Theoretical and experimental α decay half-lives of the heaviest odd-Z elements and general predictions

NASA Astrophysics Data System (ADS)

Zhang, H. F.; Royer, G.

2007-10-01

Theoretical α decay half-lives of the heaviest odd-Z nuclei are calculated using the experimental Qα value. The barriers in the quasimolecular shape path are determined within a Generalized Liquid Drop Model (GLDM) and the WKB approximation is used. The results are compared with calculations using the Density-Dependent M3Y (DDM3Y) effective interaction and the Viola-Seaborg-Sobiczewski (VSS) formulas. The calculations provide consistent estimates for the half-lives of the α decay chains of these superheavy elements. The experimental data stand between the GLDM calculations and VSS ones in the most time. Predictions are provided for the α decay half-lives of other superheavy nuclei within the GLDM and VSS approaches using the recent extrapolated Qα of Audi, Wapstra, and Thibault [Nucl. Phys. A729, 337 (2003)], which may be used for future experimental assignment and identification.

Topology and Oligomerization of Mono- and Oligomeric Proteins Regulate Their Half-Lives in the Cell.

PubMed

Mallik, Saurav; Kundu, Sudip

2018-06-05

To find additional structural constraints (besides disordered segments) that regulate protein half-life in the cell, we herein assess the influence of native topology of monomeric and sequestration of oligomeric proteins into multimeric complexes in yeast, human, and mouse. Native topology acts as a molecular marker of globular protein's mechanical resistance and consequently captures their half-life variations on genome scale. Sequestration into multimeric complexes elongates oligomeric protein half-life in the cell, presumably by burying ubiquitinoylation sites and disordered segments required for proteasomal recognition. The latter effect is stronger for proteins associated with multiple complexes and for those binding early during complex self-assembly, including proteins that oligomerize with large proportions of surface buried. After gene duplication, diversification of topology and sequestration into non-identical sets of complexes alter half-lives of paralogous proteins during the course of evolution. Thus, native topology and sequestration into multimeric complexes reflect designing principles of proteins to regulate their half-lives. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Next Big Thing We Won't Be Able to Live Without? Fulbright's Half-Life Theory Gives Us Some Ideas

ERIC Educational Resources Information Center

Fulbright, Ron

2015-01-01

My great-grandparents lived one-half of their lives without electricity. My grandparents lived one-half of their lives without a telephone. My parents lived one-half of their lives without a television. My sister has lived one-half of her life without a computer and I have lived one-half of my life without Google. Today, we could not imagine life…

Theoretical and experimental {alpha} decay half-lives of the heaviest odd-Z elements and general predictions

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

Zhang, H. F.; Royer, G.

Theoretical {alpha} decay half-lives of the heaviest odd-Z nuclei are calculated using the experimental Q{sub {alpha}} value. The barriers in the quasimolecular shape path are determined within a Generalized Liquid Drop Model (GLDM) and the WKB approximation is used. The results are compared with calculations using the Density-Dependent M3Y (DDM3Y) effective interaction and the Viola-Seaborg-Sobiczewski (VSS) formulas. The calculations provide consistent estimates for the half-lives of the {alpha} decay chains of these superheavy elements. The experimental data stand between the GLDM calculations and VSS ones in the most time. Predictions are provided for the {alpha} decay half-lives of other superheavymore » nuclei within the GLDM and VSS approaches using the recent extrapolated Q{sub {alpha}} of Audi, Wapstra, and Thibault [Nucl. Phys. A729, 337 (2003)], which may be used for future experimental assignment and identification.« less

Half-lives of α -decaying nuclei in the medium-mass region within the transfer matrix method

NASA Astrophysics Data System (ADS)

Wu, Shuangxiang; Qian, Yibin; Ren, Zhongzhou

2018-05-01

The α -decay half-lives of even-even nuclei from Sm to Th are systematically studied based on the transfer matrix method. For the nuclear potential, a type of cosh-parametrized form is applied to calculate the penetration probability. Through a least-squares fit to experimental half-lives, we optimize the parameters in the potential and the α preformation factor P0. During this process, P0 is treated as a constant for each parent nucleus. Eventually, the calculated half-lives are found to agree well with the experimental data, which verifies the accuracy of the present approach. Furthermore, in recent studies, P0 is regulated by the shell and paring effects plus the nuclear deformation. To this end, P0 is here associated with the structural quantity, i.e., the microscopic correction of nuclear mass (Emic). In this way, the agreement between theory and experiment is greatly improved by more than 20%, validating the appropriate treatment of P0 in the scheme of Emic.

Beta-decay half-lives for short neutron rich nuclei involved into the r-process

NASA Astrophysics Data System (ADS)

Panov, I.; Lutostansky, Yu; Thielemann, F.-K.

2018-01-01

The beta-strength function model based on Finite Fermi-Systems Theory is applied for calculations of the beta-decay half-lives for short neutron rich nuclei involved into the r- process. It is shown that the accuracy of beta-decay half-lives of short-lived neutron-rich nuclei is improving with increasing neutron excess and can be used for modeling of nucleosynthesis of heavy nuclei in the r-process.

The generalized liquid drop model alpha-decay formula: Predictability analysis and superheavy element alpha half-lives

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

Dasgupta-Schubert, N.; Reyes, M.A.

2007-11-15

The predictive accuracy of the generalized liquid drop model (GLDM) formula for alpha-decay half-lives has been investigated in a detailed manner and a variant of the formula with improved coefficients is proposed. The method employs the experimental alpha half-lives of the well-known alpha standards to obtain the coefficients of the analytical formula using the experimental Q{sub {alpha}} values (the DSR-E formula), as well as the finite range droplet model (FRDM) derived Q{sub {alpha}} values (the FRDM-FRDM formula). The predictive accuracy of these formulae was checked against the experimental alpha half-lives of an independent set of nuclei (TEST) that span approximatelymore » the same Z, A region as the standards and possess reliable alpha spectroscopic data, and were found to yield good results for the DSR-E formula but not for the FRDM-FRDM formula. The two formulae were used to obtain the alpha half-lives of superheavy elements (SHE) and heavy nuclides where the relative accuracy was found to be markedly improved for the FRDM-FRDM formula, which corroborates the appropriateness of the FRDM masses and the GLDM prescription for high Z, A nuclides. Further improvement resulted, especially for the FRDM-FRDM formula, after a simple linear optimization over the calculated and experimental half-lives of TEST was used to re-calculate the half-lives of the SHE and heavy nuclides. The advantage of this optimization was that it required no re-calculation of the coefficients of the basic DSR-E or FRDM-FRDM formulae. The half-lives for 324 medium-mass to superheavy alpha decaying nuclides, calculated using these formulae and the comparison with experimental half-lives, are presented.« less

Evaluating the environmental parameters that determine aerobic biodegradation half-lives of pesticides in soil with a multivariable approach.

PubMed

Wang, Yuxin; Lai, Adelene; Latino, Diogo; Fenner, Kathrin; Helbling, Damian E

2018-06-14

Aerobic biodegradation half-lives (half-lives) are key parameters used to evaluate pesticide persistence in soil. However, half-life estimates for individual pesticides often span several orders of magnitude, reflecting the impact that various environmental or experimental parameters have on half-lives in soil. In this work, we collected literature-reported half-lives for eleven pesticides along with associated metadata describing the environmental or experimental conditions under which they were derived. We then developed a multivariable framework to discover relationships between the half-lives and associated metadata. We first compared data for the herbicide atrazine collected from 95 laboratory and 65 field studies. We discovered that atrazine application history and soil texture were the parameters that have the largest influence on the observed half-lives in both types of studies. We then extended the analysis to include ten additional pesticides with data collected exclusively from laboratory studies. We found that, when data were available, pesticide application history and biomass concentrations were always positively associated with half-lives. The relevance of other parameters varied among the pesticides, but in some cases the variability could be explained by the physicochemical properties of the pesticides. For example, we found that the relative significance of the organic carbon content of soil for determining half-lives depends on the relative solubility of the pesticide. Altogether, our analyses highlight the reciprocal influence of both environmental parameters and intrinsic physicochemical properties for determining half-lives in soil. Copyright © 2018 Elsevier Ltd. All rights reserved.

