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Showing papers on "Population published in 2000"


Journal ArticleDOI
01 Jun 2000-Genetics
TL;DR: Pritch et al. as discussed by the authors proposed a model-based clustering method for using multilocus genotype data to infer population structure and assign individuals to populations, which can be applied to most of the commonly used genetic markers, provided that they are not closely linked.
Abstract: We describe a model-based clustering method for using multilocus genotype data to infer population structure and assign individuals to populations. We assume a model in which there are K populations (where K may be unknown), each of which is characterized by a set of allele frequencies at each locus. Individuals in the sample are assigned (probabilistically) to populations, or jointly to two or more populations if their genotypes indicate that they are admixed. Our model does not assume a particular mutation process, and it can be applied to most of the commonly used genetic markers, provided that they are not closely linked. Applications of our method include demonstrating the presence of population structure, assigning individuals to populations, studying hybrid zones, and identifying migrants and admixed individuals. We show that the method can produce highly accurate assignments using modest numbers of loci— e.g. , seven microsatellite loci in an example using genotype data from an endangered bird species. The software used for this article is available from http://www.stats.ox.ac.uk/~pritch/home.html.

27,454 citations


Journal ArticleDOI
06 May 2000-BMJ
TL;DR: The proposed cut off points, which are less arbitrary and more internationally based than current alternatives, should help to provide internationally comparable prevalence rates of overweight and obesity in children.
Abstract: Objective To develop an internationally acceptable definition of child overweight and obesity, specifying the measurement, the reference population, and the age and sex specific cut off points. Design International survey of six large nationally representative cross sectional growth studies. Setting Brazil, Great Britain, Hong Kong, the Netherlands, Singapore, and the United States. Subjects 97 876 males and 94 851 females from birth to 25 years of age. Main outcome measure Body mass index (weight/height 2 ). Results For each of the surveys, centile curves were drawn that at age 18 years passed through the widely used cut off points of 25 and 30 kg/m 2 for adult overweight and obesity. The resulting curves were averaged to provide age and sex specific cut off points from 2›18 years. Conclusions The proposed cut off points, which are less arbitrary and more internationally based than current alternatives, should help to provide internationally comparable prevalence rates of overweight and obesity in children.

14,792 citations


Journal ArticleDOI
22 Jun 2000-Nature
TL;DR: The present genetic structure of populations, species and communities has been mainly formed by Quaternary ice ages, and genetic, fossil and physical data combined can greatly help understanding of how organisms were so affected.
Abstract: Global climate has fluctuated greatly during the past three million years, leading to the recent major ice ages. An inescapable consequence for most living organisms is great changes in their distribution, which are expressed differently in boreal, temperate and tropical zones. Such range changes can be expected to have genetic consequences, and the advent of DNA technology provides most suitable markers to examine these. Several good data sets are now available, which provide tests of expectations, insights into species colonization and unexpected genetic subdivision and mixture of species. The genetic structure of human populations may be viewed in the same context. The present genetic structure of populations, species and communities has been mainly formed by Quaternary ice ages, and genetic, fossil and physical data combined can greatly help our understanding of how organisms were so affected.

6,341 citations


Book ChapterDOI
20 Jul 2000
TL;DR: The relation of the society outside organizations to the internal life of organizations is discussed in this article, where the authors focus on the effects of organizational variables on the surrounding social environment, including groups, institutions, laws, population characteristics, and sets of social relations that form the environment of the organization.
Abstract: The general topic of this chapter is the relation of the society outside organizations to the internal life of organizations Part of the specific topics have to do with the effect of society on organizations, and part of them concern the effects of organizational variables on the surrounding social environment I intend to interpret the term “social structure” in the title in a very general sense, to include groups, institutions, laws, population characteristics, and sets of social relations that form the environment of the organization That is, I interpret “social structure” to mean any variables which are stable characteristics of the society outside the organization By an “organization” I mean a set of stable social relations deliberately created, with the explicit intention of continuously accomplishing some specific goals or purposes These goals or purposes are generally functions performed for some larger structure For example, armies have the goal of winning possible military engagements The fulfillment of this goal is a function performed for the larger political structure, which has functional requirements of defense and conquest I exclude from organizations many types of groups which have multiple purposes (or which perform multiple functions for larger systems, whether these are anyone's purposes or not), such as families, geographical communities, ethnic groups, or total societies 1 also exclude social arrangements built up on the spur of the moment to achieve some specific short-run purpose For instance, I will not consider a campaign committee for some political candidate as an “organization,” although a political party would definitely meet the criterion of continuous functioning and relatively specific purposes

