Physical aging in pharmaceutical polymers and the effect on solid oral dosage form stability.

PubMed

Kucera, Shawn A; Felton, Linda A; McGinity, James W

2013-12-05

The application of a polymeric film to a solid oral dosage form can be an effective technique to modify drug release. Most polymers used for such purposes are amorphous in nature and are subject to physical aging. This physical aging phenomenon has been shown to cause changes not only in the mechanical and drug release properties of polymeric films, but also the permeability of these films due to a densification and decrease in free volume of the polymer as the material relaxes to an equilibrated thermodynamic state. Temperature, humidity, and additional excipients in the coating formulations have been shown to influence the aging process. This review article discusses the process of physical aging in films prepared from aqueous dispersions, describes various analytical techniques that can be used to investigate the aging process, and highlights strategies to prevent such aging. Copyright © 2013 Elsevier B.V. All rights reserved.

Space Biophysics: Accomplishments, Trends, Challenges

NASA Technical Reports Server (NTRS)

Smith, Jeffrey D.

2015-01-01

Physics and biology are inextricably linked. All the chemical and biological processes of life are dutifully bound to follow the rules and laws of physics. In space, these physical laws seem to turn on their head and biological systems, from microbes to humans, adapt and evolve in myriad ways to cope with the changed physical influences of the space environment. Gravity is the most prominent change in space that influences biology. In microgravity, the physical processes of sedimentation, density-driven convective flow, influence of surface tension and fluid pressure profoundly influence biology at the molecular and cellular level as well as at the whole-body level. Gravity sensing mechanisms are altered, structural and functional components of biology (such as bone and muscle) are reduced and changes in the way fluids and gasses behave also drive the way microbial systems and biofilms grow as well as the way plants and animals adapt. The radiation environment also effects life in space. Solar particle events and high energy cosmic radiation can cause serious damage to DNA and other biomolecules. The results can cause mutation, cellular damage or death, leading to health consequences of acute radiation damage or long-term health consequences such as increased cancer risk. Space Biophysics is the study and utilization of physical changes in space that cause changes in biological systems. The unique physical environment in space has been used successfully to grow high-quality protein crystals and 3D tissue cultures that could not be grown in the presence of unidirectional gravitational acceleration here on Earth. All biological processes that change in space have their root in a biophysical alteration due to microgravity and/or the radiation environment of space. In order to fully-understand the risks to human health in space and to fully-understand how humans, plants, animals and microbes can safely and effectively travel and eventually live for long periods beyond the protective environment of Earth, the biophysical properties underlying these changes must be studied, characterized and understood. This lecture reviews the current state of NASA biophysics research accomplishments and identifies future trends and challenges for biophysics research on the International Space Station and beyond.

The Relationship of Health and Nutrition to the Learning Process.

ERIC Educational Resources Information Center

Norwood, Glenda R.

In addition to identifying the causes and physical effects of various nutritional deficiencies, this discussion describes the effects of each deficiency on the learning process. The recommended daily food intake for children and teenagers is also noted. Eight types of nutritional deficiency are discussed in detail: (1) malnutrition (both…

EXAMINATION OF THE PATELLOFEMORAL JOINT

PubMed Central

Davies, George J.

2016-01-01

Patellofemoral pain is one of the leading causes of knee pain in athletes. The many causes of patellofemoral pain make diagnosis unpredictable and examination and treatment difficult. This clinical commentary discusses a detailed physical examination routine for the patient with patellofemoral pain. Critically listening and obtaining a detailed medical history followed by a clearly structured physical examination will allow the physical therapist to diagnose most forms of patellofemoral pain. This clinical commentary goes one step further by suggesting an examination scheme and order in which it should be performed during the examination process. This step-by-step guide will be helpful for the student or novice therapist and serve as review for those that are already well versed in patellofemoral examination. PMID:27904788

Effects of agriculture on wood breakdown and microbial biofilm respiration in southern Appalachian streams

Treesearch

M.E. McTammany; E.F. Benfield; J.R. Webster

2008-01-01

Agriculture causes high sediment, nutrient and light input to streams, which may affect rates of ecosystem processes, such as organic matter decay. In the southern Appalachians, socioeconomic trends over the past 50 years have caused widespread abandonment of farmland with subsequent reforestation. Physical and chemical properties of streams in these...

Effects of agriculture on wood breakdown and microbial biofilm respiration in southern Appalachian streams

Treesearch

E.F Benfield McTammany; J.R. Webster

2008-01-01

Agriculture causes high sediment, nutrient and light input to streams, which may affect rates of ecosystem processes, such as organic matter decay. In the southern Appalachians, socioeconomic trends over the past 50 years have caused widespread abandonment of farmland with subsequent reforestation. Physical and chemical properties of streams in these reforested areas...

Puberty

MedlinePlus

Puberty is the time in life when a boy or girl becomes sexually mature. It is a process that ... for boys. It causes physical changes, and affects boys and girls differently. In girls: The first sign of puberty ...

Effect of pressure on rate of burning /decomposition with flame/ of liquid hydrazine.

NASA Technical Reports Server (NTRS)

Antoine, A. C.

1966-01-01

Liquid hydrazine decomposition process to determine what chemical or physical changes may be occurring that cause breaks in burning rate/ pressure curves, measuring flame temperature and light emission

Modifications to population rate equations resulting from correlations between collisional and radiative processes

NASA Technical Reports Server (NTRS)

Ballagh, R. J.; Cooper, J.

1984-01-01

There are many systems of physical interest for which a set of rate equations for level populations can provide insight. If the system has two (or more) different mechanisms for effecting transition between levels, total rates of transfer are usually taken as the sum of rates that the individual mechanisms would cause acting alone. Using the example of a hydrogen atom subjected to (ionic and electronic) collisions and external radiation, it is shown that when these individual mechanisms overlap, the total transfer rates must be modified to account for correlations between collisional and radiative processes. For a broad-band radiation field the modified rates have a simple physical interpretation. In the case of a narrow-band field the overlapping events may cause new coherences to appear and interpretation of the modified 'rates' is more complicated.

Radiation Belt Storm Probes: Resolving Fundamental Physics with Practical Consequences

NASA Technical Reports Server (NTRS)

Ukhorskiy, Aleksandr Y.; Mauk, Barry H.; Fox, Nicola J.; Sibeck, David G.; Grebowsky, Joseph M.

2011-01-01

The fundamental processes that energize, transport, and cause the loss of charged particles operate throughout the universe at locations as diverse as magnetized planets, the solar wind, our Sun, and other stars. The same processes operate within our immediate environment, the Earth's radiation belts. The Radiation Belt Storm Probes (RBSP) mission will provide coordinated two-spacecraft observations to obtain understanding of these fundamental processes controlling the dynamic variability of the near-Earth radiation environment. In this paper we discuss some of the profound mysteries of the radiation belt physics that will be addressed by RBSP and briefly describe the mission and its goals.

Foundations of anticipatory logic in biology and physics.

PubMed

Bettinger, Jesse S; Eastman, Timothy E

2017-12-01

Recent advances in modern physics and biology reveal several scenarios in which top-down effects (Ellis, 2016) and anticipatory systems (Rosen, 1980) indicate processes at work enabling active modeling and inference such that anticipated effects project onto potential causes. We extrapolate a broad landscape of anticipatory systems in the natural sciences extending to computational neuroscience of perception in the capacity of Bayesian inferential models of predictive processing. This line of reasoning also comes with philosophical foundations, which we develop in terms of counterfactual reasoning and possibility space, Whitehead's process thought, and correlations with Eastern wisdom traditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Watershed rehabilitation: a process view

Treesearch

Robert R. Ziemer

1981-01-01

Abstract - The most effective control of erosion, in both physical and economic terms, is through prevention because once natural erosion is accelerated, corrective action is not only expensive but seldom entirely successful. To control erosion it is important to understand the forces that cause material to move or resist movement. Once the forces and processes of...

Modelling accumulation of marine plastics in the coastal zone; what are the dominant physical processes?

NASA Astrophysics Data System (ADS)

Critchell, Kay; Lambrechts, Jonathan

2016-03-01

Anthropogenic marine debris, mainly of plastic origin, is accumulating in estuarine and coastal environments around the world causing damage to fauna, flora and habitats. Plastics also have the potential to accumulate in the food web, as well as causing economic losses to tourism and sea-going industries. If we are to manage this increasing threat, we must first understand where debris is accumulating and why these locations are different to others that do not accumulate large amounts of marine debris. This paper demonstrates an advection-diffusion model that includes beaching, settling, resuspension/re-floating, degradation and topographic effects on the wind in nearshore waters to quantify the relative importance of these physical processes governing plastic debris accumulation. The aim of this paper is to prioritise research that will improve modelling outputs in the future. We have found that the physical characteristic of the source location has by far the largest effect on the fate of the debris. The diffusivity, used to parameterise the sub-grid scale movements, and the relationship between debris resuspension/re-floating from beaches and the wind shadow created by high islands also has a dramatic impact on the modelling results. The rate of degradation of macroplastics into microplastics also have a large influence in the result of the modelling. The other processes presented (settling, wind drift velocity) also help determine the fate of debris, but to a lesser degree. These findings may help prioritise research on physical processes that affect plastic accumulation, leading to more accurate modelling, and subsequently management in the future.

Assessment of working conditions in a modern Russian milk processing plant from the aspect of occupational medicine.

PubMed

Belova, L V; Mishkich, I A; Kresova, G A; Liubomudrova, T A

1999-03-01

Assessment of harmful industrial factors caused by work conditions in a modern milk processing plant. Work conditions, rest, nutrition, medical service, and subjective health indices among the employees in a new milk processing plant were studied. We used a specially formed questionnaire; instrumental measurements of microclimate parameters, noise, and illumination at workplace; laboratory physical and chemical evaluation of air pollution with aerosols and gases in the plant premises; chronometric studies determining the workers' activity during the working day location, and physical and psychological body exertion at the time of industrial activities; and assessment of design and operating documents of the plant. Laboratory studies included 157 workers, 1,724 tests, 26 chronometric studies, and analysis of 11 plant's documents. Unfavorable microclimatic conditions, noise, inadequate illumination, air pollution with dust and toxic substances, physical workload, increased demand for concentration, and monotony of labor in mass production professions were found. A great proportion of workers was dissatisfied with their working conditions and many suffered from occupational diseases and work-related diseases. The conditions of work in the studied milk processing plant may be classified as harmful and dangerous. The flaws in technological process, omissions in design and construction of the plant, as well as its improper exploitation aggravated industrial harmful factors. In combination with unsatisfactory organization of rest, nutrition, and medical services in the plant these factors may affect the workers' health and cause general and occupational diseases.

Planning Model of Physics Learning In Senior High School To Develop Problem Solving Creativity Based On National Standard Of Education

NASA Astrophysics Data System (ADS)

Putra, A.; Masril, M.; Yurnetti, Y.

2018-04-01

One of the causes of low achievement of student’s competence in physics learning in high school is the process which they have not been able to develop student’s creativity in problem solving. This is shown that the teacher’s learning plan is not accordance with the National Eduction Standard. This study aims to produce a reconstruction model of physics learning that fullfil the competency standards, content standards, and assessment standards in accordance with applicable curriculum standards. The development process follows: Needs analysis, product design, product development, implementation, and product evaluation. The research process involves 2 peers judgment, 4 experts judgment and two study groups of high school students in Padang. The data obtained, in the form of qualitative and quantitative data that collected through documentation, observation, questionnaires, and tests. The result of this research up to the product development stage that obtained the physics learning plan model that meets the validity of the content and the validity of the construction in terms of the fulfillment of Basic Competence, Content Standards, Process Standards and Assessment Standards.

Color Changes Mark Polymer Reactions.

ERIC Educational Resources Information Center

Krieger, James H.

1980-01-01

Describes how polydiacetylenes can be used as educational aids. These polymers have conjugated backbones, which cause changes in color when the polydiacetylenes undergo various chemical and physical processes. Diagrams summarize all chemical reactions and their associated color changes. (CS)

Clinical Manifestations and Overall Management Strategies for Duchenne Muscular Dystrophy.

PubMed

Tsuda, Takeshi

2018-01-01

Duchenne muscular dystrophy (DMD) is an X-linked genetic disorder that causes progressive weakness and wasting of skeletal muscular and myocardium in boys due to mutation of dystrophin. The structural integrity of each individual skeletal and cardiac myocyte is significantly compromised upon physical stress due to the absence of dystrophin. The progressive destruction of systemic musculature and myocardium causes affected patients to develop multiple organ disabilities, including loss of ambulation, physical immobility, neuromuscular scoliosis, joint contracture, restrictive lung disease, obstructive sleep apnea, and cardiomyopathy. There are some central nervous system-related medical problems, as dystrophin is also expressed in the neuronal tissues. Although principal management is to mainly delay the pathological process, an enhanced understanding of underlying pathological processes has significantly improved quality of life and longevity for DMD patients. Future research in novel molecular approach is warranted to answer unanswered questions.

Downdraft outflows: climatological potential to influence fire behaviour

Treesearch

Brian E. Potter; Jaime R. Hernandez

2017-01-01

Sudden wind shifts caused by atmospheric gust fronts can lead to firefighter entrapments and fatalities. In this study, we describe the physical processes involved in the related phenomena of convective downdrafts, gust fronts and downbursts. We focus on the dominant process, evaporative cooling in a dry surface layer, as characterised by the measure known as downdraft...

Formulation and process considerations affecting the stability of solid dosage forms formulated with methacrylate copolymers.

PubMed

Petereit, H U; Weisbrod, W

1999-01-01

General considerations concerning the stability of coated dosage forms are discussed, in order to avoid predictable interactions which may cause long-term stability problems. As polymers themselves maintain a high chemical stability and a low reactivity, instability phenomena mainly have to be explained by interactions of low molecular weight substances or physical changes. Possible interactions of functional groups can be predicted easily and insulating subcoates are proper countermeasures. Impurities, remaining in the polymeric material from the manufacturing process, may accelerate the hydrolysis of sensitive drugs. Instabilities of coated dosage forms are mainly based on physical interactions, caused by improper formulations of coating suspensions (i.e. plasticizers or pigments) or the film coating process. Residual moisture or solvents, probably enclosed in the core and migrating over time, may increase the permeability of coatings, due to plasticizing effects. The functionality of coatings from aqueous dispersions is linked to coalescence of latex particles. Thus any incomplete film formation, caused by too high or too low coating temperatures, may result in high permeable coatings. During storage, preferably under stress conditions this process will continue and thus change the release profile. Therefore bed temperatures of 10-20 degrees C above MFT must ensure the formation of homogeneous polymer layers during the coating process. Stability test procedures and packaging materials also need to be adapted to the physicochemical properties of the dosage form, in order to get meaningful results in stability tests.

Physics of Forced Unsteady Separation

NASA Technical Reports Server (NTRS)

Carr, Lawrence W. (Editor)

1992-01-01

This report contains the proceedings of a workshop held at NASA Ames Research Center in April 1990. This workshop was jointly organized by NASA, the Air Force Office of Scientific Research (AFOSR), and the Army Research Office (ARO), and was directed toward improved understanding of the physical processes that cause unsteady separation to occur. The proceedings contain the written contributions for the workshop, and include selected viewgraphs used in the various presentations.

The expansion of a plasma into a vacuum - Basic phenomena and processes and applications to space plasma physics

NASA Technical Reports Server (NTRS)

Wright, K. H., Jr.; Stone, N. H.; Samir, U.

1983-01-01

In this review attention is called to basic phenomena and physical processes involved in the expansion of a plasma into a vacuum, or the expansion of a plasma into a more tenuous plasma, in particular the fact that upon the expansion, ions are accelerated and reach energies well above their thermal energy. Also, in the process of the expansion a rarefaction wave propagates into the ambient plasma, an ion front moves into the expansion volume, and discontinuities in plasma parameters occur. The physical processes which cause the above phenomena are discussed, and their possible application is suggested for the case of the distribution of ions and electrons (hence plasma potential and electric fields) in the wake region behind artificial and natural obstacles moving supersonically in a rarefied space plasma. To illustrate this, some in situ results are reexamined. Directions for future work in this area via the utilization of the Space Shuttle and laboratory work are also mentioned.

Physical aging in comets

NASA Technical Reports Server (NTRS)

Meech, Karen J.

1991-01-01

The question of physical aging in cometary nuclei is addressed in order to elucidate the relationship between the past conditions in the protosolar nebula and the present state of the cometary nucleus, and to understand the processes that will physically and chemically alter the nucleus as a function of time. Attention is given to some of the processes that might be responsible for causing aging in comets, namely, radiation damage in the upper layers of the nucleus during the long residences in the Oort cloud, processing from heating and collisions within the Oort cloud, loss of highly volatile species from the nucleus on the first passage through the inner solar system, buildup of a dusty mantle, which can eventually prohibit further sublimation, and a change in the porosity, and hence the thermal properties, of the nucleus. Recent observations suggest that there are distinct differences between 'fresh' Oort cloud comets and thermally processed periodic comets with respect to intrinsic brightness and rate of change of activity as a function of distance.

The symbolic power of money: reminders of money alter social distress and physical pain.

PubMed

Zhou, Xinyue; Vohs, Kathleen D; Baumeister, Roy F

2009-06-01

People often get what they want from the social system, and that process is aided by social popularity or by having money. Money can thus possibly substitute for social acceptance in conferring the ability to obtain benefits from the social system. Moreover, past work has suggested that responses to physical pain and social distress share common underlying mechanisms. Six studies tested relationships among reminders of money, social exclusion, and physical pain. Interpersonal rejection and physical pain caused desire for money to increase. Handling money (compared with handling paper) reduced distress over social exclusion and diminished the physical pain of immersion in hot water. Being reminded of having spent money, however, intensified both social distress and physical pain.

Processes and Instructions Encouraging Thai Students Consistently Pass the First Round of The National Physics Academics Olympiads

NASA Astrophysics Data System (ADS)

Teevasuthornsakul, Chalongchai; Manosuttirit, Artnarong; Suwanno, Chirasak; Sutsaguan, Lanchakorn

2010-07-01

This research focused on the processes and physics instruction of 25 schools located in Bangkok and up-country in Thailand in order to explain why many of their students have passed the first round of the National Physics Academic Olympiads consistently. The high schools in Thailand can apply and support their students and develop their potential in physics. The development of physics professional is the cornerstone of a developing country and increase physics quality base on sciences development in the future in Thailand. The duration of collecting all data was from May 2007 to May 2009. The methodology for this research was the qualitative research method. The researchers interviewed managers, teachers and students at each school location or used semi-structured interview forms. The researchers used the Investigator Triangulation approach to check the qualitative data and the Cause and Effect Analysis approach to analyze situation factors. The results showed that in processes were include 1) enhanced the students with the Academic Olympiads to develop the capacities of students; 2) motivated the students with processes such as good instruction in physics and special privilege in continuing studies in university; and 3) tutorial systems and drill and practice systems support students into subsequent rounds. 4) Admiration activities accommodated the students continually and suitably. Most of the teaching styles used in their lectures, in both basic contents and practice, encouraged students to analyze entrance examination papers, little laboratory. While students say that" They just know that a physics laboratory is very important to study physics after they passed Olympic camp."

Being qua becoming: Aristotle's "Metaphysics", quantum physics, and Process Philosophy

NASA Astrophysics Data System (ADS)

Johnson, David Kelley

In Aristotle's First Philosophy, science and philosophy were partners, but with the rise of empiricism, went their separate ways. Metaphysics combined the rational and irrational (i.e. final cause/unmoved mover) elements of existence to equate being with substance, postulating prime matter as pure potential that was actuated by form to create everything. Modern science reveres pure reason and postulates its theory of being by a rigorous scientific methodology. The Standard Model defines matter as energy formed into fundamental particles via forces contained in fields. Science has proved Aristotle's universe wrong in many ways, but as physics delves deeper into the quantum world, empiricism is reaching its limits concerning fundamental questions of existence. To achieve its avowed mission of explaining existence completely, physics must reunite with philosophy in a metascience modeled on the First Philosophy of Aristotle. One theory of being that integrates quantum physics and metaphysics is Process Philosophy.

Tendons – time to revisit inflammation

PubMed Central

Rees, Jonathan D; Stride, Matthew; Scott, Alex

2014-01-01

It is currently widely accepted among clinicians that chronic tendinopathy is caused by a degenerative process devoid of inflammation. Current treatment strategies are focused on physical treatments, peritendinous or intratendinous injections of blood or blood products and interruption of painful stimuli. Results have been at best, moderately good and at worst a failure. The evidence for non-infammatory degenerative processes alone as the cause of tendinopathy is surprisingly weak. There is convincing evidence that the inflammatory response is a key component of chronic tendinopathy. Newer anti-inflammatory modalities may provide alternative potential opportunities in treating chronic tendinopathies and should be explored further. PMID:23476034

Cutaneous Scarring: A Clinical Review

PubMed Central

Baker, Richard; Urso-Baiarda, Fulvio; Linge, Claire; Grobbelaar, Adriaan

2009-01-01

Cutaneous scarring can cause patients symptoms ranging from the psychological to physical pain. Although the process of normal scarring is well described the ultimate cause of pathological scarring remains unknown. Similarly, exactly how early gestation fetuses can heal scarlessly remains unsolved. These questions are crucial in the search for a preventative or curative antiscarring agent. Such a discovery would be of enormous medical and commercial importance, not least because it may have application in other tissues. In the clinical context the assessment of scars is becoming more sophisticated and new physical, medical and surgical therapies are being introduced. This review aims to summarise some of the recent developments in scarring research for non-specialists and specialists alike. PMID:20585482

Uncertainties in s-process nucleosynthesis in massive stars determined by Monte Carlo variations

NASA Astrophysics Data System (ADS)

Nishimura, N.; Hirschi, R.; Rauscher, T.; St. J. Murphy, A.; Cescutti, G.

2017-08-01

The s-process in massive stars produces the weak component of the s-process (nuclei up to A ˜ 90), in amounts that match solar abundances. For heavier isotopes, such as barium, production through neutron capture is significantly enhanced in very metal-poor stars with fast rotation. However, detailed theoretical predictions for the resulting final s-process abundances have important uncertainties caused both by the underlying uncertainties in the nuclear physics (principally neutron-capture reaction and β-decay rates) as well as by the stellar evolution modelling. In this work, we investigated the impact of nuclear-physics uncertainties relevant to the s-process in massive stars. Using a Monte Carlo based approach, we performed extensive nuclear reaction network calculations that include newly evaluated upper and lower limits for the individual temperature-dependent reaction rates. We found that most of the uncertainty in the final abundances is caused by uncertainties in the neutron-capture rates, while β-decay rate uncertainties affect only a few nuclei near s-process branchings. The s-process in rotating metal-poor stars shows quantitatively different uncertainties and key reactions, although the qualitative characteristics are similar. We confirmed that our results do not significantly change at different metallicities for fast rotating massive stars in the very low metallicity regime. We highlight which of the identified key reactions are realistic candidates for improved measurement by future experiments.

Systemic lupus erythematosus presenting as morbid jealousy.

PubMed Central

Ravindran, A.; Carney, M. W.; Denman, A. M.

1980-01-01

A patient fulfilling the diagnostic criteria for systemic lupus erythematosus and presenting with morbid jealousy is described. There was evidence of cerebral lupus. Her physical and mental symptoms responded to a combination of chlorpromazine and steroids. The morbid mental process was probably caused by her physical condition while the content of her disordered thought and behaviour was determined by her introverted premorbid personality, religiosity, unhappy childhood experiences and frustrated desire for children. PMID:7413541

Inaccuracies in additive manufactured medical skull models caused by the DICOM to STL conversion process.

PubMed

Huotilainen, Eero; Jaanimets, Risto; Valášek, Jiří; Marcián, Petr; Salmi, Mika; Tuomi, Jukka; Mäkitie, Antti; Wolff, Jan

2014-07-01

The process of fabricating physical medical skull models requires many steps, each of which is a potential source of geometric error. The aim of this study was to demonstrate inaccuracies and differences caused by DICOM to STL conversion in additively manufactured medical skull models. Three different institutes were requested to perform an automatic reconstruction from an identical DICOM data set of a patients undergoing tumour surgery into an STL file format using their software of preference. The acquired digitized STL data sets were assessed and compared and subsequently used to fabricate physical medical skull models. The three fabricated skull models were then scanned, and differences in the model geometries were assessed using established CAD inspection software methods. A large variation was noted in size and anatomical geometries of the three physical skull models fabricated from an identical (or "a single") DICOM data set. A medical skull model of the same individual can vary markedly depending on the DICOM to STL conversion software and the technical parameters used. Clinicians should be aware of this inaccuracy in certain applications. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Sickness absence, marginality, and medically unexplained physical symptoms: a focus-group study of patients' experiences.

PubMed

Aamland, Aase; Werner, Erik L; Malterud, Kirsti

2013-06-01

Medically unexplained physical symptoms (MUPS) form a major cause of sickness absence. The purpose of this study was to explore factors which may influence further marginalization among patients with MUPS on long-term sickness absence. Two focus-group discussions were conducted with a purposive sample of 12 participants, six men and six women, aged 24-59 years. Their average duration of sickness absence was 10.5 months. Participants were invited to share stories about experiences from the process leading to the ongoing sickness absence, with a focus on the causes being medically unexplained. Systematic text condensation was applied for analysis. Inspired by theories of marginalization and coping, the authors searched for knowledge of how patients' positive resources can be mobilized to counteract processes of marginality. Analysis revealed how invisible symptoms and lack of objective findings were perceived as an additional burden to the sickness absence itself. Factors that could counteract further marginalization were a supportive social network, positive coping strategies such as keeping to the daily schedule and physical activity, and positive attention and confidence from professionals. Confidence from both personal and professional contacts is crucial. GPs have an important and appreciated role in this aspect.

Understanding earthquake from the granular physics point of view — Causes of earthquake, earthquake precursors and predictions

NASA Astrophysics Data System (ADS)

Lu, Kunquan; Hou, Meiying; Jiang, Zehui; Wang, Qiang; Sun, Gang; Liu, Jixing

2018-03-01

We treat the earth crust and mantle as large scale discrete matters based on the principles of granular physics and existing experimental observations. Main outcomes are: A granular model of the structure and movement of the earth crust and mantle is established. The formation mechanism of the tectonic forces, which causes the earthquake, and a model of propagation for precursory information are proposed. Properties of the seismic precursory information and its relevance with the earthquake occurrence are illustrated, and principle of ways to detect the effective seismic precursor is elaborated. The mechanism of deep-focus earthquake is also explained by the jamming-unjamming transition of the granular flow. Some earthquake phenomena which were previously difficult to understand are explained, and the predictability of the earthquake is discussed. Due to the discrete nature of the earth crust and mantle, the continuum theory no longer applies during the quasi-static seismological process. In this paper, based on the principles of granular physics, we study the causes of earthquakes, earthquake precursors and predictions, and a new understanding, different from the traditional seismological viewpoint, is obtained.

7 CFR 160.4 - Reclaimed rosin.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... contaminating component remaining from the waste material itself or from any article used in the recovery process is not sufficient to cause the physical or chemical properties of the reclaimed product to differ...

Postfact phenomena of the wet-steam flow electrization in turbines

NASA Astrophysics Data System (ADS)

Tarelin, A. A.

2017-11-01

Physical processes occurring in a turbine with natural electrization of a humidity-steam flow and their effect on efficiency and reliability of the turbine operation has been considered. Causes of the electrical potential occurrence on a rotor shaft are analyzed. The wet steam's electrization exposure on the electrical potential that is one of the major factors of bearings' electroerosion has been demonstrated on the full-scale installation. Hydrogen formation in wheelspace of the turbine as a result of electrochemical processes and electric field exposure of the space charge has been considered. Hydrogen concentration dependence on a volume charge density in the steam flow has been determined. It is stated that the processes occurring behind the final stage of wet-steam turbines are similar to the ones in elaerosol ectrostatic generators. It has been demonstrated that this phenomenon causes the flow's temporal inhibition and starts pulsations. These factors' impact on power loss of the turbine has been evaluated and recommendations for their elimination have been offered. It has been determined that motions of charged drops can cause self-maintained discharges inside of the flow and between the flow and grounded surfaces that are accompanied by electromagnetic radiation of the wide spectrum. The integrated studies have shown that physical phenomena occurring due to natural electrization negatively affect efficiency and reliability of the turbine operation. Practical recommendations allowing one to minimize the negative effects of the flow natural electrization process have been offered.

Physical and mathematical modeling of antimicrobial photodynamic therapy

NASA Astrophysics Data System (ADS)

Bürgermeister, Lisa; López, Fernando Romero; Schulz, Wolfgang

2014-07-01

Antimicrobial photodynamic therapy (aPDT) is a promising method to treat local bacterial infections. The therapy is painless and does not cause bacterial resistances. However, there are gaps in understanding the dynamics of the processes, especially in periodontal treatment. This work describes the advances in fundamental physical and mathematical modeling of aPDT used for interpretation of experimental evidence. The result is a two-dimensional model of aPDT in a dental pocket phantom model. In this model, the propagation of laser light and the kinetics of the chemical reactions are described as coupled processes. The laser light induces the chemical processes depending on its intensity. As a consequence of the chemical processes, the local optical properties and distribution of laser light change as well as the reaction rates. The mathematical description of these coupled processes will help to develop treatment protocols and is the first step toward an inline feedback system for aPDT users.

The influence of intuition and communication language in generating student conceptions

NASA Astrophysics Data System (ADS)

Handhika, J.; Cari, C.; Suparmi, A.; Sunarno, W.

2017-11-01

This research aims to describe the influence of intuition and communication language in generating student conceptions. The conception diagnostic test is used to reveal student conception. The diagnostic test results described and communication language profiled by giving instruction to students to make sentences using physics quantities. Sentences expressed by students are reduced and profiled potential effects. Obtained information that (1) Students generalize non-scientific experience (based on feeling) into the physics problem. This process caused misconception. Communication language can make the students difficult to understand the concept because of the difference meaning of communication and physics language.

Sick-listed employees with severe medically unexplained physical symptoms: burden or routine for the occupational health physician? A cross sectional study

PubMed Central

2010-01-01

Background The two primary objectives of this study were to the assess consultation load of occupational health physicians (OHPs), and their difficulties and needs with regard to their sickness certification tasks in sick-listed employees with severe medical unexplained physical symptoms (MUPS). Third objective was to determine which disease-, patient-, doctor- and practice-related factors are associated with the difficulties and needs of the OHPs. Methods In this cross-sectional study, 43 participating OHPs from 5 group practices assessed 489 sick-listed employees with and without severe MUPS. The OHPs filled in a questionnaire about difficulties concerning sickness certification tasks, consultation time, their needs with regard to consultation with or referral to a psychiatrist or psychologist, and communication with GPs. The OHPs also completed a questionnaire about their personal characteristics. Results OHPs only experienced task difficulties in employees with severe MUPS in relation to their communication with the treating physician. This only occured in cases in which the OHP attributed the physical symptoms to somatoform causes. If they attributed the physical symptoms to mental causes, the OHPs reported a need to consultate a psychiatrist about the diagnosis and treatment. Conclusions OHPs experience few difficulties with their sickness certification tasks and consultation load concerning employees with severe MUPS. However, they encounter problems if the diagnostic uncertainties of the treating physician interfere with the return to work process. OHPs have a need for psychiatric expertise whenever they are uncertain about the psychiatric causes of a delayed return to work process. We recommend further training programs for OHPs. They should also have more opportunity for consultation and referral to a psychiatrist, and their communication with treating physicians should be improved. PMID:21059232

Laboratory Investigation on Physical and Mechanical Properties of Granite After Heating and Water-Cooling Treatment

NASA Astrophysics Data System (ADS)

Zhang, Fan; Zhao, Jianjian; Hu, Dawei; Skoczylas, Frederic; Shao, Jianfu

2018-03-01

High-temperature treatment may cause changes in physical and mechanical properties of rocks. Temperature changing rate (heating, cooling and both of them) plays an important role in those changes. Thermal conductivity tests, ultrasonic pulse velocity tests, gas permeability tests and triaxial compression tests are performed on granite samples after a heating and rapid cooling treatment in order to characterize the changes in physical and mechanical properties. Seven levels of temperature (from 25 to 900 °C) are used. It is found that the physical and mechanical properties of granite are significantly deteriorated by the thermal treatment. The porosity shows a significant increase from 1.19% at the initial state to 6.13% for samples heated to 900 °C. The increase in porosity is mainly due to three factors: (1) a large number of microcracks caused by the rapid cooling rate; (2) the mineral transformation of granite through high-temperature heating and water-cooling process; (3) the rapid cooling process causes the mineral particles to weaken. As the temperature of treatment increases, the thermal conductivity and P-wave velocity decrease while the gas permeability increases. Below 200 °C, the elastic modulus and cohesion increase with temperature increasing. Between 200 and 500 °C, the elastic modulus and cohesion have no obvious change with temperature. Beyond 500 °C, as the temperature increases, the elastic modulus and cohesion obviously decrease and the decreasing rate becomes slower with the increase in confining pressure. Poisson's ratio and internal frictional coefficient have no obvious change as the temperature increases. Moreover, there is a transition from a brittle to ductile behavior when the temperature becomes high. At 900 °C, the granite shows an obvious elastic-plastic behavior.

Bridging Physics and Biology Using Resistance and Axons

NASA Astrophysics Data System (ADS)

Dyer, Joshua M.

2014-11-01

When teaching physics, it is often difficult to get biology-oriented students to see the relevance of physics.1 A complaint often heard is that biology students are required to take physics for the Medical College Admission Test (MCAT) as part of a "weeding out" process, but that they don't feel like they need physics for biology. Despite this impression held by students, there have been calls for better physics education for future physicians and life scientists.2,3 Research is being performed to improve physics classes and labs by linking topics in biology and physics.4,5 Described here is a laboratory experiment covering the topics of resistance of materials and circuits/Kirchhoff's laws in a biology context with their direct application to neurons, axons, and electrical impulse transmission within animals. This experiment will also demonstrate the mechanism believed to cause multiple sclerosis. The apparatus was designed with low-cost and readily available materials in mind.

Sex that moves mountains: The influence of spawning fish on river profiles over geologic timescales

NASA Astrophysics Data System (ADS)

Fremier, Alexander K.; Yanites, Brian J.; Yager, Elowyn M.

2018-03-01

A key component of resilience is to understand feedbacks among components of biophysical systems, such as physical drivers, ecological responses and the subsequent feedbacks onto physical process. While physically based explanations of biological speciation are common (e.g., mountains separating a species can lead to speciation), less common is the inverse process examined: can a speciation event have significant influence on physical processes and patterns in a landscape? When such processes are considered, such as with 'ecosystem engineers', many studies have focused on the short-term physical and biological effects rather than the long-term impacts. Here, we formalized the physical influence of salmon spawning on stream beds into a model of channel profile evolution by altering the critical shear stress required to move stream bed particles. We then asked if spawning and an adaptive radiation event (similar to the one that occurred in Pacific salmon species) could have an effect on channel erosion processes and stream profiles over geological timescales. We found that spawning can profoundly influence the longitudinal profiles of stream beds and thereby the evolution of entire watersheds. The radiation of five Pacific salmon from a common ancestor, additionally, could also cause significant geomorphic change by altering a wider section of the profile for a given distribution of grain sizes. This modeling study suggests that biological evolution can impact landscape evolution by increasing the sediment transport and erosion efficiency of mountain streams. Moreover, the physical effects of a species on its environment might be a complementary explanation for rapid radiation events in species through the creation of new habitat types. This example provides an illustrative case for thinking about the long- and short-term coupling of biotic and abiotic systems.

3D physical modeling for patterning process development

NASA Astrophysics Data System (ADS)

Sarma, Chandra; Abdo, Amr; Bailey, Todd; Conley, Will; Dunn, Derren; Marokkey, Sajan; Talbi, Mohamed

2010-03-01

In this paper we will demonstrate how a 3D physical patterning model can act as a forensic tool for OPC and ground-rule development. We discuss examples where the 2D modeling shows no issues in printing gate lines but 3D modeling shows severe resist loss in the middle. In absence of corrective measure, there is a high likelihood of line discontinuity post etch. Such early insight into process limitations of prospective ground rules can be invaluable for early technology development. We will also demonstrate how the root cause of broken poly-line after etch could be traced to resist necking in the region of STI step with the help of 3D models. We discuss different cases of metal and contact layouts where 3D modeling gives an early insight in to technology limitations. In addition such a 3D physical model could be used for early resist evaluation and selection for required ground-rule challenges, which can substantially reduce the cycle time for process development.

Biophysical processes in fibrosis. Comment on: "Towards a unified approach in the modeling of fibrosis: A review with research perspectives" by Carlo Bianca and Martine Ben Amar

NASA Astrophysics Data System (ADS)

La Porta, Caterina A. M.; Zapperi, Stefano

2016-07-01

The process of inflammation tries to protect the body after an injury due to biological causes such as the presence of pathogens or chemicals, or to physical processes such as burns or cuts. The biological rationale for this process has the main goal of eliminating the cause of the injury and then repairing the damaged tissues. We can distinguish two kinds of inflammations: acute and chronic. In acute inflammation, a series of events involving the local vascular systems, the immune system and various cells within the injured tissue work together to eradicate the harmful stimuli. If the inflammation does not resolve the problem, it can evolve into a chronic inflammation, where the type of cells involved changes and there is a simultaneous destruction and healing of the tissue from the inflammation process.

Toxic effects of prenatal exposure to alcohol, tobacco and other drugs.

PubMed

Scott-Goodwin, A C; Puerto, M; Moreno, I

2016-06-01

Tobacco, alcohol, cannabis and cocaine are the most consumed psychoactive drugs throughout the population. Prenatal exposure to these drugs could alter normal foetal development and could threaten future welfare. The main changes observed in prenatal exposure to tobacco are caused by nicotine and carbon monoxide, which can impede nutrient and oxygen exchange between mother and foetus, restricting foetal growth. Memory, learning processes, hearing and behaviour can also be affected. Alcohol may cause physical and cognitive alterations in prenatally exposed infants, fundamentally caused by altered NMDAR and GABAR activity. Tetrahydrocannabinol, the psychoactive compound of cannabis, is capable of activating CB1R, inducing connectivity deficits during the foetal brain development. This fact could be linked to behavioural and cognitive deficits. Many of the effects from prenatal cocaine exposure are caused by altered cell proliferation, migration, differentiation and dendritic growth processes. Cocaine causes long term behavioural and cognitive alterations and also affects the uteroplacental unit. Copyright © 2016 Elsevier Inc. All rights reserved.

Detonation Processes USSR

DTIC Science & Technology

1960-06-06

scientists of various countries. The Investigators addressed themselves at once to the question as to what physical process causes combustion to...same values for the r poducts of com- bustion, D is the velocity of the detonation front AB, and w is the velocity of the products of com- ,bustton... mixed with oxi- dizer and mixture is preheated; 3 -- reaction zone; 4 -- products of combustion. Let us return to the single-headed spin and consider

Transforming information from silicon testing and design characterization into numerical data sets for yield learning

NASA Astrophysics Data System (ADS)

Yang, Thomas; Shen, Yang; Zhang, Yifan; Sweis, Jason; Lai, Ya-Chieh

2017-03-01

Silicon testing results are regularly collected for a particular lot of wafers to study yield loss from test result diagnostics. Product engineers will analyze the diagnostic results and perform a number of physical failure analyses to detect systematic defects which cause yield loss for these sets of wafers in order to feedback the information to process engineers for process improvements. Most of time, the systematic defects that are detected are major issues or just one of the causes for the overall yield loss. This paper will present a working flow for using design analysis techniques combined with diagnostic methods to systematically transform silicon testing information into physical layout information. A new set of the testing results are received from a new lot of wafers for the same product. We can then correlate all the diagnostic results from different periods of time to check which blocks or nets have been highlighted or stop occurring on the failure reports in order to monitor process changes which impact the yield. The design characteristic analysis flow is also implemented to find 1) the block connections on a design that have failed electrical test or 2) frequently used cells that been highlighted multiple times.

Bluff evolution along coastal drumlins: Boston Harbor Islands, Massachusetts

USGS Publications Warehouse

Himmelstoss, E.A.; FitzGerald, D.M.; Rosen, P.S.; Allen, J.R.

2006-01-01

A series of partially drowned drumlins forms the backbone of the inner islands within Boston Harbor. The shoreline of these rounded glacial deposits is composed of actively retreating bluffs formed by continual wave attack. Comparisons of bluffs reveal variability in their height and lateral extent, as well as in the dominant mechanism causing their retreat. Two processes are responsible for bluff erosion and yield distinct bluff morphologies: (1) wave attack undercuts the bluff and causes episodic slumping, yielding planar bluff slopes, and (2) subaerial processes such as rainfall create irregular slopes characterized by rills and gullies. We propose a model of drumlin bluff evolution that is based on processes of erosion and physical characteristics such as bluff height, slope morphology, and the orientation of the bluff with respect to the long axis of the drumlin and its topographic crest. The four phases of drumlin bluff evolution consist of (1) initial formation of bluff, with retreat dominated by wave notching and slumping processes; (2) rill and gully development as bluff heights exceed 10 m and slumped sediment at bluff base inhibits wave attack; (3) return of wave notching and slumping as bluff heights decrease; and (4) final development of boulder retreat lag as last remnants of drumlin are eroded by wave action. These phases capture the important physical processes of drumlin evolution in Boston Harbor and could apply to other eroding coastal drumlin deposits.

Variation in the terrestrial isotopic composition and atomic weight of argon

USGS Publications Warehouse

Böhlke, John Karl

2014-01-01

The isotopic composition and atomic weight of argon (Ar) are variable in terrestrial materials. Those variations are a source of uncertainty in the assignment of standard properties for Ar, but they provide useful information in many areas of science. Variations in the stable isotopic composition and atomic weight of Ar are caused by several different processes, including (1) isotope production from other elements by radioactive decay (radiogenic isotopes) or other nuclear transformations (e.g., nucleogenic isotopes), and (2) isotopic fractionation by physical-chemical processes such as diffusion or phase equilibria. Physical-chemical processes cause correlated mass-dependent variations in the Ar isotope-amount ratios (40Ar/36Ar, 38Ar/36Ar), whereas nuclear transformation processes cause non-mass-dependent variations. While atmospheric Ar can serve as an abundant and homogeneous isotopic reference, deviations from the atmospheric isotopic ratios in other Ar occurrences limit the precision with which a standard atomic weight can be given for Ar. Published data indicate variation of Ar atomic weights in normal terrestrial materials between about 39.7931 and 39.9624. The upper bound of this interval is given by the atomic mass of 40Ar, as some samples contain almost pure radiogenic 40Ar. The lower bound is derived from analyses of pitchblende (uranium mineral) containing large amounts of nucleogenic 36Ar and 38Ar. Within this interval, measurements of different isotope ratios (40Ar/36Ar or 38Ar/36Ar) at various levels of precision are widely used for studies in geochronology, water–rock interaction, atmospheric evolution, and other fields.

Optical alignment procedure utilizing neural networks combined with Shack-Hartmann wavefront sensor

NASA Astrophysics Data System (ADS)

Adil, Fatime Zehra; Konukseven, Erhan İlhan; Balkan, Tuna; Adil, Ömer Faruk

2017-05-01

In the design of pilot helmets with night vision capability, to not limit or block the sight of the pilot, a transparent visor is used. The reflected image from the coated part of the visor must coincide with the physical human sight image seen through the nonreflecting regions of the visor. This makes the alignment of the visor halves critical. In essence, this is an alignment problem of two optical parts that are assembled together during the manufacturing process. Shack-Hartmann wavefront sensor is commonly used for the determination of the misalignments through wavefront measurements, which are quantified in terms of the Zernike polynomials. Although the Zernike polynomials provide very useful feedback about the misalignments, the corrective actions are basically ad hoc. This stems from the fact that there exists no easy inverse relation between the misalignment measurements and the physical causes of the misalignments. This study aims to construct this inverse relation by making use of the expressive power of the neural networks in such complex relations. For this purpose, a neural network is designed and trained in MATLAB® regarding which types of misalignments result in which wavefront measurements, quantitatively given by Zernike polynomials. This way, manual and iterative alignment processes relying on trial and error will be replaced by the trained guesses of a neural network, so the alignment process is reduced to applying the counter actions based on the misalignment causes. Such a training requires data containing misalignment and measurement sets in fine detail, which is hard to obtain manually on a physical setup. For that reason, the optical setup is completely modeled in Zemax® software, and Zernike polynomials are generated for misalignments applied in small steps. The performance of the neural network is experimented and found promising in the actual physical setup.

Insects and diseases

Treesearch

John W. Couston

2009-01-01

Insects and diseases are a natural part of forested ecosystems. Their activity is partially regulated by biotic factors, e.g., host abundance, host quality; physical factors, e.g., soil, climate; and disturbances (Berryman 1986). Insects and diseases can influence both forest patterns and forest processes by causing, for example, defoliation and mortality. These...

49 CFR 191.23 - Reporting safety-related conditions.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., controls, or processes gas or LNG. (4) Any material defect or physical damage that impairs the... strength. (5) Any malfunction or operating error that causes the pressure of a pipeline or LNG facility... structural integrity of an LNG storage tank. (8) Any safety-related condition that could lead to an imminent...

Sickness absence, marginality, and medically unexplained physical symptoms: A focus-group study of patients’ experiences

PubMed Central

2013-01-01

Abstract Purpose Medically unexplained physical symptoms (MUPS) form a major cause of sickness absence. The purpose of this study was to explore factors which may influence further marginalization among patients with MUPS on long-term sickness absence. Methods Two focus-group discussions were conducted with a purposive sample of 12 participants, six men and six women, aged 24–59 years. Their average duration of sickness absence was 10.5 months. Participants were invited to share stories about experiences from the process leading to the ongoing sickness absence, with a focus on the causes being medically unexplained. Systematic text condensation was applied for analysis. Inspired by theories of marginalization and coping, the authors searched for knowledge of how patients’ positive resources can be mobilized to counteract processes of marginality. Results Analysis revealed how invisible symptoms and lack of objective findings were perceived as an additional burden to the sickness absence itself. Factors that could counteract further marginalization were a supportive social network, positive coping strategies such as keeping to the daily schedule and physical activity, and positive attention and confidence from professionals. Conclusions Confidence from both personal and professional contacts is crucial. GPs have an important and appreciated role in this aspect. PMID:23659708

A taxonomy of explanations in a general practitioner clinic for patients with persistent "medically unexplained" physical symptoms.

PubMed

Morton, LaKrista; Elliott, Alison; Cleland, Jennifer; Deary, Vincent; Burton, Christopher

2017-02-01

To develop a taxonomy of explanations for patients with persistent physical symptoms. We analysed doctors' explanations from two studies of a moderately-intensive consultation intervention for patients with multiple, often "medically-unexplained," physical symptoms. We used a constant comparative method to develop a taxonomy which was then applied to all verbatim explanations. We analysed 138 explanations provided by five general practitioners to 38 patients. The taxonomy comprised explanation types and explanation components. Three explanation types described the overall structure of the explanations: Rational Adaptive, Automatic Adaptive, and Complex. These differed in terms of who or what was given agency within the explanation. Three explanation components described the content of the explanation: Facts - generic statements about normal or dysfunctional processes; Causes - person-specific statements about proximal or distal causes for symptoms; Mechanisms - processes by which symptoms arise or persist in the individual. Most explanations conformed to one type and contained several components. This novel taxonomy for classifying clinical explanations permits detailed classification of explanation types and content. Explanation types appear to carry different implications of agency. The taxonomy is suitable for examining explanations and developing prototype explanatory scripts in both training and research settings. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Numerical study of impact erosion of multiple solid particle

NASA Astrophysics Data System (ADS)

Zheng, Chao; Liu, Yonghong; Chen, Cheng; Qin, Jie; Ji, Renjie; Cai, Baoping

2017-11-01

Material erosion caused by continuous particle impingement during hydraulic fracturing results in significant economic loss and increased production risks. The erosion process is complex and has not been clearly explained through physical experiments. To address this problem, a multiple particle model in a 3D configuration was proposed to investigate the dynamic erosion process. This approach can significantly reduce experiment costs. The numerical model considered material damping and elastic-plastic material behavior of target material. The effects of impact parameters on erosion characteristics, such as plastic deformation, contact time, and energy loss rate, were investigated. Based on comprehensive studies, the dynamic erosion mechanism and geometry evolution of eroded crater was obtained. These findings can provide a detailed erosion process of target material and insights into the material erosion caused by multiple particle impingement.

Evolutionary biochemistry: revealing the historical and physical causes of protein properties

PubMed Central

Harms, Michael J.; Thornton, Joseph W.

2014-01-01

The repertoire of proteins and nucleic acids in the living world is determined by evolution; their properties are determined by the laws of physics and chemistry. Explanations of these two kinds of causality — the purviews of evolutionary biology and biochemistry, respectively — are typically pursued in isolation, but many fundamental questions fall squarely at the interface of fields. Here we articulate the paradigm of evolutionary biochemistry, which aims to dissect the physical mechanisms and evolutionary processes by which biological molecules diversified and to reveal how their physical architecture facilitates and constrains their evolution. We show how an integration of evolution with biochemistry moves us towards a more complete understanding of why biological molecules have the properties that they do. PMID:23864121

Understanding immunology: fun at an intersection of the physical, life, and clinical sciences

NASA Astrophysics Data System (ADS)

Chakraborty, Arup K.

2014-10-01

Understanding how the immune system works is a grand challenge in science with myriad direct implications for improving human health. The immune system protects us from infectious pathogens and cancer, and maintains a harmonious steady state with essential microbiota in our gut. Vaccination, the medical procedure that has saved more lives than any other, involves manipulating the immune system. Unfortunately, the immune system can also go awry to cause autoimmune diseases. Immune responses are the product of stochastic collective dynamic processes involving many interacting components. These processes span multiple scales of length and time. Thus, statistical mechanics has much to contribute to immunology, and the oeuvre of biological physics will be further enriched if the number of physical scientists interested in immunology continues to increase. I describe how I got interested in immunology and provide a glimpse of my experiences working on immunology using approaches from statistical mechanics and collaborating closely with immunologists.

Analysis of Occupational Accidents in Underground and Surface Mining in Spain Using Data-Mining Techniques

PubMed Central

Sanmiquel, Lluís; Bascompta, Marc; Rossell, Josep M.; Anticoi, Hernán Francisco; Guash, Eduard

2018-01-01

An analysis of occupational accidents in the mining sector was conducted using the data from the Spanish Ministry of Employment and Social Safety between 2005 and 2015, and data-mining techniques were applied. Data was processed with the software Weka. Two scenarios were chosen from the accidents database: surface and underground mining. The most important variables involved in occupational accidents and their association rules were determined. These rules are composed of several predictor variables that cause accidents, defining its characteristics and context. This study exposes the 20 most important association rules in the sector—either surface or underground mining—based on the statistical confidence levels of each rule as obtained by Weka. The outcomes display the most typical immediate causes, along with the percentage of accidents with a basis in each association rule. The most important immediate cause is body movement with physical effort or overexertion, and the type of accident is physical effort or overexertion. On the other hand, the second most important immediate cause and type of accident are different between the two scenarios. Data-mining techniques were chosen as a useful tool to find out the root cause of the accidents. PMID:29518921

Analysis of Occupational Accidents in Underground and Surface Mining in Spain Using Data-Mining Techniques.

PubMed

Sanmiquel, Lluís; Bascompta, Marc; Rossell, Josep M; Anticoi, Hernán Francisco; Guash, Eduard

2018-03-07

An analysis of occupational accidents in the mining sector was conducted using the data from the Spanish Ministry of Employment and Social Safety between 2005 and 2015, and data-mining techniques were applied. Data was processed with the software Weka. Two scenarios were chosen from the accidents database: surface and underground mining. The most important variables involved in occupational accidents and their association rules were determined. These rules are composed of several predictor variables that cause accidents, defining its characteristics and context. This study exposes the 20 most important association rules in the sector-either surface or underground mining-based on the statistical confidence levels of each rule as obtained by Weka. The outcomes display the most typical immediate causes, along with the percentage of accidents with a basis in each association rule. The most important immediate cause is body movement with physical effort or overexertion, and the type of accident is physical effort or overexertion. On the other hand, the second most important immediate cause and type of accident are different between the two scenarios. Data-mining techniques were chosen as a useful tool to find out the root cause of the accidents.

Effects of black carbon and boundary layer interaction on surface ozone in Nanjing, China

NASA Astrophysics Data System (ADS)

Gao, Jinhui; Zhu, Bin; Xiao, Hui; Kang, Hanqing; Pan, Chen; Wang, Dongdong; Wang, Honglei

2018-05-01

As an important solar radiation absorbing aerosol, the effect of black carbon (BC) on surface ozone, via reducing photolysis rate, has been widely discussed by offline model studies. However, BC-boundary layer (BL) interactions also influence surface ozone. Using the online model simulations and process analysis, we demonstrate the significant impact of BC-BL interaction on surface ozone in Nanjing. The absorbing effect of BC heats the air above the BL and suppresses and delays the development of the BL, which eventually leads to a change in surface ozone via a change in the contributions from chemical and physical processes (photochemistry, vertical mixing and advection). For chemical processes, the suppression of the BL leads to large amounts of ozone precursors being confined below the BL which has an increased effect on ozone chemical production and offsets the decrease caused by the reduction of the photolysis rate, thus enhancing ozone chemical formation from 10:00 to 12:00 LT. Furthermore, changes in physical processes, especially the vertical mixing process, show a more significant influence on surface ozone. The weakened turbulence, caused by the suppressed BL, entrains much less ozone aloft down to the surface. Finally, summing-up the changes in the processes, surface ozone reduces before noon and the maximum reduction reaches 16.4 ppb at 12:00 LT. In the afternoon, the changes in chemical process are small which inconspicuously influence surface ozone. However, change in the vertical mixing process still influences surface ozone significantly. Due to the delayed development of the BL, there are obvious ozone gradients around the top of BL. Therefore, high concentrations of ozone aloft can still be entrained down to the surface which offsets the reduction of surface ozone. Comparing the changes in the processes, the change in vertical mixing plays the most important role in impacting surface ozone. Our results highlight the great impacts BC-BL interactions have on surface ozone by influencing the ozone contribution from physical process. This suggests that more attention should be paid to the mechanism of aerosol-BL interactions when controlling ozone pollution.

Cockatiel-induced hypersensitivity pneumonitis.

PubMed

McCluskey, James D; Haight, Robert R; Brooks, Stuart M

2002-07-01

Diagnosing an environmental or occupationally related pulmonary disorder often involves a process of elimination. Unlike commonly diagnosed conditions in other specialties, a cause-and-effect relationship may be implied, yet other factors such as temporality and biologic plausibility are lacking. Our patient was referred with a suspected work-related pulmonary disorder. For several years, she had suffered with dyspnea on exertion and repeated flulike illnesses. She worked at an automobile repair garage that performed a large number of emission tests, and there was concern that her workplace exposures were the cause of her symptoms. After a careful review of her history, physical examination, and laboratory testing, we came to the conclusion that she had hypersensitivity pneumonitis related to pet cockatiels in her home. Clinical points of emphasis include the importance of a complete environmental history and careful auscultation of the chest when performing the physical examination. In addition, we encountered an interesting physical diagnostic clue, a respiratory sound that assisted with the eventual diagnosis.

Cockatiel-induced hypersensitivity pneumonitis.

PubMed Central

McCluskey, James D; Haight, Robert R; Brooks, Stuart M

2002-01-01

Diagnosing an environmental or occupationally related pulmonary disorder often involves a process of elimination. Unlike commonly diagnosed conditions in other specialties, a cause-and-effect relationship may be implied, yet other factors such as temporality and biologic plausibility are lacking. Our patient was referred with a suspected work-related pulmonary disorder. For several years, she had suffered with dyspnea on exertion and repeated flulike illnesses. She worked at an automobile repair garage that performed a large number of emission tests, and there was concern that her workplace exposures were the cause of her symptoms. After a careful review of her history, physical examination, and laboratory testing, we came to the conclusion that she had hypersensitivity pneumonitis related to pet cockatiels in her home. Clinical points of emphasis include the importance of a complete environmental history and careful auscultation of the chest when performing the physical examination. In addition, we encountered an interesting physical diagnostic clue, a respiratory sound that assisted with the eventual diagnosis. PMID:12117652

Vertically extensive and unstable magmatic systems: A unified view of igneous processes.

PubMed

Cashman, Katharine V; Sparks, R Stephen J; Blundy, Jonathan D

2017-03-24

Volcanoes are an expression of their underlying magmatic systems. Over the past three decades, the classical focus on upper crustal magma chambers has expanded to consider magmatic processes throughout the crust. A transcrustal perspective must balance slow (plate tectonic) rates of melt generation and segregation in the lower crust with new evidence for rapid melt accumulation in the upper crust before many volcanic eruptions. Reconciling these observations is engendering active debate about the physical state, spatial distribution, and longevity of melt in the crust. Here we review evidence for transcrustal magmatic systems and highlight physical processes that might affect the growth and stability of melt-rich layers, focusing particularly on conditions that cause them to destabilize, ascend, and accumulate in voluminous but ephemeral shallow magma chambers. Copyright © 2017, American Association for the Advancement of Science.

Non-equilibrium Quasi-Chemical Nucleation Model

NASA Astrophysics Data System (ADS)

Gorbachev, Yuriy E.

2018-04-01

Quasi-chemical model, which is widely used for nucleation description, is revised on the basis of recent results in studying of non-equilibrium effects in reacting gas mixtures (Kolesnichenko and Gorbachev in Appl Math Model 34:3778-3790, 2010; Shock Waves 23:635-648, 2013; Shock Waves 27:333-374, 2017). Non-equilibrium effects in chemical reactions are caused by the chemical reactions themselves and therefore these contributions should be taken into account in the corresponding expressions for reaction rates. Corrections to quasi-equilibrium reaction rates are of two types: (a) spatially homogeneous (caused by physical-chemical processes) and (b) spatially inhomogeneous (caused by gas expansion/compression processes and proportional to the velocity divergency). Both of these processes play an important role during the nucleation and are included into the proposed model. The method developed for solving the generalized Boltzmann equation for chemically reactive gases is applied for solving the set of equations of the revised quasi-chemical model. It is shown that non-equilibrium processes lead to essential deviation of the quasi-stationary distribution and therefore the nucleation rate from its traditional form.

Hydrologically driven ecosystem processes determine the distribution and persistence of ecosystem-specialist predators under climate change.

PubMed

Carroll, Matthew J; Heinemeyer, Andreas; Pearce-Higgins, James W; Dennis, Peter; West, Chris; Holden, Joseph; Wallage, Zoe E; Thomas, Chris D

2015-07-31

Climate change has the capacity to alter physical and biological ecosystem processes, jeopardizing the survival of associated species. This is a particular concern in cool, wet northern peatlands that could experience warmer, drier conditions. Here we show that climate, ecosystem processes and food chains combine to influence the population performance of species in British blanket bogs. Our peatland process model accurately predicts water-table depth, which predicts abundance of craneflies (keystone invertebrates), which in turn predicts observed abundances and population persistence of three ecosystem-specialist bird species that feed on craneflies during the breeding season. Climate change projections suggest that falling water tables could cause 56-81% declines in cranefly abundance and, hence, 15-51% reductions in the abundances of these birds by 2051-2080. We conclude that physical (precipitation, temperature and topography), biophysical (evapotranspiration and desiccation of invertebrates) and ecological (food chains) processes combine to determine the distributions and survival of ecosystem-specialist predators.

Hydrologically driven ecosystem processes determine the distribution and persistence of ecosystem-specialist predators under climate change

PubMed Central

Carroll, Matthew J.; Heinemeyer, Andreas; Pearce-Higgins, James W.; Dennis, Peter; West, Chris; Holden, Joseph; Wallage, Zoe E.; Thomas, Chris D.

2015-01-01

Climate change has the capacity to alter physical and biological ecosystem processes, jeopardizing the survival of associated species. This is a particular concern in cool, wet northern peatlands that could experience warmer, drier conditions. Here we show that climate, ecosystem processes and food chains combine to influence the population performance of species in British blanket bogs. Our peatland process model accurately predicts water-table depth, which predicts abundance of craneflies (keystone invertebrates), which in turn predicts observed abundances and population persistence of three ecosystem-specialist bird species that feed on craneflies during the breeding season. Climate change projections suggest that falling water tables could cause 56–81% declines in cranefly abundance and, hence, 15–51% reductions in the abundances of these birds by 2051–2080. We conclude that physical (precipitation, temperature and topography), biophysical (evapotranspiration and desiccation of invertebrates) and ecological (food chains) processes combine to determine the distributions and survival of ecosystem-specialist predators. PMID:26227623

Causes and remedies for porosity in composite manufacturing

NASA Astrophysics Data System (ADS)

Fernlund, G.; Wells, J.; Fahrang, L.; Kay, J.; Poursartip, A.

2016-07-01

Porosity is a challenge in virtually all composite processes but in particular in low pressure processes such as out of autoclave processing of prepregs, where the maximum pressure is one atmosphere. This paper discusses the physics behind important transport phenomena that control porosity and how we can use our understanding of the underlying science to develop strategies to achieve low porosity for these materials and processes in an industrial setting. A three step approach is outlined that addresses and discusses: gas evacuation of trapped air, volatiles and off-gassing, and resin infiltration of evacuated void space.

The Language of Coping: Understanding Filipino Geriatric Patients' Hemodialysis Lived Experiences

ERIC Educational Resources Information Center

de Guzman, Allan B.; Chy, Mark Anthony S.; Concepcion, April Faye P.; Conferido, Alvin John C.; Coretico, Kristine I.

2009-01-01

The majority of patients with chronic kidney disease (CKD) are undergoing maintenance hemodialysis. Hemodialysis is a process of removing metabolic waste, other poisons, and excess fluids from the blood and replacing essential blood constituents through a dialysis machine. With hemodialysis causing stress not only to physical status but also to…

PHYSICAL AND BIOLOGICAL CONTROLS ON DISSOLVED OXYGEN DYNAMICS IN A NORTHEASTERN GULF OF MEXICO ESTUARY

EPA Science Inventory

Nutrient over-enrichment is one of the most often cited causes of 305b impairment in coastal waters. Excessive nutrients affect designated uses of the nation's aquatic resources, and pose risks to human health and the environment. The process of developing nutrient criteria for e...

READING MANUAL, A GUIDEBOOK FOR ILLINOIS WORKSHOPS IN READING REMEDIATION.

ERIC Educational Resources Information Center

COVEY, CATHERINE

THE IMPORTANCE OF ADAPTING READING INSTRUCTION TO EACH CHILD'S NEEDS IS STRESSED IN THIS HANDBOOK FOR TEACHERS OF REMEDIAL READING. INFORMATION IS ORGANIZED AROUND SIX TOPICS--(1) THE NATURE OF THE READING PROCESS, (2) CRITERIA FOR A GOOD ELEMENTARY READING PROGRAM, (3) REMEDIAL READERS, THE SYMPTOMS AND CAUSES (PHYSICAL, INTELLECTUAL,…

Library Automation and Facility Planning.

ERIC Educational Resources Information Center

Cohen, Aaron; Cohen, Elaine

This seminar and workbook are designed to aid librarians in planning and designing attractive and efficient libraries in light of the changing technologies of the 1980s. It is based on the premise that the electronic revolution of the 1980s will cause substantial changes in the work force, work processes, and the nature of physical layouts of…

Coping with Parental Loss because of Termination of Parental Rights

ERIC Educational Resources Information Center

Schneider, Kerri M.; Phares, Vicky

2005-01-01

This article addresses the process by which children and adolescents cope with severe acute stress of parental loss from causes other than divorce or death. Participants were 60 children and adolescents from a residential treatment facility. Most had experienced neglect, physical abuse, and sexual abuse, and their parents had their parential…

Low energy physical activity recognition system on smartphones.

PubMed

Soria Morillo, Luis Miguel; Gonzalez-Abril, Luis; Ortega Ramirez, Juan Antonio; de la Concepcion, Miguel Angel Alvarez

2015-03-03

An innovative approach to physical activity recognition based on the use of discrete variables obtained from accelerometer sensors is presented. The system first performs a discretization process for each variable, which allows efficient recognition of activities performed by users using as little energy as possible. To this end, an innovative discretization and classification technique is presented based on the χ2 distribution. Furthermore, the entire recognition process is executed on the smartphone, which determines not only the activity performed, but also the frequency at which it is carried out. These techniques and the new classification system presented reduce energy consumption caused by the activity monitoring system. The energy saved increases smartphone usage time to more than 27 h without recharging while maintaining accuracy.

Determinants of business sustainability: an ergonomics perspective.

PubMed

Genaidy, Ash M; Sequeira, Reynold; Rinder, Magda M; A-Rehim, Amal D

2009-03-01

There is a need to integrate both macro- and micro-ergonomic approaches for the effective implementation of interventions designed to improve the root causes of problems such as work safety, quality and productivity in the enterprise system. The objective of this study was to explore from an ergonomics perspective the concept of business sustainability through optimising the worker-work environment interface. The specific aims were: (a) to assess the working conditions of a production department work process with the goal to jointly optimise work safety, quality and quantity; (b) to evaluate the enterprise-wide work process at the system level as a social entity in an attempt to trace the root causes of ergonomic issues impacting employees throughout the work process. The Work Compatibility Model was deployed to examine the experiences of workers (that is, effort, perceived risk/benefit, performance and satisfaction/dissatisfaction or psychological impact) and their associations with the complex domains of the work environment (task content, physical and non-physical work environment and conditions for learning/growth/development). This was followed by assessment of the enterprise system through detailed interviews with department managers and lead workers. A system diagnostic instrument was also constructed from information derived from the published literature to evaluate the enterprise system performance. The investigation of the production department indicated that the stress and musculoskeletal pain experienced by workers (particularly on the day shift) were derived from sources elsewhere in the work process. The enterprise system evaluation and detailed interviews allowed the research team to chart the feed-forward and feedback stress propagation loops in the work system. System improvement strategies were extracted on the basis of tacit/explicit knowledge obtained from department managers and lead workers. In certain situations concerning workplace human performance issues, a combined macro-micro ergonomic methodology is essential to solve the productivity, quality and safety issues impacting employees along the trajectory or path of the enterprise-wide work process. In this study, the symptoms associated with human performance issues in one production department work process had root causes originating in the customer service department work process. In fact, the issues found in the customer service department caused performance problems elsewhere in the enterprise-wide work process such as the traffic department. Sustainable enterprise solutions for workplace human performance require the integration of macro- and micro-ergonomic approaches.

PULSE: A numerical model for the simulation of snowpack solute dynamics to capture runoff ionic pulses during snowmelt

NASA Astrophysics Data System (ADS)

Costa, D.; Pomeroy, J. W.; Wheater, H. S.

2017-12-01

Early ionic pulses in spring snowmelt can cause the temporary acidification of streams and account for a significant portion of the total annual nutrient export, particularly in seasonally snow-covered areas where the frozen ground may limit runoff-soil contact and cause the rapid delivery of these ions to streams. Ionic pulses are a consequence of snow ion exclusion, a process induced by snow metamorphism where ions are segregated from the snow grains losing mass to the surface of the grains gaining mass. While numerous studies have been successful in providing quantitative evidence of this process, few mechanistic mathematical models have been proposed for diagnostic and prediction. A few early modelling attempts have been successful in capturing this process assuming transport through porous media with variable porosity, however their implementation is difficult because they require complex models of snow physics to resolve the evolution of in-snow properties and processes during snowmelt, such as heat conduction, metamorphism, melt and water flow. Furthermore, initial snowpack to snow-surface ion concentration ratios are difficult to measure but are required to initiate these models and ion exclusion processes are not represented in a physically-based transparent fashion. In this research, a standalone numerical model has been developed to capture ionic pulses in snowmelt by emulating solute leaching from snow grains during melt and its subsequent transport by the percolating meltwater. Estimating snow porosity and water content dynamics is shown to be a viable alternative to deployment of complex snow physics models for this purpose. The model was applied to four study sites located in the Arctic and in Sierra Nevada to test for different climatic and hydrological conditions. The model compares very well with observations and could capture both the timing and magnitude of early melt ionic pulses accurately. This study demonstrates how physically based approaches can provide successful simulations of the spatial and temporal fluxes of snowmelt ions, which can be used to improve the prediction of nutrient export in cold regions for the spring freshet.

