Milne, Roger L; John, Esther M; Knight, Julia A; Dite, Gillian S; Southey, Melissa C; Giles, Graham G; Apicella, Carmel; West, Dee W; Andrulis, Irene L; Whittemore, Alice S; Hopper, John L
2011-10-01
A previous Australian population-based breast cancer case-control study found indirect evidence that control participation, although high, was not random. We hypothesized that unaffected sisters may provide a more appropriate comparison group than unrelated population controls. Three population-based case-control-family studies of breast cancer in women of white European origin were carried out by the Australian, Ontario and Northern California sites of the Breast Cancer Family Registry. We compared risk factors between 3643 cases, 2444 of their unaffected sisters and 2877 population controls and conducted separate case-control analyses based on population and sister controls using unconditional multivariable logistic regression. Compared with sister controls, population controls were more highly educated, had an earlier age at menarche, fewer births, their first birth at a later age and their last birth more recently. The established breast cancer associations detected using sister controls, but not detected using population controls, were decreasing risk with each of later age at menarche, more births, younger age at first birth and greater time since last birth. Since participation of population controls might be unintentionally related to some risk factors, we hypothesize that sister controls could provide more valid relative risk estimates and be recruited at lower cost. Given declining study participation by population controls, this contention is highly relevant to epidemiologic research.
ERIC Educational Resources Information Center
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…
Ecological feedbacks can reduce population-level efficacy of wildlife fertility control
Ransom, Jason I.; Powers, Jenny G.; Hobbs, N. Thompson; Baker, Dan L.
2014-01-01
1. Anthropogenic stress on natural systems, particularly the fragmentation of landscapes and the extirpation of predators from food webs, has intensified the need to regulate abundance of wildlife populations with management. Controlling population growth using fertility control has been considered for almost four decades, but nearly all research has focused on understanding effects of fertility control agents on individual animals. Questions about the efficacy of fertility control as a way to control populations remain largely unanswered. 2. Collateral consequences of contraception can produce unexpected changes in birth rates, survival, immigration and emigration that may reduce the effectiveness of regulating animal abundance. The magnitude and frequency of such effects vary with species-specific social and reproductive systems, as well as connectivity of populations. Developing models that incorporate static demographic parameters from populations not controlled by contraception may bias predictions of fertility control efficacy. 3. Many population-level studies demonstrate that changes in survival and immigration induced by fertility control can compensate for the reduction in births caused by contraception. The most successful cases of regulating populations using fertility control come from applications of contraceptives to small, closed populations of gregarious and easily accessed species. 4. Fertility control can result in artificial selection pressures on the population and may lead to long-term unintentional genetic consequences. The magnitude of such selection is dependent on individual heritability and behavioural traits, as well as environmental variation. 5. Synthesis and applications. Understanding species' life-history strategies, biology, behavioural ecology and ecological context is critical to developing realistic expectations of regulating populations using fertility control. Before time, effort and funding are invested in wildlife contraception, managers may need to consider the possibility that many species and populations can compensate for reduction in fecundity, and this could minimize any reduction in population growth rate.
Ecological feedbacks can reduce population-level efficacy of wildlife fertility control
Ransom, Jason I; Powers, Jenny G; Thompson Hobbs, N; Baker, Dan L
2014-01-01
Anthropogenic stress on natural systems, particularly the fragmentation of landscapes and the extirpation of predators from food webs, has intensified the need to regulate abundance of wildlife populations with management. Controlling population growth using fertility control has been considered for almost four decades, but nearly all research has focused on understanding effects of fertility control agents on individual animals. Questions about the efficacy of fertility control as a way to control populations remain largely unanswered. Collateral consequences of contraception can produce unexpected changes in birth rates, survival, immigration and emigration that may reduce the effectiveness of regulating animal abundance. The magnitude and frequency of such effects vary with species-specific social and reproductive systems, as well as connectivity of populations. Developing models that incorporate static demographic parameters from populations not controlled by contraception may bias predictions of fertility control efficacy. Many population-level studies demonstrate that changes in survival and immigration induced by fertility control can compensate for the reduction in births caused by contraception. The most successful cases of regulating populations using fertility control come from applications of contraceptives to small, closed populations of gregarious and easily accessed species. Fertility control can result in artificial selection pressures on the population and may lead to long-term unintentional genetic consequences. The magnitude of such selection is dependent on individual heritability and behavioural traits, as well as environmental variation. Synthesis and applications. Understanding species' life-history strategies, biology, behavioural ecology and ecological context is critical to developing realistic expectations of regulating populations using fertility control. Before time, effort and funding are invested in wildlife contraception, managers may need to consider the possibility that many species and populations can compensate for reduction in fecundity, and this could minimize any reduction in population growth rate. PMID:25558083
[Dynamic model of seasonal breeding rodent pest population controlled with short-acting sterilant].
Liu, Han-wu; Jin, Zhen; Zhang, Feng-qin; Li, Qiu-ying
2013-04-01
Rodent pests bring great damage to human beings, while rodenticide and sterilant can be used to control the pests. After ingesting sterilant, rodent pests lose their fertility, but in some cases, the sterile individuals may gain their fertility again, produce offspring, and enlarge population size. In this paper, the dynamic models of rodent pest population under lethal control and shortacting contraception control were formulated, and, with the prerequisite of the seasonal breeding of rodent pest population, the models were used to regularly analyze their behaviors and the effects of the contraception rate, lethal rate, control interval, and sterilant valid period on the dynamics of the pest population. The results showed that larger contraception rate and lethal rate and shorter control interval could have better control effect, making the controlled population become smaller and even died out. Short-acting sterilant limited the control effect. At the later period of breeding season, the rodent pest population controlled with short-acting sterilant would have a weak recovery.
Fedy, Bradley C.; O'Donnell, Michael; Bowen, Zachary H.
2015-01-01
Human impacts on wildlife populations are widespread and prolific and understanding wildlife responses to human impacts is a fundamental component of wildlife management. The first step to understanding wildlife responses is the documentation of changes in wildlife population parameters, such as population size. Meaningful assessment of population changes in potentially impacted sites requires the establishment of monitoring at similar, nonimpacted, control sites. However, it is often difficult to identify appropriate control sites in wildlife populations. We demonstrated use of Geographic Information System (GIS) data across large spatial scales to select biologically relevant control sites for population monitoring. Greater sage-grouse (Centrocercus urophasianus; hearafter, sage-grouse) are negatively affected by energy development, and monitoring of sage-grouse population within energy development areas is necessary to detect population-level responses. Weused population data (1995–2012) from an energy development area in Wyoming, USA, the Atlantic Rim Project Area (ARPA), and GIS data to identify control sites that were not impacted by energy development for population monitoring. Control sites were surrounded by similar habitat and were within similar climate areas to the ARPA. We developed nonlinear trend models for both the ARPA and control sites and compared long-term trends from the 2 areas. We found little difference between the ARPA and control sites trends over time. This research demonstrated an approach for control site selection across large landscapes and can be used as a template for similar impact-monitoring studies. It is important to note that identification of changes in population parameters between control and treatment sites is only the first step in understanding the mechanisms that underlie those changes. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
Integral control for population management.
Guiver, Chris; Logemann, Hartmut; Rebarber, Richard; Bill, Adam; Tenhumberg, Brigitte; Hodgson, Dave; Townley, Stuart
2015-04-01
We present a novel management methodology for restocking a declining population. The strategy uses integral control, a concept ubiquitous in control theory which has not been applied to population dynamics. Integral control is based on dynamic feedback-using measurements of the population to inform management strategies and is robust to model uncertainty, an important consideration for ecological models. We demonstrate from first principles why such an approach to population management is suitable via theory and examples.
Davis, Amy J.; Cunningham, Fred L.; VerCauteren, Kurt C.; Eckery, Doug C.
2017-01-01
Effective management of widespread invasive species such as wild pigs (Sus scrofa) is limited by resources available to devote to the effort. Better insight of the effectiveness of different management strategies on population dynamics is important for guiding decisions of resource allocation over space and time. Using a dynamic population model, we quantified effects of culling intensities and time between culling events on population dynamics of wild pigs in the USA using empirical culling patterns and data-based demographic parameters. In simulated populations closed to immigration, substantial population declines (50–100%) occurred within 4 years when 20–60% of the population was culled annually, but when immigration from surrounding areas occurred, there was a maximum of 50% reduction, even with the maximum culling intensity of 60%. Incorporating hypothetical levels of fertility control with realistic culling intensities was most effective in reducing populations when they were closed to immigration and when intrinsic population growth rate was too high (> = 1.78) to be controlled by culling alone. However, substantial benefits from fertility control used in conjunction with culling may only occur over a narrow range of net population growth rates (i.e., where net is the result of intrinsic growth rates and culling) that varies depending on intrinsic population growth rate. The management implications are that the decision to use fertility control in conjunction with culling should rely on concurrent consideration of achievable culling intensity, underlying demographic parameters, and costs of culling and fertility control. The addition of fertility control reduced abundance substantially more than culling alone, however the effects of fertility control were weaker than in populations without immigration. Because these populations were not being reduced substantially by culling alone, fertility control could be an especially helpful enhancement to culling for reducing abundance to target levels in areas where immigration can’t be prevented. PMID:28837610
Dinges, Andrew J.; Webb, Elisabeth B.; Vrtiska, Mark P.; Nilon, Charles H.; Wilhelm Stanis, Sonja A.
2014-01-01
We expanded the Nebraska Light Goose Conservation Order (LGCO) harvest survey (NE, USA) in spring 2012 to assess migratory bird hunter opinions regarding future management strategies for controlling light goose populations. Although hunters strongly agreed that population control of light geese was an important wildlife management issue, they were generally unsupportive of wildlife officials using forms of direct control methods to control light goose populations. Respondents who indicated participation in the 2012 LGCO were also less supportive of any form of direct control compared with migratory bird hunters who did not participate in the LGCO. When presented with alternative methods by wildlife officials for future light goose population control, respondents were most supportive of wildlife agencies selectively shooting light geese on migration and wintering areas and least supportive of wildlife officials using bait with approved chemicals to euthanize light geese. A clear understanding of public perception of various potential direct-control options will likely assist wildlife biologists in making informed decisions on how to proceed with population control of light geese.
Mina, Petros; Tsaneva-Atanasova, Krasimira; Bernardo, Mario di
2016-07-15
We extend a spatially explicit agent based model (ABM) developed previously to investigate entrainment and control of the emergent behavior of a population of synchronized oscillating cells in a microfluidic chamber. Unlike most of the work in models of control of cellular systems which focus on temporal changes, we model individual cells with spatial dependencies which may contribute to certain behavioral responses. We use the model to investigate the response of both open loop and closed loop strategies, such as proportional control (P-control), proportional-integral control (PI-control) and proportional-integral-derivative control (PID-control), to heterogeinities and growth in the cell population, variations of the control parameters and spatial effects such as diffusion in the spatially explicit setting of a microfluidic chamber setup. We show that, as expected from the theory of phase locking in dynamical systems, open loop control can only entrain the cell population in a subset of forcing periods, with a wide variety of dynamical behaviors obtained outside these regions of entrainment. Closed-loop control is shown instead to guarantee entrainment in a much wider region of control parameter space although presenting limitations when the population size increases over a certain threshold. In silico tracking experiments are also performed to validate the ability of classical control approaches to achieve other reference behaviors such as a desired constant output or a linearly varying one. All simulations are carried out in BSim, an advanced agent-based simulator of microbial population which is here extended ad hoc to include the effects of control strategies acting onto the population.
Phase control in coherent population distribution in molecules
NASA Astrophysics Data System (ADS)
Datta, Avijit
2018-06-01
A chirped laser pulse transfers population from one level to another level accessible by one photon dipole transition. We have used a pair of phase-locked chirped pulses of same frequency instead of a single chirped pulse to achieve phase control over the population transfer and thus creating coherent population distribution in hydrogen molecule. Simultaneous actions of the phase controlled interference and rapid adiabatic passages due to chirped pulses lead to the control in population transfer from the ground X(v = 0, j = 0) level to the C(v = 2, j = 1) level. We have extended this two-level system to a three-level 1 + 1 ladder system for population transfer from the X level to the J(v = 2, j = 2) level via the C intermediate level using two pairs of phase-locked laser chirped pulses and have achieved laudable control over the coherent population distribution.
Using population genetic tools to develop a control strategy for feral cats (Felis catus) in Hawai'i
Hansen, H.; Hess, S.C.; Cole, D.; Banko, P.C.
2007-01-01
Population genetics can provide information about the demographics and dynamics of invasive species that is beneficial for developing effective control strategies. We studied the population genetics of feral cats on Hawai'i Island by microsatellite analysis to evaluate genetic diversity and population structure, assess gene flow and connectivity among three populations, identify potential source populations, characterise population dynamics, and evaluate sex-biased dispersal. High genetic diversity, low structure, and high number of migrants per generation supported high gene flow that was not limited spatially. Migration rates revealed that most migration occurred out of West Mauna Kea. Effective population size estimates indicated increasing cat populations despite control efforts. Despite high gene flow, relatedness estimates declined significantly with increased geographic distance and Bayesian assignment tests revealed the presence of three population clusters. Genetic structure and relatedness estimates indicated male-biased dispersal, primarily from Mauna Kea, suggesting that this population should be targeted for control. However, recolonisation seems likely, given the great dispersal ability that may not be inhibited by barriers such as lava flows. Genetic monitoring will be necessary to assess the effectiveness of future control efforts. Management of other invasive species may benefit by employing these population genetic tools. ?? CSIRO 2007.
Chen, Cheng; Xun, Pengcheng; Nishijo, Muneko; Carter, Sue; He, Ka
2016-01-01
We aimed to evaluate the association of cadmium exposure with the risk of prostate cancer in both the general and occupational populations. Online database searches were performed for studies of prostate cancer risk and cadmium exposure. Twelve cohort studies (5 in the general, 7 in occupational populations) and 9 case-control studies (3 in the general, 6 in occupational populations) were identified. Five/seven cohort studies in the general and occupational populations consist of 78,263/13, 434 participants with a mean follow-up of 12.1/43.0 years, respectively. Case-control studies include 334 cases/670 controls in the general population, and 1,315 cases/4,477 controls in occupational populations. Comparing the highest to the lowest category of cadmium exposure in the general population, the weighted relative risk of prostate cancer incidence and mortality among cohort studies, and the weighted odds ratio in case-control studies were 1.05 (95%CI [0.91, 1.22]), 0.83 (95%CI [0.35, 1.98]), and 1.27 (95%CI [0.58,2.78]), respectively. For occupational populations, the weighted OR in case-control studies was 1.17 (95%CI [0.85, 1.62]), and the weighted standardized mortality ratio in cohort studies was 98 (95%CI [75, 126]). Accumulated epidemiological evidence does not support the hypothesis that cadmium exposure may increase the risk of prostate cancer in either the general or occupational populations. PMID:27174617
Chen, Cheng; Xun, Pengcheng; Nishijo, Muneko; Carter, Sue; He, Ka
2016-05-13
We aimed to evaluate the association of cadmium exposure with the risk of prostate cancer in both the general and occupational populations. Online database searches were performed for studies of prostate cancer risk and cadmium exposure. Twelve cohort studies (5 in the general, 7 in occupational populations) and 9 case-control studies (3 in the general, 6 in occupational populations) were identified. Five/seven cohort studies in the general and occupational populations consist of 78,263/13, 434 participants with a mean follow-up of 12.1/43.0 years, respectively. Case-control studies include 334 cases/670 controls in the general population, and 1,315 cases/4,477 controls in occupational populations. Comparing the highest to the lowest category of cadmium exposure in the general population, the weighted relative risk of prostate cancer incidence and mortality among cohort studies, and the weighted odds ratio in case-control studies were 1.05 (95%CI [0.91, 1.22]), 0.83 (95%CI [0.35, 1.98]), and 1.27 (95%CI [0.58,2.78]), respectively. For occupational populations, the weighted OR in case-control studies was 1.17 (95%CI [0.85, 1.62]), and the weighted standardized mortality ratio in cohort studies was 98 (95%CI [75, 126]). Accumulated epidemiological evidence does not support the hypothesis that cadmium exposure may increase the risk of prostate cancer in either the general or occupational populations.
The role of self-defined race/ethnicity in population structure control.
Liu, X-Q; Paterson, A D; John, E M; Knight, J A
2006-07-01
Population-based association studies are powerful tools for the genetic mapping of complex diseases. However, this method is sensitive to potential confounding by population structure. While statistical methods that use genetic markers to detect and control for population structure have been the focus of current literature, the utility of self-defined race/ethnicity in controlling for population structure has been controversial. In this study of 1334 individuals, who self-identified as either African American, European American or Hispanic, we demonstrated that when the true underlying genetic structure and the self-defined racial/ethnic groups were roughly in agreement with each other, the self-defined race/ethnicity information was useful in the control of population structure.
Li, Lin; Zhang, Min; Holman, C D'Arcy J
2013-01-01
To assess dietary isoflavone intake between population and hospital outpatient controls and examine if cancer risks estimated for isoflavone using hospital outpatient controls would be different from those using population controls. Three parallel case-control studies on leukemia, breast, and colorectal cancers in China in 2009-2010 were conducted, using population and hospital outpatient controls to separately match 560 incident cases at a 1:1 ratio. A validated food frequency questionnaire was administered by face-to-face interview. Conditional logistic regression analysis was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). The 2 control groups had closely similar distributions of dietary isoflavone intake. Risk estimates for breast cancers were adjusted ORs (95% CI) of 0.39 (0.23-0.66) and 0.31 (0.18-0.55) for daidzein, 0.35 (0.20-0.61) and 0.28 (0.16-0.52) for genistein, 0.66 (0.41-1.08) and 0.53 (0.32-0.88) for glycitein, and 0.53 (0.33-0.85) and 0.43 (0.26-0.71) for total isoflavone using hospital outpatient and population controls respectively. The study found that hospital outpatient controls were comparable to population controls in measured dietary intake of isoflavone in the Chinese hospital setting.
Robust set-point regulation for ecological models with multiple management goals.
Guiver, Chris; Mueller, Markus; Hodgson, Dave; Townley, Stuart
2016-05-01
Population managers will often have to deal with problems of meeting multiple goals, for example, keeping at specific levels both the total population and population abundances in given stage-classes of a stratified population. In control engineering, such set-point regulation problems are commonly tackled using multi-input, multi-output proportional and integral (PI) feedback controllers. Building on our recent results for population management with single goals, we develop a PI control approach in a context of multi-objective population management. We show that robust set-point regulation is achieved by using a modified PI controller with saturation and anti-windup elements, both described in the paper, and illustrate the theory with examples. Our results apply more generally to linear control systems with positive state variables, including a class of infinite-dimensional systems, and thus have broader appeal.
Order of events matter: comparing discrete models for optimal control of species augmentation.
Bodine, Erin N; Gross, Louis J; Lenhart, Suzanne
2012-01-01
We investigate optimal timing of augmentation of an endangered/threatened species population in a target region by moving individuals from a reserve or captive population. This is formulated as a discrete-time optimal control problem in which augmentation occurs once per time period over a fixed number of time periods. The population model assumes the Allee effect growth functions in both target and reserve populations and the control objective is to maximize the target and reserve population sizes over the time horizon while accounting for costs of augmentation. Two possible orders of events are considered for different life histories of the species relative to augmentation time: move individuals either before or after population growth occurs. The control variable is the proportion of the reserve population to be moved to the target population. We develop solutions and illustrate numerical results which indicate circumstances for which optimal augmentation strategies depend upon the order of events.
Birth control, population control, and family planning: an overview.
Critchlow, D T
1995-01-01
This overview of the US birth control movement reflects on the emergence of family planning policy due to the efforts of Margaret Sanger, feminists, and the civil rights movement, the eugenics motive to limit "deviant" populations, and the population control movement, which aims to solve social and economic problems through fertility control. Population control moved through three stages: from the cause of "voluntary motherhood" to advance suffrage and women's political and social status, to the concept of "birth control" promoted by socialist feminists to help empower women and the working class, to, from 1920 on, a liberal movement for civil rights and population control. Physicians such as Dr. Robert Latou Dickinson legitimized the movement in the formation of the Committee on Maternal Health in 1925, but the movement remained divided until 1939, when Sanger's group merged with the American Birth Control League, the predecessor of the present Planned Parenthood Federation of America. A key legal decision in 1939 in the United States v. One Package amended the Comstock Act and allowed for the distribution of birth control devices by mail to physicians. Sanger, after a brief retirement, formed the International Planned Parenthood Federation and supported research into the pill. Eugenicists through the Committee on Maternal Health supported Christopher Tietze and others developing the pill. Final constitutional access to contraception based on the right to privacy was granted in Griswold v. Connecticut. The ruling in Eisenstadt v. Baird in 1972 extended this right to unmarried persons. The right to privacy was further extended in the Roe v. Wade decision in 1973 on legal abortion. The argument for improving the quality of the population remained from the formation of the Population Reference Bureau in 1929 through the 1960s. Under the leadership of Rockefeller, population control was defined as justified on a scientific and humanitarian basis. US government support for national and international family planning proceeded slowly through the 1950s, 1960s, and 1970s. Congress during 1967-70 enacted strong legislation in support of national and international family planning. The Bucharest conference in 1974 highlighted the inadequacies of international population control that deemphasized economic development. Polarization and divisiveness on population policy persists.
Ong, Song-Quan; Ahmad, Hamdan; Jaal, Zairi; Rus, Adanan; Fadzlah, Fadhlina Hazwani Mohd
2017-01-01
Determining the control threshold for a pest is common prior to initiating a pest control program; however, previous studies related to the house fly control threshold for a poultry farm are insufficient for determining such a threshold. This study aimed to predict the population changes of house fly population by comparing the intrinsic rate of increase (r m ) for different house fly densities in a simulated system. This study first defined the knee points of a known population growth curve as a control threshold by comparing the r m of five densities of house flies in a simulated condition. Later, to understand the interactions between the larval and adult populations, the correlation between larval and adult capacity rate (r c ) was studied. The r m values of 300- and 500-fly densities were significantly higher compared with the r m values at densities of 50 and 100 flies. This result indicated their representative indices as candidates for a control threshold. The r c of larval and adult populations were negatively correlated with densities of fewer than 300 flies; this implicated adult populations with fewer than 300 flies as declining while the larval population was growing; therefore, control approaches should focus on the immature stages. The results in the present study suggest a control threshold for house fly populations. Future works should focus on calibrating the threshold indices in field conditions. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Coleman, J D; Coleman, M C; Warburton, B
2006-04-01
To determine the trap-catch index (an estimate of abundance) of brushtail possum (Trichosurus vulpecula) populations infected with bovine tuberculosis (Tb; Mycobacterium bovis) that must be achieved, and the length of time such an index must be maintained, for Tb to be eliminated from possum populations and adjacent livestock. Between 1997-1998 and 2000-2001, trap-catch surveys of possum populations naturally infected with Tb and subjected to population-control measures were undertaken at four forest sites and two farmland sites. At the same time, possum carcasses were collected at these sites and their Tb status determined, and all contiguous cattle and deer herds were Tb tested and abattoir slaughter data for these herds were interrogated. Trap-catch surveys indicated that numbers of possums on the farmland sites surveyed were usually very low and well below the control targets set (i.e. a 5% trap catch or approximately 0.5-1 possum/ha) for the study. In contrast, trap-catch surveys undertaken in forest sites indicated possum numbers were more variable, and often recovered rapidly from control operations to exceed control targets within 1-3 years. The annual rate of recovery of possum populations in half of the forest population surveys undertaken exceeded published intrinsic rates of increase for possums. The overall prevalence of Tb in possum populations was < or =1.9% at 5/6 sites, and was 6.5% at the sixth site. Juvenile possums infected with Tb were trapped within but near the edge of control zones and appeared to represent an immigrant source of infection. Mature infected possums survived control operations apparently by having home ranges in uncontrolled patches within control areas. Infection in possums appeared to be eliminated from one study site by the intensive control undertaken, but elimination at other sites appeared less likely. Levels of Tb in livestock on or adjacent to the study sites fell by at least 50% during the study, and cattle in one area tested clear for the first time in 20 years. Initial control of possums in forest appeared to achieve national control targets set by the Animal Health Board (AHB), despite trap-catch data often providing misleading population estimates. Such targets were often exceeded within 1-3 years. By comparison, possum control on farmland appeared to maintain populations at very low levels, while control on forest margins maintained populations at intermediate levels. Control was least effective in deep forest where human access was most difficult. Intensive population control measures appeared to have led to a reduced incidence of Tb in livestock at 3/4 sites, and elimination of Tb in livestock at one site. This result supports modelling studies that predict the eradication of Tb from possums through ongoing intensive control and may explain the lower success achieved with earlier less-intensive possum control.
Passive Baited Sequential Fly Trap
USDA-ARS?s Scientific Manuscript database
Sampling fly populations associated with human populations is needed to understand diel behavior and to monitor population densities before and after control operations. Population control measures are dependent on the results of monitoring efforts as they may provide insight into the fly behavior ...
An integral projection model with YY-males and application to evaluating grass carp control
Erickson, Richard A.; Eager, Eric A.; Brey, Marybeth; Hansen, Michael J.; Kocovsky, Patrick
2017-01-01
Invasive fish species disrupt ecosystems and cause economic damage. Several methods have been discussed to control populations of invasive fish including the release of YY-males. YY-males are fish that have 2 male chromosomes compared to a XY-male. When YY-males mate, they only produce male (XY) offspring. This decreases the female proportion of the population and can, in theory, eradicate local populations by biasing the sex-ratio. YY-males have been used as a population control tool for brook trout in montane streams and lakes in Idaho, USA. The YY-male control method has been discussed for grass carp in Lake Erie, North America. We developed and presented an integral projection model for grass carp to model the use of YY-males as a control method for populations in this lake. Using only the YY-male control method, we found that high levels of YY-males would need to be release annually to control the species. Specifically, these levels were the same order of magnitude as the baseline adult population (e.g., 1000 YY-males needed to be released annual for 20 years to control a baseline adult population of 2500 grass carp). These levels may not be reasonable or obtainable for fisheries managers given the impacts of YY-males on aquatic vegetation and other constraints of natural resource management.
Population control in symbiotic corals
DOE Office of Scientific and Technical Information (OSTI.GOV)
Falkowski, P.G.; Dubinsky, Z.; Muscatine, L.
1993-10-01
Stability in symbiotic association requires control of population growth between symbionts. The population density of zooxanthellae per unit surface area of most symbiotic corals is remarkably consistant. How is the population density of zooxanthellae maintained and what happens to the symbiotic association if the balance between algae and host is perturbed. The answers to these question, examined in this paper, provide a framework for understanding how the size of the component populations is controlled in symbiotic associations. The topic areas covered include the following: carbon economy in a symbiotic coral; effects of nutrient enrichment; the chemostat model of population control;more » the effects of exposure to ammonium levels. Ammonium ions and organic materials are the factors which maintain the density of zooxanthellae. 32 refs., 5 figs.« less
Small mammal populations at hazardous waste disposal sites near Houston, Texas, USA
Robbins, C.S.
1990-01-01
Small mammals were trapped, tagged and recaptured in 0?45 ha plots at six hazardous industrial waste disposal sites to determine if populations, body mass and age structures were different from paired control site plots. Low numbers of six species of small mammals were captured on industrial waste sites or control sites. Only populations of hispid cotton rats at industrial waste sites and control sites were large enough for comparisons. Overall population numbers, age structure, and body mass of adult male and female cotton rats were similar at industrial waste sites and control sites. Populations of small mammals (particularly hispid cotton rats) may not suffice as indicators of environments with hazardous industrial waste contamination.
Differences between blood donors and a population sample: implications for case-control studies.
Golding, Jean; Northstone, Kate; Miller, Laura L; Davey Smith, George; Pembrey, Marcus
2013-08-01
Selecting appropriate controls for studies of genetic variation in case series is important. The two major candidates involve the use of blood donors or a random sample of the population. We compare and contrast the two different populations of controls for studies of genetic variation using data from parents enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC). In addition we compute different biases using a series of hypothetical assumptions. The study subjects who had been blood donors differed markedly from the general population in social, health-related, anthropometric, and personality-related variables. Using theoretical examples, we show that blood donors are a poor control group for non-genetic studies of diseases related to environmentally, behaviourally, or socially patterned exposures. However, we show that if blood donors are used as controls in genetic studies, these factors are unlikely to make a major difference in detecting true associations with relatively rare disorders (cumulative incidence through life of <10%). Nevertheless, for more common disorders, the reduction in accuracy resulting from the inclusion in any control population of individuals who have or will develop the disease in question can create a greater bias than can socially patterned factors. Information about the medical history of a control and the parents of the control (as a proxy for whether the control will develop the disease) is more important with regard to the choice of controls than whether the controls are a random population sample or blood donors.
McCarthy, Robert J; Levine, Stephen H; Reed, J Michael
2013-08-15
To predict effectiveness of 3 interventional methods of population control for feral cat colonies. Population model. Estimates of vital data for feral cats. Data were gathered from the literature regarding the demography and mating behavior of feral cats. An individual-based stochastic simulation model was developed to evaluate the effectiveness of trap-neuter-release (TNR), lethal control, and trap-vasectomy-hysterectomy-release (TVHR) in decreasing the size of feral cat populations. TVHR outperformed both TNR and lethal control at all annual capture probabilities between 10% and 90%. Unless > 57% of cats were captured and neutered annually by TNR or removed by lethal control, there was minimal effect on population size. In contrast, with an annual capture rate of ≥ 35%, TVHR caused population size to decrease. An annual capture rate of 57% eliminated the modeled population in 4,000 days by use of TVHR, whereas > 82% was required for both TNR and lethal control. When the effect of fraction of adult cats neutered on kitten and young juvenile survival rate was included in the analysis, TNR performed progressively worse and could be counterproductive, such that population size increased, compared with no intervention at all. TVHR should be preferred over TNR for management of feral cats if decrease in population size is the goal. This model allowed for many factors related to the trapping program and cats to be varied and should be useful for determining the financial and person-effort commitments required to have a desired effect on a given feral cat population.
Tuberculosis in vulnerable populations in Eastern Mediterranean Region-Implications for control.
Shakoor, Sadia; Hasan, Rumina
2016-12-01
Socially and economically disadvantaged or "vulnerable" people are at high risk of tuberculosis (TB) and also contribute to active chains of TB transmission. Included in such vulnerable populations are children, women, prisoners, people living with human immunodeficiency virus, the homeless, and displaced people. The ongoing active transmission of TB among such populations is made more difficult to assess and control by difficult access, health inequities, poverty, and other chronic and debilitating health conditions at individual, domestic, and community levels. The 22 Eastern Mediterranean Region member states encompass diverse sociopolitical and socioeconomic situations with far-reaching effects on vulnerable populations in each country, thereby threatening the control of TB. Here, we examined the impact of these populations on the incidence and transmission of TB in light of these risks. Approximately 60% of the regional population comprises children and adolescents ⩽19years of age, increasing the population at risk. Additionally, up to 11% of the population suffers from mental- or substance-abuse disorders, while >50% of the world refugee populations live in the Eastern Mediterranean Region. TB control requires a strategic approach at the country level to access these vulnerable populations. Copyright © 2016.
Feedback quantum control of molecular electronic population transfer
NASA Astrophysics Data System (ADS)
Bardeen, Christopher J.; Yakovlev, Vladislav V.; Wilson, Kent R.; Carpenter, Scott D.; Weber, Peter M.; Warren, Warren S.
1997-11-01
Feedback quantum control, where the sample `teaches' a computer-controlled arbitrary lightform generator to find the optimal light field, is experimentally demonstrated for a molecular system. Femtosecond pulses tailored by a computer-controlled acousto-optic pulse shaper excite fluorescence from laser dye molecules in solution. Fluorescence and laser power are monitored, and the computer uses the experimental data and a genetic algorithm to optimize population transfer from ground to first excited state. Both efficiency (the ratio of excited state population to laser energy) and effectiveness (total excited state population) are optimized. Potential use as an `automated theory tester' is discussed.
Paul, Christine Louise; Bonevski, Billie; Turon, Heidi Erin; Bryant, Jamie
2012-07-01
Despite the persistent socioeconomic gradient associated with smoking, little is known about how to 'close the gap'. There is a debate regarding the implications of directing resources away from general population efforts towards disadvantaged groups. The study explored views of those with expertise in tobacco control about the appropriate balance of tobacco control resourcing between the general population and disadvantaged groups. A Web-based survey of 192 respondents (response rate 65%) working in tobacco control in Australia and New Zealand was completed. Respondents were sampled from the Australian and New Zealand Tobacco Control Contact List and a literature search. Respondents were asked to allocate a hypothetical budget for: (a) anti-tobacco mass media campaigns; and (b) tobacco control research. The vast majority (93%) of respondents believed that some tobacco control resources should be specifically directed towards disadvantaged groups. Respondents believed up to half of mass media resources should be directed towards disadvantaged groups. In the case of tobacco control research, the median allocation to the general population was approximately one-third of a hypothetical research budget. It appears there is a desire among the Australian and New Zealand tobacco control community for substantial effort to be directed towards disadvantaged groups. It is important to develop an evidence base to ensure an efficient and equitable approach to balancing the potentially competing demands of general population versus disadvantaged group activities in relation to tobacco control. © 2012 Australasian Professional Society on Alcohol and other Drugs.
Castaño-Vinyals, Gemma; Nieuwenhuijsen, Mark J; Moreno, Víctor; Carrasco, Estela; Guinó, Elisabet; Kogevinas, Manolis; Villanueva, Cristina M
2011-01-01
Low participation rates in the selection of population controls are an increasing concern for the validity of case-control studies worldwide. We conducted a pilot study to assess two approaches to recruiting population controls in a study of colorectal cancer, including a face-to-face interview and blood sample collection. In the first approach, persons identified through a population roster were invited to participate through a telephone call by an interviewer telephoning on behalf of our research center. In the second approach, individuals were identified from the lists of selected family practitioners and were telephoned on behalf of the family practitioner. When the second method was used, participation rates increased from 42% to 57% and the percentage of refusals decreased from 47% to 13%. The reasons for refusing to participate did not differ significantly between the two methods. Contact through the family practitioner yielded higher response rates in population controls in the study area. 2010 SESPAS. Published by Elsevier Espana. All rights reserved.
21 CFR 522.1289 - Lufenuron suspension.
Code of Federal Regulations, 2011 CFR
2011-04-01
... control of flea populations. Lufenuron controls flea populations by preventing the development of flea... control of adult fleas. (iii) Limitations. For subcutaneous use in cats only. The safety of this product...
21 CFR 522.1289 - Lufenuron suspension.
Code of Federal Regulations, 2013 CFR
2013-04-01
... control of flea populations. Lufenuron controls flea populations by preventing the development of flea... control of adult fleas. (iii) Limitations. For subcutaneous use in cats only. The safety of this product...
21 CFR 522.1289 - Lufenuron suspension.
Code of Federal Regulations, 2012 CFR
2012-04-01
... control of flea populations. Lufenuron controls flea populations by preventing the development of flea... control of adult fleas. (iii) Limitations. For subcutaneous use in cats only. The safety of this product...
49 CFR 372.243 - Controlling distances and population data.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 5 2012-10-01 2012-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be the...
49 CFR 372.243 - Controlling distances and population data.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 5 2014-10-01 2014-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be the...
49 CFR 372.243 - Controlling distances and population data.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 5 2013-10-01 2013-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be the...
49 CFR 372.243 - Controlling distances and population data.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 5 2010-10-01 2010-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be the...
49 CFR 372.243 - Controlling distances and population data.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 5 2011-10-01 2011-10-01 false Controlling distances and population data. 372.243... population data. In the application of § 372.241: (a) Air-line distances or mileages about corporate limits of municipalities shall be used. (b) The population of any municipality shall be deemed to be the...
Berg, Annika
2010-09-01
This article delineates a strong continuity, particularly in terms of personnel, between interwar domestic population policies and Sweden's postwar participation in international and transnational population-control programs. It argues that Swedish engagement in population control and family planning in the emerging Third World, and particularly in South Asia, was motivated by the conviction that poverty and underdevelopment must be attacked on several fronts simultaneously, with population control being one of the most important. In its first bilateral aid programs Sweden would prioritize the promotion of birth control primarily because it was still too controversial to be promoted multilaterally, not least for religious reasons; and because Swedish experts were regarded as especially liberal, rational, and secularized. Sterilization expertise played no decisive part in this continuity. When first establishing themselves in South Asia, Swedish experts would recommend the rhythm method and other contraceptive methods that depended on self-control.
Group selections among laboratory populations of Tribolium.
Wade, M J
1976-12-01
Selection at the population level or group selection is defined as genetic change that is brought about or maintained by the differential extinction and/or proliferation of populations. Group selection for both increased and decreased adult population size was carried out among laboratory populations of Tribolium castaneum at 37-day intervals. The effect of individual selection within populations on adult population size was evaluated in an additional control series of populations. The response in the group selection treatments occurred rapidly, within three or four generations, and was large in magnitude, at times differing from the controls by over 200%. This response to selection at the populational level occurred despite strong individual selection which caused a decline in the mean size of the control populations from over 200 adults to near 50 adults in nine 37-day intervals. "Assay" experiments indicated that selective changes in fecundity, developmental time, body weight, and cannibalism rates were responsible in part for the observed treatment differences in adult population size. These findings have implications in terms of speciation in organisms whose range is composed of many partially isolated local populations.
The evolution and devolution of cognitive control: The costs of deliberation in a competitive world
Tomlin, Damon; Rand, David G.; Ludvig, Elliot A.; Cohen, Jonathan D.
2015-01-01
Dual-system theories of human cognition, under which fast automatic processes can complement or compete with slower deliberative processes, have not typically been incorporated into larger scale population models used in evolutionary biology, macroeconomics, or sociology. However, doing so may reveal important phenomena at the population level. Here, we introduce a novel model of the evolution of dual-system agents using a resource-consumption paradigm. By simulating agents with the capacity for both automatic and controlled processing, we illustrate how controlled processing may not always be selected over rigid, but rapid, automatic processing. Furthermore, even when controlled processing is advantageous, frequency-dependent effects may exist whereby the spread of control within the population undermines this advantage. As a result, the level of controlled processing in the population can oscillate persistently, or even go extinct in the long run. Our model illustrates how dual-system psychology can be incorporated into population-level evolutionary models, and how such a framework can be used to examine the dynamics of interaction between automatic and controlled processing that transpire over an evolutionary time scale. PMID:26078086
The evolution and devolution of cognitive control: The costs of deliberation in a competitive world.
Tomlin, Damon; Rand, David G; Ludvig, Elliot A; Cohen, Jonathan D
2015-06-16
Dual-system theories of human cognition, under which fast automatic processes can complement or compete with slower deliberative processes, have not typically been incorporated into larger scale population models used in evolutionary biology, macroeconomics, or sociology. However, doing so may reveal important phenomena at the population level. Here, we introduce a novel model of the evolution of dual-system agents using a resource-consumption paradigm. By simulating agents with the capacity for both automatic and controlled processing, we illustrate how controlled processing may not always be selected over rigid, but rapid, automatic processing. Furthermore, even when controlled processing is advantageous, frequency-dependent effects may exist whereby the spread of control within the population undermines this advantage. As a result, the level of controlled processing in the population can oscillate persistently, or even go extinct in the long run. Our model illustrates how dual-system psychology can be incorporated into population-level evolutionary models, and how such a framework can be used to examine the dynamics of interaction between automatic and controlled processing that transpire over an evolutionary time scale.
Crampin, A C; Mwinuka, V; Malema, S S; Glynn, J R; Fine, P E
2001-01-01
Selection bias, particularly of controls, is common in case-control studies and may materially affect the results. Methods of control selection should be tailored both for the risk factors and disease under investigation and for the population being studied. We present here a control selection method devised for a case-control study of tuberculosis in rural Africa (Karonga, northern Malawi) that selects an age/sex frequency-matched random sample of the population, with a geographical distribution in proportion to the population density. We also present an audit of the selection process, and discuss the potential of this method in other settings.
The biology of small, introduced populations, with special reference to biological control
Fauvergue, Xavier; Vercken, Elodie; Malausa, Thibaut; Hufbauer, Ruth A
2012-01-01
Populations are introduced into novel environments in different contexts, one being the biological control of pests. Despite intense efforts, less than half introduced biological control agents establish. Among the possible approaches to improve biological control, one is to better understand the processes that underpin introductions and contribute to ecological and evolutionary success. In this perspective, we first review the demographic and genetic processes at play in small populations, be they stochastic or deterministic. We discuss the theoretical outcomes of these different processes with respect to individual fitness, population growth rate, and establishment probability. Predicted outcomes differ subtly in some cases, but enough so that the evaluating results of introductions have the potential to reveal which processes play important roles in introduced populations. Second, we attempt to link the theory we have discussed with empirical data from biological control introductions. A main result is that there are few available data, but we nonetheless report on an increasing number of well-designed, theory-driven, experimental approaches. Combining demography and genetics from both theoretical and empirical perspectives highlights novel and exciting avenues for research on the biology of small, introduced populations, and great potential for improving both our understanding and practice of biological control. PMID:22949919
Beaty, Lynne E; Salice, Christopher J
2013-10-01
Invasive species are costly and difficult to control. In order to gain a mechanistic understanding of potential control measures, individual-based models uniquely parameterized to reflect the salient life-history characteristics of invasive species are useful. Using invasive Australian Rhinella marina as a case study, we constructed a cohort- and individual-based population simulation that incorporates growth and body size of terrestrial stages. We used this allometric approach to examine the efficacy of nontraditional control methods (i.e., tadpole alarm chemicals and native meat ants) that may have indirect effects on population dynamics mediated by effects on body size. We compared population estimates resulting from these control methods with traditional hand removal. We also conducted a sensitivity analysis to investigate the effect that model parameters, specifically those associated with growth and body size, had on adult population estimates. Incremental increases in hand removal of adults and juveniles caused nonlinear decreases in adult population estimates, suggesting less return with increased investment in hand-removal efforts. Applying tadpole alarm chemicals or meat ants decreased adult population estimates on the same level as removing 15-25% of adults and juveniles by hand. The combined application of tadpole alarm chemicals and meat ants resulted in approximately 80% decrease in adult abundance, the largest of any applied control method. In further support of the nontraditional control methods, which greatly affected the metamorph stage, our model was most sensitive to changes in metamorph survival, juvenile survival, metamorph growth rate, and adult survival. Our results highlight the use and insights that can be gained from individual-based models that incorporate growth and body size and the potential success that nontraditional control methods could have in controlling established, invasive Rhinella marina populations.
Biological control via "ecological" damping: An approach that attenuates non-target effects.
Parshad, Rana D; Quansah, Emmanuel; Black, Kelly; Beauregard, Matthew
2016-03-01
In this work we develop and analyze a mathematical model of biological control to prevent or attenuate the explosive increase of an invasive species population, that functions as a top predator, in a three-species food chain. We allow for finite time blow-up in the model as a mathematical construct to mimic the explosive increase in population, enabling the species to reach "disastrous", and uncontrollable population levels, in a finite time. We next improve the mathematical model and incorporate controls that are shown to drive down the invasive population growth and, in certain cases, eliminate blow-up. Hence, the population does not reach an uncontrollable level. The controls avoid chemical treatments and/or natural enemy introduction, thus eliminating various non-target effects associated with such classical methods. We refer to these new controls as "ecological damping", as their inclusion dampens the invasive species population growth. Further, we improve prior results on the regularity and Turing instability of the three-species model that were derived in Parshad et al. (2014). Lastly, we confirm the existence of spatiotemporal chaos. Copyright © 2016 Elsevier Inc. All rights reserved.
Hirsbrunner, G; Knutti, B; Eicher, R
1999-01-01
In a retrospective study, we compared the abortion rates of 59 cows in the second half of gestation, admitted to the Clinic for Food Animals and Horses (1993-1996) with a strictly focal problem (head region, udder and teats, locomotor system) requiring surgery in lateral recumbency, to the abortion rate of a control cow population. Before surgery, a uterus relaxant was given in 42 cases, and 17 cows were untreated as to pregnancy. Cows included in the reproduction health program of the Department of Fertility and Reproduction were used as a control population. Data of 1,736 cows pregnant in the second half of gestation per year were available for the same time period (1993-1996). Abortion rate was 5.08% for the cows undergoing surgery in lateral recumbency as compared with 5.18% for the cows of the control population. There was no significant difference between the two populations (P > 0.05). Thus, the risk for abortion in the cows in question is not elevated as compared with the control population.
Dalager-Pedersen, Michael; Koch, Kristoffer; Thomsen, Reimar Wernich; Schønheyder, Henrik Carl; Nielsen, Henrik
2014-01-29
Little is known about the prognosis of community-acquired bacteraemia (CAB) in workforce adults. We assessed return to workforce, risk for sick leave, disability pension and mortality within 1 year after CAB in workforce adults compared with blood culture-negative controls and population controls. Population-based cohort study. North Denmark, 1996-2011. We used population-based healthcare registries to identify all patients aged 20-58 years who had first-time blood cultures obtained within 48 h of medical hospital admission, and who were part of the workforce (450 bacteraemia exposed patients and 6936 culture-negative control patients). For each bacteraemia patient, we included up to 10 matched population controls. Return to workforce, risk of sick leave, permanent disability pension and mortality within 1 year after bacteraemia. Regression analyses were used to compute adjusted relative risks (RRs) with 95% CIs. One year after admission, 78% of patients with CAB, 85.7% of culture-negative controls and 96.8% of population controls were alive and in the workforce, and free from sick leave or disability pension. Compared with culture-negative controls, bacteraemia was associated with an increased risk for long-term sick leave (4-week duration, 40.2% vs 23.9%, adjusted RR, 1.51; CI 1.34 to 1.70) and an increased risk for mortality (30-day mortality, 4% vs 1.4%, adjusted RR, 2.34, CI 1.22 to 4.50; 1-year mortality, 8% vs 3.9%, adjusted RR, 1.73; CI 1.18 to 2.55). Bacteraemia patients had a risk for disability pension similar to culture-negative controls (2.7% vs 2.6%, adjusted RR, 0.99, CI 0.48 to 2.02) but greater than population controls (adjusted RR, 5.20; 95% CI 2.16 to 12.50). CAB is associated with long duration of sick leave and considerable mortality in working-age adults when compared with blood culture-negative controls, and an increased 1-year risk for disability pension when compared with population controls.
Hixson, Mark; Mahmud, Abdullah; Hu, Jianlin; Kleeman, Michael J
2012-05-01
The effectiveness of emissions control programs designed to reduce concentrations of airborne particulate matter with an aerodynamic diameter < 2.5 microm (PM2.5) in California's San Joaquin Valley was studied in the year 2030 under three growth scenarios: low, medium, and high population density. Base-case inventories for each choice of population density were created using a coupled emissions modeling system that simultaneously considered interactions between land use and transportation, area source, and point source emissions. The ambient PM2.5 response to each combination of population density and emissions control was evaluated using a regional chemical transport model over a 3-week winter stagnation episode. Comparisons between scenarios were based on regional average and population-weighted PM2.5 concentrations. In the absence of any emissions control program, population-weighted concentrations of PM2.5 in the future San Joaquin Valley are lowest undergrowth scenarios that emphasize low population density. A complete ban on wood burning and a 90% reduction in emissions from food cooking operations and diesel engines must occur before medium- to high-density growth scenarios result in lower population-weighted concentrations of PM2.5. These trends partly reflect the fact that existing downtown urban cores that naturally act as anchor points for new high-density growth in the San Joaquin Valley are located close to major transportation corridors for goods movement. Adding growth buffers around transportation corridors had little impact in the current analysis, since the 8-km resolution of the chemical transport model already provided an artificial buffer around major emissions sources. Assuming that future emissions controls will greatly reduce or eliminate emissions from residential wood burning, food cooking, and diesel engines, the 2030 growth scenario using "as-planned" (medium) population density achieves the lowest population-weighted average PM2.5 concentration in the future San Joaquin Valley during a severe winter stagnation event. The San Joaquin Valley is one of the most heavily polluted air basins in the United States that are projected to experience strong population growth in the coming decades. The best plan to improve air quality in the region combines medium- or high-density population growth with rigorous emissions controls. In the absences of controls, high-density growth leads to increased population exposure to PM2.5 compared with low-density growth scenarios (urban sprawl).
Estimation of Critical Population Support Requirements.
1984-05-30
VA 22160 W.U. 4921H 11. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE Federal Emergency Management Agency May 30, 1984 Industrial Protection...ensure the availability of industrial production required to support the population, maintain defense capabilities and perform command and control ...the population, maintain national defense capabilities and perform command and control activi- ties during a national emergency such as a threat of a
Methods Needed to Curb Rising Pet Population
ERIC Educational Resources Information Center
Chemical and Engineering News, 1973
1973-01-01
Discusses socioeconomic problems of pet population explosion and recommends the conduct of educational programs and the implementation of surgical sterilization as a short-term answer to dog and cat control. Also considered are problems of using chemical contraceptives in human population control. (CC)
Mass synchronization: Occurrence and its control with possible applications to brain dynamics
NASA Astrophysics Data System (ADS)
Chandrasekar, V. K.; Sheeba, Jane H.; Lakshmanan, M.
2010-12-01
Occurrence of strong or mass synchronization of a large number of neuronal populations in the brain characterizes its pathological states. In order to establish an understanding of the mechanism underlying such pathological synchronization, we present a model of coupled populations of phase oscillators representing the interacting neuronal populations. Through numerical analysis, we discuss the occurrence of mass synchronization in the model, where a source population which gets strongly synchronized drives the target populations onto mass synchronization. We hypothesize and identify a possible cause for the occurrence of such a synchronization, which is so far unknown: Pathological synchronization is caused not just because of the increase in the strength of coupling between the populations but also because of the strength of the strong synchronization of the drive population. We propose a demand controlled method to control this pathological synchronization by providing a delayed feedback where the strength and frequency of the synchronization determine the strength and the time delay of the feedback. We provide an analytical explanation for the occurrence of pathological synchronization and its control in the thermodynamic limit.
Applications of biological control in resistant host-pathogen systems.
White, Steven M; White, K A Jane
2005-09-01
Insect pest species can have devastating effects on crops. Control of these insect pests is usually achieved by using chemical insecticides. However, there has been much cause for concern with their overuse. Consequently, research has been carried out into alternative forms of control, in particular biological control methods. Recent laboratory studies have indicated that these natural forms of control can induce resistant strains of insect pest. In this paper we present a discrete-time host-pathogen model to describe the interaction between a host (insect species) that can develop a resistant strain and a pathogen (biological control) that can be externally applied to the system. For this model we use a single-state variable for the host population. We show that the proportion of resistance in the population impacts on the viability of the host population. Moreover, when the host population does persist, we explore the interaction between host susceptibility and host population levels. The different scenarios which arise are explained ecologically in terms of trade-offs in intrinsic growth rates, disease susceptibility and intraspecific host competition for the resistant subclass.
Complex numerical responses to top-down and bottom-up processes in vertebrate populations.
Sinclair, A R E; Krebs, Charles J
2002-01-01
Population growth rate is determined in all vertebrate populations by food supplies, and we postulate bottom-up control as the universal primary standard. But this primary control system can be overridden by three secondary controls: top-down processes from predators, social interactions within the species and disturbances. Different combinations of these processes affect population growth rates in different ways. Thus, some relationships between growth rate and density can be hyperbolic or even have multiple nodes. We illustrate some of these in marsupial, ungulate and rabbit populations. Complex interactions between food, predators, environmental disturbance and social behaviour produce the myriad observations of population growth in nature, and we need to develop generalizations to classify populations. Different animal groups differ in the combination of these four processes that affect them, in their growth rates and in their vulnerability to extinction. Because conservation and management of populations depend critically on what factors drive population growth, we need to develop universal generalizations that will relieve us from the need to study every single population before we can make recommendations for management. PMID:12396514
Uncovering the transmission dynamics of Plasmodium vivax using population genetics
Barry, Alyssa E.; Waltmann, Andreea; Koepfli, Cristian; Barnadas, Celine; Mueller, Ivo
2015-01-01
Population genetic analysis of malaria parasites has the power to reveal key insights into malaria epidemiology and transmission dynamics with the potential to deliver tools to support control and elimination efforts. Analyses of parasite genetic diversity have suggested that Plasmodium vivax populations are more genetically diverse and less structured than those of Plasmodium falciparum indicating that P. vivax may be a more ancient parasite of humans and/or less susceptible to population bottlenecks, as well as more efficient at disseminating its genes. These population genetic insights into P. vivax transmission dynamics provide an explanation for its relative resilience to control efforts. Here, we describe current knowledge on P. vivax population genetic structure, its relevance to understanding transmission patterns and relapse and how this information can inform malaria control and elimination programmes. PMID:25891915
Population control methods in stochastic extinction and outbreak scenarios.
Segura, Juan; Hilker, Frank M; Franco, Daniel
2017-01-01
Adaptive limiter control (ALC) and adaptive threshold harvesting (ATH) are two related control methods that have been shown to stabilize fluctuating populations. Large variations in population abundance can threaten the constancy and the persistence stability of ecological populations, which may impede the success and efficiency of managing natural resources. Here, we consider population models that include biological mechanisms characteristic for causing extinctions on the one hand and pest outbreaks on the other hand. These models include Allee effects and the impact of natural enemies (as is typical of forest defoliating insects). We study the impacts of noise and different levels of biological parameters in three extinction and two outbreak scenarios. Our results show that ALC and ATH have an effect on extinction and outbreak risks only for sufficiently large control intensities. Moreover, there is a clear disparity between the two control methods: in the extinction scenarios, ALC can be effective and ATH can be counterproductive, whereas in the outbreak scenarios the situation is reversed, with ATH being effective and ALC being potentially counterproductive.
Simulated population responses of common carp to commercial exploitation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weber, Michael J.; Hennen, Matthew J.; Brown, Michael L.
2011-12-01
Common carp Cyprinus carpio is a widespread invasive species that can become highly abundant and impose deleterious ecosystem effects. Thus, aquatic resource managers are interested in controlling common carp populations. Control of invasive common carp populations is difficult, due in part to the inherent uncertainty of how populations respond to exploitation. To understand how common carp populations respond to exploitation, we evaluated common carp population dynamics (recruitment, growth, and mortality) in three natural lakes in eastern South Dakota. Common carp exhibited similar population dynamics across these three systems that were characterized by consistent recruitment (ages 3 to 15 years present),more » fast growth (K = 0.37 to 0.59), and low mortality (A = 1 to 7%). We then modeled the effects of commercial exploitation on size structure, abundance, and egg production to determine its utility as a management tool to control populations. All three populations responded similarly to exploitation simulations with a 575-mm length restriction, representing commercial gear selectivity. Simulated common carp size structure modestly declined (9 to 37%) in all simulations. Abundance of common carp declined dramatically (28 to 56%) at low levels of exploitation (0 to 20%) but exploitation >40% had little additive effect and populations were only reduced by 49 to 79% despite high exploitation (>90%). Maximum lifetime egg production was reduced from 77 to 89% at a moderate level of exploitation (40%), indicating the potential for recruitment overfishing. Exploitation further reduced common carp size structure, abundance, and egg production when simulations were not size selective. Our results provide insights to how common carp populations may respond to exploitation. Although commercial exploitation may be able to partially control populations, an integrated removal approach that removes all sizes of common carp has a greater chance of controlling population abundance and reducing perturbations induced by this invasive species.« less
Reproductive adaptation in Drosophila exposed to oxygen-enriched atmospheres
NASA Technical Reports Server (NTRS)
Kloek, G.; Winkle, L.
1979-01-01
Ten successive generations of a Drosophila melanogaster population were exposed to an atmospheric mix of 50% oxygen/50% nitrogen at standard pressure. This atmospheric mix has been shown to be toxic to this species and causes significantly shortened life span. By the fifth generation, survivorship and life span for the first 25-30 days were identical to control populations and total life span was shorter by only a few days. Egg-laying rates were stable in the experimental populations but below those of the controls. Hatching success was identical between experimental and control populations. Even though the egg-laying rates were lower in 50% oxygen, it was concluded that the population had adapted and could maintain a stable population in these conditions. The near-normal life spans, normal hatching rates, and overall population stability, exhibited following five generations of adaptation, were considered sufficient to allow continued reproduction in spite of a reduced egg-laying rate.
Reproductive adaptation in Drosophila exposed to oxygen-enriched atmospheres.
Kloek, G; Winkle, L
1979-04-01
Ten successive generations of a Drosophila melanogaster population were exposed to an atmospheric mix of 50% oxygen/50% nitrogen at standard pressure. This atmospheric mix has been shown to be toxic to this species and causes significantly shortened life span. By the fifth generation, survivorship and life span for the first 25-30 days were identical to control populations and total life span was shorter by only a few days. Egg-laying rates were stable in the experimental populations but below those of the controls. Hatching success was identical between experimental and control populations. Even though the egg-laying rates were lower in 50% oxygen, it was concluded that the population had adapted and could maintain a stable population in these conditions. The near-normal life spans, normal hatching rates, and overall population stability, exhibited following five generations of adaptation, were considered sufficient to allow continued reproduction in spite of a reduced egg-laying rate.
Population versus hospital controls for case-control studies on cancers in Chinese hospitals
2011-01-01
Background Correct control selection is crucial to the internal validity of case-control studies. Little information exists on differences between population and hospital controls in case-control studies on cancers in Chinese hospital setting. Methods We conducted three parallel case-control studies on leukemia, breast and colorectal cancers in China between 2009 and 2010, using population and hospital controls to separately match 540 incident cases by age, gender and residency at a 1:1 ratio. Demographic and lifestyle factors were measured using a validated questionnaire in face-to-face interview. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained using conditional logistic regression analyses. Results The two control groups had closely similar exposure distributions of 15 out of 16 factors, with the only exception being that hospital controls were less likely to have a BMI ≥ 25 (OR = 0.71, 95% CI: 0.54, 0.93). For exposure of green tea drinking, the adjusted ORs (95% CIs) comparing green tealeaves intake ≥ 1000 grams annually with non-drinkers were 0.51 (0.31, 0.83) and 0.21 (0.27, 0.74) for three cancers combined, 0.06 (0.01, 0.61) and 0.07 (0.01, 0.47) for breast cancer, 0.52 (0.29, 0.94) and 0.45 (0.25, 0.82) for colorectal cancer, 0.65 (0.08, 5.63) and 0.57 (0.07, 4.79) for leukemia using hospital and population controls respectively. Conclusions The study found that hospital controls were comparable with population controls for most demographic characteristics and lifestyle factors measured, but there was a slight difference between the two control groups. Hospital outpatients provide a satisfactory control group in hospital-based case-control study in the Chinese hospital setting. PMID:22171783
Population versus hospital controls for case-control studies on cancers in Chinese hospitals.
Li, Lin; Zhang, Min; Holman, D'Arcy
2011-12-15
Correct control selection is crucial to the internal validity of case-control studies. Little information exists on differences between population and hospital controls in case-control studies on cancers in Chinese hospital setting. We conducted three parallel case-control studies on leukemia, breast and colorectal cancers in China between 2009 and 2010, using population and hospital controls to separately match 540 incident cases by age, gender and residency at a 1:1 ratio. Demographic and lifestyle factors were measured using a validated questionnaire in face-to-face interview. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained using conditional logistic regression analyses. The two control groups had closely similar exposure distributions of 15 out of 16 factors, with the only exception being that hospital controls were less likely to have a BMI ≥ 25 (OR = 0.71, 95% CI: 0.54, 0.93). For exposure of green tea drinking, the adjusted ORs (95% CIs) comparing green tealeaves intake ≥ 1000 grams annually with non-drinkers were 0.51 (0.31, 0.83) and 0.21 (0.27, 0.74) for three cancers combined, 0.06 (0.01, 0.61) and 0.07 (0.01, 0.47) for breast cancer, 0.52 (0.29, 0.94) and 0.45 (0.25, 0.82) for colorectal cancer, 0.65 (0.08, 5.63) and 0.57 (0.07, 4.79) for leukemia using hospital and population controls respectively. The study found that hospital controls were comparable with population controls for most demographic characteristics and lifestyle factors measured, but there was a slight difference between the two control groups. Hospital outpatients provide a satisfactory control group in hospital-based case-control study in the Chinese hospital setting.
Does higher body mass index contribute to worse asthma control in an urban population?
Clerisme-Beaty, Emmanuelle M; Karam, Sabine; Rand, Cynthia; Patino, Cecilia M; Bilderback, Andrew; Riekert, Kristin A; Okelo, Sande O.; Diette, Gregory B.
2009-01-01
Background Epidemiologic findings support a positive association between asthma and obesity. Objective Determine whether obesity or increasing level of body mass index (BMI) are associated with worse asthma control in an ethnically diverse urban population. Methods Cross sectional assessment of asthma control was done in asthmatics recruited from primary care offices using four different validated asthma control questionnaires: the Asthma Control and Communication Instrument (ACCI), the Asthma Control Test (ACT), the Asthma Control Questionnaire (ACQ) and the Asthma Therapy Assessment Questionnaire (ATAQ). Multiple linear regression analysis was performed to evaluate the association between obesity and increasing BMI level and asthma control. Results Of 292 subjects mean age of 47 years, the majority were women (82%) and African American (67%). There was a high prevalence of obesity with 63%, with only 15% being normal weight. The mean score from all four questionnaires showed an average sub-optimal asthma control (mean score/maximum possible score): ACCI (8.3/19), ACT (15.4/ 25), ACQ (2.1/ 6), and ATAQ (1.3/ 4). Regression analysis showed no association between obesity or increasing BMI level and asthma control using all four questionnaires. This finding persisted even after adjusting for FEV1, smoking status, race, gender, selected co-morbid illnesses, and long-term asthma controller use. Conclusion Using four validated asthma control questionnaires, we failed to find an association between obesity and asthma control in an urban population with asthma. Weight loss may not be an appropriate strategy to improve asthma control in this population. Capsule Summary Using four different validated asthma control measures, there was no association between obesity or increasing body mass index and asthma control in a largely obese urban outpatient minority population. PMID:19615731
ERIC Educational Resources Information Center
Safara, Maryam; Ghasemi, Pejman
2017-01-01
The aim of this study was to evaluate the efficacy of yoga on spiritual intelligence in air traffic controllers in Tehran flight control center. This was a quasi-experimental research and the study population includes all air traffic controllers in Tehran flight control center. The sample consisted of 40 people of the study population that were…
Engeman, Richard; Hershberger, Troy; Orzell, Steve; Felix, Rodney; Killian, Gary; Woolard, John; Cornman, Jon; Romano, David; Huddleston, Chet; Zimmerman, Pat; Barre, Chris; Tillman, Eric; Avery, Michael
2014-06-01
Feral swine were targeted for control at Avon Park Air Force Range in south-central Florida to avert damage to sensitive wetland habitats on the 40,000-ha base. We conducted a 5-year study to assess impacts from control to this population that had been recreationally hunted for many years. Control was initiated in early 2009. The feral swine population was monitored from 2008 to 2012 using a passive tracking index (PTI) during the dry and wet seasons and using recreational hunter take rates from the dry season. All three indices showed substantial feral swine declines after implementing control, with indices leveling for the final two study years. Military missions and recreational hunting seasons impacted temporal and spatial consistency of control application, thereby limiting further impacts of control efforts on the feral swine population. The PTI was also able to monitor coyotes, another invasive species on the base, and detect Florida black bear and Florida panther, species of particular concern.
Goitom, Eyerusalem; Kilsdonk, Laurens J; Brans, Kristien; Jansen, Mieke; Lemmens, Pieter; De Meester, Luc
2018-01-01
There is growing evidence of rapid genetic adaptation of natural populations to environmental change, opening the perspective that evolutionary trait change may subsequently impact ecological processes such as population dynamics, community composition, and ecosystem functioning. To study such eco-evolutionary feedbacks in natural populations, however, requires samples across time. Here, we capitalize on a resurrection ecology study that documented rapid and adaptive evolution in a natural population of the water flea Daphnia magna in response to strong changes in predation pressure by fish, and carry out a follow-up mesocosm experiment to test whether the observed genetic changes influence population dynamics and top-down control of phytoplankton. We inoculated populations of the water flea D. magna derived from three time periods of the same natural population known to have genetically adapted to changes in predation pressure in replicate mesocosms and monitored both Daphnia population densities and phytoplankton biomass in the presence and absence of fish. Our results revealed differences in population dynamics and top-down control of algae between mesocosms harboring populations from the time period before, during, and after a peak in fish predation pressure caused by human fish stocking. The differences, however, deviated from our a priori expectations. An S-map approach on time series revealed that the interactions between adults and juveniles strongly impacted the dynamics of populations and their top-down control on algae in the mesocosms, and that the strength of these interactions was modulated by rapid evolution as it occurred in nature. Our study provides an example of an evolutionary response that fundamentally alters the processes structuring population dynamics and impacts ecosystem features.
Optimal intervention strategies for cholera outbreak by education and chlorination
NASA Astrophysics Data System (ADS)
Bakhtiar, Toni
2016-01-01
This paper discusses the control of infectious diseases in the framework of optimal control approach. A case study on cholera control was studied by considering two control strategies, namely education and chlorination. We distinct the former control into one regarding person-to-person behaviour and another one concerning person-to-environment conduct. Model are divided into two interacted populations: human population which follows an SIR model and pathogen population. Pontryagin maximum principle was applied in deriving a set of differential equations which consists of dynamical and adjoin systems as optimality conditions. Then, the fourth order Runge-Kutta method was exploited to numerically solve the equation system. An illustrative example was provided to assess the effectiveness of the control strategies toward a set of control scenarios.
Zalewski, Andrzej; Zalewska, Hanna; Lunneryd, Sven-Gunnar; André, Carl; Mikusiński, Grzegorz
2016-01-01
Eradication and population reductions are often used to mitigate the negative impacts of non-native invasive species on native biodiversity. However, monitoring the effectiveness of non-native species control programmes is necessary to evaluate the efficacy of these measures. Genetic monitoring could provide valuable insights into temporal changes in demographic, ecological, and evolutionary processes in invasive populations being subject to control programmes. Such programmes should cause a decrease in effective population size and/or in genetic diversity of the targeted non-native species and an increase in population genetic structuring over time. We used microsatellite DNA data from American mink (Neovison vison) to determine whether the removal of this predator on the Koster Islands archipelago and the nearby Swedish mainland affected genetic variation over six consecutive years of mink culling by trappers as part of a population control programme. We found that on Koster Islands allelic richness decreased (from on average 4.53 to 3.55), genetic structuring increased, and effective population size did not change. In contrast, the mink population from the Swedish coast showed no changes in genetic diversity or structure, suggesting the stability of this population over 6 years of culling. Effective population size did not change over time but was higher on the coast than on the islands across all years. Migration rates from the islands to the coast were almost two times higher than from the coast to the islands. Most migrants leaving the coast were localised on the southern edge of the archipelago, as expected from the direction of the sea current between the two sites. Genetic monitoring provided valuable information on temporal changes in the population of American mink suggesting that this approach can be used to evaluate and improve control programmes of invasive vertebrates.
1993-02-09
Birth Control Measures [RENKOU YU JINGJI25 Oct] 37 Conference on Population Problems in Southwest [RENKOU YU JINGJI 25 Oct] -. 38 Southern JiangsU... Birth Control Measures 93CE0171A Beijing RENKOU YU JINGJI [POPULATION AND ECONOMICS] in Chinese No 74, 25 Oct 92 pp 43-45 [Article by Deng Guosheng...6772 0948 0524), affiliated with the Population Department of Jiangxi Teachers College: "More Attention Needs To Be Paid to Our Poor Birth Control Results
Optimal Harvesting in an Age-Structured Predator-Prey Model
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fister, K. Renee; Lenhart, Suzanne
2006-06-15
We investigate optimal harvesting control in a predator-prey model in which the prey population is represented by a first-order partial differential equation with age-structure and the predator population is represented by an ordinary differential equation in time. The controls are the proportions of the populations to be harvested, and the objective functional represents the profit from harvesting. The existence and uniqueness of the optimal control pair are established.
Existence and characterization of optimal control in mathematics model of diabetics population
NASA Astrophysics Data System (ADS)
Permatasari, A. H.; Tjahjana, R. H.; Udjiani, T.
2018-03-01
Diabetes is a chronic disease with a huge burden affecting individuals and the whole society. In this paper, we constructed the optimal control mathematical model by applying a strategy to control the development of diabetic population. The constructed mathematical model considers the dynamics of disabled people due to diabetes. Moreover, an optimal control approach is proposed in order to reduce the burden of pre-diabetes. Implementation of control is done by preventing the pre-diabetes develop into diabetics with and without complications. The existence of optimal control and characterization of optimal control is discussed in this paper. Optimal control is characterized by applying the Pontryagin minimum principle. The results indicate that there is an optimal control in optimization problem in mathematics model of diabetic population. The effect of the optimal control variable (prevention) is strongly affected by the number of healthy people.
Population remains top priority for China.
Li, H
1998-04-01
China, whose population was 430 million in 1840, is facing a population total of 1.3 billion in 2000. Population increased rapidly in the country during the 1950s, but early efforts at population control were abandoned from the start of the Cultural Revolution in 1966 until the 1970s. Today, the importance of family planning (FP) is recognized throughout Chinese society. With 20 million newborns adding 13 million people to the population each year, controlling the population increase will remain a top priority of China's population policy. Other priorities include 1) increasing the quality of life of the population by improving health, promoting literacy, and developing human resources; 2) facing the impact of population aging; 3) struggling to overcome the poverty experienced by 50 million people; and 4) dealing with the imbalanced sex ratio of newborns. China has been attempting to institute strategies to implement the Program of Action adopted by the 1994 International Conference on Population and Development and is attempting to adopt an integrated approach to population programs that combines FP with development measures and the delivery of multiple services to enhance reproductive health. Since 1984, China has worked with Japan's JOICFP on an Integrated Project that offers FP, maternal and child health services, and parasite control.
