REVIEWS OF TOPICAL PROBLEMS: Population synthesis in astrophysics
NASA Astrophysics Data System (ADS)
Popov, S. B.; Prokhorov, M. E.
2007-11-01
Population synthesis is a method for numerical simulation of the population of objects with a complex evolution. This method is widely used in astrophysics. We consider its main applications to studying astronomical objects. Examples of modeling evolution are given for populations of close binaries and isolated neutron stars. The application of the method to studying active galactic nuclei and the integral spectral characteristics of galaxies is briefly discussed. An extensive bibliography on all the topics covered is provided.
Lin, S; Melendez-Torres, G J
2017-10-01
To systematically review studies of TB treatment experiences in immigrant populations, using Critical Interpretive Synthesis (CIS). On 26 October 2014, MEDLINE, CINAHL, Embase, LILACS, and PsycINFO were systematically searched. Grey literature and reference lists were hand-searched. Initial papers included were restricted to studies of immigrant patient perspectives; after a model was developed, a second set of papers was included to test the emerging theory. Of 1761 studies identified in the search, a total of 29 were included in the synthesis. Using those studies, we developed a model that suggested treatment experiences were strongly related to the way both individuals and societies adjusted to immigration ('acculturation strategies'). Relationships with healthcare workers and immigration policies played particularly significant roles in TB treatment. This review emphasised the roles of repatriation policy and healthcare workers in forming experiences of TB treatment in immigrant populations. © 2017 John Wiley & Sons Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chung, Chul; Yoon, Suk-Jin; Lee, Young-Wook, E-mail: chulchung@yonsei.ac.kr, E-mail: sjyoon0691@yonsei.ac.kr
The discovery of multiple stellar populations in Milky Way globular clusters (GCs) has stimulated various follow-up studies on helium-enhanced stellar populations. Here we present the evolutionary population synthesis models for the spectro-photometric evolution of simple stellar populations (SSPs) with varying initial helium abundance ( Y {sub ini}). We show that Y {sub ini} brings about dramatic changes in spectro-photometric properties of SSPs. Like the normal-helium SSPs, the integrated spectro-photometric evolution of helium-enhanced SSPs is also dependent on metallicity and age for a given Y {sub ini}. We discuss the implications and prospects for the helium-enhanced populations in relation to themore » second-generation populations found in the Milky Way GCs. All of the models are available at http://web.yonsei.ac.kr/cosmic/data/YEPS.htm.« less
An isochrone data base and a rapid model for stellar population synthesis
NASA Astrophysics Data System (ADS)
Li, Zhongmu; Han, Zhanwen
2008-06-01
We first presented an isochrone data base that can be widely used for stellar population synthesis studies and colour-magnitude diagram (CMD) fitting. The data base consists of the isochrones of both single-star and binary-star simple stellar populations (ss-SSPs and bs-SSPs). The ranges for the age and metallicity of populations are 0-15 Gyr and 0.0001-0.03, respectively. All data are available for populations with two widely used initial mass functions (IMFs), that is, Salpeter IMF and Chabrier IMF. The uncertainty caused by the data base (about 0.81 per cent) is designed to be smaller than those caused by the Hurley code and widely used stellar spectra libraries (e.g. BaSeL 3.1) when it is used for stellar population synthesis. Based on the isochrone data base, we then built a rapid stellar population synthesis (RPS) model and calculated the high-resolution (0.3-Å) integrated spectral energy distributions, Lick indices and colour indices for bs-SSPs and ss-SSPs. In particular, we calculated the UBVRIJHKLM colours, ugriz colours and some composite colours that consist of magnitudes on different systems. These colours are useful for disentangling the well-known stellar age-metallicity degeneracy according to our previous work. As an example for applying the isochrone data base for CMD fitting, we fitted the CMDs of two star clusters (M67 and NGC1868) and obtained their distance moduli, colour excesses, stellar metallicities and ages. The results showed that the isochrones of bs-SSPs are closer to those of real star clusters. It suggests that we should take the effects of binary interactions into account in stellar population synthesis. We also discussed on the limitations of the application of the isochrone data base and the results of the RPS model. All the data are available at the CDS or on request to the authors. E-mail: zhongmu.li@gmail.com
Probing evolutionary population synthesis models in the near infrared with early-type galaxies
NASA Astrophysics Data System (ADS)
Dahmer-Hahn, Luis Gabriel; Riffel, Rogério; Rodríguez-Ardila, Alberto; Martins, Lucimara P.; Kehrig, Carolina; Heckman, Timothy M.; Pastoriza, Miriani G.; Dametto, Natacha Z.
2018-06-01
We performed a near-infrared (NIR; ˜1.0 -2.4 μm) stellar population study in a sample of early-type galaxies. The synthesis was performed using five different evolutionary population synthesis libraries of models. Our main results can be summarized as follows: low-spectral-resolution libraries are not able to produce reliable results when applied to the NIR alone, with each library finding a different dominant population. The two newest higher resolution models, on the other hand, perform considerably better, finding consistent results to each other and to literature values. We also found that optical results are consistent with each other even for lower resolution models. We also compared optical and NIR results and found out that lower resolution models tend to disagree in the optical and in the NIR, with higher fraction of young populations in the NIR and dust extinction ˜1 mag higher than optical values. For higher resolution models, optical and NIR results tend to agree much better, suggesting that a higher spectral resolution is fundamental to improve the quality of the results.
O'Malley, Maureen A
2018-06-01
Since the 1940s, microbiologists, biochemists and population geneticists have experimented with the genetic mechanisms of microorganisms in order to investigate evolutionary processes. These evolutionary studies of bacteria and other microorganisms gained some recognition from the standard-bearers of the modern synthesis of evolutionary biology, especially Theodosius Dobzhansky and Ledyard Stebbins. A further period of post-synthesis bacterial evolutionary research occurred between the 1950s and 1980s. These experimental analyses focused on the evolution of population and genetic structure, the adaptive gain of new functions, and the evolutionary consequences of competition dynamics. This large body of research aimed to make evolutionary theory testable and predictive, by giving it mechanistic underpinnings. Although evolutionary microbiologists promoted bacterial experiments as methodologically advantageous and a source of general insight into evolution, they also acknowledged the biological differences of bacteria. My historical overview concludes with reflections on what bacterial evolutionary research achieved in this period, and its implications for the still-developing modern synthesis.
Stellar Populations in BL Lac type Objects
NASA Astrophysics Data System (ADS)
Serote Roos, Margarida
The relationship between an Active Galactic Nucleus (AGN) and its host galaxy is a crucial question in the study of galaxy evolution. We present an estimate of the stellar contribution in a sample of low luminosity BL Lac type objects. We have performed stellar population synthesis for a sample of 19 objects selected from Marchã et al. (1996, MNRAS 281, 425). The stellar content is quantified using the equivalent widths of all absorption features available throughout the spectrum. The synthesis is done by a variant of the GPG method (Pelat: 1997, MNRAS 284, 365).
Multiplex sequencing of plant chloroplast genomes using Solexa sequencing-by-synthesis technology
Richard Cronn; Aaron Liston; Matthew Parks; David S. Gernandt; Rongkun Shen; Todd Mockler
2008-01-01
Organellar DNA sequences are widely used in evolutionary and population genetic studies; however, the conservative nature of chloroplast gene and genome evolution often limits phylogenetic resolution and statistical power. To gain maximal access to the historical record contained within chloroplast genomes, we have adapted multiplex sequencing-by-synthesis (MSBS) to...
USDA-ARS?s Scientific Manuscript database
Periodic sampling of 43 independent monitors, initially active with Formosan subterranean termite, Coptotermes formosanus Shiraki, or the eastern subterranean termite, Reticulitermes flavipes (Kollar) was conducted to evaluate the effects of cellulose baits containing one of three chitin synthesis i...
Biofield therapies: helpful or full of hype? A best evidence synthesis.
Jain, Shamini; Mills, Paul J
2010-03-01
Biofield therapies (such as Reiki, therapeutic touch, and healing touch) are complementary medicine modalities that remain controversial and are utilized by a significant number of patients, with little information regarding their efficacy. This systematic review examines 66 clinical studies with a variety of biofield therapies in different patient populations. We conducted a quality assessment as well as a best evidence synthesis approach to examine evidence for biofield therapies in relevant outcomes for different clinical populations. Studies overall are of medium quality, and generally meet minimum standards for validity of inferences. Biofield therapies show strong evidence for reducing pain intensity in pain populations, and moderate evidence for reducing pain intensity hospitalized and cancer populations. There is moderate evidence for decreasing negative behavioral symptoms in dementia and moderate evidence for decreasing anxiety for hospitalized populations. There is equivocal evidence for biofield therapies' effects on fatigue and quality of life for cancer patients, as well as for comprehensive pain outcomes and affect in pain patients, and for decreasing anxiety in cardiovascular patients. There is a need for further high-quality studies in this area. Implications and future research directions are discussed.
Brodsky, V Y; Malchenko, L A; Konchenko, D S; Zvezdina, N D; Dubovaya, T K
2016-08-01
Primary cultures of rat hepatocytes were studied in serum-free media. Ultradian protein synthesis rhythm was used as a marker of cell synchronization in the population. Addition of glutamic acid (0.2 mg/ml) to the medium of nonsynchronous sparse cultures resulted in detection of a common protein synthesis rhythm, hence in synchronization of the cells. The antagonist of glutamic acid metabotropic receptors MCPG (0.01 mg/ml) added together with glutamic acid abolished the synchronization effect; in sparse cultures, no rhythm was detected. Feeding rats with glutamic acid (30 mg with food) resulted in protein synthesis rhythm in sparse cultures obtained from the rats. After feeding without glutamic acid, linear kinetics of protein synthesis was revealed. Thus, glutamic acid, a component of blood as a non-neural transmitter, can synchronize the activity of hepatocytes and can form common rhythm of protein synthesis in vitro and in vivo. This effect is realized via receptors. Mechanisms of cell-cell communication are discussed on analyzing effects of non-neural functions of neurotransmitters. Glutamic acid is used clinically in humans. Hence, a previously unknown function of this drug is revealed.
Cerca, Nuno; Martins, Silvia; Cerca, Filipe; Jefferson, Kimberly K; Pier, Gerald B; Oliveira, Rosário; Azeredo, Joana
2005-08-01
To quantitatively compare the antibiotic susceptibility of biofilms formed by the coagulase-negative staphylococci (CoNS) Staphylococcus epidermidis and Staphylococcus haemolyticus with the susceptibility of planktonic cultures. Several CoNS strains were grown planktonically or as biofilms to determine the effect of the mode of growth on the level of susceptibility to antibiotics with different mechanisms of action. The utility of a new, rapid colorimetric method that is based on the reduction of a tetrazolium salt (XTT) to measure cell viability was tested by comparison with standard bacterial enumeration techniques. A 6 h kinetic study was performed using dicloxacillin, cefazolin, vancomycin, tetracycline and rifampicin at the peak serum concentration of each antibiotic. In planktonic cells, inhibitors of cell wall synthesis were highly effective over a 3 h period. Biofilms were much less susceptible than planktonic cultures to all antibiotics tested, particularly inhibitors of cell wall synthesis. The susceptibility to inhibitors of protein and RNA synthesis was affected by the biofilm phenotype to a lesser degree. Standard bacterial enumeration techniques and the XTT method produced equivalent results both in biofilms and planktonic assays. This study provides a more accurate comparison between the antibiotic susceptibilities of planktonic versus biofilm populations, because the cell densities in the two populations were similar and because we measured the concentration required to inhibit bacterial metabolism rather than to eradicate the entire bacterial population. While the biofilm phenotype is highly resistant to antibiotics that target cell wall synthesis, it is fairly susceptible to antibiotics that target RNA and protein synthesis.
NASA Astrophysics Data System (ADS)
Eldridge, J. J.; Stanway, E. R.; Xiao, L.; McClelland, L. A. S.; Taylor, G.; Ng, M.; Greis, S. M. L.; Bray, J. C.
2017-11-01
The Binary Population and Spectral Synthesis suite of binary stellar evolution models and synthetic stellar populations provides a framework for the physically motivated analysis of both the integrated light from distant stellar populations and the detailed properties of those nearby. We present a new version 2.1 data release of these models, detailing the methodology by which Binary Population and Spectral Synthesis incorporates binary mass transfer and its effect on stellar evolution pathways, as well as the construction of simple stellar populations. We demonstrate key tests of the latest Binary Population and Spectral Synthesis model suite demonstrating its ability to reproduce the colours and derived properties of resolved stellar populations, including well-constrained eclipsing binaries. We consider observational constraints on the ratio of massive star types and the distribution of stellar remnant masses. We describe the identification of supernova progenitors in our models, and demonstrate a good agreement to the properties of observed progenitors. We also test our models against photometric and spectroscopic observations of unresolved stellar populations, both in the local and distant Universe, finding that binary models provide a self-consistent explanation for observed galaxy properties across a broad redshift range. Finally, we carefully describe the limitations of our models, and areas where we expect to see significant improvement in future versions.
ERIC Educational Resources Information Center
Fadale, LaVerna M.; Winter, Gene M.
The Two-Year College Development Center undertook a project to identify two-year college programs in New York State that successfully serve one or more of the special needs populations targeted by the Carl D. Perkins Act. Four special needs populations were targeted for in-depth study: single parents/homemakers, learning disabled, limited English…
NASA Astrophysics Data System (ADS)
Ronco, M. P.; Guilera, O. M.; de Elía, G. C.
2017-11-01
Population synthesis models of planetary systems developed during the last ˜15 yr could reproduce several of the observables of the exoplanet population, and also allowed us to constrain planetary formation models. We present our planet formation model, which calculates the evolution of a planetary system during the gaseous phase. The code incorporates relevant physical phenomena for the formation of a planetary system, like photoevaporation, planet migration, gas accretion, water delivery in embryos and planetesimals, a detailed study of the orbital evolution of the planetesimal population, and the treatment of the fusion between embryos, considering their atmospheres. The main goal of this work, unlike other works of planetary population synthesis, is to find suitable scenarios and physical parameters of the disc to form Solar system analogues. We are specially interested in the final planet distributions, and in the final surface density, eccentricity and inclination profiles for the planetesimal population. These final distributions will be used as initial conditions for N-body simulations to study the post-oligarchic formation in a second work. We then consider different formation scenarios, with different planetesimal sizes and different type I migration rates. We find that Solar system analogues are favoured in massive discs, with low type I migration rates, and small planetesimal sizes. Besides, those rocky planets within their habitables zones are dry when discs dissipate. At last, the final configurations of Solar system analogues include information about the mass and semimajor axis of the planets, water contents, and the properties of the planetesimal remnants.
NASA Astrophysics Data System (ADS)
Goudfrooij, Paul
2009-07-01
Much current research in cosmology and galaxy formation relies on an accurate interpretation of colors of galaxies in terms of their evolutionary state, i.e., in terms of ages and metallicities. One particularly important topic is the ability to identify early-type galaxies at "intermediate" ages { 500 Myr - 5 Gyr}, i.e., the period between the end of star formation and half the age of the universe. Currently, integrated-light studies must rely on population synthesis models which rest upon spectral libraries of stars in the solar neighborhood. These models have a difficult time correctly incorporating short-lived evolutionary phases such as thermally pulsing AGB stars, which produce up to 80% of the flux in the near-IR in this age range. Furthermore, intermediate-age star clusters in the Local Group do not represent proper templates against which to calibrate population synthesis models in this age range, because their masses are too low to render the effect of stochastic fluctuations due to the number of bright RGB and AGB stars negligible. As a consequence, current population synthesis models have trouble reconciling the evolutionary state of high-redshift galaxies from optical versus near-IR colors. We propose a simple and effective solution to this issue, namely obtaining high-quality EMPIRICAL colors of massive globular clusters in galaxy merger remnants which span this important age range. These colors should serve as relevant references, both to identify intermediate-age objects in the local and distant universe and as calibrators for population synthesis modellers.
ERIC Educational Resources Information Center
Mathews-Aydinli, Julie
2008-01-01
This article provides a synthesis and review of 41 recent research studies focusing on the population of adult English language learners (ELLs) studying in nonacademic contexts. It notes the unique qualities and importance of understanding the English-language needs of this population, provides a critical overview of the existing literature, and…
A Population Synthesis Study of Terrestrial Gamma-ray Flashes
NASA Astrophysics Data System (ADS)
Cramer, E. S.; Briggs, M. S.; Stanbro, M.; Dwyer, J. R.; Mailyan, B. G.; Roberts, O.
2017-12-01
In astrophysics, population synthesis models are tools used to determine what mix of stars could be consistent with the observations, e.g. how the intrinsic mass-to-light ratio changes by the measurement process. A similar technique could be used to understand the production of TGFs. The models used for this type of population study probe the conditions of electron acceleration inside the high electric field regions of thunderstorms, i.e. acceleration length, electric field strength, and beaming angles. In this work, we use a Monte Carlo code to generate bremsstrahlung photons from relativistic electrons that are accelerated by a large-scale RREA thunderstorm electric field. The code simulates the propagation of photons through the atmosphere at various source altitudes, where they interact with air via Compton scattering, pair production, and photoelectric absorption. We then show the differences in the hardness ratio at spacecraft altitude between these different simulations and compare them with TGF data from Fermi-GBM. Such comparisons can lead to constraints that can be applied to popular TGF beaming models, and help determine whether the population presented in this study is consistent or not with reality.
Cerca, Nuno; Martins, Silvia; Cerca, Filipe; Jefferson, Kimberly K.; Pier, Gerald B.; Oliveira, Rosário; Azeredo, Joana
2005-01-01
Objectives To quantitatively compare the antibiotic susceptibility of biofilms formed by the coagulase-negative staphylococci (CoNS) Staphylococcus epidermidis and Staphylococcus haemolyticus with the susceptibility of planktonic cultures. Methods Several CoNS strains were grown planktonically or as biofilms to determine the effect of the mode of growth on the level of susceptibility to antibiotics with different mechanisms of action. The utility of a new, rapid colorimetric method that is based on the reduction of a tetrazolium salt (XTT) to measure cell viability was tested by comparison with standard bacterial enumeration techniques. A 6 h kinetic study was performed using dicloxacillin, cefazolin, vancomycin, tetracycline and rifampicin at the peak serum concentration of each antibiotic. Results In planktonic cells, inhibitors of cell wall synthesis were highly effective over a 3 h period. Biofilms were much less susceptible than planktonic cultures to all antibiotics tested, particularly inhibitors of cell wall synthesis. The susceptibility to inhibitors of protein and RNA synthesis was affected by the biofilm phenotype to a lesser degree. Standard bacterial enumeration techniques and the XTT method produced equivalent results both in biofilms and planktonic assays. Conclusions This study provides a more accurate comparison between the antibiotic susceptibilities of planktonic versus biofilm populations, because the cell densities in the two populations were similar and because we measured the concentration required to inhibit bacterial metabolism rather than to eradicate the entire bacterial population. While the biofilm phenotype is highly resistant to antibiotics that target cell wall synthesis, it is fairly susceptible to antibiotics that target RNA and protein synthesis. PMID:15980094
POPCORN: A comparison of binary population synthesis codes
NASA Astrophysics Data System (ADS)
Claeys, J. S. W.; Toonen, S.; Mennekens, N.
2013-01-01
We compare the results of three binary population synthesis codes to understand the differences in their results. As a first result we find that when equalizing the assumptions the results are similar. The main differences arise from deviating physical input.
The Occurence of Nuclear Starbursts in Seyfert 1 Galaxies
NASA Astrophysics Data System (ADS)
Schinnerer, E.; Colbert, E.; Armus, L.; Scoville, N. Z.
2001-05-01
Medium resolution H and K band spectra with high angular reesolution were obtained for a small sample of nearby Seyfert galaxies using NIRSPEC at the Keck telescope. Recent studies with medium resolution have found evidence for a lack of powerful starbursts in Seyfert1 galaxies. Differences between the two Seyfert types might provide a challenge for the unified scheme proposed for Seyfert galaxies. A preliminary analysis indicates that most of the Seyfert1 galaxies do indeed show signs of circumnuclar star formation. Detailed modelling using population synthesis in conjunction with NIR spectral synthesis will allow to estimate the age, star formation history and mass of these stellar population.
Selective memory generalization by spatial patterning of protein synthesis
O’Donnell, Cian; Sejnowski, Terrence J.
2014-01-01
Summary Protein synthesis is crucial for both persistent synaptic plasticity and long-term memory. De novo protein expression can be restricted to specific neurons within a population, and to specific dendrites within a single neuron. Despite its ubiquity, the functional benefits of spatial protein regulation for learning are unknown. We used computational modeling to study this problem. We found that spatially patterned protein synthesis can enable selective consolidation of some memories but forgetting of others, even for simultaneous events that are represented by the same neural population. Key factors regulating selectivity include the functional clustering of synapses on dendrites, and the sparsity and overlap of neural activity patterns at the circuit level. Based on these findings we proposed a novel two-step model for selective memory generalization during REM and slow-wave sleep. The pattern-matching framework we propose may be broadly applicable to spatial protein signaling throughout cortex and hippocampus. PMID:24742462
Selective memory generalization by spatial patterning of protein synthesis.
O'Donnell, Cian; Sejnowski, Terrence J
2014-04-16
Protein synthesis is crucial for both persistent synaptic plasticity and long-term memory. De novo protein expression can be restricted to specific neurons within a population, and to specific dendrites within a single neuron. Despite its ubiquity, the functional benefits of spatial protein regulation for learning are unknown. We used computational modeling to study this problem. We found that spatially patterned protein synthesis can enable selective consolidation of some memories but forgetting of others, even for simultaneous events that are represented by the same neural population. Key factors regulating selectivity include the functional clustering of synapses on dendrites, and the sparsity and overlap of neural activity patterns at the circuit level. Based on these findings, we proposed a two-step model for selective memory generalization during REM and slow-wave sleep. The pattern-matching framework we propose may be broadly applicable to spatial protein signaling throughout cortex and hippocampus. Copyright © 2014 Elsevier Inc. All rights reserved.
Fitzgerald, Niamh; Angus, Kathryn; Emslie, Carol; Shipton, Deborah; Bauld, Linda
2016-10-01
Consistent review-level evidence supports the effectiveness of population-level alcohol policies in reducing alcohol-related harms. Such policies interact with well-established social, cultural and biological differences in how men and women perceive, relate to and use alcohol, and with wider inequalities, in ways which may give rise to gender differences in policy effectiveness. This paper aimed to examine the extent to which gender-specific data and analyses were considered in, and are available from, systematic reviews of population-level alcohol policy interventions, and where possible, to conduct a narrative synthesis of relevant data. A prior systematic 'review of reviews' of population level alcohol interventions 2002-2012 was updated to May 2014, all gender-relevant data extracted, and the level and quality of gender reporting assessed. A narrative synthesis of extracted findings was conducted. Sixty-three systematic reviews, covering ten policy areas, were included. Five reviews (8%) consistently provided information on baseline participation by gender for each individual study in the review and twenty-nine (46%) reported some gender-specific information on the impact of the policies under consideration. Specific findings include evidence of possible gender differences in the impact of and exposure to alcohol marketing, and a failure to consider potential unintended consequences and harm to others in most reviews. Gender is poorly reported in systematic reviews of population-level interventions to reduce alcohol-related harm, hindering assessment of the intended and unintended effects of such policies on women and men. © 2016 Society for the Study of Addiction.
Interaction effects on galaxy pairs with Gemini/GMOS- III: stellar population synthesis
NASA Astrophysics Data System (ADS)
Krabbe, A. C.; Rosa, D. A.; Pastoriza, M. G.; Hägele, G. F.; Cardaci, M. V.; Dors, O. L., Jr.; Winge, C.
2017-05-01
We present an observational study of the impacts of interactions on the stellar population in a sample of galaxy pairs. Long-slit spectra in the wavelength range 3440-7300 Å obtained with the Gemini Multi-Object Spectrograph (GMOS) at Gemini South for 15 galaxies in nine close pairs were used. The spatial distributions of the stellar population contributions were obtained using the stellar population synthesis code starlight. Taking into account the different contributions to the emitted light, we found that most of the galaxies in our sample are dominated by young/intermediate stellar populations. This result differs from the one derived for isolated galaxies, where the old stellar population dominates the disc surface brightness. We interpreted such different behaviour as being due to the effect of gas inflows along the discs of interacting galaxies on the star formation over a time-scale of the order of about 2 Gyr. We also found that, in general, the secondary galaxy of a pair has a higher contribution from the young stellar population than the primary one. We compared the estimated values of stellar and nebular extinction derived from the synthesis method and the Hα/Hβ emission-line ratio, finding that nebular extinctions are systematically higher than stellar ones by about a factor of 2. We did not find any correlation between nebular and stellar metallicities. Neither did we find a correlation between stellar metallicities and ages, while a positive correlation between nebular metallicities and stellar ages was obtained, with older regions being the most metal-rich.
Zhang, Boyu; Jia, Yanbin; Yuan, Yanbo; Yu, Xin; Xu, Qi; Shen, Yucun; Shen, Yan
2004-09-01
Several lines of evidence suggest that dysfunctions of neurotransmitters are associated with schizophrenia. DOPA decarboxylase (DDC) is an enzyme involved directly in the synthesis of dopamine and serotonin, and indirectly in the synthesis of noradrenaline. Therefore, the DDC gene can be considered a candidate gene for schizophrenia. We performed an association study between three single nucleotide polymorphisms in the DDC gene and paranoid schizophrenia. However, in our study no significant differences were found in the genotype distributions and allele frequencies between 80 paranoid schizophrenics and 108 controls for any of the polymorphisms. Neither did the haplotypes of the single nucleotide polymorphisms show any association with paranoid schizophrenia. Therefore, we conclude that the polymorphisms studied do not play a major role in paranoid schizophrenia pathogenesis in the population investigated.
ERIC Educational Resources Information Center
Deaton, Brady J.; McNamara, Kevin T.
A synthesis of research findings addressing effects of population and economic changes on education supply and demand in rural communities also presents policy implications, to help with local decision making. Principal research findings listed include: lack of a statistical relationship between per pupil expenditures and achievement on…
Ecological adaptations in Douglas-fir (Psuedotsuga menziesii var. glauca): a synthesis
Gerald Rehfeldt
1989-01-01
Measurements of 3rd-year height of 228 seedling populations, grown in four separate studies in two of the same common gardens, were used to summarize patterns of genetic variation for Douglas-fir across 250 000 km 2 of forested lands in Idaho and Montana, U.S.A. Because each study was conducted in different years with a different set of populations, measurements were...
The Question of Elitism: Some Movement to the Left?
ERIC Educational Resources Information Center
Haack, Paul
1987-01-01
Calls for a synthesis of beneficial elitism and beneficial populism to ensure excellence for all. Suggests that Robert Penn Warren's views on how to collapse dualisms between these two philosophies provides the key to their synthesis. Concludes by comparing differences between elitism and populism and examining questions raised by Ralph Smith's…
The epidemiology of HIV infection in Morocco: systematic review and data synthesis
Kouyoumjian, S P; Mumtaz, G R; Hilmi, N; Zidouh, A; El Rhilani, H; Alami, K; Bennani, A; Gouws, E; Ghys, P D; Abu-Raddad, L J
2013-01-01
Summary Morocco has made significant strides in building its HIV research capacity. Based on a wealth of empirical data, the objective of this study was to conduct a comprehensive and systematic literature review and analytical synthesis of HIV epidemiological evidence in this country. Data were retrieved using three major sources of literature and data. HIV transmission dynamics were found to be focused in high-risk populations, with female sex workers (FSWs) and clients contributing the largest share of new HIV infections. There is a pattern of emerging epidemics among some high-risk populations, and some epidemics, particularly among FSWs, appear to be established and stable. The scale of the local HIV epidemics and populations affected show highly heterogeneous geographical distribution. To optimize the national HIV response, surveillance and prevention efforts need to be expanded among high-risk populations and in geographic settings where low intensity and possibly concentrated HIV epidemics are emerging or are already endemic. PMID:23970764
Wolf-Rayet stars, black holes and the first detected gravitational wave source
NASA Astrophysics Data System (ADS)
Bogomazov, A. I.; Cherepashchuk, A. M.; Lipunov, V. M.; Tutukov, A. V.
2018-01-01
The recently discovered burst of gravitational waves GW150914 provides a good new chance to verify the current view on the evolution of close binary stars. Modern population synthesis codes help to study this evolution from two main sequence stars up to the formation of two final remnant degenerate dwarfs, neutron stars or black holes (Masevich and Tutukov, 1988). To study the evolution of the GW150914 predecessor we use the ;Scenario Machine; code presented by Lipunov et al. (1996). The scenario modeling conducted in this study allowed to describe the evolution of systems for which the final stage is a massive BH+BH merger. We find that the initial mass of the primary component can be 100÷140M⊙ and the initial separation of the components can be 50÷350R⊙. Our calculations show the plausibility of modern evolutionary scenarios for binary stars and the population synthesis modeling based on it.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Côté, Benoit; Belczynski, Krzysztof; Fryer, Chris L.
The role of compact binary mergers as the main production site of r-process elements is investigated by combining stellar abundances of Eu observed in the Milky Way, galactic chemical evolution (GCE) simulations, and binary population synthesis models, and gravitational wave measurements from Advanced LIGO. We compiled and reviewed seven recent GCE studies to extract the frequency of neutron star–neutron star (NS–NS) mergers that is needed in order to reproduce the observed [Eu/Fe] versus [Fe/H] relationship. We used our simple chemical evolution code to explore the impact of different analytical delay-time distribution functions for NS–NS mergers. We then combined our metallicity-dependent population synthesis models with our chemical evolution code to bring their predictions, for both NS–NS mergers and black hole–neutron star mergers, into a GCE context. Finally, we convolved our results with the cosmic star formation history to provide a direct comparison with current and upcoming Advanced LIGO measurements. When assuming that NS–NS mergers are the exclusive r-process sites, and that the ejected r-process mass per merger event is 0.01 Mmore » $${}_{\\odot }$$, the number of NS–NS mergers needed in GCE studies is about 10 times larger than what is predicted by standard population synthesis models. Here, these two distinct fields can only be consistent with each other when assuming optimistic rates, massive NS–NS merger ejecta, and low Fe yields for massive stars. For now, population synthesis models and GCE simulations are in agreement with the current upper limit (O1) established by Advanced LIGO during their first run of observations. Upcoming measurements will provide an important constraint on the actual local NS–NS merger rate, will provide valuable insights on the plausibility of the GCE requirement, and will help to define whether or not compact binary mergers can be the dominant source of r-process elements in the universe.« less
Advanced LIGO constraints on neutron star mergers and r-process sites
Côté, Benoit; Belczynski, Krzysztof; Fryer, Chris L.; ...
2017-02-20
The role of compact binary mergers as the main production site of r-process elements is investigated by combining stellar abundances of Eu observed in the Milky Way, galactic chemical evolution (GCE) simulations, and binary population synthesis models, and gravitational wave measurements from Advanced LIGO. We compiled and reviewed seven recent GCE studies to extract the frequency of neutron star–neutron star (NS–NS) mergers that is needed in order to reproduce the observed [Eu/Fe] versus [Fe/H] relationship. We used our simple chemical evolution code to explore the impact of different analytical delay-time distribution functions for NS–NS mergers. We then combined our metallicity-dependent population synthesis models with our chemical evolution code to bring their predictions, for both NS–NS mergers and black hole–neutron star mergers, into a GCE context. Finally, we convolved our results with the cosmic star formation history to provide a direct comparison with current and upcoming Advanced LIGO measurements. When assuming that NS–NS mergers are the exclusive r-process sites, and that the ejected r-process mass per merger event is 0.01 Mmore » $${}_{\\odot }$$, the number of NS–NS mergers needed in GCE studies is about 10 times larger than what is predicted by standard population synthesis models. Here, these two distinct fields can only be consistent with each other when assuming optimistic rates, massive NS–NS merger ejecta, and low Fe yields for massive stars. For now, population synthesis models and GCE simulations are in agreement with the current upper limit (O1) established by Advanced LIGO during their first run of observations. Upcoming measurements will provide an important constraint on the actual local NS–NS merger rate, will provide valuable insights on the plausibility of the GCE requirement, and will help to define whether or not compact binary mergers can be the dominant source of r-process elements in the universe.« less
Radiosensitivity of Mammalian Cells
Walters, R. A.; Petersen, D. F.
1968-01-01
Radiation effects on macromolecular synthesis essential for the Chinese hamster cell to traverse the life cycle and to divide have been investigated. Life-cycle analysis techniques employing inhibitors of macromolecular synthesis were used in determining the kinetics of cell growth for specific segments of the population following spontaneous recovery from radiation-induced division delay. The results indicated that recovery does not occur in the absence of functional protein synthesis. Under conditions which inhibit normal RNA and DNA synthesis, irradiated cells can recover the capacity to traverse the life cycle and to divide. The stability of mRNA species coding for proteins essential for division in irradiated cells was also measured. The mean functional lifetime of these mRNA species was 1 hr. The data demonstrate the existence of a specific segment of the population consisting of cells which have completed transcription related to division but not concomitant translation and which can recover from the radiation injury without synthesis of additional RNA. Thus, initial recovery of the ability to divide has an obligate requirement for protein synthesis but no corresponding requirement for nucleic acid synthesis during the period when original messenger remains intact. PMID:5753224
Studies of threespine stickleback developmental evolution: progress and promise.
Cresko, William A; McGuigan, Katrina L; Phillips, Patrick C; Postlethwait, John H
2007-01-01
A promising route for understanding the origin and diversification of organismal form is through studies at the intersection of evolution and development (evo-devo). While much has been learned over the last two decades concerning macroevolutionary patterns of developmental change, a fundamental gap in the evo-devo synthesis is the integration of mathematical population and quantitative genetics with studies of how genetic variation in natural populations affects developmental processes. This micro-evo-devo synthesis requires model organisms with which to ask empirical questions. Threespine stickleback fish (Gasterosteus aculeatus), long a model for studying behavior, ecology and evolution, is emerging as a prominent model micro-evo-devo system. Research on stickleback over the last decade has begun to address the genetic basis of morphological variation and sex determination, and much of this work has important implications for understanding the genetics of speciation. In this paper we review recent threespine stickleback micro-evo-devo results, and outline the resources that have been developed to make this synthesis possible. The prospects for stickleback research to speed the micro-(and macro-) evo-devo syntheses are great, and this workhorse model system is well situated to continue contributing to our understanding of the generation of diversity in organismal form for many more decades.
Biofield Therapies: Helpful or Full of Hype? A Best Evidence Synthesis
Mills, Paul J.
2009-01-01
Background Biofield therapies (such as Reiki, therapeutic touch, and healing touch) are complementary medicine modalities that remain controversial and are utilized by a significant number of patients, with little information regarding their efficacy. Purpose This systematic review examines 66 clinical studies with a variety of biofield therapies in different patient populations. Method We conducted a quality assessment as well as a best evidence synthesis approach to examine evidence for biofield therapies in relevant outcomes for different clinical populations. Results Studies overall are of medium quality, and generally meet minimum standards for validity of inferences. Biofield therapies show strong evidence for reducing pain intensity in pain populations, and moderate evidence for reducing pain intensity hospitalized and cancer populations. There is moderate evidence for decreasing negative behavioral symptoms in dementia and moderate evidence for decreasing anxiety for hospitalized populations. There is equivocal evidence for biofield therapies' effects on fatigue and quality of life for cancer patients, as well as for comprehensive pain outcomes and affect in pain patients, and for decreasing anxiety in cardiovascular patients. Conclusion There is a need for further high-quality studies in this area. Implications and future research directions are discussed. Electronic supplementary material The online version of this article (doi:10.1007/s12529-009-9062-4) contains supplementary material, which is available to authorized users. PMID:19856109
Formation and Evolution of X-ray Binaries
NASA Astrophysics Data System (ADS)
Fragkos, Anastasios
X-ray binaries - mass-transferring binary stellar systems with compact object accretors - are unique astrophysical laboratories. They carry information about many complex physical processes such as star formation, compact object formation, and evolution of interacting binaries. My thesis work involves the study of the formation and evolution of Galactic and extra-galacticX-ray binaries using both detailed and realistic simulation tools, and population synthesis techniques. I applied an innovative analysis method that allows the reconstruction of the full evolutionary history of known black hole X-ray binaries back to the time of compact object formation. This analysis takes into account all the available observationally determined properties of a system, and models in detail four of its evolutionary evolutionary phases: mass transfer through the ongoing X-ray phase, tidal evolution before the onset of Roche-lobe overflow, motion through the Galactic potential after the formation of the black hole, and binary orbital dynamics at the time of core collapse. Motivated by deep extra-galactic Chandra survey observations, I worked on population synthesis models of low-mass X-ray binaries in the two elliptical galaxies NGC3379 and NGC4278. These simulations were targeted at understanding the origin of the shape and normalization of the observed X-ray luminosity functions. In a follow up study, I proposed a physically motivated prescription for the modeling of transient neutron star low-mass X-ray binary properties, such as duty cycle, outburst duration and recurrence time. This prescription enabled the direct comparison of transient low-mass X-ray binary population synthesis models to the Chandra X-ray survey of the two ellipticals NGC3379 and NGC4278. Finally, I worked on population synthesismodels of black holeX-ray binaries in the MilkyWay. This work was motivated by recent developments in observational techniques for the measurement of black hole spin magnitudes in black hole X-ray binaries. The accuracy of these techniques depend on misalignment of the black hole spin with respect to the orbital angular momentum. In black hole X-ray binaries, this misalignment can occur during the supernova explosion that forms the compact object. In this study, I presented population synthesis models of Galactic black hole X-ray binaries, and examined the distribution of misalignment angles, and its dependence on the model parameters.
Reevaluating Old Stellar Populations
NASA Astrophysics Data System (ADS)
Stanway, E. R.; Eldridge, J. J.
2018-05-01
Determining the properties of old stellar populations (those with age >1 Gyr) has long involved the comparison of their integrated light, either in the form of photometry or spectroscopic indexes, with empirical or synthetic templates. Here we reevaluate the properties of old stellar populations using a new set of stellar population synthesis models, designed to incorporate the effects of binary stellar evolution pathways as a function of stellar mass and age. We find that single-aged stellar population models incorporating binary stars, as well as new stellar evolution and atmosphere models, can reproduce the colours and spectral indices observed in both globular clusters and quiescent galaxies. The best fitting model populations are often younger than those derived from older spectral synthesis models, and may also lie at slightly higher metallicities.
Optimizing the measurement of mitochondrial protein synthesis in human skeletal muscle.
Burd, Nicholas A; Tardif, Nicolas; Rooyackers, Olav; van Loon, Luc J C
2015-01-01
The measurement of mitochondrial protein synthesis after food ingestion, contractile activity, and/or disease is often used to provide insight into skeletal muscle adaptations that occur in the longer term. Studies have shown that protein ingestion stimulates mitochondrial protein synthesis in human skeletal muscle. Minor differences in the stimulation of mitochondrial protein synthesis occur after a single bout of resistance or endurance exercise. There appear to be no measurable differences in mitochondrial protein synthesis between critically ill patients and aged-matched controls. However, the mitochondrial protein synthetic response is reduced at a more advanced age. In this paper, we discuss the challenges involved in the measurement of human skeletal muscle mitochondrial protein synthesis rates based on stable isotope amino acid tracer methods. Practical guidelines are discussed to improve the reliability of the measurement of mitochondrial protein synthesis rates. The value of the measurement of mitochondrial protein synthesis after a single meal or exercise bout on the prediction of the longer term skeletal muscle mass and performance outcomes in both the healthy and disease populations requires more work, but we emphasize that the measurements need to be reliable to be of any value to the field.
Higgins, M. L.; Daneo-Moore, L.; Boothby, D.; Shockman, G. D.
1974-01-01
Selective inhibition of protein synthesis in Streptococcus faecalis (ATCC 9790) was accompanied by a rapid and severe inhibition of cell division and a reduction of enlargement of cellular surface area. Continued synthesis of cell wall polymers resulted in rapid thickening of the wall to an extent not seen in exponential-phase populations. Thus, the normal direction of wall growth was changed from a preferential feeding out of new wall surface to that of thickening existing cell surfaces. However, the overall manner in which the wall thickened, from nascent septa toward polar regions, was the same in both exponential-phase and inhibited populations. In contrast, selective inhibition of deoxyribonucleic acid (DNA) synthesis using mitomycin C was accompanied by an increase in cellular surface area and by division of about 80% of the cells in random populations. Little or no wall thickening was observed until the synthesis of macromolecules other than DNA was impaired and further cell division ceased. Concomitant inhibition of both DNA and protein synthesis inhibited cell division but permitted an increase in average cell volume. In such doubly inhibited cells, walls thickened less than in cells inhibited for protein synthesis only. On the basis of the results obtained, a model for cell surface enlargement and cell division is presented. The model proposes that: (i) each wall enlargement site is influenced by an individual chromosome replication cycle; (ii) during chromosome replication peripheral surface enlargement would be favored over thickening (or septation); (iii) a signal associated with chromosome termination would favor thickening (and septation) at the expense of surface enlargement; and (iv) a factor or signal related to protein synthesis would be required for one or more of the near terminal stages of cell division or cell separation, or both. Images PMID:4133352
NOAA Fisheries Toolbox - Welcome
Fitting Model » Stock Synthesis Version 3 » Survival Estimation in Non-Equilibrium situations » Virtual -Sissenwine Analysis (CSA) 4.3 01/13/2014 Dual Zone Virtual Population Analysis (VPA-2BOX) 3.05 8/4/2004 /2013 Stock Synthesis Version 3 (SS3) 3.45f 10/18/2012 Virtual Population Analysis (VPA) 3.4.4 3/3/2014
Hutchinson, Rebecca Newlin; Shin, Sonya
2014-01-01
Background American Indians and Alaska Native (AI/AN) populations experience significant health disparities compared to non-Hispanic white populations. Cardiovascular disease and related risk factors are increasingly recognized as growing indicators of global health disparities. However, comparative reports on disparities among this constellation of diseases for AI/AN populations have not been systematically reviewed. Objectives We performed a literature review on the prevalence of diabetes, metabolic syndrome, dyslipidemia, obesity, hypertension, and cardiovascular disease; and associated morbidity and mortality among AI/AN. Data sources A total of 203 articles were reviewed, of which 31 met study criteria for inclusion. Searches were performed on PUBMED, MEDLINE, the CDC MMWR, and the Indian Health Services. Study eligibility criteria Published literature that were published within the last fifteen years and provided direct comparisons between AI/AN to non-AI/AN populations were included. Study appraisal and synthesis methods We abstracted data on study design, data source, AI/AN population, comparison group, and. outcome measures. A descriptive synthesis of primary findings is included. Results Rates of obesity, diabetes, cardiovascular disease, and metabolic syndrome are clearly higher for AI/AN populations. Hypertension and hyperlipidemia differences are more equivocal. Our analysis also revealed that there are likely regional and gender differences in the degree of disparities observed. Limitations Studies using BRFSS telephone surveys administered in English may underestimate disparities. Many AI/AN do not have telephones and/or speak English. Regional variability makes national surveys difficult to interpret. Finally, studies using self-reported data may not be accurate. Conclusions and implications of key findings Profound health disparities in cardiovascular diseases and associated risk factors for AI/AN populations persist, perhaps due to low socioeconomic status and access to quality healthcare. Successful programs will address social determinants and increase healthcare access. Community-based outreach to bring health services to the most vulnerable may also be very helpful in this effort. Systematic review registration number N/A PMID:24454685
NASA Technical Reports Server (NTRS)
Lehmer, B. D.; Berkeley, M.; Zezas, A.; Alexander, D. M.; Basu-Zych, A.; Bauer, F. E.; Brandt, W. N.; Fragos, T.; Hornschemeier, A. E.; Kalogera, V.;
2014-01-01
We present direct constraints on how the formation of low-mass X-ray binary (LMXB) populations in galactic fields depends on stellar age. In this pilot study, we utilize Chandra and Hubble Space Telescope (HST) data to detect and characterize the X-ray point source populations of three nearby early-type galaxies: NGC 3115, 3379, and 3384. The luminosity-weighted stellar ages of our sample span approximately equal to 3-10 Gyr. X-ray binary population synthesis models predict that the field LMXBs associated with younger stellar populations should be more numerous and luminous per unit stellar mass than older populations due to the evolution of LMXB donor star masses. Crucially, the combination of deep Chandra and HST observations allows us to test directly this prediction by identifying and removing counterparts to X-ray point sources that are unrelated to the field LMXB populations, including LMXBs that are formed dynamically in globular clusters, Galactic stars, and background AGN/galaxies. We find that the "young" early-type galaxy NGC 3384 (approximately equals 2-5 Gyr) has an excess of luminous field LMXBs (L(sub x) approximately greater than (5-10) × 10(exp 37) erg s(exp -1)) per unit K-band luminosity (L(sub K); a proxy for stellar mass) than the "old" early-type galaxies NGC 3115 and 3379 (approximately equals 8-10 Gyr), which results in a factor of 2-3 excess of L(sub X)/L(sub K) for NGC 3384. This result is consistent with the X-ray binary population synthesis model predictions; however, our small galaxy sample size does not allow us to draw definitive conclusions on the evolution field LMXBs in general. We discuss how future surveys of larger galaxy samples that combine deep Chandra and HST data could provide a powerful new benchmark for calibrating X-ray binary population synthesis models.
Absorption line indices in the UV. I. Empirical and theoretical stellar population models
NASA Astrophysics Data System (ADS)
Maraston, C.; Nieves Colmenárez, L.; Bender, R.; Thomas, D.
2009-01-01
Aims: Stellar absorption lines in the optical (e.g. the Lick system) have been extensively studied and constitute an important stellar population diagnostic for galaxies in the local universe and up to moderate redshifts. Proceeding towards higher look-back times, galaxies are younger and the ultraviolet becomes the relevant spectral region where the dominant stellar populations shine. A comprehensive study of ultraviolet absorption lines of stellar population models is however still lacking. With this in mind, we study absorption line indices in the far and mid-ultraviolet in order to determine age and metallicity indicators for UV-bright stellar populations in the local universe as well as at high redshift. Methods: We explore empirical and theoretical spectral libraries and use evolutionary population synthesis to compute synthetic line indices of stellar population models. From the empirical side, we exploit the IUE-low resolution library of stellar spectra and system of absorption lines, from which we derive analytical functions (fitting functions) describing the strength of stellar line indices as a function of gravity, temperature and metallicity. The fitting functions are entered into an evolutionary population synthesis code in order to compute the integrated line indices of stellar populations models. The same line indices are also directly evaluated on theoretical spectral energy distributions of stellar population models based on Kurucz high-resolution synthetic spectra, In order to select indices that can be used as age and/or metallicity indicators for distant galaxies and globular clusters, we compare the models to data of template globular clusters from the Magellanic Clouds with independently known ages and metallicities. Results: We provide synthetic line indices in the wavelength range ~1200 Å to ~3000 Å for stellar populations of various ages and metallicities.This adds several new indices to the already well-studied CIV and SiIV absorptions. Based on the comparison with globular cluster data, we select a set of 11 indices blueward of the 2000 Å rest-frame that allows us to recover well the ages and the metallicities of the clusters. These indices are ideal to study ages and metallicities of young galaxies at high redshift. We also provide the synthetic high-resolution stellar population SEDs.
Royle, J. Andrew; Chandler, Richard B.; Sollmann, Rahel; Gardner, Beth
2013-01-01
Spatial Capture-Recapture provides a revolutionary extension of traditional capture-recapture methods for studying animal populations using data from live trapping, camera trapping, DNA sampling, acoustic sampling, and related field methods. This book is a conceptual and methodological synthesis of spatial capture-recapture modeling. As a comprehensive how-to manual, this reference contains detailed examples of a wide range of relevant spatial capture-recapture models for inference about population size and spatial and temporal variation in demographic parameters. Practicing field biologists studying animal populations will find this book to be a useful resource, as will graduate students and professionals in ecology, conservation biology, and fisheries and wildlife management.
NASA Technical Reports Server (NTRS)
Walker, T. P.; Steigman, G.; Schramm, D. N.; Olive, K. A.; Fields, B.
1993-01-01
We discuss Galactic cosmic-ray (GCR) spallation production of Li, Be, and B in the early Galaxy with particular attention to the uncertainties in the predictions of this model. The observed correlation between the Be abundance and the metallicity in metal-poor Population II stars requires that Be was synthesized in the early Galaxy. We show that the observations and such Population II GCR synthesis of Be are quantitatively consistent with the big bang nucleosynthesis production of Li-7. We find that there is a nearly model independent lower bound to B/Be of about 7 for GCR synthesis. Recent measurements of B/Be about 10 in HD 140283 are in excellent agreement with the predictions of Population II GCR nucleosynthesis. Measurements of the boron abundance in additional metal-poor halo stars is a key diagnostic of the GCR spallation mechanism. We also show that Population II GCR synthesis can produce amounts of Li-6 which may be observed in the hottest halo stars.
Wang, Xiaoguang; Miller, Daniel S.; de Pablo, Juan J.; ...
2014-08-15
The spontaneous positioning of colloids on the surfaces of micrometer-sized liquid crystal (LC) droplets and their subsequent polymerization offers the basis of a general and facile method for the synthesis of patchy microparticles. The existence of multiple local energetic minima, however, can generate kinetic traps for colloids on the surfaces of the LC droplets and result in heterogeneous populations of patchy microparticles. To address this issue, in this paper it is demonstrated that adsorbate-driven switching of the internal configurations of LC droplets can be used to sweep colloids to a single location on the LC droplet surfaces, thus resulting inmore » the synthesis of homogeneous populations of patchy microparticles. The surface-driven switching of the LC can be triggered by addition of surfactant or salts, and permits the synthesis of dipolar microparticles as well as “Janus-like” microparticles. Finally, by using magnetic colloids, the utility of the approach is illustrated by synthesizing magnetically responsive patchy microdroplets of LC with either dipolar or quadrupolar symmetry that exhibit distinct optical responses upon application of an external magnetic field.« less
Duval, Sarah; Carretier, Julien; Boyle, Helen; Philip, Thierry; Berger, Claire; Marec-Bérard, Perrine; Fervers, Béatrice
2015-01-01
Survival of children, adolescents and young adults treated for cancer increased with improved treatments. But there is still an increased risk of second primary cancer (SPC) in the long term compared to the population of the same age, especially related to treatments. A reflection on the follow-up of this population and the prevention of SPC is an important issue. To perform a synthesis of the available literature on SCP risk factors, related risk behaviors, occupational exposures and prevention strategies. Literature search on PubMed from the following equation: "cancer [Tiab] AND young adult [Tiab] or teen [Tiab] or childhood [Tiab] AND prevention [Tiab] AND survivors [Mesh term]". Twenty-seven articles were included in this synthesis. Children, adolescents and young adults have similar risk behaviors than those of their peers regarding tobacco, diet and sun exposure; however, they have lower physical activity. There are few studies on prevention strategies focused on this population. Results of available studies remain inconclusive. No publication was found in relation to occupational exposure and risk of second cancer. Children, adolescents and young adults treated for cancer are a population at risk and require long-term follow-up and the implementation of effective prevention strategies tailored to this population. Copyright © 2015 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.
Prospective study of serum B vitamins levels and oesophageal and gastric cancers in China
USDA-ARS?s Scientific Manuscript database
B vitamins play an essential role in DNA synthesis and methylation, and may protect against oesophageal and gastric cancers. In this case-cohort study, subjects were enrolled from the General Population Nutrition Intervention Trial in Linxian, China. Subjects included 498 oesophageal squamous cell c...
Soler, Juan; Soler, Manuel
2000-11-01
Brood parasitism is one of the systems where coevolutionary processes have received the most research. Here, we review experiments that suggest a coevolutionary process between the great spotted cuckoo (Clamator glandarius) and its magpie (Pica pica) host. We focus on different stages of establishment of the relationship, from cuckoos selecting individual hosts and hosts defending their nests from adult cuckoos, to the ability of magpies to detect cuckoo eggs in their nests. Novel coevolutionary insights emerge from our synthesis of the literature, including how the evolution of "Mafia" behaviour in cuckoos does not necessarily inhibit the evolution of host recognition and rejection of cuckoo offspring, and how different populations of black-billed magpies in Europe have evolved specific host traits (e.g. nest and clutch size) as a result of interactions with the great spotted cuckoo. Finally, the results of the synthesis reveal the importance of using a meta-population approach when studying coevolution. This is especially relevant in those cases where gene flow among populations with different degrees of brood parasitism explains patterns of coexistence between defensive and non-defensive host phenotypes. We propose the use of a meta-population approach to distinguish between the "evolutionary equilibrium" hypothesis and the "evolutionary lag" hypothesis.
Synthesis and assessment of date palm genetic diversity studies
USDA-ARS?s Scientific Manuscript database
A thorough assessment of genetic diversity and population differentiation of Phoenix dactylifera are critical for its dynamic conservation and sustainable utilization of its genetic diversity. Estimates of genetic diversity based on phenotypic, biochemical and molecular markers; and fruit quality tr...
Treatment, Time, and Achievement: Do Searching Modes of Study Facilitate Learning?
ERIC Educational Resources Information Center
Rice, Marion J.
This report is a synthesis of five research studies comparing the facilitative effects on learning of searching and reception modes of study. The following five studies are discussed: (1) J.R. Dale, the effects on achievement of using the forced inferential response mode in an intermediate grade population-geography unit; (2) D.D. Dumbleton, the…
NASA Technical Reports Server (NTRS)
Fanelli, Michael N.; O'Connell, Robert W.; Thuan, Trinh X.
1988-01-01
An initial attempt to apply optimizing spectral synthesis techniques to the far-UV spectra of blue compact galaxies (BCGs) is presented. The far-UV absorption-line spectra of the galaxies are clearly composite, with the signatures of the main-sequence types between O3 and mid-A. Most of the low-ionization absorption lines have a stellar origin. The Si IV and C IV features in several objects have P Cygni profiles. In Haro I the strength of Si IV indicates a significant blue supergiant population. The metal-poor blue compact dwarf Mrk 209 displays weak absorption lines, evidence that the stellar component has the same low metallicity as observed in the ionized gas. Good fits to the data are obtained the technique of optimizing population synthesis. The solutions yield stellar luminosity functions which display large discontinuities, indicative of discrete star formation episodes or bursts. The amount of UV extinction is low.
ERIC Educational Resources Information Center
Kingston, Neal M.
2009-01-01
There have been many studies of the comparability of computer-administered and paper-administered tests. Not surprisingly (given the variety of measurement and statistical sampling issues that can affect any one study) the results of such studies have not always been consistent. Moreover, the quality of computer-based test administration systems…
Climate change effects on North American inland fish populations and assemblages
Lynch, Abigail J.; Myers, Bonnie; Chu, Cindy; Eby, Lisa A.; Falke, Jeffrey A.; Kovach, Ryan P.; Krabbenhoft, Trevor J.; Kwak, Thomas J.; Lyons, John; Paukert, Craig P.; Whitney, James E.
2016-01-01
Climate is a critical driver of many fish populations, assemblages, and aquatic communities. However, direct observational studies of climate change impacts on North American inland fishes are rare. In this synthesis, we (1) summarize climate trends that may influence North American inland fish populations and assemblages, (2) compile 31 peer-reviewed studies of documented climate change effects on North American inland fish populations and assemblages, and (3) highlight four case studies representing a variety of observed responses ranging from warmwater systems in the southwestern and southeastern United States to coldwater systems along the Pacific Coast and Canadian Shield. We conclude by identifying key data gaps and research needs to inform adaptive, ecosystem-based approaches to managing North American inland fishes and fisheries in a changing climate.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stevenson, Simon; Ohme, Frank; Fairhurst, Stephen, E-mail: simon.stevenson@ligo.org
2015-09-01
The coalescence of compact binaries containing neutron stars or black holes is one of the most promising signals for advanced ground-based laser interferometer gravitational-wave (GW) detectors, with the first direct detections expected over the next few years. The rate of binary coalescences and the distribution of component masses is highly uncertain, and population synthesis models predict a wide range of plausible values. Poorly constrained parameters in population synthesis models correspond to poorly understood astrophysics at various stages in the evolution of massive binary stars, the progenitors of binary neutron star and binary black hole systems. These include effects such asmore » supernova kick velocities, parameters governing the energetics of common envelope evolution and the strength of stellar winds. Observing multiple binary black hole systems through GWs will allow us to infer details of the astrophysical mechanisms that lead to their formation. Here we simulate GW observations from a series of population synthesis models including the effects of known selection biases, measurement errors and cosmology. We compare the predictions arising from different models and show that we will be able to distinguish between them with observations (or the lack of them) from the early runs of the advanced LIGO and Virgo detectors. This will allow us to narrow down the large parameter space for binary evolution models.« less
Thermal Timescale Mass Transfer In Binary Population Synthesis
NASA Astrophysics Data System (ADS)
Justham, S.; Kolb, U.
2004-07-01
Studies of binary evolution have, until recently, neglected thermal timescale mass transfer (TTMT). Recent work has suggested that this previously poorly studied area is crucial in the understanding of systems across the compact binary spectrum. We use the state-of-the-art binary population synthesis code BiSEPS (Willems and Kolb, 2002, MNRAS 337 1004-1016). However, the present treatment of TTMT is incomplete due to the nonlinear behaviour of stars in their departure from gravothermal `equilibrium'. Here we show work that should update the ultrafast stellar evolution algorithms within BiSEPS to make it the first pseudo-analytic code that can follow TTMT properly. We have generated fits to a set of over 300 Case B TTMT sequences with a range of intermediate-mass donors. These fits produce very good first approximations to both HR diagrams and mass-transfer rates (see figures 1 and 2), which we later hope to improve and extend. They are already a significant improvement over the previous fits.
Evidence-Based Psychosocial Treatments for Eating Problems and Eating Disorders
ERIC Educational Resources Information Center
Keel, Pamela K.; Haedt, Alissa
2008-01-01
Eating disorders represent a significant source of psychological impairment among adolescents. However, most controlled treatment studies have focused on adult populations. This review provides a synthesis of existing data concerning the efficacy of various psychosocial interventions for eating disorders in adolescent samples. Modes of therapy…
Honein-AbouHaidar, Gladys N; Kastner, Monika; Vuong, Vincent; Perrier, Laure; Daly, Corinne; Rabeneck, Linda; Straus, Sharon; Baxter, Nancy N
2016-06-01
Screening reduces the incidence, morbidity, and mortality of colorectal cancer, yet participation tends to be low. We undertook a systematic review and meta-study synthesis of qualitative studies to identify facilitators and barriers to colorectal cancer screening participation. We searched major bibliographic databases for records published in all languages from inception to February 2015. Included primary studies that elicited views and perceptions towards colorectal cancer screening were appraised for relevance and quality. We used a two-stage synthesis to create an interpretation of colorectal cancer screening decisions grounded in primary studies; a thematic analysis to group themes and systematically compare studies and a meta-synthesis to generate an expanded theory of colorectal cancer screening participation. Ninety-four studies were included. The decision to participate in colorectal cancer screening depended on an individual's awareness of colorectal cancer screening. Awareness affected views of cancer, attitudes towards colorectal cancer screening modalities, and motivation for screening. Factors mediating awareness included public education to address misconceptions, primary care physician efforts to recommend screening, and the influence of friends and family. Specific barriers to participation in populations with lower participation rates included language barriers, logistical challenges to attending screening tests, and cultural beliefs. This study identifies key barriers, facilitators, and mediators to colorectal cancer screening participation. Cancer Epidemiol Biomarkers Prev; 25(6); 907-17. ©2016 AACR. ©2016 American Association for Cancer Research.
LA SYNTHÈSE DE L'ADN MITOCHONDRIAL CHEZ TETRAHYMENA PYRIFORMIS
Charret, Renée; André, Jean
1968-01-01
Electron microscopic radioautography has been used to study the synthesis of mitochondrial DNA after incorporation of thymidine-3H by cultures in logarithmic phase of Tetrahymena pyriformis during periods ranging from 15 min to 12 hr. The great majority of silver grains are distributed over the macronuclei, the micronuclei, and the mitochondria. The intensity of the label over the entire mitochondrial population is a function of the length of the incubation period within the time interval considered. The intensity of the mitochondrial label was compared with that of the nuclear label. Mitochondria incorporate at the same rate whether the nuclei are synthesizing or not. This persistence of mitochondrial incorporation in the absence of nuclear incorporation excludes the hypothesis of a nuclear origin for mitochondrial DNA. We are not able to determine whether the apparent continuity of synthesis in the entire mitochondrial population of a cell actually represents a series of asynchronous discontinuities. PMID:5677970
A Perspective on Micro-Evo-Devo: Progress and Potential
Nunes, Maria D. S.; Arif, Saad; Schlötterer, Christian; McGregor, Alistair P.
2013-01-01
The term “micro-evo-devo” refers to the combined study of the genetic and developmental bases of natural variation in populations and the evolutionary forces that have shaped this variation. It thus represents a synthesis of the fields of evolutionary developmental biology and population genetics. As has been pointed out by several others, this synthesis can provide insights into the evolution of organismal form and function that have not been possible within these individual disciplines separately. Despite a number of important successes in micro-evo-devo, however, it appears that evo devo and population genetics remain largely separate spheres of research, limiting their ability to address evolutionary questions. This also risks pushing contemporary evo devo to the fringes of evolutionary biology because it does not describe the causative molecular changes underlying evolution or the evolutionary forces involved. Here we reemphasize the theoretical and practical importance of micro-evo-devo as a strategy for understanding phenotypic evolution, review the key recent insights that it has provided, and present a perspective on both the potential and the remaining challenges of this exciting interdisciplinary field. PMID:24190920
A perspective on micro-evo-devo: progress and potential.
Nunes, Maria D S; Arif, Saad; Schlötterer, Christian; McGregor, Alistair P
2013-11-01
The term "micro-evo-devo" refers to the combined study of the genetic and developmental bases of natural variation in populations and the evolutionary forces that have shaped this variation. It thus represents a synthesis of the fields of evolutionary developmental biology and population genetics. As has been pointed out by several others, this synthesis can provide insights into the evolution of organismal form and function that have not been possible within these individual disciplines separately. Despite a number of important successes in micro-evo-devo, however, it appears that evo devo and population genetics remain largely separate spheres of research, limiting their ability to address evolutionary questions. This also risks pushing contemporary evo devo to the fringes of evolutionary biology because it does not describe the causative molecular changes underlying evolution or the evolutionary forces involved. Here we reemphasize the theoretical and practical importance of micro-evo-devo as a strategy for understanding phenotypic evolution, review the key recent insights that it has provided, and present a perspective on both the potential and the remaining challenges of this exciting interdisciplinary field.
Maleku, Arati; Aguirre, Regina T P
2014-01-01
Immigrant groups comprise a large segment of ethnic minorities in the United States. Although the literature is rich with strategies to deliver culturally and linguistically appropriate services to eliminate health inequities, studies addressing cultural competence from the immigrant's perspective are limited. Further research is needed to build knowledge of the predictors and needs of this population, and to influence health care policy and practice. Using qualitative interpretive meta-synthesis, this study describes the lived experience of immigrants accessing health care to understand the essence of cultural competence in health care through their lens. Findings provide insight on expanding the definition of culturally competent health care beyond language, behaviors, attitudes, and policies.
Matrix population models from 20 studies of perennial plant populations
Ellis, Martha M.; Williams, Jennifer L.; Lesica, Peter; Bell, Timothy J.; Bierzychudek, Paulette; Bowles, Marlin; Crone, Elizabeth E.; Doak, Daniel F.; Ehrlen, Johan; Ellis-Adam, Albertine; McEachern, Kathryn; Ganesan, Rengaian; Latham, Penelope; Luijten, Sheila; Kaye, Thomas N.; Knight, Tiffany M.; Menges, Eric S.; Morris, William F.; den Nijs, Hans; Oostermeijer, Gerard; Quintana-Ascencio, Pedro F.; Shelly, J. Stephen; Stanley, Amanda; Thorpe, Andrea; Tamara, Ticktin; Valverde, Teresa; Weekley, Carl W.
2012-01-01
Demographic transition matrices are one of the most commonly applied population models for both basic and applied ecological research. The relatively simple framework of these models and simple, easily interpretable summary statistics they produce have prompted the wide use of these models across an exceptionally broad range of taxa. Here, we provide annual transition matrices and observed stage structures/population sizes for 20 perennial plant species which have been the focal species for long-term demographic monitoring. These data were assembled as part of the "Testing Matrix Models" working group through the National Center for Ecological Analysis and Synthesis (NCEAS). In sum, these data represent 82 populations with >460 total population-years of data. It is our hope that making these data available will help promote and improve our ability to monitor and understand plant population dynamics.
Matrix population models from 20 studies of perennial plant populations
Ellis, Martha M.; Williams, Jennifer L.; Lesica, Peter; Bell, Timothy J.; Bierzychudek, Paulette; Bowles, Marlin; Crone, Elizabeth E.; Doak, Daniel F.; Ehrlen, Johan; Ellis-Adam, Albertine; McEachern, Kathryn; Ganesan, Rengaian; Latham, Penelope; Luijten, Sheila; Kaye, Thomas N.; Knight, Tiffany M.; Menges, Eric S.; Morris, William F.; den Nijs, Hans; Oostermeijer, Gerard; Quintana-Ascencio, Pedro F.; Shelly, J. Stephen; Stanley, Amanda; Thorpe, Andrea; Tamara, Ticktin; Valverde, Teresa; Weekley, Carl W.
2012-01-01
Demographic transition matrices are one of the most commonly applied population models for both basic and applied ecological research. The relatively simple framework of these models and simple, easily interpretable summary statistics they produce have prompted the wide use of these models across an exceptionally broad range of taxa. Here, we provide annual transition matrices and observed stage structures/population sizes for 20 perennial plant species which have been the focal species for long-term demographic monitoring. These data were assembled as part of the 'Testing Matrix Models' working group through the National Center for Ecological Analysis and Synthesis (NCEAS). In sum, these data represent 82 populations with >460 total population-years of data. It is our hope that making these data available will help promote and improve our ability to monitor and understand plant population dynamics.
Adams, Noah; Hitomi, Maaya; Moody, Cherie
2017-01-01
Abstract Purpose: This article reports on the findings of a meta-synthesis undertaken on published gray transgender suicidality literature, to determine the average rate of suicidal ideation and attempts in this population. Methods: Studies included in this synthesis were restricted to the 42 that reported on 5 or more Canadian or U.S. adult participants, as published between 1997 and February 2016 in either gray or peer-reviewed health literature. Results: Across these 42 studies an average of 55% of respondents ideated about and 29% attempted suicide in their lifetimes. Within the past year, these averages were, respectively, 51% and 11%, or 14 and 22 times that of the general public. Overall, suicidal ideation was higher among individuals of a male-to-female (MTF) than female-to-male (FTM) alignment, and lowest among those who were gender non-conforming (GNC). Conversely, attempts occurred most often among FTM individuals, then decreased for MTF individuals, followed by GNC individuals. Conclusion: These findings may be useful in creating targeted interventions that take into account both the alarmingly high rate of suicidality in this population, and the relatively differential experience of FTM, MTF, and GNC individuals. Future research should examine minority stress theory and suicidality protection/resilience factors, particularly transition, on this population. PMID:28861548
ERIC Educational Resources Information Center
Sturges, Diana; Maurer, Trent W.; Cole, Oladipo
2009-01-01
This study investigated the effectiveness of role play in a large undergraduate science class. The targeted population consisted of 298 students enrolled in 2 sections of an undergraduate Human Anatomy and Physiology course taught by the same instructor. The section engaged in the role-play activity served as the study group, whereas the section…
COSMIC probes into compact binary formation and evolution
NASA Astrophysics Data System (ADS)
Breivik, Katelyn
2018-01-01
The population of compact binaries in the galaxy represents the final state of all binaries that have lived up to the present epoch. Compact binaries present a unique opportunity to probe binary evolution since many of the interactions binaries experience can be imprinted on the compact binary population. By combining binary evolution simulations with catalogs of observable compact binary systems, we can distill the dominant physical processes that govern binary star evolution, as well as predict the abundance and variety of their end products.The next decades herald a previously unseen opportunity to study compact binaries. Multi-messenger observations from telescopes across all wavelengths and gravitational-wave observatories spanning several decades of frequency will give an unprecedented view into the structure of these systems and the composition of their components. Observations will not always be coincident and in some cases may be separated by several years, providing an avenue for simulations to better constrain binary evolution models in preparation for future observations.I will present the results of three population synthesis studies of compact binary populations carried out with the Compact Object Synthesis and Monte Carlo Investigation Code (COSMIC). I will first show how binary-black-hole formation channels can be understood with LISA observations. I will then show how the population of double white dwarfs observed with LISA and Gaia could provide a detailed view of mass transfer and accretion. Finally, I will show that Gaia could discover thousands black holes in the Milky Way through astrometric observations, yielding view into black-hole astrophysics that is complementary to and independent from both X-ray and gravitational-wave astronomy.
Gould, Gillian Sandra; McEwen, Andy; Watters, Tracey; Clough, Alan R; van der Zwan, Rick
2013-07-01
To summarise published empirical research on culturally targeted anti-tobacco media messages for Indigenous or First Nations people and examine the evidence for the effectiveness of targeted and non-targeted campaigns. Studies were sought describing mass media and new media interventions for tobacco control or smoking cessation in Indigenous or First Nations populations. Studies of any design were included reporting outcomes of media-based interventions including: cognitions, awareness, recall, intention to quit and quit rates. Then, 2 reviewers independently applied inclusion criteria, which were met by 21 (5.8%) of the studies found. One author extracted data with crosschecking by a second. Both independently assessed papers using Scottish Intercollegiate Guidelines Network (SIGN; quantitative studies) and Daly et al (qualitative studies). A total of 21 studies were found (4 level 1 randomised controlled trials (RCTs), 11 level 2 studies and 6 qualitative studies) and combined with narrative synthesis. Eight evaluated anti-tobacco TV or radio campaigns; two assessed US websites; three New Zealand studies examined mobile phone interventions; five evaluated print media; three evaluated a CD-ROM, a video and an edutainment intervention. Although Indigenous people had good recall of generic anti-tobacco messages, culturally targeted messages were preferred. New Zealand Maori may be less responsive to holistic targeted campaigns, despite their additional benefits, compared to generic fear campaigns. Culturally targeted internet or mobile phone messages appear to be as effective in American Indians and Maori as generic messages in the general population. There is little research comparing the effect of culturally targeted versus generic messages with similar message content in Indigenous people.
Young, Gifted, and Female: A Look at Academic and Social Needs
ERIC Educational Resources Information Center
Meredith, Corine Cadle
2009-01-01
This article illuminates the current status of our understanding regarding the academic and social-emotional needs of gifted, early adolescent females in the United States. A synthesis of both theoretical and empirical studies addresses two foundational questions. First, how do we describe the unique population of gifted, female, adolescent…
USDA-ARS?s Scientific Manuscript database
Although the synthesis of oligosaccharides obtained by reactions catalyzed by dextransucrase using sucrose as donor and different carbohydrates as acceptors has been widely studied, the effect of many of these carbohydrates in the growth of intestinal flora has not yet been evaluated. Such is the c...
Conclusions, synthesis, and future directions: understanding sources of population change
Esler, Daniel N.; Flint, Paul L.; Derksen, Dirk V.; Savard, Jean-Pierre L.; Eadie, John M.
2015-01-01
The material in this volume reflects the burgeoning interest in sea ducks, both as study species with compelling and unique ecological attributes and as taxa of conservation concern. In this review, we provide perspective on the current state of sea duck knowledge by highlighting key findings in the preceding chapters that are of particular value for understanding or influencing population change. We also introduce a conceptual model that characterizes links among topics covered by individual chapters and places them in the context of demographic responses. Finally, we offer recommendations for areas of future research that we suggest will have importance for understanding and managing sea duck population dynamics.
Flow cytometric measurement of total DNA and incorporated halodeoxyuridine
Dolbeare, Frank A.; Gray, Joe W.
1986-01-01
A method for the simultaneous flow cytometric measurement of the total DNA content and the level of DNA synthesis in normal and malignant cells is disclosed. The sensitivity of the method allows a study of cell cycle traverse rates for large scale cell populations as well as single cell measurements. A DNA stain such as propidium iodide is used as the probe for the measurement of total DNA content and a monoclonal antibody reactive with a DNA precursor such as bromodeoxyuridine (BrdU) is used as a probe for the measurement of BrdU uptake by the cells as a measure of DNA synthesis.
Louis, Petra; Flint, Harry J
2009-05-01
Butyrate-producing bacteria play a key role in colonic health in humans. This review provides an overview of the current knowledge of the diversity, metabolism and microbial ecology of this functionally important group of bacteria. Human colonic butyrate producers are Gram-positive firmicutes, but are phylogenetically diverse, with the two most abundant groups related to Eubacterium rectale/Roseburia spp. and to Faecalibacterium prausnitzii. Five different arrangements have been identified for the genes of the central pathway involved in butyrate synthesis, while in most cases butyryl-CoA : acetate CoA-transferase, rather than butyrate kinase, appears to perform the final step in butyrate synthesis. Mechanisms have been proposed recently in non-gut Clostridium spp. whereby butyrate synthesis can result in energy generation via both substrate-level phosphorylation and proton gradients. Here we suggest that these mechanisms also apply to the majority of butyrate producers from the human colon. The roles of these bacteria in the gut community and their influence on health are now being uncovered, taking advantage of the availability of cultured isolates and molecular methodologies. Populations of F. prausnitzii are reported to be decreased in Crohn's disease, for example, while populations of Roseburia relatives appear to be particularly sensitive to the diet composition in human volunteer studies.
PopCORN: Hunting down the differences between binary population synthesis codes
NASA Astrophysics Data System (ADS)
Toonen, S.; Claeys, J. S. W.; Mennekens, N.; Ruiter, A. J.
2014-02-01
Context. Binary population synthesis (BPS) modelling is a very effective tool to study the evolution and properties of various types of close binary systems. The uncertainty in the parameters of the model and their effect on a population can be tested in a statistical way, which then leads to a deeper understanding of the underlying (sometimes poorly understood) physical processes involved. Several BPS codes exist that have been developed with different philosophies and aims. Although BPS has been very successful for studies of many populations of binary stars, in the particular case of the study of the progenitors of supernovae Type Ia, the predicted rates and ZAMS progenitors vary substantially between different BPS codes. Aims: To understand the predictive power of BPS codes, we study the similarities and differences in the predictions of four different BPS codes for low- and intermediate-mass binaries. We investigate the differences in the characteristics of the predicted populations, and whether they are caused by different assumptions made in the BPS codes or by numerical effects, e.g. a lack of accuracy in BPS codes. Methods: We compare a large number of evolutionary sequences for binary stars, starting with the same initial conditions following the evolution until the first (and when applicable, the second) white dwarf (WD) is formed. To simplify the complex problem of comparing BPS codes that are based on many (often different) assumptions, we equalise the assumptions as much as possible to examine the inherent differences of the four BPS codes. Results: We find that the simulated populations are similar between the codes. Regarding the population of binaries with one WD, there is very good agreement between the physical characteristics, the evolutionary channels that lead to the birth of these systems, and their birthrates. Regarding the double WD population, there is a good agreement on which evolutionary channels exist to create double WDs and a rough agreement on the characteristics of the double WD population. Regarding which progenitor systems lead to a single and double WD system and which systems do not, the four codes agree well. Most importantly, we find that for these two populations, the differences in the predictions from the four codes are not due to numerical differences, but because of different inherent assumptions. We identify critical assumptions for BPS studies that need to be studied in more detail. Appendices are available in electronic form at http://www.aanda.org
Geographical variation in species' population responses to changes in temperature and precipitation.
