Patterns and Correlates of Research Productivity in Population Scientists.

ERIC Educational Resources Information Center

Richards, James M., Jr.

Although a concern with population issues has gone out of fashion, the problems underlying that concern have not disappeared. Solving these problems would be facilitated by increased knowledge produced by scientists working directly on population issues. A study was conducted to explore patterns and correlates of research productivity of members…

Population Growth and Global Security: Toward an American Strategic Commitment.

ERIC Educational Resources Information Center

Mumford, Steven

1981-01-01

Addresses the world population problem by highlighting three crucial areas: the relationship between population growth control and national security issues, the role of American leadership in resolving the problem, and the barriers to effective action. One barrier discussed in detail is the Roman Catholic Church's stand on abortion and…

Responses to Simon and Other Population Revisionists.

ERIC Educational Resources Information Center

Campbell, Martha

1993-01-01

Population revisionists are cited as people who do not believe that global population growth is a problem. This paper presents a small sampling of responses to revisionist books and articles, primarily focused on perceived technical problems in the revisionist position as identified by demography, economics, and hard science specialists. Includes…

Soviet Marxism and population policy.

PubMed

Vonfrank, A

1984-01-01

American demographers have maintained that Marxism, notably Soviet Marxism, is consistently pronatalist. The Soviet view is said to be that population growth is not a problem and that birth control policies in either developed or developing societies are to be rejected; the "correct" (i.e., socialist) socioeconomic structure is the true solution to alleged population problems. Such representations of Soviet thought greatly oversimplify the Soviet position as well as fail to discern the changes in Soviet thought that have been occurring. Since the 1960s Soviet writers have increasingly acknowledged that population growth is, to a considerable degree, independent of the economic base of society and that conscious population policies may be needed to either increase or decrease the rate of population growth. Even socialist societies can have population problems. And where population growth is too rapid, as in the developing countries, policies to slow such growth are needed because of the threat to economic development. However, the Soviets continue to stress that birth control policies must go hand-in-hand with social and economic development policies if they are to be effective.

Some thoughts on ICPD+5.

PubMed

AbouZahr, C

1999-01-01

This article concerns the International Conference on Population and Development (ICPD) held in Cairo in 1994. The 1960s were the years when the UNFPA was conceived and established with a mandate to raise awareness about the population problem and to assist developing countries in addressing these problems. At that time, the topics of discussion were focused on population bombs, demographic entrapment, scarcity of food, water, and renewable resources. The concern on population dates back much further of course to Malthus and his contemporaries and their analysis of the relationship between population growth and food availability. Many population programs and policies were implemented to address the population problems in developing countries such as the rapid increase in availability of technologies for reducing fertility. In contrast, the present Cairo agenda paid more attention to women's empowerment, autonomy and the improvement of their political, social, economic and health status for the attainment of sustainable development. The trend towards the feminist agenda explains the continuing tensions, so vociferously expressed during the ICPD+5 process, between conservatives and progressive groups.

The real problem.

PubMed

Godfrey, M

1997-01-01

I really was dismayed to see the basic cause of all our planet's problems buried in the September/October 96 issue: "...religious zealots might wreck the family planning needs of a billion people...." Let's face hard facts: all these problems would go away if the planet's population were small enough. What we really need to establish is what the population of the earth should be, and then set out to achieve that population as soon as possible. All of our efforts to reduce automobile pollution, the amount of reactor waste, the number of species being obliterated, etc., are just postponing the inevitable. What we need to look at, and keep track of, are those factors that encourage expanding population and discourage population control. For example, most businesses like to see the population expand so they can have a growing customer base. I truly appreciate your efforts. But if we are going to get anywhere we have to clearly identify the real problem. And then we have to break it down into manageable pieces and go to work on them. Otherwise we are going to keep looking at the graphs and wringing our hands as this accumulation of problems builds until it sweeps over us like a giant tsunami. full text

The population problem: conceptions and misconceptions.

PubMed

Berelson, B

1971-01-01

Only 1 in about 110 sex acts results in a conception and 1 in 270 in a live birth. Of all conceptions, 40% result in live births, 5% in stillbirths, and 55% never develop. 1/3 of all known conceptions ends in abortion, spontaneous or induced. It appears that the population problem depends on a small fraction of the potential. Misconceptions of the problem are corrected, and it is emphasized that while no social problem facing the U.S. would be easier with a larger population, demographic factors do not cause all of the other problems. Increasing numbers are not as important as the rate of increase (2% annually worldwide). Today's population problem has been caused by a decreased death rate, not an increased birthrate. There are 2 kinds of countries in the world today: those with a high standard of living and low fertility and those with a low standard of living and high fertility. Most of the uninformed women of the world would not choose to have large numbers of children if they had a choice. Population density is not a problem in itself. Experts disagree, but it is improbable that large numbers of people will die of starvation in the next few decades. Environmental deterioration is more the result of modern economic and technological practices than of demographic factors. Efforts at fertility control are not aimed at minorities in this country and elsewhere. The poor are discriminated against in access to family planning services and abortion. Moslems of developing countries have higher fertility rates than Roman Catholics in developed countries. There would be many social costs if the U.S. were to achieve zero population growth in the near future. The population problem has implications for the future quality of life.

Bowel, Urinary, and Sexual Problems Among Long-Term Prostate Cancer Survivors: A Population-Based Study

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

Mols, Floortje; Comprehensive Cancer Centre South; Korfage, Ida J.

Purpose: To obtain insight into the long-term (5- to 10-year) effects of prostate cancer and treatment on bowel, urinary, and sexual function, we performed a population-based study. Prostate-specific function was compared with an age-matched normative population without prostate cancer. Methods and Materials: Through the population-based Eindhoven Cancer Registry, we selected all men diagnosed with prostate cancer between 1994 and 1998 in the southern Netherlands. In total, 964 patients, alive in November 2004, received questionnaire; 780 (81%) responded. Results: Urinary problems were most common after a prostatectomy; bowel problems were most common after radiotherapy. Compared with an age-matched normative population bothmore » urinary and bowel functioning and bother were significantly worse among survivors. Urinary incontinence was reported by 23-48% of survivors compared with 4% of the normative population. Bowel leakage occurred in 5-14% of patients compared with 2% of norms. Erection problems occurred in 40-74% of patients compared with 18% of norms. Conclusions: These results form an important contribution to the limited information available on prostate-specific problems in the growing group of long-term prostate cancer survivors. Bowel, urinary, and sexual problems occur more often among long-term survivors compared with a reference group and cannot be explained merely by age. Because these problems persist for many years, urologists should provide patients with adequate information before treatment. After treatment, there should be an appropriate focus on these problems.« less

[Problems of population and agricultural development in Rwanda].

PubMed

Sibomana, J M

1984-01-01

The primary goal of law 3/81 created by the National Office of Population (l'Office National de la Population--ONAPU) in 1981, is to establish a demographic policy consistent with national realities and designed to ease the problem of overpopulation. ONAPU supports family planning for all of Rwanda as an approach to the population situation. The family planning objective promotes conscientious and wanted procreation. It encourages couples to have children in accordance with a preestablished plan, which takes into account the size of the family and the calendar of procreation. Unmatched population growth with limited economic growth have been major concerns for ONAPU; hence, emphasis on maintaining a level of equilibrium between the 2 is a national priority. In the meantime, increased population growth has been causing agricultural problems. Small amounts of land available for cultivation and rudimentary agricultural technology necessitate a change in the financial organization of this sector. Simultaneously, there is an abundance of agricultural workers and a threat of famine due to population demands outstripping subsistence yields. If the population growth rate of Rwanda remains at 3.79%, the land will be insufficient. To avoid future problems, a financial revolution which involves both the agricultural and nonagricultural sectors must be planned. Economic, social, and cultural reorganization is critical, especially for family planning. The policy of spacing births will not be accepted without amelioration 1st family and community health.

The Why and How of Population Education

ERIC Educational Resources Information Center

Seffrin, John R.

1975-01-01

Discusses the importance of instructional programs concerning population education and describes population growth in the United States, the biological reasons for the overpopulation problem, and the role of the health educator in population education. (BD)

[Opinions of Chinese demographers on population development in China and in the world].

PubMed

Tomala, K

1983-01-01

The authors analyze problems connected with demograhic policy and the important stages of population development on the basis of recently published Chinese data. Ideological and political aspects of population policy in China are discussed; it is stated that the country's leadership considers a quick rise in population to be a regularity in the development of a socialist society. Thus, consideration is given to arising social problems: provision of food, dwelling places, rearing and education, and creation of new places of work. This article explains why China presently feels that the solutioon to the population problem is of worldwide importance and could play a role in the country's process of modernization. In this connection, some new theories of Chinese population development are discussed and analyzed. Chinese scholars state that as China has more than 22% of the world population, this makes them necessarily responsible for a reduction in world population. A large section of this paper id devoted to the drastic population policy begun in 1978 and represented by the slogan of "families with 1 child". Optimum for popluation as well as discussion of food resources, ecologic equilibrium, water resources, and arable land are also mentioned. This is the basis for showing that China's population should not be more than 700 million. Difficulties concerning this population policy are discussed, especiallty in the rural areas. The implementation of principles of population policy are imperative for any country, and particularly for China. The question arises as to whether such a drastic population policy is the only manner for China to accomplish their goals. Results of the 3rd population census, also presented in this paper, have become the basis for a comprehensive research work which will serve to establish indicators for China's further development. (author's modified)

Monitoring Population Evolution in the Pearl River Delta from 2000 TO 2010

NASA Astrophysics Data System (ADS)

Yu, S.; Liu, F.; Zhang, Z.

2018-04-01

On behalf of more populous and developed regions in China, urban agglomerations have become important carries loading active economic activities and generous social benefits, and experienced sharper population increase, which results in great threat on local eco-environment construction. Therefore, exact and detailed population monitoring and analyzing, especially on the long sequence and multi frequency, is of great significance. The nighttime light time-series (NLT) products has been proven to be one of the most useful remotely sensed imagery to acquire persons at 1 km × 1 km scales. However, the existed problems, such as light saturation and blooming, greatly limit the accuracy of estimated results. Furthermore, it's difficult to spatialize population at km2 level due to the lack of basic data in non-census years. In order to solve all problems mentioned above, the populous Pearl River Delta was selected as the study area. A new residential extent extraction index (REEI) was proposed to solve light saturation and blooming problems. Population spatialization methods in census and non-census years were applied to acquire detailed population distribution from 2000 to 2010. Results showed the feasibility of the proposed methods in this work. During the decade, population was denser in the central PRD and sparser in the eastern, western and northern PRD. The speed of population increase was various in nine cities, but faster in 2000-2005 than 2005-2010.

A Role for M-Matrices in Modelling Population Growth

ERIC Educational Resources Information Center

James, Glyn; Rumchev, Ventsi

2006-01-01

Adopting a discrete-time cohort-type model to represent the dynamics of a population, the problem of achieving a desired total size of the population under a balanced growth (contraction) and the problem of maintaining the desired size, once achieved, are studied. Properties of positive-time systems and M-matrices are used to develop the results,…

Self-reported occupational exposure to chemical and physical factors and risk of skin problems: a 3-year follow-up study of the general working population of Norway.

PubMed

Alfonso, Jose Hernan; Thyssen, Jacob P; Tynes, Tore; Mehlum, Ingrid Sivesind; Johannessen, Håkon A

2015-11-01

Prospective studies on occupational dermatoses in the general working population are sparse. This study investigated prospectively the impact of self-reported occupational exposure to chemicals and physical factors on the risk of skin problems. The cohort comprised respondents drawn randomly from the general population in Norway, who were registered employed in 2006 and 2009 (n = 6,745). Indoor dry air (odds ratio (OR) 1.3; 95% confidence interval (95% CI) 1.1-1.6) was a significant baseline predictor of skin problems at follow-up, whereas exposure to cleaning products (OR 1.7; 95% CI 1.2-2.5), water (OR 1.4; 95% CI 1.1-1.9) and indoor dry air (OR 1.6; 95% CI 1.1-2.1) at both measurement time-points was significantly associated with skin problems. The population risk attributable to these factors was 16%. This study quantified the contribution of occupational exposure factors to skin problems in the general working population of Norway.

Population, Education, and Children's Futures. Fastback 150.

ERIC Educational Resources Information Center

Bjork, Robert M.; Fraser, Stewart E.

This monograph discusses world population problems, examines the underlying concepts and issues in population education, and looks at the future. The monograph begins by describing an attempt at population education in a village of India. Eight guiding concepts that are considered to be essential for population educators are then discussed. These…

Current status and future directions of the population control policies in Korea.

PubMed

Cho, N H; Seo, M H

1989-07-01

Recent changes in demographic and socioeconomic conditions in Korea are reviewed, as are population control policies so that future policy directions can be established. Major data sources include the 1988 National Fertility and Family Health Survey and the 1985 Population and Housing Census of NBOS, EPB. The Korean population increased from 25.0 million in 1960 to 42.4 million in 1989. Population growth rate declined from 3.0% per annum to l.0% at the same time. The total fertility rate went down from 6.0/women to 1.6, from 1960 to 1987. This was due to a family planning program and socioeconomic development. In the Sixth Five-Year Plan (1987-1991), the government changed the demographic goals to further reduce the population growth rate to 0.96% by 1991. The estimated 1987 population of 41.6 million should reach 43.2 million by 1991. Korea will face 3 major population problems: an increase of the elderly population, rapid urbanization and shortage of resources. Emigration programs have been carried out to relieve the pressure of population. For the last 29 years, rural to urban migration has existed. A national family planning program exists. 16.4 million acceptors have received contraception under this program. There are, however, a number of problems. Reduction in population growth will help the world food supply problem and the housing shortage. Energy use has grown. Population and environmental planning should work together. Goals should change from reduction of fertility to eliminating problems with contraceptive acceptance and use effectiveness. There should be a greater choice of methods of contraception. The government functions of the family planning program should be given over to private organizations. The family planning program should be integrated with public health programs. Acceptors should pay for their contraceptives. The family planning program should enlarge its realm of activities. The information, education, communication part of the program should be revised. Individual program activities should be evaluated. Appendix 1 presents new population projections for 1987-2020. Changes in composition of the population are given in table form in Appendix 2.

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

Krummel, J.R.; Markin, J.B.; O'Neill, R.V.

Regional analyses of the interaction between human populations and natural resources must integrate landscape scale environmental problems. An approach that considers human culture, environmental processes, and resource needs offers an appropriate methodology. With this methodology, we analyze problems of food availability in African cattle-keeping societies. The analysis interrelates cattle biomass, forage availability, milk and blood production, crop yields, gathering, food subsidies, population, and variable precipitation. While an excess of cattle leads to overgrazing, cattle also serve as valuable food storage mechanisms during low rainfall periods. Food subsidies support higher population levels but do not alter drought-induced population fluctuations. Variable precipitationmore » patterns require solutions that stabilize year-to-year food production and also address problems of overpopulation.« less

Aboriginal Gambling and Problem Gambling: A Review

ERIC Educational Resources Information Center

Breen, Helen; Gainsbury, Sally

2013-01-01

The prevention of gambling-related problems amongst Aboriginal communities has been neglected by most public health strategies which concentrate on mainstream populations. Research indicates that rates of problem gambling are higher for Aboriginal groups than the general population. Specific cultural, familial, and social patterns influence…

International Students: A Vulnerable Student Population

ERIC Educational Resources Information Center

Sherry, Mark; Thomas, Peter; Chui, Wing Hong

2010-01-01

This study examines the experiences of international students at The University of Toledo, where international students comprise approximately 10% of the student population. It highlights problems international students experience such as adapting to a new culture, English language problems, financial problems and lack of understanding from the…

Independent Correlates of Reported Gambling Problems amongst Indigenous Australians

ERIC Educational Resources Information Center

Stevens, Matthew; Young, Martin

2010-01-01

To identify independent correlates of reported gambling problems amongst the Indigenous population of Australia. A cross-sectional design was applied to a nationally representative sample of the Indigenous population. Estimates of reported gambling problems are presented by remoteness and jurisdiction. Multivariable logistic regression was used to…

Discontinuous Galerkin finite element method for solving population density functions of cortical pyramidal and thalamic neuronal populations.

PubMed

Huang, Chih-Hsu; Lin, Chou-Ching K; Ju, Ming-Shaung

2015-02-01

Compared with the Monte Carlo method, the population density method is efficient for modeling collective dynamics of neuronal populations in human brain. In this method, a population density function describes the probabilistic distribution of states of all neurons in the population and it is governed by a hyperbolic partial differential equation. In the past, the problem was mainly solved by using the finite difference method. In a previous study, a continuous Galerkin finite element method was found better than the finite difference method for solving the hyperbolic partial differential equation; however, the population density function often has discontinuity and both methods suffer from a numerical stability problem. The goal of this study is to improve the numerical stability of the solution using discontinuous Galerkin finite element method. To test the performance of the new approach, interaction of a population of cortical pyramidal neurons and a population of thalamic neurons was simulated. The numerical results showed good agreement between results of discontinuous Galerkin finite element and Monte Carlo methods. The convergence and accuracy of the solutions are excellent. The numerical stability problem could be resolved using the discontinuous Galerkin finite element method which has total-variation-diminishing property. The efficient approach will be employed to simulate the electroencephalogram or dynamics of thalamocortical network which involves three populations, namely, thalamic reticular neurons, thalamocortical neurons and cortical pyramidal neurons. Copyright © 2014 Elsevier Ltd. All rights reserved.

Population Issues. Resources in Technology.

ERIC Educational Resources Information Center

Technology Teacher, 1991

1991-01-01

Presents information about the problems caused by increasing population. Discusses the environmental impact and the ways that technology can be used to solve problems of overpopulation. Includes possible student outcomes and a student quiz. (JOW)

How-To-Do-It: Multiple Allelic Frequencies in Populations at Equilibrium: Algorithms and Applications.

ERIC Educational Resources Information Center

Nussbaum, Francis, Jr.

1988-01-01

Presents an algorithm for solving problems related to multiple allelic frequencies in populations at equilibrium. Considers sample problems and provides their solution using this tabular algorithm. (CW)

Introduction of a Population Balance Based Design Problem in a Particle Science and Technology Course for Chemical Engineers

ERIC Educational Resources Information Center

Ehrman, Sheryl H.; Castellanos, Patricia; Dwivedi, Vivek; Diemer, R. Bertrum

2007-01-01

A particle technology design problem incorporating population balance modeling was developed and assigned to senior and first-year graduate students in a Particle Science and Technology course. The problem focused on particle collection, with a pipeline agglomerator, Cyclone, and baghouse comprising the collection system. The problem was developed…

Hybridization of decomposition and local search for multiobjective optimization.

PubMed

Ke, Liangjun; Zhang, Qingfu; Battiti, Roberto

2014-10-01

Combining ideas from evolutionary algorithms, decomposition approaches, and Pareto local search, this paper suggests a simple yet efficient memetic algorithm for combinatorial multiobjective optimization problems: memetic algorithm based on decomposition (MOMAD). It decomposes a combinatorial multiobjective problem into a number of single objective optimization problems using an aggregation method. MOMAD evolves three populations: 1) population P(L) for recording the current solution to each subproblem; 2) population P(P) for storing starting solutions for Pareto local search; and 3) an external population P(E) for maintaining all the nondominated solutions found so far during the search. A problem-specific single objective heuristic can be applied to these subproblems to initialize the three populations. At each generation, a Pareto local search method is first applied to search a neighborhood of each solution in P(P) to update P(L) and P(E). Then a single objective local search is applied to each perturbed solution in P(L) for improving P(L) and P(E), and reinitializing P(P). The procedure is repeated until a stopping condition is met. MOMAD provides a generic hybrid multiobjective algorithmic framework in which problem specific knowledge, well developed single objective local search and heuristics and Pareto local search methods can be hybridized. It is a population based iterative method and thus an anytime algorithm. Extensive experiments have been conducted in this paper to study MOMAD and compare it with some other state-of-the-art algorithms on the multiobjective traveling salesman problem and the multiobjective knapsack problem. The experimental results show that our proposed algorithm outperforms or performs similarly to the best so far heuristics on these two problems.

Skipping Strategy (SS) for Initial Population of Job-Shop Scheduling Problem

NASA Astrophysics Data System (ADS)

Abdolrazzagh-Nezhad, M.; Nababan, E. B.; Sarim, H. M.

2018-03-01

Initial population in job-shop scheduling problem (JSSP) is an essential step to obtain near optimal solution. Techniques used to solve JSSP are computationally demanding. Skipping strategy (SS) is employed to acquire initial population after sequence of job on machine and sequence of operations (expressed in Plates-jobs and mPlates-jobs) are determined. The proposed technique is applied to benchmark datasets and the results are compared to that of other initialization techniques. It is shown that the initial population obtained from the SS approach could generate optimal solution.

Creating targeted initial populations for genetic product searches in heterogeneous markets

NASA Astrophysics Data System (ADS)

Foster, Garrett; Turner, Callaway; Ferguson, Scott; Donndelinger, Joseph

2014-12-01

Genetic searches often use randomly generated initial populations to maximize diversity and enable a thorough sampling of the design space. While many of these initial configurations perform poorly, the trade-off between population diversity and solution quality is typically acceptable for small-scale problems. Navigating complex design spaces, however, often requires computationally intelligent approaches that improve solution quality. This article draws on research advances in market-based product design and heuristic optimization to strategically construct 'targeted' initial populations. Targeted initial designs are created using respondent-level part-worths estimated from discrete choice models. These designs are then integrated into a traditional genetic search. Two case study problems of differing complexity are presented to illustrate the benefits of this approach. In both problems, targeted populations lead to computational savings and product configurations with improved market share of preferences. Future research efforts to tailor this approach and extend it towards multiple objectives are also discussed.

Prevalence and Risk Markers of Behavior Problems among Adults with Intellectual Disabilities: A Total Population Study in Orebro County, Sweden

ERIC Educational Resources Information Center

Lundqvist, Lars-Olov

2013-01-01

The aim of the present study was to investigate the prevalence of behavior problems among people with administratively defined intellectual disability (ID) and identify possible risk markers for behavior problems using the Behavior Problems Inventory (BPI). Sixty-two percent of the ID population (n = 915) had a behavior problem (self-injurious,…

The Migration Behavior of College Students in Siberia

ERIC Educational Resources Information Center

Gorbacheva, E. A.

2008-01-01

Given the conditions of the aging of the population of Russia there has been a steady decline in the size of the population, and starting in 2006 that includes a decline in the size of the working-age population. This is a very serious problem in regard to the social and economic development of the country, and the ways to solve the problem will…

Computer simulation of population dynamics inside the urban environment

NASA Astrophysics Data System (ADS)

Andreev, A. S.; Inovenkov, I. N.; Echkina, E. Yu.; Nefedov, V. V.; Ponomarenko, L. S.; Tikhomirov, V. V.

2017-12-01

In this paper using a mathematical model of the so-called “space-dynamic” approach we investigate the problem of development and temporal dynamics of different urban population groups. For simplicity we consider an interaction of only two population groups inside a single urban area with axial symmetry. This problem can be described qualitatively by a system of two non-stationary nonlinear differential equations of the diffusion type with boundary conditions of the third type. The results of numerical simulations show that with a suitable choice of the diffusion coefficients and interaction functions between different population groups we can receive different scenarios of population dynamics: from complete displacement of one population group by another (originally more “aggressive”) to the “peaceful” situation of co-existence of them together.

Dealing with China's future population decline: a proposal for replacing low birth rates with sustainable rates.

PubMed

Cao, Shixiong; Wang, Xiuqing

2009-09-01

Decreasing population levels due to declining birth rates are becoming a potentially serious social problem in developed and rapidly developing countries. China urgently needed to reduce birth rates so that its population would decline to a sustainable level, and the family planning policy designed to achieve this goal has largely succeeded. However, continuing to pursue this policy is leading to serious, unanticipated problems such as a shift in the country's population distribution towards the elderly and increasing difficulty supporting that elderly population. Social and political changes that promoted low birth rates and the lack of effective policies to encourage higher birth rates suggest that mitigating the consequences of the predicted population decline will depend on a revised approach based on achieving sustainable birth rates.

Tobacco-related mortality among persons with mental health and substance abuse problems.

PubMed

Bandiera, Frank C; Anteneh, Berhanu; Le, Thao; Delucchi, Kevin; Guydish, Joseph

2015-01-01

The rate of cigarette smoking is greater among persons with mental health and/or substance abuse problems. There are few population-based datasets with which to study tobacco mortality in these vulnerable groups. The Oregon Health Authority identified persons who received publicly-funded mental health or substance abuse services from January 1996 through December 2005. These cases were then matched to Oregon Vital Statistics records for all deaths (N= 148,761) in the period 1999-2005. The rate of tobacco-related death rates was higher among persons with substance abuse problems only (53.6%) and those with both substance abuse and mental health problems (46.8%), as compared to the general population (30.7%). The rate of tobacco-related deaths among persons with mental health problems (30%) was similar to that in the general population. Persons receiving substance abuse treatment alone, or receiving both substance abuse and mental health treatment, were more likely to die and more likely to die prematurely of tobacco-related causes as compared to the general population. Persons receiving mental health services alone were not more likely to die of tobacco-related causes, but tobacco-related deaths occurred earlier in this population.

Population Problems, Teacher's Guide. Environmental Education Unit, Twelfth Grade Sociology.

ERIC Educational Resources Information Center

Little Rock School District, AR.

Human population growth and the implications of increasing population on the well-being of men and nations is examined in this twelfth grade curriculum guide which is part of a series for grades 4 through 12. The primary functions of the unit are to introduce the student to reasons for population growth, results of overextended populations, and…

The Nature and Predictors of Undercontrolled and Internalizing Problem Trajectories across Early Childhood

ERIC Educational Resources Information Center

Mathiesen, Kristin S.; Sanson, Ann; Stoolmiller, Mike; Karevold, Evalill

2009-01-01

Using growth curve modeling, trajectories of undercontrolled (oppositional, irritable, inattentive and overactive behaviors) and internalizing (worried, sad and fearful) problems from 18 months to 4.5 years were studied in a population based sample of 921 Norwegian children. At the population level, undercontrolled problems decreased and…

Population: The U.S. Problem--The World Crisis.

ERIC Educational Resources Information Center

Kegan, Lawrence R., Ed.

1972-01-01

Population problems in both the United States and throughout the world are summarized and analyzed, pictorially and narratively, in this special newspaper supplement to "The New York Times", April 30, 1972. Part I presents the U. S. problem, with the following contributions: excerpts from President Richard Nixon's message to Congress on…

Understanding Sleep Disorders in a College Student Population.

ERIC Educational Resources Information Center

Jensen, Dallas R.

2003-01-01

College students' sleep habits are changing dramatically, and related sleep problems are increasing. Reviews the current literature on sleep problems, focusing on the college student population. The unique challenges of college settings are discussed as they apply to understanding sleep problems, and suggestions are made for professionals who work…

Population Geography: Problems, Concepts, and Prospects.

ERIC Educational Resources Information Center

Peters, Gary L.; Larkin, Robert P.

This book introduces secondary students to population geography. Material from other disciplines is included because the study of population is multidisciplinary. It is presented in eleven chapters. The introduction considers definitions of concepts and aspects of population geography, explaining the emphasis on spatial patterns of population…

Some problems of human adaptation and ecology under the aspect of general pathology

NASA Technical Reports Server (NTRS)

Kaznacheyev, V. P.

1980-01-01

The main problems of human adaptation at the level of the body and the population in connection with the features of current morbidity of the population and certain demographic processes are analyzed. The concepts of health and adaptation of the individual and human populations are determined. The importance of the anthropo-ecological approach to the investigation of the adaptation process of human populations is demonstrated. Certain features of the etiopathogenesis of diseases are considered in connection with the population-ecological regularities of human adaptation. The importance of research on general pathology aspects of adaptation and the ecology of man for planning, and organization of public health protection is discussed.

Population problems in Austronesia.

PubMed

Hull, T H

1986-11-01

The author examines population issues facing countries in Oceania and Southeastern Asia. "Analysis is based on recently released population projections from the United Nations Population Division. There are great differences among the countries.... There are nonetheless important areas of commonality: all nations are facing the problem of raising levels of schooling in line with parents' aspirations and economic needs, all face problems of caring for a rising proportion of aged, and all have difficulties with the monitoring and control of international migration. Also, since minority groups in many countries are majority polities in neighbouring states, there is potential for establishing international dialogues aimed at relieving internal tensions." Consideration is given to the role of Australia in promoting international cooperation to deal with these issues. excerpt

Sleep Problems in Children with Autism Spectrum Problems: A Longitudinal Population-Based Study

ERIC Educational Resources Information Center

Sivertsen, Borge; Posserud, Maj-Britt; Gillberg, Christopher; Lundervold, Astri J.; Hysing, Mari

2012-01-01

This study examined the prevalence and chronicity of sleep problems in children who manifest problems believed to be typical of Autism Spectrum Disorders (ASD). Using data from a longitudinal total population study, symptoms of ASD, insomnia and potential explanatory factors were assessed at ages 7-9 and 11-13. Children were included in a group…

Curriculum Development in Population Education. Abstract-Bibliography, Series 6.

ERIC Educational Resources Information Center

United Nations Educational, Scientific, and Cultural Organization, Bangkok (Thailand). Regional Office for Education in Asia and the Pacific.

Part of a series of annotated bibliographies dealing with issues and problems raised by educators involved with population education programs, this publication addresses curriculum development in population education. Curriculum development is the most important component of a population education program, for it is through curriculum materials…

Population Research.

ERIC Educational Resources Information Center

National Inst. of Child Health and Human Development (NIH), Bethesda, MD.

The scope of population research as carried on by the National Institute of Child Health and Human Development (NICHD) is set forth in this booklet. Population problems of the world, United States, and the individual are considered along with international population policies based on voluntary family planning programs. NICHD goals for biological…

Population Education in Africa. English Version.

ERIC Educational Resources Information Center

Sankale-Semeteys, Eva, Ed.

1985-01-01

National conferences on population and development have recommended the integration of population issues into development planning by national governments. This book presents several ideas of practitioners in the field of population and family life education. Five articles in Part I focus on solutions to problems of introducing population…

A Review of Intervention Programs to Prevent and Treat Behavioral Problems in Young Children with Developmental Disabilities

PubMed Central

Petrenko, Christie L. M.

2013-01-01

Children with developmental disabilities are at higher risk for internalizing and externalizing behavioral problems than children in the general population. Effective prevention and treatment programs are necessary to reduce the burden of behavioral problems in this population. The current review identified 17 controlled trials of nine intervention programs for young children with developmental disabilities, with parent training the most common type of intervention in this population. Nearly all studies demonstrated medium to large intervention effects on child behavior post-intervention. Preliminary evidence suggests interventions developed for the general population can be effective for children with developmental disabilities and their families. A greater emphasis on the prevention of behavior problems in young children with developmental disabilities prior to the onset of significant symptoms or clinical disorders is needed. Multi-component interventions may be more efficacious for child behavior problems and yield greater benefits for parent and family adjustment. Recommendations for future research directions are provided. PMID:24222982

Locomotor problems among rural elderly population in a District of Aligarh, North India.

PubMed

Maroof, Mohd; Ahmad, Anees; Khalique, Najam; Ansari, M Athar

2017-01-01

Locomotor functions decline with the age along with other physiological changes. This results in deterioration of the quality of life with decreased social and economic role in the society, as well as increased dependency, for the health care and other basic services. The demographic transition resulting in increased proportion of elderly may pose a burden to the health system. To find the prevalence of locomotor problems among the elderly population, and related sociodemographic factors. The study was a community-based cross-sectional study done at field practice area of Rural Health Training Centre, JN Medical College, AMU, Aligarh, Uttar Pradesh, India. A sample of 225 was drawn from 1018 elderly population aged 60 years and above using systematic random sampling with probability proportionate to size. Sociodemographic characteristics were obtained using pretested and predesigned questionnaire. Locomotor problems were assessed using the criteria used by National Sample Survey Organization. Data were analyzed using SPSS version 20. Chi-square test was used to test relationship of locomotor problems with sociodemographic factors. P <0.05 was considered statistically significant. The prevalence of locomotor problems among the elderly population was 25.8%. Locomotor problems were significantly associated with age, gender, and working status whereas no significant association with literacy status and marital status was observed. The study concluded that approximately one-fourth of the elderly population suffered from locomotor problems. The sociodemographic factors related to locomotor problems needs to be addressed properly to help them lead an independent and economically productive life.

Violence Reported by the Immigrant Population Is High as Compared with the Native Population in Southeast Spain

ERIC Educational Resources Information Center

Colorado-Yohar, S.; Tormo, M. J.; Salmeron, D.; Dios, S.; Ballesta, M.; Navarro, C.

2012-01-01

Immigrants constitute a population vulnerable to the problem of violence. This study sought to ascertain the prevalence of violence reported by the immigrant population in the Murcian Region of Spain and characterize the related factors, taking the country population as reference. A cross-sectional study was carried out based on a representative…

Robust set-point regulation for ecological models with multiple management goals.

PubMed

Guiver, Chris; Mueller, Markus; Hodgson, Dave; Townley, Stuart

2016-05-01

Population managers will often have to deal with problems of meeting multiple goals, for example, keeping at specific levels both the total population and population abundances in given stage-classes of a stratified population. In control engineering, such set-point regulation problems are commonly tackled using multi-input, multi-output proportional and integral (PI) feedback controllers. Building on our recent results for population management with single goals, we develop a PI control approach in a context of multi-objective population management. We show that robust set-point regulation is achieved by using a modified PI controller with saturation and anti-windup elements, both described in the paper, and illustrate the theory with examples. Our results apply more generally to linear control systems with positive state variables, including a class of infinite-dimensional systems, and thus have broader appeal.

Africa's Expanding Population: Old Problems, New Policies.

ERIC Educational Resources Information Center

Goliber, Thomas J.

1989-01-01

Sub-Saharan Africa faces a historic challenge: to achieve economic and social progress while experiencing extraordinary population growth. With an estimated 1989 population of 512 million, the 42 countries of sub-Saharan Africa have the highest birth and death rates of any major world region. Throughout the region, population has outstripped…

Estimating inbreeding rates in natural populations: addressing the problem of incomplete pedigrees

Treesearch

Mark P. Miller; Susan M. Haig; Jonathan D. Ballou; Ashley Steel

2017-01-01

Understanding and estimating inbreeding is essential for managing threatened and endangered wildlife populations. However, determination of inbreeding rates in natural populations is confounded by incomplete parentage information. We present an approach for quantifying inbreeding rates for populations with incomplete parentage information. The approach exploits...

Presence/absence as a metric for monitoring vertebrate populations

Treesearch

Len Ruggiero; Dean Pearson

2000-01-01

Developing cost effective methods for monitoring vertebrate populations is a persistent problem in wildlife biology. Population demographic data is too costly and time intensive to acquire, so researchers have begun investigating presence/absence sampling as a means for monitoring wildlife populations. We examined three important assumptions regarding the probability...

Food in health security in North East Asia.

PubMed

Moon, Hyun-Kyung

2009-01-01

Food and health security in North East Asia including South Korea, North Korea, China and Japan was compared. Because this region contains countries with many complex problems, it is worthwhile to study the current situation. With about 24% of the world's population, all North East Asian countries supply between 2400 and 3000 Kcal of energy. Regarding health status, two extreme problems exist. One is malnutrition in North Korea and China and the other is chronic degenerative disease in Japan, South Korea and China. Because quality, quantity and safety of the food supply have to be secured for health security, some topics are selected and discussed. 1) World food price can have an effect on food security for countries with a low food self sufficiency rate such as Japan and Korea; specially, for the urban poor. 2) Population aging can increase the number of aged people without food security. An aged population with less income and no support from their off-spring, because of disappearing traditional values, may have food insecurity. 3) Population growth and economic growth in this region may worsen food problems. Since a quarter of the world's population resides in this region, populations will continue to increase. With economic growth, people will consume more animal products. 4) Climate change generates food production problems. As the progress of industry continues, there will be less land for food and more pollutants in the environment. 5) Political instability will cause food insecurity and conflict will cause problems with regard to food aid.

Population and development problems: a critical assessment of conventional wisdom. The case of Zimbabwe.

PubMed

Sibanda, A E

1988-01-01

Conventional wisdom, as reflected in reports by the World Bank and the Whitsun Foundation, maintains that control of population growth is the key strategy for stimulating socioeconomic development and ending widespread poverty. The Witsun Foundation has criticized the Government of Zimbabwe for failing to include specific policies for population control in its National Transitional Development Plan. the report further expressed alarm about future availability of land to contain Zimbabwe's growing population. Communal areas are designed for a maximum of 325,000 families yet presently contain 700-800,000 families. This Malthusian, deterministic emphasis on population growth as the source of social ills ignores the broader, complex set of socioeconomic, historical, and political factors that determine material life. Any analysis of population that fails to consider the class structure of society, the type of division of labor, and forms of property and production can produce only meaningless abstractions. For example, consideration of crowding in communal areas must include consideration of inequitable patterns of land ownership in sub-Saharan Africa. Unemployment must be viewed within the context of a capitalist economic structure that relies on an industrial reserve army of labor to ensure acceptance of low wages and labor-intensive conditions. While it is accepted that population growth is creating specific and real problems in Zimbabwe and other African countries, these problems could be ameliorated by land reform and restructuring of the export-oriented colonial economies. Similarly, birth control should not be promoted as the solution to social problems, yet family planning services should be available to raise the status of women. Literacy, agrarian reform, agricultural modernization, and industrialization campaigns free from the dominance of Western capitalism represent the true solutions to Zimbabwe's problems.

Mathematics and Demography.

ERIC Educational Resources Information Center

Schwartz, Richard

1992-01-01

Suggests that teachers use mathematics problems related to the "1992 World Population Data Sheet" to teach students about such population-related issues as hunger, resource scarcity, poverty, and pollution. Offers sample problems involving percents, ratios, basic calculations, sequences, variability, graphs, averages, and correlation. Includes a…

The environmental zero-point problem in evolutionary reaction norm modeling.

PubMed

Ergon, Rolf

2018-04-01

There is a potential problem in present quantitative genetics evolutionary modeling based on reaction norms. Such models are state-space models, where the multivariate breeder's equation in some form is used as the state equation that propagates the population state forward in time. These models use the implicit assumption of a constant reference environment, in many cases set to zero. This zero-point is often the environment a population is adapted to, that is, where the expected geometric mean fitness is maximized. Such environmental reference values follow from the state of the population system, and they are thus population properties. The environment the population is adapted to, is, in other words, an internal population property, independent of the external environment. It is only when the external environment coincides with the internal reference environment, or vice versa, that the population is adapted to the current environment. This is formally a result of state-space modeling theory, which is an important theoretical basis for evolutionary modeling. The potential zero-point problem is present in all types of reaction norm models, parametrized as well as function-valued, and the problem does not disappear when the reference environment is set to zero. As the environmental reference values are population characteristics, they ought to be modeled as such. Whether such characteristics are evolvable is an open question, but considering the complexity of evolutionary processes, such evolvability cannot be excluded without good arguments. As a straightforward solution, I propose to model the reference values as evolvable mean traits in their own right, in addition to other reaction norm traits. However, solutions based on an evolvable G matrix are also possible.

A call for action on disarmament and population.

PubMed

Fukuda, T

1994-08-01

Takeo Fukuda, former prime minister of Japan, opened the 12th session of the InterAction Council in Dresden, Germany, with a speech on June 7, 1994. The council has three priority concerns: world peace and disarmament; global problems of population increase, environmental degradation, resource and energy questions; and the question of activating the world economy. The cold war structure has crumbled, but stockpiled nuclear weapons still pose a threat to the world. Under such a situation, the role of multilateral organizations, particularly the UN, has become increasingly important. The world's political management henceforth should encompass North-South-East-West, the entire world, and multilateral institutions should be further strengthened. Special attention should be paid to the neglected North-South relations. The emergence of the mass-consumption society has generated the era of finite resources and environment. The rapidly increasing global population further complicates this issue. Unless the global problems of population, environment, resources, and energy are alleviated, the future for posterity is dubious. The population of the world is increasing by 100 million each year. It was 1.6 billion at the beginning of this century, but it is expected to increase to 6.4 billion at the end of the century, to 8 billion by the year 2020, and to 10 billion by 2050. Resources, energy, environment, and global population are mutually linked; the problem of balancing the rapidly increasing population and the food supply must be addressed. The hope is that the Food and Agriculture Organization will come up with measures to cope with this problem by forecasting the food supply and demand and population. The InterAction Council will hold its 13th session in Tokyo in 1995.

An Analysis of Communication as a Key Component in Leadership with Diverse School Populations

ERIC Educational Resources Information Center

Cagle, Jo E.; Wiley, Sandy T.

2012-01-01

"Effective Communication as an Essential Element of Leaders with Diverse School Populations" describes a problem based learning project focused on issues related to practices used by principals to address diverse school populations. The team found that communication between principals and diverse populations in schools was a challenge.…

Guide to Population Issues for Students and Teachers [and] Curriculum Guide.

ERIC Educational Resources Information Center

Facing the Future, Lopez Island, WA.

As the world grapples with increasing environmental, social, and security problems, population is rarely considered a cause or contributing factor. The relationship of population to the human condition, and to the condition of the Earth, is often subtle and complex. But population growth affects almost every aspect of life from education to…

Population Education in the Nineties: A Quest for a Regional Programme Strategy in Asia and the Pacific.

ERIC Educational Resources Information Center

Population Education in Asia and the Pacific Newsletter and Forum, 1991

1991-01-01

This study is a response to the emerging needs and requirements for population management with respect to regional strategies for population education. Addresses problems of illiteracy, poverty, and other impediments to population-growth management through the further training of those involved in the education process. (MCO)

Monitoring trends in bat populations of the United States and territories: Problems and prospects

USGS Publications Warehouse

O'Shea, T.J.; Bogan, M. A.

2003-01-01

Bats are ecologically and economically important mammals. The life histories of bats (particularly their low reproductive rates and the need for some species to gather in large aggregations at limited numbers of roosting sites) make their populations vulnerable to declines. Many of the species of bats in the United States (U.S.) and territories are categorized as endangered or threatened, have been candidates for such categories, or are considered species of concern. The importance and vulnerability of bat populations makes monitoring trends in their populations a goal for their future management. However, scientifically rigorous monitoring of bat populations requires well-planned, statistically defensible efforts. This volume reports findings of an expert workshop held to examine the topic of monitoring populations of bats. The workshop participants included leading experts in sampling and analysis of wildlife populations, as well as experts in the biology and conservation of bats. Findings are reported in this volume under two sections. Part I of the report presents contributed papers that provide overviews of past and current efforts at monitoring trends in populations of bats in the U.S. and territories. These papers consider current techniques and problems, and summarize what is known about the status and trends in populations of selected groups of bats. The contributed papers in Part I also include a description of the monitoring program developed for bat populations in the United Kingdom, a critique of monitoring programs in wildlife in general with recommendations for survey and sampling strategies, and a compilation and analysis of existing data on trends in bats of the U.S. and territories. Efforts directed at monitoring bat populations are piecemeal and have shortcomings. In Part II of the report, the workshop participants provide critical analyses of these problems and develop recommendations for improving methods, defining objectives and priorities, gaining mandates, and enhancing information exchange to facilitate future efforts for monitoring trends in U.S. bat populations.

Population and Pollution in the United States

ERIC Educational Resources Information Center

Ridker, Ronald G.

1972-01-01

Analyzes a simple model relating environmental pollution to population and per capita income and concludes that no single cause is sufficient to explain.... environmental problems, and that there is little about the pollution problems.... of the next 50 years that is inevitable." (Author/AL)

Teaching Demography to Undergraduates: A Pedagogical Dilemma.

ERIC Educational Resources Information Center

Abowitz, Deborah A.

1990-01-01

Describes a course based on the interdisciplinary approach to demography linked to environmental issues. Analytic and interpretive skills are an integral element in the study of population-related problems. Points out that the interdisciplinary approach maintains demographic literacy while analyzing population problems. (SLM)

An examination of problem-based teaching and learning in population genetics and evolution using EVOLVE, a computer simulation

NASA Astrophysics Data System (ADS)

Soderberg, Patti; Price, Frank

2003-01-01

This study describes a lesson in which students engaged in inquiry in evolutionary biology in order to develop a better understanding of the concepts and reasoning skills necessary to support knowledge claims about changes in the genetic structure of populations, also known as microevolution. This paper describes how a software simulation called EVOLVE can be used to foster discussions about the conceptual knowledge used by advanced secondary or introductory college students when investigating the effects of natural selection on hypothetical populations over time. An experienced professor's use and rationale of a problem-based lesson using the simulation is examined. Examples of student misconceptions and naïve (incomplete) conceptions are described and an analysis of the procedural knowledge for experimenting with the computer model is provided. The results of this case study provide a model of how EVOLVE can be used to engage students in a complex problem-solving experience that encourages student meta-cognitive reflection about their understanding of evolution at the population level. Implications for teaching are provided and ways to improve student learning and problem solving in population genetics are suggested.

Visualizing diurnal population change in urban areas for emergency management.

PubMed

Kobayashi, Tetsuo; Medina, Richard M; Cova, Thomas J

2011-01-01

There is an increasing need for a quick, simple method to represent diurnal population change in metropolitan areas for effective emergency management and risk analysis. Many geographic studies rely on decennial U.S. Census data that assume that urban populations are static in space and time. This has obvious limitations in the context of dynamic geographic problems. The U.S. Department of Transportation publishes population data at the transportation analysis zone level in fifteen-minute increments. This level of spatial and temporal detail allows for improved dynamic population modeling. This article presents a methodology for visualizing and analyzing diurnal population change for metropolitan areas based on this readily available data. Areal interpolation within a geographic information system is used to create twenty-four (one per hour) population surfaces for the larger metropolitan area of Salt Lake County, Utah. The resulting surfaces represent diurnal population change for an average workday and are easily combined to produce an animation that illustrates population dynamics throughout the day. A case study of using the method to visualize population distributions in an emergency management context is provided using two scenarios: a chemical release and a dirty bomb in Salt Lake County. This methodology can be used to address a wide variety of problems in emergency management.

[Commentary on "group and organization: a dimension of collaboration of anthropology and epidemiology" by Song LM and Wang N].

PubMed

Liao, Su-Su; Zhang, Qing-Ning; Hou, Lei

2012-10-01

Epidemiology, as the study of occurrence and distribution of diseases or health events in specified populations and the application of the study to control health problems, is not just a method to study determinants of diseases at individual level through analysis of mass data based on individuals. To achieve the aims on the control of health problems in specified populations, Epidemiology should be public health-oriented to reduce incidence, prevalence and mortality, and should include study on determinants at the population level. Interdisplinarity and systems science will facilitate the breakthrough in improving health of the populations.

The developmental implications of migration from and between small island nations.

PubMed

Mckee, D L; Tisdell, C A

1988-12-01

This article discusses the role of migration in relieving population pressures, thus making continuing development possible, using small nations in the Caribbean and the South Pacific as examples. The Caribbean islands and many Pacific islands have used out-migration to ease population pressures in this century. Surplus labor has been emerging in various Caribbean nations, independent of the international marketing problems of plantation agriculture. Rural populations alienated from plantations have had to make do on questionable and/or remote land. Population surpluses appear to originate in rural areas, but little evidence exists to suggest that those surpluses are the basis for the emigration patterns of the Caribbean islands. Emigration does not solve population problems because when ambitious, skilled workers leave their country, their actions have little to do with the existence of domestic surplus labor and their leaving may do little to facilitate domestic labor absorption. Thus, if mini-states wish to sustain their hopes of economic expansion, they must find the means to employ their surplus labor. Since mainly skilled migrants leave, their going may actually slow development and retard opportunities for labor absorption. Population movements internal to the Caribbean region may further complicate surplus labor and/or population problems. If protective entry requirements impede normal inter-island relations, they may interfere with developmental processes. In general, migration is not a feasible strategy for population control for small island nations. While temporary migration has a more positive impact than other forms of migration, problems do exist. For example, temporary migration 1) can impose significant economic costs on the source-country, and 2) may result in the source country being unable to capitalize on its initial investment in training and education of temporary migrants. In conclusion, import substitution through cooperation between small island nations, production for export where feasible, and more attention to more sophisticated international service linkages hold a better prospect for material progress than relying on the export of surplus populations.

Wild pig populations in the National Parks

NASA Astrophysics Data System (ADS)

Singer, Francis J.

1981-05-01

Populations of introduced European wild boar, feral pigs, and combinations of both types (all Sus scrola L.) inhabit thirteen areas in the National Park Service system. All parks have relatively stable populations, with the exception of Great Smoky Mountains National Park, which reported a rapidly expanding wild boar population. Suspected and documented impacts were apparently related to pig densities and sensitivity of the ecosystem; the three largest units with dense wild pig populations reported the most damage. Overall, wild pigs are a relatively minor problem for the Park Service; however, problems are severe in at least three parks, and there is potential for invasion of wild boars into several additional parks in the Appalachian Mountains. More specific information is needed on numbers of wild pigs and their impacts in the various parks.

Sociological research on the population awareness regarding ophthalmological care in ukraine.

PubMed

Ieremeieva, Tetiana V

nowadays, there are about 45 million blind individuals and, according to the prognosis, their quantity will reach over 76 million in 2020. In such a way, nowadays ophthalmological problems become more widespread, and the market of the ophthalmological services is not studied enough to understand all the tendencies and processes. was to study the patients' awareness on eye diseases and choice peculiarities of the information sources and medical institutions among various population age groups of Lutsk, Rivne and Ternopil cities. the research was conducted as an anonymous questionnaire survey of respondents according to a specially designed integrated protocol by means of interviewing people at the streets of Lutsk (n=2000), Rivne (n=1500) and Ternopil (n=1500) cities. there was conducted a research on the population awareness concerning vision problems, analysis of social factors and peculiarities of the choice of information sources about eye diseases and factors influencing the choice of a medical institution and an ophthalmologist. It was determined that younger population prefers private medical institutions in almost half of the cases (95% confidence interval (CI) of the private institution choice probability: 0,48-0,52), while older population prefers mainly state ones (95% CI of the choice probability: 0,71-0,74). it was determined depending on the age, the range of people having vision problems varied from 22% in the "under 30 years" population group up to 76% in the "over 60 years" group, although at least 21,5% of the whole population realizing their problems do not address an ophthalmologist.

Sociological research on the population awareness regarding ophthalmological care in ukraine.

PubMed

Ieremeieva, Tetiana V

2016-01-01

nowadays, there are about 45 million blind individuals and, according to the prognosis, their quantity will reach over 76 million in 2020. In such a way, nowadays ophthalmological problems become more widespread, and the market of the ophthalmological services is not studied enough to understand all the tendencies and processes. was to study the patients' awareness on eye diseases and choice peculiarities of the information sources and medical institutions among various population age groups of Lutsk, Rivne and Ternopil cities. the research was conducted as an anonymous questionnaire survey of respondents according to a specially designed integrated protocol by means of interviewing people at the streets of Lutsk (n=2000), Rivne (n=1500) and Ternopil (n=1500) cities. there was conducted a research on the population awareness concerning vision problems, analysis of social factors and peculiarities of the choice of information sources about eye diseases and factors influencing the choice of a medical institution and an ophthalmologist. It was determined that younger population prefers private medical institutions in almost half of the cases (95% confidence interval (CI) of the private institution choice probability: 0,48-0,52), while older population prefers mainly state ones (95% CI of the choice probability: 0,71-0,74). it was determined depending on the age, the range of people having vision problems varied from 22% in the "under 30 years" population group up to 76% in the "over 60 years" group, although at least 21,5% of the whole population realizing their problems do not address an ophthalmologist.

Unique Problems of the Inner City Colleges.

ERIC Educational Resources Information Center

Lombardi, John

Urban changes such as population increase, shifts in population groups, suburban growth, and central city decay have produced special problems for the inner city college--de facto segregation, inadequate education programs, racial imbalance of employees, and discrimination in student participant activities. The attempts to prevent…

World Population: U.N. on the Move but Grounds for Optimism Are Scant

ERIC Educational Resources Information Center

Holden, Constance

1974-01-01

Discusses current trends and problems relating to world population, and focuses on action being taken by the United Nations. This year (1974) has been designated World Population Year, and will be highlighted by a conference in Bucharest in which all 130 member governments will meet to confront the issue of population control. (JR)

Social problems and health in urbanization.

PubMed

Talib, R; Agus, M R

1992-01-01

One of the main characteristics of urbanization in Asia is the very rapid increase in population movement from rural to urban centers. This phenomenon has led to changing population structure, its composition and lifestyles in the cities and its fringes. As a consequent of population pressure on urban system and infrastructure, compounded by the nature of the composition of the in-migrant population, the urban concentrates are faced with several social and socio-economic problems. Although there has been a lot of interests among researchers to study the causes and effects or urbanization, there is a vacuum in the area of health implications. Planners and administrators usually give priority to the physical aspects of the urban and urbanities. Social problems and health implications thereof receives very little attention either at the level of administration or research. This paper therefore is a brave attempt to focus and draw some attention to this neglected area by looking at selected social problems and the health consequences.

Eating Problems and Their Risk Factors: A 7-Year Longitudinal Study of a Population Sample of Norwegian Adolescent Girls

ERIC Educational Resources Information Center

Kansi, Juliska; Wichstrom, Lars; Bergman, Lars R.

2005-01-01

The longitudinal stability of eating problems and their relationships to risk factors were investigated in a representative population sample of 623 Norwegian girls aged 13-14 followed over 7 years (3 time points). Three eating problem symptoms were measured: Restriction, Bulimia-food preoccupation, and Diet, all taken from the 12-item Eating…

Healthcare and Guidelines: A Population-Based Survey of Recorded Medical Problems and Health Surveillance for People with Down syndrome

ERIC Educational Resources Information Center

Maatta, Tuomo; Maatta, Joonas; Tervo-Maatta, Tuula; Taanila, Anja; Kaski, Markus; Iivanainen, Matti

2011-01-01

Background: Medical problems are described in a population of persons with Down syndrome. Health surveillance is compared to the recommendations of national guidelines. Method: Case records from the specialised and primary healthcare and disability services were analysed. Results: A wide spectrum of age-specific medical and surgical problems was…

Unhealthy drinking in the Belgian elderly population: prevalence and associated characteristics.

PubMed

Hoeck, Sarah; Van Hal, Guido

2013-12-01

Knowledge about alcohol consumption patterns and alcohol problems among the Belgian elderly population is scarce. The aims of this study were to explore alcohol consumption patterns and alcohol problems among the Belgian elderly population aged ≥ 65 years living at home, and to determine their association with socio-demographic characteristics, health status and socio-economic status. In this cross-sectional study based on a representative sample of 4825 non-institutionalized Belgian elderly people (≥ 65 years) in the Belgian Health Interview Surveys 2001 and 2004, alcohol consumption patterns and alcohol problems were estimated according to age, gender, survey year, living situation, frequency of social contacts, smoking status, and socio-economic status. In all, 50.4% of the sample were non- or occasional drinkers, 29.1% were moderate drinkers, 10.4% at-risk drinkers, 4.6% heavy drinkers and 5.5% problematic drinkers. In total, 20.5% of the Belgian elderly population drank in excess of the National Institute on Alcohol Abuse and Alcoholism guidelines, and 4.7% had an alcohol problem according to the CAGE. In addition, 81.3% of the elderly people who consume alcohol used prescribed medications in the past 2 weeks. After adjustment for risk factors we found that, compared with moderate drinking, unhealthy drinking was significantly associated with age, gender, frequency of social contacts, health status and socio-economic status. Belgian health policy should be aware of the high level of at-risk drinkers in the elderly population and the underdetection and misdiagnosis of alcohol problems in this age group. An increased attention in public health initiatives among the Belgian elderly population is needed.