Estimating finite-population reproductive numbers in heterogeneous populations.
Keegan, Lindsay T; Dushoff, Jonathan
2016-05-21
The basic reproductive number, R0, is one of the most important epidemiological quantities. R0 provides a threshold for elimination and determines when a disease can spread or when a disease will die out. Classically, R0 is calculated assuming an infinite population of identical hosts. Previous work has shown that heterogeneity in the host mixing rate increases R0 in an infinite population. However, it has been suggested that in a finite population, heterogeneity in the mixing rate may actually decrease the finite-population reproductive numbers. Here, we outline a framework for discussing different types of heterogeneity in disease parameters, and how these affect disease spread and control. We calculate "finite-population reproductive numbers" with different types of heterogeneity, and show that in a finite population, heterogeneity has complicated effects on the reproductive number. We find that simple heterogeneity decreases the finite-population reproductive number, whereas heterogeneity in the intrinsic mixing rate (which affects both infectiousness and susceptibility) increases the finite-population reproductive number when R0 is small relative to the size of the population and decreases the finite-population reproductive number when R0 is large relative to the size of the population. Although heterogeneity has complicated effects on the finite-population reproductive numbers, its implications for control are straightforward: when R0 is large relative to the size of the population, heterogeneity decreases the finite-population reproductive numbers, making disease control or elimination easier than predicted by R0. Copyright © 2016 Elsevier Ltd. All rights reserved.
The rural-to-urban migrant population in China: gloomy prospects for tuberculosis control.
Tobe, Ruoyan Gai; Xu, Lingzhong; Song, Peipei; Huang, Yong
2011-12-01
The migrant population is a population with a high risk of tuberculosis (TB) infection and transmission. Globally, migration is likely to have a significant impact on TB epidemiology, particularly in countries that receive substantial numbers of migrants from countries with a high infection burden. China, a country with the world's second highest TB burden, faces a considerable increase in the number of rural-to-urban migrants. This population has a significant impact on urban TB epidemics and is specifically targeted by national guidelines for TB control. TB control among the migrant population has had relatively poor outcomes. Barriers to detection and treatment have both financial and non-financial aspects, such as the "migratory" nature of the migrant population, their marginalized working and living environment, poor financial status, little awareness of TB, inadequate referral to TB dispensaries, and potential social stigma in the workplace. Currently, the free TB treatment policy has limited ability to relieve the financial burden on most migrant TB patients as would allow optimal outcomes of TB detection and treatment. Universal health insurance coverage and fostering of personnel in community-based primary health care for the rural-to- urban migrant population represent two pillars of successful TB control.
ENDERSBY, N. M.; HOFFMANN, A. A.; WHITE, V. L.; LOWENSTEIN, S.; RITCHIE, S.; JOHNSON, P. H.; RAPLEY, L. P.; RYAN, P. A.; NAM, V. S.; YEN, N. T.; KITTIYAPONG, P.; WEEKS, A. R.
2009-01-01
The distribution of Aedes aegypti (L.) in Australia is currently restricted to northern Queensland, but it has been more extensive in the past. In this study, we evaluate the genetic structure of Ae. aegypti populations in Australia and Vietnam and consider genetic differentiation between mosquitoes from these areas and those from a population in Thailand. Six microsatellites and two exon primed intron crossing markers were used to assess isolation by distance across all populations and also within the Australian sample. Investigations of founder effects, amount of molecular variation between and within regions and comparison of FST values among Australian and Vietnamese populations were made to assess the scale of movement of Ae. aegypti. Genetic control methods are under development for mosquito vector populations including the dengue vector Ae. aegypti. The success of these control methods will depend on the population structure of the target species including population size and rates of movement among populations. Releases of modified mosquitoes could target local populations that show a high degree of isolation from surrounding populations, potentially allowing new variants to become established in one region with eventual dispersal to other regions. PMID:19769038
Evidence-based control of canine rabies: a critical review of population density reduction
Morters, Michelle K; Restif, Olivier; Hampson, Katie; Cleaveland, Sarah; Wood, James L N; Conlan, Andrew J K
2013-01-01
Control measures for canine rabies include vaccination and reducing population density through culling or sterilization. Despite the evidence that culling fails to control canine rabies, efforts to reduce canine population density continue in many parts of the world. The rationale for reducing population density is that rabies transmission is density-dependent, with disease incidence increasing directly with host density. This may be based, in part, on an incomplete interpretation of historical field data for wildlife, with important implications for disease control in dog populations. Here, we examine historical and more recent field data, in the context of host ecology and epidemic theory, to understand better the role of density in rabies transmission and the reasons why culling fails to control rabies. We conclude that the relationship between host density, disease incidence and other factors is complex and may differ between species. This highlights the difficulties of interpreting field data and the constraints of extrapolations between species, particularly in terms of control policies. We also propose that the complex interactions between dogs and people may render culling of free-roaming dogs ineffective irrespective of the relationship between host density and disease incidence. We conclude that vaccination is the most effective means to control rabies in all species. PMID:23004351
Asherson, P; Stes, S; Nilsson Markhed, M; Berggren, L; Svanborg, P; Kutzelnigg, A; Deberdt, W
2015-06-01
To investigate the effects of atomoxetine on emotional control in adults with ADHD. We performed an integrated analysis using individual patient data pooled from three Eli Lilly-sponsored studies. An integrated analysis can be viewed as a meta-analysis of individual patient-level data, rather than study-level summary data. Two populations were identified: a large sample of patients with pre-treatment baseline data (the "overall population"; n=2846); and a subset of these patients with placebo-controlled efficacy data from baseline to 10 or 12 weeks after initiating treatment (the "placebo-controlled population"; n=829). At baseline, in the overall population, ∼50% of ADHD patients had BRIEF-AS (Behavior Rating Inventory of Executive Function-Adult Version Self-Report) Emotional control subscores between 21 and 30, compared with ∼10% of normative subjects in the BRIEF-A manual. At endpoint, in the placebo-controlled population, atomoxetine led to a small (effect size 0.19) but significant (P=0.013) treatment effect for emotional control. The effect size was 0.32 in patients with BRIEF-AS Emotional control scores>20 at baseline. Improvements in emotional control correlated with improvements in the core ADHD symptoms and quality-of-life. As deficient emotional control is associated with impaired social, educational and occupational functioning over and above that explained by core ADHD symptoms alone, improvements in emotional control may be clinically relevant. At baseline, adults with ADHD were more likely to have impaired emotional control than normative subjects. In the adult ADHD patients, atomoxetine treatment was associated with improvements in emotional control, as well as in core ADHD symptoms and quality-of-life. Copyright © 2015. Published by Elsevier Masson SAS.
Broder, Michael S; Neary, Maureen P; Chang, Eunice; Ludlam, William H
2015-12-01
Resource utilization and costs in Cushing's disease (CD) patients have not been studied extensively. We compared CD patients with diabetes mellitus (DM) patients and population-based controls to characterize differences in utilization and costs. Using 2008-2012 MarketScan® database, we identified three patient groups: (1) CD patients; (2) DM patients; and (3) population-based control patients without CD. DM and control patients were matched to CD patients by age, gender, region, and review year in a 2:1 ratio. Outcomes included annual healthcare resource utilization and costs. There were 1852 CD patients, 3704 DM patients and 3704 controls. Mean age was 42.9 years; 78.2 % were female. CD patients were hospitalized more frequently (19.3 %) than DM patients (11.0 %, p < .001) or controls (5.6 %, p < .001). CD patients visited the ED more frequently (25.4 %) than DM patients (21.1 %, p < .001) or controls (14.3 %, p < .001). CD patients had more office visits than DM patients (19.1 vs. 10.7, p < .001) or controls (7.1, p < .001). CD patients on average filled more prescriptions than DM patients (51.7 vs. 42.7, p < .001) or controls (20.5, p < .001). Mean total healthcare costs for CD patients were $26,269 versus $12,282 for DM patients (p < .001) and $5869 for controls (p < .001). CD patients had significantly higher annual rates of healthcare resource utilization compared to matched DM patients and population controls without CD. CD patient costs were double DM costs and quadruple control costs. This study puts into context the additional burdens of CD over DM, a common, chronic endocrine condition affecting multiple organ systems, and population controls.
Catholic Perspectives on Population Issues. Population Bulletin, Vol. 35, No. 6.
ERIC Educational Resources Information Center
Murphy, Francis X.
The bulletin investigates the major positions held by the Catholic Church toward population problems. Separate sections discuss the demographic debate, traditional church teaching, the birth control movement, the Vatican Council II and the Papal Birth Control Commission, Pope Paul's 1968 Encyclical against contraception, the 1980 Synod of Bishops,…
NASA Astrophysics Data System (ADS)
Liang, Juhua; Tang, Sanyi; Cheke, Robert A.
2016-07-01
Pest resistance to pesticides is usually managed by switching between different types of pesticides. The optimal switching time, which depends on the dynamics of the pest population and on the evolution of the pesticide resistance, is critical. Here we address how the dynamic complexity of the pest population, the development of resistance and the spraying frequency of pulsed chemical control affect optimal switching strategies given different control aims. To do this, we developed novel discrete pest population growth models with both impulsive chemical control and the evolution of pesticide resistance. Strong and weak threshold conditions which guarantee the extinction of the pest population, based on the threshold values of the analytical formula for the optimal switching time, were derived. Further, we addressed switching strategies in the light of chosen economic injury levels. Moreover, the effects of the complex dynamical behaviour of the pest population on the pesticide switching times were also studied. The pesticide application period, the evolution of pesticide resistance and the dynamic complexity of the pest population may result in complex outbreak patterns, with consequent effects on the pesticide switching strategies.
Marcet, PL; Mora, MS; Cutrera, AP; Jones, L; Gürtler, RE; Kitron, U; Dotson, EM
2008-01-01
To gain an understanding of the genetic structure and dispersal dynamics of T. infestans populations, we analyzed the multilocus genotype of 10 microsatellite loci for 352 T. infestans collected in 21 houses of 11 rural communities in October 2002. Genetic structure was analyzed at the community and house compound levels. Analysis revealed that vector control actions affected the genetic structure of T. infestans populations. Bug populations from communities under sustained vector control (core area) were highly structured and genetic differentiation between neighboring house compounds was significant. In contrast, bug populations from communities with sporadic vector control actions were more homogeneous and lacked defined genetic clusters. Genetic differentiation between population pairs did not fit a model of isolation by distance at the microgeographical level. Evidence consistent with flight or walking bug dispersal was detected within and among communities, dispersal was more female-biased in the core area and results suggested that houses received immigrants from more than one source. Putative sources and mechanisms of re-infestation are described. These data may be use to design improved vector control strategies PMID:18773972
Population control II: The population establishment today.
Hartmann, B
1997-01-01
Although population assistance represents a relatively small share of official development assistance, it influences many other aspects of development planning. The organizations that comprise the population establishment have a common purpose--the reduction of population growth in the Third World--but they are not homogeneous and sometimes have conflicting goals and strategies. National governments, multilateral agencies, nongovernmental organizations, foundations, academic centers, and pressure groups all contribute to creating and sustaining what has become a virtual population control industry. Through scholarships, travel grants, awards, and favorable publicity, Third World elites have been encouraged to join the population establishment. The World Bank, the U.S. Agency for International Development, and the U.N. Fund for Population Activities have pursued explicit strategies for pressuring Third World governments to design and implement population policies, most recently in Africa.
Dalgaard, Lars Skov; Nørgaard, Mette; Povlsen, Johan Vestergaard; Jespersen, Bente; Jensen-Fangel, Søren; Ellermann-Eriksen, Svend; Østergaard, Lars; Schønheyder, Henrik Carl; Søgaard, Ole Schmeltz
♦ BACKGROUND: The incidence of bacteremia and fungemia (BAF) is largely unknown in end-stage renal disease (ESRD) patients initiating peritoneal dialysis (PD). ♦ OBJECTIVE: The main objective was to estimate and compare incidence rates of first episodes of BAF in incident PD patients and a comparison cohort. A secondary objective was to compare causative agents and 30-day post-BAF mortality between PD patients and the comparison cohort. ♦ METHODS: Design: Observational cohort study. Central and North Denmark regions. patients who initiated PD during 1995 - 2010. For each patient we sampled up to 10 controls from the general population matched on age, sex, and municipality. ♦ MAIN OUTCOME: Data on positive blood cultures were retrieved from electronic microbiology databases covering the 2 regions. We calculated incidence rates (IRs) of first-time BAF for PD patients and population controls. Incidence-rate ratios (IRRs) were calculated to compare these rates. Thirty-day mortality was estimated by Kaplan-Meier analysis. ♦ RESULTS: Among 1,024 PD patients and 10,215 population controls, we identified 75 and 282 episodes of BAF, respectively. Incidence rates of BAF were 4.7 (95% confidence interval [CI], 3.8 - 5.9) per 100 person-years of follow-up (PYFU) in PD patients and 0.5 (95% CI, 0.4 - 0.5) per 100 PYFU in population controls (IRR = 10.4; 95% CI, 8.1 - 13.5). In PD patients, the most frequent microorganisms were Escherichia coli (18.7%) and Staphylococcus aureus (13.3%). Escherichia coli (27.3%) also ranked first among population controls. Thirty-day mortality following BAF was 20.8% (95% CI, 12.6 - 31.0) and 20.7% (95% CI, 16.3 - 25.9) among PD patients and population controls, respectively. ♦ CONCLUSIONS: Peritoneal dialysis patients are at markedly higher risk of BAF than population controls. Causative agents and the 30-day post-BAF mortality were similar in the 2 cohorts. Copyright © 2016 International Society for Peritoneal Dialysis.
Rabies Vaccination Targets for Stray Dog Populations
Leung, Tiffany; Davis, Stephen A.
2017-01-01
The role of stray dogs in the persistence of domestic dog rabies, and whether removal of such dogs is beneficial, remains contentious issues for control programs seeking to eliminate rabies. While a community might reach the WHO vaccination target of 70% for dogs that can be handled, the stray or neighborhood dogs that are too wary of humans to be held are a more problematic population to vaccinate. Here, we present a method to estimate vaccination targets for stray dogs when the dog population is made up of stray, free-roaming, and confined dogs, where the latter two types are considered to have an identifiable owner. The control effort required for stray dogs is determined by the type-reproduction number, T1, the number of stray dogs infected by one rabid stray dog either directly or via any chain of infection involving owned dogs. Like the basic reproduction number R0 for single host populations, T1 determines the vaccination effort required to control the spread of disease when control is targeted at one host type, and there is a mix of host types. The application of T1 to rabies in mixed populations of stray and owned dogs is novel. We show that the outcome is sensitive to the vaccination coverage in the owned dog population, such that if vaccination rates of owned dogs were too low then no control effort targeting stray dogs is able to control or eliminate rabies. The required vaccination level also depends on the composition of the dog population, where a high proportion of either stray or free-roaming dogs implies unrealistically high vaccination levels are required to prevent rabies. We find that the required control effort is less sensitive to continuous culling that increases the death rate of stray dogs than to changes in the carrying capacity of the stray dog population. PMID:28451589
Intraspecific Competition and Population Dynamics of Aedes aegypti
NASA Astrophysics Data System (ADS)
Paixão, C. A.; Charret, I. C.; Lima, R. R.
2012-04-01
We report computational simulations for the evolution of the population of the dengue vector, Aedes aegypti mosquitoes. The results suggest that controlling the mosquito population, on the basis of intraspecific competition at the larval stage, can be an efficient mechanism for controlling the spread of the epidemic. The results also show the presence of a kind of genetic evolution in vector population, which results mainly in increasing the average lifespan of individuals in adulthood.
Identifying Reservoirs of Infection: A Conceptual and Practical Challenge
2002-01-01
Many infectious agents, especially those that cause emerging diseases, infect more than one host species. Managing reservoirs of multihost pathogens often plays a crucial role in effective disease control. However, reservoirs remain variously and loosely defined. We propose that reservoirs can only be understood with reference to defined target populations. Therefore, we define a reservoir as one or more epidemiologically connected populations or environments in which the pathogen can be permanently maintained and from which infection is transmitted to the defined target population. Existence of a reservoir is confirmed when infection within the target population cannot be sustained after all transmission between target and nontarget populations has been eliminated. When disease can be controlled solely by interventions within target populations, little knowledge of potentially complex reservoir infection dynamics is necessary for effective control. We discuss the practical value of different approaches that may be used to identify reservoirs in the field. PMID:12498665
Experimental evolution reveals high insecticide tolerance in Daphnia inhabiting farmland ponds
Jansen, Mieke; Coors, Anja; Vanoverbeke, Joost; Schepens, Melissa; De Voogt, Pim; De Schamphelaere, Karel A C; De Meester, Luc
2015-01-01
Exposure of nontarget populations to agricultural chemicals is an important aspect of global change. We quantified the capacity of natural Daphnia magna populations to locally adapt to insecticide exposure through a selection experiment involving carbaryl exposure and a control. Carbaryl tolerance after selection under carbaryl exposure did not increase significantly compared to the tolerance of the original field populations. However, there was evolution of a decreased tolerance in the control experimental populations compared to the original field populations. The magnitude of this decrease was positively correlated with land use intensity in the neighbourhood of the ponds from which the original populations were sampled. The genetic change in carbaryl tolerance in the control rather than in the carbaryl treatment suggests widespread selection for insecticide tolerance in the field associated with land use intensity and suggests that this evolution comes at a cost. Our data suggest a strong impact of current agricultural land use on nontarget natural Daphnia populations. PMID:26029258
Targeting Hispanic populations: future research and prevention strategies.
Ramirez, A G; McAlister, A; Gallion, K J; Villarreal, R
1995-01-01
Minority populations face a wide variety of economic, institutional, and cultural barriers to health care. These barriers and low levels of education and income pose significant challenges for health professionals in developing cancer research and prevention-control strategies. It is suggested that specific segments of Hispanic populations fit the model of an underdeveloped country in the intermediate stage of epidemiological transition. Since noncommunicable diseases have not yet fully emerged in some of these Hispanic population segments, the opportunity exists to apply primordial prevention strategies. Such campaigns would focus on dissuading members of these populations from adopting negative health behaviors while promoting positive lifestyle choices. Optimal programs would increase cancer screening participation and discourage risk behaviors through community-oriented, population-based interventions. Future directions in prevention and control efforts for minority populations should include expanded health insurance coverage, improved access to health care, greater emphasis on minority recruitment in health care fields, focused epidemiologic and clinical research, and identification and replication of effective components within existing prevention-control programs. PMID:8741800
Strategic use of communication to market cancer prevention and control to vulnerable populations.
Kreps, Gary L
2008-01-01
There are significant challenges to communicating relevant cancer prevention and control information to health care consumers due both to the complexities of the health information to be communicated and the complexities of health communication, especially with vulnerable populations. The need for effective communication about cancer risks, early detection, prevention, care, and survivorship is particularly acute, yet also tremendously complex, for reaching vulnerable populations, those groups of people who are most likely to suffer significantly higher levels of morbidity and mortality from cancers than other segments of the population. These vulnerable populations, typically the poorest, lowest educated, and most disenfranchised members of modern society, are heir to serious cancer-related health disparities. Vulnerable populations often have health literacy difficulties, cultural barriers, and economic challenges to accessing and making sense of relevant health information. This paper examines these challenges to communicating relevant information to vulnerable populations and suggests strategies for effectively using different communication media for marketing cancer prevention and control to reduce health disparities and promote public health.
Lebedev, Galina; Abo-Moch, Fauzi; Gafni, Guy; Ben-Yakir, David; Ghanim, Murad
2013-02-01
The onion thrips, Thrips tabaci Lindeman, is a major pest of several crop plants in the genus Allium, such as onions, garlic and chives. In Israel, these crops are grown in open fields and in protected housing. This thrips is usually controlled by the application of chemical insecticides. In recent years, spinosad, emamectin benzoate and carbosulfan have been the major insecticides used for the control of the onion thrips. In the last 4 years, growers of chives and green onion from several regions of Israel have reported a significant decrease in the efficacy of insecticides used to control the onion thrips. The susceptibility of 14 populations of the onion thrips, collected mainly from chives between the years 2007 and 2011, to spinosad, emamectin benzoate and carbosulfan was tested using a laboratory bioassay. The majority of the populations showed significant levels of resistance to at least one of the insecticides. LC(50) values calculated for two of the studied populations showed that the resistance factor for spinosad compared with the susceptible population is 21 393, for carbosulfan 54 and for emamectin benzoate 36. Only two populations, collected from organic farms, were susceptible to the insecticides tested. This is the first report of a high resistance level to spinosad, the major insecticide used to control the onion thrips. Resistance cases to spinosad were associated with failures to control the pest. Populations resistant to spinosad also had partial or complete resistance to other insecticides used for controlling the onion thrips. Copyright © 2012 Society of Chemical Industry.
Association of Dental Care with Adherence to HEDIS Measures
Mosen, David; Pihlstrom, Dan; Snyder, John; Smith, Ning; Shuster, Elizabeth; Rust, Kristal
2016-01-01
Context: The dental setting represents an unrealized opportunity to increase adherence to preventive services and improve health outcomes. Objective: To compare adherence to a subset of Healthcare Effectiveness Data and Information Set (HEDIS) measures among a population that received dental care with a population that did not receive dental care. Design: Using a retrospective cohort design, we identified 5216 adults who received regular dental care and 5216 persons who did not. The groups were matched on propensity scores, were followed for 3 years, and retained medical and dental benefits. Receipt of dental care was defined as 1 or more dental visits in each 12-month period. Main Outcome Measures: Outcome measures were assessed in a subpopulation that qualified for 1 of 5 HEDIS denominator groups (dental = 4184 patients; nondental = 3871 patients). They included 3 preventive measures (cervical, colorectal, and breast cancer screening), 4 chronic disease management services (hemoglobin A1c and low-density lipoprotein cholesterol testing, and nephropathy and retinopathy screening among the diabetes mellitus [DM] population), and 4 health outcome measures (poor glycemic control, low-density lipoprotein cholesterol control, blood pressure control in the DM population, and blood pressure control in the hypertensive population). Results: Dental care was associated with higher adherence to all three cancer screening measures, one of four disease management services (higher retinopathy screening), and three of four health outcomes (better glycemic control in the DM population and better blood pressure control in the DM and hypertensive populations). Conclusions: Dental care was associated with improved adherence to 7 of 11 HEDIS measures. PMID:26580145
Paul, Christine L; Turon, Heidi; Bonevski, Billie; Bryant, Jamie; McElduff, Patrick
2013-12-08
There is a clear disparity in smoking rates according to social disadvantage. In the absence of sufficiently robust data regarding effective strategies for reducing smoking prevalence in disadvantaged populations, understanding the views of tobacco control experts can assist with funding decisions and research agendas. A web-based cross-sectional survey was conducted with 192 respondents (response rate 65%) sampled from the Australian and New Zealand Tobacco Control Contacts list and a literature search. Respondents were asked to indicate whether a number of tobacco control strategies were perceived to be effective for each of: the general population; Aboriginal and Torres Strait Islander people; those with a low income; and people with a mental illness. A high proportion of respondents indicated that mass media and increased tobacco taxation (84% and 89% respectively) were effective for the general population. Significantly lower proportions reported these two strategies were effective for sub-populations, particularly Aboriginal and Torres Strait Islanders (58% and 63% respectively, p's < .0001). Subsidised medication was the only strategy associated with a greater proportion of respondents perceiving it to be effective in disadvantaged sub-populations compared to the general population. Tailored quit programs and culturally relevant programs were nominated as additional effective strategies for disadvantaged populations. Views about subsidised medications in particular, suggest the need for robust cost-effectiveness data relevant to disadvantaged groups to avoid wastage of scarce tobacco control resources. Strategies perceived to be effective for disadvantaged populations such as tailored or culturally relevant programs require rigorous evaluation so that potential adoption of these approaches is evidence-based.
2013-01-01
Background There is a clear disparity in smoking rates according to social disadvantage. In the absence of sufficiently robust data regarding effective strategies for reducing smoking prevalence in disadvantaged populations, understanding the views of tobacco control experts can assist with funding decisions and research agendas. Methods A web-based cross-sectional survey was conducted with 192 respondents (response rate 65%) sampled from the Australian and New Zealand Tobacco Control Contacts list and a literature search. Respondents were asked to indicate whether a number of tobacco control strategies were perceived to be effective for each of: the general population; Aboriginal and Torres Strait Islander people; those with a low income; and people with a mental illness. Results A high proportion of respondents indicated that mass media and increased tobacco taxation (84% and 89% respectively) were effective for the general population. Significantly lower proportions reported these two strategies were effective for sub-populations, particularly Aboriginal and Torres Strait Islanders (58% and 63% respectively, p’s < .0001). Subsidised medication was the only strategy associated with a greater proportion of respondents perceiving it to be effective in disadvantaged sub-populations compared to the general population. Tailored quit programs and culturally relevant programs were nominated as additional effective strategies for disadvantaged populations. Conclusions Views about subsidised medications in particular, suggest the need for robust cost-effectiveness data relevant to disadvantaged groups to avoid wastage of scarce tobacco control resources. Strategies perceived to be effective for disadvantaged populations such as tailored or culturally relevant programs require rigorous evaluation so that potential adoption of these approaches is evidence-based. PMID:24314097
Bower, Hannah; Andersson, Therese M-L; Crowther, Michael J; Dickman, Paul W; Lambe, Mats; Lambert, Paul C
2018-04-01
Expected or reference mortality rates are commonly used in the calculation of measures such as relative survival in population-based cancer survival studies and standardized mortality ratios. These expected rates are usually presented according to age, sex, and calendar year. In certain situations, stratification of expected rates by other factors is required to avoid potential bias if interest lies in quantifying measures according to such factors as, for example, socioeconomic status. If data are not available on a population level, information from a control population could be used to adjust expected rates. We have presented two approaches for adjusting expected mortality rates using information from a control population: a Poisson generalized linear model and a flexible parametric survival model. We used a control group from BCBaSe-a register-based, matched breast cancer cohort in Sweden with diagnoses between 1992 and 2012-to illustrate the two methods using socioeconomic status as a risk factor of interest. Results showed that Poisson and flexible parametric survival approaches estimate similar adjusted mortality rates according to socioeconomic status. Additional uncertainty involved in the methods to estimate stratified, expected mortality rates described in this study can be accounted for using a parametric bootstrap, but this might make little difference if using a large control population.
Wang, Yi; Huang, Wei; Siemann, Evan; Zou, Jianwen; Wheeler, Gregory S; Carrillo, Juli; Ding, Jianqing
2011-04-01
Invasive plants often have novel biotic interactions in their introduced ranges. Their defense to herbivory may differ from their native counterparts, potentially influencing the effectiveness of biological control. If invasive plants have decreased resistance but increased tolerance to enemies, insect herbivores may rapidly build up their populations but exert weak control. Moreover, resource availability to plants may affect the efficacy of biological control agents. We tested these predictions using Chinese tallow tree (Triadica sebifera) and two specialist herbivores (Heterapoderopsis bicallosicollis and Gadirtha inexacta) that are candidates for biological control. We performed a pair of field common garden experiments in China in which Triadica seedlings from the native or introduced range were grown in low or high light conditions and subjected to different levels of herbivory by each herbivore in a factorial design. We found that Heterapoderopsis achieved greater densities on tallow trees from the introduced range or when trees were grown in high light conditions. When Gadirtha was raised in the lab on tallow tree foliage we found that it performed better (larger pupal size) when fed foliage from introduced populations. However, introduced populations generally had greater herbivore tolerance such that the impact of each agent on plant performance was lower than on native populations despite higher herbivore loads. Tallow trees grew more slowly and achieved smaller sizes in lower light levels, but the impact of biological control agents was comparable to that found for higher light levels. Plants from introduced populations grew larger than those from native populations in all conditions. Our results suggest that reduced resistance and increased tolerance to herbivory in introduced populations may impede success of biological control programs. Biological control practitioners should include plants from the introduced range in the prerelease evaluation, which will help predict insect impact on target weeds.
A computer simulation model of Wolbachia invasion for disease vector population modification.
Guevara-Souza, Mauricio; Vallejo, Edgar E
2015-10-05
Wolbachia invasion has been proved to be a promising alternative for controlling vector-borne diseases, particularly Dengue fever. Creating computer models that can provide insight into how vector population modification can be achieved under different conditions would be most valuable for assessing the efficacy of control strategies for this disease. In this paper, we present a computer model that simulates the behavior of native mosquito populations after the introduction of mosquitoes infected with the Wolbachia bacteria. We studied how different factors such as fecundity, fitness cost of infection, migration rates, number of populations, population size, and number of introduced infected mosquitoes affect the spread of the Wolbachia bacteria among native mosquito populations. Two main scenarios of the island model are presented in this paper, with infected mosquitoes introduced into the largest source population and peripheral populations. Overall, the results are promising; Wolbachia infection spreads among native populations and the computer model is capable of reproducing the results obtained by mathematical models and field experiments. Computer models can be very useful for gaining insight into how Wolbachia invasion works and are a promising alternative for complementing experimental and mathematical approaches for vector-borne disease control.
Jones, Michael L.; Bergstedt, R.A.; Twohey, Michael B.; Fodale, Michael F.; Cuddy, Douglas W.; Slade, Jeffrey W.
2003-01-01
Compensatory mechanisms are demographic processes that tend to increase population growth rates at lower population density. These processes will tend to reduce the effectiveness of actions that use controls on reproductive success to suppress sea lamprey (Petromyzon marinus), an economically important pest in the Great Lakes. Historical evidence for compensatory mechanisms in sea lamprey populations was reviewed, and revealed: (1) strong evidence for shifts in sex ratios as sea lamprey abundance was reduced in the early years of the control program; (2) weak and equivocal evidence for increased growth rates of sea lamprey cohorts re-colonizing streams following a lampricide treatment; and (3) suggestions of other compensatory processes, such as earlier ages at metamorphosis, but with little empirical evidence. Larval size distribution data for cohorts in the first and second years following a lampricide treatment (26 pairs of cohorts in 20 streams) was analyzed and did not indicate a consistent pattern of more rapid growth of the first colonizing cohort (only 11 of 33 cases). To test for compensation between spawning and age-1 in sea lamprey populations, data were analyzed for 49 stream-years for which spawning female abundance was known and age-1 abundance was estimated in the following year. A fit of these data to a Ricker stock-recruitment function showed evidence for compensation, measured as reduced survival to age 1 at higher abundance of spawning females. More obvious, however, was a large amount of density-independent variation in survival, which tends to mask evidence for compensatory survival. The results were applied to a simple model that simulates sea lamprey populations and their control in a hypothetical lake. Control strategies that targeted reproductive success performed far less well than comparable strategies that targeted larval populations, because density-independent recruitment variation leads to occasional strong year classes even when spawner abundance is reduced to low levels through alternative control. It is concluded that further study of recruitment variation in lamprey populations is critical to rationalizing alternative controls that target reproductive success, and that recruitment variation needs to be incorporated into models used to evaluate sea lamprey control options.
Ji, Pingsheng; Wilson, Mark
2003-01-01
Sodium salicylate and ammonium sulfate were applied to leaf surfaces along with suspensions of the biological control agents Pseudomonas syringae Cit7(pNAH7), which catabolizes salicylate, and Cit7, which does not catabolize salicylate, to determine whether enhanced biological control of bacterial speck of tomato could be achieved. Foliar amendment with salicylate alone significantly enhanced the population size and the efficacy of Cit7(pNAH7), but not of Cit7, on tomato leaves. Application of ammonium sulfate alone did not result in enhanced population size or biological control efficacy of either Cit7(pNAH7) or Cit7; however, when foliar amendments with both sodium salicylate and ammonium sulfate were applied, a trend toward further increases in population size and biological control efficacy of Cit7(pNAH7) was observed. This study demonstrates the potential of using a selective carbon source to improve the efficacy of a bacterial biological control agent in the control of a bacterial plant disease and supports previous conclusions that the growth of P. syringae in the phyllosphere is primarily carbon limited and secondarily nitrogen limited. PMID:12571060
An optimal control strategies using vaccination and fogging in dengue fever transmission model
NASA Astrophysics Data System (ADS)
Fitria, Irma; Winarni, Pancahayani, Sigit; Subchan
2017-08-01
This paper discussed regarding a model and an optimal control problem of dengue fever transmission. We classified the model as human and vector (mosquito) population classes. For the human population, there are three subclasses, such as susceptible, infected, and resistant classes. Then, for the vector population, we divided it into wiggler, susceptible, and infected vector classes. Thus, the model consists of six dynamic equations. To minimize the number of dengue fever cases, we designed two optimal control variables in the model, the giving of fogging and vaccination. The objective function of this optimal control problem is to minimize the number of infected human population, the number of vector, and the cost of the controlling efforts. By giving the fogging optimally, the number of vector can be minimized. In this case, we considered the giving of vaccination as a control variable because it is one of the efforts that are being developed to reduce the spreading of dengue fever. We used Pontryagin Minimum Principle to solve the optimal control problem. Furthermore, the numerical simulation results are given to show the effect of the optimal control strategies in order to minimize the epidemic of dengue fever.
Ginsberg, H.S.; Butler, M.; Zhioua, E.
2002-01-01
The effects of deer exclusion on northern populations of lone star ticks, Amblyomma americanum, were tested at the Lighthouse Tract, Fire Island, NY, USA, where densities of this species have increased recently. Game fencing was erected to exclude deer from two sites of roughly one ha each, and populations of nymphal and adult A. americanum within were compared with those at control sites outside the exclosures. Percent control of nymphs within vs. outside the exclosures averaged 48.4% in the four years post-treatment, compared to pretreatment values. Percent control varied markedly in different years, suggesting that factors in addition to deer densities had strong effects on population densities of A. americanum. Exclosures of this size did not control adult A. americanum. Effects of deer exclusion in this recently expanded northern population of A. americanum were similar to those that have been reported for southern populations of this species.
26 CFR 1.45D-0 - Table of contents.
Code of Federal Regulations, 2013 CFR
2013-04-01
...) Control. (A) In general. (B) Definition of control. (C) Disregard of control. (7) Financial counseling and... populations. (i) Low-income persons. (A) Definition. (1) In general. (2) Area median family income. (3... targeted populations. (1) In general. (2) Employee. (3) Owner. (4) Derived from. (5) Fair market value of...
26 CFR 1.45D-0 - Table of contents.
Code of Federal Regulations, 2014 CFR
2014-04-01
...) Control. (A) In general. (B) Definition of control. (C) Disregard of control. (7) Financial counseling and... populations. (i) Low-income persons. (A) Definition. (1) In general. (2) Area median family income. (3... targeted populations. (1) In general. (2) Employee. (3) Owner. (4) Derived from. (5) Fair market value of...
26 CFR 1.45D-0 - Table of contents.
Code of Federal Regulations, 2012 CFR
2012-04-01
...) Control. (A) In general. (B) Definition of control. (C) Disregard of control. (7) Financial counseling and... populations. (i) Low-income persons. (A) Definition. (1) In general. (2) Area median family income. (3... targeted populations. (1) In general. (2) Employee. (3) Owner. (4) Derived from. (5) Fair market value of...
USDA-ARS?s Scientific Manuscript database
There are conflicting reports concerning the association of T. gondii infection and schizophrenia. Therefore, we determined such association in a Mexican population of Mestizo ethnicity. Through a case-control study design, 50 schizophrenic patients and 150 control subjects matched by gender, age, r...
Demographic matrix model for informing swallow-wort (Vincetoxicum spp.) biological control
USDA-ARS?s Scientific Manuscript database
Demographic matrix modeling of plant populations can be a powerful tool to identify key life stage transitions that contribute the most to population growth of an invasive plant and hence should be targeted for disruption (weak links) by biological control and/or other control tactics. Therefore, t...
ERIC Educational Resources Information Center
Zeidenstein, George
American attitudes toward foreign aid for population control have changed dramatically since the period following World War II, when birth control assistance was considered too controversial for government funding. With growing national and international concern about population growth and poverty in the developing nations and through the efforts…
García-Jiménez, W L; Fernández-Llario, P; Benítez-Medina, J M; Cerrato, R; Cuesta, J; García-Sánchez, A; Gonçalves, P; Martínez, R; Risco, D; Salguero, F J; Serrano, E; Gómez, L; Hermoso-de-Mendoza, J
2013-07-01
Research on management of bovine tuberculosis (bTB) in wildlife reservoir hosts is crucial for the implementation of effective disease control measures and the generation of practical bTB management recommendations. Among the management methods carried out on wild species to reduce bTB prevalence, the control of population density has been frequently used, with hunting pressure a practical strategy to reduce bTB prevalence. However, despite the number of articles about population density control in different bTB wildlife reservoirs, there is little information regarding the application of such measures on the Eurasian wild boar (Sus scrofa), which is considered the main bTB wildlife reservoir within Mediterranean ecosystems. This study shows the effects of a management measure leading to a radical decrease in wild boar population density at a large hunting estate in Central Spain, in order to assess the evolution of bTB prevalence in both the wild boar population and the sympatric fallow deer population. The evolution of bTB prevalence was monitored in populations of the two wild ungulate species over a 5-year study period (2007-2012). The results showed that bTB prevalence decreased in fallow deer, corresponding to an important reduction in the wild boar population. However, this decrease was not homogeneous: in the last season of study there was an increase in bTB-infected male animals. Moreover, bTB prevalence remained high in the remnant wild boar population. Copyright © 2013 Elsevier B.V. All rights reserved.
Czeizel, A E; Rockenbauer, M; Sørensen, H T; Olsen, J
2000-04-01
To study human teratogenic potential of furazidine treatment during pregnancy. Pair analysis of cases with congenital abnormalities and matched population controls. The Hungarian Case-Control Surveillance of Congenital Abnormalities. 38,151 pregnant women who had newborn infants without any defects (population control group) and 22,865 pregnant women who had newborns or fetuses with congenital abnormalities between 1980 and 1996. In the case group, 157 (0.7%) and in the control group, 254 (0.7%) pregnant women were treated with furazidine. The case-control pair analysis did not indicate a teratogenic potential of furazidine use during the second to third months of gestation, i.e. in the critical period for major congenital abnormalities. Treatment with furazidine during pregnancy did not show teratogenic risk to the fetus.
Cartaxo, Marina F S; Ayres, Constância F J; Weetman, David
2011-09-01
Recife is one of the largest cities in north-eastern Brazil and is endemic for lymphatic filariasis transmitted by Culex quinquefasciatus. Since 2003 a control program has targeted mosquito larvae by elimination of breeding sites and bimonthly application of Bacillus sphaericus. To assess the impact of this program on the local vector population we monitored the genetic diversity and differentiation of Cx. quinquefasciatus using microsatellites and a B. sphaericus-resistance associated mutation (cqm1(REC)) over a 3-year period. We detected a significant but gradual decline in allelic diversity, which, coupled with subtle temporal genetic structure, suggests a major impact of the control program on the vector population. Selection on cqm1(REC) does not appear to be involved with loss of neutral diversity from the population, with no temporal trend in resistant allele frequency and no correlation with microsatellite differentiation. The evidence for short-term genetic drift we detected suggests a low ratio of effective population size: census population size for Cx. quinquefasciatus, perhaps coupled with strong geographically-restricted population structure. Spatial definition of populations will be an important step for success of an expanded vector control program. Copyright © 2011 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.
Evidence-based control of canine rabies: a critical review of population density reduction.
Morters, Michelle K; Restif, Olivier; Hampson, Katie; Cleaveland, Sarah; Wood, James L N; Conlan, Andrew J K
2013-01-01
Control measures for canine rabies include vaccination and reducing population density through culling or sterilization. Despite the evidence that culling fails to control canine rabies, efforts to reduce canine population density continue in many parts of the world. The rationale for reducing population density is that rabies transmission is density-dependent, with disease incidence increasing directly with host density. This may be based, in part, on an incomplete interpretation of historical field data for wildlife, with important implications for disease control in dog populations. Here, we examine historical and more recent field data, in the context of host ecology and epidemic theory, to understand better the role of density in rabies transmission and the reasons why culling fails to control rabies. We conclude that the relationship between host density, disease incidence and other factors is complex and may differ between species. This highlights the difficulties of interpreting field data and the constraints of extrapolations between species, particularly in terms of control policies. We also propose that the complex interactions between dogs and people may render culling of free-roaming dogs ineffective irrespective of the relationship between host density and disease incidence. We conclude that vaccination is the most effective means to control rabies in all species. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.
Goodworth, Adam D.; Wu, Yen-Hsun; Felmlee, Duffy; Dunklebarger, Ellis; Saavedra, Sandra
2016-01-01
Populations with moderate-to-severe motor control impairments often exhibit degraded trunk control and/or lack the ability to sit unassisted. These populations need more research, yet their underdeveloped trunk control complicates identification of neural mechanisms behind their movements. The purpose of this study was to overcome this barrier by developing the first multi-articulated trunk support system to identify visual, vestibular, and proprioception contributions to posture in populations lacking independent sitting. The system provided external stability at a user-specific level on the trunk, so that body segments above the level of support required active posture control. The system included a tilting surface (controlled via servomotor) as a stimulus to investigate sensory contributions to postural responses. Frequency response and coherence functions between the surface tilt and trunk support were used to characterize system dynamics and indicated that surface tilts were accurately transmitted up to 5Hz. Feasibility of collecting kinematic data in participants lacking independent sitting was demonstrated in two populations: two typically developing infants, ~2-8 months, in a longitudinal study (8 sessions each) and four children with moderate-to-severe cerebral palsy (GMFCS III-V). Adaptability in the system was assessed by testing 16 adults (ages 18-63). Kinematic responses to continuous pseudorandom surface tilts were evaluated across 0.046–2Hz and qualitative feedback indicated that the trunk support and stimulus were comfortable for all subjects. Concepts underlying the system enable both research for, and rehabilitation in, populations lacking independent sitting. PMID:27046877
Popullution: A Position Paper on Population.
ERIC Educational Resources Information Center
Durner, Mary Beth
This position paper presents an interdisciplinary approach to the study of population. Six main sections are included in the paper: Introduction, The Growth of the Human Population, The Psychological Effects of Population Growth, Overpopulated America, Myths Concerning Population Growth and Control, and Population Education. Section 1, an…
Optimal control applied to a model for species augmentation.
Bodine, Erin N; Gross, Louis J; Lenhart, Suzanne
2008-10-01
Species augmentation is a method of reducing species loss via augmenting declining or threatened populations with individuals from captive-bred or stable, wild populations. In this paper, we develop a differential equations model and optimal control formulation for a continuous time augmentation of a general declining population. We find a characterization for the optimal control and show numerical results for scenarios of different illustrative parameter sets. The numerical results provide considerably more detail about the exact dynamics of optimal augmentation than can be readily intuited. The work and results presented in this paper are a first step toward building a general theory of population augmentation, which accounts for the complexities inherent in many conservation biology applications.
Optimal management of non-Markovian biological populations
Williams, B.K.
2007-01-01
Wildlife populations typically are described by Markovian models, with population dynamics influenced at each point in time by current but not previous population levels. Considerable work has been done on identifying optimal management strategies under the Markovian assumption. In this paper we generalize this work to non-Markovian systems, for which population responses to management are influenced by lagged as well as current status and/or controls. We use the maximum principle of optimal control theory to derive conditions for the optimal management such a system, and illustrate the effects of lags on the structure of optimal habitat strategies for a predator-prey system.
Sandhya, P; Danda, Sumita; Danda, Debashish; Lonarkar, Shraddha; Luke, Shana S; Sinha, Shanta; Joseph, George
2013-04-01
Tumour necrosis factor-alpha (TNF-α)- 308 promoter gene polymorphism has been shown to be associated with several autoimmune disorders and infections such as tuberculosis. There is no study on TNF-α gene polymorphism in Takayasu's arteritis (TA) till date. We aimed to study this polymorphism in TA, a granulomatous vasculitis, probably triggered by Mycobacterium tuberculosis. TNF-α - 308 gene polymorphism was studied in 34 patients with TA and 39 healthy controls recruited from Christian Medical College, India. PCR was done followed by enzyme digestion. G and A polymorphisms were analysed. Occurrence of alleles in the disease group was compared with controls as well as with historical controls. GG allele was most frequent in TA and in controls. GA allele was detected in four controls but only in one patient who was the oldest in the study group. AA polymorphism was detected in one control but not in TA. When compared with controls from other populations, it was found that our allelic frequency was similar to that in Japan as well as from USA with mixed population. However, predominantly Caucasian population studied from Netherlands, Germany and England, where TA is rare, had a higher frequency of A allele as compared to our controls. Our preliminary results indicated that G allele at TNF-α - 308 was more common in TA patients and controls similar to that in other Indian as well as Japanese population. Compared to the western population, A allele was relatively less common in our study subjects.
How to control chaotic behaviour and population size with proportional feedback
NASA Astrophysics Data System (ADS)
Liz, Eduardo
2010-01-01
We study the control of chaos in one-dimensional discrete maps as they often occur in modelling population dynamics. For managing the population, we seek to suppress any possible chaotic behavior, leading the system to a stable equilibrium. In this Letter, we make a rigorous analysis of the proportional feedback method under certain conditions fulfilled by a wide family of maps. We show that it is possible to stabilize the chaotic dynamics towards a globally stable positive equilibrium, that can be chosen among a broad range of possible values. In particular, the size of the population can be enhanced by control in form of population reduction. This paradoxical phenomenon is known as the hydra effect, and it has important implications in the design of strategies in such areas as fishing, pest management, and conservation biology.
Learning-by-catching: uncertain invasive-species populations and the value of information.
D'Evelyn, Sean T; Tarui, Nori; Burnett, Kimberly; Roumasset, James A
2008-12-01
This paper develops a model of invasive species control when the species' population size is unknown. In the face of an uncertain population size, a resource manager's species-control efforts provide two potential benefits: (1) a direct benefit of possibly reducing the population of invasive species, and (2) an indirect benefit of information acquisition (due to learning about the population size, which reduces uncertainty). We provide a methodology that takes into account both of these benefits, and show how optimal management decisions are altered in the presence of the indirect benefit of learning. We then apply this methodology to the case of controlling the Brown Treesnake (Boiga irregularis) on the island of Saipan. We find that the indirect benefit--the value of information to reduce uncertainty--is likely to be quite large.
Robert R. Pattison; Carla M. D' Antonio; Tom L. Dudley; Kip K. Allander; Benjamin Rice
2010-01-01
The success of biological control programs is rarely assessed beyond population level impacts on the target organism. The question of whether a biological control agent can either partially or completely restore ecosystem services independent of population level control is therefore still open to discussion. Using observational and experimental approaches, we...
ERIC Educational Resources Information Center
Yost, Thomas E.
The purpose of this study was to obtain, measure, and evaluate the attitudes of postsecondary students on domestic population issues in order to determine the extent of support for a national government-controlled population stabilization program. A total of 125 students enrolled in either the American government or general sociology course at the…
Stephen W. Fraedrich; L. David Dwinell
2005-01-01
Dazomet, metam sodium, and oxamyl were evaluated for nematode control and production of loblolly pine seedlings in a field infested by a Longidorus sp. Fumigation with dazomet or metam sodium reduced population densities of longidorus to nondetectable levels early in the growing season but population densities subsequently increases to levels found in untreated control...
Waltmann, Andreea; Koepfli, Cristian; Tessier, Natacha; Karl, Stephan; Fola, Abebe; Darcy, Andrew W.; Wini, Lyndes; Harrison, G. L. Abby; Barnadas, Céline; Jennison, Charlie; Karunajeewa, Harin; Boyd, Sarah; Whittaker, Maxine; Kazura, James; Bahlo, Melanie; Mueller, Ivo
2018-01-01
The human malaria parasite Plasmodium vivax is more resistant to malaria control strategies than Plasmodium falciparum, and maintains high genetic diversity even when transmission is low. To investigate whether declining P. vivax transmission leads to increasing population structure that would facilitate elimination, we genotyped samples from across the Southwest Pacific region, which experiences an eastward decline in malaria transmission, as well as samples from two time points at one site (Tetere, Solomon Islands) during intensified malaria control. Analysis of 887 P. vivax microsatellite haplotypes from hyperendemic Papua New Guinea (PNG, n = 443), meso-hyperendemic Solomon Islands (n = 420), and hypoendemic Vanuatu (n = 24) revealed increasing population structure and multilocus linkage disequilibrium yet a modest decline in diversity as transmission decreases over space and time. In Solomon Islands, which has had sustained control efforts for 20 years, and Vanuatu, which has experienced sustained low transmission for many years, significant population structure was observed at different spatial scales. We conclude that control efforts will eventually impact P. vivax population structure and with sustained pressure, populations may eventually fragment into a limited number of clustered foci that could be targeted for elimination. PMID:29373596
Waltmann, Andreea; Koepfli, Cristian; Tessier, Natacha; Karl, Stephan; Fola, Abebe; Darcy, Andrew W; Wini, Lyndes; Harrison, G L Abby; Barnadas, Céline; Jennison, Charlie; Karunajeewa, Harin; Boyd, Sarah; Whittaker, Maxine; Kazura, James; Bahlo, Melanie; Mueller, Ivo; Barry, Alyssa E
2018-01-01
The human malaria parasite Plasmodium vivax is more resistant to malaria control strategies than Plasmodium falciparum, and maintains high genetic diversity even when transmission is low. To investigate whether declining P. vivax transmission leads to increasing population structure that would facilitate elimination, we genotyped samples from across the Southwest Pacific region, which experiences an eastward decline in malaria transmission, as well as samples from two time points at one site (Tetere, Solomon Islands) during intensified malaria control. Analysis of 887 P. vivax microsatellite haplotypes from hyperendemic Papua New Guinea (PNG, n = 443), meso-hyperendemic Solomon Islands (n = 420), and hypoendemic Vanuatu (n = 24) revealed increasing population structure and multilocus linkage disequilibrium yet a modest decline in diversity as transmission decreases over space and time. In Solomon Islands, which has had sustained control efforts for 20 years, and Vanuatu, which has experienced sustained low transmission for many years, significant population structure was observed at different spatial scales. We conclude that control efforts will eventually impact P. vivax population structure and with sustained pressure, populations may eventually fragment into a limited number of clustered foci that could be targeted for elimination.
Herbivory, Predation, and Biological Control.
ERIC Educational Resources Information Center
Murphy, Terence M.; And Others
1992-01-01
Authors describe a set of controlled ecosystems that can be used to demonstrate the effects of herbivory on the health and growth of a plant population and of predation on the growth of a primary consumer population. The system also shows the effectiveness of biological pest control measures in a dramatic way. The construction of the ecosystems is…
The use and manipulation of insect reproductive molecules for controlling insect populations
USDA-ARS?s Scientific Manuscript database
The use and manipulation of insect reproductive molecules, and the genes that encode them, provides a variety of methods to control insect fertility and thus a means of population control for insect pests. Towards this end, we first studied the yolk polypeptide gene from the caribfly, Anastrepha su...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-30
... reduce or control overabundant resident Canada geese populations. Increasing the daily bag limit from 8 to 15 geese may help both States reduce or control existing high populations of resident Canada geese... our Migratory Bird Surveys and assigned control number 1018-0023 (expires 4/30/2014). This information...
Biological control agents elevate hantavirus by subsidizing deer mouse populations.
Pearson, Dean E; Callaway, Ragan M
2006-04-01
Biological control of exotic invasive plants using exotic insects is practiced under the assumption that biological control agents are safe if they do not directly attack non-target species. We tested this assumption by evaluating the potential for two host-specific biological control agents (Urophora spp.), widely established in North America for spotted knapweed (Centaurea maculosa) control, to indirectly elevate Sin Nombre hantavirus by providing food subsidies to populations of deer mice (Peromyscus maniculatus), the primary reservoir for the virus. We show that seropositive deer mice (mice testing positive for hantavirus) were over three times more abundant in the presence of the biocontrol food subsidy. Elevating densities of seropositive mice may increase risk of hantavirus infection in humans and significantly alter hantavirus ecology. Host specificity alone does not ensure safe biological control. To minimize indirect risks to non-target species, biological control agents must suppress pest populations enough to reduce their own numbers.
Yi, Stella S; Tabaei, Bahman P; Angell, Sonia Y; Rapin, Anne; Buck, Michael D; Pagano, William G; Maselli, Frank J; Simmons, Alvaro; Chamany, Shadi
2015-03-01
Hypertension is a leading risk factor for cardiovascular disease. Although control rates have improved over time, racial/ethnic disparities in hypertension control persist. Self-blood pressure monitoring, by itself, has been shown to be an effective tool in predominantly white populations, but less studied in minority, urban communities. These types of minimally intensive approaches are important to test in all populations, especially those experiencing related health disparities, for broad implementation with limited resources. The New York City Health Department in partnership with community clinic networks implemented a randomized clinical trial (n=900, 450 per arm) to investigate the effectiveness of self-blood pressure monitoring in medically underserved and largely black and Hispanic participants. Intervention participants received a home blood pressure monitor and training on use, whereas control participants received usual care. After 9 months, systolic blood pressure decreased (intervention, 14.7 mm Hg; control, 14.1 mm Hg; P=0.70). Similar results were observed when incorporating longitudinal data and calculating a mean slope over time. Control was achieved in 38.9% of intervention and 39.1% of control participants at the end of follow-up; the time-to-event experience of achieving blood pressure control in the intervention versus control groups were not different from each other (logrank P value =0.91). Self-blood pressure monitoring was not shown to improve control over usual care in this largely minority, urban population. The patient population in this study, which included a high proportion of Hispanics and uninsured persons, is understudied. Results indicate these groups may have additional meaningful barriers to achieving blood pressure control beyond access to the monitor itself. http://clinicaltrials.gov. Unique Identifier: NCT01123577. © 2015 American Heart Association, Inc.
Normandin, Sebastian; Valles, Sean A
2015-06-01
Continuing historical narratives of the early twentieth century nexus of conservationism, eugenics, and nativism (exemplified by Madison Grant), this paper traces the history of the contemporary US anti-immigration movement's roots in environmentalism and global population control activism, through an exploration of the thoughts and activities of the activist, John Tanton, who has been called "the most influential unknown man in America." We explore the "neo-Malthusian" ideas that sparked a seminal moment for population control advocacy in the late 1960s and early 1970s, leading to the creation of Zero Population Growth (ZPG). After rising to the presidency of ZPG, Tanton, and ZPG spun off the Federation for American Immigration Reform. After leaving ZPG's leadership, Tanton created additional anti-immigration advocacy groups and built up connections with existing organizations such as the Pioneer Fund. We trace Tanton's increasingly radical conservative network of anti-immigration advocates, conservationists, and population control activists to the present day. Tanton's archived papers illustrate, among other things, his interactions with collaborators such as ecologist Garrett Hardin (author of the famous "Tragedy of the Commons") and his documented interest in reviving eugenics. We contend that this history of Tanton's network provides key insights into understanding how there came to be an overlap between the ideologies and activist communities of immigration restrictionism, population control, conservationism and eugenics. Copyright © 2015 Elsevier Ltd. All rights reserved.
Tsetse Control and Gambian Sleeping Sickness; Implications for Control Strategy.
Tirados, Inaki; Esterhuizen, Johan; Kovacic, Vanja; Mangwiro, T N Clement; Vale, Glyn A; Hastings, Ian; Solano, Philippe; Lehane, Michael J; Torr, Steve J
2015-01-01
Gambian sleeping sickness (human African trypanosomiasis, HAT) outbreaks are brought under control by case detection and treatment although it is recognised that this typically only reaches about 75% of the population. Vector control is capable of completely interrupting HAT transmission but is not used because it is considered too expensive and difficult to organise in resource-poor settings. We conducted a full scale field trial of a refined vector control technology to determine its utility in control of Gambian HAT. The major vector of Gambian HAT is the tsetse fly Glossina fuscipes which lives in the humid zone immediately adjacent to water bodies. From a series of preliminary trials we determined the number of tiny targets required to reduce G. fuscipes populations by more than 90%. Using these data for model calibration we predicted we needed a target density of 20 per linear km of river in riverine savannah to achieve >90% tsetse control. We then carried out a full scale, 500 km2 field trial covering two HAT foci in Northern Uganda to determine the efficacy of tiny targets (overall target density 5.7/km2). In 12 months, tsetse populations declined by more than 90%. As a guide we used a published HAT transmission model and calculated that a 72% reduction in tsetse population is required to stop transmission in those settings. The Ugandan census suggests population density in the HAT foci is approximately 500 per km2. The estimated cost for a single round of active case detection (excluding treatment), covering 80% of the population, is US$433,333 (WHO figures). One year of vector control organised within the country, which can completely stop HAT transmission, would cost US$42,700. The case for adding this method of vector control to case detection and treatment is strong. We outline how such a component could be organised.
Tsetse Control and Gambian Sleeping Sickness; Implications for Control Strategy
Kovacic, Vanja; Mangwiro, T. N. Clement; Vale, Glyn A.; Hastings, Ian; Solano, Philippe; Lehane, Michael J.; Torr, Steve J.
2015-01-01
Background Gambian sleeping sickness (human African trypanosomiasis, HAT) outbreaks are brought under control by case detection and treatment although it is recognised that this typically only reaches about 75% of the population. Vector control is capable of completely interrupting HAT transmission but is not used because it is considered too expensive and difficult to organise in resource-poor settings. We conducted a full scale field trial of a refined vector control technology to determine its utility in control of Gambian HAT. Methods and Findings The major vector of Gambian HAT is the tsetse fly Glossina fuscipes which lives in the humid zone immediately adjacent to water bodies. From a series of preliminary trials we determined the number of tiny targets required to reduce G. fuscipes populations by more than 90%. Using these data for model calibration we predicted we needed a target density of 20 per linear km of river in riverine savannah to achieve >90% tsetse control. We then carried out a full scale, 500 km2 field trial covering two HAT foci in Northern Uganda to determine the efficacy of tiny targets (overall target density 5.7/km2). In 12 months, tsetse populations declined by more than 90%. As a guide we used a published HAT transmission model and calculated that a 72% reduction in tsetse population is required to stop transmission in those settings. Interpretation The Ugandan census suggests population density in the HAT foci is approximately 500 per km2. The estimated cost for a single round of active case detection (excluding treatment), covering 80% of the population, is US$433,333 (WHO figures). One year of vector control organised within the country, which can completely stop HAT transmission, would cost US$42,700. The case for adding this method of vector control to case detection and treatment is strong. We outline how such a component could be organised. PMID:26267814
Assessing different measures of population-level vaccine protection using a case-control study.
Ali, Mohammad; You, Young Ae; Kanungo, Suman; Manna, Byomkesh; Deen, Jacqueline L; Lopez, Anna Lena; Wierzba, Thomas F; Bhattacharya, Sujit K; Sur, Dipika; Clemens, John D
2015-11-27
Case-control studies have not been examined for their utility in assessing population-level vaccine protection in individually randomized trials. We used the data of a randomized, placebo-controlled trial of a cholera vaccine to compare the results of case-control analyses with those of cohort analyses. Cases of cholera were selected from the trial population followed for three years following dosing. For each case, we selected 4 age-matched controls who had not developed cholera. For each case and control, GIS was used to calculate vaccine coverage of individuals in a surrounding "virtual" cluster. Specific selection strategies were used to evaluate the vaccine protective effects. 66,900 out of 108,389 individuals received two doses of the assigned regimen. For direct protection among subjects in low vaccine coverage clusters, we observed 78% (95% CI: 47-91%) protection in a cohort analysis and 84% (95% CI: 60-94%) in case-control analysis after adjusting for confounding factors. Using our GIS-based approach, estimated indirect protection was 52% (95% CI: 10-74%) in cohort and 76% (95% CI: 47-89%) in case control analysis. Estimates of total and overall effectiveness were similar for cohort and case-control analyses. The findings show that case-control analyses of individually randomized vaccine trials may be used to evaluate direct as well as population-level vaccine protection. Copyright © 2015. Published by Elsevier Ltd.
The effectiveness of tobacco control policies on vulnerable populations in the USA: a review.
Vijayaraghavan, Maya; Schroeder, Steven A; Kushel, Margot
2016-09-22
Despite population-wide efforts to reduce tobacco use, low-income populations in the USA have much higher rates of tobacco use compared with the general population. The principal components of tobacco control policies in the USA include cigarette taxes, clean indoor air laws and comprehensive interventions to increase access to tobacco cessation services. In this review, we describe the effectiveness of these policies and interventions in reducing tobacco use among vulnerable populations, focusing on persons with mental health disorders and substance use disorders, persons who have experienced incarceration or homelessness, and low-income tenants of public housing. We discuss the challenges that evolving tobacco and nicotine products pose to tobacco control efforts. We conclude by highlighting the clinical implications of treating tobacco dependence in healthcare settings that serve vulnerable populations. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Compensatory mortality in mule deer populations: Technical progress report. [Odocoileus hemionus
DOE Office of Scientific and Technical Information (OSTI.GOV)
White, G.C.
1987-07-15
The hypothesis of compensatory mortality is critical to understanding population dynamics of wildlife species. This research tested for compensatory mortality in the juvenile (fawn) portion of a mule deer population. In the fall of 1986, 60 fawns were telemetered on both the control and treatment sites of the Little Hills study area. Thirteen adult females also were telemetered which, together with 31 telemetered adults already present, brought the total instrumented population to 164 at the onset of winter. Experimental manipulation to test for compensation in the population was successful, with 18% of the population on the treatment area (328 animals)more » removed. Line transect estimates of deer groups/ha were 0.12 +- 0.030 (D +- SE) for the control area and 0.14 +- 0.028 for the treatment area, giving 1727 individuals on the control area and 1490 on the treatment area. Thus the number of deer was measurably decreased on the treatment area by the removal operation.« less
Book examines fertility and politics in Egypt, India, Kenya, and Mexico.
1998-09-01
The politics of fertility control refers to the role of the state in regulating individual behavior. It is about the influence of academics and intellectuals, the motivations of officials and bureaucrats, and the interests of international donors. The politics of fertility control is also about the control which one class or ethnic group exerts over another, and the gender relations within and beyond the household. The Population Council's book, "Do Population Policies Matter? Fertility and Politics in Egypt, India, Kenya, and Mexico," examines what makes the population policies of those four countries either succeed or fail. The analyses show how and why the creation, implementation, and effectiveness of population policies vary over time both within and between countries. Furthermore, the authors demonstrate that effective population policies require political commitment and courage, broad support, adequate funding, good design and management, and a sound concept. The volume's case studies explore population policy-making from both historical and contemporary perspectives in the individual country contexts.
Dalager-Pedersen, Michael; Søgaard, Mette; Schønheyder, Henrik Carl; Nielsen, Henrik; Thomsen, Reimar Wernich
2014-04-01
Infections may trigger acute cardiovascular events, but the risk after community-acquired bacteremia is unknown. We assessed the risk for acute myocardial infarction and ischemic stroke within 1 year of community-acquired bacteremia. This population-based cohort study was conducted in Northern Denmark. We included 4389 hospitalized medical patients with positive blood cultures obtained on the day of admission. Patients hospitalized with bacteremia were matched with up to 10 general population controls and up to 5 acutely admitted nonbacteremic controls, matched on age, sex, and calendar time. All incident events of myocardial infarction and stroke during the following 365 days were ascertained from population-based healthcare databases. Multivariable regression analyses were used to assess relative risks with 95% confidence intervals (CIs) for myocardial infarction and stroke among bacteremia patients and their controls. The risk for myocardial infarction or stroke was greatly increased within 30 days of community-acquired bacteremia: 3.6% versus 0.2% among population controls (adjusted relative risk, 20.86; 95% CI, 15.38-28.29) and 1.7% among hospitalized controls (adjusted relative risk, 2.18; 95% CI, 1.80-2.65). The risks for myocardial infarction or stroke remained modestly increased from 31 to 180 days after bacteremia in comparison with population controls (adjusted hazard ratio, 1.64; 95% CI, 1.18-2.27), but not versus hospitalized controls (adjusted hazard ratio, 0.95; 95% CI, 0.69-1.32). No differences in cardiovascular risk were seen after >6 months. Increased 30-day risks were consistently found for a variety of etiologic agents and infectious foci. Community-acquired bacteremia is associated with increased short-term risk of myocardial infarction and stroke.
Erickson, Priscilla A.; Glazer, Andrew M.; Cleves, Phillip A.; Smith, Alyson S.; Miller, Craig T.
2014-01-01
In convergent evolution, similar phenotypes evolve repeatedly in independent populations, often reflecting adaptation to similar environments. Understanding whether convergent evolution proceeds via similar or different genetic and developmental mechanisms offers insight towards the repeatability and predictability of evolution. Oceanic populations of threespine stickleback fish, Gasterosteus aculeatus, have repeatedly colonized countless freshwater lakes and streams, where new diets lead to morphological adaptations related to feeding. Here, we show that heritable increases in branchial bone length have convergently evolved in two independently derived freshwater stickleback populations. In both populations, an increased bone growth rate in juveniles underlies the convergent adult phenotype, and one population also has a longer cartilage template. Using F2 crosses from these two freshwater populations, we show that two quantitative trait loci (QTL) control branchial bone length at distinct points in development. In both populations, a QTL on chromosome 21 controls bone length throughout juvenile development, and a QTL on chromosome 4 controls bone length only in adults. In addition to these similar developmental profiles, these QTL show similar chromosomal locations in both populations. Our results suggest that sticklebacks have convergently evolved longer branchial bones using similar genetic and developmental programmes in two independently derived populations. PMID:24966315
2014-01-01
Background Indoor Residual Spraying (IRS) and Long-Lasting Insecticidal nets (LLINs) are major malaria vector control tools in Ethiopia. However, recent reports from different parts of the country showed that populations of Anopheles arabiensis, the principal malaria vector, have developed resistance to most families of insecticides recommended for public health use which may compromise the efficacy of both of these key vector control interventions. Thus, this study evaluated the efficacy of DDT IRS and LLINs against resistant populations of An. arabiensis using experimental huts in Asendabo area, southwestern Ethiopia. Methods The susceptibility status of populations of An. arabiensis was assessed using WHO test kits to DDT, deltamethrin, malathion, lambda-cyhalothrin, fenitrothion and bendiocarb. The efficacy of LLIN (PermaNet® 2.0), was evaluated using the WHO cone bioassay. Moreover, the effect of the observed resistance against malaria vector control interventions (DDT IRS and LLINs) were assessed using experimental huts. Results The findings of this study revealed that populations of An. arabiensis were resistant to DDT, deltamethrin, lambda-cyhalothrin and malathion with mortality rates of 1.3%, 18.8%, 36.3% and 72.5%, respectively but susceptible to fenitrothion and bendiocarb with mortality rates of 98.81% and 97.5%, respectively. The bio-efficacy test of LLIN (PermaNet® 2.0) against An. arabiensis revealed that the mosquito population showed moderate knockdown (64%) and mortality (78%). Moreover, mosquito mortalities in DDT sprayed huts and in huts with LLINs were not significantly different (p > 0.05) from their respective controls. Conclusion The evaluation of the efficacy of DDT IRS and LLINs using experimental huts showed that both vector control tools had only low to moderate efficacy against An. arabiensis populations from Ethiopia. Despite DDT being replaced by carbamates for IRS, the low efficacy of LLINs against the resistant population of An. arabiensis is still a problem. Thus, there is a need for alternative vector control tools and implementation of appropriate insecticide resistance management strategies as part of integrated vector management by the national malaria control program. PMID:24678605
Singleterry, Will L; Henderson, Harold; Cruse, Julius M
2012-02-01
In this present investigation, flow cytometry was utilized to evaluate 13 healthy controls and 31 HIV-1 infected patients who had advanced to the AIDS stage of infection (CD4 count below 200 cells/mm(3)), for the expression of CD161 on CD3(+) double negative (DN) (CD3(+)CD4(-)CD8(-)) T cells, CD4(+) T cells, CD8(+) T cells and γδ T cells. The observed depletion of CD161(+) T cells from peripheral circulation was due primarily to the loss of CD4(+)CD161(+) T cells; as these cells represented 8.67±0.74% of the total healthy control peripheral T cell population, while the CD4(+)CD161(+) T cells of the AIDS group represented only 3.35±0.41% (p=<0.0001) of the total peripheral T cell population. We have also shown here that the DN T cell population was more than doubled in the AIDS group, with the DN T cell population expanding from 3.29±0.45% of the healthy control peripheral T cell population to 8.64±1.16% (p=0.0001) of the AIDS group peripheral T cell population. By evaluating the expression of CD161 on the surface of the DN T cells we showed that within the healthy control group, 47.4±4.99% of the DN T cells were positive for the expression of CD161, while only 26.4±3.54% (p=0.002) of the AIDS group's DN T cells expressed CD161. Despite CD161 expression being halved on the DN T cells of the AIDS group, when we compared the total peripheral T cell percentage of CD161(+) DN T cells between the healthy control group and the AIDS group, there was no statistical difference. Even though only 26.4% DN T cells within the AIDS group were positive for CD161(+), the overall DN T cell population had expanded to such an extent that there was no statistical difference between the groups with regard to CD161(+) DN T cells as a percentage of the total peripheral T cell population. Furthermore, we showed that within the DN T cell population, there was an approximate 2:1 ratio of γδ to αβ T cells, and this ratio was maintained in both the healthy control group and the AIDS group. While evaluating γδ T cells we also discovered that CD8(+) γδ T cells were expanded from 0.62±.09% of the healthy control peripheral T cell population to 5.01±.88% (p=<0.0001) of the peripheral T cell population of the AIDS group; and that this population of CD8(+) γδ T cells underwent the same reduction in percentage of cells expressing CD161(+), further demonstrated that the phenomenon of CD161(+) percentage reduction and compensatory increase in total cell population was affecting the entire circulating γδ T cell population. Copyright © 2011 Elsevier Inc. All rights reserved.