Pearce-Higgins, James W; Ockendon, Nancy; Baker, David J; Carr, Jamie; White, Elizabeth C; Almond, Rosamunde E A; Amano, Tatsuya; Bertram, Esther; Bradbury, Richard B; Bradley, Cassie; Butchart, Stuart H M; Doswald, Nathalie; Foden, Wendy; Gill, David J C; Green, Rhys E; Sutherland, William J; Tanner, Edmund V J
2015-11-07
Despite increasing concerns about the vulnerability of species' populations to climate change, there has been little overall synthesis of how individual population responses to variation in climate differ between taxa, with trophic level or geographically. To address this, we extracted data from 132 long-term (greater than or equal to 20 years) studies of population responses to temperature and precipitation covering 236 animal and plant species across terrestrial and freshwater habitats. Our results identify likely geographical differences in the effects of climate change on populations and communities in line with macroecological theory. Temperature tended to have a greater overall impact on populations than precipitation, although the effects of increased precipitation varied strongly with latitude, being most positive at low latitudes. Population responses to increased temperature were generally positive, but did not vary significantly with latitude. Studies reporting significant climatic trends through time tended to show more negative effects of temperature and more positive effects of precipitation upon populations than other studies, indicating climate change has already impacted many populations. Most studies of climate change impacts on biodiversity have focused on temperature and are from middle to high northern latitudes. Our results suggest their findings may be less applicable to low latitudes. © 2015 The Author(s).
Siaki, Leilani A; Loescher, Lois J; Trego, Lori L
2013-03-01
This article presents a discussion of development of a mid-range theory of risk perception. Unhealthy behaviours contribute to the development of health inequalities worldwide. The link between perceived risk and successful health behaviour change is inconclusive, particularly in vulnerable populations. This may be attributed to inattention to culture. The synthesis strategy of theory building guided the process using three methods: (1) a systematic review of literature published between 2000-2011 targeting perceived risk in vulnerable populations; (2) qualitative and (3) quantitative data from a study of Samoan Pacific Islanders at high risk of cardiovascular disease and diabetes. Main concepts of this theory include risk attention, appraisal processes, cognition, and affect. Overarching these concepts is health-world view: cultural ways of knowing, beliefs, values, images, and ideas. This theory proposes the following: (1) risk attention varies based on knowledge of the health risk in the context of health-world views; (2) risk appraisals are influenced by affect, health-world views, cultural customs, and protocols that intersect with the health risk; (3) strength of cultural beliefs, values, and images (cultural identity) mediate risk attention and risk appraisal influencing the likelihood that persons will engage in health-promoting behaviours that may contradict cultural customs/protocols. Interventions guided by a culturally sensitive mid-range theory may improve behaviour-related health inequalities in vulnerable populations. The synthesis strategy is an intensive process for developing a culturally sensitive mid-range theory. Testing of the theory will ascertain its usefulness for reducing health inequalities in vulnerable groups. © 2012 Blackwell Publishing Ltd.
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.
NASA Astrophysics Data System (ADS)
Dittkrist, K.-M.; Mordasini, C.; Klahr, H.; Alibert, Y.; Henning, T.
2014-07-01
Context. Several recent studies have found that planet migration in adiabatic disks differs significantly from migration in isothermal disks. Depending on the thermodynamic conditions, that is, the effectiveness of radiative cooling, and on the radial surface density profile, planets migrate inward or outward. Clearly, this will influence the semimajor-axis-to-mass distribution of planets predicted by population-synthesis simulations. Aims: Our goal is to study the global effects of radiative cooling, viscous torque desaturation, gap opening, and stellar irradiation on the tidal migration of a synthetic planet population. Methods: We combined results from several analytical studies and 3D hydrodynamic simulations in a new semi-analytical migration model for the application in our planet population synthesis calculations. Results: We find a good agreement of our model with torques obtained in 3D radiative hydrodynamic simulations. A typical disk has three convergence zones to which migrating planets move from the in- and outside. This strongly affects the migration behavior of low-mass planets. Interestingly, this leads to a slow type II like migration behavior for low-mass planets captured in these zones even without an ad hoc migration rate reduction factor or a yet-to-be-defined halting mechanism. This means that the new prescription of migration that includes nonisothermal effects makes the previously widely used artificial migration rate reduction factor obsolete. Conclusions: Outward migration in parts of a disk helps some planets to survive long enough to become massive. The convergence zones lead to potentially observable accumulations of low-mass planets at certain semimajor axes. Our results indicate that more studies of the mass at which the corotation torque saturates are needed since its value has a main impact on the properties of planet populations. Appendices A and B are available in electronic form at http://www.aanda.org
Synthesis of noise effects on wildlife populations
DOT National Transportation Integrated Search
2004-09-01
This report contains a summary of ongoing work on the effects of noise on wildlife populations. There is a paucity of information on the response of invertebrates to noise, particularly the levels likely to be encountered along roads. Significant pop...
TEACH: An Ethogram-Based Method to Observe and Record Teaching Behavior
ERIC Educational Resources Information Center
Kline, Michelle Ann
2017-01-01
Teaching has attracted growing research attention in studies of human and animal behavior as a crucial behavior that coevolved with human cultural capacities. However, the synthesis of data on teaching across species and across human populations has proven elusive because researchers use a variety of definitions and methods to approach the topic.…
ERIC Educational Resources Information Center
Yeo, Seungsoo
2010-01-01
The purpose of this synthesis was to examine the relationship between Curriculum-Based Measurement (CBM) and statewide achievement tests in reading. A multilevel meta-analysis was used to calculate the correlation coefficient of the population for 27 studies that met the inclusion criteria. Results showed an overall large correlation coefficient…
Testing Feedback Models with Nearby Star Forming Regions
NASA Astrophysics Data System (ADS)
Doran, E.; Crowther, P.
2012-12-01
The feedback from massive stars plays a crucial role in the evolution of galaxies. Accurate modelling of this feedback is essential in understanding distant star forming regions. Young nearby, high mass (> 104 M⊙) clusters such as R136 (in the 30 Doradus region) are ideal test beds for population synthesis since they host large numbers of spatially resolved massive stars at a pre-supernovae stage. We present a quantitative comparison of empirical calibrations of radiative and mechanical feedback from individual stars in R136, with instantaneous burst predictions from the popular Starburst99 evolution synthesis code. We find that empirical results exceed predictions by factors of ˜3-9, as a result of limiting simulations to an upper limit of 100 M⊙. 100-300 M⊙ stars should to be incorporated in population synthesis models for high mass clusters to bring predictions into close agreement with empirical results.
Hansen, Amy C.; Kock, Tobias J.; Hansen, Gabriel S.
2017-08-07
The U.S. Army Corps of Engineers (USACE) operates the Willamette Valley Project (Project) in northwestern Oregon, which includes a series of dams, reservoirs, revetments, and fish hatcheries. Project dams were constructed during the 1950s and 1960s on rivers that supported populations of spring Chinook salmon (Oncorhynchus tshawytscha), winter steelhead (O. mykiss), and other anadromous fish species in the Willamette River Basin. These dams, and the reservoirs they created, negatively affected anadromous fish populations. Efforts are currently underway to improve passage conditions within the Project and enhance populations of anadromous fish species. Research on downstream fish passage within the Project has occurred since 1960 and these efforts are documented in numerous reports and publications. These studies are important resources to managers in the Project, so the USACE requested a synthesis of existing literature that could serve as a resource for future decision-making processes. In 2016, the U.S. Geological Survey conducted an extensive literature review on downstream fish passage studies within the Project. We identified 116 documents that described studies conducted during 1960–2016. Each of these documents were obtained, reviewed, and organized by their content to describe the state-of-knowledge within four subbasins in the Project, which include the North Santiam, South Santiam, McKenzie, and Middle Fork Willamette Rivers. In this document, we summarize key findings from various studies on downstream fish passage in the Willamette Project. Readers are advised to review specific reports of interest to insure that study methods, results, and additional considerations are fully understood.
Stochasticity in the signalling network of a model microbe
NASA Astrophysics Data System (ADS)
Bischofs, Ilka; Foley, Jonathan; Battenberg, Eric; Fontaine-Bodin, Lisa; Price, Gavin; Wolf, Denise; Arkin, Adam
2007-03-01
The soil dwelling bacterium Bacillus subtilis is an excellent model organism for studying stochastic stress response induction in an isoclonal population. Subjected to the same stressor cells undergo different cell fates, including sporulation, competence, degradative enzyme synthesis and motility. For example, under conditions of nutrient deprivation and high cell density only a portion of the cell population forms an endospore. Here we use a combined experimental and theoretical approach to study stochastic sporulation induction in Bacillus subtilis. Using several fluorescent reporter strains we apply time lapse fluorescent microscopy in combination with quantitative image analysis to study cell fate progression on a single cell basis and elucidate key noise generators in the underlying cellular network.
Assessment of Cardiovascular Disease Risk in South Asian Populations
Hussain, S. Monira; Oldenburg, Brian; Zoungas, Sophia; Tonkin, Andrew M.
2013-01-01
Although South Asian populations have high cardiovascular disease (CVD) burden in the world, their patterns of individual CVD risk factors have not been fully studied. None of the available algorithms/scores to assess CVD risk have originated from these populations. To explore the relevance of CVD risk scores for these populations, literature search and qualitative synthesis of available evidence were performed. South Asians usually have higher levels of both “classical” and nontraditional CVD risk factors and experience these at a younger age. There are marked variations in risk profiles between South Asian populations. More than 100 risk algorithms are currently available, with varying risk factors. However, no available algorithm has included all important risk factors that underlie CVD in these populations. The future challenge is either to appropriately calibrate current risk algorithms or ideally to develop new risk algorithms that include variables that provide an accurate estimate of CVD risk. PMID:24163770
Fuentes, Catalina; Castillo, Joel; Vila, Jose; Nilsson, Lars
2018-06-01
The use of polymers for the delivery of drugs has increased dramatically in the last decade. To ensure the desired properties and functionality of such substances, adequate characterization in terms of the molar mass (M) and size is essential. The aim of this study was to evaluate the changes in the M and size of PVP-b-PAMPS when the amounts of the synthesis reactants in the two-step radical reaction were varied. The determination of the M and size distributions was performed by an asymmetric flow field-flow fractionation (AF4) system connected to multiangle light scattering (MALS) and differential refractive index (dRI) detectors. The results show that the M of the polymers varies depending on the relative amounts of the reactants and that AF4-MALS-dRI is a powerful characterization technique for analyzing polymers. Using AF4, it was possible to separate the product of the first radical reaction (PVP-CTA) into two populations. The first population had an elongated, rod-like or random coil conformation, and the second had a conformation corresponding to homogeneous spheres or a microgel structure. PVP-b-PAMPS had only one population, which had a rod-like conformation. The molar masses of PVP-CTA and PVP-b-PAMPS found in this study were higher than those reported in previous studies.
,; van Manen, Frank T.; Costello, Cecily M.; Haroldson, Mark A.; Bjornlie, Daniel D.; Ebinger, Michael R.; Gunther, Kerry A.; Mahalovich, Mary Frances; Thompson, Daniel J.; Higgs, Megan D.; Irvine, Kathryn M.; Legg, Kristin; Tyers, Daniel B.; Landenburger, Lisa; Cain, Steven L.; Frey, Kevin L.; Aber, Bryan C.; Schwartz, Charles C.
2013-01-01
The Yellowstone grizzly bear (Ursus arctos) was listed as a threatened species in 1975 (Federal Register 40 FR:31734-31736). Since listing, recovery efforts have focused on increasing population size, improving habitat security, managing bear mortalities, and reducing bear-human conflicts. The Interagency Grizzly Bear Committee (IGBC; partnership of federal and state agencies responsible for grizzly bear recovery in the lower 48 states) and its Yellowstone Ecosystem Subcommitte (YES; federal, state, county, and tribal partners charged with recovery of grizzly bears in the Greater Yelowston Ecosystem [GYE]) tasked the Interagency Grizzly Bear Study Team to provide information and further research relevant to three concerns arising from the 9th Circuit Court of Appeals November 2011 decision: 1) the ability of grizzly bears as omnivores to find alternative foods to whitebark pine seeds; 2) literature to support their conclusions; and 3) the non-intuitive biological reality that impacts can occur to individuals without causing the overall population to decline. Specifically, the IGBC and YES requested a comprehensive synthesis of the current state of knowledge regarding whitebark pinbe decline and individual and population-level responses of grizzly bears to changing food resources in the GYE. This research was particularly relevant to grizzly bear conservation given changes in the population trajectory observed during the last decade.
Birds and burns of the interior West: descriptions, habitats, and management in western forests.
Victoria Saab; William Block; Robin Russell; John Lehmkuhl; Lisa Bate; Rachel White
2007-01-01
This publication provides information about prescribed fire effects on habitats and populations of birds of the interior West and a synthesis of existing information on bird responses to fire across North America. Our literature synthesis indicated that aerial, ground, and bark insectivores favored recently burned habitats, whereas foliage gleaners preferred unburned...
Elk monitoring in Mount Rainier and Olympic national parks: 2008-2011 synthesis report
Jenkins, Kurt J.; Griffin, Paul C.; Happe, Patricia J.; Reid, Mason E.; Vales, David J.; Moeller, Barbara J.; Tirhe, Michelle; McCorquodale, Scott; Beirne, Katherine; Boetsch, John; Baccus, William; Lubow, Bruce C.
2015-01-01
We continue to develop and improve the DO-S model for application to OLYM summer surveys. In the next synthesis report, we will update findings with additional data following the 2015 field season, based on 8 years of survey results; it will be a more complete analysis of elk population trends.
Flow cytometric measurement of total DNA and incorporated halodeoxyuridine
Dolbeare, Frank A.; Gray, Joe W.
1988-01-01
A method for the simultaneous flow cytometric measurement of the total DNA content and the level of DNA synthesis in normal and malignant cells is disclosed. The sensitivity of the method allows a study of cell cycle traverse rates for large scale cell populations as well as single cell measurements. A DNA stain such as propidium iodide or Hoechst 33258 is used as the probe for the measurement of total DNA content and a monoclonal antibody reactive with a DNA precursor such as halodeoxy-uridine (HdU), more specifically bromodeoxyuridine (BrdU) is used as a probe for the measurement of HdU or BrdU uptake by the cells as a measure of DNA synthesis.
Grison, Claire M; Renard, Brice-Loïc; Grison, Claude
2014-02-01
2-Keto-3-deoxy-D-erythro-hexonic acid (KDG) is the key intermediate metabolite of the Entner Doudoroff (ED) pathway. A simple, efficient and stereoselective synthesis of KDG isopropyl ester is described in five steps from 2,3-O-isopropylidene-D-threitol with an overall yield of 47%. KDG isopropyl ester is studied as an attractive marker of a functional Entner Doudoroff pathway. KDG isopropyl ester is used to promote growth of ammonium producing bacterial strains, showing interesting features in the remediation of heavy-metal polluted soils. Copyright © 2013 Elsevier Inc. All rights reserved.
Fungus-mediated biological synthesis of gold nanoparticles: potential in detection of liver cancer
Chauhan, Arun; Zubair, Swaleha; Tufail, Saba; Sherwani, Asif; Sajid, Mohammad; Raman, Suri C; Azam, Amir; Owais, Mohammad
2011-01-01
Background Nanomaterials are considered to be the pre-eminent component of the rapidly advancing field of nanotechnology. However, developments in the biologically inspired synthesis of nanoparticles are still in their infancy and consequently attracting the attention of material scientists throughout the world. Keeping in mind the fact that microorganism-assisted synthesis of nanoparticles is a safe and economically viable prospect, in the current study we report Candida albicans-mediated biological synthesis of gold nanoparticles. Methods and results Transmission electron microscopy, atomic force microscopy, and various spectrophotometric analyses were performed to characterize the gold nanoparticles. The morphology of the synthesized gold particles depended on the abundance of C. albicans cytosolic extract. Transmission electron microscopy, nanophox particle analysis, and atomic force microscopy revealed the size of spherical gold nanoparticles to be in the range of 20–40 nm and nonspherical gold particles were found to be 60–80 nm. We also evaluated the potential of biogenic gold nanoparticles to probe liver cancer cells by conjugating them with liver cancer cell surface-specific antibodies. The antibody-conjugated gold particles were found to bind specifically to the surface antigens of the cancer cells. Conclusion The antibody-conjugated gold particles synthesized in this study could successfully differentiate normal cell populations from cancerous cells. PMID:22072868
Robinson, Jude; Wiggers, John
2016-01-01
Objective To thematically synthesise primary qualitative studies of the barriers, motivators and enablers of smoke-free homes (SFHs). Design Systematic review and thematic synthesis. Data sources Searches of MEDLINE, EBM Reviews (Cochrane Database of Systematic Reviews), PsycINFO, Global Health, CINAHL, Web of Science, Informit and EMBASE, combining terms for families, households and vulnerable populations; SFH and secondhand smoke; and qualitative research, were supplemented by searches of PhD theses, key authors, specialist journals and reference lists. Study selection We included 22 articles, reporting on 18 studies, involving 646 participants. Inclusion criteria: peer-reviewed; English language; published from 1990 onwards (to week 3 of April 2014); used qualitative data collection methods; explored participants’ perspectives of home smoking behaviours; and the barriers, motivators and enablers to initiating and/or maintaining a SFH. Data extraction 1 of 3 authors extracted data with checking by a second. Data synthesis A thematic synthesis was performed to develop 7 core analytic themes: (1) knowledge, awareness and risk perception; (2) agency and personal skills/attributes; (3) wider community norms and personal moral responsibilities; (4) social relationships and influence of others; (5) perceived benefits, preferences and priorities; (6) addiction and habit; (7) practicalities. Conclusions This synthesis highlights the complexity faced by many households in having a SFH, the practical, social, cultural and personal issues that need to be addressed and balanced by households, and that while some of these are common across study settings, specific social and cultural factors play a critical role in shaping household smoking behaviours. The findings can inform policy and practice and the development of interventions aimed at increasing SFHs. Trial registration number CRD42014014115. PMID:26988351
ERIC Educational Resources Information Center
Laubach, Stephen A.
2013-01-01
Ecological ideas have been manifested in diverse ways in American high schools since the early twentieth century. Core scientific concepts in ecology--the study of the relationship between organisms and their environment--include adaptations, plant succession, ecosystem ecology, and population ecology. This dissertation argues, however, that there…
Cuomo, Belinda M; Vaz, Sharmila; Lee, Elinda Ai Lim; Thompson, Craig; Rogerson, Jessica M; Falkmer, Torbjorn
2017-05-01
Sleep problems are common in children with autism spectrum disorder (ASD). This meta-synthesis collated eight previously published systematic reviews examining the efficacy of sleep interventions in children with ASD in an attempt to present a clear analysis of trialed interventions. The collated reviews consider five major groups of sleep interventions for children with ASD: melatonin therapy, pharmacologic treatments other than melatonin, behavioral interventions, parent education/education programs, and alternative therapies (massage therapy, aromatherapy, and multivitamin and iron supplementation). These eight reviews were based on 38 original studies and address the efficacy of interventions across 17 sleep problem domains. The results of this meta-synthesis suggest that no single intervention is effective across all sleep problems in children with ASD. However, melatonin, behavioral interventions, and parent education/education program interventions appear the most effective at ameliorating multiple domains of sleep problems compared with other interventions. Due to the heterogeneous causative factors and presentations of disordered sleep, further research into the effectiveness of sleep interventions may target specific phenotypic subgroups rather than a broad analysis across the general ASD population. Similarly, future research needs to consider the efficacy of different polytherapeutic approaches in order to provide clinicians with evidence to inform best practice. In the meantime, this review supports clinicians' decision making for a majority of the identified sleep problems in the ASD population. © 2017 Pharmacotherapy Publications, Inc.
Evolutionary synthesis of simple stellar populations. Colours and indices
NASA Astrophysics Data System (ADS)
Kurth, O. M.; Fritze-v. Alvensleben, U.; Fricke, K. J.
1999-07-01
We construct evolutionary synthesis models for simple stellar populations using the evolutionary tracks from the Padova group (1993, 1994), theoretical colour calibrations from \\cite[Lejeune et al. (1997, 1998)]{lejeune} and fit functions for stellar atmospheric indices from \\cite[Worthey et al. (1994)]{worthey}. A Monte-Carlo technique allows us to obtain a smooth time evolution of both broad band colours in UBVRIK and a series of stellar absorption features for Single Burst Stellar Populations (SSPs). We present colours and indices for SSPs with ages from 1 \\ 10(9) yrs to 1.6 \\ 10(10) yrs and metallicities [M/H]=-2.3, -1.7, -0.7, -0.4, 0.0 and 0.4. Model colours and indices at an age of about a Hubble time are in good agreement with observed colours and indices of the Galactic and M 31 GCs.
Disclosure of domestic violence in mental health settings: A qualitative meta-synthesis
Trevillion, Kylee; Hughes, Bryony; Feder, Gene; Borschmann, Rohan; Oram, Siân
2014-01-01
Little is known about how psychiatric services respond to service users’ experiences of domestic violence. This qualitative meta-synthesis examined the healthcare experiences and expectations of mental health service users experiencing domestic violence. Twenty-two biomedical, social science, grey literature databases and websites were searched, supplemented by citation tracking and expert recommendations. Qualitative studies which included mental health service users (aged ≥ 16 years) with experiences of domestic violence were eligible for inclusion. Two reviewers independently extracted data from included papers and assessed quality. Findings from primary studies were combined using meta-synthesis techniques. Twelve studies provided data on 140 female and four male mental health service users. Themes were generally consistent across studies. Overarching theoretical constructs included the role of professionals in identifying domestic violence and facilitating disclosures, implementing personalized care and referring appropriately. Mental health services often failed to identify and facilitate disclosures of domestic violence, and to develop responses that prioritized service users’ safety. Mental health services were reported to give little consideration to the role of domestic violence in precipitating or exacerbating mental illness and the dominance of the biomedical model and stigma of mental illness were found to inhibit effective responses. Mental health services often fail to adequately address the violence experienced by mental health service users. This meta-synthesis highlights the need for mental health services to establish appropriate strategies and responses to domestic violence to ensure optimal care of this vulnerable population. PMID:25137109
Kothapalli, Kumar S. D.; Ye, , Kaixiong; Gadgil, Maithili S.; Carlson, Susan E.; O’Brien, Kimberly O.; Zhang, Ji Yao; Park, Hui Gyu; Ojukwu, Kinsley; Zou, James; Hyon, Stephanie S.; Joshi, Kalpana S.; Gu, Zhenglong; Keinan, Alon; Brenna, J.Thomas
2016-01-01
Long chain polyunsaturated fatty acids (LCPUFA) are bioactive components of membrane phospholipids and serve as substrates for signaling molecules. LCPUFA can be obtained directly from animal foods or synthesized endogenously from 18 carbon precursors via the FADS2 coded enzyme. Vegans rely almost exclusively on endogenous synthesis to generate LCPUFA and we hypothesized that an adaptive genetic polymorphism would confer advantage. The rs66698963 polymorphism, a 22-bp insertion–deletion within FADS2, is associated with basal FADS1 expression, and coordinated induction of FADS1 and FADS2 in vitro. Here, we determined rs66698963 genotype frequencies from 234 individuals of a primarily vegetarian Indian population and 311 individuals from the US. A much higher I/I genotype frequency was found in Indians (68%) than in the US (18%). Analysis using 1000 Genomes Project data confirmed our observation, revealing a global I/I genotype of 70% in South Asians, 53% in Africans, 29% in East Asians, and 17% in Europeans. Tests based on population divergence, site frequency spectrum, and long-range haplotype consistently point to positive selection encompassing rs66698963 in South Asian, African, and some East Asian populations. Basal plasma phospholipid arachidonic acid (ARA) status was 8% greater in I/I compared with D/D individuals. The biochemical pathway product–precursor difference, ARA minus linoleic acid, was 31% and 13% greater for I/I and I/D compared with D/D, respectively. This study is consistent with previous in vitro data suggesting that the insertion allele enhances n-6 LCPUFA synthesis and may confer an adaptive advantage in South Asians because of the traditional plant-based diet practice. PMID:27188529
Fernández-Escalada, Manuel; Zulet-González, Ainhoa; Gil-Monreal, Miriam; Zabalza, Ana; Ravet, Karl; Gaines, Todd; Royuela, Mercedes
2017-01-01
A key enzyme of the shikimate pathway, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS; EC 2.5.1.19), is the known target of the widely used herbicide glyphosate. Glyphosate resistance in Amaranthus palmeri, one of the most troublesome weeds in agriculture, has evolved through increased EPSPS gene copy number. The aim of this work was to study the pleiotropic effects of (i) EPSPS increased transcript abundance due to gene copy number variation (CNV) and of (ii) glyphosate application on the aromatic amino acid (AAA) and branched chain amino acid (BCAA) synthesis pathways. Hydroponically grown glyphosate sensitive (GS) and glyphosate resistant (GR) plants were treated with glyphosate 3 days after treatment. In absence of glyphosate treatment, high EPSPS gene copy number had only a subtle effect on transcriptional regulation of AAA and BCAA pathway genes. In contrast, glyphosate treatment provoked a general accumulation of the transcripts corresponding to genes of the AAA pathway leading to synthesis of chorismate in both GS and GR. After chorismate, anthranilate synthase transcript abundance was higher while chorismate mutase transcription showed a small decrease in GR and remained stable in GS, suggesting a regulatory branch point in the pathway that favors synthesis toward tryptophan over phenylalanine and tyrosine after glyphosate treatment. This was confirmed by studying enzyme activities in vitro and amino acid analysis. Importantly, this upregulation was glyphosate dose dependent and was observed similarly in both GS and GR populations. Glyphosate treatment also had a slight effect on the expression of BCAA genes but no general effect on the pathway could be observed. Taken together, our observations suggest that the high CNV of EPSPS in A. palmeri GR populations has no major pleiotropic effect on the expression of AAA biosynthetic genes, even in response to glyphosate treatment. This finding supports the idea that the fitness cost associated with EPSPS CNV in A. palmeri may be limited. PMID:29201035
Real-Time Estimation of Small-Area Populations with Human Biomarkers in Sewage
A totally new approach is conceptualized for measuring small-area human populations by using biomarkers in sewage. The basis for the concept (SCIM: Sewage Chemical-Information Mining) is supported by a comprehensive examination and synthesis of data published across several disc...
Lourenço, O; Fonseca, A M; Paiva, A; Arosa, F A; Taborda-Barata, L
2006-01-01
CD8+ T suppressor cells may play a role in immunoregulation. Recent studies have characterized this population by the lack of the CD28 molecule. These CD8+CD28 T cells differ phenotypically and functionally from CD8 + CD28 + T cells. Little is known about CD8 + CD28 cells in atopy. Our aim was to analyze the phenotype and functional properties of CD8 + CD28T cells in atopic and non-atopic individuals. Peripheral blood mononuclear cells (PBMC) were obtained after density gradient centrifugation. CD8 + CD28 and CD8 + CD28 + T cells were isolated using immunomagnetic beads. Relative percentages of these cells and expression of several phenotypic markers were analyzed by flow cytometry. Proliferation was assessed by thymidine incorporation in isolated populations and in co-cultures with PBMC using Dermatophagoides pteronyssinus as stimulus. Cytokine synthesis was evaluated in culture supernatants by cytometric bead array. The relative percentages of CD8+CD28 T cells and their phenotypic expression in atopic and non-atopic volunteers were not significantly different. However, CD8 + CD28 T cells showed greater proliferation than did CD8+CD28+ T cells when stimulated with D. pteronyssinus, although cytokine synthesis patterns were similar. CD8+CD28 co-cultures with PBMC showed greater proliferation than CD8+CD28+ T cell co-cultures, but cytokine synthesis patterns were not different. Our data confirm phenotypic and functional differences between CD28+ and CD28 T cells, irrespective of atopic status. Purified human CD8+CD28 T cells, freshly isolated from peripheral blood, do not have suppressor properties on allergen-specific proliferation or on cytokine synthesis in PBMC.
Colour Counts: Sunlight and Skin Type as Drivers of Vitamin D Deficiency at UK Latitudes.
Webb, Ann R; Kazantzidis, Andreas; Kift, Richard C; Farrar, Mark D; Wilkinson, Jack; Rhodes, Lesley E
2018-04-07
Sunlight exposure, with resulting cutaneous synthesis, is a major source of vitamin D for many, while dietary intake is low in modern diets. The constitutive pigment in skin determines skin type, observed as white, brown, or black skin. The melanin pigment absorbs ultraviolet radiation (UVR) and protects underlying skin from damage caused by UVR. It also reduces the UVR available for vitamin D synthesis in the skin. It has been shown that the white-skinned population of the UK are able to meet their vitamin D needs with short, daily lunchtime exposures to sunlight. We have followed the same methodology, based on a 10-year UK all-weather UVR climatology, observation (sun exposure, diet, vitamin D status), and UVR intervention studies with Fitzpatrick skin type V (brown) adults, to determine whether sunlight at UK latitudes could provide an adequate source of vitamin D for this section of the population. Results show that to meet vitamin D requirements, skin type V individuals in the UK need ~25 min daily sunlight at lunchtime, from March to September. This makes several assumptions, including that forearms and lower legs are exposed June-August; only exposing hands and face at this time is inadequate. For practical and cultural reasons, enhanced oral intake of vitamin D should be considered for this population.
Delonay, Aaron J.; Chojnacki, Kimberly A.; Jacobson, Robert B.; Albers, Janice L.; Braaten, Patrick J.; Bulliner, Edward A.; Elliott, Caroline M.; Erwin, Susannah O.; Fuller, David B; Haas, Justin D.; Ladd, Hallie L.A.; Mestl, Gerald E.; Papoulias, Diana M.; Wildhaber, Mark L.
2016-01-20
Scientific understanding of the ecological requirements of pallid sturgeon has increased almost exponentially in the last two decades, and efforts are now turning from understanding fundamental biology of the species to quantifying how population dynamics relate to potential management actions. Progress in developing the science needed to inform management actions on the Missouri River may benefit from continuation of monitoring of reproductive cycles, reproductive movements, growth, and survival of telemetry tagged adults, increased emphasis on focused, complementary field and laboratory studies of factors influencing early life history, implementation of studies to resolve the role of food limitations in growth, survival, and reproductive condition, and implementation of studies designed specifically to parameterize models linking management to populations.
2013-01-01
Background The need to reduce smoking rates is a recognised public health policy issue in many countries. The workplace offers a potential context for offering smokers’ programmes and interventions to assist smoking cessation or reduction. A qualitative evidence synthesis of employees’ views about such programmes might explain why some interventions appear effective and others not, and can be used to develop evidence-based interventions for this population and setting. Methods A qualitative evidence synthesis of primary research exploring employees’ views about workplace interventions to encourage smoking cessation, including both voluntary programmes and passive interventions, such as restrictions or bans. The method used was theory-based “best fit” framework synthesis. Results Five relevant theories on workplace smoking cessation were identified and used as the basis for an a priori framework. A comprehensive literature search, including interrogation of eight databases, retrieved 747 unique citations for the review. Fifteen primary research studies of qualitative evidence were found to satisfy the inclusion criteria. The synthesis produced an evidence-based conceptual model explaining employees’ experiences of, and preferences regarding, workplace smoking interventions. Conclusion The synthesis suggests that workplace interventions should employ a range of different elements if they are to prove effective in reducing smoking among employees. This is because an employee who feels ready and able to change their behaviour has different needs and preferences from an employee who is not at that stage. Only a multi-faceted intervention can satisfy the requirements of all employees. PMID:24274158
Dental occlusion and temporomandibular disorders.
Stone, J Caitlin; Hannah, Andrew; Nagar, Nathan
2017-10-27
Data sourcesMedline, Scopus and Google Scholar.Study selectionTwo reviewers selected studies independently. English language clinical studies assessing the association between temporomandibular disorders (TMD) and features of dental occlusion were considered.Data extraction and synthesisStudy quality was assessed based on the Newcastle-Ottawa Scale (NOS) and a narrative synthesis was presented.ResultsIn all 25 studies (17 case-control, eight comparative) were included. Overall there was a high variability between occlusal features and TMD diagnosis. Findings were consistent with a lack of clinically relevant association between TMD and dental occlusion. Only two studies were associated with TMD in the majority (≥50%) of single variable analyses in patient populations. Only mediotrusive interferences are associated with TMD in the majority of multiple variable analyses.ConclusionsThe findings support the absence of a disease-specific association, there is no ground to hypothesise a major role for dental occlusion in the pathophysiology of TMDs. Dental clinicians are thus encouraged to move forward and abandon the old-fashioned gnathological paradig.
2013-01-01
Background Resistance to traditional insecticides represents a threat to the control of disease vectors. The insect growth regulators (IGR) are a potential alternative to control mosquitoes, including resistant populations. The chitin synthesis inhibitors (CSI) are IGRs, which interfere with the insect molting process and represent one major class of compounds against Aedes aegypti populations resistant to the larvicide organophosphate temephos. In the present study, we evaluated the efficacy of the CSI triflumuron on Culex quinquefasciatus, Aedes albopictus and against several Ae. aegypti field populations. Methods The efficacy of triflumuron, against Cx. quinquefasciatus and Ae. albopictus was evaluated with laboratory strains through dose–response assays. Additionaly, this CSI was tested against seven Ae. aegypti field populations exhibiting distinct resistance levels to both temephos and the pyrethroid deltamethrin. Aedes aegypti populations were exposed to both a dose that inhibits 99% of the adult emergence of mosquitoes from the susceptible reference strain, Rockefeller, (EI99 = 3.95 μg/L) and the diagnostic dose (DD), corresponding to twice the EI99. Results Our results indicate that triflumuron was effective in emergence inhibition (EI) of Cx. quinquefasciatus (EI50= 5.28 μg/L; EI90= 12.47 μg/L) and Ae. albopictus (EI50= 1.59 μg/L; EI90= 2.63 μg/L). Triflumuron was also effective against seven Ae. aegypti Brazilian populations resistant to both temephos and deltamethrin. Exposure of all the Ae. aegypti populations to the triflumuron EI99 of the susceptible reference strain, Rockefeller, resulted in complete inhibition of adult emergence, suggesting no cross-resistance among traditional insecticides and this CSI. However, a positive correlation between temephos resistance and tolerance to triflumuron was observed. Conclusion The results suggest that triflumuron represents a potential tool for the control of disease vectors in public health. Nevertheless, they point to the need of constant monitoring of the susceptibility status of vector populations to CSIs. PMID:23557173
Yen, Irene H.; Flood, Johnna Fandel; Thompson, Hannah; Anderson, Lynda A.; Wong, Geoff
2015-01-01
Objective The objective of this study was to determine the environmental features that best support aging in place. Method We conducted a realist synthesis, a theory-driven interpretive method of evidence synthesis, of 120+ articles (published 1991–2011) that attempts to explain how place may influence older adults’ decisions about mobility (e.g., physical activity). We developed an initial program theory, reviewed the literature, identified outcomes, analyzed and synthesized patterns, and created a final program theory. Results Safety was a central mechanism, serving as one of the bridges between environmental components (e.g., connectivity, aesthetics, retail and services) and decisions about mobility. Population density, sidewalk presence, and park proximity did not emerge as key factors. Discussion Safety considerations are one of the most prominent influences of older adults’ decisions about mobility. Street connectivity, pedestrian access and transit, and retail and services were also important. These factors are amenable to change and can help promote mobility for older adults. PMID:24788714
Liu, Jj; Davidson, E; Bhopal, Rs; White, M; Johnson, Mrd; Netto, G; Deverill, M; Sheikh, A
2012-01-01
There is now a considerable body of evidence revealing that a number of ethnic minority groups in the UK and other economically developed countries experience disproportionate levels of morbidity and mortality compared with the majority white European-origin population. Across these countries, health-promoting approaches are increasingly viewed as the long-term strategies most likely to prove clinically effective and cost-effective for preventing disease and improving health outcomes in those with established disease. To identify, appraise and interpret research on the approaches employed to maximise the cross-cultural appropriateness and effectiveness of health promotion interventions for smoking cessation, increasing physical activity and improving healthy eating for African-, Chinese- and South Asian-origin populations. Two national conferences; seven databases of UK guidelines and international systematic reviews of health promotion interventions aimed at the general population, including the Clinical Evidence, National Institute for Health and Clinical Excellence and Scottish Intercollegiate Guidelines Network databases (1950-2009); 11 databases of research on adapted health promotion interventions for ethnic minority populations, including BIOSIS, EMBASE and MEDLINE (1950-2009); and in-depth qualitative interviews with a purposive sample of researchers and health promoters. Theoretically based, mixed-methods, phased programme of research that involved user engagement, systematic reviews and qualitative interviews, which were integrated through a realist synthesis. Following a launch conference, two reviewers independently identified and extracted data from guidelines and systematic reviews on the effectiveness of interventions for the general population and any guidance offered in relation to how to interpret this evidence for ethnic minority populations. Data were thematically analysed. Reviewers then independently identified and critically appraised studies of adapted interventions and summarised data to assess feasibility, acceptability, equity, clinical effectiveness and cost-effectiveness. Interviews were transcribed, coded and thematically analysed. The quantitative and qualitative data were then synthesised using a realist framework to understand better how adapted interventions work and to assess implementation considerations and prioritise future research. Our preliminary findings were refined through discussion and debate at an end-of-study national user engagement conference. Initial user engagement emphasised the importance of extending this work beyond individual-centred behavioural interventions to also include examination of community- and ecological-level interventions; however, individual-centred behavioural approaches dominated the 15 relevant guidelines and 111 systematic reviews we identified. The most consistent evidence of effectiveness was for pharmacological interventions for smoking cessation. This body of work, however, provided scant evidence on the effectiveness of these interventions for ethnic minority groups. We identified 173 reports of adapted health promotion interventions, the majority of which focused on US-based African Americans. This body of evidence was used to develop a 46-item Typology of Adaptation and a Programme Theory of Adapted Health Promotion Interventions. Only nine empirical studies directly compared the effectiveness of culturally adapted interventions with standard health promotion interventions, these failing to yield any consistent evidence; no studies reported on cost-effectiveness. The 26 qualitative interviews highlighted the need to extend thinking on ethnicity from conventional dimensions to more contextual considerations. The realist synthesis enabled the production of a decision-making tool (RESET) to support future research. The lack of robust evidence of effectiveness for physical activity and healthy-eating interventions in the general population identified at the outset limited the comparative synthesis work we could undertake in the latter phases. Furthermore, the majority of studies undertaking an adapted intervention were conducted within African American populations; this raises important questions about the generalisability of findings to, for example, a UK context and other ethnic minority groups. Lastly, given our focus on three health areas and three populations, we have inevitably excluded many studies of adapted interventions for other health topics and other ethnic minority populations. There is currently a lack of evidence on how best to deliver smoking cessation, physical activity and healthy eating-related health promotion interventions to ethnic minority populations. Although culturally adapting interventions can increase salience, acceptability and uptake, there is as yet insufficient evidence on the clinical effectiveness or cost-effectiveness of these adapted approaches. More head-to-head comparisons of adapted compared with standard interventions are warranted. The Typology of Adaptation, Programme Theory of Adapted Health Promotion Interventions and RESET tool should help researchers to develop more considered approaches to adapting interventions than has hitherto been the case. The National Institute for Health Research Health Technology Assessment programme.
The relationship between ultraviolet radiation exposure and vitamin D status.
Engelsen, Ola
2010-05-01
This paper reviews the main factors influencing the synthesis of vitamin D, with particular focus on ultraviolet radiation exposure. On the global level, the main source of vitamin D is the sun. The effect of solar radiation on vitamin D synthesis depends to some extent on the initial vitamin D levels. At moderate to high latitudes, diet becomes an increasingly important source of vitamin D due to decreased solar intensity and cold temperatures, which discourage skin exposure. During the mid-winter season, these factors result in decreased solar radiation exposure, hindering extensively the synthesis of vitamin D in these populations.
ERIC Educational Resources Information Center
Nugent, William R.
2017-01-01
Meta-analysis is a significant methodological advance that is increasingly important in research synthesis. Fundamental to meta-analysis is the presumption that effect sizes, such as the standardized mean difference (SMD), based on scores from different measures are comparable. It has been argued that population observed score SMDs based on scores…
Newly Reported Hypertension after Military Combat: Deployment in a Large Population-based Study
2009-11-01
myocardial infarction and other cardiovascular risk,1 the underlying role of deployment- induced stress or combat-related violence on hypertension is not...well established. Stress is postulated to increase blood pressure through the release of corticoids and inhibition of prostaglandin synthesis, which... exercise in individuals with and without cardiovascular disease: benefits, rationale, safety, and prescription–an advisory from the Committee on Exercise
The effectiveness and cost of home care: an information synthesis.
Hedrick, S C; Inui, T S
1986-01-01
The effect of home care on patient outcomes and costs of care has been controversial. This information synthesis summarizes results from studies of home care using experimental or quasi-experimental designs, explicitly including judgments of methodologic soundness in weighing the results. In 12 studies of programs targeted at chronically ill populations, home care services appear to have no impact on mortality, patient functioning, or nursing home placements. Across studies, these services either have no effect on hospitalization or tend to increase the number of hospital days; ambulatory care utilization may be increased by 40 percent. The cost of care either is not affected or is actually increased by 15 percent. The critical need at present is for better-designed studies to test the effects of different types of home care, targeted at various types of patients, on the outcomes assessed in the existing studies, as well as on other important outcomes such as family finances, quality of life, and quality of care. PMID:3512486
Distribution of compact object mergers around galaxies
NASA Astrophysics Data System (ADS)
Bulik, T.; Belczyński, K.; Zbijewski, W.
1999-09-01
Compact object mergers are one of the favoured models of gamma ray bursts (GRB). Using a binary population synthesis code we calculate properties of the population of compact object binaries; e.g. lifetimes and velocities. We then propagate them in galactic potentials and find their distribution in relation to the host.
Variance in binary stellar population synthesis
NASA Astrophysics Data System (ADS)
Breivik, Katelyn; Larson, Shane L.
2016-03-01
In the years preceding LISA, Milky Way compact binary population simulations can be used to inform the science capabilities of the mission. Galactic population simulation efforts generally focus on high fidelity models that require extensive computational power to produce a single simulated population for each model. Each simulated population represents an incomplete sample of the functions governing compact binary evolution, thus introducing variance from one simulation to another. We present a rapid Monte Carlo population simulation technique that can simulate thousands of populations in less than a week, thus allowing a full exploration of the variance associated with a binary stellar evolution model.
COMPARING MID-INFRARED GLOBULAR CLUSTER COLORS WITH POPULATION SYNTHESIS MODELS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barmby, P.; Jalilian, F. F.
2012-04-15
Several population synthesis models now predict integrated colors of simple stellar populations in the mid-infrared bands. To date, the models have not been extensively tested in this wavelength range. In a comparison of the predictions of several recent population synthesis models, the integrated colors are found to cover approximately the same range but to disagree in detail, for example, on the effects of metallicity. To test against observational data, globular clusters (GCs) are used as the closest objects to idealized groups of stars with a single age and single metallicity. Using recent mass estimates, we have compiled a sample ofmore » massive, old GCs in M31 which contain enough stars to guard against the stochastic effects of small-number statistics, and measured their integrated colors in the Spitzer/IRAC bands. Comparison of the cluster photometry in the IRAC bands with the model predictions shows that the models reproduce the cluster colors reasonably well, except for a small (not statistically significant) offset in [4.5] - [5.8]. In this color, models without circumstellar dust emission predict bluer values than are observed. Model predictions of colors formed from the V band and the IRAC 3.6 and 4.5 {mu}m bands are redder than the observed data at high metallicities and we discuss several possible explanations. In agreement with model predictions, V - [3.6] and V - [4.5] colors are found to have metallicity sensitivity similar to or slightly better than V - K{sub s}.« less
Willingness to Participate in Clinical Trials among Patients of Chinese Heritage: A Meta-Synthesis
Limkakeng, Alexander; Phadtare, Amruta; Shah, Jatin; Vaghasia, Meenakshi; Wei, Ding Ying; Shah, Anand; Pietrobon, Ricardo
2013-01-01
Background Subjects of Chinese heritage have been found to participate in clinical research at lower rates than other groups despite growing in numbers as a population. While much research has examined research participants' motivation, there has not been a comprehensive synthesis of this information with respect to participants of Chinese descent. We sought to identify the factors that promote and hinder participation in clinical research among participants of Chinese heritage. Methodology/Principal Findings We conducted a systematic review of the literature in Pubmed, OpenJGATE, SCIRUS, and COCHRANE databases and performed a meta-synthesis of retrieved articles. We extracted qualitative data, such as quotes to identify emerging themes. We identified five studies that met our selection criteria. Of them, only one (1/5) was conducted in China while other studies involved Chinese emigrants in USA (3/5) and Singapore (1/5). Participants from China were similar to emigrants with regard to factors that either promoted or decreased research participation. Four studies reported data exclusively on Chinese subjects. Three of the five studies involved qualitative interviews while the others were conducted using a survey design. Six themes favoring research participation were identified: Personal Benefit to Participants, Financial Incentives, Participant Sense of Altruism, Family or Physician Recommendations, Advertisements, and Convenience to the Participant. Five factors were seen as a barrier to participation in clinical trials: Mistrust of Researchers, Language Barrier, Lack of Financial and Other Support, Cultural and Social Barriers, Lack of Knowledge about Clinical Trials. Conclusions/Significance Chinese heritage clinical research participants value personal benefit, financial incentives, the ability to help others, recommendations of others, advertisements, and convenience when considering clinical research participation. In addition, the establishment of trust and addressing knowledge deficits are important factors to them. Investigators seeking to optimize enrolment in these populations should incorporate these findings into their study design and subject handouts. PMID:23349672
A secondary meta-synthesis of qualitative studies of gender and access to cardiac rehabilitation.
Angus, Jan E; King-Shier, Kathryn M; Spaling, Melisa A; Duncan, Amanda S; Jaglal, Susan B; Stone, James A; Clark, Alexander M
2015-08-01
To discuss issues in the theorization and study of gender observed during a qualitative meta-synthesis of influences on uptake of secondary prevention and cardiac rehabilitation services. Women and men can equally benefit from secondary prevention/cardiac rehabilitation and there is a need to understand gender barriers to uptake. Meta-method analysis secondary to meta-synthesis. For the meta-synthesis, a systematic search was performed to identify and retrieve studies published as full papers during or after 1995 and contained: a qualitative research component wholly or in a mixed method design, extractable population specific data or themes for referral to secondary prevention programmes and adults ≥18 years. Databases searched between January 1995-31 October 2011 included: CSA Sociological Abstracts, EBSCOhost CINAHL, EBSCOhost Gender Studies, EBSCOhost Health Source Nursing: Academic Edition, EBSCOhost SPORTDiscus, EBSCOhost SocINDEX. Studies were reviewed against inclusion/exclusion criteria. Included studies were subject to quality appraisal and standardized data extraction. Of 2264 screened articles, 69 were included in the meta-method analysis. Only four studies defined gender or used gender theories. Findings were mostly presented as inherently the characteristic of gendered worldviews of participants. The major themes suggest a mismatch between secondary prevention/cardiac rehabilitation services and consumers' needs, which are usually portrayed as differing according to gender but may also be subject to intersecting influences such as age or socioeconomic status. There is a persistent lack of theoretically informed gender analysis in qualitative literature in this field. Theory-driven gender analysis will improve the conceptual clarity of the evidence base for gender-sensitive cardiac rehabilitation programme development. © 2015 John Wiley & Sons Ltd.
Non-native fishes in Florida freshwaters: a literature review and synthesis
Schofield, Pamela J.; Loftus, William F.
2015-01-01
Non-native fishes have been known from freshwater ecosystems of Florida since the 1950s, and dozens of species have established self-sustaining populations. Nonetheless, no synthesis of data collected on those species in Florida has been published until now. We searched the literature for peer-reviewed publications reporting original data for 42 species of non-native fishes in Florida that are currently established, were established in the past, or are sustained by human intervention. Since the 1950s, the number of non-native fish species increased steadily at a rate of roughly six new species per decade. Studies documented (in decreasing abundance): geographic location/range expansion, life- and natural-history characteristics (e.g., diet, habitat use), ecophysiology, community composition, population structure, behaviour, aquatic-plant management, and fisheries/aquaculture. Although there is a great deal of taxonomic uncertainty and confusion associated with many taxa, very few studies focused on clarifying taxonomic ambiguities of non-native fishes in the State. Most studies were descriptive; only 15 % were manipulative. Risk assessments, population-control studies and evaluations of effects of non-native fishes were rare topics for research, although they are highly valued by natural-resource managers. Though some authors equated lack of data with lack of effects, research is needed to confirm or deny conclusions. Much more is known regarding the effects of lionfish (Pterois spp.) on native fauna, despite its much shorter establishment time. Natural-resource managers need biological and ecological information to make policy decisions regarding non-native fishes. Given the near-absence of empirical data on effects of Florida non-native fishes, and the lengthy time-frames usually needed to collect such information, we provide suggestions for data collection in a manner that may be useful in the evaluation and prediction of non-native fish effects.
Clokie, Samuel J H; Lau, Pierre; Kim, Hyun Hee; Coon, Steven L; Klein, David C
2012-07-20
MicroRNAs (miRNAs) play a broad range of roles in biological regulation. In this study, rat pineal miRNAs were profiled for the first time, and their importance was evaluated by focusing on the main function of the pineal gland, melatonin synthesis. Massively parallel sequencing and related methods revealed the miRNA population is dominated by a small group of miRNAs as follows: ~75% is accounted for by 15 miRNAs; miR-182 represents 28%. In addition to miR-182, miR-183 and miR-96 are also highly enriched in the pineal gland, a distinctive pattern also found in the retina. This effort also identified previously unrecognized miRNAs and other small noncoding RNAs. Pineal miRNAs do not exhibit a marked night/day difference in abundance with few exceptions (e.g. 2-fold night/day differences in the abundance of miR-96 and miR-182); this contrasts sharply with the dynamic 24-h pattern that characterizes the pineal transcriptome. During development, the abundance of most pineal gland-enriched miRNAs increases; however, there is a marked decrease in at least one, miR-483. miR-483 is a likely regulator of melatonin synthesis, based on the following. It inhibits melatonin synthesis by pinealocytes in culture; it acts via predicted binding sites in the 3"-UTR of arylalkylamine N-acetyltransferase (Aanat) mRNA, the penultimate enzyme in melatonin synthesis, and it exhibits a developmental profile opposite to that of Aanat transcripts. Additionally, a miR-483 targeted antagonist increased melatonin synthesis in neonatal pinealocytes. These observations support the hypothesis that miR-483 suppresses Aanat mRNA levels during development and that the developmental decrease in miR-483 abundance promotes melatonin synthesis.
Stolee, Paul; Elliott, Jacobi; McNeil, Heather; Boscart, Veronique; Heckman, George A; Hutchinson, Rebecca; Hedley, Margaret; Glouberman, Sholom; Judd, Maria
2015-01-01
Introduction While patient and citizen engagement has been recognised as a crucial element in healthcare reform, limited attention has been paid to how best to engage seniors—the fastest growing segment of the population and the largest users of the healthcare system. To improve the healthcare services for this population, seniors and their families need to be engaged as active partners in healthcare decision-making, research and planning. This synthesis aims to understand the underlying context and mechanisms needed to achieve meaningful engagement of older adults in healthcare decision-making, research and planning. Methods and analysis The CHOICE Knowledge Synthesis Project: Choosing Healthcare Options by Involving Canada's Elderly aims to address this issue by synthesising current knowledge on patient, family, and caregiver engagement. A realist synthesis will support us to learn from other patient and citizen engagement initiatives, from previous research, and from seniors, families and caregivers themselves. The synthesis will guide development or adaptation of a framework, leading to the development of best practice guidelines and recommendations for engagement of older people and their families and caregivers in clinical decision-making, healthcare delivery, planning and research. Ethics and dissemination The components of this protocol involving consultation with patients or caregivers have received ethics clearance from the University of Waterloo, Office of Research Ethics (ORE#19094). After completion of the project, we will amalgamate the information collected into a knowledge synthesis report which will include best practice guidelines and recommendations for patient, family and caregiver engagement in clinical and health system planning and research contexts. Results Will be further disseminated to citizens, clinicians, researchers and policymakers with the help of our partners. Trial registration number CRD42015024749. PMID:26534730
Reweighting anthropometric data using a nearest neighbour approach.
Kumar, Kannan Anil; Parkinson, Matthew B
2018-07-01
When designing products and environments, detailed data on body size and shape are seldom available for the specific user population. One way to mitigate this issue is to reweight available data such that they provide an accurate estimate of the target population of interest. This is done by assigning a statistical weight to each individual in the reference data, increasing or decreasing their influence on statistical models of the whole. This paper presents a new approach to reweighting these data. Instead of stratified sampling, the proposed method uses a clustering algorithm to identify relationships between the detailed and reference populations using their height, mass, and body mass index (BMI). The newly weighted data are shown to provide more accurate estimates than traditional approaches. The improved accuracy that accompanies this method provides designers with an alternative to data synthesis techniques as they seek appropriate data to guide their design practice.Practitioner Summary: Design practice is best guided by data on body size and shape that accurately represents the target user population. This research presents an alternative to data synthesis (e.g. regression or proportionality constants) for adapting data from one population for use in modelling another.
Wu, Shuyan; Yu, Pak-Lam; Wheeler, Dave; Flint, Steve
2018-06-19
The aim of this study was to determine the gene expression associated with the persistence of a Listeria monocytogenes stationary phase population when facing lethal nisin treatment METHODS: RNA Seq analysis was used for gene expression profiling of the persister cells in rich medium (persister TN) compared with untreated cells (non-persister).The results were confirmed using RT PCR. Functional genes associated with the persister populations were identified in multiple systems, such as heat shock related stress response, cell wall synthesis, ATP-binding cassette (ABC) transport system, phosphotransferase system (PTS system), and SOS/DNA repair. This study pointed to genetic regulation of persister cells exposed to lethal nisin and provides some insight into possible mechanisms of impeding bacterial persistence. Copyright © 2018. Published by Elsevier Ltd.
Higginbottom, Gina M A; Morgan, Myfanwy; Dassanayake, Jayantha; Eyford, Helgi; Alexandre, Mirande; Chiu, Yvonne; Forgeron, Joan; Kocay, Deb
2012-05-31
Canada's diverse society and statutory commitment to multiculturalism means that the synthesis of knowledge related to the health care experiences of immigrants is essential to realize the health potential for future Canadians. Although concerns about the maternity experiences of immigrants in Canada are relatively new, recent national guidelines explicitly call for tailoring of services to user needs. We are therefore assessing the experiences of immigrant women in Canada accessing maternity-care services. We are focusing on: 1) accessibility and acceptability (as an important dimension of access) to maternity-care services as perceived and experienced by immigrant women, and 2) the birth and postnatal outcomes of these women. The aim of this study is to use a narrative synthesis, incorporating both a systematic review using narrative synthesis of reports of empirical research (qualitative, quantitative, and mixed-method designs), and a literature review of non-empirically based reports, both of which include 'grey' literature. The study aims to provide stakeholders with perspectives on maternity-care services as experienced by immigrant women. To achieve this, we are using integrated knowledge translation, partnering with key stakeholders to ensure topic relevancy and to tailor recommendations for effective translation into future policy and practice/programming. Two search phases and a three-stage selection process are being conducted (database search retrieved 1487 hits excluding duplicates) to provide evidence to contribute jointly to both the narrative synthesis and the non-empirical literature review. The narrative synthesis will be informed by the previous framework published in 2006 by Popay et al., using identified tools for each of its four elements. The non-empirical literature review will build upon the narrative-synthesis findings and/or identify omissions or gaps in the empirical research literature. The integrated knowledge translation plan will ensure that key messages are delivered in an audience-specific manner to optimize their effect on policy and practice change throughout the health service, and the public health, immigration and community sectors. Narrative-synthesis methods of systematic review facilitate understanding and acknowledgement of the broader influences of theoretical and contextual variables, such as race, gender, socioeconomic status, and geographical location. They also enable understanding of the shaping of differences between reported outcomes and study designs related to childbearing populations, and the development and implementation of maternity services and health interventions across diverse settings. Number 2185.
Ultraviolet light exposure, skin cancer risk and vitamin D production.
Rivas, Miguel; Rojas, Elisa; Araya, María C; Calaf, Gloria M
2015-10-01
The danger of overexposure to solar ultraviolet radiation has been widely reviewed since the 1980s due to the depletion of the ozone layer. However, the benefits of mild exposure of the skin to ultraviolet (UV) light have not been widely investigated. Numerous reports have demonstrated that an association exists between low light exposure to the sun, non-melanoma skin cancer and a lack of vitamin D synthesis. As vitamin D synthesis in the body depends on skin exposure to UVB radiation from the sun (wavelength, 290-320 nm), experimental measurements for this type of solar radiation are important. The present study analyzed data obtained from a laboratory investigating UV radiation from the sun at the University of Tarapacá (Arica, Chile), where systematic experimental UVB measurements had been performed using a calibrated biometer instrument since 2006. These data were compared with skin cancer data from the local population. The results demonstrated that the incidence of skin cancer systematically increased from 7.4 to 18.7 in men and from 10.0 to 21.7 in women between 2000 and 2006 in Arica, respectively; this increase may be due to multiple factors, including the lack of adequate levels of vitamin D in risk groups such as post-menopausal women and senior age. This marked increase may also be due to the high levels of UV radiation measured in this region throughout the year. However, it is not certain that the local population has adequate vitamin D levels, nor that their skin has been predominantly exposed to artificial light that does not allow adequate vitamin D synthesis. Thus, the current study presents the association between skin type IV, the time to induce solar erythema and the time required to produce 1,000 international units of vitamin D.
Ultraviolet light exposure, skin cancer risk and vitamin D production
RIVAS, MIGUEL; ROJAS, ELISA; ARAYA, MARÍA C.; CALAF, GLORIA M.
2015-01-01
The danger of overexposure to solar ultraviolet radiation has been widely reviewed since the 1980s due to the depletion of the ozone layer. However, the benefits of mild exposure of the skin to ultraviolet (UV) light have not been widely investigated. Numerous reports have demonstrated that an association exists between low light exposure to the sun, non-melanoma skin cancer and a lack of vitamin D synthesis. As vitamin D synthesis in the body depends on skin exposure to UVB radiation from the sun (wavelength, 290–320 nm), experimental measurements for this type of solar radiation are important. The present study analyzed data obtained from a laboratory investigating UV radiation from the sun at the University of Tarapacá (Arica, Chile), where systematic experimental UVB measurements had been performed using a calibrated biometer instrument since 2006. These data were compared with skin cancer data from the local population. The results demonstrated that the incidence of skin cancer systematically increased from 7.4 to 18.7 in men and from 10.0 to 21.7 in women between 2000 and 2006 in Arica, respectively; this increase may be due to multiple factors, including the lack of adequate levels of vitamin D in risk groups such as post-menopausal women and senior age. This marked increase may also be due to the high levels of UV radiation measured in this region throughout the year. However, it is not certain that the local population has adequate vitamin D levels, nor that their skin has been predominantly exposed to artificial light that does not allow adequate vitamin D synthesis. Thus, the current study presents the association between skin type IV, the time to induce solar erythema and the time required to produce 1,000 international units of vitamin D. PMID:26622830
Revealing Companions to Nearby Stars with Astrometric Acceleration
2012-07-01
objects, such as stellar -mass black holes or failed supernova (Gould & Salim 2002). Table 4 includes a sample of some of the most interesting dis...knowledge of binary and multiple star statistics is needed for the study of star formation, for stellar population synthesis, for predicting the...frequency of supernovae, blue stragglers, X-ray binaries, etc. The statistical properties of binaries strongly depend on stellar mass. Only for nearby solar
Treating Offenders with Mental Illness: A Research Synthesis
Morgan, Robert D.; Flora, David B.; Kroner, Daryl G.; Mills, Jeremy F.; Varghese, Femina; Steffan, Jarrod S.
2011-01-01
The purpose of this research synthesis was to examine treatment effects across studies of the service providers to offenders with mental illness. Meta-analytic techniques were applied to 26 empirical studies obtained from a review of 12,154 research documents. Outcomes of interest in this review included measures of both psychiatric and criminal functioning. Although meta-analytic results are based on a small sample of available studies, results suggest interventions with offenders with mental illness effectively reduced symptoms of distress, improving offender’s ability to cope with their problems, and resulted in improved behavioral markers including institutional adjustment and behavioral functioning. Furthermore, interventions specifically designed to meet the psychiatric and criminal justice needs of offenders with mental illness have shown to produce significant reductions in psychiatric and criminal recidivism. Finally, this review highlighted admission policies and treatment strategies (e.g., use of homework), which produced the most positive benefits. Results of this research synthesis are directly relevant for service providers in both criminal justice and mental health systems (e.g., psychiatric hospitals) as well as community settings by informing treatment strategies for the first time, which are based on empirical evidence. In addition, the implications of these results to policy makers tasked with the responsibility of designating services for this special needs population are highlighted. PMID:22471384
Nielsen, Annemette Ljungdalh; Jervelund, Signe Smith; Villadsen, Sarah Fredsted; Vitus, Kathrine; Ditlevsen, Kia; TØrslev, Mette Kirstine; Kristiansen, Maria
2017-03-01
This paper examines the importance of recruitment site in relation to the recruitment of ethnic minorities into health research. It presents a synthesis of experiences drawn from six interlinked Danish studies which applied different methods and used healthcare facilities and educational settings as sites for recruitment. Inspired by interpretive reviewing, data on recruitment methods from the different studies were synthesized with a focus on the various levels of recruitment success achieved. This involved an iterative process of comparison, analysis and discussion of experiences among the researchers involved. Success in recruitment seemed to depend partly on recruitment site. Using healthcare facilities as the recruitment site and healthcare professionals as gatekeepers was less efficient than using schools and employees from educational institutions. Successful study designs also depended on the possibility of singling out specific locations with a high proportion of the relevant ethnic minority target population. The findings, though based on a small number of cases, indicate that health professionals and healthcare institutions, despite their interest in high-quality health research into all population groups, fail to facilitate research access to some of the most disadvantaged groups, who need to be included in order to understand the mechanisms behind health disparities. This happens despite the genuine wish of many healthcare professionals to help facilitate such research. In this way, the findings indirectly emphasize the specific challenge of accessing more vulnerable and sick groups in research studies.
NASA Astrophysics Data System (ADS)
Falfushynska, Halina I.; Phan, Tuan; Sokolova, Inna M.
2016-12-01
Global climate change (GCC) can negatively affect freshwater ecosystems. However, the degree to which freshwater populations can acclimate to long-term warming and the underlying molecular mechanisms are not yet fully understood. We used the cooling water discharge (CWD) area of a power plant as a model for long-term warming. Survival and molecular stress responses (expression of molecular chaperones, antioxidants, bioenergetic and protein synthesis biomarkers) to experimental warming (20-41 °C, +1.5 °C per day) were assessed in invasive clams Corbicula fluminea from two pristine populations and a CWD population. CWD clams had considerably higher (by ~8-12 °C) lethal temperature thresholds than clams from the pristine areas. High thermal tolerance of CWD clams was associated with overexpression of heat shock proteins HSP70, HSP90 and HSP60 and activation of protein synthesis at 38 °C. Heat shock response was prioritized over the oxidative stress response resulting in accumulation of oxidative lesions and ubiquitinated proteins during heat stress in CWD clams. Future studies should determine whether the increase in thermal tolerance in CWD clams are due to genetic adaptation and/or phenotypic plasticity. Overall, our findings indicate that C. fluminea has potential to survive and increase its invasive range during warming such as expected during GCC.
NASA Astrophysics Data System (ADS)
Forgan, Duncan; Rice, Ken
2013-07-01
Recently, the gravitational instability (GI) model of giant planet and brown dwarf formation has been revisited and recast into what is often referred to as the "tidal downsizing" hypothesis. The fragmentation of self-gravitating protostellar discs into gravitationally bound embryos - with masses of a few to tens of Jupiter masses, at semi major axes above 30 - 40 AU - is followed by a combination of grain sedimentation inside the embryo, radial migration towards the central star and tidal disruption of the embryo's upper layers. The properties of the resultant object depends sensitively on the timescales upon which each process occurs. Therefore, GI followed by tidal downsizing can theoretically produce objects spanning a large mass range, from terrestrial planets to giant planets and brown dwarfs. Whether such objects can be formed in practice, and what proportions of the observed population they would represent, requires a more involved statistical analysis. We present a simple population synthesis model of star and planet formation via GI and tidal downsizing. We couple a semi-analytic model of protostellar disc evolution to analytic calculations of fragmentation, initial embryo mass, grain growth and sedimentation, embryo migration and tidal disruption. While there are key pieces of physics yet to be incorporated, it represents a first step towards a mature statistical model of GI and tidal downsizing as a mode of star and planet formation. We show results from four runs of the population synthesis model, varying the opacity law and the strength of migration, as well as investigating the effect of disc truncation during the fragmentation process.
On the rarity of X-ray binaries with Wolf-Rayet donors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Linden, T.; Valsecchi, F.; Kalogera, V.
The paucity of High mass X-Ray binaries (HMXB) consisting of a neutron star (NS) accretor and Wolf-Rayet (WR) donor has long been at odds with expectations from population synthesis studies indicating that these systems should survive as the evolved offspring of the observed HMXB population. This tension is particularly troubling in light of recent observations uncovering a preponderance of HMXBs containing loosely bound Be donors which would be expected to naturally evolve into WR-HMXBs. Reconciling the unexpectedly large population of Be-HMXBs with the lack of observed WR-HMXB sources thus serves to isolate the dynamics of CE physics from other binarymore » evolution parameters. We find that binary mergers during CE events must be common in order to resolve tension between these observed populations. Furthermore, future observations which better constrain the background population of loosely bound O/B-NS binaries are likely to place significant constraints on the efficiency of CE removal.« less
Miettinen, T A; Gylling, H; Nissinen, M J
2011-10-01
To study the whole-body cholesterol metabolism in man, cholesterol synthesis and absorption need to be measured. Because of the complicated methods of the measurements, new approaches were developed including the analysis of serum non-cholesterol sterols. In current lipidologic papers and even in intervention studies, serum non-cholesterol sterols are frequently used as surrogate markers of cholesterol metabolism without any validation to the absolute metabolic variables. The present review compares serum non-cholesterol sterols with absolute measurements of cholesterol synthesis and absorption in published papers to find out whether the serum markers are valid indicators of cholesterol metabolism in various conditions. During statin treatment, during interventions of dietary fat, and in type 2 diabetes the relative and absolute variables of cholesterol synthesis and absorption were frequently but not constantly correlated with each other. In some occasions, especially in subjects with apolipoprotein E3/4 and E4/4 phenotypes, the relative metabolic markers were even more sensitive than the absolute ones to reflect changes in cholesterol metabolism during dietary interventions. Even in general population at very high absorption the homeostasis of cholesterol metabolism is disturbed damaging the validity of the serum markers. It is worth using several instead of only one precursor and absorption sterol marker for making conclusions of altered synthesis or absorption of cholesterol, and even then the presence of at least some absolute measurement is valuable. During consumption of plant sterol-enriched diets and in situations of interfered cholesterol homeostasis the relative markers do not adequately reflect cholesterol metabolism. Accordingly, the validity of the relative markers of cholesterol metabolism should not be considered as self-evident. Copyright © 2011 Elsevier B.V. All rights reserved.
Toxicity of nalidixic acid on candida albicans, Saccharomyces cerevisiae, and Kluyveromyces lactis.
Sobieski, R J; Brewer, A R
1976-03-01
The antibacterial drug nalidixic acid (Nal) can suppress the growth of Candida albicans at levels of the drug normally found in urine. Growth suppression increases as drug levels are increased, and Nal also causes a similar proportional inhibition of the synthesis of all cellular macromolecules. However, growth temperature (25 versus 37 C) and the divalent cations Mg(2+) and Mn(2+) can increase C. albicans resistance to Nal. Also, nitrogen depletion of Candida shows that Nal-treated and untreated cells exhibit no difference in leucine uptake during readaptation to nitrogen. In Nal-treated, nitrogen-starved cells, ribonucleic acid and deoxyribonucleic acid (DNA) biosynthesis are less affected than in unstarved Nal-treated cells, but of the two nucleic acids DNA synthesis is the most affected. Nal-resistant strains of C. albicans exhibit a slight toxicity for macromolecular synthesis. Nal treatment of a synchronized population of Saccharomyces cerevisiae results in an increase in the culture mean doubling time of, at most, 20%, but Nal causes the loss of synchronous cell division. With a synchronized population of Kluyveromyces lactis, Nal causes an increase in the mean doubling time of upwards of 300%, with synchrony of cell division being maintained. It is known that S. cerevisiae asynchronously synthesizes mitochondrial DNA during the cell cycle, whereas with K. lactis it is synchronous. Thus, with C. albicans Nal toxicity is dependent both on the dose and the physiological state of the cell. Furthermore, Nal inhibits growth of yeast with synchronous mitochondrial DNA synthesis more adversely than yeast with asynchronous mitochondrial DNA synthesis.
Role of adrenal hormones and prostaglandins in the control of mouse thymocytes lysis.
Durant, S; Seillan, C; Duval, D; Homo-Delarche, F
1984-01-01
The cytolytic actions of glucocorticoids and of agents increasing cyclic AMP were studied in vitro in thymocyte suspensions isolated from adrenalectomized or hydrocortisone-treated mice. Although considered as corticoresistant cells, the thymocytes isolated from hydrocortisone-treated mice were lysed to the same extent although more slowly in vitro by dexamethasone than whole thymocyte populations (i.e. corticosensitive cells). Moreover, these two cell populations were shown to contain comparable amounts of glucocorticoid receptors and to be almost equally sensitive to the metabolic effects of glucocorticoids when measured by inhibition of RNA and DNA synthesis. Studies performed with corticosensitive cells showed that prostaglandin E2, isoproterenol and dibutyrilcyclic AMP were also able to induce cell lysis and that, isoproterenol and dexamethasone exerted additive cytolytic action in vitro. In vivo experiments showed also an additive effect of steroids and isoproterenol on thymus atrophy. In contrast, cells isolated from hydrocortisone-treated animals were not sensitive to the cytotoxic action of prostaglandin E2, isoproterenol and dibutyril cyclic AMP. This difference between the two populations was not associated with any difference in the responsiveness of adenylate cyclase as determined following isoproterenol-induced accumulation of cyclic AMP. The cytolytic action of dexamethasone but also that of prostaglandin E2 and isoproterenol, could be blocked in the presence of cycloheximide, an inhibitor of protein synthesis, thus suggesting that glucocorticoids and agents increasing cyclic AMP control the synthesis of some proteins involved in the triggering of cell lysis. Among the hypotheses proposed to explain the differences between in vitro and in vivo sensitivity of lymphoid cell to glucocorticoids, it was suggested that the drug may in vivo indirectly control the viability or the proliferation of thymocytes through the release of other mediators. We have shown that in vivo injection of hydrocortisone induces an accumulation of fatty acids in the whole thymus gland but not in the isolated thymocytes. Since exogenous fatty acids exert cytolytic actions on isolated thymocytes, we suggest that glucocorticoids may exert in vivo an indirect toxic action by promoting the release of fatty acids from adipose tissue or other sources.
Point-Sampling and Line-Sampling Probability Theory, Geometric Implications, Synthesis
L.R. Grosenbaugh
1958-01-01
Foresters concerned with measuring tree populations on definite areas have long employed two well-known methods of representative sampling. In list or enumerative sampling the entire tree population is tallied with a known proportion being randomly selected and measured for volume or other variables. In area sampling all trees on randomly located plots or strips...
Binary Populations and Stellar Dynamics in Young Clusters
NASA Astrophysics Data System (ADS)
Vanbeveren, D.; Belkus, H.; Van Bever, J.; Mennekens, N.
2008-06-01
We first summarize work that has been done on the effects of binaries on theoretical population synthesis of stars and stellar phenomena. Next, we highlight the influence of stellar dynamics in young clusters by discussing a few candidate UFOs (unconventionally formed objects) like intermediate mass black holes, η Car, ζ Pup, γ2 Velorum and WR 140.
Shaw, Gregory; Lee-Barthel, Ann; Ross, Megan LR; Wang, Bing; Baar, Keith
2017-01-01
Background: Musculoskeletal injuries are the most common complaint in active populations. More than 50% of all injuries in sports can be classified as sprains, strains, ruptures, or breaks of musculoskeletal tissues. Nutritional and/or exercise interventions that increase collagen synthesis and strengthen these tissues could have an important effect on injury rates. Objective: This study was designed to determine whether gelatin supplementation could increase collagen synthesis. Design: Eight healthy male subjects completed a randomized, double-blinded, crossover-design study in which they consumed either 5 or 15 g of vitamin C–enriched gelatin or a placebo control. After the initial drink, blood was taken every 30 min to determine amino acid content in the blood. A larger blood sample was taken before and 1 h after consumption of gelatin for treatment of engineered ligaments. One hour after the initial supplement, the subjects completed 6 min of rope-skipping to stimulate collagen synthesis. This pattern of supplementation was repeated 3 times/d with ≥6 h between exercise bouts for 3 d. Blood was drawn before and 4, 24, 48, and 72 h after the first exercise bout for determination of amino-terminal propeptide of collagen I content. Results: Supplementation with increasing amounts of gelatin increased circulating glycine, proline, hydroxyproline, and hydroxylysine, peaking 1 h after the supplement was given. Engineered ligaments treated for 6 d with serum from samples collected before or 1 h after subjects consumed a placebo or 5 or 15 g gelatin showed increased collagen content and improved mechanics. Subjects who took 15 g gelatin 1 h before exercise showed double the amino-terminal propeptide of collagen I in their blood, indicating increased collagen synthesis. Conclusion: These data suggest that adding gelatin to an intermittent exercise program improves collagen synthesis and could play a beneficial role in injury prevention and tissue repair. This trial was registered at the Australian New Zealand Clinical Trials Registry as ACTRN12616001092482. PMID:27852613
Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis.
Shaw, Gregory; Lee-Barthel, Ann; Ross, Megan Lr; Wang, Bing; Baar, Keith
2017-01-01
Musculoskeletal injuries are the most common complaint in active populations. More than 50% of all injuries in sports can be classified as sprains, strains, ruptures, or breaks of musculoskeletal tissues. Nutritional and/or exercise interventions that increase collagen synthesis and strengthen these tissues could have an important effect on injury rates. This study was designed to determine whether gelatin supplementation could increase collagen synthesis. Eight healthy male subjects completed a randomized, double-blinded, crossover-design study in which they consumed either 5 or 15 g of vitamin C-enriched gelatin or a placebo control. After the initial drink, blood was taken every 30 min to determine amino acid content in the blood. A larger blood sample was taken before and 1 h after consumption of gelatin for treatment of engineered ligaments. One hour after the initial supplement, the subjects completed 6 min of rope-skipping to stimulate collagen synthesis. This pattern of supplementation was repeated 3 times/d with ≥6 h between exercise bouts for 3 d. Blood was drawn before and 4, 24, 48, and 72 h after the first exercise bout for determination of amino-terminal propeptide of collagen I content. Supplementation with increasing amounts of gelatin increased circulating glycine, proline, hydroxyproline, and hydroxylysine, peaking 1 h after the supplement was given. Engineered ligaments treated for 6 d with serum from samples collected before or 1 h after subjects consumed a placebo or 5 or 15 g gelatin showed increased collagen content and improved mechanics. Subjects who took 15 g gelatin 1 h before exercise showed double the amino-terminal propeptide of collagen I in their blood, indicating increased collagen synthesis. These data suggest that adding gelatin to an intermittent exercise program improves collagen synthesis and could play a beneficial role in injury prevention and tissue repair. This trial was registered at the Australian New Zealand Clinical Trials Registry as ACTRN12616001092482. © 2017 American Society for Nutrition.
A Literature Synthesis of Health Promotion Research in Salons and Barbershops
Linnan, Laura A.; D’Angelo, Heather; Harrington, Cherise B.
