[From passive to active: policies for Latin American emigrants].

Science.gov (United States)

Maletta, H

1988-12-01

The conventional view of emigration holds that it represents a loss of resources from a country and that the only possible policy response is to discourage new emigration while promoting return of those who have left. A new policy is needed based on a fuller understanding of the potential benefits of emigration for the country of origin. The cost of emigration is usually counted as the loss of educational investment, the loss of labor force, and the loss of the contributions to development that would have been made by talented emigrants. But such views usually do not include a serious treatment of the economic problems of labor supply and demand in general or of skilled labor in particular. Underemployment or unemployment of highly educated persons and overproduction of educated persons are problems throughout Latin America and much of the developing world. A truer evaluation of the costs of education which considered decreasing marginal costs rather than average costs per student, nominally variable costs that actually behave as fixed costs, and an adequate assignment of costs for students leaving school before graduating would lead to much lower estimates of average cost per university student in Latin America. Significant emigration may actually result indirectly in an increase in national income by reducing pressure on the labor market and allowing wages to rise for remaining workers. Remittances for emigrants and repatriation of savings may contribute significantly to national income and balance of payments, and may compensate for or even exceed the economic losses of emigration. National policy for emigrants should aim at maximizing the economic benefits of emigration by providing incentives for the accumulation of capital obtained abroad and its transfer to the country of origin. The 1st major goal of emigration policy should be to maintain affective and social ties between the emigrant and the country of origin as a necessary condition for channeling

'Emigration is a matter of self-preservation. The working conditions . . . are killing us slowly': qualitative insights into health professional emigration from Ireland.

Science.gov (United States)

Humphries, Niamh; McAleese, Sara; Matthews, Anne; Brugha, Ruairi

2015-05-16

Achieving a sustainable health workforce involves training and retaining sufficient staff to deliver health services. The Irish health workforce is characterised by a high level of emigration of Irish-trained staff and a heavy reliance on internationally trained staff. This paper presents qualitative findings from a mixed-method study of doctors, nurses and midwives who have recently emigrated from Ireland. Using Facebook, this study elicited 556 (388 completed) responses to an exploratory mixed-method online survey in July 2014. Respondents provided rich responses to two free-text questions, one on health worker return (N = 343) and another on health professional emigration (N = 209) from the source country (Ireland). Respondents emigrated because of difficult working conditions in the Irish health system (long working hours, uncertain career progression), which compared poorly with conditions in the destination country. Respondents' experiences in the destination country vindicated the decision to emigrate and complicated the decision to return. Their return to Ireland was contingent upon significant reform of the Irish health system and an improvement in working conditions, expressed, for example, as: 'It's not about the money, it's about respect . . . we love working in medicine, but we love our families and health more' (RD283). This paper highlights that doctors, nurses and midwives are emigrating from Ireland in search of better working conditions, clear career progression pathways and a better practice environment. The question for the source country is whether it can retain and attract back emigrant doctors, nurses and midwives by matching their expectations.

Emigration dynamics: the Indian context.

Science.gov (United States)

Premi, M K; Mathur, M D

1995-01-01

This report on emigration dynamics in India opens by providing background on short- and long-distance migration to and from India in response to such events as the formation of Pakistan as well as to the policies of the British Empire and Commonwealth. Section 2 discusses India's demographic and sociocultural setting in terms of population growth, urbanization, patterns of internal migration, growth of the labor force, economic growth, poverty alleviation, health, and education. The third section describes the lack of data on international migration. Some data are available on emigrants, but the only information on return migration is that gleaned from surveys in Kerala. Section 4 considers emigration to industrialized countries and notes that it is almost exclusively permanent and largely composed of individuals with professional, technical, or managerial skills. The resulting brain drain is described as is the incidence of illegal migration. India does not create conditions from which citizens must seek asylum, rather the country has absorbed flows of refugees from Pakistan, Tibet, Bangladesh, Afghanistan, and Sri Lanka. Available data on the characteristics of emigrants and return migrants are reviewed in the next two sections, and section 7 looks at the data on financial flows gathered from macro-level estimates of remittances. Section 8 is devoted to the community, family, and individual factors which influence emigration including the networks that facilitate migration and means of meeting migration costs. The ninth section summarizes the political setting with an emphasis on the adverse reaction of Nepal to population movement from India. The final section of the report projects future population movements. It is noted that if there were no restrictions on migration, millions of Indians would emigrate to the Americas, Africa, and Australia. Whereas poverty, unemployment, and population growth will likely erode living conditions in India, the government has

THE ECONOMIC EFFECTS OF EMIGRATION OF YOUNG

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Dorel AILENEI

2015-02-01

Full Text Available Migration is one of the oldest phenomena that accompanied the development of human society, sometimes causing clashes between peoples, cultures and civilizations. Recent events or from a not too distant past of Europe show that tensions created by migratory movements often have an impact on political and economic relations between countries, cultures and religions. The Romanian reality shows that after 1989 the resident population experienced a decline. According to the National Institute of Statistics, in the period 1989-2012, Romania's population decreased by about 3.1 million, this reduction being due to both migration phenomenon and negative natural increase of population. Some statistic records also show that the extremes are usually among those who decide to emigrate. On the one hand those who are choosing this path are individuals with low income and a low or medium level of education; on the other hand, we can find the phenomenon of brain drain. It is alarming that among those who choose to emigrate are registered young people able to work, this generating the problem of funding on medium and long term the social services. Starting from such aspects, this paper aims to highlight key issues regarding the intention of emigration of highly educated young people. Using quantitative and qualitative methods the authors of this paper aim to identify some possible causes that may determine the highly educated youth to emigrate, evaluate some possible effects due to this phenomenon and to find proposals to limit the negative effects of demographic decline.

[Preventive health control of U. S. emigrants at the beginning of 20th century on the example of hotel "Emigrants" in Rijeka].

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Rotim Malvić, Jasna

2015-01-01

Rijeka inscribed herself on the list of great European emigration ports like Hamburg, Bremen, Liverpool in the end of the year 1903 when a ship of the British Cunard Line established a travel line from Rijeka to New York. Up to the year 1914, 317639 passengers - emigrants travelled to America from the port of Rijeka. The large flow of people caused problems for the city, for that reason, already in 1906 did the Hungarian ministry of home affairs started the construction of a grandiose building intended for the emigrants. When it was opened in 1908 it was named Hotel Emigrants and had a capacity of 2500 guests. The name Hotel was given to him because of the highest construction and sanitary standards applied during his construction, but also because of comfort provided for the emigrants, large bright dormitories, living rooms, one big and spacious terrace and a number of smaller ones indicated more to a touristic hotel than to a house for emigrants. Health surveillance of emigrants was performed by Dr. David Friedman, Dr. Arturo Jellouscheg and Dr. Emil Tauffer. They were in charge in front of the Maritime Gubernia in Rijeka, the U.S. consulate in Rijeka and the Adria Maritime Society. Although the city authorities and the Hungarian authorities boasted of the hotel and the rigid medical control over immigrants which was done there, American authorities have still often returned some emigrants, at the expense of the company, after inspection at Ellis Island revealing that before landing some individuals are sick.

The Export Promoting Effect of Emigration

DEFF Research Database (Denmark)

Hiller, Sanne

The theoretical claim that ethnic networks encourage trade has found broad empirical support in the literature on migration, business networks and international trade. Ethnic networks matter for the exporting firm, as they exhibit the potential to lower fixed and variable cost of exporting....... This paper provides a first attempt to identify the export-promoting effect of emigration on the firm level. Using detailed Danish firm-level data, we can parsimoniously control for export determinants other than emigration, unobserved heterogeneity at the firm level, as well as for self-selection of firms...... into exporting. Additionally accounting for taste similarity between Denmark and its trade partners, our findings suggest a positive effect of emigration on Danish manufacturing trade within Europe, thereby corroborating preceding studies on aggregate data. Nevertheless, as a novel insight, our analysis reveals...

[Emigration and immigration in Italy. (1861-2011)].

Science.gov (United States)

Pasini, Walter

2011-01-01

The creation of the Italian Kingdom was characterized by the mass emigration of Italian people, mainly peasants towards European and American destinations. Poverty, unemployment, diseases, like pellagra, malaria and tubercolosis forced millions of Italians to leave the Country. The phenomenon of emigration is usually divided in three periods: the mass emigration from 1976 to 1914, the second one between the two world wars, the third one from 1946 to 1976. In the last quarter of the 20th century the number of repatriations overcome expatriations and the number of immigrants from Albania, Romania, Senegal, Tunisia, China, Philippines grew up becoming more and more important. Italy was a country of emigrants, now is a country of immigrants. It is difficult to compare the work conditions of the Italian emigrants with the new immigrants. At the end of the 19th Century or in the first decades of the 20th Century there were no consideration for human rights, no legislations to protect workers. Immigration from North Africa and from all the low and middle income countries should be studied in all its aspects because it will characterize our future. In the new era of economical globalization, Universities should prepare the new medical doctors to extend their professional culture to a international dimension to be able to cope with the new challenges of our time.

Explaining emigration intentions and behaviour in the Netherlands, 2005-10

NARCIS (Netherlands)

van Dalen, H.P.; Henkens, K.

2013-01-01

We examined the emigration intentions of native-born Dutch residents and their subsequent emigration behaviour from 2005 to 2010. Data were collected from two surveys on emigration intentions, one conducted locally and one nationally. A number of novel results stand out. First, intentions were good

Explaining emigration intentions and behaviour in the Netherlands 2005-2010

NARCIS (Netherlands)

van Dalen, H.P.; Henkens, C.J.I.M.

2013-01-01

We examined the emigration intentions of native-born Dutch residents and their subsequent emigration behaviour from 2005 to 2010. Data were collected from two surveys on emigration intentions, one conducted locally and one nationally. A number of novel results stand out. First, intentions were good

Immigration and emigration in the Sinai Baton Blue butterfly ...

African Journals Online (AJOL)

Thus, many estimates of rates of movement are indirect and incomplete, and there is little empirical knowledge of the factors affecting immigration and emigration. I studied intensively a local population of Sinai Baton Blue butterflies in a discrete habitat patch. The study lasted the entire adult flight period, and involved almost ...

Personality and Dutch emigrants' reactions to acculturation strategies

NARCIS (Netherlands)

Bakker, Winny; Van der Zee, Karen; Van Oudenhoven, Jan Pieter

2006-01-01

This experimental questionnaire study examined individual differences in affective and normative reactions to acculturation strategies. A sample of 265 Dutch emigrants with a dual cultural background read scenarios describing the experiences of an emigrant. Eight (4 x 2) different scenario versions

Emigration dynamics from and within South Asia.

Science.gov (United States)

Shah, N M

1995-01-01

This review of current knowledge about emigration dynamics from and within South Asia (Bangladesh, India, Pakistan, and Sri Lanka) opens with a brief history of the three phases of emigration from the area since the 1830s (plantation labor; postindependence to the UK, US, Canada, and Australia; and labor migration to the oil-exporting countries). The influence of the creation of Pakistan and Bangladesh is also covered as are British colonial and commonwealth policies. It is noted that migration data are incomplete and that India exhibits an ambivalence about collecting such information. The discussion then turns to emigration since 1970 and considers permanent migration from South Asia to the traditional receivers; South Asian asylum seekers in Europe; South Asian refugees, illegal migrants, migrant workers (flows and destinations), the stock of contract migrant workers (and their characteristics); returnee migrant workers; and skill levels. Analysis is provided of macro level determinants of emigrations such as gross national product (level and growth), the general demographic and social situation, labor force growth and structure, poverty and inequality, and internal and international migration. Environmental factors causing displacement in Southern Asia include floods, cyclones, river bank erosion, drought, and desertification. Global warming could displace millions of people in the region, and development projects have contributed to displacement. The remainder of the report covers political and ethnic factors, micro-factors influencing migration decision-making, the policies of sending and receiving countries, the consequences of emigration, and the potential for migration in the future.

Sex-specific patterns in abundance, temporary emigration and survival of Indo-Pacific bottlenose dolphins (Tursiops aduncus in coastal and estuarine waters

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Kate R Sprogis

2016-02-01

Full Text Available Inherent difficulties in determining the sex of free-ranging sexually monomorphic species often prevents a sex-specific focus on estimating abundance, movement patterns and survival rates. This study provides insights into sex-specific population parameters of Indo-Pacific bottlenose dolphins (Tursiops aduncus. Systematic, boat-based photo-identification surveys (n = 417 were conducted year-round from 2007-2013 in coastal and estuarine waters off Bunbury, Western Australia. Pollock’s Robust Design was used to quantify population parameters for three datasets: i adults and juveniles combined, ii adult females and iii adult males. For all datasets, abundance estimates varied seasonally, with general highs during summer and/or autumn, and lows during winter. Dolphins had seasonally structured temporary emigration rates with similar trends between sexes. The derived return rate (1-γ’ of temporary emigrants into the study area was highest from winter to spring, indicating that dolphins had a high probability of return into the study area during spring. We suggest that the return of dolphins into the study area and increase in abundance is influenced by the breeding season (summer/autumn. Prey availability is likely a main driver responsible for the movement of dolphins out of the study area during winter. Seasonal apparent survival rates were constant and high (0.98-0.99 for all datasets. High apparent survival rates suggest there is no permanent emigration from the study area. Our sex-specific modeling approach offers a comprehensive interpretation of the population dynamics of a top predator in a coastal and estuarine environment and acts as a model for future sex-based population studies on sexually monomorphic species.

Emigrazione e sviluppo economico. (Emigration and economic growth

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C.P. KINDLEBERGER

2014-08-01

Full Text Available The paper considers the economic debate of whether emigration helps or hurts a country. This is a vital issue along the whole Mediterranean littoral from Portugal to Turkey. On one side of the debate emigration is regarded as the export of capital, inappropriate for poor countries. On the other side, it is considered to provide the benefits of getting unemployed or disguised unemployed to work. Here the arguments for and against emigration from developing countries is presented separately in static and dynamic terms. The focus is no intra-European South-North migration. It is shown that when conditions are right, large-scale migration can contribute to rapid growth in the country of immigration, based on greater supplies of labour, and in the country of origin, based on more effective resource allocation. It is argued that within certain limits emigration can be, and has been a positive force for growth in the South.JEL: O15

Emigration dynamics in the Arab region. IOM / UNFPA workshop, 7-8 October 1996, Geneva, Switzerland.

Science.gov (United States)

Appleyard, R

1996-01-01

This paper describes the four research monographs on emigration that were presented at the December 1995 Regional Workshop in the Arab Region. The workshop was an exchange of views and discussion of policy implications of emigration. Monographs were presented by Dr. Mayar Farrag on emigration in Egypt, Professor Nadji Safir on migration in the Maghreb, Dr. Setenay Shami on emigration dynamics in Jordan, and Dr. Lynn Evans on behalf of Dr. Ivy Papps on migration in Gulf Cooperation Council (GCC) countries. Dr. Farrag identified three periods of migration. During the mid-1960s to the mid-1970s, migrants were officially encouraged by Egypt to fill education positions. During the 1970s, many migrants left for the oil-producing countries on a temporary basis. Since the mid-1980s, the influences on Egyptian migration have been the economic recession and oil prices in the Gulf states, the completion of infrastructure projects in most Gulf states, and the replacement of foreign labor with nationals. Dr. Farrag recommended improving the migrants' skills in English and technology in order to maintain a dominant flow of temporary migrants to the Gulf region. Professor Safir reported that persons from the Maghreb region (Tunisia, Algeria, and Morocco) migrated to France before independence and subsequently to West Germany and the Benelux countries. Algeria had the highest migration potential, and Morocco had the highest migration. Morocco had established networks in destination countries, high population growth rates, and high unemployment. Maghreb countries are receiving migrants from the south. Professor Safir recommended regional integration. Dr. Shami separated step migration from stepwise migration, which complicates push-pull theories. Dr. Papps argued that use of foreign labor may not be the best option for development, and that sending countries should be more aware of skill needs in GCC countries.

Factors influencing trainee doctor emigration in a high income country: a mixed methods study.

Science.gov (United States)

Clarke, Nicholas; Crowe, Sophie; Humphries, Niamh; Conroy, Ronan; O'Hare, Simon; Kavanagh, Paul; Brugha, Ruairi

2017-09-25

The Global Code of Practice on the International Recruitment of Health Personnel focuses particularly on migration of doctors from low- and middle-income countries. Less is understood about migration from high-income countries. Recession has impacted several European countries in recent years, and in some cases emigration has reached unprecedented levels. This study measures and explores the predictors of trainee doctor emigration from Ireland. Using a partially mixed sequential dominant (quantitative) study design, a nationally representative sample of 893 trainee doctors was invited to complete an online survey. Of the 523 who responded (58.6% response rate), 423 were still in Ireland and responded to questions on factors influencing intention to practice medicine abroad and are the subjects of this study. Explanatory factors for intention to practice medicine in Ireland in the foreseeable future, the primary outcome, included demographic variables and experiences of working within the Irish health system. Associations were examined using univariable and multivariable logistic regression to estimate odds ratios for factors influencing the primary outcome. Qualitative interviews were conducted with 50 trainee doctors and analysed thematically, exploring issues associated with intention to practice medicine abroad. There were high levels of dissatisfaction among trainee doctors around working conditions, training and career progression opportunities in Ireland. However, most factors did not discriminate between intention to leave or stay. Factors that did predict intention to leave included dissatisfaction with one's work-life balance (odds ratio (OR) 2.51; 95% confidence interval (CI) 1.53-4.10; P < 0.001); feeling that the quality of training in Ireland was poor (OR 1.82; 95% CI 1.09-3.05; P = 0.002) and leaving for family or personal reasons (OR 1.85; 95% CI 1.08-3.17; P = 0.027). Qualitative findings illustrated the stress of doing postgraduate

Does Emigration Affects Wages? A Case Study on Romania

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Costin-Alexandru Ciupureanu

2014-11-01

Full Text Available The migration phenomenon in Romania is characterized by emigration; the number of Romanian migrants skyrocketed after the Romanian accession to the European Union in 2007. With the economic and financial crisis outlook and with the labour market liberalization across the whole European Union for the Romanian workers starting this year the number of Romanian migrants is expected to increase further. Against this background this paper analyses the effects of emigration on wages in Romania. It is found that emigration has a positive impact on wages in Romania.

[Pakistan: emigration in the Gulf and its effects on the home economy].

Science.gov (United States)

Imdad, N

1985-01-01

Pakistani emigration since the early 1970s has been primarily directed toward the oil-rich Gulf states. Over 2 million Pakistanis, 10% of the adult male workforce, now live outside their home country, 3/4 of them in the Gulf states. The emigration has shortterm advantages for Pakistan, which has a high unemployment rate and few other exports. 2 government bureaus and over 300 recruiting agencies encourage Pakistani emigration to the Gulf, and because of the foreign exchange earnings generated, such emigration has become an important concern of the government. Emigration has a long history in Pakistan as part of the migratory movements of the Indian subcontinent in general. Emigration in the 1960s was prompted by mechanization of agriculture and disturbances of traditional agrarian labor arrangements brought on by the Green Revolution. Concentrations of lands among the successful middle-sized producers led to a rural proletariat and exodus towards the cities, where possibilities of employment were scarce. Regions of declining income around the new capital of Islamabad were the 1st to take advantage of new employment opportunities in the Gulf states. Pakistani migration to the Gulf countries is temporary for individual workers, who stay an average of 3-6 years, but the effect is of chain migration as returning workers are replaced by other family members. Workers are not accompanied by family members and have almost no contact with the local Arab populations. They send most of their earnings to their families in Pakistan. 3/4 are under 30 years old, most are of rural origin, and the majority are from the northern provinces. Although 70% are married, only 4% of migrants, the most highly qualified, are accompanied by their families. About 41% are unskilled workers and 42.6% are semiskilled or skilled manual workers. In 1981, the average annual salary repatriated by a Pakistani working in the Gulf was $3000. The Pakistani government has not defined a migration policy

Estimating temporary emigration and breeding proportions using capture-recapture data with Pollock's robust design

Science.gov (United States)

Kendall, W.L.; Nichols, J.D.; Hines, J.E.

1997-01-01

Statistical inference for capture-recapture studies of open animal populations typically relies on the assumption that all emigration from the studied population is permanent. However, there are many instances in which this assumption is unlikely to be met. We define two general models for the process of temporary emigration, completely random and Markovian. We then consider effects of these two types of temporary emigration on Jolly-Seber (Seber 1982) estimators and on estimators arising from the full-likelihood approach of Kendall et al. (1995) to robust design data. Capture-recapture data arising from Pollock's (1982) robust design provide the basis for obtaining unbiased estimates of demographic parameters in the presence of temporary emigration and for estimating the probability of temporary emigration. We present a likelihood-based approach to dealing with temporary emigration that permits estimation under different models of temporary emigration and yields tests for completely random and Markovian emigration. In addition, we use the relationship between capture probability estimates based on closed and open models under completely random temporary emigration to derive three ad hoc estimators for the probability of temporary emigration, two of which should be especially useful in situations where capture probabilities are heterogeneous among individual animals. Ad hoc and full-likelihood estimators are illustrated for small mammal capture-recapture data sets. We believe that these models and estimators will be useful for testing hypotheses about the process of temporary emigration, for estimating demographic parameters in the presence of temporary emigration, and for estimating probabilities of temporary emigration. These latter estimates are frequently of ecological interest as indicators of animal movement and, in some sampling situations, as direct estimates of breeding probabilities and proportions.

Student Mobility or Emigration Flow? The Case of Students Commuting from Serbia to Hungary

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Zoltan Takac

2015-04-01

Full Text Available Student mobility between two European countries in transition, Hungary and Serbia, was considered for the period 2001-2010. The high motivation and number of Hungarian-speaking students emigrating/commuting to Hungary began in 1990, with the beginning of the Yugoslav Wars. In 2010, 1,385 Hungarian-speaking students (from Vojvodina, Serbia studied in Hungary and 3,152 in Serbia. Student mobility between Hungary and Serbia is highly concentrated and causes a very low returning rate of educated young elite (approximately 30%. For this reason, the future of the Hungarian minority has begun to be put into question in Serbia, in the Autonomous Province of Vojvodina, where their percentage within whole population is noticeably decreasing (1991: 16.9%, 2001: 14.3%. The research has been focused on answering the following questions: Are there integration conflicts in the autochthon minority within the state borders of Serbia? What can higher education offer to these students? Does the region offer enough to provide perspectives for young members of the elite? Will early student mobility end with continuous emigration? Empirical background: Interviews with young adult migrants from Serbia to Hungary; Location: Serbia. Objective: To examine the motives and willingness to emigrate among the Hungarian young adults/students from Vojvodina. Interview subjects: 18 university/college students or young adults with a diploma (from Vojvodina. It is important to note that only those young adults were interviewed who have returned to Serbia having finished their educational career or who are likely to come back later. Conclusions in brief: The Yugoslav Wars, worsening economic conditions, and low living standards have significantly influenced the willingness of the youth to migrate. The motives of migration among the Hungarian youth in Vojvodina are gaining professional experience, broadening knowledge, and improving language. Hungary is the first target country of

Materialism as a Social Value and Impetus for Intentions to Emigrate from Croatia

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Krešimir Peračković

2016-12-01

less universal - emigration. Croatia is a “traditional” emigration country, with unfavourable ratio of expatriate and resident population (it is estimated that the total number of emigrants equals the number of those who live in Croatia. If emigration had not been so intensive and did not last for more than a century, demographic analyses show that at least 6.22 million people would live in Croatia in 2001 or 40.1% more than today (Nejašmić, 2014. Taking into account a longer historical period, the Ottoman and other conquests (only the Ottoman threat lasted for four centuries, both World Wars and the Croatian War of Independence in the late 20th century, the geo-strategic position (the area of inter-civilizational conflicts or rally of the major political forces made Croatia a long-term scaffold, so forced emigration often meant saving lives (Rogić, 2000. In addition, scarce technical modernization and the nature of political associations in which Croatia had secondary political role completed the repertoire of motives for emigration: besides saving lives, people emigrated for economic, political and career reasons (Rogić and Čizmić, 2011. In addition to demographic approach, sociology of migration deals with the broader context and background social factors of migrations, including particular motives of migrants (e.g. Mesić, 2002; Mežnarić, 1991; Mesić et al., 1991; Katunarić, 1974. The literature dealing with this topic is not scarce, but there is a lack of research and analyses focused on a recent wave of emigration from Croatia in more detail, especially after joining the EU. However, it is known that higher earnings, primarily in Western Europe and the United States, are a permanent feature of voluntary and economic migration from Croatia or pull factor. For example, Mesić pointed out that the most agile part of labour force, including a substantial part of those already employed (mostly skilled or highly skilled workers emigrated by the end of the

QUALITY AND JOB SATISFACTION IN SPANISH EMIGRANTS IN EUROPEAN COUNTRIES

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Macarena Vallejo-Martín

2018-01-01

Full Text Available The current labor market is characterized by high unemployment rates, temporality, segmentation and precarious conditions. The numerical facet of employment is the focus of all concerns once more, casting aside any efforts regarding quality. In this context, emigration becomes a possible alternative once again, as it was in the past, and job satisfaction studies by social psychologists become a necessary focus of interest. This paper outlines the factors that can determine the two dimensions of job satisfaction, both intrinsic and extrinsic ones, and the psychosocial effects for this population that derive from them. With them we intend to offer some intervention guidelines in order to improve quality of life and well-being in this group.

Why do China-educated nurses emigrate? A qualitative exploration.

Science.gov (United States)

Zhou, Yunxian; Roscigno, Cecelia; Sun, Qiuhua

2016-01-01

Despite the fact that there are more and more Chinese nurses living and working in Australia, relatively little is known about the decisions to emigrate made by these nurses. To explore factors influencing China-educated nurses to emigrate to Australia. This was a secondary analysis of 46 semi-structured interviews with 28 China-educated nurses working in Australia. Conventional content analysis was used, and the results are presented thematically. The nurses emigrated for a wide variety of reasons: (a) personal factors (to improve English, to see more of the world and cultures, to seek novelty and adventure); (b) work-related factors (better work environment and more career choices); (c) social factors (better living environment and lifestyle); (d) cultural factors (positive perceptions in China of those who emigrate or have overseas experiences), and (e) economic factors (higher salaries and greater purchasing power). Confirming findings from similar studies, China-educated nurses' decisions to migrate are complex and not based solely on economic expectations. Personal and cultural factors play vital roles in nurses' migration decisions. Copyright © 2015 Elsevier Ltd. All rights reserved.

The role of emigration and migration in Swedish industrialization.

Science.gov (United States)

Karlstrom, U

1982-10-01

unaffected in 1880 but 1.5% higher in 1890. Emigration apparently had a positive effect on the standard of living in the rural areas, but possibly even larger rural to urban migration than occurred in the simulation would have happened in the absence of emigration. Rural to urban migration apparently had a significant growth creating effect. The reallocation of labor force to the more dynamic and high wage urban sector with its modern technology and higher rate of productivity change was of great importance to the economic performance of the national economy. More rural to urban migration has a temporary growth creating effect, but in the long run this effect disappears, because it also decreases the wage gap between rural and urban areas and consequently has a boomerang effect on itself.

Demographic Development of the Island of Brač and the Islanders’ Tendency to Emigrate

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Jelena Nakićen

2016-12-01

Full Text Available The paper analyses the basic demographic indicators of the Island of Brač and its settlements. Particular focus is on emigration from the island and its effect on demographic development of the island. The paper also presents the results of the survey conducted on the island in 2014. The aim of the survey was to investigate the level of satisfaction related to life on the island, and the respondents’ attitude toward emigration. Since the survey encompassed 151 permanent residents of the Island of Brač, the sample cannot be regarded as representative, so the survey results were not analysed separately, but rather incorporated in the demographic analysis. Throughout most of the 20th century, the Croatian insular area was characterised by intensive depopulation. Peak population on the islands was recorded in 1921, and it was followed by a long period of population decline, which lasted until 1991. However, the peak population on the Island of Brač was recorded in 1900, and it was also followed by a long period of depopulation, which ended in 1981. Official census data indicate that from 1981 until the present day Brač has recorded population increase, but that increase is actually fictitious (it was actually caused by “administrative immigration” – people increasingly registered their residence on the island in order to gain certain benefits regardless of their actual place of living or residence. Analysis of the population trends on the Island of Brač shows that in the period from 1857 to 1900, all the settlements on the island had population increase due to very favourable economic situation on the island brought by the vine-growing expansion. Economic prosperity of the island and high birth rates in the first phase of demographic transition resulted in rapid population growth. However, after the Wine Clause had been signed in 1891, and particularly after 1910, when phylloxera devastated the local vineyards, the insular economy

Emigration dynamics in South Asia, IOM / UNFPA workshop, 2-3 September 1996, IOM headquarters, Geneva, Switzerland.

Science.gov (United States)

Appleyard, R

1996-01-01

This paper describes the six research monographs that were presented at the Emigration Dynamic Workshops in South Asia in September 1996. Research reports were presented by Associate Professor Nasra Shah on an overview of emigration dynamics, Dr. Godfrey Gunatilleke on the role of networks and community structures in migration from Sri Lanka, Dr. Raisul Awal Mahmood on illegal migration from Bangladesh to Singapore, Kuala Lumpur, Bangkok, and Delhi due to desperate poverty, Dr. Farooq-i-Azam on high and low labor-sending migration districts in Pakistan, Dr. Mahendra K. Premi on the impact of internal Indian migration on international migration, and Dr. P.R. Gopinathan Nair on emigration from Kerala, India, to the Middle East. Representatives of South Asian governments discussed the implications of the research findings. Pakistan's representative urged cooperation and joint strategies among labor-sending countries. He cautioned that income and remittance estimates were unstable and unrealistic for inclusion in economic development plans. The Indian representative noted that, although Indian emigration is low, it is highly visible in the press. He agreed with the suggestion for greater cooperation between sending countries. The Bangladesh representative stated that the country needed to locate new markets for Bangladeshi emigrants, to guarantee the rights of emigrant workers, and to prevent trafficking in illegal migrant workers. Three major topics were discussed in the workshop session on the implementation of programs based on research findings. Workshop participants recommended updated information on migration trends, updated information on labor markets in receiving countries, formal and regular policy dialogue between sending countries, and promotion of continuing research by the International Organization on Migration.

Pakistani labour emigration: new destinations in Europe

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Nasra M. Shah

2005-01-01

Full Text Available In the first part of this paper a historical overview is made of Pakistani labour emigration to the countries of the Persian Gulf, and to Anglo-Saxon countries in general and to the United Kingdom in particular. In the second part of the paper the new European labourmarkets which Pakistani emigrants have been increasingly discovering is analyzed. In this sense, Spain has become one of the new destinations. The author goes on to point out the specific nature of this new situation and at the same time details some of the future implications for Spain.

Applying Organizational Commitment and Human Capital Theories to Emigration Research

Science.gov (United States)

Verkhohlyad, Olga; McLean, Gary N.

2012-01-01

Purpose: This study aims to bring some additional insight into the issue of emigration by establishing a relationship between emigration and psychic return of citizens to their human capital investment in the country. Design/methodology/approach: The article adopts a quantitative research strategy. It applies organizational commitment and human…

Political Changes in Croatia and the Croatian Emigrant Press in Chile

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Marina Perić

2005-06-01

Full Text Available The paper gives an overview of the Croatian emigrant press in Chile through five historical periods (before World War I, during World War I, between the two world wars, during World War II, after World War II. Parallels are drawn between political changes in Croatia and changes in the contents and themes of the emigrant press. One emigrant newspaper is analysed for each historical period, via the content analysis method, and front-page articles are taken as the units of analysis. Apart from the messages’ contents, their form is analysed, so as to assess opinions that the messages’ senders transmit to their receivers. Based on the analysis of the newspapers, the author concludes that changes in Croatia had an important influence on the emigrant press, which was especially visible in the period during World War I and World War II. In the period from World War I onwards, headings and themes in the emigrant press were used to propagate Yugoslavism and a sense of belonging to the Yugoslav nation and state. The identity of the emigrants changed under the influence of political changes in Croatia. Up to World War I they were mainly anti-Austrian oriented, and in the next four periods they accepted the state and the government of both the first and the second Yugoslavia, identifying themselves with Yugoslavia, and raising their descendents in a Yugoslav spirit.

The effects of varied densities on the growth and emigration of adult cutthroat trout and brook trout in fenced stream enclosures

Science.gov (United States)

Buys, D.J.; Hilderbrand, R.H.; Kershner, J.L.

2009-01-01

We evaluated the effects of various density treatments on adult fish growth and emigration rates between Bonneville cutthroat trout Oncorhynchus clarki utah and brook trout Salvelinus fontinalis in stream enclosures in Beaver Creek, Idaho, We used 3 density treatments (low, ambient, and high fish densities) to evaluate density-related effects and to ensure a response. Intraspecific ambient-density tests using cutthroat trout only were also performed. Results indicated an absence of cage effects in the stream enclosures and no differences in fish growth between ambient-density stream-enclosure fish and free-range fish. Brook trout outgrew and moved less than cutthroat trout in the stream enclosures, especially as density increased, In all 3 density treatments, brook trout gained more weight than cutthroat trout, with brook trout gaining weight in each density treatment and cutthroat trout losing weight at the highest density. At high densities, cutthroat trout attempted to emigrate more frequently than brook trout in sympatry and allopatry. We observed a negative correlation between growth and emigration for interspecific cutthroat trout, indicating a possible competitive response due to the presence of brook trout. We observed similar responses for weight and emigration in trials of allopatric cutthroat trout, indicating strong intraspecific effects as density increased. While cutthroat trout showed a response to experimental manipulation with brook trout at different densities, there has been long-term coexistence between these species in Beaver Creek, This system presents a unique opportunity to study the mechanisms that lead cutthroat trout to coexist with rather than be replaced by nonnative brook trout.

[To what extent is Mexican emigration to the United States a brain drain?].

Science.gov (United States)

Osborn, T N; Newton, J R

1979-01-01

The authors examine the problem of legal Mexican emigration to the United States, analyzing its effects on both countries. Characteristics of the Mexican emigrants are examined with respect to level of employment, salary, and employment opportunities. The total number of emigrants in professional and technical capacities is investigated in order to determine the likelihood of a brain drain from Mexico to the United States

Does the Attitude Toward Organ Donation Change as a Function of the Country Where People Emigrate? Study Between Uruguayan Emigrants to the United States and Spain.

Science.gov (United States)

Ríos, A; López-Navas, A I; Sánchez, Á; Ayala, M A; Garrido, G; Sebastián, M J; Martinez-Alarcón, L; Ramis, G; Hernández, A M; Ramírez, P; Parrilla, P

2018-03-01

The Uruguayan population is sensitized toward transplantation. However, it has not been studied how this awareness can change when emigrating to different countries. To analyze the attitude toward cadaveric organ donation and living organ donation between the Uruguayan population residing in Florida (United States) and the Uruguayan population residing in Spain. Adults born in Uruguay and residing in Florida and Spain were screened. The questionnaire "PCID-DTO Ríos" (donation of cadaveric organs) and "PCID-DVR Ríos" (living renal donation) were used. Subjects were randomly selected according to age and gender stratification. Support from Latin-American immigration associations in Spain and Florida was needed. The survey was anonymized and self-administered. Verbal consent was obtained to collaborate in the study. Because the emigrant population to Spain is far larger than the emigrant population to the United States, a 2:1 proportional sampling was performed (n = 132). Sixty-seven percent of residents in Spain were in favor of organ donation at the time of death compared with 50% among residents in Florida (P = .082), and 100% of residents in Spain were in favor of living renal donation compared with 50% of those living in Florida (P donation is more favorable among Uruguayan emigrants to Spain than emigrants to the United States, especially in related kidney donation. Copyright © 2017 Elsevier Inc. All rights reserved.

Emigration from Israel 1950-1981: a simulation study.

Science.gov (United States)

Jacobsen, C; Bronson, R

1988-01-01

"Using our mathematical model of a general theory of normative regulation, we have reproduced over 80% of the variance in the cumulative percentages of emigrants [from Israel], as well as the yearly percentages from 1950 to 1981. These results suggest that, except for a limited period following the 'Six-Day War' of 1967, no situation-specific explanations are needed to account for the trends in emigration from Israel, and the phenomenon can be adequately accounted for by the general theory of normative regulation in modern industrialized societies. Some practical conclusions to mitigate the process are drawn from these findings." excerpt

Eghterab’ in Iraqi Emigrants\\' Poetry: The Case of Ahmad Matar

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سید عدنان اشکوری

2009-12-01

Full Text Available ‘Eghterab’ in Iraqi Emigrants' Poetry: The Case of Ahmad Matar    Jafar Delshad *  Seyyed Adnan Eshkewaree **    Abstract  The word ‘eghterab’ in human sciences has different concepts which could be classified into three groups: 1 Westernization and tending to western culture or being alien with eastern authenticity 2 nostalgia and homesickness caused by being away from his/her motherhood land and hometown. Most of this group of poets are emigrants or are in exile and 3 having the sense of nostalgia but being in home country. It means that this group of poets have very high ideals which no one in their homeland can take and bare these ideals. The poet perceives that ideals which are essential for him/her are higher than the society in which he/she lives can grasp. This essay makes an attempt to study the various concepts of ‘eghterab’ by focusing on Ahmad Matar as a prominent poet with regard to the third concept and deal with the third concept of Eghterab from three points of view: political, social and spiritual. This article examines some samples of these three parts in Ahmad Matar's poetry.    Key words: nostalgia, poetry, emigration, Ahmad Matar, Iraq   * Assistant Professor, Department of Arabic Language and Literature, University of IsfahanE-mail: delshad@fgn.ui.ir  ** Assistant Professor, University for Teacher Training, E-mail: eshkewaree@yahoo.com.

High Emigration Propensity and Low Mortality on Transfer Drives Female-Biased Dispersal of Pyriglena leucoptera in Fragmented Landscapes.

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Marcelo Awade

Full Text Available Dispersal is a biological process performed in three stages: emigration, transfer and immigration. Intra-specific variation on dispersal behavior, such as sex-bias, is very common in nature, particularly in birds and mammals. However, dispersal is difficult to measure in the field and many hypotheses concerning the causes of sex-biased dispersal remain without empirical confirmation. An important limitation of most empirical studies is that inferences about sex-biased dispersal are based only on emigration proneness or immigration success data. Thus, we still do not know whether sex-biased immigration in fragmented landscapes occurs during emigration, transfer or in both stages. We conducted translocation and radiotracking experiments to assess i whether inter-patch dispersal movements of a rainforest bird (Pyriglena leucoptera is sex-biased and ii how dispersal stages and the perceptual range of the individuals are integrated to generate dispersal patterns. Our results showed that inter-patch dispersal is sex-biased at all stages for P. leucoptera, as females not only exhibit a higher emigration propensity but are subjected to a lower risk of predation when moving through the matrix. Moreover, our data support a perceptual range of 80 m and our results showed that dispersal success decreases considerably when inter-patch distances exceeds this perceptual range. In this case, birds have a higher probability of travelling over longer routes and, as a consequence, the risk of predation increases, specially for males. Overall, results supported that assuming dispersal as a single-stage process to describe dispersal behavior may be misleading. In this way, our study advanced our understanding of processes and patterns related to inter-patch dispersal of neotropical forest birds, shedding light on potential implications for population dynamics and for the management of fragmented landscapes.

[The use of personal sources for the study of emigration from Galicia: present state and perspectives].

Science.gov (United States)

Vazquez Gonzalez, A

1996-08-01

"Spanish sources for the study of emigration are sparse and fragmentary.... Mortgage documents for the payment of ocean transportation enable us to appreciate the spreading action of shipping agents; official listings of draft dodgers reveal that in general the River Plate was a favorite destination, rather than Cuba or Brazil. People from Galicia emigrated from rural origins to urban destinations in America; the analysis of place of birth of emigrants residing in A Coruna at the time of emigration show that there was also, in some cases, a first stage of rural-urban migration within Galicia. The general picture of emigration from Galicia is built [up] through the combination of the existing sources in Spain." (EXCERPT)

An emigration versus a globalization perspective of the Lebanese physician workforce: a qualitative study

Science.gov (United States)

2012-01-01

Background Lebanon is witnessing an increased emigration of physicians. The objective of this study was to understand the perceptions of Lebanese policymakers of this emigration, and elicit their proposals for future policies and strategies to deal with this emigration. Methods We conducted semi-structured individual interviews with the deans of Lebanon’s seven medical schools, the presidents of the two physicians professional associations, and governmental officials. We analyzed the results qualitatively. Results Participants differed in the assessment of the extent and gravity of emigration. Lebanon has a surplus of physicians, driven largely by the over-production of graduates by a growing number of medical schools. Participants cited advantages and disadvantages of the emigration on the personal, financial, medical education system, healthcare system, and national levels. Proposed strategies included limiting the number of students entering medical schools, creating job opportunities for graduating students, and implementing quality standards. Most participants acknowledged the globalization of the Lebanese physician workforce, including exchanges with the Gulf region, exchanges with developed countries, and the involvement of North American medical education institutions in the region. Conclusion Many Lebanese policy makers, particularly deans of medical schools, perceive the emigration of the physician workforce as an opportunity in the context of the globalization of the profession. PMID:22646478

An emigration versus a globalization perspective of the Lebanese physician workforce: a qualitative study.

Science.gov (United States)

Akl, Elie A; Maroun, Nancy; Rahbany, Aline; Hagopian, Amy

2012-05-30

Lebanon is witnessing an increased emigration of physicians. The objective of this study was to understand the perceptions of Lebanese policymakers of this emigration, and elicit their proposals for future policies and strategies to deal with this emigration. We conducted semi-structured individual interviews with the deans of Lebanon's seven medical schools, the presidents of the two physicians professional associations, and governmental officials. We analyzed the results qualitatively. Participants differed in the assessment of the extent and gravity of emigration. Lebanon has a surplus of physicians, driven largely by the over-production of graduates by a growing number of medical schools. Participants cited advantages and disadvantages of the emigration on the personal, financial, medical education system, healthcare system, and national levels. Proposed strategies included limiting the number of students entering medical schools, creating job opportunities for graduating students, and implementing quality standards. Most participants acknowledged the globalization of the Lebanese physician workforce, including exchanges with the Gulf region, exchanges with developed countries, and the involvement of North American medical education institutions in the region. Many Lebanese policy makers, particularly deans of medical schools, perceive the emigration of the physician workforce as an opportunity in the context of the globalization of the profession.

An emigration versus a globalization perspective of the Lebanese physician workforce: a qualitative study

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Akl Elie A

2012-05-01

Full Text Available Abstract Background Lebanon is witnessing an increased emigration of physicians. The objective of this study was to understand the perceptions of Lebanese policymakers of this emigration, and elicit their proposals for future policies and strategies to deal with this emigration. Methods We conducted semi-structured individual interviews with the deans of Lebanon’s seven medical schools, the presidents of the two physicians professional associations, and governmental officials. We analyzed the results qualitatively. Results Participants differed in the assessment of the extent and gravity of emigration. Lebanon has a surplus of physicians, driven largely by the over-production of graduates by a growing number of medical schools. Participants cited advantages and disadvantages of the emigration on the personal, financial, medical education system, healthcare system, and national levels. Proposed strategies included limiting the number of students entering medical schools, creating job opportunities for graduating students, and implementing quality standards. Most participants acknowledged the globalization of the Lebanese physician workforce, including exchanges with the Gulf region, exchanges with developed countries, and the involvement of North American medical education institutions in the region. Conclusion Many Lebanese policy makers, particularly deans of medical schools, perceive the emigration of the physician workforce as an opportunity in the context of the globalization of the profession.

Bloemfontein's Greek community: historical background, emigration ...

African Journals Online (AJOL)

Bloemfontein's Greek community: historical background, emigration and settlement, ca 1885 - ca 1985. ... South African Journal of Cultural History ... In this study a review is provided of the reasons why Greeks settled in Bloemfontein since about 1885, where these Greek immigrants came from, and how they travelled to ...

Physician Emigration from Sub-Saharan Africa to the United States: Analysis of the 2011 AMA Physician Masterfile

Science.gov (United States)

Tankwanchi, Akhenaten Benjamin Siankam; Özden, Çağlar; Vermund, Sten H.

2013-01-01

Background The large-scale emigration of physicians from sub-Saharan Africa (SSA) to high-income nations is a serious development concern. Our objective was to determine current emigration trends of SSA physicians found in the physician workforce of the United States. Methods and Findings We analyzed physician data from the World Health Organization (WHO) Global Health Workforce Statistics along with graduation and residency data from the 2011 American Medical Association Physician Masterfile (AMA-PM) on physicians trained or born in SSA countries who currently practice in the US. We estimated emigration proportions, year of US entry, years of practice before emigration, and length of time in the US. According to the 2011 AMA-PM, 10,819 physicians were born or trained in 28 SSA countries. Sixty-eight percent (n = 7,370) were SSA-trained, 20% (n = 2,126) were US-trained, and 12% (n = 1,323) were trained outside both SSA and the US. We estimated active physicians (age ≤70 years) to represent 96% (n = 10,377) of the total. Migration trends among SSA-trained physicians increased from 2002 to 2011 for all but one principal source country; the exception was South Africa whose physician migration to the US decreased by 8% (−156). The increase in last-decade migration was >50% in Nigeria (+1,113) and Ghana (+243), >100% in Ethiopia (+274), and >200% (+244) in Sudan. Liberia was the most affected by migration to the US with 77% (n = 175) of its estimated physicians in the 2011 AMA-PM. On average, SSA-trained physicians have been in the US for 18 years. They practiced for 6.5 years before US entry, and nearly half emigrated during the implementation years (1984–1999) of the structural adjustment programs. Conclusion Physician emigration from SSA to the US is increasing for most SSA source countries. Unless far-reaching policies are implemented by the US and SSA countries, the current emigration trends will persist, and the US will remain a leading

Emigrée Central European Jewish Women's Holocaust Life Writing

OpenAIRE

Vasvári, Louise O.

2009-01-01

In her paper "Emigrée Central European Jewish Women's Holocaust Life Writing," Louise O. Vasvári analyzes voices of women survivors from a gendered perspective in order to provide insights for both Holocaust studies and gender studies. Vasvári considers whether it can be claimed that there is a specifically female style of remembering and of testifying about these traumatic experiences. Vasvári's selection includes the writings of some two dozen Central European emigrée survivors, all native ...

Trajectories of emigrant quasi-citizenship: a comparative study of Mexico and Turkey.

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Yasar, Rusen

2017-01-01

In two of the busiest migration corridors of the twentieth century, namely Mexico-US and Turkey-Germany, migrants can today be dual citizens. However, the acceptance of dual citizenship did not occur automatically; instead, it followed a period of legal statuses short of full citizenship. This paper conceptualises such statuses as quasi-citizenship, a transitional equilibrium between the absence of plural citizenship and the existence of transnational migration. Focusing on sending states, the emergence of emigrant quasi-citizenship is thus explained, first, in terms of whether the reciprocal regimes of emigration and immigration states diverge on the acceptance of plural citizenship. Second, the stance towards plural citizenship is explained in terms of the experience with emigration. It is then shown that, in the case of Mexico, the legacy of undesired emigration weakened the incentives to adapt the territorial conception of citizenship to expatriates, hence creating quasi-citizens, and in the case of Turkey, the higher political relevance of expatriates, who could have the host country citizenship, reinforced the external dimension of the ethno-cultural conception of citizenship.

Private sector contributions and their effect on physician emigration in the developing world.

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Loh, Lawrence C; Ugarte-Gil, Cesar; Darko, Kwame

2013-03-01

The contribution made by the private sector to health care in a low- or middle-income country may affect levels of physician emigration from that country. The increasing importance of the private sector in health care in the developing world has resulted in newfound academic interest in that sector's influences on many aspects of national health systems. The growth in physician emigration from the developing world has led to several attempts to identify both the factors that cause physicians to emigrate and the effects of physician emigration on primary care and population health in the countries that the physicians leave. When the relevant data on the emerging economies of Ghana, India and Peru were investigated, it appeared that the proportion of physicians participating in private health-care delivery, the percentage of health-care costs financed publicly and the amount of private health-care financing per capita were each inversely related to the level of physician expatriation. It therefore appears that private health-care delivery and financing may decrease physician emigration. There is clearly a need for similar research in other low- and middle-income countries, and for studies to see if, at the country level, temporal trends in the contribution made to health care by the private sector can be related to the corresponding trends in physician emigration. The ways in which private health care may be associated with access problems for the poor and therefore reduced equity also merit further investigation. The results should be of interest to policy-makers who aim to improve health systems worldwide.

Characteristics of psychological violence (mobbing in terms of emigration

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Kovalchishina N.I.

2017-04-01

Full Text Available In the article the problem of psychological violence (mobbing in organizations, his psychological characteristics in emigration. Analyzes the types of mobbing, its negative influence on the personality, negative consequences which not only affect physical and psychological health, but also lead to physical diseases, and suicide. The author emphasizes that in conditions of exile (in Israel psychological violence is experienced more acutely and is characterized by a prolonged depressed state. One important reason for this situation is the decline of the former social status of the emigrant, being able to quickly inclusion in the new society, loss of important social ties, the need to adopt different social norms, sometimes contradicting previously established views. Against the background of such negative phenomena in humans appear aggression, desire to dominate at any cost to regain lost status. The problem of mobbing in the modern world is very important and requires a robust approach at the state level. That psychological safety is a condition for ensuring the formation and development of functional comfort, maintaining a high level of personal emotional security and social-psychological skills, optimization of reserve possibilities of the person in activities.

Emigration preferences and plans among medical students in Poland

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Krajewski-Siuda Krzysztof

2012-04-01

Full Text Available Abstract Background Migration and ethical recruitment of health care workers is receiving increased attention worldwide. Europe’s aging population is creating new opportunities for medical doctors for finding employment in other countries, particularly those of a better standard of living. Methods We conducted a survey among 1214 medical students in five out of eleven universities in Poland with medical schools in October 2008. A series of statistical tests was applied to analyse the characteristics of potential migrants. Projections were obtained using statistical analyses: descriptive, multifactorial logistic regression and other statistical methods . Results We can forecast that 26–36% of Polish medical students will emigrate over the next few years; 62% of respondents estimated the likelihood of emigration at 50%. Students in their penultimate year of study declared a stronger desire to migrate than those in the final year. At the same time, many students were optimistic about career opportunities in Poland. Also noted among students were: the decline in interest in leaving among final year students, their moderate elaboration of departure plans, and their generally optimistic views about the opportunities for professional development in Poland. Conclusions The majority of Polish students see the emigration as a serious alternative to the continuation of their professional training. This trend can pose a serious threat to the Polish health care system, however the observed decline of the interest in leaving among final year students, the moderate involvement in concrete departure plans and the optimistic views about the opportunities for professional development in Poland suggest that the actual scale of brain drain of young Polish doctors due to emigration will be more limited than previously feared.

Gone for good? An online survey of emigrant health professionals using Facebook as a recruitment tool.

Science.gov (United States)

McAleese, Sara; Clyne, Barbara; Matthews, Anne; Brugha, Ruairí; Humphries, Niamh

2016-06-30

Health professionals, particularly doctors, nurses and midwives, are in high demand worldwide. Therefore, it is important to assess the future plans and likelihood of return of emigrating health professionals. Nevertheless, health professionals are, by definition, a difficult population to track/survey. This exploratory study reports on the migration intentions of a sample of doctors, nurses and midwives who had emigrated from Ireland, a high-income country which has experienced particularly high outward and inward migration of health professionals since the year 2000. Health professionals who had emigrated from Ireland were identified via snowball sampling through Facebook and invited to complete a short online survey composed of closed and open response questions. A total of 388 health professionals (307 doctors, 73 nurses and 8 midwives) who had previously worked in Ireland completed the survey. While over half had originally intended to spend less than 5 years in their destination country at the time of emigration, these intentions changed over time, with the desire to remain abroad on a permanent basis increasing from 10 to 34 % of doctor respondents. Only a quarter of doctors and a half of nurses and midwives intended to return to practice in Ireland in the future. The longer health professionals remain abroad, the less likely they are to return to their home countries. Countries should focus on the implementation of retention strategies if the 'carousel' of brain drain is to be interrupted. This would allow source countries to benefit from their investments in training health professionals, rather than relying on international recruitment to meet health system staffing needs. Improved data collection systems are also needed to track the migratory patterns and changing intentions of health professionals. Meanwhile, social networking platforms offer alternative methods of filling this information gap.

