Precious Metals in Automotive Technology: An Unsolvable Depletion Problem?

Directory of Open Access Journals (Sweden)

Ugo Bardi

2014-04-01

Full Text Available Since the second half of the 20th century, various devices have been developed in order to reduce the emissions of harmful substances at the exhaust pipe of combustion engines. In the automotive field, the most diffuse and best known device of this kind is the “three way” catalytic converter for engines using the Otto cycle designed to abate the emissions of carbon monoxide, nitrogen oxides and unburnt hydrocarbons. These catalytic converters can function only by means of precious metals (mainly platinum, rhodium and palladium which exist in a limited supply in economically exploitable ores. The recent increase in prices of all mineral commodities is already making these converters significantly expensive and it is not impossible that the progressive depletion of precious metals will make them too expensive for the market of private cars. The present paper examines how this potential scarcity could affect the technology of road transportation worldwide. We argue that the supply of precious metals for automotive converters is not at risk in the short term, but that in the future it will not be possible to continue using this technology as a result of increasing prices generated by progressive depletion. Mitigation methods such as reducing the amounts of precious metals in catalysts, or recycling them can help but cannot be considered as a definitive solution. We argue that precious metal scarcity is a critical factor that may determine the future development of road transportation in the world. As the problem is basically unsolvable in the long run, we must explore new technologies for road transportation and we conclude that it is likely that the clean engine of the future will be electric and powered by batteries.

Unsolved Problems of Iran's Nuclear Program And Prospects in the light of Role of Parties to an Entente

Energy Technology Data Exchange (ETDEWEB)

Kim, Min Soo; Kim, Jae San [Korea Institute of Nuclear Nonproliferation and Control, Daejeon (Korea, Republic of)

2009-05-15

From past to present, Iran have been focused by international society and still have continued their enrichment activity despite of many sanctions. It is barely easy to solve this situation and to negotiate between related countries. Because there are many factors to influence this. New president of U.S. Barack Obama could be a great deal of factor for solving Iran's nuclear issue as well. From this point of view, following Iran's unsolved problems of nuclear program could be helpful to understand the situation and what the key point to solve it, and forecast the future with surrounding political and regional factors.

Exposure to Unsolvable Anagrams Impairs Performance on the Iowa Gambling Task

Directory of Open Access Journals (Sweden)

Katrin Starcke

2017-06-01

Full Text Available Recent research indicates that external manipulations, such as stress or mood induction, can affect decision-making abilities. In the current study, we investigated whether the exposure to an unsolvable task affected subsequent performance on the Iowa Gambling Task. Participants were randomly assigned to a condition in which they were exposed to unsolvable anagrams (n = 20, or a condition in which they worked on solvable anagrams (n = 22. Afterwards, all participants played the Iowa Gambling Task, a prominent task that measures decision making under uncertain conditions with no explicit rules for gains and losses. In this task, it is essential to process feedback from previous decisions. The results demonstrated that participants who worked on unsolvable anagrams made more disadvantageous decisions on the Iowa Gambling Task than the other participants. In addition, a significant gender effect was observed: Males who worked on unsolvable anagrams made a more disadvantageous decisions than the other male participants. Females who worked on unsolvable anagrams also made more disadvantageous decision than the other female participants, but differences were small and not significant. We conclude that the exposure to unsolvable anagrams induced the experience of uncontrollability which can elicit stress and learned helplessness. Stress and learned helplessness might have reduced the ability to learn from the given feedback, particularly in male participants. We assume that in real life, uncontrollable challenges that last longer than a single experimental manipulation can affect decision making severely, at least in males.

Application of Radiotracer Technology on Solving the Unsolved Leak in Lift Pit

International Nuclear Information System (INIS)

Mohd Fitri Abdul Rahman; Jaafar Abdullah; Hearie Hassan

2016-01-01

Radiotracers have been used in many fields to optimize processes, solve problems, improve product quality, save energy and reduce pollution. The radiotracer technology is a proven reliable technique and recognized by many sectors such as medical, industrial and environmental. In this work, an unsolved leak problem was present in lift pit within a building in Malaysia. Many techniques have applied such as dye techniques, chemical analyses and engineering plaster to overcome the problem. Unfortunately, none of the techniques solve the problem. Radiotracer was used to find the unidentified source of leak. Basically, Technetium (Tc-99m) has been injected to the several injection points and flow of the tracer was monitored with radiation detectors that have been placed at various locations. The results were successful and pinpoint the problems. (author)

The Somerton man : an unsolved history

Directory of Open Access Journals (Sweden)

Balint, Ruth

2010-01-01

Full Text Available The case of the unknown man who died mysteriously at Somerton Beach in South Australia in 1948 remains an open police investigation, although the trail today has grown fairly cold. Revisiting the case, and the responses the mystery of his person have elicited, enables a special historical insight into Australia’s postwar society, and the ways in which the past is continually reshaped by the subjectivities of the present. Further, an unsolved case such as this provides for a unique kind of historical project. The limitations of a history without a coherent centre are myriad, yet so are the possibilities. In this article, I explore the possibilities of an ‘unsolved history’, a history of dead ends, and argue that it is the very unknowable-ness of the Somerton Man that allows for a perception of history as multi-dimensional and complex.

The Somerton Man: An Unsolved History

Directory of Open Access Journals (Sweden)

Ruth Balint

2010-09-01

Full Text Available The case of the unknown man who died mysteriously at Somerton Beach in South Australia in 1948 remains an open police investigation, although the trail today has grown fairly cold. Revisiting the case, and the responses the mystery of his person have elicited, enables a special historical insight into Australia’s postwar society, and the ways in which the past is continually reshaped by the subjectivities of the present. Further, an unsolved case such as this provides for a unique kind of historical project. The limitations of a history without a coherent centre are myriad, yet so are the possibilities.  In this article, I explore the possibilities of an ‘unsolved history’, a history of dead ends, and argue that it is the very unknowable-ness of the Somerton Man that allows for a perception of history as multi-dimensional and complex.

Nonlinear Multidimensional Assignment Problems Efficient Conic Optimization Methods and Applications

Science.gov (United States)

2015-06-24

WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Arizona State University School of Mathematical & Statistical Sciences 901 S...SUPPLEMENTARY NOTES 14. ABSTRACT The major goals of this project were completed: the exact solution of previously unsolved challenging combinatorial optimization... combinatorial optimization problem, the Directional Sensor Problem, was solved in two ways. First, heuristically in an engineering fashion and second, exactly

Nuclear waste - the unsolved problem

International Nuclear Information System (INIS)

Boyle, S.

1986-01-01

Nuclear waste is identified and the problems created by reprocessing are mentioned. The disposal option for low, intermediate and high-level radioactive wastes are discussed. Sites where disposal has taken place have been found to be unsatisfactory because of contamination and radionuclide migration. The Nuclear Industry Radioactive Waste Executive (NIREX) is not seen as having any more credibility than the other nuclear authorities involved (BNFL, UKAEA, CEGB). Until an adequate, publically acceptable, method of disposing of the wastes already created has been found the author states that no more should be created. (U.K.)

Off-Label Drug Use in Pediatric Practice: Unsolved Problems

Directory of Open Access Journals (Sweden)

A. R. Titova

2015-01-01

Full Text Available The widespread «off-label» drug use and the prescribing of unlicensed medicines in pediatric practice is a major health problem. The authors discuss actual regulatory and legal issues of «off-label» drug use in children in the US, Europe and Russia. The results of different population-based studies from many countries, showing the structure and frequency of «off-label» drug use in children, are summarized in this article. It is shown that such practice increases the risk of adverse drug reactions. The authors offer practical recommendations for a safer use of drugs in pediatric practice. The priority issue is conducting high quality clinical trials with the participation of children, improving national pharmacovigilance and the monitoring of off-label drug use, developing pediatric formularies, improving doctors’ knowledge and awareness of safety and efficacy of medicines in pediatric population.

The Somerton Man: An Unsolved History

OpenAIRE

Balint, Ruth

2010-01-01

The case of the unknown man who died mysteriously at Somerton Beach in South Australia in 1948 remains an open police investigation, although the trail today has grown fairly cold. Revisiting the case, and the responses the mystery of his person have elicited, enables a special historical insight into Australia’s postwar society, and the ways in which the past is continually reshaped by the subjectivities of the present. Further, an unsolved case such as this provides for a unique kind ...

Solved and unsolved problems of chemical graph theory

International Nuclear Information System (INIS)

Trinajstic, N.; Klein, D.J.; Randic, M.

1986-01-01

The development of several novel graph theoretical concepts and their applications in different branches of chemistry are reviewed. After a few introductory remarks they follow with an outline of selected important graph theoretical invariants, introducing some new results and indicating some open problems. They continue with discussing the problem of graph characterization and construction of graphs of chemical interest, with a particular emphasis on large systems. Finally they consider various problems and difficulties associated with special subgraphs, including subgraphs representing Kekule valence structures. The paper ends with a brief review of structure-property and structure-activity correlations, the topic which is one of prime motivations for application of graph theory to chemistry

THE CERVICAL CANCER SCREENING - UNSOLVED PROBLEMS

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A. D. Kaprin

2015-01-01

Full Text Available The problem of cervical cancer (CC for many decades continues to be the center of attention leading foreign and domestic oncologists. Malignant cervical tumors occupy the leading position among malignant neoplasms of reproductive system in women, second only to breast cancer, despite having far more effective screening compared with this disease. On predictive expert estimates (taking into account population growth and the expected increase in life expectancy by 2020 in developing countries, the rising incidence and prevalence of cervical cancer is 40%, while in developed countries - 11%. If we do not perform timely interventions for prevention and treatment of cervical cancer, after 2050 cervical cancer every year in the world will become sick 1 million women. In the last decade inRussiathere has been a gradual increase in the incidence of cervical cancer: average annual growth rate of 2.21%, General 25,18%. Cervical cancer is one of nosological forms that meet all the requirements of population-based screening. The current Russian normative documents do not give clear answers to questions concerning the age of onset of cervical cancer screening and the time interval between tests, no clear program organized cytological screening of cervical cancer.

The puzzling unsolved mysteries of liquid water: Some recent progress

Science.gov (United States)

Stanley, H. E.; Kumar, P.; Xu, L.; Yan, Z.; Mazza, M. G.; Buldyrev, S. V.; Chen, S.-H.; Mallamace, F.

2007-12-01

Water is perhaps the most ubiquitous, and the most essential, of any molecule on earth. Indeed, it defies the imagination of even the most creative science fiction writer to picture what life would be like without water. Despite decades of research, however, water's puzzling properties are not understood and 63 anomalies that distinguish water from other liquids remain unsolved. We introduce some of these unsolved mysteries, and demonstrate recent progress in solving them. We present evidence from experiments and computer simulations supporting the hypothesis that water displays a special transition point (which is not unlike the “tipping point” immortalized by Malcolm Gladwell). The general idea is that when the liquid is near this “tipping point,” it suddenly separates into two distinct liquid phases. This concept of a new critical point is finding application to other liquids as well as water, such as silicon and silica. We also discuss related puzzles, such as the mysterious behavior of water near a protein.

Neural tube defects – recent advances, unsolved questions and controversies

Science.gov (United States)

Copp, Andrew J.; Stanier, Philip; Greene, Nicholas D. E.

2014-01-01

Neural tube defects (NTDs) are severe congenital malformations affecting around 1 in every 1000 pregnancies. Here we review recent advances and currently unsolved issues in the NTD field. An innovation in clinical management has come from the demonstration that closure of open spina bifida lesions in utero can diminish neurological dysfunction in children. Primary prevention by folic acid has been enhanced through introduction of mandatory food fortification in some countries, although not yet in UK. Genetic predisposition comprises the majority of NTD risk, and genes that regulate folate one-carbon metabolism and planar cell polarity have been strongly implicated. The sequence of human neural tube closure events remains controversial, but study of mouse NTD models shows that anencephaly, open spina bifida and craniorachischisis result from failure of primary neurulation, while skin-covered spinal dysraphism results from defective secondary neurulation. Other ‘NTD’ malformations, such as encephalocele, are likely to be post-neurulation disorders. PMID:23790957

Molecular Phylogenetics: Mathematical Framework and Unsolved Problems

Science.gov (United States)

Xia, Xuhua

Phylogenetic relationship is essential in dating evolutionary events, reconstructing ancestral genes, predicting sites that are important to natural selection, and, ultimately, understanding genomic evolution. Three categories of phylogenetic methods are currently used: the distance-based, the maximum parsimony, and the maximum likelihood method. Here, I present the mathematical framework of these methods and their rationales, provide computational details for each of them, illustrate analytically and numerically the potential biases inherent in these methods, and outline computational challenges and unresolved problems. This is followed by a brief discussion of the Bayesian approach that has been recently used in molecular phylogenetics.

To the confinement problem

International Nuclear Information System (INIS)

Savvidi, G.K.

1985-01-01

Such a viewpoint is proposed for separation of the physical quantities into observable and unobservable ones, when the latters are connected with the Hermitian operator for which the eigenvalue problem is unsolvable

The Caterer's Problem.

Science.gov (United States)

Krause, Eugene F.

1983-01-01

An approach to teaching problem solving to preservice and in-service middle school teachers is described. They examined an unsolved question as a class research project. The process of developing the solution is detailed, and difficulties contained within the process are noted. (MP)

Neutrino statistics: elementary problems and some applications

Energy Technology Data Exchange (ETDEWEB)

Kuchowicz, B

1973-01-01

The treatment of neutrinos includes neutrinos in statistical equilibrium, mathematical refinements, application to stars, the relic neutrinos in cosmology, and some unsolved problems and prospects. (JFP)

Remotely Telling Humans and Computers Apart: An Unsolved Problem

Science.gov (United States)

Hernandez-Castro, Carlos Javier; Ribagorda, Arturo

The ability to tell humans and computers apart is imperative to protect many services from misuse and abuse. For this purpose, tests called CAPTCHAs or HIPs have been designed and put into production. Recent history shows that most (if not all) can be broken given enough time and commercial interest: CAPTCHA design seems to be a much more difficult problem than previously thought. The assumption that difficult-AI problems can be easily converted into valid CAPTCHAs is misleading. There are also some extrinsic problems that do not help, especially the big number of in-house designs that are put into production without any prior public critique. In this paper we present a state-of-the-art survey of current HIPs, including proposals that are now into production. We classify them regarding their basic design ideas. We discuss current attacks as well as future attack paths, and we also present common errors in design, and how many implementation flaws can transform a not necessarily bad idea into a weak CAPTCHA. We present examples of these flaws, using specific well-known CAPTCHAs. In a more theoretical way, we discuss the threat model: confronted risks and countermeasures. Finally, we introduce and discuss some desirable properties that new HIPs should have, concluding with some proposals for future work, including methodologies for design, implementation and security assessment.

Heart ischemic disease and longevity: unsolved problems

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Markova T.Yu.

2015-03-01

Full Text Available The purpose of the study was to estimate clinical signs and course of coronary heart disease in long-livers and centenarians. Material and Methods. The study included overall population of Saratov — Engels agglomeration's long-livers (>=90 years old, n=198. Results. The rates of major clinical forms of coronary heart disease were detected: atrial fibrillation — 10.6%, chronic heart failure (with preserved ejection fraction — 10.1 % and angina — 5.1 %. Myocardial infarction was verified in 9.6% of long-livers. Myocardial scar criteria prevailed over myocardial infarction history. Received data corroborated dissolving phenomena of coronary heart disease and noninsulin dependent diabetes mellitus in long-livers. Gender differences in electrophysiological parameters were detected in long-livers. Centenarians with the history of myocardial infarction preserved a satisfactory level of physical activity. Conclusion. Received data confirm a presence of an excessive security: prevention of coronary heart disease manifestation and progression in longevity. Long-livers should be considered as a natural model of an antiatherogenic factors and mechanisms.

Isolated thoughts and feelings and unsolved concerns

DEFF Research Database (Denmark)

Carstensøe-Seidenfaden, Pernille; Teilmann, Grete Katrine; Kensing, Finn

2017-01-01

often experience deteriorating glycaemic control and distress. Parents are important in adolescents' ability to self-manage type 1 diabetes, but they report anxiety and frustrations. A better understanding of the challenges adolescents and parents face, in relation to the daily self-management of type 1...... diabetes, is important to improve clinical practice. DESIGN: A qualitative explorative study using visual storytelling as part of individual interviews. METHODS: A purposive sample of nine adolescents and their parents (seven mothers, six fathers) took photographs illustrating their experiences living...... and challenges unsolved. CONCLUSIONS: The concerns and challenges adolescents and their parents face in the transition from child- to adulthood are still present despite new treatment modalities. Parents are fundamental in supporting the adolescents' self-management-work; however, the parties have unspoken...

The problem of creation of radiation monitoring system

International Nuclear Information System (INIS)

Pilipchak, S.I.

1990-01-01

The review of problem of radiation monitoring system (RMS) in the territory of the country is presented. Unsolved problems are discussed which are divided into three groups: the organization of structures in RMS; implementation of automated RMS; the solution of scientific problems of global monitoring of radiation situation. 12 refs.; 1 tab

ACTUAL AND UNSOLVED PROBLEMS OF FUNCTIONAL CONSTIPATIONS IN INFANTS

Directory of Open Access Journals (Sweden)

N.I. Ursova

2010-01-01

Full Text Available The article presents modern point of view on the problem of functional constipations in infants. It describes peculiarities of digestion, intestinal micro biocenosis in healthy infants, the ways of its correction. Author indicates principles of choice of defined drugs effective on early stages of postnatal development. The advantages of osmotic laxative — macrogol 4,000 (Forlax in treatment of functional constipations in children are presented.Key words: infants, large intestine, functional disorders, nutrition, laxatives, macrogol, prebiotics.(Voprosy sovremennoi pediatrii — Current Pediatrics. – 2010;9(3:63-69

Numerical problems in physics

CERN Document Server

Singh, Devraj

2015-01-01

Numerical Problems in Physics, Volume 1 is intended to serve the need of the students pursuing graduate and post graduate courses in universities with Physics and Materials Science as subject including those appearing in engineering, medical, and civil services entrance examinations. KEY FEATURES: * 29 chapters on Optics, Wave & Oscillations, Electromagnetic Field Theory, Solid State Physics & Modern Physics * 540 solved numerical problems of various universities and ompetitive examinations * 523 multiple choice questions for quick and clear understanding of subject matter * 567 unsolved numerical problems for grasping concepts of the various topic in Physics * 49 Figures for understanding problems and concept

Looking back at 'looking back': operationalising referential gaze for dingoes in an unsolvable task.

Science.gov (United States)

Smith, Bradley Philip; Litchfield, Carla Anita

2013-11-01

This paper examined the performance of dingoes (Canis dingo) on the rope-pulling task, previously used by Miklósi et al. (Curr Biol 13:763-766, 2003) to highlight a key distinction in the problem-solving behaviour of wolves compared to dogs when in the company of humans. That is, when dogs were confronted with an unsolvable task, following a solvable version of the task they looked back or gazed at the human, whereas, wolves did not. We replicated the rope-pulling task using 12 sanctuary-housed dingoes and used the Miklósi et al. (Curr Biol 13:763-766, 2003) definition of looking back behaviour to analyse the data. However, at least three different types of look backs were observed in our study. We, then developed a more accurate operational definition of looking back behaviour that was task specific and reanalysed the data. We found that the operational definition employed greatly influences the results, with vague definitions potentially overestimating the prevalence of looking back behaviour. Thus, caution must be taken when interpreting the results of studies utilising looking back as behaviour linked to assistance seeking during problem solving. We present a more stringent definition and make suggestions for future research.

Unsolved issues related to thermal-hydraulics in the suppression chamber during Fukushima Daiichi accident progressions

International Nuclear Information System (INIS)

Mizokami, Shinya; Yamada, Daichi; Honda, Takeshi; Yamauchi, Daisuke; Yamanaka, Yasunori

2016-01-01

On 11 March 2011, the Great East Japan Earthquake and Tsunami hit the Fukushima Daiichi Nuclear Power Station. The Fukushima Daiichi Units 1-3 lost all DC and AC power supplies, which set in motion a chain of events that led to releases of radioactivity to the environment. Since then, TEPCO has made many efforts to investigate the accident progressions and the status of the reactors and containment vessels. However, there still exist several tens of unsolved issues to be investigated for the fully understanding of the accident. In this paper, we introduce the unsolved issues related to thermal-hydraulics in the suppression chamber during the Fukushima Daiichi accident progressions. Especially, in Units 2 and 3, there are possibilities that thermal stratification inside their suppression chambers played an important role. It is important that these phenomena are addressed following both theoretical and experimental approaches as support to severe accident simulations. (author)

Solved problems in electrochemistry

International Nuclear Information System (INIS)

Piron, D.L.

2004-01-01

This book presents calculated solutions to problems in fundamental and applied electrochemistry. It uses industrial data to illustrate scientific concepts and scientific knowledge to solve practical problems. It is subdivided into three parts. The first uses modern basic concepts, the second studies the scientific basis for electrode and electrolyte thermodynamics (including E-pH diagrams and the minimum energy involved in transformations) and the kinetics of rate processes (including the energy lost in heat and in parasite reactions). The third part treats larger problems in electrolysis and power generation, as well as in corrosion and its prevention. Each chapter includes three sections: the presentation of useful principles; some twenty problems with their solutions; and, a set of unsolved problems

POWERPLAY: Training an Increasingly General Problem Solver by Continually Searching for the Simplest Still Unsolvable Problem

Directory of Open Access Journals (Sweden)

Jürgen eSchmidhuber

2013-06-01

Full Text Available Most of computer science focuses on automatically solving given computational problems. I focus on automatically inventing or discovering problems in a way inspired by the playful behavior of animals and humans, to train a more and more general problem solver from scratch in an unsupervised fashion. Consider the infinite set of all computable descriptions of tasks with possibly computable solutions. The novel algorithmic framework POWERPLAY (2011 continually searches the space of possible pairs of new tasks and modifications of the current problem solver, until it finds a more powerful problem solver that provably solves all previously learned tasks plus the new one, while the unmodified predecessor does not. Wow-effects are achieved by continually making previously learned skills more efficient such that they require less time and space. New skills may (partially re-use previously learned skills. POWERPLAY's search orders candidate pairs of tasks and solver modifications by their conditional computational (time & space complexity, given the stored experience so far. The new task and its corresponding task-solving skill are those first found and validated. The computational costs of validating new tasks need not grow with task repertoire size. POWERPLAY's ongoing search for novelty keeps breaking the generalization abilities of its present solver. This is related to Goedel's sequence of increasingly powerful formal theories based on adding formerly unprovable statements to the axioms without affecting previously provable theorems. The continually increasing repertoire of problem solving procedures can be exploited by a parallel search for solutions to additional externally posed tasks. POWERPLAY may be viewed as a greedy but practical implementation of basic principles of creativity. A first experimental analysis can be found in separate papers [58, 56, 57].

Solved and unsolved problems in boiler systems. Learning from accidents

International Nuclear Information System (INIS)

Ozawa, Mamoru

2000-01-01

This paper begins with a brief review on the similarity law of conventional fossil-fuel-fired boilers. The concept is based on the fact that the heat release due to combustion in the furnace is restricted by the furnace volume but the heat absorption is restricted by the heat transfer surface area. This means that a small-capacity boiler has relatively high specific furnace heat release rate, about 10 MW/m 3 , and on the contrary a large-capacity boiler has lower value. The surface-heat-flux limit is mainly dominated by the CHF inside the water-wall tubes of the boiler furnace, about 350 kW/m 2 . This heat-flux limit is almost the same order independently on the capacity of boilers. For the safety of water-walls, it is essential to retain suitable water circulation, i.e. circulation ratio and velocity of water. This principle is a common knowledge of boiler designer, but actual situation is not the case. Newly designed boilers often suffer from similar accidents, especially burnout due to circulation problems. This paper demonstrates recent accidents encountered in practical boilers, and raises problems of rather classical but important two-phase flow and heat transfer. (author)

Evaluation by the Department de Surete Nucleaire of unsolved PWR safety problems

International Nuclear Information System (INIS)

Dupuis, M.C.; Cayol, A.; Fourest, B.

1980-04-01

The deterministic or probabilistic methods of safety analysis and the analysis of accidents used at the design and construction stage have enabled certain safety problems connected with the PWR programme in France to be identified. Some of these problems have already been stressed by the NRC whereas others are specific to the safety approach practised in France. These problems have led to the adoption of special measurements on the reactors already in operation and should be accounted for in the design of future installations. Analysis of running experience and of incidents should be used to check the validity of the steps taken at the design stage and to identify the weak points of the facilities, especially in their piloting and at the man-machine interface [fr

Some problems of physics of ultrahigh energy cosmic rays

International Nuclear Information System (INIS)

Isaev, P.S.

1999-01-01

Nearest 15-20 years will be years of flourishing of experimental researches into the energy of cosmic rays at > or ∼ 10 15 eV and of new discoveries in the physics of elementary particles of ultrahigh energies. Unsolved problems of modern physics of ultrahigh energy cosmic rays, which are relevant to the problems of elementary particles physics, are reviewed

PowerPlay: Training an Increasingly General Problem Solver by Continually Searching for the Simplest Still Unsolvable Problem.

Science.gov (United States)

Schmidhuber, Jürgen

2013-01-01

Most of computer science focuses on automatically solving given computational problems. I focus on automatically inventing or discovering problems in a way inspired by the playful behavior of animals and humans, to train a more and more general problem solver from scratch in an unsupervised fashion. Consider the infinite set of all computable descriptions of tasks with possibly computable solutions. Given a general problem-solving architecture, at any given time, the novel algorithmic framework PowerPlay (Schmidhuber, 2011) searches the space of possible pairs of new tasks and modifications of the current problem solver, until it finds a more powerful problem solver that provably solves all previously learned tasks plus the new one, while the unmodified predecessor does not. Newly invented tasks may require to achieve a wow-effect by making previously learned skills more efficient such that they require less time and space. New skills may (partially) re-use previously learned skills. The greedy search of typical PowerPlay variants uses time-optimal program search to order candidate pairs of tasks and solver modifications by their conditional computational (time and space) complexity, given the stored experience so far. The new task and its corresponding task-solving skill are those first found and validated. This biases the search toward pairs that can be described compactly and validated quickly. The computational costs of validating new tasks need not grow with task repertoire size. Standard problem solver architectures of personal computers or neural networks tend to generalize by solving numerous tasks outside the self-invented training set; PowerPlay's ongoing search for novelty keeps breaking the generalization abilities of its present solver. This is related to Gödel's sequence of increasingly powerful formal theories based on adding formerly unprovable statements to the axioms without affecting previously provable theorems. The continually increasing

Colloquium spectroscopicum internationale XXIV: From big bang to unsolved problems

International Nuclear Information System (INIS)

Schrader, B.

1985-01-01

Brief report on the Colloquium Spectroscopicum Internationale 1985, held in Garmisch-Partenkirchen (FRG). The opening lecture, ''From Big Bang to Black Holes'', unfolded the current knowledge of the universe, whereas two thirds of the following 61 plenary lectures dealt with problems of atomic spectroscopy and the remaining papers with molecular spectroscopy. In 40 poster sessions 350 posters were briefly discussed, and the conference was accompanied by an exhibition of latest spectrometric equipment. Experimental methods were the centre of discussions of atomic spectroscopy experts, whereas in the field of moclecular spectroscopy issues such as standards for digitised spectra, databases and information exchange via data networks met with great interest. (RB) [de

Poverty – a major economical problem

Directory of Open Access Journals (Sweden)

Assistent Professor Somogyi János

2008-05-01

Full Text Available Poverty is the state for the majority of the world’s people and nations. Yet there is plenty offood in the world for everyone. The problem is that hungry people are trapped in severe poverty. They lackthe money to buy enough food to nourish them. Being constantly malnourished, they become weaker and oftensick. This makes them increasingly less able to work, which then makes them even poorer and hungrier.This downward spiral often continues until death for them and their families.Why is this? How is to blame? Poor people for their own predicament? Have they been lazy, madepoor decisions, and been solely responsible for their plight? What about their governments? Have theypursued policies that actually harm successful development? Such causes of poverty and inequality are nodoubt real. But deeper and more global causes of poverty are often less discussed. This article explores variouspoverty problems in more depth.

The Influence of Open Goals on the Acquisition of Problem-Relevant Information

Science.gov (United States)

Moss, Jarrod; Kotovsky, Kenneth; Cagan, Jonathan

2007-01-01

There have been a number of recent findings indicating that unsolved problems, or open goals more generally, influence cognition even when the current task has no relation to the task in which the goal was originally set. It was hypothesized that open goals would influence what information entered the problem-solving process. Three studies were…

Current problems of Bulgarian nuclear power

International Nuclear Information System (INIS)

Luk'yanov, A.A.; Vapirev, E.I.

1996-01-01

The main unsolved problems of Bulgarian nuclear power industry now are: a serious trouble that the WWER-440 units will have to be phased out before the end of their projected life since they do not meet contemporary safety requirements; heavy economic difficulties with the construction of the new NPP 'Belene'; accumulation of a considerable amount of spent fuel because of its interrupted export to Russia

Revisiting the Majority Problem: Average-Case Analysis with Arbitrarily Many Colours

OpenAIRE

Kleerekoper, Anthony

2016-01-01

The majority problem is a special case of the heavy hitters problem. Given a collection of coloured balls, the task is to identify the majority colour or state that no such colour exists. Whilst the special case of two-colours has been well studied, the average-case performance for arbitrarily many colours has not. In this paper, we present heuristic analysis of the average-case performance of three deterministic algorithms that appear in the literature. We empirically validate our analysis w...

Unsolved problems in applying U.S. regulatory guides to control system equipment

International Nuclear Information System (INIS)

Stade, R.E.

1978-01-01

Two current problems encountered when designing control systems to the United States Regulatory Guide requirements are discussed. They are: 1) Level of surge voltages that should be specified when procuring solid state control and instrumentation systems and equipment. 2) The approach to be used qualifying equipment that must meet the aging requirements. (author)

Interpersonal problems, dependency, and self-criticism in major depressive disorder.

Science.gov (United States)

Dinger, Ulrike; Barrett, Marna S; Zimmermann, Johannes; Schauenburg, Henning; Wright, Aidan G C; Renner, Fritz; Zilcha-Mano, Sigal; Barber, Jacques P

2015-01-01

The goal of the present research was the examination of overlap between 2 research traditions on interpersonal personality traits in major depression. We hypothesized that Blatt's (2004) dimensions of depressive experiences around the dimensions of relatedness (i.e., dependency) and self-definition (i.e., self-criticism) are associated with specific interpersonal problems according to the interpersonal circumplex model (Leary, 1957). In addition, we examined correlations of interpersonal characteristics with depression severity. Analyses were conducted on 283 patients with major depressive disorder combined from 2 samples. Of the patients, 151 participated in a randomized controlled trial in the United States, and 132 patients were recruited in an inpatient unit in Germany. Patients completed measures of symptomatic distress, interpersonal problems, and depressive experiences. Dependency was associated with more interpersonal problems related to low dominance and high affiliation, while self-criticism was associated with more interpersonal problems related to low affiliation. These associations were independent of depression severity. Self-criticism showed high overlap with cognitive symptoms of depression. The findings support the interpersonal nature of Blatt's dimensions of depressive experiences. Self-criticism is associated with being too distant or cold toward others as well as greater depression severity, but is not related to the dimension of dominance. © 2014 Wiley Periodicals, Inc.

Phytoextraction crop disposal--an unsolved problem

International Nuclear Information System (INIS)

Sas-Nowosielska, A.; Kucharski, R.; Malkowski, E.; Pogrzeba, M.; Kuperberg, J.M.; Krynski, K.

2004-01-01

Several methods of contaminated crop disposal after phytoextraction process (composting, compaction, incineration, ashing, pyrolysis, direct disposal, liquid extraction) have been described. Advantages and disadvantages of methods are presented and discussed. Composting, compaction and pyrolysis are the pretreatment steps, since significant amount of contaminated biomass will still exist after each of the process. Four methods of final disposal were distinguished: incineration, direct disposal, ashing and liquid extraction. Among them, incineration (smelting) is proposed as the most feasible, economically acceptable and environmentally sound. - Methods of contaminated crop disposal are described and evaluated

Application of evolutionary algorithm methods to polypeptide folding: comparison with experimental results for unsolvated Ac-(Ala-Gly-Gly)5-LysH+

DEFF Research Database (Denmark)

Damsbo, Martin; Kinnear, Brian S; Hartings, Matthew R

2004-01-01

We present an evolutionary method for finding the low-energy conformations of polypeptides. The application, called FOLDAWAY,is based on a generic framework and uses several evolutionary operators as well as local optimization to navigate the complex energy landscape of polypeptides. It maintains...... mobility measurements. It has a flat energy landscape where helical and globular conformations have similar energies. FOLDAWAY locates several large groups of structures not found in previous molecular dynamics simulations for this peptide, including compact globular conformations, which are probably...... two complementary representations of the structures and uses the CHARMM force field for evaluating the energies. The method is applied to unsolvated Met-enkephalin and Ac-(Ala-Gly-Gly)(5)-Lys(+)H(+). Unsolvated Ac-(Ala-Gly-Gly)(5)-Lys(+)H(+) has been the object of recent experimental studies using ion...

Fluorodeoxyglucose positron emission tomography in pancreatic cancer: an unsolved problem

International Nuclear Information System (INIS)

Kato, Takashi; Fukatsu, Hiroshi; Ito, Kengo; Tadokoro, Masanori; Ota, Toyohiro; Ikeda, Mitsuru; Isomura, Takayuki; Ito, Shigeki; Nishino, Masanari; Ishigaki, Takeo

1995-01-01

The aim of this study was to examine the significance and problems of 2-[fluorine-18]-2-deoxy-d-glucose (FDG) positron emission tomography (PET) in diagnosing pancreatic cancer and mass-forming pancreatitis (MFP). PET, X-ray computed tomography (CT) and magnetic resonance (MR) imaging were performed in 15 patients with pancreatic cancer and nine patients with MFP. The areas of the PET scan were determined according to the markers drawn on the patients at CT or MR imaging. Regions of interests (ROIs) were placed by reference to the CT or MR images corresponding to the PET images. Tissue metabolism was evaluated by the differential absorption ratio (DAR) at 50 min after intravenous injection of FDG [DAR = tissue tracer concentration/(injected dose/body weight). The DAR value differed significantly in pancreatic cancer (mean±SD, 4.64±1.94) and MFP (mean±SD, 2.84±2.22) (P<0.05). In one false-negative case (mucinous adenocarcinoma), the tumour contained a small number of malignant cells. In one false-positive case, lymphocytes accumulated densely in the mass in the pancreatic head. Further studies are necessary to investigate the histopathological characteristics (especially the cellularity) and other factors affecting the FDG DAR on PET images. (orig.)

Hydrocarbon Development from Shale: A Set of Important, Unsolved Problems

Science.gov (United States)

Ingraffea, A. R.; Burchell, A.; Howarth, R.; Wilson, A.; Doe, P.; Colborn, T.; Wood, M. C.

2013-12-01

Hydraulic fracturing has become synonymous with the new technologies and processes used to develop oil and methane from shale formations. We will address the following important set of problems associated with such development and the role scientists are playing in communicating these to the public. Human Health Consequences: The health consequences of the wide-range of fugitive hydrocarbon emissions associated with methane and oil are not adequately addressed. New evidence about exposure to, and the known and possible health effects of, these toxic hitch hikers will be presented. Methane Emissions: Methane is a more powerful greenhouse gas than carbon dioxide, though atmospheric residence is shorter. Methane is emitted through-out the development life-cycle, albeit there is uncertainty over the rate, and short-term effect on global warming. Leakage from Faulty Wells: Multiple industry studies show that about 5 percent of oil and gas wells immediately leak methane and other fluids into the atmosphere and water wells due to integrity issues and increasing rates of leakage over time. With millions of wells drilled worldwide, and millions more expected, this problem is neither negligible nor preventable with current technology. Federal Exemptions and Home Rule: 'Fracking' currently slips through federal environmental statutory law because of an industry-friendly exemption. However, trusts are established in US law and the Public Trust Doctrine provides a basis for courts to enjoin 'fracking' due to the potential impact on beneficiaries of the trust --present and future generations. The public trust designates government as a trustee of crucial resources and imposes a fiduciary obligation on agencies to prevent "substantial impairment" of- and protect access to- clean air, clean water and other natural resources vital for public welfare and survival. Already applied to the realm of ecology, the doctrine is reviewed as a legal and policy toot to protect communities

Major unsolved points in adult neurogenesis: doors open on a translational future?

Directory of Open Access Journals (Sweden)

Paolo ePeretto

2014-06-01

Full Text Available The ultimate goal of exploiting adult neurogenesis (AN as a source of cell replacement is far from being achieved. In spite of many data gathered during the last two decades on homeostatic and reactive neurogenesis, it is evident that such knowledge is not sufficient for granting translational outcomes. By asking the question whether AN research field has to be considered as a dead end in such a perspective, here we review some major unresolved issues: multifaceted evolutionary constraints emerged in mammals, stem/progenitor cell type/availability and tissue permissivity, the possible impact on other brain functions and/or interplay with other forms of plasticity, and relevance in humans. We suggest that full understanding of AN biological processes is an essential step to their possible exploitation for brain repair, and that further fundamental, multidisciplinary research is required before translational outcomes can be reached. Scientist's attitude and their communication skills are also important. To avoid overestimation of AN reparative potential, more distant goals of cell replacement should be kept clearly distinct from restorative approaches involving AN plasticity, both representing translational perspectives.

Topological Galois theory solvability and unsolvability of equations in finite terms

CERN Document Server

Khovanskii, Askold

2014-01-01

This book provides a detailed and largely self-contained description of various classical and new results on solvability and unsolvability of equations in explicit form. In particular, it offers a complete exposition of the relatively new area of topological Galois theory, initiated by the author. Applications of Galois theory to solvability of algebraic equations by radicals, basics of Picard–Vessiot theory, and Liouville's results on the class of functions representable by quadratures are also discussed. A unique feature of this book is that recent results are presented in the same elementary manner as classical Galois theory, which will make the book useful and interesting to readers with varied backgrounds in mathematics, from undergraduate students to researchers. In this English-language edition, extra material has been added (Appendices A–D), the last two of which were written jointly with Yura Burda.

Chemical physics of decomposition of energetic materials. Problems and prospects

International Nuclear Information System (INIS)

Smirnov, Lev P

2004-01-01

The review is concerned with analysis of the results obtained in the kinetic and mechanistic studies on decomposition of energetic materials (explosives, powders and solid propellants). It is shown that the state-of-the art in this field is inadequate to the potential of modern chemical kinetics and chemical physics. Unsolved problems are outlined and ways of their solution are proposed.

Assessment on major livestock health problems in southern zone of ...

African Journals Online (AJOL)

A cross sectional study was conducted to identify the major livestock health problems in southern zone of Tigray, northern Ethiopia from July 2014 to June 2016. Questionnaire survey and case observational study were employed for data collection. A total of 120 respondents were interviewed for the questionnaire survey.

Fractures on curved surfaces: A classic problem solved

Science.gov (United States)

Balcerak, Ernie

2011-11-01

Sheeting joints—large fractures parallel to a curved rock surface—are common in many locations on Earth, such as the iconic Half Dome in Yosemite National Park in California. Explaining how these fractures form has been a classic unsolved problem in geology. Martel solved the problem by reformulating the static equilibrium equations in a curvilinear reference frame. His analysis shows that compression along a curved surface can induce tension perpendicular to the surface, which can cause subsurface cracks to open. He found that the curvature of a rock surface plays a key role in the formation of fractures.

Problems for the seminar, ICTP, 2007-2008

International Nuclear Information System (INIS)

Arnold, V.

2008-01-01

The following problems for the ICPT seminar 2007-2008 are specified: topological classification of polynomials; equipartition of indivisible integer vectors; geometrical progressions? fractional parts? equipartitions; statistics of continued fractions of eigenvalues of matrices; growth rate of elements of periodic continued fractions; periods of geometrical progressions of residues; Kolmogorov?s distributions; stochasticity degree of arithmetical progressions of fractional parts; is a generic geometrical progression of fractional parts random?; prime numbers distribution?s randomness; algorithmic unsolvability of problems of higher dimensional continued fractions; periods of continued fractions of roots of quadratic equations; statistics of lengths of periods of continued fractions of quadratic irrational numbers; random matrices? characteristic polynomials distributions

NATO Advanced Research Workshop on Earth Rotation : Solved and Unsolved Problems

CERN Document Server

1986-01-01

The idea for organl.zl.ng an Advanced Research Workshop entirely devoted to the Earth rotation was born in 1983 when Professor Raymond Hide suggested this topic to the special NATO panel of global transport mechanism in the Geosciences. Such a specialized meeting did not take place since the GEOP research conference on the rotation of the Earth and polar motion which was held at the Ohio State University (USA) in 1973. In the last ten years, highly precise measurements of the Earth's rotation parameters and new global geophysical data have become available allowing major advance to be made in the under­ standing of the various irregularities affecting the Earth's rotation. The aim of the workshop was to bring together scientists who have made important contributions in this field during the last decade both at the observational and geophysical interpretation levels. The confe­ rence was divided into four main topics. The first session was dedicated to the definition, implementation and maintenance of the te...

Boundary Judgments in Water Governance: Diagnosing Internal and External Factors that Matter in a Complex World

NARCIS (Netherlands)

de Loë, Rob C.; Patterson, J.J.

2018-01-01

Governance failures are widely recognized as a key reason why, despite sustained attention over previous decades, many longstanding water problems continue to go unsolved around the world. A major challenge in analyzing and addressing water governance problems is making “boundary judgments” in the

Lipid polymorphism and the functional roles of lipids in biological membranes

NARCIS (Netherlands)

Cullis, P.R.; Kruijff, B. de

1979-01-01

The reasons for the great variety of lipids found in biological membranes, and the relations between lipid composition and membrane function pose major unsolved problems in membrane biology. Perhaps the only major functional role of lipids which may be regarded as firmly established involves the

Image Processing: Some Challenging Problems

Science.gov (United States)

Huang, T. S.; Aizawa, K.

1993-11-01

Image processing can be broadly defined as the manipulation of signals which are inherently multidimensional. The most common such signals are photographs and video sequences. The goals of processing or manipulation can be (i) compression for storage or transmission; (ii) enhancement or restoration; (iii) analysis, recognition, and understanding; or (iv) visualization for human observers. The use of image processing techniques has become almost ubiquitous; they find applications in such diverse areas as astronomy, archaeology, medicine, video communication, and electronic games. Nonetheless, many important problems in image processing remain unsolved. It is the goal of this paper to discuss some of these challenging problems. In Section I, we mention a number of outstanding problems. Then, in the remainder of this paper, we concentrate on one of them: very-low-bit-rate video compression. This is chosen because it involves almost all aspects of image processing.

Problems in practical radiation education

Energy Technology Data Exchange (ETDEWEB)

Turuoka, Moriaki [Hokkaido Sapporo Kaisei Senior High School, Sapporo, Hokkaido (Japan)

1999-09-01

Based on the results of questionnaire survey carried out in 1995 and 1997 and addressed to the same students in a senior high school, Japan, the author arrived at a conclusion that the students had the chance to get information on radiation from the mass media other than at school during two school year. At school they learn through a textbook and also complementary educational materials the teachers provide which will help understanding and improving the interests in radiations. In the practice, some important problems remain unsolved: the student's feeling toward radiations as risky, inadequate descriptions on radiations found in the textbook, and the difficulties in obtaining teaching materials for experiments. These problems must be resolved first of all for the solution of our future energy supply. (S. Ohno)

Some human-related problems in radiation protection

International Nuclear Information System (INIS)

Yoshizawa, Yasuo

1980-01-01

Radiation protection includes both human and source-related problems. The human problems have not only medical but also social aspects, such as labor management. Special attention should be paid to the fact that the subject of radiation protection is not a human being as living thing but as member of society. ICRP recommended that conditions of work can be divided into two classed, working condition A and B, according to annual exposure. This application is of great value to radiation protection practice. Nevertheless the legal regulations do not adopt it yet. The present condition of the medical surveillance of radiation workers is not appropriate from the scientific standpoint. This is the difficult problem which is caused by the delay of the legal application of ICRP recommendation. Compensation for occupational radiation hazards should be overlooked. This problem have been investigated by an authorized committee, but a number of unsolved problems still remain. (author)

An overview of major aspects of the aircraft impact problem

International Nuclear Information System (INIS)

Kamil, H.; Kost, G.; Sharpe, R.

1978-01-01

The major aspects of the aircraft impact problem are identified and the most relevant topics for future investigations are discussed. The emphasis is on three main topics: modeling techniques, influence of non-linear behavior, and importance of damping in the dynamic structural response analyses for aircraft loading. Results are presented from brief studies involving response of linear and nonlinear simple systems to short-duration impulsive loadings of the aircraft impact type. (Auth.)

Major Gravitational Phenomena Explained by the Micro-Quanta Paradigm

Directory of Open Access Journals (Sweden)

Michelini M.

2010-01-01

Full Text Available Some major problems of physics, which remained unsolved within classical and rel- ativistic gravitation theories, are explained adopting the quantum gravity interaction descending from the micro-quanta paradigm. The energy source of the gravitational power P g r , which heats and contracts the Bok’s gas globules harbouring the future stars, is identified and defined as well as the gravitational power generated on the solid / fluid planets. Calculations are carried out to make the comparison between P g r predicted for the solar giant planets and the measured infrared radiation power P int coming from the interior. The case of planets with solid crust (Earth, etc. requires a particular attention due to the threat to stability produced by the thermal dilatation. An analysis is done of the Earth’s planetary equilibrium which may be attained eliminating the temperature rise through the migration of hot internal magma across the crust fractured by earth- quakes. The temperatures observed up to 420,000 years ago in Antartica through Vostok and Epica ice cores suggest the possibility that the Earth gravitational power P g r may be radiated in space through these temperature cycles (Glacial Eras. In this general frame the Earth’s high seismicity and the dynamics of Plate tectonics may find their origin.

Major Gravitational Phenomena Explained by the Micro-Quanta Paradigm

Directory of Open Access Journals (Sweden)

Michelini M.

2010-01-01

Full Text Available Some major problems of physics, which remained unsolved within classical and relativistic gravitation theories, are explained adopting the quantum gravity interaction descending from the micro-quanta paradigm. The energy source of the gravitational power $P_{gr}$, which heats and contracts the Bok's gas globules harbouring the future stars, is identified and defined as well as the gravitational power generated on the solid/fluid planets. Calculations are carried out to make the comparison between $P_{gr}$ predicted for the solar giant planets and the measured infrared radiation power $P_{int}$ coming from the interior. The case of planets with solid crust (Earth, etc. requires a particular attention due to the threat to stability produced by the thermal dilatation. An analysis is done of the Earth's planetary equilibrium which may be attained eliminating the temperature rise through the migration of hot internal magma across the crust fractured by earthquakes. The temperatures observed up to 420,000 years ago in Antartica through Vostok and Epica ice cores suggest the possibility that the Earth gravitational power $P_{gr}$ may be radiated in space through these temperature cycles (Glacial Eras. In this general frame the Earth's high seismicity and the dynamics of Plate tectonics may find their origin.

Bayesian inference of the metazoan phylogeny

DEFF Research Database (Denmark)

Glenner, Henrik; Hansen, Anders J; Sørensen, Martin V

2004-01-01

Metazoan phylogeny remains one of evolutionary biology's major unsolved problems. Molecular and morphological data, as well as different analytical approaches, have produced highly conflicting results due to homoplasy resulting from more than 570 million years of evolution. To date, parsimony has...

Kleinian groups and uniformization in examples and problems

CERN Document Server

Krushkal′, S L

1986-01-01

Aimed at researchers, graduate students and undergraduates alike, this book presents a unified exposition of all the main areas and methods of the theory of Kleinian groups and the theory of uniformization of manifolds. The past 20 years have seen a rejuvenation of the field, due to the development of powerful new methods in topology, the theory of functions of several complex variables, and the theory of quasiconformal mappings. Thus this new book should provide a valuable resource, listing the basic facts regarding Kleinian groups and serving as a general guide to the primary literature, particularly the Russian literature in the field. In addition, the book includes a large number of examples, problems, and unsolved problems, many of them presented for the first time.

Aeroelastic instability problems for wind turbines

DEFF Research Database (Denmark)

Hansen, Morten Hartvig

2007-01-01

This paper deals with the aeroelostic instabilities that have occurred and may still occur for modem commercial wind turbines: stall-induced vibrations for stall-turbines, and classical flutter for pitch-regulated turbines. A review of previous works is combined with derivations of analytical...... stiffness and chordwise position of the center of gravity along the blades are the main parameters for flutter. These instability characteristics are exemplified by aeroelastic stability analyses of different wind turbines. The review of each aeroelastic instability ends with a list of current research...... issues that represent unsolved aeroelostic instability problems for wind turbines. Copyright (c) 2007 John Wiley & Sons, Ltd....