Population ecology of feral horses in an era of fertility control management
Ransom, J.I.
2012-01-01
Management of wildlife often requires intervention to regulate growth of populations that would otherwise become overabundant. Controlling fecundity using contraceptives has become an increasingly popular tool for attempting to manage locally overabundant wildlife species, but the population-level effects of such applications are largely unknown. Contraceptive treatments can produce unexpected feedbacks that act on births, survival, immigration, and emigration. Such feedbacks may considerably influence our ability to regulate populations using fertility control. I followed feral horses (Equus caballus) in three intensively managed populations to assess longitudinal treatment effects on demography. The transient contraceptive porcine zona pellucida (PZP) produced longer duration of infertility than intended. Repeated PZP vaccinations of females extended the duration of infertility far beyond the targeted management period, with time to first post-treatment parturition increasing 411days for every annual inoculation received. When these animals did conceive and give birth, parturition was later in the year and temporally asynchronous with forage abundance. An average of 30% (range=11–77%) of females were contracepted annually during the treatment period in all three populations and apparent annual population growth rate was 4–9% lower in the post-treatment years as compared to pretreatment years. Population growth was positive, however, and increased steadily every year that a management removal did not occur. The observed number of births was 33% fewer than the expected number of births, based on number of treated females, individual efficacy of treatment, and number of untreated females and their age-specific fecundity rates. Only half of this difference was explained by the apparent residual effect of treatment. Birth rate in the youngest untreated females (age 2–5 years old) was reduced in years when their conspecifics were treated, enhancing the effects of treatment at the population-level. This was partially offset by increased survival in adults, including a 300% increase in presence of horses ≥20 years old during the post-treatment period. In closed populations of feral horses, the positive feedbacks appear to outweigh the negative feedbacks and generate a larger contraceptive effect than the sum of individual treatments. The role of fertility control is uncertain for open populations of many wildlife species, with broad consensus across a synthesis of research that negative feedbacks on fertility control performance are occurring, and in many cases increased survival and increased immigration can compensate entirely for the reduction in births attributed to treatment. Understanding species‘ life-history strategies, biology, behavioral ecology, and ecological context is critical to developing realistic expectations of regulating wildlife populations using fertility control.
Mendes-de-Almeida, Flavya; Remy, Gabriella L; Gershony, Liza C; Rodrigues, Daniela P; Chame, Marcia; Labarthe, Norma V
2011-06-01
The size of urban cat colonies is limited only by the availability of food and shelter; therefore, their population growth challenges all known population control programs. To test a new population control method, a free-roaming feral cat colony at the Zoological Park in the city of Rio de Janeiro was studied, beginning in 2001. The novel method consisted of performing a hysterectomy on all captured female cats over 6 months of age. To estimate the size of the colony and compare population from year to year, a method of capture-mark-release-recapture was used. The aim was to capture as many individuals as possible, including cats of all ages and gender to estimate numbers of cats in all population categories. Results indicated that the feral cat population remained constant from 2001 to 2004. From 2004 to 2008, the hysterectomy program and population estimates were performed every other year (2006 and 2008). The population was estimated to be 40 cats in 2004, 26 in 2006, and 17 cats in 2008. Although pathogens tend to infect more individuals as the population grows older and maintains natural behavior, these results show that free-roaming feral cat colonies could have their population controlled by a biannual program that focuses on hysterectomy of sexually active female cats. Copyright © 2011 ISFM and AAFP. Published by Elsevier Ltd. All rights reserved.
Wolbachia-induced cytoplasmic incompatibility as a means for insect pest population control.
Zabalou, Sofia; Riegler, Markus; Theodorakopoulou, Marianna; Stauffer, Christian; Savakis, Charalambos; Bourtzis, Kostas
2004-10-19
Biological control is the purposeful introduction of parasites, predators, and pathogens to reduce or suppress pest populations. Wolbachia are inherited bacteria of arthropods that have recently attracted attention for their potential as new biocontrol agents. Wolbachia manipulate host reproduction by using several strategies, one of which is cytoplasmic incompatibility (CI) [Stouthamer, R., Breeuwer, J. A. J. & Hurst, G. D. D. (1999) Annu. Rev. Microbiol. 53, 71-102]. We established Wolbachia-infected lines of the medfly Ceratitis capitata using the infected cherry fruit fly Rhagoletis cerasi as donor. Wolbachia induced complete CI in the novel host. Laboratory cage populations were completely suppressed by single releases of infected males, suggesting that Wolbachia-induced CI could be used as a novel environmentally friendly tool for the control of medfly populations. The results also encourage the introduction of Wolbachia into pest and vector species of economic and hygenic relevance to suppress or modify natural populations.
Wolbachia-induced cytoplasmic incompatibility as a means for insect pest population control
Zabalou, Sofia; Riegler, Markus; Theodorakopoulou, Marianna; Stauffer, Christian; Savakis, Charalambos; Bourtzis, Kostas
2004-01-01
Biological control is the purposeful introduction of parasites, predators, and pathogens to reduce or suppress pest populations. Wolbachia are inherited bacteria of arthropods that have recently attracted attention for their potential as new biocontrol agents. Wolbachia manipulate host reproduction by using several strategies, one of which is cytoplasmic incompatibility (CI) [Stouthamer, R., Breeuwer, J. A. J. & Hurst, G. D. D. (1999) Annu. Rev. Microbiol. 53, 71–102]. We established Wolbachia-infected lines of the medfly Ceratitis capitata using the infected cherry fruit fly Rhagoletis cerasi as donor. Wolbachia induced complete CI in the novel host. Laboratory cage populations were completely suppressed by single releases of infected males, suggesting that Wolbachia-induced CI could be used as a novel environmentally friendly tool for the control of medfly populations. The results also encourage the introduction of Wolbachia into pest and vector species of economic and hygenic relevance to suppress or modify natural populations. PMID:15469918
Laser pulses for coherent xuv Raman excitation
NASA Astrophysics Data System (ADS)
Greenman, Loren; Koch, Christiane P.; Whaley, K. Birgitta
2015-07-01
We combine multichannel electronic structure theory with quantum optimal control to derive femtosecond-time-scale Raman pulse sequences that coherently populate a valence excited state. For a neon atom, Raman target populations of up to 13% are obtained. Superpositions of the ground and valence Raman states with a controllable relative phase are found to be reachable with up to 4.5% population and arbitrary phase control facilitated by the pump pulse carrier-envelope phase. Analysis of the optimized pulse structure reveals a sequential mechanism in which the valence excitation is reached via a fast (femtosecond) population transfer through an intermediate resonance state in the continuum rather than avoiding intermediate-state population with simultaneous or counterintuitive (stimulated Raman adiabatic passage) pulse sequences. Our results open a route to coupling valence excitations and core-hole excitations in molecules and aggregates that locally address specific atoms and represent an initial step towards realization of multidimensional spectroscopy in the xuv and x-ray regimes.
Septic tank additive impacts on microbial populations.
Pradhan, S; Hoover, M T; Clark, G H; Gumpertz, M; Wollum, A G; Cobb, C; Strock, J
2008-01-01
Environmental health specialists, other onsite wastewater professionals, scientists, and homeowners have questioned the effectiveness of septic tank additives. This paper describes an independent, third-party, field scale, research study of the effects of three liquid bacterial septic tank additives and a control (no additive) on septic tank microbial populations. Microbial populations were measured quarterly in a field study for 12 months in 48 full-size, functioning septic tanks. Bacterial populations in the 48 septic tanks were statistically analyzed with a mixed linear model. Additive effects were assessed for three septic tank maintenance levels (low, intermediate, and high). Dunnett's t-test for tank bacteria (alpha = .05) indicated that none of the treatments were significantly different, overall, from the control at the statistical level tested. In addition, the additives had no significant effects on septic tank bacterial populations at any of the septic tank maintenance levels. Additional controlled, field-based research iswarranted, however, to address additional additives and experimental conditions.
Bliman, Pierre-Alexandre; Aronna, M Soledad; Coelho, Flávio C; da Silva, Moacyr A H B
2018-04-01
The control of the spread of dengue fever by introduction of the intracellular parasitic bacterium Wolbachia in populations of the vector Aedes aegypti, is presently one of the most promising tools for eliminating dengue, in the absence of an efficient vaccine. The success of this operation requires locally careful planning to determine the adequate number of individuals carrying the Wolbachia parasite that need to be introduced into the natural population. The introduced mosquitoes are expected to eventually replace the Wolbachia-free population and guarantee permanent protection against the transmission of dengue to human. In this study, we propose and analyze a model describing the fundamental aspects of the competition between mosquitoes carrying Wolbachia and mosquitoes free of the parasite. We then use feedback control techniques to devise an introduction protocol that is proved to guarantee that the population converges to a stable equilibrium where the totality of mosquitoes carry Wolbachia.
The Importance of Social Support on Glycemic Control in Low-Income Latinos with Type 2 Diabetes
ERIC Educational Resources Information Center
Rotberg, Britt; Junqueira, Yasmine; Gosdin, Lucas; Mejia, Roberto; Umpierrez, Guillermo E.
2016-01-01
Background: The U.S. Latino population exhibits poorer glycemic control than the white population, leading to more frequent health complications and greater disease severity. Social support has been shown a significant factor in health and well-being. Purpose: To determine the association between glycemic control and social support in patients…
Dog population management for the control of human echinococcosis.
Kachani, Malika; Heath, David
2014-11-01
Cystic and alveolar hydatid disease of humans caused by infection with Echinococcus granulosus or Echinococcus multilocularis are significant zoonoses in developing countries. For human infections, the main definitive host is the dog, and reduction in the population of unwanted dogs, together with anthelmintic treatment of wanted dogs, are recommended control procedures for these zoonoses. Both owned and unowned dogs have been shown to be a major source of Echinococcus spp. infection in developing countries. Unowned dogs are the most challenging category in dog population management for the control of major zoonotic diseases. Unowned dogs are those dogs that do not have an owner, and those dogs whose owner cannot readily be identified. Control of numbers of unowned dogs can be done in various ways if funds are available. Fertility control and humane euthanasia are likely to be the most effective procedures in developing countries. Fertility control requires significant funding, and where resources are scarce humane euthanasia may be the most effective option. Both procedures are ongoing events, with no predictable end point. This paper examines the sociology and technology for the population management of owned and unowned dogs, specifically for the reduction of human hydatid disease. Examples are given for developing and developed countries. Although a "One Health" approach is desirable, the technology for hydatid control is different from that for rabies, and FAO Animal Welfare recommendations for dog population management should be adjusted accordingly. Copyright © 2014 Elsevier B.V. All rights reserved.
Creswell, Jacob; Sahu, Suvanand; Blok, Lucie; Bakker, Mirjam I; Stevens, Robert; Ditiu, Lucica
2014-01-01
Globally, TB notifications have stagnated since 2007, and sputum smear positive notifications have been declining despite policies to improve case detection. We evaluate results of 28 interventions focused on improving TB case detection. We measured additional sputum smear positive cases treated, defined as the intervention area's increase in case notification during the project compared to the previous year. Projects were encouraged to select control areas and collect historical notification data. We used time series negative binomial regression for over-dispersed cross-sectional data accounting for fixed and random effects to test the individual projects' effects on TB notification while controlling for trend and control populations. Twenty-eight projects, 19 with control populations, completed at least four quarters of case finding activities, covering a population of 89.2 million. Among all projects sputum smear positive (SS+) TB notifications increased 24.9% and annualized notification rates increased from 69.1 to 86.2/100,000 (p = 0.0209) during interventions. Among the 19 projects with control populations, SS+TB case notifications increased 36.9% increase while in the control populations a 3.6% decrease was observed. Fourteen (74%) of the 19 projects' SS+TB notification rates in intervention areas increased from the baseline to intervention period when controlling for historical trends and notifications in control areas. Interventions were associated with large increases in TB notifications across many settings, using an array of interventions. Many people with TB are not reached using current approaches. Different methods and interventions tailored to local realities are urgently needed.
Population dynamics of pond zooplankton, I. Diaptomus pallidus Herrick
Armitage, K.B.; Saxena, B.; Angino, E.E.
1973-01-01
The simultaneous and lag relationships between 27 environmental variables and seven population components of a perennial calanoid copepod were examined by simple and partial correlations and stepwise regression. The analyses consistently explained more than 70% of the variation of a population component. The multiple correlation coefficient (R) usually was highest in no lag or in 3-week or 4-week lag except for clutch size in which R was highest in 1-week lag. Population control, egg-bearing, and clutch size were affected primarily by environmental components categorized as weather; food apparently was relatively minor in affecting population control or reproduction. ?? 1973 Dr. W. Junk B.V. Publishers.
Modeling the relationship between wolf control and cattle depredation
2017-01-01
Wolf control to reduce cattle depredation is an important issue to ecology and agriculture in the United States. Two recent papers use the same dataset having wolf population characteristics and cattle depredation, but come to opposing conclusions concerning the link between wolf control and cattle depredation. Our paper aims to resolve this issue by using the same dataset and developing a model based on a causal association that would explain the nature of the relationship between wolf control and cattle depredation. We use the data on wolf population, number of cattle, number of wolves killed and number of cattle killed, from the U.S. Fish and Wildlife Services Interagency Annual Wolf Reports over the period of 1987–2012. We find a positive link between wolf control and cattle depredation. However, it would be incorrect to infer that wolf control has a positive effect on the number of cattle depredated. We maintain that this link comes from a growing wolf population, which increases cattle depredation, and in turn, causes an increase in the number of wolves killed. While the wolf population is growing, we see both wolf removal and cattle depredation simultaneously grow. It is not until the wolf population growth nears the steady state, that removal of wolves has a sufficient negative effect to reduce or stabilize the number of cattle depredated. PMID:29084261
Veronesi, Rodolfo; Carrieri, Marco; Maccagnani, Bettina; Maini, Stefano; Bellini, Romeo
2015-03-01
The aim of our study was to assess the potential of Macrocyclops albidus as a biological control agent against the 1st and 2nd instars of Culex pipiens and Aedes albopictus. Under laboratory conditions of prey saturation (50 1st instars/copepod), an average of 58.98% of Cx. pipiens and 54.99% of Ae. albopictus larvae were killed by 1 copepod in 24 h. Trials run in big drums containing 200 liters of water showed that the M. albidus population, inoculated in April, efficiently controlled the mosquito population for the entire season. The predator was particularly effective against Ae. albopictus, as only 2 larvae of this species were found in the treated drums, compared to 814 larvae in untreated control drums throughout the study period. No difference was observed in the control efficacy between the 2 initial densities of copepods used. The reduction in Ae. albopictus density in the drums with 100 and 500 M. albidus with respect to the control drums was 99.90 ± 0.35% and 100.0 ± 0.0%, respectively. For Cx. pipiens, the reduction in density was 88.69 ± 13.51% and 84.65% in drums inoculated with 100 and 500 copepods, respectively. Macrocyclops albidus populations survived through the winter and continued to keep the mosquito population under control during the 2008 season. The M. albidus population developed very well both in drums placed in sunny and shaded areas and proved to be tolerant to both high (summer) and low (winter) temperatures. Trials performed on M. albidus survival in catch basins showed that after a few weeks, the copepod population dramatically decreased and subsequently disappeared. The main problem for copepod survival in catch basins seemed to be the low oxygen tension and accumulation of toxic substances, rather than copepods being flushed out in heavy rainfall episodes. During the period when copepods were present, they maintained the mosquito population under control; their partial disappearance from the catch basins, however, would require more recolonization intervention to maintain mosquito control during the season.
D'Cunha, Anitha; Pandit, Lekha; Malli, Chaithra
2017-06-01
Indian data have been largely missing from genome-wide databases that provide information on genetic variations in different populations. This hinders association studies for complex disorders in India. This study was aimed to determine whether the complex genetic structure and endogamy among Indians could potentially influence the design of case-control studies for autoimmune disorders in the south Indian population. A total of 12 single nucleotide variations (SNVs) related to genes associated with autoimmune disorders were genotyped in 370 healthy individuals belonging to six different caste groups in southern India. Allele frequencies were estimated; genetic divergence and phylogenetic relationship within the various caste groups and other HapMap populations were ascertained. Allele frequencies for all genotyped SNVs did not vary significantly among the different groups studied. Wright's FSTwas 0.001 per cent among study population and 0.38 per cent when compared with Gujarati in Houston (GIH) population on HapMap data. The analysis of molecular variance results showed a 97 per cent variation attributable to differences within the study population and <1 per cent variation due to differences between castes. Phylogenetic analysis showed a separation of Dravidian population from other HapMap populations and particularly from GIH population. Despite the complex genetic origins of the Indian population, our study indicated a low level of genetic differentiation among Dravidian language-speaking people of south India. Case-control studies of association among Dravidians of south India may not require stratification based on language and caste.
Population and prehistory II: Space-limited human populations in constant environments
Puleston, Cedric O.; Tuljapurkar, Shripad
2010-01-01
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 nontrivial 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. PMID:18598711
Temporal genetic stability of Stegomyia aegypti (= Aedes aegypti) populations.
Gloria-Soria, A; Kellner, D A; Brown, J E; Gonzalez-Acosta, C; Kamgang, B; Lutwama, J; Powell, J R
2016-06-01
The mosquito Stegomyia aegypti (= Aedes aegypti) (Diptera: Culicidae) is the primary vector of viruses that cause yellow fever, dengue and Chikungunya fever. In the absence of effective vaccines, the reduction of these diseases relies on vector control strategies. The success of these strategies is tightly linked to the population dynamics of target populations. In the present study, 14 collections from St. aegypti populations separated by periods of 1-13 years were analysed to determine their temporal genetic stability. Although temporal structure is discernible in most populations, the degree of temporal differentiation is dependent on the population and does not obscure the geographic structure of the various populations. The results suggest that performing detailed studies in the years prior to and after population reduction- or modification-based control interventions at each target field site may be useful in assessing the probability of success. © 2016 The Royal Entomological Society.
Population and prehistory II: space-limited human populations in constant environments.
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.
Modelling the dynamics of feral alfalfa populations and its management implications.
Bagavathiannan, Muthukumar V; Begg, Graham S; Gulden, Robert H; Van Acker, Rene C
2012-01-01
Feral populations of cultivated crops can pose challenges to novel trait confinement within agricultural landscapes. Simulation models can be helpful in investigating the underlying dynamics of feral populations and determining suitable management options. We developed a stage-structured matrix population model for roadside feral alfalfa populations occurring in southern Manitoba, Canada. The model accounted for the existence of density-dependence and recruitment subsidy in feral populations. We used the model to investigate the long-term dynamics of feral alfalfa populations, and to evaluate the effectiveness of simulated management strategies such as herbicide application and mowing in controlling feral alfalfa. Results suggest that alfalfa populations occurring in roadside habitats can be persistent and less likely to go extinct under current roadverge management scenarios. Management attempts focused on controlling adult plants alone can be counterproductive due to the presence of density-dependent effects. Targeted herbicide application, which can achieve complete control of seedlings, rosettes and established plants, will be an effective strategy, but the seedbank population may contribute to new recruits. In regions where roadside mowing is regularly practiced, devising a timely mowing strategy (early- to mid-August for southern Manitoba), one that can totally prevent seed production, will be a feasible option for managing feral alfalfa populations. Feral alfalfa populations can be persistent in roadside habitats. Timely mowing or regular targeted herbicide application will be effective in managing feral alfalfa populations and limit feral-population-mediated gene flow in alfalfa. However, in the context of novel trait confinement, the extent to which feral alfalfa populations need to be managed will be dictated by the tolerance levels established by specific production systems for specific traits. The modelling framework outlined in this paper could be applied to other perennial herbaceous plants with similar life-history characteristics.
Fragoso, Yara Dadalti; Gomes, Sidney; Goncalves, Marcus Vinicius M; Machado, Suzana C Nunes; Morales, Rogerio de Rizo; Oliveira, Francisco Tomas M de; Oliveira, João Filipe de; Olmo, Neide R Simoes; Parolin, Monica K Fiuza; Siquineli, Fabio; Stoney, Patrick N
2015-10-01
Purpose Recent papers suggest that patients with multiple sclerosis (MS) are prone to alcohol misuse. This may be due to the combination of a lifelong and disabling disease with a psychiatric profile typical of MS. The objective of the present study was to assess these findings in a culturally different population of patients with MS.Method The present case-control transversal study assessed 168 patients with MS and 168 control subjects from Brazil.Results There were no evidence that patients with MS drank more alcohol or, smoked more than did controls. In fact, control subjects had a significantly higher alcohol consumption. The only trait associated to higher alcohol consumption was anxiety, both for patients and controls.Conclusion Unlike previous reports in the literature, patients with MS in our study did not drink or smoked more than a control population.
Knudson, Angélica; Ariza, Yoseth; López, Myriam C; Fajardo, Oscar S; Reyes, Patricia; Moncada, Ligia I; Duque, Sofía; Álvarez, Carlos A; Nicholls, Rubén S
2012-08-01
Evaluating the effect of ivermectin on soil-transmitted helminthes (STH) infection frequency in a Colombian population included in the Onchocerciasis Elimination Program for the Americas (OEPA). This was an impact evaluation study which adopted a longitudinal approach using the population of Naicioná (1996) as baseline for comparison to people from the same population as controls (2008). The cross-sectional approach involved comparing the reference population of Naicioná (2008) to the population of Dos Quebradas (2008) used as controls. Fecal samples were processed by a modified Ritchie-Frick method. Ascaris lumbricoides was the most frequently found parasite in Naicioná (60/121; 49.6 %: 37.8-63.895%CI) and in Dos Quebradas (36/76; 47.4 %: 33.2-65.6 95 % CI). Ivermectin's main effect on the population aged over 5 years was a decreased risk of Trichiuris trichiura infection in both longitudinal assessment (86 % reduction: 74-93 95 % CI) and cross-sectional assessment (63 %:24-82 95 % CI). A 93 % reduction (45-99 95 % CI) in Strongyloides stercoralis frequency was found in longitudinal assessment, compared to 85 % in cross-sectional assessment (-031-99 95 % CI). Ivermectin use in the OEPA is not sufficient for STH morbidity control. Integrated programs including education and basic sanitation are required.
Campbell, Norm; Ordunez, Pedro; Jafe, Marc G.; Orias, Marcelo; DiPete, Donald J.; Patel, Pragna; Khan, Nadia; Onuma, Oyere; Lackland, Daniel T.
2017-01-01
The ability to reliably evaluate the impact of interventions and changes in hypertension prevalence and control is critical if the burden of hypertension-related disease is to be reduced. Previously, a World Hypertension League Expert Committee made recommendations to standardize the reporting of population blood pressure surveys. We have added to those recommendations and also provide modified recommendations from a Pan American Health Organization expert meeting for “performance indicators” to be used to evaluate clinical practices. Core indicators for population surveys are recommended to include: (1) mean systolic blood pressure and (2) mean diastolic blood pressure, and the prevalences of: (3) hypertension, (4) awareness of hypertension, (5) drug-treated hypertension, and (6) drug-treated and controlled hypertension. Core indicators for clinical registries are recommended to include: (1) the prevalence of diagnosed hypertension and (2) the ratio of diagnosed hypertension to that expected by population surveys, and the prevalences of: (3) controlled hypertension, (4) lack of blood pressure measurement within a year in people diagnosed with hypertension, and (5) missed visits by people with hypertension. Definitions and additional indicators are provided. Widespread adoption of standardized population and clinical hypertension performance indicators could represent a major step forward in the effort to control hypertension. PMID:28191704
[Population changes and social welfare tasks].
Lee, H K
1985-07-01
Efforts to control population growth made during the last 20 years are expected to maintain a stable population in the future. We cannot limit our concern to the control of population growth but must consider the social welfare task in the aspect of population stability. It is not because population changes set limits to artificial control, but because the order of population changes presents a desirable sign for low fertility. Another important concern is to pay attention to how to make human beings already born and those to be born in the future enjoy their quality of life. Socioeconomic stability requires economic stabilization to meet basic essential needs. Changes in population structure, along with the quantitative growth of population, make changes in patterns of social welfare demands. When the pyramid type of population structure becomes changed to the bell or pot type of population structure, changes in education and employment as well as changes in problems of the aged and medical demands must be made. On the other hand, population changes accompany value changes in the process of modernization of society. These multiple social changes bring about a value of individualism and a nuclear family norm, and an enlargement of women's social participation which, in turn, can cause family problems. At the same time, social deviations and failures may be increased in the industrial society, and, thus, welfare countermeasures have to be taken. In this respect, the base of social welfare for meeting basic demands must be formed not in the past, narrow sense but in the long range and multisided aspects.
Coupled Flip-Flop Model for REM Sleep Regulation in the Rat
Dunmyre, Justin R.; Mashour, George A.; Booth, Victoria
2014-01-01
Recent experimental studies investigating the neuronal regulation of rapid eye movement (REM) sleep have identified mutually inhibitory synaptic projections among REM sleep-promoting (REM-on) and REM sleep-inhibiting (REM-off) neuronal populations that act to maintain the REM sleep state and control its onset and offset. The control mechanism of mutually inhibitory synaptic interactions mirrors the proposed flip-flop switch for sleep-wake regulation consisting of mutually inhibitory synaptic projections between wake- and sleep-promoting neuronal populations. While a number of synaptic projections have been identified between these REM-on/REM-off populations and wake/sleep-promoting populations, the specific interactions that govern behavioral state transitions have not been completely determined. Using a minimal mathematical model, we investigated behavioral state transition dynamics dictated by a system of coupled flip-flops, one to control transitions between wake and sleep states, and another to control transitions into and out of REM sleep. The model describes the neurotransmitter-mediated inhibitory interactions between a wake- and sleep-promoting population, and between a REM-on and REM-off population. We proposed interactions between the wake/sleep and REM-on/REM-off flip-flops to replicate the behavioral state statistics and probabilities of behavioral state transitions measured from experimental recordings of rat sleep under ad libitum conditions and after 24 h of REM sleep deprivation. Reliable transitions from REM sleep to wake, as dictated by the data, indicated the necessity of an excitatory projection from the REM-on population to the wake-promoting population. To replicate the increase in REM-wake-REM transitions observed after 24 h REM sleep deprivation required that this excitatory projection promote transient activation of the wake-promoting population. Obtaining the reliable wake-nonREM sleep transitions observed in the data required that activity of the wake-promoting population modulated the interaction between the REM-on and REM-off populations. This analysis suggests neuronal processes to be targeted in further experimental studies of the regulatory mechanisms of REM sleep. PMID:24722577
Coupled flip-flop model for REM sleep regulation in the rat.
Dunmyre, Justin R; Mashour, George A; Booth, Victoria
2014-01-01
Recent experimental studies investigating the neuronal regulation of rapid eye movement (REM) sleep have identified mutually inhibitory synaptic projections among REM sleep-promoting (REM-on) and REM sleep-inhibiting (REM-off) neuronal populations that act to maintain the REM sleep state and control its onset and offset. The control mechanism of mutually inhibitory synaptic interactions mirrors the proposed flip-flop switch for sleep-wake regulation consisting of mutually inhibitory synaptic projections between wake- and sleep-promoting neuronal populations. While a number of synaptic projections have been identified between these REM-on/REM-off populations and wake/sleep-promoting populations, the specific interactions that govern behavioral state transitions have not been completely determined. Using a minimal mathematical model, we investigated behavioral state transition dynamics dictated by a system of coupled flip-flops, one to control transitions between wake and sleep states, and another to control transitions into and out of REM sleep. The model describes the neurotransmitter-mediated inhibitory interactions between a wake- and sleep-promoting population, and between a REM-on and REM-off population. We proposed interactions between the wake/sleep and REM-on/REM-off flip-flops to replicate the behavioral state statistics and probabilities of behavioral state transitions measured from experimental recordings of rat sleep under ad libitum conditions and after 24 h of REM sleep deprivation. Reliable transitions from REM sleep to wake, as dictated by the data, indicated the necessity of an excitatory projection from the REM-on population to the wake-promoting population. To replicate the increase in REM-wake-REM transitions observed after 24 h REM sleep deprivation required that this excitatory projection promote transient activation of the wake-promoting population. Obtaining the reliable wake-nonREM sleep transitions observed in the data required that activity of the wake-promoting population modulated the interaction between the REM-on and REM-off populations. This analysis suggests neuronal processes to be targeted in further experimental studies of the regulatory mechanisms of REM sleep.
The biological control of Pomacea canaliculata population by rice-duck mutualism in paddy fields
Kiang Liang; Jia-en Zhang; Li Fang; Benliang Zaho; Mingzhu Luo; Prem Parajuli; Ying Ouyang
2013-01-01
Duck has been used as a non-chemical control method against Pomacea canaliculata Lamarck, but little is known about its principles that underlie the control of snail populations. An indoor experiment was initially used to observe the predation potential of ducks, followed by replicated field trials. In the indoor studies, ducks effectively preyed on...
NASA Astrophysics Data System (ADS)
De la Sen, Manuel; Garrido, Aitor J.
2016-11-01
This paper investigates sufficient conditions of almost periodic solutions of an epidemiological model under impulsive controls. Such impulsive controls are either vaccination actions or abrupt variations of the infected population due to infected immigration or lost of infective numbers due to either vaccination or lost of infected population by out-migration.
Fancelli, Marilene; Dias, Alex Batista; Delalibera, Italo; de Jesus, Sandra Cerqueira; do Nascimento, Antonio Souza; Silva, Sebastião de Oliveira e; Caldas, Ranulfo Correa; Ledo, Carlos Alberto da Silva
2013-01-01
The objective of this study was to select strains of Beauveria bassiana for controlling Cosmopolites sordidus (Germ.) in plantain farms (cv. Terra) of the "Recôncavo" and southern regions in the state of Bahia, Brazil. The virulence of 32 B. bassiana isolates against C. sordidus was determined under laboratory conditions. Three isolates (CNPMF 407, CNPMF 218, and CNPMF 416) were selected for evaluation under field conditions in plantations located in the counties of Mutuípe and Wenceslau Guimarães. Population of C. sordidus was estimated every 15 days by using pseudostem traps. The efficiency of the three strains of B. bassiana was compared to chemical control (carbofuran, 4 g/trap) and absence of control. Carbofuran caused around 90% of adult mortality after 12 months, with a reduction in the population of C. sordidus since the first evaluation. A low number of trapped insects was observed in the fungus-treated plots, suggesting the efficiency of the isolates in controlling the C. sordidus population. The strain CNPMF 218 was the most efficient in controlling C. sordidus adults in both locations, causing around 20% mortality, leading to 40% population size reduction after 12 months.
Dias, Alex Batista; Delalibera Júnior, Italo; de Jesus, Sandra Cerqueira; do Nascimento, Antonio Souza; Silva, Sebastião de Oliveira e; Caldas, Ranulfo Correa; Ledo, Carlos Alberto da Silva
2013-01-01
The objective of this study was to select strains of Beauveria bassiana for controlling Cosmopolites sordidus (Germ.) in plantain farms (cv. Terra) of the “Recôncavo” and southern regions in the state of Bahia, Brazil. The virulence of 32 B. bassiana isolates against C. sordidus was determined under laboratory conditions. Three isolates (CNPMF 407, CNPMF 218, and CNPMF 416) were selected for evaluation under field conditions in plantations located in the counties of Mutuípe and Wenceslau Guimarães. Population of C. sordidus was estimated every 15 days by using pseudostem traps. The efficiency of the three strains of B. bassiana was compared to chemical control (carbofuran, 4g/trap) and absence of control. Carbofuran caused around 90% of adult mortality after 12 months, with a reduction in the population of C. sordidus since the first evaluation. A low number of trapped insects was observed in the fungus-treated plots, suggesting the efficiency of the isolates in controlling the C. sordidus population. The strain CNPMF 218 was the most efficient in controlling C. sordidus adults in both locations, causing around 20% mortality, leading to 40% population size reduction after 12 months. PMID:24187659
Mangen, M-J J; Nielen, M; Burrell, A M
2002-12-18
We examined the importance of pig-population density in the area of an outbreak of classical swine fever (CSF) for the spread of the infection and the choice of control measures. A spatial, stochastic, dynamic epidemiological simulation model linked to a sector-level market-and-trade model for The Netherlands were used. Outbreaks in sparsely and densely populated areas were compared under four different control strategies and with two alternative trade assumptions. The obligatory control strategy required by current EU legislation was predicted to be enough to eradicate an epidemic starting in an area with sparse pig population. By contrast, additional control measures would be necessary if the outbreak began in an area with high pig density. The economic consequences of using preventive slaughter rather than emergency vaccination as an additional control measure depended strongly on the reactions of trading partners. Reducing the number of animal movements significantly reduced the size and length of epidemics in areas with high pig density. The phenomenon of carrier piglets was included in the model with realistic probabilities of infection by this route, but it made a negligible contribution to the spread of the infection.
Rabies disease dynamics in naïve dog populations in Australia.
Sparkes, Jessica; McLeod, Steven; Ballard, Guy; Fleming, Peter J S; Körtner, Gerhard; Brown, Wendy Y
2016-09-01
Currently, Australia is free from terrestrial rabies but an incursion from nearby Indonesia, where the virus is endemic, is a feasible threat. Here, we aimed to determine whether the response to a simulated rabies incursion would vary between three extant Australian dog populations; free-roaming domestic dogs from a remote indigenous community in northern Australia, and free-roaming domestic and wild dogs in peri-urban areas of north-east New South Wales. We further sought to predict how different management strategies impacted disease dynamics in these populations. We used simple stochastic state-transition models and dog demographic and contact rate data from the three dog populations to simulate rabies spread, and used global and local sensitivity analyses to determine effects of model parameters. To identify the most effective control options, dog removal and vaccination strategies were also simulated. Responses to simulated rabies incursions varied between the dog populations. Free-roaming domestic dogs from north-east New South Wales exhibited the lowest risk for rabies maintenance and spread. Due to low containment and high contact rates, rabies progressed rapidly through free-roaming dogs from the remote indigenous community in northern Australia. In contrast, rabies remained at relatively low levels within the north-east New South Wales wild dog population for over a year prior to an epidemic. Across all scenarios, sensitivity analyses revealed that contact rates and the probability of transmission were the most important drivers of the number of infectious individuals within a population. The number of infectious individuals was less sensitive to birth and death rates. Removal of dogs as a control strategy was not effective for any population modelled, while vaccination rates in excess of 70% of the population resulted in significant reductions in disease progression. The variability in response between these distinct dog groups to a rabies incursion, suggests that a blanket approach to management would not be effective or feasible to control rabies in Australia. Control strategies that take into account the different population and behavioural characteristics of these dog groups will maximise the likelihood of effective and efficient rabies control in Australia. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.
Pollen limitation in a narrow endemic plant: geographical variation and driving factors.
Fernández, Juande D; Bosch, Jordi; Nieto-Ariza, Beatriz; Gómez, José M
2012-10-01
Pollen limitation may have important consequences for the reproduction and abundance of plant species. It may be especially harmful to endangered and endemic plants with small populations. In this study, we quantify the effect of pollen limitation on seed production and seedling emergence in an endangered narrow endemic crucifer, Erysimum popovii. We conducted a pollen addition experiment across the entire geographic distribution of the species, and explored the effect of pollinator assemblage, plant population size and density, and other habitat variables on pollen limitation intensity in 13 populations. We supplemented flowers in 20 plants per population with allogamous pollen. To account for potential resource reallocation, we used two types of control untreated flowers: internal control flowers from the same individual as the supplemented flowers, and external control flowers from other individuals. Our results indicate that E. popovii is pollen-limited in most of the populations studied, but only through seed production, since pollen supplementation did not enhance seedling emergence. Beefly abundance was associated with among-population differences in pollen limitation intensity. Populations in which beeflies were more abundant were less pollen-limited. In contrast, the abundance of other flower visitors, such as large bees or butterflies, was not associated with pollen limitation. Annual rainfall and bare soil cover were associated with the intensity of pollen limitation across populations.
Seasonal dynamics of snail populations in coastal Kenya: Model calibration and snail control
NASA Astrophysics Data System (ADS)
Gurarie, D.; King, C. H.; Yoon, N.; Wang, X.; Alsallaq, R.
2017-10-01
A proper snail population model is important for accurately predicting Schistosoma transmission. Field data shows that the overall snail population and that of shedding snails have a strong pattern of seasonal variation. Because human hosts are infected by the cercariae released from shedding snails, the abundance of the snail population sets ultimate limits on human infection. For developing a predictive dynamic model of schistosome infection and control strategies we need realistic snail population dynamics. Here we propose two such models based on underlying environmental factors and snail population biology. The models consist of two-stage (young-adult) populations with resource-dependent reproduction, survival, maturation. The key input in the system is seasonal rainfall which creates snail habitats and resources (small vegetation). The models were tested, calibrated and validated using dataset collected in Msambweni (coastal Kenya). Seasonal rainfall in Msambweni is highly variable with intermittent wet - dry seasons. Typical snail patterns follow precipitation peaks with 2-4-month time-lag. Our models are able to reproduce such seasonal variability over extended period of time (3-year study). We applied them to explore the optimal seasonal timing for implementing snail control.
Awasthi, Kiran Raj; Adefemi, Kazeem; Awasthi, Mamata Sherpa; Chalise, Binaya
2018-01-01
Infectious diseases are a major problem for developing countries. Controlling and eradicating these diseases have remained a challenge because of the multitudes of social and environmental factors involved. However, a multi-sectoral and collective effort in dealing with these diseases has been shown to result in positive outcomes. This paper looks at the current situation of Malaria in Nepal and a population that is at high risk. It explains the impact that social and environmental determinants have on this target population. This review then critically examines the various possible public health interventions that could potentially help in the control of malaria in this high risk population, drawing from evidences and experiences reported from other countries with suggestions for adapting these interventions to the Nepali environment.
Productivity losses in chronic obstructive pulmonary disease: a population-based survey.
Erdal, Marta; Johannessen, Ane; Askildsen, Jan Erik; Eagan, Tomas; Gulsvik, Amund; Grønseth, Rune
2014-01-01
We aimed to estimate incremental productivity losses (sick leave and disability) of spirometry-defined chronic obstructive pulmonary disease (COPD) in a population-based sample and in hospital-recruited patients with COPD. Furthermore, we examined predictors of productivity losses by multivariate analyses. We performed four quarterly telephone interviews of 53 and 107 population-based patients with COPD and controls, as well as 102 hospital-recruited patients with COPD below retirement age. Information was gathered regarding annual productivity loss, exacerbations of respiratory symptoms and comorbidities. Incremental productivity losses were estimated by multivariate quantile median regression according to the human capital approach, adjusting for sex, age, smoking habits, education and lung function. Main effect variables were COPD/control status, number of comorbidities and exacerbations of respiratory symptoms. Altogether 55%, 87% and 31% of population-based COPD cases, controls and hospital patients, respectively, had a paid job at baseline. The annual incremental productivity losses were 5.8 (95% CI 1.4 to 10.1) and 330.6 (95% CI 327.8 to 333.3) days, comparing population-recruited and hospital-recruited patients with COPD to controls, respectively. There were significantly higher productivity losses associated with female sex and less education. Additional adjustments for comorbidities, exacerbations and FEV1% predicted explained all productivity losses in the population-based sample, as well as nearly 40% of the productivity losses in hospital-recruited patients. Annual incremental productivity losses were more than 50 times higher in hospital-recruited patients with COPD than that of population-recruited patients with COPD. To ensure a precise estimation of societal burden, studies on patients with COPD should be population-based.
Parobek, Christian M.; Lin, Jessica T.; Saunders, David L.; Barnett, Eric J.; Lon, Chanthap; Lanteri, Charlotte A.; Balasubramanian, Sujata; Brazeau, Nicholas; DeConti, Derrick K.; Garba, Deen L.; Meshnick, Steven R.; Spring, Michele D.; Chuor, Char Meng; Bailey, Jeffrey A.; Juliano, Jonathan J.
2016-01-01
Cambodia, in which both Plasmodium vivax and Plasmodium falciparum are endemic, has been the focus of numerous malaria-control interventions, resulting in a marked decline in overall malaria incidence. Despite this decline, the number of P. vivax cases has actually increased. To understand better the factors underlying this resilience, we compared the genetic responses of the two species to recent selective pressures. We sequenced and studied the genomes of 70 P. vivax and 80 P. falciparum isolates collected between 2009 and 2013. We found that although P. falciparum has undergone population fracturing, the coendemic P. vivax population has grown undisrupted, resulting in a larger effective population size, no discernable population structure, and frequent multiclonal infections. Signatures of selection suggest recent, species-specific evolutionary differences. Particularly, in contrast to P. falciparum, P. vivax transcription factors, chromatin modifiers, and histone deacetylases have undergone strong directional selection, including a particularly strong selective sweep at an AP2 transcription factor. Together, our findings point to different population-level adaptive mechanisms used by P. vivax and P. falciparum parasites. Although population substructuring in P. falciparum has resulted in clonal outgrowths of resistant parasites, P. vivax may use a nuanced transcriptional regulatory approach to population maintenance, enabling it to preserve a larger, more diverse population better suited to facing selective threats. We conclude that transcriptional control may underlie P. vivax’s resilience to malaria control measures. Novel strategies to target such processes are likely required to eradicate P. vivax and achieve malaria elimination. PMID:27911780
Belinato, Thiago Affonso; Valle, Denise
2015-01-01
Several Aedes aegypti field populations are resistant to neurotoxic insecticides, mainly organophoshates and pyrethroids, which are extensively used as larvicides and adulticides, respectively. Diflubenzuron (DFB), a chitin synthesis inhibitor (CSI), was recently approved for use in drinking water, and is presently employed in Brazil for Ae. aegypti control, against populations resistant to the organophosphate temephos. However, tests of DFB efficacy against field Ae. aegypti populations are lacking. In addition, information regarding the dynamics of CSI resistance, and characterization of any potential fitness effects that may arise in conjunction with resistance are essential for new Ae. aegypti control strategies. Here, the efficacy of DFB was evaluated for two Brazilian Ae. aegypti populations known to be resistant to both temephos and the pyrethroid deltamethrin. Laboratory selection for DFB resistance was then performed over six or seven generations, using a fixed dose of insecticide that inhibited 80% of adult emergence in the first generation. The selection process was stopped when adult emergence in the diflubenzuron-treated groups was equivalent to that of the control groups, kept without insecticide. Diflubenzuron was effective against the two Ae. aegypti field populations evaluated, regardless of their resistance level to neurotoxic insecticides. However, only a few generations of DFB selection were sufficient to change the susceptible status of both populations to this compound. Several aspects of mosquito biology were affected in both selected populations, indicating that diflubenzuron resistance acquisition is associated with a fitness cost. We believe that these results can significantly contribute to the design of control strategies involving the use of insect growth regulators.
Using population models to evaluate management alternatives for Gulf Striped Bass
Aspinwall, Alexander P.; Irwin, Elise R.; Lloyd, M. Clint
2017-01-01
Interstate management of Gulf Striped Bass Morone saxatilis has involved a thirty-year cooperative effort involving Federal and State agencies in Georgia, Florida and Alabama (Apalachicola-Chattahoochee-Flint Gulf Striped Bass Technical Committee). The Committee has recently focused on developing an adaptive framework for conserving and restoring Gulf Striped Bass in the Apalachicola, Chattahoochee, and Flint River (ACF) system. To evaluate the consequences and tradeoffs among management activities, population models were used to inform management decisions. Stochastic matrix models were constructed with varying recruitment and stocking rates to simulate effects of management alternatives on Gulf Striped Bass population objectives. An age-classified matrix model that incorporated stock fecundity estimates and survival estimates was used to project population growth rate. In addition, combinations of management alternatives (stocking rates, Hydrilla control, harvest regulations) were evaluated with respect to how they influenced Gulf Striped Bass population growth. Annual survival and mortality rates were estimated from catch-curve analysis, while fecundity was estimated and predicted using a linear least squares regression analysis of fish length versus egg number from hatchery brood fish data. Stocking rates and stocked-fish survival rates were estimated from census data. Results indicated that management alternatives could be an effective approach to increasing the Gulf Striped Bass population. Population abundance was greatest under maximum stocking effort, maximum Hydrilla control and a moratorium. Conversely, population abundance was lowest under no stocking, no Hydrilla control and the current harvest regulation. Stocking rates proved to be an effective management strategy; however, low survival estimates of stocked fish (1%) limited the potential for population growth. Hydrilla control increased the survival rate of stocked fish and provided higher estimates of population abundances than maximizing the stocking rate. A change in the current harvest regulation (50% harvest regulation) was not an effective alternative to increasing the Gulf Striped Bass population size. Applying a moratorium to the Gulf Striped Bass fishery increased survival rates from 50% to 74% and resulted in the largest population growth of the individual management alternatives. These results could be used by the Committee to inform management decisions for other populations of Striped Bass in the Gulf Region.
[Publicizing the fundamental state policy and strengthening population research].
Zheng, G
1983-11-29
In June 1983, a conference on population research was held at Fudan University. A total of more than 40 papers were presented to the conference, and participating scholars vigorously discussed the theme of "controlling population quantity and improving population quality," a policy guideline recommended by Primer Zhao Ziyang. All participants at the conference agreed that China's population growth has reached a climax and that population growth, especially the growth in rural areas, should be put under immediate control. Ideological education is needed to develop family work. In addition, appropriate economic measures in national finance, taxation, material incentives, and business and trade should be taken and linked with national family planning policy. In the area of population quality, more action should be taken to improve birth quality and infant care. Early education for young children should also be emphasized to develop their virtue, wisdom, and physical health in a comprehensive way. Studies of population science should be encouraged, and studies of methodology in population science should be strengthened.
Population pressure. The road from Rio is paved with factions.
Holloway, M
1992-09-01
Groups focused on women's rights, family planning and health, environmental protection, reduced consumption of natural resources, economic development and population control differ greatly in their views of population pressure's role in preventing sustainable development. Yet, it is these same groups that should be working together to achieve sustainable development. Some speakers at the 1991 UN Conference on Environment and Development in Rio de Janeiro, Brazil, encouraged world leaders to take immediate steps to deal with population growth and stated that poverty, environment, and population are intertwined. At the same time in the same city, panel participants at the Global Forum, attended by almost 2000 nongovernmental organizations, considered population control as a violation of women's rights, as a means to circumvent poverty eradication in developing countries, and as a means to suppress the poor in developing countries. These debates, whether population control or economic development is the best means to reduce population growth have been occurring since 1968. In the interim, the world population has increased form 3.5-5.5 billion. The population growth rate has fallen from 2-1.7%, however, but 97 million more people will appear on this earth each year during the 1990s. Because any discussion of contraceptives and family planning may be misinterpreted by members as abortion, many environmental groups do not address it. They also fear undertaking immigration issues, since past attempts were labelled as racist. Nevertheless, more and more organizations, e.g., the Natural Resources Defense Council, are beginning to address the need to focus on population growth to prevent environmental degradation. Further, some foundations, e.g., the Pew Charitable Trusts, are offering grants to environmental groups to begin population programs. All too often development plans neglect family health and do not consider the concerns of the target population.
When can efforts to control nuisance and invasive species backfire?
Zipkin, E.F.; Kraft, C.E.; Cooch, E.G.; Sullivan, P.J.
2009-01-01
Population control through harvest has the potential to reduce the abundance of nuisance and invasive species. However, demographic structure and density-dependent processes can confound removal efforts and lead to undesirable consequences, such as overcompensation (an increase in abundance in response to harvest) and instability (population cycling or chaos). Recent empirical studies have demonstrated the potential for increased mortality (such as that caused by harvest) to lead to overcompensation and instability in plant, insect, and fish populations. We developed a general population model with juvenile and adult stages to help determine the conditions under which control harvest efforts can produce unintended outcomes. Analytical and simulation analyses of the model demonstrated that the potential for overcompensation as a result of harvest was significant for species with high fecundity, even when annual stage-specific survivorship values were fairly low. Population instability as a result of harvest occurred less frequently and was only possible with harvest strategies that targeted adults when both fecundity and adult survivorship were high. We considered these results in conjunction with current literature on nuisance and invasive species to propose general guidelines for assessing the risks associated with control harvest based on life history characteristics of target populations. Our results suggest that species with high per capita fecundity (over discrete breeding periods), short juvenile stages, and fairly constant survivorship rates are most likely to respond undesirably to harvest. It is difficult to determine the extent to which overcompensation and instability could occur during real-world removal efforts, and more empirical removal studies should be undertaken to evaluate population-level responses to control harvests. Nevertheless, our results identify key issues that have been seldom acknowledged and are potentially generic across taxa. ?? 2009 by the Ecological Society ot America.
When can efforts to control nuisance and invasive species backfire?
Zipkin, Elise F; Kraft, Clifford E; Cooch, Evan G; Sullivan, Patrick J
2009-09-01
Population control through harvest has the potential to reduce the abundance of nuisance and invasive species. However, demographic structure and density-dependent processes can confound removal efforts and lead to undesirable consequences, such as overcompensation (an increase in abundance in response to harvest) and instability (population cycling or chaos). Recent empirical studies have demonstrated the potential for increased mortality (such as that caused by harvest) to lead to overcompensation and instability in plant, insect, and fish populations. We developed a general population model with juvenile and adult stages to help determine the conditions under which control harvest efforts can produce unintended outcomes. Analytical and simulation analyses of the model demonstrated that the potential for overcompensation as a result of harvest was significant for species with high fecundity, even when annual stage-specific survivorship values were fairly low. Population instability as a result of harvest occurred less frequently and was only possible with harvest strategies that targeted adults when both fecundity and adult survivorship were high. We considered these results in conjunction with current literature on nuisance and invasive species to propose general guidelines for assessing the risks associated with control harvest based on life history characteristics of target populations. Our results suggest that species with high per capita fecundity (over discrete breeding periods), short juvenile stages, and fairly constant survivorship rates are most likely to respond undesirably to harvest. It is difficult to determine the extent to which overcompensation and instability could occur during real-world removal efforts, and more empirical removal studies should be undertaken to evaluate population-level responses to control harvests. Nevertheless, our results identify key issues that have been seldom acknowledged and are potentially generic across taxa.
Wang, Jin-Jun; Zhang, Jian-Ping; He, Lin; Zhao, Zhi-Mo
2006-01-01
Development, reproduction and acaricide susceptibility of Tetranychus cinnabarinus (Boisduvals) (Acari: Tetranychidae) were investigated after long-term (about 40 generations) exposure to various levels of acid rain; pH 2.5, 3.0, 4.0, and 5.6. Deionized water (pH 6.8) served as a control. The mites were reared on eggplant leaves at 28°C, 80%RH and a photoperiod of 14:10 (L:D) in the laboratory. The results showed that the duration of the immature stage was significantly affected by acid rain exposure. The shortest duration (8.90 days) was recorded for populations exposed to pH 5.6 acid rain, while the longest duration (9.37 days) occurred after exposure to pH 2.5 acid rain. Compared with the control population, adult longevity was shortened with an increase in acidity. Similarly, the oviposition duration was also shortened by an increase in acidity. Statistically, female fecundity did not differ significantly between pH 5.6, pH 4.0 and control populations, but did differ significantly between the control population and those exposed to pH 2.5 and pH 3.0 acid rain. This suggested that the mite suffered reproductive defects after long-term exposure to acid rain with higher acidity (pH 2.5 and 3.0). The intrinsic rate of increase among different populations was not significantly affected, but the net reproductive rate of populations exposed to pH 2.5 and 3.0 acid rain was significantly less than pH4.0, 5.6, and control populations. Bioassay results showed that after long-term exposure to acid rain, susceptibility of the mites to two acaricides, dichlorvos and fenpropathrin, did not change significantly. PMID:19537978
Fontoura, Nathalia Giglio; Bellinato, Diogo Fernandes; Valle, Denise; Lima, José Bento Pereira
2012-05-01
The mosquito Aedes aegypti is the main focus of dengue control campaigns. Because of widespread resistance against conventional chemical insecticides, chitin synthesis inhibitors (CSIs) are considered control alternatives. We evaluated the resistance status of four Brazilian Ae. aegypti populations to both the organophosphate temephos and the pyrethroid deltamethrin, which are used in Brazil to control larvae and adults, respectively. All vector populations exhibited high levels of temephos resistance and varying rates of alterations in their susceptibility to pyrethroids. The effect of the CSI novaluron on these populations was also investigated. Novaluron was effective against all populations under laboratory conditions. Field-simulated assays with partial water replacement were conducted to evaluate novaluron persistence. Bioassays were continued until an adult emergence inhibition of at least 70% was attained. We found a residual effect of eight weeks under indoor conditions and novaluron persisted for five-six weeks in assays conducted in an external area. Our data show that novaluron is effective against the Ae. aegypti populations tested, regardless of their resistance to conventional chemical insecticides.
Moffitt, C.M.; Haukenes, A.H.; Williams, C.J.
2005-01-01
Fishery managers and resource conservationists are increasingly interested in understanding the fish health and disease risks of free-ranging fishes and whether propagated fishes or features and practices used at fish culture facilities pose a health risk to free-ranging populations. Disease agents are present in most both captive and all free-ranging fish populations, but the consequences and extent of infections in free-ranging populations are often difficult to measure, control, and understand. Sampling methods, protocols, and assay techniques developed to assess the health of captive populations are not as applicable for assessments of free-ranging fishes. The use of chemicals and therapeutics to control diseases and parasites in propagated fishes likely reduces the risk of introducing specific pathogens into the environment, but control measures may have localized effects on the environment surrounding fish culture facilities. To understand health risks of propagated and free ranging fishes, we must consider fish populations, culture facilities, fish releases, and their interactions within the greater geospatial features of the aquatic environment. ?? 2004 by the American Fisheries Society.
Koppenhöfer, Albrecht M; Kostromytska, Olga S; Wu, Shaohui
2018-05-25
The annual bluegrass weevil, Listronotus maculicollis Kirby (Coleoptera: Curculionidae), is a major pest of golf course turf in eastern North America with widespread insecticide resistance. This study examined the effect of pyrethroid-resistance level on the efficacy of adulticides and larvicides from different insecticide classes commonly used for L. maculicollis management through greenhouse and field studies. The tested populations had previously been determined to be susceptible, moderately resistant, resistant, and highly resistant to the pyrethroid bifenthrin. Targeting adults, efficacy was significantly reduced for bifenthrin against the highly resistant population and for the spinosyn spinosad and the oxadizine indoxacarb against the resistant and highly resistant populations. Efficacy of the organophosphate chlorpyrifos was not significantly reduced. No adulticide provided significant control of resistant and highly resistant populations. Targeting larvae, the efficacy of spinosad and the anthranilic diamide cyantraniliprole was marginally reduced against the highly resistant population. Significant reductions in efficacy and no significant control were observed for indoxacarb against the highly resistant population and for the neonicotinoid clothianidin, the anthranilic diamide chlorantraniliprole, and the organophosphate trichlorfon against the resistant and highly resistant populations. Our findings lay the groundwork for management recommendations for populations with different resistance levels. Generally, synthetic insecticide applications should be minimized with greater use of larvicides supplemented with nonchemical control alternatives. The remaining effective larvicides should be rotated using cyantraniliprole, spinosad, and indoxacarb against resistant and cyantraniliprole and spinosad against highly resistant populations.
Li, Lin; Zhang, Min; Holman, C D'Arcy J
2013-01-01
To investigate the internal validity of a food-frequency questionnaire (FFQ) developed for use in Chinese women and to compare habitual dietary intakes between population and hospital controls measured by the FFQ. A quantitative FFQ and a short food habit questionnaire (SFHQ) were developed and adapted for cancer and nutritional studies. Habitual dietary intakes were assessed in 814 Chinese women aged 18-81 years (407 outpatients and 407 population controls) by face-to-face interview using the FFQ in Shenyang, Northeast China in 2009-2010. The Goldberg formula (ratio of energy intake to basal metabolic rate, EI/BMR) was used to assess the validity of the FFQ. Correlation analyses compared the SFHQ variables with those of the quantitative FFQ. Differences in dietary intakes between hospital and population controls were investigated. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained using conditional logistic regression analyses. The partial correlation coefficients were moderate to high (0.42 to 0.80; all p<0.05) for preserved food intake, fat consumption and tea drinking variables between the SFHQ and the FFQ. The average EI/BMR was 1.93 with 88.5% of subjects exceeding the Goldberg cut-off value of 1.35. Hospital controls were comparable to population controls in consumption of 17 measured food groups and mean daily intakes of energy and selected nutrients. The FFQ had reasonable validity to measure habitual dietary intakes of Chinese women. Hospital outpatients provide a satisfactory control group for food consumption and intakes of energy and nutrients measured by the FFQ in a Chinese hospital setting.
2011-01-01
Background Hypertension may increase tortuosity or twistedness of arteries. We applied a centerline extraction algorithm and tortuosity metric to magnetic resonance angiography (MRA) brain images to quantitatively measure the tortuosity of arterial vessel centerlines. The most commonly used arterial tortuosity measure is the distance factor metric (DFM). This study tested a DFM based measurement’s ability to detect increases in arterial tortuosity of hypertensives using existing images. Existing images presented challenges such as different resolutions which may affect the tortuosity measurement, different depths of the area imaged, and different artifacts of imaging that require filtering. Methods The stability and accuracy of alternative centerline algorithms was validated in numerically generated models and test brain MRA data. Existing images were gathered from previous studies and clinical medical systems by manually reading electronic medical records to identify hypertensives and negatives. Images of different resolutions were interpolated to similar resolutions. Arterial tortuosity in MRA images was measured from a DFM curve and tested on numerically generated models as well as MRA images from two hypertensive and three negative control populations. Comparisons were made between different resolutions, different filters, hypertensives versus negatives, and different negative controls. Results In tests using numerical models of a simple helix, the measured tortuosity increased as expected with more tightly coiled helices. Interpolation reduced resolution-dependent differences in measured tortuosity. The Korean hypertensive population had significantly higher arterial tortuosity than its corresponding negative control population across multiple arteries. In addition one negative control population of different ethnicity had significantly less arterial tortuosity than the other two. Conclusions Tortuosity can be compared between images of different resolutions by interpolating from lower to higher resolutions. Use of a universal negative control was not possible in this study. The method described here detected elevated arterial tortuosity in a hypertensive population compared to the negative control population and can be used to study this relation in other populations. PMID:22166145
Diedrich, Karl T; Roberts, John A; Schmidt, Richard H; Kang, Chang-Ki; Cho, Zang-Hee; Parker, Dennis L
2011-10-18
Hypertension may increase tortuosity or twistedness of arteries. We applied a centerline extraction algorithm and tortuosity metric to magnetic resonance angiography (MRA) brain images to quantitatively measure the tortuosity of arterial vessel centerlines. The most commonly used arterial tortuosity measure is the distance factor metric (DFM). This study tested a DFM based measurement's ability to detect increases in arterial tortuosity of hypertensives using existing images. Existing images presented challenges such as different resolutions which may affect the tortuosity measurement, different depths of the area imaged, and different artifacts of imaging that require filtering. The stability and accuracy of alternative centerline algorithms was validated in numerically generated models and test brain MRA data. Existing images were gathered from previous studies and clinical medical systems by manually reading electronic medical records to identify hypertensives and negatives. Images of different resolutions were interpolated to similar resolutions. Arterial tortuosity in MRA images was measured from a DFM curve and tested on numerically generated models as well as MRA images from two hypertensive and three negative control populations. Comparisons were made between different resolutions, different filters, hypertensives versus negatives, and different negative controls. In tests using numerical models of a simple helix, the measured tortuosity increased as expected with more tightly coiled helices. Interpolation reduced resolution-dependent differences in measured tortuosity. The Korean hypertensive population had significantly higher arterial tortuosity than its corresponding negative control population across multiple arteries. In addition one negative control population of different ethnicity had significantly less arterial tortuosity than the other two. Tortuosity can be compared between images of different resolutions by interpolating from lower to higher resolutions. Use of a universal negative control was not possible in this study. The method described here detected elevated arterial tortuosity in a hypertensive population compared to the negative control population and can be used to study this relation in other populations.
Ryon, Allen D.; Haas, Paul A.; Vavruska, John S.
1984-01-01
The present invention is directed to a method and apparatus for making a population of dense, closely size-controlled microspheres by sol-gel procedures wherein said microspheres are characterized by a significant percentage of said population being within a predetermined, relatively narrow size range. Microsphere populations thus provided are useful in vibratory-packed processes for nuclear fuels to be irradiated in LWR- and FBR-type nuclear reactors.
Kok, Ching Mun; Sieo, Chin Chin; Tan, Hui Yin; Saad, Wan Zuhainis; Liang, Juan Boo; Ho, Yin Wan
2013-10-01
The effect of Leucaena leucocephala hybrid-Bahru (LLB), which contains a high concentration of condensed tannins, on cellulolytic rumen fungal population in goats was investigated using real-time PCR. The fungal population in goats fed LLB was inhibited during the first 10 days of feeding, but after 15 days of feeding, there was a tremendous increase of fungal population (157.0 μg/ml), which was about fourfold more than that in control goats (39.7 μg/ml). However, after this period, the fungal population decreased continuously, and at 30 days of feeding, the fungal population (50.6 μg/ml) was not significantly different from that in control goats (55.4 μg/ml).
Al-Shaqha, Waleed M; Alkharfy, Khalid M; Al-Daghri, Nasser M; Mohammed, Abdul Khader
2015-01-01
There have been inconsistent reports on N-acetyltransferase (NAT) gene polymorphism in type 2 diabetes mellitus (T2DM), and data is particularly limited in the Arab population. Therefore, the main objective of this study was to identify whether the genetic polymorphisms of NAT1 and NAT2 play a role in susceptibility to T2DM in the Saudi population. A population-based, prospective genetic association case-control study on a Saudi population. Whole blood, anthropometric measurements and biochemistry data were collected from 369 Saudi individuals (186 T2DM patients and 183 healthy controls). DNA was isolated from the blood. Polymorphism of NAT1 and NAT2 SNPs [NAT2*7B, rs1041983(C > T); NAT2*7, rs1799931(G > A); NAT2*6A, rs1799930(G > A); NAT2*5A, rs1799929(C > T); and NAT1*11A, rs4986988(C > T)] were evaluated by allelic discrimination using real-time PCR. Subjects with T2DM had a significantly increased body mass index (BMI), waist circumference, sys.tolic and diastolic blood pressure, glucose, triglycerides, and LDL-cholesterol compared with healthy controls (P < .05). The rs1799931(G > A) genotype was detected in the control population but not in the T2DM population (P < .001). The wild type (G) allele frequency was higher in T2DM than controls (P=.038). The mutant allele (A) in rs1799931(G > A) had a protective effect for T2DM (OR 0.32, 95% CI 0.16-0.62; P=.001). Regression analysis showed that BMI, systolic BP and triglycerides are potential risk factors for T2DM. The genotypes as well as the individual alleles of rs1799931(G > A) differed significantly be.tween the case and control populations. The variation in the data reported so far suggest that polymorphism of the NAT gene may vary among different geographical areas. Environmental or dietary factors may also contribute to disease manifestation.
Sun, H; Yang, M; Fung, M; Chan, S; Jawi, M; Anderson, T; Poon, M-C; Jackson, S
2017-09-01
Endothelial function has been identified as an independent predictor of cardiovascular risk in the general population. It is unclear if the haemophilia population has a different endothelial function profile compared to the healthy population. This prospective study aims to assess if there is a difference in endothelial function between haemophilia patients and healthy controls, and the impact of endothelial function on vascular outcomes in the haemophilia population. Baseline cardiovascular risk factors and endothelial function were presented. Adult males with haemophilia A or B recruited from the British Columbia and Southern Alberta haemophilia treatment centres were matched to healthy male controls by age and cardiovascular risk factors. Macrovascular endothelial function was assessed by brachial artery flow-mediated dilation (FMD) and nitroglycerin-mediated dilation (NMD), and microvascular endothelial function was assessed by hyperaemic velocity time integral (VTI). Multivariable linear regression was used to assess the association between haemophilia and endothelial function. A total of 81 patients with haemophilia and 243 controls were included. Patients with haemophilia had a similar FMD and NMD compared to controls, although haemophilia was associated with higher FMD on multivariable analysis. Haemophilia was associated with significantly lower VTI on univariate and multivariable analyses, regardless of haemophilia type and severity. Adult males with haemophilia appear to have lower microvascular endothelial function compared to healthy controls. Future studies to assess the impact of endothelial dysfunction on cardiovascular events in the haemophilia population are needed. © 2017 John Wiley & Sons Ltd.
ERIC Educational Resources Information Center
Kinyanda, Eugene; Hjelmeland, Heidi; Musisi, Seggane
2005-01-01
Psychological factors associated with deliberate self-harm (DSH) as seen in an African population in Uganda are described. A case-control study design was employed in which a Luganda version (predominant language in the study area) of the modified European Parasuicide Interview Schedule I (EPSIS I) was used to collect data. The controls were…
ERIC Educational Resources Information Center
Thelin Bronner, Kerstin Birgitta; Wennberg, Peter; Kallmen, Hakan; Schult, Marie-Louise Birgitta
2012-01-01
This prospective study aimed to describe alcohol habits in patients with chronic pain compared with those in a matched control group from the general Swedish population. In total, 100 consecutive patients enrolled were matched against 100 individuals in a control group on the basis of age and sex. Alcohol habits were measured using the Alcohol Use…
Wolff, Jonci Nikolai; Gemmell, Neil J; Tompkins, Daniel M; Dowling, Damian K
2017-05-03
Pests are a global threat to biodiversity, ecosystem function, and human health. Pest control approaches are thus numerous, but their implementation costly, damaging to non-target species, and ineffective at low population densities. The Trojan Female Technique (TFT) is a prospective self-perpetuating control technique that is species-specific and predicted to be effective at low densities. The goal of the TFT is to harness naturally occurring mutations in the mitochondrial genome that impair male fertility while having no effect on females. Here, we provide proof-of-concept for the TFT, by showing that introduction of a male fertility-impairing mtDNA haplotype into replicated populations of Drosophila melanogaster causes numerical population suppression, with the magnitude of effect positively correlated with its frequency at trial inception. Further development of the TFT could lead to establishing a control strategy that overcomes limitations of conventional approaches, with broad applicability to invertebrate and vertebrate species, to control environmental and economic pests.
Mourtzinis, Georgios; Adamsson Eryd, Samuel; Rosengren, Annika; Björck, Lena; Adiels, Martin; Johannsson, Gudmundur; Manhem, Karin
2018-05-01
Background Atrial fibrillation is associated with hyperthyroidism. Patients with primary aldosteronism have an increased prevalence of atrial fibrillation. However, the prevalence of primary aldosteronism in the atrial fibrillation population is unknown. Aim This nationwide case-control study aimed to compare the prevalence of primary aldosteronism and thyroid disorders in patients with atrial fibrillation with that of age- and sex-matched controls. Methods We identified all atrial fibrillation cases in Sweden between 1987 and 2013 ( n = 713,569) by using the Swedish National Patient Register. A control cohort without atrial fibrillation was randomly selected from the Swedish Total Population Register with a case to control ratio of 1:2. This control cohort was matched for age, sex and place of birth ( n = 1,393,953). Results The prevalence of primary aldosteronism in December 2013 was 0.056% in the atrial fibrillation cohort and 0.024% in controls. At the same time, the prevalence of hypothyroidism was 5.9% in the atrial fibrillation cohort and 3.7% in controls. The prevalence of hyperthyroidism was 2.3% in the atrial fibrillation cohort and 0.8% in controls. Conclusion This study shows, for the first time, a doubled prevalence of primary aldosteronism in a large cohort of patients with atrial fibrillation compared with the general population. There is also an increased prevalence of hypo- and hyper-thyroidism in patients with atrial fibrillation compared with the general population.
Design of vaccination and fumigation on Host-Vector Model by input-output linearization method
NASA Astrophysics Data System (ADS)
Nugraha, Edwin Setiawan; Naiborhu, Janson; Nuraini, Nuning
2017-03-01
Here, we analyze the Host-Vector Model and proposed design of vaccination and fumigation to control infectious population by using feedback control especially input-output liniearization method. Host population is divided into three compartments: susceptible, infectious and recovery. Whereas the vector population is divided into two compartment such as susceptible and infectious. In this system, vaccination and fumigation treat as input factors and infectious population as output result. The objective of design is to stabilize of the output asymptotically tend to zero. We also present the examples to illustrate the design model.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Devarakonda, M.S.
1988-01-01
Control over population dynamics and organism selection in a biological waste treatment system provides an effective means of engineering process efficiency. Examples of applications of organism selection include control of filamentous organisms, biological nutrient removal, industrial waste treatment requiring the removal of specific substrates, and hazardous waste treatment. Inherently, full scale biological waste treatment systems are unsteady state systems due to the variations in the waste streams and mass flow rates of the substrates. Some systems, however, have the capacity to impose controlled selective pressures on the biological population by means of their operation. An example of such a systemmore » is the Sequencing Batch Reactor (SBR) which was the experimental system utilized in this research work. The concepts of organism selection were studied in detail for the biodegradation of a herbicide waste stream, with glyphosate as the target compound. The SBR provided a reactor configuration capable of exerting the necessary selective pressures to select and enrich for a glyphosate degrading population. Based on results for bench scale SBRs, a hypothesis was developed to explain population dynamics in glyphosate degrading systems.« less
Surveillance of work-related asthma in new york state.