POLITICAL LIFE OF THE COSSACKS IN EMIGRATION: TENDENCIES AND FEATURES

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Matsievsky German Olegovitch

2013-03-01

Full Text Available Purpose: To consider the main tendencies and features of political life of the Cossack emigration in the XX century. Methodology: Methodological basis of research are the standard principles of a historicism and the objectivity, assuming the concrete historical approach to the analysis of events in their dialectic development. Results: It is revealed that the Cossack emigration lost the political positions. Separation from sociocultural and geographical space of formation and development of traditional culture; foreign culture environment; refusal of the Cossack ideas of a collectivism and military brotherhood; destruction of the main institute of preservation and transfer of historical and cultural experience – a family; the constant feeling of «temporariness», despair and loss of belief in the future – all this generated the phenomenon called in cross-cultural psychology «cultural shock». Also crisis of ethnic and sociocultural consciousness and self-identification increased. Practical implications: Results of research can be interesting to the experts who are taking up the problems stories of the Cossacks in emigration.

FUNCTIONING OF THE SOVIET IDEOLOGEME IN THE EMIGRANT LITERATURE

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Мария Игоревна Шкредова

2013-04-01

Full Text Available In this article the author analyzes the features of functioning of the Soviet ideologeme in the literature of emigrants in details. Much attention is given to the term "ideologeme", its characteristics and features. Criteria of differentiation of the terms "Sovietism" and "ideologeme" are considered. There is the analysis of changes in perception of ideological expressions into space and time by examples of passages from the literature of the emigrant writers.The received results of research will spark the interest of the authors of dictionaries and teachers in development of programs for studying lexicon, stylistics and the culture of speech.DOI: http://dx.doi.org/10.12731/2218-7405-2013-2-40

Inference about density and temporary emigration in unmarked populations

Science.gov (United States)

Chandler, Richard B.; Royle, J. Andrew; King, David I.

2011-01-01

Few species are distributed uniformly in space, and populations of mobile organisms are rarely closed with respect to movement, yet many models of density rely upon these assumptions. We present a hierarchical model allowing inference about the density of unmarked populations subject to temporary emigration and imperfect detection. The model can be fit to data collected using a variety of standard survey methods such as repeated point counts in which removal sampling, double-observer sampling, or distance sampling is used during each count. Simulation studies demonstrated that parameter estimators are unbiased when temporary emigration is either "completely random" or is determined by the size and location of home ranges relative to survey points. We also applied the model to repeated removal sampling data collected on Chestnut-sided Warblers (Dendroica pensylvancia) in the White Mountain National Forest, USA. The density estimate from our model, 1.09 birds/ha, was similar to an estimate of 1.11 birds/ha produced by an intensive spot-mapping effort. Our model is also applicable when processes other than temporary emigration affect the probability of being available for detection, such as in studies using cue counts. Functions to implement the model have been added to the R package unmarked.

Russian women emigrées in psychology: informal Jewish networks.

Science.gov (United States)

Woodward, William R

2010-05-01

This paper uses archival sources and autobiographies to give a fuller account of the lives of three Russian women psychologists, each of whom voluntarily emigrated several years before the Third Reich. As such, their stories contribute to gender history, emigration history, and ethnic history. The characteristics of second-generation women in psychology seem to apply to this sample; they accepted applied or secondary positions in psychology or allied fields and came late to tenure-track positions. Some first-generation characteristics fit them also: choosing career over marriage, accepting the "family claim," and living "fractured lives." Emigrée history reveals that these women found careers in the United States that could not have happened in the smaller, more restricted higher education networks of Europe. Female friendships and family ties to the Old World sustained them. All struggled with professional networking and had varying success, depending heavily upon the patronage of sympathetic male psychologists. Ethnic history shows that none identified strongly with Judaism, yet all benefited from Jewish mentors and networks of patronage. Evidence of gendered or racial discrimination in hiring practices is sparse, though it surely existed.

Gulf migration study: Employment, wages and working conditions of Kerala emigrants in the United Arab Emirates

OpenAIRE

K.C. Zachariah; B.A. Prakash; S. Irudaya Rajan

2002-01-01

This is the fourth in a series of Working Papers published by the CDS on Kerala migration. Unlike the other three, this one is financed by the Kerala Government and the data were collected in UAE. The objectives of this Working Paper are to: document changes in the labour demand for different categories of emigrant workers, enumerate the emigration policies, examine employment and working conditions, wage levels and related problems of the Kerala emigrants, understand the education and traini...

Emigrating Beyond Earth Human Adaptation and Space Colonization

CERN Document Server

Smith, Cameron M

2012-01-01

For four million years humankind has been actively expanding geographically and in doing so has adapted to a wide variety of hostile environments. Now we are looking towards the ultimate adaptation - the colonization of space. Emigrating Beyond Earth illustrates that this is not a technocratic endeavor, but a natural continuation of human evolution; a journey not just for the engineer and rocket scientist, but for everyman. Based on the most current understanding of our universe, human adaptation and evolution, the authors explain why space colonization must be planned as an adaptation to, rather than the conquest of, space. Emigrating Beyond Earth argues that space colonization is an insurance policy for our species, and that it isn't about rockets and robots, it's about humans doing what we've been doing for four million years: finding new places and new ways to live. Applying a unique anthropological approach, the authors outline a framework for continued human space exploration and offer a glimpse of a po...

Family caregiving for older adults : gendered roles and caregiver burden in emigrant households of Kerala, India

NARCIS (Netherlands)

Ugargol, Allen Prabhaker; Bailey, Ajay

2018-01-01

The Indian state of Kerala leads the demographic transition and characteristically showcases emigration of predominantly male adult children, leaving behind parents, spouses and children. When men emigrate, gendered contexts burden women, especially spouses and daughters-in-law, with caregiving

Emigration dynamics in Sub-Saharan Africa.

Science.gov (United States)

Adepoju, A

1995-01-01

The introduction to this description of emigration dynamics in sub-Saharan Africa notes that the region is characterized by intensive migration caused by such factors as population growth, negative economic growth, ethnic conflict, and human rights abuses. The second section of the report discusses the fragmentary and incomplete nature of data on international migration in the region, especially data on conventional migration. Section 3 looks at demographic factors such as high population growth, illiteracy levels, HIV seroprevalence, and urbanization which lead to high unemployment and emigration. The fourth section considers the effects of the rapid expansion of education which is outstripping the absorptive capacity of the economies of many countries. Unemployment is a serious problem which is projected to become worse as increases in employment opportunities continue to lag behind increases in output. Sections five, six, and seven of the report describe relevant economic factors such as per capita income, income distribution, the economic resource base, and economic development; poverty; and the effects of economic adjustment programs, especially on employment opportunities and wages in the public and private sectors. The next section is devoted to sociocultural factors influencing migration both on the micro- and the macro-levels, including the influence of ethnicity and ethnic conflicts as well as the domination of leadership positions by members of minority groups. The political factors discussed in section 9 include women's status, repressive regimes, political instability which leads to underdevelopment, and the policies of the Organization of African Unity which broadened the definition of refugees and set inviolable borders of member states identical to those inherited upon independence. Section 10 outlines ecological factors contributing to migration, including the decline in acreage of arable land, soil deterioration, poor land management, and the

Observations on Forced Colony Emigration in Parachartergus fraternus (Hymenoptera: Vespidae: Epiponini: New Nest Site Marked with Sprayed Venom

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Sidnei Mateus

2011-01-01

Full Text Available Five cases of colony emigration induced by removal of nest envelope and combs and a single one by manipulation are described. The disturbance was followed by defensive patterns, buzz running, and adult dispersion. An odor trail created by abdomen dragging, probably depositing venom or Dufour's gland secretions, connected the original nest to the newly selected nesting place and guided the emigration. The substrate of the selected nesting place is intensely sprayed with venom prior to emigration, and this chemical cue marked the emigration end point. The colony moves to the new site in a diffuse cloud with no temporary clusters formed along the odor trail. At the original nest, scouts performed rapid gaster dragging and intense mouth contacts stimulating inactive individuals to depart. Males were unable to follow the swarm. Individual scouts switched between different behavioral tasks before and after colony emigration. Pulp collected from the old nest was reused at the new nest site.

22 CFR 99.2 - Reporting requirements for adoption cases involving children emigrating from the United States.

Science.gov (United States)

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Reporting requirements for adoption cases involving children emigrating from the United States. 99.2 Section 99.2 Foreign Relations DEPARTMENT OF... CHILDREN § 99.2 Reporting requirements for adoption cases involving children emigrating from the United...

Return emigration: analysis of the situation through life stories

Directory of Open Access Journals (Sweden)

M.R Pino Juste

2014-11-01

Full Text Available In the context of the importance presently acquired by return immigration in Spain, in this article a descriptive study around the returned emigrants over 65 years old in Galicia is presented.After a brief theoretical introduction on return migration,the research carried out is developed. In the first place, the methodology used in the investigation which allowed an approach to the point of view of the persons concerned is explained: the biographical method through the technique of life stories. In second term, the specific results of the research are presented. After out lining the profile of the returned emigrant, different categories relating to the migratory project in its different phases have been analyzed: fromits beginning —reasons for emigrating—, in their arrival to destiny—labour activity, adaptation, uprooting, etc.—, to the return—reasons for returning, problems of readjustment to the place of origin, etc.—

Dispersal Timing: Emigration of Insects Living in Patchy Environments.

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Milica Lakovic

Full Text Available Dispersal is a life-history trait affecting dynamics and persistence of populations; it evolves under various known selective pressures. Theoretical studies on dispersal typically assume 'natal dispersal', where individuals emigrate right after birth. But emigration may also occur during a later moment within a reproductive season ('breeding dispersal'. For example, some female butterflies first deposit eggs in their natal patch before migrating to other site(s to continue egg-laying there. How breeding compared to natal dispersal influences the evolution of dispersal has not been explored. To close this gap we used an individual-based simulation approach to analyze (i the evolution of timing of breeding dispersal in annual organisms, (ii its influence on dispersal (compared to natal dispersal. Furthermore, we tested (iii its performance in direct evolutionary contest with individuals following a natal dispersal strategy. Our results show that evolution should typically result in lower dispersal under breeding dispersal, especially when costs of dispersal are low and population size is small. By distributing offspring evenly across two patches, breeding dispersal allows reducing direct sibling competition in the next generation whereas natal dispersal can only reduce trans-generational kin competition by producing highly dispersive offspring in each generation. The added benefit of breeding dispersal is most prominent in patches with small population sizes. Finally, the evolutionary contests show that a breeding dispersal strategy would universally out-compete natal dispersal.

Death of a Nation? Debating the Great Transatlantic Emigration from Hungary, 1900-1914

Directory of Open Access Journals (Sweden)

István Kornél Vida

2015-01-01

Full Text Available The turn of the nineteenth and twentieth century was witness to an unprecedented wave of emigration from East Central Europe, with an estimated 1-1.5 million people leaving for the United States from the territory of Hungary. Such loss of population, mostly young males in their prime, shocked the nation and served as a subject for discussion in various forms and on multiple levels of discourse, from the newspaper reports through literary depictions, to scholarly publications and conferences. In this paper I examine significant monographs as well as conference volumes and proceedings, analyzing the major opinions and debates surrounding the causes and consequences of the Great Transatlantic Emigration. I discuss the most significant publications that appeared before the coming of the First World War, which put an end to mass emigration from Europe. These works in a sense represented the best that Hungarian migration studies had to offer for more than half a century, which makes them particulary worthy of scholarly attention.

Temporal and spatial patterns in the emigrations of the army ant Dorylus (Anomma) molestus in the montane forest of Mt Kenya

DEFF Research Database (Denmark)

Schöning, Caspar; Njagi, Washington M.; Franks, Nigel R.

2005-01-01

1. The emigration behaviour of the army ant Dorylus (Anomma) molestus was studied in the montane forest of Mt Kenya. This species forages by massive swarm raids (mean width 10.3 m ± 4.6 m SD), which are assumed to have a strong negative impact on the densities of prey populations. 2. For non......, the emigration direction is influenced by the location of the nearest neighbour. Colonies typically emigrate directly away from their nearest neighbour. 5. Local food depletion is likely to be the ultimate cause for emigrations in this species, because emigration distance is larger than foraging range...... and colonies move away from their nearest neighbour. A small percentage of emigrations may be triggered by pangolin attacks on nests. 6. Contrary to the prediction of a recently developed mathematical model for epigaeic swarm-raiding Dorylus (Anomma) species, D. (A.) molestus colonies do not engage...

MIGRATION AND INSTITUTIONAL CHANGE: THE CASES OF SOUTHERN MEXICAN STATES AND THEIR EMIGRANT COMMUNITIES IN THE UNITED STATES OF AMERICA

Directory of Open Access Journals (Sweden)

Sascha Krannich

2016-04-01

Full Text Available This paper illustrates institutional approaches of emigrant states toward emigrants abroad, and how these approaches can change over time. These can range from absolute exclusion and non-communication, over fractional collaboration in specific matters, to even permanent institutional inclusion, for instance, through representation of migrants in home parliaments or governments. The approach for institutional incorporation can not only take place on the national, but also on the subnational level. This is the case in Mexico, a federal state in which many member states conduct their own emigrant policy, partially in accord with federal efforts, and partially independently or contrary to the national attempt to address the emigrant community abroad. To highlight these different approaches, I would like to take a look at the Southern Mexican states of Oaxaca and Chiapas. Although these states show similar political and social structures, and hold relatively large emigrant populations in the United States of America, the institutional approaches toward their emigrants changed in two different ways: while the institutional opening in Oaxaca goes back to various initiatives by the Oaxacan migrant community in the United States of America, the policy change in Chiapas toward more inclusion of the emigrant community was actively promoted by the government of Chiapas.

Characterization of Structural and Pigmentary Colors in Common Emigrant (Catopsilia Pomona) Butterfly

International Nuclear Information System (INIS)

Ghate, Ekata; Kulkarni, G. R.; Bhoraskar, S. V.; Adhi, K. P.

2011-01-01

Study of structural colors in case of insects and butterflies is important for their biomimic and biophotonics applications. Structural color is the color which is produced by physical structures and their interaction with light while pigmentary color is produced by absorption of light by pigments. Common Emigrant butterfly is widely distributed in India. It is of moderate size with wing span of about 60-80 mm. The wings are broadly white with yellow or sulphur yellow coloration at places as well as few dark black patches. It belongs to family Pieridae. A study of structural color in case of Common Emigrant butterfly has been carried out in the present work. The characterization of wing color was performed using absorption spectroscopy. Scanning electron microscopic study of the wings of Common Emigrant butterfly showed that three different types of scales are present on the wing surface dorsally. Diffracting structures are present in certain parts of the surfaces of the various scales. Bead like structures are embedded in the intricate structures of the scales. Absorption spectra revealed that a strong absorption peak is seen in the UV-range. Crystalline structure of beads was confirmed by the X-ray diffraction analysis.

Psychoanalysis and the Emigration of Central and Eastern European Intellectuals.

Science.gov (United States)

Erős, Ferenc

2016-12-01

One of the most important phenomena in the intellectual history of the 20th century was the exodus of the European mind, the emigration of persons, ideas, techniques, and institutions in the vast areas of social, human, and natural sciences, as well as in literature and the visual arts. Among these exiled intellectuals, psychoanalysts formed a special group. This paper examines the major lines of the emigration of psychoanalysts from the countries of issue to the countries of reception. It focuses, in particular on Hungarian analysts and analytic candidates who left their country of birth in two waves, first after the failure of revolutions in 1918/19 for Berlin, and then after 1938, to escape the Nazis. The paper comments on the existential situation of émigré psychoanalysts in light of Hannah Arendt's writings on refugees.

The role played by recruitment agencies in the emigration of South ...

African Journals Online (AJOL)

The role played by recruitment agencies in the emigration of South African nurses. ... Many nurses who leave the Republic of South Africa might use recruitment agencies' assistance. These concerns raised by ... AJOL African Journals Online.

Majority children's evaluation of acculturation preferences of immigrant and emigrant peers

NARCIS (Netherlands)

Verkuijten, Maykel; Thijs, Jochem; Sierksma, Jellie; Leerstoel Verkuijten; Migration, Cultural Diversity and Ethnic Relation

2014-01-01

Using an experimental design, native majority group children (8-13 years, N = 842) evaluated acculturation strategies (assimilation, integration, and separation) adopted by immigrant and emigrant peers. There were medium to large effects of the perceived acculturation strategies on children's peer

Spanish youth is emigrating: A bibliometric approach to the media coverage.

Science.gov (United States)

Selva, Clara; Recordà, Aniol

2018-01-01

Recent years have witnessed the emigration of young Spanish people searching for labor opportunities. A decade after the beginning of the worldwide economic crisis in 2007, the rapid deterioration of living conditions and lack of opportunities for personal development combined with the breakdown of professional expectations have led thousands of young people to emigrate from Spain, creating the so-called youth exodus. The press has paid recurrent attention to this phenomenon, often using eye-catching headlines such as 'Brain Drain'. Given the regular interest of the media in this phenomenon, the objective of this research is to analyze the media coverage of the drain of Spanish talent capital, or the emigration of young Spanish people seeking a better future, to create a distributive map that defines the characteristics and trends of this coverage. The analyzed corpus comprises 346 articles from eight Spanish and eleven international newspapers. The articles were coded based on descriptive variables (i.e., author, publication year, newspaper and language) and categorical variables (i.e., section, method, approach to the phenomenon, assessment of the phenomenon and overview of the phenomenon). The results indicate a significant increase in press coverage over the past few years and reveal associations between assessment of the phenomenon and year and between assessment of the phenomenon and section. As a result of this research, new investigative lines are unveiled regarding the social construction of the phenomenon in the media and the identity and individual construction of the 'truncated careers' of young Spanish people.

Periodical Archaeology: Digital Production, Critical Discourse and Textual Communities in Emigre

NARCIS (Netherlands)

McVarish, Emily

2017-01-01

textabstractPublished in 1989, Emigre magazine’s eleventh issue, Ambition/Fear: Graphic Designers and the Macintosh Computer, contains vivid artifacts of a discipline’s first encounter with digital tools. From the aesthetics of bitmaps to the expressive interventions made possible by new access to

Emigration flows from North Africa to Europe.

Science.gov (United States)

Kassar, Hassène; Marzouk, Diaa; Anwar, Wagida A; Lakhoua, Chérifa; Hemminki, Kari; Khyatti, Meriem

2014-08-01

The region of North Africa (NA) represents a striking locality regarding migration with several migration patterns, namely emigration in the form of labour export to Europe and North America and, to a lesser extent, to the Arab Gulf area. The latter has increased enormously in the last decade because of the political instability in most of the NA countries. The aim of the present chapter was to explore the patterns of migration stocks and flows in NA countries, based on several websites, systematic review of journals, comparable data available by the United Nations and by the International Organization of Migration. The NA region has become an area of transit migration and labour migration. Emigrant flows from NA countries towards Europe and North America are increasing this decade more than towards the Arab Gulf countries after being replaced by Asian labour. The recent increase in the proportion of women among the migrant population is remarkable. Remittances sent by African migrants have become an important source of external finance for countries of origin. Transient and irregular migration to Egypt originates at the borders with Sudan, Palestine and Libya with destination to the Euro Mediterranean countries. In Tunisia and Morocco, irregular migrants originate from Sub-Saharan Africa to the northern borders. The NA countries serve as departure rather than destination countries, and migration flows to the Euro-Mediterranean countries through legal or illegal routes. © The Author 2014. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

Sex and drug risk behavior pre- and post-emigration among Latino migrant men in post-Hurricane Katrina New Orleans

Science.gov (United States)

Mills, Jennifer; Burton, Nicole; Schmidt, Norine; Salinas, Oscar; Hembling, John; Aran, Alberto; Shedlin, Michele; Kissinger, Patricia

2012-01-01

High rates of sex and drug risk behaviors have been documented among Latino migrant men in the U.S. Whether these behaviors were established in the migrants’ home countries or were adopted in the U.S. has not been described and has implications for prevention strategies. Quarterly surveys were conducted to gather information on selected sex and drug risk practices of Latino migrant men who arrived in New Orleans after Hurricane Katrina seeking work. Both kappa scores and McNemar’s tests were performed to determine if practice of these behaviors in home country was similar to practice post-emigration to the U.S. Female sex worker (FSW) patronage, same sex encounters (MSM), and crack cocaine use was more likely to occur post-rather than pre-emigration. Of those who ever engaged in these selected behaviors, most adopted the behavior in the U.S. (i.e. 75.8% of FSW patrons, 72.7% of MSM participants, and 85.7% of crack cocaine users), with the exception of binge drinking (26.8%). Men who were living with a family member were less likely to adopt FSW patronage OR=0.27, CI=0.10-0.76, whereas men who earned >$465 per week were more likely to adopt crack cocaine use OR=6.29 CI=1.29, 30.57. Interventions that facilitate the maintenance of family cohesion and provide strategies for financial management may be useful for reducing sex and drug risk among newly arrived migrants. PMID:22669638

THE EFFECTS OF INTERNATIONAL EMIGRATION ON THE ACAZÓNICA AND HATO DE LA HIGUERA AGROECOSYSTEMS IN VERACRUZ, MEXICO

Directory of Open Access Journals (Sweden)

Martha Elena Nava-Tablada

2010-07-01

Full Text Available Mexico has a tradition of migration to the United States. Nevertheless, Veracruz had not experienced a significant exodus of its population up until the nineteen nineties, when emigration from Veracruz began to increase rapidly, especially in the rural sector, thus affecting the region’s agroecosystems. Correspondingly, the main objective of this investigation was to analyze how international emigration has affected the agroecosystems of two rural communities in the state of Veracruz. Special attention was paid to factors such as family income, decision making, labor organization, agricultural diversity, technological management and the purpose of production. Information was gathered by direct observation and from interviews with key informants. A survey was conducted in 60 homes and six case studies were employed. Although there are differences between communities, regarding the type of migration (legal or illegal, generally, the following patterns were identified: 1 Agricultural activity is primarily subsidized by remittances sent by emigrants; 2 The departure of the head of the family leads to a change concerning who makes  the decisions;  woman normally occupy subordinate roles; 3 Migration results in an increase in the number of hired farm workers and a greater work load for those who remain in the community; 4 The departure of the work force tends to diminish agricultural diversity; 5 Remittances have a positive impact on technological management by the family production unit; 6 Illegal emigration favors subsistence farming, whereas legal emigration favors commercial production.

what place has an emigration past in an immigration present? italy ...

African Journals Online (AJOL)

enervated remnant in a land occupied by foreigners” (O'Brien 1953, quoted in Delaney .... to avoid remembering the country's long, often traumatic emigration history ... ethic. (Turco 2005:11). Whilst many Irish songs and poems lamented leaving their beloved land, Italian ... offended and insulted/or die in a mine. The Italian ...

Partitioning detectability components in populations subject to within-season temporary emigration using binomial mixture models.

Directory of Open Access Journals (Sweden)

Katherine M O'Donnell

Full Text Available Detectability of individual animals is highly variable and nearly always < 1; imperfect detection must be accounted for to reliably estimate population sizes and trends. Hierarchical models can simultaneously estimate abundance and effective detection probability, but there are several different mechanisms that cause variation in detectability. Neglecting temporary emigration can lead to biased population estimates because availability and conditional detection probability are confounded. In this study, we extend previous hierarchical binomial mixture models to account for multiple sources of variation in detectability. The state process of the hierarchical model describes ecological mechanisms that generate spatial and temporal patterns in abundance, while the observation model accounts for the imperfect nature of counting individuals due to temporary emigration and false absences. We illustrate our model's potential advantages, including the allowance of temporary emigration between sampling periods, with a case study of southern red-backed salamanders Plethodon serratus. We fit our model and a standard binomial mixture model to counts of terrestrial salamanders surveyed at 40 sites during 3-5 surveys each spring and fall 2010-2012. Our models generated similar parameter estimates to standard binomial mixture models. Aspect was the best predictor of salamander abundance in our case study; abundance increased as aspect became more northeasterly. Increased time-since-rainfall strongly decreased salamander surface activity (i.e. availability for sampling, while higher amounts of woody cover objects and rocks increased conditional detection probability (i.e. probability of capture, given an animal is exposed to sampling. By explicitly accounting for both components of detectability, we increased congruence between our statistical modeling and our ecological understanding of the system. We stress the importance of choosing survey locations and

Radiological Diagnoses in the Context of Emigration: Infectious diseases.

Science.gov (United States)

Stojkovic, Marija; Müller, Jan; Junghanss, Thomas; Weber, Tim Frederik

2018-02-01

 Globalization and emigration impact on the spectrum of diseases challenging health care systems. Medical practitioners have to particularly prepare for infectious diseases.  The database of a health care center specialized on tropical medicine was screened for patients with history of migration and one of the following diagnoses: Cystic echinococcosis, tuberculosis, schistosomiasis, visceral leishmaniosis, and neurocysticercosis. Representative casuistics were prepared from select case histories. Radiological pertinent knowledge was compiled based on literature search.  A small selection of frequently imported infectious diseases covers a considerable fraction of health care problems associated with migration. For cystic echinococcosis, schistosomiasis, and neurocysticercosis imaging is the most relevant diagnostic procedure defining also disease stages. Tuberculosis and visceral leishmaniosis are important differentials for malignant diseases.  Imaging plays a meaningful role in diagnosis, treatment stratification, and follow-up of imported infectious diseases. Radiological skills concerning these diseases are important for providing health care for patients in context of migration.   · Imaging plays a meaningful role in multidisciplinary care for imported infectious diseases.. · A small selection covers a considerable fraction of infectious diseases expected in context of migration.. · Stojkovic M, Müller J, Junghanss T et al. Radiological Diagnoses in the Context of Emigration: Infectious diseases. Fortschr Röntgenstr 2018; 190: 121 - 133. © Georg Thieme Verlag KG Stuttgart · New York.

[Emigration from Croatia to overseas and to European countries from the middle of the nineteenth century to 1981--an attempt at quantification].

Science.gov (United States)

Nejasmic, I

1990-12-01

"The paper analyses the quantitative aspect of emigration [from Croatia] to European and overseas countries in the period from the middle of the 19th century till 1981 (the time of the last census). Analysing various sources and studies, the author presents data on emigration form individual Croatian lands (Istria, civil Croatia, Dalmatia) in relation to individual emigration flows (to Europe, overseas) and periods (before World War I, the inter-war period, the post-war period), and at the same time he examines external migration as an effect of the two world wars." (SUMMARY IN ENG) excerpt

Gender Inequality and Emigration: Push factor or Selection process?

OpenAIRE

Baudassé, Thierry; Bazillier, Rémi

2012-01-01

Our objective in this research is to provide empirical evidence relating to the linkages between gender equality and international emigration. Two theoretical hypotheses can be made for the purpose of analyzing such linkages. The fi rst is that gender inequality in origin countries could be a push factor for women. The second one is that gender inequality may create a \\gender bias" in the selection of migrants within a household or a community. An improvement of gender equality would then inc...

[The Dutch emigration pattern around 1840 in the European perspective].

Science.gov (United States)

Stokvis Prd

1980-01-01

"In 1850 and 1860 the Netherlands ranked eighth among twelve North-Western European nations that contributed to the transatlantic migration. The Dutch emigration pattern reflecting the agrarian crisis of the 1840's resembled the one of Hanover and Westphalia, be it that like in Scandinavia the ecclesiastical situation played a more important part. Besides the motivating forces, conditions such as information, organization, public and official reactions, and transportation are reviewed." (SUMMARY IN ENG) excerpt

Species richness and occupancy estimation in communities subject to temporary emigration

Science.gov (United States)

Kery, M.; Royle, J. Andrew; Plattner, M.; Dorazio, R.M.

2009-01-01

Species richness is the most common biodiversity metric, although typically some species remain unobserved. Therefore, estimates of species richness and related quantities should account for imperfect detectability. Community dynamics can often be represented as superposition of species-specific phenologies (e. g., in taxa with well-defined flight [insects], activity [rodents], or vegetation periods [plants]). We develop a model for such predictably open communities wherein species richness is expressed as the sum over observed and unobserved species of estimated species-specific and site-specific occurrence indicators and where seasonal occurrence is modeled as a species-specific function of time. Our model is a multispecies extension of a multistate model with one unobservable state and represents a parsimonious way of dealing with a widespread form of 'temporary emigration.'' For illustration we use Swiss butterfly monitoring data collected under a robust design (RD); species were recorded on 13 transects during two secondary periods within data, where secondary samples are pooled. The latter model yielded unrealistically high estimates of total community size of 274 species. In contrast, estimates were similar under models applied to RD data with constant (122) or seasonally varying (126) detectability for each species, but the former was more parsimonious and therefore used for inference. Per transect, 6 44 (mean 21.1) species were detected. Species richness estimates averaged 29.3; therefore only 71% (range 32-92%) of all species present were ever detected. In any primary period, 0.4-5.6 species present were overlooked. Detectability varied by species and averaged 0.88 per primary sampling period. Our modeling framework is extremely flexible; extensions such as covariates for the occurrence or detectability of individual species are easy. It should be useful for communities with a predictable form of temporary emigration where rigorous estimation of community

Escape from Socialist Yugoslavia ‒ Illegal Emigration from Croatia from 1945 to the Beginning of the 1960s

Directory of Open Access Journals (Sweden)

Tatjana Šarić

2015-08-01

Full Text Available In the post-war socialist Yugoslavia political and/or economic situation has become unacceptable for part of the population. Since legal emigration from Croatia was not allowed, the number of illegal immigrants increased since the end of World War II. The article deals with this group of migrants using the comparative analysis of original archival materials and available literature in the period from 1945 to 1961 when the state began to gradually open the border. Mostly young people, under 25 years of age, immigrated illegally, mainly for economic reasons, and this was associated with a tradition of emigration, especially in the coastal region. In addition to the poor economic situation, people also emigrated for political reasons, then for adventure, to avoid serving in the Yugoslav People’s Army or to escape from the law for committing criminal offenses. They were fleeing by land or by sea, which was much more successful. Usually the first destinations of the immigrants were Italy, Austria and Germany, from where the majority of them moved to overseas countries. Most people fled the districts of Rijeka, Pula, Zagreb, Zadar, Šibenik and Split that existed at that time so that 74% of all illegal immigrants came from them. The runaways were mostly workers, followed by farmers, vocational school students, public servants, pupils and students, sailors and craftsmen. According to gender, there were many more men than women among the runaways, most of whom were unmarried. The authorities were trying to prevent the escape abroad by methods of controlling the border and prison sentences, but also by the attempts to ensure better living conditions in the affected areas. As these measures had not yielded the desired results, but also due to the beginning of the economic crisis and the appearance of unemployment, the authorities liberalized emigration procedures and opened the borders to immigrants which resulted in a new wave of economic emigration.

Majority Children's Evaluation of Acculturation Preferences of Immigrant and Emigrant Peers

Science.gov (United States)

Verkuyten, Maykel; Thijs, Jochem; Sierksma, Jellie

2014-01-01

Using an experimental design, native majority group children (8-13 years, N = 842) evaluated acculturation strategies (assimilation, integration, and separation) adopted by immigrant and emigrant peers. There were medium to large effects of the perceived acculturation strategies on children's peer evaluations. Overall, assimilation was valued…

Emigration from the South Caucasus: who goes abroad and what are the economic implications?

Czech Academy of Sciences Publication Activity Database

Dermendzhieva, Zvezda

2011-01-01

Roč. 23, č. 3 (2011), s. 377-398 ISSN 1463-1377 R&D Projects: GA MŠk LC542 Institutional research plan: CEZ:MSM0021620846 Keywords : emigration * economic development * household survey Subject RIV: AH - Economics Impact factor: 0.459, year: 2011

Partitioning detectability components in populations subject to within-season temporary emigration using binomial mixture models.

Science.gov (United States)

O'Donnell, Katherine M; Thompson, Frank R; Semlitsch, Raymond D

2015-01-01

Detectability of individual animals is highly variable and nearly always binomial mixture models to account for multiple sources of variation in detectability. The state process of the hierarchical model describes ecological mechanisms that generate spatial and temporal patterns in abundance, while the observation model accounts for the imperfect nature of counting individuals due to temporary emigration and false absences. We illustrate our model's potential advantages, including the allowance of temporary emigration between sampling periods, with a case study of southern red-backed salamanders Plethodon serratus. We fit our model and a standard binomial mixture model to counts of terrestrial salamanders surveyed at 40 sites during 3-5 surveys each spring and fall 2010-2012. Our models generated similar parameter estimates to standard binomial mixture models. Aspect was the best predictor of salamander abundance in our case study; abundance increased as aspect became more northeasterly. Increased time-since-rainfall strongly decreased salamander surface activity (i.e. availability for sampling), while higher amounts of woody cover objects and rocks increased conditional detection probability (i.e. probability of capture, given an animal is exposed to sampling). By explicitly accounting for both components of detectability, we increased congruence between our statistical modeling and our ecological understanding of the system. We stress the importance of choosing survey locations and protocols that maximize species availability and conditional detection probability to increase population parameter estimate reliability.

Antimasonian activity of Russian monarchical emigration of «first wave» (1917–1940

Directory of Open Access Journals (Sweden)

Ermakov V.A.

2018-03-01

Full Text Available summary: The work shows that in the modern domestic liberal historiography of Russian emigration, there is a tendency to conceal and hide political problems raised by Russian monarchists. And, on the contrary, in the works of representatives of the patriotic direction, a wide range of views of Russian monarchists, centered around the Masonic problem and the struggle against Bolshevism, are being explored. The system of estimations by Russian right-wing representatives of the «philosophical steamer» as «apologists of Freemasonry» and the bearers of the ideas of «Masonic democracy» and also as «reformers of Orthodoxy» was reconstructed. The specifics of the struggle of Russian patriotic circles of white emigration with the Russian Masonic lodges restored abroad are shown. The anti-Masonic activities of the Russian Church abroad are considered. As the highest achievement of anti-Masonic publicism is considered the religious and political philosophy of the history of Russian monarchists. The author believe that the main historiographic criterion for distinguishing the political activity of Russian emigration should be recognized as its pro-Masonic or anti-Masonic orientation. As a result of the research, the author come to the conclusion that the anti-Masonic activities of the Russian right largely objectively reflected the main contradiction of the Russian history of «post-October abroad» as the struggle of Russian patriotic monarchists and the Orthodox Church abroad with the Russophobic forces of the West, whose concentrated expression was Freemasonry.

[The effects of manpower emigration on income distribution and consumption models in the Egyptian economy].

Science.gov (United States)

Abdel Fadil, M

1985-01-01

; lower income groups are more likely to use a large proportion for support and to buy locally produced goods, while higher income groups tend to save more and to purchase a larger proportion of imported goods. 1 of the significant effects of remittances is to orient individual consumption toward luxury consumer goods, which in turn entails a progressive substitution of imported for local goods and a growing disparity between the consumption of those who succeed in migrating and those who don't. Remittances sent by low income emigrants for family support are the only mechanism with a stimulating effect on the demand for local goods of mediocre quality; all the other mechanisms stimulate the demand for high quality imported goods and services which have a negligible stimulating effect for the poorest segments of the population, rural or urban.

Where Did Central- and Eastern-European Emigrants Go and Why?

DEFF Research Database (Denmark)

Pytlikova, Mariola

Central European countries, and Romania and Bulgaria, while immigrants from the Baltic countries seem to rely much less on networks. Income gaps have a positive effect on migration flows, particularly from the Southeastern countries, while employment opportunities in destination countries are main...... an important role in international migration from those countries. The disaggregated results show that there are large differences between the CEE countries with respect to emigration patterns. The lagged stock of immigrants, which may reflect networks has a strong and positive effect for immigrants from...

The "New World is An Other World": Hungarian Transatlantic Emigrants' Handbooks and Guidebooks, 1903-1939

Directory of Open Access Journals (Sweden)

István Kornél Vida

2016-01-01

Full Text Available The process of migration includes the movement between relatively distant geographical locations as well as often facing considerable cultural differences between the sending and receiving countries. At the turn of the nineteenth and twentieth century, millions of emigrants from East Central Europe and Southern Europe sought their personal dreams in America, but had painfully little information at their disposal about the country, and were consequently in for a considerable “culture shock.” This paper examines the possible sources of information for soon-to-become transatlantic migrants from Europe in general, and from Hungary in particular. It analyzes the various types of “booster literature,” along with the people who had an interest in its publication, and offers a case study of handbooks and guidebooks written specifically for Hungarian emigrants to America during the first two decades of the twentieth century.

FEATURES OF THE USE OF INTERNATIONALISM IN THE LITERATURE OF THE EMIGRANT WRITERS IN THE AGE OF GLOBALIZATION

Directory of Open Access Journals (Sweden)

2013-02-01

Full Text Available In this article the features of the use of internationalism in the literature of emigrants are considered. The functioning of international lexicon is considered at the present stage of development in the age of globalization. In the article the terms "Sovietism" and "internationalism " are analyzed and differentiated. Characteristic features of these terms are considered. Special attention is given to internationalism of the Soviet era. There is the analysis of changes in the associations, stylistic nuance and emotional assessment by examples of the Soviet internationalism in the literature of emigrants in the age of globalization. The received results can be used in making of dictionary of Sovietism, development of the programs for lexicon and stylistics study.

[Development and application of a web-based expert system using artificial intelligence for management of mental health by Korean emigrants].

Science.gov (United States)

Bae, Jeongyee

2013-04-01

The purpose of this project was to develop an international web-based expert system using principals of artificial intelligence and user-centered design for management of mental health by Korean emigrants. Using this system, anyone can access the system via computer access to the web. Our design process utilized principles of user-centered design with 4 phases: needs assessment, analysis, design/development/testing, and application release. A survey was done with 3,235 Korean emigrants. Focus group interviews were also conducted. Survey and analysis results guided the design of the web-based expert system. With this system, anyone can check their mental health status by themselves using a personal computer. The system analyzes facts based on answers to automated questions, and suggests solutions accordingly. A history tracking mechanism enables monitoring and future analysis. In addition, this system will include intervention programs to promote mental health status. This system is interactive and accessible to anyone in the world. It is expected that this management system will contribute to Korean emigrants' mental health promotion and allow researchers and professionals to share information on mental health.

Use of olfactory cues by newly metamorphosed wood frogs (Lithobates sylvaticus) during emigration

Science.gov (United States)

Zydlewski, Joseph D.; Popescu, Viorel D.; Brodie, Bekka S.; Hunter, Malcom L.

2012-01-01

Juvenile amphibians are capable of long-distance upland movements, yet cues used for orientation during upland movements are poorly understood. We used newly metamorphosed Wood Frogs (Lithobates sylvaticus) to investigate: (1) the existence of innate (i.e., inherited) directionality, and (2) the use of olfactory cues, specifically forested wetland and natal pond cues during emigration. In a circular arena experiment, animals with assumed innate directionality did not orient in the expected direction (suggested by previous studies) when deprived of visual and olfactory cues. This suggests that juvenile Wood Frogs most likely rely on proximate cues for orientation. Animals reared in semi-natural conditions (1500 l cattle tanks) showed a strong avoidance of forested wetland cues in two different experimental settings, although they had not been previously exposed to such cues. This finding is contrary to known habitat use by adult Wood Frogs during summer. Juvenile Wood Frogs were indifferent to the chemical signature of natal pond (cattle tank) water. Our findings suggest that management strategies for forest amphibians should consider key habitat features that potentially influence the orientation of juveniles during emigration movements, as well as adult behavior.

Esmeralda Energy Company, Final Scientific Technical Report, January 2008. Emigrant Slimhole Drilling Project, DOE GRED III

Energy Technology Data Exchange (ETDEWEB)

Deymonaz, John [Fish Lake Green Power Co. (United States); Hulen, Jeffrey B. [Univ. of Utah, Salt Lake City, UT (United States). Energy and Geosciences Inst.; Nash, Gregory D. [Univ. of Utah, Salt Lake City, UT (United States). Energy and Geosciences Inst.; Schriener, Alex [Earth Systems Southwest (United States)

2008-01-22

The Emigrant Slimhole Drilling Project (ESDP) was a highly successful, phased resource evaluation program designed to evaluate the commercial geothermal potential of the eastern margin of the northern Fish Lake Valley pull-apart basin in west-central Nevada. The program involved three phases: (1) Resource evaluation; (2) Drilling and resource characterization; and (3) Resource testing and assessment. Efforts included detailed geologic mapping; 3-D modeling; compilation of a GIS database; and production of a conceptual geologic model followed by the successful drilling of the 2,938 foot deep 17-31 slimhole (core hole), which encountered commercial geothermal temperatures (327⁰ F) and exhibits an increasing, conductive, temperature gradient to total depth; completion of a short injection test; and compilation of a detailed geologic core log and revised geologic cross-sections. Results of the project greatly increased the understanding of the geologic model controlling the Emigrant geothermal resource. Information gained from the 17-31 core hole revealed the existence of commercial temperatures beneath the area in the Silver Peak Core Complex which is composed of formations that exhibit excellent reservoir characteristics. Knowledge gained from the ESDP may lead to the development of a new commercial geothermal field in Nevada. Completion of the 17-31 core hole also demonstrated the cost-effectiveness of deep core drilling as an exploration tool and the unequaled value of core in understanding the geology, mineralogy, evolutional history and structural aspects of a geothermal resource.

Apparent survival of the salamander Salamandra salamandra is low because of high migratory activity

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Schaub Michael

2007-09-01

Full Text Available Abstract Background Understanding the demographic processes underlying population dynamics is a central theme in ecology. Populations decline if losses from the population (i.e., mortality and emigration exceed gains (i.e., recruitment and immigration. Amphibians are thought to exhibit little movement even though local populations often fluctuate dramatically and are likely to go exinct if there is no rescue effect through immigration from nearby populations. Terrestrial salamanders are generally portrayed as amphibians with low migratory activity. Our study uses demographic analysis as a key to unravel whether emigration or mortality is the main cause of "losses" from the population. In particular, we use the analysis to challenge the common belief that terrestrial salamanders show low migratory activity. Results The mark-recapture analysis of adult salamanders showed that monthly survival was high (> 90% without a seasonal pattern. These estimates, however, translate into rather low rates of local annual survival of only ~40% and suggest that emigration was important. The estimated probability of emigration was 49%. Conclusion Our analysis shows that terrestrial salamanders exhibit more migratory activity than commonly thought. This may be due either because the spatial extent of salamander populations is underestimated or because there is a substantial exchange of individuals between populations. Our current results are in line with several other studies that suggest high migratory activity in amphibians. In particular, many amphibian populations may be characterized by high proportions of transients and/or floaters.

"I Fear the Consequences to Our Animals": Emigrants and Their Livestock on the Overland Trails

Science.gov (United States)

Ahmad, Diana L.

2012-01-01

The diaries, letters, and guidebooks written by the emigrants who crossed North America on the overland trails during the mid-nineteenth century reveal a new awareness of the animals that journeyed with them. Often written as advice to those who might follow them, the travelers worried about their animals in ways beyond what theologians and…

FEATURES OF THE USE OF INTERNATIONALISM IN THE LITERATURE OF THE EMIGRANT WRITERS IN THE AGE OF GLOBALIZATION

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Мария Игоревна Шкредова

2013-04-01

Full Text Available In this article the features of the use of internationalism in the literature of emigrants are considered. The functioning of international lexicon is considered at the present stage of development in the age of globalization. In the article the terms "Sovietism" and "internationalism " are analyzed and differentiated. Characteristic features of these terms are considered. Special attention is given to internationalism of the Soviet era. There is the analysis of changes in the associations, stylistic nuance and emotional assessment by examples of the Soviet internationalism in the literature of emigrants in the age of globalization.The received results can be used in making of dictionary of Sovietism, development of the programs for lexicon and stylistics study.DOI: http://dx.doi.org/10.12731/2218-7405-2013-2-41

Russian Expatriate Community in A.V. Antoshin’s Monograph “Russian Emigrants in Terms of “Cold War” (Middle 1940s – Middle 1960s”: Establishment, Political Activity, Relation with the USSR

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Artem I. Kuritsyn

2013-01-01

Full Text Available The review considers A.V. Antoshin’s monograph “Russian Emigrants in Terms of “Cold War” (Middle 1940s – Middle 1960s”. Special attention is attached to the problem, concerned with the second wave of emigration. The article analyses the process of Soviet citizens repatriation after the World War II, considers the issues, concerned with the political activities of Russian expatriate community, propaganda efforts of People’s Labor Union and other emigration organizations.

La migración de médicos en Venezuela The emigration of physicians in Venezuela

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Tulia Hernández

2011-08-01

Venezuelan health professionals to emigrate to other countries. METHODS: Exploratory study that applied a semistructured interview and survey, respectively, to a population consisting of four health professionals and 36 medical students. The interview data were analyzed by deductive and inductive categorization and the survey data by means of univariate and bivariate analysis. RESULTS: It was observed that 13.8% of the students generally intended to emigrate, with differences between the two study groups. It was found that work-related issues had a high motivating effect (16.6%, particularly the possibility of balancing work with personal life, better pay, access to continuing education, working in a better health system, and having the basic resources necessary for professional practice. It was determined that professional reasons had a moderate motivating effect (13.8%, whereas personal and contextual reasons had little influence (less than 3%. Although the interviews of physicians who had obtained their medical degree revealed clashes involving political and economic interests, only 5.5% of the students surveyed considered the political or economic situation a determinant in the emigration of professionals. CONCLUSIONS: It is recommended that the management and professional development of medical personnel be strengthened, reconciling their expectations with the legal framework and needs of the health system. A formal system for tracking the emigration of professionals and broadening the study of the causative factors at the national level should be set up, since better knowledge about the phenomena linked with emigration would help generate and support proposals to guarantee self-sufficiency with respect to human resources for health.

Russian Expatriate Community in A.V. Antoshin’s Monograph “Russian Emigrants in Terms of “Cold War” (Middle 1940s – Middle 1960s)”: Establishment, Political Activity, Relation with the USSR

OpenAIRE

Artem I. Kuritsyn

2013-01-01

The review considers A.V. Antoshin’s monograph “Russian Emigrants in Terms of “Cold War” (Middle 1940s – Middle 1960s)”. Special attention is attached to the problem, concerned with the second wave of emigration. The article analyses the process of Soviet citizens repatriation after the World War II, considers the issues, concerned with the political activities of Russian expatriate community, propaganda efforts of People’s Labor Union and other emigration organizations.

Gender, Power, and Emigration From Mexico.

Science.gov (United States)

Nobles, Jenna; McKelvey, Christopher

2015-10-01

The prevailing model of migration in developing countries conceives of a risk-diversifying household in which members act as a single entity when making migration decisions. Ethnographic studies challenge this model by documenting gender hierarchy in family decisions and arguing that, in many contexts, men and women have differing views on the value of migration. We assess these perspectives using longitudinal survey data from Mexico. We show that Mexican households are heterogeneous in terms of women's decision-making authority and control over resources, and this variation predicts the subsequent emigration of their male partners to the United States. We then use data from a policy experiment to demonstrate that an exogenous increase in a woman's control over household resources decreases the probability that her spouse migrates. Our findings support the presence of important gender differences in how migration is valued. They also suggest that women's role in these decisions is inadvertently underrepresented in studies of migrant families. Staying is also a migration decision, and it is more likely in homes in which women have greater authority. From a policy perspective, the results suggest that Mexican migration is influenced not only by increases in household resources but also by which members of the household control them.

The role of family networks and migration culture in the continuation of Moroccan emigration: a gender perspective

NARCIS (Netherlands)

Heering, L; van der Erf, R; van Wissen, L

About 1.5 million people of Moroccan origin live as legal migrants in the countries of the European Union. For several decades, emigration has affected various provinces of Morocco. In some regions, the process started more than 40 years ago; in others the migration experience is much more recent.

Stochastic differential equation model for linear growth birth and death processes with immigration and emigration

International Nuclear Information System (INIS)

Granita; Bahar, A.

2015-01-01

This paper discusses on linear birth and death with immigration and emigration (BIDE) process to stochastic differential equation (SDE) model. Forward Kolmogorov equation in continuous time Markov chain (CTMC) with a central-difference approximation was used to find Fokker-Planckequation corresponding to a diffusion process having the stochastic differential equation of BIDE process. The exact solution, mean and variance function of BIDE process was found

Stochastic differential equation model for linear growth birth and death processes with immigration and emigration

Energy Technology Data Exchange (ETDEWEB)

Granita, E-mail: granitafc@gmail.com [Dept. Mathematical Education, State Islamic University of Sultan Syarif Kasim Riau, 28293 Indonesia and Dept. of Mathematical Science, Universiti Teknologi Malaysia, 81310,Johor (Malaysia); Bahar, A. [Dept. of Mathematical Science, Universiti Teknologi Malaysia, 81310,Johor Malaysia and UTM Center for Industrial and Applied Mathematics (UTM-CIAM) (Malaysia)

2015-03-09

This paper discusses on linear birth and death with immigration and emigration (BIDE) process to stochastic differential equation (SDE) model. Forward Kolmogorov equation in continuous time Markov chain (CTMC) with a central-difference approximation was used to find Fokker-Planckequation corresponding to a diffusion process having the stochastic differential equation of BIDE process. The exact solution, mean and variance function of BIDE process was found.

Sõdadevaheline vene emigratsioon suures ilmas ja väikeses Eesti / Interwar Russian Emigration in the Larger World and "Little Estonia"

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Irina Belobrovtseva

2015-06-01

Full Text Available Teesid: Oktoobrirevolutsiooni järgne vene emigratsioon, mida teaduskirjanduses traditsiooniliselt nimeta takse esimeseks laineks, valgus mööda ilma laiali ning oli seninägematult arvukas, haarates kaasa miljoneid endise Tsaari-Venemaa elanikke. Sellele nähtusele on pühendatud tuhandeid humanitaartea duslikke, sotsioloogilisi, politoloogilisi jm uurimusi, mis kajastavad vene eksiilkultuuri eri tahke. Vene emigratsioon puudutas ka Eestit ning enamik käsitletud ilmingutest olid otseselt seotud siinse vene kogukonnaga, ent kohati väga erineva tähendusega. Käesoleva artikli eesmärk on lühidalt kirjeldada vene emigratsiooni sotsiaalset ja demograafilist struktuuri, selle keskusi, emigrantide rolli oma ja võõra kultuuri säilitamisel, põlvkondadevahelist aspekti, eelkõige kirjanduselus, ning haridusküsimusi. Lähemalt on käsitletud vene emigrantide rolli Eesti kultuuris muu maailma taustal.    SU M M A R Y   After the October Revolution a mass of emigrants, all citizens of the former Tsarist Russia dispersed in the world. In the scholarly literature this dispersal of upwards of a million people has come to be referred to as the first wave of Russian emigration. Thousands of scholarly articles from the humanities, sociology, political science and other disciplines have been devoted to various aspects of Russian exile culture: descriptions of exile cultural centres (including Paris, Berlin, Constantinople, Brazil, and the USA; various cultural phenomena (literature, film, theatre, fashion, journalism, art, etc.. As was true of the large part of Europe, the Russian emigration impacted Estonia, as it did across the rest of Europe; however, the fate of the Russian community in Estonia had strikingly original features. Some of these derived principally from Estonia’s position as a border state, as well as from the fact that even in the days of the Russian Empire, over 40000 Russians resided in Estonia. Theoretically, this should have

Disappointed and Disgruntled: A Study of the Return in the 1990s of Czech Emigrants from the Communist Era

Czech Academy of Sciences Publication Activity Database

Nešpor, Zdeněk

2002-01-01

Roč. 38, č. 6 (2002), s. 789-808 ISSN 0038-0288 Institutional research plan: CEZ:AV0Z7028912 Keywords : Czech history * 20th century * Czech emigration Subject RIV: AO - Sociology, Demography Impact factor: 0.113, year: 2002

'Insane emigrants' in transit: Psychiatric patients' files as a source for the history of return migration, c. 1910

NARCIS (Netherlands)

Blok, G.