5,017 citations


Journal ArticleDOI
06 Apr 2000-Nature
TL;DR: The global epidemic of obesity results from a combination of genetic susceptibility, increased availability of high-energy foods and decreased requirement for physical activity in modern society, and should be regarded as an epidemic that threatens global well being.
Abstract: Obesity is now so common within the world's population that it is beginning to replace undernutrition and infectious diseases as the most significant contributor to ill health. In particular, obesity is associated with diabetes mellitus, coronary heart disease, certain forms of cancer, and sleep-breathing disorders. Obesity is defined by a body-mass index (weight divided by square of the height) of 30 kg m(-2) or greater, but this does not take into account the morbidity and mortality associated with more modest degrees of overweight, nor the detrimental effect of intra-abdominal fat. The global epidemic of obesity results from a combination of genetic susceptibility, increased availability of high-energy foods and decreased requirement for physical activity in modern society. Obesity should no longer be regarded simply as a cosmetic problem affecting certain individuals, but an epidemic that threatens global well being.

4,697 citations


Journal ArticleDOI
15 Nov 2000-Spine
TL;DR: The ODI remains a valid and vigorous measure and has been a worthwhile outcome measure, and the process of using the ODI is reviewed and should be the subject of further research.
Abstract: Study design The Oswestry Disability Index (ODI) has become one of the principal condition-specific outcome measures used in the management of spinal disorders. This review is based on publications using the ODI identified from the authors' personal databases, the Science Citation Index, and hand searches of Spine and current textbooks of spinal disorders. Objectives To review the versions of this instrument, document methods by which it has been validated, collate data from scores found in normal and back pain populations, provide curves for power calculations in studies using the ODI, and maintain the ODI as a gold standard outcome measure. Summary of background data It has now been 20 years since its original publication. More than 200 citations exist in the Science Citation Index. The authors have a large correspondence file relating to the ODI, that is cited in most of the large textbooks related to spinal disorders. Methods All the published versions of the questionnaire were identified. A systematic review of this literature was made. The various reports of validation were collated and related to a version. Results Four versions of the ODI are available in English and nine in other languages. Some published versions contain misprints, and many omit the scoring system. At least 114 studies contain usable data. These data provide both validation and standards for other users and indicate the power of the instrument for detecting change in sample populations. Conclusions The ODI remains a valid and vigorous measure and has been a worthwhile outcome measure. The process of using the ODI is reviewed and should be the subject of further research. The receiver operating characteristics should be explored in a population with higher self-report disabilities. The behavior of the instrument is incompletely understood, particularly in sensitivity to real change.

4,482 citations


Journal ArticleDOI
TL;DR: A dose-response association between sleep-disordered breathing at base line and the presence of hypertension four years later was found that was independent of known confounding factors and suggest that sleep- disordered breathing is likely to be a risk factor for hypertension and consequent cardiovascular morbidity in the general population.
Abstract: Background Sleep-disordered breathing is prevalent in the general population and has been linked to chronically elevated blood pressure in cross-sectional epidemiologic studies. We performed a prospective, population-based study of the association between objectively measured sleep-disordered breathing and hypertension (defined as a laboratory-measured blood pressure of at least 140/90 mm Hg or the use of antihypertensive medications). Methods We analyzed data on sleep-disordered breathing, blood pressure, habitus, and health history at base line and after four years of follow-up in 709 participants of the Wisconsin Sleep Cohort Study (and after eight years of follow-up in the case of 184 of these participants). Participants were assessed overnight by 18-channel polysomnography for sleep-disordered breathing, as defined by the apnea–hypopnea index (the number of episodes of apnea and hypopnea per hour of sleep). The odds ratios for the presence of hypertension at the four-year follow-up study according to...