Tice, Cori J; Cummings, Karen R; Gelberg, Kitty H
2010-04-01
The objective of this paper is to determine the percent of adults with asthma attributable to work and describe characteristics of the work-related asthma population in New York State. Sociodemographic and control characteristics of those with and without work-related asthma are compared. Data from three population-based surveys and one case-based surveillance system were analyzed. Work-relatedness of asthma was determined by self-report for the population-based surveys and by physician report for the case-based system. Self-reported sociodemographic and control characteristics were analyzed for the population-based surveys by work-relatedness. The percent of work-relatedness among adults with current asthma in New York State ranged from 10.6% to 44.5%. Significantly more adults with work-related asthma had poorly controlled asthma than those without work-related asthma. More adults with work-related asthma also tended to be employed in the manufacturing, educational services, and public administration industries than the general population. The most frequently reported exposure was dust. Adults with work-related asthma have decreased control and adverse socioeconomic impacts compared to those with asthma that is not work-related. Increased recognition and physician reporting is necessary to further prevent the impact of work-related exposures.
On estimation of time-dependent attributable fraction from population-based case-control studies.
Zhao, Wei; Chen, Ying Qing; Hsu, Li
2017-09-01
Population attributable fraction (PAF) is widely used to quantify the disease burden associated with a modifiable exposure in a population. It has been extended to a time-varying measure that provides additional information on when and how the exposure's impact varies over time for cohort studies. However, there is no estimation procedure for PAF using data that are collected from population-based case-control studies, which, because of time and cost efficiency, are commonly used for studying genetic and environmental risk factors of disease incidences. In this article, we show that time-varying PAF is identifiable from a case-control study and develop a novel estimator of PAF. Our estimator combines odds ratio estimates from logistic regression models and density estimates of the risk factor distribution conditional on failure times in cases from a kernel smoother. The proposed estimator is shown to be consistent and asymptotically normal with asymptotic variance that can be estimated empirically from the data. Simulation studies demonstrate that the proposed estimator performs well in finite sample sizes. Finally, the method is illustrated by a population-based case-control study of colorectal cancer. © 2017, The International Biometric Society.
Outlining a Population “at Risk” of Parkinson's Disease: Evidence from a Case-Control Study
Schirinzi, Tommaso; Martella, Giuseppina; D'Elia, Alessio; Di Lazzaro, Giulia; Imbriani, Paola; Madeo, Graziella; Monaco, Leonardo; Maltese, Marta
2016-01-01
The multifactorial pathogenesis of Parkinson's Disease (PD) requires a careful identification of populations “at risk” of developing the disease. In this case-control study we analyzed a large Italian population, in an attempt to outline general criteria to define a population “at risk” of PD. We enrolled 300 PD patients and 300 controls, gender and age matched, from the same urban geographical area. All subjects were interviewed on demographics, family history of PD, occupational and environmental toxicants exposure, smoking status, and alcohol consumption. A sample of 65 patients and 65 controls also underwent serum dosing of iron, copper, mercury, and manganese by means of Inductively Coupled-Plasma-Mass-Spectrometry (ICP-MS). Positive family history, toxicants exposure, non-current-smoker, and alcohol nonconsumer status occurred as significant risk factors in our population. The number of concurring risk factors overlapping in the same subject impressively increased the overall risk. No significant differences were measured in the metal serum levels. Our findings indicate that combination of three to four concurrent PD-risk factors defines a condition “at risk” of PD. A simple stratification, based on these questionnaires, might be of help in identifying subjects suitable for neuroprotective strategies. PMID:27651975
Dey, Snigdhadip; Bose, Joy; Joshi, Amitabh
2012-05-01
Density-dependent selection is expected to lead to population stability, especially if r and K tradeoff. Yet, there is no empirical evidence of adaptation to crowding leading to the evolution of stability. We show that populations of Drosophila ananassae selected for adaptation to larval crowding have higher K and lower r, and evolve greater stability than controls. We also show that increased population growth rates at high density can enhance stability, even in the absence of a decrease in r, by ensuring that the crowding adapted populations do not fall to very low sizes. We discuss our results in the context of traits known to have diverged between the selected and control populations, and compare our results with previous work on the evolution of stability in D. melanogaster. Overall, our results suggest that density-dependent selection may be an important factor promoting the evolution of relatively stable dynamics in natural populations.
Evidence that lake trout served as a buffer against sea lamprey predation on burbot in Lake Erie
Stapanian, M.A.; Madenjian, C.P.
2007-01-01
The population of burbot Lota lota in Lake Erie recovered during 1986–2003, mainly because of the control of sea lamprey Petromyzon marinus, which began in 1986. Burbot populations continued to grow during 1996–1998, when sea lamprey control was substantially reduced. We calculated mortality parameters for burbot in Lake Erie by estimating age at capture for 2,793 burbot caught in annual gill-net surveys of eastern Lake Erie from 1994 to 2003. Based on catch-curve analysis, annual mortality in Lake Erie during 1994–2003 was estimated as 33%. Annual mortality of the 1992 year-class of burbot was estimated as 30%. The mortality of burbot during the years of reduced sea lamprey control was not different from that during the 3 years preceding reduced control and was significantly lower than that during the entire portion of the time series in which full sea lamprey control was conducted. These results suggest that the reduction in sea lamprey control did not lead to increased burbot mortality. The catch per gill-net lift of large burbot (total length > 600 mm), the size preferred by sea lampreys, was lower than that of adult lake trout Salvelinus namaycush (age 5 and older; total length > 700 mm) before lampricide application was reduced. Although adult lake trout populations declined, the abundance of large burbot did not change during the period of reduced lampricide application. These results support a hypothesis that a healthy population of adult lake trout can serve as a buffer species, acting to reduce predation of burbot by sea lampreys when sea lamprey populations increase. Burbot attained sexual maturity at a relatively early age (3 or 4 years) and a total length (approximately 500 mm) that was smaller than the preferred prey size for sea lampreys. These characteristics and the buffering effect of the lake trout population enabled growth of the burbot population during the brief period when lamprey control was reduced.
USDA-ARS?s Scientific Manuscript database
We explored the population genetics of two European swallow-worts belonging to the Apocynaceae that have become established in the eastern United States and Canada. Population genetic data concerning both native and introduced populations are being used to pinpoint introduced population origin, and ...
The Preventive Control of Zoonotic Visceral Leishmaniasis: Efficacy and Economic Evaluation
Wu, Jianhong; Massad, Eduardo
2017-01-01
Zoonotic Visceral Leishmaniasis (ZVL) is one of the world's deadliest and neglected infectious diseases, according to World Health Organization. This disease is one of major human and veterinary medical significance. The sandfly and the reservoir in urban areas remain among the major challenges for the control activities. In this paper, we evaluated five control strategies (positive dog elimination, insecticide impregnated dog collar, dog vaccination, dog treatment, and sandfly population control), considering disease control results and cost-effectiveness. We elaborated a mathematical model based on a set of differential equations in which three populations were represented (human, dog, and sandfly). Humans and dogs were divided into susceptible, latent, clinically ill, and recovery categories. Sandflies were divided into noninfected, infected, and infective. As the main conclusions, the insecticide impregnated dog collar was the strategy that presented the best combination between disease control and cost-effectiveness. But, depending on the population target, the control results and cost-effectiveness of each strategy may differ. More and detailed studies are needed, specially one which optimizes the control considering more than one strategy in activity. PMID:28588642
The Preventive Control of Zoonotic Visceral Leishmaniasis: Efficacy and Economic Evaluation.
Shimozako, Helio Junji; Wu, Jianhong; Massad, Eduardo
2017-01-01
Zoonotic Visceral Leishmaniasis (ZVL) is one of the world's deadliest and neglected infectious diseases, according to World Health Organization. This disease is one of major human and veterinary medical significance. The sandfly and the reservoir in urban areas remain among the major challenges for the control activities. In this paper, we evaluated five control strategies (positive dog elimination, insecticide impregnated dog collar, dog vaccination, dog treatment, and sandfly population control), considering disease control results and cost-effectiveness. We elaborated a mathematical model based on a set of differential equations in which three populations were represented (human, dog, and sandfly). Humans and dogs were divided into susceptible, latent, clinically ill, and recovery categories. Sandflies were divided into noninfected, infected, and infective. As the main conclusions, the insecticide impregnated dog collar was the strategy that presented the best combination between disease control and cost-effectiveness. But, depending on the population target, the control results and cost-effectiveness of each strategy may differ. More and detailed studies are needed, specially one which optimizes the control considering more than one strategy in activity.
Sport hunting, predator control and conservation of large carnivores.
Packer, Craig; Kosmala, Margaret; Cooley, Hilary S; Brink, Henry; Pintea, Lilian; Garshelis, David; Purchase, Gianetta; Strauss, Megan; Swanson, Alexandra; Balme, Guy; Hunter, Luke; Nowell, Kristin
2009-06-17
Sport hunting has provided important economic incentives for conserving large predators since the early 1970's, but wildlife managers also face substantial pressure to reduce depredation. Sport hunting is an inherently risky strategy for controlling predators as carnivore populations are difficult to monitor and some species show a propensity for infanticide that is exacerbated by removing adult males. Simulation models predict population declines from even moderate levels of hunting in infanticidal species, and harvest data suggest that African countries and U.S. states with the highest intensity of sport hunting have shown the steepest population declines in African lions and cougars over the past 25 yrs. Similar effects in African leopards may have been masked by mesopredator release owing to declines in sympatric lion populations, whereas there is no evidence of overhunting in non-infanticidal populations of American black bears. Effective conservation of these animals will require new harvest strategies and improved monitoring to counter demands for predator control by livestock producers and local communities.
Life cycle and reproduction of house-dust mites: environmental factors influencing mite populations.
Hart, B J
1998-01-01
An understanding of the life cycle of house-dust mites, as well as environmental factors influencing mite populations, can be exploited in mite control. The most important limiting factor for house-dust-mite populations is air humidity. House-dust mites osmoregulate through the cuticle and therefore require a high ambient air humidity to prevent excessive water loss. In addition, the supracoxal glands actively take up ambient water vapour, and the protonynph stage of the life cycle is resistant to desiccation. Larger house-dust-mite populations are found when the absolute indoor air humidity is above 7 g/kg (45% relative humidity at 20 degrees C). Consequently, ventilation by air-conditioning systems is being developed as a means of control. A number of other aspects of the domestic environment are also being manipulated in an integrated approach to render the habitat less suitable for mites. The potential exists for developing models for house-dust mite populations, environmental characteristics, and the effects of various approaches to control.
Sport Hunting, Predator Control and Conservation of Large Carnivores
Packer, Craig; Kosmala, Margaret; Cooley, Hilary S.; Brink, Henry; Pintea, Lilian; Garshelis, David; Purchase, Gianetta; Strauss, Megan; Swanson, Alexandra; Balme, Guy; Hunter, Luke; Nowell, Kristin
2009-01-01
Sport hunting has provided important economic incentives for conserving large predators since the early 1970's, but wildlife managers also face substantial pressure to reduce depredation. Sport hunting is an inherently risky strategy for controlling predators as carnivore populations are difficult to monitor and some species show a propensity for infanticide that is exacerbated by removing adult males. Simulation models predict population declines from even moderate levels of hunting in infanticidal species, and harvest data suggest that African countries and U.S. states with the highest intensity of sport hunting have shown the steepest population declines in African lions and cougars over the past 25 yrs. Similar effects in African leopards may have been masked by mesopredator release owing to declines in sympatric lion populations, whereas there is no evidence of overhunting in non-infanticidal populations of American black bears. Effective conservation of these animals will require new harvest strategies and improved monitoring to counter demands for predator control by livestock producers and local communities. PMID:19536277
Li, Guoju; Wang, Hailing; Wang, Ke; Wang, Wenrui; Dong, Fen; Qian, Yonggang; Gong, Haiying; Xu, Guodong; Li, Yanlong; Pan, Li; Wang, Bin; Zhu, Guangjin; Shan, Guangliang
2016-04-01
Han and Mongolian populations constitute approximately 96% of the population of Inner Mongolia Autonomous Region, and the two ethnic groups have different genetic backgrounds and lifestyle. We aim to assess the prevalence, awareness, treatment, control, and related risk factors of hypertension among urban adults in Inner Mongolia, with the comparison of the differences between Mongolian and Han populations in this respect. Three thousand two hundred fifty-one individuals aged 20-80 years (2326 Han and 925 Mongolian) were selected using a multistage cluster sampling method from Inner Mongolia in 2014. The adjusted prevalence, awareness, treatment and control of hypertension were evaluated by the Logistic regression. In addition, possible interactions were also tested. When interactions were found significant, strata-specific analysis were performed. Multivariate logistic regression was used for estimating independent associations between risk factors and hypertension. The prevalence of hypertension was 27.47% for Han population, 31.46% for Mongolian population. The adjusted prevalence, awareness, treatment and control of hypertension were 26.45, 65.43, 78.24 and 48.28% in Han, and 31.30, 68.22, 85.57 and 50.55% in Mongolian, respectively. There was no significant difference in the adjusted awareness, treatment and control of hypertension among Mongolian and Han adult residents (all P >0.05). Lower prevalence of hypertension was associated with younger age and healthy weight in both Mongolian and Han adults. Within Han adults, high education, moderate physical activity and non-alcohol drinkers were additionally associated with lower prevalence of hypertension, whereas within Mongolian adults, lower prevalence was associated with being female. Among residents with medium education level, nondrinkers had 0.60 times lower odds of having hypertension than current drinkers (OR = 0.60, 95% CI: 0.44-0.82); among residents with high education level, nondrinkers has 0.65 times lower odds of having hypertension than current drinkers (OR = 0.65, 95% CI: 0.43-0.97). Mongolian population had a higher prevalence of hypertension than Han population. There were no significant difference between Mongolian and Han population in awareness, treatment and control of hypertension, which suggested that there was no difference between the two ethnicities in the distribution of health resources.
Phani, Nagaraja M; Guddattu, Vasudeva; Bellampalli, Ravishankara; Seenappa, Venu; Adhikari, Prabha; Nagri, Shivashankara K; D Souza, Sydney C; Mundyat, Gopinath P; Satyamoorthy, Kapaettu; Rai, Padmalatha S
2014-01-01
Potassium inwardly rectifying channel, subfamily J, member 11 (KCNJ11) gene have a key role in insulin secretion and is of substantial interest as a candidate gene for type 2 diabetes (T2D). The current work was performed to delineate the genetic influence of KCNJ11 polymorphisms on risk of T2D in South Indian population through case-control association study along with systematic review and meta-analysis. A case-control study of 400 T2D cases and controls of South Indian origin were performed to analyze the association of KCNJ11 polymorphisms (rs5219, rs5215, rs41282930, rs1800467) and copy number variations (CNV) on the risk of T2D. In addition a systematic review and meta-analysis for KCNJ11 rs5219 was conducted in 3,831 cases and 3,543 controls from 5 published reports from South-Asian population by searching various databases. Odds ratio with 95% confidence interval (CI) was used to assess the association strength. Cochran's Q, I2 statistics were used to study heterogeneity between the eligible studies. KCNJ11 rs5215, C-G-C-C haplotype and two loci analysis (rs5219 vs rs1800467) showed a significant association with T2D but CNV analysis did not show significant variation between T2D cases and control subjects. Lower age of disease onset (P = 0.04) and higher body mass index (BMI) (P = 0.04) were associated with rs5219 TT genotype in T2D patients. The meta-analysis of KCNJ11 rs5219 on South Asian population showed no association on susceptibility to T2D with an overall pooled OR = 0.98, 95% CI = 0.83-1.16. Stratification analysis showed East Asian population and global population were associated with T2D when compared to South Asians. KCNJ11 rs5219 is not independently associated with T2D in South-Indian population and our meta-analysis suggests that KCNJ11 polymorphism (rs5219) is associated with risk of T2D in East Asian population and global population but this outcome could not be replicated in South Asian sub groups.
Evans, T A
2001-12-01
Although mark-recapture protocols produce inaccurate population estimates of termite colonies, they might be employed to estimate a relative change in colony size. This possibility was tested using two Australian, mound-building, wood-eating, subterranean Coptotermes species. Three different toxicants delivered in baits were used to decrease (but not eliminate) colony size, and a single mark-recapture protocol was used to estimate pre- and postbaiting population sizes. For both species, the numbers of termites retrieved from bait stations varied widely, resulting in no significant differences in the numbers of termites sampled between treatments in either the pre- or postbaiting protocols. There were significantly fewer termites sampled in all treatments, controls included, in the postbaiting protocol compared with the pre-, suggesting a seasonal change in forager numbers. The comparison of population estimates shows a large decrease in toxicant treated colonies compared with little change in control colonies, which suggests that estimating the relative decline in population size using mark-recapture protocols might to be possible. However, the change in population estimate was due entirely to the significantly lower recapture rate in the control colonies relative to the toxicant treated colonies, as numbers of unmarked termites did not change between treatments. The population estimates should be treated with caution because low recapture rates produce dubious population estimates and, in some cases, postbaiting mark-recapture population estimates could be much greater than those at prebaiting, despite consumption of bait in sufficient quantities to cause population decline. A possible interaction between fat-stain markers and toxicants should be investigated if mark-recapture population estimates are used. Alternative methods of population change are advised, along with other indirect measures.
Efffect of Aeroallergen Sensitization on Asthma Control in ...
In African-American adolescents with persistent asthma, allergic profile predicted the likelihood of having poorly controlled asthma despite guidelines-directed therapies. Our results suggest that tree and weed pollen sensitization are independent risk factors for poorly controlled asthma in this at-risk population. The study examined African-American children with difficult to treat asthma. The findings suggest that in addition to guidelines-directed asthma therapies, targeting the allergic component, particularly tree and weed pollen, is critical to achieving optimal asthma control in this at-risk population.
Bernaitis, Nijole; Ching, Chi Keong; Chen, Liping; Hon, Jin Shing; Teo, Siew Chong; Davey, Andrew K; Anoopkumar-Dukie, Shailendra
2017-01-01
Warfarin reduces stroke risk in atrial fibrillation (AF) patients but requires ongoing monitoring. Time in therapeutic range (TTR) is used as a measure of warfarin control, with a TTR less than 60% associated with adverse patient outcomes. The Sex, Age, Medical history, Treatment, Tobacco use, Race (SAMe-TT 2 R 2 ) score has been identified as a model able to predict warfarin control, but this has been tested in mainly Caucasian populations. Therefore, the aim of this study was to determine the ability of the SAMe-TT 2 R 2 score to predict warfarin control in a Singaporean population consisting of Chinese, Malay, and Indian race. Retrospective data were collected from the National Heart Centre Singapore for AF patients receiving warfarin between January and June 2014. The TTR and the SAMe-TT 2 R 2 score were calculated for each patient. The 1137 non-valvular AF patients had a mean TTR of 58.0 ± 34.3% and a median SAMe-TT 2 R 2 score of 3. The categorized SAMe-TT 2 R 2 scores (2 versus >2) showed a significant reduction in mean TTR for the entire population (63.2% versus 55.8%, P = .0004) and also when categorized according to race for Chinese (62.7% versus 56.9%, P = .0075) and Malay (68.4% versus 50.6%, P = .0131) populations. The SAMe-TT 2 R 2 tool is effective in predicting warfarin control in a Singaporean population as patients with a score greater than 2 had poor control. The minimum score for non-Caucasian patients is 2; thus, in these patients, the presence of any additional risk factors identified in the SAMe-TT 2 R 2 tool categorizes them as unlikely to achieve adequate warfarin control and possible candidates for alternative anticoagulants. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.
34 CFR 300.28 - Local educational agency.
Code of Federal Regulations, 2014 CFR
2014-07-01
... legally constituted within a State for either administrative control or direction of, or to perform a... having administrative control and direction of a public elementary school or secondary school, including... population that is smaller than the student population of the LEA receiving assistance under the Act with the...
34 CFR 300.28 - Local educational agency.
Code of Federal Regulations, 2013 CFR
2013-07-01
... legally constituted within a State for either administrative control or direction of, or to perform a... having administrative control and direction of a public elementary school or secondary school, including... population that is smaller than the student population of the LEA receiving assistance under the Act with the...
34 CFR 300.28 - Local educational agency.
Code of Federal Regulations, 2012 CFR
2012-07-01
... legally constituted within a State for either administrative control or direction of, or to perform a... having administrative control and direction of a public elementary school or secondary school, including... population that is smaller than the student population of the LEA receiving assistance under the Act with the...
34 CFR 300.28 - Local educational agency.
Code of Federal Regulations, 2011 CFR
2011-07-01
... legally constituted within a State for either administrative control or direction of, or to perform a... having administrative control and direction of a public elementary school or secondary school, including... population that is smaller than the student population of the LEA receiving assistance under the Act with the...
Mass trapping for Anastrepha suspensa
USDA-ARS?s Scientific Manuscript database
Mass trapping has been found to be highly effective for control of pest fruit flies when populations are low and a highly effective lure is available for the target species. Successful population control through mass trapping is an indicator that attract-and-kill bait stations may be equally succes...
Irwin, Jodi A; Saunier, Jessica L; Strouss, Katharine M; Sturk, Kimberly A; Diegoli, Toni M; Just, Rebecca S; Coble, Michael D; Parson, Walther; Parsons, Thomas J
2007-06-01
In an effort to increase the quantity, breadth and availability of mtDNA databases suitable for forensic comparisons, we have developed a high-throughput process to generate approximately 5000 control region sequences per year from regional US populations, global populations from which the current US population is derived and global populations currently under-represented in available forensic databases. The system utilizes robotic instrumentation for all laboratory steps from pre-extraction through sequence detection, and a rigorous eight-step, multi-laboratory data review process with entirely electronic data transfer. Over the past 3 years, nearly 10,000 control region sequences have been generated using this approach. These data are being made publicly available and should further address the need for consistent, high-quality mtDNA databases for forensic testing.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Sen; Zhang, Wei; Lian, Jianming
This paper studies a multi-stage pricing problem for a large population of thermostatically controlled loads. The problem is formulated as a reverse Stackelberg game that involves a mean field game in the hierarchy of decision making. In particular, in the higher level, a coordinator needs to design a pricing function to motivate individual agents to maximize the social welfare. In the lower level, the individual utility maximization problem of each agent forms a mean field game coupled through the pricing function that depends on the average of the population control/state. We derive the solution to the reverse Stackelberg game bymore » connecting it to a team problem and the competitive equilibrium, and we show that this solution corresponds to the optimal mean field control that maximizes the social welfare. Realistic simulations are presented to validate the proposed methods.« less
Uncertainty, learning, and the optimal management of wildlife
Williams, B.K.
2001-01-01
Wildlife management is limited by uncontrolled and often unrecognized environmental variation, by limited capabilities to observe and control animal populations, and by a lack of understanding about the biological processes driving population dynamics. In this paper I describe a comprehensive framework for management that includes multiple models and likelihood values to account for structural uncertainty, along with stochastic factors to account for environmental variation, random sampling, and partial controllability. Adaptive optimization is developed in terms of the optimal control of incompletely understood populations, with the expected value of perfect information measuring the potential for improving control through learning. The framework for optimal adaptive control is generalized by including partial observability and non-adaptive, sample-based updating of model likelihoods. Passive adaptive management is derived as a special case of constrained adaptive optimization, representing a potentially efficient suboptimal alternative that nonetheless accounts for structural uncertainty.
Garcia, Rita de Cassia Maria; Calderón, Néstor; Ferreira, Fernando
2012-08-01
The objective of this study is to propose a generic program for the management of urban canine populations with suggestion of performance indicators. The following international guidelines on canine population management were revised and consolidated: World Health Organization, World Organisation for Animal Health, World Society for the Protection of Animals, International Companion Animal Management Coalition, and the Food and Agriculture Organization. Management programs should cover: situation diagnosis, including estimates of population size; social participation with involvement of various sectors in the planning and execution of strategies; educational actions to promote humane values, animal welfare, community health, and responsible ownership (through purchase or adoption); environmental and waste management to eliminate sources of food and shelter; registration and identification of animals; animal health care, reproductive control; prevention and control of zoonoses; control of animal commerce; management of animal behavior and adequate solutions for abandoned animals; and laws regulating responsible ownership, prevention of abandonment and zoonoses. To monitor these actions, four groups of indicators are suggested: animal population indicators, human/animal interaction indicators, public service indicators, and zoonosis indicators. The management of stray canine populations requires political, sanitary, ethologic, ecologic, and humanitarian strategies that are socially acceptable and environmentally sustainable. Such measures must also include the control of zoonoses such as rabies and leishmaniasis, considering the concept of "one health," which benefits both the animals and people in the community.
Impact of floating population on the epidemic of tuberculosis: a spatial analysis
NASA Astrophysics Data System (ADS)
Jia, Zhongwei; He, Xiaoxin; Zhao, Wenjuan; An, Yansheng; Cao, Wuchun; Li, Xiaowen
2007-06-01
According to the report issued by the Health Bureau of Beijing that the number of newly registered active pulmonary tuberculosis cases in floating population exceeded half of that in registered permanent residence in 2006. More attention has been paid to the tuberculosis of floating population. Materials and methods: The population data included in the studied was reported by the Beijing Police Bureau in 2004, and the case source from 2004 to 2006 was provided by Beijing Research Institute for TB Control. Two GIS-based methods have been used to detect the hot spots of tuberculosis in 18 districts of Beijing. Results: The distributions of hot spots of tuberculosis in Beijing are significantly associated with that of floating people. Most likely cluster from all population matches with those from floating population, which is stable from 2004 to 2006. Conclusion: The spatial analytical results indicated that the floating population has a drastic influence on the epidemic of tuberculosis in Beijing. The tuberculosis control measures should incorporate the effect of floating population.
The relationship of Asperger's syndrome to autism: a preliminary EEG coherence study.
Duffy, Frank H; Shankardass, Aditi; McAnulty, Gloria B; Als, Heidelise
2013-07-31
It has long been debated whether Asperger's Syndrome (ASP) should be considered part of the Autism Spectrum Disorders (ASD) or whether it constitutes a unique entity. The Diagnostic and Statistical Manual, fourth edition (DSM-IV) differentiated ASP from high functioning autism. However, the new DSM-5 umbrellas ASP within ASD, thus eliminating the ASP diagnosis. To date, no clear biomarkers have reliably distinguished ASP and ASD populations. This study uses EEG coherence, a measure of brain connectivity, to explore possible neurophysiological differences between ASP and ASD. Voluminous coherence data derived from all possible electrode pairs and frequencies were previously reduced by principal components analysis (PCA) to produce a smaller number of unbiased, data-driven coherence factors. In a previous study, these factors significantly and reliably differentiated neurotypical controls from ASD subjects by discriminant function analysis (DFA). These previous DFA rules are now applied to an ASP population to determine if ASP subjects classify as control or ASD subjects. Additionally, a new set of coherence based DFA rules are used to determine whether ASP and ASD subjects can be differentiated from each other. Using prior EEG coherence based DFA rules that successfully classified subjects as either controls or ASD, 96.2% of ASP subjects are classified as ASD. However, when ASP subjects are directly compared to ASD subjects using new DFA rules, 92.3% ASP subjects are identified as separate from the ASD population. By contrast, five randomly selected subsamples of ASD subjects fail to reach significance when compared to the remaining ASD populations. When represented by the discriminant variable, both the ASD and ASD populations are normally distributed. Within a control-ASD dichotomy, an ASP population falls closer to ASD than controls. However, when compared directly with ASD, an ASP population is distinctly separate. The ASP population appears to constitute a neurophysiologically identifiable, normally distributed entity within the higher functioning tail of the ASD population distribution. These results must be replicated with a larger sample given their potentially immense clinical, emotional and financial implications for affected individuals, their families and their caregivers.
The relationship of Asperger’s syndrome to autism: a preliminary EEG coherence study
2013-01-01
Background It has long been debated whether Asperger’s Syndrome (ASP) should be considered part of the Autism Spectrum Disorders (ASD) or whether it constitutes a unique entity. The Diagnostic and Statistical Manual, fourth edition (DSM-IV) differentiated ASP from high functioning autism. However, the new DSM-5 umbrellas ASP within ASD, thus eliminating the ASP diagnosis. To date, no clear biomarkers have reliably distinguished ASP and ASD populations. This study uses EEG coherence, a measure of brain connectivity, to explore possible neurophysiological differences between ASP and ASD. Methods Voluminous coherence data derived from all possible electrode pairs and frequencies were previously reduced by principal components analysis (PCA) to produce a smaller number of unbiased, data-driven coherence factors. In a previous study, these factors significantly and reliably differentiated neurotypical controls from ASD subjects by discriminant function analysis (DFA). These previous DFA rules are now applied to an ASP population to determine if ASP subjects classify as control or ASD subjects. Additionally, a new set of coherence based DFA rules are used to determine whether ASP and ASD subjects can be differentiated from each other. Results Using prior EEG coherence based DFA rules that successfully classified subjects as either controls or ASD, 96.2% of ASP subjects are classified as ASD. However, when ASP subjects are directly compared to ASD subjects using new DFA rules, 92.3% ASP subjects are identified as separate from the ASD population. By contrast, five randomly selected subsamples of ASD subjects fail to reach significance when compared to the remaining ASD populations. When represented by the discriminant variable, both the ASD and ASD populations are normally distributed. Conclusions Within a control-ASD dichotomy, an ASP population falls closer to ASD than controls. However, when compared directly with ASD, an ASP population is distinctly separate. The ASP population appears to constitute a neurophysiologically identifiable, normally distributed entity within the higher functioning tail of the ASD population distribution. These results must be replicated with a larger sample given their potentially immense clinical, emotional and financial implications for affected individuals, their families and their caregivers. PMID:23902729
Belinato, Thiago Affonso; Valle, Denise
2015-01-01
Several Aedes aegypti field populations are resistant to neurotoxic insecticides, mainly organophoshates and pyrethroids, which are extensively used as larvicides and adulticides, respectively. Diflubenzuron (DFB), a chitin synthesis inhibitor (CSI), was recently approved for use in drinking water, and is presently employed in Brazil for Ae. aegypti control, against populations resistant to the organophosphate temephos. However, tests of DFB efficacy against field Ae. aegypti populations are lacking. In addition, information regarding the dynamics of CSI resistance, and characterization of any potential fitness effects that may arise in conjunction with resistance are essential for new Ae. aegypti control strategies. Here, the efficacy of DFB was evaluated for two Brazilian Ae. aegypti populations known to be resistant to both temephos and the pyrethroid deltamethrin. Laboratory selection for DFB resistance was then performed over six or seven generations, using a fixed dose of insecticide that inhibited 80% of adult emergence in the first generation. The selection process was stopped when adult emergence in the diflubenzuron-treated groups was equivalent to that of the control groups, kept without insecticide. Diflubenzuron was effective against the two Ae. aegypti field populations evaluated, regardless of their resistance level to neurotoxic insecticides. However, only a few generations of DFB selection were sufficient to change the susceptible status of both populations to this compound. Several aspects of mosquito biology were affected in both selected populations, indicating that diflubenzuron resistance acquisition is associated with a fitness cost. We believe that these results can significantly contribute to the design of control strategies involving the use of insect growth regulators. PMID:26107715
Lima, Mauricio; Navarrete, Luis; González-Andujar, José Luis
2012-01-01
Pest control is one of the areas in which population dynamic theory has been successfully applied to solve practical problems. However, the links between population dynamic theory and model construction have been less emphasized in the management and control of weed populations. Most management models of weed population dynamics have emphasized the role of the endogenous process, but the role of exogenous variables such as climate have been ignored in the study of weed populations and their management. Here, we use long-term data (22 years) on two annual weed species from a locality in Central Spain to determine the importance of endogenous and exogenous processes (local and large-scale climate factors). Our modeling study determined two different feedback structures and climate effects in the two weed species analyzed. While Descurainia sophia exhibited a second-order feedback and low climate influence, Veronica hederifolia was characterized by a first-order feedback structure and important effects from temperature and rainfall. Our results strongly suggest the importance of theoretical population dynamics in understanding plant population systems. Moreover, the use of this approach, discerning between the effect of exogenous and endogenous factors, can be fundamental to applying weed management practices in agricultural systems and to controlling invasive weedy species. This is a radical change from most approaches currently used to guide weed and invasive weedy species managements.
Lima, Mauricio; Navarrete, Luis; González-Andujar, José Luis
2012-01-01
Pest control is one of the areas in which population dynamic theory has been successfully applied to solve practical problems. However, the links between population dynamic theory and model construction have been less emphasized in the management and control of weed populations. Most management models of weed population dynamics have emphasized the role of the endogenous process, but the role of exogenous variables such as climate have been ignored in the study of weed populations and their management. Here, we use long-term data (22 years) on two annual weed species from a locality in Central Spain to determine the importance of endogenous and exogenous processes (local and large-scale climate factors). Our modeling study determined two different feedback structures and climate effects in the two weed species analyzed. While Descurainia sophia exhibited a second-order feedback and low climate influence, Veronica hederifolia was characterized by a first-order feedback structure and important effects from temperature and rainfall. Our results strongly suggest the importance of theoretical population dynamics in understanding plant population systems. Moreover, the use of this approach, discerning between the effect of exogenous and endogenous factors, can be fundamental to applying weed management practices in agricultural systems and to controlling invasive weedy species. This is a radical change from most approaches currently used to guide weed and invasive weedy species managements. PMID:22272362
Revisiting the Basic Reproductive Number for Malaria and Its Implications for Malaria Control
Smith, David L; McKenzie, F. Ellis; Snow, Robert W; Hay, Simon I
2007-01-01
The prospects for the success of malaria control depend, in part, on the basic reproductive number for malaria, R 0. Here, we estimate R 0 in a novel way for 121 African populations, and thereby increase the number of R 0 estimates for malaria by an order of magnitude. The estimates range from around one to more than 3,000. We also consider malaria transmission and control in finite human populations, of size H. We show that classic formulas approximate the expected number of mosquitoes that could trace infection back to one mosquito after one parasite generation, Z 0(H), but they overestimate the expected number of infected humans per infected human, R 0(H). Heterogeneous biting increases R 0 and, as we show, Z 0(H), but we also show that it sometimes reduces R 0(H); those who are bitten most both infect many vectors and absorb infectious bites. The large range of R 0 estimates strongly supports the long-held notion that malaria control presents variable challenges across its transmission spectrum. In populations where R 0 is highest, malaria control will require multiple, integrated methods that target those who are bitten most. Therefore, strategic planning for malaria control should consider R 0, the spatial scale of transmission, human population density, and heterogeneous biting. PMID:17311470
Black Family Planning: Attitudes of Leaders and a General Sample.
ERIC Educational Resources Information Center
Harris, William G.; And Others
Attitudes of black leaders and a general black population sample toward birth control and family planning issues were "Pro Birth Control" and "Genocide Fears." The leaders questioned held positions in twenty national black organizations, while the general population samples were taken from Philadelphia, Pennsylvania, and Charlotte, North Carolina.…
34 CFR 303.23 - Local educational agency.
Code of Federal Regulations, 2012 CFR
2012-07-01
... legally constituted within a State for either administrative control or direction of, or to perform a... institution or agency having administrative control and direction of a public elementary school or secondary... population that is smaller than the student population of the LEA receiving assistance under the Act with the...
50 CFR 31.2 - Methods of surplus wildlife population control and disposal.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Methods of surplus wildlife population control and disposal. 31.2 Section 31.2 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM WILDLIFE SPECIES MANAGEMENT...
50 CFR 31.2 - Methods of surplus wildlife population control and disposal.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false Methods of surplus wildlife population control and disposal. 31.2 Section 31.2 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM WILDLIFE SPECIES MANAGEMENT...
50 CFR 31.2 - Methods of surplus wildlife population control and disposal.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Methods of surplus wildlife population control and disposal. 31.2 Section 31.2 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM WILDLIFE SPECIES MANAGEMENT...
50 CFR 31.2 - Methods of surplus wildlife population control and disposal.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Methods of surplus wildlife population control and disposal. 31.2 Section 31.2 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM WILDLIFE SPECIES MANAGEMENT...
50 CFR 31.2 - Methods of surplus wildlife population control and disposal.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Methods of surplus wildlife population control and disposal. 31.2 Section 31.2 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM WILDLIFE SPECIES MANAGEMENT...
USDA-ARS?s Scientific Manuscript database
Recent malaria vector control measures have considerably reduced indoor biting mosquito populations. However, reducing the outdoor biting populations remains a challenge because of the unavailability of appropriate lures to achieve this. This study sought to test the efficacy of plant-based syntheti...
Gao, Tianxiang; Wan, Zhenzhen; Song, Na; Zhang, Xiumei; Han, Zhiqiang
2014-12-01
A number of evolutionary mechanisms have been suggested for generating significant genetic structuring among marine fish populations in Northwestern Pacific. We used mtDNA control region to assess the factors in shaping the genetic structure of Japanese grenadier anchovy, Coilia nasus, an anadromous and estuarine coastal species, in Northwestern Pacific. Sixty seven individuals from four locations in Northwestern Pacific were sequenced for mitochondrial control region, detecting 61 haplotypes. The length of amplified control region varied from 677 to 754 bp. This length variability was due to the presence of varying numbers of a 38-bp tandemly repeated sequence. Two distinct lineages were detected, which might have diverged during Pleistocene low sea levels. There were strong differences in the geographical distribution of the two lineages. Analyses of molecular variance and the population statistic ΦST revealed significant genetic structure between China and Ariake Bay populations. Based on the frequency distribution of tandem repeat units, significant genetic differentiation was also detected between China and Ariake Bay populations. Isolation by distance seems to be the main factor driving present genetic structuring of C. nasus populations, indicating coastal dispersal pattern in this coastal species. Such an evolutionary process agrees well with some of the biological features characterizing this species.
Zhu, Jing; Fry, James D.
2018-01-01
The natural habitat of Drosophila melanogaster Meigen (Diptera: Drosophilidae) is fermenting fruits, which can be rich in ethanol. For unknown reasons, temperate populations of this cosmopolitan species have higher ethanol resistance than tropical populations. To determine whether this difference is accompanied by a parallel difference in preference for ethanol, we compared two European and two tropical African populations in feeding and oviposition preference for ethanol-supplemented medium. Although females of all populations laid significantly more eggs on medium with ethanol than on control medium, preference of European females for ethanol increased as ethanol concentration increased from 2 to 6%, whereas that of African females decreased. In feeding tests, African females preferred control medium over medium with 4% ethanol, whereas European females showed no preference. Males of all populations strongly preferred control medium. The combination of preference for ethanol in oviposition, and avoidance or neutrality in feeding, gives evidence that adults choose breeding sites with ethanol for the benefit of larvae, rather than for their own benefit. The stronger oviposition preference for ethanol of temperate than tropical females suggests that this benefit may be more important in temperate populations. Two possible benefits of ethanol for which there is some experimental evidence are cryoprotection and protection against natural enemies. PMID:29398715
Johnson, Nicholas S.; Swink, William D.; Brenden, Travis O.; Slade, Jeffrey W.; Steeves, Todd B.; Fodale, Michael F.; Jones, Michael L.
2014-01-01
Sea lamprey Petromyzon marinus control in the Great Lakes primarily involves application of lampricides to streams where larval production occurs to kill larvae prior to their metamorphosing and entering the lakes as parasites (juveniles). Because lampricides are not 100% effective, larvae that survive treatment maymetamorphose before streams are again treated. Larvae that survive treatment have not beenwidely studied, so their dynamics are notwell understood.Wetagged and released larvae in six Great Lake tributaries following lampricide treatment and estimated vital demographic rates using multistate tag-recovery models. Model-averaged larval survivals ranged from 56.8 to 57.6%. Model-averaged adult recovery rates, which were the product of juvenile survivals and adult capture probabilities, ranged from 6.8 to 9.3%. Using stochastic simulations, we estimated production of juvenile sea lampreys from a hypothetical population of treatment survivors under different growth conditions based on parameter estimates from this research. For fast-growing populations, juvenile production peaked 2 years after treatment. For slow-growing populations, juvenile production was approximately one-third that of fast-growing populations,with production not peaking until 4 years after treatment. Our results suggest that dynamics (i.e., survival, metamorphosis) of residual larval populations are very similar to those of untreated larval populations. Consequently, residual populations do not necessarily warrant special consideration for the purpose of sea lamprey control and can be ranked for treatment along with other populations. Consecutive lampricide treatments, which are under evaluation by the sea lamprey control program, would bemost effective for reducing juvenile production in large, fast-growing populations.
Hopper, Keith R
2003-01-01
During 1999-2001, ARS scientists published over 100 papers on more than 30 species of insect pest and 60 species of predator and parasitoid. These papers address issues crucial to the three strategies of biological control: conservation, augmentation and introduction. Conservation biological control includes both conserving extant populations of natural enemies by using relatively non-toxic pesticides and increasing the abundance of natural enemies in crops by providing or improving refuges for population growth and dispersal into crops. ARS scientists have been very active in determining the effects of pesticides on beneficial arthropods and in studying movement of natural enemies from refuges into crops. Augmentation involves repeated releases of natural enemies in the field, which can be inoculative or inundative. Inoculative releases are used to initiate self-propagating populations at times or in places where they would be slow to colonize. ARS scientists have studied augmentative biological control of a variety of pest insects. The targets are mostly pests in annual crops or other ephemeral habitats, where self-reproducing populations of natural enemies are not sufficiently abundant early enough to keep pest populations in check. ARS research in augmentative biological control centers on methods for rearing large numbers of healthy, effective natural enemies and for releasing them where and when they are needed at a cost less than the value of the reduction in damage to the crop. ARS scientists have researched various aspects of introductions of exotic biological control agents against a diversity of pest insects. The major issues in biological control introductions are accurate identification and adequate systematics of both natural enemies and target pests, exploration for natural enemies, predicting the success of candidates for introduction and the likelihood of non-target impacts, quarantine and rearing methods, and post-introduction evaluation of establishment, control and non-target impacts. ARS scientists have published research on several general issues in biological control. Among the most important are the mechanisms affecting mate- and host-finding and host specificity.
Application of three controls optimally in a vector-borne disease - a mathematical study
NASA Astrophysics Data System (ADS)
Kar, T. K.; Jana, Soovoojeet
2013-10-01
We have proposed and analyzed a vector-borne disease model with three types of controls for the eradication of the disease. Four different classes for the human population namely susceptible, infected, recovered and vaccinated and two different classes for the vector populations namely susceptible and infected are considered. In the first part of our analysis the disease dynamics are described for fixed controls and some inferences have been drawn regarding the spread of the disease. Next the optimal control problem is formulated and solved considering control parameters as time dependent. Different possible combination of controls are used and their effectiveness are compared by numerical simulation.
Russel, M G V M; Ryan, B M; Dagnelie, P C; de Rooij, M; Sijbrandij, J; Feleus, A; Hesselink, M; Muris, J W; Stockbrugger, R
2003-03-01
The majority of patients with inflammatory bowel disease (IBD) have a normal life expectancy and therefore should not be weighted when applying for life assurance. There is scant literature on this topic. In this study our aim was to document and compare the incidence of difficulties in application for life and medical insurance in a population based cohort of IBD patients and matched population controls. A population based case control study of 1126 IBD patients and 1723 controls. Based on a detailed questionnaire, the frequency and type of difficulties encountered when applying for life and medical insurance in matched IBD and control populations were appraised. In comparison with controls, IBD patients had an 87-fold increased risk of encountering difficulties when applying for life assurance (odds ratio (OR) 87 (95% confidence interval (CI) 31-246)), with a heavily weighted premium being the most common problem. Patients of high educational status, with continuous disease activity, and who smoked had the highest odds of encountering such problems. Medical insurance difficulties were fivefold more common in IBD patients compared with controls (OR 5.4 (95% CI 2.3-13)) although no specific disease or patient characteristics were identified as associated with such difficulties. This is the first detailed case control study that has investigated insurance difficulties among IBD patients. Acquiring life and medical insurance constituted a major problem for IBD patients in this study. These results are likely to be more widely representative given that most insurance companies use international guidelines for risk assessment. In view of the recent advances in therapy and promising survival data on IBD patients, evidence based guidelines for risk assessment of IBD patients by insurance companies should be drawn up to prevent possible discriminatory practices.
Russel, M G V M; Ryan, B M; Dagnelie, P C; de Rooij, M; Sijbrandij, J; Feleus, A; Hesselink, M; Muris, J W; Stockbrugger, R
2003-01-01
Background and aims: The majority of patients with inflammatory bowel disease (IBD) have a normal life expectancy and therefore should not be weighted when applying for life assurance. There is scant literature on this topic. In this study our aim was to document and compare the incidence of difficulties in application for life and medical insurance in a population based cohort of IBD patients and matched population controls. Methods: A population based case control study of 1126 IBD patients and 1723 controls. Based on a detailed questionnaire, the frequency and type of difficulties encountered when applying for life and medical insurance in matched IBD and control populations were appraised. Results: In comparison with controls, IBD patients had an 87-fold increased risk of encountering difficulties when applying for life assurance (odds ratio (OR) 87 (95% confidence interval (CI) 31–246)), with a heavily weighted premium being the most common problem. Patients of high educational status, with continuous disease activity, and who smoked had the highest odds of encountering such problems. Medical insurance difficulties were fivefold more common in IBD patients compared with controls (OR 5.4 (95% CI 2.3–13)) although no specific disease or patient characteristics were identified as associated with such difficulties. Conclusions: This is the first detailed case control study that has investigated insurance difficulties among IBD patients. Acquiring life and medical insurance constituted a major problem for IBD patients in this study. These results are likely to be more widely representative given that most insurance companies use international guidelines for risk assessment. In view of the recent advances in therapy and promising survival data on IBD patients, evidence based guidelines for risk assessment of IBD patients by insurance companies should be drawn up to prevent possible discriminatory practices. PMID:12584216
Addressing the Social Determinants of Health to Reduce Tobacco-Related Disparities
Garrett, Bridgette E.; Dube, Shanta R.; Babb, Stephen; McAfee, Tim
2016-01-01
Introduction Comprehensive tobacco prevention and control efforts that include implementing smoke-free air laws, increasing tobacco prices, conducting hard-hitting mass media campaigns, and making evidence-based cessation treatments available are effective in reducing tobacco use in the general population. However, if these interventions are not implemented in an equitable manner, certain population groups may be left out causing or exacerbating disparities in tobacco use. Disparities in tobacco use have, in part, stemmed from inequities in the way tobacco control policies and programs have been adopted and implemented to reach and impact the most vulnerable segments of the population that have the highest rates of smokings (e.g., those with lower education and incomes). Methods Education and income are the 2 main social determinants of health that negatively impact health. However, there are other social determinants of health that must be considered for tobacco control policies to be effective in reducing tobacco-related disparities. This article will provide an overview of how tobacco control policies and programs can address key social determinants of health in order to achieve equity and eliminate disparities in tobacco prevention and control. Results Tobacco control policy interventions can be effective in addressing the social determinants of health in tobacco prevention and control to achieve equity and eliminate tobacco-related disparities when they are implemented consistently and equitably across all population groups. Conclusions Taking a social determinants of health approach in tobacco prevention and control will be necessary to achieve equity and eliminate tobacco-related disparities. PMID:25516538
Demarzo, Marcelo; Montero-Marin, Jesus; Puebla-Guedea, Marta; Navarro-Gil, Mayte; Herrera-Mercadal, Paola; Moreno-González, Sergio; Calvo-Carrión, Sandra; Bafaluy-Franch, Laura; Garcia-Campayo, Javier
2017-01-01
Background: Many attempts have been made to abbreviate mindfulness programmes in order to make them more accessible for general and clinical populations while maintaining their therapeutic components and efficacy. The aim of this study was to assess the efficacy of an 8-week mindfulness-based intervention (MBI) programme and a 4-week abbreviated version for the improvement of well-being in a non-clinical population. Method: A quasi-experimental, controlled, pilot study was conducted with pre-post and 6-month follow-up measurements and three study conditions (8- and 4-session MBI programmes and a matched no-treatment control group, with a sample of 48, 46, and 47 participants in each condition, respectively). Undergraduate students were recruited, and mindfulness, positive and negative affect, self-compassion, resilience, anxiety, and depression were assessed. Mixed-effects multi-level analyses for repeated measures were performed. Results: The intervention groups showed significant improvements compared to controls in mindfulness and positive affect at the 2- and 6-month follow-ups, with no differences between 8- vs. 4-session programmes. The only difference between the abbreviated MBI vs. the standard MBI was found in self-kindness at 6 months, favoring the standard MBI. There were marginal differences in anxiety between the controls vs. the abbreviated MBI, but there were differences between the controls vs. the standard MBI at 2- and 6-months, with higher levels in the controls. There were no differences in depression between the controls vs. the abbreviated MBI, but differences were found between the controls vs. the standard MBI at 2- and 6-months, favoring the standard MBI. There were no differences with regard to negative affect and resilience. Conclusion: To our knowledge, this is the first study to directly investigate the efficacy of a standard 8-week MBI and a 4-week abbreviated protocol in the same population. Based on our findings, both programmes performed better than controls, with similar effect size (ES). The efficacy of abbreviated mindfulness programmes may be similar to that of a standard MBI programme, making them potentially more accessible for a larger number of populations. Nevertheless, further studies with more powerful designs to compare the non-inferiority of the abbreviated protocol and addressing clinical populations are warranted. Clinical Trials.gov Registration ID: NCT02643927.
Demarzo, Marcelo; Montero-Marin, Jesus; Puebla-Guedea, Marta; Navarro-Gil, Mayte; Herrera-Mercadal, Paola; Moreno-González, Sergio; Calvo-Carrión, Sandra; Bafaluy-Franch, Laura; Garcia-Campayo, Javier
2017-01-01
Background: Many attempts have been made to abbreviate mindfulness programmes in order to make them more accessible for general and clinical populations while maintaining their therapeutic components and efficacy. The aim of this study was to assess the efficacy of an 8-week mindfulness-based intervention (MBI) programme and a 4-week abbreviated version for the improvement of well-being in a non-clinical population. Method: A quasi-experimental, controlled, pilot study was conducted with pre-post and 6-month follow-up measurements and three study conditions (8- and 4-session MBI programmes and a matched no-treatment control group, with a sample of 48, 46, and 47 participants in each condition, respectively). Undergraduate students were recruited, and mindfulness, positive and negative affect, self-compassion, resilience, anxiety, and depression were assessed. Mixed-effects multi-level analyses for repeated measures were performed. Results: The intervention groups showed significant improvements compared to controls in mindfulness and positive affect at the 2- and 6-month follow-ups, with no differences between 8- vs. 4-session programmes. The only difference between the abbreviated MBI vs. the standard MBI was found in self-kindness at 6 months, favoring the standard MBI. There were marginal differences in anxiety between the controls vs. the abbreviated MBI, but there were differences between the controls vs. the standard MBI at 2- and 6-months, with higher levels in the controls. There were no differences in depression between the controls vs. the abbreviated MBI, but differences were found between the controls vs. the standard MBI at 2- and 6-months, favoring the standard MBI. There were no differences with regard to negative affect and resilience. Conclusion: To our knowledge, this is the first study to directly investigate the efficacy of a standard 8-week MBI and a 4-week abbreviated protocol in the same population. Based on our findings, both programmes performed better than controls, with similar effect size (ES). The efficacy of abbreviated mindfulness programmes may be similar to that of a standard MBI programme, making them potentially more accessible for a larger number of populations. Nevertheless, further studies with more powerful designs to compare the non-inferiority of the abbreviated protocol and addressing clinical populations are warranted. Clinical Trials.gov Registration ID: NCT02643927 PMID:28848465
Baumgartner, Kendra; Smith, Richard F; Bettiga, Larry
2005-03-01
Arbuscular mycorrhizal (AM) fungi naturally colonize grapevines in California vineyards. Weed control and cover cropping may affect AM fungi directly, through destruction of extraradical hyphae by soil disruption, or indirectly, through effects on populations of mycorrhizal weeds and cover crops. We examined the effects of weed control (cultivation, post-emergence herbicides, pre-emergence herbicides) and cover crops (Secale cereale cv. Merced rye, x Triticosecale cv.Trios 102) on AM fungi in a Central Coast vineyard. Seasonal changes in grapevine mycorrhizal colonization differed among weed control treatments, but did not correspond with seasonal changes in total weed frequency. Differences in grapevine colonization among weed control treatments may be due to differences in mycorrhizal status and/or AM fungal species composition among dominant weed species. Cover crops had no effect on grapevine mycorrhizal colonization, despite higher spring spore populations in cover cropped middles compared to bare middles. Cover crops were mycorrhizal and shared four AM fungal species (Glomus aggregatum, G. etunicatum, G. mosseae, G. scintillans) in common with grapevines. Lack of contact between grapevine roots and cover crop roots may have prevented grapevines from accessing higher spore populations in the middles.
Sletvold, Nina; Dahlgren, Johan P; Oien, Dag-Inge; Moen, Asbjørn; Ehrlén, Johan
2013-09-01
Climate change is expected to influence the viability of populations both directly and indirectly, via species interactions. The effects of large-scale climate change are also likely to interact with local habitat conditions. Management actions designed to preserve threatened species therefore need to adapt both to the prevailing climate and local conditions. Yet, few studies have separated the direct and indirect effects of climatic variables on the viability of local populations and discussed the implications for optimal management. We used 30 years of demographic data to estimate the simultaneous effects of management practice and among-year variation in four climatic variables on individual survival, growth and fecundity in one coastal and one inland population of the perennial orchid Dactylorhiza lapponica in Norway. Current management, mowing, is expected to reduce competitive interactions. Statistical models of how climate and management practice influenced vital rates were incorporated into matrix population models to quantify effects on population growth rate. Effects of climate differed between mown and control plots in both populations. In particular, population growth rate increased more strongly with summer temperature in mown plots than in control plots. Population growth rate declined with spring temperature in the inland population, and with precipitation in the coastal population, and the decline was stronger in control plots in both populations. These results illustrate that both direct and indirect effects of climate change are important for population viability and that net effects depend both on local abiotic conditions and on biotic conditions in terms of management practice and intensity of competition. The results also show that effects of management practices influencing competitive interactions can strongly depend on climatic factors. We conclude that interactions between climate and management should be considered to reliably predict future population viability and optimize conservation actions. © 2013 John Wiley & Sons Ltd.
Chiu, Tzu-I; Spencer, Gale A
2010-09-01
To assess the relationship between perceived social control/personal control and functional health status among older adults in rural and urban Taiwan. The ageing of the population is poised to emerge as a preeminent worldwide phenomenon. It is assumed that even though older adults experience many decades of autonomy and independence, the potential for illness or bodily decline will induce a serious reduction in the level of perceived control in older adult populations. This is a descriptive correlational study using a secondary data base, Social Environment and Biomarkers of Aging Study. Social Environment and Biomarkers of Aging Study is a nationally representative study of health outcomes in the Taiwanese population. Both perceived levels of social control and personal control had a statistically significant relationship with functional health status. Functional health status was significantly higher for urban older adults than their rural counterparts. Personal control and social control were both found to be predictors of functional health status. Major findings are supported by previous studies. Nurses should create programs and plan activities to assist older adults to enhance their perceptions of social control or personal control in order to improve the health status of older adults and minimize associated health care costs. © 2009 Blackwell Publishing Ltd.
Population growth and global security
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mumford, S.
A new threat to international and domestic security has emerged in the past three decades: uncontrolled world population growth. Current world population growth control efforts are ineffective. Unchecked growth will threaten global security by depleting food, energy, and other resources. Immigration is another complicating factor that is straining the carrying capacity of some overpopulated regions. Barriers to effective action include the desire of decision-makers to avoid the controversy of abortion and the role of the Catholic church in lobbying against birth control. (3 graphs, 12 photos, 2 tables)
Environmental DNA calibration study. Interim technical review report
Baerwaldt, K.; Bartron, Meredith L.; Schilling, K.; Lee, Debbie; Russo, Edmond; Estes, Trudy; Fischer, Richard; Fleming, Beth; Guilfoyle, Michael P.; Kilgore, K. Jack; Lance, Richard; Perkins, Edward; Schultz, Martin; Smith, David; Amberg, Jon J.; Chapman, Duane C.; Gaikowski, Mark P.; Klymus, Katy E.; Richter, Catherine A.
2014-01-01
Should a sustainable Asian carp population become established in the Great Lakes, native fish populations, as well as many threatened or endangered plant/animal species populations, could be impacted. In response to this threat, the Asian Carp Regional Control Committee (ACRCC) was formed in part to coordinate efforts to understand and organize against the Asian carp threat. The Asian Carp Control Strategy Framework (2012a) outlined major tasks to be completed for a better understanding of factors related to the advance of Asian carp populations towards the Great Lakes. In addition, the ACRCC formed the Monitoring and Rapid Response Workgroup to address Asian carp monitoring and removal (ACRCC 2012b).
Native intra- and inter-specific reactions may cause the paradox of pest control with harvesting.
Seno, Hiromi
2010-05-01
We analyse a general time-discrete mathematical model of host-parasite population dynamics with harvesting, in which the host can be regarded as a pest. We harvest a portion of the host population at a moment in each year. Our model involves the density effect on the host population. We investigate the condition in which the harvesting of the host results in a paradoxical increase of its equilibrium population size. Our results imply that for a family of pest-enemy systems, the paradox of pest control could be caused essentially by the interspecific relationship and the intraspecific density effect.
Liao, Su-Su; Zhang, Qing-Ning; Hou, Lei
2012-10-01
Epidemiology, as the study of occurrence and distribution of diseases or health events in specified populations and the application of the study to control health problems, is not just a method to study determinants of diseases at individual level through analysis of mass data based on individuals. To achieve the aims on the control of health problems in specified populations, Epidemiology should be public health-oriented to reduce incidence, prevalence and mortality, and should include study on determinants at the population level. Interdisplinarity and systems science will facilitate the breakthrough in improving health of the populations.
Life-History Traits of Spodoptera frugiperda Populations Exposed to Low-Dose Bt Maize
Sousa, Fernanda F.; Mendes, Simone M.; Santos-Amaya, Oscar F.; Araújo, Octávio G.; Oliveira, Eugenio E.
2016-01-01
Exposure to Bacillus thuringiensis (Bt) toxins in low- and moderate-dose transgenic crops may induce sublethal effects and increase the rate of Bt resistance evolution, potentially compromising control efficacy against target pests. We tested this hypothesis using the fall armyworm Spodoptera frugiperda, a major polyphagous lepidopteran pest relatively tolerant to Bt notorious for evolving field-relevant resistance to single-gene Bt maize. Late-instar larvae were collected from Bt Cry1Ab and non-Bt maize fields in five locations in Brazil, and their offspring was compared for survival, development, and population growth in rearing environment without and with Cry1Ab throughout larval development. Larval survival on Cry1Ab maize leaves varied from 20 to 80% among the populations. Larvae reared on Cry1Ab maize had seven-day delay in development time in relation to control larvae, and such delay was shorter in offspring of armyworms from Cry1Ab maize. Population growth rates were 50–70% lower for insects continuously exposed to Cry1Ab maize relative to controls, showing the population-level effect of Cry1Ab, which varied among the populations and prior exposure to Cry1Ab maize in the field. In three out of five populations, armyworms derived from Bt maize reared on Cry1Ab maize showed higher larval weight, faster larval development and better reproductive performance than the armyworms derived from non-Bt maize, and one of these populations showed better performance on both Cry1Ab and control diets, indicating no fitness cost of the resistance trait. Altogether, these results indicate that offspring of armyworms that developed on field-grown, single-gene Bt Cry1Ab maize had reduced performance on Cry1Ab maize foliage in two populations studied, but in other three populations, these offspring had better overall performance on the Bt maize foliage than that of the armyworms from non-Bt maize fields, possibly because of Cry1Ab resistance alleles in these populations. Implications of these findings for resistance management of S. frugiperda in Bt crops are discussed. PMID:27243977
Taylor, Louise H.; Wallace, Ryan M.; Balaram, Deepashree; Lindenmayer, Joann M.; Eckery, Douglas C.; Mutonono-Watkiss, Beryl; Parravani, Ellie; Nel, Louis H.
2017-01-01
Free-roaming dogs and rabies transmission are integrally linked across many low-income countries, and large unmanaged dog populations can be daunting to rabies control program planners. Dog population management (DPM) is a multifaceted concept that aims to improve the health and well-being of free-roaming dogs, reduce problems they may cause, and may also aim to reduce dog population size. In theory, DPM can facilitate more effective rabies control. Community engagement focused on promoting responsible dog ownership and better veterinary care could improve the health of individual animals and dog vaccination coverage, thus reducing rabies transmission. Humane DPM tools, such as sterilization, could theoretically reduce dog population turnover and size, allowing rabies vaccination coverage to be maintained more easily. However, it is important to understand local dog populations and community attitudes toward them in order to determine whether and how DPM might contribute to rabies control and which DPM tools would be most successful. In practice, there is very limited evidence of DPM tools achieving reductions in the size or turnover of dog populations in canine rabies-endemic areas. Different DPM tools are frequently used together and combined with rabies vaccinations, but full impact assessments of DPM programs are not usually available, and therefore, evaluation of tools is difficult. Surgical sterilization is the most frequently documented tool and has successfully reduced dog population size and turnover in a few low-income settings. However, DPM programs are mostly conducted in urban settings and are usually not government funded, raising concerns about their applicability in rural settings and sustainability over time. Technical demands, costs, and the time necessary to achieve population-level impacts are major barriers. Given their potential value, we urgently need more evidence of the effectiveness of DPM tools in the context of canine rabies control. Cheaper, less labor-intensive tools for dog sterilization will be extremely valuable in realizing the potential benefits of reduced population turnover and size. No one DPM tool will fit all situations, but if DPM objectives are achieved dog populations may be stabilized or even reduced, facilitating higher dog vaccination coverages that will benefit rabies elimination efforts. PMID:28740850
Life-History Traits of Spodoptera frugiperda Populations Exposed to Low-Dose Bt Maize.
Sousa, Fernanda F; Mendes, Simone M; Santos-Amaya, Oscar F; Araújo, Octávio G; Oliveira, Eugenio E; Pereira, Eliseu J G
2016-01-01
Exposure to Bacillus thuringiensis (Bt) toxins in low- and moderate-dose transgenic crops may induce sublethal effects and increase the rate of Bt resistance evolution, potentially compromising control efficacy against target pests. We tested this hypothesis using the fall armyworm Spodoptera frugiperda, a major polyphagous lepidopteran pest relatively tolerant to Bt notorious for evolving field-relevant resistance to single-gene Bt maize. Late-instar larvae were collected from Bt Cry1Ab and non-Bt maize fields in five locations in Brazil, and their offspring was compared for survival, development, and population growth in rearing environment without and with Cry1Ab throughout larval development. Larval survival on Cry1Ab maize leaves varied from 20 to 80% among the populations. Larvae reared on Cry1Ab maize had seven-day delay in development time in relation to control larvae, and such delay was shorter in offspring of armyworms from Cry1Ab maize. Population growth rates were 50-70% lower for insects continuously exposed to Cry1Ab maize relative to controls, showing the population-level effect of Cry1Ab, which varied among the populations and prior exposure to Cry1Ab maize in the field. In three out of five populations, armyworms derived from Bt maize reared on Cry1Ab maize showed higher larval weight, faster larval development and better reproductive performance than the armyworms derived from non-Bt maize, and one of these populations showed better performance on both Cry1Ab and control diets, indicating no fitness cost of the resistance trait. Altogether, these results indicate that offspring of armyworms that developed on field-grown, single-gene Bt Cry1Ab maize had reduced performance on Cry1Ab maize foliage in two populations studied, but in other three populations, these offspring had better overall performance on the Bt maize foliage than that of the armyworms from non-Bt maize fields, possibly because of Cry1Ab resistance alleles in these populations. Implications of these findings for resistance management of S. frugiperda in Bt crops are discussed.
Romero, Alvaro; Anderson, Troy D
2016-05-01
The rapid increase of bed bug populations resistant to pyrethroids demands the development of novel control tactics. Products combining pyrethroids and neonicotinoids have become very popular for bed bug control in the United States, but there are concerns about evolution of resistance to these compounds. Laboratory assays were used to measure the toxicity of topical applications of four neonicotinoids to a susceptible population and three pyrethroid-resistant populations. Activity of esterases, glutathione S-transferases, and cytochrome P450s of all strains was also evaluated. High levels of resistance to four neonicotinoids, acetamiprid, imidacloprid, dinotefuran, and thiamethoxam, relative to the susceptible Fort Dix population, were detected in populations collected from human dwellings in Cincinnati and Michigan. Because activity of detoxifying enzymes was increased in these two populations, our results suggest that these enzymes have some involvement in neonicotinoid resistance, but other resistance mechanisms might be involved as well. Detection of high levels of resistance to neonicotinoids further limits the options for chemical control of bed bugs. Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by US Government employees and is in the public domain in the US.
Dong, Fen; Wang, Dingming; Pan, Li; Yu, Yangwen; Wang, Ke; Li, Ling; Wang, Li; Liu, Tao; Zeng, Xianjia; Sun, Liangxian; Zhu, Guangjin; Feng, Kui; Zhang, Biao; Xu, Ke; Pang, Xinglong; Chen, Ting; Pan, Hui; Ma, Jin; Zhong, Yong; Ping, Bo; Shan, Guangliang
2016-02-19
Hypertension is highly prevalent in low-income population. This study aims to investigate ethnic disparities in hypertension and identify modifiable factors related to its occurrence and control in developing regions in South China. Blood pressure was measured in the Bouyei and Han populations during a community-based health survey in Guizhou, 2012. A multistage stratified sampling method was adopted to recruit Bouyei and Han aged from 20 to 80 years. Taking mixed effects into consideration, multilevel logistic models with random intercept were used for data analysis. The prevalence rates of hypertension were 35.3% for the Bouyei and 33.7% for the Han. Among the hypertensive participants, 30.1% of the Bouyei and 40.2% of the Han were aware of their hypertensive conditions, 19.7% of the Bouyei and 31.1% of the Han were receiving treatment, and only 3.6% of the Bouyei and 9.9% of the Han had their blood pressure under control. Age-sex standardized rates of awareness, treatment, and control were consistently lower in the Bouyei than the Han. Such ethnic disparities were more evident in the elderly population. Avoidance of excessive alcohol consumption and better education were favorable lifestyle for reduction in risk of hypertension. Moderate physical activity improved control of hypertension in Bouyei patients under treatment. Conclusively, hypertension awareness, treatment, and control were substantially lower in Bouyei than Han, particularly in the elderly population. Such ethnic disparities indicate that elderly Bouyei population should be targeted for tailored interventions in the future.
Components of Standing Postural Control Evaluated in Pediatric Balance Measures: A Scoping Review.
Sibley, Kathryn M; Beauchamp, Marla K; Van Ooteghem, Karen; Paterson, Marie; Wittmeier, Kristy D
2017-10-01
To identify measures of standing balance validated in pediatric populations, and to determine the components of postural control captured in each tool. Electronic searches of MEDLINE, Embase, and CINAHL databases using key word combinations of postural balance/equilibrium, psychometrics/reproducibility of results/predictive value of tests, and child/pediatrics; gray literature; and hand searches. Inclusion criteria were measures with a stated objective to assess balance, with pediatric (≤18y) populations, with at least 1 psychometric evaluation, with at least 1 standing task, with a standardized protocol and evaluation criteria, and published in English. Two reviewers independently identified studies for inclusion. There were 21 measures included. Two reviewers extracted descriptive characteristics, and 2 investigators independently coded components of balance in each measure using a systems perspective for postural control, an established framework for balance in pediatric populations. Components of balance evaluated in measures were underlying motor systems (100% of measures), anticipatory postural control (72%), static stability (62%), sensory integration (52%), dynamic stability (48%), functional stability limits (24%), cognitive influences (24%), verticality (9%), and reactive postural control (0%). Assessing children's balance with valid and comprehensive measures is important for ensuring development of safe mobility and independence with functional tasks. Balance measures validated in pediatric populations to date do not comprehensively assess standing postural control and omit some key components for safe mobility and independence. Existing balance measures, that have been validated in adult populations and address some of the existing gaps in pediatric measures, warrant consideration for validation in children. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Campo-Duarte, Doris E; Vasilieva, Olga; Cardona-Salgado, Daiver; Svinin, Mikhail
2018-06-01
Wolbachia-based biocontrol has recently emerged as a potential method for prevention and control of dengue and other vector-borne diseases. Major vector species, such as Aedes aegypti females, when deliberately infected with Wolbachia become less capable of getting viral infections and transmitting the virus to human hosts. In this paper, we propose an explicit sex-structured population model that describes an interaction of uninfected (wild) male and female mosquitoes and those deliberately infected with wMelPop strain of Wolbachia in the same locality. This particular strain of Wolbachia is regarded as the best blocker of dengue and other arboviral infections. However, wMelPop strain of Wolbachia also causes the loss of individual fitness in Aedes aegypti mosquitoes. Our model allows for natural introduction of the decision (or control) variable, and we apply the optimal control approach to simulate wMelPop Wolbachia infestation of wild Aedes aegypti populations. The control action consists in continuous periodic releases of mosquitoes previously infected with wMelPop strain of Wolbachia in laboratory conditions. The ultimate purpose of control is to find a tradeoff between reaching the population replacement in minimum time and with minimum cost of the control effort. This approach also allows us to estimate the number of Wolbachia-carrying mosquitoes to be released in day-by-day control action. The proposed method of biological control is safe to human health, does not contaminate the environment, does not make harm to non-target species, and preserves their interaction with mosquitoes in the ecosystem.