The predictive accuracy of analytical formulas and semiclassical approaches for α decay half-lives of superheavy nuclei

NASA Astrophysics Data System (ADS)

Zhao, T. L.; Bao, X. J.; Guo, S. Q.

2018-02-01

Systematic calculations on the α decay half-lives are performed by using three analytical formulas and two semiclassical approaches. For the three analytical formulas, the experimental α decay half-lives and {Q}α values of the 66 reference nuclei have been used to obtain the coefficients. We get only four adjustable parameters to describe α decay half-lives for even-even, odd-A, and odd-odd nuclei. By comparison between the calculated values from ten analytical formulas and experimental data, it is shown that the new universal decay law (NUDL) foumula is the most accurate one to reproduce the experimental α decay half-lives of the superheavy nuclei (SHN). Meanwhile it is found that the experimental α decay half-lives of SHN are well reproduced by the Royer formula although many parameters are contained. The results show that the NUDL formula and the generalized liquid drop model (GLDM2) with consideration of the preformation factor can give fairly equivalent results for the superheavy nuclei.

Occurrence, temporal trends, and half-lives of perfluoroalkyl acids (PFAAs) in occupational workers in China

NASA Astrophysics Data System (ADS)

Fu, Jianjie; Gao, Yan; Cui, Lin; Wang, Thanh; Liang, Yong; Qu, Guangbo; Yuan, Bo; Wang, Yawei; Zhang, Aiqian; Jiang, Guibin

2016-12-01

Paired serum and urine samples were collected from workers in a fluorochemical plant from 2008 to 2012 (n = 302) to investigate the level, temporal trends, and half-lives of PFAAs in workers of a fluorochemical plant. High levels of perfluorohexane sulfonate (PFHxS), perfluorooctanoic acid (PFOA), and perfluorooctanesulfonate (PFOS) were detected in serum with median concentrations of 764, 427, and 1725 ng mL-1, respectively. The half-lives of PFAAs in workers were estimated by daily clearance rates and annual decline rates of PFAAs in serum by a first-order model. The geometric mean and median value for PFHxS, PFOA, and PFOS were 14.7 and 11.7, 4.1 and 4.0, 32.6 and 21.6 years, respectively, by the daily clearance rates, and they were 3.6, 1.7, and 1.9 years estimated by annual decline rates. The half-lives estimated by the limited clearance route information could be considered as the upper limits for PFAAs, however, the huge difference between two estimated approaches indicated that there were other important elimination pathways of PFAAs other than renal clearance in human. The half-lives estimated by annual decline rates in the present study were the shortest values ever reported, and the intrinsic half-lives might even shorter due to the high levels of ongoing exposure to PFAAs.

Occurrence, temporal trends, and half-lives of perfluoroalkyl acids (PFAAs) in occupational workers in China

PubMed Central

Fu, Jianjie; Gao, Yan; Cui, Lin; Wang, Thanh; Liang, Yong; Qu, Guangbo; Yuan, Bo; Wang, Yawei; Zhang, Aiqian; Jiang, Guibin

2016-01-01

Paired serum and urine samples were collected from workers in a fluorochemical plant from 2008 to 2012 (n = 302) to investigate the level, temporal trends, and half-lives of PFAAs in workers of a fluorochemical plant. High levels of perfluorohexane sulfonate (PFHxS), perfluorooctanoic acid (PFOA), and perfluorooctanesulfonate (PFOS) were detected in serum with median concentrations of 764, 427, and 1725 ng mL−1, respectively. The half-lives of PFAAs in workers were estimated by daily clearance rates and annual decline rates of PFAAs in serum by a first-order model. The geometric mean and median value for PFHxS, PFOA, and PFOS were 14.7 and 11.7, 4.1 and 4.0, 32.6 and 21.6 years, respectively, by the daily clearance rates, and they were 3.6, 1.7, and 1.9 years estimated by annual decline rates. The half-lives estimated by the limited clearance route information could be considered as the upper limits for PFAAs, however, the huge difference between two estimated approaches indicated that there were other important elimination pathways of PFAAs other than renal clearance in human. The half-lives estimated by annual decline rates in the present study were the shortest values ever reported, and the intrinsic half-lives might even shorter due to the high levels of ongoing exposure to PFAAs. PMID:27905562

Ecological Consciousness of a Personality Living in an Ecologically Unfavorable Region

ERIC Educational Resources Information Center

Jumazhanova, Gulzhanar; Tursungozhinova, Gulnar; Belenko, Oxana; Iskakova, Marzhan; Amanova, Aray

2016-01-01

This article covers on the matters which allow stating that people living in the areas with unfavorable ecological conditions experience long-term psycho-traumatic psychological stress caused by exaggeration of irradiation danger and its aftereffects for health. The reasons for long-term psychological stress as per the results of questionnaire and…

Half-lives of 101Rh g and 108Ag m

DOE PAGES

Shugart, Howard A.; Browne, Edgardo; Norman, Eric B.

2018-02-20

Using long-term gamma-ray spectroscopy with high resolution germanium detectors and a ratio method, the half-lives of 101Rh g and 108Ag m have been determined to be 4.07 ± 0.05 years and 448 ± 27 years, respectively. These results are then compared with previously reported values.

Half-lives of 101Rh g and 108Ag m

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

Shugart, Howard A.; Browne, Edgardo; Norman, Eric B.

Using long-term gamma-ray spectroscopy with high resolution germanium detectors and a ratio method, the half-lives of 101Rh g and 108Ag m have been determined to be 4.07 ± 0.05 years and 448 ± 27 years, respectively. These results are then compared with previously reported values.

Half-lives of 101 Rh g and 108 Ag m

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

Shugart, H.; Browne, E.; Norman, E.

Using long-term gamma-ray spectroscopy with high resolution germanium detectors and a ratio method, the half-lives of 101Rhg and 108Agm have been determined to be 4.07 ± 0.05 years and 448 ± 27 years, respectively. These results are compared with previously reported values.

Do radioactive half-lives vary with the Earth-to-Sun distance?

PubMed

Hardy, J C; Goodwin, J R; Iacob, V E

2012-09-01

Recently, Jenkins, Fischbach and collaborators have claimed evidence that radionuclide half-lives vary systematically over a ±0.1% range as a function of the oscillating distance between the Earth and the Sun, based on multi-year activity measurements. We have avoided the time-dependent instabilities to which such measurements are susceptible by directly measuring the half-life of (198)Au (t(1/2)=2.695 d) on seven occasions spread out in time to cover the complete range of Earth-Sun distances. We observe no systematic oscillations in half-life and can set an upper limit on their amplitude of ±0.02%. Copyright © 2012 Elsevier Ltd. All rights reserved.

Systematic study of α-decay half-lives using Royer and related formula

NASA Astrophysics Data System (ADS)

Akrawy, Dashty T.; Hassanabadi, H.; Hosseini, S. S.; Santhosh, K. P.

2018-03-01

The alpha decay half-lives of 356 isotopes were studied using the Royer and related Formula and are compared with experimental data. The study shows that the predicted half-lives match well with experimental data over a wide range for each (Z , N) parity of the parent nuclei. We have calculated the standard deviation of log10 ⁡Tα (s), for each formula and our study indicate that, for alpha decay studies, generally, analytical ℓ-dependent formula proposed by Royer, with σRB = 0.4373, is the best model followed by the formula proposed by Denisov and Khudenko (DK), σDK = 0.4743 for all 356 nuclei. We hope the present study is a clear indicator of the predictive power of Royer and related formula.

Calculated half-lives and kinetic energies for spontaneous emission of heavy ions from nuclei

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

Poenaru, D.N.; Greiner, W.; Depta, K.

The most probable decays by spontaneous emission of heavy ions are listed for nuclides with Z = 47--106 and total half-lives>1 ..mu..sec. Partial half-lives, branching ratios relative to ..cap alpha.. decay, kinetic energies, and Q values are estimated by using the analytical superasymmetric fission model, a semiempirical formula for those ..cap alpha..-decay lifetimes which have not been measured, and the new Wapstra--Audi mass tables. Numerous ''stable'' nuclides with Z>40 are found to be metastable with respect to the new decay modes. The current experimental status is briefly reviewed.