Correlates of conflict, power and authority management, aggression and impulse control in the Jamaican population.

PubMed

Walcott, G; Hickling, F W

2013-01-01

The object of this study is to establish the correlates of the phenomenology of conflict and power management in the Jamaican population. A total of 1506 adult individuals were sampled from 2150 households using a stratified sampling method and assessed using the 12 questions of the Jamaica Personality Disorder Inventory (JPDI) on the phenomenology of conflict and power management that are grouped into the psychological features of aggressive social behaviour, unlawful behaviour, socially unacceptable behaviour and financial transgressive behaviour. The database of responses to the demographic and JPDI questionnaires was created and analysed using the Statistical Package for the Social Sciences (SPSS) version 17. Of the national population sampled, 69.1% denied having any phenomenological symptoms of abnormal power management relations while 30.9% of the population admitted to having some degree of conflict and power management, ranging from mild (10.3%), to moderate (17.1), or severe (3.5%). There were 46.55% of the population which had problems with aggressive social behaviour, 9.33% had problems with unlawful behaviour, 9.58% had problems with unacceptable social behaviour and 37.74% had problems with financial transgressive behaviour. Significant gender and socio-economic class patterns for conflict and power management were revealed. This pattern of conflict and power management behaviour is critical in understanding the distinction between normal and abnormal expression of these emotions and actions. Nearly one-third of the sample population ` studied reported problems with conflict, abnormal power and authority management, impulse control and serious aggressive and transgressive behaviour.

Migration from rural to urban habitat in Tropical Africa (1970-2000).

PubMed

Ankerl, G G

1982-01-01

Problems associated with rural-urban migration in Tropical Africa are examined, with particular reference to the experience of Ghana, Kenya, Nigeria, Tanzania, and Zaire. The problems examined include overurbanization, maldistribution of population, poor urban living conditions, population density, and traditional methods of construction.

The Problem is People, Social Studies: 6425.07.

ERIC Educational Resources Information Center

Ratchford, Frank

Population education is the focus of this quinmester curriculum guide for secondary students. By examining and comparing past population theories of Malthus and Marx with present theories students will better understand the present situation, cultural attitudes toward the problems, and the ecological consequences of overpopulation. Objectives are…

Combinatorial optimization problem solution based on improved genetic algorithm

NASA Astrophysics Data System (ADS)

Zhang, Peng

2017-08-01

Traveling salesman problem (TSP) is a classic combinatorial optimization problem. It is a simplified form of many complex problems. In the process of study and research, it is understood that the parameters that affect the performance of genetic algorithm mainly include the quality of initial population, the population size, and crossover probability and mutation probability values. As a result, an improved genetic algorithm for solving TSP problems is put forward. The population is graded according to individual similarity, and different operations are performed to different levels of individuals. In addition, elitist retention strategy is adopted at each level, and the crossover operator and mutation operator are improved. Several experiments are designed to verify the feasibility of the algorithm. Through the experimental results analysis, it is proved that the improved algorithm can improve the accuracy and efficiency of the solution.

Estimating Kinship in Admixed Populations

PubMed Central

Thornton, Timothy; Tang, Hua; Hoffmann, Thomas J.; Ochs-Balcom, Heather M.; Caan, Bette J.; Risch, Neil

2012-01-01

Genome-wide association studies (GWASs) are commonly used for the mapping of genetic loci that influence complex traits. A problem that is often encountered in both population-based and family-based GWASs is that of identifying cryptic relatedness and population stratification because it is well known that failure to appropriately account for both pedigree and population structure can lead to spurious association. A number of methods have been proposed for identifying relatives in samples from homogeneous populations. A strong assumption of population homogeneity, however, is often untenable, and many GWASs include samples from structured populations. Here, we consider the problem of estimating relatedness in structured populations with admixed ancestry. We propose a method, REAP (relatedness estimation in admixed populations), for robust estimation of identity by descent (IBD)-sharing probabilities and kinship coefficients in admixed populations. REAP appropriately accounts for population structure and ancestry-related assortative mating by using individual-specific allele frequencies at SNPs that are calculated on the basis of ancestry derived from whole-genome analysis. In simulation studies with related individuals and admixture from highly divergent populations, we demonstrate that REAP gives accurate IBD-sharing probabilities and kinship coefficients. We apply REAP to the Mexican Americans in Los Angeles, California (MXL) population sample of release 3 of phase III of the International Haplotype Map Project; in this sample, we identify third- and fourth-degree relatives who have not previously been reported. We also apply REAP to the African American and Hispanic samples from the Women's Health Initiative SNP Health Association Resource (WHI-SHARe) study, in which hundreds of pairs of cryptically related individuals have been identified. PMID:22748210

Integrating host, natural enemy, and other processes in population models of the pine sawfly

Treesearch

A. A. Sharov

1991-01-01

Explanation of population dynamics is one of the main problems in population ecology. There are two main approaches to the explanation: the factor approach and the dynamic approach. According to the first, an explanation is obtained when the effect of various environmental factors on population density is revealed. Such analysis is performed using well developed...

Population dynamics and environmental degradation in Nepal: an interpretation.

PubMed

Karki, Y B

1993-01-01

This paper examines the special problems that are faced by developing countries, specifically Nepal, which have to sustain increasing populations from a depleting natural resource base. Nepal is an example of a developing country where fertility is high and mortality is decreasing fast, resulting in a high rate of population growth. Nepal's rapid population growth has had a significant impact on natural resource depletion and consequently, environmental degradation. The case of Nepal demonstrates the difficulties confronting developing countries, which attempt practical implementation of the population policy guidelines set out in Agenda 21. Past and current population programs in this country have failed to address the population problem as multidimensional, and have failed to encourage grassroots participation. Economic stagnation and poverty encourage a large family size, and are delaying declines in fertility which subsequently leads to high land encroachment and fast depletion of natural resources like forests and water. The government needs to implement an integrated, multidimensional approach, which emphasizes literacy, education, lowering infant mortality, and providing contraceptives along with follow-ups. Finally, the greatest action must consist of fostering a higher rate of planned economic and social development that must be shown to have meaning for, and impact on the population in general.

New roads toward North-South cooperation.

PubMed

Terpstra, E G

1989-12-01

A Netherlands Parliament member gives a European Perspective on population and development, problems in urban development, and methods of cooperation between industrialized and developing countries. On population and development, the relationship between population explosion and poverty, underdevelopment, environment, social infrastructure, and food shortages is pointed out. Most population growth in the years ahead will be in developing countries. Rampant population growth and burgeoning poverty strain the world's carrying capacity and environment, both in industrial and developing countries. Development policy and cooperation will fail in the absence of efforts to stem population growth. On this front, religious and political leaders have groundbreaking cooperative steps in supporting international family planning efforts through the global forum of Spiritual and Parliamentary Leaders on Human Survival. Economic development, environment, and population issues are inexorably tied together. The numerous problems faced by uncontrolled Third World urbanization are discussed with potential solutions for change. Incorporating women in the development process is strongly encouraged. The interdependent North-South relationship is discussed. All nations, the private sector, nongovernmental organizations, and women must cooperate to find solutions and effect positive change on a case-by-case basis.

Effects of road mortality and mitigation measures on amphibian populations.

PubMed

Beebee, Trevor J C

2013-08-01

Road mortality is a widely recognized but rarely quantified threat to the viability of amphibian populations. The global extent of the problem is substantial and factors affecting the number of animals killed on highways include life-history traits and landscape features. Secondary effects include genetic isolation due to roads acting as barriers to migration. Long-term effects of roads on population dynamics are often severe and mitigation methods include volunteer rescues and under-road tunnels. Despite the development of methods that reduce road kill in specific locations, especially under-road tunnels and culverts, there is scant evidence that such measures will protect populations over the long term. There also seems little likelihood that funding will be forthcoming to ameliorate the problem at the scale necessary to prevent further population declines. © 2013 Society for Conservation Biology.

Screening for Vision Problems in Children with Hearing Impairments.

ERIC Educational Resources Information Center

Demchak, MaryAnn; Elquist, Marty

Vision problems occur at higher rates in the deaf and hearing impaired population than in the general population. When an individual has a hearing impairment, vision becomes more significant in the instructional and learning process, as well as in social and communicative exchanges. Regular comprehensive visual screening of hearing impaired…

An Artificial Immune System with Feedback Mechanisms for Effective Handling of Population Size

NASA Astrophysics Data System (ADS)

Gao, Shangce; Wang, Rong-Long; Ishii, Masahiro; Tang, Zheng

This paper represents a feedback artificial immune system (FAIS). Inspired by the feedback mechanisms in the biological immune system, the proposed algorithm effectively manipulates the population size by increasing and decreasing B cells according to the diversity of the current population. Two kinds of assessments are used to evaluate the diversity aiming to capture the characteristics of the problem on hand. Furthermore, the processing of adding and declining the number of population is designed. The validity of the proposed algorithm is tested for several traveling salesman benchmark problems. Simulation results demonstrate the efficiency of the proposed algorithm when compared with the traditional genetic algorithm and an improved clonal selection algorithm.

Afghanistan.

PubMed

1983-05-01

In this discussion of Afghanistan, attention focuses on: the history of the country's demographic situation; the government's overall approach to population problems; population data systems and development planning; institutional arrangements for the integration of population within development objectives; population size, growth, and natural increase; morbidity and mortality; fertility; international migration; and spatial distribution. Only recently has there been a population census in the country; consequently, there has been relatively little reliable demographic information available, especially in a historical context. Afghanistan's total population was officially estimated at nearly 16 million in late 1967. According to UN estimates, the population totaled 8.3 million in 1960 and increased to 9.8 and 12.3 million in the following 2 decades to over 14 million by 1975. The rate of population growth, as estimated by the UN, is reported to have increased from 1.6% during 1950-55 to 2.4% by the following decade, reaching 2.9% during 1970-75. The crude birthrate declined slightly from 50.4 births/1000 during 1950-55 to 49.2 during 1970-75. The crude death rate declined from 34.6/1000 to 23.4 deaths/1000 during the same period. Although the rate of population growth is considered to be fairly high, the government does not perceive this as presenting a population problem for the country as a whole since the overall population density is relatively low (approximately 20 persons per square kilometer). A national statistical information system has been developed in Afghanistan over the past decades. The government has no explicit population policy, and a clear association between population and development issues has not been expressed. Policies in the area of population distribution indicate the government's concern with settlement and resettlement of certain segments of the population in connection with the overall economic and social development of sparsely populated areas. The government perceives the current rate of population growth as unsatisfactory because it is too high, but does not view this as presenting any particular population problem. Data on mortality rates based primarily on the 1979 census indicate a crude death rate of 22/1000 for the sedentary population. The government regards the levels off mortality to bbe unacceptable, and its official goal is to rapidly reduce mortality and morbidity. High priority is given to the prevention and treatment of morbidity among young children. The fertility levels are quite high, compared acceptability of these levels. Direct governmental support is givenn to the family planning program in terms of both access to informartion and family planning methods. Levels of immigration are not significant. No official policy concerning the spatial distribution of the population has been formulated.

On a variational approach to some parameter estimation problems

NASA Technical Reports Server (NTRS)

Banks, H. T.

1985-01-01

Examples (1-D seismic, large flexible structures, bioturbation, nonlinear population dispersal) in which a variation setting can provide a convenient framework for convergence and stability arguments in parameter estimation problems are considered. Some of these examples are 1-D seismic, large flexible structures, bioturbation, and nonlinear population dispersal. Arguments for convergence and stability via a variational approach of least squares formulations of parameter estimation problems for partial differential equations is one aspect of the problem considered.

U.S. Population Growth: Prospects and Policy.

ERIC Educational Resources Information Center

McFalls, Joseph A., Jr.; And Others

1984-01-01

The Commission on Population Growth and the American Future concluded that zero population growth (ZPG) is in the best interest of the United States. To achieve ZPG in the future, the United States must keep fertility and net immigration relatively low. Practical problems are discussed. (RM)

Hypertension in Black and Other Populations: Environmental Factors and Approaches to Management

PubMed Central

Hosten, Adrian O.

1980-01-01

Hypertension is a major health problem for industrialized as well as developing countries, especially those with sizeable black populations. The author analyzes various aspects of hypertension in black and other populations with emphasis on contributing factors and therapeutic approaches. PMID:7365811

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

de Vega, F F; Cantu-Paz, E; Lopez, J I

The population size of genetic algorithms (GAs) affects the quality of the solutions and the time required to find them. While progress has been made in estimating the population sizes required to reach a desired solution quality for certain problems, in practice the sizing of populations is still usually performed by trial and error. These trials might lead to find a population that is large enough to reach a satisfactory solution, but there may still be opportunities to optimize the computational cost by reducing the size of the population. This paper presents a technique called plague that periodically removes amore » number of individuals from the population as the GA executes. Recently, the usefulness of the plague has been demonstrated for genetic programming. The objective of this paper is to extend the study of plagues to genetic algorithms. We experiment with deceptive trap functions, a tunable difficult problem for GAs, and the experiments show that plagues can save computational time while maintaining solution quality and reliability.« less

Mental health differences between German gay and bisexual men and population-based controls.

PubMed

Sattler, Frank A; Franke, Gabriele H; Christiansen, Hanna

2017-07-21

International studies have revealed that gay and bisexual men present more mental health problems than the general male population. Furthermore, there is evidence that minority stress predicts mental health problems in gay and bisexual men. The aim of the present study is to provide initial data on mental health differences in Germany and to analyze the effect of minority stress. Mental health data on n = 1903 German gay and bisexual men and n = 958 men from a population-based sample were assessed using a shortened version of the SCL-90-S. The mental health of the two samples was compared. Furthermore, a linear regression was conducted for the gay and bisexual sample: mental health was used as the criterion and minority stressors as predictors. As compared to our population sample, gay and bisexual men demonstrated more mental health problems with a moderate effect size. In the regression, minority stress predicted mental health problems in the gay and bisexual sample. We observed pronounced mental health differences between gay and bisexual men versus the population sample. These differences could be at least partly due to the minority stress gay and bisexual men face. Research should focus on how to reduce and cope with minority stress.

Combining nutrient intake from food/beverages and vitamin/mineral supplements.

PubMed

Garriguet, Didier

2010-12-01

To calculate total intake of a nutrient and estimate inadequate intake for a population, the amounts derived from food/beverages and from vitamin/mineral supplements must be combined. The two methods Statistics Canada has suggested present problems of interpretation. Data collected from 34,386 respondents to the 2004 Canadian Community Health Survey-Nutrition were used to compare four methods of combining nutrient intake from food/beverages and vitamin/mineral supplements: adding average intake from supplements to the 24-hour food/beverage recall and estimating the usual distribution in the population (Method 1); estimating usual individual intake from food? beverages and adding intake from supplements (Method 2); and dividing the population into supplement users and non-users and applying Method 1 or Method 2 and combining the estimates based on the percentages of users and non-users (Methods 3 and 4). Interpretation problems arise with Methods 1 and 2; for example, the percentage of the population with inadequate intake of vitamin C and folate equivalents falls outside the expected minimum-maximum range. These interpretation problems are not observed with Methods 3 and 4. Interpretation problems that may arise in combining food and supplement intake of a given nutrient are overcome if the population is divided into supplement users and non-users before Method 1 or Method 2 is applied.

Future Estimation of Convenience Living Facilities Withdrawal due to Population Decline all Over Japan from 2010 TO 2040 - Focus on Supermarkets, Convenience Stores and Drugstores

NASA Astrophysics Data System (ADS)

Nishimoto, Yuka; Akiyama, Yuki; Shibasaki, Ryosuke

2016-06-01

Population explosion is considered to be one of the most crucial problems in the world. However, in Japan, the opposite problem: population decline has become serious now. Japanese population is estimated to decrease by twenty millions in 2040. This negative situation will cause to increase areas where many residents cannot make a daily living all over Japan because many convenience living facilities such as supermarkets, convenience stores and drugstores will be difficult to maintain their market area population due to future population decline. In our research, we used point data of convenience living facilities developed by address geocoding of digital telephone directory and point data of future population projection developed by distribution of Japanese official population projection data proportionally among the building volume of digital residential map, which can monitor building volumes all over Japan. In conclusion, we estimated that various convenience living facilities in Japan will shrink and close by population decline in near future. In particular, it is cleared that approximately 14.7% of supermarkets will be possible to withdraw all over Japan by 2040. In addition, it is cleared that over 40% of supermarkets in some countryside prefectures will be possible to withdraw by 2040. Thus, we estimated future distributions of convenience living facilities that cannot maintain their market area population due to future population decline. Moreover, we estimated the number of people that they will become inconvenience in buying fresh foods.

[Health problems of working-age population in the Russian Federation].

PubMed

Izmerov, N F; Tikhonova, G I

2010-01-01

The paper deals with health problems of working-age population in the Russian Federation. According to foreign and domestic experts reduction of the able-bodied population and its fraction in the general population will be accompanied by ageing of labour force in the nearest two decades. Despite the growth of life expectancy in 2006-2007 demonstrated by disability, mortality and life expectancy indices for the age group of interest, its health status is considered to be critical. Mathematical simulation of mortality rates allowed for the assessment of potential years of life lost (PYLL) from leading causes of death among active working population. The data obtained provide a basis for the elaboration of medical and social programs aimed at increasing life expectancy. The most essential role in current negative tendencies in the health of active working population belongs to the deterioration of work conditions and safety at industrial enterprises coupled to low efficiency of occupational health prevention system accounting for the significantly reduced accessibility of health services. Restoration of occupational health system in Russia is of crucial importance. Experts of the Institute of Occupational Health have elaborated a draft National Action Plan designed to improve health protection of labour force in this country; its implementation would help to solve demographic problems and increase the amount and quality of labour force.

[Population changes and social welfare tasks].

PubMed

Lee, H K

1985-07-01

Efforts to control population growth made during the last 20 years are expected to maintain a stable population in the future. We cannot limit our concern to the control of population growth but must consider the social welfare task in the aspect of population stability. It is not because population changes set limits to artificial control, but because the order of population changes presents a desirable sign for low fertility. Another important concern is to pay attention to how to make human beings already born and those to be born in the future enjoy their quality of life. Socioeconomic stability requires economic stabilization to meet basic essential needs. Changes in population structure, along with the quantitative growth of population, make changes in patterns of social welfare demands. When the pyramid type of population structure becomes changed to the bell or pot type of population structure, changes in education and employment as well as changes in problems of the aged and medical demands must be made. On the other hand, population changes accompany value changes in the process of modernization of society. These multiple social changes bring about a value of individualism and a nuclear family norm, and an enlargement of women's social participation which, in turn, can cause family problems. At the same time, social deviations and failures may be increased in the industrial society, and, thus, welfare countermeasures have to be taken. In this respect, the base of social welfare for meeting basic demands must be formed not in the past, narrow sense but in the long range and multisided aspects.

Trust of Population within Social Relations System of the Population: A Case Study of Nasleg Administration in the Republic of Sakha (Yakutia)

ERIC Educational Resources Information Center

Mikhaylova, Anna; Popova, Liudmila

2016-01-01

The research consists in studying the level of population's trust in nasleg administration (in the administrative-territorial unit) of MS "Khatyryksky nasleg" of Namsky ulus using the case study. The leading research methods for the problem are empirical methods that allow revealing the level of population's trust in administration. The…

Family size and effective population size in a hatchery stock of coho salmon (Oncorhynchus kisutch)

USGS Publications Warehouse

Simon, R.C.; McIntyre, J.D.; Hemmingsen, A.R.

1986-01-01

Means and variances of family size measured in five year-classes of wire-tagged coho salmon (Oncorhynchus kisutch) were linearly related. Population effective size was calculated by using estimated means and variances of family size in a 25-yr data set. Although numbers of age 3 adults returning to the hatchery appeared to be large enough to avoid inbreeding problems (the 25-yr mean exceeded 4500), the numbers actually contributing to the hatchery production may be too low. Several strategies are proposed to correct the problem perceived. Argument is given to support the contention that the problem of effective size is fairly general and is not confined to the present study population.

Preliminary assessment of aerial photography techniques for canvasback population analysis

USGS Publications Warehouse

Munro, R.E.; Trauger, D.L.

1976-01-01

Recent intensive research on the canvasback has focused attention on the need for more precise estimates of population parameters. During the 1972-75 period, various types of aerial photographing equipment were evaluated to determine the problems and potentials for employing these techniques in appraisals of canvasback populations. The equipment and procedures available for automated analysis of aerial photographic imagery were also investigated. Serious technical problems remain to be resolved, but some promising results were obtained. Final conclusions about the feasibility of operational implementation await a more rigorous analysis of the data collected.

Concurrent Mental Health and Substance Use Problems among Street-Involved Youth

ERIC Educational Resources Information Center

Kirst, Maritt; Frederick, Tyler; Erickson, Patricia G.

2011-01-01

Among marginalized populations, homeless adults are known to have elevated rates of mental health and substance use problems compared to the general population, but less is known about their youthful homeless counterparts. While few studies currently exist, what research has been conducted among street-involved youth has confirmed high rates of…

Older Women: A Population at Risk for Mental Health Problems.

ERIC Educational Resources Information Center

Wisniewski, Wendy; Cohen, Donna

The expanding population of older women relative to older men or the "feminization of aging" is a significant demographic trend with important implications for the future. Older women are at risk for extended years of widowhood, living alone, institutionalization, poverty, and mental health problems. Although the dementias of late life appear to…

Chile: Political and Economic Conditions and U.S. Relations

DTIC Science & Technology

2009-06-03

6 Mapuche Activism...education, which they contend is the root problem.26 Mapuche Activism Confrontation with the Mapuche population has been a persistent problem for the...Bachelet Administration. The Mapuche are Chile’s largest indigenous group and comprise approximately 4% of the population or 660,000 of Chile’s 16.5

Chile: Political and Economic Conditions and U.S. Relations

DTIC Science & Technology

2009-01-12

Demonstrations ........................................................................................................ 5 Mapuche Activism...is the root problem.18 ’ # Confrontation with the Mapuche population has been a persistent problem for the Bachelet Administration...The Mapuche are Chile’s largest indigenous group and comprise approximately 4% of the population or 660,000 of Chile’s 16.5 million citizens.19 They

From primary care to public health: using Problem-based Learning and the ecological model to teach public health to first year medical students.

PubMed

Hoover, Cora R; Wong, Candice C; Azzam, Amin

2012-06-01

We investigated whether a public health-oriented Problem-Based Learning case presented to first-year medical students conveyed 12 "Population Health Competencies for Medical Students," as recommended by the Association of American Medical Colleges and the Regional Medicine-Public Health Education Centers. A public health-oriented Problem-Based Learning case guided by the ecological model paradigm was developed and implemented among two groups of 8 students at the University of California, Berkeley-UCSF Joint Medical Program, in the Fall of 2010. Using directed content analysis, student-generated written reports were coded for the presence of the 12 population health content areas. Students generated a total of 29 reports, of which 20 (69%) contained information relevant to at least one of the 12 population health competencies. Each of the 12 content areas was addressed by at least one report. As physicians-in-training prepare to confront the challenges of integrating prevention and population health with clinical practice, Problem-Based Learning is a promising tool to enhance medical students' engagement with public health.

Fast half-sibling population reconstruction: theory and algorithms.

PubMed

Dexter, Daniel; Brown, Daniel G

2013-07-12

Kinship inference is the task of identifying genealogically related individuals. Kinship information is important for determining mating structures, notably in endangered populations. Although many solutions exist for reconstructing full sibling relationships, few exist for half-siblings. We consider the problem of determining whether a proposed half-sibling population reconstruction is valid under Mendelian inheritance assumptions. We show that this problem is NP-complete and provide a 0/1 integer program that identifies the minimum number of individuals that must be removed from a population in order for the reconstruction to become valid. We also present SibJoin, a heuristic-based clustering approach based on Mendelian genetics, which is strikingly fast. The software is available at http://github.com/ddexter/SibJoin.git+. Our SibJoin algorithm is reasonably accurate and thousands of times faster than existing algorithms. The heuristic is used to infer a half-sibling structure for a population which was, until recently, too large to evaluate.

[Сhaotic dynamics of cardio-intervals in three age groups of indigenous and non-indigenous population of Ugra].

PubMed

Eskov, V M; Khadartsev, A A; Eskov, V V; Vokhmina, J V

2016-01-01

The problem of life expectancy of indigenous and non-indigenous population of northern territories of the Russian Federation is considered in terms of economic growth and industrial development of the northern territories. The importance of prolonging the period of active working age of non-indigenous population of Khanty-Mansi Autonomous Okrug-Ugra and Yamalo-Nenets Autonomous Okrug is increasing. Four directions for possible prolongation of the active life of non-indigenous population were presented. The problem of comparative dynamics of age-related changes of cardiovascular system on three specific age groups of female indigenous and non-indigenous population is being considered. A decrease in volume of quasi-attractors in the phase space of states is equivalent to strengthening of physical activity, which is typical of normal aging. It is proposed to use the mathematical pattern to reduce these volumes in assessing the dynamics of human aging in the North.

Steady states and outbreaks of two-phase nonlinear age-structured model of population dynamics with discrete time delay.

PubMed

Akimenko, Vitalii; Anguelov, Roumen

2017-12-01

In this paper we study the nonlinear age-structured model of a polycyclic two-phase population dynamics including delayed effect of population density growth on the mortality. Both phases are modelled as a system of initial boundary values problem for semi-linear transport equation with delay and initial problem for nonlinear delay ODE. The obtained system is studied both theoretically and numerically. Three different regimes of population dynamics for asymptotically stable states of autonomous systems are obtained in numerical experiments for the different initial values of population density. The quasi-periodical travelling wave solutions are studied numerically for the autonomous system with the different values of time delays and for the system with oscillating death rate and birth modulus. In both cases it is observed three types of travelling wave solutions: harmonic oscillations, pulse sequence and single pulse.

Demographics and diaspora, gender and genealogy: anthropological notes on Greek population policy.

PubMed

Paxson, H

1997-01-01

Since World War II, Greece's birth rate has fallen into a worsening decline. With the steady emigration of Greeks throughout the century to North America, Australia, and Germany, Greece has experienced one of the most rapid population declines in Europe. In 1991, the PASOK government convened a special Parliamentary Commission to study the demographic problem and develop recommendations for its resolution. Released in 1993, and comparing Greece's depressed population growth rates with the markedly higher ones of Albania and Turkey, the report argues that the demographic problem is one of national survival because a decline in the population undermines the territorial integrity and national independence of the country. At least half of all pregnancies in Greece end in abortion, and the report attributes 40% of the declining population growth rate to women who have repeat abortions. To confront the population dilemma, Greek officials are downplaying the diaspora and encouraging women at home to produce more babies. Maternal pensions forwarded by the state as family and population policies are being criticized by Athenian women as a means of professionalizing motherhood and perpetuating a limited vision of female adulthood. The author explores why the declining birth rate is considered to be such a problem in Greece, even though the other countries of Europe are also experiencing birth rate declines; why and how women are blamed for the demographic situation; and why the state, despite its vehement rhetoric, has failed to implement a family policy capable of boosting fertility.

Election '94: a population overview.

PubMed

Dixon, B

1994-01-01

President Bill Clinton has been more outspoken and active than previous presidents in negotiations leading to the 1994 International Conference on Population and Development. He has put population stabilization at the top of the overall foreign policy agenda, sending to Congress a bill designed to make sustainable development and population stabilization cornerstones of US foreign policy. Moreover, the administration's commitment to solving the population problem is reflected in each of the two budgets submitted to Congress with increased funds requested and received for international family planning and the UN Population Fund. The US now leads the search for new solutions to the problem of rapid population growth. The right-wing conservatism and ignorance of the Reagan-Bush years, however, threatens to return following the November 1994 national elections. Historically, the party which controls the White House loses Congressional seats during mid-term elections. If the Democrats lose up to fifteen seats, the shift will be an historical norm. A Democratic loss of 25 or more seats, however, may pose a serious problem for Clinton. Domestic and international family planning, sex education, health care, abortion, and environmental protection all hang in the balance. During this period of increased partisanship, 36 of the 44 Republicans in the Senate supported a Helms amendment to limit US participation in the Cairo conference. Republican control of the Senate would likely keep the US from carrying out the commitments made at the conference on family planning, women's health coverage, and environmental protection.

Health-Related Quality of Life of the General German Population in 2015: Results from the EQ-5D-5L.

PubMed

Huber, Manuel B; Felix, Julia; Vogelmann, Martin; Leidl, Reiner

2017-04-16

The EQ-5D-5L is a widely used generic instrument to measure health-related quality of life. This study evaluates health perception in a representative sample of the general German population from 2015. To compare results over time, a component analysis technique was used that separates changes in the description and valuation of health states. The whole sample and also subgroups, stratified by sociodemographic parameters as well as disease affliction, were analyzed. In total, 2040 questionnaires (48.4% male, mean age 47.3 year) were included. The dimension with the lowest number of reported problems was self-care (93.0% without problems), and the dimension with the highest proportion of impairment was pain/discomfort (71.2% without problems). Some 64.3% of the study population were identified as problem-free. The visual analog scale (VAS) mean for all participants was 85.1. Low education was connected with significantly lower VAS scores, but the effect was small. Depression, heart disease, and diabetes had a strong significant negative effect on reported VAS means. Results were slightly better than those in a similar 2012 survey; the most important driver was the increase in the share of the study population that reported to be problem-free. In international comparisons, health perception of the general German population is relatively high and, compared with previous German studies, fairly stable over recent years. Elderly and sick people continue to report significant reductions in perceived health states.

[The key problems in the population exposure assessment of hazardous chemicals accidents].

PubMed

Pan, L J; Liu, F P; Zhang, X; Bai, X T; Shi, X M

2016-07-06

Serious accidents of hazardous chemicals can cause a variety of acute or chronic impairment in human health. The effects of hazardous chemicals on human health can be identified by carrying on population exposure assessment. Through analyzing the domestic and overseas population exposure assessment cases related to hazardous chemicals accidents, we summarized that the base and key of the population exposure assessment were to identify the characteristics of the chemicals , delimit the area and the population exposed to the chemicals, and collect the data of the monitored chemicals and the population health in the polluted area.

Accounting for connectivity and spatial correlation in the optimal placement of wildlife habitat

Treesearch

John Hof; Curtis H. Flather

1996-01-01

This paper investigates optimization approaches to simultaneously modelling habitat fragmentation and spatial correlation between patch populations. The problem is formulated with habitat connectivity affecting population means and variances, with spatial correlations accounted for in covariance calculations. Population with a pre-specifled confidence level is then...

China: Awakening Giant Developing Solutions to Population Aging

ERIC Educational Resources Information Center

Zhang, Ning Jackie; Guo, Man; Zheng, Xiaoying

2012-01-01

As the world's most populous country with the largest aging population and a rapidly growing economy, China is receiving increased attention from both the Chinese government and the governments of other countries that face low fertility and aging problems. This unprecedented shift of demographic structure has repercussions for many aspects of…

Population-Wide Parenting Intervention Training: Initial Feasibility

ERIC Educational Resources Information Center

Shapiro, Cheri J.; Prinz, Ronald J.; Sanders, Matthew R.

2008-01-01

A population-level approach to deliver parenting and family support is a necessary but neglected approach needed to reduce the high prevalence of emotional/behavioral problems in children, decrease inadequate and potentially abusive parenting practices, and to provide improved parenting support to all parents within a specified population. We…

Population Growth: Crisis and Challenge.

ERIC Educational Resources Information Center

Beaton, John R., Ed.; Doberenz, Alexander R., Ed.

The proceedings of this first annual symposium on population growth considers the consequences of this growth, along with possible means of regulation. Topics of speeches include: Population Outlook in Asia (Irene Taeuber); Malnutrition is a Problem of Ecology (Paul Gyorgy); The Leisure Explosion (E. H. Storey); Effects of Pollution on Population…

Population.

ERIC Educational Resources Information Center

International Planned Parenthood Federation, London (England).

In an effort to help meet the growing interest and concern about the problems created by the rapid growth of population, The International Planned Parenthood Federation has prepared this booklet with the aim of assisting the study of the history and future trends of population growth and its impact on individual and family welfare, national,…

Methods for assessing fish populations

Treesearch

Kevin L. Pope; Steve E. Lochmann; Michael K. Young

2010-01-01

Fisheries managers are likely to assess fish populations at some point during the fisheries management process. Managers that follow the fisheries management process (see Chapter 5) might find their knowledge base insufficient during the steps of problem identification or management action and must assess a population before appropriate actions can be taken. Managers...

Learning, Attention/Hyperactivity, and Conduct Problems as Sequelae of Excessive Daytime Sleepiness in a General Population Study of Young Children

PubMed Central

Calhoun, Susan L.; Fernandez-Mendoza, Julio; Vgontzas, Alexandros N.; Mayes, Susan D.; Tsaoussoglou, Marina; Rodriguez-Muñoz, Alfredo; Bixler, Edward O.

2012-01-01

Study Objectives: Although excessive daytime sleepiness (EDS) is a common problem in children, with estimates of 15%; few studies have investigated the sequelae of EDS in young children. We investigated the association of EDS with objective neurocognitive measures and parent reported learning, attention/hyperactivity, and conduct problems in a large general population sample of children. Design: Cross-sectional. Setting: Population based. Participants: 508 children from The Penn State Child Cohort. Interventions: N/A. Measurements and Results: Children underwent a 9-h polysomnogram, comprehensive neurocognitive testing, and parent rating scales. Children were divided into 2 groups: those with and without parent-reported EDS. Structural equation modeling was used to examine whether processing speed and working memory performance would mediate the relationship between EDS and learning, attention/hyperactivity, and conduct problems. Logistic regression models suggest that parent-reported learning, attention/hyperactivity, and conduct problems, as well as objective measurement of processing speed and working memory are significant sequelae of EDS, even when controlling for AHI and objective markers of sleep. Path analysis demonstrates that processing speed and working memory performance are strong mediators of the association of EDS with learning and attention/hyperactivity problems, while to a slightly lesser degree are mediators from EDS to conduct problems. Conclusions: This study suggests that in a large general population sample of young children, parent-reported EDS is associated with neurobehavioral (learning, attention/hyperactivity, conduct) problems and poorer performance in processing speed and working memory. Impairment due to EDS in daytime cognitive and behavioral functioning can have a significant impact on children's development. Citation: Calhoun SL; Fernandez-Mendoza J; Vgontzas AN; Mayes SD; Tsaoussoglou M; Rodriguez-Muñoz A; Bixler EO. Learning, attention/hyperactivity, and conduct problems as sequelae of excessive daytime sleepiness in a general population study of young children. SLEEP 2012;35(5):627-632. PMID:22547888

Slowed ageing, welfare, and population problems.

PubMed

Wareham, Christopher

2015-10-01

Biological studies have demonstrated that it is possible to slow the ageing process and extend lifespan in a wide variety of organisms, perhaps including humans. Making use of the findings of these studies, this article examines two problems concerning the effect of life extension on population size and welfare. The first--the problem of overpopulation--is that as a result of life extension too many people will co-exist at the same time, resulting in decreases in average welfare. The second--the problem of underpopulation--is that life extension will result in too few people existing across time, resulting in decreases in total welfare. I argue that overpopulation is highly unlikely to result from technologies that slow ageing. Moreover, I claim that the problem of underpopulation relies on claims about life extension that are false in the case of life extension by slowed ageing. The upshot of these arguments is that the population problems discussed provide scant reason to oppose life extension by slowed ageing.

Gaussian process-based Bayesian nonparametric inference of population size trajectories from gene genealogies.

PubMed

Palacios, Julia A; Minin, Vladimir N

2013-03-01

Changes in population size influence genetic diversity of the population and, as a result, leave a signature of these changes in individual genomes in the population. We are interested in the inverse problem of reconstructing past population dynamics from genomic data. We start with a standard framework based on the coalescent, a stochastic process that generates genealogies connecting randomly sampled individuals from the population of interest. These genealogies serve as a glue between the population demographic history and genomic sequences. It turns out that only the times of genealogical lineage coalescences contain information about population size dynamics. Viewing these coalescent times as a point process, estimating population size trajectories is equivalent to estimating a conditional intensity of this point process. Therefore, our inverse problem is similar to estimating an inhomogeneous Poisson process intensity function. We demonstrate how recent advances in Gaussian process-based nonparametric inference for Poisson processes can be extended to Bayesian nonparametric estimation of population size dynamics under the coalescent. We compare our Gaussian process (GP) approach to one of the state-of-the-art Gaussian Markov random field (GMRF) methods for estimating population trajectories. Using simulated data, we demonstrate that our method has better accuracy and precision. Next, we analyze two genealogies reconstructed from real sequences of hepatitis C and human Influenza A viruses. In both cases, we recover more believed aspects of the viral demographic histories than the GMRF approach. We also find that our GP method produces more reasonable uncertainty estimates than the GMRF method. Copyright © 2013, The International Biometric Society.

[Population planning unit is developed in the Congo].

PubMed

Amouali, C; Poukouta, P

1989-01-01

This article is an update on the demographic situation in the Congo and the institutionalization of a population unit in The Ministry of Plan. From 1974-84 the population increased 44.9% going from 1,319,790 to 1,912,429 at a growth rate of 3.48% and possibly doubling in 20 years (2005). However, the major transformation has been the growth of the urban areas over the rural. From 1974-84 the rural population went from 819,430 to 934,849 while the urban population went from 500,360 in 1974 to 977,580 in 1984. The growth rate of the rural areas was 1.22% while that for the urban was 6.38% Infant mortality rate stands at 73/1000; life expectancy is 46.9 for men and 50.0 for women. The average fertility rate is 6. This demographic situation with the inherent problems of the rapidly growing urbanization of the 2 principal cities, Brazzaville and Pointe-Noire, has led to problems in health services and high morbidity and mortality rates. The Government has created 3 national organizations to coordinate population activities in the country: 1) The National Council on Population, (1988) an interministerial council, presided over by the Prime Minister, that defines and formulates national population policies as integral components to the country's socioeconomic development plans; 2) The National Commission on Population (CONAPO), headed by the Minister of Plan, Finance and Economics as the administrative organ of The National Council on Population, and responsible for the technical and evaluation activities of The National Council on Population; and 3) The Population Planning Unit headed by the Director of Human Resources in the Ministry of Plan responsible for identifying, formulating and evaluating population policies in the Congo. These institutions were created as a result of the 1974 Bucharest Conference and the 1984 Arusha Conference were population and development were considered integral components, and of results of 2 censuses and population surveys highlighting the demographic situation in the Congo.

Approaches of researches in medical geography in Poland and Ukraine

NASA Astrophysics Data System (ADS)

Pantylej, Wiktoria

2008-01-01

This paper deals with the historical review of medical geography in the world, in Poland and in Ukraine. There are different approaches in medical geography: according to the research subject (ecological and economic approaches) and according to the current affairs of research (approach concerns sexuality, the age of the population and accordingly, accessibility of health care services to the population). To the author's mind, the most perspective approaches in medical geography in Poland and Ukraine are as follows: - integrative - dedicated to the health status of the population in connection with the quality and life level; - mathematical-statistical - connected with the problem of synthetic indexes of health status of the populations and factors influencing it, and with the problem of economic value of health and life of the population; - social-economic - the analysis of the influence of socioeconomic factors (such as wealth measure, rate of unemployment, work conditions and others) on public health; - ecological - connected with the researches dedicated to the analysis of environmental impact on public health status of the population; - demographical - the analysis of demographical factors of forming public health status; - social-psychological - health culture of the population, perception of the own health/morbidity and health care systems existing in different countries.

Osteoarthritis and other long-term health conditions in former elite cricketers.

PubMed

Jones, Mary E; Davies, Madeleine A M; Leyland, Kirsten M; Delmestri, Antonella; Porter, Angus; Ratcliffe, Jason; Peirce, Nick; Newton, Julia L; Arden, Nigel K

2018-06-01

This study aimed to describe the prevalence and risk of chronic conditions in former elite cricketers compared to a normal population, and describe wellbeing in former elite cricketers. Cross-sectional study. Former elite cricketers, recruited from the Professional Cricketers' Association, completed a self-report cross-sectional questionnaire. The English Longitudinal Study of Ageing (ELSA) served as the normal population. The prevalence of self-reported, GP-diagnosed conditions (heart problems, hypertension, stroke, diabetes, asthma, dementia, osteoarthritis (OA), total hip replacement (THR), total knee replacement (TKR), anxiety, depression) were reported for both population samples. Standardised morbidity ratios (SMRs) compared chronic conditions in sex-, age- and BMI-matched former cricketers (n=113) and normal population (n=4496). Heart problems were reported by 13.3% of former cricketers, significantly lower than the normal population, SMR 0.55 (0.33-0.91). Former cricketers reported 31.9% hypertension, 1.8% stroke, 6.2% diabetes, 15.0% asthma, and no dementia, none significantly different to the normal population. OA, THR, and TKR were reported by 51.3%, 14.7% and 10.7% of former cricketers, respectively, significantly higher than the normal population, SMRs 3.64 (2.81-4.71), 3.99 (2.21-7.20) and 3.84 (1.92-7.68). Anxiety and depression were reported by 12.4% and 8.8% of former cricketers, respectively, SMRs 3.95 (2.34-6.67) and 2.22 (1.20-4.14). 97% of former cricketers reflected they would undertake their cricket career again, 98% agreed that cricket enriched their lives. Heart problems were significantly lower, while OA, THR, TKR, anxiety, and depression were significantly higher in the former cricketers compared to the normal population (ELSA). Most former cricketers reflected positively on their career. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Reproductive health, population growth, economic development and environmental change.

PubMed

Lincoln, D W

1993-01-01

World population will increase by 1000 million, or by 20%, within 10 years. Ninety-five per cent of this increase will occur in the South, in areas that are already economically, environmentally and politically fragile. Morbidity and mortality associated with reproduction will be greater in the current decade than in any period in human history. Annually, 40-60 million pregnancies will be terminated and 5-10 million children will die within one year of birth. AIDS-related infections, e.g. tuberculosis, will undermine health care in Africa (and elsewhere) and in places AIDS-related deaths will decimate the work-force. The growth in population and associated morbidity will inhibit global economic development and spawn new problems. The key issues are migration, the spread of disease, the supply of water and the degradation of land, and fiscal policies with respect to family planning, pharmaceuticals and Third-World debt. Full education, particularly of women, and more effective family planning in the South have the power to unlock the problem. Failure will see the developed countries, with their 800 million population, swamped by the health, economic and environmental problems of the South, with its projected population of 5400 million people for the year 2000.

Marginalization and health service coverage among indigenous, rural, and urban populations: a public health problem in Mexico.

PubMed

Roldán, José; Álvarez, Marsela; Carrasco, María; Guarneros, Noé; Ledesma, José; Cuchillo-Hilario, Mario; Chávez, Adolfo

2017-12-01

  Marginalization is a significant issue in Mexico, involving a lack of access to health services with differential impacts on Indigenous, rural and urban populations. The objective of this study was to understand Mexico’s public health problem across three population areas, Indigenous, rural and urban, in relation to degree of marginalization and health service coverage.   The sampling universe of the study consisted of 107 458 geographic locations in the country. The study was retrospective, comparative and confirmatory. The study applied analysis of variance, parametric and non-parametric, correlation and correspondence analyses.   Significant differences were identified between the Indigenous, rural and urban populations with respect to their level of marginalization and access to health services. The most affected area was Indigenous, followed by rural areas. The sector that was least affected was urban.   Although health coverage is highly concentrated in urban areas in Mexico, shortages are mostly concentrated in rural areas where Indigenous groups represent the extreme end of marginalization and access to medical coverage. Inadequate access to health services in the Indigenous and rural populations throws the gravity of the public health problem into relief.

New light on old problem: population.

PubMed

Padilla, T

1982-01-01

A central issue of the Third Asian and Pacific Population Conference, to be held in Sri Lanka in September 1982, is the need for full recognition on the part of developing countries that an integrated approach to population and development is essential. Such an approach requires the following: management of internal migration and urbanization; women's participation in development; and increased involvement in promoting family planning, family welfare, and family health programs. Of much concern is the fact that the ESCAP region's urban population is projected to grow from 660 million in 1980 to 1347 million by the year 2000. Much of this increase will occur in the largest cities. Unplanned urbanization and a growing population reservoir in rural areas will continue to spur movements to the cities, aggravating the urban malaise, yet migration is young people's only option if rural populations are to survive. These problems plague most governments. A recent conference held in Rome urged governments to formulate comprehensive population policies and programs, to specify goals on the rate of population growth and on the distribution of population between urban and rural areas, and to plan for the redistribution of population. The conference also recommended that cities pay attention to problems of the shantytown and slum dwellers who are principally rural migrants and the urban poor. In addition the region's corps of development planners and experts worry about the staggering increase in migration by 3rd world guest workers to the high income OPEC members in the Middle East and the industrialized market economy nations. The proper management of international migration should increase the reabsorptive capacity of sending countries to ensure the reintegration of returning off-loaded guest workers and should try to prevent the rural stagnation due to large scale migration by the young and the better educated from the countryside. Internal and international migration give women an opportunity to discover their great development potential. Yet, more generally, women breaking out of social structures that foster dependency and exploitation are in need of more than simple, single factor solutions. Emerging relationships between declining mortality levels and women's participation in development and economic activities will be explored at the Third Asian and Pacific Population Conference.

Children's Problems Predict Adults' "DSM-IV" Disorders across 24 Years

ERIC Educational Resources Information Center

Reef, Joni; van Meurs, Inge; Verhulst, Frank C.; van der Ende, Jan

2010-01-01

Objective: The goal of this study was to determine continuities of a broad range of psychopathology from childhood into middle adulthood in a general population sample across a 24-year follow-up. Method: In 1983, parent ratings of children's problems were collected with the Child Behavior Checklist (CBCL) in a general population sample of 2,076…

Changing Populations, Changing Schools. Ninety-fourth Yearbook of the National Society for the Study of Education. Part II.

ERIC Educational Resources Information Center

Flaxman, Erwin, Ed.; Passow, A. Harry, Ed.

1995-01-01

The contributors to this yearbook attempt to explain the reasons for the poor fit between schools and poor, immigrant, linguistically different, and racial minority students. The problems that confront schools because of changing populations and increased diversity are discussed in the following chapters: (1) "The Old Problem of 'New…

Increased Risk for Substance Use-Related Problems in Autism Spectrum Disorders: A Population-Based Cohort Study

ERIC Educational Resources Information Center

Butwicka, Agnieszka; Långström, Niklas; Larsson, Henrik; Lundström, Sebastian; Serlachius, Eva; Almqvist, Catarina; Frisén, Louise; Lichtenstein, Paul

2017-01-01

Despite limited and ambiguous empirical data, substance use-related problems have been assumed to be rare among patients with autism spectrum disorders (ASD). Using Swedish population-based registers we identified 26,986 individuals diagnosed with ASD during 1973-2009, and their 96,557 non-ASD relatives. ASD, without diagnosed comorbidity of…

Creative Problem Solving with Marginalized Populations: Reclaiming Lost Prizes through In-the-Trenches Interventions

ERIC Educational Resources Information Center

McCluskey, Ken W.; Baker, Philip A.; McCluskey, Andrea L. A.

2005-01-01

This article describes several initiatives in which Creative Problem Solving, in combination with career exploration and mentoring, has been used successfully to identify and develop the talents of "at-risk" populations. During the past decade, the Lost Prizes project helped turn around the lives of talented but troubled high-school…

An Address on the Population Problem: Address to the Massachusetts Institute of Technology.

ERIC Educational Resources Information Center

McNamara, Robert S.

In this speech, Robert McNamara examines the background of the world population problem, analyzes its current trends, evaluates the measures available to deal with it, and suggests actions governments and others can take to help solve it. It now appears that significant fertility decline may have begun in developing countries. Data seem to…

Population Control, Family Planning and Planned Parenthood.

ERIC Educational Resources Information Center

Hilmar, Norman A.

Remarks in this article were made as part of a panel discussion presented at the Planned Parenthood-World Population combined Southeast Council and National Board Meeting, Savannah, Georgia, in May 1970. The problems and consequences of an increasing birth rate are indicated along with the need for reducing present rates of population growth and…

The demography of the Arab Republic of Egypt: population issues and policies.

PubMed

Holmberg, I

1981-01-01

The author examines some aspects of population growth in Egypt. Recent trends in fertility, mortality, urbanization, industrialization, regional development, and internal migation are described. The demographic and socioeconomic consequences of rapid population growth are considered, and the possibility of formulating government policies to alleviate problems associated with rapid growth is discussed

Predictors of Quality of Life in Economically Disadvantaged Populations in Montreal

ERIC Educational Resources Information Center

Caron, Jean

2012-01-01

Most epidemiological studies agree that economically disadvantaged populations are the groups most vulnerable to mental health problems and report lower quality of life among these populations. However, it appears that access to social support plays a role in protecting against the chronic stress resulting from conditions such as poverty. This…

Population Biology, Conservation Biology, and the Future of Humanity.

ERIC Educational Resources Information Center

Ehrlich, Paul R.

1987-01-01

Recounts some of the progress that has been made in the field of population biology. Presents some of the important advances made in the field, along with some of their applications to societal problems. Calls for more cooperation between population scientists and social scientists, and more environmental education for the public. (TW)

Development and genetic characterization of an Advanced Backcross-Nested Association Mapping (AB-NAM) population of wild × cultivated barley

USDA-ARS?s Scientific Manuscript database

The ability to access alleles from unadapted germplasm collections is a long-standing problem for geneticists and breeders. Here we developed, characterized, and demonstrated the utility of a wild barley advanced backcross-nested association mapping (AB-NAM) population. We developed this population ...

Rural Health Care in Texas: The Facts--1984.

ERIC Educational Resources Information Center

Morrison, Nolan; And Others

The size of Texas and the distribution of its population result in service delivery, economic, educational, transportation, communication, and health problems. Texas is the second largest state in the nation, is third largest in population, has a population growing at a faster rate than the national average, and is a primarily rural state--20% of…

Catholic Perspectives on Population Issues. Population Bulletin, Vol. 35, No. 6.

ERIC Educational Resources Information Center

Murphy, Francis X.

The bulletin investigates the major positions held by the Catholic Church toward population problems. Separate sections discuss the demographic debate, traditional church teaching, the birth control movement, the Vatican Council II and the Papal Birth Control Commission, Pope Paul's 1968 Encyclical against contraception, the 1980 Synod of Bishops,…

Rapid Population Growth-Cause or Result of Global Problems?

ERIC Educational Resources Information Center

Schwartz, Richard H.

Explosive population growth is a symptom of the world's unjust and inequitable social, political, and economic conditions. The current rate of growth is staggering, particularly in the cities of the underdeveloped countries. While some progress has been made in slowing population growth, several factors still contribute to its momentum. One of…

Pediatric and Adolescent Issues in Underserved Populations.

PubMed

Desai, Neerav; Romano, Mary Elizabeth

2017-03-01

Children and adolescents in underserved populations have health care risks that are different from those of the adult population. Providers need to be aware of these needs and the available resources. Providers should work with school and community organizations to provide timely and appropriate preventive health care and screen for medical and mental health problems that occur more commonly in these high-risk patient populations. Copyright © 2016 Elsevier Inc. All rights reserved.

Intellectual, behavioral, and emotional functioning in children with syndromic craniosynostosis.

PubMed

Maliepaard, Marianne; Mathijssen, Irene M J; Oosterlaan, Jaap; Okkerse, Jolanda M E

2014-06-01

To examine intellectual, behavioral, and emotional functioning of children who have syndromic craniosynostosis and to explore differences between diagnostic subgroups. A national sample of children who have syndromic craniosynostosis participated in this study. Intellectual, behavioral, and emotional outcomes were assessed by using standardized measures: Wechsler Intelligence Scale for Children, Third Edition, Child Behavior Checklist (CBCL)/6-18, Disruptive Behavior Disorder rating scale (DBD), and the National Institute of Mental Health Diagnostic Interview Schedule for Children. We included 82 children (39 boys) aged 6 to 13 years who have syndromic craniosynostosis. Mean Full-Scale IQ (FSIQ) was in the normal range (M = 96.6; SD = 21.6). However, children who have syndromic craniosynostosis had a 1.9 times higher risk for developing intellectual disability (FSIQ < 85) compared with the normative population (P < .001) and had more behavioral and emotional problems compared with the normative population, including higher scores on the CBCL/6-18, DBD Total Problems (P < .001), Internalizing (P < .01), social problems (P < .001), attention problems (P < .001), and the DBD Inattention (P < .001). Children who have Apert syndrome had lower FSIQs (M = 76.7; SD = 13.3) and children who have Muenke syndrome had more social problems (P < .01), attention problems (P < .05), and inattention problems (P < .01) than normative population and with other diagnostic subgroups. Although children who have syndromic craniosynostosis have FSIQs similar to the normative population, they are at increased risk for developing intellectual disability, internalizing, social, and attention problems. Higher levels of behavioral and emotional problems were related to lower levels of intellectual functioning.

Gambling behavior and problem gambling reflecting social transition and traumatic childhood events among Greenland Inuit: a cross-sectional study in a large indigenous population undergoing rapid change.

PubMed

Larsen, Christina Viskum Lytken; Curtis, Tine; Bjerregaard, Peter

2013-12-01

An increase in social pathologies is a key feature in indigenous populations undergoing transition. The Greenland Inuit are a large indigenous population constituting a majority in their own country, which makes it possible to investigate differences within the population. This led us to study gambling behavior and problem gambling among Greenland Inuit in relation to the ongoing social transition and traumatic events during childhood. A large representative cross-sectional study was conducted among Greenland Inuit (n = 2,189). Data was collected among adults (18+) in 9 towns and 13 villages in Greenland from 2005 to 2010. Problem gambling, gambling behavior and traumatic childhood events were measured through a self-administered questionnaire. The lie/bet screen was used to identify past year and lifetime problem gambling. Social transition was measured as place of residence and a combination of residence, education and occupation. The lifetime prevalence of problem gambling was 16 % among men and 10 % among women (p < 0.0001); and higher in towns (19 %) compared to the capital of Nuuk (11 %) and in villages (12 %) (men only, p = 0.020). Lifetime problem gambling was associated with social transition (p = 0.023), alcohol problems in childhood home (p = 0.001/p = 0.002) and sexual abuse in childhood (women only, p = 0.030). A comparably high prevalence of lifetime problem gambling among Greenland Inuit adds problem gambling to the list of social pathologies in Greenland. A significant association between lifetime problem gambling, social transition and traumatic childhood events suggests people caught between tradition and modern ways of life are more vulnerable to gambling problems.

Population, poverty and social transformation: an alternative paradigm.