Gay, Isabel C; Tran, Duong T; Cavender, Adriana C; Weltman, Robin; Chang, Jennifer; Luckenbach, Estelle; Tribble, Gena D
2014-07-01
In the Mexican-American population, the prevalence of Type 2 diabetes mellitus (T2DM) is as high as 50% of the population. This randomized controlled clinical trial was designed to elucidate how treatment of periodontal disease affects HbA1c values in this population. One hundred and fifty-four T2DM patients with periodontal disease were enrolled in the study. The test group was treated with scaling and root planing (SRP); the control group received oral hygiene instructions. At baseline and 4-6 weeks after therapy, a complete periodontal examination was performed. Blood was collected at baseline and 4 months later for HbA1c levels. One hundred and twenty-six individuals completed the study. Baseline mean ± SD HbA1c for the test and control groups were 9.0 ± 2.3% and 8.4 ± 2.0% respectively. Non-significant difference in HbA1c reductions (0.6 ± 2.1% and 0.3 ± 1.7%) was found between test and control groups at 4 months. Comparisons of the periodontal clinical parameters between the test and control groups found significant differences with improved results in the test subjects. No statistically significant differences were found in the changes of HbA1c levels between test and control groups. Non-surgical periodontal therapy improved the magnitude of change in periodontal parameters as compared to the control subjects. ClinicalTrials.gov Identifier: NCT01128374. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
The Education of Population Scientists.
ERIC Educational Resources Information Center
Malcolm, Janet M.; Cargille, Charles M.
Population science, a combination of natural science, social science, and management science, deals with the phenomena associated with the human population size. Subjects include the rates of change of the sizes of the various subsets of the human population, the causes and results of those changes, the societal pressures for control of population…
Controlling Population with Pollution
ERIC Educational Resources Information Center
Browne, Joseph
2010-01-01
Population models are often discussed in algebra, calculus, and differential equations courses. In this article we will use the human population of the world as our application. After quick looks at two common models we'll investigate more deeply a model which incorporates the negative effect that accumulated pollution may have on population.
Possible mechanisms of mammalian immunocontraception.
Barber, M R; Fayrer-Hosken, R A
2000-03-01
Ecological and conservation programs in ecosystems around the world have experienced varied success in population management. One of the greatest problems is that human expansion has led to the shrinking of wildlife habitat and, as a result, the overpopulation of many different species has occurred. The pressures exerted by the increased number of animals has caused environmental damage. The humane and practical control of these populations has solicited the scientific community to arrive at a safe, effective, and cost-efficient means of population control. Immunocontraception using zona pellucida antigens, specifically porcine zona pellucida (pZP), has become one of the most promising population control tools in the world today, with notable successes in horses and elephants. A conundrum has risen where pZP, a single vaccine, successfully induces an immunocontraceptive effect in multiple species of mammals. This review describes the most current data pertaining to the mammalian zona pellucida and immunocontraception, and from these studies, we suggest several potential mechanisms of immunocontraception.
Miralles, Laura; Dopico, Eduardo; Devlo-Delva, Floriaan; Garcia-Vazquez, Eva
2016-09-15
Early detection of dangerous exotic species is crucial for stopping marine invasions. The New Zealand pygmy mussel Xenostrobus securis is a problematic species in coasts of temperate regions in the northern hemisphere. In this study we have controlled a population of this invader that recently expanded in a north Iberian estuary with both a participatory approach involving researchers and citizens, and employing a sensitive eDNA-based tool to monitor the population expansion in the estuary. Results demonstrate successful eradication of pygmy mussels in the outer part of the estuary with citizen science and the practical utility of eDNA for controlling biological invasions. Copyright © 2016 Elsevier Ltd. All rights reserved.
Bharati, Minu; Saha, Dhiraj
2017-06-01
Mosquitoes belonging to Aedes genus, Aedes aegypti and Aedes albopictus transmit many globally important arboviruses including Dengue (DENV) and Chikungunya (CHIKV). Vector control with the use of insecticide remains the suitable method of choice to stop the transmission of these diseases. However, vector control throughout the world is failing to achieve its target results because of the worldwide development of insecticide resistance in mosquitoes. To assess the insecticide susceptibility status of Aedes albopictus from northern part of West Bengal, the susceptibility of eight different Aedes albopictus populations were tested against a commonly used larvicide (temephos) and some adulticides (malathion, deltamethrin and lambda cyhalothrin) along with the major insecticide detoxifying enzymes' activity in them. Through this study, it was revealed that most of the populations were found susceptible to temephos except Nagrakata (NGK) and Siliguri (SLG), which showed both a higher resistance ratio (RR 99 ) and a lower susceptibility, thereby reflecting the development of resistance against temephos in them. However, all tested adulticides caused 100% mortality in all the population implying their potency in control of this mosquito in this region of India. Through the study of carboxylesterase activity, it was revealed that the NGK population showed a 9.6 fold higher level of activity than susceptible population. The same population also showed a lower level of susceptibility and a higher resistance ratio (RR 99 ), indicating a clear correlation between susceptibility to temephos and carboxylesterase enzymes' activity in this population. This preliminary data reflects that the NGK population is showing a trend towards resistance development and with time, there is possibility that this resistance phenomenon will spread to other populations. With the recurrence of dengue and chikungunya, this data on insecticide susceptibility status of Aedes albopictus could help the authorities engaged in vector control programmes to formulate effective measures against this mosquito in this region. Copyright © 2017 Elsevier B.V. All rights reserved.
Genetic differentiation among North Atlantic killer whale populations.
Foote, Andrew D; Vilstrup, Julia T; De Stephanis, Renaud; Verborgh, Philippe; Abel Nielsen, Sandra C; Deaville, Robert; Kleivane, Lars; Martín, Vidal; Miller, Patrick J O; Oien, Nils; Pérez-Gil, Monica; Rasmussen, Morten; Reid, Robert J; Robertson, Kelly M; Rogan, Emer; Similä, Tiu; Tejedor, Maria L; Vester, Heike; Víkingsson, Gísli A; Willerslev, Eske; Gilbert, M Thomas P; Piertney, Stuart B
2011-02-01
Population genetic structure of North Atlantic killer whale samples was resolved from differences in allele frequencies of 17 microsatellite loci, mtDNA control region haplotype frequencies and for a subset of samples, using complete mitogenome sequences. Three significantly differentiated populations were identified. Differentiation based on microsatellite allele frequencies was greater between the two allopatric populations than between the two pairs of partially sympatric populations. Spatial clustering of individuals within each of these populations overlaps with the distribution of particular prey resources: herring, mackerel and tuna, which each population has been seen predating. Phylogenetic analyses using complete mitogenomes suggested two populations could have resulted from single founding events and subsequent matrilineal expansion. The third population, which was sampled at lower latitudes and lower density, consisted of maternal lineages from three highly divergent clades. Pairwise population differentiation was greater for estimates based on mtDNA control region haplotype frequencies than for estimates based on microsatellite allele frequencies, and there were no mitogenome haplotypes shared among populations. This suggests low or no female migration and that gene flow was primarily male mediated when populations spatially and temporally overlap. These results demonstrate that genetic differentiation can arise through resource specialization in the absence of physical barriers to gene flow. © 2010 Blackwell Publishing Ltd.
Building robust functionality in synthetic circuits using engineered feedback regulation.
Chen, Susan; Harrigan, Patrick; Heineike, Benjamin; Stewart-Ornstein, Jacob; El-Samad, Hana
2013-08-01
The ability to engineer novel functionality within cells, to quantitatively control cellular circuits, and to manipulate the behaviors of populations, has many important applications in biotechnology and biomedicine. These applications are only beginning to be explored. In this review, we advocate the use of feedback control as an essential strategy for the engineering of robust homeostatic control of biological circuits and cellular populations. We also describe recent works where feedback control, implemented in silico or with biological components, was successfully employed for this purpose. Copyright © 2013 Elsevier Ltd. All rights reserved.
Yanomamo ecology, population control, and their relationship to slash and burn agriculture.
Owl, M Y
1976-01-01
Population control among the Yanomamo tribe of the Amazonian tropical rainforest is studied. 25% of male deaths are due to warfare. A male-female balance is achieved by the practice of infantcide, especially among female infants. The male:female ratio among the under-15 age group is 135:100, belying the tribe's contention that neither sex is more likely to be killed than the other. The major population controlffactor, however, is disease with about 54.2% of adult deaths due to malaria, and other communicable disease accounting for 11.7%. Other population controls are abortion and postnatal sex taboos, although the latter is for the most part overruled by the practice of infanticide for any child born while a previous child is still nursing. The intense intervillage warfare is increased by the shortage of women, resulting from female infanticide combined with polygamy and marriage alliances in which even unborn females are promised. Because there is war, male children are preferred and the cycle continues. Other observers, however, feel that the constant warfare is part of the need for new garden sites brought about by reliance on slash and burn agriculture. The author believes the shortage of women is just a side effect of population control occasioned by a protein shortage.
Ritchie, Scott A; van den Hurk, Andrew F; Smout, Michael J; Staunton, Kyran M; Hoffmann, Ary A
2018-03-01
Historically, sustained control of Aedes aegypti, the vector of dengue, chikungunya, yellow fever, and Zika viruses, has been largely ineffective. Subsequently, two novel 'rear and release' control strategies utilizing mosquitoes infected with Wolbachia are currently being developed and deployed widely. In the incompatible insect technique, male Aedes mosquitoes, infected with Wolbachia, suppress populations through unproductive mating. In the transinfection strategy, both male and female Wolbachia-infected Ae. aegypti mosquitoes rapidly infect the wild population with Wolbachia, blocking virus transmission. It is critical to monitor the long-term stability of Wolbachia in host populations, and also the ability of this bacterium to continually inhibit virus transmission. Ongoing release and monitoring programs must be future-proofed should political support weaken when these vectors are successfully controlled. Copyright © 2017 Elsevier Ltd. All rights reserved.
USDA-ARS?s Scientific Manuscript database
Mosquito control reduces populations of mosquitoes to minimize the risk of mosquito-borne diseases. As part of an integrated approach to mosquito control, application of adulticides can be effective in rapidly reducing mosquito populations during times of high arbovirus transmission. However, impact...
USDA-ARS?s Scientific Manuscript database
Insect pest control programs incorporating the sterile insect technique (SIT) rely on the mass production and release of sterilized insects to reduce the wild-type population through infertile matings. Most effective programs release only males to avoid any crop damage caused by female fruit flies o...
The Vatican & Population Growth Control: Why an American Confrontation?
ERIC Educational Resources Information Center
Mumford, Stephen D.
1983-01-01
The Vatican, because of its position on population growth, threatens the security of all nations. Catholic countries with right-wing dictatorships cannot confront the Vatican on family planning and survive. U.S. Catholics must confront the Vatican on this issue. American lay Catholics must break the American church away from the Vatican control.…
USDA-ARS?s Scientific Manuscript database
Demographic models are a powerful means of identifying vulnerable life stages of pest species and assessing the potential effectiveness of various management approaches in reducing pest population growth and spread. In a biological control context, such models can be used to focus foreign explorati...
Introduction: Unbiased geocoding of maternal residence is critical to the success of an ongoing population-based case-control study of exposure to five criteria air pollutants and the risk of selected birth defects in seven Texas counties between 1997 and 2000. The geocoded res...
Curry, S J; Grothaus, L; McBride, C
1997-01-01
An intrinsic-extrinsic model of motivation for smoking cessation is extended to a population-based sample of smokers (N = 1,137), using a previously validated Reasons for Quitting (RFQ) scale. Psychometric evaluation of the RFQ replicated the model that includes health concerns and self-control as intrinsic motivation dimensions and immediate reinforcement and social influence as extrinsic motivation dimensions. Compared to volunteers, the population-based sample of smokers reported equivalent health concerns, lower self-control, and higher social influence motivation for cessation. Within the population-based sample, women compared to men were less motivated to quit by health concerns and more motivated by immediate reinforcement; smokers above age 55 expressed lower health concerns and higher self-control motivation than smokers below age 55. Higher baseline levels of intrinsic relative to extrinsic motivation were associated with more advanced stages of readiness to quit smoking and successful smoking cessation at a 12-month follow-up. Among continuing smokers, improvement in stage of readiness to quit over time was associated with significant increases in health concerns and self-control motivation.
A new study of China's population control during the past ten years.
Wei, J
1989-02-01
This paper summarizes the control of population in China in the past 10 years and the changes that are occurring. Recently, an increase in the number of family members has directly influenced socioeconomic status by increasing family income and improving living conditions. Rural families have no incentives to control the number of children born. The cyclic effect of the 1962-73 baby boom is also causing a recent surge in population. China has studied these problems and has taken the following measures: new family planning systems have been established; population has been controlled macroscopically and flexibility is allowed at an individual level; governmental family planning organizations have been set up and financed; family planning education has been increased; family planning services have been enforced; incentives and restrictions have been implemented. China must work as a whole to enact and enforce these policies. Families must show restraint in childbearing. The only way for this to be accomplished is by decreasing the socioeconomic incentives to have children. Finally, reforms should be in tune with changing situations.
Health education campaign on population control: lessons from Iran.
Montazeri, A
1995-11-01
A descriptive study was carried out in Tehran, the capital of Iran, to investigate a health education campaign on population control. A sample of 68 adults aged 20 to 40 years participated in the study. Each respondent was shown a picture of the campaign. They then filled in a short questionnaire. The main objectives of the study were to measure recall rates and to assess attitude of the subjects. The study results show that recall rates were high (78%), 68% of respondents claimed that the campaign is likely to change their attitudes towards population control, and 87% of participants perceived the main idea of the campaign correctly. The study findings show that there are some significant associations between demographic variables (marital status, having child or not) and perception of the campaign. These may lead health educators and health promoters to communicate more effectively and efficiently in the context of family planning. In countries with a large number of young people, health education campaigns on population control with respect to social values of each society and moral considerations are recommended.
Wolff, Jonci Nikolai; Gemmell, Neil J; Tompkins, Daniel M; Dowling, Damian K
2017-01-01
Pests are a global threat to biodiversity, ecosystem function, and human health. Pest control approaches are thus numerous, but their implementation costly, damaging to non-target species, and ineffective at low population densities. The Trojan Female Technique (TFT) is a prospective self-perpetuating control technique that is species-specific and predicted to be effective at low densities. The goal of the TFT is to harness naturally occurring mutations in the mitochondrial genome that impair male fertility while having no effect on females. Here, we provide proof-of-concept for the TFT, by showing that introduction of a male fertility-impairing mtDNA haplotype into replicated populations of Drosophila melanogaster causes numerical population suppression, with the magnitude of effect positively correlated with its frequency at trial inception. Further development of the TFT could lead to establishing a control strategy that overcomes limitations of conventional approaches, with broad applicability to invertebrate and vertebrate species, to control environmental and economic pests. DOI: http://dx.doi.org/10.7554/eLife.23551.001 PMID:28467301
Rossow, H; Ollgren, J; Klemets, P; Pietarinen, I; Saikku, J; Pekkanen, E; Nikkari, S; Syrjälä, H; Kuusi, M; Nuorti, J P
2014-10-01
Few population-based data are available on factors associated with pneumonic and ulceroglandular type B tularaemia. We conducted a case-control study during a large epidemic in 2000. Laboratory-confirmed case patients were identified through active surveillance and matched control subjects (age, sex, residency) from the national population information system. Data were collected using a self-administered questionnaire. A conditional logistic regression model addressing missing data with Bayesian full-likelihood modelling included 227 case patients and 415 control subjects; reported mosquito bites [adjusted odds ratio (aOR) 9·2, 95% confidence interval (CI) 4·4-22, population-attributable risk (PAR) 82%] and farming activities (aOR 4·3, 95% CI 2·5-7·2, PAR 32%) were independently associated with ulceroglandular tularaemia, whereas exposure to hay dust (aOR 6·6, 95% CI 1·9-25·4, PAR 48%) was associated with pneumonic tularaemia. Although the bulk of tularaemia type B disease burden is attributable to mosquito bites, risk factors for ulceroglandular and pneumonic forms of tularaemia are different, enabling targeting of prevention efforts accordingly.
Utilizing population controls in rare-variant case-parent association tests.
Jiang, Yu; Satten, Glen A; Han, Yujun; Epstein, Michael P; Heinzen, Erin L; Goldstein, David B; Allen, Andrew S
2014-06-05
There is great interest in detecting associations between human traits and rare genetic variation. To address the low power implicit in single-locus tests of rare genetic variants, many rare-variant association approaches attempt to accumulate information across a gene, often by taking linear combinations of single-locus contributions to a statistic. Using the right linear combination is key-an optimal test will up-weight true causal variants, down-weight neutral variants, and correctly assign the direction of effect for causal variants. Here, we propose a procedure that exploits data from population controls to estimate the linear combination to be used in an case-parent trio rare-variant association test. Specifically, we estimate the linear combination by comparing population control allele frequencies with allele frequencies in the parents of affected offspring. These estimates are then used to construct a rare-variant transmission disequilibrium test (rvTDT) in the case-parent data. Because the rvTDT is conditional on the parents' data, using parental data in estimating the linear combination does not affect the validity or asymptotic distribution of the rvTDT. By using simulation, we show that our new population-control-based rvTDT can dramatically improve power over rvTDTs that do not use population control information across a wide variety of genetic architectures. It also remains valid under population stratification. We apply the approach to a cohort of epileptic encephalopathy (EE) trios and find that dominant (or additive) inherited rare variants are unlikely to play a substantial role within EE genes previously identified through de novo mutation studies. Copyright © 2014 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.
Controlling range expansion in habitat networks by adaptively targeting source populations.
Hock, Karlo; Wolff, Nicholas H; Beeden, Roger; Hoey, Jessica; Condie, Scott A; Anthony, Kenneth R N; Possingham, Hugh P; Mumby, Peter J
2016-08-01
Controlling the spread of invasive species, pests, and pathogens is often logistically limited to interventions that target specific locations at specific periods. However, in complex, highly connected systems, such as marine environments connected by ocean currents, populations spread dynamically in both space and time via transient connectivity links. This results in nondeterministic future distributions of species in which local populations emerge dynamically and concurrently over a large area. The challenge, therefore, is to choose intervention locations that will maximize the effectiveness of the control efforts. We propose a novel method to manage dynamic species invasions and outbreaks that identifies the intervention locations most likely to curtail population expansion by selectively targeting local populations most likely to expand their future range. Critically, at any point during the development of the invasion or outbreak, the method identifies the local intervention that maximizes the long-term benefit across the ecosystem by restricting species' potential to spread. In so doing, the method adaptively selects the intervention targets under dynamically changing circumstances. To illustrate the effectiveness of the method we applied it to controlling the spread of crown-of-thorns starfish (Acanthaster sp.) outbreaks across Australia's Great Barrier Reef. Application of our method resulted in an 18-fold relative improvement in management outcomes compared with a random targeting of reefs in putative starfish control scenarios. Although we focused on applying the method to reducing the spread of an unwanted species, it can also be used to facilitate the spread of desirable species through connectivity networks. For example, the method could be used to select those fragments of habitat most likely to rebuild a population if they were sufficiently well protected. © 2016 Society for Conservation Biology.
Torres, A K; Escartín, N; Monzó, C; Guzmán, C; Ferrer, I; González-Muñoz, C; Peña, P; Monzó, V; Marcaida, G; Rodríguez-López, R
To describe the populational distribution of the UGT1A1*28 variant (genetic variant code rs8175347) located in the promotor of the UGT gene and correlate its genotypes with the results of the fasting test, as well as its relationship with the biochemical disorder of Gilbert's syndrome (GS) in a Valencian population. We studied the prevalence of the genotypes (TA) 6/6 (TA) 6/7 and (TA) 7/7 of the deleterious variant rs8175347 in 144 patients with hyperbilirubinemia, 38 of whom had previously undergone the fasting test to diagnose GS, and in 150 control patients. By analysing the genomic region of the TATA box of the UGT1A1 gene promotor using Sanger sequencing, we established the correlation between the rs8175347 genotypes and the fasting test results and with the patients' biochemical disorders. The rate of heterozygosity of allele (TA) 7 in the control population was 32% and increased to 87.59% among the patients with suspected GS. The rate of genotype TA 7/7 was 81.94% among the patients with hyperbilirubinemia, compared with 11.33% in the control patients. The fasting test showed a 15.79% rate of false negatives and a 5.26% rate of false positives. The high frequency of allele (TA) 7 among the Valencian control population, almost double the 5% reported for European control patients, confirms the high rate of GS reported in the Spanish population, without observing significant differences between the geographical ends of the country. The efficacy and reliability of the fasting test for the diagnosis of GS is questionable. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Medicina Interna (SEMI). All rights reserved.
The association between the SLC6A3 VNTR 9-repeat allele and alcoholism-a meta-analysis.
Du, Yanlei; Nie, Yuqiang; Li, Yuyuan; Wan, Yu-Jui Y
2011-09-01
Dopamine transporter gene (SLC6A3) represents a promising candidate involved in the development of alcoholism. This study aimed to explore the association between the 9-repeat allele (A9) of a 40-bp variable number tandem repeat (VNTR) polymorphism in the 3' un-translated region (3' UTR) of the SLC6A3 gene and alcoholism. The SLC6A3 VNTR was genotyped by PCR in unrelated Mexican Americans including 337 controls and 365 alcoholics. Pearson's chi-square test or Fisher's exact test was used to compare the genotype and allele distribution. Meta-analyses were performed for population-based case-control association studies of the SLC6A3 VNTR polymorphism with alcoholism. Data were analyzed under random effect models with the Comprehensive Meta-analysis (v.2) statistical software package. In Mexican Americans, no significant difference was found in allele and genotype distribution between controls and alcoholics or between controls and alcoholics with alcohol withdrawal seizure (AWS) or delirium tremens (DT) (unadjusted p > 0.05). A total of 13 research articles were included in the meta-analyses. No significant difference of the SLC6A3 VNTR A9 was noted between controls and alcoholics at the genotypic and allelic level when all ethnic populations, only Caucasian populations, or only Asian populations were considered (p > 0.05). Significant associations were observed between SLC6A3 VNTR A9 and alcoholics with AWS or DT at the genotypic as well as allelic level when all ethnic populations or only Caucasian populations were considered (p < 0.05, OR 1.5-2.1). Meta-analyses suggest a possible association between the SLC6A3 VNTR A9 and alcoholic subgroup with AWS or DT. 2011 by the Research Society on Alcoholism.
van Hest, N A; Aldridge, R W; de Vries, G; Sandgren, A; Hauer, B; Hayward, A; Arrazola de Oñate, W; Haas, W; Codecasa, L R; Caylà, J A; Story, A; Antoine, D; Gori, A; Quabeck, L; Jonsson, J; Wanlin, M; Orcau, Å; Rodes, A; Dedicoat, M; Antoun, F; van Deutekom, H; Keizer, St; Abubakar, I
2014-03-06
In low-incidence countries in the European Union (EU), tuberculosis (TB) is concentrated in big cities, especially among certain urban high-risk groups including immigrants from TB high-incidence countries, homeless people, and those with a history of drug and alcohol misuse. Elimination of TB in European big cities requires control measures focused on multiple layers of the urban population. The particular complexities of major EU metropolises, for example high population density and social structure, create specific opportunities for transmission, but also enable targeted TB control interventions, not efficient in the general population, to be effective or cost effective. Lessons can be learnt from across the EU and this consensus statement on TB control in big cities and urban risk groups was prepared by a working group representing various EU big cities, brought together on the initiative of the European Centre for Disease Prevention and Control. The consensus statement describes general and specific social, educational, operational, organisational, legal and monitoring TB control interventions in EU big cities, as well as providing recommendations for big city TB control, based upon a conceptual TB transmission and control model.
Operational-scale application of entomopathogenic fungi for control of Sahelian grasshoppers
Kooyman, C.; Bateman, R. P.; Langewald, J.; Lomer, C. J.; Ouambama, Z.; Thomas, M. B.
1997-01-01
Locusts and grasshoppers regularly threaten agricultural production across large parts of the developed and developing worlds. Recent concerns over the health and environmental impacts of standard chemical control measures have led to a demand for alternative, more environmentally benign control technologies. Here we present the results of a field study to investigate the potential of inundative biological control for control of grasshoppers in the Sahelian region of Africa. The biocontrol agent was an oil-based biopesticide formulation of a naturally occurring entomopathogenic fungus, Metarhizium flavoviride. This was applied at a rate of 2l ha-1 to a total area of 150 ha using standard equipment normally used for the application of chemical pesticides. Twenty-one days after application, an 80 per cent reduction in grasshopper populations was recorded in treated plots, relative to control populations in equivalent unsprayed areas. We think that this is the first operational-scale application of a biopesticide to demonstrate significant population reductions of key Sahelian grasshopper pests. This represents a substantial development in locust and grasshopper control, and should open the way for a new era of integrated control strategies where reliance on conventional chemicals is reduced.
Implementation of China's population policy.
Qian, X Z
1983-05-01
On July 1, 1982 China's 3rd national population census reported the population of the 29 provinces, municipalities, and autonomous regions on the mainland at 1,008,175,288, showing a net increase of 460,000,000 or 84% over the 548,000,000 recorded at the end of 1949. At this time China's population is about 1/4 of the world. Its population policy must conform to her national conditions and will be successful only to the extent that it does so. Discussion focuses on the main features of China's population policy. In 1953 the State Council instructed the Ministry of Health to support birth control by providing contraceptives. It also ratified provisions concerning contraception and induced abortions. In 1962 the State Council issued "Instructions on Conscientious Advocacy of Family Planning." China not only advocates and publicized family planning but also takes specific measures. Special administrative organizations were established in 1964 to oversee scientific research, production, and supply of contraceptives and to provide couples of childbearing age with free contraceptives. An all round attack on family planning work in 1966 led to unchecked childbirth resulting in rapid population growth. In 1971 Premier Zhou Enlai reiterated the importance of population control in 1971 and asked that it be incorporated into the 4th Five Year Plan for the development of the national economy. Family planning was incorporated into the Constitution in 1978. China's 20 years of experiences with family planning suggest that a country's population policy becomes effective only with repeated efforts. The 10-year period of turmoil undermined the enforcement of the population policy. Recently the State Family Planning Commission organized a nationwide fertility survey which indicated tremendous successes for China's population control drive. The total fertility rate dropped from 5.29 in the 1950s to 2.63 in the 1980s. The population census shows that the momentum of China's population growth cannot be checked without strict measures because the population is characterized by a huge base figure, a young age composition, and a fertility rate much higher than a population replacement level. China's population policy is formulated in line with her national conditions. Specific provisions for family planning reflect different ways to deal with different people.
Experimental introduction of a microsporidian into a wild population of Culex pipiens fatigans Wied
Reynolds, D. G.
1972-01-01
Chemical control of C. p. fatigans frequently fails because the mosquito rapidly develops resistance to insecticides. A possible alternative or complementary method is biological control, including the introduction of pathogens. The microsporidian Plistophora culicis was known to infect readily and have an adverse effect on C. p. fatigans populations in the laboratory, so an attempt was made to introduce and establish this pathogen in a wild population of the mosquito on the Pacific island of Nauru. Two years after introduction the pathogen was still present in the wild population. However, the infection rate was similar to that found in naturally occurring infections in other mosquitos and is almost certainly not high enough to affect a natural population of C. p. fatigans adversely. PMID:4538542
Anderson, D P; McMurtrie, P; Edge, K-A; Baxter, P W J; Byrom, A E
2016-12-01
Successful pest-mammal eradications from remote islands have resulted in important biodiversity benefits. Near-shore islands can also serve as refuges for native biota but require ongoing effort to maintain low-pest or pest-free status. Three management options are available in the presence of reinvasion risk: (1) control-to-zero density, in which immigration may occur but reinvaders are removed; (2) sustained population suppression (to relatively low numbers); or (3) no action. Biodiversity benefits can result from options one and two. The management challenge is to make evidence-based decisions on the selection of an appropriate objective and to identify a financially feasible control strategy that has a high probability of success. This requires understanding the pest species population dynamics and how it will respond to a range of potential management strategies, each with an associated financial cost. We developed a two-stage modeling approach that consisted of (1) Bayesian inferential modeling to estimate parameters for a model of pest population dynamics and control, and (2) a forward projection model to simulate a range of plausible management scenarios and quantify the probability of obtaining zero density within four years. We applied the model to an ongoing, six-year trapping program to control stoats (Mustela erminea) on Resolution Island, New Zealand. Zero density has not yet been achieved. Results demonstrate that management objectives were impeded by a combination of a highly fecund population, insufficient trap attractiveness, and a substantial proportion of the population that did not enter traps. Immigration is known to occur because the founding population arrived on the island by swimming from the mainland. However, immigration rate during this study was indistinguishable from zero. The forward projection modeling showed that control-to-zero density was feasible but required greater than a two-fold budget increase to intensify the trapping rate relative to population growth. The two-stage modeling provides the foundation for a management program in which broad-scale trials of additional trapping effort or improved trap lures would test model predictions and increase our understanding of system dynamics. © 2016 by the Ecological Society of America.
Bunten, H; Liang, W J; Pounder, D J; Seneviratne, C; Osselton, D
2011-09-01
Methadone is used worldwide for the treatment of heroin addiction; however, fatal poisonings are increasingly reported. The prevalence of CYP2B6 and μ-opioid receptor (OPRM1) gene variations were examined between a postmortem population where the deaths were associated with methadone and a live nondrug-using control population using Taqman™ SNP Genotyping assays. The CYP2B6*6 allele was higher in the postmortem population, but the difference was not significant (P = 0.92). The CYP2B6 T750C promoter variation was similar in frequency for both populations. Linkage between T750C and CYP2B6*6 was identified for both populations (P < 0.01). The prevalence of the OPRM1 A118G variation was significantly higher in the control population (P = 0.0046), which might indicate a protective mechanism against opioid toxicity. Individual susceptibility to methadone may be determined by screening for CYP2B6*6.
Association of reading disability on chromosome 6p22 in the Afrikaner population.
Platko, Jill V; Wood, Frank B; Pelser, Izelda; Meyer, Marianne; Gericke, George S; O'Rourke, Julia; Birns, Julie; Purcell, Shaun; Pauls, David L
2008-10-05
The genetic basis of reading disability (RD) has long been established through family and twin studies. More recently genetic linkage studies have identified genomic regions that appear to harbor susceptibility genes for RD. Association studies have been shown to have greater power for detecting genes of modest effect, particularly in genetically isolated populations. Hence, a case control study of RD was undertaken in the Afrikaner population in South Africa. Sixty-eight microsatellite markers in regions where linkages had been reported in previous studies were genotyped on 122 children with reading disability and 112 typically reading controls drawn from the same school population. A single allele of marker D6S299 showed a highly significant association with the RD phenotype (D6S299[229], P-value 0.000014). Other markers on other chromosomes also showed suggestive associations. Of particular interest were markers on chromosomes 1 and 15. These two regions have been implicated in studies of populations that formed the founding population in the Afrikaner population.
Daerga, Laila; Sjölander, Per; Jacobsson, Lars; Edin-Liljegren, Anette
2012-08-01
To investigate the confidence in primary health care, psychiatry and social services among the reindeer-herding Sami and the non-Sami population of northern Sweden. A semi-randomized, cross-sectional study design comprising 325 reindeer-herding Sami (171 men, 154 women) and a control population of 1,437 non-Sami (684 men, 753 women). A questionnaire on the confidence in primary health care, psychiatry, social services, and work colleagues was distributed to members of reindeer-herding families through the Sami communities and to the control population through the post. The relative risk for poor confidence was analyzed by calculating odds ratios with 95% confidence intervals adjusted for age and level of education. The confidence in primary health care and psychiatry was significantly lower among the reindeer-herding Sami compared with the control group. No differences were found between men and women in the reindeer-herding Sami population. In both the reindeer-herding Sami and the control population, younger people (≤ 48 years) reported significantly lower confidence in primary health care than older individuals (>48 years). A conceivable reason for the poor confidence in health care organizations reported by the reindeer-herding Sami is that they experience health care staff as poorly informed about reindeer husbandry and Sami culture, resulting in unsuitable or unrealistic treatment suggestions. The findings suggest that the poor confidence constitutes a significant obstacle of the reindeer-herding Sami to fully benefit from public health care services.
Patient Navigation by Community Health Workers Increases Access to Surgical Care in Rural Haiti.
Matousek, Alexi C; Addington, Stephen R; Kahan, Joseph; Sannon, Herriot; Luckner, Thelius; Exe, Chauvet; Jean Louis, Rodolphe R Eisenhower; Lipsitz, Stuart; Meara, John G; Riviello, Robert
2017-12-01
In the Hôpital Albert Schweitzer district in rural Haiti, patients from mountain areas receive fewer operations per capita than patients from the plains. Possible additional barriers for mountain patients include lower socioeconomic status, lack of awareness of financial support, illiteracy and unfamiliarity with the hospital system. We sought to increase the rate of elective surgery for a mountain population using a patient navigation program. Patient navigators were trained to guide subjects from a mountain population through the entire hospital process for elective surgery. We compared the rate of elective operations before and after the patient navigation intervention between three groups: a control group from a mountainous area, a control group from the plains and an intervention group from a mountainous area. The baseline elective operation rate differed significantly between the plains control group, the mountain control group and the mountain intervention group (361 vs. 57 vs. 68 operations per 100,000 population per year). The rate of elective surgery between the two mountain groups was not statistically different prior to the intervention. After the intervention, the elective operation rate in the mountain group that received patient navigation increased from 68 to 131 operations per 100,000 population per year (p = 0.017). Patient navigation doubled the elective operation rate for a mountain population in rural Haiti. While additional barriers to access remain for this vulnerable population, patient navigation is an essential augmentation to financial assistance programs to ensure that the poor gain access to surgical care.
Juhász, Anna; Palotás, András; Janka, Zoltán; Rimanóczy, Agnes; Palotás, Miklós; Bódi, Nikoletta; Boda, Krisztina; Zana, Marianna; Vincze, Gábor; Kálmán, János
2005-05-01
Apolipoprotein E gene (Apo(epsilon)) has three common alleles (epsilon2, epsilon3, and epsilon4), of which epsilon4 has been shown to be associated with an increased risk for Alzheimer's disease (AD). Possible additional genetic factors, like the -491A variant of ApoE promoter may modify the development of AD, independently of the ApoE allele status. The objective of this study was to investigate whether A/T allelic polymorphism at site-491 of the ApoE promoter is associated with AD in a Hungarian population. The genomic DNA isolated from peripheral blood lymphocytes of 52 late-onset AD and 53 control individuals was used as a template for the two examined polymorphisms and PCR assay was applied. The epsilon4 allele was significantly over-represented in the AD group (28%) as compared with the control population (7%). No significant differences have been found between the control and the AD populations regarding the occurrence of the promoter A allele frequencies (control: 77%, AD: 70%). However, the AA genotype was more frequent in the AD group (48%) than in the control (10%) when the presence of epsilon4 allele was also considered. It is unlikely therefore that the -491A variant of the ApoE promoter gene is an independent risk factor in the Hungarian AD population, but a linkage disequilibrium exists between the two examined mutations.
Kawaguchi, Akira
2014-09-17
A nonpathogenic strain of Rhizobium (=Agrobacterium) vitis, ARK-1, limited the development of grapevine crown gall. A co-inoculation with ARK-1 and the tumorigenic strain VAT07-1 at a 1:1 cell ratio resulted in a higher population of ARK-1 than VAT07-1 in shoots without tumors, but a significantly lower population of ARK-1 than VAT07-1 in grapevine shoots with tumors. ARK-1 began to significantly suppress the VAT07-1 population 2 d after the inoculation. This result indicated that ARK-1 reduced the pathogen population at the wound site through biological control. Although ARK-1 produced a zone of inhibition against other tumorigenic Rhizobium spp. in in vitro assays, antibiosis depended on the culture medium. ARK-1 did not inhibit the growth of tumorigenic R. radiobacter strain AtC1 in the antibiosis assay, but suppressed the AtC1-induced formation of tumors on grapevine shoots, suggesting that antibiosis by ARK-1 may not be the main mechanism responsible for biological control.
Tests for a disease-susceptibility locus allowing for an inbreeding coefficient (F).
Song, Kijoung; Elston, Robert C
2003-11-01
We begin by discussing the false positive test results that arise because of cryptic relatedness and population substructure when testing a disease susceptibility locus. We extend and evaluate the Hardy-Weinberg disequilibrium (HWD) method, allowing for an inbreeding coefficient (F) in a similar way that Devlin and Roeder (1999) allowed for inbreeding in a case-control study. Then we compare the HWD measure and the common direct measure of linkage disequilibrium, both when there is no population substructure (F = 0) and when there is population substructure (F not = 0), for a single marker. The HWD test statistic gives rise to false positives caused by population stratification. These false positives can be controlled by adjusting the test statistic for the amount of variance inflation caused by the inbreeding coefficient (F). The power loss for the HWD test that arises when controlling for population structure is much less than that which arises for the common direct measure of linkage disequilibrium. However, in the multiplicative model, the HWD test has virtually no power even when allowing for non-zero F.
Genetic Classification of Populations Using Supervised Learning
Bridges, Michael; Heron, Elizabeth A.; O'Dushlaine, Colm; Segurado, Ricardo; Morris, Derek; Corvin, Aiden; Gill, Michael; Pinto, Carlos
2011-01-01
There are many instances in genetics in which we wish to determine whether two candidate populations are distinguishable on the basis of their genetic structure. Examples include populations which are geographically separated, case–control studies and quality control (when participants in a study have been genotyped at different laboratories). This latter application is of particular importance in the era of large scale genome wide association studies, when collections of individuals genotyped at different locations are being merged to provide increased power. The traditional method for detecting structure within a population is some form of exploratory technique such as principal components analysis. Such methods, which do not utilise our prior knowledge of the membership of the candidate populations. are termed unsupervised. Supervised methods, on the other hand are able to utilise this prior knowledge when it is available. In this paper we demonstrate that in such cases modern supervised approaches are a more appropriate tool for detecting genetic differences between populations. We apply two such methods, (neural networks and support vector machines) to the classification of three populations (two from Scotland and one from Bulgaria). The sensitivity exhibited by both these methods is considerably higher than that attained by principal components analysis and in fact comfortably exceeds a recently conjectured theoretical limit on the sensitivity of unsupervised methods. In particular, our methods can distinguish between the two Scottish populations, where principal components analysis cannot. We suggest, on the basis of our results that a supervised learning approach should be the method of choice when classifying individuals into pre-defined populations, particularly in quality control for large scale genome wide association studies. PMID:21589856
Investigation of blood lead concentrations in dogs living in Flint, Michigan.
Langlois, Daniel K; Kaneene, John B; Yuzbasiyan-Gurkan, Vilma; Daniels, Barbara L; Mejia-Abreu, Hilda; Frank, Nancy A; Buchweitz, John P
2017-10-15
OBJECTIVE To measure blood lead concentrations (BLCs) in dogs living in Flint, Mich, following a declared water crisis and to assess potential associations of BLCs with demographic data, water sources, and clinical signs in these dogs. DESIGN Cross-sectional study. ANIMALS 284 dogs residing in Flint, Mich (test population), and 47 dogs residing in East Lansing, Mich (control population), and immediately adjacent areas. PROCEDURES Blood samples were collected at free screening clinics in Flint (test population) and at the Michigan State University College of Veterinary Medicine Veterinary Medical Center (control population). Owners of test population dogs completed questionnaires providing demographic and clinical information. Hematologic evaluations were performed; BLCs were measured by inductively coupled plasma-mass spectrometry. RESULTS 4 of 284 test population dogs had BLCs > 50 ppb; an additional 20 had BLCs > 20 ppb. Overall, BLCs of test population dogs were higher than those of control dogs. Within the test population, young dogs (≤ 2 years of age) had higher BLCs than old dogs (≥ 6 years of age). Only 7.2% of test population dogs were drinking unfiltered tap water at the time of screening; however, dogs that had been receiving filtered or bottled water for ≤ 3 months before screening had higher BLCs than did those that received such water for > 3 months. CONCLUSIONS AND CLINICAL RELEVANCE Taken together, findings suggested that the impact of the Flint water crisis extended to companion animals. Results highlighted the importance of maintaining awareness of lead exposure and considering both human and animal well-being in cases of environmental toxicant exposures.
Zhu, Qing; Fu, Zhenyan; Ma, Yitong; Yang, Hong; Huang, Ding; Xie, Xiang; Liu, Fen; Zheng, Yingying; Cha, Erdenbat
2013-08-01
Cytochrome P450 (CYP) 2J2 is expressed in the vascular endothelium and metabolizes arachidonic acid to biologically active epoxyeicosatrienoic acids (EETs). The EETs are potent endogenous vasodilators and inhibitors of vascular inflammation. The aim of the present study was to assess the association between the human CYP2J2 gene polymorphism and coronary artery disease (CAD) in a Han and Uygur population of China. We use two independent case-control studies: a Han population (206 CAD patients and 262 control subjects) and an Uygur population (336 CAD patients and 448 control subjects). All CAD patients and controls were genotyped for the same three single nucleotide polymorphisms (SNPs) (rs890293, rs11572223 and rs2280275) of CYP2J2 gene by a real-time PCR instrument. In the Uygur population, for total, the distribution of SNP3 (rs2280275) genotypes showed a significant difference between CAD and control participants (P=0.048). For total and men, the distribution of SNP3 (rs2280275) alleles and the dominant model (CC vs CT+TT) showed a significant difference between CAD and control participants (for allele: P=0.014 and P=0.035, respectively; for dominant model: P=0.014 and P=0.034, respectively). The significant difference in dominant model was retained after adjustment for covariates (OR: 0.279, 95% confidence interval [CI]: 0.176-0.440, P=0.001; OR: 0.240, 95% CI: 0.128-0.457, P=0.001, respectively). The CC genotype of rs2280275 in CYP2J2 gene could be a protective genetic marker of CAD and T allele may be a risk genetic marker of CAD in men of Uygur population in China. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.
Zhang, Qian; Yu, Lebao; Ge, Peicong; Ma, Yonggang; Zhang, Dong; Zhang, Yan; Wang, Rong; Wang, Shuo; Zhao, Yuanli; Cao, Yong; Liu, Xingju; Deng, Xiaofeng; Zhao, Jizong
2018-06-01
Intracranial major artery stenosis/occlusion (ICASO) is a common cause of ischemic stroke worldwide. A number of studies have assessed the association of the p.R4810K polymorphism in the ring finger protein 213 (RNF213) gene with ICASO, but the results have not been entirely consistent. We conducted a case-control study to estimate the association between the p.R4810K polymorphism and the risk of ICASO in a Chinese population. A total of 124 patients and 230 controls were enrolled. Moreover, a meta-analysis was performed to evaluate this association in the East Asian populations. In our case-control study, the frequencies of the G/A genotype of p.R4810K were significantly higher in the ICASO patients than in the control group (4.03% versus .43%, P = .021, respectively). Moreover, in the meta-analysis, we assessed 7 case-control studies that included 1239 patients and 1377 controls. The pooled odds ratios (ORs) indicated significant association between the p.R4810K polymorphism and the ICASO risk in the dominant model (OR = 9.37, 95% confidence interval: 4.61-19.02, P = .000), the heterozygote comparison (OR = 8.97, 95% CI: 4.41-18.25, P = .000), and the allele comparison (OR = 9.50, 95% confidence interval: 4.71-19.19, P = .000) in the East Asian populations. Subgroup analysis based on ethnicity revealed that the risks in the Japanese and the Korean populations were higher than that in the Chinese population. The p.R4810K polymorphism was associated with an increased risk of ICASO in the East Asian populations. Further studies on the function of the RNF213 protein and the clinical features of this subtype of ICASO are needed. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.
Bandera, Elisa V; Chandran, Urmila; Zirpoli, Gary; McCann, Susan E; Ciupak, Gregory; Ambrosone, Christine B
2013-05-31
Recruitment of controls remains a challenge in case-control studies and particularly in studies involving minority populations. We compared characteristics of controls recruited through random digit dialing (RDD) to those of community controls enrolled through churches, health events and other outreach sources among women of African ancestry (AA) participating in the Women's Circle of Health Study, a case-control study of breast cancer. Odds ratios and 95% confidence intervals were also computed using unconditional logistic regression to evaluate the impact of including the community controls for selected variables relevant to breast cancer and for which there were significant differences in distribution between the two control groups. Compared to community controls (n=347), RDD controls (n=207) had more years of education and higher income, lower body mass index, were more likely to have private insurance, and less likely to be single. While the percentage of nulliparous women in the two groups was similar, community controls tended to have more children, have their first child at a younger age, and were less likely to breastfeed their children. Dietary intake was similar in the two groups. Compared to census data, the combination of RDD and community controls seems to be more representative of the general population than RDD controls alone. Furthermore, the inclusion of the community group had little impact on the magnitude of risk estimates for most variables, while enhancing statistical power. Community-based recruitment was found to be an efficient and feasible method to recruit AA controls.
Singh, Karan; Kochar, Ekta; Prasad, N. G.
2015-01-01
Background Ability to resist temperature shock is an important component of fitness of insects and other ectotherms. Increased resistance to temperature shock is known to affect life-history traits. Temperature shock is also known to affect reproductive traits such as mating ability and viability of gametes. Therefore selection for increased temperature shock resistance can affect the evolution of reproductive traits. Methods We selected replicate populations of Drosophila melanogaster for resistance to cold shock. We then investigated the evolution of reproductive behavior along with other components of fitness- larval survivorship, adult mortality, fecundity, egg viability in these populations. Results We found that larval survivorship, adult mortality and fecundity post cold shock were not significantly different between selected and control populations. However, compared to the control populations, the selected populations laid significantly higher percentage of fertile eggs (egg viability) 24 hours post cold shock. The selected populations had higher mating frequency both with and without cold shock. After being subjected to cold shock, males from the selected populations successfully mated with significantly more non-virgin females and sired significantly more progeny compared to control males. Conclusions A number of studies have reported the evolution of survivorship in response to selection for temperature shock resistance. Our results clearly indicate that adaptation to cold shock can involve changes in components of reproductive fitness. Our results have important implications for our understanding of how reproductive behavior can evolve in response to thermal stress. PMID:26065704
Enhanced leaf nitrogen status stabilizes omnivore population density.
Liman, Anna-Sara; Dalin, Peter; Björkman, Christer
2017-01-01
Plant traits can mediate the strength of interactions between omnivorous predators and their prey through density effects and changes in the omnivores' trophic behavior. In this study, we explored the established assumption that enhanced nutrient status in host plants strengthens the buffering effect of plant feeding for omnivorous predators, i.e., prevents rapid negative population growth during prey density decline and thereby increases and stabilizes omnivore population density. We analyzed 13 years of field data on population densities of a heteropteran omnivore on Salix cinerea stands, arranged along a measured leaf nitrogen gradient and found a 195 % increase in omnivore population density and a 63 % decrease in population variability with an increase in leaf nitrogen status from 26 to 40 mgN × g -1 . We recreated the leaf nitrogen gradient in a greenhouse experiment and found, as expected, that increasing leaf nitrogen status enhanced omnivore performance but reduced per capita prey consumption. Feeding on high nitrogen status host plants can potentially decouple omnivore-prey population dynamics and allow omnivores to persist and function effectively at low prey densities to provide "background level" control of insect herbivores. This long-term effect is expected to outweigh the short-term effect on per capita prey consumption-resulting in a net increase in population predation rates with increasing leaf nitrogen status. Conservation biological control of insect pests that makes use of omnivore background control could, as a result, be manipulated via management of crop nitrogen status.
Qin, Pengfei; Li, Zhiqiang; Jin, Wenfei; Lu, Dongsheng; Lou, Haiyi; Shen, Jiawei; Jin, Li; Shi, Yongyong; Xu, Shuhua
2014-02-01
Population stratification acts as a confounding factor in genetic association studies and may lead to false-positive or false-negative results. Previous studies have analyzed the genetic substructures in Han Chinese population, the largest ethnic group in the world comprising ∼20% of the global human population. In this study, we examined 5540 Han Chinese individuals with about 1 million single-nucleotide polymorphisms (SNPs) and screened a panel of ancestry informative markers (AIMs) to facilitate the discerning and controlling of population structure in future association studies on Han Chinese. Based on genome-wide data, we first confirmed our previous observation of the north-south differentiation in Han Chinese population. Second, we developed a panel of 150 validated SNP AIMs to determine the northern or southern origin of each Han Chinese individual. We further evaluated the performance of our AIMs panel in association studies in simulation analysis. Our results showed that this AIMs panel had sufficient power to discern and control population stratification in Han Chinese, which could significantly reduce false-positive rates in both genome-wide association studies (GWAS) and candidate gene association studies (CGAS). We suggest this AIMs panel be genotyped and used to control and correct population stratification in the study design or data analysis of future association studies, especially in CGAS which is the most popular approach to validate previous reports on genetic associations of diseases in post-GWAS era.
Roda, Amy; Nachman, Gösta; Weihman, Scott; Yong Cong, Mary; Zimmerman, Fredrick
2016-01-01
Giant African snail (Achatina fulica (Bowdich, 1822)), an important invasive snail, was recently found in South Florida, USA. An extensive eradication effort was initiated consisting of pesticide applications, debris removal and hand collections. We studied the reproduction capacity and population dynamics of snails collected from 22 populations for two years to help evaluate the likely success of the eradication program. A total of 23,890 snails, ranging from 25-131 mm, were measured, dissected and the number of eggs in each snail counted. Gravid snails ranged from 48-128 mm. Only 5% of snails had eggs, which were found year round. As the snails increased in size, they were more likely to include reproducing individuals. However, the percentage of gravid snails peaked when snails were approximately 90 mm. Although more prevalent, small (<65 mm) adults contributed fewer eggs to the population than the larger snails. We evaluated the effect of control measures on six populations having >1000 adult snails and used data from the two largest populations to investigate how environmental factors (temperature, humidity, and rainfall) interacted with population dynamics and control measures. More snails were collected in weeks with high humidity and more gravid snails were collected when the temperature was higher. The addition of metaldehyde pesticides had the greatest impact on population dynamics by reducing snail numbers. In populations with fewer snails, their numbers were already declining before the use of metaldehyde, although the new treatment accelerated the process. As a consequence of the eradication program, egg-producing snails were no longer collected from most populations by the end of the study. The aggressive and persistent control efforts apparently lead to reduced populations of egg producing snails, eventually resulting in local extinctions of this important pest.
2016-01-01
Giant African snail (Achatina fulica (Bowdich, 1822)), an important invasive snail, was recently found in South Florida, USA. An extensive eradication effort was initiated consisting of pesticide applications, debris removal and hand collections. We studied the reproduction capacity and population dynamics of snails collected from 22 populations for two years to help evaluate the likely success of the eradication program. A total of 23,890 snails, ranging from 25–131 mm, were measured, dissected and the number of eggs in each snail counted. Gravid snails ranged from 48–128 mm. Only 5% of snails had eggs, which were found year round. As the snails increased in size, they were more likely to include reproducing individuals. However, the percentage of gravid snails peaked when snails were approximately 90 mm. Although more prevalent, small (<65 mm) adults contributed fewer eggs to the population than the larger snails. We evaluated the effect of control measures on six populations having >1000 adult snails and used data from the two largest populations to investigate how environmental factors (temperature, humidity, and rainfall) interacted with population dynamics and control measures. More snails were collected in weeks with high humidity and more gravid snails were collected when the temperature was higher. The addition of metaldehyde pesticides had the greatest impact on population dynamics by reducing snail numbers. In populations with fewer snails, their numbers were already declining before the use of metaldehyde, although the new treatment accelerated the process. As a consequence of the eradication program, egg-producing snails were no longer collected from most populations by the end of the study. The aggressive and persistent control efforts apparently lead to reduced populations of egg producing snails, eventually resulting in local extinctions of this important pest. PMID:27861504
Tanash, Hanan A; Ekström, Magnus; Rönmark, Eva; Lindberg, Anne; Piitulainen, Eeva
2017-09-01
Knowledge about the natural history of severe alpha 1-antitrypsin (AAT) deficiency (PiZZ) is limited. Our aim was to compare the survival of PiZZ individuals with randomly selected controls from the Swedish general population.The PiZZ subjects (n=1585) were selected from the Swedish National AATD Register. The controls (n=5999) were randomly selected from the Swedish population register. Smoking habits were known for all subjects.Median follow-up times for the PiZZ subjects (731 never-smokers) and controls (3179 never-smokers) were 12 and 17 years, respectively (p<0.001). During follow-up, 473 PiZZ subjects (30%), and 747 controls (12%) died. The PiZZ subjects had a significantly shorter survival time than the controls, p<0.001. After adjustment for gender, age, smoking habits and presence of respiratory symptoms, the risk of death was still significantly higher for the PiZZ individuals than for the controls, hazard ratio (HR) 3.2 (95% CI 2.8-3.6; p<0.001). By contrast, the risk of death was not increased in never-smoking PiZZ individuals identified by screening, compared to never-smoking controls, HR 1.2 (95% CI 0.6-2.2).The never-smoking PiZZ individuals identified by screening had a similar life expectancy to the never-smokers in the Swedish general population. Early diagnosis of AAT deficiency is of utmost importance. Copyright ©ERS 2017.
A case-control study: occupational cooking and the risk of uveal melanoma
2010-01-01
Background A European-wide population based case-control study (European rare cancer study) undertaken in nine European countries examined risk factors for uveal melanoma. They found a positive association between cooks and the risk of uveal melanoma. In our study we examine whether cooks or people who worked in cook related jobs have an increased uveal melanoma risk. Methods We conducted a case-control study during 2002 and 2005. Overall, 1653 eligible subjects (age range: 20-74 years, living in Germany) participated. Interviews were conducted with 459 incident uveal melanoma cases, 827 population controls, 180 ophthalmologist controls and 187 sibling controls. Data on occupational exposure were obtained from a self-administered postal questionnaire and a computer-assisted telephone interview. We used conditional logistic regression to estimate odds ratios adjusting for the matching factors. Results Overall, we did not observe an increased risk of uveal melanoma among people who worked as cooks or who worked in cook related jobs. When we restricted the source population of our study to the population of the Federal State of Northrhine-Westphalia, we observed an increased risk among subjects who were categorized as cooks in the cases-control analysis. Conclusion Our results are in conflict with former results of the European rare cancer study. Considering the rarity of the disease laboratory in vitro studies of human uveal melanoma cell lines should be done to analyze potential exposure risk factors like radiation from microwaves, strong light from incandescent ovens, or infrared radiation. PMID:20969762
Uniqueness of polymorphism for a discrete, selection-migration model with genetic dominance
James F. Selgrade; James H. Roberds
2009-01-01
The migration into a natural population of a controlled population, e.g., a transgenic population, is studied using a one island selection-migration model. A 2-dimensional system of nonlinear difference equations describes changes in allele frequency and population size between generations. Biologically reasonable conditions are obtained which guarantee the existence...
Soviet Marxism and population policy.
Vonfrank, A
1984-01-01
American demographers have maintained that Marxism, notably Soviet Marxism, is consistently pronatalist. The Soviet view is said to be that population growth is not a problem and that birth control policies in either developed or developing societies are to be rejected; the "correct" (i.e., socialist) socioeconomic structure is the true solution to alleged population problems. Such representations of Soviet thought greatly oversimplify the Soviet position as well as fail to discern the changes in Soviet thought that have been occurring. Since the 1960s Soviet writers have increasingly acknowledged that population growth is, to a considerable degree, independent of the economic base of society and that conscious population policies may be needed to either increase or decrease the rate of population growth. Even socialist societies can have population problems. And where population growth is too rapid, as in the developing countries, policies to slow such growth are needed because of the threat to economic development. However, the Soviets continue to stress that birth control policies must go hand-in-hand with social and economic development policies if they are to be effective.
The “Dry-Run” Analysis: A Method for Evaluating Risk Scores for Confounding Control
Wyss, Richard; Hansen, Ben B.; Ellis, Alan R.; Gagne, Joshua J.; Desai, Rishi J.; Glynn, Robert J.; Stürmer, Til
2017-01-01
Abstract A propensity score (PS) model's ability to control confounding can be assessed by evaluating covariate balance across exposure groups after PS adjustment. The optimal strategy for evaluating a disease risk score (DRS) model's ability to control confounding is less clear. DRS models cannot be evaluated through balance checks within the full population, and they are usually assessed through prediction diagnostics and goodness-of-fit tests. A proposed alternative is the “dry-run” analysis, which divides the unexposed population into “pseudo-exposed” and “pseudo-unexposed” groups so that differences on observed covariates resemble differences between the actual exposed and unexposed populations. With no exposure effect separating the pseudo-exposed and pseudo-unexposed groups, a DRS model is evaluated by its ability to retrieve an unconfounded null estimate after adjustment in this pseudo-population. We used simulations and an empirical example to compare traditional DRS performance metrics with the dry-run validation. In simulations, the dry run often improved assessment of confounding control, compared with the C statistic and goodness-of-fit tests. In the empirical example, PS and DRS matching gave similar results and showed good performance in terms of covariate balance (PS matching) and controlling confounding in the dry-run analysis (DRS matching). The dry-run analysis may prove useful in evaluating confounding control through DRS models. PMID:28338910
Diagnostic performance of a commercial immunoblot assay for myositis antibody testing.
Bundell, Chris; Rojana-Udomsart, Arada; Mastaglia, Frank; Hollingsworth, Peter; McLean-Tooke, Andrew
2016-06-01
The objective of this study was to establish a population based reference range for a commercial immunoblot assay detecting myositis specific autoantibodies (MSAs) and myositis associated autoantibodies (MAAs), and to assess the diagnostic performance of this reference range against the manufacturer's recommended ranges in a myositis patient cohort. A total of 124 patients from a myositis cohort and 197 healthy controls were serologically assessed using a commercial immunoblot containing eleven autoantigens (Jo-1, EJ, OJ, PL7, PL12, Mi-2, SRP, Ku, PMScl75, PMScl100 and Ro52) according to the manufacturer's instructions. Use of the manufacturer's reference ranges resulted in detection of MSAs in 19.4% of myositis patients and 9.1% of controls; MAAs were detected in 41.1% of myositis patients and 14.2% of controls. Reference values derived from the healthy control population resulted in significant differences in cut-off values for some autoantibodies, particularly Ro52 and PMScl75. Use of local reference ranges reduced detection of MSAs to 16.9% of myositis patients and 3% of healthy controls, with MAAs 23.4% of patients and 2% of healthy controls. Application of population based reference ranges resulted in significant differences in detection of MSAs and MAAs compared to the manufacturer's recommended ranges. Cut-off levels should be assessed to ensure suitability for the population tested. Copyright © 2016. Published by Elsevier B.V.
Integrated pest management and allocation of control efforts for vector-borne diseases
Ginsberg, H.S.
2001-01-01
Applications of various control methods were evaluated to determine how to integrate methods so as to minimize the number of human cases of vector-borne diseases. These diseases can be controlled by lowering the number of vector-human contacts (e.g., by pesticide applications or use of repellents), or by lowering the proportion of vectors infected with pathogens (e.g., by lowering or vaccinating reservoir host populations). Control methods should be combined in such a way as to most efficiently lower the probability of human encounter with an infected vector. Simulations using a simple probabilistic model of pathogen transmission suggest that the most efficient way to integrate different control methods is to combine methods that have the same effect (e.g., combine treatments that lower the vector population; or combine treatments that lower pathogen prevalence in vectors). Combining techniques that have different effects (e.g., a technique that lowers vector populations with a technique that lowers pathogen prevalence in vectors) will be less efficient than combining two techniques that both lower vector populations or combining two techniques that both lower pathogen prevalence, costs being the same. Costs of alternative control methods generally differ, so the efficiency of various combinations at lowering human contact with infected vectors should be estimated at available funding levels. Data should be collected from initial trials to improve the effects of subsequent interventions on the number of human cases.
Computer simulation of vasectomy for wolf control
Haight, R.G.; Mech, L.D.
1997-01-01
Recovering gray wolf (Canis lupus) populations in the Lake Superior region of the United States are prompting state management agencies to consider strategies to control population growth. In addition to wolf removal, vasectomy has been proposed. To predict the population effects of different sterilization and removal strategies, we developed a simulation model of wolf dynamics using simple rules for demography and dispersal. Simulations suggested that the effects of vasectomy and removal in a disjunct population depend largely on the degree of annual immigration. With low immigration, periodic sterilization reduced pup production and resulted in lower rates of territory recolonization. Consequently, average pack size, number of packs, and population size were significantly less than those for an untreated population. Periodically removing a proportion of the population produced roughly the same trends as did sterilization; however, more than twice as many wolves had to be removed than sterilized. With high immigration, periodic sterilization reduced pup production but not territory recolonization and produced only moderate reductions in population size relative to an untreated population. Similar reductions in population size were obtained by periodically removing large numbers of wolves. Our analysis does not address the possible effects of vasectomy on larger wolf populations, but it suggests that the subject should be considered through modeling or field testing.
Lasram, Khaled; Ben Halim, Nizar; Hsouna, Sana; Kefi, Rym; Arfa, Imen; Ghazouani, Welid; Jamoussi, Henda; Benrahma, Houda; Kharrat, Najla; Rebai, Ahmed; Ben Ammar, Slim; Bahri, Sonia; Barakat, Abdelhamid; Abid, Abdelmajid; Abdelhak, Sonia
2014-01-01
Aims. Genetic association studies have reported the E23K variant of KCNJ11 gene to be associated with Type 2 diabetes. In Arab populations, only four studies have investigated the role of this variant. We aimed to replicate and validate the association between the E23K variant and Type 2 diabetes in Tunisian and Arab populations. Methods. We have performed a case-control association study including 250 Tunisian patients with Type 2 diabetes and 267 controls. Allelic association has also been evaluated by 2 meta-analyses including all population-based studies among Tunisians and Arabs (2 and 5 populations, resp.). Results. A significant association between the E23K variant and Type 2 diabetes was found (OR = 1.6, 95% CI = 1.14–2.27, and P = 0.007). Furthermore, our meta-analysis has confirmed the significant role of the E23K variant in susceptibility of Type 2 diabetes in Tunisian and Arab populations (OR = 1.29, 95% CI = 1.15–1.46, and P < 10−3 and OR = 1.33, 95% CI = 1.13–1.56, and P = 0.001, resp.). Conclusion. Both case-control and meta-analyses results revealed the significant association between the E23K variant of KCNJ11 and Type 2 diabetes among Tunisians and Arabs. PMID:25165692
Conceptions of Contraceptive Use in Rural KwaZulu-Natal, South Africa: Lessons for Programming
Ndinda, Catherine; Ndhlovu, Tidings; Khalema, Nene Ernest
2017-01-01
Community family planning programmes in South Africa arose from the controversial apartheid history of controlling the African population while encouraging the growth of European migrant population. Post-apartheid population policies shifted away from population control to aligning policies to the global agenda that placed emphasis on the link between population and development. The focus on population and development polices in post-apartheid South Africa is on social equality, justice and peace rather than controlling sections of the population. Given the shift, this paper interrogates the conceptions of contraceptive use among rural communities in KwaZulu-Natal. Our primary objective is to understand the dynamics surrounding access to and use of family planning services in peri-urban and rural areas of KwaZulu-Natal. Using focus group data, the findings of the study suggest that different social categories interact with the family planning programmes differently. How teenagers and married women perceive the value of family planning differs. Gender differences regarding the use of condoms are also evident. The paper attempts to grapple with the non-use of condoms despite the knowledge that these prevent pregnancy and provide protection from sexually-transmitted diseases. The contribution of this paper lies in its identification of socio-cultural factors and the political economy underlying the different attitudes towards contraceptive use in rural KwaZulu-Natal. PMID:28350334
Conceptions of Contraceptive Use in Rural KwaZulu-Natal, South Africa: Lessons for Programming.
Ndinda, Catherine; Ndhlovu, Tidings; Khalema, Nene Ernest
2017-03-28
Community family planning programmes in South Africa arose from the controversial apartheid history of controlling the African population while encouraging the growth of European migrant population. Post-apartheid population policies shifted away from population control to aligning policies to the global agenda that placed emphasis on the link between population and development. The focus on population and development polices in post-apartheid South Africa is on social equality, justice and peace rather than controlling sections of the population. Given the shift, this paper interrogates the conceptions of contraceptive use among rural communities in KwaZulu-Natal. Our primary objective is to understand the dynamics surrounding access to and use of family planning services in peri-urban and rural areas of KwaZulu-Natal. Using focus group data, the findings of the study suggest that different social categories interact with the family planning programmes differently. How teenagers and married women perceive the value of family planning differs. Gender differences regarding the use of condoms are also evident. The paper attempts to grapple with the non-use of condoms despite the knowledge that these prevent pregnancy and provide protection from sexually-transmitted diseases. The contribution of this paper lies in its identification of socio-cultural factors and the political economy underlying the different attitudes towards contraceptive use in rural KwaZulu-Natal.
Yao, Yao; Wen, Yueqiang; Du, Tingfu; Sun, Ning; Deng, Hong; Ryan, Joanne; Rao, Shuquan
2016-03-15
Major depressive disorder (MDD) is one of the most prevalent psychiatric illnesses with heritability of up to 38%. The fat mass- and obesity-associated (FTO) gene, in particular the single nucleotide polymorphism (SNP) rs9939609, has been identified as a genetic risk loci associated with MDD. However, most prior studies have involved European and American populations. Whether rs9939609 is an true risk SNP for MDD in Asian populations remains inconclusive. In the present study, we conducted a meta-analysis of the association between rs9939609 and MDD in Asian populations by combining 5 available case-control samples totaling 6531 cases and 12,359 controls. Our meta-analysis suggests that rs9939609 is not a risk SNP for MDD in Asian populations by fixed effect model (Z=1.04, P=0.30, OR=0.96, 95% CI=0.90-1.03). The age distribution and gender ratios were not matched well in the combined samples of cases and controls. Publication bias might be also considered with only a relatively small number of association studies of FTO rs9939609 with MDD in Asian populations. The absence of association of rs9939609 with MDD in our Asian populations suggests a potential genetic heterogeneity in the susceptibility of MDD on this locus. Copyright © 2015 Elsevier B.V. All rights reserved.
Howell, Anna D; Daugovish, Oleg
2013-02-01
The spider mite, Eotetranychus lewisi (McGregor) (Acari: Tetranychidae), is a new emerging pest in California commercial strawberries. The predatory mite Phytoseiulus persimilis (Athias-Henriot) (Acari: Phytoseiidae), typically used for biocontrol of Tetranychus urticae (Koch) (Acari: Tetranychidae), provided growers little to no control of E. lewisi. Four commonly used phytoseiid predatory mites: P. persimilis, Neoseiulus californicus (McGregor), N. fallacis (Garman), and Amblyseius andersoni (Chant), were used in lab studies to investigate which is best at managing E. lewisi populations. We als o investigated t he interactions between T. urticae and E. lewisi and in relation to phytoseiid efficiency given the potential for indirect effects of biocontrol. When E. lewisi and T. urticae are present on the same leaf, T. urticae populations increase and begin displacing E. lewisi. P. persimilis did not feed on E. lewisi, but the other three predatory mites consumed the spider mites and lowered their populations. When both E. lewisi and T. urticae are present on the same leaf, N. fallacis and A. andersoni fed on both types of mites equally and were capable of decreasing both populations. N. californicus fed on E. lewisi first and decreased its population, but allowed T. urticae populations to increase. P. persimilis may be insufficient at controlling E. lewisi and its use may instead enhance E. lewisi populations.
China's one-child family: a famine-forced decision.
1985-01-01
The Reagan administration refuses to recognize the achievements of China's population program and the practical and humanitarian considerations which lead to China's adoption of vigorous family planning policies. China began to express concern about population growth in 1960, and this concern was, in part, prompted by a severe famine. The occurence of the famine was only recently brought to the attention of the rest of the world when demographers uncovered statistical evidence indicating that as many as 30 million Chinese may have perished in the 1958-62 famine. The famine was due both to faulty agricultural policies and to severe crop damage in 1959 and 1960. The family planning program initiated in 1960 was interrupted by the cultural revolution, and the effort to control population growth was not reinstituted until the early 1970s. By 1979 childbearing among the postwar baby boom generation boosted population growth rates to a new high, and the government began advocating a 1-child family. The national census of 1982 revealed that China's population doubled between 1949-1982 and in 1982 exceeded 1 billion. Severe famine and economic chaos were forecasted for the near future if population growth was not severely and immediately curbed. The government responded to this impending threat by instituting stringent measures to restrict 2nd order births. Abortion was permitted for cases of contraceptive failure; however, the government warned that severe penalties would be imposed on anyone who tried to ensure that their 1 child was a son by practicing female infanticide, a traditional but illegal practice. The government admits that some couples, under extreme pressure from local officials, resorted to infanticide. The Reagan administration used the infanticide issue to descredit the Chinese population program, and recently announced its intention to withhold US$10 million in previously approved funding from the UN Fund for Population Activities because the agency provided support for China's coercive population program. The administration also voiced its distorted preceion of China's program at the 1984 International Conference on Population. James Buckley, the administration's delegate to the conference, blamed state controlled economies for interfering with natural mechanisms for slowing population growth. In reality, China's progress in controlling population growth accounts for almost all of the 20% reduction in the world's population growth rate, since the late 1960s. By slowing the world's population growth rate, China contributed not only to it own economic well-being but to the economic well-being of all nations including the US. Yet Reagan condemns rather than praises China for enduring the hardship of controlling its fertility.
Insulation workers in Belfast. 1. Comparison of a random sample with a control population1
Wallace, William F. M.; Langlands, Jean H. M.
