Epidemiology of human leukocyte antigens among omani population.

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Al Salmi, Issa; Metry, Abdul Massiah; Al Ismaili, Faisal; Hola, Alan; Shaheen, Faissal; Fakhoury, Hana; Hannawi, Suad

2017-01-01

Oman is located on the Southeastern coast of the Arabian Peninsula, and its population has high levels of consanguinity. Human leukocytic antigen (HLA) typing analysis in human population holds unexploited potential for elucidating the genetic causes of human disease and possibly leads to personalized medicine. This is a retrospective, descriptive study evaluating HLA frequencies of Omani individuals who underwent workup for kidney transplantation at the Royal Hospital (RH) from 2005 to 2016. Data on 870 subjects were collected from the Oman kidney transplant registry at RH as well from electronic medical record system. The mean age (standard deviation) years for the cohort were 33.2 (13.0). Males constituted 56.3% (490) while females constituted 43.7% (380). Seven HLA-A alleles accounted for more than 70% of the total alleles. Of which, HLA-A2 contributed the highest frequency (24%), followed by HLA A11 (9.4%), and A32 (8.1%). Ten alleles accounted for 70% of HLA-B alleles. Of which, HLA-B51 was the most common (18.9%), followed by HLA-B-35 (13.6%), and HLA-B8 (7.9%). Seven HLA-DRB1 alleles accounted for more than 70% of the total HLA DRB1 alleles, of which HLA- DRB1*16 contributed the highest frequency (29.56%). This was followed by HLA-DRB1*03 (14.57%) and HLA-DRB1*11 (9.48%). While three alleles accounted for more than 75% of the total HLA DQB1alleles. Of which, HLA-DQB1*05 contributed the highest frequency (37.56%). This was followed by allele HLA-DQB1*02 (26.48%) and HLA-DQB1*03 (17.18%). This study showed considerable heterogeneity in both HLA Class I and Class II antigens, which reflects admixture of our population with rest of old world countries. Despite the high levels of consanguinity, this population is genetically highly heterogeneous. These findings may be useful for transplantation programs, noncommunicable diseases, epidemiology of HLA linked diseases, pharmacogenomics, and anthropology.

Epidemiology of human leukocyte antigens among omani population

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Issa Al Salmi

2017-01-01

Full Text Available Oman is located on the Southeastern coast of the Arabian Peninsula, and its population has high levels of consanguinity. Human leukocytic antigen (HLA typing analysis in human population holds unexploited potential for elucidating the genetic causes of human disease and possibly leads to personalized medicine. This is a retrospective, descriptive study evaluating HLA frequencies of Omani individuals who underwent workup for kidney transplantation at the Royal Hospital (RH from 2005 to 2016. Data on 870 subjects were collected from the Oman kidney transplant registry at RH as well from electronic medical record system. The mean age (standard deviation years for the cohort were 33.2 (13.0. Males constituted 56.3% (490 while females constituted 43.7% (380. Seven HLA-A alleles accounted for more than 70% of the total alleles. Of which, HLA-A2 contributed the highest frequency (24%, followed by HLA A11 (9.4%, and A32 (8.1%. Ten alleles accounted for 70% of HLA-B alleles. Of which, HLA-B51 was the most common (18.9%, followed by HLA-B-35 (13.6%, and HLA-B8 (7.9%. Seven HLA-DRB1 alleles accounted for more than 70% of the total HLA DRB1 alleles, of which HLA- DRB1*16 contributed the highest frequency (29.56%. This was followed by HLA-DRB1*03 (14.57% and HLA-DRB1*11 (9.48%. While three alleles accounted for more than 75% of the total HLA DQB1alleles. Of which, HLA-DQB1*05 contributed the highest frequency (37.56%. This was followed by allele HLA-DQB1*02 (26.48% and HLA-DQB1*03 (17.18%. This study showed considerable heterogeneity in both HLA Class I and Class II antigens, which reflects admixture of our population with rest of old world countries. Despite the high levels of consanguinity, this population is genetically highly heterogeneous. These findings may be useful for transplantation programs, noncommunicable diseases, epidemiology of HLA linked diseases, pharmacogenomics, and anthropology.

Professional Learning in Human Resource Management: Problematising the Teaching of Reflective Practice

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Griggs, V.; Holden, R.; Rae, J.; Lawless, A.

2015-01-01

Reflection and reflective practice are much discussed aspects of professional education. This paper conveys our efforts to problematise teaching reflective practice in human resources (HR) education. The research, on which the paper is based, engages with stakeholders involved in the professional learning and education of reflective practice in…

Different level of population differentiation among human genes.

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Wu, Dong-Dong; Zhang, Ya-Ping

2011-01-14

During the colonization of the world, after dispersal out of African, modern humans encountered changeable environments and substantial phenotypic variations that involve diverse behaviors, lifestyles and cultures, were generated among the different modern human populations. Here, we study the level of population differentiation among different populations of human genes. Intriguingly, genes involved in osteoblast development were identified as being enriched with higher FST SNPs, a result consistent with the proposed role of the skeletal system in accounting for variation among human populations. Genes involved in the development of hair follicles, where hair is produced, were also found to have higher levels of population differentiation, consistent with hair morphology being a distinctive trait among human populations. Other genes that showed higher levels of population differentiation include those involved in pigmentation, spermatid, nervous system and organ development, and some metabolic pathways, but few involved with the immune system. Disease-related genes demonstrate excessive SNPs with lower levels of population differentiation, probably due to purifying selection. Surprisingly, we find that Mendelian-disease genes appear to have a significant excessive of SNPs with high levels of population differentiation, possibly because the incidence and susceptibility of these diseases show differences among populations. As expected, microRNA regulated genes show lower levels of population differentiation due to purifying selection. Our analysis demonstrates different level of population differentiation among human populations for different gene groups.

Different level of population differentiation among human genes

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Zhang Ya-Ping

2011-01-01

Full Text Available Abstract Background During the colonization of the world, after dispersal out of African, modern humans encountered changeable environments and substantial phenotypic variations that involve diverse behaviors, lifestyles and cultures, were generated among the different modern human populations. Results Here, we study the level of population differentiation among different populations of human genes. Intriguingly, genes involved in osteoblast development were identified as being enriched with higher FST SNPs, a result consistent with the proposed role of the skeletal system in accounting for variation among human populations. Genes involved in the development of hair follicles, where hair is produced, were also found to have higher levels of population differentiation, consistent with hair morphology being a distinctive trait among human populations. Other genes that showed higher levels of population differentiation include those involved in pigmentation, spermatid, nervous system and organ development, and some metabolic pathways, but few involved with the immune system. Disease-related genes demonstrate excessive SNPs with lower levels of population differentiation, probably due to purifying selection. Surprisingly, we find that Mendelian-disease genes appear to have a significant excessive of SNPs with high levels of population differentiation, possibly because the incidence and susceptibility of these diseases show differences among populations. As expected, microRNA regulated genes show lower levels of population differentiation due to purifying selection. Conclusion Our analysis demonstrates different level of population differentiation among human populations for different gene groups.

The challenges of human population ageing

DEFF Research Database (Denmark)

Sander, Miriam; Oxlund, Bjarke; Jespersen, Astrid

2015-01-01

The 20th century saw an unprecedented increase in average human lifespan as well as a rapid decline in human fertility in many countries of the world. The accompanying worldwide change in demographics of human populations is linked to unanticipated and unprecedented economic, cultural, medical...... of Copenhagen (UCPH) and the Center for Healthy Ageing at UCPH, which took place on 20-21 June 2014 in Copenhagen, Denmark. Questions discussed here include the following: what is driving age-structural change in human populations? how can we create 'age-friendly' societies and promote 'ageing...

Human population in the biodiversity hotspots.

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Cincotta, R P; Wisnewski, J; Engelman, R

2000-04-27

Biologists have identified 25 areas, called biodiversity hotspots, that are especially rich in endemic species and particularly threatened by human activities. The human population dynamics of these areas, however, are not well quantified. Here we report estimates of key demographic variables for each hotspot, and for three extensive tropical forest areas that are less immediately threatened. We estimate that in 1995 more than 1.1 billion people, nearly 20% of world population, were living within the hotspots, an area covering about 12% of Earth's terrestrial surface. We estimate that the population growth rate in the hotspots (1995-2000) is 1.8% yr(-1), substantially higher than the population growth rate of the world as a whole (1.3% yr(-1)) and above that of the developing countries (1.6% yr(-1)). These results suggest that substantial human-induced environmental changes are likely to continue in the hotspots and that demographic change remains an important factor in global biodiversity conservation. The results also underline the potential conservation significance of the continuing worldwide declines in human fertility and of policies and programs that influence human migration.

A library based fitting method for visual reflectance spectroscopy of human skin

International Nuclear Information System (INIS)

Verkruysse, Wim; Zhang Rong; Choi, Bernard; Lucassen, Gerald; Svaasand, Lars O; Nelson, J Stuart

2005-01-01

The diffuse reflectance spectrum of human skin in the visible region (400-800 nm) contains information on the concentrations of chromophores such as melanin and haemoglobin. This information may be extracted by fitting the reflectance spectrum with an optical diffusion based analytical expression applied to a layered skin model. With the use of the analytical expression, it is assumed that light transport is dominated by scattering. For port wine stain (PWS) and highly pigmented human skin, however, this assumption may not be valid resulting in a potentially large error in visual reflectance spectroscopy (VRS). Monte Carlo based techniques can overcome this problem but are currently too computationally intensive to be combined with previously used fitting procedures. The fitting procedure presented herein is based on a library search which enables the use of accurate reflectance spectra based on forward Monte Carlo simulations or diffusion theory. This allows for accurate VRS to characterize chromophore concentrations in PWS and highly pigmented human skin. The method is demonstrated using both simulated and measured reflectance spectra. An additional advantage of the method is that the fitting procedure is very fast

A library based fitting method for visual reflectance spectroscopy of human skin

Energy Technology Data Exchange (ETDEWEB)

Verkruysse, Wim [Beckman Laser Institute, University of California, Irvine, CA 92612 (United States); Zhang Rong [Beckman Laser Institute, University of California, Irvine, CA 92612 (United States); Choi, Bernard [Beckman Laser Institute, University of California, Irvine, CA 92612 (United States); Lucassen, Gerald [Personal Care Institute, Philips Research, Prof Holstlaan 4, Eindhoven (Netherlands); Svaasand, Lars O [Department of Physical Electronics Norwegian University of Science and Technology, N-7491 Trondheim (Norway); Nelson, J Stuart [Beckman Laser Institute, University of California, Irvine, CA 92612 (United States)

2005-01-07

The diffuse reflectance spectrum of human skin in the visible region (400-800 nm) contains information on the concentrations of chromophores such as melanin and haemoglobin. This information may be extracted by fitting the reflectance spectrum with an optical diffusion based analytical expression applied to a layered skin model. With the use of the analytical expression, it is assumed that light transport is dominated by scattering. For port wine stain (PWS) and highly pigmented human skin, however, this assumption may not be valid resulting in a potentially large error in visual reflectance spectroscopy (VRS). Monte Carlo based techniques can overcome this problem but are currently too computationally intensive to be combined with previously used fitting procedures. The fitting procedure presented herein is based on a library search which enables the use of accurate reflectance spectra based on forward Monte Carlo simulations or diffusion theory. This allows for accurate VRS to characterize chromophore concentrations in PWS and highly pigmented human skin. The method is demonstrated using both simulated and measured reflectance spectra. An additional advantage of the method is that the fitting procedure is very fast.

A library based fitting method for visual reflectance spectroscopy of human skin

Science.gov (United States)

Verkruysse, Wim; Zhang, Rong; Choi, Bernard; Lucassen, Gerald; Svaasand, Lars O.; Nelson, J. Stuart

2005-01-01

The diffuse reflectance spectrum of human skin in the visible region (400-800 nm) contains information on the concentrations of chromophores such as melanin and haemoglobin. This information may be extracted by fitting the reflectance spectrum with an optical diffusion based analytical expression applied to a layered skin model. With the use of the analytical expression, it is assumed that light transport is dominated by scattering. For port wine stain (PWS) and highly pigmented human skin, however, this assumption may not be valid resulting in a potentially large error in visual reflectance spectroscopy (VRS). Monte Carlo based techniques can overcome this problem but are currently too computationally intensive to be combined with previously used fitting procedures. The fitting procedure presented herein is based on a library search which enables the use of accurate reflectance spectra based on forward Monte Carlo simulations or diffusion theory. This allows for accurate VRS to characterize chromophore concentrations in PWS and highly pigmented human skin. The method is demonstrated using both simulated and measured reflectance spectra. An additional advantage of the method is that the fitting procedure is very fast.

DNA variation of the mammalian major histocompatibility complex reflects genomic diversity and population history

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Yuhki, Naoya; O' Brien, S.J. (National Cancer Institute, Frederick, MD (USA))

1990-01-01

The major histocompatibility complex (MHC) is a multigene complex of tightly linked homologous genes that encode cell surface antigens that play a key role in immune regulation and response to foreign antigens. In most species, MHC gene products display extreme antigenic polymorphism, and their variability has been interpreted to reflect an adaptive strategy for accommodating rapidly evolving infectious agents that periodically afflict natural populations. Determination of the extent of MHC variation has been limited to populations in which skin grafting is feasible or for which serological reagents have been developed. The authors present here a quantitative analysis of restriction fragment length polymorphism of MHC class I genes in several mammalian species (cats, rodents, humans) known to have very different levels of genetic diversity based on functional MHC assays and on allozyme surveys. When homologous class I probes were employed, a notable concordance was observed between the extent of MHC restriction fragment variation and functional MHC variation detected by skin grafts or genome-wide diversity estimated by allozyme screens. These results confirm the genetically depauperate character of the African cheetah, Acinonyx jubatus, and the Asiatic lion, Panthera leo persica; further, they support the use of class I MHC molecular reagents in estimating the extent and character of genetic diversity in natural populations.

DNA variation of the mammalian major histocompatibility complex reflects genomic diversity and population history

International Nuclear Information System (INIS)

Yuhki, Naoya; O'Brien, S.J.

1990-01-01

The major histocompatibility complex (MHC) is a multigene complex of tightly linked homologous genes that encode cell surface antigens that play a key role in immune regulation and response to foreign antigens. In most species, MHC gene products display extreme antigenic polymorphism, and their variability has been interpreted to reflect an adaptive strategy for accommodating rapidly evolving infectious agents that periodically afflict natural populations. Determination of the extent of MHC variation has been limited to populations in which skin grafting is feasible or for which serological reagents have been developed. The authors present here a quantitative analysis of restriction fragment length polymorphism of MHC class I genes in several mammalian species (cats, rodents, humans) known to have very different levels of genetic diversity based on functional MHC assays and on allozyme surveys. When homologous class I probes were employed, a notable concordance was observed between the extent of MHC restriction fragment variation and functional MHC variation detected by skin grafts or genome-wide diversity estimated by allozyme screens. These results confirm the genetically depauperate character of the African cheetah, Acinonyx jubatus, and the Asiatic lion, Panthera leo persica; further, they support the use of class I MHC molecular reagents in estimating the extent and character of genetic diversity in natural populations

HUMAN DEVELOPMENT, COGNITION AND SCHOOL EDUCATION: REFLECTIONS BELOW THE HISTORICAL-CULTURAL APPROACH

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Solange Maria Alves

2016-07-01

Full Text Available This text is fruit of studies, reflections and dialogues developed with graduate and post-graduate students inteaching and research coordinated by me, allocated in the research group: Human Development, Culture and Education, in rows : Language, Learning and Development and Imaginary Production and Creative Education. Over several years, the task of educational coordinating processes of teaching and research, allowed the construction of synthesis (always provisional, presented here. Having as a foundation the historic-cultural theory of Vygotsky and collaborators, the text reflects about human development, cognition and school education, pursuing the thesis that cognition is human development. To do this, search, in theoretical foundations of historical-cultural conception, the key elements that explain the process by which the biological becomes socio-historical, it takes up more carefully in the explicit about Vygotsky translates as plans or genetic fields of human development, increase the reflection articulating the categories: labor and language.

Human polyomavirus JC variants in Papua New Guinea and Guam reflect ancient population settlement and viral evolution.

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Ryschkewitsch, C F; Friedlaender, J S; Mgone, C S; Jobes, D V; Agostini, H T; Chima, S C; Alpers, M P; Koki, G; Yanagihara, R; Stoner, G L

2000-07-01

The peopling of the Pacific was a complex sequence of events that is best reconstructed by reconciling insights from various disciplines. Here we analyze the human polyomavirus JC (JCV) in Highlanders of Papua New Guinea (PNG), in Austronesian-speaking Tolai people on the island of New Britain, and in nearby non-Austronesian-speaking Baining people. We also characterize JCV from the Chamorro of Guam, a Micronesian population. All JCV strains from PNG and Guam fall within the broad Asian group previously defined in the VP1 gene as Type 2 or Type 7, but the PNG strains were distinct from both genotypes. Among the Chamorro JCV samples, 8 strains (Guam-1) were like the Type 7 strains found in Southeast Asia, while nine strains (Guam-2) were distinct from both the mainland strains and most PNG strains. We identified three JCV variants within Papua New Guinea (PNG-1, PNG-2 and PNG-3), but none of the Southeast Asian (Type 7) strains. PNG-1 strains were present in all three populations (Highlanders and the Baining and Tolai of New Britain), but PNG-2 strains were restricted to the Highlanders. Their relative lack of DNA sequence variation suggests that they arose comparatively recently. The single PNG-3 strain, identified in an Austronesian-speaking Tolai individual, was closely related to the Chamorro variants (Guam-2), consistent with a common Austronesian ancestor. In PNG-2 variants a complex regulatory region mutation inserts a duplication into a nearby deletion, a change reminiscent of those seen in the brains of progressive multifocal leukoencephalopathy patients. This is the first instance of a complex JCV rearrangement circulating in a human population.

Cultural inter-population differences do not reflect biological distances: an example of interdisciplinary analysis of populations from Eastern Adriatic coast.

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Bašić, Željana; Fox, Ayano R; Anterić, Ivana; Jerković, Ivan; Polašek, Ozren; Anđelinović, Šimun; Holland, Mitchell M; Primorac, Dragan

2015-06-01

To compare the population group from the Šopot graveyard with population groups from traditional Croatian medieval graveyards by using anthropological, craniometrics, and mitochondrial (mtDNA) analysis and to examine if the cultural differences between population groups reflect biological differences. We determined sex, age at death, pathological, and traumatic changes of skeletal remains from the Šopot graveyard and compared them with a cumulative medieval sample from the same region. We also performed principal component analysis to compare skeletal remains from Šopot with those from Ostrovica and other Central European samples according to 8 cranial measurements. Finally, we compared 46 skeletons from Šopot with medieval (Ostrovica) and contemporary populations using mDNA haplogroup profiling. The remains from Šopot were similar to the cumulative sample in lifestyle and quality of life markers. Principal component analysis showed that they were closely related to Eastern Adriatic coast sites (including Ostrovica and Šopot) in terms of cranial morphology, indicating similar biological makeup. According to mDNA testing, Šopot population showed no significant differences in the haplogroup prevalence from either medieval or contemporary populations. This study shows that the Šopot population does not significantly differ from other medieval populations from this area. Besides similar quality of life markers, these populations also had similar biological markers. Substantial archeological differences can therefore be attributed to apparent cultural influences, which in this case do not reflect biological differences.

Reflections on the ethics of recruiting foreign-trained human resources for health

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Labonté Ronald

2011-01-01

Full Text Available Abstract Background Developed countries' gains in health human resources (HHR from developing countries with significantly lower ratios of health workers have raised questions about the ethics or fairness of recruitment from such countries. By attracting and/or facilitating migration for foreign-trained HHR, notably those from poorer, less well-resourced nations, recruitment practices and policies may be compromising the ability of developing countries to meet the health care needs of their own populations. Little is known, however, about actual recruitment practices. In this study we focus on Canada (a country with a long reliance on internationally trained HHR and recruiters working for Canadian health authorities. Methods We conducted interviews with health human resources recruiters employed by Canadian health authorities to describe their recruitment practices and perspectives and to determine whether and how they reflect ethical considerations. Results and discussion We describe the methods that recruiters used to recruit foreign-trained health professionals and the systemic challenges and policies that form the working context for recruiters and recruits. HHR recruiters' reflections on the global flow of health workers from poorer to richer countries mirror much of the content of global-level discourse with regard to HHR recruitment. A predominant market discourse related to shortages of HHR outweighed discussions of human rights and ethical approaches to recruitment policy and action that consider global health impacts. Conclusions We suggest that the concept of corporate social responsibility may provide a useful approach at the local organizational level for developing policies on ethical recruitment. Such local policies and subsequent practices may inform public debate on the health equity implications of the HHR flows from poorer to richer countries inherent in the global health worker labour market, which in turn could influence

Reflections on the ethics of recruiting foreign-trained human resources for health.

Science.gov (United States)

Runnels, Vivien; Labonté, Ronald; Packer, Corinne

2011-01-20

Developed countries' gains in health human resources (HHR) from developing countries with significantly lower ratios of health workers have raised questions about the ethics or fairness of recruitment from such countries. By attracting and/or facilitating migration for foreign-trained HHR, notably those from poorer, less well-resourced nations, recruitment practices and policies may be compromising the ability of developing countries to meet the health care needs of their own populations. Little is known, however, about actual recruitment practices. In this study we focus on Canada (a country with a long reliance on internationally trained HHR) and recruiters working for Canadian health authorities. We conducted interviews with health human resources recruiters employed by Canadian health authorities to describe their recruitment practices and perspectives and to determine whether and how they reflect ethical considerations. We describe the methods that recruiters used to recruit foreign-trained health professionals and the systemic challenges and policies that form the working context for recruiters and recruits. HHR recruiters' reflections on the global flow of health workers from poorer to richer countries mirror much of the content of global-level discourse with regard to HHR recruitment. A predominant market discourse related to shortages of HHR outweighed discussions of human rights and ethical approaches to recruitment policy and action that consider global health impacts. We suggest that the concept of corporate social responsibility may provide a useful approach at the local organizational level for developing policies on ethical recruitment. Such local policies and subsequent practices may inform public debate on the health equity implications of the HHR flows from poorer to richer countries inherent in the global health worker labour market, which in turn could influence political choices at all government and health system levels.

Reflections on the human prospect

International Nuclear Information System (INIS)

Malone, T.F.

1995-01-01

World population and the global economy are expanding in a manner that is propelling civilization along a path that is unsustainable, inequitable, and unstable. A concerted, global effort to discover, integrate, disseminate, and apply knowledge about the natural world and human behavior would change this trajectory to a path of sustainable human development. This path would point toward the vision of a society in which the basic human needs and an equitable share of life's amenities could be met by successive generations while maintaining in perpetuity a health, physically attractive, and biologically productive environment. The scholarly community is urged to provide impetus for the pursuit of this vision. An unprecedented degree of collaboration among the disciplines will be necessary. New modes of communication and cooperation among the major sectors of society will have to be fashioned. Knowledge will become an organizing principle for society in the twenty-first century. Climate change has resulted from continuing economic and demographic growth. To stabilize world climate, the emission of greenhouse gases must be controlled. 57 refs

Analyzing reflectance spectra of human skin in legal medicine

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Belenki, Liudmila; Sterzik, Vera; Schulz, Katharina; Bohnert, Michael

2013-01-01

Our current research in the framework of an interdisciplinary project focuses on modelling the dynamics of the hemoglobin reoxygenation process in post-mortem human skin by reflectance spectrometry. The observations of reoxygenation of hemoglobin in livores after postmortem exposure to a cold environment relate the reoxygenation to the commonly known phenomenon that the color impression of livores changes from livid to pink under low ambient temperatures. We analyze the spectra with respect to a physical model describing the optical properties of human skin, discuss the dynamics of the reoxygenation, and propose a phenomenological model for reoxygenation. For additional characterization of the reflectance spectra, the curvature of the local minimum and maximum in the investigated spectral range is considered. There is a strong correlation between the curvature of specra at a wavelength of 560 nm and the concentration of O2-Hb. The analysis is carried out via C programs, as well as MySQL database queries in Java EE, JDBC, Matlab, and Python.

Writing, self-reflection, and medical school performance: the Human Context of Health Care.

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Stephens, Mark B; Reamy, Brian V; Anderson, Denise; Olsen, Cara; Hemmer, Paul A; Durning, Steven J; Auster, Simon

2012-09-01

Finding ways to improve communication and self-reflection skills is an important element of medical education and continuing professional development. This study examines the relationship between self-reflection and educational outcomes. We correlate performance in a preclinical course that focuses on self-reflection as it relates to contextual elements of patient care (Human Context of Health Care), with educational measures such as overall grade point average, clinical clerkship scores, and Medical College Admission Test (MCAT) scores. Student performance in Human Context of Health Care correlated with MCAT-Verbal scores, MCAT-writing sample scores, clerkship grades, and overall medical school grade point average (R = 0.3; p self-reflection skills are often neglected in undergraduate medical curricula. Our findings suggest that these skills are important and correlate with recognized long-term educational outcomes.

DNA methylation-based variation between human populations.

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Kader, Farzeen; Ghai, Meenu

2017-02-01

Several studies have proved that DNA methylation affects regulation of gene expression and development. Epigenome-wide studies have reported variation in methylation patterns between populations, including Caucasians, non-Caucasians (Blacks), Hispanics, Arabs, and numerous populations of the African continent. Not only has DNA methylation differences shown to impact externally visible characteristics, but is also a potential biomarker for underlying racial health disparities between human populations. Ethnicity-related methylation differences set their mark during early embryonic development. Genetic variations, such as single-nucleotide polymorphisms and environmental factors, such as age, dietary folate, socioeconomic status, and smoking, impacts DNA methylation levels, which reciprocally impacts expression of phenotypes. Studies show that it is necessary to address these external influences when attempting to differentiate between populations since the relative impacts of these factors on the human methylome remain uncertain. The present review summarises several reported attempts to establish the contribution of differential DNA methylation to natural human variation, and shows that DNA methylation could represent new opportunities for risk stratification and prevention of several diseases amongst populations world-wide. Variation of methylation patterns between human populations is an exciting prospect which inspires further valuable research to apply the concept in routine medical and forensic casework. However, trans-generational inheritance needs to be quantified to decipher the proportion of variation contributed by DNA methylation. The future holds thorough evaluation of the epigenome to understand quantification, heritability, and the effect of DNA methylation on phenotypes. In addition, methylation profiling of the same ethnic groups across geographical locations will shed light on conserved methylation differences in populations.

Influence of probe pressure on diffuse reflectance spectra of human skin measured in vivo

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Popov, Alexey P.; Bykov, Alexander V.; Meglinski, Igor V.

2017-11-01

Mechanical pressure superficially applied on the human skin surface by a fiber-optic probe influences the spatial distribution of blood within the cutaneous tissues. Upon gradual load of weight on the probe, a stepwise increase in the skin reflectance spectra is observed. The decrease in the load follows the similar inverse staircase-like tendency. The observed stepwise reflectance spectra changes are due to, respectively, sequential extrusion of blood from the topical cutaneous vascular beds and their filling afterward. The obtained results are confirmed by Monte Carlo modeling. This implies that pressure-induced influence during the human skin diffuse reflectance spectra measurements in vivo should be taken into consideration, in particular, in the rapidly developing area of wearable gadgets for real-time monitoring of various human body parameters.

In vitro motility of cells from human epidermoid carcinomas. A study by phase-contrast and reflection-contrast cinematography.

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Haemmerli, G; Sträuli, P

1981-05-15

The motile behavior of six cell lines derived from human squamous carcinomas (two from the larynx, four from the tongue) was studied by cinematography under phase- and reflection-contrast illumination. The recorded cell activities consist in spreading, stationary and translocation motility, and aggregate formation. Within this common pattern, quantitative modifications ("sub-pattern") are stable properties of the individual cells lines. Such modifications are particularly evident with regard to the dynamic texture of the aggregates which ranges from loose, netlike structures to compact islands with smooth borders. Accordingly, the intensity of cell traffic within and around the aggregates varies considerably. It is discussed to what extent the in vitro motility of the carcinoma cell populations reflects their behavior in the organism and thus the significance of cell movements for invasion.

Human population growth offsets climate-driven increase in woody vegetation in sub-Saharan Africa

DEFF Research Database (Denmark)

Brandt, Martin Stefan; Rasmussen, Kjeld; Peñuelas, Josep

2017-01-01

The rapidly growing human population in sub-Saharan Africa generates increasing demand for agricultural land and forest products, which presumably leads to deforestation. Conversely, a greening of African drylands has been reported, but this has been difficult to associate with changes in woody...... an increase in woody cover largely in drylands, and 11% had a decrease (2,150,000 km2), mostly in humid zones. Increases in woody cover were associated with low population growth, and were driven by increases in CO2 in the humid zones and by increases in precipitation in drylands, whereas decreases in woody...... cover were associated with high population growth. The spatially distinct pattern of these opposing trends reflects, first, the natural response of vegetation to precipitation and atmospheric CO2, and second, deforestation in humid areas, minor in size but important for ecosystem services...

Geographic distribution of methyltransferases of Helicobacter pylori: evidence of human host population isolation and migration

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Vítor Jorge MB

2009-09-01

Full Text Available Abstract Background Helicobacter pylori colonizes the human stomach and is associated with gastritis, peptic ulcer, and gastric cancer. This ubiquitous association between H. pylori and humans is thought to be present since the origin of modern humans. The H. pylori genome encodes for an exceptional number of restriction and modifications (R-M systems. To evaluate if R-M systems are an adequate tool to determine the geographic distribution of H. pylori strains, we typed 221 strains from Africa, America, Asia, and Europe, and evaluated the expression of different 29 methyltransferases. Results Independence tests and logistic regression models revealed that ten R-M systems correlate with geographical localization. The distribution pattern of these methyltransferases may have been originated by co-divergence of regional H. pylori after its human host migrated out of Africa. The expression of specific methyltransferases in the H. pylori population may also reflect the genetic and cultural background of its human host. Methyltransferases common to all strains, M. HhaI and M. NaeI, are likely conserved in H. pylori, and may have been present in the bacteria genome since the human diaspora out of Africa. Conclusion This study indicates that some methyltransferases are useful geomarkers, which allow discrimination of bacterial populations, and that can be added to our tools to investigate human migrations.

Reflectance diffuse optical tomography. Its application to human brain mapping

International Nuclear Information System (INIS)

Ueda, Yukio; Yamanaka, Takeshi; Yamashita, Daisuke; Suzuki, Toshihiko; Ohmae, Etsuko; Oda, Motoki; Yamashita, Yutaka

2005-01-01

We report the successful application of reflectance diffuse optical tomography (DOT) using near-infrared light with the new reconstruction algorithm that we developed to the observation of regional hemodynamic changes in the brain under specific mental tasks. Our results reveal the heterogeneous distribution of oxyhemoglobin and deoxyhemoglobin in the brain, showing complementary images of oxyhemoglobin and deoxyhemoglobin changes in certain regions. We conclude that our reflectance DOT has practical potential for human brain mapping, as well as in the diagnostic imaging of brain diseases. (author)

Human object-similarity judgments reflect and transcend the primate-IT object representation

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Marieke eMur

2013-03-01

Full Text Available Primate inferior temporal (IT cortex is thought to contain a high-level representation of objects at the interface between vision and semantics. This suggests that the perceived similarity of real-world objects might be predicted from the IT representation. Here we show that objects that elicit similar activity patterns in human IT tend to be judged as similar by humans. The IT representation explained the human judgments better than early visual cortex, other ventral stream regions, and a range of computational models. Human similarity judgments exhibited category clusters that reflected several categorical divisions that are prevalent in the IT representation of both human and monkey, including the animate/inanimate and the face/body division. Human judgments also reflected the within-category representation of IT. However, the judgments transcended the IT representation in that they introduced additional categorical divisions. In particular, human judgments emphasized human-related additional divisions between human and nonhuman animals and between man-made and natural objects. Human IT was more similar to monkey IT than to human judgments. One interpretation is that IT has evolved visual feature detectors that distinguish between animates and inanimates and between faces and bodies because these divisions are fundamental to survival and reproduction for all primate species, and that other brain systems serve to more flexibly introduce species-dependent and evolutionarily more recent divisions.

Innovation and the growth of human population.

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Weinberger, V P; Quiñinao, C; Marquet, P A

2017-12-05

Biodiversity is sustained by and is essential to the services that ecosystems provide. Different species would use these services in different ways, or adaptive strategies, which are sustained in time by continuous innovations. Using this framework, we postulate a model for a biological species ( Homo sapiens ) in a finite world where innovations, aimed at increasing the flux of ecosystem services (a measure of habitat quality), increase with population size, and have positive effects on the generation of new innovations (positive feedback) as well as costs in terms of negatively affecting the provision of ecosystem services. We applied this model to human populations, where technological innovations are driven by cumulative cultural evolution. Our model shows that depending on the net impact of a technology on the provision of ecosystem services ( θ ), and the strength of technological feedback ( ξ ), different regimes can result. Among them, the human population can fill the entire planet while maximizing their well-being, but not exhaust ecosystem services. However, this outcome requires positive or green technologies that increase the provision of ecosystem services with few negative externalities or environmental costs, and that have a strong positive feedback in generating new technologies of the same kind. If the feedback is small, then the technological stock can collapse together with the human population. Scenarios where technological innovations generate net negative impacts may be associated with a limited technological stock as well as a limited human population at equilibrium and the potential for collapse. The only way to fill the planet with humans under this scenario of negative technologies is by reducing the technological stock to a minimum. Otherwise, the only feasible equilibrium is associated with population collapse. Our model points out that technological innovations per se may not help humans to grow and dominate the planet. Instead

Effects of snow-reflected light levels on human visual comfort.

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Yilmaz, Hasan; Demircioglu Yildiz, Nalan; Yilmaz, Sevgi

2008-09-01

The intensity of the sunlight reflected by the snow-covered surfaces is so high that it may disturb humans many times. This study aims to determine the reflected sunlight intensities from snow covered areas at points near (at a distance of 2 m) and under an individual tree and among trees (in the forest area) by accepting the open area as control; the reducing effects of the plant materials on reflected sunlight in percentage by comparing with the values of the open (control) area; and critical reflected sunlight threshold values for human visual comfort. The study was carried out over 22 clear and calm, i.e. sky was cloudless and wind was calm, days between the 1st and 31st days of January 2004, at 8:30 in the morning, at 12:30 at noon and at 14:30 in the afternoon in Erzurum. In order to determine the discomforting light intensity levels, 25 females and 26 male (totally 51) student subjects whose mean age was 20 and who had no visual disorders were selected. Considering the open area as control, mean reflected sunlight reducing effects were found to be 19.0, 66.0 and 82.7% for the 2 m near a tree, under a tree, and forest area, respectively. According to the responses of 51 subjects in the study, visually "very comfortable" range is between 5,000 and 8,000 lx; "comfortable" range is between 11,000 and 75,000 lx (mostly at 12,000 lx); "uncomfortable" condition is above the light intensity value of 43,000 lx and "very uncomfortable" condition is above the intensity of 80,000 lx. Great majority of the subjects (91%) found the value of 103,000 lx to be "very uncomfortable." As it is not an applicable way to use the great and dense tree masses in the cities, at least individual trees should be used along the main pedestrian axels in the cities having the same features with Erzurum to prevent the natural light pollution and discomforting effects of the snow-reflected sunlight.

Human heredity after 1945: moving populations centre stage.

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Bangham, Jenny; de Chadarevian, Soraya

2014-09-01

The essays in this issue look at the contested history of human heredity after 1945 from a new analytical angle, that of populations and the ways in which they were constructed and studied. One consequence of this approach is that we do not limit our attention to the disciplinary study of genetics. After the Second World War, populations became a central topic for an array of fields, including demography, anthropology, epidemiology, and public health. Human heredity had a role in all of these: demographers carried out mental surveys in efforts to distinguish hereditary from environmental factors, doctors screened newborns and tested pregnant women for chromosome disorders; anthropologists collected blood from remote locations to gain insights into the evolutionary history of human populations; geneticists monitored people exposed to radiation. Through this work, populations were labelled as clinical, normal, primitive, pure, vulnerable or exotic. We ask: how were populations chosen, who qualified as members, and how was the study of human heredity shaped by technical, institutional and geopolitical conditions? By following the practical and conceptual work to define populations as objects of research, the essays trace the circulation of practices across different fields and contexts, bringing into view new actors, institutions, and geographies. By doing so the collection shows how human heredity research was linked to the broader politics of the postwar world, one profoundly conditioned by Cold War tensions, by nationalist concerns, by colonial and post-colonial struggles, by modernisation projects and by a new internationalism. Copyright © 2014 Elsevier Ltd. All rights reserved.

Chromosome surveys of human populations: between epidemiology and anthropology.

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de Chadarevian, Soraya

2014-09-01

It is commonly held that after 1945 human genetics turned medical and focussed on the individual rather than on the study of human populations that had become discredited. However, a closer look at the research practices at the time quickly reveals that human population studies, using old and new tools, prospered in this period. The essay focuses on the rise of chromosome analysis as a new tool for the study of human populations. It reviews a broad array of population studies ranging from newborn screening programmes to studies of isolated or 'primitive' people. Throughout, it highlights the continuing role of concerns and opportunities raised by the propagation of atomic energy for civilian and military uses, the collection of large data bases and computers, and the role of international organisations like the World Health Organisation and the International Biological Programme in shaping research agendas and carving out a space for human heredity in the postwar era. Copyright © 2014 Elsevier Ltd. All rights reserved.

The challenges of human population ageing

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Sander, Miriam; Oxlund, Bjarke; Jespersen, Astrid; Krasnik, Allan; Mortensen, Erik Lykke; Westendorp, Rudi Gerardus Johannes; Rasmussen, Lene Juel

2015-01-01

The 20th century saw an unprecedented increase in average human lifespan as well as a rapid decline in human fertility in many countries of the world. The accompanying worldwide change in demographics of human populations is linked to unanticipated and unprecedented economic, cultural, medical, social, public health and public policy challenges, whose full implications on a societal level are only just beginning to be fully appreciated. Some of these implications are discussed in this commentary, an outcome of Cultures of Health and Ageing, a conference co-sponsored by the University of Copenhagen (UCPH) and the Center for Healthy Ageing at UCPH, which took place on 20–21 June 2014 in Copenhagen, Denmark. Questions discussed here include the following: what is driving age-structural change in human populations? how can we create ‘age-friendly’ societies and promote ‘ageing-in-community’? what tools will effectively promote social engagement and prevent social detachment among older individuals? is there a risk that further extension of human lifespan would be a greater burden to the individual and to society than is warranted by the potential benefit of longer life? PMID:25452294

Transcriptome sequencing from diverse human populations reveals differentiated regulatory architecture.

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Alicia R Martin

2014-08-01

Full Text Available Large-scale sequencing efforts have documented extensive genetic variation within the human genome. However, our understanding of the origins, global distribution, and functional consequences of this variation is far from complete. While regulatory variation influencing gene expression has been studied within a handful of populations, the breadth of transcriptome differences across diverse human populations has not been systematically analyzed. To better understand the spectrum of gene expression variation, alternative splicing, and the population genetics of regulatory variation in humans, we have sequenced the genomes, exomes, and transcriptomes of EBV transformed lymphoblastoid cell lines derived from 45 individuals in the Human Genome Diversity Panel (HGDP. The populations sampled span the geographic breadth of human migration history and include Namibian San, Mbuti Pygmies of the Democratic Republic of Congo, Algerian Mozabites, Pathan of Pakistan, Cambodians of East Asia, Yakut of Siberia, and Mayans of Mexico. We discover that approximately 25.0% of the variation in gene expression found amongst individuals can be attributed to population differences. However, we find few genes that are systematically differentially expressed among populations. Of this population-specific variation, 75.5% is due to expression rather than splicing variability, and we find few genes with strong evidence for differential splicing across populations. Allelic expression analyses indicate that previously mapped common regulatory variants identified in eight populations from the International Haplotype Map Phase 3 project have similar effects in our seven sampled HGDP populations, suggesting that the cellular effects of common variants are shared across diverse populations. Together, these results provide a resource for studies analyzing functional differences across populations by estimating the degree of shared gene expression, alternative splicing, and

The episode of genetic drift defining the migration of humans out of Africa is derived from a large east African population size.

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Nuha Elhassan

Full Text Available Human genetic variation particularly in Africa is still poorly understood. This is despite a consensus on the large African effective population size compared to populations from other continents. Based on sequencing of the mitochondrial Cytochrome C Oxidase subunit II (MT-CO2, and genome wide microsatellite data we observe evidence suggesting the effective size (Ne of humans to be larger than the current estimates, with a foci of increased genetic diversity in east Africa, and a population size of east Africans being at least 2-6 fold larger than other populations. Both phylogenetic and network analysis indicate that east Africans possess more ancestral lineages in comparison to various continental populations placing them at the root of the human evolutionary tree. Our results also affirm east Africa as the likely spot from which migration towards Asia has taken place. The study reflects the spectacular level of sequence variation within east Africans in comparison to the global sample, and appeals for further studies that may contribute towards filling the existing gaps in the database. The implication of these data to current genomic research, as well as the need to carry out defined studies of human genetic variation that includes more African populations; particularly east Africans is paramount.

Integration of effects on human populations

International Nuclear Information System (INIS)

Harwell, M.A.; Harwell, C.C.

1985-01-01

It seems possible that several hundred millions of humans could die from the direct effects of nuclear war. The indirect effects could result in the loss of one to several billions of humans. How close the latter projection would come to loss of all humans is problematical, but the current best estimation is that this result would not follow from the physical and societal perturbations currently projected to occur after a large-scale nuclear war. One important issue of scale to keep in mind is the difference between estimating that on a global scale the bases for human support would be undetermined for a particular fraction of the population (e.g., estimating insufficient food to support more than a certain fraction of the current population), and predicting the survival strategies of small groups of people. Projections of global-scale population losses do not mean that even in those areas in which humans would be expected to die, all would suffer the same fate. No analysis have been attempted here concerning the capability of selected humans on a relatively small scale (e.g., individual, family, community level) to find a successful strategy for survival. That a person or group in a combatant country might find a way to escape the effects of radiation, societal disruptions, climatic alterations, and the host of other potential disruptions, and still continue to survive seems possible, even in devastated areas. That billions of people could do so in the absence of a sufficient food support base is impossible. Thus, one needs to distinguish carefully between possible survival strategies on a small scale, and the physical limitations of support for massive numbers of people on a large scale

Genetic evidence for a Paleolithic human population expansion in Africa

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Reich, David E.; Goldstein, David B.

1998-01-01

Human populations have undergone dramatic expansions in size, but other than the growth associated with agriculture, the dates and magnitudes of those expansions have never been resolved. Here, we introduce two new statistical tests for population expansion, which use variation at a number of unlinked genetic markers to study the demographic histories of natural populations. By analyzing genetic variation in various aboriginal populations from throughout the world, we show highly significant evidence for a major human population expansion in Africa, but no evidence of expansion outside of Africa. The inferred African expansion is estimated to have occurred between 49,000 and 640,000 years ago, certainly before the Neolithic expansions, and probably before the splitting of African and non-African populations. In showing a significant difference between African and non-African populations, our analysis supports the unique role of Africa in human evolutionary history, as has been suggested by most other genetic work. In addition, the missing signal in non-African populations may be the result of a population bottleneck associated with the emergence of these populations from Africa, as postulated in the “Out of Africa” model of modern human origins. PMID:9653150

PGG.Population: a database for understanding the genomic diversity and genetic ancestry of human populations.

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Zhang, Chao; Gao, Yang; Liu, Jiaojiao; Xue, Zhe; Lu, Yan; Deng, Lian; Tian, Lei; Feng, Qidi; Xu, Shuhua

2018-01-04

There are a growing number of studies focusing on delineating genetic variations that are associated with complex human traits and diseases due to recent advances in next-generation sequencing technologies. However, identifying and prioritizing disease-associated causal variants relies on understanding the distribution of genetic variations within and among populations. The PGG.Population database documents 7122 genomes representing 356 global populations from 107 countries and provides essential information for researchers to understand human genomic diversity and genetic ancestry. These data and information can facilitate the design of research studies and the interpretation of results of both evolutionary and medical studies involving human populations. The database is carefully maintained and constantly updated when new data are available. We included miscellaneous functions and a user-friendly graphical interface for visualization of genomic diversity, population relationships (genetic affinity), ancestral makeup, footprints of natural selection, and population history etc. Moreover, PGG.Population provides a useful feature for users to analyze data and visualize results in a dynamic style via online illustration. The long-term ambition of the PGG.Population, together with the joint efforts from other researchers who contribute their data to our database, is to create a comprehensive depository of geographic and ethnic variation of human genome, as well as a platform bringing influence on future practitioners of medicine and clinical investigators. PGG.Population is available at https://www.pggpopulation.org. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Distribution of the 3' VNTR polymorphism in the human dopamine transporter gene in world populations.

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Mitchell, R J; Howlett, S; Earl, L; White, N G; McComb, J; Schanfield, M S; Briceno, I; Papiha, S S; Osipova, L; Livshits, G; Leonard, W R; Crawford, M H

2000-04-01

A polymorphism with a variable number of tandem repeats (VNTR) found in the 3' untranslated region of the human dopamine transporter gene (DAT1) was scored in unrelated individuals drawn from 10 geographically widely dispersed populations in order to assess this marker's usefulness in human population genetics. The populations that were analyzed in this study included 4 indigenous groups of Siberia, natives of North and South America, as well as Caucasian and Oceanic groups, most of which represented small-scale societies. A total of 5 DAT1 alleles were seen overall, but only in one Siberian population, the Altai-Kizhi, were all 5 present, and in the Native Americans of Colombia the locus was monomorphic. The most common allele, DAT1*10, ranged in frequency from 52% in Greeks to 100% in South Americans. The high frequency of the DAT1*10 allele (approximately 90%) among Mongoloid groups of north and east Asia distinguishes them from most Caucasian groups. The presence of the rare DAT1*7 allele in relatively high frequency (approximately 5%) among all Siberian groups suggests a close affinity with north Asian groups, especially Mongolians. The presence of the even rarer DAT1*13 allele in one Siberian population, the Altai-Kizhi, reflects this group's long historical contact with Mongolians. The results demonstrated that the DAT1 VNTR polymorphism is useful in investigating population relationships, and that rare alleles at this locus may be particularly valuable in understanding the extent of genetic affinity between neighboring groups and in situations where admixture is suspected. However, because of both the association and linkage of this VNTR locus with attention-deficit hyperactivity disorder (ADHD) in children, and its highly restricted polymorphism (usually 3 alleles) in most human groups, the possibility of selection constraints on the DAT1 gene cannot be ignored.

Genotyping of human lice suggests multiple emergencies of body lice from local head louse populations.

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Wenjun Li

Full Text Available BACKGROUND: Genetic analyses of human lice have shown that the current taxonomic classification of head lice (Pediculus humanus capitis and body lice (Pediculus humanus humanus does not reflect their phylogenetic organization. Three phylotypes of head lice A, B and C exist but body lice have been observed only in phylotype A. Head and body lice have different behaviours and only the latter have been involved in outbreaks of infectious diseases including epidemic typhus, trench fever and louse borne recurrent fever. Recent studies suggest that body lice arose several times from head louse populations. METHODS AND FINDINGS: By introducing a new genotyping technique, sequencing variable intergenic spacers which were selected from louse genomic sequence, we were able to evaluate the genotypic distribution of 207 human lice. Sequence variation of two intergenic spacers, S2 and S5, discriminated the 207 lice into 148 genotypes and sequence variation of another two intergenic spacers, PM1 and PM2, discriminated 174 lice into 77 genotypes. Concatenation of the four intergenic spacers discriminated a panel of 97 lice into 96 genotypes. These intergenic spacer sequence types were relatively specific geographically, and enabled us to identify two clusters in France, one cluster in Central Africa (where a large body louse outbreak has been observed and one cluster in Russia. Interestingly, head and body lice were not genetically differentiated. CONCLUSIONS: We propose a hypothesis for the emergence of body lice, and suggest that humans with both low hygiene and head louse infestations provide an opportunity for head louse variants, able to ingest a larger blood meal (a required characteristic of body lice, to colonize clothing. If this hypothesis is ultimately supported, it would help to explain why poor human hygiene often coincides with outbreaks of body lice. Additionally, if head lice act as a reservoir for body lice, and that any social degradation in

Perspectives on Population in AP® Human Geography

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Lu, Max; Keller, Kenneth

2016-01-01

A study of human geography begins with the human population. In fact, demographic topics frequently relate to other units in the AP Human Geography course. The three main concepts elaborated upon in this article are (1) the demographic transition model, (2) Malthusian theory and its critics, and (3) pronatalist and antinatalist policies that might…

Natural selection and infectious disease in human populations

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Karlsson, Elinor K.; Kwiatkowski, Dominic P.; Sabeti, Pardis C.

2015-01-01

The ancient biological 'arms race' between microbial pathogens and humans has shaped genetic variation in modern populations, and this has important implications for the growing field of medical genomics. As humans migrated throughout the world, populations encountered distinct pathogens, and natural selection increased the prevalence of alleles that are advantageous in the new ecosystems in both host and pathogens. This ancient history now influences human infectious disease susceptibility and microbiome homeostasis, and contributes to common diseases that show geographical disparities, such as autoimmune and metabolic disorders. Using new high-throughput technologies, analytical methods and expanding public data resources, the investigation of natural selection is leading to new insights into the function and dysfunction of human biology. PMID:24776769

A Customized Vision System for Tracking Humans Wearing Reflective Safety Clothing from Industrial Vehicles and Machinery

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Mosberger, Rafael; Andreasson, Henrik; Lilienthal, Achim J.

2014-01-01

This article presents a novel approach for vision-based detection and tracking of humans wearing high-visibility clothing with retro-reflective markers. Addressing industrial applications where heavy vehicles operate in the vicinity of humans, we deploy a customized stereo camera setup with active illumination that allows for efficient detection of the reflective patterns created by the worker's safety garments. After segmenting reflective objects from the image background, the interest regions are described with local image feature descriptors and classified in order to discriminate safety garments from other reflective objects in the scene. In a final step, the trajectories of the detected humans are estimated in 3D space relative to the camera. We evaluate our tracking system in two industrial real-world work environments on several challenging video sequences. The experimental results indicate accurate tracking performance and good robustness towards partial occlusions, body pose variation, and a wide range of different illumination conditions. PMID:25264956

mtDNA variation predicts population size in humans and reveals a major Southern Asian chapter in human prehistory.

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Atkinson, Quentin D; Gray, Russell D; Drummond, Alexei J

2008-02-01

The relative timing and size of regional human population growth following our expansion from Africa remain unknown. Human mitochondrial DNA (mtDNA) diversity carries a legacy of our population history. Given a set of sequences, we can use coalescent theory to estimate past population size through time and draw inferences about human population history. However, recent work has challenged the validity of using mtDNA diversity to infer species population sizes. Here we use Bayesian coalescent inference methods, together with a global data set of 357 human mtDNA coding-region sequences, to infer human population sizes through time across 8 major geographic regions. Our estimates of relative population sizes show remarkable concordance with the contemporary regional distribution of humans across Africa, Eurasia, and the Americas, indicating that mtDNA diversity is a good predictor of population size in humans. Plots of population size through time show slow growth in sub-Saharan Africa beginning 143-193 kya, followed by a rapid expansion into Eurasia after the emergence of the first non-African mtDNA lineages 50-70 kya. Outside Africa, the earliest and fastest growth is inferred in Southern Asia approximately 52 kya, followed by a succession of growth phases in Northern and Central Asia (approximately 49 kya), Australia (approximately 48 kya), Europe (approximately 42 kya), the Middle East and North Africa (approximately 40 kya), New Guinea (approximately 39 kya), the Americas (approximately 18 kya), and a second expansion in Europe (approximately 10-15 kya). Comparisons of relative regional population sizes through time suggest that between approximately 45 and 20 kya most of humanity lived in Southern Asia. These findings not only support the use of mtDNA data for estimating human population size but also provide a unique picture of human prehistory and demonstrate the importance of Southern Asia to our recent evolutionary past.

Study of human genetic diversity : inferences on population origin and history

OpenAIRE

Haber, Marc, 1980-

2013-01-01

Patterns of human genetic diversity suggest that all modern humans originated from a small population in Africa that expanded rapidly 50,000 years ago to occupy the whole world. While moving into new environments, genetic drift and natural selection affected populations differently, creating genetic structure. By understanding the genetic structure of human populations, we can reconstruct human history and understand the genetic basis of diseases. The work presented here contributes to the on...

Limiting factors in caribou population ecology

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David R. Klein

1991-10-01

Full Text Available Caribou and wild reindeer populations fluctuate over time. On this fact there is general agreement. Factors responsible for population limitation and subsequent declines have been examined within the framework of animal population theory. There is, however, little agreement when factors limiting specific populations are generalized to Rangifer populations over broad geographic regions. Comparative examinations of wild Rangifer populations worldwide discloses that factors that have regulated those populations are highly variable between populations, apparently as a reflection of the differences in environmental variables unique to each population. Examples exist of populations where major regulating factors have been climatic extremes, predation, hunting mortality, food limitation, insects, parasites, disease, interspecific competition, and human developmental impacts or combinations of these factors. This diversity of limiting factors affecting caribou and wild reindeer populations is a reflection of the ecologial complexity of the species, a concept that has often been ignored in past efforts to reach management decisions by extrapolation from the limited localized knowledge available on the species.

Human population, grasshopper and plant species richness in European countries

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Steck, Claude E.; Pautasso, Marco

2008-11-01

Surprisingly, several studies over large scales have reported a positive spatial correlation of people and biodiversity. This pattern has important implications for conservation and has been documented for well studied taxa such as plants, amphibians, reptiles, birds and mammals. However, it is unknown whether the pattern applies also to invertebrates other than butterflies and more work is needed to establish whether the species-people relationship is explained by both variables correlating with other environmental factors. We studied whether grasshopper species richness (Orthoptera, suborder Caelifera) is related to human population size in European countries. As expected, the number of Caelifera species increases significantly with increasing human population size. But this is not the case when controlling for country area, latitude and number of plant species. Variations in Caelifera species richness are primarily associated with variations in plant species richness. Caelifera species richness also increases with decreasing mean annual precipitation, Gross Domestic Product per capita (used as an indicator for economic development) and net fertility rate of the human population. Our analysis confirms the hypothesis that the broad-scale human population-biodiversity correlations can be explained by concurrent variations in factors other than human population size such as plant species richness, environmental productivity, or habitat heterogeneity. Nonetheless, more populated countries in Europe still have more Caelifera species than less populated countries and this poses a particular challenge for conservation.

Can human populations be stabilized?

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Warren, Stephen G.

2015-02-01

Historical examples of demographic change, in China, Italy, Nigeria, Utah, Easter Island, and elsewhere, together with simple mathematics and biological principles, show that stabilizing world population before it is limited by food supply will be more difficult than is generally appreciated. United Nations population projections are wrong because they assume, in spite of the absence of necessary feedbacks, that all nations will converge rapidly to replacement-level fertility and thereafter remain at that level. Education of women and provision of contraceptives have caused dramatic reductions in fertility, but many groups, including some that are well-educated, maintain high fertility. Small groups with persistent high fertility can grow to supplant low-fertility groups, resulting in continued growth of the total population. The global average fertility rate could rise even if each country's fertility rate is falling. In some low-fertility European countries where deaths exceed births, the population continues to grow because of immigration. Producing more than two offspring is normal for all animal species with stable populations because their populations are limited by resources or predation rather than birth control. It may therefore be appropriate to view the growth of human population as the result not of excess fertility but rather of excess food.

Population Dynamics of Early Human Migration in Britain.

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Mayank N Vahia

Full Text Available Early human migration is largely determined by geography and human needs. These are both deterministic parameters when small populations move into unoccupied areas where conflicts and large group dynamics are not important. The early period of human migration into the British Isles provides such a laboratory which, because of its relative geographical isolation, may allow some insights into the complex dynamics of early human migration and interaction.We developed a simulation code based on human affinity to habitable land, as defined by availability of water sources, altitude, and flatness of land, in choosing the path of migration. Movement of people on the British island over the prehistoric period from their initial entry points was simulated on the basis of data from the megalithic period. Topographical and hydro-shed data from satellite databases was used to define habitability, based on distance from water bodies, flatness of the terrain, and altitude above sea level. We simulated population movement based on assumptions of affinity for more habitable places, with the rate of movement tempered by existing populations. We compared results of our computer simulations with genetic data and show that our simulation can predict fairly accurately the points of contacts between different migratory paths. Such comparison also provides more detailed information about the path of peoples' movement over ~2000 years before the present era.We demonstrate an accurate method to simulate prehistoric movements of people based upon current topographical satellite data. Our findings are validated by recently-available genetic data. Our method may prove useful in determining early human population dynamics even when no genetic information is available.

High-resolution copy-number variation map reflects human olfactory receptor diversity and evolution.

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Yehudit Hasin

2008-11-01

Full Text Available Olfactory receptors (ORs, which are involved in odorant recognition, form the largest mammalian protein superfamily. The genomic content of OR genes is considerably reduced in humans, as reflected by the relatively small repertoire size and the high fraction ( approximately 55% of human pseudogenes. Since several recent low-resolution surveys suggested that OR genomic loci are frequently affected by copy-number variants (CNVs, we hypothesized that CNVs may play an important role in the evolution of the human olfactory repertoire. We used high-resolution oligonucleotide tiling microarrays to detect CNVs across 851 OR gene and pseudogene loci. Examining genomic DNA from 25 individuals with ancestry from three populations, we identified 93 OR gene loci and 151 pseudogene loci affected by CNVs, generating a mosaic of OR dosages across persons. Our data suggest that approximately 50% of the CNVs involve more than one OR, with the largest CNV spanning 11 loci. In contrast to earlier reports, we observe that CNVs are more frequent among OR pseudogenes than among intact genes, presumably due to both selective constraints and CNV formation biases. Furthermore, our results show an enrichment of CNVs among ORs with a close human paralog or lacking a one-to-one ortholog in chimpanzee. Interestingly, among the latter we observed an enrichment in CNV losses over gains, a finding potentially related to the known diminution of the human OR repertoire. Quantitative PCR experiments performed for 122 sampled ORs agreed well with the microarray results and uncovered 23 additional CNVs. Importantly, these experiments allowed us to uncover nine common deletion alleles that affect 15 OR genes and five pseudogenes. Comparison to the chimpanzee reference genome revealed that all of the deletion alleles are human derived, therefore indicating a profound effect of human-specific deletions on the individual OR gene content. Furthermore, these deletion alleles may be used

Producing Neoliberal Citizens: Critical Reflections on Human Rights Education in Pakistan

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Khoja-Moolji, Shenila

2014-01-01

This paper challenges the celebratory uptake of human rights education (HRE) in postcolonial contexts by making visible the ideological and political entanglements of the discourse with neoliberal assumptions of citizenship. I draw evidence from, and critically reflect on, a specific HRE programme--a series of summer camps for girls entitled,…

Population and prehistory II: space-limited human populations in constant environments.