Half-Lives of Proton Emitters With a Deformed Density-Dependent Model

NASA Astrophysics Data System (ADS)

Qian, Yi-Bin; Ren, Zhong-Zhou; Ni, Dong-Dong; Sheng, Zong-Qiang

2010-11-01

Half-lives of proton radioactivity are investigated with a deformed density-dependent model. The single folding potential which is dependent on deformation and orientation is employed to calculate the proton decay width through the deformed potential barrier. In addition, the spectroscopic factor is taken into account in the calculation, which is obtained in the relativistic mean field theory with NL3. The calculated results of semi-spherical nuclei are found to be in good agreement with the experimental data, and the results of well-deformed nuclei are also satisfactory. Moreover, a formula for the spherical proton emission half-life based on the Gamow quantum tunneling theory is presented.

Intermittent Drug Dosing Intervals Guided by the Operational Multiple Dosing Half Lives for Predictable Plasma Accumulation and Fluctuation

PubMed Central

Grover, Anita; Benet, Leslie Z.

2013-01-01

Intermittent drug dosing intervals are usually initially guided by the terminal pharmacokinetic half life and are dependent on drug formulation. For chronic multiple dosing and for extended release dosage forms, the terminal half life often does not predict the plasma drug accumulation or fluctuation observed. We define and advance applications for the operational multiple dosing half lives for drug accumulation and fluctuation after multiple oral dosing at steady-state. Using Monte Carlo simulation, our results predict a way to maximize the operational multiple dosing half lives relative to the terminal half life by using a first-order absorption rate constant close to the terminal elimination rate constant in the design of extended release dosage forms. In this way, drugs that may be eliminated early in the development pipeline due to a relatively short half life can be formulated to be dosed at intervals three times the terminal half life, maximizing compliance, while maintaining tight plasma concentration accumulation and fluctuation ranges. We also present situations in which the operational multiple dosing half lives will be especially relevant in the determination of dosing intervals, including for drugs that follow a direct PKPD model and have a narrow therapeutic index, as the rate of concentration decrease after chronic multiple dosing (that is not the terminal half life) can be determined via simulation. These principles are illustrated with case studies on valproic acid, diazepam, and anti-hypertensives. PMID:21499748

Urban ecological restoration (Introduction to a special theme issue)

Treesearch

Paul H. Gobster

2010-01-01

What does ecological restoration mean in an urban context? More than half of the world's population now lives in cities, and in response to the dynamic patterns of urbanization, a growing number of ecologists, land managers, and volunteers are focusing their efforts in and around cities to restore remnants of natural diversity (Ingram 2008). Ecological restoration...

Relationship among aqueous copper half-lives and responses of Pimephales promelas to a series of copper sulfate pentahydrate concentrations.

PubMed

Calomeni, Alyssa J; Kinley, Ciera M; Geer, Tyler D; Iwinski, Kyla J; Hendrikse, Maas; Rodgers, John H

2018-04-01

Copper algaecide exposures in situ are often of shorter duration than exposures for static toxicity experiments because aqueous concentrations in situ dissipate as a function of site-specific fate processes. Consequently, responses of organisms to static copper exposures may overestimate effects following in situ exposures. To understand the role of exposure duration for altering responses, Pimephales promelas survival was compared following static (96 h) and pulse (1.5, 4, 8, and 15 h half-lives) exposures of CuSO 4 •5H 2 O. Copper concentrations sorbed by fry indicated a consequence of different exposures. Responses of P. promelas to static exposures resulted in 96 h LC 50 s of 166 µgCu/L (95% confidence interval [CI], 142-189 µgCu/L) as soluble copper and 162 µgCu/L (CI, 140-183 µgCu/L) as acid soluble copper. Relative to static 96 h LC 50 s, exposures with half-lives of 1.5, 4 and 8 h resulted in LC 50 s 10, 3 and 2 times greater, respectively, for responses measured 96 h after exposure initiation. Copper concentrations extracted from fry exposed for 1.5, 4 and 8 h half-lives were less than the static experiment. However, copper sorbed by fry in the 15 h half-life experiment was not different than the static experiment. The relationship between 96 h LC 50 and 1/half-life was expressed using the equations y = 116 + 1360 × (R 2  = 0.97) for soluble copper and y = 147 + 1620 × (R 2  = 0.98) for acid soluble copper. Incorporation of exposure duration for predictions of P. promelas responses to copper pulse exposures increases prediction accuracy by an order of magnitude.

Living in interesting times: Selected implications of landscape ecology for conservation science

Treesearch

John Shultis

2007-01-01

The phrase ‘May you live in interesting times’ links well with the sub-discipline of landscape ecology. Recent research in landscape ecology and associated disciplines (for example, conservation biology) provides significant challenges to the traditional conceptions of wilderness and conservation science, and may in part reflect upon our view of contemporary society as...

NUCLEAR AND HEAVY ION PHYSICS: α-decay half-lives of superheavy nuclei and general predictions

NASA Astrophysics Data System (ADS)

Dong, Jian-Min; Zhang, Hong-Fei; Wang, Yan-Zhao; Zuo, Wei; Su, Xin-Ning; Li, Jun-Qing

2009-08-01

The generalized liquid drop model (GLDM) and the cluster model have been employed to calculate the α-decay half-lives of superheavy nuclei (SHN) using the experimental α-decay Q values. The results of the cluster model are slightly poorer than those from the GLDM if experimental Q values are used. The prediction powers of these two models with theoretical Q values from Audi et al. (QAudi) and Muntian et al. (QM) have been tested to find that the cluster model with QAudi and QM could provide reliable results for Z > 112 but the GLDM with QAudi for Z <= 112. The half-lives of some still unknown nuclei are predicted by these two models and these results may be useful for future experimental assignment and identification.

β-Decay Half-Lives of Co76,77, Ni79,80, and Cu81: Experimental Indication of a Doubly Magic Ni78

NASA Astrophysics Data System (ADS)

Xu, Z. Y.; Nishimura, S.; Lorusso, G.; Browne, F.; Doornenbal, P.; Gey, G.; Jung, H.-S.; Li, Z.; Niikura, M.; Söderström, P.-A.; Sumikama, T.; Taprogge, J.; Vajta, Zs.; Watanabe, H.; Wu, J.; Yagi, A.; Yoshinaga, K.; Baba, H.; Franchoo, S.; Isobe, T.; John, P. R.; Kojouharov, I.; Kubono, S.; Kurz, N.; Matea, I.; Matsui, K.; Mengoni, D.; Morfouace, P.; Napoli, D. R.; Naqvi, F.; Nishibata, H.; Odahara, A.; Şahin, E.; Sakurai, H.; Schaffner, H.; Stefan, I. G.; Suzuki, D.; Taniuchi, R.; Werner, V.

2014-07-01

The half-lives of 20 neutron-rich nuclei with Z =27-30 have been measured at the RIBF, including five new half-lives of Co76(21.7-4.9+6.5 ms), Co77(13.0-4.3+7.2 ms), Ni79(43.0-7.5+8.6 ms), Ni80(23.9-17.2+26.0 ms), and Cu81(73.2±6.8 ms). In addition, the half-lives of Co73-75, Ni74-78, Cu78-80, and Zn80-82 were determined with higher precision than previous works. Based on these new results, a systematic study of the β-decay half-lives has been carried out, which suggests a sizable magicity for both the proton number Z =28 and the neutron number N=50 in Ni78.

Nesting and acoustic ecology, but not phylogeny, influence passerine urban tolerance.