2015-01-01

This article highlights a source that can contribute to the history of migration and mental health: the case records of Eastern European emigrants who tried to enter America at the beginning of the twentieth century, but were refused entrance because of their alleged insanity. Some of these

Motivating employees in small and medium business enterprises in the context of intense workforce emigration

OpenAIRE

Almonaitienė, Junona

2011-01-01

An assumption is made in the article that incomplete motivating of employees by neglecting non-material incentives may be important reasons of workforce emigration, in addition to economic factors. An investigation of the situation concerning the fulfilment of Herzberg’s two kinds of factors (hygiene and motivating) in six Lithuanian small and medium business enterprises was conducted in order to test the assumption. The results from 159 employees questionnaires showed that hygiene factors ar...

The Psychological Consequences of Pre-Emigration Trauma and Post-Migration Stress in Refugees and Immigrants from Africa.

Science.gov (United States)

Steel, Jennifer L; Dunlavy, Andrea C; Harding, Collette E; Theorell, Töres

2017-06-01

Over 50 million people have been displaced, some as a result of conflict, which exposure can lead to psychiatric sequelae. The aims of this study were to provide estimates of pre-emigration trauma, post-migration stress, and psychological sequelae of immigrants and refugees from predominantly Sub-Saharan Africa who immigrated to Sweden. We also examined the predictors of the psychiatric sequelae as well as acculturation within the host country. A total of 420 refugees and immigrants were enrolled using stratified quota sampling. A battery of questionnaires including the Harvard Trauma Questionnaire, Post-Migration Living Difficulties Scale, the Cultural Lifestyle Questionnaire; and the Hopkins Checklist were administered. Descriptive statistics, Chi square analyses, Pearson correlations, analysis of variance, and logistic and linear regression were performed to test the aims of the study. Eighty-nine percent of participants reported at least one traumatic experience prior to emigration. Forty-seven percent of refugees reported clinically significant PTSD and 20 % reported clinically significant depressive symptoms. Males reported a significantly greater number of traumatic events [F(1, 198) = 14.5, p discrimination, and healthcare subscales. Females reported a higher prevalence of depressive symptoms when compared to males [F(1, 419) = 3.9, p = 0.05]. Those with a shorter duration in Sweden reported higher rates of PTSD [F(63, 419) = 1.7, p gender, education, religion, PTSD and post-migration stress. Sixty-nine percent of the variance associated with PTSD included education, number of traumatic events, depressive symptoms and post-migration stress. Forty-seven percent of the variance for acculturation was accounted for by a model that included age, education, duration in Sweden, anxiety, depression, and post-migration stress. These predictors were also significant for employment status with the exception of depressive symptoms. Multidimensional

Emigration and Economic Crisis: Recent Evidence from Uruguay

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Adela Pellegrino

2005-01-01

Full Text Available Uruguay es uno de los países sudamericanos con una proporción significativa de su población viviendo en el exterior. Desde los años setenta, el país ha tenido una emigración neta. Aunque esta tendencia se debilitó a principios de los noventa, recobró fuerza con la llegada de una severa crisis económica en 1999. En este artículo se discuten las características de la migración reciente de uruguayos y se pone en evidencia la relación entre crisis económica y emigración. El volumen del flujo poblacional en 2002 es comparable con las olas de migración que tuvieron lugar en los setenta. Los emigrantes con educación universitaria están sobrerrepresentados en comparación con la población general. Existe una correlación entre el acceso a redes de emigrantes uruguayos en los países de destino y la probabilidad de que un hogar haya tenido un miembro que emigró en 2002.

Migration, Masculinity and the Fugitive State of Mind in the Irish Emigrant Footballer Autobiography: the Case of Paul McGrath

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Marcus Free

2010-03-01

Full Text Available The ‘confessional’ autobiography has become a popular variant of professional football autobiography in Britain. Co-written ‘autobiographies’ by prominent former emigrant Irish or Irish descended international footballers have featured prominently in this sub-genre.  Their ‘confessions’ of alcoholism, gambling, infidelity, irresponsibility towards partners or dependents, or underlying ontological insecurity might be seen as an insightful engagement with their lives as male footballers in Britain.  However, focusing on two autobiographies of Paul McGrath, and reading these ‘troubled’ accounts using psychoanalytic perspectives on sport, migration and masculinity, it is argued that they are contradictory texts which embody a peculiar variation on the emigrant “fugitive state of mind” (Davar, 1996, both approximating and deferring mature, reflexive engagement with the social and cultural construction of identity, allowing them to occupy a liminal but discontent imaginary space in which adolescent masculinity can be indefinitely extended.   The homosocial world of men’s professional football is a key factor in this.

The literature of Slovenian political emigrants in Argentina after the Second World War

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Marija Uršula Geršak

2014-12-01

Full Text Available After the Second World War many political emigrants escaped from Slovenia to Argentina, among them leaders and soldiers of the home guard (belogardisti, sympathizers of the fascist forces, opponents of communism and their families, who were persecuted by the Yugoslav socialist regime. Among them were many intellectuals and artists, typically of right-wing political conviction and of Christian faith. In Argentina, they founded a hermetic community that kept the Slovenian language and traditional values, and hoped that one day they could return. People in the former Yugoslavia knew nothing about them or their activities or indeed about events after the war from the point of view of the Other. This paper reviews the historical circumstances that led to the emigration, the organization of the émigré community and their cultural life in Argentina, their literature, mainly novels and their ensconcement in another time and space, which is the time and space of memory and an idealized homeland. They were culturally very active and wrote mostly in Slovenian. It was not until the second generation and after Slovenia‘s independence when they published several works in Spanish. Mostly they wrote historical novels, memoirs, dealing with unhealed wounds years after the Second World War, exile, life in refugee camps, post-war killings. Many of the works are ideologically laden, moralistic and idealizing life in Slovenia before the War. Due to their close community, literary works are often subject to some kind of ‚(self censorship‘. Nevertheless, after Slovenia‘s independence, albeit with a delay, some of their works, because of their aesthetic and cultural values have become part of the national literatary canon and school textbooks.

The French Emigrants and the Evolution of Frenchification in Spain

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Emilio Luis LARA LÓPEZ

2017-02-01

Full Text Available With the Spanish Bourbons, there was a gradual introduction of Gallic cultural forms that gave rise to Frenchification, or cultural afrancesamiento, which was supported by most of the enlightened elite. The continual upheavals of the French Revolution and of the War of the Pyrenees were to change Spanish life in several of its facets, due in particular to the French emigrants. These exiles –above all, the clergymen– instilled in the popular classes a counterrevolutionary feeling that the Spanish clergy was to turn into a resentment of the French with religious and xenophobic overtones. Such latent prejudices were to reappear in 1808, in part helping to explain the forceful anti-Napoleonic reaction. The afrancesados supported the new Napoleonic Monarchy for political reasons with the purpose of regenerating the country. French residents in Spain from long before had to endure the anger of their Spanish neighbours at the beginning of the war as well as live under the cloak of suspicion.

A little-known narrative of Ukrainian political emigration in Czechoslovakia: assessment of the revolutionary experience and idea of the liberation struggle

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L. V. Doiar

2017-07-01

Full Text Available This article is devoted to the revolutionary struggle of the Ukrainian people in order to build their own state. The exile stage of the liberation struggle has been investigated by the author. This stage happened after the defeat of the revolution. Its members, while in exile emigration, were trying to comprehend what happened, to rethink it, to assess achievements and to conceptualize the future of the Ukrainian liberation process. During the investigation, the materials of the Central State Archive of higher authorities and government of Ukraine, sources from private funds of М. Shapoval, M. Balash, М. Timchenko; the fund of Prague group of the Ukrainian Socialist Revolutionary Party; funds of the Committee on commemoration of M. Shapoval; Funds of Ukrainian Social Institute (Ukrainian Sociological Institute, Ukrainian Free University, Ukrainian Economic Academy, established by Ukrainian emigrants on the territory of First Czechoslovak Republic, have been used. The above-mentioned sources are mainly narrative. Due to their disorder and dispersion, they still are little known. Moreover, the factual weakness of the narrative is its personal attitude, documentary non-proven, and, hence, its possible uncertain nature. However, the author does not exclude the fact that small attention to the exciting content of the post-revolutionary exile epistolary is explained by the dual unacceptability of its content: the Soviet historiography was unable to study it because of its ideological censorship restrictions and prohibitions, and modern historiography does not want to focus on defamatory assessments and interpretations on the liberation struggle of 1917-1921, especially heard from emigrants. Thanks to some openness of the participants of the revolution, which were very sincere in their stories due to the pain of defeat and grief of their exile status, and although biased at the same time, we can get some knowledge about atypical verbal history, that

Emigration and development: the case of a Bangladeshi village.

Science.gov (United States)

Rahman, M M

2000-01-01

This article examines the developmental consequences of international labor migration in a Bangladeshi village. The data are from the Hoglakandi, a village 30 km southeast of Dhaka, capital of Bangladesh. A structured questionnaire with both open-ended and closed category questions was used among 50 Singapore returnees, supplemented with additional in-depth interviews. International labor migration has often been seen by many sending countries as a short cut development because of its role in unemployment relief, balance of payments relief, and capital formation of national level. The study argues that the causes and effects of emigration can better be understood only when the process is placed within its local context, since what may prove to be advantageous at the national level may prove to be detrimental to a household or community or vice-versa. It demonstrates how the contribution of labor migration is merely the transformation of labor into a structural component of the international political economy. The Hoglakandi experience reveals that labor migration does not fuel the local economy from an external pipeline of remittances and skill acquisition, rather it drains local resources that retard the development.

Determinants of the remitting behaviour of Romanian emigrants in an economic crisis context

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Zizi GOSCHIN

2012-12-01

Full Text Available The remittances of international migrants are particularly important for Romania as one of the top European emigration countries and an important remittance recipient country as well. Responding to the need to better understand the determinants of remittances, our paper examines the significance of selected economic, social and demographic factors that impact on the remittance behaviour of Romanian international migrants, as characterized by the propensity to remit and the amount remitted. The present work builds on a new database of 1514 Romanian migrants from 52 destination countries, resulting from our 2010 online survey. One of the main findings is the fact that the remittances are strongly affected by migrant’s income, return intention and presence of the spouse in the destination country.

Fatty-acid profiles of white muscle and liver in stream-maturing steelhead trout Oncorhynchus mykiss from early migration to kelt emigration

Science.gov (United States)

Penney, Zachary L.; Moffitt, Christine M.

2015-01-01

The profiles of specific fatty acids (FA) in white muscle and liver of fasting steelhead troutOncorhynchus mykiss were evaluated at three periods during their prespawning migration and at kelt emigration in the Snake–Columbia River of Washington, Oregon and Idaho, to improve the understanding of energy change. Twenty-seven FAs were identified; depletion of 10 of these was positively correlated in liver and white muscle of prespawning O. mykiss. To observe relative changes in FA content more accurately over sampling intervals, the lipid fraction of tissues was used to normalize the quantity of individual FA to an equivalent tissue wet mass. Saturated and monounsaturated FAs were depleted between upstream migration in September and kelt emigration in June, whereas polyunsaturated FAs were more conserved. Liver was depleted of FAs more rapidly than muscle. Three FAs were detected across all sampling intervals: 16:0, 18:1 and 22:6n3, which are probably structurally important to membranes. When structurally important FAs of O. mykiss are depleted to provide energy, physiological performance and survival may be affected.

Reemigrace českých západních emigrantů v 90. letech 20. století z hlediska ekonomické sociologie

Czech Academy of Sciences Publication Activity Database

Nešpor, Zdeněk

2005-01-01

Roč. 41, č. 1 (2005), s. 31-55 ISSN 0038-0288 R&D Projects: GA ČR(CZ) GA403/03/0339 Institutional research plan: CEZ:AV0Z70280505 Keywords : migration studies * Czech Republic * Re-emigration Subject RIV: AO - Sociology, Demography Impact factor: 0.113, year: 2005

[The migration crisis of the summer of 1994. Balance and perspectives of Cuban emigration flows: 1984-1996].

Science.gov (United States)

Rodriguez Chavez, E

1996-01-01

"The article argues that the rafters crisis of 1994 and the resulting migration agreements between the United States and Cuba in 1994 and 1995 were a radical turn in policies and migration flows between the two countries. The article also describes the general evolution of Cuban migration flows towards the U.S. from the 1984 bilateral agreement up to 1996. As a context, it describes the structural elements of recent Cuban emigration and the place Cubans occupy in the general immigration from Latin America and the Caribbean." (EXCERPT)

Mariama on the Move. Migration Capital and Second Generations in Spanish Youth Emigration

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Laia Narciso Pedro

2017-12-01

Full Text Available Media representations of Spanish young adults leading a new emigration wave towards Europe in the last years usually picture by default a homogeneous group that does not match with the real flow. This paper contributes to make visible the diverse composition of Spanish youth who migrate abroad in the context of the economic crisis and their specific strategies based on ethnographic fieldwork carried out in the area of Barcelona. The analysis focuses on the case study of Mariama, the daughter of a West African family who migrated to Europe, and her community and emancipation mobility. Her trajectory and experiences show how migration capital is built and used to produce the emergence of a ‘new’ mobility project, while she joins that share of young Spaniards who have been forced to build their future in other European countries.

Use of the robust design to estimate seasonal abundance and demographic parameters of a coastal bottlenose dolphin (Tursiops aduncus population.

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Holly C Smith

Full Text Available As delphinid populations become increasingly exposed to human activities we rely on our capacity to produce accurate abundance estimates upon which to base management decisions. This study applied mark-recapture methods following the Robust Design to estimate abundance, demographic parameters, and temporary emigration rates of an Indo-Pacific bottlenose dolphin (Tursiops aduncus population off Bunbury, Western Australia. Boat-based photo-identification surveys were conducted year-round over three consecutive years along pre-determined transect lines to create a consistent sampling effort throughout the study period and area. The best fitting capture-recapture model showed a population with a seasonal Markovian temporary emigration with time varying survival and capture probabilities. Abundance estimates were seasonally dependent with consistently lower numbers obtained during winter and higher during summer and autumn across the three-year study period. Specifically, abundance estimates for all adults and juveniles (combined varied from a low of 63 (95% CI 59 to 73 in winter of 2007 to a high of 139 (95% CI 134 to148 in autumn of 2009. Temporary emigration rates (γ' for animals absent in the previous period ranged from 0.34 to 0.97 (mean  =  0.54; ±SE 0.11 with a peak during spring. Temporary emigration rates for animals present during the previous period (γ'' were lower, ranging from 0.00 to 0.29, with a mean of 0.16 (± SE 0.04. This model yielded a mean apparent survival estimate for juveniles and adults (combined of 0.95 (± SE 0.02 and a capture probability from 0.07 to 0.51 with a mean of 0.30 (± SE 0.04. This study demonstrates the importance of incorporating temporary emigration to accurately estimate abundance of coastal delphinids. Temporary emigration rates were high in this study, despite the large area surveyed, indicating the challenges of sampling highly mobile animals which range over large spatial areas.

High population increase rates.

Science.gov (United States)

1991-09-01

In addition to its economic and ethnic difficulties, the USSR faces several pressing demographic problems, including high population increase rates in several of its constituent republics. It has now become clear that although the country's rigid centralized planning succeeded in covering the basic needs of people, it did not lead to welfare growth. Since the 1970s, the Soviet economy has remained sluggish, which as led to increase in the death and birth rates. Furthermore, the ideology that held that demography could be entirely controlled by the country's political and economic system is contradicted by current Soviet reality, which shows that religion and ethnicity also play a significant role in demographic dynamics. Currently, Soviet republics fall under 2 categories--areas with high or low natural population increase rates. Republics with low rates consist of Christian populations (Armenia, Moldavia, Georgia, Byelorussia, Russia, Lithuania, Estonia, Latvia, Ukraine), while republics with high rates are Muslim (Tadzhikistan, Uzbekistan, Turkmenistan, Kirgizia, Azerbaijan Kazakhstan). The later group has natural increase rates as high as 3.3%. Although the USSR as a whole is not considered a developing country, the later group of republics fit the description of the UNFPA's priority list. Another serious demographic issue facing the USSR is its extremely high rate of abortion. This is especially true in the republics of low birth rates, where up to 60% of all pregnancies are terminated by induced abortions. Up to 1/5 of the USSR's annual health care budget is spent on clinical abortions -- money which could be better spent on the production of contraceptives. Along with the recent political and economic changes, the USSR is now eager to deal with its demographic problems.

High Rate Digital Demodulator ASIC

Science.gov (United States)

Ghuman, Parminder; Sheikh, Salman; Koubek, Steve; Hoy, Scott; Gray, Andrew

1998-01-01

The architecture of High Rate (600 Mega-bits per second) Digital Demodulator (HRDD) ASIC capable of demodulating BPSK and QPSK modulated data is presented in this paper. The advantages of all-digital processing include increased flexibility and reliability with reduced reproduction costs. Conventional serial digital processing would require high processing rates necessitating a hardware implementation in other than CMOS technology such as Gallium Arsenide (GaAs) which has high cost and power requirements. It is more desirable to use CMOS technology with its lower power requirements and higher gate density. However, digital demodulation of high data rates in CMOS requires parallel algorithms to process the sampled data at a rate lower than the data rate. The parallel processing algorithms described here were developed jointly by NASA's Goddard Space Flight Center (GSFC) and the Jet Propulsion Laboratory (JPL). The resulting all-digital receiver has the capability to demodulate BPSK, QPSK, OQPSK, and DQPSK at data rates in excess of 300 Mega-bits per second (Mbps) per channel. This paper will provide an overview of the parallel architecture and features of the HRDR ASIC. In addition, this paper will provide an over-view of the implementation of the hardware architectures used to create flexibility over conventional high rate analog or hybrid receivers. This flexibility includes a wide range of data rates, modulation schemes, and operating environments. In conclusion it will be shown how this high rate digital demodulator can be used with an off-the-shelf A/D and a flexible analog front end, both of which are numerically computer controlled, to produce a very flexible, low cost high rate digital receiver.

Generation of Tumor Antigen-Specific iPSC-Derived Thymic Emigrants Using a 3D Thymic Culture System

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Raul Vizcardo

2018-03-01

Full Text Available Summary: Induced pluripotent stem cell (iPSC-derived T cells may provide future therapies for cancer patients, but those generated by current methods, such as the OP9/DLL1 system, have shown abnormalities that pose major barriers for clinical translation. Our data indicate that these iPSC-derived CD8 single-positive T cells are more like CD4+CD8+ double-positive T cells than mature naive T cells because they display phenotypic markers of developmental arrest and an innate-like phenotype after stimulation. We developed a 3D thymic culture system to avoid these aberrant developmental fates, generating a homogeneous subset of CD8αβ+ antigen-specific T cells, designated iPSC-derived thymic emigrants (iTEs. iTEs exhibit phenotypic and functional similarities to naive T cells both in vitro and in vivo, including the capacity for expansion, memory formation, and tumor suppression. These data illustrate the limitations of current methods and provide a tool to develop the next generation of iPSC-based antigen-specific immunotherapies. : A barrier for clinical application of iPSC-derived CD8 T cells using OP9/DLL1 is their abnormal biology. Vizcardo et al. show that a 3D thymic culture system enables the generation of a homogeneous antigen-specific T cell subset, named iTEs, which closely mimics naive T cells and exhibits potent anti-tumor activity. Keywords: thymopoiesis, T cell differentiation, iPSC differentiation, adoptive cell transfer, naïve T cell, recent rhymic emigrants, fetal thymus organ culture, immunotherapy, 3D culture, tumor antigen specific T cell

A personality theory of U.S. migration geography.

Science.gov (United States)

Stetzer, F C

1985-01-01

"Neoclassical models of migration fail to account adequately for individual differences in propensity to migrate, rates of emigration from states and cities, and the generally high rates of population circulation common in the United States. This article proposes that migration propensity is related to an individual's personality. Using the facts that personality traits are generationally regenerative, both through inheritance and culture, and that the United States was settled in a series of migration waves from east to west, this theory predicts a spatial structuring of emigration rates which closely correspond to actual rates for states and major cities." excerpt

Unemployment of the educated and emigration of post-secondary graduates from the LDCs.

Science.gov (United States)

Blomqvist, A G

1985-01-01

The author examines the emigration of educated individuals from developing countries and reviews selected approaches to the study of international human capital flows. Attention is then given to two policy issues: the financing of postsecondary education and an international brain drain tax. The following factors are identified as critical in their impact on educated worker migration: "(a) the rigidity or flexibility of the wage in the market for the services of educated labour; (b) the extent of government subsidy (explicit or implicit) of the cost of post-secondary education; (c) the extent of responsiveness of the investment in education to the private return on such investment or its being exogenously controlled by the government; and (d) the type of restrictions (if any) imposed by the receiving industrialized countries on the migration flows from the LDCs." Comments by M. Ali Khan on a previous article by Blomqvist on the subject are also included (pp. 655-6). excerpt

Migration Intentions and Illicit Substance Use among Youth in Central Mexico

Science.gov (United States)

Marsiglia, Flavio Francisco; Kulis, Stephen; Hoffman, Steven; Calderón-Tena, Carlos Orestes; Becerra, David; Alvarez, Diana

2011-01-01

This study explored intentions to emigrate and substance use among youth (ages 14–24) from a central Mexico state with high emigration rates. Questionnaires were completed in 2007 by 702 students attending a probability sample of alternative secondary schools serving remote or poor communities. Linear and logistic regression analyses indicated that stronger intentions to emigrate predicted greater access to drugs, drug offers, and use of illicit drugs (marijuana, cocaine, inhalants), but not alcohol or cigarettes. Results are related to the healthy migrant theory and its applicability to youth with limited educational opportunities. The study’s limitations are noted. PMID:21955065

Emigrant psychoanalysts in the USA and the FBI archives.

Science.gov (United States)

Goggin, James E; Goggin, Eileen Brockman; Hill, Mary

2004-01-01

Interest in the fate of the German psychoanalysts who had to flee Hitler's Germany and find refuge in a new nation, such as the United States, has increased. The "émigré research" shows that several themes recur: (1) the theme of "loss" of one's culture, homeland, language, and family; and (2) the ambivalent welcome these émigrés received in their new country. We describe the political-social-cultural context that existed in the United States during the 1930s, 1940s, and 1950s. Documentary evidence found in the FBI files of three émigré psychoanalysts, Clara Happel, Martin Grotjahn, and Otto Fenichel, are then presented in combination with other source material. This provides a provisional impression of how each of these three individuals experienced their emigration. As such, it gives us elements of a history. The FBI documents suggest that the American atmosphere of political insecurity and fear-based ethnocentric nationalism may have reinforced their old fears of National Socialism, and contributed to their inclination to inhibit or seal off parts of themselves and their personal histories in order to adapt to their new home and become Americanized. They abandoned the rich social, cultural, political tradition that was part of European psychoanalysis. Finally, we look at these elements of a history in order to ask a larger question about the appropriate balance between a liberal democratic government's right to protect itself from internal and external threats on the one hand, or crossover into the blatant invasion of civil rights and due process on the other.

Understanding High Rate Behavior Through Low Rate Analog

Science.gov (United States)

2014-04-28

challenges in high rate character- isation of polymers. The most important is that, owing to their low stress wavespeed, the structural response of...box’ tool, to provide supporting date for the rate dependent mechanical character- isation . Experiments were performed on a TA instruments Q800

High burn rate solid composite propellants

Science.gov (United States)

Manship, Timothy D.

High burn rate propellants help maintain high levels of thrust without requiring complex, high surface area grain geometries. Utilizing high burn rate propellants allows for simplified grain geometries that not only make production of the grains easier, but the simplified grains tend to have better mechanical strength, which is important in missiles undergoing high-g accelerations. Additionally, high burn rate propellants allow for a higher volumetric loading which reduces the overall missile's size and weight. The purpose of this study is to present methods of achieving a high burn rate propellant and to develop a composite propellant formulation that burns at 1.5 inches per second at 1000 psia. In this study, several means of achieving a high burn rate propellant were presented. In addition, several candidate approaches were evaluated using the Kepner-Tregoe method with hydroxyl terminated polybutadiene (HTPB)-based propellants using burn rate modifiers and dicyclopentadiene (DCPD)-based propellants being selected for further evaluation. Propellants with varying levels of nano-aluminum, nano-iron oxide, FeBTA, and overall solids loading were produced using the HTPB binder and evaluated in order to determine the effect the various ingredients have on the burn rate and to find a formulation that provides the burn rate desired. Experiments were conducted to compare the burn rates of propellants using the binders HTPB and DCPD. The DCPD formulation matched that of the baseline HTPB mix. Finally, GAP-plasticized DCPD gumstock dogbones were attempted to be made for mechanical evaluation. Results from the study show that nano-additives have a substantial effect on propellant burn rate with nano-iron oxide having the largest influence. Of the formulations tested, the highest burn rate was a 84% solids loading mix using nano-aluminum nano-iron oxide, and ammonium perchlorate in a 3:1(20 micron: 200 micron) ratio which achieved a burn rate of 1.2 inches per second at 1000

INTERNATIONAL MIGRATION AND LABOUR MARKET IMPACTS

Directory of Open Access Journals (Sweden)

Liana SON

2012-10-01

Full Text Available The research aims to identify and analyse the impact of labour emigration on labour markets within the European Union. The analysis is based on developing double-log macroeconometric models that combine cross-section and time series in a panel structure, by using a set of indicators specific for the emigration process and labour market, as main explanatory variables. The results show that an intense emigration process has extremely negative effects on the size and structure of the labour force, generating its significant reduction, especially regarding the highly skilled labour. At the same time, we identified a relaxation of the labour market pressures generated by high unemployment, through a downsize of this rate and a slight increase in employment, mainly due to a general improvement of the local employment opportunities.

A Closer Look at the Junior Doctor Crisis in the United Kingdom's National Health Services: Is Emigration Justifiable?

Science.gov (United States)

Teo, Wendy Zi Wei

2018-07-01

This article attempts to tackle the ethically and morally troubling issue of emigration of physicians from the United Kingdom, and whether it can be justified. Unlike most research that has already been undertaken in this field, which looks at migration from developing countries to developed countries, this article takes an in-depth look at the migration of physicians between developed countries, in particular from the United Kingdom (UK) to other developed countries such as Canada, Australia, New Zealand, and the United States (US). This examination was written in response to a current and critical crisis in the National Health Service (NHS), where impending contract changes may bring about a potential exodus of junior doctors.

Response of insect relative growth rate to temperature and host-plant phenology: estimation and validation from field data.

Directory of Open Access Journals (Sweden)

Mamadou Ciss

Full Text Available Between 1975 to 2011, aphid Relative Growth Rates (RGR were modelled as a function of mean outdoor temperature and host plant phenology. The model was applied to the grain aphid Sitobion avenae using data on aphid counts in winter wheat at two different climate regions in France (oceanic climate, Rennes (western France; continental climate, Paris. Mean observed aphid RGR was higher in Paris compared to the Rennes region. RGR increased with mean temperature, which is explained by aphid reproduction, growth and development being dependent on ambient temperature. From the stem extension to the heading stage in wheat, there was either a plateau in RGR values (Rennes or an increase with a maximum at heading (Paris due to high intrinsic rates of increase in aphids and also to aphid immigration. From the wheat flowering to the ripening stage, RGR decreased in both regions due to the low intrinsic rate of increase in aphids and high emigration rate linked to reduced nutrient quality in maturing wheat. The model validation process showed that the fitted models have more predictive power in the Paris region than in the Rennes region.

Spanish Americanists, Diplomats and Emigrant Leaders in the Mexico of Centenario: the «Intellectual Embassy» as a Model of Pan-Hispanist Action (1909-1910

Directory of Open Access Journals (Sweden)

Gustavo H. Prado

2016-12-01

Full Text Available During the period of Centennial Celebrations of Latin American Independence, Spanish intellectuals of great reputation organized a persistent panhispanist campaign in Hispanic America. This paper analyzes the way in which americanists, diplomats and Spanish emigration leaders made common caused with, to promote their ideas, during the previous years to Porfiriato in Mexico. The concept of intellectual embassy will be used here to analyze their strategies.

High-Rate Strong-Signal Quantum Cryptography

Science.gov (United States)

Yuen, Horace P.

1996-01-01

Several quantum cryptosystems utilizing different kinds of nonclassical lights, which can accommodate high intensity fields and high data rate, are described. However, they are all sensitive to loss and both the high rate and the strong-signal character rapidly disappear. A squeezed light homodyne detection scheme is proposed which, with present-day technology, leads to more than two orders of magnitude data rate improvement over other current experimental systems for moderate loss.

FEMALE EMIGRATION. FROM RURAL ROMANIA TO THE ADRIATIC COAST: WOMEN ON THEIR JOURNEY BETWEEN OPPORTUNITY AND SOCIAL VULNERABILITY. “THE ITALIAN SYNDROME”

Directory of Open Access Journals (Sweden)

D. BURTINI

2015-10-01

Full Text Available Female Emigration. From Rural Romania to the Adriatic Coast: Women on Their Journey between Opportunity and Social Vulnerability. “The Italian Syndrome”. The twenty-first century can be called the “age of migration”, in fact since the de-colonization and markedly since the eighties migration affects the entire planet, qualifying as a global phenomenon. Comparing it with it in the past today prevails new elements and in fact, in addition to a geographical change of the phenomenon, it has turned its composition, showing a growing feminization.

The financial cost of doctors emigrating from sub-Saharan Africa: human capital analysis.

Science.gov (United States)

Mills, Edward J; Kanters, Steve; Hagopian, Amy; Bansback, Nick; Nachega, Jean; Alberton, Mark; Au-Yeung, Christopher G; Mtambo, Andy; Bourgeault, Ivy L; Luboga, Samuel; Hogg, Robert S; Ford, Nathan

2011-11-23

To estimate the lost investment of domestically educated doctors migrating from sub-Saharan African countries to Australia, Canada, the United Kingdom, and the United States. Human capital cost analysis using publicly accessible data. Sub-Saharan African countries. Nine sub-Saharan African countries with an HIV prevalence of 5% or greater or with more than one million people with HIV/AIDS and with at least one medical school (Ethiopia, Kenya, Malawi, Nigeria, South Africa, Tanzania, Uganda, Zambia, and Zimbabwe), and data available on the number of doctors practising in destination countries. The financial cost of educating a doctor (through primary, secondary, and medical school), assuming that migration occurred after graduation, using current country specific interest rates for savings converted to US dollars; cost according to the number of source country doctors currently working in the destination countries; and savings to destination countries of receiving trained doctors. In the nine source countries the estimated government subsidised cost of a doctor's education ranged from $21,000 (£13,000; €15,000) in Uganda to $58,700 in South Africa. The overall estimated loss of returns from investment for all doctors currently working in the destination countries was $2.17bn (95% confidence interval 2.13bn to 2.21bn), with costs for each country ranging from $2.16m (1.55m to 2.78m) for Malawi to $1.41bn (1.38bn to 1.44bn) for South Africa. The ratio of the estimated compounded lost investment over gross domestic product showed that Zimbabwe and South Africa had the largest losses. The benefit to destination countries of recruiting trained doctors was largest for the United Kingdom ($2.7bn) and United States ($846m). Among sub-Saharan African countries most affected by HIV/AIDS, lost investment from the emigration of doctors is considerable. Destination countries should consider investing in measurable training for source countries and strengthening of their

Articles

African Journals Online (AJOL)

2011-09-01

Sep 1, 2011 ... that an exchange of information can occur at a colony, ... events, low adult survival rates and high emigration rates, and these sinks are therefore prone to ..... Eurasian griffons Gyps fulvus in the island of Crete, Greece. Wildlife ...

BRAIN DRAIN IN THE GLOBALIZATION ERA: THE CASE OF ROMANIA

Directory of Open Access Journals (Sweden)

MARIANA BĂLAN

2017-06-01

Full Text Available Migration is an old phenomenon in the history of humankind. However, the magnitude, complexity, and structure of migration flows in the global era are all unprecedented. According to the United Nations Report “Trends in International Migrant Stock: the 2015 Revision” at world level 244 million international migrants were recorded in 2015. With the increase in the number of migrants, the emigration of ‘high-skilled’ individuals is also growing. OECD and United Nation Statistics show that in the last decade the number of migrants with tertiary education increased by about 70%. Brain drain is also a well-known phenomenon. Highly educated individuals and scientists have travelled the world in all centuries in search of better study and research, and working conditions, and of new opportunities. Nowadays, in the era of globalisation and, implicitly, of swifter development of international markets, the emigration rate of high-skilled experts exceeds the total emigration rate, which shows the selectiveness of migration at educational level. The paper presents a brief analysis of the interdependencies between migration and globalisation and of the effects of globalisation on the migration of high-skilled individuals. The trends, structure, and volume of high-skilled labour force from Romania are analysed along with the effects generated by them.

The Tec kinase ITK regulates thymic expansion, emigration, and maturation of γδ NKT cells.

Science.gov (United States)

Yin, Catherine C; Cho, Ok Hyun; Sylvia, Katelyn E; Narayan, Kavitha; Prince, Amanda L; Evans, John W; Kang, Joonsoo; Berg, Leslie J

2013-03-15

The Tec family tyrosine kinase, Itk, regulates signaling downstream of the TCR. The absence of Itk in CD4(+) T cells results in impaired Th2 responses along with defects in maturation, cytokine production, and survival of iNKT cells. Paradoxically, Itk(-/-) mice have spontaneously elevated serum IgE levels, resulting from an expansion of the Vγ1.1(+)Vδ6.3(+) subset of γδ T cells, known as γδ NKT cells. Comparisons between γδ NKT cells and αβ iNKT cells showed convergence in the pattern of cell surface marker expression, cytokine profiles, and gene expression, suggesting that these two subsets of NKT cells undergo similar differentiation programs. Hepatic γδ NKT cells have an invariant TCR and are derived predominantly from fetal progenitors that expand in the thymus during the first weeks of life. The adult thymus contains these invariant γδ NKT cells plus a heterogeneous population of Vγ1.1(+)Vδ6.3(+) T cells with diverse CDR3 sequences. This latter population, normally excluded from the liver, escapes the thymus and homes to the liver when Itk is absent. In addition, Itk(-/-) γδ NKT cells persistently express high levels of Zbtb16 (PLZF) and Il4, genes that are normally downregulated in the most mature subsets of NKT cells. These data indicate that Itk signaling is required to prevent the expansion of γδ NKT cells in the adult thymus, to block their emigration, and to promote terminal NKT cell maturation.

DEVELOPMENT OF MIGRATION POTENTIAL IN HUNGARY FROM 2000 UNTIL TODAY

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Margit Csipkés

2018-03-01

Full Text Available Hearing the words “international migration”, two things might come to our mind. One of them is the emigration process and the other is the wave of refugees. In our study, we examined the changes of the number of employees emigrating from Hungary from 2000 until today. Nowadays, the examination of the migration potential is an important topic in Hungary, since the rate of Hungarian emigrants started to grow after 2006 and the rate of growth became even faster after 2010. The reason of the acceleration was the opening of the Austrian and German labour market. The actuality of the topic is based on the fact that international emigration merges the labour market’s processes, influences the given country’s employment level, moreover it has an influencing role on the rate of wages. Emigration from a given state has several reasons: natural disasters, war, marginalization, economic reasons, etc. In our study, we examine emigration caused by economic reasons. We have to take into consideration that measuring emigration processes is a difficult task, due to the lack of data. The reason of the deficiency is that those who leave the country, often forget to report their leaving. From 1 March 2013, only the permanent foreign settlement should be reported towards the administration (District Office, Consulate. Earlier, temporary (more than 3 months settlement was also obligatory to be reported. Many of the leaving Hungarians do not report their leaving, however working abroad for more than 3 months should be reported towards social insurance organizations and tax authorities. I would like to emphasise that my migration potential presentation does not show a direct correlation with the actual migration. However, this study might show the expected movement rates and the composition of emigrants.

High School Graduation Rates:Alternative Methods and Implications

Directory of Open Access Journals (Sweden)

Jing Miao

2004-10-01

Full Text Available The No Child Left Behind Act has brought great attention to the high school graduation rate as one of the mandatory accountability measures for public school systems. However, there is no consensus on how to calculate the high school graduation rate given the lack of longitudinal databases that track individual students. This study reviews literature on and practices in reporting high school graduation rates, compares graduation rate estimates yielded from alternative methods, and estimates discrepancies between alternative results at national, state, and state ethnic group levels. Despite the graduation rate method used, results indicate that high school graduation rates in the U.S. have been declining in recent years and that graduation rates for black and Hispanic students lag substantially behind those of white students. As to graduation rate method preferred, this study found no evidence that the conceptually more complex methods yield more accurate or valid graduation rate estimates than the simpler methods.

Age- and time-dependent changes in the rates of radiation-induced cancers in patients with ankylosing spondylitis following a single course of X-ray treatment

International Nuclear Information System (INIS)

Smith, P.G.; Doll, R.

1978-01-01

The causes of death have been analysed in 14111 patients with ankylosing spondylitis following a single course of X-ray treatment. Patients who were re-treated with X-rays were followed until the end of the year following their second course of treatment and deaths subsequent to this time were ignored. An attempt was made to follow the remaining patients to 1 January 1970, or their date of death or emigration, whichever was the earlier. A total of 7455 (52.8%) patients were re-treated before 1 January 1970, 1759 (12.5%) patients had died and 269 (1.9%) had emigrated. A total of 208 (1.5%) patients were lost to follow-up and the remaining 4420 (31.3%), who had all received one course of treatment, were alive. The number of deaths from all causes was 66% greater than the expected number computed from national age and sex specific mortality rates. There were 31 deaths from leukaemia (6.5 expected), 259 from cancers of ''heavily irradiated'' sites (167.5 expected) and 79 from cancers of ''lightly irradiated'' sites, which was not significantly higher than the 65.6 expected. The ratio of observed to expected deaths and the excess death rate from leukaemia was greatest in the period three to five years after first treatment and subsequently declined. The ratio of observed to expected deaths from cancers of heavily irradiated sites was high in the two years following treatment, fell to a minimum six to eight years after treatment and then rose. Data for individual heavily irradiated sites showed little variation in the ratio of observed to expected numbers of deaths, apart from those due to tumours of the spinal cord. The ratio of observed to expected deaths for both leukaemia and cancers of the heavily irradiated sites showed no apparent change according to the age of the patients at their first treatment but the excess death rate showed a highly significant increase with increasing age at first treatment

The Russian Chursh Abroad and Vietnam war according to emigre ecclesiastical periodicals

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Anashkin Dmitrii

2015-03-01

Full Text Available Soon after the end of World War II, there arose in the world two opposing systems, between which there began an intense conflict. One manifestation of this confl ict was the outbreak of local wars in different parts of the world. The most violent was certainly the war in Vietnam. For the Russian Church Abroad, which comprised the most conservative elements of the Russian emigration, the war in Vietnam was a war with the evil power of this world: communism. In this war the United States protected not only its own interests but also those of the entire free world against the God-fighters who had seized their homeland, Russia. It was precisely communism that the Russian Church Abroad opposed, not the Vietnamese people, towards whom it was very sympathetic. The church press reported enthusiastically about the heroism of American soldiers, particularly those of Russian heritage serving in the American armed forces. At the same time, it noted various problems among the American soldiers in Vietnam, particularly the widespread use of narcotics. The various anti-war demonstrations were regarded by the Church Abroad as a capitulation of the free world in the face of evil. The peace talks in Indochina were likewise regarded negatively. At the same time, this intense anticommunism had its negative sides, making any objective analysis of events very diffi cult, which in turn led to one-sided views.

High School Graduation Rates:Alternative Methods and Implications

OpenAIRE

Jing Miao; Walt Haney

2004-01-01

The No Child Left Behind Act has brought great attention to the high school graduation rate as one of the mandatory accountability measures for public school systems. However, there is no consensus on how to calculate the high school graduation rate given the lack of longitudinal databases that track individual students. This study reviews literature on and practices in reporting high school graduation rates, compares graduation rate estimates yielded from alternative methods, and estimates d...

Emigration of Natural and Hatchery Chinook Salmon and Steelhead Smolts from the Imnaha River, Oregon, Progress Report 2000-2002.

Energy Technology Data Exchange (ETDEWEB)

Cleary, Peter; Kucera, Paul; Blenden, Michael

2003-12-01

This report summarizes the emigration studies of the Nez Perce Tribe in the Imnaha River subbasin during the 2001 and 2002 migration years. A migration year for the Imnaha River is defined here as beginning July 31 of the previous year and ending July 30 the following year. The conclusion of the studies at the end of migration year 2002 marked the 11th year of the Nez Perce Tribe's Lower Snake River Emigration Studies. The Nez Perce Tribe has participated in the Fish Passage Center's Smolt Monitoring Program for nine of the 11 years. These studies collect and tag juvenile chinook salmon and steelhead at two locations in the fall, rkm 74 and rkm 7, and at rkm 7 during the spring. Data from captured and tagged fish provide an evaluation of hatchery production and releases strategies, post release survival of hatchery chinook salmon, abundance of natural chinook salmon, and downstream survival and arrival timing of natural and hatchery chinook salmon and steelhead. The hydrologic conditions that migrating fish encountered in 2001 were characterized as a drought and conditions in 2002 were characterized as below average. Hatchery chinook salmon had a mean fork length that was 34 mm greater in 2001 and 35 mm greater in 2002 than the mean fork length of natural chinook smolts. Hatchery steelhead smolt mean fork lengths were 39 mm greater than natural steelhead smolts in 2001 and 44 mm greater than natural steelhead smolt fork lengths in 2002. A significant difference (p < 0.05) between hatchery and natural chinook salmon and steelhead fork lengths has been documented by these emigration studies from 1997 to 2002. Hatchery chinook salmon were volitionally released in 2001 and 2002 and the 90% arrivals for 2001 and 2002 at the lower rkm 7 trap were within the range of past observations of 22 to 38 days observed in 1999 and 2000. We estimated that 93.9% of the 123,014 hatchery chinook salmon released in 2001 survived to the lower trap and 90.2% of the 303

High rate response of ultra-high-performance fiber-reinforced concretes under direct tension

Energy Technology Data Exchange (ETDEWEB)

Tran, Ngoc Thanh [Department of Civil and Environmental Engineering, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747 (Korea, Republic of); Tran, Tuan Kiet [Department of Civil and Environmental Engineering, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747 (Korea, Republic of); Department of Civil Engineering and Applied Mechanics, Ho Chi Minh City University of Technology and Education, 01 Vo Van Ngan, Thu Duc District, Ho Chi Minh City (Viet Nam); Kim, Dong Joo, E-mail: djkim75@sejong.ac.kr [Department of Civil and Environmental Engineering, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747 (Korea, Republic of)

2015-03-15

The tensile response of ultra-high-performance fiber-reinforced concretes (UHPFRCs) at high strain rates (5–24 s{sup −} {sup 1}) was investigated. Three types of steel fibers, including twisted, long and short smooth steel fibers, were added by 1.5% volume content in an ultra high performance concrete (UHPC) with a compressive strength of 180 MPa. Two different cross sections, 25 × 25 and 25 × 50 mm{sup 2}, of tensile specimens were used to investigate the effect of the cross section area on the measured tensile response of UHPFRCs. Although all the three fibers generated strain hardening behavior even at high strain rates, long smooth fibers produced the highest tensile resistance at high rates whereas twisted fiber did at static rate. The breakages of twisted fibers were observed from the specimens tested at high strain rates unlike smooth steel fibers. The tensile behavior of UHPFRCs at high strain rates was clearly influenced by the specimen size, especially in post-cracking strength.

Reviving a Community, Modernizing an Industry: Ireland's Furniture College.

Science.gov (United States)

Regional Technology Strategies, Inc., Carrboro, NC.

Connemara, a rural region in Ireland, is characterized by high unemployment, high emigration, poor infrastructure, inadequate public services, and a low rate of transfer to third-level education. To address the situation, the Galway-Mayo Institute of Technology (GMIT), joined forces with Connemara West (a community-owned development organization…

High-rate lithium thionyl chloride cells

Science.gov (United States)

Goebel, F.

1982-03-01

A high-rate C cell with disc electrodes was developed to demonstrate current rates which are comparable to other primary systems. The tests performed established the limits of abuse beyond which the cell becomes hazardous. Tests include: impact, shock, and vibration tests; temperature cycling; and salt water immersion of fresh cells.

If there were a ‘Highly Skilled Red Octopus’? The Case of Italian Highly Skilled Mobility at Times of Crisis

OpenAIRE

Minneci, Fabiana

2015-01-01

The aim of the present paper is to provide an analysis of the recent growth in emigration of highly skilled workers from Italy and to put it in the context of the overall crisis influencing Southern European countries. In doing so, a comparison of two recent studies on the phenomenon will be presented, highlighting the fact that nowadays highly skilled flows tend to have distinctive features, both in terms of forms and trajectories. Attention will be given to under-stu...

Quantum data locking for high-rate private communication

OpenAIRE

Lupo, Cosmo; Lloyd, Seth

2015-01-01

We show that, if the accessible information is used as a security quantifier, quantum channels with a certain symmetry can convey private messages at a tremendously high rate, as high as less than one bit below the rate of non-private classical communication. This result is obtained by exploiting the quantum data locking effect. The price to pay to achieve such a high private communication rate is that accessible information security is in general not composable. However, composable security ...

Thrombus Formation at High Shear Rates.

Science.gov (United States)

Casa, Lauren D C; Ku, David N

2017-06-21

The final common pathway in myocardial infarction and ischemic stroke is occlusion of blood flow from a thrombus forming under high shear rates in arteries. A high-shear thrombus forms rapidly and is distinct from the slow formation of coagulation that occurs in stagnant blood. Thrombosis at high shear rates depends primarily on the long protein von Willebrand factor (vWF) and platelets, with hemodynamics playing an important role in each stage of thrombus formation, including vWF binding, platelet adhesion, platelet activation, and rapid thrombus growth. The prediction of high-shear thrombosis is a major area of biofluid mechanics in which point-of-care testing and computational modeling are promising future directions for clinically relevant research. Further research in this area will enable identification of patients at high risk for arterial thrombosis, improve prevention and treatment based on shear-dependent biological mechanisms, and improve blood-contacting device design to reduce thrombosis risk.

High Heating Rates Affect Greatly the Inactivation Rate of Escherichia coli

Science.gov (United States)

Huertas, Juan-Pablo; Aznar, Arantxa; Esnoz, Arturo; Fernández, Pablo S.; Iguaz, Asunción; Periago, Paula M.; Palop, Alfredo

2016-01-01

Heat resistance of microorganisms can be affected by different influencing factors. Although, the effect of heating rates has been scarcely explored by the scientific community, recent researches have unraveled its important effect on the thermal resistance of different species of vegetative bacteria. Typically heating rates described in the literature ranged from 1 to 20°C/min but the impact of much higher heating rates is unclear. The aim of this research was to explore the effect of different heating rates, such as those currently achieved in the heat exchangers used in the food industry, on the heat resistance of Escherichia coli. A pilot plant tubular heat exchanger and a thermoresistometer Mastia were used for this purpose. Results showed that fast heating rates had a deep impact on the thermal resistance of E. coli. Heating rates between 20 and 50°C/min were achieved in the heat exchanger, which were much slower than those around 20°C/s achieved in the thermoresistometer. In all cases, these high heating rates led to higher inactivation than expected: in the heat exchanger, for all the experiments performed, when the observed inactivation had reached about seven log cycles, the predictions estimated about 1 log cycle of inactivation; in the thermoresistometer these differences between observed and predicted values were even more than 10 times higher, from 4.07 log cycles observed to 0.34 predicted at a flow rate of 70 mL/min and a maximum heating rate of 14.7°C/s. A quantification of the impact of the heating rates on the level of inactivation achieved was established. These results point out the important effect that the heating rate has on the thermal resistance of E. coli, with high heating rates resulting in an additional sensitization to heat and therefore an effective food safety strategy in terms of food processing. PMID:27563300

Semi-solid electrodes having high rate capability

Energy Technology Data Exchange (ETDEWEB)

Chiang, Yet-Ming; Duduta, Mihai; Holman, Richard; Limthongkul, Pimpa; Tan, Taison

2017-11-28

Embodiments described herein relate generally to electrochemical cells having high rate capability, and more particularly to devices, systems and methods of producing high capacity and high rate capability batteries having relatively thick semi-solid electrodes. In some embodiments, an electrochemical cell includes an anode, a semi-solid cathode that includes a suspension of an active material and a conductive material in a liquid electrolyte, and an ion permeable membrane disposed between the anode and the cathode. The semi-solid cathode has a thickness in the range of about 250 .mu.m-2,500 .mu.m, and the electrochemical cell has an area specific capacity of at least 5 mAh/cm.sup.2 at a C-rate of C/2.

Solidification at the High and Low Rate Extreme

Energy Technology Data Exchange (ETDEWEB)

Meco, Halim [Iowa State Univ., Ames, IA (United States)

2004-12-19

The microstructures formed upon solidification are strongly influenced by the imposed growth rates on an alloy system. Depending on the characteristics of the solidification process, a wide range of growth rates is accessible. The prevailing solidification mechanisms, and thus the final microstructure of the alloy, are governed by these imposed growth rates. At the high rate extreme, for instance, one can have access to novel microstructures that are unattainable at low growth rates. While the low growth rates can be utilized for the study of the intrinsic growth behavior of a certain phase growing from the melt. Although the length scales associated with certain processes, such as capillarity, and the diffusion of heat and solute, are different at low and high rate extremes, the phenomena that govern the selection of a certain microstructural length scale or a growth mode are the same. Consequently, one can analyze the solidification phenomena at both high and low rates by using the same governing principles. In this study, we examined the microstructural control at both low and high extremes. For the high rate extreme, the formation of crystalline products and factors that control the microstructure during rapid solidification by free-jet melt spinning are examined in Fe-Si-B system. Particular attention was given to the behavior of the melt pool at different quench-wheel speeds. Since the solidification process takes place within the melt-pool that forms on the rotating quench-wheel, we examined the influence of melt-pool dynamics on nucleation and growth of crystalline solidification products and glass formation. High-speed imaging of the melt-pool, analysis of ribbon microstructure, and measurement of ribbon geometry and surface character all indicate upper and lower limits for melt-spinning rates for which nucleation can be avoided, and fully amorphous ribbons can be achieved. Comparison of the relevant time scales reveals that surface-controlled melt

Dynamic High-Temperature Characterization of an Iridium Alloy in Compression at High Strain Rates

Energy Technology Data Exchange (ETDEWEB)

Song, Bo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Experimental Environment Simulation Dept.; Nelson, Kevin [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Mechanics of Materials Dept.; Lipinski, Ronald J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Nuclear Fuel Cycle Technology Dept.; Bignell, John L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Structural and Thermal Analysis Dept.; Ulrich, G. B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Radioisotope Power Systems Program; George, E. P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Radioisotope Power Systems Program

2014-06-01

Iridium alloys have superior strength and ductility at elevated temperatures, making them useful as structural materials for certain high-temperature applications. However, experimental data on their high-temperature high-strain-rate performance are needed for understanding high-speed impacts in severe elevated-temperature environments. Kolsky bars (also called split Hopkinson bars) have been extensively employed for high-strain-rate characterization of materials at room temperature, but it has been challenging to adapt them for the measurement of dynamic properties at high temperatures. Current high-temperature Kolsky compression bar techniques are not capable of obtaining satisfactory high-temperature high-strain-rate stress-strain response of thin iridium specimens investigated in this study. We analyzed the difficulties encountered in high-temperature Kolsky compression bar testing of thin iridium alloy specimens. Appropriate modifications were made to the current high-temperature Kolsky compression bar technique to obtain reliable compressive stress-strain response of an iridium alloy at high strain rates (300 – 10000 s^-1) and temperatures (750°C and 1030°C). Uncertainties in such high-temperature high-strain-rate experiments on thin iridium specimens were also analyzed. The compressive stress-strain response of the iridium alloy showed significant sensitivity to strain rate and temperature.