PULSE: A numerical model for the simulation of snowpack solute dynamics to capture runoff ionic pulses during snowmelt

NASA Astrophysics Data System (ADS)

Clark, M. P.; Nijssen, B.; Lundquist, J. D.; Luce, C. H.; Musselman, K. N.; Wayand, N. E.; Ou, M.; Lapo, K. E.

2016-12-01

Early ionic pulses in spring snowmelt can cause the temporary acidification of streams and account for a significant portion of the total annual nutrient export, particularly in seasonally snow-covered areas where the frozen ground may limit runoff-soil contact and cause the rapid delivery of these ions to streams. Ionic pulses are a consequence of snow ion exclusion, a process induced by snow metamorphism where ions are segregated from the snow grains losing mass to the surface of the grains gaining mass. While numerous studies have been successful in providing quantitative evidence of this process, few mechanistic mathematical models have been proposed for diagnostic and prediction. A few early modelling attempts have been successful in capturing this process assuming transport through porous media with variable porosity, however their implementation is difficult because they require complex models of snow physics to resolve the evolution of in-snow properties and processes during snowmelt, such as heat conduction, metamorphism, melt and water flow. Furthermore, initial snowpack to snow-surface ion concentration ratios are difficult to measure but are required to initiate these models and ion exclusion processes are not represented in a physically-based transparent fashion. In this research, a standalone numerical model has been developed to capture ionic pulses in snowmelt by emulating solute leaching from snow grains during melt and its subsequent transport by the percolating meltwater. Estimating snow porosity and water content dynamics is shown to be a viable alternative to deployment of complex snow physics models for this purpose. The model was applied to four study sites located in the Arctic and in Sierra Nevada to test for different climatic and hydrological conditions. The model compares very well with observations and could capture both the timing and magnitude of early melt ionic pulses accurately. This study demonstrates how physically based approaches can provide successful simulations of the spatial and temporal fluxes of snowmelt ions, which can be used to improve the prediction of nutrient export in cold regions for the spring freshet.

Physical losses could partially explain modest carotenoid retention in dried food products from biofortified cassava

PubMed Central

Tomlins, Keith Ian; Chijioke, Ugo; Westby, Andrew

2018-01-01

Gari, a fermented and dried semolina made from cassava, is one of the most common foods in West Africa. Recently introduced biofortified yellow cassava containing provitamin A carotenoids could help tackle vitamin A deficiency prevalent in those areas. However there are concerns because of the low retention of carotenoids during gari processing compared to other processes (e.g. boiling). The aim of the study was to assess the levels of true retention in trans–β-carotene during gari processing and investigate the causes of low retention. Influence of processing step, processor (3 commercial processors) and variety (TMS 01/1371; 01/1368 and 01/1412) were assessed. It was shown that low true retention (46% on average) during gari processing may be explained by not only chemical losses (i.e. due to roasting temperature) but also by physical losses (i.e. due to leaching of carotenoids in discarded liquids): true retention in the liquid lost from grating negatively correlated with true retention retained in the mash (R = -0.914). Moreover, true retention followed the same pattern as lost water at the different processing steps (i.e. for the commercial processors). Variety had a significant influence on true retention, carotenoid content, and trans-cis isomerisation but the processor type had little effect. It is the first time that the importance of physical carotenoid losses was demonstrated during processing of biofortified crops. PMID:29561886

Physical losses could partially explain modest carotenoid retention in dried food products from biofortified cassava.

PubMed

Bechoff, Aurélie; Tomlins, Keith Ian; Chijioke, Ugo; Ilona, Paul; Westby, Andrew; Boy, Erick

2018-01-01

Gari, a fermented and dried semolina made from cassava, is one of the most common foods in West Africa. Recently introduced biofortified yellow cassava containing provitamin A carotenoids could help tackle vitamin A deficiency prevalent in those areas. However there are concerns because of the low retention of carotenoids during gari processing compared to other processes (e.g. boiling). The aim of the study was to assess the levels of true retention in trans-β-carotene during gari processing and investigate the causes of low retention. Influence of processing step, processor (3 commercial processors) and variety (TMS 01/1371; 01/1368 and 01/1412) were assessed. It was shown that low true retention (46% on average) during gari processing may be explained by not only chemical losses (i.e. due to roasting temperature) but also by physical losses (i.e. due to leaching of carotenoids in discarded liquids): true retention in the liquid lost from grating negatively correlated with true retention retained in the mash (R = -0.914). Moreover, true retention followed the same pattern as lost water at the different processing steps (i.e. for the commercial processors). Variety had a significant influence on true retention, carotenoid content, and trans-cis isomerisation but the processor type had little effect. It is the first time that the importance of physical carotenoid losses was demonstrated during processing of biofortified crops.

Effect of the Environment and Environmental Uncertainty on Ship Routes

DTIC Science & Technology

2012-06-01

models consisting of basic differential equations simulating the fluid dynamic process and physics of the environment. Based on Newton’s second law of...Charles and Hazel Hall, for their unconditional love and support. They were there for me during this entire process , as they have been throughout...A simple transit across the Atlantic Ocean can easily become a rough voyage if the ship encounters high winds, which in turn will cause a high sea

Low physical activity as a predictor for total and cardiovascular disease mortality in middle-aged men and women in Finland.

PubMed

Barengo, Noël C; Hu, Gang; Lakka, Timo A; Pekkarinen, Heikki; Nissinen, Aulikki; Tuomilehto, Jaakko

2004-12-01

To investigate separately for men and women whether moderate or high leisure time physical activity, occupational physical activity, and commuting activity are associated with a reduced cardiovascular disease (CVD) and all-cause mortality, independent of CVD risk factors and other forms of physical activity. Prospective follow-up of 15,853 men and 16,824 women aged 30-59 years living in eastern and south-western Finland (median follow-up time 20 years). CVD and all-cause mortality were lower (9-21%) in men and women (2-17%) who were moderately or highly physically active during leisure time. Moderate and high levels of occupational physical activity decreased CVD and all-cause mortality by 21-27% in both sexes. Women spending daily 15 min or more in walking or cycling to and from work had a reduced CVD and all-cause mortality before adjustment for occupational and leisure time physical activity. Commuting activity was not associated with CVD or all-cause mortality in men. Moderate and high levels of leisure time and occupational physical activity are associated with a reduced CVD and all-cause mortality among both sexes. Promoting already moderate levels of leisure time and occupational physical activity are essential to prevent premature CVD and all-cause mortality.

Understanding the HPV integration and its progression to cervical cancer.

PubMed

Oyervides-Muñoz, Mariel Araceli; Pérez-Maya, Antonio Alí; Rodríguez-Gutiérrez, Hazyadee Frecia; Gómez-Macias, Gabriela Sofía; Fajardo-Ramírez, Oscar Raúl; Treviño, Víctor; Barrera-Saldaña, Hugo Alberto; Garza-Rodríguez, María Lourdes

2018-07-01

Cervical cancer is one of the main causes of female cancer death worldwide, and human papilloma virus (HPV) its causal agent. To investigate viral oncogenesis several studies have focused on the effects of HPV oncoproteins E6 and E7 and the mechanisms by which these proteins stimulate the cellular transformation process. However, phenomena such as the physical state of the viral genome (episomal or integrated) and the effects of this integration on cell proliferation contribute new clues to understand how HPV infection causes carcinogenesis. New molecular technologies are currently facilitating these discoveries. This paper reviews the tumor development process initiated by HPV, recent findings on the process of viral integration into the host genome, new methods to detect HPV integration, and derived associated effects. Copyright © 2018 Elsevier B.V. All rights reserved.

Advanced Machine Learning Emulators of Radiative Transfer Models

NASA Astrophysics Data System (ADS)

Camps-Valls, G.; Verrelst, J.; Martino, L.; Vicent, J.

2017-12-01

Physically-based model inversion methodologies are based on physical laws and established cause-effect relationships. A plethora of remote sensing applications rely on the physical inversion of a Radiative Transfer Model (RTM), which lead to physically meaningful bio-geo-physical parameter estimates. The process is however computationally expensive, needs expert knowledge for both the selection of the RTM, its parametrization and the the look-up table generation, as well as its inversion. Mimicking complex codes with statistical nonlinear machine learning algorithms has become the natural alternative very recently. Emulators are statistical constructs able to approximate the RTM, although at a fraction of the computational cost, providing an estimation of uncertainty, and estimations of the gradient or finite integral forms. We review the field and recent advances of emulation of RTMs with machine learning models. We posit Gaussian processes (GPs) as the proper framework to tackle the problem. Furthermore, we introduce an automatic methodology to construct emulators for costly RTMs. The Automatic Gaussian Process Emulator (AGAPE) methodology combines the interpolation capabilities of GPs with the accurate design of an acquisition function that favours sampling in low density regions and flatness of the interpolation function. We illustrate the good capabilities of our emulators in toy examples, leaf and canopy levels PROSPECT and PROSAIL RTMs, and for the construction of an optimal look-up-table for atmospheric correction based on MODTRAN5.

Capillary thermoconcentration instability and processes of heat and mass transfer in laser technology

NASA Astrophysics Data System (ADS)

Maiorov, Vladimir S.

2002-04-01

The paper gives a description of the phenomenon that has a considerable, and often a decisive, influence on the course of physical processes under laser radiation interaction with a substance having at least one liquid phase. The explanation of the essence of this phenomenon lies at the intersection of two branches of science: mechanics of liquids and gases, and physical chemistry (thermodynamics of heterogeneous systems). Capillary thermo-concentration instability (CTCI) is present at any non-isotropic input of energy to a heterogeneous thermodynamical system having several phases. This instability manifests itself at the phase boundary and causes processes of mass transfer, redistribution of components, emergence of new phases, relaxation vibrations. This phenomenon is most pronounced in local processes at interaction of laser radiation with matter. The theory and practice of this phenomenon unite and describe a new class of effects widely spread in nature, which play a decisive role in many physical and chemical processes and find even more various spheres of practical application. A number of examples of capillary thermo- concentration instability application are given: separation of liquid mixtures to components under thermal action of laser beam; a new method of thermal silver-free photography; control of liquid metal convection in laser alloying.

Planetary quarantine

NASA Technical Reports Server (NTRS)

1971-01-01

Methods for presterilization cleaning or decontamination of spacecraft hardware to reduce microbial load, without harming materials or spacecraft components, are investigated. Three methods were considered: (1) chemicals in liquid form, relying on physical removal as well as bacterial or bacteriostatic action; (2) chemicals used in the gaseous phase, relying on bacterial activity; and (3) mechanical cleaning relying on physical removal of organisms. These methods were evaluated in terms of their effectiveness in microbial burden reduction and compatibility with spacecraft hardware. Results show chemical methods were effective against spore microorganisms but were harmful to spacecraft materials. Mechanical methods were also effective with the degree depending upon the type of instrument employed. Mechanical methods caused problems in handling the equipment, due to vacuum pressure damaging the very thin layered materials used for shielding, and the bristles used in the process caused streaks or abrasions on some spacecraft components.

Physical activity and the elderly.

PubMed

Hollmann, Wildor; Strüder, Heiko K; Tagarakis, Christos V M; King, Gerard

2007-12-01

Functional ageing processes are characterized by a loss of performance capabilities regarding coordination, flexibility, strength, speed, and endurance. The effects of ageing processes on the cardiovascular system and skeletal muscle are the foci of attention. After age 30, the maximum aerobic dynamic performance capacity decreases by an average of 8% per decade. The causes are mainly a reduction in the maximum cardiac output and decreases in capillarization and in the skeletal muscle mass. An improvement in the maximum oxygen uptake by 18% and in the aerobic-anaerobic threshold by 22% was achieved in untrained men aged 55-70 years, in a 12-week-long bicycle ergometer-training programme. The strength of the skeletal muscle decreases particularly after 50-60 years of age. The main cause is the reduction in the number of motor units and muscle fibres. Further, modifications of the endothelial function and the development of sarcopenia are of particular importance in ageing processes. General aerobic dynamic training can improve the endothelial function in old age and thus help prevent cardiovascular diseases. Strength training is most appropriate for the prevention of sarcopenia. Imaging techniques over the last 20 years have provided new findings on the influence and the significance of physical activity on the brain. We call this new interdisciplinary area 'Exercise Neuroscience'. Demands on coordination and aerobic dynamic endurance are suitable in counteracting age-related neuronal cellular loss, synapsis hypotrophy, and in improving neurogenesis and capillarization. Adjusted physical activity is thus capable of counteracting age-related changes and performance loss not only in the cardiovascular system but also in the brain.

Development of the Damage Potential resulting from Avalanche Risks, Case Study Galtür (Tyrol, Austria)

NASA Astrophysics Data System (ADS)

Keiler, M.

2003-04-01

Reports on catastrophes with high damage caused by natural hazards seem to have increased in number recently. A new trend in dealing with these natural processes leads to the integration of risk into natural hazards evaluations and approaches of integral risk management. The risk resulting from natural hazards can be derived from the combination of parameters of physical processes (intensity and recurrence probability) and damage potential (probability of presence and expected damage value). Natural hazard research focuses mainly on the examination, modelling and estimation of individual geomorphological processes as well as on future developments caused by climate change. Even though damage potential has been taken into account more frequently, quantifying statements are still missing. Due to the changes of the socio-economic structures in mountain regions (urban sprawl, population growth, increased mobility and tourism) these studies are mandatory. This study presents a conceptual method that records the damage potential (probability of physical presence, evaluation of buildings) and shows the development of the damage potential resulting from avalanches since 1950. The study area is the community of Galtür, Austria. 36 percent of the existing buildings are found in officially declared avalanche hazard zones. The majority of these buildings are either agricultural or accommodation facilities. Additionally, the effects of physical planning and/or technical measures on the spatial development of the potential damage are illustrated. The results serve to improve risk determination and point out an unnoticed increase of damage potential and risk in apparently safe settlement areas.

LANDPLANER (LANDscape, Plants, LANdslide and ERosion): a model to describe the dynamic response of slopes (or basins) under different changing scenarios

NASA Astrophysics Data System (ADS)

Rossi, Mauro; Torri, Dino; Santi, Elisa; Bacaro, Giovanni; Marchesini, Ivan

2014-05-01

Landslide phenomena and erosion processes are widespread and cause every year extensive damages to the environment and sensible reduction of ecosystem services. These processes are in competition among them, and their complex interaction control the landscapes evolution. Landslide phenomena and erosion processes can be strongly influenced by land use, vegetation, soil characteristics and anthropic actions. Such type of phenomena are mainly model separately using empirical and physically based approaches. The former rely upon the identification of simple empirical laws correlating/relating the occurrence of instability processes to some of their potential causes. The latter are based on physical descriptions of the processes, and depending on the degree of complexity they can integrate different variables characterizing the process and their trigger. Those model often couple an hydrological model with an erosion or a landslide model. The spatial modeling schemas are heterogeneous, but mostly the raster (i.e. matrices of data) or the conceptual (i.e. cascading planes and channels) description of the terrain are used. The two model types are generally designed and applied at different scales. Empirical models, less demanding in terms of input data cannot consider explicitly the real process triggering mechanisms and commonly they are exploited to assess the potential occurrence of instability phenomena over large areas (small scale assessment). Physically-based models are high-demanding in term of input data, difficult to obtain over large areas if not with large uncertainty, and their applicability is often limited to small catchments or single slopes (large scale assessment). More those models, even if physically-based, are simplified description of the instability processes and can neglect significant issues of the real triggering mechanisms. For instance the influence of vegetation has been considered just partially. Although in the literature a variety of model approaches have been proposed to model separately landslide and erosion processes, only few attempts were made to model both jointly, mostly integrating pre-existing models. To overcome this limitation we develop a new model called LANDPLANER (LANDscape, Plants, LANdslide and ERosion), specifically design to describe the dynamic response of slopes (or basins) under different changing scenarios including: (i) changes of meteorological factors, (ii) changes of vegetation or land-use, (iii) and changes of slope morphology. The was applied in different study area in order to check its basic assumptions, and to test its general operability and applicability. Results show a reasonable model behaviors and confirm its easy applicability in real cases.

"Dis-able bodied" or "dis-able minded": stakeholders' return-to-work experiences compared between physical and mental health conditions.

PubMed

Vossen, Emmie; Van Gestel, Nicolette; Van der Heijden, Beatrice I J M; Rouwette, Etiënne A J A

2017-05-01

This study aimed to explore if and why the return-to-work (RTW) experiences of various workplace stakeholders in the Netherlands and Denmark differ between physical and mental health conditions, and to understand the consequences of potentially different experiences for the RTW process in both health conditions. We studied 21 cases of long-term sickness absence, and held a total of 61 semi-structured interviews with the various actors involved in these cases. Physical cases were seen as "easy" and mental cases as "difficult" to manage, based on the visibility and predictability of health complaints. On this ground, assessing work ability and following required RTW actions were perceived as more urgent in mental than in physical cases. Despite these perceptions, in practice, the assessment of work ability seemed to impair the RTW process in mental cases (but not in physical ones), and the (non-)uptake of RTW actions appeared to have similar results in both mental and physical cases. With these outcomes, the effectiveness of a differential approach is questioned, and the relevance of a bidirectional dialog on work ability and a phased RTW plan is highlighted, regardless of the absence cause. Our study also demonstrates how policymakers need to strike a balance between obligatory and permissive legislation to better involve workplaces in RTW issues. Implications for rehabilitation Both physically and mentally sick-listed employees could benefit from a bidirectional dialog on work ability as well as from a phased RTW plan. A greater role for employers in the RTW process should be accompanied with a support for sick-listed employees, in both physical and mental sickness absence cases. Dutch and Danish RTW legislation could be improved by carefully balancing obligatory and permissive rules and regulations to involve workplaces in RTW matters.

Occupational and leisure time physical activity: risk of all-cause mortality and myocardial infarction in the Copenhagen City Heart Study. A prospective cohort study

PubMed Central

Marott, Jacob Louis; Gyntelberg, Finn; Søgaard, Karen; Suadicani, Poul; Mortensen, Ole S; Prescott, Eva; Schnohr, Peter

2012-01-01

Objectives Men with low physical fitness and high occupational physical activity are recently shown to have an increased risk of cardiovascular disease and all-cause mortality. The association between occupational physical activity with cardiovascular disease and all-cause mortality may also depend on leisure time physical activity. Design A prospective cohort study. Setting The Copenhagen City Heart Study. Participants 7819 men and women aged 25–66 years without a history of cardiovascular disease who attended an initial examination in the Copenhagen City Heart Study in 1976–1978. Outcome measures Myocardial infarction and all-cause mortality. Occupational physical activity was defined by combining information from baseline (1976–1978) with reassessment in 1981–1983. Conventional risk factors were controlled for in Cox analyses. Results During the follow-up from 1976 to 1978 until 2010, 2888 subjects died of all-cause mortality and 787 had a first event of myocardial infarction. Overall, occupational physical activity predicted all-cause mortality and myocardial infarction in men but not in women (test for interaction p=0.02). High occupational physical activity was associated with an increased risk of all-cause mortality among men with low (HR 1.56; 95% CI 1.11 to 2.18) and moderate (HR 1.31; 95% CI 1.05 to 1.63) leisure time physical activity but not among men with high leisure time physical activity (HR 1.00; 95% CI 0.78 to 1.26) (test for interaction p=0.04). Similar but weaker tendencies were found for myocardial infarction. Among women, occupational physical activity was not associated with subsequent all-cause mortality or myocardial infarction. Conclusions The findings suggest that high occupational physical activity imposes harmful effects particularly among men with low levels of leisure time physical activity. PMID:22331387

The Nature of Self-Regulatory Fatigue and "Ego Depletion": Lessons From Physical Fatigue.

PubMed

Evans, Daniel R; Boggero, Ian A; Segerstrom, Suzanne C

2015-07-30

Self-regulation requires overriding a dominant response and leads to temporary self-regulatory fatigue. Existing theories of the nature and causes of self-regulatory fatigue highlight physiological substrates such as glucose, or psychological processes such as motivation, but these explanations are incomplete on their own. Historically, theories of physical fatigue demonstrate a similar pattern of useful but incomplete explanations, as recent views of physical fatigue emphasize the roles of both physiological and psychological factors. In addition to accounting for multiple inputs, these newer views also explain how fatigue can occur even in the presence of sufficient resources. Examining these newer theories of physical fatigue can serve as a foundation on which to build a more comprehensive understanding of self-regulatory fatigue that integrates possible neurobiological underpinnings of physical and self-regulatory fatigue, and suggests the possible function of self-regulatory fatigue. © 2015 by the Society for Personality and Social Psychology, Inc.

The nature of self-regulatory fatigue and “ego depletion”: Lessons from physical fatigue

PubMed Central

Evans, Daniel R.; Boggero, Ian A.; Segerstrom, Suzanne C.

2016-01-01

Self-regulation requires overriding a dominant response, and leads to temporary self-regulatory fatigue. Existing theories of the nature and causes of self-regulatory fatigue highlight physiological substrates such as glucose or psychological processes such as motivation, but these explanations are incomplete on their own. Historically, theories of physical fatigue demonstrate a similar pattern of useful but incomplete explanations, as recent views of physical fatigue emphasize the roles of both physiological and psychological factors. In addition to accounting for multiple inputs, these newer views also explain how fatigue can occur even in the presence of sufficient resources. Examining these newer theories of physical fatigue can serve as a foundation on which to build a more comprehensive understanding of self-regulatory fatigue that integrates possible neurobiological underpinnings of physical and self-regulatory fatigue, and suggests the possible function of self-regulatory fatigue. PMID:26228914

Geological Implications of a Physical Libration on Enceladus

NASA Technical Reports Server (NTRS)

Hurford, T. A.; Bills, B. G.; Helfenstein, P.; Greenberg, R.; Hoppa, G. V.; Hamilton, D. P.

2008-01-01

Given the non-spherical shape of Enceladus (Thomas et al., 2007), the satellite will experience gravitational torques that will cause it to physically librate as it orbits Saturn. Physical libration would produce a diurnal oscillation in the longitude of Enceladus tidal bulge which, could have a profound effect on the diurnal stresses experienced by the surface of the satellite. Although Cassini ISS has placed an observational upper limit on Enceladus libration amplitude of F < 1.5deg (Porco et al., 2006), smaller amplitudes can still have geologically significant consequences. Here we present the first detailed description of how physical libration affects tidal stresses and how those stresses then might affect geological processes including crack formation and propagation, south polar eruption activity, and tidal heating. Our goal is to provide a framework for testing the hypothesis that geologic features on Enceladus are produced by tidal stresses from diurnal physical and optical librations of the satellite.

Morphology and proteome characterization of the salivary glands of the western chinch bug, Blissus occiduus (Hemiptera: Blissidae)

USDA-ARS?s Scientific Manuscript database

The western chinch bug, Blissus occiduus Barber, is a serious pest of buffalograss due to physical and chemical damage caused during the feeding process. Although previous work has investigated the feeding behaviors of chinch bugs in the Blissus complex, no study to date has explored salivary gland ...

Erratum: Erratum to: Journal of the Korean Physical Society, Vol. 71, No. 10

NASA Astrophysics Data System (ADS)

Shin, Dong Hee; Heo, Jin Hyuck; Im, Sang Hyuk; Lee, Rena; Kim, Kyubo; Cho, Samju; Lim, Sangwook; Lee, Suk; Shim, Jang Bo; Huh, Hyun Do; Lee, Sang Hoon; Ahn, Sohyun; Nobi, Ashadun; Lee, Jae Woo; Lim, Hyunwoo; Lee, Hunwoo; Cho, Hyosung; Seo, Changwoo; Je, Uikyu; Park, Chulkyu; Kim, Kyuseok; Kim, Guna; Park, Soyoung; Lee, Dongyeon; Kang, Seokyoon; Lee, Minsik; Cao, Jingtai; Zhao, Xiaohui; Li, Zhaokun; Liu, Wei; Gu, Haijun; Kang, In Ho; Na, Moon Kyong; Seok, Ogyun; Moon, Jeong Hyun; Kim, H. W.; Kim, Sang Cheol; Bahng, Wook; Kim, Nam Kyun; Park, Him-Chan; Yang, Chang Heon; Kim, Kyungil; Kim, Youngman; Lee, Kang Seog; Hong, Yoo-Seung; Cho, Chun-Hyung; Sung, Hyuk-Kee; Hyun, June-Won; Kim, Gang Bae; Lee, Ju Ho; Kim, Yeon Jung; Hwang, Seungjin; Jeong, Jihoon; Cho, Seryeyohan; Lee, Jongmin; Yu, Tae Jun; Lee, Kang Il; Lee, Geon Joon; Park, Gyungsoon; Choi, Eun Ha; Kim, Dong-Hwan; Jeong, Jun-Seok; Eom, Su-Keun; Lee, Jae-Gil; Seo, Kwang-Seok; Cha, Ho-Young; Ko, Young Joon; Kim, Hyun Soo; Jung, Jong Hoon; Jeong, Inho; Song, Hyunwook; Lee, B. C.; Jang, Hyunchul; Kim, Byongju; Koo, Sangmo; Park, Seran; Ko, Dae-Hong; Ahn, Kwang Jun; Cho, Sungwan; Kim, Sang Goon; Hong, Kimin; Shim, Seung-Bo; Jo, Myunglae; Cho, Sung Un; Park, Yun Daniel; Kim, Hee-Cheol; Kim, Seok

2017-12-01

Regrettably, due to a technical error during the production process, there were discrepancies in DOI of the mentioned articles between HTML and PDF files. The DOIs are correct in the PDF files but were incorrect in HTML. The original articles have been corrected. The Publisher apologizes for any inconvenience and confusion caused.

Metabolic disorders causing childhood ataxia.

PubMed

Parker, Colette C; Evans, Owen B

2003-09-01

Ataxia is a common neurologic finding in many disease processes of the nervous system, and has classically been associated with numerous metabolic disorders. An error of metabolism should be considered when the ataxia is either intermittent or progressive. Acute exacerbation or worsening after high protein ingestion, concurrent febrile illness, or other physical stress is also suggestive. A positive family history can be an important diagnostic clue. Progressive molecular and biochemical techniques are revolutionizing this area of medicine, and there has been rapid advancement in understanding of the disease processes.

Influence of different natural physical fields on biological processes

NASA Astrophysics Data System (ADS)

Mashinsky, A. L.

2001-01-01

In space flight conditions gravity, magnetic, and electrical fields as well as ionizing radiation change both in size, and in direction. This causes disruptions in the conduct of some physical processes, chemical reactions, and metabolism in living organisms. In these conditions organisms of different phylogenetic level change their metabolic reactions undergo changes such as disturbances in ionic exchange both in lower and in higher plants, changes in cell morphology for example, gyrosity in Proteus ( Proteus vulgaris), spatial disorientation in coleoptiles of Wheat ( Triticum aestivum) and Pea ( Pisum sativum) seedlings, mutational changes in Crepis ( Crepis capillaris) and Arabidopsis ( Arabidopsis thaliana) seedling. It has been found that even in the absence of gravity, gravireceptors determining spatial orientation in higher plants under terrestrial conditions are formed in the course of ontogenesis. Under weightlessness this system does not function and spatial orientation is determined by the light flux gradient or by the action of some other factors. Peculiarities of the formation of the gravireceptor apparatus in higher plants, amphibians, fish, and birds under space flight conditions have been observed. It has been found that the system in which responses were accompanied by phase transition have proven to be gravity-sensitive under microgravity conditions. Such reactions include also the process of photosynthesis which is the main energy production process in plants. In view of the established effects of microgravity and different natural physical fields on biological processes, it has been shown that these processes change due to the absence of initially rigid determination. The established biological effect of physical fields influence on biological processes in organisms is the starting point for elucidating the role of gravity and evolutionary development of various organisms on Earth.

The association of physical activity with all-cause, cardiovascular, and cancer mortalities among older adults.

PubMed

Wu, Chen-Yi; Hu, Hsiao-Yun; Chou, Yi-Chang; Huang, Nicole; Chou, Yiing-Jenq; Li, Chung-Pin

2015-03-01

To evaluate the association of physical activity with all-cause, cardiovascular, and cancer mortalities among older adults. A study sample consisting of 77,541 community-dwelling Taipei citizens aged ≥ 65 years was selected based on data obtained from the government-sponsored Annual Geriatric Health Examination Program between 2006 and 2010. Subjects were asked how many times they had physical activity for ≥ 30 min during the past 6 months. Mortality was determined by matching cohort identifications with national death files. Compared to subjects with no physical activity, those who had 1-2 times of physical activity per week had a decreased risk of all-cause mortality [hazard ratio (HR): 0.77; 95% confidence interval (CI): 0.71-0.85). Subjects with 3-5 times of physical activity per week had a further decreased risk of all-cause mortality (HR: 0.64; 95% CI: 0.58-0.70). An inverse dose-response relationship was observed between physical activity and all-cause, cardiovascular, and cancer mortality. According to stratified analyses, physical activity was associated with a decreased risk of mortality in most subgroups. Physical activity had an inverse association with all-cause, cardiovascular, and cancer mortality among older adults. Furthermore, most elderly people can benefit from an active lifestyle. Copyright © 2015 Elsevier Inc. All rights reserved.

Disappearance and disintegration of comets

NASA Technical Reports Server (NTRS)

Sekanina, Z.

1984-01-01

The present investigation has the objective to provide a summary of the existing evidence on the disappearance of comets and to draw conclusions regarding the physical processes involved in the disappearance. Information concerning the classification of evidence and the causes of apparent disappearance of comets is presented in a table. Attention is given to the dissipating comets, the headless sungrazing comet 1887 I, and the physical behavior of the dissipating comets and the related phenomena. It is found that all comets confined to the planetary region of the solar system decay on astronomically short time scales. However, only some of them appear to perish catastrophically. Some of the observed phenomena could be successfully interpreted. But little insight has been obtained into the character of the processes which the dissipating comets experience.

"…you earn money by suffering pain:" Beliefs About Carpal Tunnel Syndrome Among Latino Poultry Processing Workers.

PubMed

Arcury, Thomas A; Mora, Dana C; Quandt, Sara A

2015-06-01

The nature of poultry processing puts workers at risk for developing neurological injuries, particularly carpal tunnel syndrome (CTS). Many poultry processing workers are Latino immigrants. This qualitative analysis uses an explanatory models of illness (EMs) framework to describe immigrant Latino poultry processing workers' (Guatemalan and Mexican) beliefs of CTS. Understanding these workers' CTS EMs provides a foundation for recommendations to reduce the risk factors for this occupational injury. In-depth interviews were completed with 15 poultry processing workers diagnosed with CTS. Systematic qualitative analysis was used to delineate beliefs about causes, symptoms, physiology, treatments, quality-of-life and health implications of CTS. Participants' EMs largely reflect current biomedical understanding of CTS. These EMs are similar for Guatemalan and Mexican workers. Beliefs about causes include factors in the work environment (e.g., repetition, cold) and individual physical weakness. Treatments include over-the-counter medicine, as well as traditional remedies. Most know the future impact of CTS will include chronic pain. These workers know what causes CTS and that curing it would require quitting their jobs, but feel that they must endure CTS to support their families. Latino poultry processing workers, whether Guatemalan or Mexican, have a fairly complete understanding of what causes CTS, how to treat it, and what they must do to cure it. However, situational factors force them to endure CTS. Policy changes are needed to change the structure of work in poultry processing, particularly line speed and break frequency, if the prevalence of CTS is to be reduced.

Meat consumption and mortality--results from the European Prospective Investigation into Cancer and Nutrition.

PubMed

Rohrmann, Sabine; Overvad, Kim; Bueno-de-Mesquita, H Bas; Jakobsen, Marianne U; Egeberg, Rikke; Tjønneland, Anne; Nailler, Laura; Boutron-Ruault, Marie-Christine; Clavel-Chapelon, Françoise; Krogh, Vittorio; Palli, Domenico; Panico, Salvatore; Tumino, Rosario; Ricceri, Fulvio; Bergmann, Manuela M; Boeing, Heiner; Li, Kuanrong; Kaaks, Rudolf; Khaw, Kay-Tee; Wareham, Nicholas J; Crowe, Francesca L; Key, Timothy J; Naska, Androniki; Trichopoulou, Antonia; Trichopoulos, Dimitirios; Leenders, Max; Peeters, Petra H M; Engeset, Dagrun; Parr, Christine L; Skeie, Guri; Jakszyn, Paula; Sánchez, María-José; Huerta, José M; Redondo, M Luisa; Barricarte, Aurelio; Amiano, Pilar; Drake, Isabel; Sonestedt, Emily; Hallmans, Göran; Johansson, Ingegerd; Fedirko, Veronika; Romieux, Isabelle; Ferrari, Pietro; Norat, Teresa; Vergnaud, Anne C; Riboli, Elio; Linseisen, Jakob

2013-03-07

Recently, some US cohorts have shown a moderate association between red and processed meat consumption and mortality supporting the results of previous studies among vegetarians. The aim of this study was to examine the association of red meat, processed meat, and poultry consumption with the risk of early death in the European Prospective Investigation into Cancer and Nutrition (EPIC). Included in the analysis were 448,568 men and women without prevalent cancer, stroke, or myocardial infarction, and with complete information on diet, smoking, physical activity and body mass index, who were between 35 and 69 years old at baseline. Cox proportional hazards regression was used to examine the association of meat consumption with all-cause and cause-specific mortality. As of June 2009, 26,344 deaths were observed. After multivariate adjustment, a high consumption of red meat was related to higher all-cause mortality (hazard ratio (HR) = 1.14, 95% confidence interval (CI) 1.01 to 1.28, 160+ versus 10 to 19.9 g/day), and the association was stronger for processed meat (HR = 1.44, 95% CI 1.24 to 1.66, 160+ versus 10 to 19.9 g/day). After correction for measurement error, higher all-cause mortality remained significant only for processed meat (HR = 1.18, 95% CI 1.11 to 1.25, per 50 g/d). We estimated that 3.3% (95% CI 1.5% to 5.0%) of deaths could be prevented if all participants had a processed meat consumption of less than 20 g/day. Significant associations with processed meat intake were observed for cardiovascular diseases, cancer, and 'other causes of death'. The consumption of poultry was not related to all-cause mortality. The results of our analysis support a moderate positive association between processed meat consumption and mortality, in particular due to cardiovascular diseases, but also to cancer.

Meat consumption and mortality - results from the European Prospective Investigation into Cancer and Nutrition

PubMed Central

2013-01-01

Background Recently, some US cohorts have shown a moderate association between red and processed meat consumption and mortality supporting the results of previous studies among vegetarians. The aim of this study was to examine the association of red meat, processed meat, and poultry consumption with the risk of early death in the European Prospective Investigation into Cancer and Nutrition (EPIC). Methods Included in the analysis were 448,568 men and women without prevalent cancer, stroke, or myocardial infarction, and with complete information on diet, smoking, physical activity and body mass index, who were between 35 and 69 years old at baseline. Cox proportional hazards regression was used to examine the association of meat consumption with all-cause and cause-specific mortality. Results As of June 2009, 26,344 deaths were observed. After multivariate adjustment, a high consumption of red meat was related to higher all-cause mortality (hazard ratio (HR) = 1.14, 95% confidence interval (CI) 1.01 to 1.28, 160+ versus 10 to 19.9 g/day), and the association was stronger for processed meat (HR = 1.44, 95% CI 1.24 to 1.66, 160+ versus 10 to 19.9 g/day). After correction for measurement error, higher all-cause mortality remained significant only for processed meat (HR = 1.18, 95% CI 1.11 to 1.25, per 50 g/d). We estimated that 3.3% (95% CI 1.5% to 5.0%) of deaths could be prevented if all participants had a processed meat consumption of less than 20 g/day. Significant associations with processed meat intake were observed for cardiovascular diseases, cancer, and 'other causes of death'. The consumption of poultry was not related to all-cause mortality. Conclusions The results of our analysis support a moderate positive association between processed meat consumption and mortality, in particular due to cardiovascular diseases, but also to cancer. PMID:23497300

Nature as a network of morphological infocomputational processes for cognitive agents

NASA Astrophysics Data System (ADS)

Dodig-Crnkovic, Gordana

2017-01-01

This paper presents a view of nature as a network of infocomputational agents organized in a dynamical hierarchy of levels. It provides a framework for unification of currently disparate understandings of natural, formal, technical, behavioral and social phenomena based on information as a structure, differences in one system that cause the differences in another system, and computation as its dynamics, i.e. physical process of morphological change in the informational structure. We address some of the frequent misunderstandings regarding the natural/morphological computational models and their relationships to physical systems, especially cognitive systems such as living beings. Natural morphological infocomputation as a conceptual framework necessitates generalization of models of computation beyond the traditional Turing machine model presenting symbol manipulation, and requires agent-based concurrent resource-sensitive models of computation in order to be able to cover the whole range of phenomena from physics to cognition. The central role of agency, particularly material vs. cognitive agency is highlighted.

Effect of processing on nutritive values of milk protein.

PubMed

Borad, Sanket G; Kumar, Anuj; Singh, Ashish K

2017-11-22

Milk is an essential source of nutritionally excellent quality protein in human, particularly in vegan diet. Before consumption, milk is invariably processed depending upon final product requirement. This processing may alter the nutritive value of protein in a significant manner. The processing operations like thermal treatment, chemical treatment, biochemical processing, physical treatments, nonconventional treatments, etc. may exert positive or negative influence on nutritional quality of milk proteins. On one side, processing enhances the nutritive and therapeutic values of protein while on other side intermediate or end products generated during protein reactions may cause toxicity and/or antigenicity upon consumption at elevated level. The review discusses the changes occurring in nutritive quality of milk proteins under the influence of various processing operations.

Accelerometer-determined physical activity and all-cause mortality in a national prospective cohort study of hypertensive adults.

PubMed

Loprinzi, Paul D

2016-05-01

Research in the general population suggests an inverse association between physical activity and all-cause mortality. Less research on this topic has been conducted among hypertensive adults, but the limited studies also suggest an inverse association between physical activity and all-cause mortality among hypertensive adults. At this point, sex-specific differences are not well understood, and all of the physical activity-mortality studies among hypertensive adults have employed a self-report measure of physical activity. Therefore, the purpose of this study was to examine the sex-specific association between objectively measured physical activity and all-cause mortality among a national sample of hypertensive adults. Data from the 2003 to 2006 National Health and Nutrition Examination Survey, with follow-up through 2011, were employed. Hypertension status was defined using measured blood pressure and use of blood pressure-lowering medication. Physical activity was assessed via accelerometry. After adjustments, for every 60-min increase in physical activity, hypertensive adults had a 19% (hazard rate = 0.81; 95% confidence interval: 0.72-0.91) reduced risk of all-cause mortality. There was also evidence of a dose-response relationship. Compared with those in the lowest tertile, those in the middle and upper tertiles had a 31 and 42% reduced all-cause mortality risk, respectively. There was no evidence of a sex-specific interaction effect. Among hypertensive adults, objectively measured physical activity is associated with all-cause mortality risk in a dose-response manner.

Journeys in The Country of The Blind: Entanglement Theory and The Effects of Blinding on Trials of Homeopathy and Homeopathic Provings

PubMed Central

2007-01-01

The idea of quantum entanglement is borrowed from physics and developed into an algebraic argument to explain how double-blinding randomized controlled trials could lead to failure to provide unequivocal evidence for the efficacy of homeopathy, and inability to distinguish proving and placebo groups in homeopathic pathogenic trials. By analogy with the famous double-slit experiment of quantum physics, and more modern notions of quantum information processing, these failings are understood as blinding causing information loss resulting from a kind of quantum superposition between the remedy and placebo. PMID:17342236

Physical Properties of Nyamplung Oil (Calophyllum inophyllum L) for Biodiesel Production

NASA Astrophysics Data System (ADS)

Dewang, Syamsir; Suriani; Hadriani, Siti; Bannu; Abdullah, B.

2017-05-01

Worldwide energy crisis due to the too high of energy consumption causes the people trying to find alternative energy to support energy requirements. The use of energy from environmentally friendly plant-based materials into an effort to assist communities in sufficient of national energy needs. Some processing of Nyamplung (Calophyllum inophyllum L) oil production is drying and pressing to produce crude oil. Degumming process is then performed to remove the sap contained in the oil. The next process is to remove free fatty acids (FFA) below 2% that can cause corrosion on the machine when in use. The results performed of the density properties quality to produce oil that appropriate with the international standards by time variation of catalyst. The result was obtained the density value of 0.92108 gr/cm3 at the time of 3 hours by trans-esterification process, and the best yield value was measured at 98.2% in 2 hours stirring of transesterification.

Rising tides, cumulative impacts and cascading changes to estuarine ecosystem functions.

PubMed

O'Meara, Theresa A; Hillman, Jenny R; Thrush, Simon F

2017-08-31

In coastal ecosystems, climate change affects multiple environmental factors, yet most predictive models are based on simple cause-and-effect relationships. Multiple stressor scenarios are difficult to predict because they can create a ripple effect through networked ecosystem functions. Estuarine ecosystem function relies on an interconnected network of physical and biological processes. Estuarine habitats play critical roles in service provision and represent global hotspots for organic matter processing, nutrient cycling and primary production. Within these systems, we predicted functional changes in the impacts of land-based stressors, mediated by changing light climate and sediment permeability. Our in-situ field experiment manipulated sea level, nutrient supply, and mud content. We used these stressors to determine how interacting environmental stressors influence ecosystem function and compared results with data collected along elevation gradients to substitute space for time. We show non-linear, multi-stressor effects deconstruct networks governing ecosystem function. Sea level rise altered nutrient processing and impacted broader estuarine services ameliorating nutrient and sediment pollution. Our experiment demonstrates how the relationships between nutrient processing and biological/physical controls degrade with environmental stress. Our results emphasise the importance of moving beyond simple physically-forced relationships to assess consequences of climate change in the context of ecosystem interactions and multiple stressors.

Synchronized mammalian cell culture: part I--a physical strategy for synchronized cultivation under physiological conditions.

PubMed

Barradas, Oscar Platas; Jandt, Uwe; Becker, Max; Bahnemann, Janina; Pörtner, Ralf; Zeng, An-Ping

2015-01-01

Conventional analysis and optimization procedures of mammalian cell culture processes mostly treat the culture as a homogeneous population. Hence, the focus is on cell physiology and metabolism, cell line development, and process control strategy. Impact on cultivations caused by potential variations in cellular properties between different subpopulations, however, has not yet been evaluated systematically. One main cause for the formation of such subpopulations is the progress of all cells through the cell cycle. The interaction of potential cell cycle specific variations in the cell behavior with large-scale process conditions can be optimally determined by means of (partially) synchronized cultivations, with subsequent population resolved model analysis. Therefore, it is desirable to synchronize a culture with minimal perturbation, which is possible with different yield and quality using physical selection methods, but not with frequently used chemical or whole-culture methods. Conventional nonsynchronizing methods with subsequent cell-specific, for example, flow cytometric analysis, can only resolve cell-limited effects of the cell cycle. In this work, we demonstrate countercurrent-flow centrifugal elutriation as a useful physical method to enrich mammalian cell populations within different phases of a cell cycle, which can be further cultivated for synchronized growth in bioreactors under physiological conditions. The presented combined approach contrasts with other physical selection methods especially with respect to the achievable yield, which makes it suitable for bioreactor scale cultivations. As shown with two industrial cell lines (CHO-K1 and human AGE1.HN), synchronous inocula can be obtained with overall synchrony degrees of up to 82% in the G1 phase, 53% in the S phase and 60% in the G2/M phase, with enrichment factors (Ysync) of 1.71, 1.79, and 4.24 respectively. Cells are able to grow with synchrony in bioreactors over several cell cycles. This strategy, combined with population-resolved model analysis and parameter extraction as described in the accompanying paper, offers new possibilities for studies of cell lines and processes at levels of cell cycle and population under physiological conditions. © 2014 American Institute of Chemical Engineers.

Diagnostic overshadowing and other challenges involved in the diagnostic process of patients with mental illness who present in emergency departments with physical symptoms--a qualitative study.

PubMed

Shefer, Guy; Henderson, Claire; Howard, Louise M; Murray, Joanna; Thornicroft, Graham

2014-01-01

We conducted a qualitative study in the Emergency Departments (EDs) of four hospitals in order to investigate the perceived scope and causes of 'diagnostic overshadowing'--the misattribution of physical symptoms to mental illness--and other challenges involved in the diagnostic process of people with mental illness who present in EDs with physical symptoms. Eighteen doctors and twenty-one nurses working in EDs and psychiatric liaisons teams in four general hospitals in the UK were interviewed. Interviewees were asked about cases in which mental illness interfered with diagnosis of physical problems and about other aspects of the diagnostic process. Interviews were transcribed and analysed thematically. Interviewees reported various scenarios in which mental illness or factors related to it led to misdiagnosis or delayed treatment with various degrees of seriousness. Direct factors which may lead to misattribution in this regard are complex presentations or aspects related to poor communication or challenging behaviour of the patient. Background factors are the crowded nature of the ED environment, time pressures and targets and stigmatising attitudes held by a minority of staff. The existence of psychiatric liaison team covering the ED twenty-four hours a day, seven days a week, can help reduce the risk of misdiagnosis of people with mental illness who present with physical symptoms. However, procedures used by emergency and psychiatric liaison staff require fuller operationalization to reduce disagreement over where responsibilities lie.

Wave-Current Conditions and Navigation Safety at an Inlet Entrance

DTIC Science & Technology

2015-06-26

effects of physical processes. Wave simulations with refraction, shoaling, and breaking provide estimates of wave-related parameters of interest to...summer and winter months and to better understand the cause- effect relationship between navigability conditions at Tillamook Inlet and characteristics of...the Coriolis force, wind stress, wave stress, bottom stress, vegetation flow drag, bottom friction, wave roller, and turbulent diffusion. Governing

Building of Projecting Competence among Future Teachers in the Conditions of Introduction of Inclusive Education

ERIC Educational Resources Information Center

Ketrish, Evgeniya V.; Dorozhkin, Evgenij M.; Permyakov, ?leg ?.; Tretyakova, Natalia V.; Andryukhina, Tatiana V.; Mantulenko, Valentina V.

2016-01-01

The relevance of the researched problem is caused by the need of consideration of teachers' readiness for work in the conditions of inclusive education, and change of process of their professional training (on the example of specialists in the sphere of physical education). The purpose of publication consists in the development of pedagogical…

Ram-pressure feeding of supermassive black holes.

PubMed

Poggianti, Bianca M; Jaffé, Yara L; Moretti, Alessia; Gullieuszik, Marco; Radovich, Mario; Tonnesen, Stephanie; Fritz, Jacopo; Bettoni, Daniela; Vulcani, Benedetta; Fasano, Giovanni; Bellhouse, Callum; Hau, George; Omizzolo, Alessandro

2017-08-16

When a supermassive black hole at the centre of a galaxy accretes matter, it gives rise to a highly energetic phenomenon: an active galactic nucleus. Numerous physical processes have been proposed to account for the funnelling of gas towards the galactic centre to feed the black hole. There are also several physical processes that can remove gas from a galaxy, one of which is ram-pressure stripping by the hot gas that fills the space between galaxies in galaxy clusters. Here we report that six out of a sample of seven 'jellyfish' galaxies-galaxies with long 'tentacles' of material that extend for dozens of kiloparsecs beyond the galactic disks-host an active nucleus, and two of them also have galactic-scale ionization cones. The high incidence of nuclear activity among heavily stripped jellyfish galaxies may be due to ram pressure causing gas to flow towards the centre and triggering the activity, or to an enhancement of the stripping caused by energy injection from the active nucleus, or both. Our analysis of the galactic position and velocity relative to the cluster strongly supports the first hypothesis, and puts forward ram pressure as another possible mechanism for feeding the central supermassive black hole with gas.

Ram-pressure feeding of supermassive black holes

NASA Astrophysics Data System (ADS)

Poggianti, Bianca M.; Jaffé, Yara L.; Moretti, Alessia; Gullieuszik, Marco; Radovich, Mario; Tonnesen, Stephanie; Fritz, Jacopo; Bettoni, Daniela; Vulcani, Benedetta; Fasano, Giovanni; Bellhouse, Callum; Hau, George; Omizzolo, Alessandro

2017-08-01

When a supermassive black hole at the centre of a galaxy accretes matter, it gives rise to a highly energetic phenomenon: an active galactic nucleus. Numerous physical processes have been proposed to account for the funnelling of gas towards the galactic centre to feed the black hole. There are also several physical processes that can remove gas from a galaxy, one of which is ram-pressure stripping by the hot gas that fills the space between galaxies in galaxy clusters. Here we report that six out of a sample of seven ‘jellyfish’ galaxies—galaxies with long ‘tentacles’ of material that extend for dozens of kiloparsecs beyond the galactic disks—host an active nucleus, and two of them also have galactic-scale ionization cones. The high incidence of nuclear activity among heavily stripped jellyfish galaxies may be due to ram pressure causing gas to flow towards the centre and triggering the activity, or to an enhancement of the stripping caused by energy injection from the active nucleus, or both. Our analysis of the galactic position and velocity relative to the cluster strongly supports the first hypothesis, and puts forward ram pressure as another possible mechanism for feeding the central supermassive black hole with gas.

Toward a Stress Process Model of Children’s Exposure to Physical Family and Community Violence

PubMed Central

Brooks-Gunn, Jeanne

2011-01-01

Theoretically informed models are required to further the comprehensive understanding of children’s ETV. We draw on the stress process paradigm to forward an overall conceptual model of ETV (ETV) in childhood and adolescence. Around this conceptual model, we synthesize research in four dominant areas of the literature which are detailed but often disconnected including: (1) exposure to three forms of physical violence (e.g., child physical maltreatment, interparental violence, and community ETV); (2) the multilevel correlates and causes of ETV (e.g., neighborhood characteristics including concentrated disadvantage; family characteristics including socio-economic status and family stressors); (3) a range of consequences of ETV (e.g., internalizing and externalizing mental health problems, role transitions, and academic outcomes); and (4) multilevel and cross domain mediators and moderators of ETV influences (e.g., school and community factors, family social support, and individual coping resources). We highlight the range of interconnected processes through which violence exposures may influence children and suggest opportunities for prevention and intervention. We further identify needed future research on children’s ETV including coping resources as well as research on cumulative contributions of violence exposure, violence exposure modifications, curvilinearity, and timing of exposure. PMID:19434492

Associations of Walking Speed, Grip Strength, and Standing Balance With Total and Cause-Specific Mortality in a General Population of Japanese Elders.

PubMed

Nofuji, Yu; Shinkai, Shoji; Taniguchi, Yu; Amano, Hidenori; Nishi, Mariko; Murayama, Hiroshi; Fujiwara, Yoshinori; Suzuki, Takao

2016-02-01

Walking speed, grip strength, and standing balance are key components of physical performance in older people. The present study aimed to evaluate (1) associations of these physical performance measures with cause-specific mortality, (2) independent associations of individual physical performance measures with mortality, and (3) the added value of combined use of the 3 physical performance measures in predicting all-cause and cause-specific mortality. Prospective cohort study with a follow-up of 10.5 years. Tokyo Metropolitan Institute of Gerontology Longitudinal Interdisciplinary Study on Aging (TMIG-LISA), Japan. A total of 1085 initially nondisabled older Japanese aged 65 to 89 years. Usual walking speed, grip strength, and standing balance were measured at baseline survey. During follow-up, 324 deaths occurred (122 of cardiovascular disease, 75 of cancer, 115 of other causes, and 12 of unknown causes). All 3 physical performance measures were significantly associated with all-cause, cardiovascular, and other-cause mortality, but not with cancer mortality, independent of potential confounders. When all 3 physical performance measures were simultaneously entered into the model, each was significantly independently associated with all-cause and cardiovascular mortality. The C statistics for all-cause and cardiovascular mortality were significantly increased by adding grip strength and standing balance to walking speed (P < .01), and the net reclassification improvement for them was estimated at 18.7% and 7.5%, respectively. Slow walking speed, weak grip strength, and poor standing balance predicted all-cause, cardiovascular, and other-cause mortality, but not cancer mortality, independent of covariates. Moreover, these 3 components of physical performance were independently associated with all-cause and cardiovascular mortality and their combined use increased prognostic power. Copyright © 2016 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

The Hazard Analysis and Critical Control Points (HACCP) generic model for the production of Thai fermented pork sausage (Nham).

PubMed

Paukatong, K V; Kunawasen, S

2001-01-01

Nham is a traditional Thai fermented pork sausage. The major ingredients of Nham are ground pork meat and shredded pork rind. Nham has been reported to be contaminated with Salmonella spp., Staphylococcus aureus, and Listeria monocytogenes. Therefore, it is a potential cause of foodborne diseases for consumers. A Hazard Analysis and Critical Control Points (HACCP) generic model has been developed for the Nham process. Nham processing plants were observed and a generic flow diagram of Nham processes was constructed. Hazard analysis was then conducted. Other than microbial hazards, the pathogens previously found in Nham, sodium nitrite and metal were identified as chemical and physical hazards in this product, respectively. Four steps in the Nham process have been identified as critical control points. These steps are the weighing of the nitrite compound, stuffing, fermentation, and labeling. The chemical hazard of nitrite must be controlled during the weighing step. The critical limit of nitrite levels in the Nham mixture has been set at 100-200 ppm. This level is high enough to control Clostridium botulinum but does not cause chemical hazards to the consumer. The physical hazard from metal clips could be prevented by visual inspection of every Nham product during stuffing. The microbiological hazard in Nham could be reduced in the fermentation process. The critical limit of the pH of Nham was set at lower than 4.6. Since this product is not cooked during processing, finally, educating the consumer, by providing information on the label such as "safe if cooked before consumption", could be an alternative way to prevent the microbiological hazards of this product.

Deviant Peer Affiliation as an Explanatory Mechanism in the Association between Corporal Punishment and Physical Aggression: a Longitudinal Study among Chinese Adolescents.

PubMed

Zhu, Jianjun; Yu, Chengfu; Bao, Zhenzhou; Jiang, Yanping; Zhang, Wei; Chen, Yuanyuan; Qiu, Boyu; Zhang, Jianjun

2017-11-01

Previous research has focused primarily on corporal punishment as a cause and adolescents' physical aggression as an outcome. However, there is a large gap in knowledge of the potentially bidirectional association and explanatory mechanism underlying the association between corporal punishment and physical aggression. The current study, using a longitudinal design across three time points (the fall semester of 7th grade, the fall of 8th grade, and the fall of 9th grade), aimed to a) examine the reciprocal processes between corporal punishment and physical aggression, and b) explore whether deviant peer affiliation may explain such reciprocal connections. Only adolescents participating in all the three time points were included in this study, resulting in a final sample of 342 adolescents (175 boys, 167 girls) who completed questionnaires regarding corporal punishment, deviant peer affiliation, and aggression. Gender, age and socioeconomic status were controlled for in the analyses. Autoregressive cross-lagged models showed that the results did not support the direct reciprocal effect between corporal punishment and physical aggression among Chinese adolescents. A direct longitudinal link from corporal punishment to physical aggression was found, however, the inverse association was not significant. Moreover, regarding the longitudinal underlying process, in one direction, corporal punishment at 7th grade predicted higher levels of deviant peer affiliation at 8th grade. In turn, higher deviant peer affiliation at 8th grade predicted increased physical aggression at 9th grade. At the same time, in the other direction, adolescent physical aggression at 7th grade significantly predicted deviant peer affiliation at 8th grade. In turn, higher deviant peer affiliation at 8th grade predicted decreased corporal punishment at 9th grade. Identifying the direct and underlying reciprocal processes between corporal punishment and adolescent physical aggression has important implications for an integrative framework of theory and prevention.

Evaporative losses from soils covered by physical and different types of biological soil crusts

USGS Publications Warehouse

Chamizo, S.; Cantón, Y.; Domingo, F.; Belnap, J.

2013-01-01

Evaporation of soil moisture is one of the most important processes affecting water availability in semiarid ecosystems. Biological soil crusts, which are widely distributed ground cover in these ecosystems, play a recognized role on water processes. Where they roughen surfaces, water residence time and thus infiltration can be greatly enhanced, whereas their ability to clog soil pores or cap the soil surface when wetted can greatly decrease infiltration rate, thus affecting evaporative losses. In this work, we compared evaporation in soils covered by physical crusts, biological crusts in different developmental stages and in the soils underlying the different biological crust types. Our results show that during the time of the highest evaporation (Day 1), there was no difference among any of the crust types or the soils underlying them. On Day 2, when soil moisture was moderately low (11%), evaporation was slightly higher in well-developed biological soil crusts than in physical or poorly developed biological soil crusts. However, crust removal did not cause significant changes in evaporation compared with the respective soil crust type. These results suggest that the small differences we observed in evaporation among crust types could be caused by differences in the properties of the soil underneath the biological crusts. At low soil moisture (<6%), there was no difference in evaporation among crust types or the underlying soils. Water loss for the complete evaporative cycle (from saturation to dry soil) was similar in both crusted and scraped soils. Therefore, we conclude that for the specific crust and soil types tested, the presence or the type of biological soil crust did not greatly modify evaporation with respect to physical crusts or scraped soils.

Numerical Modeling of Anaerobic Microzones Development in Bulk Oxic Porous Media: An Assessment of Different Microzone Formation Processes

NASA Astrophysics Data System (ADS)

Roy Chowdhury, S.; Zarnetske, J. P.; Briggs, M. A.; Day-Lewis, F. D.; Singha, K.

2017-12-01

Soil and groundwater research indicates that unique biogeochemical "microzones" commonly form within bulk soil masses. The formation of these microzones at the pore-scale has been attributed to a number of causes, including variability of in situ carbon or nutrient sources, intrinsic physical conditions that lead to dual-porosity and mass transfer conditions, or microbial bioclogging of the porous media. Each of these causes, while documented in different porous media systems, potentially can lead to the presence of anaerobic pores residing in a bulk oxic domain. The relative role of these causes operating independently or in conjunction with each other to form microzones is not known. Here, we use a single numerical modeling framework to assess the relative roles of each process in creating anaerobic microzones. Using a two-dimensional pore-network model, coupled with a microbial growth model based on Monod kinetics, simulations were performed to explore the development of these anoxic microzones and their fate under a range of hydrologic, nutrient, and microbial conditions. Initial results parameterized for a stream-groundwater exchange environment (i.e., a hyporheic zone) indicate that external forcing of fluid flux in the domain is a key soil characteristic to anaerobic microzone development as fluid flux governs the nutrient flux. The initial amount of biomass present in the system also plays a major role in the development of the microzones. In terms of dominant in situ causes, the intrinsic physical structure of the local pore space is found to play the key role in development of anaerobic sites by regulating fluxes to reaction sites. Acknowledging and understanding the drivers of these microzones will improve the ability of multiple disciplines to measure and model reactive mass transport in soils and assess if they play a significant role for particular biogeochemical processes and ecosystem functions, such as denitrification and greenhouse gas production.

Associations of objectively assessed physical activity and sedentary time with all-cause mortality in US adults: the NHANES study.

PubMed

Schmid, Daniela; Ricci, Cristian; Leitzmann, Michael F

2015-01-01

Sedentary behavior is related to increased mortality risk. Whether such elevated risk can be offset by enhanced physical activity has not been examined using accelerometry data. We examined the relations of sedentary time and physical activity to mortality from any cause using accelerometry data among 1,677 women and men aged 50 years or older from the National Health and Nutrition Examination Survey (NHANES) 2003-2004 cycle with follow-up through December 31, 2006. During an average follow-up of 34.67 months and 4,845.42 person-years, 112 deaths occurred. In multivariate Cox proportional hazard models, greater sedentary time (≥ median of 8.60 hours/day) was associated with increased risk of mortality from any cause (relative risk (RR) = 2.03; 95% confidence interval (CI) = 1.09-3.81). Low level of moderate to vigorous physical activity (< median of 6.60 minutes/day) was also related to enhanced all-cause mortality risk (RR = 3.30; 95% CI = 1.33-8.17). In combined analyses, greater time spent sedentary and low levels of moderate to vigorous physical activity predicted a substantially elevated all-cause mortality risk. As compared with the combination of a low sedentary level and a high level of moderate to vigorous physical activity, the risks of mortality from all causes were 4.38 (95% CI = 1.26-15.16) for low levels of both sedentary time and physical activity, 2.79 (95% CI = 0.77-10.12) for greater time spent sedentary and high physical activity level, and 7.79 (95% CI = 2.26-26.82) for greater time spent sedentary and low physical activity level. The interaction term between sedentary time and moderate to vigorous physical activity was not statistically significant (p = 0.508). Both high levels of sedentary time and low levels of moderate to vigorous physical activity are strong and independent predictors of early death from any cause. Whether a high physical activity level removes the increased risk of all-cause mortality related to sedentariness requires further investigation.

Associations of Objectively Assessed Physical Activity and Sedentary Time with All-Cause Mortality in US Adults: The NHANES Study

PubMed Central

Schmid, Daniela; Ricci, Cristian; Leitzmann, Michael F.

2015-01-01

Background Sedentary behavior is related to increased mortality risk. Whether such elevated risk can be offset by enhanced physical activity has not been examined using accelerometry data. Materials and Methods We examined the relations of sedentary time and physical activity to mortality from any cause using accelerometry data among 1,677 women and men aged 50 years or older from the National Health and Nutrition Examination Survey (NHANES) 2003–2004 cycle with follow-up through December 31, 2006. Results During an average follow-up of 34.67 months and 4,845.42 person-years, 112 deaths occurred. In multivariate Cox proportional hazard models, greater sedentary time (≥ median of 8.60 hours/day) was associated with increased risk of mortality from any cause (relative risk (RR) = 2.03; 95% confidence interval (CI) = 1.09-3.81). Low level of moderate to vigorous physical activity (< median of 6.60 minutes/day) was also related to enhanced all-cause mortality risk (RR = 3.30; 95% CI = 1.33-8.17). In combined analyses, greater time spent sedentary and low levels of moderate to vigorous physical activity predicted a substantially elevated all-cause mortality risk. As compared with the combination of a low sedentary level and a high level of moderate to vigorous physical activity, the risks of mortality from all causes were 4.38 (95% CI = 1.26-15.16) for low levels of both sedentary time and physical activity, 2.79 (95% CI = 0.77-10.12) for greater time spent sedentary and high physical activity level, and 7.79 (95% CI = 2.26-26.82) for greater time spent sedentary and low physical activity level. The interaction term between sedentary time and moderate to vigorous physical activity was not statistically significant (p = 0.508). Conclusions Both high levels of sedentary time and low levels of moderate to vigorous physical activity are strong and independent predictors of early death from any cause. Whether a high physical activity level removes the increased risk of all-cause mortality related to sedentariness requires further investigation. PMID:25768112

Catalyst activity maintenance study for the liquid phase dimethyl ether process

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

Peng, X.D.; Toseland, B.A.; Underwood, R.P.

1995-12-31

The co-production of dimethyl ether (DME) and methanol from syngas is a process of considerable commercial attractiveness. DME coproduction can double the productivity of a LPMEOH process when using coal-derived syngas. This in itself may offer chemical producers and power companies increased flexibility and more profitable operation. DME is also known as a clean burning liquid fuel; Amoco and Haldor-Topsoe have recently announced the use of DME as an alternative diesel fuel. Moreover, DME can be an interesting intermediate in the production of chemicals such as olefins and vinyl acetate. The current APCl liquid phase dimethyl ether (LPDME) process utilizesmore » a physical mixture of a commercial methanol synthesis catalyst and a dehydration catalyst (e.g., {gamma}-alumina). While this arrangement provides a synergy that results in much higher syngas conversion per pass compared to the methanol-only process, the stability of the catalyst system suffers. The present project is aimed at reducing catalyst deactivation both by understanding the cause(s) of catalyst deactivation and by developing modified catalyst systems. This paper describes the current understanding of the deactivation mechanism.« less

News

NASA Astrophysics Data System (ADS)

2001-05-01

LINKS WITH PRIMARY SCIENCE SAD Physics; PHYSICS RESEARCH In a hurry...; PHYSICS COMMUNITY Scottish Stirling Meeting; PHYSICS AT CONGRESS Global warming forecasts rise in skin cancer; EVENTS 2001 SET week; E-MAIL DISCUSSIONS Learning in science; STUDENT ACTIVITY Paperclip Physics; CURRICULUM DEVELOPMENT Perspectives on Science; AWARDS Award for causing chaos; PHYSICS AT CONGRESS Physics and public heath: Do electrical power lines cause cancer? HIGHER EDUCATION First-year course development; INTERSCHOOL COLLABORATION Monitoring geomagnetic storms; CURRICULUM DEVELOPMENT UK course goes international; PHYSICS IN SCIENCE YEAR Website launched

Influence of Cellulosic Fibres on the Physical Properties of Fibre Cement Composites

NASA Astrophysics Data System (ADS)

Hospodarova, V.; Stevulova, N.; Vaclavik, V.; Dvorsky, T.

2017-10-01

Nowadays, there are new approaches directing to processing of non-conventional fibre-cement composites for application in the housing construction. Vegetable cellulosic fibres coming from natural resources used as reinforcement in cost-effective and environmental friendly building products are in the spotlight. The applying of natural fibres in cement based composites is narrowly linked to the ecological building sector, where a choice of materials is based on components including recyclable, renewable raw materials and low-resource manufacture techniques. In this paper, two types of cellulosic fibres coming from wood pulp and recycled waste paper with 0.2%; 0.3% and 0.5% of fibre addition into cement mixtures were used. Differences in the physical characteristics (flowability, density, coefficient of thermal conductivity and water absorbability) of 28 days hardened fibre-cement composites are investigated. Addition of cellulosic fibres to cement mixture caused worsening the workability of fresh mixture as well as absorbability of hardened composites due to hydrophilic nature of biomaterial, whereas density and thermal conductivity of manufactured cement based fibre plaster are enhanced. The physical properties of cement plasters based on cellulosic fibres depend on structural, physical characteristics of cellulosic fibres, their nature and processing.

Command Disaggregation Attack and Mitigation in Industrial Internet of Things

PubMed Central

Zhu, Pei-Dong; Hu, Yi-Fan; Cui, Peng-Shuai; Zhang, Yan

2017-01-01

A cyber-physical attack in the industrial Internet of Things can cause severe damage to physical system. In this paper, we focus on the command disaggregation attack, wherein attackers modify disaggregated commands by intruding command aggregators like programmable logic controllers, and then maliciously manipulate the physical process. It is necessary to investigate these attacks, analyze their impact on the physical process, and seek effective detection mechanisms. We depict two different types of command disaggregation attack modes: (1) the command sequence is disordered and (2) disaggregated sub-commands are allocated to wrong actuators. We describe three attack models to implement these modes with going undetected by existing detection methods. A novel and effective framework is provided to detect command disaggregation attacks. The framework utilizes the correlations among two-tier command sequences, including commands from the output of central controller and sub-commands from the input of actuators, to detect attacks before disruptions occur. We have designed components of the framework and explain how to mine and use these correlations to detect attacks. We present two case studies to validate different levels of impact from various attack models and the effectiveness of the detection framework. Finally, we discuss how to enhance the detection framework. PMID:29065461

Command Disaggregation Attack and Mitigation in Industrial Internet of Things.