4,429 citations


Journal ArticleDOI
TL;DR: Although the Ki‐67 protein is well characterized on the molecular level and extensively used as a proliferation marker, the functional significance still remains unclear; there are indications, however, that Ki‐ 67 protein expression is an absolute requirement for progression through the cell‐division cycle.
Abstract: The expression of the human Ki-67 protein is strictly associated with cell proliferation. During interphase, the antigen can be exclusively detected within the nucleus, whereas in mitosis most of the protein is relocated to the surface of the chromosomes. The fact that the Ki-67 protein is present during all active phases of the cell cycle (G(1), S, G(2), and mitosis), but is absent from resting cells (G(0)), makes it an excellent marker for determining the so-called growth fraction of a given cell population. In the first part of this study, the term proliferation marker is discussed and examples of the applications of anti-Ki-67 protein antibodies in diagnostics of human tumors are given. The fraction of Ki-67-positive tumor cells (the Ki-67 labeling index) is often correlated with the clinical course of the disease. The best-studied examples in this context are carcinomas of the prostate and the breast. For these types of tumors, the prognostic value for survival and tumor recurrence has repeatedly been proven in uni- and multivariate analysis. The preparation of new monoclonal antibodies that react with the Ki-67 equivalent protein from rodents now extends the use of the Ki-67 protein as a proliferation marker to laboratory animals that are routinely used in basic research. The second part of this review focuses on the biology of the Ki-67 protein. Our current knowledge of the Ki-67 gene and protein structure, mRNA splicing, expression, and cellular localization during the cell-division cycle is summarized and discussed. Although the Ki-67 protein is well characterized on the molecular level and extensively used as a proliferation marker, the functional significance still remains unclear. There are indications, however, that Ki-67 protein expression is an absolute requirement for progression through the cell-division cycle.

4,359 citations


Journal ArticleDOI
14 Jul 2000-Science
TL;DR: Numerical experiments combining climate model outputs, water budgets, and socioeconomic information along digitized river networks demonstrate that (i) a large proportion of the world's population is currently experiencing water stress and (ii) rising water demands greatly outweigh greenhouse warming in defining the state of global water systems to 2025.
Abstract: The future adequacy of freshwater resources is difficult to assess, owing to a complex and rapidly changing geography of water supply and use. Numerical experiments combining climate model outputs, water budgets, and socioeconomic information along digitized river networks demonstrate that (i) a large proportion of the world's population is currently experiencing water stress and (ii) rising water demands greatly outweigh greenhouse warming in defining the state of global water systems to 2025. Consideration of direct human impacts on global water supply remains a poorly articulated but potentially important facet of the larger global change question.

4,355 citations


Journal ArticleDOI
TL;DR: Postnatal human DPSCs are isolated that have the ability to form a dentin/pulp-like complex and are compared with human bone marrow stromal cells, known precursors of osteoblasts.
Abstract: Dentinal repair in the postnatal organism occurs through the activity of specialized cells, odontoblasts, that are thought to be maintained by an as yet undefined precursor population associated with pulp tissue. In this study, we isolated a clonogenic, rapidly proliferative population of cells from adult human dental pulp. These DPSCs were then compared with human bone marrow stromal cells (BMSCs), known precursors of osteoblasts. Although they share a similar immunophenotype in vitro, functional studies showed that DPSCs produced only sporadic, but densely calcified nodules, and did not form adipocytes, whereas BMSCs routinely calcified throughout the adherent cell layer with clusters of lipid-laden adipocytes. When DPSCs were transplanted into immunocompromised mice, they generated a dentin-like structure lined with human odontoblast-like cells that surrounded a pulp-like interstitial tissue. In contrast, BMSCs formed lamellar bone containing osteocytes and surface-lining osteoblasts, surrounding a fibrous vascular tissue with active hematopoiesis and adipocytes. This study isolates postnatal human DPSCs that have the ability to form a dentin/pulp-like complex.