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Puleston, Cedric O; Tuljapurkar, Shripad

2008-09-01

We present a population model to examine the forces that determined the quality and quantity of human life in early agricultural societies where cultivable area is limited. The model is driven by the non-linear and interdependent relationships between the age distribution of a population, its behavior and technology, and the nature of its environment. The common currency in the model is the production of food, on which age-specific rates of birth and death depend. There is a single non-trivial equilibrium population at which productivity balances caloric needs. One of the most powerful controls on equilibrium hunger level is fertility control. Gains against hunger are accompanied by decreases in population size. Increasing worker productivity does increase equilibrium population size but does not improve welfare at equilibrium. As a case study we apply the model to the population of a Polynesian valley before European contact.

Human population genetics and “ancestrality” business

OpenAIRE

André Langaney

2009-01-01

Following the foundation of theoretical population genetics by Wright, Fischer, Haldane and Malécot, in the first half of the 20th century, applied human population genetics developed with great success with the improvement and accumulation of new technologies to measure genetic polymorphism, first through protein polymorphisms since the 1960’s, then through DNA typing and sequencing since the 1980’s. The field of population genetics and biological anthropology was developed by a handful of d...

Effects of bleaching agents on human enamel light reflectance.

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Markovic, Ljubisa; Fotouhi, Kasra; Lorenz, Heribert; Jordan, Rainer A; Gaengler, Peter; Zimmer, Stefan

2010-01-01

Tooth whitening has been associated with splitting-up chromogenic molecules by hydrogen peroxides. Though micromorphological alterations are well documented, little is known about optical changes as a function of shifting in wavelengths. Therefore, the aim of the current study was to measure reflectance changes after bleaching in vitro by using a spectrometer. Forty-eight enamel slabs (diameter = 5 mm) were prepared from the sound enamel of extracted human teeth that were: 1) fully impacted, 2) from juveniles ages 10 to 16 years, 3) from adults 35 to 45 years of age and 4) from seniors older than age 65. In all specimens, the baseline total reflectance measurement was performed with a computer-assisted spectrometer (Ocean Optics, Dunedin, FL, USA) within wavelengths (wl) from 430 nm to 800 nm. Four enamel samples of each age group were exposed to either 10% or 15% carbamide peroxide (Illuminé Home, Dentsply, Konstanz, Germany) or 35% hydrogen peroxide (Pola Office, SDI Limited, Victoria, Australia). After surface treatment, all slabs underwent total reflectance measurement again. Statistical analysis was calculated at wl 450, 500 and 750 nm using the Student's paired t-test and one-way variance analysis. Total reflectance significantly increased after bleaching at all enamel maturation stages, irrespective of the bleaching agent concentration, for wl 450 nm (blue) and 500 nm (green) with penamel from adults and seniors (pwhitening of the dental enamel works at different maturation stages, even in impacted teeth. This effect is irrespective of the bleaching protocol used and the bleaching agent concentration.

Hyperspectral optical imaging of human iris in vivo: characteristics of reflectance spectra

Science.gov (United States)

Medina, José M.; Pereira, Luís M.; Correia, Hélder T.; Nascimento, Sérgio M. C.

2011-07-01

We report a hyperspectral imaging system to measure the reflectance spectra of real human irises with high spatial resolution. A set of ocular prosthesis was used as the control condition. Reflectance data were decorrelated by the principal-component analysis. The main conclusion is that spectral complexity of the human iris is considerable: between 9 and 11 principal components are necessary to account for 99% of the cumulative variance in human irises. Correcting image misalignments associated with spontaneous ocular movements did not influence this result. The data also suggests a correlation between the first principal component and different levels of melanin present in the irises. It was also found that although the spectral characteristics of the first five principal components were not affected by the radial and angular position of the selected iridal areas, they affect the higher-order ones, suggesting a possible influence of the iris texture. The results show that hyperspectral imaging in the iris, together with adequate spectroscopic analyses provide more information than conventional colorimetric methods, making hyperspectral imaging suitable for the characterization of melanin and the noninvasive diagnosis of ocular diseases and iris color.

Reframing Photographic Research Methods in Human Geography: A Long-Term Reflection

Science.gov (United States)

Hall, Tim

2015-01-01

This paper offers a long-term reflection on the introduction of a photographic research project into a third-year undergraduate Human Geography module. The findings indicate that, whilst the students valued the project, it did impact on their overall performance, their evaluation of the module and the ways in which they spoke about it. The paper…

Assessing human skin with diffuse reflectance spectroscopy and colorimetry

Science.gov (United States)

Seo, InSeok; Liu, Yang; Bargo, Paulo R.; Kollias, Nikiforos

2012-02-01

Colorimetry has been used as an objective measure of perceived skin color by human eye to document and score physiological responses of the skin from external insults. CIE color space values (L*, a* and b*) are the most commonly used parameters to correlate visually perceived color attributes such as L* for pigment, a* for erythema, and b* for sallowness of the skin. In this study, we investigated the relation of Lab color scale to the amount of major skin chromophores (oxy-, deoxyhemoglobin and melanin) calculated from diffuse reflectance spectroscopy. Thirty two healthy human subjects with ages from 20 to 70 years old, skin types I-VI, were recruited for the study. DRS and colorimetry measurements were taken from the left and right cheeks, and on the right upper inner arm. The melanin content calculated from 630-700 nm range of DRS measurements was shown to correlate with the lightness of skin (L*) for most skin types. For subjects with medium-to-light complexion, melanin measured at the blue part spectrum and hemoglobin interfered on the relation of lightness of the skin color to the melanin content. The sallowness of the skin that is quantified by the melanin contribution at the blue part spectrum of DRS was found to be related to b* scale. This study demonstrates the importance of documenting skin color by assessing individual skin chromophores with diffuse reflectance spectroscopy, in comparison to colorimetry assessment.

Population issues surface at human settlements conference.

Science.gov (United States)

1996-01-01

This news brief focuses on the debate about population issues at the UN Conference on Human Settlements, held in Istanbul, Turkey, in June 1996. The Istanbul Declaration on Human Settlements was adopted by world leaders at the conference. Leaders were committed to programs to improve standards of living, the right of citizens to adequate housing, and the mobilization of new financial resources. Dr. Sadik, as Executive Director of the UN Population Fund, stressed that natural increase accounts for 60% of urban population growth. Mr. Boutros Boutros-Ghali, as UN Secretary General, stressed that over 50% of world population would live in urban centers by the year 2000, and almost 75% might do so by 2025. He indicated that all nations are interrelated; the poor and refugees from political conflict from one country travel to safer and richer countries. Dr. Sadik referred to the agreement at the 1994 International Conference on Population and Development (ICPD) on stabilizing world population in the shortest time possible. This would require meeting the needs of men and women for health, education, and the power of personal decision making. The most important item was the satisfaction of women's need for reproductive health information and services and women's power to use services. Dr. Sadik urged that women be given the right to hold and inherit property and to obtain credit. It was pointed out that the language of Habitat's plan of action on population and development issues was frequently bracketed; consequently, the plan suffered from a lack of consensus. The debate between countries would end, if the language were not bracketed. Dr. Sadik recommended family planning for developing sustainable and liveable cities.

Human migration patterns in Yemen and implications for reconstructing prehistoric population movements.

Directory of Open Access Journals (Sweden)

Aida T Miró-Herrans

Full Text Available Population migration has played an important role in human evolutionary history and in the patterning of human genetic variation. A deeper and empirically-based understanding of human migration dynamics is needed in order to interpret genetic and archaeological evidence and to accurately reconstruct the prehistoric processes that comprise human evolutionary history. Current empirical estimates of migration include either short time frames (i.e. within one generation or partial knowledge about migration, such as proportion of migrants or distance of migration. An analysis of migration that includes both proportion of migrants and distance, and direction over multiple generations would better inform prehistoric reconstructions. To evaluate human migration, we use GPS coordinates from the place of residence of the Yemeni individuals sampled in our study, their birthplaces and their parents' and grandparents' birthplaces to calculate the proportion of migrants, as well as the distance and direction of migration events between each generation. We test for differences in these values between the generations and identify factors that influence the probability of migration. Our results show that the proportion and distance of migration between females and males is similar within generations. In contrast, the proportion and distance of migration is significantly lower in the grandparents' generation, most likely reflecting the decreasing effect of technology. Based on our results, we calculate the proportion of migration events (0.102 and mean and median distances of migration (96 km and 26 km for the grandparent's generation to represent early times in human evolution. These estimates can serve to set parameter values of demographic models in model-based methods of prehistoric reconstruction, such as approximate Bayesian computation. Our study provides the first empirically-based estimates of human migration over multiple generations in a developing

21 century perspective in radiation protection of humans and human population

International Nuclear Information System (INIS)

Vassilev, G.

2003-01-01

In 21 century ionizing radiation is applied in all field of human activities. In parallel, the radiobiology and radiation medicine are developing as separate branches for the purposes of the radiation protection: for risk estimation and regulation of the human irradiation. Main features of radiation protection at the beginning of the century are: 1.Well developed conservative theoretical background, based on the linear non-threshold concept 'dose-effect' towards the carcinogenesis and genetic effects; 2. Developed international and national structures, including organizations as ICRP, UNSCEAR, ICRU, IAEA, WHO, FAO, BEIR, OECD/NEA, ILO, NCRP, NRPB etc. 3. Detailed regulative legislation for all cases of human irradiation, combines with effective control structures. Ionizing radiation is the most strictly regulated factor affecting humans among the all adverse impacts of the living environment. The expectations for the radiation protection in 21 century are: 1. A radical reassessment of the concept for low doses and the linear non-threshold concept since data for existing of a threshold on the human population level. 2. Taking into consideration of the the adaptation to the irradiation, comparable with the natural radiation background. 3. Taking into consideration of the radiation hormesis, which are now ignored by the risk theory. 4. Clarification of the questions of the genetic effects, which are not yet determined for the human population. 5. Radical solutions of the radioactive waste problem, which will be crucial for the future of the nuclear energy production. 6. Gradual overcoming of the fear from ionizing radiation, which is an important social factor

Evidence of Recent Intricate Adaptation in Human Populations.

Directory of Open Access Journals (Sweden)

Leeyoung Park

Full Text Available Recent human adaptations have shaped population differentiation in genomic regions containing putative functional variants, mostly located in predicted regulatory elements. However, their actual functionalities and the underlying mechanism of recent adaptation remain poorly understood. In the current study, regions of genes and repeats were investigated for functionality depending on the degree of population differentiation, FST or ΔDAF (a difference in derived allele frequency. The high FST in the 5´ or 3´ untranslated regions (UTRs, in particular, confirmed that population differences arose mainly from differences in regulation. Expression quantitative trait loci (eQTL analyses using lymphoblastoid cell lines indicated that the majority of the highly population-specific regions represented cis- and/or trans-eQTL. However, groups having the highest ΔDAFs did not necessarily have higher proportions of eQTL variants; in these groups, the patterns were complex, indicating recent intricate adaptations. The results indicated that East Asian (EAS and European populations (EUR experienced mutual selection pressures. The mean derived allele frequency of the high ΔDAF groups suggested that EAS and EUR underwent strong adaptation; however, the African population in Africa (AFR experienced slight, yet broad, adaptation. The DAF distributions of variants in the gene regions showed clear selective pressure in each population, which implies the existence of more recent regulatory adaptations in cells other than lymphoblastoid cell lines. In-depth analysis of population-differentiated regions indicated that the coding gene, RNF135, represented a trans-regulation hotspot via cis-regulation by the population-specific variants in the region of selective sweep. Together, the results provide strong evidence of actual intricate adaptation of human populations via regulatory manipulation.

Human population studies and the World Health Organization.

Science.gov (United States)

de Chadarevian, Soraya

2015-01-01

This essay draws attention to the role of the WHO in shaping research agendas in the biomedical sciences in the postwar era. It considers in particular the genetic studies of human populations that were pursued under the aegis of the WHO from the late 1950s to 1970s. The study provides insights into how human and medical genetics entered the agenda of the WHO. At the same time, the population studies become a focus for tracking changing notions of international relations, cooperation, and development and their impact on research in biology and medicine in the post-World War I era. After a brief discussion of the early history of the WHO and its position in Cold War politics, the essay considers the WHO program in radiation protection and heredity and how the genetic study of "vanishing" human populations and a world-wide genetic study of newborns fitted this broader agenda. It then considers in more detail the kind of support offered by the WHO for these projects. The essay highlights the role of single individuals in taking advantage of WHO support for pushing their research agendas while establishing a trend towards cooperative international projects in biology.

Alu repeats as markers for human population genetics

Energy Technology Data Exchange (ETDEWEB)

Batzer, M.A.; Alegria-Hartman, M. [Lawrence Livermore National Lab., CA (United States); Bazan, H. [Louisiana State Univ., New Orleans, LA (United States). Medical Center] [and others

1993-09-01

The Human-Specific (HS) subfamily of Alu sequences is comprised of a group of 500 nearly identical members which are almost exclusively restricted to the human genome. Individual subfamily members share an average of 97.9% nucleotide identity with each other and an average of 98.9% nucleotide identity with the HS subfamily consensus sequence. HS Alu family members are thought to be derived from a single source ``master`` gene, and have an average age of 2.8 million years. We have developed a Polymerase Chain Reaction (PCR) based assay using primers complementary to the 5 in. and 3 in. unique flanking DNA sequences from each HS Alu that allows the locus to be assayed for the presence or absence of an Alu repeat. Individual HS Alu sequences were found to be either monomorphic or dimorphic for the presence or absence of each repeat. The monomorphic HS Alu family members inserted in the human genome after the human/great ape divergence (which is thought to have occurred 4--6 million years ago), but before the radiation of modem man. The dimorphic HS Alu sequences inserted in the human genome after the radiation of modem man (within the last 200,000-one million years) and represent a unique source of information for human population genetics and forensic DNA analyses. These sites can be developed into Dimorphic Alu Sequence Tagged Sites (DASTS) for the Human Genome Project as well. HS Alu family member insertion dimorphism differs from other types of polymorphism (e.g. Variable Number of Tandem Repeat [VNTR] or Restriction Fragment Length Polymorphism [RFLP]) because individuals share HS Alu family member insertions based upon identity by descent from a common ancestor as a result of a single event which occurred one time within the human population. The VNTR and RFLP polymorphisms may arise multiple times within a population and are identical by state only.

Recent trends in local-scale marine biodiversity reflect community structure and human impacts

NARCIS (Netherlands)

Elahi, Robin; O'Connor, Mary I; Byrnes, Jarrett E K; Dunic, Jillian; Eriksson, Britas Klemens; Hensel, Marc J S; Kearns, Patrick J

2015-01-01

The modern biodiversity crisis reflects global extinctions and local introductions. Human activities have dramatically altered rates and scales of processes that regulate biodiversity at local scales [1-7]. Reconciling the threat of global biodiversity loss [2, 4, 6-9] with recent evidence of

Adaptations to local environments in modern human populations.

Science.gov (United States)

Jeong, Choongwon; Di Rienzo, Anna

2014-12-01

After leaving sub-Saharan Africa around 50000-100000 years ago, anatomically modern humans have quickly occupied extremely diverse environments. Human populations were exposed to further environmental changes resulting from cultural innovations, such as the spread of farming, which gave rise to new selective pressures related to pathogen exposures and dietary shifts. In addition to changing the frequency of individual adaptive alleles, natural selection may also shape the overall genetic architecture of adaptive traits. Here, we review recent advances in understanding the genetic architecture of adaptive human phenotypes based on insights from the studies of lactase persistence, skin pigmentation and high-altitude adaptation. These adaptations evolved in parallel in multiple human populations, providing a chance to investigate independent realizations of the evolutionary process. We suggest that the outcome of adaptive evolution is often highly variable even under similar selective pressures. Finally, we highlight a growing need for detecting adaptations that did not follow the classical sweep model and for incorporating new sources of genetic evidence such as information from ancient DNA. Copyright © 2014 Elsevier Ltd. All rights reserved.

Investigation of the Influence of Leaf Thickness on Canopy Reflectance and Physiological Traits in Upland and Pima Cotton Populations

Directory of Open Access Journals (Sweden)

Duke Pauli

2017-08-01

Full Text Available Many systems for field-based, high-throughput phenotyping (FB-HTP quantify and characterize the reflected radiation from the crop canopy to derive phenotypes, as well as infer plant function and health status. However, given the technology's nascent status, it remains unknown how biophysical and physiological properties of the plant canopy impact downstream interpretation and application of canopy reflectance data. In that light, we assessed relationships between leaf thickness and several canopy-associated traits, including normalized difference vegetation index (NDVI, which was collected via active reflectance sensors carried on a mobile FB-HTP system, carbon isotope discrimination (CID, and chlorophyll content. To investigate the relationships among traits, two distinct cotton populations, an upland (Gossypium hirsutum L. recombinant inbred line (RIL population of 95 lines and a Pima (G. barbadense L. population composed of 25 diverse cultivars, were evaluated under contrasting irrigation regimes, water-limited (WL and well-watered (WW conditions, across 3 years. We detected four quantitative trait loci (QTL and significant variation in both populations for leaf thickness among genotypes as well as high estimates of broad-sense heritability (on average, above 0.7 for both populations, indicating a strong genetic basis for leaf thickness. Strong phenotypic correlations (maximum r = −0.73 were observed between leaf thickness and NDVI in the Pima population, but not the RIL population. Additionally, estimated genotypic correlations within the RIL population for leaf thickness with CID, chlorophyll content, and nitrogen discrimination (r^gij = −0.32, 0.48, and 0.40, respectively were all significant under WW but not WL conditions. Economically important fiber quality traits did not exhibit significant phenotypic or genotypic correlations with canopy traits. Overall, our results support considering variation in leaf thickness as a potential

Will human populations be limited by food?

Science.gov (United States)

Warren, S. G.

2016-12-01

Historical examples of demographic change, in China, Italy, Nigeria, Utah, the Philippines, and elsewhere, together with simple mathematics and biological principles, show that stabilizing world population before it is limited by food supply will be more difficult than is generally appreciated. United Nations population projections are based on a logical fallacy in that they assume, in spite of the absence of necessary negative feedbacks, that all nations will converge rapidly to replacement-level fertility and thereafter remain at that level. The benign projections that have resulted from this assumption may have hindered efforts to make availability of birth-control a priority in development-aid. Education of women and provision of contraceptives have caused dramatic reductions in fertility, but many groups, including some that are well-educated, maintain high fertility. Small groups with persistent high fertility can grow to supplant low-fertility groups, resulting in continued growth of the total population. The global average fertility rate could rise even if each country's fertility rate is falling. In some low-fertility European countries where deaths exceed births, the population continues to grow because of immigration. Producing more than two offspring is normal for all animal species with stable populations, because their populations are limited by resources or predation rather than birth control. It may therefore be appropriate to view the growth of human population as the result not of excess fertility but rather of excess food. Even if the fertility rate is maintained far in excess of 2, the population cannot grow if food is limiting. Without the agricultural advances of the 20thcentury, world population could not have grown as it did from 1.7 billion in 1900 to 6 billion in 2000. The food supply may be enhanced in the future by genetic engineering and other innovations, but it may be limited by water shortage, climate change, pollution, and energy

The interaction of human population, food production, and biodiversity protection.

Science.gov (United States)

Crist, Eileen; Mora, Camilo; Engelman, Robert

2017-04-21

Research suggests that the scale of human population and the current pace of its growth contribute substantially to the loss of biological diversity. Although technological change and unequal consumption inextricably mingle with demographic impacts on the environment, the needs of all human beings-especially for food-imply that projected population growth will undermine protection of the natural world. Numerous solutions have been proposed to boost food production while protecting biodiversity, but alone these proposals are unlikely to staunch biodiversity loss. An important approach to sustaining biodiversity and human well-being is through actions that can slow and eventually reverse population growth: investing in universal access to reproductive health services and contraceptive technologies, advancing women's education, and achieving gender equality. Copyright © 2017, American Association for the Advancement of Science.

Using Population Data to Address the Human Dimensions of Environmental Change

Science.gov (United States)

D.M. Mageean; J.G. Bartlett

1999-01-01

In recent years researchers and policy makers have identified population-environment interactions as crucial to issues of ecology, economic development, and human welfare. It seems clear that human populations and demands on the environment are driving ecological change in such areas as global warming, ozone depletion, deforestation, biodiversity loss, land degradation...

Reflectance spectrometry of normal and bruised human skins: experiments and modeling

International Nuclear Information System (INIS)

Kim, Oleg; Alber, Mark; McMurdy, John; Lines, Collin; Crawford, Gregory; Duffy, Susan

2012-01-01

A stochastic photon transport model in multilayer skin tissue combined with reflectance spectroscopy measurements is used to study normal and bruised skins. The model is shown to provide a very good approximation to both normal and bruised real skin tissues by comparing experimental and simulated reflectance spectra. The sensitivity analysis of the skin reflectance spectrum to variations of skin layer thicknesses, blood oxygenation parameter and concentrations of main chromophores is performed to optimize model parameters. The reflectance spectrum of a developed bruise in a healthy adult is simulated, and the concentrations of bilirubin, blood volume fraction and blood oxygenation parameter are determined for different times as the bruise progresses. It is shown that bilirubin and blood volume fraction reach their peak values at 80 and 55 h after contusion, respectively, and the oxygenation parameter is lower than its normal value during 80 h after contusion occurred. The obtained time correlations of chromophore concentrations in developing contusions are shown to be consistent with previous studies. The developed model uses a detailed seven-layer skin approximation for contusion and allows one to obtain more biologically relevant results than those obtained with previous models using one- to three-layer skin approximations. A combination of modeling with spectroscopy measurements provides a new tool for detailed biomedical studies of human skin tissue and for age determination of contusions. (paper)

Learning about human population history from ancient and modern genomes.

Science.gov (United States)

Stoneking, Mark; Krause, Johannes

2011-08-18

Genome-wide data, both from SNP arrays and from complete genome sequencing, are becoming increasingly abundant and are now even available from extinct hominins. These data are providing new insights into population history; in particular, when combined with model-based analytical approaches, genome-wide data allow direct testing of hypotheses about population history. For example, genome-wide data from both contemporary populations and extinct hominins strongly support a single dispersal of modern humans from Africa, followed by two archaic admixture events: one with Neanderthals somewhere outside Africa and a second with Denisovans that (so far) has only been detected in New Guinea. These new developments promise to reveal new stories about human population history, without having to resort to storytelling.

Reflection coefficients of permeant molecules in human red cell suspensions.

Science.gov (United States)

Owen, J D; Eyring, E M

1975-08-01

The Staverman reflection coefficient, sigma for several permeant molecules was determined in human red cell suspensions with a Durrum stopped-flow spectrophotometer. This procedure was first used with dog, cat, and beef red cells and with human red cells. The stopped-flow technique used was similar to the rapid-flow method used by those who originally reported sigma measurements in human red cells for molecules which rapidly penetrate the red cell membrane. The sigma values we obtained agreed with those previously reported for most of the slow penetrants, except malonamide, but disagreed with all the sigma values previously reported for the rapid penetrants. We were unable to calculate an "equivalent pore radius" with our sigma data. The advantages of our equipment and our experimental procedure are discussed. Our sigma data suggest that sigma is indirectly proportional to the log of the nonelectrolyte permeability coefficient, omega. Since a similar trend has been previously shown for log omega and molar volume of the permeant molecules, a correlatioo was shown between sigma and molar volume suggesting the membrane acts as a sieve.

Anthropogenics: human influence on global and genetic homogenization of parasite populations.

Science.gov (United States)

Zarlenga, Dante S; Hoberg, Eric; Rosenthal, Benjamin; Mattiucci, Simonetta; Nascetti, Giuseppe

2014-12-01

The distribution, abundance, and diversity of life on Earth have been greatly shaped by human activities. This includes the geographic expansion of parasites; however, measuring the extent to which humans have influenced the dissemination and population structure of parasites has been challenging. In-depth comparisons among parasite populations extending to landscape-level processes affecting disease emergence have remained elusive. New research methods have enhanced our capacity to discern human impact, where the tools of population genetics and molecular epidemiology have begun to shed light on our historical and ongoing influence. Only since the 1990s have parasitologists coupled morphological diagnosis, long considered the basis of surveillance and biodiversity studies, with state-of-the-art tools enabling variation to be examined among, and within, parasite populations. Prior to this time, populations were characterized only by phenotypic attributes such as virulence, infectivity, host range, and geographical location. The advent of genetic/molecular methodologies (multilocus allozyme electrophoresis, polymerase chain reaction-DNA [PCR-DNA] fragments analysis, DNA sequencing, DNA microsatellites, single nucleotide polymorphisms, etc.) have transformed our abilities to reveal variation among, and within, populations at local, regional, landscape, and global scales, and thereby enhanced our understanding of the biosphere. Numerous factors can affect population structure among parasites, e.g., evolutionary and ecological history, mode of reproduction and transmission, host dispersal, and life-cycle complexity. Although such influences can vary considerably among parasite taxa, anthropogenic factors are demonstrably perturbing parasite fauna. Minimal genetic structure among many geographically distinct (isolated) populations is a hallmark of human activity, hastened by geographic introductions, environmental perturbation, and global warming. Accelerating

Integrating common and rare genetic variation in diverse human populations.

Science.gov (United States)

Altshuler, David M; Gibbs, Richard A; Peltonen, Leena; Altshuler, David M; Gibbs, Richard A; Peltonen, Leena; Dermitzakis, Emmanouil; Schaffner, Stephen F; Yu, Fuli; Peltonen, Leena; Dermitzakis, Emmanouil; Bonnen, Penelope E; Altshuler, David M; Gibbs, Richard A; de Bakker, Paul I W; Deloukas, Panos; Gabriel, Stacey B; Gwilliam, Rhian; Hunt, Sarah; Inouye, Michael; Jia, Xiaoming; Palotie, Aarno; Parkin, Melissa; Whittaker, Pamela; Yu, Fuli; Chang, Kyle; Hawes, Alicia; Lewis, Lora R; Ren, Yanru; Wheeler, David; Gibbs, Richard A; Muzny, Donna Marie; Barnes, Chris; Darvishi, Katayoon; Hurles, Matthew; Korn, Joshua M; Kristiansson, Kati; Lee, Charles; McCarrol, Steven A; Nemesh, James; Dermitzakis, Emmanouil; Keinan, Alon; Montgomery, Stephen B; Pollack, Samuela; Price, Alkes L; Soranzo, Nicole; Bonnen, Penelope E; Gibbs, Richard A; Gonzaga-Jauregui, Claudia; Keinan, Alon; Price, Alkes L; Yu, Fuli; Anttila, Verneri; Brodeur, Wendy; Daly, Mark J; Leslie, Stephen; McVean, Gil; Moutsianas, Loukas; Nguyen, Huy; Schaffner, Stephen F; Zhang, Qingrun; Ghori, Mohammed J R; McGinnis, Ralph; McLaren, William; Pollack, Samuela; Price, Alkes L; Schaffner, Stephen F; Takeuchi, Fumihiko; Grossman, Sharon R; Shlyakhter, Ilya; Hostetter, Elizabeth B; Sabeti, Pardis C; Adebamowo, Clement A; Foster, Morris W; Gordon, Deborah R; Licinio, Julio; Manca, Maria Cristina; Marshall, Patricia A; Matsuda, Ichiro; Ngare, Duncan; Wang, Vivian Ota; Reddy, Deepa; Rotimi, Charles N; Royal, Charmaine D; Sharp, Richard R; Zeng, Changqing; Brooks, Lisa D; McEwen, Jean E

2010-09-02

Despite great progress in identifying genetic variants that influence human disease, most inherited risk remains unexplained. A more complete understanding requires genome-wide studies that fully examine less common alleles in populations with a wide range of ancestry. To inform the design and interpretation of such studies, we genotyped 1.6 million common single nucleotide polymorphisms (SNPs) in 1,184 reference individuals from 11 global populations, and sequenced ten 100-kilobase regions in 692 of these individuals. This integrated data set of common and rare alleles, called 'HapMap 3', includes both SNPs and copy number polymorphisms (CNPs). We characterized population-specific differences among low-frequency variants, measured the improvement in imputation accuracy afforded by the larger reference panel, especially in imputing SNPs with a minor allele frequency of populations supports deeper interrogation of genomic variation and its role in human disease, and serves as a step towards a high-resolution map of the landscape of human genetic variation.

A Formidable Task: Reflections on obtaining legal empirical evidence on human trafficking in Canada

OpenAIRE

Hayli Millar; Tamara O'Doherty; Katrin Roots

2017-01-01

This article explores the experiences, challenges and findings of two empirical research studies examining Canada’s legal efforts to combat human trafficking. The authors outline the methodologies of their respective studies and reflect on some of the difficulties they faced in obtaining empirical data on human trafficking court cases and legal proceedings. Ultimately, the authors found that Canadian trafficking case law developments are in their early stages with very few convictions, despit...

Statistical Processing Algorithms for Human Population Databases

Directory of Open Access Journals (Sweden)

Camelia COLESCU

2012-01-01

Full Text Available The article is describing some algoritms for statistic functions aplied to a human population database. The samples are specific for the most interesting periods, when the evolution of statistical datas has spectacolous value. The article describes the most usefull form of grafical prezentation of the results

Improved physiologically based pharmacokinetic model for oral exposures to chromium in mice, rats, and humans to address temporal variation and sensitive populations.

Science.gov (United States)

Kirman, C R; Suh, M; Proctor, D M; Hays, S M

2017-06-15

A physiologically based pharmacokinetic (PBPK) model for hexavalent chromium [Cr(VI)] in mice, rats, and humans developed previously (Kirman et al., 2012, 2013), was updated to reflect an improved understanding of the toxicokinetics of the gastrointestinal tract following oral exposures. Improvements were made to: (1) the reduction model, which describes the pH-dependent reduction of Cr(VI) to Cr(III) in the gastrointestinal tract under both fasted and fed states; (2) drinking water pattern simulations, to better describe dosimetry in rodents under the conditions of the NTP cancer bioassay; and (3) parameterize the model to characterize potentially sensitive human populations. Important species differences, sources of non-linear toxicokinetics, and human variation are identified and discussed within the context of human health risk assessment. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Parallel selection on TRPV6 in human populations.

Science.gov (United States)

Hughes, David A; Tang, Kun; Strotmann, Rainer; Schöneberg, Torsten; Prenen, Jean; Nilius, Bernd; Stoneking, Mark

2008-02-27

We identified and examined a candidate gene for local directional selection in Europeans, TRPV6, and conclude that selection has acted on standing genetic variation at this locus, creating parallel soft sweep events in humans. A novel modification of the extended haplotype homozygosity (EHH) test was utilized, which compares EHH for a single allele across populations, to investigate the signature of selection at TRPV6 and neighboring linked loci in published data sets for Europeans, Asians and African-Americans, as well as in newly-obtained sequence data for additional populations. We find that all non-African populations carry a signature of selection on the same haplotype at the TRPV6 locus. The selective footprints, however, are significantly differentiated between non-African populations and estimated to be younger than an ancestral population of non-Africans. The possibility of a single selection event occurring in an ancestral population of non-Africans was tested by simulations and rejected. The putatively-selected TRPV6 haplotype contains three candidate sites for functional differences, namely derived non-synonymous substitutions C157R, M378V and M681T. Potential functional differences between the ancestral and derived TRPV6 proteins were investigated by cloning the ancestral and derived forms, transfecting cell lines, and carrying out electrophysiology experiments via patch clamp analysis. No statistically-significant differences in biophysical channel function were found, although one property of the protein, namely Ca(2+) dependent inactivation, may show functionally relevant differences between the ancestral and derived forms. Although the reason for selection on this locus remains elusive, this is the first demonstration of a widespread parallel selection event acting on standing genetic variation in humans, and highlights the utility of between population EHH statistics.

Parallel selection on TRPV6 in human populations.

Directory of Open Access Journals (Sweden)

David A Hughes

Full Text Available We identified and examined a candidate gene for local directional selection in Europeans, TRPV6, and conclude that selection has acted on standing genetic variation at this locus, creating parallel soft sweep events in humans. A novel modification of the extended haplotype homozygosity (EHH test was utilized, which compares EHH for a single allele across populations, to investigate the signature of selection at TRPV6 and neighboring linked loci in published data sets for Europeans, Asians and African-Americans, as well as in newly-obtained sequence data for additional populations. We find that all non-African populations carry a signature of selection on the same haplotype at the TRPV6 locus. The selective footprints, however, are significantly differentiated between non-African populations and estimated to be younger than an ancestral population of non-Africans. The possibility of a single selection event occurring in an ancestral population of non-Africans was tested by simulations and rejected. The putatively-selected TRPV6 haplotype contains three candidate sites for functional differences, namely derived non-synonymous substitutions C157R, M378V and M681T. Potential functional differences between the ancestral and derived TRPV6 proteins were investigated by cloning the ancestral and derived forms, transfecting cell lines, and carrying out electrophysiology experiments via patch clamp analysis. No statistically-significant differences in biophysical channel function were found, although one property of the protein, namely Ca(2+ dependent inactivation, may show functionally relevant differences between the ancestral and derived forms. Although the reason for selection on this locus remains elusive, this is the first demonstration of a widespread parallel selection event acting on standing genetic variation in humans, and highlights the utility of between population EHH statistics.

Patterns of cis regulatory variation in diverse human populations.

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Barbara E Stranger

Full Text Available The genetic basis of gene expression variation has long been studied with the aim to understand the landscape of regulatory variants, but also more recently to assist in the interpretation and elucidation of disease signals. To date, many studies have looked in specific tissues and population-based samples, but there has been limited assessment of the degree of inter-population variability in regulatory variation. We analyzed genome-wide gene expression in lymphoblastoid cell lines from a total of 726 individuals from 8 global populations from the HapMap3 project and correlated gene expression levels with HapMap3 SNPs located in cis to the genes. We describe the influence of ancestry on gene expression levels within and between these diverse human populations and uncover a non-negligible impact on global patterns of gene expression. We further dissect the specific functional pathways differentiated between populations. We also identify 5,691 expression quantitative trait loci (eQTLs after controlling for both non-genetic factors and population admixture and observe that half of the cis-eQTLs are replicated in one or more of the populations. We highlight patterns of eQTL-sharing between populations, which are partially determined by population genetic relatedness, and discover significant sharing of eQTL effects between Asians, European-admixed, and African subpopulations. Specifically, we observe that both the effect size and the direction of effect for eQTLs are highly conserved across populations. We observe an increasing proximity of eQTLs toward the transcription start site as sharing of eQTLs among populations increases, highlighting that variants close to TSS have stronger effects and therefore are more likely to be detected across a wider panel of populations. Together these results offer a unique picture and resource of the degree of differentiation among human populations in functional regulatory variation and provide an estimate for

Global human capital: integrating education and population.

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Lutz, Wolfgang; KC, Samir

2011-07-29

Almost universally, women with higher levels of education have fewer children. Better education is associated with lower mortality, better health, and different migration patterns. Hence, the global population outlook depends greatly on further progress in education, particularly of young women. By 2050, the highest and lowest education scenarios--assuming identical education-specific fertility rates--result in world population sizes of 8.9 and 10.0 billion, respectively. Better education also matters for human development, including health, economic growth, and democracy. Existing methods of multi-state demography can quantitatively integrate education into standard demographic analysis, thus adding the "quality" dimension.

Neutral Theory: From Complex Population History to Natural Selection and Sociocultural Phenomena in Human Populations.

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Austerlitz, Frédéric; Heyer, Evelyne

2018-06-01

Here, we present a synthetic view on how Kimura's Neutral theory has helped us gaining insight on the different evolutionary forces that shape human evolution. We put this perspective in the frame of recent emerging challenges: the use of whole genome data for reconstructing population histories, natural selection on complex polygenic traits, and integrating cultural processes in human evolution.

Climate variability, human wildlife conflict and population dynamics of lions Panthera leo

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Trinkel, Martina

2013-04-01

Large carnivores are threatened by habitat loss, declining prey populations and direct persecution. Pride dynamics of eight lion prides in the centre of the Etosha National Park, Namibia are described during a 16-year study. Since the beginning of the 1980s, the number of adult and subadult lions declined continuously to two third of its initial population size, and reached a new equilibrium in the 1990s. Pride sizes decreased from 6.3 adult females in 1989 to 2.8 lionesses in 1997. While the number of adult females declined continuously, the number of adult males, subadult females and subadult males remained constant over the years. A severe drought period, lasting for more than 20 years, led to declining prey populations inside the lions' territory. Besides declining prey populations, conflict with humans at the border of Etosha puts substantial pressure onto the lion population: 82 % of all known lion mortalities were caused by humans, and most of these consisted of adult females (28 %) and subadult males (29 %). I postulate that the considerable decline in the lion population is a response to declining prey populations, and although the human predator conflict is severe, it does not seem to limit the size of Etosha's lion population.

[Elderly human being with ostomy and environments of care: reflection on the perspective of complexity].

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Barros, Edaiane Joana Lima; Santos, Silvana Sidney Costa; Lunardi, Valéria Lerch; Lunardi Filho, Wilson Danilo

2012-01-01

This is discussion about the relationship between elderly human beings with ostomy and their environments care, under the perspective of Complexity Edgar Morin. An axis holds the reflection: environments of care for elderly humans with ostomy. In this sense, we present three types of environment that surround the context of elderly humans with ostomy: home environment, group environment and hospital environment. This brings, as a social contribution, a new look about resizing caring of elderly humans with ostomy in their environment. It is considered that the environment hosting this human being contains a diversity of feelings, emotions, experiences; it binds multiple meanings, from the Complexity perspective, about the relationship between the environment and the caring process.

Human population growth offsets climate-driven increase in woody vegetation in sub-Saharan Africa.

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Brandt, Martin; Rasmussen, Kjeld; Peñuelas, Josep; Tian, Feng; Schurgers, Guy; Verger, Aleixandre; Mertz, Ole; Palmer, John R B; Fensholt, Rasmus

2017-03-06

The rapidly growing human population in sub-Saharan Africa generates increasing demand for agricultural land and forest products, which presumably leads to deforestation. Conversely, a greening of African drylands has been reported, but this has been difficult to associate with changes in woody vegetation. There is thus an incomplete understanding of how woody vegetation responds to socio-economic and environmental change. Here we used a passive microwave Earth observation data set to document two different trends in land area with woody cover for 1992-2011: 36% of the land area (6,870,000 km 2 ) had an increase in woody cover largely in drylands, and 11% had a decrease (2,150,000 km 2 ), mostly in humid zones. Increases in woody cover were associated with low population growth, and were driven by increases in CO 2 in the humid zones and by increases in precipitation in drylands, whereas decreases in woody cover were associated with high population growth. The spatially distinct pattern of these opposing trends reflects, first, the natural response of vegetation to precipitation and atmospheric CO 2 , and second, deforestation in humid areas, minor in size but important for ecosystem services, such as biodiversity and carbon stocks. This nuanced picture of changes in woody cover challenges widely held views of a general and ongoing reduction of the woody vegetation in Africa.

Genetic Diversity and Distribution of Blastocystis Subtype 3 in Human Populations, with Special Reference to a Rural Population in Central Mexico

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Liliana Rojas-Velázquez

2018-01-01

Full Text Available Blastocystis subtype 3 (ST3 is a parasitic protist found in the digestive tract of symptomatic and asymptomatic humans around the world. While this parasite exhibits a high prevalence in the human population, its true geographic distribution and global genetic diversity are still unknown. This gap in knowledge limits the understanding of the spread mechanisms, epidemiology, and impact that this parasite has on human populations. Herein, we provided new data on the geographical distribution and genetic diversity of Blastocystis ST3 from a rural human population in Mexico. To do so, we collected and targeted the SSU-rDNA region in fecal samples from this population and further compared its genetic diversity and structure with that previously observed in populations of Blastocystis ST3 from other regions of the planet. Our analyses reveled that diversity of Blastocystis ST3 showed a high haplotype diversity and genetic structure to the world level; however, they were low in the Morelos population. The haplotype network revealed a common widespread haplotype from which the others were generated recently. Finally, our results suggested a recent expansion of the diversity of Blastocystis ST3 worldwide.

Evaluation of retro-reflective coating performance by reflectance and perceived relative brightness measurements

International Nuclear Information System (INIS)

Luse, Kaiva; Pausus, Anete; Karitans, Varis; Ozolins, Maris; Tukisa, Madara

2011-01-01

Retro-reflective properties of six types and five different colors or retro-reflective materials were discussed in this paper. Reflectance optical indicatrix of samples was determined and compared to obtained psychophyisical data of perceived brightness of human observer. Microscopic structure of the retro-reflective active regions of RR's was studied. Statistically significant differences in reflectivity and brightness of various types and colors of RR's were found.

Some reflections on human needs, peace, transculturality and Igbo proverbs in the light of Emmanuel Edeh's African philosophy.

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Prstačić, Miroslav

2015-03-01

Within the framework of a transcultural, psychodynamic and holistic approach, Edeh's concept of Man as Mma-di (in Igbo language in Nigeria, mma-di = good that is, and mma-ndu = the beauty of Life) is presented as the nucleus of his philosophical articulation from an African metaphysical-anthropological perspective. In this context, some reflections are shown on the following topics: human creativity and peace... of mind, body and soul, as existential values and entity in bioethics; aspects of Edeh's philosophy and his work on the peace in the world; transculturality and Igbo proverbs shaped in form of Japanese Haiku poetry. These reflections emphasize the importance of induced aesthetic mental state in the subject, which derives from biological impulses but from archetypal and symbolic value of the object and continuously enter into a metaphysical experience as a form of life energy and human existential need. In this context, we discover also Edeh's philosophy as a new stimulus for further reflections and research on human life potentials, creativity, peace and Man's cosmic responsibility.

Harvesting the weak angular reflections from the fundus of the human eye : on measuring and analyzing the light wasted by the retina

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Kraats, J. van der

2007-01-01

Summary of the thesis “Harvesting the weak angular reflections from the fundus of the human eye” by Jan van de Kraats University Medical Centre Utrecht. Defended October 16, 2007. This thesis is on the modeling of the optical reflection of the human fovea, and on the three instruments build for

Evolutionary forces shaping genomic islands of population differentiation in humans

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Hofer Tamara

2012-03-01

Full Text Available Abstract Background Levels of differentiation among populations depend both on demographic and selective factors: genetic drift and local adaptation increase population differentiation, which is eroded by gene flow and balancing selection. We describe here the genomic distribution and the properties of genomic regions with unusually high and low levels of population differentiation in humans to assess the influence of selective and neutral processes on human genetic structure. Methods Individual SNPs of the Human Genome Diversity Panel (HGDP showing significantly high or low levels of population differentiation were detected under a hierarchical-island model (HIM. A Hidden Markov Model allowed us to detect genomic regions or islands of high or low population differentiation. Results Under the HIM, only 1.5% of all SNPs are significant at the 1% level, but their genomic spatial distribution is significantly non-random. We find evidence that local adaptation shaped high-differentiation islands, as they are enriched for non-synonymous SNPs and overlap with previously identified candidate regions for positive selection. Moreover there is a negative relationship between the size of islands and recombination rate, which is stronger for islands overlapping with genes. Gene ontology analysis supports the role of diet as a major selective pressure in those highly differentiated islands. Low-differentiation islands are also enriched for non-synonymous SNPs, and contain an overly high proportion of genes belonging to the 'Oncogenesis' biological process. Conclusions Even though selection seems to be acting in shaping islands of high population differentiation, neutral demographic processes might have promoted the appearance of some genomic islands since i as much as 20% of islands are in non-genic regions ii these non-genic islands are on average two times shorter than genic islands, suggesting a more rapid erosion by recombination, and iii most loci are

Human Population Influence on the Planet

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Pimentel, D.

2004-12-01

The continued expansion of the human population, now at 6.3 billion projected to reach 12 billion by 2050, is using, destroying, and polluting the very Earth's resources that support human life. Currently the World Health Organization reports that more than 3 billion people are malnourished - largest number ever. Contributing to the malnourishment problem is soil erosion that results in the loss of about 75 billion tons of soil from agriculture each year. More than 99% of all food for the world comes from the land - less than 1% from the oceans and other aquatic ecosystems. Yet agricultural cropland is being abandoned because of soil erosion and salinization and the rapid spread of human settlements. Water is essential for all life and agriculture is the major consumer accounting for more than 70% of freshwater used. Already water shortages are critical in the U.S. and worldwide. Thus far, abundant fossil fuels are supporting the expansion of agricultural productivity as well as industry and transport growth. Yet credible evidence suggests that the supplies of oil and natural gas especially are rapidly diminishing. The development of renewable energy is behind schedule and when developed will only supply only about half of current energy used. If we do not work towards a relative balance between human numbers and essential natural resources, humans will suffer. Human health, productivity and well being, now and for future generations, require the continued availability of our basic resources - soil, water, foods, and energy.

Reflections on Asia: Borrowing Lessons from the Humanities in Social Science Coursework

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Howard Sanborn

2017-07-01

Full Text Available What lessons can political science classes borrow from the humanities? This paper presents the results of a multi-year study on teaching about Asia as part of a general education program. Given the challenges of meeting common learning outcomes while also teaching discipline-specific lessons, political science courses often underperformed in assessments when compared to benchmark expectations. While our initial conclusion—that a greater focus on multimodal assignments would promote deeper learning and reflection—proved unfounded, explicitly emphasizing students’ reflection on their own process of democratic engagement, in comparison to that of their counterparts in Asia, did seem to address the shortcomings of the previous approaches by giving students context and guidance in their understanding of how democracy works at home and abroad. Data from reflective essays, collected over two years, provide evidence for this finding.

Biological effects of alpha radiation on a human population

International Nuclear Information System (INIS)

Thorleifson, E.M.; Marro, L.; Tracy, B.L.; Wilkinson, D.; Segura, T.M.; Prud'homme-Lalonde, L.; Leach, K.; Ford, B.N.

2003-01-01

Full text: In the environment, natural and man-made sources of radioactive material can become integrated into the food chain. Polonium-210 is a significant source of radiation exposure to caribou and to northern human populations who are dependent on caribou for a major portion of their meat supply. Previous work has shown that humans consuming caribou meat containing measurable quantities of polonium-210 can incorporate a substantial fraction of the radionuclide (Thomas et. al.). Conventional chromosome aberration analysis of blood samples collected from 40 individuals who routinely consumed caribou meat was performed to measure genetic damage from the ingested radioactive material. At least 500 metaphase spreads were analysed for each of 39 individuals. Radiation-specific chromosomal aberrations such as dicentrics and rings were scored and their frequencies were compared to the range of aberrations observed in non-caribou consuming populations. This study was designed to address the possible impact of environmental polonium-210 on background radiation health effects in humans

Metabolic heat production by human and animal populations in cities

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Stewart, Iain D.; Kennedy, Chris A.

2017-07-01

Anthropogenic heating from building energy use, vehicle fuel consumption, and human metabolism is a key term in the urban energy budget equation. Heating from human metabolism, however, is often excluded from urban energy budgets because it is widely observed to be negligible. Few reports for low-latitude cities are available to support this observation, and no reports exist on the contribution of domestic animals to urban heat budgets. To provide a more comprehensive view of metabolic heating in cities, we quantified all terms of the anthropogenic heat budget at metropolitan scale for the world's 26 largest cities, using a top-down statistical approach. Results show that metabolic heat release from human populations in mid-latitude cities (e.g. London, Tokyo, New York) accounts for 4-8% of annual anthropogenic heating, compared to 10-45% in high-density tropical cities (e.g. Cairo, Dhaka, Kolkata). Heat release from animal populations amounts to <1% of anthropogenic heating in all cities. Heat flux density from human and animal metabolism combined is highest in Mumbai—the world's most densely populated megacity—at 6.5 W m-2, surpassing heat production by electricity use in buildings (5.8 W m-2) and fuel combustion in vehicles (3.9 W m-2). These findings, along with recent output from global climate models, suggest that in the world's largest and most crowded cities, heat emissions from human metabolism alone can force measurable change in mean annual temperature at regional scale.

Metabolic heat production by human and animal populations in cities.

Science.gov (United States)

Stewart, Iain D; Kennedy, Chris A

2017-07-01

Anthropogenic heating from building energy use, vehicle fuel consumption, and human metabolism is a key term in the urban energy budget equation. Heating from human metabolism, however, is often excluded from urban energy budgets because it is widely observed to be negligible. Few reports for low-latitude cities are available to support this observation, and no reports exist on the contribution of domestic animals to urban heat budgets. To provide a more comprehensive view of metabolic heating in cities, we quantified all terms of the anthropogenic heat budget at metropolitan scale for the world's 26 largest cities, using a top-down statistical approach. Results show that metabolic heat release from human populations in mid-latitude cities (e.g. London, Tokyo, New York) accounts for 4-8% of annual anthropogenic heating, compared to 10-45% in high-density tropical cities (e.g. Cairo, Dhaka, Kolkata). Heat release from animal populations amounts to heating in all cities. Heat flux density from human and animal metabolism combined is highest in Mumbai-the world's most densely populated megacity-at 6.5 W m -2 , surpassing heat production by electricity use in buildings (5.8 W m -2 ) and fuel combustion in vehicles (3.9 W m -2 ). These findings, along with recent output from global climate models, suggest that in the world's largest and most crowded cities, heat emissions from human metabolism alone can force measurable change in mean annual temperature at regional scale.

Evaluation of retro-reflective coating performance by reflectance and perceived relative brightness measurements

Energy Technology Data Exchange (ETDEWEB)

Luse, Kaiva; Pausus, Anete; Karitans, Varis; Ozolins, Maris; Tukisa, Madara, E-mail: kaiva.luse@gmail.com [University of Latvia, Optometry and Vision Science Department, Kengaraga street 8, Riga LV-1063 (Latvia)

2011-06-23

Retro-reflective properties of six types and five different colors or retro-reflective materials were discussed in this paper. Reflectance optical indicatrix of samples was determined and compared to obtained psychophyisical data of perceived brightness of human observer. Microscopic structure of the retro-reflective active regions of RR's was studied. Statistically significant differences in reflectivity and brightness of various types and colors of RR's were found.

Demographics of an ornate box turtle population experiencing minimal human-induced disturbances

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Converse, S.J.; Iverson, J.B.; Savidge, J.A.

2005-01-01

Human-induced disturbances may threaten the viability of many turtle populations, including populations of North American box turtles. Evaluation of the potential impacts of these disturbances can be aided by long-term studies of populations subject to minimal human activity. In such a population of ornate box turtles (Terrapene ornata ornata) in western Nebraska, we examined survival rates and population growth rates from 1981-2000 based on mark-recapture data. The average annual apparent survival rate of adult males was 0.883 (SE = 0.021) and of adult females was 0.932 (SE = 0.014). Minimum winter temperature was the best of five climate variables as a predictor of adult survival. Survival rates were highest in years with low minimum winter temperatures, suggesting that global warming may result in declining survival. We estimated an average adult population growth rate (????) of 1.006 (SE = 0.065), with an estimated temporal process variance (????2) of 0.029 (95% CI = 0.005-0.176). Stochastic simulations suggest that this mean and temporal process variance would result in a 58% probability of a population decrease over a 20-year period. This research provides evidence that, unless unknown density-dependent mechanisms are operating in the adult age class, significant human disturbances, such as commercial harvest or turtle mortality on roads, represent a potential risk to box turtle populations. ?? 2005 by the Ecological Society of America.

Ethical review of research on human subjects at Unilever: reflections on governance.

Science.gov (United States)

Sheehan, Mark; Marti, Vernon; Roberts, Tony

2014-07-01

This article considers the process of ethical review of research on human subjects at a very large multinational consumer products company. The commercial context of this research throws up unique challenges and opportunities that make the ethics of the process of oversight distinct from mainstream medical research. Reflection on the justification of governance processes sheds important, contrasting light on the ethics of governance of other forms and context of research. © 2013 John Wiley & Sons Ltd.

Integrating population dynamics into mapping human exposure to seismic hazard

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S. Freire

2012-11-01

Full Text Available Disaster risk is not fully characterized without taking into account vulnerability and population exposure. Assessment of earthquake risk in urban areas would benefit from considering the variation of population distribution at more detailed spatial and temporal scales, and from a more explicit integration of this improved demographic data with existing seismic hazard maps. In the present work, "intelligent" dasymetric mapping is used to model population dynamics at high spatial resolution in order to benefit the analysis of spatio-temporal exposure to earthquake hazard in a metropolitan area. These night- and daytime-specific population densities are then classified and combined with seismic intensity levels to derive new spatially-explicit four-class-composite maps of human exposure. The presented approach enables a more thorough assessment of population exposure to earthquake hazard. Results show that there are significantly more people potentially at risk in the daytime period, demonstrating the shifting nature of population exposure in the daily cycle and the need to move beyond conventional residence-based demographic data sources to improve risk analyses. The proposed fine-scale maps of human exposure to seismic intensity are mainly aimed at benefiting visualization and communication of earthquake risk, but can be valuable in all phases of the disaster management process where knowledge of population densities is relevant for decision-making.

Real-time estimation of small-area populations with human biomarkers in sewage

International Nuclear Information System (INIS)

Daughton, Christian G.

2012-01-01

A new approach is conceptualized for measuring small-area human populations by using biomarkers in sewage. The basis for the concept (SCIM: Sewage Chemical-Information Mining) is supported by a comprehensive examination and synthesis of data published across several disciplines, including medicine, microbiology, clinical chemistry, and environmental science. Accurate measures of human populations are fundamental to numerous disciplines, including economics, marketing, politics, sociology, public health and safety (e.g., disease management; assessment of natural hazards; disaster prevention and response), quality of life, and the environment. Knowing the size, distribution, and flow of a small-area (local) population facilitates understanding the numerous and complex linkages and interactions between humans and the environment. Examples include material-flow (substance-flow) analysis, determining the magnitude of per capita contribution of pollutant loadings to watersheds, or forecasting future impacts of local populations on the environment or a population's demands on resources. While no definitive approach exists for measuring small-area populations, census-taking is a long-established convention. No approach exists, however, for gauging small-area populations in real-time, as none is able to capture population dynamics, which involve transient changes (e.g., daily influx and efflux) and lasting changes (e.g., births, deaths, change in residence). Accurate measurement of small-area populations in real time has never been possible but is essential for facilitating the design of more sustainable communities. Real-time measurement would provide communities the capability of testing what-if scenarios in design and policy decisions. After evaluation of a range of biomarkers (including the nitrogenous waste product creatinine, which has been long used in clinical chemistry as a parameter to normalize the concentrations of other urinary excretion products to account for

EMPIRICAL REFLECTIONS ON MIGRATION PHENOMENON. MAJOR EFFECTS OF MIGRATION ON THE HUMAN CAPITAL

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Simona BUTA

2013-12-01

Full Text Available The paper Empirical reflections on migration phenomenon. Major effects of migration on the human capital analyzes the migration flows of the workforce (as part of the human capital globally/regionally, especially the highly qualified workforce migration. The qualified manpower processes of attracting on the work market have not been always well understood and, in some cases, have generated a series of difficulties. This is the reason why we will focus on the „waste of brains” phenomenon, which appears when highly qualified individuals are neither employed in the source-country nor in the target country; and, if they are, their job is below their qualifications.

The Impact of Evolutionary Driving Forces on Human Complex Diseases: A Population Genetics Approach

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Amr T. M. Saeb

2016-01-01

Full Text Available Investigating the molecular evolution of human genome has paved the way to understand genetic adaptation of humans to the environmental changes and corresponding complex diseases. In this review, we discussed the historical origin of genetic diversity among human populations, the evolutionary driving forces that can affect genetic diversity among populations, and the effects of human movement into new environments and gene flow on population genetic diversity. Furthermore, we presented the role of natural selection on genetic diversity and complex diseases. Then we reviewed the disadvantageous consequences of historical selection events in modern time and their relation to the development of complex diseases. In addition, we discussed the effect of consanguinity on the incidence of complex diseases in human populations. Finally, we presented the latest information about the role of ancient genes acquired from interbreeding with ancient hominids in the development of complex diseases.

Incorporating Human Interindividual Biotransformation Variance in Health Risk Assessment

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The protection of sensitive individuals within a population dictates that measures other than central tendencies be employed to estimate risk. The refinement of human health risk assessments for chemicals metabolized by the liver to reflect data on human variability can be accom...

Risk factors for human-directed canine aggression in a referral level clinical population.

Science.gov (United States)

Lord, M; Casey, R A; Loftus, B A; Blackwell, E J

2017-07-07

Risk factors for human-directed aggression were investigated using retrospective analysis of data from a referral-level clinical behaviour population in the UK. A sample of 200 cases involving human-directed canine aggression and 200 control cases involving no instance of human-directed aggression were selected at random from a population of 746 cases. The final model suggested that clinical cases with human-directed aggression were significantly younger than those presenting with other undesired behaviours (P=0.008) and that male dogs were 1.4 times more likely to be aggressive towards human beings than female dogs (P=0.019). Dogs were 1.7 times more likely to be aggressive towards people if they had attended more than five puppy classes than if they had never attended puppy class (P=0.015) and that dogs were 2.8 times more likely to be aggressive towards human beings if there was another dog between 0 months and 24 months of age in the home (P=0.004). These factors only account for 7 per cent to 10 per cent of the variance between the human-directed aggression population and the control population, but factors such as attendance at puppy classes and numbers of dogs in the household suggest the need for longitudinal studies to investigate temporal relationships.

Human Population Problems

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Emmel, Thomas C.; Sligh, Michael M.

1970-01-01

Asserts that overpopulation is the most pressing world problem. Topics discussed include population control in primitive societies, population growth and control in modern societies, methods of motivational population control, consequences of no population control, and mass famines during the 1970's in underdeveloped countries. Cities 33…

Near-peer role modeling: Can fourth-year medical students, recognized for their humanism, enhance reflection among second-year students in a physical diagnosis course?