PubMed

Cardoso, Gonçalo C

2014-03-01

Urbanization is one of the most extensive and ecologically significant changes happening to terrestrial environments, as it strongly affects the distribution of biodiversity. It is well established that native species richness is reduced in urban and suburban areas, but the species traits that predict tolerance to urbanization are yet little understood. In birds, one of the most studied groups in this respect, evidence is appearing that acoustic traits influence urban living, but it remains unknown how this compares to the effects of more obvious ecological traits that facilitate urban living. Therefore, it remains unclear whether acoustic communication is an important predictor of urban tolerance among species. Here, with a comparative study across 140 European and North American passerines, I show that high song frequency, which is less masked by the low-frequency anthropogenic noise, is associated with urban tolerance, with an effect size over half that of the most important ecological trait studied: off-ground nesting. Other nesting and foraging traits accepted to facilitate urban living did not differ for species occurring in urban environments. Thus, the contribution of acoustic traits for passerine urban tolerance approximates that of more obvious ecological traits. Nonetheless, effect sizes of the biological predictors of urban tolerance were low and the phylogenetic signal for urban tolerance was null, both of which suggest that factors other than phenotypic traits have major effects on urban tolerance. A simple possibility is exposure to urbanization, as there was a higher proportion of urban-tolerant species in Europe, which is more urbanized than North America. © 2013 John Wiley & Sons Ltd.

Resilience amongst Older Colombians Living in Poverty: an Ecological Approach.

PubMed

Bennett, Kate M; Reyes-Rodriguez, Maria F; Altamar, Paula; Soulsby, Laura K

2016-12-01

Older Colombians face significant adversities: poverty, violence and displacement. However, there is evidence that Latinos are often resilient. We examine resilience in older Colombians living in poverty using an ecological framework that identifies three levels: individual; community; and societal. In this paper we examine data from 16 semi-structured interviews with older Colombians that explore resilience within the context of poverty. We analyze our data using three stages: (1) modified grounded theory; (2) assignment of resilience status; (3) identification of components of the ecological framework which contribute to resilience in these participants. The most striking feature is that some participants are able to adapt to their situation, demonstrating resilience, whilst others are not. Individual characteristics such as psychological and material resources contribute to resilience. At the community level, family, social support, participation and cohesion promote resilience. Finally, at the societal level, social and welfare services, finance, religion and social policy, are important factors. These different levels of resilience are co-dependent, and we illustrate how this is so. We suggest that older Colombians living in poverty often demonstrate resilience, but that more can be done to enhance their lives. This includes interventions at the individual and community levels alongside changes in social policy.

A review of ecological effects and environmental fate of illicit drugs in aquatic ecosystems.

PubMed

Rosi-Marshall, E J; Snow, D; Bartelt-Hunt, S L; Paspalof, A; Tank, J L

2015-01-23

Although illicit drugs are detected in surface waters throughout the world, their environmental fate and ecological effects are not well understood. Many illicit drugs and their breakdown products have been detected in surface waters and temporal and spatial variability in use translates into "hot spots and hot moments" of occurrence. Illicit drug occurrence in regions of production and use and areas with insufficient wastewater treatment are not well studied and should be targeted for further study. Evidence suggests that illicit drugs may not be persistent, as their half-lives are relatively short, but may exhibit "pseudo-persistence" wherein continual use results in persistent occurrence. We reviewed the literature on the ecological effects of these compounds on aquatic organisms and although research is limited, a wide array of aquatic organisms, including bacteria, algae, invertebrates, and fishes, have receptors that make them potentially sensitive to these compounds. In summary, illicit drugs occur in surface waters and aquatic organisms may be affected by these compounds; research is needed that focuses on concentrations of illicit drugs in areas of production and high use, environmental fate of these compounds, and effects of these compounds on aquatic ecosystems at the concentrations that typically occur in the environment. Copyright © 2014 Elsevier B.V. All rights reserved.

Ecological drivers of group living in two populations of the communally rearing rodent, Octodon degus

PubMed Central

Sobrero, Raúl; Quirici, Verónica; Castro, Rodrigo A.; Tolhuysen, Liliana Ortiz; Vargas, Francisco; Burger, Joseph Robert; Quispe, René; Villavicencio, Camila P.; Vásquez, Rodrigo A.; Hayes, Loren D.

2012-01-01

Intraspecific variation in sociality is thought to reflect a trade-off between current fitness benefits and costs that emerge from individuals' decision to join or leave groups. Since those benefits and costs may be influenced by ecological conditions, ecological variation remains a major, ultimate cause of intraspecific variation in sociality. Intraspecific comparisons of mammalian sociality across populations facing different environmental conditions have not provided a consistent relationship between ecological variation and group-living. Thus, we studied two populations of the communally rearing rodent Octodon degus to determine how co-variation between sociality and ecology supports alternative ecological causes of group living. In particular, we examined how variables linked to predation risk, thermal conditions, burrowing costs, and food availability predicted temporal and population variation in sociality. Our study revealed population and temporal variation in total group size and group composition that covaried with population and yearly differences in ecology. In particular, predation risk and burrowing costs are supported as drivers of this social variation in degus. Thermal differences, food quantity and quality were not significant predictors of social group size. In contrast to between populations, social variation within populations was largely uncoupled from ecological differences. PMID:22344477

Discordance between living and death assemblages as evidence for anthropogenic ecological change

PubMed Central

Kidwell, Susan M.

2007-01-01

Mismatches between the composition of a time-averaged death assemblage (dead remains sieved from the upper mixed-zone of the sedimentary column) and the local living community are typically attributed to natural postmortem processes. However, statistical analysis of 73 molluscan data sets from estuaries and lagoons reveals significantly poorer average “live-dead agreement” in settings of documented anthropogenic eutrophication (AE) than in areas where AE and other human impacts are negligible. Taxonomic similarity of paired live and dead species lists declines steadily among areas as a function of AE severity, and, for data sets comprising only adults, rank-order agreement in species abundance drops where AE is suspected. The observed live-dead differences in composition are consistent with eutrophication (anomalous abundance of seagrass-dwellers and/or scarcity of organic-loving species in the death assemblage), suggesting compositional inertia of death assemblages to recent environmental change. Molluscan data sets from open shelf settings (n = 34) also show higher average live-dead discordance in areas of AE. These results indicate that (i) live-dead discordance in surficial grab samples provides valuable evidence for strong anthropogenic modification of benthic communities, (ii) actualistic estimates of the ecological fidelity of molluscan death assemblages tend to be erroneously pessimistic when conducted in nonpristine settings, and (iii) based on their high fidelity in pristine study areas, death assemblages are a promising means of reconstructing otherwise elusive preimpact ecological baselines from sedimentary records. PMID:17965231

β-Decay Half-Lives of 110 Neutron-Rich Nuclei across the N=82 Shell Gap: Implications for the Mechanism and Universality of the Astrophysical r Process.

PubMed

Lorusso, G; Nishimura, S; Xu, Z Y; Jungclaus, A; Shimizu, Y; Simpson, G S; Söderström, P-A; Watanabe, H; Browne, F; Doornenbal, P; Gey, G; Jung, H S; Meyer, B; Sumikama, T; Taprogge, J; Vajta, Zs; Wu, J; Baba, H; Benzoni, G; Chae, K Y; Crespi, F C L; Fukuda, N; Gernhäuser, R; Inabe, N; Isobe, T; Kajino, T; Kameda, D; Kim, G D; Kim, Y-K; Kojouharov, I; Kondev, F G; Kubo, T; Kurz, N; Kwon, Y K; Lane, G J; Li, Z; Montaner-Pizá, A; Moschner, K; Naqvi, F; Niikura, M; Nishibata, H; Odahara, A; Orlandi, R; Patel, Z; Podolyák, Zs; Sakurai, H; Schaffner, H; Schury, P; Shibagaki, S; Steiger, K; Suzuki, H; Takeda, H; Wendt, A; Yagi, A; Yoshinaga, K

2015-05-15

The β-decay half-lives of 110 neutron-rich isotopes of the elements from _{37}Rb to _{50}Sn were measured at the Radioactive Isotope Beam Factory. The 40 new half-lives follow robust systematics and highlight the persistence of shell effects. The new data have direct implications for r-process calculations and reinforce the notion that the second (A≈130) and the rare-earth-element (A≈160) abundance peaks may result from the freeze-out of an (n,γ)⇄(γ,n) equilibrium. In such an equilibrium, the new half-lives are important factors determining the abundance of rare-earth elements, and allow for a more reliable discussion of the r process universality. It is anticipated that universality may not extend to the elements Sn, Sb, I, and Cs, making the detection of these elements in metal-poor stars of the utmost importance to determine the exact conditions of individual r-process events.