4,174 citations


Posted Content
TL;DR: In this paper, the authors presented a data set that improves the measurement of educational attainment for a broad group of countries, and extended their previous estimates for the population over age 15 and over age 25 up to 1995 and provided projections for 2000.
Abstract: This paper presents a data set that improves the measurement of educational attainment for a broad group of countries. We extend our previous estimates of educational attainment for the population over age 15 and over age 25 up to 1995 and provide projections for 2000. We discuss the estimation method for the measures of educational attainment and relate our estimates to alternative international measures of human capital stocks.

Journal ArticleDOI
TL;DR: How factors such as ethnicity, economic status, educational level, sexual orientation and social context influence the kind of masculinity that men construct and contribute to differential health risks among men in the United States is explored.

Journal ArticleDOI
TL;DR: GA's population-based approach and ability to make pair-wise comparison in tournament selection operator are exploited to devise a penalty function approach that does not require any penalty parameter to guide the search towards the constrained optimum.

MonographDOI
TL;DR: In this paper, the authors discuss the relationship between political regimes and economic growth in the United States and discuss the dynamics of political regimes, economic growth, political instability, and population.
Abstract: Introduction 1. Democracies and dictatorships 2. Dynamic of political regimes 3. Political regimes and economic growth 4. Political instability and economic growth 5. Political regimes and population Conclusion.

Journal ArticleDOI
TL;DR: Irinotecan combined with fluorouracil and calcium folinate was well-tolerated and increased response rate, time to progression, and survival, with a later deterioration in quality of life.

Journal ArticleDOI
TL;DR: The identity of Alamar Blue is shown as resazurin, a very simple and versatile way of measuring cell proliferation and cytotoxicity that presents numerous advantages over other cytot toxicity or proliferation tests but there are several drawbacks to the routine use.
Abstract: We show here the identity of Alamar Blue as resazurin. The 'resazurin reduction test' has been used for about 50 years to monitor bacterial and yeast contamination of milk, and also for assessing semen quality. Resazurin (blue and nonfluorescent) is reduced to resorufin (pink and highly fluorescent) which is further reduced to hydroresorufin (uncoloured and nonfluorescent). It is still not known how this reduction occurs, intracellularly via enzyme activity or in the medium as a chemical reaction, although the reduced fluorescent form of Alamar Blue was found in the cytoplasm and of living cells nucleus of dead cells. Recently, the dye has gained popularity as a very simple and versatile way of measuring cell proliferation and cytotoxicity. This dye presents numerous advantages over other cytotoxicity or proliferation tests but we observed several drawbacks to the routine use of Alamar Blue. Tests with several toxicants in different cell lines and rat primary hepatocytes have shown accumulation of the fluorescent product of Alamar Blue in the medium which could lead to an overestimation of cell population. Also, the extensive reduction of Alamar Blue by metabolically active cells led to a final nonfluorescent product, and hence an underestimation of cellular activity.