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Mimi McEvoy

2016-09-01

Full Text Available Introduction: Humanism is cultivated through reflection and self-awareness. We aimed to employ fourth-year medical students, recognized for their humanism, to facilitate reflective sessions for second-year medical students with the intention of positively influencing reflective process toward humanistic development. Methods/Analysis: A total of 186 students were randomly assigned to one of three comparison arms: eight groups of eight students (64 students were facilitated by a fourth-year student who was a Gold Humanism Honor Society member (GHHS; eight groups (64 students by a volunteer non-GHHS student; and seven groups (58 students were non-facilitated. Before sessions, second-year students set learning goals concerning interactions with patients; fourth-year students received training materials on facilitation. Groups met twice during their 10 clinical site visits. At the last session, students completed a reflective assignment on their goal progress. Comparative mixed method analyses were conducted among the three comparison arms on reflection (reflective score on in-session assignment and session satisfaction (survey in addition to a thematic analysis of responses on the in-session assignment. Results: We found significant differences among all three comparison arms on students’ reflective scores (p=0.0003 and satisfaction (p=0.0001. T-tests comparing GHHS- and non-GHHS-facilitated groups showed significantly higher mean reflective scores for GHHS-facilitated groups (p=0.033; there were no differences on session satisfaction. Thematic analysis of students’ reflections showed attempts at self-examination, but lacked depth in addressing emotions. There was a common focus on achieving comfort and confidence in clinical skills performance. Discussion/Conclusions: Near peers, recognized for their humanism, demonstrated significant influence in deepening medical students’ reflections surrounding patient interactions or humanistic

Individuality as expression of human emancipation. Reflection on the conception of Jan Szczepański

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Tomasz Leszniewski

2017-01-01

Full Text Available The paper raises the issue of “the individual factor” in the sociological reflection on social reality. Referring to Jan Szczepański's concept of individuality it analyzes the problem of human nature and the inner world as a source of resistance to the negative consequences of collective mechanisms. The paper presents the thesis that individuality is the culmination of the process of human development. However, in the context of socio-cultural category of individuality, it is an attempt to transcend the current data and the tension between individual- ism and collectivism. Human Individuality is a potential criticism regarding the public order and social change.

Real-time estimation of small-area populations with human biomarkers in sewage

Energy Technology Data Exchange (ETDEWEB)

Daughton, Christian G., E-mail: daughton.christian@epa.gov

2012-01-01

A new approach is conceptualized for measuring small-area human populations by using biomarkers in sewage. The basis for the concept (SCIM: Sewage Chemical-Information Mining) is supported by a comprehensive examination and synthesis of data published across several disciplines, including medicine, microbiology, clinical chemistry, and environmental science. Accurate measures of human populations are fundamental to numerous disciplines, including economics, marketing, politics, sociology, public health and safety (e.g., disease management; assessment of natural hazards; disaster prevention and response), quality of life, and the environment. Knowing the size, distribution, and flow of a small-area (local) population facilitates understanding the numerous and complex linkages and interactions between humans and the environment. Examples include material-flow (substance-flow) analysis, determining the magnitude of per capita contribution of pollutant loadings to watersheds, or forecasting future impacts of local populations on the environment or a population's demands on resources. While no definitive approach exists for measuring small-area populations, census-taking is a long-established convention. No approach exists, however, for gauging small-area populations in real-time, as none is able to capture population dynamics, which involve transient changes (e.g., daily influx and efflux) and lasting changes (e.g., births, deaths, change in residence). Accurate measurement of small-area populations in real time has never been possible but is essential for facilitating the design of more sustainable communities. Real-time measurement would provide communities the capability of testing what-if scenarios in design and policy decisions. After evaluation of a range of biomarkers (including the nitrogenous waste product creatinine, which has been long used in clinical chemistry as a parameter to normalize the concentrations of other urinary excretion products to

Genetic affinity among five different population groups in India reflecting a Y-chromosome gene flow.

Science.gov (United States)

Saha, Anjana; Sharma, Swarkar; Bhat, Audesh; Pandit, Awadesh; Bamezai, Ramesh

2005-01-01

Four binary polymorphisms and four multiallelic short tandem repeat (STR) loci from the nonrecombining region of the human Y-chromosome were typed in different Indian population groups from Uttar Pradeh (UP), Bihar (BI), Punjab (PUNJ), and Bengal (WB) speaking the Indo-Aryan dialects and from South India (SI) with the root in the Dravidian language. We identified four major haplogroups [(P) 1+, (C and F) 2+, (R1a) 3, (K) 26+] and 114 combinations of Y-STR haplotypes. Analyses of the haplogroups indicated no single origin from any lineage but a result of a conglomeration of different lineages from time to time. The phylogenetic analyses indicate a high degree of population admixture and a greater genetic proximity for the studied population groups when compared with other world populations.

The cultural evolution of human communication systems in different sized populations: usability trumps learnability.

Science.gov (United States)

Fay, Nicolas; Ellison, T Mark

2013-01-01

This study examines the intergenerational transfer of human communication systems. It tests if human communication systems evolve to be easy to learn or easy to use (or both), and how population size affects learnability and usability. Using an experimental-semiotic task, we find that human communication systems evolve to be easier to use (production efficiency and reproduction fidelity), but harder to learn (identification accuracy) for a second generation of naïve participants. Thus, usability trumps learnability. In addition, the communication systems that evolve in larger populations exhibit distinct advantages over those that evolve in smaller populations: the learnability loss (from the Initial signs) is more muted and the usability benefits are more pronounced. The usability benefits for human communication systems that evolve in a small and large population is explained through guided variation reducing sign complexity. The enhanced performance of the communication systems that evolve in larger populations is explained by the operation of a content bias acting on the larger pool of competing signs. The content bias selects for information-efficient iconic signs that aid learnability and enhance usability.

Near-Infrared Confocal Laser Reflectance Cytoarchitectural Imaging of the Substantia Nigra and Cerebellum in the Fresh Human Cadaver.

Science.gov (United States)

Cheyuo, Cletus; Grand, Walter; Balos, Lucia L

2017-01-01

Cytoarchitectural neuroimaging remains critical for diagnosis of many brain diseases. Fluorescent dye-enhanced, near-infrared confocal in situ cellular imaging of the brain has been reported. However, impermeability of the blood-brain barrier to most fluorescent dyes limits clinical utility of this modality. The differential degree of reflectance from brain tissue with unenhanced near-infrared imaging may represent an alternative technique for in situ cytoarchitectural neuroimaging. We assessed the utility of unenhanced near-infrared confocal laser reflectance imaging of the cytoarchitecture of the cerebellum and substantia nigra in 2 fresh human cadaver brains using a confocal near-infrared laser probe. Cellular images based on near-infrared differential reflectance were captured at depths of 20-180 μm from the brain surface. Parts of the cerebellum and substantia nigra imaged using the probe were subsequently excised and stained with hematoxylin and eosin for histologic correlation. Near-infrared reflectance imaging revealed the 3-layered cytoarchitecture of the cerebellum, with Purkinje cells appearing hyperreflectant. In the substantia nigra, neurons appeared hyporeflectant with hyperreflectant neuromelanin cytoplasmic inclusions. Cytoarchitecture of the cerebellum and substantia nigra revealed on near-infrared imaging closely correlated with the histology on hematoxylin-eosin staining. We showed that unenhanced near-infrared reflectance imaging of fresh human cadaver brain can reliably identify and distinguish neurons and detailed cytoarchitecture of the cerebellum and substantia nigra. Copyright © 2016 Elsevier Inc. All rights reserved.

Reflections of the social environment in chimpanzee memory: applying rational analysis beyond humans.

Science.gov (United States)

Stevens, Jeffrey R; Marewski, Julian N; Schooler, Lael J; Gilby, Ian C

2016-08-01

In cognitive science, the rational analysis framework allows modelling of how physical and social environments impose information-processing demands onto cognitive systems. In humans, for example, past social contact among individuals predicts their future contact with linear and power functions. These features of the human environment constrain the optimal way to remember information and probably shape how memory records are retained and retrieved. We offer a primer on how biologists can apply rational analysis to study animal behaviour. Using chimpanzees ( Pan troglodytes ) as a case study, we modelled 19 years of observational data on their social contact patterns. Much like humans, the frequency of past encounters in chimpanzees linearly predicted future encounters, and the recency of past encounters predicted future encounters with a power function. Consistent with the rational analyses carried out for human memory, these findings suggest that chimpanzee memory performance should reflect those environmental regularities. In re-analysing existing chimpanzee memory data, we found that chimpanzee memory patterns mirrored their social contact patterns. Our findings hint that human and chimpanzee memory systems may have evolved to solve similar information-processing problems. Overall, rational analysis offers novel theoretical and methodological avenues for the comparative study of cognition.

Improved physiologically based pharmacokinetic model for oral exposures to chromium in mice, rats, and humans to address temporal variation and sensitive populations

Energy Technology Data Exchange (ETDEWEB)

Kirman, C.R., E-mail: ckirman@summittoxicology.com [Summit Toxicology, PO Box 3209, Bozeman, MT 59715 (United States); Suh, M.; Proctor, D.M. [ToxStrategies, Mission Viejo, CA (United States); Hays, S.M. [Summit Toxicology, PO Box 3209, Bozeman, MT 59715 (United States)

2017-06-15

A physiologically based pharmacokinetic (PBPK) model for hexavalent chromium [Cr(VI)] in mice, rats, and humans developed previously (Kirman et al., 2012, 2013), was updated to reflect an improved understanding of the toxicokinetics of the gastrointestinal tract following oral exposures. Improvements were made to: (1) the reduction model, which describes the pH-dependent reduction of Cr(VI) to Cr(III) in the gastrointestinal tract under both fasted and fed states; (2) drinking water pattern simulations, to better describe dosimetry in rodents under the conditions of the NTP cancer bioassay; and (3) parameterize the model to characterize potentially sensitive human populations. Important species differences, sources of non-linear toxicokinetics, and human variation are identified and discussed within the context of human health risk assessment. - Highlights: • An improved version of the PBPK model for Cr(VI) toxicokinetics was developed. • The model incorporates data collected to fill important data gaps. • Model predictions for specific age groups and sensitive subpopulations are provided. • Implications to human health risk assessment are discussed.

Faster Increases in Human Life Expectancy Could Lead to Slower Population Aging

Science.gov (United States)

2015-01-01

Counterintuitively, faster increases in human life expectancy could lead to slower population aging. The conventional view that faster increases in human life expectancy would lead to faster population aging is based on the assumption that people become old at a fixed chronological age. A preferable alternative is to base measures of aging on people’s time left to death, because this is more closely related to the characteristics that are associated with old age. Using this alternative interpretation, we show that faster increases in life expectancy would lead to slower population aging. Among other things, this finding affects the assessment of the speed at which countries will age. PMID:25876033

Diversity of human small intestinal Streptococcus and Veillonella populations

NARCIS (Netherlands)

van den Bogert, Bartholomeus; Erkus, Oylum; Boekhorst, Jos; de Goffau, Marcus; Smid, Eddy J.; Zoetendal, Erwin G.; Kleerebezem, Michiel

Molecular and cultivation approaches were employed to study the phylogenetic richness and temporal dynamics of Streptococcus and Veillonella populations in the small intestine. Microbial profiling of human small intestinal samples collected from four ileostomy subjects at four time points displayed

Conservation genetics of managed ungulate populations

Science.gov (United States)

Scribner, Kim T.

1993-01-01

Natural populations of many species are increasingly impacted by human activities. Perturbations are particularly pronunced for large ungulates due in part to sport and commercial harvest, to reductions and fragmentation of native habitat, and as the result of reintroductions. These perturbations affect population size, sex and age composition, and population breeding structure, and as a consequence affect the levels and partitioning of genetic variation. Three case histories highlighting long-term ecological genetic research on mule deer Odocoileus hemionus (Rafinesque, 1817), white-tailed deer O. virginianus (Zimmermann, 1780), and Alpine ibex Capra i. ibex Linnaeus, 1758 are presented. Joint examinations of population ecological and genetic data from several populations of each species reveal: (1) that populations are not in genetic equilibrium, but that allele frequencies and heterozygosity change dramatically over time and among cohorts produced in successive years, (2) populations are genetically structured over short and large geographic distances reflecting local breeding structure and patterns of gene flow, respectively; however, this structure is quite dynamic over time, due in part to population exploitation, and (3) restocking programs are often undertaken with small numbers of founding individuals resulting in dramatic declines in levels of genetic variability and increasing levels of genetic differentiation among populations due to genetic drift. Genetic characteristics have and will continue to provide valuable indirect sources of information relating enviromental and human perturbations to changes in population processes.

Anthropogenics: Human influence on global and genetic homogenization of parasite populations

Science.gov (United States)

The distribution, abundance, and diversity of life on Earth have been greatly shaped by human activities. This is no truer than in the geographic expansion of parasites; however, measuring the extent to which humans have influenced the dissemination and population structure of parasites has been cha...

A mathematical model of interaction among humans, vampires and werewolves populations

Science.gov (United States)

Sumarti, Novriana; Nurrizky, Insan; Nuraini, Nuning

2018-03-01

In every country there are many fictional creatures depicting evil. In the western world, fictional creatures who often appear in horror stories are vampires and werewolves. Many released movies expose the conflict between humans with one or both creatures. In this paper, the interaction among humans, vampires and werewolves is modeled using a system of differential equations. We consider the stability of equilibrium points of the system that represent four situations; only humans remain or a disease-free condition, either vampires or werewolves are going to extinction, and no population goes extinct. The derived model is implemented for depicting some scenarios in the movie series of Underworld. The model can describe the fluctuation of vampires and werewolves population from the beginning to their extinction at 1500 years since the story started.

The cultural evolution of human communication systems in different sized populations: usability trumps learnability.

Directory of Open Access Journals (Sweden)

Nicolas Fay

Full Text Available This study examines the intergenerational transfer of human communication systems. It tests if human communication systems evolve to be easy to learn or easy to use (or both, and how population size affects learnability and usability. Using an experimental-semiotic task, we find that human communication systems evolve to be easier to use (production efficiency and reproduction fidelity, but harder to learn (identification accuracy for a second generation of naïve participants. Thus, usability trumps learnability. In addition, the communication systems that evolve in larger populations exhibit distinct advantages over those that evolve in smaller populations: the learnability loss (from the Initial signs is more muted and the usability benefits are more pronounced. The usability benefits for human communication systems that evolve in a small and large population is explained through guided variation reducing sign complexity. The enhanced performance of the communication systems that evolve in larger populations is explained by the operation of a content bias acting on the larger pool of competing signs. The content bias selects for information-efficient iconic signs that aid learnability and enhance usability.

Population receptive field (pRF) measurements of chromatic responses in human visual cortex using fMRI.

Science.gov (United States)

Welbourne, Lauren E; Morland, Antony B; Wade, Alex R

2018-02-15

The spatial sensitivity of the human visual system depends on stimulus color: achromatic gratings can be resolved at relatively high spatial frequencies while sensitivity to isoluminant color contrast tends to be more low-pass. Models of early spatial vision often assume that the receptive field size of pattern-sensitive neurons is correlated with their spatial frequency sensitivity - larger receptive fields are typically associated with lower optimal spatial frequency. A strong prediction of this model is that neurons coding isoluminant chromatic patterns should have, on average, a larger receptive field size than neurons sensitive to achromatic patterns. Here, we test this assumption using functional magnetic resonance imaging (fMRI). We show that while spatial frequency sensitivity depends on chromaticity in the manner predicted by behavioral measurements, population receptive field (pRF) size measurements show no such dependency. At any given eccentricity, the mean pRF size for neuronal populations driven by luminance, opponent red/green and S-cone isolating contrast, are identical. Changes in pRF size (for example, an increase with eccentricity and visual area hierarchy) are also identical across the three chromatic conditions. These results suggest that fMRI measurements of receptive field size and spatial resolution can be decoupled under some circumstances - potentially reflecting a fundamental dissociation between these parameters at the level of neuronal populations. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Landscape requirements of a primate population in a human-dominated environment

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Hoffman Tali S

2012-01-01

Full Text Available Abstract Introduction As urban and rural land development become widespread features of the global landscape so an understanding of the landscape requirements of displaced and isolated wildlife species becomes increasingly important for conservation planning. In the Cape Peninsula, South Africa, rapid human population growth, and the associated urban and rural land transformation, threatens the sustainability of the local chacma baboon population. Here we analyse spatial data collected from nine of the 12 extant troops to determine their population-level landscape requirements. We use hurdle models to ascertain the key landscape features influencing baboon occurrence and abundance patterns on two hierarchical spatial scales. Results Both spatial scales produced similar results that were ecologically reliable and interpretable. The models indicated that baboons were more likely to occur, and be more abundant, at low altitudes, on steep slopes and in human-modified habitats. The combination of these landscape variables provides baboons with access to the best quality natural and anthropogenic food sources in close proximity to one another and suitable sleeping sites. Surface water did not emerge as an influential landscape feature presumably as the area is not water stressed. Conclusions The model results indicate that land development in the Cape Peninsula has pushed baboons into increasingly marginal natural habitat while simultaneously providing them with predictable and easily accessible food sources in human-modified habitats. The resultant spatial competition between humans and baboons explains the high levels of human-baboon conflict and further erosion of the remaining land fragments is predicted to exacerbate competition. This study demonstrates how the quantification of animal landscape requirements can provide a mechanism for identifying priority conservation areas at the human-wildlife interface.

The evolution of wealth transmission in human populations: a stochastic model

International Nuclear Information System (INIS)

Augustins, G; Etienne, L; Ferrer, R; Godelle, B; Rousset, F; Ferdy, J-B; Pitard, E

2014-01-01

Reproductive success and survival are influenced by wealth in human populations. Wealth is transmitted to offsprings and strategies of transmission vary over time and among populations, the main variation being how equally wealth is transmitted to children. Here we propose a model where we simulate both the dynamics of wealth in a population and the evolution of a trait that determines how wealth is transmitted from parents to offspring, in a darwinian context

Population specific biomarkers of human aging: a big data study using South Korean, Canadian and Eastern European patient populations.

Science.gov (United States)

Mamoshina, Polina; Kochetov, Kirill; Putin, Evgeny; Cortese, Franco; Aliper, Alexander; Lee, Won-Suk; Ahn, Sung-Min; Uhn, Lee; Skjodt, Neil; Kovalchuk, Olga; Scheibye-Knudsen, Morten; Zhavoronkov, Alex

2018-01-11

Accurate and physiologically meaningful biomarkers for human aging are key to assessing anti-aging therapies. Given ethnic differences in health, diet, lifestyle, behaviour, environmental exposures and even average rate of biological aging, it stands to reason that aging clocks trained on datasets obtained from specific ethnic populations are more likely to account for these potential confounding factors, resulting in an enhanced capacity to predict chronological age and quantify biological age. Here we present a deep learning-based hematological aging clock modeled using the large combined dataset of Canadian, South Korean and Eastern European population blood samples that show increased predictive accuracy in individual populations compared to population-specific hematologic aging clocks. The performance of models was also evaluated on publicly-available samples of the American population from the National Health and Nutrition Examination Survey (NHANES). In addition, we explored the association between age predicted by both population-specific and combined hematological clocks and all-cause mortality. Overall, this study suggests a) the population-specificity of aging patterns and b) hematologic clocks predicts all-cause mortality. Proposed models added to the freely available Aging.AI system allowing improved ability to assess human aging. © The Author(s) 2018. Published by Oxford University Press on behalf of The Gerontological Society of America.

Commonalities in Development of Pure Breeds and Population Isolates Revealed in the Genome of the Sardinian Fonni's Dog

Science.gov (United States)

Dreger, Dayna L.; Davis, Brian W.; Cocco, Raffaella; Sechi, Sara; Di Cerbo, Alessandro; Parker, Heidi G.; Polli, Michele; Marelli, Stefano P.; Crepaldi, Paola; Ostrander, Elaine A.

2016-01-01

The island inhabitants of Sardinia have long been a focus for studies of complex human traits due to their unique ancestral background and population isolation reflecting geographic and cultural restriction. Population isolates share decreased genomic diversity, increased linkage disequilibrium, and increased inbreeding coefficients. In many regions, dogs and humans have been exposed to the same natural and artificial forces of environment, growth, and migration. Distinct dog breeds have arisen through human-driven selection of characteristics to meet an ideal standard of appearance and function. The Fonni’s Dog, an endemic dog population on Sardinia, has not been subjected to an intensive system of artificial selection, but rather has developed alongside the human population of Sardinia, influenced by geographic isolation and unregulated selection based on its environmental adaptation and aptitude for owner-desired behaviors. Through analysis of 28 dog breeds, represented with whole-genome sequences from 13 dogs and ∼170,000 genome-wide single nucleotide variants from 155 dogs, we have produced a genomic illustration of the Fonni’s Dog. Genomic patterns confirm within-breed similarity, while population and demographic analyses provide spatial identity of Fonni’s Dog to other Mediterranean breeds. Investigation of admixture and fixation indices reveals insights into the involvement of Fonni’s Dogs in breed development throughout the Mediterranean. We describe how characteristics of population isolates are reflected in dog breeds that have undergone artificial selection, and are mirrored in the Fonni’s Dog through traditional isolating factors that affect human populations. Lastly, we show that the genetic history of Fonni’s Dog parallels demographic events in local human populations. PMID:27519604

Public health nursing, ethics and human rights.

Science.gov (United States)

Ivanov, Luba L; Oden, Tami L

2013-05-01

Public health nursing has a code of ethics that guides practice. This includes the American Nurses Association Code of Ethics for Nurses, Principles of the Ethical Practice of Public Health, and the Scope and Standards of Public Health Nursing. Human rights and Rights-based care in public health nursing practice are relatively new. They reflect human rights principles as outlined in the Universal Declaration of Human Rights and applied to public health practice. As our health care system is restructured and there are new advances in technology and genetics, a focus on providing care that is ethical and respects human rights is needed. Public health nurses can be in the forefront of providing care that reflects an ethical base and a rights-based approach to practice with populations. © 2013 Wiley Periodicals, Inc.

Reflections of the social environment in chimpanzee memory: applying rational analysis beyond humans

Science.gov (United States)

Marewski, Julian N.; Schooler, Lael J.; Gilby, Ian C.

2016-01-01

In cognitive science, the rational analysis framework allows modelling of how physical and social environments impose information-processing demands onto cognitive systems. In humans, for example, past social contact among individuals predicts their future contact with linear and power functions. These features of the human environment constrain the optimal way to remember information and probably shape how memory records are retained and retrieved. We offer a primer on how biologists can apply rational analysis to study animal behaviour. Using chimpanzees (Pan troglodytes) as a case study, we modelled 19 years of observational data on their social contact patterns. Much like humans, the frequency of past encounters in chimpanzees linearly predicted future encounters, and the recency of past encounters predicted future encounters with a power function. Consistent with the rational analyses carried out for human memory, these findings suggest that chimpanzee memory performance should reflect those environmental regularities. In re-analysing existing chimpanzee memory data, we found that chimpanzee memory patterns mirrored their social contact patterns. Our findings hint that human and chimpanzee memory systems may have evolved to solve similar information-processing problems. Overall, rational analysis offers novel theoretical and methodological avenues for the comparative study of cognition. PMID:27853606

Indigenous Health and Human Rights: A Reflection on Law and Culture

Science.gov (United States)

Mazel, Odette

2018-01-01

In Australia, Aboriginal and Torres Strait Islander peoples bear a greater burden of disease and have lower life expectancy than their non-Indigenous counterparts. These combined indicators are evidence of an entrenched health crisis in the Indigenous population that is linked to systemic disadvantage over many decades. In an effort to improve life expectancy and lessen the burden of disease, a number of strategies and national frameworks now embed a human rights-based approach to achieving health equality. This paper explores the application of human rights to Indigenous health and examines the inherent tensions that exist in engaging a system of law based on universal assumptions of the Enlightenment to advance Indigenous rights. What becomes apparent through this exploration is that the strategic approach of Indigenous peoples’ use of human rights, despite its genesis in a system of law that justified colonisation, has opened up opportunities to reframe fixed ideas of law and culture. PMID:29670026

Indigenous Health and Human Rights: A Reflection on Law and Culture.

Science.gov (United States)

Mazel, Odette

2018-04-18

In Australia, Aboriginal and Torres Strait Islander peoples bear a greater burden of disease and have lower life expectancy than their non-Indigenous counterparts. These combined indicators are evidence of an entrenched health crisis in the Indigenous population that is linked to systemic disadvantage over many decades. In an effort to improve life expectancy and lessen the burden of disease, a number of strategies and national frameworks now embed a human rights-based approach to achieving health equality. This paper explores the application of human rights to Indigenous health and examines the inherent tensions that exist in engaging a system of law based on universal assumptions of the Enlightenment to advance Indigenous rights. What becomes apparent through this exploration is that the strategic approach of Indigenous peoples’ use of human rights, despite its genesis in a system of law that justified colonisation, has opened up opportunities to reframe fixed ideas of law and culture.

Population dynamics and genetic diversity of C4 strains of human enterovirus 71 in Mainland China, 1998-2010.

Directory of Open Access Journals (Sweden)

Dawei Guan

Full Text Available BACKGROUND: Since 1997, several countries within the Asian Pacific region have been affected by one or more massive outbreaks of Hand Foot and Mouth Disease (HFMD. Virus typing experiments revealed that these outbreaks were caused by strains of human enterovirus 71 (EV71 belonging to several different, recently emerged subgenogroups. In mainland China, a different situation was observed. The first outbreak, localized in Shangdong Province, was reported in 2007, and was followed by a wide-spread outbreak in mainland China in 2008. Since then, numbers of reported HFMD cases have been persistently high. METHODOLOGY/PRINCIPAL FINDINGS: To gain insight in the epidemiological behavior of EV71 in China, we studied genetic diversity and EV71 population dynamics to address whether the increase in number of reported EV71 infections reflects a real increase in viral spread or is just the result of increased awareness and surveillance. We used systematically collected VP1 gene sequences of 257 EV71 strains collected in Guangdong province from 2008 to 2010 as part of HFMD surveillance activities, and supplemented them with 305 GenBank EV71 reference stains collected in China from 1998 to 2010. All isolates from Guangdong Province belonged to subgenogroup C4. Viral population dynamics indicated that the increased reporting of HFMD in China since 2007 reflects a real increase in viral spread and continued replacement of viral lineages through time. Amino acid sequence comparisons revealed substitution of amino acid in residues 22, 145 and 289 through time regularly with the VP1 gene of EV71 strains isolated in mainland China from 1998 to 2010. CONCLUSIONS: EV71 strains isolated in mainland China mainly belonged to subgenogroup C4. There was exponential growth of the EV71 virus population in 2007 and 2008. There was amino acid substitution through time regularly with the VP1 gene which possibly increased viral spread and/or ability of the virus to circulate

Adventures in human population biology.

Science.gov (United States)

Baker, P T

1996-01-01

This article is a memoir of anthropologist Paul Baker's professional life. The introduction notes that the field of anthropology was altered by the impact of World War II when physical anthropologists provided vital information to the military. After the war, the GI bill supported the undergraduate and graduate studies of veterans, including Baker. After describing his academic training at the University of New Mexico and Harvard, Baker details his research training and field work in the desert for the US Climatic Research Laboratory and his work identifying the dead in Japan for the Quartermaster unit. Baker then traces his academic career at the Pennsylvania State University during which he directed two multidisciplinary research efforts for the International Biological Programme, one that sought to understand human adaptability at high altitude in Peru and another that studied migration and modernization in Samoa. Baker's last administrative positions were as staff consultant to the Man and the Biosphere (MAB) program and as chair of the US MAB committee. Baker retired from academic life at age 60 in 1987 and has devoted his time to reading and to helping organize professional associations in anthropology, especially those devoted to furthering internationally organized scientific efforts. Baker concludes this memoir by acknowledging the growth and development of the discipline of human population biology.

Age and gender affect the composition of fungal population of the human gastrointestinal tract

Directory of Open Access Journals (Sweden)

Francesco Strati

2016-08-01

Full Text Available The fungal component of the human gut microbiota has been neglected for long time due to the low relative abundance of fungi with respect to bacteria, and only recently few reports have explored its composition and dynamics in health or disease. The application of metagenomics methods to the full understanding of fungal communities is currently limited by the under representation of fungal DNA with respect to the bacterial one, as well as by the limited ability to discriminate passengers from colonizers. Here we investigated the gut mycobiota of a cohort of healthy subjects in order to reduce the gap of knowledge concerning fungal intestinal communities in the healthy status further screening for phenotypical traits that could reflect fungi adaptation to the host. We studied the fecal fungal populations of 111 healthy subjects by means of cultivation on fungal selective media and by amplicon-based ITS1 metagenomics analysis on a subset of 57 individuals. We then characterized the isolated fungi for their tolerance to gastrointestinal tract-like challenges and their susceptibility to antifungals. A total of 34 different fungal species were isolated showing several phenotypic characteristics associated with intestinal environment such as tolerance to body temperature (37°C, to acidic and oxidative stress and to bile salts exposure. We found a high frequency of azoles resistance in fungal isolates, with potential and significant clinical impact. Analyses of fungal communities revealed that the human gut mycobiota differs in function of individuals’ life stage in a gender-related fashion. The combination of metagenomics and fungal cultivation allowed an in-depth understanding of the fungal intestinal community structure associated to the healthy status and the commensalism-related traits of isolated fungi. We further discussed comparatively the results of sequencing and cultivation to critically evaluate the application of metagenomics

Response of human populations to large-scale emergencies

Science.gov (United States)

Bagrow, James; Wang, Dashun; Barabási, Albert-László

2010-03-01

Until recently, little quantitative data regarding collective human behavior during dangerous events such as bombings and riots have been available, despite its importance for emergency management, safety and urban planning. Understanding how populations react to danger is critical for prediction, detection and intervention strategies. Using a large telecommunications dataset, we study for the first time the spatiotemporal, social and demographic response properties of people during several disasters, including a bombing, a city-wide power outage, and an earthquake. Call activity rapidly increases after an event and we find that, when faced with a truly life-threatening emergency, information rapidly propagates through a population's social network. Other events, such as sports games, do not exhibit this propagation.

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

Science.gov (United States)

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

2014-09-01

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

Surveillance for yellow Fever virus in non-human primates in southern Brazil, 2001-2011: a tool for prioritizing human populations for vaccination.

Directory of Open Access Journals (Sweden)

Marco A B Almeida

2014-03-01

Full Text Available In Brazil, epizootics among New World monkey species may indicate circulation of yellow fever (YF virus and provide early warning of risk to humans. Between 1999 and 2001, the southern Brazilian state of Rio Grande do Sul initiated surveillance for epizootics of YF in non-human primates to inform vaccination of human populations. Following a YF outbreak, we analyzed epizootic surveillance data and assessed YF vaccine coverage, timeliness of implementation of vaccination in unvaccinated human populations. From October 2008 through June 2009, circulation of YF virus was confirmed in 67 municipalities in Rio Grande do Sul State; vaccination was recommended in 23 (34% prior to the outbreak and in 16 (24% within two weeks of first epizootic report. In 28 (42% municipalities, vaccination began more than two weeks after first epizootic report. Eleven (52% of 21 laboratory-confirmed human YF cases occurred in two municipalities with delayed vaccination. By 2010, municipalities with confirmed YF epizootics reported higher vaccine coverage than other municipalities that began vaccination. In unvaccinated human populations timely response to epizootic events is critical to prevent human yellow fever cases.

Concept Mapping in the Humanities to Facilitate Reflection: Externalizing the Relationship between Public and Personal Learning

Science.gov (United States)

Kandiko, Camille; Hay, David; Weller, Saranne

2013-01-01

This article discusses how mapping techniques were used in university teaching in a humanities subject. The use of concept mapping was expanded as a pedagogical tool, with a focus on reflective learning processes. Data were collected through a longitudinal study of concept mapping in a university-level Classics course. This was used to explore how…

A highly variable segment of human subterminal 16p reveals a history of population growth for modern humans outside Africa

Science.gov (United States)

Alonso, Santos; Armour, John A. L.

2001-01-01

We have sequenced a highly polymorphic subterminal noncoding region from human chromosome 16p13.3, flanking the 5′ end of the hypervariable minisatellite MS205, in 100 chromosomes sampled from different African and Euroasiatic populations. Coalescence analysis indicates that the time to the most recent common ancestor (approximately 1 million years) predates the appearance of anatomically modern human forms. The root of the network describing this variability lies in Africa. African populations show a greater level of diversity and deeper branches. Most Euroasiatic variability seems to have been generated after a recent out-of-Africa range expansion. A history of population growth is the most likely scenario for the Euroasiatic populations. This pattern of nuclear variability can be reconciled with inferences based on mitochondrial DNA. PMID:11158547

Reconstructing human pancreatic differentiation by mapping specific cell populations during development

DEFF Research Database (Denmark)

Ramond, Cyrille; Glaser, Nicolas; Berthault, Claire

2017-01-01

. Endocrine maturation progresses by up-regulating SUSD2 and lowering ECAD levels. Finally, in vitro differentiation of pancreatic endocrine cells derived from human pluripotent stem cells mimics key in vivo events. Our work paves the way to extend our understanding of the origin of mature human pancreatic......Information remains scarce on human development compared to animal models. Here, we reconstructed human fetal pancreatic differentiation using cell surface markers. We demonstrate that at 7weeks of development, the glycoprotein 2 (GP2) marks a multipotent cell population that will differentiate...... cell types and how such lineage decisions are regulated....

Recording human cortical population spikes non-invasively--An EEG tutorial.

Science.gov (United States)

Waterstraat, Gunnar; Fedele, Tommaso; Burghoff, Martin; Scheer, Hans-Jürgen; Curio, Gabriel

2015-07-30

Non-invasively recorded somatosensory high-frequency oscillations (sHFOs) evoked by electric nerve stimulation are markers of human cortical population spikes. Previously, their analysis was based on massive averaging of EEG responses. Advanced neurotechnology and optimized off-line analysis can enhance the signal-to-noise ratio of sHFOs, eventually enabling single-trial analysis. The rationale for developing dedicated low-noise EEG technology for sHFOs is unfolded. Detailed recording procedures and tailored analysis principles are explained step-by-step. Source codes in Matlab and Python are provided as supplementary material online. Combining synergistic hardware and analysis improvements, evoked sHFOs at around 600 Hz ('σ-bursts') can be studied in single-trials. Additionally, optimized spatial filters increase the signal-to-noise ratio of components at about 1 kHz ('κ-bursts') enabling their detection in non-invasive surface EEG. sHFOs offer a unique possibility to record evoked human cortical population spikes non-invasively. The experimental approaches and algorithms presented here enable also non-specialized EEG laboratories to combine measurements of conventional low-frequency EEG with the analysis of concomitant cortical population spike responses. Copyright © 2014 Elsevier B.V. All rights reserved.

Modification of the Fitzpatrick system of skin phototype classification for the Indian population, and its correlation with narrowband diffuse reflectance spectrophotometry.

Science.gov (United States)

Sharma, V K; Gupta, V; Jangid, B L; Pathak, M

2018-04-01

The Fitzpatrick classification for skin phototyping is widely used, but its usefulness in dark-skinned populations has been questioned by some researchers. Recently, skin colour measurement has been proposed for phototyping skin colour objectively. To modify the Fitzpatrick system of skin phototyping for the Indian population and to study its correlation with skin colour using narrowband diffuse reflectance spectrophotometry METHODS: Answer choices for three items (eye colour, hair colour, colour of unexposed skin) out of 10 in the original Fitzpatrick questionnaire were modified, followed by self-administration of the original and the modified Fitzpatrick questionnaire by 70 healthy Indian volunteers. Skin colour (melanin and erythema indices) was measured from two photoexposed and two photoprotected sites using a narrowband reflectance spectrophotometer. The mean ± SD scores for the original and modified Fitzpatrick questionnaires were 25.40 ± 4.49 and 23.89 ± 4.82, respectively (r = 0.97, P Spectrophotometry can be a useful objective tool for skin phototyping. © 2018 British Association of Dermatologists.

Continuous spatial representations in the olfactory bulb may reflect perceptual categories

Directory of Open Access Journals (Sweden)

Benjamin eAuffarth

2011-10-01

Full Text Available In sensory processing of odors, the olfactory bulb is an important relay station, where odor representations are noise-filtered, sharpened, and possibly re-organized. An organization by perceptual qualities has been found previously in the piriform cortex, however several recent studies indicate that the olfactory bulb code reflects behaviorally relevant dimensions spatially as well as at the population level. We apply a statistical analysis on 2-deoxyglucose images, taken over the entire bulb of glomerular layer of the rat, in order to see how the recognition of odors in the nose is translated into a map of odor quality in the brain. We first confirm previous studies that the first principal component could be related to pleasantness, however the next higher principal components are not directly clear. We then find mostly continuous spatial representations for perceptual categories. We compare the space spanned by spatial and population codes to human reports of perceptual similarity between odors and our results suggest that perceptual categories could be already embedded in glomerular activations and that spatial representations give a better match than population codes. This suggests that human and rat perceptual dimensions of odorant coding are related and indicates that perceptual qualities could be represented as continuous spatial codes of the olfactory bulb glomerulus population.

Population exposure from the nuclear fuel cycle

International Nuclear Information System (INIS)

Alpen, E.L.; Chester, R.O.; Fisher, D.R.

1988-01-01

The papers in this volume reflect the latest research on the nature and degree of exposure to human populations from ionizing radiation that results from the production of commercial nuclear power. The conference comprised representatives from such notable organizations as Brookhaven National Laboratory, the Inhalation Toxicology Research Institute and Pacific Northwest Laboratories. Issues addressed include the effects on humans of the mining and extraction of uranium and the fabrication of fuel for nuclear reactors, the decommissioning and disposal of facilities that are no longer useful or efficient and the likelihood of major nuclear accidents. Each document will have to be cataloged separately

Strategies to work with HLA data in human populations for histocompatibility, clinical transplantation, epidemiology and population genetics: HLA-NET methodological recommendations.

Science.gov (United States)

Sanchez-Mazas, A; Vidan-Jeras, B; Nunes, J M; Fischer, G; Little, A-M; Bekmane, U; Buhler, S; Buus, S; Claas, F H J; Dormoy, A; Dubois, V; Eglite, E; Eliaou, J F; Gonzalez-Galarza, F; Grubic, Z; Ivanova, M; Lie, B; Ligeiro, D; Lokki, M L; da Silva, B Martins; Martorell, J; Mendonça, D; Middleton, D; Voniatis, D Papioannou; Papasteriades, C; Poli, F; Riccio, M E; Vlachou, M Spyropoulou; Sulcebe, G; Tonks, S; Nevessignsky, M Toungouz; Vangenot, C; van Walraven, A-M; Tiercy, J-M

2012-12-01

HLA-NET (a European COST Action) aims at networking researchers working in bone marrow transplantation, epidemiology and population genetics to improve the molecular characterization of the HLA genetic diversity of human populations, with an expected strong impact on both public health and fundamental research. Such improvements involve finding consensual strategies to characterize human populations and samples and report HLA molecular typings and ambiguities; proposing user-friendly access to databases and computer tools and defining minimal requirements related to ethical aspects. The overall outcome is the provision of population genetic characterizations and comparisons in a standard way by all interested laboratories. This article reports the recommendations of four working groups (WG1-4) of the HLA-NET network at the mid-term of its activities. WG1 (Population definitions and sampling strategies for population genetics' analyses) recommends avoiding outdated racial classifications and population names (e.g. 'Caucasian') and using instead geographic and/or cultural (e.g. linguistic) criteria to describe human populations (e.g. 'pan-European'). A standard 'HLA-NET POPULATION DATA QUESTIONNAIRE' has been finalized and is available for the whole HLA community. WG2 (HLA typing standards for population genetics analyses) recommends retaining maximal information when reporting HLA typing results. Rather than using the National Marrow Donor Program coding system, all ambiguities should be provided by listing all allele pairs required to explain each genotype, according to the formats proposed in 'HLA-NET GUIDELINES FOR REPORTING HLA TYPINGS'. The group also suggests taking into account a preliminary list of alleles defined by polymorphisms outside the peptide-binding sites that may affect population genetic statistics because of significant frequencies. WG3 (Bioinformatic strategies for HLA population data storage and analysis) recommends the use of programs capable

Analysing human genomes at different scales

DEFF Research Database (Denmark)

Liu, Siyang

The thriving of the Next-Generation sequencing (NGS) technologies in the past decade has dramatically revolutionized the field of human genetics. We are experiencing a wave of several large-scale whole genome sequencing studies of humans in the world. Those studies vary greatly regarding cohort...... will be reflected by the analysis of real data. This thesis covers studies in two human genome sequencing projects that distinctly differ in terms of studied population, sample size and sequencing depth. In the first project, we sequenced 150 Danish individuals from 50 trio families to 78x coverage....... The sophisticated experimental design enables high-quality de novo assembly of the genomes and provides a good opportunity for mapping the structural variations in the human population. We developed the AsmVar approach to discover, genotype and characterize the structural variations from the assemblies. Our...

Present spatial diversity patterns of Theobroma cacao L. in the neotropics reflect genetic differentiation in pleistocene refugia followed by human-influenced dispersal.

Science.gov (United States)

Thomas, Evert; van Zonneveld, Maarten; Loo, Judy; Hodgkin, Toby; Galluzzi, Gea; van Etten, Jacob

2012-01-01

Cacao (Theobroma cacao L.) is indigenous to the Amazon basin, but is generally believed to have been domesticated in Mesoamerica for the production of chocolate beverage. However, cacao's distribution of genetic diversity in South America is also likely to reflect pre-Columbian human influences that were superimposed on natural processes of genetic differentiation. Here we present the results of a spatial analysis of the intra-specific diversity of cacao in Latin America, drawing on a dataset of 939 cacao trees genotypically characterized by means of 96 SSR markers. To assess continental diversity patterns we performed grid-based calculations of allelic richness, Shannon diversity and Nei gene diversity, and distinguished different spatially coherent genetic groups by means of cluster analysis. The highest levels of genetic diversity were observed in the Upper Amazon areas from southern Peru to the Ecuadorian Amazon and the border areas between Colombia, Peru and Brazil. On the assumption that the last glaciation (22,000-13,000 BP) had the greatest pre-human impact on the current distribution and diversity of cacao, we modeled the species' Pleistocene niche suitability and overlaid this with present-day diversity maps. The results suggest that cacao was already widely distributed in the Western Amazon before the onset of glaciation. During glaciations, cacao populations were likely to have been restricted to several refugia where they probably underwent genetic differentiation, resulting in a number of genetic clusters which are representative for, or closest related to, the original wild cacao populations. The analyses also suggested that genetic differentiation and geographical distribution of a number of other clusters seem to have been significantly affected by processes of human management and accompanying genetic bottlenecks. We discuss the implications of these results for future germplasm collection and in situ, on farm and ex situ conservation of cacao.

Continuous wave terahertz reflection imaging of human colorectal tissue

Science.gov (United States)

Doradla, Pallavi; Alavi, Karim; Joseph, Cecil S.; Giles, Robert H.

2013-03-01

Continuous wave terahertz (THz) imaging has the potential to offer a safe, non-ionizing, and nondestructive medical imaging modality for delineating colorectal cancer. Fresh excisions of normal colon tissue were obtained from surgeries performed at the University of Massachusetts Medical School, Worcester. Reflection measurements of thick sections of colorectal tissues, mounted in an aluminum sample holder, were obtained for both fresh and formalin fixed tissues. The two-dimensional reflection images were acquired by using an optically pumped far-infrared molecular gas laser operating at 584 GHz with liquid Helium cooled silicon bolometer detector. Using polarizers in the experiment both co-polarized and cross-polarized remittance form the samples was collected. Analysis of the images showed the importance of understanding the effects of formalin fixation while determining reflectance level of tissue response. The resulting co- and cross-polarized images of both normal and formalin fixed tissues showed uniform terahertz response over the entire sample area. Initial measurements indicated a co-polarized reflectance of 16%, and a cross-polarized reflectance of 0.55% from fresh excisions of normal colonic tissues.

Human population and activities in Forsmark. Site description

Energy Technology Data Exchange (ETDEWEB)

Miliander, Sofia; Punakivi, Mari; Kylaekorpi, Lasse; Rydgren, Bernt [SwedPower AB, Stockholm (Sweden)

2004-12-01

The Swedish Nuclear Fuel and Waste Management Co (SKB) is in the process of selecting a safe and environmentally acceptable location for a deep repository of radioactive waste. Two alternative locations are under investigation. These are Forsmark, Oesthammars kommun (kommun = municipality) and Simpevarp/Laxemar, Oskarshamns kommun. SKB has expressed the importance of describing the humans and their activities in these areas and therefore has this synthesis concerning the human population in Forsmark been produced.The description is a statistical synthesis, mainly based upon statistical data from SCB (Statistics Sweden) that has been collected, processed and analysed. The statistical data has not been verified through site inspections and interviews. When using statistical data, it is advisable to note that the data becomes more unreliable if the areas are small, with small populations.The data in this description is essential for future evaluations of the impact on the environment and its human population (Environmental Impact Assessments). The data is also important when modelling the potential flows of radio nuclides and calculating the risk of exposure in future safety assessments.The actual area for the study is in this report called 'the Forsmark area', an area of 19.5 km{sup 2} near Forsmark nuclear power plant. The land use in the Forsmark area differs notably from the land use in Uppsala laen (laen = county). Only 0.04% of the total area is developed (built-up) compared to 4.9% in Uppsala laen and only 4% is agricultural land compared to 25% in the county. Furthermore, there are far more forest, wetlands and water areas in the Forsmark area. The forest area represents as much as 72.5% of the total area.The Forsmark area is uninhabited, and its surroundings are very sparsely populated. In 2002, the population density in Forsmark was 1.8 inhabitants per square kilometre, which was 24 times lower than in Uppsala laen. The population density in the

Human population and activities in Forsmark. Site description

International Nuclear Information System (INIS)

Miliander, Sofia; Punakivi, Mari; Kylaekorpi, Lasse; Rydgren, Bernt

2004-12-01

The Swedish Nuclear Fuel and Waste Management Co (SKB) is in the process of selecting a safe and environmentally acceptable location for a deep repository of radioactive waste. Two alternative locations are under investigation. These are Forsmark, Oesthammars kommun (kommun = municipality) and Simpevarp/Laxemar, Oskarshamns kommun. SKB has expressed the importance of describing the humans and their activities in these areas and therefore has this synthesis concerning the human population in Forsmark been produced.The description is a statistical synthesis, mainly based upon statistical data from SCB (Statistics Sweden) that has been collected, processed and analysed. The statistical data has not been verified through site inspections and interviews. When using statistical data, it is advisable to note that the data becomes more unreliable if the areas are small, with small populations.The data in this description is essential for future evaluations of the impact on the environment and its human population (Environmental Impact Assessments). The data is also important when modelling the potential flows of radio nuclides and calculating the risk of exposure in future safety assessments.The actual area for the study is in this report called 'the Forsmark area', an area of 19.5 km 2 near Forsmark nuclear power plant. The land use in the Forsmark area differs notably from the land use in Uppsala laen (laen = county). Only 0.04% of the total area is developed (built-up) compared to 4.9% in Uppsala laen and only 4% is agricultural land compared to 25% in the county. Furthermore, there are far more forest, wetlands and water areas in the Forsmark area. The forest area represents as much as 72.5% of the total area.The Forsmark area is uninhabited, and its surroundings are very sparsely populated. In 2002, the population density in Forsmark was 1.8 inhabitants per square kilometre, which was 24 times lower than in Uppsala laen. The population density in the parish has been

Directional dominance on stature and cognition in diverse human populations

NARCIS (Netherlands)

P.K. Joshi (Peter); T. Esko (Tõnu); H. Mattsson (Hannele); N. Eklund (Niina); I. Gandin (Ilaria); T. Nutile; A.U. Jackson (Anne); C. Schurmann (Claudia); G.D. Smith; W. Zhang (Weihua); Y. Okada (Yukinori); A. Stancáková (Alena); J.D. Faul (Jessica D.); W. Zhao (Wei); T.M. Bartz (Traci M.); M.P. Concas (Maria Pina); N. Franceschini (Nora); S. Enroth (Stefan); V. Vitart (Veronique); S. Trompet (Stella); X. Guo (Xiuqing); D.I. Chasman (Daniel); J.R. O'Connel (Jeffrey R.); T. Corre (Tanguy); S.S. Nongmaithem (Suraj S.); Y. Chen (Yuning); M. Mangino (Massimo); D. Ruggiero; M. Traglia (Michela); A.-E. Farmaki (Aliki-Eleni); T. Kacprowski (Tim); A. Bjonnes (Andrew); A. van der Spek (Ashley); Y. Wu (Ying); A.K. Giri (Anil K.); L.R. Yanek (Lisa); L. Wang (Lihua); E. Hofer (Edith); C.A. Rietveld (Niels); O. McLeod (Olga); M. Cornelis (Marilyn); C. Pattaro (Cristian); N. Verweij (Niek); C. Baumbach (Clemens); A. Abdellaoui (Abdel); H. Warren (Helen); D. Vuckovic (Dragana); H. Mei (Hao); C. Bouchard (Claude); J.R.B. Perry (John); S. Cappellani (Stefania); S.S. Mirza (Saira); M.C. Benton (Miles C.); U. Broeckel (Ulrich); S.E. Medland (Sarah Elizabeth); P.A. Lind (Penelope); G. Malerba (Giovanni); A. Drong (Alexander); L. Yengo (Loic); L.F. Bielak (Lawrence F.); D. Zhi (Degui); P.J. van der Most (Peter); D. Shriner (Daniel); R. Mägi (Reedik); G. Hemani; T. Karaderi (Tugce); Z. Wang (Zhaoming); T. Liu (Tian); I. Demuth (Ilja); J.H. Zhao (Jing Hua); W. Meng (Weihua); L. Lataniotis (Lazaros); S.W. Van Der Laan (Sander W.); J.P. Bradfield (Jonathan); A.R. Wood (Andrew); A. Bonnefond (Amélie); T.S. Ahluwalia (Tarunveer Singh); L.M. Hall (Leanne M.); E. Salvi (Erika); S. Yazar (Seyhan); L. Carstensen (Lisbeth); H.G. De Haan (Hugoline G.); M. Abney (Mark); U. Afzal (Uzma); M.A. Allison (Matthew); N. Amin (Najaf); F.W. Asselbergs (Folkert W.); S.J.L. Bakker (Stephan); R.G. Barr (Graham); S.E. Baumeister (Sebastian); D.J. Benjamin (Daniel J.); S. Bergmann (Sven); E.A. Boerwinkle (Eric); E.P. Bottinger (Erwin P.); A. Campbell (Archie); A. Chakravarti (Aravinda); Y. Chan (Yingleong); S.J. Chanock (Stephen); C. Chen (Constance); Y.-D.I. Chen (Y.-D. Ida); F.S. Collins (Francis); J. Connell (John); A. Correa (Adolfo); L.A. Cupples (Adrienne); G.D. Smith; G. Davies (Gail); M. Dörr (Marcus); G.B. Ehret (Georg); S.B. Ellis (Stephen B.); B. Feenstra (Bjarke); M.F. Feitosa (Mary Furlan); I. Ford; C.S. Fox (Caroline); T.M. Frayling (Timothy); N. Friedrich (Nele); F. Geller (Frank); G. Scotland (Generation); I. Gillham-Nasenya (Irina); R.F. Gottesman (Rebecca); M.J. Graff (Maud J.L.); F. Grodstein (Francine); C. Gu (Charles); C. Haley (Chris); C.J. Hammond (Christopher); S.E. Harris (Sarah); T.B. Harris (Tamara); N. Hastie (Nick); N.L. Heard-Costa (Nancy); K. Heikkilä (Kauko); L.J. Hocking (Lynne); G. Homuth (Georg); J.J. Hottenga (Jouke Jan); J. Huang (Jian); J.E. Huffman (Jennifer); P.G. Hysi (Pirro); M.A. Ikram (Arfan); E. Ingelsson (Erik); A. Joensuu (Anni); A. Johansson (Åsa); P. Jousilahti (Pekka); J.W. Jukema (Jan Wouter); M. Kähönen (Mika); Y. Kamatani (Yoichiro); S. Kanoni (Stavroula); S.M. Kerr (Shona); N.M. Khan (Nazir M.); Ph.D. Koellinger (Philipp); H.A. Koistinen (Heikki A.); M.K. Kooner (Manraj K.); M. Kubo (Michiaki); J. Kuusisto (Johanna); J. Lahti (Jari); L.J. Launer (Lenore); R.A. Lea (Rodney A.); B. Lehne (Benjamin); T. Lehtimäki (Terho); D.C. Liewald (David C.); L. Lind (Lars); M. Loh (Marie); M.L. Lokki; S.J. London (Stephanie J.); S.J. Loomis (Stephanie J.); A. Loukola (Anu); Y. Lu (Yingchang); T. Lumley (Thomas); A. Lundqvist (Annamari); S. Männistö (Satu); P. Marques-Vidal (Pedro); C. Masciullo (Corrado); A. Matchan (Angela); J. Mathias (Jasmine); K. Matsuda (Koichi); J.B. Meigs (James); C. Meisinger (Christa); T. Meitinger (Thomas); C. Menni (Cristina); F.D. Mentch (Frank); E. Mihailov (Evelin); L. Milani (Lili); M.E. Montasser (May E.); G.W. Montgomery (Grant); A.C. Morrison (Alanna); R.H. Myers (Richard); R. Nadukuru (Rajiv); P. Navarro (Pau); M. Nalis (Mari); M.S. Nieminen (Markku S.); I.M. Nolte (Ilja M.); G.T. O'Connor (George); A. Ogunniyi (Adesola); S. Padmanabhan (Sandosh); W. Palmas (Walter); J.S. Pankow (James); I. Patarcic (Inga); F. Pavani (Francesca); P.A. Peyser (Patricia A.); K.H. Pietilainen (Kirsi Hannele); N.R. Poulter (Neil); I. Prokopenko (Inga); S. Ralhan (Sarju); P. Redmond (Paul); S.S. Rich (Stephen S.); H. Rissanen (Harri); A. Robino (Antonietta); L.M. Rose (Lynda M.); R.J. Rose (Richard J.); C. Sala (Cinzia); B. Salako (Babatunde); V. Salomaa (Veikko); A.-P. Sarin; R. Saxena (Richa); R. Schmidt (Reinhold); L.J. Scott (Laura); W.R. Scott (William R.); B. Sennblad (Bengt); S. Seshadri (Sudha); P. Sever (Peter); S. Shrestha (Smeeta); B.H. Smith (Blair); J.A. Smith (Jennifer A); N. Soranzo (Nicole); N. Sotoodehnia (Nona); L. Southam (Lorraine); A. Stanton (Alice); M.G. Stathopoulou (Maria G); K. Strauch (Konstantin); R.J. Strawbridge (Rona); M.J. Suderman (Matthew J.); N. Tandon (Nikhil); S.-T. Tang (Sian-Tsun); K.D. Taylor (Kent D.); B. Tayo (Bamidele); A.M. Töglhofer (Anna Maria); M. Tomaszewski (Maciej); N. Tsernikova (Natalia); J. Tuomilehto (Jaakko); A.G. Uitterlinden (André); D. Vaidya (Dhananjay); A. van Hylckama Vlieg (Astrid); J. van Setten (Jessica); T. Vasankari (Tuula); S. Vedantam (Sailaja); E. Vlachopoulou (Efthymia); D. Vozzi (Diego); E. Vuoksimaa (Eero); M. Waldenberger (Melanie); E.B. Ware (Erin B.); W. Wentworth-Shields (William); J. Whitfield (John); S. Wild (Sarah); G.A.H.M. Willemsen (Gonneke); C.S. Yajnik (Chittaranjan S.); J. Yao (Jie); G. Zaza (Gianluigi); X. Zhu (Xiaofeng); R.M. Salem (Rany); M. Melbye (Mads); H. Bisgaard (Hans); N.J. Samani (Nilesh); D. Cusi (Daniele); D.A. Mackey (David A.); R.S. Cooper (Richard S.); P. Froguel (Philippe); G. Pasterkamp (Gerard); S.F.A. Grant (Struan F.A.); H. Hakonarson (Hakon); L. Ferrucci (Luigi); R.A. Scott (Robert); A.D. Morris (Andrew); C.N.A. Palmer (Colin); G.V. Dedoussis (George V.); P. Deloukas (Panagiotis); L. Bertram (Lars); U. Lindenberger (Ulman); S.I. Berndt (Sonja); C.M. Lindgren (Cecilia); N.J. Timpson (Nicholas); A. Tönjes (Anke); P. Munroe (Patricia); T.I.A. Sørensen (Thorkild I.A.); C. Rotimi (Charles); D.K. Arnett (Donna); A.J. Oldehinkel (Albertine); S.L.R. Kardia (Sharon); B. Balkau (Beverley); G. Gambaro (Giovanni); A.P. Morris (Andrew); J.G. Eriksson (Johan G.); M.J. Wright (Margaret); N.G. Martin (Nicholas); S.C. Hunt (Steven); J.M. Starr (John); I.J. Deary (Ian J.); L.R. Griffiths (Lyn R.); H.W. Tiemeier (Henning); N. Pirastu (Nicola); J. Kaprio (Jaakko); N.J. Wareham (Nick); L. Perusse (Louis); J.G. Wilson (James); S. Girotto; M. Caulfield (Mark); O.T. Raitakari (Olli T.); D.I. Boomsma (Dorret); C. Gieger (Christian); P. van der Harst; A.A. Hicks (Andrew); P. Kraft (Peter); J. Sinisalo (Juha); P. Knekt; M. Johannesson (Magnus); P.K.E. Magnusson (Patrik K. E.); A. Hamsten (Anders); R. Schmidt (Reinhold); I.B. Borecki (Ingrid); E. Vartiainen (Erkki); D.M. Becker (Diane); D. Bharadwaj (Dwaipayan); K.L. Mohlke (Karen); M. Boehnke (Michael); C.M. van Duijn (Cornelia); D.K. Sanghera (Dharambir); A. Teumer (Alexander); E. Zeggini (Eleftheria); A. Metspalu (Andres); P. Gasparini (Paolo); S. Ulivi (Shelia); C. Ober (Carole); D. Toniolo (Daniela); I. Rudan (Igor); D.J. Porteous (David J.); M. Ciullo; T.D. Spector (Timothy); C. Hayward (Caroline); J. Dupuis (Josée); R.J.F. Loos (Ruth); A. Wright (Alan); G.R. Chandak (Giriraj); P. Vollenweider (Peter); A.R. Shuldiner (Alan); P.M. Ridker (Paul); J.I. Rotter (Jerome I.); N. Sattar (Naveed); U. Gyllensten (Ulf); K.E. North (Kari); M. Pirastu (Mario); B.M. Psaty (Bruce); D.R. Weir (David); M. Laakso (Markku); V. Gudnason (Vilmundur); A. Takahashi (Atsushi); J.C. Chambers (John C.); J.S. Kooner (Jaspal S.); D.P. Strachan (David P.); H. Campbell (Harry); J.N. Hirschhorn (Joel N.); M. Perola (Markus); O. Polasek (Ozren); J.F. Wilson (James)

2015-01-01

textabstractHomozygosity has long been associated with rare, often devastating, Mendelian disorders, and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness. However, the effect of the more distant parental relatedness that is common in modern human populations is

Radiation tumorigenesis in inbred laboratory animals and cancer risks in irradiated human populations. Two widely different problems

International Nuclear Information System (INIS)

Walinder, G.