PubMed

Pethe, V P

1992-06-01

"In this paper I have proposed a new alternative paradigm on the interrelations between population, poverty and the related concerns [in India]. Its central thesis is that the population problem has also the concomitant social problems [of] unemployment, ill health, [and] crime, [with] (1) poverty as their 'immediate' determinant, (2) such evils as inequality, consumerism, military expenditure, defective planning...as their 'intermediate' determinants, and (3) out-moded non-egalitarian social structures, vicious human psyche and spiritual degradation as their 'ultimate' determinants. This new paradigm has implications for policy and programme logistics that are fundamentally different from official policy." excerpt

The Methamphetamine Problem in the United States

PubMed Central

Gonzales, Rachel; Mooney, Larissa; Rawson, Richard

2015-01-01

Significant public health problems associated with methamphetamine (MA) production and use in the United States have emerged over the past 25 years. Although the popular press (Newsweek, Aug 8, 2008), has called MA “America’s Most Dangerous Drug” there has been considerable controversy about the size of the problem. Epidemiological indicators have given a mixed picture. National surveys of the adult U.S. population and school-based populations have consistently been used to support the position that MA use is a relatively minor concern (NSDUH, 2006; Johnston & O’Malley, 2007). However, many other data sources, including law-enforcement groups, welfare agencies, substance abuse treatment program admission data, data on criminal justice populations, and state/county executives indicate that MA is a very significant public health problem for many communities throughout much of the country (NDIC, 2007b; NACO, 2005, 2006; NIDA CEWG, 2007). In this article, we describe (1) the historical underpinnings of the MA problem, (2) trends in the epidemiological nature of the MA problem, (3) key subgroups at risk for MA problems, (4) the health and social factors associated with MA use, (5) interventions available for addressing the MA problem, and (5) lessons learned related to the MA problem. PMID:20070191

Identification of the population density of a species model with nonlocal diffusion and nonlinear reaction

NASA Astrophysics Data System (ADS)

Tuan, Nguyen Huy; Van Au, Vo; Khoa, Vo Anh; Lesnic, Daniel

2017-05-01

The identification of the population density of a logistic equation backwards in time associated with nonlocal diffusion and nonlinear reaction, motivated by biology and ecology fields, is investigated. The diffusion depends on an integral average of the population density whilst the reaction term is a global or local Lipschitz function of the population density. After discussing the ill-posedness of the problem, we apply the quasi-reversibility method to construct stable approximation problems. It is shown that the regularized solutions stemming from such method not only depend continuously on the final data, but also strongly converge to the exact solution in L 2-norm. New error estimates together with stability results are obtained. Furthermore, numerical examples are provided to illustrate the theoretical results.

Are mental health problems associated with use of Accident and Emergency and health-related harm?

PubMed

Keene, J; Rodriguez, J

2007-08-01

Previous findings indicate that mental health problems are common in Emergency departments; however, there are few studies of the extent of health-related problems and emergency service use in mental health populations as a whole. Record linkage methods were used to map the association between mental health, age, gender, and health-related harm across total health and mental health care populations in one geographical area, over three years. By examining patterns of health-related harm, an accurate profile of mentally ill Emergency patients was generated enabling identification of factors that increased vulnerability to harm. Of the total population of 625 964 individuals, 10.7% contacted Accident and Emergency (A&E) over three years, this proportion rose to 28.6% among the total secondary care mental health population. Young men and older women were more likely to contact A&E, both overall and within mental health populations and were also more likely to be frequent attendees at A&E. Four distinct groups (typologies) of mental health patients attending A&E emerged: young, male frequent attendees with self-inflicted and other traumatic injuries; young females also presenting with self-harm; older patients with multiple medical conditions; and very old patients with cardiac conditions and fractures. The study indicates increased A+E service use and unmet health-related need within a total mental health population. It identifies specific 'care populations' particularly vulnerable to accidents and self-harm and highlights the need for targeted services for mentally ill groups who may not access traditional health and social care services effectively.

[China's population policies: attempting to "resolve the wrong problem"?].

PubMed

Ratcliffe, J W

1989-03-01

This work argues that international efforts to resolve the population problem have failed primarily because they have been based on misconceptions concerning the definition of the problem and the relationship between population growth and development. The demographic experience of the People's Republic of China since the Revolution is used to illustrate these commonly shared misconceptions. The difficulty of defining the population problem results from differing interpretations of the basic fact that poor population groups tend to have higher fertility rates and faster growth than wealthier population groups. The Western industrial nations maintain that peoples or countries are poor because they have many children; the solution to the problem would require that they be provided access to modern contraception and associated services such as population and family planning education. Many Third World countries argue on the other hand that people have many children because they are poor, a view implying that greater social and economic development will provide the solution. The disagreement as to whether rapid population growth is a cause or a consequence of underdevelopment results in part from viewing overpopulation and underdevelopment as separate and distinct problems. Results of several carefully conducted evaluation studies have demonstrated that very little of the world fertility decline in the late 1960s and early 1970s was attributable to national family planning programs. Research has shown that equitable division of national wealth, education--especially of women, some employment factors such as a lack of opportunities for children, and a reliable social security system are the most powerful determinants of fertility. The studies indicate that fertility declines are induced by models of development that stress widespread social progress rather than provision of contraceptives and associated services. Examination of the Chinese demographic experience suggests that it falls into 5 clearly identifiable stages, beginning with high mortality and even higher fertility until 1957, the Great Leap Forward and its aftermath, the demographic transition from 1969 to 1979, and the stage of renewed growth from 1980 to the present. China has followed 3 radically different development models since 1957. Its experience demonstrates that development policies that result directly in generalized improvements in social conditions in areas such as nutrition, education, employment, and social security are the fundamental determinants of fertility decline. Chinese experience also suggests that when development policies are modified to stress national economic growth at the expense of social improvements, the need for children is also stimulated.

On Reverse Stackelberg Game and Optimal Mean Field Control for a Large Population of Thermostatically Controlled Loads

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

Li, Sen; Zhang, Wei; Lian, Jianming

This paper studies a multi-stage pricing problem for a large population of thermostatically controlled loads. The problem is formulated as a reverse Stackelberg game that involves a mean field game in the hierarchy of decision making. In particular, in the higher level, a coordinator needs to design a pricing function to motivate individual agents to maximize the social welfare. In the lower level, the individual utility maximization problem of each agent forms a mean field game coupled through the pricing function that depends on the average of the population control/state. We derive the solution to the reverse Stackelberg game bymore » connecting it to a team problem and the competitive equilibrium, and we show that this solution corresponds to the optimal mean field control that maximizes the social welfare. Realistic simulations are presented to validate the proposed methods.« less

[World population growth and the food supply].

PubMed

Huang, Y

1982-07-29

The general trend in the last several hundred years has been that the speed of growth in the food supply exceeds the speed of the population growth. For the time being, 2 major problems still exist. The 1st problem is that food production is still influenced by natural conditions. For example, abnormal weather conditions may cause regional food shortages. The 2nd problem is the imbalance of food consumption by the world population. This phenomenon exists between different social classes as well as between developed and developing countries. According to statistics released by the World Bank, 1 billion suffer from malnutrition today and most of them are in developing countries. In developed countries, about half of their increase in the food supply is for feed grains, and those countries follow the policy of reducing farm land for the purpose of maintaing stabl e grain prices. Up to the present time, grain prices have been unstable, and this has become a rather heavy economic burden for numerous developing countries. Many developing countries are trying to increase grain production by increasing their arable land and promoting their cultivating techniques. However, these countries are facing the problems of finding and adequate water supply, fertilizer, and pesticides. In addition, a rapid population growth in these countries has offset their endeavors in agriculture. In recent years, these counties have realized the necessity of birth control. The world population growth rate has decreased from 2% to about 1.7% in 1981. Birth control and an increase in the food supply will bring new hope to the world's problems of overpopulation and food supply.

A modified Wright-Fisher model that incorporates Ne: A variant of the standard model with increased biological realism and reduced computational complexity.

PubMed

Zhao, Lei; Gossmann, Toni I; Waxman, David

2016-03-21

The Wright-Fisher model is an important model in evolutionary biology and population genetics. It has been applied in numerous analyses of finite populations with discrete generations. It is recognised that real populations can behave, in some key aspects, as though their size that is not the census size, N, but rather a smaller size, namely the effective population size, Ne. However, in the Wright-Fisher model, there is no distinction between the effective and census population sizes. Equivalently, we can say that in this model, Ne coincides with N. The Wright-Fisher model therefore lacks an important aspect of biological realism. Here, we present a method that allows Ne to be directly incorporated into the Wright-Fisher model. The modified model involves matrices whose size is determined by Ne. Thus apart from increased biological realism, the modified model also has reduced computational complexity, particularly so when Ne⪡N. For complex problems, it may be hard or impossible to numerically analyse the most commonly-used approximation of the Wright-Fisher model that incorporates Ne, namely the diffusion approximation. An alternative approach is simulation. However, the simulations need to be sufficiently detailed that they yield an effective size that is different to the census size. Simulations may also be time consuming and have attendant statistical errors. The method presented in this work may then be the only alternative to simulations, when Ne differs from N. We illustrate the straightforward application of the method to some problems involving allele fixation and the determination of the equilibrium site frequency spectrum. We then apply the method to the problem of fixation when three alleles are segregating in a population. This latter problem is significantly more complex than a two allele problem and since the diffusion equation cannot be numerically solved, the only other way Ne can be incorporated into the analysis is by simulation. We have achieved good accuracy in all cases considered. In summary, the present work extends the realism and tractability of an important model of evolutionary biology and population genetics. Copyright © 2016 Elsevier Ltd. All rights reserved.

A fast least-squares algorithm for population inference

PubMed Central

2013-01-01

Background Population inference is an important problem in genetics used to remove population stratification in genome-wide association studies and to detect migration patterns or shared ancestry. An individual’s genotype can be modeled as a probabilistic function of ancestral population memberships, Q, and the allele frequencies in those populations, P. The parameters, P and Q, of this binomial likelihood model can be inferred using slow sampling methods such as Markov Chain Monte Carlo methods or faster gradient based approaches such as sequential quadratic programming. This paper proposes a least-squares simplification of the binomial likelihood model motivated by a Euclidean interpretation of the genotype feature space. This results in a faster algorithm that easily incorporates the degree of admixture within the sample of individuals and improves estimates without requiring trial-and-error tuning. Results We show that the expected value of the least-squares solution across all possible genotype datasets is equal to the true solution when part of the problem has been solved, and that the variance of the solution approaches zero as its size increases. The Least-squares algorithm performs nearly as well as Admixture for these theoretical scenarios. We compare least-squares, Admixture, and FRAPPE for a variety of problem sizes and difficulties. For particularly hard problems with a large number of populations, small number of samples, or greater degree of admixture, least-squares performs better than the other methods. On simulated mixtures of real population allele frequencies from the HapMap project, Admixture estimates sparsely mixed individuals better than Least-squares. The least-squares approach, however, performs within 1.5% of the Admixture error. On individual genotypes from the HapMap project, Admixture and least-squares perform qualitatively similarly and within 1.2% of each other. Significantly, the least-squares approach nearly always converges 1.5- to 6-times faster. Conclusions The computational advantage of the least-squares approach along with its good estimation performance warrants further research, especially for very large datasets. As problem sizes increase, the difference in estimation performance between all algorithms decreases. In addition, when prior information is known, the least-squares approach easily incorporates the expected degree of admixture to improve the estimate. PMID:23343408

A fast least-squares algorithm for population inference.

PubMed

Parry, R Mitchell; Wang, May D

2013-01-23

Population inference is an important problem in genetics used to remove population stratification in genome-wide association studies and to detect migration patterns or shared ancestry. An individual's genotype can be modeled as a probabilistic function of ancestral population memberships, Q, and the allele frequencies in those populations, P. The parameters, P and Q, of this binomial likelihood model can be inferred using slow sampling methods such as Markov Chain Monte Carlo methods or faster gradient based approaches such as sequential quadratic programming. This paper proposes a least-squares simplification of the binomial likelihood model motivated by a Euclidean interpretation of the genotype feature space. This results in a faster algorithm that easily incorporates the degree of admixture within the sample of individuals and improves estimates without requiring trial-and-error tuning. We show that the expected value of the least-squares solution across all possible genotype datasets is equal to the true solution when part of the problem has been solved, and that the variance of the solution approaches zero as its size increases. The Least-squares algorithm performs nearly as well as Admixture for these theoretical scenarios. We compare least-squares, Admixture, and FRAPPE for a variety of problem sizes and difficulties. For particularly hard problems with a large number of populations, small number of samples, or greater degree of admixture, least-squares performs better than the other methods. On simulated mixtures of real population allele frequencies from the HapMap project, Admixture estimates sparsely mixed individuals better than Least-squares. The least-squares approach, however, performs within 1.5% of the Admixture error. On individual genotypes from the HapMap project, Admixture and least-squares perform qualitatively similarly and within 1.2% of each other. Significantly, the least-squares approach nearly always converges 1.5- to 6-times faster. The computational advantage of the least-squares approach along with its good estimation performance warrants further research, especially for very large datasets. As problem sizes increase, the difference in estimation performance between all algorithms decreases. In addition, when prior information is known, the least-squares approach easily incorporates the expected degree of admixture to improve the estimate.

The population structure and recent colonization history of Oregon threespine stickleback determined using RAD-seq

PubMed Central

Catchen, Julian; Bassham, Susan; Wilson, Taylor; Currey, Mark; O’Brien, Conor; Yeates, Quick; Cresko, William A.

2013-01-01

Understanding how genetic variation is partitioned across genomes within and among populations is a fundamental problem in ecological and evolutionary genetics. To address this problem we are studied the threespine stickleback fish, which has repeatedly undergone parallel phenotypic and genetic differentiation when oceanic fish have invaded freshwater habitats. While significant evolutionary genetic research has been performed using stickleback from geographic regions that have been de-glaciated in the last 20,000 years, less research has focused on freshwater populations that predate the last glacial maximum. We performed RAD-seq based population genomic analyses on stickleback from across Oregon, which was not glaciated during the last maximum. We sampled stickleback from coastal, Willamette Basin, and central Oregon sites, analyzed their genetic diversity using RAD-seq, performed STRUCTURE analyses, reconstructed their phylogeographic history, and tested the hypothesis of recent stickleback introduction into central Oregon, where incidence of this species was only recently documented. Our results showed a clear phylogeographic break between coastal and inland populations, with oceanic populations exhibiting the lowest levels of divergence from one another. Willamette Basin and central Oregon populations formed a clade of closely related populations, a finding consistent with a recent introduction of stickleback into central Oregon. Finally, genome wide analysis of genetic diversity (π) and correlations of alleles within individuals in subpopulations (FIS) supported a role for introgressive hybridization in coastal populations and a recent expansion in central Oregon. Our results exhibit the power of next generation sequencing genomic approaches such as RAD-seq to identify both historical population structure and recent colonization history. PMID:23718143

Rare events in stochastic populations under bursty reproduction

NASA Astrophysics Data System (ADS)

Be'er, Shay; Assaf, Michael

2016-11-01

Recently, a first step was made by the authors towards a systematic investigation of the effect of reaction-step-size noise—uncertainty in the step size of the reaction—on the dynamics of stochastic populations. This was done by investigating the effect of bursty influx on the switching dynamics of stochastic populations. Here we extend this formalism to account for bursty reproduction processes, and improve the accuracy of the formalism to include subleading-order corrections. Bursty reproduction appears in various contexts, where notable examples include bursty viral production from infected cells, and reproduction of mammals involving varying number of offspring. The main question we quantitatively address is how bursty reproduction affects the overall fate of the population. We consider two complementary scenarios: population extinction and population survival; in the former a population gets extinct after maintaining a long-lived metastable state, whereas in the latter a population proliferates despite undergoing a deterministic drift towards extinction. In both models reproduction occurs in bursts, sampled from an arbitrary distribution. Using the WKB approach, we show in the extinction problem that bursty reproduction broadens the quasi-stationary distribution of population sizes in the metastable state, which results in a drastic reduction of the mean time to extinction compared to the non-bursty case. In the survival problem, it is shown that bursty reproduction drastically increases the survival probability of the population. Close to the bifurcation limit our analytical results simplify considerably and are shown to depend solely on the mean and variance of the burst-size distribution. Our formalism is demonstrated on several realistic distributions which all compare well with numerical Monte-Carlo simulations.

Technology: The Problem or the Solution to Childhood Obesity

ERIC Educational Resources Information Center

Silverstone, Susan; Teatum, Jim

2011-01-01

One-third of the population of US children is considered obese and two-thirds of the adult population falls into the same category. These figures have tripled over the last 30 years. This demonstrates that the existing strategies to combat obesity do not work and it is time to look for alternatives. The recommendation is to turn the problem into a…

Exploring the effects of population growth on future land use change in the Las Vegas Wash watershed: an integrated approach of geospatial modeling and analytics

EPA Science Inventory

The Las Vegas Valley metropolitan area is one of the fastest growing areas in the southwestern United States. The rapid urbanization has led to many environmental problems. For instance, as population growth and urbanization continue, there will be a problem with water shortage. ...

Body Mass Index in Adults with Intellectual Disability: Distribution, Associations and Service Implications--A Population-Based Prevalence Study

ERIC Educational Resources Information Center

Bhaumik, S.; Watson, J. M.; Thorp, C. F.; Tyrer, F.; McGrother, C. W.

2008-01-01

Background: Previous studies of weight problems in adults with intellectual disability (ID) have generally been small or selective and given conflicting results. The objectives of our large-scale study were to identify inequalities in weight problems between adults with ID and the general adult population, and to investigate factors associated…

Fetal growth and psychiatric and socioeconomic problems: population-based sibling comparison

PubMed Central

Class, Quetzal A.; Rickert, Martin E.; Larsson, Henrik; Lichtenstein, Paul; D’Onofrio, Brian M.

2014-01-01

Background It is unclear whether associations between fetal growth and psychiatric and socioeconomic problems are consistent with causal mechanisms. Aims To estimate the extent to which associations are a result of unmeasured confounding factors using a sibling-comparison approach. Method We predicted outcomes from continuously measured birth weight in a Swedish population cohort (n = 3 291 773), while controlling for measured and unmeasured confounding. Results In the population, lower birth weight (⩽2500 g) increased the risk of all outcomes. Sibling-comparison models indicated that lower birth weight independently predicted increased risk for autism spectrum disorder (hazard ratio for low birth weight = 2.44, 95% CI 1.99-2.97) and attention-deficit hyperactivity disorder. Although attenuated, associations remained for psychotic or bipolar disorder and educational problems. Associations with suicide attempt, substance use problems and social welfare receipt, however, were fully attenuated in sibling comparisons. Conclusions Results suggest that fetal growth, and factors that influence it, contribute to psychiatric and socioeconomic problems. PMID:25257067

Fetal growth and psychiatric and socioeconomic problems: population-based sibling comparison.

PubMed

Class, Quetzal A; Rickert, Martin E; Larsson, Henrik; Lichtenstein, Paul; D'Onofrio, Brian M

2014-11-01

It is unclear whether associations between fetal growth and psychiatric and socioeconomic problems are consistent with causal mechanisms. To estimate the extent to which associations are a result of unmeasured confounding factors using a sibling-comparison approach. We predicted outcomes from continuously measured birth weight in a Swedish population cohort (n = 3 291 773), while controlling for measured and unmeasured confounding. In the population, lower birth weight (⩽ 2500 g) increased the risk of all outcomes. Sibling-comparison models indicated that lower birth weight independently predicted increased risk for autism spectrum disorder (hazard ratio for low birth weight = 2.44, 95% CI 1.99-2.97) and attention-deficit hyperactivity disorder. Although attenuated, associations remained for psychotic or bipolar disorder and educational problems. Associations with suicide attempt, substance use problems and social welfare receipt, however, were fully attenuated in sibling comparisons. Results suggest that fetal growth, and factors that influence it, contribute to psychiatric and socioeconomic problems. Royal College of Psychiatrists.

[The Swiss population and drug problems: perception of the problems and proposals for solutions].

PubMed

Leuthold, A; Cattaneo, M; Dubois-Arber, F

1993-01-01

The aim of this study is to investigate which problems in relation with drug abuse are considered to be the most important by the Swiss population and which measures do they support to reduce them. Base for this study are the results of a representative telephone survey realized in october 1991 with 1004 Swiss residents. People are mostly concerned with problems related to the danger for youth and those concerning public order but also with the human condition of addicts. Drug addicts are considered as people who have lost the sense of live, as sick but also as dangerous and less truthful. Supported are overall prevention, offers for therapies, the repression of trafficking and money-laundering but not of drug users as well as measures going in the direction of harm-minimisation (shooting rooms, medical prescription of drugs). Younger people, those with higher education and the german-speaking population have a more positive view of drug addicts and support measures in the sense of harm-minimisation. Elder people and the french-speaking population have a rather negative view of drug addicts and don't favour measures for harm-minimisation.

Quality of life profile of general Vietnamese population using EQ-5D-5L.

PubMed

Nguyen, Long Hoang; Tran, Bach Xuan; Hoang Le, Quynh Ngoc; Tran, Tung Thanh; Latkin, Carl A

2017-10-11

Health-related quality of life (HRQOL) is a vital benchmark to assess the effects of health interventions and policies. Measuring HRQOL of the general population is essential to establish a reference for health outcomes evaluations. However, evidence on HRQOL of general populations in low and middle income countries is very limited. This study aimed to measure HRQOL of the Vietnamese population by using the EuroQol-5 dimensions-5 levels (EQ-5D-5L) instrument and determine its associated factors. A cross-sectional study was performed in Hanoi with 1571 residences in Hanoi, the capital city of Vietnam. EQ-5D-5L and EQ- visual analogue scale (EQ-VAS) were used to assess HRQOL. Potential covariates included socio-demographic characteristics, having acute symptoms in the last four weeks, chronic diseases in the last three months, having multiple health issues, and health service utilisation in the last twelve months. A generalized linear model was employed to identify the association between HRQOL and covariates. Overall, the mean EQ-5D utility index was 0.91 (SD = 0.15), and the mean EQ-VAS score was 87.4 (SD = 14.3). The highest proportion of respondents reporting any problems was in Usual activities (24.3%), followed by Anxiety/Depression (15.2%) and Pain/Discomfort (10.0%), while the lowest percentage was in Self-care (2.5%). Lower HRQOL composite scores were related to unemployment, lower income, higher education, living in urban areas, having chronic diseases, having multiple health issues and using health service. For any health problem self-reported by respondents, the health utility reduced by 0.02 (respiratory diseases) to 0.15 (musculoskeletal diseases). Health utility of the general population and reductions for self-reported health problems in this study are useful for future population health evaluations and comparisons. It also informs the development of interventions to reduce health problems of the general population.

REVIEWS OF TOPICAL PROBLEMS: Population synthesis in astrophysics

NASA Astrophysics Data System (ADS)

Popov, S. B.; Prokhorov, M. E.

2007-11-01

Population synthesis is a method for numerical simulation of the population of objects with a complex evolution. This method is widely used in astrophysics. We consider its main applications to studying astronomical objects. Examples of modeling evolution are given for populations of close binaries and isolated neutron stars. The application of the method to studying active galactic nuclei and the integral spectral characteristics of galaxies is briefly discussed. An extensive bibliography on all the topics covered is provided.

Symposium on Population and Human Rights.

PubMed

1981-06-01

The objectives of the Symposium on Population and Human Rights, held at the Vienna International Center during June 1981, included the following: to review the progress or lack thereof in the observance of human rights in the context of demographic, economic and social conditions and changes since the Amsterdam Symposium of 1974; to review leading population trends and policy changes since 1974 and also examine some possible implications of recent development in the field of medicine, biology, and genetic engineering; and to identify which conceptions of human rights relating to demographic phenomenon are appropriate for today's population problems and to formulate guidelines and standards suitable for these problems. The agenda for the Symposium, attended by about 27 distinguished jurists and demographers, covered the following items: human rights and population trends and policies; morbidity/mortality and human rights; fertility and human rights; internal migration and human rights; status of women, population, and human rights; and new institutional functions in the area of human rights and population. The following were among the main themes and recommendations of the Symposium: 1) the problems of human rights should be contextually handled in such a way as to take adequate account of prevailing socioeconomic and cultural conditions; 2) the realization of a positive right to individual and social development is often impeded, particularly in developing areas, by the prevalence of high mortality, malnutrition, and inadequate health services; 3) policies designed to influence fertility should, within the framework of general population policies, be part of the national strategy for general development; 4) the Symposium recognized the problems of monitoring and appraising the observance or violation of human rights as they relate to the rights of the individual to free movement and residence and the rights to work and decent living; 5) considering the significant changes in the form and character of international movements, it was noted that a significant gap exists between principles as enshrined in international instruments and the actual practice by governments; and 6) to improve the situation of women, it was deemed necessary to improve the knowledge base regarding their situation through more and better information and data and use of appropriate concepts and values.

Teacher's Guide in Population Education for Social Studies, Grades I-VI. Elementary Level. (Revised for Muslim Filipinos).

ERIC Educational Resources Information Center

Department of Education and Culture, Manila (Philippines).

Revised to be in accordance with the customs, traditions, beliefs, and practices of the Muslim Filipinos, these elementary-level social studies units will help Filipino children understand world population problems and develop the necessary skills, attitudes, and values that will lead them to make rational decisions about population matters,…

An NCME Instructional Module on Population Invariance in Linking and Equating

ERIC Educational Resources Information Center

Huggins, Anne C.; Penfield, Randall D.

2012-01-01

A goal for any linking or equating of two or more tests is that the linking function be invariant to the population used in conducting the linking or equating. Violations of population invariance in linking and equating jeopardize the fairness and validity of test scores, and pose particular problems for test-based accountability programs that…

The New Rural Society.

ERIC Educational Resources Information Center

Goldmark, Peter C.

The population explosion and the trend to urban-suburban living means that 80% of the nation's population lives on less than 10% of the land. A long-term solution to this problem calls for a total change in our population distribution as well as our life style--and the key to this plan lies in new applications for existing communication…

The potential impacts of the homeless on public lands

Treesearch

Sidney M. Blumner; Carolyn M. Daugherty

1995-01-01

The multidimensional problem of the homeless population in San Bernardino and nearby counties in California is examined and its impacts on adjacent public lands. The characteristics of the homeless in the area are described, as well as possible implications of this population for public lands use. Issues related to the homeless population are examined, such as...

The Church's Concern for Communities with a Rural Nonfarm Population in the Northeast U. S. A.

ERIC Educational Resources Information Center

Van Horn, George A., Ed.; And Others

A workshop was held in Gettysburg, Pennsylvania, to determine how the Lutheran Church might best serve the rural nonfarm population of the Northeast. Some of the topics discussed were: (1) the rural nonfarm family, (2) community development, and (3) serving a heterogeneous population. Attention was focused on psychological problems that can…

Psychopathology in a Swedish Population of School Children with Tic Disorders

ERIC Educational Resources Information Center

Khalifa, Najah; Von Knorring, Anne-Liis

2006-01-01

Objective: To examine patterns of psychiatric comorbid disorders and associated problems in a school population of children with tic disorders. Method: From a total population of 4,479 children, 25 with Tourette's disorder (TD), 34 with chronic motor tics (CMT), 24 with chronic vocal tics (CVT), and 214 with transient tics (TT) during the past…

A diffusion model of protected population on bilocal habitat with generalized resource

NASA Astrophysics Data System (ADS)

Vasilyev, Maxim D.; Trofimtsev, Yuri I.; Vasilyeva, Natalya V.

2017-11-01

A model of population distribution in a two-dimensional area divided by an ecological barrier, i.e. the boundaries of natural reserve, is considered. Distribution of the population is defined by diffusion, directed migrations and areal resource. The exchange of specimens occurs between two parts of the habitat. The mathematical model is presented in the form of a boundary value problem for a system of non-linear parabolic equations with variable parameters of diffusion and growth function. The splitting space variables, sweep method and simple iteration methods were used for the numerical solution of a system. A set of programs was coded in Python. Numerical simulation results for the two-dimensional unsteady non-linear problem are analyzed in detail. The influence of migration flow coefficients and functions of natural birth/death ratio on the distributions of population densities is investigated. The results of the research would allow to describe the conditions of the stable and sustainable existence of populations in bilocal habitat containing the protected and non-protected zones.

Convergence to a pulsating travelling wave for an epidemic reaction-diffusion system with non-diffusive susceptible population.

PubMed

Ducrot, Arnaud; Giletti, Thomas

2014-09-01

In this work we study the asymptotic behaviour of the Kermack-McKendrick reaction-diffusion system in a periodic environment with non-diffusive susceptible population. This problem was proposed by Kallen et al. as a model for the spatial spread for epidemics, where it can be reasonable to assume that the susceptible population is motionless. For arbitrary dimensional space we prove that large classes of solutions of such a system have an asymptotic spreading speed in large time, and that the infected population has some pulse-like asymptotic shape. The analysis of the one-dimensional problem is more developed, as we are able to uncover a much more accurate description of the profile of solutions. Indeed, we will see that, for some initially compactly supported infected population, the profile of the solution converges to some pulsating travelling wave with minimal speed, that is to some entire solution moving at a constant positive speed and whose profile's shape is periodic in time.

Population: fiction and fact.

PubMed

1979-09-01

This article was written to refute some common misunderstandings regarding worldwide population levels and worldwide nutrition levels. The world food supply is able to keep pace with high population growth levels. Worl food production currently meets world need; the problem is a distribution system which allocates food only to those who can pay rather than to those who need it. In many developing countries, the best agricultural lands are reserved for commercial crops rather than for subsistence crops. The U.S. food aid program does not help the most needy nations generally. The rate of world population growth is already slowing down. The desire for large families in developing countries is very often a realistic reaction to the prevailing economic system. Family planning programs will succeed. They will succeed even better in countries where general development planning is undertaken concurrently with family planning. Environmental problems are attributable to the consumption explosion in the rich countries rather than to the population explosion in the poor countries.

The interface between population and development models, plans and policies.

PubMed

Cohen, S I

1989-01-01

Scant attention has been given to integrating policy issues in population economics and development economics into more general frameworks. Reviewing the state of the art, this paper examines problems in incorporating population economics variables in development planning. Specifically, conceptual issues in defining population economics variables, modelling relationships between them, and operationalizing frameworks for decision making are explored with hopes of yielding tentative solutions. Several controversial policy issues affecting the development process are also examined in the closing section. 2 of these issues would be the social efficiency of interventions with fertility, and of resource allocations to human development. The effective combination between agriculture and industry in promoting and equitably distributing income growth among earning population groups is a 3rd issue of consideration. Finally, the paper looks at the optimal combination between transfer payments and provisions in kind in guaranteeing minimum consumption needs for poverty groups. Overall, the paper finds significant obstacles to refining the integration of population economics and development policy. Namely, integrating time and place dimensions in classifying people by activity, operationalizing population economics variable models to meet the practical situations of planning and programs, and assessing conflicts and complementarities between alternative policies pose problems. 2 scholarly comments follow the main body of the paper.

Gambling: Electronic friends or a threat to one's health and personal development?

PubMed Central

Svensson, Ove

2011-01-01

Gambling has become quite common in Sweden. The Swedish National Institute of Public Health (2010) has reported that about 70% of the Swedish population has gambled at least once during the last 12 months. Half of the population had gambled with money by 18 years of age and about 11% had gambled for the first time when they were 12-years-old or younger. In the report from the Swedish National Institute of Public Health, gambling problems are related to health problems and risky alcohol consumption. The highest problem rate is found among men aged 18 to 24; almost 1 in 10 had some gambling problems. The share of problem gamblers is found to be twice as high among the under-age gamblers as it is among the population as a whole. Young people gamble less but develop gambling problems to a larger extent than adult gamblers. In this article young people's gambling and their gambling careers are analysed as a natural part of their internalisation of other adult habits. PMID:21629581

Workplace mental health: developing an integrated intervention approach.

PubMed

LaMontagne, Anthony D; Martin, Angela; Page, Kathryn M; Reavley, Nicola J; Noblet, Andrew J; Milner, Allison J; Keegel, Tessa; Smith, Peter M

2014-05-09

Mental health problems are prevalent and costly in working populations. Workplace interventions to address common mental health problems have evolved relatively independently along three main threads or disciplinary traditions: medicine, public health, and psychology. In this Debate piece, we argue that these three threads need to be integrated to optimise the prevention of mental health problems in working populations. To realise the greatest population mental health benefits, workplace mental health intervention needs to comprehensively 1) protect mental health by reducing work-related risk factors for mental health problems; 2) promote mental health by developing the positive aspects of work as well as worker strengths and positive capacities; and 3) address mental health problems among working people regardless of cause. We outline the evidence supporting such an integrated intervention approach and consider the research agenda and policy developments needed to move towards this goal, and propose the notion of integrated workplace mental health literacy. An integrated approach to workplace mental health combines the strengths of medicine, public health, and psychology, and has the potential to optimise both the prevention and management of mental health problems in the workplace.

Food production -- problems and prospects.

PubMed

Anifowoshe, T O

1990-03-01

Improvements are needed in balancing the problems associated with population growth and food production. A review of the problems of rapid population growth and declining food production and suggestions for resolution are given. World population has increased over the past 10 years by 760 million, which is equal to adding the combined population of Africa and South America. Future increases are expected to bring total population to 6.1 billion by the year 2000 and 8.2 billion in 2025 (exponential increases). Food production/capita has declined since 1971 in the world and in Nigeria, particularly in the recent past. The food production problem is technical, environmental, social, political, and economic. Various scientific and technological methods for increasing food production are identified: mechanization, irrigation, use of fertilizers, control of weeds and insects, new varieties of farm animals or high-yielding strains of grain, land reclamation, soil conservation, river basin development, adequate storage facilities, infrastructure development, and birth control. Economic and social approaches involve short-term and long-term strategies in social readjustment and institutional change. For instance, large scale farmers should become contract growers for certain firms. Bureaucratic red tape should be eliminated in institutions which provide agricultural services. Environmental problems need urgent attention. Some of these problems are soil erosion from mechanization, water salinization from irrigation, accumulation of DDT in food and water and animal life from pesticide use, and water pollution from chemical fertilizers. Food production can be increased with more ecologically sound practices. Information about weather and weather forecasting allows for more suitable land management. The influence of rainfall (the amount and distribution) in Nigeria is greater than any other climatic factor. Solar radiation is a significant feature in production of dry matter and yield. Shifting cultivation and land tenure systems should involve conservation farming techniques. organic manures and appropriate use of chemical fertilizers can raise soil fertility. Other problems are identified as the spread of bilharzia and the settlement of nomadic tribes.

Gambling in Western and Eastern Europe: the example of Hungary.

PubMed

Kun, Bernadette; Balázs, Hedvig; Arnold, Petra; Paksi, Borbála; Demetrovics, Zsolt

2012-03-01

The history of gambling in post-socialist countries is noticeably different from that of other countries in Europe. The goal of this study was therefore twofold: Firstly, to systematically review all European epidemiological studies related to excessive gambling in the general adult population, and secondly, to provide an overview of the state of gambling in Hungary based on the first ever nationwide representative survey, setting the results against the backdrop of the earlier European studies. A systematic review was carried out of European gambling studies which focus on a representative adult general population. Hungarian data was obtained from the National Survey on Addiction Problems in Hungary general adult population survey (N = 2,710). Pathological gambling was measured by the South Oaks Gambling Screen. Lifetime prevalence of excessive gambling (problem and pathological gambling) in the general adult population of European countries varies between 1.1% (Italy and Spain) and 6.5% (Estonia). In Hungary, the prevalence of problem gambling is 1.9%, with pathological gambling at 1.4%. The socio-demographic characteristics of the results are similar to those of other European countries. Using epidemiological data from the general adult populations of two post-socialist nations, it was possible to compare the results with data from 12 other European countries. Based on the data available, the extremely rapid liberation of the gambling market in the post-socialist countries has led to a similarly swift escalation in associated gambling problems.

Sequential Insertion Heuristic with Adaptive Bee Colony Optimisation Algorithm for Vehicle Routing Problem with Time Windows

PubMed Central

Jawarneh, Sana; Abdullah, Salwani

2015-01-01

This paper presents a bee colony optimisation (BCO) algorithm to tackle the vehicle routing problem with time window (VRPTW). The VRPTW involves recovering an ideal set of routes for a fleet of vehicles serving a defined number of customers. The BCO algorithm is a population-based algorithm that mimics the social communication patterns of honeybees in solving problems. The performance of the BCO algorithm is dependent on its parameters, so the online (self-adaptive) parameter tuning strategy is used to improve its effectiveness and robustness. Compared with the basic BCO, the adaptive BCO performs better. Diversification is crucial to the performance of the population-based algorithm, but the initial population in the BCO algorithm is generated using a greedy heuristic, which has insufficient diversification. Therefore the ways in which the sequential insertion heuristic (SIH) for the initial population drives the population toward improved solutions are examined. Experimental comparisons indicate that the proposed adaptive BCO-SIH algorithm works well across all instances and is able to obtain 11 best results in comparison with the best-known results in the literature when tested on Solomon’s 56 VRPTW 100 customer instances. Also, a statistical test shows that there is a significant difference between the results. PMID:26132158

[Infection by hepatitis virus among the indigenous populations of South America: a review of the problem].

PubMed

Echevarría, J M; Blitz-Dorfman, L; Pujot, F H

1996-09-01

After the report of the epidemic outbreak of delta hepatitis among the Yukpa amerindians in the early 80s, the viral hepatitis arose as an important health problem in all the Amerindian communities from the north of South America and the Amazonian Basin. Despite the few data available, the results obtained in different communities from Venezuela (Yukpa, Barí, Yanomami) have shown a high endemicity of hepatitis B and D virus infections and a significant prevalence of hepatitis E virus-specific antibody among their members. By contrast, the infection by hepatitis C virus, which is present in all the urban areas from South America, seems uncommon, or even absent among some Amerindian populations. At the moment, a satisfactory explanation for this findings has not yet been arised. However, it could be possible that the margination of these populations regarding the health care system has been keeping them free of an infection largely linked worldwide to iatrogeny. Vaccination of Amerindian populations against hepatitis B should be taken as a priority of the health care programs. Moreover, such programs should consider the iatrogenic transmission of the HCV as a matter of concern regarding such populations, since parenterally transmitted hepatitis viruses seems to spread quickly among their members once they are introduced, giving rise to serious health problems.

A qualitative systematic review of published work on disclosure and help-seeking for domestic violence and abuse among women from ethnic minority populations in the UK.

PubMed

Femi-Ajao, Omolade; Kendal, Sarah; Lovell, Karina

2018-03-07

Domestic violence and abuse has been recognised as an international public health problem. However, the pervasiveness of the problem is unknown due in part to underreporting, especially among women from ethnic minority populations. In relation to this group, this review seeks to explore: (1) the barriers to disclosure; (2) the facilitators of help-seeking; and (3) self-perceived impacts of domestic violence. We systematically identified published qualitative studies conducted among women from ethnic minority populations in the UK. Data analysis was completed using thematic analysis approach. 562 papers were identified and eight papers from four studies conducted among women from ethnic minority populations in the UK met the inclusion criteria and were reviewed. Barriers to disclosure include: Immigration status, community influences, problems with language and interpretation, and unsupportive attitudes of staff within mainstream services. Facilitators of help-seeking were: escalation of abuse and safety of children. Self-perceived impact of abuse includes: shame, denial, loss of identity and lack of choice. There is an on-going need for staff from domestic violence services to be aware of the complexities within which women from ethnic minority populations experience domestic violence and abuse.

[Population and development].

PubMed

Trias, M

1987-01-01

Human reproduction and development are contrasted; they are intimately linked despite the fact that they may be considered antitheses of each other from many points of view. Presently technological development and the advance of humans into every available corner of living space threaten to place the whole world environment in danger. The Green revolution of the 1960s addressed problems of underproduction of food for the world's population, without providing for the effective distribution of the new surpluses, and without addressing the problem of the ecological impact. 2 trends which are regarded by some with alarm: the migration of populations to the cities and the aging of the population with the connected burden on health care systems, are inevitable, and it is not clear that they are completely negative trends. Addressing these issues will have positive effects in the long run: congestion in the cities, the result of mechanization of rural industry which also results in a greater abundance of agricultural products necessary to society, should force serious consideration of problems such as solid waste management. Coming to terms with the costs of intervention to save lives among the very frail elderly and the prematurely born will have the effect of bringing controversial topics such as euthenasia and eugenics to discussion. The important role played by economic development in the braking of population expansion is underlined.

Demographics of the gay and lesbian population in the United States: evidence from available systematic data sources.

PubMed

Black, D; Gates, G; Sanders, S; Taylor, L

2000-05-01

This work provides an overview of standard social science data sources that now allow some systematic study of the gay and lesbian population in the United States. For each data source, we consider how sexual orientation can be defined, and we note the potential sample sizes. We give special attention to the important problem of measurement error, especially the extent to which individuals recorded as gay and lesbian are indeed recorded correctly. Our concern is that because gays and lesbians constitute a relatively small fraction of the population, modest measurement problems could lead to serious errors in inference. In examining gays and lesbians in multiple data sets we also achieve a second objective: We provide a set of statistics about this population that is relevant to several current policy debates.

TOPICAL PROBLEMS: The phenomenological theory of world population growth

NASA Astrophysics Data System (ADS)

Kapitza, Sergei P.

1996-01-01

Of all global problems world population growth is the most significant. Demographic data describe this process in a concise and quantitative way in its past and present. Analysing this development it is possible by applying the concepts of systems analysis and synergetics, to work out a mathematical model for a phenomenological description of the global demographic process and to project its trends into the future. Assuming self-similarity as the dynamic principle of development, growth can be described practically over the whole of human history, assuming the growth rate to be proportional to the square of the number of people. The large parameter of the theory and the effective size of a coherent population group is of the order of 105 and the microscopic parameter of the phenomenology is the human lifespan. The demographic transition — a transition to a stabilised world population of some 14 billion in a foreseeable future — is a systemic singularity and is determined by the inherent pattern of growth of an open system, rather than by the lack of resources. The development of a quantitative nonlinear theory of the world population is of interest for interdisciplinary research in anthropology and demography, history and sociology, for population genetics and epidemiology, for studies in evolution of humankind and the origin of man. The model also provides insight into the stability of growth and the present predicament of humankind, and provides a setting for discussing the main global problems.

Continuous and Discrete Structured Population Models with Applications to Epidemiology and Marine Mammals

NASA Astrophysics Data System (ADS)

Tang, Tingting

In this dissertation, we develop structured population models to examine how changes in the environmental affect population processes. In Chapter 2, we develop a general continuous time size structured model describing a susceptible-infected (SI) population coupled with the environment. This model applies to problems arising in ecology, epidemiology, and cell biology. The model consists of a system of quasilinear hyperbolic partial differential equations coupled with a system of nonlinear ordinary differential equations that represent the environment. We develop a second-order high resolution finite difference scheme to numerically solve the model. Convergence of this scheme to a weak solution with bounded total variation is proved. We numerically compare the second order high resolution scheme with a first order finite difference scheme. Higher order of convergence and high resolution property are observed in the second order finite difference scheme. In addition, we apply our model to a multi-host wildlife disease problem, questions regarding the impact of the initial population structure and transition rate within each host are numerically explored. In Chapter 3, we use a stage structured matrix model for wildlife population to study the recovery process of the population given an environmental disturbance. We focus on the time it takes for the population to recover to its pre-event level and develop general formulas to calculate the sensitivity or elasticity of the recovery time to changes in the initial population distribution, vital rates and event severity. Our results suggest that the recovery time is independent of the initial population size, but is sensitive to the initial population structure. Moreover, it is more sensitive to the reduction proportion to the vital rates of the population caused by the catastrophe event relative to the duration of impact of the event. We present the potential application of our model to the amphibian population dynamic and the recovery of a certain plant population. In addition, we explore, in details, the application of the model to the sperm whale population in Gulf of Mexico after the Deepwater Horizon oil spill. In Chapter 4, we summarize the results from Chapter 2 and Chapter 3 and explore some further avenues of our research.

Population and the Future: From Bucharest (1974) to Mexico City (1984). Summary Report of the United Nations Fund for Population Activities Briefing for Non-Governmental Organizations in New York (2nd, New York, New York, February 16, 1983).

ERIC Educational Resources Information Center

De Vel Muller, Robert

The major objectives of this briefing are to inform non-governmental organizations (NGOs) of population problems and progress worldwide and to provide information on the International Conference on Population to be held in Mexico City in 1984. The bulk of the report summarizes the group meetings and followup discussions held to examine four major…

[The representation of population density in school atlases: a critical examination of population maps].

PubMed

Schroder, P

1997-01-01

The author critiques the way population density is represented in school atlases, focusing on those used in German-speaking countries. After a discussion of the methodological problems underlying such representations, he selects examples from several German atlases to illustrate the transmission of contradictory, misleading, or out-of-date information. He also suggests ways to improve this situation, including better teaching of underlying cartographical issues and the use of a dot system to illustrate population density.

Nonidentifiability of population size from capture-recapture data with heterogeneous detection probabilities

USGS Publications Warehouse

Link, W.A.

2003-01-01

Heterogeneity in detection probabilities has long been recognized as problematic in mark-recapture studies, and numerous models developed to accommodate its effects. Individual heterogeneity is especially problematic, in that reasonable alternative models may predict essentially identical observations from populations of substantially different sizes. Thus even with very large samples, the analyst will not be able to distinguish among reasonable models of heterogeneity, even though these yield quite distinct inferences about population size. The problem is illustrated with models for closed and open populations.

Coexisting Psychiatric Problems and Stressful Life Events in Adults with Symptoms of ADHD--A Large Swedish Population-Based Study of Twins

ERIC Educational Resources Information Center

Friedrichs, Bettina; Igl, Wilmar; Larsson, Henrik; Larsson, Jan-Olov

2012-01-01

Objective: To explore the associations of subtypes of adult ADHD with other psychiatric problems, stressful life events, and sex differences. Method: Odds ratios were calculated using information from 17,899 participants from a population-based survey of adult twins born in Sweden between 1959 and 1985. Results: Symptoms of attention deficit…

The Combined Burden of Cognitive, Executive Function, and Psychosocial Problems in Children with Epilepsy: A Population-Based Study

ERIC Educational Resources Information Center

Hoie, B.; Sommerfelt, K.; Waaler, P. E.; Alsaker, F. D.; Skeidsvoll, H.; Mykletun, A.

2008-01-01

The combined burden of psychosocial (Achenbach scales), cognitive (Raven matrices), and executive function (EF) problems was studied in a population-based sample of 6- to 12-year-old children with epilepsy (n = 162; 99 males, 63 females) and in an age- and sex-matched control group (n = 107; 62 males, 45 females). Approximately 35% of the children…

Teacher Resource Book for Population Pressure in Indonesia, Problems of Industrialization in Eurasia, Power Blocs in Eurasia. Man on the Earth Series.

ERIC Educational Resources Information Center

Gunn, Angus

This teacher's resource book is a guide to three intermediate texts about Eurasia entitled Population Pressure in Indonesia, Problems of Industrialization in Eurasia, and Power Blocs in Eurasia. The texts are part of the series, Man on the Earth, which probes broad-based issues confronting mankind. The resource book distinguishes 18 major concepts…

Individual heterogeneity and identifiability in capture-recapture models

USGS Publications Warehouse

Link, W.A.

2004-01-01

Individual heterogeneity in detection probabilities is a far more serious problem for capture-recapture modeling than has previously been recognized. In this note, I illustrate that population size is not an identifiable parameter under the general closed population mark-recapture model Mh. The problem of identifiability is obvious if the population includes individuals with pi = 0, but persists even when it is assumed that individual detection probabilities are bounded away from zero. Identifiability may be attained within parametric families of distributions for pi, but not among parametric families of distributions. Consequently, in the presence of individual heterogeneity in detection probability, capture-recapture analysis is strongly model dependent.

WKB theory of large deviations in stochastic populations

NASA Astrophysics Data System (ADS)

Assaf, Michael; Meerson, Baruch

2017-06-01

Stochasticity can play an important role in the dynamics of biologically relevant populations. These span a broad range of scales: from intra-cellular populations of molecules to population of cells and then to groups of plants, animals and people. Large deviations in stochastic population dynamics—such as those determining population extinction, fixation or switching between different states—are presently in a focus of attention of statistical physicists. We review recent progress in applying different variants of dissipative WKB approximation (after Wentzel, Kramers and Brillouin) to this class of problems. The WKB approximation allows one to evaluate the mean time and/or probability of population extinction, fixation and switches resulting from either intrinsic (demographic) noise, or a combination of the demographic noise and environmental variations, deterministic or random. We mostly cover well-mixed populations, single and multiple, but also briefly consider populations on heterogeneous networks and spatial populations. The spatial setting also allows one to study large fluctuations of the speed of biological invasions. Finally, we briefly discuss possible directions of future work.

Recent progress and challenges in population genetics of polyploid organisms: an overview of current state-of-the-art molecular and statistical tools.

PubMed

Dufresne, France; Stift, Marc; Vergilino, Roland; Mable, Barbara K

2014-01-01

Despite the importance of polyploidy and the increasing availability of new genomic data, there remain important gaps in our knowledge of polyploid population genetics. These gaps arise from the complex nature of polyploid data (e.g. multiple alleles and loci, mixed inheritance patterns, association between ploidy and mating system variation). Furthermore, many of the standard tools for population genetics that have been developed for diploids are often not feasible for polyploids. This review aims to provide an overview of the state-of-the-art in polyploid population genetics and to identify the main areas where further development of molecular techniques and statistical theory is required. We review commonly used molecular tools (amplified fragment length polymorphism, microsatellites, Sanger sequencing, next-generation sequencing and derived technologies) and their challenges associated with their use in polyploid populations: that is, allele dosage determination, null alleles, difficulty of distinguishing orthologues from paralogues and copy number variation. In addition, we review the approaches that have been used for population genetic analysis in polyploids and their specific problems. These problems are in most cases directly associated with dosage uncertainty and the problem of inferring allele frequencies and assumptions regarding inheritance. This leads us to conclude that for advancing the field of polyploid population genetics, most priority should be given to development of new molecular approaches that allow efficient dosage determination, and to further development of analytical approaches to circumvent dosage uncertainty and to accommodate 'flexible' modes of inheritance. In addition, there is a need for more simulation-based studies that test what kinds of biases could result from both existing and novel approaches. © 2013 John Wiley & Sons Ltd.

Improving population management through pharmacist-primary care integration: a pilot study.

PubMed

Kennedy, Amanda G; Chen, Harry; Corriveau, Michele; MacLean, Charles D

2015-02-01

Pharmacists have unique skills that may benefit primary care practices. The objective of this demonstration project was to determine the impact of integrating pharmacists into patient-centered medical homes, with a focus on population management. Pharmacists were partnered into 5 primary care practices in Vermont 1 day per week to provide direct patient care, population-based medication management, and prescriber education. The main measures included a description of drug therapy problems identified and cost avoidance models. The pharmacists identified 708 drug therapy problems through direct patient care (336/708; 47.5%), population-based strategies (276/708; 38.9%), and education (96/708; 13.6%). Common population-based strategies included adjusting doses and discontinuing unnecessary medications. Pharmacists' recommendations to correct drug therapy problems were accepted by prescribers 86% of the time, when data about acceptance were known. Of the 49 recommendations not accepted, 47/49 (96%) were population-based and 2/49 (4%) were related to direct patient care. The cost avoidance model suggests $2.11 in cost was avoided for every $1.00 spent on a pharmacist ($373,092/$176,690). There was clear value in integrating pharmacists into primary care teams. Their inclusion prevented adverse drug events, avoided costs, and improved patient outcomes. Primary care providers should consider pharmacists well suited to offer direct patient care, population-based management, and prescriber education to their practices. To be successful, pharmacists must have full permission to document findings in the primary care practices' electronic health records. Given that many pharmacist services do not involve billable activities, sustainability requires identifying alternative funding mechanisms that do not rely on a traditional fee-for-service approach.

Teacher's Guide in Population Education for Social Studies, First Year-Fourth Year. Secondary Level. (Revised for Muslim Filipinos).

ERIC Educational Resources Information Center

Department of Education and Culture, Manila (Philippines).

Revised to be in accordance with the customs, traditions, beliefs, and practices of the Muslim Filipinos, these social studies units will help secondary-level Filipino students understand world population problems and develop the necessary skills, attitudes, and values that will lead them to make rational decisions about population matters,…

"Every Family": A Population Approach to Reducing Behavioral and Emotional Problems in Children Making the Transition to School

ERIC Educational Resources Information Center

Sanders, Matthew R.; Ralph, Alan; Sofronoff, Kate; Gardiner, Paul; Thompson, Rachel; Dwyer, Sarah; Bidwell, Kerry

2008-01-01

A large-scale population trial using the Triple P-Positive Parenting Program (TPS) was evaluated. The target population was all parents of 4- to 7-year-old children residing in ten geographical catchment areas in Brisbane (intervention communities) and ten sociodemographically matched catchment areas from Sydney (5) and Melbourne (5), care as…

The effect of continuous low dose-rate gamma irradiation on cell population kinetics of lymphoid tissue

NASA Technical Reports Server (NTRS)

Foster, B. R.

1973-01-01

The problem studied involved cell proliferation in mice thymus undergoing irradiation at a dose rate of 10 roetgens/day for 105 days. Specifically, the aim was to determine wheather or not a steady state of cell population can be established for the indicated period of time and what compensatory mechanisms of cell population are involved.

National Rehabilitation and Development Plan, 1984-1987.

PubMed

1987-01-01

This document reprints sections of Bolivia's National Rehabilitation and Development Plan for 1984-87. The plan identifies Bolivia's greatest problem as the low growth rate of its productive population and calls for a redistribution of population in accordance with the optimal exploitation of the country's natural resources. A further objective, contingent upon a substantial improvement in the nutrition and health of the population, is to improve the country's educational system. The growth rate of the population must be increased in accordance with a strategy that allows productivity to increase even faster. The required changes in demographics include a rapid increase in life expectancy at birth, an increase in agriculturally-oriented immigration, and moderate urban growth. Specific policies include providing education to increase literacy, promoting breast feeding and health as well as the rights of women, eliminating sex discrimination in formal education, reducing mortality, influencing migration and population settlements, and promoting agricultural technology. Specific health initiatives should lead to increased accessibility to medical care, research to identify health problems related to specific populations, promotion of breast feeding, promotion of community participation in provision of health services, development of sanitation programs, and promotion of sex education to reduce the incidence of unsafe abortion.

Alcohol use patterns, problems and policies in Malaysia.

PubMed

Jernigan, D H; Indran, S K

1997-12-01

The roots of Malaysia's drinking patterns lie in the introduction of most forms of alcohol by Europeans. Although Malaysia today has relatively low per capita alcohol consumption, available studies and interviews with alcohol industry officials point to a small segment of the population that drinks heavily and causes and experiences substantial alcohol related-problems. Indians are over-represented in this sub-population, but studies also reveal substantial drinking problems among Chinese and Malays. Government officials categorize alcohol as an Indian problem. The government devotes little resources to monitoring drinking patterns, use or problems; or to preventing, treating or educating the public about alcohol-related problems. Alcohol-producing transnational corporations own shares of all of Malaysia's major alcohol producers. In the face of high alcohol taxes and a ban on broadcast advertising of alcoholic beverages, these companies market alcohol aggressively, making health claims, targeting heavy drinkers and encouraging heavy drinking, employing indirect advertising, and using women in seductive poses and occupations to attract the mostly male drinking population. Monitoring of the country's alcohol problems is greatly needed in order to establish alcohol consumption more clearly as a national health and safety issue, while stronger controls and greater corporate responsibility are required to control alcohol marketing.

The population structure and recent colonization history of Oregon threespine stickleback determined using restriction-site associated DNA-sequencing.

PubMed

Catchen, Julian; Bassham, Susan; Wilson, Taylor; Currey, Mark; O'Brien, Conor; Yeates, Quick; Cresko, William A

2013-06-01

Understanding how genetic variation is partitioned across genomes within and among populations is a fundamental problem in ecological and evolutionary genetics. To address this problem, we studied the threespine stickleback fish, which has repeatedly undergone parallel phenotypic and genetic differentiation when oceanic fish have invaded freshwater habitats. While significant evolutionary genetic research has been performed using stickleback from geographic regions that have been deglaciated in the last 20 000 years, less research has focused on freshwater populations that predate the last glacial maximum. We performed restriction-site associated DNA-sequencing (RAD-seq) based population genomic analyses on stickleback from across Oregon, which was not glaciated during the last maximum. We sampled stickleback from coastal, Willamette Basin and central Oregon sites, analysed their genetic diversity using RAD-seq, performed structure analyses, reconstructed their phylogeographic history and tested the hypothesis of recent stickleback introduction into central Oregon, where incidence of this species was only recently documented. Our results showed a clear phylogeographic break between coastal and inland populations, with oceanic populations exhibiting the lowest levels of divergence from one another. Willamette Basin and central Oregon populations formed a clade of closely related populations, a finding consistent with a recent introduction of stickleback into central Oregon. Finally, genome-wide analysis of genetic diversity (π) and correlations of alleles within individuals in subpopulations (FIS) supported a role for introgressive hybridization in coastal populations and a recent expansion in central Oregon. Our results exhibit the power of next-generation sequencing genomic approaches such as RAD-seq to identify both historical population structure and recent colonization history. © 2013 John Wiley & Sons Ltd.