Journal ArticleDOI
12 Apr 2000-JAMA
TL;DR: The findings from the largest cross-sectional study to date indicate that SDB is associated with systemic hypertension in middle-aged and older individuals of different sexes and ethnic backgrounds.
Abstract: ContextSleep-disordered breathing (SDB) and sleep apnea have been linked to hypertension in previous studies, but most of these studies used surrogate information to define SDB (eg, snoring) and were based on small clinic populations, or both.ObjectiveTo assess the association between SDB and hypertension in a large cohort of middle-aged and older persons.Design and SettingCross-sectional analyses of participants in the Sleep Heart Health Study, a community-based multicenter study conducted between November 1995 and January 1998.ParticipantsA total of 6132 subjects recruited from ongoing population-based studies (aged ≥40 years; 52.8% female).Main Outcome MeasuresApnea-hypopnea index (AHI, the average number of apneas plus hypopneas per hour of sleep, with apnea defined as a cessation of airflow and hypopnea defined as a ≥30% reduction in airflow or thoracoabdominal excursion both of which are accompanied by a ≥4% drop in oxyhemoglobin saturation), obtained by unattended home polysomnography. Other measures include arousal index; percentage of sleep time below 90% oxygen saturation; history of snoring; and presence of hypertension, defined as resting blood pressure of at least 140/90 mm Hg or use of antihypertensive medication.ResultsMean systolic and diastolic blood pressure and prevalence of hypertension increased significantly with increasing SDB measures, although some of this association was explained by body mass index (BMI). After adjusting for demographics and anthropometric variables (including BMI, neck circumference, and waist-to-hip ratio), as well as for alcohol intake and smoking, the odds ratio for hypertension, comparing the highest category of AHI (≥30 per hour) with the lowest category (<1.5 per hour), was 1.37 (95% confidence interval [CI], 1.03-1.83; P for trend=.005). The corresponding estimate comparing the highest and lowest categories of percentage of sleep time below 90% oxygen saturation (≥12% vs <0.05%) was 1.46 (95% CI, 1.12-1.88; P for trend <.001). In stratified analyses, associations of hypertension with either measure of SDB were seen in both sexes, older and younger ages, all ethnic groups, and among normal-weight and overweight individuals. Weaker and nonsignificant associations were observed for the arousal index or self-reported history of habitual snoring.ConclusionOur findings from the largest cross-sectional study to date indicate that SDB is associated with systemic hypertension in middle-aged and older individuals of different sexes and ethnic backgrounds.

Journal ArticleDOI
TL;DR: The viral load is the chief predictor of the risk of heterosexual transmission of HIV-1, and transmission is rare among persons with levels of less than 1500 copies of HIV -1 RNA per milliliter.
Abstract: Background and Methods We examined the influence of viral load in relation to other risk factors for the heterosexual transmission of human immunodeficiency virus type 1 (HIV-1). In a community-based study of 15,127 persons in a rural district of Uganda, we identified 415 couples in which one partner was HIV-1–positive and one was initially HIV-1–negative and followed them prospectively for up to 30 months. The incidence of HIV-1 infection per 100 person-years among the initially seronegative partners was examined in relation to behavioral and biologic variables. Results The male partner was HIV-1–positive in 228 couples, and the female partner was HIV-1–positive in 187 couples. Ninety of the 415 initially HIV-1–negative partners seroconverted (incidence, 11.8 per 100 person-years). The rate of male-to-female transmission was not significantly different from the rate of female-to-male transmission (12.0 per 100 person-years vs. 11.6 per 100 person-years). The incidence of seroconversion was highest among ...


Journal ArticleDOI
TL;DR: Meta-analytic techniques used to test whether trait consistency maximizes and stabilizes at a specific period in the life course showed that the longitudinal time interval had a negative relation to trait consistency and that temperament dimensions were less consistent than adult personality traits.
Abstract: The present study used meta-analytic techniques to test whether trait consistency maximizes and stabilizes at a specific period in the life course. From 152 longitudinal studies, 3,217 test-retest correlation coefficients were compiled. Meta-analytic estimates of mean population test-retest correlation coefficients showed that trait consistency increased from .31 in childhood to .54 during the college years, to .64 at age 30, and then reached a plateau around .74 between ages 50 and 70 when time interval was held constant at 6.7 years. Analysis of moderators of consistency showed that the longitudinal time interval had a negative relation to trait consistency and that temperament dimensions were less consistent than adult personality traits.

Journal ArticleDOI
TL;DR: The results confirm that thyroid dysfunction is common, may often go undetected, and may be associated with adverse health outcomes that can be avoided by serum TSH measurement.
Abstract: Context: The prevalence of abnormal thyroid function in the United States and the significance of thyroid dysfunction remain controversial. Systemic effects of abnormal thyroid function have not been fully delineated, particularly in cases of mild thyroid failure. Also, the relationship between traditional hypothyroid symptoms and biochemical thyroid function is unclear. Objective: To determine the prevalence of abnormal thyroid function and the relationship between (1) abnormal thyroid function and lipid levels and (2) abnormal thyroid function and symptoms using modern and sensitive thyroid tests. Design: Cross-sectional study.