2015-01-01
Context Barbershops and beauty salons are located in all communities and frequented by diverse groups of people, making them key settings for addressing health disparities. No studies have reviewed the growing body of literature describing studies promoting health in these settings. This review summarized the literature related to promoting health within barbershops and beauty salons to inform future approaches that target diverse populations in similar settings. Evidence Acquisition We identified and reviewed published research articles describing formative research, recruitment, and health-related interventions set in beauty salons and barbershops. PubMed and other secondary search engines were searched in 2010 and again in 2013 for English-language papers indexed from 1990 through August 2013. The search yielded 110 articles, 68 of which were formerly reviewed, and 54 were eligible for inclusion. Evidence Synthesis Included articles were categorized as formative research (n=27), recruitment (n=7), or intervention (n=20). Formative research studies showed that owners, barbers/stylists, and their customers were willing participants, clarifying the feasibility of promoting health in these settings. Recruitment studies demonstrated that salon/shop owners will join research studies and can enroll customers. Among intervention studies, level of stylist/barber involvement was categorized. More than 73.3% of intervention studies demonstrated statistically significant results, targeting mostly racial/ethnic minority groups and focusing on a variety of health topics. Conclusions Barbershops and beauty salons are promising settings for reaching populations most at risk for health disparities. Although these results are encouraging, more rigorous research and evaluation of future salon- and barbershop-based interventions are needed. PMID:24768037
JunB transcription factor maintains skeletal muscle mass and promotes hypertrophy
Raffaello, Anna; Milan, Giulia; Masiero, Eva; Carnio, Silvia; Lee, Donghoon
2010-01-01
The size of skeletal muscle cells is precisely regulated by intracellular signaling networks that determine the balance between overall rates of protein synthesis and degradation. Myofiber growth and protein synthesis are stimulated by the IGF-1/Akt/mammalian target of rapamycin (mTOR) pathway. In this study, we show that the transcription factor JunB is also a major determinant of whether adult muscles grow or atrophy. We found that in atrophying myotubes, JunB is excluded from the nucleus and that decreasing JunB expression by RNA interference in adult muscles causes atrophy. Furthermore, JunB overexpression induces hypertrophy without affecting satellite cell proliferation and stimulated protein synthesis independently of the Akt/mTOR pathway. When JunB is transfected into denervated muscles, fiber atrophy is prevented. JunB blocks FoxO3 binding to atrogin-1 and MuRF-1 promoters and thus reduces protein breakdown. Therefore, JunB is important not only in dividing populations but also in adult muscle, where it is required for the maintenance of muscle size and can induce rapid hypertrophy and block atrophy. PMID:20921137
Hethcoat, Matthew G.; Chalfoun, Anna D.
2015-01-01
Synthesis and applications. We demonstrate one mechanism, that is the local augmentation of predators, by which human-induced rapid environmental change can influence the demography of local populations. Given the accelerating trajectory of global energy demands, an important next step will be to understand why the activity and/or abundance of rodent predators increased with surrounding habitat loss from energy development activities.
Sex effect on polychlorinated biphenyl concentrations in fish: a synthesis
Madenjian, C.P.
2011-01-01
Polychlorinated biphenyls (PCBs) accumulate in fish primarily via food intake, and therefore, PCBs serve as a chemical tracer for food consumption. Sex differences in PCB concentrations of fish have been attributed to the following three mechanisms: (i) females losing a substantial portion of their PCB body burden during spawning and consequently their PCB concentration is considerably reduced immediately after spawning; (ii) sex differences in habitat utilization leading to sex differences in the PCB concentrations of the prey; and (iii) sex differences in gross growth efficiency, which is defined as growth divided by the amount of food consumption needed to achieve that growth. Based on my analyses and synthesis, mechanisms (i) and (ii) operate in relatively few fish populations, but can lead to mature males having PCB concentrations two to three times higher than mature female PCB concentrations. In contrast, mechanism (iii) operates in all fish populations, but typically, mechanism (iii) results in relatively modest sex differences, with mature males only between 15 and 35% higher in PCB concentration than mature females. In summary, the study of sex differences in PCB concentrations of fish has led to insights into fish behaviour and fish physiology.
Mayatepek, E; Zelezny, R; Hoffmann, G F
2000-02-25
Cysteinyl leukotrienes (LTC(4), LTD(4), LTE(4)) are potent lipid mediators derived from arachidonate in the 5-lipoxygenase pathway. Recently, the first inborn error of leukotriene synthesis, LTC(4)-synthesis deficiency, has been identified in association with a fatal developmental syndrome. The absence of leukotrienes in cerebrospinal fluid was one of the most striking biochemical findings in this disorder. We analysed leukotrienes in cerebrospinal fluid of patients with a broad spectrum of other well-defined inborn errors of metabolism, including glutathione synthetase deficiency (n=2), Zellweger syndrome (n=3), mitochondrial disorders (n=8), fatty acid oxidation defects (n=7), organic acidurias (n=7), neurotransmitter defects (n=5) and patients with non-specific neurological symptoms, as a reference population (n=120). The concentrations of leukotrienes were not related to age. Representative percentiles were calculated as reference intervals of each leukotriene. In all patients with an inborn error of metabolism concentration of cysteinyl leukotrienes and LTB(4) did not differ from the reference group. Our results indicate that absence of cysteinyl leukotrienes (<5 pg/ml) in association with normal or increased LTB(4) (50.0-67.3 pg/ml) is pathognomonic for LTC(4)-synthesis deficiency. The unique profile of leukotrienes in cerebrospinal fluid in this new disorder is primarily related to the defect and represents a new diagnostic approach.
NASA Astrophysics Data System (ADS)
Pietrinferni, Adriano; Cassisi, Santi; Salaris, Maurizio; Castelli, Fiorella
2004-09-01
We present a large and updated stellar evolution database for low-, intermediate-, and high-mass stars in a wide metallicity range, suitable for studying Galactic and extragalactic simple and composite stellar populations using population synthesis techniques. The stellar mass range is between ~0.5 and 10 Msolar with a fine mass spacing. The metallicity [Fe/H] comprises 10 values ranging from -2.27 to 0.40, with a scaled solar metal distribution. The initial He mass fraction ranges from Y=0.245, for the more metal-poor composition, up to 0.303 for the more metal-rich one, with ΔY/ΔZ~1.4. For each adopted chemical composition, the evolutionary models have been computed without (canonical models) and with overshooting from the Schwarzschild boundary of the convective cores during the central H-burning phase. Semiconvection is included in the treatment of core convection during the He-burning phase. The whole set of evolutionary models can be used to compute isochrones in a wide age range, from ~30 Myr to ~15 Gyr. Both evolutionary models and isochrones are available in several observational planes, employing an updated set of bolometric corrections and color-Teff relations computed for this project. The number of points along the models and the resulting isochrones is selected in such a way that interpolation for intermediate metallicities not contained in the grid is straightforward; a simple quadratic interpolation produces results of sufficient accuracy for population synthesis applications.We compare our isochrones with results from a series of widely used stellar evolution databases and perform some empirical tests for the reliability of our models. Since this work is devoted to scaled solar chemical compositions, we focus our attention on the Galactic disk stellar populations, employing multicolor photometry of unevolved field main-sequence stars with precise Hipparcos parallaxes, well-studied open clusters, and one eclipsing binary system with precise measurements of masses, radii, and [Fe/H] of both components. We find that the predicted metallicity dependence of the location of the lower, unevolved main sequence in the color magnitude diagram (CMD) appears in satisfactory agreement with empirical data. When comparing our models with CMDs of selected, well-studied, open clusters, once again we were able to properly match the whole observed evolutionary sequences by assuming cluster distance and reddening estimates in satisfactory agreement with empirical evaluations of these quantities. In general, models including overshooting during the H-burning phase provide a better match to the observations, at least for ages below ~4 Gyr. At [Fe/H] around solar and higher ages (i.e., smaller convective cores) before the onset of radiative cores, the selected efficiency of core overshooting may be too high in our model, as well as in various other models in the literature. Since we also provide canonical models, the reader is strongly encouraged to always compare the results from both sets in this critical age range.
Eosinophils as a novel cell source of prostaglandin D2: autocrine role in allergic inflammation
Luna-Gomes, Tatiana; Magalhães, Kelly G; Mesquita-Santos, Fabio P.; Bakker-Abreu, Ilka; Samico, Rafaela F.; Molinaro, Raphael; Calheiros, Andrea S.; Diaz, Bruno L.; Bozza, Patrícia T.
2011-01-01
Prostaglandin (PG)D2 is a key mediator of allergic inflammatory diseases that is mainly synthesized by mast cells, which constitutively express high levels of the terminal enzyme involved in PGD2 synthesis, the hematopoietic PGD synthase (H-PGDS). Here, we investigated whether eosinophils are also able to synthesize, and therefore, supply biologically active PGD2. PGD2 synthesis was evaluated within human blood eosinophils, in vitro-differentiated mouse eosinophils, and eosinophils infiltrating inflammatory site of mouse allergic reaction. Biological function of eosinophil-derived PGD2 was studied by employing inhibitors of synthesis and activity. Constitutive expression of H-PGDS was found within non-stimulated human circulating eosinophils. Acute stimulation of human eosinophils with A23187 (0.1 – 5 μM) evoked PGD2 synthesis, which was located at the nuclear envelope and was inhibited by pre-treatment with HQL-79 (10 μM), a specific H-PGDS inhibitor. Pre-stimulation of human eosinophils with arachidonic acid (AA; 10 μM) or human eotaxin (6 nM) also enhanced HQL-79-sensitive PGD2 synthesis, which, by acting on membrane-expressed specific receptors (DP1 and DP2), displayed an autocrine/paracrine ability to trigger leukotriene (LT)C4 synthesis and lipid body biogenesis, hallmark events of eosinophil activation. In vitro-differentiated mouse eosinophils also synthesized paracrine/autocrine active PGD2 in response to AA stimulation. In vivo, at late time point of the allergic reaction, infiltrating eosinophils found at the inflammatory site appeared as an auxiliary PGD2-synthesizing cell population. Our findings reveal that eosinophils are indeed able to synthesize and secrete PGD2, hence representing during allergic inflammation an extra cell source of PGD2, which functions as an autocrine signal for eosinophil activation. PMID:22102725
Clokie, Samuel J. H.; Lau, Pierre; Kim, Hyun Hee; Coon, Steven L.; Klein, David C.
2012-01-01
MicroRNAs (miRNAs) play a broad range of roles in biological regulation. In this study, rat pineal miRNAs were profiled for the first time, and their importance was evaluated by focusing on the main function of the pineal gland, melatonin synthesis. Massively parallel sequencing and related methods revealed the miRNA population is dominated by a small group of miRNAs as follows: ∼75% is accounted for by 15 miRNAs; miR-182 represents 28%. In addition to miR-182, miR-183 and miR-96 are also highly enriched in the pineal gland, a distinctive pattern also found in the retina. This effort also identified previously unrecognized miRNAs and other small noncoding RNAs. Pineal miRNAs do not exhibit a marked night/day difference in abundance with few exceptions (e.g. 2-fold night/day differences in the abundance of miR-96 and miR-182); this contrasts sharply with the dynamic 24-h pattern that characterizes the pineal transcriptome. During development, the abundance of most pineal gland-enriched miRNAs increases; however, there is a marked decrease in at least one, miR-483. miR-483 is a likely regulator of melatonin synthesis, based on the following. It inhibits melatonin synthesis by pinealocytes in culture; it acts via predicted binding sites in the 3′-UTR of arylalkylamine N-acetyltransferase (Aanat) mRNA, the penultimate enzyme in melatonin synthesis, and it exhibits a developmental profile opposite to that of Aanat transcripts. Additionally, a miR-483 targeted antagonist increased melatonin synthesis in neonatal pinealocytes. These observations support the hypothesis that miR-483 suppresses Aanat mRNA levels during development and that the developmental decrease in miR-483 abundance promotes melatonin synthesis. PMID:22908386
Extreme Glacial Legacies: A Synthesis of the Antarctic Springtail Phylogeographic Record
McGaughran, Angela; Stevens, Mark I.; Hogg, Ian D.; Carapelli, Antonio
2011-01-01
We review current phylogeographic knowledge from across the Antarctic terrestrial landscape with a focus on springtail taxa. We describe consistent patterns of high genetic diversity and structure among populations which have persisted in glacial refugia across Antarctica over both short (<2 Mya) and long (>10 Mya) timescales. Despite a general concordance of results among species, we explain why location is important in determining population genetic patterns within bioregions. We complete our review by drawing attention to the main limitations in the field of Antarctic phylogeography, namely that the scope of geographic focus is often lacking within studies, and that large gaps remain in our phylogeographic knowledge for most terrestrial groups. PMID:26467614
T cell chronic lymphocytic leukaemia with suppressor phenotype.
Hofman, F M; Smith, D; Hocking, W
1982-01-01
The peripheral blood cells from a patient with T cell chronic lymphocytic leukaemia were examined for surface marker and functional characteristics. Eighty-91% of the peripheral blood cells formed SRBC rosettes and 22-49% possessed Fc receptors; 73% of the peripheral blood cells were reactive with the OKT8 antiserum and 61% expressed DR antigens. Response to PHA stimulation was markedly reduced, whereas allogeneic responsiveness in mixed leucocyte culture was intact. The ability of Con A-stimulated peripheral blood cells to generate suppressor activity in a mixed leucocyte reaction was deficient, whereas suppression of in vitro immunoglobulin synthesis was greater than normal. The leukaemic peripheral blood cell population expressed a T suppressor phenotype. Functional studies suggest that these cells were derived from the subset of T lymphocytes with regulatory activity for immunoglobulin synthesis as opposed to mitogenic responsiveness. PMID:6215199
A Meta-Analysis of Dunn and Dunn Model Correlational Research with Adult Populations
ERIC Educational Resources Information Center
Mangino, Christine
2004-01-01
The purpose of this investigation was to conduct a quantitative synthesis of correlational research that focused on the Dunn and Dunn Learning-Style Model and was concerned with adult populations. A total of 8,661 participants from the 47 original investigations provided 386 individual effect sizes for this meta-analysis. The mean effect size was…
Conservation assessment for the dusky Canada goose (Branta canadensis occidentalis Baird).
Robert G. Bromley; Thomas C. Rothe
2003-01-01
Dusky Canada geese compose one of the smallest populations of geese in North America and have exhibited a marked decline in the past 30 years. A comprehensive synthesis of past and current biological information on the subspecies has been compiled to provide insights into the ecology and demography of the population, as well as explore management efforts to promote...
ERIC Educational Resources Information Center
United Nations Educational, Scientific, and Cultural Organization, Bangkok (Thailand). Regional Office for Education in Asia and Oceania.
The primary objectives of this seminar was to provide concrete and diversified field experiences in functional literacy approaches, principles, methods and techniques carried out within the framework of an ongoing population education and family planning program. Included in the report are an introduction, general operational procedures…
Cordier, Christopher; Morton, Daniel; Murrison, Sarah; O'Leary-Steele, Catherine
2008-01-01
The purpose of diversity-oriented synthesis is to drive the discovery of small molecules with previously unknown biological functions. Natural products necessarily populate biologically relevant chemical space, since they bind both their biosynthetic enzymes and their target macromolecules. Natural product families are, therefore, libraries of pre-validated, functionally diverse structures in which individual compounds selectively modulate unrelated macromolecular targets. This review describes examples of diversity-oriented syntheses which have, to some extent, been inspired by the structures of natural products. Particular emphasis is placed on innovations that allow the synthesis of compound libraries that, like natural products, are skeletally diverse. Mimicking the broad structural features of natural products may allow the discovery of compounds that modulate the functions of macromolecules for which ligands are not known. The ability of innovations in diversity-oriented synthesis to deliver such compounds is critically assessed. PMID:18663392
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.
Population genetics of reef coral endosymbionts (Symbiodinium, Dinophyceae).
Thornhill, D J; Howells, E J; Wham, D C; Steury, T D; Santos, S R
2017-05-01
Symbiodinium is a diverse genus of unicellular dinoflagellate symbionts associating with various marine protists and invertebrates. Although the broadscale diversity and phylogenetics of the Symbiodinium complex is well established, there have been surprisingly few data on fine-scale population structure and biogeography of these dinoflagellates. Yet population-level processes contribute strongly to the biology of Symbiodinium, including how anthropogenic-driven global climate change impacts these symbionts and their host associations. Here, we present a synthesis of population-level characteristics for Symbiodinium, with an emphasis on how phylogenetic affinities, dynamics within and among host individuals, and a propensity towards clonality shape patterns on and across reefs. Major inferences include the following: (i) Symbiodinium populations within individual hosts are comprised mainly of cells belonging to a single or few genetic clones. (ii) Symbiont populations exhibit a mixed mode of reproduction, wherein at least one sexual recombination event occurs in the genealogy between most genotypes, but clonal propagation predominates overall. (iii) Mutualistic Symbiodinium do not perpetually persist outside their hosts, instead undergoing turnover and replacement via the continuous shedding of viable clonal cells from host individuals. (iv) Symbiont populations living in the same host, but on different reefs, are often genetically subdivided, suggesting low connectivity, adaptation to local conditions, or prolific asexual reproduction and low effective population sizes leading to disproportionate success within and among hosts. Overall, this synthesis forms a basis for future investigations of coral symbiosis ecology and evolution as well as delimitation of species boundaries in Symbiodinium and other eukaryotic microorganisms. © 2017 John Wiley & Sons Ltd.
Transdisciplinary synthesis for ecosystem science, policy and management: The Australian experience.
Lynch, A J J; Thackway, R; Specht, A; Beggs, P J; Brisbane, S; Burns, E L; Byrne, M; Capon, S J; Casanova, M T; Clarke, P A; Davies, J M; Dovers, S; Dwyer, R G; Ens, E; Fisher, D O; Flanigan, M; Garnier, E; Guru, S M; Kilminster, K; Locke, J; Mac Nally, R; McMahon, K M; Mitchell, P J; Pierson, J C; Rodgers, E M; Russell-Smith, J; Udy, J; Waycott, M
2015-11-15
Mitigating the environmental effects of global population growth, climatic change and increasing socio-ecological complexity is a daunting challenge. To tackle this requires synthesis: the integration of disparate information to generate novel insights from heterogeneous, complex situations where there are diverse perspectives. Since 1995, a structured approach to inter-, multi- and trans-disciplinary(1) collaboration around big science questions has been supported through synthesis centres around the world. These centres are finding an expanding role due to ever-accumulating data and the need for more and better opportunities to develop transdisciplinary and holistic approaches to solve real-world problems. The Australian Centre for Ecological Analysis and Synthesis (ACEAS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cummings, Jeffrey D.; Geisler, D.; Villanova, S.
The analysis of multiple populations (MPs) in globular clusters (GCs), both spectroscopically and photometrically, is key in understanding their formation and evolution. The relatively narrow Johnson U, F336W, and Stromgren and Sloan u filters have been crucial in exhibiting these MPs photometrically, but in Paper I we showed that the broader Washington C filter can more efficiently detect MPs in the test case GC NGC 1851. Additionally, In Paper I we detected a double main sequence (MS) that has not been detected in previous observations of NGC 1851. We now match this photometry to NGC 1851's published RGB abundances andmore » find that the two RGB branches observed in C generally exhibit different abundance characteristics in a variety of elements (e.g., Ba, Na, and O) and in CN band strengths, but no single element can define the two RGB branches. However, simultaneously considering [Ba/Fe] or CN strength with either [Na/Fe], [O/Fe], or CN strength can separate the two photometric RGB branches into two distinct abundance groups. Matches of NGC 1851's published SGB and HB abundances to the Washington photometry shows consistent characterizations of the MPs, which can be defined as an O-rich/N-normal population and an O-poor/N-rich population. Photometric synthesis for both the Washington C filter and the F336W filter finds that these abundance characteristics, with appropriate variations in He, can reproduce for both filters the photometric observations in both the RGB and the MS. This photometric synthesis also confirms the throughput advantages that the C filter has in detecting MPs.« less
NASA Astrophysics Data System (ADS)
Cummings, Jeffrey D.; Geisler, D.; Villanova, S.
2017-04-01
The analysis of multiple populations (MPs) in globular clusters (GCs), both spectroscopically and photometrically, is key in understanding their formation and evolution. The relatively narrow Johnson U, F336W, and Stromgren and Sloan u filters have been crucial in exhibiting these MPs photometrically, but in Paper I we showed that the broader Washington C filter can more efficiently detect MPs in the test case GC NGC 1851. Additionally, In Paper I we detected a double main sequence (MS) that has not been detected in previous observations of NGC 1851. We now match this photometry to NGC 1851's published RGB abundances and find that the two RGB branches observed in C generally exhibit different abundance characteristics in a variety of elements (e.g., Ba, Na, and O) and in CN band strengths, but no single element can define the two RGB branches. However, simultaneously considering [Ba/Fe] or CN strength with either [Na/Fe], [O/Fe], or CN strength can separate the two photometric RGB branches into two distinct abundance groups. Matches of NGC 1851's published SGB and HB abundances to the Washington photometry shows consistent characterizations of the MPs, which can be defined as an O-rich/N-normal population and an O-poor/N-rich population. Photometric synthesis for both the Washington C filter and the F336W filter finds that these abundance characteristics, with appropriate variations in He, can reproduce for both filters the photometric observations in both the RGB and the MS. This photometric synthesis also confirms the throughput advantages that the C filter has in detecting MPs.
Template-directed chemistry and the origins of the RNA world
NASA Technical Reports Server (NTRS)
Kanavarioti, Anastassia
1994-01-01
Prompted by the growing number of reports about reactions catalyzed by ribozymes, this paper summarizes mechanistic and kinetic aspects of template-directed (TD) chemistry important for the synthesis of a diverse population of polynucleotides and analogues possibly up to 100 units long. Assuming that this chemistry takes place in a microenvironment conducive to life under the constant influx of mM concentrations of activated monomeric building blocks, the proposed scenario represents a working hypothesis for the prebiotic synthesis of the RNA world.
The Effects of Stellar Dynamics on the Evolution of Young, Dense Stellar Systems
NASA Astrophysics Data System (ADS)
Belkus, H.; van Bever, J.; Vanbeveren, D.
In this paper, we report on first results of a project in Brussels in which we study the effects of stellar dynamics on the evolution of young dense stellar systems using 3 decades of expertise in massive-star evolution and our population (number and spectral) synthesis code. We highlight an unconventionally formed object scenario (UFO-scenario) for Wolf Rayet binaries and study the effects of a luminous blue variable-type instability wind mass-loss formalism on the formation of intermediate-mass black holes.
2012-01-01
Background Canada’s diverse society and statutory commitment to multiculturalism means that the synthesis of knowledge related to the health care experiences of immigrants is essential to realize the health potential for future Canadians. Although concerns about the maternity experiences of immigrants in Canada are relatively new, recent national guidelines explicitly call for tailoring of services to user needs. We are therefore assessing the experiences of immigrant women in Canada accessing maternity-care services. We are focusing on: 1) accessibility and acceptability (as an important dimension of access) to maternity-care services as perceived and experienced by immigrant women, and 2) the birth and postnatal outcomes of these women. Methods The aim of this study is to use a narrative synthesis, incorporating both a systematic review using narrative synthesis of reports of empirical research (qualitative, quantitative, and mixed-method designs), and a literature review of non-empirically based reports, both of which include ‘grey’ literature. The study aims to provide stakeholders with perspectives on maternity-care services as experienced by immigrant women. To achieve this, we are using integrated knowledge translation, partnering with key stakeholders to ensure topic relevancy and to tailor recommendations for effective translation into future policy and practice/programming. Two search phases and a three-stage selection process are being conducted (database search retrieved 1487 hits excluding duplicates) to provide evidence to contribute jointly to both the narrative synthesis and the non-empirical literature review. The narrative synthesis will be informed by the previous framework published in 2006 by Popay et al., using identified tools for each of its four elements. The non-empirical literature review will build upon the narrative-synthesis findings and/or identify omissions or gaps in the empirical research literature. The integrated knowledge translation plan will ensure that key messages are delivered in an audience-specific manner to optimize their effect on policy and practice change throughout the health service, and the public health, immigration and community sectors. Discussion Narrative-synthesis methods of systematic review facilitate understanding and acknowledgement of the broader influences of theoretical and contextual variables, such as race, gender, socioeconomic status, and geographical location. They also enable understanding of the shaping of differences between reported outcomes and study designs related to childbearing populations, and the development and implementation of maternity services and health interventions across diverse settings. PROSPERO registration Number 2185. PMID:22651573
Gomez, Luis F; Sarmiento, Rodrigo; Ordoñez, Maria Fernanda; Pardo, Carlos Felipe; de Sá, Thiago Hérick; Mallarino, Christina H; Miranda, J Jaime; Mosquera, Janeth; Parra, Diana Celmira; Reis, Rodrigo; Quistberg, Alex
2015-01-01
This study summarizes the evidence from quantitative systematic reviews that assessed the association between urban environment attributes and physical activity. It also documents sociopolitical barriers and facilitators involved in urban interventions linked with active living in the ten most populated urban settings of Latin America. The synthesis of evidence indicates that several attributes of urban environments are associated with physical activity, including land-use mix and cycling infrastructure. The documentary analysis indicated that despite the benefits and opportunities provided by the programs and existing infrastructure in the examined cities, an overall concern is the rising inequality in the coverage and distribution of the initiatives in the region. If these programs and initiatives are to achieve a real population level effect that helps to reduce health disparities, they need to examine their social and spatial distribution within the cities so they can reach underserved populations and develop to their full potential. PMID:25748111
Gomez, Luis F; Sarmiento, Rodrigo; Ordoñez, Maria Fernanda; Pardo, Carlos Felipe; de Sá, Thiago Hérick; Mallarino, Christina H; Miranda, J Jaime; Mosquera, Janeth; Parra, Diana C; Reis, Rodrigo; Quistberg, D Alex
2015-04-01
This study summarizes the evidence from quantitative systematic reviews that assessed the association between urban environment attributes and physical activity. It also documents sociopolitical barriers and facilitators involved in urban interventions linked with active living in the ten most populated urban settings of Latin America. The synthesis of evidence indicates that several attributes of urban environments are associated with physical activity, including land-use mix and cycling infrastructure. The documentary analysis indicated that despite the benefits and opportunities provided by the programs and existing infrastructure in the examined cities, an overall concern is the rising inequality in the coverage and distribution of the initiatives in the region. If these programs and initiatives are to achieve a real population level effect that helps to reduce health disparities, they need to examine their social and spatial distribution within the cities so they can reach underserved populations and develop to their full potential. Copyright © 2015 Elsevier Ltd. All rights reserved.
Identification of clinical phenotypes in knee osteoarthritis: a systematic review of the literature.
Dell'Isola, A; Allan, R; Smith, S L; Marreiros, S S P; Steultjens, M
2016-10-12
Knee Osteoarthritis (KOA) is a heterogeneous pathology characterized by a complex and multifactorial nature. It has been hypothesised that these differences are due to the existence of underlying phenotypes representing different mechanisms of the disease. The aim of this study is to identify the current evidence for the existence of groups of variables which point towards the existence of distinct clinical phenotypes in the KOA population. A systematic literature search in PubMed was conducted. Only original articles were selected if they aimed to identify phenotypes of patients aged 18 years or older with KOA. The methodological quality of the studies was independently assessed by two reviewers and qualitative synthesis of the evidence was performed. Strong evidence for existence of specific phenotypes was considered present if the phenotype was supported by at least two high-quality studies. A total of 24 studies were included. Through qualitative synthesis of evidence, six main sets of variables proposing the existence of six phenotypes were identified: 1) chronic pain in which central mechanisms (e.g. central sensitisation) are prominent; 2) inflammatory (high levels of inflammatory biomarkers); 3) metabolic syndrome (high prevalence of obesity, diabetes and other metabolic disturbances); 4) Bone and cartilage metabolism (alteration in local tissue metabolism); 5) mechanical overload characterised primarily by varus malalignment and medial compartment disease; and 6) minimal joint disease characterised as minor clinical symptoms with slow progression over time. This study identified six distinct groups of variables which should be explored in attempts to better define clinical phenotypes in the KOA population.
The impact of financial incentives on physical activity in adults: a systematic review protocol.
Luong, My-Linh Nguyen; Bennell, Kim L; Hall, Michelle; Harris, Anthony; Hinman, Rana S
2018-01-25
Most adults fail to meet global physical activity guidelines set out by the World Health Organization. In recent years, behavioural economic principles have been used to design novel interventions that increase physical activity. Immediate financial rewards, for instance, can motivate an individual to change physical activity behaviour by lowering the opportunity costs of exercise. This systematic review will summarise the evidence about the effectiveness of financial incentive interventions for improving physical activity in adults. We will search MEDLINE, Embase, Cochrane Central Register of Controlled Trials, the Cumulative Index to Nursing and Allied Health Literature, Web of Science, Scopus, PsycINFO, EconLit, SPORTDiscus, the National Health Service Economic Evaluation Database, ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform from inception using a comprehensive, electronic search strategy. The search strategy will include terms related to 'financial incentive' and 'physical activity'. Only randomised controlled trials that investigate the effect of financial incentives on physical activity in adult populations and that are written in the English language will be included. Two review authors will independently screen abstracts and titles, complete full text reviews and extract data on objective and self-reported physical activity outcomes. The authors will also assess the study quality using the Cochrane risk of bias tool and provide a systematic presentation and synthesis of the included studies' characteristics and results. If more than two studies are sufficiently similar in population, settings and interventions, we will pool the data to conduct a meta-analysis. If we are unable to perform a meta-analysis, we will conduct a narrative synthesis of the results and produce forest plots for individual studies. Our subgroup analyses will examine the differential effects of an intervention in healthy populations compared to populations with disease pathology and compare the effects of interventions using financial rewards to interventions using financial penalties. This systematic review will determine the effectiveness of positive and negative financial incentives on physical activity in adults. Findings will help inform the development of public health interventions and research in this field. PROSPERO 2017: CRD42017068263.
NASA Astrophysics Data System (ADS)
Kotulla, Ralf
2012-10-01
Over its lifespan Hubble has invested significant effort into detailed observations of galaxies both in the local and distant universe. To extract the physical information from the observed {spectro-}photometry requires detailed and accurate models. Stellar population synthesis models are frequently used to obtain stellar masses, star formation rate, galaxy ages and star formation histories. Chemical evolution models offer another valuable and complementary approach to gain insight into many of the same aspects, yet these two methods have rarely been used in combination.Our proposed next generation of galaxy evolution models will help us improve our understanding of how galaxies form and evolve. Building on GALEV evolutionary synthesis models we incorporate state-of-the-art input physics for stellar evolution of binaries and rotating stars as well as new spectral libraries well matched to the modern observational capabilities. Our improved chemical evolution model allows us to self-consistently trace abundances of individual elements, fully accounting for the increasing initial abundances of successive stellar generations. GALEV will support variable Initial Mass Functions {IMF}, enabling us to test recent observational findings of a non-universal IMF by predicting chemical properties and integrated spectra in an integrated and consistent manner.HST is the perfect instrument for testing this approach. Its wide wavelength coverage from UV to NIR enables precise SED fitting, and with its spatial resolution we can compare the inferred chemical evolution to studies of star clusters and resolved stellar populations in nearby galaxies.
Passey, Megan E; Longman, Jo M; Robinson, Jude; Wiggers, John; Jones, Laura L
2016-03-17
To thematically synthesise primary qualitative studies of the barriers, motivators and enablers of smoke-free homes (SFHs). Systematic review and thematic synthesis. Searches of MEDLINE, EBM Reviews (Cochrane Database of Systematic Reviews), PsycINFO, Global Health, CINAHL, Web of Science, Informit and EMBASE, combining terms for families, households and vulnerable populations; SFH and secondhand smoke; and qualitative research, were supplemented by searches of PhD theses, key authors, specialist journals and reference lists. We included 22 articles, reporting on 18 studies, involving 646 participants. peer-reviewed; English language; published from 1990 onwards (to week 3 of April 2014); used qualitative data collection methods; explored participants' perspectives of home smoking behaviours; and the barriers, motivators and enablers to initiating and/or maintaining a SFH. 1 of 3 authors extracted data with checking by a second. A thematic synthesis was performed to develop 7 core analytic themes: (1) knowledge, awareness and risk perception; (2) agency and personal skills/attributes; (3) wider community norms and personal moral responsibilities; (4) social relationships and influence of others; (5) perceived benefits, preferences and priorities; (6) addiction and habit; (7) practicalities. This synthesis highlights the complexity faced by many households in having a SFH, the practical, social, cultural and personal issues that need to be addressed and balanced by households, and that while some of these are common across study settings, specific social and cultural factors play a critical role in shaping household smoking behaviours. The findings can inform policy and practice and the development of interventions aimed at increasing SFHs. CRD42014014115. 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/
Rapid Monte Carlo Simulation of Gravitational Wave Galaxies
NASA Astrophysics Data System (ADS)
Breivik, Katelyn; Larson, Shane L.
2015-01-01
With the detection of gravitational waves on the horizon, astrophysical catalogs produced by gravitational wave observatories can be used to characterize the populations of sources and validate different galactic population models. Efforts to simulate gravitational wave catalogs and source populations generally focus on population synthesis models that require extensive time and computational power to produce a single simulated galaxy. Monte Carlo simulations of gravitational wave source populations can also be used to generate observation catalogs from the gravitational wave source population. Monte Carlo simulations have the advantes of flexibility and speed, enabling rapid galactic realizations as a function of galactic binary parameters with less time and compuational resources required. We present a Monte Carlo method for rapid galactic simulations of gravitational wave binary populations.
Sewall Wright, shifting balance theory, and the hardening of the modern synthesis.
Ishida, Yoichi
2017-02-01
The period between the 1940s and 1960s saw the hardening of the modern synthesis in evolutionary biology. Gould and Provine argue that Wright's shifting balance theory of evolution hardened during this period. But their account does not do justice to Wright, who always regarded selection as acting together with drift. This paper presents a more adequate account of the development of Wright's shifting balance theory, paying particular attention to his application of the theory to the geographical distribution of flower color dimorphism in Linanthus parryae. The account shows that even in the heyday of the hardened synthesis, the balance or interaction of evolutionary factors, such as drift, selection, and migration, occupied pride of place in Wright's theory, and that between the 1940s and 1970s, Wright developed the theory of isolation by distance to quantitatively represent the structure of the Linanthus population, which he argued had the kind of structure posited by his shifting balance theory. In the end, Wright arrived at a sophisticated description of the structure of the Linanthus population, where the interaction between drift and selection varied spatially. Copyright © 2016 Elsevier Ltd. All rights reserved.
Exploring Nitrilase Sequence Space for Enantioselective Catalysis†
Robertson, Dan E.; Chaplin, Jennifer A.; DeSantis, Grace; Podar, Mircea; Madden, Mark; Chi, Ellen; Richardson, Toby; Milan, Aileen; Miller, Mark; Weiner, David P.; Wong, Kelvin; McQuaid, Jeff; Farwell, Bob; Preston, Lori A.; Tan, Xuqiu; Snead, Marjory A.; Keller, Martin; Mathur, Eric; Kretz, Patricia L.; Burk, Mark J.; Short, Jay M.
2004-01-01
Nitrilases are important in the biosphere as participants in synthesis and degradation pathways for naturally occurring, as well as xenobiotically derived, nitriles. Because of their inherent enantioselectivity, nitrilases are also attractive as mild, selective catalysts for setting chiral centers in fine chemical synthesis. Unfortunately, <20 nitrilases have been reported in the scientific and patent literature, and because of stability or specificity shortcomings, their utility has been largely unrealized. In this study, 137 unique nitrilases, discovered from screening of >600 biotope-specific environmental DNA (eDNA) libraries, were characterized. Using culture-independent means, phylogenetically diverse genomes were captured from entire biotopes, and their genes were expressed heterologously in a common cloning host. Nitrilase genes were targeted in a selection-based expression assay of clonal populations numbering 106 to 1010 members per eDNA library. A phylogenetic analysis of the novel sequences discovered revealed the presence of at least five major sequence clades within the nitrilase subfamily. Using three nitrile substrates targeted for their potential in chiral pharmaceutical synthesis, the enzymes were characterized for substrate specificity and stereospecificity. A number of important correlations were found between sequence clades and the selective properties of these nitrilases. These enzymes, discovered using a high-throughput, culture-independent method, provide a catalytic toolbox for enantiospecific synthesis of a variety of carboxylic acid derivatives, as well as an intriguing library for evolutionary and structural analyses. PMID:15066841
Emke, Erik; Vughs, Dennis; Kolkman, Annemieke; de Voogt, Pim
2018-05-01
Chemical analysis of domestic wastewater can reveal the presence of illicit drugs either consumed by a population or directly discharged into the sewer system. In the search for causes of a recent malfunctioning of a small domestic wastewater treatment plant aberrantly high loads of amphetamine were observed in the influent of the plant. Direct discharges of chemical waste from illegal production sites were suspected to be the cause. Illegal manufacturing of amphetamines creates substantial amounts of chemical waste. Here we show that fly-tipping of chemical waste originating from an amphetamine synthesis in the catchment of a small sewage treatment plant resulted in failure of the treatment process. Target analysis of drugs of abuse and non-target screening using high resolution mass spectrometry provided evidence for the presence of amphetamine produced from the precursor 1-phenylpropan-2-one by the Leuckart process through specific synthesis markers. Furthermore the identity and presence of the pre-precursor 3-oxo-2-phenylbutanamide was confirmed and a route specific marker was proposed. This is the first study that demonstrates that non-target screening of wastewater can identify intermediates, impurities and by products of the synthesis routes used in illegal manufacturing of amphetamine. The profiles of chemicals thus obtained can be used in tracking productions sites within the corresponding sewer catchment. Copyright © 2018 Elsevier B.V. All rights reserved.
[Coffee as hepatoprotective factor].
Szántová, Mária; Ďurkovičová, Zuzana
The mind about the coffee did change upon the recent studies and metaanalysis of the last years. Consensual protective effect of coffee on the progression of chronic liver diseases (NASH, viral hepatitis, liver cirrhosis, hepatocelullar carcinoma) was detected in experimental, clinical and large population studies together with decrease of mortality. Antioxidant, antifibrotic, insulinsensitizing and anticarcinogenic effect of coffee were detected. Modulation of genetic expression of key enzymes of fatty acid synthesis, modulation of mRNA included in autophagia, reduction of stress of endoplasmatic reticulum together with decrease of proinflammatory cytokines and decrease of fibrogenesis are main mechanisms. Chlorogenic acids, diterpens (cafestol, kahweol), caffein, polyfenols and melanoidins are key protective components of coffee. Inverse dose-dependent correlation of coffee consumption with liver diseases was found in clinical and population studies. Coffee is non-pharmacological tool of primary and secondary prevention of chronic liver diseases. Review of published data together with supposed mechanisms of hepatoprotection are given.Key words: coffee - hepatoprotective effect - metaanalysis.
Wang, Yijin; Wang, Wenshi; Xu, Lei; Zhou, Xinying; Shokrollahi, Ehsan; Felczak, Krzysztof; van der Laan, Luc J. W.; Pankiewicz, Krzysztof W.; Sprengers, Dave; Raat, Nicolaas J. H.; Metselaar, Herold J.; Peppelenbosch, Maikel P.
2016-01-01
Viruses are solely dependent on host cells to propagate; therefore, understanding virus-host interaction is important for antiviral drug development. Since de novo nucleotide biosynthesis is essentially required for both host cell metabolism and viral replication, specific catalytic enzymes of these pathways have been explored as potential antiviral targets. In this study, we investigated the role of different enzymatic cascades of nucleotide biosynthesis in hepatitis E virus (HEV) replication. By profiling various pharmacological inhibitors of nucleotide biosynthesis, we found that targeting the early steps of the purine biosynthesis pathway led to the enhancement of HEV replication, whereas targeting the later step resulted in potent antiviral activity via the depletion of purine nucleotide. Furthermore, the inhibition of the pyrimidine pathway resulted in potent anti-HEV activity. Interestingly, all of these inhibitors with anti-HEV activity concurrently triggered the induction of antiviral interferon-stimulated genes (ISGs). Although ISGs are commonly induced by interferons via the JAK-STAT pathway, their induction by nucleotide synthesis inhibitors is completely independent of this classical mechanism. In conclusion, this study revealed an unconventional novel mechanism of cross talk between nucleotide biosynthesis pathways and cellular antiviral immunity in constraining HEV infection. Targeting particular enzymes in nucleotide biosynthesis represents a viable option for antiviral drug development against HEV. HEV is the most common cause of acute viral hepatitis worldwide and is also associated with chronic hepatitis, especially in immunocompromised patients. Although often an acute and self-limiting infection in the general population, HEV can cause severe morbidity and mortality in certain patients, a problem compounded by the lack of FDA-approved anti-HEV medication available. In this study, we have investigated the role of the nucleotide synthesis pathway in HEV infection and its potential for antiviral drug development. We show that targeting the later but not the early steps of the purine synthesis pathway exerts strong anti-HEV activity. In particular, IMP dehydrogenase (IMPDH) is the most important anti-HEV target of this cascade. Importantly, the clinically used IMPDH inhibitors, including mycophenolic acid and ribavirin, have potent anti-HEV activity. Furthermore, targeting the pyrimidine synthesis pathway also exerts potent antiviral activity against HEV. Interestingly, antiviral effects of nucleotide synthesis pathway inhibitors appear to depend on the medication-induced transcription of antiviral interferon-stimulated genes. Thus, this study reveals an unconventional novel mechanism as to how nucleotide synthesis pathway inhibitors can counteract HEV replication. PMID:26926637
ERIC Educational Resources Information Center
Population Bulletin of the United Nations, 1993
1993-01-01
A review of six expert group meetings was organized to discuss various population and development issues and present individual group reports. The review begins with a synthesis of the meetings and gives a brief description of the organizational aspects of the meetings, a summary of recommendations, and an overview of important issues examined at…
NASA Astrophysics Data System (ADS)
Gomes, J. M.; Papaderos, P.
2017-07-01
The goal of population spectral synthesis (pss; also referred to as inverse, semi-empirical evolutionary- or fossil record approach) is to decipher from the spectrum of a galaxy the mass, age and metallicity of its constituent stellar populations. This technique, which is the reverse of but complementary to evolutionary synthesis, has been established as fundamental tool in extragalactic research. It has been extensively applied to large spectroscopic data sets, notably the SDSS, leading to important insights into the galaxy assembly history. However, despite significant improvements over the past decade, all current pss codes suffer from two major deficiencies that inhibit us from gaining sharp insights into the star-formation history (SFH) of galaxies and potentially introduce substantial biases in studies of their physical properties (e.g., stellar mass, mass-weighted stellar age and specific star formation rate). These are I) the neglect of nebular emission in spectral fits, consequently; II) the lack of a mechanism that ensures consistency between the best-fitting SFH and the observed nebular emission characteristics of a star-forming (SF) galaxy (e.g., hydrogen Balmer-line luminosities and equivalent widths-EWs, shape of the continuum in the region around the Balmer and Paschen jump). In this article, we present fado (Fitting Analysis using Differential evolution Optimization) - a conceptually novel, publicly available pss tool with the distinctive capability of permitting identification of the SFH that reproduces the observed nebular characteristics of a SF galaxy. This so-far unique self-consistency concept allows us to significantly alleviate degeneracies in current spectral synthesis, thereby opening a new avenue to the exploration of the assembly history of galaxies. The innovative character of fado is further augmented by its mathematical foundation: fado is the first pss code employing genetic differential evolution optimization. This, in conjunction with various other currently unique elements in its mathematical concept and numerical realization (e.g., mid-analysis optimization of the spectral library using artificial intelligence, test for convergence through a procedure inspired by Markov chain Monte Carlo techniques, quasi-parallelization embedded within a modular architecture) results in key improvements with respect to computational efficiency and uniqueness of the best-fitting SFHs. Furthermore, fado incorporates within a single code the entire chain of pre-processing, modeling, post-processing, storage and graphical representation of the relevant output from pss, including emission-line measurements and estimates of uncertainties for all primary and secondary products from spectral synthesis (e.g., mass contributions of individual stellar populations, mass- and luminosity-weighted stellar ages and metallicities). This integrated concept greatly simplifies and accelerates a lengthy sequence of individual time-consuming steps that are generally involved in pss modeling, further enhancing the overall efficiency of the code and inviting to its automated application to large spectroscopic data sets. The distribution package of the FADO v.1 tool contains the binary and its auxiliary files. FADO v.1 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/603/A63
Subdwarf B Stars: Tracers Of Binary Evolution
NASA Astrophysics Data System (ADS)
Morales-Rueda, L.; Maxted, P. F. L.; Marsh, T. R.
2007-08-01
Subdwarf B stars are a superb stellar population to study binary evolution. In 2001, Maxted et al. (MNRAS, 326, 1391) found that 21 out of the 36 subdwarf B stars they studied were in short period binaries. These observations inspired new theoretical work that suggests that up to 90 per cent of subdwarf B stars are in binary systems with the remaining apparently single stars being the product of merging pairs. This high binary fraction added to the fact that they are detached binaries that have not changed significantly since they came out of the common envelope, make subdwarf B stars a perfect population to study binary evolution. By comparing the observed orbital period distribution of subdwarf B stars with that obtained from population synthesis calculations we can determine fundamental parameters of binary evolution such as the common envelope ejection efficiency. Here we give an overview of the fraction of short period binaries found from different surveys as well as the most up to date orbital period distribution determined observationally. We also present results from a recent search for subdwarf B stars in long period binaries.
Sisnowski, Jana; Merlin, Tracy
2017-01-01
Background This systematic review (PROSPERO: CRD42015025276) employs a realist approach to investigate the effect of “real-world” policies targeting different aspects of the food environment that shape individual and collective nutrition. Objectives We were interested in assessing intermediate outcomes along the assumed causal pathway to “policy success”, in addition to the final outcome of changed consumption patterns. Data sources We performed a search of 16 databases through October 2015, with no initial restriction by language. Study eligibility criteria We included all publications that reported the effect of statutory provisions aimed at reducing the consumption of energy-dense foods and beverages in the general population. We allowed all methodological approaches that contained some measure of comparison, including studies of implementation progress. Study appraisal and synthesis methods We reviewed included studies using the appraisal tools for pre-post and observational studies developed by the National Heart, Lung, and Blood Institute. Given the considerable heterogeneity in interventions assessed, study designs employed, and outcome measures reported, we opted for a narrative synthesis of results. Results and implications Results drawn from 36 peer-reviewed articles and grey literature reports demonstrated that isolated regulatory interventions can improve intermediate outcomes, but fail to affect consumption at clinically significant levels. The included literature covered six different types of interventions, with 19 studies reporting on calorie posting on chain restaurant menus. The large majority of the identified interventions were conducted in the US. Early results from recent taxation measures were published after the review cut-off date but these suggested more favorable effects on consumption levels. Nevertheless, the evidence assessed in this review suggests that current policies are generally falling short of anticipated health impacts. PMID:28783757
Eakin, Elizabeth G; Bull, Sheana S; Glasgow, Russell E; Mason, Mondi
2002-01-01
There has been increased recognition of the importance of developing diabetes self-management education (DSME) interventions that are effective with under-served and minority populations. Despite several recent studies in this area, there is to our knowledge no systematic review or synthesis of what has been learned from this research. An electronic literature search identified five formative evaluations and ten controlled DSME intervention trials focused on under-served (low-income, minority or aged) populations. The RE-AIM (Reach, Efficacy, Adoption, Implementation, Maintenance) evaluation framework was used to evaluate the controlled studies on the dimensions of reach, efficacy, adoption, implementation, and maintenance. Fifty percent of the studies identified reported on the percentage of patients who participated, and the percentages were highly variable. The methodological quality of the articles was generally good and the short-term results were encouraging, especially on behavioral outcomes. Data on adoption (representativeness of settings and clinicians who participate) and implementation were almost never reported. Studies of modalities in addition to group meetings are needed to increase the reach of DSME with under-served populations. The promising formative evaluation work that has been conducted needs to be extended for more systematic study of the process of intervention implementation and adaptation with special populations. Studies that explicitly address the community context and that address multiple issues related to public health impact of DSME interventions are recommended to enhance long-term results. Copyright 2002 John Wiley & Sons, Ltd.
Understanding diversity–stability relationships: towards a unified model of portfolio effects
Thibaut, Loïc M; Connolly, Sean R; He, Fangliang
2013-01-01
A major ecosystem effect of biodiversity is to stabilise assemblages that perform particular functions. However, diversity–stability relationships (DSRs) are analysed using a variety of different population and community properties, most of which are adopted from theory that makes several restrictive assumptions that are unlikely to be reflected in nature. Here, we construct a simple synthesis and generalisation of previous theory for the DSR. We show that community stability is a product of two quantities: the synchrony of population fluctuations, and an average species-level population stability that is weighted by relative abundance. Weighted average population stability can be decomposed to consider effects of the mean-variance scaling of abundance, changes in mean abundance with diversity and differences in species' mean abundance in monoculture. Our framework makes explicit how unevenness in the abundances of species in real communities influences the DSR, which occurs both through effects on community synchrony, and effects on weighted average population variability. This theory provides a more robust framework for analysing the results of empirical studies of the DSR, and facilitates the integration of findings from real and model communities. PMID:23095077
Jakovljevic, Ksenija; Malisic, Emina; Cavic, Milena; Radulovic, Sinisa; Jankovic, Radmila
2012-07-01
Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme regulating the intracellular folate metabolism which plays an important role in carcinogenesis through DNA methylation and nucleotide synthesis. The common MTHFR single nucleotide polymorphism C677T has been reported to be associated with reduced enzymatic activity. In order to investigate the influence of this polymorphism on the risk of chronic myeloid leukemia (CML), we performed a case-control study in a Serbian population of 52 patients with CML and 53 healthy control subjects. MTHFR C677T polymorphism genotyping was assessed using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The results demonstrated no statistical difference in MTHFR 677 frequency distribution between patient and control groups. Our findings suggest that MTHFR 677 gene variants have no significant influence on the susceptibility to CML in a Serbian population.
Mels, Catharina M C; Huisman, Hugo W; Smith, Wayne; Schutte, Rudolph; Schwedhelm, Edzard; Atzler, Dorothee; Böger, Rainer H; Ware, Lisa J; Schutte, Aletta E
2016-02-01
Inadequate substrate availability and increased nitric oxide synthase inhibitor levels attenuate nitric oxide (NO) synthesis, whereas increased vascular oxidative stress may lead to inactivation of NO. We compared markers of NO synthesis capacity and oxidative stress in a bi-ethnic male population. Inter-relationships of ambulatory blood pressure and urinary albumin-to-creatinine ratio with NO synthesis capacity and oxidative stress markers were investigated. NO synthesis capacity markers (L-arginine, asymmetric dimethylarginine (ADMA), and symmetric dimethylarginine (SDMA)) and oxidative stress markers (serum peroxides, total glutathione, glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD), and catalase) were measured. Black men displayed higher blood pressure and albumin-to-creatinine ratio (all p < 0.001), while NO synthesis capacity was more favorable (higher L-arginine and lower ADMA (p ≤ 0.003)). Antioxidant enzyme activities were similar except for the redox status markers (GR activity and GR/GPx ratio), which were upregulated in black men (p < 0.001). In black men, ADMA was inversely related to GPx activity (R (2) = 0.15; β = -0.20; p = 0.050) and GPx/SOD ratio (R (2) = 0.24; β = -0.37; p < 0.001), but none of these markers related to blood pressure or albumin-to-creatinine ratio. In white men, albumin-to-creatinine ratio was positively associated with ADMA (R (2) = 0.18; β = 0.39; p < 0.001) while ADMA was inversely related to GR activity (R (2) = 0.26; β = -0.29; p = 0.002) and GR/GPx ratio (R (2) = 0.25; β = -0.28; p = 0.003). Black men with elevated blood pressure and albumin-to-creatinine ratio displayed a favorable NO synthesis capacity. This may be counteracted by increased inactivation of NO, although it was not linked to vascular or renal phenotypes. In white men, reduced NO synthesis capacity may lower NO bio-availability, thereby influencing the albumin-to-creatinine ratio.
The health and socioeconomic impacts of major multi-sport events: systematic review (1978-2008)
Thomas, Sian; Thomson, Hilary; Scott, John; Hamilton, Val; Hanlon, Phil; Morrison, David S; Bond, Lyndal
2010-01-01
Objective To assess the effects of major multi-sport events on health and socioeconomic determinants of health in the population of the city hosting the event. Design Systematic review. Data sources We searched the following sources without language restrictions for papers published between 1978 and 2008: Applied Social Science Index and Abstracts (ASSIA), British Humanities Index (BHI), Cochrane database of systematic reviews, Econlit database, Embase, Education Resources Information Center (ERIC) database, Health Management Information Consortium (HMIC) database, International Bibliography of the Social Sciences (IBSS), Medline, PreMedline, PsycINFO, Sociological Abstracts, Sportdiscus, Web of Knowledge, Worldwide Political Science Abstracts, and the grey literature. Review methods Studies of any design that assessed the health and socioeconomic impacts of major multi-sport events on the host population were included. We excluded studies that used exclusively estimated data rather than actual data, that investigated host population support for an event or media portrayals of host cities, or that described new physical infrastructure. Studies were selected and critically appraised by two independent reviewers. Results Fifty four studies were included. Study quality was poor, with 69% of studies using a repeat cross-sectional design and 85% of quantitative studies assessed as being below 2+ on the Health Development Agency appraisal scale, often because of a lack of comparison group. Five studies, each with a high risk of bias, reported health related outcomes, which were suicide, paediatric health service demand, presentations for asthma in children (two studies), and problems related to illicit drug use. Overall, the data did not indicate clear negative or positive health impacts of major multi-sport events on host populations. The most frequently reported outcomes were economic outcomes (18 studies). The outcomes used were similar enough to allow us to perform a narrative synthesis, but the overall impact of major multi-sport events on economic growth and employment was unclear. Two thirds of the economic studies reported increased economic growth or employment immediately after the event, but all these studies used some estimated data in their models, failed to account for opportunity costs, or examined only short term effects. Outcomes for transport were also similar enough to allow synthesis of six of the eight studies, which showed that event related interventions—including restricted car use and public transport promotion—were associated with significant short term reductions in traffic volume, congestion, or pollution in four out of five cities. Conclusions The available evidence is not sufficient to confirm or refute expectations about the health or socioeconomic benefits for the host population of previous major multi-sport events. Future events such as the 2012 Olympic Games and Paralympic Games, or the 2014 Commonwealth Games, cannot be expected to automatically provide benefits. Until decision makers include robust, long term evaluations as part of their design and implementation of events, it is unclear how the costs of major multi-sport events can be justified in terms of benefits to the host population. PMID:20488915
The health and socioeconomic impacts of major multi-sport events: systematic review (1978-2008).
McCartney, Gerry; Thomas, Sian; Thomson, Hilary; Scott, John; Hamilton, Val; Hanlon, Phil; Morrison, David S; Bond, Lyndal
2010-05-20
To assess the effects of major multi-sport events on health and socioeconomic determinants of health in the population of the city hosting the event. Systematic review. We searched the following sources without language restrictions for papers published between 1978 and 2008: Applied Social Science Index and Abstracts (ASSIA), British Humanities Index (BHI), Cochrane database of systematic reviews, Econlit database, Embase, Education Resources Information Center (ERIC) database, Health Management Information Consortium (HMIC) database, International Bibliography of the Social Sciences (IBSS), Medline, PreMedline, PsycINFO, Sociological Abstracts, Sportdiscus, Web of Knowledge, Worldwide Political Science Abstracts, and the grey literature. Review methods Studies of any design that assessed the health and socioeconomic impacts of major multi-sport events on the host population were included. We excluded studies that used exclusively estimated data rather than actual data, that investigated host population support for an event or media portrayals of host cities, or that described new physical infrastructure. Studies were selected and critically appraised by two independent reviewers. Fifty four studies were included. Study quality was poor, with 69% of studies using a repeat cross-sectional design and 85% of quantitative studies assessed as being below 2+ on the Health Development Agency appraisal scale, often because of a lack of comparison group. Five studies, each with a high risk of bias, reported health related outcomes, which were suicide, paediatric health service demand, presentations for asthma in children (two studies), and problems related to illicit drug use. Overall, the data did not indicate clear negative or positive health impacts of major multi-sport events on host populations. The most frequently reported outcomes were economic outcomes (18 studies). The outcomes used were similar enough to allow us to perform a narrative synthesis, but the overall impact of major multi-sport events on economic growth and employment was unclear. Two thirds of the economic studies reported increased economic growth or employment immediately after the event, but all these studies used some estimated data in their models, failed to account for opportunity costs, or examined only short term effects. Outcomes for transport were also similar enough to allow synthesis of six of the eight studies, which showed that event related interventions--including restricted car use and public transport promotion--were associated with significant short term reductions in traffic volume, congestion, or pollution in four out of five cities. The available evidence is not sufficient to confirm or refute expectations about the health or socioeconomic benefits for the host population of previous major multi-sport events. Future events such as the 2012 Olympic Games and Paralympic Games, or the 2014 Commonwealth Games, cannot be expected to automatically provide benefits. Until decision makers include robust, long term evaluations as part of their design and implementation of events, it is unclear how the costs of major multi-sport events can be justified in terms of benefits to the host population.
Bader, Pearl; Boisclair, David; Ferrence, Roberta
2011-01-01
Tobacco taxation is an essential component of a comprehensive tobacco control strategy. However, to fully realize the benefits it is vital to understand the impact of increased taxes among high-risk subpopulations. Are they influenced to the same extent as the general population? Do they need additional measures to influence smoking behavior? The objectives of this study were to synthesize the evidence regarding differential effects of taxation and price on smoking in: youth, young adults, persons of low socio-economic status, with dual diagnoses, heavy/long-term smokers, and Aboriginal people. Using a better practices approach, a knowledge synthesis was conducted using a systematic review of the literature and an expert advisory panel. Experts were involved in developing the study plan, discussing findings, developing policy recommendations, and identifying priorities for future research. Most studies found that raising cigarette prices through increased taxes is a highly effective measure for reducing smoking among youth, young adults, and persons of low socioeconomic status. However, there is a striking lack of evidence about the impact of increasing cigarette prices on smoking behavior in heavy/long-term smokers, persons with a dual diagnosis and Aboriginals. Given their high prevalence of smoking, urgent attention is needed to develop effective policies for the six subpopulations reviewed. These findings will be of value to policy-makers and researchers in their efforts to improve the effectiveness of tobacco control measures, especially with subpopulations at most risk. Although specific studies are needed, tobacco taxation is a key policy measure for driving success. PMID:22163198
A Synthesis of the Effects of Pesticides on Microbial Persistence in Aquatic Ecosystems
Staley, Zachery R.; Harwood, Valerie J.; Rohr, Jason R.
2016-01-01
Pesticides are a pervasive presence in aquatic ecosystems throughout the world. While pesticides are intended to control fungi, insects, and other pests, their mechanisms of action are often not specific enough to prevent unintended effects, such as on non-target microbial populations. Microorganisms, including algae and cyanobacteria, protozoa, aquatic fungi, and bacteria, form the basis of many food webs and are responsible for crucial aspects of biogeochemical cycling; therefore, the potential for pesticides to alter microbial community structures must be understood to preserve ecosystem services. This review examines studies that focused on direct population-level effects and indirect community-level effects of pesticides on microorganisms. Generally, insecticides, herbicides, and fungicides were found to have adverse direct effects on algal and fungal species. Insecticides and fungicides also had deleterious direct effects in the majority of studies examining protozoa species, although herbicides were found to have inconsistent direct effects on protozoans. Our synthesis revealed mixed or no direct effects on bacterial species among all pesticide categories, with results highly dependent on the target species, chemical, and concentration used in the study. Examination of community-level, indirect effects revealed that all pesticide categories had a tendency to reduce higher trophic levels, thereby diminishing top-down pressures and favoring lower trophic levels. Often, indirect effects exerted greater influence than direct effects. However, few studies have been conducted to specifically address community-level effects of pesticides on microorganisms and further research is necessary to better understand and predict the net effects of pesticides on ecosystem health. PMID:26565685
Bader, Pearl; Boisclair, David; Ferrence, Roberta
2011-11-01
Tobacco taxation is an essential component of a comprehensive tobacco control strategy. However, to fully realize the benefits it is vital to understand the impact of increased taxes among high-risk subpopulations. Are they influenced to the same extent as the general population? Do they need additional measures to influence smoking behavior? The objectives of this study were to synthesize the evidence regarding differential effects of taxation and price on smoking in: youth, young adults, persons of low socio-economic status, with dual diagnoses, heavy/long-term smokers, and Aboriginal people. Using a better practices approach, a knowledge synthesis was conducted using a systematic review of the literature and an expert advisory panel. Experts were involved in developing the study plan, discussing findings, developing policy recommendations, and identifying priorities for future research. Most studies found that raising cigarette prices through increased taxes is a highly effective measure for reducing smoking among youth, young adults, and persons of low socioeconomic status. However, there is a striking lack of evidence about the impact of increasing cigarette prices on smoking behavior in heavy/long-term smokers, persons with a dual diagnosis and Aboriginals. Given their high prevalence of smoking, urgent attention is needed to develop effective policies for the six subpopulations reviewed. These findings will be of value to policy-makers and researchers in their efforts to improve the effectiveness of tobacco control measures, especially with subpopulations at most risk. Although specific studies are needed, tobacco taxation is a key policy measure for driving success.
Safer stops for vulnerable customers
DOT National Transportation Integrated Search
2003-03-01
This synthesis report presents a brief synopsis of the current literature and technologies being used in the development of safer and more secure bus stops. While the focus is more specifically with regard to vulnerable populations - women, children,...
Pulsar Polar Cap and Slot Gap Models: Confronting Fermi Data
NASA Technical Reports Server (NTRS)
Harding, Alice K.
2012-01-01
Rotation-powered pulsars are excellent laboratories for studying particle acceleration as well as fundamental physics of strong gravity, strong magnetic fields and relativity. I will review acceleration and gamma-ray emission from the pulsar polar cap and slot gap. Predictions of these models can be tested with the data set on pulsars collected by the Large Area Telescope on the Fermi Gamma-Ray Telescope over the last four years, using both detailed light curve fitting and population synthesis.
Younger, Jane L; Emmerson, Louise M; Miller, Karen J
2016-02-01
The Southern Ocean ecosystem is undergoing rapid physical and biological changes that are likely to have profound implications for higher-order predators. Here, we compare the long-term, historical responses of Southern Ocean predators to climate change. We examine palaeoecological evidence for changes in the abundance and distribution of seabirds and marine mammals, and place these into context with palaeoclimate records in order to identify key environmental drivers associated with population changes. Our synthesis revealed two key factors underlying Southern Ocean predator population changes; (i) the availability of ice-free ground for breeding and (ii) access to productive foraging grounds. The processes of glaciation and sea ice fluctuation were key; the distributions and abundances of elephant seals, snow petrels, gentoo, chinstrap and Adélie penguins all responded strongly to the emergence of new breeding habitat coincident with deglaciation and reductions in sea ice. Access to productive foraging grounds was another limiting factor, with snow petrels, king and emperor penguins all affected by reduced prey availability in the past. Several species were isolated in glacial refugia and there is evidence that refuge populations were supported by polynyas. While the underlying drivers of population change were similar across most Southern Ocean predators, the individual responses of species to environmental change varied because of species specific factors such as dispersal ability and environmental sensitivity. Such interspecific differences are likely to affect the future climate change responses of Southern Ocean marine predators and should be considered in conservation plans. Comparative palaeoecological studies are a valuable source of long-term data on species' responses to environmental change that can provide important insights into future climate change responses. This synthesis highlights the importance of protecting productive foraging grounds proximate to breeding locations, as well as the potential role of polynyas as future Southern Ocean refugia. © 2015 John Wiley & Sons Ltd.
Overproduction of laccase and pectinase by microbial associations in solid substrate fermentation.
Stoilova, Ivanka; Krastanov, Albert
2008-04-01
The growth and the enzymatic production of two microbial fungal associations were studied: Aspergillus niger and Fusarium moniliforme and Trametes versicolor and Aspergillus niger. The synergistic interrelations between the species of the first mixed culture increased the biosynthesis of alpha-amylase and pectinase. T. versicolor and A. niger proved to be compatible partners in the overproduction of the enzyme laccase, whose synthesis surpassed 8.4 times the enzymatic level in the monoculture, with both of the mixed microbial populations cocultivation facilitating the amplified synthesis of enzymes rather than their growth acceleration. A further proof of the presence of synergism established by the cultures was the enzyme volumetric productivities in both of the mixed microbial cultures, which increased parallel to the rise in the combined biomass synthesis. The competent selection of compatible partners can adjust the desired enzymatic levels and compositions in mixed fungal systems aimed at a number of specified designations. Thus, a very high level of laccase production (97,600 IU/g dry weight) was achieved. The chosen fungal strains produce a variety of different enzymes, but first microbial association produces mainly amylase and pectinase, necessary for their growth, and second association produces mainly laccase and pectinase.
DNA Dispose, but Subjects Decide. Learning and the Extended Synthesis.
Lindholm, Markus
Adaptation by means of natural selection depends on the ability of populations to maintain variation in heritable traits. According to the Modern Synthesis this variation is sustained by mutations and genetic drift. Epigenetics, evodevo, niche construction and cultural factors have more recently been shown to contribute to heritable variation, however, leading an increasing number of biologists to call for an extended view of speciation and evolution. An additional common feature across the animal kingdom is learning, defined as the ability to change behavior according to novel experiences or skills. Learning constitutes an additional source for phenotypic variation, and change in behavior may induce long lasting shifts in fitness, and hence favor evolutionary novelties. Based on published studies, I demonstrate how learning about food, mate choice and habitats has contributed substantially to speciation in the canonical story of Darwin's finches on the Galapagos Islands. Learning cannot be reduced to genetics, because it demands decisions, which requires a subject. Evolutionary novelties may hence emerge both from shifts in allelic frequencies and from shifts in learned, subject driven behavior. The existence of two principally different sources of variation also prevents the Modern Synthesis from self-referring explanations.
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
Doble, Brett; Tan, Marcus; Harris, Anthony; Lorgelly, Paula
2015-02-01
The successful use of a targeted therapy is intrinsically linked to the ability of a companion diagnostic to correctly identify patients most likely to benefit from treatment. The aim of this study was to review the characteristics of companion diagnostics that are of importance for inclusion in an economic evaluation. Approaches for including these characteristics in model-based economic evaluations are compared with the intent to describe best practice methods. Five databases and government agency websites were searched to identify model-based economic evaluations comparing a companion diagnostic and subsequent treatment strategy to another alternative treatment strategy with model parameters for the sensitivity and specificity of the companion diagnostic (primary synthesis). Economic evaluations that limited model parameters for the companion diagnostic to only its cost were also identified (secondary synthesis). Quality was assessed using the Quality of Health Economic Studies instrument. 30 studies were included in the review (primary synthesis n = 12; secondary synthesis n = 18). Incremental cost-effectiveness ratios may be lower when the only parameter for the companion diagnostic included in a model is the cost of testing. Incorporating the test's accuracy in addition to its cost may be a more appropriate methodological approach. Altering the prevalence of the genetic biomarker, specific population tested, type of test, test accuracy and timing/sequence of multiple tests can all impact overall model results. The impact of altering a test's threshold for positivity is unknown as it was not addressed in any of the included studies. Additional quality criteria as outlined in our methodological checklist should be considered due to the shortcomings of standard quality assessment tools in differentiating studies that incorporate important test-related characteristics and those that do not. There is a need to refine methods for incorporating the characteristics of companion diagnostics into model-based economic evaluations to ensure consistent and transparent reimbursement decisions are made.
NASA Astrophysics Data System (ADS)
Lee, Go-Woon; Ambade, Swapnil B.; Cho, Young-Jin; Mane, Rajaram S.; Shashikala, V.; Yadav, Jyotiprakash; Gaikwad, Rajendra S.; Lee, Soo-Hyoung; Jung, Kwang-Deog; Han, Sung-Hwan; Joo, Oh-Shim
2010-03-01
We report for the first time, using a simple and environmentally benign chemical method, the low temperature synthesis of densely populated upright-standing rutile TiO2 nanoplate films onto a glass substrate from a mixture of titanium trichloride, hydrogen peroxide and thiourea in triply distilled water. The rutile TiO2 nanoplate films (the phase is confirmed from x-ray diffraction analysis, selected area electron diffraction, energy-dispersive x-ray analysis, and Raman shift) are 20-35 nm wide and 100-120 nm long. The chemical reaction kinetics for the growth of these upright-standing TiO2 nanoplate films is also interpreted. Films of TiO2 nanoplates are optically transparent in the visible region with a sharp absorption edge close to 350 nm, confirming an indirect band gap energy of 3.12 eV. The Brunauer-Emmet-Teller surface area, Barret-Joyner-Halenda pore volume and pore diameter, obtained from N2 physisorption studies, are 82 m2 g - 1, 0.0964 cm3 g - 1 and 3.5 nm, respectively, confirming the mesoporosity of scratched rutile TiO2 nanoplate powder that would be ideal for the direct fabrication of nanoscaled devices including upcoming dye-sensitized solar cells and gas sensors.
Tataw, David Besong; Ekúndayò, Olúgbémiga T
2017-01-01
This article reports on the use of sequential and integrated mixed-methods approach in a focused population and small-area analysis. The study framework integrates focus groups, survey research, and community engagement strategies in a search for evidence related to prostate cancer screening services utilization as a component of cancer prevention planning in a marginalized African American community in the United States. Research and data analysis methods are synthesized by aggregation, configuration, and interpretive analysis. The results of synthesis show that qualitative and quantitative data validate and complement each other in advancing our knowledge of population characteristics, variable associations, the complex context in which variables exist, and the best options for prevention and service planning. Synthesis of findings and interpretive analysis provided two important explanations which seemed inexplicable in regression outputs: (a) Focus group data on the limitations of the church as an educational source explain the negative association between preferred educational channels and screening behavior found in quantitative analysis. (b) Focus group data on unwelcoming provider environments explain the inconsistent relationship between knowledge of local sites and screening services utilization found in quantitative analysis. The findings suggest that planners, evaluators, and scientists should grow their planning and evaluation evidence from the community they serve.
Roland, Carl L; Lake, Joanita; Oderda, Gary M
2016-12-01
We conducted a systematic review to evaluate worldwide human English published literature from 2009 to 2014 on prevalence of opioid misuse/abuse in retrospective databases where International Classification of Diseases (ICD) codes were used. Inclusion criteria for the studies were use of a retrospective database, measured abuse, dependence, and/or poisoning using ICD codes, stated prevalence or it could be derived, and documented time frame. A meta-analysis was not performed. A qualitative narrative synthesis was used, and 16 studies were included for data abstraction. ICD code use varies; 10 studies used ICD codes that encompassed all three terms: abuse, dependence, or poisoning. Eight studies limited determination of misuse/abuse to an opioid user population. Abuse prevalence among opioid users in commercial databases using all three terms of ICD codes varied depending on the opioid; 21 per 1000 persons (reformulated extended-release oxymorphone; 2011-2012) to 113 per 1000 persons (immediate-release opioids; 2010-2011). Abuse prevalence in general populations using all three ICD code terms ranged from 1.15 per 1000 persons (commercial; 6 months 2010) to 8.7 per 1000 persons (Medicaid; 2002-2003). Prevalence increased over time. When similar ICD codes are used, the highest prevalence is in US government-insured populations. Limiting population to continuous opioid users increases prevalence. Prevalence varies depending on ICD codes used, population, time frame, and years studied. Researchers using ICD codes to determine opioid abuse prevalence need to be aware of cautions and limitations.
Bauermeister, José A; Connochie, Daniel; Eaton, Lisa; Demers, Michele; Stephenson, Rob
Young men who have sex with men (YMSM), particularly YMSM who are racial/ethnic minorities, are disproportionately affected by the human immunodeficiency virus (HIV) epidemic in the United States. These HIV disparities have been linked to demographic, social, and physical geospatial characteristics. The objective of this scoping review was to summarize the existing evidence from multilevel studies examining how geospatial characteristics are associated with HIV prevention and care outcomes among YMSM populations. Our literature search uncovered 126 peer-reviewed articles, of which 17 were eligible for inclusion based on our review criteria. Nine studies examined geospatial characteristics as predictors of HIV prevention outcomes. Nine of the 17 studies reported HIV care outcomes. From the synthesis regarding the current state of research around geospatial correlates of behavioral and biological HIV risk, we propose strategies to move the field forward in order to inform the design of future multilevel research and intervention studies for this population.
A Minimalist NMR Approach for the Structural Revision of Mucoxin
Yan, Jun; Garzan, Atefeh; Narayan, Radha S.
2011-01-01
In an attempt to revise the structural assignment of mucoxin, and faced with 64 diastereomeric possibilities, we resorted to the synthesis of truncated structures that contained the core stereochemical sites. Twelve stereochemical analogues were synthesized, their 1H and 13C NMR spectra were analyzed and four recurring stereochemical trends were distilled from the data. Applying the observed trends to the diastereomeric population pared the possible choices for the correct structure of mucoxin from 64 to 4. Synthesis of these analogues led to the identification of the correct structure of mucoxin. PMID:21089037
Schwindt, Adam R; Winkelman, Dana L
2016-09-01
Urban freshwater streams in arid climates are wastewater effluent dominated ecosystems particularly impacted by bioactive chemicals including steroid estrogens that disrupt vertebrate reproduction. However, more understanding of the population and ecological consequences of exposure to wastewater effluent is needed. We used empirically derived vital rate estimates from a mesocosm study to develop a stochastic stage-structured population model and evaluated the effect of 17α-ethinylestradiol (EE2), the estrogen in human contraceptive pills, on fathead minnow Pimephales promelas stochastic population growth rate. Tested EE2 concentrations ranged from 3.2 to 10.9 ng L(-1) and produced stochastic population growth rates (λ S ) below 1 at the lowest concentration, indicating potential for population decline. Declines in λ S compared to controls were evident in treatments that were lethal to adult males despite statistically insignificant effects on egg production and juvenile recruitment. In fact, results indicated that λ S was most sensitive to the survival of juveniles and female egg production. More broadly, our results document that population model results may differ even when empirically derived estimates of vital rates are similar among experimental treatments, and demonstrate how population models integrate and project the effects of stressors throughout the life cycle. Thus, stochastic population models can more effectively evaluate the ecological consequences of experimentally derived vital rates.
On the Diversity in Mass and Orbital Radius of Giant Planets Formed via Disk Instability
NASA Astrophysics Data System (ADS)
Müller, Simon; Helled, Ravit; Mayer, Lucio
2018-02-01
We present a semi-analytical population synthesis model of protoplanetary clumps formed by disk instability at radial distances of 80–120 au. Various clump density profiles, initial mass functions, protoplanetary disk models, stellar masses, and gap opening criteria are considered. When we use more realistic gap opening criteria, we find that gaps open only rarely, which strongly affects clump survival rates and their physical properties (mass, radius, and radial distance). The inferred surviving population is then shifted toward less massive clumps at smaller radial distances. We also find that populations of surviving clumps are very sensitive to the model assumptions and used parameters. Depending on the chosen parameters, the protoplanets occupy a mass range between 0.01 and 16 M J and may either orbit close to the central star or as far out as 75 au, with a sweet spot at 10–30 au for the massive ones. However, in all of the cases we consider, we find that massive giant planets at very large radial distances are rare, in qualitative agreement with current direct imaging surveys. We conclude that caution should be taken in deriving population synthesis models as well as when comparing the models’ results with observations.
Evolutionary Theory under Fire.
ERIC Educational Resources Information Center
Lewin, Roger
1980-01-01
Summarizes events of a conference on evolutionary biology in Chicago entitled: "Macroevolution." Reviews the theory of modern synthesis, a term used to explain Darwinism in terms of population biology and genetics. Issues presented at the conference are discussed in detail. (CS)
Synthesis of Animal-Vehicle Collision Mitigation Measures.
DOT National Transportation Integrated Search
2007-08-01
In all western states, domestic animal and wildlife populations are increasing as well as the : vehicular traffic volumes. Consequently, increases in animal-vehicle collisions have been : reported by many states. The purpose of this report is to prov...
Meyer, J D F; Snook, M E; Houchins, K E; Rector, B G; Widstrom, N W; McMullen, M D
2007-06-01
Maysin is a naturally occurring C-glycosyl flavone found in maize (Zea mays L.) silk tissue that confers resistance to corn earworm (Helicoverpa zea, Boddie). Recently, two new maize populations were derived for high silk maysin. The two populations were named the exotic populations of maize (EPM) and the southern inbreds of maize (SIM). Quantitative trait locus (QTL) analysis was employed to determine which loci were responsible for elevated maysin levels in inbred lines derived from the EPM and SIM populations. The candidate genes consistent with QTL position included the p (pericarp color), c2 (colorless2), whp1 (white pollen1) and in1 (intensifier1) loci. The role of these loci in controlling high maysin levels in silks was tested by expression analysis and use of the loci as genetic markers onto the QTL populations. These studies support p, c2 and whp1, but not in1, as loci controlling maysin. Through this study, we determined that the p locus regulates whp1 transcription and that increased maysin in these inbred lines was primarily due to alleles at both structural and regulatory loci promoting increased flux through the flavone pathway by increasing chalcone synthase activity.
