws of Nature

ERIC Educational Resources Information Center

Creutz, E.

1976-01-01

Illustrates how both large entities (such as stars and galaxies) and small entities (such as fundamental particles) obey the same physical laws. Discusses quantum mechanics, Newton's laws, and general relativity. (MLH)

Cross-linked lysozyme crystal templated synthesis of Au nanoparticles as high-performance recyclable catalysts.

PubMed

Liang, Miao; Wang, Libing; Liu, Xia; Qi, Wei; Su, Rongxin; Huang, Renliang; Yu, Yanjun; He, Zhimin

2013-06-21

Bio-nanomaterials fabricated using a bioinspired templating technique represent a novel class of composite materials with diverse applications in biomedical, electronic devices, drug delivery, and catalysis. In this study, Au nanoparticles (NPs) are synthesized within the solvent channels of cross-linked lysozyme crystals (CLLCs) in situ without the introduction of extra chemical reagents or physical treatments. The as-prepared AuNPs-in-protein crystal hybrid materials are characterized by light microscopy, transmission electron microscopy, x-ray diffraction, and Fourier-transform infrared spectroscopy analyses. Small AuNPs with narrow size distribution reveal the restriction effects of the porous structure in the lysozyme crystals. These composite materials are proven to be active heterogeneous catalysts for the reduction of 4-nitrophenol to 4-aminophenol. These catalysts can be easily recovered and reused at least 20 times because of the physical stability and macro-dimension of CLLCs. This work is the first to use CLLCs as a solid biotemplate for the preparation of recyclable high-performance catalysts.

Cross-linked lysozyme crystal templated synthesis of Au nanoparticles as high-performance recyclable catalysts

NASA Astrophysics Data System (ADS)

Liang, Miao; Wang, Libing; Liu, Xia; Qi, Wei; Su, Rongxin; Huang, Renliang; Yu, Yanjun; He, Zhimin

2013-06-01

Bio-nanomaterials fabricated using a bioinspired templating technique represent a novel class of composite materials with diverse applications in biomedical, electronic devices, drug delivery, and catalysis. In this study, Au nanoparticles (NPs) are synthesized within the solvent channels of cross-linked lysozyme crystals (CLLCs) in situ without the introduction of extra chemical reagents or physical treatments. The as-prepared AuNPs-in-protein crystal hybrid materials are characterized by light microscopy, transmission electron microscopy, x-ray diffraction, and Fourier-transform infrared spectroscopy analyses. Small AuNPs with narrow size distribution reveal the restriction effects of the porous structure in the lysozyme crystals. These composite materials are proven to be active heterogeneous catalysts for the reduction of 4-nitrophenol to 4-aminophenol. These catalysts can be easily recovered and reused at least 20 times because of the physical stability and macro-dimension of CLLCs. This work is the first to use CLLCs as a solid biotemplate for the preparation of recyclable high-performance catalysts.

Physical and chemical stratigraphy suggest small or absent glacioeustatic variation during formation of the Paradox Basin cyclothems

NASA Astrophysics Data System (ADS)

Dyer, Blake; Maloof, Adam C.

2015-06-01

The Paradox Basin cyclothems previously have been interpreted as Milankovitch style glacial-interglacial cycles from the Late Paleozoic Ice Age, but an unambiguous test for a glacioeustatic origin has not been conducted. A high resolution coupled chemical and physical stratigraphic analysis of two outcrop sections and three core segments provides new evidence that supports either minor sea level change of several meters or an autocyclic mechanism for parasequence formation. High amplitude sea level change is ruled out by the scale of thin top-negative isotopic meteoric diagenesis trends associated with parasequence tops and subaerial exposure fabrics. Isotopic gradients from shelf (light) to basin (heavy) indicate that parasequences are deposited diachronously, with isotopes of more distal sections recording increased basin restriction. These results support the idea that the late Pennsylvanian was a prolonged period of relatively static eustasy, agreeing with recent studies in the western USA. The methods provide a new set of tools and context for extracting environmental information from cyclic upward shallowing carbonate parasequences.

MICROROC: MICRO-mesh gaseous structure Read-Out Chip

NASA Astrophysics Data System (ADS)

Adloff, C.; Blaha, J.; Chefdeville, M.; Dalmaz, A.; Drancourt, C.; Dulucq, F.; Espargilière, A.; Gaglione, R.; Geffroy, N.; Jacquemier, J.; Karyotakis, Y.; Martin-Chassard, G.; Prast, J.; Seguin-Moreau, N.; de La Taille, Ch; Vouters, G.

2012-01-01

MICRO MEsh GAseous Structure (MICROMEGAS) and Gas Electron Multipliers (GEM) detectors are two candidates for the active medium of a Digital Hadronic CALorimeter (DHCAL) as part of a high energy physics experiment at a future linear collider (ILC/CLIC). Physics requirements lead to a highly granular hadronic calorimeter with up to thirty million channels with probably only hit information (digital readout calorimeter). To validate the concept of digital hadronic calorimetry with such small cell size, the construction and test of a cubic meter technological prototype, made of 40 planes of one square meter each, is necessary. This technological prototype would contain about 400 000 electronic channels, thus requiring the development of front-end ASIC. Based on the experience gained with previous ASIC that were mounted on detectors and tested in particle beams, a new ASIC called MICROROC has been developped. This paper summarizes the caracterisation campaign that was conducted on this new chip as well as its integration into a large area Micromegas chamber of one square meter.

Teacher, peer and parent autonomy support in physical education and leisure-time physical activity: A trans-contextual model of motivation in four nations.

PubMed

Hagger, Martin; Chatzisarantis, Nikos L D; Hein, Vello; Soós, István; Karsai, István; Lintunen, Taru; Leemans, Sofie

2009-07-01

An extended trans-contextual model of motivation for health-related physical activity was tested in samples from four nations. The model proposes a motivational sequence in which perceived autonomy support from teachers in a physical education (PE) context and from peers and parents in a leisure-time physical activity context predict autonomous motivation, intentions and physical activity behaviour in a leisure-time context. A three-wave prospective correlational design was employed. High-school pupils from Britain, Estonia, Finland and Hungary completed measures of perceived autonomy support from PE teachers, autonomous motivation in both contexts, perceived autonomy support from peers and parents, attitudes, subjective norms, perceived behavioural control and intentions from the Theory of Planned Behaviour (TPB), and measures of behaviour and past behaviour in a leisure-time context. Path-analyses controlling for past behaviour supported trans-contextual model hypotheses across all samples. Effects of perceived autonomy support from peers and parents on leisure-time autonomous motivation were small and inconsistent, while effects on TPB variables were stronger. There was a unique effect of perceived autonomy support from PE teachers on leisure-time autonomous motivation. Findings support the model, which provides an explanation of the processes by which perceived autonomy support from different sources affects health-related physical activity motivation across these contexts.

Metabolic profile in two physically active Inuit groups consuming either a western or a traditional Inuit diet.