94 β -Decay Half-Lives of Neutron-Rich Cs 55 to Ho 67 : Experimental Feedback and Evaluation of the r -Process Rare-Earth Peak Formation

DOE PAGES

Wu, J.; Nishimura, S.; Lorusso, G.; ...

2017-02-16

The β-decay half-lives of 94 neutron-rich nuclei 144 $-$ 151Cs, 146 $-$ 154Ba, 148 $-$ 156La, 1 50 $-$ 158Ce, 153 $-$160Pr, 156 $-$ 162 Nd, 159 $-$ 163Pm, 160 $-$ 166Sm, 161 $-$ 168Eu , 165 $-$ 170Gd, 166 $-$ 172Tb, 169 $-$ 173Dy, 172 $-$ 175Ho, and two isomeric states 174 mEr, 172 mDy were measured at the Radioactive Isotope Beam Factory, providing a new experimental basis to test theoretical models. Strikingly large drops of β -decay half-lives are observed at neutron-number N = 97 for 58Ce, 59Pr, 60Nd , and 62Sm, and N = 105 for 63Eu,more » 64Gd, 65Tb, and 66Dy. Features in the data mirror the interplay between pairing effects and microscopic structure. In conclusion, $r$-process network calculations performed for a range of mass models and astrophysical conditions show that the 57 half-lives measured for the first time play an important role in shaping the abundance pattern of rare-earth elements in the solar system.« less

β-decay half-lives of new neutron-rich rare-earth isotopes 159Pm,162Sm, and 166Gd

NASA Astrophysics Data System (ADS)

Ichikawa, S.; Asai, M.; Tsukada, K.; Haba, H.; Nagame, Y.; Shibata, M.; Sakama, M.; Kojima, Y.

2005-06-01

The new neutron-rich rare-earth isotopes 159Pm, 162Sm, and 166Gd produced in the proton-induced fission of 238U were identified using the JAERI on-line isotope separator (JAERI-ISOL) coupled to a gas-jet transport system. The half-lives of 159Pm, 162Sm, and 166Gd were determined to be 1.5 ± 0.2, 2.4 ± 0.5, and 4.8 ± 1.0 s respectively. The partial decay scheme of 166Gd was constructed from γγ-coincidence data. A more accurate half-life value of 25.6 ± 2.2 s was obtained for the previously identified isotope 166Tb. The half-lives measured in the present study are in good agreement with the theoretical predictions calculated by the second generation of the gross theory with the atomic masses evaluated by Audi and Wapstra.

The hidden half: ecology and evolution of cryptobenthic fishes on coral reefs.

PubMed

Brandl, Simon J; Goatley, Christopher H R; Bellwood, David R; Tornabene, Luke

2018-05-07

Teleost fishes are the most diverse group of vertebrates on Earth. On tropical coral reefs, their species richness exceeds 6000 species; one tenth of total vertebrate biodiversity. A large proportion of this diversity is composed of cryptobenthic reef fishes (CRFs): bottom-dwelling, morphologically or behaviourally cryptic species typically less than 50 mm in length. Yet, despite their diversity and abundance, these fishes are both poorly defined and understood. Herein we provide a new quantitative definition and synthesise current knowledge on the diversity, distribution and life history of CRFs. First, we use size distributions within families to define 17 core CRF families as characterised by the high prevalence (>10%) of small-bodied species (<50 mm). This stands in strong contrast to 42 families of large reef fishes, in which virtually no small-bodied species have evolved. We posit that small body size has allowed CRFs to diversify at extremely high rates, primarily by allowing for fine partitioning of microhabitats and facilitation of allopatric reproductive isolation; yet, we are far from understanding and documenting the biodiversity of CRFs. Using rates of description since 1758, we predict that approximately 30 new species of cryptobenthic species will be described per year until 2050 (approximately twice the annual rate compared to large fishes). Furthermore, we predict that by the year 2031, more than half of the described coral reef fish biodiversity will consist of CRFs. These fishes are the 'hidden half' of vertebrate biodiversity on coral reefs. Notably, global geographic coverage and spatial resolution of quantitative data on CRF communities is uniformly poor, which further emphasises the remarkable reservoir of biodiversity that is yet to be discovered. Although small body size may have enabled extensive diversification within CRF families, small size also comes with a suite of ecological challenges that affect fishes' capacities to feed

94 β-Decay Half-Lives of Neutron-Rich _{55}Cs to _{67}Ho: Experimental Feedback and Evaluation of the r-Process Rare-Earth Peak Formation.

PubMed

Wu, J; Nishimura, S; Lorusso, G; Möller, P; Ideguchi, E; Regan, P-H; Simpson, G S; Söderström, P-A; Walker, P M; Watanabe, H; Xu, Z Y; Baba, H; Browne, F; Daido, R; Doornenbal, P; Fang, Y F; Gey, G; Isobe, T; Lee, P S; Liu, J J; Li, Z; Korkulu, Z; Patel, Z; Phong, V; Rice, S; Sakurai, H; Sinclair, L; Sumikama, T; Tanaka, M; Yagi, A; Ye, Y L; Yokoyama, R; Zhang, G X; Alharbi, T; Aoi, N; Bello Garrote, F L; Benzoni, G; Bruce, A M; Carroll, R J; Chae, K Y; Dombradi, Z; Estrade, A; Gottardo, A; Griffin, C J; Kanaoka, H; Kojouharov, I; Kondev, F G; Kubono, S; Kurz, N; Kuti, I; Lalkovski, S; Lane, G J; Lee, E J; Lokotko, T; Lotay, G; Moon, C-B; Nishibata, H; Nishizuka, I; Nita, C R; Odahara, A; Podolyák, Zs; Roberts, O J; Schaffner, H; Shand, C; Taprogge, J; Terashima, S; Vajta, Z; Yoshida, S

2017-02-17

The β-decay half-lives of 94 neutron-rich nuclei ^{144-151}Cs, ^{146-154}Ba, ^{148-156}La, ^{150-158}Ce, ^{153-160}Pr, ^{156-162}Nd, ^{159-163}Pm, ^{160-166}Sm, ^{161-168}Eu, ^{165-170}Gd, ^{166-172}Tb, ^{169-173}Dy, ^{172-175}Ho, and two isomeric states ^{174m}Er, ^{172m}Dy were measured at the Radioactive Isotope Beam Factory, providing a new experimental basis to test theoretical models. Strikingly large drops of β-decay half-lives are observed at neutron-number N=97 for _{58}Ce, _{59}Pr, _{60}Nd, and _{62}Sm, and N=105 for _{63}Eu, _{64}Gd, _{65}Tb, and _{66}Dy. Features in the data mirror the interplay between pairing effects and microscopic structure. r-process network calculations performed for a range of mass models and astrophysical conditions show that the 57 half-lives measured for the first time play an important role in shaping the abundance pattern of rare-earth elements in the solar system.

Half-lives of 221Fr, 217At, 213Bi, 213Po and 209Pb from the 225Ac decay series.

PubMed

Suliman, G; Pommé, S; Marouli, M; Van Ammel, R; Stroh, H; Jobbágy, V; Paepen, J; Dirican, A; Bruchertseifer, F; Apostolidis, C; Morgenstern, A

2013-07-01

The half-lives of (221)Fr, (217)At, (213)Bi, (213)Po, and (209)Pb were measured by means of an ion-implanted planar Si detector for alpha and beta particles emitted from weak (225)Ac sources or from recoil sources, which were placed in a quasi-2π counting geometry. Recoil sources were prepared by collecting atoms from an open (225)Ac source onto a glass substrate. The (221)Fr and (213)Bi half-lives were determined by following the alpha particle emission rate of recoil sources as a function of time. Similarly, the (209)Pb half-life was determined from the beta particle count rate. The shorter half-lives of (217)At and (213)Po were deduced from delayed coincidence measurements on weak (225)Ac sources using digital data acquisition in list mode. The resulting values: T1/2((221)Fr)=4.806 (6) min, T1/2((217)At)=32.8 (3)ms, T1/2((213)Bi)=45.62 (6)min, T1/2((213)Po)=3.708 (8) μs, and T1/2((209)Pb)=3.232 (5)h were in agreement only with the best literature data. Copyright © 2013 Elsevier Ltd. All rights reserved.