Social Problems in the Russian Army within the Framework of Social Work

Directory of Open Access Journals (Sweden)

Irina Surkova

2015-03-01

Full Text Available This article aims at describing social problems we find in the Russian Army. The research has allowed us to get a ranging of servicemen`s social problems: housing, material maintenance and hard-earned money, realization of social guarantees, life conditions and problem of relationships within families, time-limit, the regulation of life, restricting the freedom, humiliating treatment of juniors and bullying. Unsolved social problems of servicemen may also cause that people who are going to protect the country from danger, may become threats themselves. The Russian army consumes a great amount of resources. Recently mass media has put these issues on the public agenda. Focus in article is also to give a picture of how social workers work to solve social problems in the Russian Army.

Heterogeneous quantum computing for satellite constellation optimization: solving the weighted k-clique problem

Science.gov (United States)

Bass, Gideon; Tomlin, Casey; Kumar, Vaibhaw; Rihaczek, Pete; Dulny, Joseph, III

2018-04-01

NP-hard optimization problems scale very rapidly with problem size, becoming unsolvable with brute force methods, even with supercomputing resources. Typically, such problems have been approximated with heuristics. However, these methods still take a long time and are not guaranteed to find an optimal solution. Quantum computing offers the possibility of producing significant speed-up and improved solution quality. Current quantum annealing (QA) devices are designed to solve difficult optimization problems, but they are limited by hardware size and qubit connectivity restrictions. We present a novel heterogeneous computing stack that combines QA and classical machine learning, allowing the use of QA on problems larger than the hardware limits of the quantum device. These results represent experiments on a real-world problem represented by the weighted k-clique problem. Through this experiment, we provide insight into the state of quantum machine learning.

Solved and unsolved problems in relativistic quantum chemistry

International Nuclear Information System (INIS)

Kutzelnigg, Werner

2012-01-01

Graphical abstract: The graphical abstract represents the Dirac-Coulomb Hamiltonian in Fock space in a diagrammatic notation. A line (vertical or slanted) with an upgoing arrow represents an eletron, with a downgoing arrow a positron. A cross in the first line means the potential created by a nucleus, a broken line represents the Coulomb interaction between electrons and positrons. Highlights: ► Relativistic many-electron theory needs a Fock space and a field-dependent vacuum. ► A good starting point is QED in Coulomb gauge without transversal photons. ► The Dirac underworld picture is obsolete. ► A kinetically balanced even-tempered Gaussian basis is complete. ► ‘Quantum chemistry in Fock space is preferable over QED. - Abstract: A hierarchy of approximations in relativistic many-electron theory is discussed that starts with the Dirac equation and its expansion in a kinetically balanced basis, via a formulation of non-interacting electrons in Fock space (which is the only consistent way to deal with negative-energy states). The most straightforward approximate Hamiltonian for interacting electrons is derived from quantum electrodynamics (QED) in Coulomb gauge with the neglect of transversal photons. This allows an exact (non-perturbative) decoupling of the electromagnetic field from the fermionic field. The electric interaction of the fermions is non-retarded and non-quantized. The quantization of the fermionic field leads to a polarizable vacuum. The simplest (but somewhat problematic) approximation is a no-pair projected theory with external-field projectors. The Dirac-Coulomb operator in configuration space (first quantization) is not acceptable, even if the Brown–Ravenhall disease is much less virulent than often claimed. Effects of transversal photons, such as the Breit interaction and renormalized self-interaction can be taken care of perturbatively at the end, but there are still many open questions.

Social problems and territorial experiences from closing down Tihange NPP

International Nuclear Information System (INIS)

Lizin, A.M.

2000-01-01

The town of Huy, better known by the name of the NPP Tihange, which is the nearby village, accounts to 50,000 inhabitants including the surrounding region. An Advisory Committee at a community level was set up concerned with the emergency services and the NPP related problems. One of the outstanding problems is the planned interim storage for radioactive waste. The unsolved question of long term storage in Belgium resulted in the fact that general situation is not promising for launching the debate on the future of nuclear energy. The mission of the delegation from Huy visited Tokaimura with the aim to measure the scale of real responsibilities and the concern against nuclear power that the accident created in the population

Domestic Violence against Women – An Unsolved Issue: A Community Based Study in an Urban Slum of Kolkata, India

Directory of Open Access Journals (Sweden)

Jayita Pal

2017-10-01

Full Text Available Introduction: Domestic Violence against women is still an unsolved issue in India, though, it is an important public health problem contributing to physical, mental illness and low quality of life. Aim: The study was undertaken with the aim to estimate the prevalence of domestic violence against ever married women in an urban slum and the associated factors contributing to it. Materials and Methods: A community-based cross-sectional study had been conducted among 430 ever married women of reproductive age group, selected using a systematic random sampling technique in an urban slum of Kolkata. Interviews were conducted using pre-designed, pre-tested semi structured schedule regarding their socio-demographic characteristics, violence experienced by the subjects in their lifetime, type of violence (physical, emotional and sexual violence and the person responsible for the same. Data were entered and analysed using SPSS 20.0 version. Results: The overall prevalence of any form of violence in the study population as a whole was (59.3%. The prevalence of physical, emotional, sexual violence was 61.6%, 84.3%and 58.8%, respectively. The occurrence of the event was reported by only 33.1% of the victims. Multivariate analysis revealed violence was higher among women belonging to families with low per capita income (6 years, low educational background of husband, not able to bear a male child, unemployment amongst both the spouses, leave the household on any pretext without prior permission from husband and where the wives did not attend household activities properly. Conclusion: The prevalence of domestic violence in urban slum of Kolkata was high which is an alarming public health problem which needs to be addressed at the earliest through awareness programmes and empowerment of women.

Statistical processing of experimental data

OpenAIRE

NAVRÁTIL, Pavel

2012-01-01

This thesis contains theory of probability and statistical sets. Solved and unsolved problems of probability, random variable and distributions random variable, random vector, statistical sets, regression and correlation analysis. Unsolved problems contains solutions.

Comparing On-Campus and Distance Education assessment in the form of Project Organized Problem Based Learning (POPBL)

DEFF Research Database (Denmark)

Helbo, Jan; Borch, Ole

2006-01-01

This paper describes the first experiences in on-line assessment in the POPBL distance education: Master of Industrial Information technology (MII) at Aalborg University, Denmark (AAU). The accomplished assessment of some projects and some courses has been changed from a normal on-campus seminar...... activity to an on-line event. The modifications in roles for teacher, censor and student are reported and some recommendations and unsolved problems are identified....

Manual Removal of the Placenta after Vaginal Delivery: An Unsolved Problem in Obstetrics

Science.gov (United States)

Zimmermann, Roland

2014-01-01

The third stage of labor is associated with considerable maternal morbidity and mortality. The major complication is postpartum hemorrhage (PPH), which is the leading cause of maternal morbidity and mortality worldwide. Whereas in the event of PPH due to atony of the uterus there exist numerous treatment guidelines; for the management of retained placenta the general consensus is more difficult to establish. Active management of the third stage of labour is generally accepted as standard of care as already its duration is contributing to the risk of PPH. Despite scant evidence it is commonly advised that if the placenta has not been expelled 30 minutes after delivery, manual removal of the placenta should be carried out under anaesthesia. Pathologic adhesion of the placenta in the low risk situation usually is diagnosed at the time of delivery; therefore a pre- or intrapartum screening opportunity for placenta accreta would be desirable. But diagnosis of abnormalities of placentation other than placenta previa remains a challenge. Nevertheless the use of ultrasound and doppler sonography might be helpful in the third stage of labor. An improvement might be the implementation of standardized operating procedures for retained placenta which could contribute to a reduction of maternal morbidity. PMID:24812585

Dosimetry Control: Technic and methods. Proceedings of the international workshop 'Actual problems of dosimetry'

International Nuclear Information System (INIS)

Lyutsko, A.M.; Nesterenko, V.B.; Chudakov, V.A.; Konoplya, E.F.; Milyutin, A.A.

1997-10-01

There is a number of unsolved problems of both dosimetric and radiometric control, questions of the biological dosimetry, reconstruction of dozes of irradiation of the population at radiation incidents, which require coordination of efforts of scientists in various areas of a science. The submitted materials are grouped on five units: dosimetry engineering, biological dosimetry and markers of radiation impact, dosimetry of a medical irradiation, normative and measurement assurance of the dosimetric control, monitoring and reconstruction of dozes at radiation incidents

Using Stochastic Spiking Neural Networks on SpiNNaker to Solve Constraint Satisfaction Problems

Directory of Open Access Journals (Sweden)

Gabriel A. Fonseca Guerra

2017-12-01

Full Text Available Constraint satisfaction problems (CSP are at the core of numerous scientific and technological applications. However, CSPs belong to the NP-complete complexity class, for which the existence (or not of efficient algorithms remains a major unsolved question in computational complexity theory. In the face of this fundamental difficulty heuristics and approximation methods are used to approach instances of NP (e.g., decision and hard optimization problems. The human brain efficiently handles CSPs both in perception and behavior using spiking neural networks (SNNs, and recent studies have demonstrated that the noise embedded within an SNN can be used as a computational resource to solve CSPs. Here, we provide a software framework for the implementation of such noisy neural solvers on the SpiNNaker massively parallel neuromorphic hardware, further demonstrating their potential to implement a stochastic search that solves instances of P and NP problems expressed as CSPs. This facilitates the exploration of new optimization strategies and the understanding of the computational abilities of SNNs. We demonstrate the basic principles of the framework by solving difficult instances of the Sudoku puzzle and of the map color problem, and explore its application to spin glasses. The solver works as a stochastic dynamical system, which is attracted by the configuration that solves the CSP. The noise allows an optimal exploration of the space of configurations, looking for the satisfiability of all the constraints; if applied discontinuously, it can also force the system to leap to a new random configuration effectively causing a restart.

Using Stochastic Spiking Neural Networks on SpiNNaker to Solve Constraint Satisfaction Problems.

Science.gov (United States)

Fonseca Guerra, Gabriel A; Furber, Steve B

2017-01-01

Constraint satisfaction problems (CSP) are at the core of numerous scientific and technological applications. However, CSPs belong to the NP-complete complexity class, for which the existence (or not) of efficient algorithms remains a major unsolved question in computational complexity theory. In the face of this fundamental difficulty heuristics and approximation methods are used to approach instances of NP (e.g., decision and hard optimization problems). The human brain efficiently handles CSPs both in perception and behavior using spiking neural networks (SNNs), and recent studies have demonstrated that the noise embedded within an SNN can be used as a computational resource to solve CSPs. Here, we provide a software framework for the implementation of such noisy neural solvers on the SpiNNaker massively parallel neuromorphic hardware, further demonstrating their potential to implement a stochastic search that solves instances of P and NP problems expressed as CSPs. This facilitates the exploration of new optimization strategies and the understanding of the computational abilities of SNNs. We demonstrate the basic principles of the framework by solving difficult instances of the Sudoku puzzle and of the map color problem, and explore its application to spin glasses. The solver works as a stochastic dynamical system, which is attracted by the configuration that solves the CSP. The noise allows an optimal exploration of the space of configurations, looking for the satisfiability of all the constraints; if applied discontinuously, it can also force the system to leap to a new random configuration effectively causing a restart.

Influence of Parental and Grandparental Major Depressive Disorder on Behavior Problems in Early Childhood: A Three-Generation Study

Science.gov (United States)

Olino, Thomas M.; Pettit, Jeremy W.; Klein, Daniel N.; Allen, Nicholas B.; Seeley, John R.; Lewinsohn, Peter M.

2008-01-01

The study examines the influence of parental and grandparental major depressive disorder (MDD) on behavior problems in children. The results conclude that MDD in parents and grandparents may result in high levels of incorporation problems of MDD in children but don't indicate additional risk.

On the use of antithetic variates in particle transport problems

International Nuclear Information System (INIS)

Milgram, M.S.

2001-01-01

The possible use of antithetic variates as a method of variance reduction in particle transport problems is investigated, by performing some numerical experiments. It is found that if variance reduction is not very carefully defined, it is possible, with antithetic variates, to spuriously detect reduction, or not detect true reduction. Once such subtleties are overcome, it is shown that antithetic variates can reduce variance in multidimensional integration up to a point. The phenomenon of spontaneous correlation is defined and identified as the cause of failure. The surprising result that it sometimes pays to track non-contributing particle histories is demonstrated by means of a zero variance integration analogue. The principles developed in the investigation of multi-variable integration are then employed in a simple calculation of energy deposition using the EGS4 computer code. Promising results are obtained for the total energy deposition problem, but the depth/dose problem remains unsolved. Possible means of overcoming the difficulties are suggested

Major Problems and Countermeasures of Foreign Trade in China under the Background of Expanding Domestic Demand

OpenAIRE

Ruan, Wei-tong; Li, Yu-hong

2010-01-01

Starting from China's macro-economic policy level and combining with the status of foreign trade in China, major problems in the development of foreign trade are analyzed under the background of expanding domestic demand, which is guided by the macro-economy, international finance, international trade and other related disciplines. Problems are mainly the inflation, the reduction of import, the trade protection, the increase in export costs, the reduction of export, the scale shrinkage of for...

Performance of the majority voting rule in solving the density classification problem in high dimensions

Energy Technology Data Exchange (ETDEWEB)

Gomez Soto, Jose Manuel [Unidad Academica de Matematicas, Universidad Autonoma de Zacatecas, Calzada Solidaridad entronque Paseo a la Bufa, Zacatecas, Zac. (Mexico); Fuks, Henryk, E-mail: jmgomezgoo@gmail.com, E-mail: hfuks@brocku.ca [Department of Mathematics, Brock University, St. Catharines, ON (Canada)

2011-11-04

The density classification problem (DCP) is one of the most widely studied problems in the theory of cellular automata. After it was shown that the DCP cannot be solved perfectly, the research in this area has been focused on finding better rules that could solve the DCP approximately. In this paper, we argue that the majority voting rule in high dimensions can achieve high performance in solving the DCP, and that its performance increases with dimension. We support this conjecture with arguments based on the mean-field approximation and direct computer simulations. (paper)

Performance of the majority voting rule in solving the density classification problem in high dimensions

International Nuclear Information System (INIS)

Gomez Soto, Jose Manuel; Fuks, Henryk

2011-01-01

The density classification problem (DCP) is one of the most widely studied problems in the theory of cellular automata. After it was shown that the DCP cannot be solved perfectly, the research in this area has been focused on finding better rules that could solve the DCP approximately. In this paper, we argue that the majority voting rule in high dimensions can achieve high performance in solving the DCP, and that its performance increases with dimension. We support this conjecture with arguments based on the mean-field approximation and direct computer simulations. (paper)

Review of heat transfer problems associated with magnetically-confined fusion reactor concepts

International Nuclear Information System (INIS)

Hoffman, M.A.; Werner, R.W.; Carlson, G.A.; Cornish, D.N.

1976-01-01

Conceptual design studies of possible fusion reactor configurations have revealed a host of interesting and sometimes extremely difficult heat transfer problems. The general requirements imposed on the coolant system for heat removal of the thermonuclear power from the reactor are discussed. In particular, the constraints imposed by the fusion plasma, neutronics, structure and magnetic field environment are described with emphasis on those aspects which are unusual or unique to fusion reactors. Then the particular heat transfer characteristics of various possible coolants including lithium, flibe, boiling alkali metals, and helium are discussed in the context of these general fusion reactor requirements. Some specific areas where further experimental and/or theoretical work is necessary are listed for each coolant along with references to the pertinent research already accomplished. Specialized heat transfer problems of the plasma injection and removal systems are also described. Finally, the challenging heat transfer problems associated with the superconducting magnets are reviewed, and once again some of the key unsolved heat transfer problems are enumerated

Investigating Prospective Teachers' Perceived Problem-Solving Abilities in Relation to Gender, Major, Place Lived, and Locus of Control

Science.gov (United States)

Çakir, Mustafa

2017-01-01

The purpose of this study is to investigate prospective teachers' perceived personal problem-solving competencies in relation to gender, major, place lived, and internal-external locus of control. The Personal Problem-Solving Inventory and Rotter's Internal-External Locus of Control Scale were used to collect data from freshman teacher candidates…

Interpretation of quantum mechanics by the double solution theory

International Nuclear Information System (INIS)

Broglie, L. de.

1987-01-01

English translation of one of Louis de Broglie's latest articles, as a kind of gift to all physicists abroad who are not well acquainted with the double solution theory, or do not read French. Our readers will appreciate the deep physical insight expressed in this tentative theory of wave-particle dualism, a major problem unsolved to everyone's satisfaction

Phase Transitions in Planning Problems: Design and Analysis of Parameterized Families of Hard Planning Problems

Science.gov (United States)

Hen, Itay; Rieffel, Eleanor G.; Do, Minh; Venturelli, Davide

2014-01-01

There are two common ways to evaluate algorithms: performance on benchmark problems derived from real applications and analysis of performance on parametrized families of problems. The two approaches complement each other, each having its advantages and disadvantages. The planning community has concentrated on the first approach, with few ways of generating parametrized families of hard problems known prior to this work. Our group's main interest is in comparing approaches to solving planning problems using a novel type of computational device - a quantum annealer - to existing state-of-the-art planning algorithms. Because only small-scale quantum annealers are available, we must compare on small problem sizes. Small problems are primarily useful for comparison only if they are instances of parametrized families of problems for which scaling analysis can be done. In this technical report, we discuss our approach to the generation of hard planning problems from classes of well-studied NP-complete problems that map naturally to planning problems or to aspects of planning problems that many practical planning problems share. These problem classes exhibit a phase transition between easy-to-solve and easy-to-show-unsolvable planning problems. The parametrized families of hard planning problems lie at the phase transition. The exponential scaling of hardness with problem size is apparent in these families even at very small problem sizes, thus enabling us to characterize even very small problems as hard. The families we developed will prove generally useful to the planning community in analyzing the performance of planning algorithms, providing a complementary approach to existing evaluation methods. We illustrate the hardness of these problems and their scaling with results on four state-of-the-art planners, observing significant differences between these planners on these problem families. Finally, we describe two general, and quite different, mappings of planning

The Relationship between Video Game Use and a Performance-Based Measure of Persistence

Science.gov (United States)

Ventura, Matthew; Shute, Valerie; Zhao, Weinan

2013-01-01

An online performance-based measure of persistence was developed using anagrams and riddles. Persistence was measured by recording the time spent on unsolved anagrams and riddles. Time spent on unsolved problems was correlated to a self-report measure of persistence. Additionally, frequent video game players spent longer times on unsolved problems…

Management of functional dyspepsia: Unsolved problems and new perspectives

OpenAIRE

Madisch, Ahmed; Miehlke, Stephan; Labenz, Joachim

2005-01-01

The common characteristic criteria of all functional gastrointestinal (GI) disorders are the persistence and recurrence of variable gastrointestinal symptoms that cannot be explained by any structural or biochemical abnormalities. Functional dyspepsia (FD) represents one of the important GI disorders in Western countries because of its remarkably high prevalence in general population and its impact on quality of life. Due to its dependence on both subjective determinants and diverse country-s...

Identification of Genetically Modified Foods - problems and unsolved questions

DEFF Research Database (Denmark)

Pedersen, Jan W.; Eriksen, Folmer Damsted

2007-01-01

One of the points in the discussion of genetically modified organisms (GMO) is the consumers’ right to choose between foods from GMO (GM-foods) and traditionally produced foods. This discussion has led to the EU regulation requiring labelling of GM food products made from GM plants. However, since...

Unsolved problems of crystallization and melting of flexible macromolecules

International Nuclear Information System (INIS)

Wunderlich, B.

1992-01-01

The thermodynamics, kinetics, and computer simulations of crystallization and melting is discussed. The thermodynamics is shown to be well understood, although for many specific crystals not enough details for full description are available. Experiments on the crystallization kinetics of poly(ethylene) and poly(oxyethylene) in the presence of crystal nuclei as a function of molecular mass revealed that with increasing mass, the crystallization behavior deviates increasingly from that of small, rigid molecules. Instead of showing a continuously changing, linear crystallization rate with temperature through the equilibrium melting temperature, T m 0 , these flexible macromolecules show a region of practically zero crystallization rate between T m 0 and about (T m 0 - 15) K, creating a temperature region of metastability in the melt that cannot be broken by nucleation with pregrown crystals. Molecular Nucleation was proposed as a cooperative process to be of overriding importance for the description of polymer crystallization, and to be at the center of segregation of molecules of lower molecular mass by growing crystal fronts. Initial efforts to model sufficiently large crystals using Monte Carlo and molecular dynamics methods are presented. Some of the short-time intermediates in the melting, crystallization, and annealing processes seem to have little similarity to commonly assumed models of crystallization and melting and are presented as discussion topics

Direct Fuel Injection of LPG in Small Two-Stroke Engines

OpenAIRE

Yew Heng Teoh; Horizon Gitano-Briggs

2011-01-01

The commonly used carburetted two-stroke engines in developing countries have high exhaust emission and poor fuel efficiency. To meet more rigid emissions requirements, two-stroke vehicles are typically phase out in favour of four-stroke engines. The problems of ubiquitous legacy two-stroke vehicles remain unsolved by these measures and they are likely to be a major source of transport for many years to come. A number of technologies are available for solving the problems associated with two-...

Is vitamin D deficiency a major global public health problem?

Science.gov (United States)

Palacios, Cristina; Gonzalez, Lilliana

2014-10-01

Vitamin D deficiency is a major public health problem worldwide in all age groups, even in those residing in countries with low latitude, where it was generally assumed that UV radiation was adequate enough to prevent this deficiency, and in industrialized countries, where vitamin D fortification has been implemented now for years. However, most countries are still lacking data, particularly population representative data, with very limited information in infants, children, adolescents and pregnant women. Since the number of recent publications is escalating, with a broadening of the geographic diversity, the objective of the present report was to conduct a more recent systematic review of global vitamin D status, with particular emphasis in at risk groups. A systematic review was conducted in PubMed/Medline in April-June 2013 to identify articles on vitamin D status worldwide published in the last 10 years in apparently healthy individuals. Only studies with vitamin D status prevalence were included. If available, the first source selected was population-based or representative samples studies. Clinical trials, case-control studies, case reports or series, reviews, validation studies, letters, editorials, or qualitative studies were excluded. A total of 103 articles were eligible and included in the present report. Maps were created for each age group, providing an updated overview of global vitamin D status. In areas with available data, the prevalence of low vitamin D status is a global problem in all age groups, in particular in girls and women from the Middle East. These maps also evidenced the regions with missing data for each specific population groups. There is striking lack of data in infants, children and adolescents worldwide, and in most countries of South America and Africa. In conclusion, vitamin D deficiency is a global public health problem in all age groups, particularly in those from the Middle East. This article is part of a Special Issue

Human development I: Twenty Fundamental Problems of Biology, Medicine, and Neuro-Psychology Related to Biological Information

Directory of Open Access Journals (Sweden)

Tyge Dahl Hermansen

2006-01-01

Full Text Available In a new series of papers, we address a number of unsolved problems in biology today. First of all, the unsolved enigma concerning how the differentiation from a single zygote to an adult individual happens has been object for severe research for decades. By uncovering a new holistic biological paradigm that introduces an energetic-informational interpretation of reality as a new way to experience biology, these papers will try to solve the problems connected with the events of biological ontogenesis involving a fractal hierarchy, from a single cell to the function of the human brain. The problems discussed are interpreted within the frames of a universe of roomy fractal structures containing energetic patterns that are able to deliver biological information. We think biological organization is guided by energetic changes on the level of quantum mechanics, interacting with the intention that again guides the energetic conformation of the fractal structures to gain disorders or healthiness. Furthermore, we introduce two new concepts: “metamorphous top down” evolution and “adult human metamorphosis”. The first is a new evolutionary theory involving metamorphosis as a main concept of evolution. The last is tightly linked to the evolutionary principle and explains how human self-recovery is governed. Other subjects of special interest that we shall look deeper into are the immunological self-nonself discrimination, the structure and function of the human brain, the etiology and salutogenesis of mental and somatic diseases, and the structure of the consciousness of a human being. We shall criticize Szentagothai’s model for the modulated structure of the human cerebral cortex and Jerne’s theory of the immunological regulatory anti-idiotypic network.

The qualitative problem of major quotation errors, as illustrated by 10 different examples in the headache literature.

Science.gov (United States)

Tfelt-Hansen, Peer

2015-03-01

There are two types of errors when references are used in the scientific literature: citation errors and quotation errors, and these errors have in reviews mainly been evaluated quantitatively. Quotation errors are the major problem, and 1 review reported 6% major quotation errors. The objective of this listing of quotation errors is to illustrate by qualitative analysis of different types of 10 major quotation errors how and possibly why authors misquote references. The author selected for review the first 10 different consecutive major quotation errors encountered from his reading of the headache literature. The characteristics of the 10 quotation errors ranged considerably. Thus, in a review of migraine therapy in a very prestigious medical journal, the superiority of a new treatment (sumatriptan) vs an old treatment (aspirin plus metoclopramide) was claimed despite no significant difference for the primary efficacy measure in the trial. One author, in a scientific debate, referred to the lack of dilation of the middle meningeal artery in spontaneous migraine despite the fact that only 1 migraine attack was studied. The possibility for creative major quotation errors in the medical literature is most likely infinite. Qualitative evaluations, as the present, of major quotation errors will hopefully result in more general awareness of quotation problems in the medical literature. Even if the final responsibility for correct use of quotations is with the authors, the referees, the experts with the knowledge needed to spot quotation errors, should be more involved in ensuring correct and fair use of references. Finally, this paper suggests that major misleading quotations, if pointed out by readers of the journal, should, as a rule, be corrected by way of an erratum statement. © 2015 American Headache Society.

Some problems of geologic relations between the Amazon craton and east margins fold belts

International Nuclear Information System (INIS)

Almeida, F.F.M. de

1986-01-01

This paper deals with some geologic problems related to the limits between the Amazon craton and the fold belts developed at its margins during the Precambrian. These limits are diversified but clearly recognized. To the north, the Araguaia-Tocantins fold belt, of presumed Middle Proterozoic age, is separated from the cratonic block by a deep marginal fracture zone permeated by mafic and ultramafic rocks. The geologic, magmatic and aeromagnetic characteristics of this zone point out the presence of deep faults, supposed to be of Middle Proterozoic age. The southern Paraguay fold belt constitutes and accurated zone of linear structures supposed to be of Late Proterozoic development. Despite the great increase of knowledge during the last ten years many tectonic, stratigraphic and geochronologic problems remain unsolved. The aim of this paper is to point out some of these problems and suggest specific studies to solve them. (author)

Turbulence Nature and the Inverse Problem

CERN Document Server

Pyatnitsky, L. N

2009-01-01

Hydrodynamic equations well describe averaged parameters of turbulent steady flows, at least in pipes where boundary conditions can be estimated. The equations might outline the parameters fluctuations as well, if entry conditions at current boundaries were known. This raises, in addition, the more comprehensive problem of the primary perturbation nature, noted by H.A. Lorentz, which still remains unsolved. Generally, any flow steadiness should be supported by pressure waves emitted by some external source, e.g. a piston or a receiver. The wave plane front in channels quickly takes convex configuration owing to Rayleigh's law of diffraction divergence. The Schlieren technique and pressure wave registration were employed to investigate the wave interaction with boundary layer, while reflecting from the channel wall. The reflection induces boundary-layer local separation and following pressure rapid increase within the perturbation zone. It propagates as an acoustic wave packet of spherical shape, bearing oscil...

Tactics Employed and Problems Encountered by University English Majors in Hong Kong in Using a Dictionary

Science.gov (United States)

Chan, Alice Yin Wa

2005-01-01

Building on the results of a small-scale survey which investigated the general use of dictionaries by university English majors in Hong Kong using a questionnaire survey and their specific use of dictionaries using an error correction task, this article discusses the tactics these students employed and the problems they encountered when using a…

The qualitative problem of major quotation errors, as illustrated by 10 different examples in the headache literature

DEFF Research Database (Denmark)

Tfelt-Hansen, Peer

2015-01-01

There are two types of errors when references are used in the scientific literature: citation errors and quotation errors, and these errors have in reviews mainly been evaluated quantitatively. Quotation errors are the major problem, and 1 review reported 6% major quotation errors. The objective...... of this listing of quotation errors is to illustrate by qualitative analysis of different types of 10 major quotation errors how and possibly why authors misquote references. The author selected for review the first 10 different consecutive major quotation errors encountered from his reading of the headache...... literature. The characteristics of the 10 quotation errors ranged considerably. Thus, in a review of migraine therapy in a very prestigious medical journal, the superiority of a new treatment (sumatriptan) vs an old treatment (aspirin plus metoclopramide) was claimed despite no significant difference...

Structural qualia: a solution to the hard problem of consciousness.

Science.gov (United States)

Loorits, Kristjan

2014-01-01

The hard problem of consciousness has been often claimed to be unsolvable by the methods of traditional empirical sciences. It has been argued that all the objects of empirical sciences can be fully analyzed in structural terms but that consciousness is (or has) something over and above its structure. However, modern neuroscience has introduced a theoretical framework in which also the apparently non-structural aspects of consciousness, namely the so called qualia or qualitative properties, can be analyzed in structural terms. That framework allows us to see qualia as something compositional with internal structures that fully determine their qualitative nature. Moreover, those internal structures can be identified which certain neural patterns. Thus consciousness as a whole can be seen as a complex neural pattern that misperceives some of its own highly complex structural properties as monadic and qualitative. Such neural pattern is analyzable in fully structural terms and thereby the hard problem is solved.

Structural qualia: a solution to the hard problem of consciousness

Directory of Open Access Journals (Sweden)

Kristjan eLoorits

2014-03-01

Full Text Available The hard problem of consciousness has been often claimed to be unsolvable by the methods of traditional empirical sciences. It has been argued that all the objects of empirical sciences can be fully analyzed in structural terms but that consciousness is (or has something over and above its structure. However, modern neuroscience has introduced a theoretical framework in which also the apparently non-structural aspects of consciousness, namely the so called qualia or qualitative properties, can be analyzed in structural terms. That framework allows us to see qualia as something compositional with internal structures that fully determine their qualitative nature. Moreover, those internal structures can be identified which certain neural patterns. Thus consciousness as a whole can be seen as a complex neural pattern that misperceives some of its own highly complex structural properties as monadic and qualitative. Such neural pattern is analyzable in fully structural terms and thereby the hard problem is solved.

Intergenerational Transmission of Internalizing Problems: Effects of Parental and Grandparental Major Depressive Disorder on Child Behavior

Science.gov (United States)

Pettit, Jeremy W.; Olino, Thomas M.; Roberts, Robert E.; Seeley, John R.; Lewinsohn, Peter M.

2008-01-01

Effects of lifetime histories of grandparental (G1) and parental (G2) major depressive disorder (MDD) on children's (G3) internalizing problems were investigated among 267 G3 children (ages 2-18 years) who received Child Behavior Checklist (CBCL) ratings and had diagnostic data available on 267 biological G2 parents and 527 biological G1…

Heart Lesion After the First Attack of the Rheumatic Fever 22 Years Experience in Single Centre

OpenAIRE

Bejiqi, Ramush A.; Retkoceri, Ragip; Zeka, Naim; Bejiqi, Hana; Retkoceri, Arber

2015-01-01

Background: Acute rheumatic fever and its sequels, rheumatic heart diseases, remain major unsolved preventable health problems in Kosovo population, particularly among the disadvantages indigenous Albanian and Egyptians people. In Kosovo, despite of performing secondary prophylaxis with benzathine penicillin, acute rheumatic fever hospitalization rates have remained essentially unchanged for the last 20 years. The role of echocardiography in the diagnosis of acute rheumatic carditis was estab...

Reformation of organization and realization of budgetary process: basic directions, problems and ways of their solution

Directory of Open Access Journals (Sweden)

E.B. Ponomarenko

2015-12-01

Full Text Available The article is dedicated to the research of the basic problems of organization and realization of budgetary process in the country on the modern stage. A budgetary process is one of the main levers which is able really to provide management of an economy under conditions of a market economy. Organizational and administrative structures of the budgetary process are ineffective in Ukraine. In spite of more than twenty-year old history, the budgetary process of Ukraine has the row of unsolved problems. For this reason there is the necessity in deep theoretical rethinking and methodological work at approaches to the budgetary process. We consider it is wise to find out the basic problems which arise during organization and realization of the budgetary process in Ukraine. The study of the matter results in the complex of recommendations which are able to provide effective realization of the budgetary process in Ukraine and solve a number of problem questions.

Wireline coring/open center reaming: Technical problems and solutions

International Nuclear Information System (INIS)

Fehr, G.

1996-01-01

At the 1993 ASME Energy Technology Conference, a paper, ''Field Experience with Wireline Coring through a Dual Wall Drilling System'', was presented. It described the initial scientific drilling which started in the spring of 1992 using wireline coring within a 9 5/8 inch dual wall drill pipe through an open center reaming bit, and some of the improvements made since the prototype drilling tests. New and as yet unsolved problems were identified. This follow-on work brings the industry up-to-date with a survey of how these difficulties have been solved, or, if not solved, the status of the effort made for each of the air coring/reaming technical challenges on the Yucca Mountain Site Characterization Project at the US Department of Energy Nevada Test Site

Fundamental problems of gauge field theory

International Nuclear Information System (INIS)

Velo, G.; Wightman, A.S.

1986-01-01

As a result of the experimental and theoretical developments of the last two decades, gauge field theory, in one form or another, now provides the standard language for the description of Nature; QCD and the standard model of the electroweak interactions illustrate this point. It is a basic task of mathematical physics to provide a solid foundation for these developments by putting the theory in a physically transparent and mathematically rigorous form. The lecture notes collected in this volume concentrate on the many unsolved problems which arise here, and on the general ideas and methods which have been proposed for their solution. In particular, the use of rigorous renormalization group methods to obtain control over the continuum limit of lattice gauge field theories, the exploration of the extraordinary enigmatic connections between Kac-Moody-Virasoro algebras and string theory, and the systematic use of the theory of local algebras and indefinite metric spaces to classify the charged C* states in gauge field theories are mentioned

One of the Major Problems in Tuberculosis Control: Adherence to Therapy

Directory of Open Access Journals (Sweden)

Belguzar Kara

2009-02-01

Full Text Available Abstract: Although tuberculosis (TB is a preventable and curable disease, approximately one third of the world’s population is infected with the TB bacillus. Tuberculosis is a major public health problem in especially developing countries. Nonadherence to TB therapy regimes is common, as treatment is difficult and requires long courses of multiple antibiotics. It is estimated that the rate of nonadherence to TB treatment ranges from 20 to 80%. Nonadherence to TB treatment is the most serious barrier in disease control because incomplete treatment may result in prolonged infectiousness, drug resistance, relapse and death. However, handling the factors affecting adherence to treatment for the patients may increase the efficiency of the treatment and help to reach better health outcomes. This article reviews evidence regarding adherence to TB treatment in patients and affecting factors and makes recommendations for health care professionals. [TAF Prev Med Bull 2009; 8(1.000: 75-82

On the doping problem of CdTe films: The bismuth case

Energy Technology Data Exchange (ETDEWEB)

Vigil-Galan, O. [Escuela Superior de Fisica y Matematicas del IPN, Edif. 9, UPALM, 07738 Mexico, D. F. (Mexico); Brown, M. [Department of Physics and Astronomy, The University of Toledo, 43606 Toledo, OH (United States); Ruiz, C.M. [Depto. Fisica de Materiales, Universidad Autonoma de Madrid, 28049 Madrid (Spain); Vidal-Borbolla, M.A. [Instituto de Investigacion en Comunicacion Optica, Av. Karakorum 1470, Lomas 4a. Secc., 78210 San Luis Potosi, SLP (Mexico); Ramirez-Bon, R. [CINVESTAV-IPN, U. Queretaro, Libramiento Norponiente No. 2000, Fracc. Real de Juriquilla, 76230 Santiago de Queretaro, Qro. (Mexico); Sanchez-Meza, E. [Escuela Superior de Fisica y Matematicas del IPN, Edif. 9, UPALM, 07738 Mexico, D. F. (Mexico); Tufino-Velazquez, M. [Escuela Superior de Fisica y Matematicas del IPN, Edif. 9, UPALM, 07738 Mexico, D. F. (Mexico)], E-mail: mtufinovel@yahoo.com.mx; Calixto, M. Estela [Escuela Superior de Fisica y Matematicas del IPN, Edif. 9, UPALM, 07738 Mexico, D. F. (Mexico); Compaan, A.D. [Department of Physics and Astronomy, The University of Toledo, 43606 Toledo, OH (United States); Contreras-Puente, G. [Escuela Superior de Fisica y Matematicas del IPN, Edif. 9, UPALM, 07738 Mexico, D. F. (Mexico)

2008-08-30

The controlled increase of hole concentration is an important issue and still an unsolved problem for polycrystalline CdTe-based solar cells. The typical hole concentration of as-grown CdTe thin-films goes up to 10{sup 13} cm{sup -3}, depending on the specific growth technique. The highest electron concentration obtained for CdS, the suitable window partner material of CdTe, is around 10{sup 15} cm{sup -3}. Thus, the PV-performance of a CdS/CdTe device can be optimized if the hole concentration in CdTe is increased. We have faced up this problem by studying the electrical properties of two types of CdTe films: CdTe films grown by Close Space Vapor Transport using a CdTe:Bi powder as the starting material and CdTe sputtered films doped by implantation with different Bi-doses. Temperature-dependent resistivity and Hall effect measurements and a discussion on the efficiency of both doping processes are presented.

On the doping problem of CdTe films: The bismuth case

International Nuclear Information System (INIS)

Vigil-Galan, O.; Brown, M.; Ruiz, C.M.; Vidal-Borbolla, M.A.; Ramirez-Bon, R.; Sanchez-Meza, E.; Tufino-Velazquez, M.; Calixto, M. Estela; Compaan, A.D.; Contreras-Puente, G.

2008-01-01

The controlled increase of hole concentration is an important issue and still an unsolved problem for polycrystalline CdTe-based solar cells. The typical hole concentration of as-grown CdTe thin-films goes up to 10 13 cm -3 , depending on the specific growth technique. The highest electron concentration obtained for CdS, the suitable window partner material of CdTe, is around 10 15 cm -3 . Thus, the PV-performance of a CdS/CdTe device can be optimized if the hole concentration in CdTe is increased. We have faced up this problem by studying the electrical properties of two types of CdTe films: CdTe films grown by Close Space Vapor Transport using a CdTe:Bi powder as the starting material and CdTe sputtered films doped by implantation with different Bi-doses. Temperature-dependent resistivity and Hall effect measurements and a discussion on the efficiency of both doping processes are presented

Three P’s in Cosmology: Progress, Problems, and Perspectives

Directory of Open Access Journals (Sweden)

Dolgov A.D.

2014-04-01

Full Text Available A review on the development of cosmology for a diverse audience is presented. The first historical part is devoted to the works done half a century ago with an emphasize to those performed in Russia (or more precisely, in the Soviet Union. Then the recent data on the cosmic microwave background raditation is discussed and the impact of these data on the neutrino mass and the number of neutrino species is considered. The latter is compared with the results obtained from the big bang nucleosynthesis. Next, a short description and history of the cosmological inflation is presented. The basics of the standard cosmological model and the problems of dark matter and dark energy are considered at the end of the fist section entitled “Progress”. In the next short section, “Problems”, one can find a list of the unsolved cosmological and astrophysical problems, which is by no means fully comprehensive. The last supershort section contains a few words about the perspectives of future development.

Standardization for oxygen isotope ratio measurement - still an unsolved problem.

Science.gov (United States)

Kornexl; Werner; Gehre

1999-07-01

Numerous organic and inorganic laboratory standards were gathered from nine European and North American laboratories and were analyzed for their delta(18)O values with a new on-line high temperature pyrolysis system that was calibrated using Vienna standard mean ocean water (VSMOW) and standard light Antartic precipitation (SLAP) internationally distributed reference water samples. Especially for organic materials, discrepancies between reported and measured values were high, ranging up to 2 per thousand. The reasons for these discrepancies are discussed and the need for an exact and reliable calibration of existing reference materials, as well as for the establishment of additional organic and inorganic reference materials is stressed. Copyright 1999 John Wiley & Sons, Ltd.

The Scottish book mathematics from the Scottish café, with selected problems from the new Scottish book

CERN Document Server

Mauldin, R Daniel

2015-01-01

The second edition of this book updates and expands upon a historically important collection of mathematical problems first published in the United States by Birkhäuser in 1981. These problems serve as a record of the informal discussions held by a group of mathematicians at the Scottish Café in Lwów, Poland, between the two world wars. Many of them were leaders in the development of such areas as functional and real analysis, group theory, measure and set theory, probability, and topology. Finding solutions to the problems they proposed has been ongoing since World War II, with prizes offered in many cases to those who are successful. In the 35 years since the first edition published, several more problems have been fully or partially solved, but even today many still remain unsolved and several prizes remain unclaimed. In view of this, the editor has gathered new and updated commentaries on the original 193 problems. Some problems are solved for the first time in this edition. Included again in full are ...

Somatic APC mosaicism and oligogenic inheritance in genetically unsolved colorectal adenomatous polyposis patients.

Science.gov (United States)

Ciavarella, Michele; Miccoli, Sara; Prossomariti, Anna; Pippucci, Tommaso; Bonora, Elena; Buscherini, Francesco; Palombo, Flavia; Zuntini, Roberta; Balbi, Tiziana; Ceccarelli, Claudio; Bazzoli, Franco; Ricciardiello, Luigi; Turchetti, Daniela; Piazzi, Giulia

2018-03-01

Germline variants in the APC gene cause familial adenomatous polyposis. Inherited variants in MutYH, POLE, POLD1, NTHL1, and MSH3 genes and somatic APC mosaicism have been reported as alternative causes of polyposis. However, ~30-50% of cases of polyposis remain genetically unsolved. Thus, the aim of this study was to investigate the genetic causes of unexplained adenomatous polyposis. Eight sporadic cases with >20 adenomatous polyps by 35 years of age or >50 adenomatous polyps by 55 years of age, and no causative germline variants in APC and/or MutYH, were enrolled from a cohort of 56 subjects with adenomatous colorectal polyposis. APC gene mosaicism was investigated on DNA from colonic adenomas by Sanger sequencing or Whole Exome Sequencing (WES). Mosaicism extension to other tissues (peripheral blood, saliva, hair follicles) was evaluated using Sanger sequencing and/or digital PCR. APC second hit was investigated in adenomas from mosaic patients. WES was performed on DNA from peripheral blood to identify additional polyposis candidate variants. We identified APC mosaicism in 50% of patients. In three cases mosaicism was restricted to the colon, while in one it also extended to the duodenum and saliva. One patient without APC mosaicism, carrying an APC in-frame deletion of uncertain significance, was found to harbor rare germline variants in OGG1, POLQ, and EXO1 genes. In conclusion, our restrictive selection criteria improved the detection of mosaic APC patients. In addition, we showed for the first time that an oligogenic inheritance of rare variants might have a cooperative role in sporadic colorectal polyposis onset.

The Academic, Administrative, Economic, Social, and Psychological Problems Faced by Students of Textile and Clothing Major at King Abdul-Aziz University

Science.gov (United States)

Alsubyani, Noor Abdulhadi

2017-01-01

The purpose of this study is to investigate the academic, administrative, economic, social, and psychological problems faced by students of Textile and fabric major at King Abdul-Aziz University. To achieve this purpose, a questionnaire was designed and distributed to a sample of students in the Textile and fabric major, after the use of…

Managing State Debt of Ukraine: Problems and Directions of Optimisation

Directory of Open Access Journals (Sweden)

Syzrantsev Hlib O.

2013-12-01

Full Text Available The modern state of the state debt of Ukraine and future forecasts of its increase make look for new methods of debt management. That is why the goal of the article lies in revelation of main problems of state debt management in Ukraine on the basis of the analysis of its modern state and also in scientific justification of conceptual grounds of improvement of the mechanism of state debt management and servicing under modern conditions. Analysing, systemising and generalising scientific works of many scientists, the article considers the state debt as an instrument of macro-economic regulation, provides dynamics of growth of external and internal state debts. In the result of the study the article reveals a number of unsolved problems in the sphere of debt management. Due to this the article offers conceptual measures on management of the state debt of Ukraine. The prospect of further studies is the search for state debt management methods that would allow reduction of the debt load on the state budget and economy of Ukraine.

Interdisciplinary Project Experiences: Collaboration between Majors and Non-Majors

Science.gov (United States)

Smarkusky, Debra L.; Toman, Sharon A.

2014-01-01

Students in computer science and information technology should be engaged in solving real-world problems received from government and industry as well as those that expose them to various areas of application. In this paper, we discuss interdisciplinary project experiences between majors and non-majors that offered a creative and innovative…

On the problem of finding a suitable distribution of students to universities in Germany

Science.gov (United States)

Schneider, Johannes J.; Hirtreiter, Christian; Morgenstern, Ingo

2009-10-01

For many years, the problem of how to distribute students to the various universities in Germany according to the preferences of the students has remained unsolved. Various approaches, like the centralized method to let a central agency organize the distribution to the various universities or the decentralized method to let the students apply directly at their preferred universities, turned out to lead to a significant fraction of frustrated students ending up at universities not being on their preference list or even not having a place to study at all. With our centralized approach, we are able to decrease the fraction of frustrated students as well as the bureaucratic expenses for applicants and universities drastically.

Hierarchies of fundamental constants (to items Nos 16, 17, and 27 from Ginzburg's list)

International Nuclear Information System (INIS)

Rubakov, Valerii A

2007-01-01

Current understanding of major unsolved problems in particle physics and cosmology suggests that physics is facing serious challenges and that the existing view of how the laws of Nature work may possibly (though not necessarily) be substantially extended in the near future. From this standpoint, experiments at the LHC proton collider due to start shortly at CERN are going to make a crucial impact. (oral issue of the journal 'uspekhi fizicheskikh nauk')

The ICMJE Recommendations and pharmaceutical marketing--strengths, weaknesses and the unsolved problem of attribution in publication ethics.

Science.gov (United States)

Matheson, Alastair

2016-04-04

The International Committee of Medical Journal Editors (ICMJE) Recommendations set ethical and editorial standards for article publication in most leading medical journals. Here, I examine the strengths and weaknesses of the Recommendations in the prevention of commercial bias in industry-financed journal literature, on three levels - scholarly discourse, article content, and article attribution. With respect to overall discourse, the most important measures in the ICMJE Recommendations are for enforcing clinical trial registration and controlling duplicate publication. With respect to article content, the ICMJE promotes stringent author accountability and adherence to established reporting standards. However, the ICMJE accepts the use of commercial editorial teams to produce manuscripts, which is a potential source of bias, and accepts private company ownership and analysis of clinical trial data. New ICMJE guidance on data sharing will address but not eliminate problems of commercial data access. With respect to attribution, the Recommendations oppose guest authorship and encourage clear documentation of author contributions. However, they exclude writers from coauthorship; provide no specific advice on the attribution of commercial literature, for instance with respect to company authorship, author sequence or prominent commercial labeling; and endorse the use of fine print and euphemism. The ICMJE requires detailed author interest disclosures, but overlooks the interests of non-authors and companies, and does not recommend that interests most salient to the publication are highlighted. Together, these weaknesses facilitate "advocacy"-based marketing, in which literature planned, financed and produced by companies is fronted by academics, enabling commercial messages to be presented to customers by their respected clinical peers rather than companies themselves. The ICMJE Recommendations set important research and reporting standards, without which commercial

Assessing Major Adjustment Problems of Freshman Students in ...

African Journals Online (AJOL)

Ethiopian Journal of Education and Sciences ... The data was analyzed by using both descriptive and inferential statistical methods. ... in Jimma University experience social adjustment problems than educational and personalpsychological, ...

La educación superior en américa latina: ¿problemas insolubles o recetas inadecuadas? higher education in latin america: unsolvable problems or misleading recipes?