PubMed

Xun, Peng; Zhu, Pei-Dong; Hu, Yi-Fan; Cui, Peng-Shuai; Zhang, Yan

2017-10-21

A cyber-physical attack in the industrial Internet of Things can cause severe damage to physical system. In this paper, we focus on the command disaggregation attack, wherein attackers modify disaggregated commands by intruding command aggregators like programmable logic controllers, and then maliciously manipulate the physical process. It is necessary to investigate these attacks, analyze their impact on the physical process, and seek effective detection mechanisms. We depict two different types of command disaggregation attack modes: (1) the command sequence is disordered and (2) disaggregated sub-commands are allocated to wrong actuators. We describe three attack models to implement these modes with going undetected by existing detection methods. A novel and effective framework is provided to detect command disaggregation attacks. The framework utilizes the correlations among two-tier command sequences, including commands from the output of central controller and sub-commands from the input of actuators, to detect attacks before disruptions occur. We have designed components of the framework and explain how to mine and use these correlations to detect attacks. We present two case studies to validate different levels of impact from various attack models and the effectiveness of the detection framework. Finally, we discuss how to enhance the detection framework.

A volumetric ablation model of EPDM considering complex physicochemical process in porous structure of char layer

NASA Astrophysics Data System (ADS)

Yang, Liu; Xiao-Jing, Yu; Jian-Ming, Ma; Yi-Wen, Guan; Jiang, Li; Qiang, Li; Sa, Yang

2017-06-01

A volumetric ablation model for EPDM (ethylene- propylene-diene monomer) is established in this paper. This model considers the complex physicochemical process in the porous structure of a char layer. An ablation physics model based on a porous structure of a char layer and another model of heterogeneous volumetric ablation char layer physics are then built. In the model, porosity is used to describe the porous structure of a char layer. Gas diffusion and chemical reactions are introduced to the entire porous structure. Through detailed formation analysis, the causes of the compact or loose structure in the char layer and chemical vapor deposition (CVD) reaction between pyrolysis gas and char layer skeleton are introduced. The Arrhenius formula is adopted to determine the methods for calculating carbon deposition rate C which is the consumption rate caused by thermochemical reactions in the char layer, and porosity evolution. The critical porosity value is used as a criterion for char layer porous structure failure under gas flow and particle erosion. This critical porosity value is obtained by fitting experimental parameters and surface porosity of the char layer. Linear ablation and mass ablation rates are confirmed with the critical porosity value. Results of linear ablation and mass ablation rate calculations generally coincide with experimental results, suggesting that the ablation analysis proposed in this paper can accurately reflect practical situations and that the physics and mathematics models built are accurate and reasonable.

Invited perspectives: Hydrological perspectives on precipitation intensity-duration thresholds for landslide initiation: proposing hydro-meteorological thresholds

NASA Astrophysics Data System (ADS)

Bogaard, Thom; Greco, Roberto

2018-01-01

Many shallow landslides and debris flows are precipitation initiated. Therefore, regional landslide hazard assessment is often based on empirically derived precipitation intensity-duration (ID) thresholds and landslide inventories. Generally, two features of precipitation events are plotted and labeled with (shallow) landslide occurrence or non-occurrence. Hereafter, a separation line or zone is drawn, mostly in logarithmic space. The practical background of ID is that often only meteorological information is available when analyzing (non-)occurrence of shallow landslides and, at the same time, it could be that precipitation information is a good proxy for both meteorological trigger and hydrological cause. Although applied in many case studies, this approach suffers from many false positives as well as limited physical process understanding. Some first steps towards a more hydrologically based approach have been proposed in the past, but these efforts received limited follow-up.Therefore, the objective of our paper is to (a) critically analyze the concept of precipitation ID thresholds for shallow landslides and debris flows from a hydro-meteorological point of view and (b) propose a trigger-cause conceptual framework for lumped regional hydro-meteorological hazard assessment based on published examples and associated discussion. We discuss the ID thresholds in relation to return periods of precipitation, soil physics, and slope and catchment water balance. With this paper, we aim to contribute to the development of a stronger conceptual model for regional landslide hazard assessment based on physical process understanding and empirical data.

Ablation dynamics - from absorption to heat accumulation/ultra-fast laser matter interaction

NASA Astrophysics Data System (ADS)

Kramer, Thorsten; Remund, Stefan; Jäggi, Beat; Schmid, Marc; Neuenschwander, Beat

2018-05-01

Ultra-short laser radiation is used in manifold industrial applications today. Although state-of-the-art laser sources are providing an average power of 10-100 W with repetition rates of up to several megahertz, most applications do not benefit from it. On the one hand, the processing speed is limited to some hundred millimeters per second by the dynamics of mechanical axes or galvanometric scanners. On the other hand, high repetition rates require consideration of new physical effects such as heat accumulation and shielding that might reduce the process efficiency. For ablation processes, process efficiency can be expressed by the specific removal rate, ablated volume per time, and average power. The analysis of the specific removal rate for different laser parameters, like average power, repetition rate or pulse duration, and process parameters, like scanning speed or material, can be used to find the best operation point for microprocessing applications. Analytical models and molecular dynamics simulations based on the so-called two-temperature model reveal the causes for the appearance of limiting physical effects. The findings of models and simulations can be used to take advantage and optimize processing strategies.

The effects of thoracic surgery operations on quality of life: a multicenter study.

PubMed

Öz, Gürhan; Solak, Okan; Metin, Muzaffer; Esme, Hıdır; Sayar, Adnan

2015-10-01

Some treatment modalities may cause losses in patients' life comfort because of the treatment process. Our aim is to determine the effects of thoracic surgery operations on patients' quality of life. This is a multicenter and prospective study. A hundred patients, who had undergone posterolateral thoracotomy (PLT) and/or lateral thoracotomy (LT), were included in the study. A quality of life questionnaire (SF-36) was used to determine the changes in life comfort. SF-36 was performed before the operation, on the first month, third month, sixth month and twelfth month after the operation. Seventy-two percent (n = 72) of the patients were male. PLT was performed in 66% (n = 66) of the patients, and LT was performed in 34% (n = 34) of the patients. The types of resections in patients were pneumonectomy in four patients, lobectomy in 59 patients and wedge resection in 11 patients. No resection was performed in 26 patients. Thoracotomy caused deteriorations in physical function (PF), physical role (RP), bodily pain (BP), health, vitality and social function scores. The deteriorations observed in the third month improved in the sixth and twelfth months. The PF, RP, BP and MH scores of the patients with lung resection were much more worsened compared with the patients who did not undergo lung resection. Thoracic surgery operations caused substantial dissatisfaction in life comfort especially in the third month postoperatively. The worsening in physical function, physical role, pain and mental health is much more in patients with resection compared with the patients who did not undergo resection. © 2014 John Wiley & Sons Ltd.

The mechanical microenvironment in cancer: How physics affects tumours.

PubMed

Nagelkerke, Anika; Bussink, Johan; Rowan, Alan E; Span, Paul N

2015-12-01

The tumour microenvironment contributes greatly to the response of tumour cells. It consists of chemical gradients, for example of oxygen and nutrients. However, a physical environment is also present. Apart from chemical input, cells also receive physical signals. Tumours display unique mechanical properties: they are a lot stiffer than normal tissue. This may be either a cause or a consequence of cancer, but literature suggests it has a major impact on tumour cells as will be described in this review. The mechanical microenvironment may cause malignant transformation, possibly through activation of oncogenic pathways and inhibition of tumour suppressor genes. In addition, the mechanical microenvironment may promote tumour progression by influencing processes such as epithelial-to-mesenchymal transition, enhancing cell survival through autophagy, but also affects sensitivity of tumour cells to therapeutics. Furthermore, multiple intracellular signalling pathways prove sensitive to the mechanical properties of the microenvironment. It appears the increased stiffness is unlikely to be caused by increased stiffness of the tumour cells themselves. However, there are indications that tumours display a higher cell density, making them more rigid. In addition, increased matrix deposition in the tumour, as well as increased interstitial fluid pressure may account for the increased stiffness of tumours. Overall, tumour mechanics are significantly different from normal tissue. Therefore, this feature should be further explored for use in cancer prevention, detection and treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaporation and Degradation of a Sessile Droplet of VX on an Impermeable Surface

DTIC Science & Technology

2017-09-01

NOTES 14. ABSTRACT: This report highlights experimental studies into the combined physical and chemical processes that occur when a sessile droplet...resulting chemical change causes a corresponding change in the contact angle and evaporation rate of the sessile droplet on an impermeable surface...for phase separation. 15. SUBJECT TERMS Chemical degradation Phase separation Contact angle 2-(diisopropylamino)ethyl-O-ethyl

Fugitive Dust Emissions: Development of a Real-time Monitor

DTIC Science & Technology

2011-10-01

the mechanical disturbance of soils which injects particles into the air. Common sources of FD include vehicles driving on unpaved roads...agricultural tilling, and heavy construction operations. For these sources the dust-generation process is caused by two basic physical phenomena...visibility, source apportionment , etc. The PM10 standard set by the U.S. Environmental Protection Agency in 1987 is an example of size-selective

Active Control of Engine Dynamics (Le controle actif pour la dynamique des moteurs)

DTIC Science & Technology

2002-11-01

optimum operating conditions, avoiding, for example, inadvertent operation when the pulsations can cause unacceptable rates of surface heat transfer or...such as shipboard incineration, and power and heat generation in the field. Because the practical problem of suppressing combustion instabilities has...aforementioned physical processes are essentially completed prior to entering the combustor. One consequence of fuel-air premixing is that the heat

The Origins of Scintillator Non-Proportionality

NASA Astrophysics Data System (ADS)

Moses, W. W.; Bizarri, G. A.; Williams, R. T.; Payne, S. A.; Vasil'ev, A. N.; Singh, J.; Li, Q.; Grim, J. Q.; Choong, W.-S.

2012-10-01

Recent years have seen significant advances in both theoretically understanding and mathematically modeling the underlying causes of scintillator non-proportionality. The core cause is that the interaction of radiation with matter invariably leads to a non-uniform ionization density in the scintillator, coupled with the fact that the light yield depends on the ionization density. The mechanisms that lead to the luminescence dependence on ionization density are incompletely understood, but several important features have been identified, notably Auger-like processes (where two carriers of excitation interact with each other, causing one to de-excite non-radiatively), the inability of excitation carriers to recombine (caused either by trapping or physical separation), and the carrier mobility. This paper reviews the present understanding of the fundamental origins of scintillator non-proportionality, specifically the various theories that have been used to explain non-proportionality.

When the face says it all: dysmorphology in identifying syndromic causes of epilepsy.

PubMed

Dixit, Abhijit; Suri, Mohnish

2016-04-01

Identifying the underlying cause of epilepsy often helps in choosing the appropriate management, suggests the long-term prognosis and clarifies the risk of the same condition in relatives. Epilepsy has many causes and a small but significant proportion of affected people have an identifiable genetic cause. Here, we discuss the role of genetic testing in adults with epilepsy, focusing on dysmorphic features noticeable on physical examination that might provide a strong clue to a specific genetic syndrome. We give illustrative examples of recognisable facial 'gestalt'. An astute clinician can recognise such clues and significantly shorten the process of making the underlying diagnosis in their patient. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Properties of solid polymer electrolyte fluorocarbon film. [used in hydrogen/oxygen fuel cells

NASA Technical Reports Server (NTRS)

Alston, W. B.

1973-01-01

The ionic fluorocarbon film used as the solid polymer electrolyte in hydrogen/oxygen fuel cells was found to exhibit delamination failures. Polarized light microscopy of as-received film showed a lined region at the center of the film thickness. It is shown that these lines were not caused by incomplete saponification but probably resulted from the film extrusion process. The film lines could be removed by an annealing process. Chemical, physical, and tensile tests showed that annealing improved or sustained the water contents, spectral properties, thermo-oxidative stability, and tensile properties of the film. The resistivity of the film was significantly decreased by the annealing process.

Assessing the Effects of Data Compression in Simulations Using Physically Motivated Metrics

DOE PAGES

Laney, Daniel; Langer, Steven; Weber, Christopher; ...

2014-01-01

This paper examines whether lossy compression can be used effectively in physics simulations as a possible strategy to combat the expected data-movement bottleneck in future high performance computing architectures. We show that, for the codes and simulations we tested, compression levels of 3–5X can be applied without causing significant changes to important physical quantities. Rather than applying signal processing error metrics, we utilize physics-based metrics appropriate for each code to assess the impact of compression. We evaluate three different simulation codes: a Lagrangian shock-hydrodynamics code, an Eulerian higher-order hydrodynamics turbulence modeling code, and an Eulerian coupled laser-plasma interaction code. Wemore » compress relevant quantities after each time-step to approximate the effects of tightly coupled compression and study the compression rates to estimate memory and disk-bandwidth reduction. We find that the error characteristics of compression algorithms must be carefully considered in the context of the underlying physics being modeled.« less

Modeling temporal changes of low-frequency earthquake bursts near Parkfield, CA

NASA Astrophysics Data System (ADS)

Wu, C.; Daub, E. G.

2016-12-01

Tectonic tremor and low-frequency earthquakes (LFE) are found in the deeper crust of various tectonic environments in the last decade. LFEs are presumed to be caused by failure of deep fault patches during a slow slip event, and the long-term variation in LFE recurrence could provide crucial insight into the deep fault zone processes that may lead to future large earthquakes. However, the physical mechanisms causing the temporal changes of LFE recurrence are still under debate. In this study, we combine observations of long-term changes in LFE burst activities near Parkfield, CA with a brittle and ductile friction (BDF) model, and use the model to constrain the possible physical mechanisms causing the observed long-term changes in LFE burst activities after the 2004 M6 Parkfield earthquake. The BDF model mimics the slipping of deep fault patches by a spring-drugged block slider with both brittle and ductile friction components. We use the BDF model to test possible mechanisms including static stress imposed by the Parkfield earthquake, changes in pore pressure, tectonic force, afterslip, brittle friction strength, and brittle contact failure distance. The simulation results suggest that changes in brittle friction strength and failure distance are more likely to cause the observed changes in LFE bursts than other mechanisms.

Transforming community access to space science models

NASA Astrophysics Data System (ADS)

MacNeice, Peter; Hesse, Michael; Kuznetsova, Maria; Maddox, Marlo; Rastaetter, Lutz; Berrios, David; Pulkkinen, Antti

2012-04-01

Researching and forecasting the ever changing space environment (often referred to as space weather) and its influence on humans and their activities are model-intensive disciplines. This is true because the physical processes involved are complex, but, in contrast to terrestrial weather, the supporting observations are typically sparse. Models play a vital role in establishing a physically meaningful context for interpreting limited observations, testing theory, and producing both nowcasts and forecasts. For example, with accurate forecasting of hazardous space weather conditions, spacecraft operators can place sensitive systems in safe modes, and power utilities can protect critical network components from damage caused by large currents induced in transmission lines by geomagnetic storms.

Transforming Community Access to Space Science Models

NASA Technical Reports Server (NTRS)

MacNeice, Peter; Heese, Michael; Kunetsova, Maria; Maddox, Marlo; Rastaetter, Lutz; Berrios, David; Pulkkinen, Antti

2012-01-01

Researching and forecasting the ever changing space environment (often referred to as space weather) and its influence on humans and their activities are model-intensive disciplines. This is true because the physical processes involved are complex, but, in contrast to terrestrial weather, the supporting observations are typically sparse. Models play a vital role in establishing a physically meaningful context for interpreting limited observations, testing theory, and producing both nowcasts and forecasts. For example, with accurate forecasting of hazardous space weather conditions, spacecraft operators can place sensitive systems in safe modes, and power utilities can protect critical network components from damage caused by large currents induced in transmission lines by geomagnetic storms.

Computational Thermomechanical Modelling of Early-Age Silicate Composites

NASA Astrophysics Data System (ADS)

Vala, J.; Št'astník, S.; Kozák, V.

2009-09-01

Strains and stresses in early-age silicate composites, widely used in civil engineering, especially in fresh concrete mixtures, in addition to those caused by exterior mechanical loads, are results of complicated non-deterministic physical and chemical processes. Their numerical prediction at the macro-scale level requires the non-trivial physical analysis based on the thermodynamic principles, making use of micro-structural information from both theoretical and experimental research. The paper introduces a computational model, based on a nonlinear system of macroscopic equations of evolution, supplied with certain effective material characteristics, coming from the micro-scale analysis, and sketches the algorithm for its numerical analysis.

[Health policy interventions: the pathway to public health].

PubMed

Andersen, Karl; Gudnason, Vilmundur

2013-03-01

Chronic non-communicable diseases (NCDs) are currently the main cause of premature death and disability in the world. Most of these NCDs are due to unhealthy lifestyle choices i.e. tobacco, unhealthy diet, lack of physical exercise and alcohol consumption. Studies have shown that health policy interventions aiming at improving diet and physical activity and reducing tobacco consumption are inexpensive, effective and cost saving. In this paper we address the political health policy interventions that have been shown to improve public health. We discuss some of the theories of behavioral economics which explain the processes involved in our every-day choices regarding lifestyle and diet.

25 CFR 224.138 - What must the Director do if a tribe's noncompliance has caused imminent jeopardy to a physical...

Code of Federal Regulations, 2010 CFR

2010-04-01

... caused imminent jeopardy to a physical trust asset? 224.138 Section 224.138 Indians BUREAU OF INDIAN... TRIBAL ENERGY DEVELOPMENT AND SELF DETERMINATION ACT Periodic Reviews Noncompliance § 224.138 What must the Director do if a tribe's noncompliance has caused imminent jeopardy to a physical trust asset? If...

The effects of smoking and physical inactivity on advancing mortality in U.S. adults.

PubMed

Borrell, Luisa N

2014-06-01

The aim of the study was to calculate the rate advancement period (RAP) by which deaths for all-cause and cardiovascular disease (CVD)-specific mortality is advanced by smoking and physical inactivity among U.S. adults aged 18 years or more who participated in the Third National Health and Nutrition Examination Survey and were followed to December 31, 2006. Mortality status was determined using the underlying cause of death. Cox regression was used to calculate the advanced time of deaths for all-cause and CVD-specific mortality among exposed adults relative to their nonexposed counterparts. Deaths for all-cause and CVD-specific mortality were advanced by 7.9 and 5.1 years among current smoker adults. For physically inactive adults, the RAPs for all-cause and CVD-specific mortality were 4.0 and 2.4 years, respectively. The joint effects of current smoking, physical inactivity, and obesity resulted in early all-cause and CVD-specific deaths of 14.2 and 12.2 years. For current smokers, physically inactive, and overweight adults, the RAPs for all-cause and CVD-specific deaths were 7.9 and 8.9 years, respectively. Our findings suggest that smoking and physical inactivity could significantly advance the time of death associated with all-cause and CVD-specific mortality by at least 2.4 years among U.S. adults. Moreover, the advancement death period for the joint effects of smoking, physical inactivity, and overweight or obesity could be at least 7.9 years. Copyright © 2014 Elsevier Inc. All rights reserved.

Coastal vulnerability assessment of Puducherry coast, India using analytical hierarchical process

NASA Astrophysics Data System (ADS)

Mani Murali, R.; Ankita, M.; Amrita, S.; Vethamony, P.

2013-03-01

Increased frequency of natural hazards such as storm surge, tsunami and cyclone, as a consequence of change in global climate, is predicted to have dramatic effects on the coastal communities and ecosystems by virtue of the devastation they cause during and after their occurrence. The tsunami of December 2004 and the Thane cyclone of 2011 caused extensive human and economic losses along the coastline of Puducherry and Tamil Nadu. The devastation caused by these events highlighted the need for vulnerability assessment to ensure better understanding of the elements causing different hazards and to consequently minimize the after-effects of the future events. This paper advocates an Analytical Hierarchical Process (AHP) based approach to coastal vulnerability studies as an improvement to the existing methodologies for vulnerability assessment. The paper also encourages the inclusion of socio-economic parameters along with the physical parameters to calculate the coastal vulnerability index using AHP derived weights. Seven physical-geological parameters (slope, geomorphology, elevation, shoreline change, sea level rise, significant wave height and tidal range) and four socio-economic factors (population, Land-use/Land-cover (LU/LC), roads and location of tourist places) are considered to measure the Physical Vulnerability Index (PVI) as well as the Socio-economic Vulnerability Index (SVI) of the Puducherry coast. Based on the weights and scores derived using AHP, vulnerability maps are prepared to demarcate areas with very low, medium and high vulnerability. A combination of PVI and SVI values are further utilized to compute the Coastal Vulnerability Index (CVI). Finally, the various coastal segments are grouped into the 3 vulnerability classes to obtain the final coastal vulnerability map. The entire coastal extent between Muthiapet and Kirumampakkam as well as the northern part of Kalapet is designated as the high vulnerability zone which constitutes 50% of the coastline. The region between the southern coastal extent of Kalapet and Lawspet is the medium vulnerability zone and the rest 25% is the low vulnerability zone. The results obtained, enable to identify and prioritize the more vulnerable areas of the region to further assist the government and the residing coastal communities in better coastal management and conservation.

Coastal vulnerability assessment of Puducherry coast, India, using the analytical hierarchical process

NASA Astrophysics Data System (ADS)

Mani Murali, R.; Ankita, M.; Amrita, S.; Vethamony, P.

2013-12-01

As a consequence of change in global climate, an increased frequency of natural hazards such as storm surges, tsunamis and cyclones, is predicted to have dramatic affects on the coastal communities and ecosystems by virtue of the devastation they cause during and after their occurrence. The tsunami of December 2004 and the Thane cyclone of 2011 caused extensive human and economic losses along the coastline of Puducherry and Tamil Nadu. The devastation caused by these events highlighted the need for vulnerability assessment to ensure better understanding of the elements causing different hazards and to consequently minimize the after- effects of the future events. This paper demonstrates an analytical hierarchical process (AHP)-based approach to coastal vulnerability studies as an improvement to the existing methodologies for vulnerability assessment. The paper also encourages the inclusion of socio-economic parameters along with the physical parameters to calculate the coastal vulnerability index using AHP-derived weights. Seven physical-geological parameters (slope, geomorphology, elevation, shoreline change, sea level rise, significant wave height and tidal range) and four socio-economic factors (population, land use/land cover (LU/LC), roads and location of tourist areas) are considered to measure the physical vulnerability index (PVI) as well as the socio-economic vulnerability index (SVI) of the Puducherry coast. Based on the weights and scores derived using AHP, vulnerability maps are prepared to demarcate areas with very low, medium and high vulnerability. A combination of PVI and SVI values are further utilized to compute the coastal vulnerability index (CVI). Finally, the various coastal segments are grouped into the 3 vulnerability classes to obtain the coastal vulnerability map. The entire coastal extent between Muthiapet and Kirumampakkam as well as the northern part of Kalapet is designated as the high vulnerability zone, which constitutes 50% of the coastline. The region between the southern coastal extent of Kalapet and Lawspet is the medium vulnerability zone and the remaining 25% is the low vulnerability zone. The results obtained enable the identification and prioritization of the more vulnerable areas of the region in order to further assist the government and the residing coastal communities in better coastal management and conservation.

Quantitative Simulation of QARBM Challenge Events During Radiation Belt Enhancements

NASA Astrophysics Data System (ADS)

Li, W.; Ma, Q.; Thorne, R. M.; Bortnik, J.; Chu, X.

2017-12-01

Various physical processes are known to affect energetic electron dynamics in the Earth's radiation belts, but their quantitative effects at different times and locations in space need further investigation. This presentation focuses on discussing the quantitative roles of various physical processes that affect Earth's radiation belt electron dynamics during radiation belt enhancement challenge events (storm-time vs. non-storm-time) selected by the GEM Quantitative Assessment of Radiation Belt Modeling (QARBM) focus group. We construct realistic global distributions of whistler-mode chorus waves, adopt various versions of radial diffusion models (statistical and event-specific), and use the global evolution of other potentially important plasma waves including plasmaspheric hiss, magnetosonic waves, and electromagnetic ion cyclotron waves from all available multi-satellite measurements. These state-of-the-art wave properties and distributions on a global scale are used to calculate diffusion coefficients, that are then adopted as inputs to simulate the dynamical electron evolution using a 3D diffusion simulation during the storm-time and the non-storm-time acceleration events respectively. We explore the similarities and differences in the dominant physical processes that cause radiation belt electron dynamics during the storm-time and non-storm-time acceleration events. The quantitative role of each physical process is determined by comparing against the Van Allen Probes electron observations at different energies, pitch angles, and L-MLT regions. This quantitative comparison further indicates instances when quasilinear theory is sufficient to explain the observed electron dynamics or when nonlinear interaction is required to reproduce the energetic electron evolution observed by the Van Allen Probes.

Visualizing the response of a gut bacterial population to antibiotic perturbations

NASA Astrophysics Data System (ADS)

Schlomann, Brandon; Wiles, Travis; Guillemin, Karen; Parthasarathy, Raghuveer

Each of our intestines is home to a vast ecosystem composed of trillions of bacteria in a dynamic environment. Bacterial communities face fluctuations in nutrient influx, invasions by new microbes, physical disturbances from peristalsis, and, perhaps, the arrival of antibiotic drugs. Metagenomic profiling has shown that antibiotic treatments can cause major changes in the composition of species present in the gut, at timescales shorter than a day. How this happens is unknown, as these dynamics have never been observed directly. I'll present recent work that addresses this by using well-defined microbial communities in a model organism, the zebrafish. Light Sheet Fluorescence Microscopy is used to image a commensal species of Vibrioresponding to antibiotic perturbations in the guts of live, larval fish. We find that sub-lethal concentrations of different classes of antibiotics induce similar physical responses in Vibrio, namely filamentation and reduction of motility. The arrested bacteria then aggregate and can be ejected via peristalsis, resulting in large population collapses. These observations suggest that antibiotics can cause large disruptions to gut ecosystems even in low concentrations, and that physical processes may be important drivers of response dynamics.

Domestic violence against women: a qualitative study in a rural community.

PubMed

Kaur, Ravneet; Garg, Suneela

2010-04-01

Domestic violence is a major contributor to physical and mental ill health of women and is evident, to some degree, in every society in the world. The World Health Organization reports that globally 29% to 62% of women have experienced physical or sexual violence by an intimate partner. Ending gender discrimination and all forms of violence against women requires an understanding of the prevailing culture of bias and violence. The present study was conducted in a rural area in India. Focus group discussions (FGDs) were conducted among married women in the age group of 18 to 35 years. Physical violence was a major cause of concern among these women. Some women had to suffer even during pregnancy. An alcoholic husband emerged as the main cause for domestic violence. Husbands' relatives instigating wife beating was also common. Majority of the women preferred to remain silent despite being victimized. The women feared to resort to law because of implications such as social isolation. To address this, all sectors including education, health, legal, and judicial must work in liaison. Gender inequality must be eliminated and equal participation of women in the decision-making and development processes must be ensured.

Vulnerability of water supply systems to cyber-physical attacks

NASA Astrophysics Data System (ADS)

Galelli, Stefano; Taormina, Riccardo; Tippenhauer, Nils; Salomons, Elad; Ostfeld, Avi

2016-04-01

The adoption of smart meters, distributed sensor networks and industrial control systems has largely improved the level of service provided by modern water supply systems. Yet, the progressive computerization exposes these critical infrastructures to cyber-physical attacks, which are generally aimed at stealing critical information (cyber-espionage) or causing service disruption (denial-of-service). Recent statistics show that water and power utilities are undergoing frequent attacks - such as the December power outage in Ukraine - , attracting the interest of operators and security agencies. Taking the security of Water Distribution Networks (WDNs) as domain of study, our work seeks to characterize the vulnerability of WDNs to cyber-physical attacks, so as to conceive adequate defense mechanisms. We extend the functionality of EPANET, which models hydraulic and water quality processes in pressurized pipe networks, to include a cyber layer vulnerable to repeated attacks. Simulation results on a medium-scale network show that several hydraulic actuators (valves and pumps, for example) can be easily attacked, causing both service disruption - i.e., water spillage and loss of pressure - and structural damages - e.g., pipes burst. Our work highlights the need for adequate countermeasures, such as attacks detection and reactive control systems.

Experimental modelling of fragmentation applied to volcanic explosions

NASA Astrophysics Data System (ADS)

Haug, Øystein Thordén; Galland, Olivier; Gisler, Galen R.

2013-12-01

Explosions during volcanic eruptions cause fragmentation of magma and host rock, resulting in fragments with sizes ranging from boulders to fine ash. The products can be described by fragment size distributions (FSD), which commonly follow power laws with exponent D. The processes that lead to power-law distributions and the physical parameters that control D remain unknown. We developed a quantitative experimental procedure to study the physics of the fragmentation process through time. The apparatus consists of a Hele-Shaw cell containing a layer of cohesive silica flour that is fragmented by a rapid injection of pressurized air. The evolving fragmentation of the flour is monitored with a high-speed camera, and the images are analysed to obtain the evolution of the number of fragments (N), their average size (A), and the FSD. Using the results from our image-analysis procedure, we find transient empirical laws for N, A and the exponent D of the power-law FSD as functions of the initial air pressure. We show that our experimental procedure is a promising tool for unravelling the complex physics of fragmentation during phreatomagmatic and phreatic eruptions.

Standard cell electrical and physical variability analysis based on automatic physical measurement for design-for-manufacturing purposes

NASA Astrophysics Data System (ADS)

Shauly, Eitan; Parag, Allon; Khmaisy, Hafez; Krispil, Uri; Adan, Ofer; Levi, Shimon; Latinski, Sergey; Schwarzband, Ishai; Rotstein, Israel

2011-04-01

A fully automated system for process variability analysis of high density standard cell was developed. The system consists of layout analysis with device mapping: device type, location, configuration and more. The mapping step was created by a simple DRC run-set. This database was then used as an input for choosing locations for SEM images and for specific layout parameter extraction, used by SPICE simulation. This method was used to analyze large arrays of standard cell blocks, manufactured using Tower TS013LV (Low Voltage for high-speed applications) Platforms. Variability of different physical parameters like and like Lgate, Line-width-roughness and more as well as of electrical parameters like drive current (Ion), off current (Ioff) were calculated and statistically analyzed, in order to understand the variability root cause. Comparison between transistors having the same W/L but with different layout configurations and different layout environments (around the transistor) was made in terms of performances as well as process variability. We successfully defined "robust" and "less-robust" transistors configurations, and updated guidelines for Design-for-Manufacturing (DfM).

Outdoor thermal comfort and behaviour in urban area

NASA Astrophysics Data System (ADS)

Inavonna, I.; Hardiman, G.; Purnomo, A. B.

2018-01-01

Outdoor comfort is important due to the public spaces functions. Open spaces provide thermal comfort and a pleasant experience to improve the city life quality effectively. The influence of thermal comfort in outdoor activities is a complex problem. This paper presents a literature review and discussion of aspects of physical, psychology, and social behaviour toward outdoor thermal comfort. The valuation is determined not only by the “physical state” but also by the “state of mind”. The assessment is static and objective (i.e., physical and physiological characteristics) that it should be measured. Furthermore, an effective model to provide the knowledge of climatic conditions, as well as the dynamic and subjective aspects (i.e., psychological and social characteristics and behaviour), requires a comprehensive interview and observation. The model will be examined to describe the behaviour that is a reflection of perception and behaviour toward the environment. The adaptation process will constantly evolve so that it becomes a continuous cause between human behaviour and the spatial setting of the formation, which is eventually known as places and not just spaces. This evolutionary process is a civic art form.

Physical bases of the generation of short-term earthquake precursors: A complex model of ionization-induced geophysical processes in the lithosphere-atmosphere-ionosphere-magnetosphere system

NASA Astrophysics Data System (ADS)

Pulinets, S. A.; Ouzounov, D. P.; Karelin, A. V.; Davidenko, D. V.

2015-07-01

This paper describes the current understanding of the interaction between geospheres from a complex set of physical and chemical processes under the influence of ionization. The sources of ionization involve the Earth's natural radioactivity and its intensification before earthquakes in seismically active regions, anthropogenic radioactivity caused by nuclear weapon testing and accidents in nuclear power plants and radioactive waste storage, the impact of galactic and solar cosmic rays, and active geophysical experiments using artificial ionization equipment. This approach treats the environment as an open complex system with dissipation, where inherent processes can be considered in the framework of the synergistic approach. We demonstrate the synergy between the evolution of thermal and electromagnetic anomalies in the Earth's atmosphere, ionosphere, and magnetosphere. This makes it possible to determine the direction of the interaction process, which is especially important in applications related to short-term earthquake prediction. That is why the emphasis in this study is on the processes proceeding the final stage of earthquake preparation; the effects of other ionization sources are used to demonstrate that the model is versatile and broadly applicable in geophysics.

High-resolution modeling of a marine ecosystem using the FRESCO hydroecological model

NASA Astrophysics Data System (ADS)

Zalesny, V. B.; Tamsalu, R.

2009-02-01

The FRESCO (Finnish Russian Estonian Cooperation) mathematical model describing a marine hydroecosystem is presented. The methodology of the numerical solution is based on the method of multicomponent splitting into physical and biological processes, spatial coordinates, etc. The model is used for the reproduction of physical and biological processes proceeding in the Baltic Sea. Numerical experiments are performed with different spatial resolutions for four marine basins that are enclosed into one another: the Baltic Sea, the Gulf of Finland, the Tallinn-Helsinki water area, and Tallinn Bay. Physical processes are described by the equations of nonhydrostatic dynamics, including the k-ω parametrization of turbulence. Biological processes are described by the three-dimensional equations of an aquatic ecosystem with the use of a size-dependent parametrization of biochemical reactions. The main goal of this study is to illustrate the efficiency of the developed numerical technique and to demonstrate the importance of a high spatial resolution for water basins that have complex bottom topography, such as the Baltic Sea. Detailed information about the atmospheric forcing, bottom topography, and coastline is very important for the description of coastal dynamics and specific features of a marine ecosystem. Experiments show that the spatial inhomogeneity of hydroecosystem fields is caused by the combined effect of upwelling, turbulent mixing, surface-wave breaking, and temperature variations, which affect biochemical reactions.

The effect of processing on the surface physical stability of amorphous solid dispersions.

PubMed

Yang, Ziyi; Nollenberger, Kathrin; Albers, Jessica; Moffat, Jonathan; Craig, Duncan; Qi, Sheng

2014-11-01

The focus of this study was to investigate the effect of processing on the surface crystallization of amorphous molecular dispersions and gain insight into the mechanisms underpinning this effect. The model systems, amorphous molecular dispersions of felodipine-EUDRAGIT® E PO, were processed both using spin coating (an ultra-fast solvent evaporation based method) and hot melt extrusion (HME) (a melting based method). Amorphous solid dispersions with drug loadings of 10-90% (w/w) were obtained by both processing methods. Samples were stored under 75% RH/room temperatures for up to 10months. Surface crystallization was observed shortly after preparation for the HME samples with high drug loadings (50-90%). Surface crystallization was characterized by powder X-ray diffraction (PXRD), ATR-FTIR spectroscopy and imaging techniques (SEM, AFM and localized thermal analysis). Spin coated molecular dispersions showed significantly higher surface physical stability than hot melt extruded samples. For both systems, the progress of the surface crystal growth followed zero order kinetics on aging. Drug enrichment at the surfaces of HME samples on aging was observed, which may contribute to surface crystallization of amorphous molecular dispersions. In conclusion it was found the amorphous molecular dispersions prepared by spin coating had a significantly higher surface physical stability than the corresponding HME samples, which may be attributed to the increased process-related apparent drug-polymer solubility and reduced molecular mobility due to the quenching effect caused by the rapid solvent evaporation in spin coating. Copyright © 2014 Elsevier B.V. All rights reserved.

Theory and Modeling of Liquid Explosive Detonation

NASA Astrophysics Data System (ADS)

Tarver, Craig M.; Urtiew, Paul A.

2010-10-01

The current understanding of the detonation reaction zones of liquid explosives is discussed in this article. The physical and chemical processes that precede and follow exothermic chemical reaction within the detonation reaction zone are discussed within the framework of the nonequilibrium Zeldovich-von Neumann-Doring (NEZND) theory of self-sustaining detonation. Nonequilibrium chemical and physical processes cause finite time duration induction zones before exothermic chemical energy release occurs. This separation between the leading shock wave front and the chemical energy release needed to sustain it results in shock wave amplification and the subsequent formation of complex three-dimensional cellular structures in all liquid detonation waves. To develop a practical Zeldovich-von Neumann-Doring (ZND) reactive flow model for liquid detonation, experimental data on reaction zone structure, confined failure diameter, unconfined failure diameter, and failure wave velocity in the Dremin-Trofimov test for detonating nitromethane are calculated using the ignition and growth reactive flow model.

Performance profiling for brachytherapy applications

NASA Astrophysics Data System (ADS)

Choi, Wonqook; Cho, Kihyeon; Yeo, Insung

2018-05-01

In many physics applications, a significant amount of software (e.g. R, ROOT and Geant4) is developed on novel computing architectures, and much effort is expended to ensure the software is efficient in terms of central processing unit (CPU) time and memory usage. Profiling tools are used during the evaluation process to evaluate the efficiency; however, few such tools are able to accommodate low-energy physics regions. To address this limitation, we developed a low-energy physics profiling system in Geant4 to profile the CPU time and memory of software applications in brachytherapy applications. This paper describes and evaluates specific models that are applied to brachytherapy applications in Geant4, such as QGSP_BIC_LIV, QGSP_BIC_EMZ, and QGSP_BIC_EMY. The physics range in this tool allows it to be used to generate low energy profiles in brachytherapy applications. This was a limitation in previous studies, which caused us to develop a new profiling tool that supports profiling in the MeV range, in contrast to the TeV range that is supported by existing high-energy profiling tools. In order to easily compare the profiling results between low-energy and high-energy modes, we employed the same software architecture as that in the SimpliCarlo tool developed at the Fermilab National Accelerator Laboratory (FNAL) for the Large Hadron Collider (LHC). The results show that the newly developed profiling system for low-energy physics (less than MeV) complements the current profiling system used for high-energy physics (greater than TeV) applications.

Magnetosphere-Ionosphere Coupling in the Auroral Zone

NASA Technical Reports Server (NTRS)

Schriver, David

2004-01-01

The visual light display at high latitudes referred to as the aurora fascinates casual observers and researchers alike. The natural question is what causes the aurora? We know that energized electrons streaming along the Earth's ambient magnetic field and colliding with atmospheric particles produce aurora. We do not know for certain, however, how these electrons are accelerated to high energies primarily in the field-aligned direction toward the Earth, or what the drivers of this acceleration are. As such, the goal of this Guest Investigator research project was to examine the physical processes that can cause field-aligned acceleration of plasma particles in the auroral region.

Vapor Flow Patterns During a Start-Up Transient in Heat Pipes

NASA Technical Reports Server (NTRS)

Issacci, F.; Ghoniem, N, M.; Catton, I.

1996-01-01

The vapor flow patterns in heat pipes are examined during the start-up transient phase. The vapor core is modelled as a channel flow using a two dimensional compressible flow model. A nonlinear filtering technique is used as a post process to eliminate the non-physical oscillations of the flow variables. For high-input heat flux, multiple shock reflections are observed in the evaporation region. The reflections cause a reverse flow in the evaporation and circulations in the adiabatic region. Furthermore, each shock reflection causes a significant increase in the local pressure and a large pressure drop along the heat pipe.

[In Process Citation].

PubMed

Scherrer, Beat; Della Chiesa, Andrea; Polska, Elzbieta; Kutten Berger, Johannes J

Inflammation of bone is caused either by bacterial infection or occasionally by physical stimulus. Primary chronic osteomyelitis of mandibular bone is a chronic inflammation of an unknown cause. Pain, swelling, limited mouth opening, regional lymphadenopathy and hypaesthesia are clinical symptoms at initial presentation. Results of biopsy, computed tomography and scintigraphy reveal the diagnosis of a primary chronic osteomyelitis. Its management is long-term antibiotic therapy, hyperbaric oxygen and surgical therapy, even bisphophonate treatement may be a good option. The case report presents a primary progressive chronic osteomyelitis of the manibular bone of a ten year old boy. Clinical and radiological signs are discussed as well as diagnosis, management and follow-up.

Impact of persistence and non-persistence in leisure time physical activity on coronary heart disease and all-cause mortality: The Copenhagen City Heart Study.

PubMed

Schnohr, Peter; O'Keefe, James H; Lange, Peter; Jensen, Gorm Boje; Marott, Jacob Louis

2017-10-01

Aims The aim of this study was to investigate the impact of persistence and non-persistence in leisure time physical activity on coronary heart disease and all-cause mortality. Methods and results In the Copenhagen City Heart Study, we prospectively followed 12,314 healthy subjects for 33 years of maximum follow-up with at least two repeated measures of physical activity. The association between persistence and non-persistence in leisure time physical activity, coronary heart disease and all-cause mortality were assessed by multivariable Cox regression analyses. Coronary heart disease mortality for persistent physical activity in leisure compared to persistent sedentary activity were: light hazard ratio (HR) 0.76; 95% confidence interval (CI) 0.63-0.92, moderate HR 0.52; 95% CI 0.41-0.67, and high physical activity HR 0.51; 95% CI, 0.30-0.88. The differences in longevity were 2.8 years for light, 4.5 years for moderate and 5.5 years for high physical activity. A substantial increase in physical activity was associated with lower coronary heart disease mortality (HR 0.75; 95% CI 0.52-1.08) corresponding to 2.4 years longer life, whereas a substantial decrease in physical activity was associated with higher coronary heart disease mortality (HR 1.61; 95% CI 1.11-2.33) corresponding to 4.2 years shorter life than the unchanged group. A similar pattern was observed for all-cause mortality. Conclusion We found inverse dose-response relationships between persistent leisure time physical activity and both coronary heart disease and all-cause mortality. A substantial increase in physical activity was associated with a significant gain in longevity, whereas a decrease in physical activity was associated with even greater loss of longevity.

Treating the insomniac patient - General measures and psychological and pharmacological treatment

NASA Technical Reports Server (NTRS)

Kales, A.; Bixler, E. O.; Kales, J. D.

1975-01-01

The general preliminary measures for treating insomnia include moderate physical exercise several hours before bedtime, and the relaxation of complex mental activity before bedtime. A case history concerning a woman with marital troubles is offered as evidence that insomnia may be caused by deeply rooted psychological and situational problems. Another case history illustrates how prior pharmacological treatment may complicate the process of clinically evaluating an insomniac.

Biologically-Oriented Processes in the Coastal Sea Ice Zone of the White Sea

NASA Astrophysics Data System (ADS)

Melnikov, I. A.

2002-12-01

The annual advance and retreat of sea ice is a major physical determinant of spatial and temporal changes in the structure and function of marine coastal biological communities. Sea ice biological data obtained in the tidal zone of Kandalaksha Gulf (White Sea) during 1996-2001 period will be presented. Previous observations in this area were mainly conducted during the ice-free summer season. However, there is little information on the ice-covered winter season (6-7 months duration), and, especially, on the sea-ice biology in the coastal zone within tidal regimes. During the January-May period time-series observations were conducted on transects along shorelines with coastal and fast ice. Trends in the annual extent of sea ice showed significant impacts on ice-associated biological communities. Three types of sea ice impact on kelps, balanoides, littorinas and amphipods are distinguished: (i) positive, when sea ice protects these populations from grinding (ii) negative, when ice grinds both fauna and flora, and (iii) a combined effect, when fast ice protects, but anchored ice grinds plant and animals. To understand the full spectrum of ecological problems caused by pollution on the coastal zone, as well as the problems of sea ice melting caused by global warming, an integrated, long-term study of the physical, chemical, and biological processes is needed.

Effects of Exercise on Physical and Mental Health, and Cognitive and Brain Functions in Schizophrenia: Clinical and Experimental Evidence.

PubMed

Rimes, Ridson Rosa; de Souza Moura, Antonio Marcos; Lamego, Murilo Khede; de Sá Filho, Alberto Souza; Manochio, João; Paes, Flávia; Carta, Mauro Giovanni; Mura, Gioia; Wegner, Mirko; Budde, Henning; Ferreira Rocha, Nuno Barbosa; Rocha, Joana; Tavares, João Manuel R S; Arias-Carrión, Oscar; Nardi, Antonio Egidio; Yuan, Ti-Fei; Machado, Sergio

2015-01-01

Exercise promotes several health benefits, such as cardiovascular, musculoskeletal and cardiorespiratory improvements. It is believed that the practice of exercise in individuals with psychiatric disorders, e.g. schizophrenia, can cause significant changes. Schizophrenic patients have problematic lifestyle habits compared with general population; this may cause a high mortality rate, mainly caused by cardiovascular and metabolic diseases. Thus, the aim of this study is to investigate changes in physical and mental health, cognitive and brain functioning due to the practice of exercise in patients with schizophrenia. Although still little is known about the benefits of exercise on mental health, cognitive and brain functioning of schizophrenic patients, exercise training has been shown to be a beneficial intervention in the control and reduction of disease severity. Type of training, form of execution, duration and intensity need to be better studied as the effects on physical and mental health, cognition and brain activity depend exclusively of interconnected factors, such as the combination of exercise and medication. However, one should understand that exercise is not only an effective nondrug alternative, but also acts as a supporting linking up interventions to promote improvements in process performance optimization. In general, the positive effects on mental health, cognition and brain activity as a result of an exercise program are quite evident. Few studies have been published correlating effects of exercise in patients with schizophrenia, but there is increasing evidence that positive and negative symptoms can be improved. Therefore, it is important that further studies be undertaken to expand the knowledge of physical exercise on mental health in people with schizophrenia, as well as its dose-response and the most effective type of exercise.

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

Bell, L.; Castaldi, A.; Jones, C.

The ultimate goal of the project is to develop procedures, techniques, data and other information that will aid in the design of cost effective and energy efficient drying processes that produce high quality foods. This objective has been sought by performing studies to determine the pertinent properties of food products, by developing models to describe the fundamental phenomena of food drying and by testing the models at laboratory scale. Finally, this information is used to develop recommendations and strategies for improved dryer design and control. This volume emphasizes a detailed literature review and several extensive experimental studies. Since the basicmore » principle of food dehydration is the removal of water from food, the process of removing water causes quality changes which can be categorized as physical, chemical, and nutritional. These changes often have adverse effects on the quality of the resulting dehydrated food. In this work, the types of physical and chemical changes common in food drying and the important factors for them were reviewed. Pertinent kinetic models and kinetic data reported in literature were also collected and compiled as the results of review study. The overall objectives of this study were to identify major quality change in foods caused by drying process and to get the knowledge of the relationship between the quality change and factors known to affect them. The quality parameters reviewed included: browning, lipid oxidation, color loss, shrinkage, solubility, texture, aroma and flavor, vitamin and protein loss and microbiological concerns. 54 refs., 74 figs., 49 tabs.« less

Detecting a Protein in its Natural Environment with a MOSFET Transistor

NASA Astrophysics Data System (ADS)

Perez, Benjamin; Balijepalli, Arvind

2015-03-01

Our group's goal is to make a MOSFET transistor that has a nanopore through it. We want to have proteins flow through this device and examine their structure based on the modulation they cause on the current. This process does not harm the protein and allows the protein to be studied in its natural environment. The electric field and electric potential of a point charge were computed within a nano-transistor. The simulations were used to see if the point charge had enough influence on the current to cause a modulation. The point charge did cause a rise in the current making the modulation concept a viable one for medical applications. COMSOL metaphysics software was used to perform all simulations. The Society of Physics Students internship program and NIST.

Sestrins: novel antioxidant and AMPK-modulating functions regulated by exercise?

PubMed

Sanchis-Gomar, Fabian

2013-08-01

Oxidative stress results from damage to tissues caused by free radicals and is increased by exercise. Peroxiredoxins (PRXs) maintain the cellular reducing environment by scavenging intracellular hydrogen peroxide. It has been recently noted that physical exercise has a positive effect on the PRX system, exerting a protective effect against oxidative stress-induced damage. However, other compounds, such as sestrins (SESNs), a stress-inducible protein family with antioxidant properties, should also be considered in the function of PRXs. SESNs are clearly involved in the regeneration process of PRXs and therefore may also be modulated by physical exercise. In addition, SESNs are clearly involved in TOR, AMPK, p53, FoxO, and PRXs signaling pathways. The aforementioned pathways are implicated in aging processes by inducing an increased resistance to subsequent stress, thus delaying age-related changes, such as sarcopenia and frailty, and consequently promoting longevity. Likewise, exercise also modulates these pathways. In fact, exercise is one of the most important recommended strategies to prevent sarcopenia and frailty, increase longevity, and improve health in the elderly. Loss of SESNs can cause several chronic pathologies, such as fat accumulation, mitochondrial dysfunction, cardiac arrhythmia, and/or muscle degeneration. Accordingly, physical inactivity leads to accumulation of visceral fat and consequently the activation of a network of inflammatory pathways, which promote development of insulin resistance, atherosclerosis, neurodegeneration, and tumor growth. To date, the SESNs-exercise relationship has not been explored. However, this emerging family of stress proteins may be part of the redox-based adaptive response to exercise. Copyright © 2013 Wiley Periodicals, Inc.

Aggregate stability as an indicator of soil erodibility and soil physical quality: review and perspectives

NASA Astrophysics Data System (ADS)

Le Bissonnais, Yves; Chenu, Claire; Darboux, Frédéric; Duval, Odile; Legout, Cédric; Leguédois, Sophie; Gumiere, Silvio

2010-05-01

Aggregate breakdown due to water and rain action may cause surface crusting, slumping, a reduction of infiltration and interrill erosion. Aggregate stability determines the capacity of aggregates to resist the effects of water and rainfall. In this paper, we evaluated and reviewed the relevance of an aggregate stability measurement to characterize soil physical properties as well as to analyse the processes involved in these properties. Stability measurement assesses the sensitivity of soil aggregates to various basic disaggregation mechanisms such as slaking, differential swelling, dispersion and mechanical breakdown. It has been showed that aggregate size distributions of structural stability tests matched the size distributions of eroded aggregates under rainfall simulations and that erosion amount was well predicted using aggregate stability indexes. It means stability tests could be used to estimate both the erodibility and the size fractions that are available for crust formation and erosion processes. Several studies showed that organic matter was one of the main soil properties affecting soil stability. However, it has also been showed that aggregate stability of a given soil could vary within a year or between years. The factors controlling such changes have still to be specified. Aggregate stability appears therefore as a complex property, depending both on permanent soil characteristics and on dynamic factors such as the crusting stage, the climate and the biological activity. Despite, and may be, because of this complexity, aggregate stability seems an integrative and powerful indicator of soil physical quality. Future research efforts should look at the causes of short-term changes of structural stability, in order to fully understand all its aspects.

Land use change impacts on floods at the catchment scale: Challenges and opportunities for future research

NASA Astrophysics Data System (ADS)

Rogger, M.; Agnoletti, M.; Alaoui, A.; Bathurst, J. C.; Bodner, G.; Borga, M.; Chaplot, V.; Gallart, F.; Glatzel, G.; Hall, J.; Holden, J.; Holko, L.; Horn, R.; Kiss, A.; Kohnová, S.; Leitinger, G.; Lennartz, B.; Parajka, J.; Perdigão, R.; Peth, S.; Plavcová, L.; Quinton, J. N.; Robinson, M.; Salinas, J. L.; Santoro, A.; Szolgay, J.; Tron, S.; van den Akker, J. J. H.; Viglione, A.; Blöschl, G.

2017-07-01

Research gaps in understanding flood changes at the catchment scale caused by changes in forest management, agricultural practices, artificial drainage, and terracing are identified. Potential strategies in addressing these gaps are proposed, such as complex systems approaches to link processes across time scales, long-term experiments on physical-chemical-biological process interactions, and a focus on connectivity and patterns across spatial scales. It is suggested that these strategies will stimulate new research that coherently addresses the issues across hydrology, soil and agricultural sciences, forest engineering, forest ecology, and geomorphology.

Sol-gel process for the manufacture of high power switches

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

Landingham, Richard L.; Satcher, Jr, Joe; Reibold, Robert

According to one embodiment, a photoconductive semiconductor switch includes a structure of nanopowder of a high band gap material, where the nanopowder is optically transparent, and where the nanopowder has a physical characteristic of formation from a sol-gel process. According to another embodiment, a method includes mixing a sol-gel precursor compound, a hydroxy benzene and an aldehyde in a solvent thereby creating a mixture, causing the mixture to gel thereby forming a wet gel, drying the wet gel to form a nanopowder, and applying a thermal treatment to form a SiC nanopowder.

The role of aggressions suffered by healthcare workers as predictors of burnout.

PubMed

Gascon, Santiago; Leiter, Michael P; Andrés, Eva; Santed, Miguel A; Pereira, Joao P; Cunha, María J; Albesa, Agustín; Montero-Marín, Jesus; García-Campayo, Javier; Martínez-Jarreta, Begoña

2013-11-01

To examine the prevalence of aggression against healthcare professionals and to determine the possible impact that violent episodes have on healthcare professionals in terms of loss of enthusiasm and involvement towards work. The objective was to analyse the percentage of occupational assault against professionals' aggression in different types of healthcare services, differentiating between physical and verbal aggression as a possible variable in detecting burnout in doctors and nursing professionals. Leiter and Maslach have explored a double process model of burnout not only based on exhaustion by overload, but also based on personal and organisational value conflicts (community, rewards or values). Moreover, Whittington has obtained conclusive results about the possible relationship between violence and burnout in mental health nurses. A retrospective study was performed in three hospitals and 22 primary care centres in Spain (n = 1·826). Through different questionnaires, we have explored the relationship between aggression suffered by healthcare workers and burnout. Eleven percent of respondents had been physically assaulted on at least one occasion, whilst 34·4% had suffered threats and intimidation on at least one occasion and 36·6% had been subjected to insults. Both forms of violence, physical and non-physical aggression, showed significant correlations with symptoms of burnout (emotional exhaustion, depersonalisation and inefficacy). The survey showed evidence of a double process: (1) by which excess workload helps predict burnout, and (2) by which a mismatch in the congruence of values, or interpersonal conflict, contributes in a meaningful way to each of the dimensions of burnout, adding overhead to the process of exhaustion-cynicism-lack of realisation. Relevance to clinical practice.  Studies indicate that health professionals are some of the most exposed to disorders steaming from psychosocial risks and a high comorbidity: anxiety, depression, etc. There is a clear need for accurate instruments of evaluation to detect not only the burnout but also the areas that cause it. Professional exhaustion caused by aggression or other factors can reflect a deterioration in the healthcare relationship. © 2012 Blackwell Publishing Ltd.

Circulating MicroRNAs as Potential Biomarkers of Exercise Response

PubMed Central

Polakovičová, Mája; Musil, Peter; Laczo, Eugen; Hamar, Dušan; Kyselovič, Ján

2016-01-01

Systematic physical activity increases physical fitness and exercise capacity that lead to the improvement of health status and athletic performance. Considerable effort is devoted to identifying new biomarkers capable of evaluating exercise performance capacity and progress in training, early detection of overtraining, and monitoring health-related adaptation changes. Recent advances in OMICS technologies have opened new opportunities in the detection of genetic, epigenetic and transcriptomic biomarkers. Very promising are mainly small non-coding microRNAs (miRNAs). miRNAs post-transcriptionally regulate gene expression by binding to mRNA and causing its degradation or inhibiting translation. A growing body of evidence suggests that miRNAs affect many processes and play a crucial role not only in cell differentiation, proliferation and apoptosis, but also affect extracellular matrix composition and maintaining processes of homeostasis. A number of studies have shown changes in distribution profiles of circulating miRNAs (c-miRNAs) associated with various diseases and disorders as well as in samples taken under physiological conditions such as pregnancy or physical exercise. This overview aims to summarize the current knowledge related to the response of blood c-miRNAs profiles to different modes of exercise and to highlight their potential application as a novel class of biomarkers of physical performance capacity and training adaptation. PMID:27782053

Differential diagnosis of endometriosis in a young adult woman with nonspecific low back pain.

PubMed

Troyer, Mark R

2007-06-01

Endometriosis is a common gynecological disorder that can cause musculoskeletal symptoms and manifest as nonspecific low back pain. The patient was a 25-year-old woman who reported the sudden onset of severe left-sided lumbosacral, lower quadrant, buttock, and thigh pain. The physical therapist examination revealed findings suggestive of a pelvic visceral disorder during the diagnostic process. The physical therapist referred the patient for medical consultation, and she was later diagnosed by a gynecologist with endometriosis and a left ovarian cyst. The patient underwent laser laparoscopy and excision of the ovarian cyst followed by a regimen of gonadotropin-releasing hormone agonists. The intervention resulted in abolition of the lower quadrant pain and a significant reduction of the back and leg pain that enabled the patient to return to her normal activities. A thorough physical therapist examination that considers all of the musculoskeletal, visceral, and psychosocial components is essential to identify pelvic disorders such as endometriosis and other disease processes during the differential diagnosis of nonspecific low back pain. Medical consultation is necessary to provide proper diagnosis and intervention of endometriosis, but physical therapists also may have an important role in the identification of endometriosis and the management of the musculoskeletal aspects of the disorder.

Optimum processing of mammographic film.

PubMed

Sprawls, P; Kitts, E L

1996-03-01

Underprocessing of mammographic film can result in reduced contrast and visibility of breast structures and an unnecessary increase in radiation dose to the patient. Underprocessing can be caused by physical factors (low developer temperature, inadequate development time, insufficient developer agitation) or chemical factors (developer not optimized for film type; overdiluted, underreplenished, contaminated, or frequently changed developer). Conventional quality control programs are designed to produce consistent processing but do not address the issue of optimum processing. Optimum processing is defined as the level of processing that produces the film performance characteristics (contrast and sensitivity) specified by the film manufacturer. Optimum processing of mammographic film can be achieved by following a two-step protocol. The first step is to set up the processing conditions according to recommendations from the film and developer chemistry manufacturers. The second step is to verify the processing results by comparing them with sensitometric data provided by the film manufacturer.

Production induced boiling and cold water entry in the Cerro Prieto geothermal reservoir indicated by chemical and physical measurements

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

Grant, M.A.; Truesdell, A.H.; Manon, A.

1981-01-01

Chemical and physical data suggest that the relatively shallow western part of the Cerro Prieto reservoir is bounded below by low permeability rocks, and above and at the sides by an interface with cooler water. There is no continuous permeability barrier around or immediately above the reservoir. Permeability within the reservoir is dominantly intergranular. Mixture with cooler water rather than boiling is the dominant cooling process in the natural state, and production causes displacement of hot water by cooler water, not by vapor. Local boiling occurs near most wells in response to pressure decreases, but no general vapor zone hasmore » formed.« less

Inactivation of Microorganisms

NASA Astrophysics Data System (ADS)

Alzamora, Stella Maris; Guerrero, Sandra N.; Schenk, Marcela; Raffellini, Silvia; López-Malo, Aurelio

Minimal processing techniques for food preservation allow better retention of product flavor, texture, color, and nutrient content than comparable conventional treatments. A wide range of novel alternative physical factors have been intensely investigated in the last two decades. These physical factors can cause inactivation of microorganisms at ambient or sublethal temperatures (e.g., high hydrostatic pressure, pulsed electric fields, ultrasound, pulsed light, and ultraviolet light). These technologies have been reported to reduce microorganism population in foods while avoiding the deleterious effects of severe heating on quality. Among technologies, high-energy ultrasound (i.e., intensities higher than 1 W/cm2, frequencies between 18 and 100 kHz) has attracted considerable interest for food preservation applications (Mason et al., 1996; Povey and Mason, 1998).

Physics-based approach to color image enhancement in poor visibility conditions.

PubMed

Tan, K K; Oakley, J P

2001-10-01

Degradation of images by the atmosphere is a familiar problem. For example, when terrain is imaged from a forward-looking airborne camera, the atmosphere degradation causes a loss in both contrast and color information. Enhancement of such images is a difficult task because of the complexity in restoring both the luminance and the chrominance while maintaining good color fidelity. One particular problem is the fact that the level of contrast loss depends strongly on wavelength. A novel method is presented for the enhancement of color images. This method is based on the underlying physics of the degradation process, and the parameters required for enhancement are estimated from the image itself.

Investigation of hypoxia off the Changjiang Estuary using a coupled model of ROMS-CoSiNE

NASA Astrophysics Data System (ADS)

Zhou, Feng; Chai, Fei; Huang, Daji; Xue, Huijie; Chen, Jianfang; Xiu, Peng; Xuan, Jiliang; Li, Jia; Zeng, Dingyong; Ni, Xiaobo; Wang, Kui

2017-12-01

The cause for large variability of hypoxia off the Changjiang Estuary has not been well understood partly due to various nutrient sources and complex physical-biological processes involved. The Regional Ocean Modeling Systems (ROMS) coupled with Carbon, Silicate and Nitrogen Ecosystem (CoSiNE) was used to investigate the 2006 hypoxia in the East China Sea, the largest hypoxia ever recorded. The model performance was evaluated comprehensively by comparing a suite of quantitative metrics, procedures and spatiotemporal patterns between the simulated results and observed data. The simulated results are generally consistent with the observations and are capable of reproducing the development of hypoxia and the observed vertical profiles of dissolved oxygen. Event-scale reduction of hypoxia occurred during the weakening of stratification in mid-July and mid-September, due to strong stirring caused by tropical storms or strong northerly wind. Change in wind direction altered the pathway of Changjiang Diluted Water and consequently caused variation in hypoxic location. Increase in river discharge led to an expansion of hypoxic water during the summer monsoon. Sensitivity analysis suggested that the hypoxia extent was affected by the change in nutrient concentration of the Changjiang as well as that of the Kuroshio. Sensitivity analysis also suggested the importance of sediment oxygen consumption to the size of the hypoxic zone. These results demonstrate that a prognostic 3D model is useful for investigating the highly variable hypoxia, with comprehensive considerations of multiple factors related to both physical and biological processes from the estuary to the shelf break of the East China Sea.

Follow-Up Care for Older Women With Breast Cancer

DTIC Science & Technology

1999-08-01

range of patient outcomes, including primary tumor therapy and mortality, self -reported upper body function, and overall physical function. Methods...mor therapy, all cause mortality, self -reported function and overall physical function than upper body function, and overall physical was the interview...Major Analytic Variables mor therapy and all cause mortality, as well as self -reported upper body and overall physical Dependent Variables. Our first

Service innovation: a comparison of two approaches for physical screening of psychiatric inpatients.

PubMed

Harrison, Mark Richard; McMillan, Catherine Frances; Dickinson, Timothy

2012-06-01

Psychiatric medications have clear links to obesity, diabetes, dyslipidaemia, hypertension, hyperprolactinaemia and movement disorders. These disorders are a common cause of morbidity and mortality in psychiatric patients but physical screening by health services is often haphazard. We report the findings of an audit of physical screening across two hospital wards. Each ward undertook a process of service improvement. One ward modified the admissions proforma and the other developed a discharge screening clinic. The effectiveness of each of these interventions was then compared through a reaudit of practice across both wards. At baseline, screening was performed inconsistently and infrequently. On average, the modified admissions proforma increased screening rates by 4.7% compared to 30.7% for discharge screening clinics. The discharge screening clinic demonstrated statistically significant improvements in screening rates and effectively delivered health promotion advice. Discharge screening clinics are significantly more likely than improved admissions procedures to detect clinically significant abnormalities. If these abnormalities are detected and treated then the long-term physical health of psychiatric patients may be improved.

The use of acoustic doppler meters to estimate sediment and nutrient concentrations in freshwater inflows to Texas coastal ecosystems

Treesearch

Zullmar Lucena; Micheal Lee

2016-01-01

Excessive sediment and nutrient loading are among the leading causes of impairment in water bodies of the United States due to their effect on biologic productivity, water quality, and aquatic food webs. Understanding the nutrient and suspended sediment loads affecting estuarine waters is fundamental to the assessment of the physical, chemical, and biological processes...

On the boundary conditions on a shock wave for hypersonic flow around a descent vehicle

NASA Astrophysics Data System (ADS)

Golomazov, M. M.; Ivankov, A. A.

2013-12-01

Stationary hypersonic flow around a descent vehicle is examined by considering equilibrium and nonequilibrium reactions. We study how physical-chemical processes and shock wave conditions for gas species influence the shock-layer structure. It is shown that conservation conditions of species on the shock wave cause high-temperature and concentration gradients in the shock layer when we calculate spacecraft deceleration trajectory in the atmosphere at 75 km altitude.

Assessing the detail needed to capture rainfall-runoff dynamics with physics-based hydrologic response simulation

USGS Publications Warehouse

Mirus, B.B.; Ebel, B.A.; Heppner, C.S.; Loague, K.

2011-01-01

Concept development simulation with distributed, physics-based models provides a quantitative approach for investigating runoff generation processes across environmental conditions. Disparities within data sets employed to design and parameterize boundary value problems used in heuristic simulation inevitably introduce various levels of bias. The objective was to evaluate the impact of boundary value problem complexity on process representation for different runoff generation mechanisms. The comprehensive physics-based hydrologic response model InHM has been employed to generate base case simulations for four well-characterized catchments. The C3 and CB catchments are located within steep, forested environments dominated by subsurface stormflow; the TW and R5 catchments are located in gently sloping rangeland environments dominated by Dunne and Horton overland flows. Observational details are well captured within all four of the base case simulations, but the characterization of soil depth, permeability, rainfall intensity, and evapotranspiration differs for each. These differences are investigated through the conversion of each base case into a reduced case scenario, all sharing the same level of complexity. Evaluation of how individual boundary value problem characteristics impact simulated runoff generation processes is facilitated by quantitative analysis of integrated and distributed responses at high spatial and temporal resolution. Generally, the base case reduction causes moderate changes in discharge and runoff patterns, with the dominant process remaining unchanged. Moderate differences between the base and reduced cases highlight the importance of detailed field observations for parameterizing and evaluating physics-based models. Overall, similarities between the base and reduced cases indicate that the simpler boundary value problems may be useful for concept development simulation to investigate fundamental controls on the spectrum of runoff generation mechanisms. Copyright 2011 by the American Geophysical Union.

Parameter Uncertainty on AGCM-simulated Tropical Cyclones

NASA Astrophysics Data System (ADS)

He, F.

2015-12-01

This work studies the parameter uncertainty on tropical cyclone (TC) simulations in Atmospheric General Circulation Models (AGCMs) using the Reed-Jablonowski TC test case, which is illustrated in Community Atmosphere Model (CAM). It examines the impact from 24 parameters across the physical parameterization schemes that represent the convection, turbulence, precipitation and cloud processes in AGCMs. The one-at-a-time (OAT) sensitivity analysis method first quantifies their relative importance on TC simulations and identifies the key parameters to the six different TC characteristics: intensity, precipitation, longwave cloud radiative forcing (LWCF), shortwave cloud radiative forcing (SWCF), cloud liquid water path (LWP) and ice water path (IWP). Then, 8 physical parameters are chosen and perturbed using the Latin-Hypercube Sampling (LHS) method. The comparison between OAT ensemble run and LHS ensemble run shows that the simulated TC intensity is mainly affected by the parcel fractional mass entrainment rate in Zhang-McFarlane (ZM) deep convection scheme. The nonlinear interactive effect among different physical parameters is negligible on simulated TC intensity. In contrast, this nonlinear interactive effect plays a significant role in other simulated tropical cyclone characteristics (precipitation, LWCF, SWCF, LWP and IWP) and greatly enlarge their simulated uncertainties. The statistical emulator Extended Multivariate Adaptive Regression Splines (EMARS) is applied to characterize the response functions for nonlinear effect. Last, we find that the intensity uncertainty caused by physical parameters is in a degree comparable to uncertainty caused by model structure (e.g. grid) and initial conditions (e.g. sea surface temperature, atmospheric moisture). These findings suggest the importance of using the perturbed physics ensemble (PPE) method to revisit tropical cyclone prediction under climate change scenario.

Structural and parameteric uncertainty quantification in cloud microphysics parameterization schemes

NASA Astrophysics Data System (ADS)

van Lier-Walqui, M.; Morrison, H.; Kumjian, M. R.; Prat, O. P.; Martinkus, C.