New Maids and Caretakers in Paris?: The Reactivation of Transnational Social Fields of Spanish Emigration Following the Economic Crisis

Directory of Open Access Journals (Sweden)

Laura Oso

2017-12-01

Full Text Available This article analyses the migration of Spanish women to France following the 2008 economic crisis, considering the reactivation of the transnational social fields that have been built up between the two countries over the years. It reveals how the recession has led to a renewal of the gender-based labour niches filled by women emigrating to Paris in the period between 1950 and 1970 (bonnes à tout faire or maid, domestic workers, caretakers and cleaners, stemming from the reactivation of transnational fields built up through social networks woven by the various migratory trends. It provides an insight into the way these transnational fields are linked to global production and reproduction chains in terms of the patriarchal reorganisation of the labour market and workforce. It concludes that the economic crisis has reinforced traditional social reproduction channels rooted in gender-based sources of employment.

High Strain Rate Characterisation of Composite Materials

DEFF Research Database (Denmark)

Eriksen, Rasmus Normann Wilken

-reinforced polymers, were considered, and it was first shown that the loading history controls equilibrium process. Then the High-speed servo-hydraulic test machine was analysed in terms its ability to create a state of constant strain rate in the specimen. The invertible inertial forces in the load train prevented...... from designing and constructing a high-speed servo-hydraulic test machine and by performing a comprehensive test series. The difficulties encountered in the test work could be addressed with the developed analysis. The conclusion was that the High-speed servo-hydraulic test machine is less suited...... for testing fibre-reinforced polymers due to their elastic behaviour and low strain to failure. This is problematic as the High-speed servo-hydraulic test machine closes the gap between quasi-static tests rates and lower strain rates, which are achievable with the Split Hopkinson Pressure Bar. The Split...

Global Personality Norms: Multicultural, Multinational, and Managerial

Science.gov (United States)

Oswald, Frederick L.

2008-01-01

The critical importance of understanding, selecting, and developing global management talent--management operating within internationally diverse interpersonal and situational contexts--has emerged from the increasing globalization of business and the concomitant high rates of immigration, emigration, and expatriation. With an awareness of this…

Authoritative school climate and high school dropout rates.

Science.gov (United States)

Jia, Yuane; Konold, Timothy R; Cornell, Dewey

2016-06-01

This study tested the association between school-wide measures of an authoritative school climate and high school dropout rates in a statewide sample of 315 high schools. Regression models at the school level of analysis used teacher and student measures of disciplinary structure, student support, and academic expectations to predict overall high school dropout rates. Analyses controlled for school demographics of school enrollment size, percentage of low-income students, percentage of minority students, and urbanicity. Consistent with authoritative school climate theory, moderation analyses found that when students perceive their teachers as supportive, high academic expectations are associated with lower dropout rates. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

High-repetition-rate short-pulse gas discharge.

Science.gov (United States)

Tulip, J; Seguin, H; Mace, P N

1979-09-01

A high-average-power short-pulse gas discharge is described. This consists of a volume-preionized transverse discharge of the type used in gas lasers driven by a Blumlein energy storage circuit. The Blumlein circuit is fabricated from coaxial cable, is pulse-charged from a high-repetition-rate Marx-bank generator, and is switched by a high-repetition-rate segmented rail gap. The operation of this discharge under conditions typical of rare-gas halide lasers is described. A maximum of 900 pps was obtained, giving a power flow into the discharge of 30 kW.

HIGH-RATE DISINFECTION TECHNIQUES FOR COMBIND SEWER OVERFLOW

Science.gov (United States)

This paper presents high-rate disinfection technologies for combined sewer overflow (CSO). The high-rate disinfection technologies of interest are: chlorination/dechlorination, ultraviolet light irradiation (UV), chlorine dioxide (ClO2 ), ozone (O3), peracetic acid (CH3COOOH )...

Homeostatic properties and phenotypic maturation of murine CD4+ pre-thymic emigrants in the thymus.

Directory of Open Access Journals (Sweden)

Jie Dong

Full Text Available After a tightly regulated developmental program in the thymus, "mature" single positive (SP thymocytes leave the thymus and enter the periphery. These newly arrived recent thymic emigrants (RTEs are phenotypically and functionally immature, and will complete a dynamic maturation in the peripheral lymphoid organs before being licensed to be resident naïve T cells. To study the early events occurring in the RTE maturation process, we identified the phenotype of CD4(+ pre-RTEs, a population of CD4(+ SP thymocytes that have acquired the thymus egress capability. Compared to peripheral naïve T cells, CD4(+ pre-RTEs displayed superior survival capability in lymphoreplete mice and faster proliferation under lymphopenic condition. The differences in Bcl2/Bim expression and/or heightened IL-7 signaling pathway may account for the pre-RTEs' better responsiveness to homeostatic signals. Qa2, the expression of which indicates the phenotypic maturation of SPs and RTEs, was found to be upregulated in CD4(+ pre-RTEs in thymic perivascular space. Migratory dendritic cells that surround this region contribute to Qa2 expression in pre-RTEs. The dendritic cell-driven Qa2 induction of CD4(+ pre-RTEs is independent of MHC class II and Aire molecules.

Introduction to State Estimation of High-Rate System Dynamics.

Science.gov (United States)

Hong, Jonathan; Laflamme, Simon; Dodson, Jacob; Joyce, Bryan

2018-01-13

Engineering systems experiencing high-rate dynamic events, including airbags, debris detection, and active blast protection systems, could benefit from real-time observability for enhanced performance. However, the task of high-rate state estimation is challenging, in particular for real-time applications where the rate of the observer's convergence needs to be in the microsecond range. This paper identifies the challenges of state estimation of high-rate systems and discusses the fundamental characteristics of high-rate systems. A survey of applications and methods for estimators that have the potential to produce accurate estimations for a complex system experiencing highly dynamic events is presented. It is argued that adaptive observers are important to this research. In particular, adaptive data-driven observers are advantageous due to their adaptability and lack of dependence on the system model.

Productive Reintegration of Return Emigrants and Rural Tourism: Life and Work Experiences in Sardinia (Italy and in a Mountain Area in the Province of Marrakech (Morocco

Directory of Open Access Journals (Sweden)

Maria Luisa Gentileschi

2006-09-01

Full Text Available The paper provides a contribution to the formulation of return migration policies that seek to harness the skills gained by emigrants and channel their savings into the creation of small businesses within a local development scheme. We have drawn from experiences described by return emigrants, gathered in Sardinia and in the Marrakech province in Morocco, to formulate measures capable of generating positive opportunities for encouraging the return of migrants to their home areas, utilizing the skills gained in the hospitality industry in Europe and investing their savings in their country. The measures are also designed to offer return migrants an alternative to settling in urban destinations. The case study is concerned with a rural tourism initiative in subcoastal and interior areas as an alternative to marine and coastal tourism. Based on the premise that only those areas with a natural and cultural heritage offer good potential for the development of rural tourism, the following conclusions are presented: a one seemingly useful form of action is for the authorities in the host countries to organise training courses for migrant workers, within the cooperation framework for assisting migrants to return to their home countries; b it is essential for local authorities in the migrants’ home countries to improve transportation systems, facilities and tourist services in general; c equally important in the home countries is the adoption of measures aimed at the recognition, rehabilitation and enhancement of the archaeological heritage, material culture and of traditions in general, together with the natural/ environmental resources for an integrated tourist product.

Development of ultra high speed photographic system using high repetition rate visible laser

International Nuclear Information System (INIS)

Lee, Jong Min; Cha, Byung Hun; Kim, Sung Ho; Kim, Jung Bog; Lim, Chang Hwan; Cha, Hyung Ki; Song, Kyu Seok; Lee, Byung Deok; Rhi, Jong Hoon; Baik, Dae Hyun; Han, Jae Min; Rho, Si Pyo; Lee, Byung Cheol; Jeong, Do Yung; Choi, An Seong; Jeong, Chan Ik; Park, Dae Ung; Jeong, Sung Min; Lee, Sang Kil; Kim, Heon Jun; Jang, Rae gak; Jo, Do Hun; Park, Min Young

1992-12-01

The goal of this project is to develop and commercialize a high speed photographic system equipped with a high repetition rate visible laser. The developed system provides the characteristics of high time resolution and large number of frames. The system consists of 10 W air cooled CVL or a 30 W water cooled CVL, a rotating drum-type high speed camera with the framing rate of 35,000 fps, and a automatic control device. The system has the performance of 10 nsec time resolution, 35,000 fps framing rate, and 250 picture frames. The high speed photographic systems are widely applied to the fields such as high-efficient engine development, high-speed vibration analysis, shock wave propagation study, flow visualization analysis, weapon development, etc. (Author)

T-cell receptor excision circles (TREC) in CD4+ and CD8+ T-cell subpopulations in atopic dermatitis and psoriasis show major differences in the emission of recent thymic emigrants

DEFF Research Database (Denmark)

Just, Helle L; Deleuran, Mette; Vestergaard, Christian

2008-01-01

. In contrast, both men and women with psoriasis had significantly reduced TREC levels, which were, on average, only 30% of that of healthy persons. In atopic dermatitis the levels of TREC declined with increasing levels of IgE, disease intensity and extent of eczema. Furthermore, patients with atopic......-cells, this indicates that atopic dermatitis patients can have compensatory emissions of thymic emigrants, whereas psoriatic patients do not, thus supporting different thymic function in these two diseases....

Quantum data locking for high-rate private communication

International Nuclear Information System (INIS)

Lupo, Cosmo; Lloyd, Seth

2015-01-01

We show that, if the accessible information is used as a security quantifier, quantum channels with a certain symmetry can convey private messages at a tremendously high rate, as high as less than one bit below the rate of non-private classical communication. This result is obtained by exploiting the quantum data locking effect. The price to pay to achieve such a high private communication rate is that accessible information security is in general not composable. However, composable security holds against an eavesdropper who is forced to measure her share of the quantum system within a finite time after she gets it. (paper)

Migration Flow and Its Impact on Tuberculosis Notification in Portugal.

Science.gov (United States)

Dias, Ana; Gaio, Rita; Sousa, Pedro; Gomes, Marta; Oliveira, Olena; Duarte, Raquel

2018-01-01

Tuberculosis notification in Portugal has decreased in the last few years. As a consequence of the economic crisis, emigration has increased and immigration has decreased. Immigrants are a risk group for tuberculosis. Most emigrants are 20-44 years old and belong to the age group most affected by tuberculosis. To describe the decrease in tuberculosis notification in Portugal over the last years from a demographical point of view. Mathematical analysis was performed to quantify the effect of the migration movements (separately and simultaneously) on tuberculosis notification in Portugal from 2008 to 2014. We calculated the estimated tuberculosis notification for each year during the period of study: 1) fixing immigration rate and tuberculosis rate in immigrants at 2008 values; 2) fixing emigration rate and tuberculosis rate in emigrants at 2008 values; 3) fixing both phenomenons at 2008 values. The differences between the observed and the estimated numbers were small (≤0.5 cases/100000 inhabitants). Impact of the migration movements on tuberculosis notification rate does not seem to be significant when analyzed for each phenomenon individually and simultaneously, by our model. This might mean that we have to concentrate our efforts in other risk factors for tuberculosis. Copyright © 2017 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.

[Max Isserlin, Kantian orientation at Königsberg, psychotherapist with Kraepelin, founder of child psychiatry at Munich, emigrant to Britain].

Science.gov (United States)

Peters, U H

2002-01-01

This account of the life and work of Max Isserlin (1879 - 1941) wants to be a reminder of a German-Jewish fate next to Kraepelin and as a forced emigrant. Immediately after his studies at Königsberg Isserlin in 1903 came to Kraepelin at Heidelberg, later he followed him to Munich. All his life he kept a Kantian orientation and defended Kraepelin's positions out of this background. Kraepelin entrusted to him all of psychotherapy, theory and practice, which Isserlin for at least 18 years gave courses of in Kraepelin's department. His textbook of psychotherapy thus transmissions Kraepelins convictions about this topic also. During World War I Isserlin was the head of a field-hospital for brain damaged soldiers and continued working this way after the end of the war. Finally he became the founder of child psychiatry in Munich, until he was forced to leave Germany for Britain with a heavy heart.

High Graduate Unemployment Rate and Taiwanese Undergraduate Education

Science.gov (United States)

Wu, Chih-Chun

2011-01-01

An expansion in higher education in combination with the recent global economic recession has resulted in a high college graduate unemployment rate in Taiwan. This study investigates how the high unemployment rate and financial constraints caused by economic cutbacks have shaped undergraduates' class choices, job needs, and future income…

High strain rate behaviour of polypropylene microfoams

Science.gov (United States)

Gómez-del Río, T.; Garrido, M. A.; Rodríguez, J.; Arencón, D.; Martínez, A. B.

2012-08-01

Microcellular materials such as polypropylene foams are often used in protective applications and passive safety for packaging (electronic components, aeronautical structures, food, etc.) or personal safety (helmets, knee-pads, etc.). In such applications the foams which are used are often designed to absorb the maximum energy and are generally subjected to severe loadings involving high strain rates. The manufacture process to obtain polymeric microcellular foams is based on the polymer saturation with a supercritical gas, at high temperature and pressure. This method presents several advantages over the conventional injection moulding techniques which make it industrially feasible. However, the effect of processing conditions such as blowing agent, concentration and microfoaming time and/or temperature on the microstructure of the resulting microcellular polymer (density, cell size and geometry) is not yet set up. The compressive mechanical behaviour of several microcellular polypropylene foams has been investigated over a wide range of strain rates (0.001 to 3000 s-1) in order to show the effects of the processing parameters and strain rate on the mechanical properties. High strain rate tests were performed using a Split Hopkinson Pressure Bar apparatus (SHPB). Polypropylene and polyethylene-ethylene block copolymer foams of various densities were considered.

Temporal dynamics of high repetition rate pulsed single longitudinal ...

Indian Academy of Sciences (India)

ing (GIG) cavity, single-mode dye laser pumped by high repetition rate ... in a high loss cavity, a detailed theoretical study and optimization of cavity ..... rate for high conversion efficiency and longer pulse width of the single-mode dye laser.

Innere Emigration und Diktatur die getarnten Botschaften in den Opern der meister aus bojana von Konstantin Iliev und der gefesselte Prometeus von Lazar Nikolov

Directory of Open Access Journals (Sweden)

Kostakeva Maria

2004-01-01

Full Text Available (nemački Die Frage der "inneren Emigration" in den ehemaligen kommunistischen Ländern Europas wird an Beispielen zweier Opern der wichtigen bulgarischen Komponisten Konstantin Iliev und Lazar Nikolov untersucht. Ähnlich wie Paul Hindemith in Mathis der Maler, in Ilievs Meister aus Bojana (1962, kam die Inspiration von einer mittelalterlichen Legende her, und iM Mittelpunkt des Dramas steht das Problem der Freiheit der Schöpfer unter der dogmatischen Gewalt. IM Gefesselten Prometeus (1972 von Nikolov ist die Hauptperson als Symbol des Protests gegen die Tyrannei und die Unterdrückung zu verstehen und so lässt sich in allen Zeiten politisch interpretieren, umso mehr bei einem kommunistischen Regime.

A digital approach for real time high-rate high-resolution radiation measurements

International Nuclear Information System (INIS)

Gerardi, G.; Abbene, L.

2014-01-01

Modern spectrometers are currently developed by using digital pulse processing (DPP) systems, showing several advantages over traditional analog electronics. The aim of this work is to present digital strategies, in a time domain, for the development of real time high-rate high-resolution spectrometers. We propose a digital method, based on the single delay line (SDL) shaping technique, able to perform multi-parameter analysis with high performance even at high photon counting rates. A robust pulse shape and height analysis (PSHA), applied on single isolated time windows of the detector output waveforms, is presented. The potentialities of the proposed strategy are highlighted through both theoretical and experimental approaches. To strengthen our approach, the implementation of the method on a real-time system together with some experimental results are presented. X-ray spectra measurements with a semiconductor detector are performed both at low and high photon counting rates (up to 1.1 Mcps)

A digital approach for real time high-rate high-resolution radiation measurements

Energy Technology Data Exchange (ETDEWEB)

Gerardi, G.; Abbene, L., E-mail: leonardo.abbene@unipa.it

2014-12-21

Modern spectrometers are currently developed by using digital pulse processing (DPP) systems, showing several advantages over traditional analog electronics. The aim of this work is to present digital strategies, in a time domain, for the development of real time high-rate high-resolution spectrometers. We propose a digital method, based on the single delay line (SDL) shaping technique, able to perform multi-parameter analysis with high performance even at high photon counting rates. A robust pulse shape and height analysis (PSHA), applied on single isolated time windows of the detector output waveforms, is presented. The potentialities of the proposed strategy are highlighted through both theoretical and experimental approaches. To strengthen our approach, the implementation of the method on a real-time system together with some experimental results are presented. X-ray spectra measurements with a semiconductor detector are performed both at low and high photon counting rates (up to 1.1 Mcps)

High-rate performance of muon drift tube detectors

International Nuclear Information System (INIS)

Schwegler, Philipp

2014-01-01

The Large Hadron Collider (LHC) at the European Centre for Particle Physics, CERN, collides protons with an unprecedentedly high centre-of-mass energy and luminosity. The collision products are recorded and analysed by four big experiments, one of which is the ATLAS detector. In parallel with the first LHC run from 2009 to 2012, which culminated in the discovery of the last missing particle of the Standard Model of particle physics, the Higgs boson, planning of upgrades of the LHC for higher instantaneous luminosities (HL-LHC) is already progressing. The high instantaneous luminosity of the LHC puts high demands on the detectors with respect to radiation hardness and rate capability which are further increased with the luminosity upgrade. In this thesis, the limitations of the Muon Drift Tube (MDT) chambers of the ATLAS Muon Spectrometer at the high background counting rates at the LHC and performance of new small diameter muon drift tube (sMDT) detectors at the even higher background rates at HL-LHC are studied. The resolution and efficiency of sMDT chambers at high γ-ray and proton irradiation rates well beyond the ones expected at HL-LHC have been measured and the irradiation effects understood using detailed simulations. The sMDT chambers offer an about an order of magnitude better rate capability and are an ideal replacement for the MDT chambers because of compatibility of services and read-out. The limitations of the sMDT chambers are now in the read-out electronics, taken from the MDT chambers, to which improvements for even higher rate capability are proposed.

Solid state pump lasers with high power and high repetition rate

International Nuclear Information System (INIS)

Oba, Masaki; Kato, Masaaki; Arisawa, Takashi

1995-01-01

We built a laser diode pumped solid state green laser (LDPSSGL) rated at high repetition rate. Two laser heads are placed in one cavity with a rotator in between to design to avoid thermal lensing and thermal birefringence effect. Although average green laser power higher than 10 W was obtained at 1 kHz repetition rate with pulse width of 20-30 nsec, the beam quality was so much deteriorated that energy efficiency was as low as 2 %. Learning from this experience that high power oscillator causes a lot of thermal distortion not only in the laser rod but also in the Q-switch device, we proceeded to built a oscillator/amplifier system. A low power oscillator has a slab type crystal in the cavity. As a result spatial distribution of laser power was extremely improved. As we expect that the high repetition rate solid state laser should be CW operated Q-switch type laser from the view point of lifetime of diode lasers, a conventional arc lamp pumped CW Q-switch green YAG laser of which the repetition rate is changeable from 1 kHz to 5 kHz and the pulse width is 250-570 nsec was also tested to obtain pumping characteristics of a dye laser as a function of power, pulse width etc., and dye laser pulse width of 100-130 nsec were obtained. (author)

Semi-solid electrodes having high rate capability

Energy Technology Data Exchange (ETDEWEB)

Chiang, Yet-Ming; Duduta, Mihai; Holman, Richard; Limthongkul, Pimpa; Tan, Taison

2017-11-28

Embodiments described herein relate generally to electrochemical cells having high rate capability, and more particularly to devices, systems and methods of producing high capacity and high rate capability batteries having relatively thick semi-solid electrodes. In some embodiments, an electrochemical cell includes an anode and a semi-solid cathode. The semi-solid cathode includes a suspension of an active material of about 35% to about 75% by volume of an active material and about 0.5% to about 8% by volume of a conductive material in a non-aqueous liquid electrolyte. An ion-permeable membrane is disposed between the anode and the semi-solid cathode. The semi-solid cathode has a thickness of about 250 .mu.m to about 2,000 .mu.m, and the electrochemical cell has an area specific capacity of at least about 7 mAh/cm.sup.2 at a C-rate of C/4. In some embodiments, the semi-solid cathode slurry has a mixing index of at least about 0.9.

Teachers on the Move: International Migration of School Teachers from India

Science.gov (United States)

Sharma, Rashmi

2013-01-01

Emigration of qualified teachers from developing countries is a double loss for the source countries, not only leading to emigration of high-skill labour but also affecting their future developmental base when these countries are already struggling to meet the millennium development goals (MDGs) in education. This article discusses emigration of…

High resolution gamma-ray spectroscopy at high count rates with a prototype High Purity Germanium detector

Science.gov (United States)

Cooper, R. J.; Amman, M.; Vetter, K.

2018-04-01

High-resolution gamma-ray spectrometers are required for applications in nuclear safeguards, emergency response, and fundamental nuclear physics. To overcome one of the shortcomings of conventional High Purity Germanium (HPGe) detectors, we have developed a prototype device capable of achieving high event throughput and high energy resolution at very high count rates. This device, the design of which we have previously reported on, features a planar HPGe crystal with a reduced-capacitance strip electrode geometry. This design is intended to provide good energy resolution at the short shaping or digital filter times that are required for high rate operation and which are enabled by the fast charge collection afforded by the planar geometry crystal. In this work, we report on the initial performance of the system at count rates up to and including two million counts per second.

Environmental and Ethical Aspects of International Migration.

Science.gov (United States)

Abernethy, Virginia

1996-01-01

Well-intentioned U.S. immigration policy has two ill effects in that it encourages the belief that emigration can relieve overpopulation in third-world countries, maintaining high fertility rates, and it results in U.S. domestic population growth that threatens employment opportunities and the environment. (SLD)

Improving decision speed, accuracy and group cohesion through early information gathering in house-hunting ants.

Science.gov (United States)

Stroeymeyt, Nathalie; Giurfa, Martin; Franks, Nigel R

2010-09-29

Successful collective decision-making depends on groups of animals being able to make accurate choices while maintaining group cohesion. However, increasing accuracy and/or cohesion usually decreases decision speed and vice-versa. Such trade-offs are widespread in animal decision-making and result in various decision-making strategies that emphasize either speed or accuracy, depending on the context. Speed-accuracy trade-offs have been the object of many theoretical investigations, but these studies did not consider the possible effects of previous experience and/or knowledge of individuals on such trade-offs. In this study, we investigated how previous knowledge of their environment may affect emigration speed, nest choice and colony cohesion in emigrations of the house-hunting ant Temnothorax albipennis, a collective decision-making process subject to a classical speed-accuracy trade-off. Colonies allowed to explore a high quality nest site for one week before they were forced to emigrate found that nest and accepted it faster than emigrating naïve colonies. This resulted in increased speed in single choice emigrations and higher colony cohesion in binary choice emigrations. Additionally, colonies allowed to explore both high and low quality nest sites for one week prior to emigration remained more cohesive, made more accurate decisions and emigrated faster than emigrating naïve colonies. These results show that colonies gather and store information about available nest sites while their nest is still intact, and later retrieve and use this information when they need to emigrate. This improves colony performance. Early gathering of information for later use is therefore an effective strategy allowing T. albipennis colonies to improve simultaneously all aspects of the decision-making process--i.e. speed, accuracy and cohesion--and partly circumvent the speed-accuracy trade-off classically observed during emigrations. These findings should be taken into account

EMIGRATION FROM RUSSIA TO SOUTHEAST ASIA: FACTORS, GEOGRAPHY AND IMPLICATIONS

Directory of Open Access Journals (Sweden)

S. V. Ryazantsev

2017-01-01

Full Text Available The article describes the geographical features and trends of emigration of Russian citizens to the countries of Southeast Asia on the basis of a comparative analysis of domestic and foreign statistics. The results of sociological research in these countries have been used: interviews with experts and migrant citizens of various countries of the former USSR who live or stay in Southeast Asia for more than six months. In the course of the study, a comprehensive methodology was developed and the degree of favorableness of the migration and visa regimes of the Southeast Asian countries for Russian citizens has been assessed for a number of characteristics. Factors attracting Russian citizens to the countries of the region in the context of the migration theory of the factors of “pull and push” have been revealed. The socio-demographic structure of migration flows and the geographical features of the resettlement of Russian citizens in the Southeast Asian countries have been considered. The main channels of migration of Russian citizens to the region are given: temporary labor migration, migration for permanent residence, and tourism. Several groups of Russian-speaking migrants in the Southeast Asian countries have been singled out: migrants who have moved to permanent residence, as a rule, opened their own businesses; temporary migrant workers who work for several years in Southeast Asia, are tied to work and are planning to return to Russia after some time; temporary migrants who live in Southeast Asia for several months and periodically return to Russia; Russian women who married citizens of Thailand, Vietnam, Cambodia and other Southeast Asian countries – former students who studied in the USSR and Russia. On the basis of expert assessments, the types of migration and visa regimes of the countries of Southeast Asia for Russian citizens have been highlighted. Specifics of the formation of Russian-speaking communities in the countries of the

High strain rate behaviour of polypropylene microfoams

Directory of Open Access Journals (Sweden)

Martínez A.B.

2012-08-01

Full Text Available Microcellular materials such as polypropylene foams are often used in protective applications and passive safety for packaging (electronic components, aeronautical structures, food, etc. or personal safety (helmets, knee-pads, etc.. In such applications the foams which are used are often designed to absorb the maximum energy and are generally subjected to severe loadings involving high strain rates. The manufacture process to obtain polymeric microcellular foams is based on the polymer saturation with a supercritical gas, at high temperature and pressure. This method presents several advantages over the conventional injection moulding techniques which make it industrially feasible. However, the effect of processing conditions such as blowing agent, concentration and microfoaming time and/or temperature on the microstructure of the resulting microcellular polymer (density, cell size and geometry is not yet set up. The compressive mechanical behaviour of several microcellular polypropylene foams has been investigated over a wide range of strain rates (0.001 to 3000 s−1 in order to show the effects of the processing parameters and strain rate on the mechanical properties. High strain rate tests were performed using a Split Hopkinson Pressure Bar apparatus (SHPB. Polypropylene and polyethylene-ethylene block copolymer foams of various densities were considered.

The american high school graduation rate : trends and levels

OpenAIRE

Heckman, James J.; LaFontaine, Paul A.

2008-01-01

This paper uses multiple data sources and a unified methodology to estimate the trends and levels of the U.S. high school graduation rate. Correcting for important biases that plague previous calculations, we establish that (a) the true high school graduation rate is substantially lower than the official rate issued by the National Center for Educational Statistics; (b) it has been declining over the past 40 years; (c) majority/minority graduation rate differentials are substantial and have n...

Low dose rate and high dose rate intracavitary treatment for cervical cancer

International Nuclear Information System (INIS)

Hareyama, Masato; Oouchi, Atsushi; Shidou, Mitsuo

1997-01-01

From 1984 through 1993, 144 previous untreated patients with carcinoma of uterine cervix were treated with either low dose rate 137 Cs therapy (LDR) or high dose rate 60 Co therapy (HDR). The local failure rates for more than 2-years for the primary lesions were 11.8% (8 of 63 patients) for LDR and 18.0% (11 of 61 patients). Rectal complication rates were significantly lower for HDR versus LDR (14.3% VS. 32.8%. p<0.01). Also, bladder complication rates were significantly lower for HDR versus LDR (0% VS. 10.4%, p<0.005). Treatment results in term of local control were equivalent for HDR and LDR treatment. However, the incidence of complications was higher for the LDR group than for the HDR group. (author)

Transistor reset preamplifier for high-rate high-resolution spectroscopy

International Nuclear Information System (INIS)

Landis, D.A.; Cork, C.P.; Madden, N.W.; Goulding, F.S.

1981-10-01

Pulsed transistor reset of high resolution charge sensitive preamplifiers used in cooled semiconductor spectrometers can sometimes have an advantage over pulsed light reset systems. Several versions of transistor reset spectrometers using both silicon and germanium detectors have been built. This paper discusses the advantages of the transistor reset system and illustrates several configurations of the packages used for the FET and reset transistor. It also describes the preamplifer circuit and shows the performance of the spectrometer at high rates

Lithium thionyl chloride high rate discharge

Science.gov (United States)

Klinedinst, K. A.

1980-04-01

Improvements in high rate lithium thionyl chloride power technology achieved by varying the electrolyte composition, operating temperature, cathode design, and cathode composition are discussed. Discharge capacities are plotted as a function of current density, cell voltage, and temperature.

High frame rate synthetic aperture duplex imaging

DEFF Research Database (Denmark)

Stuart, Matthias Bo; Tomov, Borislav Gueorguiev; Pihl, Michael Johannes

2013-01-01

aperture flow imaging as demonstrated in this paper. Synthetic aperture, directional beamforming, and cross-correlation are used to produce B-mode and vector velocity images at high frame rates. The frame rate equals the effective pulse repetition frequency of each imaging mode. Emissions for making the B...... estimation is −1.8% and the relative standard deviation 5.4%. The approach can thus estimate both high and low velocities with equal accuracy and thereby makes it possible to present vector flow images with a high dynamic range. Measurements are made using the SARUS research scanner, a linear array......Conventional color flow images are limited in velocity range and can either show the high velocities in systole or be optimized for the lower diastolic velocities. The full dynamics of the flow is, thus, hard to visualize. The dynamic range can be significantly increased by employing synthetic...

High-Rate Performance of Muon Drift Tube Detectors

CERN Document Server

Schwegler, Philipp

The Large Hadron Collider (LHC) at the European Centre for Particle Physics, CERN, collides protons with an unprecedentedly high centre-of-mass energy and luminosity. The collision products are recorded and analysed by four big experiments, one of which is the ATLAS detector. In parallel with the first LHC run from 2009 to 2012, which culminated in the discovery of the last missing particle of the Standard Model of particle physics, the Higgs boson, planning of upgrades of the LHC for higher instantaneous luminosities (HL-LHC) is already progressing. The high instantaneous luminosity of the LHC puts high demands on the detectors with respect to radiation hardness and rate capability which are further increased with the luminosity upgrade. In this thesis, the limitations of the Muon Drift Tube (MDT) chambers of the ATLAS Muon Spectrometer at the high background counting rates at the LHC and performance of new small diameter muon drift tube (sMDT) detectors at the even higher background rates at HL-LHC are stud...

High energy high repetition-rate thin-disk amplifier for OPCPA pumping

Energy Technology Data Exchange (ETDEWEB)

Schulz, Michael

2013-08-15

The development of a pump laser system for a high power and high repetition rate optical parametric chirped-pulse amplification (OPCPA) is presented in this thesis. The OPCPA system requires pump pulse energies in the range of tens of millijoules at high repetition rates with sub-picosecond pulse durations. This can be achieved to some extend with Innoslab amplifier technology. However, scaling to higher pulse energies at high repetition rates may be problematic. With the thin-disk amplifier presented in this thesis, output energies of 140 mJ at 100 kHz repetition rate could be achieved in burst-mode operation, which is a world record for this type of laser amplifier. Due to its material and spectral properties, ytterbium doped YAG (Yb:YAG) is used as a gain medium for the high power amplifier stages. The low quantum defect and the comparatively large emission bandwidth makes this material the choice for high power operation and sub-picosecond compressed pulse durations. The output beam profile as well as the shape of the output bursts is ideal to pump an OPCPA system. An OPCPA output energy in the millijoule range with repetition rates of 100 kHz to 1 MHz is needed to generate seed pulses for the FEL and for the application as pump-probe laser at the FEL facility. Since the development of this laser system needs to meet requirements set by the Free-Electron Laser in Hamburg (FLASH), the amplifier is conceived for burst-mode operation. The main requirement is a high intra-burst pulse repetition rate of more than 100 kHz and a uniform pulse train (burst) with equal properties for every pulse. The burst-mode is an operation mode where the laser never reaches a lasing equilibrium, which means that the behavior of the amplifier is similar to a switch-on of the laser system for every burst. This makes the development of the amplifier system difficult. Therefore, an analytical model has been developed to study the amplification process during the burst. This includes the

High energy high repetition-rate thin-disk amplifier for OPCPA pumping

International Nuclear Information System (INIS)

Schulz, Michael

2013-08-01

The development of a pump laser system for a high power and high repetition rate optical parametric chirped-pulse amplification (OPCPA) is presented in this thesis. The OPCPA system requires pump pulse energies in the range of tens of millijoules at high repetition rates with sub-picosecond pulse durations. This can be achieved to some extend with Innoslab amplifier technology. However, scaling to higher pulse energies at high repetition rates may be problematic. With the thin-disk amplifier presented in this thesis, output energies of 140 mJ at 100 kHz repetition rate could be achieved in burst-mode operation, which is a world record for this type of laser amplifier. Due to its material and spectral properties, ytterbium doped YAG (Yb:YAG) is used as a gain medium for the high power amplifier stages. The low quantum defect and the comparatively large emission bandwidth makes this material the choice for high power operation and sub-picosecond compressed pulse durations. The output beam profile as well as the shape of the output bursts is ideal to pump an OPCPA system. An OPCPA output energy in the millijoule range with repetition rates of 100 kHz to 1 MHz is needed to generate seed pulses for the FEL and for the application as pump-probe laser at the FEL facility. Since the development of this laser system needs to meet requirements set by the Free-Electron Laser in Hamburg (FLASH), the amplifier is conceived for burst-mode operation. The main requirement is a high intra-burst pulse repetition rate of more than 100 kHz and a uniform pulse train (burst) with equal properties for every pulse. The burst-mode is an operation mode where the laser never reaches a lasing equilibrium, which means that the behavior of the amplifier is similar to a switch-on of the laser system for every burst. This makes the development of the amplifier system difficult. Therefore, an analytical model has been developed to study the amplification process during the burst. This includes the

Circuit and interconnect design for high bit-rate applications

NARCIS (Netherlands)

Veenstra, H.

2006-01-01

This thesis presents circuit and interconnect design techniques and design flows that address the most difficult and ill-defined aspects of the design of ICs for high bit-rate applications. Bottlenecks in interconnect design, circuit design and on-chip signal distribution for high bit-rate

Parenting from Abroad: Migration, Nonresident Father Involvement, and Children's Education in Mexico

Science.gov (United States)

Nobles, Jenna

2011-01-01

In Mexico, a country with high emigration rates, parental migration matches divorce as a contributor to child-father separation. Yet little has been written about children's relationships with migrating parents. In this study, I use nationally representative data from the 2005 Mexican Family Life Survey to model variation in the interaction…

High rate tests of the LHCb RICH Upgrade system

CERN Multimedia

Blago, Michele Piero

2016-01-01

One of the biggest challenges for the upgrade of the LHCb RICH detectors from 2020 is to readout the photon detectors at the full 40 MHz rate of the LHC proton-proton collisions. A test facility has been setup at CERN with the purpose to investigate the behaviour of the Multi Anode PMTs, which have been proposed for the upgrade, and their readout electronics at high trigger rates. The MaPMTs are illuminated with a monochromatic laser that can be triggered independently of the readout electronics. A first series of tests, including threshold scans, is performed at low trigger rates (20 kHz) for both the readout and the laser with the purpose to characterise the behaviour of the system under test. Then the trigger rate is increased in two separate steps. First the MaPMTs are exposed to high illumination by triggering the pulsed laser at a high (20 MHz) repetition rate while the DAQ is readout at the same low rate as before. In this way the performance of the MaPMTs and the attached electronics can be evaluated ...

Improving decision speed, accuracy and group cohesion through early information gathering in house-hunting ants.

Directory of Open Access Journals (Sweden)

Nathalie Stroeymeyt

Full Text Available BACKGROUND: Successful collective decision-making depends on groups of animals being able to make accurate choices while maintaining group cohesion. However, increasing accuracy and/or cohesion usually decreases decision speed and vice-versa. Such trade-offs are widespread in animal decision-making and result in various decision-making strategies that emphasize either speed or accuracy, depending on the context. Speed-accuracy trade-offs have been the object of many theoretical investigations, but these studies did not consider the possible effects of previous experience and/or knowledge of individuals on such trade-offs. In this study, we investigated how previous knowledge of their environment may affect emigration speed, nest choice and colony cohesion in emigrations of the house-hunting ant Temnothorax albipennis, a collective decision-making process subject to a classical speed-accuracy trade-off. METHODOLOGY/PRINCIPAL FINDINGS: Colonies allowed to explore a high quality nest site for one week before they were forced to emigrate found that nest and accepted it faster than emigrating naïve colonies. This resulted in increased speed in single choice emigrations and higher colony cohesion in binary choice emigrations. Additionally, colonies allowed to explore both high and low quality nest sites for one week prior to emigration remained more cohesive, made more accurate decisions and emigrated faster than emigrating naïve colonies. CONCLUSIONS/SIGNIFICANCE: These results show that colonies gather and store information about available nest sites while their nest is still intact, and later retrieve and use this information when they need to emigrate. This improves colony performance. Early gathering of information for later use is therefore an effective strategy allowing T. albipennis colonies to improve simultaneously all aspects of the decision-making process--i.e. speed, accuracy and cohesion--and partly circumvent the speed-accuracy trade

Ultra Fast, High Rep Rate, High Voltage Spark Gap Pulser

Science.gov (United States)

1995-07-01

current rise time. The spark gap was designed to have a coaxial geometry reducing its inductance. Provisions were made to pass flowing gas between the...ULTRA FAST, HIGH REP RATE, HIGH VOLTAGE SPARK GAP PULSER Robert A. Pastore Jr., Lawrence E. Kingsley, Kevin Fonda, Erik Lenzing Electrophysics and...Modeling Branch AMSRL-PS-EA Tel.: (908)-532-0271 FAX: (908)-542-3348 U.S. Army Research Laboratory Physical Sciences Directorate Ft. Monmouth

Spallation model for the high strain rates range

Science.gov (United States)

Dekel, E.; Eliezer, S.; Henis, Z.; Moshe, E.; Ludmirsky, A.; Goldberg, I. B.

1998-11-01

Measurements of the dynamic spall strength in aluminum and copper shocked by a high power laser to pressures of hundreds of kbars show a rapid increase in the spall strength with the strain rate at values of about 107 s-1. We suggest that this behavior is a result of a change in the spall mechanism. At low strain rates the spall is caused by the motion and coalescence of material's initial flaws. At high strain rates there is not enough time for the flaws to move and the spall is produced by the formation and coalescence of additional cavities where the interatomic forces become dominant. Material under tensile stress is in a metastable condition and cavities of a critical radius are formed in it due to thermal fluctuations. These cavities grow due to the tension. The total volume of the voids grow until the material disintegrates at the spall plane. Simplified calculations based on this model, describing the metal as a viscous liquid, give results in fairly good agreement with the experimental data and predict the increase in spall strength at high strain rates.

The Effect of Minimum Wage Rates on High School Completion

Science.gov (United States)

Warren, John Robert; Hamrock, Caitlin

2010-01-01

Does increasing the minimum wage reduce the high school completion rate? Previous research has suffered from (1. narrow time horizons, (2. potentially inadequate measures of states' high school completion rates, and (3. potentially inadequate measures of minimum wage rates. Overcoming each of these limitations, we analyze the impact of changes in…

Effect of granulocyte colony-stimulating factor on murine thymic emigration and subsets reconstitution after a sublethal dose of irradiation

International Nuclear Information System (INIS)

Zhao Hongxia; Guo Mei; Sun Xuedong; Ai Huisheng

2011-01-01

Objective: To investigate the effects of recombinant human granulocyte colony stimulating factor (G-CSF) on murine thymic emigration and subsets reconstitution after a sublethal dose of irradiation. Methods: Female BALB/c mice were irradiated with a 6.0 Gy of γ-ray total-body irradiation and then randomly divided into GCSF group and control group. For mice in the GCSF group, recombinant human G-CSF 100 μg · kg -1 · d -1 was injected subcutaneously once daily for 14 continuous days and mice in the control group were given the same volume of phosphate buffered solution (PBS). At 7, 14, 21 and 28 days later, mice were killed and thymus mononuclear cell suspension were analyzed by flow cytometry for the percentage of the four stages of thymic CD4 - CD8 - double negative cells (DN1-4) and the CD4 + CD8 + double positive ( CD4 + CD8 + DP), CD4 + CD8 - single positive (CD4 + SP), CD4 - CD8 + single positive cells (CD8 + SP).Real-time PCR was used for detection and quantitation of murine T cell receptor rearrangement excision circles (sjTRECs) of the thymic cells of 30 and 60 d after irradiation. Results: The percentage of thymic DN1 cells in GCSF group was significantly higher than that of the control group 7 d after irradiation (t=9.59, P<0.05). 21 d later, the proportion of thymic DN3 and DN4 cells were higher than those of the control group (t=16.37, 7.6, P<0.05). The percentage of thymic CD4 + CD8 + DP cells decreased 7 d after irradiation,increased at 14 d, decreased again at 21 days,and then got a permanent recover. The percentage of thymic CD4 + CD8 + DP cells in the GCSF group recovered to normal and was significantly higher than that of the control group 28 days after irradiation (t=12.22, P<0.05). The percentage of thymic CD8 + SP cells of the GCSF group was significantly higher than that of the control group 21 d after irradiation (t=3.77, P<0.05), while G-CSF had no obvious influence on the percentage of the thymic CD4 + SP cells. The sjTRECs copies in the

HIGH-RATE ANAEROBIC TREATMENT OF ALCOHOLIC WASTEWATERS

Directory of Open Access Journals (Sweden)

Florencio L.

1997-01-01

Full Text Available Modern high-rate anaerobic wastewater treatment processes are rapidly becoming popular for industrial wastewater treatment. However, until recently stable process conditions could not be guaranteed for alcoholic wastewaters containing higher concentrations of methanol. Although methanol can be directly converted into methane by methanogens, under specific conditions it can also be converted into acetate and butyrate by acetogens. The accumulation of volatile fatty acids can lead to reactor instability in a weakly buffered reactor. Since this process was insufficiently understood, the application of high-rate anaerobic reactors was highly questionable. This research investigated the environmental factors that are of importance in the predominance of methylotrophic methanogens over acetogens in a natural mixed culture during anaerobic wastewater treatment in upflow anaerobic sludge bed reactors. Technological and microbiological aspects were investigated. Additionally, the route by which methanol is converted into methane is also presented

Baltimore District Tackles High Suspension Rates

Science.gov (United States)

Maxwell, Lesli A.

2007-01-01

This article reports on how the Baltimore District tackles its high suspension rates. Driven by an increasing belief that zero-tolerance disciplinary policies are ineffective, more educators are embracing strategies that do not exclude misbehaving students from school for offenses such as insubordination, disrespect, cutting class, tardiness, and…

Cosmological Evolution of the Central Engine in High-Luminosity, High-Accretion Rate AGN

Directory of Open Access Journals (Sweden)

Matteo Guainazzi

2014-12-01

Full Text Available In this paper I discuss the status of observational studies aiming at probing the cosmological evolution of the central engine in high-luminosity, high-accretion rate Active Galactic Nuclei (AGN. X-ray spectroscopic surveys, supported by extensive multi-wavelength coverage, indicate a remarkable invariance of the accretion disk plus corona system, and of their coupling up to redshifts z≈6. Furthermore, hard X-ray (E >10 keV surveys show that nearby Seyfert Galaxies share the same central engine notwithstanding their optical classication. These results suggest that the high-luminosity, high accretion rate quasar phase of AGN evolution is homogeneous over cosmological times.

High strain rate studies in rock

International Nuclear Information System (INIS)

Grady, D.

1977-01-01

Dynamic compression studies using high velocity impact are usually considered to involve a catastrophic process of indeterminate loading rate by which a material is brough to a shock compressed state. Although this is frequently the case, methods are also available to control the rate of strain during the shock compression process. One of the most accurate of these methods makes use of the anomalous nonlinear elastic property of glass to transform an initial shock or step wave input into a ramp wave of known amplitude and duration. Fused silica is the most carefully calibrated material for this purpose and, when placed between the test specimen and the impact projectile, can provide loading strain rates in the range of 10 4 /s to 10 6 /s for final stress states of approximately 3.9 GPa or less.Ramp wave compression experiments have been conducted on dolomite at strain rates of 3 x 10 4 /s. Both initial yielding and subsequent deformation at this strain rate agrees well with previous shock wave studies (epsilon-dotapprox.10 6 /s) and differs substantially from quasi-static measurements (epsilon-dotapprox.10 -4 /s). The ramp wave studies have also uncovered a pressure-induced phase transition in dolomite initiating at 4.0 GPa

Return migration of highly skilled scientists and engineers to Morocco : return or circulation ?

OpenAIRE

Gaillard, A.M.; Gaillard, Jacques

2015-01-01

The qualification level of the emigrating Moroccans rose steadily in the 1990s, and especially since the year 2000. At present, an estimated 20 per cent of the highly qualified Moroccans live abroad. Student migration, which accounts for a large part of this 20 per cent, is contributing substantially to keeping this level high. For the last 20 years Morocco has been testing actions to mobilise and reconnect its S&T diaspora. The related special programmes and institutions are discussed and an...

Stretching of red blood cells at high strain rates

Science.gov (United States)

Mancuso, J. E.; Ristenpart, W. D.

2017-10-01

Most work on the mechanical behavior of red blood cells (RBCs) in flow has focused on simple shear flows. Relatively little work has examined RBC deformations in the physiologically important extensional flow that occurs at the entrance to a constriction. In particular, previous work suggests that RBCs rapidly stretch out and then retract upon entering the constriction, but to date no model predicts this behavior for the extremely high strain rates typically experienced there. In this Rapid Communication, we use high speed video to perform systematic measurements of the dynamic stretching behavior of RBCs as they enter a microfluidic constriction. We demonstrate that both the Kelvin-Voigt and Skalak viscoelastic models capture the observed stretching dynamics, up to strain rates as high as 2000 s-1. The results indicate that the effective elastic modulus of the RBC membrane at these strain rates is an order of magnitude larger than moduli measured by micropipette aspiration or other low strain rate techniques.

High-power pre-chirp managed amplification of femtosecond pulses at high repetition rates

International Nuclear Information System (INIS)

Liu, Yang; Li, Wenxue; Zhao, Jian; Bai, Dongbi; Luo, Daping; Zeng, Heping

2015-01-01

Femtosecond pulses at 250 MHz repetition rate from a mode-locked fiber laser are amplified to high power in a pre-chirp managed amplifier. The experimental strategy offers a potential towards high-power ultrashort laser pulses at high repetition rates. By investigating the laser pulse evolution in the amplification processes, we show that self-similar evolution, finite gain bandwidth and mode instabilities determine pulse characteristics in different regimes. Further average power scaling is limited by the mode instabilities. Nevertheless, this laser system enables us to achieve sub-50 fs pulses with an average power of 93 W. (letter)

High-frame-rate digital radiographic videography

Science.gov (United States)

King, Nicholas S. P.; Cverna, Frank H.; Albright, Kevin L.; Jaramillo, Steven A.; Yates, George J.; McDonald, Thomas E.; Flynn, Michael J.; Tashman, Scott

1994-10-01

High speed x-ray imaging can be an important tool for observing internal processes in a wide range of applications. In this paper we describe preliminary implementation of a system having the eventual goal of observing the internal dynamics of bone and joint reactions during loading. Two Los Alamos National Laboratory (LANL) gated and image intensified camera systems were used to record images from an x-ray image convertor tube to demonstrate the potential of high frame-rate digital radiographic videography in the analysis of bone and joint dynamics of the human body. Preliminary experiments were done at LANL to test the systems. Initial high frame-rate imaging (from 500 to 1000 frames/s) of a swinging pendulum mounted to the face of an X-ray image convertor tube demonstrated high contrast response and baseline sensitivity. The systems were then evaluated at the Motion Analysis Laboratory of Henry Ford Health Systems Bone and Joint Center. Imaging of a 9 inch acrylic disk with embedded lead markers rotating at approximately 1000 RPM, demonstrated the system response to a high velocity/high contrast target. By gating the P-20 phosphor image from the X-ray image convertor with a second image intensifier (II) and using a 100 microsecond wide optical gate through the second II, enough prompt light decay from the x-ray image convertor phosphor had taken place to achieve reduction of most of the motion blurring. Measurement of the marker velocity was made by using video frames acquired at 500 frames/s. The data obtained from both experiments successfully demonstrated the feasibility of the technique. Several key areas for improvement are discussed along with salient test results and experiment details.

Performance of Drift-Tube Detectors at High Counting Rates for High-Luminosity LHC Upgrades

CERN Document Server

Bittner, Bernhard; Kortner, Oliver; Kroha, Hubert; Manfredini, Alessandro; Nowak, Sebastian; Ott, Sebastian; Richter, Robert; Schwegler, Philipp; Zanzi, Daniele; Biebel, Otmar; Hertenberger, Ralf; Ruschke, Alexander; Zibell, Andre

2016-01-01

The performance of pressurized drift-tube detectors at very high background rates has been studied at the Gamma Irradiation Facility (GIF) at CERN and in an intense 20 MeV proton beam at the Munich Van-der-Graaf tandem accelerator for applications in large-area precision muon tracking at high-luminosity upgrades of the Large Hadron Collider (LHC). The ATLAS muon drifttube (MDT) chambers with 30 mm tube diameter have been designed to cope with and neutron background hit rates of up to 500 Hz/square cm. Background rates of up to 14 kHz/square cm are expected at LHC upgrades. The test results with standard MDT readout electronics show that the reduction of the drift-tube diameter to 15 mm, while leaving the operating parameters unchanged, vastly increases the rate capability well beyond the requirements. The development of new small-diameter muon drift-tube (sMDT) chambers for LHC upgrades is completed. Further improvements of tracking e?ciency and spatial resolution at high counting rates will be achieved with ...

Cheetah: A high frame rate, high resolution SWIR image camera

Science.gov (United States)

Neys, Joel; Bentell, Jonas; O'Grady, Matt; Vermeiren, Jan; Colin, Thierry; Hooylaerts, Peter; Grietens, Bob

2008-10-01

A high resolution, high frame rate InGaAs based image sensor and associated camera has been developed. The sensor and the camera are capable of recording and delivering more than 1700 full 640x512pixel frames per second. The FPA utilizes a low lag CTIA current integrator in each pixel, enabling integration times shorter than one microsecond. On-chip logics allows for four different sub windows to be read out simultaneously at even higher rates. The spectral sensitivity of the FPA is situated in the SWIR range [0.9-1.7 μm] and can be further extended into the Visible and NIR range. The Cheetah camera has max 16 GB of on-board memory to store the acquired images and transfer the data over a Gigabit Ethernet connection to the PC. The camera is also equipped with a full CameralinkTM interface to directly stream the data to a frame grabber or dedicated image processing unit. The Cheetah camera is completely under software control.

Concomitant chemoradiotherapy with high dose rate brachytherapy ...

African Journals Online (AJOL)

Concomitant chemoradiotherapy with high dose rate brachytherapy as a definitive treatment modality for locally advanced cervical cancer. T Refaat, A Elsaid, N Lotfy, K Kiel, W Small Jr, P Nickers, E Lartigau ...

High-Rate Disinfection Techniques for Combined Sewer Overflow (Proceedings Paper)

Science.gov (United States)

This paper presents high-rate disinfection technologies for combined sewer overflow (CSO). The high-rate disinfection technologies of interest are: chlorination/dechlorination, ultraviolet light irradiation (UV), chlorine dioxide (ClO2 ), ozone (O3), peracetic acid (CH3COOOH ), a...