Directory of Open Access Journals (Sweden)

adriana chiroleu

2011-11-01

Full Text Available Este texto presenta algunas tendencias comunes en el ámbito regional y varios de los principales nudos problemáticos que obstaculizan un desarrollo armónico de su educación superior. Consideramos al respecto, que la continuidad de las políticas públicas pergeñadas en los 90, ha bloqueado la posibilidad de resolver problemas medulares. Focalizaremos especialmente en tres procesos: la expansión de la cobertura sin reducción de las desigualdades sociales ni inclusión plena en la educación superior, el desarrollo de procesos de evaluación institucional sin mejoramiento efectivo de la calidad de los aprendizajes y el énfasis otorgado a la formación de profesionales que subalterniza el compromiso y la responsabilidad social de los universitarios.This paper points out some common tendencies of the Latin America region and several troublesome aspects that hinder a harmonic development of its Higher Education. We consider that the sustainability of the public policies sketched out in the '90s, has blocked the possibility of solving major problems. We will pay extra attention to the three following processes: the expansion of the outreach without the reduction of either social inequalities or a fully inclusion in Higher Education; the development of institutional evaluation processes without an improvement on the quality of the learning processes; and last but not least, the emphasis given to professional trainings instead of the commitment and the social responsibility of the university actors.

Adolescent Leisure-Time Activity and Problem Behavior: The Integration of Three Major Explanatory Theories as a New

OpenAIRE

Yost, Gail

1995-01-01

Adolescence has in recent decades gained attention as being salient for study of social trends. Increases in youth social problems are seen nationally, statewide, and locally. They include substance abuse, precocious sexual activity, related consequences of pregnancy and STDs, suicide and depression, truancy, running away, crime against property, and violent crime against persons. This study integrates three major explanatory theories of adolescent behavior into a macro-synthesis. R. Jesser's...

Open problems and future prospects for hypernuclear physics

International Nuclear Information System (INIS)

Dover, C.B.

1992-01-01

We appraise the current status of our knowledge of hypernuclear structure physics, and emphasize the unsolved problems. The prospects for significant advances in high resolution hypernuclear spectroscopy with CW electron beams at CEBAF or intense pion beams at the proposed PILAC facility at LPF are discussed. These facilities could greatly extend our understanding of strangeness S = -1 hypernuclear systems. For S = -2 systems, new events have been seen in a (K - ,K + ) hybrid counter-emulsion experiment at KEK in Japan. We give a theoretical interpretation of one of these events, as well as some further possibilities for the exploration of ΛΛ hypernuclear spectroscopy via Ξ - -atoms. We mention some possible enhancements of (K - ,K + ) or (K - ,K 0 ) cross sections to discrete states, due to ΞN-ΛΛ configuration mixing in a shell model description of S = -2 hypernuclei. Finally, we explore the possibilities for producing multi-strange nuclei or droplets of strange quark matter (''strangelets'') in relativistic heavy ion collisions

Social Structure Simulation and Inference Using Artificial Intelligence Techniques

Science.gov (United States)

2005-06-15

human languages is an unsolved (and possibly unsolvable) problem. Thus, let us only use English grammar as a trampoline towards mapping semantics of...editing screen. This behavior of the interface allows for fast manual data entry from text sources. For example, to code a statement ”Hamas was headed by

[The social hygiene problems in the operator work of hydroelectric power station workers and the means for enhancing work capacity].

Science.gov (United States)

Karakashian, A N; Lepeshkina, T R; Ratushnaia, A N; Glushchenko, S S; Zakharenko, M I; Lastovchenko, V B; Diordichuk, T I

1993-01-01

Weight, tension and harmfulness of professional activity, peculiarities of labour conditions and characteristics of work, shift dynamics of operative personnel's working capacity were studied in the course of 8-hour working day currently accepted at hydroelectric power stations (HEPS) and experimental 12-hour schedule. Working conditions classified as "admissible", positive dynamics of operators' state, their social and material contentment were a basis for 12-hour two-shift schedule to be recommended as more appropriate. At the same time, problem of optimal shift schedules for operative personnel of HEPS remains unsolved and needs to be further explored.

The effects of problem-based learning on the self-efficacy and attitudes of beginning biology majors

Science.gov (United States)

Rajab, Adel Mohammad

The problem of low persistence of science majors has resulted in calls for changes in undergraduate instruction toward environments that foster positive self-efficacy among beginning science majors. Low science self-efficacy and poor attitudes toward science may contribute to high attrition rates of science majors. Classroom environments that foster positive self-efficacy development include pedagogies that promote authentic learning contexts and involve collaborative learning teams. Problem-based learning (PBL) is an instructional model that attempts to create both conditions and may provide every source of information needed for the development of self-efficacy (i.e., mastery experiences, vicarious experiences, verbal persuasion, and physiological states) as postulated by Albert Bandura. The degree to which these sources of self-efficacy are delivered to individuals within a PBL group may depend on how the group members interact and how students perceive the PBL process itself. This study examined the development of biology self-efficacy and attitudes among biology majors in a PBL setting and in a traditional lecture-based setting. Specifically, this project investigated changes in students' biology self-efficacy beliefs, mediating aspects of PBL in self-efficacy development, the relationship between PBL processes and group collective efficacy, the predictive nature of entering self-efficacy levels on attitudes toward PBL and mid-term grades, and changes in student attitudes toward biology. The study design was quasi-experimental and included quantitative pre- and post-surveys, qualitative interviews, and classroom observations. Findings revealed that students enrolled in a PBL class exhibited greater gains in biology self-efficacy and were likely to report more favorable attitudes toward biology compared to students enrolled in a traditional class. The aspects of PBL that most accounted for these findings were students' ownership of the learning process, their

[Major ethical problems in contemporary medicine].

Science.gov (United States)

Roa, A

1983-11-01

The ethical distinction between good and evil has preoccupied man since the beginning of human history. Man, unlike other animals, is capable of comparing himself with his peers; this ability leads to a constant concern with the image he is projecting rather than with becoming truly good. Ethical principles may be subordinated to other demands of the personal image, but personal goodness can only be achieved by constant effort throughout life. The medical doctor is occupied in curing the ill, but must also be preoccupied by the welfare of the patient. In the present atmosphere of abdication of ethics in the international, national, and personal realms, an abdication of medical ethics is also apparent in the dehumanization of medical attitudes at all levels and in the substitution of personal interest instead of concern for the welfare of others. Violations of medical confidences are another example. The question of whether or not to tell the truth about their conditions to dying patients should be considered in the light of the higher goal of preserving the patient's dignity as well as emotional and physical health. Ethical dilemmas are involved in the increasing resort to technology within medicine and to its occasionally indiscriminate, inappropriate, or inappropriately withheld use. A related issue is the elevation of specializations above general clinical medicine. The frantic desire to maintain the body in a young-looking state through cosmetic surgery and other means may lead to neglect of the inner life and to other vices; the physician should set an example by enriching himself through reading, art, and other means. To the extent that contraceptive usage forms part of a refusal to sacrifice for others and of the need for constant pleasure without responsibility, it is a serious ethical problem. Artificial insemination with sperm of men considered genetically superior, in vitro fertilization, and genetic engineering are associated with very complex ethical

DeepQA: Improving the estimation of single protein model quality with deep belief networks

OpenAIRE

Cao, Renzhi; Bhattacharya, Debswapna; Hou, Jie; Cheng, Jianlin

2016-01-01

Background Protein quality assessment (QA) useful for ranking and selecting protein models has long been viewed as one of the major challenges for protein tertiary structure prediction. Especially, estimating the quality of a single protein model, which is important for selecting a few good models out of a large model pool consisting of mostly low-quality models, is still a largely unsolved problem. Results We introduce a novel single-model quality assessment method DeepQA based on deep belie...

Prime Obsession: Bernhard Riemann and the Greatest Unsolved Problem in Mathematics

National Research Council Canada - National Science Library

Derbyshire, John

2003-01-01

.... Is the hypothesis true or false?Riemann's basic inquiry, the primary topic of his paper, concerned a straightforward but nevertheless important matter of arithmetic defining a precise formula to track and identify the occurrence...

Influence of parental and grandparental major depressive disorder on behavior problems in early childhood: a three-generation study.

Science.gov (United States)

Olino, Thomas M; Pettit, Jeremy W; Klein, Daniel N; Allen, Nicholas B; Seeley, John R; Lewinsohn, Peter M

2008-01-01

This aim of this study was to examine the influence of grandparental (G1) and parental (G2) major depressive disorder (MDD) and other forms of psychopathology on behavior problems in very young offspring (G3). Oregon Adolescent Depression Project (OADP) participants who had children over a 3-year period were invited to participate in a study of infant and child development. We attempted to collect diagnostic history from the original OADP (G2) participants, their coparents, the parents of the original OADP participants (G1), and the parents of the coparents. Child (G3) outcomes at 24 months of age were based on parent reports of behavior problems. Univariate correlations indicated that G1 and G2 familial loadings for MDD were associated with higher levels of G3 internalizing and externalizing behavior problems. Multiple regression analyses revealed a significant interaction between G1 and G2 MDD on G3 internalizing (but not externalizing) behavior problems. A higher familial loading for MDD in either the parental or grandparental generation was associated with elevated grandchild internalizing problems, but higher loadings for MDD in both generations did not convey additional risk. Parental MDD and grandparental MDD are both associated with elevated levels of internalizing problems in young grandchildren, but MDD in both the G1 and G2 generations does not confer additional risk. One important implication is that MDD in the grandparental generation is associated with increased risk to grandchildren even in the absence of parental MDD. Future studies should examine the mechanisms through which grandparental psychopathology influences behavior problems in grandchildren.

Why finding costs are now a major problem [in the US petroleum industry

International Nuclear Information System (INIS)

Gaddis, D.; Brock, H.; Boynton, C.

1993-01-01

A major problem facing the US petroleum industry is the higher average finding costs that now exist within the US compared to the average finding costs outside the US. It has been argued that federal lands and offshore areas need to be open for drilling in order to reduce average finding costs in the US. Certainly, the development of a national energy policy must acknowledge the importance of finding costs. Financial analysts for some time have acknowledged the importance of finding costs in evaluating individual energy firms. Analysts expect mergers when it is cheaper for companies to purchase reserves than to find them. Just as industry-average finding costs are a key determinant of long-term market prices for oil and gas, relative finding costs are a key determinant of a company's stock market value. Division managers are now judged regularly by top management on the basis of relative finding costs. The heavy use of finding costs data is causing its own problems, however, because there is as yet no standard for calculating and reporting those costs. This article analyzes the strengths and weaknesses of conventional techniques for determining finding costs. Our goal is a finding costs measure that is a reliable indicator of future profitability. Conceptually, a finding cost figure is a measurement of how much it costs a company to find a barrel of oil or an mcf of gas. The figure is arrived at by dividing the figure for costs incurred during a specified period by the volume (barrels or mcfs) of reserve added during the same period. (author)

[Matters of identifying the categories of discrepancy between diagnoses as a part of the problem of organizing the clinical expert work of a postmortem service].

Science.gov (United States)

Zaĭrat'iants, O V

2009-01-01

Whether the categories of a discrepancy between diagnoses should not be identified, which has been put by I. A. Kazantseva, is supported by the Society of Pathologists. The ranking of diagnostic discrepancies has been already subject to criticism in a number of standard guidance publications. However, this matter is a part of the unsolved problem of the clinical expert work of a postmortem service. Many regions have elaborated and approved their own principles of its organization. The standards of the Russian Agency are the most important achievement in assuring orderliness of its work. The problem requires further initiatives of the Russian Society of Pathologists and its close interaction with the Ministry of Health and Social Development in approving the relevant normative documents as soon as possible.

Isolated thoughts and feelings and unsolved concerns: adolescents' and parents' perspectives on living with type 1 diabetes - a qualitative study using visual storytelling.

Science.gov (United States)

Castensøe-Seidenfaden, Pernille; Teilmann, Grete; Kensing, Finn; Hommel, Eva; Olsen, Birthe Susanne; Husted, Gitte Reventlov

2017-10-01

To explore and describe the experiences of adolescents and their parents living with type 1 diabetes, to identify their needs for support to improve adolescents' self-management skills in the transition from child- to adulthood. Adolescents with type 1 diabetes often experience deteriorating glycaemic control and distress. Parents are important in adolescents' ability to self-manage type 1 diabetes, but they report anxiety and frustrations. A better understanding of the challenges adolescents and parents face, in relation to the daily self-management of type 1 diabetes, is important to improve clinical practice. A qualitative explorative study using visual storytelling as part of individual interviews. A purposive sample of nine adolescents and their parents (seven mothers, six fathers) took photographs illustrating their experiences living with type 1 diabetes. Subsequently, participants were interviewed individually guided by participants' photographs and a semistructured interview guide. Interviews were analysed using thematic analysis. Four major themes were consistent across adolescents and their parents: (1) striving for safety, (2) striving for normality, (3) striving for independence and (4) worrying about future. Although adolescents and parents had same concerns and challenges living with type 1 diabetes, they were experienced differently. Their thoughts and feelings mostly remained isolated and their concerns and challenges unsolved. The concerns and challenges adolescents and their parents face in the transition from child- to adulthood are still present despite new treatment modalities. Parents are fundamental in supporting the adolescents' self-management-work; however, the parties have unspoken concerns and challenges. Healthcare providers should address the parties' challenges and concerns living with type 1 diabetes to diminish worries about future including fear of hypoglycaemia, the burden of type 1 diabetes and the feeling of being incompetent

Nuclear Power Plant Construction Contracts: A Review of the Major Problems

International Nuclear Information System (INIS)

Crawford, B.B.

1977-01-01

This paper analyses the problems raised by nuclear power plant construction contracts. To the extent these contracts can be defined as devices for allocating responsibilities and risks between the Contracting Parties, the author notes that the 'responsibilities' aspect presents no problem peculiar to the nuclear sector and that difficulties mainly stem from co-ordination of work. On the other hand, the list of problems linked to 'nuclear contract risks' is long: uncertainties in the licensing procedure and export licenses, changes in pricing due to inflation, imprevision and force majeure theories, protection of proprietary information, operator's civil liability for nuclear incidents. (NEA) [fr

PREFACE: Open Problems in Nuclear Structure Theory: Introduction Open Problems in Nuclear Structure Theory: Introduction

Science.gov (United States)

Dobaczewski, Jacek

2010-06-01

Nuclear structure theory is a domain of physics faced at present with great challenges and opportunities. A larger and larger body of high-precision experimental data has been and continues to be accumulated. Experiments on very exotic short-lived isotopes are the backbone of activity at numerous large-scale facilities. Over the years, tremendous progress has been made in understanding the basic features of nuclei. However, the theoretical description of nuclear systems is still far from being complete and is often not very precise. Many questions, both basic and practical, remain unanswered. The goal of publishing this special focus issue of Journal of Physics G: Nuclear and Particle Physics on Open Problems in Nuclear Structure Theory (OPeNST) is to construct a fundamental inventory thereof, so that the tasks and available options become more clearly exposed and that this will help to stimulate a boost in theoretical activity, commensurate with the experimental progress. The requested format and scope of the articles on OPeNST was quite flexible. The journal simply offered the possibility to provide a forum for the material, which is very often discussed at conferences during the coffee breaks but does not normally have sufficient substance to form regular publications. Nonetheless, very often formulating a problem provides a major step towards its solution, and it may constitute a scientific achievement on its own. Prospective authors were therefore invited to find their own balance between the two extremes of very general problems on the one hand (for example, to solve exactly the many-body equations for a hundred particles) and very specific problems on the other hand (for example, those that one could put in one's own grant proposal). The authors were also asked not to cover results already obtained, nor to limit their presentations to giving a review of the subject, although some elements of those could be included to properly introduce the subject matter

[Current issues, problems and prospects of tension-free hernioplasty (review)].

Science.gov (United States)

2014-01-01

In the present study there are discussed modern methods of the tension free hernioplastics, the complications associated with them and technical difficulties, up-to-date views and the perspectives of the issue development in terms of avoiding infectious complications, positioning of implants and their fixation. Hernia is one of the widespread surgical pathologies as it is found in 4% of the population and its share among the inpatient surgical diseases is about 18-30%. Consequently annually up to 20-21 mln hernioplasties are carried out worldwide. Despite of many years of experience in the field of hernia surgical treatment there still exist many unsolved problems such as safe closure of defects of abdominal cavity wall. Up to 200 methods of hernioplastics, various implantations and application of synthetic materials refer to lack of the optimal surgical strategy. In modern herniology priorities are given to tension free plastics. The merge of the synthetic implants and "tension free hernioplastics" concepts enabled sharp reduction of the side effects list, making it possible to perform successful surgeries in that contingent whose treatment by the method of tissue-plasty was related with high risk of lethality. Large scale introduction of tension free hernioplastics caused intensification of the associated problems such as migration, dissection and shortening of the net.

Electrons, pseudoparticles, and quasiparticles in the one-dimensional many-electron problem

International Nuclear Information System (INIS)

Carmelo, J.M.; Castro Neto, A.H.

1996-01-01

We generalize the concept of quasiparticle for one-dimensional (1D) interacting electronic systems. The ↑ and ↓ quasiparticles recombine the pseudoparticle colors c and s (charge and spin at zero-magnetic field) and are constituted by one many-pseudoparticle topological-momentum shift and one or two pseudoparticles. These excitations cannot be separated. We consider the case of the Hubbard chain. We show that the low-energy electron-quasiparticle transformation has a singular character which justifies the perturbative and nonperturbative nature of the quantum problem in the pseudoparticle and electronic basis, respectively. This follows from the absence of zero-energy electron-quasiparticle overlap in 1D. The existence of Fermi-surface quasiparticles both in 1D and three dimensional (3D) many-electron systems suggests their existence in quantum liquids in dimensions 1 1 or whether it becomes finite as soon as we leave 1D remains an unsolved question. copyright 1996 The American Physical Society

Distance majorization and its applications.

Science.gov (United States)

Chi, Eric C; Zhou, Hua; Lange, Kenneth

2014-08-01

The problem of minimizing a continuously differentiable convex function over an intersection of closed convex sets is ubiquitous in applied mathematics. It is particularly interesting when it is easy to project onto each separate set, but nontrivial to project onto their intersection. Algorithms based on Newton's method such as the interior point method are viable for small to medium-scale problems. However, modern applications in statistics, engineering, and machine learning are posing problems with potentially tens of thousands of parameters or more. We revisit this convex programming problem and propose an algorithm that scales well with dimensionality. Our proposal is an instance of a sequential unconstrained minimization technique and revolves around three ideas: the majorization-minimization principle, the classical penalty method for constrained optimization, and quasi-Newton acceleration of fixed-point algorithms. The performance of our distance majorization algorithms is illustrated in several applications.

LAKE BAIKAL: Underwater neutrino detector

International Nuclear Information System (INIS)

Anon.

1991-01-01

A new underwater detector soon to be deployed in Lake Baikal in Siberia, the world's deepest lake with depths down to 1.7 kilometres, could help probe the deepest mysteries of physics. One of the big unsolved problems of astrophysics is the origin of very energetic cosmic rays. However there are many ideas on how particles could be accelerated by exotic concentrations of matter and provide the majority of the Galaxy's high energy particles. Clarification would come from new detectors picking up the energetic photons and neutrinos from these sources

Specific Reading Comprehension Disability: Major Problem, Myth, or Misnomer?

Science.gov (United States)

Spencer, Mercedes; Quinn, Jamie M.; Wagner, Richard K.

2014-01-01

The goal of the present study was to test three competing hypotheses about the nature of comprehension problems of students who are poor in reading comprehension. Participants in the study were first, second, and third graders, totaling nine cohorts and over 425,000 participants in all. The pattern of results was consistent across all cohorts:…

Nice or effective? Social problem solving strategies in patients with major depressive disorder.

Science.gov (United States)

Thoma, Patrizia; Schmidt, Tobias; Juckel, Georg; Norra, Christine; Suchan, Boris

2015-08-30

Our study addressed distinct aspects of social problem solving in 28 hospitalized patients with Major Depressive Disorder (MDD) and 28 matched healthy controls. Three scenario-based tests assessed the ability to infer the mental states of story characters in difficult interpersonal situations, the capacity to freely generate good strategies for dealing with such situations and the ability to identify the best solutions among less optimal alternatives. Also, standard tests assessing attention, memory, executive function and trait empathy were administered. Compared to controls, MDD patients showed impaired interpretation of other peoples' sarcastic remarks but not of the mental states underlying other peoples' actions. Furthermore, MDD patients generated fewer strategies that were socially sensitive and practically effective at the same time or at least only socially sensitive. Overall, while the free generation of adequate strategies for difficult social situations was impaired, recognition of optimal solutions among alternatives was spared in MDD patients. Higher generation scores were associated with higher trait empathy and cognitive flexibility scores. We suggest that this specific pattern of impairments ought to be considered in the development of therapies addressing impaired social skills in MDD. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Fluxes of radionuclides in agricultural environments: main results and still unsolved problems

International Nuclear Information System (INIS)

Alexakhin, R.; Firsakova, S.; Rauret, G.; Arkhipov, N.; Vandecasteele, C.M.; Ivanov, Y.; Fesenkow, S.; Sanzharova, N.

1996-01-01

Agricultural products originating from the areas subjected to high radioactive deposit after the Chernobyl accident are a main contributor to the radiological dose to local populations. The transfer fluxes of radionuclides through agricultural food chains, to food products consumed by humans, depend on the characteristics of t = = = = = = 37 Cs fluxes in the main agricultural ecosystems of the Chernobyl accident zone are quantitatively determined and the main topics, where further investigation is needed, are identified

HEALTH CARE INFORMATIZATION: PROBLEMS, SOLVED AND UNSOLVED. QUESTION OF EFFICIENCY AND SINGULARITY

Directory of Open Access Journals (Sweden)

О. P. Mintser

2013-11-01

Full Text Available The considered questions of transformation of basic presentation are in relation to health care informatization. One idea is postulated. Although from the moment of researches beginning in this direction passed more then 50 years, complete clarity in determination to the best strategy of informatization is not defined. New risks are marked. It's related with the origin of technological and informative singularity.

Some Unsolved Problems, Questions, and Applications of the Brightsen Nucleon Cluster Model

Directory of Open Access Journals (Sweden)

Smarandache F.

2010-04-01

Full Text Available Brightsen Model is opposite to the Standard Model, and it was build on John Weeler's Resonating Group Structure Model and on Linus Pauling's Close-Packed Spheron Model. Among Brightsen Model's predictions and applications we cite the fact that it derives the average number of prompt neutrons per fission event, it provides a theoretical way for understanding the low temperature / low energy reactions and for approaching the artificially induced fission, it predicts that forces within nucleon clusters are stronger than forces between such clusters within isotopes; it predicts the unmatter entities inside nuclei that result from stable and neutral union of matter and antimatter, and so on. But these predictions have to be tested in the future at the new CERN laboratory.

A LOOK AT SOME OF THE EUROPEAN UNION’S MAJOR SOCIAL PROBLEMS AND THEIR ECONOMIC IMPACT

Directory of Open Access Journals (Sweden)

Monika Moraliyska

2017-09-01

Full Text Available The EU's economy accounts for a significant share of the world economy. Measured in terms of GDP, it is still the biggest in the world. In addition to that, being a single market of 28 countries, the EU has been a major trading player accounting for around 20% of global exports and imports. However, EU’s trade was hit by the global recession. It is additionally hindered by the attempts of its economic policy to provide for a sustainable growth by investing in transport, energy and research in order to minimize the impact of further economic development on the environment. The most serious problems of the EU are connected with the unstable and comparatively low employment, continuing energy dependence, demographic change and population’s aging, as well as the persisting economic and social disparities within member states and between European regions in the North and South, West and East. The migration crisis adds to the problem with the lack of coherent solution, unsuccessful integration, growing inequalities and fragile multilateralism, having both – their social and economic effects. This paper aims to explore the most pressing challenges before the European Union’s economy today and in the years to come – aging population and social disparities.

Some solvable, and as yet unsolvable, polygon and walk models

International Nuclear Information System (INIS)

Guttmann, Anthony J

2006-01-01

One partly solvable and two solvable models of polygons are discussed. Using a simple transfer matrix approach Iwan Jensen has derived very long series expansions for the perimeter generating function of both three-choice polygons and punctured staircase polygons. In both cases it is found that all the terms in the generating function can be reproduced from a linear Fuchsian differential equation of order 8. We report on an analysis of the properties of the differential equations. Recently Enrica Duchi has discussed the problem of so-called prudent self-avoiding walks. We discuss the polygon analogue of this problem, and argue that the generating function for prudent polygons is unlikely to be differentiably finite, though a restricted version of the problem, called prudent polygons of the second type, is likely to be differentiably finite. The exact generating function for prudent polygons of the first type is also found

Security Measures to Protect Mobile Agents

Science.gov (United States)

Dadhich, Piyanka; Govil, M. C.; Dutta, Kamlesh

2010-11-01

The security issues of mobile agent systems have embarrassed its widespread implementation. Mobile agents that move around the network are not safe because the remote hosts that accommodate the agents initiates all kinds of attacks. These hosts try to analyze the agent's decision logic and their accumulated data. So, mobile agent security is the most challenging unsolved problems. The paper analyzes various security measures deeply. Security especially the attacks performed by hosts to the visiting mobile agent (the malicious hosts problem) is a major obstacle that prevents mobile agent technology from being widely adopted. Being the running environment for mobile agent, the host has full control over them and could easily perform many kinds of attacks against them.

On the Dirichlet problem for an elliptic equation

Directory of Open Access Journals (Sweden)

Anatolii K. Gushchin

2015-03-01

the boundary of a domain in which the problem is considered. The results about the solvability and about the boundary behavior of solutions are compared with the analogous theorems for classical and generalized solutions. Some unsolved problems arising from such comparison are discussed.

IYPT problems teach high school students about teamwork and the scientific method

Science.gov (United States)

Kochanski, K.; Klishin, A.

2015-12-01

Laboratory work is often STEM students' primary exposure to key creative and communicative skills in the sciences, including experimental design, trouble shooting, team work, and oral presentations. The International Young Physicists' Tournament (IYPT) teaches these skills by inviting high school students to investigate simple unsolved systems instead of reproducing familiar results. Students work in teams to form hypotheses, gather data, and present their results orally in a tournament format. The IYPT has published 17 questions yearly since 1988, and its archives are an efficient source of experimental problems for outreach programs and have also been used for first-year undergraduate project classes (Planisic, 2009). We present insights and outcomes from two schools in which we introduced a new extracurricular program based on the IYPT model. Twenty-four students worked in small teams for three hours per day for six weeks. Surprisingly, most teams chose problems in unfamiliar subject areas such as fluid dynamics, and tailored their approaches to take advantage of individual skills including soldering, photography, and theoretical analysis. As the program progressed, students developed an increasingly intuitive understanding of the scientific method. They began to discuss the repeatability of their experiments without prompting, and were increasingly willing to describe alternative hypotheses.

Optimal designs of mollusk shells from bivalves to snails.

Science.gov (United States)

Okabe, Takuya; Yoshimura, Jin

2017-02-10

Bivalve, ammonite and snail shells are described by a small number of geometrical parameters. Raup noted that the vast majority of theoretically possible shell forms do not occur in nature. The constraint factors that regulate the biased distribution of natural form have long since been an open problem in evolution. The problem of whether natural shell form is a result of optimization remains unsolved despite previous attempts. Here we solve this problem by considering the scaling exponent of shell thickness as a morphological parameter. The scaling exponent has a drastic effect on the optimal design of shell shapes. The observed characteristic shapes of natural shells are explained in a unified manner as a result of optimal utilization of shell material resources, while isometric growth in thickness leads to impossibly tight coiling.

Sampling Realistic Protein Conformations Using Local Structural Bias

DEFF Research Database (Denmark)

Hamelryck, Thomas Wim; Kent, John T.; Krogh, A.

2006-01-01

The prediction of protein structure from sequence remains a major unsolved problem in biology. The most successful protein structure prediction methods make use of a divide-and-conquer strategy to attack the problem: a conformational sampling method generates plausible candidate structures, which...... are subsequently accepted or rejected using an energy function. Conceptually, this often corresponds to separating local structural bias from the long-range interactions that stabilize the compact, native state. However, sampling protein conformations that are compatible with the local structural bias encoded...... in a given protein sequence is a long-standing open problem, especially in continuous space. We describe an elegant and mathematically rigorous method to do this, and show that it readily generates native-like protein conformations simply by enforcing compactness. Our results have far-reaching implications...

Type-Ia Supernova Rates and the Progenitor Problem: A Review

Science.gov (United States)

Maoz, D.; Mannucci, F.

2012-01-01

The identity of the progenitor systems of type-Ia supernovae (SNe Ia) is a major unsolved problem in astrophysics. SN Ia rates are providing some striking clues. We review the basics of SN rate measurement, preach about some sins of SN rate measurement and analysis, and illustrate one of these sins with an analogy about Martian scientists. We review the recent progress in measuring SN Ia rates in various environments and redshifts, and their use to reconstruct the SN Ia delay-time distribution (DTD) - the SN rate versus time that would follow a hypothetical brief burst of star formation. A good number of DTD measurements, using a variety of methods, appear to be converging. At delays 1measurements show a similar, ~t-1, power-law shape. The DTD peaks at the shortest delays probed. This result supports the idea of a double-degenerate progenitor origin for SNe Ia. Single-degenerate progenitors may still play a role in producing short-delay SNe Ia, or perhaps all SNe Ia, if the red-giant donor channel is more efficient than is found by most theoretical models. The DTD normalization enjoys fairly good agreement (though perhaps some tension), among the various measurements, with a Hubble time-integrated DTD value of about 2+/-1 SNe Ia per 1000Msolar (stellar mass formed with a low-mass turnover initial mass function). The local WD binary population suggests that the WD merger rate can explain the Galactic SN Ia rate, but only if sub-Chandra mergers lead to SN Ia events. We point to some future directions that should lead to progress in the field, including measurement of the bivariate (delay and stretch) SN Ia response function.

High vitamin B12 level and good treatment outcome may be associated in major depressive disorder

Directory of Open Access Journals (Sweden)

Tanskanen Antti

2003-12-01

Full Text Available Abstract Background Despite of an increasing body of research the associations between vitamin B12 and folate levels and the treatment outcome in depressive disorders are still unsolved. We therefore conducted this naturalistic prospective follow-up study. Our aim was to determine whether there were any associations between the vitamin B12 and folate level and the six-month treatment outcome in patients with major depressive disorder. Because vitamin B12 and folate deficiency may result in changes in haematological indices, including mean corpuscular volume, red blood cell count and hematocrit, we also examined whether these indices were associated with the treatment outcome. Methods Haematological indices, erythrocyte folate and serum vitamin B12 levels were determined in 115 outpatients with DSM-III-R major depressive disorder at baseline and serum vitamin B12 level again on six-month follow-up. The 17-item Hamilton Depression Rating Scale was also compiled, respectively. In the statistical analysis we used chi-squared test, Pearson's correlation coefficient, the Student's t-test, analysis of variance (ANOVA, and univariate and multivariate linear regression analysis. Results Higher vitamin B12 levels significantly associated with a better outcome. The association between the folate level and treatment outcome was weak and probably not independent. No relationship was found between haematological indices and the six-month outcome. Conclusion The vitamin B12 level and the probability of recovery from major depression may be positively associated. Nevertheless, further studies are suggested to confirm this finding.

Specific Reading Comprehension Disability: Major Problem, Myth, or Misnomer?

OpenAIRE

Spencer, Mercedes; Quinn, Jamie M.; Wagner, Richard K.

2014-01-01

The goal of the present study was to test three competing hypotheses about the nature of comprehension problems of students who are poor in reading comprehension. Participants in the study were first, second, and third graders, totaling 9 cohorts and over 425,000 participants in all. The pattern of results was consistent across all cohorts: Less than one percent of first- through third-grade students who scored as poor in reading comprehension were adequate in both decoding and vocabulary. Al...

Investigating the Conceptual Variation of Major Physics Textbooks

Science.gov (United States)

Stewart, John; Campbell, Richard; Clanton, Jessica

2008-04-01

The conceptual problem content of the electricity and magnetism chapters of seven major physics textbooks was investigated. The textbooks presented a total of 1600 conceptual electricity and magnetism problems. The solution to each problem was decomposed into its fundamental reasoning steps. These fundamental steps are, then, used to quantify the distribution of conceptual content among the set of topics common to the texts. The variation of the distribution of conceptual coverage within each text is studied. The variation between the major groupings of the textbooks (conceptual, algebra-based, and calculus-based) is also studied. A measure of the conceptual complexity of the problems in each text is presented.

Nucleon induced reactions

International Nuclear Information System (INIS)

Gmuca, S.; Antalik, R.; Kristiak, J.

1988-01-01

The collection contains full texts of 37 contributions; all fall within the INIS Subject Scope. The topics treated include some unsolved problems of nuclear reactions and relevant problems of nuclear structure at low and intermediate energies. (Z.S.)

Some functional equations originating from number theory

Indian Academy of Sciences (India)

R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

Moreover, we will also study some stability problems of those equations. ... Wisconsin in which he discussed a number of important unsolved problems [18]. ... According to a well-known theorem in number theory, a positive integer of the form.

Imaging of the major salivary glands

DEFF Research Database (Denmark)

Afzelius, Pia; Nielsen, Ming-Yuan; Ewertsen, Caroline

2016-01-01

The major salivary glands, submandibular, parotid and sublingual glands play an important role in preserving the oral cavity and dental health. Patients with problems of the major salivary glands may present with symptoms such as dry mouth, dysphagia and obstruction of duct, inflammation, severe...

EDITORIAL Road traffic accident: A major public health problem in ...

African Journals Online (AJOL)

admin

Damen Haile Mariam1. One of the articles in this issue demonstrates how road traffic accident is a serious, but neglected, health problem in Ethiopia using secondary data collected by the Amhara National Regional State. Police Commission from 2007-2011 (1). Fatalities due to traffic accidents are reported to be among.

Drug discovery for male subfertility using high-throughput screening: a new approach to an unsolved problem.

Science.gov (United States)

Martins da Silva, Sarah J; Brown, Sean G; Sutton, Keith; King, Louise V; Ruso, Halil; Gray, David W; Wyatt, Paul G; Kelly, Mark C; Barratt, Christopher L R; Hope, Anthony G

2017-05-01

in fluorescence in the primary screen were rescreened and evaluated further, resulting in 48 hit compounds that produced a concentration-dependent increase in [Ca2+]i. Sperm penetration studies confirmed in vitro exposure to two hit compounds (A and B) resulted in significant improvement in functional motility in spermatozoa from healthy volunteer donors (A: 1 cm penetration index 2.54, 2 cm penetration index 2.49; P < 0.005 and B: 1 cm penetration index 2.1, 2 cm penetration index 2.6; P < 0.005), but crucially, also in patient samples from those undergoing fertility treatment (A: 1 cm penetration index 2.4; P = 0.009, 2 cm penetration index 3.6; P = 0.02 and B: 1 cm penetration index 2.2; P = 0.0004, 2 cm penetration index 3.6; P = 0.002). This was primarily as a result of direct or indirect CatSper channel action, supported by evidence from electrophysiology studies of individual sperm. Increase and fluxes in [Ca2+]i are fundamental to the regulation of sperm motility and function, including acrosome reaction. The use of calcium signalling as a surrogate for sperm motility is acknowledged as a potential limitation in this study. We conclude that HTS can robustly, efficiently, identify novel compounds that increase [Ca2+]i in human spermatozoa and functionally modify motility, and propose its use as a cornerstone to build and transform much-needed drug discovery for male infertility. The majority of the data were obtained using funding from TENOVUS Scotland and Chief Scientist Office NRS Fellowship. Additional funding was provided by NHS Tayside, MRC project grants (MR/K013343/1, MR/012492/1) and University of Abertay. The authors declare that there is no conflict of interest. N/A. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology.

Boltzmann and Einstein: Statistics and dynamics – An unsolved ...

Indian Academy of Sciences (India)

classical macroscopic bodies in equilibrium in terms of the properties of the particles out of which they consist will ... librium velocity distribution function for point particles in free space to the very general case that a ... ics [9], solved the problem 'by cutting the Gordian knot' using a 'hypothesis of equal a priori probability for ...

On Frequency Combs in Monolithic Resonators

Science.gov (United States)

Savchenkov, A. A.; Matsko, A. B.; Maleki, L.

2016-06-01

Optical frequency combs have become indispensable in astronomical measurements, biological fingerprinting, optical metrology, and radio frequency photonic signal generation. Recently demonstrated microring resonator-based Kerr frequency combs point the way towards chip scale optical frequency comb generator retaining major properties of the lab scale devices. This technique is promising for integrated miniature radiofrequency and microwave sources, atomic clocks, optical references and femtosecond pulse generators. Here we present Kerr frequency comb development in a historical perspective emphasizing its similarities and differences with other physical phenomena. We elucidate fundamental principles and describe practical implementations of Kerr comb oscillators, highlighting associated solved and unsolved problems.

Interpersonal problems and impacts: further evidence for the role of interpersonal functioning in treatment outcome in major depressive disorder.

Science.gov (United States)

Quilty, Lena C; Mainland, Brian J; McBride, Carolina; Bagby, R Michael

2013-09-05

Empirical research has converged to support the concurrent association between social difficulties and psychiatric symptoms; yet, longitudinal associations between interpersonal problems and treatment outcome require clarification. The current investigation evaluated the influence of interpersonal problems assessed prior to treatment on interpersonal impacts assessed during treatment as well as on treatment outcome in outpatients with major depressive disorder (MDD). 125 participants with a primary diagnosis of MDD were randomized to receive cognitive behavioural therapy or interpersonal therapy. Participants completed the Beck Depression Inventory-II, Hamilton Depression Rating Scale, and Inventory of Interpersonal Problems Circumplex before and after treatment. Therapists completed the Impact Message Inventory during and after treatment. Interpersonal distress improved over the course of treatment; all other interpersonal changes were non-significant when distress was taken into account. Pre-treatment rigidity and agentic problems predicted less reduction in depressive symptoms, whereas agentic and communal impacts upon therapists during treatment predicted greater symptom change. Overall interpersonal distress was only indirectly associated with treatment response later in treatment, through its association with agentic style. Results did not differ across therapy type, and were replicated across self-report and interviewer-rated measures of depression severity. Limitations include the brief duration of treatment, lack of medication arm, and potentially restricted generalizability of patients in a randomized control trial to those in routine practice. Interpersonal style demonstrated a trait-like stability over treatment, and appears to fluctuate due to co-occurring distress. Yet, specific interpersonal styles were negative prognostic indicators, even within therapy specifically targeting interpersonal functioning. Copyright © 2013 Elsevier B.V. All rights

Cycles in graphs

CERN Document Server

Alspach, BR

1985-01-01

This volume deals with a variety of problems involving cycles in graphs and circuits in digraphs. Leading researchers in this area present here 3 survey papers and 42 papers containing new results. There is also a collection of unsolved problems.

Graphs, groups and surfaces

CERN Document Server

White, AT

1985-01-01

The field of topological graph theory has expanded greatly in the ten years since the first edition of this book appeared. The original nine chapters of this classic work have therefore been revised and updated. Six new chapters have been added, dealing with: voltage graphs, non-orientable imbeddings, block designs associated with graph imbeddings, hypergraph imbeddings, map automorphism groups and change ringing.Thirty-two new problems have been added to this new edition, so that there are now 181 in all; 22 of these have been designated as ``difficult'''' and 9 as ``unsolved''''. Three of the four unsolved problems from the first edition have been solved in the ten years between editions; they are now marked as ``difficult''''.

Applying physical science techniques and CERN technology to an unsolved problem in radiation treatment for cancer: the multidisciplinary 'VoxTox' research programme.

Science.gov (United States)

Burnet, Neil G; Scaife, Jessica E; Romanchikova, Marina; Thomas, Simon J; Bates, Amy M; Wong, Emma; Noble, David J; Shelley, Leila Ea; Bond, Simon J; Forman, Julia R; Hoole, Andrew Cf; Barnett, Gillian C; Brochu, Frederic M; Simmons, Michael Pd; Jena, Raj; Harrison, Karl; Yeap, Ping Lin; Drew, Amelia; Silvester, Emma; Elwood, Patrick; Pullen, Hannah; Sultana, Andrew; Seah, Shannon Yk; Wilson, Megan Z; Russell, Simon G; Benson, Richard J; Rimmer, Yvonne L; Jefferies, Sarah J; Taku, Nicolette; Gurnell, Mark; Powlson, Andrew S; Schönlieb, Carola-Bibiane; Cai, Xiaohao; Sutcliffe, Michael Pf; Parker, Michael A

2017-06-01

The VoxTox research programme has applied expertise from the physical sciences to the problem of radiotherapy toxicity, bringing together expertise from engineering, mathematics, high energy physics (including the Large Hadron Collider), medical physics and radiation oncology. In our initial cohort of 109 men treated with curative radiotherapy for prostate cancer, daily image guidance computed tomography (CT) scans have been used to calculate delivered dose to the rectum, as distinct from planned dose, using an automated approach. Clinical toxicity data have been collected, allowing us to address the hypothesis that delivered dose provides a better predictor of toxicity than planned dose.

Consciousness Regained: Disentangling Mechanisms, Brain Systems, and Behavioral Responses

NARCIS (Netherlands)

Storm, J.F.; Boly, M.; Casali, A.G.; Massimini, M.; Olcese, U.; Pennartz, C.M.A.; Wilke, M.

2017-01-01

How consciousness (experience) arises from and relates to material brain processes (the "mind-body problem") has been pondered by thinkers for centuries, and is regarded as among the deepest unsolved problems in science, with wide-ranging theoretical, clinical, and ethical implications. Until the

Crowdsourcing for Challenging Technical Problems - It Works!

Science.gov (United States)

Davis, Jeffrey R.

2011-01-01

The NASA Johnson Space Center Space Life Sciences Directorate (SLSD) and Wyle Integrated Science and Engineering (Wyle) will conduct a one-day business cluster at the 62nd IAC so that IAC attendees will understand the benefits of open innovation (crowdsourcing), review successful results of conducting technical challenges in various open innovation projects, and learn how an organization can effectively deploy these new problem solving tools to innovate more efficiently and effectively. Results from both the SLSD open innovation pilot program and the open innovation workshop conducted by the NASA Human Health and Performance Center will be discussed. NHHPC members will be recruited to participate in the business cluster (see membership http://nhhpc.nasa.gov) and as IAF members. Crowdsourcing may be defined as the act of outsourcing tasks that are traditionally performed by an employee or contractor to an undefined, generally large group of people or community (a crowd) in the form of an open call. The open call may be issued by the organization wishing to find a solution to a particular problem or complete a task, or by an open innovation service provider on behalf of that organization. In 2008, the SLSD, with the support of Wyle, established and implemented pilot projects in open innovation (crowdsourcing) to determine if these new internet-based platforms could indeed find solutions to difficult technical challenges. These unsolved technical problems were converted to problem statements, called Challenges by some open innovation service providers, and were then posted externally to seek solutions to these problems. In addition, an open call was issued internally to NASA employees Agency wide (11 Field Centers and NASA HQ) using an open innovation service provider crowdsourcing platform to post NASA challenges from each Center for the others to propose solutions). From 2008 to 2010, the SLSD issued 34 challenges, 14 externally and 20 internally. The 14 external

Continuous deep sedation and homicide: an unsolved problem in law and professional morality.

Science.gov (United States)

den Hartogh, Govert

2016-06-01

When a severely suffering dying patient is deeply sedated, and this sedated condition is meant to continue until his death, the doctor involved often decides to abstain from artificially administering fluids. For this dual procedure almost all guidelines require that the patient should not have a life expectancy beyond a stipulated maximum of days (4-14). The reason obviously is that in case of a longer life-expectancy the patient may die from dehydration rather than from his lethal illness. But no guideline tells us how we should describe the dual procedure in case of a longer life-expectancy. Many arguments have been advanced why we should not consider it to be a form of homicide, that is, ending the life of the patient (with or without his request). I argue that none of these arguments, taken separately or jointly, is persuasive. When a commission, even one that is not itself life-shortening, foreseeably renders a person unable to undo the life-shortening effects of another, simultaneous omission, the commission and the omission together should be acknowledged to kill her. I discuss the legal and ethical implications of this conclusion.

Do risk factors for problem behaviour act in a cumulative manner? An examination of ethnic minority and majority children through an ecological perspective.

Science.gov (United States)

Atzaba-Poria, Naama; Pike, Alison; Deater-Deckard, Kirby

2004-05-01

Extensive research has identified risk factors for problem behaviour in childhood. However, most of this research has focused on isolated variables, ignoring possible additive influences. The purpose of this study was to examine whether risk factors for problem behaviour act in a cumulative manner, and to investigate whether cumulative risk stemming from distinct ecological levels (Bronfenbrenner, 1979) differentially influences the manifestation of problem behaviours in middle childhood. In addition, ethnic differences between minority (i.e., Indian) and majority (i.e., English) families were examined. The sample consisted of 125 children (59 English and 66 of Indian origin) between the ages of 7 and 9.6 (M = 8.51, SD = 0.62) and their parents. Both mothers and fathers completed questionnaires regarding the children's problem behaviour and provided reports of the children's characteristics and environment. Children were also assessed and provided reports about themselves and their relationships. Finally, parent-child mutuality and parenting behaviour were coded from a videotaped parent-child interaction task. Risk factors acted in a cumulative manner - the more risk children experienced, the more problem behaviour they exhibited. Total problem behaviour was predicted by all three levels: individual, microsystem and exosystem. However, externalising problems were mainly predicted by microsystem-level cumulative risk, whereas internalising problems were predicted by both individual-level cumulative risk and exosystem-level cumulative risk. These results were similar for both ethnic groups. The support for the cumulative hypothesis highlights the importance of having a broad picture of children's characteristics and environmental components when analysing children's adjustment. The distinct influence of risk stemming from the different ecological levels suggests that the trajectories of internalising, externalising and total problem behaviour may be different.

IT Infrastructure Planning from a North Denmark Perspective: Major Problems, Consequences and Possible Solutions

DEFF Research Database (Denmark)

Knudsen, Thomas Phillip; Madsen, Ole Brun

2004-01-01

are proposed. These problems appear on the background of a dawning understanding of IT infrastructure as a crucial part of the modern society comparable to the recognised infrastructures, such as roads and electricity. The IT-infrastructure and the problems are placed in the context of the growing importance......This paper gives an overview of the more prominent problems in IT infrastructure evolution and in particular the neccessary planning process in Denmark. A discussion of consequences and possible solutions is presented. Through the DDN-project Nordjysk Netforum, NJNF, and its partners and attendant...... research at Aalborg University, AAU, it has become apparent that several problems pose significant hindrances to an efficient IT-infrastructrure planning and implementation. These problems range form awareness of IT-infrastructure issues, over education and research to main cause and possible solutions...

IT infrastructure planning from a North Denmark perspective: Major problems, consequences and possible solutions

DEFF Research Database (Denmark)

Madsen, Ole Brun; Knudsen, Thomas Phillip

are proposed. These problems appear on the background of a dawning understanding of IT infrastructure as a crucial part of the modern society comparable to the recognised infrastructures, such as roads and electricity. The IT-infrastructure and the problems are placed in the context of the growing importance......This paper gives an overview of the more prominent problems in IT infrastructure evolution and in particular the neccessary planning process in Denmark. A discussion of consequences and possible solutions is presented. Through the DDN-project Nordjysk Netforum, NJNF, and its partners and attendant...... research at Aalborg University, AAU, it has become apparent that several problems pose significant hindrances to an efficient IT-infrastructrure planning and implementation. These problems range form awareness of IT-infrastructure issues, over education and research to main cause and possible solutions...

Population Problem In Egypt As One of The Priority Health Problems ...

African Journals Online (AJOL)

In last decades, Egypt had suffered major socioeconomic consequences of population problem. This had resulted from the high levels of birth rates and the steady decline in death rates and so, a widened demographic gap. Management of population problem of Egypt included: Economic development, developing new ...

Ion-induced electron emission from clean metals

International Nuclear Information System (INIS)

Baragiola, R.A.; Alonso, E.V.; Ferron, J.; Oliva-Florio, A.; Universidad Nacional de Cuyo, San Carlos de Bariloche

1979-01-01

We report recent experimental work on electron emission from clean polycrystalline metal surfaces under ion bombardment. We critically discuss existing theories and point out the presently unsolved problems. (orig.)

Combined heat and power generation - a problem of reimbursement? CHP systems still on the march; BHKW - nur eine Frage der angemessenen Verguetung? Kraft-Waerme-Kopplung weiter im Aufwind

Energy Technology Data Exchange (ETDEWEB)

Jost, H.