2017-12-01

Atmospheric model parameterization schemes employ approximations to represent the effects of unresolved processes. These approximations are a source of error in forecasts, caused in part by considerable uncertainty about the optimal value of parameters within each scheme -- parameteric uncertainty. Furthermore, there is uncertainty regarding the best choice of the overarching structure of the parameterization scheme -- structrual uncertainty. Parameter estimation can constrain the first, but may struggle with the second because structural choices are typically discrete. We address this problem in the context of cloud microphysics parameterization schemes by creating a flexible framework wherein structural and parametric uncertainties can be simultaneously constrained. Our scheme makes no assuptions about drop size distribution shape or the functional form of parametrized process rate terms. Instead, these uncertainties are constrained by observations using a Markov Chain Monte Carlo sampler within a Bayesian inference framework. Our scheme, the Bayesian Observationally-constrained Statistical-physical Scheme (BOSS), has flexibility to predict various sets of prognostic drop size distribution moments as well as varying complexity of process rate formulations. We compare idealized probabilistic forecasts from versions of BOSS with varying levels of structural complexity. This work has applications in ensemble forecasts with model physics uncertainty, data assimilation, and cloud microphysics process studies.

A fuzzy decision tree for fault classification.

PubMed

Zio, Enrico; Baraldi, Piero; Popescu, Irina C

2008-02-01

In plant accident management, the control room operators are required to identify the causes of the accident, based on the different patterns of evolution of the monitored process variables thereby developing. This task is often quite challenging, given the large number of process parameters monitored and the intense emotional states under which it is performed. To aid the operators, various techniques of fault classification have been engineered. An important requirement for their practical application is the physical interpretability of the relationships among the process variables underpinning the fault classification. In this view, the present work propounds a fuzzy approach to fault classification, which relies on fuzzy if-then rules inferred from the clustering of available preclassified signal data, which are then organized in a logical and transparent decision tree structure. The advantages offered by the proposed approach are precisely that a transparent fault classification model is mined out of the signal data and that the underlying physical relationships among the process variables are easily interpretable as linguistic if-then rules that can be explicitly visualized in the decision tree structure. The approach is applied to a case study regarding the classification of simulated faults in the feedwater system of a boiling water reactor.

[Physical activity in the prevention and treatment of diseases of affluence--the key role of AMP-activated protein kinase (AMPK)].

PubMed

Grochowska, Ewa; Jarzyna, Robert

2014-09-12

In developed countries, we can observe an increasing number of people with obesity, type 2 diabetes, dyslipidemia, hypertension and arteriosclerosis. The main reason for this phenomenon is the abnormal energy balance due to sedentary lifestyles. Cardiovascular diseases are the leading cause of death in many countries around the world, nowadays. In this paper, the impact of physical activity on the effectiveness of treatment and prevention of metabolic diseases and cancer is considered. Exercise is one of the factors activating 5'AMP-activated protein kinase (AMPK). This enzyme is crucial in maintaining the energy balance of the cell and the entire organism, and its activation results in excluding the anabolic and switching on the catabolic processes. It is believed that the activation of AMPK is responsible for most of the positive effects resulting from physical exercise. Although there are pharmacological methods of activation of this enzyme, they seem to be not as effective as physical exercise. Therefore, physical activity should be the most important form of prevention and treatment of metabolic diseases.

Constructor theory of information

PubMed Central

Deutsch, David; Marletto, Chiara

2015-01-01

We propose a theory of information expressed solely in terms of which transformations of physical systems are possible and which are impossible—i.e. in constructor-theoretic terms. It includes conjectured, exact laws of physics expressing the regularities that allow information to be physically instantiated. Although these laws are directly about information, independently of the details of particular physical instantiations, information is not regarded as an a priori mathematical or logical concept, but as something whose nature and properties are determined by the laws of physics alone. This theory solves a problem at the foundations of existing information theory, namely that information and distinguishability are each defined in terms of the other. It also explains the relationship between classical and quantum information, and reveals the single, constructor-theoretic property underlying the most distinctive phenomena associated with the latter, including the lack of in-principle distinguishability of some states, the impossibility of cloning, the existence of pairs of variables that cannot simultaneously have sharp values, the fact that measurement processes can be both deterministic and unpredictable, the irreducible perturbation caused by measurement, and locally inaccessible information (as in entangled systems). PMID:25663803

Impact of Psychopathy on Moral Judgments about Causing Fear and Physical Harm

PubMed Central

2015-01-01

Psychopathy is a personality variable associated with persistent immoral behaviors. Despite this, attempts to link moral reasoning deficits to psychopathic traits have yielded mixed results with many findings supporting intact moral reasoning in individuals with psychopathic traits. Abundant evidence shows that psychopathy impairs responses to others’ emotional distress. However, most studies of morality and psychopathy focus on judgments about causing others physical harm. Results of such studies may be inconsistent because physical harm is an imperfect proxy for emotional distress. No previous paradigm has explicitly separated judgments about physical harm and emotional distress and assessed how psychopathy affects each type of judgment. In three studies we found that psychopathy impairs judgments about causing others emotional distress (specifically fear) but minimally affects judgments about causing physical harm and that judgments about causing fear predict instrumental aggression in psychopathy. These findings are consistent with reports linking psychopathy to insensitivity to others’ fear, and suggest that sensitivity to others’ fear may play a fundamental role in the types of moral decision-making impaired by psychopathy. PMID:25992566

Effect of different concentrations of sodium dodecyl sulfate and additional anionic surfactant on properties of low protein natural rubber latex

NASA Astrophysics Data System (ADS)

Abdullah, Nurulhuda; Manaf, Siti Nor Qamarina; Hassan, Aziana Abu

2017-12-01

This paper describes the chemical deproteinization process of natural rubber latex (NRL) using chemical denaturants namely urea and sodium dodecyl sulfate (SDS). Commercial high ammoniated natural rubber latex (HANRL) was incubated with both denaturants - urea and SDS for selected period of time before centrifugation and characterization. The role of SDS in NRL deproteinization process was further elucidated by manipulating the concentration of SDS at 0.3 phr and 0.5 phr during the incubation process. It was found that the physical properties of NRL especially stability, were governed by the amount of SDS, whereby higher concentration of SDS used led to greater NRL stability. However, too much concentration of SDS in the system might cause detrimental effect on the properties of low protein NRL. The effects of additional anionic surfactant namely potassium laurate on the physical properties of low protein NRL and its stabilization were also scrutinized. Characterizations include nitrogen determination by Kjeldahl method, zeta potential, and morphological analysis by Field Emission Scanning Electron Microscopy (FESEM).

Astrophysical Flows

NASA Astrophysics Data System (ADS)

Pringle, James E.; King, Andrew

2003-07-01

Almost all conventional matter in the Universe is fluid, and fluid dynamics plays a crucial role in astrophysics. This new graduate textbook provides a basic understanding of the fluid dynamical processes relevant to astrophysics. The mathematics used to describe these processes is simplified to bring out the underlying physics. The authors cover many topics, including wave propagation, shocks, spherical flows, stellar oscillations, the instabilities caused by effects such as magnetic fields, thermal driving, gravity, shear flows, and the basic concepts of compressible fluid dynamics and magnetohydrodynamics. The authors are Directors of the UK Astrophysical Fluids Facility (UKAFF) at the University of Leicester, and editors of the Cambridge Astrophysics Series. This book has been developed from a course in astrophysical fluid dynamics taught at the University of Cambridge. It is suitable for graduate students in astrophysics, physics and applied mathematics, and requires only a basic familiarity with fluid dynamics.• Provides coverage of the fundamental fluid dynamical processes an astrophysical theorist needs to know • Introduces new mathematical theory and techniques in a straightforward manner • Includes end-of-chapter problems to illustrate the course and introduce additional ideas

Investigation of consolidation kinetics and microstructure evolution of Al alloys in direct metal laser sintering using phase field simulation

NASA Astrophysics Data System (ADS)

Bimal Satpathy, Bubloom; Nandy, Jyotirmoy; Sahoo, Seshadev

2018-03-01

Direct metal laser sintering is one of the very efficient processes which comes under the field of additive manufacturing and is capable of producing products of good mechanical and physical properties. The process parameters affect the physical and mechanical properties of the final products. Rapid solidification plays an important role in the consolidation kinetics as the powdered material sinters and forms a polycrystalline structure. In the recent times, the enormous use of computational modeling has helped in examining the utility of final products in a wide range of applications. In this study, a phase field model has been implemented to foresee the consolidation kinetics during the liquid state sintering. Temperature profiles have been used to study the densification behavior and neck growth which is caused by the surface diffusion of particles at initial stage. Later, importance of grain boundary and the volume diffusion during densification process is analyzed. It is also found that with rise in temperature, neck growth also increases rapidly due to the interaction of adjacent grains through grain boundary diffusion and stabilization of grain growth.

Effects of structural modification on reliability of nanoscale nitride HEMTs

NASA Astrophysics Data System (ADS)

Gaddipati, Vamsi Mohan

AlGaN based nanoscale high-electron-mobility transistors (HEMTs) are the next generation of transistor technology that features the unique combination of higher power, wider bandwidth, low noise, higher efficiency, and temperature/radiation hardness than conventional AlGaAs and Si based technologies. However, as evidenced by recent stress tests, reliability of these devices (characterized by a gradual decrease in the output current/power leading to failure of the device in just tens of hours of operation) remains a major concern. Although, in these tests, physical damages were clearly visible in the device, the root cause and nature of these damages have not yet been fully assessed experimentally. Therefore, a comprehensive theoretical study of the physical mechanisms responsible for degradation of AlGaN HEMTs is essential before these devices are deployed in targeted applications. The main objective of the proposed research is to computationally investigate how degradation of state-of-the-art nanoscale AlGaN HEMTs is governed by an intricate and dynamical coupling of thermo-electromechanical processes at different length (atoms-to-transistor) and time (femtosecondto- hours) scales while operating in high voltage, large mechanical, and high temperature/radiation stresses. This work centers around a novel hypotheses as follows: High voltage applied to AlGaN HEMT causes excessive internal heat dissipation, which triggers gate metal diffusion into the semiconducting barrier layer and structural modifications (defect ii formation) leading to diminished polarization induced charge density and output current. Since the dynamical system to be studied is complex, chaotic (where the evolution rule is guided by atomicity of the underlying material), and involve coupled physical processes, an in-house multiscale simulator (QuADS 3-D) has been employed and augmented, where material parameters are obtained atomistically using firstprinciples, structural relaxation and defect formations will be modeled by integrating molecular dynamics, and the influence of atomistic processes on charge and phonon transport and current degradation will be simulated using a coupled drift-diffusionthermodynamic framework.

Bidirectional Classical Stochastic Processes with Measurements and Feedback

NASA Technical Reports Server (NTRS)

Hahne, G. E.

2005-01-01

A measurement on a quantum system is said to cause the "collapse" of the quantum state vector or density matrix. An analogous collapse occurs with measurements on a classical stochastic process. This paper addresses the question of describing the response of a classical stochastic process when there is feedback from the output of a measurement to the input, and is intended to give a model for quantum-mechanical processes that occur along a space-like reaction coordinate. The classical system can be thought of in physical terms as two counterflowing probability streams, which stochastically exchange probability currents in a way that the net probability current, and hence the overall probability, suitably interpreted, is conserved. The proposed formalism extends the . mathematics of those stochastic processes describable with linear, single-step, unidirectional transition probabilities, known as Markov chains and stochastic matrices. It is shown that a certain rearrangement and combination of the input and output of two stochastic matrices of the same order yields another matrix of the same type. Each measurement causes the partial collapse of the probability current distribution in the midst of such a process, giving rise to calculable, but non-Markov, values for the ensuing modification of the system's output probability distribution. The paper concludes with an analysis of a classical probabilistic version of the so-called grandfather paradox.

[The effect of physical therapy on the most severe forms of knee structral changes caused by osteoarthritis].

PubMed

Kapidzić-Basić, Nedima; Dzananović, Dzevad; Kapidzić-Duraković, Suada; Kikanović, Sahza; Mulić-Bacić, Suada; Hotić-Hadziefendić, Asja

2011-01-01

In the most severe form of structural changes on knee caused by osteoarthritis non-surgical treatment provide minimal results and a question of its purpose is being raised. Aim of the study was to examine the possibilities of physical treatment of patients with the most severe degree of structural changes caused by knee osteoarthritis. Examination was conducted on 60 patients that were on physical treatment because of the knee OA. Structural changes are evaluated by Kellgren-Lawrence scale, functional ability by Lequesne index, and pain by Visual analog scale. Physical treatment lasted for 4 weeks. After the physical treatment there was a significant improvement of functional ability (p = 1.78E-07), but the size of improvement was reduced by the level of structural changes. It was significantly lower in IV class in relation to III and II class (p < 0.05). Physical treatment has lower affect by patients with the most severe form of structural changes caused by knee osteoarthritis, but it still can help patients to ease the appearance of complete dependence on other people's help.

The causes of high power diode laser brazed seams fractures of dissimilar materials

NASA Astrophysics Data System (ADS)

Adamiak, Marcin; Czupryński, Artur; Janicki, Damian; Górka, Jacek

2016-12-01

Presented in this article are the results of experiments carried out to determine the causes of braze cracking of dissimilar materials brazed with a ROFIN DL 020 high power diode laser with the use of additional powdered EN AW-1070A aluminium alloy to bond thin aluminium sheets with soft, low alloy DC04+ZE75/75 steel plate which was electrolytically coated with zinc on both sides. Presented are the results of metallographic, macroscopic, microscopic, diffractometric phase analyses of the weld joints. Metallurgical problems arising during processing as well as suggestions regarding technical aspects of laser brazing dissimilar materials in regards to their physical characteristics and chemical composition are explored.

Entropic cohering power in quantum operations

NASA Astrophysics Data System (ADS)

Xi, Zhengjun; Hu, Ming-Liang; Li, Yongming; Fan, Heng

2018-02-01

Coherence is a basic feature of quantum systems and a common necessary condition for quantum correlations. It is also an important physical resource in quantum information processing. In this paper, using relative entropy, we consider a more general definition of the cohering power of quantum operations. First, we calculate the cohering power of unitary quantum operations and show that the amount of distributed coherence caused by non-unitary quantum operations cannot exceed the quantum-incoherent relative entropy between system of interest and its environment. We then find that the difference between the distributed coherence and the cohering power is larger than the quantum-incoherent relative entropy. As an application, we consider the distributed coherence caused by purification.

Physical assault in the previous year and total and cause-specific mortality in Russia: a case–control study of men aged 25–54 years

PubMed Central

Bhavsar, Vishal; Cook, Sarah; Saburova, Lyudmila; Leon, David A

2017-01-01

Abstract Background: Violence has important health effects. The results of exposure to physical violence include, but may not be limited to, death from suicide and homicide. The connection between the experience of assault and risk of death from causes other than homicide and suicide has rarely been examined. Methods: We analysed data from the first Izhevsk Family Study (IFS-1), a population-based case–control study of premature mortality in Russian men. Structural equation models were used to obtain odds ratios (ORs) for the association between the proxy report of physical attack in the previous year and mortality. Results: The estimate of the all-cause mortality OR for assault, after adjusting for alcohol use and socio-demographic confounders, was 1.96 (95% confidence interval: 1.71, 3.31). Strong cause-specific associations were found for external causes, but associations were also found for deaths from cardiovascular and alcohol-related deaths. Conclusions: We found that, in our population of working-aged Russian men, there was a strong association between physical assault and mortality from a wide range of causes. Other than direct effects of physical assault on mortality, residual confounding is an important possibility. The association between assault and mortality, particularly from cardiovascular and alcohol-related causes requires replication and further investigation. PMID:28031312

Physical scales in the Wigner–Boltzmann equation

PubMed Central

Nedjalkov, M.; Selberherr, S.; Ferry, D.K.; Vasileska, D.; Dollfus, P.; Querlioz, D.; Dimov, I.; Schwaha, P.

2013-01-01

The Wigner–Boltzmann equation provides the Wigner single particle theory with interactions with bosonic degrees of freedom associated with harmonic oscillators, such as phonons in solids. Quantum evolution is an interplay of two transport modes, corresponding to the common coherent particle-potential processes, or to the decoherence causing scattering due to the oscillators. Which evolution mode will dominate depends on the scales of the involved physical quantities. A dimensionless formulation of the Wigner–Boltzmann equation is obtained, where these scales appear as dimensionless strength parameters. A notion called scaling theorem is derived, linking the strength parameters to the coupling with the oscillators. It is shown that an increase of this coupling is equivalent to a reduction of both the strength of the electric potential, and the coherence length. Secondly, the existence of classes of physically different, but mathematically equivalent setups of the Wigner–Boltzmann evolution is demonstrated. PMID:23504194

Modeling aeolian dune and dune field evolution

NASA Astrophysics Data System (ADS)

Diniega, Serina

Aeolian sand dune morphologies and sizes are strongly connected to the environmental context and physical processes active since dune formation. As such, the patterns and measurable features found within dunes and dune fields can be interpreted as records of environmental conditions. Using mathematical models of dune and dune field evolution, it should be possible to quantitatively predict dune field dynamics from current conditions or to determine past field conditions based on present-day observations. In this dissertation, we focus on the construction and quantitative analysis of a continuum dune evolution model. We then apply this model towards interpretation of the formative history of terrestrial and martian dunes and dune fields. Our first aim is to identify the controls for the characteristic lengthscales seen in patterned dune fields. Variations in sand flux, binary dune interactions, and topography are evaluated with respect to evolution of individual dunes. Through the use of both quantitative and qualitative multiscale models, these results are then extended to determine the role such processes may play in (de)stabilization of the dune field. We find that sand flux variations and topography generally destabilize dune fields, while dune collisions can yield more similarly-sized dunes. We construct and apply a phenomenological macroscale dune evolution model to then quantitatively demonstrate how dune collisions cause a dune field to evolve into a set of uniformly-sized dunes. Our second goal is to investigate the influence of reversing winds and polar processes in relation to dune slope and morphology. Using numerical experiments, we investigate possible causes of distinctive morphologies seen in Antarctic and martian polar dunes. Finally, we discuss possible model extensions and needed observations that will enable the inclusion of more realistic physical environments in the dune and dune field evolution models. By elucidating the qualitative and quantitative connections between environmental conditions, physical processes, and resultant dune and dune field morphologies, this research furthers our ability to interpret spacecraft images of dune fields, and to use present-day observations to improve our understanding of past terrestrial and martian environments.

Does the benefit on survival from leisure time physical activity depend on physical activity at work? A prospective cohort study.

PubMed

Holtermann, Andreas; Marott, Jacob Louis; Gyntelberg, Finn; Søgaard, Karen; Suadicani, Poul; Mortensen, Ole Steen; Prescott, Eva; Schnohr, Peter

2013-01-01

To investigate if persons with high physical activity at work have the same benefits from leisure time physical activity as persons with sedentary work. In the Copenhagen City Heart Study, a prospective cohort of 7,411 males and 8,916 females aged 25-66 years without known cardiovascular disease at entry in 1976-78, 1981-83, 1991-94, or 2001-03, the authors analyzed with sex-stratified multivariate Cox proportional hazards regression the association between leisure time physical activity and cardiovascular and all-cause mortality among individuals with different levels of occupational physical activity. During a median follow-up of 22.4 years, 4,003 individuals died from cardiovascular disease and 8,935 from all-causes. Irrespective of level of occupational physical activity, a consistently lower risk with increasing leisure time physical activity was found for both cardiovascular and all-cause mortality among both men and women. Compared to low leisure time physical activity, the survival benefit ranged from 1.5-3.6 years for moderate and 2.6-4.7 years for high leisure time physical activity among the different levels of occupational physical activity. Public campaigns and initiatives for increasing physical activity in the working population should target everybody, irrespective of physical activity at work.

Physical scales in the Wigner-Boltzmann equation

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

Nedjalkov, M., E-mail: mixi@iue.tuwien.ac.at; Selberherr, S.; Ferry, D.K.

2013-01-15

The Wigner-Boltzmann equation provides the Wigner single particle theory with interactions with bosonic degrees of freedom associated with harmonic oscillators, such as phonons in solids. Quantum evolution is an interplay of two transport modes, corresponding to the common coherent particle-potential processes, or to the decoherence causing scattering due to the oscillators. Which evolution mode will dominate depends on the scales of the involved physical quantities. A dimensionless formulation of the Wigner-Boltzmann equation is obtained, where these scales appear as dimensionless strength parameters. A notion called scaling theorem is derived, linking the strength parameters to the coupling with the oscillators. Itmore » is shown that an increase of this coupling is equivalent to a reduction of both the strength of the electric potential, and the coherence length. Secondly, the existence of classes of physically different, but mathematically equivalent setups of the Wigner-Boltzmann evolution is demonstrated. - Highlights: Black-Right-Pointing-Pointer Dimensionless parameters determine the ratio of quantum or classical WB evolution. Black-Right-Pointing-Pointer The scaling theorem evaluates the decoherence effect due to scattering. Black-Right-Pointing-Pointer Evolution processes are grouped into classes of equivalence.« less

Corrosion processes of physical vapor deposition-coated metallic implants.

PubMed

Antunes, Renato Altobelli; de Oliveira, Mara Cristina Lopes

2009-01-01

Protecting metallic implants from the harsh environment of physiological fluids is essential to guaranteeing successful long-term use in a patient's body. Chemical degradation may lead to the failure of an implant device in two different ways. First, metal ions may cause inflammatory reactions in the tissues surrounding the implant and, in extreme cases, these reactions may inflict acute pain on the patient and lead to loosening of the device. Therefore, increasing wear strength is beneficial to the performance of the metallic implant. Second, localized corrosion processes contribute to the nucleation of fatigue cracks, and corrosion fatigue is the main reason for the mechanical failure of metallic implants. Common biomedical alloys such as stainless steel, cobalt-chrome alloys, and titanium alloys are prone to at least one of these problems. Vapor-deposited hard coatings act directly to improve corrosion, wear, and fatigue resistances of metallic materials. The effectiveness of the corrosion protection is strongly related to the structure of the physical vapor deposition layer. The aim of this paper is to present a comprehensive review of the correlation between the structure of physical vapor deposition layers and the corrosion properties of metallic implants.

Dynamic behavior of the weld pool in stationary GMAW

NASA Astrophysics Data System (ADS)

Chapuis, J.; Romero, E.; Bordreuil, C.; Soulié, F.; Fras, G.

2010-06-01

Because hump formation limits welding productivity, better understanding of the humping phenomena during the welding process is needed to access to process modifications that decrease the tendency for hump formation and then allow higher productivity welding. From a physical point of view, the mechanism identified is the Rayleigh instability initiated by strong surface tension gradient which induces a variation of kinetic flow. But the causes of the appearance of this instability are not yet well explained. Because of the phenomena complex and multi-physics, we chose in first step to conduct an analysis of the characteristic times involved in weld pool in pulsed stationary GMAW. The goal is to study the dynamic behavior of the weld pool, using our experimental multi physics approach. The experimental tool and methodology developed to understand these fast phenomena are presented first: frames acquisition with high speed digital camera and specific optical devices, numerical library. The analysis of geometric parameters of the weld pool during welding operation are presented in the last part: we observe the variations of wetting angles (or contact lines angles), the base and the height of the weld pool (macro-drop) versus weld time.

Future climate risk from compound events

NASA Astrophysics Data System (ADS)

Zscheischler, Jakob; Westra, Seth; van den Hurk, Bart J. J. M.; Seneviratne, Sonia I.; Ward, Philip J.; Pitman, Andy; AghaKouchak, Amir; Bresch, David N.; Leonard, Michael; Wahl, Thomas; Zhang, Xuebin

2018-06-01

Floods, wildfires, heatwaves and droughts often result from a combination of interacting physical processes across multiple spatial and temporal scales. The combination of processes (climate drivers and hazards) leading to a significant impact is referred to as a `compound event'. Traditional risk assessment methods typically only consider one driver and/or hazard at a time, potentially leading to underestimation of risk, as the processes that cause extreme events often interact and are spatially and/or temporally dependent. Here we show how a better understanding of compound events may improve projections of potential high-impact events, and can provide a bridge between climate scientists, engineers, social scientists, impact modellers and decision-makers, who need to work closely together to understand these complex events.

Introduction to Particle Acceleration in the Cosmos

NASA Technical Reports Server (NTRS)

Gallagher, D. L.; Horwitz, J. L.; Perez, J.; Quenby, J.

2005-01-01

Accelerated charged particles have been used on Earth since 1930 to explore the very essence of matter, for industrial applications, and for medical treatments. Throughout the universe nature employs a dizzying array of acceleration processes to produce particles spanning twenty orders of magnitude in energy range, while shaping our cosmic environment. Here, we introduce and review the basic physical processes causing particle acceleration, in astrophysical plasmas from geospace to the outer reaches of the cosmos. These processes are chiefly divided into four categories: adiabatic and other forms of non-stochastic acceleration, magnetic energy storage and stochastic acceleration, shock acceleration, and plasma wave and turbulent acceleration. The purpose of this introduction is to set the stage and context for the individual papers comprising this monograph.

Graphene nanoribbons: Relevance of etching process

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

Simonet, P., E-mail: psimonet@phys.ethz.ch; Bischoff, D.; Moser, A.

2015-05-14

Most graphene nanoribbons in the experimental literature are patterned using plasma etching. Various etching processes induce different types of defects and do not necessarily result in the same electronic and structural ribbon properties. This study focuses on two frequently used etching techniques, namely, O{sub 2} plasma ashing and O{sub 2 }+ Ar reactive ion etching (RIE). O{sub 2} plasma ashing represents an alternative to RIE physical etching for sensitive substrates, as it is a more gentle chemical process. We find that plasma ashing creates defective graphene in the exposed trenches, resulting in instabilities in the ribbon transport. These are probably caused bymore » more or larger localized states at the edges of the ashed device compared to the RIE defined device.« less

Changes in orientation and shape of protoplanetary discs moving through an ambient medium

NASA Astrophysics Data System (ADS)

Wijnen, T. P. G.; Pelupessy, F. I.; Pols, O. R.; Portegies Zwart, S.

2017-08-01

Misalignments between the orbital planes of planets and the equatorial planes of their host stars have been observed in our solar system, in transiting exoplanets, and for the orbital planes of debris discs. We present a mechanism that causes such a spin-orbit misalignment for a protoplanetary disc due to its movement through an ambient medium. Our physical explanation of the mechanism is based on the theoretical solutions to the Stark problem. We test this idea by performing self-consistent hydrodynamical simulations and simplified gravitational N-body simulations. The N-body model reduces the mechanism to the relevant physical processes. The hydrodynamical simulations show the mechanism in its full extent, including gas-dynamical and viscous processes in the disc which are not included in the theoretical framework. We find that a protoplanetary disc embedded in a flow changes its orientation as its angular momentum vector tends to align parallel to the relative velocity vector. Due to the force exerted by the flow, orbits in the disc become eccentric, which produces a net torque and consequentially changes the orbital inclination. The tilting of the disc causes it to contract. Apart from becoming lopsided, the gaseous disc also forms a spiral arm even if the inclination does not change substantially. The process is most effective at high velocities and observational signatures are therefore mostly expected in massive star-forming regions and around winds or supernova ejecta. Our N-body model indicates that the interaction with supernova ejecta is a viable explanation for the observed spin-orbit misalignment in our solar system.

Possible cause for an improbable earthquake: The 1997 MW 4.9 southern Alabama earthquake and hydrocarbon recovery

USGS Publications Warehouse

Gomberg, J.; Wolf, L.

1999-01-01

Circumstantial and physical evidence indicates that the 1997 MW 4.9 earthquake in southern Alabama may have been related to hydrocarbon recovery. Epicenters of this earthquake and its aftershocks were located within a few kilometers of active oil and gas extraction wells and two pressurized injection wells. Main shock and aftershock focal depths (2-6 km) are within a few kilometers of the injection and withdrawal depths. Strain accumulation at geologic rates sufficient to cause rupture at these shallow focal depths is not likely. A paucity of prior seismicity is difficult to reconcile with the occurrence of an earthquake of MW 4.9 and a magnitude-frequency relationship usually assumed for natural earthquakes. The normal-fault main-shock mechanism is consistent with reactivation of preexisting faults in the regional tectonic stress field. If the earthquake were purely tectonic, however, the question arises as to why it occurred on only the small fraction of a large, regional fault system coinciding with active hydrocarbon recovery. No obvious temporal correlation is apparent between the earthquakes and recovery activities. Although thus far little can be said quantitatively about the physical processes that may have caused the 1997 sequence, a plausible explanation involves the poroelastic response of the crust to extraction of hydrocarbons.

The Coast Artillery Journal. Volume 64, Number 4, April 1926

DTIC Science & Technology

1926-04-01

to be the next era of civilization, the answer would be, "We are now entering the era of catalytics, the age of physical chemistry ." The connection...that promises to revolutionize every process of chemistry knoVtll of and radically to alter our methods of refining and using hydrocarbons. The...The War: Its Causes and Consequences. 1864. 260 pp. Farrar, G. P. How Advertisements are Built. 1925. 2% pp. Foster, W. The Elements of Chemistry . 1925

Treatment and recovery.

PubMed

Raia, Susan

2005-01-01

Addiction is a chronic, progressive, fatal disease. It is a primary disease, not caused by any other disease process. It has recognizable symptoms that if left untreated, can lead to premature death, deterioration of physical conditions, social withdrawal and disintegration of all support systems. The family and co-workers are affected as well. There is no cure, but we know that treatment works! Don't stand by while someone you care about needs help. Nurses helping nurses, let's take care of our own.

Investigation of the Impedance Modulation of Thin Films with a Chemically-Sensitive Field-Effect Transistor

DTIC Science & Technology

1988-12-05

CHEMFET, both in the time-domain and frequency domain, was evaluated for detecting changes in the molecular structure and chemical composition in three thin...compounds cause corrosion of the munition’s firing mechanism (3). The military also has substantial interest in the use of composite materials for...fabricating military hardware (4). However, the synthesis of a composite material is highly process dependent, and thus, its physical properties may

Objective detection and forecasting of Clear-Air Turbulence (CAT): A status report

NASA Technical Reports Server (NTRS)

Keller, John L.

1988-01-01

Clear-air turbulence has become the largest single cause of weather-related injuries occurring in commercial carriers at cruising altitudes. A technique for objective operational CAT detection (the SCATR index) has been formulated. Its physical basis ties CAT to total energy dissipation as a response to meso- and synoptic-scale dynamical processes associated with upper-level jet stream/frontal zones. Early case studies using properly analyzed routine RAOB rawinsonde sounding data have shown promise.

Medical conditions with neuropsychiatric manifestations.

PubMed

Isaac, Margaret L; Larson, Eric B

2014-09-01

Medical disease sometimes affects patients through neuropsychiatric manifestations. When neuropsychiatric symptoms are predominant, identifying medical disease early in the illness course is imperative because many of these conditions are reversible with appropriate treatment. A high index of suspicion is required on the part of clinicians, particularly when patients also present with physical signs or unexplained symptoms that might suggest a broader, systemic process. The processes that most commonly cause neuropsychiatric symptoms include infectious, autoimmune, endocrinologic, metabolic, and neoplastic diseases. This article focuses on the most common of these conditions, and conditions for which early diagnosis and treatment are particularly important. Copyright © 2014 Elsevier Inc. All rights reserved.

The role of CFD in the design process

NASA Astrophysics Data System (ADS)

Jennions, Ian K.

1994-05-01

Over the last decade the role played by CFD codes in turbomachinery design has changed remarkably. While convergence/stability or even the existence of unique solutions was discussed fervently ten years ago, CFD codes now form a valuable part of an overall integrated design system and have caused us to re-think much of what we do. The geometric and physical complexities addressed have also evolved, as have the number of software houses competing with in-house developers to provide solutions to daily design problems. This paper reviews how GE Aircraft Engines (GEAE) uses CFD in the turbomachinery design process and examines many of the issues faced in successful code implementation.

Sugarcane-Biorefinery.

PubMed

Vaz, Sílvio

2017-03-17

Concepts such as biorefinery and green chemistry focus on the usage of biomass, as with the oil value chain. However, it can cause less negative impact on the environment. A biorefinery based on sugarcane (Saccharum spp.) as feedstock is an example, because it can integrate into the same physical space, of processes for obtaining biofuels (ethanol), chemicals (from sugars or ethanol), electricity, and heat.The use of sugarcane as feedstock for biorefineries is dictated by its potential to supply sugars, ethanol, natural polymers or macromolecules, organic matter, and other compounds and materials. By means of conversion processes (chemical, biochemical, and thermochemical), sugarcane biomass can be transformed into high-value bioproducts to replace petrochemicals, as a bioeconomy model.

Composite substrate for bipolar electrodes

DOEpatents

Tekkanat, Bora; Bolstad, James J.

1992-12-22

Substrates for electrode systems, particularly those to be used for bipolar electrodes in zinc-bromine batteries, are disclosed. The substrates preferably include carbon-black as a conductive filler in a polymeric matrix, with reinforcing materials such as glass fibers. Warpage of the zinc-bromine electrodes which was experienced in the prior art and which was believed to be caused by physical expansion of the electrodes due to bromine absorption by the carbon-black, is substantially eliminated when new substrate fabrication techniques are employed. In the pesent invention, substrates are prepared using a lamination process known as glass mat reinforced thermoplastics technology or, in an alternate embodiment, the substrate is made using a slurry process.

On the control of riverbed incision induced by run-of-river power plant

NASA Astrophysics Data System (ADS)

Bizzi, Simone; Dinh, Quang; Bernardi, Dario; Denaro, Simona; Schippa, Leonardo; Soncini-Sessa, Rodolfo

2015-07-01

Water resource management (WRM) through dams or reservoirs is worldwide necessary to support key human-related activities, ranging from hydropower production to water allocation and flood risk mitigation. Designing of reservoir operations aims primarily to fulfill the main purpose (or purposes) for which the structure has been built. However, it is well known that reservoirs strongly influence river geomorphic processes, causing sediment deficits downstream, altering water, and sediment fluxes, leading to riverbed incision and causing infrastructure instability and ecological degradation. We propose a framework that, by combining physically based modeling, surrogate modeling techniques, and multiobjective (MO) optimization, allows to include fluvial geomorphology into MO optimization whose main objectives are the maximization of hydropower revenue and the minimization of riverbed degradation. The case study is a run-of-the-river power plant on the River Po (Italy). A 1-D mobile-bed hydro-morphological model simulated the riverbed evolution over a 10 year horizon for alternatives operation rules of the power plant. The knowledge provided by such a physically based model is integrated into a MO optimization routine via surrogate modeling using the response surface methodology. Hence, this framework overcomes the high computational costs that so far hindered the integration of river geomorphology into WRM. We provided numerical proof that river morphologic processes and hydropower production are indeed in conflict but that the conflict may be mitigated with appropriate control strategies.

Formation mechanism of gas bubble superlattice in UMo metal fuels: Phase-field modeling investigation

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

Hu, Shenyang; Burkes, Douglas E.; Lavender, Curt A.

2016-07-08

Nano-gas bubble superlattices are often observed in irradiated UMo nuclear fuels. However, the for- mation mechanism of gas bubble superlattices is not well understood. A number of physical processes may affect the gas bubble nucleation and growth; hence, the morphology of gas bubble microstructures including size and spatial distributions. In this work, a phase-field model integrating a first-passage Monte Carlo method to investigate the formation mechanism of gas bubble superlattices was devel- oped. Six physical processes are taken into account in the model: 1) heterogeneous generation of gas atoms, vacancies, and interstitials informed from atomistic simulations; 2) one-dimensional (1-D) migration of interstitials; 3) irradiation-induced dissolution of gas atoms; 4) recombination between vacancies and interstitials; 5) elastic interaction; and 6) heterogeneous nucleation of gas bubbles. We found that the elastic interaction doesn’t cause the gas bubble alignment, and fast 1-D migration of interstitials alongmore » $$\\langle$$110$$\\rangle$$ directions in the body-centered cubic U matrix causes the gas bubble alignment along $$\\langle$$110$$\\rangle$$ directions. It implies that 1-D interstitial migration along [110] direction should be the primary mechanism of a fcc gas bubble superlattice which is observed in bcc UMo alloys. Simulations also show that fission rates, saturated gas concentration, and elastic interaction all affect the morphology of gas bubble microstructures.« less

Numerical simulation of a low-lying barrier island's morphological response to Hurricane Katrina

USGS Publications Warehouse

Lindemer, C.A.; Plant, N.G.; Puleo, J.A.; Thompson, D.M.; Wamsley, T.V.

2010-01-01

Tropical cyclones that enter or form in the Gulf of Mexico generate storm surge and large waves that impact low-lying coastlines along the Gulf Coast. The Chandeleur Islands, located 161. km east of New Orleans, Louisiana, have endured numerous hurricanes that have passed nearby. Hurricane Katrina (landfall near Waveland MS, 29 Aug 2005) caused dramatic changes to the island elevation and shape. In this paper the predictability of hurricane-induced barrier island erosion and accretion is evaluated using a coupled hydrodynamic and morphodynamic model known as XBeach. Pre- and post-storm island topography was surveyed with an airborne lidar system. Numerical simulations utilized realistic surge and wave conditions determined from larger-scale hydrodynamic models. Simulations included model sensitivity tests with varying grid size and temporal resolutions. Model-predicted bathymetry/topography and post-storm survey data both showed similar patterns of island erosion, such as increased dissection by channels. However, the model under predicted the magnitude of erosion. Potential causes for under prediction include (1) errors in the initial conditions (the initial bathymetry/topography was measured three years prior to Katrina), (2) errors in the forcing conditions (a result of our omission of storms prior to Katrina and/or errors in Katrina storm conditions), and/or (3) physical processes that were omitted from the model (e.g., inclusion of sediment variations and bio-physical processes). ?? 2010.

[Effects of land use change on carbon storage in terrestrial ecosystem].

PubMed

Yang, Jingcheng; Han, Xingguo; Huang, Jianhui; Pan, Qingmin

2003-08-01

Terrestrial ecosystem is an important carbon pool, which plays a crucial role in carbon biogeochemical cycle. Human activities such as fossil fuel combustion and land use change have resulted in carbon fluxes from terrestrial ecosystem to the atmosphere, which increased the atmospheric CO2 concentration, and reinforced the greenhouse effect. Land use change affects the structure and function of the terrestrial ecosystem, which causes its change of carbon storage. To a great extent, the change of carbon storage lies in the type of ecosystem and the change of land use patterns. The conversion of forest to agricultural land and pasture causes a large reduction of carbon storage in vegetation and soil, and the decrease of soil carbon concentration is mainly caused by the reduction of detritus, the acceleration of soil organic matter decomposition, and the destroy of physical protection to organic matter due to agricultural practices. The loss of soil organic matter appears at the early stage after deforestation, and the loss rate is influenced by many factors and soil physical, chemical and biological processes. The conversion of agricultural land and pasture to forest and many conservative agricultural practices can sequester atmospheric carbon in vegetation and soil. Vegetation can sequester large amounts of carbon from atmosphere, while carbon accumulation in soil varies greatly because of farming history and soil spatial heterogeneity. Conservative agricultural practices such as no-tillage, reasonable cropping system, and fertilization can influence soil physical and chemical characters, plant growth, quality and quantity of stubble, and soil microbial biomass and its activity, and hence, maintain and increase soil carbon concentration.

Investigation of the Perceived Causes of Pre-Service Physics Teachers' Problems Encountered in School Experience

ERIC Educational Resources Information Center

Körhasan, Nilüfer Didis; Didis, M. Gözde

2015-01-01

This study investigates a group of pre-service physics teachers' perceptions about the causes of problems in school experience through the attribution theory. The participants were thirteen pre-service physics teachers from a public university in Turkey. Data were collected through the interviews by requesting the participants to reflect their own…

Effect on physical fitness of a 10-year physical activity intervention in primary health care settings.

PubMed

Nakamura, Priscila M; Papini, Camila B; Teixeira, Inaian P; Chiyoda, Alberto; Luciano, Eliete; Cordeira, Kelly Lynn; Kokubun, Eduardo

2015-01-01

Interventions in primary health care settings have been effective in increasing physical fitness. In 2001, the Programa de Exercício Físico em Unidades de Saúde (Physical Exercise in Health Primary Care Program-PEHPCP) was launched in Rio Claro City, Brazil. The intervention consisted of biweekly, 60-minute group sessions in all primary health care settings in the city. This study evaluated the effect of PEHPCP on physical fitness and on the aging process after a decade of ongoing implementation. There were 409 women (50 ± 26 y old) and 31 men (64 ± 10 y old) who were eligible for this study. Every 4 months, participants completed the American Alliance for Health, Physical Education, Recreation and Dance standardized tests. Program participation was associated with a reduced effect, compared with baseline, of the natural decline of physical fitness caused by aging, as represented by changes in the following measures: coordination test time, -0.44 seconds; agility and dynamic balance test time; -1.81 seconds; aerobic capacity test time, 3.57 seconds; and muscle strength exercises, +0.60 repetitions. No significant effect on flexibility was found. The PEHPCP showed potential in improving muscle strength, coordination, aerobic capacity, and agility and dynamic balance in participants and in maintaining flexibility in participants.

Impact of the Ageing on Viscoelastic Properties of Bitumen with the Liquid Surface Active Agent at Operating Temperatures

NASA Astrophysics Data System (ADS)

Iwański, Marek; Cholewińska, Malgorzata; Mazurek, Grzegorz

2017-10-01

The paper presents the influence of the ageing on viscoelastic properties of the bitumen at road pavement operating temperatures. The ageing process of bituminous binders causes changes in physical and mechanical properties of the bitumen. This phenomenon takes place in all stages of bituminous mixtures manufacturing, namely: mixing, storage, transport, placing. Nevertheless, during the service life it occurs the increase in stiffness of asphalt binder that is caused by the physical hardening of bitumen as well as the influence of oxidation. Therefore, it is important to identify the binder properties at a high and low operating temperatures of asphalt pavement after simulation of an ageing process. In the experiment as a reference bitumen, the polymer modified bitumen PMB 45/80-65 was used. The liquid surface active agent FA (fatty amine) was used as a bitumen viscosity-reducing modifier. It was added in the amount of 0,2%, 0,4% and 0,6% by the bitumen mass. All binder properties have been determined before ageing (NEAT) and after long-term ageing simulated by the Pressure Ageing Vessel method (PAV). To determine the binder properties at high temperatures the dynamic viscosity at 60°C was tested. On the basis of test results coming from the dynamic viscosity test it was calculated the binder hardening index. The properties at a low temperature were determined by measuring the creep modulus using Bending Beam Rheometer (BBR) at four temperatures: -10°C, -16°C, -22°C and -28°C. The stiffness creep modulus “S” and parameter “m” were determined. On the basis of dynamic viscosity test it was found that the ageing process caused a slight decrease in a dynamic viscosity. The level of a hardening index considerably increased at 0.6% fatty amine content. The long-term ageing process had a minor effect on stiffening of a polymer modified bitumen with FA additive regardless of a low temperature and an amount of fatty amine content.

Thermobaricity, cabbeling, and water-mass conversion

NASA Astrophysics Data System (ADS)

McDougall, Trevor J.

1987-05-01

The efficient mixing of heat and salt along neutral surfaces (by mesoscale eddies) is shown to lead to vertical advection through these neutral surfaces. This is due to the nonlinearities of the equation of state of seawater through terms like ∂2ρ/∂θ∂p (thermobaric effect) and ∂2ρ/∂ θ2 (cabbeling). Cabbeling always causes a sinking or downwelling of fluid through neutral surfaces, whereas thermobaricity can lead to a vertical velocity (relative to neutral surfaces) of either sign. In this paper it is shown that for reasonable values of the lateral scalar diffusivity (especially below a depth of 1000 m), these two processes cause vertical velocities of the order of 10-7 m s-1 through neutral surfaces (usually downward!) and cause water-mass conversion of a magnitude equal to that caused by a vertical diffusivity of 10-4 m2 s-1 (often equivalent to a negative diffusivity). Both thermobaricity and cabbeling can occur in the presence of any nonzero amount of small-scale turbulence and so will not be detected by microstructure measurements. The conservation equations for tracers are considered in a nonorthogonal coordinate frame that moves with neutral surfaces in the ocean. Since only mixing processes cause advection across neutral surfaces, it is useful to regard this vertical advection as a symptom of various mixing processes rather than as a separate physical process. It is possible to derive conservative equations for scalars that do not contain the vertical advective term explicity. In these conservation equations, the terms that represent mixing processes are substantially altered. It is argued that this form of the conservation equations is the most appropriate when considering water-mass transformation, and some examples are given of its application in the North Atlantic. It is shown that the variation of the vertical diffusivity with height does not cause water-mass transformation. Also, salt fingering is often 3-4 times more effective at changing the potential temperature of a water mass than would be implied by simply calculating the vertical derivative of the fingering heat flux.

A Review of Criticality Accidents 2000 Revision

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

Thomas P. McLaughlin; Shean P. Monahan; Norman L. Pruvost

Criticality accidents and the characteristics of prompt power excursions are discussed. Sixty accidental power excursions are reviewed. Sufficient detail is provided to enable the reader to understand the physical situation, the chemistry and material flow, and when available the administrative setting leading up to the time of the accident. Information on the power history, energy release, consequences, and causes are also included when available. For those accidents that occurred in process plants, two new sections have been included in this revision. The first is an analysis and summary of the physical and neutronic features of the chain reacting systems. Themore » second is a compilation of observations and lessons learned. Excursions associated with large power reactors are not included in this report.« less

An Exploratory Study of Cost Engineering in Axiomatic Design: Creation of the Cost Model Based on an FR-DP Map

NASA Technical Reports Server (NTRS)

Lee, Taesik; Jeziorek, Peter

2004-01-01

Large complex projects cost large sums of money throughout their life cycle for a variety of reasons and causes. For such large programs, the credible estimation of the project cost, a quick assessment of the cost of making changes, and the management of the project budget with effective cost reduction determine the viability of the project. Cost engineering that deals with these issues requires a rigorous method and systematic processes. This paper introduces a logical framework to a&e effective cost engineering. The framework is built upon Axiomatic Design process. The structure in the Axiomatic Design process provides a good foundation to closely tie engineering design and cost information together. The cost framework presented in this paper is a systematic link between the functional domain (FRs), physical domain (DPs), cost domain (CUs), and a task/process-based model. The FR-DP map relates a system s functional requirements to design solutions across all levels and branches of the decomposition hierarchy. DPs are mapped into CUs, which provides a means to estimate the cost of design solutions - DPs - from the cost of the physical entities in the system - CUs. The task/process model describes the iterative process ot-developing each of the CUs, and is used to estimate the cost of CUs. By linking the four domains, this framework provides a superior traceability from requirements to cost information.

Recommendations and illustrations for the evaluation of photonic random number generators

NASA Astrophysics Data System (ADS)

Hart, Joseph D.; Terashima, Yuta; Uchida, Atsushi; Baumgartner, Gerald B.; Murphy, Thomas E.; Roy, Rajarshi

2017-09-01

The never-ending quest to improve the security of digital information combined with recent improvements in hardware technology has caused the field of random number generation to undergo a fundamental shift from relying solely on pseudo-random algorithms to employing optical entropy sources. Despite these significant advances on the hardware side, commonly used statistical measures and evaluation practices remain ill-suited to understand or quantify the optical entropy that underlies physical random number generation. We review the state of the art in the evaluation of optical random number generation and recommend a new paradigm: quantifying entropy generation and understanding the physical limits of the optical sources of randomness. In order to do this, we advocate for the separation of the physical entropy source from deterministic post-processing in the evaluation of random number generators and for the explicit consideration of the impact of the measurement and digitization process on the rate of entropy production. We present the Cohen-Procaccia estimate of the entropy rate h (𝜖 ,τ ) as one way to do this. In order to provide an illustration of our recommendations, we apply the Cohen-Procaccia estimate as well as the entropy estimates from the new NIST draft standards for physical random number generators to evaluate and compare three common optical entropy sources: single photon time-of-arrival detection, chaotic lasers, and amplified spontaneous emission.

Active liquid-like behavior of nucleoli determines their size and shape in Xenopus laevis oocytes

PubMed Central

Brangwynne, Clifford P.; Mitchison, Timothy J.; Hyman, Anthony A.

2011-01-01

For most intracellular structures with larger than molecular dimensions, little is known about the connection between underlying molecular activities and higher order organization such as size and shape. Here, we show that both the size and shape of the amphibian oocyte nucleolus ultimately arise because nucleoli behave as liquid-like droplets of RNA and protein, exhibiting characteristic viscous fluid dynamics even on timescales of < 1 min. We use these dynamics to determine an apparent nucleolar viscosity, and we show that this viscosity is ATP-dependent, suggesting a role for active processes in fluidizing internal contents. Nucleolar surface tension and fluidity cause their restructuring into spherical droplets upon imposed mechanical deformations. Nucleoli exhibit a broad distribution of sizes with a characteristic power law, which we show is a consequence of spontaneous coalescence events. These results have implications for the function of nucleoli in ribosome subunit processing and provide a physical link between activity within a macromolecular assembly and its physical properties on larger length scales. PMID:21368180

Active liquid-like behavior of nucleoli determines their size and shape in Xenopus laevis oocytes.

PubMed

Brangwynne, Clifford P; Mitchison, Timothy J; Hyman, Anthony A

2011-03-15

For most intracellular structures with larger than molecular dimensions, little is known about the connection between underlying molecular activities and higher order organization such as size and shape. Here, we show that both the size and shape of the amphibian oocyte nucleolus ultimately arise because nucleoli behave as liquid-like droplets of RNA and protein, exhibiting characteristic viscous fluid dynamics even on timescales of < 1 min. We use these dynamics to determine an apparent nucleolar viscosity, and we show that this viscosity is ATP-dependent, suggesting a role for active processes in fluidizing internal contents. Nucleolar surface tension and fluidity cause their restructuring into spherical droplets upon imposed mechanical deformations. Nucleoli exhibit a broad distribution of sizes with a characteristic power law, which we show is a consequence of spontaneous coalescence events. These results have implications for the function of nucleoli in ribosome subunit processing and provide a physical link between activity within a macromolecular assembly and its physical properties on larger length scales.

A Dynamical Systems Explanation of the Hurst Effect and Atmospheric Low-Frequency Variability

PubMed Central

Franzke, Christian L. E.; Osprey, Scott M.; Davini, Paolo; Watkins, Nicholas W.

2015-01-01

The Hurst effect plays an important role in many areas such as physics, climate and finance. It describes the anomalous growth of range and constrains the behavior and predictability of these systems. The Hurst effect is frequently taken to be synonymous with Long-Range Dependence (LRD) and is typically assumed to be produced by a stationary stochastic process which has infinite memory. However, infinite memory appears to be at odds with the Markovian nature of most physical laws while the stationarity assumption lacks robustness. Here we use Lorenz's paradigmatic chaotic model to show that regime behavior can also cause the Hurst effect. By giving an alternative, parsimonious, explanation using nonstationary Markovian dynamics, our results question the common belief that the Hurst effect necessarily implies a stationary infinite memory process. We also demonstrate that our results can explain atmospheric variability without the infinite memory previously thought necessary and are consistent with climate model simulations. PMID:25765880

Growing swimming algae for bioenergy

NASA Astrophysics Data System (ADS)

Croze, Ottavio

Biofuel production from photosynthetic microalgae is not commercially viable due to high processing costs. New engineering and biological solutions are being sought to reduce these costs by increasing processing efficiency (productivity per energy input). Important physics, however, is ignored. For example, the fluid dynamics of algal suspensions in photobioreactors (ponds or tube arrays) is non-trivial, particularly if the algae swim. Cell reorientation by passive viscous and gravitational torques (gyrotaxis) or active reorientation by light (phototaxis) cause swimming algae in suspension to structure in flows, even turbulent ones. This impacts the distribution and dispersion of swimmers, with significant consequences for photobioreactor operation and design. In this talk, I will describe a theory that predicts swimmer dispersion in laminar pipe flows. I will then then present experimental tests of the theory, as well as new results on the circadian suspension dynamics of the algaChlamydomonas reinhardtii in lab-scale photobioreactors. Finally, I will briefly consider the implications of our work, and related active matter research, for improving algal bioprocessing efficiency. Winton Programme for the Physics of Sustainability.

Anatomy of an incident

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

Cournoyer, Michael E.; Trujillo, Stanley; Lawton, Cindy M.

A traditional view of incidents is that they are caused by shortcomings in human competence, attention, or attitude. It may be under the label of “loss of situational awareness,” procedure “violation,” or “poor” management. A different view is that human error is not the cause of failure, but a symptom of failure – trouble deeper inside the system. In this perspective, human error is not the conclusion, but rather the starting point of investigations. During an investigation, three types of information are gathered: physical, documentary, and human (recall/experience). Through the causal analysis process, apparent cause or apparent causes are identifiedmore » as the most probable cause or causes of an incident or condition that management has the control to fix and for which effective recommendations for corrective actions can be generated. A causal analysis identifies relevant human performance factors. In the following presentation, the anatomy of a radiological incident is discussed, and one case study is presented. We analyzed the contributing factors that caused a radiological incident. When underlying conditions, decisions, actions, and inactions that contribute to the incident are identified. This includes weaknesses that may warrant improvements that tolerate error. Measures that reduce consequences or likelihood of recurrence are discussed.« less

Anatomy of an incident

DOE PAGES

Cournoyer, Michael E.; Trujillo, Stanley; Lawton, Cindy M.; ...

2016-03-23

A traditional view of incidents is that they are caused by shortcomings in human competence, attention, or attitude. It may be under the label of “loss of situational awareness,” procedure “violation,” or “poor” management. A different view is that human error is not the cause of failure, but a symptom of failure – trouble deeper inside the system. In this perspective, human error is not the conclusion, but rather the starting point of investigations. During an investigation, three types of information are gathered: physical, documentary, and human (recall/experience). Through the causal analysis process, apparent cause or apparent causes are identifiedmore » as the most probable cause or causes of an incident or condition that management has the control to fix and for which effective recommendations for corrective actions can be generated. A causal analysis identifies relevant human performance factors. In the following presentation, the anatomy of a radiological incident is discussed, and one case study is presented. We analyzed the contributing factors that caused a radiological incident. When underlying conditions, decisions, actions, and inactions that contribute to the incident are identified. This includes weaknesses that may warrant improvements that tolerate error. Measures that reduce consequences or likelihood of recurrence are discussed.« less

DNA double-strand-break complexity levels and their possible contributions to the probability for error-prone processing and repair pathway choice.

PubMed

Schipler, Agnes; Iliakis, George

2013-09-01

Although the DNA double-strand break (DSB) is defined as a rupture in the double-stranded DNA molecule that can occur without chemical modification in any of the constituent building blocks, it is recognized that this form is restricted to enzyme-induced DSBs. DSBs generated by physical or chemical agents can include at the break site a spectrum of base alterations (lesions). The nature and number of such chemical alterations define the complexity of the DSB and are considered putative determinants for repair pathway choice and the probability that errors will occur during this processing. As the pathways engaged in DSB processing show distinct and frequently inherent propensities for errors, pathway choice also defines the error-levels cells opt to accept. Here, we present a classification of DSBs on the basis of increasing complexity and discuss how complexity may affect processing, as well as how it may cause lethal or carcinogenic processing errors. By critically analyzing the characteristics of DSB repair pathways, we suggest that all repair pathways can in principle remove lesions clustering at the DSB but are likely to fail when they encounter clusters of DSBs that cause a local form of chromothripsis. In the same framework, we also analyze the rational of DSB repair pathway choice.

Analysis of urban metabolic processes based on input-output method: model development and a case study for Beijing

NASA Astrophysics Data System (ADS)

Zhang, Yan; Liu, Hong; Chen, Bin; Zheng, Hongmei; Li, Yating

2014-06-01

Discovering ways in which to increase the sustainability of the metabolic processes involved in urbanization has become an urgent task for urban design and management in China. As cities are analogous to living organisms, the disorders of their metabolic processes can be regarded as the cause of "urban disease". Therefore, identification of these causes through metabolic process analysis and ecological element distribution through the urban ecosystem's compartments will be helpful. By using Beijing as an example, we have compiled monetary input-output tables from 1997, 2000, 2002, 2005, and 2007 and calculated the intensities of the embodied ecological elements to compile the corresponding implied physical input-output tables. We then divided Beijing's economy into 32 compartments and analyzed the direct and indirect ecological intensities embodied in the flows of ecological elements through urban metabolic processes. Based on the combination of input-output tables and ecological network analysis, the description of multiple ecological elements transferred among Beijing's industrial compartments and their distribution has been refined. This hybrid approach can provide a more scientific basis for management of urban resource flows. In addition, the data obtained from distribution characteristics of ecological elements may provide a basic data platform for exploring the metabolic mechanism of Beijing.

CADDIS Volume 2. Sources, Stressors and Responses: Physical Habitat

EPA Pesticide Factsheets

Introduction to the Physical Habitat module, when to list Physical Habitat as a candidate cause, ways to measure Physical Habitat, simple and detailed conceptual diagrams for Physical Habitat, Physical Habitat module references and literature reviews.

Physical modelling of LNG rollover in a depressurized container filled with water

NASA Astrophysics Data System (ADS)

Maksim, Dadonau; Denissenko, Petr; Hubert, Antoine; Dembele, Siaka; Wen, Jennifer

2015-11-01

Stable density stratification of multi-component Liquefied Natural Gas causes it to form distinct layers, with upper layer having a higher fraction of the lighter components. Heat flux through the walls and base of the container results in buoyancy-driven convection accompanied by heat and mass transfer between the layers. The equilibration of densities of the top and bottom layers, normally caused by the preferential evaporation of Nitrogen, may induce an imbalance in the system and trigger a rapid mixing process, so-called rollover. Numerical simulation of the rollover is complicated and codes require validation. Physical modelling of the phenomenon has been performed in a water-filled depressurized vessel. Reducing gas pressure in the container to levels comparable to the hydrostatic pressure in the water column allows modelling of tens of meters industrial reservoirs using a 20 cm laboratory setup. Additionally, it allows to model superheating of the base fluid layer at temperatures close the room temperature. Flow visualizations and parametric studies are presented. Results are related to outcomes of numerical modelling.

Housework Reduces All-Cause and Cancer Mortality in Chinese Men

PubMed Central

Yu, Ruby; Leung, Jason; Woo, Jean

2013-01-01

Background Leisure time physical activity has been extensively studied. However, the health benefits of non-leisure time physical activity, particular those undertaken at home on all-cause and cancer mortality are limited, particularly among the elderly. Methods We studied physical activity in relation to all-cause and cancer mortality in a cohort of 4,000 community-dwelling elderly aged 65 and older. Leisure time physical activity (sport/recreational activity and lawn work/yard care/gardening) and non-leisure time physical activity (housework, home repairs and caring for another person) were self-reported on the Physical Activity Scale for the Elderly. Subjects with heart diseases, stroke, cancer or diabetes at baseline were excluded (n = 1,133). Results Among the 2,867 subjects with a mean age of 72 years at baseline, 452 died from all-cause and 185 died from cancer during the follow-up period (2001–2012). With the adjustment for age, education level and lifestyle factors, we found an inverse association between risk of all-cause mortality and heavy housework among men, with the adjusted hazard ratio (HR) of 0.72 (95%CI = 0.57–0.92). Further adjustment for BMI, frailty index, living arrangement, and leisure time activity did not change the result (HR = 0.71, 95%CI = 0.56–0.91). Among women, however, heavy housework was not associated with all-cause mortality. The risk of cancer mortality was significantly lower among men who participated in heavy housework (HR = 0.52, 95%CI = 0.35–0.78), whereas among women the risk was not significant. Men participated in light housework also were at lower risk of cancer mortality than were their counterparts, however, the association was not significant. Leisure time physical activity was not related to all-cause or cancer mortality in either men or women. Conclusion Heavy housework is associated with reduced mortality and cancer deaths over a 9-year period. The underlying mechanism needs further study. PMID:23667441

Does the Benefit on Survival from Leisure Time Physical Activity Depend on Physical Activity at Work? A Prospective Cohort Study

PubMed Central

Holtermann, Andreas; Marott, Jacob Louis; Gyntelberg, Finn; Søgaard, Karen; Suadicani, Poul; Mortensen, Ole Steen; Prescott, Eva; Schnohr, Peter

2013-01-01

Purpose To investigate if persons with high physical activity at work have the same benefits from leisure time physical activity as persons with sedentary work. Methods In the Copenhagen City Heart Study, a prospective cohort of 7,411 males and 8,916 females aged 25–66 years without known cardiovascular disease at entry in 1976–78, 1981–83, 1991–94, or 2001–03, the authors analyzed with sex-stratified multivariate Cox proportional hazards regression the association between leisure time physical activity and cardiovascular and all-cause mortality among individuals with different levels of occupational physical activity. Results During a median follow-up of 22.4 years, 4,003 individuals died from cardiovascular disease and 8,935 from all-causes. Irrespective of level of occupational physical activity, a consistently lower risk with increasing leisure time physical activity was found for both cardiovascular and all-cause mortality among both men and women. Compared to low leisure time physical activity, the survival benefit ranged from 1.5–3.6 years for moderate and 2.6–4.7 years for high leisure time physical activity among the different levels of occupational physical activity. Conclusion Public campaigns and initiatives for increasing physical activity in the working population should target everybody, irrespective of physical activity at work. PMID:23349926

Sox21 deletion in mice causes postnatal growth deficiency without physiological disruption of hypothalamic-pituitary endocrine axes

PubMed Central

Cheung, Leonard Y. M.; Okano, Hideyuki

2016-01-01

The hypothalamic-pituitary axes are the coordinating centers for multiple endocrine gland functions and physiological processes. Defects in the hypothalamus or pituitary gland can cause reduced growth and severe short stature, affecting approximately 1 in 4000 children, and a large percentage of cases of pituitary hormone deficiencies do not have an identified genetic cause. SOX21 is a protein that regulates hair, neural, and trophoblast stem cell differentiation. Mice lacking Sox21 have reduced growth, but the etiology of this growth defect has not been described. We studied the expression of Sox21 in hypothalamic-pituitary development and examined multiple endocrine axes in these mice. We find no evidence of reduced intrauterine growth, food intake, or physical activity, but there is evidence for increased energy expenditure in mutants. In addition, despite changes in pituitary hormone expression, hypothalamic-pituitary axes appear to be functional. Therefore, SOX21 variants may be a cause of non-endocrine short stature in humans. PMID:27616671

The neck mass. 2. Inflammatory and neoplastic causes.

PubMed

Damion, J; Hybels, R L

1987-05-01

Several inflammatory processes can cause nodules or swelling in the neck. A complete physical examination and, usually, laboratory testing are required to establish the diagnosis. Common infections include cervical lymphadenitis and tuberculous lymphadenitis, cat-scratch disease, infection in the neck spaces, infectious mononucleosis, and syphilis. Primary or metastatic cancer may also be the cause. Cervical metastasis often presents as a neck mass. Although a primary tumor may not be found immediately when a neck mass is being evaluated, one is often discovered later. Other types of malignancy that may be present are histiocytic lymphoma, Hodgkin's disease, rhabdomyosarcoma, thyroid cancer, and a salivary (most often parotid) gland tumor. Symptomatic treatment is sometimes adequate for infectious disease, but administration of antituberculous drugs or antibiotics may also be necessary. Incision and drainage are required for some nodes and abscesses. For neck masses caused by neoplasms, fine-needle aspiration cytology or biopsy is performed. Depending on the diagnosis, treatment consists of dissection, radiation therapy, and/or chemotherapy.

Effect of Power Ultrasound on Food Quality

NASA Astrophysics Data System (ADS)

Lee, Hyoungill; Feng, Hao

Recent food processing technology innovations have been centered around producing foods with fresh-like attributes through minimal processing or nonthermal processing technologies. Instead of using thermal energy to secure food safety that is often accompanied by quality degradation in processed foods, the newly developed processing modalities utilize other types of physical energy such as high pressure, pulsed electric field or magnetic field, ultraviolet light, or acoustic energy to process foods. An improvement in food quality by the new processing methods has been widely reported. In comparison with its low-energy (high-frequency) counterpart which finds applications in food quality inspection, the use of high-intensity ultrasound, also called power ultrasound, in food processing is a relatively new endeavor. To understand the effect of high-intensity ultrasound treatment on food quality, it is important to understand the interactions between acoustic energy and food ingredients, which is covered in Chapter 10. In this chapter, the focus will be on changes in overall food quality attributes that are caused by ultrasound, such as texture, color, flavor, and nutrients.

CADDIS Volume 2. Sources, Stressors and Responses: Physical Habitat - Simple Conceptual Diagram

EPA Pesticide Factsheets

Introduction to the Physical Habitat module, when to list Physical Habitat as a candidate cause, ways to measure Physical Habitat, simple and detailed conceptual diagrams for Physical Habitat, Physical Habitat module references and literature reviews.

CADDIS Volume 2. Sources, Stressors and Responses: Physical Habitat - Detailed Conceptual Diagram

EPA Pesticide Factsheets

Introduction to the Physical Habitat module, when to list Physical Habitat as a candidate cause, ways to measure Physical Habitat, simple and detailed conceptual diagrams for Physical Habitat, Physical Habitat module references and literature reviews.

An overview of natural hazard impacts to railways and urban transportation systems

NASA Astrophysics Data System (ADS)

Bíl, Michal; Nezval, Vojtěch; Bílová, Martina; Andrášik, Richard; Kubeček, Jan

2017-04-01

We present an overview and two case studies of natural hazard impacts on rail transportation systems in the Czech Republic. Flooding, landsliding, heavy snowfall, windstorms and glaze (black ice) are the most common natural processes which occur in this region. Whereas flooding and landsliding usually cause direct damage to the transportation infrastructure, other hazards predominantly cause indirect losses. Railway and urban tramline networks are almost fully dependent on electricity which is provided by a system of overhead lines (electric lines above the tracks). These lines are extremely susceptible to formation of glaze which blocks conduction of electric current. A December 2014 glaze event caused significant indirect losses in the largest Czech cities and railways due to the above-mentioned process. Details of this event will be provided during the presentation. Windstorms usually cause tree falls which can affect overhead lines and physically block railway tracks. Approximately 30 % of the Czech railway network is closer than 50 m from the nearest forest. This presents significant potential for transport interruption due to falling trees. Complicated legal relations among the owners of the plots of land along railways, the environment (full-grown trees and related habitat), and the railway administrator are behind many traffic interruptions due to falling trees. We have registered 2040 tree falls between 2012 and 2015 on the railway network. A model of the fallen tree hazard was created for the entire Czech railway network. Both above-mentioned case studies provide illustrative examples of the increased fragility of the modern transportation systems which fully rely on electricity. Natural processes with a low destructive power are thereby able to cause network wide service cut-offs.

Editorial

NASA Astrophysics Data System (ADS)

Preis, T.

2011-03-01

The two articles in this issue of the European Physical Journal Special Topics cover topics in Econophysics and GPU computing in the last years. In the first article [1], the formation of market prices for financial assets is described which can be understood as superposition of individual actions of market participants, in which they provide cumulative supply and demand. This concept of macroscopic properties emerging from microscopic interactions among the various subcomponents of the overall system is also well-known in statistical physics. The distribution of price changes in financial markets is clearly non-Gaussian leading to distinct features of the price process, such as scaling behavior, non-trivial correlation functions and clustered volatility. This article focuses on the analysis of financial time series and their correlations. A method is used for quantifying pattern based correlations of a time series. With this methodology, evidence is found that typical behavioral patterns of financial market participants manifest over short time scales, i.e., that reactions to given price patterns are not entirely random, but that similar price patterns also cause similar reactions. Based on the investigation of the complex correlations in financial time series, the question arises, which properties change when switching from a positive trend to a negative trend. An empirical quantification by rescaling provides the result that new price extrema coincide with a significant increase in transaction volume and a significant decrease in the length of corresponding time intervals between transactions. These findings are independent of the time scale over 9 orders of magnitude, and they exhibit characteristics which one can also find in other complex systems in nature (and in physical systems in particular). These properties are independent of the markets analyzed. Trends that exist only for a few seconds show the same characteristics as trends on time scales of several months. Thus, it is possible to study financial bubbles and their collapses in more detail, because trend switching processes occur with higher frequency on small time scales. In addition, a Monte Carlo based simulation of financial markets is analyzed and extended in order to reproduce empirical features and to gain insight into their causes. These causes include both financial market microstructure and the risk aversion of market participants.