Bouzas-Ramos, Diego; García-Cortes, Marta; Sanz-Medel, Alfredo; Encinar, Jorge Ruiz; Costa-Fernández, José M
2017-10-13
Coupling of asymmetric flow field-flow fractionation (AF4) to an on-line elemental detection (inductively coupled plasma-mass spectrometry, ICP-MS) has been recently proposed as a powerful diagnostic tool for characterization of the bioconjugation of CdSe/ZnS core-shell Quantum Dots (QDs) to antibodies. Such approach has been used herein to demonstrate that cap exchange of the native hydrophobic shell of core/shell QDs with the bidentate dihydrolipoic acid ligands directly removes completely the eventual side nanoparticulated populations generated during simple one-pot synthesis, which can ruin the subsequent final bioapplication. The critical assessment of the chemical and physical purity of the surface-modified QDs achieved allows to explain the transmission electron microscopy findings obtained for the different nanoparticle surface modification assayed. Copyright © 2017 Elsevier B.V. All rights reserved.
Glutamic Acid as Enhancer of Protein Synthesis Kinetics in Hepatocytes from Old Rats.
Brodsky, V Y; Malchenko, L A; Butorina, N N; Lazarev Konchenko, D S; Zvezdina, N D; Dubovaya, T K
2017-08-01
Dense cultures of hepatocytes from old rats (~2 years old, body weight 530-610 g) are different from similar cultures of hepatocytes from young rats by the low amplitude of protein synthesis rhythm. Addition of glutamic acid (0.2, 0.4, or 0.6 mg/ml) into the culture medium with hepatocytes of old rats resulted in increase in the oscillation amplitudes of the protein synthesis rhythm to the level of young rats. A similar action of glutamic acid on the protein synthesis kinetics was observed in vivo after feeding old rats with glutamic acid. Inhibition of metabotropic receptors of glutamic acid with α-methyl-4-carboxyphenylglycine (0.01 mg/ml) abolished the effect of glutamic acid. The amplitude of oscillation of the protein synthesis rhythm in a cell population characterizes synchronization of individual oscillations caused by direct cell-cell communications. Hence, glutamic acid, acting as a receptor-dependent transmitter, enhanced direct cell-cell communications of hepatocytes that were decreased with aging. As differentiated from other known membrane signaling factors (gangliosides, norepinephrine, serotonin, dopamine), glutamic acid can penetrate into the brain and thus influence the communications and protein synthesis kinetics that are disturbed with aging not only in hepatocytes, but also in neurons.
Fernández, Catalina I; Montalva, Nicolás; Arias, Macarena; Hevia, Macarena; Moraga, Mauricio L; Flores, Sergio V
2016-01-01
Lactase persistence (LP) is a genetic trait that has been studied among different countries and ethnic groups. In Latin America, the frequencies of this trait have been shown to vary according to the degree of admixture of the populations. The objective of this study is to better understand the relationship between this genetic trait and dairy intake in a multiethnic context through a synthesis of studies conducted in four regions of Chile. Genotypes frequencies for the SNP LCT-13910C>T (rs4988235) and frequency of dairy consumption were obtained from four populations: Polynesians from Easter Island (Rapanui); Amerindians (Mapuche) and Mestizos from the Araucanía region; urban Mestizos from Santiago; and rural Mestizos from the Coquimbo region. Genetic differentiation and association between milk consumption and genotype frequencies were estimated. Genetic differentiation between Native and Mestizo populations was significant; the LP frequency in Mapuche and Rapanui was 10% and 25%, respectively, whereas among the Mestizos, LP frequency was near 40%. Dairy intake was below the nutritional recommendations for the four groups, and extremely below recommendations among the indigenous populations. Association between milk intake and LP was found in Santiago and Rapanui populations. Although the frequency of LP varies among the populations according to their degree of admixture, dairy consumption was very low across the populations. Given that the association between milk consumption and expected phenotype was found only in two of the populations analyzed, it seems that lactase non-persistence (LNP) is not the only cause for dairy avoidance. Thus, it is suggested that SES and cultural preferences are likely affecting dairy consumption. © 2015 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Ulrich, Clara; Hemmer-Hansen, Jakob; Boje, Jesper; Christensen, Asbjørn; Hüssy, Karin; Sun, Hailu; Clausen, Lotte Worsøe
2017-02-01
A multi-disciplinary study was conducted to clarify stock identity and connectivity patterns in the populations of European plaice (Pleuronectes platessa) in the Skagerrak-Kattegat transition area between the Eastern North Sea and the Baltic Sea. Five independent biological studies were carried out in parallel. Genetic markers suggested the existence of different genetic populations in the transition area. Growth backcalculation with otoliths resulted in significant although limited differences in growth rates between North Sea and Skagerrak, indicating weak differentiation or important mixing. Hydrogeographical drift modelling suggested that some North Sea juveniles could settle along the coast line of the Skagerrak and the Kattegat. Tagging data suggested that both juveniles and adult fish from the North Sea perform feeding migrations into Skagerrak in summer/autumn. Finally, survey data suggested that Skagerrak also belongs to the area distribution of North Sea plaice. The outcomes of the individual studies were then combined into an overall synthesis. The existence of some resident components was evidenced, but it was also demonstrated that North Sea plaice migrate for feeding into Skagerrak and might constitute a large share of the catches in this area. The mixing of different populations within a management area has implications for stock assessment and management. Choice must be made to either lump or split the populations, and the feasibility and constraints of both options are discussed. The outcomes of this work have directly influenced the management decisions in 2015.
Barbon, Carly E.A.; Steele, Catriona M.
2015-01-01
Objective To appraise the current videofluoroscopic evidence on the reduction of aspiration using thickened liquids in the head and neck cancer population. Data Sources Search terms relating to deglutition or dysphagia or swallow and neoplasms and oncology or head and neck cancer and viscosity or texture and apira or residu* were combined with honey or nectar, xerostomia, respiratory aspiration using Boolean operators. Review Methods A multi-engine literature search identified 337 non-duplicate articles of which 6 were judged to be relevant. These underwent detailed review for study quality and qualitative synthesis. Results The articles reviewed in detail predominantly described heterogeneous study samples with small sample sizes, making for difficult interpretation and generalization of results. Rates of aspiration were typically not reported by bolus consistency, despite the fact that a variety of stimulus consistencies was used during VFSS. Studies confirmed that aspiration is a major concern in the head and neck cancer population and reported a trend towards more frequent aspiration post-(chemo)radiotherapy. Conclusion Overall, the literature on thickened liquids as an intervention to eliminate aspiration in the head and neck cancer population is limited. Because aspiration is known to be prevalent in the head and neck cancer population and thickened liquids are known to eliminate aspiration in other populations, it is important to determine the effectiveness of thickened liquids for reducing aspiration in the head and neck cancer population. PMID:25358345
Birchley, Giles; Jones, Kerry; Huxtable, Richard; Dixon, Jeremy; Kitzinger, Jenny; Clare, Linda
2016-07-27
In most Anglophone nations, policy and law increasingly foster an autonomy-based model, raising issues for large numbers of people who fail to fit the paradigm, and indicating problems in translating practical and theoretical understandings of 'good death' to policy. Three exemplar populations are frail older people, people with dementia and people with severe traumatic brain injury. We hypothesise that these groups face some over-lapping challenges in securing good end-of-life care linked to their limited agency. To better understand these challenges, we conducted a scoping review and thematic synthesis. To capture a range of literature, we followed established scoping review methods. We then used thematic synthesis to describe the broad themes emerging from this literature. Initial searches generated 22,375 references, and screening yielded 49, highly heterogeneous, studies that met inclusion criteria, encompassing 12 countries and a variety of settings. The thematic synthesis identified three themes: the first concerned the processes of end-of-life decision-making, highlighting the ambiguity of the dominant shared decision-making process, wherein decisions are determined by families or doctors, sometimes explicitly marginalising the antecedent decisions of patients. Despite this marginalisation, however, the patient does play a role both as a social presence and as an active agent, by whose actions the decisions of those with authority are influenced. The second theme examined the tension between predominant notions of a good death as 'natural' and the drive to medicalise death through the lens of the experiences and actions of those faced with the actuality of death. The final theme considered the concept of antecedent end-of-life decision-making (in all its forms), its influence on policy and decision-making, and some caveats that arise from the studies. Together these three themes indicate a number of directions for future research, which are likely to be applicable to other conditions that result in reduced agency. Above all, this review emphasises the need for new concepts and fresh approaches to end of life decision-making that address the needs of the growing population of frail older people, people with dementia and those with severe traumatic brain injury.
Haldane's The causes of evolution and the Modern Synthesis in evolutionary biology.
Sarkar, Sahotra
2017-11-01
This paper argues that Haldane's The causes of evolution was the most important founding document in the emergence of the received view of evolutionary theory which is typically referred to as the Modern Synthesis. Whether or not this historical development is characterized as a synthesis (which remains controversial), this paper argues the most important component of the emergence of the received view consisted of showing how the formal rules of Mendelian inheritance are based on (or emerge from) the material basis of heredity established by classical genetics primarily through the experimental work on Drosophila genetics of the Morgan school in the 1910s and 1920s. This is one of the most important achievements of Haldane's book. Thus this paper rejects both (i) the view that the synthesis was a unification of biometry and Mendelism and (ii) the claim that it arose from work primarily done in the late 1930s and 1940s by naturalists rather than theoretical population and classical experimental geneticists.
Jeannotte, Guillaume; Lubell, William D
2004-11-10
For the first time, the influence of a fused Delta3-arylproline on peptide conformation has been studied by the synthesis and comparison of the conformations of peptides containing proline and pyrrolo-proline, 3 (PyPro). Pyrrolo-proline was demonstrated to be a conservative replacement for Pro in model beta-turns, 4 and 5, as shown by their similar DMSO titration curves, cis/trans-isomer populations, and NOESY spectral data. Pyrrolo-proline may thus be used for studying the structure activity relationships of Pro-containing peptides with minimal modification of secondary structures.
Torén, Kjell; Blanc, Paul D
2009-01-01
Background The aim of this paper is to highlight emerging data on occupational attributable risk in asthma. Despite well documented outbreaks of disease and the recognition of numerous specific causal agents, occupational exposures previously had been relegated a fairly minor role relative to other causes of adult onset asthma. In recent years there has been a growing recognition of the potential importance of asthma induced by work-related exposures Methods We searched Pub Med from June 1999 through December 2007. We identified six longitudinal general population-based studies; three case-control studies and eight cross-sectional analyses from seven general population-based samples. For an integrated analysis we added ten estimates prior to 1999 included in a previous review. Results The longitudinal studies indicate that 16.3% of all adult-onset asthma is caused by occupational exposures. In an overall synthesis of all included studies the overall median PAR value was 17.6%. Conclusion Clinicians should consider the occupational history when evaluating patients in working age who have asthma. At a societal level, these findings underscore the need for further preventive action to reduce the occupational exposures to asthma-causing agents. PMID:19178702
Coulon, J; Perello, M C; Lonvaud-Funel, A; de Revel, G; Renouf, V
2010-04-01
The presence of Brettanomyces bruxellensis is an important issue during winemaking because of its volatile phenols production capacities. The aim of this study is to provide information on the ability of residual B. bruxellensis populations to multiply and spoil finished wines during storage in bottles. Several finished wines were studied. Brettanomyces bruxellensis populations were monitored during two and a half months, and volatile phenols as well as chemical parameters regularly determined. Variable growth and volatile phenols synthesis capacities were evidenced, in particularly when cells are in a noncultivable state. In addition, the volatile phenol production was clearly shown to be a two-step procedure that could strongly be correlated to the physiological state of the yeast population. This study underlines the importance of minimizing B. bruxellensis populations at the end of wine ageing to reduce volatile phenols production risk once the wine in bottle. Moreover, the physiological state of the yeast seems to have an important impact on ethyl-phenols production, hence demonstrating the importance of taking into account this parameter when analysing wine spoilage risks. Little data exist about the survival of B. bruxellensis once the wine in bottle. This study provides information on the alteration risks encountered during wine storage in bottle and reveals the importance of carrying on further studies to increase the knowledge on B. bruxellensis physiology.
Dzomba, Armstrong; Govender, Kaymarlin; Mashamba-Thompson, Tivani P; Tanser, Frank
2018-02-27
In South Africa (home of the largest HIV epidemic globally), there are high levels of mobility. While studies produced in the recent past provide useful perspectives to the mobility-HIV risk linkage, systematic analyses are needed for in-depth understanding of the complex dynamics between mobility and HIV risk. We plan to undertake an evidence-based review of existing literature connecting mobility and increased risky sexual behavior as well as risk of HIV acquisition in South Africa. We will conduct a mixed-method systematic review of peer-reviewed studies published between 2000 and 2015. In particular, we will search for relevant South African studies from the following databases: MEDLINE, EMBASE, Web of Science, and J-STOR databases. Studies explicitly examining HIV and labor migration will be eligible for inclusion, while non-empirical work and other studies on key vulnerable populations such as commercial sex workers (CSW) and men who have sex with men (MSM) will be excluded. The proposed mixed-method systematic review will employ a three-phase sequential approach [i.e., (i) identifying relevant studies through data extraction (validated by use of Distiller-SR data management software), (ii) qualitative synthesis, and (iii) quantitative synthesis including meta-analysis data]. Recurrent ideas and conclusions from syntheses will be compiled into key themes and further processed into categories and sub-themes constituting the primary and secondary outcomes of this study. Synthesis of main findings from different studies examining the subject issue here may uncover important research gaps in this literature, laying a strong foundation for research and development of sustainable localized migrant-specific HIV prevention strategies in South Africa. Our protocol was registered with PROSPERO under registration number: CRD 42017055580. ( https://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42017055580 ).
Farshidfar, Farnaz; Pinder, Mark A; Myrie, Semone B
2017-01-01
Creatine, a very popular supplement among athletic populations, is of growing interest for clinical applications. Since over 90% of creatine is stored in skeletal muscle, the effect of creatine supplementation on muscle metabolism is a widely studied area. While numerous studies over the past few decades have shown that creatine supplementation has many favorable effects on skeletal muscle physiology and metabolism, including enhancing muscle mass (growth/hypertrophy); the underlying mechanisms are poorly understood. This report reviews studies addressing the mechanisms of action of creatine supplementation on skeletal muscle growth/hypertrophy. Early research proposed that the osmotic effect of creatine supplementation serves as a cellular stressor (osmosensing) that acts as an anabolic stimulus for protein synthesis signal pathways. Other reports indicated that creatine directly affects muscle protein synthesis via modulations of components in the mammalian target of rapamycin (mTOR) pathway. Creatine may also directly affect the myogenic process (formation of muscle tissue), by altering secretions of myokines, such as myostatin and insulin-like growth factor-1, and expressions of myogenic regulatory factors, resulting in enhanced satellite cells mitotic activities and differentiation into myofiber. Overall, there is still no clear understanding of the mechanisms of action regarding how creatine affects muscle mass/growth, but current evidence suggests it may exert its effects through multiple approaches, with converging impacts on protein synthesis and myogenesis. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Patients' expectations of medicines--a review and qualitative synthesis.
Dohnhammar, Ulrica; Reeve, Joanne; Walley, Tom
2016-04-01
An increasing part of prescribing of medicines is done for the purpose of managing risk for disease and is motivated by clinical and economic benefit on a long-term, population level. This makes benefit from medicines less tangible for individuals. Sociology of pharmaceuticals includes personal and social perspectives in the study of how medicines are used. We use two characterizations of patients' expectations of medicines to start forming a description of how individuals conceptualize benefits from risk management medicines. We reviewed the literature on patients' expectations with a focus on the influences on expectations regarding medicines prescribed for long-term conditions. Searches in Medline and Scopus identified 20 studies for inclusion, describing qualitative aspects of beliefs, views, thoughts and expectations regarding medicines. A qualitative synthesis using a constant comparative thematic analysis identified four themes describing influences on expectations: a need to achieve a specific outcome; the development of experiences and evaluation over time; negative values such as dependency and social stigma; and personalized meaning of the necessity and usefulness of medicines. The findings in this synthesis resonate with previous research into expectations of medicines for prevention and treatment of different conditions. However, a gap in the knowledge regarding patients' conceptualization of future benefits with medicines is identified. The study highlights suggestions for further empirical work to develop a deeper understanding of the role of patients' expectations in prescribing for long-term risk management. © 2015 John Wiley & Sons Ltd.
ERIC Educational Resources Information Center
Holt, S.
1972-01-01
Short articles describing a model of protein synthesis, a simple constant temperature incubator, techniques for determining the age structure of populations from qualitative characters, an experimental demonstration of proteolytic enzyme action, and apparatus for demonstrating hydrotrophic response of roots and for measuring photosynthetic rate of…
Protein turnover, amino acid requirements and recommendations for athletes and active populations
Poortmans, J.R.; Carpentier, A.; Pereira-Lancha, L.O.; Lancha, A.
2012-01-01
Skeletal muscle is the major deposit of protein molecules. As for any cell or tissue, total muscle protein reflects a dynamic turnover between net protein synthesis and degradation. Noninvasive and invasive techniques have been applied to determine amino acid catabolism and muscle protein building at rest, during exercise and during the recovery period after a single experiment or training sessions. Stable isotopic tracers (13C-lysine, 15N-glycine, 2H5-phenylalanine) and arteriovenous differences have been used in studies of skeletal muscle and collagen tissues under resting and exercise conditions. There are different fractional synthesis rates in skeletal muscle and tendon tissues, but there is no major difference between collagen and myofibrillar protein synthesis. Strenuous exercise provokes increased proteolysis and decreased protein synthesis, the opposite occurring during the recovery period. Individuals who exercise respond differently when resistance and endurance types of contractions are compared. Endurance exercise induces a greater oxidative capacity (enzymes) compared to resistance exercise, which induces fiber hypertrophy (myofibrils). Nitrogen balance (difference between protein intake and protein degradation) for athletes is usually balanced when the intake of protein reaches 1.2 g·kg−1·day−1 compared to 0.8 g·kg−1·day−1 in resting individuals. Muscular activities promote a cascade of signals leading to the stimulation of eukaryotic initiation of myofibrillar protein synthesis. As suggested in several publications, a bolus of 15-20 g protein (from skimmed milk or whey proteins) and carbohydrate (± 30 g maltodextrine) drinks is needed immediately after stopping exercise to stimulate muscle protein and tendon collagen turnover within 1 h. PMID:22666780
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tomkins, D.J.; Wei, L.; Laurie, K.E.
1985-01-01
It has been shown that circulating peripheral blood lymphocytes can be used for the enumeration of 6-thioguanine-resistant cells that presumably arise by mutation in vivo. This somatic cell mutation test has been studied in lymphocytes from human populations exposed to known mutagens and/or carcinogens. The sensitivity of the test could be further enhanced by including other gene markers, since there is evidence for locus-specific differences in response to mutagens. Resistance to diphtheria toxin (Dip/sup r/) seemed like a potential marker to incorporate into the test because the mutation acts codominantly, can readily be selected in human diploid fibroblasts and Chinesemore » hamster cells with no evidence for cell density or cross-feeding effects, and can be assayed for in nondividing cells by measuring protein synthesis inhibition. Blood samples were collected from seven individuals, and fresh, cryopreserved, or Epstein-Barr virus (EBV)-transformed lymphocytes were tested for continued DNA synthesis (TH-thymidine, autoradiography) or protein synthesis (TVS-methionine, scintillation counting). Both fresh and cryopreserved lymphocytes, stimulated to divide with phytohemagglutinin (PHA), continued to synthesize DNA in the presence of high doses of diphtheria toxin (DT). Similarly, both dividing (PHA-stimulated) and nondividing fresh lymphocytes carried on significant levels of protein synthesis even 68 hr after exposure to 100 flocculating units (LF)/ml DT. The results suggest that human T and B lymphocytes may not be as sensitive to DT protein synthesis inhibition as human fibroblast and Chinese hamster cells. For this reason, Dip/sup r/ may not be a suitable marker for the somatic cell mutation test.« less
Crowell, Kristen T; Kelleher, Shannon L; Soybel, David I; Lang, Charles H
2016-11-01
Severe zinc deficiency is associated with an increased systemic inflammatory response and mortality after sepsis. However, the impact of mild zinc deficiency, which is more common in populations with chronic illnesses and sepsis, is unknown. In this study, we hypothesized that marginal dietary Zn deprivation (ZM) would amplify tissue inflammation and exacerbate the sepsis-induced decrease in muscle protein synthesis. Adult male C57BL/6 mice were fed a zinc-adequate (ZA) or ZM diet (30 or 10 mg Zn/kg, respectively) over 4 weeks, peritonitis was induced by cecal ligation and puncture (CLP), and mice were examined at either 24 h (acute) or 5 days (chronic) post-CLP Acute sepsis decreased the in vivo rate of skeletal muscle protein synthesis and the phosphorylation of the mTOR substrate 4E-BP1. Acutely, sepsis increased TNF-α and IL-6 mRNA in muscle, and the increase in TNF-α was significantly greater in ZM mice. However, muscle protein synthesis and 4E-BP1 phosphorylation returned to baseline 5 days post-CLP in both ZA and ZM mice. Protein degradation via markers of the ubiquitin proteasome pathway was increased in acute sepsis, yet only MuRF1 mRNA was increased in chronic sepsis and ZM amplified this elevation. Our data suggest that mild zinc deficiency increases TNF-α in muscle acutely after sepsis but does not significantly modulate the rate of muscle protein synthesis. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.
NASA Astrophysics Data System (ADS)
Bernhard, E.; Mullaney, J. R.; Aird, J.; Hickox, R. C.; Jones, M. L.; Stanley, F.; Grimmett, L. P.; Daddi, E.
2018-05-01
The lack of a strong correlation between AGN X-ray luminosity (LX; a proxy for AGN power) and the star formation rate (SFR) of their host galaxies has recently been attributed to stochastic AGN variability. Studies using population synthesis models have incorporated this by assuming a broad, universal (i.e. does not depend on the host galaxy properties) probability distribution for AGN specific X-ray luminosities (i.e. the ratio of LX to host stellar mass; a common proxy for Eddington ratio). However, recent studies have demonstrated that this universal Eddington ratio distribution fails to reproduce the observed X-ray luminosity functions beyond z ˜ 1.2. Furthermore, empirical studies have recently shown that the Eddington ratio distribution may instead depend upon host galaxy properties, such as SFR and/or stellar mass. To investigate this further, we develop a population synthesis model in which the Eddington ratio distribution is different for star-forming and quiescent host galaxies. We show that, although this model is able to reproduce the observed X-ray luminosity functions out to z ˜ 2, it fails to simultaneously reproduce the observed flat relationship between SFR and X-ray luminosity. We can solve this, however, by incorporating a mass dependency in the AGN Eddington ratio distribution for star-forming host galaxies. Overall, our models indicate that a relative suppression of low Eddington ratios (λEdd ≲ 0.1) in lower mass galaxies (M* ≲ 1010 - 11 M⊙) is required to reproduce both the observed X-ray luminosity functions and the observed flat SFR/X-ray relationship.
Kim, Hyejin; Song, Mi-Kyung
2018-01-01
Adults who lack decision-making capacity and a surrogate ("unbefriended" adults) are a vulnerable, voiceless population in health care. But little is known about this population, including how medical decisions are made for these individuals. This integrative review was to examine what is known about unbefriended adults and identify gaps in the literature. Six electronic databases were searched using 4 keywords: "unbefriended," "unrepresented patients," "adult orphans," and "incapacitated patients without surrogates." After screening, the final sample included 10 data-based articles for synthesis. Main findings include the following: (1) various terms were used to refer to adults who lack decision-making capacity and a surrogate; (2) the number of unbefriended adults was sizable and likely to grow; (3) approaches to medical decision-making for this population in health-care settings varied; and (4) professional guidelines and laws to address the issues related to this population were inconsistent. There have been no studies regarding the quality of medical decision-making and its outcomes for this population or societal impact. Extremely limited empirical data exist on unbefriended adults to develop strategies to improve how medical decisions are made for this population. There is an urgent need for research to examine the quality of medical decision-making and its outcomes for this vulnerable population.
Incidence of Venous Thromboembolism in Asian Populations: A Systematic Review.
Lee, Lai Heng; Gallus, Alexander; Jindal, Ravul; Wang, Chen; Wu, Chau-Chung
2017-12-01
Introduction Despite a marked recent increase in the number of publications describing the incidence of venous thromboembolism (VTE) in Asia, and especially in mainland China, Hong Kong, Taiwan, Korea, Japan and Singapore, there remains a lack of consensus on the true risks, and trends over time, to inform appropriate clinical practice. The purpose of this systematic review was therefore to examine evidence about the incidence of symptomatic VTE in Asia. Methods Databases were searched for studies from Asia, published between January 1995 and February 2016, on the incidence of symptomatic VTE, deep vein thrombosis (DVT) or pulmonary embolism. Review of eligible studies was conducted independently by two reviewers. Data were extracted on incidence, predispositions and recurrence of VTE. Results One thousand nighty-five studies were identified, of which 73 were eligible for full text review and data extraction. Three population-wide estimates of VTE rates identified from Korea, Taiwan and Hong Kong reported annual incidences of 13.8, 15.9 and 19.9 per 100,000, respectively. Nine studies of Asian hospital registries or databases reported VTE rates ranging from 11 to 88 cases per 10,000 admissions. Population-based estimates of post-surgical DVT rates ranged from 0.15 to 1.35%. Age was a significant risk factor for VTE in all population groups. Conclusion Population-wide incidence estimates in Asia were approximately 15 to 20% of the levels recorded in western countries but have increased over time. It is anticipated this synthesis of evidence on the incidence of VTE and its predisposing factors will increase awareness about VTE in Asian populations.
Guo, Huijun; Liu, Yunchuan; Li, Xiao; Yan, Zhihui; Xie, Yongdun; Xiong, Hongchun; Zhao, Linshu; Gu, Jiayu; Zhao, Shirong; Liu, Luxiang
2017-05-08
Transient starch provides carbon and energy for plant growth, and its synthesis is regulated by the joint action of a series of enzymes. Starch synthesis IV (SSIV) is one of the important starch synthase isoforms, but its impact on wheat starch synthesis has not yet been reported due to the lack of mutant lines. Using the TILLING approach, we identified 54 mutations in the wheat gene TaSSIVb-D, with a mutation density of 1/165 Kb. Among these, three missense mutations and one nonsense mutation were predicted to have severe impacts on protein function. In the mutants, TaSSIVb-D was significantly down-regulated without compensatory increases in the homoeologous genes TaSSIVb-A and TaSSIVb-B. Altered expression of TaSSIVb-D affected granule number per chloroplast; compared with wild type, the number of chloroplasts containing 0-2 granules was significantly increased, while the number containing 3-4 granules was decreased. Photosynthesis was affected accordingly; the maximum quantum yield and yield of PSII were significantly reduced in the nonsense mutant at the heading stage. These results indicate that TaSSIVb-D plays an important role in the formation of transient starch granules in wheat, which in turn impact the efficiency of photosynthesis. The mutagenized population created in this study allows the efficient identification of novel alleles of target genes and could be used as a resource for wheat functional genomics.
Rapid synthesis of acetylcholine receptors at neuromuscular junctions.
Ramsay, D A; Drachman, D B; Pestronk, A
1988-10-11
The rate of acetylcholine receptor (AChR) degradation in mature, innervated mammalian neuromuscular junctions has recently been shown to be biphasic; up to 20% are rapidly turned over (RTOs; half life less than 1 day) whereas the remainder are lost more slowly ('stable' AChRs; half life 10-12 days). In order to maintain normal junctional receptor density, synthesis and insertion of AChRs should presumably be sufficiently rapid to replace both the RTOs and the stable receptors. We have tested this prediction by blocking pre-existing AChRs in the mouse sternomastoid muscle with alpha-bungarotoxin (alpha-BuTx), and monitoring the subsequent appearance of 'new' junctional AChRs at intervals of 3 h to 20 days by labeling them with 125I-alpha-BuTx. The results show that new receptors were initially inserted rapidly (16% at 24 h and 28% at 48 h). The rate of increase of 'new' 125I-alpha-BuTx binding sites gradually slowed down during the remainder of the time period studied. Control observations excluded possible artifacts of the experimental procedure including incomplete blockade of AChRs, dissociation of toxin-receptor complexes, or experimentally induced alteration of receptor synthesis. The present demonstration of rapid synthesis and incorporation of AChRs at innervated neuromuscular junctions provides support for the concept of a subpopulation of rapidly turned over AChRs. The RTOs may serve as precursors for the larger population of stable receptors and have an important role in the metabolism of the neuromuscular synapse.
2016-01-01
Protein metabolism, consisting of both synthesis and degradation, is highly complex, playing an indispensable regulatory role throughout physiological and pathological processes. Over recent decades, extensive efforts, using approaches such as autoradiography, mass spectrometry, and fluorescence microscopy, have been devoted to the study of protein metabolism. However, noninvasive and global visualization of protein metabolism has proven to be highly challenging, especially in live systems. Recently, stimulated Raman scattering (SRS) microscopy coupled with metabolic labeling of deuterated amino acids (D-AAs) was demonstrated for use in imaging newly synthesized proteins in cultured cell lines. Herein, we significantly generalize this notion to develop a comprehensive labeling and imaging platform for live visualization of complex protein metabolism, including synthesis, degradation, and pulse–chase analysis of two temporally defined populations. First, the deuterium labeling efficiency was optimized, allowing time-lapse imaging of protein synthesis dynamics within individual live cells with high spatial–temporal resolution. Second, by tracking the methyl group (CH3) distribution attributed to pre-existing proteins, this platform also enables us to map protein degradation inside live cells. Third, using two subsets of structurally and spectroscopically distinct D-AAs, we achieved two-color pulse–chase imaging, as demonstrated by observing aggregate formation of mutant hungtingtin proteins. Finally, going beyond simple cell lines, we demonstrated the imaging ability of protein synthesis in brain tissues, zebrafish, and mice in vivo. Hence, the presented labeling and imaging platform would be a valuable tool to study complex protein metabolism with high sensitivity, resolution, and biocompatibility for a broad spectrum of systems ranging from cells to model animals and possibly to humans. PMID:25560305
Lee, Janet Lok Chun; Lo, Temmy Lee Ting
2018-01-01
(1) Background: An outdoor gym (OG) is environmental infrastructure built in a public open space to promote structured physical activity. The provision of OGs is increasingly seen as an important strategy to realize public health agendas promoting habitual physical activity. A systematic review was conducted to synthesize characteristics of OG and OG users’ experiences and perceptions in different cultural contexts; (2) Methods: Online searches of multidisciplinary databases were conducted in health, sport and recreation, and urban planning disciplines. Characteristics of OGs were synthesized by integrating evidence from quantitative, qualitative, and mix-methods studies. The experiences and perceptions of OG users from both qualitative data and survey responses were synthesized through framework analysis; (3) Results: Nine studies met the inclusion criteria (three quantitative studies, four mixed-methods studies, and two pure qualitative studies). None were excluded on the basis of quality. OGs mainly serve adult and older adult population groups. Their size, design, and instructional support vary across studies. The inclusion of functional types of equipment did not have a unified standard. Regarding experiences and perceptions of OGs, five major themes emerged: “health”, “social connectedness”, “affordable”, “support”, and “design and promotion”; (4) Conclusions: The OG characteristics synthesis guides the direction in further studies regarding exploration of design parameters. The qualitative and quantitative synthesis revealed that health was a central theme of users’ experiences. OGs are also spaces where community-dwellers can find social connectedness while participating in structured physical activity at no cost. Findings from this review create knowledge support for OG as environmental infrastructure for further research and facilitate the understanding of users’ experiences and perceptions of OGs in different cultural contexts. PMID:29587402
Ecology and conservation of North American sea ducks
Savard, Jean-Pierre L.; Derksen, Dirk V.; Esler, Daniel N.; Eadie, John M.
2015-01-01
Harvest history The book presents a comprehensive synthesis of sea duck ecology, documents factors that have caused population declines of some species, and provides managers with measures to enhance recovery of depressed populations of sea ducks in North America. Capturing the current state of knowledge of this unique tribe, it provides a benchmark for where we are in conservation efforts and suggests future directions for researchers, managers, students, conservationists, and avian enthusiasts.
Achenbach, Chad J.; O’Dwyer, Linda C.; Evans, Charlesnika T.; McHugh, Megan; Hou, Lifang; Simon, Melissa A.; Murphy, Robert L.; Jordan, Neil
2017-01-01
Background Although cervical cancer is largely preventable through screening, detection and treatment of precancerous abnormalities, it remains one of the top causes of cancer-related morbidity and mortality globally. Objectives The objective of this systematic review is to understand the evidence of the effect of cervical cancer education compared to control conditions on cervical cancer screening rates in eligible women population at risk of cervical cancer. We also sought to understand the effect of provider recommendations for screening to eligible women on cervical cancer screening (CCS) rates compared to control conditions in eligible women population at risk of cervical cancer. Methods We used the PICO (Problem or Population, Interventions, Comparison and Outcome) framework as described in the Cochrane Collaboration Handbook to develop our search strategy. The details of our search strategy has been described in our systematic review protocol published in the International Prospective Register of systematic reviews (PROSPERO). The protocol registration number is CRD42016045605 available at: http://www.crd.york.ac.uk/prospero/display_record.asp?src=trip&ID=CRD42016045605. The search string was used in Pubmed, Embase, Cochrane Systematic Reviews and Cochrane CENTRAL register of controlled trials to retrieve study reports that were screened for inclusion in this review. Our data synthesis and reporting was guided by the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). We did a qualitative synthesis of evidence and, where appropriate, individual study effects were pooled in meta-analyses using RevMan 5.3 Review Manager. The Higgins I2 was used to assess for heterogeneity in studies pooled together for overall summary effects. We did assessment of risk of bias of individual studies included and assessed risk of publication bias across studies pooled together in meta-analysis by Funnel plot. Results Out of 3072 study reports screened, 28 articles were found to be eligible for inclusion in qualitative synthesis (5 of which were included in meta-analysis of educational interventions and 8 combined in meta-analysis of HPV self-sampling interventions), while 45 were excluded for various reasons. The use of theory-based educational interventions significantly increased CCS rates by more than double (OR, 2.46, 95% CI: 1.88, 3.21). Additionally, offering women the option of self-sampling for Human Papillomavirus (HPV) testing increased CCS rates by nearly 2-fold (OR = 1.71, 95% CI: 1.32, 2.22). We also found that invitation letters alone (or with a follow up phone contact), making an appointment, and sending reminders to patients who are due or overdue for screening had a significant effect on improving participation and CCS rates in populations at risk. Conclusion Our findings supports the implementation of theory-based cervical cancer educational interventions to increase women’s participation in cervical cancer screening programs, particularly when targeting communities with low literacy levels. Additionally, cervical cancer screening programs should consider the option of offering women the opportunity for self-sample collection particularly when such women have not responded to previous screening invitation or reminder letters for Pap smear collection as a method of screening. PMID:28873092
Musa, Jonah; Achenbach, Chad J; O'Dwyer, Linda C; Evans, Charlesnika T; McHugh, Megan; Hou, Lifang; Simon, Melissa A; Murphy, Robert L; Jordan, Neil
2017-01-01
Although cervical cancer is largely preventable through screening, detection and treatment of precancerous abnormalities, it remains one of the top causes of cancer-related morbidity and mortality globally. The objective of this systematic review is to understand the evidence of the effect of cervical cancer education compared to control conditions on cervical cancer screening rates in eligible women population at risk of cervical cancer. We also sought to understand the effect of provider recommendations for screening to eligible women on cervical cancer screening (CCS) rates compared to control conditions in eligible women population at risk of cervical cancer. We used the PICO (Problem or Population, Interventions, Comparison and Outcome) framework as described in the Cochrane Collaboration Handbook to develop our search strategy. The details of our search strategy has been described in our systematic review protocol published in the International Prospective Register of systematic reviews (PROSPERO). The protocol registration number is CRD42016045605 available at: http://www.crd.york.ac.uk/prospero/display_record.asp?src=trip&ID=CRD42016045605. The search string was used in Pubmed, Embase, Cochrane Systematic Reviews and Cochrane CENTRAL register of controlled trials to retrieve study reports that were screened for inclusion in this review. Our data synthesis and reporting was guided by the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). We did a qualitative synthesis of evidence and, where appropriate, individual study effects were pooled in meta-analyses using RevMan 5.3 Review Manager. The Higgins I2 was used to assess for heterogeneity in studies pooled together for overall summary effects. We did assessment of risk of bias of individual studies included and assessed risk of publication bias across studies pooled together in meta-analysis by Funnel plot. Out of 3072 study reports screened, 28 articles were found to be eligible for inclusion in qualitative synthesis (5 of which were included in meta-analysis of educational interventions and 8 combined in meta-analysis of HPV self-sampling interventions), while 45 were excluded for various reasons. The use of theory-based educational interventions significantly increased CCS rates by more than double (OR, 2.46, 95% CI: 1.88, 3.21). Additionally, offering women the option of self-sampling for Human Papillomavirus (HPV) testing increased CCS rates by nearly 2-fold (OR = 1.71, 95% CI: 1.32, 2.22). We also found that invitation letters alone (or with a follow up phone contact), making an appointment, and sending reminders to patients who are due or overdue for screening had a significant effect on improving participation and CCS rates in populations at risk. Our findings supports the implementation of theory-based cervical cancer educational interventions to increase women's participation in cervical cancer screening programs, particularly when targeting communities with low literacy levels. Additionally, cervical cancer screening programs should consider the option of offering women the opportunity for self-sample collection particularly when such women have not responded to previous screening invitation or reminder letters for Pap smear collection as a method of screening.
Constraining Roche-Lobe Overflow Models Using the Hot-Subdwarf Wide Binary Population
NASA Astrophysics Data System (ADS)
Vos, Joris; Vučković, Maja
2017-12-01
One of the important issues regarding the final evolution of stars is the impact of binarity. A rich zoo of peculiar, evolved objects are born from the interaction between the loosely bound envelope of a giant, and the gravitational pull of a companion. However, binary interactions are not understood from first principles, and the theoretical models are subject to many assumptions. It is currently agreed upon that hot subdwarf stars can only be formed through binary interaction, either through common envelope ejection or stable Roche-lobe overflow (RLOF) near the tip of the red giant branch (RGB). These systems are therefore an ideal testing ground for binary interaction models. With our long term study of wide hot subdwarf (sdB) binaries we aim to improve our current understanding of stable RLOF on the RGB by comparing the results of binary population synthesis studies with the observed population. In this article we describe the current model and possible improvements, and which observables can be used to test different parts of the interaction model.
Joplin, R E; Franchi, L L; Salmons, S
1987-01-01
The adaptive response of mammalian fast-twitch skeletal muscle to long-term low-frequency stimulation involves coordinated changes in the expression of a large number of genes and an increase in the synthesis of proteins and nucleic acids. Morphological correlates of these changes were sought in a qualitative and quantitative study of nuclear populations that included autoradiography at both light and electron microscopic levels. Stimulation-induced changes in biosynthetic activity were found to be supported by increases in the numbers of both non-muscle and muscle nuclei, and myonuclear counts were significantly increased in relation to sarcoplasmic volume. Moreover, the chronically stimulated muscle fibres showed ultrastructural signs consistent with mobilisation of transcriptional and translational activity. Images Fig. 2 Fig. 4 (cont.) Fig. 4 Fig. 5 PMID:3503051
ACS Presents Science Education Report to Congress.
ERIC Educational Resources Information Center
Krieger, James
1989-01-01
Discusses an American Chemical Society (ACS)'s report on science education which is a synthesis of a series of policies developed by ACS. Summarizes recommendations in four areas: elementary teacher education; pre-high school curricula; university research funding; and underrepresented populations. (YP)
Pereira, Tiago V; Mingroni-Netto, Regina C
2011-06-06
The generalized odds ratio (GOR) was recently suggested as a genetic model-free measure for association studies. However, its properties were not extensively investigated. We used Monte Carlo simulations to investigate type-I error rates, power and bias in both effect size and between-study variance estimates of meta-analyses using the GOR as a summary effect, and compared these results to those obtained by usual approaches of model specification. We further applied the GOR in a real meta-analysis of three genome-wide association studies in Alzheimer's disease. For bi-allelic polymorphisms, the GOR performs virtually identical to a standard multiplicative model of analysis (e.g. per-allele odds ratio) for variants acting multiplicatively, but augments slightly the power to detect variants with a dominant mode of action, while reducing the probability to detect recessive variants. Although there were differences among the GOR and usual approaches in terms of bias and type-I error rates, both simulation- and real data-based results provided little indication that these differences will be substantial in practice for meta-analyses involving bi-allelic polymorphisms. However, the use of the GOR may be slightly more powerful for the synthesis of data from tri-allelic variants, particularly when susceptibility alleles are less common in the populations (≤10%). This gain in power may depend on knowledge of the direction of the effects. For the synthesis of data from bi-allelic variants, the GOR may be regarded as a multiplicative-like model of analysis. The use of the GOR may be slightly more powerful in the tri-allelic case, particularly when susceptibility alleles are less common in the populations.
Zhao, X H; Liu, C J; Liu, Y; Li, C Y; Yao, J H
2013-12-01
A rumen simulation technique (RUSITEC) apparatus with eight 800 ml fermenters was used to investigate the effects of replacing dietary starch with neutral detergent-soluble fibre (NDSF) by inclusion of sugar beet pulp in diets on ruminal fermentation, microbial synthesis and populations of ruminal cellulolytic bacteria. Experimental diets contained 12.7, 16.4, 20.1 or 23.8% NDSF substituted for starch on a dry matter basis. The experiment was conducted over two independent 15-day incubation periods with the last 8 days used for data collection. There was a tendency that 16.4% NDSF in the diet increased the apparent disappearance of organic matter (OM) and neutral detergent fibre (NDF). Increasing dietary NDSF level increased carboxymethylcellulase and xylanase activity in the solid fraction and apparent disappearance of acid detergent fibre (ADF) but reduced the 16S rDNA copy numbers of Ruminococcus albus in both liquid and solid fractions and R. flavefaciens in the solid fraction. The apparent disappearance of dietary nitrogen (N) was reduced by 29.6% with increased dietary NDSF. Substituting NDSF for starch appeared to increase the ratios of acetate/propionate and methane/volatile fatty acids (VFA) (mol/mol). Replacing dietary starch with NDSF reduced the daily production of ammonia-N and increased the growth of the solid-associated microbial pellets (SAM). Total microbial N flow and efficiency of microbial synthesis (EMS), expressed as g microbial N/kg OM fermented, tended to increase with increased dietary NDSF, but the numerical increase did not continue as dietary NDSF exceeded 20.1% of diet DM. Results suggested that substituting NDSF for starch up to 16.4% of diet DM increased digestion of nutrients (except for N) and microbial synthesis, and further increases (from 16.4% to 23.8%) in dietary NDSF did not repress microbial synthesis but did significantly reduce digestion of dietary N. © 2012 Blackwell Verlag GmbH.
Population size estimation of female sex workers in Iran: Synthesis of methods and results.
Sharifi, Hamid; Karamouzian, Mohammad; Baneshi, Mohammad Reza; Shokoohi, Mostafa; Haghdoost, AliAkbar; McFarland, Willi; Mirzazadeh, Ali
2017-01-01
Estimating the number of key populations at risk of HIV is essential for planning, monitoring, and evaluating prevention, care, and treatment programmes. We conducted this study to estimate the number of female sex workers (FSW) in major cities of Iran. We used three population size estimation methods (i.e., wisdom of the crowds, multiplier method, and network scale-up) to calculate the number of FSW in 13 cities in Iran. The wisdom of the crowds and multiplier methods were integrated into a nationwide bio-behavioural surveillance survey in 2015, and the network scale-up method was included in a national survey of the general population in 2014. The median of the three methods was used to calculate the proportion of the adult female population who practice sex work in the 13 cities. These figures were then extrapolated to provide a national population size estimation of FSW across urban areas. The population size of FSW was 91,500 (95% Uncertainty Intervals [UIs] 61,400-117,700), corresponding to 1.43% (95% UIs 0.96-1.84) of the adult (i.e., 15-49 year-old) female population living in these 13 cities. The projected numbers of FSW for all 31 provincial capital cities were 130,800 (95% UIs 87,800-168,200) and 228,700 (95% UIs 153,500-294,300) for all urban settings in Iran. Using methods of comparable rigor, our study provided a data-driven national estimate of the population size of FSW in urban areas of Iran. Our findings provide vital information for enhancing HIV programme planning and lay a foundation for assessing the impact of harm reduction efforts within this marginalized population.
Population size estimation of female sex workers in Iran: Synthesis of methods and results
Sharifi, Hamid; Karamouzian, Mohammad; Baneshi, Mohammad Reza; Shokoohi, Mostafa; Haghdoost, AliAkbar; McFarland, Willi
2017-01-01
Introduction Estimating the number of key populations at risk of HIV is essential for planning, monitoring, and evaluating prevention, care, and treatment programmes. We conducted this study to estimate the number of female sex workers (FSW) in major cities of Iran. Methods We used three population size estimation methods (i.e., wisdom of the crowds, multiplier method, and network scale-up) to calculate the number of FSW in 13 cities in Iran. The wisdom of the crowds and multiplier methods were integrated into a nationwide bio-behavioural surveillance survey in 2015, and the network scale-up method was included in a national survey of the general population in 2014. The median of the three methods was used to calculate the proportion of the adult female population who practice sex work in the 13 cities. These figures were then extrapolated to provide a national population size estimation of FSW across urban areas. Results The population size of FSW was 91,500 (95% Uncertainty Intervals [UIs] 61,400–117,700), corresponding to 1.43% (95% UIs 0.96–1.84) of the adult (i.e., 15–49 year-old) female population living in these 13 cities. The projected numbers of FSW for all 31 provincial capital cities were 130,800 (95% UIs 87,800–168,200) and 228,700 (95% UIs 153,500–294,300) for all urban settings in Iran. Conclusions Using methods of comparable rigor, our study provided a data-driven national estimate of the population size of FSW in urban areas of Iran. Our findings provide vital information for enhancing HIV programme planning and lay a foundation for assessing the impact of harm reduction efforts within this marginalized population. PMID:28796847
Beliefs and perception about mental health issues: a meta-synthesis.
Choudhry, Fahad Riaz; Mani, Vasudevan; Ming, Long Chiau; Khan, Tahir Mehmood
2016-01-01
Mental health literacy is the beliefs and knowledge about mental health issues and their remedies. Attitudes and beliefs of lay individuals about mental illness are shaped by personal knowledge about mental illness, knowing and interacting with someone living with mental illness, and cultural stereotypes. Mental health issues are increasing and are alarming in almost every part of the world, and hence compiling this review provides an opportunity to understand the different views regarding mental disorders and problems as well as to fill the gap in the published literature by focusing only on the belief system and perception of mental health problems among general population. The methodology involved a systematic review and the meta-synthesis method, which includes synthesizing published qualitative studies on mental health perception and beliefs. Fifteen relevant published qualitative and mixed-method studies, regarding the concept of mental health, were identified for meta-synthesis. All the themes of the selected studies were further analyzed to give a broader picture of mental health problems and their perceived causes and management. Only qualitative studies, not older than 2010, focusing on beliefs about, attitudes toward, and perceptions of mental health problems, causes, and treatments were included in this review. The findings are divided into four major categories, namely, 1) symptoms of mental health issues, 2) description of mental health issues, 3) perceived causes, and 4) preferred treatment and help-seeking behavior. Each category contains themes and subthemes based on published studies. The findings reveal multiple causes of, descriptions of, and treatment options for mental health problems, thereby providing insight into different help-seeking behaviors. Clarity is offered by highlighting cultural differences and similarities in mental health beliefs and perceptions about the causes of mental health problems. The implications of the studies and recommendations based on current findings are also discussed.
Becker, Betsy Jane; Aloe, Ariel M; Duvendack, Maren; Stanley, T D; Valentine, Jeffrey C; Fretheim, Atle; Tugwell, Peter
2017-09-01
To outline issues of importance to analytic approaches to the synthesis of quasi-experiments (QEs) and to provide a statistical model for use in analysis. We drew on studies of statistics, epidemiology, and social-science methodology to outline methods for synthesis of QE studies. The design and conduct of QEs, effect sizes from QEs, and moderator variables for the analysis of those effect sizes were discussed. Biases, confounding, design complexities, and comparisons across designs offer serious challenges to syntheses of QEs. Key components of meta-analyses of QEs were identified, including the aspects of QE study design to be coded and analyzed. Of utmost importance are the design and statistical controls implemented in the QEs. Such controls and any potential sources of bias and confounding must be modeled in analyses, along with aspects of the interventions and populations studied. Because of such controls, effect sizes from QEs are more complex than those from randomized experiments. A statistical meta-regression model that incorporates important features of the QEs under review was presented. Meta-analyses of QEs provide particular challenges, but thorough coding of intervention characteristics and study methods, along with careful analysis, should allow for sound inferences. Copyright © 2017 Elsevier Inc. All rights reserved.
Spheroidal Populated Star Systems
NASA Astrophysics Data System (ADS)
Angeletti, Lucio; Giannone, Pietro
2008-10-01
Globular clusters and low-ellipticity early-type galaxies can be treated as systems populated by a large number of stars and whose structures can be schematized as spherically symmetric. Their studies profit from the synthesis of stellar populations. The computation of synthetic models makes use of various contributions from star evolution and stellar dynamics. In the first sections of the paper we present a short review of our results on the occurrence of galactic winds in star systems ranging from globular clusters to elliptical galaxies, and the dynamical evolution of a typical massive globular cluster. In the subsequent sections we describe our approach to the problem of the stellar populations in elliptical galaxies. The projected radial behaviours of spectro-photometric indices for a sample of eleven galaxies are compared with preliminary model results. The best agreement between observation and theory shows that our galaxies share a certain degree of heterogeneity. The gas energy dissipation varies from moderate to large, the metal yield ranges from solar to significantly oversolar, the dispersion of velocities is isotropic in most of the cases and anisotropic in the remaining instances.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yano, K.; Morimasa, K.; Asano, T.
1985-04-01
Characterization of the cells responsible for spontaneous DNA synthesis and/or IgG secretion in systemic lupus erythematosus (SLE) was undertaken by fractionation of the peripheral blood mononuclear cells (PBM). Each fraction was analyzed for its capacity to incorporate (/sup 3/H)thymidine ((/sup 3/H)TdR) and secrete IgG without mitogen. The non-E rosette-forming cell (non-ERRC) fraction, which consisted of the surface immunoglobulin-positive (sIg(+)) cells and null cells, revealed a markedly increased spontaneous DNA synthesis (620.0 +/- 586.9 cpm) during the first hour of culture and an elevated spontaneous IgG secretion (8639 +/- 2630 ng/ml) during 9 days of culture. Of particular interest was themore » finding that both increased responses were conducted by the null cells; the null cell population had approximately a fourfold relative increase of (/sup 3/H)TdR incorporation and a 60-fold relative increase of IgG secretion compared with the sIg(+) cell population. These results suggest that SLE patients have a small population of preactivated B-cell lineage cells, which lack sIg or have a very low density of sIg.« less
Hagen, Joel B
2015-01-01
During the decades following World War II diverse groups of American biologists established a variety of distinctive approaches to organismal biology. Rhetorically, organismal biology could be used defensively to distinguish established research traditions from perceived threats from newly emerging fields such as molecular biology. But, organismal biologists were also interested in integrating biological disciplines and using a focus on organisms to synthesize levels of organization from molecules and cells to populations and communities. Part of this broad movement was the development of an area of research variously referred to as physiological ecology, environmental physiology, or ecophysiology. This area of research was distinctive in its self-conscious blend of field and laboratory practices and its explicit integration with other areas of biology such as ecology, animal behavior, and evolution in order to study adaptation. Comparing the intersecting careers of Knut Schmidt-Nielsen and George Bartholomew highlights two strikingly different approaches to physiological ecology. These alternative approaches to studying the interactions of organisms and environments also differed in important ways from the organismal biology championed by leading figures in the modern synthesis.
McGregor, Lesley M.; Heinrich, Małgorzata; von Wagner, Christian; Waller, Jo; Wardle, Jane; Black, Georgia B.
2016-01-01
Abstract Background Cancer has long inspired fear, but the effect of fear is not well understood; it seems both to facilitate and to deter early diagnosis behaviours. To elucidate fear's behavioural effects, we systematically reviewed and synthesised qualitative literature to explore what people fear about cancer. Methods We searched Medline, Embase, PsycInfo, Web of Science, AnthroSource, and Anthrobase for studies on cancer fear in breast, cervical, and colorectal cancer screening and analysed 102 studies from 26 countries using thematic synthesis. Results Fears of cancer emanated from a core view of cancer as a vicious, unpredictable, and indestructible enemy, evoking fears about its proximity, the (lack of) strategies to keep it at bay, the personal and social implications of succumbing, and fear of dying from cancer. Conclusions This view of cancer as ‘an enemy’ reprises the media's ‘war on cancer’ theme and may affect the acceptance of cancer early detection and prevention messages, since cancer's characteristics influenced whether ‘fight’ or ‘flight’ was considered appropriate. PMID:27643482
Vrinten, Charlotte; McGregor, Lesley M; Heinrich, Małgorzata; von Wagner, Christian; Waller, Jo; Wardle, Jane; Black, Georgia B
2017-08-01
Cancer has long inspired fear, but the effect of fear is not well understood; it seems both to facilitate and to deter early diagnosis behaviours. To elucidate fear's behavioural effects, we systematically reviewed and synthesised qualitative literature to explore what people fear about cancer. We searched Medline, Embase, PsycInfo, Web of Science, AnthroSource, and Anthrobase for studies on cancer fear in breast, cervical, and colorectal cancer screening and analysed 102 studies from 26 countries using thematic synthesis. Fears of cancer emanated from a core view of cancer as a vicious, unpredictable, and indestructible enemy, evoking fears about its proximity, the (lack of) strategies to keep it at bay, the personal and social implications of succumbing, and fear of dying from cancer. This view of cancer as 'an enemy' reprises the media's 'war on cancer' theme and may affect the acceptance of cancer early detection and prevention messages, since cancer's characteristics influenced whether 'fight' or 'flight' was considered appropriate. © 2016 The Authors. Psycho-Oncology Published by John Wiley & Sons Ltd.
Goryshina, E N
1980-07-01
A supposed life-span of hemosiderin-containing macrophages in the frog spleen has been described on the basis of their morphology, changes in the number of nuclei, and results of autoradiographic studies of DNA synthesis in various seasons. The hibernating stages of the lines are hemocytoblasts, mononuclear and moderately polynuclear macrophages, which renew the phagocytosis and nuclear division at the beginning of spring. A new population of monomuclear macrophages develops from hemocytoblasts during spring. Large polynuclear forms appear during spring and summer, reach their maximal size and erythrophagocytotic activity towards the end of summer, and die in winter. The most part of the stored pigments is removed from the spleen. DNA synthesis and division occur asynchronously in the nuclei of one cell. Some pathologic forms of macrophages are described. The similarity in the proliferation cell kinetics of neutrophilic and macrophagal lines confirms a close relation between the two. The role of temperature and photoperiod in the regulations of proliferative activity of these cells during spring is discussed.
Knowledge synthesis and the Canadian Institutes of Health Research
2012-01-01
The Canadian Institutes of Health Research (CIHR) is Canada's premier health-research funding agency. We fund nearly 14,000 researchers and trainees in four theme areas: biomedical, clinical, health services, and population and public-health research. Our mandate is 'to excel according to international standards of scientific excellence, in the creation of new knowledge and its translation into improved health for Canadians, more effective health services and products and a strengthened Canadian health care system'. Knowledge synthesis is a key element of the knowledge-translation objectives of CIHR, as outlined in our definition of knowledge-translation. PMID:22587985
[Characteristics of Bacillus cereus dissociants].
Doroshenko, E V; Loĭko, N G; Il'inskaia, O N; Kolpakov, A I; Gornova, I B; Klimanova, E V; El'-Registan, G I
2001-01-01
The autoregulation of the phenotypic (populational) variability of the Bacillus cereus strain 504 was studied. The isolated colonial morphotypes of this bacterium were found to differ in their growth characteristics and the synthesis of extracellular proteases. The phenotypic variabilities of vegetative proliferating cells and those germinated from endospores and cystlike refractory cells were different. Bacterial variants also differed in the production of the d1 and d2 factors (the autoinducers of dormancy and autolysis, respectively) and sensitivity to them. The possible role of these factors in the dissociation of microorganisms is discussed.
Ebireri, Jennifer; Aderemi, Adewale V; Omoregbe, Nicholas; Adeloye, Davies
2016-01-01
Background Ischaemic heart disease (IHD) is currently ranked eighth among the leading causes of deaths in sub-Saharan Africa (sSA). Yet, effective population-wide preventive measures targeting risks in the region are still largely unavailable. We aimed to review population-wide and individual-level interventions addressing risk factors of IHD among adults in sSA. Methods A systematic search of MEDLINE, EMBASE, Global Health and AJOL was conducted to identify studies focusing on population-wide and individual-level interventions targeting risks of IHD among adults in sSA. We conducted a detailed synthesis of basic findings of selected studies. Results A total of 2311 studies were identified, with only 9 studies meeting our selection criteria. 3 broad interventions were identified: dietary modifications, physical activity and community-based health promotion measures on tobacco and alcohol cessation. 3 studies reported significant reduction in blood pressure (BP), and another study reported statistically significant reduction in mean total cholesterol. Other outcome measures observed ranged from mild to no reduction in BP, blood glucose, body mass index and total cholesterol, respectively. Conclusions We cannot specify with all certainty contextually feasible interventions that can be effective in modifying IHD risk factors in population groups across sSA. We recommend more research on IHD, particularly on the understanding of the burden, geared towards developing and/or strengthening preventive and treatment interventions for the disease in sSA. PMID:27381212
Schwindt, Adam R.; Winkelman, Dana L.
2016-01-01
Urban freshwater streams in arid climates are wastewater effluent dominated ecosystems particularly impacted by bioactive chemicals including steroid estrogens that disrupt vertebrate reproduction. However, more understanding of the population and ecological consequences of exposure to wastewater effluent is needed. We used empirically derived vital rate estimates from a mesocosm study to develop a stochastic stage-structured population model and evaluated the effect of 17α-ethinylestradiol (EE2), the estrogen in human contraceptive pills, on fathead minnow Pimephales promelas stochastic population growth rate. Tested EE2 concentrations ranged from 3.2 to 10.9 ng L−1 and produced stochastic population growth rates (λ S ) below 1 at the lowest concentration, indicating potential for population decline. Declines in λ S compared to controls were evident in treatments that were lethal to adult males despite statistically insignificant effects on egg production and juvenile recruitment. In fact, results indicated that λ S was most sensitive to the survival of juveniles and female egg production. More broadly, our results document that population model results may differ even when empirically derived estimates of vital rates are similar among experimental treatments, and demonstrate how population models integrate and project the effects of stressors throughout the life cycle. Thus, stochastic population models can more effectively evaluate the ecological consequences of experimentally derived vital rates.
NASA Astrophysics Data System (ADS)
Schinnerer, E.; Colbert, E.; Armus, L.; Scoville, N. Z.; Heckman, T. M.
We obtained sub-arcsecond medium resolution near-infrared spectra of a sample of nearby bright Seyfert galaxies (8 Seyfert 1s, 11 Seyfert 2s) using the KeckII telescope. The stellar absorption lines present in the spectra were used in conjunction with population synthesis models to determine the age of the circumnuclear stellar population. Initial analysis of a sub-sample of the Seyfert galaxies has provided no evidence for a connection between the age of the circumnuclear stellar population and the Seyfert type. The derived ages for the circumnuclear stellar population are in the range of 10 Myr to < 0.5 Gyr assuming an instantaneous starburst (using the STARBURST99 models).
New Editions for the Apple II of the Chelsea Science Simulations.
ERIC Educational Resources Information Center
Pipeline, 1983
1983-01-01
Ten computer simulations for the Apple II are described. Subject areas of programs include: population dynamics, plant competition, enzyme kinetics, evolution and natural selection, genetic mapping, ammonia synthesis, reaction kinetics, wave interference/diffraction, satellite orbits, and particle scattering. (JN)
DOT National Transportation Integrated Search
2013-08-01
"Over the last 50 years, advances in the fields of travel behavior research and travel demand forecasting have been : immense, driven by the increasing costs of infrastructure and spatial limitations in areas of high population density : together wit...
Comparison of stellar population model predictions using optical and infrared spectroscopy
NASA Astrophysics Data System (ADS)
Baldwin, C.; McDermid, R. M.; Kuntschner, H.; Maraston, C.; Conroy, C.
2018-02-01
We present Gemini/GNIRS cross-dispersed near-infrared spectra of 12 nearby early-type galaxies, with the aim of testing commonly used stellar population synthesis models. We select a subset of galaxies from the ATLAS3D sample which span a wide range of ages (single stellar population equivalent ages of 1-15 Gyr) at approximately solar metallicity. We derive star formation histories using four different stellar population synthesis models, namely those of Bruzual & Charlot, Conroy, Gunn & White, Maraston & Strömbäck and Vazdekis et al. We compare star formation histories derived from near-infrared spectra with those derived from optical spectra using the same models. We find that while all models agree in the optical, the derived star formation histories vary dramatically from model to model in the near-infrared. We find that this variation is largely driven by the choice of stellar spectral library, such that models including high-quality spectral libraries provide the best fits to the data, and are the most self-consistent when comparing optically derived properties with near-infrared ones. We also find the impact of age variation in the near-infrared to be subtle, and largely encoded in the shape of the continuum, meaning that the common approach of removing continuum information with a high-order polynomial greatly reduces our ability to constrain ages in the near-infrared.
Nebular Continuum and Line Emission in Stellar Population Synthesis Models
DOE Office of Scientific and Technical Information (OSTI.GOV)
Byler, Nell; Dalcanton, Julianne J.; Conroy, Charlie
Accounting for nebular emission when modeling galaxy spectral energy distributions (SEDs) is important, as both line and continuum emissions can contribute significantly to the total observed flux. In this work, we present a new nebular emission model integrated within the Flexible Stellar Population Synthesis code that computes the line and continuum emission for complex stellar populations using the photoionization code Cloudy. The self-consistent coupling of the nebular emission to the matched ionizing spectrum produces emission line intensities that correctly scale with the stellar population as a function of age and metallicity. This more complete model of galaxy SEDs will improvemore » estimates of global gas properties derived with diagnostic diagrams, star formation rates based on H α , and physical properties derived from broadband photometry. Our models agree well with results from other photoionization models and are able to reproduce observed emission from H ii regions and star-forming galaxies. Our models show improved agreement with the observed H ii regions in the Ne iii/O ii plane and show satisfactory agreement with He ii emission from z = 2 galaxies, when including rotating stellar models. Models including post-asymptotic giant branch stars are able to reproduce line ratios consistent with low-ionization emission regions. The models are integrated into current versions of FSPS and include self-consistent nebular emission predictions for MIST and Padova+Geneva evolutionary tracks.« less
The association between shift work and sick leave: a systematic review
van Drongelen, Alwin; Holte, Kari Anne; Labriola, Merete; Lund, Thomas; van Mechelen, Willem; van der Beek, Allard J
2012-01-01
Shift work is associated with a number of negative health outcomes, although it is not known whether it is associated with sick leave. This systematic review therefore aimed to determine whether an association exists between shift work and sick leave. A systematic literature search was conducted in six databases on observational studies. Two reviewers independently selected relevant articles and appraised methodological quality. Data extraction was performed independently by review couples. Articles were categorised according to shift work characteristics and summarised using a levels of evidence synthesis. In total, the search strategy yielded 1207 references, of which 24 studies met the inclusion criteria. Nine studies were appraised as high quality and used in the levels of evidence synthesis. Two high quality longitudinal studies found a positive association between fixed evening shifts and longer sick leave for female healthcare workers. The evidence was assessed as strong. Evidence was inconclusive for rotating shifts, shift work including nights, for fixed night work, and for 8-hour and 12-hour shifts. The association found between evening work and sick leave in female healthcare workers implies that the association between shift work and sick leave might be schedule and population specific. To study the association further, more high quality studies are necessary that assess and adjust for detailed shift work exposure. PMID:22767871
Curcumin boosts DHA in the brain: implications for the prevention of anxiety disorders
Wu, Aiguo; Noble, Emily E.; Tyagi, Ethika; Ying, Zhe; Zhuang, Yumei; Gomez-Pinilla, Fernando
2015-01-01
Dietary deficiency of docosahexaenoic acid (C22: 6n-3; DHA) is linked to the neuropathology of several cognitive disorders, including anxiety. DHA, which is essential for brain development and protection, is primarily obtained through the diet or synthesized from dietary precursors, however the conversion efficiency is low. Curcumin (diferuloylmethane), which is a principal component of the spice turmeric, complements the action of DHA in the brain, and this study was performed to determine molecular mechanisms involved. We report that curcumin enhances the synthesis of DHA from its precursor, α-linolenic acid (C18: 3n-3; ALA) and elevates levels of enzymes involved in the synthesis of DHA such as FADS2 and elongase 2 in both liver and brain tissue. Furthermore, in vivo treatment with curcumin and ALA reduced anxiety-like behavior in rodents. Taken together, these data suggest that curcumin enhances DHA synthesis, resulting in elevated brain DHA content. These findings have important implications for human health and the prevention of cognitive disease, particularly for populations eating a plant-based diet or who do not consume fish, a primary source of DHA, since DHA is essential for brain function and its deficiency is implicated in many types of neurological disorders. PMID:25550171
Paes, Geísa Pinheiro; Viana, José Marcelo Soriano; Silva, Fabyano Fonseca e; Mundim, Gabriel Borges
2016-01-01
Abstract The objectives of this study were to assess linkage disequilibrium (LD) and selection-induced changes in single nucleotide polymorphism (SNP) frequency, and to perform association mapping in popcorn chromosome regions containing quantitative trait loci (QTLs) for quality traits. Seven tropical and two temperate popcorn populations were genotyped for 96 SNPs chosen in chromosome regions containing QTLs for quality traits. The populations were phenotyped for expansion volume, 100-kernel weight, kernel sphericity, and kernel density. The LD statistics were the difference between the observed and expected haplotype frequencies (D), the proportion of D relative to the expected maximum value in the population, and the square of the correlation between the values of alleles at two loci. Association mapping was based on least squares and Bayesian approaches. In the tropical populations, D-values greater than 0.10 were observed for SNPs separated by 100-150 Mb, while most of the D-values in the temperate populations were less than 0.05. Selection for expansion volume indirectly led to increase in LD values, population differentiation, and significant changes in SNP frequency. Some associations were observed for expansion volume and the other quality traits. The candidate genes are involved with starch, storage protein, lipid, and cell wall polysaccharides synthesis. PMID:27007903
Paes, Geísa Pinheiro; Viana, José Marcelo Soriano; Silva, Fabyano Fonseca E; Mundim, Gabriel Borges
2016-03-01
The objectives of this study were to assess linkage disequilibrium (LD) and selection-induced changes in single nucleotide polymorphism (SNP) frequency, and to perform association mapping in popcorn chromosome regions containing quantitative trait loci (QTLs) for quality traits. Seven tropical and two temperate popcorn populations were genotyped for 96 SNPs chosen in chromosome regions containing QTLs for quality traits. The populations were phenotyped for expansion volume, 100-kernel weight, kernel sphericity, and kernel density. The LD statistics were the difference between the observed and expected haplotype frequencies (D), the proportion of D relative to the expected maximum value in the population, and the square of the correlation between the values of alleles at two loci. Association mapping was based on least squares and Bayesian approaches. In the tropical populations, D-values greater than 0.10 were observed for SNPs separated by 100-150 Mb, while most of the D-values in the temperate populations were less than 0.05. Selection for expansion volume indirectly led to increase in LD values, population differentiation, and significant changes in SNP frequency. Some associations were observed for expansion volume and the other quality traits. The candidate genes are involved with starch, storage protein, lipid, and cell wall polysaccharides synthesis.
Decline of flounder (Platichthys flesus (L.)) at the margin of the species' distribution range
NASA Astrophysics Data System (ADS)
Jokinen, Henri; Wennhage, Håkan; Lappalainen, Antti; Ådjers, Kaj; Rask, Martti; Norkko, Alf
2015-11-01
The Baltic Sea is undergoing large-scale environmental change due to eutrophication, climate change, over-exploitation and habitat destruction, with subsequent degradation of living conditions for many fish species. Signs of this unfavorable development are seen as population declines in species affected. We provide the first synthesis and characterization of the recent population decline in European flounder (Platichthys flesus (L.)) in the northern Baltic Sea, using available fishery-independent data from the Finnish coast, which is at the margin of the distribution range of this species. The objective was to document recent changes in the flounder population, identify the onset and quantify the magnitude of the change. The results showed substantial decreases in flounder numbers and biomass across the whole study area during recent decades. Based on the time series data available, flounder abundances declined by 46-97% from the 1990s to the 2000s, with top values in the mid-1990s and current low levels reached in the early 2000s. Additionally, signs of decreasing flounder size and condition were also observed. We discuss potential reasons for the development in terms of environmental change and fishing, and identify potential bottlenecks for population maintenance and mechanisms behind population change, thereby contributing to our general understanding of marginal flounder populations.
Nikitin, Aleksey G; Potapov, Viktor Y; Brovkina, Olga I; Koksharova, Ekaterina O; Khodyrev, Dmitry S; Philippov, Yury I; Michurova, Marina S; Shamkhalova, Minara S; Vikulova, Olga K; Smetanina, Svetlana A; Suplotova, Lyudmila A; Kononenko, Irina V; Kalashnikov, Viktor Y; Smirnova, Olga M; Mayorov, Alexander Y; Nosikov, Valery V; Averyanov, Alexander V; Shestakova, Marina V
2017-01-01
The association of type 2 diabetes mellitus (T2DM) with the KCNJ11, CDKAL1, SLC30A8, CDKN2B, and FTO genes in the Russian population has not been well studied. In this study, we analysed the population frequencies of polymorphic markers of these genes. The study included 862 patients with T2DM and 443 control subjects of Russian origin. All subjects were genotyped for 10 single nucleotide polymorphisms (SNPs) of the genes using real-time PCR (TaqMan assays). HOMA-IR and HOMA- β were used to measure insulin resistance and β -cell secretory function, respectively. The analysis of the frequency distribution of polymorphic markers for genes KCNJ11, CDKAL1, SLC30A8 and CDKN2B showed statistically significant associations with T2DM in the Russian population. The association between the FTO gene and T2DM was not statistically significant. The polymorphic markers rs5219 of the KCNJ11 gene, rs13266634 of the SLC30A8 gene, rs10811661 of the CDKN2B gene and rs9465871 , rs7756992 and rs10946398 of the CDKAL1 gene showed a significant association with impaired glucose metabolism or impaired β -cell function. In the Russian population, genes, which affect insulin synthesis and secretion in the β -cells of the pancreas, play a central role in the development of T2DM.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clausen, Drew; Wade, Richard A.; Kopparapu, Ravi Kumar
Binaries that contain a hot subdwarf (sdB) star and a main-sequence companion may have interacted in the past. This binary population has historically helped determine our understanding of binary stellar evolution. We have computed a grid of binary population synthesis models using different assumptions about the minimum core mass for helium ignition, the envelope binding energy, the common-envelope ejection efficiency, the amount of mass and angular momentum lost during stable mass transfer, and the criteria for stable mass transfer on the red giant branch and in the Hertzsprung gap. These parameters separately and together can significantly change the entire predictedmore » population of sdBs. Nonetheless, several different parameter sets can reproduce the observed subpopulation of sdB + white dwarf and sdB + M dwarf binaries, which has been used to constrain these parameters in previous studies. The period distribution of sdB + early F dwarf binaries offers a better test of different mass transfer scenarios for stars that fill their Roche lobes on the red giant branch.« less
Woodall, Lucy C; Otero-Ferrer, Francisco; Correia, Miguel; Curtis, Janelle M R; Garrick-Maidment, Neil; Shaw, Paul W; Koldewey, Heather J
2018-01-01
Accurate taxonomy, population demography, and habitat descriptors inform species threat assessments and the design of effective conservation measures. Here we combine published studies with new genetic, morphological and habitat data that were collected from seahorse populations located along the European and North African coastlines to help inform management decisions for European seahorses. This study confirms the presence of only two native seahorse species ( Hippocampus guttulatus and H. hippocampus ) across Europe, with sporadic occurrence of non-native seahorse species in European waters. For the two native species, our findings demonstrate that highly variable morphological characteristics, such as size and presence or number of cirri, are unreliable for distinguishing species. Both species exhibit sex dimorphism with females being significantly larger. Across its range, H. guttulatus were larger and found at higher densities in cooler waters, and individuals in the Black Sea were significantly smaller than in other populations. H. hippocampus were significantly larger in Senegal. Hippocampus guttulatus tends to have higher density populations than H. hippocampus when they occur sympatrically. Although these species are often associated with seagrass beds, data show both species inhabit a wide variety of shallow habitats and use a mixture of holdfasts. We suggest an international mosaic of protected areas focused on multiple habitat types as the first step to successful assessment, monitoring and conservation management of these Data Deficient species.
Whitlock, Raj
2014-01-01
Understanding the effects of intraspecific genetic diversity on the structure and functioning of ecological communities is a fundamentally important part of evolutionary ecology and may also have conservation relevance in identifying the situations in which genetic diversity coincides with species-level diversity.Early studies within this field documented positive relationships between genetic diversity and ecological structure, but recent studies have challenged these findings. Conceptual synthesis has been hampered because studies have used different measures of intraspecific variation (phenotypically adaptive vs. neutral) and have considered different measures of ecological structure in different ecological and spatial contexts. The aim of this study is to strengthen conceptual understanding by providing an empirical synthesis quantifying the relationship between genetic diversity and ecological structure.Here, I present a meta-analysis of the relationship between genetic diversity within plant populations and the structure and functioning of associated ecological communities (including 423 effect sizes from 70 studies). I used Bayesian meta-analyses to examine (i) the strength and direction of this relationship, (ii) the extent to which phenotypically adaptive and neutral (molecular) measures of diversity differ in their association with ecological structure and (iii) variation in outcomes among different measures of ecological structure and in different ecological contexts.Effect sizes measuring the relationship between adaptive diversity (genotypic richness) and both community- and ecosystem-level ecological responses were small, but significantly positive. These associations were supported by genetic effects on species richness and productivity, respectively.There was no overall association between neutral genetic diversity and measures of ecological structure, but a positive correlation was observed under a limited set of demographic conditions. These results suggest that adaptive and neutral genetic diversity should not be treated as ecologically equivalent measures of intraspecific variation.Synthesis. This study advances the debate over whether relationships between genetic diversity and ecological structure are either simply positive or negative, by showing how the strength and direction of these relationships changes with different measures of diversity and in different ecological contexts. The results provide a solid foundation for assessing when and where an expanded synthesis between ecology and genetics will be most fruitful. PMID:25210204
Ecotoxicology of Amphibians and Reptiles
2000-01-01
For many years, ecological research on amphibians and reptiles has lagged behind that of other vertebrates such as fishes, birds, and mammals, despite the known importance of these animals in their environments. The lack of study has been particularly acute in the he area of ecotoxicology where the number of published scientific papers is a fraction of that found for the other vertebrate classes. Recently, scientists have become aware of severe crises among amphibian populations, including unexplained and sudden extinctions, worldwide declines, and hideous malformations. In many of these instances, contaminants have been listed as probable contributors. Data on the effects of contaminants on reptiles are so depauperate that even the most elementary interpretations are difficult. This state-of-the-science review and synthesis of amphibian and reptile ecotoxicology demonstrates the inter-relationships among distribution, ecology, physiology, and contaminant exposure, and interprets these topics as they pertain to comparative toxicity, population declines, malformations, and risk assessment . In this way, the book identifies and serves as a basis for the most pressing research needs in the coming years. The editors have invited 27 other internationally respected experts to examine the state of existing data in specific areas, interpret it in light of current problems, and identify research gaps and needs. Through its emphasis on recent research, extensive reviews and synthesis, Ecotoxicology of Amphibians and Reptiles will remain a definitive reference work well into the new century.