Evaluation of the Effectiveness of a Problem-Solving Intervention Addressing Barriers to Cardiovascular Disease Prevention Behaviors in 3 Underserved Populations: Colorado, North Carolina, West Virginia, 2009

PubMed Central

Bryant, Lucinda L.; Leary, Janie M.; Vu, Maihan B.; Hill-Briggs, Felicia; Samuel-Hodge, Carmen D.; McMilin, Colleen R.; Keyserling, Thomas C.

2014-01-01

Introduction In low-income and underserved populations, financial hardship and multiple competing roles and responsibilities lead to difficulties in lifestyle change for cardiovascular disease (CVD) prevention. To improve CVD prevention behaviors, we adapted, pilot-tested, and evaluated a problem-solving intervention designed to address barriers to lifestyle change. Methods The sample consisted of 81 participants from 3 underserved populations, including 28 Hispanic or non-Hispanic white women in a western community (site 1), 31 African-American women in a semirural southern community (site 2), and 22 adults in an Appalachian community (site 3). Incorporating focus group findings, we assessed a standardized intervention involving 6-to-8 week group sessions devoted to problem-solving in the fall of 2009. Results Most sessions were attended by 76.5% of participants, demonstrating participant adoption and engagement. The intervention resulted in significant improvement in problem-solving skills (P < .001) and perceived stress (P < .05). Diet, physical activity, and weight remained stable, although 72% of individuals reported maintenance or increase in daily fruit and vegetable intake, and 67% reported maintenance or increase in daily physical activity. Conclusion Study results suggest the intervention was acceptable to rural, underserved populations and effective in training them in problem-solving skills and stress management for CVD risk reduction. PMID:24602586

Differences in problem-solving between canid populations: Do domestication and lifetime experience affect persistence?

PubMed

Brubaker, Lauren; Dasgupta, Sandipan; Bhattacharjee, Debottam; Bhadra, Anindita; Udell, Monique A R

2017-07-01

Past research has suggested that a variety of factors, phylogenetic and ontogenetic, play a role in how canines behave during problem-solving tasks and the degree to which the presence of a human influences their problem-solving behaviour. While comparisons between socialized wolves and domestic dogs have commonly been used to tease apart these predictive factors, in many cases a single dog population, often pets, have been used for these comparisons. Less is understood about how different populations of dogs may behave when compared with wolves, or with each other, during an independent problem-solving task. This experiment compared the independent persistence of four populations of canines (two groups of pet domestic dogs, a group of free-ranging domestic dogs, and human-socialized wolves) on an independent problem-solving task in the presence of an on looking human. Results showed that wolves persisted the most at the task while free-ranging dogs persisted the least. Free-ranging dogs gazed at the human experimenter for the longest durations during the task. While further research is needed to understand why these differences exist, this study demonstrates that dogs, even those living outside human homes as scavengers, show comparatively low levels of persistence when confronted with a solvable task in the presence of a human as well as significantly greater duration of human-directed gaze when compared with wolves.

Bistability, non-ergodicity, and inhibition in pairwise maximum-entropy models

PubMed Central

Grün, Sonja; Helias, Moritz

2017-01-01

Pairwise maximum-entropy models have been used in neuroscience to predict the activity of neuronal populations, given only the time-averaged correlations of the neuron activities. This paper provides evidence that the pairwise model, applied to experimental recordings, would produce a bimodal distribution for the population-averaged activity, and for some population sizes the second mode would peak at high activities, that experimentally would be equivalent to 90% of the neuron population active within time-windows of few milliseconds. Several problems are connected with this bimodality: 1. The presence of the high-activity mode is unrealistic in view of observed neuronal activity and on neurobiological grounds. 2. Boltzmann learning becomes non-ergodic, hence the pairwise maximum-entropy distribution cannot be found: in fact, Boltzmann learning would produce an incorrect distribution; similarly, common variants of mean-field approximations also produce an incorrect distribution. 3. The Glauber dynamics associated with the model is unrealistically bistable and cannot be used to generate realistic surrogate data. This bimodality problem is first demonstrated for an experimental dataset from 159 neurons in the motor cortex of macaque monkey. Evidence is then provided that this problem affects typical neural recordings of population sizes of a couple of hundreds or more neurons. The cause of the bimodality problem is identified as the inability of standard maximum-entropy distributions with a uniform reference measure to model neuronal inhibition. To eliminate this problem a modified maximum-entropy model is presented, which reflects a basic effect of inhibition in the form of a simple but non-uniform reference measure. This model does not lead to unrealistic bimodalities, can be found with Boltzmann learning, and has an associated Glauber dynamics which incorporates a minimal asymmetric inhibition. PMID:28968396

Bistability, non-ergodicity, and inhibition in pairwise maximum-entropy models.

PubMed

Rostami, Vahid; Porta Mana, PierGianLuca; Grün, Sonja; Helias, Moritz

2017-10-01

Pairwise maximum-entropy models have been used in neuroscience to predict the activity of neuronal populations, given only the time-averaged correlations of the neuron activities. This paper provides evidence that the pairwise model, applied to experimental recordings, would produce a bimodal distribution for the population-averaged activity, and for some population sizes the second mode would peak at high activities, that experimentally would be equivalent to 90% of the neuron population active within time-windows of few milliseconds. Several problems are connected with this bimodality: 1. The presence of the high-activity mode is unrealistic in view of observed neuronal activity and on neurobiological grounds. 2. Boltzmann learning becomes non-ergodic, hence the pairwise maximum-entropy distribution cannot be found: in fact, Boltzmann learning would produce an incorrect distribution; similarly, common variants of mean-field approximations also produce an incorrect distribution. 3. The Glauber dynamics associated with the model is unrealistically bistable and cannot be used to generate realistic surrogate data. This bimodality problem is first demonstrated for an experimental dataset from 159 neurons in the motor cortex of macaque monkey. Evidence is then provided that this problem affects typical neural recordings of population sizes of a couple of hundreds or more neurons. The cause of the bimodality problem is identified as the inability of standard maximum-entropy distributions with a uniform reference measure to model neuronal inhibition. To eliminate this problem a modified maximum-entropy model is presented, which reflects a basic effect of inhibition in the form of a simple but non-uniform reference measure. This model does not lead to unrealistic bimodalities, can be found with Boltzmann learning, and has an associated Glauber dynamics which incorporates a minimal asymmetric inhibition.

[The paradox of motherhood].

PubMed

Ouaidou, N G

1990-08-01

All Sahelian countries are working to define their population policies. A population policy document avoids dispersion and duplication. It opens the path to efficiency. It makes it easier to achieve governmental socioeconomic objectives. Various recent population-related meetings have at least two points in common: they aim to overstep and improve a given situation and are at the same time some examples of implementing the Ndjamena action program, adopted in January 1989. All these population-centered actions return to the problem of adolescent fertility--a poignant problem. Adolescent pregnancy is a major source of family and social break-ups. This paradox of motherhood makes a violent storm burst in the skies ordinarily serene with joy and hope. It is an enemy perverse to economic development and social progress. Adolescent motherhood is a phenomenon which complicates and aggravates population problems and is taboo to the point it is still imperceptible, unknown. It is a problem of premier importance in the Sahel. Pregnancy strikes a woman so very unprepared for motherhood and its demands. It risks the life of a being which is preparing itself to enter the world. Adolescent pregnancy has equally tragic health effects: poorly performed underground abortions and maternal and infant deaths. Adolescent fertility is a burning problem regardless of the perspective (demographic, economic, social, or health). In Sahelian countries, one is beginning to be interested in and to speak about it. It will be necessary to search for solutions. Schools must be a top target for all activities aiming to check adolescent fertility. The emphasis must be on information, education, and responsibility of girls, boys, teachers, and parents. Education and training are of capital importance for socioeconomic development of the Sahel. All activities implemented in the education sector should include a large place for family life education in pregnancy prevention.

Second Amman Declaration on Population and Development in the Arab World.

PubMed

1992-01-01

Many demographic changes have occurred in the Arab region. Population increased from 132 million in 1974 to 237 million in 1992. In preparation for the International Conference on Population and Development in 1994, the Arab Population Conference was held in April 1993. This document summarizes the Arab conference proceedings: preamble, general principles, objectives, and recommendations for human development, the environment, population distribution and urbanization, international migration, women in development, maternal and child health and family planning, IEC, nongovernmental development programs, special topics, structural adjustment and population policies, research, and international cooperation. Arab countries were convinced that clear, comprehensive population policies were needed and should be integrated into development programs. Population policies must be based on the achievement of a satisfactory quality of life and integrity for the family as the basic unit of society. Women should be enabled to perform their full role as citizens. Children have a right to a happy, healthy, and secure life. Population is interconnected with development and should not be treated in isolation. The population problems of those in Israeli occupied territory should be addressed with consideration for the demographic pressure from occupational authorities. Arab states should provide family planning services as a basic human right of couples. Environmental concerns must be considered within development strategies. Reforms need to be made to correct imbalances between economic and social conditions and population problems. Arab countries must be involved in restructuring the world economy with the aim of balancing North and South trade. Rescheduling of debt servicing must be achieved. The industrialized countries must "curb excessive consumerism and reduce huge expenditures on armaments." Individual country population policy should be constructed within a pan-Arab framework and an integrated development policy. There should be respect for individual human dignity and rights and the promotion of democracy, collective activity, and individual initiative.

Education for all draws upon population education messages.

PubMed

1991-01-01

In May 1991, UNESCO and the Ministry of Education of Pakistan sponsored a Regional Workshop for the Integration of Population Education in Asia-Pacific Programme of Education for All in Islamabad, Pakistan. Prior to the workshop, resource persons and experts met to develop guidelines for participants that were geared towards curriculum and material needs and core population education messages. 1 workshop group addressed integration of population education messages into primary education and the other into literacy programs. All participants observed and analyzed the problems and needs of a Muslim community and Saidpur village. The 1st group visited primary schools and spoke to teachers. The participants agreed that population education messages should be integrated into social studies, science, languages, and religion subjects at grade levels 3-5. The messages should include population related beliefs and values, problems of population growth, small family size, responsible parenthood, sex preference, population and development, the role of elders, and improving the status of women. They tested 4 of 11 developed lesson plans. Both teachers and students were generally pleased, but believed that posters and illustrations would better the plans. The other group conducted a needs assessment survey among 27 Muslim families. Participants found 100 population related issues that needed to be addressed in literacy programs. These issues fit into 6 categories and the group focused on social and cultural values and beliefs. Participants developed materials that highlighted several topics, such as early marriage and preference for males. They used puppet shows, puzzle games, posters and discussions, and story telling with pictures to communicate the messages. Puppet shows were the most popular method among housewives.

Cortisol in the morning and dimensions of anxiety, depression, and aggression in children from a general population and clinic-referred cohort: An integrated analysis. The TRAILS study.

PubMed

Dietrich, Andrea; Ormel, Johan; Buitelaar, Jan K; Verhulst, Frank C; Hoekstra, Pieter J; Hartman, Catharina A

2013-08-01

Anxiety and depressive problems have often been related to higher hypothalamic-pituitary-adrenal (HPA)-axis activity (basal morning cortisol levels and cortisol awakening response [CAR]) and externalizing problems to lower HPA-axis activity. However, associations appear weaker and more inconsistent than initially assumed. Previous studies from the Tracking Adolescents Individual Lives Study (TRAILS) suggested sex-differences in these relationships and differential associations with specific dimensions of depressive problems in a general population sample of children (10-12 years). Using the TRAILS population sample (n=1604), we tested hypotheses on the association between single day cortisol (basal morning levels and CAR) and specifically constructed dimensions of anxiety (cognitive versus somatic), depressive (cognitive-affective versus somatic), and externalizing problems (reactive versus proactive aggression), and explored the modifying role of sex. Moreover, we repeated analyses in an independent same-aged clinic-referred sample (n=357). Structural Equation Modeling was used to investigate the association between cortisol and higher- and lower-order (thus, broad and specific) problem dimensions based on self-reports in an integrated model. Overall, findings were consistent across the population and clinic-referred samples, as well as with the existing literature. Most support was found for higher cortisol (mainly CAR) in relation to depressive problems. However, in general, associations were weak in both samples. Therefore, the present results shed doubt on the relevance of single day cortisol measurements for problem behaviors in the milder range. Associations may be stronger in more severe or persistent psychopathology. Copyright © 2012 Elsevier Ltd. All rights reserved.

Order of events matter: comparing discrete models for optimal control of species augmentation.

PubMed

Bodine, Erin N; Gross, Louis J; Lenhart, Suzanne

2012-01-01

We investigate optimal timing of augmentation of an endangered/threatened species population in a target region by moving individuals from a reserve or captive population. This is formulated as a discrete-time optimal control problem in which augmentation occurs once per time period over a fixed number of time periods. The population model assumes the Allee effect growth functions in both target and reserve populations and the control objective is to maximize the target and reserve population sizes over the time horizon while accounting for costs of augmentation. Two possible orders of events are considered for different life histories of the species relative to augmentation time: move individuals either before or after population growth occurs. The control variable is the proportion of the reserve population to be moved to the target population. We develop solutions and illustrate numerical results which indicate circumstances for which optimal augmentation strategies depend upon the order of events.

Adaptively resizing populations: Algorithm, analysis, and first results

NASA Technical Reports Server (NTRS)

Smith, Robert E.; Smuda, Ellen

1993-01-01

Deciding on an appropriate population size for a given Genetic Algorithm (GA) application can often be critical to the algorithm's success. Too small, and the GA can fall victim to sampling error, affecting the efficacy of its search. Too large, and the GA wastes computational resources. Although advice exists for sizing GA populations, much of this advice involves theoretical aspects that are not accessible to the novice user. An algorithm for adaptively resizing GA populations is suggested. This algorithm is based on recent theoretical developments that relate population size to schema fitness variance. The suggested algorithm is developed theoretically, and simulated with expected value equations. The algorithm is then tested on a problem where population sizing can mislead the GA. The work presented suggests that the population sizing algorithm may be a viable way to eliminate the population sizing decision from the application of GA's.

Toward the year 2000.

PubMed

1973-12-01

If the world population continues to grow at its present rate, in only about 35 more years there will be an additional 3.5 billion people. Although it is likely that the growth rate will slow down in the future, there will be an increase of between 2.3-3.5 billion people by the year 2000. At that time the Asian, African, and Latin American regions of the world will account for between 81-84% of world population, regardless of whether there is a fertility decline. Simultaneously, the populations of Europe and North America will decrease from 26 to between 16-19%. The People's Republic of China is now working to contain population increase, but despite the efforts for every 10 Chinese alive in 1970 there will be 15 in the year 2000. For the other 9 most populous less developed countries, there will be nearly 20 persons for every 10. As this figure is 12 in the year 2000 for every 10 Russians or Americans in 1970, a significant reduction in the growth rate of population in the 10 largest less developed countries would do much to reduce the world's population problems. The number of children born between now and the year 2000 depends on the fertility of all women in the childbearing ages during that period. Finally, as the population of the world continues to increase, there will be a marked concentration of the world's children in the poorer nations, and this will be a major problem in these developing countries.

Nematode Damage Functions: The Problems of Experimental and Sampling Error

PubMed Central

Ferris, H.

1984-01-01

The development and use of pest damage functions involves measurement and experimental errors associated with cultural, environmental, and distributional factors. Damage predictions are more valuable if considered with associated probability. Collapsing population densities into a geometric series of population classes allows a pseudo-replication removal of experimental and sampling error in damage function development. Recognition of the nature of sampling error for aggregated populations allows assessment of probability associated with the population estimate. The product of the probabilities incorporated in the damage function and in the population estimate provides a basis for risk analysis of the yield loss prediction and the ensuing management decision. PMID:19295865

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

Morrison, P.

Shifts in American population dynamics during the last two decades, a period of lower birthrates and changes in age and place distribution, reflect new attitudes toward childbearing and family orientation that will have a profound effect in the next century. Demographers project a range in population growth between 1.7 and 2.7%, with more attention being given to who has children, whether or when they have them, and the changing economic role of women. Changes in age distribution lead to shifts in demand for related public services, especially affecting the financing of schools and Social Security. Population migration from metropolitan areasmore » and from the Snow to the Sun Belt has caused urban and regional problems. Demographic changes affect redistribution programs and undermine the traditional economic and political framework for carrying out redistribution. They affect census accuracy, labor-pool quality, public dependency, problems of illegal aliens, and require local fiscal adjustments to either a shrinking or a growing population.« less

[The post-colonial theoretical approach in cultural nursing research about adapting nursing care to non-Western populations].

PubMed

Racine, Louise

2003-12-01

Providing culturally competent care to non-Western populations remains a challenge in Western pluralist societies. Limitations related to the use of cultural theories to adapt nursing care have to be acknowledged. Cultural theories erase the impact of the larger social context on non-Western populations' health. Health problems arising from social inequities have to be addressed, if culturally adapted nursing interventions, are to be designed. To this end, post-colonialist theoretical approach represents a promising avenue since it is aimed at unmasking health problems intersecting with race, ethnicity, gender, and social classes. Research endeavours are directed at integrating marginalized knowledge in nursing theorization. As well, post-colonialism, from which the concept of cultural safety is derived, is a means to enhance the quality of care offered by nurses coming from dominant ethnic group to non-Western populations.

[Spanish adaptation of the "Mobile Phone Problem Use Scale" for adolescent population].

PubMed

López-Fernández, Olatz; Honrubia-Serrano, Ma Luisa; Freixa-Blanxart, Montserrat

2012-01-01

Problematic use of the mobile telephone is an emerging phenomenon in our society, and one which particularly affects the teenage population. Knowledge from research on the problematic use of this technology is necessary, since such use can give rise to a behavioural pattern with addictive characteristics. There are hardly any scales for measuring possible problematic use of mobile phones, and none at all adapted exclusively for the Spanish adolescent population. The scale most widely used internationally is the Mobile Phone Problem Use Scale (MPPUS). The aim of the present study is to adapt the MPPUS for use with Spanish adolescents. The Spanish version of the questionnaire was administered to a sample of 1132 adolescents aged 12 to 18. Reliability and factorial validity were comparable to those obtained in adult population, so that the measure of problematic mobile phone use in Spanish teenagers is one-dimensional. A prevalence of 14.8% of problematic users was detected.

Multi-Agent Inference in Social Networks: A Finite Population Learning Approach.

PubMed

Fan, Jianqing; Tong, Xin; Zeng, Yao

When people in a society want to make inference about some parameter, each person may want to use data collected by other people. Information (data) exchange in social networks is usually costly, so to make reliable statistical decisions, people need to trade off the benefits and costs of information acquisition. Conflicts of interests and coordination problems will arise in the process. Classical statistics does not consider people's incentives and interactions in the data collection process. To address this imperfection, this work explores multi-agent Bayesian inference problems with a game theoretic social network model. Motivated by our interest in aggregate inference at the societal level, we propose a new concept, finite population learning , to address whether with high probability, a large fraction of people in a given finite population network can make "good" inference. Serving as a foundation, this concept enables us to study the long run trend of aggregate inference quality as population grows.

Sustainable development: a regional perspective.

PubMed

Icamina, P

1988-12-01

This article discusses sustainable development in Asia and current environmental problems in this region. Droughts and rainy seasons pose a major concern indicating environmental limitations: India's 1987 drought halted world grain production and China suffered US $435 million in flooding damage. Deforestation and land degradation are consequences of a rising population's demand for agriculture, fuelwood, irrigation, and hydroelectric projects; 1815 million hectares of forest are cleared/year and 40% of the land could possible be subjected to soil erosion. Although population growth is declining in some Asian countries, the continent inhabits the greatest proportion of world population; 300 million are underfed. Food production remains a problem for this region because of bad weather, highly populated areas, less cropland, soil erosion, and limited water supply. Efforts currently employed to conserve natural resources include community reforestation, providing available drinking water, substituting firewood for fuelwood, and delivering primary health care.

[Biodiversity and evolution of circulating bacteria and virus populations. Novel problems of medical microbiology].

PubMed

Zhebrun, A V; Mukomolov, S L; Narvskaia, O V; Tseneva, G Ia; Kaftyreva, L A; Mokrousov, I V

2011-01-01

Biodiversity and evolution of circulating bacteria and virus populations is a serious scientific problem, solving this problem is necessary for effective prophylaxis of infectious diseases. Principal trends of development in this field of science are described. Results of studies that were carried out and investigated biodiversity of principal pathogens in Russia and St. Petersburg in particular are presented. Risk of infectious security of society caused by increasing diversity of pathogenic microorganisms is described, and priority trends of research development in this field are specified.

The health of populations living in the indigenous minority settlements of northern Yakutia.

PubMed

Burtseva, Tatiana E; Uvarova, Tatiana E; Tomsky, Mikhail I; Odland, Jon Ø

2014-01-01

This monograph contains the results of a study carried out by the Yakutsk Research Center for Complex Medical Problems, "Evaluating the health of the indigenous minorities of the Sakha Republic (Yakutia) and optimizing medical assistance using innovative technologies and telemedicine in indigenous settlements." The child population was studied in 19 indigenous minority settlements, and the adult population was studied in 12 settlements.

Problems of Definition in Locating Rural-Urban Population in Sparse Land Areas or Maximum Feasible Misunderstanding Arising from Census Data.

ERIC Educational Resources Information Center

Kraenzel, Carl F.

Rural demographic characteristics, regional distribution, and their respective trends should constitute significant policy information for the nation, but the U.S. Population Census offers little aid to the researcher studying population on a minor civil division (MCD) basis. When some census data are based on a 15 percent sample, some on a 5…

Mathematical properties and bounds on haplotyping populations by pure parsimony.

PubMed

Wang, I-Lin; Chang, Chia-Yuan

2011-06-01

Although the haplotype data can be used to analyze the function of DNA, due to the significant efforts required in collecting the haplotype data, usually the genotype data is collected and then the population haplotype inference (PHI) problem is solved to infer haplotype data from genotype data for a population. This paper investigates the PHI problem based on the pure parsimony criterion (HIPP), which seeks the minimum number of distinct haplotypes to infer a given genotype data. We analyze the mathematical structure and properties for the HIPP problem, propose techniques to reduce the given genotype data into an equivalent one of much smaller size, and analyze the relations of genotype data using a compatible graph. Based on the mathematical properties in the compatible graph, we propose a maximal clique heuristic to obtain an upper bound, and a new polynomial-sized integer linear programming formulation to obtain a lower bound for the HIPP problem. Copyright © 2011 Elsevier Inc. All rights reserved.

Mutation load and the extinction of large populations

NASA Astrophysics Data System (ADS)

Bernardes, A. T.

1996-02-01

In the time evolution of finite populations, the accumulation of harmful mutations in further generations might lead to a temporal decay in the mean fitness of the whole population that, after sufficient time, would reduce population size and so lead to extinction. This joint action of mutation load and population reduction is called Mutational Meltdown and is usually considered only to occur in small asexual or very small sexual populations. However, the problem of extinction cannot be discussed in a proper way if one previously assumes the existence of an equilibrium state, as initially discussed in this paper. By performing simulations in a genetically inspired model for time-changing populations, we show that mutational meltdown also occurs in large asexual populations and that the mean time to extinction is a nonmonotonic function of the selection coefficient. The stochasticity of the extinction process is also discussed. The extinction of small sexual N ∼ 700 populations is shown and our results confirm the assumption that the existence of recombination might be a powerful mechanism to avoid extinction.

[A health survey in riverine communities in Amazonas State, Brazil].

PubMed

Gama, Abel Santiago Muri; Fernandes, Tiótrefis Gomes; Parente, Rosana Cristina Pereira; Secoli, Silvia Regina

2018-02-19

Population-based health surveys are important tools for identifying disease determinants, especially in regions with widely dispersed populations and low health system coverage. The aim of this study was to describe the principal methodological aspects and to describe the socioeconomic, demographic, and health characteristics of the riverine populations of Coari, Amazonas State, Brazil. This was a population-based cross-sectional study in river-dwelling communities in the rural area of Coari, from April to July 2015. The probabilistic cluster sample consisted of 492 individuals. The results showed that the majority of the river-dwellers were females (53%), had up to 9 years of schooling (68.5%), and earned a monthly family income equivalent to one-third the minimum wage. The health problems reported in the previous 30 days featured conditions involving pain (45.2%). The main healthcare resources were allopathic medicines (70.3%), exceeding herbal remedies (44.3%). The river-dwellers travel an average of 60.4km and take some 4.2 hours to reach the urban area of Coari. The riverine population generally presents low economic status and limited access to the urban area. Health problems are mostly solved with allopathic medicines. Geographic characteristics, as barriers to access to health services and to improvements in living conditions for the riverine population, can limit the collection of epidemiological data on these populations.

A Descriptive Study of Gambling Among Emerging Adult Males in French-Speaking Switzerland.

PubMed

Tomei, Alexander; Tichelli, Emmanuel; Ewering, Neil; Nunweiler-Hardegger, Sophie; Simon, Olivier

2015-09-01

The aims were twofold: to examine the gambling habits of emerging adult males in the French-speaking regions of Switzerland and to what extent these habits predict problem gambling within this population. We also evaluated problem gambling rates and provided data concerning variables such as gambling location, level of information about problem gambling and awareness of treatment centers. 606 Swiss male conscripts, aged 18-22 years, completed a self-report questionnaire. This was administered during their army recruitment day in 2012. Problem gambling was assessed through the Problem Gambling Severity Index (PGSI) (Ferris and Wynne 2001). 78.5% of the respondents were lifetime gamblers, 56.1% were past-year gamblers. Four out of ten past-year gamblers played in private spaces and in back rooms. The PGSI indicated that 10.8% of past-year gamblers presented with moderate gambling problems, whilst 1.4% appeared to be problem gamblers. The majority of respondents had never received information about problem gambling. Moreover, they were unaware of the existence of treatment centers for problem gambling in their region. PGSI scores were significantly predicted by the variety of games played. Problem gambling rates among young men appear to be higher than those of the general Swiss population. This confirms that emerging adult males are a particularly vulnerable population with regards to gambling addiction. The implications of this are considered for youth gambling-prevention programs.

Health and morbidity among Bedouin women in southern Israel: a descriptive literature review of the past two decades.

PubMed

Treister-Goltzman, Yulia; Peleg, Roni

2014-08-01

In this paper we describe health and morbidity characteristics of Bedouin women in southern Israel, based on papers published over the past 20 years. This is a unique population whose customs, tradition, singular circumstances as a population "in transit", and underprivileged socio-economic status are reflected in mental illness, pregnancy course, perinatal morbidity and mortality rates, and acute and chronic disease. Recognition of these characteristics can help the medical team treat various health problems in this population as well as other populations with similar characteristics.

Disparities in self reported oral health problems among a young Syrian adult population.

PubMed

Alkhatib, M Nour; Gilthorpe, Mark S; McGrath, Colman

2002-12-01

To describe the prevalence of dental pain and other oral health problems among a young Syrian adult population and to identify socio-demographic factors associated with these experiences. An industrial sample of 400 men and women aged 18-34 years from Damascus, Syria. Study participants were interviewed about their experience of oral health problems in the previous year (1998). Socio-demographic information was collected. 93% (369) of the interviews were completed. The prevalence of oral health problems was high, with 96% (353) of respondents claiming that they experienced one or more problems in the previous year. Two thirds of participants (65%, 239) claimed they had dental pain in the previous year. Analysis revealed that dental pain experience was significantly associated with age and gender. Analysis considering all factors revealed that the odds of experiencing dental pain were higher amongst the younger age group (18-24 compared to 25-34 year-olds). The prevalence of oral health problems was high among the population studied. Socio-demographic variations in experience of dental pain were apparent, with young men of lower education having the greatest odds of dental pain experience in the previous year.

Games and gambling involvement among casino patrons.

PubMed

LaPlante, Debi A; Afifi, Tracie O; Shaffer, Howard J

2013-06-01

A growing literature is addressing the nature of the relationships among gambling activity, gambling involvement, and gambling-related problems. This research suggests that among the general population, compared to playing any specific game, gambling involvement is a better predictor of gambling-related problems. To date, researchers have not examined these relationships among casino patrons, a population that differs from the general population in a variety of important ways. A survey of 1160 casino patrons at two Las Vegas resort casinos allowed us to determine relationships between the games that patrons played during the 12 months before their casino visit, the games that patrons played during their casino visit, and patrons' self-perceived history of gambling-related problems. Results indicate that playing specific gambling games onsite predicted (i.e., statistically significant odds ratios ranging from .5 to 4.51) self-perceived gambling-related problems. However, after controlling for involvement, operationally defined as the number of games played during the current casino visit and self-reported gambling frequency during the past 12 months, the relationships between games and gambling-related problems disappeared or were attenuated (i.e., odds ratios no longer statistically significant). These results extend the burgeoning literature related to gambling involvement and its relationship to gambling-related problems.

Workplace mental health: developing an integrated intervention approach

PubMed Central

2014-01-01

Background Mental health problems are prevalent and costly in working populations. Workplace interventions to address common mental health problems have evolved relatively independently along three main threads or disciplinary traditions: medicine, public health, and psychology. In this Debate piece, we argue that these three threads need to be integrated to optimise the prevention of mental health problems in working populations. Discussion To realise the greatest population mental health benefits, workplace mental health intervention needs to comprehensively 1) protect mental health by reducing work–related risk factors for mental health problems; 2) promote mental health by developing the positive aspects of work as well as worker strengths and positive capacities; and 3) address mental health problems among working people regardless of cause. We outline the evidence supporting such an integrated intervention approach and consider the research agenda and policy developments needed to move towards this goal, and propose the notion of integrated workplace mental health literacy. Summary An integrated approach to workplace mental health combines the strengths of medicine, public health, and psychology, and has the potential to optimise both the prevention and management of mental health problems in the workplace. PMID:24884425

Genetics Home Reference: dihydrolipoamide dehydrogenase deficiency

MedlinePlus

... begin anytime from infancy to adulthood, is the primary symptom. The liver problems are usually associated with recurrent vomiting and ... of Ashkenazi Jewish descent. This population typically has liver disease as the primary symptom. In other populations, the prevalence of dihydrolipoamide ...

The Game of Contacts: Estimating the Social Visibility of Groups.

PubMed

Salganik, Matthew J; Mello, Maeve B; Abdo, Alexandre H; Bertoni, Neilane; Fazito, Dimitri; Bastos, Francisco I

2011-01-01

Estimating the sizes of hard-to-count populations is a challenging and important problem that occurs frequently in social science, public health, and public policy. This problem is particularly pressing in HIV/AIDS research because estimates of the sizes of the most at-risk populations-illicit drug users, men who have sex with men, and sex workers-are needed for designing, evaluating, and funding programs to curb the spread of the disease. A promising new approach in this area is the network scale-up method, which uses information about the personal networks of respondents to make population size estimates. However, if the target population has low social visibility, as is likely to be the case in HIV/AIDS research, scale-up estimates will be too low. In this paper we develop a game-like activity that we call the game of contacts in order to estimate the social visibility of groups, and report results from a study of heavy drug users in Curitiba, Brazil (n = 294). The game produced estimates of social visibility that were consistent with qualitative expectations but of surprising magnitude. Further, a number of checks suggest that the data are high-quality. While motivated by the specific problem of population size estimation, our method could be used by researchers more broadly and adds to long-standing efforts to combine the richness of social network analysis with the power and scale of sample surveys.

Density dependence and climate effects in Rocky Mountain elk: an application of regression with instrumental variables for population time series with sampling error.

PubMed

Creel, Scott; Creel, Michael

2009-11-01

1. Sampling error in annual estimates of population size creates two widely recognized problems for the analysis of population growth. First, if sampling error is mistakenly treated as process error, one obtains inflated estimates of the variation in true population trajectories (Staples, Taper & Dennis 2004). Second, treating sampling error as process error is thought to overestimate the importance of density dependence in population growth (Viljugrein et al. 2005; Dennis et al. 2006). 2. In ecology, state-space models are used to account for sampling error when estimating the effects of density and other variables on population growth (Staples et al. 2004; Dennis et al. 2006). In econometrics, regression with instrumental variables is a well-established method that addresses the problem of correlation between regressors and the error term, but requires fewer assumptions than state-space models (Davidson & MacKinnon 1993; Cameron & Trivedi 2005). 3. We used instrumental variables to account for sampling error and fit a generalized linear model to 472 annual observations of population size for 35 Elk Management Units in Montana, from 1928 to 2004. We compared this model with state-space models fit with the likelihood function of Dennis et al. (2006). We discuss the general advantages and disadvantages of each method. Briefly, regression with instrumental variables is valid with fewer distributional assumptions, but state-space models are more efficient when their distributional assumptions are met. 4. Both methods found that population growth was negatively related to population density and winter snow accumulation. Summer rainfall and wolf (Canis lupus) presence had much weaker effects on elk (Cervus elaphus) dynamics [though limitation by wolves is strong in some elk populations with well-established wolf populations (Creel et al. 2007; Creel & Christianson 2008)]. 5. Coupled with predictions for Montana from global and regional climate models, our results predict a substantial reduction in the limiting effect of snow accumulation on Montana elk populations in the coming decades. If other limiting factors do not operate with greater force, population growth rates would increase substantially.

Genetic differentiation among populations of marine algae

NASA Astrophysics Data System (ADS)

Innes, D. J.

1984-09-01

Most of the information for genetic differentiation among populations of marine algae is from studies on ecotypic variation. Physiological ecotypes have been described for individuals showing different responses to temperature and salinity conditions. Morphological ecotypes have also been found associated with areas differing in wave exposure or different intertidal positions. Little is known on how genetic variation is organized within and between populations of marine algae. The occurrence of ecotypic variation in some species is evidence for genetic differentiation among populations resulting from selection by the local environment. The rate of dispersal and subsequent gene flow will also affect the level of differentiation among populations. In species with low dispersal, differentiation can arise through chance founder events or random genetic drift. The few studies available have shown that species of algae exhibit a range of dispersal capabilities. This information can be useful for predicting the potential level of genetic differentiation among populations of these species. Crossing experiments with several species of algae have shown that populations separated by a considerable distance can be interfertile. In some cases individuals from these populations have been found to be morphologically distinct. Crosses have been used to study the genetic basis of this variation and are evidence for genetic differentiation among the populations sampled. Genetic variation of enzyme proteins detected by electrophoresis provides an additional method for measuring genetic variation within and between populations of marine algae. Electrophoretic methods have previously been used to study systematic problems in algae. However, there have been few attempts to use electrophoretic variation to study the genetic structure of populations of marine algae. This approach is outlined and includes some of the potential problems associated with interpreting electrophoretic data. Studies of electrophoretic variation in natural populations of Enteromorpha linza from Long island Sound are used as an example. This species was found to reproduce only asexually. Despite a dispersing spore stage, genetic differentiation was found on a microgeographic scale and was correlated with differences in the local environment of some of the populations. Similar studies on other species, and especially sexually reproducing species, will add to a growing understanding of the evolutionary genetics of marine algae.

Harvest and dynamics of duck populations

USGS Publications Warehouse

Sedinger, James S.; Herzog, Mark P.

2012-01-01

The role of harvest in the dynamics of waterfowl populations continues to be debated among scientists and managers. Our perception is that interested members of the public and some managers believe that harvest influences North American duck populations based on calls for more conservative harvest regulations. A recent review of harvest and population dynamics of North American mallard (Anas platyrhynchos) populations (Pöysä et al. 2004) reached similar conclusions. Because of the importance of this issue, we reviewed the evidence for an impact of harvest on duck populations. Our understanding of the effects of harvest is limited because harvest effects are typically confounded with those of population density; regulations are typically most liberal when populations are greatest. This problem also exists in the current Adaptive Harvest Management Program (Conn and Kendall 2004). Consequently, even where harvest appears additive to other mortality, this may be an artifact of ignoring effects of population density. Overall, we found no compelling evidence for strong additive effects of harvest on survival in duck populations that could not be explained by other factors.

Clinical management of the most common group A β-hemolytic streptococcal infections.

PubMed

Kaplan, Edward L

2013-01-01

Group A streptococcal (Streptococcus pyogenes) infections remain important causes of medical and public health morbidity and mortality even during the early twenty-first century. Although most often concentrated in socially/economically disadvantaged populations, the problems remain significant in both industrializing and industrialized countries. The many M/emm types of GAS contribute to herd immunity in populations and also affect the control of streptococcal infections in these populations. Although this bacterium remains among the most susceptible to most antibiotics, it is evident that antibiotics alone have not solved the group A streptococcal medical and public health problems, even in those places where access to medical care is readily available. It is likely that the current streptococcal problems will remain difficult to manage and will remain essentially unchanged until the broad implementation of a cost-effective group A streptococcal vaccine, likely some years in the future.

Stable or improved health status in the population 65 years and older in Stockholm, Sweden - an 8-year follow-up of self-reported health items.

PubMed

Modig, Karin; Virtanen, Suvi; Ahlbom, Anders; Agahi, Neda

2016-07-01

Previous studies have reached different conclusions about whether health is improving in the ageing population. More studies with narrow age groups analyzed separately for men and women will contribute to the literature. To describe trends in self-reported indicators of health and health-related quality of life between 2002 and 2010, focusing on differences between gender and age groups. A population-based survey of individuals 65+ in the Stockholm County was used. Prevalence of health problems increased with age both among men and women. Men generally reported having no health problems to a larger extent than women, but the proportions reporting severe problems were similar. The larger picture is one of stability in health-related quality of life, even if several items developed for the better, especially among women. While the proportions reporting no health/functional problems increased for many items, the proportions reporting severe problems remained unchanged among men and improved only for two items among women. CONCLUSIONS OVERALL, IMPROVEMENTS WERE SEEN IN MANY OF THE HEALTH-RELATED QUALITY OF LIFE ITEMS AS WELL AS FOR SELF-RATED HEALTH AMONG WOMEN THE PROPORTIONS REPORTING LONG-TERM ILLNESS OR PERSISTENT HEALTH PROBLEMS INCREASED, BUT FEWER SEEM TO BE LIMITED IN THEIR DAILY ACTIVITIES BY THESE PROBLEMS THE STABLE PROPORTIONS OF POOR SELF-RATED HEALTH INDICATES THAT WHILE HEALTH AND FUNCTIONING SEEM TO BE IMPROVING FOR THE MAJORITY OF THE OLDER POPULATION, SOME GROUPS MAY BE LAGGING BEHIND FUTURE STUDIES SHOULD PAY ATTENTION TO CHANGES BOTH IN THE UPPER AND LOWER ENDS OF THE HEALTH SPECTRUM. © 2016 the Nordic Societies of Public Health.

The health of populations living in the indigenous minority settlements of northern Yakutia

PubMed Central

Burtseva, Tatiana E.; Uvarova, Tatiana E.; Tomsky, Mikhail I.; Odland, Jon Ø.

2014-01-01

This monograph contains the results of a study carried out by the Yakutsk Research Center for Complex Medical Problems, “Evaluating the health of the indigenous minorities of the Sakha Republic (Yakutia) and optimizing medical assistance using innovative technologies and telemedicine in indigenous settlements.” The child population was studied in 19 indigenous minority settlements, and the adult population was studied in 12 settlements. PMID:25405106

Dementia Research: Populations, Progress, Problems, and Predictions.

PubMed

Hunter, Sally; Smailagic, Nadja; Brayne, Carol

2018-05-16

Alzheimer's disease (AD) is a clinicopathologically defined syndrome leading to cognitive impairment. Following the recent failures of amyloid-based randomized controlled trials to change the course of AD, there are growing calls for a re-evaluation of basic AD research. Epidemiology offers one approach to integrating the available evidence. Here we examine relationships between evidence from population-based, clinicopathological studies of brain aging and a range of hypotheses from all areas of AD research. We identify various problems, including a lack of systematic approach to measurement of clinical and neuropathological factors associated with dementia in experimental and clinical settings, poor understanding of the strengths and weaknesses of different observational and experimental designs, a lack of clarity in relation to disease definitions from the clinical, neuropathological, and molecular perspectives, inadequate characterization of brain aging in the human population, difficulties in translation between laboratory-based and population-based evidence bases, and a lack of communication between different sections of the dementia research community. Population studies highlight complexity and predict that therapeutic approaches based on single disease features will not be successful. Better characterization of brain aging in the human population is urgently required to select biomarkers and therapeutic targets that are meaningful to human disease. The generation of detailed and reliable evidence must be addressed before progress toward therapeutic interventions can be made.

Bucharest: poverty or population?

PubMed

1974-01-01

The controversy that occurred in Bucharest over the World Population Plan of Action had not been totally anticipated. Prior to the Conference, there appeared to be a general consensus that population growth was the crucial issue although it was recognized that population growth had to be considered in the context of socioeconomic and cultural development. What developed at Bucharest was a clear division between the developed countries who favored population control and implementation of family planning programs by 1986 and the developing countries who rejected the idea of population control unless it was associated with the redistribution of world resources. The reality of people having large families because they are poor cannot be denied, but, simultaneously, the problem of increasing numbers and their impact on the quality of life, nutrition, housing, education, and employment must be faced. Since affluent countries cannot be relied upon concerning the redistribution of their wealth, developing countries can bring about some change by redistributing the wealth within their countries. Adult literacy programs have been identified as a means to promote socioeconomic development, but these programs will only prove successful if they involve the adults in the process of learning by means of problem solving and cause them to reflect on their socioeconomic situation with the result of reinvolving themselves in society in order to change it.

Discrimination of fish populations using parasites: Random Forests on a 'predictable' host-parasite system.

PubMed

Pérez-Del-Olmo, A; Montero, F E; Fernández, M; Barrett, J; Raga, J A; Kostadinova, A

2010-10-01

We address the effect of spatial scale and temporal variation on model generality when forming predictive models for fish assignment using a new data mining approach, Random Forests (RF), to variable biological markers (parasite community data). Models were implemented for a fish host-parasite system sampled along the Mediterranean and Atlantic coasts of Spain and were validated using independent datasets. We considered 2 basic classification problems in evaluating the importance of variations in parasite infracommunities for assignment of individual fish to their populations of origin: multiclass (2-5 population models, using 2 seasonal replicates from each of the populations) and 2-class task (using 4 seasonal replicates from 1 Atlantic and 1 Mediterranean population each). The main results are that (i) RF are well suited for multiclass population assignment using parasite communities in non-migratory fish; (ii) RF provide an efficient means for model cross-validation on the baseline data and this allows sample size limitations in parasite tag studies to be tackled effectively; (iii) the performance of RF is dependent on the complexity and spatial extent/configuration of the problem; and (iv) the development of predictive models is strongly influenced by seasonal change and this stresses the importance of both temporal replication and model validation in parasite tagging studies.

Patient safety is not enough: targeting quality improvements to optimize the health of the population.

PubMed

Woolf, Steven H

2004-01-06

Ensuring patient safety is essential for better health care, but preoccupation with niches of medicine, such as patient safety, can inadvertently compromise outcomes if it distracts from other problems that pose a greater threat to health. The greatest benefit for the population comes from a comprehensive view of population needs and making improvements in proportion with their potential effect on public health; anything less subjects an excess of people to morbidity and death. Patient safety, in context, is a subset of health problems affecting Americans. Safety is a subcategory of medical errors, which also includes mistakes in health promotion and chronic disease management that cost lives but do not affect "safety." These errors are a subset of lapses in quality, which result not only from errors but also from systemic problems, such as lack of access, inequity, and flawed system designs. Lapses in quality are a subset of deficient caring, which encompasses gaps in therapeutics, respect, and compassion that are undetected by normative quality indicators. These larger problems arguably cost hundreds of thousands more lives than do lapses in safety, and the system redesigns to correct them should receive proportionately greater emphasis. Ensuring such rational prioritization requires policy and medical leaders to eschew parochialism and take a global perspective in gauging health problems. The public's well-being requires policymakers to view the system as a whole and consider the potential effect on overall population health when prioritizing care improvements and system redesigns.

Evaluation of the genetic structure of sika deer (Cervus nippon) in Japan's Kanto and Tanzawa mountain areas, based on microsatellite markers.

PubMed

Konishi, Sayaka; Hata, Shoko; Matsuda, Sayumi; Arai, Kazushi; Mizoguchi, Yasushi

2017-11-01

The browsing habits of sika deer (Cervus nippon) in Japan have caused serious ecological problems. Appropriate management of sika deer populations requires understanding the different genetic structures of local populations. In the present study, we used 10 microsatellite polymorphisms to explore the genetic structures of sika deer populations (162 individuals) living in the Kanto region. The expected heterozygosity of the Tanzawa mountain range population (Group I) was lower than that of the populations in the Kanto mountain areas (Group II). Our results suggest that moderate gene flow has occurred between the sika deer populations in the Kanto mountain areas (Group II), but not to or from the Tanzawa mountain range population (Group I). Also, genetic structure analysis showed that the Tanzawa population was separated from the other populations. This is probably attributable to a genetic bottleneck that developed in the Tanzawa sika deer population in the 1950s. However, we found that the Tanzawa population has since recovered from the bottleneck situation and now exhibits good genetic diversity. Our results show that it is essential to periodically evaluate the genetic structures of deer populations to develop conservation strategies appropriate to the specific structures of individual populations at any given time. © 2017 Japanese Society of Animal Science.

Purdah and overpopulation in the Middle East.

PubMed

Misch, A

1990-01-01

The Middle East and North Africa constitute the Islamic world. From Morocco to Afghanistan the population is 340 million and growing at a rate of 3% annually and will double in 23 years. Currently food, water, and land resources are being taxed to their limit and continued growth will only cause larger scale problems for the region. To complicate the issue public policies and private practices and attitudes are leading to continued population growth. The rise of Islamic fundamentalism does not recognize the problem of over population. In fact the revision of family law by fundamentalist politicians has done a great deal of damage to the improvements in the status of women throughout the region. The revival of Purdah, the practice of keeping women out of the public eye and confined to home, is just one example or how the rise of Islamic fundamentalism is turning back the clock in terms of women's rights. The primary disadvantage is that since women are being returned to the home, their only source of values is as child bearers. Women cloistered at home are expected to be prolific child bearers, in fact their value as human beings is judged primarily on this basis. It is their ability to bear sons that is coveted. This of course will only compound the population problems being experienced in the region. Few countries have tried to institute state wide family planning programs, namely: Algeria, Egypt, Morocco, Tunisia and Yemen, but none of these programs has been very successful. In Iraq, Kuwait, Oman and Saudi Arabia, population growth is viewed as a positive event because it will help eliminate the need for foreign workers. Even in this region, educated people have a lower fertility rate. For example in Jordan 60% of illiterate males "did not believe in" contraception while only 15% of men educated past the secondary level felt the same way. If women are forced out of the labor force and into the home to have children, the population problem will only grow.

Gender Bias: Roadblock to Sustainable Development.

ERIC Educational Resources Information Center

Jacobson, Jodi L.

1993-01-01

Suggests that the problems of social justice, particularly related to the status of women, are closely associated with worldwide population issues, especially in the developing world. Ties gender bias to poverty, rapid population growth, and environmental degradation in government policy perpetuated cycles. (MCO)

Iodine Deficiency

MedlinePlus

... public health problem globally. Approximately 40% of the world’s population remains at risk for iodine deficiency. Iodine Deficiency ... common preventable cause of intellectual disabilities in the world. Even mild iodine ... deficiency is seen in an entire population, it is best managed by ensuring that common ...

[Research on ecological population capacity based on food and water in Shandong province].

PubMed

Lin, C

1991-02-01

The population carrying capacity in Shandong Province, China, based on current food production and water supply is discusses. In 1988, the staple food production exceeded the amount needed for the minimum subsistence level of 300 kg/person. But if the food supply were to be kept at 500 kilos/person, the amount considered to be abundant, the province had a surplus population of 16.11 million. Based on a population projection of medium scenario, the projected level of food production would meet the needs for adequate food consumption. But if the level of abundant supply were to be kept, there would be 12.4 million surplus population. The shortage of water supply is a more acute problem. On the basis of the current water consumption of 514 cubic m/person, the water supply of the province could only meet the needs of 44.9 million. But the population in the province was already 80.6 million in 1988. If the water consumption was 1000 cubic m/person, which was the consumption level of the Soviet Union, the supply can only meet the needs of 23 million population. Even if the potential water resources were fully developed, the supply can only meet the needs of 65.4 million people at the end of the century. The 92.5 million projected population at the time would far exceed the water supply capacity. The severe shortage of water supply of the province would be the most serious ecological problem. Such constraint may also have considerable impact on the sustained socioeconomic development of the province.

From blackbirds to black holes: Investigating capture-recapture methods for time domain astronomy

NASA Astrophysics Data System (ADS)

Laycock, Silas G. T.

2017-07-01

In time domain astronomy, recurrent transients present a special problem: how to infer total populations from limited observations. Monitoring observations may give a biassed view of the underlying population due to limitations on observing time, visibility and instrumental sensitivity. A similar problem exists in the life sciences, where animal populations (such as migratory birds) or disease prevalence, must be estimated from sparse and incomplete data. The class of methods termed Capture-Recapture is used to reconstruct population estimates from time-series records of encounters with the study population. This paper investigates the performance of Capture-Recapture methods in astronomy via a series of numerical simulations. The Blackbirds code simulates monitoring of populations of transients, in this case accreting binary stars (neutron star or black hole accreting from a stellar companion) under a range of observing strategies. We first generate realistic light-curves for populations of binaries with contrasting orbital period distributions. These models are then randomly sampled at observing cadences typical of existing and planned monitoring surveys. The classical capture-recapture methods, Lincoln-Peterson, Schnabel estimators, related techniques, and newer methods implemented in the Rcapture package are compared. A general exponential model based on the radioactive decay law is introduced which is demonstrated to recover (at 95% confidence) the underlying population abundance and duty cycle, in a fraction of the observing visits (10-50%) required to discover all the sources in the simulation. Capture-Recapture is a promising addition to the toolbox of time domain astronomy, and methods implemented in R by the biostats community can be readily called from within python.

Population density and youth antisocial behavior.

PubMed

Harden, K Paige; D'Onofrio, Brian M; Van Hulle, Carol; Turkheimer, Eric; Rodgers, Joseph L; Waldman, Irwin D; Lahey, Benjamin B

2009-08-01

Theoretical models concerning how neighborhood contexts adversely influence juvenile antisocial behavior frequently focus on urban neighborhoods; however, previous studies comparing urban and rural areas on the prevalence of youth antisocial behavior have yielded mixed results. The current study uses longitudinal data on the offspring of a nationally representative sample of mothers (N = 4,886) in the US. There was no relation between density and mother-reported child conduct problems across ages 4-13 years, but youth living in areas of greater population density exhibited more youth self-reported delinquency across 10-17 years. Families often moved to counties with greater or lesser population density, but longitudinal analyses treating population density as a time-varying covariate did not support the hypothesis that living in densely populated counties influenced youth delinquency. Rather, the association between population density and delinquency appears to be due to unmeasured selection variables that differ between families who live in more or less densely populated counties.

Population Analysis: Communicating in Context

NASA Technical Reports Server (NTRS)

Rajulu, Sudhakar; Thaxton, Sherry

2008-01-01

Providing accommodation to a widely varying user population presents a challenge to engineers and designers. It is often even difficult to quantify who is accommodated and who is not accommodated by designs, especially for equipment with multiple critical anthropometric dimensions. An approach to communicating levels of accommodation referred to as population analysis applies existing human factors techniques in novel ways. This paper discusses the definition of population analysis as well as major applications and case studies. The major applications of population analysis consist of providing accommodation information for multivariate problems and enhancing the value of feedback from human-in-the-loop testing. The results of these analyses range from the provision of specific accommodation percentages of the user population to recommendations of design specifications based on quantitative data. Such feedback is invaluable to designers and results in the design of products that accommodate the intended user population.

A paradigm shift in regulating and running nursing homes in Singapore.

PubMed

Wong, Gabriel H Z; Pang, Weng Sun; Yap, Philip

2014-06-01

Singapore faces a rapidly aging population. By 2030, 19% of her population will be aged 65 years and above. Other Asian countries face similar problems, with South Korea having the fastest aging population worldwide, followed by China and Thailand. With Singapore possessing an advanced aging population, its policy provides a useful case study of eldercare to cater to evolving population demographics. This article will focus specifically on nursing homes and analyze current policies toward them, synthesize recommendations to improve long-term care, and justify a paradigm shift toward more holistic, humanistic, and multidimensional care. Copyright © 2014 American Medical Directors Association, Inc. Published by Elsevier Inc. All rights reserved.

Learning experiences in population education: proposed guidelines and core messages.

PubMed

1984-01-01

As a result of the 1984 Regional Workshop for the Development of Packages of Adequate Learning Requirements in Population Education, the participants tackled the problem of non-institutionalization of population education into the formal and non-formal educational curricula in their countries. Based on their deliberations, several sets of guidelines and core messages were formulated to provide countries with a more definite direction that will hopefully ensure the functional and effective integration of population education in their respective national school and out-of-school curriculum system. Useful packages of learning materials in population education should help realize the country's population policy and goals within the broader framework of socioeconomic development, and the content of the package should comprehensively cover the core messages of the country's Population Information, Education and Communication (IEC) Program. The population knowledge base of the package should be accurate and relevant; the package should provide for graphic and visual presentation and for assessment of effects on the target groups. Proposed core messages in population education discuss the advantages of small family size and delayed marriage, and aspects of responsible parenthood. Other messages discuss population resource development and population-related beliefs and values.

Neutral theory, microbial practice: challenges in bacterial population genetics.

PubMed

Rocha, Eduardo P C

2018-04-19

Kimura's outstanding contributions to population genetics included many elegant theoretical results on the vagaries of alleles in populations. Once polymorphism data showed extensive variation in natural populations, these results led naturally to the Neutral Theory. In this article, I'll depart from some of these results to focus on four major open problems in microbial population genetics with direct implications to the study of molecular evolution: the lack of neutral polymorphism, the modeling of genetic exchanges, the population genetics of ill-defined populations, and the difficulty of untangling selection and demography in the light of the previous issues. Whilst studies in population genetics usually focus on single nucleotide polymorphism and allelic recombination, ignoring even small indels, a large fraction of genetic diversification in Bacteria results from horizontal gene transfer. Ignoring this fact defeats the purpose of population genetics: to characterize the genetic variation in populations and their adaptive effects. I'll argue that, following on Kimura's life work, one may need to develop new approaches to study microbes that reproduce asexually but are able to engage in gene exchanges with very distantly related organisms in a context where random sampling is often unachievable, populations are ill-defined, genetic linkage is strong, and random drift is rare.

Resolving the multiple sequence alignment problem using biogeography-based optimization with multiple populations.

PubMed

Zemali, El-Amine; Boukra, Abdelmadjid

2015-08-01

The multiple sequence alignment (MSA) is one of the most challenging problems in bioinformatics, it involves discovering similarity between a set of protein or DNA sequences. This paper introduces a new method for the MSA problem called biogeography-based optimization with multiple populations (BBOMP). It is based on a recent metaheuristic inspired from the mathematics of biogeography named biogeography-based optimization (BBO). To improve the exploration ability of BBO, we have introduced a new concept allowing better exploration of the search space. It consists of manipulating multiple populations having each one its own parameters. These parameters are used to build up progressive alignments allowing more diversity. At each iteration, the best found solution is injected in each population. Moreover, to improve solution quality, six operators are defined. These operators are selected with a dynamic probability which changes according to the operators efficiency. In order to test proposed approach performance, we have considered a set of datasets from Balibase 2.0 and compared it with many recent algorithms such as GAPAM, MSA-GA, QEAMSA and RBT-GA. The results show that the proposed approach achieves better average score than the previously cited methods.