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

Bacon, L. D.

Hybrid Band{trademark} (H-band) is a Lockheed Martin Missiles and Fire Control (LMMFC) designation for a specific RF modulation that causes disruption of select electronic components and circuits. H-Band enables conventional high-power microwave (HPM) effects (with a center frequency of 1 to 2 GHz, for example) using a higher frequency carrier signal. The primary technical objective of this project was to understand the fundamental physics of Hybrid Band{trademark} Radio Frequency effects on electronic systems. The follow-on objective was to develop and validate a Hybrid Band{trademark} effects analysis process.

Radiation belt electron acceleration during the 17 March 2015 geomagnetic storm: Observations and simulations

DOE PAGES

Li, W.; Ma, Q.; Thorne, R. M.; ...

2016-06-10

Various physical processes are known to cause acceleration, loss, and transport of energetic electrons in the Earth's radiation belts, but their quantitative roles in different time and space need further investigation. During the largest storm over the past decade (17 March 2015), relativistic electrons experienced fairly rapid acceleration up to ~7 MeV within 2 days after an initial substantial dropout, as observed by Van Allen Probes. In the present paper, we evaluate the relative roles of various physical processes during the recovery phase of this large storm using a 3-D diffusion simulation. By quantitatively comparing the observed and simulated electronmore » evolution, we found that chorus plays a critical role in accelerating electrons up to several MeV near the developing peak location and produces characteristic flat-top pitch angle distributions. By only including radial diffusion, the simulation underestimates the observed electron acceleration, while radial diffusion plays an important role in redistributing electrons and potentially accelerates them to even higher energies. Moreover, plasmaspheric hiss is found to provide efficient pitch angle scattering losses for hundreds of keV electrons, while its scattering effect on > 1 MeV electrons is relatively slow. Although an additional loss process is required to fully explain the overestimated electron fluxes at multi-MeV, the combined physical processes of radial diffusion and pitch angle and energy diffusion by chorus and hiss reproduce the observed electron dynamics remarkably well, suggesting that quasi-linear diffusion theory is reasonable to evaluate radiation belt electron dynamics during this big storm.« less

Radiation belt electron acceleration during the 17 March 2015 geomagnetic storm: Observations and simulations

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

Li, W.; Ma, Q.; Thorne, R. M.

Various physical processes are known to cause acceleration, loss, and transport of energetic electrons in the Earth's radiation belts, but their quantitative roles in different time and space need further investigation. During the largest storm over the past decade (17 March 2015), relativistic electrons experienced fairly rapid acceleration up to ~7 MeV within 2 days after an initial substantial dropout, as observed by Van Allen Probes. In the present paper, we evaluate the relative roles of various physical processes during the recovery phase of this large storm using a 3-D diffusion simulation. By quantitatively comparing the observed and simulated electronmore » evolution, we found that chorus plays a critical role in accelerating electrons up to several MeV near the developing peak location and produces characteristic flat-top pitch angle distributions. By only including radial diffusion, the simulation underestimates the observed electron acceleration, while radial diffusion plays an important role in redistributing electrons and potentially accelerates them to even higher energies. Moreover, plasmaspheric hiss is found to provide efficient pitch angle scattering losses for hundreds of keV electrons, while its scattering effect on > 1 MeV electrons is relatively slow. Although an additional loss process is required to fully explain the overestimated electron fluxes at multi-MeV, the combined physical processes of radial diffusion and pitch angle and energy diffusion by chorus and hiss reproduce the observed electron dynamics remarkably well, suggesting that quasi-linear diffusion theory is reasonable to evaluate radiation belt electron dynamics during this big storm.« less

Method and apparatus for physical separation of different sized nanostructures

DOEpatents

Roberts, Christopher B.; Saunders, Steven R.

2012-07-10

The present application provides apparatuses and methods for the size-selective fractionation of ligand-capped nanoparticles that utilizes the tunable thermophysical properties of gas-expanded liquids. The nanoparticle size separation processes are based on the controlled reduction of the solvent strength of an organic phase nanoparticle dispersion through increases in concentration of the antisolvent gas, such as CO.sub.2, via pressurization. The method of nanomaterial separation contains preparing a vessel having a solvent and dispersed nanoparticles, pressurizing the chamber with a gaseous antisolvent, and causing a first amount of the nanoparticles to precipitate, transporting the solution to a second vessel, pressurizing the second vessel with the gaseous antisolvent and causing further nanoparticles to separate from the solution.

Aerodynamic distortion propagation calculation in application of high-speed target detection by laser

NASA Astrophysics Data System (ADS)

Zheng, Yonghui; Sun, Huayan; Zhao, Yanzhong; Chen, Jianbiao

2015-10-01

Active laser detection technique has a broad application prospect in antimissile and air defense, however the aerodynamic flow field around the planes and missiles cause serious distortion effect on the detecting laser beams. There are many computational fluid dynamics(CFD) codes that can predict the air density distribution and also the density fluctuations of the flow field, it's necessary for physical optics to be used to predict the distortion properties after propagation through the complex process. Aiming at the physical process of laser propagation in "Cat-eye" lenses and aerodynamic flow field for twice, distortion propagation calculation method is researched in this paper. In the minds of dividing the whole process into two parts, and tread the aero-optical optical path difference as a phase distortion, the incidence and reflection process are calculated using Collins formula and angular spectrum diffraction theory respectively. In addition, turbulent performance of the aerodynamic flow field is estimated according to the electromagnetic propagation theory through a random medium, the rms optical path difference and Strehl ratio of the turbulent optical distortion are obtained. Finally, Computational fluid mechanics and aero-optical distortion properties of the detecting laser beams are calculated with the hemisphere-on-cylinder turret as an example, calculation results are showed and analysed.

Copper accumulation in vineyard soils: Rhizosphere processes and agronomic practices to limit its toxicity.

PubMed

Brunetto, Gustavo; Bastos de Melo, George Wellington; Terzano, Roberto; Del Buono, Daniele; Astolfi, Stefania; Tomasi, Nicola; Pii, Youry; Mimmo, Tanja; Cesco, Stefano

2016-11-01

Viticulture represents an important agricultural practice in many countries worldwide. Yet, the continuous use of fungicides has caused copper (Cu) accumulation in soils, which represent a major environmental and toxicological concern. Despite being an important micronutrient, Cu can be a potential toxicant at high concentrations since it may cause morphological, anatomical and physiological changes in plants, decreasing both food productivity and quality. Rhizosphere processes can, however, actively control the uptake and translocation of Cu in plants. In particular, root exudates affecting the chemical, physical and biological characteristics of the rhizosphere, might reduce the availability of Cu in the soil and hence its absorption. In addition, this review will aim at discussing the advantages and disadvantages of agronomic practices, such as liming, the use of pesticides, the application of organic matter, biochar and coal fly ashes, the inoculation with bacteria and/or mycorrhizal fungi and the intercropping, in alleviating Cu toxicity symptoms. Copyright © 2016 Elsevier Ltd. All rights reserved.

Emerging Roles of microRNAs in Ischemic Stroke: As Possible Therapeutic Agents

PubMed Central

Khoshnam, Seyed Esmaeil; Winlow, William; Farbood, Yaghoob; Moghaddam, Hadi Fathi; Farzaneh, Maryam

2017-01-01

Stroke is one of the leading causes of death and physical disability worldwide. The consequences of stroke injuries are profound and persistent, causing in considerable burden to both the individual patient and society. Current treatments for ischemic stroke injuries have proved inadequate, partly owing to an incomplete understanding of the cellular and molecular changes that occur following ischemic stroke. MicroRNAs (miRNA) are endogenously expressed RNA molecules that function to inhibit mRNA translation and have key roles in the pathophysiological processes contributing to ischemic stroke injuries. Potential therapeutic areas to compensate these pathogenic processes include promoting angiogenesis, neurogenesis and neuroprotection. Several miRNAs, and their target genes, are recognized to be involved in these recoveries and repair mechanisms. The capacity of miRNAs to simultaneously regulate several target genes underlies their unique importance in ischemic stroke therapeutics. In this Review, we focus on the role of miRNAs as potential diagnostic and prognostic biomarkers, as well as promising therapeutic agents in cerebral ischemic stroke. PMID:28480877

Characteristics of Extreme Geoelectric Fields and Their Possible Causes: Localized Peak Enhancements

NASA Astrophysics Data System (ADS)

Pulkkinen, A. A.; Ngwira, C. M.; Bernabeu, E.; Eichner, J.; Viljanen, A.; Crowley, G.

2015-12-01

One of the major challenges pertaining to extreme geomagnetic storms is to understand the basic processes associated with the development of dynamic magnetosphere-ionosphere currents, which generate large induced surface geoelectric fields. Previous studies point out the existence of localized peak geoelectric field enhancements during extreme storms. We examined induced global geoelectric fields derived from ground-based magnetometer recordings for 12 extreme geomagnetic storms between the years 1982--2005. However for the present study, an in-depth analysis was performed for two important extreme storms, October 29, 2003 and March 13, 1989. The primary purpose of this paper is to provide further evidence on the existence of localized peak geoelectric field enhancements, and to show that the structure of the geoelectric field during these localized extremes at single sites can differ greatly from globally and regionally averaged fields. Although the physical processes that govern the development of these localized extremes are still not clear, we discuss some possible causes.

Televised relational and physical aggression and children's hostile intent attributions.

PubMed

Martins, Nicole

2013-12-01

An experiment was conducted with 150 children (mean age=10.1years) in third to fifth grades to test whether exposure to different forms of aggression in the media affected hostile attributional biases in response to different forms of provocation scenarios. Children were randomly assigned to watch a clip containing physical aggression, relational aggression, or no aggression. After exposure, children were asked to respond to a series of written provocation scenarios where a character caused some form of harm (instrumental or relational) to a target person, but the intent of the provocateur was ambiguous. Results revealed that exposure to relationally aggressive portrayals resulted in a hostile attributional bias in response to relational scenarios, whereas exposure to portrayals of physical aggression was associated with a hostile attributional bias in response to instrumental scenarios. Moreover, these biases were shown to be specific to the exposure condition (physical or relational) and not simply associated with exposure to aggression in general. The findings are discussed in terms of the general aggression model and children's social information processing. Copyright © 2013 Elsevier Inc. All rights reserved.

Causal explanations for class inequality in health--an empirical analysis.

PubMed

Lundberg, O

1991-01-01

One of the most important issues for research on social class inequalities in health are the causes behind such differences. So far, the debate on class inequalities in health has mainly been centred around hypotheses on artefactual and selectional processes. Although most contributors to this branch of research have argued in favour of causal explanations, these have gained very little systematic scrutiny. In this article, several possible causal factors are singled out for empirical testing. The effect of these factors on class differences in physical and mental illness is studied by means of logit regressions. On the basis of these analyses, it is shown that physical working conditions are the prime source of class inequality in physical illness, although economic hardship during upbringing and health related behaviours also contribute. For class inequality in mental illness these three factors plus weak social network are important. In sum, a large part of the class differences in physical as well as mental illness can be understood as a result of systematic differences between classes in living conditions, primarily differences in working conditions.

Physical and Chemical Properties of Coal Bottom Ash (CBA) from Tanjung Bin Power Plant

NASA Astrophysics Data System (ADS)

Izzati Raihan Ramzi, Nurul; Shahidan, Shahiron; Zulkhairi Maarof, Mohamad; Ali, Noorwirdawati

2016-11-01

The objective of this study is to determine the physical and chemical characteristics of Coal Bottom Ash (CBA) obtained from Tanjung Bin Power Plant Station and compare them with the characteristics of natural river sand (as a replacement of fine aggregates). Bottom ash is the by-product of coal combustion during the electricity generating process. However, excess bottom ash production due to the high production of electricity in Malaysia has caused several environmental problems. Therefore, several tests have been conducted in order to determine the physical and chemical properties of bottom ash such as specific gravity, density, particle size distribution, Scanning Electron Microscopic (SEM) and X- Ray Fluorescence (XRF) in the attempt to produce sustainable material from waste. The results indicated that the natural fine aggregate and coal bottom ash have very different physical and chemical properties. Bottom ash was classified as Class C ash. The porous structure, angular and rough texture of bottom ash affected its specific gravity and particle density. From the tests, it was found that bottom ash is recommended to be used in concrete as a replacement for fine aggregates.

Psychiatric and Physical Morbidity Effects of Dementia Caregiving: Prevalence, Correlates, and Causes.

ERIC Educational Resources Information Center

Schultz, Richard; And Others

1995-01-01

Assesses the prevalence and magnitude of psychiatric and physical morbidity effects among dementia caregivers, identifies individual and contextual correlates of reported health effects and their underlying causes, and examines the policy relevance of observed findings. (JPS)

Examining age-related shared variance between face cognition, vision, and self-reported physical health: a test of the common cause hypothesis for social cognition

PubMed Central

Olderbak, Sally; Hildebrandt, Andrea; Wilhelm, Oliver

2015-01-01

The shared decline in cognitive abilities, sensory functions (e.g., vision and hearing), and physical health with increasing age is well documented with some research attributing this shared age-related decline to a single common cause (e.g., aging brain). We evaluate the extent to which the common cause hypothesis predicts associations between vision and physical health with social cognition abilities specifically face perception and face memory. Based on a sample of 443 adults (17–88 years old), we test a series of structural equation models, including Multiple Indicator Multiple Cause (MIMIC) models, and estimate the extent to which vision and self-reported physical health are related to face perception and face memory through a common factor, before and after controlling for their fluid cognitive component and the linear effects of age. Results suggest significant shared variance amongst these constructs, with a common factor explaining some, but not all, of the shared age-related variance. Also, we found that the relations of face perception, but not face memory, with vision and physical health could be completely explained by fluid cognition. Overall, results suggest that a single common cause explains most, but not all age-related shared variance with domain specific aging mechanisms evident. PMID:26321998

Temporal Genetic Modifications after Controlled Cortical Impact—Understanding Traumatic Brain Injury through a Systematic Network Approach

PubMed Central

Wong, Yung-Hao; Wu, Chia-Chou; Wu, John Chung-Che; Lai, Hsien-Yong; Chen, Kai-Yun; Jheng, Bo-Ren; Chen, Mien-Cheng; Chang, Tzu-Hao; Chen, Bor-Sen

2016-01-01

Traumatic brain injury (TBI) is a primary injury caused by external physical force and also a secondary injury caused by biological processes such as metabolic, cellular, and other molecular events that eventually lead to brain cell death, tissue and nerve damage, and atrophy. It is a common disease process (as opposed to an event) that causes disabilities and high death rates. In order to treat all the repercussions of this injury, treatment becomes increasingly complex and difficult throughout the evolution of a TBI. Using high-throughput microarray data, we developed a systems biology approach to explore potential molecular mechanisms at four time points post-TBI (4, 8, 24, and 72 h), using a controlled cortical impact (CCI) model. We identified 27, 50, 48, and 59 significant proteins as network biomarkers at these four time points, respectively. We present their network structures to illustrate the protein–protein interactions (PPIs). We also identified UBC (Ubiquitin C), SUMO1, CDKN1A (cyclindependent kinase inhibitor 1A), and MYC as the core network biomarkers at the four time points, respectively. Using the functional analytical tool MetaCore™, we explored regulatory mechanisms and biological processes and conducted a statistical analysis of the four networks. The analytical results support some recent findings regarding TBI and provide additional guidance and directions for future research. PMID:26861311

Physical fitness and perceived psychological pressure at work: 30-year ischemic heart disease and all-cause mortality in the Copenhagen Male Study.

PubMed

Holtermann, Andreas; Mortensen, Ole Steen; Burr, Hermann; Søgaard, Karen; Gyntelberg, Finn; Suadicani, Poul

2011-07-01

Investigate if workers with low physical fitness have an increased risk of ischemic heart disease (IHD) mortality from regular psychological work pressure. Thirty-year follow-up of 5249 middle-aged men without cardiovascular disease. Men perceiving regular psychological work pressure had no higher risk of IHD mortality than those who did not. Both among men perceiving regular and rare psychological work pressure, the physically fit had a reduced risk of IHD mortality referencing men with low physical fitness. For all-cause mortality, a stronger inverse association was found among men perceiving regular compared to rare psychological pressure at work. Physical fitness is equally important for the risk of IHD mortality among men experiencing regular and rare psychological pressure at work, but stronger associated to risk of all-cause mortality among men experiencing regular psychological pressure at work.

Range pattern matching with layer operations and continuous refinements

NASA Astrophysics Data System (ADS)

Tseng, I.-Lun; Lee, Zhao Chuan; Li, Yongfu; Perez, Valerio; Tripathi, Vikas; Ong, Jonathan Yoong Seang

2018-03-01

At advanced and mainstream process nodes (e.g., 7nm, 14nm, 22nm, and 55nm process nodes), lithography hotspots can exist in layouts of integrated circuits even if the layouts pass design rule checking (DRC). Existence of lithography hotspots in a layout can cause manufacturability issues, which can result in yield losses of manufactured integrated circuits. In order to detect lithography hotspots existing in physical layouts, pattern matching (PM) algorithms and commercial PM tools have been developed. However, there are still needs to use DRC tools to perform PM operations. In this paper, we propose a PM synthesis methodology, which uses a continuous refinement technique, for the automatic synthesis of a given lithography hotspot pattern into a DRC deck, which consists of layer operation commands, so that an equivalent PM operation can be performed by executing the synthesized deck with the use of a DRC tool. Note that the proposed methodology can deal with not only exact patterns, but also range patterns. Also, lithography hotspot patterns containing multiple layers can be processed. Experimental results show that the proposed methodology can accurately and efficiently detect lithography hotspots in physical layouts.

Amyloid fibrils: formation, replication, and physics behind them

NASA Astrophysics Data System (ADS)

Saric, Andela

The assembly of normally soluble proteins into long fibrils, known as amyloids, is associated with a range of pathologies, including Alzheimer's and Parkinson's diseases. A large number of structurally unrelated proteins form this type of fibrils, and we are in a pursuit of physical principles that underlie the amyloid formation and propagation. We show that small disorders oligomers, which are increasingly believed to be the prime cause for cellular toxicity, serve as nucleation centers for the fibril formation. We then relate experimentally measurable kinetic descriptors of amyloid aggregation to the microscopic mechanisms of the process. Once formed, amyloid fibrils can catalyse the formation of new oligomers and fibrils in a process that resembles self-replication. By combining simulations with biosensing and kinetic measurements of the aggregation of Alzheimer's A β peptide, we propose a mechanistic explanation for the self-replication of protein fibrils, and discuss its thermodynamic signature. Finally, we consider the design of possible inhibitors of the fibril self-replication process. Mechanistic understandings provided here not only have implications for future efforts to control pathological protein aggregation, but are also of interest for the rational assembly of bionanomaterials, where achieving and controlling self-replication is one of the unfulfilled goals.

Accelerometer-Determined Physical Activity and Mortality in a National Prospective Cohort Study: Considerations by Hearing Sensitivity.

PubMed

Loprinzi, Paul D

2015-12-01

Previous work demonstrates that hearing impairment and physical inactivity are associated with premature all-cause mortality. The purpose of this study was to discern whether increased physical activity among those with hearing impairment can produce survival benefits. Data from the 2003-2006 National Health and Nutrition Examination Survey were used, with follow-up through 2011. Physical activity was objectively measured over 7 days via accelerometry. Hearing sensitivity was objectively measured using a modified Hughson Westlake procedure. Among the 1,482 participants, 152 died during the follow-up period (10.26%, unweighted); the unweighted median follow-up period was 89 months (interquartile range = 74-98 months). For those with normal hearing and after adjustments, for every 60-min increase in physical activity, adults had a 19% (HR [Hazard Ratio] = 0.81; 95% confidence interval [CI] [0.48-1.35]; p = .40) reduced risk of all-cause mortality; however, this association was not statistically significant. In a similar manner, physical activity was not associated with all-cause mortality among those with mild hearing loss (HR = 0.76; 95% CI [0.51-1.13]; p = .17). However, after adjustments, and for every 60-min increase in physical activity for those with moderate or greater hearing loss, there was a 20% (HR = 0.20; 95% CI [0.67-0.95]; p = .01) reduced risk of all-cause mortality. Physical activity may help to prolong survival among those with greater hearing impairment.

Strategies for optimizing military physical readiness and preventing musculoskeletal injuries in the 21st century.

PubMed

Nindl, Bradley C; Williams, Thomas J; Deuster, Patricia A; Butler, Nikki L; Jones, Bruce H

2013-01-01

With downsizing of the military services and significant budget cuts, it will be more important than ever to optimize the health and performance of individual service members. Musculoskeletal injuries (MSIs) represent a major threat to the health and fitness of Soldiers and other service members that degrade our nation's ability to project military power. This affects both financial (such as the economic burden from medical, healthcare, and disability costs) and human manpower resources (Soldiers medically unable to optimally perform their duties and to deploy). For example, in 2012, MSIs represented the leading cause of medical care visits across the military services resulting in almost 2,200,000 medical encounters. They also result in more disability discharges than any other health condition. Nonbattle injuries (NBIs) have caused more medical evacuations (34%) from recent theaters of operation than any other cause including combat injuries. Physical training and sports are the main cause of these NBIs. The majority (56%) of these injuries are the direct result of physical training. Higher levels of physical fitness protect against such injuries; however, more physical training to improve fitness also causes higher injury rates. Thus, military physical training programs must balance the need for fitness with the risks of injuries. The Army has launched several initiatives that may potentially improve military physical readiness and reduce injuries. These include the US Army Training and Doctrine Command's Baseline Soldier Physical Readiness Requirements and Gender Neutral Physical Performance Standards studies, as well as the reimplementation of the Master Fitness Trainer program and the Army Medical Command's Soldier Medical Readiness and Performance Triad Campaigns. It is imperative for military leaders to understand that military physical readiness can be enhanced at the same time that MSIs are prevented. A strategic paradigm shift in the military's approach to physical readiness policies is needed to avoid further degradation of warfighting capability in an era of austerity. We believe this can be best accomplished through leveraging scientific, evidence-based best practices by Army senior leadership which supports, prioritizes, and implements innovative, synchronized, and integrated human performance optimization/injury prevention policy changes.

Burden of physical inactivity and hospitalization costs due to chronic diseases

PubMed Central

Bielemann, Renata Moraes; da Silva, Bruna Gonçalves Cordeiro; Coll, Carolina de Vargas Nunes; Xavier, Mariana Otero; da Silva, Shana Ginar

2015-01-01

OBJECTIVE To evaluate the physical inactivity-related inpatient costs of chronic non-communicable diseases. METHODS This study used data from 2013, from Brazilian Unified Health System, regarding inpatient numbers and costs due to malignant colon and breast neoplasms, cerebrovascular diseases, ischemic heart diseases, hypertension, diabetes, and osteoporosis. In order to calculate the share physical inactivity represents in that, the physical inactivity-related risks, which apply to each disease, were considered, and physical inactivity prevalence during leisure activities was obtained from Pesquisa Nacional por Amostra de Domicílio (Brazil’s National Household Sample Survey). The analysis was stratified by genders and residing country regions of subjects who were 40 years or older. The physical inactivity-related hospitalization cost regarding each cause was multiplied by the respective share it regarded to. RESULTS In 2013, 974,641 patients were admitted due to seven different causes in Brazil, which represented a high cost. South region was found to have the highest patient admission rate in most studied causes. The highest prevalences for physical inactivity were observed in North and Northeast regions. The highest inactivity-related share in men was found for osteoporosis in all regions (≈ 35.0%), whereas diabetes was found to have a higher share regarding inactivity in women (33.0% to 37.0% variation in the regions). Ischemic heart diseases accounted for the highest total costs that could be linked to physical inactivity in all regions and for both genders, being followed by cerebrovascular diseases. Approximately 15.0% of inpatient costs from Brazilian Unified Health System were connected to physical inactivity. CONCLUSIONS Physical inactivity significantly impacts the number of patient admissions due to the evaluated causes and through their resulting costs, with different genders and country regions representing different shares. PMID:26487291

Burden of physical inactivity and hospitalization costs due to chronic diseases.

PubMed

Bielemann, Renata Moraes; Silva, Bruna Gonçalves Cordeiro da; Coll, Carolina de Vargas Nunes; Xavier, Mariana Otero; Silva, Shana Ginar da

2015-01-01

To evaluate the physical inactivity-related inpatient costs of chronic non-communicable diseases. This study used data from 2013, from Brazilian Unified Health System, regarding inpatient numbers and costs due to malignant colon and breast neoplasms, cerebrovascular diseases, ischemic heart diseases, hypertension, diabetes, and osteoporosis. In order to calculate the share physical inactivity represents in that, the physical inactivity-related risks, which apply to each disease, were considered, and physical inactivity prevalence during leisure activities was obtained from Pesquisa Nacional por Amostra de Domicílio(Brazil's National Household Sample Survey). The analysis was stratified by genders and residing country regions of subjects who were 40 years or older. The physical inactivity-related hospitalization cost regarding each cause was multiplied by the respective share it regarded to. In 2013, 974,641 patients were admitted due to seven different causes in Brazil, which represented a high cost. South region was found to have the highest patient admission rate in most studied causes. The highest prevalences for physical inactivity were observed in North and Northeast regions. The highest inactivity-related share in men was found for osteoporosis in all regions (≈ 35.0%), whereas diabetes was found to have a higher share regarding inactivity in women (33.0% to 37.0% variation in the regions). Ischemic heart diseases accounted for the highest total costs that could be linked to physical inactivity in all regions and for both genders, being followed by cerebrovascular diseases. Approximately 15.0% of inpatient costs from Brazilian Unified Health System were connected to physical inactivity. Physical inactivity significantly impacts the number of patient admissions due to the evaluated causes and through their resulting costs, with different genders and country regions representing different shares.

Understanding soil erosion impacts in temperate agroecosystems: bridging the gap between geomorphology and soil ecology

NASA Astrophysics Data System (ADS)

Baxter, C.; Rowan, J. S.; McKenzie, B. M.; Neilson, R.

2013-04-01

Soil is a key asset of natural capital, providing a myriad of goods and ecosystem services that sustain life through regulating, supporting and provisioning roles, delivered by chemical, physical and biological processes. One of the greatest threats to soil is accelerated erosion, which raises a natural process to unsustainable levels, and has downstream consequences (e.g. economic, environmental and social). Global intensification of agroecosystems is a major cause of soil erosion which, in light of predicted population growth and increased demand for food security, will continue or increase. Elevated erosion and transport is common in agroecosystems and presents a multi-disciplinary problem with direct physical impacts (e.g. soil loss), other less tangible impacts (e.g. loss of ecosystem productivity), and indirect downstream effects that necessitate an integrated approach to effectively address the problem. Climate is also likely to increase susceptibility of soil to erosion. Beyond physical response, the consequences of erosion on soil biota have hitherto been ignored, yet biota play a fundamental role in ecosystem service provision. To our knowledge few studies have addressed the gap between erosion and consequent impacts on soil biota. Transport and redistribution of soil biota by erosion is poorly understood, as is the concomitant impact on biodiversity and ability of soil to deliver the necessary range of ecosystem services to maintain function. To investigate impacts of erosion on soil biota a two-fold research approach is suggested. Physical processes involved in redistribution should be characterised and rates of transport and redistribution quantified. Similarly, cumulative and long-term impacts of biota erosion should be considered. Understanding these fundamental aspects will provide a basis upon which mitigation strategies can be considered.

Tweedie convergence: a mathematical basis for Taylor's power law, 1/f noise, and multifractality.

PubMed

Kendal, Wayne S; Jørgensen, Bent

2011-12-01

Plants and animals of a given species tend to cluster within their habitats in accordance with a power function between their mean density and the variance. This relationship, Taylor's power law, has been variously explained by ecologists in terms of animal behavior, interspecies interactions, demographic effects, etc., all without consensus. Taylor's law also manifests within a wide range of other biological and physical processes, sometimes being referred to as fluctuation scaling and attributed to effects of the second law of thermodynamics. 1/f noise refers to power spectra that have an approximately inverse dependence on frequency. Like Taylor's law these spectra manifest from a wide range of biological and physical processes, without general agreement as to cause. One contemporary paradigm for 1/f noise has been based on the physics of self-organized criticality. We show here that Taylor's law (when derived from sequential data using the method of expanding bins) implies 1/f noise, and that both phenomena can be explained by a central limit-like effect that establishes the class of Tweedie exponential dispersion models as foci for this convergence. These Tweedie models are probabilistic models characterized by closure under additive and reproductive convolution as well as under scale transformation, and consequently manifest a variance to mean power function. We provide examples of Taylor's law, 1/f noise, and multifractality within the eigenvalue deviations of the Gaussian unitary and orthogonal ensembles, and show that these deviations conform to the Tweedie compound Poisson distribution. The Tweedie convergence theorem provides a unified mathematical explanation for the origin of Taylor's law and 1/f noise applicable to a wide range of biological, physical, and mathematical processes, as well as to multifractality.

46 CFR 5.201 - Voluntary deposits in event of mental or physical incompetence.

Code of Federal Regulations, 2013 CFR

2013-10-01

... incompetence of a holder of a credential or endorsement is caused by use of or addiction to dangerous drugs, a... mental or physical incompetence of a holder of a credential or endorsement is caused by use or addiction...

46 CFR 5.201 - Voluntary deposits in event of mental or physical incompetence.

Code of Federal Regulations, 2014 CFR

2014-10-01

... incompetence of a holder of a credential or endorsement is caused by use of or addiction to dangerous drugs, a... mental or physical incompetence of a holder of a credential or endorsement is caused by use or addiction...

46 CFR 5.201 - Voluntary deposits in event of mental or physical incompetence.

Code of Federal Regulations, 2010 CFR

2010-10-01

... incompetence of a holder of a credential or endorsement is caused by use of or addiction to dangerous drugs, a... mental or physical incompetence of a holder of a credential or endorsement is caused by use or addiction...

46 CFR 5.201 - Voluntary deposits in event of mental or physical incompetence.

Code of Federal Regulations, 2011 CFR

2011-10-01

... incompetence of a holder of a credential or endorsement is caused by use of or addiction to dangerous drugs, a... mental or physical incompetence of a holder of a credential or endorsement is caused by use or addiction...

46 CFR 5.201 - Voluntary deposits in event of mental or physical incompetence.

Code of Federal Regulations, 2012 CFR

2012-10-01

... incompetence of a holder of a credential or endorsement is caused by use of or addiction to dangerous drugs, a... mental or physical incompetence of a holder of a credential or endorsement is caused by use or addiction...

Geomorphic processes active in the Southwestern Louisiana Canal, Lafourche Parish, Louisiana

NASA Technical Reports Server (NTRS)

Doiron, L. N.; Whitehurst, C. A.

1974-01-01

The geomorphological changes causing the destruction of the banks of the Southwestern Louisiana Canal are studied by means of field work, laboratory analyses, and infrared color imagery interpretation. Turbulence and flow patterns are mapped, and related to erosion and sediment deposition processes. The accelerated erosion rate of the last decade is discussed, with two causative factors cited: (1) development of faster boats, increasing bank and bottom erosion, and (2) a subsequently larger tidal influx, with greater erosive ability. The physical properties of the canal bank materials are also analyzed. It is concluded that channel erosion progressively increases, with no indications of stabilization, until they merge with other waterways and become indistinguishable from natural water bodies.

Physical mechanism of coherent acoustic phonons generation and detection in GaAs semiconductor

NASA Astrophysics Data System (ADS)

Babilotte, P.; Morozov, E.; Ruello, P.; Mounier, D.; Edely, M.; Breteau, J.-M.; Bulou, A.; Gusev, V.

2007-12-01

We first describe the picosecond acoustic interferometry study of GaAs with two-colors pump-probe laser pulses. The dependence of the generation process on the pump wavelength and the detection process on the probe wavelength both can cause the shift in the phase of the Brillouin signal. Secondly, in order to distinguish the short high frequency wideband acoustic pulse from low frequency Brillouin contribution, we accomplished experiments with (100)GaAs semiconductor coated by a transparent and photoelastically inactive thin film, serving a delay line for the acoustic pulse. Even with highly penetrating pump light (approx 680nm), short acoustic disturbances of approx 7ps of duration have been registered.

KSC-98pc1133

NASA Image and Video Library

1998-09-18

KENNEDY SPACE CENTER, FLA. -- The Spartan solar-observing deployable spacecraft is placed inside the payload canister in the Multi-Payload Processing Facility at KSC. Spartan is one of the payloads for the STS-95 mission, scheduled to launch Oct. 29. Spartan is a solar physics spacecraft designed to perform remote sensing of the hot outer layers of the sun's atmosphere or corona. The objective of the observations is to investigate the mechanisms causing the heating of the solar corona and the acceleration of the solar wind which originates in the corona. Other research payloads include the Hubble Space Telescope Orbital Systems Test Platform, the International Extreme Ultraviolet Hitchhiker, and the SPACEHAB single module with experiments on space flight and the aging process

KSC-98pc1132

NASA Image and Video Library

1998-09-18

KENNEDY SPACE CENTER, FLA. -- The Spartan solar-observing deployable spacecraft is suspended above the payload canister in the Multi-Payload Processing Facility at KSC. Spartan is one of the payloads for the STS-95 mission, scheduled to launch Oct. 29. Spartan is a solar physics spacecraft designed to perform remote sensing of the hot outer layers of the sun's atmosphere or corona. The objective of the observations is to investigate the mechanisms causing the heating of the solar corona and the acceleration of the solar wind which originates in the corona. Other research payloads include the Hubble Space Telescope Orbital Systems Test Platform, the International Extreme Ultraviolet Hitchhiker, and the SPACEHAB single module with experiments on space flight and the aging process

Composite substrate for bipolar electrodes

DOEpatents

Tekkanat, B.; Bolstad, J.J.

1992-12-22

Substrates for electrode systems, particularly those to be used for bipolar electrodes in zinc-bromine batteries, are disclosed. The substrates preferably include carbon-black as a conductive filler in a polymeric matrix, with reinforcing materials such as glass fibers. Warpage of the zinc-bromine electrodes which was experienced in the prior art and which was believed to be caused by physical expansion of the electrodes due to bromine absorption by the carbon-black, is substantially eliminated when new substrate fabrication techniques are employed. In the present invention, substrates are prepared using a lamination process known as glass mat reinforced thermoplastics technology or, in an alternate embodiment, the substrate is made using a slurry process. 4 figs.

Abiotic and biotic degradation of oxo-biodegradable plastic bags by Pleurotus ostreatus.

PubMed

da Luz, José Maria Rodrigues; Paes, Sirlaine Albino; Bazzolli, Denise Mara Soares; Tótola, Marcos Rogério; Demuner, Antônio Jacinto; Kasuya, Maria Catarina Megumi

2014-01-01

In this study, we evaluated the growth of Pleurotus ostreatus PLO6 using oxo-biodegradable plastics as a carbon and energy source. Oxo-biodegradable polymers contain pro-oxidants that accelerate their physical and biological degradation. These polymers were developed to decrease the accumulation of plastic waste in landfills. To study the degradation of the plastic polymers, oxo-biodegradable plastic bags were exposed to sunlight for up to 120 days, and fragments of these bags were used as substrates for P. ostreatus. We observed that physical treatment alone was not sufficient to initiate degradation. Instead, mechanical modifications and reduced titanium oxide (TiO2) concentrations caused by sunlight exposure triggered microbial degradation. The low specificity of lignocellulolytic enzymes and presence of endomycotic nitrogen-fixing microorganisms were also contributing factors in this process.

Presence of Li Clusters in Molten LiCl-Li

PubMed Central

Merwin, Augustus; Phillips, William C.; Williamson, Mark A.; Willit, James L.; Motsegood, Perry N.; Chidambaram, Dev

2016-01-01

Molten mixtures of lithium chloride and metallic lithium are of significant interest in various metal oxide reduction processes. These solutions have been reported to exhibit seemingly anomalous physical characteristics that lack a comprehensive explanation. In the current work, the physical chemistry of molten solutions of lithium chloride and metallic lithium, with and without lithium oxide, was investigated using in situ Raman spectroscopy. The Raman spectra obtained from these solutions were in agreement with the previously reported spectrum of the lithium cluster, Li8. This observation is indicative of a nanofluid type colloidal suspension of Li8 in a molten salt matrix. It is suggested that the formation and suspension of lithium clusters in lithium chloride is the cause of various phenomena exhibited by these solutions that were previously unexplainable. PMID:27145895

Effect of physical inactivity on major noncommunicable diseases and life expectancy in Brazil.

PubMed

de Rezende, Leandro Fornias Machado; Rabacow, Fabiana Maluf; Viscondi, Juliana Yukari Kodaira; Luiz, Olinda do Carmo; Matsudo, Victor Keihan Rodrigues; Lee, I-Min

2015-03-01

In Brazil, one-fifth of the population reports not doing any physical activity. This study aimed to assess the impact of physical inactivity on major noncommunicable diseases (NCDs), all-cause mortality and life expectancy in Brazil, by region and sociodemographic profile. We estimated the population attributable fraction (PAF) for physical inactivity associated with coronary heart disease, type 2 diabetes, breast cancer, colon cancer, and all-cause mortality. To calculate the PAF, we used the physical inactivity prevalence from the 2008 Brazilian Household Survey and relative risk data in the literature. In Brazil, physical inactivity is attributable to 3% to 5% of all major NCDs and 5.31% of all-cause mortality, ranging from 5.82% in the southeastern region to 2.83% in the southern region. Eliminating physical inactivity would increase the life expectancy by an average of 0.31 years. This reduction would affect mainly individuals with ≥ 15 years of schooling, male, Asian, elderly, residing in an urban area and earning ≥ 2 times the national minimum wage. In Brazil, physical inactivity has a major impact on NCDs and mortality, principally in the southeastern and central-west regions. Public policies and interventions promoting physical activity will significantly improve the health of the population.

Quality evaluation of probiotic capsule prepared from alginate, carrageenan and tofu waste flour based on bacterial activity and organoleptic test

NASA Astrophysics Data System (ADS)

Muhardina, V.; Ermaya, D.; Aisyah, Y.; Haryani, S.

2018-02-01

Probiotic capsule is an innovation in functional food sector. It is used to preserve the living cells of probiotic bacteria during processing and storage. In this research, the improvement of probiotic viability is studied by using two kinds of encapsulating biomaterials and different concentration of tofu waste flour. Extrusion is selected method for encapsulation process. The purpose of this study is to examine the quality of probiotic capsule by evaluating the lactic acid bacteria performance and its physical characteristic. The article provides the data of probiotic bacteria activity related to their living cells present in capsule, activity in fermentation media compare to uncapsulated bacteria, and panelists’ preferences of capsule’s physical properties. The data is analyzed statistically by using ANOVA. The result shows that variables in this study affect the number of bacteria, their metabolic activity in producing acid during fermentation, and physical appearance of the capsule. Combination of alginate and tofu waste flour allows the multiplication of bacteria to a high number, and forms elastic, yellow and cloudy capsule, while with carrageenan, it causes the growth of a few numbers of bacteria which affects to a moderate pH and produces elastic, creamy and transparent capsule.

On the Concept of Information and Its Role in Nature

NASA Astrophysics Data System (ADS)

Roederer, Juan G.

2003-03-01

In this article we address some fundamental questions concerning information: Can the existing laws of physics adequately deal with the most striking property of information, namely to cause specific changes in the structure and energy flows of a complex system, without the information in itself representing fields, forces or energy in any of their characteristic forms? Or is information irreducible to the laws of physics and chemistry? Are information and complexity related concepts? Does the Universe, in its evolution, constantly generate new information? Or are information and information-processing exclusive attributes of living systems, related to the very definition of life? If that were the case, what happens with the physical meanings of entropy in statistical mechanics or wave function in quantum mechanics? How many distinct classes of information and information processing do exist in the biological world? How does information appear in Darwinian evolution? Does the human brain have unique properties or capabilities in terms of information processing? In what ways does information processing bring about human self-consciousness? We shall introduce the meaning of "information" in a way that is detached from human technological systems and related algorithms and semantics, and that is not based on any mathematical formula. To accomplish this we turn to the concept of interaction as the basic departing point, and identify two fundamentally different classes, with information and information-processing appearing as the key discriminator: force-field driven interactions between elementary particles and ensembles of particles in the macroscopic physical domain, and information-based interactions between certain kinds of complex systems that form the biological domain. We shall show that in an abiotic world, information plays no role; physical interactions just happen, they are driven by energy exchange between the interacting parts and do not require any operations of information processing. Information only enters the non-living physical world when a living thing interacts with it-and when a scientist extracts information through observation and measurement. But for living organisms, information is the very essence of their existence: to maintain a long-term state of unstable thermodynamic equilibrium with its surroundings, consistently increase its organization and reproduce, an organism has to rely on information-based interactions in which form or pattern, not energy, is the controlling factor. This latter class comprises biomolecular information processes controlling the metabolism, growth, multiplication and differentiation of cells, and neural information processes controlling animal behavior and intelligence. The only way new information can appear is through the process of biological evolution and, in the short term, through sensory acquisition and the manipulation of images in the nervous system. Non-living informational systems such as books, computers, AI systems and other artifacts, as well as living organisms that are the result of breeding or cloning, are planned by human beings and will not be considered here.

The spirituality of human consciousness: a Catholic evaluation of some current neuro-scientific interpretations.

PubMed

McGoldrick, Terence A

2012-09-01

Catholic theology's traditional understanding of the spiritual nature of the human person begins with the idea of a rational soul and human mind that is made manifest in free will--the spiritual experience of the act of consciousness and cause of all human arts. The rationale for this religion-based idea of personhood is key to understanding ethical dilemmas posed by modern research that applies a more empirical methodology in its interpretations about the cause of human consciousness. Applications of these beliefs about the body/soul composite to the theory of evolution and to discoveries in neuroscience, paleoanthropology, as well as to recent animal intelligence studies, can be interpreted from this religious and philosophical perspective, which argues for the human soul as the unifying cause of the person's unique abilities. Free will and consciousness are at the nexus of the mutual influence of body and soul upon one another in the traditional Catholic view, that argues for a spiritual dimension to personality that is on a par with the physical metabolic processes at play. Therapies that affect consciousness are ethically problematic, because of their implications for free will and human dignity. Studies of resilience, as an example, argue for the greater, albeit limited, role of the soul's conscious choices in healing as opposed to metabolic or physical changes to the brain alone.

Efficiency improvement of technological preparation of power equipment manufacturing

NASA Astrophysics Data System (ADS)

Milukov, I. A.; Rogalev, A. N.; Sokolov, V. P.; Shevchenko, I. V.

2017-11-01

Competitiveness of power equipment primarily depends on speeding-up the development and mastering of new equipment samples and technologies, enhancement of organisation and management of design, manufacturing and operation. Actual political, technological and economic conditions cause the acute need in changing the strategy and tactics of process planning. At that the issues of maintenance of equipment with simultaneous improvement of its efficiency and compatibility to domestically produced components are considering. In order to solve these problems, using the systems of computer-aided process planning for process design at all stages of power equipment life cycle is economically viable. Computer-aided process planning is developed for the purpose of improvement of process planning by using mathematical methods and optimisation of design and management processes on the basis of CALS technologies, which allows for simultaneous process design, process planning organisation and management based on mathematical and physical modelling of interrelated design objects and production system. An integration of computer-aided systems providing the interaction of informative and material processes at all stages of product life cycle is proposed as effective solution to the challenges in new equipment design and process planning.

Predictive Modeling of High-Power Electromagnetic Effects on Electronics (Postprint)

DTIC Science & Technology

2011-09-01

electromagnetic ( HPEM ) pulses at sufficiently high field levels can cause physical damage to electronics. This effect can be explained in terms of the...is caused, an HPEM pulse can still cause data corruption resulting in the system locking up or rebooting itself, an effect we will refer to...language to exercise various functional areas and hence various physical regions of the microcontroller, with the aim of developing fundamental

Passion for a Cause: How It Affects Health and Subjective Well-Being.

PubMed

St-Louis, Ariane C; Carbonneau, Noémie; Vallerand, Robert J

2016-06-01

Using the dualistic model of passion (Vallerand et al., 2003), this research investigated how harmonious passion (HP) or obsessive passion (OP) for a cause can affect volunteers' health and subjective well-being. Three studies with volunteers for local (local emergency crises and community help) and international (humanitarian missions) causes assessed physical and psychological health using cross-sectional and longitudinal designs. Study 1 (N = 108) showed that HP was positively related to satisfaction with one's involvement in the cause and unrelated to physical injuries due to cause involvement. OP was unrelated to satisfaction but positively associated with injuries. Findings were replicated in Study 2 (N = 83). Moreover, self-neglect mediated the positive and negative effects of HP and OP, respectively, on injuries. Study 3 (N = 77) revealed that HP predicted an increase in satisfaction and health over a 3-month mission. OP predicted an increase in physical symptoms and a decrease in health. Furthermore, OP before a mission was positively related to self-neglect that was positively associated with physical symptoms after a mission. OP also positively predicted rumination that was conducive to posttraumatic stress disorder. HP was unrelated to these variables. Findings underscore the role of passion for a cause in predicting intrapersonal outcomes of volunteers. © 2014 Wiley Periodicals, Inc.

Adiposopathy, metabolic syndrome, quantum physics, general relativity, chaos and the Theory of Everything.

PubMed

Bays, Harold

2005-05-01

Excessive fat (adiposity) and dysfunctional fat (adiposopathy) constitute the most common worldwide epidemics of our time -- and perhaps of all time. Ongoing efforts to explain how the micro (adipocyte) and macro (body organ) biologic systems interact through function and dysfunction in promoting Type 2 diabetes mellitus, hypertension and dyslipidemia are not unlike the mechanistic and philosophical thinking processes involved in reconciling the micro (quantum physics) and macro (general relativity) theories in physics. Currently, the term metabolic syndrome refers to a constellation of consequences often associated with excess body fat and is an attempt to unify the associations known to exist between the four fundamental metabolic diseases of obesity, hyperglycemia (including Type 2 diabetes mellitus), hypertension and dyslipidemia. However, the association of adiposity with these metabolic disorders is not absolute and the metabolic syndrome does not describe underlying causality, nor does the metabolic syndrome necessarily reflect any reasonably related pathophysiologic process. Just as with quantum physics, general relativity and the four fundamental forces of the universe, the lack of an adequate unifying theory of micro causality and macro consequence is unsatisfying, and in medicine, impairs the development of agents that may globally improve both obesity and obesity-related metabolic disease. Emerging scientific and clinical evidence strongly supports the novel concept that it is not adiposity alone, but rather it is adiposopathy that is the underlying cause of most cases of Type 2 diabetes mellitus, hypertension and dyslipidemia. Adiposopathy is a plausible Theory of Everything for mankind's greatest metabolic epidemics.

Method for identifying biochemical and chemical reactions and micromechanical processes using nanomechanical and electronic signal identification

DOEpatents

Holzrichter, J.F.; Siekhaus, W.J.

1997-04-15

A scanning probe microscope, such as an atomic force microscope (AFM) or a scanning tunneling microscope (STM), is operated in a stationary mode on a site where an activity of interest occurs to measure and identify characteristic time-varying micromotions caused by biological, chemical, mechanical, electrical, optical, or physical processes. The tip and cantilever assembly of an AFM is used as a micromechanical detector of characteristic micromotions transmitted either directly by a site of interest or indirectly through the surrounding medium. Alternatively, the exponential dependence of the tunneling current on the size of the gap in the STM is used to detect micromechanical movement. The stationary mode of operation can be used to observe dynamic biological processes in real time and in a natural environment, such as polymerase processing of DNA for determining the sequence of a DNA molecule. 6 figs.

Method for identifying biochemical and chemical reactions and micromechanical processes using nanomechanical and electronic signal identification

DOEpatents

Holzrichter, John F.; Siekhaus, Wigbert J.

1997-01-01

A scanning probe microscope, such as an atomic force microscope (AFM) or a scanning tunneling microscope (STM), is operated in a stationary mode on a site where an activity of interest occurs to measure and identify characteristic time-varying micromotions caused by biological, chemical, mechanical, electrical, optical, or physical processes. The tip and cantilever assembly of an AFM is used as a micromechanical detector of characteristic micromotions transmitted either directly by a site of interest or indirectly through the surrounding medium. Alternatively, the exponential dependence of the tunneling current on the size of the gap in the STM is used to detect micromechanical movement. The stationary mode of operation can be used to observe dynamic biological processes in real time and in a natural environment, such as polymerase processing of DNA for determining the sequence of a DNA molecule.

Experimental Replication of an Aeroengine Combustion Instability

NASA Technical Reports Server (NTRS)

Cohen, J. M.; Hibshman, J. R.; Proscia, W.; Rosfjord, T. J.; Wake, B. E.; McVey, J. B.; Lovett, J.; Ondas, M.; DeLaat, J.; Breisacher, K.

2000-01-01

Combustion instabilities in gas turbine engines are most frequently encountered during the late phases of engine development, at which point they are difficult and expensive to fix. The ability to replicate an engine-traceable combustion instability in a laboratory-scale experiment offers the opportunity to economically diagnose the problem (to determine the root cause), and to investigate solutions to the problem, such as active control. The development and validation of active combustion instability control requires that the causal dynamic processes be reproduced in experimental test facilities which can be used as a test bed for control system evaluation. This paper discusses the process through which a laboratory-scale experiment was designed to replicate an instability observed in a developmental engine. The scaling process used physically-based analyses to preserve the relevant geometric, acoustic and thermo-fluid features. The process increases the probability that results achieved in the single-nozzle experiment will be scalable to the engine.

Profiling of back-scattered electrons in opposed magnetic field of a Twin Electron Beam Gun

NASA Astrophysics Data System (ADS)

Sethi, S.; Gupta, Anchal; Dileep Kumar, V.; Mukherjee, Jaya; Gantayet, L. M.

2012-11-01

Electron gun is extensively used in material processing, physical vapour deposition and atomic vapour based laser processes. In these processes where the electron beam is incident on the substrate, a significant fraction of electron beam gets back-scattered from the target surface. The trajectory of this back scattered electron beam depends on the magnetic field in the vicinity. The fraction of back-scattered depends on the atomic number of the target metal and can be as high as ~40% of the incident beam current. These back-scattered electrons can cause undesired hot spots and also affect the overall process. Hence, the study of the trajectory of these back-scattered electrons is important. This paper provides the details of experimentally mapped back-scattered electrons of a 2×20kW Twin Electron Beam Gun (TEBG) in opposed magnetic field i.e. with these guns placed at 180° to each other.

Long-term persistence of solar activity

NASA Technical Reports Server (NTRS)

Ruzmaikin, Alexander; Feynman, Joan; Robinson, Paul

1994-01-01

We examine the question of whether or not the non-periodic variations in solar activity are caused by a white-noise, random process. The Hurst exponent, which characterizes the persistence of a time series, is evaluated for the series of C-14 data for the time interval from about 6000 BC to 1950 AD. We find a constant Hurst exponent, suggesting that solar activity in the frequency range from 100 to 3000 years includes an important continuum component in addition to the well-known periodic variations. The value we calculate, H approximately 0.8, is significantly larger than the value of 0.5 that would correspond to variations produced by a white-noise process. This value is in good agreement with the results for the monthly sunspot data reported elsewhere, indicating that the physics that produces the continuum is a correlated random process and that it is the same type of process over a wide range of time interval lengths.

Optical Theory Improvements to Space Domain Awareness

DTIC Science & Technology

2016-09-15

to other portions of system design. These design components include the Field of View (FoV) of the telescope and the physical dimensions of the system...trying to capture physical characteristics of the object being imaged, and the blurring caused by the atmosphere degrades and limits this capability...experimentally verified in multiple physical experiments [53, 54]. The drawback to these methods is that they assume that the noise caused by the atmosphere is

NASA's Evolutionary Xenon Thruster (NEXT) Power Processing Unit (PPU) Capacitor Failure Root Cause Analysis

NASA Technical Reports Server (NTRS)

Soeder, James F.; Pinero, Luis; Schneidegger, Robert; Dunning, John; Birchenough, Art

2012-01-01

The NASA's Evolutionary Xenon Thruster (NEXT) project is developing an advanced ion propulsion system for future NASA missions for solar system exploration. A critical element of the propulsion system is the Power Processing Unit (PPU) which supplies regulated power to the key components of the thruster. The PPU contains six different power supplies including the beam, discharge, discharge heater, neutralizer, neutralizer heater, and accelerator supplies. The beam supply is the largest and processes up to 93+% of the power. The NEXT PPU had been operated for approximately 200+ hours and has experienced a series of three capacitor failures in the beam supply. The capacitors are in the same, nominally non-critical location the input filter capacitor to a full wave switching inverter. The three failures occurred after about 20, 30, and 135 hours of operation. This paper provides background on the NEXT PPU and the capacitor failures. It discusses the failure investigation approach, the beam supply power switching topology and its operating modes, capacitor characteristics and circuit testing. Finally, it identifies root cause of the failures to be the unusual confluence of circuit switching frequency, the physical layout of the power circuits, and the characteristics of the capacitor.

NASA's Evolutionary Xenon Thruster (NEXT) Power Processing Unit (PPU) Capacitor Failure Root Cause Analysis

NASA Technical Reports Server (NTRS)

Soeder, James F.; Scheidegger, Robert J.; Pinero, Luis R.; Birchenough, Arthur J.; Dunning, John W.

2012-01-01

The NASA s Evolutionary Xenon Thruster (NEXT) project is developing an advanced ion propulsion system for future NASA missions for solar system exploration. A critical element of the propulsion system is the Power Processing Unit (PPU) which supplies regulated power to the key components of the thruster. The PPU contains six different power supplies including the beam, discharge, discharge heater, neutralizer, neutralizer heater, and accelerator supplies. The beam supply is the largest and processes up to 93+% of the power. The NEXT PPU had been operated for approximately 200+ hr and has experienced a series of three capacitor failures in the beam supply. The capacitors are in the same, nominally non-critical location-the input filter capacitor to a full wave switching inverter. The three failures occurred after about 20, 30, and 135 hr of operation. This paper provides background on the NEXT PPU and the capacitor failures. It discusses the failure investigation approach, the beam supply power switching topology and its operating modes, capacitor characteristics and circuit testing. Finally, it identifies root cause of the failures to be the unusual confluence of circuit switching frequency, the physical layout of the power circuits, and the characteristics of the capacitor.

Lack of exercise is a major cause of chronic diseases

PubMed Central

Booth, Frank W.; Roberts, Christian K.; Laye, Matthew J.

2014-01-01

Chronic diseases are major killers in the modern era. Physical inactivity is a primary cause of most chronic diseases. The initial third of the article considers: activity and prevention definitions; historical evidence showing physical inactivity is detrimental to health and normal organ functional capacities; cause vs. treatment; physical activity and inactivity mechanisms differ; gene-environment interaction [including aerobic training adaptations, personalized medicine, and co-twin physical activity]; and specificity of adaptations to type of training. Next, physical activity/exercise is examined as primary prevention against 35 chronic conditions [Accelerated biological aging/premature death, low cardiorespiratory fitness (VO2max), sarcopenia, metabolic syndrome, obesity, insulin resistance, prediabetes, type 2 diabetes, non-alcoholic fatty liver disease, coronary heart disease, peripheral artery disease, hypertension, stroke, congestive heart failure, endothelial dysfunction, arterial dyslipidemia, hemostasis, deep vein thrombosis, cognitive dysfunction, depression and anxiety, osteoporosis, osteoarthritis, balance, bone fracture/falls, rheumatoid arthritis, colon cancer, breast cancer, endometrial cancer, gestational diabetes, preeclampsia, polycystic ovary syndrome, erectile dysfunction, pain, diverticulitis, constipation, and gallbladder diseases]. The article ends with consideration of deterioration of risk factors in longer-term sedentary groups; clinical consequences of inactive childhood/adolescence; and public policy. In summary, the body rapidly maladapts to insufficient physical activity, and if continued, results in substantial decreases in both total and quality years of life. Taken together, conclusive evidence exists that physical inactivity is one important cause of most chronic diseases. In addition, physical activity primarily prevents, or delays, chronic diseases, implying that chronic disease need not be an inevitable outcome during life. PMID:23798298

Lack of exercise is a major cause of chronic diseases.

PubMed

Booth, Frank W; Roberts, Christian K; Laye, Matthew J

2012-04-01

Chronic diseases are major killers in the modern era. Physical inactivity is a primary cause of most chronic diseases. The initial third of the article considers: activity and prevention definitions; historical evidence showing physical inactivity is detrimental to health and normal organ functional capacities; cause versus treatment; physical activity and inactivity mechanisms differ; gene-environment interaction (including aerobic training adaptations, personalized medicine, and co-twin physical activity); and specificity of adaptations to type of training. Next, physical activity/exercise is examined as primary prevention against 35 chronic conditions [accelerated biological aging/premature death, low cardiorespiratory fitness (VO2max), sarcopenia, metabolic syndrome, obesity, insulin resistance, prediabetes, type 2 diabetes, nonalcoholic fatty liver disease, coronary heart disease, peripheral artery disease, hypertension, stroke, congestive heart failure, endothelial dysfunction, arterial dyslipidemia, hemostasis, deep vein thrombosis, cognitive dysfunction, depression and anxiety, osteoporosis, osteoarthritis, balance, bone fracture/falls, rheumatoid arthritis, colon cancer, breast cancer, endometrial cancer, gestational diabetes, pre-eclampsia, polycystic ovary syndrome, erectile dysfunction, pain, diverticulitis, constipation, and gallbladder diseases]. The article ends with consideration of deterioration of risk factors in longer-term sedentary groups; clinical consequences of inactive childhood/adolescence; and public policy. In summary, the body rapidly maladapts to insufficient physical activity, and if continued, results in substantial decreases in both total and quality years of life. Taken together, conclusive evidence exists that physical inactivity is one important cause of most chronic diseases. In addition, physical activity primarily prevents, or delays, chronic diseases, implying that chronic disease need not be an inevitable outcome during life. © 2012 American Physiological Society. Compr Physiol 2:1143-1211, 2012.

Dose-response association of moderate-to-vigorous physical activity with cardiovascular biomarkers and all-cause mortality: Considerations by individual sports, exercise and recreational physical activities.

PubMed

Loprinzi, Paul D

2015-12-01

Previous research demonstrates that moderate-to-vigorous physical activity (MVPA) is associated with reduced all-cause mortality risk. Our understanding of whether individual physical activities are associated with all-cause mortality is less understood. Data from the 1999-2006 NHANES were employed, with follow-up through 2011. 48 different individual physical activities (e.g., swimming, running, bicycling) were assessed, and total MVPA MET-min-month was calculated based on their responses to these 48 individual physical activities. Greater engagement in MVPA was associated with more favorable cardiovascular biomarkers, particularly for men. Even after adjustment for total MVPA, different individual physical activities were associated with cardiovascular biomarkers across gender. When compared to those not meeting guidelines (0-1999 MVPA MET-min-month), a dose-response association between MVPA and mortality was observed, with those engaging in 5 times the guideline level having the lowest risk of all-cause mortality (45% reduced risk). There was no evidence of a harmful effect of very high MVPA (e.g., 20,000+ MVPA MET-min-month). Engaging in MVPA even below the minimum recommendation was associated with survival benefits, and the greatest survival effects occurred at a dose of approximately 5 times the minimum recommendation. Although very high levels (e.g., 10 times the minimum recommendation) of self-reported MVPA did not demonstrate the greatest survival effects, high levels of physical activity did not appear to have harmful effects. Copyright © 2015 Elsevier Inc. All rights reserved.

DNA double-strand–break complexity levels and their possible contributions to the probability for error-prone processing and repair pathway choice

PubMed Central

Schipler, Agnes; Iliakis, George

2013-01-01

Although the DNA double-strand break (DSB) is defined as a rupture in the double-stranded DNA molecule that can occur without chemical modification in any of the constituent building blocks, it is recognized that this form is restricted to enzyme-induced DSBs. DSBs generated by physical or chemical agents can include at the break site a spectrum of base alterations (lesions). The nature and number of such chemical alterations define the complexity of the DSB and are considered putative determinants for repair pathway choice and the probability that errors will occur during this processing. As the pathways engaged in DSB processing show distinct and frequently inherent propensities for errors, pathway choice also defines the error-levels cells opt to accept. Here, we present a classification of DSBs on the basis of increasing complexity and discuss how complexity may affect processing, as well as how it may cause lethal or carcinogenic processing errors. By critically analyzing the characteristics of DSB repair pathways, we suggest that all repair pathways can in principle remove lesions clustering at the DSB but are likely to fail when they encounter clusters of DSBs that cause a local form of chromothripsis. In the same framework, we also analyze the rational of DSB repair pathway choice. PMID:23804754

Hot cracking of Structural Steel during Laser Welding

NASA Astrophysics Data System (ADS)

Pineda Huitron, Rosa M.; Vuorinen, Esa

2017-10-01

Laser welding is an important technique in many industries due to its high precision in operation, its local and fast processing, narrow welds and its good weld surface quality. However, the process can involve some complications due to the rapid heating and cooling of the material processed, resulting in physical and metallurgical effects as thermal contraction during solidification, giving as a result the presence of residual stresses in the narrow weld. Formation of defects during the process is an important topic to be evaluated in order to achieve better performance of the steels in use. In the present work, defects formed during laser welding of a structural steel have been investigated. The defects formed have been identified and the causes of the defects are discussed. Possible strategies for improvement of the welding procedure and final weld result are proposed. The defects were analysed by optical and scanning electron microscopy and hardness measurement. Cracks were located in the middle of the fusion zone and followed both inter-granular and trans-granular paths. Impurities as manganese sulphides were found along the welding direction, and could act as sites for crack formation. The cracks formed during solidification of the weld are identified as solidification cracks. This kind of cracks is usually caused by solidification shrinkage and thermal contractions during the process, which appear in the fusion zone and sometimes in the heat affected zone.

High Assurance Control of Cyber-Physical Systems with Application to Unmanned Aircraft Systems

NASA Astrophysics Data System (ADS)

Kwon, Cheolhyeon

With recent progress in the networked embedded control technology, cyber attacks have become one of the major threats to Cyber-Physical Systems (CPSs) due to their close integration of physical processes, computational resources, and communication capabilities. While CPSs have various applications in both military and civilian uses, their on-board automation and communication afford significant advantages over a system without such abilities, but these benefits come at the cost of possible vulnerability to cyber attacks. Traditionally, most cyber security studies in CPSs are mainly based on the computer security perspective, focusing on issues such as the trustworthiness of data flow, without rigorously considering the system's physical processes such as real-time dynamic behaviors. While computer security components are key elements in the hardware/software layer, these methods alone are not sufficient for diagnosing the healthiness of the CPSs' physical behavior. In seeking to address this problem, this research work proposes a control theoretic perspective approach which can accurately represent the interactions between the physical behavior and the logical behavior (computing resources) of the CPS. Then a controls domain aspect is explored extending beyond just the logical process of the CPS to include the underlying physical behavior. This approach will allow the CPS whose physical operations are robust/resilient to the damage caused by cyber attacks, successfully complementing the existing CPS security architecture. It is important to note that traditional fault-tolerant/robust control methods could not be directly applicable to achieve resiliency against malicious cyber attacks which can be designed sophisticatedly to spoof the security/safety monitoring system (note this is different from common faults). Thus, security issues at this layer require different risk management to detect cyber attacks and mitigate their impact within the context of a unified physical and logical process model of the CPS. Specifically, three main tasks are discussed in this presentation: (i) we first investigate diverse granularity of the interactions inside the CPS and propose feasible cyber attack models to characterize the compromised behavior of the CPS with various measures, from its severity to detectability; (ii) based on this risk information, our approach to securing the CPS addresses both monitoring of and high assurance control design against cyber attacks by developing on-line safety assessment and mitigation algorithms; and (iii) by extending the developed theories and methods from a single CPS to multiple CPSs, we examine the security and safety of multi-CPS network that are strongly dependent on the network topology, cooperation protocols between individual CPSs, etc. The effectiveness of the analytical findings is demonstrated and validated with illustrative examples, especially unmanned aircraft system (UAS) applications.

Relationship between neural rhythm generation disorders and physical disabilities in Parkinson's disease patients' walking.

PubMed

Ota, Leo; Uchitomi, Hirotaka; Ogawa, Ken-ichiro; Orimo, Satoshi; Miyake, Yoshihiro

2014-01-01

Walking is generated by the interaction between neural rhythmic and physical activities. In fact, Parkinson's disease (PD), which is an example of disease, causes not only neural rhythm generation disorders but also physical disabilities. However, the relationship between neural rhythm generation disorders and physical disabilities has not been determined. The aim of this study was to identify the mechanism of gait rhythm generation. In former research, neural rhythm generation disorders in PD patients' walking were characterized by stride intervals, which are more variable and fluctuate randomly. The variability and fluctuation property were quantified using the coefficient of variation (CV) and scaling exponent α. Conversely, because walking is a dynamic process, postural reflex disorder (PRD) is considered the best way to estimate physical disabilities in walking. Therefore, we classified the severity of PRD using CV and α. Specifically, PD patients and healthy elderly were classified into three groups: no-PRD, mild-PRD, and obvious-PRD. We compared the contributions of CV and α to the accuracy of this classification. In this study, 45 PD patients and 17 healthy elderly people walked 200 m. The severity of PRD was determined using the modified Hoehn-Yahr scale (mH-Y). People with mH-Y scores of 2.5 and 3 had mild-PRD and obvious-PRD, respectively. As a result, CV differentiated no-PRD from PRD, indicating the correlation between CV and PRD. Considering that PRD is independent of neural rhythm generation, this result suggests the existence of feedback process from physical activities to neural rhythmic activities. Moreover, α differentiated obvious-PRD from mild-PRD. Considering α reflects the intensity of interaction between factors, this result suggests the change of the interaction. Therefore, the interaction between neural rhythmic and physical activities is thought to plays an important role for gait rhythm generation. These characteristics have potential to evaluate the symptoms of PD.

[Research Progress on the Interaction Effects and Its Neural Mechanisms between Physical Fatigue and Mental Fatigue].

PubMed

Zhang, Lixin; Zhang, Chuncui; He, Feng; Zhao, Xin; Qi, Hongzhi; Wan, Baikun; Ming, Dong

2015-10-01

Fatigue is an exhaustion state caused by prolonged physical work and mental work, which can reduce working efficiency and even cause industrial accidents. Fatigue is a complex concept involving both physiological and psychological factors. Fatigue can cause a decline of concentration and work performance and induce chronic diseases. Prolonged fatigue may endanger life safety. In most of the scenarios, physical and mental workloads co-lead operator into fatigue state. Thus, it is very important to study the interaction influence and its neural mechanisms between physical and mental fatigues. This paper introduces recent progresses on the interaction effects and discusses some research challenges and future development directions. It is believed that mutual influence between physical fatigue and mental fatigue may occur in the central nervous system. Revealing the basal ganglia function and dopamine release may be important to explore the neural mechanisms between physical fatigue and mental fatigue. Future effort is to optimize fatigue models, to evaluate parameters and to explore the neural mechanisms so as to provide scientific basis and theoretical guidance for complex task designs and fatigue monitoring.