Rates of short-GRB afterglows in association with binary neutron star mergers
NASA Astrophysics Data System (ADS)
Saleem, M.; Pai, Archana; Misra, Kuntal; Resmi, L.; Arun, K. G.
2018-03-01
Assuming all binary neutron star (BNS) mergers produce short gamma-ray bursts, we combine the merger rates of BNS from population synthesis studies, the sensitivities of advanced gravitational wave (GW) interferometer networks, and of the electromagnetic (EM) facilities in various wavebands, to compute the detection rate of associated afterglows in these bands. Using the inclination angle measured from GWs as a proxy for the viewing angle and assuming a uniform distribution of jet opening angle between 3° and 30°, we generate light curves of the counterparts using the open access afterglow hydrodynamics package BOXFIT for X-ray, optical, and radio bands. For different EM detectors, we obtain the fraction of EM counterparts detectable in these three bands by imposing appropriate detection thresholds. In association with BNS mergers detected by five (three) detector networks of advanced GW interferometers, assuming a BNS merger rate of 0.6-774 Gpc-3 yr-1 from population synthesis models, we find the afterglow detection rates (per year) to be 0.04-53 (0.02-27), 0.03-36 (0.01-19), and 0.04-47 (0.02-25) in the X-ray, optical, and radio bands, respectively. Our rates represent maximum possible detections for the given BNS rate since we ignore effects of cadence and field of view in EM follow-up observations.
Picchioni, Dante; Reith, R. Michelle; Nadel, Jeffrey L.; Smith, Carolyn B.
2014-01-01
Sleep is important for neural plasticity, and plasticity underlies sleep-dependent memory consolidation. It is widely appreciated that protein synthesis plays an essential role in neural plasticity. Studies of sleep-dependent memory and sleep-dependent plasticity have begun to examine alterations in these functions in populations with neurological and psychiatric disorders. Such an approach acknowledges that disordered sleep may have functional consequences during wakefulness. Although neurodevelopmental disorders are not considered to be sleep disorders per se, recent data has revealed that sleep abnormalities are among the most prevalent and common symptoms and may contribute to the progression of these disorders. The main goal of this review is to highlight the role of disordered sleep in the pathology of neurodevelopmental disorders and to examine some potential mechanisms by which sleep-dependent plasticity may be altered. We will also briefly attempt to extend the same logic to the other end of the developmental spectrum and describe a potential role of disordered sleep in the pathology of neurodegenerative diseases. We conclude by discussing ongoing studies that might provide a more integrative approach to the study of sleep, plasticity, and neurodevelopmental disorders. PMID:24839550
Mizrahi, Tal; Goldenberg, Shoshana; Heller, Joseph; Arad, Zeev
2016-03-01
Land snails are exposed to conditions of high ambient temperature and low humidity, and their survival depends on a suite of morphological, behavioral, physiological, and molecular adaptations to the specific microhabitat. We tested in six populations of the land snail Theba pisana whether adaptations to different habitats affect their ability to cope with thermal stress and their strategies of heat shock protein (HSP) expression. Levels of Hsp70 and Hsp90 in the foot tissue were measured in field-collected snails and after acclimation to laboratory conditions. Snails were also exposed to various temperatures (32 up to 54 °C) for 2 h and HSP messenger RNA (mRNA) levels were measured in the foot tissue and survival was determined. To test whether the physiological and molecular data are related to genetic parameters, we analyzed T. pisana populations using partial sequences of nuclear and mitochondrial DNA ribosomal RNA genes. We show that populations collected from warmer habitats were more thermotolerant and had higher constitutive levels of Hsp70 isoforms in the foot tissue. Quantitative real-time polymerase chain reaction (PCR) analysis indicated that hsp70 and hsp90 mRNA levels increased significantly in response to thermal stress, although the increase in hsp70 mRNA was larger compared to hsp90 and its induction continued up to higher temperatures. Generally, warm-adapted populations had higher temperatures of maximal induction of hsp70 mRNA synthesis and higher upper thermal limits to HSP mRNA synthesis. Our study suggests that Hsp70 in the foot tissue of T. pisana snails may have important roles in determining stress resistance, while Hsp90 is more likely implicated in signal transduction processes that are activated by stress. In the phylogenetic analysis, T. pisana haplotypes were principally divided into two major clades largely corresponding to the physiological ability to withstand stress, thus pointing to genetically fixed tolerance.
Rastrick, Samuel P. S.; Whiteley, Nia M.
2013-01-01
Although temperature is known to have an important effect on protein synthesis rates and growth in aquatic ectotherms held in the laboratory, little is known about the effects of thermal gradients on natural populations in the field. To address this issue we determined whole-animal fractional rates of protein synthesis (ks) in four dominant species of gammarid amphipods with different distributions along the coasts of Western Europe from arctic to temperate latitudes. Up to three populations of each species were collected in the summer and ks measured within 48 h. Summer ks values were relatively high in the temperate species, Gammarus locusta, from Portugal (48°N) and Wales (53°N) and were maintained across latitudes by the conservation of translational efficiency. In sharp contrast, summer ks remained remarkably low in the boreal/temperate species G. duebeni from Wales, Scotland (58°N) and Tromsø (70°N), probably as a temporary energy saving strategy to ensure survival in rapidly fluctuating environments of the high intertidal. Values for ks increased in acclimated G. duebeni from Scotland and Tromsø showing a lack of compensation with latitude. In the subarctic/boreal species, G. oceanicus, summer ks remained unchanged in Scotland and Tromsø but fell significantly in Svalbard (79°N) at 5°C, despite a slight increase in RNA content. At 79°N, mean ks was 4.5 times higher in the circumpolar species G. setosus than in G. oceanicus due to a doubling in RNA content. The relationship between whole-animal protein synthesis rates and natural thermal gradients is complex, varies between species and appears to be associated with local temperatures and their variability, as well as changes in other environmental factors. PMID:23544122
Ndong Atome, Guy Roger; Ngoua Meye Misso, Rick-Leonid; Sima Obiang, Cédric; Onanga, Richard; Nkogue Mba, Dieudonné
2018-03-08
Gout is caused by a chronic hyperuricemia whose complications are not currently well evaluated in Africa. The aim of this study was to determine the prevalence and risk factors of hyperuricemia and gout in 85 patients recruited. A total of 26 cases of hyperuricemia, i.e., 30.6% of the study population, with 12 cases of gout and seven cases of gouty access. In this population, hyperuricemia was proportional to age ( p -value < 10 -4, OR = 2.6), but it was more prevalent in men, 23.5% versus 7.1% for women ( p -value = 0.0047). In addition, none of these women showed signs of a gouty affection. Consumption of alcohol (OR = 13) and nucleoprotein-rich foods, obesity (BMI 30 kg/m²; OR = 6), family history of gout (OR = 6.8), as well as diseases such as high blood pressure (associated with taking diuretics; OR = 1.7), renal insufficiency (OR = 4.4) and diabetes ( p < 0.049) were the main factors of the diseases associated with gout and hyperuricemia in this population. The biochemical role of these factors may increase and/or decrease the processes of synthesis and/or elimination of uric acid by acting on metabolites involved in the regulation of urate production.
Ndong Atome, Guy Roger; Ngoua Meye Misso, Rick-Leonid; Sima Obiang, Cédric; Onanga, Richard; Nkogue Mba, Dieudonné
2018-01-01
Gout is caused by a chronic hyperuricemia whose complications are not currently well evaluated in Africa. The aim of this study was to determine the prevalence and risk factors of hyperuricemia and gout in 85 patients recruited. A total of 26 cases of hyperuricemia, i.e., 30.6% of the study population, with 12 cases of gout and seven cases of gouty access. In this population, hyperuricemia was proportional to age (p-value < 10−4, OR = 2.6), but it was more prevalent in men, 23.5% versus 7.1% for women (p-value = 0.0047). In addition, none of these women showed signs of a gouty affection. Consumption of alcohol (OR = 13) and nucleoprotein-rich foods, obesity (BMI 30 kg/m2; OR = 6), family history of gout (OR = 6.8), as well as diseases such as high blood pressure (associated with taking diuretics; OR = 1.7), renal insufficiency (OR = 4.4) and diabetes (p < 0.049) were the main factors of the diseases associated with gout and hyperuricemia in this population. The biochemical role of these factors may increase and/or decrease the processes of synthesis and/or elimination of uric acid by acting on metabolites involved in the regulation of urate production. PMID:29518007
[Folates and fetal programming: role of epigenetics and epigenomics].
Guéant, Jean-Louis; Daval, Jean-Luc; Vert, Paul; Nicolas, Jean-Pierre
2012-12-01
Folates are needed for synthesis of methionine, the precursor of S-adenosyl methionine (SAM). They play therefore a key role in nutrition and epigenomics by fluxing monocarbons towards synthesis or methylation of DNA and RNA, and methylation of gene transregulators, respectively. The deficiency produces intrauterine growth retardation and birth dejects. Folate deficiency deregulates epigenomic mechanisms related to fetal programming through decreased cellular availability of SAM. Epigenetic mechanisms of folate deficiency are illustrated by inheritance of coat colour of agouti mice model and altered expression of Igf2/H19 imprinting genes. Dietary exposure to fumonisin FB1 acts synergistically with folate deficiency on alterations of heterochromatin assembly. Deficiency in folate and vitamin B12 produces impaired fatty acid oxidation in liver and heart through imbalanced methylation and acetylation of PGC1-alpha and decreased expression of SIRT1, and long-lasting cognitive disabilities through impaired hippocampal cell proliferation, differentiation and plasticity and atrophy of hippocampal CA1. Deciphering these mechanisms will help understand the discordances between experimental models and population studies on folate supplementation.
Realistic Data-Driven Traffic Flow Animation Using Texture Synthesis.
Chao, Qianwen; Deng, Zhigang; Ren, Jiaping; Ye, Qianqian; Jin, Xiaogang
2018-02-01
We present a novel data-driven approach to populate virtual road networks with realistic traffic flows. Specifically, given a limited set of vehicle trajectories as the input samples, our approach first synthesizes a large set of vehicle trajectories. By taking the spatio-temporal information of traffic flows as a 2D texture, the generation of new traffic flows can be formulated as a texture synthesis process, which is solved by minimizing a newly developed traffic texture energy. The synthesized output captures the spatio-temporal dynamics of the input traffic flows, and the vehicle interactions in it strictly follow traffic rules. After that, we position the synthesized vehicle trajectory data to virtual road networks using a cage-based registration scheme, where a few traffic-specific constraints are enforced to maintain each vehicle's original spatial location and synchronize its motion in concert with its neighboring vehicles. Our approach is intuitive to control and scalable to the complexity of virtual road networks. We validated our approach through many experiments and paired comparison user studies.
[Effect of starvation on blood protein levels in the population of Dobrinja (1992-1995)].
Hasković, E
2000-01-01
In nutritional protein deficiency, numerous studies verified utilization of amino acids generated from tissue degradation in intensive protein synthesis. Unlike liver, muscle protein synthesis is extremely dependent on external supplies of essential amino acids. Prolonged nutritional protein deficiency results in decrease of body weight as well as total protein concentration, in particular in early days of starvation. In prolonged starvation during the war, significant decrease of body weight was registered in 70 subjects while their total protein concentration remained within the expected range and did not significantly differ the values recorded in the control group. Concentration of serum albumines in the control group was lower than the concentration recorded in the tested group, while the serum globulins concentration was higher in the control group. Although the difference in body weight between the tested and the control group was statistically significant, no significant difference in the concentration of total proteins, albumines and globulines was recorded.
Microwave-Assisted Synthesis of Bio-Active Heterocycles and Fine Chemicals in Aqueous Media
Human health, especially in the aging population, mostly depends on various medicines, and researchers are combating against emerging diseases by new drug discovery. Heterocyclic compounds hold a special place among pharmaceutically active natural products as well as synthetic co...
USDA-ARS?s Scientific Manuscript database
Molt frequency of workers in laboratory-reared juvenile colonies and foraging population from field colonies of Coptotermes formosanus Shiraki was determined using planar arenas in laboratory. Given that, chitin synthesis inhibitor (CSI)-incorporated baits disrupt the molting process of workers that...
Nitta, T; Konno-Ejiri, H; Nemoto, K; Okumura, S; Ozawa, A; Nakano, M
1986-09-01
Butanol-extracted water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii was mitogenic to murine splenic B lymphocytes, but not T lymphocytes. When murine splenic cells were cultured in the presence of Bu-WSA and concanavalin A (Con A) together, [3H]thymidine uptake of the culture cells synergically increased. The mechanism of the synergy of Con A and Bu-WSA and the participation of interleukin (IL) 1 and 2 in the synergy were studied. The proliferation cells in the synergy were Lyt-1+23- lymphocytes. Ia-positive accessory cells were required for the response. When separated cell populations and Marbrook-type culture vessels were used, a mixed cell population of T lymphocytes and B lymphocytes or macrophages (M phi) produced some active factor(s) after co-stimulation by Con A and Bu-WSA, and the factors enhanced DNA synthesis of another Con A-activated T lymphocyte population. Supernatants obtained from the spleen cell cultures or the mixed cell cultures with T lymphocytes and M phi in the presence of Con A and Bu-WSA contained greater amounts of IL-1 and IL-2 than those from cultures containing Con A or Bu-WSA alone. An addition of exogenous IL-1 or IL-2 to spleen cell cultures with Con A resulted in a proliferative response like that obtained through co-stimulation by Con A and Bu-WSA. These results suggest that the synergistic effect of Con A and Bu-WSA on the proliferative response in murine splenic cells is sustained by the enhancement of production of these T-lymphocyte growth factors.
The distribution of new HIV infections by mode of exposure in Morocco
Mumtaz, Ghina R; Kouyoumjian, Silva P; Hilmi, Nahla; Zidouh, Ahmed; Rhilani, Houssine El; Alami, Kamal; Bennani, Aziza; Gouws, Eleanor; Ghys, Peter Denis; Abu-Raddad, Laith J
2013-01-01
Objectives Building on a wealth of new empirical data, the objective of this study was to estimate the distribution of new HIV infections in Morocco by mode of exposure using the modes of transmission (MoT) mathematical model. Methods The MoT model was implemented within a collaboration with the Morocco Ministry of Health and the Joint United Nations Programme on HIV/AIDS. The model was parameterised through a comprehensive review and synthesis of HIV and risk behaviour data in Morocco, mainly through the Middle East and North Africa HIV/AIDS Synthesis Project. Uncertainty analyses were used to assess the reliability of and uncertainty around our calculated estimates. Results Female sex workers (FSWs), clients of FSWs, men who have sex with men (MSM) and injecting drug users (IDUs) contributed 14%, 24%, 14% and 7% of new HIV infections, respectively. Two-thirds (67%) of new HIV infections occurred among FSWs, clients of FSWs, MSM and IDUs, or among the stable sexual partners of these populations. Casual heterosexual sex contributed 7% of HIV infections. More than half (52%) of HIV incidence is among females, but 71% of these infections are due to an infected spouse. The vast majority of HIV infections among men (89%) are due to high-risk behaviour. A very small HIV incidence is predicted to arise from medical injections or blood transfusions (0.1%). Conclusions The HIV epidemic in Morocco is driven by HIV incidence in high-risk population groups, with commercial heterosexual sex being the largest contributor to incidence. There is a need to focus HIV response more on these populations, mainly through proactive and sustainable HIV surveillance, and the expansion and increased geographical coverage of services such as condom promotion among FSWs, voluntary counselling and testing, harm reduction and treatment. PMID:23413401
Effects of sound exposure on the growth and intracellular macromolecular synthesis of E. coli k-12
Zhang, Yongzhu; Wu, Ying
2016-01-01
Microbes, as one of the primary producers of the biosphere, play an important role in ecosystems. Exploring the mechanism of adaptation and resistance of microbial population to various environmental factors has come into focus in the fields of modern microbial ecology and molecular ecology. However, facing the increasingly serious problem of acoustic pollution, very few efforts have been put forth into studying the relation of single cell organisms and sound field exposure. Herein, we studied the biological effects of sound exposure on the growth of E. coli K-12 with different acoustic parameters. The effects of sound exposure on the intracellular macromolecular synthesis and cellular morphology of E. coli K-12 were also analyzed and discussed. Experimental results indicated that E. coli K-12 exposed to sound waves owned a higher biomass and a faster specific growth rate compared to the control group. Also, the average length of E. coli K-12 cells increased more than 27.26%. The maximum biomass and maximum specific growth rate of the stimulation group by 8000 Hz, 80dB sound wave was about 1.7 times and 2.5 times that of the control group, respectively. Moreover, it was observed that E. coli K-12 can respond rapidly to sound stress at both the transcriptional and posttranscriptional levels by promoting the synthesis of intracellular RNA and total protein. Some potential mechanisms may be involved in the responses of bacterial cells to sound stress. PMID:27077011
Effects of sound exposure on the growth and intracellular macromolecular synthesis of E. coli k-12.
Gu, Shaobin; Zhang, Yongzhu; Wu, Ying
2016-01-01
Microbes, as one of the primary producers of the biosphere, play an important role in ecosystems. Exploring the mechanism of adaptation and resistance of microbial population to various environmental factors has come into focus in the fields of modern microbial ecology and molecular ecology. However, facing the increasingly serious problem of acoustic pollution, very few efforts have been put forth into studying the relation of single cell organisms and sound field exposure. Herein, we studied the biological effects of sound exposure on the growth of E. coli K-12 with different acoustic parameters. The effects of sound exposure on the intracellular macromolecular synthesis and cellular morphology of E. coli K-12 were also analyzed and discussed. Experimental results indicated that E. coli K-12 exposed to sound waves owned a higher biomass and a faster specific growth rate compared to the control group. Also, the average length of E. coli K-12 cells increased more than 27.26%. The maximum biomass and maximum specific growth rate of the stimulation group by 8000 Hz, 80dB sound wave was about 1.7 times and 2.5 times that of the control group, respectively. Moreover, it was observed that E. coli K-12 can respond rapidly to sound stress at both the transcriptional and posttranscriptional levels by promoting the synthesis of intracellular RNA and total protein. Some potential mechanisms may be involved in the responses of bacterial cells to sound stress.
The big data potential of epidemiological studies for criminology and forensics.
DeLisi, Matt
2018-07-01
Big data, the analysis of original datasets with large samples ranging from ∼30,000 to one million participants to mine unexplored data, has been under-utilized in criminology. However, there have been recent calls for greater synthesis between epidemiology and criminology and a small number of scholars have utilized epidemiological studies that were designed to measure alcohol and substance use to harvest behavioral and psychiatric measures that relate to the study of crime. These studies have been helpful in producing knowledge about the most serious, violent, and chronic offenders, but applications to more pathological forensic populations is lagging. Unfortunately, big data relating to crime and justice are restricted and limited to criminal justice purposes and not easily available to the research community. Thus, the study of criminal and forensic populations is limited in terms of data volume, velocity, and variety. Additional forays into epidemiology, increased use of available online judicial and correctional data, and unknown new frontiers are needed to bring criminology up to speed in the big data arena. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
Genetic Factors That Might Lead to Different Responses in Individuals Exposed to Perchlorate
Scinicariello, Franco; Murray, H. Edward; Smith, Lester; Wilbur, Sharon; Fowler, Bruce A.
2005-01-01
Perchlorate has been detected in groundwater in many parts of the United States, and recent detection in vegetable and dairy food products indicates that contamination by perchlorate is more widespread than previously thought. Perchlorate is a competitive inhibitor of the sodium iodide symporter, the thyroid cell–surface protein responsible for transporting iodide from the plasma into the thyroid. An estimated 4.3% of the U.S. population is subclinically hypothyroid, and 6.9% of pregnant women may have low iodine intake. Congenital hypothyroidism affects 1 in 3,000 to 1 in 4,000 infants, and 15% of these cases have been attributed to genetic defects. Our objective in this review is to identify genetic biomarkers that would help define subpopulations sensitive to environmental perchlorate exposure. We review the literature to identify genetic defects involved in the iodination process of the thyroid hormone synthesis, particularly defects in iodide transport from circulation into the thyroid cell, defects in iodide transport from the thyroid cell to the follicular lumen (Pendred syndrome), and defects of iodide organification. Furthermore, we summarize relevant studies of perchlorate in humans. Because of perchlorate inhibition of iodide uptake, it is biologically plausible that chronic ingestion of perchlorate through contaminated sources may cause some degree of iodine discharge in populations that are genetically susceptible to defects in the iodination process of the thyroid hormone synthesis, thus deteriorating their conditions. We conclude that future studies linking human disease and environmental perchlorate exposure should consider the genetic makeup of the participants, actual perchlorate exposure levels, and individual iodine intake/excretion levels. PMID:16263499
Review of behaviour change interventions to reduce population salt intake.
Trieu, Kathy; McMahon, Emma; Santos, Joseph Alvin; Bauman, Adrian; Jolly, Kellie-Ann; Bolam, Bruce; Webster, Jacqui
2017-02-08
Excess salt intake is a major cause of raised blood pressure-the leading risk factor for death and disability worldwide. Although behaviour change interventions such as awareness campaigns and health education programs are implemented to reduce salt intake, their effectiveness is unclear. This global systematic review investigates the impact of population-level behaviour change interventions that aim to reduce salt intake. A search for published and grey literature was conducted using PubMed, Cochrane Library, Embase, Web of Science, Sage, Scopus, OpenGrey, Google Scholar and other relevant organizations' websites. Studies were included if 1) published between 2005 and 2015; 2) the education or awareness-raising interventions were aimed at the population or sub-population and 3) salt intake and/or salt-related behaviours were outcome measures. Study and intervention characteristics were extracted for the descriptive synthesis and study quality was assessed. Twenty two studies involving 41,448 participants were included. Most were conducted in high income countries (n = 16), targeting adults (n = 21) in the general population (n = 16). Behaviour change interventions were categorised as health education interventions (n = 14), public awareness campaigns (n = 4) and multi-component interventions (including both health education and awareness campaigns, n = 4). 19 of the 22 studies demonstrated significant reductions in estimated salt intake and/or improvement in salt-related behaviours. All studies showed high risk of bias in one or more domains. Of the 10 higher quality studies, 5 found a significant effect on salt intake or salt behaviours based on the more objective outcome assessment method. Based on moderate quality of evidence, population-level behaviour change interventions can improve salt-related behaviours and/or reduce salt intake. However, closer analysis of higher quality studies show inconsistent evidence of the effectiveness and limited effect sizes suggest the implementation of education and awareness-raising interventions alone are unlikely to be adequate in reducing population salt intake to the recommended levels. A framework which guides rigorous research and evaluation of population-level interventions in real-world settings would help understand and support more effective implementation of interventions to reduce salt intake.
Efficient gene transfer into nondividing cells by adeno-associated virus-based vectors.
Podsakoff, G; Wong, K K; Chatterjee, S
1994-01-01
Gene transfer vectors based on adeno-associated virus (AAV) are emerging as highly promising for use in human gene therapy by virtue of their characteristics of wide host range, high transduction efficiencies, and lack of cytopathogenicity. To better define the biology of AAV-mediated gene transfer, we tested the ability of an AAV vector to efficiently introduce transgenes into nonproliferating cell populations. Cells were induced into a nonproliferative state by treatment with the DNA synthesis inhibitors fluorodeoxyuridine and aphidicolin or by contact inhibition induced by confluence and serum starvation. Cells in logarithmic growth or DNA synthesis arrest were transduced with vCWR:beta gal, an AAV-based vector encoding beta-galactosidase under Rous sarcoma virus long terminal repeat promoter control. Under each condition tested, vCWR:beta Gal expression in nondividing cells was at least equivalent to that in actively proliferating cells, suggesting that mechanisms for virus attachment, nuclear transport, virion uncoating, and perhaps some limited second-strand synthesis of AAV vectors were present in nondividing cells. Southern hybridization analysis of vector sequences from cells transduced while in DNA synthetic arrest and expanded after release of the block confirmed ultimate integration of the vector genome into cellular chromosomal DNA. These findings may provide the basis for the use of AAV-based vectors for gene transfer into quiescent cell populations such as totipotent hematopoietic stem cells. Images PMID:8057446
Efficient gene transfer into nondividing cells by adeno-associated virus-based vectors.
Podsakoff, G; Wong, K K; Chatterjee, S
1994-09-01
Gene transfer vectors based on adeno-associated virus (AAV) are emerging as highly promising for use in human gene therapy by virtue of their characteristics of wide host range, high transduction efficiencies, and lack of cytopathogenicity. To better define the biology of AAV-mediated gene transfer, we tested the ability of an AAV vector to efficiently introduce transgenes into nonproliferating cell populations. Cells were induced into a nonproliferative state by treatment with the DNA synthesis inhibitors fluorodeoxyuridine and aphidicolin or by contact inhibition induced by confluence and serum starvation. Cells in logarithmic growth or DNA synthesis arrest were transduced with vCWR:beta gal, an AAV-based vector encoding beta-galactosidase under Rous sarcoma virus long terminal repeat promoter control. Under each condition tested, vCWR:beta Gal expression in nondividing cells was at least equivalent to that in actively proliferating cells, suggesting that mechanisms for virus attachment, nuclear transport, virion uncoating, and perhaps some limited second-strand synthesis of AAV vectors were present in nondividing cells. Southern hybridization analysis of vector sequences from cells transduced while in DNA synthetic arrest and expanded after release of the block confirmed ultimate integration of the vector genome into cellular chromosomal DNA. These findings may provide the basis for the use of AAV-based vectors for gene transfer into quiescent cell populations such as totipotent hematopoietic stem cells.
Menendez-Miranda, Mario; Fernandez-Arguelles, Maria T; Costa-Fernandez, Jose M; Encinar, Jorge Ruiz; Sanz-Medel, Alfredo
2014-08-11
Separation and identification of nanoparticles of different composition, with similar particle diameter, coexisting in heterogeneous suspensions of polymer-coated CdSe/ZnS quantum dots (QDs) have been thoroughly assessed by asymmetric flow field-flow fractionation (AF4) coupled on-line to fluorescence and inductively coupled plasma mass spectrometry (ICPMS) detectors. Chemical characterization of any previously on-line separated nanosized species was achieved by the measurement of the elemental molar ratios of every element involved in the synthesis of the QDs, using inorganic standards and external calibration by flow injection analysis (FIA). Such elemental molar ratios, strongly limited so far to pure single nanoparticles suspensions, have been achieved with adequate accuracy by coupling for the first time an ICP-QQQ instrument to an AF4 system. This hyphenation turned out to be instrumental to assess the chemical composition of the different populations of nanoparticles coexisting in the relatively complex mixtures, due to its capabilities to detect the hardly detectable elements involved in the synthesis. Interestingly such information, complementary to that obtained by fluorescence, was very valuable to detect and identify unexpected nanosized species, present at significant level, produced during QDs synthesis and hardly detectable by standard approaches. Copyright © 2014. Published by Elsevier B.V.
Energy and resource basis of an Italian coastal resort region integrated using emergy synthesis.
Vassallo, Paolo; Paoli, Chiara; Tilley, David R; Fabiano, Mauro
2009-10-01
Sustainable development of coastal zones must balance economic development that encourages human visitation from a larger population with desires that differ from the local residents with the need to maintain opportunities for the local resident society and conserve ecological capital, which may serve as the basis for residents. We present a case study in which the sustainability level of a coastal zone (Riviera del Beigua), located along the Ligurian coast of north-western Italy, was assessed through the lens of systems ecology using emergy synthesis to integrate across economic, social and environmental sub-systems. Our purposes were (1) to quantify the environmental sustainability level of this coastal zone, (2) to evaluate the role of tourism in affecting the economy, society and environment, and (3) to compare emergy synthesis to Butler's Tourism Area Life Cycle model (TALC). Results showed that 81% of the total emergy consumption in the coastal zone was derived from external sources, indicating that this tourist-heavy community was not sustainable. Tourism, as the dominant economic sub-system, consumed 42% of the total emergy budget, while local residents used the remaining 58%. The progressive stages of the TALC model were found to parallel the dynamic changes in the ratio of external emergy inputs to local emergy inputs, suggesting that emergy synthesis could be a useful tool for detecting a tourist region's TALC stage. Use of such a quantitative tool could expedite sustainability assessment to allow administrative managers to understand the complex relationship between a region's economy, environment and resident society so sound policies can be developed to improve overall sustainability.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peacock, Mark B.; Zepf, Stephen E.; Maccarone, Thomas J.
2011-08-10
Accurate stellar population synthesis models are vital in understanding the properties and formation histories of galaxies. In order to calibrate and test the reliability of these models, they are often compared with observations of star clusters. However, relatively little work has compared these models in the ugriz filters, despite the recent widespread use of this filter set. In this paper, we compare the integrated colors of globular clusters in the Sloan Digital Sky Survey (SDSS) with those predicted from commonly used simple stellar population (SSP) models. The colors are based on SDSS observations of M31's clusters and provide the largestmore » population of star clusters with accurate photometry available from the survey. As such, it is a unique sample with which to compare SSP models with SDSS observations. From this work, we identify a significant offset between the SSP models and the clusters' g - r colors, with the models predicting colors which are too red by g - r {approx} 0.1. This finding is consistent with previous observations of luminous red galaxies in the SDSS, which show a similar discrepancy. The identification of this offset in globular clusters suggests that it is very unlikely to be due to a minority population of young stars. The recently updated SSP model of Maraston and Stroembaeck better represents the observed g - r colors. This model is based on the empirical MILES stellar library, rather than theoretical libraries, suggesting an explanation for the g - r discrepancy.« less
Baila-Rueda, L; Cenarro, A; Lamiquiz-Moneo, I; Mateo-Gallego, R; Bea, A M; Perez-Calahorra, S; Marco-Benedi, V; Civeira, F
2017-05-01
Some oxysterols are precursors of bile acid synthesis and play an important role in cholesterol homeostasis. However, if they are involved in the pathogeny of genetic hypercholesterolemia has not been previously explored. We have studied non-cholesterol sterol markers of cholesterol synthesis (lanosterol and desmosterol) and oxysterols (7α-hydroxy-4-cholesten-3-one, 24S-hydroxycholesterol and 27-hydroxycholesterol) in 200 affected subjects with primary hypercholesterolemia of genetic origin, negative for mutations in LDLR, APOB, PCSK9 and APOE genes (non-FH GH) and 100 normolipemic controls. All studied oxysterols and cholesterol synthesis markers were significantly higher in affected subjects than controls (P<0.001). Ratios of oxysterols to total cholesterol were higher in non-FH GH than in controls, although only 24S-hydroxycholesterol showed statistical significance (P<0.001). Cholesterol synthesis markers had a positive correlation with BMI, triglycerides, cholesterol and apoB in control population. However, these correlations disappeared in non-FH GH with the exception of a weak positive correlation for non-HDL cholesterol and apoB. The same pattern was observed for oxysterols with high positive correlation in controls and absence of correlation for non-FH GH, except non-HDL cholesterol for 24S-hydroxycholesterol and 27-hydroxycholesterol and apoB for 27-hydroxycholesterol. All non-cholesterol sterols had positive correlation among them in patients and in controls. A total of 65 (32.5%) and 35 (17.5%) affected subjects presented values of oxysterols ratios to total cholesterol above the 95th percentile of the normal distribution (24S-hydroxycholesterol and 27-hydroxycholesterol, respectively). Those patients with the highest levels of 24S-hydroxycholesterol associated an increase in the carotid intima media thickness. These results suggest that bile acid metabolism is affected in some patients with primary hypercholesterolemia of genetic origin, negative for mutations in the candidate genes, and may confer a higher cardiovascular risk. Our results confirm that cholesterol synthesis overproduction is a primary defect in non-HF GH and suggest that subjects with non-FH GH show high levels of oxysterols in response to hepatic overproduction of cholesterol. Copyright © 2016 Elsevier Ltd. All rights reserved.
The influence of predation on the chronic response of Artemia sp. populations to a toxicant
BEKETOV, MIKHAIL A; LIESS, MATTHIAS
2006-01-01
Environmental risk assessment of contaminants is conventionally based on toxic effects assessed in organism-level test systems. We suggest that, for the prediction of toxicant effects, population- and community-level effects should be considered. The aim of this study was to investigate how predation could alter a prey population's response to a toxicant to reveal effects at population and community levels.Populations of the brine shrimp Artemia sp. were maintained in the laboratory with and without simulated predation. Individuals were exposed for 1 h to the pyrethroid insecticide esfenvalerate (0, 0·01, 0·04 and 0·08 µg L−1) and subsequently observed for 6 weeks.Unpredated exposed populations showed a reduced population density compared with the control. However, even at the highest concentration of insecticide, populations were sustained until the end of the experiment. The lower density in the exposed populations led to reduced competition and subsequently to enhanced development of surviving individuals and an increased proportion of young individuals. In contrast, the combination of predation and short-term toxicant exposure at concentrations of 0·04 and 0·08 µg L−1 produced extinction of the populations after 39 and 32 days of exposure, respectively.Synthesis and applications. The response of populations of brine shrimp to toxicants at the community level may be stronger when predation is present than the response of populations without predation pressure, as the regulation capacity of the population (measured as an increased production of offspring at reduced population densities) is exhausted when predation is present. Future ecotoxicological risk assessment schemes should consider relevant community characteristics such as predation as part of an environmental risk assessment. PMID:18784796
Gender differences in socioeconomic inequality in mortality.
Mustard, C A; Etches, J
2003-12-01
There is uncertainty about whether position in a socioeconomic hierarchy confers different mortality risks on men and women. The objective of this study was to conduct a systematic review of gender differences in socioeconomic inequality in risk of death. This research systematically reviewed observational cohort studies describing all cause or cause specific mortality for populations aged 25-64 in developed countries. For inclusion in the review, mortality had to be reported stratified by gender and by one or more measures of socioeconomic status. For all eligible studies, five absolute and six relative measures of the socioeconomic inequality in mortality were computed for male and female populations separately. A total of 136 published papers were reviewed for eligibility, with 58 studies deemed eligible for inclusion. Of these eligible studies, 20 papers published data that permitted the computation of both absolute and relative measures of inequality. Absolute measures of socioeconomic mortality inequality for men and women generally agreed, with about 90% of studies indicating that male mortality was more unequal than female mortality across socioeconomic groups. In contrast, the pattern of relative inequality results across the 20 studies suggested that male and female socioeconomic inequality in mortality was equivalent. Inferences about gender differences in socioeconomic inequality in mortality are sensitive to the choice of inequality measure. Wider understanding of this methodological issue would improve the clarity of the reporting and synthesis of evidence on the magnitude of health inequalities in populations.
Viability of porcine nasal septal cartilage grafts following Nd:YAG (n=1.32μm) laser radiation
NASA Astrophysics Data System (ADS)
Chao, Kenneth K. H.; Wong, Brian J.; Kim, Hong K.; Milner, Thomas E.; Sung, Chung-Ho; Sobol, Emil N.; Nelson, J. Stuart
2000-06-01
Mechanically deformed morphologic cartilage grafts undergo a temperature dependent phase transformation during sustained laser irradiation that results in reshaping of the specimen. While thermal, optical, and mechanical properties of cartilage undergoing laser heating have been previously investigated, the viability of these irradiated grafts has yet to be examined closely until now. In this study, chondrocyte viability following laser irradiation was determined by measuring the incorporation of radiolabelled sulfate (Na 35SO4-2) into proteoglycan (PTG) macromolecules. Proteoglycans are highly sulfated and are the principal molecular constituents of cartilage matrix. Their synthesis directly reflects chondrocyte viability. By measuring the scintillation counts of 35SO4-2 uptake and normalizing the value by the total protein content of each specimen we can determine the level of PTG synthesis rates following laser reshaping. Regional baseline PTG synthesis rates as a function of location was determined by dividing each specimen into six regions. All regions except the most cephalic are demonstrated similar PTG synthesis rates. The most cephalic region exhibited a significantly greater PTG synthesis rates. In order to establish a positive control for this study, specimens were immersed in boiling saline water for approximately 40 minutes. The boiled specimens demonstrated a fivefold increase in normalized radioisotope uptake and suggest that the non-specific uptake of radioactive Na35SO4-2 is caused by structural alterations in the collagen matrix caused by extensive thermal exposure. To avoid this thermal artifact, another positive control was established using nitric oxide was to induce apoptosis of the chondrocytes, resulting in significantly lower PTG synthesis compared to untreated tissue. Cartilage specimens (25 X 10 X 2 mm) were irradiated with light emitted from an Nd:YAG laser (25 W/cm2, (lambda) equals 1.32 micrometer) while radiometric surface temperature, internal stress, and backscattered light were simultaneously recorded. Individual specimens underwent either one, two, or three sequential laser exposures with the duration of each exposure determined in real-time from observation of characteristic changes in integrated backscattered light intensity that correlate with thermal mediated stress relaxation. A five-minute time interval between each irradiation was given to allow the cartilage to return to thermal equilibrium. Average laser exposure for each irradiation sequence was recorded (5, 8.3, 12.2 sec). PTG synthesis decreased with increasing laser exposure, but was noted to remain above baseline levels for NO treated tissue. To further refine these results and minimize the effect of regional tissue variations, 7 mm diameter discs excised from the most cephalic portions and a middle region of the pig nasal septal cartilages were irradiated. A reduction of PTG synthesis rates was noted with each successive irradiation, suggesting that laser mediated cartilage reshaping acutely does not eliminate the population of viable chondrocytes. The degree of reduction in PTG synthesis is dependent upon the time-temperature dependent heating profile created during laser irradiation, and carefully monitored dosimetry is necessary to ensure chondrocyte viability.
Daker-White, Gavin; Donovan, Jenny; Campbell, Rona
2014-01-01
To synthesize published qualitative studies concerning the lived experience of rheumatoid arthritis (RA). To compare the conceptual features of qualitative studies covering two different time periods. In 2002, 24 items published 1975-2001 were identified in comprehensive literature searches and assessed by multiple reviewers. In 2010, the first author found 28 articles published 2002-2009 in a simple search of the Medline database and synthesized them alone. Articles were synthesized using meta-ethnography. Both syntheses found that the main symptoms of RA are variable and unpredictable. However, in the first synthesis a sociological model dominated where RA was seen as an assault on self-identity with devastating social consequences. The main concepts were biographical disruption, role incompetence and the dread of dependency on others. In the second synthesis, the findings produced a model for health care practitioners tied to perceptions of control and incorporating a career-adaptation model of the experience of RA. We recommend that future synthesizers and primary qualitative health researchers focus more on non-hospital based populations and non-English language articles or study participants. The implications for rehabilitation follow from reflecting the findings of the synthesis against existing psychological models of coping and adaptation in RA. Implications for Rehabilitation Coping and adaptation are biographical processes, although the relative importance of active "disease mastery" versus more passive "getting used to it" is unclear. The uncertainty and fluctuating nature of symptoms and disease course presents existential challenges for people with RA in relation to maintaining physical functioning and social roles. Within a social model of disability, these findings point to potential intervention sites in society and relationships that would benefit people living with RA.
ERIC Educational Resources Information Center
Edwards, Paul
The paper examines the applications of microcomputers to recreation programing for blind persons. The accessibility of microcomputers to this population is discussed, and the advantages as well as disadvantages of speech synthesis equipment are noted. Information is presented on the modification of hardware for Radio Shack and Apple computers.…
Stellar Populations in Elliptical Galaxies
NASA Astrophysics Data System (ADS)
Angeletti, Lucio; Giannone, Pietro
The R1/n law for the radial surface brightness of elliptical galaxies and the "Best Accretion Model" together with the "Concentration Model" have been combined in order to determine the mass and dynamical structure of largely-populated star systems. Families of models depending on four parameters have been used to fit the observed surface radial profiles of some spectro-photometric indices of a sample of eleven galaxies. We present the best agreements of the spectral index Mg2 with observations for three selected galaxies representative of the full sample. For them we have also computed the spatial distributions of the metal abundances, which are essential to achieve a population synthesis.
A frequency standard via spectrum analysis and direct digital synthesis
NASA Astrophysics Data System (ADS)
Li, Dawei; Shi, Daiting; Hu, Ermeng; Wang, Yigen; Tian, Lu; Zhao, Jianye; Wang, Zhong
2014-11-01
We demonstrated a frequency standard based on a detuned coherent population beating phenomenon. In this phenomenon, the beat frequency of the radio frequency for laser modulation and the hyperfine splitting can be obtained by digital signal processing technology. After analyzing the spectrum of the beat frequency, the fluctuation information is obtained and applied to compensate for the frequency shift to generate the standard frequency by the digital synthesis method. Frequency instability of 2.6 × 1012 at 1000 s is observed in our preliminary experiment. By eliminating the phase-locking loop, the method will enable us to achieve a full-digital frequency standard with remarkable stability.
Ator, Scott W.; Blazer, Vicki S.; Brakebill, John W.; Cahoon, Donald R.; Claggett, Peter; Cronin, Thomas M.; Denver, Judith M.; Densmore, Christine L.; Gellis, Allen C.; Hupp, Cliff R.; Landwehr, Jurate M.; Langland, Michael J.; Ottinger, Christopher A.; Pavich, Milan J.; Perry, Matthew C.; Phillips, Scott W.; Preston, Stephen D.; Raffensperger, Jeff P.; Rattner, Barnett A.; Rybicki, Nancy B.; Willard, Debra A.; Phillips, Scott W.
2007-01-01
The purpose of this report is to present a synthesis of the USGS Chesapeake Bay science related to the 2001-06 goals and provide implications for environmental management. The report provides USGS findings that address the science needs of the Chesapeake Bay Program (CBP) restoration goals and includes summaries of 1. land-use change; 2. water quality in the watershed, including nutrients, sediment, and contaminants; 3. long-term changes in climate and estuarine water quality; 4. estuary habitats, focusing on submerged aquatic vegetation (SAV) and tidal wetlands; and 5. factors affecting fish and waterbird populations.
de Graaff, Barbara; Neil, Amanda; Sanderson, Kristy; Si, Lei; Yee, Kwang Chien; Palmer, Andrew J
2015-10-01
Hereditary haemochromatosis (HH) is a common genetic condition amongst people of northern European heritage. HH is associated with increased iron absorption leading to parenchymal organ damage and multiple arthropathies. Early diagnosis and treatment prevents complications. Population screening may increase early diagnosis, but no programmes have been introduced internationally: a paucity of health economic data is often cited as a barrier. To conduct a systematic review of all health economic studies in HH. Studies were identified through electronic searching of economic/biomedical databases. Any study on HH with original economic component was included. Study quality was formally assessed. Health economic data were extracted and analysed through narrative synthesis. Thirty-eight studies met the inclusion criteria. The majority of papers reported on costs or cost effectiveness of screening programmes. Whilst most concluded screening was cost effective compared with no screening, methodological flaws limit the quality of these findings. Assumptions regarding clinical penetrance, effectiveness of screening, health-state utility values (HSUVs), exclusion of early symptomatology (such as fatigue, lethargy and multiple arthropathies) and quantification of costs associated with HH were identified as key limitations. Treatment studies concluded therapeutic venepuncture was the most cost-effective intervention. There is a paucity of high-quality health economic studies relating to HH. The development of a comprehensive HH cost-effectiveness model utilising HSUVs is required to determine whether screening is worthwhile.
A qualitative review of immigrant women's experiences of maternal adaptation in South Korea.
Song, Ju-Eun; Ahn, Jeong-Ah; Kim, Tiffany; Roh, Eun Ha
2016-08-01
to synthesise the evidence of immigrant women's experiences of maternal adaptation in Korea. eligible studies were identified by searching MEDLINE, CINAHL, and the Korean electronic databases. Qualitative research studies, published in English and Korean addressing maternal adaptation experiences of immigrant women by marriage in Korea, were considered in the review. The suitability of the quality of articles was evaluated using the Joanna Briggs Institute's Critical Appraisal Checklist. Fifteen studies met the inclusion criteria for data analysis. Authors, purpose of the study, study design, theoretical framework, population (nationality and sample size), data collection (setting and method), and main study findings were extracted and summarised in a data extraction form for further narrative analysis and synthesis. A qualitative systematic review was performed by means of thematic synthesis. the literature search identified 7,628 articles, of which 15 studies, published between 2009 and 2014, were evaluated in the systematic review. Two overarching categories including five themes were identified in the qualitative studies related to maternal adaptation experiences; 'Experiences of motherhood transition' and 'Experiences of child-rearing'. these findings demonstrate the importance of understanding and improving maternal adaptation of immigrant women living in Korea. This can be achieved by enhancing social support, providing culturally sensitive maternal healthcare services, and expanding opportunities for immigrant women in education, job training, and economic independence. Copyright © 2016 Elsevier Ltd. All rights reserved.
Lovink, Marleen H; Persoon, Anke; Koopmans, Raymond T C M; Van Vught, Anneke J A H; Schoonhoven, Lisette; Laurant, Miranda G H
2017-09-01
To evaluate the effects of substituting nurse practitioners, physician assistants or nurses for physicians in long-term care facilities and primary healthcare for the ageing population (primary aim) and to describe what influences the implementation (secondary aim). Healthcare for the ageing population is undergoing major changes and physicians face heavy workloads. A solution to guarantee quality and contain costs might be to substitute nurse practitioners, physician assistants or nurses for physicians. A systematic literature review. PubMed, EMBASE, CINAHL, PsycINFO, CENTRAL, Web of Science; searched January 1995-August 2015. Study selection, data extraction and quality appraisal were conducted independently by two reviewers. Outcomes collected: patient outcomes, care provider outcomes, process of care outcomes, resource use outcomes, costs and descriptions of the implementation. Data synthesis consisted of a narrative summary. Two studies used a randomized design and eight studies used other comparative designs. The evidence of the two randomized controlled trials showed no effect on approximately half of the outcomes and a positive effect on the other half of the outcomes. Results of eight other comparative study designs point towards the same direction. The implementation was influenced by factors on a social, organizational and individual level. Physician substitution in healthcare for the ageing population may achieve at least as good patient outcomes and process of care outcomes compared with care provided by physicians. Evidence about resource use and costs is too limited to draw conclusions. © 2017 John Wiley & Sons Ltd.
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
DOE Office of Scientific and Technical Information (OSTI.GOV)
Petropoulou, V.; Vilchez, J.; Iglesias-Paramo, J.
2011-06-10
Spatially resolved spectroscopy has been obtained for a sample of 27 star-forming (SF) galaxies selected from our deep H{alpha} survey of the Hercules cluster. We have applied spectral synthesis models to all emission-line spectra of this sample using the population synthesis code STARLIGHT and have obtained fundamental parameters of stellar components such as mean metallicity and age. The emission-line spectra were corrected for underlying stellar absorption using these spectral synthesis models. Line fluxes were measured and O/H and N/O gas chemical abundances were obtained using the latest empirical calibrations. We have derived the masses and total luminosities of the galaxiesmore » using available Sloan Digital Sky Survey broadband photometry. The effects of cluster environment on the chemical evolution of galaxies and on their mass-metallicity (MZ) and luminosity-metallicity (LZ) relations were studied by combining the derived gas metallicities, the mean stellar metallicities and ages, the masses and luminosities of the galaxies, and their existing H I data. Our Hercules SF galaxies are divided into three main subgroups: (1) chemically evolved spirals with truncated ionized-gas disks and nearly flat oxygen gradients, demonstrating the effect of ram-pressure stripping; (2) chemically evolved dwarfs/irregulars populating the highest local densities, possible products of tidal interactions in preprocessing events; and (3) less metallic dwarf galaxies that appear to be 'newcomers' to the cluster and are experiencing pressure-triggered star formation. Most Hercules SF galaxies follow well-defined MZ and LZ sequences (for both O/H and N/O), though the dwarf/irregular galaxies located at the densest regions appear to be outliers to these global relations, suggesting a physical reason for the dispersion in these fundamental relations. The Hercules cluster appears to be currently assembling via the merger of smaller substructures, providing an ideal laboratory where the local environment has been found to be a key parameter in understanding the chemical history of galaxies.« less
Radio-flaring Ultracool Dwarf Population Synthesis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Route, Matthew, E-mail: mroute@purdue.edu
Over a dozen ultracool dwarfs (UCDs), low-mass objects of spectral types ≥M7, are known to be sources of radio flares. These typically several-minutes-long radio bursts can be up to 100% circularly polarized and have high brightness temperatures, consistent with coherent emission via the electron cyclotron maser operating in approximately kilogauss magnetic fields. Recently, the statistical properties of the bulk physical parameters that describe these UCDs have become described adequately enough to permit synthesis of the population of radio-flaring objects. For the first time, I construct a Monte Carlo simulator to model the population of these radio-flaring UCDs. This simulator ismore » powered by Intel Secure Key (ISK), a new processor technology that uses a local entropy source to improve random number generation that has heretofore been used to improve cryptography. The results from this simulator indicate that only ∼5% of radio-flaring UCDs within the local interstellar neighborhood (<25 pc away) have been discovered. I discuss a number of scenarios that may explain this radio-flaring fraction and suggest that the observed behavior is likely a result of several factors. The performance of ISK as compared to other pseudorandom number generators is also evaluated, and its potential utility for other astrophysical codes is briefly described.« less
Radio-flaring Ultracool Dwarf Population Synthesis
NASA Astrophysics Data System (ADS)
Route, Matthew
2017-08-01
Over a dozen ultracool dwarfs (UCDs), low-mass objects of spectral types ≥M7, are known to be sources of radio flares. These typically several-minutes-long radio bursts can be up to 100% circularly polarized and have high brightness temperatures, consistent with coherent emission via the electron cyclotron maser operating in approximately kilogauss magnetic fields. Recently, the statistical properties of the bulk physical parameters that describe these UCDs have become described adequately enough to permit synthesis of the population of radio-flaring objects. For the first time, I construct a Monte Carlo simulator to model the population of these radio-flaring UCDs. This simulator is powered by Intel Secure Key (ISK), a new processor technology that uses a local entropy source to improve random number generation that has heretofore been used to improve cryptography. The results from this simulator indicate that only ˜5% of radio-flaring UCDs within the local interstellar neighborhood (<25 pc away) have been discovered. I discuss a number of scenarios that may explain this radio-flaring fraction and suggest that the observed behavior is likely a result of several factors. The performance of ISK as compared to other pseudorandom number generators is also evaluated, and its potential utility for other astrophysical codes is briefly described.
Dissociation in victims of childhood abuse or neglect: a meta-analytic review.
Vonderlin, Ruben; Kleindienst, Nikolaus; Alpers, Georg W; Bohus, Martin; Lyssenko, Lisa; Schmahl, Christian
2018-04-10
Childhood abuse and neglect are associated with dissociative symptoms in adulthood. However, empirical studies show heterogeneous results depending on the type of childhood abuse or neglect and other maltreatment characteristics. In this meta-analysis, we systematically investigated the relationship between childhood interpersonal maltreatment and dissociation in 65 studies with 7352 abused or neglected individuals using the Dissociative Experience Scale (DES). We extracted DES-scores for abused and non-abused populations as well as information about type of abuse/neglect, age of onset, duration of abuse, and relationship to the perpetrator. Random-effects models were used for data synthesis, and meta-regression was used to predict DES-scores in abused populations from maltreatment characteristics. The results revealed higher dissociation in victims of childhood abuse and neglect compared with non-abused or neglected subsamples sharing relevant population features (MAbuse = 23.5, MNeglect = 18.8, MControl = 13.8) with highest scores for sexual and physical abuse. An earlier age of onset, a longer duration of abuse, and parental abuse significantly predicted higher dissociation scores. This meta-analysis underlines the importance of childhood abuse/neglect in the etiology of dissociation. The identified moderators may inform risk assessment and early intervention to prevent the development of dissociative symptoms.
Ebireri, Jennifer; Aderemi, Adewale V; Omoregbe, Nicholas; Adeloye, Davies
2016-07-05
Ischaemic heart disease (IHD) is currently ranked eighth among the leading causes of deaths in sub-Saharan Africa (sSA). Yet, effective population-wide preventive measures targeting risks in the region are still largely unavailable. We aimed to review population-wide and individual-level interventions addressing risk factors of IHD among adults in sSA. A systematic search of MEDLINE, EMBASE, Global Health and AJOL was conducted to identify studies focusing on population-wide and individual-level interventions targeting risks of IHD among adults in sSA. We conducted a detailed synthesis of basic findings of selected studies. A total of 2311 studies were identified, with only 9 studies meeting our selection criteria. 3 broad interventions were identified: dietary modifications, physical activity and community-based health promotion measures on tobacco and alcohol cessation. 3 studies reported significant reduction in blood pressure (BP), and another study reported statistically significant reduction in mean total cholesterol. Other outcome measures observed ranged from mild to no reduction in BP, blood glucose, body mass index and total cholesterol, respectively. We cannot specify with all certainty contextually feasible interventions that can be effective in modifying IHD risk factors in population groups across sSA. We recommend more research on IHD, particularly on the understanding of the burden, geared towards developing and/or strengthening preventive and treatment interventions for the disease in sSA. 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/
EMERGY SYNTHESIS OF AN AGRO-FOREST RESTORATION SYSTEM IN LOWER SUBTROPICAL CHINA
The low subtropical zone is the most populated and seriously degraded area in China; therefore, highly efficient restoration of degraded lands is the key to sustainable development of this region. An agro-forest restoration mode consisting of an Acacia mangium forest, a Citrus re...
Scaling with known uncertainty: a synthesis
Jianguo Wu; Harbin Li; K. Bruce Jones; Orie L. Loucks
2006-01-01
Scale is a fundamental concept in ecology and all sciences (Levin 1992, Wu and Loucks 1995, Barenblatt 1996), which has received increasing attention in recent years. The previous chapters have demonstrated an immerse diversity of scaling issues present in different areas of ecology, covering species distribution, population dynamics, ecosystem processes, and...
Intergenerational Learning in Organizations
ERIC Educational Resources Information Center
Ropes, Donald
2013-01-01
Purpose: The purpose of this paper is to explore the concept of intergenerational learning as a way for organizations to deal with an ageing worker population in a positive and constructive way. Design/methodology/approach: The paper employs a thematic synthesis of qualitative literature and considers all types of sources including quantitative…
Chapter 6. Synthesis of management and research considerations
Michael K. Young
1995-01-01
The five subspecies of cutthroat trout considered in this assessment share one characteristic: the loss of populations throughout their historical ranges. Similar causes have led to these losses: the introduction of nonnative fishes, overharvest, habitat degradation, and probably habitat fragmentation. Synergism among these effects remains unstudied, and we do not...
Broader context for social, economic, and cultural components
Patricia L. Winter; Jonathan W. Long; Frank K. Lake; Susan Charnley
2014-01-01
This chapter sets the context for the following sociocultural sections of the synthesis by providing information on the broader social, cultural, and economic patterns in the Sierra Nevada and southern Cascade Range. Demographic influences surrounding population change, including those accounted for through amenity migration, are examined. Social and cultural concerns...
ERIC Educational Resources Information Center
Bilias-Lolis, Evelyn; Gelber, Nicholas W.; Rispoli, Kristin M.; Bray, Melissa A.; Maykel, Cheryl
2017-01-01
This work offers a conceptual synthesis of several contemporary educational service delivery models that implicitly embed compassionate educational practices into supporting the learning and growth of diverse student populations. This manuscript discusses how such paradigms, such as culturally responsive positive behavior intervention and supports…
USDA-ARS?s Scientific Manuscript database
Continuous culture fermentor systems (CCFS) serve to evaluate the effect of diet on in vitro nutrient digestibility, fermentation, and microbial protein synthesis. Limitations of CCFS are: maintaining protozoa populations, and avoiding accumulation of undigested material in the vessels. Therefore, a...
Meta-Analysis: An Introduction Using Regression Models
ERIC Educational Resources Information Center
Rhodes, William
2012-01-01
Research synthesis of evaluation findings is a multistep process. An investigator identifies a research question, acquires the relevant literature, codes findings from that literature, and analyzes the coded data to estimate the average treatment effect and its distribution in a population of interest. The process of estimating the average…
Family Involvement in Education: A Synthesis of Research for Pacific Educators.
ERIC Educational Resources Information Center
Onikama, Denise L.; Hammond, Ormond W.; Koki, Stan
This report examines family involvement in elementary and secondary education, focusing on special concerns for schools in Hawaii and the Pacific Islands. The report identifies barriers to family involvement found among culturally diverse populations and suggests positive directions aimed at overcoming those barriers. Following an introduction,…
Catarino, Ana I; Cabral, Henrique N; Peeters, Kris; Pernet, Philippe; Punjabi, Usha; Dubois, Philippe
2008-07-01
The present study evaluated the effects of field metal contamination on sperm motility and the RNA/DNA ratio in echinoderms. Populations of Asterias rubens and Echinus acutus that occur naturally along a contamination gradient of sediments by cadmium, copper, lead, and zinc in a Norwegian fjord (the Sørfjord) were studied. Sperm motility, a measure of sperm quality, was quantified using a computer-assisted sperm analysis system. The RNA/DNA ratio, a measure of protein synthesis, was assessed by a one-dye (ethidium bromide)/one-enzyme (RNase), 96-well microplate fluorometric assay. Although both species accumulate metals at high concentrations, neither sperm motility parameters in A. rubens nor the RNA/DNA ratio in both species were affected. The Sørfjord is still one of the most metal-contaminated marine sites in Europe, but even so, populations of A. rubens and E. acutus are able to endure under these conditions.
Rosenblatt, Adam E.; Heithaus, Michael R.; Mather, Martha E.; Matich, Philip; Nifong, James C.; Ripple, William J.; Silliman, Brian R.
2013-01-01
During recent human history, human activities such as overhunting and habitat destruction have severely impacted many large top predator populations around the world. Studies from a variety of ecosystems show that loss or diminishment of top predator populations can have serious consequences for population and community dynamics and ecosystem stability. However, there are relatively few studies of the roles of large top predators in coastal ecosystems, so that we do not yet completely understand what could happen to coastal areas if large top predators are extirpated or significantly reduced in number. This lack of knowledge is surprising given that coastal areas around the globe are highly valued and densely populated by humans, and thus coastal large top predator populations frequently come into conflict with coastal human populations. This paper reviews what is known about the ecological roles of large top predators in coastal systems and presents a synthesis of recent work from three coastal eastern US Long Term Ecological Research (LTER) sites where long-term studies reveal what appear to be common themes relating to the roles of large top predators in coastal systems. We discuss three specific themes: (1) large top predators acting as mobile links between disparate habitats, (2) large top predators potentially affecting nutrient and biogeochemical dynamics through localized behaviors, and (3) individual specialization of large top predator behaviors. We also discuss how research within the LTER network has led to enhanced understanding of the ecological roles of coastal large top predators. Highlighting this work is intended to encourage further investigation of the roles of large top predators across diverse coastal aquatic habitats and to better inform researchers and ecosystem managers about the importance of large top predators for coastal ecosystem health and stability.
Human population history revealed by a supertree approach
Duda, Pavel; Jan Zrzavý
2016-01-01
Over the past two decades numerous new trees of modern human populations have been published extensively but little attention has been paid to formal phylogenetic synthesis. We utilized the “matrix representation with parsimony” (MRP) method to infer a composite phylogeny (supertree) of modern human populations, based on 257 genetic/genomic, as well as linguistic, phylogenetic trees and 44 admixture plots from 200 published studies (1990–2014). The resulting supertree topology includes the most basal position of S African Khoisan followed by C African Pygmies, and the paraphyletic section of all other sub-Saharan peoples. The sub-Saharan African section is basal to the monophyletic clade consisting of the N African–W Eurasian assemblage and the consistently monophyletic Eastern superclade (Sahul–Oceanian, E Asian, and Beringian–American peoples). This topology, dominated by genetic data, is well-resolved and robust to parameter set changes, with a few unstable areas (e.g., West Eurasia, Sahul–Melanesia) reflecting the existing phylogenetic controversies. A few populations were identified as highly unstable “wildcard taxa” (e.g. Andamanese, Malagasy). The linguistic classification fits rather poorly on the supertree topology, supporting a view that direct coevolution between genes and languages is far from universal. PMID:27431856
Kroman, S L; Roos, E M; Bennell, K L; Hinman, R S; Dobson, F
2014-01-01
To systematically appraise the evidence on measurement properties of performance-based outcome measures to assess physical function in young and middle-aged people known to be at high risk of hip and/or knee osteoarthritis (OA). Electronic searches were performed in MEDLINE, CINAHL, Scopus and SPORTDiscus in May 2013. Two reviewers independently rated the measurement properties using the 4-point COSMIN checklist. Best evidence synthesis was made using COSMIN quality, consistency and direction of findings and sample size. Twenty of 2736 papers were eligible for inclusion and 24 different performance-based outcome measures knee or obese populations were evaluated. No tests related to hip populations were included. Twenty-five measurement properties including reliability (nine studies), construct validity (hypothesis testing) (nine studies), measurement error (three studies), structural validity (two studies), interpretability (one study) and responsiveness (one study) were evaluated. A positive rating was given to 12.5% (30/240) of all possible measurement ratings. Tests were grouped into two categories based on the population characteristics. The one-legged hop for distance, followed by the 6-m timed hop and cross over hop for distance were the best-rated tests for the knee-injured population. Whereas the 6-min walk test was the only included test for the obese population. This review highlights the many gaps in knowledge about the measurement properties of performance-based outcome measures for young and middle-aged people known to be at high risk of hip and/or knee OA. There is a need for consensus on which outcome measures should be used and/or combined when assessing physical function in this population. Further good quality research is required. Copyright © 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
Belfort, Tatiana; Bramham, Jessica; Simões Neto, José Pedro; Sousa, Maria Fernanda Barroso de; Santos, Raquel Luiza dos; Nogueira, Marcela Moreira Lima; Torres, Bianca; Rosa, Rachel Dias Lopes da; Dourado, Marcia Cristina Nascimento
2015-01-01
Impairments in social and emotional functioning may affect the communication skills and interpersonal relationships of people with dementia and their caregivers. This study had the aim of presenting the steps involved in the cross-cultural adaptation of the Social and Emotional Questionnaire (SEQ) for the Brazilian population. Cross-cultural adaptation study, conducted at the Center for Alzheimer's Disease and Related Disorders in a public university. The process adopted in this study required six consecutive steps: initial translation, translation synthesis, back translation, committee of judges, pretesting of final version and submission to the original author. In general, the items had semantic, idiomatic, conceptual and experiential equivalence. During the first pretest, people with dementia and their caregivers had difficulties in understanding some items relating to social skills, which were interpreted ambiguously. New changes were made to allow better adjustment to the target population and, following this, a new pretest was performed. This pre-test showed that the changes were relevant and gave rise to the final version of the instrument. There was no correlation between education level and performance in the questionnaire, among people with dementia (P = 0.951). The Brazilian Portuguese version of the Social and Emotional Questionnaire was well understood and, despite the cultural and linguistic differences, the constructs of the original version were maintained.
Identification of Four Novel Loci in Asthma in European American and African American Populations.
Almoguera, Berta; Vazquez, Lyam; Mentch, Frank; Connolly, John; Pacheco, Jennifer A; Sundaresan, Agnes S; Peissig, Peggy L; Linneman, James G; McCarty, Catherine A; Crosslin, David; Carrell, David S; Lingren, Todd; Namjou-Khales, Bahram; Harley, John B; Larson, Eric; Jarvik, Gail P; Brilliant, Murray; Williams, Marc S; Kullo, Iftikhar J; Hysinger, Erik B; Sleiman, Patrick M A; Hakonarson, Hakon
2017-02-15
Despite significant advances in knowledge of the genetic architecture of asthma, specific contributors to the variability in the burden between populations remain uncovered. To identify additional genetic susceptibility factors of asthma in European American and African American populations. A phenotyping algorithm mining electronic medical records was developed and validated to recruit cases with asthma and control subjects from the Electronic Medical Records and Genomics network. Genome-wide association analyses were performed in pediatric and adult asthma cases and control subjects with European American and African American ancestry followed by metaanalysis. Nominally significant results were reanalyzed conditioning on allergy status. The validation of the algorithm yielded an average of 95.8% positive predictive values for both cases and control subjects. The algorithm accrued 21,644 subjects (65.83% European American and 34.17% African American). We identified four novel population-specific associations with asthma after metaanalyses: loci 6p21.31, 9p21.2, and 10q21.3 in the European American population, and the PTGES gene in African Americans. TEK at 9p21.2, which encodes TIE2, has been shown to be involved in remodeling the airway wall in asthma, and the association remained significant after conditioning by allergy. PTGES, which encodes the prostaglandin E synthase, has also been linked to asthma, where deficient prostaglandin E 2 synthesis has been associated with airway remodeling. This study adds to understanding of the genetic architecture of asthma in European Americans and African Americans and reinforces the need to study populations of diverse ethnic backgrounds to identify shared and unique genetic predictors of asthma.
Meta-analysis of few small studies in orphan diseases.
Friede, Tim; Röver, Christian; Wandel, Simon; Neuenschwander, Beat
2017-03-01
Meta-analyses in orphan diseases and small populations generally face particular problems, including small numbers of studies, small study sizes and heterogeneity of results. However, the heterogeneity is difficult to estimate if only very few studies are included. Motivated by a systematic review in immunosuppression following liver transplantation in children, we investigate the properties of a range of commonly used frequentist and Bayesian procedures in simulation studies. Furthermore, the consequences for interval estimation of the common treatment effect in random-effects meta-analysis are assessed. The Bayesian credibility intervals using weakly informative priors for the between-trial heterogeneity exhibited coverage probabilities in excess of the nominal level for a range of scenarios considered. However, they tended to be shorter than those obtained by the Knapp-Hartung method, which were also conservative. In contrast, methods based on normal quantiles exhibited coverages well below the nominal levels in many scenarios. With very few studies, the performance of the Bayesian credibility intervals is of course sensitive to the specification of the prior for the between-trial heterogeneity. In conclusion, the use of weakly informative priors as exemplified by half-normal priors (with a scale of 0.5 or 1.0) for log odds ratios is recommended for applications in rare diseases. © 2016 The Authors. Research Synthesis Methods published by John Wiley & Sons Ltd. © 2016 The Authors. Research Synthesis Methods published by John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Meng, Q. Y.; Svendsgaard, D.; Kotchmar, D. J.; Pinto, J. P.
2012-09-01
Although positive associations between ambient NO2 concentrations and personal exposures have generally been found by exposure studies, the strength of the associations varied among studies. Differences in results could be related to differences in study design and in exposure factors. However, the effects of study design, exposure factors, and sampling and measurement errors on the strength of the personal-ambient associations have not been evaluated quantitatively in a systematic manner. A quantitative research synthesis was conducted to examine these issues based on peer-reviewed publications in the past 30 years. Factors affecting the strength of the personal-ambient associations across the studies were also examined with meta-regression. Ambient NO2 was found to be significantly associated with personal NO2 exposures, with estimates of 0.42, 0.16, and 0.72 for overall pooled, longitudinal and daily average correlation coefficients based on random-effects meta-analysis. This conclusion was robust after correction for publication bias with correlation coefficients of 0.37, 0.16 and 0.45. We found that season and some population characteristics, such as pre-existing disease, were significant factors affecting the strength of the personal-ambient associations. More meaningful and rigorous comparisons would be possible if greater detail were published on the study design (e.g. local and indoor sources, housing characteristics, etc.) and data quality (e.g., detection limits and percent of data above detection limits).
Meta-synthesis of health behavior change meta-analyses.
Johnson, Blair T; Scott-Sheldon, Lori A J; Carey, Michael P
2010-11-01
We integrated and compared meta-analytic findings across diverse behavioral interventions to characterize how well they have achieved change in health behavior. Outcomes from 62 meta-analyses of interventions for change in health behavior were quantitatively synthesized, including 1011 primary-level investigations with 599,559 participants. Content coding suggested 6 behavioral domains: eating and physical activity, sexual behavior, addictive behaviors, stress management, female-specific screening and intervention behaviors, and behaviors involving use of health services. Behavior change interventions were efficacious (mean effect sizes = 0.08-0.45). Behavior change was more evident in more recent meta-analyses; those that sampled older interventions and literatures or sampled more published articles; those that included studies that relied on self-report, used briefer interventions, or sampled fewer, older, or female participants; and in some domains (e.g., stress management) more than others (e.g., sexual behaviors). Interventions improved health-related behaviors; however, efficacy varied as a function of participant and intervention characteristics. This meta-synthesis provides information about the efficacy of behavioral change interventions across health domains and populations; this knowledge can inform the design and development of public health interventions and future meta-analyses of these studies.
Influences of social power and normative support on condom use decisions: a research synthesis
Albarracín, D.; Kumkale, G. T.; Johnson, B. T.
2016-01-01
A meta-analysis of 58 studies involving 30,270 participants examined how study population and methodological characteristics influence the associations among norms, control perceptions, attitudes, intentions and behaviour in the area of condom use. Findings indicated that control perceptions generally correlated more strongly among members of societal groups that lack power, including female, younger individuals, ethnic-minorities and people with lower educational levels. Furthermore, norms generally had stronger influences among younger individuals and among people who have greater access to informational social support, including males, ethnic majorities and people with higher levels of education. These findings are discussed in the context of HIV prevention efforts. PMID:15370059
BIOGEOCHEMICAL STUDIES OF PHOTOSYNTHETIC MICROBIAL MATS AND THEIR BIOTA
NASA Technical Reports Server (NTRS)
DesMarais, David; Discipulo, M.; Turk, K.; Londry, K. L.
2005-01-01
Photosynthetic microbial mats offer an opportunity to define holistic functionality at the millimeter scale. At the same time. their biogeochemistry contributes to environmental processes on a planetary scale. These mats are possibly direct descendents of the most ancient biological communities; communities in which oxygenic photosynthesis might have been invented. Mats provide one of the best natural systems to study how microbial populations associate to control dynamic biogeochemical gradients. These are self- sustaining, complete ecosystems in which light energy absorbed over a dial (24 hour) cycle drives the synthesis of spatially-organized, diverse biomass. Tightly-coupled microorganisms in the mat have specialized metabolisms that catalyze transformations of carbon, nitrogen, sulfur, and a host of other elements.
Whole body protein metabolism in children with cancer.
Daley, S E; Pearson, A D; Craft, A W; Kernahan, J; Wyllie, R A; Price, L; Brock, C; Hetherington, C; Halliday, D; Bartlett, K
1996-01-01
Whole body protein synthesis and catabolism were measured using the [ring-2H5]phenylalanine and [1-13C]leucine primed constant infusion technique in 32 paediatric patients with cancer at different stages of treatment. Rates of synthesis (S) and catabolism (C) derived from the [ring-2H5]phenylalanine and [1-13C]leucine models were 4.7 (SD 1.3) (S) and 6.0 (1.5) (C) g/d/kg, and 5.5 (0.8) (S) and 6.8 (1.2) (C) g/d/kg, respectively. These results show that these two tracer techniques give similar results in this study population. Comparison of these values with results previously reported for groups of control children using the [ring-2H5]phenylalanine model (S = 3.69 and 3.93; C = 4.09 and 4.28 g/d/kg) and the [1-13C]leucine model (S = 4.32; C = 4.85 g/d/kg) show that rates of synthesis and catabolism were higher in cancer patients than in controls. Thus whole body protein turnover is increased in children under treatment for cancer. Other indices of metabolism such as plasma amino acids and intermediary metabolites were also measured and showed that, although subjects were in isotopic steady state, there were significant metabolic changes during the course of the primed constant infusions used to measure protein turnover. PMID:8984910
NASA Technical Reports Server (NTRS)
Broeze, R. J.; Pope, D. H.
1978-01-01
The inhibition of translation which is observed after shifting Escherichia coli to low temperature was investigated. 70 S ribosomes were isolated from E. coli 8 hours after a shift to 5 C synthesized protein in the absence of added mRNA (i.e., endogenous protein synthesis by 70 S monosomes) at a rate which was three times greater than the rate of endogenous protein synthesis by 70 S ribosomes which were isolated at the time of the shift to 5 C. Calculations based on the rates of endogenous protein synthesis and polyphenylalanine synthesis indicate that 70 S monosomes comprise only 0.1% of the total E. coli 70 S ribosome population after 8 hours at 5 c. Experiments designed to test initiation complex formation on ApUpG or formaldehyde treated MS-2 viral RNA demonstrated that, although the rate of formation of 30 S initiation complexes was not inhibited, the rate of formation of active 70 S initiation complexes, able to react with puromycin, was inhibited to a great extent at 5 C. A model depicting the effects of low temperature on the E. coli translation system is proposed.
NASA Astrophysics Data System (ADS)
Winter, H.; Christopher-Allison, E.; Brown, A. L.; Goforth, A. M.
2018-04-01
Herein, we report an aerobic synthesis method to produce bismuth nanoparticles (Bi NPs) with average diameters in the range 40-80 nm using commercially available bismuth triiodide (BiI3) as the starting material; the method uses only readily available chemicals and conventional laboratory equipment. Furthermore, size data from replicates of the synthesis under standard reaction conditions indicate that this method is highly reproducible in achieving Bi NP populations with low standard deviations in the mean diameters. We also investigated the mechanism of the reaction, which we determined results from the reduction of a soluble alkylammonium iodobismuthate precursor species formed in situ. Under appropriate concentration conditions of iodobismuthate anion, we demonstrate that burst nucleation of Bi NPs results from reduction of Bi3+ by the coordinated, redox non-innocent iodide ligands when a threshold temperature is exceeded. Finally, we demonstrate phase transfer and silica coating of the Bi NPs, which results in stable aqueous colloids with retention of size, morphology, and colloidal stability. The resultant, high atomic number, hydrophilic Bi NPs prepared using this synthesis method have potential for application in emerging x-ray contrast and x-ray therapeutic applications.
Trotter, R Talbot; Keena, Melody A
2016-12-01
Efforts to manage and eradicate invasive species can benefit from an improved understanding of the physiology, biology, and behavior of the target species, and ongoing efforts to eradicate the Asian longhorned beetle (Anoplophora glabripennis Motschulsky) highlight the roles this information may play. Here, we present a climate-driven phenology model for A. glabripennis that provides simulated life-tables for populations of individual beetles under variable climatic conditions that takes into account the variable number of instars beetles may undergo as larvae. Phenology parameters in the model are based on a synthesis of published data and studies of A. glabripennis, and the model output was evaluated using a laboratory-reared population maintained under varying temperatures mimicking those typical of Central Park in New York City. The model was stable under variations in population size, simulation length, and the Julian dates used to initiate individual beetles within the population. Comparison of model results with previously published field-based phenology studies in native and invasive populations indicates both this new phenology model, and the previously published heating-degree-day model show good agreement in the prediction of the beginning of the flight season for adults. However, the phenology model described here avoids underpredicting the cumulative emergence of adults through the season, in addition to providing tables of life stages and estimations of voltinism for local populations. This information can play a key role in evaluating risk by predicting the potential for population growth, and may facilitate the optimization of management and eradication efforts. 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.