PubMed

Munch-Andersen, Thor; Olsen, David B; Søndergaard, Hans; Daugaard, Jens R; Bysted, Anette; Christensen, Dirk L; Saltin, Bengt; Helge, Jørn W

2012-03-19

To evaluate the effect of regular physical activity on metabolic risk factors and blood pressure in Inuit with high BMI consuming a western diet (high amount of saturated fatty acids and carbohydrates with a high glycemic index). Cross sectional study, comparing Inuit eating a western diet with Inuit eating a traditional diet. Two physically active Greenland Inuit groups consuming different diet, 20 eating a traditional diet (Qaanaaq) and 15 eating a western diet (TAB), age (mean (range)); 38, (22-58) yrs, BMI; 28 (20-40) were subjected to an oral glucose tolerance test (OGTT), blood sampling, maximal oxygen uptake test, food interview/collection and monitoring of physical activity. All Inuit had a normal OGTT. Fasting glucose (mmol/l), HbA1c (%), total cholesterol (mmol/l) and HDL-C (mmol/l) were for Qaanaaq women: 4.8±0.2, 5.3±0.1, 4.96±0.42, 1.34±0.06, for Qaanaaq men: 4.9±0.1, 5.7±0.1, 5.08±0.31, 1.28±0.09, for TAB women: 5.1±0.2, 5.3±0.1, 6.22±0.39, 1.86±0.13, for TAB men: 5.1±0.2, 5.3±0.1, 6.23±0.15, 1.60±0.10. No differences were found in systolic or diastolic blood pressure between the groups. There was a more adverse distribution of small dense LDL-C particles and higher total cholesterol and HDL-C concentration in the western diet group. Diabetes or impaired glucose tolerance was not found in the Inuit consuming either the western or the traditional diet, and this could, at least partly, be due to the high amount of regular daily physical activity. However, when considering the total cardio vascular risk profile the Inuit consuming a western diet had a less healthy profile than the Inuit consuming a traditional diet.

What are the Main Physical Functioning Factors Associated With Falls Among Older People With Different Perceived Fall Risk?

PubMed

Moreira, Mirian N; Bilton, Tereza L; Dias, Rosangela C; Ferriolli, Eduardo; Perracini, Monica R

2017-07-01

Fall risk perceptions may influence the judgement over physical and functional competencies to avoid falls. However, few studies have explored the physical functioning characteristics associated with falls among older people with low perceived fall risk. This study aimed to identify the prevalence of falls and physical functioning factors associated with falling among community-dwelling older adults with low and high perceived fall risk. We conducted a cross-sectional population based study with 773 community-dwelling elders. Perceived fall risk was investigated using Falls Efficacy Scale International. We considered fallers those who reported at least one fall in the previous 12 months. Physical functioning measures used were grip strength, usual gait speed, sit-to-stand test, five step test, timed up and go test, one-legged stance test, anterior and lateral functional reach test. At least one fall was reported by 103 (30%) participants with low perceived fall risk and by 196 (46%) participants with high perceived fall risk. The odds of falling were lower among those with greater grip strength and with a greater stance time in one-legged test, and the odds of falling among elders with high perceived fall risk were higher among those who took more time in performing the five step test. We believe that our results highlight the need of not neglecting the risk of falls among active older adults with low perceived fall risk, particularly in those elders that show reduced stability in a small base of support and a lower leg strength. In addition, we suggest that elders with high perceived fall risk should be assessed using anticipatory postural adjustment tests. Particularly, our results may help physiotherapists to identify eligible elders with different perceptions of fall risk for tailored interventions aimed at reducing falls. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Effect of Long-Term Physical Activity Practice after Cardiac Rehabilitation on Some Risk Factors

ERIC Educational Resources Information Center

Freyssin, Celine, Jr.; Blanc, Philippe; Verkindt, Chantal; Maunier, Sebastien; Prieur, Fabrice

2011-01-01

The objective of this study was to evaluate the effects of long-term physical activity practice after a cardiac rehabilitation program on weight, physical capacity and arterial compliance. The Dijon Physical Activity Score was used to identify two groups: sedentary and active. Weight, distance at the 6-min walk test and the small artery elasticity…

Learning about a Level Physics Students' Understandings of Particle Physics Using Concept Mapping

ERIC Educational Resources Information Center

Gourlay, H.

2017-01-01

This paper describes a small-scale piece of research using concept mapping to elicit A level students' understandings of particle physics. Fifty-nine year 12 (16- and 17 year-old) students from two London schools participated. The exercise took place during school physics lessons. Students were instructed how to make a concept map and were…

13 CFR 123.203 - What interest rate will my business pay on a physical disaster business loan and what are the...

Code of Federal Regulations, 2012 CFR

2012-01-01

... business pay on a physical disaster business loan and what are the repayment terms? 123.203 Section 123.203 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.203 What interest rate will my business pay on a physical disaster business loan and...

13 CFR 123.203 - What interest rate will my business pay on a physical disaster business loan and what are the...

Code of Federal Regulations, 2013 CFR

2013-01-01

... business pay on a physical disaster business loan and what are the repayment terms? 123.203 Section 123.203 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.203 What interest rate will my business pay on a physical disaster business loan and...

13 CFR 123.203 - What interest rate will my business pay on a physical disaster business loan and what are the...

Code of Federal Regulations, 2014 CFR

2014-01-01

... business pay on a physical disaster business loan and what are the repayment terms? 123.203 Section 123.203 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.203 What interest rate will my business pay on a physical disaster business loan and...

13 CFR 123.203 - What interest rate will my business pay on a physical disaster business loan and what are the...

Code of Federal Regulations, 2011 CFR

2011-01-01

... business pay on a physical disaster business loan and what are the repayment terms? 123.203 Section 123.203 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION DISASTER LOAN PROGRAM Physical Disaster Business Loans § 123.203 What interest rate will my business pay on a physical disaster business loan and...

Gradient-Type Magnetoelectric Current Sensor with Strong Multisource Noise Suppression.

PubMed

Zhang, Mingji; Or, Siu Wing

2018-02-14

A novel gradient-type magnetoelectric (ME) current sensor operating in magnetic field gradient (MFG) detection and conversion mode is developed based on a pair of ME composites that have a back-to-back capacitor configuration under a baseline separation and a magnetic biasing in an electrically-shielded and mechanically-enclosed housing. The physics behind the current sensing process is the product effect of the current-induced MFG effect associated with vortex magnetic fields of current-carrying cables (i.e., MFG detection) and the MFG-induced ME effect in the ME composite pair (i.e., MFG conversion). The sensor output voltage is directly obtained from the gradient ME voltage of the ME composite pair and is calibrated against cable current to give the current sensitivity. The current sensing performance of the sensor is evaluated, both theoretically and experimentally, under multisource noises of electric fields, magnetic fields, vibrations, and thermals. The sensor combines the merits of small nonlinearity in the current-induced MFG effect with those of high sensitivity and high common-mode noise rejection rate in the MFG-induced ME effect to achieve a high current sensitivity of 0.65-12.55 mV/A in the frequency range of 10 Hz-170 kHz, a small input-output nonlinearity of <500 ppm, a small thermal drift of <0.2%/℃ in the current range of 0-20 A, and a high common-mode noise rejection rate of 17-28 dB from multisource noises.