A systematic review of the evidence for Canada's Physical Activity Guidelines for Adults

PubMed Central

2010-01-01

This systematic review examines critically the scientific basis for Canada's Physical Activity Guide for Healthy Active Living for adults. Particular reference is given to the dose-response relationship between physical activity and premature all-cause mortality and seven chronic diseases (cardiovascular disease, stroke, hypertension, colon cancer, breast cancer, type 2 diabetes (diabetes mellitus) and osteoporosis). The strength of the relationship between physical activity and specific health outcomes is evaluated critically. Literature was obtained through searching electronic databases (e.g., MEDLINE, EMBASE), cross-referencing, and through the authors' knowledge of the area. For inclusion in our systematic review articles must have at least 3 levels of physical activity and the concomitant risk for each chronic disease. The quality of included studies was appraised using a modified Downs and Black tool. Through this search we identified a total of 254 articles that met the eligibility criteria related to premature all-cause mortality (N = 70), cardiovascular disease (N = 49), stroke (N = 25), hypertension (N = 12), colon cancer (N = 33), breast cancer (N = 43), type 2 diabetes (N = 20), and osteoporosis (N = 2). Overall, the current literature supports clearly the dose-response relationship between physical activity and the seven chronic conditions identified. Moreover, higher levels of physical activity reduce the risk for premature all-cause mortality. The current Canadian guidelines appear to be appropriate to reduce the risk for the seven chronic conditions identified above and all-cause mortality. PMID:20459783

Prevalence and Treatment Patterns of Physical Impairments in Patients With Metastatic Breast Cancer

PubMed Central

Cheville, Andrea L.; Troxel, Andrea B.; Basford, Jeffrey R.; Kornblith, Alice B.

2014-01-01

Purpose Physical impairments cause profound functional declines in patients with cancer. Although common rehabilitation measures can address many impairments, the extent of their delivery is unknown. We studied these issues by quantifying physical impairments in patients with metastatic breast cancer and by assessing how they are addressed. Patients and Methods A consecutive sample of 163 community-dwelling patients with metastatic breast cancer was stratified by Karnofsky performance score and administered the Medical Outcomes Study Physical Function Subscale and the Older Americans Resource Study Activities of Daily Living subscales. Cancer-related physical impairments were identified through a physical examination, the 6-Minute Walk Test, and the Functional Independence Measure Mobility Subscale. Patients were questioned regarding the nature, type, and setting of treatments for impairments. Physical rehabilitation needs were determined through a consensus process involving physiatrists and physical/occupational therapists specializing in cancer. Results Ninety-two percent of patients (150 of 163) had at least one physical impairment. Among 530 identified impairments, 484 (92%) required a physical rehabilitation intervention and 469 (88%) required physical therapy (PT) and/or occupational therapy (OT). Only 30% of impairments requiring rehabilitation services and 21% of those requiring PT/OT received treatment. Impairments detected during hospitalization were overwhelmingly more likely to receive a rehabilitation intervention (odds ratio [OR] = 87.9; 95% CI, 28.5 to 271.4), and PT/OT (OR = 558.8; 95% CI, 187.0 to 1,669.6). Low socioeconomic and minority status were significantly associated with nontreatment. Conclusion Remediable physical impairments were prevalent and poorly addressed among patients with metastatic breast cancer, drastically so in the outpatient setting. Undertreatment was particularly prominent among minority and socioeconomically disadvantaged groups. PMID:18509174

Physical activity is independently associated with reduced mortality: 15-years follow-up of the Hordaland Health Study (HUSK)

PubMed Central

Kopperstad, Øyvind; Skogen, Jens Christoffer; Sivertsen, Børge; Tell, Grethe S.

2017-01-01

Background Physical activity (PA) is associated with lower risk for non-communicable diseases and mortality. We aimed to investigate the prospective association between PA and all-cause and cause-specific mortality, and the impact of other potentially contributing factors. Method Data from the community-based Hordaland Health Study (HUSK, 1997–99) were linked to the Norwegian Cause of Death Registry. The study included 20,506 individuals born 1950–1957 and 2,225 born in 1925–1927 (baseline age 40–49 and 70–74). Based on self-report, individuals were grouped as habitually performing low intensity, short duration, low intensity, longer duration or high intensity PA. The hazard ratios (HR) for all-cause and cause-specific mortality during follow-up were calculated. Measures of socioeconomic status, physical health, mental health, smoking and alcohol consumption were added separately and cumulatively to the model. Results PA was associated with lower all-cause mortality in both older (HR 0.75 (95% CI 0.67–0.84)) and younger individuals (HR 0.82 (95% CI 0.72–0.92)) (crude models, HR: risk associated with moving from low intensity, short duration to low intensity, longer duration PA, and from low intensity, longer duration to high intensity). Smoking, education, somatic diagnoses and mental health accounted for some of the association between physical activity and mortality, but a separate protective effect of PA remained in fully adjusted models for cardiovascular (HR 0.78 (95% CI 0.66–0.92)) and respiratory (HR 0.45 (95% CI 0.32–0.63) mortality (both age-groups together), as well as all-cause mortality in the older age group (HR 0.74, 95%CI 0.66–0.83). Conclusion Low intensity, longer duration and high intensity physical activity was associated with reduced all-cause, respiratory and cardiovascular mortality, indicating that physical activity is beneficial also among older individuals, and that a moderate increase in PA can be beneficial. PMID:28328994

Physical and mental health functioning after all-cause and diagnosis-specific sickness absence: a register-linkage follow-up study among ageing employees.

PubMed

Mänty, Minna; Lallukka, Tea; Lahti, Jouni; Pietiläinen, Olli; Laaksonen, Mikko; Lahelma, Eero; Rahkonen, Ossi

2017-01-25

Sickness absence has been shown to be a risk marker for severe future health outcomes, such as disability retirement and premature death. However, it is poorly understood how all-cause and diagnosis-specific sickness absence is reflected in subsequent physical and mental health functioning over time. The aim of this study was to examine the association of all-cause and diagnosis-specific sickness absence with subsequent changes in physical and mental health functioning among ageing municipal employees. Prospective survey and register data from the Finnish Helsinki Health Study and the Social Insurance Institution of Finland were used. Register based records for medically certified all-cause and diagnostic-specific sickness absence spells (>14 consecutive calendar days) in 2004-2007 were examined in relation to subsequent physical and mental health functioning measured by Short-Form 36 questionnaire in 2007 and 2012. In total, 3079 respondents who were continuously employed over the sickness absence follow-up were included in the analyses. Repeated-measures analysis was used to examine the associations. During the 3-year follow-up, 30% of the participants had at least one spell of medically certified sickness absence. All-cause sickness absence was associated with lower subsequent physical and mental health functioning in a stepwise manner: the more absence days, the poorer the subsequent physical and mental health functioning. These differences remained but narrowed slightly during the follow-up. Furthermore, the adverse association for physical health functioning was strongest among those with sickness absence due to diseases of musculoskeletal or respiratory systems, and on mental functioning among those with sickness absence due to mental disorders. Sickness absence showed a persistent adverse stepwise association with subsequent physical and mental health functioning. Evidence on health-related outcomes after long-term sickness absence may provide useful information for targeted interventions to promote health and workability.

Physics Manpower, 1973, Education and Employment Studies.

ERIC Educational Resources Information Center

American Inst. of Physics, New York, NY.

Discussed in this document are the changes within the physics profession, their causes and effect. Detailed statistical data are supplied concerning physics enrollments, the institutions where physics is taught, the faculty in physics departments, and the nonacademic employment of physicists. Other topics include employment, education, minority…

Diffusion-advection within dynamic biological gaps driven by structural motion

NASA Astrophysics Data System (ADS)

Asaro, Robert J.; Zhu, Qiang; Lin, Kuanpo

2018-04-01

To study the significance of advection in the transport of solutes, or particles, within thin biological gaps (channels), we examine theoretically the process driven by stochastic fluid flow caused by random thermal structural motion, and we compare it with transport via diffusion. The model geometry chosen resembles the synaptic cleft; this choice is motivated by the cleft's readily modeled structure, which allows for well-defined mechanical and physical features that control the advection process. Our analysis defines a Péclet-like number, AD, that quantifies the ratio of time scales of advection versus diffusion. Another parameter, AM, is also defined by the analysis that quantifies the full potential extent of advection in the absence of diffusion. These parameters provide a clear and compact description of the interplay among the well-defined structural, geometric, and physical properties vis-a ̀-vis the advection versus diffusion process. For example, it is found that AD˜1 /R2 , where R is the cleft diameter and hence diffusion distance. This curious, and perhaps unexpected, result follows from the dependence of structural motion that drives fluid flow on R . AM, on the other hand, is directly related (essentially proportional to) the energetic input into structural motion, and thereby to fluid flow, as well as to the mechanical stiffness of the cleftlike structure. Our model analysis thus provides unambiguous insight into the prospect of competition of advection versus diffusion within biological gaplike structures. The importance of the random, versus a regular, nature of structural motion and of the resulting transient nature of advection under random motion is made clear in our analysis. Further, by quantifying the effects of geometric and physical properties on the competition between advection and diffusion, our results clearly demonstrate the important role that metabolic energy (ATP) plays in this competitive process.

[Dynamics of soil physical properties and biological soil crust during the vegetation restoration process of abandoned croplands in the Ordos Plateau, China].

PubMed

Cai, Wen Tao; Li, He Yi; Lai, Li Ming; Zhang, Xiao Long; Guan, Tian Yu; Zhou, Ji Hua; Jiang, Lian He; Zheng, Yuan Run

2017-03-18

A series of typical abandoned croplands in the regions of Ruanliang and Yingliang in the Ordos Plateau, China, were selected, and dynamics of the surface litter, biological soil crust and soil bulk density, soil texture, and soil moisture in different soil layers were investigated. The results showed that in the abandoned cropland in Ruanliang, the clay particle content and surface litter of the surface soil layer (0-10 cm) increased during the restoration process, while that of soil bulk density substantially decreased and soil water content slightly increased in the surface soil. In the medium soil layer (10-30 cm), the clay particle content increased and the soil water content slightly decreased. In the deep soil layer (30-50 cm), there was a relatively large variation in the physical properties. In the abandoned cropland in Yingliang, the coverage of litter and the coverage and thickness of the biological soil crust increased during the abandonment process. The surface soil bulk density, soil clay particle content and soil water content remained constant in 0-10 cm soil layer, while the physical properties varied substantially in 10-40 cm soil layer. The shallow distribution of the soil water content caused by the accumulation of the litter and clay particles on the soil surface might be the key reason of the replacement of the semi-shrub Artemisia ordosica community with a perennial grass community over the last 20 years of the abandoned cropland in Ruanliang. The relatively high soil water content in the shallow layer and the development of the biological soil crust might explain why the abandoned cropland in Yingliang was not invaded by the semi-shrub A. ordosica during the restoration process.

Development Scaffolding for Construction of Evaluation Instrument Training Program on The Cognitive Domain For Senior High School Physics Teachers and The Same Level

NASA Astrophysics Data System (ADS)

Arif, W.; Suhandi, A.; Kaniawati, I.; Setiawan, A.

2017-02-01

The development of scaffolding for evaluation instrument construction training program on the cognitive domain for senior high school physics teacher and the same level that is specified in the test instrument has been done. This development was motivated by the low ability of the majority of physics teachers in constructing the physics learning achievement test. This situation not in accordance with the demands of Permendiknas RI no. 16 tahun 2007 concerning the standard of academic qualifications and competence of teachers, stating that teachers should have a good ability to develop instruments for assessment and evaluation of process and learning outcomes. Based on the preliminary study results, it can be seen that the main cause of the inability of teachers in developing physics achievement test is because they do not good understand of the indicators for each aspect of cognitive domains. Scaffolding development is done by using the research and development methods formulated by Thiagarajan which includes define, design and develope steps. Develop step includes build the scaffolding, validation of scaffolding by experts and the limited pilot implementations on the training activities. From the build scaffolding step, resulted the scaffolding for the construction of test instruments training program which include the process steps; description of indicators, operationalization of indicators, construction the itemsframework (items scenarios), construction the items stem, construction the items and checking the items. The results of the validation by three validator indicates that the built scaffolding are suitable for use in the construction of physics achievement test training program, especially for novice. The limited pilot implementation of the built scaffolding conducted in training activities attended by 10 senior high school physics teachers in Garut district. The results of the limited pilot implementation shows that the built scaffolding have a medium effectiveness in improving the ability of senior high school physics teachers in constructing the physic achievement test instrument that is characterized by more than 70% of trainees achieve scores of test instruments construction of about 80 or more.

Influence of megapolis on the physical field variations

NASA Astrophysics Data System (ADS)

Riabova, Svetlana; Loktev, Dmitry; Spivak, Alexander

2016-04-01

The research of geophysical fields in the conditions of megapolis attracts particular interest not only in terms of their influence on the operation of precision equipment and technological processes associated with nanotechnology, but also it is perhaps the most important in terms of the formation of a special human and other biological objects' habitat. Indeed, the megapolis causes significant changes in regime of the physical fields both directly and indirectly. Negative factors of megapolis associated with elevated vibrations of soil as a result of traffic, acoustic load in the construction of infrastructure and transport communications, etc. are complemented by another negative factor, which until quite recently wasn't known much. It is a variation of physical fields (primarily electric and magnetic) induced by anthropogenic activities. As a result of the evolution a man has adapted to the natural regime of physical fields. Therefore, any, even the short-term changes of physical fields in the environment, their deviations from the natural rate can have a significant influence on human health including changes in the psycho-emotional state. In the present work we have evaluated the influence of the megapolis (in our case, Moscow) on the nature and regime of microseismic, electric and acoustic field in the surface atmosphere. We have analyzed data obtained as a result of continuous simultaneous registration of physical fields and meteorological parameters at the Center for geophysical monitoring of Moscow of Institute of Geosphere Dynamics of Russian Academy of Sciences. For determination of the characteristics of physical fields in the megapolis obtained data were compared with the results of the registration carried out at the Geophysical Observatory "Mikhnevo" of IDG RAS (located 85 km south from Moscow). The work is shown that the influence of the megapolis appears to increase the amplitude of physical fields, change of their spectral composition, disturbance of natural periodicities. The important factor characterized the megapolis is the presence of man-made component, which has a significant influence on the course of natural physical processes in the near-surface atmosphere.

Computational fluid dynamics and frequency-dependent finite-difference time-domain method coupling for the interaction between microwaves and plasma in rocket plumes

NASA Astrophysics Data System (ADS)

Kinefuchi, K.; Funaki, I.; Shimada, T.; Abe, T.

2012-10-01

Under certain conditions during rocket flights, ionized exhaust plumes from solid rocket motors may interfere with radio frequency transmissions. To understand the relevant physical processes involved in this phenomenon and establish a prediction process for in-flight attenuation levels, we attempted to measure microwave attenuation caused by rocket exhaust plumes in a sea-level static firing test for a full-scale solid propellant rocket motor. The microwave attenuation level was calculated by a coupling simulation of the inviscid-frozen-flow computational fluid dynamics of an exhaust plume and detailed analysis of microwave transmissions by applying a frequency-dependent finite-difference time-domain method with the Drude dispersion model. The calculated microwave attenuation level agreed well with the experimental results, except in the case of interference downstream the Mach disk in the exhaust plume. It was concluded that the coupling estimation method based on the physics of the frozen plasma flow with Drude dispersion would be suitable for actual flight conditions, although the mixing and afterburning in the plume should be considered depending on the flow condition.

The best of the best discourse on health: poetic insights on how professional sport socializes a family of men into hegemonic masculinity and physical inactivity.

PubMed

Madill, Leanna; Hopper, Timothy F

2007-03-01

This study examines how 4 men from the same family, representing different generations, construct health from their perceptions of professional athletes. Many men are socialized and participate in sport discourses that promote certain truths about being a man that often have detrimental effects to their health. The capacity of research to inform men's construction of health is limited. In an attempt to engage male participants within the research process and cause a form of catalytic validity, transcripts from interviews with the men were analyzed, and thematic findings were represented in a poetic form and shared with the participants for discussion and refinement. The findings revealed how the male participants reiterated messages that the media promotes, such as the importance of physical and mental strength for a man. More significantly, the men became aware that they assumed a narrow definition of health portrayed by professional athletics that perpetuated a hegemonic masculinity. Reflections on changes in the men's lifestyle choices after engaging in the research process are offered in the conclusion.

The interplay between human population dynamics and flooding in Bangladesh: a spatial analysis

NASA Astrophysics Data System (ADS)

di Baldassarre, G.; Yan, K.; Ferdous, MD. R.; Brandimarte, L.

2014-09-01

In Bangladesh, socio-economic and hydrological processes are both extremely dynamic and inter-related. Human population patterns are often explained as a response, or adaptation strategy, to physical events, e.g. flooding, salt-water intrusion, and erosion. Meanwhile, these physical processes are exacerbated, or mitigated, by diverse human interventions, e.g. river diversion, levees and polders. In this context, this paper describes an attempt to explore the complex interplay between floods and societies in Bangladeshi floodplains. In particular, we performed a spatially-distributed analysis of the interactions between the dynamics of human settlements and flood inundation patterns. To this end, we used flooding simulation results from inundation modelling, LISFLOOD-FP, as well as global datasets of population distribution data, such as the Gridded Population of the World (20 years, from 1990 to 2010) and HYDE datasets (310 years, from 1700 to 2010). The outcomes of this work highlight the behaviour of Bangladeshi floodplains as complex human-water systems and indicate the need to go beyond the traditional narratives based on one-way cause-effects, e.g. climate change leading to migrations.

Are Older Adults Less Embodied? A Review of Age Effects through the Lens of Embodied Cognition

PubMed Central

Costello, Matthew C.; Bloesch, Emily K.

2017-01-01

Embodied cognition is a theoretical framework which posits that cognitive function is intimately intertwined with the body and physical actions. Although the field of psychology is increasingly accepting embodied cognition as a viable theory, it has rarely been employed in the gerontological literature. However, embodied cognition would appear to have explanatory power for aging research given that older adults typically manifest concurrent physical and mental changes, and that research has indicated a correlative relationship between such changes. The current paper reviews age-related changes in sensory processing, mental representation, and the action-perception relationship, exploring how each can be understood through the lens of embodied cognition. Compared to younger adults, older adults exhibit across all three domains an increased tendency to favor visual processing over bodily factors, leading to the conclusion that older adults are less embodied than young adults. We explore the significance of this finding in light of existing theoretical models of aging and argue that embodied cognition can benefit gerontological research by identifying further factors that can explain the cause of age-related declines. PMID:28289397

IJA: an efficient algorithm for query processing in sensor networks.

PubMed

Lee, Hyun Chang; Lee, Young Jae; Lim, Ji Hyang; Kim, Dong Hwa

2011-01-01

One of main features in sensor networks is the function that processes real time state information after gathering needed data from many domains. The component technologies consisting of each node called a sensor node that are including physical sensors, processors, actuators and power have advanced significantly over the last decade. Thanks to the advanced technology, over time sensor networks have been adopted in an all-round industry sensing physical phenomenon. However, sensor nodes in sensor networks are considerably constrained because with their energy and memory resources they have a very limited ability to process any information compared to conventional computer systems. Thus query processing over the nodes should be constrained because of their limitations. Due to the problems, the join operations in sensor networks are typically processed in a distributed manner over a set of nodes and have been studied. By way of example while simple queries, such as select and aggregate queries, in sensor networks have been addressed in the literature, the processing of join queries in sensor networks remains to be investigated. Therefore, in this paper, we propose and describe an Incremental Join Algorithm (IJA) in Sensor Networks to reduce the overhead caused by moving a join pair to the final join node or to minimize the communication cost that is the main consumer of the battery when processing the distributed queries in sensor networks environments. At the same time, the simulation result shows that the proposed IJA algorithm significantly reduces the number of bytes to be moved to join nodes compared to the popular synopsis join algorithm.

IJA: An Efficient Algorithm for Query Processing in Sensor Networks

PubMed Central

Lee, Hyun Chang; Lee, Young Jae; Lim, Ji Hyang; Kim, Dong Hwa

2011-01-01

One of main features in sensor networks is the function that processes real time state information after gathering needed data from many domains. The component technologies consisting of each node called a sensor node that are including physical sensors, processors, actuators and power have advanced significantly over the last decade. Thanks to the advanced technology, over time sensor networks have been adopted in an all-round industry sensing physical phenomenon. However, sensor nodes in sensor networks are considerably constrained because with their energy and memory resources they have a very limited ability to process any information compared to conventional computer systems. Thus query processing over the nodes should be constrained because of their limitations. Due to the problems, the join operations in sensor networks are typically processed in a distributed manner over a set of nodes and have been studied. By way of example while simple queries, such as select and aggregate queries, in sensor networks have been addressed in the literature, the processing of join queries in sensor networks remains to be investigated. Therefore, in this paper, we propose and describe an Incremental Join Algorithm (IJA) in Sensor Networks to reduce the overhead caused by moving a join pair to the final join node or to minimize the communication cost that is the main consumer of the battery when processing the distributed queries in sensor networks environments. At the same time, the simulation result shows that the proposed IJA algorithm significantly reduces the number of bytes to be moved to join nodes compared to the popular synopsis join algorithm. PMID:22319375

Distance Perception of Stereoscopically Presented Virtual Objects Optically Superimposed on Physical Objects by a Head-Mounted See-Through Display

NASA Technical Reports Server (NTRS)

Ellis, Stephen R.; Bucher, Urs J.; Statler, Irving C. (Technical Monitor)

1994-01-01

The influence of physically presented background stimuli on the perceived depth of optically overlaid, stereoscopic virtual images has been studied using headmounted stereoscopic, virtual image displays. These displays allow presentation of physically unrealizable stimulus combinations. Positioning of an opaque physical object either at the initial perceived depth of the virtual image or at a position substantially in front of the virtual image, causes the virtual image to perceptually move closer to the observer. In the case of objects positioned substantially in front of the virtual image, subjects often perceive the opaque object to become transparent. Evidence is presented that the apparent change of position caused by interposition of the physical object is not due to occlusion cues. According, it may have an alternative cause such as variation in the binocular vengeance position of the eyes caused by introduction of the physical object. This effect may complicate design of overlaid virtual image displays for near objects and appears to be related to the relative conspicuousness of the overlaid virtual image and the background. Consequently, it may be related to earlier analyses of John Foley which modeled open-loop pointing errors to stereoscopically presented points of light in terms of errors in determination of a reference point for interpretation of observed retinal disparities. Implications for the design of see-through displays for manufacturing will be discussed.

Structural optimization under overhang constraints imposed by additive manufacturing technologies

NASA Astrophysics Data System (ADS)

Allaire, G.; Dapogny, C.; Estevez, R.; Faure, A.; Michailidis, G.

2017-12-01

This article addresses one of the major constraints imposed by additive manufacturing processes on shape optimization problems - that of overhangs, i.e. large regions hanging over void without sufficient support from the lower structure. After revisiting the 'classical' geometric criteria used in the literature, based on the angle between the structural boundary and the build direction, we propose a new mechanical constraint functional, which mimics the layer by layer construction process featured by additive manufacturing technologies, and thereby appeals to the physical origin of the difficulties caused by overhangs. This constraint, as well as some variants, is precisely defined; their shape derivatives are computed in the sense of Hadamard's method, and numerical strategies are extensively discussed, in two and three space dimensions, to efficiently deal with the appearance of overhang features in the course of shape optimization processes.

Hydraulic Physical Model of Debris Flow for Malaysia Case Study

NASA Astrophysics Data System (ADS)

Arif Zainol, M. R. R. Mohd; Awahab, M. K.

2018-06-01

In the recent decade, several debris flow events occurred and caused hundreds of deaths, missing or injury and damaged many facilities. In addition to causing significant morphological changes along riverbeds and mountain slopes, these flows are frequently reported to bring about extensive property damage and loss of life. Debris flow phenomena occasionally occur in Malaysia and numbers of death reported cause by this event. In order to investigate the debris flow and its deposition process, experiments were conducted at the School of Civil Engineering Laboratory, Universiti Sains Malaysia. The models consists of three main parts which are water tank, rectangular flume and deposition board. A high speed video camera (HSVC) had been placed nearly downstream of the rectangular flume to capture the movement characteristics of particle grain. From this study, the characteristics of particle routing segregation can be understand clearly, therefore this input will be a very useful information to other researchers for further investigation in terms of knowledge sharing between researchers. Catastrophic cause by debris flow event can be minimized therefore in term of economy losses can be reduce and human life can be safe.

Leukopenia in familial Mediterranean fever: case series and literature review with special emphasis on pathogenesis.

PubMed

Aslan, Deniz

2014-03-01

Leukopenia is a blood disease in which the number of circulating white blood cells diminishes. All underlying causes of leukopenia are not yet known. The subjects of this study are 15 leukopenic patients who were assessed by a systemic workup, including physical examination, blood tests, and molecular analysis. A common and unusual cause was revealed in all patients. This cause was a disorder with a laboratory characteristic of leukocytosis, namely familial Mediterranean fever (FMF). It was discussed that leukopenia arising in the context of FMF is mainly due to autophagy and apoptosis processes. These two pathophysiological characteristics of FMF were thought to explain the particular (episodic and self-limited) leukopenia in this disorder. Based on the results of this study in conjunction with the currently existing literature data, we suggest that FMF causes leukopenia. Leukopenic cases should be investigated for FMF, particularly if the leukopenia is episodic in nature. Early recognition of FMF would help to skip unnecessary invasive procedures and to prevent the development of amyloidosis, the devastating complication of FMF.

A Community Based Systems Diagram of Obesity Causes.

PubMed

Allender, Steven; Owen, Brynle; Kuhlberg, Jill; Lowe, Janette; Nagorcka-Smith, Phoebe; Whelan, Jill; Bell, Colin

2015-01-01

Application of system thinking to the development, implementation and evaluation of childhood obesity prevention efforts represents the cutting edge of community-based prevention. We report on an approach to developing a system oriented community perspective on the causes of obesity. Group model building sessions were conducted in a rural Australian community to address increasing childhood obesity. Stakeholders (n = 12) built a community model that progressed from connection circles to causal loop diagrams using scripts from the system dynamics literature. Participants began this work in identifying change over time in causes and effects of childhood obesity within their community. The initial causal loop diagram was then reviewed and elaborated by 50 community leaders over a full day session. The process created a causal loop diagram representing community perceptions of determinants and causes of obesity. The causal loop diagram can be broken down into four separate domains; social influences; fast food and junk food; participation in sport; and general physical activity. This causal loop diagram can provide the basis for community led planning of a prevention response that engages with multiple levels of existing settings and systems.

Fatigue failure of osteocyte cellular processes: implications for the repair of bone.

PubMed

Dooley, C; Cafferky, D; Lee, T C; Taylor, D

2014-01-25

The physical effects of fatigue failure caused by cyclic strain are important and for most materials well understood. However, nothing is known about this mode of failure in living cells. We developed a novel method that allowed us to apply controlled levels of cyclic displacement to networks of osteocytes in bone. We showed that under cyclic loading, fatigue failure takes place in the dendritic processes of osteocytes at cyclic strain levels as low as one tenth of the strain needed for instantaneous rupture. The number of cycles to failure was inversely correlated with the strain level. Further experiments demonstrated that these failures were not artefacts of our methods of sample preparation and testing, and that fatigue failure of cell processes also occurs in vivo. This work is significant as it is the first time it has been possible to conduct fatigue testing on cellular material of any kind. Many types of cells experience repetitive loading which may cause failure or damage requiring repair. It is clinically important to determine how cyclic strain affects cells and how they respond in order to gain a deeper understanding of the physiological processes stimulated in this manner. The more we understand about the natural repair process in bone the more targeted the intervention methods may become if disruption of the repair process occurred. Our results will help to understand how the osteocyte cell network is disrupted in the vicinity of matrix damage, a crucial step in bone remodelling.

A data transmission method for particle physics experiments based on Ethernet physical layer

NASA Astrophysics Data System (ADS)

Huang, Xi-Ru; Cao, Ping; Zheng, Jia-Jun

2015-11-01

Due to its advantages of universality, flexibility and high performance, fast Ethernet is widely used in readout system design for modern particle physics experiments. However, Ethernet is usually used together with the TCP/IP protocol stack, which makes it difficult to implement readout systems because designers have to use the operating system to process this protocol. Furthermore, TCP/IP degrades the transmission efficiency and real-time performance. To maximize the performance of Ethernet in physics experiment applications, a data readout method based on the physical layer (PHY) is proposed. In this method, TCP/IP is replaced with a customized and simple protocol, which makes it easier to implement. On each readout module, data from the front-end electronics is first fed into an FPGA for protocol processing and then sent out to a PHY chip controlled by this FPGA for transmission. This kind of data path is fully implemented by hardware. From the side of the data acquisition system (DAQ), however, the absence of a standard protocol causes problems for the network related applications. To solve this problem, in the operating system kernel space, data received by the network interface card is redirected from the traditional flow to a specified memory space by a customized program. This memory space can easily be accessed by applications in user space. For the purpose of verification, a prototype system has been designed and implemented. Preliminary test results show that this method can meet the requirements of data transmission from the readout module to the DAQ with an efficient and simple manner. Supported by National Natural Science Foundation of China (11005107) and Independent Projects of State Key Laboratory of Particle Detection and Electronics (201301)

Self-Reported Physical Quality of Life Before Thoracic Operations Is Associated With Long-Term Survival.

PubMed

Al-Ameri, Mamdoh; Bergman, Per; Franco-Cereceda, Anders; Sartipy, Ulrik

2017-02-01

The aim was to analyze the association between baseline self-reported health-related quality of life and long-term survival after thoracic operations. In a prospective population-based cohort study, we included patients scheduled for thoracic operations and obtained information about preoperative health-related quality of life using the validated quality-of-life instrument Short Form-36. Patients were categorized according to higher or lower physical and mental component scores, compared with an age- and sex-matched reference population. The primary outcome measure was all-cause mortality and was ascertained from Swedish national registers. We used Cox regression for estimation of hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between preoperative physical/mental quality of life and long-term survival while adjusting for differences in baseline characteristics, cancer stage, histopathologic process, and other factors. We included 249 patients between 2006 and 2008. During a median follow-up time of 8.0 years, 119 patients (48%) died. Having a physical component summary score less than reference was significantly associated with mortality (multivariable adjusted HR 2.02, 95% CI: 1.34 to 3.06, p = 0.001). A mental component summary score less than reference was not associated with mortality (adjusted HR 1.32, 95% CI: 0.84 to 3.06, p = 0.233). In patients who underwent thoracic operations, a self-reported physical quality of life lower than reference value was associated with significantly worse survival independent of histopathologic process, cancer stage, extent of operations, and other patient-related factors. The preoperative mental component of quality of life was not associated with long-term survival. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

The use of a running wheel to measure activity in rodents: relationship to energy balance, general activity, and reward.

PubMed

Novak, Colleen M; Burghardt, Paul R; Levine, James A

2012-03-01

Running wheels are commonly employed to measure rodent physical activity in a variety of contexts, including studies of energy balance and obesity. There is no consensus on the nature of wheel-running activity or its underlying causes, however. Here, we will begin by systematically reviewing how running wheel availability affects physical activity and other aspects of energy balance in laboratory rodents. While wheel running and physical activity in the absence of a wheel commonly correlate in a general sense, in many specific aspects the two do not correspond. In fact, the presence of running wheels alters several aspects of energy balance, including body weight and composition, food intake, and energy expenditure of activity. We contend that wheel-running activity should be considered a behavior in and of itself, reflecting several underlying behavioral processes in addition to a rodent's general, spontaneous activity. These behavioral processes include defensive behavior, predatory aggression, and depression- and anxiety-like behaviors. As it relates to energy balance, wheel running engages several brain systems-including those related to the stress response, mood, and reward, and those responsive to growth factors-that influence energy balance indirectly. We contend that wheel-running behavior represents factors in addition to rodents' tendency to be physically active, engaging additional neural and physiological mechanisms which can then independently alter energy balance and behavior. Given the impact of wheel-running behavior on numerous overlapping systems that influence behavior and physiology, this review outlines the need for careful design and interpretation of studies that utilize running wheels as a means for exercise or as a measurement of general physical activity. Copyright © 2012 Elsevier Ltd. All rights reserved.

The use of a running wheel to measure activity in rodents: Relationship to energy balance, general activity, and reward

PubMed Central

Levine, James A.

2015-01-01

Running wheels are commonly employed to measure rodent physical activity in a variety of contexts, including studies of energy balance and obesity. There is no consensus on the nature of wheel-running activity or its underlying causes, however. Here, we will begin by systematically reviewing how running wheel availability affects physical activity and other aspects of energy balance in laboratory rodents. While wheel running and physical activity in the absence of a wheel commonly correlate in a general sense, in many specific aspects the two do not correspond. In fact, the presence of running wheels alters several aspects of energy balance, including body weight and composition, food intake, and energy expenditure of activity. We contend that wheel-running activity should be considered a behavior in and of itself, reflecting several underlying behavioral processes in addition to a rodent's general, spontaneous activity. These behavioral processes include defensive behavior, predatory aggression, and depression- and anxiety-like behaviors. As it relates to energy balance, wheel running engages several brain systems—including those related to the stress response, mood, and reward, and those responsive to growth factors—that influence energy balance indirectly. We contend that wheel-running behavior represents factors in addition to rodents' tendency to be physically active, engaging additional neural and physiological mechanisms which can then independently alter energy balance and behavior. Given the impact of wheel-running behavior on numerous overlapping systems that influence behavior and physiology, this review outlines the need for careful design and interpretation of studies that utilize running wheels as a means for exercise or as a measurement of general physical activity. PMID:22230703

Measurement model as a means for studying the process of emotion origination

NASA Astrophysics Data System (ADS)

Taymanov, R.; Baksheeva, Iu; Sapozhnikova, K.; Chunovkina, A.

2016-11-01

In the last edition of the International Vocabulary of Metrology the concept “measurement” was spread outside the field of physical quantities. This fact makes it relevant to analyze the experience of developing the models of multidimensional quantity measurements. The model of measurements of expected emotions caused by musical and other acoustic impacts, is considered. The model relies upon a hypothesis of a nonlinear conversion of acoustic signals to a neurophysiological reaction giving rise to emotion. Methods for checking this hypothesis as well as experimental results are given.

Electroweak radiative corrections to the top quark decay

NASA Astrophysics Data System (ADS)

Kuruma, Toshiyuki

1993-12-01

The top quark, once produced, should be an important window to the electroweak symmetry breaking sector. We compute electroweak radiative corrections to the decay process t→b+W + in order to extract information on the Higgs sector and to fix the background in searches for a possible new physics contribution. The large Yukawa coupling of the top quark induces a new form factor through vertex corrections and causes discrepancy from the tree-level longitudinal W-boson production fraction, but the effect is of order 1% or less for m H<1 TeV.

Determination of Pressure Fluctuations in Rotor Bundle of Centrifugal Compressor at Critical Conditions of Operation

NASA Astrophysics Data System (ADS)

Levashov, V. A.; Lyubchenko, K. Yu

2017-08-01

This article describes the physical processes that occur in the stage flow part of the compressor while it is operating and can create conditions for the occurrence of forced vibrations, which in turn can lead to the destruction of the impellers. Critical conditions of compressor operation are determined. To understand that critical condition of operation is cause of the destruction of the impellers, transient CFD analysis was carried for test stage of compressor. The obtained pressure fluctuation amplitudes allow to evaluate the critical conditions of compressor operation.

Music training for the development of auditory skills.

PubMed

Kraus, Nina; Chandrasekaran, Bharath

2010-08-01

The effects of music training in relation to brain plasticity have caused excitement, evident from the popularity of books on this topic among scientists and the general public. Neuroscience research has shown that music training leads to changes throughout the auditory system that prime musicians for listening challenges beyond music processing. This effect of music training suggests that, akin to physical exercise and its impact on body fitness, music is a resource that tones the brain for auditory fitness. Therefore, the role of music in shaping individual development deserves consideration.

Investigation of Physical Processes Limiting Plasma Density in DIII--D

NASA Astrophysics Data System (ADS)

Maingi, R.

1996-11-01

Understanding the physical processes which limit operating density is crucial in achieving peak performance in confined plasmas. Studies from many of the world's tokamaks have indicated the existence(M. Greenwald, et al., Nucl. Fusion 28) (1988) 2199 of an operational density limit (Greenwald limit, n^GW_max) which is proportional to the plasma current and independent of heating power. Several theories have reproduced the current dependence, but the lack of a heating power dependence in the data has presented an enigma. This limit impacts the International Thermonuclear Experimental Reactor (ITER) because the nominal operating density for ITER is 1.5 × n^GW_max. In DIII-D, experiments are being conducted to understand the physical processes which limit operating density in H-mode discharges; these processes include X-point MARFE formation, high core recycling and neutral pressure, resistive MHD stability, and core radiative collapse. These processes affect plasma properties, i.e. edge/scrape-off layer conduction and radiation, edge pressure gradient and plasma current density profile, and core radiation, which in turn restrict the accessible density regime. With divertor pumping and D2 pellet fueling, core neutral pressure is reduced and X-point MARFE formation is effectively eliminated. Injection of the largest-sized pellets does cause transient formation of divertor MARFEs which occasionally migrate to the X-point, but these are rapidly extinguished in pumped discharges in the time between pellets. In contrast to Greenwald et al., it is found that the density relaxation time after pellets is largely independent of the density relative to the Greenwald limit. Fourier analysis of Mirnov oscillations indicates the de-stabilization and growth of rotating, tearing-type modes (m/n= 2/1) when the injected pellets cause large density perturbations, and these modes often reduce energy confinement back to L-mode levels. We are examining the mechanisms for de-stabilization of the mode, the primary ones being neo-classical pressure gradient drivers. Discharges with a gradual density increase are often free of large amplitude tearing modes, allowing access to the highest density regimes in which off-axis beam deposition can lead to core radiative collapse, i.e. a central power balance limit. The highest achieved barne was 1.5 × n^GW_max with τ_E/τ_E^JET-DIII-D >= 0.9. The highest density obtained in L-mode discharges was 3 × n^GW_max. Implications of these results for ITER will be discussed.

The Characterization of Feces and Urine: A Review of the Literature to Inform Advanced Treatment Technology

PubMed Central

Rose, C.; Parker, A.; Jefferson, B.; Cartmell, E.

2015-01-01

The safe disposal of human excreta is of paramount importance for the health and welfare of populations living in low income countries as well as the prevention of pollution to the surrounding environment. On-site sanitation (OSS) systems are the most numerous means of treating excreta in low income countries, these facilities aim at treating human waste at source and can provide a hygienic and affordable method of waste disposal. However, current OSS systems need improvement and require further research and development. Development of OSS facilities that treat excreta at, or close to, its source require knowledge of the waste stream entering the system. Data regarding the generation rate and the chemical and physical composition of fresh feces and urine was collected from the medical literature as well as the treatability sector. The data were summarized and statistical analysis was used to quantify the major factors that were a significant cause of variability. The impact of this data on biological processes, thermal processes, physical separators, and chemical processes was then assessed. Results showed that the median fecal wet mass production was 128 g/cap/day, with a median dry mass of 29 g/cap/day. Fecal output in healthy individuals was 1.20 defecations per 24 hr period and the main factor affecting fecal mass was the fiber intake of the population. Fecal wet mass values were increased by a factor of 2 in low income countries (high fiber intakes) in comparison to values found in high income countries (low fiber intakes). Feces had a median pH of 6.64 and were composed of 74.6% water. Bacterial biomass is the major component (25–54% of dry solids) of the organic fraction of the feces. Undigested carbohydrate, fiber, protein, and fat comprise the remainder and the amounts depend on diet and diarrhea prevalence in the population. The inorganic component of the feces is primarily undigested dietary elements that also depend on dietary supply. Median urine generation rates were 1.42 L/cap/day with a dry solids content of 59 g/cap/day. Variation in the volume and composition of urine is caused by differences in physical exertion, environmental conditions, as well as water, salt, and high protein intakes. Urine has a pH 6.2 and contains the largest fractions of nitrogen, phosphorus, and potassium released from the body. The urinary excretion of nitrogen was significant (10.98 g/cap/day) with urea the most predominant constituent making up over 50% of total organic solids. The dietary intake of food and fluid is the major cause of variation in both the fecal and urine composition and these variables should always be considered if the generation rate, physical, and chemical composition of feces and urine is to be accurately predicted. PMID:26246784

The scientific argumentation profile of physics teacher candidate in Surabaya

NASA Astrophysics Data System (ADS)

Ain, T. N.; Wibowo, H. A. C.; Rohman, A.; Deta, U. A.

2018-03-01

The ability of scientific argumentation is an essential factor that must be mastered by physics teacher candidate as a requirement in explaining good and accurate scientific concepts. In the process of arguing, students develop explanations or persuade colleagues to support their hypotheses, express doubts, ask questions, relate alternative answers, and confirm what is unknown to develop the ability to provide rational and scientific explanations. The design of this research is descriptive qualitative with the subject of research is 20 undergraduate students of Physics Education Department in Surabaya. The research instrument consists of four casuistic questions related to the concept of kinematics. The argumentation pattern of physics teacher candidate is coded using Toulmin's argumentation pattern. The results show that the student’s ability in providing scientific argument is at the level of providing claims with the support of a weak warrant. The students are not able to provide excellent rebuttals. In each case given, the student can give a good claim statement in answering the questions. However, the concept used to support the claim is not correct. This case causes the warrant used to support the claim is weak. Students also do not analyse other facts that affect the system. Students have not reached a higher level because the understanding of physics is not deep enough.

Risk Management and Physical Modelling for Mountainous Natural Hazards

NASA Astrophysics Data System (ADS)

Lehning, Michael; Wilhelm, Christian

Population growth and climate change cause rapid changes in mountainous regions resulting in increased risks of floods, avalanches, debris flows and other natural hazards. Xevents are of particular concern, since attempts to protect against them result in exponentially growing costs. In this contribution, we suggest an integral risk management approach to dealing with natural hazards that occur in mountainous areas. Using the example of a mountain pass road, which can be protected from the danger of an avalanche by engineering (galleries) and/or organisational (road closure) measures, we show the advantage of an optimal combination of both versus the traditional approach, which is to rely solely on engineering structures. Organisational measures become especially important for Xevents because engineering structures cannot be designed for those events. However, organisational measures need a reliable and objective forecast of the hazard. Therefore, we further suggest that such forecasts should be developed using physical numerical modelling. We present the status of current approaches to using physical modelling to predict snow cover stability for avalanche warnings and peak runoff from mountain catchments for flood warnings. While detailed physical models can already predict peak runoff reliably, they are only used to support avalanche warnings. With increased process knowledge and computer power, current developments should lead to a enhanced role for detailed physical models in natural mountain hazard prediction.

Spanish validation of the Exercise Therapy Burden Questionnaire (ETBQ) for the assessment of barriers associated to doing physical therapy for the treatment of chronic illness.

PubMed

Navarro-Albarracín, César; Poiraudeau, Serge; Chico-Matallana, Noelia; Vergara-Martín, Jesús; Martin, William; Castro-Sánchez, Adelaida María; Matarán-Peñarrocha, Guillermo A

2018-06-08

To validate the Spanish version of the Exercise Therapy Burden Questionnaire (ETBQ) for the assessment of barriers associated to doing physical therapy for the treatment of chronic ailments. A sample of 177 patients, 55.93% men and 44.07% women, with an average age of 51.03±14.91 was recruited. The reliability of the questionnaire was tested with Cronbach's alpha coefficient, and the validity of the instrument was assessed through the divergent validation process and factor analysis. The factor analysis was different to the original questionnaire, composed of a dimension, in this case determined three dimensions: (1) General limitations for doing physical exercise. (2) Physical limitations for doing physical exercise. (3) Limitations caused by the patients' predisposition to their exercises. The reliability of the test-retest was measured through the intraclass correlation coefficient (ICC) and the Bland-Altman plot. Cronbach's alpha was 0.8715 for the total ETBQ. The ICC of the test-retest was 0.745 and the Bland-Altman plot showed no systematic trend. We have obtained the translated version in Spanish of the ETBQ questionnaire. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Effects of preparation steps on the physical parameters and electromechanical properties of IPMC actuators

NASA Astrophysics Data System (ADS)

Wang, Yanjie; Zhu, Zicai; Chen, Hualing; Luo, Bin; Chang, Longfei; Wang, Yongquan; Li, Dichen

2014-12-01

The electromechanical properties of ionic polymer-metal composites (IPMC) are affected by many factors, including resistivity of surface electrodes, bending stiffness and dielectric modulus, etc, which are closely related to physical and chemical preparation steps. This paper focuses on the effects of preparation steps on these physical parameters and electromechanical properties of IPMC actuators. The mechanisms of electrode formation in the preparation steps are also clarified and investigated. To obtain samples with different features, one or more of the crucial process steps, including pretreatment, impregnation-reduction and chemical plating, were selected to fabricate IPMC. The experimental observations revealed that the physical parameters of IPMC strongly depend on their electrode morphologies caused by different steps, which were reasonable from the standpoint of physics. IPMC with the characteristics of low surface resistance and low bending stiffness, and a large area of interface electrode exhibits a perfect performance. The improvements were considered to be attributed to the double-layer electrostatic effect, induced by the broad dispersion of penetrated electrode nanoparticles. An electrical component, consisting of an equivalent circuit of a parallel combination of the serial circuit of the resistance and the electric double-layer capacitance, is introduced to qualitatively explain the deformation behaviors of IPMC. This research helps to improve the preparation steps and promote the understanding of IPMC.

2D and 3D virtual interactive laboratories of physics on Unity platform

NASA Astrophysics Data System (ADS)

González, J. D.; Escobar, J. H.; Sánchez, H.; De la Hoz, J.; Beltrán, J. R.

2017-12-01

Using the cross-platform game engine Unity, we develop virtual laboratories for PC, consoles, mobile devices and website as an innovative tool to study physics. There is extensive uptake of ICT in the teaching of science and its impact on the learning, and considering the limited availability of laboratories for physics teaching and the difficulties this causes in the learning of school students, we design the virtual laboratories to enhance studentâĂŹs knowledge of concepts in physics. To achieve this goal, we use Unity due to provide support bump mapping, reflection mapping, parallax mapping, dynamics shadows using shadows maps, full-screen post-processing effects and render-to-texture. Unity can use the best variant for the current video hardware and, if none are compatible, to use an alternative shader that may sacrifice features for performance. The control over delivery to mobile devices, web browsers, consoles and desktops is the main reason Unity is the best option among the same kind cross-platform. Supported platforms include Android, Apple TV, Linux, iOS, Nintendo 3DS line, macOS, PlayStation 4, Windows Phone 8, Wii but also an asset server and Nvidia’s PhysX physics engine which is the most relevant tool on Unity for our PhysLab.

Radiation processing of minimally processed vegetables and aromatic plants

NASA Astrophysics Data System (ADS)

Trigo, M. J.; Sousa, M. B.; Sapata, M. M.; Ferreira, A.; Curado, T.; Andrada, L.; Botelho, M. L.; Veloso, M. G.

2009-07-01

Vegetables are an essential part of people's diet all around the world. Due to cultivate techniques and handling after harvest, these products, may contain high microbial load that can cause food borne outbreaks. The irradiation of minimally processed vegetables is an efficient way to reduce the level of microorganisms and to inhibit parasites, helping a safe global trade. Evaluation of the irradiation's effects was carried out in minimal processed vegetables, as coriander ( Coriandrum sativum L .), mint ( Mentha spicata L.), parsley ( Petroselinum crispum Mill, (A.W. Hill)), lettuce ( Lactuca sativa L.) and watercress ( Nasturium officinale L.). The inactivation level of natural microbiota and the D 10 values of Escherichia coli O157:H7 and Listeria innocua in these products were determined. The physical-chemical and sensorial characteristics before and after irradiation at a range of 0.5 up to 2.0 kGy applied doses were also evaluated. No differences were verified in the overall of sensorial and physical properties after irradiation up to 1 kGy, a decrease of natural microbiota was noticed (⩾2 log). Based on the determined D10, the amount of radiation necessary to kill 10 5E. coli and L. innocua was between 0.70 and 1.55 kGy. Shelf life of irradiated coriander, mint and lettuce at 0.5 kGy increased 2, 3 and 4 days, respectively, when compared with non-irradiated.

Fundamental Physics

NASA Image and Video Library

2003-01-22

Still photographs taken over 16 hours on Nov. 13, 2001, on the International Space Station have been condensed into a few seconds to show the de-mixing -- or phase separation -- process studied by the Experiment on Physics of Colloids in Space. Commanded from the ground, dozens of similar tests have been conducted since the experiment arrived on ISS in 2000. The sample is a mix of polymethylmethacrylate (PMMA or acrylic) colloids, polystyrene polymers and solvents. The circular area is 2 cm (0.8 in.) in diameter. The phase separation process occurs spontaneously after the sample is mechanically mixed. The evolving lighter regions are rich in colloid and have the structure of a liquid. The dark regions are poor in colloids and have the structure of a gas. This behavior carnot be observed on Earth because gravity causes the particles to fall out of solution faster than the phase separation can occur. While similar to a gas-liquid phase transition, the growth rate observed in this test is different from any atomic gas-liquid or liquid-liquid phase transition ever measured experimentally. Ultimately, the sample separates into colloid-poor and colloid-rich areas, just as oil and vinegar separate. The fundamental science of de-mixing in this colloid-polymer sample is the same found in the annealing of metal alloys and plastic polymer blends. Improving the understanding of this process may lead to improving processing of these materials on Earth.

The submarine volcano eruption at the island of El Hierro: physical-chemical perturbation and biological response

PubMed Central

Fraile-Nuez, E.; González-Dávila, M.; Santana-Casiano, J. M.; Arístegui, J.; Alonso-González, I. J.; Hernández-León, S.; Blanco, M. J.; Rodríguez-Santana, A.; Hernández-Guerra, A.; Gelado-Caballero, M. D.; Eugenio, F.; Marcello, J.; de Armas, D.; Domínguez-Yanes, J. F.; Montero, M. F.; Laetsch, D. R.; Vélez-Belchí, P.; Ramos, A.; Ariza, A. V.; Comas-Rodríguez, I.; Benítez-Barrios, V. M.

2012-01-01

On October 10 2011 an underwater eruption gave rise to a novel shallow submarine volcano south of the island of El Hierro, Canary Islands, Spain. During the eruption large quantities of mantle-derived gases, solutes and heat were released into the surrounding waters. In order to monitor the impact of the eruption on the marine ecosystem, periodic multidisciplinary cruises were carried out. Here, we present an initial report of the extreme physical-chemical perturbations caused by this event, comprising thermal changes, water acidification, deoxygenation and metal-enrichment, which resulted in significant alterations to the activity and composition of local plankton communities. Our findings highlight the potential role of this eruptive process as a natural ecosystem-scale experiment for the study of extreme effects of global change stressors on marine environments. PMID:22768379

The physical chemistry and materials science behind sinter-resistant catalysts.

PubMed

Dai, Yunqian; Lu, Ping; Cao, Zhenming; Campbell, Charles T; Xia, Younan

2018-06-18

Catalyst sintering, a main cause of the loss of catalytic activity and/or selectivity at high reaction temperatures, is a major concern and grand challenge in the general area of heterogeneous catalysis. Although all heterogeneous catalysts are inevitably subjected to sintering during their operation, the immediate and drastic consequences can be mitigated by carefully engineering the catalytic particles and their interactions with the supports. In this tutorial review, we highlight recent progress in understanding the physical chemistry and materials science involved in sintering, including the discussion of advanced techniques, such as in situ microscopy and spectroscopy, for investigating the sintering process and its rate. We also discuss strategies for the design and rational fabrication of sinter-resistant catalysts. Finally, we showcase recent success in improving the thermal stability and thus sinter resistance of supported catalytic systems.

PROCESS OF PHYSICAL DISABILITY AMONG OLDER ADULTS―CONTRIBUTION OF FRAILTY IN THE SUPER-AGED SOCIETY

PubMed Central

KUZUYA, MASAFUMI

2012-01-01

ABSTRACT One of the critical issues that Japan, well known for the world’s highest proportion of older adults, a super-aged society, is currently confronting is how to prevent physical disability in old age. This issue is particularly important not only from a medical perspective such as functional prognoses but also from a socio-economic angle in view of reducing the rapid rise in the cost of medical and long-term care insurance services. Functional decline in old age results not only from acute diseases but also from frailty. Such a common and important syndrome that is increasingly prevalent with advancing age can be the cause. The present article intends to review what is known about frailty, including its definition, epidemiology, and pathophysiology, and to examine potential areas of future research. PMID:22515109

Presence of Li clusters in molten LiCl-Li

DOE PAGES

Merwin, Augustus; Phillips, William C.; Williamson, Mark A.; ...

2016-05-05

Molten mixtures of lithium chloride and metallic lithium are of significant interest in various metal oxide reduction processes. These solutions have been reported to exhibit seemingly anomalous physical characteristics that lack a comprehensive explanation. ln the current work, the physical chemistry of molten solutions of lithium chloride and metallic lithium, with and without lithium oxide, was investigated using in situ Raman spectroscopy. The Raman spectra obtained from these solutions were in agreement with the previously reported spectrum of the lithium cluster, Li 8. Furthermore, this observation is indicative of a nanofluid type colloidal suspension of Li 8, in a moltenmore » salt matrix. It is suggested that the formation and suspension of lithium clusters in lithium chloride is the cause of various phenomena exhibited by these solutions that were previously unexplainable.« less

Abiotic and Biotic Degradation of Oxo-Biodegradable Plastic Bags by Pleurotus ostreatus

PubMed Central

da Luz, José Maria Rodrigues; Paes, Sirlaine Albino; Bazzolli, Denise Mara Soares; Tótola, Marcos Rogério; Demuner, Antônio Jacinto; Kasuya, Maria Catarina Megumi

2014-01-01

In this study, we evaluated the growth of Pleurotus ostreatus PLO6 using oxo-biodegradable plastics as a carbon and energy source. Oxo-biodegradable polymers contain pro-oxidants that accelerate their physical and biological degradation. These polymers were developed to decrease the accumulation of plastic waste in landfills. To study the degradation of the plastic polymers, oxo-biodegradable plastic bags were exposed to sunlight for up to 120 days, and fragments of these bags were used as substrates for P. ostreatus. We observed that physical treatment alone was not sufficient to initiate degradation. Instead, mechanical modifications and reduced titanium oxide (TiO2) concentrations caused by sunlight exposure triggered microbial degradation. The low specificity of lignocellulolytic enzymes and presence of endomycotic nitrogen-fixing microorganisms were also contributing factors in this process. PMID:25419675

Climate change and physical disturbance cause similar community shifts in biological soil crusts.

PubMed

Ferrenberg, Scott; Reed, Sasha C; Belnap, Jayne

2015-09-29

Biological soil crusts (biocrusts)—communities of mosses, lichens, cyanobacteria, and heterotrophs living at the soil surface—are fundamental components of drylands worldwide, and destruction of biocrusts dramatically alters biogeochemical processes, hydrology, surface energy balance, and vegetation cover. Although there has been long-standing concern over impacts of physical disturbances on biocrusts (e.g., trampling by livestock, damage from vehicles), there is increasing concern over the potential for climate change to alter biocrust community structure. Using long-term data from the Colorado Plateau, we examined the effects of 10 y of experimental warming and altered precipitation (in full-factorial design) on biocrust communities and compared the effects of altered climate with those of long-term physical disturbance (>10 y of replicated human trampling). Surprisingly, altered climate and physical disturbance treatments had similar effects on biocrust community structure. Warming, altered precipitation frequency [an increase of small (1.2 mm) summer rainfall events], and physical disturbance from trampling all promoted early successional community states marked by dramatic declines in moss cover and increases in cyanobacteria cover, with more variable effects on lichens. Although the pace of community change varied significantly among treatments, our results suggest that multiple aspects of climate change will affect biocrusts to the same degree as physical disturbance. This is particularly disconcerting in the context of warming, as temperatures for drylands are projected to increase beyond those imposed as treatments in our study.

Statistical physics of human beings in games: Controlled experiments

NASA Astrophysics Data System (ADS)

Liang, Yuan; Huang, Ji-Ping

2014-07-01

It is important to know whether the laws or phenomena in statistical physics for natural systems with non-adaptive agents still hold for social human systems with adaptive agents, because this implies whether it is possible to study or understand social human systems by using statistical physics originating from natural systems. For this purpose, we review the role of human adaptability in four kinds of specific human behaviors, namely, normal behavior, herd behavior, contrarian behavior, and hedge behavior. The approach is based on controlled experiments in the framework of market-directed resource-allocation games. The role of the controlled experiments could be at least two-fold: adopting the real human decision-making process so that the system under consideration could reflect the performance of genuine human beings; making it possible to obtain macroscopic physical properties of a human system by tuning a particular factor of the system, thus directly revealing cause and effect. As a result, both computer simulations and theoretical analyses help to show a few counterparts of some laws or phenomena in statistical physics for social human systems: two-phase phenomena or phase transitions, entropy-related phenomena, and a non-equilibrium steady state. This review highlights the role of human adaptability in these counterparts, and makes it possible to study or understand some particular social human systems by means of statistical physics coming from natural systems.

Physical Restraint Initiation in Nursing Homes and Subsequent Resident Health

ERIC Educational Resources Information Center

Engberg, John; Castle, Nicholas G.; McCaffrey, Daniel

2008-01-01

Purpose: It is widely believed that physical restraint use causes mental and physical health decline in nursing home residents. Yet few studies exist showing an association between restraint initiation and health decline. In this research, we examined whether physical restraint initiation is associated with subsequent lower physical or mental…

Depletion of key protein components of the RISC pathway impairs pre-ribosomal RNA processing.

PubMed

Liang, Xue-Hai; Crooke, Stanley T

2011-06-01

Little is known about whether components of the RNA-induced silencing complex (RISC) mediate the biogenesis of RNAs other than miRNA. Here, we show that depletion of key proteins of the RISC pathway by antisense oligonucleotides significantly impairs pre-rRNA processing in human cells. In cells depleted of Drosha or Dicer, different precursors to 5.8S rRNA strongly accumulated, without affecting normal endonucleolytic cleavages. Moderate yet distinct processing defects were also observed in Ago2-depleted cells. Physical links between pre-rRNA and these proteins were identified by co-immunoprecipitation analyses. Interestingly, simultaneous depletion of Dicer and Drosha led to a different processing defect, causing slower production of 28S rRNA and its precursor. Both Dicer and Ago2 were detected in the nuclear fraction, and reduction of Dicer altered the structure of the nucleolus, where pre-rRNA processing occurs. Together, these results suggest that Drosha and Dicer are implicated in rRNA biogenesis.

Impact of very low physical activity, BMI, and comorbidities on mortality among breast cancer survivors

PubMed Central

Nelson, Sandahl H; Marinac, Catherine R; Patterson, Ruth E; Nechuta, Sarah J; Flatt, Shirley W; Caan, Bette J; Kwan, Marilyn L; Poole, Elizabeth M.; Chen, Wendy Y; Shu, Xiao-ou; Pierce, John P

2016-01-01

Purpose To examine post diagnosis BMI, very low physical activity, and comorbidities, as predictors of breast cancer specific and all-cause mortality. Methods Data from three female US breast cancer survivor cohorts were harmonized in the After Breast Cancer Pooling Project (n=9513). Delayed entry Cox proportional hazards models were used to examine the impact of three post-diagnosis lifestyle factors; body mass index (BMI), select comorbidities (diabetes only, hypertension only, or both) and very low physical activity (defined as physical activity <1.5 MET hrs/wk) in individual models and together in multivariate models for breast cancer and all-cause mortality. Results For breast cancer mortality, the individual lifestyle models demonstrated a significant association with very low physical activity but not with the selected comorbidities or BMI. In the model that included all three lifestyle variables, very low physical activity was associated with a 22% increased risk of breast cancer mortality (HR=1.22, 95% CI= 1.05, 1.42). For all-cause mortality, the three individual models demonstrated significant associations for all three lifestyle predictors. In the combined model, the strength and significance of the association of comorbidities (both hypertension and diabetes vs. neither: HR=2.16, 95% CI= 1.79, 2.60) and very low physical activity (HR=1.35, 95% CI= 1.22, 1.51) remained unchanged, but the association with obesity was completely attenuated. Conclusion These data indicate that after active treatment, very low physical activity, consistent with a sedentary lifestyle (and comorbidities for all-cause mortality), may account for the increased risk of mortality, with higher BMI, that is seen in other studies. PMID:26861056

KSC-98pc1131

NASA Image and Video Library

1998-09-18

KENNEDY SPACE CENTER, FLA. -- The Spartan solar-observing deployable spacecraft is lifted from its work stand to move it to a payload canister in the Multi-Payload Processing Facility at KSC. Spartan is one of the payloads for the STS-95 mission, scheduled to launch Oct. 29. Spartan is a solar physics spacecraft designed to perform remote sensing of the hot outer layers of the sun's atmosphere or corona. The objective of the observations is to investigate the mechanisms causing the heating of the solar corona and the acceleration of the solar wind which originates in the corona. Other research payloads include the Hubble Space Telescope Orbital Systems Test Platform, the International Extreme Ultraviolet Hitchhiker, and the SPACEHAB single module with experiments on space flight and the aging process

Grain boundary oxidation and its effects on high temperature fatigue life

NASA Technical Reports Server (NTRS)

Liu, H. W.; Oshida, Yoshiki

1986-01-01

Fatigue lives at elevated temperatures are often shortened by creep and/or oxidation. Creep causes grain boundary void nucleation and grain boundary cavitation. Grain boundary voids and cavities will accelerate fatigue crack nucleation and propagation, and thereby shorten fatigue life. The functional relationships between the damage rate of fatigue crack nucleation and propagation and the kinetic process of oxygen diffusion depend on the detailed physical processes. The kinetics of grain boundary oxidation penetration was investigated. The statistical distribution of grain boundary penetration depth was analyzed. Its effect on high temperature fatigue life are discussed. A model of intermittent micro-ruptures of grain boundary oxide was proposed for high temperature fatigue crack growth. The details of these studies are reported.

Dislocation-Twin Boundary Interactions Induced Nanocrystalline via SPD Processing in Bulk Metals

NASA Astrophysics Data System (ADS)

Zhang, Fucheng; Feng, Xiaoyong; Yang, Zhinan; Kang, Jie; Wang, Tiansheng

2015-03-01

This report investigated dislocation-twin boundary (TB) interactions that cause the TB to disappear and turn into a high-angle grain boundary (GB). The evolution of the microstructural characteristics of Hadfield steel was shown as a function of severe plastic deformation processing time. Sessile Frank partial dislocations and/or sessile unit dislocations were formed on the TB through possible dislocation reactions. These reactions induced atomic steps on the TB and led to the accumulation of gliding dislocations at the TB, which resulted in the transition from coherent TB to incoherent GB. The factors that affect these interactions were described, and a physical model was established to explain in detail the feasible dislocation reactions at the TB.

Dislocation–Twin Boundary Interactions Induced Nanocrystalline via SPD Processing in Bulk Metals

PubMed Central

Zhang, Fucheng; Feng, Xiaoyong; Yang, Zhinan; Kang, Jie; Wang, Tiansheng

2015-01-01

This report investigated dislocation–twin boundary (TB) interactions that cause the TB to disappear and turn into a high-angle grain boundary (GB). The evolution of the microstructural characteristics of Hadfield steel was shown as a function of severe plastic deformation processing time. Sessile Frank partial dislocations and/or sessile unit dislocations were formed on the TB through possible dislocation reactions. These reactions induced atomic steps on the TB and led to the accumulation of gliding dislocations at the TB, which resulted in the transition from coherent TB to incoherent GB. The factors that affect these interactions were described, and a physical model was established to explain in detail the feasible dislocation reactions at the TB. PMID:25757550

Dislocation-twin boundary interactions induced nanocrystalline via SPD processing in bulk metals.

PubMed

Zhang, Fucheng; Feng, Xiaoyong; Yang, Zhinan; Kang, Jie; Wang, Tiansheng

2015-03-11

This report investigated dislocation-twin boundary (TB) interactions that cause the TB to disappear and turn into a high-angle grain boundary (GB). The evolution of the microstructural characteristics of Hadfield steel was shown as a function of severe plastic deformation processing time. Sessile Frank partial dislocations and/or sessile unit dislocations were formed on the TB through possible dislocation reactions. These reactions induced atomic steps on the TB and led to the accumulation of gliding dislocations at the TB, which resulted in the transition from coherent TB to incoherent GB. The factors that affect these interactions were described, and a physical model was established to explain in detail the feasible dislocation reactions at the TB.

Man-caused seismicity of Kuzbass

NASA Astrophysics Data System (ADS)

Emanov, Alexandr; Emanov, Alexey; Leskova, Ekaterina; Fateyev, Alexandr

2010-05-01

A natural seismicity of Kuznetsk Basin is confined in the main to mountain frame of Kuznetsk hollow. In this paper materials of experimental work with local station networks within sediment basin are presented. Two types of seismicity display within Kuznetsk hollow have been understood: first, man-caused seismic processes, confined to mine working and concentrated on depths up to one and a half of km; secondly, seismic activations on depths of 2-56 km, not coordinated in plan with coal mines. Every of studied seismic activations consists of large quantity of earthquakes of small powers (Ms=1-3). From one to first tens of earthquakes were recorded in a day. The earthquakes near mine working shift in space along with mine working, and seismic process become stronger at the instant a coal-plough machine is operated, and slacken at the instant the preventive works are executed. The seismic processes near three lavas in Kuznetsk Basin have been studied in detail. Uplift is the most typical focal mechanism. Activated zone near mine working reach in diameter 1-1,5 km. Seismic activations not linked with mine working testify that the subsoil of Kuznetsk hollow remain in stress state in whole. The most probable causes of man-caused action on hollow are processes, coupled with change of physical state of rocks at loss of methane from large volume or change by mine working of rock watering in large volume. In this case condensed rocks, lost gas and water, can press out upwards, realizing the reverse fault mechanism of earthquakes. A combination of stress state of hollow with man-caused action at deep mining may account for incipient activations in Kuznetsk Basin. Today earthquakes happen mainly under mine workings, though damages of workings themselves do not happen, but intensive shaking on surface calls for intent study of so dangerous phenomena. In 2009 replicates of the experiment on research of seismic activations in area of before investigated lavas have been conducted. A spatial displacement of activations along with mine working has been found. An impact of technogeneous factors on behavior of seismic process was investigated. It was demonstrated that industrial explosions in neighboring open-casts have no pronounced effect on seismic process near lavas. Stoppage of mole work in lavas leads to simultaneous changes in man-caused seismicity. The number of technogeneous earthquakes is halved. The earthquakes of small powers remain, but such slack lead to occasional though more strong technogeneous earthquakes.

Approach to Emergencies in Schizophrenia in University Hospital "Vrapče".

PubMed

Silić, Ante; Savić, Aleksandar; Čulo, Ilaria; Kos, Suzana; Vukojević, Jakša; Brumen, Daška; Ostojić, DraŽenka

2018-06-01

An emergency in psychiatric setting is any disorder in thought process, feelings and/or behavior of the patient that requires urgent therapeutic intervention. In general, we can observe an increase in numbers of psychiatric emergencies throughout the world and in Croatia as well. Agitation and aggression are one of the most common causes of emergency in psychiatry. Agitation is common and frequent in patients suffering from schizophrenia. Patient can be agitated in various levels such as: mild, moderate or severe and can alternate between these levels in the same presentation. Agitated patients often require hospitalization that includes pharmacotherapy and sometimes physical restraining, in order to treat the cause of agitation and prevent auto and/or heterodestructive behavior. In this paper we focus on patients suffering from schizophrenia that were admitted in University Hospital "Vrapče" in 2017, and assess the numbers through the criteria of voluntary vs. involuntary admissions and physical restraint usage. Out of total observations, 130 (35.6%) were patients admitted for the first time and 179 (49%) were patients later diagnosed with schizophrenia spectrum and other psychotic disorders. Court ordered involuntary hospitalization was ordered for 35 (2.8%) patients out of total admitted patients, and 68.6% (N24) of them were diagnosed with schizophrenia spectrum and other psychotic disorders. Physical restraint was used for 122 patients out of total admissions and 28.7% (N35) of restrained patients were diagnosed with schizophrenia spectrum and other psychotic disorders. Emergencies in patient suffering from schizophrenia are extremely delicate and demanding situations in every-day clinical practice of psychiatrist. There is an increased risk involved for the patient but for the staff as well. All interventions should be individualized and patient should carefully monitored throughout the entire process. All professionals involved in care for a patient should be up to date with medical and legal issues.