1996-04-15

Systems for combined heat and power generation were a widely discussed issue in 1995. On the one hand, an ecological assessment was made by a study of the Eduard-Pestel-Institut fuer Systemforschung, Hanover. On the other hand, the problem of reimbursement for electricity supplied to the public grid is still unsolved. (orig.) [Deutsch] Anlagen zur gekoppelten Erzeugung von Strom (Kraft) und Waerme (KWK) waren im Jahr 1995 Gegenstand einer intensiven Diskussion. Zum einen hat eine Diskussion zur oekologischen Bewertung von KWK-Anlagen stattgefunden, die im wesentlichen von einer Studie des Eduard-Pestel-Instituts fuer Systemforschung in Hannover angestossen wurde. Zum anderen sind die Verguetungen fuer KWK-Strom in das oeffentliche Netz nach wie vor umstritten. (orig.)

Unsuccessfully Treated Hypertension: A Major Public Health Problem With a Potential Solution.

Science.gov (United States)

Furberg, Curt D; Sealey, Jean E; Blumenfeld, Jon D

2017-09-01

About one-half of all hypertensive adults do not have their blood pressure controlled. They are often prescribed medications that conform to national guidelines but they continue to have elevated blood pressure. This public health problem might be improved by applying plasma renin guided therapy. A contributor to the public health problem of unsuccessfully treated hypertension is that the circulating renin-angiotensin system (RAS) is not recognized in treatment guidelines as clinically relevant for the treatment of hypertension or as important as the body salt status for determining blood pressure levels. Another contributor to the problem is the lack of specificity in the package inserts for antihypertensive drugs. They do not specifically state under the heading "Indications" that RAS blockers are primarily most effective in hypertensive subjects with medium and high plasma renin levels; by contrast, natriuretic drugs are most effective in those with low plasma renin levels. Literature review. To address the problem of unsuccessfully treated hypertension, we recommend that the "Indications" section of package inserts for antihypertensive drugs be more specific. The primary indication for RAS blockers ought to be hypertension with medium and high plasma renin levels, and natriuretic agents for those with low plasma renin levels. Similar language ought to be added to treatment guidelines. Additionally, 3 other reasons for lack of blood pressure control also need to be addressed-failure to prescribe antihypertensive drugs to hypertensive subjects, failure of patients to fill prescriptions, and low drug adherence. © American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com

The Focusing Optics X-ray Solar Imager (FOXSI): Update & Second Launch Project

Data.gov (United States)

National Aeronautics and Space Administration — Particle acceleration in solar flares and its contribution to coronal heating are among the main  unsolved problems in heliophysics. Accelerated electrons in a...

Nuclear energy's dilemma: disposing of hazardous radioactive waste safely. Report to the congress

International Nuclear Information System (INIS)

1977-01-01

The unsolved problem of radioactive waste disposal threatens the future of nuclear power in the United States. Nuclear critics, the public, business leaders, and Government officials concur that a solution to the disposal problem is critical to the continued growth of nuclear energy. The Energy Research and Development Administration has begun a program to demonstrate by the mid-1980s the feasibility and safety of placing radioactive wastes in deep geological formations. GAO points out that not only has progress been negligible to date, but that future program goals are overly optimistic because the Energy Research and Development Administration faces many unsolved social, regulatory, and geological obstacles. GAO also discusses the progress and problems the Energy Research and Development Administration faces in managing its radioactive waste and how the Nuclear Regulatory Commission is handling the problem of large amounts of spent nuclear fuel now accumulating at nuclear power plants, and makes a number of recommendations for regulatory and program management changes

The patient perspective in research on major depression

Directory of Open Access Journals (Sweden)

Cuijpers Pim

2011-05-01

Full Text Available Abstract Although thousands of studies have examined the genetics, epidemiology, etiology, biology, treatment and prevention of major depressive disorder, we still lack very basic knowledge about what patients with depressive disorders need. Despite the thousands of studies that have been conducted on major depression and the hundreds of randomized trials that have examined the effects of treatments, many patients still do not know how to cope with the daily problems caused by depressive disorders. In this Commentary the need for more research on the perspectives of patients is described. This research should guide treatment studies as well as basic research much more than it currently does. This perpective is especially important to understand and solve the undertreatment of depression, one of the major problems in this area. Up to 50% of depressed patients do not seek treatment, resulting in huge avoidable disease burden and economic costs. In order to solve this problem we need a better understanding of the problems patients encounter in daily life, and what factors contribute to the reasons for seeking treatment or not. Research from the patients' perspective is also necessary to meet the currently unmet information needs of patients, including information about the nature and causes of depression, stigma, medication, treatment and coping with the daily problems of having depression.

ANALIZA BUGETULUI UNIUNII EUROPENE ÎN 2006 ŞI PERSPECTIVA ACESTUIA ÎN PERIOADA 2007 – 2013

Directory of Open Access Journals (Sweden)

Romeo Victor Ionescu

2006-05-01

Full Text Available European Union budget takes into consideration the transformations of European policy priorities. This paper reveals the EU budget for 2006, which represents a major step for redirecting the use of European expenses towards a knowledge-based economy. This paper also presents the allocation of the EU budget for the unsolved problems and the contradictions that still persist in an enlarged Community. The EU 2007-2013 financial perspective was adopted by the European Council on December 15th, 2005 and mainly refers to: the long-lasting development; preservation and management of natural resources; citizenship, freedom, security and justice; EU as a global partner; administration and compensations.

On Frequency Combs in Monolithic Resonators

Directory of Open Access Journals (Sweden)

Savchenkov A. A.

2016-06-01

Full Text Available Optical frequency combs have become indispensable in astronomical measurements, biological fingerprinting, optical metrology, and radio frequency photonic signal generation. Recently demonstrated microring resonator-based Kerr frequency combs point the way towards chip scale optical frequency comb generator retaining major properties of the lab scale devices. This technique is promising for integrated miniature radiofrequency and microwave sources, atomic clocks, optical references and femtosecond pulse generators. Here we present Kerr frequency comb development in a historical perspective emphasizing its similarities and differences with other physical phenomena. We elucidate fundamental principles and describe practical implementations of Kerr comb oscillators, highlighting associated solved and unsolved problems.

Addressing the minimum fleet problem in on-demand urban mobility.

Science.gov (United States)

Vazifeh, M M; Santi, P; Resta, G; Strogatz, S H; Ratti, C

2018-05-01

Information and communication technologies have opened the way to new solutions for urban mobility that provide better ways to match individuals with on-demand vehicles. However, a fundamental unsolved problem is how best to size and operate a fleet of vehicles, given a certain demand for personal mobility. Previous studies 1-5 either do not provide a scalable solution or require changes in human attitudes towards mobility. Here we provide a network-based solution to the following 'minimum fleet problem', given a collection of trips (specified by origin, destination and start time), of how to determine the minimum number of vehicles needed to serve all the trips without incurring any delay to the passengers. By introducing the notion of a 'vehicle-sharing network', we present an optimal computationally efficient solution to the problem, as well as a nearly optimal solution amenable to real-time implementation. We test both solutions on a dataset of 150 million taxi trips taken in the city of New York over one year 6 . The real-time implementation of the method with near-optimal service levels allows a 30 per cent reduction in fleet size compared to current taxi operation. Although constraints on driver availability and the existence of abnormal trip demands may lead to a relatively larger optimal value for the fleet size than that predicted here, the fleet size remains robust for a wide range of variations in historical trip demand. These predicted reductions in fleet size follow directly from a reorganization of taxi dispatching that could be implemented with a simple urban app; they do not assume ride sharing 7-9 , nor require changes to regulations, business models, or human attitudes towards mobility to become effective. Our results could become even more relevant in the years ahead as fleets of networked, self-driving cars become commonplace 10-14 .

Attributional processes in the learned helplessness paradigm: behavioral effects of global attributions.

Science.gov (United States)

Mikulincer, M

1986-12-01

Following the learned helplessness paradigm, I assessed in this study the effects of global and specific attributions for failure on the generalization of performance deficits in a dissimilar situation. Helplessness training consisted of experience with noncontingent failures on four cognitive discrimination problems attributed to either global or specific causes. Experiment 1 found that performance in a dissimilar situation was impaired following exposure to globally attributed failure. Experiment 2 examined the behavioral effects of the interaction between stable and global attributions of failure. Exposure to unsolvable problems resulted in reduced performance in a dissimilar situation only when failure was attributed to global and stable causes. Finally, Experiment 3 found that learned helplessness deficits were a product of the interaction of global and internal attribution. Performance deficits following unsolvable problems were recorded when failure was attributed to global and internal causes. Results were discussed in terms of the reformulated learned helplessness model.

TRANSCATHETER AORTIC VALVE IMPLANTATION. STATE OF THE PROBLEM AND PROSPECTS IN RUSSIA

Directory of Open Access Journals (Sweden)

T. E. Imaev

2015-01-01

Full Text Available Nowadays aortic stenosis is the most common valvular pathology in Europe and North America and its incidence increases with age. Long asymptomatic period, the duration of which varies in different patients, is the main clinical feature of this disease. In 80% of asymptomatic patients with the severe aortic stenosis the onset of clinical signs that significantly worsen the prognosis, occurs within the next 4 years. So, if two-year survival rate in asymptomatic period is at least 50%, a 5-year survival rate in patients with symptomatic aortic stenosis without surgery, according to some estimates, is reduced to 15%. Therefore, these patients do not have any alternative to surgery. At that, high risk of complications after surgery and perioperative mortality related to them are the most essential problems of surgical treatment of the aortic valve diseases in the setting of cardiopulmonary bypass. This was the decisive factor for the development of alternative methods of surgical correction of the aortic valve diseases. Indications and contraindications for transcatheter aortic valve implantation (TAVI, which is currently a "disruptive technology", are discussed. Different models of aortic valve prostheses, the use of which is confirmed by the available evidence, are considered. The most important unsolved problems of TAVI use in recent times are mentioned in brief. More than 300 TAVI procedures have been performed in Russia recently which definitely does not cover the actual needs.

TRANSCATHETER AORTIC VALVE IMPLANTATION. STATE OF THE PROBLEM AND PROSPECTS IN RUSSIA

Directory of Open Access Journals (Sweden)

T. E. Imaev

2015-09-01

Full Text Available Nowadays aortic stenosis is the most common valvular pathology in Europe and North America and its incidence increases with age. Long asymptomatic period, the duration of which varies in different patients, is the main clinical feature of this disease. In 80% of asymptomatic patients with the severe aortic stenosis the onset of clinical signs that significantly worsen the prognosis, occurs within the next 4 years. So, if two-year survival rate in asymptomatic period is at least 50%, a 5-year survival rate in patients with symptomatic aortic stenosis without surgery, according to some estimates, is reduced to 15%. Therefore, these patients do not have any alternative to surgery. At that, high risk of complications after surgery and perioperative mortality related to them are the most essential problems of surgical treatment of the aortic valve diseases in the setting of cardiopulmonary bypass. This was the decisive factor for the development of alternative methods of surgical correction of the aortic valve diseases. Indications and contraindications for transcatheter aortic valve implantation (TAVI, which is currently a "disruptive technology", are discussed. Different models of aortic valve prostheses, the use of which is confirmed by the available evidence, are considered. The most important unsolved problems of TAVI use in recent times are mentioned in brief. More than 300 TAVI procedures have been performed in Russia recently which definitely does not cover the actual needs.

Development of a Microbiology Course for Diverse Majors; Longitudinal Survey of the Use of Various Active, Problem-Based Learning Assignments

Directory of Open Access Journals (Sweden)

Diana R. Cundell

2009-12-01

Full Text Available Educators are increasingly being encouraged to use more active- and problem-based-learning techniques and assignments in the classroom to improve critical and analytical thinking skills. Active learning-based courses have been purported to be more time consuming than traditional lecture methods and for many instructors have therefore proven difficult to include in many one-semester science courses. To address this problem, a series of assignments was developed for use in a basic microbiology course involving sophomore-, junior-, and senior-level students from five different biology majors (environmental science, biology, biochemistry, premedicine, and physician assistant. Writing assignments included global, historical, and social themes for which a standardized grading format was established. Students also participated in a class debate in which the merits of the living microbial kingdoms were discussed, with only one kingdom being saved from an imaginary global catastrophe. Traditional lectures were facilitated by the use of a dedicated note packet developed by the instructor and specific for course content. Laboratories involved group analysis of mini-case history studies involving pathogenic microbes. Students’ perceptions of the subject were assessed using an exit questionnaire sent to 100 of the 174 students who had taken the course during the 5-year time period. The majority of the 64 students who responded were sophomores (78%, in keeping with the target audience, and their perception of the course’s challenge level was significantly higher (p < 0.03, 8.7 than their junior and senior counterparts (7.9. Students rated the most useful learning tools as case history studies (9.4 and the class debate (9.1, with the introduction of a dedicated microbiology links web page to the University website representing the sole component resulting in a statistically significant increase in students’ perceptions of the importance of the course (p

[Consequences of obesity in children and teenagers: a problem that requires attention].

Science.gov (United States)

Liria, Reyna

2012-01-01

Obesity is a worldwide pandemic and children are a vulnerable group. In America, it was estimated that in 2010, 15.2% of 18 year-old children could suffer from this. Obesity in children and teenagers has a negative impact on health and on the load of diseases at this stage of life, and later on in adulthood, having a negative impact on the economy of a country due to the rise of risks of chronic diseases, health expenses and indirect costs as a result of the disease. Peru is going through an epidemiological transition, with unsolved malnutrition problems and high child obesity rates (10% of children under five), thus being one of the countries with a higher increase of child obesity in recent years in Latin America. Childhood and adolescence are considered critical periods because eating habits and physical activity start at this point; and because most obese children and teenagers will maintain those habits until they reach adulthood. For this reason, it is essential to seek strategies and interventions that prevent overweight and obesity among children and teenagers in order to improve the health conditions of a country.

Junior High School Students’ Perception about Simple Environmental Problem as an Impact of Problem based Learning

Science.gov (United States)

Tapilouw, M. C.; Firman, H.; Redjeki, S.; Chandra, D. T.

2017-09-01

Environmental problem is a real problem that occur in student’s daily life. Junior high school students’ perception about environmental problem is interesting to be investigated. The major aim of this study is to explore junior high school students’ perception about environmental problems around them and ways to solve the problem. The subject of this study is 69 Junior High School Students from two Junior High School in Bandung. This study use two open ended question. The core of first question is environmental problem around them (near school or house). The core of second question is the way to prevent or to solve the problem. These two question are as an impact of problem based learning in science learning. There are two major findings in this study. The first finding, based on most students’ perception, plastic waste cause an environmental problem. The second finding, environmental awareness can be a solution to prevent environmental pollution. The third finding, most student can classify environmental pollution into land, water and air pollution. We can conclude that Junior High School Students see the environmental problem as a phenomenon and teacher can explore environmental problem to guide the way of preventing and resolving environmental problem.

The Elder Problem

Directory of Open Access Journals (Sweden)

John W. Elder

2017-03-01

Full Text Available This paper presents an autobiographical and biographical historical account of the genesis, evolution and resolution of the Elder Problem. It begins with John W. Elder and his autobiographical story leading to his groundbreaking work on natural convection at Cambridge in the 1960’s. His seminal work published in the Journal of Fluid Mechanics in 1967 became the basis for the modern benchmark of variable density flow simulators that we know today as “The Elder Problem”. There have been well known and major challenges with the Elder Problem model benchmark—notably the multiple solutions that were ultimately uncovered using different numerical models. Most recently, it has been shown that the multiple solutions are indeed physically realistic bifurcation solutions to the Elder Problem and not numerically spurious artefacts. The quandary of the Elder Problem has now been solved—a major scientific breakthrough for fluid mechanics and for numerical modelling. This paper—records, reflections, reminiscences, stories and anecdotes—is an historical autobiographical and biographical memoir. It is the personal story of the Elder Problem told by some of the key scientists who established and solved the Elder Problem. 2017 marks the 50 year anniversary of the classical work by John W. Elder published in Journal of Fluid Mechanics in 1967. This set the stage for this scientific story over some five decades. This paper is a celebration and commemoration of the life and times of John W. Elder, the problem named in his honour, and some of the key scientists who worked on, and ultimately solved, it.

Traumatic brain injury: caregivers' problems and needs.

Science.gov (United States)

Hassan, S T S; Khaw, W F; Rosna, A R; Husna, J

2011-01-01

Traumatic brain injury (TBI) is an increasingly major world health problem. This short review using the most pertinent articles on TBI caregiving problems and needs highlights the pressing issues. Articles focusing on both TBI-caregivers' problems and needs are rarely found, especially for developing countries. Most TBI-caregiving is done by family members, whose altered lives portend burden and stresses which add to the overwhelming demand of caring for the TBI-survivor. Lack of information, financial inadequacy, anxiety, distress, coping deficits, poor adaptability, inadequate knowledge and skills, and a poor support system comprise the major problems. Dysfunctional communication between caregivers and care-receivers has been little researched. The major needs are focused on health and rehabilitation information, financial advice and assistance, emotional and social support, and positive psychological encouragement. In time, health information needs may be met, but not emotional support. Information on TBI caregiving problems and unmet needs is critical to all relevant healthcare stakeholders.

Does chaos theory have major implications for philosophy of medicine?

Science.gov (United States)

Holm, S

2002-12-01

In the literature it is sometimes claimed that chaos theory, non-linear dynamics, and the theory of fractals have major implications for philosophy of medicine, especially for our analysis of the concept of disease and the concept of causation. This paper gives a brief introduction to the concepts underlying chaos theory and non-linear dynamics. It is then shown that chaos theory has only very minimal implications for the analysis of the concept of disease and the concept of causation, mainly because the mathematics of chaotic processes entail that these processes are fully deterministic. The practical unpredictability of chaotic processes, caused by their extreme sensitivity to initial conditions, may raise practical problems in diagnosis, prognosis, and treatment, but it raises no major theoretical problems. The relation between chaos theory and the problem of free will is discussed, and it is shown that chaos theory may remove the problem of predictability of decisions, but does not solve the problem of free will. Chaos theory may thus be very important for our understanding of physiological processes, and specific disease entities, without having any major implications for philosophy of medicine.

Materials problems associated with fusion reactor technology

International Nuclear Information System (INIS)

Dutton, R.

This paper outlines the principles of design and operation of conceptual fusion reactors, indicates the level of research funding and activity being proposed at major centres and reviews the major materials problems which have been identified, together with an outline of the experimental techniques which have been suggested for investigating these problems. (author)

Interpersonal psychotherapy (IPT) in major depressive disorder.

Science.gov (United States)

Brakemeier, Eva-Lotta; Frase, Lukas

2012-11-01

In this article, we will introduce interpersonal psychotherapy as an effective short-term treatment strategy in major depression. In IPT, a reciprocal relationship between interpersonal problems and depressive symptoms is regarded as important in the onset and as a maintaining factor of depressive disorders. Therefore, interpersonal problems are the main therapeutic targets of this approach. Four interpersonal problem areas are defined, which include interpersonal role disputes, role transitions, complicated bereavement, and interpersonal deficits. Patients are helped to break the interactions between depressive symptoms and their individual interpersonal difficulties. The goals are to achieve a reduction in depressive symptoms and an improvement in interpersonal functioning through improved communication, expression of affect, and proactive engagement with the current interpersonal network. The efficacy of this focused and structured psychotherapy in the treatment of acute unipolar major depressive disorder is summarized. This article outlines the background of interpersonal psychotherapy, the process of therapy, efficacy, and the expansion of the evidence base to different subgroups of depressed patients.

Gamification for Non-Majors Mathematics: An Innovative Assignment Model

Science.gov (United States)

Leong, Siow Hoo; Tang, Howe Eng

2017-01-01

The most important ingredient of the pedagogy for teaching non-majors is getting their engagement. This paper proposes to use gamification to engage non-majors. An innovative game termed as Cover the Hungarian's Zeros is designed to tackle the common weakness of non-majors mathematics in solving the assignment problem using the Hungarian Method.…

Researching consumers' attitudes: Some difficulties, problems and dilemmas

Directory of Open Access Journals (Sweden)

Gutić Dragutin

2010-01-01

Full Text Available Consumers' attitudes have always had a central place in marketing theory and practice. There is a great number of different problems, difficulties and dilemmas, which come from different sources and have different content, and which very often arise as a stumbling block in researching consumers' attitudes. Part of them is already contained in different views on term attitudes itself. The second part lies in an unsolved puzzle of consumers' attitudes and behaviour relation. The third part is of methodological nature in research. The fourth is in usage of different, numerous techniques that researchers have at their disposal when researching attitudes. It might sound unbelievable, but since the 1960s till today, very few researchers have understood, and knew real nature of the term, essence and meaning of attitudes in marketing. There is even less of them who know how to examine attitudes and generally use adequately and productively. Attitudes belong to the most complex psychical processes. The complexity of attitudes is manifesting during the research. It is not a rarity to become convinced that important contents, such as: determining dimensions, components, sources of emerging and stability of researched attitudes are not present in attitudes' examination and research. In most cases, research results of consumers' attitudes are actually nothing more than statements about the existence of positive and negative attitudes. There is still no complex method that can be used in research. Different, essentially partial methods are being used instead, usually to investigate particular components and dimensions of consumers' attitudes. There are more groups of problems that appear in consumers' attitudes examination. For this occasion, we point out three: problems that result from lack of knowledge and not adequate understanding of attitudes; problems related to level of examinee's (consumer's consciousness of his attitude; problems emerging from

Particle-in-cell modeling of streamer branching in CO2 gas

KAUST Repository

Levko, Dmitry; Pachuilo, Michael; Raja, Laxminarayan L

2017-01-01

The mechanism of streamer branching remains one of the unsolved problems of low-temperature plasma physics. The understanding of this phenomenon requires very high-fidelity models that include, for instance, the kinetic description of electrons

The Problem of Evil

OpenAIRE

Araki,Naoki

2018-01-01

The Problem of Evil has been discussed as one of the major problems in monotheism. “Why does Almighty God allow evil to exist?” Various solutions to this problem have been proposed, including the Free Will Defence. But none of them is convincing. The Problem of Evil has an assumption, which is that God exists. One of the proofs of God’s existence is René Descartes’s Ontological Argument. But none of them is persuasive. Every logic has its own assumption, which needs to be verified. So this pr...

A linear programming model for protein inference problem in shotgun proteomics.

Science.gov (United States)

Huang, Ting; He, Zengyou

2012-11-15

Assembling peptides identified from tandem mass spectra into a list of proteins, referred to as protein inference, is an important issue in shotgun proteomics. The objective of protein inference is to find a subset of proteins that are truly present in the sample. Although many methods have been proposed for protein inference, several issues such as peptide degeneracy still remain unsolved. In this article, we present a linear programming model for protein inference. In this model, we use a transformation of the joint probability that each peptide/protein pair is present in the sample as the variable. Then, both the peptide probability and protein probability can be expressed as a formula in terms of the linear combination of these variables. Based on this simple fact, the protein inference problem is formulated as an optimization problem: minimize the number of proteins with non-zero probabilities under the constraint that the difference between the calculated peptide probability and the peptide probability generated from peptide identification algorithms should be less than some threshold. This model addresses the peptide degeneracy issue by forcing some joint probability variables involving degenerate peptides to be zero in a rigorous manner. The corresponding inference algorithm is named as ProteinLP. We test the performance of ProteinLP on six datasets. Experimental results show that our method is competitive with the state-of-the-art protein inference algorithms. The source code of our algorithm is available at: https://sourceforge.net/projects/prolp/. zyhe@dlut.edu.cn. Supplementary data are available at Bioinformatics Online.

The RNA World as a Model System to Study the Origin of Life.

Science.gov (United States)

Pressman, Abe; Blanco, Celia; Chen, Irene A

2015-10-05

Understanding how life arose is a fundamental problem of biology. Much progress has been made by adopting a synthetic and mechanistic perspective on originating life. We present a current view of the biochemistry of the origin of life, focusing on issues surrounding the emergence of an RNA World in which RNA dominated informational and functional roles. There is cause for optimism on this difficult problem: the prebiotic chemical inventory may not have been as nightmarishly complex as previously thought; the catalytic repertoire of ribozymes continues to expand, approaching the goal of self-replicating RNA; encapsulation in protocells provides evolutionary and biophysical advantages. Nevertheless, major issues remain unsolved, such as the origin of a genetic code. Attention to this field is particularly timely given the accelerating discovery and characterization of exoplanets. Copyright © 2015 Elsevier Ltd. All rights reserved.

Goats display audience-dependent human-directed gazing behaviour in a problem-solving task.

Science.gov (United States)

Nawroth, Christian; Brett, Jemma M; McElligott, Alan G

2016-07-01

Domestication is an important factor driving changes in animal cognition and behaviour. In particular, the capacity of dogs to communicate in a referential and intentional way with humans is considered a key outcome of how domestication as a companion animal shaped the canid brain. However, the lack of comparison with other domestic animals makes general conclusions about how domestication has affected these important cognitive features difficult. We investigated human-directed behaviour in an 'unsolvable problem' task in a domestic, but non-companion species: goats. During the test, goats experienced a forward-facing or an away-facing person. They gazed towards the forward-facing person earlier and for longer and showed more gaze alternations and a lower latency until the first gaze alternation when the person was forward-facing. Our results provide strong evidence for audience-dependent human-directed visual orienting behaviour in a species that was domesticated primarily for production, and show similarities with the referential and intentional communicative behaviour exhibited by domestic companion animals such as dogs and horses. This indicates that domestication has a much broader impact on heterospecific communication than previously believed. © 2016 The Author(s).

Major Thought Restructuring: The Roles of Different Prefrontal Cortical Regions.

Science.gov (United States)

Seyed-Allaei, Shima; Avanaki, Zahra Nasiri; Bahrami, Bahador; Shallice, Tim

2017-07-01

An important question for understanding the neural basis of problem solving is whether the regions of human prefrontal cortices play qualitatively different roles in the major cognitive restructuring required to solve difficult problems. However, investigating this question using neuroimaging faces a major dilemma: either the problems do not require major cognitive restructuring, or if they do, the restructuring typically happens once, rendering repeated measurements of the critical mental process impossible. To circumvent these problems, young adult participants were challenged with a one-dimensional Subtraction (or Nim) problem [Bouton, C. L. Nim, a game with a complete mathematical theory. The Annals of Mathematics, 3, 35-39, 1901] that can be tackled using two possible strategies. One, often used initially, is effortful, slow, and error-prone, whereas the abstract solution, once achieved, is easier, quicker, and more accurate. Behaviorally, success was strongly correlated with sex. Using voxel-based morphometry analysis controlling for sex, we found that participants who found the more abstract strategy (i.e., Solvers) had more gray matter volume in the anterior medial, ventrolateral prefrontal, and parietal cortices compared with those who never switched from the initial effortful strategy (i.e., Explorers). Removing the sex covariate showed higher gray matter volume in Solvers (vs. Explorers) in the right ventrolateral prefrontal and left parietal cortex.

Traumatic Brain Injury: Caregivers’ Problems and Needs

Directory of Open Access Journals (Sweden)

syed tajjudin syed hassan

2011-03-01

Full Text Available Traumatic brain injury (TBI is an increasingly major world health problem. This short review using the most pertinent articles on TBI caregiving problems and needs highlights the pressing issues. Articles focusing on both TBI-caregivers’ problems and needs are rarely found, especially for developing countries. Most TBI-caregiving is done by family members, whose altered lives portend burden and stresses which add to the overwhelming demand of caring for the TBI-survivor. Lack of information, fi nancial inadequacy, anxiety, distress, coping defi cits, poor adaptability, inadequate knowledge and skills, and a poor support system comprise the major problems. Dysfunctional communication between caregivers and care-receivers has been little researched. The major needs are focused on health and rehabilitation information, fi nancial advice and assistance, emotional and social support, and positive psychological encouragement. In time, health information needs may be met, but not emotional support. Information on TBI caregiving problems and unmet needs is critical to all relevant healthcare stakeholders. Keywords: caregivers, rehabilitation, traumatic brain injury

Epidemiology of major depressive disorder

NARCIS (Netherlands)

Stegenga, B.T.

2011-01-01

Major depressive disorder (MDD) is a serious health problem and will be the second leading cause of burden of disease worldwide by 2030. To be able to prevent MDD, insight into risk factors for the onset of MDD is of clear importance. On the other hand, if onset of MDD has occurred, one may argue

Navigational potential of e-vector sensing by marine animals

Science.gov (United States)

Waterman, Talbot H.

1993-02-01

This essay documents an informal talk about the central theme in the author's research career. That has mainly related to the visual physiology and orientation of aquatic animals, particularly with regard to underwater polarized light. This required pioneer measurements of underwater polarized light patterns, proof that oriented behavior could be determined by e- vector direction independently of intensity patterns or other secondary clues and a demonstration of the retinal dichroic mechanism involved, at least in crustacean compound eyes. The relevant visual data processing by two orthogonal channels was also analyzed with regard to oriented swimming behavior. Some current research by others and major unsolved problems are mentioned and the relevant part of the author's bibliography is appended.

Early Death in Two Patients with Acute Promyelocytic Leukemia Presenting the bcr3 Isoform, FLT3-ITD Mutation, and Elevated WT1 Level

Directory of Open Access Journals (Sweden)

Marianna Greco

2013-01-01

Full Text Available Despite major advances in the treatment of acute promyelocytic leukemia (APL, the problem of early death (ED remains unsolved. Alongside the currently known clinical and hematological risk factors, prognostic significance has been attributed to internal tandem duplication mutations of the fms-like tyrosine kinase-3 (FLT3-ITD, hypogranular variant morphology, and the bcr-3 isoform of PML-RARα. We describe premature death of two patients with the hypogranular variant of APL who presented remarkably high expression levels of Wilms' tumor gene (WT1. Our results point to WT1 as an important prognostic factor of ED that needs to be promptly evaluated in all newly diagnosed cases of APL.

[Conversations on the "good death": the bioethical debate on euthanasia].

Science.gov (United States)

Siqueira-Batista, Rodrigo; Schramm, Fermin Roland

2005-01-01

Despite extensive current debate on euthanasia, many open and apparently unsolvable issues persist, awaiting a better conceptual treatment. The area includes "prejudices and fundamentalisms" in relation to the theme, still viewed as taboo by a major share of society, specifically in the case of Brazil, while semantic imprecision in the term and argumentative tensions surround the issue, focusing on the principles of sacredness of life, quality of life, and autonomy and the so-called "slippery slope" argument. The purpose of the current essay is thus to serve as a sphere of inquiry concerning euthanasia, moving from historical antecedents towards a better solution to the problem and the demarcation of necessary future perspectives for enhanced understanding of the issue.

10-Year Strategic Vision: Forging the Future of the DOE JGI

Energy Technology Data Exchange (ETDEWEB)

None

2012-09-01

Dramatic technological advances in genomics continue to transform modern biology. The DOE Joint Genome Institute (DOE JGI) has been at the leading edge of large-scale sequence-based science from its inception. Presently our ability to generate genomic data greatly outpaces our capacity to convert these data into biological insights. Bridging the gap between a sequenced genome and understanding of organism-scale functions is a significant unsolved problem in modern biology. Consequently, as the DOE JGI plans for its future, a major objective is to couple the generation of sequence data with the development of new large-scale experimental and computational capabilities to functionally annotate DNA sequences, thereby narrowing the gap between generation and interpretation of sequence data.

Black hole formation in perfect fluid collapse

International Nuclear Information System (INIS)

Goswami, Rituparno; Joshi, Pankaj S

2004-01-01

We construct here a special class of perfect fluid collapse models which generalizes the homogeneous dust collapse solution in order to include nonzero pressures and inhomogeneities into evolution. It is shown that a black hole is necessarily generated as the end product of continued gravitational collapse, rather than a naked singularity. We examine the nature of the central singularity forming as a result of endless collapse and it is shown that no nonspacelike trajectories can escape from the central singularity. Our results provide some insights into how the dynamical collapse works and into the possible formulations of the cosmic censorship hypothesis, which is as yet a major unsolved problem in black hole physics

Case of Two Electrostatics Problems: Can Providing a Diagram Adversely Impact Introductory Physics Students' Problem Solving Performance?

Science.gov (United States)

Maries, Alexandru; Singh, Chandralekha

2018-01-01

Drawing appropriate diagrams is a useful problem solving heuristic that can transform a problem into a representation that is easier to exploit for solving it. One major focus while helping introductory physics students learn effective problem solving is to help them understand that drawing diagrams can facilitate problem solution. We conducted an…

Eldercare at Home: Vision Problems

Science.gov (United States)

... seeing close objects or reading small print. Many things can be done to help with these vision problems. Using reading ... t Working If vision problems seem to be getting worse and are of major concern to the ... what the results have been. Related Resources ...

Ontogenetic effects on gazing behaviour: a case study of kennel dogs (Labrador Retrievers) in the impossible task paradigm.

Science.gov (United States)

D'Aniello, Biagio; Scandurra, Anna

2016-05-01

Life experiences and living conditions can influence the problem-solving strategies and the communicative abilities of dogs with humans. The goals of this study were to determine any behavioural differences between Labrador Retrievers living in a kennel and those living in a house as pets and to assess whether kennel dogs show preferences in social behaviours for their caretaker relative to a stranger when they are faced with an unsolvable task. Nine Labrador Retrievers living in a kennel from birth and ten Labrador Retrievers living in a family as pets were tested. The experimental procedure consisted of three "solvable" tasks in which the dogs could easily retrieve food from a container followed by an "unsolvable" task in which the container was hermetically locked. Dogs of both groups spent the same amount of time interacting with the experimental apparatus. Kennel dogs gazed towards people for less time and with higher latency than pet dogs; however, there were no significant preferences in gazing towards the stranger versus the caretaker in both groups. These findings demonstrated that kennel dogs are less prone to use human-directed gazing behaviour when they are faced with an unsolvable problem, taking the humans into account to solve a task less than do the pet dogs.

Reading problems and major mental disorders - co-occurrences and familial overlaps in a Swedish nationwide cohort.

Science.gov (United States)

Cederlöf, Martin; Maughan, Barbara; Larsson, Henrik; D'Onofrio, Brian M; Plomin, Robert

2017-08-01

Reading problems often co-occur with ADHD and conduct disorder. However, the patterns of co-occurrence and familial overlap between reading problems and other psychiatric disorders have not been systematically explored. We conducted a register-based cohort study including 8719 individuals with reading problems and their siblings, along with matched comparison individuals. Conditional logistic regressions estimated risks for ADHD, autism, obsessive-compulsive disorder, anorexia nervosa, schizophrenia, bipolar disorder, depression, substance use disorder, and violent/non-violent criminality in individuals with reading problems and their siblings. Diagnoses of psychiatric disorders were physician-assigned and ascertained from the Swedish National Patient Register, and crime convictions from the Swedish National Crime Register. We found that individuals with reading problems had excess risks for all psychiatric disorders (except anorexia nervosa) and criminality, with risk ratios between 1.34 and 4.91. Siblings of individuals with reading problems showed excess risks for ADHD, autism, schizophrenia, bipolar disorder, depression, substance use disorder, and non-violent criminality, with risk ratios between 1.14 and 1.70. In summary, individuals with reading problems had increased risks of virtually all psychiatric disorders, and criminality. The origin of most of these overlaps was familial, in that siblings of individuals with reading problems also had elevated risks of ADHD, autism, schizophrenia, bipolar disorder, depression, substance use disorder, and non-violent criminality. These findings have implications for gene-searching efforts, and suggest that health care practitioners should be alert for signs of psychiatric disorders in families where reading problems exist. Copyright © 2017 Elsevier Ltd. All rights reserved.

Anaplastology in times of facial transplantation: Still a reasonable treatment option?

Science.gov (United States)

Toso, Sabine Maria; Menzel, Kerstin; Motzkus, Yvonne; Klein, Martin; Menneking, Horst; Raguse, Jan-Dirk; Nahles, Susanne; Hoffmeister, Bodo; Adolphs, Nicolai

2015-09-01

Optimum functional and aesthetic facial reconstruction is still a challenge in patients who suffer from inborn or acquired facial deformity. It is known that functional and aesthetic impairment can result in significant psychosocial strain, leading to the social isolation of patients who are affected by major facial deformities. Microvascular techniques and increasing experience in facial transplantation certainly contribute to better restorative outcomes. However, these technologies also have some drawbacks, limitations and unsolved problems. Extensive facial defects which include several aesthetic units and dentition can be restored by combining dental prostheses and anaplastology, thus providing an adequate functional and aesthetic outcome in selected patients without the drawbacks of major surgical procedures. Referring to some representative patient cases, it is shown how extreme facial disfigurement after oncological surgery can be palliated by combining intraoral dentures with extraoral facial prostheses using individualized treatment and without the need for major reconstructive surgery. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Organizational structures in Collaborative Work Environments: the return of the matrix?

NARCIS (Netherlands)

Guldemond, E.; Have, K. ten; Knoppe, R.

2010-01-01

After major petroleum companies successfully implemented the hardware, tools and applications in Collaborative Work Environments (CWE), human factor issues remain unsolved. Working in these Collaborative Work Environments cuts across traditional disciplinary and geographically dispersed boundaries.

Consequences of Learned Helplessness and Recognition of the State of Cognitive Exhaustion in Persons with Mild Intellectual Disability.

Science.gov (United States)

Gacek, Michał; Smoleń, Tomasz; Pilecka, Władysława

2017-01-01

Persons with intellectual disability are a group at risk of being exposed to overly demanding problem-solving situations, which may produce learned helplessness . The research was based on the informational model of learned helplessness. The consequences of exposure to an unsolvable task and the ability to recognize the symptoms of cognitive exhaustion were tested in 120 students with mild intellectual disability. After the exposure to the unsolvable task, persons in the experimental group obtained lower results than the control group in the escape/avoidance learning task, but a similar result was found in the divergent thinking fluency task. Also, participants in the experimental group had difficulties recognizing the symptoms of the cognitive exhaustion state. After a week's time, the difference in escape/avoidance learning performance was still observed. The results indicate that exposure to unsolvable tasks may negatively influence the cognitive performance in persons with intellectual disability, although those persons may not identify the cognitive state related to lowered performance.

Dynamic range majority data structures

DEFF Research Database (Denmark)

Elmasry, Amr Ahmed Abd Elmoneim; He, Meng; Munro, J. Ian

2011-01-01

Given a set P of n coloured points on the real line, we study the problem of answering range α-majority (or "heavy hitter") queries on P. More specifically, for a query range Q, we want to return each colour that is assigned to more than an α-fraction of the points contained in Q. We present a ne...

Field Response Prediction: Framing the problem.

Energy Technology Data Exchange (ETDEWEB)

Cabrera-Palmer, Belkis [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-06-01

Predicting the performance of radiation detection systems at field sites based on measured performance acquired under controlled conditions at test locations, e.g., the Nevada National Security Site (NNSS), remains an unsolved and standing issue within DNDO’s testing methodology. Detector performance can be defined in terms of the system’s ability to detect and/or identify a given source or set of sources, and depends on the signal generated by the detector for the given measurement configuration (i.e., source strength, distance, time, surrounding materials, etc.) and on the quality of the detection algorithm. Detector performance is usually evaluated in the performance and operational testing phases, where the measurement configurations are selected to represent radiation source and background configurations of interest to security applications.

Model-based prediction of nephropathia epidemica outbreaks based on climatological and vegetation data and bank vole population dynamics

NARCIS (Netherlands)

Amirpour Haredasht, S.; Taylor, J.C.; Maes, P.; Verstraeten, W.W.; Clement, J.; Barrios, M.; Lagrou, K.; Van Ranst, M.; Coppin, P.; Berckmans, D.; Aerts, J.M.

2013-01-01

Wildlife-originated zoonotic diseases in general are a major contributor to emerging infectious diseases. Hantaviruses more specifically cause thousands of human disease cases annually worldwide, while understanding and predicting human hantavirus epidemics pose numerous unsolved challenges.

Sequelae of Endoscopic Inguinal Hernia Repair : Incidence, evaluation and management

NARCIS (Netherlands)

Burgmans, J.P.J.

2015-01-01

The endoscopic preperitoneal technique (TEP) is an appealing inguinal hernia repair technique, theoretically superior to other approaches. In practice some problems remain unsolved. Real incidences of chronic postoperative inguinal pain (CPIP) and other important sequelae of endoscopic hernia repair

The internal percolation problem

International Nuclear Information System (INIS)

Bezsudnov, I.V.; Snarskii, A.A.

2010-01-01

The internal percolation problem (IP) as a new type of the percolation problem is introduced and investigated. In spite of the usual (or external) percolation problem (EP) when the percolation current flows from the top to the bottom of the system, in IP case the voltage is applied through bars which are present in the hole located within the system. The EP problem has two major parameters: M-size of the system and a 0 -size of inclusions, bond size, etc. The IP problem holds one parameter more: size of the hole L. Numerical simulation shows that the critical indexes of conductance for the IP problem are very close to those in the EP problem. On the contrary, the indexes of the relative spectral noise density of 1/f noise and higher moments differ from those in the EP problem. The basics of these facts is discussed.

Recursive Monte Carlo method for deep-penetration problems

International Nuclear Information System (INIS)

Goldstein, M.; Greenspan, E.

1980-01-01

The Recursive Monte Carlo (RMC) method developed for estimating importance function distributions in deep-penetration problems is described. Unique features of the method, including the ability to infer the importance function distribution pertaining to many detectors from, essentially, a single M.C. run and the ability to use the history tape created for a representative region to calculate the importance function in identical regions, are illustrated. The RMC method is applied to the solution of two realistic deep-penetration problems - a concrete shield problem and a Tokamak major penetration problem. It is found that the RMC method can provide the importance function distributions, required for importance sampling, with accuracy that is suitable for an efficient solution of the deep-penetration problems considered. The use of the RMC method improved, by one to three orders of magnitude, the solution efficiency of the two deep-penetration problems considered: a concrete shield problem and a Tokamak major penetration problem. 8 figures, 4 tables

Biomedical informatics discovering knowledge in big data

CERN Document Server

Holzinger, Andreas

2014-01-01

This book provides a broad overview of the topic Bioinformatics (medical informatics + biological information) with a focus on data, information and knowledge. From data acquisition and storage to visualization, privacy, regulatory, and other practical and theoretical topics, the author touches on several fundamental aspects of the innovative interface between the medical and computational domains that form biomedical informatics. Each chapter starts by providing a useful inventory of definitions and commonly used acronyms for each topic, and throughout the text, the reader finds several real-world examples, methodologies, and ideas that complement the technical and theoretical background. Also at the beginning of each chapter a new section called "key problems", has been added, where the author discusses possible traps and unsolvable or major problems. This new edition includes new sections at the end of each chapter, called "future outlook and research avenues," providing pointers to future challenges.

The association of minor and major depression with health problem-solving and diabetes self-care activities in a clinic-based population of adults with type 2 diabetes mellitus.

Science.gov (United States)

Shin, Na; Hill-Briggs, Felicia; Langan, Susan; Payne, Jennifer L; Lyketsos, Constantine; Golden, Sherita Hill

2017-05-01

We examined whether problem-solving and diabetes self-management behaviors differ by depression diagnosis - major depressive disorder (MDD) and minor depressive disorder (MinDD) - in adults with Type 2 diabetes (T2DM). We screened a clinical sample of 702 adults with T2DM for depression, identified 52 positive and a sample of 51 negative individuals, and performed a structured diagnostic psychiatric interview. MDD (n=24), MinDD (n=17), and no depression (n=62) were diagnosed using Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) Text Revised criteria. Health Problem-Solving Scale (HPSS) and Summary of Diabetes Self-Care Activities (SDSCA) questionnaires determined problem-solving and T2DM self-management skills, respectively. We compared HPSS and SDSCA scores by depression diagnosis, adjusting for age, sex, race, and diabetes duration, using linear regression. Total HPSS scores for MDD (β=-4.38; pdepression. Total SDSCA score for MDD (β=-10.1; pdepression, and was partially explained by total HPSS. MinDD and MDD individuals with T2DM have impaired problem-solving ability. MDD individuals had impaired diabetes self-management, partially explained by impaired problem-solving. Future studies should assess problem-solving therapy to treat T2DM and MinDD and integrated problem-solving with diabetes self-management for those with T2DM and MDD. Copyright © 2017 Elsevier Inc. All rights reserved.

Students' Problem Solving and Justification

Science.gov (United States)

Glass, Barbara; Maher, Carolyn A.

2004-01-01

This paper reports on methods of students' justifications of their solution to a problem in the area of combinatorics. From the analysis of the problem solving of 150 students in a variety of settings from high-school to graduate study, four major forms of reasoning evolved: (1) Justification by Cases, (2) Inductive Argument, (3) Elimination…

Exploring the role of conceptual scaffolding in solving synthesis problems

Directory of Open Access Journals (Sweden)

Lin Ding1,*

2011-10-01

Full Text Available It is well documented that when solving problems experts first search for underlying concepts while students tend to look for equations and previously worked examples. The overwhelming majority of end-of-chapter (EOC problems in most introductory physics textbooks contain only material and examples discussed in a single chapter, rarely requiring a solver to conduct a general search for underlying concepts. Hypothesizing that complete reliance on EOC problems trains students to rely on a nonexpert approach, we designed and implemented “synthesis” problems, each combining two major concepts that are broadly separated in the teaching timeline. To provide students with guided conceptual scaffolding, we encapsulated each synthesis problem into a sequence with two preceding conceptually based multiple-choice questions. Each question contained one of the major concepts covered in the subsequent synthesis problem. Results from a small-scale interview study and two large-scale written tests showed that the scaffolding encouraged students to search for and apply appropriate fundamental principles in solving synthesis problems, and that repeated training using scaffolded synthesis problems also helped students to make cross-topic transfers.

Chaotic quantum systems

International Nuclear Information System (INIS)

Chirikov, B.V.

1991-01-01

The overview of recent developments in the theory of quantum chaos is presented with the special emphasis on a number of unsolved problems and current apparent contradictions. The relation between dynamical quantum chaos and statistical random matrix theory is discussed. 97 refs

Model-Based Illumination Correction for Face Images in Uncontrolled Scenarios

NARCIS (Netherlands)

Boom, B.J.; Spreeuwers, Lieuwe Jan; Veldhuis, Raymond N.J.

2009-01-01

Face Recognition under uncontrolled illumination conditions is partly an unsolved problem. Several illumination correction methods have been proposed, but these are usually tested on illumination conditions created in a laboratory. Our focus is more on uncontrolled conditions. We use the Phong model

Combining Illumination Normalization Methods for Better Face Recognition

NARCIS (Netherlands)

Boom, B.J.; Tao, Q.; Spreeuwers, Lieuwe Jan; Veldhuis, Raymond N.J.

2009-01-01

Face Recognition under uncontrolled illumination conditions is partly an unsolved problem. There are two categories of illumination normalization methods. The first category performs a local preprocessing, where they correct a pixel value based on a local neighborhood in the images. The second

A new characterization of L2(p) by NSE

Indian Academy of Sciences (India)

In this paper we give a new characterization of simple group L2(p) with ... Introduction. Throughout this paper, all groups are finite and G denotes a group. .... [5] Mazurov V D and Khukhro E I, Unsolved Problems in Group Theory, the Kourovka.

Music Information Retrieval Using Biologically Inspired Techniques

NARCIS (Netherlands)

Bountouridis, D.

2018-01-01

The computational modeling of our perception of music similarity is an intricate, unsolved problem with various practical applications. Many of the current approaches aim at solving it by employing heuristics, such as expert intuition or music theory, which limit their application to narrow

Problem-based learning

NARCIS (Netherlands)

Loyens, Sofie; Kirschner, Paul A.; Paas, Fred

2010-01-01

Loyens, S. M. M., Kirschner, P. A., & Paas, F. (2011). Problem-based learning. In S. Graham (Editor-in-Chief), A. Bus, S. Major, & L. Swanson (Associate Editors), APA educational psychology handbook: Vol. 3. Application to learning and teaching (pp. 403-425). Washington, DC: American Psychological

Ethnic differences in problem perception and perceived need as determinants of referral in young children with problem behaviour.

Science.gov (United States)

Bevaart, Floor; Mieloo, Cathelijne L; Donker, Marianne C H; Jansen, Wilma; Raat, Hein; Verhulst, Frank C; van Oort, Floor V A

2014-05-01

An underrepresentation of ethnic minority children in mental health care settings is consistently reported. Parents of ethnic minority children are, however, less likely to perceive problem behaviour in their children. Our hypothesis was that, as a result of ethnic differences in problem perception, referral to care by a child health professional (CHP) would be lower for 5- to 6-year-old (high-risk) children from ethnic minority backgrounds than for their peers from the ethnic majority (Dutch origin). For 10,951 children in grade two of elementary school, parents and/or teachers completed the Strengths and Difficulties Questionnaire (SDQ) as well as questions on problem perception (PP) and perceived need for professional care (PN). Referral information was obtained from the Electronic Child Records (ECR) for 1,034 of these children. These children had a high (>90th percentile) SDQ score, and were not receiving mental health care. CHP's referred 144 children (14 %) during the routine health assessments. A lower problem perception was reported by parents of ethnic minority children (40-72 %) than by parents of the ethnic majority group (80 %; p ethnic differences in referral (OR range 0.9-1.9-p > 0.05). No ethnic differences were found for parental PN, nor for teacher's PP or PN. Despite a lower problem perception in ethnic minority parents when compared to ethnic majority parents, no ethnic differences were found in referral of children with problem behaviour in a preventive health care setting.