Gradient-Type Magnetoelectric Current Sensor with Strong Multisource Noise Suppression

PubMed Central

2018-01-01

A novel gradient-type magnetoelectric (ME) current sensor operating in magnetic field gradient (MFG) detection and conversion mode is developed based on a pair of ME composites that have a back-to-back capacitor configuration under a baseline separation and a magnetic biasing in an electrically-shielded and mechanically-enclosed housing. The physics behind the current sensing process is the product effect of the current-induced MFG effect associated with vortex magnetic fields of current-carrying cables (i.e., MFG detection) and the MFG-induced ME effect in the ME composite pair (i.e., MFG conversion). The sensor output voltage is directly obtained from the gradient ME voltage of the ME composite pair and is calibrated against cable current to give the current sensitivity. The current sensing performance of the sensor is evaluated, both theoretically and experimentally, under multisource noises of electric fields, magnetic fields, vibrations, and thermals. The sensor combines the merits of small nonlinearity in the current-induced MFG effect with those of high sensitivity and high common-mode noise rejection rate in the MFG-induced ME effect to achieve a high current sensitivity of 0.65–12.55 mV/A in the frequency range of 10 Hz–170 kHz, a small input-output nonlinearity of <500 ppm, a small thermal drift of <0.2%/℃ in the current range of 0–20 A, and a high common-mode noise rejection rate of 17–28 dB from multisource noises. PMID:29443920

Physical chemistry of Nanogap-Enhanced Raman Scattering (NERS)

NASA Astrophysics Data System (ADS)

Suh, Yung Doug; Kim, Hyun Woo

2017-08-01

Plasmonically coupled electromagnetic field localization has generated a variety of new concepts and applications, and this has been one of the hottest topics in nanoscience, materials science, chemistry, physics and engineering and increasingly more important over the last decade. In particular, plasmonically coupled nanostructures with ultra-small gap ( 1-nm or smaller) gap have been of special interest due to their ultra-strong optical properties that can be useful for a variety of signal enhancements such surface-enhanced Raman scattering (SERS) and nanoantenna. These promising nanostructures with extraordinarily strong optical signal, however, have rendered a limited success in widespread use and commercialization largely due to the lack of designing principles, high-yield synthetic strategies with nm-level structural controllability and reproducibility and lack of systematic single-molecule and single-particle level studies. All these are extremely important challenges because even small changes ( 1 nm) of the coupled nanogap structures can significant affect plasmon mode and signal intensity and therefore structural and signal reproducibility and controllability can be in question. The plasmonic nanogap-enhanced Raman scattering (NERS) is defined as the plasmonic nanogap-based Raman signal enhancement within plasmonic nanogap particles with 1 nm gap and a Raman dye positioned inside the gap.

Characteristics of solitary waves in a relativistic degenerate ion beam driven magneto plasma

NASA Astrophysics Data System (ADS)

Deka, Manoj Kr.; Dev, Apul N.; Misra, Amar P.; Adhikary, Nirab C.

2018-01-01

The nonlinear propagation of a small amplitude ion acoustic solitary wave in a relativistic degenerate magneto plasma in the presence of an ion beam is investigated in detail. The nonlinear equations describing the evolution of a solitary wave in the presence of relativistic non-degenerate magnetized positive ions and ion beams including magnetized degenerate relativistic electrons are derived in terms of Zakharov-Kuznetsov (Z-K) equation for such plasma systems. The ion beams which are a ubiquitous ingredient in such plasma systems are found to have a decisive role in the propagation of a solitary wave in such a highly dense plasma system. The conditions of a wave, propagating with typical solitonic characteristics, are examined and discussed in detail under suitable conditions of different physical parameters. Both a subsonic and supersonic wave can propagate in such plasmas bearing different characteristics under different physical situations. A detailed analysis of waves propagating in subsonic and/or supersonic regime is carried out. The ion beam concentrations, magnetic field, as well as ion beam streaming velocity are found to play a momentous role on the control of the amplitude and width of small amplitude perturbation in both weakly (or non-relativistic) and relativistic plasmas.

AX-GADGET: a new code for cosmological simulations of Fuzzy Dark Matter and Axion models

NASA Astrophysics Data System (ADS)

Nori, Matteo; Baldi, Marco

2018-05-01

We present a new module of the parallel N-Body code P-GADGET3 for cosmological simulations of light bosonic non-thermal dark matter, often referred as Fuzzy Dark Matter (FDM). The dynamics of the FDM features a highly non-linear Quantum Potential (QP) that suppresses the growth of structures at small scales. Most of the previous attempts of FDM simulations either evolved suppressed initial conditions, completely neglecting the dynamical effects of QP throughout cosmic evolution, or resorted to numerically challenging full-wave solvers. The code provides an interesting alternative, following the FDM evolution without impairing the overall performance. This is done by computing the QP acceleration through the Smoothed Particle Hydrodynamics (SPH) routines, with improved schemes to ensure precise and stable derivatives. As an extension of the P-GADGET3 code, it inherits all the additional physics modules implemented up to date, opening a wide range of possibilities to constrain FDM models and explore its degeneracies with other physical phenomena. Simulations are compared with analytical predictions and results of other codes, validating the QP as a crucial player in structure formation at small scales.

Optical and chemical characterization of aerosols emitted from coal, heavy and light fuel oil, and small-scale wood combustion.

PubMed

Frey, Anna K; Saarnio, Karri; Lamberg, Heikki; Mylläri, Fanni; Karjalainen, Panu; Teinilä, Kimmo; Carbone, Samara; Tissari, Jarkko; Niemelä, Ville; Häyrinen, Anna; Rautiainen, Jani; Kytömäki, Jorma; Artaxo, Paulo; Virkkula, Aki; Pirjola, Liisa; Rönkkö, Topi; Keskinen, Jorma; Jokiniemi, Jorma; Hillamo, Risto

2014-01-01

Particle emissions affect radiative forcing in the atmosphere. Therefore, it is essential to know the physical and chemical characteristics of them. This work studied the chemical, physical, and optical characteristics of particle emissions from small-scale wood combustion, coal combustion of a heating and power plant, as well as heavy and light fuel oil combustion at a district heating station. Fine particle (PM1) emissions were the highest in wood combustion with a high fraction of absorbing material. The emissions were lowest from coal combustion mostly because of efficient cleaning techniques used at the power plant. The chemical composition of aerosols from coal and oil combustion included mostly ions and trace elements with a rather low fraction of absorbing material. The single scattering albedo and aerosol forcing efficiency showed that primary particles emitted from wood combustion and some cases of oil combustion would have a clear climate warming effect even over dark earth surfaces. Instead, coal combustion particle emissions had a cooling effect. Secondary processes in the atmosphere will further change the radiative properties of these emissions but are not considered in this study.

Effectiveness of a Worksite Social & Physical Environment Intervention on Need for Recovery, Physical Activity and Relaxation; Results of a Randomized Controlled Trial

PubMed Central

Coffeng, Jennifer K.; Boot, Cécile R. L.; Duijts, Saskia F. A.; Twisk, Jos W. R.; van Mechelen, Willem; Hendriksen, Ingrid J. M.