A review of the physics and response models for burnout of semiconductor devices

NASA Astrophysics Data System (ADS)

Orvis, W. J.; Khanaka, G. H.; Yee, J. H.

1984-12-01

Physical mechanisms that cause semiconductor devices to fail from electrical overstress--particularly, EMP-induced electrical stress--are described in light of the current literature and the authors' own research. A major concern is the cause and effects of second breakdown phenomena in p-n junction devices. Models of failure thresholds are evaluated for their inherent errors and for their ability to represent the relevant physics. Finally, the response models that relate electromagnetic stress parameters to appropriate failure-threshold parameters are discussed.

Improvement of Meteorological Inputs for TexAQS-II Air Quality Simulations

NASA Astrophysics Data System (ADS)

Ngan, F.; Byun, D.; Kim, H.; Cheng, F.; Kim, S.; Lee, D.

2008-12-01

An air quality forecasting system (UH-AQF) for Eastern Texas, which is in operation by the Institute for Multidimensional Air Quality Studies (IMAQS) at the University of Houston, uses the Fifth-Generation PSU/NCAR Mesoscale Model MM5 model as the meteorological driver for modeling air quality with the Community Multiscale Air Quality (CMAQ) model. While the forecasting system was successfully used for the planning and implementation of various measurement activities, evaluations of the forecasting results revealed a few systematic problems in the numerical simulations. From comparison with observations, we observe some times over-prediction of northerly winds caused by inaccurate synoptic inputs and other times too strong southerly winds caused by local sea breeze development. Discrepancies in maximum and minimum temperature are also seen for certain days. Precipitation events, as well as clouds, are simulated at the incorrect locations and times occasionally. Model simulatednrealistic thunderstorms are simulated, causing sometimes cause unrealistically strong outflows. To understand physical and chemical processes influencing air quality measures, a proper description of real world meteorological conditions is essential. The objective of this study is to generate better meteorological inputs than the AQF results to support the chemistry modeling. We utilized existing objective analysis and nudging tools in the MM5 system to develop the MUltiscale Nest-down Data Assimilation System (MUNDAS), which incorporates extensive meteorological observations available in the simulated domain for the retrospective simulation of the TexAQS-II period. With the re-simulated meteorological input, we are able to better predict ozone events during TexAQS-II period. In addition, base datasets in MM5 such as land use/land cover, vegetation fraction, soil type and sea surface temperature are updated by satellite data to represent the surface features more accurately. They are key physical parameters inputs affecting transfer of heat, momentum and soil moisture in land-surface process in MM5. Using base the accurate input datasets, we are able to have improved see the differences of predictions of ground temperatures, winds and even thunderstorm activities within boundary layer.

How Does Physical Activity Help Build Healthy Bones?

MedlinePlus

... Share Facebook Twitter Pinterest Email Print How does physical activity help build healthy bones? Bones are living tissue. Weight-bearing physical activity causes new bone tissue to form, and this ...

Reversibility and energy dissipation in adiabatic superconductor logic.

PubMed

Takeuchi, Naoki; Yamanashi, Yuki; Yoshikawa, Nobuyuki

2017-03-06

Reversible computing is considered to be a key technology to achieve an extremely high energy efficiency in future computers. In this study, we investigated the relationship between reversibility and energy dissipation in adiabatic superconductor logic. We analyzed the evolution of phase differences of Josephson junctions in the reversible quantum-flux-parametron (RQFP) gate and confirmed that the phase differences can change time reversibly, which indicates that the RQFP gate is physically, as well as logically, reversible. We calculated energy dissipation required for the RQFP gate to perform a logic operation and numerically demonstrated that the energy dissipation can fall below the thermal limit, or the Landauer bound, by lowering operation frequencies. We also investigated the 1-bit-erasure gate as a logically irreversible gate and the quasi-RQFP gate as a physically irreversible gate. We calculated the energy dissipation of these irreversible gates and showed that the energy dissipation of these gate is dominated by non-adiabatic state changes, which are induced by unwanted interactions between gates due to logical or physical irreversibility. Our results show that, in reversible computing using adiabatic superconductor logic, logical and physical reversibility are required to achieve energy dissipation smaller than the Landauer bound without non-adiabatic processes caused by gate interactions.

Finding the Root Causes of Statistical Inconsistency in Community Earth System Model Output

NASA Astrophysics Data System (ADS)

Milroy, D.; Hammerling, D.; Baker, A. H.

2017-12-01

Baker et al (2015) developed the Community Earth System Model Ensemble Consistency Test (CESM-ECT) to provide a metric for software quality assurance by determining statistical consistency between an ensemble of CESM outputs and new test runs. The test has proved useful for detecting statistical difference caused by compiler bugs and errors in physical modules. However, detection is only the necessary first step in finding the causes of statistical difference. The CESM is a vastly complex model comprised of millions of lines of code which is developed and maintained by a large community of software engineers and scientists. Any root cause analysis is correspondingly challenging. We propose a new capability for CESM-ECT: identifying the sections of code that cause statistical distinguishability. The first step is to discover CESM variables that cause CESM-ECT to classify new runs as statistically distinct, which we achieve via Randomized Logistic Regression. Next we use a tool developed to identify CESM components that define or compute the variables found in the first step. Finally, we employ the application Kernel GENerator (KGEN) created in Kim et al (2016) to detect fine-grained floating point differences. We demonstrate an example of the procedure and advance a plan to automate this process in our future work.

Mudslide and/or animal attack are more plausible causes and circumstances of death for AL 288 ('Lucy'): A forensic anthropology analysis.

PubMed

Charlier, Phillippe; Coppens, Yves; Augias, Anaïs; Deo, Saudamini; Froesch, Philippe; Huynh-Charlier, Isabelle

2018-01-01

Following a global morphological and micro-CT scan examination of the original and cast of the skeleton of Australopithecus afarensis AL 288 ('Lucy'), Kappelman et al. have recently proposed a diagnosis of a fall from a significant height (a tree) as a cause of her death. According to topographical data from the discovery site, complete re-examination of a high-quality resin cast of the whole skeleton and forensic experience, we propose that the physical process of a vertical deceleration cannot be the only cause for her observed injuries. Two different factors were involved: rolling and multiple impacts in the context of a mudslide and an animal attack with bite marks, multi-focal fractures and violent movement of the body. It is important to consider a differential diagnosis of the observed fossil lesions because environmental factors should not be excluded in this ancient archaeological context as with any modern forensic anthropological case.

Maternal segmental disomy in Leigh syndrome with cytochrome c oxidase deficiency caused by homozygous SURF1 mutation.

PubMed

van Riesen, A K J; Antonicka, H; Ohlenbusch, A; Shoubridge, E A; Wilichowski, E K G

2006-04-01

Cytochrome c oxidase deficiency (COX) is the most frequent cause of Leigh syndrome (LS), a mitochondrial subacute necrotizing encephalomyelopathy. Most of these LS (COX-) patients show mutations in SURF1 on chromosome 9 (9q34), which encodes a protein essential for the assembly of the COX complex. We describe a family whose first-born boy developed characteristic features of LS. Severe COX deficiency in muscle was caused by a novel homozygous nonsense mutation in SURF1. Segregation analysis of this mutation in the family was incompatible with autosomal recessive inheritance but consistent with a maternal disomy. Haplotype analysis of microsatellite markers confirmed isodisomy involving nearly the complete long arm of chromosome 9 (9q21-9tel). No additional physical abnormalities were present in the boy, suggesting that there are no imprinted genes on the long arm of chromosome 9 which are crucial for developmental processes. This case of segmental isodisomy illustrates that genotyping of parents is crucial for correct genetic counseling.

Clustering of arc volcanoes caused by temperature perturbations in the back-arc mantle

PubMed Central

Lee, Changyeol; Wada, Ikuko

2017-01-01

Clustering of arc volcanoes in subduction zones indicates along-arc variation in the physical condition of the underlying mantle where majority of arc magmas are generated. The sub-arc mantle is brought in from the back-arc largely by slab-driven mantle wedge flow. Dynamic processes in the back-arc, such as small-scale mantle convection, are likely to cause lateral variations in the back-arc mantle temperature. Here we use a simple three-dimensional numerical model to quantify the effects of back-arc temperature perturbations on the mantle wedge flow pattern and sub-arc mantle temperature. Our model calculations show that relatively small temperature perturbations in the back-arc result in vigorous inflow of hotter mantle and subdued inflow of colder mantle beneath the arc due to the temperature dependence of the mantle viscosity. This causes a three-dimensional mantle flow pattern that amplifies the along-arc variations in the sub-arc mantle temperature, providing a simple mechanism for volcano clustering. PMID:28660880

Clustering of arc volcanoes caused by temperature perturbations in the back-arc mantle.

PubMed

Lee, Changyeol; Wada, Ikuko

2017-06-29

Clustering of arc volcanoes in subduction zones indicates along-arc variation in the physical condition of the underlying mantle where majority of arc magmas are generated. The sub-arc mantle is brought in from the back-arc largely by slab-driven mantle wedge flow. Dynamic processes in the back-arc, such as small-scale mantle convection, are likely to cause lateral variations in the back-arc mantle temperature. Here we use a simple three-dimensional numerical model to quantify the effects of back-arc temperature perturbations on the mantle wedge flow pattern and sub-arc mantle temperature. Our model calculations show that relatively small temperature perturbations in the back-arc result in vigorous inflow of hotter mantle and subdued inflow of colder mantle beneath the arc due to the temperature dependence of the mantle viscosity. This causes a three-dimensional mantle flow pattern that amplifies the along-arc variations in the sub-arc mantle temperature, providing a simple mechanism for volcano clustering.

Numerical Investigation on Sensitivity of Liquid Jet Breakup to Physical Fuel Properties with Experimental Comparison

NASA Astrophysics Data System (ADS)

Kim, Dokyun; Bravo, Luis; Matusik, Katarzyna; Duke, Daniel; Kastengren, Alan; Swantek, Andy; Powell, Christopher; Ham, Frank

2016-11-01

One of the major concerns in modern direct injection engines is the sensitivity of engine performance to fuel characteristics. Recent works have shown that even slight differences in fuel properties can cause significant changes in efficiency and emission of an engine. Since the combustion process is very sensitive to the fuel/air mixture formation resulting from disintegration of liquid jet, the precise assessment of fuel sensitivity on liquid jet atomization process is required first to study the impact of different fuels on the combustion. In the present study, the breaking process of a liquid jet from a diesel injector injecting into a quiescent gas chamber is investigated numerically and experimentally for different liquid fuels (n-dodecane, iso-octane, CAT A2 and C3). The unsplit geometric Volume-of-Fluid method is employed to capture the phase interface in Large-eddy simulations and results are compared against the radiography measurement from Argonne National Lab including jet penetration, liquid mass distribution and volume fraction. The breakup characteristics will be shown for different fuels as well as droplet PDF statistics to demonstrate the influences of the physical properties on the primary atomization of liquid jet. Supported by HPCMP FRONTIER award, US DOD, Office of the Army.

The environmental and medical geochemistry of potentially hazardous materials produced by disasters

USGS Publications Warehouse

Plumlee, Geoffrey S.; Morman, Suzette A.; Meeker, G.P.; Hoefen, Todd M.; Hageman, Philip L.; Wolf, Ruth E.

2014-01-01

Many natural or human-caused disasters release potentially hazardous materials (HM) that may pose threats to the environment and health of exposed humans, wildlife, and livestock. This chapter summarizes the environmentally and toxicologically significant physical, mineralogical, and geochemical characteristics of materials produced by a wide variety of recent disasters, such as volcanic eruptions, hurricanes and extreme storms, spills of mining/mineral-processing wastes or coal extraction by-products, and the 2001 attacks on and collapse of the World Trade Center towers. In describing these characteristics, this chapter also illustrates the important roles that geochemists and other earth scientists can play in environmental disaster response and preparedness. In addition to characterizing in detail the physical, chemical, and microbial makeup of HM generated by the disasters, these roles also include (1) identifying and discriminating potential multiple sources of the materials; (2) monitoring, mapping, and modeling dispersal and evolution of the materials in the environment; (3) understanding how the materials are modified by environmental processes; (4) identifying key characteristics and processes that influence the materials' toxicity to exposed humans and ecosystems; (5) estimating shifts away from predisaster environmental baseline conditions; and (6) using geochemical insights learned from past disasters to help estimate, prepare for, and increase societal resilience to the environmental and related health impacts of future disasters.

Effect of liberibacter infection (huanglongbing disease) of citrus on orange fruit physiology and fruit/fruit juice quality: chemical and physical analyses.

PubMed

Baldwin, Elizabeth; Plotto, Anne; Manthey, John; McCollum, Greg; Bai, Jinhe; Irey, Mike; Cameron, Randall; Luzio, Gary

2010-01-27

More than 90% of oranges in Florida are processed, and since Huanglongbing (HLB) disease has been rumored to affect fruit flavor, chemical and physical analyses were conducted on fruit and juice from healthy (Las -) and diseased (Las +) trees on three juice processing varieties over two seasons, and in some cases several harvests. Fruit, both asymptomatic and symptomatic for the disease, were used, and fresh squeezed and processed/pasteurized juices were evaluated. Fruit and juice characteristics measured included color, size, solids, acids, sugars, aroma volatiles, ascorbic acid, secondary metabolites, pectin, pectin-demethylating enzymes, and juice cloud. Results showed that asymptomatic fruit from symptomatic trees were similar to healthy fruit for many of the quality factors measured, but that juice from asymptomatic and especially symptomatic fruits were often higher in the bitter compounds limonin and nomilin. However, values were generally below reported taste threshold levels, and only symptomatic fruit seemed likely to cause flavor problems. There was variation due to harvest date, which was often greater than that due to disease. It is likely that the detrimental flavor attributes of symptomatic fruit (which often drop off the tree) will be largely diluted in commercial juice blends that include juice from fruit of several varieties, locations, and seasons.

Epistasis in protein evolution

PubMed Central

Starr, Tyler N.

2016-01-01

Abstract The structure, function, and evolution of proteins depend on physical and genetic interactions among amino acids. Recent studies have used new strategies to explore the prevalence, biochemical mechanisms, and evolutionary implications of these interactions—called epistasis—within proteins. Here we describe an emerging picture of pervasive epistasis in which the physical and biological effects of mutations change over the course of evolution in a lineage‐specific fashion. Epistasis can restrict the trajectories available to an evolving protein or open new paths to sequences and functions that would otherwise have been inaccessible. We describe two broad classes of epistatic interactions, which arise from different physical mechanisms and have different effects on evolutionary processes. Specific epistasis—in which one mutation influences the phenotypic effect of few other mutations—is caused by direct and indirect physical interactions between mutations, which nonadditively change the protein's physical properties, such as conformation, stability, or affinity for ligands. In contrast, nonspecific epistasis describes mutations that modify the effect of many others; these typically behave additively with respect to the physical properties of a protein but exhibit epistasis because of a nonlinear relationship between the physical properties and their biological effects, such as function or fitness. Both types of interaction are rampant, but specific epistasis has stronger effects on the rate and outcomes of evolution, because it imposes stricter constraints and modulates evolutionary potential more dramatically; it therefore makes evolution more contingent on low‐probability historical events and leaves stronger marks on the sequences, structures, and functions of protein families. PMID:26833806

Physical activity and mortality: is the association explained by genetic selection?

PubMed

Carlsson, Sofia; Andersson, Tomas; Lichtenstein, Paul; Michaëlsson, Karl; Ahlbom, Anders

2007-08-01

Public health recommendations promote physical activity to improve health and longevity. Recent data suggest that the association between physical activity and mortality may be due to genetic selection. Using data on twins, the authors investigated whether genetic selection explains the association between physical activity and mortality. Data were based on a postal questionnaire answered by 13,109 Swedish twin pairs in 1972. The national Cause of Death Register was used for information about all-cause mortality (n=1,800) and cardiovascular disease mortality (n=638) during 1975-2004. The risk of death was reduced by 34% for men (relative risk=0.64, 95% confidence interval: 0.50, 0.83) and by 25% for women (relative risk=0.75, 95% confidence interval: 0.50, 1.14) reporting high physical activity levels. Within-pair comparisons of monozygotic twins showed that, compared with their less active co-twin, the more active twin had a 20% (odds ratio=0.80, 95% confidence interval: 0.65, 0.99) reduced risk of all-cause mortality and a 32% (odds ratio=0.68, 95% confidence interval: 0.49, 0.95) reduced risk of cardiovascular disease mortality. Results indicate that physical activity is associated with a reduced risk of mortality not due to genetic selection. This finding supports a causal link between physical activity and mortality.

Temporal and vertical variability in optical properties of New England shelf waters during late summer and spring

NASA Astrophysics Data System (ADS)

Sosik, Heidi M.; Green, Rebecca E.; Pegau, W. Scott; Roesler, Collin S.

2001-05-01

Relationships between optical and physical properties were examined on the basis of intensive sampling at a site on the New England continental shelf during late summer 1996 and spring 1997. During both seasons, particles were found to be the primary source of temporal and vertical variability in optical properties since light absorption by dissolved material, though significant in magnitude, was relatively constant. Within the particle pool, changes in phytoplankton were responsible for much of the observed optical variability. Physical processes associated with characteristic seasonal patterns in stratification and mixing contributed to optical variability mostly through effects on phytoplankton. An exception to this generalization occurred during summer as the passage of a hurricane led to a breakdown in stratification and substantial resuspension of nonphytoplankton particulate material. Prior to the hurricane, conditions in summer were highly stratified with subsurface maxima in absorption and scattering coefficients. In spring, stratification was much weaker but increased over the sampling period, and a modest phytoplankton bloom caused surface layer maxima in absorption and scattering coefficients. These seasonal differences in the vertical distribution of inherent optical properties were evident in surface reflectance spectra, which were elevated and shifted toward blue wavelengths in the summer. Some seasonal differences in optical properties, including reflectance spectra, suggest that a significant shift toward a smaller particle size distribution occurred in summer. Shorter timescale optical variability was consistent with a variety of influences including episodic events such as the hurricane, physical processes associated with shelfbreak frontal dynamics, biological processes such as phytoplankton growth, and horizontal patchiness combined with water mass advection.

Effects of leisure-time and occupational physical activity on total mortality risk in NHANES III according to sex, ethnicity, central obesity, and age.

PubMed

Richard, Aline; Martin, Brian; Wanner, Miriam; Eichholzer, Monika; Rohrmann, Sabine

2015-02-01

Associations of physical activity with all-cause mortality seem to be quite strong, but little is known about potential effect modifiers as sex, race/ethnicity, age, and obesity. Data of the Third National Health and Nutrition Examination Survey (NHANES III), conducted 1988-1994 with mortality follow-up until 2006, were used to compare mortality risk between different levels of leisure-time physical activity (LTPA) and occupational physical activity (OPA). Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). LTPA (n = 15,307) was inversely associated with all-cause mortality (HR 0.75, 95% CI 0.64-0.88 for regular vs. no LTPA). There was a statistically significant interaction with age (P = .03), with participants over 60 years of age benefitting more from regular or irregular LTPA. OPA was positively associated with all-cause mortality (HR 1.25, 95% CI 0.85-1.84 for high vs. low OPA), particularly among Mexican-Americans (HR 2.28, 95% CI 1.23-4.22); statistically significant interactions were observed for obesity and gender. LTPA clearly predicts all-cause mortality. However, associations between OPA and all-cause mortality are unclear and need further research with special regard to ethnic differences.

Physical Education and Physical Activity: A Historical Perspective

ERIC Educational Resources Information Center

Guedes, Claudia

2007-01-01

Although many recent studies have shown that the lack of physical activity is one of the major causes of obesity, diabetes, and cardiovascular disease among children and adolescents, few studies have shown the connection between the lack of physical education and the prevalence of a sedentary lifestyle. However, it is clear that physical education…

A laboratory investigation of the effectiveness of various skin and surface decontaminants for aliphatic polyisocyanates.

PubMed

Bello, Dhimiter; Woskie, Susan R; Streicher, Robert P; Stowe, Meredith H; Sparer, Judy; Redlich, Carrie A; Cullen, Mark R; Liu, Youcheng

2005-07-01

Isocyanates may cause contact dermatitis and respiratory sensitization leading to asthma. Dermal exposure to aliphatic isocyanates in auto body shops is very common. However, little is known about the effectiveness of available commercial products used for decontaminating aliphatic polyisocyanates. This experimental study evaluated the decontamination effectiveness of aliphatic polyisocyanates for several skin and surface decontaminants available for use in the auto body industry. The efficiency of two major decontamination mechanisms, namely (i) consumption of free isocyanate groups via chemical reactions with active hydrogen components of the decontaminant and (ii) physical removal processes such as dissolution were studied separately for each decontaminant. Considerable differences were observed among surface decontaminants in their rate of isocyanate consumption, of which those containing free amine groups performed the best. Overall, Pine-Sol(R) MEA containing monoethanolamine was the most efficient surface decontaminant, operating primarily via chemical reaction with the isocyanate group. Polypropylene glycol (PPG) had the highest physical removal efficiency and the lowest reaction rate with isocyanates. All tested skin decontaminants performed similarly, accomplishing decontamination primarily via physical processes and removing 70-80% of isocyanates in one wiping. Limitations of these skin decontaminants are discussed and alternatives presented. In vitro testing using animal skins and in vivo testing with field workers are being conducted to further assess the efficiency and identify related determinants.

Two-dimensional patterns in bacterial veils arise from self-generated, three-dimensional fluid flows.

PubMed

Cogan, N G; Wolgemuth, C W

2011-01-01

The behavior of collections of oceanic bacteria is controlled by metabolic (chemotaxis) and physical (fluid motion) processes. Some sulfur-oxidizing bacteria, such as Thiovulum majus, unite these two processes via a material interface produced by the bacteria and upon which the bacteria are transiently attached. This interface, termed a bacterial veil, is formed by exo-polymeric substances (EPS) produced by the bacteria. By adhering to the veil while continuing to rotate their flagella, the bacteria are able to exert force on the fluid surroundings. This behavior induces a fluid flow that, in turn, causes the bacteria to aggregate leading to the formation of a physical pattern in the veil. These striking patterns are very similar in flavor to the classic convection instability observed when a shallow fluid is heated from below. However, the physics are very different since the flow around the veil is mediated by the bacteria and affects the bacterial densities. In this study, we extend a model of a one-dimensional veil in a two-dimensional fluid to the more realistic two-dimensional veil in a three-dimensional fluid. The linear stability analysis indicates that the Peclet number serves as a bifurcation parameter, which is consistent with experimental observations. We also solve the nonlinear problem numerically and are able to obtain patterns that are similar to those observed in the experiments.

Pyroclast/snow interactions and thermally driven slurry formation. Part 1: Theory for monodisperse grain beds

USGS Publications Warehouse

Walder, J.S.

2000-01-01

Lahars are often produced as pyroclastic flows move over snow. This phenomenon involves a complicated interplay of mechanical and thermal processes that need to be separated to get at the fundamental physics. The thermal physics of pyroclast/snow interactions form the focus of this paper. A theoretical model is developed of heat- and mass transfer at the interface between a layer of uniformly sized pyroclasts and an underlying bed of snow, for the case in which there is no relative shear motion between pyroclasts and snow. A microscale view of the interface is required to properly specify boundary conditions. The physical model leads to the prediction that the upward flux of water vapor - which depends upon emplacement temperature, pyroclast grain size, pyroclast-layer thickness, and snow permeability - is sometimes sufficient to fluidize the pyroclasts. Uniform fluidization is usually unstable to bubble formation, which leads to vigorous convection of the pyroclasts themselves. Thus, predicted threshold conditions for fluidization are tantamount to predicted thresholds for particle convection. Such predictions are quantitatively in good agreement with results of experiments described in part 2 of this paper. Because particle convection commonly causes scour of the snow bed and transformation of the pyroclast layer to a slurry, there exists a 'thermal scour' process for generating lahars from pyroclastic flows moving over snow regardless of the possible role of mechanical scour.

Cardiovascular and other causes of death as a function of lifestyle habits in a quasi extinct middle-aged male population. A 50-year follow-up study.

PubMed

Menotti, Alessandro; Puddu, Paolo Emilio; Maiani, Giuseppe; Catasta, Giovina

2016-05-01

To relate major causes of death with lifestyle habits in an almost extinct male middle-aged population. A 40-59 aged male population of 1712 subjects was examined and followed-up for 50 years. Baseline smoking habits, working physical activity and dietary habits were related to 50 years mortality subdivided into 12 simple and 3 composite causes of death by Cox proportional hazard models. Duration of survival was related to the same characteristics by a multiple linear regression model. Death rate in 50 years was of 97.5%. Out of 12 simple groups of causes of death, 6 were related to smoking habits, 3 to physical activity and 4 to dietary habits. Among composite groups of causes of death, hazard ratios (and their 95% confidence limits) of never smokers versus smokers were 0.68 (0.57-0.81) for major cardiovascular diseases; 0.65 (0.52-0.81) for all cancers; and 0.72 (0.64-0.81) for all-cause deaths. Hazard ratios of vigorous physical activity at work versus sedentary physical activity were 0.63 (0.49-0.80) for major cardiovascular diseases; 1.01 (0.72-1.41) for all cancers; and 0.76 (0.64-0.90) for all-cause deaths. Hazard ratios of Mediterranean Diet versus non-Mediterranean Diet were 0.68 (0.54-0.86) for major cardiovascular diseases; 0.54 (0.40-0.73) for all cancers; and 0.67 (0.57-0.78) for all-cause deaths. Expectancy of life was 12 years longer for men with the 3 best behaviors than for those with the 3 worst behaviors. Some lifestyle habits are strongly related to lifetime mortality. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Physical Activity for the Autistic Child.

ERIC Educational Resources Information Center

Kraft, Robert E.

1983-01-01

Physical, cognitive, and social-emotional symptoms of autism are described, along with possible causes of the condition and treatments. A "theraplay" physical education program in Newark, Delaware, is discussed, where physical activities such as rhythm, body awareness, perceptual motor development, and swimming are used to engage…

25 CFR 224.141 - What must the Secretary do if the tribe responds to the Director's order?

Code of Federal Regulations, 2010 CFR

2010-04-01

... DETERMINATION ACT Periodic Reviews Noncompliance § 224.141 What must the Secretary do if the tribe responds to... Secretary will determine whether the noncompliance caused imminent jeopardy to a physical trust asset. (b) If the Secretary determines that the tribe's noncompliance has caused imminent jeopardy to a physical...

Dynamics of Fluvial Regime and its impact on the population displacement in the Gangetic Plain of West Bengal

NASA Astrophysics Data System (ADS)

Prasad, Suraj; Sen, Anjan

2017-04-01

River bank erosion is one of the major natural hazards in India. Basically it is a natural phenomenon, but the role of anthropogenic factor to trigger the problem is undeniable. In West Bengal, river bank erosion in Ganga River has become an acute problem in Malda and Murshidabad districts. In Musrshidabad district alone, more than 350 Km2 land has been lost in the past four decades and more than 80000 persons have been displaced in the entire state of West Bengal. The trigger for such large scale erosional work has been both natural as well as anthropogenic. Ganga River in West Bengal flows through an underdeveloped river channel, leading to frequent changes in the course of the river that further cause riverbank erosion along the riparian zones of the river. The construction of Farakka Barrage in Malda district in 1975 has only exacerbated the problem, causing siltation and associated erosional processes. The present work deals with the social impacts of the physical process of erosion, and primarily focuses on the migration pattern of uprooted communities of Malda and Murshidabad districts. The study uses Landsat Images and SRTM DEM to assess the changes in the course of Ganga River and primary survey to discern the present and future trends of migration in the affected areas, and concludes with an assessment of the social-ecological-landscape relationships in a region undergoing large scale physical as well as demographic change. Keywords: River Bank Erosion, Ganga River, Farakka Barrage, Landsat, SRTM DEM, Migration

The Evolution of CO in Protoplanetary Disks During Planet Formation

NASA Astrophysics Data System (ADS)

Schwarz, Kamber; Bergin, Edwin

2018-01-01

CO has long been used as a tracer of gas mass. However, recent observations have revealed a low CO to dust mass ratio in numerous protoplanetary disks. In at least some of these systems it is the CO, rather than the total gas mass, which is missing. During my PhD I have used models of protoplanetary disk chemistry as well as millimeter observations to explore the causes and extent of CO depletion in disks. My ALMA observations of CO isotopologues in the TW Hya protoplanetary disk revealed that CO is under-abundant in that system by nearly two orders of magnitude, failing to return to ISM abundances even inside the midplane CO snow line. I have also explored the physical conditions needed to remove carbon from gas phase CO via chemically process using a large grid of chemical models. My analysis reveals that in the warm molecular layer, a wide range of physical conditions can result in an order of magnitude reduction of CO in the outer disk. In the inner disk, ionization, such as from cosmic rays, is needed for chemical reprocessing to occur. However, it is very difficult for chemical processes alone to result in two orders of magnitude of depletion, such as is seen in TW Hya and inferred for other disks. In the midplane, where planets form, it is even more difficult to remove carbon from CO without invoking cosmic rays. My work shows that while CO is missing from the gas in protoplanetary disks, chemistry is unlikely to be the sole cause.

Observation and Modeling of Clear Air Turbulence (CAT) over Europe

NASA Astrophysics Data System (ADS)

Sprenger, M.; Mayoraz, L.; Stauch, V.; Sharman, B.; Polymeris, J.

2012-04-01

CAT represents a very relevant phenomenon for aviation safety. It can lead to passenger injuries, causes an increase in fuel consumption and, under severe intensity, can involve structural damages to the aircraft. The physical processes causing CAT remain at present not fully understood. Moreover, because of its small scale, CAT cannot be represented in numerical weather prediction (NWP) models. In this study, the physical processes related to CAT and its representation in NWP models is further investigated. First, 134 CAT events over Europe are extracted from a flight monitoring data base (FDM), run by the SWISS airline and containing over 100'000 flights. The location, time, and meteorological parameters along the turbulent spots are analysed. Furthermore, the 7-km NWP model run by the Swiss National Weather Service (Meteoswiss) is used to calculate model-based CAT indices, e.g. Richardson number, Ellrod & Knapp turbulence index and a complex/combined CAT index developed at NCAR. The CAT indices simulated with COSMO-7 is then compared to the observed CAT spots, hence allowing to assess the model's performance, and potential use in a CAT warning system. In a second step, the meteorological conditions associated with CAT are investigated. To this aim, CAT events are defined as coherent structures in space and in time, i.e. their dimension and life cycle is studied, in connection with jet streams and upper-level fronts. Finally, in a third step the predictability of CAT is assessed, by comparing CAT index predictions based on different lead times of the NWP model COSMO-7

Effect of MeV Electron Radiation on Europa’s Surface Ice Analogs

NASA Astrophysics Data System (ADS)

Gudipati, Murthy; Henderson, Bryana; Bateman, Fred

2017-10-01

MeV electrons that impact Europa’s trailing hemisphere and cause both physical and chemical alteration of the surface and near-surface. The trailing hemisphere receives far lower fluxes above 25 MeV as compared with lower energy particles, but can cause significant chemical and physical modifications at these energies. With NASA's planned Europa Clipper mission and a Europa Lander Concept on the horizon, it is critical to understand and quantify the effect of Europa’s radiation environment on the surface and near surface.Electrons penetrate through ice by far the deepest at any given energy compared to protons and ions, making the role of electrons very important to understand. In addition, secondary radiation - Bremsstrahlung, in X-ray wavelengths - is generated during high-energy particle penetration through solids. Secondary X-rays are equally lethal to life and penetrate even deeper than electrons, making the cumulative effect of radiation on damaging organic matter on the near surface of Europa a complex process that could have effects several meters below Europa’s surface. Other physical properties such as coloration could be caused by radiation.In order to quantify this effect under realistic Europa trailing hemisphere conditions, we devised, built, tested, and obtained preliminary results using our ICE-HEART instrument prototype totally funded by JPL’s internal competition funding for Research and Technology Development. Our Ice Chamber for Europa High-Energy Electron And Radiation-Environment Testing (ICE-HEART) operates at ~100 K. We have also implemented a magnet that is used to remove primary electrons subsequent to passing through an ice column, in order to determine the flux of secondary X-radiation and its penetration through ice.Some of the first results from these studies will be presented and their relevance to understand physical and chemical properties of Europa’s trailing hemisphere surface.This work has been carried out at Jet Propulsion Laboratory, California Institute of Technology under a contract with the National Aeronautics and Space Administration, and funded by JPL’s R&TD Program and NASA Solar System Workings Program.

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.

Investigation of the radiation background in the interaction region of the medium-energy electron relativisitic heavy ion collider (MeRHIC)

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

Beebe-Wang,J.

There are three main sources of the radiation background in MeRHIC: forward synchrotron radiation generated upstream of the detector, the direct backward radiation caused by the photons hitting beampipe downstream of the detector, and the indirect secondary radiation caused by hard photons hitting vacuum systems, masks, collimators, absorbers or any other elements in the interaction region. In this paper, we first calculate the primary radiation distribution by employing electromagnetic theory. Then we obtain the direct backward scattering rate by applying the kinematic Born approximation deduced from scattering dynamics. The diffuse scattering cross section is calculated as a function of themore » surface properties of the MeRHIC vacuum system. Finally, the dominating physical processes and minimization of indirect secondary radiation is presented and discussed.« less

Alcohol and the Physically Impaired: Special Focus.

ERIC Educational Resources Information Center

Boros, Alexander, Ed.

1989-01-01

The articles in this special issue explore the connections between the dual disabilities of alcohol abuse and physical impairment, and reflect progress made in exploring the causes and treatments of alcohol abuse among the physically impaired. Selected articles include: "Results of a Model Intervention Program for Physically Impaired…

Caution Flags in Physical Education.

ERIC Educational Resources Information Center

Claxton, David; And Others

1994-01-01

Lists several common physical fitness exercises that may cause more harm than good (both physically and emotionally). Physical educators must be aware of the dangers of certain exercises and activities. The article examines problems with inappropriate warmups, peer team selection, exercise as punishment, elimination games, and standing in line.…

Sources of avoidance motivation: Valence effects from physical effort and mental rotation.

PubMed

Morsella, Ezequiel; Feinberg, Giles H; Cigarchi, Sepeedeh; Newton, James W; Williams, Lawrence E

2011-09-01

When reaching goals, organisms must simultaneously meet the overarching goal of conserving energy. According to the law of least effort, organisms will select the means associated with the least effort. The mechanisms underlying this bias remain unknown. One hypothesis is that organisms come to avoid situations associated with unnecessary effort by generating a negative valence toward the stimuli associated with such situations. Accordingly, merely using a dysfunctional, 'slow' computer mouse causes participants to dislike ambient neutral images (Study 1). In Study 2, nonsense shapes were liked less when associated with effortful processing (135° of mental rotation) versus easier processing (45° of rotation). Complementing 'fluency' effects found in perceptuo-semantic research, valence emerged from action-related processing in a principled fashion. The findings imply that negative valence associations may underlie avoidance motivations, and have practical implications for educational/workplace contexts in which effort and positive affect are conducive to success.

Plant-Pathogen Effectors: Cellular Probes Interfering with Plant Defenses in Spatial and Temporal Manners

PubMed Central

Toruño, Tania Y.; Stergiopoulos, Ioannis; Coaker, Gitta

2017-01-01

Plants possess large arsenals of immune receptors capable of recognizing all pathogen classes. To cause disease, pathogenic organisms must be able to overcome physical barriers, suppress or evade immune perception, and derive nutrients from host tissues. Consequently, to facilitate some of these processes, pathogens secrete effector proteins that promote colonization. This review covers recent advances in the field of effector biology, focusing on conserved cellular processes targeted by effectors from diverse pathogens. The ability of effectors to facilitate pathogen entry into the host interior, suppress plant immune perception, and alter host physiology for pathogen benefit is discussed. Pathogens also deploy effectors in a spatial and temporal manner, depending on infection stage. Recent advances have also enhanced our understanding of effectors acting in specific plant organs and tissues. Effectors are excellent cellular probes that facilitate insight into biological processes as well as key points of vulnerability in plant immune signaling networks. PMID:27359369

Synthetic schlieren—application to the visualization and characterization of air convection

NASA Astrophysics Data System (ADS)

Taberlet, Nicolas; Plihon, Nicolas; Auzémery, Lucile; Sautel, Jérémy; Panel, Grégoire; Gibaud, Thomas

2018-05-01

Synthetic schlieren is a digital image processing optical method relying on the variation of optical index to visualize the flow of a transparent fluid. In this article, we present a step-by-step, easy-to-implement and affordable experimental realization of this technique. The method is applied to air convection caused by a warm surface. We show that the velocity of rising convection plumes can be linked to the temperature of the warm surface and propose a simple physical argument to explain this dependence. Moreover, using this method, one can reveal the tenuous convection plumes rising from one’s hand, a phenomenon invisible to the naked eye. This spectacular result may help students to realize the power of careful data acquisition combined with astute image processing techniques. This spectacular result may help students to realize the power of careful data acquisition combined with astute image processing techniques (refer to the video abstract).

Innovative biological approaches for monitoring and improving water quality

PubMed Central

Aracic, Sanja; Manna, Sam; Petrovski, Steve; Wiltshire, Jennifer L.; Mann, Gülay; Franks, Ashley E.

2015-01-01

Water quality is largely influenced by the abundance and diversity of indigenous microbes present within an aquatic environment. Physical, chemical and biological contaminants from anthropogenic activities can accumulate in aquatic systems causing detrimental ecological consequences. Approaches exploiting microbial processes are now being utilized for the detection, and removal or reduction of contaminants. Contaminants can be identified and quantified in situ using microbial whole-cell biosensors, negating the need for water samples to be tested off-site. Similarly, the innate biodegradative processes can be enhanced through manipulation of the composition and/or function of the indigenous microbial communities present within the contaminated environments. Biological contaminants, such as detrimental/pathogenic bacteria, can be specifically targeted and reduced in number using bacteriophages. This mini-review discusses the potential application of whole-cell microbial biosensors for the detection of contaminants, the exploitation of microbial biodegradative processes for environmental restoration and the manipulation of microbial communities using phages. PMID:26322034

Leisure-time aerobic physical activity, muscle-strengthening activity and mortality risks among US adults: the NHANES linked mortality study.

PubMed

Zhao, Guixiang; Li, Chaoyang; Ford, Earl S; Fulton, Janet E; Carlson, Susan A; Okoro, Catherine A; Wen, Xiao Jun; Balluz, Lina S

2014-02-01

Regular physical activity elicits multiple health benefits in the prevention and management of chronic diseases. We examined the mortality risks associated with levels of leisure-time aerobic physical activity and muscle-strengthening activity based on the 2008 Physical Activity Guidelines for Americans among US adults. We analysed data from the 1999 to 2004 National Health and Nutrition Examination Survey with linked mortality data obtained through 2006. Cox proportional HRs with 95% CIs were estimated to assess risks for all-causes and cardiovascular disease (CVD) mortality associated with aerobic physical activity and muscle-strengthening activity. Of 10 535 participants, 665 died (233 deaths from CVD) during an average of 4.8-year follow-up. Compared with participants who were physically inactive, the adjusted HR for all-cause mortality was 0.64 (95% CI 0.52 to 0.79) among those who were physically active (engaging in ≥150 min/week of the equivalent moderate-intensity physical activity) and 0.72 (95% CI 0.54 to 0.97) among those who were insufficiently active (engaging in >0 to <150 min/week of the equivalent moderate-intensity physical activity). The adjusted HR for CVD mortality was 0.57 (95% CI 0.34 to 0.97) among participants who were insufficiently active and 0.69 (95% CI 0.43 to 1.12) among those who were physically active. Among adults who were insufficiently active, the adjusted HR for all-cause mortality was 44% lower by engaging in muscle-strengthening activity ≥2 times/week. Engaging in aerobic physical activity ranging from insufficient activity to meeting the 2008 Guidelines reduces the risk of premature mortality among US adults. Engaging in muscle-strengthening activity ≥2 times/week may provide additional benefits among insufficiently active adults.

Density structure of submarine slump and normal sediments of the first gas production test site at Daini-Atsumi Knoll near Nankai Trough, estimated by LWD logging data

NASA Astrophysics Data System (ADS)

Suzuki, K.; Takayama, T.; Fujii, T.; Yamamoto, K.

2014-12-01

Many geologists have discussed slope instability caused by gas-hydrate dissociation, which could make movable fluid in pore space of sediments. However, physical property changes caused by gas hydrate dissociation would not be so simple. Moreover, during the period of natural gas-production from gas-hydrate reservoir applying depressurization method would be completely different phenomena from dissociation processes in nature, because it could not be caused excess pore pressure, even though gas and water exist. Hence, in all cases, physical properties of gas-hydrate bearing sediments and that of their cover sediments are quite important to consider this phenomena, and to carry out simulation to solve focusing phenomena during gas hydrate dissociation periods. Daini-Atsumi knoll that was the first offshore gas-production test site from gas-hydrate is partially covered by slumps. Fortunately, one of them was penetrated by both Logging-While-Drilling (LWD) hole and pressure-coring hole. As a result of LWD data analyses and core analyses, we have understood density structure of sediments from seafloor to Bottom Simulating Reflector (BSR). The results are mentioned as following. ・Semi-confined slump showed high-density, relatively. It would be explained by over-consolidation that was result of layer-parallel compression caused by slumping. ・Bottom sequence of slump has relative high-density zones. It would be explained by shear-induced compaction along slide plane. ・Density below slump tends to increase in depth. It is reasonable that sediments below slump deposit have been compacting as normal consolidation. ・Several kinds of log-data for estimating physical properties of gas-hydrate reservoir sediments have been obtained. It will be useful for geological model construction from seafloor until BSR. We can use these results to consider geological model not only for slope instability at slumping, but also for slope stability during depressurized period of gas production from gas-hydrate. AcknowledgementThis study was supported by funding from the Research Consortium for Methane Hydrate Resources in Japan (MH21 Research Consortium) planned by the Ministry of Economy, Trade and Industry (METI).

The future of nearshore processes research

USGS Publications Warehouse

Elko, Nicole A.; Feddersen, Falk; Foster, Diane; Hapke, Cheryl J.; McNinch, Jesse E.; Mulligan, Ryan P.; Tuba Ӧzkan-Haller, H.; Plant, Nathaniel G.; Raubenheimer, Britt

2014-01-01

The nearshore is the transition region between land and the continental shelf including (from onshore to offshore) coastal plains, wetlands, estuaries, coastal cliffs, dunes, beaches, surf zones (regions of wave breaking), and the inner shelf (Figure ES-1). Nearshore regions are vital to the national economy, security, commerce, and recreation. The nearshore is dynamically evolving, is often densely populated, and is under increasing threat from sea level rise, long-term erosion, extreme storms, and anthropogenic influences. Worldwide, almost one billion people live at elevations within 10 m of present sea level. Long-term erosion threatens communities, infrastructure, ecosystems, and habitat. Extreme storms can cause billions of dollars of damage. Degraded water quality impacts ecosystem and human health. Nearshore processes, the complex interactions between water, sediment, biota, and humans, must be understood and predicted to manage this often highly developed yet vulnerable nearshore environment. Over the past three decades, the understanding of nearshore processes has improved. However, societal needs are growing with increased coastal urbanization and threats of future climate change, and significant scientific challenges remain. To address these challenges, members of academia, industry, and federal agencies (USGS, USACE, NPS, NOAA, FEMA, ONR) met at the “The Past and Future of Nearshore Processes Research: Reflections on the Sallenger Years and a New Vision for the Future” workshop to develop a nearshore processes research vision where societal needs and science challenges intersect. The resulting vision is comprised of three broad research themes: Long-term coastal evolution due to natural and anthropogenic processes: As global climate change alters the rates of sea level rise and potentially storm patterns and coastal urbanization increases over the coming decades, an understanding of coastal evolution is critical. Improved knowledge of long-term morphological, ecological, and societal processes and their interactions will result in an improved ability to simulate coastal change. This will enable proactive solutions for resilient coasts and better guidance for reducing coastal vulnerability.Extreme Events: Flooding, erosion, and the subsequent recovery: Hurricane Sandy caused flooding and erosion along hundreds of miles of shoreline, flooded New York City, and impacted communities and infrastructure. Overall U.S. coastal extreme event related economic losses have increased substantially. Furthermore, climate change may cause an increase in coastal extreme events and rising sea levels could increase the occurrence of extreme events. Addressing this research theme will result in an improved understanding of the physical processes during extreme events, leading to improved models of flooding, erosion, and recovery. The resulting societal benefit will be more resilient coastal communities.The physical, biological and chemical processes impacting human and ecosystem health: Nearshore regions are used for recreation, tourism, and human habitation, and provide habitat and valuable ecosystem services. These areas must be sustained for future generations, however overall coastal water quality is declining due to microbial pathogens, fertilizers, pesticides, and heavy metal contamination, threatening ecosystem and human health. To ensure sustainable nearshore regions, predictive real-time water- and sediment-based based pollutant modeling capabilities must be developed, which requires expanding our knowledge of the physics, chemistry, and biology of the nearshore. The resulting societal benefits will include better beach safety, healthier ecosystems, and improved mitigation and regulatory policies.The scientists and engineers of the U.S. nearshore community are poised to make significant progress on these research themes, which have significant societal impact. The U.S. nearshore community, including academic, government, and industry colleagues, recommends multi-agency investment into a coordinated development of observational and modeling research infrastructure to address these themes, as discussed in the whitepaper. The observational infrastructure should include development of new sensors and methods, focused observational programs, and expanded nearshore observing systems. The modeling infrastructure should include improved process representation, better model coupling, incorporation of data assimilation techniques, and testing of real-time models. The observations will provide test beds to compare and improve models.

Turbulence and Fluid Flow: Perspectives. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

ERIC Educational Resources Information Center

Simpson, James R.

This module is part of a series on Physical Processes in Terrestrial and Aquatic Ecosystems. The materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process.…

Autogenic Deposits as A Potential Recorder of High-Frequency Signals: The Role of Autogenic Processes Revisited

NASA Astrophysics Data System (ADS)

Li, H.; Plink-Bjorklund, P.

2017-12-01

Studies (e.g., Jerolmack and Paola, 2010) have suggested that autogenic processes act as a filter for high-frequency environmental signals, and the underlying assumption is that autogenic processes can cause fluctuations in sediment and water discharge that modify or shred the signal. This assumption, however, fails to recognize that autogenic processes and their final products are dynamic and that they can respond to allogenic forcings. We compile a database containing published field studies, physical experiments, and numerical modeling works, and analyze the data under different boundary conditions. Our analyses suggest different conclusions. Autogenic processes are intrinsic to the sedimentary system, and they possess distinct patterns under steady boundary conditions. Upon changing boundary conditions, the autogenic patterns are also likely to change (depending on the magnitude of the change in the boundary conditions). Therefore, the pattern change provides us with the opportunity to restore the high-frequency signals that may not pass through the transfer zone. Here we present the theoretical basis for using autogenic deposits to infer high-frequency signals as well as modern and ancient field examples, physical experiments, and modeling works to illustrate the autogenic response to allogenic forcings. The field studies show the potential of using autogenic deposits to restore short-term climatic variability. The experiments demonstrate that autogenic processes in rivers are closely linked to sediment and water discharge. The modeling examples reveal the counteracting effects of some autogenic processes to form a self-organized pattern under a set of specific boundary conditions. We also highlight the limitations and challenges that need more research efforts to restore high-frequency signals. Some critical issues include the magnitude of the signals, the effect of the interference between different signals, and the incompleteness of the autogenic deposits.

Salt dissolution and sinkhole formation: Results of laboratory experiments

NASA Astrophysics Data System (ADS)

Oz, Imri; Eyal, Shalev; Yoseph, Yechieli; Ittai, Gavrieli; Elad, Levanon; Haim, Gvirtzman

2016-10-01

The accepted mechanism for the formation of thousands of sinkholes along the coast of the Dead Sea suggests that their primary cause is dissolution of a salt layer by groundwater undersaturated with respect to halite. This is related to the drop in the Dead Sea level, which caused a corresponding drop of the freshwater-saltwater interface, resulting in fresher groundwater replacing the brines that were in contact with the salt layer. In this study we used physical laboratory experiments to examine the validity of this mechanism by reproducing the full dynamic natural process and to examine the impact of different hydrogeological characteristics on this process. The experimental results show surface subsidence and sinkhole formation. The stratigraphic configurations of the aquifer, together with the mechanical properties of the salt layer, determine the dynamic patterns of the sinkhole formation (instantaneous versus gradual formation). Laboratory experiments were also used to study the potential impact of future stratification in the Dead Sea, if and when the "Red Sea-Dead Sea Canal" project is carried out, and the Dead Sea level remains stable. The results show that the dissolution rates are slower by 1 order of magnitude in comparison with a nonstratified saltwater body, and therefore, the processes of salt dissolution and sinkhole formation will be relatively restrained under these conditions.

Freeze Technology for Nuclear Applications - 13590

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

Rostmark, Susanne C.; Knutsson, Sven; Lindberg, Maria

2013-07-01

Freezing of soil materials is a complicated process of a number of physical processes: - freezing of pore water in a thermal gradient, - cryogenic suction causing water migration and - ice formation expanding pores inducing frost heave. Structural changes due to increase of effective stress during freezing also take place. The over consolidation gives a powerful dewatering/drying effect and the freeze process causes separation of contaminates. Artificial ground freezing (AGF is a well established technique first practiced in south Wales, as early as 1862. AGF is mostly used to stabilize tunnels and excavations. During the last ten years underwatermore » applications of freeze technologies based on the AGF have been explored in Sweden. The technology can, and has been, used in many different steps in a remediation action. Freeze Sampling where undisturbed samples are removed in both soft and hard sediment/sludge, Freeze Dredging; retrieval of sediment with good precision and minimal redistribution, and Freeze Drying; volume reduction of contaminated sludge/sediment. The application of these technologies in a nuclear or radioactive environment provides several advantages. Sampling by freezing gives for example an advantage of an undisturbed sample taken at a specified depth, salvaging objects by freezing or removal of sludges is other applications of this, for the nuclear industry, novel technology. (authors)« less

Adaptive self-organization of Bali's ancient rice terraces.

PubMed

Lansing, J Stephen; Thurner, Stefan; Chung, Ning Ning; Coudurier-Curveur, Aurélie; Karakaş, Çağil; Fesenmyer, Kurt A; Chew, Lock Yue

2017-06-20

Spatial patterning often occurs in ecosystems as a result of a self-organizing process caused by feedback between organisms and the physical environment. Here, we show that the spatial patterns observable in centuries-old Balinese rice terraces are also created by feedback between farmers' decisions and the ecology of the paddies, which triggers a transition from local to global-scale control of water shortages and rice pests. We propose an evolutionary game, based on local farmers' decisions that predicts specific power laws in spatial patterning that are also seen in a multispectral image analysis of Balinese rice terraces. The model shows how feedbacks between human decisions and ecosystem processes can evolve toward an optimal state in which total harvests are maximized and the system approaches Pareto optimality. It helps explain how multiscale cooperation from the community to the watershed scale could persist for centuries, and why the disruption of this self-organizing system by the Green Revolution caused chaos in irrigation and devastating losses from pests. The model shows that adaptation in a coupled human-natural system can trigger self-organized criticality (SOC). In previous exogenously driven SOC models, adaptation plays no role, and no optimization occurs. In contrast, adaptive SOC is a self-organizing process where local adaptations drive the system toward local and global optima.

Laboratory investigation of surface processes on airless bodies due to electrostatic dust mobilization

NASA Astrophysics Data System (ADS)

Wang, X.; Hood, N.; Schwan, J.; Hsu, H. W.; Horanyi, M.

2017-12-01

Electrostatic dust mobilization on the surfaces of airless bodies due to direct exposure to solar wind and solar ultraviolet (UV) radiation has been suggested from a number of unusual planetary observations and supported by our recent laboratory experiments. This electrostatic process may have a significant contribution in the evolution of these surfaces in addition to other surface processes, e.g., thermal fragmentation. The critical questions are how this process changes the surface physical characteristics and how efficient this process can be. We report new laboratory experiments that record dust activities as function of the incoming fluxes of photons or energetic electrons over a long exposure time under Earth gravity. Dust is observed to hop and move on the surface, causing the significant change in surface morphology and becoming smoother over time. Our results indicate that the dynamics of dust mobilization may be complicated by temporal charging effect as dust moves. Various sizes and types of dust are examined, showing large effects on dust mobilization. These laboratory data will help us to predict the electrostatic surface processes and estimate their timescales in space conditions.

Multilevel modeling of damage accumulation processes in metals

NASA Astrophysics Data System (ADS)

Kurmoiartseva, K. A.; Trusov, P. V.; Kotelnikova, N. V.

2017-12-01

To predict the behavior of components and constructions it is necessary to develop the methods and mathematical models which take into account the self-organization of microstructural processes and the strain localization. The damage accumulation processes and the evolution of material properties during deformation are important to take into account. The heterogeneity of the process of damage accumulation is due to the appropriate physical mechanisms at the scale levels, which are lower than the macro-level. The purpose of this work is to develop a mathematical model for analyzing the behavior of polycrystalline materials that allows describing the damage accumulation processes. Fracture is the multistage and multiscale process of the build-up of micro- and mesodefects over the wide range of loading rates. The formation of microcracks by mechanisms is caused by the interactions of the dislocations of different slip systems, barriers, boundaries and the inclusions of the secondary phase. This paper provides the description of some of the most well-known models of crack nucleation and also suggests the structure of a mathematical model based on crystal plasticity and dislocation models of crack nucleation.

Carbon dioxide warming of the early Earth

NASA Technical Reports Server (NTRS)

Arrhenius, G.

1997-01-01

Svante Arrhenius' research in atmospheric physics extended beyond the recent past and the near future states of the Earth, which today are at the center of sociopolitical attention. His plan encompassed all of the physical phenomena known at the time to relate to the formation and evolution of stars and planets. His two-volume textbook on cosmic physics is a comprehensive synopsis of the field. The inquiry into the possible cause of the ice ages and the theory of selective wavelength filter control led Arrhenius to consider the surface states of the other terrestrial planets, and of the ancient Earth before it had been modified by the emergence of life. The rapid escape of hydrogen and the equilibration with igneous rocks required that carbon in the early atmosphere prevailed mainly in oxidized form as carbon dioxide, together with other photoactive gases exerting a greenhouse effect orders of magnitude larger than in our present atmosphere. This effect, together with the ensuing chemical processes, would have set the conditions for life to evolve on our planet, seeded from spores spreading through an infinite Universe, and propelled, as Arrhenius thought, by stellar radiation pressure.

Physical gills prevent drowning of many wetland insects, spiders and plants.

PubMed

Pedersen, Ole; Colmer, Timothy D

2012-03-01

Insects, spiders and plants risk drowning in their wetland habitats. The slow diffusion of O(2) can cause asphyxiation when underwater, as O(2) supply cannot meet respiratory demands. Some animals and plants have found a common solution to the major challenge: how to breathe underwater with respiratory systems evolved for use in air? Hydrophobic surfaces on their bodies possess gas films that act as a 'physical gill' to collect O(2) when underwater and thus sustain respiration. In aquatic insects, this feature/process has been termed 'plastron respiration'. Here, we demonstrate the similarities in function between underwater respiration of insect (Aphelocheirus aestivalis) plastrons and gas films on leaves of wetland plants (Phalaris arundinacea) and also show the importance of these physical gills by the resulting changes upon their removal. The gas films provide an enlarged gas-water interface to enhance O(2) uptake underwater that is above that if only spiracles (insects) or stomata (plants) provided the gas-phase contact with the water. Body-surface gas films contribute to the survival of many insects, spiders and plants in aquatic and flood-prone environments.

Intermediate-mass Elements in Young Supernova Remnants Reveal Neutron Star Kicks by Asymmetric Explosions

NASA Astrophysics Data System (ADS)

Katsuda, Satoru; Morii, Mikio; Janka, Hans-Thomas; Wongwathanarat, Annop; Nakamura, Ko; Kotake, Kei; Mori, Koji; Müller, Ewald; Takiwaki, Tomoya; Tanaka, Masaomi; Tominaga, Nozomu; Tsunemi, Hiroshi

2018-03-01

The birth properties of neutron stars (NSs) yield important information about the still-debated physical processes that trigger the explosion as well as on intrinsic neutron-star physics. These properties include the high space velocities of young neutron stars with average values of several 100 km s‑1, with an underlying “kick” mechanism that is not fully clarified. There are two competing possibilities that could accelerate NSs during their birth: anisotropic ejection of either stellar debris or neutrinos. Here we present new evidence from X-ray measurements that chemical elements between silicon and calcium in six young gaseous supernova remnants are preferentially expelled opposite to the direction of neutron star motion. There is no correlation between the kick velocities and magnetic field strengths of these neutron stars. Our results support a hydrodynamic origin of neutron-star kicks connected to asymmetric explosive mass ejection, and they conflict with neutron-star acceleration scenarios that invoke anisotropic neutrino emission caused by particle and nuclear physics in combination with very strong neutron-star magnetic fields.

Carbon dioxide warming of the early Earth.

PubMed

Arrhenius, G

1997-02-01

Svante Arrhenius' research in atmospheric physics extended beyond the recent past and the near future states of the Earth, which today are at the center of sociopolitical attention. His plan encompassed all of the physical phenomena known at the time to relate to the formation and evolution of stars and planets. His two-volume textbook on cosmic physics is a comprehensive synopsis of the field. The inquiry into the possible cause of the ice ages and the theory of selective wavelength filter control led Arrhenius to consider the surface states of the other terrestrial planets, and of the ancient Earth before it had been modified by the emergence of life. The rapid escape of hydrogen and the equilibration with igneous rocks required that carbon in the early atmosphere prevailed mainly in oxidized form as carbon dioxide, together with other photoactive gases exerting a greenhouse effect orders of magnitude larger than in our present atmosphere. This effect, together with the ensuing chemical processes, would have set the conditions for life to evolve on our planet, seeded from spores spreading through an infinite Universe, and propelled, as Arrhenius thought, by stellar radiation pressure.

Eye-tracking and EMG supported 3D Virtual Reality - an integrated tool for perceptual and motor development of children with severe physical disabilities: a research concept.

PubMed

Pulay, Márk Ágoston

2015-01-01

Letting children with severe physical disabilities (like Tetraparesis spastica) to get relevant motional experiences of appropriate quality and quantity is now the greatest challenge for us in the field of neurorehabilitation. These motional experiences may establish many cognitive processes, but may also cause additional secondary cognitive dysfunctions such as disorders in body image, figure invariance, visual perception, auditory differentiation, concentration, analytic and synthetic ways of thinking, visual memory etc. Virtual Reality is a technology that provides a sense of presence in a real environment with the help of 3D pictures and animations formed in a computer environment and enable the person to interact with the objects in that environment. One of our biggest challenges is to find a well suited input device (hardware) to let the children with severe physical disabilities to interact with the computer. Based on our own experiences and a thorough literature review we have come to the conclusion that an effective combination of eye-tracking and EMG devices should work well.

Preschool physics: Using the invisible property of weight in causal reasoning tasks

PubMed Central

Williamson, Rebecca A.; Meltzoff, Andrew N.

2018-01-01

Causal reasoning is an important aspect of scientific thinking. Even young human children can use causal reasoning to explain observations, make predictions, and design actions to bring about specific outcomes in the physical world. Weight is an interesting type of cause because it is an invisible property. Here, we tested preschool children with causal problem-solving tasks that assessed their understanding of weight. In an experimental setting, 2- to 5-year-old children completed three different tasks in which they had to use weight to produce physical effects—an object displacement task, a balance-scale task, and a tower-building task. The results showed that the children’s understanding of how to use object weight to produce specific object-to-object causal outcomes improved as a function of age, with 4- and 5-year-olds showing above-chance performance on all three tasks. The younger children’s performance was more variable. The pattern of results provides theoretical insights into which aspects of weight processing are particularly difficult for preschool children and why they find it difficult. PMID:29561840

Integration of active pharmaceutical ingredient solid form selection and particle engineering into drug product design.

PubMed

Ticehurst, Martyn David; Marziano, Ivan

2015-06-01

This review seeks to offer a broad perspective that encompasses an understanding of the drug product attributes affected by active pharmaceutical ingredient (API) physical properties, their link to solid form selection and the role of particle engineering. While the crucial role of active pharmaceutical ingredient (API) solid form selection is universally acknowledged in the pharmaceutical industry, the value of increasing effort to understanding the link between solid form, API physical properties and drug product formulation and manufacture is now also being recognised. A truly holistic strategy for drug product development should focus on connecting solid form selection, particle engineering and formulation design to both exploit opportunities to access simpler manufacturing operations and prevent failures. Modelling and predictive tools that assist in establishing these links early in product development are discussed. In addition, the potential for differences between the ingoing API physical properties and those in the final product caused by drug product processing is considered. The focus of this review is on oral solid dosage forms and dry powder inhaler products for lung delivery. © 2015 Royal Pharmaceutical Society.

Preschool physics: Using the invisible property of weight in causal reasoning tasks.

PubMed

Wang, Zhidan; Williamson, Rebecca A; Meltzoff, Andrew N

2018-01-01

Causal reasoning is an important aspect of scientific thinking. Even young human children can use causal reasoning to explain observations, make predictions, and design actions to bring about specific outcomes in the physical world. Weight is an interesting type of cause because it is an invisible property. Here, we tested preschool children with causal problem-solving tasks that assessed their understanding of weight. In an experimental setting, 2- to 5-year-old children completed three different tasks in which they had to use weight to produce physical effects-an object displacement task, a balance-scale task, and a tower-building task. The results showed that the children's understanding of how to use object weight to produce specific object-to-object causal outcomes improved as a function of age, with 4- and 5-year-olds showing above-chance performance on all three tasks. The younger children's performance was more variable. The pattern of results provides theoretical insights into which aspects of weight processing are particularly difficult for preschool children and why they find it difficult.

Overweight, Obesity and Strong Attitudes: Predicting Participation in Physical Activity in a Predominantly Hispanic College Population

ERIC Educational Resources Information Center

Magoc, Dejan; Tomaka, Joe; Thompson, Sharon

2010-01-01

Background: Obesity is the leading cause of preventable death and conveys risk for diabetes, hypertension, heart disease and stroke. Overweight and obesity are common among college students, with surveys showing 35 per cent of college students to be overweight. Unhealthy diets and low physical activity are the major causes. Objective: To examine…

Perceived Barriers and Facilitators to Participation in Physical Activity during the School Lunch Break for Girls Aged 12-13 Years

ERIC Educational Resources Information Center

Watson, Amanda; Eliott, Jaklin; Mehta, Kaye

2015-01-01

Given the short-and long-term health implications associated with overweight and obesity plus the likelihood of overweight or obesity to continue into adulthood, addressing the causes of overweight and obesity in childhood is a significant public health concern. One underlying cause of overweight and obesity is insufficient physical activity. The…

Children's conceptions of mental illness: a naïve theory approach.

PubMed

Fox, Claudine; Buchanan-Barrow, Eithne; Barrett, Martyn

2010-09-01

This paper reports two studies that investigated children's conceptions of mental illness using a naïve theory approach, drawing upon a conceptual framework for analysing illness representations which distinguishes between the identity, causes, consequences, curability, and timeline of an illness. The studies utilized semi-structured interviewing and card selection tasks to assess 6- to 11-year-old children's conceptions of the causes and consequences (Study 1) and the curability and timeline (Study 2) of different mental and physical illnesses/ailments. The studies revealed that, at all ages, the children held coherent causal-explanatory ideas about the causes, consequences, curability, and timeline of both mental and physical illnesses/ailments. However, while younger children tended to rely on their knowledge of common physical illnesses when thinking about mental illnesses, providing contagion and contamination explanations of cause, older children demonstrated differences in their thinking about mental and physical illnesses. No substantial gender differences were found in the children's thinking. It is argued that children hold coherent conceptions of mental illness at all ages, but that mental illness only emerges as an ontologically distinct conceptual domain by the end of middle childhood.

Self-efficacy mediates the relationship between behavioral processes of change and physical activity in older breast cancer survivors.

PubMed

Loprinzi, Paul D; Cardinal, Bradley J

2013-01-01

The degree to which breast cancer survivors use behavioral processes of change has not been investigated. Additionally, the relationship between behavioral processes and other theory-based mediators of adult physical activity behavior has not been extensively studied among breast cancer survivors. The objectives of this study were to: (1) determine the extent to which breast cancer survivors use behavioral processes associated with physical activity behavior change, and (2) examine the inter-relationships between behavioral processes, self-efficacy, and physical activity behavior among breast cancer survivors. Sixty-nine breast cancer survivors completed surveys examining behavioral processes and exercise-specific self-efficacy. Six months later they completed a self-report physical activity questionnaire. Findings showed the majority of breast cancer survivors did not use approximately half of the behavioral processes on a regular basis, and self-efficacy completely mediated the relationship between behavioral processes and physical activity. Health care professionals may help enhance self-efficacy and ultimately increase physical activity behavior in breast cancer survivors by teaching behavior skills such as enlisting social support.

Fast Adjustments of the Asian Summer Monsoon to Anthropogenic Aerosols

NASA Astrophysics Data System (ADS)

Li, Xiaoqiong; Ting, Mingfang; Lee, Dong Eun

2018-01-01

Anthropogenic aerosols are a major factor contributing to human-induced climate change, particularly over the densely populated Asian monsoon region. Understanding the physical processes controlling the aerosol-induced changes in monsoon rainfall is essential for reducing the uncertainties in the future projections of the hydrological cycle. Here we use multiple coupled and atmospheric general circulation models to explore the physical mechanisms for the aerosol-driven monsoon changes on different time scales. We show that anthropogenic aerosols induce an overall reduction in monsoon rainfall and circulation, which can be largely explained by the fast adjustments over land north of 20∘N. This fast response occurs before changes in sea surface temperature (SST), largely driven by aerosol-cloud interactions. However, aerosol-induced SST feedbacks (slow response) cause substantial changes in the monsoon meridional circulation over the oceanic regions. Both the land-ocean asymmetry and meridional temperature gradient are key factors in determining the overall monsoon circulation response.

Fetal alcohol spectrum disorders: an overview.

PubMed

Riley, Edward P; Infante, M Alejandra; Warren, Kenneth R

2011-06-01

When fetal alcohol syndrome (FAS) was initially described, diagnosis was based upon physical parameters including facial anomalies and growth retardation, with evidence of developmental delay or mental deficiency. Forty years of research has shown that FAS lies towards the extreme end of what are now termed fetal alcohol spectrum disorders (FASD). The most profound effects of prenatal alcohol exposure are on the developing brain and the cognitive and behavioral effects that ensue. Alcohol exposure affects brain development via numerous pathways at all stages from neurogenesis to myelination. For example, the same processes that give rise to the facial characteristics of FAS also cause abnormal brain development. Behaviors as diverse as executive functioning to motor control are affected. This special issue of Neuropsychology Review addresses these changes in brain and behavior highlighting the relationship between the two. A diagnostic goal is to recognize FAS as a disorder of brain rather than one of physical characteristics.