Journal ArticleDOI
TL;DR: Roads are a widespread and increasing feature of most landscapes. as mentioned in this paper reviewed the scientific liter- ature on the ecological effects of roads and found support for the general conclusion that they are associated with negative effects on biotic integrity in both terrestrial and aquatic ecosystems.
Abstract: Roads are a widespread and increasing feature of most landscapes. We reviewed the scientific liter- ature on the ecological effects of roads and found support for the general conclusion that they are associated with negative effects on biotic integrity in both terrestrial and aquatic ecosystems. Roads of all kinds have seven general effects: mortality from road construction, mortality from collision with vehicles, modification of animal behavior, alteration of the physical environment, alteration of the chemical environment, spread of exotics, and increased use of areas by humans. Road construction kills sessile and slow-moving organisms, injures organisms adjacent to a road, and alters physical conditions beneath a road. Vehicle collisions affect the demography of many species, both vertebrates and invertebrates; mitigation measures to reduce roadkill have been only partly successful. Roads alter animal behavior by causing changes in home ranges, move- ment, reproductive success, escape response, and physiological state. Roads change soil density, temperature, soil water content, light levels, dust, surface waters, patterns of runoff, and sedimentation, as well as adding heavy metals (especially lead), salts, organic molecules, ozone, and nutrients to roadside environments. Roads promote the dispersal of exotic species by altering habitats, stressing native species, and providing movement corridors. Roads also promote increased hunting, fishing, passive harassment of animals, and landscape modifications. Not all species and ecosystems are equally affected by roads, but overall the pres- ence of roads is highly correlated with changes in species composition, population sizes, and hydrologic and geomorphic processes that shape aquatic and riparian systems. More experimental research is needed to com- plement post-hoc correlative studies. Our review underscores the importance to conservation of avoiding con- struction of new roads in roadless or sparsely roaded areas and of removal or restoration of existing roads to benefit both terrestrial and aquatic biota.

Journal ArticleDOI
TL;DR: In this article, the relation of C-reactive protein (CRP), fibrinogen, and white cell count to components of the insulin resistance syndrome (IRS) in the nondiabetic population of the Insulin Resistance Atherosclerosis Study (IRAS) (n=1008; age, 40 to 69 years; 33% with impaired glucose tolerance), was investigated.
Abstract: Background—Inflammation has been suggested as a risk factor for the development of atherosclerosis. Recently, some components of the insulin resistance syndrome (IRS) have been related to inflammatory markers. We hypothesized that insulin insensitivity, as directly measured, may be associated with inflammation in nondiabetic subjects. Methods and Results—We studied the relation of C-reactive protein (CRP), fibrinogen, and white cell count to components of IRS in the nondiabetic population of the Insulin Resistance Atherosclerosis Study (IRAS) (n=1008; age, 40 to 69 years; 33% with impaired glucose tolerance), a multicenter, population-based study. None of the subjects had clinical coronary artery disease. Insulin sensitivity (SI) was measured by a frequently sampled intravenous glucose tolerance test, and CRP was measured by a highly sensitive competitive immunoassay. All 3 inflammatory markers were correlated with several components of the IRS. Strong associations were found between CRP and measures of b...