2014-01-01

Objective To investigate the effectiveness of a worksite social and physical environment intervention on need for recovery (i.e., early symptoms of work-related mental and physical fatigue), physical activity and relaxation. Also, the effectiveness of the separate interventions was investigated. Methods In this 2×2 factorial design study, 412 office employees from a financial service provider participated. Participants were allocated to the combined social and physical intervention, to the social intervention only, to the physical intervention only or to the control group. The primary outcome measure was need for recovery. Secondary outcomes were work-related stress (i.e., exhaustion, detachment and relaxation), small breaks, physical activity (i.e., stair climbing, active commuting, sport activities, light/moderate/vigorous physical activity) and sedentary behavior. Outcomes were measured by questionnaires at baseline, 6 and 12 months follow-up. Multilevel analyses were performed to investigate the effects of the three interventions. Results In all intervention groups, a non-significant reduction was found in need for recovery. In the combined intervention (n = 92), exhaustion and vigorous physical activities decreased significantly, and small breaks at work and active commuting increased significantly compared to the control group. The social intervention (n = 118) showed a significant reduction in exhaustion, sedentary behavior at work and a significant increase in small breaks at work and leisure activities. In the physical intervention (n = 96), stair climbing at work and active commuting significantly increased, and sedentary behavior at work decreased significantly compared to the control group. Conclusion None of the interventions was effective in improving the need for recovery. It is recommended to implement the social and physical intervention among a population with higher baseline values of need for recovery. Furthermore, the intervention itself could be improved by increasing the intensity of the intervention (for example weekly GMI-sessions), providing physical activity opportunities and exercise schemes, and by more drastic environment interventions (restructuring entire department floor). Trial Registration Nederlands Trial Register NTR2553 PMID:25542039

Purposes of Physical Education - Today and Tomorrow.

ERIC Educational Resources Information Center

LaPlante, Marilyn

The emphasis in physical education appears to be changing toward a more humanistic education to counteract a dehumanizing trend with the emphasis on mechanization, efficiency, and technological innovation. This paper includes the results from a small survey of physical educators representing five groups: (1) curriculum theorists, (2) researchers,…

Community-Based Culturally Preferred Physical Activity Intervention Targeting Populations at High Risk for Type 2 Diabetes: Results and Implications.

PubMed

Rowan, Chip P; Riddell, Michael C; Gledhill, Norman; Jamnik, Veronica K

2016-12-01

In Canada, an ageing population, obesity rates and high risk among certain ethnocultural populations are driving diabetes prevalence. Given the burden associated with type 2 diabetes and its link to modifiable risk factors, this study aimed to implement culturally preferred physical activities at the community level, targeting individuals at high risk for type 2 diabetes. Glycated hemoglobin (A1C) levels were used to detect potential improvements in glycemic control. Participants were screened for diabetes risk using a questionnaire and capillary point-of-care A1C blood testing. Participants were offered community-based physical activity classes 2 to 3 times per week for 6 months. A subset of participants (n=84) provided additional measurements. In total, 718 subjects were reached during recruitment. Substantial participant dropout took place, and 487 participants were exposed to the intervention. Among those who participated in the physical activity and provided follow up, mean A1C levels were reduced by 0.17 (p=0.002) after 3 months (n=84) and by 0.06 (p=0.35; n=49) after 6 months. The homeostatic model assessment (HOMA-beta) showed a significant improvement of 23.6% after 3 months (n=20; p=0.03) and 45.2% after 6 months (n=12; p=0.02). Resting systolic blood pressure and diastolic blood pressure plus combined hand-grip strength improved after 6 months (n=12). Implementation of this community-based, culturally preferred physical activity program presented several challenges and was associated with significant participant dropout. After considering participant dropout, the relatively small group who participated and provided follow-up measures showed improvements various physiologic measures. Despite efforts to enhance accessibility, it appears that several barriers to physical activity participation remain and need to be explored to enhance the success of future programs. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

Reversible and long-term immobilization in a hydrogel-microbead matrix for high-resolution imaging of Caenorhabditis elegans and other small organisms

PubMed Central

Cornaglia, Matteo; Krishnamani, Gopalan; Zhang, Jingwei; Mouchiroud, Laurent; Lehnert, Thomas; Auwerx, Johan; Gijs, Martin A. M.

2018-01-01

The nematode Caenorhabditis elegans is an important model organism for biomedical research and genetic studies relevant to human biology and disease. Such studies are often based on high-resolution imaging of dynamic biological processes in the worm body tissues, requiring well-immobilized and physiologically active animals in order to avoid movement-related artifacts and to obtain meaningful biological information. However, existing immobilization methods employ the application of either anesthetics or servere physical constraints, by using glue or specific microfluidic on-chip mechanical structures, which in some cases may strongly affect physiological processes of the animals. Here, we immobilize C. elegans nematodes by taking advantage of a biocompatible and temperature-responsive hydrogel-microbead matrix. Our gel-based immobilization technique does not require a specific chip design and enables fast and reversible immobilization, thereby allowing successive imaging of the same single worm or of small worm populations at all development stages for several days. We successfully demonstrated the applicability of this method in challenging worm imaging contexts, in particular by applying it for high-resolution confocal imaging of the mitochondrial morphology in worm body wall muscle cells and for the long-term quantification of number and size of specific protein aggregates in different C. elegans neurodegenerative disease models. Our approach was also suitable for immobilizing other small organisms, such as the larvae of the fruit fly Drosophila melanogaster and the unicellular parasite Trypanosoma brucei. We anticipate that this versatile technique will significantly simplify biological assay-based longitudinal studies and long-term observation of small model organisms. PMID:29509812

Magnet Healing?

NASA Astrophysics Data System (ADS)

Finegold, Leonard

2000-03-01

Many people are convinced that static magnets—applied to their skin—will heal ills, and many businesses sell such magnets. The biophysics of such healing was reviewed [1] together with the general biophysics of static fields. Birds and insects do use the earth’s magnetic field for navigation. While insect and frog egg development can clearly be influenced by high fields (7 T and 17 T respectively), there is no experimental evidence that small magnetic fields (of less than 0.5 T) might heal, and much evidence that they cannot heal. A puzzle to the physics community is: How to show laypersons that simple magnets (very probably) do not heal, however attractive that idea might be. [1] L. Finegold, The Physics of "Alternative Medicine": Magnet Therapy, The Scientific Review of Alternative Medicine 3:26-33 (1999).

Associations between sedentary behaviour and physical activity in children and adolescents: a meta-analysis

PubMed Central

Pearson, N; Braithwaite, R E; Biddle, S J H; van Sluijs, E M F; Atkin, A J

2014-01-01

Physical activity and sedentary behaviour are associated with metabolic and mental health during childhood and adolescence. Understanding the inter-relationships between these behaviours will help to inform intervention design. This systematic review and meta-analysis synthesized evidence from observational studies describing the association between sedentary behaviour and physical activity in young people (<18 years). English-language publications up to August 2013 were located through electronic and manual searches. Included studies presented statistical associations between at least one measure of sedentary behaviour and one measure of physical activity. One hundred sixty-three papers were included in the meta-analysis, from which data on 254 independent samples was extracted. In the summary meta-analytic model (k = 230), a small, but significant, negative association between sedentary behaviour and physical activity was observed (r = −0.108, 95% confidence interval [CI] = −0.128, −0.087). In moderator analyses, studies that recruited smaller samples (n < 100, r = −0.193, 95% CI = −0.276, −0.109) employed objective methods of measurement (objectively measured physical activity; r = −0.233, 95% CI = −0.330, −0.137) or were assessed to be of higher methodological quality (r = −0.176, 95% CI = −0.215, −0.138) reported stronger associations, although effect sizes remained small. The association between sedentary behaviour and physical activity in young people is negative, but small, suggesting that these behaviours do not directly displace one another. PMID:24844784

Associations between sedentary behaviour and physical activity in children and adolescents: a meta-analysis.