An optimal control strategies using vaccination and fogging in dengue fever transmission model

NASA Astrophysics Data System (ADS)

Fitria, Irma; Winarni, Pancahayani, Sigit; Subchan

2017-08-01

This paper discussed regarding a model and an optimal control problem of dengue fever transmission. We classified the model as human and vector (mosquito) population classes. For the human population, there are three subclasses, such as susceptible, infected, and resistant classes. Then, for the vector population, we divided it into wiggler, susceptible, and infected vector classes. Thus, the model consists of six dynamic equations. To minimize the number of dengue fever cases, we designed two optimal control variables in the model, the giving of fogging and vaccination. The objective function of this optimal control problem is to minimize the number of infected human population, the number of vector, and the cost of the controlling efforts. By giving the fogging optimally, the number of vector can be minimized. In this case, we considered the giving of vaccination as a control variable because it is one of the efforts that are being developed to reduce the spreading of dengue fever. We used Pontryagin Minimum Principle to solve the optimal control problem. Furthermore, the numerical simulation results are given to show the effect of the optimal control strategies in order to minimize the epidemic of dengue fever.

Seaducks: A time for action

USGS Publications Warehouse

Petersen, Margaret R.; Hogan, Mary E.; Ratti, John T.; Giudice, John H.

1996-01-01

Seaducks (Tribe Mergini) are a diverse group of birds. In North America, many species nest in boreal or arctic habitats in Canada and Alaska and winter in ice-free coastal, marine, and freshwater habitats. Data from long- term surveys, population studies, and local knowledge suggest that some populations and species of seaducks have declined over the past decades. In most cases, the trend data are sufficient to document population problems, although the precise historic population and number of remaining birds are frequently unknown. As various state, provincial, and federal agencies attempt to address this problem, the need for additional information becomes clear. In the U.S., funding for work on seaducks generally has not been available until a species has been listed or proposed for lisiting under the Endangered Species Act. It is also clear that the funding sources for waterfowl in general are inadequate to address all of the management needs for both seaducks and more heavily hunted species. However, this is not a satisfactory justification of the general neglect of seaducks. Here we discuss the problems of identifying and prioritizing studies and research of this diverse group and propose a plan of action.

Demographic and genetic status of an isolated population of bog turtles (Glyptemys muhlenbergii): Implications for managing small populations of long-lived animals

USGS Publications Warehouse

Pittman, Shannon E.; King, T.L.; Faurby, S.; Dorcas, M.E.

2011-01-01

In this study, we sought to determine the population stability and genetic diversity of one isolated population of the federally-threatened bog turtle (Glyptemys muhlenbergii) in North Carolina. Using capture-recapture data, we estimated adult survival and population growth rate from 1992 to 2007. We found that the population decreased from an estimated 36 adult turtles in 1994 to approximately 11 adult turtles in 2007. We found a constant adult survival of 0. 893 (SE = 0. 018, 95% confidence interval, 0. 853-0. 924) between 1992 and 2007. Using 18 microsatellite markers, we compared the genetic status of this population with five other bog turtle populations. The target population displayed allelic richness (4. 8 ?? 0. 5) and observed heterozygosity (0. 619 ?? 0. 064) within the range of the other bog turtle populations. Coalescent analysis of population growth rate, effective population size, and timing of population structuring event also indicated the genetics of the target population were comparable to the other populations studied. Estimates of effective population size were a proportion of the census size in all populations except the target population, in which the effective population size was larger than the census size (30 turtles vs. 11 turtles). We attribute the high genetic diversity in the target population to the presence of multiple generations of old turtles. This study illustrates that the demographic status of populations of long-lived species may not be reflected genetically if a decline occurred recently. Consequently, the genetic integrity of populations of long-lived animals experiencing rapid demographic bottlenecks may be preserved through conservation efforts effective in addressing demographic problems. ?? 2011 Springer Science+Business Media B.V.

Genetic Variation and Population Differentiation in a Medical Herb Houttuynia cordata in China Revealed by Inter-Simple Sequence Repeats (ISSRs)

PubMed Central

Wei, Lin; Wu, Xian-Jin

2012-01-01

Houttuynia cordata is an important traditional Chinese herb with unresolved genetics and taxonomy, which lead to potential problems in the conservation and utilization of the resource. Inter-simple sequence repeat (ISSR) markers were used to assess the level and distribution of genetic diversity in 226 individuals from 15 populations of H. cordata in China. ISSR analysis revealed low genetic variations within populations but high genetic differentiations among populations. This genetic structure probably mainly reflects the historical association among populations. Genetic cluster analysis showed that the basal clade is composed of populations from Southwest China, and the other populations have continuous and eastward distributions. The structure of genetic diversity in H. cordata demonstrated that this species might have survived in Southwest China during the glacial age, and subsequently experienced an eastern postglacial expansion. Based on the results of genetic analysis, it was proposed that as many as possible targeted populations for conservation be included. PMID:22942696

Genetic variation and population differentiation in a medical herb Houttuynia cordata in China revealed by inter-simple sequence repeats (ISSRs).

PubMed

Wei, Lin; Wu, Xian-Jin

2012-01-01

Houttuynia cordata is an important traditional Chinese herb with unresolved genetics and taxonomy, which lead to potential problems in the conservation and utilization of the resource. Inter-simple sequence repeat (ISSR) markers were used to assess the level and distribution of genetic diversity in 226 individuals from 15 populations of H. cordata in China. ISSR analysis revealed low genetic variations within populations but high genetic differentiations among populations. This genetic structure probably mainly reflects the historical association among populations. Genetic cluster analysis showed that the basal clade is composed of populations from Southwest China, and the other populations have continuous and eastward distributions. The structure of genetic diversity in H. cordata demonstrated that this species might have survived in Southwest China during the glacial age, and subsequently experienced an eastern postglacial expansion. Based on the results of genetic analysis, it was proposed that as many as possible targeted populations for conservation be included.

Middle East assessment.

PubMed

Mahran, M

1984-06-01

All governments of the Arab world are aware of the population issue, and there has been increasing interest in policies designed to bring about a lower rate of natural increase and older population age structure. Overpopulation is believed to be a major obstacle to economic development. The population activities of the Arab countries can be divided into 3 categories: national policy to reduce population growth; nongovernmental efforts to reduce population growth; and countries with pronatalist policies. The countries with a national policy to reduce population growth include Egypt, Tunisia, and Morocco. All suffer severe problems of high density, young age structure, and lack of balance between the population and the economy. In these countries an active national family planning program operates alongside many active nongovernmental family planning associations. Reduction of the growth rate is regarded as urgent, and emigration is encouraged. In egypt contraceptives are readily available through commerical outlets, and village level social and economic activities are promoted in conjunction with family planning services. Tunisia is the only country to offer voluntary sterilization and 1st trimester abortion on request. Morocco includes family planning in its health and welfare services and there is an active voluntary family planning association. Countries in the group who have made nongovernmental efforts to reduce population growth include Algeria, Bahrain, Iarq, Jordan, Lebanon, Sudan, Syria, and Democratic Yemen. all have major population problems and generally support reduced growth rated but as yet have no national family planning. In this group the highest rate of population increase is in Syria, 3.8% a year; the highest total fertility rate is in Bahrain with almost 8 children per women. Saudi Arabia, Kewait, Qwatar, Libya, and Oman have pronatalist policies. Methods of contraception are available in the private sector. The outstanding feature of these oil rich countries is their high per capita gross national product. A 1981 estimate showed Qatar's at US$27,790, to be the highest in the world. Generally, all the governments of the Arab world have become aware of population issues and of the population pressures within their own borders.

Perceptions of twelve-step mutual-help groups and their associations with motivation, treatment attendance and alcohol outcomes among chronically homeless individuals with alcohol problems.

PubMed

Grazioli, Véronique S; Collins, Susan E; Daeppen, Jean-Bernard; Larimer, Mary E

2015-05-01

Twelve-step mutual-help groups (TMGs) are among the most available forms of support for homeless individuals with alcohol problems. Qualitative research, however, has suggested that this population often has negative perceptions of these groups, which has been shown to be associated with low TMG attendance. It is important to understand this population's perceptions of TMGs and their association with alcohol outcomes to provide more appropriate and better tailored programming for this multiply affected population. The aims of this cross-sectional study were to (a) qualitatively examine perception of TMGs in this population and (b) quantitatively evaluate its association with motivation, treatment attendance and alcohol outcomes. Participants (N=62) were chronically homeless individuals with alcohol problems who received single-site Housing First within a larger evaluation study. Perceptions of TMGs were captured using an open-ended item. Quantitative outcome variables were created from assessments of motivation, treatment attendance and alcohol outcomes. Findings indicated that perceptions of TMGs were primarily negative followed by positive and neutral perceptions, respectively. There were significant, positive associations between perceptions of TMGs and motivation and treatment attendance, whereas no association was found for alcohol outcomes. Although some individuals view TMGs positively, alternative forms of help are needed to engage the majority of chronically homeless individuals with alcohol problems. Copyright © 2014 Elsevier B.V. All rights reserved.

Nutrition, Development, and Population Growth

ERIC Educational Resources Information Center

Berg, Alan

1973-01-01

Focuses on the problem of malnutrition in developing countries through a description of its interrelationships with human development, national economies, economic growth and income, agricultural advances, the crisis in infant feeding practices, new foods, and the population dilemma. Outlines possible future policy directions to significantly…

ASSESSING RISKS TO WILDLIFE POPULATIONS FROM MULTIPLE STRESSORS: OVERVIEW OF PROBLEM AND RESEARCH NEEDS

EPA Science Inventory

Wildlife populations are experiencing increasing pressure from human-induced changes in the landscape. Stressors including agricultural and urban land use, introduced invasive and exotic species, nutrient enrichment, direct human disturbance, and toxic chemicals directly or indi...

Substance Abuse among the Deaf Population: An Overview of Current Strategies, Programs and Barriers to Recovery.

ERIC Educational Resources Information Center

Lane, Katherine E.

1989-01-01

The paper analyzes the problem of alcohol and drug abuse among the deaf population focusing on: precipitating factors leading to substance abuse; barriers to recovery; and descriptions of several treatment centers, programs, and services. (JDD)

[A tentative discussion on population control in Hangzhou and direction of its development].

PubMed

Gu, Y

1982-07-29

Hangzhou is a city noted for its scenic beauty. In recent years, developments in industrial and agricultural production, cultural and educational improvements, and various constructions have made Hangzhou a more modernized city, and its population growth has become more rapid. According to one estimate, the number of childbearing women in 1987 will increase by 61% over the 1978 figure. With the mechanic (mobility) growth rate being higher than the natural growth rate, a large population is moving into Hangzhou each year, and the problem of overpopulation is becoming increasingly serious. The supply of newly built residences cannot match the demand, and the living standard is declining. Cultural and educational establishments, health care, and public facilities are unable to catch up with the speed of the population growth. Problems such as unemployment, traffic congestion, and environmental pollution are becoming more serious. In order to cope with the overall situation, the natural growth rate of the urban population should be controlled, and every married couple should be urged to have only 1 child. Satellite cities should be established and developed to match the city's economic development. Another necessary step is the redistribution of existing factories and industries inside the city and of the city's population so as to reduce pollution and noise. The increased labor population should receive better care in order to increase their productivity. Work in gardening and services should be encouraged in order to ease the pressure of unemployment and increase the tourist income.

JPRS Report, China.

DTIC Science & Technology

1993-02-09

Birth Control Measures [RENKOU YU JINGJI25 Oct] 37 Conference on Population Problems in Southwest [RENKOU YU JINGJI 25 Oct] -. 38 Southern JiangsU... Birth Control Measures 93CE0171A Beijing RENKOU YU JINGJI [POPULATION AND ECONOMICS] in Chinese No 74, 25 Oct 92 pp 43-45 [Article by Deng Guosheng...6772 0948 0524), affiliated with the Population Department of Jiangxi Teachers College: "More Attention Needs To Be Paid to Our Poor Birth Control Results

Operation Husky: Operational Art in Large Formation Combined Arms Maneuver

DTIC Science & Technology

2013-12-10

mountain ranges; the character, position, and shape of frontiers; density of population and consequent refugee problem; transportation means; and the...About 10 percent of the population lived scattered throughout the countryside. The majority of the population was engaged in agriculture and had a...varied from 25 feet on the coast to 15 feet in the mountains . Provincial roads were not asphalted and they varied from 10 to 19 feet in width. Finally

Contaminant effects on Great Lakes' fish-eating birds: a population perspective

USGS Publications Warehouse

Heinz, G.H.; Kendall, Ronald J.; Dickerson, Richard L.; Giesy, John P.; Suk, William P.

1998-01-01

Preventing environmental contaminants from reducing wildlife populations is the greatest concern in wildlife toxicology. In the Great Lakes, environmental contaminants have a history of reducing populations of many species of fish-eating birds. Endocrine effects may have contributed to declines in fish-eating bird populations, but the overriding harm was caused by DDE-induced eggshell thinning. Toxic effects may still be occurring today, but apparently they are not of a sufficient magnitude to depress populations of most fish-eating birds. Once DDE levels in the Great Lakes declined, eggshells of birds began to get thicker and reproductive success improved. Populations of double-crested cormorants (Phalacrocorax auritus) and ring-billed gulls (Larus delawarensis) have increased dramatically since the bans on DDT and other organochlorine pesticides. Bald eagles (Haliaeetus leucocephalus) are still not reproducing at a normal rate along the shores of the Great Lakes, but success is much improved compared to earlier records when eggshell thinning was worse. Other species, such as herring gulls (Larus argentatus) and black-crowned night-herons (Nycticorax nycticorax), seem to be having improved reproductive success, but data on Great Lakes'-wide population changes are incomplete. Reproductive success of common terns (Sterna hirundo), Caspian terns (Sterna caspia), and Forster's terns (Sterna forsteri) seems to have improved in recent years, but, again, data on population changes are not very complete, and these birds face many habitat related problems as well as contaminant problems. Although contaminants are still producing toxic effects, and these effects may include endocrine disfunction, fish-eating birds in the Great Lakes seem to be largely weathering these effects, at least as far as populations are concerned. A lack of obvious contaminant effects on populations of fish-eating birds in the Great Lakes, however, should not be equated with a lack of any harm to these birds or with a conclusion that certain contaminants do not need additional control.

Parameter as a Switch Between Dynamical States of a Network in Population Decoding.

PubMed

Yu, Jiali; Mao, Hua; Yi, Zhang

2017-04-01

Population coding is a method to represent stimuli using the collective activities of a number of neurons. Nevertheless, it is difficult to extract information from these population codes with the noise inherent in neuronal responses. Moreover, it is a challenge to identify the right parameter of the decoding model, which plays a key role for convergence. To address the problem, a population decoding model is proposed for parameter selection. Our method successfully identified the key conditions for a nonzero continuous attractor. Both the theoretical analysis and the application studies demonstrate the correctness and effectiveness of this strategy.

Research progress of plant population genomics based on high-throughput sequencing.

PubMed

Wang, Yun-sheng

2016-08-01

Population genomics, a new paradigm for population genetics, combine the concepts and techniques of genomics with the theoretical system of population genetics and improve our understanding of microevolution through identification of site-specific effect and genome-wide effects using genome-wide polymorphic sites genotypeing. With the appearance and improvement of the next generation high-throughput sequencing technology, the numbers of plant species with complete genome sequences increased rapidly and large scale resequencing has also been carried out in recent years. Parallel sequencing has also been done in some plant species without complete genome sequences. These studies have greatly promoted the development of population genomics and deepened our understanding of the genetic diversity, level of linking disequilibium, selection effect, demographical history and molecular mechanism of complex traits of relevant plant population at a genomic level. In this review, I briely introduced the concept and research methods of population genomics and summarized the research progress of plant population genomics based on high-throughput sequencing. I also discussed the prospect as well as existing problems of plant population genomics in order to provide references for related studies.

Insurance problems among inflammatory bowel disease patients: results of a Dutch population based study.

PubMed

Russel, M G V M; Ryan, B M; Dagnelie, P C; de Rooij, M; Sijbrandij, J; Feleus, A; Hesselink, M; Muris, J W; Stockbrugger, R

2003-03-01

The majority of patients with inflammatory bowel disease (IBD) have a normal life expectancy and therefore should not be weighted when applying for life assurance. There is scant literature on this topic. In this study our aim was to document and compare the incidence of difficulties in application for life and medical insurance in a population based cohort of IBD patients and matched population controls. A population based case control study of 1126 IBD patients and 1723 controls. Based on a detailed questionnaire, the frequency and type of difficulties encountered when applying for life and medical insurance in matched IBD and control populations were appraised. In comparison with controls, IBD patients had an 87-fold increased risk of encountering difficulties when applying for life assurance (odds ratio (OR) 87 (95% confidence interval (CI) 31-246)), with a heavily weighted premium being the most common problem. Patients of high educational status, with continuous disease activity, and who smoked had the highest odds of encountering such problems. Medical insurance difficulties were fivefold more common in IBD patients compared with controls (OR 5.4 (95% CI 2.3-13)) although no specific disease or patient characteristics were identified as associated with such difficulties. This is the first detailed case control study that has investigated insurance difficulties among IBD patients. Acquiring life and medical insurance constituted a major problem for IBD patients in this study. These results are likely to be more widely representative given that most insurance companies use international guidelines for risk assessment. In view of the recent advances in therapy and promising survival data on IBD patients, evidence based guidelines for risk assessment of IBD patients by insurance companies should be drawn up to prevent possible discriminatory practices.

Insurance problems among inflammatory bowel disease patients: results of a Dutch population based study

PubMed Central

Russel, M G V M; Ryan, B M; Dagnelie, P C; de Rooij, M; Sijbrandij, J; Feleus, A; Hesselink, M; Muris, J W; Stockbrugger, R

2003-01-01

Background and aims: The majority of patients with inflammatory bowel disease (IBD) have a normal life expectancy and therefore should not be weighted when applying for life assurance. There is scant literature on this topic. In this study our aim was to document and compare the incidence of difficulties in application for life and medical insurance in a population based cohort of IBD patients and matched population controls. Methods: A population based case control study of 1126 IBD patients and 1723 controls. Based on a detailed questionnaire, the frequency and type of difficulties encountered when applying for life and medical insurance in matched IBD and control populations were appraised. Results: In comparison with controls, IBD patients had an 87-fold increased risk of encountering difficulties when applying for life assurance (odds ratio (OR) 87 (95% confidence interval (CI) 31–246)), with a heavily weighted premium being the most common problem. Patients of high educational status, with continuous disease activity, and who smoked had the highest odds of encountering such problems. Medical insurance difficulties were fivefold more common in IBD patients compared with controls (OR 5.4 (95% CI 2.3–13)) although no specific disease or patient characteristics were identified as associated with such difficulties. Conclusions: This is the first detailed case control study that has investigated insurance difficulties among IBD patients. Acquiring life and medical insurance constituted a major problem for IBD patients in this study. These results are likely to be more widely representative given that most insurance companies use international guidelines for risk assessment. In view of the recent advances in therapy and promising survival data on IBD patients, evidence based guidelines for risk assessment of IBD patients by insurance companies should be drawn up to prevent possible discriminatory practices. PMID:12584216

Mental health in the Dutch population and in general practice: 1987–2001

PubMed Central

Verhaak, Peter FM; Hoeymans, Nancy; Garssen, Anna A; Westert, Gert P

2005-01-01

Background In the last 15 years, both the demand for and supply of specialised mental health care increased considerably in the Netherlands. Increased demand may reflect a change in psychological morbidity, but may also be a consequence of increased supply. Specialised health care in the Netherlands is accessible only through referral by a GP, and so it is important to consider the role of primary care in the diagnosis of mental health problems. Aim The aim of this study is to achieve a better understanding of the development of mental health status in the Dutch population and the consequent help-seeking behaviour in primary care. Method Using two comparable morbidity studies carried out in the Dutch population and in primary care, we compared data from 1987 and 2001 to assess the following: possible differences in mental health between 1987 and 2001; possible differences in prevalence of mental disorder as diagnosed by GPs in 1987 and 2001; possible differences in the sociodemographic determinants of mental health and mental disorder in primary care between 1987 and 2001. Results Our results show an increase in mental and social problems in the population between 1987 and 2001. However, GPs diagnosed fewer patients as having a mental disorder in 2001 than they did in 1987. The risk of mental disorders or social problems in several sociodemographic groups remained largely the same, as did the chance of receiving a psychological or social diagnosis. Conclusion We conclude that, while mental disorder in the population is increasing, the role of primary care has changed. Although GPs diagnose a lower percentage of mental problems as such, they refer an increasingly larger proportion of these to secondary care. PMID:16212852

Population growth and development in the Third World: the neocolonial context.

PubMed

Patterson, J G; Shrestha, N R

1988-01-01

Less developed countries (LDCs) that were colonies of other nations continued operating under the same social and political structures set up by the former ruling nations. The small minority of elites in the LDCs held on to the power acquired during colonial times. In order to preserve their political and financial status after independence, they maintained their close linkages to the capitalist nations and their multinational corporations (MNCs). The elites did not generally have popular support, however. These capitalist nations and their commercial interests continue to dictate most LDCs development process which supports the financial interests of the MNCs and the local elites and not those of the majority, the poor. The poor realize that they are trapped and unable to break away from the economic and political structures, therefore, to assure some form of security, they have many children which exacerbates their poverty. Yet population control policies based on Malthusian theory and those that rely on such undimensional, technical approaches as family planning alone cannot cure the multidimensional social problems of high population growth and poverty. Neither the Malthusian nor Marxist theories totally explain the situation in the LDCs or even provide workable solutions. Research on population and development in LDCs needs to address both the Malthusian concern for the problems posed by high growth rates and the Marxist critique of class struggle in development trends. To eliminate the trap of poverty and dependent economies, each country must design its own remedies based on its history, culture, and geography and alter the prevailing social, economic, and political power structures in favor of the poor. 6 propositions that must be modified to each nation's particular problems and needs are presented to guide LDCs in formulating or reformulating policies to alleviate the problems of population and poverty.

Europe in the energy transition: the case for a smaller population.

PubMed

Grant, L

1988-07-01

Europe has not yet reached a sustainable society, that is, like the rest of the world, its people cannot live comfortably within its resources, but, it has achieved stabilizing population growth, a control on a potentially dangerous dependency on imported food, an adjustment to the transition from the colonial era, and a position conducive to deal with the energy transition. Europe is the most densely population region of the world, except for Japan. Concern about depopulation in western Europe is misplaced because European populations are on a plateau not a decline, and a lower population is a benefit when confronting resource and environmental constraints. World oil production is expected to peak and then to decline depending on demand, prices, and technology. European oil production will decline, and the United Kingdom will become a net importer in the mid-1990s. The environmental transition is described as more complex than finding a substitute for oil, in part because Europe, unlike the US, has limited fossil fuel resources which are also less accessible. Biomass as the alternative to fossil fuels must be produced on lands currently in food or forestry production. Also corn and bagasse production is not suited to for growing the European climate. Nuclear energy, with its safety and disposal problems, is only an interim solution. Hydropower development is expensive, and solar power is unsuitable because of the continual cloud cover. Wind power is possible but expensive at low wind levels, and the whole of western Europe is relatively unsuitable. Capital creates wealth, and unemployment is Europe's present problem. Large populations in the current technological revolution do not create greater wealth or military security. Europe and Japan have arrived at the population/energy/environment problem first, and many questions remain as to how to manage the age structure, how to maintain innovation and creativity, and how to maintain a prosperous steady state economy.

Population pressure, poverty and the environment.

PubMed

Camp, S L

1992-06-01

Using the agricultural revolution as a starting point, human population has grown 50 times since then. The amount of environmental and ecological damage inflicted by humans before the agricultural revolution pales in comparison to the damage done afterwards. It took until 1800, or approximately 9800 years from the beginning of the agricultural revolution, for world population to reach 1 billion. It took only 187 years to reach 5 billion and current projections estimate that it will take only 11 years to add the 6th billion. If the governments of the world do not work together during this decade and bring a family planning message to every couple of reproductive age, the results will be catastrophic. Every year 40-50 million acres of forest are cut down. On average, the people living in developing countries are cutting down forests twice as fast as they can grow back. Deforestation, combined with intensive agriculture, is turning the world's farm land into desert. Soil erosion and desertification threaten 1/3 of the total land surface which is home to 1/5 of the population. While high consumption levels in developed countries and industrial pollution worldwide do have a huge impact, the fact remains that increases in population place increased burdens on the ecology's carrying capacity. While the former problems urgently need to be addressed, reducing population growth rates eases pressure on all the aspects of the environment. China suffers from every kind of ecological problem and its reliance on high sulfur coal as a primary energy source threatens to undo all the efficiency improvements made in developed countries. Water shortages are common in China as they are in many other countries, again a problem that would be less severe if population growth were reduced. Urban areas are the fastest growing and least prepared to handle the increased demand for drinking water and sanitation control. The cost of universal family planning is only US$9 billion.

Sampling design considerations for demographic studies: a case of colonial seabirds

USGS Publications Warehouse

Kendall, William L.; Converse, Sarah J.; Doherty, Paul F.; Naughton, Maura B.; Anders, Angela; Hines, James E.; Flint, Elizabeth

2009-01-01

For the purposes of making many informed conservation decisions, the main goal for data collection is to assess population status and allow prediction of the consequences of candidate management actions. Reducing the bias and variance of estimates of population parameters reduces uncertainty in population status and projections, thereby reducing the overall uncertainty under which a population manager must make a decision. In capture-recapture studies, imperfect detection of individuals, unobservable life-history states, local movement outside study areas, and tag loss can cause bias or precision problems with estimates of population parameters. Furthermore, excessive disturbance to individuals during capture?recapture sampling may be of concern because disturbance may have demographic consequences. We address these problems using as an example a monitoring program for Black-footed Albatross (Phoebastria nigripes) and Laysan Albatross (Phoebastria immutabilis) nesting populations in the northwestern Hawaiian Islands. To mitigate these estimation problems, we describe a synergistic combination of sampling design and modeling approaches. Solutions include multiple capture periods per season and multistate, robust design statistical models, dead recoveries and incidental observations, telemetry and data loggers, buffer areas around study plots to neutralize the effect of local movements outside study plots, and double banding and statistical models that account for band loss. We also present a variation on the robust capture?recapture design and a corresponding statistical model that minimizes disturbance to individuals. For the albatross case study, this less invasive robust design was more time efficient and, when used in combination with a traditional robust design, reduced the standard error of detection probability by 14% with only two hours of additional effort in the field. These field techniques and associated modeling approaches are applicable to studies of most taxa being marked and in some cases have individually been applied to studies of birds, fish, herpetofauna, and mammals.

Alcohol Use-Related Problems Among a Rural Indian Population of West Bengal: An Application of the Alcohol Use Disorders Identification Test (AUDIT).

PubMed

Barik, Anamitra; Rai, Rajesh Kumar; Chowdhury, Abhijit

2016-03-01

To examine alcohol use and related problems among a rural subset of the Indian population. The Alcohol Use Disorders Identification Test (AUDIT) was used as part of Health and Demographic Surveillance of 36,611 individuals aged ≥18 years. From this survey data on 3671 current alcohol users were analysed using bivariate and multivariate ordered logit regression. Over 19% of males and 2.4% of females were current alcohol users. Mean ethanol consumption on a typical drinking day among males was estimated to be higher (96.3 gm) than females (56.5 gm). Mean AUDIT score was 11 among current alcohol users. AUDIT showed in the ordered logit regression estimated alcohol use-related problems to be low among women, Scheduled Tribes and unmarried people, whereas alcohol use-related problems registered high among Muslims. This rural population appears to be in need of an effective intervention program, perhaps targeting men and the household, aimed at reducing the level of alcohol use and related problems. © The Author 2015. Medical Council on Alcohol and Oxford University Press. All rights reserved.

SPLICER - A GENETIC ALGORITHM TOOL FOR SEARCH AND OPTIMIZATION, VERSION 1.0 (MACINTOSH VERSION)

NASA Technical Reports Server (NTRS)

Wang, L.

1994-01-01

SPLICER is a genetic algorithm tool which can be used to solve search and optimization problems. Genetic algorithms are adaptive search procedures (i.e. problem solving methods) based loosely on the processes of natural selection and Darwinian "survival of the fittest." SPLICER provides the underlying framework and structure for building a genetic algorithm application. These algorithms apply genetically-inspired operators to populations of potential solutions in an iterative fashion, creating new populations while searching for an optimal or near-optimal solution to the problem at hand. SPLICER 1.0 was created using a modular architecture that includes a Genetic Algorithm Kernel, interchangeable Representation Libraries, Fitness Modules and User Interface Libraries, and well-defined interfaces between these components. The architecture supports portability, flexibility, and extensibility. SPLICER comes with all source code and several examples. For instance, a "traveling salesperson" example searches for the minimum distance through a number of cities visiting each city only once. Stand-alone SPLICER applications can be used without any programming knowledge. However, to fully utilize SPLICER within new problem domains, familiarity with C language programming is essential. SPLICER's genetic algorithm (GA) kernel was developed independent of representation (i.e. problem encoding), fitness function or user interface type. The GA kernel comprises all functions necessary for the manipulation of populations. These functions include the creation of populations and population members, the iterative population model, fitness scaling, parent selection and sampling, and the generation of population statistics. In addition, miscellaneous functions are included in the kernel (e.g., random number generators). Different problem-encoding schemes and functions are defined and stored in interchangeable representation libraries. This allows the GA kernel to be used with any representation scheme. The SPLICER tool provides representation libraries for binary strings and for permutations. These libraries contain functions for the definition, creation, and decoding of genetic strings, as well as multiple crossover and mutation operators. Furthermore, the SPLICER tool defines the appropriate interfaces to allow users to create new representation libraries. Fitness modules are the only component of the SPLICER system a user will normally need to create or alter to solve a particular problem. Fitness functions are defined and stored in interchangeable fitness modules which must be created using C language. Within a fitness module, a user can create a fitness (or scoring) function, set the initial values for various SPLICER control parameters (e.g., population size), create a function which graphically displays the best solutions as they are found, and provide descriptive information about the problem. The tool comes with several example fitness modules, while the process of developing a fitness module is fully discussed in the accompanying documentation. The user interface is event-driven and provides graphic output in windows. SPLICER is written in Think C for Apple Macintosh computers running System 6.0.3 or later and Sun series workstations running SunOS. The UNIX version is easily ported to other UNIX platforms and requires MIT's X Window System, Version 11 Revision 4 or 5, MIT's Athena Widget Set, and the Xw Widget Set. Example executables and source code are included for each machine version. The standard distribution media for the Macintosh version is a set of three 3.5 inch Macintosh format diskettes. The standard distribution medium for the UNIX version is a .25 inch streaming magnetic tape cartridge in UNIX tar format. For the UNIX version, alternate distribution media and formats are available upon request. SPLICER was developed in 1991.

Psychometric properties of the Social Problem Solving Inventory-Revised Short-Form in a South African population.

PubMed

Sorsdahl, Katherine; Stein, Dan J; Myers, Bronwyn

2017-04-01

The Social Problem Solving Inventory-Revised Short-Form (SPSI-R:SF) has been used in several countries to identify problem-solving deficits among clinical and general populations in order to guide cognitive-behavioural interventions. Yet, very few studies have evaluated its psychometric properties. Three language versions of the questionnaire were administered to a general population sample comprising 1000 participants (771 English-, 178 Afrikaans- and 101 Xhosa-speakers). Of these participants, 210 were randomly selected to establish test-retest reliability (70 in each language). Principal component analysis was performed to examine the applicability of the factor structure of the original questionnaire to the South African data. Supplementary psychometric analyses were performed, including internal consistency and test-retest reliability. Collectively, results provide initial evidence of the reliability and validity of the SPSI-R:SF for the assessment of problem solving deficits in South Africa. Further studies that explore how the Afrikaans language version of the SPSI-R:SF can be improved and that establish the predictive validity of scores on the SPSI-R:SF are needed. © 2015 International Union of Psychological Science.

Optimal Allocation of Sampling Effort in Depletion Surveys

EPA Science Inventory

We consider the problem of designing a depletion or removal survey as part of estimating animal abundance for populations with imperfect capture or detection rates. In a depletion survey, animals are captured from a given area, counted, and withheld from the population. This proc...

The Adopted Adolescent. Selected Papers Number 55.

ERIC Educational Resources Information Center

Banning, Anne

This review of studies on clinical and nonclinical populations explores outcomes of adoption and developmental issues for adolescents, and in particular, developmental problems for adopted adolescents. Studies on nonclinical populations demonstrate that adoption is a highly successful form of substitute care. Prospective longitudinal studies show…

A Multipopulation Coevolutionary Strategy for Multiobjective Immune Algorithm

PubMed Central

Shi, Jiao; Gong, Maoguo; Ma, Wenping; Jiao, Licheng

2014-01-01

How to maintain the population diversity is an important issue in designing a multiobjective evolutionary algorithm. This paper presents an enhanced nondominated neighbor-based immune algorithm in which a multipopulation coevolutionary strategy is introduced for improving the population diversity. In the proposed algorithm, subpopulations evolve independently; thus the unique characteristics of each subpopulation can be effectively maintained, and the diversity of the entire population is effectively increased. Besides, the dynamic information of multiple subpopulations is obtained with the help of the designed cooperation operator which reflects a mutually beneficial relationship among subpopulations. Subpopulations gain the opportunity to exchange information, thereby expanding the search range of the entire population. Subpopulations make use of the reference experience from each other, thereby improving the efficiency of evolutionary search. Compared with several state-of-the-art multiobjective evolutionary algorithms on well-known and frequently used multiobjective and many-objective problems, the proposed algorithm achieves comparable results in terms of convergence, diversity metrics, and running time on most test problems. PMID:24672330

Probability bounds analysis for nonlinear population ecology models.

PubMed

Enszer, Joshua A; Andrei Măceș, D; Stadtherr, Mark A

2015-09-01

Mathematical models in population ecology often involve parameters that are empirically determined and inherently uncertain, with probability distributions for the uncertainties not known precisely. Propagating such imprecise uncertainties rigorously through a model to determine their effect on model outputs can be a challenging problem. We illustrate here a method for the direct propagation of uncertainties represented by probability bounds though nonlinear, continuous-time, dynamic models in population ecology. This makes it possible to determine rigorous bounds on the probability that some specified outcome for a population is achieved, which can be a core problem in ecosystem modeling for risk assessment and management. Results can be obtained at a computational cost that is considerably less than that required by statistical sampling methods such as Monte Carlo analysis. The method is demonstrated using three example systems, with focus on a model of an experimental aquatic food web subject to the effects of contamination by ionic liquids, a new class of potentially important industrial chemicals. Copyright © 2015. Published by Elsevier Inc.

Echinococcosis: Control and Prevention.

PubMed

Craig, P S; Hegglin, D; Lightowlers, M W; Torgerson, P R; Wang, Q

2017-01-01

Human cystic echinococcosis (CE) has been eliminated or significantly reduced as a public health problem in several previously highly endemic regions. This has been achieved by the long-term application of prevention and control measures primarily targeted to deworming dogs, health education, meat inspection, and effective surveillance in livestock and human populations. Human CE, however, remains a serious neglected zoonotic disease in many resource-poor pastoral regions. The incidence of human alveolar echinococcosis (AE) has increased in continental Europe and is a major public health problem in parts of Eurasia. Better understanding of wildlife ecology for fox and small mammal hosts has enabled targeted anthelmintic baiting of fox populations and development of spatially explicit models to predict population dynamics for key intermediate host species and human AE risk in endemic landscapes. Challenges that remain for echinococcosis control include effective intervention in resource-poor communities, better availability of surveillance tools, optimal application of livestock vaccination, and management and ecology of dog and wildlife host populations. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Value of Information for Populations in Varying Environments

NASA Astrophysics Data System (ADS)

Rivoire, Olivier; Leibler, Stanislas

2011-04-01

The notion of information pervades informal descriptions of biological systems, but formal treatments face the problem of defining a quantitative measure of information rooted in a concept of fitness, which is itself an elusive notion. Here, we present a model of population dynamics where this problem is amenable to a mathematical analysis. In the limit where any information about future environmental variations is common to the members of the population, our model is equivalent to known models of financial investment. In this case, the population can be interpreted as a portfolio of financial assets and previous analyses have shown that a key quantity of Shannon's communication theory, the mutual information, sets a fundamental limit on the value of information. We show that this bound can be violated when accounting for features that are irrelevant in finance but inherent to biological systems, such as the stochasticity present at the individual level. This leads us to generalize the measures of uncertainty and information usually encountered in information theory.

Multi-Agent Inference in Social Networks: A Finite Population Learning Approach

PubMed Central

Tong, Xin; Zeng, Yao

2016-01-01

When people in a society want to make inference about some parameter, each person may want to use data collected by other people. Information (data) exchange in social networks is usually costly, so to make reliable statistical decisions, people need to trade off the benefits and costs of information acquisition. Conflicts of interests and coordination problems will arise in the process. Classical statistics does not consider people’s incentives and interactions in the data collection process. To address this imperfection, this work explores multi-agent Bayesian inference problems with a game theoretic social network model. Motivated by our interest in aggregate inference at the societal level, we propose a new concept, finite population learning, to address whether with high probability, a large fraction of people in a given finite population network can make “good” inference. Serving as a foundation, this concept enables us to study the long run trend of aggregate inference quality as population grows. PMID:27076691

Genetic algorithm enhanced by machine learning in dynamic aperture optimization

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

Li, Yongjun; Cheng, Weixing; Yu, Li Hua

With the aid of machine learning techniques, the genetic algorithm has been enhanced and applied to the multi-objective optimization problem presented by the dynamic aperture of the National Synchrotron Light Source II (NSLS-II) Storage Ring. During the evolution processes employed by the genetic algorithm, the population is classified into different clusters in the search space. The clusters with top average fitness are given “elite” status. Intervention on the population is implemented by repopulating some potentially competitive candidates based on the experience learned from the accumulated data. These candidates replace randomly selected candidates among the original data pool. The average fitnessmore » of the population is therefore improved while diversity is not lost. Maintaining diversity ensures that the optimization is global rather than local. The quality of the population increases and produces more competitive descendants accelerating the evolution process significantly. When identifying the distribution of optimal candidates, they appear to be located in isolated islands within the search space. Some of these optimal candidates have been experimentally confirmed at the NSLS-II storage ring. Furthermore, the machine learning techniques that exploit the genetic algorithm can also be used in other population-based optimization problems such as particle swarm algorithm.« less

Parliamentarians from CIS and the Far East reaffirm commitment to population program. Parliamentarians conference in Ulaanbaatar.

PubMed

1999-01-01

This article summarizes the proceedings of the Parliamentarian Conference held in Ulaanbaatar, Mongolia. Parliamentarian representatives from Japan, South Korea, China, Russia, and Commonwealth of Independent States countries agreed to work together in providing better lives to their people through rational population planning. Problems faced by the region, as mentioned in the conference, include persistently high maternal and infant mortality, internal migration from rural to urban areas, high unemployment rate, lower enrollment of boys and men as compared to girls and women in educational institutions, and environmental problems such as soil erosion resulting from over grazing. In addition, member representatives presented the status of the region's reproductive health/rights, gender and population policy, food security and environment, and adolescents and elderly. It was noted that there has been significant progress in reproductive health, gender equality, agricultural sector, and legislation for the youth and the elderly. However, these issues still need to be improved and developed. The UN Population Fund has reinforced its commitment towards population and development programs in the region, and the parliamentarians have reaffirmed its commitment to creating the legal framework favorable to the implementation of the Program of Action in the Ulaanbaatar Declaration.

Genetic algorithm enhanced by machine learning in dynamic aperture optimization

NASA Astrophysics Data System (ADS)

Li, Yongjun; Cheng, Weixing; Yu, Li Hua; Rainer, Robert

2018-05-01

With the aid of machine learning techniques, the genetic algorithm has been enhanced and applied to the multi-objective optimization problem presented by the dynamic aperture of the National Synchrotron Light Source II (NSLS-II) Storage Ring. During the evolution processes employed by the genetic algorithm, the population is classified into different clusters in the search space. The clusters with top average fitness are given "elite" status. Intervention on the population is implemented by repopulating some potentially competitive candidates based on the experience learned from the accumulated data. These candidates replace randomly selected candidates among the original data pool. The average fitness of the population is therefore improved while diversity is not lost. Maintaining diversity ensures that the optimization is global rather than local. The quality of the population increases and produces more competitive descendants accelerating the evolution process significantly. When identifying the distribution of optimal candidates, they appear to be located in isolated islands within the search space. Some of these optimal candidates have been experimentally confirmed at the NSLS-II storage ring. The machine learning techniques that exploit the genetic algorithm can also be used in other population-based optimization problems such as particle swarm algorithm.

Genetic algorithm enhanced by machine learning in dynamic aperture optimization

DOE PAGES

Li, Yongjun; Cheng, Weixing; Yu, Li Hua; ...

2018-05-29

With the aid of machine learning techniques, the genetic algorithm has been enhanced and applied to the multi-objective optimization problem presented by the dynamic aperture of the National Synchrotron Light Source II (NSLS-II) Storage Ring. During the evolution processes employed by the genetic algorithm, the population is classified into different clusters in the search space. The clusters with top average fitness are given “elite” status. Intervention on the population is implemented by repopulating some potentially competitive candidates based on the experience learned from the accumulated data. These candidates replace randomly selected candidates among the original data pool. The average fitnessmore » of the population is therefore improved while diversity is not lost. Maintaining diversity ensures that the optimization is global rather than local. The quality of the population increases and produces more competitive descendants accelerating the evolution process significantly. When identifying the distribution of optimal candidates, they appear to be located in isolated islands within the search space. Some of these optimal candidates have been experimentally confirmed at the NSLS-II storage ring. Furthermore, the machine learning techniques that exploit the genetic algorithm can also be used in other population-based optimization problems such as particle swarm algorithm.« less

Hematological reference values of healthy Malaysian population.

PubMed

Roshan, T M; Rosline, H; Ahmed, S A; Rapiaah, M; Wan Zaidah, A; Khattak, M N

2009-10-01

Health and disease can only be distinguished by accurate and reliable reference values of a particular laboratory test. It is now a proven fact that there is considerable variation in hematology reference intervals depending on the demographic and preanalytical variables. There are evidences that values provided by manufacturers do not have appropriate application for all populations. Moreover, reference ranges provided by different laboratory manuals and books also do not solve this problem. We are presenting here normal reference ranges of Malaysian population. These values were determined by using Sysmex XE-2100 and ACL 9000 hematology and coagulation analyzers. Results from this study showed that there were considerable differences in the reference values from manufacturers, western population or laboratory manuals compared with those from the local population.

[Demographic consequences of genetic load: a model of the origin of the incest taboo].

PubMed

Buzin, A Iu

1987-12-01

The prohibition of copulations among near relatives may raise the fitness of population. This effect being irregular and insignificant for a distinct generation, becomes apparent in evolutionary time intervals through the natural selection of populations with incest-taboo. The "characteristic selection time" theta depends on typical population size, genetic damage and the mean rate of population growth. The estimation obtained for theta permit us to assert that the model describes the phenomenon of "socio-cultural selection" in prehistory. The model shows the demographic specificity of small populations. The problem of the number of consanguineous marriages is considered in detail. New explanation for deviation of the observed frequency of consanguineous marriages from classical estimations is proposed.

[Problems of the birth rate of population and scientific-practical approaches to their solution].

PubMed

Deĭkun, M P

2003-01-01

Data are submitted to the effect that the population birth-rate is a national, political, and social problem rather than medical one only. An account is given of those factors affecting the level of birth-rate and health of newborn infants at the present stage of development of the society. Chief requirements the programme is to comply with are specified. Carrying out the projects suggested will, we believe, help in putting an end to further aggravation of the crisis.

Call for new approach of population / environment issue.

PubMed

1992-01-01

The US Committee on Women, Population, and the Environment strives for women's empowerment and reproductive freedom and opposes poverty, inequality, racism, and environmental degradation. Its members do not believe the leading causes of environmental degradation to be just population size and population growth. In fact, reducing population growth does not solve environmental degradation problems. The causes actually consist of an interrelationship of exploitative economic systems that focus on short-term gains and profits, military build up and actions that foster violence against women, uprooting of small farmers and indigenous people by international financial institutions with national governments agreeing to this action, technologies that abuse natural resources, rapid urbanization and poverty, and disproportionate consumption of industrialized nations and the wealthy worldwide. A major problem with blaming population growth for environmental degradation is it deepens the top down, demographically driven population policies and programs that do not value women, especially non-Caucasian women and their children. Specifically, they are not oriented toward women's reproductive health needs. Various programs have coerced women to undergo sterilization, have not given women medical screenings or follow-up care, have neglected informed consent, have not provided women with information on contraceptive risks and side efforts, and have not offered safe abortion and barrier and male family planning methods. Evidence worldwide indicates that improvements in living standards and in women's social, economic, and health status are the solution to reducing population growth. Thus, the Committee invites national governments, international agencies, and other social organizations to provide the resources needed for women's development and freedom (e.g. fair and equitable wages, women's participation in decision making, and appropriate health and reproductive health care).

Inequities in visual health and health services use in a rural region in Spain.

PubMed

Latorre-Arteaga, Sergio; Fernández-Sáez, José; Gil-González, Diana

2017-06-06

To analyse perceived visual health and health services use in a rural population in relation to socioeconomic characteristics and compared with the general population in Spain. Cross-sectional study in a rural population using a structured questionnaire including questions comparable to the Spanish National Health Survey (2012). A descriptive analysis was carried out through the calculation of frequencies and prevalence, the χ 2 test for independent variables, contrasts of proportions and logistic regression to obtain associations between the rural and general populations and socioeconomic variables. For the rural population studied, the prevalence of poor perceptions of visual health is 40.8% in men and 39.4% in women, and is strongly associated with age, employment situation, income and presence of chronic diseases (p ˂0.001). Compared with the general population, the rural population has a higher risk of presenting with serious difficulties related to farsightedness (OR: 2.56; 95% CI: 1.32-4.95) and make less use of optical correction (OR: 0.57; 95%CI: 0.44-0.74). The use of health services is not sufficient for adequate prevention, particularly in diabetics. For those affected by poor vision, the distance to travel to receive an eye exam, the belief that eyesight problems come with age and the cost of glasses are the principal reasons used to explain why eyesight problems are not resolved. The rural population presents worse visual health that is influenced by social and economic factors. Improving accessibility and reducing barriers is essential to tackle avoidable visual disability and reduce health inequities. Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

Environmental and genetic determinants of innovativeness in a natural population of birds

PubMed Central

Quinn, John L.; Cole, Ella F.; Reed, Thomas E.

2016-01-01

Much of the evidence for the idea that individuals differ in their propensity to innovate and solve new problems has come from studies on captive primates. Increasingly, behavioural ecologists are studying innovativeness in wild populations, and uncovering links with functional behaviour and fitness-related traits. The relative importance of genetic and environmental factors in driving this variation, however, remains unknown. Here, we present the results of the first large-scale study to examine a range of causal factors underlying innovative problem-solving performance (PSP) among 831 great tits (Parus major) temporarily taken into captivity. Analyses show that PSP in this population: (i) was linked to a variety of individual factors, including age, personality and natal origin (immigrant or local-born); (ii) was influenced by natal environment, because individuals had a lower PSP when born in poor-quality habitat, or where local population density was high, leading to cohort effects. Links with many of the individual and environmental factors were present only in some years. In addition, PSP (iii) had little or no measurable heritability, as estimated by a Bayesian animal model; and (iv) was not influenced by maternal effects. Despite previous reports of links between PSP and a range of functional traits in this population, the analyses here suggest that innovativeness had weak if any evolutionary potential. Instead most individual variation was caused by phenotypic plasticity driven by links with other behavioural traits and by environmentally mediated developmental stress. Heritability estimates are population, time and context specific, however, and more studies are needed to determine the generality of these effects. Our results shed light on the causes of innovativeness within populations, and add to the debate on the relative importance of genetic and environmental factors in driving phenotypic variation within populations. PMID:26926275

One hundred years of population ecology: Successes, failures and the road ahead.

PubMed

Krebs, Charles J

2015-05-01

Population ecology is the most mature of the three subdisciplines of ecology partly because it has a solid mathematical foundation and partly because it can address the primary questions of distribution and abundance with experimental protocols. Yet there is much left to do to integrate our population knowledge into community and ecosystem ecology to help address the global issues of food security and the conservation of biodiversity. Many different approaches are now being developed to bring about this integration and much more research will be necessary to decide which if any will be most useful in achieving our goals of explaining the changes we see in the distribution and abundance of animals and plants. Food web ecology would appear to be the best approach at present because it uses the detailed information of the population ecology of particular species in combination with data on consumer-resource interactions to apply to the applied problems of biodiversity conservation, food security, pest management and disease prevention. If we can use our understanding of population ecology to address the practical problems of our time in a creative way, we will benefit both the human population and the Earth's biodiversity. Much remains to be done. © 2015 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

Correlation between patients' reasons for encounters/health problems and population density in Japan: a systematic review of observational studies coded by the International Classification of Health Problems in Primary Care (ICHPPC) and the International Classification of Primary care (ICPC).

PubMed

Kaneko, Makoto; Ohta, Ryuichi; Nago, Naoki; Fukushi, Motoharu; Matsushima, Masato

2017-09-13

The Japanese health care system has yet to establish structured training for primary care physicians; therefore, physicians who received an internal medicine based training program continue to play a principal role in the primary care setting. To promote the development of a more efficient primary health care system, the assessment of its current status in regard to the spectrum of patients' reasons for encounters (RFEs) and health problems is an important step. Recognizing the proportions of patients' RFEs and health problems, which are not generally covered by an internist, can provide valuable information to promote the development of a primary care physician-centered system. We conducted a systematic review in which we searched six databases (PubMed, the Cochrane Library, Google Scholar, Ichushi-Web, JDreamIII and CiNii) for observational studies in Japan coded by International Classification of Health Problems in Primary Care (ICHPPC) and International Classification of Primary Care (ICPC) up to March 2015. We employed population density as index of accessibility. We calculated Spearman's rank correlation coefficient to examine the correlation between the proportion of "non-internal medicine-related" RFEs and health problems in each study area in consideration of the population density. We found 17 studies with diverse designs and settings. Among these studies, "non-internal medicine-related" RFEs, which was not thought to be covered by internists, ranged from about 4% to 40%. In addition, "non-internal medicine-related" health problems ranged from about 10% to 40%. However, no significant correlation was found between population density and the proportion of "non-internal medicine-related" RFEs and health problems. This is the first systematic review on RFEs and health problems coded by ICHPPC and ICPC undertaken to reveal the diversity of health problems in Japanese primary care. These results suggest that primary care physicians in some rural areas of Japan need to be able to deal with "non-internal-medicine-related" RFEs and health problems, and that curriculum including practical non-internal medicine-related training is likely to be important.

[Integration of demographic variables into development plans in the Sahel].

PubMed

Wane, H R

1992-07-01

A founding principle of the Program of Action of N'Djamena is the interdependence of population and development and the need for development strategies to take demographic factors into account. The concept of integration of population variables into development has evolved since its introduction in the 1974 World Population Plan of Action from a simple description of population size, growth rates, and distribution to a stress on harmonizing population policies and development policies with macroeconomic variables. The essence of the concept is the consideration given by development policies and programs to the interrelations between population, resources, the environment, and development factors. Population variables and goals should ideally be treated as endogenous variables in development planning, but in practice the extreme complexity of such a systematic approach limits its ability to be made operational. Usually the most crucial problems only are included. Integrated planning is composed of explicit or implicit population policies intended to influence demographic variables and of socioeconomic policies intended to adapt to demographic change. In the Sahel, only Senegal, Burkina Faso, and Mali have formal population policies, but around 1980 several countries of the region began to show interest in influencing demographic variables as they did economic variables. Fundamental principles for developing an integration strategy can be applied regardless or whether the plan is based on projections, analysis of interaction of a demographic variable with factors specific to a sector, or a monosectorial or multisectorial demoeconomic planning model. Demographic data is used more frequently in diagnosing problems than in developing projections or formulating objectives. The level of disaggregation of demographic projections and estimates tends to be low, despite the great potential utility of demographic projections in planning. Demographic projections can be useful in analyses of the extent of changes and the implications of alternative scenarios of development planning. The most frequently used demographic variables in development planning have been spatial distribution of the population and mortality. An examination of past development plans in Mali relating to population and nutrition and population and health reveals several inconsistencies between stated goals and strategies intended to achieve them. The incoherence can be explained in part by the absence of a coherent national population policy, the failure to translate the population policy into programs that take into account reciprocal effects of demographic trends and economic perspectives and their social effects, and the absence of disaggregated population projections. An example from Senegal demonstrates the constraints imposed by structural adjustment programs on the entire planning process.

Intermetropolitan Migration and the Rise of the Sunbelt.

ERIC Educational Resources Information Center

Watkins, Alfred J.

1978-01-01

Examines the historical patterns and components of the population flows that have contributed to recent metropolitan development in the sunbelt. Examines potential problems and fundamental contradictions inherent in both the continuation and cessation of the population influx. Suggests that these demographic and economic trends may seriously…

Compulsory Birth Control and Fertility Measures in India.

ERIC Educational Resources Information Center

Halli, S. S.

1983-01-01

Discussion of possible applications of the microsimulation approach to analysis of population policy proposes compulsory sterilization policy for all of India. Topics covered include India's population problem, methods for generating a distribution of couples to be sterilized, model validation, data utilized, data analysis, program limitations,…

An American Laboratory: Population Growth and Environmental Quality in California.

ERIC Educational Resources Information Center

McConnell, Robert

1993-01-01

Describes the cumulative impact of rapid population growth, industrial and military activity, agriculture, and motor vehicles on California's environmental and social fabric. Discusses these problems in California as a forecast for the nation and test to consensus-based U.S. representative government. (Author/ MCO)

The Federal Program in Population Research, Parts 1 and 2.

ERIC Educational Resources Information Center

Federal Council for Science and Technology, Washington, DC.

The first part of this report characterizes the many facets of the population problem (including biological, economic, and social aspects), suggests a list of areas in which the Federal Government should emphasize research (reproductive biology; fertility regulation techniques and materials; description, determinants, consequences of population…

Spending our soil resources

USDA-ARS?s Scientific Manuscript database

A third of the world's population suffers from food insecurity. With an expected 2 billion population increase in the next few decades, that number is expected to rise significantly, leading to more people that are insecure and starving unless our soils can produce more food. Added to the problem ar...

No Nation Alone

ERIC Educational Resources Information Center

Chase, Stuart

1976-01-01

Summarized are 13 major problems facing every country in the world today. Problems include: disarmament, population explosion, pollution, energy, conservation of natural resources, transportation, communications, and health. (SL)

Aging in Hong Kong: the institutional population.

PubMed

Woo, Jean; Chau, Patsy P H

2009-09-01

The Hong Kong population is aging rapidly, such that there are concerns about residential care adequacy in terms of number of places as well as quality of care. A total of 1820 residents living in a representative sample of residential care facilities were surveyed. The survey showed a substantial proportion with cognitive dysfunction, mood problems, communication and vision problems, chronic disabling diseases, impairment in activities of daily living, and undernutrition. Programs of activities and rehabilitation were generally unavailable. Those in for-profit facilities had a worse profile. An approximate estimation of numbers of staff required based on case mix revealed considerable understaffing among the for-profit facilities. Issues of quality of care would be all the more important with anticipated future increase in the institutional population of older people.