When dogs look back: inhibition of independent problem-solving behaviour in domestic dogs (Canis lupus familiaris) compared with wolves (Canis lupus).

Science.gov (United States)

Udell, Monique A R

2015-09-01

Domestic dogs have been recognized for their social sensitivity and aptitude in human-guided tasks. For example, prior studies have demonstrated that dogs look to humans when confronted with an unsolvable task; an action often interpreted as soliciting necessary help. Conversely, wolves persist on such tasks. While dogs' 'looking back' behaviour has been used as an example of socio-cognitive advancement, an alternative explanation is that pet dogs show less persistence on independent tasks more generally. In this study, pet dogs, shelter dogs and wolves were given up to three opportunities to open a solvable puzzle box: when subjects were with a neutral human caretaker, alone and when encouraged by the human. Wolves were more persistent and more successful on this task than dogs, with 80% average success rate for wolves versus a 5% average success rate for dogs in both the human-in and alone conditions. Dogs showed increased contact with the puzzle box during the encouragement condition, but only a moderate increase in problem-solving success. Social sensitivity appears to play an important role in pet and shelter dogs' willingness to engage in problem-solving behaviour, which could suggest generalized dependence on, or deference to, human action. © 2015 The Author(s).

Solving Multiple Timetabling Problems at Danish High Schools

DEFF Research Database (Denmark)

Kristiansen, Simon

name; Elective Course Student Sectioning. The problem is solved using ALNS and solutions are proven to be close to optimum. The algorithm has been implemented and made available for the majority of the high schools in Denmark. The second Student Sectioning problem presented is the sectioning of each...... high schools. Two types of consultations are presented; the Parental Consultation Timetabling Problem (PCTP) and the Supervisor Consultation Timetabling Problem (SCTP). One mathematical model containing both consultation types has been created and solved using an ALNS approach. The received solutions...... problems as mathematical models and solve them using operational research techniques. Two of the models and the suggested solution methods have resulted in implementations in an actual decision support software, and are hence available for the majority of the high schools in Denmark. These implementations...

Some problems of recent 'All Japan' strategy for nuclear power exports. Identification of its problems and a proposal for improvement based on international development strategies of the major three categories of businesses constituting nuclear power industry

International Nuclear Information System (INIS)

Tanabe, Tomoyuki

2011-01-01

In Japan, 'All Japan' strategy for nuclear power exports, which arranges engineering companies and electric utilities to sell nuclear power plants providing engineering, procurement, construction and operation abroad, with governmental support of expanded trade insurance, is strongly promoted today as a part of Japan's national growth strategy. However, 'All Japan' strategy generates some problems because the strategy does not consider difference of business strategies concerning international development of each enterprise. This report identifies problems of 'All Japan' strategy based on environmental scanning of major three categories of businesses, which are big nuclear technology companies, vendors and electric utilities constituting nuclear power industry. And this report proposes the way to improve the strategy as follows to resolve those problems. 1) It is necessary to assess the risk of the project that is to be undertaken by 'All Japan' approach carefully. 2) Governmental support for vendors is also needed because the vendors are source of strength of international development of the nuclear industry in Japan. 3) Where the cooperation among the electric utilities is necessary, imposing the risk burden on the utilities should be avoided. 4) It is necessary for government to take measures about 'Weakness' and 'Threat' that each category of business commonly faces. (author)

Density of states of colloidal glasses and supercooled liquids

NARCIS (Netherlands)

Ghosh, A.; Mari, R.; Chikkadi, V.; Schall, P.; Kurchan, J.; Bonn, D.

2010-01-01

The glass transition is perhaps the greatest unsolved problem in condensed matter physics: the main question is how to reconcile the liquid-like structure with solid-like mechanical properties. In solids, structure and mechanics are related directly through the vibrational density of states of the

Smart logistics: an enterprise architecture perspective

NARCIS (Netherlands)

van Sinderen, Marten J.; Singh, Prince Mayurank; Wieringa, Roel J.

Logistic enterprises are increasingly becoming smarter and more ecient by using real-time contextual data. A currently unsolved problem for small to medium sized logistic service providers (SMLSPs) is, how to use real time data in existing business processes & IT systems. Enterprise architecture can

Road design, human behaviour, and road accidents : towards a `learning design community'. Paper presented at the international conference `Road safety in Europe', Birmingham, England, September 9-11, 1996.

NARCIS (Netherlands)

Wegman, F.C.M.

1996-01-01

This paper discusses a number of unsolved problems in the field of road design (i.e. geometric design), human behaviour and road safety, particularly concerning the operationalisation of the existing design principles for a safe road network in terms of concrete road design in existing

Mental causation and Searle's impossible conception of unconscious intentionality

NARCIS (Netherlands)

Meijers, A.W.M.

2000-01-01

In my article I evaluate Searle's account of mental causation, in particular his account of the causal efficacy of unconscious intentional states. I argue that top-down causation and overdetermination are unsolved problems in Searle's philosophy of mind, despite his assurances to the contrary. I

2. Home 3. Journals 4. Resonance–Journal of Science Education 5 ...

Indian Academy of Sciences (India)

n Some Unsolved Problems in Number Theory. Progress Made in Recent Times. K Ramachandra. 81 BOOK REVIEWS. • Deterministic Chaos - Complex Chance Out of. Simple Necessity. A lively Introduction to Chaos. Ravindra E Amritkar. • Chemistry Today and Tomorrow - The Central,. Useful and Creative Science.

Vibration and stability behaviour of pipes conveying fluid

International Nuclear Information System (INIS)

Becker, O.

1980-01-01

Modelling, solution methods, and results related to the hydroelastic system 'pipe conveying fluid' are discussed. In particular, the vibration and stability conditions for a straightline and a curved pipe are reviewed considering constant and pulsating flow characteristics. Problems still unsolved are pointed out. (author)

Biggest bets in the universe unveiled

CERN Multimedia

Jamieson, Valerie

2004-01-01

Betting on the greatest unsolved problems in the universe is no longer the preserve of academic superstars such as Stephen Hawking. From Thursday, anyone will be able to place bets on whether the biggest physics experiments in the world will come good before 2010

Time to address the problems at the neural interface

Science.gov (United States)

Durand, Dominique M.; Ghovanloo, Maysam; Krames, Elliot

2014-04-01

Neural engineers have made significant, if not remarkable, progress in interfacing with the nervous system in the last ten years. In particular, neuromodulation of the brain has generated significant therapeutic benefits [1-5]. EEG electrodes can be used to communicate with patients with locked-in syndrome [6]. In the central nervous system (CNS), electrode arrays placed directly over or within the cortex can record neural signals related to the intent of the subject or patient [7, 8]. A similar technology has allowed paralyzed patients to control an otherwise normal skeletal system with brain signals [9, 10]. This technology has significant potential to restore function in these and other patients with neural disorders such as stroke [11]. Although there are several multichannel arrays described in the literature, the workhorse for these cortical interfaces has been the Utah array [12]. This 100-channel electrode array has been used in most studies on animals and humans since the 1990s and is commercially available. This array and other similar microelectrode arrays can record neural signals with high quality (high signal-to-noise ratio), but these signals fade and disappear after a few months and therefore the current technology is not reliable for extended periods of time. Therefore, despite these major advances in communicating with the brain, clinical translation cannot be implemented. The reasons for this failure are not known but clearly involve the interface between the electrode and the neural tissue. The Defense Advanced Research Project Agency (DARPA) as well as other federal funding agencies such as the National Science Foundation (NSF) and the National Institutes of Health have provided significant financial support to investigate this problem without much success. A recent funding program from DARPA was designed to establish the failure modes in order to generate a reliable neural interface technology and again was unsuccessful at producing a robust

Understanding emotional problems: the REBT perspective

OpenAIRE

Dryden, Windy

2008-01-01

Rational emotive behaviour therapy (REBT) is an approach to counselling and psychotherapy rooted in the CBT tradition and one that has a distinctive perspective on emotional problems.\\ud \\ud Understanding Emotional Problems provides an accurate understanding of the REBT perspective on eight major emotional problems for which help is sought: anxiety, depression, shame, guilt, unhealthy anger, hurt, unhealthy jealousy and unhealthy envy.\\ud \\ud Rather than discussing treatment methods, Windy Dr...

Rank reduction of correlation matrices by majorization

NARCIS (Netherlands)

R. Pietersz (Raoul); P.J.F. Groenen (Patrick)

2004-01-01

textabstractIn this paper a novel method is developed for the problem of finding a low-rank correlation matrix nearest to a given correlation matrix. The method is based on majorization and therefore it is globally convergent. The method is computationally efficient, is straightforward to implement,

Problem solving stages in the five square problem.

Science.gov (United States)

Fedor, Anna; Szathmáry, Eörs; Öllinger, Michael

2015-01-01

According to the restructuring hypothesis, insight problem solving typically progresses through consecutive stages of search, impasse, insight, and search again for someone, who solves the task. The order of these stages was determined through self-reports of problem solvers and has never been verified behaviorally. We asked whether individual analysis of problem solving attempts of participants revealed the same order of problem solving stages as defined by the theory and whether their subjective feelings corresponded to the problem solving stages they were in. Our participants tried to solve the Five-Square problem in an online task, while we recorded the time and trajectory of their stick movements. After the task they were asked about their feelings related to insight and some of them also had the possibility of reporting impasse while working on the task. We found that the majority of participants did not follow the classic four-stage model of insight, but had more complex sequences of problem solving stages, with search and impasse recurring several times. This means that the classic four-stage model is not sufficient to describe variability on the individual level. We revised the classic model and we provide a new model that can generate all sequences found. Solvers reported insight more often than non-solvers and non-solvers reported impasse more often than solvers, as expected; but participants did not report impasse more often during behaviorally defined impasse stages than during other stages. This shows that impasse reports might be unreliable indicators of impasse. Our study highlights the importance of individual analysis of problem solving behavior to verify insight theory.

Waring's Problem and the Circle Method

Indian Academy of Sciences (India)

other interests include classical music and mountaineering. the problems they worked on. Their proof of a slightly. Keywords weaker form of Ramanujan's original formula was pub-. Waring's problem, circle method, ... arc is fairly simple while it is the minor arc estimation that accounts for the 'major' amount of work involved!

Some remarks on applied radiation chemistry

International Nuclear Information System (INIS)

Sakurada, I.

1979-01-01

Radiation induced polymerization and grafting are two important reactions in the processing. Numerous reports concerning these subjects have appeared in the literature. There are, however, still many problems which have been left unsolved or neglected. Several problems will be taken up in this paper and discussed on experiments carried out in Osaka Laboratory for Radiation Chemistry and Department of Polymer Chemistry of Kyoto University. (author)

The mystery of knots

CERN Document Server

Aneziris, Charilaos N

1999-01-01

One of the most significant unsolved problems in mathematics is the complete classification of knots. The main purpose of this book is to introduce the reader to the use of computer programming to obtain the table of knots. The author presents this problem as clearly and methodically as possible, starting from the very basics. Mathematical ideas and concepts are extensively discussed, and no advanced background is required.

Exercise for patients with major depression

DEFF Research Database (Denmark)

Krogh, Jesper; Speyer, Helene; Gluud, Christian

2015-01-01

is to investigate the beneficial and harmful effects of exercise, in terms of severity of depression, lack of remission, suicide, and so on, compared with treatment as usual with or without co-interventions in randomized clinical trials involving adults with a clinical diagnosis of major depression. A meta......BACKGROUND: The lifetime prevalence of major depression is estimated to affect 17% of the population and is considered the second largest health-care problem globally in terms of the number of years lived with disability. The effects of most antidepressant treatments are poor; therefore, exercise...... has been assessed in a number of randomized clinical trials. A number of reviews have previously analyzed these trials; however, none of these reviews have addresses the effect of exercise for adults diagnosed with major depression. METHODS/DESIGN: The objective of this systematic review...

Crowd Sourcing for Challenging Technical Problems and Business Model

Science.gov (United States)

Davis, Jeffrey R.; Richard, Elizabeth

2011-01-01

Crowd sourcing may be defined as the act of outsourcing tasks that are traditionally performed by an employee or contractor to an undefined, generally large group of people or community (a crowd) in the form of an open call. The open call may be issued by an organization wishing to find a solution to a particular problem or complete a task, or by an open innovation service provider on behalf of that organization. In 2008, the Space Life Sciences Directorate (SLSD), with the support of Wyle Integrated Science and Engineering, established and implemented pilot projects in open innovation (crowd sourcing) to determine if these new internet-based platforms could indeed find solutions to difficult technical challenges. These unsolved technical problems were converted to problem statements, also called "Challenges" or "Technical Needs" by the various open innovation service providers, and were then posted externally to seek solutions. In addition, an open call was issued internally to NASA employees Agency wide (10 Field Centers and NASA HQ) using an open innovation service provider crowd sourcing platform to post NASA challenges from each Center for the others to propose solutions). From 2008 to 2010, the SLSD issued 34 challenges, 14 externally and 20 internally. The 14 external problems or challenges were posted through three different vendors: InnoCentive, Yet2.com and TopCoder. The 20 internal challenges were conducted using the InnoCentive crowd sourcing platform designed for internal use by an organization. This platform was customized for NASA use and promoted as NASA@Work. The results were significant. Of the seven InnoCentive external challenges, two full and five partial awards were made in complex technical areas such as predicting solar flares and long-duration food packaging. Similarly, the TopCoder challenge yielded an optimization algorithm for designing a lunar medical kit. The Yet2.com challenges yielded many new industry and academic contacts in bone

Major issues associated with nuclear power generation cost and their evaluation

International Nuclear Information System (INIS)

Matsuo, Yuji; Shimogori, Kei; Suzuki, Atsuhiko

2015-01-01

This paper discusses the evaluation of power generation cost that is an important item for energy policy planning. Especially with a focus on nuclear power generation cost, it reviews what will become a focal point on evaluating power generation cost at the present point after the estimates of the 'Investigation Committee on Costs' that was organized by the government have been issued, and what will be a major factor affecting future changes in costs. This paper firstly compared several estimation results on nuclear power generation cost, and extracted/arranged controversial points and unsolved points for discussing nuclear power generation cost. In evaluating nuclear power generation cost, the comparison of capital cost and other costs can give the understanding of what can be important issues. Then, as the main issues, this paper evaluated/discussed the construction cost, operation/maintenance cost, external cost, issue of discount rate, as well as power generation costs in foreign countries and the impact of fossil fuel prices. As other issues related to power generation cost evaluation, it took up expenses for decommissioning, disposal of high-level radioactive waste, and re-processing, outlined the evaluation results by the 'Investigation Committee on Costs,' and compared them with the evaluation examples in foreign countries. These costs do not account for a large share of the entire nuclear power generation costs. The most important point for considering future energy policy is the issue of discount rate, that is, the issue of fund-raising environment for entrepreneurs. This is the factor to greatly affect the economy of future nuclear power generation. (A.O.)

The use of silicone occlusive sheeting (Sil-K) and silicone occlusive gel (epiderm) in the prevention of hypertrophic scar formation

NARCIS (Netherlands)

Niessen, FB; Spauwen, PHM; Robinson, PH; Fidler, [No Value; Kon, M

The development of hypertrophic scars and keloids is an unsolved problem in the process of found healing. For this reason, a successful treatment to prevent excessive scar formation still has not been found. Over the last decade, however, a promising new treatment has been introduced. Silicone

Reading from the Black Box : What Sensors Tell Us about Resting and Recovery after Real-World Falls

NARCIS (Netherlands)

Schwickert, Lars; Klenk, Jochen; Zijlstra, Wiebren; Forst-Gill, Maxim; Sczuka, Kim; Helbostad, Jorunn L.; Chiari, Lorenzo; Aminian, Kamiar; Todd, Chris; Becker, Clemens

2018-01-01

Background: Lying on the floor for a long time after falls, regardless of whether an injury results, remains an unsolved health care problem. In order to develop efficient and acceptable fall detection and reaction approaches, it is relevant to improve the understanding of the circumstances and the

Benefits of the use of natural user interfaces in water simulations

NARCIS (Netherlands)

Donchyts, G.; Baart, F.; Van Dam, A.; Jagers, B.

2014-01-01

The use of natural user interfaces instead of conventional ones has become a reality with the emergence of 3D motion sensing technologies. However, some problems are still unsolved (for example, no haptic or tactile feedback); so this technology requires careful evaluation before the users can

Lignin Sulfonation - A different Approach

DEFF Research Database (Denmark)

Bjørkmann, Anders

2001-01-01

The research on sulfite pulping has been characterized by the attempts to explain its chemistry. The. different approach presented is incited by perceptions about the (still) unsolved problem of the ultrastructural features of lignin in wood. A simple kinetic model has been chosen to describe the...

Ramsey theory on the integers

CERN Document Server

Landman, Bruce M

2003-01-01

Ramsey theory is the study of the structure of mathematical objects that is preserved under partitions. In its full generality, Ramsey theory is quite powerful, but can quickly become complicated. By limiting the focus of this book to Ramsey theory applied to the set of integers, the authors have produced a gentle, but meaningful, introduction to an important and enticing branch of modern mathematics. Ramsey Theory on the Integers offers students something quite rare for a book at this level: a glimpse into the world of mathematical research and the opportunity to begin pondering unsolved problems themselves. In addition to being the first truly accessible book on Ramsey theory, this innovative book also provides the first cohesive study of Ramsey theory on the integers. It contains perhaps the most substantial account of solved and unsolved problems in this blossoming subarea of Ramsey theory. The result is a breakthrough book that will engage students, teachers, and researchers alike.

On Stackelberg and Inverse Stackelberg Games and Their Applications in the Optimal Toll Design Problem, the Energy Markets Liberalization Problem, and in the Theory of Incentives

Energy Technology Data Exchange (ETDEWEB)

Stankova, K.

2009-02-02

Inverse (or reverse) Stackelberg games have become the subject of recent game theory research, as a special type or as an extension of Stackelberg games. So far, only very little theory about inverse Stackelberg games is available and the available theory is still in its infancy. In this thesis we focus on theoretically solving such problems and we propose to treat several challenging problems in various fields inside this framework. In Stackelberg games a so-called leader determines actions for one or more so-called followers. The problem of finding an optimal strategy for the leader in these games is in general extremely hard to solve, and often even completely unsolvable. Starting from simple static problems and proceeding to more difficult dynamic ones, we show how to find the optimal strategy for the leader in a heuristic manner. In this thesis, the application of game theory is proposed in the following domains: The optimal toll design problem, the electricity markets liberalization problem, and the theory of incentives. The optimal toll design problem is a game of the Stackelberg type in which a road authority acts as the leader and drivers in the road network act as the followers. The road authority sets tolls on some of the links in the network in order to maximize its objective function, while the drivers make their travel decisions in order to minimize their perceived travel costs. If the toll that the road authority sets is traffic-flow invariant, the problem is the 'classical' Stackelberg game; if the toll is traffic-flow dependent, the problem is of the inverse Stackelberg type. We determine the optimal traffic-flow dependent toll for the road authority for both static and dynamic variants of the problem. If the solution concept for the drivers' behavior is the deterministic user equilibrium, the problem can be dealt with analytically. If the stochastic user equilibrium applies, numerical methods have to be applied to find a solution

On Stackelberg and Inverse Stackelberg Games and Their Applications in the Optimal Toll Design Problem, the Energy Markets Liberalization Problem, and in the Theory of Incentives

International Nuclear Information System (INIS)

Stankova, K.

2009-01-01

Inverse (or reverse) Stackelberg games have become the subject of recent game theory research, as a special type or as an extension of Stackelberg games. So far, only very little theory about inverse Stackelberg games is available and the available theory is still in its infancy. In this thesis we focus on theoretically solving such problems and we propose to treat several challenging problems in various fields inside this framework. In Stackelberg games a so-called leader determines actions for one or more so-called followers. The problem of finding an optimal strategy for the leader in these games is in general extremely hard to solve, and often even completely unsolvable. Starting from simple static problems and proceeding to more difficult dynamic ones, we show how to find the optimal strategy for the leader in a heuristic manner. In this thesis, the application of game theory is proposed in the following domains: The optimal toll design problem, the electricity markets liberalization problem, and the theory of incentives. The optimal toll design problem is a game of the Stackelberg type in which a road authority acts as the leader and drivers in the road network act as the followers. The road authority sets tolls on some of the links in the network in order to maximize its objective function, while the drivers make their travel decisions in order to minimize their perceived travel costs. If the toll that the road authority sets is traffic-flow invariant, the problem is the 'classical' Stackelberg game; if the toll is traffic-flow dependent, the problem is of the inverse Stackelberg type. We determine the optimal traffic-flow dependent toll for the road authority for both static and dynamic variants of the problem. If the solution concept for the drivers' behavior is the deterministic user equilibrium, the problem can be dealt with analytically. If the stochastic user equilibrium applies, numerical methods have to be applied to find a solution. As the problem

Problems of Uranium Monocarbide and Mononitride Technology; Problemes de la technologie des monocarbures et mononitrures d'uranium; Problemy tekhnologii monokarbida i mononitrida urana; Problemas de la tecnologia del monocarburo y del mononitruro de uranio

Energy Technology Data Exchange (ETDEWEB)

Yakeshova, L. [Institut Yadernykh Issledovanij Chekhoslovatskoj, Czechoslovak Socialist Republic (Czech Republic)

1963-11-15

A critical account of published data is given, and the over-all demands made on ceramic nuclear fuel of the uranium monocarbide and mononitride type are examined. The paper also refers to a number of still unsolved problems, either at the research level or at that of practical application. A short account is given of methods of obtaining monocarbide and preparing compacted products. (author) [French] Le memoire donne un apercu critique de la documentation publiee. Il examine les criteres generaux auxquels doit repondre le combustible nucleaire ceramique du type monocarbure et mononitrure d'uranium. Il indique les problemes qui se posent encore en ce qui concerne les travaux de recherche ou l'utilisation pratique des matieres. Les methodes de preparation des monocarbures et les questions relatives a la fabrication de produits compacts font l'objet d'un bref examen. (author) [Spanish] La memoria examina criticamente los datos publicados. Se exponen los requisitos generales de los combustibles nucleares ceramicos del tipo monocarburo y mononitruio de uranio. Se senalan los problemas aun no resueltos en lo relativo a los trabajos de investigacion o a las aplicaciones practicas de esos materiales. Se describen brevemente los metodos de preparacion de los monocarburos y los problemas que plantean la elaboracion de productos compactos. (author) [Russian] Daetsya kriticheskoe obsuzhdenie literaturnykh dannykh. Razbirayutsya obshchie trebovaniya k keramicheskomu yadernomu toplivu tipa monokarbida i mononitrida urana. Otmechayutsya problemy, kotorye s tochki zreniya issledovatel'skikh rabot ili prakticheskogo primeneniya materialov, ostayutsya eshche ne reshennymi. Kratko obsuzhdayutsya metoda polucheniya monokargida i voprosy prigotovleniya kompaktnykh izdelij. (author)

The Emerging Physics of Consciousness

CERN Document Server

Tuszynski, Jack A

2006-01-01

Consciousness remains one of the major unsolved problems in science. How do the feelings and sensations making up conscious experience arise from the concerted actions of nerve cells and their associated synaptic and molecular processes? Can such feelings be explained by modern science, or is there an entirely different kind of explanation needed? And how can this seemingly intractable problem be approached experimentally? How do the operations of the conscious mind emerge out of the specific interactions involving billions of neurons? This book seeks answers to these questions on the underlying assumption that consciousness can be understood using the intellectual potential of modern physics and other sciences. There are a number of theories of consciousness, some based on classical physics while others require the use of quantum concepts. The latter ones have drawn criticism from the parts of the scientific establishment while simultaneously claiming that classical approaches are doomed to failure. The cont...

Enhancing in situ hydrogen peroxide generation of greige cotton nonwoven wound dressings via ascorbate stabilized copper micro- and nano-particles

Science.gov (United States)

Understanding how wound dressings may be designed to address critical unsolved issues in wound repair and treatment influences the development of dressings and new concepts of promoting healing. The vast majority of commercial dressing materials focus on the physical aspects of wounds, e.g., acting ...

Perturbation analysis of linear control problems

International Nuclear Information System (INIS)

Petkov, Petko; Konstantinov, Mihail

2017-01-01

The paper presents a brief overview of the technique of splitting operators, proposed by the authors and intended for perturbation analysis of control problems involving unitary and orthogonal matrices. Combined with the technique of Lyapunov majorants and the implementation of the Banach and Schauder fixed point principles, it allows to obtain rigorous non-local perturbation bounds for a set of sensitivity analysis problems. Among them are the reduction of linear systems into orthogonal canonical forms, the feedback synthesis problem and pole assignment problem in particular, as well as other important problems in control theory and linear algebra. Key words: perturbation analysis, canonical forms, feedback synthesis

World-wide environmental problems

International Nuclear Information System (INIS)

Wohlers, H.C.

1975-01-01

Man and the physical and natural resources necessary to support him in a civilized society are on a collision course. It is simple to say that man cannot continue to grow in number at an ever-increasing rate without a destructive effect upon the environment. Positive scientific proof for this impending calamity is not now available, yet many indications--sometimes physical and sometimes natural--point toward major world-wide environmental troubles in the near future. A number of environmental problems are described, particularly as they relate to the total world system. A computer model simulating future world-wide environmental trends from 1900 to 2100 A.D. is evaluated and suggested as a major tool for data-gathering purposes to determine the extent of world-wide environmental problems. It is suggested that scientists take an active role in the study of the environment, particularly in relation to man's future on earth

Radiation streaming: the continuing problem of shield design

International Nuclear Information System (INIS)

Avery, A.F.

1977-01-01

The practical problems of shield design are reviewed and the major difficulties are shown to be those associated with streaming problems. The situations in which streaming occurs in various types of reactor are described including LMFBR's and fusion devices, and examples are given of ways in which the problems have been solved

A prospective, randomised, controlled, double-blind phase I-II clinical trial on the safety of A-Part® Gel as adhesion prophylaxis after major abdominal surgery versus non-treated group

Directory of Open Access Journals (Sweden)

Weis Christine

2010-07-01

Full Text Available Abstract Background Postoperative adhesions occur when fibrous strands of internal scar tissue bind anatomical structures to one another. The most common cause of intra-abdominal adhesions is previous intra-abdominal surgical intervention. Up to 74% of intestinal obstructions are caused by post surgical adhesions. Although a variety of methods and agents have been investigated to prevent post surgical adhesions, the problem of peritoneal adhesions remains largely unsolved. Materials serving as an adhesion barrier are much needed. Methods/Design This is a prospective, randomised, controlled, patient blinded and observer blinded, single centre phase I-II trial, which evaluates the safety of A-Part® Gel as an adhesion prophylaxis after major abdominal wall surgery, in comparison to an untreated control group. 60 patients undergoing an elective median laparotomy without prior abdominal surgery are randomly allocated into two groups of a 1:1- ratio. Safety parameter and primary endpoint of the study is the occurrence of wound healing impairment or peritonitis within 28 (+10 days after surgery. The frequency of anastomotic leakage within 28 days after operation, occurrence of adverse and serious adverse events during hospital stay up to 3 months and the rate of adhesions along the scar within 3 months are defined as secondary endpoints. After hospital discharge the investigator will examine the enrolled patients at 28 (+10 days and 3 months (±14 days after surgery. Discussion This trial aims to assess, whether the intra-peritoneal application of A-Part® Gel is safe and efficacious in the prevention of post-surgical adhesions after median laparotomy, in comparison to untreated controls. Trial registration NCT00646412

A Multivariate Model of Physics Problem Solving

Science.gov (United States)

Taasoobshirazi, Gita; Farley, John

2013-01-01

A model of expertise in physics problem solving was tested on undergraduate science, physics, and engineering majors enrolled in an introductory-level physics course. Structural equation modeling was used to test hypothesized relationships among variables linked to expertise in physics problem solving including motivation, metacognitive planning,…

Potentials of mean force for protein structure prediction vindicated, formalized and generalized

DEFF Research Database (Denmark)

Hamelryck, Thomas; Borg, Mikael; Paluszewski, Martin

2010-01-01

and the simulation of protein folding. However, the validity, scope and limitations of these potentials are still vigorously debated and disputed, and the optimal choice of the reference state--a necessary component of these potentials--is an unsolved problem. PMFs are loosely justified by analogy to the reversible...

Bacteria associated with the coral Echinopora lamellosa (Esper ...

African Journals Online (AJOL)

USER

2007-12-10

Dec 10, 2007 ... with diseased corals in the Indian Ocean. However ... Indian Ocean, mucus samples were collected from healthy and apparently diseased Echinopora ..... The rising tide of ocean diseases: unsolved problems and research priorities. Front. Ecol. Environ. 2: 375-382. Harvell D, Jordan-Dahlgren E, Merkel S, ...

Wave-to-wire Modelling of Wave Energy Converters

DEFF Research Database (Denmark)

Ferri, Francesco

The wild development of the world from the 1769, years in which James Watt patented his steam engine, brought utterly to the actual, real or assumed, economical, political, environmental and energetic crisis. The answer to the question “how to solve these problems?" is a tangled unsolved discussi...

Wylfa nuclear boiler repair. How a major problem was solved

International Nuclear Information System (INIS)

1977-09-01

The CEGB has published a booklet, with coloured illustrations, that describes in detail the story of an unusually difficult boiler repair on a Magnox reactor at Wylfa nuclear power station. Boiler leaks affected the operation of No. 2 reactor in 1972, and persisted during 1973. A special procedure was developed for plugging the leaks using a remote welding machine but with the incidence of leaks continuing attempts were made to obtain a specimen of leaking tube by cutting through the boiler support tank to gain access. Eventually the fault was then traced to excessive relative motion between the tubes and support clips. Remedial work took seven months and was completed in December 1975. The start of the problem and the method of plugging the leaks is described. Details are given of the investigation leading to the obtaining and examination of a sample of leaking tube and the determination of the fault. Establishment of the cause as an unusual form of resonant vibration causing wear and fretting in clip-to-tube positions in the economiser region of the boiler is described in detail. The difficulties and accomplishments of the repair work are detailed. Finally the operation is looked at in retrospect and the experiences gained are summarised. (UK)

Elementary School Teacher Candidates' Perceptions of Good Problems

Science.gov (United States)

Lee, Ji-Eun; Kim, Kyoung-Tae

2005-01-01

This study describes a classroom action research activity regarding a group of elementary school teacher candidates' perceptions of good mathematics problems. A questionnaire containing 20 problems was given, and the candidates were asked to rate the quality of each problem on a 5-point scale. The results revealed that the majority of the teacher…

Deregulation of the electric power industry in Europe and in the USA: a decomposition-recombining process

International Nuclear Information System (INIS)

Percebois, J.

1997-07-01

The deregulation of electric industry in Europe and in the U.S.A. assumes various aspects according to each country. Several institutional, economic and political reasons explain this evolution. Electric firms take this opportunity to merge and to implement offensive strategies on global markets. A lot of questions remains unsolved, in particular the problem of TPA pricing and the problem of planning of network infrastructures over the long run. (authors)

Deregulation of the electric power industry in Europe and in the USA: a decomposition-recombining process; La deregulation de l'industrie electrique en Europe et aux Etats-Unis: un processus de decomposition-recomposition

Energy Technology Data Exchange (ETDEWEB)

Percebois, J

1997-07-01

The deregulation of electric industry in Europe and in the U.S.A. assumes various aspects according to each country. Several institutional, economic and political reasons explain this evolution. Electric firms take this opportunity to merge and to implement offensive strategies on global markets. A lot of questions remains unsolved, in particular the problem of TPA pricing and the problem of planning of network infrastructures over the long run. (authors)

Deregulation of the electric power industry in Europe and in the USA: a decomposition-recombining process; La deregulation de l'industrie electrique en Europe et aux Etats-Unis: un processus de decomposition-recomposition

Energy Technology Data Exchange (ETDEWEB)

Percebois, J

1997-07-01

The deregulation of electric industry in Europe and in the U.S.A. assumes various aspects according to each country. Several institutional, economic and political reasons explain this evolution. Electric firms take this opportunity to merge and to implement offensive strategies on global markets. A lot of questions remains unsolved, in particular the problem of TPA pricing and the problem of planning of network infrastructures over the long run. (authors)

Social work role in developing and managing employee assistance programs in health care settings.

Science.gov (United States)

Foster, Z; Hirsch, S; Zaske, K

1991-01-01

The hospital setting presents special needs for an Employee Assistance Program and special complications for sponsorship, development, and maintenance. What has been learned, how certain problems can be solved or avoided, how responsibility and accountability can be negotiated are presented by a team that has successfully established such a program at a large metropolitan medical center. In addition to successes, some unsolved problems are identified for further study.

Abstract Cauchy problems three approaches

CERN Document Server

Melnikova, Irina V

2001-01-01

Although the theory of well-posed Cauchy problems is reasonably understood, ill-posed problems-involved in a numerous mathematical models in physics, engineering, and finance- can be approached in a variety of ways. Historically, there have been three major strategies for dealing with such problems: semigroup, abstract distribution, and regularization methods. Semigroup and distribution methods restore well-posedness, in a modern weak sense. Regularization methods provide approximate solutions to ill-posed problems. Although these approaches were extensively developed over the last decades by many researchers, nowhere could one find a comprehensive treatment of all three approaches.Abstract Cauchy Problems: Three Approaches provides an innovative, self-contained account of these methods and, furthermore, demonstrates and studies some of the profound connections between them. The authors discuss the application of different methods not only to the Cauchy problem that is not well-posed in the classical sense, b...

Sales plan generation problem on TV broadcasting

OpenAIRE

Özlem Cosgun; İlkay Gultas

2016-01-01

Major advertisers and/or advertisement agencies purchase hundreds of slots during a given broadcast period. Deterministic optimization approaches have been well developed for the problem of meeting client requests. The challenging task for the academic research currently is to address optimization problem under uncertainty. This paper is concerned with the sales plan generation problem when the audience levels of advertisement slots are random variables with known probability distributions. T...

Smokeless tobacco: a major public health problem in the SEA region: a review.

Science.gov (United States)

Gupta, Prakash C; Ray, Cecily S; Sinha, Dhirendra N; Singh, Poonam K

2011-01-01

Smokeless tobacco use is on the upswing in some parts of the world, including parts of SEAR. It is therefore important to monitor this problem and understand the possible consequences on public health. Material for this review was obtained from documents and data of the World Health Organization, co-authors, colleagues, and searches on key words in PubMed and on Google. Smokeless tobacco use in SEAR, as betel quid with tobacco, declined with increased marketing of cigarettes from the early twentieth century. Smokeless tobacco use began to increase in the 1970s in South Asia, with the marketing of new products made from areca nut and tobacco and convenient packaging. As a consequence, oral precancerous conditions and cancer incidence in young adults have increased significantly. Thailand's successful policies in reducing betel quid use through school health education from the 1920s and in preventing imports of smokeless tobacco products from 1992 are worth emulating by many SEAR countries. India, the largest manufacturing country of smokeless tobacco in the Region, is considering ways to regulate its production. Best practices require the simultaneous control of smokeless and smoking forms of tobacco. Governments in SEAR would do well to adopt strong measures now to control this problem.

Application of the random phase approximation to complex problems in materials science

International Nuclear Information System (INIS)

Schimka, L.

2012-01-01

This thesis is devoted to the assessment and application of the random phase approximation (RPA) in the adiabatic-connection fluctuation-dissipation (ACFD) framework in solid state physics. The first part presents a review of density functional theory (DFT) and the ACFD theorem in the RPA. This includes an introduction to the many-body problem as well as a description of the implementation of the RPA in the Vienna Ab-initio Simulation Package (VASP). In the results part, the quality of the RPA is assessed and its performance compared to three (beyond) DFT functionals. The experimental values are corrected for the effect of phonon zero-point vibrational energies which were calculated at the DFT level from ab-initio. We find that the RPA describes all bonding situations very accurately, making it a promising candidate for more complex problems in solid state physics. In light of these findings, we investigate the carbon-water interaction in two specific cases: the adsorption of water on benzene and the adsorption of water on a graphene layer. We compare our results to a different correlated method: diffusion Monte Carlo (DMC). We find very good agreement and thus believe that our values can serve as a benchmark for the development of other DFT functionals to treat water-carbon interfaces. The highlight of this thesis is the successful application of the RPA to the long-standing and (at DFT level) unsolved CO adsorption puzzle. We show results for CO adsorption on Cu, late 4d metals and Pt. RPA is at present the only ab-initio method that describes adsorption and surface energies accurately at the same time and predicts the correct adsorption site in every single case. (author) [de

Kinetics of contrail particles formation and heterogeneous reactions on such particles

Energy Technology Data Exchange (ETDEWEB)

Kogan, M.N.; Butkovsky, A.V.; Erofeev, A.I.; Freedlender, O.G.; Makashev, N.K. [Central Aerohydrodynamic Inst., Zhukovsky (Russian Federation)

1997-12-31

The research of impact of aircraft emissions upon the atmosphere is very complex and difficult problem. More than two decades of intensive investigations of the problem of ozone decay do not permit to make definite conclusions. Many important problems still remain unsolved in the aircraft/atmosphere interaction: engine, nozzle, jet, jet/vortex system interaction, vortex breakdown, contrail formation, meso-scale and global processes, their effects on climate. The particles formation and heterogeneous reactions play an important role in some of these processes. These problems are discussed. (author) 11 refs.

Kinetics of contrail particles formation and heterogeneous reactions on such particles

Energy Technology Data Exchange (ETDEWEB)

Kogan, M N; Butkovsky, A V; Erofeev, A I; Freedlender, O G; Makashev, N K [Central Aerohydrodynamic Inst., Zhukovsky (Russian Federation)

1998-12-31

The research of impact of aircraft emissions upon the atmosphere is very complex and difficult problem. More than two decades of intensive investigations of the problem of ozone decay do not permit to make definite conclusions. Many important problems still remain unsolved in the aircraft/atmosphere interaction: engine, nozzle, jet, jet/vortex system interaction, vortex breakdown, contrail formation, meso-scale and global processes, their effects on climate. The particles formation and heterogeneous reactions play an important role in some of these processes. These problems are discussed. (author) 11 refs.

Gravitational collapse with decaying vacuum energy

Indian Academy of Sciences (India)

To explain this acceleration, it is necessary to ... One of the most important unsolved theoretical problems in classical general relativity is the cosmic ... Penrose [5] first proposed that general relativity does not admit naked singularities. ... It is now known that there are a number of solutions of Einstein's equations which admit.

Investigating School-Wide Antecedents of Good Practice Dissemination from Individual Subject Projects

Science.gov (United States)

Christophersen, Knut-Andreas; Elstad, Eyvind; Turmo, Are

2012-01-01

Good practice dissemination is an unsolved problem in education. This article describes how clear and "soft" leadership and perceptions of social and economic exchange operate in the bottom-up processes of school reforms and examines the relative impact of these factors on school-wide good practice dissemination and discusses how…

Silica Sulphuric Acid as an Efficient Catalyst for the Catalytic and ...

African Journals Online (AJOL)

NJD

presence of a catalytic amount of silica sulphuric acid under micellar media in moderate to good yields. KEYWORDS. Sodium ... Production of aromatic nitro compounds is an important industrial process and involves the unsolved problems of ... V7 and Re9) and titanium and chromium silicates.10 Some of the procedures ...

Combining Paraconsistent Logic with Argumentation

NARCIS (Netherlands)

Grooters, Diana; Prakken, Hendrik

2014-01-01

One tradition in the logical study of argumentation is to allow for arguments that combine strict and defeasible inference rules, and to derive the strict inference rules from a logic at least as strong as classical logic. An unsolved problem in this tradition is how the trivialising effect of the

Children with Autism Spectrum Disorder Have an Exceptional Explanatory Drive

Science.gov (United States)

Rutherford, M. D.; Subiaul, Francys

2016-01-01

An "explanatory drive" motivates children to explain ambiguity. Individuals with autism spectrum disorders are interested in how systems work, but it is unknown whether they have an explanatory drive. We presented children with and without autism spectrum disorder unsolvable problems in a physical and in a social context and evaluated…

Kirkham’s legacy and contemporary challenges in soil physics research

Science.gov (United States)

This paper, written by the winners of the Don and Betty Kirkham Award in Soil Physics, is dedicated to the legacy of Don Kirkham. It describes eight longstanding or emerging research areas in soil physics that contain key unsolved problems. All are field-oriented with applications to a number of imp...

Little evidence for dynamic divergences in ultraviscous molecular liquids

DEFF Research Database (Denmark)

Hecksher, Tina; Nielsen, Albena; Olsen, Niels Boye

2008-01-01

The physics of the ultraviscous liquid phase preceding glass formation continues to pose major problems that remain unsolved. It is actively debated, for instance, whether the marked increase of the relaxation time reflects an underlying phase transition to a state of infinite relaxation time....... To elucidate the empirical evidence for this intriguing scenario, some of the most accurate relaxationtime data available for any class of ultraviscous liquids-those obtained by dielectric relaxation experiments on organic liquids just above the glass transition-were compiled. Analysis of data for 42 liquids...... shows that there is no compelling evidence for the Vogel-Fulcher-Tammann (VFT) prediction that the relaxation time diverges at a finite temperature.We conclude that theories with a dynamic divergence of the VFT formlack a direct experimental basis....

On generalized operator quasi-equilibrium problems

Science.gov (United States)

Kum, Sangho; Kim, Won Kyu

2008-09-01

In this paper, we will introduce the generalized operator equilibrium problem and generalized operator quasi-equilibrium problem which generalize the operator equilibrium problem due to Kazmi and Raouf [K.R. Kazmi, A. Raouf, A class of operator equilibrium problems, J. Math. Anal. Appl. 308 (2005) 554-564] into multi-valued and quasi-equilibrium problems. Using a Fan-Browder type fixed point theorem in [S. Park, Foundations of the KKM theory via coincidences of composites of upper semicontinuous maps, J. Korean Math. Soc. 31 (1994) 493-519] and an existence theorem of equilibrium for 1-person game in [X.-P. Ding, W.K. Kim, K.-K. Tan, Equilibria of non-compact generalized games with L*-majorized preferences, J. Math. Anal. Appl. 164 (1992) 508-517] as basic tools, we prove new existence theorems on generalized operator equilibrium problem and generalized operator quasi-equilibrium problem which includes operator equilibrium problems.

The construct validity of the Major Depression Inventory

DEFF Research Database (Denmark)

Nielsen, Marie Germund; Ørnbøl, Eva; Vestergaard, Mogens

2017-01-01

Objective We aimed to assess the measurement properties of the ten-item Major Depression Inventory when used on clinical suspicion in general practice by performing a Rasch analysis. Methods General practitioners asked consecutive persons to respond to the web-based Major Depression Inventory...... on clinical suspicion of depression. We included 22 practices and 245 persons. Rasch analysis was performed using RUMM2030 software. The Rasch model fit suggests that all items contribute to a single underlying trait (defined as internal construct validity). Mokken analysis was used to test dimensionality...... for gender, age, work status and education. The Rasch and Mokken analyses revealed two dimensions, but the Major Depression Inventory showed fit to one scale if items 9 and 10 were excluded. Conclusion Our study indicated scalability problems in the current version of the Major Depression Inventory...

Traumatic Brain Injury: Caregivers’ Problems and Needs

OpenAIRE

syed tajjudin syed hassan; WF Khaw; AR Rosna; J Husna

2011-01-01

Traumatic brain injury (TBI) is an increasingly major world health problem. This short review using the most pertinent articles on TBI caregiving problems and needs highlights the pressing issues. Articles focusing on both TBI-caregivers’ problems and needs are rarely found, especially for developing countries. Most TBI-caregiving is done by family members, whose altered lives portend burden and stresses which add to the overwhelming demand of caring for the TBI-survivor. Lack of information,...

Can nuclear power be accepted today in the light of the waste management problem

International Nuclear Information System (INIS)

Schueller, W.

1978-01-01

The waste management problem occupies a central position in the public debate about nuclear power. Even many proponents of this source of power share the concern that the seemingly unsolved problems associated with the disposal of radioactive waste might lead into a technological blind alley. The nuclear fuel cycle, including plutonium reycling in light water reactors, has been practised in the Federal Republic on a technical scale for many years. The three demonstration plants used for this purpose, i.e., KWO, WAK and ALKEM, represent an aggregate capital investment of some DM 830 million and have a staff of at present approximately 900 persons. More than 24 years of experience on a technical scale is available for the Purex process used for reprocessing. The experience of German industry in reprocessing high-burnup oxide LWR fuel elements is based on the operation of two experimental facilities over a period of twelve years, almost seven years of which are for the WAK, which successfully reprocessed fuel elements with burnups as high as 39.000 MWd/t of uranium. The article specifically discusses the doubts frequently expressed about the extrapolability of operating experience accumulated in processing low-burnup fuels to fuel with high burnup, i.e., from the Karlsruhe experimental scale facility to the large scale plant of the waste management center. The objections often raised against the planned upscaling of plant throughputs when moving to industrial scale processes do not take into account that the decisive operating experience generated in the technical radiochemistry is hardly a function of material throughputs, but rather refers to the specialized techniques employed in handling radioactive and fissile materials. (orig.) [de

MicroRNA and Cancer: Tiny Molecules with Major Implications

OpenAIRE

VandenBoom II, Timothy G; Li, Yiwei; Philip, Philip A; Sarkar, Fazlul H

2008-01-01

Cancer is currently a major public health problem and, as such, emerging research is making significant progress in identifying major players in its biology. One recent topic of interest involves microRNAs (miRNAs) which are small, non-coding RNA molecules that inhibit gene expression post-transcriptionally. They accomplish this by binding to the 3? untranslated region (3?UTR) of target messengerRNA (mRNA), resulting in either their degradation or inhibition of translation, depending on the d...

Breast cancer scenario in a regional cancer centre in Eastern India over eight years--still a major public health problem.

Science.gov (United States)

Datta, Karabi; Choudhuri, Maitrayee; Guha, Subhas; Biswas, Jaydip

2012-01-01

In spite of screening and early diagnostic tests, the upward trend of breast cancer has become a matter of great concern in both developed and developing countries. The data collected by Population Based Cancer Registry in Chittaranjan National Cancer Institute, a regional cancer centre in Kolkata, from 1997 to 2004 gives an insight about the scenario of breast cancer in this part of Eastern India. The total no of female breast cancer cases were steadily increasing from 1997 to 2001 and only slightly lower from 2002 to 2004. and majority were in the 40-49 year old age group during this period. The next most commonly affected age group was 50-59 years. Regarding the distribution according to treatment, the main modality was surgery and radiotherapy followed by combined surgery, chemotherapy and radiotherapy and then combined surgery and chemotherapy. The commonest type was ductal followed by lobular cancer. In this eight year study in CNCI, status of patients on last day of the respective year was assessed. Number of patients alive was 43.5% in 1997. The percentage gradually increased up to 2000 and then gradually decreased to 47.4% in 2004. Also with every passing year, percentage mortality gradually decreased from 25.7% in 1997 to 16.8% in 2004. Better pattern of care (diagnosis and treatment) was reflected in this picture. However, lost to follow up, which also implies non compliance to treatment, increased to 30.8% in 1997 to 35.8% in 2004. Due to the small number of male breast cancers, only female cases were considered. In conclusion, breast cancer continues to be a major problem in Kolkata, India.

Greenhouse problem in the Amazon jungle clearing

International Nuclear Information System (INIS)

Reis, E.J.; Margulis, S.

1991-01-01

This paper discusses the contribution of Amazon jungle clearing to the greenhouse problem and makes an assessment of long-run prospects. The introductory sections pose the problem from both international and Brazilian perspectives. The next section describes major features of the Amazonia ecosystems and presents methods and evidence on deforestation and on its impact on carbon dioxide emissions. Based upon cross-section information for a sample of municipalities in the Brazilian Amazon, the following section estimates elasticities of deforestation in relation to major economic factors- government policies included- and uses them to make projections for the future pace of deforestation. The last section discusses policy alternatives to slow down forest conversion

LABORATORY MODELING OF TORNADOES

OpenAIRE

文字, 信貴

1982-01-01

Laboratory modelings of the tornado vortices are overviewed. Modelings of the mesocyclone as theboundary conditions in the tornado simulations are found to have significant problems especially on thesource of thunderstorm and tornado rotation. A number of the problems related to the vortex structuresuch as the wind profiles or the role of turbulence are left unsolved. However, the simulated vortices arefound to have many common characteristics with the tornado vortices in nature, which sugges...