Israeli Infotech Migrants in Silicon Valley

Directory of Open Access Journals (Sweden)

Steven J. Gold

2018-01-01

Full Text Available Prior to the 1980s, Israel’s national ideology discouraged emigration and entrepreneurship among its citizens. Yet, by the late 1990s, Israeli emigrants were one of the leading immigrant nationalities in Silicon Valley. Drawing on interviews, fieldwork, a literature review, and perusal of social media, I explore the origins of Israeli involvement in high-tech activities and the extensive linkages between Israeli emigrants and the Israeli high-tech industry. I also summarize the patterns of communal cooperation that permit emigrant families to maintain an Israel-oriented way of life in suburban communities south of San Francisco, and I compare these patterns with those of Indians, a nationality engaged in the same pursuit. I conclude by considering the impact of infotech involvement on Israeli immigrants and on the U.S. economy.

Use of Fatty Acid Analysis to Determine Dispersal of Caspian Terns in the Columbia River Basin, U.S.A.

Science.gov (United States)

Maranto, C.J.; Parrish, J.K.; Herman, D.P.; Punt, A.E.; Olden, J.D.; Brett, M.T.; Roby, D.D.

2011-01-01

Lethal control, which has been used to reduce local abundances of animals in conflict with humans or with endangered species, may not achieve management goals if animal movement is not considered. In populations with emigration and immigration, lethal control may induce compensatory immigration, if the source of attraction remains unchanged. Within the Columbia River Basin (Washington, U.S.A.), avian predators forage at dams because dams tend to reduce rates of emigration of juvenile salmonids (Oncorhynchus spp.), artificially concentrating these prey. We used differences in fatty acid profiles between Caspian Terns (Hydroprogne caspia) at coastal and inland breeding colonies and terns culled by a lethal control program at a mid-Columbia River dam to infer dispersal patterns. We modeled the rate of loss of fatty acid biomarkers, which are fatty acids that can be traced to a single prey species or groups of species, to infer whether and when terns foraging at dams had emigrated from the coast. Nonmetric multidimensional scaling showed that coastal terns had high levels of C20 and C22 monounsaturated fatty acids, whereas fatty acids of inland breeders were high in C18:3n3, C20:4n6, and C22:5n3. Models of the rate of loss of fatty acid showed that approximately 60% of the terns collected at Rock Island Dam were unlikely to have bred successfully at local (inland) sites, suggesting that terns foraging at dams come from an extensive area. Fatty acid biomarkers may provide accurate information about patterns of dispersal in animal populations and may be extremely valuable in cases where populations differ demonstrably in prey base. ??2011 Society for Conservation Biology.

Physical nature of strain rate sensitivity of metals and alloys at high strain rates

Science.gov (United States)

Borodin, E. N.; Gruzdkov, A. A.; Mayer, A. E.; Selyutina, N. S.

2018-04-01

The role of instabilities of plastic flow at plastic deformation of various materials is one of the important cross-disciplinary problems which is equally important in physics, mechanics and material science. The strain rate sensitivities under slow and high strain rate conditions of loading have different physical nature. In the case of low strain rate, the sensitivity arising from the inertness of the defect structures evolution can be expressed by a single parameter characterizing the plasticity mechanism. In our approach, this is the value of the characteristic relaxation time. In the dynamic case, there are additional effects of “high-speed sensitivity” associated with the micro-localization of the plastic flow near the stress concentrators. In the frames of mechanical description, this requires to introduce additional strain rate sensitivity parameters, which is realized in numerous modifications of Johnson–Cook and Zerilli–Armstrong models. The consideration of both these factors is fundamental for an adequate description of the problems of dynamic deformation of highly inhomogeneous metallic materials such as steels and alloys. The measurement of the dispersion of particle velocities on the free surface of a shock-loaded material can be regarded as an experimental expression of the effect of micro-localization. This is also confirmed by our results of numerical simulation of the propagation of shock waves in a two-dimensional formulation and analytical estimations.

Radiobiological aspects of continuous low dose-rate irradiation and fractionated high dose-rate irradiation

International Nuclear Information System (INIS)

Turesson, I.

1990-01-01

The biological effects of continuous low dose-rate irradiation and fractionated high dose-rate irradiation in interstitial and intracavitary radiotherapy and total body irradiation are discussed in terms of dose-rate fractionation sensitivity for various tissues. A scaling between dose-rate and fraction size was established for acute and late normal-tissue effects which can serve as a guideline for local treatment in the range of dose rates between 0.02 and 0.005 Gy/min and fraction sizes between 8.5 and 2.5 Gy. This is valid provided cell-cycle progression and proliferation can be ignored. Assuming that the acute and late tissue responses are characterized by α/β values of about 10 and 3 Gy and a mono-exponential repair half-time of about 3 h, the same total doses given with either of the two methods are approximately equivalent. The equivalence for acute and late non-hemopoietic normal tissue damage is 0.02 Gy/min and 8.5 Gy per fraction; 0.01 Gy/min and 5.5 Gy per fraction; and 0.005 Gy/min and 2.5Gy per fraction. A very low dose rate, below 0.005 Gy/min, is thus necessary to simulate high dose-rate radiotherapy with fraction sizes of about 2Gy. The scaling factor is, however, dependent on the repair half-time of the tissue. A review of published data on dose-rate effects for normal tissue response showed a significantly stronger dose-rate dependence for late than for acute effects below 0.02 Gy/min. There was no significant difference in dose-rate dependence between various acute non-hemopoietic effects or between various late effects. The consistent dose-rate dependence, which justifies the use of a general scaling factor between fraction size and dose rate, contrasts with the wide range of values for repair half-time calculated for various normal-tissue effects. This indicates that the model currently used for repair kinetics is not satisfactory. There are also few experimental data in the clinical dose-rate range, below 0.02 Gy/min. It is therefore

Investigation of high-rate lithium-thionyl chloride cells

Science.gov (United States)

Hayes, Catherine A.; Gust, Steven; Farrington, Michael D.; Lockwood, Judith A.; Donaldson, George J.

Chemical analysis of a commercially produced high-rate D-size lithium-thionyl cell was carried out, as a function of rate of discharge (1 ohm and 5 ohms), depth of discharge, and temperature (25 C and -40 C), using specially developed methods for identifying suspected minor cell products or impurities which may effect cell performance. These methods include a product-retrieval system which involves solvent extraction to enhance the recovery of suspected semivolatile minor chemicals, and methods of quantitative GC analysis of volatile and semivolatile products. The nonvolatile products were analyzed by wet chemical methods. The results of the analyses indicate that the predominant discharge reaction in this cell is 4Li + 2SOCl2 going to 4LiCl + S + SO2, with SO2 formation decreasing towards the end of cell life (7 to 12 Ah). The rate of discharge had no effect on the product distribution. Upon discharge of the high-rate cell at -40 C, one cell exploded, and all others exhibited overheating and rapid internal pressure rise when allowed to warm up to room temperature.

High throughput route selection in multi-rate wireless mesh networks

Institute of Scientific and Technical Information of China (English)

WEI Yi-fei; GUO Xiang-li; SONG Mei; SONG Jun-de

2008-01-01

Most existing Ad-hoc routing protocols use the shortest path algorithm with a hop count metric to select paths. It is appropriate in single-rate wireless networks, but has a tendency to select paths containing long-distance links that have low data rates and reduced reliability in multi-rate networks. This article introduces a high throughput routing algorithm utilizing the multi-rate capability and some mesh characteristics in wireless fidelity (WiFi) mesh networks. It uses the medium access control (MAC) transmission time as the routing metric, which is estimated by the information passed up from the physical layer. When the proposed algorithm is adopted, the Ad-hoc on-demand distance vector (AODV) routing can be improved as high throughput AODV (HT-AODV). Simulation results show that HT-AODV is capable of establishing a route that has high data-rate, short end-to-end delay and great network throughput.

Quantum Communication with a High-Rate Entangled Photon Source

Science.gov (United States)

Wilson, Nathaniel C.; Chaffee, Dalton W.; Lekki, John D.; Wilson, Jeffrey D.

2016-01-01

A high generation rate photon-pair source using a dual element periodically-poled potassium titanyl phosphate (PP KTP) waveguide is described. The photon-pair source features a high pair generation rate, a compact power-efficient package, and continuous wave (CW) or pulsed operation. Characterization and test results are presented. Details and preliminary results of a laboratory free-space QKD experiment with the B92 protocol are also presented.

High-Rate Data-Capture for an Airborne Lidar System

Science.gov (United States)

Valett, Susan; Hicks, Edward; Dabney, Philip; Harding, David

2012-01-01

A high-rate data system was required to capture the data for an airborne lidar system. A data system was developed that achieved up to 22 million (64-bit) events per second sustained data rate (1408 million bits per second), as well as short bursts (less than 4 s) at higher rates. All hardware used for the system was off the shelf, but carefully selected to achieve these rates. The system was used to capture laser fire, single-photon detection, and GPS data for the Slope Imaging Multi-polarization Photo-counting Lidar (SIMPL). However, the system has applications for other laser altimeter systems (waveform-recording), mass spectroscopy, xray radiometry imaging, high-background- rate ranging lidar, and other similar areas where very high-speed data capture is needed. The data capture software was used for the SIMPL instrument that employs a micropulse, single-photon ranging measurement approach and has 16 data channels. The detected single photons are from two sources those reflected from the target and solar background photons. The instrument is non-gated, so background photons are acquired for a range window of 13 km and can comprise many times the number of target photons. The highest background rate occurs when the atmosphere is clear, the Sun is high, and the target is a highly reflective surface such as snow. Under these conditions, the total data rate for the 16 channels combined is expected to be approximately 22 million events per second. For each photon detection event, the data capture software reads the relative time of receipt, with respect to a one-per-second absolute time pulse from a GPS receiver, from an event timer card with 0.1-ns precision, and records that information to a RAID (Redundant Array of Independent Disks) storage device. The relative time of laser pulse firings must also be read and recorded with the same precision. Each of the four event timer cards handles the throughput from four of the channels. For each detection event, a flag is

Yield strength of molybdenum, tantalum and tungsten at high strain rates and very high temperatures

International Nuclear Information System (INIS)

Škoro, G.P.; Bennett, J.R.J.; Edgecock, T.R.; Booth, C.N.

2012-01-01

Highlights: ► New experimental data on the yield strength of molybdenum, tantalum and tungsten. ► High strain rate effects at record high temperatures (up to 2700 K). ► Test of the consistency of the Zerilli–Armstrong model at very high temperatures. - Abstract: Recently reported results of the high strain rate, high temperature measurements of the yield strength of tantalum and tungsten have been analyzed along with new experimental results on the yield strength of molybdenum. Thin wires are subjected to high stress by passing a short, fast, high current pulse through a thin wire; the amplitude of the current governs the stress and the repetition rate of the pulses determines the temperature of the wire. The highest temperatures reached in the experiments were 2100 °C (for molybdenum), 2250 °C (for tantalum) and 2450 °C (for tungsten). The strain-rates in the tests were in the range from 500 to 1500 s −1 . The parameters for the constitutive equation developed by Zerilli and Armstrong have been determined from the experimental data and the results have been compared with the data obtained at lower temperatures. An exceptionally good fit is obtained for the deformation of tungsten.

Curt Teichert - Dokumente zu einer Emigration (Dänemark - Australien - USA)

Science.gov (United States)

Seibold, Eugen; Seibold, Ilse

2008-05-01

Curt Teichert (Königsberg 1905—Arlington, Virginia 1996) provides in his life story examples of the many hardships and difficulties encountered by emigrants who were fortunate to escape Hitleŕs regime. He was a great paleontologist and stratigrapher whose fieldwork on four continents involved nearly every fossil group; his interests were focussed mainly on the Paleozoic and the Triassic. His results and critical remarks on many general topics filled numerous publications. Remarkably, he accomplished all this under partly very unfavorable working conditions. He donated his scientific correspondence from his times in Germany, Denmark and Australia to the Geological Archive in Freiburg. The following article makes use of these documents. Teichert’s professional career started in Germany in the scientifically exciting nineteen-twenties; he worked at the universities in Königsberg, Munich and Freiburg/Breisgau. In Freiburg, however, he had serious disagreements with the Director of the Geological Institute there—this in spite of his investigations having produced some excellent results. The times around 1930 were a period of a global economic crisis, and, like many others, he could only survive financially by getting fellowships from different institutions and payments for publications. In 1933, his situation in Germany became even more critical: this was because he had married a “Non-Aryan”. However, he was able to work in Copenhagen from the end of 1933; this was largely a result of his having participated in 1931 1932 in an expedition to Greenland led by the Dane Lauge Koch. Unfortunately, he could not get a permanent position in Copenhagen because the relations between him and the influential Koch became very unpleasant. Noting Hitleŕs war preparation, Teichert tried to escape from Europe. He wrote many touching letters to correspondents around the globe, receiving mostly disappointing answers. Finally, in 1937, he succeeded in getting the post of a

High production rate of IBAD-MgO buffered substrate

Energy Technology Data Exchange (ETDEWEB)

Yoshizumi, M., E-mail: myoshizumi@istec.or.j [Superconductivity Research Laboratory, ISTEC, Shinonome 1-10-13, Koto-ku, Tokyo 135-0062 (Japan); Miyata, S.; Ibi, A.; Fukushima, H.; Yamada, Y.; Izumi, T.; Shiohara, Y. [Superconductivity Research Laboratory, ISTEC, Shinonome 1-10-13, Koto-ku, Tokyo 135-0062 (Japan)

2009-10-15

The conventional IBAD (Ion Beam Assisted Deposition) process using fluorite materials yields low production rates, resulting in high production cost, which reduces the motivation for practical application in spite of its high quality. The IBAD process using rock salt materials, e.g. MgO, is well known as a strong candidate of practical application due to its potential of high production rate and high in-plane grain alignment. In this work, the IBAD-MgO process was investigated for a newly developed architecture of PLD (Pulsed Laser Deposition)-CeO{sub 2}/sputter-LMO (LaMnO{sub 3})/IBAD-MgO/sputter-GZO (Gd{sub 2}Zr{sub 2}O{sub 7})/Hastelloy{sup TM} to make long buffered metal tapes with high properties and a high production rate. The 50 m-long IBAD-MgO substrates with about 4 deg. of DELTAphiCeO{sub 2} in an XRD phi scan could be fabricated repeatedly. A GdBCO (GdBa{sub 2}Cu{sub 3}O{sub x}) layer deposited on the buffered substrate showed the minimum I{sub c} value of 325 A/cm-w in a 41 m-long tape. Almost of the tape showed 500-600 A/cm-w of I{sub c} value. The deposition time for the IBAD-MgO layer was 60 s which was about 2 orders of magnitude shorter than the conventional IBAD process. The production rate of 24 m/h was realized at the IBAD-MgO process to fabricate the GdBCO coated conductor with high J{sub c} and I{sub c} properties.

High Dose-Rate Versus Low Dose-Rate Brachytherapy for Lip Cancer

Energy Technology Data Exchange (ETDEWEB)

Ghadjar, Pirus, E-mail: pirus.ghadjar@insel.ch [Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern (Switzerland); Bojaxhiu, Beat [Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern (Switzerland); Simcock, Mathew [Swiss Group for Clinical Cancer Research Coordinating Center, Bern (Switzerland); Terribilini, Dario; Isaak, Bernhard [Division of Medical Radiation Physics, Inselspital, Bern University Hospital, and University of Bern, Bern (Switzerland); Gut, Philipp; Wolfensberger, Patrick; Broemme, Jens O.; Geretschlaeger, Andreas; Behrensmeier, Frank; Pica, Alessia; Aebersold, Daniel M. [Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern (Switzerland)

2012-07-15

Purpose: To analyze the outcome after low-dose-rate (LDR) or high-dose-rate (HDR) brachytherapy for lip cancer. Methods and Materials: One hundred and three patients with newly diagnosed squamous cell carcinoma of the lip were treated between March 1985 and June 2009 either by HDR (n = 33) or LDR brachytherapy (n = 70). Sixty-eight patients received brachytherapy alone, and 35 received tumor excision followed by brachytherapy because of positive resection margins. Acute and late toxicity was assessed according to the Common Terminology Criteria for Adverse Events 3.0. Results: Median follow-up was 3.1 years (range, 0.3-23 years). Clinical and pathological variables did not differ significantly between groups. At 5 years, local recurrence-free survival, regional recurrence-free survival, and overall survival rates were 93%, 90%, and 77%. There was no significant difference for these endpoints when HDR was compared with LDR brachytherapy. Forty-two of 103 patients (41%) experienced acute Grade 2 and 57 of 103 patients (55%) experienced acute Grade 3 toxicity. Late Grade 1 toxicity was experienced by 34 of 103 patients (33%), and 5 of 103 patients (5%) experienced late Grade 2 toxicity; no Grade 3 late toxicity was observed. Acute and late toxicity rates were not significantly different between HDR and LDR brachytherapy. Conclusions: As treatment for lip cancer, HDR and LDR brachytherapy have comparable locoregional control and acute and late toxicity rates. HDR brachytherapy for lip cancer seems to be an effective treatment with acceptable toxicity.

Mechanical characterization of alloys in extreme conditions of high strain rates and high temperature

Science.gov (United States)

Cadoni, Ezio

2018-03-01

The aim of this paper is the description of the mechanical characterization of alloys under extreme conditions of temperature and loading. In fact, in the frame of the Cost Action CA15102 “Solutions for Critical Raw Materials Under Extreme Conditions (CRM-EXTREME)” this aspect is crucial and many industrial applications have to consider the dynamic response of materials. Indeed, for a reduction and substitution of CRMs in alloys is necessary to design the materials and understand if the new materials behave better or if the substitution or reduction badly affect their performance. For this reason, a deep knowledge of the mechanical behaviour at high strain-rates of considered materials is required. In general, machinery manufacturing industry or transport industry as well as energy industry have important dynamic phenomena that are simultaneously affected by extended strain, high strain-rate, damage and pressure, as well as conspicuous temperature gradients. The experimental results in extreme conditions of high strain rate and high temperature of an austenitic stainless steel as well as a high-chromium tempered martensitic reduced activation steel Eurofer97 are presented.

Electrophoretic Deposition of Gallium with High Deposition Rate

Directory of Open Access Journals (Sweden)

Hanfei Zhang

2014-12-01

Full Text Available In this work, electrophoretic deposition (EPD is reported to form gallium thin film with high deposition rate and low cost while avoiding the highly toxic chemicals typically used in electroplating. A maximum deposition rate of ~0.6 μm/min, almost one order of magnitude higher than the typical value reported for electroplating, is obtained when employing a set of proper deposition parameters. The thickness of the film is shown to increase with deposition time when sequential deposition is employed. The concentration of Mg(NO32, the charging salt, is also found to be a critical factor to control the deposition rate. Various gallium micropatterns are obtained by masking the substrate during the process, demonstrating process compatibility with microfabrication. The reported novel approach can potentially be employed in a broad range of applications with Ga as a raw material, including microelectronics, photovoltaic cells, and flexible liquid metal microelectrodes.

High strain-rate soft material characterization via inertial cavitation

Science.gov (United States)

Estrada, Jonathan B.; Barajas, Carlos; Henann, David L.; Johnsen, Eric; Franck, Christian

2018-03-01

Mechanical characterization of soft materials at high strain-rates is challenging due to their high compliance, slow wave speeds, and non-linear viscoelasticity. Yet, knowledge of their material behavior is paramount across a spectrum of biological and engineering applications from minimizing tissue damage in ultrasound and laser surgeries to diagnosing and mitigating impact injuries. To address this significant experimental hurdle and the need to accurately measure the viscoelastic properties of soft materials at high strain-rates (103-108 s-1), we present a minimally invasive, local 3D microrheology technique based on inertial microcavitation. By combining high-speed time-lapse imaging with an appropriate theoretical cavitation framework, we demonstrate that this technique has the capability to accurately determine the general viscoelastic material properties of soft matter as compliant as a few kilopascals. Similar to commercial characterization algorithms, we provide the user with significant flexibility in evaluating several constitutive laws to determine the most appropriate physical model for the material under investigation. Given its straightforward implementation into most current microscopy setups, we anticipate that this technique can be easily adopted by anyone interested in characterizing soft material properties at high loading rates including hydrogels, tissues and various polymeric specimens.

Electronics for very high rate tracking detectors

International Nuclear Information System (INIS)

Williams, H.H.; Dressnandt, N.; Ekenberg, T.; Gerds, E.J.; Newcomer, F.M.; Tedja, S.; Van Berg, R.; Van der Speigel, J.

1995-01-01

Results are presented on a system of electronics designed for very high rate tracking detectors at the SSC and LHC. The primary goal was a system for signal detection, time measurement, and readout for the straw tracker for SDC. An integrated circuit incorporating eight channels of amplifier-shaper-discriminator (including detector tail cancellation), and two different integrated circuits for time measurement are described. The performance of tracking measurements up to counting rates of 8 MHz per wire is reported, as well as preliminary results from a baseline restoration circuit. (orig.)

High rate spectroscopy for on-line nuclear coal analyzer (Nucoalyzer)

International Nuclear Information System (INIS)

McQuaid, J.H.; Brown, D.R.; Gozani, T.; Bozorgmanesh, H.

1980-01-01

A high count rate, time-variant Ge(Li) spectrometer has been developed for on-line coal analysis. The analyzer is being fabricated for use in a power generating station. Prompt neutron activation of coal samples is the basis of analysis, with 252 Cf as the source for irradiation. The spectroscopy system allows counting rates up to 150 k counts per second without significant loss in energy resolution or peak shape. The high data throughput allows the coal analyzer to be used for on-line process control. The coal analyzer will be discussed, with emphasis on the high-rate signal processing system. Results of analysis of coal samples will be presented

High counting rate resistive-plate chamber

International Nuclear Information System (INIS)

Peskov, V.; Anderson, D.F.; Kwan, S.

1993-05-01

Parallel-plate avalanche chambers (PPAC) are widely used in physics experiments because they are fast ( 5 counts/mm 2 . A resistive-plate chamber (RPC) is similar to the PPAC in construction except that one or both of the electrodes are made from high resistivity (≥10 10 Ω·cm) materials. In practice RPCs are usually used in the spark mode. Resistive electrodes are charged by sparks, locally reducing the actual electric field in the gap. The size of the charged surface is about 10 mm 2 , leaving the rest of the detector unaffected. Therefore, the rate capability of such detectors in the spark mode is considerably higher than conventional spark counters. Among the different glasses tested the best results were obtained with electron type conductive glasses, which obey Ohm's law. Most of the work with such glasses was done with high pressure parallel-plate chambers (10 atm) for time-of-flight measurements. Resistive glasses have been expensive and produced only in small quantities. Now resistive glasses are commercially available, although they are still expensive in small scale production. From the positive experience of different groups working with the resistive glasses, it was decided to review the old idea to use this glass for the RPC. This work has investigated the possibility of using the RPC at 1 atm and in the avalanche mode. This has several advantages: simplicity of construction, high rate capability, low voltage operation, and the ability to work with non-flammable gases

Microstructural evolution at high strain rates in solution-hardened interstitial free steels

International Nuclear Information System (INIS)

Uenishi, A.; Teodosiu, C.; Nesterova, E.V.

2005-01-01

Comprehensive transmission electron microscopical studies have been conducted for solution-hardened steels deformed at high (1000 s -1 ) and low (0.001 s -1 ) strain rates, in order to clarify the effects of strain rate and a jump in strain rate on the evolution of the microstructure and its connection with the mechanical response. It was revealed that the various types of microstructure, observed even within the same specimen, depend on the corresponding grain orientations and their evolution with progressive deformation depends on these microstructure types. At high strain rates, the dislocation density increases especially at low strains and the onset of dislocation organization is delayed. A jump in strain rate causes an increase of the dislocation density inside an organized structure. These results corroborated the mechanical behaviour at high strain rates after compensation for the cross-sectional reduction and temperature increase. The higher work-hardening rate at high strain rates could be connected to a delay in the dislocation organization. The high work-hardening rate just after a jump could be due to an increase of the density of dislocations distributed uniformly inside an organized structure

Delayed high school start times later than 8:30am and impact on graduation rates and attendance rates.

Science.gov (United States)

McKeever, Pamela Malaspina; Clark, Linda

2017-04-01

The first purpose of this study was to investigate changes in high school graduation rates with a delayed school start time of later than 8:30am. The second aim of the study was to analyze the association between a delayed high school start time later than 8:30am and attendance rates. In the current study, a pre-post design using a repeated-measures analysis of variance was used to examine changes in attendance and graduation rates 2 years after a delayed start was implemented. Public high schools from 8 school districts (n=29 high schools) located throughout 7 different states. Schools were identified using previous research from the Children's National Medical Center's Division of Sleep Medicine Research Team. A total membership of more than 30,000 high school students enrolled in the 29 schools identified by the Children's National Medical Center's Research Team. A pre-post design was used for a within-subject design, controlling for any school-to-school difference in the calculation of the response variable. This is the recommended technique for a study that may include data with potential measurement error. Findings from this study linked a start time of later than 8:30am to improved attendance rates and graduation rates. Attendance rates and graduation rates significantly improved in schools with delayed start times of 8:30am or later. School officials need to take special notice that this investigation also raises questions about whether later start times are a mechanism for closing the achievement gap due to improved graduation rates. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

High Dose-Rate Versus Low Dose-Rate Brachytherapy for Lip Cancer

International Nuclear Information System (INIS)

Ghadjar, Pirus; Bojaxhiu, Beat; Simcock, Mathew; Terribilini, Dario; Isaak, Bernhard; Gut, Philipp; Wolfensberger, Patrick; Brömme, Jens O.; Geretschläger, Andreas; Behrensmeier, Frank; Pica, Alessia; Aebersold, Daniel M.

2012-01-01

Purpose: To analyze the outcome after low-dose-rate (LDR) or high-dose-rate (HDR) brachytherapy for lip cancer. Methods and Materials: One hundred and three patients with newly diagnosed squamous cell carcinoma of the lip were treated between March 1985 and June 2009 either by HDR (n = 33) or LDR brachytherapy (n = 70). Sixty-eight patients received brachytherapy alone, and 35 received tumor excision followed by brachytherapy because of positive resection margins. Acute and late toxicity was assessed according to the Common Terminology Criteria for Adverse Events 3.0. Results: Median follow-up was 3.1 years (range, 0.3–23 years). Clinical and pathological variables did not differ significantly between groups. At 5 years, local recurrence-free survival, regional recurrence-free survival, and overall survival rates were 93%, 90%, and 77%. There was no significant difference for these endpoints when HDR was compared with LDR brachytherapy. Forty-two of 103 patients (41%) experienced acute Grade 2 and 57 of 103 patients (55%) experienced acute Grade 3 toxicity. Late Grade 1 toxicity was experienced by 34 of 103 patients (33%), and 5 of 103 patients (5%) experienced late Grade 2 toxicity; no Grade 3 late toxicity was observed. Acute and late toxicity rates were not significantly different between HDR and LDR brachytherapy. Conclusions: As treatment for lip cancer, HDR and LDR brachytherapy have comparable locoregional control and acute and late toxicity rates. HDR brachytherapy for lip cancer seems to be an effective treatment with acceptable toxicity.

Increased strength of concrete subject to high loading rates

International Nuclear Information System (INIS)

Curbach, M.

1987-01-01

Within the scope of this work various problems are discussed which occur in connection with concrete under high tensile loading rates (e.g. when a plane crashes on a nuclear power plant very high loads occur which act only for a very short time). Particularly the causes for the already frequently noticed increases in strength with increasing loading rates are investigated and also the question whether this increased strength can be taken into account when dimensioning a construction. (MM) [de

Authoritative School Climate and High School Dropout Rates

Science.gov (United States)

Jia, Yuane; Konold, Timothy R.; Cornell, Dewey

2016-01-01

This study tested the association between school-wide measures of an authoritative school climate and high school dropout rates in a statewide sample of 315 high schools. Regression models at the school level of analysis used teacher and student measures of disciplinary structure, student support, and academic expectations to predict overall high…

Consistent high clinical pregnancy rates and low ovarian hyperstimulation syndrome rates in high-risk patients after GnRH agonist triggering and modified luteal support

DEFF Research Database (Denmark)

Iliodromiti, Stamatina; Blockeel, Christophe; Tremellen, Kelton P

2013-01-01

Are clinical pregnancy rates satisfactory and the incidence of OHSS low after GnRH agonist trigger and modified intensive luteal support in patients with a high risk of ovarian hyperstimulation syndrome (OHSS)?......Are clinical pregnancy rates satisfactory and the incidence of OHSS low after GnRH agonist trigger and modified intensive luteal support in patients with a high risk of ovarian hyperstimulation syndrome (OHSS)?...

Video-rate or high-precision: a flexible range imaging camera

Science.gov (United States)

Dorrington, Adrian A.; Cree, Michael J.; Carnegie, Dale A.; Payne, Andrew D.; Conroy, Richard M.; Godbaz, John P.; Jongenelen, Adrian P. P.

2008-02-01

A range imaging camera produces an output similar to a digital photograph, but every pixel in the image contains distance information as well as intensity. This is useful for measuring the shape, size and location of objects in a scene, hence is well suited to certain machine vision applications. Previously we demonstrated a heterodyne range imaging system operating in a relatively high resolution (512-by-512) pixels and high precision (0.4 mm best case) configuration, but with a slow measurement rate (one every 10 s). Although this high precision range imaging is useful for some applications, the low acquisition speed is limiting in many situations. The system's frame rate and length of acquisition is fully configurable in software, which means the measurement rate can be increased by compromising precision and image resolution. In this paper we demonstrate the flexibility of our range imaging system by showing examples of high precision ranging at slow acquisition speeds and video-rate ranging with reduced ranging precision and image resolution. We also show that the heterodyne approach and the use of more than four samples per beat cycle provides better linearity than the traditional homodyne quadrature detection approach. Finally, we comment on practical issues of frame rate and beat signal frequency selection.

Italia: La chiusura della Casa dell’Emigrante come spunto riflessione sui rientri degli emigrati italiani

OpenAIRE

Aluffi Pentini, Anna; Olivieri, Fabio

2009-01-01

In the literature on migration, as well as in social policies regarding this phenomenon, the situation of returning emigrants receives scant attention. This essay establishes an intricate connection between attitudes and policies that prevail in a country regarding emigration and those concerning immigration. The case of Italy provides a prime example for this as it once was a classical country of emigration, only to turn, in recent decades, into a country that appears highly attractive (and ...

High-rate operant behavior in two mouse strains: a response-bout analysis.

Science.gov (United States)

Johnson, Joshua E; Pesek, Erin F; Newland, M Christopher

2009-06-01

Operant behavior sometimes occurs in bouts characterized by an initiation rate, within-bout response rate, and bout length. The generality of this structure was tested using high-rate nose-poking in mice. Reinforcement of short interresponse times produced high response rates while a random-interval schedule held reinforcement rates constant. BALB/c mice produced bouts that were more frequent, longer, and contained a higher within-bout rate of responding (nine nose-pokes/s) than did the C57BL/6 mice (five nose-pokes/s). Adding a running wheel decreased total nose-pokes and bout length, and increased bout-initiation rate. Free-feeding reduced nose-poking by decreasing bout-initiation rate. Photoperiod reversal decreased bout-initiation rate but not total nose-poke rate. Despite strain differences in bout structure, both strains responded similarly to the interventions. The three bout measures were correlated with overall rate but not with each other. Log-survival analyses provided independent descriptors of the structure of high-rate responding in these two strains.

High-rate, High Temperature Acetotrophic Methanogenesis Governed by a Three Population Consortium in Anaerobic Bioreactors

OpenAIRE

Ho, Dang; Jensen, Paul; Gutierrez-Zamora, Maria-Luisa; Beckmann, Sabrina; Manefield, Mike; Batstone, Damien

2016-01-01

A combination of acetate oxidation and acetoclastic methanogenesis has been previously identified to enable high-rate methanogenesis at high temperatures (55 to 65°C), but this capability had not been linked to any key organisms. This study combined RNA-stable isotope probing on 13C-labelled acetate and 16S amplicon sequencing to identify the active micro-organisms involved in high-rate methanogenesis. Active biomass was harvested from three bench-scale thermophilic bioreactors treating waste...

Generation of µW level plateau harmonics at high repetition rate.

Science.gov (United States)

Hädrich, S; Krebs, M; Rothhardt, J; Carstens, H; Demmler, S; Limpert, J; Tünnermann, A

2011-09-26

The process of high harmonic generation allows for coherent transfer of infrared laser light to the extreme ultraviolet spectral range opening a variety of applications. The low conversion efficiency of this process calls for optimization or higher repetition rate intense ultrashort pulse lasers. Here we present state-of-the-art fiber laser systems for the generation of high harmonics up to 1 MHz repetition rate. We perform measurements of the average power with a calibrated spectrometer and achieved µW harmonics between 45 nm and 61 nm (H23-H17) at a repetition rate of 50 kHz. Additionally, we show the potential for few-cycle pulses at high average power and repetition rate that may enable water-window harmonics at unprecedented repetition rate. © 2011 Optical Society of America

Effectiveness of high interest rate policy on exchange rates: A reexamination of the Asian financial crisis

Directory of Open Access Journals (Sweden)

Chin Diew Lai

2006-09-01

Full Text Available One of the most controversial issues in the aftermath of the Asian financial crisis has been the appropriate response of monetary policy to a sharp decline in the value of some currencies. In this paper, we empirically examine the effects on Asian exchange rates of sharply higher interest rates during the Asian financial crisis. Taking account of the currency contagion effect, our results indicate that sharply higher interest rates helped to support the exchange rates of South Korea, the Philippines, and Thailand. For Malaysia, no significant causal relation is found from the rate of interest to exchange rates, as the authorities in Malaysia did not actively adopt a high interest rate policy to defend the currency.

High repetition rate, high energy, actively Q-switched all-in-fiber laser

Science.gov (United States)

Lecourt, J. B.; Bertrand, A.; Guillemet, S.; Hernandez, Y.; Giannone, D.

2010-05-01

We report an actively Q-switched Ytterbium-doped all-in-fibre laser delivering 10ns pulses with high repetition rate (from 100kHz to 1MHz). The laser operation has been validated at three different wavelengths (1040, 1050 and 1064nm). The laser can deliver up to 20Watts average power with an high beam quality (M2 = 1).

Radiative recombination of highly charged ions: Enhanced rates at low energies

International Nuclear Information System (INIS)

Frank, A.; Mueller, A.; Haselbauer, J.; Schennach, S.; Spies, W.; Uwira, O.; Wagner, M.

1992-01-01

In a single-pass merged-beams experiment employing a dense cold electron target recombination of highly charged ions is studied. Unexpected high recombination rates are observed at low energies E cm in the electron-ion center-of-mass frame. In particular, theoretical estimates for radiative recombination are dramatically exceeded by the experimental recombination rates at E cm =0 eV for U 28+ and for Au 25+ ions. Considerable rate enhancement is also observed for Ar 15+ . This points to a general phenomenon which has to be interpreted as a consequence of high electron densities, low electron beam temperatures, high ion charge states and presence of strong magnetic fields. (orig.)

Miniaturized Stretchable and High-Rate Linear Supercapacitors

Science.gov (United States)

Zhu, Wenjun; Zhang, Yang; Zhou, Xiaoshuang; Xu, Jiang; Liu, Zunfeng; Yuan, Ningyi; Ding, Jianning

2017-07-01

Linear stretchable supercapacitors have attracted much attention because they are well suited to applications in the rapidly expanding field of wearable electronics. However, poor conductivity of the electrode material, which limits the transfer of electrons in the axial direction of the linear supercapacitors, leads to a serious loss of capacity at high rates. To solve this problem, we use gold nanoparticles to decorate aligned multiwall carbon nanotube to fabricate stretchable linear electrodes. Furthermore, we have developed fine stretchable linear supercapacitors, which exhibited an extremely high elasticity up to 400% strain with a high capacitance of about 8.7 F g-1 at the discharge current of 1 A g-1.

How Did Successful High Schools Improve Their Graduation Rates?

Science.gov (United States)

Robertson, Janna Siegel; Smith, Robert W.; Rinka, Jason

2016-01-01

The researchers surveyed 23 North Carolina high schools that had markedly improved their graduation rates over the past five years. The administrators reported on the dropout prevention practices and programs to which they attributed their improved graduation rates. The majority of schools reported policy changes, especially with suspension. The…

Guinean Population Emigrant to Spain Has Very Little Awareness of the Donation and Transplantation of Organs.

Science.gov (United States)

Ríos, A; Carrillo, J; López-Navas, A I; Martínez-Alarcón, L; Ayala, M A; Garrido, G; Ramis, G; Hernández, A M; Ramírez, P; Parrilla, P

2018-03-01

The Guinean population is an emerging group in Europe, but the group's awareness of organ donation and transplantation has not been studied. To analyze the attitude toward organ donation among the population born in Guinea living in Spain. The population older than 15 years, born in Guinea, and resident in Spain was studied, stratified by age and sex, according to census data and immigrant assistance associations. The valuation tool used was the attitude questionnaire toward organ donation PCID-DTO RIOS (questionnaire on "Donor International Collaborative Project" on organ donation and transplantation developed by Dr Ríos). A random selection of people to survey was based on stratification. Support from African immigration support associations was needed to advise on the location of potential respondents. The completion was anonymous and self-administered. A descriptive statistic was performed, and Student t, χ 2 , and Fisher tests and a logistic regression analysis were applied. In all, 181 Guineans were surveyed, of whom 32% (n = 58) were in favor of the donation of their own organs after death, 32% (n = 57) were against, and 36% (n = 66) were undecided. The variables that are associated with attitude toward donation are separated mainly into 4 large groups (P donation and organ transplantation; (2) attitude toward the manipulation of the body; (3) religious variables; and (4) sociofamily variables, especially in relation to the couple. The Guinean population emigrant to Spain has an unfriendly attitude toward organ donation. Copyright © 2017 Elsevier Inc. All rights reserved.

Identifying key demographic parameters of a small island–associated population of Indo-Pacific bottlenose dolphins (Reunion, Indian Ocean)

Science.gov (United States)

Estrade, Vanessa; Fayan, Jacques

2017-01-01

Photo-identification surveys of Indo-Pacific bottlenose dolphins were conducted from 2009 to 2014 off Reunion Island (55°E33’/21°S07’), in the Indian Ocean. Robust Design models were applied to produce the most reliable estimate of population abundance and survival rate, while accounting for temporary emigration from the survey area (west coast). The sampling scheme consisted of a five-month (June–October) sampling period in each year of the study. The overall population size at Reunion was estimated to be 72 individuals (SE = 6.17, 95%CI = 61–85), based on a random temporary emigration (γ”) of 0.096 and a proportion of 0.70 (SE = 0.03) distinct individuals. The annual survival rate was 0.93 (±0.018 SE, 95%CI = 0.886–0.958) and was constant over time and between sexes. Models considering gender groups indicated different movement patterns between males and females. Males showed null or quasi-null temporary emigration (γ” = γ’ < 0.01), while females showed a random temporary emigration (γ”) of 0.10, suggesting that a small proportion of females was outside the survey area during each primary sampling period. Sex-specific temporary migration patterns were consistent with movement and residency patterns observed in other areas. The Robust Design approach provided an appropriate sampling scheme for deriving island-associated population parameters, while allowing to restrict survey effort both spatially (i.e. west coast only) and temporally (five months per year). Although abundance and survival were stable over the six years, the small population size of fewer than 100 individuals suggested that this population is highly vulnerable. Priority should be given to reducing any potential impact of human activity on the population and its habitat. PMID:28640918

Identifying key demographic parameters of a small island-associated population of Indo-Pacific bottlenose dolphins (Reunion, Indian Ocean).

Science.gov (United States)

Dulau, Violaine; Estrade, Vanessa; Fayan, Jacques

2017-01-01

Photo-identification surveys of Indo-Pacific bottlenose dolphins were conducted from 2009 to 2014 off Reunion Island (55°E33'/21°S07'), in the Indian Ocean. Robust Design models were applied to produce the most reliable estimate of population abundance and survival rate, while accounting for temporary emigration from the survey area (west coast). The sampling scheme consisted of a five-month (June-October) sampling period in each year of the study. The overall population size at Reunion was estimated to be 72 individuals (SE = 6.17, 95%CI = 61-85), based on a random temporary emigration (γ") of 0.096 and a proportion of 0.70 (SE = 0.03) distinct individuals. The annual survival rate was 0.93 (±0.018 SE, 95%CI = 0.886-0.958) and was constant over time and between sexes. Models considering gender groups indicated different movement patterns between males and females. Males showed null or quasi-null temporary emigration (γ" = γ' < 0.01), while females showed a random temporary emigration (γ") of 0.10, suggesting that a small proportion of females was outside the survey area during each primary sampling period. Sex-specific temporary migration patterns were consistent with movement and residency patterns observed in other areas. The Robust Design approach provided an appropriate sampling scheme for deriving island-associated population parameters, while allowing to restrict survey effort both spatially (i.e. west coast only) and temporally (five months per year). Although abundance and survival were stable over the six years, the small population size of fewer than 100 individuals suggested that this population is highly vulnerable. Priority should be given to reducing any potential impact of human activity on the population and its habitat.

Identifying key demographic parameters of a small island-associated population of Indo-Pacific bottlenose dolphins (Reunion, Indian Ocean.

Directory of Open Access Journals (Sweden)

Violaine Dulau

Full Text Available Photo-identification surveys of Indo-Pacific bottlenose dolphins were conducted from 2009 to 2014 off Reunion Island (55°E33'/21°S07', in the Indian Ocean. Robust Design models were applied to produce the most reliable estimate of population abundance and survival rate, while accounting for temporary emigration from the survey area (west coast. The sampling scheme consisted of a five-month (June-October sampling period in each year of the study. The overall population size at Reunion was estimated to be 72 individuals (SE = 6.17, 95%CI = 61-85, based on a random temporary emigration (γ" of 0.096 and a proportion of 0.70 (SE = 0.03 distinct individuals. The annual survival rate was 0.93 (±0.018 SE, 95%CI = 0.886-0.958 and was constant over time and between sexes. Models considering gender groups indicated different movement patterns between males and females. Males showed null or quasi-null temporary emigration (γ" = γ' < 0.01, while females showed a random temporary emigration (γ" of 0.10, suggesting that a small proportion of females was outside the survey area during each primary sampling period. Sex-specific temporary migration patterns were consistent with movement and residency patterns observed in other areas. The Robust Design approach provided an appropriate sampling scheme for deriving island-associated population parameters, while allowing to restrict survey effort both spatially (i.e. west coast only and temporally (five months per year. Although abundance and survival were stable over the six years, the small population size of fewer than 100 individuals suggested that this population is highly vulnerable. Priority should be given to reducing any potential impact of human activity on the population and its habitat.

Los países del este nuevo foco de emigración de la Europa actual. Su incidencia en España

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M.ª Pilar González Yanci

2017-11-01

Full Text Available Eastern European countries once again a source of emigration in Europe today. Its affect on Spain. In the complex framework of European migration, both Eastern European countries and Spain play an important role. With great analogies in the past, transformations occurred at the end of the 1980s which have led Eastern European countries to be one of the main sources of emigrants in Europe. Spain is now on the receiving end. The relationship between the two is established in this context, with Spain today being one of the destinations of Eastern European emigrants, who are in an intermediate position within the array of peoples emigrating to the country - from highly-qualified first-world professionals holding important jobs and belonging to the highest socio-economic class to unskilled or under-skilled third world emigrants living at the lower end of the socio-economic scale and often marginalized.

Achieving high mobility ZnO : Al at very high growth rates by dc filtered cathodic arc deposition

International Nuclear Information System (INIS)

Mendelsberg, R J; Lim, S H N; Wallig, J; Anders, A; Zhu, Y K; Milliron, D J

2011-01-01

Achieving a high growth rate is paramount for making large-area transparent conducting oxide coatings at a low cost. Unfortunately, the quality of thin films grown by most techniques degrades as the growth rate increases. Filtered dc cathodic arc is a lesser known technique which produces a stream of highly ionized plasma, in stark contrast to the neutral atoms produced by standard sputter sources. Ions bring a large amount of potential energy to the growing surface which is in the form of heat, not momentum. By minimizing the distance from cathode to substrate, the high ion flux gives a very high effective growth temperature near the film surface without causing damage from bombardment. The high surface temperature is a direct consequence of the high growth rate and allows for high-quality crystal growth. Using this technique, 500-1300 nm thick and highly transparent ZnO : Al films were grown on glass at rates exceeding 250 nm min -1 while maintaining resistivity below 5 x 10 -4 Ω cm with electron mobility as high as 60 cm 2 V -1 s -1 . (fast track communication)

High dose rate endobronchial brachytherapy - treatment technique

International Nuclear Information System (INIS)

Carvalho, Heloisa de Andrade; Aisen, Salim; Haddad, Cecilia Maria Kalil; Nadalin, Wladimir; Pedreira Junior, Wilson Leite; Chavantes, Maria Cristina

1998-01-01

High dose rate endobronchial brachytherapy is efficient in symptom relief due to obstructive endobronchial malignancies. However, it's role in survival improvement for patients with lung cancer is not yet established. The use of this treatment in increasing, specially in the developing countries. The purpose of this paper is to present the treatment technique used in the Radiotherapy Department of the Hospital da Clinicas, University of Sao Paulo, based on an experience of 60 cases treated with 180 procedures. Some practical suggestions and rules adopted in the Department are described. The severe complications rate is 6.7%, demonstrating an adequate patient selection associated with the technique utilized. (author)

Diaspora diplomacy – about a new dimension of diplomacy, the example of a New Emigration non-governmental organisation

Directory of Open Access Journals (Sweden)

Martyna Tomiczek

2011-12-01

Full Text Available In recent years, the migration movement, which tends to be oriented towards Great Britain, reached its climax at the moment when Poland became a fully-fledged member of the European Union. Years following Poland’s accession have witnessed an enormous outbreak of Polish exodus – leaving their own country they were trying to find a new place abroad. Among the plurality of motives, we could point to such as: hope for a better life and improving personal material situation, a more interesting life in a multinational society and becoming a “world man”, necessity and curiosity. Results were also much more complicated than anyone could ever imagine. The causes and effects of the Polish exodus constituted an inescapable subject of analysis and research. The Polish migration movement can be considered in many aspects. This unique phenomenon has its economic, political, social and psychosocial dimensions – each of them is worth profound analysis. Within each of the previously mentioned dimensions a researcher would find singularly important and specific phenomena regarding the migration movement – phenomena which are at the very core of the lives of migrants’ succeeding generations. Undoubtedly, one of the dimensions of the New Polish Emigration analysis could be referred to public diplomacy strategy. This thesis will be the main framework of this paper

Inverse methods for the mechanical characterization of materials at high strain rates

Directory of Open Access Journals (Sweden)

Casas-Rodriguez J.P.

2012-08-01

Full Text Available Mechanical material characterization represents a research challenge. Furthermore, special attention is directed to material characterization at high strain rates as the mechanical properties of some materials are influenced by the rate of loading. Diverse experimental techniques at high strain rates are available, such as the drop-test, the Taylor impact test or the Split Hopkinson pressure bar among others. However, the determination of the material parameters associated to a given mathematical constitutive model from the experimental data is a complex and indirect problem. This paper presents a material characterization methodology to determine the material parameters of a given material constitutive model from a given high strain rate experiment. The characterization methodology is based on an inverse technique in which an inverse problem is formulated and solved as an optimization procedure. The input of the optimization procedure is the characteristic signal from the high strain rate experiment. The output of the procedure is the optimum set of material parameters determined by fitting a numerical simulation to the high strain rate experimental signal.

Dynamic tensile fracture of mortar at ultra-high strain-rates

International Nuclear Information System (INIS)

Erzar, B.; Buzaud, E.; Chanal, P.-Y.

2013-01-01

During the lifetime of a structure, concrete and mortar may be exposed to highly dynamic loadings, such as impact or explosion. The dynamic fracture at high loading rates needs to be well understood to allow an accurate modeling of this kind of event. In this work, a pulsed-power generator has been employed to conduct spalling tests on mortar samples at strain-rates ranging from 2 × 10 4 to 4 × 10 4  s −1 . The ramp loading allowed identifying the strain-rate anytime during the test. A power law has been proposed to fit properly the rate-sensitivity of tensile strength of this cementitious material over a wide range of strain-rate. Moreover, a specimen has been recovered damaged but unbroken. Micro-computed tomography has been employed to study the characteristics of the damage pattern provoked by the dynamic tensile loading

Incorporating movement patterns to improve survival estimates for juvenile bull trout

Science.gov (United States)

Bowerman, Tracy; Budy, Phaedra

2012-01-01

Populations of many fish species are sensitive to changes in vital rates during early life stages, but our understanding of the factors affecting growth, survival, and movement patterns is often extremely limited for juvenile fish. These critical information gaps are particularly evident for bull trout Salvelinus confluentus, a threatened Pacific Northwest char. We combined several active and passive mark–recapture and resight techniques to assess migration rates and estimate survival for juvenile bull trout (70–170 mm total length). We evaluated the relative performance of multiple survival estimation techniques by comparing results from a common Cormack–Jolly–Seber (CJS) model, the less widely used Barker model, and a simple return rate (an index of survival). Juvenile bull trout of all sizes emigrated from their natal habitat throughout the year, and thereafter migrated up to 50 km downstream. With the CJS model, high emigration rates led to an extreme underestimate of apparent survival, a combined estimate of site fidelity and survival. In contrast, the Barker model, which allows survival and emigration to be modeled as separate parameters, produced estimates of survival that were much less biased than the return rate. Estimates of age-class-specific annual survival from the Barker model based on all available data were 0.218±0.028 (estimate±SE) for age-1 bull trout and 0.231±0.065 for age-2 bull trout. This research demonstrates the importance of incorporating movement patterns into survival analyses, and we provide one of the first field-based estimates of juvenile bull trout annual survival in relatively pristine rearing conditions. These estimates can provide a baseline for comparison with future studies in more impacted systems and will help managers develop reliable stage-structured population models to evaluate future recovery strategies.

Endorectal high dose rate brachytherapy quality assurance

International Nuclear Information System (INIS)

Devic, S.; Vuong, T.; Evans, M.; Podgorsak, E.

2008-01-01

We describe our quality assurance method for preoperative high dose rate (HDR) brachytherapy of endorectal tumours. Reproduction of the treatment planning dose distribution on a daily basis is crucial for treatment success. Due to the cylindrical symmetry, two types of adjustments are necessary: applicator rotation and dose distribution shift along the applicator axis. (author)

Miniaturized Stretchable and High-Rate Linear Supercapacitors.

Science.gov (United States)

Zhu, Wenjun; Zhang, Yang; Zhou, Xiaoshuang; Xu, Jiang; Liu, Zunfeng; Yuan, Ningyi; Ding, Jianning

2017-12-01

Linear stretchable supercapacitors have attracted much attention because they are well suited to applications in the rapidly expanding field of wearable electronics. However, poor conductivity of the electrode material, which limits the transfer of electrons in the axial direction of the linear supercapacitors, leads to a serious loss of capacity at high rates. To solve this problem, we use gold nanoparticles to decorate aligned multiwall carbon nanotube to fabricate stretchable linear electrodes. Furthermore, we have developed fine stretchable linear supercapacitors, which exhibited an extremely high elasticity up to 400% strain with a high capacitance of about 8.7 F g -1 at the discharge current of 1 A g -1 .

High-Strain Rate Failure Modeling Incorporating Shear Banding and Fracture

Science.gov (United States)

2017-11-22

High Strain Rate Failure Modeling Incorporating Shear Banding and Fracture The views, opinions and/or findings contained in this report are those of...SECURITY CLASSIFICATION OF: 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 13. SUPPLEMENTARY NOTES 12. DISTRIBUTION AVAILIBILITY STATEMENT 6. AUTHORS...Report as of 05-Dec-2017 Agreement Number: W911NF-13-1-0238 Organization: Columbia University Title: High Strain Rate Failure Modeling Incorporating

Dispersal and survival rates of adult and juvenile Red-tailed tropicbirds (Phaethon rubricauda exposed to potential contaminants

Directory of Open Access Journals (Sweden)

Schreiber, E. A.