Application of simple mathematical expressions to relate the half-lives of xenobiotics in rats to values in humans.

PubMed

Ward, Keith W; Erhardt, Paul; Bachmann, Kenneth

2005-01-01

Previous publications from GlaxoSmithKline and University of Toledo laboratories convey our independent attempts to predict the half-lives of xenobiotics in humans using data obtained from rats. The present investigation was conducted to compare the performance of our published models against a common dataset obtained by merging the two sets of rat versus human half-life (hHL) data previously used by each laboratory. After combining data, mathematical analyses were undertaken by deploying both of our previous models, namely the use of an empirical algorithm based on a best-fit model and the use of rat-to-human liver blood flow ratios as a half-life correction factor. Both qualitative and quantitative analyses were performed, as well as evaluation of the impact of molecular properties on predictability. The merged dataset was remarkably diverse with respect to physiochemical and pharmacokinetic (PK) properties. Application of both models revealed similar predictability, depending upon the measure of stipulated accuracy. Certain molecular features, particularly rotatable bond count and pK(a), appeared to influence the accuracy of prediction. This collaborative effort has resulted in an improved understanding and appreciation of the value of rats to serve as a surrogate for the prediction of xenobiotic half-lives in humans when clinical pharmacokinetic studies are not possible or practicable.

Half-lives of 214Pb and 214Bi.

PubMed

Martz, D E; Langner, G H; Johnson, P R

1991-10-01

New measurements on chemically separated samples of 214Bi have yielded a mean half-life value of 19.71 +/- 0.02 min, where the error quoted is twice the standard deviation of the mean based on 23 decay runs. This result provides strong support for the historic 19.72 +/- 0.04 min half-life value and essentially excludes the 19.9-min value, both reported in previous studies. New measurements of the decay rate of 222Rn progeny activity initially in radioactive equilibrium have yielded a value of 26.89 +/- 0.03 min for the half-life of 214Pb, where the error quoted is twice the standard deviation of the mean based on 12 decay runs. This value is 0.1 min longer than the currently accepted 214Pb half-value of 26.8 min.

A tetraethylene glycol coat gives gold nanoparticles long in vivo half-lives with minimal increase in size

PubMed Central

Willett, Julian DS; Lawrence, Marlon G; Wilder, Jennifer C; Smithies, Oliver

2017-01-01

In this study, we describe the experiments determining whether coating gold nanoparticles with tetraethylene glycol (TEG) provides pharmacologically relevant advantages, such as increased serum half-life and resistance to protein adsorption. Monodisperse TEG-coated, NaBH4-reduced gold nanoparticles with a hydrodynamic size comparable to albumin were synthesized by reducing gold chloride with NaBH4 under alkaline conditions in the presence of TEG-SH. The particles were characterized by gel electrophoresis, column chromatography, and transmission electron microscopy. The nanoparticles were subsequently injected intravenously into mice, and their half-lives and final destinations were determined via photometric analysis, light microscopy (LM), and transmission electron microscopy. The TEG particles had a long half-life (~400 minutes) that was not influenced by splenectomy. After 500 minutes of injection, TEG particles were found in kidney proximal tubule cell vesicles and in spleen red and white pulp. The particles induced apoptosis in the spleen red pulp but not in white pulp or the kidney. Some of the TEG particles appeared to have undergone ligand exchange reactions that increased their charge. The TEG particles were shown to be resistant to nonspecific protein adsorption, as judged by gel electrophoresis and column chromatography. These results demonstrate that naturally monodisperse, small-sized gold nanoparticles coated with TEG have long in vivo plasma half-lives, are minimally toxic, and are resistant to protein adsorption. This suggests that a TEG coating should be considered as an alternative to a polyethylene glycol coating, which is polydisperse and of much larger size. PMID:28408825

Differences in the half-lives of some mitochondrial rat liver enzymes may derive partially from hepatocyte heterogeneity.

PubMed

Vargas, J L; Roche, E; Knecht, E; Grisolía, S

1987-11-16

The different turnover rates of rat liver mitochondrial enzymes make autophagy unlikely to be the main mechanism for degradation of mitochondria. Although alternatives have been presented, hepatocyte heterogeneity has not been considered. Lighter hepatocytes isolated in a discontinuous Percoll gradient contain more glutamate dehydrogenase (GDH) (half-life 1 day) and a more active autophagic system than heavier hepatocytes. The latter contain more carbamoyl phosphate synthase (CPS) and ornithine carbamoyl transferase (OTC) (half-lives 8 days) but less lysosomal activity. As expected, isolated autophagic vacuoles contain, relative to the mitochondrial content, 3-times less OTC and CPS than GDH, probably reflecting a faster lysosomal engulfment of mitochondria in the light hepatocytes (which contain more GDH). These data may explain some of the half-life differences of the enzymes studied.

School Effectiveness in Ecological Perspective.

ERIC Educational Resources Information Center

Bronfenbrenner, Urie; Hamilton, Stephen F.

This report focuses on the learning and development of primary and secondary school children, employing an "ecology of human development" model. This model is defined as involving the scientific study of the accommodation between growing human beings and the changing immediate settings in which they live and learn. The conceptual framework for the…

{beta}-decay half-lives of new neutron-rich rare-earth isotopes {sup 159}Pm,{sup 162}Sm, and {sup 166}Gd

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

Ichikawa, S.; Asai, M.; Tsukada, K.

The new neutron-rich rare-earth isotopes {sup 159}Pm, {sup 162}Sm, and {sup 166}Gd produced in the proton-induced fission of {sup 238}U were identified using the JAERI on-line isotope separator (JAERI-ISOL) coupled to a gas-jet transport system. The half-lives of {sup 159}Pm, {sup 162}Sm, and {sup 166}Gd were determined to be 1.5 {+-} 0.2, 2.4 {+-} 0.5, and 4.8 {+-} 1.0 s respectively. The partial decay scheme of {sup 166}Gd was constructed from {gamma}{gamma}-coincidence data. A more accurate half-life value of 25.6 {+-} 2.2 s was obtained for the previously identified isotope {sup 166}Tb. The half-lives measured in the present study aremore » in good agreement with the theoretical predictions calculated by the second generation of the gross theory with the atomic masses evaluated by Audi and Wapstra.« less

Ecology and social system of northern gibbons living in cold seasonal forests.

PubMed

Guan, Zhen-Hua; Ma, Chang-Yong; Fei, Han-Lan; Huang, Bei; Ning, Wen-He; Ni, Qing-Yong; Jiang, Xue-Long; Fan, Peng-Fei

2018-07-18

Gibbons in China represent the northernmost margin of present day gibbon species distribution (around N25°). Compared to tropical habitats, northern gibbon habitats are characterized by low temperatures and remarkable seasonal variation in fruit abundance. How gibbons adapt to their cold and seasonal habitats and what ecological factors affect their sociality are key questions for understanding their ecology and social system evolution, the elucidation of which will contribute to the conservation of these special populations/species. According to preliminary short-term studies, northern gibbons consume more leaves and use larger home ranges than tropical gibbons. Interestingly, some Nomascus groups consist of more than one adult female. However, these preliminary results are not well understood or incorporated into current socio-ecological theories regarding gibbon species. To better understand northern gibbons, our team has systematically studied three habituated groups of Nomascus concolor, three groups of N. nasutus, and two habituated groups of Hoolock tianxing since 2002. In this paper, we stress the challenges facing gibbons living in northern habitats and summarize their behavioral adaptations to their harsh environments. We also describe the northern gibbon social system and discuss the potential relationships between their ecology and sociality. Finally, we highlight future research questions related to northern gibbons in China.

The beauty of sensory ecology.