The Steiner tree problem

CERN Document Server

Hwang, FK; Winter, P

1992-01-01

The Steiner problem asks for a shortest network which spans a given set of points. Minimum spanning networks have been well-studied when all connections are required to be between the given points. The novelty of the Steiner tree problem is that new auxiliary points can be introduced between the original points so that a spanning network of all the points will be shorter than otherwise possible. These new points are called Steiner points - locating them has proved problematic and research has diverged along many different avenues. This volume is devoted to the assimilation of the rich field of intriguing analyses and the consolidation of the fragments. A section has been given to each of the three major areas of interest which have emerged. The first concerns the Euclidean Steiner Problem, historically the original Steiner tree problem proposed by Jarník and Kössler in 1934. The second deals with the Steiner Problem in Networks, which was propounded independently by Hakimi and Levin and has enjoyed the most...

The major tokamak distruption in cylindrical plasma

International Nuclear Information System (INIS)

Choi, Jeong Sik; Choi, Eun Ha; Choi, Duk In

1986-01-01

The mechanism of the major disruption in tokamak plasma which involves the nonlinear interaction of tearing models is numerically studied in two and three dimensional formulations. In this study, it is found that in the two dimensional case with a flattened current density profile the magnetic islands of the m=2; n=1 mode do not saturate nonlinearly and but strongly interact with the limiter. Thus it is suggested that the helical perturbation of the m=2;n=1 mode plays the dominant role in the major disruption. We also show that the m=2;n=1 mode nonlinearly destablizes other tearing modes, especially the m=3;n=2 mode, from the nonlinear coupling of different helicities as also shown in other studies. The plasma extends across the plasma cross section, and the plasma core shifts inward along the major radius during the major disruption. The numerical result for the major disruption time measured using the nonlinear 3-D procedure for the initial value problem with PLT parameters is about 450 μsec which agrees reasonably well with the experimental value of 500 μsec. (Author)

A Computer Model of Simple Forms of Learning.

Science.gov (United States)

Jones, Thomas L.

A basic unsolved problem in science is that of understanding learning, the process by which people and machines use their experience in a situation to guide future action in similar situations. The ideas of Piaget, Pavlov, Hull, and other learning theorists, as well as previous heuristic programing models of human intelligence, stimulated this…

An inverse method for the design of TIR collimators to achieve a uniform color light beam

NARCIS (Netherlands)

Prins, C.R.; Thije Boonkkamp, ten J.H.M.; Tukker, T.W.; IJzerman, W.L.

2012-01-01

Color over Angle (CoA) variation in the light output of white LEDs is a common and unsolved problem. In this article we introduce a new method to reduce CoA variation using a special collimator. The method is based on analytical inverse design methods. We present a numerical algorithm to solve the

An inverse method for the design of TIR collimators to achieve a uniform color light beam

NARCIS (Netherlands)

Prins, C.R.; Thije Boonkkamp, ten J.H.M.; Tukker, T.W.; IJzerman, W.L.

2013-01-01

Color-over-angle (CoA) variation in the light output of white LEDs is a common and unsolved problem. In this article we introduce a new method to reduce CoA variation using a special collimator. The method is based on analytical inverse design methods. We present a numerical algorithm to solve the

Epidemiology of major depressive disorder

OpenAIRE

Stegenga, B.T.

2011-01-01

Major depressive disorder (MDD) is a serious health problem and will be the second leading cause of burden of disease worldwide by 2030. To be able to prevent MDD, insight into risk factors for the onset of MDD is of clear importance. On the other hand, if onset of MDD has occurred, one may argue that different course patterns of MDD can be identified and that it is essential to examine their relationship to symptoms and function over time. Insight into these course patterns could assist in p...

Empowering Educationally Disadvantaged Mathematics Students through a Strategies-Based Problem Solving Approach

Science.gov (United States)

Ramnarain, Umesh

2014-01-01

A major impediment to problem solving in mathematics in the great majority of South African schools is that disadvantaged students from seriously impoverished learning environments are lacking in the necessary informal mathematical knowledge to develop their own strategies for solving non-routine problems. A randomized pretest-posttest control…

NASTRAN thermal analyzer: Theory and application including a guide to modeling engineering problems, volume 2. [sample problem library guide

Science.gov (United States)

Jackson, C. E., Jr.

1977-01-01

A sample problem library containing 20 problems covering most facets of Nastran Thermal Analyzer modeling is presented. Areas discussed include radiative interchange, arbitrary nonlinear loads, transient temperature and steady-state structural plots, temperature-dependent conductivities, simulated multi-layer insulation, and constraint techniques. The use of the major control options and important DMAP alters is demonstrated.

Managing Radioactive Waste. Problems and Challenges in a Globalizing World

International Nuclear Information System (INIS)

2010-09-01

Many countries are at a crossroads in terms of maintaining their energy supply. The existing resources of fossil fuels are dwindling, and global warming makes their use increasingly problematic. Nuclear power is now often regarded inevitable for future sustainability, energy security, and economic prosperity. There are, however, still unsolved problems regarding nuclear power. The fact that no country has established a final waste repository for spent nuclear fuel throws fundamental doubt on nuclear energy expansion. Also, the processes of globalization have transformed the nuclear industry towards increased privatization, concentration, and internationalization. This leads to uncertainties regarding the responsibility for nuclear waste management. In these circumstances is it of greatest importance that scholars from different disciplines, as well as policy makers and practitioners within the field, meet to share experiences. This conference had the general objective of producing knowledge about the challenges caused by global developmental trends, and what the management of nuclear waste implies for contemporary and future social development. Over 100 persons attended the conferences. Papers available at the conference site have been separately indexed. Several contributions were also made as PP-presentation, which are available at the site, among others the Keynote Speeches: Waiting for the Nuclear Renaissance: Exploring the Nexus of Expansion and Disposal in Europe (Jane Dawson); Applying the Risk Governance Framework: Institutional Requirements for Dealing with Nuclear Waste (Ortwin Renn); Learning to Listen: The Long Road to Legitimating Radioactive Waste Management Policies (Frans Berkhout); The Nuclear Waste Debate is Irrational but We Need Not Panic (Frank von Hippel). The conference was divided into the following sessions: Session A: Political characteristics matters; Session B: Radioactivity, geology, society. On a problem definition of HLW

Managing Radioactive Waste. Problems and Challenges in a Globalizing World

Energy Technology Data Exchange (ETDEWEB)

2010-09-15

Many countries are at a crossroads in terms of maintaining their energy supply. The existing resources of fossil fuels are dwindling, and global warming makes their use increasingly problematic. Nuclear power is now often regarded inevitable for future sustainability, energy security, and economic prosperity. There are, however, still unsolved problems regarding nuclear power. The fact that no country has established a final waste repository for spent nuclear fuel throws fundamental doubt on nuclear energy expansion. Also, the processes of globalization have transformed the nuclear industry towards increased privatization, concentration, and internationalization. This leads to uncertainties regarding the responsibility for nuclear waste management. In these circumstances is it of greatest importance that scholars from different disciplines, as well as policy makers and practitioners within the field, meet to share experiences. This conference had the general objective of producing knowledge about the challenges caused by global developmental trends, and what the management of nuclear waste implies for contemporary and future social development. Over 100 persons attended the conferences. Papers available at the conference site have been separately indexed. Several contributions were also made as PP-presentation, which are available at the site, among others the Keynote Speeches: Waiting for the Nuclear Renaissance: Exploring the Nexus of Expansion and Disposal in Europe (Jane Dawson); Applying the Risk Governance Framework: Institutional Requirements for Dealing with Nuclear Waste (Ortwin Renn); Learning to Listen: The Long Road to Legitimating Radioactive Waste Management Policies (Frans Berkhout); The Nuclear Waste Debate is Irrational but We Need Not Panic (Frank von Hippel). The conference was divided into the following sessions: Session A: Political characteristics matters; Session B: Radioactivity, geology, society. On a problem definition of HLW

Assessment of computer-related health problems among post-graduate nursing students.

Science.gov (United States)

Khan, Shaheen Akhtar; Sharma, Veena

2013-01-01

The study was conducted to assess computer-related health problems among post-graduate nursing students and to develop a Self Instructional Module for prevention of computer-related health problems in a selected university situated in Delhi. A descriptive survey with co-relational design was adopted. A total of 97 samples were selected from different faculties of Jamia Hamdard by multi stage sampling with systematic random sampling technique. Among post-graduate students, majority of sample subjects had average compliance with computer-related ergonomics principles. As regards computer related health problems, majority of post graduate students had moderate computer-related health problems, Self Instructional Module developed for prevention of computer-related health problems was found to be acceptable by the post-graduate students.

Food Security Problems in Borabu Division, Nyamira District ...

African Journals Online (AJOL)

Food Security Problems in Borabu Division, Nyamira District. ... Finally, the paper highlights some of the major problems associated with land use for instance, labour shortages, lack of credit facilities, type of farm implements used, overutilization of land, limited extension services, and extinction of indigenous crops. Last but ...

^{7}Be(n,α)^{4}He Reaction and the Cosmological Lithium Problem: Measurement of the Cross Section in a Wide Energy Range at n_TOF at CERN.

Science.gov (United States)

Barbagallo, M; Musumarra, A; Cosentino, L; Maugeri, E; Heinitz, S; Mengoni, A; Dressler, R; Schumann, D; Käppeler, F; Colonna, N; Finocchiaro, P; Ayranov, M; Damone, L; Kivel, N; Aberle, O; Altstadt, S; Andrzejewski, J; Audouin, L; Bacak, M; Balibrea-Correa, J; Barros, S; Bécares, V; Bečvář, F; Beinrucker, C; Berthoumieux, E; Billowes, J; Bosnar, D; Brugger, M; Caamaño, M; Calviani, M; Calviño, F; Cano-Ott, D; Cardella, R; Casanovas, A; Castelluccio, D M; Cerutti, F; Chen, Y H; Chiaveri, E; Cortés, G; Cortés-Giraldo, M A; Cristallo, S; Diakaki, M; Domingo-Pardo, C; Dupont, E; Duran, I; Fernandez-Dominguez, B; Ferrari, A; Ferreira, P; Furman, W; Ganesan, S; García-Rios, A; Gawlik, A; Glodariu, T; Göbel, K; Gonçalves, I F; González-Romero, E; Griesmayer, E; Guerrero, C; Gunsing, F; Harada, H; Heftrich, T; Heyse, J; Jenkins, D G; Jericha, E; Katabuchi, T; Kavrigin, P; Kimura, A; Kokkoris, M; Krtička, M; Leal-Cidoncha, E; Lerendegui, J; Lederer, C; Leeb, H; Lo Meo, S; Lonsdale, S J; Losito, R; Macina, D; Marganiec, J; Martínez, T; Massimi, C; Mastinu, P; Mastromarco, M; Mazzone, A; Mendoza, E; Milazzo, P M; Mingrone, F; Mirea, M; Montesano, S; Nolte, R; Oprea, A; Pappalardo, A; Patronis, N; Pavlik, A; Perkowski, J; Piscopo, M; Plompen, A; Porras, I; Praena, J; Quesada, J; Rajeev, K; Rauscher, T; Reifarth, R; Riego-Perez, A; Rout, P; Rubbia, C; Ryan, J; Sabate-Gilarte, M; Saxena, A; Schillebeeckx, P; Schmidt, S; Sedyshev, P; Smith, A G; Stamatopoulos, A; Tagliente, G; Tain, J L; Tarifeño-Saldivia, A; Tassan-Got, L; Tsinganis, A; Valenta, S; Vannini, G; Variale, V; Vaz, P; Ventura, A; Vlachoudis, V; Vlastou, R; Vollaire, J; Wallner, A; Warren, S; Weigand, M; Weiß, C; Wolf, C; Woods, P J; Wright, T; Žugec, P

2016-10-07

The energy-dependent cross section of the ^{7}Be(n,α)^{4}He reaction, of interest for the so-called cosmological lithium problem in big bang nucleosynthesis, has been measured for the first time from 10 meV to 10 keV neutron energy. The challenges posed by the short half-life of ^{7}Be and by the low reaction cross section have been overcome at n_TOF thanks to an unprecedented combination of the extremely high luminosity and good resolution of the neutron beam in the new experimental area (EAR2) of the n_TOF facility at CERN, the availability of a sufficient amount of chemically pure ^{7}Be, and a specifically designed experimental setup. Coincidences between the two alpha particles have been recorded in two Si-^{7}Be-Si arrays placed directly in the neutron beam. The present results are consistent, at thermal neutron energy, with the only previous measurement performed in the 1960s at a nuclear reactor. The energy dependence reported here clearly indicates the inadequacy of the cross section estimates currently used in BBN calculations. Although new measurements at higher neutron energy may still be needed, the n_TOF results hint at a minor role of this reaction in BBN, leaving the long-standing cosmological lithium problem unsolved.

Problems pilots face involving wind shear

Science.gov (United States)

Melvin, W. W.

1977-01-01

Educating pilots and the aviation industry about wind shears presents a major problem associated with this meteorological phenomenon. The pilot's second most pressing problem is the need for a language to discuss wind shear encounters with other pilots so that the reaction of the aircraft to the wind shear encounter can be accurately described. Another problem is the flight director which gives a centered pitch command for a given angular displacement from the glide slope. It was suggested that they should instead be called flight path command and should not center unless the aircraft is actually correcting to the flight path.

Fulltext PDF

Indian Academy of Sciences (India)

the outstanding unsolved problems in number theory is to prove (or disprove) that there are infinitely many twin ... point reciprocals (the ultra-precision reciprocals were also in error, by a lesser amount, evi- dently due to a ... Finally the source of the error was traced to the division algorithm implemented on the. Pentium chip.

Problems and prospects of refuse disposal in nigerian urban centres ...

African Journals Online (AJOL)

Refuse disposal is one of the major environmental problems that developing ... The problem of waste management has two parts, that of collection and that of disposal. ... Disposal methods such as dumping sites, incineration, recycling, shipping ... citizenry has roles to play in adopting more suitable solutions to this problem.

Video interview with Michael Dell

CERN Multimedia

CERN Bulletin

2010-01-01

Michael Dell, founder and presently Chairman of the Board of Directors and Chief Executive Office of the DELL computer company visited CERN on Tuesday 26th January 2010. The Bulletin and the Video productions team had the opportunity to meet him. The video interview is transcribed for your convenience.   Michael S. Dell with CERN Director-General Rolf Heuer. What motivated you to come and visit CERN? I obviously heard about the great science and research has going on here, and DELL is very pleased to be a partner and providing a lot of the computers to analyse the data and I really wanted to see for myself in person, some of the great science that is going on here. What is your view on fundamental research in IT, and in general? I think if you look at the field of science in the last hundred years, we have been able to solve a lot of problems, but there are still lots of unsolved problems and unsolved mysteries. And it is only through basic fundamental research that we will address these probl...

A Module-Based Environmental Science Course for Teaching Ecology to Non-Majors

Science.gov (United States)

Smith, Geoffrey R.

2010-01-01

Using module-based courses has been suggested to improve undergraduate science courses. A course based around a series of modules focused on major environmental issues might be an effective way to teach non-science majors about ecology and ecology's role in helping to solve environmental problems. I have used such a module-based environmental…

The efficacy of moisture retentive ointment in the mangement of cutaneous wounds and ulcers: A multicenter clinical trial

OpenAIRE

Atiyeh B; Ioannovich J; Magliacani G; Masellis M; Costagliola M; Dham R

2003-01-01

Local management of chronic wounds and ulcers remains one of the most costly unsolved problems in health care today. With proper clinical management, most chronic wound healing problems can be resolved and healing expected, though recurrence may be common. The recent logarithmic growth in our knowledge about wound healing and the appreciation of the importance of a moist environment in optimal wound healing has led to the introduction of new and exciting therapeutic modalities. In view of the...

The Animal Model of Spinal Cord Injury as an Experimental Pain Model

OpenAIRE

Nakae, Aya; Nakai, Kunihiro; Yano, Kenji; Hosokawa, Ko; Shibata, Masahiko; Mashimo, Takashi

2011-01-01

Pain, which remains largely unsolved, is one of the most crucial problems for spinal cord injury patients. Due to sensory problems, as well as motor dysfunctions, spinal cord injury research has proven to be complex and difficult. Furthermore, many types of pain are associated with spinal cord injury, such as neuropathic, visceral, and musculoskeletal pain. Many animal models of spinal cord injury exist to emulate clinical situations, which could help to determine common mechanisms of patholo...

Superconductive energy storage magnet study

International Nuclear Information System (INIS)

Rhee, S.W.

1982-01-01

Among many methods of energy storages the superconducting energy storage has been considered as the most promising method. Many related technical problems are still unsolved. One of the problems is the magnetizing and demagnetizing loss of superconducting coil. This loss is mainly because of hysteresis of pinning force. In this paper the hysteresis loss is calculated and field dependence of the a.c. losses is explained. The ratio of loss and stored energy is also calculated. (Author)

Understanding Subgroups of Novice Drivers : A Basis for Increased Safety and Health

OpenAIRE

Berg, Hans-Yngve

2001-01-01

Every year, drivers throughout the world are killed or injured in road traffic, particularly in developing countries. Young drivers run a greater risk everywhere, and this problem is still largely unsolved. Better understanding of the underlying processes could, however, be a useful tool in preventive endeavours. The aim of this thesis is to elucidate some of the accident problem among young car drivers. The focus is on understanding how lifestyle and other social and demographical factors in...

Prävalenz von Erkrankungen am Bewegungsapparat bei Sicherheitsschuhträgern

OpenAIRE

Loch, Stefanie

2003-01-01

The goal of this pilot study was to determine how often safety shoe wearers developed problems of the locomotor system. Background: In many lines of work, employees need a well-functioning musculoskeletal system in order to do their job properly. Disorders of the locomotor system, especially in fields where employees do mainly physical work (and therefore relies heavily on their musculoskeletal system), remain an unsolved problem to this day. Back pain develops due to a number of factors. Ris...

Iron deficiency - a global problem

International Nuclear Information System (INIS)

Ali, S.M.

1993-01-01

Iron deficiency is an important nutritional global problem. This paper contains summery of information gathered from a dietary survey as iron deficiency anaemia is major public health problem in many developing countries including Pakistan. Comparison of anaemia in different age group and sex versus various regions in the world are given. In Pakistan also anaemia is widespread. According to the report of Micro-Nutrient survey of Pakistan 40% of the population are found to have low level of haemoglobin, more than half of pregnant women suffered from marginal or deficient haemoglobin. (A.B.)

Iron deficiency - a global problem

Energy Technology Data Exchange (ETDEWEB)

Ali, S M [Pakistan Council for Science and Technology, Islamabad (Pakistan)

1994-12-31

Iron deficiency is an important nutritional global problem. This paper contains summery of information gathered from a dietary survey as iron deficiency anaemia is major public health problem in many developing countries including Pakistan. Comparison of anaemia in different age group and sex versus various regions in the world are given. In Pakistan also anaemia is widespread. According to the report of Micro-Nutrient survey of Pakistan 40% of the population are found to have low level of haemoglobin, more than half of pregnant women suffered from marginal or deficient haemoglobin. (A.B.).

Elliptic Tales Curves, Counting, and Number Theory

CERN Document Server

Ash, Avner

2012-01-01

Elliptic Tales describes the latest developments in number theory by looking at one of the most exciting unsolved problems in contemporary mathematics--the Birch and Swinnerton-Dyer Conjecture. The Clay Mathematics Institute is offering a prize of 1 million to anyone who can discover a general solution to the problem. In this book, Avner Ash and Robert Gross guide readers through the mathematics they need to understand this captivating problem. The key to the conjecture lies in elliptic curves, which are cubic equations in two variables. These equations may appear simple, yet they arise from

Globally Optimal Segmentation of Permanent-Magnet Systems

DEFF Research Database (Denmark)

Insinga, Andrea Roberto; Bjørk, Rasmus; Smith, Anders

2016-01-01

Permanent-magnet systems are widely used for generation of magnetic fields with specific properties. The reciprocity theorem, an energy-equivalence principle in magnetostatics, can be employed to calculate the optimal remanent flux density of the permanent-magnet system, given any objective...... remains unsolved. We show that the problem of optimal segmentation of a two-dimensional permanent-magnet assembly with respect to a linear objective functional can be reduced to the problem of piecewise linear approximation of a plane curve by perimeter maximization. Once the problem has been cast...

Vanpooling: the three major approaches

Energy Technology Data Exchange (ETDEWEB)

Sears, P.M.

1979-08-01

The manual provides technical assistance to existing or prospective vanpool sponsors. It is designed to help them promote vanpooling in its three major approaches: employer sponsored, third party sponsored, and driver owned and operated. The first chapter is an overview of vanpooling and a second chapter, on vanpool marketing, is addressed to ridesharing coordinators and others whose responsibilities include the promotion of vanpooling. Some fact sheets on the three approaches provide convenient summaries of the needs and opportunities of each approach and suggest solutions to practical problems likely to be encountered in starting new vanpool programs.

Major life events and risk of alcohol use disorders

DEFF Research Database (Denmark)

Just-Østergaard, Emilie; Mortensen, Erik L.; Flensborg-Madsen, Trine

2018-01-01

, household income, cohabitation status and psychiatric comorbidity. Findings: Serious family conflicts in childhood [hazard ratio (HR) = 1.35; 95% confidence interval (CI) = 1.00, 1.83] and serious economic problems in adult life (HR = 2.22; 95% CI = 1.64, 3.01) were associated significantly with increased......Aims: To estimate associations of individual major life events as well as accumulated major life events in childhood, adult private life and adult work life with risk of alcohol use disorders (AUD). Design: Prospective cohort study with baseline examination in 1991–93 and linkage to national...

Reasoning by analogy as an aid to heuristic theorem proving.

Science.gov (United States)

Kling, R. E.

1972-01-01

When heuristic problem-solving programs are faced with large data bases that contain numbers of facts far in excess of those needed to solve any particular problem, their performance rapidly deteriorates. In this paper, the correspondence between a new unsolved problem and a previously solved analogous problem is computed and invoked to tailor large data bases to manageable sizes. This paper outlines the design of an algorithm for generating and exploiting analogies between theorems posed to a resolution-logic system. These algorithms are believed to be the first computationally feasible development of reasoning by analogy to be applied to heuristic theorem proving.

Short-Term fo F2 Forecast: Present Day State of Art

Science.gov (United States)

Mikhailov, A. V.; Depuev, V. H.; Depueva, A. H.

An analysis of the F2-layer short-term forecast problem has been done. Both objective and methodological problems prevent us from a deliberate F2-layer forecast issuing at present. An empirical approach based on statistical methods may be recommended for practical use. A forecast method based on a new aeronomic index (a proxy) AI has been proposed and tested over selected 64 severe storm events. The method provides an acceptable prediction accuracy both for strongly disturbed and quiet conditions. The problems with the prediction of the F2-layer quiet-time disturbances as well as some other unsolved problems are discussed

Chemistry I and Clothing, Textiles and Fashion Merchandising Majors.

Science.gov (United States)

Clausen, Donald F.

1980-01-01

The application of principles learned in a first course in chemistry to chemical problems of interest to home economics majors specializing in clothing and textiles or fashion merchandising is described. Concept transfer--teaching difficult concepts in terms of an everyday analogue--is also explained and relevant laboratory experiments are…

Autoclave reduction of jarosites and other metal sulfates : a new approach to major waste problems

NARCIS (Netherlands)

Hage, J.T.L.

1999-01-01

Industrial jarosite is a waste product of the zinc industry. It is considered a serious environmental problem, due to the quantity produced and the mobile hazardous metals it contains. Over 50 million tons are already stored worldwide. The jarosite sludge autoclave treatment process described in

International Environmental Problems, Issue Linkage and the European Union

NARCIS (Netherlands)

Kroeze-Gil, J.

2003-01-01

This thesis explores the circumstances under which issue linkage can be applied to achieve cooperation on international environmental problems in general and on environmental problems in the European Union in particular. A major topic in this thesis is the development and analysis of cooperative and

8-EEASA-Vol 22.indd

African Journals Online (AJOL)

jenny

2006-02-22

Feb 22, 2006 ... My aim here is to introduce the concept of musement (retroduction ... unsolvable ethical problems in the use of IK in environmental education ... culture' is life threatening when it is used to deny women the right to insist that their partners wear ..... 12 For a critique of the relativism of some epistemologies with ...

Language of Physics, Language of Math: Disciplinary Culture and Dynamic Epistemology

Science.gov (United States)

Redish, Edward F.; Kuo, Eric

2015-01-01

Mathematics is a critical part of much scientific research. Physics in particular weaves math extensively into its instruction beginning in high school. Despite much research on the learning of both physics and math, the problem of how to effectively include math in physics in a way that reaches most students remains unsolved. In this paper, we…

Ensemble approach combining multiple methods improves human transcription start site prediction.

LENUS (Irish Health Repository)

Dineen, David G

2010-01-01

The computational prediction of transcription start sites is an important unsolved problem. Some recent progress has been made, but many promoters, particularly those not associated with CpG islands, are still difficult to locate using current methods. These methods use different features and training sets, along with a variety of machine learning techniques and result in different prediction sets.

Constraining the evolution of the Hubble Parameter using cosmic chronometers

Science.gov (United States)

Dickinson, Hugh

2017-08-01

Substantial investment is being made in space- and ground-based missions with the goal of revealing the nature of the observed cosmic acceleration. This is one of the most important unsolved problems in cosmology today.We propose here to constrain the evolution of the Hubble parameter [H(z)] between 1.3 fundamental nature of dark energy.

Electrocatalytic glucose sensor

Energy Technology Data Exchange (ETDEWEB)

Gebhardt, U; Luft, G; Mund, K; Preidel, W; Richter, G J

1983-01-01

An artificial pancreas consists of an insulin depot, a dosage unit and a glucose sensor. The measurement of the actual glucose concentration in blood is still an unsolved problem. Two methods are described for an electrocatalytic glucose sensor. Under the interfering action of amino acids and urea in-vitro measurements show an error of between 10% and 20%.

A road safety information system : from concept to implementation. Contribution to the Road Safety Training Course of the World Bank, 1 May 2001, Washington, D.C.

NARCIS (Netherlands)

Wegman, F.C.M.

2001-01-01

It is a proven fact that road safety problems are not unsolvable: what is man-made can also be unmade by man. This leads to questions such as which priorities to set, which measures to take, which effects to expect, what costs are involved, and how these can be financed. In order to be able to

The Galactic magnetic fields

International Nuclear Information System (INIS)

Han Jinlin

2006-01-01

A good progress has been made on studies of Galactic magnetic fields in last 10 years. I describe what we want to know about the Galactic magnetic fields, and then review we current knowledge about magnetic fields in the Galactic disk, the Galactic halo and the field strengths. I also listed many unsolved problems on this area

Biomedical engineering strategies in system design space.

Science.gov (United States)

Savageau, Michael A

2011-04-01

Modern systems biology and synthetic bioengineering face two major challenges in relating properties of the genetic components of a natural or engineered system to its integrated behavior. The first is the fundamental unsolved problem of relating the digital representation of the genotype to the analog representation of the parameters for the molecular components. For example, knowing the DNA sequence does not allow one to determine the kinetic parameters of an enzyme. The second is the fundamental unsolved problem of relating the parameters of the components and the environment to the phenotype of the global system. For example, knowing the parameters does not tell one how many qualitatively distinct phenotypes are in the organism's repertoire or the relative fitness of the phenotypes in different environments. These also are challenges for biomedical engineers as they attempt to develop therapeutic strategies to treat pathology or to redirect normal cellular functions for biotechnological purposes. In this article, the second of these fundamental challenges will be addressed, and the notion of a "system design space" for relating the parameter space of components to the phenotype space of bioengineering systems will be focused upon. First, the concept of a system design space will be motivated by introducing one of its key components from an intuitive perspective. Second, a simple linear example will be used to illustrate a generic method for constructing the design space in which qualitatively distinct phenotypes can be identified and counted, their fitness analyzed and compared, and their tolerance to change measured. Third, two examples of nonlinear systems from different areas of biomedical engineering will be presented. Finally, after giving reference to a few other applications that have made use of the system design space approach to reveal important design principles, some concluding remarks concerning challenges and opportunities for further development

Radiation analysis in the major areas of marine fisheries research

International Nuclear Information System (INIS)

Murty, A.V.S.

1975-01-01

Radiation analysis has been a proven technique to solve, relatively easily and quickly, some of the pressing problems in marine fisheries to the utmost satisfaction. Major areas of marine fisheries research - namely, the determination of sea water characteristics, the productivity studies, the pollution effects, the population dynamics and the preservation of sea foods - wherein the radiation treatment is fully helpful are discussed in detail. The problems encountered in the marine fisheries in India in this context are also outlined. (author)

Exposure to cosmic radiation: a developing major problem in radiation protection

International Nuclear Information System (INIS)

Lowder, W.M.; Hajnal, F.

1992-01-01

'Full Text:' Cosmic radiation at ground altitudes is usually a relatively minor contributor to human radiation exposure, producing a global collective dose equivalent that is about 10 percent of the total from all natural sources. However, more than a million people living at high altitudes receive annual dose equivalents in excess of 5 mSv. In recent years, there has been increasing concern about the exposure of aircraft flight crews and passengers, for whom annual dose equivalents of up to several mSv have been estimated. Recent EML results indicate the presence of an important high-energy neutron component at jet aircraft altitudes, perhaps producing dose equivalents of the order of 0.1. mSv/h at high latitudes. Finally, space agencies have been long concerned with the potential exposures of astronauts, especially from the rare massive solar flare events. As more people venture into space, this source of human radiation exposure will become increasingly important. Available date on those aspects of cosmic radiation exposure will be reviewed, along with current and anticipated future research activities that may yield and improve assessment of the problem. The question of how such exposures might be controlled will be addressed, but not answered. (author)

High expression of microRNA-625-3p is associated with poor response to first-line oxaliplatin based treatment of metastatic colorectal cancer

DEFF Research Database (Denmark)

Rasmussen, Mads Heilskov; Jensen, Niels; Tarpgaard, Line Schmidt

2013-01-01

The backbone of current cytotoxic treatment of metastatic colorectal cancer (mCRC) consists of a fluoropyrimidine together with either oxaliplatin (XELOX/FOLFOX) or irinotecan (XELIRI/FOLFIRI). With an overall objective response rate of approximately 50% for either treatment combination, a major...... analyses showed that miR-625-3p was not dysregulated between normal and cancer samples, nor was its expression associated with recurrence of stage II or III disease, indicating that miR-625-3p solely is a response marker. Finally, we also found that these miRNAs were up-regulated in oxaliplatin resistant...... unsolved problem is that no predictors of response to these treatments are available. To address this issue, we profiled 742 microRNAs in laser-capture microdissected cancer cells from responding and non-responding patients receiving XELOX/FOLFOX as first-line treatment for mCRC, and identified, among...

Theory of the Origin, Evolution, and Nature of Life

Directory of Open Access Journals (Sweden)

Erik D. Andrulis

2011-12-01

Full Text Available Life is an inordinately complex unsolved puzzle. Despite significant theoretical progress, experimental anomalies, paradoxes, and enigmas have revealed paradigmatic limitations. Thus, the advancement of scientific understanding requires new models that resolve fundamental problems. Here, I present a theoretical framework that economically fits evidence accumulated from examinations of life. This theory is based upon a straightforward and non-mathematical core model and proposes unique yet empirically consistent explanations for major phenomena including, but not limited to, quantum gravity, phase transitions of water, why living systems are predominantly CHNOPS (carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur, homochirality of sugars and amino acids, homeoviscous adaptation, triplet code, and DNA mutations. The theoretical framework unifies the macrocosmic and microcosmic realms, validates predicted laws of nature, and solves the puzzle of the origin and evolution of cellular life in the universe.

Indoor air problems in Asia

International Nuclear Information System (INIS)

Leslie, G.B.

1995-01-01

Respiratory disease and mortality due to indoor air pollution are amongst the greatest environmental threats to health in the developing countries of Asia. World-wide, acute respiratory infection is the cause of death of at least 5 million children under the age of 5 every year. The World Bank has claimed that smoke from biomass fuels resulted in an estimated 4 million deaths annually amongst infants and children. Most of these deaths occur in developing countries. Combustion in its various forms must head the list of pollution sources in Asia. Combustion of various fuels for domestic heating, lighting and cooking comprises the major source of internally generated pollutants and combustion in industrial plants, power generation and transportation is the major cause of externally generated pollutants. The products of pyrolysis and combustion include many compounds with well-known adverse health effects. These include gases such as CO, CO 2 , NO x and SO 2 , volatile organic compounds such as polynuclear aromatic hydrocarbons and nitroamines as well as respirable particulates of variable composition. The nature and magnitude of the health risks posed by these materials vary with season, climate, location housing, method of ventilation, culture and socio-economic status. The most important cause of lung cancer in non-smokers in Northern Asia is the domestic combustion of smoky coal. Acute carbon monoxide poisoning is common in many Asian countries. Roads traffic exhaust pollution is worse in the major cities of South East Asia than almost anywhere else in the world and this externally generated air pollution forms the indoor air for the urban poor. Despite all these major problems there has been a tendency for international agencies to focus attention and resources on the more trivial problems of indoor air encountered in the affluent countries of the West. Regulatory agencies in Asia have been too frequently persuaded that their problems of indoor air pollution are

THE COMPATIBILITY STUDENT CHOICE OF UNIVERSITY MAJORING; A PRELIMINARY STUDIES

Directory of Open Access Journals (Sweden)

Daharnis Daharnis

2016-06-01

Full Text Available The continuous improvements in order to optimize the basic education to higher education are still running. Based on that purpose, there are many factors to supporting the students' learning activities success; one of the factors is suitability with majors in university. The purpose of this study is to reveal the condition of the compatibility of students majoring with their interest, then to describe the information when the student choose their majoring. Samples in this study were 122 peoples, taken by random sampling from the Padang State University. Data obtained by distributing questionnaires. The results showed that there are students that their major do not match with their interest (22.13%, only 3.28% of students who feel compatible with their major. This result should be a major concern, particularly for counselor in schools for design counseling services to solve these problems. The result of this study used as a grand tour or a preliminary study for further research.

Using qualitative problem-solving strategies to highlight the role of conceptual knowledge in solving problems

Science.gov (United States)

Leonard, William J.; Dufresne, Robert J.; Mestre, Jose P.

1996-12-01

We report on the use of qualitative problem-solving strategies in teaching an introductory, calculus-based physics course as a means of highlighting the role played by conceptual knowledge in solving problems. We found that presenting strategies during lectures and in homework solutions provides an excellent opportunity to model for students the type of concept-based, qualitative reasoning that is valued in our profession, and that student-generated strategies serve a diagnostic function by providing instructors with insights on students' conceptual understanding and reasoning. Finally, we found strategies to be effective pedagogical tools for helping students both to identify principles that could be applied to solve specific problems, as well as to recall the major principles covered in the course months after it was over.

The non-English major lecturers speak English: The barriers encountered by adult learners

Directory of Open Access Journals (Sweden)

Ahmad Madkur

2018-03-01

Full Text Available This study was aimed at investigating the difficulties and problems faced by non-English major lecturers when they were taking a part in English discussion. This study was a qualitative descriptive research involving 10 non-English major lecturers who took a part in a twice-a-week discussion so-called English Corner. To collect the data, in-depth interview and observation were used. The collected data were analyzed by using Miles and Huberman’s interactive data analysis data model consisting of data reduction, data display and data verifying. The result of the study showed that those barriers could be classified into three problems namely socio-cultural, linguistic and interpersonal problems. The found barriers were expected to be a consideration to find out the solution to make the betterment of English learning among lecturers with the non-English background of study.

Role of physical activity in preventing mental health problems

NARCIS (Netherlands)

Bernaards, C.

2006-01-01

Mental health problems are a major concern to employers, employees and occupational health professionals in the Netherlands. Employees developing these problems often have to take long-term leave from work, which may lead to disability. About a third of the total disability inflow is due to

The Problem of World Hunger.

Science.gov (United States)

Czarra, Fred R.; Long, Cathryn J., Eds.

1983-01-01

The major hunger problem today is chronic undernutrition, the primary cause of which is poverty. Hunger can be alleviated through food supplements, nutrition programs, and disaster relief. It can be eliminated by redistributing existing wealth and producing enough food and through equitable economic growth and a world food security system. (CS)

Prevalence of the Addictions: A Problem of the Majority or the Minority?

Science.gov (United States)

Sussman, Steve; Lisha, Nadra; Griffiths, Mark

2011-01-01

An increasing number of research studies over the last three decades suggest that a wide range of substance and process addictions may serve similar functions. The current article considers 11 such potential addictions (tobacco, alcohol, illicit drugs, eating, gambling, Internet, love, sex, exercise, work, and shopping), their prevalence, and co-occurrence, based on a systematic review of the literature. Data from 83 studies (each study n = at least 500 subjects) were presented and supplemented with small-scale data. Depending on which assumptions are made, overall 12-month prevalence of an addiction among U.S. adults varies from 15% to 61%. The authors assert that it is most plausible that 47% of the U.S. adult population suffers from maladaptive signs of an addictive disorder over a 12-month period and that it may be useful to think of addictions as due to problems of lifestyle as well as to person-level factors. PMID:20876085

The hematopoietic stem cell transplantation in Indonesia: an unsolved dilemma.

Science.gov (United States)

Hariman, H

2008-08-01

Allogeneic BMT was performed in Indonesia, but had to be stopped prematurely because of the small number of patients. In the beginning, only patients with sufficient financial resources to travel to western countries could undergo transplant procedures. When neighbouring countries (Singapore and Malaysia) began performing transplant, patients were referred to those centres. In both countries, the procedure is more economical and therefore patients come from a broader range of economic classes. The Indonesian hematologist must deal with the post-transplantation side effects, such as GVHD, which are mostly of the chronic type of GVHD. The types of the post-transplant complications do not differ too much from other centres and need the same treatment used in the transplant centres. Hematologists in Indonesia also treat complications of HSCT performed in other countries. When there is no recovery of HSCT development in Indonesia so far, many commercially oriented companies or centres from other countries see Indonesia as a good commercial market and offer services, some of which are not scientifically sound. One of the main problems is umbilical cord blood stem cell banking from foreign countries, which is eagerly offered to parents expecting a baby. Moreover, parents are not fully protected by law. In conclusion, Indonesia needs to revive its own HSCT program to serve and protect its own patients of being used as commercial targets by other countries.

Drying shrinkage problems in high-plastic clay soils in Oklahoma.

Science.gov (United States)

2013-08-01

Longitudinal cracking in pavements due to drying shrinkage of high-plastic subgrade soils has been a major : problem in Oklahoma. Annual maintenance to seal and repair these distress problems costs significant amount of : money to the state. The long...

Continuum capture in the three-body problem

International Nuclear Information System (INIS)

Sellin, I.A.

1980-01-01

The three-body problem, especially the problem of electron capture to the continuum in heavy particle collisions is reviewed. Major topics covered include: second born-induced asymmetry in electron capture to the continuum; historical context, links to other tests of atomic scattering theory; experiments characterizing the velocity distribution of ECC electrons; other atomic physics tests of high velocity Born expansions; atom capture; capture by positrons; and pion capture to the continuum

Life satisfaction and mental health problems (18 to 35 years).

Science.gov (United States)

Fergusson, D M; McLeod, G F H; Horwood, L J; Swain, N R; Chapple, S; Poulton, R

2015-08-01

Previous research has found that mental health is strongly associated with life satisfaction. In this study we examine associations between mental health problems and life satisfaction in a birth cohort studied from 18 to 35 years. Data were gathered during the Christchurch Health and Development Study, which is a longitudinal study of a birth cohort of 1265 children, born in Christchurch, New Zealand, in 1977. Assessments of psychiatric disorder (major depression, anxiety disorder, suicidality, alcohol dependence and illicit substance dependence) using DSM diagnostic criteria and life satisfaction were obtained at 18, 21, 25, 30 and 35 years. Significant associations (p life satisfaction and the psychiatric disorders major depression, anxiety disorder, suicidality, alcohol dependence and substance dependence. After adjustment for non-observed sources of confounding by fixed effects, statistically significant associations (p life satisfaction and major depression, anxiety disorder, suicidality and substance dependence. Overall, those reporting three or more mental health disorders had mean life satisfaction scores that were nearly 0.60 standard deviations below those without mental health problems. A structural equation model examined the direction of causation between life satisfaction and mental health problems. Statistically significant (p life satisfaction and mental health problems. After adjustment for confounding, robust and reciprocal associations were found between mental health problems and life satisfaction. Overall, this study showed evidence that life satisfaction influences mental disorder, and that mental disorder influences life satisfaction.

Beam dynamics problems for next generation linear colliders

International Nuclear Information System (INIS)

Yokoya, Kaoru

1990-01-01

The most critical issue for the feasibility of high-energy e + e - linear colliders is obviously the development of intense microwave power sources. Remaining problems, however, are not trivial and in fact some of them require several order-of-magnitude improvement from the existing SLC parameters. The present report summarizes the study status of the beam dynamics problems of high energy linear colliders with an exaggeration on the beam-beam phenomenon at the interaction region. There are four laboratories having linear collider plans, SLAC, CERN, Novosibirsk-Protovino, and KEK. The parameters of these projects scatter in some range but seem to converge slowly if one recalls the status five years ago. The beam energy will be below 500GeV. The basic requirements to the damping ring are the short damping time and small equilibrium emittance. All the proposed designs make use of tight focusing optics and strong wiggler magnets to meet these requirements and seem to have no major problems at least compared with other problems in the colliders. One of the major problems in the linac is the transverse beam blow-up due to the wake field created by the head of the bunch and, in the case of multiple bunches per pulse, by the preceeding bunches. (N.K.)

Problem Gambling on College Campuses

Science.gov (United States)

McComb, Jennifer L.; Hanson, William E.

2009-01-01

The vast majority of college students gamble, with some doing so problematically. This article discusses gambling and problem gambling among college students, framing it as an emerging health issue on college campuses nationwide. Given that 4 out of 5 college students admit to gambling, and that approximately 8% gamble problematically, it is…

The Pricing of Options on Assets with Stochastic Volatilities.

OpenAIRE

Hull, John C; White, Alan D

1987-01-01

One option-pricing problem which has hitherto been unsolved is the pricing of European call on an asset which has a stochastic volatility. This paper examines this problem. The option price is determined in series form for the case in which the stochastic volatility is independent of the stock price. Numerical solutions are also produced for the case in which the volatility is correlated with the stock price. It is found that the Black-Scholes price frequently overprices options and that the ...

Further retardation could lead to a hold-up of nuclear reactor dismantling; Weitere Verzoegerungen koennten zu einem Stillstand des Kernkraft-Rueckbaus fuehren

Energy Technology Data Exchange (ETDEWEB)

Graf, Konstantin (comp.) [Innovations- und Technologieberatung Altran, Frankfurt am Main (Germany). Bereich Energy and Industry

2015-07-01

The following issues concerning the consequences of the German nuclear power phaseout are discussed: the cost of reactor dismantling could increase; the complete deconstruction of a nuclear power plant including environmental revitalization take a time of 10-15 years; the largest challenge is the still unsolved problem of final disposal; further retardations could trigger a complete deadlock of the deconstruction due to completely filled interim storage facilities. A further problem is the knowledge preservation due to the lack of students.

Novel imaging strategies for upper gastrointestinal tract cancers

DEFF Research Database (Denmark)

Mortensen, Michael Bau

2015-01-01

Accurate pretherapeutic imaging is the cornerstone of all cancer treatment. Unfortunately, modern imaging modalities have several unsolved problems and limitations. The differentiation between inflammation and cancer infiltration, false positive and false negative findings as well as lack...... of confirming biopsies in suspected metastases may have serious negative consequences in cancer patients. This review describes some of these problems and challenges the use of conventional imaging by suggesting new combined strategies that include selective use of confirming biopsies and complementary methods...

Dynamical systems in classical mechanics

CERN Document Server

Kozlov, V V

1995-01-01

This book shows that the phenomenon of integrability is related not only to Hamiltonian systems, but also to a wider variety of systems having invariant measures that often arise in nonholonomic mechanics. Each paper presents unique ideas and original approaches to various mathematical problems related to integrability, stability, and chaos in classical dynamics. Topics include… the inverse Lyapunov theorem on stability of equilibria geometrical aspects of Hamiltonian mechanics from a hydrodynamic perspective current unsolved problems in the dynamical systems approach to classical mechanics

Problem of Information Security Traffic on Internet

Directory of Open Access Journals (Sweden)

Slavko Šarić

2012-10-01

Full Text Available Internet information traffic becomes greater and moreimportant. With increasing growth of information importancerequirement for its security becomes indispensable. Theinformation security problem especially affect large and smallcompanies whose prosperity is depending on Internet presence.This affecting the three areas of Internet commerce: credit cardtransactions, virtual private networks and digital certification.To ensure information traffic it is necessary to find a solution,in a proper way, for three major problems: frontier problem,market problem and government problem. While the eventualemergence of security standards for Internet transactions isexpected, it will not automatically result in secure Internettransactions. In future, there is a wealth of security issues thatwill continue to require attention: internal security, continuedhacking, social engineering, malicious code, reliability andperformance, skills shortages and denial of se1vice attacks.

A Review on Polymer Crystallization Theories

Directory of Open Access Journals (Sweden)

Michael C. Zhang

2016-12-01

Full Text Available It is the aim of this article to review the major theories of polymer crystallization since up to now we still have not completely comprehended the underlying mechanism in a unified framework. A lack of paradigm is an indicator of immaturity of the field itself; thus, the fundamental issue of polymer crystallization remains unsolved. This paper provides an understanding of the basic hypothesis, as well as relevant physical implications and consequences of each theory without too much bias. We try to present the essential aspects of the major theories, and intuitive physical arguments over rigorously mathematical calculations are highlighted. In addition, a detailed comparison of various theories will be made in a logical and self-contained fashion. Our personal view of the existing theories is presented as well, aiming to inspire further open discussions. We expect that new theories based on the framework of kinetics with direct consideration of long-range multi-body correlation will help solve the remaining problems in the field of polymer crystallization.

Iron in seeds – loading pathways and subcellular localization

Directory of Open Access Journals (Sweden)

Louis eGrillet

2014-01-01

Full Text Available Iron (Fe is one of the most abundant elements on earth, but its limited bioavailability poses a major constraint for agriculture and constitutes a serious problem in human health. Due to an improved understanding of the mechanisms that control Fe homeostasis in plants, major advances towards engineering biofortified crops have been made during the past decade. Examples of successful biofortification strategies are, however, still scarce and the process of Fe loading into seeds is far from being well understood in most crop species. In particular in grains where the embryo represents the main storage compartment such as legumes, increasing the seed Fe content remains a challenging task. This review aims at placing the recently identified actors in Fe transport into the unsolved puzzle of grain filling, taking the differences of Fe distribution between various species into consideration. We summarize the current knowledge on Fe transport between symplasmic and apoplasmic compartments, and provide models for Fe trafficking and localization in different seed types that may help to develop high seed Fe germplasms.

Basic math and pre-algebra practice problems for dummies

CERN Document Server

Zegarelli, Mark

2013-01-01

1001 Basic Math & Pre- Algebra Practice Problems For  Dummies   Practice makes perfect-and helps deepen your understanding of basic math and pre-algebra 1001 Basic Math & Pre-Algebra Practice Problems For Dummies, with free access to online practice problems, takes you beyond the instruction and guidance offered in Basic Math & Pre-Algebra For Dummies, giving you 1,001 opportunities to practice solving problems from the major topics in your math course. You begin with some basic arithmetic practice, move on to fractions, decimals, and per

[Problems resulting from the absorption of small towns into urban areas in major Third World cities].