Maslow's Hierarchy of Needs and the individual with chronic vestibular dysfunction.

PubMed

Haybach, P J

1994-01-01

Individuals with chronic vestibular dysfunction may have unmet physiological or safety needs on a chronic basis. Their inability to fulfill the basic needs and progress to higher needs can lead to a patient population with many psychosocial problems. Very often such problems are ignored or unrecognized or are misdiagnosed, and treated inappropriately. This disruption in the individual's life can lead to an inability to progress as a human being. Nursing assessment and appropriate interventions should be developed to treat psychosocial problems in this patient population. The nursing profession should serve patients with vestibular dysfunction through direct care, teaching, counseling, support group facilitation, and research into appropriate interventions.

HIV counselling in prisons.

PubMed

Curran, L; McHugh, M; Nooney, K

1989-01-01

HIV presents particular problem in penal establishments: the nature of the population; conditions in prison; media attention and misinformation; the possibility of transmission within and beyond the prison population; the extra issues that apply to female prisoners. These are discussed in the context of prison policy regarding HIV and the broad strategic approach which is being adopted to manage the problem of HIV within penal institutions. Counselling has a key role in the overall strategy. Pre- and post-test counselling with prisoners is described and the particular problems presented by inmates are discussed and illustrated by reference to case histories. Developments in counselling provision for inmates are outlined.

On extreme points of the diffusion polytope

DOE PAGES

Hay, M. J.; Schiff, J.; Fisch, N. J.

2017-01-04

Here, we consider a class of diffusion problems defined on simple graphs in which the populations at any two vertices may be averaged if they are connected by an edge. The diffusion polytope is the convex hull of the set of population vectors attainable using finite sequences of these operations. A number of physical problems have linear programming solutions taking the diffusion polytope as the feasible region, e.g. the free energy that can be removed from plasma using waves, so there is a need to describe and enumerate its extreme points. We also review known results for the case ofmore » the complete graph Kn, and study a variety of problems for the path graph Pn and the cyclic graph Cn. Finall, we describe the different kinds of extreme points that arise, and identify the diffusion polytope in a number of simple cases. In the case of increasing initial populations on Pn the diffusion polytope is topologically an n-dimensional hypercube.« less

Effect of ancient population structure on the degree of polymorphism shared between modern human populations and ancient hominins.

PubMed

Eriksson, Anders; Manica, Andrea

2012-08-28

Recent comparisons between anatomically modern humans and ancient genomes of other hominins have raised the tantalizing, and hotly debated, possibility of hybridization. Although several tests of hybridization have been devised, they all rely on the degree to which different modern populations share genetic polymorphisms with the ancient genomes of other hominins. However, spatial population structure is expected to generate genetic patterns similar to those that might be attributed to hybridization. To investigate this problem, we take Neanderthals as a case study, and build a spatially explicit model of the shared history of anatomically modern humans and this hominin. We show that the excess polymorphism shared between Eurasians and Neanderthals is compatible with scenarios in which no hybridization occurred, and is strongly linked to the strength of population structure in ancient populations. Thus, we recommend caution in inferring admixture from geographic patterns of shared polymorphisms, and argue that future attempts to investigate ancient hybridization between humans and other hominins should explicitly account for population structure.

Endless urban growth? On the mismatch of population, household and urban land area growth and its effects on the urban debate.

PubMed

Haase, Dagmar; Kabisch, Nadja; Haase, Annegret

2013-01-01

In European cities, the rate of population growth has declined significantly, while the number of households has increased. This increase in the number of households is associated with an increase in space for housing. To date, the effects of both a declining population and decreasing household numbers remain unclear. In this paper, we analyse the relationship between population and household number development in 188 European cities from 1990-2000 and 2000-2006 to the growth of urban land area and per capita living space. Our results support a trend toward decreasing population with simultaneously increasing household number. However, we also found cites facing both a declining population and a decreasing household number. Nevertheless, the urban land area of these "double-declining" cities has continued to spread because the increasing per capita living space counteracts a reduction in land consumption. We conclude that neither a decline in population nor in household number "automatically" solve the global problem of land consumption.

Natural Selection in Large Populations

NASA Astrophysics Data System (ADS)

Desai, Michael

2011-03-01

I will discuss theoretical and experimental approaches to the evolutionary dynamics and population genetics of natural selection in large populations. In these populations, many mutations are often present simultaneously, and because recombination is limited, selection cannot act on them all independently. Rather, it can only affect whole combinations of mutations linked together on the same chromosome. Methods common in theoretical population genetics have been of limited utility in analyzing this coupling between the fates of different mutations. In the past few years it has become increasingly clear that this is a crucial gap in our understanding, as sequence data has begun to show that selection appears to act pervasively on many linked sites in a wide range of populations, including viruses, microbes, Drosophila, and humans. I will describe approaches that combine analytical tools drawn from statistical physics and dynamical systems with traditional methods in theoretical population genetics to address this problem, and describe how experiments in budding yeast can help us directly observe these evolutionary dynamics.

Weak ergodicity of population evolution processes.

PubMed

Inaba, H

1989-10-01

The weak ergodic theorems of mathematical demography state that the age distribution of a closed population is asymptotically independent of the initial distribution. In this paper, we provide a new proof of the weak ergodic theorem of the multistate population model with continuous time. The main tool to attain this purpose is a theory of multiplicative processes, which was mainly developed by Garrett Birkhoff, who showed that ergodic properties generally hold for an appropriate class of multiplicative processes. First, we construct a general theory of multiplicative processes on a Banach lattice. Next, we formulate a dynamical model of a multistate population and show that its evolution operator forms a multiplicative process on the state space of the population. Subsequently, we investigate a sufficient condition that guarantees the weak ergodicity of the multiplicative process. Finally, we prove the weak and strong ergodic theorems for the multistate population and resolve the consistency problem.

Evolutionary dynamics on any population structure

NASA Astrophysics Data System (ADS)

Allen, Benjamin; Lippner, Gabor; Chen, Yu-Ting; Fotouhi, Babak; Momeni, Naghmeh; Yau, Shing-Tung; Nowak, Martin A.

2017-03-01

Evolution occurs in populations of reproducing individuals. The structure of a population can affect which traits evolve. Understanding evolutionary game dynamics in structured populations remains difficult. Mathematical results are known for special structures in which all individuals have the same number of neighbours. The general case, in which the number of neighbours can vary, has remained open. For arbitrary selection intensity, the problem is in a computational complexity class that suggests there is no efficient algorithm. Whether a simple solution for weak selection exists has remained unanswered. Here we provide a solution for weak selection that applies to any graph or network. Our method relies on calculating the coalescence times of random walks. We evaluate large numbers of diverse population structures for their propensity to favour cooperation. We study how small changes in population structure—graph surgery—affect evolutionary outcomes. We find that cooperation flourishes most in societies that are based on strong pairwise ties.

A quantitative model of honey bee colony population dynamics.

PubMed

Khoury, David S; Myerscough, Mary R; Barron, Andrew B

2011-04-18

Since 2006 the rate of honey bee colony failure has increased significantly. As an aid to testing hypotheses for the causes of colony failure we have developed a compartment model of honey bee colony population dynamics to explore the impact of different death rates of forager bees on colony growth and development. The model predicts a critical threshold forager death rate beneath which colonies regulate a stable population size. If death rates are sustained higher than this threshold rapid population decline is predicted and colony failure is inevitable. The model also predicts that high forager death rates draw hive bees into the foraging population at much younger ages than normal, which acts to accelerate colony failure. The model suggests that colony failure can be understood in terms of observed principles of honey bee population dynamics, and provides a theoretical framework for experimental investigation of the problem.

Isolation with Migration Models for More Than Two Populations

PubMed Central

Hey, Jody

2010-01-01

A method for studying the divergence of multiple closely related populations is described and assessed. The approach of Hey and Nielsen (2007, Integration within the Felsenstein equation for improved Markov chain Monte Carlo methods in population genetics. Proc Natl Acad Sci USA. 104:2785–2790) for fitting an isolation-with-migration model was extended to the case of multiple populations with a known phylogeny. Analysis of simulated data sets reveals the kinds of history that are accessible with a multipopulation analysis. Necessarily, processes associated with older time periods in a phylogeny are more difficult to estimate; and histories with high levels of gene flow are particularly difficult with more than two populations. However, for histories with modest levels of gene flow, or for very large data sets, it is possible to study large complex divergence problems that involve multiple closely related populations or species. PMID:19955477

Isolation with migration models for more than two populations.

PubMed

Hey, Jody

2010-04-01

A method for studying the divergence of multiple closely related populations is described and assessed. The approach of Hey and Nielsen (2007, Integration within the Felsenstein equation for improved Markov chain Monte Carlo methods in population genetics. Proc Natl Acad Sci USA. 104:2785-2790) for fitting an isolation-with-migration model was extended to the case of multiple populations with a known phylogeny. Analysis of simulated data sets reveals the kinds of history that are accessible with a multipopulation analysis. Necessarily, processes associated with older time periods in a phylogeny are more difficult to estimate; and histories with high levels of gene flow are particularly difficult with more than two populations. However, for histories with modest levels of gene flow, or for very large data sets, it is possible to study large complex divergence problems that involve multiple closely related populations or species.

L'éducation des adultes et le vieillissement des populations: Tendances et enjeux

NASA Astrophysics Data System (ADS)

Bélanger, Paul

1992-07-01

The aging of the population is accompanied by profound changes in life cycles, and it calls into question the models of institutional relationship between education, work and leisure time. After reviewing some concepts of aging, the author places the "training-work-retirement" triad in the context of the transformation of paid work and the new scenarios of ways in which people finally leave the labour market. Two questions are then asked: In what way may aging populations change the demand for adult continuing education? And, what is the significance of the present educational response to the problems posed by the aging of the population?

Redistribution population data across a regular spatial grid according to buildings characteristics

NASA Astrophysics Data System (ADS)

Calka, Beata; Bielecka, Elzbieta; Zdunkiewicz, Katarzyna

2016-12-01

Population data are generally provided by state census organisations at the predefined census enumeration units. However, these datasets very are often required at userdefined spatial units that differ from the census output levels. A number of population estimation techniques have been developed to address these problems. This article is one of those attempts aimed at improving county level population estimates by using spatial disaggregation models with support of buildings characteristic, derived from national topographic database, and average area of a flat. The experimental gridded population surface was created for Opatów county, sparsely populated rural region located in Central Poland. The method relies on geolocation of population counts in buildings, taking into account the building volume and structural building type and then aggregation the people total in 1 km quadrilateral grid. The overall quality of population distribution surface expressed by the mean of RMSE equals 9 persons, and the MAE equals 0.01. We also discovered that nearly 20% of total county area is unpopulated and 80% of people lived on 33% of the county territory.

India's demographic snapshot, 1991.

PubMed

Bose, A

1991-12-01

Having presented the provisional results of the 1991 Census of India in tabular form, the author discusses the policy implication of the data. During the 1981-91 decade, India witnesses a 160.99 net increase in population, which brought the country's total population to an estimated 844.32 million. The annual growth rated during the decade was 2.1%. The author explains that these alarming population figures reflect the failure of the government's population program. The author warns that unless the Planning Commission develops new strategies, the upcoming 5-year plans. The author explains that the failure of family planning is due primarily to the low literacy rate -- especially the female literacy rate is 29% (and 25% among rural women). The author also discusses the problems of urbanization and the work force. During the past decade, cities grew at a somewhat slower rate than in previous decades, meaning that the absorptive capacity of the cities has gone down. Nonetheless, the urban population grew by 58 million during 10-year period. The urban infrastructure is virtually collapsing, with 30-50% of the urban population living in slums. The data also reveals the structural stagnation of the economy. The agricultural sector, which accounts for about 2/3 of the work force, registered only slight decreases during the decade, signifying a marginal shift from agriculture to nonagricultural activity. Furthermore, population growth has aggravated the unemployment problem. Finally, the author addresses the issue of the sex ratio (females/1000 males), which declined from 934 in 1981 to 929 in 1991, which indicates a continued prejudice against women.

Violence reported by the immigrant population is high as compared with the native population in southeast Spain.

PubMed

Colorado-Yohar, S; Tormo, M J; Salmerón, D; Dios, S; Ballesta, M; Navarro, C

2012-11-01

Immigrants constitute a population vulnerable to the problem of violence. This study sought to ascertain the prevalence of violence reported by the immigrant population in the Murcian Region of Spain and characterize the related factors, taking the country population as reference. A cross-sectional study was carried out based on a representative population sample of Latin American (n = 672; 48% women), Moroccan (n = 361; 25% women), and Spanish origin (n = 1,303; 66% women), aged 16 to 64 years. Using a specific questionnaire, the prevalence of violence in the preceding year was assessed. The results were compared with the Spaniards using the 2006 National Health Survey (NHS). Multivariate logistic regression models were used to study the factors associated with violence having been reported in each group, both separately and in immigrants versus Spaniards. Finally, the cause and place of last aggression were studied. The prevalence of violence was 6.5% in Latin Americans, 12.0% in Moroccans, and 2.7% in Spaniards. Discrimination was the principal violence-related factor in all three groups. Among Latin Americans, low educational level was also associated with violence. Among Moroccans, those who had perceived discrimination showed the greatest differences in prevalence of violence compared with natives. Intimate partner violence (IPV) registered a prevalence of below 2%. As a conclusion, in this study, violence was little reported and higher among immigrants. The principal violence-related factor was discrimination. More studies of this type are called for to characterize the problem in other population-representative samples.

Mating System and Effective Population Size of the Overexploited Neotropical Tree (Myroxylon peruiferum L.f.) and Their Impact on Seedling Production.

PubMed

Silvestre, Ellida de Aguiar; Schwarcz, Kaiser Dias; Grando, Carolina; de Campos, Jaqueline Bueno; Sujii, Patricia Sanae; Tambarussi, Evandro Vagner; Macrini, Camila Menezes Trindade; Pinheiro, José Baldin; Brancalion, Pedro Henrique Santin; Zucchi, Maria Imaculada

2018-03-16

The reproductive system of a tree species has substantial impact on genetic diversity and structure within and among natural populations. Such information, should be considered when planning tree planting for forest restoration. Here, we describe the mating system and genetic diversity of an overexploited Neotropical tree, Myroxylon peruiferum L.f. (Fabaceae) sampled from a forest remnant (10 seed trees and 200 seeds) and assess whether the effective population size of nursery-grown seedlings (148 seedlings) is sufficient to prevent inbreeding depression in reintroduced populations. Genetic analyses were performed based on 8 microsatellite loci. M. peruiferum presented a mixed mating system with evidence of biparental inbreeding (t^m-t^s = 0.118). We found low levels of genetic diversity for M. peruiferum species (allelic richness: 1.40 to 4.82; expected heterozygosity: 0.29 to 0.52). Based on Ne(v) within progeny, we suggest a sample size of 47 seed trees to achieve an effective population size of 100. The effective population sizes for the nursery-grown seedlings were much smaller Ne = 27.54-34.86) than that recommended for short term Ne ≥ 100) population conservation. Therefore, to obtain a reasonable genetic representation of native tree species and prevent problems associated with inbreeding depression, seedling production for restoration purposes may require a much larger sampling effort than is currently used, a problem that is further complicated by species with a mixed mating system. This study emphasizes the need to integrate species reproductive biology into seedling production programs and connect conservation genetics with ecological restoration.

Simulating the evolution of glyphosate resistance in grains farming in northern Australia.

PubMed

Thornby, David F; Walker, Steve R

2009-09-01

The evolution of resistance to herbicides is a substantial problem in contemporary agriculture. Solutions to this problem generally consist of the use of practices to control the resistant population once it evolves, and/or to institute preventative measures before populations become resistant. Herbicide resistance evolves in populations over years or decades, so predicting the effectiveness of preventative strategies in particular relies on computational modelling approaches. While models of herbicide resistance already exist, none deals with the complex regional variability in the northern Australian sub-tropical grains farming region. For this reason, a new computer model was developed. The model consists of an age- and stage-structured population model of weeds, with an existing crop model used to simulate plant growth and competition, and extensions to the crop model added to simulate seed bank ecology and population genetics factors. Using awnless barnyard grass (Echinochloa colona) as a test case, the model was used to investigate the likely rate of evolution under conditions expected to produce high selection pressure. Simulating continuous summer fallows with glyphosate used as the only means of weed control resulted in predicted resistant weed populations after approx. 15 years. Validation of the model against the paddock history for the first real-world glyphosate-resistant awnless barnyard grass population shows that the model predicted resistance evolution to within a few years of the real situation. This validation work shows that empirical validation of herbicide resistance models is problematic. However, the model simulates the complexities of sub-tropical grains farming in Australia well, and can be used to investigate, generate and improve glyphosate resistance prevention strategies.

The problem of estimating recent genetic connectivity in a changing world.

PubMed

Samarasin, Pasan; Shuter, Brian J; Wright, Stephen I; Rodd, F Helen

2017-02-01

Accurate understanding of population connectivity is important to conservation because dispersal can play an important role in population dynamics, microevolution, and assessments of extirpation risk and population rescue. Genetic methods are increasingly used to infer population connectivity because advances in technology have made them more advantageous (e.g., cost effective) relative to ecological methods. Given the reductions in wildlife population connectivity since the Industrial Revolution and more recent drastic reductions from habitat loss, it is important to know the accuracy of and biases in genetic connectivity estimators when connectivity has declined recently. Using simulated data, we investigated the accuracy and bias of 2 common estimators of migration (movement of individuals among populations) rate. We focused on the timing of the connectivity change and the magnitude of that change on the estimates of migration by using a coalescent-based method (Migrate-n) and a disequilibrium-based method (BayesAss). Contrary to expectations, when historically high connectivity had declined recently: (i) both methods over-estimated recent migration rates; (ii) the coalescent-based method (Migrate-n) provided better estimates of recent migration rate than the disequilibrium-based method (BayesAss); (iii) the coalescent-based method did not accurately reflect long-term genetic connectivity. Overall, our results highlight the problems with comparing coalescent and disequilibrium estimates to make inferences about the effects of recent landscape change on genetic connectivity among populations. We found that contrasting these 2 estimates to make inferences about genetic-connectivity changes over time could lead to inaccurate conclusions. © 2016 Society for Conservation Biology.

Childhood lead poisoning in a Somali refugee resettlement community in New Hampshire.

PubMed

Caron, Rosemary M; Tshabangu-Soko, Thandi; Finefrock, Krysten

2013-08-01

Despite the gradual decrease in childhood lead poisoning in the United States, the risk for lead poisoning among African refugee children who resettle in the United States remains elevated. Communication methods implemented by resettlement agencies in the public health system for preventing childhood lead poisoning in this at-risk population warrant further investigation. We utilized structured interviews with key stakeholders (resettlement agencies, social service agencies developed by African refugees and resettled Somali refugees) involved in the refugee resettlement process to (1) describe the agency's role in the refugee resettlement process; (2) examine communication methods utilized and barriers experienced by the public health system in reference to childhood lead poisoning; (3) describe the refugee population's perception of childhood lead poisoning; (4) examine general challenges experienced by the public health system and the refugee population during the resettlement process; and (5) describe stakeholders' recommendations to improve health communication efforts. Based on our findings, we propose that communities are important determinants in health-related problems for refugee populations. Each community has its own environment and public health system that interacts with each other to influence health risks and risk perceptions of its populations. We advocate that understanding a community's ecology and implementing a culture-centered approach is essential for the public health system to help educate and prevent communication inequalities and health disparities among an at-risk African refugee population. This action can reduce a population's resistance to communication and help build a community's capacity to address a persistent public health problem, such as childhood lead poisoning.

Population pressure and human carrying capacity in selected locations of Machakos and Kitui districts.

PubMed

Bernard, F E; Thom, D J

1981-04-01

The nature and magnitude of population pressure in Machakos and Kitui Districts of Kenya were investigated. Specific study objectives were: 1) to examine the roots and evolution of the problem; 2) to compute carrying capacity for a sample of locations and ecozones in the 2 districts; and 3) to consider agricultural and demographic implications of the findings. Carrying capacity is defined as the number of people and the level of their activities which a region is able to sustain in perpetuity at an acceptable quality of life and without land deterioration. A methodology for calculating human carrying capacity utilizing crude soil, ecological, crop yield, and land use data for 41 locations in Machakos and Kitui Districts is demonstrated. Analysis and a comparison of population carrying capacities within the study area reveals that Machakos has reached a critical level of population pressure. To the north in Mbere and eastward in Kitui there are areas that are not currently experiencing population pressure, but it is likely that as the pressure in western Machakos becomes more acute, movement into these adjacent lands of relatively sparse settlement will increase. Signs of environmental stress resulting from overpopulation are evident throughout Machakos. The methodology used for estimating population pressure provided reasonably accurate carrying capacity estimates, but the methodology could be refined. Vigorous efforts to rejuvenate the land through soil and water conservation have been undertaken, but these have been insufficient and must be increased. Such efforts will fail unless the basic problem of population pressure in the marginal lands is resolved.

Long-Term Health-Related Quality of Life in German Patients with Juvenile Idiopathic Arthritis in Comparison to German General Population.

PubMed

Barth, Swaantje; Haas, Johannes-Peter; Schlichtiger, Jenny; Molz, Johannes; Bisdorff, Betty; Michels, Hartmut; Hügle, Boris; Radon, Katja

2016-01-01

Aims of the study were to investigate health-related quality of life (HRQOL) in adult patients with former diagnosis of Juvenile Idiopathic Arthritis (JIA), to compare their HRQOL with the general population and to identify factors related to a poor outcome. In 2012, a cross-sectional survey was performed by mailing a questionnaire to a large cohort of former and current patients of the German Centre for Rheumatology in Children and Adolescents. Only adult patients (≥18 years) with a diagnosis compatible with JIA were included (n = 2592; response 66%). The questionnaire included information about HRQOL (EQ5D), disease-related questions and socio-demographics. Prevalence and 95% confidence intervals (CI) of problems with mobility, self-care, usual activities, pain and anxiety/depression were standardized to the German general population. Factors associated with low HRQOL in JIA patients were identified using logistic regression models. Sixty-two percent of the study population was female; age range was 18-73 years. In all dimensions, JIA patients reported statistically significantly more problems than the general population with largest differences in the pain dimension (JIA patients 56%; 95%CI 55-58%; general population 28%; 26-29%) and the anxiety/depression dimension (28%; 27-29% vs. 4%; 4-5%). Lower HRQOL in JIA patients was associated with female sex, older age, lower level of education, still being under rheumatic treatment and disability. HRQOL in adult JIA patients is considerably lower than in the general population. As this cohort includes historic patients the new therapeutic schemes available today are expected to improve HRQOL in future.

Assessment of vehicle safety problems for special driving populations

DOT National Transportation Integrated Search

1979-02-16

The report describes vehicle safety problems reported in interviews with 460 physically limited drivers and 41 physically limited non-drivers. The problems reported involved operation of primary and secondary controls, operating other vehicle mechani...

Initiating Population Education in Baltimore

ERIC Educational Resources Information Center

Cochran, Caroline S.; McCrea, Lester C.

1974-01-01

After identifying the need for population education in Baltimore City Schools, the school system had the problem of initiating such a course. Working with the Planned Parenthood Association of Maryland, the school system sponsored an in-service program for teachers that resulted in the production of materials for all grades. (MA)

The Educational Effects of Rapid Rural Population Growth.

ERIC Educational Resources Information Center

Ross, Peggy J.; Green, Bernal L.

Rapid population growth in rural areas has confronted rural communities and particularly rural educational systems with a number of problems. Sudden, large increases in students crowd school facilities and strain budgets. The different values, attitudes, and orientations toward education of the newcomers act as a catalyst for changes and can cause…

The World Social Situation: Development Challenges at the Outset of a New Century

ERIC Educational Resources Information Center

Estes, Richard J.

2010-01-01

World social development has arrived at a critical turning point. Economically advanced nations have made significant progress toward meeting the basic needs of their populations; however, the majority of developing countries have not. Problems of rapid population growth, failing economies, famine, environmental devastation, majority-minority…

Gambling: A Poison Chalice for Indigenous Peoples'

ERIC Educational Resources Information Center

Dyall, Lorna

2010-01-01

Indigenous populations are now being encouraged to be involved in the business of gambling as an operator or if not given that status, are actively encouraged to participate in gambling activities. Research both published and unpublished show that different indigenous populations often have a higher prevalence of problem and pathological gambling…

UNICOR Users Manual

Treesearch

E. L. Landguth; B. K. Hand; J. M. Glassy; S. A. Cushman; R. T. Carlson

2011-01-01

Habitat loss and its effects on populations of vulnerable species is among the most urgent problems in conservation ecology. It is critical that managers and scientists have effective tools to evaluate the effects of landuse and climate change on the extent and connectivity of populations. To address this need, we introduce UNIversal CORridor network simulator (UNICOR...

ALTERATIONS IN DEVELOPMENT OF REPRODUCTIVE AND ENDOCRINE SYSTEMS OF WILDLIFE POPULATIONS EXPOSED TO ENDOCRINE-DISRUPTING CONTAMINANTS.

EPA Science Inventory

Wildlife and human populations are affected by contaminants in natural settings. This problem has been a growing concern over the last decade with the realization that various environmental chemicals can alter the development and functioning of endocrine organs, cells and target ...

Tunnel Vision in Population Research: A Case in Point.

ERIC Educational Resources Information Center

Serron, Luis A.

This paper takes a critical look at a demographic study of Mexico, namely, Tad Fisher's "Mexico: The Problem of People". Fisher's study relies heavily on population growth as a poverty generating factor. The paper states that Fisher's study exhibited perceptual narrowness by not considering the Marxist interpretation that capitalist…

Mexican-Americans: Problems and Prospects.

ERIC Educational Resources Information Center

Moore, Joan W.

Comprising the second largest minority group in the United States, 87% of the Mexican American population live in five states in the Southwest. Characterized by a high birth rate, continuous immigration, and low income, the Mexicqn American population is an increasing source of concern in a welfare-oriented society. Educational attainment levels…

Teaching Population Ecology Modeling by Means of the Hewlett-Packard 9100A.

ERIC Educational Resources Information Center

Tuinstra, Kenneth E.

The incorporation of mathematical modeling experiences into an undergraduate biology course is described. Detailed expositions of three models used to teach concepts of population ecology are presented, including introductions to major concepts, user instructions, trial data and problem sets. The models described are: 1) an exponential/logistic…

Temperament, Parenting, and Depressive Symptoms in a Population Sample of Preadolescents

ERIC Educational Resources Information Center

Oldehinkel, Albertine J.; Veenstra, Rene; Ormel, Johan; De Winter, Andrea F.; Verhulst, Frank C.

2006-01-01

Background: Depressive symptoms can be triggered by negative social experiences and individuals' processing of these experiences. This study focuses on the interaction between temperament, perceived parenting, and gender in relation to depressive problems in a Dutch population sample of preadolescents. Methods: The sample consisted of 2230…

Spending our water and soils for food security

USDA-ARS?s Scientific Manuscript database

A third of the world’s population suffers from food insecurity. With an expected 2 billion population increase in the next few decades that number is expected to rise significantly, leading to more people that are insecure and starving unless our soils can produce more food. Added to the problem are...

The Changing Balance of Births and Deaths: A Comment.

ERIC Educational Resources Information Center

Schultz, T. Paul

Commenting on Kingsley Davis' paper, "Population Policy: Will Current Programs Succeed?", the author discusses the problem of rapid population growth in the low-income countries. Research strategy should focus on the family or small community to trace environmental constraints and opportunities influencing desired and achieved fertility, and…

Is Pseudoscymnus tsugae the solution to the hemlock woolly adelgid problem?: An early perspective

Treesearch

Mark S. McClure; Carole A. S-J. Cheah; Timothy C. Tigner

2000-01-01

Hemlock woolly adelgid, Adelges tsugae Annand (Homoptera: Adelgidae) is native to Japan where it is an innocuous inhabitant of Tsuga diversifolia Masters and T. sieboldii Carriere. Native populations of this insect are regulated by host resistance and natural enemies. However, introduced populations in eastern...

Demographic, Employment and Development Trends: The Need for Integrated Planning.

ERIC Educational Resources Information Center

Farooq, Ghazi M.; MacKellar, F. Landis

1990-01-01

The authors contend that problems associated with rapid population growth in developing countries must be tackled through comprehensive planning. They discuss impacts of demography on labor supply and demand and migration. Then they propose a practical framework for population and human resource development planning and policy formation. (SK)

Thinking about Feelings: Emotion Focus in the Parenting of Children with Early Developmental Risk

ERIC Educational Resources Information Center

Baker, J. K.; Crnic, K. A.

2009-01-01

Background: Children with developmental delays exhibit more difficulty with certain emotional processes than their typically developing peers, which seems to partially account for the increased risk for the development of social problems in this population. Despite considerable study with typically developing populations, research on parental…

Anxiety in Asperger's Syndrome: Assessment in Real Time

ERIC Educational Resources Information Center

Hare, Dougal J.; Wood, Christopher; Wastell, Sarah; Skirrow, Paul

2015-01-01

Anxiety is a major problem for many people with Asperger's syndrome who may have qualitatively different fears from a non-Asperger's syndrome population. Research has relied on measures developed for non-Asperger's syndrome populations that require reporting past experiences of anxiety, which may confound assessment in people with Asperger's…

Population and Development Issues.

ERIC Educational Resources Information Center

Cohen, Sharon; Garran, Christopher

1998-01-01

Describes a unit on demographics for a high school world-history course that addresses questions of uneven population growth and the "problem of global overpopulation." Provides a detailed outline of the two-day unit including unit and daily goals and objectives, daily activities and questions, and ideas for further student research. (DSK)

Underserved Gifted Populations: Responding to Their Needs and Abilities. Perspectives on Creativity Research.

ERIC Educational Resources Information Center

Smutny, Joan Franklin, Ed.

Twenty-five papers address issues of the underserved gifted, including environmental influences, multicultural and global factors, special learning problems, and the highly gifted and creatively gifted. The papers are: "Twenty-five Teaching Strategies that Promote Learning Success for Underserved Gifted Populations" (Jerry Flack); "The Invisible…

Point Counts of Birds: What Are We Estimating?

Treesearch

Douglas H. Johnson

1995-01-01

Point counts of birds are made for many reasons, including estimating local densities, determining population trends, assessing habitat preferences, and exploiting the activities of recreational birdwatchers. Problems arise unless there is a clear understanding of what point counts mean in terms of actual populations of birds. Criteria for conducting point counts...

China marks World Population Day. Address by Zhang Weiqing: (Excerpts).

PubMed

Zhang, W

1998-08-01

This is a summary of remarks by Minister Zhang Weiqing of China's State Family Planning Commission (SFPC) given on World Population Day in China. The world's population size has increased by 1 billion since 1987, and will reach 6 billion by 1999. As the most populous developing country in the world, China has a greater population pressure and bears a large responsibility regarding stabilization of the world's population and realization of sustainable development. China has a less developed economy and a high percentage of rural and illiterate persons, many of whom are below the poverty line. The interests of both present and future generations must be taken into account with regard to development. In addition, the modernization drive must include strategies for sustainable development and basic national policies of FP and environmental protection in order to achieve a balance among population growth, the economy, resources, and the environment. After 30 years of effort, China has succeeded in solving its population problem by integrating governmental guidance with voluntary public participation in FP. In 1997, the birthrate decreased to 16.57/1000, and the total fertility rate was below replacement level. Changes in attitude toward marriage and childbearing have occurred, as has awareness of voluntary participation in FP. However, some problems have emerged in the implementation of population and FP programs. China will carry out its programs strictly and effectively while developing the national economy. Goals include: 1) stressing the IEC program regarding contraception and regular FP management and services; 2) integrating the FP program with economic development; 3) helping the public to become well off; 4) protecting maternal and child health; 5) improving the status of women; 6) delivering reproductive services; and 7) improving social security measures. Efforts will be made to enable the public to have a more active part in implementing the FP program.

The Near-Earth Orbital Debris Problem and the Challenges for Environment Remediation

NASA Technical Reports Server (NTRS)

Liou, Jer-Chyi

2012-01-01

The near-Earth space environment has been gradually polluted with orbital debris (OD) since the beginning of space activities 55 years ago. Although this problem has been known to the research community for decades, the public was, in general, unaware of the issue until the anti-satellite test conducted by China in 2007 and the collision between Cosmos 2251 and the operational Iridium 33 in 2009. The latter also underlined the potential of an ongoing collision cascade effect (the "Kessler Syndrome") in the low Earth orbit (LEO, the region below 2000 km altitude). Recent modeling results have indicated that mitigation measures commonly adopted by the international space community will be insufficient to stabilize the LEO debris population. To better limit the OD population increase, more aggressive actions must be considered. There are three options for OD environment remediation-removal of large/massive intact objects to address the root cause of the OD population growth problem, removal of 5-mm-to-1 cm debris to mitigate the main mission-ending threats for the majority of operational spacecraft, and prevention of major debris-generating collisions as a temporary means to slow down the OD population increase. The technology, engineering, and cost challenges to carry out any of these three options are monumental. It will require innovative ideas, game-changing technologies, and major collaborations at the international level to address the OD problem and preserve the near-Earth environment for future generations.

Genetic Divergence Disclosing a Rapid Prehistorical Dispersion of Native Americans in Central and South America

PubMed Central

He, Yungang; Wang, Wei R.; Li, Ran; Wang, Sijia; Jin, Li

2012-01-01

An accurate estimate of the divergence time between Native Americans is important for understanding the initial entry and early dispersion of human beings in the New World. Current methods for estimating the genetic divergence time of populations could seriously depart from a linear relationship with the true divergence for multiple populations of a different population size and significant population expansion. Here, to address this problem, we propose a novel measure to estimate the genetic divergence time of populations. Computer simulation revealed that the new measure maintained an excellent linear correlation with the population divergence time in complicated multi-population scenarios with population expansion. Utilizing the new measure and microsatellite data of 21 Native American populations, we investigated the genetic divergences of the Native American populations. The results indicated that genetic divergences between North American populations are greater than that between Central and South American populations. None of the divergences, however, were large enough to constitute convincing evidence supporting the two-wave or multi-wave migration model for the initial entry of human beings into America. The genetic affinity of the Native American populations was further explored using Neighbor-Net and the genetic divergences suggested that these populations could be categorized into four genetic groups living in four different ecologic zones. The divergence of the population groups suggests that the early dispersion of human beings in America was a multi-step procedure. Further, the divergences suggest the rapid dispersion of Native Americans in Central and South Americas after a long standstill period in North America. PMID:22970308

The concerned significant others of people with gambling problems in a national representative sample in Sweden - a 1 year follow-up study.

PubMed

Svensson, Jessika; Romild, Ulla; Shepherdson, Emma

2013-11-21

Research into the impact of problem gambling on close social networks is scarce with the majority of studies only including help-seeking populations. To date only one study has examined concerned significant others (CSOs) from an epidemiological perspective and it did not consider gender. The aim of this study is to examine the health, social support, and financial situations of CSOs in a Swedish representative sample and to examine gender differences. A population study was conducted in Sweden in 2008/09 (n = 15,000, response rate 63%). Respondents were defined as CSOs if they reported that someone close to them currently or previously had problems with gambling. The group of CSOs was further examined in a 1-year follow up (weighted response rate 74% from the 8,165 respondents in the original sample). Comparisons were also made between those defined as CSOs only at baseline (47.7%, n = 554) and those defined as CSOs at both time points. In total, 18.2% of the population were considered CSOs, with no difference between women and men. Male and female CSOs experienced, to a large extent, similar problems including poor mental health, risky alcohol consumption, economic hardship, and arguments with those closest to them. Female CSOs reported less social support than other women and male CSOs had more legal problems and were more afraid of losing their jobs than other men. One year on, several problems remained even if some improvements were found. Both male and female CSOs reported more negative life events in the 1 year follow-up. Although some relationships are unknown, including between the CSOs and the individuals with gambling problems and the causal relationships between being a CSO and the range of associated problems, the results of this study indicate that gambling problems not only affect the gambling individual and their immediate close family but also the wider social network. A large proportion of the population can be defined as a CSO, half of whom are men. While male and female CSOs share many common problems, there are gender differences which need to be considered in prevention and treatment.

Back pain in a large Canadian police force.

PubMed

Brown, J J; Wells, G A; Trottier, A J; Bonneau, J; Ferris, B

1998-04-01

A survey of a random sample of 1002 members of the Royal Canadian Mounted Police to determine their experience with low back pain. To determine the prevalence of low back pain among Royal Canadian Mounted Police members and to assess the validity of the perception that the patrol car seat and the duty belt are causing a higher rate of low back pain among members of the Royal Canadian Mounted Police than in the general population. Low back pain is a common problem throughout the industrialized world, with reported 1-year prevalence rates between 25% and 62%. Prevalence of low back pain among people who drive motor vehicles for a significant part of the day appears higher than in the general population. Among police officers, 1-year prevalence rates of between 44% and 62% have been reported. A computerized database of 14,897 serving regular members was used to identify a sample of officers on active duty. A low back pain questionnaire was mailed to each selected member, eliciting information regarding their experience with low back pain, their exposure to known and putative risk factors, and their opinions about the contribution of these potential risk factors. The respondents to the questionnaire remained anonymous. The response rate was 80%. The prevalence of "chronic or recurring low back pain since joining the force" was 54.9%, which is comparable with the lifetime prevalence reported for the general population. Of those who reported having back problems, only 8.5% had such problems before joining the force. Seventy-six percent who had low back pain reported having a problem within the last year, giving an overall 1-year prevalence of 41.8%, which is comparable with that for the general population. The a priori assumption that driving or wearing a duty belt contributed to the problem was shared by most police officers surveyed. However, only about half of the members who replied drove for more than half the working day or wore the duty belt. These members had the same prevalence of low back pain as those who did not drive or wear the duty belt. The prevalence of low back pain in this police force is comparable with that in the general population, and driving a patrol car or wearing the duty belt does not appear to influence the prevalence rate in this population.

A Population Health Surveillance Theory

PubMed Central

Bigras-Poulin, Michel; Michel, Pascal; Ravel, André

2012-01-01

OBJECTIVES Despite its extensive use, the term "Surveillance" often takes on various meanings in the scientific literature pertinent to public health and animal health. A critical appraisal of this literature also reveals ambiguities relating to the scope and necessary structural components underpinning the surveillance process. The authors hypothesized that these inconsistencies translate to real or perceived deficiencies in the conceptual framework of population health surveillance. This paper presents a population health surveillance theory framed upon an explicit conceptual system relative to health surveillance performed in human and animal populations. METHODS The population health surveillance theory reflects the authors' system of thinking and was based on a creative process. RESULTS Population health surveillance includes two broad components: one relating to the human organization (which includes expertise and the administrative program), and one relating to the system per se (which includes elements of design and method) and which can be viewed as a process. The population health surveillance process is made of five sequential interrelated steps: 1) a trigger or need, 2) problem formulation, 3) surveillance planning, 4) surveillance implementation, and 5) information communication and audit. CONCLUSIONS The population health surveillance theory provides a systematic way of understanding, organizing and evaluating the population health surveillance process. PMID:23251837

Transplant commercialism and organ trafficking: the Declaration of Istanbul with special relevance to disadvantaged populations living with kidney disease.

PubMed

Levin, Adeera; Muller, Elmi; Alrukhaimi, Mona; Naicker, Saralah; Tibbel, Annika

2015-01-01

This paper provides a historical perspective on organ trafficking and transplant commercialism, an overview of the Declaration of Istanbul [1, 2], and an update on current state. We highlight the importance of this problem pertaining to disadvantaged populations living with or at risk for kidney disease. It was presented during the Kidney Disease in Disadvantaged Populations Satellite Symposium of the World Congress of Nephrology in Hong Kong 2013 (www.theisn.org).

A Model with Darwinian Dynamics on a Rugged Landscape

NASA Astrophysics Data System (ADS)

Brotto, Tommaso; Bunin, Guy; Kurchan, Jorge

2017-02-01

We discuss the population dynamics with selection and random diffusion, keeping the total population constant, in a fitness landscape associated with Constraint Satisfaction, a paradigm for difficult optimization problems. We obtain a phase diagram in terms of the size of the population and the diffusion rate, with a glass phase inside which the dynamics keeps searching for better configurations, and outside which deleterious `mutations' spoil the performance. The phase diagram is analogous to that of dense active matter in terms of temperature and drive.

[A comparative presentation of the population policies of Burkina Faso, Mali and Senegal].

PubMed

Dabo, K

1992-07-01

Population policies are currently at the center of debates about demography and development, and are a preoccupation of most governments, international organizations, and research institutions working in the areas of population, development, and human resources. Between 1988-93, 4 Sahel countries adopted populations policies. this article compares the policies of Senegal, Mali, and Burkina Faso. The 3 policy documents have similar structures, with preambles recalling the international agreements concerning population and development entered into by their governments. A chapter on population and development describes the demo-economic problem in each country at regional, sectorial, and global levels. After the analysis of demo-economic problems, each of the 3 has a chapter presenting the population policy. Each presentation covers the foundations and basic principles of the policy, its objectives, the strategies to be pursued, and the organizational structure. Development of each policy was technically supervised by the Planning Ministry in collaboration with the national population councils. In general terms, the 3 countries recognize in their basic principles that the population is the primary source of wealth of a nation. Each country states its desire to translate the recommendations of different African and world population conferences into concrete acts. The principles avow respect for fundamental human rights including the right to informed decision making by couples on number and spacing of children. The principles also recognize the need for an integrated approach to population and development. The ultimate objective of the population policies is improvement in the standard and quality of life. The number of general objectives outlined in the policies varied from 7 in Senegal to 13 in Burkina Faso. Senegal was the only country of the 3 to specify reduction of the fertility rate and the growth rate as an objective. Senegal and Burkina Faso included quantified mortality objectives. The strategies of the 3 countries include improving the health of the population and of mothers and children in particular, promoting family planning, providing IEC on health and population topics, integrating women into development by improving their socioeconomic status, developing human resources through employment and education, developing territorial management systems for control of spatial distribution and internal migration, satisfying the basic needs of the population, protecting the environment, and providing training and research in relevant disciplines such as demography, statistics, and economics. Specific contraceptive prevalence goals stated in the policies were 24.04% of fertile aged women in Senegal in 2011, 60% in Burkina Faso in 2005, and 60% in Mali in 2020. Each country specified different entities for decision making, consultation, and execution of different phases of the population policy.

The dynamics of adapting, unregulated populations and a modified fundamental theorem.

PubMed

O'Dwyer, James P

2013-01-06

A population in a novel environment will accumulate adaptive mutations over time, and the dynamics of this process depend on the underlying fitness landscape: the fitness of and mutational distance between possible genotypes in the population. Despite its fundamental importance for understanding the evolution of a population, inferring this landscape from empirical data has been problematic. We develop a theoretical framework to describe the adaptation of a stochastic, asexual, unregulated, polymorphic population undergoing beneficial, neutral and deleterious mutations on a correlated fitness landscape. We generate quantitative predictions for the change in the mean fitness and within-population variance in fitness over time, and find a simple, analytical relationship between the distribution of fitness effects arising from a single mutation, and the change in mean population fitness over time: a variant of Fisher's 'fundamental theorem' which explicitly depends on the form of the landscape. Our framework can therefore be thought of in three ways: (i) as a set of theoretical predictions for adaptation in an exponentially growing phase, with applications in pathogen populations, tumours or other unregulated populations; (ii) as an analytically tractable problem to potentially guide theoretical analysis of regulated populations; and (iii) as a basis for developing empirical methods to infer general features of a fitness landscape.

Prevalence of sexual problems and its association with social, psychological and physical factors among men in a Malaysian population: a cross-sectional study.

PubMed

Quek, Kia Fatt; Sallam, Atiya Abdul; Ng, Chai Heng; Chua, Chong Beng

2008-01-01

Sexual problems are common in the general population. Studies have shown that most of these sexual problems are related to their social lives, medical illnesses, and psychological status. Among the sexual problems in men, premature ejaculation (PE) is one of the most frequent, yet it is the least well-understood of the sexual dysfunctions of men. To determine the prevalence of sexual problem particularly PE and erectile dysfunction (ED) among people living in urban areas and to investigate the characteristics associated with these sexual problems in a Malaysian population. The PE which is defined as an intravaginal ejaculation latency time less than 2 minutes was assessed in the ED and non-ED group. The Hospital Anxiety and Depression scale is used as a measure of the psychological status [30]. The ED status was assessed using the International Index of Erectile Function questionnaire. The prevalence of self-reported sexual problems for ED and PE were 41.6% and 22.3%, respectively. In those subjects with ED, 33.5% reported to have PE. Of the total of 430 subjects, anxiety was present in 8.1%, while depression was 5.3%. The prevalence of PE accounted for 25% anxiety and 14.6% for depression respectively in the population. EDs were associated with diabetes and hypertension (OR [95% CI]: 5.33 [2.33, 10.16], 3.40 [1.76, 6.57], P < 0.05), respectively, while factors associated with PE were anxiety and depression (OR [95% CI]: 1.29 [0.68, 2.45], 1.39 [0.69, 2.78]), respectively. Prevalence of ED is associated with medical symptoms such as diabetes and hypertension and a rise in the prevalence of age while psychological distress such as anxiety and depression also contribute to a higher PE rate.

Recognizing the professionals who help to solve "the population problem".

PubMed

Miro, C A

1984-12-01

It is the population professionals who belong to the "developing" world who have helped to create and expand the basic information which makes it possible to describe the demographic situation of countries and social groups more adequately. These professionals have developed, promoted, and applied analytical techniques which have enriched understanding of the components of demographic change. It is these professionals who have managed to make major contributions towards explaining the relationship between demographic and socioeconomic factors. The professionals are insisting on developing applied, theoretical, and methodological population research, the results of which will serve essentially to propose alternatives for action. This group of professionals participates daily in the training of technical staff and professionals and academics, specialists who will continue to promote the development of demography as a discipline. Finally, these professionals, through various publications, keep population topics at the center of the attention of those who are concerned with studying them. Groups of countries in Africa, Asia, and Latin America suffer, although to a different extent and in different ways, from the problems created by the rapid growth of certain cities, particularly capital cities. In addition to the problems which may arise from the operation of the specific population dynamics in different countries and between different social groups within those countries, there are those arising from the unequal distribution of agricultural land, foodstuffs, and wealth in general, those arising from the unjust organization of the international economy and from the obsolete international financial structure, and those deriving from the irrational use of resources for military spending and the manufacture and stockpiling of vast nuclear arsenals.

Prevalence and correlates of mental health problems among awaiting trial inmates in a Prison facility in Ibadan, Nigeria

PubMed Central

Abdulmalik, JO; Adedokun, BO; Baiyewu, OO

2014-01-01

Introduction Prevalence of mental health problems are frequently higher within the prison populations than the general population. Previous studies of prison mental health had focused on convict populations whereas, the awaiting trial segment of the prison population in Nigeria has gradually become the majority of the total lock-up. This study aimed to evaluate the prevalence and correlates of mental health problems among the awaiting trial inmates in a prison facility in Ibadan. Methods A cross sectional study design was employed to interview 725 awaiting trial inmates of Agodi Prison, Ibadan, Nigeria. A two phase procedure was utilized with initial screening using a socio-demographic questionnaire and the General Health Questionnaire (GHQ −12); followed by a second phase with all high scorers on the GHQ −12 and 10% of the low scorers using the MINI International Neuropsychiatric Inventory (MINI). Results A total of 394 respondents participated in the second phase of the study with a mean age of 31.1 years (SD = 8.7), with ages ranging from 18 – 70 years. The mean duration of incarceration at Agodi was 1.1 years (SD = 1.47), with a range of 1 week to 10 years. The prevalence of mental illness was 56.6% with the commonest conditions being depression (20.8%), alcohol dependence (20.6%), substance dependence (20.1%), suicidality (19.8%) and antisocial personality disorder (18%). Conclusion There is a high prevalence of neuropsychiatric disorders among awaiting trial inmates but this does not appear to be significantly different from that of convict populations. PMID:26689928

Has the world really survived the population bomb? (Commentary on "how the world survived the population bomb: lessons from 50 years of extraordinary demographic history").

PubMed

Becker, Stan

2013-12-01

In his PAA presidential address and corresponding article in Demography, David Lam (Demography 48:1231-1262, 2011) documented the extraordinary progress of humankind-vis-à-vis poverty alleviation, increased schooling, and reductions in mortality and fertility-since 1960 and noted that he expects further improvements by 2050. However, although Lam briefly covered the problems of global warming and pollution, he did not address several other major environmental problems that are closely related to the rapid human population growth in recent decades and to the progress he described. This commentary highlights some of these problems to provide a more balanced perspective on the situation of the world. Specifically, humans currently are using resources at an unsustainable level. Groundwater depletion and overuse of river water are major problems on multiple continents. Fossil fuel resources and several minerals are being depleted. Other major problems include deforestation, with the annual forest clearing globally estimated to be an area the size of New York State; and species extinction, with rates estimated to be 100 to 1,000 times higher than background rates. Principles of ecological economics are presented that allow an integration of ecology and economic development and better potential for preservation of the world for future generations.

What we know and don't know about mental health problems among immigrants in Norway.

PubMed

Abebe, Dawit Shawel; Lien, Lars; Hjelde, Karin Harsløf

2014-02-01

Mental health problems have been regarded as one of the main public health challenges of immigrants in several countries. Understanding and generating research-based knowledge on immigrant health problems is highly relevant for planning preventive interventions, as well as guiding social and policy actions. This review aims to map the available knowledge on immigrants' mental health status and its associated risk factors in Norway. The reviewed literature about mental health problems among immigrant populations in Norway was found through databases, such as PUBMED, EMBASE, PsychINFO and MEDLINE. About 41 peer-reviewed original articles published since 1990s were included. In the majority of the studies, the immigrant populations, specifically adult immigrants from low and middle income countries, have been found with a higher degree of mental health problems compared to Norwegians and the general population. Increased risk for mental illness is primarily linked to a higher risk for acculturative stress, poor social support, deprived socioeconomic conditions, multiple negative life events, experiences of discrimination and traumatic pre-migration experiences. However, research in this field has been confronted by a number of gaps and methodological challenges. The available knowledge indicates a need for preventive interventions. Correspondingly, it strongly recommends a comprehensive research program that addresses gaps and methodological challenges.

How often do they meet? Genetic similarity between European populations of a potential disease vector Culex pipiens.

PubMed

Lõhmus, Mare; Lindström, Anders; Björklund, Mats

2012-01-01

Species in the Culex pipiens complex are common almost all over the world and represent important vectors for many serious zoonotic diseases. Even if, at the moment, many of the pathogens potentially transmitted by Cx. pipiens are not a problem in northern Europe, they may, with increasing temperatures and changing ecosystems caused by climate change, move northward in the future. Therefore, the question whether or not the Cx. pipiens populations in northern Europe will be competent vectors for them is of high importance. One way to estimate the similarity and the rate of contact between European Cx. pipiens populations is to look at the gene exchange between these populations. To test the genetic diversity and degree of differentiation between European Cx. pipiens populations, we used eight microsatellite markers in 10 mosquito populations originating from northern, central, and southern Europe. We found that three of the analyzed populations were very different from the rest of the populations and they also greatly differed from each other. When these three populations were removed, the variance among the rest of the populations was low, suggesting an extensive historic gene flow between many European Cx. pipiens populations. This suggests that infectious diseases spread by this species may not be associated with a certain vector genotype but rather with suitable environmental conditions. Consequently, we would expect these pathogens to disperse northward with favorable climatic parameters.

Meeting review. Uncovering the genetic basis of adaptive change: on the intersection of landscape genomics and theoretical population genetics.

PubMed

Joost, Stéphane; Vuilleumier, Séverine; Jensen, Jeffrey D; Schoville, Sean; Leempoel, Kevin; Stucki, Sylvie; Widmer, Ivo; Melodelima, Christelle; Rolland, Jonathan; Manel, Stéphanie

2013-07-01

A workshop recently held at the École Polytechnique Fédérale de Lausanne (EPFL, Switzerland) was dedicated to understanding the genetic basis of adaptive change, taking stock of the different approaches developed in theoretical population genetics and landscape genomics and bringing together knowledge accumulated in both research fields. Indeed, an important challenge in theoretical population genetics is to incorporate effects of demographic history and population structure. But important design problems (e.g. focus on populations as units, focus on hard selective sweeps, no hypothesis-based framework in the design of the statistical tests) reduce their capability of detecting adaptive genetic variation. In parallel, landscape genomics offers a solution to several of these problems and provides a number of advantages (e.g. fast computation, landscape heterogeneity integration). But the approach makes several implicit assumptions that should be carefully considered (e.g. selection has had enough time to create a functional relationship between the allele distribution and the environmental variable, or this functional relationship is assumed to be constant). To address the respective strengths and weaknesses mentioned above, the workshop brought together a panel of experts from both disciplines to present their work and discuss the relevance of combining these approaches, possibly resulting in a joint software solution in the future.

Stability and Optimal Harvesting of Modified Leslie-Gower Predator-Prey Model

NASA Astrophysics Data System (ADS)

Toaha, S.; Azis, M. I.

2018-03-01

This paper studies a modified of dynamics of Leslie-Gower predator-prey population model. The model is stated as a system of first order differential equations. The model consists of one predator and one prey. The Holling type II as a predation function is considered in this model. The predator and prey populations are assumed to be beneficial and then the two populations are harvested with constant efforts. Existence and stability of the interior equilibrium point are analysed. Linearization method is used to get the linearized model and the eigenvalue is used to justify the stability of the interior equilibrium point. From the analyses, we show that under a certain condition the interior equilibrium point exists and is locally asymptotically stable. For the model with constant efforts of harvesting, cost function, revenue function, and profit function are considered. The stable interior equilibrium point is then related to the maximum profit problem as well as net present value of revenues problem. We show that there exists a certain value of the efforts that maximizes the profit function and net present value of revenues while the interior equilibrium point remains stable. This means that the populations can live in coexistence for a long time and also maximize the benefit even though the populations are harvested with constant efforts.

Emotional development in children with tics: a longitudinal population-based study.

PubMed

Hoekstra, P J; Lundervold, A J; Lie, S A; Gillberg, C; Plessen, Kerstin J

2013-03-01

Children with tics often experience accompanying problems that may have more impact on their well being and quality of life than the tics themselves. The present study investigates characteristics and the course of associated problems. In a population-based follow-up study, we investigated the developmental trajectory of children with and without tics when they were 7-9 years old. Parents and teachers completed the strengths and difficulties questionnaire (SDQ) when the children were 7-9 years (wave 1) and 4 years later (wave 2). Using strict criteria, we identified 38 children with tics in the cohort of 4,025 children (0.94% of the total cohort) with a preponderance of boys (78.9%). 22 children (57.9%) in the group with tics had only motor tics, and 16 (42.1%) had both motor and vocal tics. Children with tics had significantly higher parent- and teacher-rated SDQ total difficulty scores and subscale scores in both waves. Children with tics experienced an increase in emotional problems and in peer problems between the first and the second wave. This study in a general population indicates that the presence of tics is associated with a range of internalizing and externalizing difficulties, as well as problems in peer relationships. Moreover, our study indicates that emotional and peer problems tend to increase over time in the group of children with tics.

Statement by Minister Peng Peiyun at the International Conference on Population and Development.