2004-06-01

Full Text Available Annual survival and dispersal rates of adult and juvenile red-tailed tropicbirds were examined in connection with exposure to heavy metals. From 1990-2000 the incineration of a U.S. stockpile of chemical weapons stored at Johnston Atoll exposed nesting tropicbirds to increased levels of human disturbance, smoke stack emissions and potential leaks. Using a multi-state mark-recapture modeling approach, birds nesting in this site (downwind of the plant were compared to those nesting in a reference site (upwind of the plant with less human disturbance, no exposure to smoke stack emissions or other potential incineration emissions. We did not find any difference in survival of adults or juveniles when comparing the two sites. Adult breeding dispersal rates did not differ between the sites but we did find differences in the age-specific natal dispersal rates. Birds fledged from downwind areas were less likely to return to their natal area to nest and more likely to immigrate to the upwind area than vice-versa. This asymmetry in emigration rates is believed to be due to differing vegetation densities and has implications for vegetation management in relation to tropicbird nest success and population size.

High freight rates hinder oil markets' return to equilibrium

International Nuclear Information System (INIS)

Anon

2005-01-01

Hurricane damage to refineries in the US has created shortages of refined products there, boosting imports and sending freight rates across the Atlantic to record levels. The situation was made worse for a time by a strike at France's main oil terminals in the Mediterranean, which prevented some oil tankers from being rapidly redeployed to routes across the Atlantic. Worldscale (WS) rates for routes from the UK and Europe to the US Atlantic and Gulf Coasts rose well above WS500 for clean tonnage during October. High rates were nevertheless not simply confined to product tankers crossing the Atlantic. Rates for crude tankers to the US have also risen, and tightness has begun to appear in some other markets as well. The net result has been to slow down the movement of oil from regions of surplus to those of scarcity, depressing prices in the former and keeping them at high levels in the latter. Atlantic tanker markets look like remaining tight for the rest of the year and perhaps beyond. (author)

Brittle materials at high-loading rates: an open area of research

Science.gov (United States)

Forquin, Pascal

2017-01-01

Brittle materials are extensively used in many civil and military applications involving high-strain-rate loadings such as: blasting or percussive drilling of rocks, ballistic impact against ceramic armour or transparent windshields, plastic explosives used to damage or destroy concrete structures, soft or hard impacts against concrete structures and so on. With all of these applications, brittle materials are subjected to intense loadings characterized by medium to extremely high strain rates (few tens to several tens of thousands per second) leading to extreme and/or specific damage modes such as multiple fragmentation, dynamic cracking, pore collapse, shearing, mode II fracturing and/or microplasticity mechanisms in the material. Additionally, brittle materials exhibit complex features such as a strong strain-rate sensitivity and confining pressure sensitivity that justify expending greater research efforts to understand these complex features. Currently, the most popular dynamic testing techniques used for this are based on the use of split Hopkinson pressure bar methodologies and/or plate-impact testing methods. However, these methods do have some critical limitations and drawbacks when used to investigate the behaviour of brittle materials at high loading rates. The present theme issue of Philosophical Transactions A provides an overview of the latest experimental methods and numerical tools that are currently being developed to investigate the behaviour of brittle materials at high loading rates. This article is part of the themed issue 'Experimental testing and modelling of brittle materials at high strain rates'.

Flashing motor at high transition rate

International Nuclear Information System (INIS)

Ai Baoquan; Wang Liqiu; Liu Lianggang

2007-01-01

The movement of a Brownian particle in a fluctuating two-state periodic potential is investigated. At high transition rate, we use a perturbation method to obtain the analytical solution of the model. It is found that the net current is a peaked function of thermal noise, barrier height and the fluctuation ratio between the two states. The thermal noise may facilitate the directed motion at a finite intensity. The asymmetry parameter of the potential is sensitive to the direction of the net current

Mechanical characterization of rocks at high strain rate

Directory of Open Access Journals (Sweden)

Konstantinov A.

2012-08-01

Full Text Available The paper presents the dynamic characterization in tension and compression of three rocks, Carrara marble, Onsernone gneiss and Peccia Marble, at high strain-rates. Two versions of a Split Hopkinson Bar have been used. The version for direct tension tests is installed at the DynaMat Laboratory of the University of Applied Sciences of Southern Switzerland, while the traditional version in compression is installed at the Laboratory of Dynamic Investigation of Materials of Lobachevsky State University. Results of the tests show a significantly strain-rate sensitive behaviour, exhibiting dynamic strength increasing with strain-rate. The experimental research has been developed in the frame of the Swiss-Russian Joint Research Program.

Evidence that a Highway Reduces Apparent Survival Rates of Squirrel Gliders

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Sarah C. McCall

2010-09-01

Full Text Available Roads and traffic are prominent components of most landscapes throughout the world, and their negative effects on the natural environment can extend for hundreds or thousands of meters beyond the road. These effects include mortality of wildlife due to collisions with vehicles, pollution of soil and air, modification of wildlife behavior in response to noise, creation of barriers to wildlife movement, and establishment of dispersal conduits for some plant and animal species. In southeast Australia, much of the remaining habitat for the squirrel glider, Petaurus norfolcensis, is located in narrow strips of Eucalyptus woodland that is adjacent to roads and streams, as well as in small patches of woodland vegetation that is farther from roads. We evaluated the effect of traffic volume on squirrel gliders by estimating apparent annual survival rates of adults along the Hume Freeway and nearby low-traffic-volume roads. We surveyed populations of squirrel gliders by trapping them over 2.5 years, and combined these data with prior information on apparent survival rates in populations located away from freeways to model the ratio of apparent annual survival rates in both site types. The apparent annual survival rate of adult squirrel gliders living along the Hume Freeway was estimated to be approximately 60% lower than for squirrel gliders living near local roads. The cause of the reduced apparent survival rate may be due to higher rates of mortality and/or higher emigration rates adjacent to the Hume Freeway compared with populations near smaller country roads. Management options for population persistence will be influenced by which of these factors is the primary cause of a reduced apparent survival rate.

High rate loading tests and impact tests of concrete and reinforcement

International Nuclear Information System (INIS)

Takeda, J.I.; Tachikawa, H.; Fujimoto, K.

1982-01-01

The responses of reinforced concrete structural members and structures subjected to impact or impulsive loadings are affected by the behavior of constituent concrete and reinforcement which are the synthesis of the rate effects and the contribution of propagating stress waves of them. The rate effects and the contribution of stress waves do not have the same tendency in the variation of magnitude of them with speed of impact or impulsive loadings. Therefore the rate effects, mentioned above, should be obtained by the tests minimized the effect of stress waves (high rate loading test). This paper deals with the testing techniques with high rate loadings and impact, and also reports the main results of these tests. (orig.) [de

High Strain Rate Tensile Testing of Silver Nanowires: Rate-Dependent Brittle-to-Ductile Transition.

Science.gov (United States)

Ramachandramoorthy, Rajaprakash; Gao, Wei; Bernal, Rodrigo; Espinosa, Horacio

2016-01-13

The characterization of nanomaterials under high strain rates is critical to understand their suitability for dynamic applications such as nanoresonators and nanoswitches. It is also of great theoretical importance to explore nanomechanics with dynamic and rate effects. Here, we report in situ scanning electron microscope (SEM) tensile testing of bicrystalline silver nanowires at strain rates up to 2/s, which is 2 orders of magnitude higher than previously reported in the literature. The experiments are enabled by a microelectromechanical system (MEMS) with fast response time. It was identified that the nanowire plastic deformation has a small activation volume (ductile failure mode transition was observed at a threshold strain rate of 0.2/s. Transmission electron microscopy (TEM) revealed that along the nanowire, dislocation density and spatial distribution of plastic regions increase with increasing strain rate. Furthermore, molecular dynamic (MD) simulations show that deformation mechanisms such as grain boundary migration and dislocation interactions are responsible for such ductility. Finally, the MD and experimental results were interpreted using dislocation nucleation theory. The predicted yield stress values are in agreement with the experimental results for strain rates above 0.2/s when ductility is pronounced. At low strain rates, random imperfections on the nanowire surface trigger localized plasticity, leading to a brittle-like failure.

Activated carbon derived from melaleuca barks for outstanding high-rate supercapacitors

Science.gov (United States)

Luo, Qiu-Ping; Huang, Liang; Gao, Xiang; Cheng, Yongliang; Yao, Bin; Hu, Zhimi; Wan, Jun; Xiao, Xu; Zhou, Jun

2015-07-01

Activated carbon (AC) was prepared via carbonizing melaleuca bark in an argon atmosphere at 600 °C followed with KOH activation for high-rate supercapacitors. This AC electrode has a high capacitance of 233 F g-1 at a scan rate of 2 mV s-1 and an excellent rate capability of ˜80% when increasing the sweep rate from 2 to 500 mV s-1. The symmetric supercapacitor assembled by the above electrode can deliver a high energy density of 4.2 Wh kg-1 with a power density of 1500 W kg-1 when operated in the voltage range of 0-1 V in 1 M H2SO4 aqueous electrolyte while maintaining great cycling stability (less than 5% capacitance loss after 10 000 cycles at sweep rate of 100 mV s-1). All the outstanding electrochemical performances make this AC electrode a promising candidate for potential energy storage application.

High repetition rate intense ion beam source

International Nuclear Information System (INIS)

Hammer, D.A.; Glidden, S.C.; Noonan, B.

1992-01-01

This final report describes a ≤ 150kV, 40kA, 100ns high repetition rate pulsed power system and intense ion beam source which is now in operation at Cornell University. Operation of the Magnetically-controlled Anode Plasma (MAP) ion diode at > 100Hz (burst mode for up to 10 pulse bursts) provides an initial look at repetition rate limitations of both the ion diode and beam diagnostics. The pulsed power systems are capable of ≥ 1kHz operation (up to 10 pulse bursts), but ion diode operation was limited to ∼100Hz because of diagnostic limitations. By varying MAP diode operating parameters, ion beams can be extracted at a few 10s of keV or at up to 150keV, the corresponding accelerating gap impedance ranging from about 1Ω to about 10Ω. The ability to make hundreds of test pulses per day at an average repetition rate of about 2 pulses per minute permits statistical analysis of diode operation as a function of various parameters. Most diode components have now survived more than 10 4 pulses, and the design and construction of the various pulsed power components of the MAP diode which have enabled us to reach this point are discussed. A high speed data acquisition system and companion analysis software capable of acquiring pulse data at 1ms intervals (in bursts of up to 10 pulses) and processing it in ≤ min is described

U.S. High School Graduation Rates: Patterns and Explanations

OpenAIRE

Richard J. Murnane

2013-01-01

I survey the evidence on patterns in U.S. high school graduation rates over the period 1970–2010 and report the results of new research conducted to fill in holes in the evidence. I begin by pointing out the strengths and limitations of existing data sources. I then describe six striking patterns in graduation rates. They include stagnation over the last three decades of the twentieth century, significant race-, income-, and gender-based gaps, and significant increases in graduation rates o...

Predicting High Frequency Exchange Rates using Machine Learning

OpenAIRE

Palikuca, Aleksandar; Seidl,, Timo

2016-01-01

This thesis applies a committee of Artificial Neural Networks and Support Vector Machines on high-dimensional, high-frequency EUR/USD exchange rate data in an effort to predict directional market movements on up to a 60 second prediction horizon. The study shows that combining multiple classifiers into a committee produces improved precision relative to the best individual committee members and outperforms previously reported results. A trading simulation implementing the committee classifier...

A copper bromide vapour laser with a high pulse repetition rate

International Nuclear Information System (INIS)

Shiyanov, D V; Evtushenko, Gennadii S; Sukhanov, V B; Fedorov, V F

2002-01-01

The results of an experimental study of a copper bromide vapour laser with a discharge-channel diameter above 2.5 cm and a high pump-pulse repetition rate are presented. A TGU1-1000/25 high-power tacitron used as a switch made it possible to obtain for the first time a fairly high output radiation power for pump-pulse repetition rates exceeding 200 kHz. At a maximum pump-pulse repetition rate of 250 kHz achieved in a laser tube 2.6 cm in diameter and 76 cm long, the output power was 1.5 W. The output powers of 3 and 10.5 W were reached for pump-pulse repetition rates of 200 and 100 kHz, respectively. These characteristics were obtained without circulating a buffer gas and (or) low-concentration active impurities through the active volume. (active media. lasers)

Split-Hopkinson Pressure Bar: an experimental technique for high strain rate tests

International Nuclear Information System (INIS)

Sharma, S.; Chavan, V.M.; Agrawal, R.G.; Patel, R.J.; Kapoor, R.; Chakravartty, J.K.

2011-06-01

Mechanical properties of materials are, in general, strain rate dependent, i.e. they respond differently at quasi-static and higher strain rate condition. The Split-Hopkinson Pressure Bar (SHPB), also referred to as Kolsky bar is a commonly used setup for high strain rate testing. SHPB is suitable for high strain rate test in strain rate range of 10 2 to 10 4 s -1 . These high strain rate data are required for safety and structural integrity assessment of structures subjected to dynamic loading. As high strain rate data are not easily available in open literature need was felt for setting up such high strain rate testing machine. SHPB at BARC was designed and set-up inhouse jointly by Refuelling Technology Division and Mechanical Metallurgy Division, at Hall no. 3, BARC. A number of conceptual designs for SHPB were thought of and the optimized design was worked out. The challenges of precision tolerance, straightness in bars and design and proper functioning of pneumatic gun were met. This setup has been used extensively to study the high strain rate material behavior. This report introduces the SHPB in general and the setup at BARC in particular. The history of development of SHPB, the basic formulations of one dimensional wave propagation, the relations between the wave velocity, particle velocity and elastic strain in a one dimensional bar, and the equations used to obtain the final stress vs. strain curves are described. The calibration of the present setup, the pre-test calculations and the posttest analysis of data are described. Finally some of the experimental results on different materials such as Cu, SS305, SA516 and Zr, at room temperature and elevated temperatures are presented. (author)

Precise muon drift tube detectors for high background rate conditions

Energy Technology Data Exchange (ETDEWEB)

Engl, Albert

2011-08-04

The muon spectrometer of the ATLAS-experiment at the Large Hadron Collider consists of drift tube chambers, which provide the precise measurement of trajectories of traversing muons. In order to determine the momentum of the muons with high precision, the measurement of the position of the muon in a single tube has to be more accurate than {sigma}{<=}100 {mu}m. The large cross section of proton-proton-collisions and the high luminosity of the accelerator cause relevant background of neutrons and {gamma}s in the muon spectrometer. During the next decade a luminosity upgrade to 5.10{sup 34} cm{sup -2}s{sup -1} is planned, which will increase the background counting rates considerably. In this context this work deals with the further development of the existing drift chamber technology to provide the required accuracy of the position measurement under high background conditions. Two approaches of improving the drift tube chambers are described: - In regions of moderate background rates a faster and more linear drift gas can provide precise position measurement without changing the existing hardware. - At very high background rates drift tube chambers consisting of tubes with a diameter of 15 mm are a valuable candidate to substitute the CSC muon chambers. The single tube resolution of the gas mixture Ar:CO{sub 2}:N{sub 2} in the ratio of 96:3:1 Vol %, which is more linear and faster as the currently used drift gas Ar:CO{sub 2} in the ratio of 97:3 Vol %, was determined at the Cosmic Ray Measurement Facility at Garching and at high {gamma}-background counting rates at the Gamma Irradiation Facility at CERN. The alternative gas mixture shows similar resolution without background. At high background counting rates it shows better resolution as the standard gas. To analyse the data the various parts of the setup have to be aligned precisely to each other. The change to an alternative gas mixture allows the use of the existing hardware. The second approach are drift tubes

Decay rate of the false vacuum at high temperatures

International Nuclear Information System (INIS)

Eboli, O.J.P.; Marques, G.C.

1986-01-01

We investigate, within the semiclassical approach, the high temperature behaviour of the decay rate (Γ) of the metastable vacuum in Field Theory. We exhibit some exactly soluble (1+1) and (3+1) dimensional examples and develop a formal expression for γ in the high temperature limit. (Author) [pt

Study of magnetorheological fluids at high shear rates

Energy Technology Data Exchange (ETDEWEB)

Wang, Xiaojie; Gordaninejad, Faramarz [University of Nevada, Department of Mechanical Engineering, Reno, NV (United States)

2006-08-15

The tunable rheological properties of magnetorheological (MR) materials at high shear rates are studied using a piston-driven flow-mode-type rheometer. The proposed method provides measurement of the apparent viscosity and yield stress of MR fluids for a shear rate range of 50 to 40,000 s{sup -1}. The rheological properties of a commercial MR fluid, as well as a newly developed MR polymeric gel, and a ferrofluid-based MR fluid are investigated. The results for apparent viscosity and dynamic and static shear stresses under different applied magnetic fields are reported. (orig.)

On high interest rates in Brazil

Directory of Open Access Journals (Sweden)

Francisco Lafaiete Lopes

2014-03-01

Full Text Available This article examines the question of why interest rates are so high in Brazil as compared to the international average. It looks at theoretical arguments based on excessive government deficits, structural lack of private savings, inflation bias, excessive investment demand and fear of floating. An informal look at the evidence does not strongly corroborate any of these arguments. Hence a wise central bank should consider "testing" the market to make sure it is not dealing with an extreme equilibrium configuration or a long standing disequilibrium.

Shifting tides in the emigration patterns of Canadian physicians to the United States: a cross-sectional secondary data analysis.

Science.gov (United States)

Freeman, Thomas R; Petterson, Stephen; Finnegan, Sean; Bazemore, Andrew

2016-12-01

The relative ease of movement of physicians across the Canada/US border has led to what is sometimes referred to as a 'brain drain' and previous analysis estimated that the equivalent of two graduating classes from Canadian medical schools were leaving to practice in the US each year. Both countries fill gaps in physician supply with international medical graduates (IMGs) so the movement of Canadian trained physicians to the US has international ramifications. Medical school enrolments have been increased on both sides of the border, yet there continues to be concerns about adequacy of physician human resources. This analysis was undertaken to re-examine the issue of Canadian physician migration to the US. We conducted a cross-sectional analysis of the 2015 American Medical Association (AMA) Masterfile to identify and locate any graduates of Canadian schools of medicine (CMGs) working in the United States in direct patient care. We reviewed annual reports of the Canadian Resident Matching Service (CaRMS); the Canadian Post-MD Education Registry (CAPER); and the Canadian Collaborative Centre for Physician Resources (C3PR). Beginning in the early 1990s the number of CMGs locating in the U.S. reached an all-time high and then abruptly dropped off in 1995. CMGs are going to the US for post-graduate training in smaller numbers and, are less likely to remain than at any time since the 1970's. This four decade retrospective found considerable variation in the migration pattern of CMGs to the US. CMGs' decision to emigrate to the U.S. may be influenced by both 'push' and 'pull' factors. The relative strength of these factors changed and by 2004, more CMGs were returning from abroad than were leaving and the current outflow is negligible. This study supports the need for medical human resource planning to assume a long-term view taking into account national and international trends to avoid the rapid changes that were observed. These results are of importance to medical

High repetition rate burst-mode spark gap

International Nuclear Information System (INIS)

Faltens, A.; Reginato, L.; Hester, R.; Chesterman, A.; Cook, E.; Yokota, T.; Dexter, W.

1978-01-01

Results are presented on the design and testing of a pressurized gas blown spark gap switch capable of high repetition rates in a burst mode of operation. The switch parameters which have been achieved are as follows: 220-kV, 42-kA, a five pulse burst at 1-kHz, 12-ns risetime, 2-ns jitter at a pulse width of 50-ns

Brittle materials at high-loading rates: an open area of research

Science.gov (United States)

2017-01-01

Brittle materials are extensively used in many civil and military applications involving high-strain-rate loadings such as: blasting or percussive drilling of rocks, ballistic impact against ceramic armour or transparent windshields, plastic explosives used to damage or destroy concrete structures, soft or hard impacts against concrete structures and so on. With all of these applications, brittle materials are subjected to intense loadings characterized by medium to extremely high strain rates (few tens to several tens of thousands per second) leading to extreme and/or specific damage modes such as multiple fragmentation, dynamic cracking, pore collapse, shearing, mode II fracturing and/or microplasticity mechanisms in the material. Additionally, brittle materials exhibit complex features such as a strong strain-rate sensitivity and confining pressure sensitivity that justify expending greater research efforts to understand these complex features. Currently, the most popular dynamic testing techniques used for this are based on the use of split Hopkinson pressure bar methodologies and/or plate-impact testing methods. However, these methods do have some critical limitations and drawbacks when used to investigate the behaviour of brittle materials at high loading rates. The present theme issue of Philosophical Transactions A provides an overview of the latest experimental methods and numerical tools that are currently being developed to investigate the behaviour of brittle materials at high loading rates. This article is part of the themed issue ‘Experimental testing and modelling of brittle materials at high strain rates’. PMID:27956517

High frame rate retrospectively triggered Cine MRI for assessment of murine diastolic function.

Science.gov (United States)

Coolen, Bram F; Abdurrachim, Desiree; Motaal, Abdallah G; Nicolay, Klaas; Prompers, Jeanine J; Strijkers, Gustav J

2013-03-01

To assess left ventricular (LV) diastolic function in mice with Cine MRI, a high frame rate (>60 frames per cardiac cycle) is required. For conventional electrocardiography-triggered Cine MRI, the frame rate is inversely proportional to the pulse repetition time (TR). However, TR cannot be lowered at will to increase the frame rate because of gradient hardware, spatial resolution, and signal-to-noise limitations. To overcome these limitations associated with electrocardiography-triggered Cine MRI, in this paper, we introduce a retrospectively triggered Cine MRI protocol capable of producing high-resolution high frame rate Cine MRI of the mouse heart for addressing left ventricular diastolic function. Simulations were performed to investigate the influence of MRI sequence parameters and the k-space filling trajectory in relation to the desired number of frames per cardiac cycle. An optimized protocol was applied in vivo and compared with electrocardiography-triggered Cine for which a high-frame rate could only be achieved by several interleaved acquisitions. Retrospective high frame rate Cine MRI proved superior to the interleaved electrocardiography-triggered protocols. High spatial-resolution Cine movies with frames rates up to 80 frames per cardiac cycle were obtained in 25 min. Analysis of left ventricular filling rate curves allowed accurate determination of early and late filling rates and revealed subtle impairments in left ventricular diastolic function of diabetic mice in comparison with nondiabetic mice. Copyright © 2012 Wiley Periodicals, Inc.

A new high rate positron lifetime measurement system

International Nuclear Information System (INIS)

Bedwell, M.O.; Paulus, T.J.

1979-01-01

Positron lifetime measuring system, a technique to perform non-destructive studies on the internal structure of materials, has many components common to those used for nuclear time spectroscopy systems. In each case, a timing coincidence curve is measured for the energy range of interest, and this is accomplished in a typical timing coincidence system. The paper first describes the conventional timing coincidence system, then a new fast timing system is introduced. Comparing to the conventional fast/slow timing system, the fast timing technique offers reduced complexity, lower system cost, and improved high data rate capability. Experimental results show that the FWHM timing resolution ranges from 190 ps for a 1.1 : 1 dynamic range to 337 ps for a 100 : 1 dynamic range of signals with 60 Co. As for the timing resolution as a function of energy, the FWHM resolution for each channel ranges from 124 ps at 1 MeV to 400 ps at 100 keV. Since the excellent timing performance is maintained even at very high input rate, the experimenters can use much more active sources to increase the true coincidence rate and reduce data accumulation time. This method has the added advantage of minimizing long term drift effects since the experiments can be conducted in less time. (Wakatsuki, Y.)

Twinning in copper deformed at high strain rates

Indian Academy of Sciences (India)

Abstract. Copper samples having varying microstructures were deformed at high strain rates using a split-. Hopkinson pressure bar. Transmission electron microscopy results show deformation twins present in samples that were both annealed and strained, whereas samples that were annealed and left unstrained, as well ...

Digital approach to high rate gamma-ray spectrometry

Energy Technology Data Exchange (ETDEWEB)

Korolczuk, Stefan; Mianowski, Slawomir; Rzadkiewicz, Jacek; Sibczynski, Pawel; Swiderski, Lukasz; Szewinski, Jaroslaw; Zychor, Izabella [Narodowe Centrum Badan Jadrowych (NCBJ), 05-400 Otwock, (Poland)

2015-07-01

Basic concepts and preliminary results of creating high rate digital spectrometry system using efficient ADCs and latest FPGA are presented as well as a comparison with commercially available devices. The possibility to use such systems, coupled to scintillators, in plasma experiments is discussed. (authors)

Pedalling rate affects endurance performance during high-intensity cycling

DEFF Research Database (Denmark)

Nielsen, Jens Steen; Hansen, Ernst Albin; Sjøgaard, Gisela

2004-01-01

The purpose of this study into high-intensity cycling was to: (1) test the hypothesis that endurance time is longest at a freely chosen pedalling rate (FCPR), compared to pedalling rates 25% lower (FCPR-25) and higher (FCPR+25) than FCPR, and (2) investigate how physiological variables......, and endurance time at W90 with FCPR-25, FCPR, and FCPR+25. Power reserve was calculated as the difference between applied power output at a given pedalling rate and peak crank power at this same pedalling rate. W90 was 325 (47) W. FCPR at W90 was 78 (11) rpm, resulting in FCPR-25 being 59 (8) rpm and FCPR+25...... time was negatively related to VO(2max), W90 and % MHC I, while positively related to power reserve. In conclusion, at group level, endurance time was longer at FCPR and at a pedalling rate 25% lower compared to a pedalling rate 25% higher than FCPR. Further, inter-individual physiological variables...

Terorizam i jugoslovenska politička emigracija

Directory of Open Access Journals (Sweden)

Srđan Cvetković

2014-08-01

Full Text Available The work analyzes forms of terrorist activities of political émigrés against the communist régime in Yugoslavia that culminated from the second half of the sixties until the beginning of the eighties of the last century. Also, it gives an overview how the State reacted to challenges posed by terrorists’ through the process of neutralization of the extreme emigrants. According to the analysis executions of the emigrants reached peaks during the 1960s, then in the 1970s and between 1983–84. Intensity of the terrorist activities and the State’s radical answer to it was noticeably high during the 1970s or during the global expansion of the terrorist activities. It is indicative that serial killings of political emigrants in the USA began after 1977 following the high jacking of the plane in the USA and the arrest of the members of the SOPO terrorist organisation. Besides the terrorists many prominent political figures, journalists and media moguls, anticommunist intellectuals mostly from Germany were targeted. In an attempt to stop organised propaganda activities aimed at economic emigrant the State applied methods for neutralisation of political emigrants, threats and preventative measures against the terrorists which reached its peak at the end of the 1960s.

Transperineal high-dose-rate interstitial radiation therapy in the management of gynecologic malignancies

Energy Technology Data Exchange (ETDEWEB)

Itami, Jun; Hara, Ryuseke; Kozuka, Takuyou; Yamashita, Hideomi; Nakajima, Kaori; Shibata, Kouji; Abe, Yoshihisa; Fuse, Masashi; Ito, Masashi [International Medical Center of Japan, Tokyo (Japan). Dept. of Radiation Therapy and Oncology

2003-11-01

Background: High-dose-rate interstitial radiation therapy is a newly introduced modality, and its role in the management of gynecologic malignancies remains to be studied. Clinical experience in high-dose-rate interstitial radiation therapy was retrospectively investigated. Patients and Methods: Eight patients with primary and nine with recurrent gynecologic malignancies underwent high-dose-rate interstitial radiation therapy with/without external-beam irradiation. Fractional dose of the high-dose-rate interstitial radiation therapy ranged between 4 and 6 Gy with total doses of 15-54 Gy. Interstitial irradiation was performed twice daily with an interval of > 6 h. Results: 2-year local control rate was 75% for primary treatment and 47% for treatment of recurrence (p = 0.46). Maximum tumor size had a statistically significant impact on local control (p < 0.002). Grade 2 and 4 late complications were seen in five patients, and the incidence was significantly higher in patients with a larger volume enclosed by the prescribed fractional dose of high-dose-rate interstitial radiation therapy. The incidence of grade 2 and 4 complications at 18 months was 78% and 0% with a volume > 100 cm{sup 3} and {<=} 100 cm{sup 3}, respectively (p < 0.04). Conclusion: Although high-dose-rate interstitial radiation therapy is a promising modality, it must be applied cautiously to patients with bulky tumors because of the high incidence of serious complications. (orig.)

High-rate synthesis of microcrystalline silicon films using high-density SiH4/H2 microwave plasma

International Nuclear Information System (INIS)

Jia, Haijun; Saha, Jhantu K.; Ohse, Naoyuki; Shirai, Hajime

2007-01-01

A high electron density (> 10 11 cm -3 ) and low electron temperature (1-2 eV) plasma is produced by using a microwave plasma source utilizing a spoke antenna, and is applied for the high-rate synthesis of high quality microcrystalline silicon (μc-Si) films. A very fast deposition rate of ∼ 65 A/s is achieved at a substrate temperature of 150 deg. C with a high Raman crystallinity and a low defect density of (1-2) x 10 16 cm -3 . Optical emission spectroscopy measurements reveal that emission intensity of SiH and intensity ratio of H α /SiH are good monitors for film deposition rate and film crystallinity, respectively. A high flux of film deposition precursor and atomic hydrogen under a moderate substrate temperature condition is effective for the fast deposition of highly crystallized μc-Si films without creating additional defects as well as for the improvement of film homogeneity

03 Idahosa and Eddy.fm

African Journals Online (AJOL)

Mrs. I.D

and economic factors have collectively acted as push factors in the migration of young ... An international migrant worker or skilled emigrant is defined by the United Nations .... 60,000 middle and high-skilled Africans emigrated from the continent ..... need to rise to the occasion as this could encourage emerging diaspora ...

High Data Rate Optical Wireless Communications Based on Ultraviolet Band

KAUST Repository

Sun, Xiaobin

2017-10-01

Optical wireless communication systems based on ultraviolet (UV)-band has a lot inherent advantages, such as low background solar radiation, low device dark noise. Besides, it also has small restrictive requirements for PAT (pointing, acquisition, and tracking) because of its high atmospheric scattering with molecules and aerosols. And these advantages are driving people to explore and utilize UV band for constructing and implementing a high-data-rate, less PAT communication links, such as diffuse-line-of-sight links (diffuse-LOS) and non-line-of-sight (NLOS). The responsivity of the photodetector at UV range is far lower than that of visible range, high power UV transmitters which can be easily modulated are under investigation. These factors make it is hard to realize a high-data-rate diffuse-LOS or NLOS UV communication links. To achieve a UV link mentioned above with current devices and modulation schemes, this thesis presents some efficient modulation schemes and available devices for the time being. Besides, a demonstration of ultraviolet-B (UVB) communication link is implemented utilizing quadrature amplitude modulation (QAM) orthogonal frequency-division multiplexing (OFDM). The demonstration is based on a 294-nm UVB-light-emitting-diode (UVB-LED) with a full-width at half-maximum (FWHM) of 9 nm, and according to the measured L-I-V curve, we set the bias voltage as 7V for maximum the ac amplitude and thus get a high signal-noise-ratio (SNR) channel, and the light output power is 190 μW with such bias voltage. Besides, there is a unique silica gel lens on top of the LED to concentrate the beam. A -3-dB bandwidth of 29 MHz was measured and a high-speed near-solar-blind communication link with a data rate of 71 Mbit/s was achieved using 8-QAM-OFDM at perfect alignment, and 23.6 Mbit/s using 2-QAM-OFDM when the angle subtended by the pointing direction of the UVB-LED and photodetector (PD) is 12 degrees, thus establishing a diffuse-line-of-sight (LOS) link

Estimating population parameters of longsnout seahorses, Hippocampus reidi (Teleostei: Syngnathidae through mark-recapture

Directory of Open Access Journals (Sweden)

Alexandre C. Siqueira

2017-12-01

Full Text Available ABSTRACT Estimating population parameters is essential for understanding the ecology of species, which ultimately helps to assess their conservation status. The seahorse Hippocampus reidi is directly exposed to anthropogenic threats along the Brazilian coast, but the species still figures as Data Deficient (DD at IUCN’s Red List. To provide better information on the ecology of this species, we studied how population parameters vary over time in a natural subtropical environment. By combing mark-recapture models for open and closed populations, we estimated abundance, survival rate, emigration probability, and capture probability. We marked 111 individuals, which showed a 1:1 sex ratio, and an average size of 10.5 cm. The population showed high survival rate, low temporary emigration probability and variable capture probability and abundance. Our models considering relevant biological criteria illuminate the relatively poorly known population ecology and life history of seahorses. It is our hope that this study inspires the use of mark-recapture methods in other populations of H. reidi in a collective effort to properly assess their conservation status.

Highly variable rates of genome rearrangements between hemiascomycetous yeast lineages.

Directory of Open Access Journals (Sweden)

2006-03-01

Full Text Available Hemiascomycete yeasts cover an evolutionary span comparable to that of the entire phylum of chordates. Since this group currently contains the largest number of complete genome sequences it presents unique opportunities to understand the evolution of genome organization in eukaryotes. We inferred rates of genome instability on all branches of a phylogenetic tree for 11 species and calculated species-specific rates of genome rearrangements. We characterized all inversion events that occurred within synteny blocks between six representatives of the different lineages. We show that the rates of macro- and microrearrangements of gene order are correlated within individual lineages but are highly variable across different lineages. The most unstable genomes correspond to the pathogenic yeasts Candida albicans and Candida glabrata. Chromosomal maps have been intensively shuffled by numerous interchromosomal rearrangements, even between species that have retained a very high physical fraction of their genomes within small synteny blocks. Despite this intensive reshuffling of gene positions, essential genes, which cluster in low recombination regions in the genome of Saccharomyces cerevisiae, tend to remain syntenic during evolution. This work reveals that the high plasticity of eukaryotic genomes results from rearrangement rates that vary between lineages but also at different evolutionary times of a given lineage.

A novel application of multi-event modeling to estimate class segregation in a highly migratory oceanic vertebrate.

Science.gov (United States)

Chapple, T K; Chambert, T; Kanive, P E; Jorgensen, S J; Rotella, J J; Anderson, S D; Carlisle, A B; Block, B A

2016-12-01

Spatial segregation of animals by class (i.e., maturity or sex) within a population due to differential rates of temporary emigration (TE) from study sites can be an important life history feature to consider in population assessment and management. However, such rates are poorly known; new quantitative approaches to address these knowledge gaps are needed. We present a novel application of multi-event models that takes advantage of two sources of detections to differentiate temporary emigration from apparent absence to quantify class segregation within a study population of double-marked (photo-identified and tagged with coded acoustic transmitters) white sharks (Carcharodon carcharias) in central California. We use this model to test if sex-specific patterns in TE result in disparate apparent capture probabilities (p o ) between male and female white sharks, which can affect the observed sex ratio. The best-supported model showed a contrasting pattern of Pr(TE) from coastal aggregation sites between sexes (for males Pr[TE] = 0.015 [95% CI = 0.00, 0.31] and Pr[TE]= 0.57 [0.40, 0.72] for females), but not maturity classes. Additionally, by accounting for Pr(TE) and imperfect detection, we were able to estimate class-specific values of true capture probability (p * ) for tagged and untagged sharks. The best-supported model identified differences between maturity classes but no difference between sexes or tagging impacts (tagged mature sharks p *  = 0.55 (0.46-0.63) and sub-adult sharks p*   = 0.36 (0.25, 0.50); and untagged mature sharks p *  = 0.50 (0.39-0.61) and sub-adults p *  = 0.18 (0.10, 0.31). Estimated sex-based differences in p o were linked to sex-specific differences in Pr(TE) but not in p * ; once the Pr(TE) is accounted for, the p * between sexes was not different. These results indicate that the observed sex ratio is not a consequence of unequal detectability and sex-specific values of Pr(TE) are important drivers of the observed male

The High Strain Rate Deformation Behavior of High Purity Magnesium and AZ31B Magnesium Alloy

Science.gov (United States)

Livescu, Veronica; Cady, Carl M.; Cerreta, Ellen K.; Henrie, Benjamin L.; Gray, George T.

The deformation in compression of pure magnesium and AZ31B magnesium alloy, both with a strong basal pole texture, has been investigated as a function of temperature, strain rate, and specimen orientation. The mechanical response of both metals is highly dependent upon the orientation of loading direction with respect to the basal pole. Specimens compressed along the basal pole direction have a high sensitivity to strain rate and temperature and display a concave down work hardening behavior. Specimens loaded perpendicularly to the basal pole have a yield stress that is relatively insensitive to strain rate and temperature and a work hardening behavior that is parabolic and then linearly upwards. Both specimen orientations display a mechanical response that is sensitive to temperature and strain rate. Post mortem characterization of the pure magnesium was conducted on a subset of specimens to determine the microstructural and textural evolution during deformation and these results are correlated with the observed work hardening behavior and strain rate sensitivities were calculated.

High-energy, high-repetition-rate picosecond pulses from a quasi-CW diode-pumped Nd:YAG system.

Science.gov (United States)

Noom, Daniel W E; Witte, Stefan; Morgenweg, Jonas; Altmann, Robert K; Eikema, Kjeld S E

2013-08-15

We report on a high-power quasi-CW pumped Nd:YAG laser system, producing 130 mJ, 64 ps pulses at 1064 nm wavelength with a repetition rate of 300 Hz. Pulses from a Nd:YVO(4) oscillator are first amplified by a regenerative amplifier to the millijoule level and then further amplified in quasi-CW diode-pumped Nd:YAG modules. Pulsed diode pumping enables a high gain at repetition rates of several hundred hertz, while keeping thermal effects manageable. Birefringence compensation and multiple thermal-lensing-compensated relay-imaging stages are used to maintain a top-hat beam profile. After frequency doubling, 75 mJ pulses are obtained at 532 nm. The intensity stability is better than 1.1%, which makes this laser an attractive pump source for a high-repetition-rate optical parametric amplification system.

A Model for High-Strain-Rate Deformation of Uranium-Niobium Alloys

Energy Technology Data Exchange (ETDEWEB)

F.L.Addessio; Q.H.Zuo; T.A.Mason; L.C.Brinson

2003-05-01

A thermodynamic approach is used to develop a framework for modeling uranium-niobium alloys under the conditions of high strain rate. Using this framework, a three-dimensional phenomenological model, which includes nonlinear elasticity (equation of state), phase transformation, crystal reorientation, rate-dependent plasticity, and porosity growth is presented. An implicit numerical technique is used to solve the evolution equations for the material state. Comparisons are made between the model and data for low-strain-rate loading and unloading as well as for heating and cooling experiments. Comparisons of the model and data also are made for low- and high-strain-rate uniaxial stress and uniaxial strain experiments. A uranium-6 weight percent niobium alloy is used in the comparisons of model and experiment.

A pulse shape discriminator with high precision of neutron and gamma ray selection at high counting rate

International Nuclear Information System (INIS)

Bialkowski, J.; Moszynski, M.; Wolski, D.

1989-01-01

A pulse shape discriminator based on the zero-crossing principle is described. Due to dc negative feedback loops stabilizing the shaping amplifier and the zero-crossing discriminator, the working of the circuit is not affected by the high counting rate and the temperature variations. The pileup rejection circuit built into the discriminator improves the quality of the n-γ separation at high counting rates. A full γ-ray rejection is obtained for a recoil energy of electrons down to 25 keV. At high counting rates the remaining γ-ray contribution is evidently due to the pileup effect which is equal to about 2% at 4x10 5 counts/s. (orig.)

Development of a cryogenic hydrogen microjet for high-intensity, high-repetition rate experiments

Science.gov (United States)

Kim, J. B.; Göde, S.; Glenzer, S. H.

2016-11-01

The advent of high-intensity, high-repetition-rate lasers has led to the need for replenishing targets of interest for high energy density sciences. We describe the design and characterization of a cryogenic microjet source, which can deliver a continuous stream of liquid hydrogen with a diameter of a few microns. The jet has been imaged at 1 μm resolution by shadowgraphy with a short pulse laser. The pointing stability has been measured at well below a mrad, for a stable free-standing filament of solid-density hydrogen.

Obstetrician perceptions of the causes of high cesarean delivery rates in Turkey.

Science.gov (United States)

Küçük, Mert

2017-07-01

To assess obstetricians' perceptions surrounding cesarean delivery rates in Turkey. The present cross-sectional descriptive study was performed between May 1 and June 30, 2016. Practicing obstetricians with contact details known by the researchers and those attending a conference in Turkey were asked to complete a self-administered questionnaire that collected demographic data and information on participants' opinions, beliefs, knowledge, attitudes, and practices related to cesarean delivery. There were 100 obstetricians who responded to the survey. Awareness of high cesarean delivery rates was reported by 96 (96%) participants and 95 (95%) respondents said they were supportive of efforts to reduce it. There were 60 (60%), 83 (83%), and 100 (100%) participants aware of associations between high cesarean delivery rates and increased maternal and infant mortality; increased risk of uterine rupture; and increased risk of placenta previa, placenta accreta, and emergency cesarean hysterectomy, respectively. The most commonly reported reason for high cesarean delivery rates was high compensation costs during medical litigation legal proceedings, reported by all 100 (100%) participants. Participants were generally aware of the risks associated with high cesarean delivery rates. The results suggest that the greatest concern among obstetricians who perform cesarean deliveries was malpractice litigation. © 2017 International Federation of Gynecology and Obstetrics.

THE AMERICAN HIGH SCHOOL GRADUATION RATE: TRENDS AND LEVELS*

Science.gov (United States)

Heckman, James J.; LaFontaine, Paul A.

2009-01-01

This paper applies a unified methodology to multiple data sets to estimate both the levels and trends in U.S. high school graduation rates. We establish that (a) the true rate is substantially lower than widely used measures; (b) it peaked in the early 1970s; (c) majority/minority differentials are substantial and have not converged for 35 years; (d) lower post-1970 rates are not solely due to increasing immigrant and minority populations; (e) our findings explain part of the slowdown in college attendance and rising college wage premiums; and (f) widening graduation differentials by gender help explain increasing male-female college attendance gaps. PMID:20625528

THE AMERICAN HIGH SCHOOL GRADUATION RATE: TRENDS AND LEVELS.

Science.gov (United States)

Heckman, James J; Lafontaine, Paul A

2010-05-01

This paper applies a unified methodology to multiple data sets to estimate both the levels and trends in U.S. high school graduation rates. We establish that (a) the true rate is substantially lower than widely used measures; (b) it peaked in the early 1970s; (c) majority/minority differentials are substantial and have not converged for 35 years; (d) lower post-1970 rates are not solely due to increasing immigrant and minority populations; (e) our findings explain part of the slowdown in college attendance and rising college wage premiums; and (f) widening graduation differentials by gender help explain increasing male-female college attendance gaps.

Precision tracking at high background rates with the ATLAS muon spectrometer

CERN Document Server

Hertenberger, Ralf; The ATLAS collaboration

2012-01-01

Since start of data taking the ATLAS muon spectrometer performs according to specification. End of this decade after the luminosity upgrade of LHC by a factor of ten the proportionally increasing background rates require the replacement of the detectors in the most forward part of the muon spectrometer to ensure high quality muon triggering and tracking at background hit rates of up to 15,kHz/cm$^2$. Square meter sized micromegas detectors together with improved thin gap trigger detectors are suggested as replacement. Micromegas detectors are intrinsically high rate capable. A single hit spatial resolution below 40,$mu$m has been shown for 250,$mu$m anode strip pitch and perpendicular incidence of high energy muons or pions. The ongoing development of large micromegas structures and their investigation under non-perpendicular incidence or in high background environments requires precise and reliable monitoring of muon tracks. A muon telescope consisting of six small micromegas works reliably and is presently ...

State-level high school completion rates: Concepts, measures, and trends.

Directory of Open Access Journals (Sweden)

John Robert Warren

2005-12-01

Full Text Available Since the mid 1970s the national rate at which incoming 9th graders have completed high school has fallen slowly but steadily; this is also true in 41 states. In 2002, about three in every four students who might have completed high school actually did so; in some states this figure is substantially lower. In this paper I review state-level measures of high school completion rates and describe and validate a new measure that reports these rates for 1975 through 2002. Existing measures based on the Current Population Survey are conceptually imperfect and statistically unreliable. Measures based on Common Core Data (CCD dropout information are unavailable for many states and have different conceptual weaknesses. Existing measures based on CCD enrollment and completion data are systematically biased by migration, changes in cohort size, and/or grade retention. The new CCD-based measure described here is considerably less biased, performs differently in empirical analyses, and gives a different picture of the dropout situation across states and over time.

Miniaturized Stretchable and High-Rate Linear Supercapacitors

OpenAIRE

Zhu, Wenjun; Zhang, Yang; Zhou, Xiaoshuang; Xu, Jiang; Liu, Zunfeng; Yuan, Ningyi; Ding, Jianning

2017-01-01

Linear stretchable supercapacitors have attracted much attention because they are well suited to applications in the rapidly expanding field of wearable electronics. However, poor conductivity of the electrode material, which limits the transfer of electrons in the axial direction of the linear supercapacitors, leads to a serious loss of capacity at high rates. To solve this problem, we use gold nanoparticles to decorate aligned multiwall carbon nanotube to fabricate stretchable linear electr...

READOUT ELECTRONICS FOR A HIGH-RATE CSC DETECTOR

International Nuclear Information System (INIS)

OCONNOR, P.; GRATCHEV, V.; KANDASAMY, A.; POLYCHRONAKOS, V.; TCHERNIATINE, V.; PARSONS, J.; SIPPACH, W.

1999-01-01

A readout system for a high-rate muon Cathode Strip Chamber (CSC) is described. The system, planned for use in the forward region of the ATLAS muon spectrometer, uses two custom CMOS integrated circuits to achieve good position resolution at a flux of up to 2,500 tracks/cm 2 /s

Mathematical modeling of high-rate Anammox UASB reactor based on granular packing patterns

International Nuclear Information System (INIS)

Tang, Chong-Jian; He, Rui; Zheng, Ping; Chai, Li-Yuan; Min, Xiao-Bo

2013-01-01

Highlights: ► A novel model was conducted to estimate volumetric nitrogen conversion rates. ► The packing patterns of the granules in Anammox reactor are investigated. ► The simple cubic packing pattern was simulated in high-rate Anammox UASB reactor. ► Operational strategies concerning sludge concentration were proposed by the modeling. -- Abstract: A novel mathematical model was developed to estimate the volumetric nitrogen conversion rates of a high-rate Anammox UASB reactor based on the packing patterns of granular sludge. A series of relationships among granular packing density, sludge concentration, hydraulic retention time and volumetric conversion rate were constructed to correlate Anammox reactor performance with granular packing patterns. It was suggested that the Anammox granules packed as the equivalent simple cubic pattern in high-rate UASB reactor with packing density of 50–55%, which not only accommodated a high concentration of sludge inside the reactor, but also provided large pore volume, thus prolonging the actual substrate conversion time. Results also indicated that it was necessary to improve Anammox reactor performance by enhancing substrate loading when sludge concentration was higher than 37.8 gVSS/L. The established model was carefully calibrated and verified, and it well simulated the performance of granule-based high-rate Anammox UASB reactor

Mathematical modeling of high-rate Anammox UASB reactor based on granular packing patterns

Energy Technology Data Exchange (ETDEWEB)

Tang, Chong-Jian, E-mail: chjtangzju@yahoo.com.cn [Department of Environmental Engineering, School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China); National Engineering Research Center for Control and Treatment of Heavy Metal Pollution, Changsha 410083 (China); He, Rui; Zheng, Ping [Department of Environmental Engineering, Zhejiang University, Zijingang Campus, Hangzhou 310058 (China); Chai, Li-Yuan; Min, Xiao-Bo [Department of Environmental Engineering, School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China); National Engineering Research Center for Control and Treatment of Heavy Metal Pollution, Changsha 410083 (China)

2013-04-15

Highlights: ► A novel model was conducted to estimate volumetric nitrogen conversion rates. ► The packing patterns of the granules in Anammox reactor are investigated. ► The simple cubic packing pattern was simulated in high-rate Anammox UASB reactor. ► Operational strategies concerning sludge concentration were proposed by the modeling. -- Abstract: A novel mathematical model was developed to estimate the volumetric nitrogen conversion rates of a high-rate Anammox UASB reactor based on the packing patterns of granular sludge. A series of relationships among granular packing density, sludge concentration, hydraulic retention time and volumetric conversion rate were constructed to correlate Anammox reactor performance with granular packing patterns. It was suggested that the Anammox granules packed as the equivalent simple cubic pattern in high-rate UASB reactor with packing density of 50–55%, which not only accommodated a high concentration of sludge inside the reactor, but also provided large pore volume, thus prolonging the actual substrate conversion time. Results also indicated that it was necessary to improve Anammox reactor performance by enhancing substrate loading when sludge concentration was higher than 37.8 gVSS/L. The established model was carefully calibrated and verified, and it well simulated the performance of granule-based high-rate Anammox UASB reactor.

Abuse resistant high rate lithium/thionyl chloride cells

Science.gov (United States)

Surprenant, J.; Snuggerud, D.

A compact, disk shaped lithium/thionyl chloride cell has been developed. The cell has a 6 Amphr capacity and is capable of high rate discharge at high voltage. Discharge data are presented over the range of 0.07 to 1.1 amperes. The cell is operable over the temperature range of -40 C to +70 C, and has a 10 year shelf life at 20 C. Safety features allow the cells to withstand fire, puncture, shock, spin, forced discharge or forced charge without dangerous reactions.

High-Pressure Limit Rate Rules for α-H Isomerization of Hydroperoxyalkylperoxy Radicals

KAUST Repository

Mohamed, Samah Y; Davis, Alexander Cory; Al Rashidi, Mariam J; Sarathy, Mani

2018-01-01

group. In this work, a combination of high level composite methods - CBS-QB3, G3 and G4 - is used to determine the high-pressure-limit rate parameters for the title reaction. Rate rules for H-migration reactions proceeding through 5-, 6-, 7- and 8

High speed surface cleaning by a high repetition rated TEA-CO2 laser

International Nuclear Information System (INIS)

Tsunemi, Akira; Hirai, Ryo; Hagiwara, Kouji; Nagasaka, Keigo; Tashiro, Hideo

1994-01-01

We demonstrated the feasibility of high speed cleaning of solid surfaces by the laser ablation technique using a TEA-CO 2 laser. The laser pulses with the repetition rate of 1 kHz were applied to paint, rust, moss and dirt attached on the surfaces. The attachments were effectively removed without the damage of bulk surfaces by the irradiation of line-focused sequential pulses with an energy of 300 mJ/pulse. A cleaning rate reached to 17 m 2 /hour for the case of paint removal from iron surfaces. (author)

Measurement of viscosity of slush at high shear rates

OpenAIRE

小林, 俊一; 川村, 公之; 津川, 圭一; 和泉, 薫; Kobayashi, Shun'ichi; Kawamura, Kimiyuki; Tugawa, Keiichi; Izumi, Kaoru

1988-01-01

Measurements of viscosity of slush were carried out using a method of flow along an inclined smooth surface in a 0℃cold room. The method was used to get the values of viscosity under high shear rates (25 and 75s^). From our experiments two important results were obtained: 1) the viscosity of slush decreases with increasing shear rates; 2) The fluid behavior is pseudoplastic that the values of non-Newtonian index of viscosity were less than unity.