Mitigation of biofouling using electromagnetic fields in tubular heat exchangers-condensers cooled by seawater.

PubMed

Trueba, Alfredo; García, Sergio; Otero, Félix M

2014-01-01

Electromagnetic field (EMF) treatment is presented as an alternative physical treatment for the mitigation of biofouling adhered to the tubes of a heat exchanger-condenser cooled by seawater. During an experimental phase, a fouling biofilm was allowed to grow until experimental variables indicated that its growth had stabilised. Subsequently, EMF treatment was applied to seawater to eliminate the biofilm and to maintain the achieved cleanliness. The results showed that EMFs precipitated ions dissolved in the seawater. As a consequence of the application of EMFs, erosion altered the intermolecular bonding of extracellular polymers, causing the destruction of the biofilm matrix and its detachment from the inner surface of the heat exchanger-condenser tubes. This detachment led to the partial removal of a mature biofilm and a partial recovery of the efficiency lost in the heat transfer process by using a physical treatment that is harmless to the marine environment.

Energy dissipation in flows through curved spaces.

PubMed

Debus, J-D; Mendoza, M; Succi, S; Herrmann, H J

2017-02-14

Fluid dynamics in intrinsically curved geometries is encountered in many physical systems in nature, ranging from microscopic bio-membranes all the way up to general relativity at cosmological scales. Despite the diversity of applications, all of these systems share a common feature: the free motion of particles is affected by inertial forces originating from the curvature of the embedding space. Here we reveal a fundamental process underlying fluid dynamics in curved spaces: the free motion of fluids, in the complete absence of solid walls or obstacles, exhibits loss of energy due exclusively to the intrinsic curvature of space. We find that local sources of curvature generate viscous stresses as a result of the inertial forces. The curvature- induced viscous forces are shown to cause hitherto unnoticed and yet appreciable energy dissipation, which might play a significant role for a variety of physical systems involving fluid dynamics in curved spaces.

Plastometric tests for plasticine as physical modelling material

NASA Astrophysics Data System (ADS)

Wójcik, Łukasz; Lis, Konrad; Pater, Zbigniew

2016-12-01

This paper presents results of plastometric tests for plasticine, used as material for physical modelling of metal forming processes. The test was conducted by means of compressing by flat dies of cylindrical billets at various temperatures. The aim of the conducted research was comparison of yield stresses and course of material flow curves. Tests were made for plasticine in black and white colour. On the basis of the obtained experimental results, the influence of forming parameters change on flow curves course was determined. Sensitivity of yield stresses change in function of material deformation, caused by forging temperature change within the scope of 0&C ÷ 20&C and differentiation of strain rate for ˙ɛ = 0.563; ˙ɛ = 0.0563; ˙ɛ = 0.0056s-1,was evaluated. Experimental curves obtained in compression test were described by constitutive equations. On the basis of the obtained results the function which most favourably describes flow curves was chosen.

Cleaner production in a remanufacturing process of air compressors.

PubMed

Esquer, Javier; Arvayo, Jose Angel; Alvarez-Chavez, Clara Rosalia; Munguia-Vega, Nora Elba; Velazquez, Luis

2017-03-01

This article provides relevant results of a cleaner production program conducted in a company dedicated to remanufacturing air compressors in the city of Hermosillo, Sonora, Mexico. The overall study design was based on an integration of acknowledged cleaner production and pollution prevention programs. Although this kind of program also involves environmental issues, this study focused on occupational health and safety by addressing different aspects of the work environment: ergonomic, physical (noise and lighting), and chemical. Particularly, ergonomic aspects were evaluated through the Modular Arrangement of Predetermined Time Standards (MODAPTS) method. For physical aspects, noise and lighting were addressed through Standard No. NOM-011-STPS-2001 and Standard No. NOM-025-STPS-2008 respectively. In addition, chemical aspects were analyzed through material safety data sheets and different search tools. Root causes of each risk were identified, and options to prevent, eliminate, and/or reduce each risk have been provided.

Computation models simulating notochordal cell extinction during early ageing of an intervertebral disc.

PubMed

Louman-Gardiner, K M; Coombe, D; Hunter, C J

2011-12-01

Lower back pain due to intervertebral disc (IVD) degeneration is a prevalent problem which drastically affects the quality of life of millions of sufferers. Healthy IVDs begin with high populations of notochordal cells in the nucleus pulposus, while by the second stage of degeneration, these cells will be replaced by chondrocyte-like cells. Because the IVD is avascular, these cells rely on passive diffusion of nutrients to survive. It is thought that this transition in cell phenotype causes the shift of the IVD's physical properties, which impede the flow of nutrients. Our computational model of the IVD illustrates its ability to simulate the evolving chemical and mechanical environments occurring during the early ageing process. We demonstrate that, due to the insufficient nutrient supply and accompanying changes in physical properties of the IVD, there was a resultant exponential decay in the number of notochordal cells over time.

Lokomat training in vascular dementia: motor improvement and beyond!

PubMed

Calabrò, Rocco Salvatore; De Luca, Rosaria; Leo, Antonino; Balletta, Tina; Marra, Angela; Bramanti, Placido

2015-12-01

Vascular dementia (VaD) is a general term describing problems with reasoning, planning, judgment, memory, and other thought processes caused by brain damage from impaired blood flow to the brain. Cognitive rehabilitation and physical therapy are the mainstays of dementia treatment, although often ineffective because of the scarce collaboration of the patients. However, emerging data suggest that physical activity may reduce the risk of cognitive impairment, mainly VaD, in older people living independently. Herein, we describe a 72-year-old male affected by VaD, in which traditional cognitive training in addition to intensive gait robotic rehabilitation (by using Lokomat device) led to a significant improvement in the motor and cognitive function. This promising finding may be related either to the intensive and repetitive aerobic exercises or to the task-oriented training with computerized visual feedback, which can be considered as a relevant tool to increase patients' motor output, involvement, and motivation during robotic training.

Evolution of high-mass star-forming regions .

NASA Astrophysics Data System (ADS)

Giannetti, A.; Leurini, S.; Wyrowski, F.; Urquhart, J.; König, C.; Csengeri, T.; Güsten, R.; Menten, K. M.

Observational identification of a coherent evolutionary sequence for high-mass star-forming regions is still missing. We use the progressive heating of the gas caused by the feedback of high-mass young stellar objects to prove the statistical validity of the most common schemes used to observationally define an evolutionary sequence for high-mass clumps, and identify which physical process dominates in the different phases. From the spectroscopic follow-ups carried out towards the TOP100 sample between 84 and 365 km s^-1 giga hertz, we selected several multiplets of CH3CN, CH3CCH, and CH3OH lines to derive the physical properties of the gas in the clumps along the evolutionary sequence. We demonstrate that the evolutionary sequence is statistically valid, and we define intervals in L/M separating the compression, collapse and accretion, and disruption phases. The first hot cores and ZAMS stars appear at L/M≈10usk {L_ȯ}msun-1

(Bayesian) Inference for X-ray Timing

NASA Astrophysics Data System (ADS)

Huppenkothen, Daniela

2016-07-01

Fourier techniques have been incredibly successful in describing variability of X-ray binaries (XRBs) and Active Galactic Nuclei (AGN). The detection and characterization of both broadband noise components and quasi-periodic oscillations as well as their behavior in the context of spectral changes during XRB outbursts has become an important tool for studying the physical processes of accretion and ejection in these systems. In this talk, I will review state-of-the-art techniques for characterizing variability in compact objects and show how these methods help us understand the causes of the observed variability and how we may use it to probe fundamental physics. Despite numerous successes, however, it has also become clear that many scientific questions cannot be answered with traditional timing methods alone. I will therefore also present recent advances, some in the time domain like CARMA, to modeling variability with generative models and discuss where these methods might lead us in the future.

The effects of baryon physics, black holes and active galactic nucleus feedback on the mass distribution in clusters of galaxies

NASA Astrophysics Data System (ADS)

Martizzi, Davide; Teyssier, Romain; Moore, Ben; Wentz, Tina

2012-06-01

The spatial distribution of matter in clusters of galaxies is mainly determined by the dominant dark matter component; however, physical processes involving baryonic matter are able to modify it significantly. We analyse a set of 500 pc resolution cosmological simulations of a cluster of galaxies with mass comparable to Virgo, performed with the AMR code RAMSES. We compare the mass density profiles of the dark, stellar and gaseous matter components of the cluster that result from different assumptions for the subgrid baryonic physics and galaxy formation processes. First, the prediction of a gravity-only N-body simulation is compared to that of a hydrodynamical simulation with standard galaxy formation recipes, and then all results are compared to a hydrodynamical simulation which includes thermal active galactic nucleus (AGN) feedback from supermassive black holes (SMBHs). We find the usual effects of overcooling and adiabatic contraction in the run with standard galaxy formation physics, but very different results are found when implementing SMBHs and AGN feedback. Star formation is strongly quenched, producing lower stellar densities throughout the cluster, and much less cold gas is available for star formation at low redshifts. At redshift z= 0 we find a flat density core of radius 10 kpc in both the dark and stellar matter density profiles. We speculate on the possible formation mechanisms able to produce such cores and we conclude that they can be produced through the coupling of different processes: (I) dynamical friction from the decay of black hole orbits during galaxy mergers; (II) AGN-driven gas outflows producing fluctuations of the gravitational potential causing the removal of collisionless matter from the central region of the cluster; (III) adiabatic expansion in response to the slow expulsion of gas from the central region of the cluster during the quiescent mode of AGN activity.

Levels of Information Processing in a Fitts law task (LIPFitts)

NASA Technical Reports Server (NTRS)

Mosier, K. L.; Hart, S. G.

1986-01-01

State-of-the-art flight technology has restructured the task of human operators, decreasing the need for physical and sensory resources, and increasing the quantity of cognitive effort required, changing it qualitatively. Recent technological advances have the most potential for impacting a pilot in two areas: performance and mental workload. In an environment in which timing is critical, additional cognitive processing can cause performance decrements, and increase a pilot's perception of the mental workload involved. The effects of stimulus processing demands on motor response performance and subjective mental workload are examined, using different combinations of response selection and target acquisition tasks. The information processing demands of the response selection were varied (e.g., Sternberg memory set tasks, math equations, pattern matching), as was the difficulty of the response execution. Response latency as well as subjective workload ratings varied in accordance with the cognitive complexity of the task. Movement times varied according to the difficulty of the response execution task. Implications in terms of real-world flight situations are discussed.

Conditions for energy generation as an alternative approach to compost utilization.

PubMed

Raclavska, H; Juchelkova, D; Skrobankova, H; Wiltowski, T; Campen, A

2011-01-01

Very strict limits constrain the current possibilities for compost utilization in agriculture and for land reclamation, thus creating a need for other compost utilization practices. A favourable alternative can be compost utilization as a renewable heat source - alternative fuel. The changes of the basic physical-chemical parameters during the composting process are evaluated. During the composting process, energy losses of 920 kJ/kg occur, caused by carbohydrate decomposition (loss of 12.64% TOC). The net calorific value for mature compost was 11.169 kJ/kg dry matter. The grain size of compost below 0.045 mm has the highest ash content. The energetic utilization of compost depended on moisture, which can be influenced by paper addition or by prolonging the time of maturation to six months.

Enhancing Students’ Interest through Mathematics Learning

NASA Astrophysics Data System (ADS)

Azmidar, A.; Darhim, D.; Dahlan, J. A.

2017-09-01

A number of previous researchers indicated that students’ mathematics interest still low because most of them have perceived that mathematics is very difficult, boring, not very practical, and have many abstract theorems that were very hard to understand. Another cause is the teaching and learning process used, which is mechanistic without considering students’ needs. Learning is more known as the process of transferring the knowledge to the students. Let students construct their own knowledge with the physical and mental reflection that is done by activity in the new knowledge. This article is literature study. The purpose of this article is to examine the Concrete-Pictorial-Abstract approach in theoretically to improve students’ mathematics interest. The conclusion of this literature study is the Concrete-Pictorial-Abstract approach can be used as an alternative to improve students’ mathematics interest.

Heterogeneity in the clinical presentation of Eagle's syndrome.

PubMed

Mendelsohn, Abie H; Berke, Gerald S; Chhetri, Dinesh K

2006-03-01

Eagle's syndrome (ES) or symptomatic elongated styloid process is an uncommon but important cause of chronic head and neck pain. This study reports our experience in the diagnosis and treatment of a series of patients with ES. Patient histories, radiographic tests, and operative reports of 3 patients over a 3-month period were prospectively collected. Tertiary referral otolaryngology service. All patients had resolution of symptoms relating to their elongated styloid processes after surgical resection. Although sometimes clouded by coexisting symptoms, ES can be easily diagnosed based on good history taking and physical examination. If diagnosed appropriately, surgical treatment can be administered promptly. Patients with ES commonly have a long history of chronic pain treated by multiple physicians. Appropriate diagnosis can lead to prompt treatment of this condition. C-4.

Approaches to eliminating chlorofluorocarbon use in manufacturing.

PubMed Central

Boyhan, W S

1992-01-01

Until quite recently, chlorofluorocarbons (CFCs) had been considered the safest and most benign of industrial chemicals. Their physical and chemical properties made them an integral part of manufacturing processes for electronics products. The recognition that CFCs destroy the stratospheric ozone layer, with consequent enormous consequences to all forms of life on earth, has led to international agreements which will end virtually all possibly before. This impending phaseout of CFCs has caused electronics manufacturers to examine alternative chemicals and processing methods. This manuscript documents the steps AT&T has taken to reach its goal of 100% phaseout of CFCs by years-end 1994. These actions include top-down management support with combined bottom-up thrusts, an internal information gathering and dissemination center, internal technology transfer, and external corporate activism. Images PMID:11607258

Influence of cirrus clouds on weather and climate processes A global perspective

NASA Technical Reports Server (NTRS)

Liou, K.-N.

1986-01-01

Current understanding and knowledge of the composition and structure of cirrus clouds are reviewed and documented in this paper. In addition, the radiative properties of cirrus clouds as they relate to weather and climate processes are described in detail. To place the relevance and importance of cirrus composition, structure and radiative properties into a global perspective, pertinent results derived from simulation experiments utilizing models with varying degrees of complexity are presented; these have been carried out for the investigation of the influence of cirrus clouds on the thermodynamics and dynamics of the atmosphere. In light of these reviews, suggestions are outlined for cirrus-radiation research activities aimed toward the development and improvement of weather and climate models for a physical understanding of cause and effect relationships and for prediction purposes.

Observations and Modeling of Turbulent Air-Sea Coupling in Coastal and Strongly Forced Condition

NASA Astrophysics Data System (ADS)

Ortiz-Suslow, David G.

The turbulent fluxes of momentum, mass, and energy across the ocean-atmosphere boundary are fundamental to our understanding of a myriad of geophysical processes, such as wind-wave generation, oceanic circulation, and air-sea gas transfer. In order to better understand these fluxes, empirical relationships were developed to quantify the interfacial exchange rates in terms of easily observed parameters (e.g., wind speed). However, mounting evidence suggests that these empirical formulae are only valid over the relatively narrow parametric space, i.e. open ocean conditions in light to moderate winds. Several near-surface processes have been observed to cause significant variance in the air-sea fluxes not predicted by the conventional functions, such as a heterogeneous surfaces, swell waves, and wave breaking. Further study is needed to fully characterize how these types of processes can modulate the interfacial exchange; in order to achieve this, a broad investigation into air-sea coupling was undertaken. The primary focus of this work was to use a combination of field and laboratory observations and numerical modeling, in regimes where conventional theories would be expected to breakdown, namely: the nearshore and in very high winds. These seemingly disparate environments represent the marine atmospheric boundary layer at its physical limit. In the nearshore, the convergence of land, air, and sea in a depth-limited domain marks the transition from a marine to a terrestrial boundary layer. Under extreme winds, the physical nature of the boundary layer remains unknown as an intermediate substrate layer, sea spray, develops between the atmosphere and ocean surface. At these ends of the MABL physical spectrum, direct measurements of the near-surface processes were made and directly related to local sources of variance. Our results suggest that the conventional treatment of air-sea fluxes in terms of empirical relationships developed from a relatively narrow set of environmental conditions do not generalize to the coastal and extreme wind environments. This body of work represents a multi-faceted approach to understanding physical air-sea interactions in varied regimes and using a wide array of investigatory methods.

Physically demanding jobs and occupational injury and disability in the U.S. Army.

PubMed

Hollander, Ilyssa E; Bell, Nicole S

2010-10-01

Effective job assignments should take into account physical capabilities to perform required tasks. Failure to do so is likely to result in increased injuries and musculoskeletal disability. To evaluate the association between job demands and health outcomes among U.S. Army soldiers. Multivariate Cox proportional hazards analysis is used to describe associations between job demands, hospitalizations, and disability among 261,096 enlisted Army soldiers in heavily, moderately, and lightly physically demanding occupations (2000-2005) who were followed for up to 5 years. Controlling for gender, race, and age, soldiers in heavily demanding jobs were at increased risk for any-cause injury, on-duty injuries, any-cause hospitalizations, and any-cause disability, but not for musculoskeletal disability. Army job assignments should more accurately match physical capabilities to job demands and/or jobs should be redesigned to reduce injuries. Though musculoskeletal disorders are often the result of acute injury, the demographic and occupational risk patterns differ from acute injury.

Brettanomyces bruxellensis yeasts: impact on wine and winemaking.

PubMed

Agnolucci, Monica; Tirelli, Antonio; Cocolin, Luca; Toffanin, Annita

2017-09-21

Yeasts belonging to the Brettanomyces/Dekkera genus are non-conventional yeasts, which affect winemaking by causing wine spoilage all over the world. This mini-review focuses on recent results concerning the presence of Brettanomyces bruxellensis throughout the wine processing chain. Here, culture-dependent and independent methods to detect this yeast on grapes and at the very early stage of wine production are encompassed. Chemical, physical and biological tools, devised for the prevention and control of such a detrimental species during winemaking are also presented. Finally, the mini-review identifies future research areas relevant to the improvement of wine safety and sensory profiles.

Automatic multiple-sample applicator and electrophoresis apparatus

NASA Technical Reports Server (NTRS)

Grunbaum, B. W. (Inventor)

1977-01-01

An apparatus for performing electrophoresis and a multiple-sample applicator is described. Electrophoresis is a physical process in which electrically charged molecules and colloidal particles, upon the application of a dc current, migrate along a gel or a membrane that is wetted with an electrolyte. A multiple-sample applicator is provided which coacts with a novel tank cover to permit an operator either to depress a single button, thus causing multiple samples to be deposited on the gel or on the membrane simultaneously, or to depress one or more sample applicators separately by means of a separate button for each applicator.

Fluid Physics

NASA Image and Video Library

2003-05-10

These images, from David Weitz’s liquid crystal research, show ordered uniform sized droplets (upper left) before they are dried from their solution. After the droplets are dried (upper right), they are viewed with crossed polarizers that show the deformation caused by drying, a process that orients the bipolar structure of the liquid crystal within the droplets. When an electric field is applied to the dried droplets (lower left), and then increased (lower right), the liquid crystal within the droplets switches its alignment, thereby reducing the amount of light that can be scattered by the droplets when a beam is shone through them.

Limb-darkening and the structure of the Jovian atmosphere

NASA Technical Reports Server (NTRS)

Newman, W. I.; Sagan, C.

1978-01-01

By observing the transit of various cloud features across the Jovian disk, limb-darkening curves were constructed for three regions in the 4.6 to 5.1 mu cm band. Several models currently employed in describing the radiative or dynamical properties of planetary atmospheres are here examined to understand their implications for limb-darkening. The statistical problem of fitting these models to the observed data is reviewed and methods for applying multiple regression analysis are discussed. Analysis of variance techniques are introduced to test the viability of a given physical process as a cause of the observed limb-darkening.

On the Violence of High Explosive Reactions

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

Tarver, C M; Chidester, S K

High explosive reactions can be caused by three general energy deposition processes: impact ignition by frictional and/or shear heating; bulk thermal heating; and shock compression. The violence of the subsequent reaction varies from benign slow combustion to catastrophic detonation of the entire charge. The degree of violence depends on many variables, including the rate of energy delivery, the physical and chemical properties of the explosive, and the strength of the confinement surrounding the explosive charge. The current state of experimental and computer modeling research on the violence of impact, thermal, and shock-induced reactions is reviewed.

Dimensional crossover in fragmentation

NASA Astrophysics Data System (ADS)

Sotolongo-Costa, Oscar; Rodriguez, Arezky H.; Rodgers, G. J.

2000-11-01

Experiments in which thick clay plates and glass rods are fractured have revealed different behavior of fragment mass distribution function in the small and large fragment regions. In this paper we explain this behavior using non-extensive Tsallis statistics and show how the crossover between the two regions is caused by the change in the fragments’ dimensionality during the fracture process. We obtain a physical criterion for the position of this crossover and an expression for the change in the power-law exponent between the small and large fragment regions. These predictions are in good agreement with the experiments on thick clay plates.

Physical Activity and Your Heart

MedlinePlus

... causes your heart rate to go up Walking, hiking, jogging, running Water aerobics or swimming laps Bicycling, skateboarding, rollerblading, and jumping rope Ballroom dancing and aerobic dancing Tennis, soccer, hockey, and basketball Benefits of Physical Activity Physical activity has many health ...

Learning from physics text: A synthesis of recent research

NASA Astrophysics Data System (ADS)

Alexander, Patricia A.; Kulikowich, Jonna M.

Learning from physics text is described as a complex interaction of learner, text, and context variables. As a multidimensional procedure, text processing in the domain of physics relies on readers' knowledge and interest, and on readers' ability to monitor or regulate their processing. Certain textual features intended to assist readers in understanding and remembering physics content may actually work to the detriment of those very processes. Inclusion of seductive details and the incorporation of analogies may misdirect readers' attention or may increase processing demands, particularly in those cases when readers' physics knowledge is low. The questioning behaviors of teachers also impact on the task of comprehending physics texts. Finally, within the context of the classroom, the information that teachers dispense or the materials they employ can significantly influence the process of learning from physics text.

Schizophrenia and Physical Comorbidity.

PubMed

Šimunović Filipčić, Ivona; Filipčić, Igor

2018-06-01

Schizophrenia is a severe psychiatric disorder increasingly recognized as a systemic disorder. In addition to the burden and suffering caused by the mental illness itself, individuals with schizophrenia have a high risk for physical illnesses. The life expectancy gap remains 13 to 30 years wider in people with schizophrenia compared to the general population. This premature mortality is caused largely by deaths due to cardiovascular disease, cancer, diabetes mellitus, and other natural causes, poor diagnosis and treatment, and insufficient prevention of modifiable risk factors. Although the links between schizophrenia and physical illnesses are well established, in clinical practice, physical illnesses in patients with schizophrenia are often overlooked, and the mortality gap between general population and people with schizophrenia continues to widen. The physical health of people with schizophrenia is commonly self-neglected but also ignored by people around them and by health systems, resulting in significant physical health disparities and limited access to health services. The root of the problem of insufficient healthcare appear to lie in interrelated contributory factors from illness, patients, and medical and mental healthcare system. Furthermore, a growing body of literature has been indicating the effect of the chronic physical illness on the treatment outcome of psychosis. Premature mortality and disability could be reduced if there was a greater focus on the implementation of strategies that effectively prevent modifiable risk factors from the first psychotic episode and enhance early recognition of physical illnesses, reduce the burden of physical comorbidity and lead to improved health outcomes. Ultimately, to improve treatment outcome and to reduce the suffering of people with schizophrenia, it is crucial to treat physical comorbidity promptly and assertively from the appearance of the first symptoms of the psychotic disorder. The integrative approach and collaborative care within all levels of healthcare providers should be the imperative in clinical practice.

Climate change and physical disturbance cause similar community shifts in biological soil crusts

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

Ferrenberg, Scott; Reed, Sasha C.; Belnap, Jayne

In biological soil crusts (biocrusts)—communities of mosses, lichens, cyanobacteria, and heterotrophs living at the soil surface— fundamental components of drylands worldwide, and destruction of biocrusts dramatically alters biogeochemical processes, hydrology, surface energy balance, and vegetation cover are present.Though there has been long-standing concern over impacts of physical disturbances on biocrusts (e.g., trampling by livestock, damage from vehicles), there is increasing concern over the potential for climate change to alter biocrust community structure. Using long-term data from the Colorado Plateau, in this paper we examined the effects of 10 y of experimental warming and altered precipitation (in full-factorial design) on biocrustmore » communities and compared the effects of altered climate with those of long-term physical disturbance (>10 y of replicated human trampling). Surprisingly, altered climate and physical disturbance treatments had similar effects on biocrust community structure. Warming, altered precipitation frequency [an increase of small (1.2 mm) summer rainfall events], and physical disturbance from trampling all promoted early successional community states marked by dramatic declines in moss cover and increases in cyanobacteria cover, with more variable effects on lichens. Although the pace of community change varied significantly among treatments, these results suggest that multiple aspects of climate change will affect biocrusts to the same degree as physical disturbance. Finally, this is particularly disconcerting in the context of warming, as temperatures for drylands are projected to increase beyond those imposed as treatments in our study.« less

Climate change and physical disturbance cause similar community shifts in biological soil crusts

DOE PAGES

Ferrenberg, Scott; Reed, Sasha C.; Belnap, Jayne

2015-09-14

In biological soil crusts (biocrusts)—communities of mosses, lichens, cyanobacteria, and heterotrophs living at the soil surface— fundamental components of drylands worldwide, and destruction of biocrusts dramatically alters biogeochemical processes, hydrology, surface energy balance, and vegetation cover are present.Though there has been long-standing concern over impacts of physical disturbances on biocrusts (e.g., trampling by livestock, damage from vehicles), there is increasing concern over the potential for climate change to alter biocrust community structure. Using long-term data from the Colorado Plateau, in this paper we examined the effects of 10 y of experimental warming and altered precipitation (in full-factorial design) on biocrustmore » communities and compared the effects of altered climate with those of long-term physical disturbance (>10 y of replicated human trampling). Surprisingly, altered climate and physical disturbance treatments had similar effects on biocrust community structure. Warming, altered precipitation frequency [an increase of small (1.2 mm) summer rainfall events], and physical disturbance from trampling all promoted early successional community states marked by dramatic declines in moss cover and increases in cyanobacteria cover, with more variable effects on lichens. Although the pace of community change varied significantly among treatments, these results suggest that multiple aspects of climate change will affect biocrusts to the same degree as physical disturbance. Finally, this is particularly disconcerting in the context of warming, as temperatures for drylands are projected to increase beyond those imposed as treatments in our study.« less

THE HOW AND WHY OF THE MOVEMENT SYSTEM AS THE IDENTITY OF PHYSICAL THERAPY

PubMed Central

2017-01-01

The Movement System was adopted as the identity of physical therapy as one of the 8 guiding principles accompanying the Vision Statement of 2013. At its inception physical therapy was considered more of a technical field rather than that of a professional field. Physicians were to diagnose the patient's problem and the therapist was to follow the prescription provided by the physician with the primary purpose being to relieve symptoms such as pain or muscle weakness. Even by the 1960's, the prescription became more of a referral and there was recognition that therapists were making decisions about the patient's treatment and discharge disposition. The role of the physical therapist in pathokinesiologic problems has been well accepted over the years but as insights are gained about the role of movement in musculoskeletal pain, the concept of kinesiopathologic problems is being defined. Whether the movement dysfunction is from a pathokinesiologic or a kinesiopathologic mechanisms, the underlying physiologic process is movement which is the composite action of the movement system. This article provides a brief discussion of the steps leading to promotion of the identity and the reasons that further defining and promoting the movement system as the body system for which physical therapists are responsible is necessary for the full recognition of the profession. As suggested by the kinesiopathologic concept of movement inducing pathology, physical therapists can address the cause of musculoskeletal problems and not just symptoms or consequences such as the pathoanatomic problem. Level of Evidence: 5 PMID:29158948

Influence of physical exercise on traumatic brain injury deficits: scaffolding effect.

PubMed

Archer, Trevor

2012-05-01

Traumatic brain injury (TBI) may be due to a bump, blow, or jolt to the head or a penetrating head injury that disrupts normal brain function; it presents an ever-growing, serious public health problem that causes a considerable number of fatalities and cases of permanent disability annually. Physical exercise restores the healthy homeostatic regulation of stress, affect and the regulation of hypothalamic-pituitary-adrenal axis. Physical activity attenuates or reverses the performance deficits observed in neurocognitive tasks. It induces anti-apoptotic effects and buttresses blood-brain barrier intactness. Exercise offers a unique non-pharmacologic, non-invasive intervention that incorporates different regimes, whether dynamic or static, endurance, or resistance. Exercise intervention protects against vascular risk factors that include hypertension, diabetes, cellular inflammation, and aortic rigidity. It induces direct changes in cerebrovasculature that produce beneficial changes in cerebral blood flow, angiogenesis and vascular disease improvement. The improvements induced by physical exercise regimes in brain plasticity and neurocognitive performance are evident both in healthy individuals and in those afflicted by TBI. The overlap and inter-relations between TBI effects on brain and cognition as related to physical exercise and cognition may provide lasting therapeutic benefits for recovery from TBI. It seems likely that some modification of the notion of scaffolding would postulate that physical exercise reinforces the adaptive processes of the brain that has undergone TBI thereby facilitating the development of existing networks, albeit possibly less efficient, that compensate for those lost through damage. © Springer Science+Business Media, LLC 2011

Climate change and physical disturbance cause similar community shifts in biological soil crusts

USGS Publications Warehouse

Ferrenberg, Scott; Reed, Sasha C.; Belnap, Jayne

2015-01-01

Biological soil crusts (biocrusts)—communities of mosses, lichens, cyanobacteria, and heterotrophs living at the soil surface—are fundamental components of drylands worldwide, and destruction of biocrusts dramatically alters biogeochemical processes, hydrology, surface energy balance, and vegetation cover. While there has been long-standing concern over impacts of 5 physical disturbances on biocrusts (e.g., trampling by livestock, damage from vehicles), there is also increasing concern over the potential for climate change to alter biocrust community structure. Using long-term data from the Colorado Plateau, USA, we examined the effects of 10 years of experimental warming and altered precipitation (in full-factorial design) on biocrust communities, and compared the effects of altered climate with those of long-term physical 10 disturbance (>10 years of replicated human trampling). Surprisingly, altered climate and physical disturbance treatments had similar effects on biocrust community structure. Warming, altered precipitation frequency [an increase of small (1.2 mm) summer rainfall events], and physical disturbance from trampling all promoted early successional community states marked by dramatic declines in moss cover and increased cyanobacteria cover, with more variable effects 15 on lichens. While the pace of community change varied significantly among treatments, our results suggest that multiple aspects of climate change will affect biocrusts to the same degree as physical disturbance. This is particularly disconcerting in the context of warming, as temperatures for drylands are projected to increase beyond those imposed by the climate treatments used in our study.

THE HOW AND WHY OF THE MOVEMENT SYSTEM AS THE IDENTITY OF PHYSICAL THERAPY.

PubMed

Sahrmann, Shirley

2017-11-01

The Movement System was adopted as the identity of physical therapy as one of the 8 guiding principles accompanying the Vision Statement of 2013. At its inception physical therapy was considered more of a technical field rather than that of a professional field. Physicians were to diagnose the patient's problem and the therapist was to follow the prescription provided by the physician with the primary purpose being to relieve symptoms such as pain or muscle weakness. Even by the 1960's, the prescription became more of a referral and there was recognition that therapists were making decisions about the patient's treatment and discharge disposition. The role of the physical therapist in pathokinesiologic problems has been well accepted over the years but as insights are gained about the role of movement in musculoskeletal pain, the concept of kinesiopathologic problems is being defined. Whether the movement dysfunction is from a pathokinesiologic or a kinesiopathologic mechanisms, the underlying physiologic process is movement which is the composite action of the movement system. This article provides a brief discussion of the steps leading to promotion of the identity and the reasons that further defining and promoting the movement system as the body system for which physical therapists are responsible is necessary for the full recognition of the profession. As suggested by the kinesiopathologic concept of movement inducing pathology, physical therapists can address the cause of musculoskeletal problems and not just symptoms or consequences such as the pathoanatomic problem. 5.

A new approach to identify the sensitivity and importance of physical parameters combination within numerical models using the Lund-Potsdam-Jena (LPJ) model as an example

NASA Astrophysics Data System (ADS)

Sun, Guodong; Mu, Mu

2017-05-01

An important source of uncertainty, which causes further uncertainty in numerical simulations, is that residing in the parameters describing physical processes in numerical models. Therefore, finding a subset among numerous physical parameters in numerical models in the atmospheric and oceanic sciences, which are relatively more sensitive and important parameters, and reducing the errors in the physical parameters in this subset would be a far more efficient way to reduce the uncertainties involved in simulations. In this context, we present a new approach based on the conditional nonlinear optimal perturbation related to parameter (CNOP-P) method. The approach provides a framework to ascertain the subset of those relatively more sensitive and important parameters among the physical parameters. The Lund-Potsdam-Jena (LPJ) dynamical global vegetation model was utilized to test the validity of the new approach in China. The results imply that nonlinear interactions among parameters play a key role in the identification of sensitive parameters in arid and semi-arid regions of China compared to those in northern, northeastern, and southern China. The uncertainties in the numerical simulations were reduced considerably by reducing the errors of the subset of relatively more sensitive and important parameters. The results demonstrate that our approach not only offers a new route to identify relatively more sensitive and important physical parameters but also that it is viable to then apply "target observations" to reduce the uncertainties in model parameters.

Characterization and nultivariate analysis of physical properties of processing peaches

USDA-ARS?s Scientific Manuscript database

Characterization of physical properties of fruits represents the first vital step to ensure optimal performance of fruit processing operations and is also a prerequisite in the development of new processing equipment. In this study, physical properties of engineering significance to processing of th...

[The mechanism of phenoptosis: 2. Hayflick limit is caused by the programmed attenuation of bioenergetics].

PubMed

Trubitsin, A G

2010-01-01

This article continues earlier started theme on a substantiation of the programmed aging mechanism (phenoptosis). The concept underlying this mechanism is that the life represents a lot of the interconnected physical and chemical processes moving by the bioenergetics. The gradual programmed decrease of the level of bioenergetics causes the slow and coordinated attenuation of all physiological functions, i.e. aging. For a convincing substantiation of such mechanism it is necessary to show, how attenuation of bioenergetics causes the basic nocuous processes accompanying aging. It is shown earlier that the age dependent decrease in level of bioenergetics causes increase in production of reactive oxygen species by mitochondria and decrease in overall level of protein synthesis. The proof that Hayflick limit is also caused by the decrease in level of bioenergetics is presented in this article. Decrease in level of bioenergetics below certain critical level deprives a cell the ability to pass the restriction point of G1-phase of proliferative cycle. The inhibitor of cyclin-dependent kinase, p27, prevents the passage through this critical point in all normal cells. During division of normal somatic cells p27 is removed by cyclin E-Cdk2 complex. Interaction p27 with cyclin E-Cdk2 complex can have two consequences. At the normal physiological level of bioenergetics the cyclin E-Cdk2 phosphorylates p27, then the latter is destroyed by proteolytic enzymes--the cell enters in S-phase. When the programme decreases the bioenergetics level below certain value the cyclin E-Cdk2 becomes the target for p27. As a result the inhibitor evacuation stops and restriction point becomes closed--a cell enters irreversible proliferative rest.

Experimental study of electrostatic discharges of spacecraft solar array protective coatings under radiation

NASA Astrophysics Data System (ADS)

Khasanshin, Rashid; Novikov, Lev

Action of charged particles on low-conductive dielectrics causes formation of areas with a high charge density inside; their fields may give rise to development of electrostatic discharge between the charged area and the surface of the dielectric. Discharge channels are growing due to breakdown of dielectric and formation of a conducting phase. Generation of the channels is a complex stochastic process accompanied by such physical and chemical processes as ionization, gas formation, heating, and so on, which cause formation of conducting phase in a glass. That is why no quantitative theory describing formation of conductive channels has been formulated yet. The study of electrostatic discharges in dielectrics under radiation is essential both from a scientific point of view and for the solution of applied problems. In particular, interaction of a spacecraft with ambient plasma causes accumulation of electric charges on its surface producing, as a consequence, electric potential between the spacecraft surface and the plasma. For example, potentials on the surface of satellites operating on a geostationary orbit reach up to 20 kV. Elec-trostatic discharges caused by such potentials can produce not only the considerable electromag-netic interference, but also lead to the destruction of hardware components and structural ele-ments. Electrostatic charging due to electrons from the Earth’s radiation belts causes degradation of solar arrays as a result of surface and internal electrostatic discharges. In the work, surface of K-208 spacecraft solar array protective coatings irradiated by 20 and 40 keV electrons and protons has studied using by AFM methods. Traces of electrostatic dis-charges at different radiation flux densities were analyzed.

[The Process of Healing Child Physical Abuse: Sprouting and Twining].

PubMed

Chang, Hsin-Yi; Feng, Jui-Ying; Tseng, Ren-Mei

2018-06-01

Child physical abuse impacts the physical and psychological health of survivors. Healing child abuse is an essential process that helps survivors reorganize the meaning of the trauma and pursue a normal life. Considering the trauma of child physical abuse within the social context allows the experiences of individual survivors to be reflected in their process of healing. To explore the social interaction and construction process of healing experienced by survivors of child physical abuse. A qualitative research design using grounded theory was applied. Purposive and theoretical sampling was used to recruit survivors of childhood physical abuse who had experienced healing. Semi-structured, in-depth interviews were used and data were analyzed using open, axial, and selective coding. The process of healing child physical abuse in this study was a process of sprouting and twining. Three core categories emerged: thriving, relationships, and ethics. The healing process was analogous to a seed growing in poor soil, sprouting out from the ground, and striving to live by seeking support. The survivors constantly established interactive relationships with their selves and with others and struggled to keep family bonds grounded and growing within the frame of ethics. The healing process of sprouting and twining for child physical abuse survivors in Taiwan integrates thriving, relationships, and ethics. Professionals working with child-physical-abuse survivors must recognize conflicts in ethics. Strategies should be developed to assist survivors to cope with the impact of childhood trauma in order to facilitate the healing process.

[Effects of a physical restraint removal program on older people with dementia in residential care].

PubMed

Tortosa, M Ángeles; Granell, Rafael; Fuenmayor, Amadeo; Martínez, Mary

2016-01-01

To analyse the results of removing physical restraints from elderly patients with dementia living in nursing homes. This objective is part of a wider process of change in residential care. Quasi-experimental study conducted in two residences from May 2010 to May 2012. Information was collected at 7 time points and longitudinal analyses were performed. After training staff, the physical restraints in El Puig centre were phased out, while in the Conarda centre, restraints were still applied to elderly people. The main variables studied were: falls, psychotropic medication prescriptions, different indicators of mental impairment, and degree of dependence (Norton, NPI, Mini-mental, Tinetti, Barthel). In the El Puig centre all the physical restraints were removed. A slight improvement was seen in the number of falls, and their consequences. The ANOVA showed significant improvements in the centre that removed restraints in prescribing psychotropic medications, cognitive impairment, and behavioural changes. It is shown that removing physical restraints do not cause negative effects as regards the number of falls, and also positively affects the welfare and independence of elderly people (through changes in behaviour and mental impairment). Furthermore, it is demonstrated that this program must be accompanied by the reduction and control of medicines (withdrawal of the number of psychotropic prescriptions). Copyright © 2014 SEGG. Published by Elsevier Espana. All rights reserved.

Mental disorder is a cause of crime: the cornerstone of forensic psychiatry.

PubMed

Anckarsäter, Henrik; Radovic, Susanna; Svennerlind, Christer; Höglund, Pontus; Radovic, Filip

2009-01-01

The assumption that mental disorder is a cause of crime is the foundation of forensic psychiatry, but conceptual, epistemological, and empirical analyses show that neither mental nor crime, or the causation implied, are clear-cut concepts. "Mental" denotes heterogeneous aspects of a person such as inner experiences, cognitive abilities, and behaviour patterns described in a non-physical vocabulary. In psychology and psychiatry, mental describes law-bound, caused aspects of human functioning that are predictable and generalizable. Problems defined as mental disorders are end-points of dimensional inter-individual differences rather than natural categories. Deficits in cognitive faculties, such as attention, verbal understanding, impulse control, and reality assessment, may be susceptibility factors that relate to behaviours (such as crimes) by increasing the probability (risk) for a negative behaviour or constitute causes in the sense of INUS conditions (Insufficient but Non-redundant parts of Unnecessary but Sufficient conditions). Attributing causes to complex behaviours such as crimes is not an unbiased process, and mental disorders will attract disproportionate attention when it comes to explanations of behaviours that we wish to distance ourselves from. Only by rigorous interpretation of what psychiatry actually can inform us about, using empirical analyses of quantified aggressive antisocial behaviours and their possible explanatory factors, can we gain a clearer notion of the relationship between mental disorder and crime.

Uphill diffusion in multicomponent mixtures.

PubMed

Krishna, Rajamani

2015-05-21

Molecular diffusion is an omnipresent phenomena that is important in a wide variety of contexts in chemical, physical, and biological processes. In the majority of cases, the diffusion process can be adequately described by Fick's law that postulates a linear relationship between the flux of any species and its own concentration gradient. Most commonly, a component diffuses down the concentration gradient. The major objective of this review is to highlight a very wide variety of situations that cause the uphill transport of one constituent in the mixture. Uphill diffusion may occur in multicomponent mixtures in which the diffusion flux of any species is strongly coupled to that of its partner species. Such coupling effects often arise from strong thermodynamic non-idealities. For a quantitative description we need to use chemical potential gradients as driving forces. The transport of ionic species in aqueous solutions is coupled with its partner ions because of the electro-neutrality constraints; such constraints may accelerate or decelerate a specific ion. When uphill diffusion occurs, we observe transient overshoots during equilibration; the equilibration process follows serpentine trajectories in composition space. For mixtures of liquids, alloys, ceramics and glasses the serpentine trajectories could cause entry into meta-stable composition zones; such entry could result in phenomena such as spinodal decomposition, spontaneous emulsification, and the Ouzo effect. For distillation of multicomponent mixtures that form azeotropes, uphill diffusion may allow crossing of distillation boundaries that are normally forbidden. For mixture separations with microporous adsorbents, uphill diffusion can cause supra-equilibrium loadings to be achieved during transient uptake within crystals; this allows the possibility of over-riding adsorption equilibrium for achieving difficult separations.

Movie of phase separation during physics of colloids in space experiment

NASA Technical Reports Server (NTRS)

2002-01-01

Still photographs taken over 16 hours on Nov. 13, 2001, on the International Space Station have been condensed into a few seconds to show the de-mixing -- or phase separation -- process studied by the Experiment on Physics of Colloids in Space. Commanded from the ground, dozens of similar tests have been conducted since the experiment arrived on ISS in 2000. The sample is a mix of polymethylmethacrylate (PMMA or acrylic) colloids, polystyrene polymers and solvents. The circular area in the video is 2 cm (0.8 in.) in diameter. The phase separation process occurs spontaneously after the sample is mechanically mixed. The evolving lighter regions are rich in colloid and have the structure of a liquid. The dark regions are poor in colloids and have the structure of a gas. This behavior carnot be observed on Earth because gravity causes the particles to fall out of solution faster than the phase separation can occur. While similar to a gas-liquid phase transition, the growth rate observed in this test is different from any atomic gas-liquid or liquid-liquid phase transition ever measured experimentally. Ultimately, the sample separates into colloid-poor and colloid-rich areas, just as oil and vinegar separate. The fundamental science of de-mixing in this colloid-polymer sample is the same found in the annealing of metal alloys and plastic polymer blends. Improving the understanding of this process may lead to improving processing of these materials on Earth.

Phase separation during the Experiment on Physics of Colloids in Space

NASA Technical Reports Server (NTRS)

2003-01-01

Still photographs taken over 16 hours on Nov. 13, 2001, on the International Space Station have been condensed into a few seconds to show the de-mixing -- or phase separation -- process studied by the Experiment on Physics of Colloids in Space. Commanded from the ground, dozens of similar tests have been conducted since the experiment arrived on ISS in 2000. The sample is a mix of polymethylmethacrylate (PMMA or acrylic) colloids, polystyrene polymers and solvents. The circular area is 2 cm (0.8 in.) in diameter. The phase separation process occurs spontaneously after the sample is mechanically mixed. The evolving lighter regions are rich in colloid and have the structure of a liquid. The dark regions are poor in colloids and have the structure of a gas. This behavior carnot be observed on Earth because gravity causes the particles to fall out of solution faster than the phase separation can occur. While similar to a gas-liquid phase transition, the growth rate observed in this test is different from any atomic gas-liquid or liquid-liquid phase transition ever measured experimentally. Ultimately, the sample separates into colloid-poor and colloid-rich areas, just as oil and vinegar separate. The fundamental science of de-mixing in this colloid-polymer sample is the same found in the annealing of metal alloys and plastic polymer blends. Improving the understanding of this process may lead to improving processing of these materials on Earth.

Modeling Forced Imbibition Processes and the Associated Seismic Attenuation in Heterogeneous Porous Rocks

NASA Astrophysics Data System (ADS)

Solazzi, Santiago G.; Guarracino, Luis; Rubino, J. Germán.; Müller, Tobias M.; Holliger, Klaus

2017-11-01

Quantifying seismic attenuation during laboratory imbibition experiments can provide useful information toward the use of seismic waves for monitoring injection and extraction of fluids in the Earth's crust. However, a deeper understanding of the physical causes producing the observed attenuation is needed for this purpose. In this work, we analyze seismic attenuation due to mesoscopic wave-induced fluid flow (WIFF) produced by realistic fluid distributions representative of imbibition experiments. To do so, we first perform two-phase flow simulations in a heterogeneous rock sample to emulate a forced imbibition experiment. We then select a subsample of the considered rock containing the resulting time-dependent saturation fields and apply a numerical upscaling procedure to compute the associated seismic attenuation. By exploring both saturation distributions and seismic attenuation, we observe that two manifestations of WIFF arise during imbibition experiments: the first one is produced by the compressibility contrast associated with the saturation front, whereas the second one is due to the presence of patches containing very high amounts of water that are located behind the saturation front. We demonstrate that while the former process is expected to play a significant role in the case of high injection rates, which are associated with viscous-dominated imbibition processes, the latter becomes predominant during capillary-dominated processes, that is, for relatively low injection rates. We conclude that this kind of joint numerical analysis constitutes a useful tool for improving our understanding of the physical mechanisms producing seismic attenuation during laboratory imbibition experiments.

Unusually Large Runup Events

NASA Astrophysics Data System (ADS)

Garcia-Medina, G.; Ozkan-Haller, H. T.; Holman, R. A.; Ruggiero, P.

2016-02-01

Understanding the primary hydrodynamic processes that cause extreme runup events is important for the prediction of dune erosion and coastal flooding. Large runups may be caused by a superposition of physical and environmental conditions, bore-bore capture, infragravity-short wave interaction, and/or swash-backwash interaction. To investigate the conditions leading to these events we combine optical remote sensing observations (Argus) and state-of-the-art phase resolving numerical modeling (primarily NHWAVE). We evaluate runup time series derived from across-shore transects of pixel intensities in two very different beaches: Agate (Oregon, USA) and Duck (North Carolina, USA). The former is a dissipative beach where the runup is dominated by infragravity energy, whereas the latter is a reflective beach where the runup is dominated by short surface gravity waves. Phase resolving numerical models are implemented to explore an expanded parameter set and identify the mechanisms that control these large runups. Model results are in good qualitative agreement with observations. We also distinguish unexpected runups, which are defined by having an unexpectedly large excursion distance in comparison to the hourly-to-daily local runup conditions and do not necessarily represent a statistical extrema. These events pose significant safety hazards. We evaluate the relative contribution of the dominating physics to extreme and unexpected runup events.

Obesity and poverty paradox in developed countries.

PubMed

Żukiewicz-Sobczak, Wioletta; Wróblewska, Paula; Zwoliński, Jacek; Chmielewska-Badora, Jolanta; Adamczuk, Piotr; Krasowska, Ewelina; Zagórski, Jerzy; Oniszczuk, Anna; Piątek, Jacek; Silny, Wojciech

2014-01-01

Obesity is a civilization disease and the proportion of people suffering from it continues to grow, especially in the developed countries. Number of obese people in Europe has increased threefold over the last 20 years. The paradox of obesity and poverty relationship is observed especially in the developed and developing countries. In developing countries, along with economic development and income growth, the number of people with overweight and obesity is increasing. This paradox has a relationship with both the easy availability and low cost of highly processed foods containing 'empty calories' and no nutritional value. To date, this paradox has been described in the United States and the United Kingdom, although many European countries are also experiencing high percentages of obese people. Among the reasons for the growing obesity in the population of poor people are: higher unemployment, lower education level, and irregular meals. Another cause of obesity is low physical activity, which among the poor is associated with a lack of money for sports equipment. Due to the large rate of deaths caused by diseases directly linked to obesity, the governments of many countries implement prevention programmes of overweight and obesity. These programmes are based primarily on educating the public about a healthy lifestyle based on healthy eating, daily physical activity and avoiding alcohol and cigarettes.

A Physical Mechanism for the Asymmetry in Top-Down and Bottom-Up Diffusion.

NASA Astrophysics Data System (ADS)

Wyngaard, J. C.

1987-04-01

Recent large-eddy simulations of the vertical diffusion of a passive, conservative scalar through the convective boundary layer (CBL) show strikingly different eddy diffusivity profiles in the `top-down' and `bottom-up' cases. These results indicate that for a given turbulent velocity field and associated scalar flux, the mean change in scalar mixing ratio across the CBL is several times larger if the flux originates at the top of the boundary layer (i.e., in top-down diffusion) rather than at the bottom. The large-eddy simulation (LES) data show that this asymmetry is due to a breakdown of the eddy-diffusion concept.A simple updraft-downdraft model of the CBL reveals a physical mechanism that could cause this unexpected behavior. The large, positive skewness of the convectively driven vertical velocity gives an appreciably higher probability of downdrafts than updrafts; this excess probability of downdrafts, interacting with the time changes of the mean mixing ratio caused by the nonstationarity of the bottom-up and top-down diffusion processes, decreases the equilibrium value of mean mixing-ratio jump across the mixed layer in the bottom-up case and increases it in the top-down case. The resulting diffusion asymmetry agrees qualitatively with that found through LES.

Performance of the cometary experiment MUPUS on the body Earth

NASA Astrophysics Data System (ADS)

Marczewski, W.; Usowicz, B.; Schröer, K.; Seiferlin, K.; Spohn, T.

2003-04-01

Thermal experiment MUPUS for the Rosetta mission was extensively experience in field and laboratory conditions to predict its performance under physical processes available on the Earth. The goal was not guessing a cometary material in the ground but available behavior of thermal sensor responses monitoring mass and energy transfer. The processes expected on a comet are different in composition and environmental from those met on the Earth but basically similar in physics. Nature of energy powering the processes is also essentially the same - solar radiation. Several simple laboratory experiments with freezing and thawing with water ice, with mixture of water and oil and water layers strongly diverged by salinity revealed capability of recognition layered structure of the medium under test. More over effects of slow convection and latent heat related to the layers are also observed well. Cometary environment without atmosphere makes process of sublimation dominant. Open air conditions on the Earth may also offer a change of state in matter but between different phases. Learning temperature gradient in snow layers under thawing show that effects stimulated by a cause of daily cycling may be detected thermally. Results from investigations in snow made on Spitzbergen are good proofs on capability of the method. Relevance of thermal effects to heat powered processes of mass transport in the matter of ground is meaningful for the cometary experiment of MUPUS and for Earth sciences much concerned on water, gas and solid matter transport in the terrestrial ground. Results leading to energy balance studied on the Earth surface may be interesting also for the experiment on the comet and are to be discussed.

Solid recovered fuel production from biodegradable waste in grain processing industry.

PubMed

Kliopova, Irina; Staniskis, Jurgis Kazimieras; Petraskiene, Violeta

2013-04-01

Management of biodegradable waste is one of the most important environmental problems in the grain-processing industry since this waste cannot be dumped anymore due to legal requirements. Biodegradable waste is generated in each stage of grain processing, including the waste-water and air emissions treatment processes. Their management causes some environmental and financial problems. The majority of Lithuanian grain-processing enterprises own and operate composting sites, but in Lithuania the demand for compost is not given. This study focused on the analysis of the possibility of using biodegradable waste for the production of solid recovered fuel, as a local renewable fuel with the purpose of increasing environmental performance and decreasing the direct costs of grain processing. Experimental research with regard to a pilot grain-processing plant has proven that alternative fuel production will lead to minimizing of the volume of biodegradable waste by 75% and the volume of natural gas for heat energy production by 62%. Environmental indicators of grain processing, laboratory analysis of the chemical and physical characteristics of biodegradable waste, mass and energy balances of the solid recovered fuel production, environmental and economical benefits of the project are presented and discussed herein.

The Singaporean public beliefs about the causes of mental illness: results from a multi-ethnic population-based study.

PubMed

Pang, S; Subramaniam, M; Lee, S P; Lau, Y W; Abdin, E; Chua, B Y; Picco, L; Vaingankar, J A; Chong, S A

2017-04-03

To identify the common causal beliefs of mental illness in a multi-ethnic Southeast Asian community and describe the sociodemographic associations to said beliefs. The factor structure to the causal beliefs scale is explored. The causal beliefs relating to five different mental illnesses (alcohol abuse, depression, obsessive-compulsive disorder (OCD), dementia and schizophrenia) and desire for social distance are also investigated. Data from 3006 participants from a nationwide vignette-based study on mental health literacy were analysed using factor analysis and multiple logistic regression to address the aims. Participants answered questions related to sociodemographic information, causal beliefs of mental illness and their desire for social distance towards those with mental illness. Physical causes, psychosocial causes and personality causes were endorsed by the sample. Sociodemographic differences including ethnic, gender and age differences in causal beliefs were found in the sample. Differences in causal beliefs were shown across different mental illness vignettes though psychosocial causes was the most highly attributed cause across vignettes (endorsed by 97.9% of respondents), followed by personality causes (83.5%) and last, physical causes (37%). Physical causes were more likely to be endorsed for OCD, depression and schizophrenia. Psychosocial causes were less often endorsed for OCD. Personality causes were less endorsed for dementia but more associated with depression. The factor structure of the causal beliefs scale is not entirely the same as that found in previous research. Further research on the causal beliefs endorsed by Southeast Asian communities should be conducted to investigate other potential causes such as biogenetic factors and spiritual/supernatural causes. Mental health awareness campaigns should address causes of mental illness as a topic. Lay beliefs in the different causes must be acknowledged and it would be beneficial for the public to be informed of the causes of some of the most common mental illnesses in order to encourage help-seeking and treatment compliance.

The synthesis of carbon electrode supercapacitor from durian shell based on variations in the activation time

NASA Astrophysics Data System (ADS)

Taer, E.; Dewi, P.; Sugianto, Syech, R.; Taslim, R.; Salomo, Susanti, Y.; Purnama, A.; Apriwandi, Agustino, Setiadi, R. N.

2018-02-01

The synthesis of carbon electrode from durian shell based on variations in the activation time has been carried out. Synthesis of carbon electrode was started by a carbonization process at a temperature of 600°C in nitrogen gas and then followed by physical activation process using water vapor at a temperature of 900°C by varying time of 1, 2 and 3 h. All of the variations of the samples were chemically activated using an activator of ZnCl2 with a concentration of 0.4 M. The physical properties such as density, surface morphology, degree of crystallinity and elemental content were analyzed. Moreover, the electrochemical properties such as specific capacitance of supercapacitor cells were studied using Cyclic Voltammetry methods. The density, stack height and carbon content were increased as activation time increases, while the specific capacitance of the supercapacitor cell decreases against the increase of activation time. Specific capacitances for 1, 2 and 3 h activation time are 88.39 F/g, 80.08 F/g and 74.61 F/g, respectively. Based on the surface morphology study it was shown that the increased in activation time causes narrowing of the pores between particles.

Understanding stellar activity and flares to search for Earth-like exoplanets

NASA Astrophysics Data System (ADS)

Del Sordo, Fabio

2015-08-01

The radial velocity method is a powerful way to search for exoplanetary systems and it led to many discoveries of exoplanets in the last 20 years. Nowadays, understanding stellar activity, flares and noise is a key factor for achieving a substantial improvement in such technique.Radial-velocity data are time-series containing the effect of both planets and stellar disturbances: the detection of Earth-like planets requires to improve the signal-to-noise ratio, i.e. it is central to understand the noise present in the data. Noise is caused by physical processes which operate on different time-scales, oftentimes acting in a non-periodic fashion. We present here an approach to such problem: to look for multifractal structures in the time-series coming from radial velocity measurements, identifying the underlying long-range correlations and fractal scaling properties, connecting them to the underlying physical processes (stellar oscillations, stellar wind, granulation, rotation, magnetic activity). This method has been previously applied to satellite data related to Arctic sea albedo, relevant for identify trends and noise in the Arctic sea ice (Agarwal, Moon, Wettlaufer, 2012). Here we suggest to use such analysis for exoplanetary data related to possible Earth-like planets.

Rockfall hazard analysis using LiDAR and spatial modeling

NASA Astrophysics Data System (ADS)

Lan, Hengxing; Martin, C. Derek; Zhou, Chenghu; Lim, Chang Ho

2010-05-01

Rockfalls have been significant geohazards along the Canadian Class 1 Railways (CN Rail and CP Rail) since their construction in the late 1800s. These rockfalls cause damage to infrastructure, interruption of business, and environmental impacts, and their occurrence varies both spatially and temporally. The proactive management of these rockfall hazards requires enabling technologies. This paper discusses a hazard assessment strategy for rockfalls along a section of a Canadian railway using LiDAR and spatial modeling. LiDAR provides accurate topographical information of the source area of rockfalls and along their paths. Spatial modeling was conducted using Rockfall Analyst, a three dimensional extension to GIS, to determine the characteristics of the rockfalls in terms of travel distance, velocity and energy. Historical rockfall records were used to calibrate the physical characteristics of the rockfall processes. The results based on a high-resolution digital elevation model from a LiDAR dataset were compared with those based on a coarse digital elevation model. A comprehensive methodology for rockfall hazard assessment is proposed which takes into account the characteristics of source areas, the physical processes of rockfalls and the spatial attribution of their frequency and energy.

Aloe vera bathing improved physical and humoral protection in breeding stock after induced spawning in matrinxã (Brycon amazonicus).

PubMed

Zanuzzo, Fábio S; Zaiden, Sérgio F; Senhorini, José A; Marzocchi-Machado, Cleni M; Urbinati, Elisabeth C

2015-07-01

In this study, we show that induced spawning causes stress, an intense loss of epithelia and immunosuppression, decreasing physical and humoral protection in fish, effects that were prevented or improved in fish bathed with Aloe vera. A. vera has several medicinal properties, including wound healing and immunostimulatory effects, which we observed in this study. Fish bathed with A. vera had a higher number of epidermal goblet cells and, in general, an improved wound healing rate compared with the control after induced spawning. These effects might be related to (1) the stimulation of leukocyte activity, represented here by the increased leukocyte respiratory activity triggered by A. vera (leukocytes are recognized as playing an important role in wound repair); (2) the antimicrobial properties of A. vera, which decrease wound infection and accelerate the healing process; and (3) several mechanisms that explain the healing effect of A. vera (increased collagen synthesis, rate of epithelialization, and anti-inflammatory and moisturizing effects). Our results also suggest that caution is necessary during the induced spawning process, especially during stripping, and A. vera bathing is recommended after intensive aquaculture operations. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Capabilities of Chaos and Complexity

PubMed Central

Abel, David L.

2009-01-01

To what degree could chaos and complexity have organized a Peptide or RNA World of crude yet necessarily integrated protometabolism? How far could such protolife evolve in the absence of a heritable linear digital symbol system that could mutate, instruct, regulate, optimize and maintain metabolic homeostasis? To address these questions, chaos, complexity, self-ordered states, and organization must all be carefully defined and distinguished. In addition their cause-and-effect relationships and mechanisms of action must be delineated. Are there any formal (non physical, abstract, conceptual, algorithmic) components to chaos, complexity, self-ordering and organization, or are they entirely physicodynamic (physical, mass/energy interaction alone)? Chaos and complexity can produce some fascinating self-ordered phenomena. But can spontaneous chaos and complexity steer events and processes toward pragmatic benefit, select function over non function, optimize algorithms, integrate circuits, produce computational halting, organize processes into formal systems, control and regulate existing systems toward greater efficiency? The question is pursued of whether there might be some yet-to-be discovered new law of biology that will elucidate the derivation of prescriptive information and control. “System” will be rigorously defined. Can a low-informational rapid succession of Prigogine’s dissipative structures self-order into bona fide organization? PMID:19333445

Surface and interface sciences of Li-ion batteries. -Research progress in electrode-electrolyte interface-

NASA Astrophysics Data System (ADS)

Minato, Taketoshi; Abe, Takeshi

2017-12-01

The application potential of Li-ion batteries is growing as demand increases in different fields at various stages in energy systems, in addition to their conventional role as power sources for portable devices. In particular, applications in electric vehicles and renewable energy storage are increasing for Li-ion batteries. For these applications, improvements in battery performance are necessary. The Li-ion battery produces and stores electric power from the electrochemical redox reactions between the electrode materials. The interface between the electrodes and electrolyte strongly affects the battery performance because the charge transfer causing the electrode redox reaction begins at this interface. Understanding of the surface structure, electronic structure, and chemical reactions at the electrode-electrolyte interface is necessary to improve battery performance. However, the interface is located between the electrode and electrolyte materials, hindering the experimental analysis of the interface; thus, the physical properties and chemical processes have remained poorly understood until recently. Investigations of the physical properties and chemical processes at the interface have been performed using advanced surface science techniques. In this review, current knowledge and future research prospects regarding the electrode-electrolyte interface are described for the further development of Li-ion batteries.

Twinning, Epitaxy and Domain Switching in Ferroelastic Inclusion Compounds

NASA Technical Reports Server (NTRS)

Hollingsworth, Mark D.; Peterson, Matthew L.

2003-01-01

Our research is in the area of solid-state organic chemistry, which lies at the interface between physical organic chemistry and materials science. We use crystalline solids as models to probe fundamental issues about physical processes, molecular interactions and chemical reactions that are important for fabrication, stabilization and application of technological materials. Much of our most recent work has focused on the phenomena of ferroelastic and ferroelectric domain switching, in which application of an external force or electric field to a crystal causes the molecules inside the crystal to reorient, in tandem, to a new orientational state. To better understand and control the domain switching process, we have designed and synthesized over twenty closely related, ferroelastic organic crystals. Our approach has been to use crystalline inclusion compounds, in which one molecule (the guest) is trapped within the crystalline framework of a second molecule (the host). By keeping the host constant and varying the proportions and kinds of guests, it has been possible to tailor these materials so that domain switching is rapid and reversible (which is desirable for high technology applications). Inclusion compounds therefore serve as powerful systems for understanding the specific molecular mechanisms that control domain switching.

Computational fluid dynamics and frequency-dependent finite-difference time-domain method coupling for the interaction between microwaves and plasma in rocket plumes

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

Kinefuchi, K.; Funaki, I.; Shimada, T.

Under certain conditions during rocket flights, ionized exhaust plumes from solid rocket motors may interfere with radio frequency transmissions. To understand the relevant physical processes involved in this phenomenon and establish a prediction process for in-flight attenuation levels, we attempted to measure microwave attenuation caused by rocket exhaust plumes in a sea-level static firing test for a full-scale solid propellant rocket motor. The microwave attenuation level was calculated by a coupling simulation of the inviscid-frozen-flow computational fluid dynamics of an exhaust plume and detailed analysis of microwave transmissions by applying a frequency-dependent finite-difference time-domain method with the Drude dispersion model.more » The calculated microwave attenuation level agreed well with the experimental results, except in the case of interference downstream the Mach disk in the exhaust plume. It was concluded that the coupling estimation method based on the physics of the frozen plasma flow with Drude dispersion would be suitable for actual flight conditions, although the mixing and afterburning in the plume should be considered depending on the flow condition.« less

A Fuzzy analytical hierarchy process approach in irrigation networks maintenance

NASA Astrophysics Data System (ADS)

Riza Permana, Angga; Rintis Hadiani, Rr.; Syafi'i

2017-11-01

Ponorogo Regency has 440 Irrigation Area with a total area of 17,950 Ha. Due to the limited budget and lack of maintenance cause decreased function on the irrigation. The aim of this study is to make an appropriate system to determine the indices weighted of the rank prioritization criteria for irrigation network maintenance using a fuzzy-based methodology. The criteria that are used such as the physical condition of irrigation networks, area of service, estimated maintenance cost, and efficiency of irrigation water distribution. 26 experts in the field of water resources in the Dinas Pekerjaan Umum were asked to fill out the questionnaire, and the result will be used as a benchmark to determine the rank of irrigation network maintenance priority. The results demonstrate that the physical condition of irrigation networks criterion (W1) = 0,279 has the greatest impact on the assessment process. The area of service (W2) = 0,270, efficiency of irrigation water distribution (W4) = 0,249, and estimated maintenance cost (W3) = 0,202 criteria rank next in effectiveness, respectively. The proposed methodology deals with uncertainty and vague data using triangular fuzzy numbers, and, moreover, it provides a comprehensive decision-making technique to assess maintenance priority on irrigation network.

Correlative STED and Atomic Force Microscopy on Live Astrocytes Reveals Plasticity of Cytoskeletal Structure and Membrane Physical Properties during Polarized Migration

PubMed Central

Curry, Nathan; Ghézali, Grégory; Kaminski Schierle, Gabriele S.; Rouach, Nathalie; Kaminski, Clemens F.

2017-01-01

The plasticity of the cytoskeleton architecture and membrane properties is important for the establishment of cell polarity, adhesion and migration. Here, we present a method which combines stimulated emission depletion (STED) super-resolution imaging and atomic force microscopy (AFM) to correlate cytoskeletal structural information with membrane physical properties in live astrocytes. Using STED compatible dyes for live cell imaging of the cytoskeleton, and simultaneously mapping the cell surface topology with AFM, we obtain unprecedented detail of highly organized networks of actin and microtubules in astrocytes. Combining mechanical data from AFM with optical imaging of actin and tubulin further reveals links between cytoskeleton organization and membrane properties. Using this methodology we illustrate that scratch-induced migration induces cytoskeleton remodeling. The latter is caused by a polarization of actin and microtubule elements within astroglial cell processes, which correlates strongly with changes in cell stiffness. The method opens new avenues for the dynamic probing of the membrane structural and functional plasticity of living brain cells. It is a powerful tool for providing new insights into mechanisms of cell structural remodeling during physiological or pathological processes, such as brain development or tumorigenesis. PMID:28469559

Needs of ergonomic design at control units in production industries.

PubMed

Levchuk, I; Schäfer, A; Lang, K-H; Gebhardt, Hj; Klussmann, A

2012-01-01

During the last decades, an increasing use of innovative technologies in manufacturing areas was monitored. A huge amount of physical workload was replaced by the change from conventional machine tools to computer-controlled units. CNC systems spread in current production processes. Because of this, machine operators today mostly have an observational function. This caused increasing of static work (e.g., standing, sitting) and cognitive demands (e.g., process observation). Machine operators have a high responsibility, because mistakes may lead to human injuries as well as to product losses - and in consequence may lead to high monetary losses (for the company) as well. Being usable often means for a CNC machine being efficient. An intuitive usability and an ergonomic organization of CNC workplaces can be an essential basis to reduce the risk of failures in operation as well as physical complaints (e.g. pain or diseases because of bad body posture during work). In contrast to conventional machines, CNC machines are equipped both with hardware and software. An intuitive and clear-sighted operating of CNC systems is a requirement for quick learning of new systems. Within this study, a survey was carried out among trainees learning the operation of CNC machines.