PubMed

Peng, P

1994-10-01

The speech of Madam Peng Peiyun, state counselor and minister of the State Family Planning Commission in China, before the International Conference on Population and Development in Cairo in 1994, emphasized 6 basic points about fertility decline. 1) Population as an issue is about development. The only solution is to work toward sustained development of productivity while promoting social and economic development in environmentally protected ways. 2) Governments should provide "acceptable, obtainable, and affordable" quality family planning services. Governments should help couples and individuals freely and responsibly decide on childbearing without coercion. 3) There is no one recommended model for reducing rapid population growth and enhancing development. Countries have different cultures, levels of economic development, population conditions, and historical traditions. 4) Women's status should be improved through expansion of opportunities for education, involvement in politics and economic development, legal protection of women's rights and interests, and "realization of gender equality." Women need more information, education, and counseling on reproductive health and family planning. Males need to take more responsibility for family planning. 5) International cooperation and government responsibility are required for stabilization of population growth and attainment of sustainable development. Developing countries need improved economic conditions, increased investment in population and development programs, and transfers of technology from developed countries. The principles of mutual respect and mutual benefit according to the spirit of the UN Charter should prevail. UN organizational support should function according to the principles of universality and neutrality. 6) China's goal is to achieve sustained economic growth and development, to meet the material and cultural needs of the Chinese people, and to improve the quality of Chinese life. Without controlled population growth in China, 1.2 billion people will not have sufficient food and clothing and mass global migration will occur. About 80 million Chinese people currently are lacking in these basic necessities. China's Agenda 21 and the Outline for Social Development of China 1996-2010 will address these problems and provide strategies for integrated development and fertility decline. China aims to work harder at solving the population growth problems of its own and to try to contribute to global population stabilization, peace, and cooperation.

The globalization of epidemiology: introductory remarks.

PubMed

Pearce, Neil

2004-10-01

We are all living in the era of globalization, and like it or not, it is going to change the way we practice epidemiology, the kinds of questions we ask, and the methods we use to answer them. Increasingly, pubic health problems are being shifted from rich countries to poor countries and from rich to poor populations within Western countries. There is increasing interest and concern about the situation in non-Western populations on the part of Western epidemiologists, with regards to collaborative research, skills transfer, and 'volunteerism' to enable the 'benefits' of Western approaches to epidemiology to be shared by the non-Western world. However, most existing collaborations benefit Western epidemiologists rather than the countries in which the research is conducted. Even when research in non-Western populations is conducted as a genuine collaboration, it can too often 'export failure' from the West. On the other hand, non-Western epidemiologists are increasingly developing new and innovative approaches to health research that are more appropriate to the global public health issues they are addressing. These include recognition of the importance of context and the importance of diversity and local knowledge, and a problem-based approach to addressing the major public health problems using appropriate technology. These debates formed the background for a plenary session on 'International Epidemiology and International Health' at the recent International Epidemiological Association (IEA) meeting in Montreal, and the papers from this session are presented here. The development of a truly global epidemiology can not only better address the public health problems in non-Western populations, but can shed light on the current limitations of epidemiology in addressing the major public health problems in the West.

Solving the problem of negative populations in approximate accelerated stochastic simulations using the representative reaction approach.

PubMed

Kadam, Shantanu; Vanka, Kumar

2013-02-15

Methods based on the stochastic formulation of chemical kinetics have the potential to accurately reproduce the dynamical behavior of various biochemical systems of interest. However, the computational expense makes them impractical for the study of real systems. Attempts to render these methods practical have led to the development of accelerated methods, where the reaction numbers are modeled by Poisson random numbers. However, for certain systems, such methods give rise to physically unrealistic negative numbers for species populations. The methods which make use of binomial variables, in place of Poisson random numbers, have since become popular, and have been partially successful in addressing this problem. In this manuscript, the development of two new computational methods, based on the representative reaction approach (RRA), has been discussed. The new methods endeavor to solve the problem of negative numbers, by making use of tools like the stochastic simulation algorithm and the binomial method, in conjunction with the RRA. It is found that these newly developed methods perform better than other binomial methods used for stochastic simulations, in resolving the problem of negative populations. Copyright © 2012 Wiley Periodicals, Inc.

Predator-prey dynamics stabilised by nonlinearity explain oscillations in dust-forming plasmas

NASA Astrophysics Data System (ADS)

Ross, A. E.; McKenzie, D. R.

2016-04-01

Dust-forming plasmas are ionised gases that generate particles from a precursor. In nature, dust-forming plasmas are found in flames, the interstellar medium and comet tails. In the laboratory, they are valuable in generating nanoparticles for medicine and electronics. Dust-forming plasmas exhibit a bizarre, even puzzling behaviour in which they oscillate with timescales of seconds to minutes. Here we show how the problem of understanding these oscillations may be cast as a predator-prey problem, with electrons as prey and particles as predators. The addition of a nonlinear loss term to the classic Lotka-Volterra equations used for describing the predator-prey problem in ecology not only stabilises the oscillations in the solutions for the populations of electrons and particles in the plasma but also explains the behaviour in more detail. The model explains the relative phase difference of the two populations, the way in which the frequency of the oscillations varies with the concentration of the precursor gas, and the oscillations of the light emission, determined by the populations of both species. Our results demonstrate the value of adopting an approach to a complex physical science problem that has been found successful in ecology, where complexity is always present.

Accounting for missing data in the estimation of contemporary genetic effective population size (N(e) ).

PubMed

Peel, D; Waples, R S; Macbeth, G M; Do, C; Ovenden, J R

2013-03-01

Theoretical models are often applied to population genetic data sets without fully considering the effect of missing data. Researchers can deal with missing data by removing individuals that have failed to yield genotypes and/or by removing loci that have failed to yield allelic determinations, but despite their best efforts, most data sets still contain some missing data. As a consequence, realized sample size differs among loci, and this poses a problem for unbiased methods that must explicitly account for random sampling error. One commonly used solution for the calculation of contemporary effective population size (N(e) ) is to calculate the effective sample size as an unweighted mean or harmonic mean across loci. This is not ideal because it fails to account for the fact that loci with different numbers of alleles have different information content. Here we consider this problem for genetic estimators of contemporary effective population size (N(e) ). To evaluate bias and precision of several statistical approaches for dealing with missing data, we simulated populations with known N(e) and various degrees of missing data. Across all scenarios, one method of correcting for missing data (fixed-inverse variance-weighted harmonic mean) consistently performed the best for both single-sample and two-sample (temporal) methods of estimating N(e) and outperformed some methods currently in widespread use. The approach adopted here may be a starting point to adjust other population genetics methods that include per-locus sample size components. © 2012 Blackwell Publishing Ltd.

Causes of mortality in anuran amphibians from an ex situ survival assurance colony in Panama.

PubMed

Pessier, Allan P; Baitchman, Eric J; Crump, Paul; Wilson, Brad; Griffith, Edgardo; Ross, Heidi

2014-01-01

The success of ex situ survival assurance populations as tools for amphibian conservation depends on the health and reproductive success of founder populations. Necropsy examination and histopathology of animals that die in assurance populations are useful for the identification of population-limiting disease problems and can help to direct applied research efforts in areas such as amphibian husbandry and nutrition. This study reviewed postmortem findings in 167 frogs from 13 species that died in a large Panamanian rescue and survival assurance population between 2006 and 2011. Common problems identified in long-term captive animals, especially in Atelopus species, were epithelial squamous metaplasia suggestive of vitamin A deficiency and a polycystic nephropathy resembling lesions seen in laboratory animals with electrolyte imbalances. Metabolic bone disease was a significant contributor to morbidity in captive-bred juvenile frogs of Gastrotheca cornuta, Hemiphractus fasciatus, and Hylomantis lemur. Findings common to multiple species included poor overall nutritional condition that was sometimes attributable to maladaptation to captive husbandry and epidermal hyperplasia and hyperkeratosis possibly reflecting environmental skin irritation. Infectious diseases and endoparasitism were most common in recently captured animals and included chytridiomycosis and Rhabdias sp. lungworms. Applied research efforts to improve sustainability of survival assurance populations should focus on elucidating optimal husbandry practices for diverse species, improving methods for nutritional supplementation of cultured insects and examination of the role of water composition in disease development. © 2014 Wiley Periodicals Inc.

Are psychology university student gamblers representative of non-university students and general gamblers? A comparative analysis.

PubMed

Gainsbury, Sally M; Russell, Alex; Blaszczynski, Alex

2014-03-01

Students recruited from psychology undergraduate university populations are commonly used in psychology research, including gambling studies. However, the extent to which the use of this subpopulation produces findings that can be extrapolated to other groups is questionable. The present study was designed to compare results from university-recruited psychology student gamblers to those obtained from a sample of gamblers recruited from the general population that also included students. An online survey measuring gambling behavior and Internet gambling, attitudes and knowledge about gambling and problem gambling severity was posted on websites accessed by gamblers. Participants were recruited from two sources, a psychology undergraduate university population (n = 461) and online websites (n = 4,801). Results showed university-recruited students differed significantly from both adults and students recruited from the general population in respect to demographic variables and gambling behavior. Psychology undergraduate students were younger, more likely to be female, and had lower incomes. When relevant demographic variables were controlled, psychology undergraduate students were found to gamble less frequently, at different times, and to be at lower-risk for gambling-related problems, but had more irrational beliefs and more negative attitudes towards gambling than gamblers recruited from the general population. Results suggest that caution should be used in extrapolating findings from research using university-recruited psychology student gamblers to wide community populations due to differences related to gambling thoughts, attitudes and behaviors.

Cancer in populations living in regions with radioecological problems in Bulgaria.

PubMed

Chobanova, N; Genchev, G; Yagova, A; Georgieva, L

2003-01-01

To analyse the incidence and mortality of some malignant diseases among the population living in regions of past uranium extraction in Bulgaria. A retrospective study on cancer incidence and mortality in the population living around two regions with radioecological problems was conducted. According to the expected individual annual effective doses for the population, regions with expected highest radiation risk (average effective dose > 10 mSv per year) were the villages Yana, Eleshnitza and Seslavtzi (group A), and with expected relatively high radiation risk (average effective dose > 5 mSv per year) were the town of Buhovo, and the villages Dolni Bogrov and Gorni Bogrov (group B). The ecologically clean village German was chosen as a control settlement. The incidence and mortality of gastrointestinal tract cancers, bronchus and lung cancer, breast cancer, thyroid cancer, and myeloid leukaemia for the period 1995- 2001 were studied. The incidence of the gastrointestinal tract cancers in the population of German was significantly lower than those for Bulgaria and for group B. The mortality from this disease of groups A, B and Bulgaria were significantly higher than in the control settlement. Standardized mortality of lung cancer in the population of the villages with highest and relatively high radiation risk was significantly higher than in German and Bulgaria. The incidence and mortality changes of diseases studied are a consequence of the impact of many factors. Moreover, they do not characterize the impact of the radiation factor.

Population policy: do we need it? Prospects and problems.

PubMed

Moyo, N P

1986-01-01

A 1983 report by the Whitsun Foundation called upon the Government of Zimbabwe to recognize the urgent nature of that country's population problem and to devise and implement a comprehensive population policy aimed at reducing morbidity and mortality among women and children, reducing the population growth rate, and reducing the fertility level. This article challenges the Whitsun Foundation's view that population pressure is the primary cause of poverty in Zimbabwe and that family planning is a feasible remedy. It is argued instead that poverty in Zimbabwe can be traced to capitalist development policies that have removed from rural people the means to produce their own subsistence. More important that large-scale birth control programs are radical structural and institutional changes aimed at achieving social and economic progress and directly attacking poverty, unemployment, and inequality. Those countries where marked declines in birth rates have been achieved have usually been those that spread the benefits of development throughout their populations. Moreover, the Whitsun report implies that there is no family planning program in Zimbabwe. In fact, in 1982, an estimated 200,000 people received contraception through the Child Spacing and Fertility Association of Zimbabwe's program. It is unlikely that an expanded birth control program and educational campaign to persuade the rural and urban poor to practice family planning will be effective. Policy makers will have to address the cynicism brought about by the colonial regimes' genocidal efforts in the 1960s and 1970s to introduce birth control measures.

Human population reduction is not a quick fix for environmental problems.

PubMed

Bradshaw, Corey J A; Brook, Barry W

2014-11-18

The inexorable demographic momentum of the global human population is rapidly eroding Earth's life-support system. There are consequently more frequent calls to address environmental problems by advocating further reductions in human fertility. To examine how quickly this could lead to a smaller human population, we used scenario-based matrix modeling to project the global population to the year 2100. Assuming a continuation of current trends in mortality reduction, even a rapid transition to a worldwide one-child policy leads to a population similar to today's by 2100. Even a catastrophic mass mortality event of 2 billion deaths over a hypothetical 5-y window in the mid-21(st) century would still yield around 8.5 billion people by 2100. In the absence of catastrophe or large fertility reductions (to fewer than two children per female worldwide), the greatest threats to ecosystems--as measured by regional projections within the 35 global Biodiversity Hotspots--indicate that Africa and South Asia will experience the greatest human pressures on future ecosystems. Humanity's large demographic momentum means that there are no easy policy levers to change the size of the human population substantially over coming decades, short of extreme and rapid reductions in female fertility; it will take centuries, and the long-term target remains unclear. However, some reduction could be achieved by midcentury and lead to hundreds of millions fewer people to feed. More immediate results for sustainability would emerge from policies and technologies that reverse rising consumption of natural resources.

Multi-objective optimization in systematic conservation planning and the representation of genetic variability among populations.

PubMed

Schlottfeldt, S; Walter, M E M T; Carvalho, A C P L F; Soares, T N; Telles, M P C; Loyola, R D; Diniz-Filho, J A F

2015-06-18

Biodiversity crises have led scientists to develop strategies for achieving conservation goals. The underlying principle of these strategies lies in systematic conservation planning (SCP), in which there are at least 2 conflicting objectives, making it a good candidate for multi-objective optimization. Although SCP is typically applied at the species level (or hierarchically higher), it can be used at lower hierarchical levels, such as using alleles as basic units for analysis, for conservation genetics. Here, we propose a method of SCP using a multi-objective approach. We used non-dominated sorting genetic algorithm II in order to identify the smallest set of local populations of Dipteryx alata (baru) (a Brazilian Cerrado species) for conservation, representing the known genetic diversity and using allele frequency information associated with heterozygosity and Hardy-Weinberg equilibrium. We worked in 3 variations for the problem. First, we reproduced a previous experiment, but using a multi-objective approach. We found that the smallest set of populations needed to represent all alleles under study was 7, corroborating the results of the previous study, but with more distinct solutions. In the 2nd and 3rd variations, we performed simultaneous optimization of 4 and 5 objectives, respectively. We found similar but refined results for 7 populations, and a larger portfolio considering intra-specific diversity and persistence with populations ranging from 8-22. This is the first study to apply multi-objective algorithms to an SCP problem using alleles at the population level as basic units for analysis.

Gaining Access to Economically Marginalized Rural Populations: Lessons Learned from Nonprobability Sampling

ERIC Educational Resources Information Center

Mammen, Sheila; Sano, Yoshie

2012-01-01

Poverty is a significant problem in rural America. Gaining access to economically marginalized rural populations in order to recruit individuals to participate in a research study, however, is often a challenge. This article compares three different nonprobability sampling techniques that have been used to recruit rural, low-income…

Measuring Lead Exposure in Infants, Children, and Other Sensitive Populations.

ERIC Educational Resources Information Center

National Academy of Sciences - National Research Council, Washington, DC.

Adverse health effects from exposure to lead are now recognized to be among industrialized society's most important health problems. This report, prepared by the National Research Council's Committee on Measuring Lead Exposure in Critical Populations, concurs with new findings issued by the Centers for Disease Control which state that lead…

Diagnosing Alzheimer's Dementia in Down Syndrome: Problems and Possible Solutions

ERIC Educational Resources Information Center

Nieuwenhuis-Mark, Ruth E.

2009-01-01

It is widely accepted that people with Down syndrome are more likely than the general population to develop Alzheimer's dementia as they age. However, the diagnosis can be problematic in this population for a number of reasons. These include: the large intra-individual variability in cognitive functioning, the different diagnostic and…

Steelhead of the south-central/southern California coast: Population characterization for recovery planning

USGS Publications Warehouse

Boughton, David A.; Adams, P.B.; Anderson, E.; Fusaro, Craig; Keller, E.; Kelley, Elsie; Lentsch, Leo; Nielsen, J. L.; Perry, Katie; Regan, Helen; Swift, C.; Watson, Fred

2006-01-01

This report by the National Marine Fisheries Service applies a formal evaluation framework to the problem of delineating Oncorhynchus mykiss populations in the South-Central/Southern California Coast recovery domain, in support of recovery planning under the Endangered Species Act.

Obesity Rates in Special Populations of Children and Potential Interventions

ERIC Educational Resources Information Center

Holcomb, Matthew J.; Pufpaff, Lisa A.; McIntosh, David E.

2009-01-01

Childhood obesity has become a problem of epidemic proportions in the United States, but much of the research has focused on prevention and intervention programs, which target the general population of school children. Overlooked in the literature are children with special needs (including autism, genetic disorders, Down syndrome, and Prader-Willi…

The Effects of Finite Sampling on State Assessment Sample Requirements. NAEP Validity Studies. Working Paper Series.

ERIC Educational Resources Information Center

Chromy, James R.

This study addressed statistical techniques that might ameliorate some of the sampling problems currently facing states with small populations participating in State National Assessment of Educational Progress (NAEP) assessments. The study explored how the application of finite population correction factors to the between-school component of…

Optimizing habitat protection using demographic models of population viability.

Treesearch

Robert G. Haight; Brian Cypher; Patrick A. Kelly; Scott Phillips; Hugh P. Possingham; Katherine Ralls; Anthony M. Starfield; P.J. White; Daniel Williams

2002-01-01

Expanding habitat protection is a common tactic for species conservation. When unprotected habitat is privately owned, decisions must be made about which areas to protect by land purchase or conservation easement. To address this problem, we developed an optimization framework for choosing the habitat protection strategy that minimizes the risk of population extinction...

Silent Killer: A Study of Job Burnout in a Postsecondary Educational Setting

ERIC Educational Resources Information Center

Swagger, Russell M.

2010-01-01

The problem investigated was job burnout within postsecondary faculty populations. The study purpose was to test theory, add to the body of knowledge, and identify opportunities for effective intervention strategies that reduce job burnout within this population. The primary research question was what relationships exist between age and gender…

An Effectiveness Study of a Culturally Enriched School-Based CBT Anxiety Prevention Program

ERIC Educational Resources Information Center

Miller, Lynn D.; Laye-Gindhu, Aviva; Bennett, Joanna L.; Liu, Yan; Gold, Stephenie; March, John S.; Olson, Brent F.; Waechtler, Vanessa E.

2011-01-01

Anxiety disorders are prevalent in the school-aged population and are present across cultural groups. Scant research exists on culturally relevant prevention and intervention programs for mental health problems in the Aboriginal populations. An established cognitive behavioral program, FRIENDS for Life, was enriched to include content that was…

Rural Renaissance in America? The Revival of Population Growth in Remote Areas.

ERIC Educational Resources Information Center

Morrison, Peter A.; Wheeler, Judith P.

Presenting narrative and tabular documentation of the revival of population growth in remote, rural areas and the decline of growth in urban areas, this bulletin describes the characteristics of these shifts, considers their possible causes, and suggests some of the problems and potential benefits. Specifically, this report presents the following:…

Chronic Hepatitis C Infection in a Rural Medicaid HMO

ERIC Educational Resources Information Center

Calvert Jr., James F.; Goldenberg, Paula C.; Schock, Cathy

2005-01-01

Chronic hepatitis C infection (CHCI) is an increasingly common problem, affecting about 2% of the US population. The cost and complexity of treatment and difficulties in communicating with the infected population are of concern to insurers and health planners. Purpose: To describe the clinical features of patients with CHCI in a rural…

Examining Doctoral Students' Perceptions of Diversity in a Diversity Studies Specialization

ERIC Educational Resources Information Center

de Souza Correa, Daniel

2017-01-01

A recent challenge for contemporary education has been to efficiently educate the increasingly diverse American population (Holley, 2013). Seeking to resolve the problems related to the education of a diverse student population, colleges and universities across the United States have begun to require students to enroll in diversity courses…

An Oral Health Education Program for Latino Immigrant Parents

ERIC Educational Resources Information Center

Brown, Ruth M.; Canham, Daryl; Cureton, Virginia Young

2005-01-01

A high prevalence of dental caries in the pediatric population is a major health problem. At highest risk are low-income minority groups, including refugee and immigrant populations. Consequences of oral disease include pain, difficulty eating and speaking, poor school performance, and poor self-esteem. Parent involvement in oral health education…

Teacher's Study Guide on the Biology of Human Populations: Asia.

ERIC Educational Resources Information Center

United Nations Educational, Scientific, and Cultural Organization, Paris (France).

Factual and conceptual information dealing with the biology of human populations is offered in this guide for secondary science teachers. Instructional approaches are reviewed and suggestions are offered for use of the problem method approach, the discussion technique, and the project option. Information is organized into an introduction and five…

A Personality Development Interpretation of Employability and Disadvantaged Status with Remedial Implications: Counseling Services Report No. 21.

ERIC Educational Resources Information Center

Conrad, Rowan W.

Tracing problems observed among the Mountain-Plains student population, a trend of apparently improper or arrested personality development emerges. Observations indicate that a majority of the student population does not possess normally developed trust, autonomy, initiative, industry, sense of identity, or ability to develop intimate…

An Evaluation of Six Brief Interventions that Target Drug-Related Problems in Correctional Populations

ERIC Educational Resources Information Center

Joe, George W.; Knight, Kevin; Simpson, D. Dwayne; Flynn, Patrick M.; Morey, Janis T.; Bartholomew, Norma G.; Tindall, Michele Staton; Burdon, William M.; Hall, Elizabeth A.; Martin, Steve S.; O'Connell, Daniel J.

2012-01-01

Finding brief effective treatments for criminal justice populations is a major public need. The CJ-DATS Targeted Intervention for Corrections (TIC), which consists of six brief interventions (communication, anger, motivation, criminal thinking, social networks, and HIV/sexual health), was tested in separate federally-funded randomized control…

FAMILY AND MENTAL HEALTH PROBLEMS IN A DEAF POPULATION.

ERIC Educational Resources Information Center

RAINER, JOHN D., ED.; AND OTHERS

THE FINAL REPORT OF THE MENTAL HEALTH PROJECT FOR THE DEAF IS PRESENTED. FOLLOWING AN EXPLANATION OF THE PROJECT AND ITS PROCEDURES AND AN HISTORICAL REVIEW OF SPECIAL EDUCATION AND MENTAL HEALTH SERVICES ARE REPORTS (BY INDIVIDUAL AUTHORS) OF THE RESEARCH PROGRAM WITHIN THE NEW YORK STATE DEAF POPULATION, THE REPORTS CONSIDER (1) METHODOLOGICAL…

From Welfare to Work: The Transition of an Illiterate Population.

ERIC Educational Resources Information Center

Employment Policies Inst., Washington, DC.

With welfare reform now a reality, policy makers and employers must grapple with the employment impediments that keep much of the welfare population out of the work force. The foremost problem is illiteracy. One-third of welfare recipients are functionally illiterate; another third possesses only marginally better reading skills, still unable to…

Population Growth and Family Planning. IN Visitors' Information Special Report. SO 6.

ERIC Educational Resources Information Center

Heisse, Thomas

The rapid and still-accelerating increase in the world's population, especially in developing nations, will have a number of serious economic, social, and ecological consequences for the whole world. Germany is attempting to help solve these problems by providing family planning and poverty alleviation assistance to developing nations. German…

Incorporating Case Studies into a World Food and Population Course

ERIC Educational Resources Information Center

Econopouly, Bethany F.; Byrne, Patrick F.; Johnson, Marc A.

2010-01-01

The use of case studies in college courses can increase student engagement with the subject matter and improve analytical, problem-solving, and communication skills. Case studies were introduced in a relatively large (54 students) undergraduate world food and population course at Colorado State University in the spring semester of 2008 and…

Special Report on Dental Care for Handicapped People.

ERIC Educational Resources Information Center

Rehabilitation Services Administration (DHEW), Washington, DC.

The document presents a Department of Health, Education and Welfare (HEW) special report on dental care for the handicapped. The nature and extent of the problem of providing dental services to the handicapped population is examined. The handicapped population is defined and their oral health status reviewed. Factors contributing to the poor oral…

[Feminists' approach to population problems: new paradigm or Utopia?].

PubMed

Kono, S

1997-05-01

The author first notes that, partly because of events occurring at the International Conference on Population and Development that took place in Cairo in 1994, a consensus has emerged that population programs based on a philosophy of empowering women and focusing on reproductive health are more likely to be effective than programs that focus on providing family planning services and achieving demographic targets. Some reservations about this consensus are then expressed. The author points out the difficulties inherent in widening the mandate of family planning programs in an era of diminished resources for international assistance, the past success of such programs in reducing fertility with limited resources, and the inherent contradictions in following a laissez-faire attitude toward reproduction in such regions as Sub-Saharan Africa, where economies and political systems are often in crisis, health services are minimal, and desired levels of fertility both way above current levels and far above the replacement level. While not challenging the value of the Cairo philosophy, the need to move from rhetoric to reality in the face of the world's current population problems is stressed.

Altruism Can Proliferate through Population Viscosity despite High Random Gene Flow

PubMed Central

Schonmann, Roberto H.; Vicente, Renato; Caticha, Nestor

2013-01-01

The ways in which natural selection can allow the proliferation of cooperative behavior have long been seen as a central problem in evolutionary biology. Most of the literature has focused on interactions between pairs of individuals and on linear public goods games. This emphasis has led to the conclusion that even modest levels of migration would pose a serious problem to the spread of altruism through population viscosity in group structured populations. Here we challenge this conclusion, by analyzing evolution in a framework which allows for complex group interactions and random migration among groups. We conclude that contingent forms of strong altruism that benefits equally all group members, regardless of kinship and without greenbeard effects, can spread when rare under realistic group sizes and levels of migration, due to the assortment of genes resulting only from population viscosity. Our analysis combines group-centric and gene-centric perspectives, allows for arbitrary strength of selection, and leads to extensions of Hamilton’s rule for the spread of altruistic alleles, applicable under broad conditions. PMID:23991035

Genetic Diversity and Societally Important Disparities

PubMed Central

Rosenberg, Noah A.; Kang, Jonathan T. L.

2015-01-01

The magnitude of genetic diversity within human populations varies in a way that reflects the sequence of migrations by which people spread throughout the world. Beyond its use in human evolutionary genetics, worldwide variation in genetic diversity sometimes can interact with social processes to produce differences among populations in their relationship to modern societal problems. We review the consequences of genetic diversity differences in the settings of familial identification in forensic genetic testing, match probabilities in bone marrow transplantation, and representation in genome-wide association studies of disease. In each of these three cases, the contribution of genetic diversity to social differences follows from population-genetic principles. For a fourth setting that is not similarly grounded, we reanalyze with expanded genetic data a report that genetic diversity differences influence global patterns of human economic development, finding no support for the claim. The four examples describe a limit to the importance of genetic diversity for explaining societal differences while illustrating a distinction that certain biologically based scenarios do require consideration of genetic diversity for solving problems to which populations have been differentially predisposed by the unique history of human migrations. PMID:26354973

Statistical tools for analysis and modeling of cosmic populations and astronomical time series: CUDAHM and TSE

NASA Astrophysics Data System (ADS)

Loredo, Thomas; Budavari, Tamas; Scargle, Jeffrey D.

2018-01-01

This presentation provides an overview of open-source software packages addressing two challenging classes of astrostatistics problems. (1) CUDAHM is a C++ framework for hierarchical Bayesian modeling of cosmic populations, leveraging graphics processing units (GPUs) to enable applying this computationally challenging paradigm to large datasets. CUDAHM is motivated by measurement error problems in astronomy, where density estimation and linear and nonlinear regression must be addressed for populations of thousands to millions of objects whose features are measured with possibly complex uncertainties, potentially including selection effects. An example calculation demonstrates accurate GPU-accelerated luminosity function estimation for simulated populations of $10^6$ objects in about two hours using a single NVIDIA Tesla K40c GPU. (2) Time Series Explorer (TSE) is a collection of software in Python and MATLAB for exploratory analysis and statistical modeling of astronomical time series. It comprises a library of stand-alone functions and classes, as well as an application environment for interactive exploration of times series data. The presentation will summarize key capabilities of this emerging project, including new algorithms for analysis of irregularly-sampled time series.

Insight into alcohol-related problems and its associations with severity of alcohol consumption, mental health status, race, and level of acculturation in southern Taiwanese indigenous people with alcoholism.

PubMed

Yen, Cheng-Fang; Hsiao, Ray C; Ries, Richard; Liu, Shu-Chun; Huang, Chi-Fen; Chang, Yu-Ping; Yu, Ming-Lung

2008-01-01

While not well known in the West, Taiwan has a substantial indigenous population, and this population has rapidly developed alcohol problems. This study examined the level of insight into alcohol-related problems and its associations with the severity of alcohol consumption, mental health status, race, and the level of acculturation among indigenous populations with alcohol problems in southern Taiwan. A total of 332 indigenes, whose total Alcohol Use Disorders Identification Test (AUDIT) score was equal to 8 or higher, were interviewed. The associations between the level of insight into alcohol-related problems and the severity of alcohol drinking on the AUDIT, mental health status on the Chinese Health Questionnaire-12 (>or= 4 vs. < 4), race (Bunun vs. non-Bunun), and the level of acculturation on the Taiwan Aboriginal Acculturation Scale were examined using logistic regression models. The results of this study found that 72.6% of the participants had poor insight into alcohol-related problems and no participant had good insight. Participants who had more severe alcohol drinking or poor mental health were more likely to have a higher level of insight into alcohol-related problems. Participants who were non-Bunun were also more likely to have a higher level of insight into alcohol-related problems, but the level of acculturation was not associated with the level of insight into alcohol-related problems. These findings suggest that most alcoholic indigenes in southern Taiwan have poor insight into their own alcohol-related problems. Cultural specific interventions targeting and improving the indigenes' insight into alcohol-related problems are needed.

Complex Population Dynamics and the Coalescent Under Neutrality

PubMed Central

Volz, Erik M.

2012-01-01

Estimates of the coalescent effective population size Ne can be poorly correlated with the true population size. The relationship between Ne and the population size is sensitive to the way in which birth and death rates vary over time. The problem of inference is exacerbated when the mechanisms underlying population dynamics are complex and depend on many parameters. In instances where nonparametric estimators of Ne such as the skyline struggle to reproduce the correct demographic history, model-based estimators that can draw on prior information about population size and growth rates may be more efficient. A coalescent model is developed for a large class of populations such that the demographic history is described by a deterministic nonlinear dynamical system of arbitrary dimension. This class of demographic model differs from those typically used in population genetics. Birth and death rates are not fixed, and no assumptions are made regarding the fraction of the population sampled. Furthermore, the population may be structured in such a way that gene copies reproduce both within and across demes. For this large class of models, it is shown how to derive the rate of coalescence, as well as the likelihood of a gene genealogy with heterochronous sampling and labeled taxa, and how to simulate a coalescent tree conditional on a complex demographic history. This theoretical framework encapsulates many of the models used by ecologists and epidemiologists and should facilitate the integration of population genetics with the study of mathematical population dynamics. PMID:22042576

On the effects of nonlinear boundary conditions in diffusive logistic equations on bounded domains

NASA Astrophysics Data System (ADS)

Cantrell, Robert Stephen; Cosner, Chris

We study a diffusive logistic equation with nonlinear boundary conditions. The equation arises as a model for a population that grows logistically inside a patch and crosses the patch boundary at a rate that depends on the population density. Specifically, the rate at which the population crosses the boundary is assumed to decrease as the density of the population increases. The model is motivated by empirical work on the Glanville fritillary butterfly. We derive local and global bifurcation results which show that the model can have multiple equilibria and in some parameter ranges can support Allee effects. The analysis leads to eigenvalue problems with nonstandard boundary conditions.

Exploring first-order phase transitions with population annealing

NASA Astrophysics Data System (ADS)

Barash, Lev Yu.; Weigel, Martin; Shchur, Lev N.; Janke, Wolfhard

2017-03-01

Population annealing is a hybrid of sequential and Markov chain Monte Carlo methods geared towards the efficient parallel simulation of systems with complex free-energy landscapes. Systems with first-order phase transitions are among the problems in computational physics that are difficult to tackle with standard methods such as local-update simulations in the canonical ensemble, for example with the Metropolis algorithm. It is hence interesting to see whether such transitions can be more easily studied using population annealing. We report here our preliminary observations from population annealing runs for the two-dimensional Potts model with q > 4, where it undergoes a first-order transition.

International Health

MedlinePlus

... create refugee populations with immediate and long-term health problems. Some of the major diseases currently affecting ... also an international problem which can affect people's health. Many countries and health organizations are working together ...

Simulating the evolution of glyphosate resistance in grains farming in northern Australia

PubMed Central

Thornby, David F.; Walker, Steve R.

2009-01-01

Background and Aims The evolution of resistance to herbicides is a substantial problem in contemporary agriculture. Solutions to this problem generally consist of the use of practices to control the resistant population once it evolves, and/or to institute preventative measures before populations become resistant. Herbicide resistance evolves in populations over years or decades, so predicting the effectiveness of preventative strategies in particular relies on computational modelling approaches. While models of herbicide resistance already exist, none deals with the complex regional variability in the northern Australian sub-tropical grains farming region. For this reason, a new computer model was developed. Methods The model consists of an age- and stage-structured population model of weeds, with an existing crop model used to simulate plant growth and competition, and extensions to the crop model added to simulate seed bank ecology and population genetics factors. Using awnless barnyard grass (Echinochloa colona) as a test case, the model was used to investigate the likely rate of evolution under conditions expected to produce high selection pressure. Key Results Simulating continuous summer fallows with glyphosate used as the only means of weed control resulted in predicted resistant weed populations after approx. 15 years. Validation of the model against the paddock history for the first real-world glyphosate-resistant awnless barnyard grass population shows that the model predicted resistance evolution to within a few years of the real situation. Conclusions This validation work shows that empirical validation of herbicide resistance models is problematic. However, the model simulates the complexities of sub-tropical grains farming in Australia well, and can be used to investigate, generate and improve glyphosate resistance prevention strategies. PMID:19567415

Long-Term Health-Related Quality of Life in German Patients with Juvenile Idiopathic Arthritis in Comparison to German General Population

PubMed Central

Barth, Swaantje; Haas, Johannes-Peter; Schlichtiger, Jenny; Molz, Johannes; Bisdorff, Betty; Michels, Hartmut; Hügle, Boris; Radon, Katja

2016-01-01

Objective Aims of the study were to investigate health-related quality of life (HRQOL) in adult patients with former diagnosis of Juvenile Idiopathic Arthritis (JIA), to compare their HRQOL with the general population and to identify factors related to a poor outcome. Methods In 2012, a cross-sectional survey was performed by mailing a questionnaire to a large cohort of former and current patients of the German Centre for Rheumatology in Children and Adolescents. Only adult patients (≥18 years) with a diagnosis compatible with JIA were included (n = 2592; response 66%). The questionnaire included information about HRQOL (EQ5D), disease-related questions and socio-demographics. Prevalence and 95% confidence intervals (CI) of problems with mobility, self-care, usual activities, pain and anxiety/depression were standardized to the German general population. Factors associated with low HRQOL in JIA patients were identified using logistic regression models. Results Sixty-two percent of the study population was female; age range was 18–73 years. In all dimensions, JIA patients reported statistically significantly more problems than the general population with largest differences in the pain dimension (JIA patients 56%; 95%CI 55–58%; general population 28%; 26–29%) and the anxiety/depression dimension (28%; 27–29% vs. 4%; 4–5%). Lower HRQOL in JIA patients was associated with female sex, older age, lower level of education, still being under rheumatic treatment and disability. Conclusions HRQOL in adult JIA patients is considerably lower than in the general population. As this cohort includes historic patients the new therapeutic schemes available today are expected to improve HRQOL in future. PMID:27115139

22q11.2 deletion syndrome in diverse populations.

PubMed

Kruszka, Paul; Addissie, Yonit A; McGinn, Daniel E; Porras, Antonio R; Biggs, Elijah; Share, Matthew; Crowley, T Blaine; Chung, Brian H Y; Mok, Gary T K; Mak, Christopher C Y; Muthukumarasamy, Premala; Thong, Meow-Keong; Sirisena, Nirmala D; Dissanayake, Vajira H W; Paththinige, C Sampath; Prabodha, L B Lahiru; Mishra, Rupesh; Shotelersuk, Vorasuk; Ekure, Ekanem Nsikak; Sokunbi, Ogochukwu Jidechukwu; Kalu, Nnenna; Ferreira, Carlos R; Duncan, Jordann-Mishael; Patil, Siddaramappa Jagdish; Jones, Kelly L; Kaplan, Julie D; Abdul-Rahman, Omar A; Uwineza, Annette; Mutesa, Leon; Moresco, Angélica; Obregon, María Gabriela; Richieri-Costa, Antonio; Gil-da-Silva-Lopes, Vera L; Adeyemo, Adebowale A; Summar, Marshall; Zackai, Elaine H; McDonald-McGinn, Donna M; Linguraru, Marius George; Muenke, Maximilian

2017-04-01

22q11.2 deletion syndrome (22q11.2 DS) is the most common microdeletion syndrome and is underdiagnosed in diverse populations. This syndrome has a variable phenotype and affects multiple systems, making early recognition imperative. In this study, individuals from diverse populations with 22q11.2 DS were evaluated clinically and by facial analysis technology. Clinical information from 106 individuals and images from 101 were collected from individuals with 22q11.2 DS from 11 countries; average age was 11.7 and 47% were male. Individuals were grouped into categories of African descent (African), Asian, and Latin American. We found that the phenotype of 22q11.2 DS varied across population groups. Only two findings, congenital heart disease and learning problems, were found in greater than 50% of participants. When comparing the clinical features of 22q11.2 DS in each population, the proportion of individuals within each clinical category was statistically different except for learning problems and ear anomalies (P < 0.05). However, when Africans were removed from analysis, six additional clinical features were found to be independent of ethnicity (P ≥ 0.05). Using facial analysis technology, we compared 156 Caucasians, Africans, Asians, and Latin American individuals with 22q11.2 DS with 156 age and gender matched controls and found that sensitivity and specificity were greater than 96% for all populations. In summary, we present the varied findings from global populations with 22q11.2 DS and demonstrate how facial analysis technology can assist clinicians in making accurate 22q11.2 DS diagnoses. This work will assist in earlier detection and in increasing recognition of 22q11.2 DS throughout the world. © 2017 Wiley Periodicals, Inc.

HIV/AIDS Related Stigma and Discrimination against PLWHA in Nigerian Population

PubMed Central

Bulgiba, Awang; Oche, Oche Mansur; Adekunjo, Felix Oluyemi

2015-01-01

Background HIV/AIDS remain a major public health concern in Nigeria. People living with HIV/AIDS (PLWHA) face not only personal medical problems but also social problems associated with the disease such as stigma and discriminatory attitudes. This study provides an insight into HIV/AIDS related stigma and discrimination against PLWHA in Nigeria. Methods The data for this study was extracted from the 2013 Nigeria Demographic and Health Survey conducted by the National Population Commission. All men and women aged 15–49 years, permanent residents and visitors of the households were eligible for the interview. Several questionnaires were used in the survey, some covering questions on HIV/AIDS. Results A total of 56 307 men and women aged 15–49 years participated in this national survey. About half of the population in Nigeria have HIV stigma. Younger persons, men, those without formal education and those within poor wealth index are more likely to have stigma towards PLWHA. In addition, married people are more likely to have stigma on PLWHA and are more likely to blame PLWHA for bringing the disease to the community. Also about half of the population discriminates against PLWHA. However, those with higher levels of education and those from higher wealth index seem to be more compassionate towards PLWHA. About 70% in the population are willing to care for relative with AIDS, even more so among those with higher level of education. Conclusion There is a high level of HIV stigma and discrimination against PLWHA in the Nigerian population. Education seems to play a major role in the society with respect to HIV stigma and discrimination against PLWHA. Educating the population with factual information on HIV/AIDS is needed to reduce stigma and discrimination towards PLWHA in the community. PMID:26658767

HIV/AIDS Related Stigma and Discrimination against PLWHA in Nigerian Population.

PubMed

Dahlui, Maznah; Azahar, Nazar; Bulgiba, Awang; Zaki, Rafdzah; Oche, Oche Mansur; Adekunjo, Felix Oluyemi; Chinna, Karuthan

2015-01-01

HIV/AIDS remain a major public health concern in Nigeria. People living with HIV/AIDS (PLWHA) face not only personal medical problems but also social problems associated with the disease such as stigma and discriminatory attitudes. This study provides an insight into HIV/AIDS related stigma and discrimination against PLWHA in Nigeria. The data for this study was extracted from the 2013 Nigeria Demographic and Health Survey conducted by the National Population Commission. All men and women aged 15-49 years, permanent residents and visitors of the households were eligible for the interview. Several questionnaires were used in the survey, some covering questions on HIV/AIDS. A total of 56 307 men and women aged 15-49 years participated in this national survey. About half of the population in Nigeria have HIV stigma. Younger persons, men, those without formal education and those within poor wealth index are more likely to have stigma towards PLWHA. In addition, married people are more likely to have stigma on PLWHA and are more likely to blame PLWHA for bringing the disease to the community. Also about half of the population discriminates against PLWHA. However, those with higher levels of education and those from higher wealth index seem to be more compassionate towards PLWHA. About 70% in the population are willing to care for relative with AIDS, even more so among those with higher level of education. There is a high level of HIV stigma and discrimination against PLWHA in the Nigerian population. Education seems to play a major role in the society with respect to HIV stigma and discrimination against PLWHA. Educating the population with factual information on HIV/AIDS is needed to reduce stigma and discrimination towards PLWHA in the community.

[Population growth and the environment].

PubMed

Hogan, D J

1991-01-01

The impact of population growth on the enviornment has been extensively researched; it consists of the depletion of resources (agricultural land absorbed by urban expansion, loss of soils, desertification, loss of biodiversity, less availability of minerals, dwindling of petroleum reserves) and the degradation of natural resources (air and water pollution). For politicians, journalists, and environmentalists, population growth is identified as the principal villain, which is a unidirectional and negative opinion. Demography is supposed to examine the negative and positive effects of the environment-population relationship; however, it is postulated that there has not been much produced in the last 2 centuries in this area. Examination of the research literature does not indicate any view that transcends the Malthusian vision, although a few empirical studies exist (Hogan, 1989). Durham (1979) identified the replacement of subsistence agriculture by export-oriented agriculture as the key factor in overpopulation in El Salvador and Honduras that led to migrations and international conflicts. Tudela (1987) related a similar process in the Mexican state of Tabasco, where a period of malnutrition was accompanied by the expansion of export agriculture and nutritional improvements emanated only from recapturing subsistence agriculture. Fearnside (1986) researched the dynamics of the occupation and destruction of Amazonia. However, Kahn and Simon went further and denied the existence of real environmental problems: population is the ultimate resource, and the more minds, the more good ideas and solutions for any problem. However, in all these cases of pure or modified Malthusianism the relation of population/resources is reduced to a unidimensional relationship; and fertility, mortality, migration, marriage, and age structure receive little attention. A prime candidate for the attention of population specialists should be migration and patterns of settlement and their relationships to the physical environment, aspects of the depletion and degradation of resources as well as socially useful alterations.

Computer re-sampling for demographically representative user populations in anthropometry: a case of doorway and clear floor space widths.

PubMed

Paquet, Victor; Joseph, Caroline; D'Souza, Clive

2012-01-01

Anthropometric studies typically require a large number of individuals that are selected in a manner so that demographic characteristics that impact body size and function are proportionally representative of a user population. This sampling approach does not allow for an efficient characterization of the distribution of body sizes and functions of sub-groups within a population and the demographic characteristics of user populations can often change with time, limiting the application of the anthropometric data in design. The objective of this study is to demonstrate how demographically representative user populations can be developed from samples that are not proportionally representative in order to improve the application of anthropometric data in design. An engineering anthropometry problem of door width and clear floor space width is used to illustrate the value of the approach.

Status of India's population education programme--the subject of tripartite projects review and annual country review.

PubMed

1981-12-01

A 3-step monitoring of India's population education program was undertaken in 1981 in order to determine the level of implementation and progress of the program. This monitoring program, conducted by the Unesco Mobile Team in collaboration with other institutions, followed 3 procedures: Project Progress Report (PPR); Tripartite Project Review (TPR); and Annual Country Review (ACR). The review meetings of the 10 state population education projects were organized at Chandigarh and Madras during August. The states covered in the review were Bihar, Haryana, Madhaya Pradesh, Punjab, Rajasthan, Chandigarh, Gujarat, Karnataka, Maharashtra, and Tamil Nadu. The Tripartite Review identified the following as problems which were hindering the smooth implementation of the population education program: 1) difficulty in spending funds unless certain formalities were completed by the governments of the states; 2) administrative problems such as getting printing paper for instructional materials, waiving the sales tax for equipment to be purchased under the project, and uncertainty regarding the admissible rates of per diem to be paid to the participants in various training programs; 3) the lack of experience of project staff; 4) problems created by having more than 1 cell in a state such as Rajasthan; and 5) an inadequate time frame within which the project should complete all its activities and make population education an integral part of the school system. The following were among the recommendations made: 1) the Project should be made coterminous with the 6th Five-Year Plan up to March 31, 1985; and 2) there should be only 1 Population Education Cell in every state. Among the points discussed at the annual country review, held during October, were the following: rephasing of the program from a 3 to 5 year project to synchronize it with the 6th plan; and the need for additional funds in view of inflation.

Solving Man-Induced Large-Scale Conservation Problems: The Spanish Imperial Eagle and Power Lines

PubMed Central

López-López, Pascual; Ferrer, Miguel; Madero, Agustín; Casado, Eva; McGrady, Michael

2011-01-01

Background Man-induced mortality of birds caused by electrocution with poorly-designed pylons and power lines has been reported to be an important mortality factor that could become a major cause of population decline of one of the world rarest raptors, the Spanish imperial eagle (Aquila adalberti). Consequently it has resulted in an increasing awareness of this problem amongst land managers and the public at large, as well as increased research into the distribution of electrocution events and likely mitigation measures. Methodology/Principal Findings We provide information of how mitigation measures implemented on a regional level under the conservation program of the Spanish imperial eagle have resulted in a positive shift of demographic trends in Spain. A 35 years temporal data set (1974–2009) on mortality of Spanish imperial eagle was recorded, including population censuses, and data on electrocution and non-electrocution of birds. Additional information was obtained from 32 radio-tracked young eagles and specific field surveys. Data were divided into two periods, before and after the approval of a regional regulation of power line design in 1990 which established mandatory rules aimed at minimizing or eliminating the negative impacts of power lines facilities on avian populations. Our results show how population size and the average annual percentage of population change have increased between the two periods, whereas the number of electrocuted birds has been reduced in spite of the continuous growing of the wiring network. Conclusions Our results demonstrate that solving bird electrocution is an affordable problem if political interest is shown and financial investment is made. The combination of an adequate spatial planning with a sustainable development of human infrastructures will contribute positively to the conservation of the Spanish imperial eagle and may underpin population growth and range expansion, with positive side effects on other endangered species. PMID:21399692

Memory-related subjective cognitive symptoms in the adult population: prevalence and associated factors - results of the LIFE-Adult-Study.

PubMed

Luck, Tobias; Roehr, Susanne; Rodriguez, Francisca S; Schroeter, Matthias L; Witte, A Veronica; Hinz, Andreas; Mehnert, Anja; Engel, Christoph; Loeffler, Markus; Thiery, Joachim; Villringer, Arno; Riedel-Heller, Steffi G

2018-05-21

Subjectively perceived memory problems (memory-related Subjective Cognitive Symptoms/SCS) can be an indicator of a pre-prodromal or prodromal stage of a neurodegenerative disease such as Alzheimer's disease. We therefore sought to provide detailed empirical information on memory-related SCS in the dementia-free adult population including information on prevalence rates, associated factors and others. We studied 8834 participants (40-79 years) of the population-based LIFE-Adult-Study. Weighted prevalence rates with confidence intervals (95%-CI) were calculated. Associations of memory-related SCS with participants' socio-demographic characteristics, physical and mental comorbidity, and cognitive performance (Verbal Fluency Test Animals, Trail-Making-Test, CERAD Wordlist tests) were analyzed. Prevalence of total memory-related SCS was 53.0% (95%-CI = 51.9-54.0): 26.0% (95%-CI = 25.1-27.0) of the population had a subtype without related concerns, 23.6% (95%-CI = 22.7-24.5) a subtype with some related concerns, and 3.3% (95%-CI = 2.9-3.7) a subtype with strong related concerns. Report of memory-related SCS was unrelated to participants' socio-demographic characteristics, physical comorbidity (except history of stroke), depressive symptomatology, and anxiety. Adults with and without memory-related SCS showed no significant difference in cognitive performance. About one fifth (18.1%) of the participants with memory-related SCS stated that they did consult/want to consult a physician because of their experienced memory problems. Memory-related SCS are very common and unspecific in the non-demented adult population aged 40-79 years. Nonetheless, a substantial proportion of this population has concerns related to experienced memory problems and/or seeks help. Already available information on additional features associated with a higher likelihood of developing dementia in people with SCS may help clinicians to decide who should be monitored more closely.

Poor oral health as an obstacle to employment for Medicaid beneficiaries with disabilities.

PubMed

Hall, Jean P; Chapman, Shawna L Carroll; Kurth, Noelle K

2013-01-01

To inform policy with better information about the oral health-care needs of a Medicaid population that engages in employment, that is, people ages 16 to 64 with Social Security-determined disabilities enrolled in a Medicaid Buy-In program. Statistically test for significant differences among responses to a Medicaid Buy-In program satisfaction survey that included oral health questions from the Centers for Disease Control and Prevention's Behavioral Risk Factor Surveillance System and the Oral Health Impact Profile (OHIP) to results for the state's general population and the US general population. All measures of dental care access and oral health were significantly worse for the study population as compared with a state general population or a US general population. Differences were particularly pronounced for the OHIP measure for difficulty doing one's job due to dental problems, which was almost five times higher for the study population. More comprehensive dental benefits for the study population could result in increased oral and overall health, and eventual cost savings to Medicaid as more people work, have improved health, and pay premiums for coverage. © 2012 American Association of Public Health Dentistry.

China's Population Policy at the Crossroads: Social Impacts and Prospects

PubMed Central

Jiang, Quanbao; Li, Shuzhuo; Feldman, Marcus W.

2015-01-01

China's total fertility rate fell below replacement level in the 1990s. From the 1970s the fertility rate declined dramatically, mainly as a consequence of the national population policy whose aim has been to limit birth numbers, control population growth and boost economic growth. Having achieved such a low fertility rate, how will China's population policy evolve in the future? This paper first reviews the history of China's population policy since 1970 in terms of three stages: 1970-1979; 1980-1999; and after 2000. We explore the impacts of China's population policy, including relief of pressure on China's environment and resources, fertility decline, the unexpectedly high male-biased sex ratio at birth (SRB), the coming shortage of labor force, and the rapid aging of the population. We also investigate ethical issues raised by the implementation of the policy and its results. Finally we introduce the controversy over potential adjustment of the policy, acknowledging the problems faced by western countries with low fertility and countermeasures they have taken. We offer some suggestions that might be appropriate in the Chinese context. PMID:26612983

Galactic civilizations - Population dynamics and interstellar diffusion

NASA Technical Reports Server (NTRS)

Newman, W. I.; Sagan, C.

1981-01-01

A model is developed of the interstellar diffusion of galactic civilizations which takes into account the population dynamics of such civilizations. The problem is formulated in terms of potential theory, with a family of nonlinear partial differential and difference equations specifying population growth and diffusion for an organism with advantageous genes that undergoes random dispersal while increasing in population locally, and a population at zero population growth. In the case of nonlinear diffusion with growth and saturation, it is found that the colonization wavefront from the nearest independently arisen galactic civilization can have reached the earth only if its lifetime exceeds 2.6 million years, or 20 million years if discretization can be neglected. For zero population growth, the corresponding lifetime is 13 billion years. It is concluded that the earth is uncolonized not because interstellar spacefaring civilizations are rare, but because there are too many worlds to be colonized in the plausible colonization lifetime of nearby civilizations, and that there exist no very old galactic civilizations with a consistent policy of the conquest of inhabited worlds.

Towards the Development of a More Accurate Monitoring Procedure for Invertebrate Populations, in the Presence of an Unknown Spatial Pattern of Population Distribution in the Field

PubMed Central

Petrovskaya, Natalia B.; Forbes, Emily; Petrovskii, Sergei V.; Walters, Keith F. A.

2018-01-01

Studies addressing many ecological problems require accurate evaluation of the total population size. In this paper, we revisit a sampling procedure used for the evaluation of the abundance of an invertebrate population from assessment data collected on a spatial grid of sampling locations. We first discuss how insufficient information about the spatial population density obtained on a coarse sampling grid may affect the accuracy of an evaluation of total population size. Such information deficit in field data can arise because of inadequate spatial resolution of the population distribution (spatially variable population density) when coarse grids are used, which is especially true when a strongly heterogeneous spatial population density is sampled. We then argue that the average trap count (the quantity routinely used to quantify abundance), if obtained from a sampling grid that is too coarse, is a random variable because of the uncertainty in sampling spatial data. Finally, we show that a probabilistic approach similar to bootstrapping techniques can be an efficient tool to quantify the uncertainty in the evaluation procedure in the presence of a spatial pattern reflecting a patchy distribution of invertebrates within the sampling grid. PMID:29495513

[Burkina Faso: review of population policies and programs].

PubMed

Kano, H

1999-12-01

When Burkina Faso gained its independence, no one thought to act upon the various demographic variables with the aim of achieving certain specific, planned goals. It was necessary to wait until 1986 for the adoption of a planning policy and the abrogation of part of 1920 legislation on contraceptive distribution before the first signs of attitudinal change could be observed with regard to population concerns. Formerly confused with birth limiting policy, family planning is increasingly becoming an essential component of maternal and infant health. The author describes the evolution of population policies in Burkina Faso from independence, after the 1974 Bucharest conference on population, and up until now. Today, general population policy goals in Burkina Faso are in favor of whatever will improve quality of life and well-being across all social strata. This goal will only be attained through the establishment of better balance between population and available resources. It involves meeting the population¿s essential food, nutrition, health, education, and employment needs; raising the value of available human resources; lowering morbidity and mortality; improving women¿s status; improving the population¿s spatial distribution; managing the environment better; and accounting for demographic variables when establishing development goals. Burkina Faso therefore plans to pursue a comprehensive approach toward its population problems.

Recent Studies on Feeding Problems in Children with Autism

ERIC Educational Resources Information Center

Volkert, Valerie M.; Vaz, Petula C. M.

2010-01-01

This paper reviews recent studies on behavioral interventions for children with autism and feeding problems. The applicability of interventions that have been tested with other populations of children with feeding problems is discussed, as well as directions for future research.

Gambling problems in the family--a stratified probability sample study of prevalence and reported consequences.

PubMed

Wenzel, Hanne Gro; Oren, Anita; Bakken, Inger Johanne

2008-12-16

Prior studies on the impact of problem gambling in the family mainly include help-seeking populations with small numbers of participants. The objective of the present stratified probability sample study was to explore the epidemiology of problem gambling in the family in the general population. Men and women 16-74 years-old randomly selected from the Norwegian national population database received an invitation to participate in this postal questionnaire study. The response rate was 36.1% (3,483/9,638). Given the lack of validated criteria, two survey questions ("Have you ever noticed that a close relative spent more and more money on gambling?" and "Have you ever experienced that a close relative lied to you about how much he/she gambles?") were extrapolated from the Lie/Bet Screen for pathological gambling. Respondents answering "yes" to both questions were defined as Concerned Significant Others (CSOs). Overall, 2.0% of the study population was defined as CSOs. Young age, female gender, and divorced marital status were factors positively associated with being a CSO. CSOs often reported to have experienced conflicts in the family related to gambling, worsening of the family's financial situation, and impaired mental and physical health. Problematic gambling behaviour not only affects the gambling individual but also has a strong impact on the quality of life of family members.