Science.gov (United States)

Mckee, D L

1985-01-01

The tendency toward hypertrophy of large metropolitan areas in the Third World has been a subject of concern to economists and other social scientists for some time. Inability to absorb vast waves of migrants into the organized labor force or to provide adequate infrastructure and services are serious problems in many growing cities of Asia, Africa, and Latin America. A different phenomenon created by perpetual urban expansion has been relatively neglected: the problems caused when preexisting urban areas are absorbed into the metropolis. The tendency of squatter settlements to constrict normal urban growth and expansion and to impede rational provision of services has been recognized, but the absorption of small cities does not necessarily produce identical problems. Small cities absorbed into a metropolis lose their identity in the successive waves of suburban proliferation. Los Angeles in the US may be considered the prototype of the phenomenon in which multiple preexisting urban zones are absorbed into the same metropolis without formation of any visible center of gravity. In some cases, small cities may be completely engulfed by the encroaching metropolis, if transit routes or availability of land makes them interesting to developers. The livelihood of residents may be threatened if they are no longer able to cultivate gardens or raise small animals. Local services may deteriorate. The youngest and most able residents are likely to abandon such places for the greater opportunities of the city, leaving the aged and less qualified to fend for themselves. Jobs may disappear and traditional commercial relations may be destroyed without being replaced. The future wellbeing of residents depends on their ability to maneuver in the new metropolitan environment, but many will be unable to adjust for lack of training, the weight of immovable property, or diverse personal considerations. Planning could help to reduce the problems that occasional survival of some small

Developing and Evaluating Medical Humanities Problem-Based Learning Classes Facilitated by the Teaching Assistants Majored in the Liberal Arts

Science.gov (United States)

Tseng, Fen-Yu; Shieh, Jeng-Yi; Kao, Tze-Wah; Wu, Chau-Chung; Chu, Tzong-Shinn; Chen, Yen-Yuan

2016-01-01

Abstract Although medical humanities courses taught by teachers from nonmedical backgrounds are not unusual now, few studies have compared the outcome of medical humanities courses facilitated by physicians to that by teaching assistants majored in the liberal arts. The objectives of this study were to (1) analyze the satisfaction of medical students with medical humanities problem-based learning (PBL) classes facilitated by nonmedical teaching assistants (TAF) majored in the liberal arts, and those facilitated by the attending physicians (APF) and (2) examine the satisfaction of medical students with clinical medicine-related and clinical medicine-unrelated medical humanities PBL classes. A total of 123 medical students, randomly assigned to 16 groups, participated in this study. There were 16 classes in the course: 8 of them were TAF classes; and the others were APF classes. Each week, each group rotated from 1 subject of the 16 subjects of PBL to another subject. All of the 16 groups went through all the 16 subjects in the 2013 spring semester. We examined the medical students’ satisfaction with each class, based on a rating score collected after each class was completed, using a scale from 0 (the lowest satisfaction) to 100 (the highest satisfaction). We also conducted multivariate linear regression analysis to examine the association between the independent variables and the students’ satisfaction. Medical students were more satisfied with the TAF (91.35 ± 7.75) medical humanities PBL classes than APF (90.40 ± 8.42) medical humanities PBL classes (P = 0.01). Moreover, medical students were more satisfied with the clinical medicine-unrelated topics (92.00 ± 7.10) than the clinical medicine-related topics (90.36 ± 7.99) in the medical humanities PBL course (P = 0.01). This medical humanities PBL course, including nonmedical subjects and topics, and nonmedical teaching assistants from the liberal arts as class facilitators, was

Numerical solutions of the N-body problem

International Nuclear Information System (INIS)

Marciniak, A.

1985-01-01

Devoted to the study of numerical methods for solving the general N-body problem and related problems, this volume starts with an overview of the conventional numerical methods for solving the initial value problem. The major part of the book contains original work and features a presentation of special numerical methods conserving the constants of motion in the general N-body problem and methods conserving the Jacobi constant in the problem of motion of N bodies in a rotating frame, as well as an analysis of the applications of both (conventional and special) kinds of methods for solving these problems. For all the methods considered, the author presents algorithms which are easily programmable in any computer language. Moreover, the author compares various methods and presents adequate numerical results. The appendix contains PL/I procedures for all the special methods conserving the constants of motion. 91 refs.; 35 figs.; 41 tabs

Shutdown problems in large tokamaks

International Nuclear Information System (INIS)

Weldon, D.M.

1978-01-01

Some of the problems connected with a normal shutdown at the end of the burn phase (soft shutdown) and with a shutdown caused by disruptive instability (hard shutdown) have been considered. For a soft shutdown a cursory literature search was undertaken and methods for controlling the thermal wall loading were listed. Because shutdown computer codes are not widespread, some of the differences between start-up codes and shutdown codes were discussed along with program changes needed to change a start-up code to a shutdown code. For a hard shutdown, the major problems are large induced voltages in the ohmic-heating and equilibrium-field coils and high first wall erosion. A literature search of plasma-wall interactions was carried out. Phenomena that occur at the plasma-wall interface can be quite complicated. For example, material evaporated from the wall can form a virtual limiter or shield protecting the wall from major damage. Thermal gradients that occur during the interaction can produce currents whose associated magnetic field also helps shield the wall

Major health problems and their economic impact on beef cattle under two different feedlot systems in Brazil

Directory of Open Access Journals (Sweden)

Pedro Malafaia

Full Text Available Abstract: This study aimed to describe the diagnosis of health problems and to evaluate the cost of their treatment for cattle raised in feedlots to be slaughtered or to be sold as sires for cow-calf systems. Bovine respiratory disease and digestive disorders were the main problems diagnosed in the feedlot for slaughter; the cost for treatment was high, accounting for 9.7 to 20.9 kg of live weight (LW or the equivalent of 7 to 15% of total LW gained over the days on feed. Due to the high intake of starch-rich concentrate, rumen and fecal pH was lower, whilst rumen osmolarity and blood lactate were higher in cattle fed for slaughter. Cattle affected by digestive disorders spent on average four additional days in the feedlot. Diseases and cost of treatments were associated with lower average daily gain and considerable economic losses. Health problems commonly observed in the feedlots for slaughter were not observed in the feedlots for males to be sold as sires. The most likely reason for this observation was the more careful nutrition and prophylactic health management in sire production systems, which produce animals of much higher selling price. Results from this study suggest that health problems found in feedlots for slaughter may not only reduce animal productivity and profitability, but also the welfare of the animals. The systemic understaffing of livestock cattle workers and veterinarians in large feedlots in Brazil results in under reporting of diseases and lack to understand epidemiological context and disease prevention.

Health protection guidelines for electromagnetic field exposures

International Nuclear Information System (INIS)

Taki, Masao

1999-01-01

In order to protect human health from excessive exposure to electromagnetic fields safety guidelines have been established by national and international organizations. The International Commission on Nonionization Radiation Protection is one of these organizations, whose guidelines are briefly regarded as typical. The activities on this issue in various countries are reviewed. Recent situations and the problems still unsolved are also discussed. (author)

RELATIVISTIC HEAVY ION PHYSICS: A THEORETICAL OVERVIEW.

Energy Technology Data Exchange (ETDEWEB)

KHARZEEV,D.

2004-03-28

This is a mini-review of recent theoretical work in the field of relativistic heavy ion physics. The following topics are discussed initial conditions and the Color Glass Condensate; approach to thermalization and the hydrodynamic evolution; hard probes and the properties of the Quark-Gluon Plasma. Some of the unsolved problems and potentially promising directions for future research are listed as well.

Biogas production from slaughterhouse wastes

Energy Technology Data Exchange (ETDEWEB)

Schmillen, K.; Spessert, B.

1983-08-01

Anaerobic digestion of slaughterhouse wastes can remove wastes and keep them out of the sewage. Furthermore it produces energy of high value. Therefore it is a benefit to public health, pollution control, the economy and management. Today some unsolved problems still impede the introduction of this new technology, thus requiring the construction of a prototype system as soon as possible.

Therapeutic Strategies and Intellectualism in On Anger by Seneca

Directory of Open Access Journals (Sweden)

Rodrigo Sebastián Braicovich

2015-08-01

Full Text Available I try to show that a the treatise On Anger by Seneca includes not one but two therapeutic strategies designed to avoid anger and that b the second of these strategies –which has been neglected in the secondary literature– presents unsolvable problems when we contrast it with the Stoic theory of action, which is rooted in intellectualist premises.

Collision and interaction phenomena - a historical outline

International Nuclear Information System (INIS)

Radmaneche, R.

1977-09-01

Collisions and interactions have become important for the description of matter. The author presents an outline which deals with elastic and inelastic collisions, with strong interactions, electromagnetic interactions, weak interactions and gravitational interactions. It is shown that the description of such processes has developed parallel with the understanding of matter and with the mechanism of the phenomena. Current and unsolved problems are mentioned

Applications for fueling of Forsmark-3 and Oskarshamn III

International Nuclear Information System (INIS)

1984-01-01

The method for handling and final disposal of spent nuclear fuel outlined in the report KBS-3 has been found acceptable in relation to conventional and radiation safety. The main institutions agree on this, IAEA and other international institutions deem the method over-safe. The KBS-3 study has left some problems unsolved. Further research projects have been identified. (Aa)

Problem drinking - detection and assessment in general practice.

Science.gov (United States)

Demirkol, Apo; Haber, Paul; Conigrave, Katherine

2011-08-01

Alcohol has long been an integral part of the social life of many Australians. However, alcohol is associated with significant harm to drinkers, and also to nondrinkers. This article explores the role of the general practitioner in the detection and assessment of problem drinking. Excessive alcohol use is a major public health problem and the majority of people who drink excessively go undetected. General practitioners are in a good position to detect excessive alcohol consumption; earlier intervention can help improve outcomes. AUDIT-C is an effective screening tool for the detection of problem drinking. National Health and Medical Research Council guidelines suggest that no more than two standard drinks on each occasion will keep lifetime risk of death from alcohol related disease or injury at a low level. Once an alcohol problem is detected it is important to assess for alcohol dependence, other substance use, motivation to change, psychiatric comorbidities and examination and investigation findings that may be associated with excessive alcohol use. A comprehensive assessment of the impact and risk of harm of the patient's drinking to themselves and others is vital, and may require several consultations.

Deciding on Science: An Analysis of Higher Education Science Student Major Choice Criteria

Science.gov (United States)

White, Stephen Wilson

The number of college students choosing to major in science, technology, engineering, and math (STEM) in the United States affects the size and quality of the American workforce (Winters, 2009). The number of graduates in these academic fields has been on the decline in the United States since the 1960s, which, according to Lips and McNeil (2009), has resulted in a diminished ability of the United States to compete in science and engineering on the world stage. The purpose of this research was to learn why students chose a STEM major and determine what decision criteria influenced this decision. According to Ajzen's (1991) theory of planned behavior (TPB), the key components of decision-making can be quantified and used as predictors of behavior. In this study the STEM majors' decision criteria were compared between different institution types (two-year, public four-year, and private four-year), and between demographic groups (age and sex). Career, grade, intrinsic, self-efficacy, and self-determination were reported as motivational factors by a majority of science majors participating in this study. Few students reported being influenced by friends and family when deciding to major in science. Science students overwhelmingly attributed the desire to solve meaningful problems as central to their decision to major in science. A majority of students surveyed credited a teacher for influencing their desire to pursue science as a college major. This new information about the motivational construct of the studied group of science majors can be applied to the previously stated problem of not enough STEM majors in the American higher education system to provide workers required to fill the demand of a globally STEM-competitive United States (National Academy of Sciences, National Academy of Engineering, & Institute of Medicine, 2010).

Authentication: A Standard Problem or a Problem of Standards?

Directory of Open Access Journals (Sweden)

Amanda Capes-Davis

2016-06-01

Full Text Available Reproducibility and transparency in biomedical sciences have been called into question, and scientists have been found wanting as a result. Putting aside deliberate fraud, there is evidence that a major contributor to lack of reproducibility is insufficient quality assurance of reagents used in preclinical research. Cell lines are widely used in biomedical research to understand fundamental biological processes and disease states, yet most researchers do not perform a simple, affordable test to authenticate these key resources. Here, we provide a synopsis of the problems we face and how standards can contribute to an achievable solution.

Some Major Issues Influencing Nuclear Energy Prospective

International Nuclear Information System (INIS)

Feretic, D.

2012-01-01

The presentation analyses some issues which are of particular importance for future nuclear power application. These include duration of uranium reserves and high level radioactive waste decay period in function of uranium reserves (determined, assumed and speculative) and type of fuel cycle used. Public acceptance during essential historical milestones of nuclear power use, influence of safety and compatibility evaluations, quantified risk, externalities and nuclear accidents. Short review of major accidents, causes, consequences, impact of LNT and hormesis hypothesis. Particular problem for future of nuclear power is potential shortage of experienced personnel due to long period without plants construction. To address some of problems which may face future investors a brief review of specific events experienced during construction of NPP Krsko is presented. Such events could be of interest to countries planning to construct nuclear power plant.(author).

GAMING LAW ENFORCEMENT AND CRIMINAL JUSTICE PROBLEMS,

Science.gov (United States)

and techniques of gaming as they apply to the study of law enforcement problems in general, and to show how gaming may assist in identifying and overcoming some of the major pitfalls in law enforcement planning. (Author)

Teenage Pregnancy: A contemporary problem of adolescence

Directory of Open Access Journals (Sweden)

Lynette Acres

1985-09-01

Full Text Available Teenage pregnancy, particularly pregnancy in school-aged girls below the age of 17 years, is a major community health problem. The incidence of such pregnancies is increasing to what some believe are epidemic proportions.

Congenital Rubella Syndrome - A Major Review and Update

Directory of Open Access Journals (Sweden)

Nure Ishrat Nazme

2015-07-01

Full Text Available Rubella is a major public health problem which is usually a mild rash illness in children and adults. However, it has devastating systemic consequences when rubella virus crosses the placental barrier and infects fetal tissue resulting in congenital rubella syndrome (CRS. Congenital rubella syndrome is an under-recognized public health problem in Bangladesh and the burden of the disease weighs heavily on patients and society; therefore, routine vaccination and other preventative strategies are strongly encouraged. Extensive surveillance studies should be conducted to eliminate CRS from our country. In this review, we will characterize the epidemiology of CRS; describe the patho-phyisiology, clinical features and laboratory testing for the disease, and discuss measures needed for prevention of rubella and CRS.

Nonlinear dynamics of quadratically cubic systems

International Nuclear Information System (INIS)

Rudenko, O V

2013-01-01

We propose a modified form of the well-known nonlinear dynamic equations with quadratic relations used to model a cubic nonlinearity. We show that such quadratically cubic equations sometimes allow exact solutions and sometimes make the original problem easier to analyze qualitatively. Occasionally, exact solutions provide a useful tool for studying new phenomena. Examples considered include nonlinear ordinary differential equations and Hopf, Burgers, Korteweg–de Vries, and nonlinear Schrödinger partial differential equations. Some problems are solved exactly in the space–time and spectral representations. Unsolved problems potentially solvable by the proposed approach are listed. (methodological notes)

Scientific and technical problems in the production of coke

Energy Technology Data Exchange (ETDEWEB)

Glushchenko, I M

1979-05-01

This paper lists several scientific and technological problems facing the producers of coke in the future. The demand for coke on the world market is steadily increasing despite the efforts of metallurgists to find non-coke methods of ore smelting. The major problems are held to be the gap between very successful results of research and the lack of their application to industry, unsatisfactory coke oven construction, problems in quenching and imperfections in the formed coke process. (In Russian)

Agricultural problems

International Nuclear Information System (INIS)

Bickerton, George E.

1997-01-01

Although there were not reasons to deplore against major activity release from any of the 110 industrial reactors authorized to operate in US, the nuclear incident that occurred at the Three Mile Island Plant in 1979 urged the public conscience toward the necessity of readiness to cope with events of this type. The personnel of the Emergency Planning Office functioning in the frame of US Department of Agriculture has already participated in around 600 intervention drillings on a federal, local or state scale to plan, test or asses radiological emergency plans or to intervene locally. These exercises allowed acquiring a significant experience in elaborating emergency plans, planning the drillings, working out scenarios and evaluation of the potential impact of accidents from the agricultural point of view. We have also taken part in different international drillings among which the most recent are INEX 1 and RADEX 94. We have found on these occasions that the agricultural problems are essential preoccupations in most of the cases no matter if the context is international, national, local or of state level. The paper poses problems specifically related to milk, fruits and vegetables, soils, meat and meat products. Finally the paper discusses issues like drilling planning, alarm and notification, sampling strategy, access authorizations for farmers, removing of contamination wastes. A number of social, political and economical relating problems are also mentioned

Clarification process: Resolution of decision-problem conditions

Science.gov (United States)

Dieterly, D. L.

1980-01-01

A model of a general process which occurs in both decisionmaking and problem-solving tasks is presented. It is called the clarification model and is highly dependent on information flow. The model addresses the possible constraints of individual indifferences and experience in achieving success in resolving decision-problem conditions. As indicated, the application of the clarification process model is only necessary for certain classes of the basic decision-problem condition. With less complex decision problem conditions, certain phases of the model may be omitted. The model may be applied across a wide range of decision problem conditions. The model consists of two major components: (1) the five-phase prescriptive sequence (based on previous approaches to both concepts) and (2) the information manipulation function (which draws upon current ideas in the areas of information processing, computer programming, memory, and thinking). The two components are linked together to provide a structure that assists in understanding the process of resolving problems and making decisions.

General versus gender-specific attributes of the psychology major.

Science.gov (United States)

McCray, Jason A; King, Alan R; Bailly, Matthew D

2005-04-01

In the present study, the authors extended the search for general and gender-specific factors associated with the selection of psychology as a college major by using the Family Environment Scale (FES; R. H. Moos & B. S. Moos, 1994) and Coolidge Axis II Inventory (CATI; F. L. Coolidge & M. M. Merwin, 1992). The findings were restricted to one general (Schizoid) and one gender-specific (Self-Defeating) set of personality traits that seemed to be associated with the selection of a college major. The intuitive role of many presumed gender-specific factors (e.g., women are more open to discussing personal problems with others) may prove difficult to establish empirically.

A road safety information system : from concept to implementation. Contribution to the Road Safety Training Course of the World Bank, 1 May 2001, Washington, D.C.

OpenAIRE

Wegman, F.C.M.

2001-01-01

It is a proven fact that road safety problems are not unsolvable: what is man-made can also be unmade by man. This leads to questions such as which priorities to set, which measures to take, which effects to expect, what costs are involved, and how these can be financed. In order to be able to answer all these questions, data, knowledge, and information are needed to give a comprehensive and objective picture of the road safety problems and of the effectiveness and efficiency of potential roa...

Confinement and 4-manifolds

CERN Multimedia

CERN. Geneva

2014-01-01

In this talk I will survey a connection between two very challenging problems, one in physics and one in math. The physics problem involves quantitative understanding of confinement in a system with least amount of supersymmetry that has been studied so far and that has a wide range of applications, from semi-realistic string models to qualitatively new examples of gauge-gravity duality. Surprisingly, the rich physics of this system translates into incredibly rich mathematics of the only remaining unsolved case of the Poincare conjecture.

Health problems of street children and women in Awassa, Southern ...

African Journals Online (AJOL)

Background: The number of street children and women in major towns of Ethiopia is rapidly increasing. Yet their problems have not been fully studied. Objective: To assess health and related problems in street children and women. Methods: A cross sectional survey was conducted in Awassa town, women southern ...

Police close unsolved 'climategate' investigation

Science.gov (United States)

Lavender, Gemma

2012-09-01

Police in Norfolk in the UK have closed an investigation into the hacking of e-mails at the University of East Anglia's Climate Research Unit (CRU) after admitting that they will not be able to find the hackers who broke into CRU computer servers.

Conceptual problem solving in high school physics

Science.gov (United States)

Docktor, Jennifer L.; Strand, Natalie E.; Mestre, José P.; Ross, Brian H.

2015-12-01

Problem solving is a critical element of learning physics. However, traditional instruction often emphasizes the quantitative aspects of problem solving such as equations and mathematical procedures rather than qualitative analysis for selecting appropriate concepts and principles. This study describes the development and evaluation of an instructional approach called Conceptual Problem Solving (CPS) which guides students to identify principles, justify their use, and plan their solution in writing before solving a problem. The CPS approach was implemented by high school physics teachers at three schools for major theorems and conservation laws in mechanics and CPS-taught classes were compared to control classes taught using traditional problem solving methods. Information about the teachers' implementation of the approach was gathered from classroom observations and interviews, and the effectiveness of the approach was evaluated from a series of written assessments. Results indicated that teachers found CPS easy to integrate into their curricula, students engaged in classroom discussions and produced problem solutions of a higher quality than before, and students scored higher on conceptual and problem solving measures.

Conceptual problem solving in high school physics

Directory of Open Access Journals (Sweden)

Jennifer L. Docktor

2015-09-01

Full Text Available Problem solving is a critical element of learning physics. However, traditional instruction often emphasizes the quantitative aspects of problem solving such as equations and mathematical procedures rather than qualitative analysis for selecting appropriate concepts and principles. This study describes the development and evaluation of an instructional approach called Conceptual Problem Solving (CPS which guides students to identify principles, justify their use, and plan their solution in writing before solving a problem. The CPS approach was implemented by high school physics teachers at three schools for major theorems and conservation laws in mechanics and CPS-taught classes were compared to control classes taught using traditional problem solving methods. Information about the teachers’ implementation of the approach was gathered from classroom observations and interviews, and the effectiveness of the approach was evaluated from a series of written assessments. Results indicated that teachers found CPS easy to integrate into their curricula, students engaged in classroom discussions and produced problem solutions of a higher quality than before, and students scored higher on conceptual and problem solving measures.

Vocational Education in Tourism: Conceptual Framework Problems

Directory of Open Access Journals (Sweden)

Galina Shchuka

2012-12-01

Full Text Available This article analyzes the basic concepts that define the essence of the system of vocational education and helps to analyze the problem of tourism staffing support. According to authors’ hypothesis, the personnel problem is related to the imperfection of the tourism conceptual framework. As of all enterprises of travel industry only travel agencies and accommodation facilities work with tourists, the author proves that personnel training for these businesses is the major objective of vocational training in tourism.

Low pollution combustor designs for CTOL engines - Results of the Experimental Clean Combustor Program

Science.gov (United States)

Roberts, R.; Peduzzi, A.; Niedzwiecki, R. W.

1976-01-01

The NASA/Pratt & Whitney Aircraft Experimental Clean Combustor Program is a multi-year, major contract effort. Primary program objectives are the generation of combustor technology for development of advanced commercial CTOL engines with lower exhaust emissions than current aircraft and demonstration of this technology in a full-scale JT9D engine in 1976. This paper describes the pollution and performance goals, Phase I and II test results, and the Phase III combustor hardware, pollution sampling techniques, and test plans. Best results were obtained with the Vorbix concept which employs multiple burning zones and improved fuel preparation and distribution. Substantial reductions were achieved in all pollutant categories, meeting the 1979 EPA standards for NOx, THC, and smoke when extrapolated to JT9D cycle conditions. The Vorbix concept additionally demonstrated the capability for acceptable altitude relight and did not appear to have unsolvable durability or exit temperature distribution problems.

Sales plan generation problem on TV broadcasting

Directory of Open Access Journals (Sweden)

Özlem Cosgun

2016-07-01

Full Text Available Major advertisers and/or advertisement agencies purchase hundreds of slots during a given broadcast period. Deterministic optimization approaches have been well developed for the problem of meeting client requests. The challenging task for the academic research currently is to address optimization problem under uncertainty. This paper is concerned with the sales plan generation problem when the audience levels of advertisement slots are random variables with known probability distributions. There are several constraints the TV networks must meet including client budget, product category and demographic information, plan weighting by week, program mix requirements, and the lengths of advertisement slots desired by the client. We formulate the problem as a chance constrained goal program and we demonstrate that it provides a robust solution with a user specified level of reliability.

Problems and Counselling Needs of Corps Members in Nigeria (Pp ...

African Journals Online (AJOL)

Nekky Umera

1973-05-22

May 22, 1973 ... major problems and counseling needs of Corps Members were psychological in nature. ... and must be resolved sufficiently at a given stage if the individual is to cope successfully with ... (ii) Is there any difference between the problems of male and female ... youth corps member of different age group?

Assessing the Personal Financial Problems of Junior Enlisted Personnel

National Research Council Canada - National Science Library

Buddin, Richard

2002-01-01

.... Surveys of military personnel show that, particularly for junior personnel, financial problems constitute a major source of stress, subordinate only to increased workload and family separation...

Suicide Risk, Aggression and Violence in Major Psychiatric Disorders

Directory of Open Access Journals (Sweden)

G Mousavi

2004-02-01

Full Text Available Background: Aggression, violence and Suicide are important problems of mental health in our society. They almost always cause disability, death, or other social problems. Appropriate measures can be taken if the distribution of behaviors and suicide risk are well studied in various psychiatric disorders. Methods: This was a cross-sectional study. We studied 801 psychiatric patients who were admitted in a psychiatric emergency unit in Isfahan, Iran, for aggression, violence and risk of suicide. Information was obtained from a 30-item questionnaire, filled by the same physician. Results: About one-third of patients had aggression and/or violence on admission or during hours before it. It was most prevalent in men of 12-26 years old and in bipolar mood disorder patients. "High suicide risk" was markedly found in patients with major depressive disorder. Differences of these phenomena were statistically Conclusion: Our findings show a higher rate of aggression and violence in emergency psychiatric patients than in studies done in other countries. It may be due to higher prevalence of bipolar patients in the study field. The finding of "High suicidal risk" in major depression patients warrent systematic preventive programs. Keywords: Suicide risk, Aggression, Violence

Science-Technology-Society literacy in college non-majors biology: Comparing problem/case studies based learning and traditional expository methods of instruction

Science.gov (United States)

Peters, John S.

This study used a multiple response model (MRM) on selected items from the Views on Science-Technology-Society (VOSTS) survey to examine science-technology-society (STS) literacy among college non-science majors' taught using Problem/Case Studies Based Learning (PBL/CSBL) and traditional expository methods of instruction. An initial pilot investigation of 15 VOSTS items produced a valid and reliable scoring model which can be used to quantitatively assess student literacy on a variety of STS topics deemed important for informed civic engagement in science related social and environmental issues. The new scoring model allows for the use of parametric inferential statistics to test hypotheses about factors influencing STS literacy. The follow-up cross-institutional study comparing teaching methods employed Hierarchical Linear Modeling (HLM) to model the efficiency and equitability of instructional methods on STS literacy. A cluster analysis was also used to compare pre and post course patterns of student views on the set of positions expressed within VOSTS items. HLM analysis revealed significantly higher instructional efficiency in the PBL/CSBL study group for 4 of the 35 STS attitude indices (characterization of media vs. school science; tentativeness of scientific models; cultural influences on scientific research), and more equitable effects of traditional instruction on one attitude index (interdependence of science and technology). Cluster analysis revealed generally stable patterns of pre to post course views across study groups, but also revealed possible teaching method effects on the relationship between the views expressed within VOSTS items with respect to (1) interdependency of science and technology; (2) anti-technology; (3) socioscientific decision-making; (4) scientific/technological solutions to environmental problems; (5) usefulness of school vs. media characterizations of science; (6) social constructivist vs. objectivist views of theories; (7

Interpersonal problems across levels of the psychopathology hierarchy.

Science.gov (United States)

Girard, Jeffrey M; Wright, Aidan G C; Beeney, Joseph E; Lazarus, Sophie A; Scott, Lori N; Stepp, Stephanie D; Pilkonis, Paul A

2017-11-01

We examined the relationship between psychopathology and interpersonal problems in a sample of 825 clinical and community participants. Sixteen psychiatric diagnoses and five transdiagnostic dimensions were examined in relation to self-reported interpersonal problems. The structural summary method was used with the Inventory of Interpersonal Problems Circumplex Scales to examine interpersonal problem profiles for each diagnosis and dimension. We built a structural model of mental disorders including factors corresponding to detachment (avoidant personality, social phobia, major depression), internalizing (dependent personality, borderline personality, panic disorder, posttraumatic stress, major depression), disinhibition (antisocial personality, drug dependence, alcohol dependence, borderline personality), dominance (histrionic personality, narcissistic personality, paranoid personality), and compulsivity (obsessive-compulsive personality). All dimensions showed good interpersonal prototypicality (e.g., detachment was defined by a socially avoidant/nonassertive interpersonal profile) except for internalizing, which was diffusely associated with elevated interpersonal distress. The findings for individual disorders were largely consistent with the dimension that each disorder loaded on, with the exception of the internalizing and dominance disorders, which were interpersonally heterogeneous. These results replicate previous findings and provide novel insights into social dysfunction in psychopathology by wedding the power of hierarchical (i.e., dimensional) modeling and interpersonal circumplex assessment. Copyright © 2017 Elsevier Inc. All rights reserved.

Community mobilization and the framing of alcohol-related problems.

Science.gov (United States)

Herd, Denise

2010-03-01

The goal of this study was to describe how activists engaged in campaigns to change alcohol policies in inner city areas framed alcohol problems, and whether or not their frameworks reflected major models used in the field, such as the alcoholism as a disease model, an alcohol problems perspective, or a public health approach to alcohol problems. The findings showed that activists' models shared some aspects with dominant approaches which tend to focus on individuals and to a lesser extent on regulating alcohol marketing and sales. However, activists' models differed in significant ways by focusing on community level problems with alcohol; on problems with social norms regarding alcohol use; and on the relationship of alcohol use to illicit drugs.

Unilateral contact problems variational methods and existence theorems

CERN Document Server

Eck, Christof; Krbec, Miroslav

2005-01-01

The mathematical analysis of contact problems, with or without friction, is an area where progress depends heavily on the integration of pure and applied mathematics. This book presents the state of the art in the mathematical analysis of unilateral contact problems with friction, along with a major part of the analysis of dynamic contact problems without friction. Much of this monograph emerged from the authors'' research activities over the past 10 years and deals with an approach proven fruitful in many situations. Starting from thin estimates of possible solutions, this approach is based on an approximation of the problem and the proof of a moderate partial regularity of the solution to the approximate problem. This in turn makes use of the shift (or translation) technique - an important yet often overlooked tool for contact problems and other nonlinear problems with limited regularity. The authors pay careful attention to quantification and precise results to get optimal bounds in sufficient conditions f...

Closed nuclear facilities in Estonia: developments and problems

International Nuclear Information System (INIS)

Realo, E.; Realo, K.

2000-01-01

At present Estonia has no operating nuclear or a radioactive material production facility. As a legacy of the past the country has become responsible for the decommissioning of two large nuclear cycle facilities of the former USSR. Besides limited funding, major problems arise from deficiencies in legislation, expertise, training and research. International co-operation has been of immense importance to overcome the problems, to establish the national radiation protection and radioactive waste management infrastructure and to launch decommissioning and remediation activities. An overview is given on the status and problems. Copyright (2000) Australasian Radiation Protection Society Inc

Methodological pitfalls in early detection studies–the NAPE Lecture 2002

DEFF Research Database (Denmark)

Svein, Friis; Tor Ketil, Larsen; Melle, Ingrid

2003-01-01

Identifies and discusses methodological pitfalls that may help explain why many questions around early detection (ED) and duration of untreated psychosis (DUP) are still unsolved. This paper concentrates on pitfalls in sampling, measurement, and data analyses. The main problems seem to be: (1) Sa...... to identify the pitfalls, and to estimate and discuss their influence. (PsycINFO Database Record (c) 2016 APA, all rights reserved)...

Problem solving performance and learning strategies of undergraduate students who solved microbiology problems using IMMEX educational software

Science.gov (United States)

Ebomoyi, Josephine Itota

The objectives of this study were as follows: (1) Determine the relationship between learning strategies and performance in problem solving, (2) Explore the role of a student's declared major on performance in problem solving, (3) Understand the decision making process of high and low achievers during problem solving. Participants (N = 65) solved problems using the Interactive multimedia exercise (IMMEX) software. All participants not only solved "Microquest," which focuses on cellular processes and mode of action of antibiotics, but also "Creeping Crud," which focuses on the cause, origin and transmission of diseases. Participants also responded to the "Motivated Strategy Learning Questionnaire" (MSLQ). Hierarchical multiple regression was used for analysis with GPA (Gracie point average) as a control. There were 49 (78.6%) that successfully solved "Microquest" while 52 (82.5%) successfully solved "Creeping Crud". Metacognitive self regulation strategy was significantly (p low achievers. Common strategies and attributes included metacognitive skills, writing to keep track, using prior knowledge. Others included elements of frustration/confusion and self-esteem problems. The implications for educational and relevance to real life situations are discussed.

Supply network configuration—A benchmarking problem

Science.gov (United States)

Brandenburg, Marcus

2018-03-01

Managing supply networks is a highly relevant task that strongly influences the competitiveness of firms from various industries. Designing supply networks is a strategic process that considerably affects the structure of the whole network. In contrast, supply networks for new products are configured without major adaptations of the existing structure, but the network has to be configured before the new product is actually launched in the marketplace. Due to dynamics and uncertainties, the resulting planning problem is highly complex. However, formal models and solution approaches that support supply network configuration decisions for new products are scant. The paper at hand aims at stimulating related model-based research. To formulate mathematical models and solution procedures, a benchmarking problem is introduced which is derived from a case study of a cosmetics manufacturer. Tasks, objectives, and constraints of the problem are described in great detail and numerical values and ranges of all problem parameters are given. In addition, several directions for future research are suggested.

Challenges of Environmental Problems to the Philosophy of Education

Science.gov (United States)

Kato, Moricmichi

2015-01-01

We live in an age in which the destruction of the environment has become a major concern. However, until recently, environmental problems have not become a major issue for the philosophy of education. The reason for this is that for a very long time the philosophy of education was intimately related to the concept of nature as the foundation and…

Psychosocial and Mental Health Problems of Older People in Postearthquake Nepal.

Science.gov (United States)

Adhikari, Ramesh P; Upadhaya, Nawaraj; Paudel, Sasmita; Pokhrel, Ruja; Bhandari, Nagendra; Cole, Laura; Koirala, Suraj

2017-03-01

To identify community perceptions on psychosocial and mental health problems of older people in postearthquake situation in Nepal. A qualitative methodology was adopted to explore the experience and opinions of older people, social workers, school teachers, health workers, and nongovernmental organization workers on the psychosocial and mental health problems of older people in Nepal, using key informant interviews. Major local vocabulary for older peoples' psychosocial and mental health problems were "bichalan" (variation in mood and feeling), "ekohoro" (becoming single minded), "athmabiswasko kami" (low self-esteem), and "bina karan rune" (crying without any reason). The major causes attributed to older people's problems were physical injury, disability, family conflict, and economic problems. Forgetfulness, tiredness, loss of concentration, restlessness, and isolation were observed in older people since the 2015 earthquake. The findings suggest that earthquake had negative impact on older people's psychosocial well-being; however, little support or treatment options have been made available to these individuals. The tailor-made community-based psychosocial and mental health programs for older people are needed.

Enhancing the Accounting Major with Online Learning

Directory of Open Access Journals (Sweden)

Hershey Friedman Ph.D

2013-07-01

Full Text Available Accounting majors who wish to be successful in life must learn to acquire knowledge using all kinds of platforms. The belief that the only way people can learn is by classroom instruction is not supported by research. The authors show how online learning is an important tool for achieving the various goals of accounting education that should include creativity, collaboration, communication, critical thinking and problem solving. The authors conclude that the optimal method to teach accounting is by combining face-to-face learning with on-line learning.

Major Environmental Policy in 2000

Energy Technology Data Exchange (ETDEWEB)

Choi, Hong Jin [Ministry Of Environment, Kwachon (Korea)

2000-04-01

As a new millennium has started, there are active movements developing a basic paradigm of vision and policy over a nation-wide to prepare changes actively. For the environmental sector, it is possible to live in a pleasant environment if everyone prepare and work together like dealing with Y2K problem. With a goal of being an environmentally advanced country in the early new millennium, it is planned to improve a basic life environment such as water and air and to promote an advanced environmental management policy for showing results of its reform in 2000. Therefore, it examines environmental management circumstances and a direction of environmental policy first and it discusses more about major environmental policy related to petroleum industry. 7 tabs.

Risk Factors in Adolescent Problem Behaviors Among Native and Nonnative Americans

OpenAIRE

Christensen, Roger B.

1998-01-01

The high incidence of adolescent problem behaviors in the United States raises major concerns. These problem behaviors include: sexually transmitted diseases, unintended pregnancies, suicide, depression, substance abuse, crime against persons and property, and delinquency. Consequently, there continues to be a high level of concern and interest in different ethnic populations of adolescents and their level of risk. This study evaluated the following problem behaviors: substance abuse, suic...

Students Use Graphic Organizers to Improve Mathematical Problem-Solving Communications

Science.gov (United States)

Zollman, Alan

2009-01-01

Improving students' problem-solving abilities is a major, if not the major, goal of middle grades mathematics. To address this goal, the author, who is a university mathematics educator, and nine inner-city middle school teachers developed a math/science action research project. This article describes their unique approach to mathematical problem…

Major heat exchanger performance in Ontario Hydro-operated CANDU nuclear generating stations

International Nuclear Information System (INIS)

Dueck, D.G.

1980-01-01

The performance of heat exchangers is described in terms of their impact on the unit in the form of forced outages and deratings as well as incapability due to scheduled outages. Some major problems with heat exchangers are highlighted. (auth)

Total parenteral nutrition - Problems in compatibility and stability

DEFF Research Database (Denmark)

Schroder, A.M.

2008-01-01

Adding calcium, trace elements and vitamins could turn parenteral nutrition into a dangerous product, which could harm the patient. This article focuses on the major pharmaceutical problems of parenteral. nutrition when adding nutritional compounds Udgivelsesdato: 2008...

Evolving Neural Turing Machines for Reward-based Learning

DEFF Research Database (Denmark)

Greve, Rasmus Boll; Jacobsen, Emil Juul; Risi, Sebastian

2016-01-01

An unsolved problem in neuroevolution (NE) is to evolve artificial neural networks (ANN) that can store and use information to change their behavior online. While plastic neural networks have shown promise in this context, they have difficulties retaining information over longer periods of time...... version of the double T-Maze, a complex reinforcement-like learning problem. In the T-Maze learning task the agent uses the memory bank to display adaptive behavior that normally requires a plastic ANN, thereby suggesting a complementary and effective mechanism for adaptive behavior in NE....

[Consequences learned from the use of chemical weapons during the First World War for the modern military medicine].

Science.gov (United States)

Belskikh, A N; Basharin, V A; Chepur, S V; Khalimov, Yu Sh; Markizova, N F

2015-08-01

The article describes the way medical service dealed with problems resulted from the use of chemical weapons during the First World War (1914-1918). It was revealed that many of the abovementioned problems remain unsolved up to the present moment. It is stated the existence of the threat of use of chemical weapons in modem military conflicts, which expands the area of responsibility for medical chemical protection. The authors proved necessity and algorithm of the training system, considered as a part of medical protection in case of adverse factors of chemical nature.

Supersymmetry breaking with extra dimensions

International Nuclear Information System (INIS)

Zwirner, Fabio

2004-01-01

This talk reviews some aspects of supersymmetry breaking in the presence of extra dimensions. The first part is a general introduction, recalling the motivations for supersymmetry and extra dimensions, as well as some unsolved problems of four-dimensional models of supersymmetry breaking. The central part is a more focused introduction to a mechanism for (super)symmetry breaking, proposed first by Scherk and Schwarz, where extra dimensions play a crucial role. The last part is devoted to the description of some recent results and of some open problems. (author)

ENERGY GAIN BY MEANS OF RESONANCE IN THE TESLA COIL

Directory of Open Access Journals (Sweden)

Yu. Batygin

2016-12-01

Full Text Available An analytical review of publications on the problem, first formulated by Nikola Tesla, generating «free» energy from the air in the surrounding space has been presented. The hypothesis of the resonance phenomenon as a «key» to the air energy has been advanced. The main unsolved problem is the extrac-tion of «free» energy (proposed to call it «resonance» and its supply to the electrical load have been noted. It is expected that the quality factor of the secondary circuit must be large enough.

Material-Point Analysis of Large-Strain Problems

DEFF Research Database (Denmark)

Andersen, Søren

The aim of this thesis is to apply and improve the material-point method for modelling of geotechnical problems. One of the geotechnical phenomena that is a subject of active research is the study of landslides. A large amount of research is focused on determining when slopes become unstable. Hence......, it is possible to predict if a certain slope is stable using commercial finite element or finite difference software such as PLAXIS, ABAQUS or FLAC. However, the dynamics during a landslide are less explored. The material-point method (MPM) is a novel numerical method aimed at analysing problems involving...... materials subjected to large strains in a dynamical time–space domain. This thesis explores the material-point method with the specific aim of improving the performance for geotechnical problems. Large-strain geotechnical problems such as landslides pose a major challenge to model numerically. Employing...

Identification of technical problems encountered in the shallow land burial of low-level radioactive wastes

International Nuclear Information System (INIS)

Jacobs, D.G.; Epler, J.S.; Rose, R.R.

1980-03-01

A review of problems encountered in the shallow land burial of low-level radioactive wastes has been made in support of the technical aspects of the National Low-Level Waste (LLW) Management Research and Development Program being administered by the Low-Level Waste Management Program Office, Oak Ridge National Laboratory. The operating histories of burial sites at six major DOE and five commercial facilities in the US have been examined and several major problems identified. The problems experienced st the sites have been grouped into general categories dealing with site development, waste characterization, operation, and performance evaluation. Based on this grouping of the problem, a number of major technical issues have been identified which should be incorporated into program plans for further research and development. For each technical issue a discussion is presented relating the issue to a particular problem, identifying some recent or current related research, and suggesting further work necessary for resolving the issue. Major technical issues which have been identified include the need for improved water management, further understanding of the effect of chemical and physical parameters on radionuclide migration, more comprehensive waste records, improved programs for performance monitoring and evaluation, development of better predictive capabilities, evaluation of space utilization, and improved management control

Identification of technical problems encountered in the shallow land burial of low-level radioactive wastes

Energy Technology Data Exchange (ETDEWEB)

Jacobs, D.G.; Epler, J.S.; Rose, R.R.

1980-03-01

A review of problems encountered in the shallow land burial of low-level radioactive wastes has been made in support of the technical aspects of the National Low-Level Waste (LLW) Management Research and Development Program being administered by the Low-Level Waste Management Program Office, Oak Ridge National Laboratory. The operating histories of burial sites at six major DOE and five commercial facilities in the US have been examined and several major problems identified. The problems experienced st the sites have been grouped into general categories dealing with site development, waste characterization, operation, and performance evaluation. Based on this grouping of the problem, a number of major technical issues have been identified which should be incorporated into program plans for further research and development. For each technical issue a discussion is presented relating the issue to a particular problem, identifying some recent or current related research, and suggesting further work necessary for resolving the issue. Major technical issues which have been identified include the need for improved water management, further understanding of the effect of chemical and physical parameters on radionuclide migration, more comprehensive waste records, improved programs for performance monitoring and evaluation, development of better predictive capabilities, evaluation of space utilization, and improved management control.

CHASM Challenge Problem: Lagrangian Hydrodynamics

Energy Technology Data Exchange (ETDEWEB)

Hornung, R [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Keasler, J [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gokhale, M [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2010-09-10

Computer simulations of many science and engineering problems require modeling the equations of hydrodynamics which describe the motion of materials relative to each other induced by various forces. Many important DoD simulation problems involve complex multi-material systems that undergo large deformations. Examples include the analysis of armor defense, penetration mechanics, blast effects, structural integrity, and conventional munitions such as shaped charges and explosively formed projectiles. Indeed, the original motivation for developing codes that solve the equations of hydrodynamics, herein referred to as “hydrocodes”, was to solve problems with defense applications. The FY2010 Requirements Analysis Report issued by the DoD High Performance Computing Modernization Program (HPCMP) Office shows that a major portion of DoD HPC activities involves hydrocodes [HPCMP2010]. The report surveyed 496 projects across the Services and various Agencies, representing 4,050 HPCMP users at more than 125 locations, including government, contractors, and academia, and grouped each project into one of ten categories.

Do Biology Majors Really Differ from Non–STEM Majors?

Science.gov (United States)

Cotner, Sehoya; Thompson, Seth; Wright, Robin

2017-01-01

Recent calls to action urge sweeping reform in science education, advocating for improved learning for all students—including those majoring in fields beyond the sciences. However, little work has been done to characterize the differences—if any exist—between students planning a career in science and those studying other disciplines. We describe an attempt to clarify, in broad terms, how non–STEM (science, technology, engineering, and mathematics) majors differ from life sciences majors, and how they are similar. Using survey responses and institutional data, we find that non–STEM majors are not unilaterally science averse; non–STEM majors are more likely than biology majors to hold misconceptions about the nature of science, yet they are not completely ignorant of how science works; non–STEM majors are less likely than biology majors to see science as personally relevant; and non–STEM majors populations are likely to be more diverse—with respect to incoming knowledge, perceptions, backgrounds, and skills—than a biology majors population. We encourage science educators to consider these characteristics when designing curricula for future scientists or simply for a well-informed citizenry. PMID:28798210

Competency test for selecting majors to produce competitive vocational graduates in industry

Directory of Open Access Journals (Sweden)

Jiwa Permana Agus Aan

2018-01-01

Full Text Available President of Indonesia, Jokowi reoriented vocational school graduate toward demand driven graduates that is graduates who have certificate and skill required by industry. The initial stage of the new student on vocational school is choosing a major. At first step, students often confuse in choosing the majors they want. The mistake of choosing a department will be a set beck to the motivation of learning and skill, later will impade students future career. Thus competence test is needed to helping them in choosing the majors according to their competence. The solution to this problem is to conduct online competency tests for new students. The Results of research with 60 responden, 78% corresponds stated that the majors they were in match with their interests. Then the remaining 22% did not match. But the result of the competency assessment of students in match with the majors of is 40% and 60% of students need counseling for selection majors.

Taxonomic Review of Classical and Current Literature on the Perennial American Family Forest Problem

Directory of Open Access Journals (Sweden)

Thomas J. Straka

2011-08-01

Full Text Available One of the fundamental issues in American forest policy has been the small forest ownership problem. Early in the twentieth century, it was called the farm forestry problem, later, the nonindustrial private forest problem, and today, the family forest problem. Family forest owners are thought to manage their lands in a suboptimal manner resulting in low forest productivity relative to other ownership groups. This can lead to future timber supply problems. The exact nature of the problem, especially its social and economic basis, was a common subject of early forestry research studies. This article includes many of the major nonindustrial private forest or family forest studies, from early to current, and classifies them both by themes used by other authors and categories that relate to major research areas in the current literature. A major focus of this literature deals with promoting management on family forest holdings and possible land management incentives and disincentives. Natural trends in family forest ownership, like parcelization, also impact upon forest management opportunities. By developing a taxonomy that classifies these studies by research objective, methodology, owner motivation, and problem definition, this article serves to organize the family forest literature in a manner that provides a temporal framework for better understanding the historical motivation for and development of family forest research in the United States.

Community Mobilization and the Framing of Alcohol-Related Problems

Directory of Open Access Journals (Sweden)

Denise Herd

2010-03-01

Full Text Available The goal of this study was to describe how activists engaged in campaigns to change alcohol policies in inner city areas framed alcohol problems, and whether or not their frameworks reflected major models used in the field, such as the alcoholism as a disease model, an alcohol problems perspective, or a public health approach to alcohol problems. The findings showed that activists’ models shared some aspects with dominant approaches which tend to focus on individuals and to a lesser extent on regulating alcohol marketing and sales. However, activists’ models differed in significant ways by focusing on community level problems with alcohol; on problems with social norms regarding alcohol use; and on the relationship of alcohol use to illicit drugs.

Translating a wicked problem

DEFF Research Database (Denmark)

Tietjen, Anne; Jørgensen, Gertrud

2016-01-01

, place-based and project-oriented process directed at concrete physical outcomes. We frame strategic planning as a translation process where the interaction between human and non-human actors translates a unique, complex and contested situation into an innovated situation. We find that local physical...... on the case of a Danish planning process which was carried out in collaboration with a charitable trust, this paper discusses an emerging strategic planning approach at the municipal level. We use the concept of wicked problems, strategic planning theory and Actor-Network-Theory to study a collaborative...... projects played a major role in this process. First, they acted as a vehicle that assembled planners, politicians and stakeholders to work towards strategic visions across multiple scales. Second and consequently, they stimulated considerable second and third order effects in the form of shared problem...

Problems faced by host nations in accepting visits by nuclear powered merchant ships

International Nuclear Information System (INIS)

Crancher, D.W.

1978-01-01

An international Code of Practice would make a major contribution to the effective regulation of nuclear merchant ships. Ensuring compliance with such a Code would be a significant problem for host nations. An impediment to the development of nuclear shipping is the absence of third party liability provision. There are also problems in host port acceptance into crowded ports and some limitations may be imposed until there is more confidence. There are indications that ship accidents will become the predominant risk and considerably more attention to the problem is required. Waste management need not be a major issue to the acceptance of nuclear merchant ships

The quest for novel modes of excitation in exotic nuclei

Science.gov (United States)

Paar, N.