PubMed

Pearson, N; Braithwaite, R E; Biddle, S J H; van Sluijs, E M F; Atkin, A J

2014-08-01

Physical activity and sedentary behaviour are associated with metabolic and mental health during childhood and adolescence. Understanding the inter-relationships between these behaviours will help to inform intervention design. This systematic review and meta-analysis synthesized evidence from observational studies describing the association between sedentary behaviour and physical activity in young people (<18 years). English-language publications up to August 2013 were located through electronic and manual searches. Included studies presented statistical associations between at least one measure of sedentary behaviour and one measure of physical activity. One hundred sixty-three papers were included in the meta-analysis, from which data on 254 independent samples was extracted. In the summary meta-analytic model (k = 230), a small, but significant, negative association between sedentary behaviour and physical activity was observed (r = -0.108, 95% confidence interval [CI] = -0.128, -0.087). In moderator analyses, studies that recruited smaller samples (n < 100, r = -0.193, 95% CI = -0.276, -0.109) employed objective methods of measurement (objectively measured physical activity; r = -0.233, 95% CI = -0.330, -0.137) or were assessed to be of higher methodological quality (r = -0.176, 95% CI = -0.215, -0.138) reported stronger associations, although effect sizes remained small. The association between sedentary behaviour and physical activity in young people is negative, but small, suggesting that these behaviours do not directly displace one another. © 2014 The Authors. Obesity Reviews published by John Wiley & Sons Ltd on behalf of International Association for the Study of Obesity.

Energetics, scaling and sexual size dimorphism of spiders.

PubMed

Grossi, B; Canals, M

2015-03-01

The extreme sexual size dimorphism in spiders has motivated studies for many years. In many species the male can be very small relative to the female. There are several hypotheses trying to explain this fact, most of them emphasizing the role of energy in determining spider size. The aim of this paper is to review the role of energy in sexual size dimorphism of spiders, even for those spiders that do not necessarily live in high foliage, using physical and allometric principles. Here we propose that the cost of transport or equivalently energy expenditure and the speed are traits under selection pressure in male spiders, favoring those of smaller size to reduce travel costs. The morphology of the spiders responds to these selective forces depending upon the lifestyle of the spiders. Climbing and bridging spiders must overcome the force of gravity. If bridging allows faster dispersal, small males would have a selective advantage by enjoying more mating opportunities. In wandering spiders with low population density and as a consequence few male-male interactions, high speed and low energy expenditure or cost of transport should be favored by natural selection. Pendulum mechanics show the advantages of long legs in spiders and their relationship with high speed, even in climbing and bridging spiders. Thus small size, compensated by long legs should be the expected morphology for a fast and mobile male spider.

Investigation of the spinfoam path integral with quantum cuboid intertwiners

NASA Astrophysics Data System (ADS)

Bahr, Benjamin; Steinhaus, Sebastian

2016-05-01

In this work, we investigate the 4d path integral for Euclidean quantum gravity on a hypercubic lattice, as given by the spinfoam model by Engle, Pereira, Rovelli, Livine, Freidel and Krasnov. To tackle the problem, we restrict to a set of quantum geometries that reflects the large amount of lattice symmetries. In particular, the sum over intertwiners is restricted to quantum cuboids, i.e. coherent intertwiners which describe a cuboidal geometry in the large-j limit. Using asymptotic expressions for the vertex amplitude, we find several interesting properties of the state sum. First of all, the value of coupling constants in the amplitude functions determines whether geometric or nongeometric configurations dominate the path integral. Secondly, there is a critical value of the coupling constant α , which separates two phases. In both phases, the diffeomorphism symmetry appears to be broken. In one, the dominant contribution comes from highly irregular, in the other from highly regular configurations, both describing flat Euclidean space with small quantum fluctuations around them, viewed in different coordinate systems. On the critical point diffeomorphism symmetry is nearly restored, however. Thirdly, we use the state sum to compute the physical norm of kinematical states, i.e. their norm in the physical Hilbert space. We find that states which describe boundary geometry with high torsion have an exponentially suppressed physical norm. We argue that this allows one to exclude them from the state sum in calculations.

TH-EF-204-02: Small Field Radiation Therapy: Physics and Recent Recommendations From IAEA and ICRU

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seuntjens, J.

Joanna E. Cygler, Jan Seuntjens, J. Daniel Bourland, M. Saiful Huq, Josep Puxeu Vaque, Daniel Zucca Aparicio, Tatiana Krylova, Yuri Kirpichev, Eric Ford, Caridad Borras Stereotactic Radiation Therapy (SRT) utilizes small static and dynamic (IMRT) fields, to successfully treat malignant and benign diseases using techniques such as Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiation Therapy (SBRT). SRT is characterized by sharp dose gradients for individual fields and their resultant dose distributions. For appropriate targets, small field radiotherapy offers improved treatment quality by allowing better sparing of organs at risk while delivering the prescribed target dose. Specialized small field treatment deliverymore » systems, such as robotic-controlled linear accelerators, gamma radiosurgery units, and dynamic arc linear accelerators may utilize rigid fixation, image guidance, and tumor tracking, to insure precise dose delivery to static or moving targets. However, in addition to great advantages, small field delivery techniques present special technical challenges for dose calibration due to unique geometries and small field sizes not covered by existing reference dosimetry protocols such as AAPM TG-51 or IAEA TRS 398. In recent years extensive research has been performed to understand small field dosimetry and measurement instrumentation. AAPM, IAEA and ICRU task groups are expected to provide soon recommendations on the dosimetry of small radiation fields. In this symposium we will: 1] discuss the physics, instrumentation, methodologies and challenges for small field radiation dose measurements; 2] review IAEA and ICRU recommendations on prescribing, recording and reporting of small field radiation therapy; 3] discuss selected clinical applications and technical aspects for specialized image-guided, small field, linear accelerator based treatment techniques such as IMRT and SBRT. Learning Objectives: To learn the physics of small fields in contrast to dosimetry of conventional fields To learn about detectors suitable for small fields To learn about the role of Monte Carlo simulations in determination of small field output factors To provide an overview of the IAEA small field dosimetry recommendations To provide an overview of the content of the ICRU report on Prescribing, Reporting and Recording of Small Field Radiation Therapy. To learn about special technical considerations in delivering IMRT and SBRT treatments To appreciate specific challenges of IMRT implementation J. Seuntjens, Natural Sciences and Engineering Research Council; Canadian Institutes of Health Research.« less

Enhanced flyby science with onboard computer vision: Tracking and surface feature detection at small bodies

NASA Astrophysics Data System (ADS)

Fuchs, Thomas J.; Thompson, David R.; Bue, Brian D.; Castillo-Rogez, Julie; Chien, Steve A.; Gharibian, Dero; Wagstaff, Kiri L.