1978-01-01

The mammal has efficient defence mechanisms against the development of tumours. These mechanisms are successively deteriorated by ionizing radiation when the dose increases beyond certain 'borderline levels'. Consequently, most animal strains demonstrate a bi-phasic dose-tumour relationship with a low-dose limb, the slope of which cannot be distinguished from zero, and a high-dose limb that increases with increasing doses. There are four or five exceptions to this 'rule' but in most of these cases the probable reasons for the deviations are known. Some human tumours as observed in epidemiological investigations do not demonstrate a similar clearly bi-phasic dose response. In all probability, this discrepancy does not reflect a higher susceptibility to radiation-induced tumours in man compared with other mammals. It is rather a consequence of a greater statistical variation in radiosensitivity in heterogeneous human populations than among inbred animals living standardized conditions. Accordingly, when maximum permissible dose levels are to be determined one should extrapolate from epidemiological data. Furthermore, these extrapolations should be linear if the data do not clearly deviate from a straight line, and if there are no scientific reasons to assume that a threshold exists. This formal method would not produce a biological description of what may happen in the low-dose area but rather an upper risk limit for the population studied. The real low-dose risk cannot be known. For the same pragmatic reason other radiological or non-radiological risks should be determined in the same manner, particularly when risks are to be compared. (author)

Human population and atmospheric carbon dioxide growth dynamics: Diagnostics for the future

Science.gov (United States)

Hüsler, A. D.; Sornette, D.

2014-10-01

We analyze the growth rates of human population and of atmospheric carbon dioxide by comparing the relative merits of two benchmark models, the exponential law and the finite-time-singular (FTS) power law. The later results from positive feedbacks, either direct or mediated by other dynamical variables, as shown in our presentation of a simple endogenous macroeconomic dynamical growth model describing the growth dynamics of coupled processes involving human population (labor in economic terms), capital and technology (proxies by CO2 emissions). Human population in the context of our energy intensive economies constitutes arguably the most important underlying driving variable of the content of carbon dioxide in the atmosphere. Using some of the best databases available, we perform empirical analyses confirming that the human population on Earth has been growing super-exponentially until the mid-1960s, followed by a decelerated sub-exponential growth, with a tendency to plateau at just an exponential growth in the last decade with an average growth rate of 1.0% per year. In contrast, we find that the content of carbon dioxide in the atmosphere has continued to accelerate super-exponentially until 1990, with a transition to a progressive deceleration since then, with an average growth rate of approximately 2% per year in the last decade. To go back to CO2 atmosphere contents equal to or smaller than the level of 1990 as has been the broadly advertised goals of international treaties since 1990 requires herculean changes: from a dynamical point of view, the approximately exponential growth must not only turn to negative acceleration but also negative velocity to reverse the trend.

Directional dominance on stature and cognition in diverse human populations

NARCIS (Netherlands)

Joshi, Peter K.; Esko, Tonu; Mattsson, Hannele; Eklund, Niina; Gandin, Ilaria; Nutile, Teresa; Jackson, Anne U.; Schurmann, Claudia; Smith, Albert V.; Zhang, Weihua; Okada, Yukinori; Stancakova, Alena; Faul, Jessica D.; Zhao, Wei; Bartz, Traci M.; Concas, Maria Pina; Franceschini, Nora; Enroth, Stefan; Vitart, Veronique; Trompet, Stella; Guo, Xiuqing; Chasman, Daniel I.; O'Connel, Jeffrey R.; Corre, Tanguy; Nongmaithem, Suraj S.; Chen, Yuning; Mangino, Massimo; Ruggiero, Daniela; Traglia, Michela; Farmaki, Aliki-Eleni; Kacprowski, Tim; Bjonnes, Andrew; van der Spek, Ashley; Wu, Ying; Giri, Anil K.; Yanek, Lisa R.; Wang, Lihua; Hofer, Edith; Rietveld, Cornelius A.; McLeod, Olga; Cornelis, Marilyn C.; Pattaro, Cristian; Verweij, Niek; Baumbach, Clemens; Abdellaoui, Abdel; Warren, Helen R.; Vuckovic, Dragana; Mei, Hao; Bouchard, Claude; Perry, John R. B.; Cappellani, Stefania; Mirza, Saira S.; Benton, Miles C.; Broeckel, Ulrich; Medland, Sarah E.; Lind, PenelopeA.; Malerba, Giovanni; Drong, Alexander; Yengo, Loic; Bielak, Lawrence F.; Zhi, Degui; van der Most, Peter J.; Shriner, Daniel; Maegi, Reedik; Hemani, Gibran; Karaderi, Tugce; Wang, Zhaoming; Liu, Tian; Demuth, Ilja; Zhao, Jing Hua; Meng, Weihua; Lataniotis, Lazaros; van der Laan, Sander W.; Bradfield, Jonathan P.; Wood, Andrew R.; Bonnefond, Amelie; Ahluwalia, Tarunveer S.; Hall, LeanneM.; Salvi, Erika; Yazar, Seyhan; Carstensen, Lisbeth; de Haan, Hugoline G.; Abney, Mark; Afzal, Uzma; Allison, Matthew A.; Amin, Najaf; Asselbergs, Folkert W.; Bakker, Stephan J. L.; Barr, R. Graham; Baumeister, Sebastian E.; Benjamin, Daniel J.; Bergmann, Sven; Boerwinkle, Eric; Bottinger, Erwin P.; Campbell, Archie; Chakravarti, Aravinda; Chan, Yingleong; Chanock, Stephen J.; Chen, Constance; Chen, Y. -D. Ida; Collins, Francis S.; Connell, John; Correa, Adolfo; Cupples, L. Adrienne; Smith, George Davey; Davies, Gail; Doerr, Marcus; Ehret, Georg; Ellis, Stephen B.; Feenstra, Bjarke; Feitosa, Mary F.; Ford, Ian; Fox, Caroline S.; Frayling, Timothy M.; Friedrich, Nele; Geller, Frank; Scotland, Generation; Gillham-Nasenya, Irina; Gottesman, Omri; Graff, Misa; Grodstein, Francine; Gu, Charles; Haley, Chris; Hammond, Christopher J.; Harris, Sarah E.; Harris, Tamara B.; Hastie, Nicholas D.; Heard-Costa, Nancy L.; Heikkila, Kauko; Hocking, Lynne J.; Homuth, Georg; Hottenga, Jouke-Jan; Huang, Jinyan; Huffman, Jennifer E.; Hysi, Pirro G.; Ikram, M. Arfan; Ingelsson, Erik; Joensuu, Anni; Johansson, Asa; Jousilahti, Pekka; Jukema, J. Wouter; Kahonen, Mika; Kamatani, Yoichiro; Kanoni, Stavroula; Kerr, Shona M.; Khan, Nazir M.; Koellinger, Philipp; Koistinen, Heikki A.; Kooner, Manraj K.; Kubo, Michiaki; Kuusisto, Johanna; Lahti, Jari; Launer, Lenore J.; Lea, Rodney A.; Lehne, Benjamin; Lehtimaki, Terho; Liewald, David C. M.; Lind, Lars; Loh, Marie; Lokki, Marja-Liisa; London, Stephanie J.; Loomis, Stephanie J.; Loukola, Anu; Lu, Yingchang; Lumley, Thomas; Lundqvist, Annamari; Mannisto, Satu; Marques-Vidal, Pedro; Masciullo, Corrado; Matchan, Angela; Mathias, Rasika A.; Matsuda, Koichi; Meigs, James B.; Meisinger, Christa; Meitinger, Thomas; Menni, Cristina; Mentch, Frank D.; Mihailov, Evelin; Milani, Lili; Montasser, May E.; Montgomery, GrantW.; Morrison, Alanna; Myers, Richard H.; Nadukuru, Rajiv; Navarro, Pau; Nelis, Mari; Nieminen, Markku S.; Nolte, Ilja M.; O'Connor, George T.; Ogunniyi, Adesola; Padmanabhan, Sandosh; Palmas, Walter R.; Pankow, James S.; Patarcic, Inga; Pavani, Francesca; Peyser, Patricia A.; Pietilainen, Kirsi; Poulter, Neil; Prokopenko, Inga; Ralhan, Sarju; Redmond, Paul; Rich, Stephen S.; Rissanen, Harri; Robino, Antonietta; Rose, Lynda M.; Rose, Richard; Sala, Cinzia; Salako, Babatunde; Salomaa, Veikko; Sarin, Antti-Pekka; Saxena, Richa; Schmidt, Helena; Scott, Laura J.; Scott, William R.; Sennblad, Bengt; Seshadri, Sudha; Sever, Peter; Shrestha, Smeeta; Smith, Blair H.; Smith, Jennifer A.; Soranzo, Nicole; Sotoodehnia, Nona; Southam, Lorraine; Stanton, Alice V.; Stathopoulou, Maria G.; Strauch, Konstantin; Strawbridge, Rona J.; Suderman, Matthew J.; Tandon, Nikhil; Tang, Sian-Tsun; Taylor, Kent D.; Tayo, Bamidele O.; Toeglhofer, Anna Maria; Tomaszewski, Maciej; Tsernikova, Natalia; Tuomilehto, Jaakko; Uitterlinden, Andre G.; Vaidya, Dhananjay; Vlieg, Astrid van Hylckama; van Setten, Jessica; Vasankari, Tuula; Vedantam, Sailaja; Vlachopoulou, Efthymia; Vozzi, Diego; Vuoksimaa, Eero; Waldenberger, Melanie; Ware, Erin B.; Wentworth-Shields, William; Whitfield, John B.; Wild, Sarah; Willemsen, Gonneke; Yajnik, Chittaranjan S.; Yao, Jie; Zaza, Gianluigi; Zhu, Xiaofeng; Salem, Rany M.; Melbye, Mads; Bisgaard, Hans; Samani, Nilesh J.; Cusi, Daniele; Mackey, David A.; Cooper, Richard S.; Froguel, Philippe; Pasterkamp, Gerard; Grant, Struan F. A.; Hakonarson, Hakon; Ferrucci, Luigi; Scott, Robert A.; Morris, Andrew D.; Palmer, Colin N. A.; Dedoussis, George; Deloukas, Panos; Bertram, Lars; Lindenberger, Ulman; Berndt, Sonja I.; Lindgren, Cecilia M.; Timpson, Nicholas J.; Toenjes, Anke; Munroe, Patricia B.; Sorensen, Thorkild I. A.; Rotimi, Charles N.; Arnett, Donna K.; Oldehinkel, Albertine J.; Kardia, Sharon L. R.; Balkau, Beverley; Gambaro, Giovanni; Morris, Andrew P.; Eriksson, Johan G.; Wright, Margie J.; Martin, Nicholas G.; Hunt, Steven C.; Starr, John M.; Deary, Ian J.; Griffiths, Lyn R.; Tiemeier, Henning; Pirastu, Nicola; Kaprio, Jaakko; Wareham, Nicholas J.; Perusse, Louis; Wilson, James G.; Girotto, Giorgia; Caulfield, Mark J.; Raitakari, Olli; Boomsma, Dorret I.; Gieger, Christian; van der Harst, Pim; Hicks, Andrew A.; Kraft, Peter; Sinisalo, Juha; Knekt, Paul; Johannesson, Magnus; Magnusson, Patrik K. E.; Hamsten, Anders; Schmidt, Reinhold; Borecki, Ingrid B.; Vartiainen, Erkki; Becker, Diane M.; Bharadwaj, Dwaipayan; Mohlke, Karen L.; Boehnke, Michael; van Duijn, Cornelia M.; Sanghera, Dharambir K.; Teumer, Alexander; Zeggini, Eleftheria; Metspalu, Andres; Gasparini, Paolo; Ulivi, Sheila; Ober, Carole; Toniolo, Daniela; Rudan, Igor; Porteous, David J.; Ciullo, Marina; Spector, Tim D.; Hayward, Caroline; Dupuis, Josee; Loos, Ruth J. F.; Wright, Alan F.; Chandak, Giriraj R.; Vollenweider, Peter; Shuldiner, Alan R.; Ridker, Paul M.; Rotter, Jerome I.; Sattar, Naveed; Gyllensten, Ulf; North, Kari E.; Pirastu, Mario; Psaty, Bruce M.; Weir, David R.; Laakso, Markku; Gudnason, Vilmundur; Takahashi, Atsushi; Chambers, John C.; Kooner, Jaspal S.; Strachan, David P.; Campbell, Harry; Hirschhorn, Joel N.; Perola, Markus; Polasek, Ozren; Wilson, James F.

2015-01-01

Homozygosity has long been associated with rare, often devastating, Mendelian disorders(1), and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness(2). However, the effect of the more distant parental relatedness that is common in modern human populations is less

Radiation exposure and radiation hazards of human population. Pt. 1

International Nuclear Information System (INIS)

Jacobi, W.

1982-01-01

The present Part I provides a survey on the various sources of natural and artificial radiation exposure of human population. Furthermore, biological radiation effects and radiation damages are surveyed. In an appendix, radiation types, radiation doses, and radiation dose units are explained. (orig./GSCH) [de

The Philippine Parliamentarians Conference on Human Survival, Population and Development. Summary.

Science.gov (United States)

1988-12-01

Proceedings of the 1st Philippine Parliamentarians' Conference on Human Survival, Population and Development (PARLCON '88) are summarized in this report. Conference participants included the House and Senate, government officials, representatives of nongovernmental organizations, international organizations, the diplomatic corps and the media. A message from the President was read, referring the "silent emergency" of malnutrition and infant mortality of over 100,000 yearly. The events taking place were a statement of objectives, a Senate Resolution welcoming the convening of the conference, an opening ceremony, a posthumous award to R. M. Sales, executive director of the UNFPA, and a final a plan of action. Much of the content of the above events was duplicated in the final plan, which was formulated in 17 points. Some of these key points were: recognition of the need for quality of life, the detrimental effect of rapid population growth on development, the right of spouses to plan family size within their ethical beliefs, and the need for political will to address development concerns. The conference recommended that parliament and local governments strive for a consensus on national policy regarding population; ensure that economic gains are not decimated by population growth, protect the environment, develop social and industrial infrastructure in outlying areas, pursue national self-reliance, promote the human right of choosing desired family size, endorse the small family norm, empower women by educational and income generating opportunities, gather national data on population, strengthen the Population Commission, support nongovernmental agencies that provide family planning services, and promote education on family planning.

Increasing cell culture population doublings for long-term growth of finite life span human cell cultures

Science.gov (United States)

Stampfer, Martha R; Garbe, James C

2015-02-24

Cell culture media formulations for culturing human epithelial cells are herein described. Also described are methods of increasing population doublings in a cell culture of finite life span human epithelial cells and prolonging the life span of human cell cultures. Using the cell culture media disclosed alone and in combination with addition to the cell culture of a compound associated with anti-stress activity achieves extended growth of pre-stasis cells and increased population doublings and life span in human epithelial cell cultures.

Genome-wide detection and characterization of positive selection in human populations.

Science.gov (United States)

Sabeti, Pardis C; Varilly, Patrick; Fry, Ben; Lohmueller, Jason; Hostetter, Elizabeth; Cotsapas, Chris; Xie, Xiaohui; Byrne, Elizabeth H; McCarroll, Steven A; Gaudet, Rachelle; Schaffner, Stephen F; Lander, Eric S; Frazer, Kelly A; Ballinger, Dennis G; Cox, David R; Hinds, David A; Stuve, Laura L; Gibbs, Richard A; Belmont, John W; Boudreau, Andrew; Hardenbol, Paul; Leal, Suzanne M; Pasternak, Shiran; Wheeler, David A; Willis, Thomas D; Yu, Fuli; Yang, Huanming; Zeng, Changqing; Gao, Yang; Hu, Haoran; Hu, Weitao; Li, Chaohua; Lin, Wei; Liu, Siqi; Pan, Hao; Tang, Xiaoli; Wang, Jian; Wang, Wei; Yu, Jun; Zhang, Bo; Zhang, Qingrun; Zhao, Hongbin; Zhao, Hui; Zhou, Jun; Gabriel, Stacey B; Barry, Rachel; Blumenstiel, Brendan; Camargo, Amy; Defelice, Matthew; Faggart, Maura; Goyette, Mary; Gupta, Supriya; Moore, Jamie; Nguyen, Huy; Onofrio, Robert C; Parkin, Melissa; Roy, Jessica; Stahl, Erich; Winchester, Ellen; Ziaugra, Liuda; Altshuler, David; Shen, Yan; Yao, Zhijian; Huang, Wei; Chu, Xun; He, Yungang; Jin, Li; Liu, Yangfan; Shen, Yayun; Sun, Weiwei; Wang, Haifeng; Wang, Yi; Wang, Ying; Xiong, Xiaoyan; Xu, Liang; Waye, Mary M Y; Tsui, Stephen K W; Xue, Hong; Wong, J Tze-Fei; Galver, Luana M; Fan, Jian-Bing; Gunderson, Kevin; Murray, Sarah S; Oliphant, Arnold R; Chee, Mark S; Montpetit, Alexandre; Chagnon, Fanny; Ferretti, Vincent; Leboeuf, Martin; Olivier, Jean-François; Phillips, Michael S; Roumy, Stéphanie; Sallée, Clémentine; Verner, Andrei; Hudson, Thomas J; Kwok, Pui-Yan; Cai, Dongmei; Koboldt, Daniel C; Miller, Raymond D; Pawlikowska, Ludmila; Taillon-Miller, Patricia; Xiao, Ming; Tsui, Lap-Chee; Mak, William; Song, You Qiang; Tam, Paul K H; Nakamura, Yusuke; Kawaguchi, Takahisa; Kitamoto, Takuya; Morizono, Takashi; Nagashima, Atsushi; Ohnishi, Yozo; Sekine, Akihiro; Tanaka, Toshihiro; Tsunoda, Tatsuhiko; Deloukas, Panos; Bird, Christine P; Delgado, Marcos; Dermitzakis, Emmanouil T; Gwilliam, Rhian; Hunt, Sarah; Morrison, Jonathan; Powell, Don; Stranger, Barbara E; Whittaker, Pamela; Bentley, David R; Daly, Mark J; de Bakker, Paul I W; Barrett, Jeff; Chretien, Yves R; Maller, Julian; McCarroll, Steve; Patterson, Nick; Pe'er, Itsik; Price, Alkes; Purcell, Shaun; Richter, Daniel J; Sabeti, Pardis; Saxena, Richa; Schaffner, Stephen F; Sham, Pak C; Varilly, Patrick; Altshuler, David; Stein, Lincoln D; Krishnan, Lalitha; Smith, Albert Vernon; Tello-Ruiz, Marcela K; Thorisson, Gudmundur A; Chakravarti, Aravinda; Chen, Peter E; Cutler, David J; Kashuk, Carl S; Lin, Shin; Abecasis, Gonçalo R; Guan, Weihua; Li, Yun; Munro, Heather M; Qin, Zhaohui Steve; Thomas, Daryl J; McVean, Gilean; Auton, Adam; Bottolo, Leonardo; Cardin, Niall; Eyheramendy, Susana; Freeman, Colin; Marchini, Jonathan; Myers, Simon; Spencer, Chris; Stephens, Matthew; Donnelly, Peter; Cardon, Lon R; Clarke, Geraldine; Evans, David M; Morris, Andrew P; Weir, Bruce S; Tsunoda, Tatsuhiko; Johnson, Todd A; Mullikin, James C; Sherry, Stephen T; Feolo, Michael; Skol, Andrew; Zhang, Houcan; Zeng, Changqing; Zhao, Hui; Matsuda, Ichiro; Fukushima, Yoshimitsu; Macer, Darryl R; Suda, Eiko; Rotimi, Charles N; Adebamowo, Clement A; Ajayi, Ike; Aniagwu, Toyin; Marshall, Patricia A; Nkwodimmah, Chibuzor; Royal, Charmaine D M; Leppert, Mark F; Dixon, Missy; Peiffer, Andy; Qiu, Renzong; Kent, Alastair; Kato, Kazuto; Niikawa, Norio; Adewole, Isaac F; Knoppers, Bartha M; Foster, Morris W; Clayton, Ellen Wright; Watkin, Jessica; Gibbs, Richard A; Belmont, John W; Muzny, Donna; Nazareth, Lynne; Sodergren, Erica; Weinstock, George M; Wheeler, David A; Yakub, Imtaz; Gabriel, Stacey B; Onofrio, Robert C; Richter, Daniel J; Ziaugra, Liuda; Birren, Bruce W; Daly, Mark J; Altshuler, David; Wilson, Richard K; Fulton, Lucinda L; Rogers, Jane; Burton, John; Carter, Nigel P; Clee, Christopher M; Griffiths, Mark; Jones, Matthew C; McLay, Kirsten; Plumb, Robert W; Ross, Mark T; Sims, Sarah K; Willey, David L; Chen, Zhu; Han, Hua; Kang, Le; Godbout, Martin; Wallenburg, John C; L'Archevêque, Paul; Bellemare, Guy; Saeki, Koji; Wang, Hongguang; An, Daochang; Fu, Hongbo; Li, Qing; Wang, Zhen; Wang, Renwu; Holden, Arthur L; Brooks, Lisa D; McEwen, Jean E; Guyer, Mark S; Wang, Vivian Ota; Peterson, Jane L; Shi, Michael; Spiegel, Jack; Sung, Lawrence M; Zacharia, Lynn F; Collins, Francis S; Kennedy, Karen; Jamieson, Ruth; Stewart, John

2007-10-18

With the advent of dense maps of human genetic variation, it is now possible to detect positive natural selection across the human genome. Here we report an analysis of over 3 million polymorphisms from the International HapMap Project Phase 2 (HapMap2). We used 'long-range haplotype' methods, which were developed to identify alleles segregating in a population that have undergone recent selection, and we also developed new methods that are based on cross-population comparisons to discover alleles that have swept to near-fixation within a population. The analysis reveals more than 300 strong candidate regions. Focusing on the strongest 22 regions, we develop a heuristic for scrutinizing these regions to identify candidate targets of selection. In a complementary analysis, we identify 26 non-synonymous, coding, single nucleotide polymorphisms showing regional evidence of positive selection. Examination of these candidates highlights three cases in which two genes in a common biological process have apparently undergone positive selection in the same population:LARGE and DMD, both related to infection by the Lassa virus, in West Africa;SLC24A5 and SLC45A2, both involved in skin pigmentation, in Europe; and EDAR and EDA2R, both involved in development of hair follicles, in Asia.

Population genetic inference from personal genome data: impact of ancestry and admixture on human genomic variation.

Science.gov (United States)

Kidd, Jeffrey M; Gravel, Simon; Byrnes, Jake; Moreno-Estrada, Andres; Musharoff, Shaila; Bryc, Katarzyna; Degenhardt, Jeremiah D; Brisbin, Abra; Sheth, Vrunda; Chen, Rong; McLaughlin, Stephen F; Peckham, Heather E; Omberg, Larsson; Bormann Chung, Christina A; Stanley, Sarah; Pearlstein, Kevin; Levandowsky, Elizabeth; Acevedo-Acevedo, Suehelay; Auton, Adam; Keinan, Alon; Acuña-Alonzo, Victor; Barquera-Lozano, Rodrigo; Canizales-Quinteros, Samuel; Eng, Celeste; Burchard, Esteban G; Russell, Archie; Reynolds, Andy; Clark, Andrew G; Reese, Martin G; Lincoln, Stephen E; Butte, Atul J; De La Vega, Francisco M; Bustamante, Carlos D

2012-10-05

Full sequencing of individual human genomes has greatly expanded our understanding of human genetic variation and population history. Here, we present a systematic analysis of 50 human genomes from 11 diverse global populations sequenced at high coverage. Our sample includes 12 individuals who have admixed ancestry and who have varying degrees of recent (within the last 500 years) African, Native American, and European ancestry. We found over 21 million single-nucleotide variants that contribute to a 1.75-fold range in nucleotide heterozygosity across diverse human genomes. This heterozygosity ranged from a high of one heterozygous site per kilobase in west African genomes to a low of 0.57 heterozygous sites per kilobase in segments inferred to have diploid Native American ancestry from the genomes of Mexican and Puerto Rican individuals. We show evidence of all three continental ancestries in the genomes of Mexican, Puerto Rican, and African American populations, and the genome-wide statistics are highly consistent across individuals from a population once ancestry proportions have been accounted for. Using a generalized linear model, we identified subtle variations across populations in the proportion of neutral versus deleterious variation and found that genome-wide statistics vary in admixed populations even once ancestry proportions have been factored in. We further infer that multiple periods of gene flow shaped the diversity of admixed populations in the Americas-70% of the European ancestry in today's African Americans dates back to European gene flow happening only 7-8 generations ago. Copyright © 2012 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Influence of physical activity in length of life of the human population in the context of changes

OpenAIRE

Ahmetović Zlatko; Romanov Romana; Dimitrić Mirjana

2014-01-01

Since the middle of the last century, the human population has increased exponentially. This trend is evident today. Human population has, for more than half a century been undergoing the period of its intensive development, increasing in number and the average length of life, creating the impression of a better life standard. Looking at the man as a bio-psycho-social being and the interactions it ones through the human population growth is brought in connection with its impact on the environ...

Review of epidemiological studies of human populations exposed to ionizing radiation

International Nuclear Information System (INIS)

Rao, B.S.

2002-01-01

Epidemiological studies undertaken in many radiation exposed cohorts have played an important role in the quantification of radiation risk. Follow up of nearly 100,000 A-bomb survivors by the Radiation Effects Research Foundation (RERF), constitutes the most comprehensive human epidemiological study. The study population covered both sexes, different age groups and dose ranges from a few mSv to 2-3 Sv. Among nearly 90,000 cohorts, as on 1990, 54% are alive. Among these, 35,000 are those exposed as children at the age<20 years. Nearly 20 % of the mortalities (8,040) were due to cancer. It was estimated from the analysis of these data that among the cancers observed in LSS cohorts, 425±45 cases (335 solid cancers+90 leukaemias) were attributable to radiation exposure. Assuming a value of two for DDREF, ICRP 60, 1991 estimated a cancer risk of 5% per Sv for low dose and low dose rate exposure conditions. There have been a number of efforts to study the human populations exposed to low level radiations. Epidemiological studies on nuclear workers from USA, UK and Canada constituting 95,673 workers spanning 2,124,526 person years was reported by Cardis et al. (1995). Total number of deaths were 15,825, of which 3,976 were cancer mortalities. The excess relative risk for all cancers excluding leukaemia is -0.07 per Sv (-0.4- +0.3) and for leukaemia (excluding CLL) is 2.18 (0.1-5.7). Epidemiological studies in high background radiation areas (HBRA) of Yangjiang, China and coastal Kerala showed no detectable increase in the incidence of cancers or of any genetic disorders. Epidemiological studies in human populations exposed to elevated background radiation for several generations did not show any increase in the genetic disorders. Recent information on the background incidence of monogenic disorders in human populations and the recoverability factor of induced genetic changes suggests a risk much lower than the earlier ICRP estimates. Many other epidemiological studies of

Current demographics suggest future energy supplies will be inadequate to slow human population growth.

Directory of Open Access Journals (Sweden)

John P DeLong

Full Text Available Influential demographic projections suggest that the global human population will stabilize at about 9-10 billion people by mid-century. These projections rest on two fundamental assumptions. The first is that the energy needed to fuel development and the associated decline in fertility will keep pace with energy demand far into the future. The second is that the demographic transition is irreversible such that once countries start down the path to lower fertility they cannot reverse to higher fertility. Both of these assumptions are problematic and may have an effect on population projections. Here we examine these assumptions explicitly. Specifically, given the theoretical and empirical relation between energy-use and population growth rates, we ask how the availability of energy is likely to affect population growth through 2050. Using a cross-country data set, we show that human population growth rates are negatively related to per-capita energy consumption, with zero growth occurring at ∼13 kW, suggesting that the global human population will stop growing only if individuals have access to this amount of power. Further, we find that current projected future energy supply rates are far below the supply needed to fuel a global demographic transition to zero growth, suggesting that the predicted leveling-off of the global population by mid-century is unlikely to occur, in the absence of a transition to an alternative energy source. Direct consideration of the energetic constraints underlying the demographic transition results in a qualitatively different population projection than produced when the energetic constraints are ignored. We suggest that energetic constraints be incorporated into future population projections.

Current demographics suggest future energy supplies will be inadequate to slow human population growth.

Science.gov (United States)

DeLong, John P; Burger, Oskar; Hamilton, Marcus J

2010-10-05

Influential demographic projections suggest that the global human population will stabilize at about 9-10 billion people by mid-century. These projections rest on two fundamental assumptions. The first is that the energy needed to fuel development and the associated decline in fertility will keep pace with energy demand far into the future. The second is that the demographic transition is irreversible such that once countries start down the path to lower fertility they cannot reverse to higher fertility. Both of these assumptions are problematic and may have an effect on population projections. Here we examine these assumptions explicitly. Specifically, given the theoretical and empirical relation between energy-use and population growth rates, we ask how the availability of energy is likely to affect population growth through 2050. Using a cross-country data set, we show that human population growth rates are negatively related to per-capita energy consumption, with zero growth occurring at ∼13 kW, suggesting that the global human population will stop growing only if individuals have access to this amount of power. Further, we find that current projected future energy supply rates are far below the supply needed to fuel a global demographic transition to zero growth, suggesting that the predicted leveling-off of the global population by mid-century is unlikely to occur, in the absence of a transition to an alternative energy source. Direct consideration of the energetic constraints underlying the demographic transition results in a qualitatively different population projection than produced when the energetic constraints are ignored. We suggest that energetic constraints be incorporated into future population projections.

Early modern human diversity suggests subdivided population structure and a complex out-of-Africa scenario

Science.gov (United States)

Gunz, Philipp; Bookstein, Fred L.; Mitteroecker, Philipp; Stadlmayr, Andrea; Seidler, Horst; Weber, Gerhard W.

2009-01-01

The interpretation of genetic evidence regarding modern human origins depends, among other things, on assessments of the structure and the variation of ancient populations. Because we lack genetic data from the time when the first anatomically modern humans appeared, between 200,000 and 60,000 years ago, instead we exploit the phenotype of neurocranial geometry to compare the variation in early modern human fossils with that in other groups of fossil Homo and recent modern humans. Variation is assessed as the mean-squared Procrustes distance from the group average shape in a representation based on several hundred neurocranial landmarks and semilandmarks. We find that the early modern group has more shape variation than any other group in our sample, which covers 1.8 million years, and that they are morphologically similar to recent modern humans of diverse geographically dispersed populations but not to archaic groups. Of the currently competing models of modern human origins, some are inconsistent with these findings. Rather than a single out-of-Africa dispersal scenario, we suggest that early modern humans were already divided into different populations in Pleistocene Africa, after which there followed a complex migration pattern. Our conclusions bear implications for the inference of ancient human demography from genetic models and emphasize the importance of focusing research on those early modern humans, in particular, in Africa. PMID:19307568

Parallel selection on TRPV6 in human populations

OpenAIRE

Hughes, David A; Tang, Kun; Strotmann, Rainer; Schöneberg, Torsten; Prenen, Jean; Nilius, Bernd; Stoneking, Mark

2008-01-01

We identified and examined a candidate gene for local directional selection in Europeans, TRPV6, and conclude that selection has acted on standing genetic variation at this locus, creating parallel soft sweep events in humans. A novel modification of the extended haplotype homozygosity (EHH) test was utilized, which compares EHH for a single allele across populations, to investigate the signature of selection at TRPV6 and neighboring linked loci in published data sets for Europeans, Asians an...

Human and animal studies: portals into the whole body and whole population response

Science.gov (United States)

Human and animal studies: portals into the whole body and whole population response Michael C. Madden1 and Brett Winters21US Environmental Protection Agency and 2University of North Carolina Human Studies Facility, Chapel Hill, North Carolina, USA Studies involving collection and...

Human impacts on large benthic foraminifers near a densely populated area of Majuro Atoll, Marshall Islands

International Nuclear Information System (INIS)

Osawa, Yoko; Fujita, Kazuhiko; Umezawa, Yu; Kayanne, Hajime; Ide, Yoichi; Nagaoka, Tatsutoshi; Miyajima, Toshihiro; Yamano, Hiroya

2010-01-01

Human impacts on sand-producing, large benthic foraminifers were investigated on ocean reef flats at the northeast Majuro Atoll, Marshall Islands, along a human population gradient. The densities of dominant foraminifers Calcarina and Amphistegina declined with distance from densely populated islands. Macrophyte composition on ocean reef flats differed between locations near sparsely or densely populated islands. Nutrient concentrations in reef-flat seawater and groundwater were high near or on densely populated islands. δ 15 N values in macroalgal tissues indicated that macroalgae in nearshore lagoons assimilate wastewater-derived nitrogen, whereas those on nearshore ocean reef flats assimilate nitrogen from other sources. These results suggest that increases in the human population result in high nutrient loading in groundwater and possibly into nearshore waters. High nutrient inputs into ambient seawater may have both direct and indirect negative effects on sand-producing foraminifers through habitat changes and/or the collapse of algal symbiosis.

Ethnicity and Population Structure in Personal Naming Networks

Science.gov (United States)

Mateos, Pablo; Longley, Paul A.; O'Sullivan, David

2011-01-01

Personal naming practices exist in all human groups and are far from random. Rather, they continue to reflect social norms and ethno-cultural customs that have developed over generations. As a consequence, contemporary name frequency distributions retain distinct geographic, social and ethno-cultural patterning that can be exploited to understand population structure in human biology, public health and social science. Previous attempts to detect and delineate such structure in large populations have entailed extensive empirical analysis of naming conventions in different parts of the world without seeking any general or automated methods of population classification by ethno-cultural origin. Here we show how ‘naming networks’, constructed from forename-surname pairs of a large sample of the contemporary human population in 17 countries, provide a valuable representation of cultural, ethnic and linguistic population structure around the world. This innovative approach enriches and adds value to automated population classification through conventional national data sources such as telephone directories and electoral registers. The method identifies clear social and ethno-cultural clusters in such naming networks that extend far beyond the geographic areas in which particular names originated, and that are preserved even after international migration. Moreover, one of the most striking findings of this approach is that these clusters simply ‘emerge’ from the aggregation of millions of individual decisions on parental naming practices for their children, without any prior knowledge introduced by the researcher. Our probabilistic approach to community assignment, both at city level as well as at a global scale, helps to reveal the degree of isolation, integration or overlap between human populations in our rapidly globalising world. As such, this work has important implications for research in population genetics, public health, and social science adding new

Shades of grey; Assessing the contribution of the magno- and parvocellular systems to neural processing of the retinal input in the human visual system from the influence of neural population size and its discharge activity on the VEP.

Science.gov (United States)

Marcar, Valentine L; Baselgia, Silvana; Lüthi-Eisenegger, Barbara; Jäncke, Lutz

2018-03-01

Retinal input processing in the human visual system involves a phasic and tonic neural response. We investigated the role of the magno- and parvocellular systems by comparing the influence of the active neural population size and its discharge activity on the amplitude and latency of four VEP components. We recorded the scalp electric potential of 20 human volunteers viewing a series of dartboard images presented as a pattern reversing and pattern on-/offset stimulus. These patterns were designed to vary both neural population size coding the temporal- and spatial luminance contrast property and the discharge activity of the population involved in a systematic manner. When the VEP amplitude reflected the size of the neural population coding the temporal luminance contrast property of the image, the influence of luminance contrast followed the contrast response function of the parvocellular system. When the VEP amplitude reflected the size of the neural population responding to the spatial luminance contrast property the image, the influence of luminance contrast followed the contrast response function of the magnocellular system. The latencies of the VEP components examined exhibited the same behavior across our stimulus series. This investigation demonstrates the complex interplay of the magno- and parvocellular systems on the neural response as captured by the VEP. It also demonstrates a linear relationship between stimulus property, neural response, and the VEP and reveals the importance of feedback projections in modulating the ongoing neural response. In doing so, it corroborates the conclusions of our previous study.

Inter-chromosomal variation in the pattern of human population genetic structure

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Baye Tesfaye M

2011-05-01

Full Text Available Abstract Emerging technologies now make it possible to genotype hundreds of thousands of genetic variations in individuals, across the genome. The study of loci at finer scales will facilitate the understanding of genetic variation at genomic and geographic levels. We examined global and chromosomal variations across HapMap populations using 3.7 million single nucleotide polymorphisms to search for the most stratified genomic regions of human populations and linked these regions to ontological annotation and functional network analysis. To achieve this, we used five complementary statistical and genetic network procedures: principal component (PC, cluster, discriminant, fixation index (FST and network/pathway analyses. At the global level, the first two PC scores were sufficient to account for major population structure; however, chromosomal level analysis detected subtle forms of population structure within continental populations, and as many as 31 PCs were required to classify individuals into homogeneous groups. Using recommended population ancestry differentiation measures, a total of 126 regions of the genome were catalogued. Gene ontology and networks analyses revealed that these regions included the genes encoding oculocutaneous albinism II (OCA2, hect domain and RLD 2 (HERC2, ectodysplasin A receptor (EDAR and solute carrier family 45, member 2 (SLC45A2. These genes are associated with melanin production, which is involved in the development of skin and hair colour, skin cancer and eye pigmentation. We also identified the genes encoding interferon-γ (IFNG and death-associated protein kinase 1 (DAPK1, which are associated with cell death, inflammatory and immunological diseases. An in-depth understanding of these genomic regions may help to explain variations in adaptation to different environments. Our approach offers a comprehensive strategy for analysing chromosome-based population structure and differentiation, and demonstrates the

Stabilization process of human population: a descriptive approach.

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Kayani, A K; Krotki, K J

1981-01-01

An attempt is made to inquire into the process of stabilization of a human population. The same age distribution distorted by past variations in fertility is subjected to several fixed schedules of fertility. The schedules are different from each other monotonically over a narrow range. The primary concern is with the process, almost year by year, through which the populations become stable. There is particular interest in the differential impact in the same original age distribution of the narrowly different fixed fertility schedules. The exercise is prepared in 3 stages: general background of the process of stabilization; methodology and data used; and analysis and discussion of the stabilization process. Among the several approaches through which the analysis of stable population is possible, 2 are popular: the integral equation and the projection matrix. In this presentation the interest is in evaluating the effects of fertility on the stabilization process of a population. Therefore, only 1 initial age distribution and only 1 life table but a variety of narrowly different schedules of fertility have been used. Specifically, the U.S. 1963 female population is treated as the initial population. The process of stabilization is viewed in the light of the changes in the slopes between 2 successive age groups of an age distribution. A high fertility schedule with the given initial age distribution and mortality level overcomes the oscillations more quickly than the low fertility schedule. Simulation confirms the intuitively expected positive relationship between the mean of the slope and the level of fertility. The variance of the slope distribution is an indicator of the aging of the distribution.

Type 2 diabetes risk alleles demonstrate extreme directional differentiation among human populations, compared to other diseases.

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Rong Chen

Full Text Available Many disease-susceptible SNPs exhibit significant disparity in ancestral and derived allele frequencies across worldwide populations. While previous studies have examined population differentiation of alleles at specific SNPs, global ethnic patterns of ensembles of disease risk alleles across human diseases are unexamined. To examine these patterns, we manually curated ethnic disease association data from 5,065 papers on human genetic studies representing 1,495 diseases, recording the precise risk alleles and their measured population frequencies and estimated effect sizes. We systematically compared the population frequencies of cross-ethnic risk alleles for each disease across 1,397 individuals from 11 HapMap populations, 1,064 individuals from 53 HGDP populations, and 49 individuals with whole-genome sequences from 10 populations. Type 2 diabetes (T2D demonstrated extreme directional differentiation of risk allele frequencies across human populations, compared with null distributions of European-frequency matched control genomic alleles and risk alleles for other diseases. Most T2D risk alleles share a consistent pattern of decreasing frequencies along human migration into East Asia. Furthermore, we show that these patterns contribute to disparities in predicted genetic risk across 1,397 HapMap individuals, T2D genetic risk being consistently higher for individuals in the African populations and lower in the Asian populations, irrespective of the ethnicity considered in the initial discovery of risk alleles. We observed a similar pattern in the distribution of T2D Genetic Risk Scores, which are associated with an increased risk of developing diabetes in the Diabetes Prevention Program cohort, for the same individuals. This disparity may be attributable to the promotion of energy storage and usage appropriate to environments and inconsistent energy intake. Our results indicate that the differential frequencies of T2D risk alleles may

Urban dogs in rural areas: Human-mediated movement defines dog populations in southern Chile.

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Villatoro, Federico J; Sepúlveda, Maximiliano A; Stowhas, Paulina; Silva-Rodríguez, Eduardo A

2016-12-01

Management strategies for dog populations and their diseases include reproductive control, euthanasia and vaccination, among others. However, the effectiveness of these strategies can be severely affected by human-mediated dog movement. If immigration is important, then the location of origin of dogs imported by humans will be fundamental to define the spatial scales over which population management and research should apply. In this context, the main objective of our study was to determine the spatial extent of dog demographic processes in rural areas and the proportion of dogs that could be labeled as immigrants at multiple spatial scales. To address our objective we conducted surveys in households located in a rural landscape in southern Chile. Interviews allowed us to obtain information on the demographic characteristics of dogs in these rural settings, human influence on dog mortality and births, the localities of origin of dogs living in rural areas, and the spatial extent of human-mediated dog movement. We found that most rural dogs (64.1%) were either urban dogs that had been brought to rural areas (40.0%), or adopted dogs that had been previously abandoned in rural roads (24.1%). Some dogs were brought from areas located as far as ∼700km away from the study area. Human-mediated movement of dogs, especially from urban areas, seems to play a fundamental role in the population dynamics of dogs in rural areas. Consequently, local scale efforts to manage dog populations or their diseases are unlikely to succeed if implemented in isolation, simply because dogs can be brought from surrounding urban areas or even distant locations. We suggest that efforts to manage or study dog populations and related diseases should be implemented using a multi-scale approach. Copyright © 2016 Elsevier B.V. All rights reserved.

Tick-borne infections in human and animal population worldwide

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José Brites-Neto

2015-03-01

Full Text Available The abundance and activity of ectoparasites and its hosts are affected by various abiotic factors, such as climate and other organisms (predators, pathogens and competitors presenting thus multiples forms of association (obligate to facultative, permanent to intermittent and superficial to subcutaneous developed during long co-evolving processes. Ticks are ectoparasites widespread globally and its eco epidemiology are closely related to the environmental conditions. They are obligatory hematophagous ectoparasites and responsible as vectors or reservoirs at the transmission of pathogenic fungi, protozoa, viruses, rickettsia and others bacteria during their feeding process on the hosts. Ticks constitute the second vector group that transmit the major number of pathogens to humans and play a role primary for animals in the process of diseases transmission. Many studies on bioecology of ticks, considering the information related to their population dynamics, to the host and the environment, comes possible the application and efficiency of tick control measures in the prevention programs of vector-borne diseases. In this review were considered some taxonomic, morphological, epidemiological and clinical fundamental aspects related to the tick-borne infections that affect human and animal populations.

The Driving Forces of Cultural Complexity : Neanderthals, Modern Humans, and the Question of Population Size.

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Fogarty, Laurel; Wakano, Joe Yuichiro; Feldman, Marcus W; Aoki, Kenichi

2017-03-01

The forces driving cultural accumulation in human populations, both modern and ancient, are hotly debated. Did genetic, demographic, or cognitive features of behaviorally modern humans (as opposed to, say, early modern humans or Neanderthals) allow culture to accumulate to its current, unprecedented levels of complexity? Theoretical explanations for patterns of accumulation often invoke demographic factors such as population size or density, whereas statistical analyses of variation in cultural complexity often point to the importance of environmental factors such as food stability, in determining cultural complexity. Here we use both an analytical model and an agent-based simulation model to show that a full understanding of the emergence of behavioral modernity, and the cultural evolution that has followed, depends on understanding and untangling the complex relationships among culture, genetically determined cognitive ability, and demographic history. For example, we show that a small but growing population could have a different number of cultural traits from a shrinking population with the same absolute number of individuals in some circumstances.

Effects of environmental radiation of Kori nuclear power plant on the human population

International Nuclear Information System (INIS)

Kim, Y.J.

1979-01-01

In order to clarify and protect the effects of environmental radiation according to the operation of Kori nuclear power plant on human population, the base line survey for the human monitoring, the fauna of land nocturnal insects, and the karyotypes of amphibian species which have been living around the power plant site were carried out. ''Kilchunri'' population which took for the human monitoring lie within a 2km distance from power plant site. Human monitoring, house and food characteristics, individual experience of X-ray exposures, human chromosome analysis and fauna of nocturnal land insects were surveyed and expressed in numerical tables. Chromosome number obtained from the amphibia which were collected around the power plant area was as follows; Kaloula borealis 2N=30, Rana amurensis 2N=26, Rana dybouskii 2N=24, Rana rugosa 2N=26, Rana migromaculata 2N=26, Rana plancyi 2N=26, Bombina orientalis 2N=24, Hyla arborea 2N=24, Bufo stejnegeri 2N=22, and Bufo bufo 2N=22. (author)

Human impacts on large benthic foraminifers near a densely populated area of Majuro Atoll, Marshall Islands.

Science.gov (United States)

Osawa, Yoko; Fujita, Kazuhiko; Umezawa, Yu; Kayanne, Hajime; Ide, Yoichi; Nagaoka, Tatsutoshi; Miyajima, Toshihiro; Yamano, Hiroya

2010-08-01

Human impacts on sand-producing, large benthic foraminifers were investigated on ocean reef flats at the northeast Majuro Atoll, Marshall Islands, along a human population gradient. The densities of dominant foraminifers Calcarina and Amphistegina declined with distance from densely populated islands. Macrophyte composition on ocean reef flats differed between locations near sparsely or densely populated islands. Nutrient concentrations in reef-flat seawater and groundwater were high near or on densely populated islands. delta(15)N values in macroalgal tissues indicated that macroalgae in nearshore lagoons assimilate wastewater-derived nitrogen, whereas those on nearshore ocean reef flats assimilate nitrogen from other sources. These results suggest that increases in the human population result in high nutrient loading in groundwater and possibly into nearshore waters. High nutrient inputs into ambient seawater may have both direct and indirect negative effects on sand-producing foraminifers through habitat changes and/or the collapse of algal symbiosis. Copyright 2010 Elsevier Ltd. All rights reserved.

Folk Narratives and the Reflection of (UTU Humanness in Shaaban Robert Adili na Nduzuze

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J.P. Madoshi

2015-08-01

Full Text Available This paper examines the novel Adili na Nduguze by Shaaban Robert. It seeks to explain how humanness is embedded in the plot of this prose fiction. The study uses Utu/Ubuntu as a theory of analyzing and explaining the events and the actions within this novel. The focus of the paper is to explore the plot of the novel in order to see how it reflects humanness (Utu/Ubuntu as it is perceived among the Bantu. The analysis is done by examining the reason of characters appellation and the author attention to diction which shows how royal characters intervene a conflict within this creative work. Also the study examines the novel in order to provide an account of the ontological conflict of two opposing beliefs in which a city is turned into stones (Mji Uliogeuka Mawe. Lastly, the paper attempts to inspect and explain reasons why Hasidi and Mwivu, Adili two brothers are turned into baboons, subjected to severe whipping from Adili and the cause of the removal of the curse placed upon them which subsequently makes them humans again.

Human population and activities at Simpevarp. Site description

Energy Technology Data Exchange (ETDEWEB)

Miliander, Sofia; Punakivi, Mari; Kylaekorpi, Lasse; Rydgren, Bernt [SwedPower AB, Stockholm (Sweden)

2004-12-01

The Swedish Nuclear Fuel and Waste Management Co (SKB) is in the process of selecting a safe and environmentally acceptable location for a deep repository of radioactive waste. Two alternative locations are under investigation. These are Forsmark, Oesthammars kommun (kommun = municipality) and Simpevarp/Laxemar, Oskarshamns kommun. SKB has expressed the importance of describing the humans and their activities in these areas and therefore has this synthesis concerning the human population in Forsmark been produced. The description is a statistical synthesis, mainly based upon statistical data from SCB (Statistics Sweden) that has been collected, processed and analysed. The statistical data has not been verified through site inspections and interviews. When using statistical data, it is advisable to note that the data becomes more unreliable if the areas are small, with small populations. The data in this description is essential for future evaluations of the impact on the environment and its human population (environmental impacts assessments). The data is also important when modelling the potential flows of radio nuclides and calculating the risk of exposure in future safety assessments. The actual area for the study is in this report called 'the Simpevarp area', an area of 127.0 km{sup 2} near Oskarshamn nuclear power plant. The land use in Simpevarp area differs notably from the land use in Kalmar laen. The forest area is far more dominating in Simpevarp area than in Kalmar laen and it represents as much as 89% compared to 63% of the total area. Only 4.4% of the area is arable land compared to 11.6% in Kalmar laen and only 0.3% is of other type (wetlands, bare rock, quarries, pites etc) compared to 15.6% in the county. The main observation is that Simpevarp area is a sparsely populated area located in a relatively lightly populated county. In 2002, the population density was 7.4 inhabitants/km{sup 2}, three times lower than in Kalmar laen. The

Human population and activities at Simpevarp. Site description

International Nuclear Information System (INIS)

Miliander, Sofia; Punakivi, Mari; Kylaekorpi, Lasse; Rydgren, Bernt

2004-12-01

The Swedish Nuclear Fuel and Waste Management Co (SKB) is in the process of selecting a safe and environmentally acceptable location for a deep repository of radioactive waste. Two alternative locations are under investigation. These are Forsmark, Oesthammars kommun (kommun = municipality) and Simpevarp/Laxemar, Oskarshamns kommun. SKB has expressed the importance of describing the humans and their activities in these areas and therefore has this synthesis concerning the human population in Forsmark been produced. The description is a statistical synthesis, mainly based upon statistical data from SCB (Statistics Sweden) that has been collected, processed and analysed. The statistical data has not been verified through site inspections and interviews. When using statistical data, it is advisable to note that the data becomes more unreliable if the areas are small, with small populations. The data in this description is essential for future evaluations of the impact on the environment and its human population (environmental impacts assessments). The data is also important when modelling the potential flows of radio nuclides and calculating the risk of exposure in future safety assessments. The actual area for the study is in this report called 'the Simpevarp area', an area of 127.0 km 2 near Oskarshamn nuclear power plant. The land use in Simpevarp area differs notably from the land use in Kalmar laen. The forest area is far more dominating in Simpevarp area than in Kalmar laen and it represents as much as 89% compared to 63% of the total area. Only 4.4% of the area is arable land compared to 11.6% in Kalmar laen and only 0.3% is of other type (wetlands, bare rock, quarries, pites etc) compared to 15.6% in the county. The main observation is that Simpevarp area is a sparsely populated area located in a relatively lightly populated county. In 2002, the population density was 7.4 inhabitants/km 2 , three times lower than in Kalmar laen. The demography statistics show

Biodiversity, Extinction, and Humanity’s Future: The Ecological and Evolutionary Consequences of Human Population and Resource Use

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Patrick L. Hindmarsh

2013-04-01

Full Text Available Human actions have altered global environments and reduced biodiversity by causing extinctions and reducing the population sizes of surviving species. Increasing human population size and per capita resource use will continue to have direct and indirect ecological and evolutionary consequences. As a result, future generations will inhabit a planet with significantly less wildlife, reduced evolutionary potential, diminished ecosystem services, and an increased likelihood of contracting infectious disease. The magnitude of these effects will depend on the rate at which global human population and/or per capita resource use decline to sustainable levels and the degree to which population reductions result from increased death rates rather than decreased birth rates.

Population crises and population cycles.

Science.gov (United States)

Russell, C; Russell, W M

2000-01-01

To prevent a population irretrievably depleting its resources, mammals have evolved a behavioural and physiological response to population crisis. When a mammalian population becomes dangerously dense, there is a reversal of behaviour. Co-operation and parental behaviour are replaced by competition, dominance and aggressive violence, leading to high mortality, especially of females and young, and a reduced population. The stress of overpopulation and the resulting violence impairs both the immune and the reproductive systems. Hence epidemics complete the crash of the population, and reproduction is slowed for three or four generations, giving the resources ample time to recover. In some mammal species, crisis and crisis response recur regularly, leading to cycles of population growth and relapse, oscillating about a fixed mean. Population crisis response and population cycles have been equally prominent in the history of human societies. But in man successive advances in food production have made possible growing populations, though with every such advance population soon outgrew resources again. Hence human cycles have been superimposed on a rising curve, producing a saw-tooth graph. Because advances in food production amounted to sudden disturbances in the relations between human populations and their environments, the crisis response in man has failed to avert famine and resource damage. In the large human societies evolved since the coming of settled agriculture and cities, the basic effects of violence, epidemics, famine and resource damage have been mediated by such specifically human disasters as inflation, unemployment, and political tyranny. An account of past crises, periods of relative relief from population pressure, and resulting cycles, is given for a number of regions: China, North Africa and Western Asia, the northern Mediterranean, and north-western Europe. The paper ends with an account of the present world-wide population crisis, and the solution

Reference man models based on normal data from human populations

International Nuclear Information System (INIS)

Tanaka, Gi-ichiro; Kawamura, Hisao

2000-01-01

Quantitative description of the physical, and metabolic parameters of the human body is the very basic for internal dosimetry. Compilation of anatomical and other types of data Asian populations for internal (and external) dosimetry is of grate significance because of the potential spread of nuclear energy use in the Asian region and the major contribution of the region to the world population (about 58%). It has been observed that some differences exist for habitat, race, body sizes and pattern of food consumption. In the early stage of revision of ICRP Reference man by the Task Group, Characteristics of the human body of non-European populations received considerable attention as well as those of the European populations of different sexes and ages. In this context, an IAEA-RCA Co-ordinated Research Program on Compilation of Anatomical, Physiological and Metabolic Characteristics for a Reference Asian Man endorsed. In later stages of reference Man revision, anatomical data for Asians was discusses together with those of European populations, presumably due to ICRP's decision of unanimous use of the Reference Man for radiation protection. Reference man models for adults and 15, 10, 5, 1, 0 year-old males and females of Asian populations were developed for use in internal and external dosimetry. Based on the concept of ICRP Reference Man (Publication 23), the reference values were derived from the normal organ mass data for Japanese and statistical data on the physique and nutrition of Japanese and Chinese. Also incorporated were variations in physical measurements, as observed in the above mentioned IAEA-RCA Co-ordinated Research Program. The work was partly carried out within the activities of the ICRP Task Group on Reference Man. The weight of the skeleton was adjusted following the revised values in Publication 70. This paper will report basic shared and non-shared characteristics of Reference Man' for Asians and ICRP Reference Man. (author)

Derivation and characterization of human embryonic stem cell lines from the Chinese population

Institute of Scientific and Technical Information of China (English)

Zhao Wu; Huimin Dai; Lei Qian; Qing Tian; Lei Xiao; Xiaojun Tan; Hui Li; Lingjun Rao; Lixiazi He; Lei Bao; Jing Liao; Chun Cui; Zhenyu Zuo; Qiao Li

2011-01-01

Human embryonic stem cells (hESCs) can self-renew indefinitely and differentiate into all cell types in the human body. Therefore, they are valuable in regenerative medicine, human developmental biology and drug discovery. A number of hESC lines have been derived from the Chinese population,but limited of them are available for research purposes. Here we report the derivation and characterization of two hESC lines derived from human blastocysts of Chinese origin. These hESCs express alkaline phosphatase and hESC-specific markers, including Oct4, Nanog, SSEA-3, SSEA-4,TRA-1-60 and TRA-1-81. They also have high levels of telomerase activity and normal karyotypes. These cells can form embryoid body in vitro and can be differentiated into all three germ layers in vivo by teratoma formation. The newly established hESCs will be distributed for research purposes.The availability of hESC lines from the Chinese population will facilitate studies on the differences in hESCs from different ethnic groups.

The Importance of Human Ecology at the Threshold of the Next Millennium: How Can Population Growth Be Stopped?

Science.gov (United States)

Nentwig, W.

Ecology is defined as the set of complex interactions between the biotic and abiotic environments. Human ecology concerns principally the population ecology "only" of Homo sapiens, but it also includes all aspects of global ecology because humans are the most important species. Human demography is characterized by a recent decline in mortality and fertility rates. These demographic transitions have largely been completed in industrialized countries, but not in the 140 developing countries. Approximately 100 countries are following the same demographic pattern as industrialized countries, however with a time delay of several generations. China has effectively reduced its population increase by means that would be unacceptable in Western democracies. Some 44 developing countries still show increasing population growth and no detectable demographic transition in birth rate. Thus one part of the world shows limited (and, in the long run, shrinking) population growth, and another continues with a strong increase. All populations are limited in their development by their sustainability by their environment, for example, food and energy resources, and the extent of pollution which the use of these resources produces. It is argued that in the case of human population the limits of sustainability have already been reached with the 6 billion humans alive today, since at least 20% of these suffer from hunger, natural resources are overexploited, and biodiversity is threatened. In the coming 200years it is more likely that the total population will substantially oscillate rather than approach the predicted 12 billion. The most important goal of human ecology should therefore be to slow population growth as far as possible.

Recombination gives a new insight in the effective population size and the history of the old world human populations.