Use of Atorvastatin in Lipid Disorders and Cardiovascular Disease in Chinese Patients
Ye, Yi-Cong; Zhao, Xi-Liang; Zhang, Shu-Yang
2015-01-01
Objective: Statins are still underused for the prevention of cardiovascular disease (CVD) in China. Hence, we conducted a systemic review on the pharmacology, clinical efficacy, and adverse events of atorvastatin, as well as on patient adherence. Data Sources: We conducted a systemic search in PubMed with the following keywords: “atorvastatin” (Supplementary concept) or “atorvastatin” (All field) and (“China” [AD] or “China” [all field] or “Chinese” [All field]). Study Selection: Clinical or basic research articles on atorvastatin were included. Results: Atorvastatin is a reversible and competitive inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, decreasing the de novo cholesterol synthesis. The pharmacokinetics of atorvastatin among Chinese is similar to those in Caucasians, and several gene polymorphisms have proved to be associated with the metabolism of atorvastatin in the Chinese population. Several international multiple-center randomized control trials have demonstrated the benefit of atorvastatin for primary and secondary prevention of CVD. None of them, however, included the Chinese, and current evidence in the population is still inadequate, due to the small sample size, low study quality, short study duration, and the use of surrogate endpoints instead of clinical endpoints. The overall incidence of adverse events observed with atorvastatin did not increase in the 10–80 mg dose range, and was similar to that observed with placebo and in patients treated with other statins, which makes atorvastatin well-tolerated in the Chinese population. Moreover, high patient adherence was observed in clinical studies. Conclusions: Based on the current available evidence, there is no significant difference between Chinese and non-Chinese population in term of pharmacology and clinical efficacy/safety. High-quality evidence is still needed to support the use of atorvastatin in high-risk Chinese population. PMID:25591572
GalMod: A Galactic Synthesis Population Model
NASA Astrophysics Data System (ADS)
Pasetto, Stefano; Grebel, Eva K.; Chiosi, Cesare; Crnojević, Denija; Zeidler, Peter; Busso, Giorgia; Cassarà, Letizia P.; Piovan, Lorenzo; Tantalo, Rosaria; Brogliato, Claudio
2018-06-01
We present a new Galaxy population synthesis Model, GalMod. GalMod is a star-count model featuring an asymmetric bar/bulge as well as spiral arms and related extinction. The model, initially introduced in Pasetto et al., has been here completed with a central bar, a new bulge description, new disk vertical profiles, and several new bolometric corrections. The model can generate synthetic mock catalogs of visible portions of the Milky Way, external galaxies like M31, or N-body simulation initial conditions. At any given time, e.g., at a chosen age of the Galaxy, the model contains a sum of discrete stellar populations, namely the bulge/bar, disk, and halo. These populations are in turn the sum of different components: the disk is the sum of the spiral arms, thin disks, a thick disk, and various gas components, while the halo is the sum of a stellar component, a hot coronal gas, and a dark-matter component. The Galactic potential is computed from these population density profiles and used to generate detailed kinematics by considering up to the first four moments of the collisionless Boltzmann equation. The same density profiles are then used to define the observed color–magnitude diagrams in a user-defined field of view (FoV) from an arbitrary solar location. Several photometric systems have been included and made available online, and no limits on the size of the FoV are imposed thus allowing full-sky simulations, too. Finally, we model the extinction by adopting a dust model with advanced ray-tracing solutions. The model's Web page (and tutorial) can be accessed at www.GalMod.org and support is provided at Galaxy.Model@yahoo.com.
GalMod: the last frontier of Galaxy population synthesis models
NASA Astrophysics Data System (ADS)
Pasetto, Stefano; Kollmeier, Juna; Grebel, Eva K.; chiosi, cesare
2018-01-01
We present a novel Galaxy population synthesis model: GalMod (Pasetto et al. 2016, 2017a,b) is the only star-count model featuring an asymmetric bar/bulge as well as spiral arms as directly obtained by applying linear perturbative theory to self-consistent distribution function of the Galaxy stellar populations. Compared to previous literature models (e.g., Besancon, Trilegal), GalMod allows to generate full-sky mock catalogue, M31 surveys and provides a better match to observed Milky Way (MW) stellar fields.The model can generate synthetic mock catalogs of visible portions of the MW, external galaxies like M31, or N-body simulation initial conditions. At any given time, e.g., a chosen age of the Galaxy, the model contains a sum of discrete stellar populations, namely bulge/bar, disk, halo. The disk population is itself the sum of subpopulations: spiral arms, thin disk, thick disk, and gas component, while the halo is modeled as the sum of a stellar component, a hot coronal gas, and a dark matter component. The Galactic potential is computed from these subpopulations' density profiles and used to generate detailed kinematics by considering the first few moments of the Boltzmann collisionless equation for all the stellar subpopulations. The same density profiles are then used to define the observed color-magnitude diagrams within an input field of view from an arbitrary solar location. Several photometric systems have been included and made available on-line, e.g., SDSS, Gaia, 2MASS, HST WFC3, and others. Finally, we model the extinction with advanced ray tracing solutions.The model's web page (and tutorial) can be accessed at www.GalMod.org.
Cyril, Sheila; Smith, Ben J.; Possamai-Inesedy, Alphia; Renzaho, Andre M. N.
2015-01-01
Background Although community engagement (CE) is widely used in health promotion, components of CE models associated with improved health are poorly understood. This study aimed to examine the magnitude of the impact of CE on health and health inequalities among disadvantaged populations, which methodological approaches maximise the effectiveness of CE, and components of CE that are acceptable, feasible, and effective when used among disadvantaged populations. Design The systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We carried out methodological assessments of the included studies using rating scales. The analysis focussed on model synthesis to identify the key CE components linked to positive study outcomes and comparative analysis between positive study outcomes, processes, and quality indicators of CE. Results Out of 24 studies that met our inclusion criteria, 21 (87.5%) had positively impacted health behaviours, public health planning, health service access, health literacy, and a range of health outcomes. More than half of the studies (58%) were of good quality, whereas 71% and 42% of studies showed good community involvement in research and achieved high levels of CE, respectively. Key CE components that affected health outcomes included real power-sharing, collaborative partnerships, bidirectional learning, incorporating the voice and agency of beneficiary communities in research protocol, and using bicultural health workers for intervention delivery. Conclusions The findings suggest that CE models can lead to improved health and health behaviours among disadvantaged populations if designed properly and implemented through effective community consultation and participation. We also found several gaps in the current measurement of CE in health intervention studies, which suggests the importance of developing innovative approaches to measure CE impact on health outcomes in a more rigorous way. PMID:26689460
Koblentz, Gregory D
In March 2017, the American biotech company Tonix announced that a Canadian scientist had synthesized horsepox virus as part of a project to develop a safer vaccine against smallpox. The first de novo synthesis of an orthopoxvirus, a closely related group of viruses that includes horsepox and the variola virus that causes smallpox, crosses an important Rubicon in the field of biosecurity. The synthesis of horsepox virus takes the world one step closer to the reemergence of smallpox as a threat to global health security. That threat has been held at bay for the past 40 years by the extreme difficulty of obtaining variola virus and the availability of effective medical countermeasures. The techniques demonstrated by the synthesis of horsepox have the potential to erase both of these barriers. The primary risk posed by this research is that it will open the door to the routine and widespread synthesis of other orthopoxviruses, such as vaccinia, for use in research, public health, and medicine. The normalization and globalization of orthopoxvirus synthesis for these beneficial applications will create a cadre of laboratories and scientists that will also have the capability and expertise to create infectious variola virus from synthetic DNA. Unless the safeguards against the synthesis of variola virus are strengthened, the capability to reintroduce smallpox into the human population will be globally distributed and either loosely or completely unregulated, providing the foundation for a disgruntled or radicalized scientist, sophisticated terrorist group, unscrupulous company, or rogue state to recreate one of humanity's most feared microbial enemies. The reemergence of smallpox-because of a laboratory accident or an intentional release-would be a global health disaster. International organizations, national governments, the DNA synthesis industry, and the synthetic biology community all have a role to play in devising new approaches to preventing the reemergence of smallpox.
Lahiri, Shaon; van Ommeren, Mark; Roberts, Bayard
2017-12-01
Our aim was to systematically review how social functioning is measured, conceptualised, impacted, and associated with mental disorders in populations affected by humanitarian crises. Quantitative studies conducted with civilian populations affected by humanitarian crises in low- and middle-income countries with outcomes of social functioning were examined up to 2014. Data sources included Medline, Embase, PsycInfo, and Global Health, and 8 grey literature sources, yielding 14,350 records, of which 20 studies met inclusion criteria. A descriptive synthesis analysis was used, and the final selected studies assessed for quality using a modified Newcastle-Ottawa Scale. In the 20 studies, social functioning was conceptualised in 6 categories: family functioning, friendship quality, functional impairment, overall social functioning, social adaptation, and social relations. Seventeen studies were cross-sectional, two were cohort, and one a controlled trial. The quality of the studies was generally moderate. The limited evidence suggests that social functioning is a relevant variable. Greater crisis exposure is associated with more severe depression and lower social functioning. The protective role of familial and social resources for social functioning is highlighted in different crisis settings. However, greater research on social functioning and mental health is required.
Thompson, E L; O'Connor, W; Parker, L; Ross, P; Raftos, D A
2015-03-01
Previous work suggests that larvae from Sydney rock oysters that have been selectively bred for fast growth and disease resistance are more resilient to the impacts of ocean acidification than nonselected, wild-type oysters. In this study, we used proteomics to investigate the molecular differences between oyster populations in adult Sydney rock oysters and to identify whether these form the basis for observations seen in larvae. Adult oysters from a selective breeding line (B2) and nonselected wild types (WT) were exposed for 4 weeks to elevated pCO2 (856 μatm) before their proteomes were compared to those of oysters held under ambient conditions (375 μatm pCO2 ). Exposure to elevated pCO2 resulted in substantial changes in the proteomes of oysters from both the selectively bred and wild-type populations. When biological functions were assigned, these differential proteins fell into five broad, potentially interrelated categories of subcellular functions, in both oyster populations. These functional categories were energy production, cellular stress responses, the cytoskeleton, protein synthesis and cell signalling. In the wild-type population, proteins were predominantly upregulated. However, unexpectedly, these cellular systems were downregulated in the selectively bred oyster population, indicating cellular dysfunction. We argue that this reflects a trade-off, whereby an adaptive capacity for enhanced mitochondrial energy production in the selectively bred population may help to protect larvae from the effects of elevated CO2 , whilst being deleterious to adult oysters. © 2015 John Wiley & Sons Ltd.
The Infrared Telescope Facility (IRTF) Spectral Library: Cool Stars
NASA Astrophysics Data System (ADS)
Rayner, John T.; Cushing, Michael C.; Vacca, William D.
2009-12-01
We present a 0.8-5 μm spectral library of 210 cool stars observed at a resolving power of R ≡ λ/Δλ ~ 2000 with the medium-resolution infrared spectrograph, SpeX, at the 3.0 m NASA Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii. The stars have well-established MK spectral classifications and are mostly restricted to near-solar metallicities. The sample not only contains the F, G, K, and M spectral types with luminosity classes between I and V, but also includes some AGB, carbon, and S stars. In contrast to some other spectral libraries, the continuum shape of the spectra is measured and preserved in the data reduction process. The spectra are absolutely flux calibrated using the Two Micron All Sky Survey photometry. Potential uses of the library include studying the physics of cool stars, classifying and studying embedded young clusters and optically obscured regions of the Galaxy, evolutionary population synthesis to study unresolved stellar populations in optically obscured regions of galaxies and synthetic photometry. The library is available in digital form from the IRTF Web site.
Olivares, Astrid; Laskin, Julia; Johnson, Grant E
2014-09-18
The scalable synthesis of ligated subnanometer metal clusters containing an exact number of atoms is of interest due to the highly size-dependent catalytic, electronic, and optical properties of these species. While significant research has been conducted on the batch preparation of clusters through reduction synthesis in solution, the processes of metal complex reduction as well as cluster nucleation, growth, and postreduction etching are still not well understood. Herein, we demonstrate a prototype temperature-controlled flow reactor for qualitatively studying cluster formation in solution at steady-state conditions. Employing this technique, methanol solutions of a chloro(triphenylphosphine)gold precursor, 1,4-bis(diphenylphosphino)butane capping ligand, and borane-tert-butylamine reducing agent were combined in a mixing tee and introduced into a heated capillary with a known length. In this manner, the temperature dependence of the relative abundance of different ionic reactants, intermediates, and products synthesized in real time was characterized qualitatively using online mass spectrometry. A wide distribution of doubly and triply charged cationic gold clusters was observed as well as smaller singly charged organometallic complexes. The results demonstrate that temperature plays a crucial role in determining the relative population of cationic gold clusters and, in general, that higher temperature promotes the formation of doubly charged clusters and singly charged organometallic complexes while reducing the abundance of triply charged species. Moreover, the distribution of clusters observed at elevated temperatures is found to be consistent with that obtained at longer reaction times at room temperature, thereby demonstrating that heating may be used to access cluster distributions characteristic of different stages of batch reduction synthesis in solution.
Alphonse, Peter A S; Ramprasath, Vanu; Jones, Peter J H
2017-01-01
Dietary cholesterol and plant sterols differentially modulate cholesterol kinetics and circulating cholesterol. Understanding how healthy individuals with their inherent variabilities in cholesterol trafficking respond to such dietary sterols will aid in improving strategies for effective cholesterol lowering and alleviation of CVD risk. The objectives of this study were to assess plasma lipid responsiveness to dietary cholesterol v. plant sterol consumption, and to determine the response in rates of cholesterol absorption and synthesis to each sterol using stable isotope approaches in healthy individuals. A randomised, double-blinded, crossover, placebo-controlled clinical trial (n 49) with three treatment phases of 4-week duration were conducted in a Manitoba Hutterite population. During each phase, participants consumed one of the three treatments as a milkshake containing 600 mg/d dietary cholesterol, 2 g/d plant sterols or a control after breakfast meal. Plasma lipid profile was determined and cholesterol absorption and synthesis were measured by oral administration of [3, 4-13C] cholesterol and 2H-labelled water, respectively. Dietary cholesterol consumption increased total (0·16 (sem 0·06) mmol/l, P=0·0179) and HDL-cholesterol (0·08 (sem 0·03) mmol/l, P=0·0216) concentrations with no changes in cholesterol absorption or synthesis. Plant sterol consumption failed to reduce LDL-cholesterol concentrations despite showing a reduction (6 %, P=0·0004) in cholesterol absorption. An over-compensatory reciprocal increase in cholesterol synthesis (36 %, P=0·0026) corresponding to a small reduction in absorption was observed with plant sterol consumption, possibly resulting in reduced LDL-cholesterol lowering efficacy of plant sterols. These data suggest that inter-individual variability in cholesterol trafficking mechanisms may profoundly impact plasma lipid responses to dietary sterols in healthy individuals.
Gälman, Cecilia; Miquel, Juan Francisco; Pérez, Rosa Maria; Einarsson, Curt; Ståhle, Lars; Marshall, Guillermo; Nervi, Flavio; Rudling, Mats
2004-03-01
Gallstone disease is an important, costly health-care problem in Western societies. It is still unclear whether hepatic lipid regulatory enzymes play primary or secondary roles in gallstone formation. In this study, the aim was to investigate whether the synthesis of bile acids and cholesterol is increased in gallstone disease and to test whether such a metabolic change, if present, might occur before gallstone formation. A total of 125 Chilean Hispanic women (80 without gallstones and 45 with gallstones) matched for age and body mass index were investigated, along with 40 Chilean Mapuche Indian women (20 without gallstones and 20 with gallstones), a population group in which the prevalence for gallstone disease is very high. Fasting blood plasma samples were assayed for 7 alpha-hydroxy-4-cholesten-3-one and lathosterol, 2 strong indicators for hepatic bile acid and body cholesterol synthesis, respectively. Plasma 7 alpha-hydroxy-4-cholesten-3-one levels, corrected for plasma cholesterol, were significantly increased by 50% in Hispanic women with gallstones as compared with gallstone-free Hispanics (P < 0.006). As compared with Hispanic women without gallstones, plasma 7 alpha-hydroxy-4-cholesten-3-one levels were increased by > or =100% (P < 0.002) in Mapuche Indian women, independently of whether gallstones were present. Plasma lathosterol, corrected for plasma cholesterol, was significantly increased by 22% in Hispanic women with gallstones and in Mapuche Indian women compared with Hispanic women. The results indicate that the synthesis of bile acids and cholesterol is induced in gallstone disease and precedes gallstone development. These inductions presumably occur as a response to an increased intestinal loss of bile acids.
Anatskaia, O V; Malikov, V G; Meĭer, M N; Kudriavtsev, B N
1995-01-01
A cytophotometric measurement of DNA content in hepatocytes of maturing mouse-like hamsters was made. Cells belonging to ordinary mammalian ploidy classes 2c, 2c x 2, 4c, and 4c x 2 made about 90% of the hepatocyte population. The share of binucleated cells wa high (about 80%), the majority of these cells being 2c X 2 hepatocytes. Binucleated cells with tetraploid and diploid nuclei occur in almost every animal. An average hepatocyte ploidy level in mouse-like hamster is 4.6c. The main peculiarity of parenchymal liver cell populations is that up 5% of hepatocytes contain 3--11 nuclei of different ploidy classes. Multinucleated cells increase in number from 1.5% to 4% within the period from one year (the age of maturation) to two years. Later on their percentage does not change. It is found that in binucleated and multinucleated hepatocytes DNA synthesis can proceed asynchronously. Asynchrony in DNA synthesis elevates as the number of nuclei increases. Among the 2c x 2 and 2c x 3 cells an uneven distribution of 3H-thymidine label can occur, respectively, in 5 and in 50% cases, whereas all the cells with more than 3 nuclei display an uneven an uneven 3H-thymidin label distribution. The formation of multinucleated cells is supposed to be associated with asynchrony in DNA-synthesis in binucleated cells and with the restitution of mitosis.
Central mechanisms for force and motion--towards computational synthesis of human movement.
Hemami, Hooshang; Dariush, Behzad
2012-12-01
Anatomical, physiological and experimental research on the human body can be supplemented by computational synthesis of the human body for all movement: routine daily activities, sports, dancing, and artistic and exploratory involvements. The synthesis requires thorough knowledge about all subsystems of the human body and their interactions, and allows for integration of known knowledge in working modules. It also affords confirmation and/or verification of scientific hypotheses about workings of the central nervous system (CNS). A simple step in this direction is explored here for controlling the forces of constraint. It requires co-activation of agonist-antagonist musculature. The desired trajectories of motion and the force of contact have to be provided by the CNS. The spinal control involves projection onto a muscular subset that induces the force of contact. The projection of force in the sensory motor cortex is implemented via a well-defined neural population unit, and is executed in the spinal cord by a standard integral controller requiring input from tendon organs. The sensory motor cortex structure is extended to the case for directing motion via two neural population units with vision input and spindle efferents. Digital computer simulations show the feasibility of the system. The formulation is modular and can be extended to multi-link limbs, robot and humanoid systems with many pairs of actuators or muscles. It can be expanded to include reticular activating structures and learning. Copyright © 2012 Elsevier Ltd. All rights reserved.
Marbà-Ardébol, Anna-Maria; Bockisch, Anika; Neubauer, Peter; Junne, Stefan
2018-02-01
Physiological responses of yeast to oscillatory environments as they appear in the liquid phase in large-scale bioreactors have been the subject of past studies. So far, however, the impact on the sterol content and intracellular regulation remains to be investigated. Since oxygen is a cofactor in several reaction steps within sterol metabolism, changes in oxygen availability, as occurs in production-scale aerated bioreactors, might have an influence on the regulation and incorporation of free sterols into the cell lipid layer. Therefore, sterol and fatty acid synthesis in two- and three-compartment scale-down Saccharomyces cerevisiae cultivation were studied and compared with typical values obtained in homogeneous lab-scale cultivations. While cells were exposed to oscillating substrate and oxygen availability in the scale-down cultivations, growth was reduced and accumulation of carboxylic acids was increased. Sterol synthesis was elevated to ergosterol at the same time. The higher fluxes led to increased concentrations of esterified sterols. The cells thus seem to utilize the increased availability of precursors to fill their sterol reservoirs; however, this seems to be limited in the three-compartment reactor cultivation due to a prolonged exposure to oxygen limitation. Besides, a larger heterogeneity within the single-cell size distribution was observed under oscillatory growth conditions with three-dimensional holographic microscopy. Hence the impact of gradients is also observable at the morphological level. The consideration of such a single-cell-based analysis provides useful information about the homogeneity of responses among the population. Copyright © 2017 John Wiley & Sons, Ltd.
Seeking help for perinatal psychological distress: a meta-synthesis of women's experiences.
Button, Susan; Thornton, Alexandra; Lee, Suzanne; Shakespeare, Judy; Ayers, Susan
2017-10-01
Women may not seek help for perinatal psychological distress, despite regular contact with primary care services. Barriers include ignorance of symptoms, inability to disclose distress, others' attitudes, and cultural expectations. Much of the evidence has been obtained from North American populations and may not, therefore, extrapolate to the UK. To understand the factors affecting women's decision to seek help for perinatal distress. Meta-synthesis of the available published qualitative evidence on UK women's experiences of seeking help for perinatal distress. Systematic searches were conducted in accordance with PRISMA guidelines. Databases searched were PubMed, Scopus, PsycINFO, PsycARTICLES, CINAHL, and Academic Search Complete. Searches of grey literature and references were also conducted. Studies were eligible for inclusion if they reported qualitative data on UK women's experiences of perinatal distress and contact with healthcare professionals. The synthesis was conducted using meta-ethnography. In all, 24 studies were eligible for inclusion. Metasynthesis identified three main themes: identifying a problem, the influence of healthcare professionals, and stigma. These themes build on current understanding of help seeking by identifying the need for women to be able to frame their experience, for healthcare professionals to educate women about their roles, the need for continuity of care, and the way that being seen as a 'bad mother' causes women to self-silence. Perinatal care provision needs to allow for continuity of care and for staff training that facilitates awareness of factors that influence women's help seeking. Further research is required, particularly in relation to effective means of identifying perinatal psychological distress. © British Journal of General Practice 2017.
Evolution of Optical Binary Fraction in Sparse Stellar Systems
NASA Astrophysics Data System (ADS)
Li, Zhongmu; Mao, Caiyan
2018-05-01
This work studies the evolution of the fraction of optical binary stars (OBF; not including components such as neutron stars and black holes), which is caused by stellar evolution, and the contributions of various binaries to OBF via the stellar population synthesis technique. It is shown that OBF decreases from 1 to about 0.81 for stellar populations with the Salpeter initial mass function (IMF), and to about 0.85 for the case of the Kroupa IMF, on a timescale of 15 Gyr. This result depends on metallicity, slightly. The contributions of binaries varying with mass ratio, orbital period, separation, spectral types of primary and secondary, contact degree, and pair type to OBF are calculated for stellar populations with different ages and metallicities. The contribution of different kinds of binaries to OBF depends on age and metallicity. The results can be used for estimating the global OBF of star clusters or galaxies from the fraction of a kind of binary. It is also helpful for estimating the primordial and future binary fractions of sparse stellar systems from the present observations. Our results are suitable for studying field stars, open clusters, and the outer part of globular clusters, because the OBF of such objects is affected by dynamical processes, relatively slightly, but they can also be used for giving some limits for other populations.
Thomas, S; Fayter, D; Misso, K; Ogilvie, D; Petticrew, M; Sowden, A; Whitehead, M; Worthy, G
2008-01-01
Objective: To assess the effects of population tobacco control interventions on social inequalities in smoking. Data sources: Medical, nursing, psychological, social science and grey literature databases, bibliographies, hand-searches and contact with authors. Study selection: Studies were included (n = 84) if they reported the effects of any population-level tobacco control intervention on smoking behaviour or attitudes in individuals or groups with different demographic or socioeconomic characteristics. Data extraction: Data extraction and quality assessment for each study were conducted by one reviewer and checked by a second. Data synthesis: Data were synthesised using graphical (“harvest plot”) and narrative methods. No strong evidence of differential effects was found for smoking restrictions in workplaces and public places, although those in higher occupational groups may be more likely to change their attitudes or behaviour. Smoking restrictions in schools may be more effective in girls. Restrictions on sales to minors may be more effective in girls and younger children. Increasing the price of tobacco products may be more effective in reducing smoking among lower-income adults and those in manual occupations, although there was also some evidence to suggest that adults with higher levels of education may be more price-sensitive. Young people aged under 25 are also affected by price increases, with some evidence that boys and non-white young people may be more sensitive to price. Conclusions: Population-level tobacco control interventions have the potential to benefit more disadvantaged groups and thereby contribute to reducing health inequalities. PMID:18426867
Shi Shiu, Chen; Voisin, Dexter R; Chen, Wet-Ti; Lo, Yi-An; Hardestry, Melissa; Nguyen, Huong
2016-05-01
Over the past two decades, there has emerged a body of literature documenting a number of risk factors associated with Asian/Pacific Islander men who have sex with men's unsafe sexual behaviors. This study aims to systematically review existing empirical studies and synthesize research results into a social-ecological framework using a mixed research synthesis. Empirical research articles published in peer-reviewed journals between January 1990 and June 2013 were identified in six databases, including PubMed, Ovid MEDLINE, PsycINFO, Social Work Abstract, CINAL, and Web of Knowledge. Both quantitative and qualitative studies were included. Two analysts independently reviewed the articles, and findings were organized on a social-ecological framework. Twenty-two articles were included in the analysis; among these 13 were quantitative, 8 were qualitative, and 1 was mixed-methods research. Results indicated that demographic characteristics, psychological resources, behavioral patterns, relationships with family and friends, dynamics with romantic or sexual partners, community involvement, culture, discrimination, and institutional factors were related to unprotected anal intercourse. This article presents a critique of this literature and discusses implications for future research with this population. It concludes with prevention/intervention initiatives based on review findings. © The Author(s) 2015.
Shiu, Chen Shi; Voisin, Dexter R.; Chen, Wet-Ti; Lo, Yi-An; Hardestry, Melissa; Nguyen, Huong
2017-01-01
Over the past two decades, there has emerged a body of literature documenting a number of risk factors associated with Asian/Pacific Islander men who have sex with men’s unsafe sexual behaviors. This study aims to systematically review existing empirical studies and synthesize research results into a social–ecological framework using a mixed research synthesis. Empirical research articles published in peer-reviewed journals between January 1990 and June 2013 were identified in six databases, including PubMed, Ovid MEDLINE, PsycINFO, Social Work Abstract, CINAL, and Web of Knowledge. Both quantitative and qualitative studies were included. Two analysts independently reviewed the articles, and findings were organized on a social–ecological framework. Twenty-two articles were included in the analysis; among these 13 were quantitative, 8 were qualitative, and 1 was mixed-methods research. Results indicated that demographic characteristics, psychological resources, behavioral patterns, relationships with family and friends, dynamics with romantic or sexual partners, community involvement, culture, discrimination, and institutional factors were related to unprotected anal intercourse. This article presents a critique of this literature and discusses implications for future research with this population. It concludes with prevention/intervention initiatives based on review findings. PMID:25563383
NASA Technical Reports Server (NTRS)
Silk, Joseph; Schramm, David N.
1992-01-01
Attention is drawn to a potentially observable flux of diffuse extragalactic gamma rays produced by inelastic cosmic-ray interactions that is inevitably a by-product of spallation-synthesized Be. The epoch of cosmic ray-induced Population II light element nucleosynthesis is constrained to be at redshift greater than 0.5. A spectral feature in the diffuse extragalactic gamma-ray background with amplitude 0.1 above 10 MeV is predicted if the Be is synthesized at z less than 10. The possibility is discussed that the cosmic-ray flux responsible for Population II Be and B synthesis may be associated with a precursor hypothesized Population III.
The metabolism of plant sterols is disturbed in postmenopausal women with coronary artery disease.
Gylling, Helena; Hallikainen, Maarit; Rajaratnam, Radhakrishnan A; Simonen, Piia; Pihlajamäki, Jussi; Laakso, Markku; Miettinen, Tatu A
2009-03-01
In postmenopausal coronary artery disease (CAD) women, serum plant sterols are elevated. Thus, we investigated further whether serum plant sterols reflect absolute cholesterol metabolism in CAD as in other populations and whether the ABCG5 and ABCG8 genes, associated with plant sterol metabolism, were related to the risk of CAD. In free-living postmenopausal women with (n = 47) and without (n = 62) CAD, serum noncholesterol sterols including plant sterols were analyzed with gas-liquid chromatography, cholesterol absorption with peroral isotopes, absolute cholesterol synthesis with sterol balance technique, and bile acid synthesis with quantitating fecal bile acids. In CAD women, serum plant sterol ratios to cholesterol were 21% to 26% (P < .05) higher than in controls despite similar cholesterol absorption efficiency. Absolute cholesterol and bile acid synthesis were reduced. Only in controls were serum plant sterols related to cholesterol absorption (eg, sitosterol; in controls: r = 0.533, P < .001; in CAD: r = 0.296, P = not significant). However, even in CAD women, serum lathosterol (relative synthesis marker) and lathosterol-cholestanol (relative synthesis-absorption marker) were related to absolute synthesis and absorption percentage (P range from .05 to <.001) similarly to controls. Frequencies of the common polymorphisms of ABCG5 and ABCG8 genes did not differ between coronary and control women. In conclusion, plant sterol metabolism is disturbed in CAD women; so serum plant sterols only tended to reflect absolute cholesterol absorption. Other relative markers of cholesterol metabolism were related to the absolute ones in both groups. ABCG5 and ABCG8 genes were not associated with the risk of CAD.
NASA Astrophysics Data System (ADS)
Hecht, C.; Kronemayer, H.; Dreier, T.; Wiggers, H.; Schulz, C.
2009-01-01
The iron-atom concentration distribution as well as the gas-phase temperature was measured via laser-induced fluorescence (LIF) during iron-oxide nanoparticle synthesis in a low-pressure hydrogen/oxygen/argon flame reactor using ironpentacarbonyl (Fe(CO)5) as precursor. Temperature measurements based on multi-line NO-LIF imaging are used to correct for temperature-dependent ground-state populations. The concentration measurement is calibrated based on line-of-sight absorption measurements. The influence of the precursor on the flame is observed at precursor concentrations larger than 70 ppm as the flame front moves closer to the burner surface with increasing Fe(CO)5 concentration.
Panayidou, Klea; Gsteiger, Sandro; Egger, Matthias; Kilcher, Gablu; Carreras, Máximo; Efthimiou, Orestis; Debray, Thomas P A; Trelle, Sven; Hummel, Noemi
2016-09-01
The performance of a drug in a clinical trial setting often does not reflect its effect in daily clinical practice. In this third of three reviews, we examine the applications that have been used in the literature to predict real-world effectiveness from randomized controlled trial efficacy data. We searched MEDLINE, EMBASE from inception to March 2014, the Cochrane Methodology Register, and websites of key journals and organisations and reference lists. We extracted data on the type of model and predictions, data sources, validation and sensitivity analyses, disease area and software. We identified 12 articles in which four approaches were used: multi-state models, discrete event simulation models, physiology-based models and survival and generalized linear models. Studies predicted outcomes over longer time periods in different patient populations, including patients with lower levels of adherence or persistence to treatment or examined doses not tested in trials. Eight studies included individual patient data. Seven examined cardiovascular and metabolic diseases and three neurological conditions. Most studies included sensitivity analyses, but external validation was performed in only three studies. We conclude that mathematical modelling to predict real-world effectiveness of drug interventions is not widely used at present and not well validated. © 2016 The Authors Research Synthesis Methods Published by John Wiley & Sons Ltd. © 2016 The Authors Research Synthesis Methods Published by John Wiley & Sons Ltd.
Ekeland, E; Heian, F; Hagen, K; Coren, E
2005-01-01
Twenty three randomised controlled trials were analysed. A synthesis of several small, low quality trials indicates that exercise may have short term beneficial effects on self esteem in children and adolescents. However, high quality research on defined populations with adequate follow up is needed. PMID:16244186
Teaching Excellence for All Our Students
ERIC Educational Resources Information Center
King, Sabrina Hope; Watson, Audra
2010-01-01
Education has the power to change the world. We wrote this article in the spirit of the hope embodied by the election of President Obama and the critical need for improved teaching to benefit all the nation's students. This article offers a synthesis of the characteristics of excellent teaching for the diverse student population. This article…
This report uses results from a previous report titled Assessment of the Impacts of Global Change on Regional U.S. Air Quality: A Synthesis of Climate Change Impacts on Ground-Level Ozone, a number of high-resolution, spatially explicit population projections developed ...
USDA-ARS?s Scientific Manuscript database
Condensed tannins (CT) can alter ruminal fermentation and enteric methane (CH4) production in ruminants; however, research is lacking on how increased CT levels affect nutrient digestibility, volatile fatty acid (VFA) production, bacterial protein synthesis, fatty acid (FA) profiles, protozoal popul...
ERIC Educational Resources Information Center
Simmons, Denise R.; Creamer, Elizabeth G.; Yu, Rongrong
2017-01-01
Co-curricular and extracurricular involvement plays important roles in students' cognitive and effective development, educational effectiveness and satisfaction, and sense of belonging. Moreover, these practices can help equip a diverse population with the academic and professional skills necessary to succeed in the technological workforce. Yet…
Social vulnerability and climate change: synthesis of literature
Kathy Lynn; Katharine MacKendrick; Ellen M. Donoghue
2011-01-01
The effects of climate change are expected to be more severe for some segments of society than others because of geographic location, the degree of association with climate-sensitive environments, and unique cultural, economic, or political characteristics of particular landscapes and human populations. Social vulnerability and equity in the context of climate change...
USDA-ARS?s Scientific Manuscript database
Monounsaturated fatty acids (MUFAs) are unsaturated fatty acids with one double bond and are derived from endogenous synthesis and dietary intake. Accumulating evidence has suggested that plasma and erythrocyte MUFA levels were associated with cardiometabolic disorders including cardiovascular disea...
Conceptualizing and measuring demand for recreation on national forests: a review and synthesis.
Brian E. Garber-Yonts
2005-01-01
This analysis examines the problem of measuring demand for recreation on national forests and other public lands. Current measures of recreation demand in Forest Service resource assessments and planning emphasize population-level participation rates and activity-based economic values for visitor days. Alternative measures and definitions of recreation demand are...
Posttraumatic Stress in Mothers Related to Giving Birth Prematurely: A Mixed Research Synthesis.
Beck, Cheryl Tatano; Harrison, Lisa
Globally the preterm birth rate for 184 countries in 2010 was 11.1%. Preterm births can be a traumatic experience for mothers. This article provides a mixed research synthesis of the quantitative and qualitative studies on posttraumatic stress in mothers who have given birth prematurely. Narrative synthesis was the mixed research synthesis approach used. Included in this narrative synthesis were quantitative prevalence studies ( n = 19), quantitative intervention studies ( n = 6), and qualitative studies ( n = 5). Prevalence rates ranged from 14% to 79%. Four of the intervention studies had significant results and two did not. Qualitative data synthesis revealed five themes: (a) shocked and horrified, (b) consuming guilt, (c) pervasive anxiety and hypervigilance, (d) intrusive thoughts, and (e) numbing and avoiding reminders. Women's traumatic experiences of preterm birth are clearly important issues for psychiatric nurses to address.
Dopa decarboxylase (Ddc) affects variation in Drosophila longevity.
De Luca, Maria; Roshina, Nataliya V; Geiger-Thornsberry, Gretchen L; Lyman, Richard F; Pasyukova, Elena G; Mackay, Trudy F C
2003-08-01
Mutational analyses in model organisms have shown that genes affecting metabolism and stress resistance regulate life span, but the genes responsible for variation in longevity in natural populations are largely unidentified. Previously, we mapped quantitative trait loci (QTLs) affecting variation in longevity between two Drosophila melanogaster strains. Here, we show that the longevity QTL in the 36E;38B cytogenetic interval on chromosome 2 contains multiple closely linked QTLs, including the Dopa decarboxylase (Ddc) locus. Complementation tests to mutations show that Ddc is a positional candidate gene for life span in these strains. Linkage disequilibrium (LD) mapping in a sample of 173 alleles from a single population shows that three common molecular polymorphisms in Ddc account for 15.5% of the genetic contribution to variance in life span from chromosome 2. The polymorphisms are in strong LD, and the effects of the haplotypes on longevity suggest that the polymorphisms are maintained by balancing selection. DDC catalyzes the final step in the synthesis of the neurotransmitters, dopamine and serotonin. Thus, these data implicate variation in the synthesis of bioamines as a factor contributing to natural variation in individual life span.
Regulation of Hemoglobin β-Chain Synthesis in Bone Marrow Erythroid Cells by α Chains
Wolf, Jeffrey L.; Mason, R. George; Honig, George R.
1973-01-01
Synthesis of α and β chains of hemoglobin was studied in vitro in intact reticulocytes and bone marrow cells. The cells were from rabbits having a variant form of hemoglobin in which L-isoleucine is in the α but not in the β chains. This characteristic permitted a selective inhibition of α-chain synthesis to be produced by addition to the incubation medium of L-O-methylthreonine, an inhibitor of protein synthesis that is a specific antagonist of L-isoleucine. In studies with reticulocytes, 25 mM L-O-methylthreonine produced a 60-70% inhibition of α-chain synthesis, but β-chain synthesis was unaffected even after incubation times for 4 hr. Because reticulocytes contain a pool of uncombined α chains which might have obscured the demonstration of an α chain-dependent mechanism for β-chain synthesis, subsequent studies were done with bone marrow cells. The latter had little or no detectable α-chain pool. A substantial inhibition of α-chain synthesis by the bone marrow cells was produced by the isoleucine antagonist but was also accompanied by a significantly decreased rate of β-chain synthesis. These findings suggest that the coordinated synthesis of the complementary α- and β-globin chains of hemoglobin may reflect in part a modifying effect of α-chain synthesis on the synthesis of β chains. PMID:4519634
Beliefs and perception about mental health issues: a meta-synthesis
Choudhry, Fahad Riaz; Mani, Vasudevan; Ming, Long Chiau; Khan, Tahir Mehmood
2016-01-01
Background Mental health literacy is the beliefs and knowledge about mental health issues and their remedies. Attitudes and beliefs of lay individuals about mental illness are shaped by personal knowledge about mental illness, knowing and interacting with someone living with mental illness, and cultural stereotypes. Mental health issues are increasing and are alarming in almost every part of the world, and hence compiling this review provides an opportunity to understand the different views regarding mental disorders and problems as well as to fill the gap in the published literature by focusing only on the belief system and perception of mental health problems among general population. Method The methodology involved a systematic review and the meta-synthesis method, which includes synthesizing published qualitative studies on mental health perception and beliefs. Sample Fifteen relevant published qualitative and mixed-method studies, regarding the concept of mental health, were identified for meta-synthesis. Analysis All the themes of the selected studies were further analyzed to give a broader picture of mental health problems and their perceived causes and management. Only qualitative studies, not older than 2010, focusing on beliefs about, attitudes toward, and perceptions of mental health problems, causes, and treatments were included in this review. Results The findings are divided into four major categories, namely, 1) symptoms of mental health issues, 2) description of mental health issues, 3) perceived causes, and 4) preferred treatment and help-seeking behavior. Each category contains themes and subthemes based on published studies. Conclusion The findings reveal multiple causes of, descriptions of, and treatment options for mental health problems, thereby providing insight into different help-seeking behaviors. Clarity is offered by highlighting cultural differences and similarities in mental health beliefs and perceptions about the causes of mental health problems. The implications of the studies and recommendations based on current findings are also discussed. PMID:27826193
The progenitors of supernovae Type Ia
NASA Astrophysics Data System (ADS)
Toonen, Silvia
2014-09-01
Despite the significance of Type Ia supernovae (SNeIa) in many fields in astrophysics, SNeIa lack a theoretical explanation. SNeIa are generally thought to be thermonuclear explosions of carbon/oxygen (CO) white dwarfs (WDs). The canonical scenarios involve white dwarfs reaching the Chandrasekhar mass, either by accretion from a non-degenerate companion (single-degenerate channel, SD) or by a merger of two CO WDs (double-degenerate channel, DD). The study of SNeIa progenitors is a very active field of research for binary population synthesis (BPS) studies. The strength of the BPS approach is to study the effect of uncertainties in binary evolution on the macroscopic properties of a binary population, in order to constrain binary evolutionary processes. I will discuss the expected SNeIa rate from the BPS approach and the uncertainties in their progenitor evolution, and compare with current observations. I will also discuss the results of the POPCORN project in which four BPS codes were compared to better understand the differences in the predicted SNeIa rate of the SD channel. The goal of this project is to investigate whether differences in the simulated populations are due to numerical effects or whether they can be explained by differences in the input physics. I will show which assumptions in BPS codes affect the results most and hence should be studied in more detail.
McGinn, Tony; McColgan, Mary; Taylor, Brian
2017-01-01
To add to our understanding of change processes by analyzing perpetrators' perspectives on intervention. Fourteen databases were searched and 27 articles reporting relevant qualitative findings were identified. Analytic coding was applied across the findings and discussion sections of all 27 study reports to form an interpretive account of the data set. Studies were also grouped according to their perceived theoretical standpoints, and a summary of themes in each grouping is presented. Study participants were largely positive about their experiences in intervention; new learning such as conflict interruption techniques and new communication skills were commonly cited benefits. Perpetrators attend perpetrator intervention programs with a range of motivations, ranging from a determination to change who they are, to a determination to avoid a custodial sentence. The most common barriers to change, found in this analysis, were cognitive distortions, emotional dysregulation, gendered social constructions, and self-esteem issues. Further qualitative investigation, of rigor, with the intention-to-treat population of intimate partner violence perpetrators involved in perpetrator programs is needed. At this point, we would venture that qualitative research, with perpetrators, underlines the precept that formidable barriers to change exist in this population. The centrality of group work to perpetrator interventions should be reconsidered in light of the complexity of the change task and in light of the heterogeneity of this population.
Extending and expanding the Darwinian synthesis: the role of complex systems dynamics.
Weber, Bruce H
2011-03-01
Darwinism is defined here as an evolving research tradition based upon the concepts of natural selection acting upon heritable variation articulated via background assumptions about systems dynamics. Darwin's theory of evolution was developed within a context of the background assumptions of Newtonian systems dynamics. The Modern Evolutionary Synthesis, or neo-Darwinism, successfully joined Darwinian selection and Mendelian genetics by developing population genetics informed by background assumptions of Boltzmannian systems dynamics. Currently the Darwinian Research Tradition is changing as it incorporates new information and ideas from molecular biology, paleontology, developmental biology, and systems ecology. This putative expanded and extended synthesis is most perspicuously deployed using background assumptions from complex systems dynamics. Such attempts seek to not only broaden the range of phenomena encompassed by the Darwinian Research Tradition, such as neutral molecular evolution, punctuated equilibrium, as well as developmental biology, and systems ecology more generally, but to also address issues of the emergence of evolutionary novelties as well as of life itself. Copyright © 2010 Elsevier Ltd. All rights reserved.
Complex structure of the carbon arc discharge for synthesis of nanotubes
Vekselman, V.; Feurer, M.; Huang, T.; ...
2017-06-06
Comprehensive non-invasive spectroscopic techniques and electrical measurements of the carbon arc revealed two distinguishable plasma synthesis regions in the radial direction normal to the arc axis. These regions, which are defined as the arc core and the arc periphery, are shown to have very different compositions of carbon species with different densities and temperatures. The colder arc periphery is dominated by carbon diatomic molecules (C 2), which are in the minority in the composition of the hot arc core. These differences are due to a highly non-uniform distribution of the arc current, which is mainly conducted through the arc coremore » populated with carbon atoms and ions. Therefore, the ablation of the graphite anode is governed by the arc core, while the formation of carbon molecules occurs in the colder arc periphery. Furthermore, this result is consistent with previous predictions that the plasma environment in the arc periphery is suitable for synthesis of carbon nanotubes.« less
Brodsky, V Y; Malchenko, L A; Lazarev, D S; Butorina, N N; Dubovaya, T K; Zvezdina, N D
2018-03-01
The kinetics of protein synthesis was investigated in primary cultures of hepatocytes from old rats in serum-free medium. The rats were fed mixed fodder supplemented with glutamic acid and then transferred to a regular mixed fodder. The amplitude of protein synthesis rhythm in hepatocytes isolated from these rats increased on average 2-fold in comparison with the rats not receiving glutamic acid supplement. Based on this indicator reflecting the degree of cell-cell interactions, the cells from old rats were not different from those of young rats. The effect was preserved for 3-4 days. These results are discussed in connection with our previous data on preservation of the effect of single administration of gangliosides, noradrenaline, serotonin, and other synchronizers on various cell populations. In contrast to the other investigated factors, glutamic acid is capable of penetrating the blood-brain barrier, which makes its effect possible not only in the case of hepatocytes and other non-brain cells, but also in neurons.
Sound texture perception via statistics of the auditory periphery: Evidence from sound synthesis
McDermott, Josh H.; Simoncelli, Eero P.
2014-01-01
Rainstorms, insect swarms, and galloping horses produce “sound textures” – the collective result of many similar acoustic events. Sound textures are distinguished by temporal homogeneity, suggesting they could be recognized with time-averaged statistics. To test this hypothesis, we processed real-world textures with an auditory model containing filters tuned for sound frequencies and their modulations, and measured statistics of the resulting decomposition. We then assessed the realism and recognizability of novel sounds synthesized to have matching statistics. Statistics of individual frequency channels, capturing spectral power and sparsity, generally failed to produce compelling synthetic textures. However, combining them with correlations between channels produced identifiable and natural-sounding textures. Synthesis quality declined if statistics were computed from biologically implausible auditory models. The results suggest that sound texture perception is mediated by relatively simple statistics of early auditory representations, presumably computed by downstream neural populations. The synthesis methodology offers a powerful tool for their further investigation. PMID:21903084
Complex structure of the carbon arc discharge for synthesis of nanotubes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vekselman, V.; Feurer, M.; Huang, T.
Comprehensive non-invasive spectroscopic techniques and electrical measurements of the carbon arc revealed two distinguishable plasma synthesis regions in the radial direction normal to the arc axis. These regions, which are defined as the arc core and the arc periphery, are shown to have very different compositions of carbon species with different densities and temperatures. The colder arc periphery is dominated by carbon diatomic molecules (C 2), which are in the minority in the composition of the hot arc core. These differences are due to a highly non-uniform distribution of the arc current, which is mainly conducted through the arc coremore » populated with carbon atoms and ions. Therefore, the ablation of the graphite anode is governed by the arc core, while the formation of carbon molecules occurs in the colder arc periphery. Furthermore, this result is consistent with previous predictions that the plasma environment in the arc periphery is suitable for synthesis of carbon nanotubes.« less
Exploring reservoir dynamics: a case study of rabies in the Serengeti ecosystem
Lembo, Tiziana; Hampson, Katie; Haydon, Daniel T.; Craft, Meggan; Dobson, Andy; Dushoff, Jonathan; Ernest, Eblate; Hoare, Richard; Kaare, Magai; Mlengeya, Titus; Mentzel, Christine; Cleaveland, Sarah
2012-01-01
Summary Knowledge of infection reservoir dynamics is critical for effective disease control, but identifying reservoirs of multi-host pathogens is challenging. Here, we synthesize several lines of evidence to investigate rabies reservoirs in complex carnivore communities of the Serengeti ecological region in northwest Tanzania, where the disease has been confirmed in 12 carnivore species.Long-term monitoring data suggest that rabies persists in high-density domestic dog Canis familiaris populations (> 11 dogs km−2) and occurs less frequently in lower-density (< 5 dogs km−2) populations and only sporadically in wild carnivores.Genetic data show that a single rabies virus variant belonging to the group of southern Africa canid-associated viruses (Africa 1b) circulates among a range of species, with no evidence of species-specific virus–host associations.Within-species transmission was more frequently inferred from high-resolution epidemiological data than between-species transmission. Incidence patterns indicate that spill-over of rabies from domestic dog populations sometimes initiates short-lived chains of transmission in other carnivores.Synthesis and applications. The balance of evidence suggests that the reservoir of rabies in the Serengeti ecosystem is a complex multi-host community where domestic dogs are the only population essential for persistence, although other carnivores contribute to the reservoir as non-maintenance populations. Control programmes that target domestic dog populations should therefore have the greatest impact on reducing the risk of infection in all other species including humans, livestock and endangered wildlife populations, but transmission in other species may increase the level of vaccination coverage in domestic dog populations necessary to eliminate rabies. PMID:22427710
Population Synthesis Studies of the White Dwarfs of the Galactic Disk and Halo
NASA Astrophysics Data System (ADS)
Cojocaru, Elena-Ruxandra
2016-09-01
White dwarfs are fossil stars that can encode valuable information about the formation, evolution and other properties of the different Galactic stellar populations. They are the direct descendants of main-sequence stars with masses ranging from ∼0.8 M⊙ to ∼10 M⊙, which means that over 95% of the stars in our Galaxy will eventually become white dwarfs. This fact, correlated with the excellent quality of modern white dwarf cooling models, clearly marks their potential as cosmic clocks for estimating the ages of Galactic stellar populations, as well as place white dwarfs as privileged objects in understanding several actual astrophysical problems. Stellar population synthesis methods (Tinsley, 1968) use theoretical evolutionary sequences to reproduce luminosities, temperatures and other parameters building up to a synthetic population that can be readily compared to an observed sample of stars. Such techniques are perfect for the study of the different white dwarf populations in our Galaxy and their strength has only grown in recent years, fueled both by improved evolutionary sequences and detailed cooling tracks and also by the ever growing samples of white dwarfs identified through modern survey missions. In particular, the work presented in this thesis uses an updated population synthesis code based on previous versions of the code from our group (García-Berro et al., 1999; Torres et al., 2002; García-Berro et al., 2004; Torres et al., 2005; Camacho et al., 2014). Our synthetic population code, based on Monte Carlo statistical techniques, has been extensively used in the study of the disk (García-Berro et al., 1! 999; Torres et al., 2001; Torres & García-Berro, 2016) and halo (Torres et al., 2002; García-Berro et al., 2004) single white-dwarf population, white dwarf plus main sequence stars (Camacho et al., 2014), as well as open clusters such as NGC 6791 (García-Berro et al., 2010; García-Berro et al., 2011) or globular clusters, as 47 Tuc (García-Berro et al., 2014). In this thesis we investigate different properties of single and binary white dwarf populations in the Galactic disk and halo. We first study the effect of progenitor metallicity on the thin disk white dwarf luminosity function. Stellar metallicity is an important parameter in computing both main-sequence evolutionary sequences and white dwarf cooling tracks. At the same, studies of the metallicity distribution function for the Galactic disk have shown that both high and low-metallicity stars can be found throughout the entire mass range, although a clear dependence between age and metallicity has yet to be proven and more recent findings actually show little correlation. With this in mind, we test two different age-metallicity relations, one assuming a Gaussian distribution of metallicity around the Solar value, the other one a decreasing relation between age and metallicity. We take into account the influence of metallicity on both main sequence lifetimes and white dwarf s! tellar parameters. Finally, we compute the theoretical white dwarf luminosity function applying the observational selection criteria of two different surveys, the Sloan Digital Sky Survey (SDSS) and the Supercosmos Sky Survey (SSS). Next, we compute the white dwarf luminosity, mass and cumulative age functions derived from a sample of DA white dwarfs obtained from the LAMOST Spectroscopic Survey of the Galactic anti-center (LSS-GAC). We also derive the local space density and the formation rate for DA white dwarf. Given that both the observed mass distribution obtained from this sample and that derived from the local sample of white dwarfs present an apparent excess of massive white dwarfs, we investigate the possibility of accounting for this excess by reproducing the white dwarf population of the thin disk under different sets of initial assumptions, accounting also for selection criteria and observational biases. Another issue that we investigate is the robustness of the halo white dwarf luminosity function employing different models for the initial mass function, density profile and stellar formation history. We also analyze if the white dwarf luminosity function can be used as a means to discriminate the role played by residual hydrogen burning in the atmospheres of low-mass white dwarfs. This process is known to become a significant source of energy for white dwarfs descending from very low metallicity progenitors, such as those that characterize the Galactic halo population. Lastly, we simulate the white dwarf-main sequence (WD+MS) binary population of the Galactic disk and compare it to the parameter distributions from the largest and most recent WD+MS catalog derived from the SDSS (Rebassa-Mansergas et al., 2016b). We not only reproduce the selection criteria, but we also account for spectroscopic completeness, observational errors and other biases that affect the sample. We use the observed population as a benchmark for constraining several important physical quantities specific to binary evolution, such as the initial mass ratio distribution and also the common envelope parametrization. This thesis is based on three published papers, Cojocaru et al. (2014), Rebassa-Mansergas et al. (2015) and Cojocaru et al. (2015) and another work in preparation.
In situ and in vitro colonization of Cathaya argyrophylla (Pinaceae) by ectomycorrhizal fungi.
Vaario, Lu-Min; Xing, Shu-Tang; Xie, Zong-Qiang; Lun, Zhi-Ming; Sun, Xue; Li, Yu Hua
2006-03-01
Cathaya argyrophylla, a critically endangered conifer, is found to grow at four isolated areas located in subtropical mountains of China. To examine the involvement and usefulness of mycorrhizas for sustaining the population of this tree, we compared the root system, morphology, and structure of mycorrhizal roots of C. argyrophylla, which were collected from a natural stand and an artificial stand, each grown at a different location. More mycorrhizal roots were found for trees from an artificial stand. The presence of extramatrical mycelium, mantle, and Hartig net revealed that C. argyrophylla formed an ectomycorrhizal association in both sampling sites. Starch granules were found in mycorrhizal roots collected only from a natural stand. The aseptic synthesis of C. argyrophylla and Cenococcum geophilum was established for the first time in vitro. Typical ectomycorrhizas formed on seedlings on RM medium containing 0.1 g/l glucose, 5 weeks after inoculation. By light microscopy, the synthesized mycorrhizas showed a thin mantle from which emanated extramatrical hyphae and highly branched Hartig net. A simple, rapid, and convenient mycorrhiza synthesis system was developed, which facilitates further studies on ectomycorrhizal development of C. argyrophylla.
Land cover, land use changes and air pollution in Asia: a synthesis
NASA Astrophysics Data System (ADS)
Vadrevu, Krishna; Ohara, Toshimasa; Justice, Chris
2017-12-01
A better understanding of land cover/land use changes (LCLUC) and their interactions with the atmospheric environment is essential for the sustainable management of natural resources, environmental protection, air quality, agricultural planning and food security. The 15 papers published in this focus issue showcase a variety of studies relating to drivers and impacts of LCLUC and air pollution in different South/Southeast Asian (S/SEA) countries. This synthesis article, in addition to giving context to the articles in this focus issue, also reviews the broad linkages between population, LCLUC and air pollution. Additionally, we identify knowledge gaps and research priorities that are essential in addressing air pollution issues in the region. We conclude that for effective pollution mitigation in S/SEA countries, quantifying drivers, sources and impacts of pollution need a thorough data analysis through ground-based instrumentation, models and integrated research approaches. We also stress the need for the development of sustainable technologies and strengthening the scientific and resource management communities through capacity building and training activities to address air pollution issues in S/SEA countries.
Nutritional status, functional capacity and exercise rehabilitation in end-stage renal disease.
Mercer, T H; Koufaki, P; Naish, P F
2004-05-01
A significant percentage of patients with end-stage renal disease are malnourished and/or muscle wasted. Uremia is associated with decreased protein synthesis and increased protein degradation. Fortunately, nutritional status has been shown to be a modifiable risk factor in the dialysis population. It has long been proposed that exercise could positively alter the protein synthesis-degradation balance. Resistance training had been considered as the only form of exercise likely to induce anabolism in renal failure patients. However, a small, but growing, body of evidence indicates that for some dialysis patients, favourable improvements in muscle atrophy and fibre hypertrophy can be achieved via predominantly aerobic exercise training. Moreover, some studies tentatively suggest that nutritional status, as measured by SGA, can also be modestly improved by modes and patterns of exercise training that have been shown to also increase muscle fibre cross-sectional area and improve functional capacity. Functional capacity tests can augment the information content of basic nutritional status assessments of dialysis patients and as such are recommended for routine inclusion as a feature of all nutritional status assessments.
Trend estimation in populations with imperfect detection
Kery, Marc; Dorazio, Robert M.; Soldaat, Leo; Van Strien, Arco; Zuiderwijk, Annie; Royle, J. Andrew
2009-01-01
1. Trends of animal populations are of great interest in ecology but cannot be directly observed owing to imperfect detection. Binomial mixture models use replicated counts to estimate abundance, corrected for detection, in demographically closed populations. Here, we extend these models to open populations and illustrate them using sand lizard Lacerta agilis counts from the national Dutch reptile monitoring scheme. 2. Our model requires replicated counts from multiple sites in each of several periods, within which population closure is assumed. Counts are described by a hierarchical generalized linear model, where the state model deals with spatio-temporal patterns in true abundance and the observation model with imperfect counts, given that true state. We used WinBUGS to fit the model to lizard counts from 208 transects with 1–10 (mean 3) replicate surveys during each spring 1994–2005. 3. Our state model for abundance contained two independent log-linear Poisson regressions on year for coastal and inland sites, and random site effects to account for unexplained heterogeneity. The observation model for detection of an individual lizard contained effects of region, survey date, temperature, observer experience and random survey effects. 4. Lizard populations increased in both regions but more steeply on the coast. Detectability increased over the first few years of the study, was greater on the coast and for the most experienced observers, and highest around 1 June. Interestingly, the population increase inland was not detectable when the observed counts were analysed without account of detectability. The proportional increase between 1994 and 2005 in total lizard abundance across all sites was estimated at 86% (95% CRI 35–151). 5. Synthesis and applications. Open-population binomial mixture models are attractive for studying true population dynamics while explicitly accounting for the observation process, i.e. imperfect detection. We emphasize the important conceptual benefit provided by temporal replicate observations in terms of the interpretability of animal counts.
Kramer, Irene Fleur; Verdijk, Lex B; Hamer, Henrike M; Verlaan, Sjors; Luiking, Yvette C; Kouw, Imre W K; Senden, Joan M; van Kranenburg, Janneau; Gijsen, Annemarie P; Bierau, Jörgen; Poeze, Martijn; van Loon, Luc J C
2017-10-01
Studying the muscle protein synthetic response to food intake in elderly is important, as it aids the development of interventions to combat sarcopenia. Although sarcopenic elderly are the target group for many of these nutritional interventions, no studies have assessed basal or post-prandial muscle protein synthesis rates in this population. To assess the basal and post-prandial muscle protein synthesis rates between healthy and sarcopenic older men. A total of 15 healthy (69 ± 1 y) and 15 sarcopenic (81 ± 1 y) older men ingested a leucine-enriched whey protein nutritional supplement containing 21 g of protein, 9 g of carbohydrate, and 3 g of fat. Stable isotope methodology combined with frequent collection of blood and muscle samples was applied to assess basal and post-prandial muscle protein fractional synthetic rates. Handgrip strength, muscle mass, and gait speed were assessed to identify sarcopenia, according to international criteria. Basal mixed muscle protein fractional synthetic rates (FSR) averaged 0.040 ± 0.005 and 0.032 ± 0.003%/h (mean ± SEM) in the sarcopenic and healthy group, respectively (P = 0.14). Following protein ingestion, FSR increased significantly to 0.055 ± 0.004 and 0.053 ± 0.004%/h in the post-prandial period in the sarcopenic (P = 0.003) and healthy groups (P < 0.001), respectively, with no differences between groups (P = 0.45). Furthermore, no differences were observed between groups in muscle protein synthesis rates during the early (0.058 ± 0.007 vs 0.060 ± 0.008%/h, sarcopenic vs healthy, respectively) and late (0.052 ± 0.004 vs 0.048 ± 0.003%/h) stages of the post-prandial period (P = 0.93 and P = 0.34, respectively). Basal muscle protein synthesis rates are not lower in sarcopenic older men compared to healthy older men. The ingestion of 21 g of a leucine-enriched whey protein effectively increases muscle protein synthesis rates in both sarcopenic and healthy older men. Public trial registry number: NTR3047. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
NASA Astrophysics Data System (ADS)
Forgan, D. H.; Hall, C.; Meru, F.; Rice, W. K. M.
2018-03-01
It is likely that most protostellar systems undergo a brief phase where the protostellar disc is self-gravitating. If these discs are prone to fragmentation, then they are able to rapidly form objects that are initially of several Jupiter masses and larger. The fate of these disc fragments (and the fate of planetary bodies formed afterwards via core accretion) depends sensitively not only on the fragment's interaction with the disc, but also with its neighbouring fragments. We return to and revise our population synthesis model of self-gravitating disc fragmentation and tidal downsizing. Amongst other improvements, the model now directly incorporates fragment-fragment interactions while the disc is still present. We find that fragment-fragment scattering dominates the orbital evolution, even when we enforce rapid migration and inefficient gap formation. Compared to our previous model, we see a small increase in the number of terrestrial-type objects being formed, although their survival under tidal evolution is at best unclear. We also see evidence for disrupted fragments with evolved grain populations - this is circumstantial evidence for the formation of planetesimal belts, a phenomenon not seen in runs where fragment-fragment interactions are ignored. In spite of intense dynamical evolution, our population is dominated by massive giant planets and brown dwarfs at large semimajor axis, which direct imaging surveys should, but only rarely, detect. Finally, disc fragmentation is shown to be an efficient manufacturer of free-floating planetary mass objects, and the typical multiplicity of systems formed via gravitational instability will be low.
Planet engulfment and the planetary nebula morphology mystery
NASA Astrophysics Data System (ADS)
Boyle, Laura A.
2018-04-01
This thesis presents an investigation into the galactic population of planetary nebulae (PNe) whose progenitors have evolved through the engulfment of massive planets during the asymptotic giant branch (AGB) phase of their evolution. The objective of this research was to investigate the hypothesis that planet engulfment can aid in explaining the observed non-spherical planetary nebula (PN) population, as a complementary shaping mechanism to the binary hypothesis. This was performed by the design and development of a new research tool, simsplash (SIMulationS for the PLAnet Shaping Hypothesis), which was developed for the specific purpose of conducting, for the first time, a population synthesis of planet engulfment in planetary nebula progenitors. The first step in this investigation involved modelling the tidal evolution of planets orbiting PN progenitor stars to determine the importance of the adopted initial conditions and input physics in the stellar models and their effects on the orbital evolution of star-planet systems. The next step was to determine the probabilities of stars having and engulfing massive planets as a function of stellar mass and metallicity. This was achieved by combining the tidal evolution treatment with both the known exoplanet populations, as well as theoretical planet populations, and the occurrence rates of massive planets. Finally, taking into consideration the results from the analyses described above, a PN population synthesis was performed using the star formation history and metallicity evolution of the galaxy as well as varying forms of the initial mass function and planetary nebula formation constraints. The population of visible PNe in the present-day galaxy was calculated to consist of a total of 16,500±2,200 PNe, of which 240±20 PNe (≃ 1.5%) have evolved from the engulfment of a massive planet on the AGB and 3,300±200 PNe are the result of binary interactions (≃ 20%), translating to an expected non-spherical population of ≃ 21.5% of all PNe currently visible in the galaxy. The overall conclusion from this work is that while planet engulfment can explain a small fraction of the observed population of non-spherical PNe (≃ 7%), the hypothesis is not capable of resolving the mystery of the unexplained population of non-spherical planetary nebula morphologies. This conclusion adds support to the emerging view that not all low-to-intermediate mass stars can form visible PNe.
Sulak, Kenneth J.; Parauka, F; Slack, W. Todd; Ruth, T; Randall, Michael T.; Luke, K; Mette, M. F; Price, M. E
2016-01-01
The Gulf Sturgeon, Acipenser oxyrinchus desotoi, is an anadromous species of Acipenseridae and native to North America. It currently inhabits and spawns in the upper reaches of seven natal rivers along the northern coast of the Gulf of Mexico from the Suwannee River, Florida, to the Pearl River, Louisiana, during spring to autumn. Next to the Alligator Gar (Atractosteus spatula), the Gulf Sturgeon is currently the largest fish species occurring in U.S. Gulf Coast rivers, attaining a length of 2.35 m and weights exceeding 135 kg, but historically attained a substantially larger size. Historically, the spawning populations existed in additional rivers from which the species has been wholly or nearly extirpated, such as the Mobile and Ochlockonee rivers, and possibly the Rio Grande River. Most Gulf Sturgeon populations were decimated by unrestricted commercial fishing between 1895–1910. Subsequently most populations remained unrecovered or extirpated due to continued harvest until the 1970s–1980s, and the construction of dams blocking access to ancestral upriver spawning grounds. Late 20th Century harvest bans and net bans enacted by the several Gulf Coast states have stabilized several populations and enabled the Suwannee River population to rebound substantially and naturally. Hatchery supplementation has not been necessary in this regard to date. Sturgeon are resilient and adaptable fishes with a geological history of 150 million years. Research undertaken since the 1970s has addressed many aspects of Gulf Sturgeon life history, reproduction, migration, population biology, habitat requirements, and other aspects of species biology. However, many knowledge gaps remain, prominently including the life history of early developmental stages in the first year of life. Natural population recovery is evident for the Suwannee River population, but seems promising as well for at least four other populations. The Pascagoula and Pearl River populations face a challenging future due a combination of natural and anthropogenic factors. These two populations, and perhaps the Escambia River population, are particularly vulnerable to periodic mass mortality due to major stochastic events including hurricanes, flooding, hypoxia, and toxic spills. The present manuscript provides a comprehensive synthesis of knowledge regarding the Gulf Sturgeon at the organismal and population levels, identifying knowledge gaps as priorities for future research. Topics not treated in the present synthesis include morphology, internal biology, physiology, and endocrinology. Topics only briefly treated include parasites and diseases, contaminants, and sturgeon aquaculture.
Population Synthesis of Radio and Gamma-ray Pulsars using the Maximum Likelihood Approach
NASA Astrophysics Data System (ADS)
Billman, Caleb; Gonthier, P. L.; Harding, A. K.
2012-01-01
We present the results of a pulsar population synthesis of normal pulsars from the Galactic disk using a maximum likelihood method. We seek to maximize the likelihood of a set of parameters in a Monte Carlo population statistics code to better understand their uncertainties and the confidence region of the model's parameter space. The maximum likelihood method allows for the use of more applicable Poisson statistics in the comparison of distributions of small numbers of detected gamma-ray and radio pulsars. Our code simulates pulsars at birth using Monte Carlo techniques and evolves them to the present assuming initial spatial, kick velocity, magnetic field, and period distributions. Pulsars are spun down to the present and given radio and gamma-ray emission characteristics. We select measured distributions of radio pulsars from the Parkes Multibeam survey and Fermi gamma-ray pulsars to perform a likelihood analysis of the assumed model parameters such as initial period and magnetic field, and radio luminosity. We present the results of a grid search of the parameter space as well as a search for the maximum likelihood using a Markov Chain Monte Carlo method. We express our gratitude for the generous support of the Michigan Space Grant Consortium, of the National Science Foundation (REU and RUI), the NASA Astrophysics Theory and Fundamental Program and the NASA Fermi Guest Investigator Program.
NASA Astrophysics Data System (ADS)
Eldridge, John J.; Stanway, Elizabeth R.
2012-01-01
Young, massive stars dominate the rest-frame ultraviolet (UV) spectra of star-forming galaxies. At high redshifts (z > 2), these rest-frame UV features are shifted into the observed-frame optical and a combination of gravitational lensing, deep spectroscopy and spectral stacking analysis allows the stellar population characteristics of these sources to be investigated. We use our stellar population synthesis code Binary Population and Spectral Synthesis (BPASS) to fit two strong rest-frame UV spectral features in published Lyman-break galaxy spectra, taking into account the effects of binary evolution on the stellar spectrum. In particular, we consider the effects of quasi-homogeneous evolution (arising from the rotational mixing of rapidly rotating stars), metallicity and the relative abundance of carbon and oxygen on the observed strengths of He IIλ1640 Å and C IVλ1548, 1551 Å spectral lines. We find that Lyman-break galaxy spectra at z ˜ 2-3 are best fitted with moderately sub-solar metallicities, and with a depleted carbon-to-oxygen ratio. We also find that the spectra of the lowest metallicity sources are best fitted with model spectra in which the He II emission line is boosted by the inclusion of the effect of massive stars being spun-up during binary mass transfer so these rapidly rotating stars experience quasi-homogeneous evolution.
Aylward, Lesa L.; Morgan, Marsha K.; Arbuckle, Tye E.; Barr, Dana B.; Burns, Carol J.; Alexander, Bruce H.; Hays, Sean M.
2010-01-01
Background Several extensive studies of exposure to 2,4-dichlorophenoxyacetic acid (2,4-D) using urinary concentrations in samples from the general population, farm applicators, and farm family members are now available. Reference doses (RfDs) exist for 2,4-D, and Biomonitoring Equivalents (BEs; concentrations in urine or plasma that are consistent with those RfDs) for 2,4-D have recently been derived and published. Objective We reviewed the available biomonitoring data for 2,4-D from the United States and Canada and compared them with BE values to draw conclusions regarding the margin of safety for 2,4-D exposures within each population group. Data sources Data on urinary 2,4-D excretion in general and target populations from recent published studies are tabulated and the derivation of BE values for 2,4-D summarized. Data synthesis The biomonitoring data indicate margins of safety (ratio of BE value to biomarker concentration) of approximately 200 at the central tendency and 50 at the extremes in the general population. Median exposures for applicators and their family members during periods of use appear to be well within acute exposure guidance values. Conclusions Biomonitoring data from these studies indicate that current exposures to 2,4-D are below applicable exposure guidance values. This review demonstrates the value of biomonitoring data in assessing population exposures in the context of existing risk assessments using the BE approach. Risk managers can use this approach to integrate the available biomonitoring data into an overall assessment of current risk management practices for 2,4-D. PMID:20123603
NASA Astrophysics Data System (ADS)
Anand, Madhu
Nanoparticles have received significant attention because of their unusual characteristics including high surface area to volume ratios. Materials built from nanoparticles possess unique chemical, physical, mechanical and optical properties. Due to these properties, they hold potential in application areas such as catalysts, sensors, semiconductors and optics. At the same time, CO 2 in the form of supercritical fluid or CO2 gas-expanded liquid mixtures has gained significant attention in the area of processing nanostructures. This dissertation focuses on the synthesis and processing of nanoparticles using CO2 tunable solvent systems. Nanoparticle properties depend heavily on their size and, as such, the ability to finely control the size and uniformity of nanoparticles is of utmost importance. Solution based nanoparticle formation techniques are attractive due to their simplicity, but they often result in the synthesis of particles with a wide size range. To address this limitation, a post-synthesis technique has been developed in this dissertation to fractionate polydisperse nanoparticles ( s . = 30%) into monodisperse fractions ( s . = 8%) using tunable physicochemical properties of CO 2 expanded liquids, where CO2 is employed as an antisolvent. This work demonstrates that by controlling the addition of CO2 (pressurization) to an organic dispersion of nanoparticles, the ligand stabilized nanoparticles can be size selectively precipitated within a novel high pressure apparatus that confines the particle precipitation to a specified location on a surface. Unlike current techniques, this CO2 expanded liquid approach provides faster and more efficient particle size separation, reduction in organic solvent usage, and pressure tunable size selection in a single process. To improve our fundamental understanding and to further refine the size separation process, a detailed study has been performed to identify the key parameters enabling size separation of various nanoparticle populations. This study details the influence of various factors on the size separation process, such as the types of nanoparticles, ligand type and solvent type as well as the use of recursive fractionation and the time allowed for settling during each fractionation step. This size selective precipitation technique was also applied to fractionate and separate polydisperse dispersions of CdSe/ZnS semiconductor nanocrystals into very distinct size and color fractions based solely on the pressure tunable solvent properties of CO2 expanded liquids. This size selective precipitation of nanoparticles is achieved by finely tuning the solvent strength of the CO2/organic solvent medium by simply adjusting the applied CO2 pressure. These subtle changes affect the balance between osmotic repulsive and van der Waals attractive forces thereby allowing fractionation of the nanocrystals into multiple narrow size populations. Thermodynamic analysis of nanoparticle size selective fractionation was performed to develop a theoretical model based on the thermodynamic properties of gas expanded liquids. We have used the general phenomenon of nanoparticle precipitation with CO2 expanded liquids to create dodecanethiol stabilized gold nanoparticle thin films. This method utilizes CO2 as an anti-solvent for low defect, wide area gold nanoparticle film formation employing monodisperse gold nanoparticles. Dodecanethiol stabilized gold particles are precipitated from hexane by controllably expanding the solution with carbon dioxide. Subsequent addition of carbon dioxide as a dense supercritical fluid then provides for removal of the organic solvent while avoiding the dewetting effects common to evaporating solvents. Unfortunately, the use of carbon dioxide as a neat solvent in nanoparticles synthesis and processing is limited by the very poor solvent strength of dense phase CO2. As a result, most current techniques employed to synthesize and disperse nanoparticles in neat carbon dioxide require the use of environmentally persistent fluorinated compounds as metal precursors and/or stabilizing ligands. This dissertation presents the first report of the simultaneous synthesis and stabilization of metallic nanoparticles in carbon dioxide solvent without the use of any fluorinated compounds thereby further enabling the use of CO 2 as a green solvent medium in nanomaterials synthesis and processing.
NASA Astrophysics Data System (ADS)
Trupp, Leandro; Laurella, Sergio L.; Tettamanzi, M. Cristina; Barja, Beatriz C.; Bruttomesso, Andrea C.
2018-04-01
Herein we describe the synthesis and conformational analysis of a Tröger's base diformanilide whose distinctive NMR spectra was fully assigned via DFT calculations. The complexity of the spectra originated by the presence of three conformers in equilibrium shows that the nuclei in each side of the molecule are sensitive to the configuration not only of the closest formamide moiety but also of the farthest one, due to long-range anisotropic effects. The temperature and the solvent polarity influence were analyzed to determine the different conformer populations and the corresponding rotational activation parameters.
Spontaneous and controlled-diameter synthesis of single-walled and few-walled carbon nanotubes
NASA Astrophysics Data System (ADS)
Inoue, Shuhei; Lojindarat, Supanat; Kawamoto, Takahiro; Matsumura, Yukihiko; Charinpanitkul, Tawatchai
2018-05-01
In this study, we explored the spontaneous and controlled-diameter growth of carbon nanotubes. We evaluated the effects of catalyst density, reduction time, and a number of catalyst coating on the substrate (for multi-walled carbon nanotubes) on the diameter of single-walled carbon nanotubes and the number of layers in few-walled carbon nanotubes. Increasing the catalyst density and reduction time increased the diameters of the carbon nanotubes, with the average diameter increasing from 1.05 nm to 1.86 nm for single-walled carbon nanotubes. Finally, we succeeded in synthesizing a significant double-walled carbon nanotube population of 24%.
Campbell, Jonathan D; Zerzan, Judy; Garrison, Louis P; Libby, Anne M
2013-04-01
Comparative-effectiveness research (CER) at the population level is missing standardized approaches to quantify and weigh interventions in terms of their clinical risks, benefits, and uncertainty. We proposed an adapted CER framework for population decision making, provided example displays of the outputs, and discussed the implications for population decision makers. Building on decision-analytical modeling but excluding cost, we proposed a 2-step approach to CER that explicitly compared interventions in terms of clinical risks and benefits and linked this evidence to the quality-adjusted life year (QALY). The first step was a traditional intervention-specific evidence synthesis of risks and benefits. The second step was a decision-analytical model to simulate intervention-specific progression of disease over an appropriate time. The output was the ability to compare and quantitatively link clinical outcomes with QALYs. The outputs from these CER models include clinical risks, benefits, and QALYs over flexible and relevant time horizons. This approach yields an explicit, structured, and consistent quantitative framework to weigh all relevant clinical measures. Population decision makers can use this modeling framework and QALYs to aid in their judgment of the individual and collective risks and benefits of the alternatives over time. Future research should study effective communication of these domains for stakeholders. Copyright © 2013 Elsevier HS Journals, Inc. All rights reserved.