Journal ArticleDOI
TL;DR: In its current basic form the CBMN assay can provide the following measures of genotoxicity and cytotoxicity: chromosome breakage, chromosome loss, chromosome rearrangement, cell division inhibition, necrosis and apoptosis.
Abstract: The study of DNA damage at the chromosome level is an essential part of genetic toxicology because chromosomal mutation is an important event in carcinogenesis. The micronucleus assays have emerged as one of the preferred methods for assessing chromosome damage because they enable both chromosome loss and chromosome breakage to be measured reliably. Because micronuclei can only be expressed in cells that complete nuclear division a special method was developed that identifies such cells by their binucleate appearance when blocked from performing cytokinesis by cytochalasin-B (Cyt-B), a microfilament-assembly inhibitor. The cytokinesis-block micronucleus (CBMN) assay allows better precision because the data obtained are not confounded by altered cell division kinetics caused by cytotoxicity of agents tested or sub-optimal cell culture conditions. The method is now applied to various cell types for population monitoring of genetic damage, screening of chemicals for genotoxic potential and for specific purposes such as the prediction of the radiosensitivity of tumours and the inter-individual variation in radiosensitivity. In its current basic form the CBMN assay can provide, using simple morphological criteria, the following measures of genotoxicity and cytotoxicity: chromosome breakage, chromosome loss, chromosome rearrangement (nucleoplasmic bridges), cell division inhibition, necrosis and apoptosis. The cytosine-arabinoside modification of the CBMN assay allows for measurement of excision repairable lesions. The use of molecular probes enables chromosome loss to be distinguished from chromosome breakage and importantly non-disjunction in non-micronucleated binucleated cells can be efficiently measured. The in vitro CBMN technique, therefore, provides multiple and complementary measures of genotoxicity and cytotoxicity which can be achieved with relative ease within one system. The basic principles and methods (including detailed scoring criteria for all the genotoxicity and cytotoxicity end-points) of the CBMN assay are described and areas for future development identified.

Journal ArticleDOI
TL;DR: The African Middle and early Late Pleistocene hominid fossil record is fairly continuous and in it can be recognized a number of probably distinct species that provide plausible ancestors for H. sapiens, and suggests a gradual assembling of the package of modern human behaviors in Africa, and its later export to other regions of the Old World.

Journal ArticleDOI
TL;DR: The Pareto Archived Evolution Strategy (PAES) as discussed by the authors is a (1 + 1) evolution strategy employing local search but using a reference archive of previously found solutions in order to identify the approximate dominance ranking of the current and candidate solution vectors.
Abstract: We introduce a simple evolution scheme for multiobjective optimization problems, called the Pareto Archived Evolution Strategy (PAES) We argue that PAES may represent the simplest possible nontrivial algorithm capable of generating diverse solutions in the Pareto optimal set The algorithm, in its simplest form, is a (1 + 1) evolution strategy employing local search but using a reference archive of previously found solutions in order to identify the approximate dominance ranking of the current and candidate solution vectors (1 + 1)-PAES is intended to be a baseline approach against which more involved methods may be compared It may also serve well in some real-world applications when local search seems superior to or competitive with population-based methods We introduce (1 + λ) and (μ | λ) variants of PAES as extensions to the basic algorithm Six variants of PAES are compared to variants of the Niched Pareto Genetic Algorithm and the Nondominated Sorting Genetic Algorithm over a diverse suite of six test functions Results are analyzed and presented using techniques that reduce the attainment surfaces generated from several optimization runs into a set of univariate distributions This allows standard statistical analysis to be carried out for comparative purposes Our results provide strong evidence that PAES performs consistently well on a range of multiobjective optimization tasks

01 Jan 2000
TL;DR: The World Health Organization (WHO) adopted a standard based on the average age-structure of those populations to be compared (the world) over the likely period of time that a new standard will be used (some 25-30 years), using the latest UN assessment for 1998 (UN Population Division, 1998) from these estimates, an average world population agestructure was constructed for the period 2000-2025 as discussed by the authors.
Abstract: Summary A recent WHO analysis has revealed the need for a new world standard population (see attached table). This has become particularly pertinent given the rapid and continued declines in age-specific mortality rates among the oldest old, and the increasing availability of epidemiological data for higher age groups. There is clearly no conceptual justification for choosing one standard over another, hence the choice is arbitrary. However, choosing a standard population with higher proportions in the younger age groups tends to weight events at these ages disproportionately. Similarly, choosing an older standard does the opposite. Hence, rather than selecting a standard to match the current age-structure of some population(s), the WHO adopted a standard based on the average age-structure of those populations to be compared (the world) over the likely period of time that a new standard will be used (some 25-30 years), using the latest UN assessment for 1998 (UN Population Division, 1998). From these estimates, an average world population age-structure was constructed for the period 2000-2025. The use of an average world population, as well as a time series of observations, removes the effects of historical events such as wars and famine on population age composition. The terminal age group in the new WHO standard population has been extended out to 100 years and over, rather than the 85 and over as is the current practice. The WHO World Standard population has fewer children and notably more adults aged 70 and above than the world standard. It is also notably younger than the European standard. It is important to note, however, that the age standardized death rates based on the new standard are not comparable to previous estimates that are based on some earlier standard(s). However, to facilitate comparative analyses, WHO will disseminate trend analyses of the “complete” historical mortality data using on the new WHO World Standard Population in future editions of the World Health Statistics Annual.