PubMed

Otálora-Luna, Fernando; Aldana, Elis

2017-08-10

Sensory ecology is a discipline that focuses on how living creatures use information to survive, but not to live. By trans-defining the orthodox concept of sensory ecology, a serious heterodox question arises: how do organisms use their senses to live, i.e. to enjoy or suffer life? To respond to such a query the objective (time-independent) and emotional (non-rational) meaning of symbols must be revealed. Our program is distinct from both the neo-Darwinian and the classical ecological perspective because it does not focus on survival values of phenotypes and their functions, but asks for the aesthetic effect of biological structures and their symbolism. Our message recognizes that sensing apart from having a survival value also has a beauty value. Thus, we offer a provoking and inspiring new view on the sensory relations of 'living things' and their surroundings, where the innovating power of feelings have more weight than the privative power of reason.

Influence of ethacrynic acid on glutathione S-transferase pi transcript and protein half-lives in human colon cancer cells.

PubMed

Shen, H; Ranganathan, S; Kuzmich, S; Tew, K D

1995-10-12

Ethacrynic acid (EA) is a plant phenolic acid that is both an inhibitor and an inducer of glutathione S-transferase (GST) activity. To determine contributory factors in the increased GST activity caused by EA treatment, human colon carcinoma HT29 cells were compared with a cloned EA-resistant population (HT6-8) maintained in medium containing 72 microM EA. Several factors are involved in the increased expression of GST pi in HT6-8. For example, nuclear run-on experiments showed an approximately 2-fold increase in the rate of transcription of GST pi. In addition, the half-life of GST pi transcript was increased from 4.1 (wild type, HT29, HT4-1) to 8.4 hr. The half-life of GST pi protein was 1-2 hr in HT4-1 cells versus 8-9 hr in HT6-8 cells. When either human ovarian carcinoma cells (SKOV3) or human prostatic carcinoma cells (DU145) were treated with EA, the half-life of the GST pi transcript was also increased. The transcript half-lives of another thiol-metabolism enzyme, gamma-glutamylcysteine synthetase (gamma-GCS), and a phase II detoxification enzyme, dihydrodiol dehydrogenase (DDH), were also increased in HT6-8, SKOV3 and DU145 cells treated with EA. However, the half-lives of transcripts from "housekeeping genes," such as glyceraldehyde 3-phosphate dehydrogenase (G3PDH), beta-actin and beta-tubulin, were not changed in these cell lines following EA. Apparently, a number of coordinated factors are involved in EA-enhanced expression of GST pi and other detoxification enzymes.

The detectability half-life in arthropod predator-prey research: what it is, why we need it, how to measure it, and how to use it.

PubMed

Greenstone, Matthew H; Payton, Mark E; Weber, Donald C; Simmons, Alvin M

2014-08-01

Molecular gut-content analysis enables detection of arthropod predation with minimal disruption of ecosystem processes. Most assays produce only qualitative results, with each predator testing either positive or negative for target prey remains. Nevertheless, they have yielded important insights into community processes. For example, they have confirmed the long-hypothesized role of generalist predators in retarding early-season build-up of pest populations prior to the arrival of more specialized predators and parasitoids and documented the ubiquity of secondary and intraguild predation. However, raw qualitative gut-content data cannot be used to assess the relative impact of different predator taxa on prey population dynamics: they must first be weighted by the relative detectability periods for molecular prey remains for each predator-prey combination. If this is not carried out, interpretations of predator impact will be biased towards those with the longest detectabilities. We review the challenges in determining detectability half-lives, including unstated assumptions that have often been ignored in the performance of feeding trials. We also show how detectability half-lives can be used to properly weight assay data to rank predators by their importance in prey population suppression, and how sets of half-lives can be used to test hypotheses concerning predator ecology and physiology. We use data from 32 publications, comprising 97 half-lives, to generate and test hypotheses on taxonomic differences in detectability half-lives and discuss the possible role of the detectability half-life in interpreting qPCR and next-generation sequencing data. © 2013 John Wiley & Sons Ltd.

Deformed shell model calculations of half lives for β+/EC decay and 2ν β+β+/β+EC/ECEC decay in medium-heavy N~Z nuclei

NASA Astrophysics Data System (ADS)

Mishra, S.; Shukla, A.; Sahu, R.; Kota, V. K. B.

2008-08-01

The β+/EC half-lives of medium heavy N~Z nuclei with mass number A~64-80 are calculated within the deformed shell model (DSM) based on Hartree-Fock states by employing a modified Kuo interaction in (2p3/2,1f5/2,2p1/2,1g9/2) space. The DSM model has been quite successful in predicting many spectroscopic properties of N~Z medium heavy nuclei with A~64-80. The calculated β+/EC half-lives, for prolate and oblate shapes, compare well with the predictions of the calculations with Skyrme force by Sarriguren Going further, following recent searches, half-lives for 2ν β+β+/β+EC/ECEC decay for the nucleus Kr78 are calculated using DSM and the results compare well with QRPA predictions.

Sexual objectification in women's daily lives: A smartphone ecological momentary assessment study.

PubMed

Holland, Elise; Koval, Peter; Stratemeyer, Michelle; Thomson, Fiona; Haslam, Nick

2017-06-01

Sexual objectification, particularly of young women, is highly prevalent in modern industrialized societies. Although there is plenty of experimental and cross-sectional research on objectification, prospective studies investigating the prevalence and psychological impact of objectifying events in daily life are scarce. We used ecological momentary assessment to track the occurrence of objectifying events over 1 week in the daily lives of young women (N = 81). Participants reported being targeted by a sexually objectifying event - most often the objectifying gaze - approximately once every 2 days and reported witnessing sexual objectification of others approximately 1.35 times per day. Further, multilevel linear regression analyses showed that being targeted by sexual objectification was associated with a substantial increase in state self-objectification. Overall, individual differences had little impact in moderating these effects. © 2016 The British Psychological Society.

Social Ecology, Deep Ecology and the Future of Green Political Thought.

ERIC Educational Resources Information Center

Tokar, Brian

1988-01-01

Describes the differences which divide the social ecology movement and the Deep Ecology Movement. Discusses how each views population ecology, politics, natural resources, and ecological living. Calls for a unified ecological movement. (CW)

β -decay half-lives and β -delayed neutron emission probabilities for several isotopes of Au, Hg, Tl, Pb, and Bi, beyond N =126

NASA Astrophysics Data System (ADS)

Caballero-Folch, R.; Domingo-Pardo, C.; Agramunt, J.; Algora, A.; Ameil, F.; Ayyad, Y.; Benlliure, J.; Bowry, M.; Calviño, F.; Cano-Ott, D.; Cortès, G.; Davinson, T.; Dillmann, I.; Estrade, A.; Evdokimov, A.; Faestermann, T.; Farinon, F.; Galaviz, D.; García, A. R.; Geissel, H.; Gelletly, W.; Gernhäuser, R.; Gómez-Hornillos, M. B.; Guerrero, C.; Heil, M.; Hinke, C.; Knöbel, R.; Kojouharov, I.; Kurcewicz, J.; Kurz, N.; Litvinov, Yu. A.; Maier, L.; Marganiec, J.; Marta, M.; Martínez, T.; Montes, F.; Mukha, I.; Napoli, D. R.; Nociforo, C.; Paradela, C.; Pietri, S.; Podolyák, Zs.; Prochazka, A.; Rice, S.; Riego, A.; Rubio, B.; Schaffner, H.; Scheidenberger, Ch.; Smith, K.; Sokol, E.; Steiger, K.; Sun, B.; Taín, J. L.; Takechi, M.; Testov, D.; Weick, H.; Wilson, E.; Winfield, J. S.; Wood, R.; Woods, P. J.; Yeremin, A.