Identification of Four Novel Loci in Asthma in European American and African American Populations
Almoguera, Berta; Vazquez, Lyam; Mentch, Frank; Connolly, John; Pacheco, Jennifer A.; Sundaresan, Agnes S.; Peissig, Peggy L.; Linneman, James G.; McCarty, Catherine A.; Crosslin, David; Carrell, David S.; Lingren, Todd; Namjou-Khales, Bahram; Harley, John B.; Larson, Eric; Jarvik, Gail P.; Brilliant, Murray; Williams, Marc S.; Kullo, Iftikhar J.; Hysinger, Erik B.; Hakonarson, Hakon
2017-01-01
Rationale: Despite significant advances in knowledge of the genetic architecture of asthma, specific contributors to the variability in the burden between populations remain uncovered. Objectives: To identify additional genetic susceptibility factors of asthma in European American and African American populations. Methods: A phenotyping algorithm mining electronic medical records was developed and validated to recruit cases with asthma and control subjects from the Electronic Medical Records and Genomics network. Genome-wide association analyses were performed in pediatric and adult asthma cases and control subjects with European American and African American ancestry followed by metaanalysis. Nominally significant results were reanalyzed conditioning on allergy status. Measurements and Main Results: The validation of the algorithm yielded an average of 95.8% positive predictive values for both cases and control subjects. The algorithm accrued 21,644 subjects (65.83% European American and 34.17% African American). We identified four novel population-specific associations with asthma after metaanalyses: loci 6p21.31, 9p21.2, and 10q21.3 in the European American population, and the PTGES gene in African Americans. TEK at 9p21.2, which encodes TIE2, has been shown to be involved in remodeling the airway wall in asthma, and the association remained significant after conditioning by allergy. PTGES, which encodes the prostaglandin E synthase, has also been linked to asthma, where deficient prostaglandin E2 synthesis has been associated with airway remodeling. Conclusions: This study adds to understanding of the genetic architecture of asthma in European Americans and African Americans and reinforces the need to study populations of diverse ethnic backgrounds to identify shared and unique genetic predictors of asthma. PMID:27611488
Hindrikson, Maris; Remm, Jaanus; Pilot, Malgorzata; Godinho, Raquel; Stronen, Astrid Vik; Baltrūnaité, Laima; Czarnomska, Sylwia D; Leonard, Jennifer A; Randi, Ettore; Nowak, Carsten; Åkesson, Mikael; López-Bao, José Vicente; Álvares, Francisco; Llaneza, Luis; Echegaray, Jorge; Vilà, Carles; Ozolins, Janis; Rungis, Dainis; Aspi, Jouni; Paule, Ladislav; Skrbinšek, Tomaž; Saarma, Urmas
2017-08-01
The grey wolf (Canis lupus) is an iconic large carnivore that has increasingly been recognized as an apex predator with intrinsic value and a keystone species. However, wolves have also long represented a primary source of human-carnivore conflict, which has led to long-term persecution of wolves, resulting in a significant decrease in their numbers, genetic diversity and gene flow between populations. For more effective protection and management of wolf populations in Europe, robust scientific evidence is crucial. This review serves as an analytical summary of the main findings from wolf population genetic studies in Europe, covering major studies from the 'pre-genomic era' and the first insights of the 'genomics era'. We analyse, summarize and discuss findings derived from analyses of three compartments of the mammalian genome with different inheritance modes: maternal (mitochondrial DNA), paternal (Y chromosome) and biparental [autosomal microsatellites and single nucleotide polymorphisms (SNPs)]. To describe large-scale trends and patterns of genetic variation in European wolf populations, we conducted a meta-analysis based on the results of previous microsatellite studies and also included new data, covering all 19 European countries for which wolf genetic information is available: Norway, Sweden, Finland, Estonia, Latvia, Lithuania, Poland, Czech Republic, Slovakia, Germany, Belarus, Russia, Italy, Croatia, Bulgaria, Bosnia and Herzegovina, Greece, Spain and Portugal. We compared different indices of genetic diversity in wolf populations and found a significant spatial trend in heterozygosity across Europe from south-west (lowest genetic diversity) to north-east (highest). The range of spatial autocorrelation calculated on the basis of three characteristics of genetic diversity was 650-850 km, suggesting that the genetic diversity of a given wolf population can be influenced by populations up to 850 km away. As an important outcome of this synthesis, we discuss the most pressing issues threatening wolf populations in Europe, highlight important gaps in current knowledge, suggest solutions to overcome these limitations, and provide recommendations for science-based wolf conservation and management at regional and Europe-wide scales. © 2016 Cambridge Philosophical Society.
ERIC Educational Resources Information Center
Carabajal, Ivan G.; Marshall, Anita M.; Atchison, Christopher L.
2017-01-01
People with disabilities make up the largest minority population in the U.S. yet remain sorely underrepresented in scientific disciplines that require components of field-based training such as the geosciences. This paper provides a critical analysis of broadening participation within geoscience education literature through the use of accessible…
Culturally Relevant Pedagogy for Immigrant Children and English Language Learners
ERIC Educational Resources Information Center
Lee, Jin Sook
2010-01-01
The goal of this chapter is to provide a conceptual review of culturally relevant pedagogy (CRP) and a synthesis of research that documents its application to immigrant children and English language learners (ELLs). First, the significance and relevance of CRP are framed in the context of today's student population and the growing gaps in academic…
Conservation and management of eastern big-eared bats: a symposium
Susan C. Loeb; Michael J. Lacki; Darren A. Miller
2011-01-01
Big-eared bats (genus Corynorhinus) in the Eastern United States are species of special conservation concern. These species are at risk due to many factors, including lack of knowledge about their basic biology, population numbers or trends, and distribution. This volume contains five synthesis papers on the status, ecology, and conservation of eastern big-eared bats...
ERIC Educational Resources Information Center
Mickelson, Roslyn Arlin
2016-01-01
Some sixty years after the 1954 "Brown" decision declared separate schooling inherently unequal, America's student population is much larger and more demographically diverse. For many decades court mandated desegregation plans were implemented, but today public schools are again largely segregated by race, ethnicity, and family…
Robert E. Means
2011-01-01
Lower treeline limber pine woodlands have received little attention in peer-reviewed literature and in management strategies. These ecologically distinct systems are thought to be seed repositories between discontinuous populations in the northern and central Rocky Mountains, serving as seed sources for bird dispersal between distinct mountain ranges. Their position on...
Goubert, C; Minard, G; Vieira, C; Boulesteix, M
2016-01-01
The Asian tiger mosquito Aedes albopictus is currently one of the most threatening invasive species in the world. Native to Southeast Asia, the species has spread throughout the world in the past 30 years and is now present in every continent but Antarctica. Because it was the main vector of recent Dengue and Chikungunya outbreaks, and because of its competency for numerous other viruses and pathogens such as the Zika virus, A. albopictus stands out as a model species for invasive diseases vector studies. A synthesis of the current knowledge about the genetic diversity of A. albopictus is needed, knowing the interplays between the vector, the pathogens, the environment and their epidemiological consequences. Such resources are also valuable for assessing the role of genetic diversity in the invasive success. We review here the large but sometimes dispersed literature about the population genetics of A. albopictus. We first debate about the experimental design of these studies and present an up-to-date assessment of the available molecular markers. We then summarize the main genetic characteristics of natural populations and synthesize the available data regarding the worldwide structuring of the vector. Finally, we pinpoint the gaps that remain to be addressed and suggest possible research directions. PMID:27273325
Pain perception in people with Down syndrome: a synthesis of clinical and experimental research
McGuire, Brian E.; Defrin, Ruth
2015-01-01
People with an intellectual disability experience both acute and chronic pain with at least the same frequency as the general population. However, considerably less is known about the pain perception of people with Down syndrome. In this review paper, we evaluated the available clinical and experimental evidence. Some experimental studies of acute pain have indicated that pain threshold was higher than normal but only when using a reaction time method to measure pain sensitivity. However, when reaction time is not part of the calculation of the pain threshold, pain sensitivity in people with Down syndrome is in fact lower than normal (more sensitive to pain). Clinical studies of chronic pain have shown that people with an intellectual disability experience chronic pain and within that population, people with Down syndrome also experience chronic pain, but the precise prevalence of chronic pain in Down syndrome has yet to be established. Taken together, the literature suggests that people with Down syndrome experience pain, both acute and chronic, with at least the same frequency as the rest of the population. Furthermore, the evidence suggests that although acute pain expression appears to be delayed, once pain is registered, there appears to be a magnified pain response. We conclude by proposing an agenda for future research in this area. PMID:26283936
Calanzani, Natalia; Weller, David; Campbell, Christine
2017-01-01
Introduction The increasing burden of cancer morbidity and mortality has led to the development of national health initiatives to promote earlier cancer diagnosis and improve cancer survival. This protocol describes a systematic review aiming to identify the evidence about such initiatives among the adult population. We will describe their components, stakeholders and target populations, and summarise their outcomes. Methods and analysis We will search databases and websites for peer-reviewed publications and grey literature on national health initiatives in high-income countries as defined by the World Bank. Quantitative, qualitative and mixed-methods studies will be included and assessed for their methodological quality. Study selection, quality assessment and data extraction will be carried out independently by two reviewers. Narrative synthesis will be used to analyse the findings. Ethics and dissemination This systematic review analyses secondary data and ethical approval is not required. Review findings will be helpful to researchers, policy makers, governments and other key stakeholders developing similar initiatives and assessing cancer outcomes. The results will be submitted to a peer-reviewed journal in order to reach a diverse group of healthcare professionals, researchers and policy makers. This systematic review protocol is registered at PROSPERO (CRD42016047233). PMID:28698336
Mobile health clinics in the era of reform.
Hill, Caterina F; Powers, Brian W; Jain, Sachin H; Bennet, Jennifer; Vavasis, Anthony; Oriol, Nancy E
2014-03-01
Despite the role of mobile clinics in delivering care to the full spectrum of at-risk populations, the collective impact of mobile clinics has never been assessed. This study characterizes the scope of the mobile clinic sector and its impact on access, costs, and quality. It explores the role of mobile clinics in the era of delivery reform and expanded insurance coverage. A synthesis of observational data collected through Mobile Health Map and published literature related to mobile clinics. Analysis of data from the Mobile Health Map Project, an online platform that aggregates data on mobile health clinics in the United States, supplemented by a comprehensive literature review. Mobile clinics represent an integral component of the healthcare system that serves vulnerable populations and promotes high-quality care at low cost. There are an estimated 1500 mobile clinics receiving 5 million visits nationwide per year. Mobile clinics improve access for vulnerable populations, bolster prevention and chronic disease management, and reduce costs. Expanded coverage and delivery reform increase opportunities for mobile clinics to partner with hospitals, health systems, and insurers to improve care and lower costs. Mobile clinics have a critical role to play in providing high-quality, low-cost care to vulnerable populations. The postreform environment, with increasing accountability for population health management and expanded access among historically underserved populations, should strengthen the ability for mobile clinics to partner with hospitals, health systems, and payers to improve care and lower costs.
Kinner, Stuart A; Young, Jesse T
2018-06-01
The world prison population is growing at a rate that exceeds the rate of population growth. This issue of Epidemiologic Reviews comprises articles in which researchers summarize what is known about some of the key health issues facing people in prison, particularly in relation to human immunodeficiency virus and other blood-borne viral infections. A key recurring theme is that addressing the health needs of people in prison is important to reducing health inequalities at the population level-that prisoner health is public health. The reviews also highlight some critical evidence gaps, notably the lack of evidence from low- and middle-income countries, and the limited number of longitudinal studies in which health behaviors, health outcomes, or health service experiences after release from prison are documented. Despite growing evidence of the poor health of detained adolescents, none of the included reviews considered this population. Further research on the health of young people who cycle through juvenile detention should be a priority. Despite a rapidly growing literature on the health of people who experience incarceration, some critical health issues remain poorly understood, and there has been insufficient attention devoted to co-occurring health conditions and the consequent need for coordinated care. Key populations in custodial settings remain understudied, limiting capacity to develop targeted, evidence-based responses to their health needs. The quality of many studies is suboptimal, and although rigorous, independent research in correctional settings can be challenging, it is not impossible and is critical to laying the groundwork for evidence-based reform.
de Rooij, Mariëtte; van der Leeden, Marike; Heymans, Martijn W; Holla, Jasmijn F M; Häkkinen, Arja; Lems, Willem F; Roorda, Leo D; Veenhof, Cindy; Sanchez-Ramirez, Diana C; de Vet, Henrica C W; Dekker, Joost
2016-04-01
To systematically summarize the literature on the course of pain in patients with knee osteoarthritis (OA), prognostic factors that predict deterioration of pain, the course of physical functioning, and prognostic factors that predict deterioration of physical functioning in persons with knee OA. A search was conducted in PubMed, CINAHL, Embase, Psych-INFO, and SPORTDiscus up to January 2014. A meta-analysis and a qualitative data synthesis were performed. Of the 58 studies included, 39 were of high quality. High heterogeneity across studies (I(2) >90%) and within study populations (reflected by large SDs of change scores) was found. Therefore, the course of pain and physical functioning was interpreted to be indistinct. We found strong evidence for a number of prognostic factors predicting deterioration in pain (e.g., higher knee pain at baseline, bilateral knee symptoms, and depressive symptoms). We also found strong evidence for a number of prognostic factors predicting deterioration in physical functioning (e.g., worsening in radiographic OA, worsening of knee pain, lower knee extension muscle strength, lower walking speed, and higher comorbidity count). Because of high heterogeneity across studies and within study populations, no conclusions can be drawn with regard to the course of pain and physical functioning. These findings support current research efforts to define subgroups or phenotypes within knee OA populations. Strong evidence was found for knee characteristics, clinical factors, and psychosocial factors as prognostics of deterioration of pain and physical functioning. © 2016, American College of Rheumatology.
Emergent properties of interacting populations of spiking neurons.
Cardanobile, Stefano; Rotter, Stefan
2011-01-01
Dynamic neuronal networks are a key paradigm of increasing importance in brain research, concerned with the functional analysis of biological neuronal networks and, at the same time, with the synthesis of artificial brain-like systems. In this context, neuronal network models serve as mathematical tools to understand the function of brains, but they might as well develop into future tools for enhancing certain functions of our nervous system. Here, we present and discuss our recent achievements in developing multiplicative point processes into a viable mathematical framework for spiking network modeling. The perspective is that the dynamic behavior of these neuronal networks is faithfully reflected by a set of non-linear rate equations, describing all interactions on the population level. These equations are similar in structure to Lotka-Volterra equations, well known by their use in modeling predator-prey relations in population biology, but abundant applications to economic theory have also been described. We present a number of biologically relevant examples for spiking network function, which can be studied with the help of the aforementioned correspondence between spike trains and specific systems of non-linear coupled ordinary differential equations. We claim that, enabled by the use of multiplicative point processes, we can make essential contributions to a more thorough understanding of the dynamical properties of interacting neuronal populations.
Transcriptomic responses to high water temperature in two species of Pacific salmon
Jeffries, Ken M; Hinch, Scott G; Sierocinski, Thomas; Pavlidis, Paul; Miller, Kristi M
2014-01-01
Characterizing the cellular stress response (CSR) of species at ecologically relevant temperatures is useful for determining whether populations and species can successfully respond to current climatic extremes and future warming. In this study, populations of wild-caught adult pink (Oncorhynchus gorbuscha) and sockeye (Oncorhynchus nerka) salmon from the Fraser River, British Columbia, Canada, were experimentally treated to ecologically relevant ‘cool’ or ‘warm’ water temperatures to uncover common transcriptomic responses to elevated water temperature in non-lethally sampled gill tissue. We detected the differential expression of 49 microarray features (29 unique annotated genes and one gene with unknown function) associated with protein folding, protein synthesis, metabolism, oxidative stress and ion transport that were common between populations and species of Pacific salmon held at 19°C compared with fish held at a cooler temperature (13 or 14°C). There was higher mortality in fish held at 19°C, which suggests a possible relationship between a temperature-induced CSR and mortality in these species. Our results suggest that frequently encountered water temperatures ≥19°C, which are capable of inducing a common CSR across species and populations, may increase risk of upstream spawning migration failure for pink and sockeye salmon. PMID:24567748
Emergent Properties of Interacting Populations of Spiking Neurons
Cardanobile, Stefano; Rotter, Stefan
2011-01-01
Dynamic neuronal networks are a key paradigm of increasing importance in brain research, concerned with the functional analysis of biological neuronal networks and, at the same time, with the synthesis of artificial brain-like systems. In this context, neuronal network models serve as mathematical tools to understand the function of brains, but they might as well develop into future tools for enhancing certain functions of our nervous system. Here, we present and discuss our recent achievements in developing multiplicative point processes into a viable mathematical framework for spiking network modeling. The perspective is that the dynamic behavior of these neuronal networks is faithfully reflected by a set of non-linear rate equations, describing all interactions on the population level. These equations are similar in structure to Lotka-Volterra equations, well known by their use in modeling predator-prey relations in population biology, but abundant applications to economic theory have also been described. We present a number of biologically relevant examples for spiking network function, which can be studied with the help of the aforementioned correspondence between spike trains and specific systems of non-linear coupled ordinary differential equations. We claim that, enabled by the use of multiplicative point processes, we can make essential contributions to a more thorough understanding of the dynamical properties of interacting neuronal populations. PMID:22207844
DSP Synthesis Algorithm for Generating Florida Scrub Jay Calls
NASA Technical Reports Server (NTRS)
Lane, John; Pittman, Tyler
2017-01-01
A prototype digital signal processing (DSP) algorithm has been developed to approximate Florida scrub jay calls. The Florida scrub jay (Aphelocoma coerulescens), believed to have been in existence for 2 million years, living only in Florida, has a complicated social system that is evident by examining the spectrograms of its calls. Audio data was acquired at the Helen and Allan Cruickshank Sanctuary, Rockledge, Florida during the 2016 mating season using three digital recorders sampling at 44.1 kHz. The synthesis algorithm is a first step at developing a robust identification and call analysis algorithm. Since the Florida scrub jay is severely threatened by loss of habitat, it is important to develop effective methods to monitor their threatened population using autonomous means.
Zeng, Dehong; Yang, Ying; Yang, Feng; Guo, Fangmin; Yang, Senjie; Liu, Baijun; Hao, Shijie; Ren, Yang
2017-08-24
Hexagonal NiO/mesoporous carbon nanodisks (NiO/MCN) are facilely and controllably synthesized via constructing nickel-zinc trimesic acid heterobimetallic metal-organic framework (HMOF) disks before pyrolysis at 910 °C. Tailoring the Ni/(Zn + Ni) feed ratio and the reaction time during the HMOF synthesis creates a well-defined hexagonal carbon nanodisk with properly populated NiO nanocrystals while maintaining high porosity and conductivity. Such an elaborately fabricated NiO/MCN is highly stable, and exhibits the largest specific capacitance of 261 F g -1 and the highest specific activity factor of 1.93 s -1 g -1 of any composite nanodisk during the capacitive test and 4-nitrophenol reduction, respectively.
Direct observation of frequency modulated transcription in single cells using light activation
Larson, Daniel R; Fritzsch, Christoph; Sun, Liang; Meng, Xiuhau; Lawrence, David S; Singer, Robert H
2013-01-01
Single-cell analysis has revealed that transcription is dynamic and stochastic, but tools are lacking that can determine the mechanism operating at a single gene. Here we utilize single-molecule observations of RNA in fixed and living cells to develop a single-cell model of steroid-receptor mediated gene activation. We determine that steroids drive mRNA synthesis by frequency modulation of transcription. This digital behavior in single cells gives rise to the well-known analog dose response across the population. To test this model, we developed a light-activation technology to turn on a single steroid-responsive gene and follow dynamic synthesis of RNA from the activated locus. DOI: http://dx.doi.org/10.7554/eLife.00750.001 PMID:24069527
Carbon dioxide hydrogenation to aromatic hydrocarbons by using an iron/iron oxide nanocatalyst.
Wang, Hongwang; Hodgson, Jim; Shrestha, Tej B; Thapa, Prem S; Moore, David; Wu, Xiaorong; Ikenberry, Myles; Troyer, Deryl L; Wang, Donghai; Hohn, Keith L; Bossmann, Stefan H
2014-01-01
The quest for renewable and cleaner energy sources to meet the rapid population and economic growth is more urgent than ever before. Being the most abundant carbon source in the atmosphere of Earth, CO2 can be used as an inexpensive C1 building block in the synthesis of aromatic fuels for internal combustion engines. We designed a process capable of synthesizing benzene, toluene, xylenes and mesitylene from CO2 and H2 at modest temperatures (T = 380 to 540 °C) employing Fe/Fe3O4 nanoparticles as catalyst. The synthesis of the catalyst and the mechanism of CO2-hydrogenation will be discussed, as well as further applications of Fe/Fe3O4 nanoparticles in catalysis.
An Alu-like RNA promotes cell differentiation and reduces malignancy of human neuroblastoma cells.
Castelnuovo, Manuele; Massone, Sara; Tasso, Roberta; Fiorino, Gloria; Gatti, Monica; Robello, Mauro; Gatta, Elena; Berger, Audrey; Strub, Katharina; Florio, Tullio; Dieci, Giorgio; Cancedda, Ranieri; Pagano, Aldo
2010-10-01
Neuroblastoma (NB) is a pediatric cancer characterized by remarkable cell heterogeneity within the tumor nodules. Here, we demonstrate that the synthesis of a pol III-transcribed noncoding (nc) RNA (NDM29) strongly restricts NB development by promoting cell differentiation, a drop of malignancy processes, and a dramatic reduction of the tumor initiating cell (TIC) fraction in the NB cell population. Notably, the overexpression of NDM29 also confers to malignant NB cells an unpredicted susceptibility to the effects of antiblastic drugs used in NB therapy. Altogether, these results suggest the induction of NDM29 expression as possible treatment to increase cancer cells vulnerability to therapeutics and the measure of its synthesis in NB explants as prognostic factor of this cancer type.
Tricco, Andrea C; Antony, Jesmin; Soobiah, Charlene; Kastner, Monika; MacDonald, Heather; Cogo, Elise; Lillie, Erin; Tran, Judy; Straus, Sharon E
2016-05-01
To describe and compare, through a scoping review, emerging knowledge synthesis methods for integrating qualitative and quantitative evidence in health care, in terms of expertise required, similarities, differences, strengths, limitations, and steps involved in using the methods. Electronic databases (e.g., MEDLINE) were searched, and two reviewers independently selected studies and abstracted data for qualitative analysis. In total, 121 articles reporting seven knowledge synthesis methods (critical interpretive synthesis, integrative review, meta-narrative review, meta-summary, mixed studies review, narrative synthesis, and realist review) were included after screening of 17,962 citations and 1,010 full-text articles. Common similarities among methods related to the entire synthesis process, while common differences related to the research question and eligibility criteria. The most common strength was a comprehensive synthesis providing rich contextual data, whereas the most common weakness was a highly subjective method that was not reproducible. For critical interpretive synthesis, meta-narrative review, meta-summary, and narrative synthesis, guidance was not provided for some steps of the review process. Some of the knowledge synthesis methods provided guidance on all steps, whereas other methods were missing guidance on the synthesis process. Further work is needed to clarify these emerging knowledge synthesis methods. Copyright © 2016 Elsevier Inc. All rights reserved.
Urbanization in Africa: challenges and opportunities for conservation
NASA Astrophysics Data System (ADS)
Güneralp, Burak; Lwasa, Shuaib; Masundire, Hillary; Parnell, Susan; Seto, Karen C.
2017-12-01
Africa, a continent exceptionally rich in biodiversity, is rapidly urbanizing. Africa’s urbanization is manifest in the growth of its megacities as well as that of its smaller towns and cities. The conservation planning and practice will increasingly need to account for direct and indirect impacts of the continent’s urbanization. The objective of our study is to pinpoint the outstanding challenges and opportunities afforded by the growing cities on the continent to the conservation goals and practices. While there have been many studies on the impacts of urbanization and development on conservation in Africa these studies tended to focus on specific issues. Here, we provide a synthesis of this body of work supported by new analysis. Urban areas, growing both in population and in land cover, pose threats to the integrity of the continent’s ecosystems and biodiversity but their growth also create opportunities for conservation. The burgeoning urban populations, especially in Sub-Saharan Africa, increase the strain on already insufficient infrastructure and bring new governance challenges. Yet, Africa’s ecosystems can serve as foundations for green infrastructure to serve the needs of its urban populations while safeguarding fragile biodiversity. Overall, while worsening social problems overshadow the concerns for biodiversity there are also promising initiatives to bring these concerns into the fold to address social, institutional, and ecological challenges that emerge with the continued urbanization of the continent.
NASA Astrophysics Data System (ADS)
Forgan, Duncan; Rice, Ken
2013-07-01
Recently, the gravitational instability (GI) model of giant planet and brown dwarf formation has been revisited and recast into what is often referred to as the `tidal downsizing' hypothesis. The fragmentation of self-gravitating protostellar discs into gravitationally bound embryos - with masses of a few to tens of Jupiter masses, at semimajor axes above 30-40 au - is followed by a combination of grain sedimentation inside the embryo, radial migration towards the central star and tidal disruption of the embryo's upper layers. The properties of the resultant object depends sensitively on the time-scales upon which each process occurs. Therefore, GI followed by tidal downsizing can theoretically produce objects spanning a large mass range, from terrestrial planets to giant planets and brown dwarfs. Whether such objects can be formed in practice, and what proportions of the observed population they would represent, requires a more involved statistical analysis. We present a simple population synthesis model of star and planet formation via GI and tidal downsizing. We couple a semi-analytic model of protostellar disc evolution to analytic calculations of fragmentation, initial embryo mass, grain growth and sedimentation, embryo migration and tidal disruption. While there are key pieces of physics yet to be incorporated, it represents a first step towards a mature statistical model of GI and tidal downsizing as a mode of star and planet formation. We show results from four runs of the population synthesis model, varying the opacity law and the strength of migration, as well as investigating the effect of disc truncation during the fragmentation process. We find that a large fraction of disc fragments are completely destroyed by tidal disruption (typically 40 per cent of the initial population). The tidal downsizing process tends to prohibit low-mass embryos reaching small semimajor axis. The majority of surviving objects are brown dwarfs without solid cores of any kind. Around 40 per cent of surviving objects form solid cores of the order of 5-10 M⊕, and of this group a few do migrate to distances amenable to current exoplanet observations. Over a million disc fragments were simulated in this work, and only one resulted in the formation of a terrestrial planet (i.e. with a core mass of a few Earth masses and no gaseous envelope). These early results suggest that GI followed by tidal downsizing is not the principal mode of planet formation, but remains an excellent means of forming gas giant planets, brown dwarfs and low-mass stars at large semimajor axes.
Brito, A; Chiquette, J; Stabler, S P; Allen, R H; Girard, C L
2015-01-01
Cobalamin (CBL), the biologically active form of vitamin B12, and its analogs, are produced by bacteria only if cobalt supply is adequate. The analogs differ generally by the nucleotide moiety of the molecule. In CBL, 5,6-dimethylbenzimidazole (5,6-DMB) is the base in the nucleotide moiety. The present study aimed to determine if a supplement of 5,6-DMB could increase utilization of dietary cobalt for synthesis of CBL and change ruminal fermentation, nutrient digestibility, omasal flow of nutrients and ruminal protozoa counts. Eight ruminally cannulated multiparous Holstein cows (mean±standard deviation=238±21 days in milk and 736±47 kg of BW) were used in a crossover design. Cows were randomly assigned to a daily supplement of a gelatin capsule containing 1.5 g of 5,6-DMB via the rumen cannula or no supplement. Each period lasted 29 days and consisted of 21 days for treatment adaptation and 8 days for data and samples collection. Five corrinoids, CBL and four cobamides were detected in the total mixed ration and the omasal digesta from both treatments. The dietary supplement of 5,6-DMB increased (P=0.02) apparent ruminal synthesis of CBL from 14.6 to 19.6 (s.e.m. 0.8) mg/day but had no effect (P>0.1) on apparent ruminal synthesis of the four analogs. The supplement of 5,6-DMB had no effect (P>0.1) on milk production and composition, or on protozoal count, ruminal pH and concentrations of volatile fatty acids and ammonia nitrogen in rumen content. The supplement had also no effect (P>0.1) on intake, omasal flow and apparent ruminal digestibility of dry matter, organic matter, NDF, ADF and nitrogenous fractions. Plasma concentration of CBL was not affected by treatments (P=0.98). Providing a preformed part of the CBL molecule, that is, 5,6-DMB, increased by 34% the apparent ruminal synthesis of CBL by ruminal bacteria but had no effect on ruminal fermentation or protozoa count and it was not sufficient to increase plasma concentrations of the vitamin. Even though the efficiency of cobalt utilization for apparent synthesis of CBL was increased from 2.0% to 2.7% by the 5,6-DMB supplement, this improved efficiency was still very low. Further research is needed to identify the factors affecting efficiency of utilization of cobalt for synthesis of CBL by the bacterial populations in rumen.
A Complete VLA Census of the ~7000 Milky Way HII Regions
NASA Astrophysics Data System (ADS)
Armentrout, William Paul; Anderson, Loren; Wenger, Trey V.; Balser, Dana; Bania, Thomas
2018-01-01
How many HII regions are in the Milky Way? Even with the success of recent surveys, we still do not have an adequate answer to this fundamental question. HII regions are the archetypical tracers of Galactic high-mass star formation, but population synthesis modeling indicates that their detection throughout the Galaxy is incomplete, biased toward the most luminous and nearby complexes. Using mid-infrared (MIR) data from the WISE satellite, we identified over 8000 HII regions and candidates, all of which share the characteristic morphology of 12 micron emission enveloping a core of 22 micron emission. Of these, nearly 4000 candidates have no detectable radio continuum emission from Galactic plane surveys and therefore their classification is unknown. These “radio quiet” candidates could represent a significant population of faint HII regions which are ionized by B-stars and/or are especially distant, or they might not be HII regions at all.We present here a survey of radio quiet HII regions in the second and third Galactic quadrants with the Very Large Array. This was the first systematic study of radio quiet HII region candidates. Nearly 60% of the 145 sources observed were detected by the VLA at X-band (10 GHz) to sub-mJy sensitivities. Coupled with their MIR morphologies, detection of continuum strongly indicate they are HII regions. If 60% of radio quiet candidates throughout the Galaxy prove to be HII regions, the number of expected HII regions in the Milky Way would more than double. Constraining the total number of HII regions within the Milky Way will feed back into stellar population synthesis modeling, informing both the high-mass tail of the Galactic star formation rate and the role of high-mass stars in the evolution of the ISM. We estimate there are between 6500 and 7000 HII regions in Milky Way created by a star of type B2 or earlier.
Jimenez-Lopez, Jose C; Zienkiewicz, Agnieszka; Zienkiewicz, Krzysztof; Alché, Juan D; Rodríguez-García, Maria I
2016-03-01
Much of our current knowledge about seed development and differentiation regarding reserves synthesis and accumulation come from monocot (cereals) plants. Studies in dicotyledonous seeds differentiation are limited to a few species and in oleaginous species are even scarcer despite their agronomic and economic importance. We examined the changes accompanying the differentiation of olive endosperm and cotyledon with a focus on protein bodies (PBs) biogenesis during legumin protein synthesis and accumulation, with the aim of getting insights and a better understanding of the PBs' formation process. Cotyledon and endosperm undergo differentiation during seed development, where an asynchronous time-course of protein synthesis, accumulation, and differential PB formation patterns was found in both tissues. At the end of seed maturation, a broad population of PBs, particularly in cotyledon cells, was distinguishable in terms of number per cell and morphometric and cytochemical features. Olive seed development is a tissue-dependent process characterized by differential rates of legumin accumulation and PB formation in the main tissues integrating seed. One of the main features of the impressive differentiation process is the specific formation of a broad group of PBs, particularly in cotyledon cells, which might depend on selective accumulation and packaging of proteins and specific polypeptides into PBs. The nature and availability of the major components detected in the PBs of olive seed are key parameters in order to consider the potential use of this material as a suitable source of carbon and nitrogen for animal or even human use.
The balance sheet for transcription: an analysis of nuclear RNA metabolism in mammalian cells.
Jackson, D A; Pombo, A; Iborra, F
2000-02-01
The control of RNA synthesis from protein-coding genes is fundamental in determining the various cell types of higher eukaryotes. The activation of these genes is driven by promoter complexes, and RNA synthesis is performed by an enzyme mega-complex-the RNA polymerase II holoenzyme. These two complexes are the fundamental components required to initiate gene expression and generate the primary transcripts that, after processing, yield mRNAs that pass to the cytoplasm where protein synthesis occurs. But although this gene expression pathway has been studied intensively, aspects of RNA metabolism remain difficult to comprehend. In particular, it is unclear why >95% of RNA polymerized by polymerase II remains in the nucleus, where it is recycled. To explain this apparent paradox, this review presents a detailed description of nuclear RNA (nRNA) metabolism in mammalian cells. We evaluate the number of active transcription units, discuss the distribution of polymerases on active genes, and assess the efficiency with which the products mature and pass to the cytoplasm. Differences between the behavior of mRNAs on this productive pathway and primary transcripts that never leave the nucleus lead us to propose that these represent distinct populations. We discuss possible roles for nonproductive RNAs and present a model to describe the metabolism of these RNAs in the nuclei of mammalian cells.-Jackson, D. A., Pombo, A., Iborra, F. The balance sheet for transcription: an analysis of nuclear RNA metabolism in mammalian cells.
Missouri River Scaphirhynchus albus (pallid sturgeon) effects analysis—Integrative report 2016
Jacobson, Robert B.; Annis, Mandy L.; Colvin, Michael E.; James, Daniel A.; Welker, Timothy L.; Parsley, Michael J.
2016-07-15
The Missouri River Pallid Sturgeon Effects Analysis was designed to carry out three components of an assessment of how Missouri River management has affected, and will affect, population dynamics of endangered Scaphirhynchus albus (pallid sturgeon): (1) collection of reliable scientific information, (2) critical assessment and synthesis of available data and analyses, and (3) analysis of the effects of actions on listed species and their habitats. This report is a synthesis of the three components emphasizing development of lines of evidence relating potential future management actions to pallid sturgeon population dynamics. We address 21 working management hypotheses that emerged from an expert opinion-based filtering process.The ability to quantify linkages from abiotic changes to pallid sturgeon population dynamics is compromised by fundamental information gaps. Although a substantial foundation of pallid sturgeon science has been developed during the past 20 years, our efforts attempt to push beyond that understanding to provide predictions of how future management actions may affect pallid sturgeon responses. For some of the 21 hypotheses, lines of evidence are limited to theoretical deduction, inference from sparse empirical datasets, or expert opinion. Useful simulation models have been developed to predict the effects of management actions on survival of drifting pallid sturgeon free embryos in the Yellowstone and Upper Missouri River complex (hereafter referred to as the “upper river”), and to assess the effects of flow and channel reconfigurations on habitat availability in the Lower Missouri River, tributaries, and Mississippi River downstream of Gavins Point Dam (hereafter referred to as the “lower river”). A population model also has been developed that can be used to assess sensitivity of the population to survival of specific life stages, assess some hypotheses related to stocking decisions, and explore a limited number of management scenarios.Consideration of lines of evidence for each of the 21 hypotheses includes a discussion of how the degree of uncertainty and risk associated with each hypothesis may guide science and implementation strategies. Implementation strategies include full implementation in the field, limited implementations as field-scale experiments, or (in the case of greatest uncertainty) implementation as learning actions, including research and opportunistic experiments or field-based gradient studies. Given the substantive uncertainties associated with pallid sturgeon population dynamics and the need to continually assimilate and assess new information, we proposed that an Effects Analysis-like process should be considered an integral part of ongoing Missouri River adaptive management.
Proteomic Analysis of Altered Extracellular Matrix Turnover in Bleomycin-induced Pulmonary Fibrosis
Decaris, Martin L.; Gatmaitan, Michelle; FlorCruz, Simplicia; Luo, Flora; Li, Kelvin; Holmes, William E.; Hellerstein, Marc K.; Turner, Scott M.; Emson, Claire L.
2014-01-01
Fibrotic disease is characterized by the pathological accumulation of extracellular matrix (ECM) proteins. Surprisingly, very little is known about the synthesis and degradation rates of the many proteins and proteoglycans that constitute healthy or pathological extracellular matrix. A comprehensive understanding of altered ECM protein synthesis and degradation during the onset and progression of fibrotic disease would be immensely valuable. We have developed a dynamic proteomics platform that quantifies the fractional synthesis rates of large numbers of proteins via stable isotope labeling and LC/MS-based mass isotopomer analysis. Here, we present the first broad analysis of ECM protein kinetics during the onset of experimental pulmonary fibrosis. Mice were labeled with heavy water for up to 21 days following the induction of lung fibrosis with bleomycin. Lung tissue was subjected to sequential protein extraction to fractionate cellular, guanidine-soluble ECM proteins and residual insoluble ECM proteins. Fractional synthesis rates were calculated for 34 ECM proteins or protein subunits, including collagens, proteoglycans, and microfibrillar proteins. Overall, fractional synthesis rates of guanidine-soluble ECM proteins were faster than those of insoluble ECM proteins, suggesting that the insoluble fraction reflected older, more mature matrix components. This was confirmed through the quantitation of pyridinoline cross-links in each protein fraction. In fibrotic lung tissue, there was a significant increase in the fractional synthesis of unique sets of matrix proteins during early (pre-1 week) and late (post-1 week) fibrotic response. Furthermore, we isolated fast turnover subpopulations of several ECM proteins (e.g. type I collagen) based on guanidine solubility, allowing for accelerated detection of increased synthesis of typically slow-turnover protein populations. This establishes the presence of multiple kinetic pools of pulmonary collagen in vivo with altered turnover rates during evolving fibrosis. These data demonstrate the utility of dynamic proteomics in analyzing changes in ECM protein turnover associated with the onset and progression of fibrotic disease. PMID:24741116
A review of an updated synthesis of noise/annoyance relationships
NASA Technical Reports Server (NTRS)
Fields, James M.
1994-01-01
This report evaluates the evidence supporting the 'dosage-effect relationship for the prevalence of annoyance due to general transportation noise' that was originally presented in 1978 and more recently updated in 1991. The synthesis methods and many of the constituent studies' reports are examined. The weaknesses of the synthesis are identified and found to be partly due to the synthesis methodology, but fundamentally to the lack of comparability in the constituent studies' methodologies and reporting procedures. Several suggested improvements to survey, analysis, and synthesis techniques are proposed.
Spanish-Language Consumer Health Information Technology Interventions: A Systematic Review.
Chaet, Alexis V; Morshedi, Bijan; Wells, Kristen J; Barnes, Laura E; Valdez, Rupa
2016-08-10
As consumer health information technology (IT) becomes more thoroughly integrated into patient care, it is critical that these tools are appropriate for the diverse patient populations whom they are intended to serve. Cultural differences associated with ethnicity are one aspect of diversity that may play a role in user-technology interactions. Our aim was to evaluate the current scope of consumer health IT interventions targeted to the US Spanish-speaking Latino population and to characterize these interventions in terms of technological attributes, health domains, cultural tailoring, and evaluation metrics. A narrative synthesis was conducted of existing Spanish-language consumer health IT interventions indexed within health and computer science databases. Database searches were limited to English-language articles published between January 1990 and September 2015. Studies were included if they detailed an assessment of a patient-centered electronic technology intervention targeting health within the US Spanish-speaking Latino population. Included studies were required to have a majority Latino population sample. The following were extracted from articles: first author's last name, publication year, population characteristics, journal domain, health domain, technology platform and functionality, available languages of intervention, US region, cultural tailoring, intervention delivery location, study design, and evaluation metrics. We included 42 studies in the review. Most of the studies were published between 2009 and 2015 and had a majority percentage of female study participants. The mean age of participants ranged from 15 to 68. Interventions most commonly focused on urban population centers and within the western region of the United States. Of articles specifying a technology domain, computer was found to be most common; however, a fairly even distribution across all technologies was noted. Cancer, diabetes, and child, infant, or maternal health were the most common health domains targeted by consumer health IT interventions. More than half of the interventions were culturally tailored. The most frequently used evaluation metric was behavior/attitude change, followed by usability and knowledge retention. This study characterizes the existing body of research exploring consumer health IT interventions for the US Spanish-speaking Latino population. In doing so, it reveals three primary needs within the field. First, while the increase in studies targeting the Latino population in the last decade is a promising advancement, future research is needed that focuses on Latino subpopulations previously overlooked. Second, preliminary steps have been taken to culturally tailor consumer health IT interventions for the US Spanish-speaking Latino population; however, focus must expand beyond intervention content. Finally, the field should work to promote long-term evaluation of technology efficacy, moving beyond intermediary measures toward measures of health outcomes.
The Swift/UVOT catalogue of NGC 4321 star-forming sources: a case against density wave theory
NASA Astrophysics Data System (ADS)
Ferreras, Ignacio; Cropper, Mark; Kawata, Daisuke; Page, Mat; Hoversten, Erik A.
2012-08-01
We study the star-forming regions in the spiral galaxy NGC 4321 (M100). We take advantage of the spatial resolution (2.5 arcsec full width at half-maximum) of the Swift/Ultraviolet/Optical Telescope camera and the availability of three ultraviolet (UV) passbands in the region 1600 < λ < 3000 Å, in combination with optical and infrared (IR) imaging from Sloan Digital Sky Survey, KPNO/Hα and Spitzer/IRAC, to obtain a catalogue of 787 star-forming regions out to three disc scalelengths. We use a large volume of star formation histories, combined with stellar population synthesis, to determine the properties of the young stellar component and its relationship with the spiral arms. The Hα luminosities of the sources have a strong decreasing radial trend, suggesting more massive star-forming regions in the central part of the galaxy. When segregated with respect to near-UV (NUV)-optical colour, blue sources have a significant excess of flux in the IR at 8 μm, revealing the contribution from polycyclic aromatic hydrocarbons, although the overall reddening of these sources stays below E(B - V) = 0.2 mag. The distribution of distances to the spiral arms is compared for subsamples selected according to Hα luminosity, NUV-optical colour or ages derived from a population synthesis model. An offset would be expected between these subsamples as a function of radius if the pattern speed of the spiral arm were constant - as predicted by classic density wave theory. No significant offsets are found, favouring instead a mechanism where the pattern speed has a radial dependence.
The cosmic merger rate of stellar black hole binaries from the Illustris simulation
NASA Astrophysics Data System (ADS)
Mapelli, Michela; Giacobbo, Nicola; Ripamonti, Emanuele; Spera, Mario
2017-12-01
The cosmic merger rate density of black hole binaries (BHBs) can give us an essential clue to constraining the formation channels of BHBs, in light of current and forthcoming gravitational wave detections. Following a Monte Carlo approach, we couple new population-synthesis models of BHBs with the Illustris cosmological simulation, to study the cosmic history of BHB mergers. We explore six population-synthesis models, varying the prescriptions for supernovae, common envelope and natal kicks. In most considered models, the cosmic BHB merger rate follows the same trend as the cosmic star formation rate. The normalization of the cosmic BHB merger rate strongly depends on the treatment of common envelope and on the distribution of natal kicks. We find that most BHBs merging within LIGO's instrumental horizon come from relatively metal-poor progenitors (<0.2 Z⊙). The total masses of merging BHBs span a large range of values, from ∼6 to ∼82 M⊙. In our fiducial model, merging BHBs consistent with GW150914, GW151226 and GW170104 represent ∼6, 3 and 12 per cent of all BHBs merging within the LIGO horizon, respectively. The heavy systems, like GW150914, come from metal-poor progenitors (<0.15 Z⊙). Most GW150914-like systems merging in the local Universe appear to have formed at high redshift, with a long delay time. In contrast, GW151226-like systems form and merge all the way through the cosmic history, from progenitors with a broad range of metallicities. Future detections will be crucial to put constraints on common envelope, on natal kicks, and on the BHB mass function.
Wanapat, M; Cherdthong, A; Pakdee, P; Wanapat, S
2008-12-01
This experiment was conducted to investigate the effect of lemongrass [Cymbopogon citratus (DC.) Stapf.] powder (LGP) on rumen ecology, rumen microorganisms, and digestibility of nutrients. Four ruminally fistulated crossbred (Brahman native) beef cattle were randomly assigned according to a 4 x 4 Latin square design. The dietary treatments were LGP supplementation at 0, 100, 200, and 300 g/d with urea-treated rice straw (5%) fed to allow ad libitum intake. Digestibilities of DM, ether extract, and NDF were significantly different among treatments and were greatest at 100 g/d of supplementation. However, digestibility of CP was decreased with LGP supplementation (P < 0.05), whereas ruminal NH(3)-N and plasma urea N were decreased with incremental additions of LGP (P < 0.05). Ruminal VFA concentrations were similar among supplementation concentrations (P > 0.05). Total viable bacteria, amylolytic bacteria, and cellulolytic bacteria were significantly different among treatments and were greatest at 100 g/d of supplementation (4.7 x 10(9), 1.7 x 10(7), and 2.0 x 10(9) cfu/mL, respectively). Protozoal populations were significantly decreased by LGP supplementation. In addition, efficiency of rumen microbial N synthesis based on OM truly digested in the rumen was enriched by LGP supplementation, especially at 100 g/d (34.2 g of N/kg of OM truly digested in the rumen). Based on this study, it could be concluded that supplementation of LGP at 100 g/d improved digestibilities of nutrients, rumen microbial population, and microbial protein synthesis efficiency, thus improving rumen ecology in beef cattle.
Zhang, Qian
2012-01-01
Naturalized soil Escherichia coli populations need to resist common soil desiccation stress in order to inhabit soil environments. In this study, four representative soil E. coli strains and one lab strain, MG1655, were tested for desiccation resistance via die-off experiments in sterile quartz sand under a potassium acetate-induced desiccation condition. The desiccation stress caused significantly lower die-off rates of the four soil strains (0.17 to 0.40 day−1) than that of MG1655 (0.85 day−1). Cellular responses, including extracellular polymeric substance (EPS) production, exogenous glycine betaine (GB) uptake, and intracellular compatible organic solute synthesis, were quantified and compared under the desiccation and hydrated control conditions. GB uptake appeared not to be a specific desiccation response, while EPS production showed considerable variability among the E. coli strains. All E. coli strains produced more intracellular trehalose, proline, and glutamine under the desiccation condition than the hydrated control, and only the trehalose concentration exhibited a significant correlation with the desiccation-contributed die-off coefficients (Spearman's ρ = −1.0; P = 0.02). De novo trehalose synthesis was further determined for 15 E. coli strains from both soil and nonsoil sources to determine its prevalence as a specific desiccation response. Most E. coli strains (14/15) synthesized significantly more trehalose under the desiccation condition, and the soil E. coli strains produced more trehalose (106.5 ± 44.9 μmol/mg of protein [mean ± standard deviation]) than the nonsoil reference strains (32.5 ± 10.5 μmol/mg of protein). PMID:22885754
Boag, Alisdair M.; Christie, Michael R.; McLaughlin, Kerry A.; Syme, Harriet M.; Graham, Peter; Catchpole, Brian
2015-01-01
Canine hypoadrenocorticism likely arises from immune-mediated destruction of adrenocortical tissue, leading to glucocorticoid and mineralocorticoid deficiency. In humans with autoimmune Addison’s disease (AAD) or autoimmune polyendocrine syndrome (APS), circulating autoantibodies have been demonstrated against enzymes associated with adrenal steroid synthesis. The current study investigates autoantibodies against steroid synthesis enzymes in dogs with spontaneous hypoadrenocorticism. Coding regions of canine CYP21A2 (21-hydroxylase; 21-OH), CYP17A1 (17-hydroxylase; 17-OH), CYP11A1 (P450 side-chain cleavage enzyme; P450scc) and HSD3B2 (3β hydroxysteroid dehydrogenase; 3βHSD) were amplified, cloned and expressed as 35S-methionine radiolabelled recombinant protein. In a pilot study, serum samples from 20 dogs with hypoadrenocorticism and four unaffected control dogs were screened by radio-immunoprecipitation assay. There was no evidence of reactivity against 21-OH, 17-OH or 3βHSD, but five dogs with hypoadrenocorticism showed immunoreactivity to P450scc compared with controls. Serum samples were subsequently obtained from 213 dogs diagnosed with hypoadrenocorticism and 110 dogs from a hospital control population. Thirty control dogs were randomly selected to establish a threshold for antibody positivity (mean + 3 × standard deviation). Dogs with hypoadrenocorticism were more likely to be P450scc autoantibody positive than hospital controls (24% vs. 1.2%, respectively; p = 0.0016). Sex was significantly associated with the presence of P450scc autoantibodies in the case population, with 30% of females testing positive compared with 17% of males (p = 0.037). Significant associations with breed (p = 0.015) and DLA-type (DQA1*006:01 allele; p = 0.017) were also found. This cross-sectional study indicates that P450scc autoantibodies are present in a proportion of dogs affected with hypoadrenocorticism. PMID:26618927
Boag, Alisdair M; Christie, Michael R; McLaughlin, Kerry A; Syme, Harriet M; Graham, Peter; Catchpole, Brian
2015-01-01
Canine hypoadrenocorticism likely arises from immune-mediated destruction of adrenocortical tissue, leading to glucocorticoid and mineralocorticoid deficiency. In humans with autoimmune Addison's disease (AAD) or autoimmune polyendocrine syndrome (APS), circulating autoantibodies have been demonstrated against enzymes associated with adrenal steroid synthesis. The current study investigates autoantibodies against steroid synthesis enzymes in dogs with spontaneous hypoadrenocorticism. Coding regions of canine CYP21A2 (21-hydroxylase; 21-OH), CYP17A1 (17-hydroxylase; 17-OH), CYP11A1 (P450 side-chain cleavage enzyme; P450scc) and HSD3B2 (3β hydroxysteroid dehydrogenase; 3βHSD) were amplified, cloned and expressed as 35S-methionine radiolabelled recombinant protein. In a pilot study, serum samples from 20 dogs with hypoadrenocorticism and four unaffected control dogs were screened by radio-immunoprecipitation assay. There was no evidence of reactivity against 21-OH, 17-OH or 3βHSD, but five dogs with hypoadrenocorticism showed immunoreactivity to P450scc compared with controls. Serum samples were subsequently obtained from 213 dogs diagnosed with hypoadrenocorticism and 110 dogs from a hospital control population. Thirty control dogs were randomly selected to establish a threshold for antibody positivity (mean + 3 × standard deviation). Dogs with hypoadrenocorticism were more likely to be P450scc autoantibody positive than hospital controls (24% vs. 1.2%, respectively; p = 0.0016). Sex was significantly associated with the presence of P450scc autoantibodies in the case population, with 30% of females testing positive compared with 17% of males (p = 0.037). Significant associations with breed (p = 0.015) and DLA-type (DQA1*006:01 allele; p = 0.017) were also found. This cross-sectional study indicates that P450scc autoantibodies are present in a proportion of dogs affected with hypoadrenocorticism.
Carter, Alexander W; Mandavia, Rishi; Mayer, Erik; Marti, Joachim; Mossialos, Elias; Darzi, Ara
2017-01-01
Introduction Recent avoidable failures in patient care highlight the ongoing need for evidence to support improvements in patient safety. According to the most recent reviews, there is a dearth of economic evidence related to patient safety. These reviews characterise an evidence gap in terms of the scope and quality of evidence available to support resource allocation decisions. This protocol is designed to update and improve on the reviews previously conducted to determine the extent of methodological progress in economic analyses in patient safety. Methods and analysis A broad search strategy with two core themes for original research (excluding opinion pieces and systematic reviews) in ‘patient safety’ and ‘economic analyses’ has been developed. Medline, Econlit and National Health Service Economic Evaluation Database bibliographic databases will be searched from January 2007 using a combination of medical subject headings terms and research-derived search terms (see table 1). The method is informed by previous reviews on this topic, published in 2012. Screening, risk of bias assessment (using the Cochrane collaboration tool) and economic evaluation quality assessment (using the Drummond checklist) will be conducted by two independent reviewers, with arbitration by a third reviewer as needed. Studies with a low risk of bias will be assessed using the Drummond checklist. High-quality economic evaluations are those that score >20/35. A qualitative synthesis of evidence will be performed using a data collection tool to capture the study design(s) employed, population(s), setting(s), disease area(s), intervention(s) and outcome(s) studied. Methodological quality scores will be compared with previous reviews where possible. Effect size(s) and estimate uncertainty will be captured and used in a quantitative synthesis of high-quality evidence, where possible. Ethics and dissemination Formal ethical approval is not required as primary data will not be collected. The results will be disseminated through a peer-reviewed publication, presentations and social media. Trial registration number CRD42017057853. PMID:28821527
[Evaluation of Uruguay's antismoking campaign: progress and challenges at ten years].
Triunfo, Patricia; Harris, Jeffrey; Balsa, Ana
2016-10-01
In 2005, shortly after ratifying the Framework Convention on Tobacco Control (FCTC), Uruguay began an ambitious tobacco control campaign that brought the country to the global forefront in the fight against smoking. The wide range of measures implemented in a relatively short period and the rigorousness with which policies were implemented and enforced have few precedents, even in the most developed countries. This paper presents a synthesis and update of several papers by the authors that evaluate different aspects of the campaign ten years following ratification of the FCTC. In particular, these research studies highlight the campaign's aggregate impact on the drop in prevalence of current tobacco consumption in adult and youth populations, and on decisions by pregnant women to quit smoking (1, 2), as well as the relative impact of tax policies in relation to non-price tobacco control measures. The analyses are based on observational studies (at the population or individual level) that use external (Argentina and Chile) and internal (nonsmokers) control groups. Pending challenges in the design of antismoking policies are also discussed.
NASA Astrophysics Data System (ADS)
Wofford, A.; Charlot, S.; Bruzual, G.; Eldridge, J. J.; Calzetti, D.; Adamo, A.; Cignoni, M.; de Mink, S. E.; Gouliermis, D. A.; Grasha, K.; Grebel, E. K.; Lee, J. C.; Östlin, G.; Smith, L. J.; Ubeda, L.; Zackrisson, E.
2016-04-01
We test the predictions of spectral synthesis models based on seven different massive-star prescriptions against Legacy ExtraGalactic UV Survey (LEGUS) observations of eight young massive clusters in two local galaxies, NGC 1566 and NGC 5253, chosen because predictions of all seven models are available at the published galactic metallicities. The high angular resolution, extensive cluster inventory, and full near-ultraviolet to near-infrared photometric coverage make the LEGUS data set excellent for this study. We account for both stellar and nebular emission in the models and try two different prescriptions for attenuation by dust. From Bayesian fits of model libraries to the observations, we find remarkably low dispersion in the median E(B - V) (˜0.03 mag), stellar masses (˜104 M⊙), and ages (˜1 Myr) derived for individual clusters using different models, although maximum discrepancies in these quantities can reach 0.09 mag and factors of 2.8 and 2.5, respectively. This is for ranges in median properties of 0.05-0.54 mag, 1.8-10 × 104 M⊙, and 1.6-40 Myr spanned by the clusters in our sample. In terms of best fit, the observations are slightly better reproduced by models with interacting binaries and least well reproduced by models with single rotating stars. Our study provides a first quantitative estimate of the accuracies and uncertainties of the most recent spectral synthesis models of young stellar populations, demonstrates the good progress of models in fitting high-quality observations, and highlights the needs for a larger cluster sample and more extensive tests of the model parameter space.
Valentijn, Pim P; Biermann, Claus; Bruijnzeels, Marc A
2016-08-02
Integrated care services are considered a vital strategy for improving the Triple Aim values for people with chronic kidney disease. However, a solid scholarly explanation of how to develop, implement and evaluate such value-based integrated renal care services is limited. The aim of this study was to develop a framework to identify the strategies and outcomes for the implementation of value-based integrated renal care. First, the theoretical foundations of the Rainbow Model of Integrated Care and the Triple Aim were united into one overarching framework through an iterative process of key-informant consultations. Second, a rapid review approach was conducted to identify the published research on integrated renal care, and the Cochrane Library, Medline, Scopus, and Business Source Premier databases were searched for pertinent articles published between 2000 and 2015. Based on the framework, a coding schema was developed to synthesis the included articles. The overarching framework distinguishes the integrated care domains: 1) type of integration, 2) enablers of integration and the interrelated outcome domains, 3) experience of care, 4) population health and 5) costs. The literature synthesis indicated that integrated renal care implementation strategies have particularly focused on micro clinical processes and physical outcomes, while little emphasis has been placed on meso organisational as well as macro system integration processes. In addition, evidence regarding patients' perceived outcomes and economic outcomes has been weak. These results underscore that the future challenge for researchers is to explore which integrated care implementation strategies achieve better health and improved experience of care at a lower cost within a specific context. For this purpose, this study's framework and evidence synthesis have set a developmental agenda for both integrated renal care practice and research. Accordingly, we plan further work to develop an implementation model for value-based integrated renal services.
Nguyen, Thao M; Pettibone, John M; Gigault, Julien; Hackley, Vincent A
2016-03-01
The control of gold nanorod (GNR) solution-based syntheses has been hindered in part by the inability to examine and control the conversion of precursor seed populations to anisotropic materials, which have resulted in low yields of desired products and limited their commercial viability. The advantages offered by tandem separation and characterization methods utilizing asymmetric-flow field flow fractionation (A4F) are principally achieved as a result of their non-disruptive nature (minimizing artefacts), fast throughput, and in-situ analysis. With hyphenated A4F methods, resolved populations of seeds and secondary products, up to long aspect ratio rods, have been achieved and exemplify progress towards elucidating mechanistic aspects of formation and thus rational design. While there have been previously reported studies on A4F separation of GNRs, to our knowledge, this is the first published investigation of in situ GNR growth, separation, and characterization based on A4F, where its utilization in this capacity goes beyond traditional separation analysis. By using hydroquinone as the reducing agent, the conversion of the initial seed population to a distribution of products, including the GNRs, could be monitored in real time using A4F hyphenated with a diode array detector. Transmission electron microscopy confirms that the number of peaks observed during fractionation corresponds with size and shape dispersity. This proof-of-principle study introduces A4F as a technique that establishes a foundation for future mechanistic studies on the growth of GNRs from gold seeds, including conversion of the seed population to initial products, a topic highly relevant to advancing progress in nanomanufacturing.
Leppanen, Jenni; Ng, Kah Wee; Kim, Youl-Ri; Tchanturia, Kate; Treasure, Janet
2018-01-01
Heightened threat sensitivity is a transdiagnostic feature in several psychiatric disorders. The neuropeptide oxytocin has been shown to reduce fear related behaviours and facilitated fear extinction in animals. These findings have led to increasing interest to explore the effects of intranasal oxytocin on threat processing in humans. The review included 26 studies (N = 1173), nine of which included clinical populations (N = 234). The clinical groups included were people with borderline personality disorder (BPD), anorexia nervosa, bulimia nervosa, depression, anxiety, and alcohol dependence disorder. We examined the effects of a single dose of intranasal oxytocin on startle response, attentional responses, and behavioural responses to threat. A single dose of intranasal oxytocin significantly increased the physiological startle response to threat in healthy people with a small effect size. However, oxytocin did not have significant effects on attentional bias towards social or disorder-specific threat, fixation towards threatening stimuli among healthy or clinical populations, or on threat related behavioural approach or avoidance responses. No studies investigated the effects of oxytocin on the startle response to threat among clinical populations. Additionally, only one of the reviewed studies had sufficient power to detect at least a moderate effect of oxytocin according to our criterion. The synthesis of literature suggest that oxytocin may influence the salience of threatening stimuli among healthy individuals, increasing the startle response to threat. It would be of interest to investigate the effects of oxytocin on the startle response to threat among clinical populations. Copyright © 2017 Elsevier B.V. All rights reserved.
Baker, Phillip; Hawkes, Corinna; Wingrove, Kate; Demaio, Alessandro Rhyl; Parkhurst, Justin; Thow, Anne Marie; Walls, Helen
2018-01-01
Generating country-level political commitment will be critical to driving forward action throughout the United Nations Decade of Action on Nutrition (2016-2025). In this review of the empirical nutrition policy literature, we ask: what factors generate, sustain and constrain political commitment for nutrition, how and under what circumstances? Our aim is to inform strategic 'commitment-building' actions. We adopted a framework synthesis method and realist review protocol. An initial framework was derived from relevant theory and then populated with empirical evidence to test and modify it. Five steps were undertaken: initial theoretical framework development; search for relevant empirical literature; study selection and quality appraisal; data extraction, analysis and synthesis and framework modification. 75 studies were included. We identified 18 factors that drive commitment, organised into five categories: actors; institutions; political and societal contexts; knowledge, evidence and framing; and, capacities and resources. Irrespective of country-context, effective nutrition actor networks, strong leadership, civil society mobilisation, supportive political administrations, societal change and focusing events, cohesive and resonant framing, and robust data systems and available evidence were commitment drivers. Low-income and middle-income country studies also frequently reported international actors, empowered institutions, vertical coordination and capacities and resources. In upper-middle-income and high-income country studies, private sector interference frequently undermined commitment. Political commitment is not something that simply exists or emerges accidentally; it can be created and strengthened over time through strategic action. Successfully generating commitment will likely require a core set of actions with some context-dependent adaptations. Ultimately, it will necessitate strategic actions by cohesive, resourced and strongly led nutrition actor networks that are responsive to the multifactorial, multilevel and dynamic political systems in which they operate and attempt to influence. Accelerating the formation and effectiveness of such networks over the Nutrition Decade should be a core task for all actors involved.
Engler, Kim; Lènàrt, Andras; Lessard, David; Toupin, Isabelle; Lebouché, Bertrand
2018-05-02
Suboptimal adherence to antiretroviral therapy (ART) remains common. Patient-centered tools are needed to comprehensively assess adherence barriers in HIV clinical practice. Thus, we conducted a research synthesis to produce a conceptual framework for a new patient-reported outcome measure (PRO) for use in routine HIV care in Canada and France. A PRO's conceptual framework graphically represents the concepts to be measured and the potential relationships between them. Towards ensuring the framework's relevance to the target populations' concerns, qualitative studies with HIV-positive adults on barriers to ART adherence in developed countries were synthesized with thematic analysis, attending to the cross-study prevalence and interrelationships of barrier themes. In March 2016, searches within Medline, PsychINFO, and Embase produced 5,284 records. Two reviewers determined the final sample (n = 41). Analysis generated three levels of ART adherence barrier themes. Twenty Level 2 themes and their component subthemes (Level 3) were organized into 6 higher-order themes (Level 1): Cognitive and emotional aspects (100% of studies contributing content -prevalence), Lifestyle factors (95%), Social and material context (95%), Characteristics of ART (90%), Health experience and state (73%), and Healthcare services and system (66%). As to interrelationships, study authors articulated relationships between all higher-order themes (Level 3). Linkages between Level 2 barrier themes showed great variability, from 21% to 95%. Overall, this synthesis contributes an exceptionally detailed conceptual framework and report of ART adherence barriers, applicable to a wide range of PLHIV. It suggests that a key to understanding many barriers is through their interconnections. It also identifies gaps in barrier research. Concerning the new PRO's development, comprehensiveness will need to be weighed against other concerns (e.g., respondent burden) and the provision of barrier-specific guidance for clinically addressing its scores seems essential.
The genetics of cholesteatoma. A systematic review using narrative synthesis.
Jennings, B A; Prinsley, P; Philpott, C; Willis, G; Bhutta, M F
2018-02-01
A cholesteatoma is a mass of keratinising epithelium in the middle ear. It is a rare disorder that is associated with significant morbidity, and its causative risk factors are poorly understood; on a global scale, up to a million people are affected by this each year. We have conducted a systematic literature review to identify reports about the heritability of cholesteatoma or any constitutional genetic factors that may be associated with its aetiology. A systematic search of MEDLINE (EBSCO) and two databases of curated genetic research (OMIM and Phenopedia) was conducted. The participants and populations of interest for this review were people treated for cholesteatoma and their family members. The studies of interest reported evidence of heritability for the trait, or any association with congenital syndromes and particular genetic variants. The searches identified 449 unique studies, of which 35 were included in the final narrative synthesis. A narrative synthesis was conducted, and data were tabulated to record characteristics, including study design, genetic data and author conclusions. Most of the studies identified in the literature search, and described here, are case reports and so represent the lowest level of evidence. In a few case reports, congenital and acquired cholesteatomas have been shown to segregate within families in the pattern typical of a monogenic or oligogenic disorder with incomplete penetrance. Evidence from syndromic cases could suggest that genes controlling ear morphology may be risk factors for cholesteatoma formation. This is the first systematic review about the genetics of cholesteatoma, and we have identified a small body of relevant literature that provides evidence of a heritable component for its aetiology. Cholesteatoma is a complex and heterogeneous clinical phenotype, and it is often associated with chronic otitis media and with some rare congenital syndromes known to affect ear morphology and related pathologies. © 2017 The Authors. Clinical Otolaryngology Published by John Wiley & Sons Ltd.
Baker, Phillip; Hawkes, Corinna; Wingrove, Kate; Parkhurst, Justin; Thow, Anne Marie; Walls, Helen
2018-01-01
Introduction Generating country-level political commitment will be critical to driving forward action throughout the United Nations Decade of Action on Nutrition (2016–2025). In this review of the empirical nutrition policy literature, we ask: what factors generate, sustain and constrain political commitment for nutrition, how and under what circumstances? Our aim is to inform strategic ‘commitment-building’ actions. Method We adopted a framework synthesis method and realist review protocol. An initial framework was derived from relevant theory and then populated with empirical evidence to test and modify it. Five steps were undertaken: initial theoretical framework development; search for relevant empirical literature; study selection and quality appraisal; data extraction, analysis and synthesis and framework modification. Results 75 studies were included. We identified 18 factors that drive commitment, organised into five categories: actors; institutions; political and societal contexts; knowledge, evidence and framing; and, capacities and resources. Irrespective of country-context, effective nutrition actor networks, strong leadership, civil society mobilisation, supportive political administrations, societal change and focusing events, cohesive and resonant framing, and robust data systems and available evidence were commitment drivers. Low-income and middle-income country studies also frequently reported international actors, empowered institutions, vertical coordination and capacities and resources. In upper-middle-income and high-income country studies, private sector interference frequently undermined commitment. Conclusion Political commitment is not something that simply exists or emerges accidentally; it can be created and strengthened over time through strategic action. Successfully generating commitment will likely require a core set of actions with some context-dependent adaptations. Ultimately, it will necessitate strategic actions by cohesive, resourced and strongly led nutrition actor networks that are responsive to the multifactorial, multilevel and dynamic political systems in which they operate and attempt to influence. Accelerating the formation and effectiveness of such networks over the Nutrition Decade should be a core task for all actors involved. PMID:29527338
Lorthios-Guilledroit, Agathe; Richard, Lucie; Filiatrault, Johanne
2018-06-01
Peer education is growing in popularity as a useful health promotion strategy. However, optimal conditions for implementing peer-led health promotion programs (HPPs) remain unclear. This scoping review aimed to describe factors that can influence implementation of peer-led HPPs targeting adult populations. Five databases were searched using the keywords "health promotion/prevention", "implementation", "peers", and related terms. Studies were included if they reported at least one factor associated with the implementation of community-based peer-led HPPs. Fifty-five studies were selected for the analysis. The method known as "best fit framework synthesis" was used to analyze the factors identified in the selected papers. Many factors included in existing implementation conceptual frameworks were deemed applicable to peer-led HPPs. However, other factors related to individuals, programs, and implementation context also emerged from the analysis. Based on this synthesis, an adapted theoretical framework was elaborated, grounded in a complex adaptive system perspective and specifying potential mechanisms through which factors may influence implementation of community-based peer-led HPPs. Further research is needed to test the theoretical framework against empirical data. Findings from this scoping review increase our knowledge of the optimal conditions for implementing peer-led HPPs and thereby maximizing the benefits of such programs. Copyright © 2018 Elsevier Ltd. All rights reserved.
Design and synthesis of a crystalline LiPON electrolyte
NASA Astrophysics Data System (ADS)
Holzwarth, N. A. W.; Senevirathne, Keerthi; Day, Cynthia S.; Lachgar, Abdessadek; Gross, Michael D.
2013-03-01
In the course of a computation study of the broad class of lithium phosphorus oxy-nitride materials of interest for solid electrolyte applications, Du and Holzwarth, [2] recently predicted a stable crystalline material with the stoichiometry Li2PO2N. The present paper reports the experimental preparation of the material using high temperature solid state synthesis and reports the results of experimental and calculational characterization studies. The so-named SD -Li2PO2N crystal structure has the orthorhombic space group Cmc21 with lattice constants a=9.0692(4) Å, b=5.3999(2) Å, and c=4.6856(2) Å. The structure is similar but not identical to the predicted structure, characterized by parallel arrangements of anionic phosphorus oxy-nitride chains having planar P -N -P -N backbones. Nitrogen 2p π states contribute to the strong bonding and to the chemical and thermal stablility of the material in air up to 600° C and in vacuum up to 1050° C. The measured Arrhenius activation energy for ionic conductivity is 0.6 eV which is comparable to computed vacancy migration energies in the presence of a significant population of Li+ ion vacancies. Supported by NSF grant DMR-1105485 and by a grnat from the Wake Forest University Center for Energy, Environment, and Sustainability.
Khanassov, Vladimir; Pluye, Pierre; Descoteaux, Sarah; Haggerty, Jeannie L; Russell, Grant; Gunn, Jane; Levesque, Jean-Frederic
2016-10-10
Access to community-based primary health care (hereafter, 'primary care') is a priority in many countries. Health care systems have emphasized policies that help the community 'get the right service in the right place at the right time'. However, little is known about organizational interventions in primary care that are aimed to improve access for populations in situations of vulnerability (e.g., socioeconomically disadvantaged) and how successful they are. The purpose of this scoping review was to map the existing evidence on organizational interventions that improve access to primary care services for vulnerable populations. Scoping review followed an iterative process. Eligibility criteria: organizational interventions in Organisation for Economic Cooperation and Development (OECD) countries; aiming to improve access to primary care for vulnerable populations; all study designs; published from 2000 in English or French; reporting at least one outcome (avoidable hospitalization, emergency department admission, or unmet health care needs). Main bibliographic databases (Medline, Embase, CINAHL) and team members' personal files. One researcher selected relevant abstracts and full text papers. Theory-driven synthesis: The researcher classified included studies using (i) the 'Patient Centered Access to Healthcare' conceptual framework (dimensions and outcomes of access to primary care), and (ii) the classification of interventions of the Cochrane Effective Practice and Organization of Care. Using pattern analysis, interventions were mapped in accordance with the presence/absence of 'dimension-outcome' patterns. Out of 8,694 records (title/abstract), 39 studies with varying designs were included. The analysis revealed the following pattern. Results of 10 studies on interventions classified as 'Formal integration of services' suggested that these interventions were associated with three dimensions of access (approachability, availability and affordability) and reduction of hospitalizations (four/four studies), emergency department admissions (six/six studies), and unmet healthcare needs (five/six studies). These 10 studies included seven non-randomized studies, one randomized controlled trial, one quantitative descriptive study, and one mixed methods study. Our results suggest the limited breadth of research in this area, and that it will be feasible to conduct a full systematic review of studies on the effectiveness of the formal integration of services to improve access to primary care services for vulnerable populations.
Computer simulation models of pre-diabetes populations: a systematic review protocol
Khurshid, Waqar; Pagano, Eva; Feenstra, Talitha
2017-01-01
Introduction Diabetes is a major public health problem and prediabetes (intermediate hyperglycaemia) is associated with a high risk of developing diabetes. With evidence supporting the use of preventive interventions for prediabetes populations and the discovery of novel biomarkers stratifying the risk of progression, there is a need to evaluate their cost-effectiveness across jurisdictions. In diabetes and prediabetes, it is relevant to inform cost-effectiveness analysis using decision models due to their ability to forecast long-term health outcomes and costs beyond the time frame of clinical trials. To support good implementation and reimbursement decisions of interventions in these populations, models should be clinically credible, based on best available evidence, reproducible and validated against clinical data. Our aim is to identify recent studies on computer simulation models and model-based economic evaluations of populations of individuals with prediabetes, qualify them and discuss the knowledge gaps, challenges and opportunities that need to be addressed for future evaluations. Methods and analysis A systematic review will be conducted in MEDLINE, Embase, EconLit and National Health Service Economic Evaluation Database. We will extract peer-reviewed studies published between 2000 and 2016 that describe computer simulation models of the natural history of individuals with prediabetes and/or decision models to evaluate the impact of interventions, risk stratification and/or screening on these populations. Two reviewers will independently assess each study for inclusion. Data will be extracted using a predefined pro forma developed using best practice. Study quality will be assessed using a modelling checklist. A narrative synthesis of all studies will be presented, focussing on model structure, quality of models and input data, and validation status. Ethics and dissemination This systematic review is exempt from ethics approval because the work is carried out on published documents. The findings of the review will be disseminated in a related peer-reviewed journal and presented at conferences. Reviewregistration number CRD42016047228. PMID:28982807
Identification of Host Cell Factors Associated with Astrovirus Replication in Caco-2 Cells.
Murillo, Andrea; Vera-Estrella, Rosario; Barkla, Bronwyn J; Méndez, Ernesto; Arias, Carlos F
2015-10-01
Astroviruses are small, nonenveloped viruses with a single-stranded positive-sense RNA genome causing acute gastroenteritis in children and immunocompromised patients. Since positive-sense RNA viruses have frequently been found to replicate in association with membranous structures, in this work we characterized the replication of the human astrovirus serotype 8 strain Yuc8 in Caco-2 cells, using density gradient centrifugation and free-flow zonal electrophoresis (FFZE) to fractionate cellular membranes. Structural and nonstructural viral proteins, positive- and negative-sense viral RNA, and infectious virus particles were found to be associated with a distinct population of membranes separated by FFZE. The cellular proteins associated with this membrane population in infected and mock-infected cells were identified by tandem mass spectrometry. The results indicated that membranes derived from multiple cell organelles were present in the population. Gene ontology and protein-protein interaction network analysis showed that groups of proteins with roles in fatty acid synthesis and ATP biosynthesis were highly enriched in the fractions of this population in infected cells. Based on this information, we investigated by RNA interference the role that some of the identified proteins might have in the replication cycle of the virus. Silencing of the expression of genes involved in cholesterol (DHCR7, CYP51A1) and fatty acid (FASN) synthesis, phosphatidylinositol (PI4KIIIβ) and inositol phosphate (ITPR3) metabolism, and RNA helicase activity (DDX23) significantly decreased the amounts of Yuc8 genomic and antigenomic RNA, synthesis of the structural protein VP90, and virus yield. These results strongly suggest that astrovirus RNA replication and particle assembly take place in association with modified membranes potentially derived from multiple cell organelles. Astroviruses are common etiological agents of acute gastroenteritis in children and immunocompromised patients. More recently, they have been associated with neurological diseases in mammals, including humans, and are also responsible for different pathologies in birds. In this work, we provide evidence that astrovirus RNA replication and virus assembly occur in contact with cell membranes potentially derived from multiple cell organelles and show that membrane-associated cellular proteins involved in lipid metabolism are required for efficient viral replication. Our findings provide information to enhance our knowledge of astrovirus biology and provide information that might be useful for the development of therapeutic interventions to prevent virus replication. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Identification of Host Cell Factors Associated with Astrovirus Replication in Caco-2 Cells
Murillo, Andrea; Vera-Estrella, Rosario; Barkla, Bronwyn J.; Méndez, Ernesto
2015-01-01
ABSTRACT Astroviruses are small, nonenveloped viruses with a single-stranded positive-sense RNA genome causing acute gastroenteritis in children and immunocompromised patients. Since positive-sense RNA viruses have frequently been found to replicate in association with membranous structures, in this work we characterized the replication of the human astrovirus serotype 8 strain Yuc8 in Caco-2 cells, using density gradient centrifugation and free-flow zonal electrophoresis (FFZE) to fractionate cellular membranes. Structural and nonstructural viral proteins, positive- and negative-sense viral RNA, and infectious virus particles were found to be associated with a distinct population of membranes separated by FFZE. The cellular proteins associated with this membrane population in infected and mock-infected cells were identified by tandem mass spectrometry. The results indicated that membranes derived from multiple cell organelles were present in the population. Gene ontology and protein-protein interaction network analysis showed that groups of proteins with roles in fatty acid synthesis and ATP biosynthesis were highly enriched in the fractions of this population in infected cells. Based on this information, we investigated by RNA interference the role that some of the identified proteins might have in the replication cycle of the virus. Silencing of the expression of genes involved in cholesterol (DHCR7, CYP51A1) and fatty acid (FASN) synthesis, phosphatidylinositol (PI4KIIIβ) and inositol phosphate (ITPR3) metabolism, and RNA helicase activity (DDX23) significantly decreased the amounts of Yuc8 genomic and antigenomic RNA, synthesis of the structural protein VP90, and virus yield. These results strongly suggest that astrovirus RNA replication and particle assembly take place in association with modified membranes potentially derived from multiple cell organelles. IMPORTANCE Astroviruses are common etiological agents of acute gastroenteritis in children and immunocompromised patients. More recently, they have been associated with neurological diseases in mammals, including humans, and are also responsible for different pathologies in birds. In this work, we provide evidence that astrovirus RNA replication and virus assembly occur in contact with cell membranes potentially derived from multiple cell organelles and show that membrane-associated cellular proteins involved in lipid metabolism are required for efficient viral replication. Our findings provide information to enhance our knowledge of astrovirus biology and provide information that might be useful for the development of therapeutic interventions to prevent virus replication. PMID:26246569
Gentry, Sarah; Forouhi, Nita; Notley, Caitlin
2018-03-28
Smoking prevalence remains high in some vulnerable groups, including those who misuse substances, have a mental illness, are homeless or are involved with the criminal justice system. E-cigarette use is increasing and may support smoking cessation/reduction. Systematic review of quantitative and qualitative data on the effectiveness of e-cigarettes for smoking cessation/reduction among vulnerable groups. Databases searched were MEDLINE, EMBASE, PsychINFO, CINAHL, ASSIA, ProQuest Dissertations and Theses and Open Grey. Narrative synthesis of quantitative data and thematic synthesis of qualitative data. 2628 records and 46 full texts were screened; 9 studies were identified for inclusion. Due to low quality of evidence, it is uncertain whether e-cigarettes are effective for smoking cessation in vulnerable populations. A moderate quality study suggested e-cigarettes were as effective as nicotine replacement therapy. Four studies suggested significant smoking reduction, however three were uncontrolled and had sample sizes below 30. A prospective cohort study found no differences between e-cigarette users and non-users. No significant adverse events and minimal side effects were identified. Qualitative thematic synthesis revealed barriers and facilitators associated with each component of the COM-B (capability, opportunity, motivation, behaviour) model, including practical barriers; perceptions of effectiveness for cessation/reduction; design features contributing to automatic and reflective motivation; smoking bans facilitating practical opportunity; and social connectedness increasing social opportunity. Further research is needed to identify the most appropriate device types for practicality and safety, level of support required in e-cigarette interventions, and to compare e-cigarettes with current best practice smoking cessation support among vulnerable groups. Smoking prevalence among people with mental illness, substance misuse, homelessness or criminal justice system involvement remains high. E-cigarettes could support cessation. This systematic review found limited quantitative evidence assessing effectiveness. No serious adverse events were identified. Qualitative thematic synthesis revealed barriers and facilitators mapping to each component of the COM-B (capability, opportunity, motivation, behaviour) model, including practical barriers; perceived effectiveness; design features contributing to automatic and reflective motivation; smoking bans facilitating practical opportunity; and social connectedness increasing social opportunity. Further research should consider appropriate devices for practicality and safety, concurrent support, and comparison with best practice smoking cessation support.