Book
15 Mar 2000
TL;DR: The Basic Reproduction Ratio (RBR) as mentioned in this paper is a variant of the Kermack-McKendrick ODE model, and it has been used to model population dynamics at the Demographic Time Scale.
Abstract: Preface, Creed and Apology. What it is All About and What Not. The Top Down Approach. A Workbook. Portrait of the Reader as a Young Person. A Brief Outline of the Book. Acknowledgments. And What About Reality? I: THE BARE BONES: BASIC ISSUES EXPLAINED IN THE SIMPLEST CONTEXT. The Epidemic in a Closed Population. Heterogeneity: The Art of Averaging. Dynamics at the Demographic Time Scale. II: STRUCTURED POPULATIONS. The Concept of State. The Basic Reproduction Ratio. And Everything Else... Age Structure. Spatial Spread. Macroparasites. What is Contact? III: THE HARD PART: ELABORATIONS (ALMOST) ALL EXERCISES. Elaborations for Part I. Elaborations for Part II. Appendix A: Stochastic Basic of the Kermack-McKendrick ODE Model. Appendix B: Bibliographic Skeleton. Index.

Journal ArticleDOI
TL;DR: Ex vivo expanded hEPCs may have utility as a "supply-side" strategy for therapeutic neovascularization in mice with hindlimb ischemia and the rate of limb loss was significantly reduced.
Abstract: Animal studies and preliminary results in humans suggest that lower extremity and myocardial ischemia can be attenuated by treatment with angiogenic cytokines. The resident population of endothelial cells that is competent to respond to an available level of angiogenic growth factors, however, may potentially limit the extent to which cytokine supplementation enhances tissue neovascularization. Accordingly, we transplanted human endothelial progenitor cells (hEPCs) to athymic nude mice with hindlimb ischemia. Blood flow recovery and capillary density in the ischemic hindlimb were markedly improved, and the rate of limb loss was significantly reduced. Ex vivo expanded hEPCs may thus have utility as a “supply-side” strategy for therapeutic neovascularization.

Book
01 Jan 2000
TL;DR: In this paper, David Harvey brings an exciting perspective to two of the principal themes of contemporary social discourse: globalization and the body, and places the working body in relation to this new geography, finding in Marx's writings a wealth of relevant analysis and theoretical insight.
Abstract: As the twentieth century drew to a close, the rich were getting richer; power was concentrating within huge corporations; vast tracts of the earth were being laid waste; and, three quarters of the earth's population had no control over its destiny and no claim to basic rights. There was nothing new in this. What was new was the virtual absence of any political will to do anything about it. "Spaces of Hope" takes issue with this. David Harvey brings an exciting perspective to two of the principal themes of contemporary social discourse: globalization and the body. Exploring the uneven geographical development of late-twentieth-century capitalism, and placing the working body in relation to this new geography, he finds in Marx's writings a wealth of relevant analysis and theoretical insight. In order to make much-needed changes, Harvey maintains, we need to become the architects of a different living and working environment and to learn to bridge the micro-scale of the body and the personal and the macro-scale of global political economy. Utopian movements have for centuries tried to construct a just society. Harvey looks at their history to ask why they failed and what the ideas behind them might still have to offer. His devastating description of the existing urban environment (Baltimore is his case study) fuels his argument that we can and must use the force of utopian imagining against all who say 'there is no alternative'. He outlines a new kind of utopian thought, which he calls dialectical utopianism, and refocuses our attention on possible designs for a more equitable world of work and living with nature. If any political ideology or plan is to work, he argues, it must take account of our human qualities. Finally, Harvey dares to sketch a very personal utopian vision in an appendix, one that leaves no doubt about his own geography of hope.