Science.gov (United States)

Melé, Marta; Javed, Asif; Pybus, Marc; Zalloua, Pierre; Haber, Marc; Comas, David; Netea, Mihai G; Balanovsky, Oleg; Balanovska, Elena; Jin, Li; Yang, Yajun; Pitchappan, R M; Arunkumar, G; Parida, Laxmi; Calafell, Francesc; Bertranpetit, Jaume

2012-01-01

The information left by recombination in our genomes can be used to make inferences on our recent evolutionary history. Specifically, the number of past recombination events in a population sample is a function of its effective population size (Ne). We have applied a method, Identifying Recombination in Sequences (IRiS), to detect specific past recombination events in 30 Old World populations to infer their Ne. We have found that sub-Saharan African populations have an Ne that is approximately four times greater than those of non-African populations and that outside of Africa, South Asian populations had the largest Ne. We also observe that the patterns of recombinational diversity of these populations correlate with distance out of Africa if that distance is measured along a path crossing South Arabia. No such correlation is found through a Sinai route, suggesting that anatomically modern humans first left Africa through the Bab-el-Mandeb strait rather than through present Egypt.

Population genetic structure of the people of Qatar.

Science.gov (United States)

Hunter-Zinck, Haley; Musharoff, Shaila; Salit, Jacqueline; Al-Ali, Khalid A; Chouchane, Lotfi; Gohar, Abeer; Matthews, Rebecca; Butler, Marcus W; Fuller, Jennifer; Hackett, Neil R; Crystal, Ronald G; Clark, Andrew G

2010-07-09

People of the Qatar peninsula represent a relatively recent founding by a small number of families from three tribes of the Arabian Peninsula, Persia, and Oman, with indications of African admixture. To assess the roles of both this founding effect and the customary first-cousin marriages among the ancestral Islamic populations in Qatar's population genetic structure, we obtained and genotyped with Affymetrix 500k SNP arrays DNA samples from 168 self-reported Qatari nationals sampled from Doha, Qatar. Principal components analysis was performed along with samples from the Human Genetic Diversity Project data set, revealing three clear clusters of genotypes whose proximity to other human population samples is consistent with Arabian origin, a more eastern or Persian origin, and individuals with African admixture. The extent of linkage disequilibrium (LD) is greater than that of African populations, and runs of homozygosity in some individuals reflect substantial consanguinity. However, the variance in runs of homozygosity is exceptionally high, and the degree of identity-by-descent sharing generally appears to be lower than expected for a population in which nearly half of marriages are between first cousins. Despite the fact that the SNPs of the Affymetrix 500k chip were ascertained with a bias toward SNPs common in Europeans, the data strongly support the notion that the Qatari population could provide a valuable resource for the mapping of genes associated with complex disorders and that tests of pairwise interactions are particularly empowered by populations with elevated LD like the Qatari. Copyright 2010 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Key Inflammatory Processes in Human NASH Are Reflected in Ldlr-/-.Leiden Mice: A Translational Gene Profiling Study.

Science.gov (United States)

Morrison, Martine C; Kleemann, Robert; van Koppen, Arianne; Hanemaaijer, Roeland; Verschuren, Lars

2018-01-01

Introduction: It is generally accepted that metabolic inflammation in the liver is an important driver of disease progression in NASH and associated matrix remodeling/fibrosis. However, the exact molecular inflammatory mechanisms are poorly defined in human studies. Investigation of key pathogenic mechanisms requires the use of pre-clinical models, for instance for time-resolved studies. Such models must reflect molecular disease processes of importance in patients. Herein we characterized inflammation in NASH patients on the molecular level by transcriptomics and investigated whether key human disease pathways can be recapitulated experimentally in Ldlr -/- .Leiden mice, an established pre-clinical model of NASH. Methods: Human molecular inflammatory processes were defined using a publicly available NASH gene expression profiling dataset (GSE48452) allowing the comparison of biopsy-confirmed NASH patients with normal controls. Gene profiling data from high-fat diet (HFD)-fed Ldlr -/- .Leiden mice (GSE109345) were used for assessment of the translational value of these mice. Results: In human NASH livers, we observed regulation of 65 canonical pathways of which the majority was involved in inflammation (32%), lipid metabolism (16%), and extracellular matrix/remodeling (12%). A similar distribution of pathways across these categories, inflammation (36%), lipid metabolism (24%) and extracellular matrix/remodeling (8%) was observed in HFD-fed Ldlr -/- .Leiden mice. Detailed evaluation of these pathways revealed that a substantial proportion (11 out of 13) of human NASH inflammatory pathways was recapitulated in Ldlr -/- .Leiden mice. Furthermore, the activation state of identified master regulators of inflammation (i.e., specific transcription factors, cytokines, and growth factors) in human NASH was largely reflected in Ldlr -/- .Leiden mice, further substantiating its translational value. Conclusion: Human NASH is characterized by upregulation of specific

Distance from Africa, not climate, explains within-population phenotypic diversity in humans

Science.gov (United States)

Betti, Lia; Balloux, François; Amos, William; Hanihara, Tsunehiko; Manica, Andrea

2008-01-01

The relative importance of ancient demography and climate in determining worldwide patterns of human within-population phenotypic diversity is still open to debate. Several morphometric traits have been argued to be under selection by climatic factors, but it is unclear whether climate affects the global decline in morphological diversity with increasing geographical distance from sub-Saharan Africa. Using a large database of male and female skull measurements, we apply an explicit framework to quantify the relative role of climate and distance from Africa. We show that distance from sub-Saharan Africa is the sole determinant of human within-population phenotypic diversity, while climate plays no role. By selecting the most informative set of traits, it was possible to explain over half of the worldwide variation in phenotypic diversity. These results mirror those previously obtained for genetic markers and show that ‘bones and molecules’ are in perfect agreement for humans. PMID:19129123

Discovery of rare, diagnostic AluYb8/9 elements in diverse human populations.

Science.gov (United States)

Feusier, Julie; Witherspoon, David J; Scott Watkins, W; Goubert, Clément; Sasani, Thomas A; Jorde, Lynn B

2017-01-01

Polymorphic human Alu elements are excellent tools for assessing population structure, and new retrotransposition events can contribute to disease. Next-generation sequencing has greatly increased the potential to discover Alu elements in human populations, and various sequencing and bioinformatics methods have been designed to tackle the problem of detecting these highly repetitive elements. However, current techniques for Alu discovery may miss rare, polymorphic Alu elements. Combining multiple discovery approaches may provide a better profile of the polymorphic Alu mobilome. Alu Yb8/9 elements have been a focus of our recent studies as they are young subfamilies (~2.3 million years old) that contribute ~30% of recent polymorphic Alu retrotransposition events. Here, we update our ME-Scan methods for detecting Alu elements and apply these methods to discover new insertions in a large set of individuals with diverse ancestral backgrounds. We identified 5,288 putative Alu insertion events, including several hundred novel Alu Yb8/9 elements from 213 individuals from 18 diverse human populations. Hundreds of these loci were specific to continental populations, and 23 non-reference population-specific loci were validated by PCR. We provide high-quality sequence information for 68 rare Alu Yb8/9 elements, of which 11 have hallmarks of an active source element. Our subfamily distribution of rare Alu Yb8/9 elements is consistent with previous datasets, and may be representative of rare loci. We also find that while ME-Scan and low-coverage, whole-genome sequencing (WGS) detect different Alu elements in 41 1000 Genomes individuals, the two methods yield similar population structure results. Current in-silico methods for Alu discovery may miss rare, polymorphic Alu elements. Therefore, using multiple techniques can provide a more accurate profile of Alu elements in individuals and populations. We improved our false-negative rate as an indicator of sample quality for future

Long-Term Bird Assemblage Trends in Areas of High and Low Human Population Density

International Nuclear Information System (INIS)

Barrett, K.; Romagosa, C.M.; Williams, M.I.

2008-01-01

Urban areas are expanding globally, and the impact of high human population density (HHPD) on bird species richness remains unresolved. Studies primarily focus on species richness along an urban-to-rural gradient; however, some studies have analyzed larger-scale patterns and found results that contrast with those obtained at smaller scales. To move the discussion beyond static species richness patterns, we analyzed the effect of HHPD on bird assemblage dynamics (year-to-year extinction probability, turnover, changes in species richness) across the United States over a 25-year period. We found that bird assemblages in both high and low human population density areas changed significantly over the period of record. Specifically, bird assemblages increased in species richness on average. Assemblage change in areas of HHPD was not significantly different from assemblage change in areas with LHPD. These results suggest that human population density alone does not alter the persistence of avian assemblage patterns.

The population genomic landscape of human genetic structure, admixture history and local adaptation in Peninsular Malaysia.

Science.gov (United States)

Deng, Lian; Hoh, Boon Peng; Lu, Dongsheng; Fu, Ruiqing; Phipps, Maude E; Li, Shilin; Nur-Shafawati, Ab Rajab; Hatin, Wan Isa; Ismail, Endom; Mokhtar, Siti Shuhada; Jin, Li; Zilfalil, Bin Alwi; Marshall, Christian R; Scherer, Stephen W; Al-Mulla, Fahd; Xu, Shuhua

2014-09-01

Peninsular Malaysia is a strategic region which might have played an important role in the initial peopling and subsequent human migrations in Asia. However, the genetic diversity and history of human populations--especially indigenous populations--inhabiting this area remain poorly understood. Here, we conducted a genome-wide study using over 900,000 single nucleotide polymorphisms (SNPs) in four major Malaysian ethnic groups (MEGs; Malay, Proto-Malay, Senoi and Negrito), and made comparisons of 17 world-wide populations. Our data revealed that Peninsular Malaysia has greater genetic diversity corresponding to its role as a contact zone of both early and recent human migrations in Asia. However, each single Orang Asli (indigenous) group was less diverse with a smaller effective population size (N(e)) than a European or an East Asian population, indicating a substantial isolation of some duration for these groups. All four MEGs were genetically more similar to Asian populations than to other continental groups, and the divergence time between MEGs and East Asian populations (12,000--6,000 years ago) was also much shorter than that between East Asians and Europeans. Thus, Malaysian Orang Asli groups, despite their significantly different features, may share a common origin with the other Asian groups. Nevertheless, we identified traces of recent gene flow from non-Asians to MEGs. Finally, natural selection signatures were detected in a batch of genes associated with immune response, human height, skin pigmentation, hair and facial morphology and blood pressure in MEGs. Notable examples include SYN3 which is associated with human height in all Orang Asli groups, a height-related gene (PNPT1) and two blood pressure-related genes (CDH13 and PAX5) in Negritos. We conclude that a long isolation period, subsequent gene flow and local adaptations have jointly shaped the genetic architectures of MEGs, and this study provides insight into the peopling and human migration

Holocene fluctuations in human population demonstrate repeated links to food production and climate.

Science.gov (United States)

Bevan, Andrew; Colledge, Sue; Fuller, Dorian; Fyfe, Ralph; Shennan, Stephen; Stevens, Chris

2017-12-05

We consider the long-term relationship between human demography, food production, and Holocene climate via an archaeological radiocarbon date series of unprecedented sampling density and detail. There is striking consistency in the inferred human population dynamics across different regions of Britain and Ireland during the middle and later Holocene. Major cross-regional population downturns in population coincide with episodes of more abrupt change in North Atlantic climate and witness societal responses in food procurement as visible in directly dated plants and animals, often with moves toward hardier cereals, increased pastoralism, and/or gathered resources. For the Neolithic, this evidence questions existing models of wholly endogenous demographic boom-bust. For the wider Holocene, it demonstrates that climate-related disruptions have been quasi-periodic drivers of societal and subsistence change. Copyright © 2017 the Author(s). Published by PNAS.

Common features of sexual dimorphism in the cranial airways of different human populations.

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Bastir, Markus; Godoy, Paula; Rosas, Antonio

2011-11-01

Sexual dimorphism in the human craniofacial system is an important feature of intraspecific variation in recent and fossil humans. Although several studies have reported different morphological patterns of sexual dimorphism in different populations, this study searches for common morphological aspects related to functional anatomy of the respiratory apparatus. 3D geometric morphometrics were used to test the hypothesis that due to higher daily energy expenditure and associated greater respiratory air consumption as well as differences in body composition, males should have absolutely and relatively greater air passages in the bony cranial airways than females. We measured 25 3D landmarks in five populations (N = 212) of adult humans from different geographic regions. Male average cranial airways were larger in centroid sizes than female ones. Males tended to show relatively taller piriform apertures and, more consistently, relatively taller internal nasal cavities and choanae than females. Multivariate regressions and residual analysis further indicated that after standardizing to the same size, males still show relatively larger airway passages than females. Because the dimensions of the choanae are limiting factors for air transmission towards the noncranial part of the respiratory system, the identified sex-specific differences in cranial airways, possibly shared among human populations, may be linked with sex-specific differences in body size, composition, and energetics. These findings may be important to understanding trends in hominin facial evolution. Copyright © 2011 Wiley-Liss, Inc.

Meta-analysis of relationships between human offtake, total mortality and population dynamics of gray wolves (Canis lupus).

Science.gov (United States)

Creel, Scott; Rotella, Jay J

2010-09-29

Following the growth and geographic expansion of wolf (Canis lupus) populations reintroduced to Yellowstone National Park and central Idaho in 1995-1996, Rocky Mountain wolves were removed from the endangered species list in May 2009. Idaho and Montana immediately established hunting seasons with quotas equaling 20% of the regional wolf population. Combining hunting with predator control, 37.1% of Montana and Idaho wolves were killed in the year of delisting. Hunting and predator control are well-established methods to broaden societal acceptance of large carnivores, but it is unprecedented for a species to move so rapidly from protection under the Endangered Species Act to heavy direct harvest, and it is important to use all available data to assess the likely consequences of these changes in policy. For wolves, it is widely argued that human offtake has little effect on total mortality rates, so that a harvest of 28-50% per year can be sustained. Using previously published data from 21 North American wolf populations, we related total annual mortality and population growth to annual human offtake. Contrary to current conventional wisdom, there was a strong association between human offtake and total mortality rates across North American wolf populations. Human offtake was associated with a strongly additive or super-additive increase in total mortality. Population growth declined as human offtake increased, even at low rates of offtake. Finally, wolf populations declined with harvests substantially lower than the thresholds identified in current state and federal policies. These results should help to inform management of Rocky Mountain wolves.

Meta-analysis of relationships between human offtake, total mortality and population dynamics of gray wolves (Canis lupus.

Directory of Open Access Journals (Sweden)

Scott Creel

Full Text Available Following the growth and geographic expansion of wolf (Canis lupus populations reintroduced to Yellowstone National Park and central Idaho in 1995-1996, Rocky Mountain wolves were removed from the endangered species list in May 2009. Idaho and Montana immediately established hunting seasons with quotas equaling 20% of the regional wolf population. Combining hunting with predator control, 37.1% of Montana and Idaho wolves were killed in the year of delisting. Hunting and predator control are well-established methods to broaden societal acceptance of large carnivores, but it is unprecedented for a species to move so rapidly from protection under the Endangered Species Act to heavy direct harvest, and it is important to use all available data to assess the likely consequences of these changes in policy. For wolves, it is widely argued that human offtake has little effect on total mortality rates, so that a harvest of 28-50% per year can be sustained. Using previously published data from 21 North American wolf populations, we related total annual mortality and population growth to annual human offtake. Contrary to current conventional wisdom, there was a strong association between human offtake and total mortality rates across North American wolf populations. Human offtake was associated with a strongly additive or super-additive increase in total mortality. Population growth declined as human offtake increased, even at low rates of offtake. Finally, wolf populations declined with harvests substantially lower than the thresholds identified in current state and federal policies. These results should help to inform management of Rocky Mountain wolves.

Strategies to work with HLA data in human populations for histocompatibility, clinical transplantation, epidemiology and population genetics

DEFF Research Database (Denmark)

Sanchez-Mazas, A; Vidan-Jeras, B; Nunes, J M

2012-01-01

QUESTIONNAIRE' has been finalized and is available for the whole HLA community. WG2 (HLA typing standards for population genetics analyses) recommends retaining maximal information when reporting HLA typing results. Rather than using the National Marrow Donor Program coding system, all ambiguities should...... and fundamental research. Such improvements involve finding consensual strategies to characterize human populations and samples and report HLA molecular typings and ambiguities; proposing user-friendly access to databases and computer tools and defining minimal requirements related to ethical aspects. The overall......-Weinberg equilibrium and selective neutrality on data containing any number and kind of ambiguities. WG4 (Ethical issues) proposes to adopt thorough general principles for any HLA population study to ensure that it conforms to (inter)national legislation or recommendations/guidelines. All HLA-NET guidelines and tools...

Antimicrobial resistance and population structure of Staphylococcus epidermidis recovered from animals and humans.

Science.gov (United States)

Argudín, M Angeles; Vanderhaeghen, Wannes; Vandendriessche, Stien; Vandecandelaere, Ilse; André, François-Xavier; Denis, Olivier; Coenye, Tom; Butaye, Patrick

2015-07-09

While Staphylococcus epidermidis, as part of the commensal flora, is a well-known human opportunistic pathogen, only little is known about the genetic relatedness of S. epidermidis carriage isolates from animal and human origin. This study aimed to compare S. epidermidis recovered from livestock, livestock-farmers and humans associated with the hospital environment. A total of 193 S. epidermidis isolates from three populations [animals (n=33), farmers (n=86) and hospital-associated (n=74)] were characterized by broth microdilution antimicrobial susceptibility testing, staphylococcal cassette chromosome mec (SCCmec) typing, pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). The overall S. epidermidis nasal colonization rate was low in animals (1-9%) but high among farmers (75%). High levels of multi-resistance were found in all populations. Tetracycline resistance was high in animal and farmer isolates; resistance to erythromycin, clindamycin and trimethoprim was high in animal and hospital-associated isolates. Methicillin-resistant S. epidermidis - MRSE isolates were found in all collections, with 22 (67%) MRSE in animals, 44 (51%) MRSE in farmers and 42 (57%) MRSE associated with the hospital-setting. Known SCCmec types and variants were detected in 79% of MRSE; the rest were non-typeable cassettes. In total 79 PFGE-types were found, of which 22 were shared between livestock, farmers and the hospital settings. Clonal complex 2 was predominant in all three populations and most STs corresponded to types previously observed in community and nosocomial S. epidermidis populations. S. epidermidis isolates from livestock, farmers and hospital-setting showed a high level of diversity, but some clones can be found in humans as well as in animals. Copyright © 2015 Elsevier B.V. All rights reserved.

Ancient and contemporary DNA reveal a pre-human decline but no population bottleneck associated with recent human persecution in the kea (Nestor notabilis.

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Nicolas Dussex

Full Text Available The impact of population bottlenecks is an important factor to consider when assessing species survival. Population declines can considerably limit the evolutionary potential of species and make them more susceptible to stochastic events. New Zealand has a well documented history of decline of endemic avifauna related to human colonization. Here, we investigate the genetic effects of a recent population decline in the endangered kea (Nestor notabilis. Kea have undergone a long-lasting persecution between the late 1800s to 1970s where an estimated 150,000 kea were culled under a governmental bounty scheme. Kea now number 1,000-5,000 individuals in the wild and it is likely that the recent population decline may have reduced the genetic diversity of the species. Comparison of contemporary (n = 410, historical (n = 15 and fossil samples (n = 4 showed a loss of mitochondrial diversity since the end of the last glaciation (Otiran Glacial but no loss of overall genetic diversity associated with the cull. Microsatellite data indicated a recent bottleneck for only one population and a range-wide decline in Ne dating back some 300 - 6,000 years ago, a period predating European arrival in NZ. These results suggest that despite a recent human persecution, kea might have experienced a large population decline before stabilizing in numbers prior to human settlement of New Zealand in response to Holocene changes in habitat distribution. Our study therefore highlights the need to understand the respective effects of climate change and human activities on endangered species dynamics when proposing conservation guidelines.

Ancient and contemporary DNA reveal a pre-human decline but no population bottleneck associated with recent human persecution in the kea (Nestor notabilis).

Science.gov (United States)

Dussex, Nicolas; Rawlence, Nicolas J; Robertson, Bruce C

2015-01-01

The impact of population bottlenecks is an important factor to consider when assessing species survival. Population declines can considerably limit the evolutionary potential of species and make them more susceptible to stochastic events. New Zealand has a well documented history of decline of endemic avifauna related to human colonization. Here, we investigate the genetic effects of a recent population decline in the endangered kea (Nestor notabilis). Kea have undergone a long-lasting persecution between the late 1800s to 1970s where an estimated 150,000 kea were culled under a governmental bounty scheme. Kea now number 1,000-5,000 individuals in the wild and it is likely that the recent population decline may have reduced the genetic diversity of the species. Comparison of contemporary (n = 410), historical (n = 15) and fossil samples (n = 4) showed a loss of mitochondrial diversity since the end of the last glaciation (Otiran Glacial) but no loss of overall genetic diversity associated with the cull. Microsatellite data indicated a recent bottleneck for only one population and a range-wide decline in Ne dating back some 300 - 6,000 years ago, a period predating European arrival in NZ. These results suggest that despite a recent human persecution, kea might have experienced a large population decline before stabilizing in numbers prior to human settlement of New Zealand in response to Holocene changes in habitat distribution. Our study therefore highlights the need to understand the respective effects of climate change and human activities on endangered species dynamics when proposing conservation guidelines.

Ancient and Contemporary DNA Reveal a Pre-Human Decline but No Population Bottleneck Associated with Recent Human Persecution in the Kea (Nestor notabilis)

Science.gov (United States)

Dussex, Nicolas; Rawlence, Nicolas J.; Robertson, Bruce C.

2015-01-01

The impact of population bottlenecks is an important factor to consider when assessing species survival. Population declines can considerably limit the evolutionary potential of species and make them more susceptible to stochastic events. New Zealand has a well documented history of decline of endemic avifauna related to human colonization. Here, we investigate the genetic effects of a recent population decline in the endangered kea (Nestor notabilis). Kea have undergone a long-lasting persecution between the late 1800s to 1970s where an estimated 150,000 kea were culled under a governmental bounty scheme. Kea now number 1,000–5,000 individuals in the wild and it is likely that the recent population decline may have reduced the genetic diversity of the species. Comparison of contemporary (n = 410), historical (n = 15) and fossil samples (n = 4) showed a loss of mitochondrial diversity since the end of the last glaciation (Otiran Glacial) but no loss of overall genetic diversity associated with the cull. Microsatellite data indicated a recent bottleneck for only one population and a range-wide decline in Ne dating back some 300 – 6,000 years ago, a period predating European arrival in NZ. These results suggest that despite a recent human persecution, kea might have experienced a large population decline before stabilizing in numbers prior to human settlement of New Zealand in response to Holocene changes in habitat distribution. Our study therefore highlights the need to understand the respective effects of climate change and human activities on endangered species dynamics when proposing conservation guidelines. PMID:25719752

Declining human population but increasing residential development around protected areas in Puerto Rico

Science.gov (United States)

J. Castro-Prieto; S. Martinuzzi; V.C. Radeloff; D.P. Helmers; M. Quiñones; W.A. Gould

2017-01-01

Increasing residential development around protected areas is a major threat for protected areas worldwide, and human population growth is often the most important cause. However, population is decreasing in many regions as a result of socio-economic changes, and it is unclear how residential development around protected areas is affected in these situations. We...

Coral reef degradation is not correlated with local human population density

Science.gov (United States)

Bruno, John F.; Valdivia, Abel

2016-07-01

The global decline of reef-building corals is understood to be due to a combination of local and global stressors. However, many reef scientists assume that local factors predominate and that isolated reefs, far from human activities, are generally healthier and more resilient. Here we show that coral reef degradation is not correlated with human population density. This suggests that local factors such as fishing and pollution are having minimal effects or that their impacts are masked by global drivers such as ocean warming. Our results also suggest that the effects of local and global stressors are antagonistic, rather than synergistic as widely assumed. These findings indicate that local management alone cannot restore coral populations or increase the resilience of reefs to large-scale impacts. They also highlight the truly global reach of anthropogenic warming and the immediate need for drastic and sustained cuts in carbon emissions.

Recent Trends in Local-Scale Marine Biodiversity Reflect Community Structure and Human Impacts.

Science.gov (United States)

Elahi, Robin; O'Connor, Mary I; Byrnes, Jarrett E K; Dunic, Jillian; Eriksson, Britas Klemens; Hensel, Marc J S; Kearns, Patrick J

2015-07-20

The modern biodiversity crisis reflects global extinctions and local introductions. Human activities have dramatically altered rates and scales of processes that regulate biodiversity at local scales. Reconciling the threat of global biodiversity loss with recent evidence of stability at fine spatial scales is a major challenge and requires a nuanced approach to biodiversity change that integrates ecological understanding. With a new dataset of 471 diversity time series spanning from 1962 to 2015 from marine coastal ecosystems, we tested (1) whether biodiversity changed at local scales in recent decades, and (2) whether we can ignore ecological context (e.g., proximate human impacts, trophic level, spatial scale) and still make informative inferences regarding local change. We detected a predominant signal of increasing species richness in coastal systems since 1962 in our dataset, though net species loss was associated with localized effects of anthropogenic impacts. Our geographically extensive dataset is unlikely to be a random sample of marine coastal habitats; impacted sites (3% of our time series) were underrepresented relative to their global presence. These local-scale patterns do not contradict the prospect of accelerating global extinctions but are consistent with local species loss in areas with direct human impacts and increases in diversity due to invasions and range expansions in lower impact areas. Attempts to detect and understand local biodiversity trends are incomplete without information on local human activities and ecological context. Copyright © 2015 Elsevier Ltd. All rights reserved.

Thorium, uranium and plutonium in human tissues of world-wide general population

International Nuclear Information System (INIS)

Singh, N.P.

1990-01-01

The results on the concentrations of thorium, uranium and plutonium in human tissues of world-wide general populations are summarized. The majority of thorium and uranium are accumulated in the skeleton, whereas, plutonium is divided between two major organs: the liver and skeleton. However, there is a wide variation in the fractions of plutonium in the liver and the skeleton of the different populations. (author) 44 refs.; 15 figs

Human rights, ideology and population policies.

Science.gov (United States)

Colombo, B

1977-01-01

Only too often ideology means fanaticism, intolerance, even violence, but the term can be used also to denote sets of preconceptions and presuppositions which act as a stimulus and a guide to scientific innovation, particularly in the field of social science. This sort of insight into the realities of life and the world is a contribution to knowledge and the search for truth, also in the field of human rights. These are taken in the paper as those rights whose infringement constitutes a "vulnus" of the essential characteristics of human beings and those which assume the role of a basic safeguard of them. The meaning of the insistence on the human rights theme in the United Nations system is briefly touched upon, but the main effort is spent in trying to find a firm base for both fundamental rights and duties, shown as strictly and simmetrically linked. Various examples of population policies - broadly defined as governmental interventions influencing demographic variables - are then examined in the light of the basic principles laid down in the said effort. The fields taken up in succession for consideration are international and internal migration, mortality, marriage, fertility in countries at different stages of demographic transition, and growth. Rather than trying an extensive coverage of the whole horizon, a line of critical and deep thought about typical problematic themes is preferred. One of the main conclusions which may be quoted is a statement according to which the problem remains wide open of discovering acceptable ways aiming at a modification of fertility patterns which combine a reduction of the average family size with the maintenance of its variability in order to respect free and responsible individual choices. How important and urgent this task is, is underscored by the observations advanced in the final section of the paper including a meditation on the limits that human sexuality appears to have imposed on itself.

Population Genomics and the Statistical Values of Race:An Interdisciplinary Perspective on the Biological Classification of Human Populations and Implications for Clinical Genetic Epidemiological Research

Directory of Open Access Journals (Sweden)

Koffi N. Maglo

2016-02-01

Full Text Available The biological status and biomedical significance of the concept of race as applied to humans continue to be contentious issues despite the use of advanced statistical and clustering methods to determine continental ancestry. It is thus imperative for researchers to understand the limitations as well as potential uses of the concept of race in biology and biomedicine. This paper deals with the theoretical assumptions behind cluster analysis in human population genomics. Adopting an interdisciplinary approach, it demonstrates that the hypothesis that attributes the clustering of human populations to frictional effects of landform barriers at continental boundaries is empirically incoherent. It then contrasts the scientific status of the cluster and cline constructs in human population genomics, and shows how cluster may be instrumentally produced. It also shows how statistical values of race vindicate Darwin’s argument that race is evolutionarily meaningless. Finally, the paper explains why, due to spatiotemporal parameters, evolutionary forces and socio-cultural factors influencing population structure, continental ancestry may be pragmatically relevant to global and public health genomics. Overall, this work demonstrates that, from a biological systematic and evolutionary taxonomical perspective, human races/continental groups or clusters have no natural meaning or objective biological reality. In fact, the utility of racial categorizations in research and in clinics can be explained by spatiotemporal parameters, socio-cultural factors and evolutionary forces affecting disease causation and treatment response.

Detection and characterization of polymorphisms in XRCC DNA repair genes in human population

International Nuclear Information System (INIS)

Staynova, A.; Hadjidekova, V.; Savov, A.

2004-01-01

Human population is continuously exposed to low levels of ionizing radiation. The main contribution gives the exposure due to medical applications. Nevertheless, most of the damage induced is repaired shortly after exposure by cellular repair systems. The review is focused on the development and application of methods to estimate the character of polymorphisms in repair genes (XRCC1, APE1), involved in single strand breaks repair which is corresponding mainly to the repair of X-ray induced DNA damage. Since, DSB are major factor for chromosomal aberrations formation, the assays described in this review might be useful for the assessment of the radiation risk for human population. (authors)

[Specific features of nesting bird populations in forest-meadow-field landscapes of Meshchovsk Opolye reflect the diversity of their biotope connections].

Science.gov (United States)

Kut'in, S D; Konstantinov, V M

2008-01-01

Studies on specific features of nesting bird populations in patchy landscapes were performed in Meshchovsk Opolye, Kaluga Region, from 1981 to 1990. Indices of similarity between the avifaunas of agricultural fields, lowland bogs, and small-leaved forests markedly differed from parameters of their population density in rank and value. In the series of biotopes differing in the relative amount of woodland, from central areas of small-leaved forests to forest margins and then to forest islands gradually decreasing in size, the birds segregated into two distinct groups, one characteristic of forest margins and large forest islands and the other characteristic of small and very small forest islands. Specific features of bird density distribution in forest-meadow-field landscapes of Meshchovsk Opolye reflected heterogeneity of their populations manifested in diverse connections with nesting biotopes.

A Formidable Task: Reflections on obtaining legal empirical evidence on human trafficking in Canada

Directory of Open Access Journals (Sweden)

Hayli Millar

2017-04-01

Full Text Available This article explores the experiences, challenges and findings of two empirical research studies examining Canada’s legal efforts to combat human trafficking. The authors outline the methodologies of their respective studies and reflect on some of the difficulties they faced in obtaining empirical data on human trafficking court cases and legal proceedings. Ultimately, the authors found that Canadian trafficking case law developments are in their early stages with very few convictions, despite a growing number of police-reported charges. The authors assert it is difficult to assess the efficacy and effects of Canadian anti-trafficking laws and policies due to the institutional and political limitations to collecting legal data in this highly politicised subject area. They conclude with five recommendations to increase the transparency of Canada’s public claims about its anti-trafficking enforcement efforts and call for more empirically-based law reform.

Health, human rights, and the conduct of clinical research within oppressed populations

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Mills Edward J

2007-11-01

Full Text Available Abstract Background Clinical trials evaluating interventions for infectious diseases require enrolling participants that are vulnerable to infection. As clinical trials are conducted in increasingly vulnerable populations, issues of protection of these populations become challenging. In settings where populations are forseeably oppressed, the conduct of research requires considerations that go beyond common ethical concerns and into issues of international human rights law. Discussion Using examples of HIV prevention trials in Thailand, hepatitis-E prevention trials in Nepal and malaria therapeutic trials in Burma (Myanmar, we address the inadequacies of current ethical guidelines when conducting research within oppressed populations. We review existing legislature in the United States and United Kingdom that may be used against foreign investigators if trial hardships exist. We conclude by making considerations for research conducted within oppressed populations.

Epidemiology and health-environment relationship: reflections on environmental change, sustainable development and population health

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Diana M. Montoya

2009-08-01

Full Text Available This essay presents a discussion on current environmental problems and their relationship to the health of populations. The limitations of the model of economic and social development are analyzed focusing on the augmentation of the capital and the industrial production and its negative impact on natural resources, the balance of ecosystems and human vulnerability. The methodological basics and the developments in environmental epidemiological approach are exposed analyzing their main potential application. Finally, options for solutions are formulated linking them to the premises of sustainable development and environmental justice. The responsibility of the academic environment is pointed out in the training of human and scientific resources in the field of environmental epidemiology, as well as the role of the community in terms of environmental awareness and active participation from a point of view that becomes critical, responsible and capable of defining proposals to make part of the solution.

Population-level impact, herd immunity, and elimination after human papillomavirus vaccination

DEFF Research Database (Denmark)

Brisson, Marc; Bénard, Élodie; Drolet, Mélanie

2016-01-01

BackgroundModelling studies have been widely used to inform human papillomavirus (HPV) vaccination policy decisions; however, many models exist and it is not known whether they produce consistent predictions of population-level effectiveness and herd effects. We did a systematic review and meta-a...

Populations of subplate and interstitial neurons in fetal and adult human telencephalon.

Science.gov (United States)

Judaš, Miloš; Sedmak, Goran; Pletikos, Mihovil; Jovanov-Milošević, Nataša

2010-10-01

In the adult human telencephalon, subcortical (gyral) white matter contains a special population of interstitial neurons considered to be surviving descendants of fetal subplate neurons [Kostovic & Rakic (1980) Cytology and the time of origin of interstitial neurons in the white matter in infant and adult human and monkey telencephalon. J Neurocytol9, 219]. We designate this population of cells as superficial (gyral) interstitial neurons and describe their morphology and distribution in the postnatal and adult human cerebrum. Human fetal subplate neurons cannot be regarded as interstitial, because the subplate zone is an essential part of the fetal cortex, the major site of synaptogenesis and the 'waiting' compartment for growing cortical afferents, and contains both projection neurons and interneurons with distinct input-output connectivity. However, although the subplate zone is a transient fetal structure, many subplate neurons survive postnatally as superficial (gyral) interstitial neurons. The fetal white matter is represented by the intermediate zone and well-defined deep periventricular tracts of growing axons, such as the corpus callosum, anterior commissure, internal and external capsule, and the fountainhead of the corona radiata. These tracts gradually occupy the territory of transient fetal subventricular and ventricular zones.The human fetal white matter also contains distinct populations of deep fetal interstitial neurons, which, by virtue of their location, morphology, molecular phenotypes and advanced level of dendritic maturation, remain distinct from subplate neurons and neurons in adjacent structures (e.g. basal ganglia, basal forebrain). We describe the morphological, histochemical (nicotinamide-adenine dinucleotide phosphate-diaphorase) and immunocytochemical (neuron-specific nuclear protein, microtubule-associated protein-2, calbindin, calretinin, neuropeptide Y) features of both deep fetal interstitial neurons and deep (periventricular

Characterization of the human DNA gut virome across populations with different subsistence strategies and geographical origin.

Science.gov (United States)

Rampelli, Simone; Turroni, Silvia; Schnorr, Stephanie L; Soverini, Matteo; Quercia, Sara; Barone, Monica; Castagnetti, Andrea; Biagi, Elena; Gallinella, Giorgio; Brigidi, Patrizia; Candela, Marco

2017-11-01

It is a matter of fact that the human gut microbiome also includes a non-bacterial fraction represented by eukaryotic cells and viruses. To further explore the gut microbiome variation in human populations, here we characterized the human DNA viral community from publicly available gut metagenome data sets from human populations with different geographical origin and lifestyle. In particular, such data sets encompass microbiome information from two western urban societies (USA and Italy), as well as two traditional hunter-gatherer communities (the Hadza from Tanzania and Matses from Peru) and one pre-agricultural tribe (Tunapuco from Peru). Our results allowed for the first taxonomic reconstruction of the complex viral metacommunities within the human gut. The core virome structure included herpesviruses, papillomaviruses, polyomaviruses, adenoviruses and anelloviruses. Using Random Forests and a co-occurrence analysis approach, we identified the viruses that distinguished populations according to their geographical origin and/or lifestyle. This paves the way for new research aimed at investigating the biological role of the gut virome in human physiology, and the importance of our viral counterpart in the microbiome-host co-evolutionary process. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

CD146/MCAM defines functionality of human bone marrow stromal stem cell populations

DEFF Research Database (Denmark)

Harkness, Linda; Zaher, Walid; Ditzel, Nicholas

2016-01-01

BACKGROUND: Identification of surface markers for prospective isolation of functionally homogenous populations of human skeletal (stromal, mesenchymal) stem cells (hMSCs) is highly relevant for cell therapy protocols. Thus, we examined the possible use of CD146 to subtype a heterogeneous hMSC...... population. METHODS: Using flow cytometry and cell sorting, we isolated two distinct hMSC-CD146(+) and hMSC-CD146(-) cell populations from the telomerized human bone marrow-derived stromal cell line (hMSC-TERT). Cells were examined for differences in their size, shape and texture by using high...... and adipocytes on the basis of gene expression and protein production of lineage-specific markers. In vivo, hMSC-CD146(+) and hMSC-CD146(-) cells formed bone and bone marrow organ when implanted subcutaneously in immune-deficient mice. Bone was enriched in hMSC-CD146(-) cells (12.6 % versus 8.1 %) and bone...

Prediction of human population responses to toxic compounds by a collaborative competition.

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Eduati, Federica; Mangravite, Lara M; Wang, Tao; Tang, Hao; Bare, J Christopher; Huang, Ruili; Norman, Thea; Kellen, Mike; Menden, Michael P; Yang, Jichen; Zhan, Xiaowei; Zhong, Rui; Xiao, Guanghua; Xia, Menghang; Abdo, Nour; Kosyk, Oksana; Friend, Stephen; Dearry, Allen; Simeonov, Anton; Tice, Raymond R; Rusyn, Ivan; Wright, Fred A; Stolovitzky, Gustavo; Xie, Yang; Saez-Rodriguez, Julio

2015-09-01

The ability to computationally predict the effects of toxic compounds on humans could help address the deficiencies of current chemical safety testing. Here, we report the results from a community-based DREAM challenge to predict toxicities of environmental compounds with potential adverse health effects for human populations. We measured the cytotoxicity of 156 compounds in 884 lymphoblastoid cell lines for which genotype and transcriptional data are available as part of the Tox21 1000 Genomes Project. The challenge participants developed algorithms to predict interindividual variability of toxic response from genomic profiles and population-level cytotoxicity data from structural attributes of the compounds. 179 submitted predictions were evaluated against an experimental data set to which participants were blinded. Individual cytotoxicity predictions were better than random, with modest correlations (Pearson's r < 0.28), consistent with complex trait genomic prediction. In contrast, predictions of population-level response to different compounds were higher (r < 0.66). The results highlight the possibility of predicting health risks associated with unknown compounds, although risk estimation accuracy remains suboptimal.

The dynamic influence of human resources on evidence-based intervention sustainability and population outcomes: an agent-based modeling approach.

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McKay, Virginia R; Hoffer, Lee D; Combs, Todd B; Margaret Dolcini, M

2018-06-05

Sustaining evidence-based interventions (EBIs) is an ongoing challenge for dissemination and implementation science in public health and social services. Characterizing the relationship among human resource capacity within an agency and subsequent population outcomes is an important step to improving our understanding of how EBIs are sustained. Although human resource capacity and population outcomes are theoretically related, examining them over time within real-world experiments is difficult. Simulation approaches, especially agent-based models, offer advantages that complement existing methods. We used an agent-based model to examine the relationships among human resources, EBI delivery, and population outcomes by simulating provision of an EBI through a hypothetical agency and its staff. We used data from existing studies examining a widely implemented HIV prevention intervention to inform simulation design, calibration, and validity. Once we developed a baseline model, we used the model as a simulated laboratory by systematically varying three human resource variables: the number of staff positions, the staff turnover rate, and timing in training. We tracked the subsequent influence on EBI delivery and the level of population risk over time to describe the overall and dynamic relationships among these variables. Higher overall levels of human resource capacity at an agency (more positions) led to more extensive EBI delivery over time and lowered population risk earlier in time. In simulations representing the typical human resource investments, substantial influences on population risk were visible after approximately 2 years and peaked around 4 years. Human resources, especially staff positions, have an important impact on EBI sustainability and ultimately population health. A minimum level of human resources based on the context (e.g., size of the initial population and characteristics of the EBI) is likely needed for an EBI to have a meaningful impact on

Specific features of diffuse reflection of human face skin for laser and non-laser sources of visible and near-IR light

International Nuclear Information System (INIS)

Dolotov, L E; Sinichkin, Yu P; Tuchin, Valerii V; Al'tshuler, G B; Yaroslavskii, I V

2011-01-01

The specific features of diffuse reflection from different areas of human face skin for laser and non-laser sources of visible and near-IR light have been investigated to localise the closed-eye (eyelid) region. In the visible spectral range the reflection from the eyelid skin surface can be differentiated by measuring the slope of the spectral dependence of the effective optical density of skin in the wavelength range from 650 to 700nm. In the near-IR spectral range the reflectances of the skin surface at certain wavelengths, normalised to the forehead skin reflectance, can be used as a criterion for differentiating the eyelid skin. In this case, a maximum discrimination is obtained when measuring the skin reflectances at laser wavelengths of 1310 and 1470nm, which correspond to the spectral ranges of maximum and minimum water absorption. (optical technologies in biophysics and medicine)

HLA DNA sequence variation among human populations: molecular signatures of demographic and selective events.

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Stéphane Buhler

2011-02-01

Full Text Available Molecular differences between HLA alleles vary up to 57 nucleotides within the peptide binding coding region of human Major Histocompatibility Complex (MHC genes, but it is still unclear whether this variation results from a stochastic process or from selective constraints related to functional differences among HLA molecules. Although HLA alleles are generally treated as equidistant molecular units in population genetic studies, DNA sequence diversity among populations is also crucial to interpret the observed HLA polymorphism. In this study, we used a large dataset of 2,062 DNA sequences defined for the different HLA alleles to analyze nucleotide diversity of seven HLA genes in 23,500 individuals of about 200 populations spread worldwide. We first analyzed the HLA molecular structure and diversity of these populations in relation to geographic variation and we further investigated possible departures from selective neutrality through Tajima's tests and mismatch distributions. All results were compared to those obtained by classical approaches applied to HLA allele frequencies.Our study shows that the global patterns of HLA nucleotide diversity among populations are significantly correlated to geography, although in some specific cases the molecular information reveals unexpected genetic relationships. At all loci except HLA-DPB1, populations have accumulated a high proportion of very divergent alleles, suggesting an advantage of heterozygotes expressing molecularly distant HLA molecules (asymmetric overdominant selection model. However, both different intensities of selection and unequal levels of gene conversion may explain the heterogeneous mismatch distributions observed among the loci. Also, distinctive patterns of sequence divergence observed at the HLA-DPB1 locus suggest current neutrality but old selective pressures on this gene. We conclude that HLA DNA sequences advantageously complement HLA allele frequencies as a source of data used

Considerations for a Human Rights Impact Assessment of a Population Wide Treatment for HIV Prevention Intervention.

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Hanefeld, Johanna; Bond, Virginia; Seeley, Janet; Lees, Shelley; Desmond, Nicola

2015-12-01

Increasing attention is being paid to the potential of anti-retroviral treatment (ART) for HIV prevention. The possibility of eliminating HIV from a population through a universal test and treat intervention, where all people within a population are tested for HIV and all positive people immediately initiated on ART, as part of a wider prevention intervention, was first proposed in 2009. Several clinical trials testing this idea are now in inception phase. An intervention which relies on universally testing the entire population for HIV will pose challenges to human rights, including obtaining genuine consent to testing and treatment. It also requires a context in which people can live free from fear of stigma, discrimination and violence, and can access services they require. These challenges are distinct from the field of medical ethics which has traditionally governed clinical trials and focuses primarily on patient researcher relationship. This paper sets out the potential impact of a population wide treatment as prevention intervention on human rights. It identifies five human right principles of particular relevance: participation, accountability, the right to health, non-discrimination and equality, and consent and confidentiality. The paper proposes that explicit attention to human rights can strengthen a treatment as prevention intervention, contribute to mediating likely health systems challenges and offer insights on how to reach all sections of the population. © 2013 John Wiley & Sons Ltd.

Directional and balancing selection in human beta-defensins.

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Hollox, Edward J; Armour, John A L

2008-04-16

In primates, infection is an important force driving gene evolution, and this is reflected in the importance of infectious disease in human morbidity today. The beta-defensins are key components of the innate immune system, with antimicrobial and cell signalling roles, but also reproductive functions. Here we examine evolution of beta-defensins in catarrhine primates and variation within different human populations. We show that five beta-defensin genes that do not show copy number variation in humans show evidence of positive selection in catarrhine primates, and identify specific codons that have been under selective pressure. Direct haplotyping of DEFB127 in humans suggests long-term balancing selection: there are two highly diverged haplotype clades carrying different variants of a codon that, in primates, is positively selected. For DEFB132, we show that extensive diversity, including a four-state amino acid polymorphism (valine, isoleucine, alanine and threonine at position 93), is present in hunter-gatherer populations, both African and non-African, but not found in samples from agricultural populations. Some, but not all, beta-defensin genes show positive selection in catarrhine primates. There is suggestive evidence of different selective pressures on these genes in humans, but the nature of the selective pressure remains unclear and is likely to differ between populations.

Human migration is important in the international spread of exotic Salmonella serovars in animal and human populations.

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Iveson, J B; Bradshaw, S D; How, R A; Smith, D W

2014-11-01

The exposure of indigenous humans and native fauna in Australia and the Wallacea zoogeographical region of Indonesia to exotic Salmonella serovars commenced during the colonial period and has accelerated with urbanization and international travel. In this study, the distribution and prevalence of exotic Salmonella serovars are mapped to assess the extent to which introduced infections are invading native wildlife in areas of high natural biodiversity under threat from expanding human activity. The major exotic Salmonella serovars, Bovismorbificans, Derby, Javiana, Newport, Panama, Saintpaul and Typhimurium, isolated from wildlife on populated coastal islands in southern temperate areas of Western Australia, were mostly absent from reptiles and native mammals in less populated tropical areas of the state. They were also not recorded on the uninhabited Mitchell Plateau or islands of the Bonaparte Archipelago, adjacent to south-eastern Indonesia. Exotic serovars were, however, isolated in wildlife on 14/17 islands sampled in the Wallacea region of Indonesia and several islands off the west coast of Perth. Increases in international tourism, involving islands such as Bali, have resulted in the isolation of a high proportion of exotic serovar infections suggesting that densely populated island resorts in the Asian region are acting as staging posts for the interchange of Salmonella infections between tropical and temperate regions.

Key Inflammatory Processes in Human NASH Are Reflected in Ldlr−/−.Leiden Mice: A Translational Gene Profiling Study

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Morrison, Martine C.; Kleemann, Robert; van Koppen, Arianne; Hanemaaijer, Roeland; Verschuren, Lars

2018-01-01

Introduction: It is generally accepted that metabolic inflammation in the liver is an important driver of disease progression in NASH and associated matrix remodeling/fibrosis. However, the exact molecular inflammatory mechanisms are poorly defined in human studies. Investigation of key pathogenic mechanisms requires the use of pre-clinical models, for instance for time-resolved studies. Such models must reflect molecular disease processes of importance in patients. Herein we characterized inflammation in NASH patients on the molecular level by transcriptomics and investigated whether key human disease pathways can be recapitulated experimentally in Ldlr−/−.Leiden mice, an established pre-clinical model of NASH. Methods: Human molecular inflammatory processes were defined using a publicly available NASH gene expression profiling dataset (GSE48452) allowing the comparison of biopsy-confirmed NASH patients with normal controls. Gene profiling data from high-fat diet (HFD)-fed Ldlr−/−.Leiden mice (GSE109345) were used for assessment of the translational value of these mice. Results: In human NASH livers, we observed regulation of 65 canonical pathways of which the majority was involved in inflammation (32%), lipid metabolism (16%), and extracellular matrix/remodeling (12%). A similar distribution of pathways across these categories, inflammation (36%), lipid metabolism (24%) and extracellular matrix/remodeling (8%) was observed in HFD-fed Ldlr−/−.Leiden mice. Detailed evaluation of these pathways revealed that a substantial proportion (11 out of 13) of human NASH inflammatory pathways was recapitulated in Ldlr−/−.Leiden mice. Furthermore, the activation state of identified master regulators of inflammation (i.e., specific transcription factors, cytokines, and growth factors) in human NASH was largely reflected in Ldlr−/−.Leiden mice, further substantiating its translational value. Conclusion: Human NASH is characterized by upregulation of specific

Nuclear genetic diversity in human lice (Pediculus humanus reveals continental differences and high inbreeding among worldwide populations.

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Marina S Ascunce

Full Text Available Understanding the evolution of parasites is important to both basic and applied evolutionary biology. Knowledge of the genetic structure of parasite populations is critical for our ability to predict how an infection can spread through a host population and for the design of effective control methods. However, very little is known about the genetic structure of most human parasites, including the human louse (Pediculus humanus. This species is composed of two ecotypes: the head louse (Pediculus humanus capitis De Geer, and the clothing (body louse (Pediculus humanus humanus Linnaeus. Hundreds of millions of head louse infestations affect children every year, and this number is on the rise, in part because of increased resistance to insecticides. Clothing lice affect mostly homeless and refugee-camp populations and although they are less prevalent than head lice, the medical consequences are more severe because they vector deadly bacterial pathogens. In this study we present the first assessment of the genetic structure of human louse populations by analyzing the nuclear genetic variation at 15 newly developed microsatellite loci in 93 human lice from 11 sites in four world regions. Both ecotypes showed heterozygote deficits relative to Hardy-Weinberg equilibrium and high inbreeding values, an expected pattern given their parasitic life history. Bayesian clustering analyses assigned lice to four distinct genetic clusters that were geographically structured. The low levels of gene flow among louse populations suggested that the evolution of insecticide resistance in lice would most likely be affected by local selection pressures, underscoring the importance of tailoring control strategies to population-specific genetic makeup and evolutionary history. Our panel of microsatellite markers provides powerful data to investigate not only ecological and evolutionary processes in lice, but also those in their human hosts because of the long

Y Chromosome analysis of prehistoric human populations in the West Liao River Valley, Northeast China.

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Cui, Yinqiu; Li, Hongjie; Ning, Chao; Zhang, Ye; Chen, Lu; Zhao, Xin; Hagelberg, Erika; Zhou, Hui

2013-09-30

The West Liao River valley in Northeast China is an ecologically diverse region, populated in prehistory by human populations with a wide range of cultures and modes of subsistence. To help understand the human evolutionary history of this region, we performed Y chromosome analyses on ancient human remains from archaeological sites ranging in age from 6500 to 2700 BP. 47 of the 70 individuals provided reproducible results. They were assigned into five different Y sub-haplogroups using diagnostic single nucleotide polymorphisms, namely N1 (xN1a, N1c), N1c, C/C3e, O3a (O3a3) and O3a3c. We also used 17 Y short tandem repeat loci in the non-recombining portion of the Y chromosome. There appears to be significant genetic differences between populations of the West Liao River valley and adjacent cultural complexes in the prehistoric period, and these prehistoric populations were shown to carry similar haplotypes as present-day Northeast Asians, but at markedly different frequencies. Our results suggest that the prehistoric cultural transitions were associated with immigration from the Yellow River valley and the northern steppe into the West Liao River valley. They reveal the temporal continuity of Y chromosome lineages in populations of the West Liao River valley over 5000 years, with a concurrent increase in lineage diversity caused by an influx of immigrants from other populations.

Reflections on Ethics and Humanity in Pediatric Neurology: the Value of Recognizing Ethical Issues in Common Clinical Practice.

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Ronen, Gabriel M; Rosenbaum, Peter L

2017-05-01

Our goals in this reflection are to (i) identify the ethical dimensions inherent in any clinical encounter and (ii) bring to the forefront of our pediatric neurology practice the myriad of opportunities to explore and learn from these ethical questions. We highlight specifically Beauchamp and Childress's principles of biomedical ethics. We use the terms ethics in common clinical practice and an ethical lens to remind people of the ubiquity of ethical situations and the usefulness of using existing ethical principles to analyze and resolve difficult situations in clinical practice. We start with a few common situations with which many of us tend to struggle. We describe what we understand as ethics and how and why developments in technology, novel potential interventions, policies, and societal perspectives challenge us to think about and debate ethical issues. Individual patients are not a singular population; each patient has their own unique life situations, culture, goals, and expectations that need to be considered with a good dose of humanity and humility. We believe that using an ethical lens-by which we mean making an explicit effort to identify and consider these issues openly-will help us to achieve this goal in practice, education, and research.

Human capital of the child population and its selected determinants: Case study of Lviv city, Ukraine

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Pantyley Viktoriya

2017-09-01

Full Text Available In conditions of modern economic and political destabilisation in Ukraine, human capital of the child population is considered as the most reliable indicator of socioeconomic development of the country and its regions. The primary goal of the study is the analysis of health status as the main element of human capital among the child population aged 0-14, and external and family environmental factors influencing this population group in the city of Lviv (in the light of available statistics and materials of the author’s own sociological research. Research results show a potential crisis of human capital among the child population in Lviv city. Results of own field research show a statistically important correlation between the willingness of parents to have more children and the following independent variables: number of members in the household, and the household’s income. The state of health among the child population showed a significant correlation between the following variables: household’s income, life satisfaction among parents, availability of healthcare in the place of residence, financial affordability of healthcare, physical activity among children, influence of noise and unpleasant scents.

Demography and dog-human relationships of the dog population in Zimbabwean communal lands.

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Butler, J R; Bingham, J

2000-10-14

Dogs are Zimbabwe's primary vector for rabies, and the majority live in communal lands (traditional agropastoralist rural areas). In 1994, a household questionnaire survey was conducted to provide baseline data on the demography and dog-human relationships of the dogs in the communal lands. The survey showed that all the dogs were owned, and there was no evidence of a feral population. They were unrestricted and semi-dependent on people. The numbers of dogs per capita varied little in each communal land, resulting in higher dog densities in communal lands with higher human densities, and indicating that people were not intolerant of dogs at higher densities. The population turnover was rapid: the life expectancy of the dogs was 1.1 years, the mean age 2.0 years, and 71.8 per cent died in their first year. The population was heavily skewed towards juveniles, with 40.8 per cent aged less than 12 months. Despite the high juvenile mortality, the population was growing by 6.52 per cent per annum. It was estimated that in 1994 there were 1.36 million dogs in communal lands.

Reflections on human presence in space

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Arnould, Jacques

2001-08-01

Humankind's exploration of Space has until now been understood as analagous to that of planet Earth: sending out crews to far-off, unknown lands in the hope of finding supplies of food, water or energy along with shelter and living-space. But Space is turning out to be much less hospitable than our earthly milieu in terms of resources as well as energy costs. It seems appropriate to ask what level of adaptation is needed for humans to travel and live in the cosmos, and to assess if the next logical step should necessarily be a programme of conquest analagous to that of the Moon — for example, towards Mars. Should we not rather be making more use of Earth's immediate neighbourhood, namely the sphere of a million of kilometres we call "Greater Earth"? In the same way, it is appropriate to ask questions about the conception of human beings which will from now on sustain the conquest of Space. The astronaut of the last forty years is the direct heir of the explorers of Ancient and Modern times; now, through the influence of science and technology, humanity has been put "into motion" not only geographically, but also in its most essential foundations: culture, psychology, philosophy. If the development of telepresence technology now gives us the ability to talk about a "Greater Human Being", it is chiefly through freedom of choice for oneself, for humanity and even for Earth.

The effect of ultraviolet light on arrested human diploid cell populations

International Nuclear Information System (INIS)

Kantor, G.J.; Warner, C.; Hull, D.R.

1977-01-01

The results of the experiments to determine an effect of UV (254 nm) on human diploid fibroblasts (HDF) arrested with respect to division by using 0.5% fetal calf serum in the culture medium are reported. A fraction of cells from irradiated arrested populations, maintained in the arrested state post-irradiation, was lost from the populations. The extent of cell loss was fluence-dependent and cell strain specific. A Xeroderma pigmentosum cell strain was more sensitive to UV than were normal HDF. No difference in sensitivity were observed when arrested populations established from normal HDF populations of various in vitro ages were used. The length of the pre-irradiation arrested period affected the sensitivity of normal HDF, which appeared more resistant at longer arrested periods, but not the sensitivity of arrested Xeroderma populations. These results suggest that DNA repair processes play a role in maintaining irradiated cells in the arrested state. The suggestion is made that the lethal event caused by UV is an effect on transcription leading to an inhibition of required protein synthesis. (author)

Genetic diversity and natural selection footprints of the glycine amidinotransferase gene in various human populations.

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Khan, Asifullah; Tian, Lei; Zhang, Chao; Yuan, Kai; Xu, Shuhua

2016-01-05

The glycine amidinotransferase gene (GATM) plays a vital role in energy metabolism in muscle tissues and is associated with multiple clinically important phenotypes. However, the genetic diversity of the GATM gene remains poorly understood within and between human populations. Here we analyzed the 1,000 Genomes Project data through population genetics approaches and observed significant genetic diversity across the GATM gene among various continental human populations. We observed considerable variations in GATM allele frequencies and haplotype composition among different populations. Substantial genetic differences were observed between East Asian and European populations (FST = 0.56). In addition, the frequency of a distinct major GATM haplotype in these groups was congruent with population-wide diversity at this locus. Furthermore, we identified GATM as the top differentiated gene compared to the other statin drug response-associated genes. Composite multiple analyses identified signatures of positive selection at the GATM locus, which was estimated to have occurred around 850 generations ago in European populations. As GATM catalyzes the key step of creatine biosynthesis involved in energy metabolism, we speculate that the European prehistorical demographic transition from hunter-gatherer to farming cultures was the driving force of selection that fulfilled creatine-based metabolic requirement of the populations.

Distance to human populations influences epidemiology of respiratory disease in desert tortoises

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Berry, Kristin H.; Ashley A. Coble (formerly Emerson), no longer USGS; Yee, Julie L.; Mack, Jeremy S.; Perry, William M.; Anderson, Kemp M.; Brown, Mary B.