Vocational Support Approaches in Autism Spectrum Disorder: A Synthesis Review of the Literature
ERIC Educational Resources Information Center
Nicholas, David B.; Attridge, Mark; Zwaigenbaum, Lonnie; Clarke, Margaret
2015-01-01
This synthesis-based analysis identifies and reviews studies evaluating vocational resources for adults with autism spectrum disorder. It is based on a larger systematic review of intervention studies in autism spectrum disorder, from which a critical interpretive synthesis was conducted on studies related to vocation and autism spectrum disorder.…
Density-dependent vulnerability of forest ecosystems to drought
Bottero, Alessandra; D'Amato, Anthony W.; Palik, Brian J.; Bradford, John B.; Fraver, Shawn; Battaglia, Mike A.; Asherin, Lance A.
2017-01-01
1. Climate models predict increasing drought intensity and frequency for many regions, which may have negative consequences for tree recruitment, growth and mortality, as well as forest ecosystem services. Furthermore, practical strategies for minimizing vulnerability to drought are limited. Tree population density, a metric of tree abundance in a given area, is a primary driver of competitive intensity among trees, which influences tree growth and mortality. Manipulating tree population density may be a mechanism for moderating drought-induced stress and growth reductions, although the relationship between tree population density and tree drought vulnerability remains poorly quantified, especially across climatic gradients.2. In this study, we examined three long-term forest ecosystem experiments in two widely distributed North American pine species, ponderosa pine Pinus ponderosa (Lawson & C. Lawson) and red pine Pinus resinosa (Aiton), to better elucidate the relationship between tree population density, growth and drought. These experiments span a broad latitude and aridity range and include tree population density treatments that have been purposefully maintained for several decades. We investigated how tree population density influenced resistance (growth during drought) and resilience (growth after drought compared to pre-drought growth) of stand-level growth during and after documented drought events.3. Our results show that relative tree population density was negatively related to drought resistance and resilience, indicating that trees growing at lower densities were less vulnerable to drought. This result was apparent in all three forest ecosystems, and was consistent across species, stand age and drought intensity.4. Synthesis and applications. Our results highlighted that managing pine forest ecosystems at low tree population density represents a promising adaptive strategy for reducing the adverse impacts of drought on forest growth in coming decades. Nonetheless, the broader applicability of our findings to other types of forest ecosystems merits additional investigation.
Barriers and facilitators to recruitment of South Asians to health research: a scoping review
Frimer, Leora; Janssen, Patricia A; Lamers, Yvonne
2017-01-01
Objectives People of South Asian ethnicity are under-represented in health research studies. The objectives of this scoping review were to examine the barriers and facilitators to recruitment of South Asians to health research studies and to describe strategies for improving recruitment. Design Scoping review Methods Using the Arksey and O’Malley framework for scoping reviews, we comprehensively searched electronic databases (MEDLINE via PubMed, Cochrane Library, CINAHL and PsycINFO). Studies that identified barriers and facilitators to recruitment, or recruitment strategies for South Asian populations were included. Recruitment barriers, facilitators and strategies were grouped thematically and summarised narratively. Synthesis Of 1846 potentially relevant articles, 15 met the inclusion criteria and were included in the thematic synthesis. Multiple facilitators and barriers to enrolment of South Asians in health research studies were identified; these most commonly related to logistical challenges, language and cultural barriers, concerns about adverse consequences of participating and mistrust of research. Several actionable strategies were discussed, the most common being engagement of South Asian communities, demonstration of cultural competency, provision of incentives and benefits, language sensitivity through the use of translators and translated materials and the development of trust and personal relationships. Conclusion There is a growing awareness of the barriers and facilitators to recruitment of South Asian participants to health research studies. Knowledge of effective recruitment strategies and implementation during the grant funding stages may reduce the risk of poor recruitment and representation of South Asians. PMID:28576896
Bhui, Kamaldeep; McCabe, Rosemarie; Weich, Scott; Singh, Swaran; Johnson, Mark; Szczepura, Ala
2013-02-25
Black and Minority Ethnic (BME) groups in receipt of specialist mental health care have reported higher rates of detention under the mental health act, less use of psychological therapies, and more dissatisfaction. Although many explanations have been put forward to explain this, a failure of therapeutic communications may explain poorer satisfaction, disengagement from services and ethnic variations in access to less coercive care. Interventions that improve therapeutic communications may offer new approaches to tackle ethnic inequalities in experiences and outcomes. The THERACOM project is an HTA-funded evidence synthesis review of interventions to improve therapeutic communications between black and minority ethnic patients in contact with specialist mental health services and staff providing those services. This article sets out the protocol methods for a necessarily broad review topic, including appropriate search strategies, dilemmas for classifying different types of therapeutic communications and expectations of the types of interventions to improve them. The review methods will accommodate unexpected types of study and interventions. The findings will be reported in 2013, including a synthesis of the quantitative and grey literature. A particular methodological challenge is to identify and rate the quality of many different study types, for example, randomised controlled trials, observational quantitative studies, qualitative studies and case studies, which comprise the full range of hierarchies of evidence. We discuss the preliminary methodological challenges and some solutions. (PROSPERO registration number: CRD42011001661).
Non-Cholesterol Sterol Levels Predict Hyperglycemia and Conversion to Type 2 Diabetes in Finnish Men
Cederberg, Henna; Gylling, Helena; Miettinen, Tatu A.; Paananen, Jussi; Vangipurapu, Jagadish; Pihlajamäki, Jussi; Kuulasmaa, Teemu; Stančáková, Alena; Smith, Ulf; Kuusisto, Johanna; Laakso, Markku
2013-01-01
We investigated the levels of non-cholesterol sterols as predictors for the development of hyperglycemia (an increase in the glucose area under the curve in an oral glucose tolerance test) and incident type 2 diabetes in a 5-year follow-up study of a population-based cohort of Finnish men (METSIM Study, N = 1,050) having non-cholesterol sterols measured at baseline. Additionally we determined the association of 538,265 single nucleotide polymorphisms (SNP) with non-cholesterol sterol levels in a cross-sectional cohort of non-diabetic offspring of type 2 diabetes (the Kuopio cohort of the EUGENE2 Study, N = 273). We found that in a cross-sectional METSIM Study the levels of sterols indicating cholesterol absorption were reduced as a function of increasing fasting glucose levels, whereas the levels of sterols indicating cholesterol synthesis were increased as a function of increasing 2-hour glucose levels. A cholesterol synthesis marker desmosterol significantly predicted an increase, and two absorption markers (campesterol and avenasterol) a decrease in the risk of hyperglycemia and incident type 2 diabetes in a 5-year follow-up of the METSIM cohort, mainly attributable to insulin sensitivity. A SNP of ABCG8 was associated with fasting plasma glucose levels in a cross-sectional study but did not predict hyperglycemia or incident type 2 diabetes. In conclusion, the levels of some, but not all non-cholesterol sterols are markers of the worsening of hyperglycemia and type 2 diabetes. PMID:23840693
2013-01-01
Background Black and Minority Ethnic (BME) groups in receipt of specialist mental health care have reported higher rates of detention under the mental health act, less use of psychological therapies, and more dissatisfaction. Although many explanations have been put forward to explain this, a failure of therapeutic communications may explain poorer satisfaction, disengagement from services and ethnic variations in access to less coercive care. Interventions that improve therapeutic communications may offer new approaches to tackle ethnic inequalities in experiences and outcomes. Methods The THERACOM project is an HTA-funded evidence synthesis review of interventions to improve therapeutic communications between black and minority ethnic patients in contact with specialist mental health services and staff providing those services. This article sets out the protocol methods for a necessarily broad review topic, including appropriate search strategies, dilemmas for classifying different types of therapeutic communications and expectations of the types of interventions to improve them. The review methods will accommodate unexpected types of study and interventions. The findings will be reported in 2013, including a synthesis of the quantitative and grey literature. Discussion A particular methodological challenge is to identify and rate the quality of many different study types, for example, randomised controlled trials, observational quantitative studies, qualitative studies and case studies, which comprise the full range of hierarchies of evidence. We discuss the preliminary methodological challenges and some solutions. (PROSPERO registration number: CRD42011001661). PMID:23442299
Cho, Jai Young; Jaeger, Allison R; Sanford, Dominic E; Fields, Ryan C; Strasberg, Steven M
2015-09-01
A standard format for reporting observational surgical studies does not exist. This creates difficulties in comparing studies and in performing synthesis through systematic reviews and meta-analyses. This article proposes a method called "standard tabular reporting" and illustrates its use in a case series of bile duct reconstructions for biliary injuries occurring during cholecystectomy. A database dealing with biliary injuries was constructed in sections. Each section was designed to be turned into a table covering one element of the subject. Whenever possible, American College of Surgeons NSQIP "Classic Variables and Definitions" were used for forming sections and tables. However, most tables are original and specific to biliary injury. The database was populated from clinical records of patients who sustained a biliary injury during cholecystectomy. Tables were created dealing with the following subjects: demographics, index operation, presentation, classification of injury, preoperative risk assessment, preoperative laboratory values, operative repair technique, postoperative complications, and long-term outcomes. Between 1997 and 2013, 122 primary bile duct reconstructions were performed, with 1 mortality and 47 complications. Good long-term results were obtained in 113 (92.6%) patients. No secondary surgical reconstructions have been needed. Presentation of data in a standard format would facilitate comparison and synthesis of observational studies on the same subject. The biliary reconstructive methods used resulted in very satisfactory outcomes. Copyright © 2015 American College of Surgeons. Published by Elsevier Inc. All rights reserved.
Glucose Synthesis in a Protein-Based Artificial Photosynthesis System.
Lu, Hao; Yuan, Wenqiao; Zhou, Jack; Chong, Parkson Lee-Gau
2015-09-01
The objective of this study was to understand glucose synthesis of a protein-based artificial photosynthesis system affected by operating conditions, including the concentrations of reactants, reaction temperature, and illumination. Results from non-vesicle-based glyceraldehyde-3-phosphate (GAP) and glucose synthesis showed that the initial concentrations of ribulose-1,5-bisphosphate (RuBP) and adenosine triphosphate (ATP), lighting source, and temperature significantly affected glucose synthesis. Higher initial concentrations of RuBP and ATP significantly enhanced GAP synthesis, which was linearly correlated to glucose synthesis, confirming the proper functions of all catalyzing enzymes in the system. White fluorescent light inhibited artificial photosynthesis and reduced glucose synthesis by 79.2 % compared to in the dark. The reaction temperature of 40 °C was optimum, whereas lower or higher temperature reduced glucose synthesis. Glucose synthesis in the vesicle-based artificial photosynthesis system reconstituted with bacteriorhodopsin, F 0 F 1 ATP synthase, and polydimethylsiloxane-methyloxazoline-polydimethylsiloxane triblock copolymer was successfully demonstrated. This system efficiently utilized light-induced ATP to drive glucose synthesis, and 5.2 μg ml(-1) glucose was synthesized in 0.78-ml reaction buffer in 7 h. Light-dependent reactions were found to be the bottleneck of the studied artificial photosynthesis system.
[Chlorophyll synthesis in cotyledons after gamma ray irradiation of black pine seeds].
Bogdanović, M; Jelić, G
1992-01-01
The radiosensitivity of the greening system of Pinus nigra Arn. cotyledons has been studied in this paper. An exponential relation exists between the effect and dose for chlorophyll synthesis in the dark. Chlorophyll synthesis in the light roughly parallels that of chlorophyll synthesis in the dark. The restoration of chlorophyll was observed both in the light and in the dark. A stimulative effect of low doses of gamma radiation on chlorophyll synthesis was noticed. The radiosensitivity of chlorophyll a and chlorophyll b synthesis varied with the experimental conditions, suggesting that chlorophyll b synthesis might occur independently of chlorophyll a synthesis.
Wang, Jingyi; Mann, Farhana; Lloyd-Evans, Brynmor; Ma, Ruimin; Johnson, Sonia
2018-05-29
The adverse effects of loneliness and of poor perceived social support on physical health and mortality are established, but no systematic synthesis is available of their relationship with the outcomes of mental health problems over time. In this systematic review, we aim to examine the evidence on whether loneliness and closely related concepts predict poor outcomes among adults with mental health problems. We searched six databases and reference lists for longitudinal quantitative studies that examined the relationship between baseline measures of loneliness and poor perceived social support and outcomes at follow up. Thirty-four eligible papers were retrieved. Due to heterogeneity among included studies in clinical populations, predictor measures and outcomes, a narrative synthesis was conducted. We found substantial evidence from prospective studies that people with depression who perceive their social support as poorer have worse outcomes in terms of symptoms, recovery and social functioning. Loneliness has been investigated much less than perceived social support, but there is some evidence that greater loneliness predicts poorer depression outcome. There is also some preliminary evidence of associations between perceived social support and outcomes in schizophrenia, bipolar disorder and anxiety disorders. Loneliness and quality of social support in depression are potential targets for development and testing of interventions, while for other conditions further evidence is needed regarding relationships with outcomes.
Chronic ethanol feeding modulates the synthesis of digestive enzymes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ponnappa, B.C.; Hoek, J.B.; Rubin, E.
1987-05-01
The effects of chronic ethanol feeding on pancreatic protein synthesis were investigated. Protein synthesis was assessed by studying the rate of incorporation of /sup 3/H-leucine into TCA-precipitable proteins in isolated pancreatic acini from rats. Chronic ethanol ingestion increased the rate of pancreatic protein synthesis by 2-4 fold. The onset of the increase in protein synthesis was detectable two days after ethanol feeding, reached a maximum after 7 days and remained unchanged after 4 months on the ethanol-containing diet. The rate of synthesis of individual digestive enzymes was studied by SDS-PAGE on extracts obtained from purified zymogen granules. Ethanol feeding inducedmore » an increase in the rate of synthesis of most of the digestive enzymes; chymotrypsinogen, trypsinogen and an unidentified protein were increased to a greater extent than other digestive enzymes. By contrast, the synthesis of amylase was selectively decreased after ethanol feeding. These results suggest that chronic ethanol ingestion has specific effects on the rate of synthesis of individual digestive enzymes in the exocrine pancreas.« less
Ippolito, Danielle L; James, Wesley A; Tinnemore, Deborah; Huang, Raywin R; Dehart, Mary J; Williams, Julie; Wingerd, Mark A; Demons, Samandra T
2010-11-24
Group B Streptococcus (GBS) serotype (Ia, Ib, II-IX) correlates with pathogen virulence and clinical prognosis. Epidemiological studies of seroprevalence are an important metric for determining the proportion of serotypes in a given population. The purpose of this study was to evaluate the prevalence of individual GBS serotypes at Madigan Healthcare System (Madigan), the largest military tertiary healthcare facility in the Pacific Northwestern United States, and to compare seroprevalences with international locations. To determine serotype distribution at Madigan, we obtained GBS isolates from standard-of-care anogenital swabs from 207 women of indeterminate gravidity between ages 18-40 during a five month interval. Serotype was determined using a recently described molecular method of polymerase chain reaction by capsular polysaccharide synthesis (cps) genes associated with pathogen virulence. Serotypes Ia, III, and V were the most prevalent (28%, 27%, and 17%, respectively). A systematic review of global GBS seroprevalence, meta-analysis, and statistical comparison revealed strikingly similar serodistibution at Madigan relative to civilian-sector populations in Canada and the United States. Serotype Ia was the only serotype consistently higher in North American populations relative to other geographic regions (p < 0.005). The number of non-typeable isolates was significantly lower in the study (p < 0.005). This study establishes PCR-based serotyping as a viable strategy for GBS epidemiological surveillance. Our results suggest that GBS seroprevalence remains stable in North America over the past two decades.
2010-01-01
Background Group B Streptococcus (GBS) serotype (Ia, Ib, II-IX) correlates with pathogen virulence and clinical prognosis. Epidemiological studies of seroprevalence are an important metric for determining the proportion of serotypes in a given population. The purpose of this study was to evaluate the prevalence of individual GBS serotypes at Madigan Healthcare System (Madigan), the largest military tertiary healthcare facility in the Pacific Northwestern United States, and to compare seroprevalences with international locations. Methods To determine serotype distribution at Madigan, we obtained GBS isolates from standard-of-care anogenital swabs from 207 women of indeterminate gravidity between ages 18-40 during a five month interval. Serotype was determined using a recently described molecular method of polymerase chain reaction by capsular polysaccharide synthesis (cps) genes associated with pathogen virulence. Results Serotypes Ia, III, and V were the most prevalent (28%, 27%, and 17%, respectively). A systematic review of global GBS seroprevalence, meta-analysis, and statistical comparison revealed strikingly similar serodistibution at Madigan relative to civilian-sector populations in Canada and the United States. Serotype Ia was the only serotype consistently higher in North American populations relative to other geographic regions (p < 0.005). The number of non-typeable isolates was significantly lower in the study (p < 0.005). Conclusion This study establishes PCR-based serotyping as a viable strategy for GBS epidemiological surveillance. Our results suggest that GBS seroprevalence remains stable in North America over the past two decades. PMID:21106080
Banerjee, A; Udin, S; Krishna, A
2011-02-01
Factors regulating leptin synthesis during adipogenesis in wild species are not well known. Studies in the female Cynopterus sphinx bat have shown that it undergoes seasonal changes in its fat deposition and serum leptin and melatonin levels. The aim of the present study was to investigate the hormonal regulation of leptin synthesis by the white adipose tissue during the period of fat deposition in female C. sphinx. This study showed a significant correlation between the seasonal changes in serum melatonin level with the circulating leptin level (r = 0.78; P < 0.05) and with the changes in body fat mass (r = 0.88; P < 0.05) in C. sphinx. A significant correlation between circulating insulin and leptin levels (r = 0.65; P < 0.05) was also found in this species. This in vivo finding suggests that melatonin together with insulin may enhance leptin synthesis by increasing adipose tissue accumulation. The in vitro study showed that melatonin interacts synergistically with insulin in stimulating leptin synthesis by adipose tissue in C. sphinx. The study showed MT(2) receptors in adipose tissue and a stimulatory effect of melatonin on leptin synthesis, which was blocked by treatment with an MT(2) receptor antagonist, suggesting that the effect of melatonin on leptin synthesis by adipose tissue is mediated through the MT(2) receptor in C. sphinx. The in vitro study showed that the synthesis of leptin is directly proportional to the amount of glucose uptake by the adipose tissue. It further showed that melatonin together with insulin synergistically enhanced the leptin synthesis by adipose tissue through phosphorylation of mitogen-activated protein kinase in C. sphinx.
Invoking adaptation to decipher the genetic legacy of past climate change.
de Lafontaine, Guillaume; Napier, Joseph D; Petit, Rémy J; Hu, Feng Sheng
2018-05-05
Persistence of natural populations during periods of climate change is likely to depend on migration (range shifts) or adaptation. These responses were traditionally considered discrete processes and conceptually divided into the realms of ecology and evolution. In a milestone paper, Davis and Shaw (2001) argued that the interplay of adaptation and migration was central to biotic responses to Quaternary climate, but since then there has been no synthesis of efforts made to set up this research program. Here we review some of the salient findings from molecular genetic studies assessing ecological and evolutionary responses to Quaternary climate change. These studies have revolutionized our understanding of population processes associated with past species migration. However, knowledge remains limited about the role of natural selection for local adaptation of populations to Quaternary environmental fluctuations and associated range shifts, and for the footprints this might have left on extant populations. Next-generation sequencing technologies, high-resolution paleoclimate analyses, and advances in population genetic theory offer an unprecedented opportunity to test hypotheses about adaptation through time. Recent population genomics studies have greatly improved our understanding of the role of contemporary adaptation to local environments in shaping spatial patterns of genetic diversity across modern-day landscapes. Advances in this burgeoning field provide important conceptual and methodological bases to decipher the historical role of natural selection and assess adaptation to past environmental variation. We suggest that a process called "temporal conditional neutrality" has taken place: some alleles favored in glacial environments become selectively neutral in modern-day conditions, whereas some alleles that had been neutral during glacial periods become under selection in modern environments. Building on this view, we present a new integrative framework for addressing the interplay of demographic and adaptive evolutionary responses to Quaternary climate dynamics, the research agenda initially envisioned by Davis and Shaw (2001). This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
What can we learn from resource pulses?
Yang, Louie H; Bastow, Justin L; Spence, Kenneth O; Wright, Amber N
2008-03-01
An increasing number of studies in a wide range of natural systems have investigated how pulses of resource availability influence ecological processes at individual, population, and community levels. Taken together, these studies suggest that some common processes may underlie pulsed resource dynamics in a wide diversity of systems. Developing a common framework of terms and concepts for the study of resource pulses may facilitate greater synthesis among these apparently disparate systems. Here, we propose a general definition of the resource pulse concept, outline some common patterns in the causes and consequences of resource pulses, and suggest a few key questions for future investigations. We define resource pulses as episodes of increased resource availability in space and time that combine low frequency (rarity), large magnitude (intensity), and short duration (brevity), and emphasize the importance of considering resource pulses at spatial and temporal scales relevant to specific resource-onsumer interactions. Although resource pulses are uncommon events for consumers in specific systems, our review of the existing literature suggests that pulsed resource dynamics are actually widespread phenomena in nature. Resource pulses often result from climatic and environmental factors, processes of spatiotemporal accumulation and release, outbreak population dynamics, or a combination of these factors. These events can affect life history traits and behavior at the level of individual consumers, numerical responses at the population level, and indirect effects at the community level. Consumers show strategies for utilizing ephemeral resources opportunistically, reducing resource variability by averaging over larger spatial scales, and tolerating extended interpulse periods of reduced resource availability. Resource pulses can also create persistent effects in communities through several mechanisms. We suggest that the study of resource pulses provides opportunities to understand the dynamics of many specific systems, and may also contribute to broader ecological questions at individual, population, and community levels.
The co-occurrence of aggression and self-harm: systematic literature review.
O'Donnell, Orla; House, Allan; Waterman, Mitch
2015-04-01
Epidemiological research supports an association between aggression and self-harm through data on the frequency with which individuals exhibit both behaviours. Unbiased evidence, however, is needed to draw conclusions about the nature and extent of co-occurrence. Systematic review of published studies was undertaken to evaluate whether or not the frequency with which aggression and self-harm co-occur is beyond that which would be expected by chance. Outcome measures included: (a) between-group differences on a standardised aggression/self-harm measure - the groups defined by scores on a measure of the other behaviour; (b) correlations between the two behaviours; (c) co-occurrence rates in populations defined by the presence of either behaviour; (d) co-occurrence rates in populations not defined by either behaviour. Odds ratios were calculated for studies presenting complete frequency data. 123 studies, some yielding more than one type of result, met the inclusion criteria. Most case-control studies found elevated levels of aggression in self-harming populations (or self-harm in aggressive populations) compared to controls. The majority of correlational, co-occurrence rate, and odds ratio data found aggression and self-harm to be associated. Results were subject to descriptive synthesis only and thus, unable to report an overall effect size. Evidence suggests that aggression and self-harm frequently co-occur. Such evidence necessitates more theoretical discussion and associated research on the source and nature of co-occurrence. Nonetheless, individuals who present with one behaviour may be considered an 'at-risk' group in terms of exhibiting the other. Such evidence holds implications for practice (e.g. risk assessment). Copyright © 2015. Published by Elsevier B.V.
Chen, Zhuo; Tao, Sha; Gao, Yong; Zhang, Ju; Hu, Yanling; Mo, Linjian; Kim, Seong-Tae; Yang, Xiaobo; Tan, Aihua; Zhang, Haiying; Qin, Xue; Li, Li; Wu, Yongming; Zhang, Shijun; Zheng, S Lilly; Xu, Jianfeng; Mo, Zengnan; Sun, Jielin
2013-12-01
Sex hormones and gonadotropins exert a wide variety of effects in physiological and pathological processes. Accumulated evidence shows a strong heritable component of circulating concentrations of these hormones. Recently, several genome-wide association studies (GWASs) conducted in Caucasians have identified multiple loci that influence serum levels of sex hormones. However, the genetic determinants remain unknown in Chinese populations. In this study, we aimed to identify genetic variants associated with major sex hormones, gonadotropins, including testosterone, oestradiol, follicle-stimulating hormone (FSH), luteinising hormone (LH) and sex hormone binding globulin (SHBG) in a Chinese population. A two-stage GWAS was conducted in a total of 3495 healthy Chinese men (1999 subjects in the GWAS discovery stage and 1496 in the confirmation stage). We identified a novel genetic region at 15q21.2 (rs2414095 in CYP19A1), which was significantly associated with oestradiol and FSH in the Chinese population at a genome-wide significant level (p=6.54×10(-31) and 1.59×10(-16), respectively). Another single nucleotide polymorphism in CYP19A1 gene was significantly associated with oestradiol level (rs2445762, p=7.75×10(-28)). In addition, we confirmed the previous GWAS-identified locus at 17p13.1 for testosterone (rs2075230, p=1.13×10(-8)) and SHBG level (rs2075230, p=4.75×10(-19)) in the Chinese population. This study is the first GWAS investigation of genetic determinants of FSH and LH. The identification of novel susceptibility loci may provide more biological implications for the synthesis and metabolism of these hormones. More importantly, the confirmation of the genetic loci for testosterone and SHBG suggests common genetic components shared among different ethnicities.
Porter, Judi; Nguo, Kay; Gibson, Simone; Huggins, Catherine E; Collins, Jorja; Kellow, Nicole J; Truby, Helen
2018-03-26
Increasing population lifespan necessitates a greater understanding of nutritional needs in older adults (65 year and over). A synthesis of total energy expenditure in the older population has not been undertaken and is needed to inform nutritional requirements. We aimed to establish the extent of the international evidence for total energy expenditure (TEE) using doubly-labelled water (DLW) in older adults (65 years and over), report challenges in obtaining primary data, and make recommendations for future data sharing. Four databases were searched to identify eligible studies; original research of any study design where participant level TEE was measured using DLW in participants aged ≥65 years. Once studies were identified for inclusion, authors were contacted where data were not publicly available. Screening was undertaken of 1223 records; the review of 317 full text papers excluded 170 records. Corresponding or first authors of 147 eligible studies were contacted electronically. Participant level data were publicly available or provided by authors for 45 publications (890 participants aged ≥65 years, with 248 aged ≥80 years). Sixty-seven percent of the DLW data in this population were unavailable due to authors unable to be contacted or declining to participate, or data being irretrievable. The lack of data access limits the value of the original research and its contribution to nutrition science. Openly accessible DLW data available through publications or a new international data repository would facilitate greater integration of current research with previous findings and ensure evidence is available to support the needs of the ageing population. The protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO), registration number CRD42016047549 .
NASA Astrophysics Data System (ADS)
Volonteri, Marta; Reines, Amy E.; Atek, Hakim; Stark, Daniel P.; Trebitsch, Maxime
2017-11-01
The first billion years of the Universe has been a pivotal time: stars, black holes (BHs), and galaxies formed and assembled, sowing the seeds of galaxies as we know them today. Detecting, identifying, and understanding the first galaxies and BHs is one of the current observational and theoretical challenges in galaxy formation. In this paper we present a population synthesis model aimed at galaxies, BHs, and active galactic nuclei (AGNs) at high redshift. The model builds a population based on empirical relations. The spectral energy distribution of galaxies is determined by age and metallicity, and that of AGNs by BH mass and accretion rate. We validate the model against observations, and predict properties of galaxies and AGN in other wavelength and/or luminosity ranges, estimating the contamination of stellar populations (normal stars and high-mass X-ray binaries) for AGN searches from the infrared to X-rays, and vice versa for galaxy searches. For high-redshift galaxies with stellar ages < 1 {Gyr}, we find that disentangling stellar and AGN emission is challenging at restframe UV/optical wavelengths, while high-mass X-ray binaries become more important sources of confusion in X-rays. We propose a color-color selection in the James Webb Space Telescope bands to separate AGN versus star-dominated galaxies in photometric observations. We also estimate the AGN contribution, with respect to massive, hot, and metal-poor stars, at driving high-ionization lines, such as C IV and He II. Finally, we test the influence of the minimum BH mass and occupation fraction of BHs in low-mass galaxies on the restframe UV/near-IR and X-ray AGN luminosity function.
Walker, Kate; Seaman, Shaun R; De Angelis, Daniela; Presanis, Anne M; Dodds, Julie P; Johnson, Anne M; Mercey, Danielle; Gill, O Noel; Copas, Andrew J
2011-10-01
Hard-to-reach population subgroups are typically investigated using convenience sampling, which may give biased estimates. Combining information from such surveys, a probability survey and clinic surveillance, can potentially minimize the bias. We developed a methodology to estimate the prevalence of undiagnosed HIV infection among men who have sex with men (MSM) in England and Wales aged 16-44 years in 2003, making fuller use of the available data than earlier work. We performed a synthesis of three data sources: genitourinary medicine clinic surveillance (11 380 tests), a venue-based convenience survey including anonymous HIV testing (3702 MSM) and a general population sexual behaviour survey (134 MSM). A logistic regression model to predict undiagnosed infection was fitted to the convenience survey data and then applied to the MSMs in the population survey to estimate the prevalence of undiagnosed infection in the general MSM population. This estimate was corrected for selection biases in the convenience survey using clinic surveillance data. A sensitivity analysis addressed uncertainty in our assumptions. The estimated prevalence of undiagnosed HIV in MSM was 2.4% [95% confidence interval (95% CI 1.7-3.0%)], and between 1.6% (95% CI 1.1-2.0%) and 3.3% (95% CI 2.4-4.1%) depending on assumptions; corresponding to 5500 (3390-7180), 3610 (2180-4740) and 7570 (4790-9840) men, and undiagnosed fractions of 33, 24 and 40%, respectively. Our estimates are consistent with earlier work that did not make full use of data sources. Reconciling data from multiple sources, including probability-, clinic- and venue-based convenience samples can reduce bias in estimates. This methodology could be applied in other settings to take full advantage of multiple imperfect data sources.
Ages of Massive Galaxies at 0.5 > z > 2.0 from 3D-HST Rest-frame Optical Spectroscopy
NASA Astrophysics Data System (ADS)
Fumagalli, Mattia; Franx, Marijn; van Dokkum, Pieter; Whitaker, Katherine E.; Skelton, Rosalind E.; Brammer, Gabriel; Nelson, Erica; Maseda, Michael; Momcheva, Ivelina; Kriek, Mariska; Labbé, Ivo; Lundgren, Britt; Rix, Hans-Walter
2016-05-01
We present low-resolution near-infrared stacked spectra from the 3D-HST survey up to z = 2.0 and fit them with commonly used stellar population synthesis models: BC03, FSPS10 (Flexible Stellar Population Synthesis), and FSPS-C3K. The accuracy of the grism redshifts allows the unambiguous detection of many emission and absorption features and thus a first systematic exploration of the rest-frame optical spectra of galaxies up to z = 2. We select massive galaxies ({log}({M}*/{M}⊙ )\\gt 10.8), we divide them into quiescent and star-forming via a rest-frame color-color technique, and we median-stack the samples in three redshift bins between z = 0.5 and z = 2.0. We find that stellar population models fit the observations well at wavelengths below the 6500 Å rest frame, but show systematic residuals at redder wavelengths. The FSPS-C3K model generally provides the best fits (evaluated with χ 2 red statistics) for quiescent galaxies, while BC03 performs the best for star-forming galaxies. The stellar ages of quiescent galaxies implied by the models, assuming solar metallicity, vary from 4 Gyr at z ˜ 0.75 to 1.5 Gyr at z ˜ 1.75, with an uncertainty of a factor of two caused by the unknown metallicity. On average, the stellar ages are half the age of the universe at these redshifts. We show that the inferred evolution of ages of quiescent galaxies is in agreement with fundamental plane measurements, assuming an 8 Gyr age for local galaxies. For star-forming galaxies, the inferred ages depend strongly on the stellar population model and the shape of the assumed star-formation history.
NASA Astrophysics Data System (ADS)
Cheng, Liantao; Zhang, Fenghui; Kang, Xiaoyu; Wang, Lang
2018-05-01
In evolutionary population synthesis (EPS) models, we need to convert stellar evolutionary parameters into spectra via interpolation in a stellar spectral library. For theoretical stellar spectral libraries, the spectrum grid is homogeneous on the effective-temperature and gravity plane for a given metallicity. It is relatively easy to derive stellar spectra. For empirical stellar spectral libraries, stellar parameters are irregularly distributed and the interpolation algorithm is relatively complicated. In those EPS models that use empirical stellar spectral libraries, different algorithms are used and the codes are often not released. Moreover, these algorithms are often complicated. In this work, based on a radial basis function (RBF) network, we present a new spectrum interpolation algorithm and its code. Compared with the other interpolation algorithms that are used in EPS models, it can be easily understood and is highly efficient in terms of computation. The code is written in MATLAB scripts and can be used on any computer system. Using it, we can obtain the interpolated spectra from a library or a combination of libraries. We apply this algorithm to several stellar spectral libraries (such as MILES, ELODIE-3.1 and STELIB-3.2) and give the integrated spectral energy distributions (ISEDs) of stellar populations (with ages from 1 Myr to 14 Gyr) by combining them with Yunnan-III isochrones. Our results show that the differences caused by the adoption of different EPS model components are less than 0.2 dex. All data about the stellar population ISEDs in this work and the RBF spectrum interpolation code can be obtained by request from the first author or downloaded from http://www1.ynao.ac.cn/˜zhangfh.
Sibley, Kathryn M.; Howe, Tracey; Lamb, Sarah E.; Lord, Stephen R.; Maki, Brian E.; Rose, Debra J.; Scott, Vicky; Stathokostas, Liza; Straus, Sharon E.; Jaglal, Susan B.
2015-01-01
Background Standing balance is imperative for mobility and avoiding falls. Use of an excessive number of standing balance measures has limited the synthesis of balance intervention data and hampered consistent clinical practice. Objective To develop recommendations for a core outcome set (COS) of standing balance measures for research and practice among adults. Methodology A combination of scoping reviews, literature appraisal, anonymous voting and face-to-face meetings with fourteen invited experts from a range of disciplines with international recognition in balance measurement and falls prevention. Consensus was sought over three rounds using pre-established criteria. Data sources The scoping review identified 56 existing standing balance measures validated in adult populations with evidence of use in the past five years, and these were considered for inclusion in the COS. Results Fifteen measures were excluded after the first round of scoring and a further 36 after round two. Five measures were considered in round three. Two measures reached consensus for recommendation, and the expert panel recommended that at a minimum, either the Berg Balance Scale or Mini Balance Evaluation Systems Test be used when measuring standing balance in adult populations. Limitations Inclusion of two measures in the COS may increase the feasibility of potential uptake, but poses challenges for data synthesis. Adoption of the standing balance COS does not constitute a comprehensive balance assessment for any population, and users should include additional validated measures as appropriate. Conclusions The absence of a gold standard for measuring standing balance has contributed to the proliferation of outcome measures. These recommendations represent an important first step towards greater standardization in the assessment and measurement of this critical skill and will inform clinical research and practice internationally. PMID:25768435
ERIC Educational Resources Information Center
Gyarmathy, Éva; Senior, John
2018-01-01
Models of giftedness in the 21st century tend to describe talent as a social construct. Research now indicates that certain talented populations that are composed of multiple exceptional individuals are excluded from talent development programmes. Recognizing how well the environment best fits individual needs at particular key developmental…
Come Out, Come Out, Wherever You Are: A Synthesis of Queer Research in Education.
ERIC Educational Resources Information Center
Jackson, Janna
This paper examines the research in the area of teachers' attitudes, practices, and beliefs about gay and lesbian issues in education, focusing on homosexuality because although there is some overlap in regards to both the population and the issues, the differences between gay and transgendered issues add another layer of complexity to an already…
A soil burn severity index for understanding soil-fire relations in tropical forests
Theresa B. Jain; William A. Gould; Russell T. Graham; David S. Pilliod; Leigh B. Lentile; Grizelle Gonzalez
2008-01-01
Methods for evaluating the impact of fires within tropical forests are needed as fires become more frequent and human populations and demands on forests increase. Short- and long-term fire effects on soils are determined by the prefire, fire, and postfire environments. We placed these components within a fire-disturbance continuum to guide our literature synthesis and...
An overview of the Southern Nevada Agency Partnership Science and Research Synthesis [Chapter 1
Jeanne C. Chambers; Matthew L. Brooks; Kent Turner; Carol B. Raish; Steven M. Ostoja
2013-01-01
Southern Nevada is characterized by an arid to semi-arid environment with numerous cultural resources and a high level of biological diversity. Since 1980, the human population of the region has increased at unprecedented rates largely due to the expansion of suburban areas (Hughson 2009). The various human activities associated with this growth and the interactions of...
d/Deaf and Hard of Hearing Multilingual Learners: The Development of Communication and Language
ERIC Educational Resources Information Center
Pizzo, Lianna
2016-01-01
The author examines the theory and research relevant to educating d/Deaf and Hard of Hearing Multilingual Learners (DMLs). There is minimal research on this population, yet a synthesis of related theory, research, and practice on spoken-language bilinguals can be used to add to the body of knowledge on these learners. Specifically, the author…
Population Synthesis of Radio and Y-ray Millisecond Pulsars Using Markov Chain Monte Carlo
NASA Astrophysics Data System (ADS)
Gonthier, Peter L.; Billman, C.; Harding, A. K.
2013-04-01
We present preliminary results of a new population synthesis of millisecond pulsars (MSP) from the Galactic disk using Markov Chain Monte Carlo techniques to better understand the model parameter space. We include empirical radio and γ-ray luminosity models that are dependent on the pulsar period and period derivative with freely varying exponents. The magnitudes of the model luminosities are adjusted to reproduce the number of MSPs detected by a group of ten radio surveys and by Fermi, predicting the MSP birth rate in the Galaxy. We follow a similar set of assumptions that we have used in previous, more constrained Monte Carlo simulations. The parameters associated with the birth distributions such as those for the accretion rate, magnetic field and period distributions are also free to vary. With the large set of free parameters, we employ Markov Chain Monte Carlo simulations to explore the large and small worlds of the parameter space. We present preliminary comparisons of the simulated and detected distributions of radio and γ-ray pulsar characteristics. We express our gratitude for the generous support of the National Science Foundation (REU and RUI), Fermi Guest Investigator Program and the NASA Astrophysics Theory and Fundamental Program.
NASA Astrophysics Data System (ADS)
Sankarasubramanian, A.; Sabo, J. L.; Larson, K. L.; Seo, S. B.; Sinha, T.; Bhowmik, R.; Vidal, A. Ruhi; Kunkel, K.; Mahinthakumar, G.; Berglund, E. Z.; Kominoski, J.
2017-07-01
Recent U.S. Geological Survey water-use report suggests that increasing water-use efficiency could mitigate the supply-and-demand imbalance arising from changing climate and growing population. However, this rich data have neither analyzed to understand the underlying patterns, nor have been investigated to identify the factors contributing to this increased efficiency. A national-scale synthesis of public supply withdrawals ("withdrawals") reveals a strong North-south gradient in public supply water use with the increasing population in the South contributing to increased withdrawal. Contrastingly, a reverse South-north gradient exists in per capita withdrawals ("efficiency"), with northern states consistently improving the efficiency, while the southern states' efficiency declined. Our analyses of spatial patterns of per capita withdrawals further demonstrate that urban counties exhibit improved efficiency over rural counties. Improved efficiency is also demonstrated over high-income and well-educated counties. Given the potential implications of the findings in developing long-term water conservation measures (i.e., increasing block rates), we argue the need for frequent updates, perhaps monthly to annual, of water-use data for identifying effective strategies that control the water-use efficiency in various geographic settings under a changing climate.
Bussy, Ugo; Chung-Davidson, Yu-Wen; Buchinger, Tyler; Li, Ke; Smith, Scott A; Jones, A Daniel; Li, Weiming
2018-02-01
The sea lamprey (Petromyzon marinus) is a destructive invasive species in the Great Lakes that contributed to the collapse of native fish populations in the mid-1900s. 3-Trifluoromethyl-4-nitrophenol (TFM) is a selective pesticide that has been applied to sea lamprey infested tributaries of the Great Lakes to kill larvae since the 1960s and has reduced the populations by as much as 90%. However, the metabolism of TFM by sea lamprey and non-target species is not fully illuminated. Elucidation of TFM metabolism is critical for understanding its mode of action and possible environmental impact. Here, we describe the screening, identification, synthesis and structural characterization of TFM metabolites in livers from sea lamprey and three non-target species that differ in their ability to survive TFM exposure. We identified glucuronidation, sulfation, N-acetylation, glutathione conjugation, and aromatic nitro group reduction as potential detoxification mechanisms. Seven metabolites were synthesized for use as markers of TFM metabolism in fish. Quantitative 1 H NMR was used to assay synthesized metabolite stock solutions that were then used as standard material to develop a quantitative LC-MS/MS method for TFM metabolites.
Prevalence of tinnitus and hyperacusis in children and adolescents: a systematic review.
Rosing, Susanne Nemholt; Schmidt, Jesper Hvass; Wedderkopp, Niels; Baguley, David M
2016-06-03
To systematically review studies of the epidemiology of tinnitus and hyperacusis in children and young people, in order to determine the methodological differences implicated in the variability of prevalence estimates and the influence of population characteristics on childhood tinnitus and hyperacusis. Articles were retrieved from PubMed, EMBASE and Scopus databases and from the relevant reference lists using the methods described in the study protocol, which has previously been published. Reporting Items for Systematic Review (PRISMA) guidelines were followed. Studies addressing childhood prevalence, for example, children and young people aged 5-19 years. 2 reviewers independently assessed the studies for eligibility, extracted data and assessed study consistency. Owing to the heterogeneity in the methodologies among the reported studies, only narrative synthesis of the results was carried out. Having identified 1032 publications, 131 articles were selected and 25 articles met the inclusion criteria and had sufficient methodological consistency to be included. Prevalence estimates of tinnitus range from 4.7% to 46% in the general paediatric population and among children with normal hearing, and from 23.5% to 62.2% of population of children with hearing loss. Reported prevalence ranged from 6% to 41.9% when children with hearing loss and normal hearing were both included. The prevalence of hyperacusis varied from 3.2% to 17.1%. Data on prevalence vary considerably according to the study design, study population and the research question posed. The age range of children studied was varied and a marked degree of variation between definitions (tinnitus, hyperacusis) and measures (severity, perception, annoyance) was observed. The lack of consistency among studies indicates the necessity of examining the epidemiology of tinnitus and hyperacusis in children and adolescents with a set of standardised criteria. CRD42014013456. 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/
Prevalence of tinnitus and hyperacusis in children and adolescents: a systematic review
Rosing, Susanne Nemholt; Schmidt, Jesper Hvass; Wedderkopp, Niels; Baguley, David M
2016-01-01
Objectives To systematically review studies of the epidemiology of tinnitus and hyperacusis in children and young people, in order to determine the methodological differences implicated in the variability of prevalence estimates and the influence of population characteristics on childhood tinnitus and hyperacusis. Data sources Articles were retrieved from PubMed, EMBASE and Scopus databases and from the relevant reference lists using the methods described in the study protocol, which has previously been published. Reporting Items for Systematic Review (PRISMA) guidelines were followed. Eligibility criteria Studies addressing childhood prevalence, for example, children and young people aged 5–19 years. Data selection 2 reviewers independently assessed the studies for eligibility, extracted data and assessed study consistency. Owing to the heterogeneity in the methodologies among the reported studies, only narrative synthesis of the results was carried out. Results Having identified 1032 publications, 131 articles were selected and 25 articles met the inclusion criteria and had sufficient methodological consistency to be included. Prevalence estimates of tinnitus range from 4.7% to 46% in the general paediatric population and among children with normal hearing, and from 23.5% to 62.2% of population of children with hearing loss. Reported prevalence ranged from 6% to 41.9% when children with hearing loss and normal hearing were both included. The prevalence of hyperacusis varied from 3.2% to 17.1%. Conclusions Data on prevalence vary considerably according to the study design, study population and the research question posed. The age range of children studied was varied and a marked degree of variation between definitions (tinnitus, hyperacusis) and measures (severity, perception, annoyance) was observed. The lack of consistency among studies indicates the necessity of examining the epidemiology of tinnitus and hyperacusis in children and adolescents with a set of standardised criteria. Trial registration number CRD42014013456. PMID:27259524
Impact of an AGN featureless continuum on estimation of stellar population properties
NASA Astrophysics Data System (ADS)
Cardoso, Leandro S. M.; Gomes, Jean Michel; Papaderos, Polychronis
2017-08-01
The effect of the featureless power-law (PL) continuum of an active galactic nucleus (AGN) on the estimation of physical properties of galaxies with optical population spectral synthesis (PSS) remains largely unknown. With the goal of a quantitative examination of this issue, we fit synthetic galaxy spectra representing a wide range of galaxy star formation histories (SFHs) and including distinct PL contributions of the form Fν ∝ ν- α with the PSS code Starlight to study to which extent various inferred quantities (e.g. stellar mass, mean age, and mean metallicity) match the input. The synthetic spectral energy distributions (SEDs) computed with our evolutionary spectral synthesis code include an AGN PL component with 0.5 ≤ α ≤ 2 and a fractional contribution 0.2 ≤ xAGN ≤ 0.8 to the monochromatic flux at 4020 Å. At the empirical AGN detection threshold xAGN ≃ 0.26 that we previously inferred in a pilot study on this subject, our results show that the neglect of a PL component in spectral fitting can lead to an overestimation by 2 dex in stellar mass and by up to 1 and 4 dex in the light- and mass-weighted mean stellar age, respectively, whereas the light- and mass-weighted mean stellar metallicity are underestimated by up to 0.3 and 0.6 dex, respectively. These biases, which become more severe with increasing xAGN, are essentially independent of the adopted SFH and show a complex behaviour with evolutionary time and α. Other fitting set-ups including either a single PL or multiple PLs in the base reveal, on average, much lower unsystematic uncertainties of the order of those typically found when fitting purely stellar SEDs with stellar templates, however, reaching locally up to 1, 3 and 0.4 dex in mass, age and metallicity, respectively. Our results underscore the importance of an accurate modelling of the AGN spectral contribution in PSS fits as a minimum requirement for the recovery of the physical and evolutionary properties of stellar populations in active galaxies. In particular, this study draws attention to the fact that the neglect of a PL in spectral modelling of these systems may lead to substantial overestimates in stellar mass and age, thereby leading to potentially significant biases in our understanding of the co-evolution of AGN with their galaxy hosts.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moorhouse, Saul J.; Wu, Yue; O’Hare, Dermot, E-mail: dermot.ohare@chem.ox.ac.uk
A newly developed in situ monochromatic high-energy X-ray diffraction setup was used to investigate the synthesis of MOFs using cation-impregnated polymer resin beads as a ion source. The Co–NDC–DMF (NDC=2,6-naphthalenedicarboxylate; DMF=dimethylformamide) system was investigated, a system which is known to produce at least three distinct frameworks. It was found that the resin-assisted synthesis results in the preferential formation of a topology previously impossible to synthesise in bulk, while the comparable nitrate-salt synthesis appeared to form an alternative phases. It was also found that the resin-assisted synthesis is highly diffusion-controlled. - Graphical abstract: In situ monochromatic high-energy X-ray diffraction study ofmore » a MOF synthesis. - Highlights: • Resin-assisted solvothermal MOF synthesis was studied using in situ diffraction. • Full kinetics of reaction can be obtained from in situ data. • Kinetics show that this resin-assisted synthesis is diffusion controlled. • Resin-assisted synthesis enables the production of an alternative bulk phase.« less
Tong, Na; Sheng, Xiaojing; Wang, Meilin; Fang, Yongjun; Shi, Danni; Zhang, Zhizhong; Zhang, Zhengdong
2011-10-01
Methylenetetrahydrofolate reductase (MTHFR) is involved in DNA methylation and nucleotide synthesis. Accumulated evidence has demonstrated that C677T and A1298C polymorphisms of the MTHFR gene are associated with acute lymphoblastic leukemia (ALL) risk, but the results have been inconclusive. To determine a more precise estimation, we performed a meta-analysis of 28 studies with 4240 cases and 9289 controls. We found that the 677TT genotype showed a reduced risk of ALL compared with the 677CC genotype in the overall population (odds ratio [OR] 0.76, 95% confidence interval [CI] 0.61-0.92). The reduced risk was pronounced only among the Caucasian population (OR 0.68, 95% CI 0.51-0.90), not the Asian (OR 0.89, 95% CI 0.75-1.05). For the MTHFR A1298C polymorphism, no significant association with ALL susceptibility was observed in the pooled analyses. However, significantly increased ALL risk was found in childhood in the comparison of 1298CA versus AA genotype. This study provides evidence that MTHFR polymorphisms may play an important role in the development of ALL.
Lim, Jong-Min; Bertrand, Nicolas; Valencia, Pedro M.; Rhee, Minsoung; Langer, Robert; Jon, Sangyong; Farokhzad, Omid C.; Karnik, Rohit
2014-01-01
Microfluidic synthesis of nanoparticles (NPs) can enhance the controllability and reproducibility in physicochemical properties of NPs compared to bulk synthesis methods. However, applications of microfluidic synthesis are typically limited to in vitro studies due to low production rates. Herein, we report the parallelization of NP synthesis by 3D hydrodynamic flow focusing (HFF) using a multilayer microfluidic system to enhance the production rate without losing the advantages of reproducibility, controllability, and robustness. Using parallel 3D HFF, polymeric poly(lactide-co-glycolide)-b-polyethyleneglycol (PLGA-PEG) NPs with sizes tunable in the range of 13–150 nm could be synthesized reproducibly with high production rate. As a proof of concept, we used this system to perform in vivo pharmacokinetic and biodistribution study of small (20 nm diameter) PLGA-PEG NPs that are otherwise difficult to synthesize. Microfluidic parallelization thus enables synthesis of NPs with tunable properties with production rates suitable for both in vitro and in vivo studies. PMID:23969105
Jones, P H; Shakdher, S; Singh, P
2017-04-01
Salient findings and interpretations from the canimpact clinical cancer research study are visually represented in two synthesis maps for the purpose of communicating an integrated presentation of the study to clinical cancer researchers and policymakers. Synthesis maps integrate evidence and expertise into a visual narrative for knowledge translation and communication. A clinical system synthesis map represents the current Canadian primary care and cancer practice systems, proposed as a visual knowledge translation from the mixed-methods canimpact study to inform Canadian clinical research, policy, and practice discourses. Two synthesis maps, drawn together from multiple canimpact investigations and sources, were required to articulate critical differences between the clinical system and patient perspectives. The synthesis map of Canada-wide clinical cancer systems illustrates the relationships between primary care and the full cancer continuum. A patient-centred map was developed to represent the cancer (and primary care) journeys as experienced by breast and colorectal cancer patients.
Heinmets, F; Leary, R H
1991-06-01
A model system (1) was established to analyze purine and pyrimidine metabolism. This system has been expanded to include macrosimulation of DNA synthesis and the study of its regulation by terminal deoxynucleoside triphosphates (dNTPs) via a complex set of interactions. Computer experiments reveal that our model exhibits adequate and reasonable sensitivity in terms of dNTP pool levels and rates of DNA synthesis when inputs to the system are varied. These simulation experiments reveal that in order to achieve maximum DNA synthesis (in terms of purine metabolism), a proper balance is required in guanine and adenine input into this metabolic system. Excessive inputs will become inhibitory to DNA synthesis. In addition, studies are carried out on rates of DNA synthesis when various parameters are changed quantitatively. The current system is formulated by 110 differential equations.
Prostate-Specific Antigen (PSA)–Based Population Screening for Prostate Cancer: An Economic Analysis
Tawfik, A
2015-01-01
Background The prostate-specific antigen (PSA) blood test has become widely used in Canada to test for prostate cancer (PC), the most common cancer among Canadian men. Data suggest that population-based PSA screening may not improve overall survival. Objectives This analysis aimed to review existing economic evaluations of population-based PSA screening, determine current spending on opportunistic PSA screening in Ontario, and estimate the cost of introducing a population-based PSA screening program in the province. Methods A systematic literature search was performed to identify economic evaluations of population-based PSA screening strategies published from 1998 to 2013. Studies were assessed for their methodological quality and applicability to the Ontario setting. An original cost analysis was also performed, using data from Ontario administrative sources and from the published literature. One-year costs were estimated for 4 strategies: no screening, current (opportunistic) screening of men aged 40 years and older, current (opportunistic) screening of men aged 50 to 74 years, and population-based screening of men aged 50 to 74 years. The analysis was conducted from the payer perspective. Results The literature review demonstrated that, overall, population-based PSA screening is costly and cost-ineffective but may be cost-effective in specific populations. Only 1 Canadian study, published 15 years ago, was identified. Approximately $119.2 million is being spent annually on PSA screening of men aged 40 years and older in Ontario, including close to $22 million to screen men younger than 50 and older than 74 years of age (i.e., outside the target age range for a population-based program). A population-based screening program in Ontario would cost approximately $149.4 million in the first year. Limitations Estimates were based on the synthesis of data from a variety of sources, requiring several assumptions and causing uncertainty in the results. For example, where Ontario-specific data were unavailable, data from the United States were used. Conclusions PSA screening is associated with significant costs to the health care system when the cost of the PSA test itself is considered in addition to the costs of diagnosis, staging, and treatment of screen-detected PCs. PMID:26366237
Rose, Ray; Possingham, John
1976-01-01
Spinach seeds (Spinacia oleracea L.) given massive doses of γ-irradiation (500 krad) germinate and form a seedling with two green cotyledons and a radicle, but develop no further. Irradiated cotyledons show no increase in cell number or total DNA over a 7-day period in the light, while in control cotyledons there is a small increase in cell number and large increases in total DNA and chloroplast number. The chloroplasts of irradiated cotyledons are delayed in their division, become greatly enlarged and contain large amounts of starch. The whole population of chloroplasts subsequently undergoes a wave of division. The daughter chloroplasts show normal thylakoid development, but have some abnormal structural features caused by the radiation stress. Information on the effect of X-irradiation, ultraviolet irradiation, and 5-fluorodeoxyuridine on chloroplast replication and on chloroplast and nuclear DNA synthesis was obtained from cultured spinach leaf discs. It appears that chloroplast replication is more resistant to ionizing radiation than cell division and can proceed in the absence of nuclear DNA synthesis and greatly reduced chloroplast DNA synthesis. Images PMID:16659421
Alterations in protein metabolism during space flight and inactivity
NASA Technical Reports Server (NTRS)
Ferrando, Arny A.; Paddon-Jones, Doug; Wolfe, Robert R.
2002-01-01
Space flight and the accompanying diminished muscular activity lead to a loss of body nitrogen and muscle function. These losses may affect crew capabilities and health in long-duration missions. Space flight alters protein metabolism such that the body is unable to maintain protein synthetic rates. A concomitant hypocaloric intake and altered anabolic/catabolic hormonal profiles may contribute to or exacerbate this problem. The inactivity associated with bedrest also reduces muscle and whole-body protein synthesis. For this reason, bedrest provides a good model for the investigation of potential exercise and nutritional countermeasures to restore muscle protein synthesis. We have demonstrated that minimal resistance exercise preserves muscle protein synthesis throughout bedrest. In addition, ongoing work indicates that an essential amino acid and carbohydrate supplement may ameliorate the loss of lean body mass and muscle strength associated with 28 d of bedrest. The investigation of inactivity-induced alterations in protein metabolism, during space flight or prolonged bedrest, is applicable to clinical populations and, in a more general sense, to the problems associated with the decreased activity that occur with aging.
Population biology of the Florida manatee: An overview
O'Shea, Thomas J.; Ackerman, B.B.; O'Shea, Thomas J.; Ackerman, B.B.; Percival, H. Franklin
1995-01-01
In the following overview we discuss progress toward meeting the three objectives of the 1992 workshop: to provide a synthesis of existing information about manatee population biology; to evaluate the strengths and weaknesses of current data sets and approaches to research on manatee population biology; and to provide recommendations for research. We discuss progress in six topics that were assigned to working groups at the workshop: aerial survey and estimation of population size, reproduction, age structure, mortality, photoidentification and estimation of survival, and integration and modeling of population data. The overview includes recommendations by working group participants (*2 0'Shea et al. 1992). This workshop on manatee population biology was the most recent conference on the topic since 1978 (*BrowneIl and Rails 1981). Partly as a result of recommendations made at the 1978 workshop, several long-term population-related research projects were established. Therefore, we also measure progress in relation to knowledge available at the time of the earlier workshop. Finally, we provide a brief synopsis of pertinent new information on manatee population biology that became available between the 1992 workshop and publication of the proceedings and our conclusions about the status of the Florida manatee.
Murphy, D L; Sims, K; Eisenhofer, G; Greenberg, B D; George, T; Berlin, F; Zametkin, A; Ernst, M; Breakefield, X O
1998-01-01
Lack of monoamine oxidase A (MAO-A) due to either Xp chromosomal deletions or alterations in the coding sequence of the gene for this enzyme are associated with marked changes in monoamine metabolism and appear to be associated with variable cognitive deficits and behavioral changes in humans and in transgenic mice. In mice, some of the most marked behavioral changes are ameliorated by pharmacologically-induced reductions in serotonin synthesis during early development, raising the question of possible therapeutic interventions in humans with MAO deficiency states. At the present time, only one multi-generational family and a few other individuals with marked MAO-A deficiency states have been identified and studied in detail. Although MAO deficiency states associated with Xp chromosomal deletions were identified by distinct symptoms (including blindness in infancy) produced by the contiguous Norrie disease gene, the primarily behavioral phenotype of individuals with the MAO mutation is less obvious. This paper reports a sequential research design and preliminary results from screening several hundred volunteers in the general population and from putative high-risk groups for possible MAO deficiency states. These preliminary results suggest that marked MAO deficiency states are very rare.
Tracers of Stellar Mass-loss. II. Mid-IR Colors and Surface Brightness Fluctuations
NASA Astrophysics Data System (ADS)
González-Lópezlira, Rosa A.
2018-04-01
I present integrated colors and surface brightness fluctuation magnitudes in the mid-infrared (IR), derived from stellar population synthesis models that include the effects of the dusty envelopes around thermally pulsing asymptotic giant branch (TP-AGB) stars. The models are based on the Bruzual & Charlot CB* isochrones; they are single-burst, range in age from a few Myr to 14 Gyr, and comprise metallicities between Z = 0.0001 and Z = 0.04. I compare these models to mid-IR data of AGB stars and star clusters in the Magellanic Clouds, and study the effects of varying self-consistently the mass-loss rate, the stellar parameters, and the output spectra of the stars plus their dusty envelopes. I find that models with a higher than fiducial mass-loss rate are needed to fit the mid-IR colors of “extreme” single AGB stars in the Large Magellanic Cloud. Surface brightness fluctuation magnitudes are quite sensitive to metallicity for 4.5 μm and longer wavelengths at all stellar population ages, and powerful diagnostics of mass-loss rate in the TP-AGB for intermediate-age populations, between 100 Myr and 2–3 Gyr.
Statins and tendinopathy: a systematic review.
Teichtahl, Andrew J; Brady, Sharmayne R E; Urquhart, Donna M; Wluka, Anita E; Wang, Yuanyuan; Shaw, Jonathan E; Cicuttini, Flavia M
2016-02-15
To systematically review the evidence on whether statin therapy, commonly used in clinical practice to treat hypercholesterolaemia for primary and secondary prevention of cardiovascular disease, contributes to tendinopathy; and to examine causality according to the Bradford Hill criteria. A systematic review of studies examining the relationship between statin therapy and tendinopathy. Included studies were rated based on their methodological quality. A best evidence synthesis was used to summarise the results, and Bradford Hill criteria were used to assess causation. Ovid MEDLINE, CINAHL Plus, PubMed and Embase databases. We included adult human studies published in the English language between January 1966 and October 2015. Study designs eligible for inclusion were randomised controlled trials and cross-sectional, cohort or case-control studies. Four studies (three cohort studies and one case-control study) were included, with a mean methodological quality score of 67%. Three studies were deemed high quality. Tendon rupture was the primary outcome in three studies, and rotator cuff disease in the other. All studies found no positive association between statin therapy and tendon rupture for the total study population. There was evidence that simvastatin reduces the risk of tendinopathy. To date, there is a paucity of evidence to implicate statin therapy as a well established risk factor or causal mechanism for tendon rupture in the general population. There is strong evidence that simvastatin reduces the risk of tendinopathy.
Liu, Guang-Jian; He, Jian-Rong; Kuang, Ya-Shu; Fan, Xue-Jiao; Li, Wei-Dong; Lu, Jin-Hua; Xia, Xiao-Yan; Liu, Xiao-Dan; Chen, Nian-Nian; Mai, Wei-Bi; Xia, Hui-Min; Qiu, Xiu
2017-01-01
Preterm birth is the leading cause of mortality and morbidity in infants. Its etiology is multifactorial with genes and immune homeostasis. The authors investigated whether prostaglandin (PG) synthesis related single nucleotide polymorphisms (SNPs) PLA2G4C rs1366442 and PLA2G4D rs4924618 were associated with the risk of spontaneous preterm birth (SPTB) in a Chinese population of 114 cases of SPTB and 250 controls of term delivery. The risk associations were determined by odds ratios (ORs) and their 95% confidence intervals (CIs) calculated using multivariate logistic regression. Homology modeling was performed to elucidate potential mechanism of the SNP function. The maternal AT/TT genotype of PLA2G4D rs4924618 was associated with a reduced risk of SPTB (OR, 0.61; 95% CI, 0.37–0.99), while no significant association between PLA2G4C rs1366442 and SPTB risk was identified. Structure and sequence analysis revealed that the amino acid substitution introduced by this SNP located at the conserved central core of the catalytic domain of cytosolic phospholipase A2 δ and was close to the active site. These findings suggested that the polymorphism of PLA2G4D rs4924618 may have a protective influence on the SPTB susceptibility in a Chinese population, supporting a role for genetics in the association between PG synthesis and preterm birth. PMID:28440406
Neurological Diseases, Disorders and Injuries in Canada: Highlights of a National Study.
Bray, Garth M; Huggett, Deanna L
2016-01-01
The National Population Health Study of Neurological Conditions, a partnership between Neurological Health Charities Canada and the Government of Canada, was the largest study of neurological diseases, disorders, and injuries ever conducted in Canada. Undertaken between 2009 and 2013, the expansive program of research addressed the epidemiology, impacts, health services, and risk factors of 18 neurological conditions and estimated the health outcomes and costs of these conditions in Canada through 2031. This review summarizes highlights from the component projects of the study as presented in the synthesis report, Mapping Connections: An Understanding of Neurological Conditions in Canada. The key findings included new prevalence and incidence estimates, documentation of the diverse and often debilitating effects of neurological conditions, and identification of the utilization, economic costs, and current limitations of related health services. The study findings will support health charities, governments, and other stakeholders to reduce the impact of neurological conditions in Canada.
Antibiotics for PANDAS? Limited Evidence: Review and Putative Mechanisms of Action.
Burchi, Elisabetta; Pallanti, Stefano
2018-05-03
Antibiotics have been used extensively by clinicians to treat patients with PANDAS or PANS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections and pediatric acute-onset neuropsychiatric syndrome, respectively). This review examines the best-quality evidence supporting the practice-based use of antibiotics in these psychiatric conditions. PubMed was searched for English-language articles published between January 1994 and July 2017 using the search terms [PANDAS OR PANS OR new-onset pediatric OCD] AND [antibiotics OR macrolides OR beta-lactams]. Randomized clinical trials, observational studies, and case reports concerning antibiotic use in PANDAS/PANS were reviewed. Four publications were included in the quantitative synthesis. The evidence was rated using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) method. Although the single studies conveyed no statistically significant results, there is some evidence for efficacy of antibiotic therapy in reducing neuropsychiatric symptoms in the PANDAS/PANS population. Whereas the use of eradicating antibiotic therapy during active infections in PANDAS/PANS is well established, there is still a need for studies that improve the quality of evidence supporting use of antibiotics in this population independent of ongoing infections. Studies that compare antibiotics with other therapies, as well as studies that assess safety and efficacy of long-term use of antibiotic therapy in PANDAS/PANS, are still lacking. However, the available research supports evidence of a subgroup in the pediatric OCD population that is sensitive to antibiotic treatment and immunomodulatory therapy, independent of ongoing infectious conditions. Thus, more studies are warranted in the overall OCD spectrum. © Copyright 2018 Physicians Postgraduate Press, Inc.
Lim, Yuan Z; Wang, Yuanyuan; Wluka, Anita E; Davies-Tuck, Miranda L; Teichtahl, Andrew; Urquhart, Donna M; Cicuttini, Flavia M
2013-10-01
To systematically review the literature to determine whether biomechanical factors, meniscal pathology, and physical activity are risk factors for bone marrow lesions (BMLs) at the knee identified from magnetic resonance imaging in pre-osteoarthritis and osteoarthritis populations. Electronic searches of MEDLINE and EMBASE were performed from January 1, 1996 to October 31, 2012 using the keywords of bone marrow lesion(s), bone marrow (o)edema, osteoarthritis, and knee. Studies examining biomechanical factors, meniscal pathology, or physical activity in relation to the presence, incidence, or change in BMLs at the knee were included. Two independent reviewers extracted the data and assessed the methodological quality of selected studies. Due to the heterogeneity of the studies, we performed a best evidence synthesis. Fifteen studies were included in this review, of which 9 were considered high quality. The study populations were heterogeneous in terms of the symptoms and radiographic knee osteoarthritis. There was strong evidence for relationships of mechanical knee alignment and meniscal pathology with BMLs in osteoarthritis populations. There was a paucity of evidence for a relationship between physical activity and BMLs. Despite the heterogeneity of included studies, these data suggest that mechanical knee alignment and meniscal pathology are risk factors for BMLs in knee osteoarthritis. It suggests that BMLs in individuals with osteoarthritis are more susceptible to mechanical knee alignment. Given the role of BMLs in the pathogenesis of knee osteoarthritis, identifying strategies to modify these risk factors will be important in slowing the progression and reducing the burden of knee osteoarthritis. Copyright © 2013 Elsevier Inc. All rights reserved.
Singh, Kavita; Bjerregaard, Peter; Man Chan, Hing
2014-01-01
Background Since the 1990s, research has been carried out to monitor environmental contaminants and their effects on human health in the Arctic. Although evidence shows that Arctic indigenous peoples are exposed to higher levels of contaminants and do worse on several dimensions of health compared with other populations, the contribution of such exposures on adverse outcomes is unclear. Objective The purpose of this review is to provide a synopsis of the published epidemiological literature that has examined association between environmental contaminants and health outcomes in Arctic indigenous populations. Design A literature search was conducted in OVID Medline (1946-January 2014) using search terms that combined concepts of contaminant and indigenous populations in the Arctic. No language or date restrictions were applied. The reference lists of review articles were hand-searched. Results Of 559 citations, 60 studies were relevant. The studies fell under the following categories: paediatric (n=18), reproductive health (n=18), obstetrics and gynaecology (n=9), cardiology (n=7), bone health (n=2), oncology (n=2), endocrinology (n=2) and other (n=2). All studies, except one from Arctic Finland, were either from Nunavik or Greenland. Most studies assessed polychlorinated biphenyls (n=43) and organochlorine pesticides (n=29). Fewer studies examined heavy metals, perfluorinated compounds, or polybrominated diphenyl ethers. Details of study results for each health category are provided. Conclusions It is difficult to make conclusive statements about the effects of environmental contaminants on health due to mixed results, small number of studies and studies being restricted to a small number of regions. Meta-analytical synthesis of the evidence should be considered for priority contaminants and health outcomes. The following research gaps should be addressed in future studies: association of contaminants and health in other Arctic regions (i.e. Inuvialuit Settlement Region, Nunavut, Nunatsiavut, Alaska, European North and Russian North); assessment of contaminants on chronic diseases; inclusion of clinical endpoints in assessments; and assessment of the emerging contaminants of perfluorinated compounds and polybrominated diphenyl ethers.
Singh, Kavita; Bjerregaard, Peter; Chan, Hing Man
2014-01-01
Since the 1990s, research has been carried out to monitor environmental contaminants and their effects on human health in the Arctic. Although evidence shows that Arctic indigenous peoples are exposed to higher levels of contaminants and do worse on several dimensions of health compared with other populations, the contribution of such exposures on adverse outcomes is unclear. The purpose of this review is to provide a synopsis of the published epidemiological literature that has examined association between environmental contaminants and health outcomes in Arctic indigenous populations. A literature search was conducted in OVID Medline (1946-January 2014) using search terms that combined concepts of contaminant and indigenous populations in the Arctic. No language or date restrictions were applied. The reference lists of review articles were hand-searched. Of 559 citations, 60 studies were relevant. The studies fell under the following categories: paediatric (n=18), reproductive health (n=18), obstetrics and gynaecology (n=9), cardiology (n=7), bone health (n=2), oncology (n=2), endocrinology (n=2) and other (n=2). All studies, except one from Arctic Finland, were either from Nunavik or Greenland. Most studies assessed polychlorinated biphenyls (n=43) and organochlorine pesticides (n=29). Fewer studies examined heavy metals, perfluorinated compounds, or polybrominated diphenyl ethers. Details of study results for each health category are provided. It is difficult to make conclusive statements about the effects of environmental contaminants on health due to mixed results, small number of studies and studies being restricted to a small number of regions. Meta-analytical synthesis of the evidence should be considered for priority contaminants and health outcomes. The following research gaps should be addressed in future studies: association of contaminants and health in other Arctic regions (i.e. Inuvialuit Settlement Region, Nunavut, Nunatsiavut, Alaska, European North and Russian North); assessment of contaminants on chronic diseases; inclusion of clinical endpoints in assessments; and assessment of the emerging contaminants of perfluorinated compounds and polybrominated diphenyl ethers.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Murton, Jaclyn; Nagarajan, Aparna; Nguyen, Amelia Y.
Cyanobacterial phycobilisome (PBS) pigment-protein complexes harvest light and transfer the energy to reaction centers. Previous ensemble studies have shown that cyanobacteria respond to changes in nutrient availability by modifying the structure of PBS complexes, but this process has not been visualized for individual pigments at the single-cell level due to spectral overlap. We characterized the response of four key photosynthetic pigments to nitrogen depletion and repletion at the subcellular level in individual, live Synechocystis sp. PCC 6803 cells using hyperspectral confocal fluorescence microscopy and multivariate image analysis. Our results revealed that PBS degradation and re-synthesis comprise a rapid response tomore » nitrogen fluctuations, with coordinated populations of cells undergoing pigment modifications. Chlorophyll fluorescence originating from photosystem I and II decreased during nitrogen starvation, but no alteration in subcellular chlorophyll localization was found. Lastly, we observed differential rod and core pigment responses to nitrogen deprivation, suggesting that PBS complexes undergo a stepwise degradation process.« less
Murton, Jaclyn; Nagarajan, Aparna; Nguyen, Amelia Y.; ...
2017-07-21
Cyanobacterial phycobilisome (PBS) pigment-protein complexes harvest light and transfer the energy to reaction centers. Previous ensemble studies have shown that cyanobacteria respond to changes in nutrient availability by modifying the structure of PBS complexes, but this process has not been visualized for individual pigments at the single-cell level due to spectral overlap. We characterized the response of four key photosynthetic pigments to nitrogen depletion and repletion at the subcellular level in individual, live Synechocystis sp. PCC 6803 cells using hyperspectral confocal fluorescence microscopy and multivariate image analysis. Our results revealed that PBS degradation and re-synthesis comprise a rapid response tomore » nitrogen fluctuations, with coordinated populations of cells undergoing pigment modifications. Chlorophyll fluorescence originating from photosystem I and II decreased during nitrogen starvation, but no alteration in subcellular chlorophyll localization was found. Lastly, we observed differential rod and core pigment responses to nitrogen deprivation, suggesting that PBS complexes undergo a stepwise degradation process.« less
Hood-Nowotny, Rebecca; Schwarzinger, Bettina; Schwarzinger, Clemens; Soliban, Sharon; Madakacherry, Odessa; Aigner, Martina; Watzka, Margarete; Gilles, Jeremie
2012-01-01
Background Knowing the underlying mechanisms of mosquito ecology will ensure effective vector management and contribute to the overall goal of malaria control. Mosquito populations show a high degree of population plasticity in response to environmental variability. However, the principle factors controlling population size and fecundity are for the most part unknown. Larval habitat and diet play a crucial role in subsequent mosquito fitness. Developing the most competitive insects for sterile insect technique programmes requires a “production” orientated perspective, to deduce the most effective larval diet formulation; the information gained from this process offers us some insight into the mechanisms and processes taking place in natural native mosquito habitats. Methodology/Principal Findings Fatty acid profiles and de-novo or direct assimilation pathways, of whole-individual mosquitoes reared on a range of larval diets were determined using pyrolysis gas chromatograph/mass spectrometry. We used elemental analysis and isotope ratio mass spectrometry to measure individual-whole-body carbon, nitrogen and phosphorous values and to assess the impact of dietary quality on subsequent population stoichiometry, size, quality and isotopic signature. Diet had the greatest impact on fatty acid (FA) profiles of the mosquitoes, which exhibited a high degree of dietary routing, characteristic of generalist feeders. De-novo synthesis of a number of important FAs was observed. Mosquito C:N stoichiometry was fixed in the teneral stage. Dietary N content had significant influence on mosquito size, and P was shown to be a flexible pool which limited overall population size. Conclusions/Significance Direct routing of FAs was evident but there was ubiquitous de-novo synthesis suggesting mosquito larvae are competent generalist feeders capable of survival on diet with varying characteristics. It was concluded that nitrogen availability in the larval diet controlled teneral mosquito size and that teneral CN ratio is a sex- and species-specific fixed parameter. This finding has significant implications for overall mosquito competitiveness and environmental management. PMID:23133509