2015-10-01

Spacecraft autonomy is crucial to increase the science return of optical remote sensing observations at distant primitive bodies. To date, most small bodies exploration has involved short timescale flybys that execute prescripted data collection sequences. Light time delay means that the spacecraft must operate completely autonomously without direct control from the ground, but in most cases the physical properties and morphologies of prospective targets are unknown before the flyby. Surface features of interest are highly localized, and successful observations must account for geometry and illumination constraints. Under these circumstances onboard computer vision can improve science yield by responding immediately to collected imagery. It can reacquire bad data or identify features of opportunity for additional targeted measurements. We present a comprehensive framework for onboard computer vision for flyby missions at small bodies. We introduce novel algorithms for target tracking, target segmentation, surface feature detection, and anomaly detection. The performance and generalization power are evaluated in detail using expert annotations on data sets from previous encounters with primitive bodies.

The right place for the right job in the photovoltaic life cycle.

PubMed

Kawajiri, Kotaro; Genchi, Yutaka

2012-07-03

The potential for photovoltaic power generation (PV) to reduce primary energy consumption (PEC) and CO(2) emissions depends on the physical locations of each stage of its life cycle. When stages are optimally located, CO(2) emissions are reduced nearly ten times as much as when each stage is located in the country having the largest current market share. The usage stage contributes the most to reducing CO(2) emissions and PEC, and total CO(2) emissions actually increase when PV is installed in countries having small CO(2) emissions from electricity generation. Global maps of CO(2) reduction potential indicate that Botswana and Gobi in Mongolia are the optimal locations to install PV due to favorable conditions for PV power generation and high CO(2) emissions from current electricity generation. However, the small electricity demand in those countries limits the contribution to global CO(2) reduction. The type of PVs has a small but significant effect on life cycle PEC and CO(2) emissions.

Ultra-small single-negative electric metamaterials for electromagnetic coupling reduction of microstrip antenna array.

PubMed

Xu, He-Xiu; Wang, Guang-Ming; Qi, Mei-Qing; Zeng, Hui-Yong

2012-09-24

We report initially the design, fabrication and measurement of using waveguided electric metamaterials (MTM) in the design of closely-spaced microtrip antenna arrays with mutual coupling reduction. The complementary spiral ring resonators (CSRs) which exhibit single negative resonant permittivity around 3.5GHz are used as the basic electric MTM element. For verification, two CSRs with two and three concentric rings are considered, respectively. By properly arranging these well engineered waveguided MTMs between two H-plane coupled patch antennas, both numerical and measured results indicate that more than 8.4 dB mutual coupling reduction is obtained. The mechanism has been studied from a physical insight. The electric MTM element is electrically small, enabling the resultant antenna array to exhibit a small separation (λo/8 at the operating wavelength) and thus a high directivity. The proposed strategy opens an avenue to new types of antenna with super performances and can be generalized for other electric resonators.

Randomised controlled trial of informal team sports for cardiorespiratory fitness and health benefit in Pacific adults.

PubMed

Biddle, Mark G; Vincent, Grace; McCambridge, Alana; Britton, Gabrielle; Dewes, Ofa; Elley, C Raina; Moyes, Simon A; Edge, Johann

2011-12-01

Rates of obesity, Type 2 diabetes and cardiovascular disease are high among Pacific people in New Zealand. Physical activity is recommended in the prevention and management of these conditions. Community-based, 'small-sided game' group activities may be an effective and culturally appropriate way to promote physical activity within Pacific communities. To assess the effectiveness of small-sided games-based exercise on fitness and health parameters among Pacific adults over four weeks. Twenty untrained (13 female) Pacific adults were randomised to intervention or control. Intervention participants were offered 45 minutes of small-sided games three times per week for four weeks. Control participants were offered one-month gym membership after the trial. Primary outcomes included cardiorespiratory fitness (VO₂peak) and leg strength (maximal concentric force of quadriceps at 60°/second) measured at baseline and four weeks. Secondary outcomes included glycaemia, lipid profile, blood pressure (BP), and inflammatory markers. Multivariable regression models were used to assess differences between groups, adjusting for baseline values, age and gender. At baseline, mean age was 34.8 years (SD 12.6), BMI 36.3 (6.7), systolic BP 127.7 mmHg (12.1), HbA1c 6.1% (1.9), VO₂peak 2.5 L/min (0.6) and leg strength 170.0 N.m (57.4). Sixteen participants completed the trial. Change in outcomes were greater in intervention than control participants in absolute VO₂peak (0.9 L/min (p=0.003)), leg strength (17.8 N.m (p=0.04)) and HDL (0.12 mmol/L (p=0.02)). There were no other significant differences. Small-sided games appear to be a promising means for improving the health and cardiorespiratory fitness and reducing the risk of diabetes and cardiovascular disease in Pacific adults.

Model based systems engineering (MBSE) applied to Radio Aurora Explorer (RAX) CubeSat mission operational scenarios

NASA Astrophysics Data System (ADS)

Spangelo, S. C.; Cutler, J.; Anderson, L.; Fosse, E.; Cheng, L.; Yntema, R.; Bajaj, M.; Delp, C.; Cole, B.; Soremekum, G.; Kaslow, D.

Small satellites are more highly resource-constrained by mass, power, volume, delivery timelines, and financial cost relative to their larger counterparts. Small satellites are operationally challenging because subsystem functions are coupled and constrained by the limited available commodities (e.g. data, energy, and access times to ground resources). Furthermore, additional operational complexities arise because small satellite components are physically integrated, which may yield thermal or radio frequency interference. In this paper, we extend our initial Model Based Systems Engineering (MBSE) framework developed for a small satellite mission by demonstrating the ability to model different behaviors and scenarios. We integrate several simulation tools to execute SysML-based behavior models, including subsystem functions and internal states of the spacecraft. We demonstrate utility of this approach to drive the system analysis and design process. We demonstrate applicability of the simulation environment to capture realistic satellite operational scenarios, which include energy collection, the data acquisition, and downloading to ground stations. The integrated modeling environment enables users to extract feasibility, performance, and robustness metrics. This enables visualization of both the physical states (e.g. position, attitude) and functional states (e.g. operating points of various subsystems) of the satellite for representative mission scenarios. The modeling approach presented in this paper offers satellite designers and operators the opportunity to assess the feasibility of vehicle and network parameters, as well as the feasibility of operational schedules. This will enable future missions to benefit from using these models throughout the full design, test, and fly cycle. In particular, vehicle and network parameters and schedules can be verified prior to being implemented, during mission operations, and can also be updated in near real-time with oper- tional performance feedback.

Training Undergraduate Physics Peer Tutors

NASA Astrophysics Data System (ADS)

Nossal, S. M.; Jacob, A. T.