Gambling problems in the family – A stratified probability sample study of prevalence and reported consequences

PubMed Central

Wenzel, Hanne Gro; Øren, Anita; Bakken, Inger Johanne

2008-01-01

Background Prior studies on the impact of problem gambling in the family mainly include help-seeking populations with small numbers of participants. The objective of the present stratified probability sample study was to explore the epidemiology of problem gambling in the family in the general population. Methods Men and women 16–74 years-old randomly selected from the Norwegian national population database received an invitation to participate in this postal questionnaire study. The response rate was 36.1% (3,483/9,638). Given the lack of validated criteria, two survey questions ("Have you ever noticed that a close relative spent more and more money on gambling?" and "Have you ever experienced that a close relative lied to you about how much he/she gambles?") were extrapolated from the Lie/Bet Screen for pathological gambling. Respondents answering "yes" to both questions were defined as Concerned Significant Others (CSOs). Results Overall, 2.0% of the study population was defined as CSOs. Young age, female gender, and divorced marital status were factors positively associated with being a CSO. CSOs often reported to have experienced conflicts in the family related to gambling, worsening of the family's financial situation, and impaired mental and physical health. Conclusion Problematic gambling behaviour not only affects the gambling individual but also has a strong impact on the quality of life of family members. PMID:19087339

Gambling Harm and Crime Careers.

PubMed

May-Chahal, Corinne; Humphreys, Leslie; Clifton, Alison; Francis, Brian; Reith, Gerda

2017-03-01

Incarcerated populations across the world have been found to be consistently and significantly more vulnerable to problem gambling than general populations in the same countries. In an effort to gain a more specific understanding of this vulnerability the present study applied latent class analysis and criminal career theory to gambling data collected from a sample of English and Scottish, male and female prisoners (N = 1057). Theoretical links between gambling and crime were tested through three hypotheses: (1) that prisoners in the UK would have higher rates of problem gambling behaviour than the national population; (2) that if the link between gambling and crime is coincidental, gambling behaviour would be highly prevalent in an offending population, and (3) if connections between gambling behaviour and offending are co-symptomatic a mediating factor would show a strong association. The first of these was supported, the second was not supported and the third was partially supported. Latent class analysis found six gambling behaviour clusters measured by responses to the Problem Gambling Severity Index, primarily distinguished by loss chasing behaviour. Longitudinal offending data drawn from the Police National Computer database found four criminal career types, distinguished by frequency and persistence over time. A significant association was found between higher level loss chasing and high rate offending in criminal careers suggesting that impulse control may be a mediating factor for both gambling harm and criminal careers.

Editorial: 2nd Special Issue on behavior change, health, and health disparities.

PubMed

Higgins, Stephen T

2015-11-01

This Special Issue of Preventive Medicine (PM) is the 2nd that we have organized on behavior change, health, and health disparities. This is a topic of fundamental importance to improving population health in the U.S. and other industrialized countries that are trying to more effectively manage chronic health conditions. There is broad scientific consensus that personal behavior patterns such as cigarette smoking, other substance abuse, and physical inactivity/obesity are among the most important modifiable causes of chronic disease and its adverse impacts on population health. As such behavior change needs to be a key component of improving population health. There is also broad agreement that while these problems extend across socioeconomic strata, they are overrepresented among more economically disadvantaged populations and contribute directly to the growing problem of health disparities. Hence, behavior change represents an essential step in curtailing that unsettling problem as well. In this 2nd Special Issue, we devote considerable space to the current U.S. prescription opioid addiction epidemic, a crisis that was not addressed in the prior Special Issue. We also continue to devote attention to the two largest contributors to preventable disease and premature death, cigarette smoking and physical inactivity/obesity as well as risks of co-occurrence of these unhealthy behavior patterns. Across each of these topics we included contributions from highly accomplished policy makers and scientists to acquaint readers with recent accomplishments as well as remaining knowledge gaps and challenges to effectively managing these important chronic health problems. Copyright © 2015 Elsevier Inc. All rights reserved.

Dental and Oral Problem Patterns and Treatment Seeking Behavior of Geriatric Population

PubMed Central

AlZarea, Bader K.

2017-01-01

Background: The manifestations of oral changes and disorders affecting the geriatric population are different from the rest of the population. Inaccessibility to dental care is a compelling impediment to avail oral health services. Objective: The aims were to assess the dental and oral problems and to find out the determinants of oral health seeking behaviour among elderly population of Al-Jouf province, Saudi Arabia. Methods: The present cross sectional study included geriatric patients of 60 years and above, who visited the College of Dentistry, Al-Jouf University. A simple pre-structured questionnaire was filled by the patients, which comprised of demographic details and the different oral complaints of elderly and the type of health care utilized for those complaints. Results: Out of total 892 elderly persons included, 51.79% were males and 48.21 were females. The most common oral problem was missing tooth (78.69%) followed by gum problems (74.21%). 39.5% males and 28.0% females visited general dental practitioners for oral health care. Majority of the participants (32.8%) suggested accessibility as a basic factor in determining the health care source. The difference in the distribution of male and females or association between the type of care and gender and distribution for choosing a health care source was found to be statistically significant (p < 0.05). Conclusion: Inaccessibility to dental care emerged as an important barrier to avail oral health services. Adequate access to medical and dental care can reduce premature morbidity and mortality, preserve function, and enhance overall quality of life. PMID:28553412

Nurse Scheduling by Cooperative GA with Effective Mutation Operator

NASA Astrophysics Data System (ADS)

Ohki, Makoto

In this paper, we propose an effective mutation operators for Cooperative Genetic Algorithm (CGA) to be applied to a practical Nurse Scheduling Problem (NSP). The nurse scheduling is a very difficult task, because NSP is a complex combinatorial optimizing problem for which many requirements must be considered. In real hospitals, the schedule changes frequently. The changes of the shift schedule yields various problems, for example, a fall in the nursing level. We describe a technique of the reoptimization of the nurse schedule in response to a change. The conventional CGA is superior in ability for local search by means of its crossover operator, but often stagnates at the unfavorable situation because it is inferior to ability for global search. When the optimization stagnates for long generation cycle, a searching point, population in this case, would be caught in a wide local minimum area. To escape such local minimum area, small change in a population should be required. Based on such consideration, we propose a mutation operator activated depending on the optimization speed. When the optimization stagnates, in other words, when the optimization speed decreases, the mutation yields small changes in the population. Then the population is able to escape from a local minimum area by means of the mutation. However, this mutation operator requires two well-defined parameters. This means that user have to consider the value of these parameters carefully. To solve this problem, we propose a periodic mutation operator which has only one parameter to define itself. This simplified mutation operator is effective over a wide range of the parameter value.

Age-related aspects of addiction

PubMed Central

Koechl, Birgit; Unger, Annemarie; Fischer, Gabriele

2013-01-01

Research has shown that substance use, abuse and addiction are not limited to a specific age group. Problems related to substance addiction are an important cause of morbidity in the population aged 65 and above, especially the abuse of prescription drugs and legal substances. A lack of evidence-based studies and tailored treatment options for the aging population is evident. Appropriate and effective health-care is an important goal to improve health-related quality of life of elderly people. Research in the increasingly aging population needs to include an age- and gender-sensitive approach. PMID:22722821

"Stop, You’re Killing us!" An Alternative Take on Populism and Public Health

PubMed Central

Schrecker, Ted

2017-01-01

Ewen Speed and Russell Mannion correctly identify several contours of the challenges for health policy in what it is useful to think of as a post-democratic era. I argue that the problem for public health is not populism per se, but rather the distinctive populism of the right coupled with the failure of the left to develop compelling counternarratives. Further, defences of ‘science’ must be tempered by recognition of the unavoidably political dimensions of the (mis)use of scientific findings in public policy. PMID:29179294

Emergency Department Use for Dental Problems among Homeless Individuals: A Population-Based Cohort Study.

PubMed

Figueiredo, Rafael; Dempster, Laura; Quiñonez, Carlos; Hwang, Stephen W

2016-01-01

To evaluate emergency department (ED) visits for dental problems among Toronto's homeless population (Ontario, Canada). A random sample of 1,189 homeless was recruited from shelters and meal programs. Emergency department visits for non-traumatic dental problems (ICD-10-CA codes K00-K14) were identified using participants' health insurance number, during 2005-2009. Age- and sex-matched controls were selected from low-income neighborhoods. Homeless and matched controls had 182 and 10 ED visits for dental problems, respectively. Homeless people were more significantly more likely (OR=2.27, p=.007) to make ED visit for dental problems compared with controls. Over 80% of the ED visits by homeless people were for odontogenic infections, and 46% of homeless people had more than one such visit. The high rate of ED visits for dental problems by people who are homeless suggests that access to dental care is inadequate. The large number of repeat visits indicates that ED settings are ineffective for treatment of dental problems.

The invisible hand in San Francisco.

PubMed

Adams, J; Bouvier, L; Davis, C; Gardner, B; Haupt, A; Kent, M; Molajo, D; Merrick, T; Scully, J; Van Der Tak, J

1986-05-01

Over 1000 population enthusiasts found their way to San Francisco for the 1986 meetings of the Population Association of America (PAA) April 3-5. 2 pre-meetings included: 1) the Association for Population/Family Planning Libraries and Information Centers-International (APLIC), and 2) the psychosocial workshop. Sexual activity was a major topic of the session on "Fertility: Early and Late." Further investigation of the effects of marriage and fertility on behavior was reviewed in a session entitled "Trends in Household Composition and Living Arrangements." The session "Demography of Crime and Justice" gave the demographic answer to such questions as: Is the crime rate really falling? Opinions in a panel on the future of US international population policy were sharply divided; Agency for International Development representative Alison Rosenberg outlined the re-examination of the Agency's population program that had taken place since the population conference in Mexico City in 1984. The Presidential Address was preceded by the annual awards ceremony. PAA President Paul Demeny focused on an issue that has been at the core of the debate about whether population has good, bad, indifferent, or indeterminate effects on economic development: the extent to which society can entrust the solution of population problems to market forces. This year's PAA meeting echoed growing concern in the population field about low fertility in the more developed world as well as increasing skepticism over the negative consequences of rapid developing country population growth.

Population health and medicine: Policy and financial drivers.

PubMed

Lavigne, Jill E; Brown, Jack; Matzke, Gary R

2017-09-15

The financial and policy levers of population health and potential opportunities for pharmacists are described. Three long-standing problems drive the focus on population health: (1) the United States suffers far worse population health outcomes compared with those of other developed nations that spend significantly less on healthcare, (2) the U.S. healthcare system's focus on "sick care" fails to address upstream prevention and population health improvement, and (3) financial incentives for healthcare delivery are poorly aligned with improvements in population health outcomes. The Patient Protection and Affordable Care Act of 2010 (ACA) was arguably the first major healthcare legislation since 1965 and had 3 main strategies for improving population health: expand health insurance coverage, control healthcare costs, and improve the healthcare delivery system. Federal and state legislation as well as Medicare and Medicaid financing strategies have designated mechanisms to reward advances in population outcomes since the passage of the ACA. States are responsible for many of the factors that affect population health, and a bipartisan effort that builds upon state and federal collaboration will likely be needed to implement the necessary health policy initiative. Population health issues affect productivity in the United States; conversely, improvements in population health may increase productivity, helping to offset the rising federal debt. Employers are in a position to improve population health and consequently help reduce the federal debt by addressing lifestyle, chronic disease, poverty, and inequality. National pharmacy organizations, regulatory bodies, and journal editors need to collectively agree to a threshold of quality and rigor for publication and endorsement. Knowledge of the policy and financial drivers of population health may both support pharmacists' efforts to improve population outcomes and identify opportunities for professional advancement. Copyright © 2017 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Population and women's health.

PubMed

Abernethy, V

1994-01-01

Explanations of cultural patterns can be found in the economic context (carrying capacity) in which they develop. Population pressure explains the abuse of women throughout history and in modern times because overpopulation leads to devaluation of women's reproductive capacity. A cultural response to overpopulation includes practices that limit the numbers of women of reproductive age. Such practices foster son preference, which results in selective abortion, female infanticide, neglect and overwork of girls, dowry deaths, and discrimination against widows. The results of these practices are manifest in sex ratios that are culturally rather than naturally controlled and in demographic facts such as the calculation that 60 million females are missing in Asia alone (and perhaps more than 100 million worldwide). Women are also removed from a reproductive setting by being kidnapped or sold into prostitution or by being forced to adopt prostitution for economic survival. In cases where survival is threatened by environmental degradation and population growth, the most harsh cultural practices will emerge to adapt the population to the resources at hand. This situation creates an ethical dilemma posed by the problem of imposing Western values on a culture that is undertaking adaptive practices to insure its very survival. Ways to help women in these situation include limiting population growth humanely through family planning, provision of paid work to women, and creation of an environment that supports a small family ideal. Prosperity itself, through modernization, sometimes causes family sizes to increase. The most important intervention appears to be the provision of paid employment outside the home for women. On the other hand, large-scale wealth transfers and liberal immigration policies simply send signals that population pressure is a regional problem that can be alleviated by the international community. Increasing immigration to developed countries will place pressure on the women of those countries by increasing population. The fact that population size in the US is expected to double in 64 years already poses a threat to the status of US women who are not immune from cultural processes.

Urbanization and the problem of restricting the growth of very large cities.

PubMed

Bialkovskaia, V; Novikov, V

1983-10-01

This article discusses the problem of preventing the excessive growth of very large cities to the detriment of the development of smaller urban settlements in the USSR. The increase in size of the urban population throughout the entire USSR is mainly connected with the increase in the number of city dwellers. In 1960 and 1970 the number of largest cities in the USSR increased, along with a share of the nation's population living in these large cities. The low natural increase in population of very large cities creates a high demand for labor power which must come from the population of other cities. In 1970-1980, Moscow, one of the largest millionaire cities, had the lowest population growth rate of all major USSR cities (113.7%). The growth of Moscow and other very large cities in the last few years has been due to the mechanical increase in population and the increase in area. The analysis of Moscow's pattern of population growth over time focuses on changes in the level of availability of social and everyday services. The prewar period is characterized by a reserve of labor resources, the highest growth in industry and science, but a low overall population dynamic in the city. In the postwar period there was a significant decline in the annual increase of all indicators; this was a period of strong social development of the city. The period between 1966 and 1980 shows a further slowdown in the growth rate of city forming branches by an accelerated development of municipal service branches. The demand for measures to restrict the growth of very large Soviet cities depends on: 1) the reorientation of the development of the economic base, 2) the restructuring of their economy, and 3) the siting of various types of production of goods and services. Developing the specialization of the urban economy consists of planned development of the production of goods and services based on the use of available resources.

Using ancestry-informative markers to identify fine structure across 15 populations of European origin.

PubMed

Huckins, Laura M; Boraska, Vesna; Franklin, Christopher S; Floyd, James A B; Southam, Lorraine; Sullivan, Patrick F; Bulik, Cynthia M; Collier, David A; Tyler-Smith, Chris; Zeggini, Eleftheria; Tachmazidou, Ioanna

2014-10-01

The Wellcome Trust Case Control Consortium 3 anorexia nervosa genome-wide association scan includes 2907 cases from 15 different populations of European origin genotyped on the Illumina 670K chip. We compared methods for identifying population stratification, and suggest list of markers that may help to counter this problem. It is usual to identify population structure in such studies using only common variants with minor allele frequency (MAF) >5%; we find that this may result in highly informative SNPs being discarded, and suggest that instead all SNPs with MAF >1% may be used. We established informative axes of variation identified via principal component analysis and highlight important features of the genetic structure of diverse European-descent populations, some studied for the first time at this scale. Finally, we investigated the substructure within each of these 15 populations and identified SNPs that help capture hidden stratification. This work can provide information regarding the designing and interpretation of association results in the International Consortia.

Fitting a Structured Juvenile-Adult Model for Green Tree Frogs to Population Estimates from Capture-Mark-Recapture Field Data

USGS Publications Warehouse

Ackleh, A.S.; Carter, J.; Deng, K.; Huang, Q.; Pal, N.; Yang, X.

2012-01-01

We derive point and interval estimates for an urban population of green tree frogs (Hyla cinerea) from capture-mark-recapture field data obtained during the years 2006-2009. We present an infinite-dimensional least-squares approach which compares a mathematical population model to the statistical population estimates obtained from the field data. The model is composed of nonlinear first-order hyperbolic equations describing the dynamics of the amphibian population where individuals are divided into juveniles (tadpoles) and adults (frogs). To solve the least-squares problem, an explicit finite difference approximation is developed. Convergence results for the computed parameters are presented. Parameter estimates for the vital rates of juveniles and adults are obtained, and standard deviations for these estimates are computed. Numerical results for the model sensitivity with respect to these parameters are given. Finally, the above-mentioned parameter estimates are used to illustrate the long-time behavior of the population under investigation. ?? 2011 Society for Mathematical Biology.

Ensemble of hybrid genetic algorithm for two-dimensional phase unwrapping

NASA Astrophysics Data System (ADS)

Balakrishnan, D.; Quan, C.; Tay, C. J.

2013-06-01

The phase unwrapping is the final and trickiest step in any phase retrieval technique. Phase unwrapping by artificial intelligence methods (optimization algorithms) such as hybrid genetic algorithm, reverse simulated annealing, particle swarm optimization, minimum cost matching showed better results than conventional phase unwrapping methods. In this paper, Ensemble of hybrid genetic algorithm with parallel populations is proposed to solve the branch-cut phase unwrapping problem. In a single populated hybrid genetic algorithm, the selection, cross-over and mutation operators are applied to obtain new population in every generation. The parameters and choice of operators will affect the performance of the hybrid genetic algorithm. The ensemble of hybrid genetic algorithm will facilitate to have different parameters set and different choice of operators simultaneously. Each population will use different set of parameters and the offspring of each population will compete against the offspring of all other populations, which use different set of parameters. The effectiveness of proposed algorithm is demonstrated by phase unwrapping examples and advantages of the proposed method are discussed.

Unveiling adaptation using high-resolution lineage tracking

NASA Astrophysics Data System (ADS)

Blundell, Jamie; Levy, Sasha; Fisher, Daniel; Petrov, Dmitri; Sherlock, Gavin

2013-03-01

Human diseases such as cancer and microbial infections are adaptive processes inside the human body with enormous population sizes: between 106 -1012 cells. In spite of this our understanding of adaptation in large populations is limited. The key problem is the difficulty in identifying anything more than a handful of rare, large-effect beneficial mutations. The development and use of molecular barcodes allows us to uniquely tag hundreds of thousands of cells and enable us to track tens of thousands of adaptive mutations in large yeast populations. We use this system to test some of the key theories on which our understanding of adaptation in large populations is based. We (i) measure the fitness distribution in an evolving population at different times, (ii) identify when an appreciable fraction of clones in the population have at most a single adaptive mutation and isolate a large number of clones with independent single adaptive mutations, and (iii) use this clone collection to determine the distribution of fitness effects of single beneficial mutations.

Hydrological problems of water resources in irrigated agriculture: A management perspective

NASA Astrophysics Data System (ADS)

Singh, Ajay

2016-10-01

The development of irrigated agriculture is necessary for fulfilling the rising food requirements of the burgeoning global population. However, the intensification of irrigated agriculture causes the twin menace of waterlogging and soil salinization in arid and semiarid regions where more than 75% of the world's population lives. These problems can be managed by either adopting preventive measures which decrease the inflow of water and salt or by employing remedial measures which increase the outflow. This paper presents an overview of various measures used for the management of waterlogging and salinity problems. The background, processes involved, and severity of waterlogging and salinity problems are provided. The role of drainage systems, conjunctive use of different water sources, use of computer-based mathematical models, and the use of remote sensing and GIS techniques in managing the problems are discussed. Conclusions are provided which could be useful for all the stakeholders.

Nutrition Problem Classification for Children and Youth.

ERIC Educational Resources Information Center

Health Services Administration (DHEW/PHS), Rockville, MD. Bureau of Community Health Services.

This nutrition problem classification system is an attempt to classify the nutritional needs and problems of children and youth. Its two most important uses are problem identification and monitoring for individual patients and creation of an information base for developing program plans for intervention in a service population. The classification…

Cyclic public goods games: Compensated coexistence among mutual cheaters stabilized by optimized penalty taxation

NASA Astrophysics Data System (ADS)

Griffin, Christopher; Belmonte, Andrew

2017-05-01

We study the problem of stabilized coexistence in a three-species public goods game in which each species simultaneously contributes to one public good while freeloading off another public good ("cheating"). The proportional population growth is governed by an appropriately modified replicator equation, depending on the returns from the public goods and the cost. We show that the replicator dynamic has at most one interior unstable fixed point and that the population becomes dominated by a single species. We then show that by applying an externally imposed penalty, or "tax" on success can stabilize the interior fixed point, allowing for the symbiotic coexistence of all species. We show that the interior fixed point is the point of globally minimal total population growth in both the taxed and untaxed cases. We then formulate an optimal taxation problem and show that it admits a quasilinearization, resulting in novel necessary conditions for the optimal control. In particular, the optimal control problem governing the tax rate must solve a certain second-order ordinary differential equation.

Hierarchical modeling and inference in ecology: The analysis of data from populations, metapopulations and communities

USGS Publications Warehouse

Royle, J. Andrew; Dorazio, Robert M.

2008-01-01

A guide to data collection, modeling and inference strategies for biological survey data using Bayesian and classical statistical methods. This book describes a general and flexible framework for modeling and inference in ecological systems based on hierarchical models, with a strict focus on the use of probability models and parametric inference. Hierarchical models represent a paradigm shift in the application of statistics to ecological inference problems because they combine explicit models of ecological system structure or dynamics with models of how ecological systems are observed. The principles of hierarchical modeling are developed and applied to problems in population, metapopulation, community, and metacommunity systems. The book provides the first synthetic treatment of many recent methodological advances in ecological modeling and unifies disparate methods and procedures. The authors apply principles of hierarchical modeling to ecological problems, including * occurrence or occupancy models for estimating species distribution * abundance models based on many sampling protocols, including distance sampling * capture-recapture models with individual effects * spatial capture-recapture models based on camera trapping and related methods * population and metapopulation dynamic models * models of biodiversity, community structure and dynamics.

Orbiting space debris: Dangers, measurement and mitigation

NASA Astrophysics Data System (ADS)

McNutt, Ross T.

1992-06-01

Space debris is a growing environmental problem. Accumulation of objects in earth orbit threatens space systems through the possibility of collisions and runaway debris multiplication. The amount of debris in orbit is uncertain due to the lack of information on the population of debris between 1 and 10 centimeters diameter. Collisions with debris even smaller than 1 cm can be catastrophic due to the high orbital velocities involved. Research efforts are under way at NASA, United States Space Command and the Air Force Phillips Laboratory to detect and catalog the debris population in near-earth space. Current international and national laws are inadequate to control the proliferation of space debris. Space debris is a serious problem with large economic, military, technical and diplomatic components. Actions need to be taken now to: determine the full extent of the orbital debris problem; accurately predict the future evolution of the debris population; decide the extent of the debris mitigation procedures required; implement these policies on a global basis via an international treaty. Action must be initiated now, before the loss of critical space systems such as the space shuttle or the space station.

Cyclic public goods games: Compensated coexistence among mutual cheaters stabilized by optimized penalty taxation.

PubMed

Griffin, Christopher; Belmonte, Andrew

2017-05-01

We study the problem of stabilized coexistence in a three-species public goods game in which each species simultaneously contributes to one public good while freeloading off another public good ("cheating"). The proportional population growth is governed by an appropriately modified replicator equation, depending on the returns from the public goods and the cost. We show that the replicator dynamic has at most one interior unstable fixed point and that the population becomes dominated by a single species. We then show that by applying an externally imposed penalty, or "tax" on success can stabilize the interior fixed point, allowing for the symbiotic coexistence of all species. We show that the interior fixed point is the point of globally minimal total population growth in both the taxed and untaxed cases. We then formulate an optimal taxation problem and show that it admits a quasilinearization, resulting in novel necessary conditions for the optimal control. In particular, the optimal control problem governing the tax rate must solve a certain second-order ordinary differential equation.

Fertility decline and population growth: China's dilemma.

PubMed

Gu, B

1996-02-01

This article includes the assertion by the deputy director and demographer of the China Information and Research Center that China must maintain and implement a strict population policy in order to feed its large population. China has 22% of the world's total population but only 7% of the world's total cultivated land. The population rate varies by province and region in China and ranges from replacement level fertility in Shanghai to high growth in remote and underdeveloped provinces. About 70 million people live under the poverty line or have an annual family income of under 500 yuan. The family planning programs should emphasize a service oriented approach. The increased power of women and improved educational status of women are also desired. Concern is recognized in government circles about the rapid aging of the population. Rural-urban migration has improved the economic climate in cities, but migration has also resulted in "some serious social problems." China has a low fertility level but rapid population growth. In the 1990s about 21 million babies were born, which is a net increase of about 14 million annually. Population growth is serious because of a strong population momentum from the previous baby boom of the 1960s. China has accomplished a great deal in a short period of time in reducing fertility under unfavorable socioeconomic conditions. Credit must be given to the Chinese government, its various departments, and public response. Present population is over 1.2 billion, which is higher than the total population of developed countries of the world.

Use of genetic data to infer population-specific ecological and phenotypic traits from mixed aggregations

USGS Publications Warehouse

Moran, Paul; Bromaghin, Jeffrey F.; Masuda, Michele

2014-01-01

Many applications in ecological genetics involve sampling individuals from a mixture of multiple biological populations and subsequently associating those individuals with the populations from which they arose. Analytical methods that assign individuals to their putative population of origin have utility in both basic and applied research, providing information about population-specific life history and habitat use, ecotoxins, pathogen and parasite loads, and many other non-genetic ecological, or phenotypic traits. Although the question is initially directed at the origin of individuals, in most cases the ultimate desire is to investigate the distribution of some trait among populations. Current practice is to assign individuals to a population of origin and study properties of the trait among individuals within population strata as if they constituted independent samples. It seemed that approach might bias population-specific trait inference. In this study we made trait inferences directly through modeling, bypassing individual assignment. We extended a Bayesian model for population mixture analysis to incorporate parameters for the phenotypic trait and compared its performance to that of individual assignment with a minimum probability threshold for assignment. The Bayesian mixture model outperformed individual assignment under some trait inference conditions. However, by discarding individuals whose origins are most uncertain, the individual assignment method provided a less complex analytical technique whose performance may be adequate for some common trait inference problems. Our results provide specific guidance for method selection under various genetic relationships among populations with different trait distributions.

Use of Genetic Data to Infer Population-Specific Ecological and Phenotypic Traits from Mixed Aggregations

PubMed Central

Moran, Paul; Bromaghin, Jeffrey F.; Masuda, Michele

2014-01-01

Many applications in ecological genetics involve sampling individuals from a mixture of multiple biological populations and subsequently associating those individuals with the populations from which they arose. Analytical methods that assign individuals to their putative population of origin have utility in both basic and applied research, providing information about population-specific life history and habitat use, ecotoxins, pathogen and parasite loads, and many other non-genetic ecological, or phenotypic traits. Although the question is initially directed at the origin of individuals, in most cases the ultimate desire is to investigate the distribution of some trait among populations. Current practice is to assign individuals to a population of origin and study properties of the trait among individuals within population strata as if they constituted independent samples. It seemed that approach might bias population-specific trait inference. In this study we made trait inferences directly through modeling, bypassing individual assignment. We extended a Bayesian model for population mixture analysis to incorporate parameters for the phenotypic trait and compared its performance to that of individual assignment with a minimum probability threshold for assignment. The Bayesian mixture model outperformed individual assignment under some trait inference conditions. However, by discarding individuals whose origins are most uncertain, the individual assignment method provided a less complex analytical technique whose performance may be adequate for some common trait inference problems. Our results provide specific guidance for method selection under various genetic relationships among populations with different trait distributions. PMID:24905464

Recruiting Gamblers from the General Population for Research Purposes: Outcomes from Two Contrasting Approaches

ERIC Educational Resources Information Center

Williams, Jeremy D.; Pulford, Justin; Bellringer, Maria; Abbott, Max

2010-01-01

Multiple means exist by which gamblers including problem gamblers may be recruited from the general population for research survey purposes. However, there appears to be limited discussion in the published literature about the relative merits of one or other approach. This paper addresses this gap, in part, by reporting the experiences of…

Chronic Physical Illness and Mental Health in Children. Results from a Large-Scale Population Study

ERIC Educational Resources Information Center

Hysing, Mari; Elgen, Irene; Gillberg, Christopher; Lie, Stein Atle; Lundervold, Astri J.

2007-01-01

Background: The aim of the present study was to evaluate the sensitivity and specificity of the Strengths and Difficulties Questionnaire (SDQ) in detecting emotional and behavioural problems among children with chronic illness (CI). Methods: Parents and teachers of a population of primary school children in Norway (n = 9430) completed a…

Using the University Student Depression Inventory to Investigate the Effect of Demographic Variables on Students' Depression

ERIC Educational Resources Information Center

Khawaja, Nigar G.; Duncanson, Krystle

2008-01-01

Depression is a problem in the student population and may impact students of any age, gender and ethnicity. Previous studies have indicated student demographic characteristics are associated with depression; however, these studies have not utilised scales specifically designed to measure depression in the student population. The aim of the present…

Thinking Globally, Acting Locally About Food, Population and Energy Issues. Seventh Grade Interdisciplinary Unit.

ERIC Educational Resources Information Center

Miller, Barbara, Ed.

This social studies unit suggests activities and teaching methods for use by seventh grade social studies classroom teachers as they develop and implement educational programs on global food, population, and energy problems. Objectives are to help students become aware of global interdependence, identify roles of various nations in causing and…

Issues Concerning Self-Report Data and Population-Based Data Sets Involving People with Intellectual Disabilities

ERIC Educational Resources Information Center

Emerson, Eric; Felce, David; Stancliffe, Roger J.

2013-01-01

This article examines two methodological issues regarding ways of obtaining and analyzing outcome data for people with intellectual disabilities: (a) self-report and proxy-report data and (b) analysis of population-based data sets. Some people with intellectual disabilities have difficulties with self-reporting due to problems of understanding and…

Cost Effectiveness of Individual versus Group Cognitive Behavior Therapy for Problems of Depression and Anxiety in an HMO Population.

ERIC Educational Resources Information Center

Shapiro, Joan; And Others

1982-01-01

Compared the cost effectiveness of cognitive behavior group therapy, traditional process-oriented interpersonal group, and individual cognitive behavior therapy in dealing with depression and anxiety in a health maintenance organization population (N=44). Results suggest that cost considerations can become relatively important when decisions are…

Primary Distance Education Population: Problems and Prospects. Research Series No. 2.

ERIC Educational Resources Information Center

Taylor, Peter; Tomlinson, Derrick

Extensive fieldwork and a questionnaire were used to study the population served by primary distance education (k-6), the perceived needs of home tutors, and the adequacy of support services provided by distance primary schools in New South Wales, Queensland, Western Australia, and the Northern Territory. The fieldwork phase found two major types…

Training the Nation's Health Manpower.

ERIC Educational Resources Information Center

National Institutes of Health (DHEW), Bethesda, MD. Bureau of Health Manpower Education.

Over the past decade, there has been an increasing concern about the lack of health manpower to serve the U.S. population. The areas hardest hit by this shortage are the poverty areas in large cities and rural areas where 30% of the population but only 10% of the physicians live. Many Federal programs have begun to alleviate the problem of the…

Greece's high dentist to population ratio: comparisons, causes, and effects.

PubMed

Koletsi-Kounari, Haroula; Papaioannou, William; Stefaniotis, Theodoros

2011-11-01

Reaching the optimal dentist to population ratio is a common health policy challenge around the world, but while many countries have too few dentists for their populations, Greece is facing the opposite problem. This study was designed to describe and analyze trends in the number and distribution of dentists in Greece over the last thirty years and compare the Greek dentist to population ratio with that of the other twenty-six European Union (EU) countries. Demographic data for Greece were obtained from the Hellenic Dental Association and the National Statistical Service of Greece and were analyzed using nonparametric statistical tests. Data for the other EU countries were derived from various authoritative sources. In Greece, the number of dentists per 10,000 inhabitants increased significantly (p<0.05) from 1982 (7.7) to 2007 (13.0), ranking Greece first (in 2008) among the EU countries. The proportional increase in the number of dentists during the decade 1979-88 (30.4 percent) was significant (p<0.05), compared to the decade 1989-98 (22.3 percent) and the nine-year period 1999-2007 (23.6 percent). In 1982 and 1992, the majority of dentists practiced in the Attica Prefecture (Athens) (55.2 percent and 52.6 percent, respectively), but this situation changed significantly in 2007 (p<0.05) (40.1 percent for Attica). The percentage of female dentists remained almost the same from 1982 until 2007, but female dentists' location of practice changed significantly (p<0.05) between 1992 and 2007. After reporting the data, we examine some of the reasons for and effects of the situation and consider the problem that, even with a high dentist to population ratio, Greece has significant oral health access problems.

Motivation and Adult Education

ERIC Educational Resources Information Center

Veeraraghavan, J.

1974-01-01

The paper examines the role of adult education and the contribution it can make to the solution of current problems in developing countries, particularly the problems of economic under-development and over-population. (Author/AG)

Reducing the Impact of Attacks against Healthcare by Curbing the Use of Explosive Weapons in Populated Areas: Developments at the Global Level.

PubMed

Bagshaw, Simon

Attacks against healthcare in situations of armed conflict have emerged as an issue of increasing concern with explosive weapons - such as aircraft bombs, mortars and improvised explosive devices - accounting for more deaths, injuries and damage than any other type of weapon in attacks on healthcare facilities. While this is perhaps unsurprising, it offers some insight into a possible course of action for dealing with the problem of attacks against healthcare - by curbing the use of explosive weapons in populated areas. There has been growing recognition in recent years of the humanitarian problems caused by the use of such weapons in populated areas. Steps are now being taken at the global level to curb this use which could, in time, make an important contribution to reducing the incidence and devastating impact of attacks against healthcare.

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

Diwan, R.

India is generally known as a poor, overpopulated, and underdeveloped country. Its per capita income, even in 1976-77, is less than 100 U.S. dollars. In the 1971 census India's population was estimated at 550 million, or approximately 15% of the world population. It is projected that the 1976 Indian population is close to 600 million. Its government has been making major efforts attacking the problem of underdevelopment; in these efforts it is assumed that once the country is developed, the twin problems of poverty and overpopulation also will be solved. To remove underdevelopment, India has instituted the mechanism of five-yearmore » plans which are an attempt in generating a development process. In this paper the energy implications of this development process are analyzed during the last decade of 1960-1970. Even though changes have taken place in the years 1970-1976, they are not fundamentally or structurally different from the trends established in the ten-year span under study.« less

Doping in sports and its spread to at-risk populations: an international review

PubMed Central

BARON, DAVID A; MARTIN, DAVID M; ABOL MAGD, SAMIR

2007-01-01

Doping is now a global problem that follows international sporting events worldwide. International sports federations, led by the International Olympic Committee, have for the past half century attempted to stop the spread of this problem, with little effect. It was expected that, with educational programs, testing, and supportive medical treatment, this substance-abusing behavior would decrease. Unfortunately, this has not been the case. In fact, new, more powerful and undetectable doping techniques and substances are now abused by professional athletes, while sophisticated networks of distribution have developed. Professional athletes are often the role models of adolescent and young adult populations, who often mimic their behaviors, including the abuse of drugs. This review of doping within international sports is to inform the international psychiatric community and addiction treatment professionals of the historical basis of doping in sport and its spread to vulnerable athletic and non-athletic populations. PMID:18235871

An intelligent case-adjustment algorithm for the automated design of population-based quality auditing protocols.

PubMed

Advani, Aneel; Jones, Neil; Shahar, Yuval; Goldstein, Mary K; Musen, Mark A

2004-01-01

We develop a method and algorithm for deciding the optimal approach to creating quality-auditing protocols for guideline-based clinical performance measures. An important element of the audit protocol design problem is deciding which guide-line elements to audit. Specifically, the problem is how and when to aggregate individual patient case-specific guideline elements into population-based quality measures. The key statistical issue involved is the trade-off between increased reliability with more general population-based quality measures versus increased validity from individually case-adjusted but more restricted measures done at a greater audit cost. Our intelligent algorithm for auditing protocol design is based on hierarchically modeling incrementally case-adjusted quality constraints. We select quality constraints to measure using an optimization criterion based on statistical generalizability coefficients. We present results of the approach from a deployed decision support system for a hypertension guideline.

The West Indian manatee (Trichechus manatus) in Florida: a summary and analysis of biological, ecological, and administrative problems affecting preservation and restoration of the population. Final report

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

Wray, P.

1978-09-01

The population of the West Indian manatee (Trichechus manatus), an endangered species, is estimated at 800-1,000 individuals in peninsular Florida. Observed annual mortality between 1974 and 1977 was 6-8% of the estimated population. Human activities are implicated in much of this mortality. Direct and indirect threats include boat collisions, diver harassment, creation of artificial warm water refuges, vandalism, entanglement in fishing gear, herbicides in food resources, and possible effects of offshore oil exploration. Lack of federal commitment to manatee protection is evidenced by an absence of implementing regulations under the Marine Mammal Protection Act and the Endangered Species Act, absencemore » of a recovery plan for the species, faulty interagency communication, and a lack of law enforcement. Problems are discussed, with recommendations for conservation. (Color illustrations reproduced in black and white)« less

[Population pressure: a factor of political destabilization].

PubMed

Tallon, F

1993-04-01

Political stability throughout the world appears to be greater in countries with slowly growing populations than in those with rapid growth. Population is not the only influence on political stability, however. The relationship between political stability and development is strong. The rich countries with the slowest growth are the most stable, while poor developing countries with rapid growth suffer from chronic instability. Demographic pressure and density are not the same thing and must be distinguished. A fragile environment like that of the Sahel will experience demographic pressure despite low density. Japan has a greater population density than Rwanda and little cultivable land, but the population has a high standard of living. demographic pressure is not comparable in Japan and Rwanda because Japan has slow population growth and stable democratic political institutions. The rate of growth seems to be a more important element in destabilization than density. Rapid growth creates enormous political tensions especially when profound ethnic divisions exist, and it complicates problems of government by encouraging rapid urbanization. The unbalanced age structures resulting from rapid growth hinder the satisfaction of employment, educational, and health care needs for the ever-increasing masses of young people. 49% of Rwanda's population is under 15 and 66% is under 25. Rwanda is already densely populated, with around 300 inhabitants/sq km, and its population is projected to double in 20 years. 95% of the population is dependent on agriculture, but by 1988 the average landholding per family was only 1.25 hectares and 58% of families did not grown sufficient food for household needs. Further reduction in the size of holdings or a growing landless population will have multiple consequences. Urban migration will inevitably increase, bringing with it all the problems so evident in other poor countries where the process is more advanced than in Rwanda. Chaotic urbanization is in itself a destabilizing force. The phenomenon of potential political destabilization due to demographic pressure had been analyzed according to different criteria. Unconstitutional sudden changes of government, incomplete civil and political liberties, violent conflicts between ethnic and other subgroups, and the frustrated aspirations of large numbers of young persons are among possible indicators of political instability. A report by the Population Crisis committee which evaluated these indicators in different countries placed Rwanda 39th among 120 countries for potential destabilization. But the period of observation avoided the 1973 disturbances and the 1990 war in Rwanda. The results would undoubtedly be considerably less favorable if the period of observation extended to the present.

Sexual problems in people with refractory epilepsy.

PubMed

Henning, Oliver J; Nakken, Karl O; Træen, Bente; Mowinckel, Petter; Lossius, Morten

2016-08-01

Sexual dysfunction is an important but often neglected aspect of epilepsy. The objective of this study was to explore the prevalence and types of sexual problems in patients with epilepsy and compare the results with similar data obtained from a representative sample of the general population. At the National Centre for Epilepsy in Norway, 171 of 227 consecutive adult inpatients and outpatients with epilepsy (response rate: 75.3%) and their neurologists participated in a questionnaire study about epilepsy and sexuality. The results were compared with data available from 594 adult Norwegians who had completed the same questionnaire. Patients with epilepsy had a significantly higher prevalence of sexual problems (women: 75.3% vs. 12.0%; men: 63.3% vs. 9.6%). The most commonly reported problems (>30%) were reduced sexual desire, orgasm problems, erection problems, and vaginal dryness. The patients reported considerable dissatisfaction regarding sexual functioning. Significantly more sexual problems were found in patients of both sexes with reduced quality of life and in women with symptoms of depression. We found no significant association between sexual problems and age of epilepsy onset, type of epilepsy, or use of enzyme-inducing antiepileptic drugs. Whereas age at sexual debut did not differ between the patients with epilepsy and the general population, men with epilepsy had a lower number of partners during the last 12months, and the proportion of women with a low frequency of intercourse was higher in the group with epilepsy. In conclusion, sexual problems are significantly greater in Norwegian patients with epilepsy than in the general adult population. As no single epilepsy type or treatment could be identified as a specific predisposing factor, it seems likely that there are multiple causes underlying our results, including both organic and psychosocial factors. Copyright © 2016 Elsevier Inc. All rights reserved.

Ethical issues of global corporatization: agriculture and beyond.

PubMed

Pimentel, D

2004-03-01

The world food supply has become inadequate for more than half the world population, as evidenced by a recent report of the World Health Organization that indicated that more than 3 billion people are malnourished. This is the largest number of malnourished ever reported. Per capita food production, especially cereal grains, has been declining for nearly 2 decades, despite new biotechnology and other agricultural technologies. Rapid human population growth, compounded by diminishing availability of fertile cropland, freshwater, and fossil fuels, is intensifying the emerging problems in all food production systems. Numerous ethical issues are related to the problem of malnutrition, including global corporatization.

Problems with the claim of ecotype and taxon status of the wolf in the Great Lakes region

USGS Publications Warehouse

Cronin, Matthew A.; Mech, L. David

2009-01-01

Koblmuller et al. (2009) analysed molecular genetic data of the wolf in the Great Lakes (GL) region of the USA and concluded that the animal was a unique ecotype of grey wolf and that genetic data supported the population as a discrete wolf taxon. However, some of the literature that the researchers used to support their position actually did not, and additional confusion arises from indefinite use of terminology. Herein, we discuss the problems with designation of a wolf population as a taxon or ecotype without proper definition and assessment of criteria.

Efforts to support special-needs soldiers serving in the Israeli defense forces.

PubMed

Bodner, Ehud; Iancu, Iulian; Sarel, Amiram; Einat, Haim

2007-11-01

Providing treatment and support to special-needs populations can decrease psychopathology and suicide rates. Because service in the military is an important socializing force in Israeli society and most Israelis serve, the Israeli Defense Forces (IDF) makes special efforts to identify, treat, and support soldiers with emotional, behavioral, and cognitive problems. This column describes the IDF's efforts for three groups of soldiers with special needs, with a focus on those with the most severe problems who receive support throughout their service to address psychopathology and suicidality. Suicide rates for the IDF population and for the three groups are reported.

Game On: Past Year Gambling, Gambling-Related Problems, and Fantasy Sports Gambling Among College Athletes and Non-athletes.

PubMed

Martin, Ryan J; Nelson, Sarah E; Gallucci, Andrew R

2016-06-01

College students experience higher rates of gambling-related problems than most other population segments, including the general population. Although Division I (D1) athletes often have more at stake than the average student if and when they gamble (e.g., the potential to lose their athletic eligibility), relatively few studies have assessed the gambling behavior of this population and none have specifically assessed fantasy sports gambling. We conducted a study to examine gambling behavior (past-year gambling, gambling-related problems, and fantasy sport gambling) among a sample (N = 692) of college students at a private religiously affiliated university in the Southwest US. The sample for our study was unique in that approximately 30 % of the participants were D1 athletes. We compared the gambling behavior among three groups based on the athlete status: D1 athletes, club/intramural/recreational (CIR) athletes, and non-athletes (NAs). Compared to females in our sample, males observed higher rates of past year gambling, fantasy sports participation, fantasy sports gambling, and gambling-related problems. Among males, we found that CIR athletes observed the highest rates of past year gambling and fantasy sports participation and D1 athletes observed higher rates than NAs. We did not find differences in fantasy sport gambling and past year gambling-related problems based on athlete status in males or females.

Helping the healer: population-informed workplace wellness recommendations for physician well-being.

PubMed

Brooks, E; Early, S R; Gendel, M H; Miller, L; Gundersen, D C

2018-05-23

The need to keep physicians healthy and in practice is critical as demand for doctors grows faster than the supply. Workplace wellness programmes can improve employee health and retain skilled workers. To broaden our understanding about ways to help doctors coping with mental health problems and to develop population-informed workplace wellness recommendations for physician populations. Researchers surveyed physicians to document potential warning signs and prevention strategies. A survey was issued to doctors who presented to a physician health programme with mental health complaints. The survey captured respondents' feedback about how to identify and prevent mental health problems. Data were analyzed using simple descriptive statistics. There were 185 participants. Half of respondents believed their problems could have been recognized sooner and 60% said they exhibited signs that could aid in earlier detection. Potential warnings included fluctuations in mood (67%), increased comments about stress/burnout (49%) and behavioural changes (32%). To improve detection, prevention and care-seeking for mental health problems, doctors endorsed multiple items related to the use of interpersonal supports, personal factors and organizational dynamics throughout the survey. The findings confirmed earlier work demonstrating the value of social and organizational support in maintaining physician health. It further indicated that earlier identification and/or prevention of mental health problems is not only possible, but that medical organizations are uniquely situated to carry out this work.

Identification of drug-resistant subpopulations in canine hemangiosarcoma

PubMed Central

Khammanivong, A.; Gorden, B. H.; Frantz, A. M.; Graef, A. J.; Dickerson, E. B.

2017-01-01

Canine hemangiosarcoma is a rapidly progressive disease that is poorly responsive to conventional chemotherapy. Despite numerous attempts to advance treatment options and improve outcomes, drug resistance remains a hurdle to successful therapy. To address this problem, we used recently characterized progenitor cell populations derived from canine hemangiosarcoma cell lines and grown as non-adherent spheres to identify potential drug resistance mechanisms as well as drug-resistant cell populations. Cells from sphere-forming cultures displayed enhanced resistance to chemotherapy drugs, expansion of dye-excluding side populations and altered ATP-binding cassette (ABC) transporter expression. Invasion studies demonstrated variability between cell lines as well as between sphere and monolayer cell populations. Collectively, our results suggest that sphere cell populations contain distinct subpopulations of drug-resistant cells that utilize multiple mechanisms to evade cytotoxic drugs. Our approach represents a new tool for the study of drug resistance in hemangiosarcoma, which could alter approaches for treating this disease. PMID:25112808

The role of multiple stressor causes in declining amphibian populations: a wingspread workshop summary

USGS Publications Warehouse

Krest, S.K.; Linder, G.; Sparling, D.W.; Linder, Gregory L.; Krest, Sherry K.; Sparling, Donald W.; Little, Edward E.

2003-01-01

Numerous studies have documented the decline of amphibian populations over the past decade and no single factor has been the linked to these widespread declines. Determining the causes of declining amphibian populations worldwide has proven difficult because of the variety of anthropogenic and natural suspect agents. A Wingspread workshop, convened by The Society of Environmental Toxicology and Chemistry (SETAC), brought together individuals with expertise in the areas of amphibian biology, ecotoxicology, natural resource management, and environmental policy. This workshop had three objectives: 1) create a network for future discussions on multiple stressor causes of declines; 2) characterize and prioritize technical issues critical to the analysis of the decline problem; and 3) identify and develop resource management approaches to promote sustainable and healthy amphibian populations. The workshop proceedings will be summarized in a book entitled, 'Multiple Stressors and Declining Amphibian Populations: Evaluating Cause and Effect.' This paper summarizes the results of the workshop.

The role of multiple stressor causes in declining amphibian populations: A wingspread workshop summary

USGS Publications Warehouse

Krest, S.K.; Linder, G.; Sparling, D.W.; ,

2003-01-01

Numerous studies have documented the decline of amphibian populations over the past decade and no single factor has been the linked to these widespread declines. Determining the causes of declining amphibian populations worldwide has proven difficult because of the variety of anthropogenic and natural suspect agents. A Wingspread workshop, convened by The Society of Environmental Toxicology and Chemistry (SETAC), brought together individuals with expertise in the areas of amphibian biology, ecotoxicology, natural resource management, and environmental policy. This workshop had three objectives: 1) create a network for future discussions on multiple Stressor causes of declines; 2) characterize and prioritize technical issues critical to the analysis of the decline problem; and 3) identify and develop resource management approaches to promote sustainable and healthy amphibian populations. The workshop proceedings will be summarized in a book entitled, "Multiple Stressors and Declining Amphibian Populations: Evaluating Cause and Effect." This paper summarizes the results of the workshop.

Dasymetric high resolution population distribution estimates for improved decision making, with a case study of sea-level rise vulnerability in Boca Raton, Florida

NASA Astrophysics Data System (ADS)

Ziegler, Hannes Moritz

Planners and managers often rely on coarse population distribution data from the census for addressing various social, economic, and environmental problems. In the analysis of physical vulnerabilities to sea-level rise, census units such as blocks or block groups are coarse relative to the required decision-making application. This study explores the benefits offered from integrating image classification and dasymetric mapping at the household level to provide detailed small area population estimates at the scale of residential buildings. In a case study of Boca Raton, FL, a sea-level rise inundation grid based on mapping methods by NOAA is overlaid on the highly detailed population distribution data to identify vulnerable residences and estimate population displacement. The enhanced spatial detail offered through this method has the potential to better guide targeted strategies for future development, mitigation, and adaptation efforts.

Egypt: urban growth encroaches on farmland.

PubMed

1981-12-01

In 1980 Egypt's population was 42 million, with 9 million, or 21%, residing in metropolitan Cairo. Throughout the country the urban population makes up about 44% of the total population; in the 2 largest cities, Cairo and Alexandria, public utilities and basic services are becoming more and more ineffective. The problem is complicated by the fact that the urban population is concentrated along the Nile valley, which is the most fertile, cultivated, and well watered area of the country. An estimated 20,000 acres of farmland are lost each year to urban spread, while the government spends an average $2 million yearly to subsidize food imports. The Egyptian government is not only aiming at reducing natural growth through the provision of free family planning services, but it is encouraging rural development and trying to raise the standard of living for farmers. A strategy to redistribute the population into smaller cities or on land suitable for reclamation is also being planned.

Extinction dynamics of a discrete population in an oasis.

PubMed

Berti, Stefano; Cencini, Massimo; Vergni, Davide; Vulpiani, Angelo

2015-07-01

Understanding the conditions ensuring the persistence of a population is an issue of primary importance in population biology. The first theoretical approach to the problem dates back to the 1950s with the Kierstead, Slobodkin, and Skellam (KiSS) model, namely a continuous reaction-diffusion equation for a population growing on a patch of finite size L surrounded by a deadly environment with infinite mortality, i.e., an oasis in a desert. The main outcome of the model is that only patches above a critical size allow for population persistence. Here we introduce an individual-based analog of the KiSS model to investigate the effects of discreteness and demographic stochasticity. In particular, we study the average time to extinction both above and below the critical patch size of the continuous model and investigate the quasistationary distribution of the number of individuals for patch sizes above the critical threshold.

Homogenization techniques for population dynamics in strongly heterogeneous landscapes.

PubMed

Yurk, Brian P; Cobbold, Christina A

2018-12-01

An important problem in spatial ecology is to understand how population-scale patterns emerge from individual-level birth, death, and movement processes. These processes, which depend on local landscape characteristics, vary spatially and may exhibit sharp transitions through behavioural responses to habitat edges, leading to discontinuous population densities. Such systems can be modelled using reaction-diffusion equations with interface conditions that capture local behaviour at patch boundaries. In this work we develop a novel homogenization technique to approximate the large-scale dynamics of the system. We illustrate our approach, which also generalizes to multiple species, with an example of logistic growth within a periodic environment. We find that population persistence and the large-scale population carrying capacity is influenced by patch residence times that depend on patch preference, as well as movement rates in adjacent patches. The forms of the homogenized coefficients yield key theoretical insights into how large-scale dynamics arise from the small-scale features.

Poverty-led higher population growth in Bangladesh.

PubMed

Nakibullah, A; Rahman, A

1996-01-01

This article discusses the issue whether population growth is exogenous or endogenous in the economic development of Bangladesh. Overpopulation adversely affects food supplies, foreign exchange, and human resources. Moreover, it depresses savings per capita and retards growth of physical capital per labor. Underdeveloped countries, like Bangladesh, are faced with the problem of allocating resources between infrastructure, education, and health service that are essential for human capital development and population control measures. With this, determination whether fertility is exogenous or endogenous is important for policy purposes in the context of Bangladesh. Results showed that there is a correlation between population growth and real gross domestic products per capita. Based on Granger causality test, population growth is endogenous in the development process of Bangladesh and its overpopulation is due to poverty. Thus, there is a need for appropriate policy to take measures to improve human capital and decrease fertility rates.

Connecting micro dynamics and population distributions in system dynamics models

PubMed Central

Rahmandad, Hazhir; Chen, Hsin-Jen; Xue, Hong; Wang, Youfa

2014-01-01

Researchers use system dynamics models to capture the mean behavior of groups of indistinguishable population elements (e.g., people) aggregated in stock variables. Yet, many modeling problems require capturing the heterogeneity across elements with respect to some attribute(s) (e.g., body weight). This paper presents a new method to connect the micro-level dynamics associated with elements in a population with the macro-level population distribution along an attribute of interest without the need to explicitly model every element. We apply the proposed method to model the distribution of Body Mass Index and its changes over time in a sample population of American women obtained from the U.S. National Health and Nutrition Examination Survey. Comparing the results with those obtained from an individual-based model that captures the same phenomena shows that our proposed method delivers accurate results with less computation than the individual-based model. PMID:25620842

Population size estimation in Yellowstone wolves with error-prone noninvasive microsatellite genotypes.

PubMed

Creel, Scott; Spong, Goran; Sands, Jennifer L; Rotella, Jay; Zeigle, Janet; Joe, Lawrence; Murphy, Kerry M; Smith, Douglas

2003-07-01

Determining population sizes can be difficult, but is essential for conservation. By counting distinct microsatellite genotypes, DNA from noninvasive samples (hair, faeces) allows estimation of population size. Problems arise because genotypes from noninvasive samples are error-prone, but genotyping errors can be reduced by multiple polymerase chain reaction (PCR). For faecal genotypes from wolves in Yellowstone National Park, error rates varied substantially among samples, often above the 'worst-case threshold' suggested by simulation. Consequently, a substantial proportion of multilocus genotypes held one or more errors, despite multiple PCR. These genotyping errors created several genotypes per individual and caused overestimation (up to 5.5-fold) of population size. We propose a 'matching approach' to eliminate this overestimation bias.

A Mathematical Model for Alternation of Polygamy and Parthenogenesis: Stability Versus Efficiency and Analogy with Parasitism.

PubMed

Sanchez-Palencia, Evariste; Lherminier, Philippe; Françoise, Jean-Pierre

2016-12-01

The present work is a contribution to the understanding of the sempiternal problem of the "burden of factor two" implied by sexual reproduction versus asexual one, as males are energy consumers not contributing to the production of offspring. We construct a deterministic mathematical model in population dynamics where a species enjoys both sexual and parthenogenetic capabilities of reproduction and lives on a limited resource. We then show how polygamy implies instability of a parthenogenetic population with a small number of sexually born males. This instability implies evolution of the system towards an attractor involving both (sexual and asexual) populations (which does not imply optimality of the population). We also exhibit the analogy with a parasite/host system.