2014-01-01

We explored variables likely to affect health of Agassiz's desert tortoises (Gopherus agassizii) in a 1,183-km2 study area in the central Mojave Desert of California between 2005 and 2008. We evaluated 1,004 tortoises for prevalence and spatial distribution of 2 pathogens, Mycoplasma agassizii and M. testudineum, that cause upper respiratory tract disease. We defined tortoises as test-positive if they were positive by culture and/or DNA identification or positive or suspect for specific antibody for either of the two pathogens. We used covariates of habitat (vegetation, elevation, slope, and aspect), tortoise size and sex, distance from another test-positive tortoise, and anthropogenic variables (distances to roads, agricultural areas, playas, urban areas, and centroids of human-populated census blocks). We used both logistic regression models and regression trees to evaluate the 2 species of Mycoplasma separately. The prevalence of test-positive tortoises was low: 1.49% (15/1,004) for M. agassizii and 2.89% (29/1,004) for M. testudineum. The spatial distributions of test-positive tortoises for the 2 Mycoplasma species showed little overlap; only 2 tortoises were test-positive for both diseases. However, the spatial distributions did not differ statistically between the 2 species. We consistently found higher prevalence of test-positive tortoises with shorter distances to centroids of human-populated census blocks. The relationship between distance to human-populated census blocks and tortoises that are test-positive for M. agassizii and potentially M. testudineum may be related to release or escape of captive tortoises because the prevalence of M. agassizii in captive tortoises is high. Our findings have application to other species of chelonians where both domestic captive and wild populations exist. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

A Quantitative Comparison of the Similarity between Genes and Geography in Worldwide Human Populations

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Wang, Chaolong; Zöllner, Sebastian; Rosenberg, Noah A.

2012-01-01

Multivariate statistical techniques such as principal components analysis (PCA) and multidimensional scaling (MDS) have been widely used to summarize the structure of human genetic variation, often in easily visualized two-dimensional maps. Many recent studies have reported similarity between geographic maps of population locations and MDS or PCA maps of genetic variation inferred from single-nucleotide polymorphisms (SNPs). However, this similarity has been evident primarily in a qualitative sense; and, because different multivariate techniques and marker sets have been used in different studies, it has not been possible to formally compare genetic variation datasets in terms of their levels of similarity with geography. In this study, using genome-wide SNP data from 128 populations worldwide, we perform a systematic analysis to quantitatively evaluate the similarity of genes and geography in different geographic regions. For each of a series of regions, we apply a Procrustes analysis approach to find an optimal transformation that maximizes the similarity between PCA maps of genetic variation and geographic maps of population locations. We consider examples in Europe, Sub-Saharan Africa, Asia, East Asia, and Central/South Asia, as well as in a worldwide sample, finding that significant similarity between genes and geography exists in general at different geographic levels. The similarity is highest in our examples for Asia and, once highly distinctive populations have been removed, Sub-Saharan Africa. Our results provide a quantitative assessment of the geographic structure of human genetic variation worldwide, supporting the view that geography plays a strong role in giving rise to human population structure. PMID:22927824

A quantitative comparison of the similarity between genes and geography in worldwide human populations.

Science.gov (United States)

Wang, Chaolong; Zöllner, Sebastian; Rosenberg, Noah A

2012-08-01

Multivariate statistical techniques such as principal components analysis (PCA) and multidimensional scaling (MDS) have been widely used to summarize the structure of human genetic variation, often in easily visualized two-dimensional maps. Many recent studies have reported similarity between geographic maps of population locations and MDS or PCA maps of genetic variation inferred from single-nucleotide polymorphisms (SNPs). However, this similarity has been evident primarily in a qualitative sense; and, because different multivariate techniques and marker sets have been used in different studies, it has not been possible to formally compare genetic variation datasets in terms of their levels of similarity with geography. In this study, using genome-wide SNP data from 128 populations worldwide, we perform a systematic analysis to quantitatively evaluate the similarity of genes and geography in different geographic regions. For each of a series of regions, we apply a Procrustes analysis approach to find an optimal transformation that maximizes the similarity between PCA maps of genetic variation and geographic maps of population locations. We consider examples in Europe, Sub-Saharan Africa, Asia, East Asia, and Central/South Asia, as well as in a worldwide sample, finding that significant similarity between genes and geography exists in general at different geographic levels. The similarity is highest in our examples for Asia and, once highly distinctive populations have been removed, Sub-Saharan Africa. Our results provide a quantitative assessment of the geographic structure of human genetic variation worldwide, supporting the view that geography plays a strong role in giving rise to human population structure.

Final report on effects of environmental radiation of Kori nuclear power plant on human population

International Nuclear Information System (INIS)

Kim, Y.J.; Kim, J.B.; Chung, K.H.; Lee, K.S.; Kim, S.R.; Yang, S.Y.

1980-01-01

In order to clarify and protect the effects of environmental radiation according to the operation of Kori nuclear power plant on the human population, the base line survey for the human monitoring, human life habits, expected individual exposure dose, frequencies of chromosomal aberration, gene frequencies and karyotypes in amphibia, fauna, and radiation sensitivities in microorganisms which have been living around the power plant site were carried out. Kilchonri population which took for the human monitoring lie within a 2 km distance from the power plant site. Human monitoring, house and food characteristics, individual experience of x-ray exposures, human chromosome analysis and fauna were surveyed and expressed in numerical tables. Chromosome number obtained from the amphibia which were collected around the power plant area was as follows: Kaloula borealis 2N=30, Rana amurensis 2N=26, Rana dybouskii 2N=24, Rana rugosa 2N=26, Rana nigromaculata 2N=26, Rana plancyi 2N=26, Bombina orientalis 2N=24, Hyla arborea 2N=24, Bufo stejnegeri 2N=22, Bufo bufo 2N=22. (author)

Metabolic profiling detects early effects of environmental and lifestyle exposure to cadmium in a human population

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Ellis James K

2012-06-01

Full Text Available Abstract Background The 'exposome' represents the accumulation of all environmental exposures across a lifetime. Top-down strategies are required to assess something this comprehensive, and could transform our understanding of how environmental factors affect human health. Metabolic profiling (metabonomics/metabolomics defines an individual's metabolic phenotype, which is influenced by genotype, diet, lifestyle, health and xenobiotic exposure, and could also reveal intermediate biomarkers for disease risk that reflect adaptive response to exposure. We investigated changes in metabolism in volunteers living near a point source of environmental pollution: a closed zinc smelter with associated elevated levels of environmental cadmium. Methods High-resolution 1H NMR spectroscopy (metabonomics was used to acquire urinary metabolic profiles from 178 human volunteers. The spectral data were subjected to multivariate and univariate analysis to identify metabolites that were correlated with lifestyle or biological factors. Urinary levels of 8-oxo-deoxyguanosine were also measured, using mass spectrometry, as a marker of systemic oxidative stress. Results Six urinary metabolites, either associated with mitochondrial metabolism (citrate, 3-hydroxyisovalerate, 4-deoxy-erythronic acid or one-carbon metabolism (dimethylglycine, creatinine, creatine, were associated with cadmium exposure. In particular, citrate levels retained a significant correlation to urinary cadmium and smoking status after controlling for age and sex. Oxidative stress (as determined by urinary 8-oxo-deoxyguanosine levels was elevated in individuals with high cadmium exposure, supporting the hypothesis that heavy metal accumulation was causing mitochondrial dysfunction. Conclusions This study shows evidence that an NMR-based metabolic profiling study in an uncontrolled human population is capable of identifying intermediate biomarkers of response to toxicants at true environmental

Identification and clonal characterisation of a progenitor cell sub-population in normal human articular cartilage.

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Rebecca Williams

Full Text Available BACKGROUND: Articular cartilage displays a poor repair capacity. The aim of cell-based therapies for cartilage defects is to repair damaged joint surfaces with a functional replacement tissue. Currently, chondrocytes removed from a healthy region of the cartilage are used but they are unable to retain their phenotype in expanded culture. The resulting repair tissue is fibrocartilaginous rather than hyaline, potentially compromising long-term repair. Mesenchymal stem cells, particularly bone marrow stromal cells (BMSC, are of interest for cartilage repair due to their inherent replicative potential. However, chondrocyte differentiated BMSCs display an endochondral phenotype, that is, can terminally differentiate and form a calcified matrix, leading to failure in long-term defect repair. Here, we investigate the isolation and characterisation of a human cartilage progenitor population that is resident within permanent adult articular cartilage. METHODS AND FINDINGS: Human articular cartilage samples were digested and clonal populations isolated using a differential adhesion assay to fibronectin. Clonal cell lines were expanded in growth media to high population doublings and karyotype analysis performed. We present data to show that this cell population demonstrates a restricted differential potential during chondrogenic induction in a 3D pellet culture system. Furthermore, evidence of high telomerase activity and maintenance of telomere length, characteristic of a mesenchymal stem cell population, were observed in this clonal cell population. Lastly, as proof of principle, we carried out a pilot repair study in a goat in vivo model demonstrating the ability of goat cartilage progenitors to form a cartilage-like repair tissue in a chondral defect. CONCLUSIONS: In conclusion, we propose that we have identified and characterised a novel cartilage progenitor population resident in human articular cartilage which will greatly benefit future cell

The Philippine Population Program strategic plan (1981-1985).

Science.gov (United States)

1980-01-01

The challenge of the population problem is to effectively mobilize the country's population for productive activity. Rather than simply concern with controlling numbers, emphasis is on human resource management, the structure of employment, labor productivity and income distribution. The long-term Philippine Development Plans reflect recognition of the dynamic interaction between fertility, productivity and welfare. Objectives of the 5-Year Philippine Development Plan 1978-1982, the 10-Year Plan 1978-1987, and the Long-Term Plan to year 2000 integrate population concerns and socioeconomic goals. These objectives include the following: promotion of social development and social justice; attainment of self-sufficiency in food and greater self-reliance in energy; increased development of lagging regions, especially rural areas; improvements of habitat through the development of human settlements and proper management of the environment; and maintenance of population growth at levels conducive to national welfare. Some population concerns that are directly relevant to welfare (in addition to those related to productivity) are distribution patterns of social goods and services, access to services by sectors of the population, and buying power of families. As a total population policy should establish closer linkages, operationally, between the demographic aspects and the productivity and welfare aspects of development, the mission of the National Population Program encompasses 3 areas: fertility; productivity; and welfare. Strategic policies include the following: abortion is unacceptable as a contraceptive method; the population program shall be non-coercive; and the program shall view individual and family welfare in the context and as the main objective of national socioeconomic programs.

Analysis of hemodynamics in human skin using photothermal radiometry and diffuse reflectance spectroscopy

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Verdel, Nina; Marin, Ana; Vidovič, Luka; Milanič, Matija; Majaron, Boris

2017-07-01

We present a novel methodology for quantitative analysis of hemodynamics in human skin in vivo. Our approach combines pulsed photothermal radiometry (i.e., time-resolved measurements of midinfrared emission from sample surface after exposure to a short light pulse) and diffuse reflectance spectroscopy in visible part of the spectrum. Experimental data are fitted with predictions of a numerical model of light transport in a four-layer skin model (i.e., inverse Monte Carlo), which allows assessment of the layer thicknesses, chromophore contents (e.g., melanin, oxy- and deoxy-hemoglobin), as well as scattering properties. The performance is tested in comparison analysis of healthy skin before and during application of a blood pressure cuff (at 200 mm Hg) for 5 minutes.

Parameterization using Fourier series expansion of the diffuse reflectance of human skin to vary the concentration of the melanocytes

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Narea, J. Freddy; Muñoz, Aarón A.; Castro, Jorge; Muñoz, Rafael A.; Villalba, Caroleny E.; Martinez, María. F.; Bravo, Kelly D.

2013-11-01

Human skin has been studied in numerous investigations, given the interest in knowing information about physiology, morphology and chemical composition. These parameters can be determined using non invasively optical techniques in vivo, such as the diffuse reflectance spectroscopy. The human skin color is determined by many factors, but primarily by the amount and distribution of the pigment melanin. The melanin is produced by the melanocytes in the basal layer of the epidermis. This research characterize the spectral response of the human skin using the coefficients of Fourier series expansion. Simulating the radiative transfer equation for the Monte Carlo method to vary the concentration of the melanocytes (fme) in a simplified model of human skin. It fits relating the Fourier series coefficient a0 with fme. Therefore it is possible to recover the skin biophysical parameter.

History of Smallpox and Its Spread in Human Populations.

Science.gov (United States)

Thèves, Catherine; Crubézy, Eric; Biagini, Philippe

2016-08-01

Smallpox is considered among the most devastating of human diseases. Its spread in populations, initiated for thousands of years following a probable transmission from an animal host, was concomitant with movements of people across regions and continents, trade and wars. Literature permitted to retrace the occurrence of epidemics from ancient times to recent human history, smallpox having affected all levels of past society including famous monarchs. The disease was officially declared eradicated in 1979 following intensive vaccination campaigns.Paleomicrobiology dedicated to variola virus is restricted to few studies, most unsuccessful, involving ancient material. Only one recent approach allowed the identification of viral DNA fragments from lung tissue of a 300-year-old body excavated from permafrost in Eastern Siberia; phylogenetic analysis revealed that this ancient strain was distinct from those described during the 20th century.

Influence of physical activity in length of life of the human population in the context of changes

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Ahmetović Zlatko

2014-01-01

Full Text Available Since the middle of the last century, the human population has increased exponentially. This trend is evident today. Human population has, for more than half a century been undergoing the period of its intensive development, increasing in number and the average length of life, creating the impression of a better life standard. Looking at the man as a bio-psycho-social being and the interactions it ones through the human population growth is brought in connection with its impact on the environment. In such an environment, one does not only face infectious diseases, but also the misery and poverty in developing countries and massive noninfectious diseases, in developed countries. These facts introduce evidence about the possible effects of physical activity as to prevent the consequences of mass noninfectious diseases, as well as to strengthen the competence of people in general. Therefore, in a holistic, synergic concept of interpretation of human life, it is significant to include biological indicators that have an impact on the growth of the world population and may be associated with the kinesiology. Quantitative indicators of the trend of human development on this planet are the basic research unit observed in this paper. At the same time, the subjects of observation are also other indicators that can be causally linked to the development of the human population and are especially valuable evidence of the contribution of physical activity to the human development. The data that is associated with the theoretical considerations and the results of various statistics are presented based on the rules of ex-post-facto analysis. It is concluded that the value of physical activity has long had to have the equal status with one's chances of being better prepared for life on this planet ontogenetically and phylogenetically, and for the life conditions that will become even more extreme and that increasing older humans will face.

Useful model organisms, indicators, or both? Ground beetles (Coleoptera, Carabidae) reflecting environmental conditions.

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Koivula, Matti J

2011-01-01

Classic studies have successfully linked single-species abundances, life-history traits, assemblage structures and biomass of carabid beetles to past and present, human-caused environmental impacts and variation in 'natural' conditions. This evidence has led many to suggest carabids to function as 'indicators' - a term that bears multiple meanings. Here, a conservation-oriented definition for an indicator is used, carabid indicator potential from seven views is evaluated, and ways to proceed in indicator research are discussed. (1) Carabid species richness poorly indicates the richness and abundance of other taxa, which underlines the importance of using multiple taxa in environmental assessments. The ability of assemblage indices and specialist or functional-group abundances to reflect rare species and habitats should be examined in detail. (2) Experimental evidence suggests that carabids may potentially serve as keystone indicators. (3) Carabids are sensitive to human-altered abiotic conditions, such as pesticide use in agro-ecosystems and heavy metal contamination of soils. Carabids might thus reflect ecological sustainability and 'ecosystem health'. (4) Carabid assemblages host abundant species characteristic of particular habitat types or successional stages, which makes them promising dominance indicators. (5) Carabids reflect variation in 'natural' conditions, but vegetation and structural features are more commonly adopted as condition indicators. Carabids nevertheless provide yet another, equally accurate, view on the structure of the environment. (6) Carabids may function as early-warning signalers, as suggested by recent studies linking climate and carabid distributions. (7) Carabids reflect natural and human-caused disturbances and management, but the usefulness of these responses for conservation purposes requires further research. In summary, European carabids appear useful model organisms and possibly indicators because they are diverse

Useful model organisms, indicators, or both? Ground beetles (Coleoptera, Carabidae reflecting environmental conditions

Directory of Open Access Journals (Sweden)

Matti Koivula

2011-05-01

Full Text Available Classic studies have successfully linked single-species abundances, life-history traits, assemblage structures and biomass of carabid beetles to past and present, human-caused environmental impacts and variation in ‘natural’ conditions. This evidence has led many to suggest carabids to function as ‘indicators’ − a term that bears multiple meanings. Here, a conservation-oriented definition for an indicator is used, carabid indicator potential from seven views is evaluated, and ways to proceed in indicator research are discussed. (1 Carabid species richness poorly indicates the richness and abundance of other taxa, which underlines the importance of using multiple taxa in environmental assessments. The ability of assemblage indices and specialist or functional-group abundances to reflect rare species and habitats should be examined in detail. (2 Experimental evidence suggests that carabids may potentially serve as keystone indicators. (3 Carabids are sensitive to human-altered abiotic conditions, such as pesticide use in agro-ecosystems and heavy metal contamination of soils. Carabids might thus reflect ecological sustainability and ‘ecosystem health’. (4 Carabid assemblages host abundant species characteristic of particular habitat types or successional stages, which makes them promising dominance indicators. (5 Carabids reflect variation in ‘natural’ conditions, but vegetation and structural features are more commonly adopted as condition indicators. Carabids nevertheless provide yet another, equally accurate, view on the structure of the environment. (6 Carabids may function as early-warning signalers, as suggested by recent studies linking climate and carabid distributions. (7 Carabids reflect natural and human-caused disturbances and management, but the usefulness of these responses for conservation purposes requires further research. In summary, European carabids appear useful model organisms and possibly indicators because

New Regions of the Human Genome Linked to Skin Color Variation in Some African Populations

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In the first study of its kind, an international team of genomics researchers has identified new regions of the human genome that are associated with skin color variation in some African populations, opening new avenues for research on skin diseases and cancer in all populations.

Do we have to choose between feeding the human population and conserving nature? Modelling the global dependence of people on ecosystem services.

Science.gov (United States)

Cazalis, Victor; Loreau, Michel; Henderson, Kirsten

2018-09-01

The ability of the human population to continue growing depends strongly on the ecosystem services provided by nature. Nature, however, is becoming more and more degraded as the number of individuals increases, which could potentially threaten the future well-being of the human population. We use a dynamic model to conceptualise links between the global proportion of natural habitats and human demography, through four categories of ecosystem services (provisioning, regulating, cultural recreational and informational) to investigate the common future of nature and humanity in terms of size and well-being. Our model shows that there is generally a trade-off between the quality of life and human population size and identifies four short-term scenarios, corresponding to three long-term steady states of the model. First, human population could experience declines if nature becomes too degraded and regulating services diminish; second the majority of the population could be in a famine state, where the population continues to grow with minimal food provision. Between these scenarios, a desirable future scenario emerges from the model. It occurs if humans convert enough land to feed all the population, while maintaining biodiversity and ecosystem services. Finally, we find a fourth scenario, which combines famine and a decline in the population because of an overexploitation of land leading to a decrease in food production. Human demography is embedded in natural dynamics; the two factors should be considered together if we are to identify a desirable future for both nature and humans. Copyright © 2018 Elsevier B.V. All rights reserved.

Spatial relationship between human population density, land use intensity and biodiversity in the Czech Republic

Czech Academy of Sciences Publication Activity Database

Vačkář, David; Chobot, K.; Orlitová, E.

2012-01-01

Roč. 27, č. 9 (2012), s. 1279-1290 ISSN 0921-2973 Institutional support: RVO:67179843 Keywords : species richness * landscape diversity * human population density * human appropriation of net primary production * Czech Republic Subject RIV: EH - Ecology, Behaviour Impact factor: 2.897, year: 2012

Determination of combined sibship indices "gray zone" using 15 STR loci for central Bosnian human population.

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Musanovic, Jasmin; Filipovska-Musanovic, Marijana; Kovacevic, Lejla; Buljugic, Dzenisa; Dzehverovic, Mirela; Avdic, Jasna; Marjanovic, Damir

2012-05-01

In our previous population studies of Bosnia and Herzegovina human population, we have used autosomal STR, Y-STR, and X-STR loci, as well as Y-chromosome NRY biallelic markers. All obtained results were included in Bosnian referent database. In order of future development of applied population molecular genetics researches of Bosnia and Herzegovina human population, we have examined the effectiveness of 15 STR loci system in determination of sibship by using 15 STR loci and calculating different cut-off points of combined sibship indices (CSI) and distribution of sharing alleles. From the perspective of its application, it is very difficult and complicated to establish strict CSI cut-off values for determination of the doubtless sibship. High statistically significant difference between the means of CSI values and in distribution of alleles sharing in siblings and non-siblings was noticed (P < 0.0001). After constructing the "gray zone", only one false positive result was found in three CSI cut-off levels with the highest percent of determined sibship/non-sibship at the CSI = 0.067, confirming its practical benefit. Concerning the distribution of sharing alleles, it is recommended as an informative estimator for its usage within Bosnia and Herzegovina human population.

Resource mapping and emergency preparedness to infectious diseases in human and animal populations in Kibaha and Ngorongoro districts, Tanzania

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E.D. Karimuribo

2012-06-01

Full Text Available A rapid situation analysis was conducted in Kibaha and Ngorongoro districts in Tanzania to map resources as well as analysing emergency preparedness to infectious diseases in animal (domestic and wild and human populations. Kibaha was chosen as a district close to a commercial city (Dar es Salaam while Ngorongoro represented a remote, border district with high interactions between humans, domestic and wild animals. In this study, data on resources and personnel as well as emergency preparedness were collected from all wards (n = 22, human health facilities (n = 40 and livestock facilities in the two districts using interview checklists and questionnaires. Descriptive statistics for resources were calculated and mapped by district. Kibaha district had a higher human population density, more health workers, better equipped health facilities and better communication and transport systems. On the other hand, Ngorongoro had a higher population of livestock and more animal health facilities but a poorer ratio of animal health workers to livestock. The average ratio of health personnel to population in catchment areas of the health facilities was 1:147 (range of 1:17−1:1200. The ratio of personnel to human population was significantly higher in Kibaha (1:95 than in Ngorongoro (1:203 district (p = 0 < 0.001. Considering the limited resources available to both human and animal health sectors and their different strengths and weaknesses there are opportunities for greater collaboration and resource-sharing between human and animal health for improved surveillance and emergency-preparedness.

HIV epidemiology. The early spread and epidemic ignition of HIV-1 in human populations.

Science.gov (United States)

Faria, Nuno R; Rambaut, Andrew; Suchard, Marc A; Baele, Guy; Bedford, Trevor; Ward, Melissa J; Tatem, Andrew J; Sousa, João D; Arinaminpathy, Nimalan; Pépin, Jacques; Posada, David; Peeters, Martine; Pybus, Oliver G; Lemey, Philippe

2014-10-03

Thirty years after the discovery of HIV-1, the early transmission, dissemination, and establishment of the virus in human populations remain unclear. Using statistical approaches applied to HIV-1 sequence data from central Africa, we show that from the 1920s Kinshasa (in what is now the Democratic Republic of Congo) was the focus of early transmission and the source of pre-1960 pandemic viruses elsewhere. Location and dating estimates were validated using the earliest HIV-1 archival sample, also from Kinshasa. The epidemic histories of HIV-1 group M and nonpandemic group O were similar until ~1960, after which group M underwent an epidemiological transition and outpaced regional population growth. Our results reconstruct the early dynamics of HIV-1 and emphasize the role of social changes and transport networks in the establishment of this virus in human populations. Copyright © 2014, American Association for the Advancement of Science.

[Health and humanization Diploma: the value of reflection and face to face learning].

Science.gov (United States)

Martínez-Gutiérrez, Javiera; Magliozzi, Pietro; Torres, Patricio; Soto, Mauricio; Walker, Rosa

2015-03-01

In a rapidly changing culture like ours, with emphasis on productivity, there is a strong need to find the meaning of health care work using learning instances that privilege reflection and face to face contact with others. The Diploma in Health and Humanization (DSH), was developed as an interdisciplinary space for training on issues related to humanization. To analyze the experience of DSH aiming to identify the elements that students considered key factors for the success of the program. We conducted a focus group with DSH graduates, identifying factors associated with satisfaction. Transcripts were coded and analyzed by two independent reviewers. DSH graduates valued a safe space, personal interaction, dialogue and respect as learning tools of the DSH. They also appreciates the opportunity to have emotional interactions among students and between them and the teacher as well as the opportunity to share personal stories and their own search for meaning. DSH is a learning experience in which their graduates value the ability to think about their vocation and the affective interaction with peers and teachers. We hope to contribute to the development of face to face courses in the area of humanization. Face to face methodology is an excellent teaching technique for contents related to the meaning of work, and more specifically, to a group of learners that require affective communication and a personal connection of their work with their own values and beliefs.

Directional and balancing selection in human beta-defensins

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Armour John AL

2008-04-01

Full Text Available Abstract Background In primates, infection is an important force driving gene evolution, and this is reflected in the importance of infectious disease in human morbidity today. The beta-defensins are key components of the innate immune system, with antimicrobial and cell signalling roles, but also reproductive functions. Here we examine evolution of beta-defensins in catarrhine primates and variation within different human populations. Results We show that five beta-defensin genes that do not show copy number variation in humans show evidence of positive selection in catarrhine primates, and identify specific codons that have been under selective pressure. Direct haplotyping of DEFB127 in humans suggests long-term balancing selection: there are two highly diverged haplotype clades carrying different variants of a codon that, in primates, is positively selected. For DEFB132, we show that extensive diversity, including a four-state amino acid polymorphism (valine, isoleucine, alanine and threonine at position 93, is present in hunter-gatherer populations, both African and non-African, but not found in samples from agricultural populations. Conclusion Some, but not all, beta-defensin genes show positive selection in catarrhine primates. There is suggestive evidence of different selective pressures on these genes in humans, but the nature of the selective pressure remains unclear and is likely to differ between populations.

[Self-reflection, interpersonal behavior and psychoanalytic ethics].

Science.gov (United States)

Bürgy, M

1997-05-01

In the middle ages, ethical practice included a metaphysical theory of value. In comparison with that, self-reflection and interpersonality should be described as principles of more individual ethics and proceeding from philosophy to psychoanalysis in modern times. Drawing a borderline between human philosophy and metaphysies, Kant defined his so-called categorial imperative as a basic phenomenon of human reciprocity. Ethical relationship to another person, however, requires realization of one's own self, i.e. self-reflection. Hegel's subsequent association of intersubjectivity and selfreflection supplied the basis for Sarte's constitution of consciousness: Existence as existing for the good of the fellow-being. Self-reflection, basing on the sight of one's own self by the other person, leads to Sartre's concept of existential psychoanalysis and to his understanding of ethics. His concept illustrates the decline of significance of philosophy for the analysis of human relationship. Habermas describes self-reflection and interpersonality as fundamental principles of the psychoanalytic therapy and its ethical demands. With the historical concept of the super-ego, Freud established therapeutical one-sidedness and abstinence from ethics; however, as therapeutical interrelationship continued to intensity, ethics of depth psychology also began to develop. This ethical demand was not expressly formulated within the context of psychoanalysis, with the exception of jung and his epigones. Nevertheless, psychoanalytic interaction implies the development of self-reflection, which definitely represents a step forward in the sense of "ethical enlightenment" represented by Kant.

Signal-enhancement reflective pulse oximeter with Fresnel lens

Science.gov (United States)

Chung, Shuang-Chao; Sun, Ching-Cherng

2016-09-01

In this paper, a new reflective pulse oximeter is proposed and demonstrated with implanting a Fresnel lens, which enhances the reflected signal. An optical simulation model incorporated with human skin characteristics is presented to evaluate the capability of the Fresnel lens. In addition, the distance between the light emitting diode and the photodiode is optimized. Compared with the other reflective oximeters, the reflected signal light detected by the photodiode is enhanced to more than 140%.

Surveillance for yellow Fever virus in non-human primates in southern Brazil, 2001-2011: a tool for prioritizing human populations for vaccination.

OpenAIRE

Marco A B Almeida; Jader da C Cardoso; Edmilson Dos Santos; Daltro F da Fonseca; Laura L Cruz; Fernando J C Faraco; Marilina A Bercini; Kátia C Vettorello; Mariana A Porto; Renate Mohrdieck; Tani M S Ranieri; Maria T Schermann; Alethéa F Sperb; Francisco Z Paz; Zenaida M A Nunes

2014-01-01

Author Summary Yellow fever (YF) is a viral hemorrhagic disease that affects humans as well as several species of non-human primates, especially New World monkeys found in South America. Yellow fever virus (YFV) is maintained in a natural cycle involving tree-hole breeding mosquitoes and non-human primates hosts. Because YF is often fatal in susceptible New World monkey populations, sudden die-offs of New World monkeys or epizootics can signal YFV circulation in an environment where humans ma...

Different but overlapping populations of Strongyloides stercoralis in dogs and humans-Dogs as a possible source for zoonotic strongyloidiasis.

Science.gov (United States)

Jaleta, Tegegn G; Zhou, Siyu; Bemm, Felix M; Schär, Fabian; Khieu, Virak; Muth, Sinuon; Odermatt, Peter; Lok, James B; Streit, Adrian

2017-08-01

Strongyloidiasis is a much-neglected soil born helminthiasis caused by the nematode Strongyloides stercoralis. Human derived S. stercoralis can be maintained in dogs in the laboratory and this parasite has been reported to also occur in dogs in the wild. Some authors have considered strongyloidiasis a zoonotic disease while others have argued that the two hosts carry host specialized populations of S. stercoralis and that dogs play a minor role, if any, as a reservoir for zoonotic S. stercoralis infections of humans. We isolated S. stercoralis from humans and their dogs in rural villages in northern Cambodia, a region with a high incidence of strongyloidiasis, and compared the worms derived from these two host species using nuclear and mitochondrial DNA sequence polymorphisms. We found that in dogs there exist two populations of S. stercoralis, which are clearly separated from each other genetically based on the nuclear 18S rDNA, the mitochondrial cox1 locus and whole genome sequence. One population, to which the majority of the worms belong, appears to be restricted to dogs. The other population is indistinguishable from the population of S. stercoralis isolated from humans. Consistent with earlier studies, we found multiple sequence variants of the hypervariable region I of the 18 S rDNA in S. stercoralis from humans. However, comparison of mitochondrial sequences and whole genome analysis suggest that these different 18S variants do not represent multiple genetically isolated subpopulations among the worms isolated from humans. We also investigated the mode of reproduction of the free-living generations of laboratory and wild isolates of S. stercoralis. Contrary to earlier literature on S. stercoralis but similar to other species of Strongyloides, we found clear evidence of sexual reproduction. Overall, our results show that dogs carry two populations, possibly different species of Strongyloides. One population appears to be dog specific but the other one is

Reflective Drawing as a Tool for Reflection in Design Research

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Calvo, Mirian

2017-01-01

This article explores the role of drawing as a tool for reflection. It reports on a PhD research project that aims to identify and analyse the value that co-design processes can bring to participants and their communities. The research is associated with Leapfrog, a three-year project funded by the UK Arts and Humanities Research Council (AHRC).…

Age-related patterns in human myeloid dendritic cell populations in people exposed to Schistosoma haematobium infection.

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Norman Nausch

Full Text Available Urogenital schistosomiasis is caused by the helminth parasite Schistosoma haematobium. In high transmission areas, children acquire schistosome infection early in life with infection levels peaking in early childhood and subsequently declining in late childhood. This age-related infection profile is thought to result from the gradual development of protective acquired immunity. Age-related differences in schistosome-specific humoral and cellular responses have been reported from several field studies. However there has not yet been a systematic study of the age-related changes in human dendritic cells, the drivers of T cell polarisation.Peripheral blood mononuclear cells were obtained from a cohort of 61 Zimbabwean aged 5-45 years with a S. haematobium prevalence of 47.5%. Two subsets of dendritic cells, myeloid and plasmacytoid dendritic cells (mDCs and pDCs, were analyzed by flow cytometry.In this population, schistosome infection levels peaked in the youngest age group (5-9 years, and declined in late childhood and adulthood (10+ years. The proportions of both mDCs and pDCs varied with age. However, for mDCs the age profile depended on host infection status. In the youngest age group infected people had enhanced proportions of mDCs as well as lower levels of HLA-DR on mDCs than un-infected people. In the older age groups (10-13 and 14-45 years infected people had lower proportions of mDCs compared to un-infected individuals, but no infection status-related differences were observed in their levels of HLA-DR. Moreover mDC proportions correlated with levels of schistosome-specific IgG, which can be associated with protective immunity. In contrast proportions of pDCs varied with host age, but not with infection status.Our results show that dendritic cell proportions and activation in a human population living in schistosome-endemic areas vary with host age reflecting differences in cumulative history of exposure to schistosome infection.

Reflecting on life, not on the mind – The concept of self-reflection without stability

DEFF Research Database (Denmark)

Jensen, Lasse Meinert

This paper presents a critique of the concept of “reflection” and a theoretical alternative. I’ll argue that current notions of reflections to a large extend deals only with “meta-reflection” or “self-reflection”, and that the main problem with such conceptualizations is their preoccupation...... with “stability”. When self-reflection is conceptualized as a second-order process charged with creating diachronic continuity in the person’s life, as it often is in both philosophy (Frankfurt, 1971), cognitive theory (Carver, Scheier & Fulton, 2008), and narrative theories of personality (McAdams, 2008......), “Stability” and how it is brought about, becomes the main concern. But presupposing “stability” as the main aim of self-reflection isolates reflection to a mental realm. Human beings are certainly self-conscious, but – following Dreier (1999), when he points out that reflection is not a distancing from...

Haplotype frequencies at the DRD2 locus in populations of the East European Plain

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Mikulich Alexey I

2009-09-01

Full Text Available Abstract Background It was demonstrated previously that the three-locus RFLP haplotype, TaqI B-TaqI D-TaqI A (B-D-A, at the DRD2 locus constitutes a powerful genetic marker and probably reflects the most ancient dispersal of anatomically modern humans. Results We investigated TaqI B, BclI, MboI, TaqI D, and TaqI A RFLPs in 17 contemporary populations of the East European Plain and Siberia. Most of these populations belong to the Indo-European or Uralic language families. We identified three common haplotypes, which occurred in more than 90% of chromosomes investigated. The frequencies of the haplotypes differed according to linguistic and geographical affiliation. Conclusion Populations in the northwestern (Byelorussians from Mjadel', northern (Russians from Mezen' and Oshevensk, and eastern (Russians from Puchezh parts of the East European Plain had relatively high frequencies of haplotype B2-D2-A2, which may reflect admixture with Uralic-speaking populations that inhabited all of these regions in the Early Middle Ages.

Variations in Urine Calcium Isotope: Composition Reflect Changes in Bone Mineral Balance in Humans

Science.gov (United States)

Skulan, Joseph; Anbar, Ariel; Bullen, Thomas; Puzas, J. Edward; Shackelford, Linda; Smith, Scott M.

2004-01-01

Changes in bone mineral balance cause rapid and systematic changes in the calcium isotope composition of human urine. Urine from subjects in a 17 week bed rest study was analyzed for calcium isotopic composition. Comparison of isotopic data with measurements of bone mineral density and metabolic markers of bone metabolism indicates the calcium isotope composition of urine reflects changes in bone mineral balance. Urine calcium isotope composition probably is affected by both bone metabolism and renal processes. Calcium isotope. analysis of urine and other tissues may provide information on bone mineral balance that is in important respects better than that available from other techniques, and illustrates the usefulness of applying geochemical techniques to biomedical problems.

Key populations and human rights in the context of HIV services rendition in Ghana.

Science.gov (United States)

Laar, Amos; DeBruin, Debra

2017-08-02

In line with its half century old penal code, Ghana currently criminalizes and penalizes behaviors of some key populations - populations deemed to be at higher risk of acquiring or transmitting Human Immunodeficiency Virus (HIV). Men who have sex with men (MSM), and sex workers (SWs) fit into this categorization. This paper provides an analysis of how enactment and implementation of rights-limiting laws not only limit rights, but also amplify risk and vulnerability to HIV in key and general populations. The paper derives from a project that assessed the ethics sensitivity of key documents guiding Ghana's response to its HIV epidemic. Assessment was guided by leading frameworks from public health ethics, and relevant articles from the international bill of rights. Ghana's response to her HIV epidemic does not adequately address the rights and needs of key populations. Even though the national response has achieved some public health successes, palpable efforts to address rights issues remain nascent. Ghana's guiding documents for HIV response include no advocacy for decriminalization, depenalization or harm reduction approaches for these key populations. The impact of rights-restricting codes on the nation's HIV epidemic is real: criminalization impedes key populations' access to HIV prevention and treatment services. Given that they are bridging populations, whatever affects the Ghanaian key populations directly, affects the general population indirectly. The right to the highest attainable standard of health, without qualification, is generally acknowledged as a fundamental human right. Unfortunately, this right currently eludes the Ghanaian SW and MSM. The paper endorses decriminalization as a means of promoting this right. In the face of opposition to decriminalization, the paper proposes specific harm reduction strategies as approaches to promote health and uplift the diminished rights of key populations. Thus the authors call on Ghana to remove impediments to

Epidemiology and seroepidemiology of human enterovirus 71 among Thai populations

Science.gov (United States)

2014-01-01

Background Human enterovirus 71 (EV71) is an important pathogen caused large outbreaks in Asian-Pacific region with severe neurological complications and may lead to death in young children. Understanding of the etiological spectrum and epidemic changes of enterovirus and population’s immunity against EV71 are crucial for the implementation of future therapeutic and prophylactic intervention. Results A total of 1,182 patients who presented with the symptoms of hand foot and mouth disease (67.3%) or herpangina (HA) (16.7%) and admitted to the hospitals during 2008-2013 were tested for enterovirus using pan-enterovirus PCR targeting 5′-untranslated region and specific PCR for viral capsid protein 1 gene. Overall, 59.7% were pan-enterovirus positive comprising 9.1% EV71 and 31.2% coxsackievirus species A (CV-A) including 70.5% CV-A6, 27.6% CV-A16, 1.1% CV-A10, and 0.8% CV-A5. HFMD and HA occurred endemically during 2008-2011. The number of cases increased dramatically in June 2012 with the percentage of the recently emerged CV-A6 significantly rose to 28.4%. Co-circulation between different EV71 genotypes was observed during the outbreak. Total of 161 sera obtained from healthy individuals were tested for neutralizing antibodies (NAb) against EV71 subgenotype B5 (EV71-B5) using microneutralization assay. The seropositive rate of EV71-B5 was 65.8%. The age-adjusted seroprevalence for individuals was found to be lowest in children aged >6 months to 2 years (42.5%). The seropositive rate remained relatively low in preschool children aged > 2 years to 6 years (48.3%) and thereafter increased sharply to more than 80% in individuals aged > 6 years. Conclusions This study describes longitudinal data reflecting changing patterns of enterovirus prevalence over 6 years and demonstrates high seroprevalences of EV71-B5 NAb among Thai individuals. The rate of EV71 seropositive increased with age but without gender-specific significant difference. We identified

The history of human populations in the Japanese Archipelago inferred from genome-wide SNP data with a special reference to the Ainu and the Ryukyuan populations.

Science.gov (United States)

Jinam, Timothy; Nishida, Nao; Hirai, Momoki; Kawamura, Shoji; Oota, Hiroki; Umetsu, Kazuo; Kimura, Ryosuke; Ohashi, Jun; Tajima, Atsushi; Yamamoto, Toshimichi; Tanabe, Hideyuki; Mano, Shuhei; Suto, Yumiko; Kaname, Tadashi; Naritomi, Kenji; Yanagi, Kumiko; Niikawa, Norio; Omoto, Keiichi; Tokunaga, Katsushi; Saitou, Naruya

2012-12-01

The Japanese Archipelago stretches over 4000 km from north to south, and is the homeland of the three human populations; the Ainu, the Mainland Japanese and the Ryukyuan. The archeological evidence of human residence on this Archipelago goes back to >30 000 years, and various migration routes and root populations have been proposed. Here, we determined close to one million single-nucleotide polymorphisms (SNPs) for the Ainu and the Ryukyuan, and compared these with existing data sets. This is the first report of these genome-wide SNP data. Major findings are: (1) Recent admixture with the Mainland Japanese was observed for more than one third of the Ainu individuals from principal component analysis and frappe analyses; (2) The Ainu population seems to have experienced admixture with another population, and a combination of two types of admixtures is the unique characteristics of this population; (3) The Ainu and the Ryukyuan are tightly clustered with 100% bootstrap probability followed by the Mainland Japanese in the phylogenetic trees of East Eurasian populations. These results clearly support the dual structure model on the Japanese Archipelago populations, though the origins of the Jomon and the Yayoi people still remain to be solved.

Modeling Sustainability: Population, Inequality, Consumption, and Bidirectional Coupling of the Earth and Human Systems

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Motesharrei, Safa; Rivas, Jorge; Kalnay, Eugenia; Asrar, Ghassem R.; Busalacchi, Antonio J.; Cahalan, Robert F.; Cane, Mark A.; Colwell, Rita R.; Feng, Kuishuang; Franklin, Rachel S.;

Modeling Sustainability: Population, Inequality, Consumption, and Bidirectional Coupling of the Earth and Human Systems

Energy Technology Data Exchange (ETDEWEB)

Motesharrei, Safa; Rivas, Jorge; Kalnay, Eugenia; Asrar, Ghassem R.; Busalacchi, Antonio J.; Cahalan, Robert F.; Cane, Mark A.; Colwell, Rita R.; Feng, Kuishuang; Franklin, Rachel S.; Hubacek, Klaus; Miralles-Wilhelm, Fernando; Miyoshi, Takemasa; Ruth, Matthias; Sagdeev, Roald; Shirmohammadi, Adel; Shukla, Jagadish; Srebric, Jelena; Yakovenko, Victor M.; Zeng, Ning

2016-12-11

Over the last two centuries, the impact of the Human System has grown dramatically, becoming strongly dominant within the Earth System in many different ways. Consumption, inequality, and population have increased extremely fast, especially since about 1950, threatening to overwhelm the many critical functions and ecosystems of the Earth System. Changes in the Earth System, in turn, have important feedback effects on the Human System, with costly and potentially serious consequences. However, current models do not incorporate these critical feedbacks. We argue that in order to understand the dynamics of either system, Earth System Models must be coupled with Human System Models through bidirectional couplings representing the positive, negative, and delayed feedbacks that exist in the real systems. In particular, key Human System variables, such as demographics, inequality, economic growth, and migration, are not coupled with the Earth System but are instead driven by exogenous estimates, such as United Nations population projections. This makes current models likely to miss important feedbacks in the real Earth–Human system, especially those that may result in unexpected or counterintuitive outcomes, and thus requiring different policy interventions from current models. The importance and imminence of sustainability challenges, the dominant role of the Human System in the Earth System, and the essential roles the Earth System plays for the Human System, all call for collaboration of natural scientists, social scientists, and engineers in multidisciplinary research and modeling to develop coupled Earth–Human system models for devising effective science-based policies and measures to benefit current and future generations.

Genetic radiation effects and natural radioactivity of human population in Brazil

International Nuclear Information System (INIS)

Freire-Maia, A.

1972-01-01

A study on areas of natural radioactivity is done, covering the genetic effects on human population. The study is done in depth dealing with aspecto such as radioactive area involved, discussion of materials and methods, errors and fallacies, influential factors, models, buildup and natural radioactivity, hypotheses, results and perspectives, etc. It covers 24 localites, 8.572 couples and 43.930 pregnancy cases [pt

Pollution gets personal! A first population-based human biomonitoring study in Austria.

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Hohenblum, Philipp; Steinbichl, Philipp; Raffesberg, Wolfgang; Weiss, Stefan; Moche, Wolfgang; Vallant, Birgit; Scharf, Sigrid; Haluza, Daniela; Moshammer, Hanns; Kundi, Michael; Piegler, Brigitte; Wallner, Peter; Hutter, Hans-Peter

2012-02-01

Humans are exposed to a broad variety of man-made chemicals. Human biomonitoring (HBM) data reveal the individual body burden irrespective of sources and routes of uptake. A first population-based study was started in Austria in 2008 and was finished at the end of May 2011. This cross sectional study aims at documenting the extent, the distribution and the determinants of human exposure to industrial chemicals as well as proving the feasibility of a representative HBM study. Overall, 150 volunteers (50 families) were selected by stratified random sampling. Exposure to phthalates, trisphosphates, polybrominated diphenyl ethers (PBDE), bisphenol A (along with nonyl- and octyl phenol) and methyl mercury was assessed. Sixteen of 18 PBDE determined were detected above the limit of quantification (LOQ) in blood samples with #153 and #197 the most abundant species. Bisphenol A in urine was measured in a subsample of 25 with only 4 samples found above the LOQ. In 3 of 100 urine samples at least one of 8 trisphosphate compounds assessed was above the LOQ. These first analytical results of the human biomonitoring data show that the body burden of the Austrian population with respect to the assessed compounds is comparable to or even lower than in other European countries. Overall, the study revealed that in order to develop a feasible protocol for representative human biomonitoring studies procedures have to be optimized to allow for non-invasive sampling of body tissues in accordance with the main metabolic pathways. Procedures of participants' recruitment were, however, labor intensive and have to be improved. Copyright © 2011 Elsevier GmbH. All rights reserved.

Population Genetic Structure of the People of Qatar

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Hunter-Zinck, Haley; Musharoff, Shaila; Salit, Jacqueline; Al-Ali, Khalid A.; Chouchane, Lotfi; Gohar, Abeer; Matthews, Rebecca; Butler, Marcus W.; Fuller, Jennifer; Hackett, Neil R.; Crystal, Ronald G.; Clark, Andrew G.

2010-01-01

People of the Qatar peninsula represent a relatively recent founding by a small number of families from three tribes of the Arabian Peninsula, Persia, and Oman, with indications of African admixture. To assess the roles of both this founding effect and the customary first-cousin marriages among the ancestral Islamic populations in Qatar's population genetic structure, we obtained and genotyped with Affymetrix 500k SNP arrays DNA samples from 168 self-reported Qatari nationals sampled from Doha, Qatar. Principal components analysis was performed along with samples from the Human Genetic Diversity Project data set, revealing three clear clusters of genotypes whose proximity to other human population samples is consistent with Arabian origin, a more eastern or Persian origin, and individuals with African admixture. The extent of linkage disequilibrium (LD) is greater than that of African populations, and runs of homozygosity in some individuals reflect substantial consanguinity. However, the variance in runs of homozygosity is exceptionally high, and the degree of identity-by-descent sharing generally appears to be lower than expected for a population in which nearly half of marriages are between first cousins. Despite the fact that the SNPs of the Affymetrix 500k chip were ascertained with a bias toward SNPs common in Europeans, the data strongly support the notion that the Qatari population could provide a valuable resource for the mapping of genes associated with complex disorders and that tests of pairwise interactions are particularly empowered by populations with elevated LD like the Qatari. PMID:20579625

The genome of a Mongolian individual reveals the genetic imprints of Mongolians on modern human populations.

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Bai, Haihua; Guo, Xiaosen; Zhang, Dong; Narisu, Narisu; Bu, Junjie; Jirimutu, Jirimutu; Liang, Fan; Zhao, Xiang; Xing, Yanping; Wang, Dingzhu; Li, Tongda; Zhang, Yanru; Guan, Baozhu; Yang, Xukui; Yang, Zili; Shuangshan, Shuangshan; Su, Zhe; Wu, Huiguang; Li, Wenjing; Chen, Ming; Zhu, Shilin; Bayinnamula, Bayinnamula; Chang, Yuqi; Gao, Ying; Lan, Tianming; Suyalatu, Suyalatu; Huang, Hui; Su, Yan; Chen, Yujie; Li, Wenqi; Yang, Xu; Feng, Qiang; Wang, Jian; Yang, Huanming; Wang, Jun; Wu, Qizhu; Yin, Ye; Zhou, Huanmin

2014-11-05

Mongolians have played a significant role in modern human evolution, especially after the rise of Genghis Khan (1162[?]-1227). Although the social cultural impacts of Genghis Khan and the Mongolian population have been well documented, explorations of their genome structure and genetic imprints on other human populations have been lacking. We here present the genome of a Mongolian male individual. The genome was de novo assembled using a total of 130.8-fold genomic data produced from massively parallel whole-genome sequencing. We identified high-confidence variation sets, including 3.7 million single nucleotide polymorphisms (SNPs) and 756,234 short insertions and deletions. Functional SNP analysis predicted that the individual has a pathogenic risk for carnitine deficiency. We located the patrilineal inheritance of the Mongolian genome to the lineage D3a through Y haplogroup analysis and inferred that the individual has a common patrilineal ancestor with Tibeto-Burman populations and is likely to be the progeny of the earliest settlers in East Asia. We finally investigated the genetic imprints of Mongolians on other human populations using different approaches. We found varying degrees of gene flows between Mongolians and populations living in Europe, South/Central Asia, and the Indian subcontinent. The analyses demonstrate that the genetic impacts of Mongolians likely resulted from the expansion of the Mongolian Empire in the 13th century. The genome will be of great help in further explorations of modern human evolution and genetic causes of diseases/traits specific to Mongolians. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Are great apes able to reason from multi-item samples to populations of food items?

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Eckert, Johanna; Rakoczy, Hannes; Call, Josep

2017-10-01

Inductive learning from limited observations is a cognitive capacity of fundamental importance. In humans, it is underwritten by our intuitive statistics, the ability to draw systematic inferences from populations to randomly drawn samples and vice versa. According to recent research in cognitive development, human intuitive statistics develops early in infancy. Recent work in comparative psychology has produced first evidence for analogous cognitive capacities in great apes who flexibly drew inferences from populations to samples. In the present study, we investigated whether great apes (Pongo abelii, Pan troglodytes, Pan paniscus, Gorilla gorilla) also draw inductive inferences in the opposite direction, from samples to populations. In two experiments, apes saw an experimenter randomly drawing one multi-item sample from each of two populations of food items. The populations differed in their proportion of preferred to neutral items (24:6 vs. 6:24) but apes saw only the distribution of food items in the samples that reflected the distribution of the respective populations (e.g., 4:1 vs. 1:4). Based on this observation they were then allowed to choose between the two populations. Results show that apes seemed to make inferences from samples to populations and thus chose the population from which the more favorable (4:1) sample was drawn in Experiment 1. In this experiment, the more attractive sample not only contained proportionally but also absolutely more preferred food items than the less attractive sample. Experiment 2, however, revealed that when absolute and relative frequencies were disentangled, apes performed at chance level. Whether these limitations in apes' performance reflect true limits of cognitive competence or merely performance limitations due to accessory task demands is still an open question. © 2017 Wiley Periodicals, Inc.

Human disturbance influences reproductive success and growth rate in California sea lions (Zalophus californianus.

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Susannah S French

Full Text Available The environment is currently undergoing changes at both global (e.g., climate change and local (e.g., tourism, pollution, habitat modification scales that have the capacity to affect the viability of animal and plant populations. Many of these changes, such as human disturbance, have an anthropogenic origin and therefore may be mitigated by management action. To do so requires an understanding of the impact of human activities and changing environmental conditions on population dynamics. We investigated the influence of human activity on important life history parameters (reproductive rate, and body condition, and growth rate of neonate pups for California sea lions (Zalophus californianus in the Gulf of California, Mexico. Increased human presence was associated with lower reproductive rates, which translated into reduced long-term population growth rates and suggested that human activities are a disturbance that could lead to population declines. We also observed higher body growth rates in pups with increased exposure to humans. Increased growth rates in pups may reflect a density dependent response to declining reproductive rates (e.g., decreased competition for resources. Our results highlight the potentially complex changes in life history parameters that may result from human disturbance, and their implication for population dynamics. We recommend careful monitoring of human activities in the Gulf of California and emphasize the importance of management strategies that explicitly consider the potential impact of human activities such as ecotourism on vertebrate populations.

Global climate change, war, and population decline in recent human history.

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Zhang, David D; Brecke, Peter; Lee, Harry F; He, Yuan-Qing; Zhang, Jane

2007-12-04

Although scientists have warned of possible social perils resulting from climate change, the impacts of long-term climate change on social unrest and population collapse have not been quantitatively investigated. In this study, high-resolution paleo-climatic data have been used to explore at a macroscale the effects of climate change on the outbreak of war and population decline in the preindustrial era. We show that long-term fluctuations of war frequency and population changes followed the cycles of temperature change. Further analyses show that cooling impeded agricultural production, which brought about a series of serious social problems, including price inflation, then successively war outbreak, famine, and population decline successively. The findings suggest that worldwide and synchronistic war-peace, population, and price cycles in recent centuries have been driven mainly by long-term climate change. The findings also imply that social mechanisms that might mitigate the impact of climate change were not significantly effective during the study period. Climate change may thus have played a more important role and imposed a wider ranging effect on human civilization than has so far been suggested. Findings of this research may lend an additional dimension to the classic concepts of Malthusianism and Darwinism.

The Cultivation of Humanities and Emotions. Reflections on Moral and Political Education

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Marta Gil

2017-05-01

Full Text Available The present paper involves a reflection on the current orientation that education is adopting based on Martha Nussbaum’s thinking. Under the imperative of the economic growth, education is seen as a mere means to achieve success in the job market, and arts and humanities are being marginalized from study programs increasingly. We will talk about the cultivation of empathic imagination and compassion as mechanisms that help us to understand people that are different from us, and to acquire a concern for them. We will see why the role of these emotions might be relevant in order to prompt us to help whoever that finds himself in a vulnerability situation or suffering. This is why we will argue that the cultivation of these emotions may help us to develop a better moral agency, and also to enhance our condition as citizens, making us more sensitive towards other’s necessities, and orienting our political decisions towards cooperation and solidarity.

HOX and TALE signatures specify human stromal stem cell populations from different sources.

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Picchi, Jacopo; Trombi, Luisa; Spugnesi, Laura; Barachini, Serena; Maroni, Giorgia; Brodano, Giovanni Barbanti; Boriani, Stefano; Valtieri, Mauro; Petrini, Mario; Magli, Maria Cristina

2013-04-01

Human stromal stem cell populations reside in different tissues and anatomical sites, however a critical question related to their efficient use in regenerative medicine is whether they exhibit equivalent biological properties. Here, we compared cellular and molecular characteristics of stromal stem cells derived from the bone marrow, at different body sites (iliac crest, sternum, and vertebrae) and other tissues (dental pulp and colon). In particular, we investigated whether homeobox genes of the HOX and TALE subfamilies might provide suitable markers to identify distinct stromal cell populations, as HOX proteins control cell positional identity and, together with their co-factors TALE, are involved in orchestrating differentiation of adult tissues. Our results show that stromal populations from different sources, although immunophenotypically similar, display distinct HOX and TALE signatures, as well as different growth and differentiation abilities. Stromal stem cells from different tissues are characterized by specific HOX profiles, differing in the number and type of active genes, as well as in their level of expression. Conversely, bone marrow-derived cell populations can be essentially distinguished for the expression levels of specific HOX members, strongly suggesting that quantitative differences in HOX activity may be crucial. Taken together, our data indicate that the HOX and TALE profiles provide positional, embryological and hierarchical identity of human stromal stem cells. Furthermore, our data suggest that cell populations derived from different body sites may not represent equivalent cell sources for cell-based therapeutical strategies for regeneration and repair of specific tissues. Copyright © 2012 Wiley Periodicals, Inc.

[The awareness and attitude of population of Kazakhstan to inoculation against human papilloma virus].

Science.gov (United States)

Nasritdinova, N Yu; Reznik, V L; Kuatbaieva, A M; Kairbaiev, M R

2016-01-01

The vaccines against human papilloma virus are a potential tool for prevention of cervix cancer and particular other types of cancer. The high inclusion of target group in applied vaccination program is economically effective and successful activity depending in many instances on reliable knowledge and positive attitude of population to inoculation. The cross-sectional study was carried out using previously developed anonymous questionnaires for various groups of population in four pilot regions of Kazakhstan where national ministry of health proposes for inoculation of girls aged 9-13 years two vaccines against human papilloma virus (four- and two-valence) The data base was organized using software Microsoft Access. The materials were integrated and processed using variation statistics techniques in software IBM SPSS Statistics 19 and applying Student criterion and calculating correlation dependences. Out of all respondents, 66% were aware about existence of human papilloma virus/ the main portion of parents 'female adolescents learned about vaccination against human papilloma virus from Internet and medical workers. The most significant factor preventing implementation of vaccination and the proper perception by respondents was absence of confidence in safety of vaccine. About 54% of parents of female adolescents and 75% of teachers consider vaccine as unsafe. And only 72% of medical workers consider vaccine as safe. Despite known effectiveness of vaccination against human papilloma virus, number of problems exist related to implementation of program. The level of awareness and understanding of different groups of population concerning the role of vaccination in development of oncologic pathology and possibility of prevention of cancer at the expense of vaccination. The intersectoral relationships are to be developed between medicine and education system. The significance of information activities of medical control organs and organizations is to be enhanced.

Probabilistic estimation of residential air exchange rates for population-based human exposure modeling

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Residential air exchange rates (AERs) are a key determinant in the infiltration of ambient air pollution indoors. Population-based human exposure models using probabilistic approaches to estimate personal exposure to air pollutants have relied on input distributions from AER meas...

Testing human sperm chemotaxis: how to detect biased motion in population assays.

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Leah Armon

Full Text Available Biased motion of motile cells in a concentration gradient of a chemoattractant is frequently studied on the population level. This approach has been particularly employed in human sperm chemotactic assays, where the fraction of responsive cells is low and detection of biased motion depends on subtle differences. In these assays, statistical measures such as population odds ratios of swimming directions can be employed to infer chemotactic performance. Here, we report on an improved method to assess statistical significance of experimentally determined odds ratios and discuss the strong impact of data correlations that arise from the directional persistence of sperm swimming.

Fostering Humanism in Medicine through Art and Reflection

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Gooding, Holly C.; Quinn, Mariah; Martin, Barbara; Charrow, Alexandra; Katz, Joel T.