2004-05-01

The University of Wisconsin's Physics Peer Mentor Tutor Program matches upper level undergraduate physics students in small study groups with students studying introductory algebra-based physics. We work with students who are potentially at-risk for having academic trouble with the course. They include students with a low exam score, learning disabilities, no high school physics, weak math backgrounds, and/or on academic probation. We also work with students from groups under represented in the sciences and who may be feeling isolated or marginal on campus such as minority, returning adult, and international students. The tutors provide a supportive learning environment, extra practice problems, and an overview of key concepts. In so doing, they help our students to build confidence and problem solving skills applicable to physics and other areas of their academic careers. The Physics Peer Mentor Tutor Program is modeled after a similar program for chemistry created by the University of Wisconsin's Chemistry Learning Center. Both programs are now run in collaboration. The tutors are chosen for their academic strength and excellent communication skills. Our tutors are majoring in physics, math, and secondary-level science education. The tutors receive ongoing training and supervision throughout the year. They attend weekly discipline-specific meetings to discuss strategies for teaching the content currently being discussed in the physics course. They also participate in a weekly teaching seminar with science tutors from chemistry and biochemistry to discuss teaching methods, mentoring, and general information relating to the students with whom we work. We will describe an overview of the Physics Peer Mentor Tutor Program with a focus on the teacher training program for our undergraduate tutors.

2015 Final Reports from the Los Alamos National Laboratory Computational Physics Student Summer Workshop

DOE Office of Scientific and Technical Information (OSTI.GOV)

Runnels, Scott Robert; Caldwell, Wendy; Brown, Barton Jed

The two primary purposes of LANL’s Computational Physics Student Summer Workshop are (1) To educate graduate and exceptional undergraduate students in the challenges and applications of computational physics of interest to LANL, and (2) Entice their interest toward those challenges. Computational physics is emerging as a discipline in its own right, combining expertise in mathematics, physics, and computer science. The mathematical aspects focus on numerical methods for solving equations on the computer as well as developing test problems with analytical solutions. The physics aspects are very broad, ranging from low-temperature material modeling to extremely high temperature plasma physics, radiation transportmore » and neutron transport. The computer science issues are concerned with matching numerical algorithms to emerging architectures and maintaining the quality of extremely large codes built to perform multi-physics calculations. Although graduate programs associated with computational physics are emerging, it is apparent that the pool of U.S. citizens in this multi-disciplinary field is relatively small and is typically not focused on the aspects that are of primary interest to LANL. Furthermore, more structured foundations for LANL interaction with universities in computational physics is needed; historically interactions rely heavily on individuals’ personalities and personal contacts. Thus a tertiary purpose of the Summer Workshop is to build an educational network of LANL researchers, university professors, and emerging students to advance the field and LANL’s involvement in it. This report includes both the background for the program and the reports from the students.« less

Reflective Optics Design for an LED High Beam Headlamp of Motorbikes

PubMed Central

Ge, Peng; Wang, Xiang; Li, Yang; Wang, Hong

2015-01-01

We propose a reflective optics design for an LED motorbike high beam lamp. We set the measuring screen as an elliptical zone and divide it into many small lattices and divide the spatial angle of the LED source into many parts and make relationships between them. According to the conservation law of energy and the Snell's law, the reflector is generated by freeform optics design method. Then the optical system is simulated by Monte Carlo method using ASAP software. Light pattern of simulation could meet the standard. The high beam headlamp is finally fabricated and assembled into a physical object. Experiment results can fully comply with United Nations Economic Commission for Europe (ECE) vehicle regulations R113 revision 2 (Class C). PMID:25961073

Radiometric observations of the 752.033-GHz rotational absorption line of H2O from a laboratory jet. [simulation of rocket plumes

NASA Technical Reports Server (NTRS)

Dionne, G. F.; Fitzgerald, J. F.; Chang, T.-S.; Fetterman, H. R.; Litvak, M. M.

1980-01-01

With the aid of a high-resolution two-stage heterodyne radiometer, spectral absorption measurements of the 752.033 GHz line of water vapor were carried out, using a blackbody continuum as a background radiation source for investigating the absorptive properties of the H2O content of high altitude rocket plumes. To simulate this physical situation in a laboratory environment, a small steam jet was operated within a large high-vacuum chamber, with the H2O jet plume traversing the radiometer line of sight. The experiments verified that this rotational line is optically thick, with excitation temperatures below 100 K, in the downstream part of the plume, as predicted by theoretical modelling.

High energy from space

NASA Technical Reports Server (NTRS)

Margon, Bruce; Canizares, Claude; Catura, Richard C.; Clark, George W.; Fichtel, Carl E.; Friedman, Herbert; Giacconi, Riccardo; Grindlay, Jonathan E.; Helfand, David J.; Holt, Stephen S.

1991-01-01

The following subject areas are covered: (1) important scientific problems for high energy astrophysics (stellar activity, the interstellar medium in galaxies, supernovae and endpoints of stellar evolution, nucleosynthesis, relativistic plasmas and matter under extreme conditions, nature of gamma-bursts, identification of black holes, active nuclei, accretion physics, large-scale structures, intracluster medium, nature of dark matter, and the X- and gamma-ray background); (2) the existing experimental programs (Advanced X-Ray Astrophysics Facility (AXAF), Gamma Ray Observatory (GRO), X-Ray Timing Explorer (XTE), High Energy Transient Experiment (HETE), U.S. participation in foreign missions, and attached Shuttle and Space Station Freedom payloads); (3) major missions for the 1990's; (4) a new program of moderate missions; (5) new opportunities for small missions; (6) technology development issues; and (7) policy issues.

Reflective optics design for an LED high beam headlamp of motorbikes.

PubMed

Ge, Peng; Wang, Xiang; Li, Yang; Wang, Hong

2015-01-01

We propose a reflective optics design for an LED motorbike high beam lamp. We set the measuring screen as an elliptical zone and divide it into many small lattices and divide the spatial angle of the LED source into many parts and make relationships between them. According to the conservation law of energy and the Snell's law, the reflector is generated by freeform optics design method. Then the optical system is simulated by Monte Carlo method using ASAP software. Light pattern of simulation could meet the standard. The high beam headlamp is finally fabricated and assembled into a physical object. Experiment results can fully comply with United Nations Economic Commission for Europe (ECE) vehicle regulations R113 revision 2 (Class C).

The influence of facility design and human resource management on health care professionals.

PubMed

Sadatsafavi, Hessam; Walewski, John; Shepley, Mardelle M

2015-01-01

Cost control of health care services is a strategic concern for organizations. To lower costs, some organizations reduce staffing levels. However, this may not be worth the trade-off, as the quality of services will likely be reduced, morale among health care providers tends to suffer, and patient satisfaction is likely to decline. The potential synergy between human resource management and facility design and operation was investigated to achieve the goal of providing cost containment strategies without sacrificing the quality of services and the commitment of employees. About 700 health care professionals from 10 acute-care hospitals participated in this cross-sectional study. The authors used structural equation modeling to test whether employees' evaluations of their physical work environment and human resource practices were significantly associated with lower job-related anxiety, higher job satisfaction, and higher organizational commitment. The analysis found that employees' evaluations of their physical work environment and human resource practices influenced their job-related feelings and attitudes. Perceived organizational support mediated this relationship. The study also found a small but positive interaction effect between the physical work environment and human resource practices. The influence of physical work environment was small, mainly because of the high predictive value of human resource practices and strong confounding variables included in the analysis. This study specifically showed the role of facility design in reducing job-related anxiety among caregivers. Preliminary evidence is provided that facility design can be used as a managerial tool for improving job-related attitudes and feelings of employees and earning their commitment. Providing a healthy and safe work environment can be perceived by employees as an indication that the organization respects them and cares about their well-being, which might be reciprocated with higher levels of motivation and commitment toward the organization.