1971-01-01
Wallace, W. F. M., and Langlands, J. H. M. (1971).Brit. J. industr. Med.,28, 211-216. Insulation workers in Belfast. 1. Comparison of a random sample with a control population. A sample of 50 men was chosen at random from the population of asbestos insulators in Belfast and matched with a control series of men of similar occupational group with respect to age, height, and smoking habit. Significantly more of the insulators complained of cough and sputum and had basal rales on examination. Clubbing was assessed by means of measurements of the hyponychial angle of both index fingers. These angles were significantly greater in the group of insulators. Twenty-one insulators had ϰ-rays which showed pleural calcification with or without pulmonary fibrosis; one control ϰ-ray showed pulmonary fibrosis. The insulators had no evidence of airways obstruction but static lung volume was reduced and their arterial oxygen tension was lower than that of the controls and their alveolar-arterial oxygen gradient was greater. PMID:5557841
Estimating risk and rate levels, ratios and differences in case-control studies.
King, Gary; Zeng, Langche
2002-05-30
Classic (or 'cumulative') case-control sampling designs do not admit inferences about quantities of interest other than risk ratios, and then only by making the rare events assumption. Probabilities, risk differences and other quantities cannot be computed without knowledge of the population incidence fraction. Similarly, density (or 'risk set') case-control sampling designs do not allow inferences about quantities other than the rate ratio. Rates, rate differences, cumulative rates, risks, and other quantities cannot be estimated unless auxiliary information about the underlying cohort such as the number of controls in each full risk set is available. Most scholars who have considered the issue recommend reporting more than just risk and rate ratios, but auxiliary population information needed to do this is not usually available. We address this problem by developing methods that allow valid inferences about all relevant quantities of interest from either type of case-control study when completely ignorant of or only partially knowledgeable about relevant auxiliary population information.
Should we expect population thresholds for wildlife disease?
Lloyd-Smith, James O.; Cross, P.C.; Briggs, C.J.; Daugherty, M.; Getz, W.M.; Latto, J.; Sanchez, M.; Smith, A.; Swei, A.
2005-01-01
Host population thresholds for invasion or persistence of infectious disease are core concepts of disease ecology, and underlie on-going and controversial disease control policies based on culling and vaccination. Empirical evidence for these thresholds in wildlife populations has been sparse, however, though recent studies have narrowed this gap. Here we review the theoretical bases for population thresholds for disease, revealing why they are difficult to measure and sometimes are not even expected, and identifying important facets of wildlife ecology left out of current theories. We discuss strengths and weaknesses of selected empirical studies that have reported disease thresholds for wildlife, identify recurring obstacles, and discuss implications of our imperfect understanding of wildlife thresholds for disease control policy.
Keeping the herds healthy and alert: Implications of predator control for infectious disease
Packer, Craig; Holt, Robert D.; Hudson, Peter J.; Lafferty, Kevin D.; Dobson, Andrew P.
2003-01-01
Predator control programmes are generally implemented in an attempt to increase prey population sizes. However, predator removal could prove harmful to prey populations that are regulated primarily by parasitic infections rather than by predation. We develop models for microparasitic and macroparasitic infection that specify the conditions where predator removal will (a) increase the incidence of parasitic infection, (b) reduce the number of healthy individuals in the prey population and (c) decrease the overall size of the prey population. In general, predator removal is more likely to be harmful when the parasite is highly virulent, macroparasites are highly aggregated in their prey, hosts are long-lived and the predators select infected prey.
Bader, E J; Truax, H
1991-01-01
The focus of the discussion of US national environmental efforts on population growth issues is on carrying capacity, the impact of the antiabortion movement, the insensitivity of some population control advocated to people of color, and congressional and presidential actions. Efforts are being made to surmount the mistrust that has characterized efforts to deal with population issues. The World Wildlife Fund, the Sierra Club, and the National Audubon Society recognize the need for population stabilization, albeit with meager budgets. Carrying capacity is the number of people the earth can sustain without rapidly depleting non-renewable resources or degrading resources necessary to sustain life. In 1970, Earth Day called for stabilization of the global population, but most celebrations of Earth Day in 1990 did not recognize this. Sensitive issues are involved, and the abortion controversy has muffled open forums on population growth. Lobbyists were successful in having the US withdraw funding for international family planning (FP) programs that had abortion components. Then Reagan eliminated all funding to the UN Fund for Population Activities, because of China's FP policies. The results for women have been disastrous. Zero Population Growth has been conducting information meetings for environmental groups. The National wildlife Federation has a new program linking population and environmental issues but will not deal with the issue of abortion. A Philadelphia editorial recommended implanted contraceptives for welfare mothers, which raised fears of the reemergence of the eugenic movement which sought involuntary sterilization or population control for the poor. Another effort was to protect the US from immigration as a way of curbing population growth. Meaningful change means education women, changing unfavorable survival conditions, and heeding the reasons women have children. Japan's FP Association criticizes population control efforts undertaken for economic and political benefit without attention being paid to people's lives. An informal coalition is supporting a large FP grant to the USAID. Senate leadership is more open for FP issues, and a bill has been proposed to increase international FP funds.
Mazloum, Marie; Bailey, Helen D; Heiden, Tamika; Armstrong, Bruce K; de Klerk, Nicholas; Milne, Elizabeth
2012-05-01
An Australian study of childhood leukaemia (Aus-ALL) previously reported that control participation was positively associated with socio-economic status (SES). A similar study of childhood brain tumours (Aus-CBT) was carried out 4 years later, and this paper compares control participation and its relationship with SES in the two studies. To assess the representativeness of controls in terms of SES, the addresses of controls were linked to Australian Bureau of Statistics Census 2006 Collection Districts (CDs), and hence to area-based indices of SES. Independent sample t-tests and chi-squared tests were used to compare the SES indices of CDs where Aus-CBT controls lived with those where Aus-ALL controls lived and with those of all CDs where Australian families lived. The overall percentage of eligible families who agreed to participate was lower in Aus-CBT (53.9%) than in Aus-ALL (70.3%). Control families in both studies were of higher SES than the general population, while the distribution of SES among recruited controls was similar in both studies. These findings provide some reassurance that the observed decline in research participation over time may not be associated with an increasingly unrepresentative participant population. © 2012 Blackwell Publishing Ltd.
Strategies to control a common carp population by pulsed commercial harvest
Colvin, Michael E.; Pierce, Clay; Stewart, Timothy W.; Grummer, Scott E.
2012-01-01
Commercial fisheries are commonly used to manage nuisance fishes in freshwater systems, but such efforts are often unsuccessful. Strategies for successfully controlling a nuisance population of common carp Cyprinus carpio by pulsed commercial harvest were evaluated with a combination of (1) field sampling, (2) population estimation and CPUE indexing, and (3) simulation using an exponential semidiscrete biomass dynamics model (SDBDM). The range of annual fishing mortalities (F) that resulted in successful control (F = 0.244–0.265) was narrow. Common carp biomass dynamics were sensitive to unintentional underharvest due to high rates of surplus production and a biomass doubling time of 2.7 years. Simulations indicated that biomanipulation never achieved successful control unless supplemental fishing mortality was imposed. Harvest of a majority of annual production was required to achieve successful control, as indicated by the ecotrophic coefficient (EC). Readily available biomass data and tools such as SDBDMs and ECs can be used in an adaptive management framework to successfully control common carp and other nuisance fishes by pulsed commercial fishing.
Gratitude mediates quality of life differences between fibromyalgia patients and healthy controls.
Toussaint, Loren; Sirois, Fuschia; Hirsch, Jameson; Weber, Annemarie; Vajda, Christian; Schelling, Jorg; Kohls, Niko; Offenbacher, Martin
2017-09-01
Despite a growing literature on the benefits of gratitude for adjustment to chronic illness, little is known about gratitude in medical populations compared to healthy populations, or the degree to which potential deficits in gratitude might impact quality of life. The purpose of the present study was to (1) examine levels of gratitude and quality of life in fibromyalgia patients and healthy controls and (2) consider the role of gratitude in explaining quality of life differences between fibromyalgia patients and healthy controls. Participants were 173 fibromyalgia patients and 81 healthy controls. All participants completed measures of gratitude, quality of life, and socio-demographics. Although gratitude was positively associated with quality of life, levels of gratitude and quality of life were lower in the fibromyalgia sample relative to the healthy controls. This difference in gratitude partially mediated differences in quality of life between the two groups after controlling for socio-demographic variables. Our findings suggest that gratitude is a valuable positive psychological trait for quality of life in people with fibromyalgia. Interventions to improve gratitude in this patient population may also bring enhancement in quality of life.
Dos Reis, Célia A; Florentino, Helenice de O; Cólon, Diego; Rosa, Suélia R Fleury; Cantane, Daniela R
2018-05-01
Dengue fever, chikungunya and zika are caused by different viruses and mainly transmitted by Aedes aegypti mosquitoes. These diseases have received special attention of public health officials due to the large number of infected people in tropical and subtropical countries and the possible sequels that those diseases can cause. In severe cases, the infection can have devastating effects, affecting the central nervous system, muscles, brain and respiratory system, often resulting in death. Vaccines against these diseases are still under development and, therefore, current studies are focused on the treatment of diseases and vector (mosquito) control. This work focuses on this last topic, and presents the analysis of a mathematical model describing the population dynamics of Aedes aegypti, as well as present the design of a control law for the mosquito population (vector control) via exact linearization techniques and optimal control. This control strategy optimizes the use of resources for vector control, and focuses on the aquatic stage of the mosquito life. Theoretical and computational results are also presented. Copyright © 2017 Elsevier Inc. All rights reserved.
The Impact of Musical Training on Hand Biomechanics in String Musicians.
Gorniak, Stacey L; Collins, Evan D; Goldie Staines, Kimberly; Brooks, Forrest A; Young, Ricardo V
2018-04-01
The effects of musical training on the body in professional musicians remain an understudied area, particularly in reference to understanding and managing orthopedic/neuromuscular deviations and injuries in this population. The purpose of this study was to evaluate hand/finger fine motor function in musicians via physical examination as well as laboratory-based evaluations. Thirteen healthy noninjured young elite string musicians participated in this study. Performance of musicians was compared with healthy age-matched, sex-matched, and handedness-matched nonmusician controls. Musicians exhibited decreased intrinsic muscle strength compared with controls; however, no change in extrinsic muscle strength was found between groups. No between-group differences in overall force control were found; however, Group × Hand (right vs left) interactions were found in force control. These data suggest that musicians are a unique population with respect to: (1) fine motor control of the hand; and (2) exhibit changes in differential hand use. This suggests cortical reorganization of string musicians, such that this population should be studied separately from typical healthy controls with respect to hand function.
Lopez-Larrea, Carlos; Blanco-Gelaz, Miguel Angel; Torre-Alonso, Juan Carlos; Armas, Jacome Bruges; Suarez-Alvarez, Beatriz; Pruneda, Laura; Couto, Ana Rita; Gonzalez, Segundo; Lopez-Vázquez, Antonio; Martinez-Borra, Jesus
2006-01-01
Killer cell immunoglobulin-like receptors (KIRs) and human leukocyte antigen (HLA) loci are both highly polymorphic, and some HLA class I molecules bind and trigger cell-surface receptors specified by KIR genes. We examined whether the combination of KIR3DS1/3DL1 genes in concert with HLA-B27 genotypes is associated with susceptibility to ankylosing spondylitis (AS). Two HLA-B27-positive Caucasian populations were selected, one from Spain (71 patients and 105 controls) and another from the Azores (Portugal) (55 patients and 75 controls). All were typed for HLA-B and KIR (3DS1 and 3DL1) genes. Our results show that in addition to B27, the allele 3DS1 is associated with AS compared with B27 controls (p < 0.0001 and p < 0.003 in the Spanish population and Azoreans, respectively). We also observed that the association of KIR3DS1 to AS was found in combination with HLA-B alleles carrying Bw4-I80 in trans position in the Spanish population (30.9% in AS versus 15.2% in B27 controls, p = 0.02, odds ratio (OR) = 2.49) and in Azoreans (27.2% in AS versus 8.7% in B27 controls, p = 0.01, OR = 4.4 in Azoreans). On the other hand, 3DL1 was decreased in patients compared with B27 controls (p < 0.0001 in the Spanish population and p < 0.003 in Azoreans). The presence of this allele in combination with Bw4-I80 had a protective effect against the development of AS in the Spanish population (19.7% in AS, 35.2% in B27 controls; p = 0.03, OR = 0.45). The presence of KIR3DS1 or KIR3DL1 in combination with HLA-B*27s/HLA-B Bw4-I80 genotypes may modulate the development of AS. The susceptibility to AS could be determined by the overall balance of activating and inhibitory composite KIR-HLA genotypes. PMID:16805919
Alderling, Magnus; Theorell, Töres; de la Torre, Bartolomé; Lundberg, Ingvar
2006-01-01
Background Previous studies of the relationship between job strain and blood or saliva cortisol levels have been small and based on selected occupational groups. Our aim was to examine the association between job strain and saliva cortisol levels in a population-based study in which a number of potential confounders could be adjusted for. Methods The material derives from a population-based study in Stockholm on mental health and its potential determinants. Two data collections were performed three years apart with more than 8500 subjects responding to a questionnaire in both waves. In this paper our analyses are based on 529 individuals who held a job, participated in both waves as well as in an interview linked to the second wave. They gave saliva samples at awakening, half an hour later, at lunchtime and before going to bed on a weekday in close connection with the interview. Job control and job demands were assessed from the questionnaire in the second wave. Mixed models were used to analyse the association between the demand control model and saliva cortisol. Results Women in low strain jobs (high control and low demands) had significantly lower cortisol levels half an hour after awakening than women in high strain (low control and high demands), active (high control and high demands) or passive jobs (low control and low demands). There were no significant differences between the groups during other parts of the day and furthermore there was no difference between the job strain, active and passive groups. For men, no differences were found between demand control groups. Conclusion This population-based study, on a relatively large sample, weakly support the hypothesis that the demand control model is associated with saliva cortisol concentrations. PMID:17129377
Barnes, Kayla G; Weedall, Gareth D; Ndula, Miranda; Irving, Helen; Mzihalowa, Themba; Hemingway, Janet; Wondji, Charles S
2017-02-01
Insecticide resistance in mosquito populations threatens recent successes in malaria prevention. Elucidating patterns of genetic structure in malaria vectors to predict the speed and direction of the spread of resistance is essential to get ahead of the 'resistance curve' and to avert a public health catastrophe. Here, applying a combination of microsatellite analysis, whole genome sequencing and targeted sequencing of a resistance locus, we elucidated the continent-wide population structure of a major African malaria vector, Anopheles funestus. We identified a major selective sweep in a genomic region controlling cytochrome P450-based metabolic resistance conferring high resistance to pyrethroids. This selective sweep occurred since 2002, likely as a direct consequence of scaled up vector control as revealed by whole genome and fine-scale sequencing of pre- and post-intervention populations. Fine-scaled analysis of the pyrethroid resistance locus revealed that a resistance-associated allele of the cytochrome P450 monooxygenase CYP6P9a has swept through southern Africa to near fixation, in contrast to high polymorphism levels before interventions, conferring high levels of pyrethroid resistance linked to control failure. Population structure analysis revealed a barrier to gene flow between southern Africa and other areas, which may prevent or slow the spread of the southern mechanism of pyrethroid resistance to other regions. By identifying a genetic signature of pyrethroid-based interventions, we have demonstrated the intense selective pressure that control interventions exert on mosquito populations. If this level of selection and spread of resistance continues unabated, our ability to control malaria with current interventions will be compromised.
Yang, Zhi-Qi; Zhao, Qi; Jiang, Ping; Zheng, Song-Bai; Xu, Biao
2017-12-28
Hypertension is considered a major public health challenge. It is the most important risk factor for cardiovascular disease and is a prominent risk for China's elderly population. However, few studies have addressed the effect of blood pressure control on elderly hypertension patients in China. In response, this study aimed to investigate the prevalence and control of hypertension in the elderly population in Shanghai's communities. A secondary data analysis based on a government-financed health check-up program for an elderly population aged 65 and older from 2012 to 2014 was conducted in a central district of Shanghai. Of the 44,978 study participants, 20,305 (45.1%) were males and 24,673 (54.9%) were females. The participants' median age was 72. Half of the participants were overweight or obese (BMI ≥ 24.0 kg/m 2 ). The prevalence of hypertension was 59.9%. In the 18,032 participants without prior diagnosis of hypertension, 5530 (30.7%) had increased blood pressure. Among the 26,946 confirmed hypertension patients, the proportions of treatment and blood pressure control were 32.8% and 43.4% respectively. Multivariate analysis showed that the uncontrolled hypertension was significantly associated with older age, being overweight or obese, a lower level of education, an unbalanced dietary pattern, regular drinking and non-comorbidities. The prevalence of hypertension was high in China's elderly population. The proportion of individuals who received treatment remained low, and blood pressure control was poor among hypertension patients. These results indicate that improvement of the ability to manage and control hypertension among urban elderly residents is urgently needed.
Targeting male mosquito swarms to control malaria vector density
Sawadogo, Simon Peguedwinde; Niang, Abdoulaye; Bilgo, Etienne; Millogo, Azize; Maïga, Hamidou; Dabire, Roch K.; Tripet, Frederic; Diabaté, Abdoulaye
2017-01-01
Malaria control programs are being jeopardized by the spread of insecticide resistance in mosquito vector populations. It has been estimated that the spread of resistance could lead to an additional 120000 deaths per year, and interfere with the prospects for sustained control or the feasibility of achieving malaria elimination. Another complication for the development of resistance management strategies is that, in addition to insecticide resistance, mosquito behavior evolves in a manner that diminishes the impact of LLINs and IRS. Mosquitoes may circumvent LLIN and IRS control through preferential feeding and resting outside human houses and/or being active earlier in the evening before people go to sleep. Recent developments in our understanding of mosquito swarming suggest that new tools targeting mosquito swarms can be designed to cut down the high reproductive rate of malaria vectors. Targeting swarms of major malaria vectors may provide an effective control method to counteract behavioral resistance developed by mosquitoes. Here, we evaluated the impact of systematic spraying of swarms of Anopheles gambiae s.l. using a mixed carbamate and pyrethroid aerosol. The impact of this intervention on vector density, female insemination rates and the age structure of males was measured. We showed that the resulting mass killing of swarming males and some mate-seeking females resulted in a dramatic 80% decrease in population size compared to a control population. A significant decrease in female insemination rate and a significant shift in the age structure of the male population towards younger males incapable of mating were observed. This paradigm-shift study therefore demonstrates that targeting primarily males rather than females, can have a drastic impact on mosquito population. PMID:28278212
Optimal control of population and coherence in three-level Λ systems
NASA Astrophysics Data System (ADS)
Kumar, Praveen; Malinovskaya, Svetlana A.; Malinovsky, Vladimir S.
2011-08-01
Optimal control theory (OCT) implementations for an efficient population transfer and creation of maximum coherence in a three-level system are considered. We demonstrate that the half-stimulated Raman adiabatic passage scheme for creation of the maximum Raman coherence is the optimal solution according to the OCT. We also present a comparative study of several implementations of OCT applied to the complete population transfer and creation of the maximum coherence. Performance of the conjugate gradient method, the Zhu-Rabitz method and the Krotov method has been analysed.
Ryon, A.D.; Haas, P.A.; Vavruska, J.S.
1982-01-19
The present invention is directed to a method and apparatus for making a population of dense, closely size-controlled microspheres by sol-gel procedures wherein said microspheres are characterized by a significant percentage of said population being within a predetermined, relatively narrow size range. This is accomplished by subjecting aqueous dispersions of a sol, within a water-immiscible organic liquid to a turbulent flow. Microsphere populations thus provided are useful in vibratory-packed processes for nuclear fuels to be irradiated in LWR- and FBR-type nuclear reactors.
Population control of the malaria vector Anopheles pseudopunctipennis by habitat manipulation.
Bond, J. Guillermo; Rojas, Julio C.; Arredondo-Jiménez, Juan I.; Quiroz-Martínez, Humberto; Valle, Javier; Williams, Trevor
2004-01-01
Insect vector-borne diseases continue to present a major challenge to human health. Understanding the factors that regulate the size of mosquito populations is considered fundamental to the ability to predict disease transmission rates and for vector population control. The mosquito, Anopheles pseudopunctipennis, a vector of Plasmodium spp., breeds in riverside pools containing filamentous algae in Mesoamerica. Breeding pools along 3 km sections of the River Coatan, Chiapas, Mexico were subjected to algal extraction or left as controls in a cross-over trial extending over 2 years. Initial densities of An. pseudopunctipennis larvae were directly proportional to the prevalence of filamentous algae in each breeding site. The extraction of algae brought about a striking decline in the density of An. pseudopunctipennis larvae sustained for about six weeks, and a concurrent reduction in the adult population in both years of the study. Mark-release experiments indicated that dispersal from adjacent untreated areas was unlikely to exert an important influence on the magnitude of mosquito control that we observed. Habitat manipulation by extraction of filamentous algae offers a unique opportunity for sustainable control of this malaria vector. This technique may represent a valuable intervention, complimenting insecticide spraying of households, to minimize Plasmodium transmission rates in Mesoamerica. PMID:15475337
Fatima, Ambrin; Farooq, Muhammad; Abdullah, Uzma; Tariq, Muhammad; Mustafa, Tanveer; Iqbal, Muhammad; Tommerup, Niels; Mahmood Baig, Shahid
2017-09-01
Schizophrenia is a chronic neuropsychiatric disease afflicting around 1.1% of the population worldwide. Recently, MIR137 , CACNA1C , CSMD1 , DRD2 , and GRM3 have been reported as the most robustly emerging candidates involved in the etiology of schizophrenia. In this case control study, we performed an association analysis of rs1625579 ( MIR137 ), rs1006737, rs4765905 ( CACNA1C ), rs10503253 ( CSMD1 ), rs1076560 ( DRD2 ), rs12704290, rs6465084, and rs148754219 ( GRM3 ) in Pakistani population. Schizophrenia was diagnosed on the basis of the Diagnostic and Statistical Manual of Mental Disorders 4th ed (DSM-IV). Detailed clinical information, family history of all patients and healthy controls were collected. RFLP based case control association study was performed in a Pakistani cohort of 508 schizophrenia patients and 300 healthy control subjects. Alleles and genotype frequencies were calculated using SPSS. A significant difference in the genotype and allele frequencies for rs4765905, rs1076560 and rs6465084 were found between the patients and controls (p=0.000). This study provides substantial evidence supporting the role of CACNA1C , GRM3 and DRD2 as schizophrenia susceptibility genes in Pakistani population.
Discourse on malaria elimination: where do forcibly displaced persons fit in these discussions?
2013-01-01
Background Individuals forcibly displaced are some of the poorest people in the world, living in areas where infrastructure and services are at a bare minimum. Out of a total of 10,549,686 refugees protected and assisted by the United Nations High Commissioner for Refugees globally, 6,917,496 (65.6%) live in areas where malaria is transmitted. Historically, national malaria control programmes have excluded displaced populations. Results The current discourse on malaria elimination rarely includes discussion of forcibly displaced persons who reside within malaria-eliminating countries. Of the 100 malaria-endemic countries, 64 are controlling malaria and 36 are in some stage of elimination. Of these, 30 malaria-controlling countries and 13 countries in some phase of elimination host displaced populations of ≥50,000, even though 13 of the 36 (36.1%) malaria-elimination countries host displaced populations of ≥50,000 people. Discussion Now is the time for the malaria community to incorporate forcibly displaced populations residing within malarious areas into malaria control activities. Beneficiaries, whether they are internally displaced persons or refugees, should be viewed as partners in the delivery of malaria interventions and not simply as recipients. Conclusion Until equitable and sustainable malaria control includes everyone residing in an endemic area, the goal of malaria elimination will not be met. PMID:23575209
Lysenkoism and the population control movement.
Simon, J L
1997-09-01
The case of Lysenkoism in the Soviet Union helps us understand how people's wrong beliefs can be influenced by what the information they receive from outside, especially when there is a large volume of media coverage and there is no contrary information to be heard. The population control movement in contemporary United States has many parallels to the Lysenko episode.
Using new technology and insect behavior in novel terrestrial and flying insect traps
USDA-ARS?s Scientific Manuscript database
Insect traps are commonly used for both population sampling and insect control, the former as part of an integrated pest management (IPM) program. We developed traps for two insects, one as part of a pesticide based IPM system and the other for population control. Our IPM trap is for crawling insect...
Impulsive Vaccination for an Epidemiology Model
NASA Astrophysics Data System (ADS)
De la Sen, M.; Garrido, A. J.
2017-03-01
This paper investigates sufficient conditions of almost periodic sand periodic solutions of an integral model under impulsive controls. Since the model is of generic epidemiological interest, such impulsive controls are either vaccination actions or abrupt variations of the infected population due to infected immigration or lost of infective numbers due to either vaccination or lost of infected population by out-migration.
Effects of Internal Border Control on Spread of Pandemic Influenza
Zamani, Nasim; MacIntyre, C. Raina; Becker, Niels G.
2007-01-01
We investigated the capacity of internal border control to limit influenza spread in an emergent pandemic in the context of Australia, a country with a low-population density and geopolitical boundaries that may facilitate restrictions. Mathematical models were used to study the time delay between epidemics in 2 population centers when travel restrictions were imposed. The models demonstrated that population size, travel rates, and places where travelers reside can strongly influence delay. The model simulations suggested that moderate delays in geographic spread may be possible with stringent restrictions and a low reproduction number, but results will be sensitive to the reproduction number and timing of restrictions. Model limitations include the absence of further importations and additional control measures. Internal border control may have a role in protecting domestic centers early in a pandemic, when importations are sparse. Our results may be useful for policymakers. PMID:18214176
Abe, Eniola Michael; Guan, Wei; Guo, Yun-Hai; Kassegne, Kokouvi; Qin, Zhi-Qiang; Xu, Jing; Chen, Jun-Hu; Ekpo, Uwem Friday; Li, Shi-Zhu; Zhou, Xiao-Nong
2018-03-26
Snail intermediate hosts play active roles in the transmission of snail-borne trematode infections in Africa. A good knowledge of snail-borne diseases epidemiology particularly snail intermediate host populations would provide the necessary impetus to complementing existing control strategy. This review highlights the importance of molecular approaches in differentiating snail hosts population structure and the need to provide adequate information on snail host populations by updating snail hosts genome database for Africa, in order to equip different stakeholders with adequate information on the ecology of snail intermediate hosts and their roles in the transmission of different diseases. Also, we identify the gaps and areas where there is need for urgent intervention to facilitate effective integrated control of schistosomiasis and other snail-borne trematode infections. Prioritizing snail studies, especially snail differentiation using molecular tools will boost disease surveillance and also enhance efficient schistosomaisis control programme in Africa.
Synthesizing epidemiological and economic optima for control of immunizing infections.
Klepac, Petra; Laxminarayan, Ramanan; Grenfell, Bryan T
2011-08-23
Epidemic theory predicts that the vaccination threshold required to interrupt local transmission of an immunizing infection like measles depends only on the basic reproductive number and hence transmission rates. When the search for optimal strategies is expanded to incorporate economic constraints, the optimum for disease control in a single population is determined by relative costs of infection and control, rather than transmission rates. Adding a spatial dimension, which precludes local elimination unless it can be achieved globally, can reduce or increase optimal vaccination levels depending on the balance of costs and benefits. For weakly coupled populations, local optimal strategies agree with the global cost-effective strategy; however, asymmetries in costs can lead to divergent control optima in more strongly coupled systems--in particular, strong regional differences in costs of vaccination can preclude local elimination even when elimination is locally optimal. Under certain conditions, it is locally optimal to share vaccination resources with other populations.
Van Houtven, Courtney H; Greiner, Melissa A; Heidenfelder, Brooke; Spratt, Susan E; Granger, Bradi B; Dunham, Ashley A; Qualls, Laura G; Curtis, Lesley H
2018-04-01
Type 2 diabetes mellitus imposes significant burdens on patients and health care systems. Population-level interventions are being implemented to reach large numbers of patients at risk of or diagnosed with diabetes. We describe a population-based evaluation of the Southeastern Diabetes Initiative (SEDI) from the perspective of a payer, the Centers for Medicare & Medicaid Services (CMS). The purpose of this paper is to describe the population-based evaluation approach of the SEDI intervention from a Medicare utilization and cost perspective. We measured associations between the SEDI intervention and receipt of diabetes screening (i.e., HbA1c test, eye exam, lipid profile), health care resource use, and costs among intervention enrollees, compared with a control cohort of Medicare beneficiaries in geographically adjacent counties. The intervention cohort had slightly lower 1-year screening in 2 of 3 domains (4% for HbA1c; 9% for lipid profiles) in the post-intervention period, compared with the control cohort. The SEDI intervention cohort did not have different Medicare utilization or total Medicare costs in the post-intervention period from surrounding control counties. Our analytic approach may be useful to others evaluating CMS demonstration projects in which population-level health is targeted for improvement in a well-defined clinical population. Published by Elsevier Ltd.
Baghaei, Abdolmehdi; Rabiei, Katayoun; Gharipour, Mojgan; Tavasoli, Ali Akbar; Shirani, Shahin; Bahonar, Ahamad; Davarpanah, Amir Hossein; Ramezani, Mohammad Arash; Kelishadi, Roya
2010-01-01
Introduction The Isfahan Healthy Heart Programme (IHHP) is a community-based programme for non-communicable diseases prevention and control using both a population and high risk approach in Iran. This study demonstrated the efficacy of IHHP interventional strategies to improve lifestyle behaviours in a population at risk for developing cardiovascular diseases. Material and methods Healthy Lifestyle for NCDs High Risk Population is one of ten projects of IHHP. High risk individuals were defined as those who have at least one risk factor for developing coronary artery disease (CAD). Changes of behavioural indicators have been compared between two areas with a survey after 5 years of intervention. Results Among high risk individuals in the intervention and reference areas, 77.8% and 82.5% had at least one major risk factor for CAD. The prevalence of major risk factors for CAD (except cigarette smoking) was decreased in both intervention and reference areas during 5 years of intervention and the pattern of diet and physical activity was improved. Conclusions Interventional activities in IHHP targeting the high risk population seem to be effective in improving lifestyle behaviour, increasing awareness and control of risk factors of the high risk population. PMID:22371716
Adiabatic Quantum Computation: Coherent Control Back Action.
Goswami, Debabrata
2006-11-22
Though attractive from scalability aspects, optical approaches to quantum computing are highly prone to decoherence and rapid population loss due to nonradiative processes such as vibrational redistribution. We show that such effects can be reduced by adiabatic coherent control, in which quantum interference between multiple excitation pathways is used to cancel coupling to the unwanted, non-radiative channels. We focus on experimentally demonstrated adiabatic controlled population transfer experiments wherein the details on the coherence aspects are yet to be explored theoretically but are important for quantum computation. Such quantum computing schemes also form a back-action connection to coherent control developments.
Guidelines for management of noxious weeds at Hanford
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roos, R.C.; Malady, M.B.
1995-10-27
Integrated Pest Management Services is responsible for management and control of noxious weeds on the Hanford Site. Weed species and populations are prioritized and objective defined, according to potential site and regional impact. Population controls are implemented according to priority. An integrated approach is planned for noxious weed control in which several management options are considered and implemented separately or in coordination to best meet management objectives. Noxious weeds are inventories and monitored to provide information for planning and program review.
[Population trends in Albania].
Sivignon, M
1983-01-01
Recent demographic trends in Albania are reviewed. The author notes that rapid population growth persists due to continuing fertility, although the fertility rate has begun to decline during the past 20 years. Controls placed on internal migration have succeeded in restricting the growth of the urban population and have contributed to the sustained growth of the population in rural areas. (summary in ENG)
World Population: U.N. on the Move but Grounds for Optimism Are Scant
ERIC Educational Resources Information Center
Holden, Constance
1974-01-01
Discusses current trends and problems relating to world population, and focuses on action being taken by the United Nations. This year (1974) has been designated World Population Year, and will be highlighted by a conference in Bucharest in which all 130 member governments will meet to confront the issue of population control. (JR)
Ground-based rodent control in a remote Hawaiian rainforest on Maui
Malcolm, T.R.; Swinnerton, K.J.; Groombridge, J.J.; Sparklin, B.D.; Brosius, C.N.; Vetter, J.P.; Foster, J.T.
2008-01-01
Effective control of introduced mammalian predators is essential to the recovery of native bird species in Hawai'i. Between August 1996 and December 2004, introduced rodents were controlled within three home ranges of the Po'ouli Melamprosops phaeosoma, a critically endangered Hawaiian honeycreeper. Rats were controlled using a combination of ground-based rodenticide (0.005% diphacinone) application and snap traps. Beginning in August 2001, we monitored the effectiveness of these rodent control efforts. Relative abundances of Black Rats Rattus rattus and Polynesian Rats R. exulans were measured in each of five snap-trapping grids seven times over a 35-month period. Rat populations decreased inside of the rodent control areas, but control effectiveness differed between rat species. During the first year of monitoring, target control levels for R. rattus were consistently achieved in only one of the rodent control areas. Control techniques were refined in areas failing to meet targets. Subsequently, we achieved target control levels for R. rattus more consistently in all three rodent control areas. However, relative abundances of R. exulans did not differ between rodent control and reference areas, indicating that our rodent control techniques were insufficient to reduce population levels of this species. These findings signify a need for further improvement of rodent control methods in Hawai'i, especially for Polynesian Rats, and demonstrate the critical importance of periodic monitoring of the response of rodent populations to management. In the future, managers may need to design rodent control operations targeting R. rattus and R. exulans independently to achieve best results.
Tribe, Andrew; Hanger, Jon; McDonald, Ian J; Loader, Jo; Nottidge, Ben J; McKee, Jeff J; Phillips, Clive J C
2014-09-15
Traditionally, culling has been the expedient, most common, and in many cases, the only tool used to control free-ranging kangaroo populations. We applied a reproductive control program to a population of eastern grey kangaroos confined to a golf course in South East Queensland. The program aimed to reduce fecundity sufficiently for the population to decrease over time so that overgrazing of the fairways and the frequency of human-animal conflict situations were minimised. In 2003, 92% of the female kangaroos above 5 kg bodyweight were implanted with the GnRH agonist deslorelin after darting with a dissociative anaesthetic. In 2007, 86% of the females above 5 kg were implanted with deslorelin and also 87% of the males above 5 kg were sterilised by either orchidectomy or vasectomy. In 2005, 2008 and 2009, the population was censused to assess the effect of each treatment. The 2003 deslorelin program resulted in effective zero population growth for approximately 2.5 years. The combined deslorelin-surgery program in 2007 reduced the birth rate from 0.3 to 0.06%/year for 16 months, resulting in a 27% population reduction by November 2009. The results were consistent with implants conferring contraception to 100% of implanted females for at least 12 months. The iatrogenic mortality rates for each program were 10.5% and 4.9%, respectively, with 50% of all mortalities due to darting-related injuries, exertional myopathy/hyperthermia or recovery misadventure. The short term sexual and agonistic behaviour of the males was assessed for the 2007 program: no significant changes were seen in adult males given the vasectomy procedure, while sexual behaviours' were decreased in adult males given the orchidectomy procedure. It is concluded that female reproduction was effectively controlled by implantation with deslorrelin and male reproductive behaviour was reduced by orchidectomy, which together achieved population control.
Is population flow an unintended consequence of alcohol management plans?
Usher, Kim; Woods, Cindy; Lynch, Paul; Pointing, Shane Boris; Budden, Lea; Barker, Ruth; Catchpoole, Jesani; Clough, Alan
2017-03-01
The aim of this study was to gauge whether, and to what extent, population flow occurred as a result of the implementation of alcohol management plans in Indigenous communities. Alcohol management plans involving carriage limits and dry places were introduced into 15 Queensland Indigenous communities between 2002-2004. Controls on alcohol availability were further tightened between 2008-2010, seeing the closure of eight mainly remote community taverns/canteens. A retrospective observational study was undertaken using data from the Queensland Injury Surveillance Unit. Population flow was measured by changing patterns of alcohol-related injuries in a mining region near dry Indigenous communities following the introduction of alcohol management plans and a control mining region distant from Indigenous communities with alcohol management plans. Data were analysed using descriptive and inferential statistics. Logistic regression was used for the comparison of the characteristics between the emergency department presentations. The rates of alcohol-related injury presentations per 1000/population were calculated and age-standardised to the Australian population. Between the five-year periods 2003-2007 and 2008-2012, alcohol-related injury presentations to the Mount Isa emergency department trebled from an age-adjusted average annual rate of 9·5/1000 in the region's population to 27·1/1000 population. In the control region, alcohol-related emergency department injury presentations did not increase to the same degree with age-adjusted average annual rates of 1·42/1000 and 2·21/1000, respectively. The 10-year pattern of emergency department presentations for alcohol-related injuries increased significantly in the Mount Isa region compared with the control region. Further research should investigate the impacts of population flow related to Indigenous community alcohol management plans. Although initiatives such as alcohol management plans have been implemented to reduce alcohol use and related consequences in Indigenous communities, there needs to be a greater consideration of the impact of these policies in nearby towns in the future. © 2016 John Wiley & Sons Ltd.
Castanon Romo, R; Sandoval Navarrete, J
1996-01-01
This broad survey of the debate concerning the relationship between population growth and economic development discusses the history and current status of world population growth, summarizes several influential theoretical positions on the topic, and proposes that redefinition of women's social role is indispensable if worldwide control of population growth is to be achieved. The introductory section discusses the acceleration of population growth in the second half of the 20th century and the increasing concentration of growth in the poor and developing countries. The positions of those who see in population control a means of promoting economic development and political stability are contrasted to the positions of those who believe that a large and growing population is the key to achieving economic and political progress. The international community, facing great uncertainty about the size, distribution, and well-being of the future world population, is increasingly concerned about the effect of growing numbers on the environment and natural resources. The second section summarizes the works of Malthus, Julian Simon, and the Club of Rome, and analyzes the propositions of demographic transition theory. The conclusion notes that despite uncertainty about the future of world population, development, and health, most of the poorest countries have become aware of the desirability of slowing population growth. A broad redefinition of the social role of women will inevitably accompany the worldwide demographic transition.
Hwang, Chiachi; Wu, Weimin; Gentry, Terry J; Carley, Jack; Corbin, Gail A; Carroll, Sue L; Watson, David B; Jardine, Phil M; Zhou, Jizhong; Criddle, Craig S; Fields, Matthew W
2009-01-01
Bacterial community succession was investigated in a field-scale subsurface reactor formed by a series of wells that received weekly ethanol additions to re-circulating groundwater. Ethanol additions stimulated denitrification, metal reduction, sulfate reduction and U(VI) reduction to sparingly soluble U(IV). Clone libraries of SSU rRNA gene sequences from groundwater samples enabled tracking of spatial and temporal changes over a 1.5-year period. Analyses showed that the communities changed in a manner consistent with geochemical variations that occurred along temporal and spatial scales. Canonical correspondence analysis revealed that the levels of nitrate, uranium, sulfide, sulfate and ethanol were strongly correlated with particular bacterial populations. As sulfate and U(VI) levels declined, sequences representative of sulfate reducers and metal reducers were detected at high levels. Ultimately, sequences associated with sulfate-reducing populations predominated, and sulfate levels declined as U(VI) remained at low levels. When engineering controls were compared with the population variation through canonical ordination, changes could be related to dissolved oxygen control and ethanol addition. The data also indicated that the indigenous populations responded differently to stimulation for bioreduction; however, the two biostimulated communities became more similar after different transitions in an idiosyncratic manner. The strong associations between particular environmental variables and certain populations provide insight into the establishment of practical and successful remediation strategies in radionuclide-contaminated environments with respect to engineering controls and microbial ecology.
Chen, Cheng; Xun, Pengcheng; Nishijo, Muneko; He, Ka
2016-09-01
The association between cadmium exposure and risk of lung cancer is still unclear. We quantitatively reviewed the observational studies that investigated the association between cadmium exposure and lung cancer risk in both general and occupational populations published through April 2015. The final data set is comprised of three cohort studies in the general population totaling 22,551 participants (354 events) with a mean follow-up of 15 years, five occupational cohort studies including 4205 individuals (180 events) with an average follow-up of 31 years, and three occupational case-control studies including 4740 cases and 6268 controls. Comparing the highest to the lowest category of cadmium exposure, the weighted relative risk and 95% confidence interval of lung cancer in the general population was 1.42 (95% CI (0.91, 2.23)); the weighted risk estimates (95% CIs) of lung cancer in three occupational cohort studies and three case-control studies were 0.68 (95% CI (0.33, 1.41)) and 1.61 (95% CI (0.94, 2.75)), respectively. No linear association was found. When comparing participants exposed to cadmium with non-exposed based on available data, the association became statistically significant. According to findings from this meta-analysis, the possibility that cadmium exposure may increase risk of lung cancer cannot be completely ruled out in either general or occupational population.
Jiménez-Villarreal, J; Rivas-Armendariz, D I; Pineda-Belmontes, C P; Betancourt-Martínez, N D; Macías-Corral, M A; Guerra-Alanis, A J; Niño-Castañeda, M S; Morán-Martínez, J
2017-05-18
Different studies have suggested an association between arsenic (As) exposure and damage to single-stranded DNA by reactive oxygen species derived from the biotransformation of arsenic. The single strand damages are converted to double strand damage upon interaction with ultraviolet radiation. Analysis of genomic integrity is important for assessing the genotoxicity caused by environmental pollutants. In this study, we compared the concentration of As in drinking water, nutritional status, lifestyle variables, and the level of genotoxicity in an exposed population and a control group. Arsenic content of water was determined using a portable Arsenator ® kit. DNA fragmentation was determined using the two-tailed comet assay. Our results show that the exposed population had low nutritional consumption compared to the control group (P < 0.05). Furthermore, the water consumed by the exposed group had As concentration of 14.3 ± 8.4 mg/L, whereas the As level in the water consumed by the control group was 7.7 ± 3.5 mg/L. Analysis shows that the frequency of double strand break (DSB) fragmentation was higher in the population exposed to higher levels of As compared to that of the control group. These results suggest a possible association between the concentration of As in drinking water and lifestyle variables, with increasing fragmentation of DSBs in the exposed population.
Coupling Financial Incentives With Direct Mail in Population-Based Practice.
Slater, Jonathan S; Parks, Michael J; Malone, Michael E; Henly, George A; Nelson, Christina L
2017-02-01
Financial incentives are being used increasingly to encourage a wide array of health behaviors because of their well-established efficacy. However, little is known about how to translate incentive-based strategies to public health practice geared toward improving population-level health, and a dearth of research exists on how individuals respond to incentives through public health communication strategies such as direct mail. This study reports results of a population-based randomized controlled trial testing a direct mail, incentive-based intervention for promoting mammography uptake. The study population was composed of a random sample of Minnesota women enrolled in Medicare fee-for-service and overdue for breast cancer screening. Participants ( N = 18,939) were randomized into three groups: (1) Direct Mail only, (2) Direct Mail plus Incentive, and (3) Control. Both direct mail groups received two mailers with a message about the importance of mammography; however, Mail plus Incentive mailers also offered a $25 incentive for getting a mammogram. Logistic regression analyses measured intervention effects. Results showed the odds for receiving mammography were significantly higher for the Direct Mail plus Incentive group compared with both Direct Mail only and Control groups. The use of incentives also proved to be cost-effective. Additionally, the Direct Mail only group was more likely to receive mammography than the Control group. Findings offer experimental evidence on how the population-based strategy of direct mail coupled with a financial incentive can encourage healthy behavior, as well as how incentive-based programs can be translated into health promotion practice aimed at achieving population-level impact.
Resistance to genetic insect control: Modelling the effects of space.
Watkinson-Powell, Benjamin; Alphey, Nina
2017-01-21
Genetic insect control, such as self-limiting RIDL 2 (Release of Insects Carrying a Dominant Lethal) technology, is a development of the sterile insect technique which is proposed to suppress wild populations of a number of major agricultural and public health insect pests. This is achieved by mass rearing and releasing male insects that are homozygous for a repressible dominant lethal genetic construct, which causes death in progeny when inherited. The released genetically engineered ('GE') insects compete for mates with wild individuals, resulting in population suppression. A previous study modelled the evolution of a hypothetical resistance to the lethal construct using a frequency-dependent population genetic and population dynamic approach. This found that proliferation of resistance is possible but can be diluted by the introgression of susceptible alleles from the released homozygous-susceptible GE males. We develop this approach within a spatial context by modelling the spread of a lethal construct and resistance trait, and the effect on population control, in a two deme metapopulation, with GE release in one deme. Results show that spatial effects can drive an increased or decreased evolution of resistance in both the target and non-target demes, depending on the effectiveness and associated costs of the resistant trait, and on the rate of dispersal. A recurrent theme is the potential for the non-target deme to act as a source of resistant or susceptible alleles for the target deme through dispersal. This can in turn have a major impact on the effectiveness of insect population control. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Segregation for fertility and meiotic stability in novel Brassica allohexaploids.
Mwathi, Margaret W; Gupta, Mehak; Atri, Chaya; Banga, Surinder S; Batley, Jacqueline; Mason, Annaliese S
2017-04-01
Allohexaploid Brassica populations reveal ongoing segregation for fertility, while genotype influences fertility and meiotic stability. Creation of a new Brassica allohexaploid species is of interest for the development of a crop type with increased heterosis and adaptability. At present, no naturally occurring, meiotically stable Brassica allohexaploid exists, with little data available on chromosome behaviour and meiotic control in allohexaploid germplasm. In this study, 100 plants from the cross B. carinata × B. rapa (A2 allohexaploid population) and 69 plants from the cross (B. napus × B. carinata) × B. juncea (H2 allohexaploid population) were assessed for fertility and meiotic behaviour. Estimated pollen viability, self-pollinated seed set, number of seeds on the main shoot, number of pods on the main shoot, seeds per ten pods and plant height were measured for both the A2 and H2 populations and for a set of reference control cultivars. The H2 population had high segregation for pollen viability and meiotic stability, while the A2 population was characterised by low pollen fertility and a high level of chromosome loss. Both populations were taller, but had lower average fertility trait values than the control cultivar samples. The study also characterises fertility and meiotic chromosome behaviour in genotypes and progeny sets in heterozygous allotetraploid Brassica derived lines, and indicates that genotypes of the parents and H1 hybrids are affecting chromosome pairing and fertility phenotypes in the H2 population. The identification and characterisation of factors influencing stability in novel allohexaploid Brassica populations will assist in the development of this as a new crop species for food and agricultural benefit.
Bhaskar, Lakkakula V K S; Thangaraj, Kumarasamy; Wasnik, Samiksha; Singh, Lalji; Raghavendra Rao, Vadlamudi
2012-01-01
It is well established that the central dopaminergic reward pathway is likely involved in alcohol intake and the progression of alcohol dependence. Dopamine transporter (DAT1) mediates the active re-uptake of DA from the synapse and is a principal regulator of dopaminergic neurotransmission. The gene for the human DAT1 displays several polymorphisms, including a 40-bp variable number of tandem repeats (VNTR) ranging from 3 to 16 copies in the 3'-untranslated region (UTR) of the gene. To assess the role of this gene in alcoholism, we genotyped the VNTR of DAT1 gene in a sample of 206 subjects from the Kota population (111 alcohol dependence cases and 95 controls) and 142 subjects from Badaga population (81 alcohol dependence cases and 61 controls). Both populations inhabit a similar environmental zone, but have different ethnic histories. Phenotype was defined based on the DSM-IV criteria. Genotyping was performed using PCR and electrophoresis. The association of DAT1 with alcoholism was tested by using the Clump v1.9 program which uses the Monte Carlo method. In both Kota and Badaga populations, the allele A10 was the most frequent allele followed by allele A9. The genotypic distribution is in Hardy-Weinberg equilibrium in both cases and control groups of Kota and Badaga populations. The DAT1 VNTR was significantly associated with alcoholism in Badaga population but not in Kota population. Our results suggest that the A9 allele of the DAT gene is involved in vulnerability to alcoholism, but that these associations are population specific. Copyright © American Academy of Addiction Psychiatry.
2013-01-01
Background Recruitment of controls remains a challenge in case–control studies and particularly in studies involving minority populations. Methods We compared characteristics of controls recruited through random digit dialing (RDD) to those of community controls enrolled through churches, health events and other outreach sources among women of African ancestry (AA) participating in the Women’s Circle of Health Study, a case–control study of breast cancer. Odds ratios and 95% confidence intervals were also computed using unconditional logistic regression to evaluate the impact of including the community controls for selected variables relevant to breast cancer and for which there were significant differences in distribution between the two control groups. Results Compared to community controls (n=347), RDD controls (n=207) had more years of education and higher income, lower body mass index, were more likely to have private insurance, and less likely to be single. While the percentage of nulliparous women in the two groups was similar, community controls tended to have more children, have their first child at a younger age, and were less likely to breastfeed their children. Dietary intake was similar in the two groups. Compared to census data, the combination of RDD and community controls seems to be more representative of the general population than RDD controls alone. Furthermore, the inclusion of the community group had little impact on the magnitude of risk estimates for most variables, while enhancing statistical power. Conclusions Community-based recruitment was found to be an efficient and feasible method to recruit AA controls. PMID:23721229
Neuropsychologic assessment of a population-based sample of Gulf War veterans.
Wallin, Mitchell T; Wilken, Jeffrey; Alfaro, Mercedes H; Rogers, Catherine; Mahan, Clare; Chapman, Julie C; Fratto, Timothy; Sullivan, Cynthia; Kang, Han; Kane, Robert
2009-09-01
The objective of this project was to compare neuropsychologic performance and quality of life in a population-based sample of deployed Gulf War (GW) veterans with and without multisymptom complaints. The study participants were obtained from the 30,000 member population-based National Health Survey of GW-era veterans conducted in 1995. Cases (N=25) were deployed to the year 1990 and 1991 GW and met Center for Disease Control and Prevention criteria for multisymptom GW illness (GWI). Controls (N=16) were deployed to the 1990 and 1991 GW but did not meet Center for Disease Control and Prevention criteria for GWI. There were no significant differences in composite scores on the traditional and computerized neuropsychologic battery (automated neuropsychologic assessment metrics) between GW cases and controls using bivariate techniques. Multiple linear regression analyses controlling for demographic and clinical variables revealed composite automated neuropsychologic assessment metrics scores were associated with age (b=-7.8; P=0.084), and education (b=22.9; P=0.0012), but not GW case or control status (b=-63.9; P=0.22). Compared with controls, GW cases had significantly more impairment on the Personality Assessment Inventory and the short form-36. Compared with GW controls, GW cases meeting criteria for GWI had preserved cognition function but had significant psychiatric symptoms and lower quality of life.
Jones, Jennifer D
2006-01-01
The use of a control group is fundamental to experimental research design, though the use with clinical populations must be carefully considered. The purpose of this research was to examine the use of control groups in research with clinical and nonclinical populations published in Journal of Musical Therapy from 1964 through 2004. Criteria for inclusion were music or music therapy as an independent variable applied to one or more groups and at least one control group that did not receive a music treatment. Control groups were qualified as alternative treatment, placebo, no contact, and treatment as usual. Of the 692 articles, 94 met these criteria, 62 clinical and 32 nonclinical, representing 13.5% of the publications. Results indicated that research with clinical populations involved a mean of 38.1 subjects typically divided into two groups, an experimental and a control group. The pretest-posttest design was the most common (55%) as was a treatment as usual control group (45%). These design methods maximized the impact of the experimental music treatment on outcome. Experimental music groups significantly improved over control groups in the vast majority of studies identified. Undoubtedly, the foundation for evidence-based clinical practice is firm.
Xu, Mengting; Richardson, Lesley; Campbell, Sally; Pintos, Javier; Siemiatycki, Jack
2018-04-09
The purpose of this study was to describe time trends in response rates in case-control studies of cancer and identify study design factors that influence response rate. We reviewed 370 case-control studies of cancer published in 12 journals during indicator years in each of the last four decades. We estimated time trends of response rates and reasons for nonresponse in each of the following types of study subjects: cases, medical source controls, and population controls. We also estimated response rates according to characteristics of study context. Median response rates among cases and population controls were between 75% and 80% in the 1970s. Between 1971 and 2010, study response rates declined by 0.31% per year for cases and 0.78% for population controls. Only a minority of studies reported reasons for nonparticipation; subject refusal was the most common reported reason. Studies conducted in North America had lower median response rates than studies conducted in Europe. In-person and telephone interviews elicited higher response rates than mail questionnaires. Response rates from case-control studies of cancer have declined, and this could threaten the validity of results derived from these studies. Copyright © 2018 Elsevier Inc. All rights reserved.
Dreber, H; Reynisdottir, S; Angelin, B; Tynelius, P; Rasmussen, F; Hemmingsson, E
2017-02-01
Young adults (18-25) with severe obesity constitute a challenging patient group, and there is limited evidence about their mental health status compared to population controls. Mental distress in treatment seeking young adults with severe obesity (n = 121, mean body mass index [BMI] = 39.8 kg m -2 ) was compared with matched (1:3 for age, gender and socioeconomic status) population controls of normal weight (n = 363, mean BMI = 22.4 kg m -2 ), as well as unmatched population controls with class I obesity (n = 105, mean BMI = 32.1 kg m -2 ) or severe obesity (n = 41, mean BMI = 39.7 kg m -2 ). Mental distress was measured by the General Health Questionnaire-12 (GHQ-12), and we quantified physician-diagnosed depression, present anxiety and suicide attempts. Poisson regression and linear regression analysis were used for analysing differences in mental distress between groups. Treatment seekers experienced more mental distress than normal weight controls as measured by continuous (adjusted mean: 3.9 vs. 2.2 points, P <0.001) and categorical (cut-off for mental distress ≥3 points, RR: 1.76, P <0.001) GHQ-12 scores, depression (RR: 2.18, P < 0.001), anxiety (RR: 1.97, P < 0.001) and suicide attempts (RR: 2.04; P = 0.034). Treatment seekers also experienced more mental distress as measured by continuous GHQ-12 than controls with class I obesity (adjusted mean: 2.3 points) or severe obesity (adjusted mean: 2.1; both, P < 0.001). Young adult treatment seekers with severe obesity constitute a risk group for mental distress compared to population controls of different BMI levels. © 2017 World Obesity Federation.
mtDNA sequence diversity of Hazara ethnic group from Pakistan.
Rakha, Allah; Fatima; Peng, Min-Sheng; Adan, Atif; Bi, Rui; Yasmin, Memona; Yao, Yong-Gang
2017-09-01
The present study was undertaken to investigate mitochondrial DNA (mtDNA) control region sequences of Hazaras from Pakistan, so as to generate mtDNA reference database for forensic casework in Pakistan and to analyze phylogenetic relationship of this particular ethnic group with geographically proximal populations. Complete mtDNA control region (nt 16024-576) sequences were generated through Sanger Sequencing for 319 Hazara individuals from Quetta, Baluchistan. The population sample set showed a total of 189 distinct haplotypes, belonging mainly to West Eurasian (51.72%), East & Southeast Asian (29.78%) and South Asian (18.50%) haplogroups. Compared with other populations from Pakistan, the Hazara population had a relatively high haplotype diversity (0.9945) and a lower random match probability (0.0085). The dataset has been incorporated into EMPOP database under accession number EMP00680. The data herein comprises the largest, and likely most thoroughly examined, control region mtDNA dataset from Hazaras of Pakistan. Copyright © 2017 Elsevier B.V. All rights reserved.
Awareness regarding contraception and population control among school going adolescents.
Jahnavi, G; Patra, S R
2009-12-01
Growing sexuality among adolescents increases their risk of getting reproductive tract infections and pregnancy. This Cross sectional survey was done to assess the knowledge and attitude of higher secondary school children regarding contraception and population control. Majority of students (94.4%) were aware of contraceptives and their easy availability on chemist shop. However very few were aware of name and how to use them and 60% of them considered that condom is an emergency contraceptive. Lack of employment facilities as a consequence of uncontrolled population growth was the main concern of both boys and girls. The two children norm was acceptable to most, with one son and one daughter. All perceived that there is need to be informed about contraceptives. Most of the adolescents are misinformed about contraceptives and their attitude is not favorable as far as responsibility is concerned. There is an unmet need of contraceptive & population control knowledge and attitude among school adolescents and require urgent intervention.
Chen, Han; Wang, Chaolong; Conomos, Matthew P.; Stilp, Adrienne M.; Li, Zilin; Sofer, Tamar; Szpiro, Adam A.; Chen, Wei; Brehm, John M.; Celedón, Juan C.; Redline, Susan; Papanicolaou, George J.; Thornton, Timothy A.; Laurie, Cathy C.; Rice, Kenneth; Lin, Xihong
2016-01-01
Linear mixed models (LMMs) are widely used in genome-wide association studies (GWASs) to account for population structure and relatedness, for both continuous and binary traits. Motivated by the failure of LMMs to control type I errors in a GWAS of asthma, a binary trait, we show that LMMs are generally inappropriate for analyzing binary traits when population stratification leads to violation of the LMM’s constant-residual variance assumption. To overcome this problem, we develop a computationally efficient logistic mixed model approach for genome-wide analysis of binary traits, the generalized linear mixed model association test (GMMAT). This approach fits a logistic mixed model once per GWAS and performs score tests under the null hypothesis of no association between a binary trait and individual genetic variants. We show in simulation studies and real data analysis that GMMAT effectively controls for population structure and relatedness when analyzing binary traits in a wide variety of study designs. PMID:27018471
Diniz, Fabio M; Maclean, Norman; Ogawa, Masayoshi; Cintra, Israel H A; Bentzen, Paul
2005-01-01
Atlantic spiny lobsters support major fisheries in northeastern Brazilian waters and in the Caribbean Sea. To avoid reduction in diversity and elimination of distinct stocks, understanding their population dynamics, including structuring of populations and genetic diversity, is critical. We here explore the potential of using the hypervariable domain in the control region of the mitochondrial DNA as a genetic marker to characterize population subdivision in spiny lobsters, using Panulirus argus as the species model. The primers designed on the neighboring conserved genes have amplified the entire control region (approx. 780 bases) of P. argus and other closely related species. Average nucleotide and haplotype diversity within P. argus were found to be high, and population structuring was hypothesized. The data suggest a division of P. argus into genetically different phylogeographic groups. The hypervariable domain seems to be useful for determining genetic differentiation of geographically distinct stocks of P. argus and other Atlantic spiny lobsters.
Monitoring and controlling ovarian activity in elephants.
Thitaram, Chatchote; Brown, Janine L
2018-03-15
Both Asian (Elephas maximus) and African (Loxodonta africana) elephants are important keystone, umbrella and flagship species. Paradoxically, world population numbers of both species are declining in many of their natural ranges due mainly to poaching, while over population of elephants in some areas is resulting in serious human-elephant conflict, and modifications of natural habitats that impact biodiversity. Understanding mechanisms of reproductive control is vital to effective population management, and for that reason significant advances have been made in endocrine and ultrasonographic monitoring techniques, particularly in studies of elephants ex situ. However, there remains a need to develop new methods to control ovarian activity, both for enhancing and inhibiting reproduction, to maintain population numbers at levels that ensure species survival and their ability to safely cohabitate with humans and other species. We present an overview of reproductive monitoring methods and how they have contributed to our knowledge of elephant reproductive biology, as well as their application for in situ and ex situ conservation purposes. Copyright © 2017 Elsevier Inc. All rights reserved.
Echinococcosis: Control and Prevention.
Craig, P S; Hegglin, D; Lightowlers, M W; Torgerson, P R; Wang, Q
2017-01-01
Human cystic echinococcosis (CE) has been eliminated or significantly reduced as a public health problem in several previously highly endemic regions. This has been achieved by the long-term application of prevention and control measures primarily targeted to deworming dogs, health education, meat inspection, and effective surveillance in livestock and human populations. Human CE, however, remains a serious neglected zoonotic disease in many resource-poor pastoral regions. The incidence of human alveolar echinococcosis (AE) has increased in continental Europe and is a major public health problem in parts of Eurasia. Better understanding of wildlife ecology for fox and small mammal hosts has enabled targeted anthelmintic baiting of fox populations and development of spatially explicit models to predict population dynamics for key intermediate host species and human AE risk in endemic landscapes. Challenges that remain for echinococcosis control include effective intervention in resource-poor communities, better availability of surveillance tools, optimal application of livestock vaccination, and management and ecology of dog and wildlife host populations. Copyright © 2017 Elsevier Ltd. All rights reserved.
Fitzpatrick, S; Watts, P C; Feliciangeli, M D; Miles, M A; Kemp, S J
2009-03-01
Rhodnius prolixus is the main vector of Chagas disease in Venezuela, where it is found colonising rural housing consisting of unplastered adobe walls with palm and/or metal roofs. Vector control failure in Venezuela may be due to the invasion of houses by silvatic populations of R. prolixus found in palms. As part of a study to determine if domestic and silvatic populations of R. prolixus are isolated, thus clarifying the role of silvatic populations in maintaining house infestations, we constructed three partial genomic microsatellite libraries. A panel of ten dinucleotide polymorphic microsatellite markers was selected for genotyping. Allele numbers per locus ranged from three to twelve, with observed and expected heterozygosity ranging from 0.26 to 0.55 and 0.32 to 0.66. The microsatellite markers presented here will contribute to the control of Chagas disease in Venezuela and Colombia through the provision of population information that may allow the design of improved control strategies.
Insect management in deciduous orchard ecosystems: Habitat manipulation
NASA Astrophysics Data System (ADS)
Tedders, W. L.
1983-01-01
Current literature pertaining to habitat manipulation of deciduous fruit and nut orchards for pest control is reviewed. The hypothesis of pesticide-induced pest problems in deciduous orchards as well as the changing pest population dynamics of deciduous orchards is discussed An experimental habitat manipulation program for pecans, utilizing vetch cover crops to enhance lady beetle populations for pecan aphid control is presented
Huntington II Simulation Program - RATS. Student Workbook, Teacher's Guide, and Resource Handbook.
ERIC Educational Resources Information Center
Frishman, Austin
Presented are instructions for the use of "RATS," a model simulating the dynamics of a rat population in either a city or an apartment house. The student controls the conditions of growth and sets the points at which the computer program prints reports. The rat population is controlled by variables including garbage levels selected for the site,…
ERIC Educational Resources Information Center
Klesges, Robert C.; DeBon, Margaret; Vander Weg, Mark W.; Haddock, C. Keith; Lando, Harry A.; Relyea, George E.; Peterson, Alan L.; Talcott, G. Wayne
2006-01-01
The authors evaluated the effect of a brief tailored smoking control intervention delivered during basic military training on tobacco use in a population of military personnel (N = 33,215). Participants were randomized to either a tobacco use intervention (smoking cessation, smokeless tobacco use cessation, or prevention depending on tobacco…
Jemec, Anita; Lešer, Vladka; Drobne, Damjana
2012-05-01
The aim of this work was to investigate if the activities of catalase and glutathione S-transferase in a control population of terrestrial isopods (Porcellio scaber) are correlated with the physiological condition of the isopods. For this purpose, the activities of these enzymes were analysed in isopods from a stock population and in parallel, the physiological condition of the same specimens was assessed using a histological approach based on epithelial thickness and lipid droplets. We found a correlation between antioxidant enzymes and the physiological condition of the isopods. This implies that these enzymes could be used as predictive indicators of the physiological condition in a stock population before comprehensive toxicological studies are conducted and also in control group after the experiment. When a control group is found to be very heterogeneous in terms of physiological condition, the experiment should be repeated with a larger number of experimental animals. The findings of this study will contribute to more accurate experimental design of toxicity tests when using biomarkers. This should encourage other researchers to increase their effort to know the physiological state of their test organisms. Copyright © 2011 Elsevier Inc. All rights reserved.
Laine, J; Huovinen, E; Virtanen, M J; Snellman, M; Lumio, J; Ruutu, P; Kujansuu, E; Vuento, R; Pitkänen, T; Miettinen, I; Herrala, J; Lepistö, O; Antonen, J; Helenius, J; Hänninen, M-L; Maunula, L; Mustonen, J; Kuusi, M
2011-07-01
An inappropriate cross-connection between sewage- and drinking-water pipelines contaminated tap water in a Finnish town, resulting in an extensive waterborne gastroenteritis outbreak in this developed country. According to a database and a line-list, altogether 1222 subjects sought medical care as a result of this exposure. Seven pathogens were found in patient samples of those who sought treatment. To establish the true disease burden from this exposure, we undertook a population-based questionnaire investigation with a control population, infrequently used to study waterborne outbreaks. The study covered three areas, contaminated and uncontaminated parts of the town and a control town. An estimated 8453 residents fell ill during the outbreak, the excess number of illnesses being 6501. Attack rates were 53% [95% confidence interval (CI) 49.5-56.4] in the contaminated area, 15.6% (95% CI 13.1-18.5) in the uncontaminated area and 6.5% (95% CI 4.8-8.8) in the control population. Using a control population allowed us to differentiate baseline morbidity from the observed morbidity caused by the water contamination, thus enabling a more accurate estimate of the disease burden of this outbreak.
A study of three polymorphic sites of ADA gene in colon cancer.
Spina, C; Saccucci, P; Cozzoli, E; Bottini, E; Gloria-Bottini, F
2010-12-01
Adenosine inhibits the immune response in tumors. Adenosine deaminase (ADA) controls adenosine level and as ecto-enzyme acts as costimulatory molecule of adenosine receptors and/or CD26. We examined ADA₁, ADA₂, ADA₆ polymorphic sites of ADA gene in 109 subjects with colon cancer from Rome's population and in 246 blood donors as controls from the same population. In colon cancer ADA₁*2/ADA₂*1 haplotype is more represented, while ADA₁*2/ADA₂*2 is less represented than in controls. ADA₂*2/ADA₆*2 is less represented in patients than in controls. Polymorphic sites of ADA might influence cell-mediated anti-tumor immune responses controlling adenosine level and extraenzymatic protein functions.
Scaling of Attitudes Toward Population Problems
ERIC Educational Resources Information Center
Watkins, George A.
1975-01-01
This study related population problem attitudes and socioeconomic variables. Six items concerned with number of children, birth control, family, science, economic depression, and overpopulation were selected for a Guttman scalogram. Education, occupation, and number of children were correlated with population problems scale scores; marital status,…
The construction of a "population problem" in colonial India, 1919-1947.
Nair, Rahul
2011-01-01
This article examines the construction of a "population problem" among public health officials in India during the inter-war period. British colonial officials came to focus on India's population through their concern with high Indian infant and maternal mortality rates. They raised the problem of population as one way in which to highlight the importance of dealing with public health at an all-India basis, in a context of constitutional devolution of power to Indians where they feared such matters would be relegated to relative local unimportance. While they failed to significantly shape government policy, their arguments in support of India's 'population problem' nevertheless found a receptive audience in the colonial public sphere among Indian intellectuals, economists, eugenicists, women social reformers and birth controllers. The article contributes to the history of population control by situating its pre-history in British colonial public health and development policy and outside the logic of USA's Cold War strategic planning for Asia.
Jansen, Mieke; Stoks, Robby; Coors, Anja; van Doorslaer, Wendy; de Meester, Luc
2011-09-01
Although natural populations may evolve resistance to anthropogenic stressors such as pollutants, this evolved resistance may carry costs. Using an experimental evolution approach, we exposed different Daphnia magna populations in outdoor containers to the carbamate pesticide carbaryl and control conditions, and assessed the resulting populations for both their resistance to carbaryl as well as their susceptibility to infection by the widespread bacterial microparasite Pasteuria ramosa. Our results show that carbaryl selection led to rapid evolution of carbaryl resistance with seemingly no cost when assessed in a benign environment. However, carbaryl-resistant populations were more susceptible to parasite infection than control populations. Exposure to both stressors reveals a synergistic effect on sterilization rate by P. ramosa, but this synergism did not evolve under pesticide selection. Assessing costs of rapid adaptive evolution to anthropogenic stress in a semi-natural context may be crucial to avoid too optimistic predictions for the fitness of the evolving populations. © 2011 The Author(s).
Walsh, Matthew C; Trentham-Dietz, Amy; Gangnon, Ronald E; Nieto, F Javier; Newcomb, Polly A; Palta, Mari
2012-06-01
Increasing numbers of individuals are choosing to opt out of population-based sampling frames due to privacy concerns. This is especially a problem in the selection of controls for case-control studies, as the cases often arise from relatively complete population-based registries, whereas control selection requires a sampling frame. If opt out is also related to risk factors, bias can arise. We linked breast cancer cases who reported having a valid driver's license from the 2004-2008 Wisconsin women's health study (N = 2,988) with a master list of licensed drivers from the Wisconsin Department of Transportation (WDOT). This master list excludes Wisconsin drivers that requested their information not be sold by the state. Multivariate-adjusted selection probability ratios (SPR) were calculated to estimate potential bias when using this driver's license sampling frame to select controls. A total of 962 cases (32%) had opted out of the WDOT sampling frame. Cases age <40 (SPR = 0.90), income either unreported (SPR = 0.89) or greater than $50,000 (SPR = 0.94), lower parity (SPR = 0.96 per one-child decrease), and hormone use (SPR = 0.93) were significantly less likely to be covered by the WDOT sampling frame (α = 0.05 level). Our results indicate the potential for selection bias due to differential opt out between various demographic and behavioral subgroups of controls. As selection bias may differ by exposure and study base, the assessment of potential bias needs to be ongoing. SPRs can be used to predict the direction of bias when cases and controls stem from different sampling frames in population-based case-control studies.
Addressing the Social Determinants of Health to Reduce Tobacco-Related Disparities.