Design and Development of High-Repetition-Rate Satellite Laser Ranging System

Science.gov (United States)

Choi, Eun-Jung; Bang, Seong-Cheol; Sung, Ki-Pyoung; Lim, Hyung-Chul; Jung, Chan-Gyu; Kim, In-Yeung; Choi, Jae-Seung

2015-09-01

The Accurate Ranging System for Geodetic Observation ? Mobile (ARGO-M) was successfully developed as the first Korean mobile Satellite Laser Ranging (SLR) system in 2012, and has joined in the International Laser Ranging Service (ILRS) tracking network, DAEdeoK (DAEK) station. The DAEK SLR station was approved as a validated station in April 2014, through the ILRS station ¡°data validation¡± process. The ARGO-M system is designed to enable 2 kHz laser ranging with millimeter-level precision for geodetic, remote sensing, navigation, and experimental satellites equipped with Laser Retroreflector Arrays (LRAs). In this paper, we present the design and development of a next generation high-repetition-rate SLR system for ARGO-M. The laser ranging rate up to 10 kHz is becoming an important issue in the SLR community to improve ranging precision. To implement high-repetition-rate SLR system, the High-repetition-rate SLR operation system (HSLR-10) was designed and developed using ARGO-M Range Gate Generator (A-RGG), so as to enable laser ranging from 50 Hz to 10 kHz. HSLR-10 includes both hardware controlling software and data post-processing software. This paper shows the design and development of key technologies of high-repetition-rate SLR system. The developed system was tested successfully at DAEK station and then moved to Sejong station, a new Korean SLR station, on July 1, 2015. HSLR-10 will begin normal operations at Sejong station in the near future.

Regulation and drive system for high rep-rate magnetic-pulse compressors

International Nuclear Information System (INIS)

Birx, D.L.; Cook, E.G.; Hawkins, S.; Meyers, A.; Reginato, L.L.; Schmidt, J.A.; Smith, M.W.

1982-01-01

The essentially unlimited rep-rate capability of non-linear magnetic systems has imposed strict requirements on the drive system which initiates the pulse compression. An order of magnitude increase in the rep-rates achieved by the Advanced Test Accelerator (ATA) gas blown system is not difficult to achieve in the magnetic compressor. The added requirement of having a high degree of regulation at the higher rep-rates places strict requirements on the triggerable switch for charging and de-Queing. A novel feedback technique which applies the proper bias to a magnetic core by comparing a reference voltage to the charging voltage eases considerably the regulation required to achieve low jitter in magnetic compression. The performance of the high rep-rate charging and regulation systems will be described in the following pages

High-rate capability of lithium-ion batteries after storing at elevated temperature

International Nuclear Information System (INIS)

Wu, Mao-Sung; Chiang, Pin-Chi Julia

2007-01-01

High-rate performances of a lithium-ion battery after storage at elevated temperature are investigated electrochemically by means of three-electrode system. The high-rate capability is decreased significantly after high-temperature storage. A 3 C discharge capacities after room-temperature storage and 60 o C storage are 650 and 20 mAh, respectively. Lithium-ion diffusion in lithium cobalt oxide cathode limits the battery's capacity and the results show that storage temperature changes this diffusion behavior. Transmission electron microscopy (TEM) images show that many defects are directly observed in the cathode after storage compared with the fresh cathode; the structural defects block the diffusion within the particles. Electrochemical impedance and polarization curve indicate that mass-transfer (diffusion) dominates the discharge capacity during high-rate discharge

High strain rate deformation of layered nanocomposites

Science.gov (United States)

Lee, Jae-Hwang; Veysset, David; Singer, Jonathan P.; Retsch, Markus; Saini, Gagan; Pezeril, Thomas; Nelson, Keith A.; Thomas, Edwin L.

2012-11-01

Insight into the mechanical behaviour of nanomaterials under the extreme condition of very high deformation rates and to very large strains is needed to provide improved understanding for the development of new protective materials. Applications include protection against bullets for body armour, micrometeorites for satellites, and high-speed particle impact for jet engine turbine blades. Here we use a microscopic ballistic test to report the responses of periodic glassy-rubbery layered block-copolymer nanostructures to impact from hypervelocity micron-sized silica spheres. Entire deformation fields are experimentally visualized at an exceptionally high resolution (below 10 nm) and we discover how the microstructure dissipates the impact energy via layer kinking, layer compression, extreme chain conformational flattening, domain fragmentation and segmental mixing to form a liquid phase. Orientation-dependent experiments show that the dissipation can be enhanced by 30% by proper orientation of the layers.

High strain rate deformation of layered nanocomposites.

Science.gov (United States)

Lee, Jae-Hwang; Veysset, David; Singer, Jonathan P; Retsch, Markus; Saini, Gagan; Pezeril, Thomas; Nelson, Keith A; Thomas, Edwin L

2012-01-01

Insight into the mechanical behaviour of nanomaterials under the extreme condition of very high deformation rates and to very large strains is needed to provide improved understanding for the development of new protective materials. Applications include protection against bullets for body armour, micrometeorites for satellites, and high-speed particle impact for jet engine turbine blades. Here we use a microscopic ballistic test to report the responses of periodic glassy-rubbery layered block-copolymer nanostructures to impact from hypervelocity micron-sized silica spheres. Entire deformation fields are experimentally visualized at an exceptionally high resolution (below 10 nm) and we discover how the microstructure dissipates the impact energy via layer kinking, layer compression, extreme chain conformational flattening, domain fragmentation and segmental mixing to form a liquid phase. Orientation-dependent experiments show that the dissipation can be enhanced by 30% by proper orientation of the layers.

Radiation shielding and dose rate distribution for the building of the high dose rate accelerator

International Nuclear Information System (INIS)

Matsuda, Koji; Takagaki, Torao; Nakase, Yoshiaki; Nakai, Yohta.

1984-03-01

A high dose rate electron accelerator was established at Osaka Laboratory for Radiation Chemistry, Takasaki Establishment, JAERI in the fiscal year of 1975. This report shows the fundamental concept for the radiation shielding of the accelerator building and the results of their calculations which were evaluated through the model experiments. After the construction of the building, the leak radiation was measured in order to evaluate the calculating method of radiation shielding. Dose rate distribution of X-rays was also measured in the whole area of the irradiation room as a data base. (author)

High-rate tensile behavior of steel fiber-reinforced concrete for nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Kim, Jung Jin; Park, Gi-Joon [Department of Civil and Environmental Engineering, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747 (Korea, Republic of); Kim, Dong Joo, E-mail: djkim75@sejong.ac.kr [Department of Civil and Environmental Engineering, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747 (Korea, Republic of); Moon, Jae Heum; Lee, Jang Hwa [Korea Institute of Construction Technology, 2311 Daewha-Dong, Ilsan-Gu, Goyang-Si, Gyeonggi-Do 411-712 (Korea, Republic of)

2014-01-15

Highlights: • The final goal is to develop a fiber reinforced concrete for containment buildings. • High rate tensile behavior of FRC was investigated. • Strain energy frame impact machine was used for tensile impact tests. • Different rate sensitivity of FRC was found according to the type fiber. • Adding more fibers by increasing S/a is positive for higher impact resistance of FRC. -- Abstract: The direct tensile behavior of fiber-reinforced concrete (FRC) at high strain rates were investigated for their potential to enhance the resistance of the containment building of nuclear power plants (NPPs) against aircraft impact. Two types of deformed steel, hooked (H) and twisted (T) fibers were employed. To improve the tensile resistance of FRCs even at higher rates by adding more fibers, the mixture of concrete was modified by either increasing the sand-to-coarse aggregate ratio or decreasing the maximum size of coarse aggregate. All FRC specimens produced two to six times greater tensile strength and one to five times higher toughness at high strain rates (4–53 s{sup −1}) than those at a static rate (0.000167 s{sup −1}). T-fiber generally produced higher tensile strength and toughness than H-fiber at both static and high rates. Although both fibers showed favorable rate sensitivity, T-fiber produced much greater enhancement, at higher strain rates, in tensile strength and slightly lower enhancement in toughness than H-fiber. As the maximum size of coarse aggregate decreased from 19 to 5 mm, the tensile strength and toughness of FRCs with T-fibers noticeably increased at both static and high strain rates.

Abuse resistant high rate lithium/thionyl chloride cells

Energy Technology Data Exchange (ETDEWEB)

Surprenant, J.; Snuggerud, D.

1982-08-01

A compact, disc shaped lithium/thionyl chloride cell has been developed by Altus Corporation. The cell has a 6 Amphr capacity and is capable of high rate discharge at high voltage. Discharge data is presented over the range of 0.07 to 1.1 Amperes. The cell is operable over the temperature range of -40/sup 0/C to +70/sup 0/C, and has a 10 year shelf life at 20/sup 0/C. Safety features allow the cells to withstand fire, puncture, shock, spin, forced discharge or forced charge without dangerous reactions.

Positive predictive value of device-detected atrial high-rate episodes at different rates and durations

DEFF Research Database (Denmark)

Kaufman, Elizabeth S; Israel, Carsten W; Nair, Girish M

2012-01-01

BACKGROUND: Pacemakers can automatically identify and catalog atrial high-rate episodes (AHREs). While most AHREs represent true atrial tachyarrhythmia/atrial fibrillation (AT/AF), a review of stored electrograms suggests that a substantial proportion do not. As AHREs may lead to the initiation o...

Carbon nanotubes/cobalt sulfide composites as potential high-rate and high-efficiency supercapacitors

Science.gov (United States)

Chen, Chia-Ying; Shih, Zih-Yu; Yang, Zusing; Chang, Huan-Tsung

2012-10-01

We have prepared carbon nanotube (CNT)/cobalt sulfide (CoS) composites from cobalt nitrate, thioacetamide, and CNTs in the presence of poly(vinylpyrrolidone). CNT/CoS composites are deposited onto fluorine-doped tin oxide glass substrates and then subjected to simple annealing at 300 °C for 0.5 h to fabricate CNT/CoS electrodes. Data collected from Raman spectroscopy, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and d-spacing reveal the changes in the CoS structures and crystalline lattices after annealing. Cyclic voltammetry results reveal that the annealed CNT/CoS composite electrodes yield values of 2140 ± 90 and 1370 ± 50 F g-1 for specific capacitance at scan rates of 10 and 100 mV s-1, respectively. To the best of our knowledge, the annealed CNT/CoS composite electrodes provide higher specific capacitance relative to other reported ones at a scan rate of 100 mV s-1. CNT/CoS composite electrodes yield a power density of 62.4 kW kg-1 at a constant discharge current density of 217.4 A g-1. With such a high-rate capacity and power density, CNT/CoS composite supercapacitors demonstrate great potential as efficient energy storage devices.

A review of reaction rates in high temperature air

Science.gov (United States)

Park, Chul

1989-01-01

The existing experimental data on the rate coefficients for the chemical reactions in nonequilibrium high temperature air are reviewed and collated, and a selected set of such values is recommended for use in hypersonic flow calculations. For the reactions of neutral species, the recommended values are chosen from the experimental data that existed mostly prior to 1970, and are slightly different from those used previously. For the reactions involving ions, the recommended rate coefficients are newly chosen from the experimental data obtained more recently. The reacting environment is assumed to lack thermal equilibrium, and the rate coefficients are expressed as a function of the controlling temperature, incorporating the recent multitemperature reaction concept.

Solid State Track Recorder fission rate measurements at high neutron fluence and high temperature

International Nuclear Information System (INIS)

Ruddy, F.H.; Roberts, J.H.; Gold, R.

1985-01-01

Solid State Track Recorder (SSTR) techniques have been used to measure 239-Pu, 235-U, and 237-Np fission rates for total neutron fluences approaching 5 x 10 17 n/cm 2 at temperatures in the range 680 to 830 0 F. Natural quartz crystal SSTRs were used to withstand the high temperature environment and ultra low-mass fissionable deposits of the three isotopes were required to yield scannable track densities at the high neutron fluences. The results of these high temperature, high neutron fluence measurements are reported

Optimization and phase matching of fiber-laser-driven high-order harmonic generation at high repetition rate.

Science.gov (United States)

Cabasse, Amélie; Machinet, Guillaume; Dubrouil, Antoine; Cormier, Eric; Constant, Eric

2012-11-15

High-repetition-rate sources are very attractive for high-order harmonic generation (HHG). However, due to their pulse characteristics (low energy, long duration), those systems require a tight focusing geometry to achieve the necessary intensity to generate harmonics. In this Letter, we investigate theoretically and experimentally the optimization of HHG in this geometry, to maximize the extreme UV (XUV) photon flux and improve the conversion efficiency. We analyze the influence of atomic gas media (Ar, Kr, or Xe), gas pressure, and interaction geometries (a gas jet and a finite and a semi-infinite gas cell). Numerical simulations allow us to define optimal conditions for HHG in this tight focusing regime and to observe the signature of on-axis phase matching. These conditions are implemented experimentally using a high-repetition-rate Yb-doped fiber laser system. We achieve optimization of emission with a recorded XUV photon flux of 4.5×10(12) photons/s generated in Xe at 100 kHz repetition rate.

Behavior of quenched and tempered steels under high strain rate compression loading

International Nuclear Information System (INIS)

Meyer, L.W.; Seifert, K.; Abdel-Malek, S.

1997-01-01

Two quenched and tempered steels were tested under compression loading at strain rates of ε = 2.10 2 s -1 and ε = 2.10 3 s -1 . By applying the thermal activation theory, the flow stress at very high strain rates of 10 5 to 10 6 s -1 is derived from low temperature and high strain rate tests. Dynamic true stress - true strain behaviour presents, that stress increases with increasing strain until a maximum, then it decreases. Because of the adiabatic process under dynamic loading the maximum flow stress will occur at a lower strain if the strain rate is increased. Considering strain rate, strain hardening, strain rate hardening and strain softening, a constitutive equation with different additive terms is successfully used to describe the behaviour of material under dynamic compression loading. Results are compared with other models of constitutive equations. (orig.)

High Strain Rate and Shock-Induced Deformation in Metals

Science.gov (United States)

Ravelo, Ramon

2012-02-01

Large-scale non-equilibrium molecular Dynamics (MD) simulations are now commonly used to study material deformation at high strain rates (10^9-10^12 s-1). They can provide detailed information-- such as defect morphology, dislocation densities, and temperature and stress profiles, unavailable or hard to measure experimentally. Computational studies of shock-induced plasticity and melting in fcc and bcc single, mono-crystal metals, exhibit generic characteristics: high elastic limits, large directional anisotropies in the yield stress and pre-melting much below the equilibrium melt temperature for shock wave propagation along specific crystallographic directions. These generic features in the response of single crystals subjected to high strain rates of deformation can be explained from the changes in the energy landscape of the uniaxially compressed crystal lattice. For time scales relevant to dynamic shock loading, the directional-dependence of the yield strength in single crystals is shown to be due to the onset of instabilities in elastic-wave propagation velocities. The elastic-plastic transition threshold can accurately be predicted by a wave-propagation stability analysis. These strain-induced instabilities create incipient defect structures, which can be quite different from the ones, which characterize the long-time, asymptotic state of the compressed solid. With increase compression and strain rate, plastic deformation via extended defects gives way to amorphization associated with the loss in shear rigidity along specific deformation paths. The hot amorphous or (super-cooled liquid) metal re-crystallizes at rates, which depend on the temperature difference between the amorphous solid and the equilibrium melt line. This plastic-amorphous transition threshold can be computed from shear-waves stability analyses. Examples from selected fcc and bcc metals will be presented employing semi-empirical potentials of the embedded atom method (EAM) type as well as

The effects of climate change and land-use change on demographic rates and population viability.

Science.gov (United States)

Selwood, Katherine E; McGeoch, Melodie A; Mac Nally, Ralph

2015-08-01

Understanding the processes that lead to species extinctions is vital for lessening pressures on biodiversity. While species diversity, presence and abundance are most commonly used to measure the effects of human pressures, demographic responses give a more proximal indication of how pressures affect population viability and contribute to extinction risk. We reviewed how demographic rates are affected by the major anthropogenic pressures, changed landscape condition caused by human land use, and climate change. We synthesized the results of 147 empirical studies to compare the relative effect size of climate and landscape condition on birth, death, immigration and emigration rates in plant and animal populations. While changed landscape condition is recognized as the major driver of species declines and losses worldwide, we found that, on average, climate variables had equally strong effects on demographic rates in plant and animal populations. This is significant given that the pressures of climate change will continue to intensify in coming decades. The effects of climate change on some populations may be underestimated because changes in climate conditions during critical windows of species life cycles may have disproportionate effects on demographic rates. The combined pressures of land-use change and climate change may result in species declines and extinctions occurring faster than otherwise predicted, particularly if their effects are multiplicative. © 2014 The Authors. Biological Reviews © 2014 Cambridge Philosophical Society.

Increased effects of machining damage in beryllium observed at high strain rates

International Nuclear Information System (INIS)

Beitscher, S.; Brewer, A.W.; Corle, R.R.

1980-01-01

Tensile tests at both low and high strain rates, and also impact shear tests, were performed on a weldable grade powder-source beryllium. Impact energies increased by a factor of 2 to 3 from the as-machined level after etching or annealing. Similar increases in the ductility from machining damage removal were observed from the tensile data at the higher strain rate (10 s -1 ) while an insignificant increase in elongation was measured at the lower strain rate (10 -4 s -1 ). High strain-rate tests appear to be more sensitive and reliable for evaluating machining practice and damage removal methods for beryllium components subjected to sudden loads. 2 tables

Operation of high rate microstrip gas chambers

CERN Document Server

Barr, A J; Bouclier, Roger; Capéans-Garrido, M; Dominik, Wojciech; Manzin, G; Million, Gilbert; Hoch, M; Ropelewski, Leszek; Sauli, Fabio; Sharma, A

1996-01-01

We describe recent measurements carried out in well controlled and reproducible conditions to help understanding the factors affecting the short and long term behaviour of Microstrip Gas Chambers. Special care has been taken concerning the gas purity and choice of materials used in the system and for the detectors construction. Detectors built on glasses with surface resistivity in the range $10^{13}-10^{15} \\Omega/\\Box$ have shown satisfactory performance as they do not show charging-up process at high rate and stand the large doses required for the future high luminosity experiments (~10 mC·cm-1·yr-1). Concerning the lifetime measurements, it has been observed that chambers manufactured on high-resistivity glass are far more susceptible of suffering ageing than detectors made on low resistivity, electron-conducting supports, independently of the metal used for the artwork (chromium or gold) at least in clean gas conditions. The successfully operation in the laboratory of detectors manufactured on diamond-...

Distinct IL-7 signaling in recent thymic emigrants versus mature naïve T cells controls T-cell homeostasis.

Science.gov (United States)

Kim, Hye Kyung; Waickman, Adam T; Castro, Ehydel; Flomerfelt, Francis A; Hawk, Nga V; Kapoor, Veena; Telford, William G; Gress, Ronald E

2016-07-01

IL-7 is essential for T-cell survival but its availability is limited in vivo. Consequently, all peripheral T cells, including recent thymic emigrants (RTEs) are constantly competing for IL-7 to survive. RTEs are required to replenish TCR diversity and rejuvenate the peripheral T-cell pool. However, it remains unknown how RTEs successfully compete with resident mature T cells for IL-7. Moreover, RTEs express low levels of IL-7 receptors, presumably rendering them even less competitive. Here, we show that, surprisingly, RTEs are more responsive to IL-7 than mature naïve T cells as demonstrated by markedly increased STAT5 phosphorylation upon IL-7 stimulation. Nonetheless, adoptive transfer of RTE cells into lymphopenic host mice resulted in slower IL-7-induced homeostatic proliferation and diminished expansion compared to naïve donor T cells. Mechanistically, we found that IL-7 signaling in RTEs preferentially upregulated expression of Bcl-2, which is anti-apoptotic but also anti-proliferative. In contrast, naïve T cells showed diminished Bcl-2 induction but greater proliferative response to IL-7. Collectively, these data indicate that IL-7 responsiveness in RTE is designed to maximize survival at the expense of reduced proliferation, consistent with RTE serving as a subpopulation of T cells rich in diversity but not in frequency. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Linkages among climate change, crop yields and Mexico-US cross-border migration.

Science.gov (United States)

Feng, Shuaizhang; Krueger, Alan B; Oppenheimer, Michael

2010-08-10

Climate change is expected to cause mass human migration, including immigration across international borders. This study quantitatively examines the linkages among variations in climate, agricultural yields, and people's migration responses by using an instrumental variables approach. Our method allows us to identify the relationship between crop yields and migration without explicitly controlling for all other confounding factors. Using state-level data from Mexico, we find a significant effect of climate-driven changes in crop yields on the rate of emigration to the United States. The estimated semielasticity of emigration with respect to crop yields is approximately -0.2, i.e., a 10% reduction in crop yields would lead an additional 2% of the population to emigrate. We then use the estimated semielasticity to explore the potential magnitude of future emigration. Depending on the warming scenarios used and adaptation levels assumed, with other factors held constant, by approximately the year 2080, climate change is estimated to induce 1.4 to 6.7 million adult Mexicans (or 2% to 10% of the current population aged 15-65 y) to emigrate as a result of declines in agricultural productivity alone. Although the results cannot be mechanically extrapolated to other areas and time periods, our findings are significant from a global perspective given that many regions, especially developing countries, are expected to experience significant declines in agricultural yields as a result of projected warming.

Problems and solutions in high-rate multichannel hybrid photodiode design The CMS experience

CERN Document Server

Cushman, P B

2002-01-01

The unique conditions of the CMS experiment (4 T magnetic field, restricted access, high neutron radiation, and 25-ns bunch-crossings) necessitated the development of a new type of high-rate multichannel hybrid photodiode for the tile/fiber hadronic calorimeter. New complexities arose in the push toward high-rate operation, necessitating design changes in the diode structure and surface treatment. The product is now capable of high-rate operation with low crosstalk and leakage current. Lifetime studies of high-voltage behavior, total charge, and irradiation have shown that the tubes will survive the ten years of CMS running with only a few percent change in gain and manageable leakage current rise. (13 refs).

High rate, fast timing Glass RPC for the high $\\eta$ CMS muon detectors

CERN Document Server

INSPIRE-00185093; Lagarde, François; Laktineh, Imad; Buridon, Victor; Chen, Xiushan; Combaret, Christophe; Eynard, Alexis; Germani, Lionel; Grenier, Gerald; Mathez, Hervé; Mirabito, Laurent; Petrukhin, Alexei; Steen, Arnaud; Tromeur, William; Wang, Yi; Gong, A.; Moreau, Nathalie; de la Taille, Christophe; Dulucq, Fréderic

2017-02-11

The HL-LHC phase is designed to increase by an order of magnitude the amount of data to be collected by the LHC experiments. To achieve this goal in a reasonable time scale the instantaneous luminosity would also increase by an order of magnitude up to $6 \\cdot 10^{34}$ cm$^{-2}$s$^{-1}$. The region of the forward muon spectrometer ($|\\eta| > 1.6$) is not equipped with RPC stations. The increase of the expected particles rate up to 2 kHz/cm$^2$ ( including a safety factor 3 ) motivates the installation of RPC chambers to guarantee redundancy with the CSC chambers already present. The actual RPC technology of CMS cannot sustain the expected background level. A new generation Glass-RPC (GRPC) using low resistivity glass (LR) is proposed to equip at least the two most far away of the four high eta muon stations of CMS. The design of small size prototypes and the studies of their performances under high rate particles flux is presented.

Time-Efficient High-Rate Data Flooding in One-Dimensional Acoustic Underwater Sensor Networks

Directory of Open Access Journals (Sweden)

Jae Kyun Kwon

2015-10-01

Full Text Available Because underwater communication environments have poor characteristics, such as severe attenuation, large propagation delays and narrow bandwidths, data is normally transmitted at low rates through acoustic waves. On the other hand, as high traffic has recently been required in diverse areas, high rate transmission has become necessary. In this paper, transmission/reception timing schemes that maximize the time axis use efficiency to improve the resource efficiency for high rate transmission are proposed. The excellence of the proposed scheme is identified by examining the power distributions by node, rate bounds, power levels depending on the rates and number of nodes, and network split gains through mathematical analysis and numerical results. In addition, the simulation results show that the proposed scheme outperforms the existing packet train method.

Evolution of high tooth replacement rates in sauropod dinosaurs.

Science.gov (United States)

D'Emic, Michael D; Whitlock, John A; Smith, Kathlyn M; Fisher, Daniel C; Wilson, Jeffrey A

2013-01-01

Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates. We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined by counting daily incremental lines in dentin. Tooth replacement rate is calculated as the difference between the number of days recorded in successive replacement teeth. Each tooth family in Camarasaurus has a maximum of three replacement teeth, whereas each Diplodocus tooth family has up to five. Tooth formation times are about 1.7 times longer in Camarasaurus than in Diplodocus (315 vs. 185 days). Average tooth replacement rate in Camarasaurus is about one tooth every 62 days versus about one tooth every 35 days in Diplodocus. Despite slower tooth replacement rates in Camarasaurus, the volumetric rate of Camarasaurus tooth replacement is 10 times faster than in Diplodocus because of its substantially greater tooth volumes. A novel method to estimate replacement rate was developed and applied to several other sauropodomorphs that we were not able to thin section. Differences in tooth replacement rate among sauropodomorphs likely reflect disparate feeding strategies and/or food choices, which would have facilitated the coexistence of these gigantic herbivores in one ecosystem. Early neosauropods are characterized by high tooth replacement rates (despite their large tooth size), and derived titanosaurs and diplodocoids independently evolved the highest known tooth replacement rates among archosaurs.

Evolution of high tooth replacement rates in sauropod dinosaurs.

Directory of Open Access Journals (Sweden)

Michael D D'Emic

Full Text Available BACKGROUND: Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates. METHODOLOGY/PRINCIPAL FINDINGS: We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined by counting daily incremental lines in dentin. Tooth replacement rate is calculated as the difference between the number of days recorded in successive replacement teeth. Each tooth family in Camarasaurus has a maximum of three replacement teeth, whereas each Diplodocus tooth family has up to five. Tooth formation times are about 1.7 times longer in Camarasaurus than in Diplodocus (315 vs. 185 days. Average tooth replacement rate in Camarasaurus is about one tooth every 62 days versus about one tooth every 35 days in Diplodocus. Despite slower tooth replacement rates in Camarasaurus, the volumetric rate of Camarasaurus tooth replacement is 10 times faster than in Diplodocus because of its substantially greater tooth volumes. A novel method to estimate replacement rate was developed and applied to several other sauropodomorphs that we were not able to thin section. CONCLUSIONS/SIGNIFICANCE: Differences in tooth replacement rate among sauropodomorphs likely reflect disparate feeding strategies and/or food choices, which would have facilitated the coexistence of these gigantic herbivores in one ecosystem. Early neosauropods are characterized by high tooth replacement rates (despite their large tooth size, and derived titanosaurs and

Brachytherapy for early oral tongue cancer. Low dose rate to high dose rate

International Nuclear Information System (INIS)

Yamazaki, Hideya; Inoue, Takehiro; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Inoue, Toshihiko; Furukawa, Souhei; Kakimoto, Naoya

2003-01-01

To examine the compatibility of low dose rate (LDR) with high dose rate (HDR) brachytherapy, we reviewed 399 patients with early oral tongue cancer (T1-2N0M0) treated solely by brachytherapy at Osaka University Hospital between 1967 and 1999. For patients in the LDR group (n=341), the treatment sources consisted of Ir-192 pin for 227 patients (1973-1996; irradiated dose, 61-85 Gy; median, 70 Gy), Ra-226 needle for 113 patients (1967-1986; 55-93 Gy; median, 70 Gy). Ra-226 and Ir-192 were combined for one patient. Ir-192 HDR (microSelectron-HDR) was used for 58 patients in the HDR group (1991-present; 48-60 Gy; median, 60 Gy). LDR implantations were performed via oral and HDR via a submental/submandibular approach. The dose rates at the reference point for the LDR group were 0.30 to 0.8 Gy/h, and for the HDR group 1.0 to 3.4 Gy/min. The patients in the HDR group received a total dose of 48-60 Gy (8-10 fractions) during one week. Two fractions were administered per day (at least a 6-h interval). The 3- and 5-year local control rates for patients in the LDR group were 85% and 80%, respectively, and those in the HDR group were both 84%. HDR brachytherapy showed the same lymph-node control rate as did LDR brachytherapy (67% at 5 years). HDR brachytherapy achieved the same locoregional result as did LDR brachytherapy. A converting factor of 0.86 is applicable for HDR in the treatment of early oral tongue cancer. (author)

Programmable High-Rate Multi-Mission Receiver for Space Communications, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — Current and upcoming NASA space links require both highly reliable low-rate communications links supporting critical TT&C, ranging and voice services and highly...

Programmable High-Rate Multi-Mission Receiver for Space Communications, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Current and upcoming NASA space links require both highly reliable low-rate communications links supporting critical TT&C, ranging and voice services and highly...

Demographic trends in the Lodz region and their implications for seniors 50+

Directory of Open Access Journals (Sweden)

Jolanta Woźnica

2014-12-01

Simultaneously, due to declining birth rates, prolongation of human life and emigration, especially young people, are progressing aging of the population, including labor resources. It is already a serious problem is the high proportion of economically inactive older people , and also low rates of labor force participation and employment. Shaped so the situation there is a need to take action at the regional level, aimed at creating conditions for continuation of work for persons having a retirement age through measures to improve the functioning of the working environment of older people.

A novel VLSI processor for high-rate, high resolution spectroscopy

CERN Document Server

Pullia, Antonio; Gatti, E; Longoni, A; Buttler, W

2000-01-01

A novel time-variant VLSI shaper amplifier, suitable for multi-anode Silicon Drift Detectors or other multi-element solid-state X-ray detection systems, is proposed. The new read-out scheme has been conceived for demanding applications with synchrotron light sources, such as X-ray holography or EXAFS, where both high count-rates and high-energy resolutions are required. The circuit is of the linear time-variant class, accepts randomly distributed events and features: a finite-width (1-10 mu s) quasi-optimal weight function, an ultra-low-level energy discrimination (approx 150 eV), and a full compatibility for monolithic integration in CMOS technology. Its impulse response has a staircase-like shape, but the weight function (which is in general different from the impulse response in time-variant systems) is quasi trapezoidal. The operation principles of the new scheme as well as the first experimental results obtained with a prototype of the circuit are presented and discussed in the work.

Matching of experimental and statistical-model thermonuclear reaction rates at high temperatures

International Nuclear Information System (INIS)

Newton, J. R.; Longland, R.; Iliadis, C.

2008-01-01

We address the problem of extrapolating experimental thermonuclear reaction rates toward high stellar temperatures (T>1 GK) by using statistical model (Hauser-Feshbach) results. Reliable reaction rates at such temperatures are required for studies of advanced stellar burning stages, supernovae, and x-ray bursts. Generally accepted methods are based on the concept of a Gamow peak. We follow recent ideas that emphasized the fundamental shortcomings of the Gamow peak concept for narrow resonances at high stellar temperatures. Our new method defines the effective thermonuclear energy range (ETER) by using the 8th, 50th, and 92nd percentiles of the cumulative distribution of fractional resonant reaction rate contributions. This definition is unambiguous and has a straightforward probability interpretation. The ETER is used to define a temperature at which Hauser-Feshbach rates can be matched to experimental rates. This matching temperature is usually much higher compared to previous estimates that employed the Gamow peak concept. We suggest that an increased matching temperature provides more reliable extrapolated reaction rates since Hauser-Feshbach results are more trustwhorthy the higher the temperature. Our ideas are applied to 21 (p,γ), (p,α), and (α,γ) reactions on A=20-40 target nuclei. For many of the cases studied here, our extrapolated reaction rates at high temperatures differ significantly from those obtained using the Gamow peak concept

Iodine laser of high efficiency and fast repetition rate

Energy Technology Data Exchange (ETDEWEB)

Hohla, K; Witte, K J

1976-07-01

The scaling laws of an iodine laser of high efficiency and fast repetition rate are reported. The laser is pumped with a new kind of low pressure Hg-UV-lamps which convert 32% of the electrical input in UV-light in the absorption band of the iodine laser and which can be fired up to 100 Hz. Details of a 10 kJ/1 nsec system as dimensions, energy density, repetition rate, flow velocity, gas composition and gas pressure and the overall efficiency are given which is expected to be about 2%.

WO{sub 3-x} rate at Au rate at MnO{sub 2} core-shell nanowires on carbon fabric for high-performance flexible supercapacitors

Energy Technology Data Exchange (ETDEWEB)

Lu, Xihong; Zhai, Teng [Wuhan National Laboratory for Optoelectronics (WNLO), College of Optoelectronic Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan (China); School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou (China); Zhang, Xianghui; Shen, Yongqi; Yuan, Longyan; Hu, Bin; Gao, Yihua; Zhou, Jun [Wuhan National Laboratory for Optoelectronics (WNLO), College of Optoelectronic Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan (China); Gong, Li; Chen, Jian [Instrumental Analysis and Research Center, Sun Yat-sen University, Guangzhou (China); Tong, Yexiang [School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou (China); Wang, Zhong Lin [Wuhan National Laboratory for Optoelectronics (WNLO), College of Optoelectronic Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan (China); School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia (United States)

2012-02-14

WO{sub 3-x} rate at Au rate at MnO{sub 2} core-shell nanowires (NWs) are synthesized on a flexible carbon fabric and show outstanding electrochemical performance in supercapacitors such as high specific capacitance, good cyclic stability, high energy density, and high power density. These results suggest that the WO{sub 3-x} rate at Au rate at MnO{sub 2} NWs have promising potential for use in high-performance flexible supercapacitors. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Multistate modelling extended by behavioural rules: An application to migration.

Science.gov (United States)

Klabunde, Anna; Zinn, Sabine; Willekens, Frans; Leuchter, Matthias

2017-10-01

We propose to extend demographic multistate models by adding a behavioural element: behavioural rules explain intentions and thus transitions. Our framework is inspired by the Theory of Planned Behaviour. We exemplify our approach with a model of migration from Senegal to France. Model parameters are determined using empirical data where available. Parameters for which no empirical correspondence exists are determined by calibration. Age- and period-specific migration rates are used for model validation. Our approach adds to the toolkit of demographic projection by allowing for shocks and social influence, which alter behaviour in non-linear ways, while sticking to the general framework of multistate modelling. Our simulations yield that higher income growth in Senegal leads to higher emigration rates in the medium term, while a decrease in fertility yields lower emigration rates.

Laryngeal High-Speed Videoendoscopy: Sensitivity of Objective Parameters towards Recording Frame Rate

Directory of Open Access Journals (Sweden)

Anne Schützenberger

2016-01-01

Full Text Available The current use of laryngeal high-speed videoendoscopy in clinic settings involves subjective visual assessment of vocal fold vibratory characteristics. However, objective quantification of vocal fold vibrations for evidence-based diagnosis and therapy is desired, and objective parameters assessing laryngeal dynamics have therefore been suggested. This study investigated the sensitivity of the objective parameters and their dependence on recording frame rate. A total of 300 endoscopic high-speed videos with recording frame rates between 1000 and 15 000 fps were analyzed for a vocally healthy female subject during sustained phonation. Twenty parameters, representing laryngeal dynamics, were computed. Four different parameter characteristics were found: parameters showing no change with increasing frame rate; parameters changing up to a certain frame rate, but then remaining constant; parameters remaining constant within a particular range of recording frame rates; and parameters changing with nearly every frame rate. The results suggest that (1 parameter values are influenced by recording frame rates and different parameters have varying sensitivities to recording frame rate; (2 normative values should be determined based on recording frame rates; and (3 the typically used recording frame rate of 4000 fps seems to be too low to distinguish accurately certain characteristics of the human phonation process in detail.

Development of a 300 Amp-hr high rate lithium thionyl chloride cell

Science.gov (United States)

Boyle, Gerard H.

1991-01-01

The development of a high-rate lithium thionyl chloride cylindrical cell with parallel plate electrodes is discussed. The development was divided into three phases: phase 1, a 150 Amp/hour low rate (1 mA/sq cm) design; phase 2, a 25 Amp/hour high rate (5 mA/sq cm) design; and phase 3, a 300 Amp/hour high rate (5 mA/sq cm) design. The basic design is the same for all three cells. The electrodes are perpendicular to the axis of the cylinder. Multiple electrodes are bussed up the side of the cylinder, 180 deg apart allowing excellent anode and cathode utilization. It is a lithium limited design with excess electrolyte. The cathode is Shawinigan or Gulf Acetylene black with no catalyst. The electrolyte is 1.8 Molar lithium tetrachloroaluminate (LiAlCl4) in thionyl chloride. All cell cases are 304L Stainless Steel with a BS&B burst disc.

Development of a 300 Amp-hr high rate lithium thionyl chloride cell

Science.gov (United States)

Boyle, Gerard H.

1991-05-01

The development of a high-rate lithium thionyl chloride cylindrical cell with parallel plate electrodes is discussed. The development was divided into three phases: phase 1, a 150 Amp/hour low rate (1 mA/sq cm) design; phase 2, a 25 Amp/hour high rate (5 mA/sq cm) design; and phase 3, a 300 Amp/hour high rate (5 mA/sq cm) design. The basic design is the same for all three cells. The electrodes are perpendicular to the axis of the cylinder. Multiple electrodes are bussed up the side of the cylinder, 180 deg apart allowing excellent anode and cathode utilization. It is a lithium limited design with excess electrolyte. The cathode is Shawinigan or Gulf Acetylene black with no catalyst. The electrolyte is 1.8 Molar lithium tetrachloroaluminate (LiAlCl4) in thionyl chloride. All cell cases are 304L Stainless Steel with a BS&B burst disc.

Phase-Separated Polyaniline/Graphene Composite Electrodes for High-Rate Electrochemical Supercapacitors.

Science.gov (United States)

Wu, Jifeng; Zhang, Qin'e; Zhou, An'an; Huang, Zhifeng; Bai, Hua; Li, Lei

2016-12-01

Polyaniline/graphene hydrogel composites with a macroscopically phase-separated structure are prepared. The composites show high specific capacitance and excellent rate performance. Further investigation demonstrates that polyaniline inside the graphene hydrogel has low rate performance, thus a phase-separated structure, in which polyaniline is mainly outside the graphene hydrogel matrix, can enhance the rate performance of the composites. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Game-Theoretic Rate-Distortion-Complexity Optimization of High Efficiency Video Coding

DEFF Research Database (Denmark)

Ukhanova, Ann; Milani, Simone; Forchhammer, Søren

2013-01-01

profiles in order to tailor the computational load to the different hardware and power-supply resources of devices. In this work, we focus on optimizing the quantization parameter and partition depth in HEVC via a game-theoretic approach. The proposed rate control strategy alone provides 0.2 dB improvement......This paper presents an algorithm for rate-distortioncomplexity optimization for the emerging High Efficiency Video Coding (HEVC) standard, whose high computational requirements urge the need for low-complexity optimization algorithms. Optimization approaches need to specify different complexity...

Development of amplifier and shaper for high-rate MWPC

International Nuclear Information System (INIS)

Kamiji, Ichinori; Nanjo, Hajime; Kawasaki, Naoki; Maeda, Yosuke; Naito, Daichi; Seki, Shigeto; Nakagiri, Kota; Sasao, Noboru; Nomura, Tadashi

2015-01-01

A multi-wire proportional chamber (MWPC) will be used as an in-beam charged particle detector for the J-PARC E14 (KOTO) experiment. The maximum counting rate of the MWPC is expected to be up to 1 MHz per channel due to the high neutron and photon flux, expected to be 1 GHz for the 30 x 30 cm"2 area. An amplifier to cope with such high counting-rate is required. We developed a prototype of such amplifier, which has a charge preamplifier with the integration time of 3 ns and a pulse shaping part with three pole-zero cancellation networks. The shaper reduced the characteristic long tail lasting tens of microseconds in the signal of MWPC to 150 ns. Its performance has been tested by using a single-channel MWPC which has almost the same geometrical parameters as the MWPC to be installed in the KOTO experiment. (author)

High-rep-rate Thomson scattering for LHD

Science.gov (United States)

den Hartog, D. J.; Borchardt, M. T.; Holly, D. J.; Schmitz, O.; Yasuhara, R.; Yamada, I.; Funaba, H.; Osakabe, M.; Morisaki, T.

2017-10-01

A high-rep-rate pulse-burst laser system is being built for the LHD Thomson scattering (TS) diagnostic. This laser will have two operating scenarios, a fast-burst sequence of 15 kHz rep rate for at least 15 ms, and a slow-burst sequence of 1 kHz for at least 50 ms. There will be substantial flexibility in burst sequences for tailoring to experimental requirements. This new laser system will operate alongside the existing lasers in the LHD TS diagnostic, and will use the same beamline. This increase in temporal resolution capability complements the high spatial resolution (144 points) of the LHD TS diagnostic, providing unique measurement capability unmatched on any other fusion experiment. The new pulse-burst laser is a straightforward application of technology developed at UW-Madison, consisting of a Nd:YAG laser head with modular flashlamp drive units and a customized control system. Variable pulse-width drive of the flashlamps is accomplished by IGBT (insulated gate bipolar transistor) switching of electrolytic capacitor banks. Direct control of the laser Pockels cell drive enables optimal pulse energy extraction, producing >1.5 J q-switched pulses with 20 ns FWHM. Burst operation of this laser system will be used to capture fast time evolution of the electron temperature and density profiles during events such as ELMs, RMP perturbations, and various MHD modes. This work is supported by the U. S. Department of Energy and the National Institute for Fusion Science (Japan).

Patterns and processes of habitat-specific demographic variability in exploited marine species

NARCIS (Netherlands)

Vasconcelos, R.P.; Eggleston, D.B.; Pape, le O.; Tulp, I.Y.M.

2014-01-01

Population dynamics are governed by four demographic rates: births, deaths, immigration, and emigration. Variation in these rates and processes underlying such variation can be used to prioritize habitat conservation and restoration as well as to parameterize models that predict habitat-specific

High-Rate Field Demonstration of Large-Alphabet Quantum Key Distribution

Science.gov (United States)

2016-10-12

count rate of Bob’s detectors. In this detector-limited regime , it is advantageous to increase M to encode as much information as possible in each...High- rate field demonstration of large-alphabet quantum key distribution Catherine Lee,1, 2 Darius Bunandar,1 Zheshen Zhang,1 Gregory R. Steinbrecher...October 12, 2016) 2 Quantum key distribution (QKD) enables secure symmetric key exchange for information-theoretically secure com- munication via one-time

Potassium vapor assisted preparation of highly graphitized hierarchical porous carbon for high rate performance supercapacitors

Science.gov (United States)

Liu, Zheng; Zeng, Ying; Tang, Qunli; Hu, Aiping; Xiao, Kuikui; Zhang, Shiying; Deng, Weina; Fan, Binbin; Zhu, Yanfei; Chen, Xiaohua

2017-09-01

Ultrahigh graphitized carbon microspheres with rich hierarchical pores (AGHPCM-1) have been successfully synthesized through the one-step activation-carbonization strategy (OACS) with porous sulfonated poly-divinylbenzene as the carbon precursor, iron as the hard template and catalyst, and potassium hydroxide (KOH) as activation agent. Through the XRD, TEM, Raman and BET analysis, AGHPCM-1 shows very high graphitization degree and rich micro-, meso- and macro-pores. More importantly, the mechanism for KOH to improve the graphitization degree of carbon materials in OACS has been illustrated by the thermodynamical theory. The tremendous heat releasing from the reaction between the catalyst precursor of Fe2O3 and potassium vapor plays a key role in the formation of graphitized carbon. It may provide a general direction to prepare highly graphitized porous carbon at a moderate temperature. Integrating the advantages of high graphitization degree and rich hierarchical porous structure, the AGHPCM-1 exhibits an excellent rate performance with a response to up to the high current density of 150 A g-1 and high scan rate of 2000 mV s-1. No obvious capacitance decay can be observed after 10000 charge/discharge cycles even at the high current density of 20 A g-1.

High rate of teenage pregnancy and sexually transmitted infections ...

African Journals Online (AJOL)

There is increased in teenage pregnancy despite the presence of dual protection practice and health care awareness programmes related to health and sexuality education in South Africa. The present study explores the underlying causes of high teenage pregnancy and sexually transmitted diseases rates, including HIV ...

Decay rate of the false vacuum at high tempratures

International Nuclear Information System (INIS)

Eboli, O.J.P.; Marques, G.C.

1984-01-01

Within the semiclassical approach, the high temperaure behaviour of the decay rate of the metastable vacuum in Field Theory is investigated. It is shown that, contrarily to what has been proposed in the literature, the pre-exponential factor exhibits a nontrivial dependence on the temperature. Furthermore, this dependence is such that at very high temperatures it is as important as the exponential factor and consequently it spoils many conclusions drawn up to now on Cosmological Phase Transitions. (Author) [pt

Femtosecond Ti:sapphire cryogenic amplifier with high gain and MHz repetition rate

DEFF Research Database (Denmark)

Dantan, Aurelien Romain; Laurat, Julien; Ourjoumtsev, Alexei

2007-01-01

We demonstrate high gain amplification of 160-femtosecond pulses in a compact double-pass cryogenic Ti:sapphire amplifier. The setup involves a negative GVD mirrors recompression stage, and operates with a repetition rate between 0.2 and 4 MHz with a continuous pump laser. Amplification factors a...... as high as 17 and 320 nJ Fourier-limited pulses are obtained at a 800 kHz repetition rate....

Demo : an embedded vision system for high frame rate visual servoing

NARCIS (Netherlands)

Ye, Z.; He, Y.; Pieters, R.S.; Mesman, B.; Corporaal, H.; Jonker, P.P.

2011-01-01

The frame rate of commercial off-the-shelf industrial cameras is breaking the threshold of 1000 frames-per-second, the sample rate required in high performance motion control systems. On the one hand, it enables computer vision as a cost-effective feedback source; On the other hand, it imposes

High dose rate brachytherapy for oral cancer.

Science.gov (United States)

Yamazaki, Hideya; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Furukawa, Souhei; Koizumi, Masahiko; Ogawa, Kazuhiko

2013-01-01

Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer.

High Rate Plastic Deformation and Failure of Tungsten-Sintered Metals

National Research Council Canada - National Science Library

Bjerke, Todd

2004-01-01

The competition between plastic deformation and brittle fracture during high rate loading of a tungsten-sintered metal is examined through impact experiments, post-experiment microscopy, and numerical simulation...

Energy absorption at high strain rate of glass fiber reinforced mortars

Directory of Open Access Journals (Sweden)

Fenu Luigi

2015-01-01

Full Text Available In this paper, the dynamic behaviour of cement mortars reinforced with glass fibers was studied. The influence of the addition of glass fibers on energy absorption and tensile strength at high strain-rate was investigated. Static tests in compression, in tension and in bending were first performed. Dynamic tests by means of a Modified Hopkinson Bar were then carried out in order to investigate how glass fibers affected energy absorption and tensile strength at high strain-rate of the fiber reinforced mortar. The Dynamic Increase Factor (DIF was finally evaluated.

Characteristics of highly rated leadership in nursing homes using item response theory.

Science.gov (United States)

Backman, Annica; Sjögren, Karin; Lindkvist, Marie; Lövheim, Hugo; Edvardsson, David

2017-12-01

To identify characteristics of highly rated leadership in nursing homes. An ageing population entails fundamental social, economic and organizational challenges for future aged care. Knowledge is limited of both specific leadership behaviours and organizational and managerial characteristics which have an impact on the leadership of contemporary nursing home care. Cross-sectional. From 290 municipalities, 60 were randomly selected and 35 agreed to participate, providing a sample of 3605 direct-care staff employed in 169 Swedish nursing homes. The staff assessed their managers' (n = 191) leadership behaviours using the Leadership Behaviour Questionnaire. Data were collected from November 2013 - September 2014, and the study was completed in November 2016. A two-parameter item response theory approach and regression analyses were used to identify specific characteristics of highly rated leadership. Five specific behaviours of highly rated nursing home leadership were identified; that the manager: experiments with new ideas; controls work closely; relies on subordinates; coaches and gives direct feedback; and handles conflicts constructively. The regression analyses revealed that managers with social work backgrounds and privately run homes were significantly associated with higher leadership ratings. This study highlights the five most important leadership behaviours that characterize those nursing home managers rated highest in terms of leadership. Managers in privately run nursing homes and managers with social work backgrounds were associated with higher leadership ratings. Further work is needed to explore these behaviours and factors predictive of higher leadership ratings. © 2017 John Wiley & Sons Ltd.

Efficient high-peak-power and high-repetition-rate eye-safe laser using an intracavity KTP OPO

International Nuclear Information System (INIS)

Guo, J; Jiao, Z X; Wang, B; He, G Y

2015-01-01

An efficient high-peak-power and high-repetition-rate intracavity KTP optical parametric oscillator pumped by a Q-switched Nd:YVO 4 laser is demonstrated. We achieved 1.5 W output power of 1.5 μm at 10 kHz repetition rate with the pulse duration of 6 ns. The maximum peak power of 25 kW and the maximum pulse energy of 150 μJ have been obtained. The maximum conversion efficiency of 9.5% is achieved with respect to a laser diode power of 10.5 W. (paper)

Complication rates of ostomy surgery are high and vary significantly between hospitals.

Science.gov (United States)

Sheetz, Kyle H; Waits, Seth A; Krell, Robert W; Morris, Arden M; Englesbe, Michael J; Mullard, Andrew; Campbell, Darrell A; Hendren, Samantha

2014-05-01

Ostomy surgery is common and has traditionally been associated with high rates of morbidity and mortality, suggesting an important target for quality improvement. The purpose of this work was to evaluate the variation in outcomes after ostomy creation surgery within Michigan to identify targets for quality improvement. This was a retrospective cohort study. The study took place within the 34-hospital Michigan Surgical Quality Collaborative. Patients included were those undergoing ostomy creation surgery between 2006 and 2011. We evaluated hospital morbidity and mortality rates after risk adjustment (age, comorbidities, emergency vs elective, and procedure type). A total of 4250 patients underwent ostomy creation surgery; 3866 procedures (91.0%) were open and 384 (9.0%) were laparoscopic. Unadjusted morbidity and mortality rates were 43.9% and 10.7%. Unadjusted morbidity rates for specific procedures ranged from 32.7% for ostomy-creation-only procedures to 47.8% for Hartmann procedures. Risk-adjusted morbidity rates varied significantly between hospitals, ranging from 31.2% (95% CI, 18.4-43.9) to 60.8% (95% CI, 48.9-72.6). There were 5 statistically significant high-outlier hospitals and 3 statistically significant low-outlier hospitals for risk-adjusted morbidity. The pattern of complication types was similar between high- and low-outlier hospitals. Case volume, operative duration, and use of laparoscopic surgery did not explain the variation in morbidity rates across hospitals. This work was limited by its retrospective study design, by unmeasured variation in case severity, and by our inability to differentiate between colostomies and ileostomies because of the use of Current Procedural Terminology codes. Morbidity and mortality rates for modern ostomy surgery are high. Although this type of surgery has received little attention in healthcare policy, these data reveal that it is both common and uncommonly morbid. Variation in hospital performance provides an

High rate, fast timing Glass RPC for the high ${\\eta}$ CMS muon detectors

CERN Document Server

Lagarde, F.; Laktineh, I.; Buridon, V.; Chen, X.; Combaret, C.; Eynard, A.; Germani, L.; Grenier, G.; Mathez, H.; Mirabito, L.; Petrukhin, A.; Steen, A.; Tromeur, W.; Wang, Y.; Gong, A.; Moreau, N.; de la Taille, C.; Dulucq, F.; Cimmino, A.; Crucy, S.; Fagot, A.; Gul, M.; Rios, A.A.O.; Tytgat, M.; Zaganidis, N.; Aly, S.; Assran, Y.; Radi, A.; Sayed, A.; Singh, G.; Abbrescia, M.; Iaselli, G.; Maggi, M.; Pugliese, G.; Verwilligen, P.; Van Doninck, W.F.; Colafranceschi, S.; Sharmag, A.; Benussi, L.; Bianco, S.; Piccolo, D.; Primavera, F.; Bhatnagar, V.; Kumari, R.; Mehta, A.; Singh, J.; Ahmad, A.; Ahmed, W.; Asghar, M.I.; Awan, I.M.; Hoorani, R.; Muhammad, S.; Shahzad, H.; Shah, M.A.; Cho, S.W.; Choi, S.Y.; Hong, B.; Kang, M.H.; Lee, K.S.; Lim, J.H.; Park, S.K.; Kim, M.S.; Carpinteyro Bernardino, S.; Pedraza, I.; Uribe Estradam, C.; Carrillo Moreno, S.; Vazquez Valencia, F.; Pant, L.M.; Buontempo, S.; Cavallo, N.; Esposito, M.; Fabozzi, F.; Lanza, G.; Orso, I.; Lista, L.; Meola, S.; Merola, M.; Paolucci, P.; Thyssen, F.; Braghieri, A.; Magnani, A.; Montagna, P.; Riccardi, C.; Salvini, P.; Vai, I.; Vitulo, P.; Ban, Y.; Qian, S.J.; Choi, M.; Choi, Y.; Goh, J.; Kim, D.; Aleksandrov, A.; Hadjiiska, R.; Iaydjiev, P.; Rodozov, M.; Stoykova, S.; Sultanov, G.; Vutova, M.; Dimitrov, A.; Litov, L.; Pavlov, B.; Petkov, P.; Bagaturia, I.; Lomidze, D.; Avila, C.; Cabrera, A.; Sanabria, J.C.; Crotty, I.; Vaitkus, J.