2016-01-01

Physician burnout and empathy erosion are common during training and clinical practice. Museums can effectively partner with health professional schools and hospitals to address these challenges through reflective practice and a focus on physician wellness. We describe a partnership between the Brigham and Women's Hospital Department of Medicine…

The Genetic Structure of Wild Orobanche cumana Wallr. (Orobanchaceae Populations in Eastern Bulgaria Reflects Introgressions from Weedy Populations

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Rocío Pineda-Martos

2014-01-01

Full Text Available Orobanche cumana is a holoparasitic plant naturally distributed from central Asia to south-eastern Europe, where it parasitizes wild Asteraceae species. It is also an important parasitic weed of sunflower crops. The objective of this research was to investigate genetic diversity, population structure, and virulence on sunflower of O. cumana populations parasitizing wild plants in eastern Bulgaria. Fresh tissue of eight O. cumana populations and mature seeds of four of them were collected in situ on wild hosts. Genetic diversity and population structure were studied with SSR markers and compared to weedy populations. Two main gene pools were identified in Bulgarian populations, with most of the populations having intermediate characteristics. Cross-inoculation experiments revealed that O. cumana populations collected on wild species possessed similar ability to parasitize sunflower to those collected on sunflower. The results were explained on the basis of an effective genetic exchange between populations parasitizing sunflower crops and those parasitizing wild species. The occurrence of bidirectional gene flow may have an impact on wild populations, as new physiological races continuously emerge in weedy populations. Also, genetic variability of wild populations may favour the ability of weedy populations to overcome sunflower resistance mechanisms.

The Genetic Structure of Wild Orobanche cumana Wallr. (Orobanchaceae) Populations in Eastern Bulgaria Reflects Introgressions from Weedy Populations

Science.gov (United States)

Pineda-Martos, Rocío; Pujadas-Salvà, Antonio J.; Fernández-Martínez, José M.; Stoyanov, Kiril; Pérez-Vich, Begoña

2014-01-01

Orobanche cumana is a holoparasitic plant naturally distributed from central Asia to south-eastern Europe, where it parasitizes wild Asteraceae species. It is also an important parasitic weed of sunflower crops. The objective of this research was to investigate genetic diversity, population structure, and virulence on sunflower of O. cumana populations parasitizing wild plants in eastern Bulgaria. Fresh tissue of eight O. cumana populations and mature seeds of four of them were collected in situ on wild hosts. Genetic diversity and population structure were studied with SSR markers and compared to weedy populations. Two main gene pools were identified in Bulgarian populations, with most of the populations having intermediate characteristics. Cross-inoculation experiments revealed that O. cumana populations collected on wild species possessed similar ability to parasitize sunflower to those collected on sunflower. The results were explained on the basis of an effective genetic exchange between populations parasitizing sunflower crops and those parasitizing wild species. The occurrence of bidirectional gene flow may have an impact on wild populations, as new physiological races continuously emerge in weedy populations. Also, genetic variability of wild populations may favour the ability of weedy populations to overcome sunflower resistance mechanisms. PMID:25143963

Biomonitoring a human population inhabiting nearby a deactivated uranium mine

International Nuclear Information System (INIS)

Lourenço, J.; Pereira, R.; Pinto, F.; Caetano, T.; Silva, A.; Carvalheiro, T.

2013-01-01

Highlights: ► Human population environmentally exposed to uranium mining wastes. ► Significantly higher levels of manganese and uranium in peripheral blood samples. ► Significant DNA damages detected by the comet assay. ► Significant decrease of NK and T lymphocytes counts in exposed individuals. ► Concerns on the risks of human populations living nearby uranium mining areas. - Abstract: Environmental exposure to uranium and its daughter radionuclides, has been linked to several negative effects such as those related with important physiological processes, like hematopoiesis, and may also be associated with genotoxicity effects. Herein, genotoxic effects, immunotoxicity, trace elements and C reactive protein (CRP) analyses, were performed in peripheral blood samples collected from individuals of a population living near a deactivated uranium mine. C reactive protein analysis was performed to exclude candidates with active inflammatory processes from further evaluations. DNA damage and immunotoxicity (immunophenotyping and immune cell counts) were evaluated by comet assay and flow cytometry, respectively. Significant DNA damage was observed in the peripheral blood samples from volunteers living in the Cunha Baixa village. A significant decrease of NK and T lymphocytes counts were observed in the individuals from the Cunha Baixa village, when compared with individuals from the reference site. Uranium and manganese levels were significantly higher in the Cunha Baixa village inhabitants. On the other hand, zinc levels were significantly lower in those individuals when compared with the volunteers from the control village. Results suggest that inhabitants from Cunha Baixa have a higher risk of suffering from serious diseases such as cancer, since high DNA damages were observed in peripheral blood leukocytes and also decreased levels of NK and T cells, which play an essential role in the defense against tumor growth

Synergistic efficacy of salicylic acid with a penetration enhancer on human skin monitored by OCT and diffuse reflectance spectroscopy

Science.gov (United States)

Zhao, Qingliang; Dai, Cuixia; Fan, Shanhui; Lv, Jing; Nie, Liming

2016-10-01

Salicylic acid (SA) has been frequently used as a facial chemical peeling agent (FCPA) in various cosmetics for facial rejuvenation and dermatological treatments in the clinic. However, there is a tradeoff between therapeutic effectiveness and possible adverse effects caused by this agent for cosmetologists. To optimize the cosmetic efficacy with minimal concentration, we proposed a chemical permeation enhancer (CPE) azone to synergistically work with SA on human skin in vivo. The optical properties of human skin after being treated with SA alone and SA combined with azone (SA@azone) were successively investigated by diffuse reflectance spectroscopy (DRS) and optical coherence tomography (OCT). Our results revealed that as the SA concentration increased, the light reflectance decreased and the absorption increased. We also found that SA@azone exhibited a synergistic effect on enhancing light penetration and OCT imaging depth. We demonstrated that the combination of DRS and OCT techniques could be used as a noninvasive, rapid and accurate measurement method to monitor the subtle changes of skin tissue after treatment with FCPA and CPE. The approach will greatly benefit the development of clinical cosmetic surgery, dermatosis diagnosis and therapeutic effect inspection in related biomedical studies.

Young Blood Rejuvenates Old Bodies: A Call for Reflection when Moving from Mice to Men.

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Hofmann, Bjørn

2018-01-01

Connecting the circulatory system of old and young mice (parabiosis) is documented to have rejuvenating effects on cells, tissues, organs, and functions. A wide range of benefits are envisioned. Blood-based rejuvenation can come to totally change population health and aging. The first blood rejuvenation studies on humans with Alzheimer's disease have started. It puts blood at the center of therapy and revitalizes the historical line of humoral pathology from Hippocrates and Harvey, creating a new type of 'bloodletting.' However, moving from mice to men requires careful consideration. Parabiosis actualizes well-known ethical challenges, such as just distribution of health care, avoiding disparities, and providing equal access to health care resources, as well as issues of human enhancement. However, it also poses new problems. Using internal substances in some persons as means to rejuvenate others calls for ethical reflection. New type of 'blood bonds' may result from the continuous demand for specific types of blood. Even if rejuvenating substances from blood may be artificially and cheaply produced and justly distributed, problems arise: survival may have to be balanced against reproduction, as reproductive age increases. Eternal youth and endless bliss have always been vital human dreams. Although parabiosis may bring us closer to the fountain of youth than ever, it is still too early to provide full-fledged assessments of its implications or to foresee how it will change health, aging, medicine, and society. However, in order to bring our reflective abilities on par with our technical skills, we need to start reflection now.

Metacognition: Effects on Reading Comprehension and Reflective Response.

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Barton, Valerie; Freeman, Barbara; Lewis, Dorothy; Thompson, Tamera

This report describes a project for increasing student's ability to comprehend and respond in a reflective manner. The targeted population consisted of 2nd, 3rd, and 5th grade classes in a community unit district located in a suburb of a large midwestern city. The problem of a student's inability to comprehend and respond in a reflective manner…

Measuring selection for genes that promote long life in a historical human population.

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Moorad, Jacob A; Walling, Craig A

2017-11-01

The unusually long lifespans of humans and the persistence of post-reproductive lifespans in women represent evolutionary puzzles because natural selection cannot directly favour continued living in post-menopausal women or elderly men. Suggested sources of indirect selection require genetic correlations between fitness and survival or reproduction at younger ages, reproduction in the opposite sex, or late-life contributions to offspring or grandoffspring fitness. Here we apply quantitative genetic analyses to data from a historical human population to explicitly test these evolutionary genetic hypotheses. Total genetic selection increased the male post-50 lifespans by 0.138 years per generation; 94% of this arose from indirect selection acting to favour early-life fitness in both sexes. These results argue strongly against life-history models of ageing that depend on trade-offs between reproduction and late-life survival. No source of indirect selection for female post-50 lifespan was detected, deepening the mystery of why female post-reproductive survival persists. This result is probably due to recent changes in the genetic architecture of female lifespan, and it highlights the need for similar quantitative genetic analyses of human populations at other points along demographic transitions.

Insights into Ancient Human Populations and their Environment through Stable Isotope Analysis

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Macko, S. A.

2011-12-01

Fundamental to the understanding of human history is the ability to make interpretations based on artifacts and other remains which are used to gather information about an ancient population. Sequestered in the organic matrices of these remains can be information concerning incidence of disease, population interactions, genetic defects and diet. Stable isotopes have long been used to interpret diet and trophic interactions in modern ecosystems. We suggest that the isotope compositions of a commonly overlooked material, human hair, is an ideal tool to be used in gleaning information, especially on human diets, about ancient civilizations. Hair can be well-preserved and is amenable to routine measurements of 13C, 15N and 34S isotope analyses and distinguishing sources of nutrition. We have isotopically characterized hair from both modern and ancient individuals. There is a wide diversity in isotope values owing, at least partially, to the levels of seafood, corn-fed animals and other grains in diet. Using these isotope tracers, new information regarding historical figures (George Washington, 1799 AD) to perhaps the most ancient of mummies, the Chinchorro of Chile (more than 7000 BP) as well as the Moche of Peru (1500 BP) and the best preserved mummy, the Neolithic Ice Man of the Oetztaler Alps (5200 BP), have been deciphered. It appears that the often-overlooked hair in archaeological sites represents a significant approach for understanding ancient human communities and their environments, as well as new perspectives on our use of our own modern nutritional sources.

Thermodynamics and Human Population

Science.gov (United States)

Cordry, Sean M.

2010-09-01

This paper discusses a Fermi-problem exercise through which I take students in several of my college courses. Students work in teams, determining the average daily Caloric needs per person. Then they use insolation values to determine the size of a collection area needed to absorb the previously determined daily energy requirements. Adjustments to the size of the collection area are made based on energy absorption per biological trophic level, as well as the consideration that most diets are a mixture of plant- and animal-derived elements. Finally, using the total amount of farmland available on the planet, students calculate a maximum population value. Although the maximum population values derived herewith should not be considered authoritative, the exercise has three beneficial purposes: 1) a chance to talk about the modeling process and extrapolations, 2) an unexpected application of physics to social contexts, and 3) raising student awareness of population and energy issues.

Automation-aided Task Loads Index based on the Automation Rate Reflecting the Effects on Human Operators in NPPs

International Nuclear Information System (INIS)

Lee, Seungmin; Seong, Poonghyun; Kim, Jonghyun

2013-01-01

Many researchers have found that a high automation rate does not guarantee high performance. Therefore, to reflect the effects of automation on human performance, a new estimation method of the automation rate that considers the effects of automation on human operators in nuclear power plants (NPPs) was suggested. These suggested measures express how much automation support human operators but it cannot express the change of human operators' workload, whether the human operators' workload is increased or decreased. Before considering automation rates, whether the adopted automation is good or bad might be estimated in advance. In this study, to estimate the appropriateness of automation according to the change of the human operators' task loads, automation-aided task loads index is suggested based on the concept of the suggested automation rate. To insure plant safety and efficiency on behalf of human operators, various automation systems have been installed in NPPs, and many works which were previously conducted by human operators can now be supported by computer-based operator aids. According to the characteristics of the automation types, the estimation method of the system automation and the cognitive automation rate were suggested. The proposed estimation method concentrates on the effects of introducing automation, so it directly express how much the automated system support human operators. Based on the suggested automation rates, the way to estimate how much the automated system can affect the human operators' cognitive task load is suggested in this study. When there is no automation, the calculated index is 1, and it means there is no change of human operators' task load

Gene Frequency and Heritability of Rh Blood Group Gene in 44 Human Populations

Directory of Open Access Journals (Sweden)

Supriyo CHAKRABORTY

2010-09-01

Full Text Available The frequency of RhD and Rhd alleles of Rh blood group gene was estimated in 44 human populations distributed all over the world from the RhD phenotypic data. The average frequency of RhD and Rhd allele over these populations was 0.70 and 0.30, respectively. Higher frequency of RhD allele than the expected estimate (0.50 in all the populations, under Hardy-Weinberg equilibrium condition assuming equal frequency of both alleles in the initial population, indicated inbreeding at RhD/d locus as well as natural selection for RhD allele. Very high heritability estimate (84.04% of Rh allele frequency revealed that this trait was under weak selection pressure and resulted in greater genetic variation in existing populations. It is consistent with Fishers fundamental theorem of natural selection. The results from the present study suggest that inbreeding at RhD/d locus and some other factors (possibly mutation, migration and genetic drift other than natural selection alone played major roles in changing the Rh allele frequency in these populations.

Management Education: Reflective Learning on Human Interaction

Science.gov (United States)

Clydesdale, Greg

2016-01-01

Purpose: This paper aims to describe an attempt to develop a more effective technique to teach self-awareness and relationship skills. Design/methodology/approach: A journal is used in combination with a model of human nature. The model lists human characteristics that the management trainee must identify in themselves and others they interact…

Association of common genetic variants with human skin color variation in Indian populations.

Science.gov (United States)

Sarkar, Anujit; Nandineni, Madhusudan R

2018-01-01

Human skin color is one of the most conspicuously variable physical traits that has attracted the attention of physical anthropologists, social scientists and human geneticists. Although several studies have established the underlying genes and their variants affecting human skin color, they were mostly confined to Europeans and Africans and similar studies in Indian populations have been scanty. Studying the association between candidate genetic variants and skin color will help to validate previous findings and to better understand the molecular mechanism of skin color variation. In this study, 22 candidate SNPs from 12 genes were tested for association with skin color in 299 unrelated samples sourced from nine geographical locations in India. Our study establishes the association of 9 SNPs with the phenotype in Indian populations and could explain ∼31% of the variance in skin color. Haplotype analysis of chromosome 15 revealed a significant association of alleles G, A and C of SNPs rs1426654, rs11070627, and rs12913316, respectively, to the phenotype, and accounted for 17% of the variance. Latitude of the sampling location was also a significant factor, contributing to ∼19% of the variation observed in the samples. These observations support the findings that rs1426654 and rs4775730 located in SLC24A5, and rs11070627 and rs12913316 located in MYEF2 and CTXN2 genes respectively, are major contributors toward skin pigmentation and would aid in further unraveling the genotype-phenotype association in Indian populations. These findings can be utilized in forensic DNA applications for criminal investigations. © 2017 Wiley Periodicals, Inc.

Diversity of human small intestinal Streptococcus and Veillonella populations.

Science.gov (United States)

van den Bogert, Bartholomeus; Erkus, Oylum; Boekhorst, Jos; de Goffau, Marcus; Smid, Eddy J; Zoetendal, Erwin G; Kleerebezem, Michiel

2013-08-01

Molecular and cultivation approaches were employed to study the phylogenetic richness and temporal dynamics of Streptococcus and Veillonella populations in the small intestine. Microbial profiling of human small intestinal samples collected from four ileostomy subjects at four time points displayed abundant populations of Streptococcus spp. most affiliated with S. salivarius, S. thermophilus, and S. parasanguinis, as well as Veillonella spp. affiliated with V. atypica, V. parvula, V. dispar, and V. rogosae. Relative abundances varied per subject and time of sampling. Streptococcus and Veillonella isolates were cultured using selective media from ileostoma effluent samples collected at two time points from a single subject. The richness of the Streptococcus and Veillonella isolates was assessed at species and strain level by 16S rRNA gene sequencing and genetic fingerprinting, respectively. A total of 160 Streptococcus and 37 Veillonella isolates were obtained. Genetic fingerprinting differentiated seven Streptococcus lineages from ileostoma effluent, illustrating the strain richness within this ecosystem. The Veillonella isolates were represented by a single phylotype. Our study demonstrated that the small intestinal Streptococcus populations displayed considerable changes over time at the genetic lineage level because only representative strains of a single Streptococcus lineage could be cultivated from ileostoma effluent at both time points. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Genomic validation of the differential preservation of population history in modern human cranial anatomy.

Science.gov (United States)

Reyes-Centeno, Hugo; Ghirotto, Silvia; Harvati, Katerina

2017-01-01

In modern humans, the significant correlation between neutral genetic loci and cranial anatomy suggests that the cranium preserves a population history signature. However, there is disagreement on whether certain parts of the cranium preserve this signature to a greater degree than other parts. It is also unclear how different quantitative measures of phenotype affect the association of genetic variation and anatomy. Here, we revisit these matters by testing the correlation of genetic distances and various phenotypic distances for ten modern human populations. Geometric morphometric shape data from the crania of adult individuals (n = 224) are used to calculate phenotypic P ST , Procrustes, and Mahalanobis distances. We calculate their correlation to neutral genetic distances, F ST , derived from single nucleotide polymorphisms (SNPs). We subset the cranial data into landmark configurations that include the neurocranium, the face, and the temporal bone in order to evaluate whether these cranial regions are differentially correlated to neutral genetic variation. Our results show that P ST , Mahalanobis, and Procrustes distances are correlated with F ST distances to varying degrees. They indicate that overall cranial shape is significantly correlated with neutral genetic variation. Of the component parts examined, P ST distances for both the temporal bone and the face have a stronger association with F ST distances than the neurocranium. When controlling for population divergence time, only the whole cranium and the temporal bone have a statistically significant association with F ST distances. Our results confirm that the cranium, as a whole, and the temporal bone can be used to reconstruct modern human population history. © 2016 Wiley Periodicals, Inc.

Human population, urban settlement patterns and their impact on Plasmodium falciparum malaria endemicity

Directory of Open Access Journals (Sweden)

Kabaria Caroline W

2008-10-01

Full Text Available Abstract Background The efficient allocation of financial resources for malaria control and the optimal distribution of appropriate interventions require accurate information on the geographic distribution of malaria risk and of the human populations it affects. Low population densities in rural areas and high population densities in urban areas can influence malaria transmission substantially. Here, the Malaria Atlas Project (MAP global database of Plasmodium falciparum parasite rate (PfPR surveys, medical intelligence and contemporary population surfaces are utilized to explore these relationships and other issues involved in combining malaria risk maps with those of human population distribution in order to define populations at risk more accurately. Methods First, an existing population surface was examined to determine if it was sufficiently detailed to be used reliably as a mask to identify areas of very low and very high population density as malaria free regions. Second, the potential of international travel and health guidelines (ITHGs for identifying malaria free cities was examined. Third, the differences in PfPR values between surveys conducted in author-defined rural and urban areas were examined. Fourth, the ability of various global urban extent maps to reliably discriminate these author-based classifications of urban and rural in the PfPR database was investigated. Finally, the urban map that most accurately replicated the author-based classifications was analysed to examine the effects of urban classifications on PfPR values across the entire MAP database. Results Masks of zero population density excluded many non-zero PfPR surveys, indicating that the population surface was not detailed enough to define areas of zero transmission resulting from low population densities. In contrast, the ITHGs enabled the identification and mapping of 53 malaria free urban areas within endemic countries. Comparison of PfPR survey results showed

Deadly heat waves projected in the densely populated agricultural regions of South Asia.

Science.gov (United States)

Im, Eun-Soon; Pal, Jeremy S; Eltahir, Elfatih A B

2017-08-01

The risk associated with any climate change impact reflects intensity of natural hazard and level of human vulnerability. Previous work has shown that a wet-bulb temperature of 35°C can be considered an upper limit on human survivability. On the basis of an ensemble of high-resolution climate change simulations, we project that extremes of wet-bulb temperature in South Asia are likely to approach and, in a few locations, exceed this critical threshold by the late 21st century under the business-as-usual scenario of future greenhouse gas emissions. The most intense hazard from extreme future heat waves is concentrated around densely populated agricultural regions of the Ganges and Indus river basins. Climate change, without mitigation, presents a serious and unique risk in South Asia, a region inhabited by about one-fifth of the global human population, due to an unprecedented combination of severe natural hazard and acute vulnerability.

Assessing radiologic risk for population due to human activities

International Nuclear Information System (INIS)

Toma, Al.; Dulama, C.; Dobrin, R.; Hirica, O.

2002-01-01

The most important factor in assessing radiologic risk is ensuring scientific means for evaluation of the radioactive release impact upon humans and organisms. To evaluate quantitatively this impact not only knowledge of radioactivity distribution in these dynamical systems is necessary but also understanding the transfer mechanisms between ecosystem components is needed. Thus a complete radioecologic study appear to be very complex and needs defining the source term, dynamic description of radionuclides behavior in the ecosystem, estimation of radiation doses in the major components of the ecosystem and finally the effects of radiation doses upon different parts of the systems. A diagram of the steps implied in evaluation of the effects due to radioactive effluent release in the environment is presented and discussed. The following steps are described: - identification of radioactive sources, as well as their input rate. Presence of noxious materials such as heavy metals or some organic compounds should be taken into account to assess the synergetic or antagonistic interactions; - determination of space-time distribution of release radionuclides; - estimation of dose rates and radiation exposure of population; - estimation of radiation dose effects upon individuals, population and ecosystems. This fourth step implies: experimental field or laboratory studies to determine the somatic/genetic response to radiation as a function of the exposure dose; following-up and interpretation of the organism response to dose or dose rates in terms of radiation-induce changes in the population life cycles; forecasting the irradiation effects upon population or communities within environment. Finally, this evaluation is completed by the decision making process implying a society acceptance of the forecast and/or observed effects

Variable ATP yields and uncoupling of oxygen consumption in human brain

DEFF Research Database (Denmark)

Gjedde, Albert; Aanerud, Joel; Peterson, Ericka

2011-01-01

normalized the metabolic rate to the population average of that region. Coefficients of variation ranged from 10 to 15% in the different regions of the human brain and the normalized regional metabolic rates ranged from 70% to 140% of the population average for each region, equal to a two-fold variation......The distribution of brain oxidative metabolism values among healthy humans is astoundingly wide for a measure that reflects normal brain function and is known to change very little with most changes of brain function. It is possible that the part of the oxygen consumption rate that is coupled...... to ATP turnover is the same in all healthy human brains, with different degrees of uncoupling explaining the variability of total oxygen consumption among people. To test the hypothesis that about 75% of the average total oxygen consumption of human brains is common to all individuals, we determined...

Ethical reflection and psychotherapy.

Science.gov (United States)

Vyskocilová, Jana; Prasko, Jan

2013-01-01

Theories of ethics and ethical reflection may be applied to both theory and practice in psychotherapy. There is a natural affinity between ethics and psychotherapy. Psychotherapy practice is concerned with human problems, dilemmas and emotions related to both one's own and other people's values. Ethics is also concerned with dilemmas in human thinking and with how these dilemmas reflect other individuals' values. Philosophical reflection itself is not a sufficient basis for the ethics of psychotherapy but it may aid in exploring attitudes related to psychotherapy, psychiatry and health care. PubMed, Web of Science and Scopus databases were searched for articles containing the keywords "psychotherapy", "ethics", "therapeutic relationship" and "supervision". The search was conducted by repeating the terms in various combinations without language or time restrictions. Also included were data from monographs cited in reviews. The resulting text is a review with conclusions concerning ethical aspects of psychotherapy. The ability to behave altruistically, sense for justice and reciprocity and mutual help are likely to be genetically determined as dispositions to be later developed by upbringing or to be formed or deformed by upbringing. Early experiences lead to formation of ethical attitudes which are internalized and then applied to both one's own and other people's behavior. Altruistic behavior has a strong impact on an individual's health and its acceptance may positively influence the pathophysiological mechanisms underlying numerous diseases. Ethical theory and reflection, however, may be applied to both theory and practice of psychotherapy in a conscious, targeted and thoughtful manner. In everyday practice, psychotherapists and organizations must necessarily deal with conscious conflicts between therapeutic possibilities, clients' wishes, their own as well as clients' ideas and the real world. Understanding one's own motives in therapy is one of the aims of a

Human Dignity, Misthanasia, Public Health and Bioethics in Brazil

Directory of Open Access Journals (Sweden)

Anna Silvia Penteado Setti da Rocha

2017-10-01

Full Text Available This paper aims to reflect on human dignity and misthanasia in the public health system in Brazil. For this, concepts, document reviews and public data about the condition of the Brazilian population’s access to public health were all used. The indicators show the health inequalities in the country, with the north and northeast at a disadvantage both in terms of access to health and the number of available professionals. Thus, the most underserved population tends to continue to be excluded from society and impaired with respect to their human dignity.

Beech Fructification and Bank Vole Population Dynamics--Combined Analyses of Promoters of Human Puumala Virus Infections in Germany.

Directory of Open Access Journals (Sweden)

Daniela Reil

Full Text Available The transmission of wildlife zoonoses to humans depends, amongst others, on complex interactions of host population ecology and pathogen dynamics within host populations. In Europe, the Puumala virus (PUUV causes nephropathia epidemica in humans. In this study we investigated complex interrelations within the epidemic system of PUUV and its rodent host, the bank vole (Myodes glareolus. We suggest that beech fructification and bank vole abundance are both decisive factors affecting human PUUV infections. While rodent host dynamics are expected to be directly linked to human PUUV infections, beech fructification is a rather indirect predictor by serving as food source for PUUV rodent hosts. Furthermore, we examined the dependence of bank vole abundance on beech fructification. We analysed a 12-year (2001-2012 time series of the parameters: beech fructification (as food resource for the PUUV host, bank vole abundance and human incidences from 7 Federal States of Germany. For the first time, we could show the direct interrelation between these three parameters involved in human PUUV epidemics and we were able to demonstrate on a large scale that human PUUV infections are highly correlated with bank vole abundance in the present year, as well as beech fructification in the previous year. By using beech fructification and bank vole abundance as predictors in one model we significantly improved the degree of explanation of human PUUV incidence. Federal State was included as random factor because human PUUV incidence varies considerably among states. Surprisingly, the effect of rodent abundance on human PUUV infections is less strong compared to the indirect effect of beech fructification. Our findings are useful to facilitate the development of predictive models for host population dynamics and the related PUUV infection risk for humans and can be used for plant protection and human health protection purposes.

Human papillomavirus prevalence and type distribution in 3603 HIV-positive and HIV-negative women in the general population of Tanzania

DEFF Research Database (Denmark)

Dartell, Myassa Arkam; Rasch, Vibeke; Kahesa, Crispin

2012-01-01

The aim of the Prevention of Cervical Cancer in Tanzania (PROTECT) study is to assess the prevalence of oncogenic human papillomavirus (HPV) and to determine the type distribution among women in the general population according to human immunodeficiency virus (HIV) status, in preparation for a po......The aim of the Prevention of Cervical Cancer in Tanzania (PROTECT) study is to assess the prevalence of oncogenic human papillomavirus (HPV) and to determine the type distribution among women in the general population according to human immunodeficiency virus (HIV) status, in preparation...

Reflective journal writing: how it promotes reflective thinking in clinical nursing education: a students' perspective.

Science.gov (United States)

Kok, J; Chabeli, M M

2002-08-01

According to the outcomes-based education and training system of education (OBET) in the country and the South African Nursing Council, education should focus on "creating" reflective learners and practitioners. This article seeks to determine the effectiveness of reflective journal writing in promoting the reflective thinking of learners in clinical nursing education and to validate the guidelines described in a bigger study on how to facilitate reflective thinking using reflective journal writing. A qualitative, contextual, explorative, descriptive research design was used to determine the learners' perceptions on whether reflective journal writing did promote their higher-level thinking skills during the six-month placement in a psychiatric clinical practice using the reflective diaries. From a population of seventeen fourth-year students, six volunteered to participate in a focus group interview. The data was analysed by means of the descriptive method of open coding of Tesch (in Creswell, 1994:154-156). Positive and negative results from the perceptions of the participants and a literature review served as a basis for deducing and describing guidelines for the effective use of reflective journal writing in promoting reflective thinking in clinical nursing education. The positive perception was the development of problem-solving skills attained through reflection by using analytical critical thinking, synthesis and the evaluation of situations. Self-evaluation leading to intellectual growth and self-awareness indicated a positive perception. Negative perceptions were that reflective journal writing is time consuming, content based with a lack of clear expectations from the teacher, and distrust of students about the information written. Guba's model of ensuring trustworthiness in qualitative research as described in Krefting (1991:215-222) was employed. It is concluded that reflective journal writing in clinical nursing education does promote reflective

Radiation protection for human population

International Nuclear Information System (INIS)

Kenigsberg, Ya.Eh.; Bogdevich, I.M.; Rolevich, I.V.; Sharovarov, G.A.; Skurat, V.V.

1997-01-01

Are given the results of researches carried out in Belarus in 1996 on the following directions: study of features of formation of the population irradiation doze; definition of collective irradiation dozes of the population of Belarus for 10 years after the Chernobyl accident and forecast of risk of radiation induced diseases; study of influence of the radioactive contamination on agricultural ecosystems; development of technologies of manufacture on the contaminated soils of plant and cattle-breeding production and food products with the permissible contents of radionuclides in according to the requirements of radiation protection; development and perfection of complex technologies, ways and means of decontamination, processing and burial of radioactive wastes; development and substantiation of actions for increase of radiation security of the population of Belarus; development of combined system of an estimation on problems of radiation protection of the population living on contaminated territories

High-throughput telomere length quantification by FISH and its application to human population studies.

Science.gov (United States)

Canela, Andrés; Vera, Elsa; Klatt, Peter; Blasco, María A

2007-03-27

A major limitation of studies of the relevance of telomere length to cancer and age-related diseases in human populations and to the development of telomere-based therapies has been the lack of suitable high-throughput (HT) assays to measure telomere length. We have developed an automated HT quantitative telomere FISH platform, HT quantitative FISH (Q-FISH), which allows the quantification of telomere length as well as percentage of short telomeres in large human sample sets. We show here that this technique provides the accuracy and sensitivity to uncover associations between telomere length and human disease.

Automation-aided Task Loads Index based on the Automation Rate Reflecting the Effects on Human Operators in NPPs

Energy Technology Data Exchange (ETDEWEB)

Lee, Seungmin; Seong, Poonghyun [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Kim, Jonghyun [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

2013-05-15

Many researchers have found that a high automation rate does not guarantee high performance. Therefore, to reflect the effects of automation on human performance, a new estimation method of the automation rate that considers the effects of automation on human operators in nuclear power plants (NPPs) was suggested. These suggested measures express how much automation support human operators but it cannot express the change of human operators' workload, whether the human operators' workload is increased or decreased. Before considering automation rates, whether the adopted automation is good or bad might be estimated in advance. In this study, to estimate the appropriateness of automation according to the change of the human operators' task loads, automation-aided task loads index is suggested based on the concept of the suggested automation rate. To insure plant safety and efficiency on behalf of human operators, various automation systems have been installed in NPPs, and many works which were previously conducted by human operators can now be supported by computer-based operator aids. According to the characteristics of the automation types, the estimation method of the system automation and the cognitive automation rate were suggested. The proposed estimation method concentrates on the effects of introducing automation, so it directly express how much the automated system support human operators. Based on the suggested automation rates, the way to estimate how much the automated system can affect the human operators' cognitive task load is suggested in this study. When there is no automation, the calculated index is 1, and it means there is no change of human operators' task load.

Determination of fluoride in human nails via cyclic instrumental neutron activation analysis

International Nuclear Information System (INIS)

Spate, V.L.; Morris, J.S.; Baskett, C.K.; Mason, M.M.; Reams, C.L.

1994-01-01

The role of fluorine in human health has become somewhat controversial. It is widely accepted as protective against dental caries, may be protective against osteoporosis, and has been very conservatively implicated with osteosarcoma in male rats. The develepment of a neutron activation analysis method and its application to the analysis of human nails is reported. It has been found that toenails collected in population-based epidemiology studies apparently reflect fluoride intake. (author) 11 refs.; 2 tabs

Social learning and human mate preferences: a potential mechanism for generating and maintaining between-population diversity in attraction

Science.gov (United States)

Little, Anthony C.; Jones, Benedict C.; DeBruine, Lisa M.; Caldwell, Christine A.

2011-01-01

Inspired by studies demonstrating mate-choice copying effects in non-human species, recent studies of attractiveness judgements suggest that social learning also influences human preferences. In the first part of our article, we review evidence for social learning effects on preferences in humans and other animals. In the second part, we present new empirical evidence that social learning not only influences the attractiveness of specific individuals, but can also generalize to judgements of previously unseen individuals possessing similar physical traits. The different conditions represent different populations and, once a preference arises in a population, social learning can lead to the spread of preferences within that population. In the final part of our article, we discuss the theoretical basis for, and possible impact of, biases in social learning whereby individuals may preferentially copy the choices of those with high status or better access to critical information about potential mates. Such biases could mean that the choices of a select few individuals carry the greatest weight, rapidly generating agreement in preferences within a population. Collectively, these issues suggest that social learning mechanisms encourage the spread of preferences for certain traits once they arise within a population and so may explain certain cross-cultural differences. PMID:21199841

Population genetic structure of the endemic rosewoods Dalbergia cochinchinensis and D. oliveri at a regional scale reflects the Indochinese landscape and life-history traits

DEFF Research Database (Denmark)

Hartvig, Ida; So, Thea; Changtragoon, Suchitra

2018-01-01

of the distribution area, particularly in Cambodia. We suggest that this pattern is ancient, reflecting the demographic history of the species and possible location of refugia during earlier time periods with limited forest cover, which was supported by signs of old genetic bottlenecks. The D. oliveri populations had......Indochina is a biodiversity hot spot and harbors a high number of endemic species, most of which are poorly studied. This study explores the genetic structure and reproductive system of the threatened endemic timber species Dalbergia cochinchinensis and Dalbergia oliveri using microsatellite data...... from populations across Indochina and relates it to landscape characteristics and life-history traits. We found that the major water bodies in the region, Mekong and Tonle Sap, represented barriers to gene flow and that higher levels of genetic diversity were found in populations in the center...

The Hiroshima Experience: Two Reflections.

Science.gov (United States)

Enloe, Walter; Cogan, John

1985-01-01

The bombing of Hiroshima changed forever the concept of conflict and warfare in the human family. Two Americans, one having grown up in Hiroshima and the other having spent one year in the city as a Fullbright research scholar, reflect on the Hiroshima experience. (RM)

A Soil Service Index: Potential Soil Services to Society under Scenarios of Human Land Use and Population Growth

Science.gov (United States)

Hugelius, G.; Ahlström, A.; Loisel, J.; Harden, J. W.

2017-12-01

Soils provide numerous and indispensable services to ecological systems and human societies. As human populations and human land use changes, the capacity of soils to maintain these services may also change. To investigate this we provide the first global scale study based on the soil service index (SSI; see presentations by Harden et al. and Loisel et al. in this session for more details). In this index multiple soil services are numerically or quantitatively assessed, normalized to a unit-less scale for purposes of intercomparability. Soil services assessed under the SSI include organic matter and/or organic carbon storage; plant productivity; CO2 or GHG exchange with the atmosphere; water storage capacity; and nutrient storage and/or availability. The SSI may be applied at any scale. Here we present a first global application of the SSI and provide broad-scale analyses of soil service spatial distributions. We assess how the SSI will change under projected changes in human societies populations and human land use (following representative concentration pathway scenarios). Present and future potential utilization and vulnerability of soil resources are analyzed in the context of human population distributions and its projected changes. The SSI is designed to be broadly useful across scientific, governance and resource management organizations. To exemplify this, the parameterization of this is global soil service estimate is based on only open source input data.

Reflecting reflection in supervision

DEFF Research Database (Denmark)

Lystbæk, Christian Tang

associated with reflection and an exploration of alternative conceptions that view reflection within the context of settings which have a more group- and team-based orientation. Drawing on an action research project on health care supervision, the paper questions whether we should reject earlier views...... of reflection, rehabilitate them in order to capture broader connotations or move to new ways of regarding reflection that are more in keeping with not only reflective but also emotive, normative and formative views on supervision. The paper presents a critical perspective on supervision that challenge...... the current reflective paradigm I supervision and relate this to emotive, normative and formative views supervision. The paper is relevant for Nordic educational research into the supervision and guidance...

Human bony labyrinth is an indicator of population history and dispersal from Africa.

Science.gov (United States)

Ponce de León, Marcia S; Koesbardiati, Toetik; Weissmann, John David; Milella, Marco; Reyna-Blanco, Carlos S; Suwa, Gen; Kondo, Osamu; Malaspinas, Anna-Sapfo; White, Tim D; Zollikofer, Christoph P E

2018-04-17

The dispersal of modern humans from Africa is now well documented with genetic data that track population history, as well as gene flow between populations. Phenetic skeletal data, such as cranial and pelvic morphologies, also exhibit a dispersal-from-Africa signal, which, however, tends to be blurred by the effects of local adaptation and in vivo phenotypic plasticity, and that is often deteriorated by postmortem damage to skeletal remains. These complexities raise the question of which skeletal structures most effectively track neutral population history. The cavity system of the inner ear (the so-called bony labyrinth) is a good candidate structure for such analyses. It is already fully formed by birth, which minimizes postnatal phenotypic plasticity, and it is generally well preserved in archaeological samples. Here we use morphometric data of the bony labyrinth to show that it is a surprisingly good marker of the global dispersal of modern humans from Africa. Labyrinthine morphology tracks genetic distances and geography in accordance with an isolation-by-distance model with dispersal from Africa. Our data further indicate that the neutral-like pattern of variation is compatible with stabilizing selection on labyrinth morphology. Given the increasingly important role of the petrous bone for ancient DNA recovery from archaeological specimens, we encourage researchers to acquire 3D morphological data of the inner ear structures before any invasive sampling. Such data will constitute an important archive of phenotypic variation in present and past populations, and will permit individual-based genotype-phenotype comparisons. Copyright © 2018 the Author(s). Published by PNAS.

Trends in mortality and biological stress in a medieval polish urban population.

Science.gov (United States)

Betsinger, Tracy K; DeWitte, Sharon

2017-12-01

Urbanization in pre-modern populations may have had a variety of consequences related to population crowding. However, research on the effects of urbanization have provided inconsistent results regarding the biological impact of this transition on human populations. The purpose of this study is to test the hypothesis that urbanization caused an increase in overall biological stress in a medieval (10th-13th centuries AD) Polish population. A human skeletal sample (n=164) was examined for the presence of porotic hyperostosis, cribra orbitalia, linear enamel hypoplasia, periosteal reaction, and specific infectious diseases. Prevalence rates were compared among three temporal samples: initial urbanization, early urbanization, and later urbanization. Results indicate no significant trends for any of the pathological conditions. Cox proportional hazards analyses, however, revealed a significant increase in the risk of death over time, which supports the hypothesis. These results reflect the necessity of using multiple analyses to address bioarchaeological questions. The lack of significant results from skeletal indicators may be due to an earlier urbanization trend in the population. This study illustrates that the association of urbanization with elevated biological stress is complicated and dependent on various factors, including culture and time period. Copyright © 2017 Elsevier Inc. All rights reserved.

Optimising land use and consumption of livestock products in the human diet with an increasing human population in the Netherlands

NARCIS (Netherlands)

Kernebeek, van H.R.J.; Oosting, S.J.; Ittersum, van M.K.; Boer, de I.J.M.

2014-01-01

Land use related to food production is generally quantified using product-based life cycle assessments. We, however, quantified land use of diet scenarios with a land use optimization model. Energy and protein requirement of human populations, varying from 15 to 30 mil-lion people, were met with the

Wolf population dynamics in the U.S. Northern Rocky Mountains are affected by recruitment and human-caused mortality

Science.gov (United States)

Gude, J.A.; Mitchell, M.S.; Russell, R.E.; Sime, C.A.; Bangs, E.E.; Mech, L.D.; Ream, R.R.

2012-01-01

Reliable analyses can help wildlife managers make good decisions, which are particularly critical for controversial decisions such as wolf (Canis lupus) harvest. Creel and Rotella (2010) recently predicted substantial population declines in Montana wolf populations due to harvest, in contrast to predictions made by Montana Fish, Wildlife and Parks (MFWP). We replicated their analyses considering only those years in which field monitoring was consistent, and we considered the effect of annual variation in recruitment on wolf population growth. Rather than assuming constant rates, we used model selection methods to evaluate and incorporate models of factors driving recruitment and human-caused mortality rates in wolf populations in the Northern Rocky Mountains. Using data from 27 area-years of intensive wolf monitoring, we show that variation in both recruitment and human-caused mortality affect annual wolf population growth rates and that human-caused mortality rates have increased with the sizes of wolf populations. We document that recruitment rates have decreased over time, and we speculate that rates have decreased with increasing population sizes and/or that the ability of current field resources to document recruitment rates has recently become less successful as the number of wolves in the region has increased. Estimates of positive wolf population growth in Montana from our top models are consistent with field observations and estimates previously made by MFWP for 2008-2010, whereas the predictions for declining wolf populations of Creel and Rotella (2010) are not. Familiarity with limitations of raw data, obtained first-hand or through consultation with scientists who collected the data, helps generate more reliable inferences and conclusions in analyses of publicly available datasets. Additionally, development of efficient monitoring methods for wolves is a pressing need, so that analyses such as ours will be possible in future years when fewer resources

Progress and Challenges in Developing Reference Data Layers for Human Population Distribution and Built Infrastructure

Science.gov (United States)

Chen, R. S.; Yetman, G.; de Sherbinin, A. M.

2015-12-01

Understanding the interactions between environmental and human systems, and in particular supporting the applications of Earth science data and knowledge in place-based decision making, requires systematic assessment of the distribution and dynamics of human population and the built human infrastructure in conjunction with environmental variability and change. The NASA Socioeconomic Data and Applications Center (SEDAC) operated by the Center for International Earth Science Information Network (CIESIN) at Columbia University has had a long track record in developing reference data layers for human population and settlements and is expanding its efforts on topics such as intercity roads, reservoirs and dams, and energy infrastructure. SEDAC has set as a strategic priority the acquisition, development, and dissemination of data resources derived from remote sensing and socioeconomic data on urban land use change, including temporally and spatially disaggregated data on urban change and rates of change, the built infrastructure, and critical facilities. We report here on a range of past and ongoing activities, including the Global Human Settlements Layer effort led by the European Commission's Joint Research Centre (JRC), the Global Exposure Database for the Global Earthquake Model (GED4GEM) project, the Global Roads Open Access Data Working Group (gROADS) of the Committee on Data for Science and Technology (CODATA), and recent work with ImageCat, Inc. to improve estimates of the exposure and fragility of buildings, road and rail infrastructure, and other facilities with respect to selected natural hazards. New efforts such as the proposed Global Human Settlement indicators initiative of the Group on Earth Observations (GEO) could help fill critical gaps and link potential reference data layers with user needs. We highlight key sectors and themes that require further attention, and the many significant challenges that remain in developing comprehensive, high quality

Human genetics of infectious diseases: a unified theory

Science.gov (United States)

Casanova, Jean-Laurent; Abel, Laurent

2007-01-01

Since the early 1950s, the dominant paradigm in the human genetics of infectious diseases postulates that rare monogenic immunodeficiencies confer vulnerability to multiple infectious diseases (one gene, multiple infections), whereas common infections are associated with the polygenic inheritance of multiple susceptibility genes (one infection, multiple genes). Recent studies, since 1996 in particular, have challenged this view. A newly recognised group of primary immunodeficiencies predisposing the individual to a principal or single type of infection is emerging. In parallel, several common infections have been shown to reflect the inheritance of one major susceptibility gene, at least in some populations. This novel causal relationship (one gene, one infection) blurs the distinction between patient-based Mendelian genetics and population-based complex genetics, and provides a unified conceptual frame for exploring the molecular genetic basis of infectious diseases in humans. PMID:17255931

Population Pharmacokinetics of Tenofovir in Human Immunodeficiency Virus-Infected Patients Taking Highly Active Antiretroviral Therapy

OpenAIRE

Jullien, Vincent; Tréluyer, Jean-Marc; Rey, Elisabeth; Jaffray, Patrick; Krivine, Anne; Moachon, Laurence; Lillo-Le Louet, Agnès; Lescoat, Anne; Dupin, Nicolas; Salmon, Dominique; Pons, Gérard; Urien, Saïk

2005-01-01

The influence of renal function on tenofovir pharmacokinetics was investigated in 193 human immunodeficiency virus (HIV)-infected patients by the use of a population approach performed with the nonlinear mixed effects modeling program NONMEM. Tenofovir pharmacokinetics was well described by a two-compartment open model in which the absorption and the distribution rate constants are equal. Typical population estimates of apparent central distribution volume (Vc/F), peripheral distribution volu...

Exoskeleton master controller with force-reflecting telepresence

Science.gov (United States)

Burke, James B.; Bartholet, Stephen J.; Nelson, David K.

1992-01-01

A thorough understanding of the requirements for successful master-slave robotic systems is becoming increasingly desirable. Such systems can aid in the accomplishment of tasks that are hazardous or inaccessible to humans. Although a history of use has proven master-slave systems to be viable, system requirements and the impact of specifications on the human factors side of system performance are not well known. In support of the next phase of teleoperation research being conducted at the Armstrong Research Laboratory, a force-reflecting, seven degree of freedom exoskeleton for master-slave teleoperation has been concepted, and is presently being developed. The exoskeleton has a unique kinematic structure that complements the structure of the human arm. It provides a natural means for teleoperating a dexterous, possibly redundant manipulator. It allows ease of use without operator fatigue and faithfully follows human arm and wrist motions. Reflected forces and moments are remotely transmitted to the operator hand grip using a cable transmission scheme. This paper presents the exoskeleton concept and development results to date. Conceptual design, hardware, algorithms, computer architecture, and software are covered.

Inspiring Reflections

DEFF Research Database (Denmark)

Muchie, Mammo

2011-01-01

A numberof Chris Freeman's colleagues were asked to reflect on what they thought describes his life and work in a few words. Some of the colleagues replied including former SPRU students that were taught or supervised by Chris Freeman. Their views on what they thought were Chris Freeman's defining...... life is not free from fluctuations, cycles, disruptions, crises and destructions both human and ecological. Innovation research ought to position itself to address environmental, financial and economic crises. The third is innovation research for development by addressing not only poverty erdaication...

Human Populations and the World Conservation Strategy. Commission on Ecology Paper Number 11.

Science.gov (United States)

Hanks, J.

This document serves as a supplement to the World Conservation Strategy (WCS) and outlines some of the critical aspects of the interaction between human populations, natural resources, and social and economic conditions. Particular emphasis is placed on the importance of planning with people, and on packaging conservation programs so they are more…

Phylodynamics of Merkel-cell polyomavirus and human polyomavirus 6: A long-term history with humans.

Science.gov (United States)

Torres, Carolina; Barrios, Melina Elizabeth; Cammarata, Robertina Viviana; Victoria, Matías; Fernandez-Cassi, Xavier; Bofill-Mas, Silvia; Colina, Rodney; Blanco Fernández, María Dolores; Mbayed, Viviana Andrea

2018-04-20

New human polyomaviruses have been described in the last years, including the Merkel-cell polyomavirus (MCPyV; Human polyomavirus 5) and the Human polyomavirus 6 (HPyV6). Although their infection is usually asymptomatic, in immunocompromised host can cause life-threatening pathologies, such as the Merkel cell carcinoma, an aggressive skin neoplasia associated to the MCPyV. Despite being prevalent viruses in population, epidemiological data from South America are scarce, as well as the characterization of the viral types circulating and their origin. The aims of this work were to describe MCPyV and HPyV6 from environmental samples with different geographical origin and to analyze their phylogenetic and evolutionary histories, particularly for MCPyV. Partial and complete genome sequences were obtained from sewage samples from Argentina, Uruguay and Spain. A total number of 87 sequences were obtained for MCPyV and 33 for HPyV6. Phylogenetic analysis showed that MCPyV sequences distributed according to their geographic origin in Europe/North America, Africa, Asia, South America and Oceania groups, suggesting that viral diversification might have followed human migrations across the globe. In particular, viruses from Argentina associated with Europe/North America and South America genotypes, whereas those from Uruguay and Spain also grouped with Africa genotype, reflecting the origin of the current population in each country, which could arrive not only during ancient human migration but also during recent migratory events. In addition, the South American group presented a high level of clusterization, showing internal clusters that could be related to specific locations, such as French Guiana and Brazil or the Southern region into South America, such as Argentina and Uruguay, suggesting a long term evolutionary process in the region. Additionally, in this work, we carried out the first analysis about the evolutionary history of MCPyV trough the integration of

Inference of population splits and mixtures from genome-wide allele frequency data.

Directory of Open Access Journals (Sweden)

Joseph K Pickrell

Full Text Available Many aspects of the historical relationships between populations in a species are reflected in genetic data. Inferring these relationships from genetic data, however, remains a challenging task. In this paper, we present a statistical model for inferring the patterns of population splits and mixtures in multiple populations. In our model, the sampled populations in a species are related to their common ancestor through a graph of ancestral populations. Using genome-wide allele frequency data and a Gaussian approximation to genetic drift, we infer the structure of this graph. We applied this method to a set of 55 human populations and a set of 82 dog breeds and wild canids. In both species, we show that a simple bifurcating tree does not fully describe the data; in contrast, we infer many migration events. While some of the migration events that we find have been detected previously, many have not. For example, in the human data, we infer that Cambodians trace approximately 16% of their ancestry to a population ancestral to other extant East Asian populations. In the dog data, we infer that both the boxer and basenji trace a considerable fraction of their ancestry (9% and 25%, respectively to wolves subsequent to domestication and that East Asian toy breeds (the Shih Tzu and the Pekingese result from admixture between modern toy breeds and "ancient" Asian breeds. Software implementing the model described here, called TreeMix, is available at http://treemix.googlecode.com.

Medial prefrontal cortex subserves diverse forms of self-reflection.

Science.gov (United States)

Jenkins, Adrianna C; Mitchell, Jason P

2011-01-01

The ability to think about oneself--to self--reflect--is one of the defining features of the human mind. Recent research has suggested that this ability may be subserved by a particular brain region: the medial prefrontal cortex (MPFC). However, although humans can contemplate a variety of different aspects of themselves, including their stable personality traits, current feelings, and physical attributes, no research has directly examined the extent to which these different forms of self-reflection are subserved by common mechanisms. To address this question, participants were scanned using functional magnetic resonance imaging (fMRI) while making judgments about their own personality traits, current mental states, and physical attributes as well as those of another person. Whereas some brain regions responded preferentially during only one form of self-reflection, a robust region of MPFC was engaged preferentially during self-reflection across all three types of judgment. These results suggest that--although dissociable--diverse forms of self-referential thought draw on a shared cognitive process subserved by MPFC.

Can your country make you sick? Multi-level explorations of population health and human rights in a global perspective

NARCIS (Netherlands)

Witvliet, M.I.

2013-01-01

Research investigating health and human rights from a socio-epidemiological perspective is emerging. Still there is a noticeable paucity of research that empirically links population health to human rights concerns. In this thesis, three examples relevant to human rights are explored. We investigate

Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

International Nuclear Information System (INIS)

Fabrikant, J.I.

1981-01-01

The present review provides an understanding of our current knowledge of the carcinogenic effect of low-dose radiation in man, and surveys the epidemiological studies of human populations exposed to nuclear explosions and medical radiation. Discussion centers on the contributions of quantitative epidemiology to present knowledge, the reliability of the dose-incidence data, and those relevant epidemiological studies that provide the most useful information for risk estimation of cancer induction in man. Reference is made to dose-incidence relationships from laboratory animal experiments where they may obtain, for problems and difficulties in extrapolation from data obtained at high doses to low doses, and from animal data to the human situation. The paper describes the methods of application of such epidemiological data for estimation of excess risk of radiation-induced cancer in exposed human populations and discusses the strengths and limitations of epidemiology in guiding radiation protection philosophy and public health policy

Interactions between thalamic and cortical rhythms during semantic memory recall in human

Science.gov (United States)

Slotnick, Scott D.; Moo, Lauren R.; Kraut, Michael A.; Lesser, Ronald P.; Hart, John, Jr.

2002-04-01

Human scalp electroencephalographic rhythms, indicative of cortical population synchrony, have long been posited to reflect cognitive processing. Although numerous studies employing simultaneous thalamic and cortical electrode recording in nonhuman animals have explored the role of the thalamus in the modulation of cortical rhythms, direct evidence for thalamocortical modulation in human has not, to our knowledge, been obtained. We simultaneously recorded from thalamic and scalp electrodes in one human during performance of a cognitive task and found a spatially widespread, phase-locked, low-frequency rhythm (7-8 Hz) power decrease at thalamus and scalp during semantic memory recall. This low-frequency rhythm power decrease was followed by a spatially specific, phase-locked, fast-rhythm (21-34 Hz) power increase at thalamus and occipital scalp. Such a pattern of thalamocortical activity reflects a plausible neural mechanism underlying semantic memory recall that may underlie other cognitive processes as well.

Simultaneous determination of CRP and D-dimer in human blood plasma samples with White Light Reflectance Spectroscopy.

Science.gov (United States)

Koukouvinos, Georgios; Petrou, Panagiota; Misiakos, Konstantinos; Drygiannakis, Dimitris; Raptis, Ioannis; Stefanitsis, Gerasimos; Martini, Spyridoula; Nikita, Dimitra; Goustouridis, Dimitrios; Moser, Isabella; Jobst, Gerhard; Kakabakos, Sotirios

2016-10-15

A dual-analyte assay for the simultaneous determination of C-reactive protein (CRP) and D-dimer in human blood plasma based on a white light interference spectroscopy sensing platform is presented. Measurement is accomplished in real-time by scanning the sensing surface, on which distinct antibody areas have been created, with a reflection probe used both for illumination of the surface and collection of the reflected interference spectrum. The composition of the transducer, the sensing surface chemical activation and biofunctionalization procedures were optimized with respect to signal magnitude and repeatability. The assay format involved direct detection of CRP whereas for D-dimer a two-site immunoassay employing a biotinylated reporter antibody and reaction with streptavidin was selected. The assays were sensitive with detection limits of 25ng/mL for both analytes, precise with intra- and inter-assay CV values ranging from 3.6% to 7.7%, and from 4.8% to 9.5%, respectively, for both assays, and accurate with recovery values ranging from 88.5% to 108% for both analytes. Moreover, the values determined for the two analytes in 35 human plasma samples were in excellent agreement with those received for the same samples by standard diagnostic laboratory instrumentation employing commercial kits. The excellent agreement of the results supported the validity of the proposed system for clinical application for the detection of multiple analytes since it was demonstrated that up to seven antibody areas can be created on the sensing surface and successfully interrogated with the developed optical set-up. Copyright © 2015. Published by Elsevier B.V.

Ancient human genomes suggest three ancestral populations for present-day Europeans

Science.gov (United States)

Lazaridis, Iosif; Patterson, Nick; Mittnik, Alissa; Renaud, Gabriel; Mallick, Swapan; Kirsanow, Karola; Sudmant, Peter H.; Schraiber, Joshua G.; Castellano, Sergi; Lipson, Mark; Berger, Bonnie; Economou, Christos; Bollongino, Ruth; Fu, Qiaomei; Bos, Kirsten I.; Nordenfelt, Susanne; Li, Heng; de Filippo, Cesare; Prüfer, Kay; Sawyer, Susanna; Posth, Cosimo; Haak, Wolfgang; Hallgren, Fredrik; Fornander, Elin; Rohland, Nadin; Delsate, Dominique; Francken, Michael; Guinet, Jean-Michel; Wahl, Joachim; Ayodo, George; Babiker, Hamza A.; Bailliet, Graciela; Balanovska, Elena; Balanovsky, Oleg; Barrantes, Ramiro; Bedoya, Gabriel; Ben-Ami, Haim; Bene, Judit; Berrada, Fouad; Bravi, Claudio M.; Brisighelli, Francesca; Busby, George B. J.; Cali, Francesco; Churnosov, Mikhail; Cole, David E. C.; Corach, Daniel; Damba, Larissa; van Driem, George; Dryomov, Stanislav; Dugoujon, Jean-Michel; Fedorova, Sardana A.; Romero, Irene Gallego; Gubina, Marina; Hammer, Michael; Henn, Brenna M.; Hervig, Tor; Hodoglugil, Ugur; Jha, Aashish R.; Karachanak-Yankova, Sena; Khusainova, Rita; Khusnutdinova, Elza; Kittles, Rick; Kivisild, Toomas; Klitz, William; Kučinskas, Vaidutis; Kushniarevich, Alena; Laredj, Leila; Litvinov, Sergey; Loukidis, Theologos; Mahley, Robert W.; Melegh, Béla; Metspalu, Ene; Molina, Julio; Mountain, Joanna; Näkkäläjärvi, Klemetti; Nesheva, Desislava; Nyambo, Thomas; Osipova, Ludmila; Parik, Jüri; Platonov, Fedor; Posukh, Olga; Romano, Valentino; Rothhammer, Francisco; Rudan, Igor; Ruizbakiev, Ruslan; Sahakyan, Hovhannes; Sajantila, Antti; Salas, Antonio; Starikovskaya, Elena B.; Tarekegn, Ayele; Toncheva, Draga; Turdikulova, Shahlo; Uktveryte, Ingrida; Utevska, Olga; Vasquez, René; Villena, Mercedes; Voevoda, Mikhail; Winkler, Cheryl; Yepiskoposyan, Levon; Zalloua, Pierre; Zemunik, Tatijana; Cooper, Alan; Capelli, Cristian; Thomas, Mark G.; Ruiz-Linares, Andres; Tishkoff, Sarah A.; Singh, Lalji; Thangaraj, Kumarasamy; Villems, Richard; Comas, David; Sukernik, Rem; Metspalu, Mait; Meyer, Matthias; Eichler, Evan E.; Burger, Joachim; Slatkin, Montgomery; Pääbo, Svante; Kelso, Janet; Reich, David; Krause, Johannes

2014-01-01

We sequenced the genomes of a ~7,000 year old farmer from Germany and eight ~8,000 year old hunter-gatherers from Luxembourg and Sweden. We analyzed these and other ancient genomes1–4 with 2,345 contemporary humans to show that most present Europeans derive from at least three highly differentiated populations: West European Hunter-Gatherers (WHG), who contributed ancestry to all Europeans but not to Near Easterners; Ancient North Eurasians (ANE) related to Upper Paleolithic Siberians3, who contributed to both Europeans and Near Easterners; and Early European Farmers (EEF), who were mainly of Near Eastern origin but also harbored WHG-related ancestry. We model these populations’ deep relationships and show that EEF had ~44% ancestry from a “Basal Eurasian” population that split prior to the diversification of other non-African lineages. PMID:25230663

A map of human genome variation from population-scale sequencing.