Garrett, Bridgette E; Dube, Shanta R; Babb, Stephen; McAfee, Tim
2015-08-01
Comprehensive tobacco prevention and control efforts that include implementing smoke-free air laws, increasing tobacco prices, conducting hard-hitting mass media campaigns, and making evidence-based cessation treatments available are effective in reducing tobacco use in the general population. However, if these interventions are not implemented in an equitable manner, certain population groups may be left out causing or exacerbating disparities in tobacco use. Disparities in tobacco use have, in part, stemmed from inequities in the way tobacco control policies and programs have been adopted and implemented to reach and impact the most vulnerable segments of the population that have the highest rates of smokings (e.g., those with lower education and incomes). Education and income are the 2 main social determinants of health that negatively impact health. However, there are other social determinants of health that must be considered for tobacco control policies to be effective in reducing tobacco-related disparities. This article will provide an overview of how tobacco control policies and programs can address key social determinants of health in order to achieve equity and eliminate disparities in tobacco prevention and control. Tobacco control policy interventions can be effective in addressing the social determinants of health in tobacco prevention and control to achieve equity and eliminate tobacco-related disparities when they are implemented consistently and equitably across all population groups. Taking a social determinants of health approach in tobacco prevention and control will be necessary to achieve equity and eliminate tobacco-related disparities. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Scantlebury, Dawn C; Prasad, Abhiram; Rabinstein, Alejandro A; Best, Patricia J M
2013-05-01
Apical ballooning syndrome (ABS), migraine, and Raynaud phenomenon are characterized by female predominance, identifiable triggers, and, likely, vascular dysfunction. Estrogen deficiency, such as in menopause, is considered to be a predisposing factor for ABS. We investigated the association of ABS with migraine, Raynaud phenomenon, and hormonal factors. We compared 25 consecutive residents (all women) of Olmsted County, Minnesota, presenting with ABS, to 2 age-matched control groups from the same community: 25 women presenting with ST-segment elevation myocardial infarction (STEMI), matched for the index ABS event date, and 50 women with neither diagnosis. The patients with ABS were more likely to have a migraine history (11 [44%] vs 4 [16%] STEMI controls, p = 0.031, and vs 6 [12%] population controls, p = 0.003), and "possible migraine" (including other headache syndromes suggestive of migraine; 15 [60%] vs 6 [24%] STEMI controls, p = 0.012; and vs 12 [24%] population controls, p = 0.003). Of the patients with ABS, 4 (16%) had Raynaud phenomenon compared to no STEMI controls and 1 (2%) population control (p = 0.038). No differences were present in parity, menopausal status, years since the onset of menopause, and frequency of oophorectomy. Current hormonal replacement therapy use was greater in those with ABS than in the population controls: 4 (16%) versus none (p = 0.002). In conclusion, the association of ABS with migraine and Raynaud phenomenon supports a role of vasomotor dysfunction in the pathogenesis of ABS. The absence of an association with reproductive characteristics and the finding that ABS occurred despite exogenous hormonal use in some patients suggests that estrogen deficiency per se is not the primary factor in the pathophysiology. Copyright © 2013 Elsevier Inc. All rights reserved.
Attitudes towards helminthic infection in the Jirel population of eastern Nepal.
Williams-Blangero, S; Subedi, J; Upadhayay, R P; Manral, D B; Khadka, K; Jirel, S; Robinson, E S; Blangero, J
1998-08-01
Intestinal worm infections, including roundworm, hookworm, and whipworm, are major international health concerns, affecting approximately one fourth of the world's population. Many intervention schemes have been attempted to control these infections in heavily exposed populations, but success has been limited because individuals are readily reinfected upon renewed exposure. Few data are available concerning people's health beliefs about soil-transmitted helminthic infections in such populations. The purpose of this study was to assess health beliefs about common helminthiasis in a population experiencing moderate to high rates of infection. The focal population for the study was the Jirel population, a tribal group distributed across nine villages in the Jiri Region of Dolakha District, eastern Nepal. The results indicate that beliefs about the types, causes, and treatments of helminthic infections have been developed and reinforced by experience and empirical evidence. People's frequent inability to confirm the efficacy of drug therapy by observing worms in stools has led to dissatisfaction with biomedical approaches. Carefully planned education programs are required to alter prevailing attitudes and improve control of soil-transmitted helminthiasis in the region.
The effect of shovel trait on Carabelli's trait in Taiwan Chinese and Aboriginal populations.
Hsu, J W; Tsai, P L; Hsiao, T H; Chang, H P; Lin, L M; Liu, K M; Yu, H S; Ferguson, D
1997-09-01
Chinese and other Mongoloid populations differ from Caucasoids by having a high prevalence of shovel trait and a low prevalence of Carabelli's trait. This study was conducted to compare the association between the shovel and the Carabelli's traits between Chinese and aboriginal Mongoloid populations. The research is designed to sample randomly a Chinese population and an aboriginal population having low admixture with neighboring populations. The Mongoloid aboriginal group was from the Bunun tribe who resides in an isolated alpine area in Taiwan. The effects of sex and age on Carabelli's trait were controlled in this study, as was the association between tooth size and Carabelli's trait. Our results show that males had more Carabelli's trait expressed on teeth than females in both of these two Mongoloid populations. The buccolingual diameter of Carabelli's trait teeth was larger than that of teeth without the trait. After controlling for sex, age, and tooth size, the existence of the shovel trait significantly increased the likelihood of having Carabelli's trait, especially in Chinese, which implies another significant ethnic feature for Mongoloid identification.
Platou, Toril Forbord; Skjeldestad, Finn Egil; Rannestad, Toril
2010-03-01
The population of gynaecological cancer survivors is growing, yet little is known about the effects of cancer and treatment on socioeconomic conditions well beyond the completion of therapy. The aim of this study was to investigate the socioeconomic conditions in long-term survivors of gynaecological cancer compared with a representative group of women from the general population. The study comprises women aged 32-75 residing in central part of Norway and who were treated as primary cases of gynaecological cancer at the University Hospital in Trondheim, Norway (n=160), and a control group from the general population (n=493). All analyses were done by chi(2) test and logistic regression. Gynaecological cancer survivors scored lower on a Socioeconomic Condition Index than the control group. They had on the average a complete remission period of 12 years. Compared with the control group, they were more often disabled (p<0.01) and had lower annual household income (p<0.01). No difference was detected between the groups in ability to pay bills. More cases than controls had experienced problems assigning personal insurance (p<0.03). Long-term gynaecological cancer survivors lived under poorer socioeconomic conditions, were more often disabled and had lower annual household income than the women in the control group, whereas no difference in ability to pay bills were found between the groups. In spite of poorer socioeconomic conditions, the gynaecological cancer survivors seem to adapt well to their financial situation.
Park, Ji Soo; Nam, Eun Ji; Park, Hyung Seok; Han, Jung Woo; Lee, Jung-Yun; Kim, Jieun; Kim, Tae Il; Lee, Seung-Tae
2017-10-01
Comparison of variant frequencies in the general population has become an essential part of the American College of Medical Genetics and Genomics (ACMG) standards and guidelines for interpreting sequence variants. We determined the optimal number of relevant ethnic controls that should be used to accurately calculate the odds ratio (OR) of genetic variants. Using the ACMG guidelines, we reclassified BRCA1 and BRCA2 mutations and variants of unknown significance in 745 Korean patients susceptible to hereditary breast and ovarian cancer compared with 1,314 Korean population controls. We observed that the ORs were falsely inflated when we analyzed several variants using non-Korean population data. Our simulation indicated that the number of controls needed for the lower limit of a 95% confidence interval to exceed 1.0 varied according to the frequency of the variant in each patient group, with more than 820 controls needed for a variant existing in 1% of cases. Using a sufficient number of relevant population data, we could efficiently classify variants and identified the BRCA1 p.Leu1780Pro mutation as a possible pathogenic founder mutation in Korean patients. Our study suggests that BRCA1 p.Leu1780Pro is a novel pathogenic mutation found in Korean patients. We also determined the optimal number of relevant ethnic controls needed for accurate variant classification according to the ACMG guidelines.
Genetic control of invasive plants species using selfish genetic elements
Hodgins, Kathryn A; Rieseberg, Loren; Otto, Sarah P
2009-01-01
Invasive plants cause substantial environmental damage and economic loss. Here, we explore the possibility that a selfish genetic element found in plants called cytoplasmic male sterility (CMS) could be exploited for weed control. CMS is caused by mutations in the mitochondrial genome that sterilize male reproductive organs. We developed an analytical model and a spatial simulation to assess the use of CMS alleles to manage weed populations. Specifically, we examined how fertility, selfing, pollen limitation and dispersal influenced extinction rate and time until extinction in populations where CMS arises. We found that the introduction of a CMS allele can cause rapid population extinction, but only under a restricted set of conditions. Both models suggest that the CMS strategy will be appropriate for species where pollen limitation is negligible, inbreeding depression is high and the fertility advantage of females over hermaphrodites is substantial. In general, spatial structure did not have a strong influence on the simulation outcome, although low pollen dispersal and intermediate levels of seed dispersal tended to reduce population extinction rates. Given these results, the introduction of CMS alleles into a population of invasive plants probably represents an effective control method for only a select number of species. PMID:25567898
Small mammal populations in Maryland meadows during four years of herbicide (brominal®) applications
Clark, D.R.; Moulton, C.A.; Hines, J.E.; Hoffman, D.J.
1996-01-01
The herbicide Brominal® was applied at the recommended rate to one plot in each of three paired 0.6-ha plots; the other three plots were used as controls. Plots were sprayed once in the fall of 1988 and 1989 and twice in the spring of 1990 and 1991. Small mammals were trapped three times during each activity season (April-October) to obtain population estimates before and after spraying and in the spring preceding fall spraying or the fall following spring spraying. Population estimates immediately after spraying gave no evidence of direct mortality. By 1991, dicot vegetation on treated plots was suppressed and mean numbers of meadow voles (Microtus pennsylvanicus) were less than on control plots. Because meadow voles favor dicots over monocots in their diet, reduced availability of dicots may have been related to the smaller vole population estimates. Species diversity of small mammals was negatively correlated with size of vole populations, but was not different between treated and control plots. Brominal apparently induced opaque corneas in nine voles. The condition was found in two voles too small to have been conceived at the time of the last previous spray nearly 8 months earlier, suggesting exposure to residue alone.
Toxicity of non-pyrethroid insecticides against Triatoma infestans (Hemiptera: Reduviidae).
Carvajal, Guillermo; Mougabure-Cueto, Gastón; Toloza, Ariel Ceferino
2012-08-01
Triatoma infestans (Klug) is the main vector of Chagas disease, which is a public health concern in most Latin American countries. The prevention of Chagas disease is based on the chemical control of the vector using pyrethroid insecticides. In the last decade, different levels of deltamethrin resistance have been detected in certain areas of Argentina and Bolivia. Because of this, alternative non-pyrethroid insecticides from different chemical groups were evaluated against two T. infestans populations, NFS and El Malá, with the objective of finding new insecticides to control resistant insect populations. Toxicity to different insecticides was evaluated in a deltamethrin-susceptible and a deltamethrin-resistant population. Topical application of the insecticides fenitrothion and imidacloprid to first nymphs had lethal effects on both populations, producing 50% lethal dose (LD50) values that ranged from 5.2-28 ng/insect. However, amitraz, flubendiamide, ivermectin, indoxacarb and spinosad showed no insecticidal activity in first instars at the applied doses (LD50 > 200 ng/insect). Fenitrothion and imidacloprid were effective against both deltamethrin-susceptible and deltamethrin-resistant populations of T. infestans. Therefore, they may be considered alternative non-pyrethroid insecticides for the control of Chagas disease.
Conde, Marcela; Orjuela, Lorena I; Castellanos, César Augusto; Herrera-Varela, Manuela; Licastro, Susana; Quiñones, Martha L
2015-01-01
Continuous use of insecticides for the control of dengue transmission may lead to decreased susceptibility levels in mosquito vector populations. Timely monitoring is necessary to ensure detection of any potential resistance problems. To determine the susceptibility status of Aedes aegypti to insecticides used in public health in Caldas, Colombia, during 2007 and 2011. Susceptibility tests to the organophosphates temephos, malathion, fenitrothion and pirimiphos methyl, as well as to the pyrethroid deltamethrin, were carried out using standard World Health Organization and Centers for Disease Control and Prevention protocols. In 2007, resistance to temephos was detected in Ae. aegypti populations from La Dorada with resistance ratios of 11.5 and 13.3, prompting the Caldas Health Department to suspend the use of this larvicide. A reduction in resistance ratios to temephos was observed in 2011, as well as an apparent resistance to pirimiphos methyl. All Ae. aegypti populations tested were susceptible to deltamethrin, malathion and fenitrothion in both years. Evaluating the resistance ratios during two distinct periods allowed a decrease in resistance to be detected after suspension of the use of temephos. Surveillance of mosquito populations for changes in susceptibility levels to the insecticides used in dengue control programs is therefore recommended.
NASA Astrophysics Data System (ADS)
Kurniawan, Dian; Suparti; Sugito
2018-05-01
Population growth in Indonesia has increased every year. According to the population census conducted by the Central Bureau of Statistics (BPS) in 2010, the population of Indonesia has reached 237.6 million people. Therefore, to control the population growth rate, the government hold Family Planning or Keluarga Berencana (KB) program for couples of childbearing age. The purpose of this program is to improve the health of mothers and children in order to manifest prosperous society by controlling births while ensuring control of population growth. The data used in this study is the updated family data of Semarang city in 2016 that conducted by National Family Planning Coordinating Board (BKKBN). From these data, classifiers with kernel discriminant analysis will be obtained, and also classification accuracy will be obtained from that method. The result of the analysis showed that normal kernel discriminant analysis gives 71.05 % classification accuracy with 28.95 % classification error. Whereas triweight kernel discriminant analysis gives 73.68 % classification accuracy with 26.32 % classification error. Using triweight kernel discriminant for data preprocessing of family planning participation of childbearing age couples in Semarang City of 2016 can be stated better than with normal kernel discriminant.
Genetic Control of Contagious Asexuality in the Pea Aphid
Jaquiéry, Julie; Stoeckel, Solenn; Larose, Chloé; Nouhaud, Pierre; Rispe, Claude; Mieuzet, Lucie; Bonhomme, Joël; Mahéo, Frédérique; Legeai, Fabrice; Gauthier, Jean-Pierre; Prunier-Leterme, Nathalie; Tagu, Denis; Simon, Jean-Christophe
2014-01-01
Although evolutionary transitions from sexual to asexual reproduction are frequent in eukaryotes, the genetic bases of such shifts toward asexuality remain largely unknown. We addressed this issue in an aphid species where both sexual and obligate asexual lineages coexist in natural populations. These sexual and asexual lineages may occasionally interbreed because some asexual lineages maintain a residual production of males potentially able to mate with the females produced by sexual lineages. Hence, this species is an ideal model to study the genetic basis of the loss of sexual reproduction with quantitative genetic and population genomic approaches. Our analysis of the co-segregation of ∼300 molecular markers and reproductive phenotype in experimental crosses pinpointed an X-linked region controlling obligate asexuality, this state of character being recessive. A population genetic analysis (>400-marker genome scan) on wild sexual and asexual genotypes from geographically distant populations under divergent selection for reproductive strategies detected a strong signature of divergent selection in the genomic region identified by the experimental crosses. These population genetic data confirm the implication of the candidate region in the control of reproductive mode in wild populations originating from 700 km apart. Patterns of genetic differentiation along chromosomes suggest bidirectional gene flow between populations with distinct reproductive modes, supporting contagious asexuality as a prevailing route to permanent parthenogenesis in pea aphids. This genetic system provides new insights into the mechanisms of coexistence of sexual and asexual aphid lineages. PMID:25473828
ERIC Educational Resources Information Center
United Nations Educational, Scientific and Cultural Organization, Bangkok (Thailand). Principal Regional Office for Asia and the Pacific.
This manual is the result of a regional training workshop on the cost-effectiveness of different training strategies in population education by Unesco in Kathmandu, Nepal, June 1-8, 1987. The purpose of the manual is to enable project staff to initiate studies to determine cost-effective training strategies in population growth control education.…
Carter, Marissa J; Fife, Caroline E; Walker, David; Thomson, Brett
2009-07-01
To determine the percentage of individuals that would be excluded from wound care randomized controlled trials (RCTs) as a surrogate for applicability to general populations. A representative sample of wound-care RCTs was selected from the literature in the past 10 years. Exclusion criteria from the trials were evaluated, and prevalence values for each excluded condition were obtained from a large wound-care population, as well as from the literature. The percentage of patients excluded on this basis was calculated. Seventeen RCTs testing "high-technology" wound-care products were evaluated. : Patients in the trials were treated for ulcers (venous, diabetic foot, and pressure ulcers). A percentage of patients in the study population were excluded for each RCT. More than 50% of the study population would have been excluded in 15 of the 17 RCTs. When less clinically relevant exclusion criteria were removed, 14 of 17 RCTs would still have excluded between 25% and 50% of the study population. The results raise serious questions regarding the applicability of these RCTs to wound-care populations.
Iarushin, S V
2007-01-01
The paper describes a principal scheme of insurance protection organization due to the negative human influences of environmental factors and industrial risks as one of the most effective mechanisms responsible for controlling sanitary-and-epidemiological well-being and human health. It also considers how a voluntary medical collective insurance program and a civil responsibility insurance one are being implemented due to unforeseen damages done to the population's health and how the quality and safety of goods (work, services) are controlled. Organizational, methodic, and normative legal approaches are proposed to developing the population's insurance protection system.
Higashi, Hideki; Khuong, Tuan A; Ngo, Anh D; Hill, Peter S
2011-07-01
Population-based health promotion and disease prevention approaches are essential elements in achieving universal health coverage; yet they frequently do not appear on national policy agendas. This paper suggests that resource-poor countries should take greater advantage of such approaches to reach all segments of the population to positively affect health outcomes and equity, especially considering the epidemic of chronic non-communicable diseases and associated modifiable risk factors. Tobacco control policy development and implementation in Vietnam provides a case study to discuss opportunities and challenges associated with such strategies.
ISFM guidelines on population management and welfare of unowned domestic cats (Felis catus).
Sparkes, Andrew H; Bessant, Claire; Cope, Kevin; Ellis, Sarah L H; Finka, Lauren; Halls, Vicky; Hiestand, Karen; Horsford, Kim; Laurence, Christopher; MacFarlaine, Ian; Neville, Peter F; Stavisky, Jenny; Yeates, James
2013-09-01
GUIDELINES RATIONALE: Cats are among the most commonly kept domestic pets, and coexist with humans in a variety of different circumstances. Cats are sentient beings and, as such, humans have a responsibility for cat welfare where humans and cats coexist. Because cats reproduce efficiently, measures to control populations are frequently needed, but these should be based on ethical and humane approaches. These consensus guidelines from the International Society of Feline Medicine's Welfare Advisory Panel provide a framework for the approach to welfare and population control measures, primarily among unowned cats and those going through a homing programme.
1986-05-30
insecticide resistance, pheromones 3 A 817 R4A(1 (,CctinL’e on reverse if nece’ssary and idenity by block number) !’,--arch supported by this Contract .as...reproductive state. The results left 1 !7e doubt that females play a leading role in regulating population behavior. Subsequent research on pheromones showed...aggregation pheromone and a less well known dispersal pheromone revealed differences in response with age/sex class Ta the aggregation experiments
Annual report for 2004 wild horse research and field activities
Ransom, Jason; Singer, Francis J.; Zeigenfuss, Linda; Coates-Markle, Linda
2005-01-01
The Bureau of Land Management (BLM) and U.S. Geological Survey-Biological Resources Discipline (USGS/BRD) continued wild horse research in 2004, investigating the strategic research elements of fertility control and population estimation. Fertility control research was focused on the individual-based porcine zonae pellucid (PZP) field trials at the Pryor Mountain Wild Horse Range (WHR), Little Rock Cliffs WHR, and McCullough Peaks Wild Horse Management Area (WHMA). Aerial population estimation research was conducted on a number of western wild horse herds to test different survey techniques as applied to various habitat types and population sizes.
Jurek, Anne M; Maldonado, George; Greenland, Sander
2013-03-01
Special care must be taken when adjusting for outcome misclassification in case-control data. Basic adjustment formulas using either sensitivity and specificity or predictive values (as with external validation data) do not account for the fact that controls are sampled from a much larger pool of potential controls. A parallel problem arises in surveys and cohort studies in which participation or loss is outcome related. We review this problem and provide simple methods to adjust for outcome misclassification in case-control studies, and illustrate the methods in a case-control birth certificate study of cleft lip/palate and maternal cigarette smoking during pregnancy. Adjustment formulas for outcome misclassification that ignore case-control sampling can yield severely biased results. In the data we examined, the magnitude of error caused by not accounting for sampling is small when population sensitivity and specificity are high, but increases as (1) population sensitivity decreases, (2) population specificity decreases, and (3) the magnitude of the differentiality increases. Failing to account for case-control sampling can result in an odds ratio adjusted for outcome misclassification that is either too high or too low. One needs to account for outcome-related selection (such as case-control sampling) when adjusting for outcome misclassification using external information. Copyright © 2013 Elsevier Inc. All rights reserved.
Terry, Paul E; Fowles, Jinnet Briggs; Xi, Min; Harvey, Lisa
2011-01-01
PURPOSE. This study compares a traditional worksite-based health promotion program with an activated consumer program and a control program DESIGN. Group randomized controlled trial with 18-month intervention. SETTING. Two large Midwestern companies. SUBJECTS. Three hundred and twenty employees (51% response). INTERVENTION. The traditional health promotion intervention offered population-level campaigns on physical activity, nutrition, and stress management. The activated consumer intervention included population-level campaigns for evaluating health information, choosing a health benefits plan, and understanding the risks of not taking medications as prescribed. The personal development intervention (control group) offered information on hobbies. The interventions also offered individual-level coaching for high risk individuals in both active intervention groups. MEASURES. Health risk status, general health status, consumer activation, productivity, and the ability to evaluate health information. ANALYSIS. Multivariate analyses controlled for baseline differences among the study groups. RESULTS. At the population level, compared with baseline performance, the traditional health promotion intervention improved health risk status, consumer activation, and the ability to recognize reliable health websites. Compared with baseline performance, the activated consumer intervention improved consumer activation, productivity, and the ability to recognize reliable health websites. At the population level, however, only the activated consumer intervention improved any outcome more than the control group did; that outcome was consumer activation. At the individual level for high risk individuals, both traditional health coaching and activated consumer coaching positively affected health risk status and consumer activation. In addition, both coaching interventions improved participant ability to recognize a reliable health website. Consumer activation coaching also significantly improved self-reported productivity. CONCLUSION. An effective intervention can change employee health risk status and activation both at the population level and at the individual high risk level. However, program engagement at the population level was low, indicating that additional promotional strategies, such as greater use of incentives, need to be examined. Less intensive coaching can be as effective as more intensive, albeit both interventions produced modest behavior change and retention in the consumer activation arm was most difficult. Further research is needed concerning recruitment and retention methods that will enable populations to realize the full potential of activated consumerism.
34 CFR 364.32 - What are the requirements for outreach?
Code of Federal Regulations, 2014 CFR
2014-07-01
... outreach to populations in the State that are unserved or underserved by programs under title VII, including minority groups and urban and rural populations. (b) The State plan must identify the populations... control number 1820-0527) (Authority: 29 U.S.C. 796c(l)) ...
34 CFR 364.32 - What are the requirements for outreach?
Code of Federal Regulations, 2013 CFR
2013-07-01
... outreach to populations in the State that are unserved or underserved by programs under title VII, including minority groups and urban and rural populations. (b) The State plan must identify the populations... control number 1820-0527) (Authority: 29 U.S.C. 796c(l)) ...
34 CFR 364.32 - What are the requirements for outreach?
Code of Federal Regulations, 2012 CFR
2012-07-01
... outreach to populations in the State that are unserved or underserved by programs under title VII, including minority groups and urban and rural populations. (b) The State plan must identify the populations... control number 1820-0527) (Authority: 29 U.S.C. 796c(l)) ...
Organization of population-based cancer control programs: Europe and the world.
Otter, Renée; Qiao, You-Lin; Burton, Robert; Samiei, Massoud; Parkin, Max; Trapido, Edward; Weller, David; Magrath, Ian; Sutcliffe, Simon
2009-01-01
As cancer is to a large extent avoidable and treatable, a cancer control program should be able to reduce mortality and morbidity and improve the quality of life of cancer patients and their families. However, the extent to which the goals of a cancer control program can be achieved will depend on the resource constraints a country faces. Such population-based cancer control plans should prioritize effective interventions and programs that are beneficial to the largest part of the population, and should include activities devoted to prevention, screening and early detection, treatment, palliation and end-of-life care, and rehabilitation. In order to develop a successful cancer control program, leadership and the relevant stakeholders, including patient organizations, need to be identified early on in the process so that all partners can take ownership and responsibility for the program. Various tools have been developed to aid them in the planning and implementation process. However, countries developing a national cancer control program would benefit from a discussion of different models for planning and delivery of population-based cancer control in settings with differing levels of resource commitment, in order to determine how best to proceed given their current level of commitment, political engagement and resources. As the priority assigned to different components of cancer control will differ depending on available resources and the burden and pattern of cancer, it is important to consider the relative roles of prevention, early detection, diagnosis, treatment, rehabilitation and palliative care in a cancer control program, as well as how to align available resources to meet prioritized needs. Experiences from countries with differing levels of resources are presented and serve to illustrate the difficulties in developing and implementing cancer control programs, as well as the innovative strategies that are being used to maximize available resources and enhance the quality of care provided to cancer patients around the world.
Nassir, Rami; Kosoy, Roman; Tian, Chao; White, Phoebe A; Butler, Lesley M; Silva, Gabriel; Kittles, Rick; Alarcon-Riquelme, Marta E; Gregersen, Peter K; Belmont, John W; De La Vega, Francisco M; Seldin, Michael F
2009-01-01
Background Case-control genetic studies of complex human diseases can be confounded by population stratification. This issue can be addressed using panels of ancestry informative markers (AIMs) that can provide substantial population substructure information. Previously, we described a panel of 128 SNP AIMs that were designed as a tool for ascertaining the origins of subjects from Europe, Sub-Saharan Africa, Americas, and East Asia. Results In this study, genotypes from Human Genome Diversity Panel populations were used to further evaluate a 93 SNP AIM panel, a subset of the 128 AIMS set, for distinguishing continental origins. Using both model-based and relatively model-independent methods, we here confirm the ability of this AIM set to distinguish diverse population groups that were not previously evaluated. This study included multiple population groups from Oceana, South Asia, East Asia, Sub-Saharan Africa, North and South America, and Europe. In addition, the 93 AIM set provides population substructure information that can, for example, distinguish Arab and Ashkenazi from Northern European population groups and Pygmy from other Sub-Saharan African population groups. Conclusion These data provide additional support for using the 93 AIM set to efficiently identify continental subject groups for genetic studies, to identify study population outliers, and to control for admixture in association studies. PMID:19630973
Sul, Jae Hoon; Bilow, Michael; Yang, Wen-Yun; Kostem, Emrah; Furlotte, Nick; He, Dan; Eskin, Eleazar
2016-03-01
Although genome-wide association studies (GWASs) have discovered numerous novel genetic variants associated with many complex traits and diseases, those genetic variants typically explain only a small fraction of phenotypic variance. Factors that account for phenotypic variance include environmental factors and gene-by-environment interactions (GEIs). Recently, several studies have conducted genome-wide gene-by-environment association analyses and demonstrated important roles of GEIs in complex traits. One of the main challenges in these association studies is to control effects of population structure that may cause spurious associations. Many studies have analyzed how population structure influences statistics of genetic variants and developed several statistical approaches to correct for population structure. However, the impact of population structure on GEI statistics in GWASs has not been extensively studied and nor have there been methods designed to correct for population structure on GEI statistics. In this paper, we show both analytically and empirically that population structure may cause spurious GEIs and use both simulation and two GWAS datasets to support our finding. We propose a statistical approach based on mixed models to account for population structure on GEI statistics. We find that our approach effectively controls population structure on statistics for GEIs as well as for genetic variants.
Multiple-Herbicide Resistance Is Widespread in Roadside Palmer Amaranth Populations.
Bagavathiannan, Muthukumar V; Norsworthy, Jason K
2016-01-01
Herbicide-resistant Palmer amaranth is a widespread issue in row-crop production in the Midsouthern US. Palmer amaranth is commonly found on roadside habitats in this region, but little is known on the degree of herbicide resistance in these populations. Herbicide resistance in roadside Palmer amaranth populations can represent the spread of an adaptive trait across a selective landscape. A large-scale survey was carried out in the Mississippi Delta region of eastern Arkansas to document the level of resistance in roadside Palmer amaranth populations to pyrithiobac and glyphosate, two important herbicides with broad history of use in the region. A total of 215 Palmer amaranth populations collected across 500 random survey sites were used in the evaluations. About 89 and 73% of the surveyed populations showed >90% survival to pyrithiobac and glyphosate, respectively. Further, only 3% of the populations were completely susceptible to glyphosate, while none of the populations was completely controlled by pyrithiobac. Among the 215 populations evaluated, 209 populations showed multiple resistance to both pyrithiobac and glyphosate at varying degrees. Dose-response assays confirmed the presence of high levels of herbicide resistance in the five selected populations (≥ 25-fold compared to a susceptible standard). Results demonstrate the prevalence of multiple-herbicide resistance in roadside Palmer amaranth populations in this region. Growers should be vigilant of Palmer amaranth infestation in roadsides adjacent to their fields and implement appropriate control measures to prevent likely spread of herbicide resistance into their fields.
Population-Level Cost-Effectiveness of Implementing Evidence-Based Practices into Routine Care
Fortney, John C; Pyne, Jeffrey M; Burgess, James F
2014-01-01
Objective The objective of this research was to apply a new methodology (population-level cost-effectiveness analysis) to determine the value of implementing an evidence-based practice in routine care. Data Sources/Study Setting Data are from sequentially conducted studies: a randomized controlled trial and an implementation trial of collaborative care for depression. Both trials were conducted in the same practice setting and population (primary care patients prescribed antidepressants). Study Design The study combined results from a randomized controlled trial and a pre-post-quasi-experimental implementation trial. Data Collection/Extraction Methods The randomized controlled trial collected quality-adjusted life years (QALYs) from survey and medication possession ratios (MPRs) from administrative data. The implementation trial collected MPRs and intervention costs from administrative data and implementation costs from survey. Principal Findings In the randomized controlled trial, MPRs were significantly correlated with QALYs (p = .03). In the implementation trial, patients at implementation sites had significantly higher MPRs (p = .01) than patients at control sites, and by extrapolation higher QALYs (0.00188). Total costs (implementation, intervention) were nonsignificantly higher ($63.76) at implementation sites. The incremental population-level cost-effectiveness ratio was $33,905.92/QALY (bootstrap interquartile range −$45,343.10/QALY to $99,260.90/QALY). Conclusions The methodology was feasible to operationalize and gave reasonable estimates of implementation value. PMID:25328029
JAAKKOLA, M S; LAITINEN, S; PIIPARI, R; UITTI, J; NORDMAN, H; HAAPALA, A-M; JAAKKOLA, J J K
2002-01-01
Immunoglobulin G (IgG) antibodies against microbes related to indoor dampness problems have been used as potential biomarkers of fungal exposure in clinical investigations. There is limited information on their relation to asthma. We conducted a population-based incident case–control study to assess the risk of asthma in relation to specific IgG antibodies to eight dampness-related microbes: Aspergillus fumigatus, A. versicolor, Cladosporium cladosporioides, Fusarium oxysporum, Sporobolomyces salmonicolor, Stachybotrys chartarum, Streptomyces albus and Trichoderma citrinoviride. We recruited systematically all new cases of asthma during a 2·5-year study period and randomly selected controls from a source population of adults 21–63 years of age living in the Pirkanmaa Hospital District, South Finland. The clinically diagnosed case series consisted of 521 adults with newly diagnosed asthma and the control series of 932 controls selected randomly from the source population. IgG antibodies were analysed with ELISA. An increased risk of developing asthma in adulthood was significantly related to IgG antibodies to T. citrinoviride, but not to the other moulds. There was no evidence of a dose–response relation between the IgG antibody level and the risk of asthma. T. citrinoviride may play a role in the aetiology of adult-onset asthma or serve as an indicator of other causal factors. PMID:12100029
Hansen, Michael J.; Madenjian, Charles P.; Slade, Jeffrey W.; Steeves, Todd B.; Almeida, Pedro R.; Quintella, Bernardo R.
2016-01-01
The sea lamprey Petromyzon marinus (Linnaeus) is both an invasive non-native species in the Laurentian Great Lakes of North America and an imperiled species in much of its native range in North America and Europe. To compare and contrast how understanding of population ecology is useful for control programs in the Great Lakes and restoration programs in Europe, we review current understanding of the population ecology of the sea lamprey in its native and introduced range. Some attributes of sea lamprey population ecology are particularly useful for both control programs in the Great Lakes and restoration programs in the native range. First, traps within fish ladders are beneficial for removing sea lampreys in Great Lakes streams and passing sea lampreys in the native range. Second, attractants and repellants are suitable for luring sea lampreys into traps for control in the Great Lakes and guiding sea lamprey passage for conservation in the native range. Third, assessment methods used for targeting sea lamprey control in the Great Lakes are useful for targeting habitat protection in the native range. Last, assessment methods used to quantify numbers of all life stages of sea lampreys would be appropriate for measuring success of control in the Great Lakes and success of conservation in the native range.
Raiho, Ann M.; Hooten, Mevin B.; Bates, Scott; Hobbs, N. Thompson
2015-01-01
Overabundant populations of ungulates have caused environmental degradation and loss of biological diversity in ecosystems throughout the world. Culling or regulated harvest is often used to control overabundant species. These methods are difficult to implement in national parks, other types of conservation reserves, or in residential areas where public hunting may be forbidden by policy. As a result, fertility control has been recommended as a non-lethal alternative for regulating ungulate populations. We evaluate this alternative using white-tailed deer in national parks in the vicinity of Washington, D.C., USA as a model system. Managers seek to reduce densities of white-tailed deer from the current average (50 deer per km2) to decrease harm to native plant communities caused by deer. We present a Bayesian hierarchical model using 13 years of population estimates from 8 national parks in the National Capital Region Network. We offer a novel way to evaluate management actions relative to goals using short term forecasts. Our approach confirms past analyses that fertility control is incapable of rapidly reducing deer abundance. Fertility control can be combined with culling to maintain a population below carrying capacity with a high probability of success. This gives managers confronted with problematic overabundance a framework for implementing management actions with a realistic assessment of uncertainty.
Raiho, Ann M; Hooten, Mevin B; Bates, Scott; Hobbs, N Thompson
2015-01-01
Overabundant populations of ungulates have caused environmental degradation and loss of biological diversity in ecosystems throughout the world. Culling or regulated harvest is often used to control overabundant species. These methods are difficult to implement in national parks, other types of conservation reserves, or in residential areas where public hunting may be forbidden by policy. As a result, fertility control has been recommended as a non-lethal alternative for regulating ungulate populations. We evaluate this alternative using white-tailed deer in national parks in the vicinity of Washington, D.C., USA as a model system. Managers seek to reduce densities of white-tailed deer from the current average (50 deer per km2) to decrease harm to native plant communities caused by deer. We present a Bayesian hierarchical model using 13 years of population estimates from 8 national parks in the National Capital Region Network. We offer a novel way to evaluate management actions relative to goals using short term forecasts. Our approach confirms past analyses that fertility control is incapable of rapidly reducing deer abundance. Fertility control can be combined with culling to maintain a population below carrying capacity with a high probability of success. This gives managers confronted with problematic overabundance a framework for implementing management actions with a realistic assessment of uncertainty.
Atun, Rifat A; Lebcir, Reda; Drobniewski, Francis; Coker, Richard J
2005-08-01
This study sought to determine the impact of an effective programme of multidrug resistant tuberculosis control (MDRTB) on a population that is witnessing an explosive HIV epidemic among injecting drug users (IDUs), where the prevalence of MDRTB is already high. A transmission model was constructed that represents the dynamics of the drug-susceptible tuberculosis (DSTB), MDRTB and HIV spread among the adult population of Samara Oblast, Russia: from official notifications of tuberculosis and of HIV infection, estimates of MDRTB derived from surveillance studies, population data from official regional statistics, data on transmission probabilities from peer-reviewed publications and informed estimates, and policy-makers' estimates of IDU populations. Two scenarios of programme effectiveness for MDRTB were modelled and run over a period of 10 years to predict cumulative deaths. In a population of 3.3 million with a high prevalence of MDRTB, an emerging epidemic of HIV among IDUs, and a functioning directly observed therapy-short course (DOTS) programme, the model predicts that under low cure rates for MDRTB the expected cumulative deaths from tuberculosis will reach 6303 deaths including 1900 deaths from MDRTB at 10 years. Under high cure rate for MDRTB 4465 deaths will occur including 134 deaths from MDRTB. At 10 years there is little impact on HIV-infected populations from the MDRTB epidemic, but as the HIV epidemic matures the impact becomes substantial. When the model is extended to 20 years cumulative deaths from MDRTB become very high if cure rates for MDRTB are low and cumulative deaths in the HIV-infected population, likewise, are profoundly affected. In the presence of an immature HIV epidemic failure to actively control MDRTB may result in approximately a third more deaths than if effective treatment is given. As the HIV epidemic matures then the impact of MDRTB grows substantially if MDRTB control strategies are ineffective. The epidemiological starting point for these scenarios is present in many regions within the former Soviet Union and this analysis suggests control of MDRTB should be an urgent priority.
Survival of Ranunculus repens L. (creeping buttercup) in an amphibious habitat.
Lynn, D E; Waldren, S
2003-01-01
The turlough form of Ranunculus repens is subjected to several months' complete inundation with hard groundwater. Experimental flooding to the level of the soil surface had no effect on turlough or ruderal populations relative to drained controls. Experimental submergence resulted in direct tissue death of the ruderal population but did not affect the turlough population relative to drained controls. There was no detectable difference in the proportion of aerenchyma in drained, flooded and submerged roots of plants from either population. The proportion of aerenchyma increased with root age in the ruderal population. Up to twice the proportion of aerenchyma occurred in the lower third of the root in the turlough population relative to the middle and upper thirds. Submergence in artificially hardened tap water increased the amount of tissue death in the ruderal population, whereas it appeared to enhance the growth of plants from the turlough population relative to that of plants submerged in tap water. Only the ruderal population demonstrated a depth accommodation response in submerged conditions. Root concentrations of ethanol-soluble carbohydrates were up to three times higher in a field- collected turlough population during winter and autumn months than those in a ruderal population. Low levels of ethanol-insoluble carbohydrates were present in the turlough population but were absent from the ruderal population. Starch concentrations fluctuated greatly in the turlough population and were generally higher than those in the ruderal population. These results, together with those from previous investigations, suggest that the turlough population survives prolonged submergence by maintaining low levels of submerged photosynthesis, which may circulate oxygen within the plant tissues, and by utilizing storage carbohydrates for maintenance respiration. Copyright 2003 Annals of Botany Company
Teitel, Zachary; Klimowski, Agnieszka; Campbell, Lesley G
2016-12-07
As global climate change transforms average temperature and rainfall, species distributions may meet, increasing the potential for hybridization and altering individual fitness and population growth. Altered rainfall specifically may shift the strength and direction of selection, also manipulating population trajectories. Here, we investigated the role of interspecific hybridization and selection imposed by rainfall on the evolution of weedy life-history in non-hybrid (Raphanus raphanistrum) and hybrid (R. raphanistrum x R. sativus) populations using a life table response experiment. In documenting long-term population dynamics, we determined intrinsic (r) and asymptotic (λ) population growth rates and sensitivities, a measure of selection imposed on demographic rates. Hybrid populations experienced 8.7-10.3 times stronger selection than wild populations for increased seedling survival. Whereas crop populations generally exhibit little dormancy and wild populations often exhibit dormancy, non-hybrid populations experienced 10% stronger selection than hybrid populations for exhibiting seed dormancy. Selection on survival-to-flowering in wild, not hybrid, populations declined marginally with increasing soil moisture. Hybrid populations exhibited greater r, but not λ, than wild populations regardless of moisture environment. In general, fecundity contributed most to differences in λ but fecundity only contributed positively to hybrid λ relative to wild λ when precipitation was altered (either higher or lower than control) and not under control watering conditions. Selection on key demographic traits may not change dramatically in response to rainfall, and hybridization may more strongly influence the demography of these weedy species than rainfall. If hybrid populations can respond to selection for increased dormancy, this may make it more difficult to deplete weed seed banks and increase the persistence of crop genes in weed populations.
Use of pepper crop residues for the control of root-knot nematodes.
Piedra Buena, A; García-Alvarez, A; Díez-Rojo, M A; Ros, C; Fernández, P; Lacasa, A; Bello, A
2007-11-01
The biofumigant effect of pepper crop residues (PCR) for controlling Meloidogyne incognita populations was evaluated. Under laboratory conditions, 0, 5, 10 and 20 g PCR were applied to 500 g nematode infested soil, with four replicates per treatment. After 20 days at 25 degrees C, PCR reduced significantly M. incognita populations and root galling indices in susceptible tomato cv. Marmande, and increased K, N and organic C in soil. In the field, biofumigation with PCR combined with fresh animal manures (with and without plastic cover), methyl bromide, and a control were evaluated through root galling indices on a pepper crop. Each treatment, except for the control, had a grafted and non-grafted susceptible pepper sub-treatment, with three replicates. Root galling indices were lower, and yields higher, on grafted plants, biofumigation with PCR and plastic cover, with similar values as MB treatment, suggesting that biofumigation with PCR is an efficient non-chemical alternative to control M. incognita populations, especially when applied with plastic cover, nitrogen-rich organic matter and followed by grafting on resistant pepper.
Lack of replication of previous autism spectrum disorder GWAS hits in European populations.
Torrico, Bàrbara; Chiocchetti, Andreas G; Bacchelli, Elena; Trabetti, Elisabetta; Hervás, Amaia; Franke, Barbara; Buitelaar, Jan K; Rommelse, Nanda; Yousaf, Afsheen; Duketis, Eftichia; Freitag, Christine M; Caballero-Andaluz, Rafaela; Martinez-Mir, Amalia; Scholl, Francisco G; Ribasés, Marta; Battaglia, Agatino; Malerba, Giovanni; Delorme, Richard; Benabou, Marion; Maestrini, Elena; Bourgeron, Thomas; Cormand, Bru; Toma, Claudio
2017-02-01
Common variants contribute significantly to the genetics of autism spectrum disorder (ASD), although the identification of individual risk polymorphisms remains still elusive due to their small effect sizes and limited sample sizes available for association studies. During the last decade several genome-wide association studies (GWAS) have enabled the detection of a few plausible risk variants. The three main studies are family-based and pointed at SEMA5A (rs10513025), MACROD2 (rs4141463) and MSNP1 (rs4307059). In our study we attempted to replicate these GWAS hits using a case-control association study in five European populations of ASD patients and gender-matched controls, all Caucasians. Results showed no association of individual variants with ASD in any of the population groups considered or in the combined European sample. We performed a meta-analysis study across five European populations for rs10513025 (1,904 ASD cases and 2,674 controls), seven European populations for rs4141463 (2,855 ASD cases and 36,177 controls) and five European populations for rs4307059 (2,347 ASD cases and 2,764 controls). The results showed an odds ratio (OR) of 1.05 (95% CI = 0.84-1.32) for rs10513025, 1.0002 (95% CI = 0.93-1.08) for rs4141463 and 1.01 (95% CI = 0.92-1.1) for rs4307059, with no significant P-values (rs10513025, P = 0.73; rs4141463, P = 0.95; rs4307059, P = 0.9). No association was found when we considered either only high functioning autism (HFA), genders separately or only multiplex families. Ongoing GWAS projects with larger ASD cohorts will contribute to clarify the role of common variation in the disorder and will likely identify risk variants of modest effect not detected previously. Autism Res 2017, 10: 202-211. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.
Rapid-Adiabatic Control of Ro-Vibrational Populations in Polyatomic Molecules
NASA Astrophysics Data System (ADS)
Zak, Emil J.; Yachmenev, Andrey
2017-06-01
We present a simple method for control of ro-vibrational populations in polyatomic molecules in the presence of inhomogeneous electric fields [1]. Cooling and trapping of heavy polar polyatomic molecules has become one of the frontier goals in high-resolution molecular spectroscopy, especially in the context of parity violation measurement in chiral compounds [2]. A key step toward reaching this goal would be development of a robust and efficient protocol for control of populations of ro-vibrational states in polyatomic, often floppy molecules. Here we demonstrate a modification of the stark-chirped rapid-adiabatic-passage technique (SCRAP) [3], designed for achieving high levels of control of ro-vibrational populations over a selected region in space. The new method employs inhomogeneous electric fields to generate space- and time- controlled Stark-shifts of energy levels in molecules. Adiabatic passage between ro-vibrational states is enabled by the pump pulse, which raises the value of the Rabi frequency. This Stark-chirped population transfer can be used in manipulation of population differences between high-field-seeking and low-field-seeking states of molecules in the Stark decelerator [4]. Appropriate timing of voltages on electric rods located along the decelerator combined with a single pump laser renders our method as potentially more efficient than traditional Stark decelerator techniques. Simulations for NH_3 show significant improvement in effectiveness of cooling, with respect to the standard 'moving-potential' method [5]. At the same time a high phase-space acceptance of the molecular packet is maintained. E. J. Zak, A. Yachmenev (submitted). C. Medcraft, R. Wolf, M. Schnell, Angew. Chem. Int. Ed., 53, 43, 11656-11659 (2014) M. Oberst, H. Munch, T. Halfman, PRL 99, 173001 (2007). K. Wohlfart, F. Grätz, F. Filsinger, H. Haak, G. Meijer, J. Küpper, Phys. Rev. A 77, 031404(R) (2008). H. L. Bethlem, F. M. H. Crompvoets, R. T. Jongma, S. Y. T. van de Meerakker, G. Meijer, Phys. Rev. A, 65, 053416 (2002).
Prevalence of obesity and diabetes in patients with schizophrenia.
Annamalai, Aniyizhai; Kosir, Urska; Tek, Cenk
2017-08-15
To compare the prevalence of diabetes in patients with schizophrenia treated at a community mental health center with controls in the same metropolitan area and to examine the effect of antipsychotic exposure on diabetes prevalence in schizophrenia patients. The study was a comprehensive chart review of psychiatric notes of patients with schizophrenia and schizoaffective disorder treated at a psychosis program in a community mental health center. Data collected included psychiatric diagnoses, diabetes mellitus diagnosis, medications, allergies, primary care status, height, weight, body mass index (BMI), substance use and mental status exam. Local population data was downloaded from the Centers for Disease Control Behavioral Risk Factor Surveillance System. Statistical methods used were χ 2 test, Student's t test, general linear model procedure and binary logistic regression analysis. The study sample included 326 patients with schizophrenia and 1899 subjects in the population control group. Demographic data showed control group was on average 7.6 years older ( P = 0.000), more Caucasians (78.7% vs 38.3%, P = 0.000), and lower percentage of males (40.7% vs 58.3%, P = 0.000). Patients with schizophrenia had a higher average BMI than the subjects in the population control (32.11, SD = 7.72 vs 27.62, SD = 5.93, P = 0.000). Patients with schizophrenia had a significantly higher percentage of obesity (58.5% vs 27%, P = 0.000) than the population group. The patients with schizophrenia also had a much higher rate of diabetes compared to population control (23.9% vs 12.2%, P = 0.000). After controlling for age sex, and race, having schizophrenia was still associated with increased risk for both obesity (OR = 3.25, P = 0.000) and diabetes (OR = 2.42, P = 0.000). The increased risk for diabetes remained even after controlling for obesity (OR = 1.82, P = 0.001). There was no difference in the distribution of antipsychotic dosage, second generation antipsychotic use or multiple antipsychotic use within different BMI categories or with diabetes status in the schizophrenia group. This study demonstrates the high prevalence of obesity and diabetes in schizophrenia patients and indicates that antipsychotics may not be the only contributor to this risk.
21 CFR 520.1443 - Milbemycin oxime and lufenuron.
Code of Federal Regulations, 2014 CFR
2014-04-01
... prevention and control of flea populations, for control of adult Ancylostoma caninum (hookworm), and for removal and control of adult Toxocara canis, Toxascaris leonina (roundworm), and Trichuris vulpis...
21 CFR 520.1443 - Milbemycin oxime and lufenuron.
Code of Federal Regulations, 2013 CFR
2013-04-01
... prevention and control of flea populations, for control of adult Ancylostoma caninum (hookworm), and for removal and control of adult Toxocara canis, Toxascaris leonina (roundworm), and Trichuris vulpis...
Polycystic Ovary-Like Abnormalities (PCO-L) in women with functional hypothalamic amenorrhea.
Robin, G; Gallo, C; Catteau-Jonard, S; Lefebvre-Maunoury, C; Pigny, P; Duhamel, A; Dewailly, D
2012-11-01
In the general population, about 30% of asymptomatic women have polycystic ovary-like abnormalities (PCO-L), i.e. polycystic ovarian morphology (PCOM) at ultrasound and/or increased anti-Müllerian hormone (AMH) serum level. PCOM has also been reported in 30-50% of women with functional hypothalamic amenorrhea (FHA). The aim of this study was to verify whether both PCOM and excessive AMH level indicate PCO-L in FHA and to elucidate its significance. We conducted a retrospective analysis using a database and comparison with a control population. Subjects received ambulatory care in an academic hospital. Fifty-eight patients with FHA were compared to 217 control women with nonendocrine infertility and body mass index of less than 25 kg/m(2). There were no interventions. We measured serum testosterone, androstenedione, FSH, LH, AMH, and ovarian area values. The antral follicle count (AFC) was used as a binary variable (i.e. negative or positive) because of the evolution of its sensitivity over the time of this study. The ability of these variables (except AFC) to detect PCO-L in both populations was tested by cluster analysis. One cluster (cluster 2) suggesting PCO-L was detected in the control population (n = 52; 24%), whereas two such clusters were observed in the FHA population (n = 22 and n = 6; 38 and 10%; clusters 2 and 3, respectively). Cluster 2 in FHA had similar features of PCO-L as cluster 2 in controls, with higher prevalence of positive AFC (70%) and PCOM (70%), higher values of ovarian area and higher serum AMH (P < 0.0001 for all), and testosterone levels (P < 0.01) than in cluster 1. Cluster 3 in FHA was peculiar, with frankly elevated AMH levels. In the whole population (controls + FHA), PCO-L was significantly associated with lower FSH values (P < 0.0001). PCO-L in FHA is a frequent and usually incidental finding of unclear significance, as in controls. The association of PCO-L with hypothalamic amenorrhea should not lead to a mistaken diagnosis of PCOS.
Wu, Yu-Tuan; Luo, Qing-Qing; Li, Xin; Arshad, Bilal; Xu, Zhou; Ran, Liang; Zhao, Chun-Xia; Wu, He; Shi, Yan-Ling; Chen, Hao-Ran; Li, Hao; Li, Hong-Yuan; Wu, Kai-Nan; Kong, Ling-Quan
2018-01-01
Metabolic syndrome has been previously identified as a risk factor for breast cancer and is increasingly a public health concern. This study aims to investigate the prevalence of metabolic syndrome and its components among primary breast cancer and control population. The clinical data of metabolic syndrome and its components in the breast cancer (605 cases) and control population (3212 cases), from Breast Cancer Center and Physical Examination Center of Chongqing, China, from July 2015 to February 2017, were collected for comparative analysis. This study was prospectively registered in Chinese Clinical Trial Registry (http://www.chictr.org.cn/, number: ChiCTR-OOB-15007543). The prevalence of metabolic syndrome in breast cancer (32.6%) was obviously higher than that in control population (18.2%) (p<0.001; OR: 2.173, 95%CI: 1.793 to 2.633). With age stratification, the prevalence of metabolic syndrome in breast cancer group aged below 60 years (24.9%, p<0.001; OR: 2.216, 95%CI: 1.744 to 2.816) and equal/above 60 years (58.3%, p<0.001; OR: 2.291, 95%CI: 1.580 to 3.322) were also statistically higher than those (13.0% & 37.9%) in control population, respectively. Breast cancer women were more likely to have preobese (BMI 25.0-29.9) or obesity (BMI ≥30.0), broader waist circumference, lower HDL-C level, higher systolic and/or diastolic blood pressure and higher fasting blood glucose level compared to the control population, corresponding prevalence were 31.7%vs.19.4%, 76.0%vs.29.6%, 37.4%vs.30.4%, 34.2%/27.3%vs.27.6%/14.2% and 25.0%vs.20.1%, respectively (p<0.01). In summary, there is high prevalence of metabolic syndrome and its components in Chinese breast cancer women, and metabolic syndrome is closely related with breast cancer. Therefore, screening and prevention strategy of metabolic syndrome should be carried out in the management of breast cancer.
Wu, Yu-tuan; Luo, Qing-qing; Li, Xin; Arshad, Bilal; Xu, Zhou; Ran, Liang; Zhao, Chun-xia; Wu, He; Shi, Yan-ling; Chen, Hao-ran; Li, Hao; Li, Hong-yuan; Wu, Kai-nan; Kong, Ling-quan
2018-01-01
Metabolic syndrome has been previously identified as a risk factor for breast cancer and is increasingly a public health concern. This study aims to investigate the prevalence of metabolic syndrome and its components among primary breast cancer and control population. The clinical data of metabolic syndrome and its components in the breast cancer (605 cases) and control population (3212 cases), from Breast Cancer Center and Physical Examination Center of Chongqing, China, from July 2015 to February 2017, were collected for comparative analysis. This study was prospectively registered in Chinese Clinical Trial Registry (http://www.chictr.org.cn/, number: ChiCTR-OOB-15007543). The prevalence of metabolic syndrome in breast cancer (32.6%) was obviously higher than that in control population (18.2%) (p<0.001; OR: 2.173, 95%CI: 1.793 to 2.633). With age stratification, the prevalence of metabolic syndrome in breast cancer group aged below 60 years (24.9%, p<0.001; OR: 2.216, 95%CI: 1.744 to 2.816) and equal/above 60 years (58.3%, p<0.001; OR: 2.291, 95%CI: 1.580 to 3.322) were also statistically higher than those (13.0% & 37.9%) in control population, respectively. Breast cancer women were more likely to have preobese (BMI 25.0-29.9) or obesity (BMI ≥30.0), broader waist circumference, lower HDL-C level, higher systolic and/or diastolic blood pressure and higher fasting blood glucose level compared to the control population, corresponding prevalence were 31.7%vs.19.4%, 76.0%vs.29.6%, 37.4%vs.30.4%, 34.2%/27.3%vs.27.6%/14.2% and 25.0%vs.20.1%, respectively (p<0.01). In summary, there is high prevalence of metabolic syndrome and its components in Chinese breast cancer women, and metabolic syndrome is closely related with breast cancer. Therefore, screening and prevention strategy of metabolic syndrome should be carried out in the management of breast cancer. PMID:29483960
Population density and racial differences in the performance of emergency medical services.
David, Guy; Harrington, Scott E
2010-07-01
This paper analyzes the existence and scope of possible racial differences/disparities in the provision of emergency medical services (EMS) response capability (time from dispatch to arrival at the scene and level of training of the responding team) using data on approximately 120,000 cardiac incidents in the state of Mississippi during 1995-2004. The conceptual framework and empirical analysis focus on the likely effects of population density on the efficient production of EMS as a local public good subject to congestion, and on the need to control adequately for population density to avoid bias in testing for racial differences. Models that control for aggregate population density at the county-level indicate "reverse" disparities: faster estimated response times for African-Americans than for whites. When a refined county-level measure of population density is used that incorporates differences in African-American and white population density by Census tract, the reverse disparity in response times disappears. There also is little or no evidence of race-related differences in the certification level of EMS responders. However, there is evidence that, controlling for response time, African-Americans on average were significantly more likely to be deceased than whites upon EMS arrival at the scene. The overall results are germane to the debate over the scope of conditioning variables that should be included when testing for racial disparities in health care.
Comparative study of cocoa black ants temporal population distribution utilizing geospatial analysis
NASA Astrophysics Data System (ADS)
Adnan, N. A.; Bakar, S.; Mazlan, A. H.; Yusoff, Z. Mohd; Rasam, A. R. Abdul
2018-02-01
Cocoa plantation also subjected to diseases and pests infestation. Some pests not only reduced the yield but also inhibit the growth of trees. Therefore, the Malaysia Cocoa Board (MCB) has explored Cocoa Black Ants (CBA) as one of their biological control mechanism to reduce the pest infestation of the Cocoa Pod Borer (CPB). CPB is capable to cause damage to cocoa beans, and later on will reduce the quality of dried cocoa beans. This study tries to integrate the use of geospatial analysis in understanding population distribution pattern of CBA to enhance its capability in controlling CPB infestation. Two objectives of the study are i) to generate temporal CBA distribution of cocoa plantation for two different blocks, and ii) to compare visually the CBA population distribution pattern with the aid of geospatial technique. This study managed to find the CBA population pattern which indicated spatially modest amount of low pattern distribution in February of 2007 until reaching the highest levels of ant populations in September 2007 and decreasing by the end of the year in 2009 for two different blocks (i.e 10B and 18A). Therefore, the usage of GIS is important to explain the CBA pattern population in the mature cocoa field. This finding might to be used as an indicator to examine the optimum distribution of CBA, which needed as a biological control agent against the CPB in the future.
How to save the rarest Darwin's finch from extinction: the mangrove finch on Isabela Island
Fessl, Birgit; Young, Glyn H.; Young, Richard P.; Rodríguez-Matamoros, Jorge; Dvorak, Michael; Tebbich, Sabine; Fa, John E.
2010-01-01
Habitat destruction and predation by invasive alien species has led to the disappearance of several island populations of Darwin's finches but to date none of the 13 recognized species have gone extinct. However, driven by rapid economic growth in the Galápagos, the effects of introduced species have accelerated and severely threatened these iconic birds. The critically endangered mangrove finch (Camarhynchus heliobates) is now confined to three small mangroves on Isabela Island. During 2006–2009, we assessed its population status and monitored nesting success, both before and after rat poisoning. Population size was estimated at around only 100 birds for the two main breeding sites, with possibly 5–10 birds surviving at a third mangrove. Before rat control, 54 per cent of nests during incubation phase were predated with only 18 per cent of nests producing fledglings. Post-rat control, nest predation during the incubation phase fell to 30 per cent with 37 per cent of nests producing fledglings. During the nestling phase, infestation by larvae of the introduced parasitic fly (Philornis downsi) caused 14 per cent additional mortality. Using population viability analysis, we simulated the probability of population persistence under various scenarios of control and showed that with effective management of these invasive species, mangrove finch populations should start to recover. PMID:20194165
2012-01-01
Background Mass vaccinations of domestic dogs have been shown to effectively control canine rabies and hence human exposure to rabies. Knowledge of dog population demography is essential for planning effective rabies vaccination programmes; however, such information is still rare for African domestic dog populations, particularly so in urban areas. This study describes the demographic structure and population dynamics of a domestic dog population in an urban sub-Saharan African setting. In July to November 2005, we conducted a full household-level census and a cross-sectional dog demography survey in four urban wards of Iringa Municipality, Tanzania. The achievable vaccination coverage was assessed by a two-stage vaccination campaign, and the proportion of feral dogs was estimated by a mark-recapture transect study. Results The estimated size of the domestic dog population in Iringa was six times larger than official town records assumed, however, the proportion of feral dogs was estimated to account for less than 1% of the whole population. An average of 13% of all households owned dogs which equalled a dog:human ratio of 1:14, or 0.31 dogs per household or 334 dogs km-2. Dog female:male ratio was 1:1.4. The average age of the population was 2.2 years, 52% of all individuals were less than one year old. But mortality within the first year was high (72%). Females became fertile at the age of 10 months and reportedly remained fertile up to the age of 11 years. The average number of litters whelped per fertile female per year was 0.6 with an average of 5.5 pups born per litter. The population growth was estimated at 10% y-1. Conclusions Such high birth and death rates result in a rapid replacement of anti-rabies immunised individuals with susceptible ones. This loss in herd immunity needs to be taken into account in the design of rabies control programmes. The very small proportion of truly feral dogs in the population implies that vaccination campaigns aimed at the owned dog population are sufficient to control rabies in urban Iringa, and the same may be valid in other, comparable urban settings. PMID:23217194
White-tailed deer in the Midwest.
USDA FS
1970-01-01
Discusses the present status and future prospects of the nonyarding white-tailed deer population in the Midwestern United States. Range appraisal, habitat, harvest regulation, and population control are included.
Tenzin, Tenzin; Ahmed, Rubaiya; Debnath, Nitish C.; Ahmed, Garba; Yamage, Mat
2015-01-01
Beginning January 2012, a humane method of dog population management using a Catch-Neuter-Vaccinate-Release (CNVR) program was implemented in Dhaka City, Bangladesh as part of the national rabies control program. To enable this program, the size and distribution of the free-roaming dog population needed to be estimated. We present the results of a dog population survey and a pilot assessment of the CNVR program coverage in Dhaka City. Free-roaming dog population surveys were undertaken in 18 wards of Dhaka City on consecutive days using mark-resight methods. Data was analyzed using Lincoln-Petersen index-Chapman correction methods. The CNVR program was assessed over the two years (2012–2013) whilst the coverage of the CNVR program was assessed by estimating the proportion of dogs that were ear-notched (processed dogs) via dog population surveys. The free-roaming dog population was estimated to be 1,242 (95 % CI: 1205–1278) in the 18 sampled wards and 18,585 dogs in Dhaka City (52 dogs/km2) with an estimated human-to-free-roaming dog ratio of 828:1. During the two year CNVR program, a total of 6,665 dogs (3,357 male and 3,308 female) were neutered and vaccinated against rabies in 29 of the 92 city wards. A pilot population survey indicated a mean CNVR coverage of 60.6% (range 19.2–79.3%) with only eight wards achieving > 70% coverage. Given that the coverage in many neighborhoods was below the WHO-recommended threshold level of 70% for rabies eradications and since the CNVR program takes considerable time to implement throughout the entire Dhaka City area, a mass dog vaccination program in the non-CNVR coverage area is recommended to create herd immunity. The findings from this study are expected to guide dog population management and the rabies control program in Dhaka City and elsewhere in Bangladesh. PMID:25978406
Tenzin, Tenzin; Ahmed, Rubaiya; Debnath, Nitish C; Ahmed, Garba; Yamage, Mat
2015-05-01
Beginning January 2012, a humane method of dog population management using a Catch-Neuter-Vaccinate-Release (CNVR) program was implemented in Dhaka City, Bangladesh as part of the national rabies control program. To enable this program, the size and distribution of the free-roaming dog population needed to be estimated. We present the results of a dog population survey and a pilot assessment of the CNVR program coverage in Dhaka City. Free-roaming dog population surveys were undertaken in 18 wards of Dhaka City on consecutive days using mark-resight methods. Data was analyzed using Lincoln-Petersen index-Chapman correction methods. The CNVR program was assessed over the two years (2012-2013) whilst the coverage of the CNVR program was assessed by estimating the proportion of dogs that were ear-notched (processed dogs) via dog population surveys. The free-roaming dog population was estimated to be 1,242 (95 % CI: 1205-1278) in the 18 sampled wards and 18,585 dogs in Dhaka City (52 dogs/km2) with an estimated human-to-free-roaming dog ratio of 828:1. During the two year CNVR program, a total of 6,665 dogs (3,357 male and 3,308 female) were neutered and vaccinated against rabies in 29 of the 92 city wards. A pilot population survey indicated a mean CNVR coverage of 60.6% (range 19.2-79.3%) with only eight wards achieving > 70% coverage. Given that the coverage in many neighborhoods was below the WHO-recommended threshold level of 70% for rabies eradications and since the CNVR program takes considerable time to implement throughout the entire Dhaka City area, a mass dog vaccination program in the non-CNVR coverage area is recommended to create herd immunity. The findings from this study are expected to guide dog population management and the rabies control program in Dhaka City and elsewhere in Bangladesh.
NASA Astrophysics Data System (ADS)
Parshad, Rana D.; Bhowmick, Suman; Quansah, Emmanuel; Basheer, Aladeen; Upadhyay, Ranjit Kumar
2016-10-01
An interesting conundrum in biological control questions the efficiency of generalist predators as biological control agents. Theory suggests, generalist predators are poor agents for biological control, primarily due to mutual interference. However field evidence shows they are actually quite effective in regulating pest densities. In this work we provide a plausible answer to this paradox. We analyze a three species model, where a generalist top predator is introduced into an ecosystem as a biological control, to check the population of a middle predator, that in turn is depredating on a prey species. We show that the inclusion of predator interference alone, can cause the solution of the top predator equation to blow-up in finite time, while there is global existence in the no interference case. This result shows that interference could actually cause a population explosion of the top predator, enabling it to control the target species, thus corroborating recent field evidence. Our results might also partially explain the population explosion of certain species, introduced originally for biological control purposes, such as the cane toad (Bufo marinus) in Australia, which now functions as a generalist top predator. We also show both Turing instability and spatio-temporal chaos in the model. Lastly we investigate time delay effects.
Exposure to diesel and gasoline engine emissions and the risk of lung cancer.
Parent, Marie-Elise; Rousseau, Marie-Claude; Boffetta, Paolo; Cohen, Aaron; Siemiatycki, Jack
2007-01-01
Pollution from motor vehicles constitutes a major environmental health problem. The present paper describes associations between diesel and gasoline engine emissions and lung cancer, as evidenced in a 1979-1985 population-based case-control study in Montreal, Canada. Cases were 857 male lung cancer patients. Controls were 533 population controls and 1,349 patients with other cancer types. Subjects were interviewed to obtain a detailed lifetime job history and relevant data on potential confounders. Industrial hygienists translated each job description into indices of exposure to several agents, including engine emissions. There was no evidence of excess risks of lung cancer with exposure to gasoline exhaust. For diesel engine emissions, results differed by control group. When cancer controls were considered, there was no excess risk. When population controls were studied, the odds ratios, after adjustments for potential confounders, were 1.2 (95% confidence interval: 0.8, 1.8) for any exposure and 1.6 (95% confidence interval: 0.9, 2.8) for substantial exposure. Confidence intervals between risk estimates derived from the two control groups overlapped considerably. These results provide some limited support for the hypothesis of an excess lung cancer risk due to diesel exhaust but no support for an increase in risk due to gasoline exhaust.
Concern With Environmental Deterioration and Attitudes Toward Population Limitation
ERIC Educational Resources Information Center
Barnett, Larry D.
1970-01-01
Analysis of Gallup Poll data of Junuary 1969 reveals weak association between concern about environmental deterioration and the recognition of need for eventual limitation of human population. Suggests that to increase favorable attitudes to population control, role of overpopulation in causing environmental deterioration needs to be presented to…
42 CFR 62.54 - What must applications for the State Loan Repayment Program contain?
Code of Federal Regulations, 2014 CFR
2014-10-01
... area population without health insurance, and the health status of the population as measured by the... will accord special consideration to medically underserved areas with large minority populations; and... additional conditions of the grant. (Approved by the Office of Management and Budget under control number...
42 CFR 62.54 - What must applications for the State Loan Repayment Program contain?
Code of Federal Regulations, 2012 CFR
2012-10-01
... area population without health insurance, and the health status of the population as measured by the... will accord special consideration to medically underserved areas with large minority populations; and... additional conditions of the grant. (Approved by the Office of Management and Budget under control number...
42 CFR 62.54 - What must applications for the State Loan Repayment Program contain?
Code of Federal Regulations, 2013 CFR
2013-10-01
... area population without health insurance, and the health status of the population as measured by the... will accord special consideration to medically underserved areas with large minority populations; and... additional conditions of the grant. (Approved by the Office of Management and Budget under control number...
USDA-ARS?s Scientific Manuscript database
Demographic matrix modeling of invasive plant populations can be a powerful tool to identify key life stage transitions for targeted disruption in order to cause population decline. This approach can provide quantitative estimates of reductions in select vital rates needed to reduce population growt...
Red-cockaded woodpecker population trends and management on Texas national forests
Richard N. Conner; D. Craig Rudolph
1994-01-01
Red-cockaded Woodpecker (Picoides borealis) population trends and concurrent management on four national forests in eastern Texas were evaluated from 1983 through 1993. Following years of decline, populations stabilized and began to increase after intensive management efforts were initiated. Management activities included control of hardwood midstory and understory,...
Fine mapping for SNP markers associated with VSH behavior
USDA-ARS?s Scientific Manuscript database
Varroa Sensitive Hygiene (VSH) is a trait that effectively reduces varroa mite populations by removal of brood cells that contain primarily reproductive mites. Breeding for VSH has proven to be a successful control of mite populations in both pure VSH colonies as well as in out-crossed populations....
Population Growth and Global Security: Toward an American Strategic Commitment.
ERIC Educational Resources Information Center
Mumford, Steven
1981-01-01
Addresses the world population problem by highlighting three crucial areas: the relationship between population growth control and national security issues, the role of American leadership in resolving the problem, and the barriers to effective action. One barrier discussed in detail is the Roman Catholic Church's stand on abortion and…
21 CFR 520.1446 - Milbemcyin oxime and lufenuron tablets.
Code of Federal Regulations, 2012 CFR
2012-04-01
... prevention and control of flea populations, for control of adult Ancylostoma caninum (hookworm), and for removal and control of adult Toxocara canis, Toxascaris leonina (roundworm), and Trichuris vulpis...