2010-06-01

This paper provides an insight into several open problems in the quest for novel modes of excitation in nuclei with isospin asymmetry, deformation and finite-temperature characteristics in stellar environments. Major unsolved problems include the nature of pygmy dipole resonances, the quest for various multipole and spin-isospin excitations both in neutron-rich and proton drip-line nuclei mainly driven by loosely bound nucleons, excitations in unstable deformed nuclei and evolution of their properties with the shape phase transition. Exotic modes of excitation in nuclei at finite temperatures characteristic of supernova evolution present open problems with a possible impact in modeling astrophysically relevant weak interaction rates. All these issues challenge self-consistent many-body theory frameworks at the frontiers of on-going research, including nuclear energy density functionals, both phenomenological and constrained by the strong interaction physics of QCD, models based on low-momentum two-nucleon interaction Vlow-k and correlated realistic nucleon-nucleon interaction VUCOM, supplemented by three-body force, as well as two-nucleon and three-nucleon interactions derived from the chiral effective field theory. Joined theoretical and experimental efforts, including research with radioactive isotope beams, are needed to provide insight into dynamical properties of nuclei away from the valley of stability, involving the interplay of isospin asymmetry, deformation and finite temperature.

Cognitive Development, Genetics Problem Solving, and Genetics Instruction: A Critical Review.

Science.gov (United States)

Smith, Mike U.; Sims, O. Suthern, Jr.

1992-01-01

Review of literature concerning problem solving in genetics and Piagetian stage theory. Authors conclude the research suggests that formal-operational thought is not strictly required for the solution of the majority of classical genetics problems; however, some genetic concepts are difficult for concrete operational students to understand.…

Case of two electrostatics problems: Can providing a diagram adversely impact introductory physics students’ problem solving performance?

Directory of Open Access Journals (Sweden)

Alexandru Maries

2018-03-01

Full Text Available Drawing appropriate diagrams is a useful problem solving heuristic that can transform a problem into a representation that is easier to exploit for solving it. One major focus while helping introductory physics students learn effective problem solving is to help them understand that drawing diagrams can facilitate problem solution. We conducted an investigation in which two different interventions were implemented during recitation quizzes in a large enrollment algebra-based introductory physics course. Students were either (i asked to solve problems in which the diagrams were drawn for them or (ii explicitly told to draw a diagram. A comparison group was not given any instruction regarding diagrams. We developed rubrics to score the problem solving performance of students in different intervention groups and investigated ten problems. We found that students who were provided diagrams never performed better and actually performed worse than the other students on three problems, one involving standing sound waves in a tube (discussed elsewhere and two problems in electricity which we focus on here. These two problems were the only problems in electricity that involved considerations of initial and final conditions, which may partly account for why students provided with diagrams performed significantly worse than students who were not provided with diagrams. In order to explore potential reasons for this finding, we conducted interviews with students and found that some students provided with diagrams may have spent less time on the conceptual analysis and planning stage of the problem solving process. In particular, those provided with the diagram were more likely to jump into the implementation stage of problem solving early without fully analyzing and understanding the problem, which can increase the likelihood of mistakes in solutions.

Case of two electrostatics problems: Can providing a diagram adversely impact introductory physics students' problem solving performance?

Science.gov (United States)

Maries, Alexandru; Singh, Chandralekha

2018-06-01

Drawing appropriate diagrams is a useful problem solving heuristic that can transform a problem into a representation that is easier to exploit for solving it. One major focus while helping introductory physics students learn effective problem solving is to help them understand that drawing diagrams can facilitate problem solution. We conducted an investigation in which two different interventions were implemented during recitation quizzes in a large enrollment algebra-based introductory physics course. Students were either (i) asked to solve problems in which the diagrams were drawn for them or (ii) explicitly told to draw a diagram. A comparison group was not given any instruction regarding diagrams. We developed rubrics to score the problem solving performance of students in different intervention groups and investigated ten problems. We found that students who were provided diagrams never performed better and actually performed worse than the other students on three problems, one involving standing sound waves in a tube (discussed elsewhere) and two problems in electricity which we focus on here. These two problems were the only problems in electricity that involved considerations of initial and final conditions, which may partly account for why students provided with diagrams performed significantly worse than students who were not provided with diagrams. In order to explore potential reasons for this finding, we conducted interviews with students and found that some students provided with diagrams may have spent less time on the conceptual analysis and planning stage of the problem solving process. In particular, those provided with the diagram were more likely to jump into the implementation stage of problem solving early without fully analyzing and understanding the problem, which can increase the likelihood of mistakes in solutions.

Environmental problems due to mining in Jharia Coalfield

Energy Technology Data Exchange (ETDEWEB)

Banerjee, S.P.

1985-06-01

The Jharia coalfield to the NW of Calcutta, India is the most important source of coking coal in the country. Coal mining started in 1890; in 1971-3 the coking coal mines were nationalised, the remainder being operated by the Bharat Coking Coal Ltd., TISCO and IISCO. Intensive mining has resulted in major environmental problems - land damage, water pollution, air pollution and overpopulation - which a major reconstruction programme started in 1976 hopes to solve. 2 references.

Schooling in modern Europe exploring major issues and their ramifications

Science.gov (United States)

Husén, Torsten

1993-11-01

Basing its arguments on a major study conducted on behalf of the Academia Europaea by a study group coordinated by the author, this paper sets out a number of important findings concerning problems besetting schooling in modern Europe. The paper begins by stressing the importance of studying the state of European education at a particularly significant time when major political changes are taking place, trade and labour markets are in a process of rapid integration, schools as institutions are becoming increasingly complex and there is a need to establish a new European identity and consciousness. The main questions examined, against the current background of industrialization, urbanization, changing demography and growing European integration, are those relating particularly to educational response to growing international competition and the consequences of changing family structure. Among problems considered are those arising from the changing capacity of schools to provide a substitute for the family and other influences in modern society at a time when, for various reasons, these are declining and schooling is generally being prolonged. Priority areas proposed for school education in the new circumstances include the promotion of European citizenship, the teaching of foreign languages to all, a preparation for working life geared to its rapidly changing structure and the expansion of appropriate scientific and technological education. The need to find solutions to the problems of educating immigrant groups and to develop evaluation systems in order to monitor quality maintenance are particularly highlighted.

An asthma-related quality of life instrument is unable to identify asthmatic children with major psychosocial problems.

NARCIS (Netherlands)

Tibosch, M.M.; Reidsma, C.; Landstra, A.; Hugen, C.A.C.; Gerrits, P.; Brouwer, M.; Gent, R. van; Merkus, P.J.F.M.; Verhaak, C.M.

2010-01-01

Evidence shows that psychosocial problems among children and adolescents with asthma interfere with adherence to treatment and therefore need attention in asthma care. It is unknown whether the already frequently implemented asthma-related quality of life (QoL) instruments reflect psychosocial

Victimized Majority: Latent Politics of Ethnic Discrimination in post-Soviet Russia

Directory of Open Access Journals (Sweden)

Kirill N. Babichenko

2014-07-01

Full Text Available This paper represents the brief analysis of one of the most important problems of the Russian Federation – the ethnic conflicts. Such a phenomenon has various dimensions and manifestations: from discrimination on the labor market to the extreme of ethnic cleansing during wars in Chechnya. The author focuses on the previously unexplored side of the problem: structural oppression conducted by minorities against the cultural majority of the country with a special regard to the republics of North Caucasus where the scope and intensity of ethnic strife found the most dangerous and explosive forms threatening with disintegration of the state.

MOTIVATION, A BRIDGE FOR NON-ENGLISH MAJOR FRESHMEN IN THEIR TRANSITION

Institute of Scientific and Technical Information of China (English)

2000-01-01

This study intends to examine the problems that affected non-English major freshmen’s motivation and the potential factors that could influence their motivation, intrinsic or extrinsic. Self-report data were collected from 188 freshmen selected randomly in Nanchang College by using a close-ended questionnaire. Qualitative results came from interviews with 8 freshmen and 5 teachers. Findings provide evidence that some problems, which emerge with the transition from middle school to college, will influence students’ motivation. Meanwhile, intrinsic motivation can be boosted if the factors of goal, attitude, self-confidence, self-determination, learning environment, learning strategies, teaching methods are valued by teachers.

Multi-grid and ICCG for problems with interfaces

International Nuclear Information System (INIS)

Dendy, J.E.; Hyman, J.M.

1980-01-01

Computation times for the multi-grid (MG) algorithm, the incomplete Cholesky conjugate gradient (ICCG) algorithm [J. Comp. Phys. 26, 43-65 (1978); Math. Comp. 31, 148-162 (1977)], and the modified ICCG (MICCG) algorithm [BIT 18, 142-156 (1978)] to solve elliptic partial differential equations are compared. The MICCG and ICCG algorithms are more robust than the MG for general positive definite systems. A major advantage of the MG algorithm is that the structure of the problem can be exploited to reduce the solution time significantly. Five example problems are discussed. For problems with little structure and for one-shot calculations ICCG is recommended over MG, and MICCG, over ICCG. For problems that are done many times, it is worth investing the effort to study methods like MG. 1 table

Service Member Suicide and Readiness: An Analysis

Science.gov (United States)

2017-05-25

command, and degrades the morale of those still serving, as well as the American public.8 A shrinking number of qualified volunteers and reductions...to Sri Aurobindo’s Philosophy of Integral Non-Dualism,” in The Integral Philosophy of Sri Aurobindo, ed. Haridas Chaudhuri and Frederic Spiegelberg...potentially unsolvable problem should not prevent attempts to develop solutions. In a moral sense, service member suicide should elicit greater diligence

Contribution of Neutrophils to Acute Lung Injury

OpenAIRE

Grommes, Jochen; Soehnlein, Oliver

2010-01-01

Treatment of acute lung injury (ALI) and its most severe form, acute respiratory distress syndrome (ARDS), remain unsolved problems of intensive care medicine. ALI/ARDS are characterized by lung edema due to increased permeability of the alveolar-capillary barrier and subsequent impairment of arterial oxygenation. Lung edema, endothelial and epithelial injury are accompanied by an influx of neutrophils into the interstitium and broncheoalveolar space. Hence, activation and recruitment of neut...

[Inflammatory granulomas in the pathology of the nervous system. General remarks].

Science.gov (United States)

Tommasi, M

1976-01-01

The "gliogenic" participation in the edification of granulomas may produce peculiar morphological features especially in the central nervous system, and perhaps more than elsewhere, pseudotumoral features. Moreover, the concept of "granuloma" is perhaps not as well defined as in the other tissues. There are also some still unsolved problems concerning the histogenesis of the cells of the "granuloma". Some examples taken among the different etiologies illustrate these notions.

Numerical relativity

International Nuclear Information System (INIS)

Piran, T.

1982-01-01

There are many recent developments in numerical relativity, but there remain important unsolved theoretical and practical problems. The author reviews existing numerical approaches to solution of the exact Einstein equations. A framework for classification and comparison of different numerical schemes is presented. Recent numerical codes are compared using this framework. The discussion focuses on new developments and on currently open questions, excluding a review of numerical techniques. (Auth.)

Constrained potential method for false vacuum decays

International Nuclear Information System (INIS)

Park, Jae-hyeon

2010-11-01

A procedure is reported for numerical analysis of false vacuum transition in a model with multiple scalar fields. It is a refined version of the approach by Konstandin and Huber. The alteration makes it possible to tackle a class of problems that was difficult or unsolvable with the original method, i.e. those with a distant or nonexistent true vacuum. An example with an unbounded-from-below direction is presented. (orig.)

Do Biology Majors Really Differ from Non-STEM Majors?

Science.gov (United States)

Cotner, Sehoya; Thompson, Seth; Wright, Robin

2017-01-01

Recent calls to action urge sweeping reform in science education, advocating for improved learning for all students-including those majoring in fields beyond the sciences. However, little work has been done to characterize the differences-if any exist-between students planning a career in science and those studying other disciplines. We describe an attempt to clarify, in broad terms, how non-STEM (science, technology, engineering, and mathematics) majors differ from life sciences majors, and how they are similar. Using survey responses and institutional data, we find that non-STEM majors are not unilaterally science averse; non-STEM majors are more likely than biology majors to hold misconceptions about the nature of science, yet they are not completely ignorant of how science works; non-STEM majors are less likely than biology majors to see science as personally relevant; and non-STEM majors populations are likely to be more diverse-with respect to incoming knowledge, perceptions, backgrounds, and skills-than a biology majors population. We encourage science educators to consider these characteristics when designing curricula for future scientists or simply for a well-informed citizenry. © 2017 S. Cotner et al. CBE—Life Sciences Education © 2017 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Advanced sampling theory with applications how Michael ‘selected’ Amy

CERN Document Server

Singh, Sarjinder

2003-01-01

This book is a multi-purpose document. It can be used as a text by teachers, as a reference manual by researchers, and as a practical guide by statisticians. It covers 1165 references from different research journals through almost 1900 citations across 1194 pages, a large number of complete proofs of theorems, important results such as corollaries, and 324 unsolved exercises from several research papers. It includes 159 solved, data-based, real life numerical examples in disciplines such as Agriculture, Demography, Social Science, Applied Economics, Engineering, Medicine, and Survey Sampling. These solved examples are very useful for an understanding of the applications of advanced sampling theory in our daily life and in diverse fields of science. An additional 173 unsolved practical problems are given at the end of the chapters. University and college professors may find these useful when assigning exercises to students. Each exercise gives exposure to several complete research papers for researchers/stude...

At the threshold to a new world

International Nuclear Information System (INIS)

Boeer, K.W.

1993-01-01

The rapidly declining ecological health of the globe and its contributing factors are reviewed, and a global health index is defined that helps visualizing approaching danger points. The close relationship between ecologically declining health, the need for more energy per capita world-wide and the economic growth as a driving force are discussed. Large scale reforestation to counteract greenhouse gas imbalance is described as temporary aid to buy time and avoid instabilities in weather patterns until more permanent solutions can be in place that permit further economic growth of the total gross world product. The only feasible solution that does not mortgage future generations with yet unsolved, and possibly unsolvable problems is the massive deployment of solar conversion equipment. The use of photovoltaic panels is a well established technology and is described as a totally benign solution that, in conjunction with hydrogen storage, can be used as the dominant future source of energy on earth

A new technology for concentrating and solidifying liquid LLRW

Energy Technology Data Exchange (ETDEWEB)

Newell, N. [TMC, Inc., Portland, OR (United States); Osborn, M.W.; Carey, C.C. [Oregon Health Sciences Univ., Portland, OR (United States)] [and others

1995-12-31

One of the unsolved problem areas of low level radioactive waste management is the radiolabeled material generated by life sciences research and clinical diagnostics. In hundreds of academic, biotechnology, and pharmaceutical institutions, there exists large amounts of both aqueous and organic solutions containing radioactively labeled nucleic acids, proteins, peptides, and their monomeric components. We have invented a generic slurry capable of binding all these compounds, thus making it possible to concentrate and solidify the radioactive molecules into a very small and lightweight material. The slurry can be contained in both large and small disposal plastic devices designed for the size of any particular operation. The savings in disposal costs and convenience of this procedure is a very attractive alternative to the present methods of long and short term storage. Additionally, the slurry can remove radiolabeled biological compounds from organic solvents, thus solving the major problem of {open_quotes}mixed{close_quotes} waste. We are now proceeding with the field application stage for the testing of these devices and anticipate widespread use of the process. We also are exploring the use of the slurry on other types of liquid low level radioactive waste.

Why threefold-replication of families?

Science.gov (United States)

Fitzpatrick, Gerald L.

1998-04-01

In spite of the many successes of the standard model of particle physics, the observed proliferation of matter-fields, in the form of ``replicated'' generations or families, is a major unsolved problem. In this paper, I explore some of the algebraic, geometric and physical consequences of a new organizing principle for fundamental fermions (quarks and leptons)(Gerald L. Fitzpatrick, phThe Family Problem--New Internal Algebraic and Geometric Regularities), Nova Scientific Press, Issaquah, Washington, 1997. Read more about this book (ISBN 0--9655695--0--0) and its subject matter at: http://www.tp.umu.se/TIPTOP and/or amazon.com>http://www.amazon.com.. The essence of the new organizing principle is the idea that the standard-model concept of scalar fermion numbers f can be generalized. In particular, a ``generalized fermion number,'' which consists of a 2× 2 matrix F that ``acts'' on an internal 2-space, instead of spacetime, is taken to describe certain internal properties of fundamental fermions. This generalization automatically introduces internal degrees of freedom that ``explain,'' among other things, family replication and the number (three) of families observed in nature.

Thin Client Architecture: The Promise and the Problems.

Science.gov (United States)

Machovec, George S.

1997-01-01

Describes thin clients, a networking technology that allows organizations to provide software applications over networked workstations connected to a central server. Topics include corporate settings; major advantages, including cost effectiveness and increased computer security; problems; and possible applications for large public and academic…

Problems of realization of the rights of victims of crimes to compensation by the state

Directory of Open Access Journals (Sweden)

Н. А. Хмельова

2015-05-01

Full Text Available Problem setting: consider the problems of realization of the rights of victims of crime persons to compensation by the State under the laws of Ukraine. To analyze the current civil legislation of Ukraine, to consider the legislation of the countries in terms of state compensation for damages caused to the victim crime. Suggest a mechanism to implement them. Recent research and publications analysis: some aspects of state compensation for harm caused to the victim crime investigated by many scientists. Thus, O. Vedernikova, O. Kuchinska, A. Mazalov, V. Sawickiy in his scientific studies have concentrated on the investigation of the creation of a state fund damages caused offense. R. Abramovich’s work explored the issue of compensation to the victim harm caused by crime as a legal obligation of the State on the basis of mutual responsibility of the citizen to the state and the state before a national. D. Plachkov investigated features of state obligations arising from causing offense, the specific legal solution of the relations in Ukraine. Paper objective: identifying challenges the rights of victims of crime persons to compensation by the state will set features the state’s obligations arising from causing crime and identify ways to improve the legal regulation of the relations in Ukraine. Paper main body: the current civil legislation of Ukraine stipulates the right of victims of criminal offenses on the restoration of rights violations. But there are cases where recovery is impossible. The reasons for this is that, first, is guilty of a criminal offense a person is insolvent, and the actual recovery of funds it usually extends over many years and is irregular. Secondly, the problem relates stopped criminal proceedings in which a person has committed a criminal offense is not established and the victim is deprived of right to file a civil action. Thirdly, the remedy is not possible victims in unsolved criminal offenses, such as when a

On Babies and Bathwater: Addressing the Problems of Identification of Learning Disabilities.

Science.gov (United States)

Scruggs, Thomas E.; Mastropieri, Margo A.

2002-01-01

This article reviews problems in identification of learning disabilities and considers proposed alternatives to present procedures. It argues that the major problems of over identification, variability, and specificity, can be eliminated by increasing specificity and consistency of state criteria and strict adherence to identification criteria on…

Numerical Methods for Solution of the Extended Linear Quadratic Control Problem

DEFF Research Database (Denmark)

Jørgensen, John Bagterp; Frison, Gianluca; Gade-Nielsen, Nicolai Fog

2012-01-01

In this paper we present the extended linear quadratic control problem, its efficient solution, and a discussion of how it arises in the numerical solution of nonlinear model predictive control problems. The extended linear quadratic control problem is the optimal control problem corresponding...... to the Karush-Kuhn-Tucker system that constitute the majority of computational work in constrained nonlinear and linear model predictive control problems solved by efficient MPC-tailored interior-point and active-set algorithms. We state various methods of solving the extended linear quadratic control problem...... and discuss instances in which it arises. The methods discussed in the paper have been implemented in efficient C code for both CPUs and GPUs for a number of test examples....

21st century challenges and opportunities for nuclear waste management

International Nuclear Information System (INIS)

McKinley, I.G.

2009-01-01

The technical arguments for massive expansion of nuclear power generation are convincing, but such a renaissance requires public acceptance. For diehard nuclear opponents, criticism now focuses on its Achilles heel - the unsolved (and often claimed to be insoluble) problem of disposal of the resultant long-lived waste. In fact, the geological disposal of nuclear waste can be managed safely with existing technology and should really be touted as one of the advantages of this option. Clearly, there is a major challenge in communicating disposal safety to key stakeholders in order to realise this benefit. Nevertheless, the growth of environmental concern about global warming and the present economic climate may present opportunities to initiate dialogue with relevant communities, allowing the attractions of hosting future disposal facilities to be seen. Rather than being the archetypal focus for NIMBY reactions, maybe within a few years we can look forward to growing competition to host geological repositories for radioactive waste.(Author)

Experiment-based modelling of hardening and localized plasticity in metals irradiated under cascade damage conditions

International Nuclear Information System (INIS)

Singh, B.N.; Ghoniem, N.M.; Trinkaus, H.

2002-01-01

The analysis of the available experimental observations shows that the occurrence of a sudden yield drop and the associated plastic flow localization are the major concerns regarding the performance and lifetime of materials exposed to fission or fusion neutrons. In the light of the known mechanical properties and microstructures of the as-irradiated and irradiated and deformed materials, it has been argued that the increase in the upper yield stress, the sudden yield drop and the initiation of plastic flow localization, can be rationalized in terms of the cascade induced source hardening (CISH) model. Various aspects of the model (main assumptions and predictions) have been investigated using analytical calculations, 3-D dislocation dynamics and molecular dynamics simulations. The main results and conclusions are briefly summarized. Finally, it is pointed out that even though the formation of cleared channels may be rationalized in terms of climb-controlled glide of the source dislocation, a number of problems regarding the initiation and the evolution of these channels remain unsolved

Experiment-based modelling of hardening and localized plasticity in metals irradiated under cascade damage conditions

Energy Technology Data Exchange (ETDEWEB)

Singh, B.N. E-mail: bachu.singh@risoe.dk; Ghoniem, N.M.; Trinkaus, H

2002-12-01

The analysis of the available experimental observations shows that the occurrence of a sudden yield drop and the associated plastic flow localization are the major concerns regarding the performance and lifetime of materials exposed to fission or fusion neutrons. In the light of the known mechanical properties and microstructures of the as-irradiated and irradiated and deformed materials, it has been argued that the increase in the upper yield stress, the sudden yield drop and the initiation of plastic flow localization, can be rationalized in terms of the cascade induced source hardening (CISH) model. Various aspects of the model (main assumptions and predictions) have been investigated using analytical calculations, 3-D dislocation dynamics and molecular dynamics simulations. The main results and conclusions are briefly summarized. Finally, it is pointed out that even though the formation of cleared channels may be rationalized in terms of climb-controlled glide of the source dislocation, a number of problems regarding the initiation and the evolution of these channels remain unsolved.

From individual statements to market maps : a geomarketing approach to public transport Planning

Directory of Open Access Journals (Sweden)

Arnaud Banos

2002-07-01

Full Text Available Since several decades, French urbanisation evolves in a way that can hardly be seen favourable to public transportation. Innovation is needed in this field, if the individual automobile is to be faced on its own territories. This need for innovation concerns the miscellaneous stages of the public transport production, including the preliminary analysis ones. Indeed, many work remains to be done to understand mobility behaviour, what is more if we are to propose versatile and viable alternatives to current trends. Geomarketing based surveys, combining revealed and stated preferences, are a powerful way of acquiring such an accurate information. From a qualitative point of view, this kind of information allows to calibrate public transport services adapted as much as possible to the targeted customers. However, the major problem of the spatial generalisation of this individual information remains often unsolved. In this context, a strategy is proposed, based on the combination of miscellaneous methods.

QSAR Modeling: Where have you been? Where are you going to?

Science.gov (United States)

Cherkasov, Artem; Muratov, Eugene N.; Fourches, Denis; Varnek, Alexandre; Baskin, Igor I.; Cronin, Mark; Dearden, John; Gramatica, Paola; Martin, Yvonne C.; Todeschini, Roberto; Consonni, Viviana; Kuz'min, Victor E.; Cramer, Richard; Benigni, Romualdo; Yang, Chihae; Rathman, James; Terfloth, Lothar; Gasteiger, Johann; Richard, Ann; Tropsha, Alexander

2014-01-01

Quantitative Structure-Activity Relationship modeling is one of the major computational tools employed in medicinal chemistry. However, throughout its entire history it has drawn both praise and criticism concerning its reliability, limitations, successes, and failures. In this paper, we discuss: (i) the development and evolution of QSAR; (ii) the current trends, unsolved problems, and pressing challenges; and (iii) several novel and emerging applications of QSAR modeling. Throughout this discussion, we provide guidelines for QSAR development, validation, and application, which are summarized in best practices for building rigorously validated and externally predictive QSAR models. We hope that this Perspective will help communications between computational and experimental chemists towards collaborative development and use of QSAR models. We also believe that the guidelines presented here will help journal editors and reviewers apply more stringent scientific standards to manuscripts reporting new QSAR studies, as well as encourage the use of high quality, validated QSARs for regulatory decision making. PMID:24351051

Hydrogen bonds and heat diffusion in α-helices: a computational study.

Science.gov (United States)

Miño, German; Barriga, Raul; Gutierrez, Gonzalo

2014-08-28

Recent evidence has shown a correlation between the heat diffusion pathways and the known allosteric communication pathways in proteins. Allosteric communication in proteins is a central, yet unsolved, problem in biochemistry, and the study and characterization of the structural determinants that mediate energy transfer among different parts of proteins is of major importance. In this work, we characterized the role of hydrogen bonds in diffusivity of thermal energy for two sets of α-helices with different abilities to form hydrogen bonds. These hydrogen bonds can be a constitutive part of the α-helices or can arise from the lateral chains. In our in vacuo simulations, it was observed that α-helices with a higher possibility of forming hydrogen bonds also had higher rates of thermalization. Our simulations also revealed that heat readily flowed through atoms involved in hydrogen bonds. As a general conclusion, according to our simulations, hydrogen bonds fulfilled an important role in heat diffusion in structural patters of proteins.

Exploring the dark side of the Universe

International Nuclear Information System (INIS)

Das, Mala

2014-01-01

Astronomical observations show that about 95% of the energy density of the Universe cannot be accounted for in terms of mass and energy of which about 26.8% is considered to be dark matter. The detection of this dark matter is one of the major and interesting unsolved problems in Physics. There are many experiments running worldwide at different underground laboratories for the direct detection of dark matter, mainly WIMPs (Weakly Interacting Massive Particles), the most favoured candidate of dark matter. Direct detection experiments expect to detect the dark matter directly by measuring the small energy imparted to recoil nuclei in occasional dark matter interactions with detector, stationed at earth's laboratory. In the subsequent sections, the challenges of such experiments are discussed followed by the details on PICASSO/PICO dark matter search experiment at SNO Lab, activities related to this experiment at SINP and the future direction of dark matter experiments

The steady-state tangential contact problem for a falling drop type of contact area on corrugated rail by simplified theory of rolling contact

Science.gov (United States)

Piotrowski, Jerzy

1991-10-01

Investigation of contact mechanical nonlinearities of a mathematical model of corrugation revealed that the typical shape of contact patch resembles a falling drop of water. A contact patch of that shape was approximated with a figure composed of two parts of ellipses with different eccentricities. The contact pressure distribution was assumed as a smoothing ensemble of two paraboloidal distributions. The description of a general case of double half elliptical contact area was given but a special case of double half elliptical contact is more interesting as it possesses some Hertzian properties. It was shown how three geometrical parameters of double half elliptical contact can be chosen when actual, non-Hertzian contact is known. A linear theory was written which indicates that the lateral vibrations of the rail may be excited only due to shape variation on corrugation even if any other cause for these vibrations does not exist. For nonlinear theory a computer program, based on FASTSIM algorithm by Kalker, was written. The aim is to calculate the creep forces and frictional power density distribution over the contact area. Also, a graphic program visualizing the solution was written. Numerical results are not provided; unattended and unsolved problems relevant for this type of contact are listed.

Collaborative Management of Complex Major Construction Projects: AnyLogic-Based Simulation Modelling

Directory of Open Access Journals (Sweden)

Na Zhao

2016-01-01

Full Text Available Complex supply chain system collaborative management of major construction projects effectively integrates the different participants in the construction project. This paper establishes a simulation model based on AnyLogic to reveal the collaborative elements in the complex supply chain management system and the modes of action as well as the transmission problems of the intent information. Thus it is promoting the participants to become an organism with coordinated development and coevolution. This study can help improve the efficiency and management of the complex system of major construction projects.

On accuracy problems for semi-analytical sensitivity analyses

DEFF Research Database (Denmark)

Pedersen, P.; Cheng, G.; Rasmussen, John

1989-01-01

The semi-analytical method of sensitivity analysis combines ease of implementation with computational efficiency. A major drawback to this method, however, is that severe accuracy problems have recently been reported. A complete error analysis for a beam problem with changing length is carried ou...... pseudo loads in order to obtain general load equilibrium with rigid body motions. Such a method would be readily applicable for any element type, whether analytical expressions for the element stiffnesses are available or not. This topic is postponed for a future study....

BIO-ECOLGICAL PHENOMENON OF POLY-PARASITISM – ACTUAL MAJOR PROBLEM IN BREEDING OF SHEEP AND GOATS

Directory of Open Access Journals (Sweden)

DOINA ARDELEANU

2007-10-01

Full Text Available The paper presents the results of a extensive study concerning the parasites andcomplexe problems of the poly-parasitism on sheep and goats in Dobrudja. In thispaper we proposed ourselves to establish the sheep and goats endoparasites, thedistribution and frequency of these function to age, sex and maintenance conditions.The increase of morbidity through parasitical diseases, as well as the ecological andeconomic consequences of poly-parasitism represent a important problem in theintegration conditions of Romania in UE and imposes to apply some efficientmethods of prophylaxis and control of parasitosis and parasito- zoonozis. Thedrawing of copro-parazitologic samples was effected directly from rectum of sheepand goats, testing 10% of each lot, during grazing season and in period of keepingin sheds. The copro-parasitological examinations were carried out ovoscopicaly(flotation, by next methods: Willis, Mc. Master and sediment, by Benedect-Nemesseri and polyvalent methods, as well as larvoscopicaly by Baermann method.After copro-parasitological examinations of samples which were harvested fromthese animals it comes out that both sheep and goats presents poly-parasitism withsporozoa (coccidiae: Eimeria spp. , cestodae (Moniezia expansa and Monieziabenedeni, gastro-intestinal nematodes (Nematodirus spp. ,Trichostrongylidae,Strongyloides papillosus and pulmonary nematodes (Protostrongylus rufescens,Dictyocaulus filaria, Muellerius capillaris, the degree of parasitical infestationdepending on species, age, sex, maintenance conditions and environmental factors.

Oil and gas: year full of major events and dramatic changes

International Nuclear Information System (INIS)

Hirman, K.

2004-01-01

European gas industry encountered a historical precedent this February. Russian gas concern Gazprom has for the first time in its over thirty-year history of gas delivery from Siberia to Europe deliberately stopped the export. Even though this did not last for more then one day, customers in Latvia immediately noticed problems and also Polish customers mentioned some losses. Slovakia, still fully dependent on Russian gas supplies and at the same time major transported of Russian gas to European, was not touched by this situation as the deliveries were stopped on gas pipeline Jamal-Europe delivering gas to Germany through Belarus and Poland. But this affair can become a major issue in gas and political relations between Russia, Belarus and Ukraine and can also have a long-term impact on a dialog between Europe and Russia and consequently on building of new gas pipelines. And that could have a major impact on Slovakia's position as a transit country. Important for Slovakia is also the ongoing discussion about Ukrainian pipeline Odessa-Brody. A political decision made by Ukrainian cabinet that this pipeline should only be used to transport oil from Caspian Sea can give Slovakia the opportunity to diversify its oil import and at the same time increase the transit volumes should German refineries show interest in this transit route. On the other hand ratification of an intergovernmental agreement on integration of pipelines Druzba and Adria by Ukrainian Parliaments is also good news for Bratislava. This step politically opened the possibility to deliver Russian oil through Slovakia to Croatian Omisajl and from there with tankers to Europe and Northern America. The capacity of pipeline Druzba in Ukraine and Slovakia is not sufficient to take both the increased volumes of Russian and Caspian oil these two projects are competing for the free capacity. And the process and outcome of this competition may be of direct influence on Slovak interests. At the moment there are

Data-Driven Model Order Reduction for Bayesian Inverse Problems

KAUST Repository

Cui, Tiangang; Youssef, Marzouk; Willcox, Karen

2014-01-01

One of the major challenges in using MCMC for the solution of inverse problems is the repeated evaluation of computationally expensive numerical models. We develop a data-driven projection- based model order reduction technique to reduce

Problems and challenges in social marketing.

Science.gov (United States)

Bloom, P N; Novelli, W D

1981-01-01

This article reviews the problems that arise when general marketing principles are applied to social programs. Social marketing is conceptualized as the design, implementation, and control of programs seeking to increase the acceptability of a social ideal or practice in a target group. These problems can occur in 8 basic decision-making areas: market analysis, market segmentation, product strategy development, pricing strategy development, channel strategy development, communications strategy development, organizational design and planning, and evaluation. Social marketers find that they have less good secondary data about their consumers, more problems obtaining valid and reliable measures of relevant variables, more difficulty sorting out the relative influence of determinants of consumer behavior, and more problems getting consumer research funded than marketers in the commercial sector. They tend to have less flexibility in shaping their products and more difficulty formulating product concepts. Problems associated with establishing, utilizing, and controlling distribution channels comprise another major difference between social and more conventional forms of marketing. Social marketers also find that their communications options are somewhat limited as a result of problems associated with use of paid advertisements, pressures not to use certain types of appeals in their messages, and the need to communicate large amounts of information in their messages. Moreover, social marketers must function in organizations where marketing activities are poorly understood, underappreciated, and inappropriately located. Finally, they face problems trying to define effectiveness measures or estimating the contribution their program has made toward the achievement of certain objectives. If all these problems are anticipated and handled creatively, social marketing efforts can succeed.

The computation of bond percolation critical polynomials by the deletion–contraction algorithm

International Nuclear Information System (INIS)

Scullard, Christian R

2012-01-01

Although every exactly known bond percolation critical threshold is the root in [0,1] of a lattice-dependent polynomial, it has recently been shown that the notion of a critical polynomial can be extended to any periodic lattice. The polynomial is computed on a finite subgraph, called the base, of an infinite lattice. For any problem with exactly known solution, the prediction of the bond threshold is always correct for any base containing an arbitrary number of unit cells. For unsolved problems, the polynomial is referred to as the generalized critical polynomial and provides an approximation that becomes more accurate with increasing number of bonds in the base, appearing to approach the exact answer. The polynomials are computed using the deletion–contraction algorithm, which quickly becomes intractable by hand for more than about 18 bonds. Here, I present generalized critical polynomials calculated with a computer program for bases of up to 36 bonds for all the unsolved Archimedean lattices, except the kagome lattice, which was considered in an earlier work. The polynomial estimates are generally within 10 −5 –10 −7 of the numerical values, but the prediction for the (4,8 2 ) lattice, though not exact, is not ruled out by simulations. (paper)

Proven Techniques: The Use and Impact of Major Management Concepts in Community Colleges.

Science.gov (United States)

Deegan, William L.

1992-01-01

Describes a survey of community college presidents' use of and perception of the effectiveness of major management concepts related to planning, organization, budgeting/finance, staffing, and evaluation. Also summarizes presidents' perceptions of the problems facing them and their perspectives on the future. (DMM)

Surveying Turkish High School and University Students' Attitudes and Approaches to Physics Problem Solving

Science.gov (United States)

Balta, Nuri; Mason, Andrew J.; Singh, Chandralekha

2016-01-01

Students' attitudes and approaches to physics problem solving can impact how well they learn physics and how successful they are in solving physics problems. Prior research in the U.S. using a validated Attitude and Approaches to Problem Solving (AAPS) survey suggests that there are major differences between students in introductory physics and…

Mental health problems among children and adolescents experiencing two major earthquakes in remote mountainous regions: A longitudinal study.

Science.gov (United States)

Tang, Wanjie; Zhao, Jingdong; Lu, Yi; Yan, Tingting; Wang, Lijuan; Zhang, Jun; Xu, Jiuping

2017-01-01

Millions of children were exposed to major earthquake in China, with serious psychological and developmental consequences. To obtain accurate rate of post-disaster related disorder and identify predictors may help inform post-disaster rescue and rehabilitation efforts. The present longitudinal study explored correlations of demographic and socioeconomic characteristics of juvenile survivors of the Ya'an and Wenchuan earthquakes in China with their trajectories of post-disaster related disorder. A total of 435 Chinese children and adolescents who survived the 2013 Ya'an earthquake were recruited from six primary, secondary and high schools in Baoxing County. All survivors were assessed at 12months after the disaster, when a trained psychiatrist assessed mental health problems in a face-to-face structured interview, and 153 survivors were followed up at 30months after the earthquake via telephone. The 12-month assessment indicated a post-traumatic stress disorder (PTSD) prevalence of 43.9% as well as depression (20.9%) or the criteria for both PTSD and depression (18.2%) and the other disorder (0.9%). The 30-month assessment indicated that 15.7% of subjects met the criteria for PTSD, 21.6% met the criteria for depression. No subjects met the criteria for other affective or anxiety disorders. Significant predictors of PTSD and depression were death in the family, previous earthquake experience, a poor parent-child relationship and economic pressure or poverty. Clinical interview face to face is quite different from via telephone and the attrition rate in the longitudinal cohort is high, which would directly affect our results of the assessment. PTSD and depression may be as prevalent and persistent in disaster victims in China as elsewhere, and high co-comorbidities remain poorly understood. Although many adolescents recover over time, some exhibit chronic, delayed-onset PTSD and depression, especially those with poor relationships with their parents or those living

Messy Problems and Lay Audiences: Teaching Critical Thinking within the Finance Curriculum

Science.gov (United States)

Carrithers, David; Ling, Teresa; Bean, John C.

2008-01-01

This article investigates the critical thinking difficulties of finance majors when asked to address ill-structured finance problems. The authors build on previous research in which they asked students to analyze an ill-structured investment problem and recommend a course of action. The results revealed numerous critical thinking weaknesses,…

Acute pesticide poisoning--a global public health problem

DEFF Research Database (Denmark)

Konradsen, Flemming

2007-01-01

Acute pesticide poisoning has become a major public health problem worldwide, following the intensification of agriculture and the promotion of agro-chemicals in low and middle income countries, with more than 300,000 deaths each year. The easy availability of highly toxic pesticides in the homes...... of farming communities has made pesticides the preferred means of suicide with an extremely high case fatality. Similarly, the extensive use of pesticides exposes the community to both long-term and acute occupational health problems. A concerted effort is urgently needed to address the situation....

RTD problems at Darlington

International Nuclear Information System (INIS)

McAllindon, D.; Sloan, D.; Mayer, P.

1997-01-01

Resistance Temperature Detectors (RTDs) and their measurement circuit components have been a significant maintenance item at Darlington. Analysis of the problems has shown that RTDs and electrical penetrations (EPs) have been the largest sources of faults. A failure mechanism in which the RTD electrical resistance shifts upward was identified as a major source of RTD failures, which prompted a detailed failure investigation by Ontario Hydro Technologies (OHT). The investigation concluded that the root cause failure mechanism is chlorine contamination of the platinum wire during manufacture which resulted in surface damage to the wire and flaking of the wire surface during operation. Electrical penetrations in Darlington are of a pre-built modular design with two crimps internal to the EP. Spurious resistance in poor quality crimps in the EPs lead to errors in resistance measurement. The problem led to a complex and costly job to insert new modules in existing spare EPs. (author)

Lorentz covariant tempered distributions in two-dimensional space-time

International Nuclear Information System (INIS)

Zinov'ev, Yu.M.

1989-01-01

The problem of describing Lorentz covariant distributions without any spectral condition has hitherto remained unsolved even for two-dimensional space-time. Attempts to solve this problem have already been made. Zharinov obtained an integral representation for the Laplace transform of Lorentz invariant distributions with support in the product of two-dimensional future light cones. However, this integral representation does not make it possible to obtain a complete description of the corresponding Lorentz invariant distributions. In this paper the author gives a complete description of Lorentz covariant distributions for two-dimensional space-time. No spectral conditions is assumed

Diffraction of a plane wave on two-dimensional conductive structures and a surface wave

Science.gov (United States)

Davidovich, Mikhael V.

2018-04-01

We consider the structures type of two-dimensional electron gas in the form of a thin conductive, in particular, graphene films described by tensor conductivity, which are isolated or located on the dielectric layers. The dispersion equation for hybrid modes, as well as scattering parameters. We show that free wave (eigenwaves) problem follow from the problem of diffraction when linking the amplitude of the current of the linear equations are unsolvable, i.e., the determinant of this system is zero. As a particular case the dispersion equation follow from the conditions of matching (with zero reflection coefficient).

Simplified two and three dimensional HTTR benchmark problems

International Nuclear Information System (INIS)

Zhang Zhan; Rahnema, Farzad; Zhang Dingkang; Pounders, Justin M.; Ougouag, Abderrafi M.

2011-01-01

To assess the accuracy of diffusion or transport methods for reactor calculations, it is desirable to create heterogeneous benchmark problems that are typical of whole core configurations. In this paper we have created two and three dimensional numerical benchmark problems typical of high temperature gas cooled prismatic cores. Additionally, a single cell and single block benchmark problems are also included. These problems were derived from the HTTR start-up experiment. Since the primary utility of the benchmark problems is in code-to-code verification, minor details regarding geometry and material specification of the original experiment have been simplified while retaining the heterogeneity and the major physics properties of the core from a neutronics viewpoint. A six-group material (macroscopic) cross section library has been generated for the benchmark problems using the lattice depletion code HELIOS. Using this library, Monte Carlo solutions are presented for three configurations (all-rods-in, partially-controlled and all-rods-out) for both the 2D and 3D problems. These solutions include the core eigenvalues, the block (assembly) averaged fission densities, local peaking factors, the absorption densities in the burnable poison and control rods, and pin fission density distribution for selected blocks. Also included are the solutions for the single cell and single block problems.

Quantum integrable models of field theory

International Nuclear Information System (INIS)

Faddeev, L.D.

1979-01-01

Fundamental features of the classical method of the inverse problem have been formulated in the form which is convenient for its quantum reformulation. Typical examples are studied which may help to formulate the quantum method of the inverse problem. Examples are considered for interaction with both attraction and repulsion at a final density. The sine-Gordon model and the XYZ model from the quantum theory of magnetics are examined in short. It is noted that all the achievements of the one-dimensional mathematical physics as applied to exactly solvable quantum models may be put to an extent within the framework of the quantum method of the inverse problem. Unsolved questions are enumerated and perspectives of applying the inverse problem method are shown

Major trends in nuclear and coal fired plants economics

International Nuclear Information System (INIS)

Benson, P.H.; Frank, J.R.; Isacson, H.R.

1984-01-01

An in-depth analysis of nuclear plant performance in the United States and elsewhere raises basic questions as to the validity of the present pessimism as a guide for long-range policy. The sad story of the plants in trouble has obscured the good performance of the majority of nuclear power installations. Further, it appears that many of the root causes for the outstanding problems may be indigenous to the existing U.S. utility, regulatory, and financial structure, and not relevant to the long-range intrinsic values of nuclear power either in the United States or in other countries. On the other hand, many of the problems affecting coal fired plants, i.e., fuel supply, economics and pollution control appear to be more critical abroad rather than in the U.S. This paper will review these issues

Winter treatments against the woolly apple aphid (Eriosoma lanigerum): products and timing of applications

OpenAIRE

Kelderer, Markus; Lardschneider, Ewald; Casera, Claudio

2008-01-01

In organic apple growing the woolly apple aphid (Eriosoma lanigerum) is still an unsolved problem. Various approaches to use beneficial insects were not really effective. Only winter treatments with mineral oils showed partial and fluctuating success. In 2006 and 2007 field trials were carried out to evaluate the efficacy of winter treatments to control woolly apple aphids. The efficacy of several products (different mineral oils, lime sulphur, and lime sulphur + mineral oil) w...

An Intelligent Information Retrieval Approach Based on Two Degrees of Uncertainty Fuzzy Ontology

OpenAIRE

Maryam Hourali; Gholam Ali Montazer

2011-01-01

In spite of the voluminous studies in the field of intelligent retrieval systems, effective retrieving of information has been remained an important unsolved problem. Implementations of different conceptual knowledge in the information retrieval process such as ontology have been considered as a solution to enhance the quality of results. Furthermore, the conceptual formalism supported by typical ontology may not be sufficient to represent uncertainty information due to the lack of clear-cut ...

Parameter study of electric power production in wind farms - experiments using two model scale wind turbines

OpenAIRE

Ceccotti, Clio

2015-01-01

Wind farms are widely developed even if several unsolved problems need to be faced. The rotor-wake interaction involves different physical phenomena, not yet fully understood, directly affecting the overall wind farm power production. Numerical models and engineering rules have always been used to design wind farm layout but a spread between power predictions and results is verified. In this context wind energy research assumes a "back to basic" approach, by means of wind tunne...

Analysis and outlook of applications of blockchain technology to equity crowdfunding in China

OpenAIRE

Zhu, Huasheng; Zhou, Zach Zhizhong

2016-01-01

Equity crowdfunding via the Internet is a new channel of raising money for startups. It features low barriers to entry, low cost, and high speed, and thus encourages innovation. In recent years, equity crowdfunding in China has experienced some developments. However, some problems remain unsolved in practice. Blockchain is a decentralized and distributed ledger technology to ensure data security, transparency, and integrity. Because it cannot be tampered with or forged, the technology is deem...

Testing Scientific Software: A Systematic Literature Review

Science.gov (United States)

Kanewala, Upulee; Bieman, James M.

2014-01-01

Context Scientific software plays an important role in critical decision making, for example making weather predictions based on climate models, and computation of evidence for research publications. Recently, scientists have had to retract publications due to errors caused by software faults. Systematic testing can identify such faults in code. Objective This study aims to identify specific challenges, proposed solutions, and unsolved problems faced when testing scientific software. Method We conducted a systematic literature survey to identify and analyze relevant literature. We identified 62 studies that provided relevant information about testing scientific software. Results We found that challenges faced when testing scientific software fall into two main categories: (1) testing challenges that occur due to characteristics of scientific software such as oracle problems and (2) testing challenges that occur due to cultural differences between scientists and the software engineering community such as viewing the code and the model that it implements as inseparable entities. In addition, we identified methods to potentially overcome these challenges and their limitations. Finally we describe unsolved challenges and how software engineering researchers and practitioners can help to overcome them. Conclusions Scientific software presents special challenges for testing. Specifically, cultural differences between scientist developers and software engineers, along with the characteristics of the scientific software make testing more difficult. Existing techniques such as code clone detection can help to improve the testing process. Software engineers should consider special challenges posed by scientific software such as oracle problems when developing testing techniques. PMID:25125798

Testing Scientific Software: A Systematic Literature Review.

Science.gov (United States)

Kanewala, Upulee; Bieman, James M

2014-10-01

Scientific software plays an important role in critical decision making, for example making weather predictions based on climate models, and computation of evidence for research publications. Recently, scientists have had to retract publications due to errors caused by software faults. Systematic testing can identify such faults in code. This study aims to identify specific challenges, proposed solutions, and unsolved problems faced when testing scientific software. We conducted a systematic literature survey to identify and analyze relevant literature. We identified 62 studies that provided relevant information about testing scientific software. We found that challenges faced when testing scientific software fall into two main categories: (1) testing challenges that occur due to characteristics of scientific software such as oracle problems and (2) testing challenges that occur due to cultural differences between scientists and the software engineering community such as viewing the code and the model that it implements as inseparable entities. In addition, we identified methods to potentially overcome these challenges and their limitations. Finally we describe unsolved challenges and how software engineering researchers and practitioners can help to overcome them. Scientific software presents special challenges for testing. Specifically, cultural differences between scientist developers and software engineers, along with the characteristics of the scientific software make testing more difficult. Existing techniques such as code clone detection can help to improve the testing process. Software engineers should consider special challenges posed by scientific software such as oracle problems when developing testing techniques.

A new evolutionary algorithm with LQV learning for combinatorial problems optimization

International Nuclear Information System (INIS)

Machado, Marcelo Dornellas; Schirru, Roberto

2000-01-01

Genetic algorithms are biologically motivated adaptive systems which have been used, with good results, for combinatorial problems optimization. In this work, a new learning mode, to be used by the population-based incremental learning algorithm, has the aim to build a new evolutionary algorithm to be used in optimization of numerical problems and combinatorial problems. This new learning mode uses a variable learning rate during the optimization process, constituting a process known as proportional reward. The development of this new algorithm aims its application in the optimization of reload problem of PWR nuclear reactors, in order to increase the useful life of the nuclear fuel. For the test, two classes of problems are used: numerical problems and combinatorial problems. Due to the fact that the reload problem is a combinatorial problem, the major interest relies on the last class. The results achieved with the tests indicate the applicability of the new learning mode, showing its potential as a developing tool in the solution of reload problem. (author)