Science.gov (United States)

Abecasis, Gonçalo R; Altshuler, David; Auton, Adam; Brooks, Lisa D; Durbin, Richard M; Gibbs, Richard A; Hurles, Matt E; McVean, Gil A

2010-10-28

The 1000 Genomes Project aims to provide a deep characterization of human genome sequence variation as a foundation for investigating the relationship between genotype and phenotype. Here we present results of the pilot phase of the project, designed to develop and compare different strategies for genome-wide sequencing with high-throughput platforms. We undertook three projects: low-coverage whole-genome sequencing of 179 individuals from four populations; high-coverage sequencing of two mother-father-child trios; and exon-targeted sequencing of 697 individuals from seven populations. We describe the location, allele frequency and local haplotype structure of approximately 15 million single nucleotide polymorphisms, 1 million short insertions and deletions, and 20,000 structural variants, most of which were previously undescribed. We show that, because we have catalogued the vast majority of common variation, over 95% of the currently accessible variants found in any individual are present in this data set. On average, each person is found to carry approximately 250 to 300 loss-of-function variants in annotated genes and 50 to 100 variants previously implicated in inherited disorders. We demonstrate how these results can be used to inform association and functional studies. From the two trios, we directly estimate the rate of de novo germline base substitution mutations to be approximately 10(-8) per base pair per generation. We explore the data with regard to signatures of natural selection, and identify a marked reduction of genetic variation in the neighbourhood of genes, due to selection at linked sites. These methods and public data will support the next phase of human genetic research.

Optimized O'Neill/Glaser Model for Human Population of Space and its Impact on Survival Probabilities

Science.gov (United States)

Curreri, Peter A.

2010-01-01

Two contemporary issues foretell a shift from our historical Earth based industrial economy and habitation to a solar system based society. The first is the limits to Earth s carrying capacity, that is the maximum number of people that the Earth can support before a catastrophic impact to the health of the planet and human species occurs. The simple example of carrying capacity is that of a bacterial colony in a Petri dish with a limited amount of nutrient. The colony experiences exponential population growth until the carrying capacity is reached after which catastrophic depopulation often results. Estimates of the Earth s carrying capacity vary between 14 and 40 billion people. Although at current population growth rates we may have over a century before we reach Earth s carrying limit our influence on climate and resources on the planetary scale is becoming scientifically established. The second issue is the exponential growth of knowledge and technological power. The exponential growth of technology interacts with the exponential growth of population in a manner that is unique to a highly intelligent species. Thus, the predicted consequences (world famines etc.) of the limits to growth have been largely avoided due to technological advances. However, at the mid twentieth century a critical coincidence occurred in these two trends humanity obtained the technological ability to extinguish life on the planetary scale (by nuclear, chemical, biological means) and attained the ability to expand human life beyond Earth. This paper examines an optimized O'Neill/Glaser model (O Neill 1975; Curreri 2007; Detweiler and Curreri 2008) for the economic human population of space. Critical to this model is the utilization of extraterrestrial resources, solar power and spaced based labor. A simple statistical analysis is then performed which predicts the robustness of a single planet based technological society versus that of multiple world (independent habitats) society.

Heterogeneity within populations of recombinant Chinese hamster ovary cells expressing human interferon-gamma.

Science.gov (United States)

Coppen, S R; Newsam, R; Bull, A T; Baines, A J

1995-04-20

The Chinese hamster ovary (CHO) cell line has great commercial importance in the production of recombinant human proteins, especially those for therapeutic use. Much attention has been paid to CHO cell population physiology in order to define factors affecting product fidelity and yield. Such studies have revealed that recombinant proteins, including human interferon-gamma (IFN-gamma), can be heterogeneous both in glycosylation and in proteolytic processing. The type of heterogeneity observed depends on the growth physiology of the cell population, although the relationship between them is complex. In this article we report results of a cytological study of the CHO320 line which expresses recombinant human IFN-gamma. When grown in suspension culture, this cell line exhibited three types of heterogeneity: (1) heterogeneity of the production of IFN-gamma within the cell population, (2) heterogeneity of the number of nuclei and mitotic spindles in dividing cells, and (3) heterogeneity of cellular environment. The last of these arises from cell aggregates which form in suspension culture: Some cells are exposed to the culture medium; others are fully enclosed within the mass with little or no direct access to the medium. Thus, live cells producing IFN-gamma are heterogeneous in their environment, with variable access to O(2) and nutrients. Within the aggregates, it appears that live cells proliferate on a dead cell mass. The layer of live cells can be several cells deep. Specific cell-cell attachments are observed between the living cells in these aggregates. Two proteins, known to be required for the formation of certain types of intercellular junctions, spectrin and vinculin, have been localized to the regions of cell-cell contact. The aggregation of the cells appears to be an active process requiring protein synthesis. (c) 1995 John Wiley & Sons, Inc.

A physician's reflection on the moral use of human papilloma virus vaccine.

Science.gov (United States)

Burke, Greg F

2016-08-01

Controversies often surround the use of vaccines, particularly among the pediatric population. Often, the possible temporal relationship between vaccination and subsequent disease is at the center of the controversy. However, others have questioned the moral status of the human papilloma virus (HPV) vaccine because of some instances of state coercion and also the possibility that the vaccine may promote promiscuity. This article addresses the moral status of the HPV vaccine from the perspective of a primary care physician and father of four daughters. Lay Summary: Parents are often asked by pediatricians for permission to vaccinate their children under the age of consent against the sexually transmitted virus HPV. This article addresses the medical and moral concerns about vaccination with some guiding principles to assist in a final decision.

Threatened species richness along a Himalayan elevational gradient: quantifying the influences of human population density, range size, and geometric constraints.

Science.gov (United States)

Paudel, Prakash Kumar; Sipos, Jan; Brodie, Jedediah F

2018-02-07

A crucial step in conserving biodiversity is to identify the distributions of threatened species and the factors associated with species threat status. In the biodiversity hotspot of the Himalaya, very little is known about which locations harbour the highest diversity of threatened species and whether diversity of such species is related to area, mid-domain effects (MDE), range size, or human density. In this study, we assessed the drivers of variation in richness of threatened birds, mammals, reptiles, actinopterygii, and amphibians along an elevational gradient in Nepal Himalaya. Although geometric constraints (MDE), species range size, and human population density were significantly related to threatened species richness, the interaction between range size and human population density was of greater importance. Threatened species richness was positively associated with human population density and negatively associated with range size. In areas with high richness of threatened species, species ranges tend to be small. The preponderance of species at risk of extinction at low elevations in the subtropical biodiversity hotspot could be due to the double impact of smaller range sizes and higher human density.

Connectivity of tiger (Panthera tigris) populations in the human-influenced forest mosaic of Central India.

Science.gov (United States)

Joshi, Aditya; Vaidyanathan, Srinivas; Mondol, Samrat; Edgaonkar, Advait; Ramakrishnan, Uma

2013-01-01

Today, most wild tigers live in small, isolated Protected Areas within human dominated landscapes in the Indian subcontinent. Future survival of tigers depends on increasing local population size, as well as maintaining connectivity between populations. While significant conservation effort has been invested in increasing tiger population size, few initiatives have focused on landscape-level connectivity and on understanding the effect different landscape elements have on maintaining connectivity. We combined individual-based genetic and landscape ecology approaches to address this issue in six protected areas with varying tiger densities and separation in the Central Indian tiger landscape. We non-invasively sampled 55 tigers from different protected areas within this landscape. Maximum-likelihood and Bayesian genetic assignment tests indicate long-range tiger dispersal (on the order of 650 km) between protected areas. Further geo-spatial analyses revealed that tiger connectivity was affected by landscape elements such as human settlements, road density and host-population tiger density, but not by distance between populations. Our results elucidate the importance of landscape and habitat viability outside and between protected areas and provide a quantitative approach to test functionality of tiger corridors. We suggest future management strategies aim to minimize urban expansion between protected areas to maximize tiger connectivity. Achieving this goal in the context of ongoing urbanization and need to sustain current economic growth exerts enormous pressure on the remaining tiger habitats and emerges as a big challenge to conserve wild tigers in the Indian subcontinent.

Connectivity of tiger (Panthera tigris populations in the human-influenced forest mosaic of Central India.

Directory of Open Access Journals (Sweden)

Aditya Joshi

Full Text Available Today, most wild tigers live in small, isolated Protected Areas within human dominated landscapes in the Indian subcontinent. Future survival of tigers depends on increasing local population size, as well as maintaining connectivity between populations. While significant conservation effort has been invested in increasing tiger population size, few initiatives have focused on landscape-level connectivity and on understanding the effect different landscape elements have on maintaining connectivity. We combined individual-based genetic and landscape ecology approaches to address this issue in six protected areas with varying tiger densities and separation in the Central Indian tiger landscape. We non-invasively sampled 55 tigers from different protected areas within this landscape. Maximum-likelihood and Bayesian genetic assignment tests indicate long-range tiger dispersal (on the order of 650 km between protected areas. Further geo-spatial analyses revealed that tiger connectivity was affected by landscape elements such as human settlements, road density and host-population tiger density, but not by distance between populations. Our results elucidate the importance of landscape and habitat viability outside and between protected areas and provide a quantitative approach to test functionality of tiger corridors. We suggest future management strategies aim to minimize urban expansion between protected areas to maximize tiger connectivity. Achieving this goal in the context of ongoing urbanization and need to sustain current economic growth exerts enormous pressure on the remaining tiger habitats and emerges as a big challenge to conserve wild tigers in the Indian subcontinent.

Radiation protection for human population

International Nuclear Information System (INIS)

Bogdevich, I.M.; Kenigsberg, Ya.Eh.; Minenko, V.F.; Mrochek, A.G.; Rolevich, I.V.; Skurat, V.V.; Sharovarov, G.A.

1998-01-01

The purpose of researches is development of methods and means of reduction of radiation risk caused by the Chernobyl accident consequences by means of decrease of both individual and collective dozes by realization of special protective measures. The reconstruction of average collective accumulated irradiation dozes of the inhabitants of the contaminated populated localities of Belarus is carried out; the forecast of development of radiation induced oncologic diseases is given. The laws of formation of annual irradiation dozes are investigated; the prevailing role of internal irradiation dozes in formation of total dose loadings is detected. On this basis a number of practical projects directed on creation of effective land tenure and decrease of radioactive contamination of agricultural production, as well as decontamination technologies and radioactive waste management are executed. Are given the results of researches carried out in Belarus in 1997 on the following directions: dose monitoring of the population, estimation and forecast of both collective irradiation dozes and risks of radiation induced diseases; development and optimization of a complex of measures for effective land use and decrease of radioactive contamination of agricultural production in order to reduce irradiation dozes of the population; development of complex technologies and means of decontamination, treatment and burial of radioactive wastes; development and ground of the measures for increase of radiation protection of the population of Belarus during of the reducing period after the Chernobyl accident; development of complex system of an estimation and decision-making on problems of radiation protection of the population living on contaminated territories

Cross-population myelination covariance of human cerebral cortex.

Science.gov (United States)

Ma, Zhiwei; Zhang, Nanyin

2017-09-01

Cross-population covariance of brain morphometric quantities provides a measure of interareal connectivity, as it is believed to be determined by the coordinated neurodevelopment of connected brain regions. Although useful, structural covariance analysis predominantly employed bulky morphological measures with mixed compartments, whereas studies of the structural covariance of any specific subdivisions such as myelin are rare. Characterizing myelination covariance is of interest, as it will reveal connectivity patterns determined by coordinated development of myeloarchitecture between brain regions. Using myelin content MRI maps from the Human Connectome Project, here we showed that the cortical myelination covariance was highly reproducible, and exhibited a brain organization similar to that previously revealed by other connectivity measures. Additionally, the myelination covariance network shared common topological features of human brain networks such as small-worldness. Furthermore, we found that the correlation between myelination covariance and resting-state functional connectivity (RSFC) was uniform within each resting-state network (RSN), but could considerably vary across RSNs. Interestingly, this myelination covariance-RSFC correlation was appreciably stronger in sensory and motor networks than cognitive and polymodal association networks, possibly due to their different circuitry structures. This study has established a new brain connectivity measure specifically related to axons, and this measure can be valuable to investigating coordinated myeloarchitecture development. Hum Brain Mapp 38:4730-4743, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

When gender matters: new insights into the relationships between social systems and the genetic structure of human populations.

Science.gov (United States)

Destro Bisol, Giovanni; Capocasa, Marco; Anagnostou, Paolo

2012-10-01

Due to its important effects on the ecological dynamics and the genetic structure of species, biologists have long been interested in gender-biased dispersal, a condition where one gender is more prone to move from the natal site. More recently, this topic has attracted a great attention from human evolutionary geneticists. Considering the close relations between residential rules and social structure, gender-biased dispersal is, in fact, regarded as an important case study concerning the effects of socio-cultural factors on human genetic variation. It all started with the seminal paper by Mark Seielstad, Erich Minch and Luigi Luca Cavalli Sforza from Stanford University (Seielstad et al. 1998). They observed a larger differentiation for Y-chromosome than mitochondrial DNA between extant human populations, purportedly a consequence of the prevalence of long-term patrilocality in human societies. Subsequent studies, however, have highlighted the need to consider geographically close and culturally homogeneous groups, disentangle signals due to different peopling events and obtain unbiased estimates of genetic diversity. In this issue of Molecular Ecology, not only do Marks et al. (2012) adopt an experimental design which addresses these concerns, but they also take a further and important step forward by integrating the genetic analysis of two distant populations, the Basotho and Spanish, with data regarding migration rates and matrimonial distances. Using both empirical evidence and simulations, the authors show that female-biased migration due to patrilocality might shape the genetic structure of human populations only at short ranges and under substantial differences in migration rates between genders. Providing a quantitative framework for future studies of the effects of residential rules on the human genome, this study paves the way for further developments in the field. On a wider perspective, Marks et al.'s work demonstrates the power of approaches which

Genetic variation in natural honeybee populations, Apis mellifera capensis

Science.gov (United States)

Hepburn, Randall; Neumann, Peter; Radloff, Sarah E.

2004-09-01

Genetic variation in honeybee, Apis mellifera, populations can be considerably influenced by breeding and commercial introductions, especially in areas with abundant beekeeping. However, in southern Africa apiculture is based on the capture of wild swarms, and queen rearing is virtually absent. Moreover, the introduction of European subspecies constantly failed in the Cape region. We therefore hypothesize a low human impact on genetic variation in populations of Cape honeybees, Apis mellifera capensis. A novel solution to studying genetic variation in honeybee populations based on thelytokous worker reproduction is applied to test this hypothesis. Environmental effects on metrical morphological characters of the phenotype are separated to obtain a genetic residual component. The genetic residuals are then re-calculated as coefficients of genetic variation. Characters measured included hair length on the abdomen, width and length of wax plate, and three wing angles. The data show for the first time that genetic variation in Cape honeybee populations is independent of beekeeping density and probably reflects naturally occurring processes such as gene flow due to topographic and climatic variation on a microscale.

The local lymph node assay compared with the human maximization test as an indicator of allergic potency in humans using patch test clinic populations.

Science.gov (United States)

Zaghi, Danny; Maibach, Howard I

2009-01-01

The human maximization test (HMT) is a method to evaluate potency in humans, while the local lymph node assay (LLNA) is a test method that allows for the measuring of the allergic potency of a substance in a rodent. It has been proposed that an EC3 value (the value obtained by the LLNA test, ie, the concentration of an allergen leading to a 3-fold increase of baseline proliferation rate) would be a reliable indicator for a compound's allergic potency in humans. This paper compares the correlation between the EC3 value of a compound and its allergic occurrence in the general population with the correlation between the HMT of the compound and its allergic occurrence in the general population, to determine the relationship to potency. The correlation values when outliers were removed from the sample were -0.56 and -0.71 for LLNA and HMT, respectively, suggesting that there is a possible 20% error margin in LLNA's ability to predict potency. The data also suggest that other factors (such as exposure) could play up to a 30% role in the determination of allergic occurrence in the general population. The potency assays might be made more clinically relevant for predicting allergic frequencies by including a frequency factor and other factors in its dermatotoxicological interpretation.

Influence of human population movements on urban climate of Beijing during the Chinese New Year holiday

Science.gov (United States)

Zhang, Jingyong; Wu, Lingyun

2017-03-01

The population movements for the Chinese New Year (CNY) celebrations, known as the world’s largest yearly migration of human beings, have grown rapidly in the past several decades. The massive population outflows from urban areas largely reduce anthropogenic heat release and modify some other processes, and may thus have noticeable impacts on urban climate of large cities in China. Here, we use Beijing as an example to present observational evidence for such impacts over the period of 1990-2014. Our results show a significant cooling trend of up to 0.55 °C per decade, particularly at the nighttime during the CNY holiday relative to the background period. The average nighttime cooling effect during 2005-2014 reaches 0.94 °C relative to the 1990s, significant at the 99% confidence level. The further analysis supports that the cooling during the CNY holiday is attributable primarily to the population outflow of Beijing. These findings illustrate the importance of population movements in influencing urban climate despite certain limitations. As the world is becoming more mobile and increasingly urban, more efforts are called for to understand the role of human mobility at various spatial and temporal scales.

Survey of U.S. zoo and aquarium animal care staff attitudes regarding humane euthanasia for population management.

Science.gov (United States)

Powell, David M; Ardaiolo, Matthew

2016-05-01

The humane euthanasia of animals for population management, or culling, has been suggested as one possible tool for managing animal populations for sustainability, and recent, highly publicized euthanasia of zoo animals in Copenhagen has stimulated global conversation about population management in zoos. We conducted a nationwide survey of U.S. zoo and aquarium personnel, including keepers, managers, and leaders of AZA animal programs, to assess their overall attitudes regarding population management euthanasia. The surveyed populations were generally very aware of the concept of population management euthanasia. Managers and animal program leaders were more supportive of euthanasia than keepers. We found that regardless of role, men were more supportive of euthanasia than women. Those personnel who were aware of instances of population management euthanasia at their institutions before were more supportive of it than those who were not. Support for culling varied with the kind of animal being considered for it, with three general taxon acceptability groupings emerging. Education, tenure in the profession, taxonomic expertise, and whether or not the responder took the survey before or after the Copenhagen events were not strong predictors of attitudes. Overall, the surveyed populations were approximately evenly split in terms of being in favor of euthanasia, not supporting euthanasia, or being unsure. Most responders indicated that they would be more likely to accept culling if more information was provided on its rationale. These results will form the basis for further discussions on the role of humane euthanasia for population management. Zoo Biol. 35:187-200, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Human Rights Education in Israel: Four Types of Good Citizenship

Directory of Open Access Journals (Sweden)

Ayman Kamel Agbaria

2016-06-01

Full Text Available This article examines the involvement of civil society organizations in human rights education (HRE in Israel. Focussing on the educational programs of the Association for Civil Rights in Israel (ACRI, as a qualitative instrumental case study, this article examines the conceptions of good citizenship embedded in these programs. Specifically, the article analyzes the educational programs’ goals, content, targeted populations, and practices. The analysis revealed that ACRI’s HRE model reflect four ideal types of citizens: citizen of a democratic liberal state, citizen of a participatory polity, citizen of an ethical profession, and citizen of an empowered community. These constitute a multilayered human rights discourse that enables ACRI to engage differentially with various sectors and populations, while still remaining faithful to the ethno-national parameters of a Jewish and democratic state political framework.

Assessment of environmental exposure to mercury in selected human populations as studied by nuclear and other techniques

International Nuclear Information System (INIS)

1995-01-01

A Co-ordinated Research Programme (CRP) on assessment of environmental exposure to mercury in selected human populations as studied by nuclear and other techniques was initiated by the IAEA in 1990. The purpose of this CRP is to promote national and regional studies to evaluate the exposure of selected population groups to mercury and methylmercury and to estimate potential risks in these groups. The programme is focused on the analysis of human head hair for the determination of mercury and methylmercury. The CRP has two main components: (i) identifying population groups that are at risk, and (ii) studying health effects in the exposed persons, particularly pregnant women and the babies born to them. This document reports the discussions held during the third Research Co-ordination Meeting (RCM) for the CRP which took place at the IAEA, Monaco Laboratory. (author)

Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

International Nuclear Information System (INIS)

Fabrikant, J.I.

1981-05-01

The current knowledge of the carcinogenic effect of radiation in man is considered. The discussion is restricted to dose-incidence data in humans, particularly to certain of those epidemiological studies of human populations that are used most frequently for risk estimation for low-dose radiation carcinogenesis in man. Emphasis is placed solely on those surveys concerned with nuclear explosions and medical exposures

Food and fitness: associations between crop yields and life-history traits in a longitudinally monitored pre-industrial human population.

Science.gov (United States)

Hayward, Adam D; Holopainen, Jari; Pettay, Jenni E; Lummaa, Virpi

2012-10-22

Severe food shortage is associated with increased mortality and reduced reproductive success in contemporary and historical human populations. Studies of wild animal populations have shown that subtle variation in environmental conditions can influence patterns of mortality, fecundity and natural selection, but the fitness implications of such subtle variation on human populations are unclear. Here, we use longitudinal data on local grain production, births, marriages and mortality so as to assess the impact of crop yield variation on individual age-specific mortality and fecundity in two pre-industrial Finnish populations. Although crop yields and fitness traits showed profound year-to-year variation across the 70-year study period, associations between crop yields and mortality or fecundity were generally weak. However, post-reproductive individuals of both sexes, and individuals of lower socio-economic status experienced higher mortality when crop yields were low. This is the first longitudinal, individual-based study of the associations between environmental variation and fitness traits in pre-industrial humans, which emphasizes the importance of a portfolio of mechanisms for coping with low food availability in such populations. The results are consistent with evolutionary ecological predictions that natural selection for resilience to food shortage is likely to weaken with age and be most severe on those with the fewest resources.

Chapter 6. Modeling human impacts to the Borderlands environment from a fire ecology perspective

Science.gov (United States)

Suzanne K. Fish

2006-01-01

Theoretical and topical orientations in current archaeology address the interaction between past human populations and their environment. These themes reflect ecological frameworks that were incorporated into the social sciences by the 1950s, as exemplified by the influential publication, Man?s Role in Changing the Face of the Earth (Thomas 1956). Cultural practices...

An imbalance in progenitor cell populations reflects tumour progression in breast cancer primary culture models

LENUS (Irish Health Repository)

Donatello, Simona

2011-04-26

Abstract Background Many factors influence breast cancer progression, including the ability of progenitor cells to sustain or increase net tumour cell numbers. Our aim was to define whether alterations in putative progenitor populations could predict clinicopathological factors of prognostic importance for cancer progression. Methods Primary cultures were established from human breast tumour and adjacent non-tumour tissue. Putative progenitor cell populations were isolated based on co-expression or concomitant absence of the epithelial and myoepithelial markers EPCAM and CALLA respectively. Results Significant reductions in cellular senescence were observed in tumour versus non-tumour cultures, accompanied by a stepwise increase in proliferation:senescence ratios. A novel correlation between tumour aggressiveness and an imbalance of putative progenitor subpopulations was also observed. Specifically, an increased double-negative (DN) to double-positive (DP) ratio distinguished aggressive tumours of high grade, estrogen receptor-negativity or HER2-positivity. The DN:DP ratio was also higher in malignant MDA-MB-231 cells relative to non-tumourogenic MCF-10A cells. Ultrastructural analysis of the DN subpopulation in an invasive tumour culture revealed enrichment in lipofuscin bodies, markers of ageing or senescent cells. Conclusions Our results suggest that an imbalance in tumour progenitor subpopulations imbalances the functional relationship between proliferation and senescence, creating a microenvironment favouring tumour progression.

Development of a 6 DOF force-reflecting master input device

International Nuclear Information System (INIS)

Yoon, Ji Sup; Yoon, Ho Sik

1999-05-01

The teleoperator is a very effective tool for various tasks of nuclear application in that it can reduce the operators' exposure to the radiation. For the utmost performances of the teleoperator, the force reflection capability is essential. This capability represents a function of transmitting the contact force of teleoperator with the object to the human operator. With this function the human operator in the remote area can effectively guide the motion of the teleoperator so that it can follow a safety guaranteed path. In this research a fully force reflectible input device 96 axis) is developed. To develop the force reflecting device, the state of art is surveyed. Based on this survey, the 6 DOF manipulator which controls a power manipulator is fabricated and its performance is investigated. Also, various force reflection algorithms analyzed and the enhanced algorithm is proposed. (author). 18 refs., 4 tabs., 26 figs

Development of a 6 DOF force-reflecting master input device

Energy Technology Data Exchange (ETDEWEB)

Yoon, Ji Sup; Yoon, Ho Sik

1999-05-01

The teleoperator is a very effective tool for various tasks of nuclear application in that it can reduce the operators' exposure to the radiation. For the utmost performances of the teleoperator, the force reflection capability is essential. This capability represents a function of transmitting the contact force of teleoperator with the object to the human operator. With this function the human operator in the remote area can effectively guide the motion of the teleoperator so that it can follow a safety guaranteed path. In this research a fully force reflectible input device 96 axis is developed. To develop the force reflecting device, the state of art is surveyed. Based on this survey, the 6 DOF manipulator which controls a power manipulator is fabricated and its performance is investigated. Also, various force reflection algorithms analyzed and the enhanced algorithm is proposed. (author). 18 refs., 4 tabs., 26 fi0008.

Development of a 6 DOF force-reflecting master input device

Energy Technology Data Exchange (ETDEWEB)

Yoon, Ji Sup; Yoon, Ho Sik

1999-05-01

The teleoperator is a very effective tool for various tasks of nuclear application in that it can reduce the operators' exposure to the radiation. For the utmost performances of the teleoperator, the force reflection capability is essential. This capability represents a function of transmitting the contact force of teleoperator with the object to the human operator. With this function the human operator in the remote area can effectively guide the motion of the teleoperator so that it can follow a safety guaranteed path. In this research a fully force reflectible input device 96 axis is developed. To develop the force reflecting device, the state of art is surveyed. Based on this survey, the 6 DOF manipulator which controls a power manipulator is fabricated and its performance is investigated. Also, various force reflection algorithms analyzed and the enhanced algorithm is proposed. (author). 18 refs., 4 tabs., 26 fi0008.

Functional responses of human hunters to their prey - why harvest statistics may not always reflect changes in prey population abundance

DEFF Research Database (Denmark)

Kahlert, Johnny Abildgaard; Fox, Anthony David; Heldbjerg, Henning

pigeon Columba palumbus, coot Fulica atra, grey partridge Perdix perdix, roe deer Capreolus capreolus and brown hare Lepus europaeus in Denmark. If we consider hunting a form of predator-prey interaction, the annual kill can be viewed as a predator functional response to prey population size. Convergence...

The Art of Self-Reflection

Science.gov (United States)

Villano, Matt

2006-01-01

Metaphysically speaking, the idea of self-reflection has been the subject of discussion for thousands of years. The idea carried human beings through the Renaissance, and an entire movement tied to it sparked a sociopolitical movement called the Enlightenment. In more recent times, thought leaders such as Immanuel Kant, Karl Marx, and Sigmund…

Stabilizing impacts in force-reflecting teleoperation using distance-to-impact estimates

International Nuclear Information System (INIS)

McAree, P.R.; Daniel, R.W.

2000-01-01

The level of force that can be stably reflected to the human operator in a force-reflecting teleoperator is constrained by the dynamics of impact between the slave arm and its environment. This paper models the underlying dynamics of impact and describes how the impact effects can be minimized using estimates of the distance between the slave and objects in its workspace. The approach is based on stochastic variational principles and seeks to limit the momentum of the slave arm at impact. Preliminary experimental results show that the approach allows extension of the range of frequencies that can be stably reflected to the human operator

Organizing of medical ensurance of human population under extreme conditions. Summaries of reports of scientific-practical conference

International Nuclear Information System (INIS)

1994-01-01

Summary of reports are presented of Scientific-Practical conference on the organizing of medical ensurance of human population under extreme conditions including radiation accidents. The conference held in Moscow in October, 1994. It covered problems of organizing medical ensurance of population, medical surveillance problems, sanitary-hygienic and epidemiological problems (including radiation protection), and medical provision problems under extreme conditions

The Social and Local Construction of Human Rights. Reflections from the Perspective of the Right to Education in Mexico

Directory of Open Access Journals (Sweden)

Víctor Alfonzo Zertuche Cobos

2018-05-01

Full Text Available The present article constitutes a critical reflection on human rights from the social-legal field in Mexico. Its purpose is to provide a discussion on a current legal and institutional reality, that is, the right to education in human rights based on one of the most important constitutional reforms in recent years in the field of human rights: the reform of June 2011. This reform, by the article 1° and 3° of the Constitution, introduced a public policy (proposed to the National Development Plan 2013-2018, along with the National Human Rights Program 2014-2018 within the federal public administration whose object is to implement the teaching of human rights at the national level. In this proposal, we observe two effects, one positive and one negative, inscribed only in the institutional or official dimension of the Mexican State, from which is derived a third positive effect for the social or local sphere, that is to say, for the space where the popular sectors or cultural minorities live. Therefore, it is in this social or local sphere where the third positive effect of the national public policy would take place to rethink the counter-hegemonic and alternative use of the right to education in human rights, from where would be possible the social-local construction or reconstruction of human rights that the present and future society requires with some urgency.

Levels of perfluorooctanesulfonate and related fluorochemicals in human blood from the general population of Korea

Energy Technology Data Exchange (ETDEWEB)

Yang, Jae-Ho; Kim, Sun-Young; Shin, Im-Hee [Catholic Univ. of Daegu, School of Medicine, Dept. of Pharmacology/Toxicology, Daegu (Korea); Kannan, K. [Wardsworth Center, New York State Dept. of Health and Dept. of Env. Health and Tox., SUNY, Albany, NY (United States)

2004-09-15

Perfluorooctanesulfonate (PFOS) was found to be widespread in human populations and wildlife Major applications of these POSF-based products have included surfactants in: specialty paper and packaging products, carpet, upholstery, and textile products and in certain insecticide formulation. Depending on the specific functional derivatization or the degree of polymerization, such POSF based products may degrade or metabolize to PFOS, a stable and persistent end product that has the potential to bioaccumulate in the food chain. The mechanisms and pathways leading to the presence of PFOS in human blood are not well characterized but likely involve environmental and dietary exposure to PFOS or to precursor molecules of PFOS. PFOS and related perfluorinated compounds have recently been detected at low parts per billion (nanogram per milliliter) concentrations in the general population from 10 different countries including Korea. In the present report, the levels of perfluoroalkylated compounds in the general population from Korea were analyzed with respect to occupation, smoking status, sex, age and socio-economic status. The degree of association between the four target fluorochemicals measured in this study (PFOS, PFHxS, PFOA, and PFOSA) were also analyzed by linear regression to determine the potential association between their sources of exposure.

Genetic diversity and population structure in Polygonum cespitosum: insights to an ongoing plant invasion.

Directory of Open Access Journals (Sweden)

Silvia Matesanz

Full Text Available Molecular markers can help elucidate how neutral evolutionary forces and introduction history contribute to genetic variation in invaders. We examined genetic diversity, population structure and colonization patterns in the invasive Polygonum cespitosum, a highly selfing, tetraploid Asian annual introduced to North America. We used nine diploidized polymorphic microsatellite markers to study 16 populations in the introduced range (northeastern North America, via the analyses of 516 individuals, and asked the following questions: 1 Do populations have differing levels of within-population genetic diversity? 2 Do populations form distinct genetic clusters? 3 Does population structure reflect either geographic distances or habitat similarities? We found low heterozygosity in all populations, consistent with the selfing mating system of P. cespitosum. Despite the high selfing levels, we found substantial genetic variation within and among P. cespitosum populations, based on the percentage of polymorphic loci, allelic richness, and expected heterozygosity. Inferences from individual assignment tests (Bayesian clustering and pairwise FST values indicated high among-population differentiation, which indicates that the effects of gene flow are limited relative to those of genetic drift, probably due to the high selfing rates and the limited seed dispersal ability of P. cespitosum. Population structure did not reflect a pattern of isolation by distance nor was it related to habitat similarities. Rather, population structure appears to be the result of the random movement of propagules across the introduced range, possibly associated with human dispersal. Furthermore, the high population differentiation, genetic diversity, and fine-scale genetic structure (populations founded by individuals from different genetic sources in the introduced range suggest that multiple introductions to this region may have occurred. High genetic diversity may further

Beyond Borders (2003, or the human side of medicine

Directory of Open Access Journals (Sweden)

Patricia Maria Rabelo Annes

2008-10-01

Full Text Available Beyond Borders (2003 reflects on the human side of people and the wish to help those most in need, special emphasis being placed on the medical profession. It also reflects the main outcomes of armed conflicts on the health of the populations affected by the strife and the difficulties encountered by those interested in helping out. The frequent denouncements (such as that made in the film have not changed the penury of refugees and internally displaced persons, who remain with no definitive solution to their problems, despite the efforts of many, such that it is crucial to attack the root causes themselves instead of trying to minimise the horrific consequences generated by armed conflicts.

Variation in population exposure in China as a result of differing human activities

Energy Technology Data Exchange (ETDEWEB)

Pan, Z.Q. [China Atomic Energy Authority, Beijing (China). Bureau of Safety, Protection and Health; Guo, M.Q. [China Nuclear Industry Huaqing Company, Beijing (China)

1995-08-01

The necessity of studying the variations in radiation levels dispassionately is discussed. Human activities may increase, but can also decrease, radiation dose to the population. Travel by air may cause a rise in population collective dose by 3.6 x 10 man.Sv, and travel by ship, train and vehicle may lead to a drop of 5.36 x 10{sup 2} man.Sv. Dwellings of coal cinder brick may increase collective dose by 3.5 x 10{sup 3} man.Sv, and buildings of reinforced concrete may decrease collective dose by 3.7 x 10{sup 3} man.Sv. It is inadequate to study only those activities which may increase radiation levels. (author).

Human and cattle population changes in deltaic West Bengal, India between 1977-1987

Energy Technology Data Exchange (ETDEWEB)

Odend' hal, S.

1988-03-01

In 1967-1970, 3.81 km/sup 2/ of a densely populated deltaic area of Hooghly district in West Bengal, India was intensively studied. This same area was resurveyed in 1977 and 1987. From 1977-1987, the human population has increased 10.1%, while the number of households has increased 25%. The total number of children below 10 years of age has diminished. The cattle have increased 26.5%. The number of working-age male cattle has dropped significantly with reliance, primarily on hand tractor power for field cultivation. The number of female cattle has increased substantially. Artificial insemination and the use of temperate breeds of bulls have had an obvious impact. Improvements in the general environment were observed.

Trends in the use and cost of human and analogue insulins in a Colombian population, 2011-2015.

Science.gov (United States)

Torres, D R; Portilla, A; Machado-Duque, M E; Machado-Alba, J E

2017-12-01

Diabetes mellitus is a common disease among the general population and imposes considerable costs on health care systems. Insulin is used to treat type 1 diabetes mellitus and as an adjuvant to oral agents in advanced stages of type 2 diabetes mellitus. The objective was to describe the trends in use and cost of human and analogue insulins for Colombian patients. Descriptive retrospective analysis of prescriptions of human and analogue insulins on a monthly basis for the period from July 1, 2011 to February 2, 2015. Information was collected for the database population of two insurance companies. Frequencies and proportions were calculated; estimated economic impact was expressed as net cost and cost per thousand inhabitants per day. During the observation period, there was continuous growth in use of insulin, mainly in analogue forms (34.0% growth). At the start of the study, 10.4% of subjects were using an analogue insulin; this figure was 62.6% at the end of the study. In 2012, the average cost per 1000 inhabitants/day was US$1.7 for analogue and US$0.8 for human insulins. At the end of the observation period these costs had risen to US$9.2 for analogue (441.1% increase) and fallen to US$0.5 for human insulin (58.3% decrease). There has been an increase in the unit cost and frequency of use of insulin analogues for anti-diabetic therapy in Colombian patients. Moreover, there is controversy over whether insulin analogues are a more cost-effective treatment than human insulins for the general diabetic population. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Preconception healthcare delivery at a population level: construction of public health models of preconception care.

Science.gov (United States)

Shannon, Geordan D; Alberg, Corinna; Nacul, Luis; Pashayan, Nora

2014-08-01

A key challenge of preconception healthcare is identifying how it can best be delivered at a population level. To review current strategies of preconception healthcare, explore methods of preconception healthcare delivery, and develop public health models which reflect different preconception healthcare pathways. Preconception care strategies, programmes and evaluations were identified through a review of Medline and Embase databases. Search terms included: preconception, pre-pregnancy, intervention, primary care, healthcare, model, delivery, program, prevention, trial, effectiveness, congenital disorders OR abnormalities, evaluation, assessment, impact. Inclusion criteria for review articles were: (1) English, (2) human subjects, (3) women of childbearing age, (4) 1980–current data, (5) all countries, (6) both high risk and universal approaches, (7) guidelines or recommendations, (8) opinion articles, (9) experimental studies. Exclusion criteria were: (1) non-human subjects, (2) non-English, (3) outside of the specified timeframe, (4) articles on male healthcare. The results of the literature review were synthesised into public health models of care: (1) primary care; (2) hospital-based and inter-conception care; (3) specific preconception care clinics; and, (4) community outreach. Fifteen evaluations of preconception care were identified. Community programmes demonstrated a significant impact on substance use, folic acid supplementation, diabetes optimization, and hyperphenylalaninemia. An ideal preconception visits entail risk screening, education, and intervention if indicated. Subsequently, four public health models were developed synthesizing preconception care delivery at a population level. Heterogeneity of risk factors, health systems and strategies of care reflect the lack of consensus about the best way to deliver preconception care. The proposed models aim to reflect differing aspects of preconception healthcare delivery.

Population Physiologically-Based Pharmacokinetic Modeling for the Human Lactational Transfer of PCB 153 with Consideration of Worldwide Human Biomonitoring Results

Energy Technology Data Exchange (ETDEWEB)

Redding, Laurel E.; Sohn, Michael D.; McKone, Thomas E.; Wang, Shu-Li; Hsieh, Dennis P. H.; Yang, Raymond S. H.

2008-03-01

We developed a physiologically based pharmacokinetic model of PCB 153 in women, and predict its transfer via lactation to infants. The model is the first human, population-scale lactational model for PCB 153. Data in the literature provided estimates for model development and for performance assessment. Physiological parameters were taken from a cohort in Taiwan and from reference values in the literature. We estimated partition coefficients based on chemical structure and the lipid content in various body tissues. Using exposure data in Japan, we predicted acquired body burden of PCB 153 at an average childbearing age of 25 years and compare predictions to measurements from studies in multiple countries. Forward-model predictions agree well with human biomonitoring measurements, as represented by summary statistics and uncertainty estimates. The model successfully describes the range of possible PCB 153 dispositions in maternal milk, suggesting a promising option for back estimating doses for various populations. One example of reverse dosimetry modeling was attempted using our PBPK model for possible exposure scenarios in Canadian Inuits who had the highest level of PCB 153 in their milk in the world.

[Excessive population and health].

Science.gov (United States)

Rivera, A A

1995-07-01

Population density in El Salvador is among the highest in the world. In metropolitan San Salvador and the other main cities, crowding, squatter settlements, unemployment and underemployment, scarcity of basic services, squalor, and other social pathologies appear to be increasing. Overpopulation poses an enormous challenge for development. Reflection on the benefits of family planning has been delayed in El Salvador, and in the interim there have been increases in social inequality, misery, and hunger. Family planning programs have been referred to as "neo-Malthusian" and contrary to the right to life, but in fact they promote birth spacing and free selection of methods by couples, contributing to improvement in the quality of family life. Family planning allows couples to limit their offspring to those they can adequately care for emotionally and materially. People must be shown that family planning alleviates many of humanity's problems.

Genome-wide diversity and differentiation in New World populations of the human malaria parasite Plasmodium vivax.

Science.gov (United States)

de Oliveira, Thais C; Rodrigues, Priscila T; Menezes, Maria José; Gonçalves-Lopes, Raquel M; Bastos, Melissa S; Lima, Nathália F; Barbosa, Susana; Gerber, Alexandra L; Loss de Morais, Guilherme; Berná, Luisa; Phelan, Jody; Robello, Carlos; de Vasconcelos, Ana Tereza R; Alves, João Marcelo P; Ferreira, Marcelo U

2017-07-01

The Americas were the last continent colonized by humans carrying malaria parasites. Plasmodium falciparum from the New World shows very little genetic diversity and greater linkage disequilibrium, compared with its African counterparts, and is clearly subdivided into local, highly divergent populations. However, limited available data have revealed extensive genetic diversity in American populations of another major human malaria parasite, P. vivax. We used an improved sample preparation strategy and next-generation sequencing to characterize 9 high-quality P. vivax genome sequences from northwestern Brazil. These new data were compared with publicly available sequences from recently sampled clinical P. vivax isolates from Brazil (BRA, total n = 11 sequences), Peru (PER, n = 23), Colombia (COL, n = 31), and Mexico (MEX, n = 19). We found that New World populations of P. vivax are as diverse (nucleotide diversity π between 5.2 × 10-4 and 6.2 × 10-4) as P. vivax populations from Southeast Asia, where malaria transmission is substantially more intense. They display several non-synonymous nucleotide substitutions (some of them previously undescribed) in genes known or suspected to be involved in antimalarial drug resistance, such as dhfr, dhps, mdr1, mrp1, and mrp-2, but not in the chloroquine resistance transporter ortholog (crt-o) gene. Moreover, P. vivax in the Americas is much less geographically substructured than local P. falciparum populations, with relatively little between-population genome-wide differentiation (pairwise FST values ranging between 0.025 and 0.092). Finally, P. vivax populations show a rapid decline in linkage disequilibrium with increasing distance between pairs of polymorphic sites, consistent with very frequent outcrossing. We hypothesize that the high diversity of present-day P. vivax lineages in the Americas originated from successive migratory waves and subsequent admixture between parasite lineages from geographically diverse sites

Incorporating Human Interindividual Biotransformation ...

Science.gov (United States)

The protection of sensitive individuals within a population dictates that measures other than central tendencies be employed to estimate risk. The refinement of human health risk assessments for chemicals metabolized by the liver to reflect data on human variability can be accomplished through (1) the characterization of enzyme expression in large banks of human liver samples, (2) the employment of appropriate techniques for the quantification and extrapolation of metabolic rates derived in vitro, and (3) the judicious application of physiologically based pharmacokinetic (PBPK) modeling. While in vitro measurements of specific biochemical reactions from multiple human samples can yield qualitatively valuable data on human variance, such measures must be put into the perspective of the intact human to yield the most valuable predictions of metabolic differences among humans. For quantitative metabolism data to be the most valuable in risk assessment, they must be tied to human anatomy and physiology, and the impact of their variance evaluated under real exposure scenarios. For chemicals metabolized in the liver, the concentration of parent chemical in the liver represents the substrate concentration in the MichaelisMenten description of metabolism. Metabolic constants derived in vitro may be extrapolated to the intact liver, when appropriate conditions are met. Metabolic capacity Vmax; the maximal rate of the reaction) can be scaled directly to the concentration

Deep Reflection on My Pedagogical Transformations

Science.gov (United States)

Suzawa, Gilbert S.

2014-01-01

This retrospective essay contains my reflection on the deep concept of ambiguity (uncertainty) and a concomitant epistemological theory that all of our human knowledge is ultimately self-referential in nature. This new epistemological perspective is subsequently utilized as a platform for gaining insights into my experiences in conjunction with…

Quantifying the demographic cost of human-related mortality to a raptor population

Science.gov (United States)

Hunt, W. Grainger; Wiens, David; Law, Peter R.; Fuller, Mark R.; Hunt, Teresa L.; Driscoll, Daniel E.; Jackman, Ronald E.

2017-01-01

Raptors are exposed to a wide variety of human-related mortality agents, and yet population-level effects are rarely quantified. Doing so requires modeling vital rates in the context of species life-history, behavior, and population dynamics theory. In this paper, we explore the details of such an analysis by focusing on the demography of a resident, tree-nesting population of golden eagles (Aquila chrysaetos) in the vicinity of an extensive (142 km2) windfarm in California. During 1994–2000, we tracked the fates of >250 radio-marked individuals of four life-stages and conducted five annual surveys of territory occupancy and reproduction. Collisions with wind turbines accounted for 41% of 88 uncensored fatalities, most of which were subadults and nonbreeding adults (floaters). A consistent overall male preponderance in the population meant that females were the limiting sex in this territorial, monogamous species. Estimates of potential population growth rate and associated variance indicated a stable breeding population, but one for which any further decrease in vital rates would require immigrant floaters to fill territory vacancies. Occupancy surveys 5 and 13 years later (2005 and 2013) showed that the nesting population remained intact, and no upward trend was apparent in the proportion of subadult eagles as pair members, a condition that would have suggested a deficit of adult replacements. However, the number of golden eagle pairs required to support windfarm mortality was large. We estimated that the entire annual reproductive output of 216–255 breeding pairs would have been necessary to support published estimates of 55–65 turbine blade-strike fatalities per year. Although the vital rates forming the basis for these calculations may have changed since the data were collected, our approach should be useful for gaining a clearer understanding of how anthropogenic mortality affects the health of raptor populations, particularly those species with delayed

Characteristics of reflected and diffuse ions upstream from the earth's bow shock

International Nuclear Information System (INIS)

Paschmann, G.; Sckopke, N.; Papamastorakis, I.; Asbridge, J.R.; Bame, S.J.; Gosling, J.T.

1981-01-01

The distinction between two types of upstream ion populations has been made on the basis of pronounced differences in their distribution functions. The 'reflected' ions represent a fast beam with temperatures typically 1 to 5 times 10 6 K and speeds up to five times the solar wind speed. An important feature of the reflected ion distributions in their strong temperature anisotropy, with T/sub perpendicular/ exceeding T/sub parallel/ by a factor of two to three. In contrast, the 'diffuse' ions occupy a much larger region of phase space, both in energy and angle; their distribution function generally has the form roughly of a circular ridge in 2 dimensions and a spherical shell in 3 dimensions. Accordingly, their temperature is much larger (> or approx. =10 7 K), and their bulk speed typically is smaller than the solar wind speed. Both ion populations have densities of the order of 0.1 cm -3 . At times transitions between the two extremes, represented by the reflected and diffuse ion populations, are observed. These 'intermediate' distributions are cresent shaped, with the center of curvature near the solar wind velocity. This property suggests that the intermediate distributions result from pitch angle scattering of the reflected beams in the solar wind frame and supports the idea that the reflected ions are the origin of the diffuse ions. At times the diffuse ion distributions exhibit considerable structure and rapid temporal variations. Reflected and diffuse ions can also be distinguished by their occurrence as a function of the angle theta between the local shock normal and the interplanetary magnetic field. Whereas the diffuse ions occur predominantly for small theta, the reflected ions are observed most frequently for theta> or approx. =45 0

Understanding Population.

Science.gov (United States)

Mothner, Ira

Activities and concerns of Ford Foundation supported population research and training centers are described in this report. The centers are concerned with population growth, consequences of growth for human welfare, forces that determine family planning, interrelations among population variables, economics of contraceptive distribution, and…

Intermingled Klebsiella pneumoniae Populations Between Retail Meats and Human Urinary Tract Infections

Science.gov (United States)

Davis, Gregg S.; Waits, Kara; Nordstrom, Lora; Weaver, Brett; Aziz, Maliha; Gauld, Lori; Grande, Heidi; Bigler, Rick; Horwinski, Joseph; Porter, Stephen; Stegger, Marc; Johnson, James R.; Liu, Cindy M.; Price, Lance B.

2015-01-01

Background. Klebsiella pneumoniae is a common colonizer of the gastrointestinal tract of humans, companion animals, and livestock. To better understand potential contributions of foodborne K. pneumoniae to human clinical infections, we compared K. pneumoniae isolates from retail meat products and human clinical specimens to assess their similarity based on antibiotic resistance, genetic relatedness, and virulence. Methods. Klebsiella pneumoniae was isolated from retail meats from Flagstaff grocery stores in 2012 and from urine and blood specimens from Flagstaff Medical Center in 2011–2012. Isolates underwent antibiotic susceptibility testing and whole-genome sequencing. Genetic relatedness of the isolates was assessed using multilocus sequence typing and phylogenetic analyses. Extraintestinal virulence of several closely related meat-source and urine isolates was assessed using a murine sepsis model. Results. Meat-source isolates were significantly more likely to be multidrug resistant and resistant to tetracycline and gentamicin than clinical isolates. Four sequence types occurred among both meat-source and clinical isolates. Phylogenetic analyses confirmed close relationships among meat-source and clinical isolates. Isolates from both sources showed similar virulence in the mouse sepsis model. Conclusions. Meat-source K. pneumoniae isolates were more likely than clinical isolates to be antibiotic resistant, which could reflect selective pressures from antibiotic use in food-animal production. The close genetic relatedness of meat-source and clinical isolates, coupled with similarities in virulence, suggest that the barriers to transmission between these 2 sources are low. Taken together, our results suggest that retail meat is a potential vehicle for transmitting virulent, antibiotic-resistant K. pneumoniae from food animals to humans. PMID:26206847

Signatures of natural selection at the FTO (fat mass and obesity associated locus in human populations.

Directory of Open Access Journals (Sweden)

Xuanshi Liu

Full Text Available Polymorphisms in the first intron of FTO have been robustly replicated for associations with obesity. In the Sorbs, a Slavic population resident in Germany, the strongest effect on body mass index (BMI was found for a variant in the third intron of FTO (rs17818902. Since this may indicate population specific effects of FTO variants, we initiated studies testing FTO for signatures of selection in vertebrate species and human populations.First, we analyzed the coding region of 35 vertebrate FTO orthologs with Phylogenetic Analysis by Maximum Likelihood (PAML, ω = dN/dS to screen for signatures of selection among species. Second, we investigated human population (Europeans/CEU, Yoruba/YRI, Chinese/CHB, Japanese/JPT, Sorbs SNP data for footprints of selection using DnaSP version 4.5 and the Haplotter/PhaseII. Finally, using ConSite we compared transcription factor (TF binding sites at sequences harbouring FTO SNPs in intron three.PAML analyses revealed strong conservation in coding region of FTO (ω<1. Sliding-window results from population genetic analyses provided highly significant (p<0.001 signatures for balancing selection specifically in the third intron (e.g. Tajima's D in Sorbs = 2.77. We observed several alterations in TF binding sites, e.g. TCF3 binding site introduced by the rs17818902 minor allele.Population genetic analysis revealed signatures of balancing selection at the FTO locus with a prominent signal in intron three, a genomic region with strong association with BMI in the Sorbs. Our data support the hypothesis that genes associated with obesity may have been under evolutionary selective pressure.

Trends in population-based studies of human genetics in infectious diseases.

Science.gov (United States)

Rowell, Jessica L; Dowling, Nicole F; Yu, Wei; Yesupriya, Ajay; Zhang, Lyna; Gwinn, Marta

2012-01-01

Pathogen genetics is already a mainstay of public health investigation and control efforts; now advances in technology make it possible to investigate the role of human genetic variation in the epidemiology of infectious diseases. To describe trends in this field, we analyzed articles that were published from 2001 through 2010 and indexed by the HuGE Navigator, a curated online database of PubMed abstracts in human genome epidemiology. We extracted the principal findings from all meta-analyses and genome-wide association studies (GWAS) with an infectious disease-related outcome. Finally, we compared the representation of diseases in HuGE Navigator with their contributions to morbidity worldwide. We identified 3,730 articles on infectious diseases, including 27 meta-analyses and 23 GWAS. The number published each year increased from 148 in 2001 to 543 in 2010 but remained a small fraction (about 7%) of all studies in human genome epidemiology. Most articles were by authors from developed countries, but the percentage by authors from resource-limited countries increased from 9% to 25% during the period studied. The most commonly studied diseases were HIV/AIDS, tuberculosis, hepatitis B infection, hepatitis C infection, sepsis, and malaria. As genomic research methods become more affordable and accessible, population-based research on infectious diseases will be able to examine the role of variation in human as well as pathogen genomes. This approach offers new opportunities for understanding infectious disease susceptibility, severity, treatment, control, and prevention.

Population Matters Policy Brief. Population and Environment. A Complex Relationship

National Research Council Canada - National Science Library

2000-01-01

.... In many ways, this reflected good news for humanity: child mortality rates plummeted, life expectancy increased, and people were on average healthier and better nourished than at any time in history...

3-Bromopyruvate inhibits cell proliferation and induces apoptosis in CD133+ population in human glioma.

Science.gov (United States)

Xu, Dong-Qiang; Tan, Xiao-Yu; Zhang, Bao-Wei; Wu, Tao; Liu, Ping; Sun, Shao-Jun; Cao, Yin-Guang

2016-03-01

The study was aimed to investigate the role of 3-bromopyruvate in inhibition of CD133+ U87 human glioma cell population growth. The results demonstrated that 3-bromopyruvate inhibited the viability of both CD133+ and parental cells derived from U87 human glioma cell line. However, the 3-bromopyruvate-induced inhibition in viability was more prominent in CD133+ cells at 10 μM concentration after 48 h. Treatment of CD133+ cells with 3-bromopyruvate caused reduction in cell population and cell size, membrane bubbling, and degradation of cell membranes. Hoechst 33258 staining showed condensation of chromatin material and fragmentation of DNA in treated CD133+ cells after 48 h. 3-Bromopyruvate inhibited the migration rate of CD133+ cells significantly compared to the parental cells. Flow cytometry revealed that exposure of CD133+ cells to 3-bromopyruvate increased the cell population in S phase from 24.5 to 37.9 % with increase in time from 12 to 48 h. In addition, 3-bromopyruvate significantly enhanced the expression of Bax and cleaved caspase 3 in CD133+ cells compared to the parental cells. Therefore, 3-bromopyruvate is a potent chemotherapeutic agent for the treatment of glioma by targeting stem cells selectively.

The variation field of the radiosensitivity in the human population: hypersensitivity and hypo sensitivity

International Nuclear Information System (INIS)

Bouffler, S.

2009-01-01

It is generally admitted in the radiotherapy practice that 5% of patients will present serious reactions of normal tissues. Studies made on human population confirm it exists variations of cell radiosensitivity and genetic factors contribute in a significant manner to the observed variations. The researches of markers able to predict the reactions of normal tissues to the therapy focussed on the identification of sensitive sub-group. It is however obvious that exists also a part of the population relatively hypo sensitive. It would be interesting to make studies on the genome to find genes associated to serious reactions of normal tissues to radiotherapy. (N.C.)

Teachers' Professional Development from the Perspective of Teaching Reflection Levels

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Zhao, Mingren

2012-01-01

This paper is a case study based on Habermas's theory of knowledge and human interest. We analyzed the written reflections of four teachers employed at a school and found that the teachers who had experienced advanced professional development tended to engage in practical and critical reflection, whereas those who had experienced average…

Inferring genome-wide patterns of admixture in Qataris using fifty-five ancestral populations

Directory of Open Access Journals (Sweden)

Omberg Larsson

2012-06-01

Full Text Available Abstract Background Populations of the Arabian Peninsula have a complex genetic structure that reflects waves of migrations including the earliest human migrations from Africa and eastern Asia, migrations along ancient civilization trading routes and colonization history of recent centuries. Results Here, we present a study of genome-wide admixture in this region, using 156 genotyped individuals from Qatar, a country located at the crossroads of these migration patterns. Since haplotypes of these individuals could have originated from many different populations across the world, we have developed a machine learning method "SupportMix" to infer loci-specific genomic ancestry when simultaneously analyzing many possible ancestral populations. Simulations show that SupportMix is not only more accurate than other popular admixture discovery tools but is the first admixture inference method that can efficiently scale for simultaneous analysis of 50-100 putative ancestral populations while being independent of prior demographic information. Conclusions By simultaneously using the 55 world populations from the Human Genome Diversity Panel, SupportMix was able to extract the fine-scale ancestry of the Qatar population, providing many new observations concerning the ancestry of the region. For example, as well as recapitulating the three major sub-populations in Qatar, composed of mainly Arabic, Persian, and African ancestry, SupportMix additionally identifies the specific ancestry of the Persian group to populations sampled in Greater Persia rather than from China and the ancestry of the African group to sub-Saharan origin and not Southern African Bantu origin as previously thought.

Monte Carlo simulation of spectral reflectance and BRDF of the bubble layer in the upper ocean.

Science.gov (United States)

Ma, Lanxin; Wang, Fuqiang; Wang, Chengan; Wang, Chengchao; Tan, Jianyu

2015-09-21

The presence of bubbles can significantly change the radiative properties of seawater and these changes will affect remote sensing and underwater target detection. In this work, the spectral reflectance and bidirectional reflectance characteristics of the bubble layer in the upper ocean are investigated using the Monte Carlo method. The Hall-Novarini (HN) bubble population model, which considers the effect of wind speed and depth on the bubble size distribution, is used. The scattering coefficients and the scattering phase functions of bubbles in seawater are calculated using Mie theory, and the inherent optical properties of seawater for wavelengths between 300 nm and 800 nm are related to chlorophyll concentration (Chl). The effects of bubble coating, Chl, and bubble number density on the spectral reflectance of the bubble layer are studied. The bidirectional reflectance distribution function (BRDF) of the bubble layer for both normal and oblique incidence is also investigated. The results show that bubble populations in clear waters under high wind speed conditions significantly influence the reflection characteristics of the bubble layer. Furthermore, the contribution of bubble populations to the reflection characteristics is mainly due to the strong backscattering of bubbles that are coated with an organic film.

Simulating reflectance at interfaces coated with household paints

Science.gov (United States)

Prisland, Zachary

The paint and coatings industry is constantly working to improve their product, making a more efficient product at a cheaper cost. This requires some research and learning on the part of the companies, particularly in optical studies. For example, Burgess Pigment Company has developed a method, using a flash calciner, to quickly dehydrate clay, essentially popping it like popcorn, in order to add air pockets to the individual particles of clay. Clay that has undergone this process can improve the reflective properties of paint. The human eye, as a sensory organ, relies on reflected light in order to provide vision. As the major goal of paint is to be seen, it is easy to infer that it would be of utmost importance for the paint to reflect large amounts of light to appear more visible to the human eye and so using clay that has air pockets would be more desirable. The primary goal of this thesis will be to explore optical theory in an attempt to explain why the addition of air pockets could produce a more effective product.