Small rocket research and technology

NASA Technical Reports Server (NTRS)

Schneider, Steven; Biaglow, James

1993-01-01

Small chemical rockets are used on nearly all space missions. The small rocket program provides propulsion technology for civil and government space systems. Small rocket concepts are developed for systems which encompass reaction control for launch and orbit transfer systems, as well as on-board propulsion for large space systems and earth orbit and planetary spacecraft. Major roles for on-board propulsion include apogee kick, delta-V, de-orbit, drag makeup, final insertions, north-south stationkeeping, orbit change/trim, perigee kick, and reboost. The program encompasses efforts on earth-storable, space storable, and cryogenic propellants. The earth-storable propellants include nitrogen tetroxide (NTO) as an oxidizer with monomethylhydrazine (MMH) or anhydrous hydrazine (AH) as fuels. The space storable propellants include liquid oxygen (LOX) as an oxidizer with hydrazine or hydrocarbons such as liquid methane, ethane, and ethanol as fuels. Cryogenic propellants are LOX or gaseous oxygen (GOX) as oxidizers and liquid or gaseous hydrogen as fuels. Improved performance and lifetime for small chemical rockets are sought through the development of new predictive tools to understand the combustion and flow physics, the introduction of high temperature materials to eliminate fuel film cooling and its associated combustion inefficiency, and improved component designs to optimize performance. Improved predictive technology is sought through the comparison of both local and global predictions with experimental data. Results indicate that modeling of the injector and combustion process in small rockets needs improvement. High temperature materials require the development of fabrication processes, a durability data base in both laboratory and rocket environments, and basic engineering property data such as strength, creep, fatigue, and work hardening properties at both room and elevated temperature. Promising materials under development include iridium-coated rhenium and a ceramic composite of mixed hafnium carbide and tantalum carbide reinforced with graphite fibers.

Low temperature physical properties of Co-35Ni-20Cr-10Mo alloy MP35N®

NASA Astrophysics Data System (ADS)

Lu, J.; Toplosky, V. J.; Goddard, R. E.; Han, K.

2017-09-01

Multiphase Co-35Ni-20Cr-10Mo alloy MP35N® is a high strength alloy with excellent corrosion resistance. Its applications span chemical, medical, and food processing industries. Thanks to its high modulus and high strength, it found applications in reinforcement of ultra-high field pulsed magnets. Recently, it has also been considered for reinforcement in superconducting wires used in ultra-high field superconducting magnets. For these applications, accurate measurement of its physical properties at cryogenic temperatures is very important. In this paper, physical properties including electrical resistivity, specific heat, thermal conductivity, and magnetization of as-received and aged samples are measured from 2 to 300 K. The electrical resistivity of the aged sample is slightly higher than the as-received sample, both showing a weak linear temperature dependence in the entire range of 2-300 K. The measured specific heat Cp of 430 J/kg-K at 295 K agrees with a theoretical prediction, but is significantly smaller than the values in the literature. The thermal conductivity between 2 and 300 K is in good agreement with the literature which is only available above 77 K. Magnetic property of MP35N® changes significantly with aging. The as-received sample exhibits Curie paramagnetism with a Curie constant C = 0.175 K. While the aged sample contains small amounts of a ferromagnetic phase even at room temperature. The measured MP35N® properties will be useful for the engineering design of pulsed magnets and superconducting magnets using MP35N® as reinforcement.

Dense chitosan surgical membranes produced by a coincident compression-dehydration process

PubMed Central

Dooley, Thomas P.; Ellis, April L.; Belousova, Maria; Petersen, Don; DeCarlo, Arthur A.

2012-01-01

High density chitosan membranes were produced via a novel manufacturing process for use as implantable resorbable surgical membranes. The innovative method utilizes the following three sequential steps: (1) casting an acidic chitosan solution within a silicon mold, followed by freezing; (2) neutralizing the frozen acidic chitosan solution in alkaline solution to facilitate polymerization; and (3) applying coincident compression-dehydration under a vacuum. Resulting membranes of 0.2 – 0.5 mm thickness have densities as high as 1.6 g/cm3. Inclusion of glycerol prior to the compression-dehydration step provides additional physical and clinical handling benefits. The biomaterials exhibit tensile strength with a maximum load as high as 10.9 N at ~ 2.5 mm width and clinically-relevant resistance to suture pull-out with a maximum load as high as 2.2 N. These physical properties were superior to those of a commercial reconstituted collagen membrane. The dense chitosan membranes have excellent clinical handling characteristics, such as pliability and “memory” when wet. They are semi-permeable to small molecules, biodegradable in vitro in lysozyme solution, and the rates of degradation are inversely correlated to the degree of deacetylation. Furthermore, the dense chitosan membranes are biocompatible and resorbable in vivo as demonstrated in a rat oral wound healing model. The unique combination of physical, in vitro, in vivo, and clinical handling properties demonstrate the high utility of dense chitosan membranes produced by this new method. The materials may be useful as surgical barrier membranes, scaffolds for tissue engineering, wound dressings, and as delivery devices for active ingredients. PMID:23565872

Solving a Higgs optimization problem with quantum annealing for machine learning.

PubMed

Mott, Alex; Job, Joshua; Vlimant, Jean-Roch; Lidar, Daniel; Spiropulu, Maria

2017-10-18

The discovery of Higgs-boson decays in a background of standard-model processes was assisted by machine learning methods. The classifiers used to separate signals such as these from background are trained using highly unerring but not completely perfect simulations of the physical processes involved, often resulting in incorrect labelling of background processes or signals (label noise) and systematic errors. Here we use quantum and classical annealing (probabilistic techniques for approximating the global maximum or minimum of a given function) to solve a Higgs-signal-versus-background machine learning optimization problem, mapped to a problem of finding the ground state of a corresponding Ising spin model. We build a set of weak classifiers based on the kinematic observables of the Higgs decay photons, which we then use to construct a strong classifier. This strong classifier is highly resilient against overtraining and against errors in the correlations of the physical observables in the training data. We show that the resulting quantum and classical annealing-based classifier systems perform comparably to the state-of-the-art machine learning methods that are currently used in particle physics. However, in contrast to these methods, the annealing-based classifiers are simple functions of directly interpretable experimental parameters with clear physical meaning. The annealer-trained classifiers use the excited states in the vicinity of the ground state and demonstrate some advantage over traditional machine learning methods for small training datasets. Given the relative simplicity of the algorithm and its robustness to error, this technique may find application in other areas of experimental particle physics, such as real-time decision making in event-selection problems and classification in neutrino physics.