2016-09-09

The HL-LHC phase is designed to increase by an order of magnitude the amount of data to be collected by the LHC experiments. To achieve this goal in a reasonable time scale the instantaneous luminosity would also increase by an order of magnitude up to $6.10^{34} cm^{-2} s^{-1}$ . The region of the forward muon spectrometer ($|{\\eta}| > 1.6$) is not equipped with RPC stations. The increase of the expected particles rate up to $2 kHz/cm^{2}$ (including a safety factor 3) motivates the installation of RPC chambers to guarantee redundancy with the CSC chambers already present. The actual RPC technology of CMS cannot sustain the expected background level. The new technology that will be chosen should have a high rate capability and provides a good spatial and timing resolution. A new generation of Glass-RPC (GRPC) using low-resistivity (LR) glass is proposed to equip at least the two most far away of the four high ${\\eta}$ muon stations of CMS. First the design of small size prototypes and studies of their perfor...

High-rate multi-GNSS: what does it mean to seismology?

Science.gov (United States)

Geng, J.

2017-12-01

GNSS precise point positioning (PPP) is capable of measuring centimeter-level positions epoch by epoch at a single station, and is thus treasured in tsunami/earthquake early warning where static displacements in the near field are critical to rapidly and reliably determining the magnitude of destructive events. However, most operational real-time PPP systems at present rely on only GPS data. The deficiency of such systems is that the high reliability and availability of precise displacements cannot be maintained continuously in real time, which is however a crucial requirement for disaster resistance and response. Multi-GNSS, including GLONASS, BeiDou, Galileo and QZSS other than only GPS, can be a solution to this problem because much more satellites per epoch (e.g. 30-40) will be available. In this case, positioning failure due to data loss or blunders can be minimized, and on the other hand, positioning initializations can be accelerated to a great extent since the satellite geometry for each epoch will be enhanced enormously. We established a prototype real-time multi-GNSS PPP service based on Asia-Pacific real-time network which can collect and stream high-rate data from all five navigation systems above. We estimated high-rate satellite clock corrections and enabled undifferenced ambiguity fixing for multi-GNSS, which therefore ensures high availability and reliability of precise displacement estimates in contrast to GPS-only systems. We will report how we can benefit from multi-GNSS for seismology, especially the noise characteristics of high-rate and sub-daily displacements. We will also use storm surge loading events to demonstrate the contribution of multi-GNSS to sub-daily transient signals.

NCLB Implementation Report: State Approaches for Calculating High School Graduation Rates.

Science.gov (United States)

Swanson, Christopher B.

This review investigated the state accountability Workbooks provisionally approved and publicly reported by the U.S. Department of Education (DOE) as of June 2003. These documents were obtained from the DOE Web site. This report examines state definitions of high school graduation rates and strategies for constructing graduation rate indicators. A…

High capacity and high rate capability of nitrogen-doped porous hollow carbon spheres for capacitive deionization

International Nuclear Information System (INIS)

Zhao, Shanshan; Yan, Tingting; Wang, Hui; Chen, Guorong; Huang, Lei; Zhang, Jianping; Shi, Liyi; Zhang, Dengsong

2016-01-01

Graphical abstract: - Highlights: • The nitrogen-doped porous hollow carbon spheres were prepared. • The obtained materials have a good capacitive deionization performance. • The electrodes show high salt adsorption rate and good regeneration performance. - Abstract: In this work, nitrogen-doped porous hollow carbon spheres (N-PHCS) were well prepared by using polystyrene (PS) spheres as hard templates and dopamine hydrochloride as carbon and nitrogen sources. Field emission scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images demonstrate that the N-PHCS have a uniform, spherical and hollow structure. Nitrogen adsorption–desorption analysis shows that the N-PHCS have a high specific area of 512 m 2 /g. X-ray photoelectron spectroscopy result reveals that the nitrogen doping amount is 2.92%. The hollow and porous structure and effective nitrogen doping can contribute to large accessible surface area, efficient ion transport and good conductivity. In the electrochemical tests, we can conclude that the N-PHCS have a high specific capacitance value, a good stability and low inner resistance. The N-PHCS electrodes present a high salt adsorption capacity of 12.95 mg/g at a cell voltage of 1.4 V with a flow rate of 40 mL/min in a 500 mg/L NaCl aqueous solution. Moreover, the N-PHCS electrodes show high salt adsorption rate and good regeneration performance in the CDI process. With high surface specific area and effective nitrogen doping, the N-PHCS is promising to the CDI and other electrochemical applications.

High capacity and high rate capability of nitrogen-doped porous hollow carbon spheres for capacitive deionization

Energy Technology Data Exchange (ETDEWEB)

Zhao, Shanshan; Yan, Tingting; Wang, Hui; Chen, Guorong; Huang, Lei; Zhang, Jianping; Shi, Liyi; Zhang, Dengsong, E-mail: dszhang@shu.edu.cn

2016-04-30

Graphical abstract: - Highlights: • The nitrogen-doped porous hollow carbon spheres were prepared. • The obtained materials have a good capacitive deionization performance. • The electrodes show high salt adsorption rate and good regeneration performance. - Abstract: In this work, nitrogen-doped porous hollow carbon spheres (N-PHCS) were well prepared by using polystyrene (PS) spheres as hard templates and dopamine hydrochloride as carbon and nitrogen sources. Field emission scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images demonstrate that the N-PHCS have a uniform, spherical and hollow structure. Nitrogen adsorption–desorption analysis shows that the N-PHCS have a high specific area of 512 m{sup 2}/g. X-ray photoelectron spectroscopy result reveals that the nitrogen doping amount is 2.92%. The hollow and porous structure and effective nitrogen doping can contribute to large accessible surface area, efficient ion transport and good conductivity. In the electrochemical tests, we can conclude that the N-PHCS have a high specific capacitance value, a good stability and low inner resistance. The N-PHCS electrodes present a high salt adsorption capacity of 12.95 mg/g at a cell voltage of 1.4 V with a flow rate of 40 mL/min in a 500 mg/L NaCl aqueous solution. Moreover, the N-PHCS electrodes show high salt adsorption rate and good regeneration performance in the CDI process. With high surface specific area and effective nitrogen doping, the N-PHCS is promising to the CDI and other electrochemical applications.

High rate amplifier-digitizer system for liquid argon calorimeters

International Nuclear Information System (INIS)

Droege, T.F.; Lobkowicz, F.; Fukushima, Y.

1978-01-01

A low-cost charge amplifier for a liquid argon photon detector and a new method for pulse height analysis are described. This scheme is suitable for high-energy photon detection with high counting rate. Samples of preamplifer output are taken just before and just after the arrival of the charge from the detector. The difference of these samples provides a stable pedestal and rejects low frequency noise. Short two-pulse resolving time (approximately equal to 200ns) is achieved. 6 refs

A constitutive model for particulate-reinforced titanium matrix composites subjected to high strain rates and high temperatures

Directory of Open Access Journals (Sweden)

Song Wei-Dong

2013-01-01

Full Text Available Quasi-static and dynamic tension tests were conducted to study the mechanical properties of particulate-reinforced titanium matrix composites at strain rates ranging from 0.0001/s to 1000/s and at temperatures ranging from 20 °C to 650 °C Based on the experimental results, a constitutive model, which considers the effects of strain rate and temperature on hot deformation behavior, was proposed for particulate-reinforced titanium matrix composites subjected to high strain rates and high temperatures by using Zener-Hollomon equations including Arrhenius terms. All the material constants used in the model were identified by fitting Zener-Hollomon equations against the experimental results. By comparison of theoretical predictions presented by the model with experimental results, a good agreement was achieved, which indicates that this constitutive model can give an accurate and precise estimate for high temperature flow stress for the studied titanium matrix composites and can be used for numerical simulations of hot deformation behavior of the composites.

Emigração e desenvolvimento da previdência social em Portugal Emigration and the development of social welfare in Portugal

Directory of Open Access Journals (Sweden)

Victor Pereira

2009-09-01

Full Text Available Este artigo analisa a política social do final dos anos 60 e inícios dos anos 70. Demonstra que o alargamento da previdência social corresponde a uma tentativa de ajustamento do governo face à emigração que se iniciou no fim da década de 50. Este alargamento resultou também da acção no seio do Estado de uma corrente de altos funcionários inspirados pela doutrina social da Igreja renovada pelo Vaticano II, da inserção de alguns agentes administrativos nas comunidades epistémicas internacionais ligadas às políticas sociais e de uma tentativa de legitimação do poder de Marcelo Caetano.This article analyses social policy in the 1960s and early 1970s. It shows that the expansion of the social welfare system was an attempt by the government to adapt to the emigration which began in the late 1950s. Other factors behind the expansion of the system were measures taken within the government by a group of senior officials who were inspired by the new life given to the Church's social doctrines arising from Vatican II, the membership of some administrative officials in international communities of experts on social policy, and the attempt to legitimize the Marcelo Caetano regime.

Analysis of heating effect on the process of high deposition rate microcrystalline silicon

International Nuclear Information System (INIS)

Xiao-Dan, Zhang; He, Zhang; Chang-Chun, Wei; Jian, Sun; Guo-Fu, Hou; Shao-Zhen, Xiong; Xin-Hua, Geng; Ying, Zhao

2010-01-01

A possible heating effect on the process of high deposition rate microcrystalline silicon has been studied. It includes the discharge time-accumulating heating effect, discharge power, inter-electrode distance, and total gas flow rate induced heating effect. It is found that the heating effects mentioned above are in some ways quite similar to and in other ways very different from each other. However, all of them will directly or indirectly cause the increase of the substrate surface temperature during the process of depositing microcrystalline silicon thin films, which will affect the properties of the materials with increasing time. This phenomenon is very serious for the high deposition rate of microcrystalline silicon thin films because of the high input power and the relatively small inter-electrode distance needed. Through analysis of the heating effects occurring in the process of depositing microcrystalline silicon, it is proposed that the discharge power and the heating temperature should be as low as possible, and the total gas flow rate and the inter-electrode distance should be suitable so that device-grade high quality deposition rate microcrystalline silicon thin films can be fabricated

Highly efficient, versatile, self-Q-switched, high-repetition-rate microchip laser generating Ince–Gaussian modes for optical trapping

Energy Technology Data Exchange (ETDEWEB)

Jun Dong; Yu He; Xiao Zhou; Shengchuang Bai [Department of Electronics Engineering, School of Information Science and Engineering, Xiamen, 361005 (China)

2016-03-31

Lasers operating in the Ince-Gaussian (IG) mode have potential applications for optical manipulation of microparticles and formation of optical vortices, as well as for optical trapping and optical tweezers. Versatile, self-Q-switched, high-peak-power, high-repetition-rate Cr, Nd:YAG microchip lasers operating in the IG mode are implemented under tilted, tightly focused laser-diode pumping. An average output power of over 2 W is obtained at an absorbed pump power of 6.4 W. The highest optical-to-optical efficiency of 33.2% is achieved at an absorbed pump power of 3.9 W. Laser pulses with a pulse energy of 7.5 μJ, pulse width of 3.5 ns and peak power of over 2 kW are obtained. A repetition rate up to 335 kHz is reached at an absorbed pump power of 5.8 W. Highly efficient, versatile, IG-mode lasers with a high repetition rate and a high peak power ensure a better flexibility in particle manipulation and optical trapping. (control of laser radiation parameters)

Treatment of carcinoma of uterine cervix with high-dose-rate intracavitary irradiation using Ralstron

International Nuclear Information System (INIS)

Suh, C.O.; Kim, G.E.; Loh, J.J.K.

1988-01-01

From May 1979 through December 1981, a total of 530 patients with carcinoma of the uterine cervix were treated with radiation therapy with curative intent. Of the 530 patients, 365 were treated with a high-dose-rate remote-controlled afterloading system (RALS) using a cobalt source, and 165 patients received a low dose rate using a radium source. External pelvic irradiation with a total of 40-50 Gy to the whole pelvis followed by intracavitary radiation (ICR) with a total dose of 30-39 Gy in ten to 13 fractions to point A was the treatment protocol. ICR was given three times a week with a dose of 3 Gy per fraction. Five-year actuarial survival rate with high-dose-rate ICR by stage was as follows: stage I:82.7% (N = 19) stage II:69.6% (N = 184), and stage III:52.2% (N = 156). The above results were comparable with those with conventional low-dose-rate ICR treatment, and late complications were far less. The application of high-dose-rate ICR was technically simple and easily performed on an outpatient basis without anesthesia, and the patients tolerated it very well. Radiation exposure to personnel was virtually none as compared with that of low-dose-rate ICR. Within a given period of time, more patients can be treated with high-dose-rate ICR because of the short treatment time. The authors therefore conclude that high-dose-rate ICR is suitable for a cancer center where a large number of patients are to be treated

MDT Performance in a High Rate Background Environment

CERN Document Server

Aleksa, Martin; Hessey, N P; Riegler, W

1998-01-01

A Cs137 gamma source with different lead filters in the SPS beam-line X5 has been used to simulate the ATLAS background radiation. This note shows the impact of high background rates on the MDT efficiency and resolution for three kinds of pulse shaping and compares the results with GARFIELD simulations. Furthermore it explains how the performance can be improved by time slewing corrections and double track separation.

Least reliable bits coding (LRBC) for high data rate satellite communications

Science.gov (United States)

Vanderaar, Mark; Budinger, James; Wagner, Paul

1992-01-01

LRBC, a bandwidth efficient multilevel/multistage block-coded modulation technique, is analyzed. LRBC uses simple multilevel component codes that provide increased error protection on increasingly unreliable modulated bits in order to maintain an overall high code rate that increases spectral efficiency. Soft-decision multistage decoding is used to make decisions on unprotected bits through corrections made on more protected bits. Analytical expressions and tight performance bounds are used to show that LRBC can achieve increased spectral efficiency and maintain equivalent or better power efficiency compared to that of BPSK. The relative simplicity of Galois field algebra vs the Viterbi algorithm and the availability of high-speed commercial VLSI for block codes indicates that LRBC using block codes is a desirable method for high data rate implementations.

Influence of Cooling Rate in High-Temperature Area on Hardening of Deposited High-Cutting Chrome-Tungsten Metal

OpenAIRE

Malushin, N. N.; Valuev, Denis Viktorovich; Valueva, Anna Vladimirovna; Serikbol, A.; Borovikov, I. F.

2015-01-01

The authors study the influence of cooling rate in high-temperature area for thermal cycle of high-cutting chrome-tungsten metal weld deposit on the processes of carbide phase merging and austenite grain growth for the purpose of providing high hardness of deposited metal (HRC 64-66).

High-rate lithium thionyl-chloride battery development

Energy Technology Data Exchange (ETDEWEB)

Cieslak, W.R.; Weigand, D.E.

1993-12-31

We have developed a lithium thionyl-chloride cell for use in a high rate battery application to provide power for a missile computer and stage separation detonators. The battery pack contains 20 high surface area ``DD`` cells wired in a series-parallel configuration to supply a nominal 28 volts with a continuous draw of 20 amperes. The load profile also requires six squib firing pulses of one second duration at a 20 ampere peak. Performance and safety of the cells were optimized in a ``D`` cell configuration before progressing to the longer ``DD` cell. Active surface area in the ``D`` cell is 735 cm{sup 2}, and 1650 cm{sup 2} in the ``DD`` cell. The design includes 1.5M LiAlCl{sub 4}/SOCl{sub 2} electrolyte, a cathode blend of Shawinigan Acetylene Black and Cabot Black Pearls 2000 carbons, Scimat ETFE separator, and photoetched current collectors.

The Impact of High School Exit Exams on Graduation Rates and Achievement

Science.gov (United States)

Caves, Katherine; Balestra, Simone

2018-01-01

The authors examined the short- and long-term effects of high school exit exams (HSEEs) on graduation rates and achievement using an interrupted time series approach. There is a positive overall effect of HSEE introduction for graduation rate trends, which is heterogeneous over time. HSEEs have a negative impact on graduation rates in the year of…

High dose rate brachytherapy for oral cancer

International Nuclear Information System (INIS)

Yamazaki, Hideya; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Koizumi, Masahiko; Ogawa, Kazuhiko; Furukawa, Souhei

2013-01-01

Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer. (author)

Research of narrow pulse width, high repetition rate, high output power fiber lasers for deep space exploration

Science.gov (United States)

Tang, Yan-feng; Li, Hong-zuo; Wang, Yan; Hao, Zi-qiang; Xiao, Dong-Ya

2013-08-01

As human beings expand the research in unknown areas constantly, the deep space exploration has become a hot research topic all over the world. According to the long distance and large amount of information transmission characteristics of deep space exploration, the space laser communication is the preferred mode because it has the advantages of concentrated energy, good security, and large information capacity and interference immunity. In a variety of laser source, fibre-optical pulse laser has become an important communication source in deep space laser communication system because of its small size, light weight and large power. For fiber lasers, to solve the contradiction between the high repetition rate and the peak value power is an important scientific problem. General Q technology is difficult to obtain a shorter pulse widths, This paper presents a DFB semiconductor laser integrated with Electro-absorption modulator to realize the narrow pulse width, high repetition rate of the seed source, and then using a two-cascaded high gain fiber amplifier as amplification mean, to realize the fibre-optical pulse laser with pulse width 3ns, pulse frequency 200kHz and peak power 1kW. According to the space laser atmospheric transmission window, the wavelength selects for 1.06um. It is adopted that full fibre technology to make seed source and amplification, pumping source and amplification of free-space coupled into fiber-coupled way. It can overcome that fibre lasers are vulnerable to changes in external conditions such as vibration, temperature drift and other factors affect, improving long-term stability. The fiber lasers can be modulated by PPM mode, to realize high rate modulation, because of its peak power, high transmission rate, narrow pulse width, high frequency stability, all technical indexes meet the requirements of the exploration of deep space communication technology.

High-voltage power supply of ND6 portable dose rate meter

International Nuclear Information System (INIS)

Wang Shaling

2001-01-01

Portable dose rate meter needs to be equipped with a set of high-voltage power supply which is supplied by batteries and has characteristic of high quality, low energy expense and small size. The author introduces application conditions and performance guide line

Review: Recharge rates and chemistry beneath playas of the High Plains aquifer, USA

Science.gov (United States)

Gurdak, Jason J.; Roe, Cassia D.

2010-12-01

Playas are ephemeral, closed-basin wetlands that are hypothesized as an important source of recharge to the High Plains aquifer in central USA. The ephemeral nature of playas, low regional recharge rates, and a strong reliance on groundwater from the High Plains aquifer has prompted many questions regarding the contribution and quality of recharge from playas to the High Plains aquifer. As a result, there has been considerable scientific debate about the potential for water to infiltrate the relatively impermeable playa floors, travel through the unsaturated zone sediments that are tens of meters thick, and subsequently recharge the High Plains aquifer. This critical review examines previously published studies on the processes that control recharge rates and chemistry beneath playas. Reported recharge rates beneath playas range from less than 1.0 to more than 500 mm/yr and are generally 1-2 orders of magnitude higher than recharge rates beneath interplaya settings. Most studies support the conceptual model that playas are important zones of recharge to the High Plains aquifer and are not strictly evaporative pans. The major findings of this review provide science-based implications for management of playas and groundwater resources of the High Plains aquifer and directions for future research.

Results in patients treated with high-dose-rate interstitial brachytherapy for oral tongue cancer

International Nuclear Information System (INIS)

Yamamoto, Michinori; Shirane, Makoto; Ueda, Tsutomu; Miyahara, Nobuyuki

2006-01-01

Eight patients were treated with high-dose-rate interstitial brachytherapy for oral tongue cancer between September 2000 and August 2004. The patient distribution was 1 T1, 5 T2, 1 T3, and 1 T4a. Patients received 50-60 Gy in 10 fractions over seven days with high-dose-rate brachytherapy. Six of the eight patients were treated with a combination of external beam radiotherapy (20-30 Gy) and interstitial brachytherapy. The two-year primary local control rate was 83% for initial case. High-dose-rate brachytherapy was performed safely even for an aged person, and was a useful treatment modality for oral tongue cancer. (author)

Influence of Cooling Rate in High-Temperature Area on Hardening of Deposited High-Cutting Chrome-Tungsten Metal

International Nuclear Information System (INIS)

Malushin, N N; Valuev, D V; Valueva, A V; Serikbol, A; Borovikov, I F

2015-01-01

The authors study the influence of cooling rate in high-temperature area for thermal cycle of high-cutting chrome-tungsten metal weld deposit on the processes of carbide phase merging and austenite grain growth for the purpose of providing high hardness of deposited metal (HRC 64-66). (paper)

Automated Production of High Rep Rate Foam Targets

Science.gov (United States)

Hall, F.; Spindloe, C.; Haddock, D.; Tolley, M.; Nazarov, W.

2016-04-01

Manufacturing low density targets in the numbers needed for high rep rate experiments is highly challenging. This report summarises advances from manual production to semiautomated and the improvements that follow both in terms of production time and target uniformity. The production process is described and shown to be improved by the integration of an xyz robot with dispensing capabilities. Results are obtained from manual and semiautomated production runs and compared. The variance in the foam thickness is reduced significantly which should decrease experimental variation due to target parameters and could allow for whole batches to be characterised by the measurement of a few samples. The work applies to both foil backed and free standing foam targets.

Experimental characterization and modelling of UO2 mechanical behaviour at high temperatures and high strain rates

International Nuclear Information System (INIS)

Salvo, Maxime

2014-01-01

The aim of this work is to characterize and model the mechanical behavior of uranium dioxide (UO 2 ) during a Reactivity Initiated Accident (RIA). The fuel loading during a RIA is characterized by high strain rates (up to 1/s) and high temperatures (1000 C - 2500 C). Two types of UO 2 pellets (commercial and high density) were therefore tested in compression with prescribed displacement rates (0.1 to 100 mm/min corresponding to strain rates of 10 -4 - 10 -1 /s) and temperatures (1100 C - 1350 C - 1550 C et 1700 C). Experimental results (geometry, yield stress and microstructure) allowed us to define a hyperbolic sine creep law and a Drucker-Prager criterion with associated plasticity, in order to model grain boundaries fragmentation at the macroscopic scale. Finite Element Simulations of these tests and of more than 200 creep tests were used to assess the model response to a wide range of temperatures (1100 C - 1700 C) and strain rates (10 -9 /s - 10 -1 /s). Finally, a constitutive law called L3F was developed for UO 2 by adding to the previous model irradiation creep and tensile macroscopic cracking. The L3F law was then introduced in the 1.5D scheme of the fuel performance code ALCYONE-RIA to simulate the REP-Na tests performed in the experimental reactor CABRI. Simulation results are in good agreement with post tests examinations. (author) [fr

Low nitrous oxide production through nitrifier-denitrification in intermittent-feed high-rate nitritation reactors

DEFF Research Database (Denmark)

Su, Qingxian; Ma, Chun; Domingo-Felez, Carlos

2017-01-01

Nitrous oxide (N2O) production from autotrophic nitrogen conversion processes, especially nitritation systems, can be significant, requires understanding and calls for mitigation. In this study, the rates and pathways of N2O production were quantified in two lab-scale sequencing batch reactors...... to maintain high nitritation efficiency and high nitritation rates at 20-26 °C over a period of ∼300 days. Even at the high nitritation efficiencies, net N2O production was low (∼2% of the oxidized ammonium). Net N2O production rates transiently increased with a rise in pH after each feeding, suggesting...... operated with intermittent feeding and demonstrating long-term and high-rate nitritation. The resulting reactor biomass was highly enriched in ammonia-oxidizing bacteria, and converted ∼93 ± 14% of the oxidized ammonium to nitrite. The low DO set-point combined with intermittent feeding was sufficient...

Linkages among climate change, crop yields and Mexico–US cross-border migration

Science.gov (United States)

Feng, Shuaizhang; Krueger, Alan B.; Oppenheimer, Michael

2010-01-01

Climate change is expected to cause mass human migration, including immigration across international borders. This study quantitatively examines the linkages among variations in climate, agricultural yields, and people's migration responses by using an instrumental variables approach. Our method allows us to identify the relationship between crop yields and migration without explicitly controlling for all other confounding factors. Using state-level data from Mexico, we find a significant effect of climate-driven changes in crop yields on the rate of emigration to the United States. The estimated semielasticity of emigration with respect to crop yields is approximately −0.2, i.e., a 10% reduction in crop yields would lead an additional 2% of the population to emigrate. We then use the estimated semielasticity to explore the potential magnitude of future emigration. Depending on the warming scenarios used and adaptation levels assumed, with other factors held constant, by approximately the year 2080, climate change is estimated to induce 1.4 to 6.7 million adult Mexicans (or 2% to 10% of the current population aged 15–65 y) to emigrate as a result of declines in agricultural productivity alone. Although the results cannot be mechanically extrapolated to other areas and time periods, our findings are significant from a global perspective given that many regions, especially developing countries, are expected to experience significant declines in agricultural yields as a result of projected warming. PMID:20660749

Peak capacity, peak-capacity production rate, and boiling point resolution for temperature-programmed GC with very high programming rates

Science.gov (United States)

Grall; Leonard; Sacks

2000-02-01

Recent advances in column heating technology have made possible very fast linear temperature programming for high-speed gas chromatography. A fused-silica capillary column is contained in a tubular metal jacket, which is resistively heated by a precision power supply. With very rapid column heating, the rate of peak-capacity production is significantly enhanced, but the total peak capacity and the boiling-point resolution (minimum boiling-point difference required for the separation of two nonpolar compounds on a nonpolar column) are reduced relative to more conventional heating rates used with convection-oven instruments. As temperature-programming rates increase, elution temperatures also increase with the result that retention may become insignificant prior to elution. This results in inefficient utilization of the down-stream end of the column and causes a loss in the rate of peak-capacity production. The rate of peak-capacity production is increased by the use of shorter columns and higher carrier gas velocities. With high programming rates (100-600 degrees C/min), column lengths of 6-12 m and average linear carrier gas velocities in the 100-150 cm/s range are satisfactory. In this study, the rate of peak-capacity production, the total peak capacity, and the boiling point resolution are determined for C10-C28 n-alkanes using 6-18 m long columns, 50-200 cm/s average carrier gas velocities, and 60-600 degrees C/min programming rates. It was found that with a 6-meter-long, 0.25-mm i.d. column programmed at a rate of 600 degrees C/min, a maximum peak-capacity production rate of 6.1 peaks/s was obtained. A total peak capacity of about 75 peaks was produced in a 37-s long separation spanning a boiling-point range from n-C10 (174 degrees C) to n-C28 (432 degrees C).

Dungloe Community Hospital, Gweedore Road, Dungloe, Donegal.

LENUS (Irish Health Repository)

Clarke, Nicholas

2017-09-25

The Global Code of Practice on the International Recruitment of Health Personnel focuses particularly on migration of doctors from low- and middle-income countries. Less is understood about migration from high-income countries. Recession has impacted several European countries in recent years, and in some cases emigration has reached unprecedented levels. This study measures and explores the predictors of trainee doctor emigration from Ireland.

Deposition Rates of High Power Impulse Magnetron Sputtering: Physics and Economics

Energy Technology Data Exchange (ETDEWEB)

Anders, Andre

2009-11-22

Deposition by high power impulse magnetron sputtering (HIPIMS) is considered by some as the new paradigm of advanced sputtering technology, yet this is met with skepticism by others for the reported lower deposition rates, if compared to rates of more conventional sputtering of equal average power. In this contribution, the underlying physical reasons for the rate changes are discussed, including (i) ion return to the target and self-sputtering, (ii) the less-than-linear increase of the sputtering yield with increasing ion energy, (iii) yield changes due to the shift of species responsible for sputtering, (iv) changes to due to greater film density, limited sticking, and self-sputtering on the substrate, (v) noticeable power losses in the switch module, (vi) changes of the magnetic balance and particle confinement of the magnetron due to self-fields at high current, and (vii) superposition of sputtering and sublimation/evaporation for selected materials. The situation is even more complicated for reactive systems where the target surface chemistry is a function of the reactive gas partial pressure and discharge conditions. While most of these factors imply a reduction of the normalized deposition rate, increased rates have been reported for certain conditions using hot targets and less poisoned targets. Finally, some points of economics and HIPIMS benefits considered.

Deposition rates of high power impulse magnetron sputtering: Physics and economics

International Nuclear Information System (INIS)

Anders, Andre

2010-01-01

Deposition by high power impulse magnetron sputtering (HIPIMS) is considered by some as the new paradigm of advanced sputtering technology, yet this is met with skepticism by others for the reported lower deposition rates, if compared to rates of more conventional sputtering of equal average power. In this contribution, the underlying physical reasons for the rate changes are discussed, including (i) ion return to the target and self-sputtering, (ii) the less-than-linear increase in the sputtering yield with increasing ion energy, (iii) yield changes due to the shift of species responsible for sputtering, (iv) changes due to greater film density, limited sticking, and self-sputtering on the substrate, (v) noticeable power losses in the switch module, (vi) changes in the magnetic balance and particle confinement of the magnetron due to self-fields at high current, and (vii) superposition of sputtering and sublimation/evaporation for selected materials. The situation is even more complicated for reactive systems where the target surface chemistry is a function of the reactive gas partial pressure and discharge conditions. While most of these factors imply a reduction in the normalized deposition rate, increased rates have been reported for certain conditions using hot targets and less poisoned targets. Finally, some points of economics and HIPIMS benefits are considered.

Depopulation of Vis Island, Croatia

Directory of Open Access Journals (Sweden)

Ivo Nejašmić

2006-01-01

Full Text Available The paper discusses population dynamics of Vis Island along with geographic, demographic and social features related to this process. Data from demographic statistics and research results show that Vis Island has been affected by strong populational regression. This process originated at the beginning of the 20th century, and intensified after the Second World War. Depopulation was generated by retardation in socio-economic development, but it was directly caused by centennial emigration. At the beginning of 1960s, natural decrease occurred as another important cause of depopulation. It was the result of postponed effect of emigration, demographic losses in world wars and birth rate transition (changes in number of children per family. Long-term unfavorable demographic processes (emigration, depopulation, demographic aging, reduced birth rates have led to weakening of (bioreproduction and vital potential. The above-mentioned fact has also influencedthe age structure of the population. Population of Vis Island has aged and belongs to a particular demographic type named very old population. However, depopulation, that used to be the result of social phenomena, has become an important factor of social and spatial processes.

Polyaniline-based memristive microdevice with high switching rate and endurance

Science.gov (United States)

Lapkin, D. A.; Emelyanov, A. V.; Demin, V. A.; Erokhin, V. V.; Feigin, L. A.; Kashkarov, P. K.; Kovalchuk, M. V.

2018-01-01

Polyaniline (PANI) based memristive devices have emerged as promising candidates for hardware implementation of artificial synapses (the key components of neuromorphic systems) due to their high flexibility, low cost, solution processability, three-dimensional stacking capability, and biocompatibility. Here, we report on a way of the significant improvement of the switching rate and endurance of PANI-based memristive devices. The reduction of the PANI active channel dimension leads to the increase in the resistive switching rate by hundreds of times in comparison with the conventional one. The miniaturized memristive device was shown to be stable within at least 104 cyclic switching events between high- and low-conductive states with a retention time of at least 103 s. The obtained results make PANI-based memristive devices potentially widely applicable in neuromorphic systems.

Effect of high heating rate on thermal decomposition behaviour of ...

Indian Academy of Sciences (India)

the thermal decomposition behaviour of the aforementioned powder at high heating rates was taken into considera- ... does not change the process of releasing hydrogen from titanium hydride ... from titanium hydride in a sequence of steps.

Scaling of black silicon processing time by high repetition rate femtosecond lasers

Directory of Open Access Journals (Sweden)

Nava Giorgio

2013-11-01

Full Text Available Surface texturing of silicon substrates is performed by femtosecond laser irradiation at high repetition rates. Various fabrication parameters are optimized in order to achieve very high absorptance in the visible region from the micro-structured silicon wafer as compared to the unstructured one. A 70-fold reduction of the processing time is demonstrated by increasing the laser repetition rate from 1 kHz to 200 kHz. Further scaling up to 1 MHz can be foreseen.

Effect of high heating rate on thermal decomposition behaviour of ...

Indian Academy of Sciences (India)

Effect of high heating rate on thermal decomposition behaviour of titanium hydride ... hydride powder, while switching it from internal diffusion to chemical reaction. ... TiH phase and oxides form on the powder surface, controlling the process.

High speed and adaptable error correction for megabit/s rate quantum key distribution.

Science.gov (United States)

Dixon, A R; Sato, H

2014-12-02

Quantum Key Distribution is moving from its theoretical foundation of unconditional security to rapidly approaching real world installations. A significant part of this move is the orders of magnitude increases in the rate at which secure key bits are distributed. However, these advances have mostly been confined to the physical hardware stage of QKD, with software post-processing often being unable to support the high raw bit rates. In a complete implementation this leads to a bottleneck limiting the final secure key rate of the system unnecessarily. Here we report details of equally high rate error correction which is further adaptable to maximise the secure key rate under a range of different operating conditions. The error correction is implemented both in CPU and GPU using a bi-directional LDPC approach and can provide 90-94% of the ideal secure key rate over all fibre distances from 0-80 km.

Accuracy assessment of high-rate GPS measurements for seismology

Science.gov (United States)

Elosegui, P.; Davis, J. L.; Ekström, G.

2007-12-01

Analysis of GPS measurements with a controlled laboratory system, built to simulate the ground motions caused by tectonic earthquakes and other transient geophysical signals such as glacial earthquakes, enables us to assess the technique of high-rate GPS. The root-mean-square (rms) position error of this system when undergoing realistic simulated seismic motions is 0.05~mm, with maximum position errors of 0.1~mm, thus providing "ground truth" GPS displacements. We have acquired an extensive set of high-rate GPS measurements while inducing seismic motions on a GPS antenna mounted on this system with a temporal spectrum similar to real seismic events. We found that, for a particular 15-min-long test event, the rms error of the 1-Hz GPS position estimates was 2.5~mm, with maximum position errors of 10~mm, and the error spectrum of the GPS estimates was approximately flicker noise. These results may however represent a best-case scenario since they were obtained over a short (~10~m) baseline, thereby greatly mitigating baseline-dependent errors, and when the number and distribution of satellites on the sky was good. For example, we have determined that the rms error can increase by a factor of 2--3 as the GPS constellation changes throughout the day, with an average value of 3.5~mm for eight identical, hourly-spaced, consecutive test events. The rms error also increases with increasing baseline, as one would expect, with an average rms error for a ~1400~km baseline of 9~mm. We will present an assessment of the accuracy of high-rate GPS based on these measurements, discuss the implications of this study for seismology, and describe new applications in glaciology.

Development of a high-count-rate neutron detector with position sensitivity and high efficiency

International Nuclear Information System (INIS)

Nelson, R.; Sandoval, J.

1996-01-01

While the neutron scattering community is bombarded with hints of new technologies that may deliver detectors with high-count-rate capability, high efficiency, gamma-ray insensitivity, and high resolution across large areas, only the time-tested, gas-filled 3 He and scintillation detectors are in widespread use. Future spallation sources with higher fluxes simply must exploit some of the advanced detector schemes that are as yet unproved as production systems. Technologies indicating promise as neutron detectors include pixel arrays of amorphous silicon, silicon microstrips, microstrips with gas, and new scintillation materials. This project sought to study the competing neutron detector technologies and determine which or what combination will lead to a production detector system well suited for use at a high-intensity neutron scattering source

Palaeohistological Evidence for Ancestral High Metabolic Rate in Archosaurs.

Science.gov (United States)

Legendre, Lucas J; Guénard, Guillaume; Botha-Brink, Jennifer; Cubo, Jorge

2016-11-01

Metabolic heat production in archosaurs has played an important role in their evolutionary radiation during the Mesozoic, and their ancestral metabolic condition has long been a matter of debate in systematics and palaeontology. The study of fossil bone histology provides crucial information on bone growth rate, which has been used to indirectly investigate the evolution of thermometabolism in archosaurs. However, no quantitative estimation of metabolic rate has ever been performed on fossils using bone histological features. Moreover, to date, no inference model has included phylogenetic information in the form of predictive variables. Here we performed statistical predictive modeling using the new method of phylogenetic eigenvector maps on a set of bone histological features for a sample of extant and extinct vertebrates, to estimate metabolic rates of fossil archosauromorphs. This modeling procedure serves as a case study for eigenvector-based predictive modeling in a phylogenetic context, as well as an investigation of the poorly known evolutionary patterns of metabolic rate in archosaurs. Our results show that Mesozoic theropod dinosaurs exhibit metabolic rates very close to those found in modern birds, that archosaurs share a higher ancestral metabolic rate than that of extant ectotherms, and that this derived high metabolic rate was acquired at a much more inclusive level of the phylogenetic tree, among non-archosaurian archosauromorphs. These results also highlight the difficulties of assigning a given heat production strategy (i.e., endothermy, ectothermy) to an estimated metabolic rate value, and confirm findings of previous studies that the definition of the endotherm/ectotherm dichotomy may be ambiguous. © The Author(s) 2016. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Precise muon drift tube detectors for high background rate conditions

CERN Document Server

Engl, Albert; Dünnweber, Wolfgang

The muon spectrometer of the ATLAS-experiment at the Large H adron Collider consists of drift tube chambers, which provide the precise m easurement of trajec- tories of traversing muons. In order to determine the moment um of the muons with high precision, the measurement of the position of the m uon in a single tube has to be more accurate than σ ≤ 100 m. The large cross section of proton-proton-collisions and th e high luminosity of the accelerator cause relevant background of neutrons and γ s in the muon spectrome- ter. During the next decade a luminosity upgrade [1] to 5 10 34 cm − 2 s − 1 is planned, which will increase the background counting rates consider ably. In this context this work deals with the further development of the existing drift chamber tech- nology to provide the required accuracy of the position meas urement under high background conditions. Two approaches of improving the dri ft tube chambers are described: • In regions of moderate background rates a faster and more lin ear ...

Frequency-locked pulse sequencer for high-frame-rate monochromatic tissue motion imaging.

Science.gov (United States)

Azar, Reza Zahiri; Baghani, Ali; Salcudean, Septimiu E; Rohling, Robert

2011-04-01

To overcome the inherent low frame rate of conventional ultrasound, we have previously presented a system that can be implemented on conventional ultrasound scanners for high-frame-rate imaging of monochromatic tissue motion. The system employs a sector subdivision technique in the sequencer to increase the acquisition rate. To eliminate the delays introduced during data acquisition, a motion phase correction algorithm has also been introduced to create in-phase displacement images. Previous experimental results from tissue- mimicking phantoms showed that the system can achieve effective frame rates of up to a few kilohertz on conventional ultrasound systems. In this short communication, we present a new pulse sequencing strategy that facilitates high-frame-rate imaging of monochromatic motion such that the acquired echo signals are inherently in-phase. The sequencer uses the knowledge of the excitation frequency to synchronize the acquisition of the entire imaging plane to that of an external exciter. This sequencing approach eliminates any need for synchronization or phase correction and has applications in tissue elastography, which we demonstrate with tissue-mimicking phantoms. © 2011 IEEE

Development of bonded semiconductor device for high counting rate high efficiency photon detectors

International Nuclear Information System (INIS)

Kanno, Ikuo

2008-01-01

We are trying to decrease dose exposure in medical diagnosis by way of measuring the energy of X-rays. For this purpose, radiation detectors for X-ray energy measurement with high counting rate should be developed. Direct bonding of Si wafers was carried out to make a radiation detector, which had separated X-ray absorber and detector. The resistivity of bonding interface was estimated with the results of four-probe measurements and model calculations. Direct bonding of high resistivity p and n-Si wafers was also performed. The resistance of the pn bonded diode was 0.7 MΩ. The resistance should be increased in the future. (author)

New Approach to reduce High School Dropout Rates

Directory of Open Access Journals (Sweden)

Mauricio Cristhian Portillo-Torres

2015-05-01

Full Text Available From 2006 to 2014, the Ministry of Public Education of Costa Rica implemented four strategic actions to reduce high school dropout rates. The main purpose of these actions was to promote student participation and student identification with their school. Studies prepared by the Ministry of Education and the Comptroller of the Republic were revised to assess the impact of these actions. The result of these actions does not show an actual decrease in the number of students who leave high school. Therefore, a more holistic view is necessary to ensure the students’ stay. This review suggests using use the concept of student engagement and applying a three tier system-wide dropout preventive actions: universal, targeted and intensive.

Sphaleron rate at high temperature in 1+1 dimensions

International Nuclear Information System (INIS)

Smit, Jan; Tang, W.H.

1999-01-01

We resolve the controversy in the high temperature behavior of the sphaleron rate in the abelian Higgs model in 1+1 dimensions. The T 2 behavior at intermediate lattice spacings is found to change into T ((2)/(3)) behavior in the continuum limit. The results are supported by analytic arguments that the classical approximation is good for this model

High-rate synthesis of phosphine-stabilized undecagold nanoclusters using a multilayered micromixer

International Nuclear Information System (INIS)

Jin, Hyung Dae; Chang, Chih-Hung; Garrison, Anna; Tseng, T; Paul, Brian K

2010-01-01

Growth in the potential applications of nanomaterials has led to a focus on the development of new manufacturing approaches for these materials. In particular, an increased demand due to the unique properties of nanomaterials requires a substantial yield of high-performance materials and a simultaneous reduction in the environmental impact of these processes. In this paper, a high-rate production of phosphine-stabilized undecagold nanoclusters was achieved using a layer-up strategy which involves the use of microlamination architectures; the patterning and bonding of thin layers of material (laminae) to create a multilayered micromixer in the range of 25-250 μm thick was used to step up the production of phosphine-stabilized undecagold nanoclusters. The continuous production of highly monodispersed phosphine-stabilized undecagold nanoclusters at a rate of about 11.8 (mg s -1 ) was achieved using a microreactor with a size of 1.687 cm 3 . This result is about 500 times over conventional batch syntheses based on the production rate per reactor volume.

Grain growth behavior and high-temperature high-strain-rate tensile ductility of iridium alloy DOP-26

International Nuclear Information System (INIS)

McKamey, C.G.; Gubbi, A.N.; Lin, Y.; Cohron, J.W.; Lee, E.H.; George, E.P.

1998-04-01

This report summarizes results of studies conducted to date under the Iridium Alloy Characterization and Development subtask of the Radioisotope Power System Materials Production and Technology Program to characterize the properties of the new-process iridium-based DOP-26 alloy used for the Cassini space mission. This alloy was developed at Oak Ridge National Laboratory (ORNL) in the early 1980's and is currently used by NASA for cladding and post-impact containment of the radioactive fuel in radioisotope thermoelectric generator (RTG) heat sources which provide electric power for interplanetary spacecraft. Included within this report are data generated on grain growth in vacuum or low-pressure oxygen environments; a comparison of grain growth in vacuum of the clad vent set cup material with sheet material; effect of grain size, test temperature, and oxygen exposure on high-temperature high-strain-rate tensile ductility; and grain growth in vacuum and high-temperature high-strain-rate tensile ductility of welded DOP-26. The data for the new-process material is compared to available old-process data

Macroeconomic effects of high interest rate policy: Mexico’s experience

Directory of Open Access Journals (Sweden)

Julio Lopez Gallardo

2015-09-01

Full Text Available We study the effects of the high interest rate policy implemented in Mexico under the inflation targeting (IT scheme on the price level and on GDP and its components. We specify a macroeconomic model inspired by the theory of the effective demand, and on this basis we demonstrate, through comparative statics, the complex set of relationships between the variables involved, and the chain of reactions that a shock to the interest rate is likely to provoke. Our main conclusions show that an interest rate rise may be instrumental to control inflation. However, this rise contributes to appreciate the exchange rate, which is the main channel through which inflation is tamed. Currency appreciation raises the share of wages in GDP even as it reduces the debt service of firms indebted in dollars. It follows that the interest rate rise may have, under certain conditions, an indirect positive impact on output. Thus, our results diverge from those entailed by the theory that is at the basis of the inflation-targeting strategy, and even from some contemporary non-conventional approaches.

High and low dose-rate brachytherapy for cervical carcinoma

International Nuclear Information System (INIS)

Orton, C.G.

1998-01-01

For the brachytherapy component of the r[iation treatment of cervical carcinoma, high dose rate (HDR) is slowly replacing conventional low dose rate (LDR) due primarily to r[iation safety and other physical benefits attributed to the HDR modality. Many r[iation oncologists are reluctant to make this change because of perceived r[iobiological dis[vantages of HDR. However, in clinical practice HDR appears to be as effective as LDR but with a lower risk of late complications, as demonstrated by one randomized clinical trial and two comprehensive literature and practice surveys. The reason for this appears to be that the r[iobiological dis[vantages of HDR are outweighed by the physical [vantages. (orig.)

Treatment of the prostate cancer with high dose rate brachytherapy

International Nuclear Information System (INIS)

Martinez, Alvaro; Torres Silva, Felipe

2002-01-01

The prostate cancer treatment in early stages is controversial. The high dose rate brachytherapy has been used like monotherapy or boost with external beam radiotherapy in advanced disease. This paper describes the technique and the advantages over other modalities

High Data Rate Architecture (HiDRA)

Science.gov (United States)

Hylton, Alan; Raible, Daniel

2016-01-01

high-rate laser terminals. These must interface with the existing, aging data infrastructure. The High Data Rate Architecture (HiDRA) project is designed to provide networked store, carry, and forward capability to optimize data flow through both the existing radio frequency (RF) and new laser communications terminal. The networking capability is realized through the Delay Tolerant Networking (DTN) protocol, and is used for scheduling data movement as well as optimizing the performance of existing RF channels. HiDRA is realized as a distributed FPGA memory and interface controller that is itself controlled by a local computer running DTN software. Thus HiDRA is applicable to other arenas seeking to employ next-generation communications technologies, e.g. deep space. In this paper, we describe HiDRA and its far-reaching research implications.

The IMF’s High Interest Rate Policy and Its Effects on the Stabilization of the Korean Won

Directory of Open Access Journals (Sweden)

Tae-Joon Kim

2000-03-01

Full Text Available There has been a lively debate whether high interest rates were effective in stabilizing the exchange rate in the wake of the Asian currency crisis. Many economists insist that high interest rates not only failed to stabilize the Korean won, but also exacerbated the crisis itself. This paper tries to shed light on this problem by providing empirical evidence from the high interest rate period. (1997. 12. 3 ? 1998. 4. 8 If possible channels whereby interest rates may affect exchange rates are examined, the high interest rate policy scores well. It accommodated net capital inflow by satisfying the interest rate parity condition. Also it helped rebuild credibility of the policy stance. While the negative impact of high interest rates on the private sector cannot be denied, the role of credit crunch needs to be recognized together. Next, the dynamic interaction between interest rates and exchange rates is analyzed using a vector error correction model composed of interest rate differential, spot and forward exchange rates, and country risk premium. The estimation result shows that a 10% point rise in domestic interest rate appreciates the Korean won by 25%. In addition, the country risk premium considerably falls down. In sum, it may be concluded that the high interest rate policy was effective in achieving its goal of stabilizing exchange rates.

Audits in high dose rate brachytherapy in Brazil

International Nuclear Information System (INIS)

Marechal, M.H.; Rosa, L.A.; Velasco, A.; Paiva, E. de; Goncalves, M.; Castelo, L.C.

2002-01-01

The lack of well established dosimetry protocols for HDR sources is a point of great concern regarding the uniformity of procedures within a particular country. The main objective of this paper is to report the results of an implementation of the audit program in dosimetry of high dose rate brachytherapy sources used by the radiation therapy centers in Brazil. In Brazil, among 169 radiotherapy centers, 35 have HDR brachytherapy systems. This program started in August 2001 and until now eight radiotherapy services were audited. The audit program consists of the visit in loco to each center and the evaluation of the intensity of the source with a well type chamber specially design for HDR 192 Ir sources. The measurements was carried out with a HDR1000PLUS Brachytherapy Well Type Chamber and a MAX 4000 Electrometer, both manufactured by Standard Imaging Inc. The chamber was calibrated in air kerma strength by the Accredited Dosimetry Calibration Laboratory, Department of Medical Physics, University of Wisconsin in the USA. The same chamber was calibrated in Brazil using a 192 lr high dose rate source whose intensity was determined by 60 Co gamma rays and 250 kV x rays interpolation methodology. The Nk of 60 Co and 250 kV x rays were provided by the Brazilian National Standard Laboratory for Ionizing Radiation (LMNRI)

Consideration of wear rates at high velocity

Science.gov (United States)

Hale, Chad S.

The development of the research presented here is one in which high velocity relative sliding motion between two bodies in contact has been considered. Overall, the wear environment is truly three-dimensional. The attempt to characterize three-dimensional wear was not economically feasible because it must be analyzed at the micro-mechanical level to get results. Thus, an engineering approximation was carried out. This approximation was based on a metallographic study identifying the need to include viscoplasticity constitutive material models, coefficient of friction, relationships between the normal load and velocity, and the need to understand wave propagation. A sled test run at the Holloman High Speed Test Track (HHSTT) was considered for the determination of high velocity wear rates. In order to adequately characterize high velocity wear, it was necessary to formulate a numerical model that contained all of the physical events present. The experimental results of a VascoMax 300 maraging steel slipper sliding on an AISI 1080 steel rail during a January 2008 sled test mission were analyzed. During this rocket sled test, the slipper traveled 5,816 meters in 8.14 seconds and reached a maximum velocity of 1,530 m/s. This type of environment was never considered previously in terms of wear evaluation. Each of the features of the metallography were obtained through micro-mechanical experimental techniques. The byproduct of this analysis is that it is now possible to formulate a model that contains viscoplasticity, asperity collisions, temperature and frictional features. Based on the observations of the metallographic analysis, these necessary features have been included in the numerical model, which makes use of a time-dynamic program which follows the movement of a slipper during its experimental test run. The resulting velocity and pressure functions of time have been implemented in the explicit finite element code, ABAQUS. Two-dimensional, plane strain models

Identity work and cosmopolitanism among young Danish high-skilled emigrants

DEFF Research Database (Denmark)

Yndigegn, Carsten

The paper outlines a theoretical framework for the analysis of the relation between transnational mobility and spatial identity. In four sections the theoretical framework is outlined. The concepts of mobility in classic modernity and late modernity are outlined and discussed. Then, the concepts...... the national and transnational spatial identities are briefly sketched and discussed against the new postmodern cosmopolitanism. In a fifth section two empirical cases are presented, and in the last section the cases are discussed against the theoretical framework. The section ends by stating the limitation...... of the conceptualization and analysis so far, and proposing the need for further research....

Federal High School Graduation Rate Policies and the Impact on Georgia

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Nebraska

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Hawaii

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Mississippi

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Illinois

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on California

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Colorado

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Indiana

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Arizona

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Louisiana

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Michigan

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Connecticut

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Delaware

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Florida

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Arkansas

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Maine

Science.gov (United States)

Alliance for Excellent Education, 2009

2009-01-01

In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

Federal High School Graduation Rate Policies and the Impact on Alaska

Science.gov (United States)