21 CFR 520.1446 - Milbemcyin oxime and lufenuron tablets.
Code of Federal Regulations, 2011 CFR
2011-04-01
... prevention and control of flea populations, for control of adult Ancylostoma caninum (hookworm), and for removal and control of adult Toxocara canis, Toxascaris leonina (roundworm), and Trichuris vulpis...
Olaguibel, José María; Quirce, Santiago; Juliá, Berta; Fernández, Cristina; Fortuna, Ana María; Molina, Jesús; Plaza, Vicente
2012-06-22
Asthma Control Questionnaire (ACQ) is a validated tool to measure asthma control. Cut-off points that best discriminate "well-controlled" or "not well-controlled" asthma have been suggested from the analysis of a large randomized clinical trial but they may not be adequate for daily clinical practice. To establish cut-off points of the ACQ that best discriminate the level of control according to Global Initiative for Asthma (GINA) 2006 guidelines in patients with asthma managed at Allergology and Pulmonology Departments as well as Primary Care Centers in Spain. An epidemiological descriptive study, with prospective data collection. Asthma control following GINA-2006 classification and 7-item ACQ was assessed. The study population was split in two parts: 2/3 for finding the cut-off points (development population) and 1/3 for validating the results (validation population). A total of 1,363 stable asthmatic patients were included (mean age 38 ± 14 years, 60.3% women; 69.1% non-smokers). Patient classification according to GINA-defined asthma control was: controlled 13.6%, partially controlled 34.2%, and uncontrolled 52.3%. The ACQ cut-off points that better agreed with GINA-defined asthma control categories were calculated using receiver operating curves (ROC). The analysis showed that ACQ < 0.5 was the optimal cut-off point for "controlled asthma" (sensitivity 74.1%, specificity 77.5%) and 1.00 for "uncontrolled asthma" (sensitivity 73%, specificity 88.2%). Kappa index between GINA categories and ACQ was 0.62 (p < 0.001). The ACQ cut-off points associated with GINA-defined asthma control in a real-life setting were <0.5 for controlled asthma and ≥1 for uncontrolled asthma.
Inoriza, José M; Pérez, Marc; Cols, Montse; Sánchez, Inma; Carreras, Marc; Coderch, Jordi
2013-11-01
To describe the characteristics of a diabetic population, morbidity profile, resource consumption, complications and degree of metabolic control. Cross-sectional study during 2010. Four Health Areas (91.301 people) where the integrated management organization Serveis de Salut integrated Baix Empordà completely provide healthcare assistance. 4.985 diabetic individuals, identified through clinical codes using the ICD-9-MC classification and the 3M? Clinical Risk Groups software. Morbidity profile, related complications and degree of metabolic control were obtained for the target diabetic population. We analyzed the consumption of healthcare resources, pharmaceutical and blood glucose reagent strips. All measurements obtained at individual level. 99.3% of the diabetic population were attended at least once at a primary care center (14.9% of visits). 39.5% of primary care visits and less than 10% of the other scanned resources were related to the management of diabetes. The pharmaceutical expenditure was 25.4% of the population consumption (average cost ?1.014,57). 36.5% of diabetics consumed reagents strips (average cost ?120,65). The more frequent CRG are 5424-Diabetes (27%); 6144-Diabetes and Hypertension (25,5%) and 6143-Diabetes and Other Moderate Chronic Disease (17,2%). The degree of disease control is better in patients not consumers of antidiabetic drugs or treated with oral antidiabetic agents not secretagogues. Comorbidity is decisive in the consumption of resources. Just a few part of this consumption is specifically related to the management of diabetes. Results obtained provide a whole population approach to the main existing studies in our national and regional context. Copyright © 2012 Elsevier España, S.L. All rights reserved.
Mathur, Rohini; Hull, Sally A; Boomla, Kambiz; Robson, John
2012-08-01
Patients with serious mental illness (SMI) have high rates of cardiovascular disease (CVD). In contrast to widespread perception, their access to effective chronic disease management is as high as for the general population. However, previous studies have not included analysis by ethnicity. To identify differences in CVD and diabetes management, by ethnicity, among people with SMI. Three inner east London primary care trusts with an ethnically diverse and socially deprived population. Data were obtained from 147 of 151 general practices. Coded demographic and clinical data were obtained from GP electronic health records using EMIS Web. The sample used was the GP registered population on diabetes or CVD registers (52,620); of these, 1223 also had SMI. The population prevalence of CVD and diabetes is 7.2%; this rises to 18% among those with SMI. People with SMI and CVD or diabetes were found to be as likely to achieve clinical targets as those without SMI. Blood pressure control was significantly better in people with SMI; however, they were more likely to smoke and have a body mass index above 30 kg/m(2). Ethnic differences in care were identified, with south Asian individuals achieving better cholesterol control and black African or Caribbean groups achieving poorer blood pressure control. Risk factor management for those with SMI shows better control of blood pressure and glycosylated haemoglobin than the general population. However, smoking and obesity rates remain high and should be the target of public health programmes. Ethnic differences in management mirror those in the general population. Ethnic monitoring for vulnerable groups provides evidence to support schemes to reduce health inequalities.
Cabrefiga, J.; Francés, J.; Montesinos, E.; Bonaterra, A.
2011-01-01
The efficacy of Pseudomonas fluorescens EPS62e in the biocontrol of Erwinia amylovora was improved by a procedure of physiological adaptation to increase colonization and survival in the phytosphere of rosaceous plants. The procedure consisted of osmoadaptation (OA) and nutritional enhancement (NE). OA was based on saline stress and osmolyte amendment of the growth medium during inoculum preparation. NE consisted of addition of glycine and Tween 80 to the formulation. NE and OA increased the growth rate and carrying capacity of EPS62e under high-relative-humidity (RH) conditions and improved survival at low RH on flowers under controlled environmental conditions. NE did not promote growth or affect infection capacity of E. amylovora. The effect of both methods was tested in the field by following the population of EPS62e using quantitative PCR (Q-PCR) (total population) and CFU counting (culturable population) methods. Following field application, EPS62e colonized blossoms, but it was stressed, as indicated by a sharp decrease in culturable compared to total population levels. However, once established in flowers and at the end of bloom, almost all the total population was culturable. The physiological adaptation treatments increased population levels of EPS62e over those of nonadapted cells during the late stage of the flowering period. Control of fire blight infections in flowers and immature fruits was tested by field application of EPS62e and subsequent inoculation with E. amylovora under controlled-environment conditions. The efficacy of fire blight control increased significantly with the combination of nutritional enhancement and osmoadaptation, in comparison with the absence of physiological adaptation. PMID:21441337
The role of ancestry in TB susceptibility of an admixed South African population.
Daya, Michelle; van der Merwe, Lize; van Helden, Paul D; Möller, Marlo; Hoal, Eileen G
2014-07-01
Genetic susceptibility to tuberculosis (TB) has been well established and this, taken together with variation in susceptibility observed between different geographic and ethnic populations, implies that susceptibility to TB may in part be affected by ethnicity. In a previous genome-wide TB case-control study (642 cases and 91 controls) of the admixed South African Coloured (SAC) population, we found a positive correlation between African San ancestry and TB susceptibility, and negative correlations with European and Asian ancestries. Since genome-wide data was available for only a small number of controls in the previous study, we endeavored to validate this finding by genotyping a panel of ancestry informative markers (AIMs) in additional individuals, yielding a data set of 918 cases and 507 controls. Ancestry proportions were estimated using the AIMs for each of the source populations of the SAC (African San, African non-San, European, South Asian and East Asian). Using logistic regression models to test for association between TB and ancestry, we confirmed the substantial effect of ancestry on TB susceptibility. We also investigated the effect of adjusting for ancestry in candidate gene TB association studies of the SAC. We report a polymorphism that is no longer significantly associated with TB after adjustment for ancestry, a polymorphism that is significantly associated with TB only after adjustment for ancestry, and a polymorphism where the association significance remains unchanged. By comparing the allele frequencies of these polymorphisms in the source populations of the SAC, we demonstrate that association results are likely to be affected by adjustment for ancestry if allele frequencies differ markedly in the source populations of the SAC. Copyright © 2014 Elsevier Ltd. All rights reserved.
Dai, Yaoyao; Zhang, Xia; Pan, Hongqiu; Tang, Shaowen; Shen, Hongbing; Wang, Jianming
2011-10-22
Recently, one genome-wide association study identified a susceptibility locus of rs4331426 on chromosome 18q11.2 for tuberculosis in the African population. To validate the significance of this susceptibility locus in other areas, we conducted a case-control study in the Chinese population. The present study consisted of 578 cases and 756 controls. The SNP rs4331426 and other six tag SNPs in the 100 Kbp up and down stream of rs4331426 on chromosome 18q11.2 were genotyped by using the Taqman-based allelic discrimination system. As compared with the findings from the African population, genetic variation of the SNP rs4331426 was rare among the Chinese. No significant differences were observed in genotypes or allele frequencies of the tag SNPs between cases and controls either before or after adjusting for age, sex, education, smoking, and drinking history. However, we observed strong linkage disequilibrium of SNPs. Constructed haplotypes within this block were linked the altered risks of tuberculosis. For example, in comparison with the common haplotype AA(rs8087945-rs12456774), haplotypes AG(rs8087945-rs12456774) and GA(rs8087945-rs12456774) were associated with a decreased risk of tuberculosis, with the adjusted odds ratio(95% confidence interval) of 0.34(0.27-0.42) and 0.22(0.16-0.29), respectively. Susceptibility locus of rs4331426 discovered in the African population could not be validated in the Chinese population. None of genetic polymorphisms we genotyped were related to tuberculosis in the single-point analysis. However, haplotypes on chromosome 18q11.2 might contribute to an individual's susceptibility. More work is necessary to identify the true causative variants of tuberculosis.
Effects of dietary cooked navy bean on the fecal microbiome of healthy companion dogs.
Kerr, Katherine R; Forster, Genevieve; Dowd, Scot E; Ryan, Elizabeth P; Swanson, Kelly S
2013-01-01
Cooked bean powders are a promising novel protein and fiber source for dogs, which have demonstrated potential to alter microbial composition and function for chronic disease control and prevention. This study aimed to determine the impact of cooked navy bean powder fed as a staple food ingredient on the fecal microbiome of healthy adult pet dogs. Fecal samples from healthy dogs prior to dietary control and after 4 wk of dietary treatment with macro- and micronutrient matched diets containing either 0 or 25% cooked navy beans (n = 11 and n = 10, respectively) were analyzed by 454-pyrosequencing of the 16S rRNA gene. There were few differences between dogs fed the control and navy bean diets after 4 wk of treatment. These data indicate that there were no major effects of navy bean inclusion on microbial populations. However, significant differences due to dietary intervention onto both research diets were observed (i.e., microbial populations at baseline versus 4 wk of intervention with 0 or 25% navy bean diets). After 4 wk of dietary intervention on either control or navy bean diet, the Phylum Firmicutes was increased and the Phyla Actinobacteria and Fusobacteria were decreased compared to baseline. No negative alterations of microbial populations occurred following cooked navy bean intake in dogs, indicating that bean powders may be a viable protein and fiber source for commercial pet foods. The highly variable microbial populations observed in these healthy adult pet dogs at baseline is one potential reason for the difficulty to detect alterations in microbial populations following dietary changes. Given the potential physiological benefits of bean intake in humans and dogs, further evaluation of the impacts of cooked navy bean intake on fecal microbial populations with higher power or more sensitive methods are warranted.
Forlani, Lucas; Pedrini, Nicolás; Girotti, Juan R.; Mijailovsky, Sergio J.; Cardozo, Rubén M.; Gentile, Alberto G.; Hernández-Suárez, Carlos M.; Rabinovich, Jorge E.; Juárez, M. Patricia
2015-01-01
Background Current Chagas disease vector control strategies, based on chemical insecticide spraying, are growingly threatened by the emergence of pyrethroid-resistant Triatoma infestans populations in the Gran Chaco region of South America. Methodology and findings We have already shown that the entomopathogenic fungus Beauveria bassiana has the ability to breach the insect cuticle and is effective both against pyrethroid-susceptible and pyrethroid-resistant T. infestans, in laboratory as well as field assays. It is also known that T. infestans cuticle lipids play a major role as contact aggregation pheromones. We estimated the effectiveness of pheromone-based infection boxes containing B. bassiana spores to kill indoor bugs, and its effect on the vector population dynamics. Laboratory assays were performed to estimate the effect of fungal infection on female reproductive parameters. The effect of insect exuviae as an aggregation signal in the performance of the infection boxes was estimated both in the laboratory and in the field. We developed a stage-specific matrix model of T. infestans to describe the fungal infection effects on insect population dynamics, and to analyze the performance of the biopesticide device in vector biological control. Conclusions The pheromone-containing infective box is a promising new tool against indoor populations of this Chagas disease vector, with the number of boxes per house being the main driver of the reduction of the total domestic bug population. This ecologically safe approach is the first proven alternative to chemical insecticides in the control of T. infestans. The advantageous reduction in vector population by delayed-action fungal biopesticides in a contained environment is here shown supported by mathematical modeling. PMID:25969989
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hwang, Chiachi; Wu, Weimin; Gentry, Terry J.
2009-05-22
Bacterial community succession was investigated in a field-scale subsurface reactor formed by a series of wells that received weekly ethanol additions to re-circulating groundwater. Ethanol additions stimulated denitrification, metal reduction, sulfate reduction, and U(VI) reduction to sparingly soluble U(IV). Clone libraries of SSU rRNA gene sequences from groundwater samples enabled tracking of spatial and temporal changes over a 1.5 y period. Analyses showed that the communities changed in a manner consistent with geochemical variations that occurred along temporal and spatial scales. Canonical correspondence analysis revealed that the levels of nitrate, uranium, sulfide, sulfate, and ethanol strongly correlated with particular bacterialmore » populations. As sulfate and U(VI) levels declined, sequences representative of sulfate-reducers and metal-reducers were detected at high levels. Ultimately, sequences associated with sulfate-reducing populations predominated, and sulfate levels declined as U(VI) remained at low levels. When engineering controls were compared to the population variation via canonical ordination, changes could be related to dissolved oxygen control and ethanol addition. The data also indicated that the indigenous populations responded differently to stimulation for bio-reduction; however, the two bio-stimulated communities became more similar after different transitions in an idiosyncratic manner. The strong associations between particular environmental variables and certain populations provide insight into the establishment of practical and successful remediation strategies in radionuclide-contaminated environments with respect to engineering controls and microbial ecology.« less
Sobecky, P. A.; Schell, M. A.; Moran, M. A.; Hodson, R. E.
1996-01-01
An indigenous marine Achromobacter sp. was isolated from coastal Georgia seawater and modified in the laboratory by introduction of a plasmid with a phoA hybrid gene that directed constitutive overproduction of alkaline phosphatase. The effects of this "indigenous" genetically engineered microorganism (GEM) on phosphorus cycling were determined in seawater microcosms following the addition of a model dissolved organic phosphorus compound, glycerol 3-phosphate, at a concentration of 1 or 10 (mu)M. Within 48 h, a 2- to 10-fold increase in the concentration of inorganic phosphate occurred in microcosms containing the GEM (added at an initial density equivalent to 8% of the total bacterial population) relative to controls containing only natural microbial populations, natural populations with the unmodified Achromobacter sp., or natural populations with the Achromobacter sp. containing the plasmid but not the phoA gene. Secondary effects of the GEM on the phytoplankton community were observed after several days, evident as sustained increases in phytoplankton biomass (up to 14-fold) over that in controls. Even in the absence of added glycerol 3-phosphate, a numerically stable GEM population (averaging 3 to 5% of culturable bacteria) was established within 2 to 3 weeks of introduction into seawater. Moreover, alkaline phosphatase activity in microcosms with the GEM was substantially higher than that in controls for up to 25 days, and microcosms containing the GEM maintained the potential for net phosphate accumulation above control levels for longer than 1 month. PMID:16535222
Arce Arnáez, Araceli; Cabello Ballesteros, Luisa; Iñigo Martínez, Jesús
2007-03-01
To study a community outbreak of hepatitis A in a marginal population and the public health response in order to bring it under control. Descriptive study of the outbreak that occurred in February-June, 2004. An epidemiological survey was conducted to detect prior cases and active vigilance was set up. Case and susceptibility definitions were established. A gypsy population in Madrid, Spain. They had basic provision of sewerage, water supply and waste disposal. A population of 550 in census; estimated population, 800. 70% were under 40 and 55% were illiterate. Control measures were: a) health education activities to strengthen habits of hygiene, and b) immunisation of susceptible individuals. A total of 646 people were vaccinated, with the active help of staff from the Institute of Rehousing and Integration into Society. The outbreak affected 26 people, with an average age of 8 (95% CI, 6.2-9.8), similar distribution by sex and 3.3% attack rate. Fourteen cases were students at state schools, not all in the same classes. There were 7 pairs of siblings among the cases. The diagnosis was conformed by serology in 17 cases. Five needed hospital admission. The epidemic curve suggested person-person transmission. All those affected were under 20 years old. Vaccination was seen to be effective in controlling the outbreak. Interventions were assisted by intermediaries in order to respect the gypsies' cultural context and were well accepted.
Di Lonardo, Anna; Donfrancesco, Chiara; Palmieri, Luigi; Vanuzzo, Diego; Giampaoli, Simona
2017-06-01
High blood pressure (BP) is a major risk factor for cardiovascular disease. The urgency of the problem was underlined by the World Health Organization (WHO) Global Action Plan for the prevention and control of noncommunicable diseases, which recommends a 25% relative reduction in the prevalence of raised BP by 2020. A surveillance system represents a useful tool to monitor BP in the general population. Since 1980s, the National Institute of Health has conducted several surveys of the adult general population, measuring cardiovascular risk factors by standardized procedures and methods. To describe mean BP levels and high BP prevalence from 1978 to 2012 by sex and quinquennia of age. Data were derived from the following three studies: (i) Risk Factors and Life Expectancy (RIFLE), conducted between 1978 and 2002 in 13 Italian regions (>70,000 persons); (ii) Osservatorio Epidemiologico Cardiovascolare (OEC), conducted between 1998-2002 in the general population from all Italian regions (>9000 persons); and (iii) Osservatorio Epidemiologico Cardiovascolare/Health Examination Survey (OEC/HES), conducted between 2008-2012 in the general population from all Italian regions (>9000 persons). A significant decrease in mean systolic and diastolic BP levels and prevalence of high BP from 1978 to 2012 was observed both in men and women. BP and high BP increased by age classes in all considered periods. BP awareness and control also improved. Our data suggest that BP control could be achieved by 2020, as recommended by WHO.
Akbari, Zahra; Safari-Alighiarloo, Nahid; Taleghani, Mohammad Yaghoob; Mirfakhar, Farzaneh Sadat; Asadzadeh Aghdaei, Hamid; Vahedi, Mohsen; Irani Shemirani, Atena; Nazemalhosseini-Mojarad, Ehsan; Zali, Mohammad Reza
2014-01-01
Aim: The purpose of this study was to evaluate the influence of intronic polymorphism of the SMAD7 (Mothers Against Decantaplegic Homolog 7) gene (rs2337104) on the risk of colorectal cancer (CRC) and clinicopathological features in an Iranian population. Background: SMAD7 has been identified as an antagonist of transforming growth factor beta (TGF-b)-mediating fibrosis, carcinogenesis, and inflammation. Regarding to the recent genome-wide scan, a risk locus for colorectal cancer at 18q21 has been found, which maps to the SMAD7 gene. Patients and methods: This case-control study was performed on 109 CRC patients and 109 healthy controls recruited in Taleghani Hospital. The genotyping of all samples were done by TaqMan assay via an ABI 7500 Real Time PCR System (Applied Biosystems) with DNA from peripheral blood. The association of this polymorphism with the risk of CRC and clinicopathological features was investigated. Results: Our results indicated that there were no significant association between genotypic and allelic frequencies of SMAD7 polymorphism (rs2337104) and CRC risk in our population. Although the T allele is the most frequent one in this population and its frequency was 86.7% in patients compared with 91.7% in controls (OR=1.705, 95% CI= 0.916–3.172). Also, the SMAD7 genotypes were not associated with any clinicopathological characteristics in CRC patients (P>0.05). Conclusion: For the first time, this study results revealed that this SMAD7 polymorphism couldn’t be a potential risk factor for CRC or a prognostic biomarker for prediction of clinicopathological features in an Iranian population. A large-scale case-control study is needed to validate our results. PMID:25289133
Faeh, David; William, Julita; Tappy, Luc; Ravussin, Eric; Bovet, Pascal
2007-07-19
The evidence for a "diabesity" epidemic is accumulating worldwide but population-based data are still scarce in the African region. We assessed the prevalence, awareness and control of diabetes (DM) in the Seychelles, a rapidly developing country in the African region. We also examined the relationship between body mass index, fasting serum insulin and DM. Examination survey in a sample representative of the entire population aged 25-64 of the Seychelles, attended by 1255 persons (participation rate of 80.2%). An oral glucose tolerance test (OGTT) was performed in individuals with fasting blood glucose between 5.6 and 6.9 mmol/l. Diabetes mellitus (DM), impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) were defined along criteria of the ADA. Prevalence estimates were standardized for age. The prevalence of DM was 11.5% and 54% of persons with DM were aware of having DM. Less than a quarter of all diabetic persons under treatment were well controlled for glycemia (HbA1c), blood pressure or LDL-cholesterol. The prevalence of IGT and IFG were respectively 10.4% and 24.2%. The prevalence of excess weight (BMI > or = 25 kg/m2) and obesity (BMI > or = 30 kg/m2) was respectively 60.1% and 25.0%. Half of all DM cases in the population could be attributed to excess weight. We found a high prevalence of DM and pre-diabetes in a rapidly developing country in the African region. The strong association between overweight and DM emphasizes the importance of weight control measures to reduce the incidence of DM in the population. High rates of diabetic persons not aware of having DM in the population and insufficient cardiometabolic control among persons treated for DM stress the need for intensifying health care for diabetes.
Sayan, Harutai; Assavacheep, Pornchalit; Angkanaporn, Kris; Assavacheep, Anongnart
2018-04-12
Gut health improvements were monitored with respect to growth performance, diarrhea incidence, fecal bacterial population and intestinal morphology of suckling pigs orally supplemented with live Lactobacillus salivarius oral suspensions and challenged with F4+ enterotoxigenic Escherichia coli (ETEC). Two groups of newborn pigs from 18 multiparous sows were randomly designated as non-supplemented (control: n=114 piglets) and L. salivarius supplemented groups (treatment: n=87 piglets). Treatment pigs were orally administered with 2 ml of 109 CFU/ml L. salivarius on days 1 - 3, then they were orally administered with 5 ml of 109 CFU/ml L. salivarius on days 4 - 10, while those in control group received an equal amount of phosphate buffered saline solution (PBS). On day 24 (2 weeks post supplementation), one pig per replicate of both groups was orally administered with 108 CFU/ml F4+ ETEC, then they were euthanized on day 29 of experiment. Results revealed that pigs in treatment group had statistically significant in average daily gain (ADG), body weight and weight gain, and tended to lower diarrhea throughout the study. Numbers of Lactobacillus population in feces of treatment pigs were higher than control pigs, especially on day 10 of study. Numbers of total bacteria in intestinal contents of control pigs were also increased, but not Coliform and Lactobacillus populations. Histological examination revealed statistically significant improvement of villous height and villous/crypt ratio of duodenum, proximal jejunum and distal jejunum parts of treatment pigs better than control. Duodenal pH of treatment group was significantly decreased. Oral supplementation of live L. salivarius during the first 10 days of suckling pig promoted growth performance and guts health, reduced diarrhea incidence, and increased fecal Lactobacillus populations, and improved intestinal morphology.
NASA Astrophysics Data System (ADS)
Shinozaki, Takashi; Okada, Masato; Reyes, Alex D.; Câteau, Hideyuki
2010-01-01
Intermingled neural connections apparent in the brain make us wonder what controls the traffic of propagating activity in the brain to secure signal transmission without harmful crosstalk. Here, we reveal that inhibitory input but not excitatory input works as a particularly useful traffic controller because it controls the degree of synchrony of population firing of neurons as well as controlling the size of the population firing bidirectionally. Our dynamical system analysis reveals that the synchrony enhancement depends crucially on the nonlinear membrane potential dynamics and a hidden slow dynamical variable. Our electrophysiological study with rodent slice preparations show that the phenomenon happens in real neurons. Furthermore, our analysis with the Fokker-Planck equations demonstrates the phenomenon in a semianalytical manner.
Environmental Tobacco Smoke and Adult-Onset Asthma: A Population-Based Incident Case–Control Study
Jaakkola, Maritta S.; Piipari, Ritva; Jaakkola, Niina; Jaakkola, Jouni J. K.
2003-01-01
Objectives. The authors assessed the effects of environmental tobacco smoke (ETS) on the development of asthma in adults. Methods. In the Pirkanmaa district of South Finland, all 21- to 63-year-old adults with new cases of asthma diagnosed during a 2.5-year period (n = 521 case patients, out of 441 000 inhabitants) and a random sample of control subjects from the source population (932 control subjects) participated in a population-based incident case–control study. Results. Risk of asthma was related to workplace ETS exposure (adjusted odds ratio [OR] = 2.16; 95% confidence interval [CI] = 1.26, 3.72) and home exposure (OR = 4.77; 95% CI = 1.29, 17.7) in the past year. Cumulative ETS exposure over a lifetime at work and at home increased the risk. Conclusions. This study indicates for the first time that both cumulative lifetime and recent ETS exposures increase the risk of adult-onset asthma. PMID:14652334
Uejio, Christopher K; Hayden, Mary H; Zielinski-Gutierrez, Emily; Lopez, Jose Luis Robles; Barrera, Roberto; Amador, Manuel; Thompson, Gregory; Waterman, Stephen H
2014-06-01
Dengue periodically circulates in southern Texas and neighboring Tamaulipas, Mexico; thus, a closer examination of human and vector ecology at the northern limits of North American transmission may improve prevention activities. Scrap tires produce large mosquito populations and increase the risk of dengue transmission. Some households choose not to pay tire disposal fees, and many tires are illegally dumped in residential areas. Biological control may provide low-cost and environmentally friendly mosquito control. This pilot study evaluated the ability of Mesocyclops longisetus to reduce mosquito populations in existing residential scrap tire piles. Mosquito populations were measured by the number of all mosquito pupae within tires or adult Aedes aegypti and Ae. albopictus near piles. Mesocyclops longisetus treated piles did not significantly reduce total mosquito pupae (P = 0.07) in Matamoros, Mexico. The study also evaluated the efficacy of native Toxorhynchites moctezuma which preferentially colonized tire piles under vegetation cover in Brownsville, TX. Toxorhynchites moctezuma larvae significantly reduced total mosquito pupae, but the strength of control diminished over time.
Velásquez Pereira, Leydi Carolina; Vargas Castellanos, Clara Inés; Silva Sieger, Federico Arturo
2016-12-30
To analyze if there is an association between the presence of polymorphisms in the LPL gene (rs320, rs285 and rs328) with development of acute ischemic stroke in Colombian population. In a case control design, 133 acute ischemic stroke patients (clinical diagnosis and x-ray CT) and 269 subjects without stroke as controls were studied. PCR -RFLP technique was used to detect rs320, rs285 and rs328 polymorphisms in the LPL gene. In the present research was not found any association between any of the LPL gene polymorphism and acute ischemic stroke in the population studied; the allele and genotypic frequencies of the studied polymorphisms were similar in cases and controls and followed the Hardy-Weinberg equilibrium. The study was approved by the IRB and each subject signed the informed consent. LPL gene polymorphisms are not genetic markers for the development of stroke in the Colombian sample used.
Opioid system genes in alcoholism: a case-control study in Croatian population.
Cupic, B; Stefulj, J; Zapletal, E; Matosic, A; Bordukalo-Niksic, T; Cicin-Sain, L; Gabrilovac, J
2013-10-01
Due to their involvement in dependence pathways, opioid system genes represent strong candidates for association studies investigating alcoholism. In this study, single nucleotide polymorphisms within the genes for mu (OPRM1) and kappa (OPRK1) opioid receptors and precursors of their ligands - proopiomelanocortin (POMC), coding for beta-endorphin and prodynorphin (PDYN) coding for dynorphins, were analyzed in a case-control study that included 354 male alcohol-dependent and 357 male control subjects from Croatian population. Analysis of allele and genotype frequencies of the selected polymorphisms of the genes OPRM1/POMC and OPRK1/PDYN revealed no differences between the tested groups. The same was true when alcohol-dependent persons were subdivided according to the Cloninger's criteria into type-1 and type-2 groups, known to differ in the extent of genetic control. Thus, the data obtained suggest no association of the selected polymorphisms of the genes OPRM1/POMC and OPRK1/PDYN with alcoholism in Croatian population. Copyright © 2013 Elsevier Ltd. All rights reserved.
Epidemiology & Genomics Research Program
The Epidemiology and Genomics Research Program, in the National Cancer Institute's Division of Cancer Control and Population Sciences, funds research in human populations to understand the determinants of cancer occurrence and outcomes.
THE MUSHROOM CROWD: SOCIAL AND POLITICAL ASPECTS OF POPULATION PRESSURE.
ANDERSON, L S
1964-12-05
The meaning of population pressure is discussed and, with the help of a formula, its five main components (people, rate of increase of people, food-producing acreage, protein nutrition and industrialization) are analyzed.Factors which have eased population pressure in the past are considered under the headings of political violence (war and genocide), natural disaster (famine and disease), and social action (increased local protein supply, emigration, industrialization and birth control).Birth control is the first prerequisite to an easing of population pressure; the effectiveness of the Japanese and the Indian programs is discussed.The crippling burden of preventable disease, shown to be a major obstacle to the development of sophisticated industries, presents a challenge to Western medical men who so far have done little to meet it.
Dynamic Model for Life History of Scyphozoa
Xie, Congbo; Fan, Meng; Wang, Xin; Chen, Ming
2015-01-01
A two-state life history model governed by ODEs is formulated to elucidate the population dynamics of jellyfish and to illuminate the triggering mechanism of its blooms. The polyp-medusa model admits trichotomous global dynamic scenarios: extinction, polyps survival only, and both survival. The population dynamics sensitively depend on several biotic and abiotic limiting factors such as substrate, temperature, and predation. The combination of temperature increase, substrate expansion, and predator diminishment acts synergistically to create a habitat that is more favorable for jellyfishes. Reducing artificial marine constructions, aiding predator populations, and directly controlling the jellyfish population would help to manage the jellyfish blooms. The theoretical analyses and numerical experiments yield several insights into the nature underlying the model and shed some new light on the general control strategy for jellyfish. PMID:26114642
Dynamic Model for Life History of Scyphozoa.
Xie, Congbo; Fan, Meng; Wang, Xin; Chen, Ming
2015-01-01
A two-state life history model governed by ODEs is formulated to elucidate the population dynamics of jellyfish and to illuminate the triggering mechanism of its blooms. The polyp-medusa model admits trichotomous global dynamic scenarios: extinction, polyps survival only, and both survival. The population dynamics sensitively depend on several biotic and abiotic limiting factors such as substrate, temperature, and predation. The combination of temperature increase, substrate expansion, and predator diminishment acts synergistically to create a habitat that is more favorable for jellyfishes. Reducing artificial marine constructions, aiding predator populations, and directly controlling the jellyfish population would help to manage the jellyfish blooms. The theoretical analyses and numerical experiments yield several insights into the nature underlying the model and shed some new light on the general control strategy for jellyfish.
Hierarchical model analysis of the Atlantic Flyway Breeding Waterfowl Survey
Sauer, John R.; Zimmerman, Guthrie S.; Klimstra, Jon D.; Link, William A.
2014-01-01
We used log-linear hierarchical models to analyze data from the Atlantic Flyway Breeding Waterfowl Survey. The survey has been conducted by state biologists each year since 1989 in the northeastern United States from Virginia north to New Hampshire and Vermont. Although yearly population estimates from the survey are used by the United States Fish and Wildlife Service for estimating regional waterfowl population status for mallards (Anas platyrhynchos), black ducks (Anas rubripes), wood ducks (Aix sponsa), and Canada geese (Branta canadensis), they are not routinely adjusted to control for time of day effects and other survey design issues. The hierarchical model analysis permits estimation of year effects and population change while accommodating the repeated sampling of plots and controlling for time of day effects in counting. We compared population estimates from the current stratified random sample analysis to population estimates from hierarchical models with alternative model structures that describe year to year changes as random year effects, a trend with random year effects, or year effects modeled as 1-year differences. Patterns of population change from the hierarchical model results generally were similar to the patterns described by stratified random sample estimates, but significant visibility differences occurred between twilight to midday counts in all species. Controlling for the effects of time of day resulted in larger population estimates for all species in the hierarchical model analysis relative to the stratified random sample analysis. The hierarchical models also provided a convenient means of estimating population trend as derived statistics from the analysis. We detected significant declines in mallard and American black ducks and significant increases in wood ducks and Canada geese, a trend that had not been significant for 3 of these 4 species in the prior analysis. We recommend using hierarchical models for analysis of the Atlantic Flyway Breeding Waterfowl Survey.
Reuter, Sandra; Scriberras, James; Reynolds, Rosy; Brown, Nicholas M.; Török, M. Estée; James, Richard; Network, East of England Microbiology Research; Aanensen, David M.; Bentley, Stephen D.; Holden, Matthew T. G.; Parkhill, Julian; Spratt, Brian G.; Peacock, Sharon J.
2017-01-01
Antibiotic resistance forms a serious threat to the health of hospitalised patients, rendering otherwise treatable bacterial infections potentially life-threatening. A thorough understanding of the mechanisms by which resistance spreads between patients in different hospitals is required in order to design effective control strategies. We measured the differences between bacterial populations of 52 hospitals in the United Kingdom and Ireland, using whole-genome sequences from 1085 MRSA clonal complex 22 isolates collected between 1998 and 2012. The genetic differences between bacterial populations were compared with the number of patients transferred between hospitals and their regional structure. The MRSA populations within single hospitals, regions and countries were genetically distinct from the rest of the bacterial population at each of these levels. Hospitals from the same patient referral regions showed more similar MRSA populations, as did hospitals sharing many patients. Furthermore, the bacterial populations from different time-periods within the same hospital were generally more similar to each other than contemporaneous bacterial populations from different hospitals. We conclude that, while a large part of the dispersal and expansion of MRSA takes place among patients seeking care in single hospitals, inter-hospital spread of resistant bacteria is by no means a rare occurrence. Hospitals are exposed to constant introductions of MRSA on a number of levels: (1) most MRSA is received from hospitals that directly transfer large numbers of patients, while (2) fewer introductions happen between regions or (3) across national borders, reflecting lower numbers of transferred patients. A joint coordinated control effort between hospitals, is therefore paramount for the national control of MRSA, antibiotic-resistant bacteria and other hospital-associated pathogens. PMID:29026654
Helleberg, Marie; Gerstoft, Jan; Afzal, Shoaib; Kronborg, Gitte; Larsen, Carsten S; Pedersen, Court; Bojesen, Stig E; Nordestgaard, Børge G; Obel, Niels
2014-06-19
The relative impact of immune deficiency and lifestyle-related factors on risk of cancer in the HIV-infected population is controversial. We aimed to estimate the population-attributable fractions (PAFs) associated with smoking, being HIV-infected and with immune deficiency. In a Danish, nationwide, population-based cohort study (1995-2011), incidences of cancer were compared between an HIV-infected cohort and a population-based matched cohort in analyses stratified on cancer category, smoking status and for HIV patients: low CD4 cell count. We included 3503 HIV patients [baseline CD4+ 450 cells/μl (inter-quartile range 310-630)] and 12,979 population controls. Smoking-related and virological cancers accounted for 23 and 43% of cancers in the HIV-infected population. The risk of these cancers were higher among HIV patients compared to controls [incidence rate ratio (IRR) 2.8, 95% confidence interval (CI) 1.6-4.9; and IRR 11.5, 95% CI 6.5-20.5], whereas the risk of other cancers did not differ (IRR 1.0, 95% CI 0.7-1.3). Non-smoking HIV patients did not have increased risk of non-virological cancers compared to non-smoking controls (IRR 1.2, 95% CI 0.7-2.1). The PAFs of cancer associated with smoking and with being HIV-infected were 27 and 49%, respectively. For cancers not strongly related to smoking or viral infections, the PAFs associated with being HIV-infected and with immune deficiency were 0%. The risk of cancer is increased in HIV patients compared to the background population. In absence of smoking, the increase in risk is confined to cancers related to viral infections, whereas the risk of other cancers is not elevated and does not seem to be associated with immune deficiency.
Davies, Jamie T; Ireson, John E; Allen, Geoff R
2009-02-01
Predation by the phytoseiid mite, Phytoseiulus persimilis, is considered a major threat to the effectiveness of biological control of gorse, Ulex europaeus, using Tetranychus lintearius. To assess this threat and to determine if the impact of P. persimilis on T. lintearius populations is comparable to its impact on T. urticae populations, its development and predator : prey generation time ratios were assessed. The pre-adult mortality and development time of two populations of P. persimilis fed on two diets, T. urticae and T. lintearius, were determined at two temperatures, 14 and 24 degrees C. There were no significant differences in either mortality or development time between the two populations of P. persimilis at these temperatures. There is therefore no evidence that the two tested populations of P. persimilis are behaving as different strains. Similarly, diet had no significant effect on either mortality or development time at these temperatures. At 14 degrees C the mortality of P. persimilis was significantly higher and development was significantly longer than at 24 degrees C. Using pre-adult development as a surrogate for generation times, predator : prey generation time ratios were calculated between P. persimilis and both T. urticae and T. lintearius using data from this and other studies. The predator : prey generation time ratios between P. persimilis and T. lintearius were lower than those between P. persimilis and T. urticae. These results indicate that the impact of P. persimilis on T. lintearius populations is likely to be comparable to its impact on T. urticae populations. This provides further evidence that predation by P. persimilis is having a deleterious effect on T. lintearius populations and therefore reducing its effectiveness as a biological control agent for gorse.
Population growth and economic development: two new U.S. perspectives.
Wulf, D; Klitsch, M
1986-01-01
This report compares the research paths of economic development reports by the US National Academy of Sciences (NAS) and the American Assembly of Columbia University. The NAS group, made up principally of economists and demographers, refrained from recommending population reduction targets, in contrast to the stronger terms of its 1971 report. A 1965 report by the Assembly spoke of population as a serious negative influence for economic development, political stability, and world peace, while the new report speaks of negative socioeconomic effects, and of the limiting of a person's right to control family size. The NAS agenda was established before the US delegation to the UN population conference in Mexico City retreated from declaring population growth to be a necessarily negative influencer of socioeconomic progress. The Assembly took the position that possible benefits of population growth would be far outweighed by factors such as resource depletion and women's health. The NAS maintained that growth might provide incentives for institutional adjustments (market development, investment in education) and control of growth should not be considered a substitute for such interventions. Both reports agree that control of fertility is a human right, but the NAS report examined the question of the acceptable degree of compulsion to be used to encourage couples. The Assembly objected to limiting access to family planning by defunding abortion programs oversease. Differences exist between the 2 reports in questins such as the negative impact of 1950's population growth, the synergistic effect of growth on many areas of human activity, the extent to which welfare of future generations is considered relevant today, and the adequacy of pure economic analysis in assessing need. Much study of population/development linkages is still required.
Hanly, Patrick J; Haase, Amanda T
2016-05-01
The size and success of epidemiologically significant adult mosquito populations are inherently tied to the conditions of the aquatic habitat in which juvenile stages grow until eclosion. While resource competition and quality are well-established controls to juvenile growth and survival, the implications to overall population rates of increase are less understood due to the large sample sizes needed to parameterize population models for all five juvenile life stages under multiple environmental and demographic conditions. Here, we present the results of >4,300 trials of wild-caught Aedes triseriatus (Say, 1823) larvae and pupae reared under varying resource quantity crossed by the presence or absence of competition within a single cohort as well as multiple overlapping cohorts. Demographic projection was used to make predictions of the realized growth rates of simulated Ae. triseriatus populations across the range of potential Ae. triseriatus fecundity. Further, to inform control efforts on juvenile habitat, we constructed a stochastic simulation to estimate the rates of successful emergence from habitats under different resource regimes and levels of cohort overlap. We found that while Ae. triseriatus populations were robust to low resource levels and competition within a cohort, the combination of these stressors with multiple cohort overlap led to self-limitation or complete collapse of mosquito populations. Despite this importance of intraspecific competition to population viability, the stochastic simulation revealed only a modest self-limitation of adult emergence, with the clear implication that high-resource habitats are a higher value control target. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Sun, Congcong; Wei, Lei; Luo, Feifei; Li, Yi; Li, Jiaobiao; Zhu, Feiqi; Kang, Ping; Xu, Rensi; Xiao, LuLu; Liu, Zhuolin; Xu, Pingyi
2012-01-01
Immune disorders may play an important role in the pathogenesis of Parkinson's disease (PD). Recently, polymorphisms in the HLA-DR region have been found to be associated with sporadic PD in European ancestry populations. However, polymorphisms in the HLA complex are highly variable with ethnic and geographic origin. To explore the relationships between polymorphisms of the HLA-DR region and sporadic PD in Chinese Han population, we genotyped 567 sporadic PD patients and 746 healthy controls in two independent series for the HLA-DRB1 locus with Polymerase chain reaction-sequence based typing(PCR-SBT). The χ2 test was used to evaluate the distribution of allele frequencies between the patients and healthy controls. The impact of HLA-DRB1 alleles on PD risk was estimated by unconditional logistic regression. We found a significant higher frequency of HLA-DRB1*0301 in sporadic PD patients than in healthy controls and a positive association, which was independent of onset age, between HLA-DRB1*0301 and PD risk. Conversely, a lower frequency of HLA-DRB1*0406 was found in sporadic PD patients than in healthy controls, with a negative association between HLA-DRB1*0406 and PD risk. Furthermore, a meta-analysis involving 195205 individuals was conducted to summarize the frequencies of these two alleles in populations from various ethnic regions, we found a higher frequency of HLA-DRB1*0301, but a lower frequency of HLA-DRB1*0406 in European ancestry populations than that in Asians, this was consistent with the higher prevalence of sporadic PD in European ancestry populations. Based on these results, we speculate that HLA-DRB1 alleles are associated with the susceptibility to sporadic PD in Chinese Han population, among them HLA-DRB1*0301 is a risk allele while the effect of HLA-DRB1*0406 deserves debate. PMID:23139797
2011-01-01
Background The relationship between asthma and traffic-related pollutants has received considerable attention. The use of individual-level exposure measures, such as residence location or proximity to emission sources, may avoid ecological biases. Method This study focused on the pediatric Medicaid population in Detroit, MI, a high-risk population for asthma-related events. A population-based matched case-control analysis was used to investigate associations between acute asthma outcomes and proximity of residence to major roads, including freeways. Asthma cases were identified as all children who made at least one asthma claim, including inpatient and emergency department visits, during the three-year study period, 2004-06. Individually matched controls were randomly selected from the rest of the Medicaid population on the basis of non-respiratory related illness. We used conditional logistic regression with distance as both categorical and continuous variables, and examined non-linear relationships with distance using polynomial splines. The conditional logistic regression models were then extended by considering multiple asthma states (based on the frequency of acute asthma outcomes) using polychotomous conditional logistic regression. Results Asthma events were associated with proximity to primary roads with an odds ratio of 0.97 (95% CI: 0.94, 0.99) for a 1 km increase in distance using conditional logistic regression, implying that asthma events are less likely as the distance between the residence and a primary road increases. Similar relationships and effect sizes were found using polychotomous conditional logistic regression. Another plausible exposure metric, a reduced form response surface model that represents atmospheric dispersion of pollutants from roads, was not associated under that exposure model. Conclusions There is moderately strong evidence of elevated risk of asthma close to major roads based on the results obtained in this population-based matched case-control study. PMID:21513554
ACSS2 gene variant associated with cleft lip and palate in two independent Hispanic populations.
Dodhia, Sonam; Celis, Katrina; Aylward, Alana; Cai, Yi; Fontana, Maria E; Trespalacios, Alberto; Hoffman, David C; Alfonso, Henry Ostos; Eisig, Sidney B; Su, Gloria H; Chung, Wendy K; Haddad, Joseph
2017-10-01
A candidate variant (p.Val496Ala) of the ACSS2 gene (T > C missense, rs59088485 variant at chr20: bp37 33509608) was previously found to consistently segregate with nonsyndromic cleft lip and/or palate (NSCLP) in three Honduran families. Objectives of this study were 1) to investigate the frequency of this ACSS2 variant in Honduran unrelated NSCLP patients and unrelated unaffected controls and 2) to investigate the frequency of this variant in Colombian unrelated affected NSCLP patients and unrelated unaffected controls. Case-control studies. Sanger sequencing of 99 unrelated Honduran NSCLP patients and 215 unrelated unaffected controls for the p.Val496Ala ACSS2 variant was used to determine the carrier frequency in NSCLP patients and controls. Sanger sequencing of 230 unrelated Colombian NSCLP patients and 146 unrelated unaffected controls for the p.Val496Ala ACSS2 variant was used to determine the carrier frequency in NSCLP patients and controls. In the Honduran population, the odds ratio of having NSCLP among carriers of the p.Val496Ala ACSS2 variant was 4.0 (P = .03), with a carrier frequency of seven of 99 (7.1%) in unrelated affected and four of 215 (1.9%) in unrelated unaffected individuals. In the Colombian population, the odds ratio of having NSCLP among carriers of the p.Val496Ala ACSS2 variant was 2.6 (P = .04), with a carrier frequency of 23 of 230 (10.0%) in unrelated affected and six of 146 (4.1%) in unrelated unaffected individuals. These findings support the role of ACSS2 in NSCLP in two independent Hispanic populations from Honduras and Colombia. NA Laryngoscope, 127:E336-E339, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.
Feliciangeli, M Dora; Mazzarri, Milena B; Campbell-Lendrum, Diarmid; Maroli, Michele; Maingon, Rhaiza
2003-01-01
An indoor vector control trial was carried out between December 1996 and February 1997, with the aim of reducing the population densities of Lutzomyia ovallesi, the proven vector of cutaneous leishmaniasis (CL) in El Ingenio, Miranda State, Venezuela. Houses were matched according to their structure ("bahareque" [mud and straw], concrete, and wood) and randomly assigned to a control group (n = 19) or a treated group (n = 20) that was sprayed with 25 mg/m(2) of lambdacyhalothrin. This dose was selected on the basis of a laboratory susceptibility test of Lu. ovallesi to pyrethroids. Sandfly abundance was measured using CDC light traps 7-79 d post-intervention, by which time the sandfly population in control houses had declined to very low levels, at what was the end of the transmission season. Catches of total females, fed females, and males were significantly lower in sprayed than in control houses immediately after treatment. Catches of total females and males in sprayed houses recovered, reaching the level of control houses after 7 and 11 weeks, respectively. Bioassays following WHO protocols using contact cones on a sandfly laboratory colony showed a short residual effect of the insecticide explaining these results. In contrast, there was no tendency for catches of fed females in the sprayed houses to recover during the course of the trial. Previous studies of adult population dynamics showed a short season of high abundance. Combined with these results, we believe that 2 indoor sprayings with lambdacyhalothrin, the first at the beginning of November and the second at the beginning of January, would considerably reduce the Lu. ovallesi population, and control CL transmission in this and other foci where this sandfly is considered to be the main vector.
Vleugels, Jasper L A; Sahin, Husna; Hazewinkel, Yark; Koens, Lianne; van den Berg, Jose G; van Leerdam, Monique E; Dekker, Evelien
2018-05-01
Carcinogenesis in Lynch syndrome involves fast progression of adenomas to colorectal cancer (CRC) because of microsatellite instability. The role of sessile serrated lesions (SSLs) and the serrated neoplasia pathway in these patients is unknown. The aim of this matched case-control study was to compare endoscopic detection rates and distribution of SSLs in Lynch syndrome patients with a matched control population. We collected data of Lynch syndrome patients with a proven germline mutation who underwent colonoscopy between January 2011 and April 2016 in 2 tertiary referral hospitals. Control subjects undergoing elective colonoscopy from 2011 and onward for symptoms or surveillance were selected from a prospectively collected database. Patients were matched 1:1 for age, gender, and index versus surveillance colonoscopy. An expert pathology review of serrated polyps was performed. The primary outcomes included the detection rates and distribution of SSLs. We identified 321 patients with Lynch syndrome who underwent at least 1 colonoscopy. Of these, 223 Lynch syndrome patients (mean age, 49.3; 59% women; index colonoscopy, 56%) were matched to 223 control subjects. SSLs were detected in 7.6% (95% confidence interval, 4.8-11.9) of colonoscopies performed in Lynch syndrome patients and in 6.7% (95% confidence interval, 4.1-10.8) of control subjects (P = .86). None of the detected SSLs in Lynch syndrome patients contained dysplasia. The detection rate of SSLs in Lynch syndrome patients undergoing colonoscopy is comparable with a matched population. These findings suggest that the role of the serrated neoplasia pathway in CRC development in Lynch syndrome seems to be comparable with that in the general population. Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.
O'Dwyer, Tom; O'Shea, Finbar; Wilson, Fiona
2015-11-01
The health benefits of physical activity (PA) in the general population are numerous; however, few studies have measured PA among adults with ankylosing spondylitis (AS). The aims of this study were to: (1) objectively measure the PA levels and cardiorespiratory fitness of adults with AS and compare these to population controls, and (2) examine the relationships between PA, cardiorespiratory function and condition-specific outcomes. This cross-sectional study included participants (>18 years) meeting the modified New York criteria for AS, and matched population controls. Exclusion criteria were the presence of comorbidities limiting PA, or recent changes in medication usage. Participants completed clinical questionnaires assessing disease activity, physical function and quality of life. Tri-axial accelerometers recorded habitual PA over 1 week. Cardiorespiratory fitness was assessed by submaximal treadmill test with breath-by-breath gas analysis and heart rate monitoring. Thirty-nine adults with AS and 39 controls were recruited. The AS group spent significantly less time performing vigorous-intensity PA than controls [mean difference (95 % CI) 1.8 min/day (1.2-2.7)] and performed significantly fewer bouts of health-enhancing PA [1.7 min/day (1.1-2.5)]. The AS group had significantly lower predicted VO(2MAX) than controls [6.0 mL kg(-1) min(-1) (1.8-10.1)]. PA was associated with aerobic capacity. Sedentary time was associated with disease activity and physical function. Adults with AS participate in less health-enhancing PA than population controls. Fewer than half meet PA recommendations, despite exercise being a key component of AS management. Explorations of PA behaviour and strategies to increase PA participation are needed.
Moseng, T; Tveter, A T; Holm, I; Dagfinrud, H
2014-12-01
To compare physical activity and physical fitness in patients with various musculoskeletal conditions receiving physiotherapy in primary care with population controls. Cross-sectional. One hundred and sixty-seven patients with musculoskeletal conditions receiving physiotherapy in primary care and 313 population controls from various settings and geographical areas. Physical activity was measured with the International Physical Activity Questionnaire short-form (IPAQ-sf) and reported in metabolic equivalents (METs). The 6-minute walk test and 30-second sit-to-stand test reflected cardiorespiratory endurance and muscular strength, respectively. Differences in physical activity between the groups were explored using the Mann-Whitney U-test. The patient group reported significantly less vigorous activity compared with the control group {median 0 [interquartile range (IQR) 0 to 960] vs median 240 [IQR 0 to 1440] MET minutes/week, respectively)} (P=0.001). A similar proportion of patients (68%) and controls (75%) reached the recommended level of health-enhancing physical activity (P=0.11). Linear regression analyses adjusted for age, body mass index and gender showed significantly poorer fitness in the patient group compared with the control group, reflected by the 6-minute walk test and the 30-second sit-to-stand test {mean difference 69m [95% confidence interval (CI) 52 to 85; P≤0.001] and six repetitions [95% CI 5 to 7; P≤0.001], respectively}. Patients with various long-term musculoskeletal conditions receiving physiotherapy in primary care had significantly poorer physical fitness and reported less vigorous physical activity compared with population controls. Copyright © 2014 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.
Collisional cascading - The limits of population growth in low earth orbit
NASA Technical Reports Server (NTRS)
Kessler, Donald J.
1991-01-01
Random collisions between made-made objects in earth orbit will lead to a significant source of orbital debris, but there are a number of uncertainties in these models, and additional analysis and data are required to fully characterize the future environment. However, the nature of these uncertainties are such that while the future environment is uncertain, the fact that collisions will control the future environment is less uncertain. The data that already exist is sufficient to show that cascading collisions will control the future debris environment with no, or very minor increases in the current low-earth-orbit population. Two populations control this process: explosion fragments and expended rocket bodies and payloads. Practices are already changing to limit explosions in low earth orbit; it is necessary to begin limiting the number of expended rocket bodies and payloads in orbit.
Havas, K A; Boone, R B; Hill, A E; Salman, M D
2014-06-01
Brucellosis has been reported in livestock and humans in the country of Georgia with Brucella melitensis as the most common species causing disease. Georgia lacked sufficient data to assess effectiveness of the various potential control measures utilizing a reliable population-based simulation model of animal-to-human transmission of this infection. Therefore, an agent-based model was built using data from previous studies to evaluate the effect of an animal-level infection control programme on human incidence and sheep flock and cattle herd prevalence of brucellosis in the Kakheti region of Georgia. This model simulated the patterns of interaction of human-animal workers, sheep flocks and cattle herds with various infection control measures and returned population-based data. The model simulates the use of control measures needed for herd and flock prevalence to fall below 2%. As per the model output, shepherds had the greatest disease reduction as a result of the infection control programme. Cattle had the greatest influence on the incidence of human disease. Control strategies should include all susceptible animal species, sheep and cattle, identify the species of brucellosis present in the cattle population and should be conducted at the municipality level. This approach can be considered as a model to other countries and regions when assessment of control strategies is needed but data are scattered. © 2013 Blackwell Verlag GmbH.
[Strengthen the cancer surveillance to promote cancer prevention and control in China].
He, J
2018-01-23
Cancer is a major chronic disease threatening the people's health in China. We reviewed the latest advances on cancer surveillance, prevention and control in our country, which may provide important clues for future cancer control. We used data from the National Central Cancer Registry, to describe and analyze the latest cancer statistics in China. We summarized updated informations on cancer control policies, conducting network, as well as programs in the country. We provided important suggestions on the future strategies of cancer prevention and control. The overall cancer burden in China has been increasing during the past decades. In 2014, there were about 3 804 000 new cancer cases and 2 296 000 cancer deaths in China. The age-standardized cancer incidence and mortality rates were 190.63/100 000 and 106.98/100 000, respectively. China has formed a comprehensive network on cancer prevention and control. Nationwide population-based cancer surveillance has been built up. The population coverage of cancer surveillance has been expanded, and the data quality has been improved. As the aging population is increasing and unhealthy life styles persist in our country, there will be an unnegligible cancer burden in China. Based on the comprehensive rationale of cancer control and prevention, National Cancer Center of China will perform its duty for future precise cancer control and prevention, based on cancer surveillance statistics.
Katju, Vaishali; Packard, Lucille B; Keightley, Peter D
2018-04-01
The consequences of mutations for population fitness depends on their individual selection coefficients and the effective population size. An earlier study of Caenorhabditis elegans spontaneous mutation accumulation lines evolved for 409 generations at three population sizes found that N e = 1 populations declined significantly in fitness whereas the fitness of larger populations (N e = 5, 50) was indistinguishable from the ancestral control under benign conditions. To test if larger MA populations harbor a load of cryptic deleterious mutations that are obscured under benign laboratory conditions, we measured fitness under osmotic stress via exposure to hypersaline conditions. The fitness of N e = 1 lines exhibited a further decline under osmotic stress compared to benign conditions. However, the fitness of larger populations remained indistinguishable from that of the ancestral control. The average effects of deleterious mutations in N e = 1 lines were estimated to be 22% for productivity and 14% for survivorship, exceeding values previously detected under benign conditions. Our results suggest that fitness decline is due to large effect mutations that are rapidly removed via selection even in small populations, with implications for conservation practices. Genetic stochasticity may not be as potent and immediate a threat to the persistence of small populations as other demographic and environmental stochastic factors. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.
[On the rational distribution of Chinese population].
Zhu, Z
1980-01-01
In 1949, the population distribution in China was characterized by the following distinct features. First, it was unbalanced, with high density in the eastern regions, in the plains, and in areas adjacent to railroads, river navigation routes and other transportation axes. Low population density was found in the western regions, mountainous regions, and areas far from transportation routes. Second, Hans were largest in number and distributed throughout the country, with major concentration in the eastern regions, while the minorities constituted about 10% of the total population and were distributed mainly in the far southwestern and northwestern areas. Third, over 89% of the 540 million of the population was distributed in rural areas while only about 10% in towns and cities, with high densities in some coastal cities. During the past 3 decades, the unbalanced nature of China's population has remained basically unchanged. This can be attributed to factors relating to natural conditions and resources, productivities, socioeconomic conditions, and technological development in different regions. In order to achieve a rational distribution of the Chinese population the following measures should be taken: 1) controlling the birth rate of the Hans and increasing the population of minorities; 2) moving the population of the dense areas to the border provinces in the western regions to develop their natural resources and to elevate the living standards; 3) modernizing the rural areas; 4) strictly controlling the industrial developments of large cities and their population growth; and 5) strictly restricting the unplanned migration of population to and from cities.
Regis, Lêda N.; Acioli, Ridelane Veiga; Silveira, José Constantino; Melo-Santos, Maria Alice Varjal; Souza, Wayner Vieira; Ribeiro, Cândida M. Nogueira.; da Silva, Juliana C. Serafim.; Monteiro, Antonio Miguel Vieira; Oliveira, Cláudia M. F.; Barbosa, Rosângela M. R.; Braga, Cynthia; Rodrigues, Marco Aurélio Benedetti; Silva, Marilú Gomes N. M.; Ribeiro Jr., Paulo Justiniano; Bonat, Wagner Hugo; de Castro Medeiros, Liliam César; Carvalho, Marilia Sa; Furtado, André Freire
2013-01-01
Aedes aegypti has developed evolution-driven adaptations for surviving in the domestic human habitat. Several trap models have been designed considering these strategies and tested for monitoring this efficient vector of Dengue. Here, we report a real-scale evaluation of a system for monitoring and controlling mosquito populations based on egg sampling coupled with geographic information systems technology. The SMCP-Aedes, a system based on open technology and open data standards, was set up from March/2008 to October/2011 as a pilot trial in two sites of Pernambuco -Brazil: Ipojuca (10,000 residents) and Santa Cruz (83,000), in a joint effort of health authorities and staff, and a network of scientists providing scientific support. A widespread infestation by Aedes was found in both sites in 2008–2009, with 96.8%–100% trap positivity. Egg densities were markedly higher in SCC than in Ipojuca. A 90% decrease in egg density was recorded in SCC after two years of sustained control pressure imposed by suppression of >7,500,000 eggs and >3,200 adults, plus larval control by adding fishes to cisterns. In Ipojuca, 1.1 million mosquito eggs were suppressed and a 77% reduction in egg density was achieved. This study aimed at assessing the applicability of a system using GIS and spatial statistic analysis tools for quantitative assessment of mosquito populations. It also provided useful information on the requirements for reducing well-established mosquito populations. Results from two cities led us to conclude that the success in markedly reducing an Aedes population required the appropriate choice of control measures for sustained mass elimination guided by a user-friendly mosquito surveillance system. The system was able to support interventional decisions and to assess the program’s success. Additionally, it created a stimulating environment for health staff and residents, which had a positive impact on their commitment to the dengue control program. PMID:23844059
Tanaka, Cinthia Marie; Iwasa, Yoh
2012-09-21
We develop a simple cultural dynamics model to dicuss the spread of the hinoeuma superstition in Japan. A large drop in the number of newborn babies observed in 1966 was attributed mainly to parents' avoiding having a child born in a hinoeuma year. Presumably, Japanese parents were afraid that a daughter born in 1966 (a hinoeuma year) might later have difficulty finding a mate. We construct mathematical models to examine whether the hinoeuma superstition would likely become extinct or be stably maintained in the population. We classify members of a population according to whether they believed the hinoeuma superstition (believer or nonbeliever), their gender (male or female), and their year of birth (born in a hinoeuma year or not). We compare several cases that differ according to (1) whether the belief in the superstition was transmitted to children by matrilineal, patrilineal, or Mendelian inheritance; (2) which parent controlled the timing of pregnancy and childbirth (maternal or paternal birth control); and (3) the probability of birth control failure. Our results show that the hinoeuma superstition is likely to spread if the mother has a strong influence on birth control and on the belief of their children. In contrast, if birth control is paternal and the belief is passed down from father to child, the hinoeuma superstition is likely to become extinct. In between these extremes, whether the superstition becomes extinct or fixed in the population depends on the initial frequency of believers in the population. Copyright © 2012 Elsevier Ltd. All rights reserved.
Digitoxin medication and cancer; case control and internal dose-response studies
Haux, Johan; Klepp, Olbjørn; Spigset, Olav; Tretli, Steinar
2001-01-01
Background Digitoxin induces apoptosis in different human malignant cell lines in vitro. In this paper we investigated if patients taking digitoxin for cardiac disease have a different cancer incidence compared to the general population. Methods Computer stored data on digitoxin concentrations in plasma from 9271 patients with cardiac disease were used to define a user population. Age and sex matched controls from the Norwegian Cancer Registry were used to calculate the number of expected cancer cases. Results The population on digitoxin showed a higher incidence of cancer compared to the control population. However, an additional analysis showed that the population on digitoxin had a general increased risk of cancer already, before the start on digitoxin. Leukemia/lymphoma were the cancer types which stood out with the highest risk in the digitoxin population before starting on digitoxin. This indicates that yet unknown risk factors exist for cardiovascular disease and lymphoproliferative cancer. An internal dose-response analysis revealed a relationship between high plasma concentration of digitoxin and a lower risk for leukemia/lymphoma and for cancer of the kidney/urinary tract. Conclusion Morbidity and mortality are high in the population on digitoxin, due to high age and cardiac disease.These factors disturb efforts to isolate an eventual anticancer effect of digitoxin in this setting. Still, the results may indicate an anticancer effect of digitoxin for leukemia/lymphoma and kidney/urinary tract cancers. Prospective clinical cancer trials have to be done to find out if digitoxin and other cardiac glycosides are useful as anticancer agents. PMID:11532201
Overall mortality among patients surviving an episode of peptic ulcer bleeding
Ruigomez, A.; Rodriguez, L. A.; Hasselgren, G.; Johansson, S.; Wallander, M.
2000-01-01
STUDY OBJECTIVE—The authors investigated whether patients who have survived an acute episode of peptic ulcer bleeding (PUB) have an excess long term all cause mortality compared with the general population free of PUB. DESIGN—Follow up study of previously identified cohort of patients with a PUB episode and a general population cohort. SETTING—The source population included all people aged 30 to 89 years, registered with general practitioners in the United Kingdom. PATIENTS—All patients alive one month after the PUB episode constituted the cohort of PUB patients (n=978). A control group of 5000 people was randomly sampled from the source population. The same eligibility criteria as for patients with PUB were applied to the control series. Also, controls had to be free of PUB before start date. MAIN RESULTS—Relative risk of mortality among PUB patients was 2.1, 95%CI: 1.7, 2.6) compared with the general population. This increased mortality risk occurred mainly in the patients less than 60 years old. No difference was observed between men and women. The excess mortality was not only circumscribed to deaths attributable to recurrent gastrointestinal bleed, but also cardiovascular, cancer and other causes. CONCLUSIONS—People who have survived an acute episode of PUB have a reduced long term survival compared with the general population.This reduction was stronger among middle age patients than in the elderly. Keywords: cohort study; mortality; peptic ulcer; bleeding; population-based study PMID:10715746
Winney, Bruce; Boumertit, Abdelhamid; Day, Tammy; Davison, Dan; Echeta, Chikodi; Evseeva, Irina; Hutnik, Katarzyna; Leslie, Stephen; Nicodemus, Kristin; Royrvik, Ellen C; Tonks, Susan; Yang, Xiaofeng; Cheshire, James; Longley, Paul; Mateos, Pablo; Groom, Alexandra; Relton, Caroline; Bishop, D Tim; Black, Kathryn; Northwood, Emma; Parkinson, Louise; Frayling, Timothy M; Steele, Anna; Sampson, Julian R; King, Turi; Dixon, Ron; Middleton, Derek; Jennings, Barbara; Bowden, Rory; Donnelly, Peter; Bodmer, Walter
2012-01-01
There is a great deal of interest in a fine-scale population structure in the UK, both as a signature of historical immigration events and because of the effect population structure may have on disease association studies. Although population structure appears to have a minor impact on the current generation of genome-wide association studies, it is likely to have a significant part in the next generation of studies designed to search for rare variants. A powerful way of detecting such structure is to control and document carefully the provenance of the samples involved. In this study, we describe the collection of a cohort of rural UK samples (The People of the British Isles), aimed at providing a well-characterised UK-control population that can be used as a resource by the research community, as well as providing a fine-scale genetic information on the British population. So far, some 4000 samples have been collected, the majority of which fit the criteria of coming from a rural area and having all four grandparents from approximately the same area. Analysis of the first 3865 samples that have been geocoded indicates that 75% have a mean distance between grandparental places of birth of 37.3 km, and that about 70% of grandparental places of birth can be classed as rural. Preliminary genotyping of 1057 samples demonstrates the value of these samples for investigating a fine-scale population structure within the UK, and shows how this can be enhanced by the use of surnames. PMID:21829225
Winney, Bruce; Boumertit, Abdelhamid; Day, Tammy; Davison, Dan; Echeta, Chikodi; Evseeva, Irina; Hutnik, Katarzyna; Leslie, Stephen; Nicodemus, Kristin; Royrvik, Ellen C; Tonks, Susan; Yang, Xiaofeng; Cheshire, James; Longley, Paul; Mateos, Pablo; Groom, Alexandra; Relton, Caroline; Bishop, D Tim; Black, Kathryn; Northwood, Emma; Parkinson, Louise; Frayling, Timothy M; Steele, Anna; Sampson, Julian R; King, Turi; Dixon, Ron; Middleton, Derek; Jennings, Barbara; Bowden, Rory; Donnelly, Peter; Bodmer, Walter
2012-02-01
There is a great deal of interest in a fine-scale population structure in the UK, both as a signature of historical immigration events and because of the effect population structure may have on disease association studies. Although population structure appears to have a minor impact on the current generation of genome-wide association studies, it is likely to have a significant part in the next generation of studies designed to search for rare variants. A powerful way of detecting such structure is to control and document carefully the provenance of the samples involved. In this study, we describe the collection of a cohort of rural UK samples (The People of the British Isles), aimed at providing a well-characterised UK-control population that can be used as a resource by the research community, as well as providing a fine-scale genetic information on the British population. So far, some 4000 samples have been collected, the majority of which fit the criteria of coming from a rural area and having all four grandparents from approximately the same area. Analysis of the first 3865 samples that have been geocoded indicates that 75% have a mean distance between grandparental places of birth of 37.3 km, and that about 70% of grandparental places of birth can be classed as rural. Preliminary genotyping of 1057 samples demonstrates the value of these samples for investigating a fine-scale population structure within the UK, and shows how this can be enhanced by the use of surnames.
Marini, Lorenzo; Baseggio, Alberto; Drago, Andrea; Martini, Simone; Manella, Paolo; Romi, Roberto; Mazzon, Luca
2015-01-01
After its first introduction in the 1980's the Asian tiger mosquito, Aedes albopictus (Skuse), has spread throughout Southern Europe. Ae. albopictus is considered an epidemiologically important vector for the transmission of many viral pathogens such as the yellow fever virus, dengue fever and Chikungunya fever, as well as several filarial nematodes such as Dirofilaria immitis or D. repens. It is therefore crucial to develop measures to reduce the risks of disease transmission by controlling the vector populations. The aim of the study was to compare the efficacy of two application techniques (mist vs. stretcher sprayer) and two insecticides (Etox based on the nonester pyrethroid Etofenprox vs. Microsin based on the pyrethroid type II Cypermetrin) in controlling adult tiger mosquito populations in highly populated areas. To test the effect of the two treatments pre- and post-treatment human landing rate counts were conducted for two years. After one day from the treatment we observed a 100% population decrease in mosquito abundance with both application methods and both insecticides. However, seven and 14 days after the application the stretcher sprayer showed larger population reductions than the mist sprayer. No effect of insecticide type after one day and 14 days was found, while Etox caused slightly higher population reduction than Microsin after seven days. Emergency measures to locally reduce the vector populations should adopt adulticide treatments using stretcher sprayers. However, more research is still needed to evaluate the potential negative effects of adulticide applications on non-target organisms.
Harold R. Offord
1966-01-01
Sequential sampling based on a negative binomial distribution of ribes populations required less than half the time taken by regular systematic line transect sampling in a comparison test. It gave the same control decision as the regular method in 9 of 13 field trials. A computer program that permits sequential plans to be built readily for other white pine regions is...
ERIC Educational Resources Information Center
Kirby, A.; Woodward, A.; Jackson, S.; Wang, Y.; Crawford, M. A.
2010-01-01
Despite the increased interest in the effects of omega-3 supplementation on childrens' learning and behaviour, there are a lack of controlled studies of this kind that have utilised a typically developing population. This study investigated the effects of omega-3 supplementation in 450 children aged 8-10 years old from a mainstream school…