2017-06-01

Background: There have been measurements on roughly 230 nuclei that are β -delayed neutron emitters. They range from 8He up to 150La. Apart from 210Tl, with a branching ratio of only 0.007%, no other neutron emitter has been measured beyond A =150 . Therefore, new data are needed, particularly in the region of heavy nuclei around N =126 , in order to guide theoretical models and help understand the formation of the third r -process peak at A ˜195 . Purpose: To measure both β -decay half-lives and neutron branching ratios of several neutron-rich Au, Hg, Tl, Pb, and Bi isotopes beyond N =126 . Method: Ions of interest were produced by fragmentation of a 238U beam, selected and identified via the GSI-FRS fragment separator. A stack of segmented silicon detectors (SIMBA) was used to measure ion implants and β decays. An array of 30 3He tubes embedded in a polyethylene matrix (BELEN) was used to detect neutrons with high efficiency and selectivity. A self-triggered digital system is employed to acquire data and to enable time correlations. The latter were analyzed with an analytical model and results for the half-lives and neutron-branching ratios were derived by using the binned maximum-likelihood method. Results: Twenty new β -decay half-lives are reported for Au-206204, Hg-211208,Tl-216211,Pb-218215 , and Bi-220218, nine of them for the first time. Neutron emission probabilities are reported for Hg,211210 and Tl-216211. Conclusions: The new β -decay half-lives are in good agreement with previous measurements on nuclei in this region. The measured neutron emission probabilities are comparable to or smaller than values predicted by global models such as relativistic Hartree Bogoliubov plus the relativistic quasi-particle random phase approximation (RHB + RQRPA).

HALO--a Java framework for precise transcript half-life determination.

PubMed

Friedel, Caroline C; Kaufmann, Stefanie; Dölken, Lars; Zimmer, Ralf

2010-05-01

Recent improvements in experimental technologies now allow measurements of de novo transcription and/or RNA decay at whole transcriptome level and determination of precise transcript half-lives. Such transcript half-lives provide important insights into the regulation of biological processes and the relative contributions of RNA decay and de novo transcription to differential gene expression. In this article, we present HALO (Half-life Organizer), the first software for the precise determination of transcript half-lives from measurements of RNA de novo transcription or decay determined with microarrays or RNA-seq. In addition, methods for quality control, filtering and normalization are supplied. HALO provides a graphical user interface, command-line tools and a well-documented Java application programming interface (API). Thus, it can be used both by biologists to determine transcript half-lives fast and reliably with the provided user interfaces as well as software developers integrating transcript half-life analysis into other gene expression profiling pipelines. Source code, executables and documentation are available at http://www.bio.ifi.lmu.de/software/halo.

Ecology as a Unifying Theme for Home Economics/Human Ecology.

ERIC Educational Resources Information Center

Vaines, Eleanore

1994-01-01

Discusses the complex character of everyday life as the deep ecology of Home Economics/Human Ecology. Explores the meanings of ecology and the ways in which diversity and harmony are interrelated companions of dynamic living systems. (JOW)

Half Lives for ``Irradiated'' Nonscience Majors

NASA Astrophysics Data System (ADS)

Geise, Kathleen; Hallam, Peter; Rattray, Rebecca; Stencel, Robert; Wolfe, Tristan

2014-03-01

We launched new hands-on radiation labs to supplement lecture material for undergraduate, non-science majors at the University of Denver to reinforce learning objectives during winter quarter 2014 and in order to help educate the public about nuclear energy decisions. Our learning objectives included: 1. differentiate between particle radiation and electro-magnetic radiation, 2. understand that particle radiation comes in alpha, beta and gamma types, 3. atomic and nuclear structure, 4. decay and half-life, 5. understand safe vs. unsafe doses and issues surrounding nuclear waste disposal. We used prelab surveys, prelab assessments, laboratory write-ups and quizzes to measure success with the learning objectives.

Half-lives of PFOS, PFHxS and PFOA after end of exposure to contaminated drinking water.

PubMed

Li, Ying; Fletcher, Tony; Mucs, Daniel; Scott, Kristin; Lindh, Christian H; Tallving, Pia; Jakobsson, Kristina

2018-01-01

Municipal drinking water contaminated with perfluorinated alkyl acids had been distributed to one-third of households in Ronneby, Sweden. The source was firefighting foam used in a nearby airfield since the mid-1980s. Clean water was provided from 16 December 2013. To determine the rates of decline in serum perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), and their corresponding half-lives. Up to seven blood samples were collected between June 2014 and September 2016 from 106 participants (age 4-84 years, 53% female). Median initial serum concentrations were PFHxS, 277 ng/mL (range 12-1660); PFOS, 345 ng/mL (range 24-1500); and PFOA, 18 ng/mL (range 2.4-92). The covariate-adjusted average rates of decrease in serum were PFHxS, 13% per year (95% CI 12% to 15%); PFOS, 20% per year (95% CI 19% to 22%); and PFOA, 26% per year (95% CI 24% to 28%). The observed data are consistent with a first-order elimination model. The mean estimated half-life was 5.3 years (95% CI 4.6 to 6.0) for PFHxS, 3.4 years (95% CI 3.1 to 3.7) for PFOS and 2.7 years (95% CI 2.5 to 2.9) for PFOA. The interindividual variation of half-life was around threefold when comparing the 5th and 95th percentiles. There was a marked sex difference with more rapid elimination in women for PFHxS and PFOS, but only marginally for PFOA. The estimated half-life for PFHxS was considerably longer than for PFOS and PFOA. For PFHxS and PFOS, the average half-life is shorter than the previously published estimates. For PFOA the half-life is in line with the range of published estimates. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Half-lives of PFOS, PFHxS and PFOA after end of exposure to contaminated drinking water

PubMed Central

Li, Ying; Fletcher, Tony; Mucs, Daniel; Scott, Kristin; Lindh, Christian H; Tallving, Pia; Jakobsson, Kristina

2018-01-01

Background Municipal drinking water contaminated with perfluorinated alkyl acids had been distributed to one-third of households in Ronneby, Sweden. The source was firefighting foam used in a nearby airfield since the mid-1980s. Clean water was provided from 16 December 2013. Objective To determine the rates of decline in serum perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), and their corresponding half-lives. Methods Up to seven blood samples were collected between June 2014 and September 2016 from 106 participants (age 4–84 years, 53% female). Results Median initial serum concentrations were PFHxS, 277 ng/mL (range 12–1660); PFOS, 345 ng/mL (range 24–1500); and PFOA, 18 ng/mL (range 2.4–92). The covariate-adjusted average rates of decrease in serum were PFHxS, 13% per year (95% CI 12% to 15%); PFOS, 20% per year (95% CI 19% to 22%); and PFOA, 26% per year (95% CI 24% to 28%). The observed data are consistent with a first-order elimination model. The mean estimated half-life was 5.3 years (95% CI 4.6 to 6.0) for PFHxS, 3.4 years (95% CI 3.1 to 3.7) for PFOS and 2.7 years (95% CI 2.5 to 2.9) for PFOA. The interindividual variation of half-life was around threefold when comparing the 5th and 95th percentiles. There was a marked sex difference with more rapid elimination in women for PFHxS and PFOS, but only marginally for PFOA. Conclusions The estimated half-life for PFHxS was considerably longer than for PFOS and PFOA. For PFHxS and PFOS, the average half-life is shorter than the previously published estimates. For PFOA the half-life is in line with the range of published estimates. PMID:29133598

Calculations of the β-decay half-lives of neutron-deficient nuclei

NASA Astrophysics Data System (ADS)

Tan, Wenjin; Ni, Dongdong; Ren, Zhongzhou

2017-05-01

In this work, β+/EC decays of some medium-mass nuclei are investigated within the extended quasiparticle random-phase approximation (QRPA), where neutron-neutron, proton-proton and neutron-proton (np) pairing correlations are taken into consideration in the specialized Hartree-Fock-Bogoliubov (HFB) transformation. In addition to the pairing interaction, the Brückner G-matrix obtained with the charge-dependent Bonn nucleon-nucleon force is used for the residual particle-particle and particle-hole interactions. Calculations are performed for even-even proton-rich isotopes ranging from Z=24 to Z=34. It is found that the np pairing interaction plays a significant role in β-decay for some nuclei far from stability. Compared with other theoretical calculations, our calculations show good agreement with the available experimental data. Predictions of β-decay half-lives for some very neutron-deficient nuclei are made for reference. Supported by National Nature Science Foundation of China (11535004, 11375086, 11120101005, 11175085 and 11235001), 973 Nation Major State Basic Research and Development of China (2013CB834400) and Science and Technology Development Fund of Macau (020/2014/A1 and 039/2013/A2)

β -decay half-lives and β -delayed neutron emission probabilities for several isotopes of Au, Hg, Tl, Pb, and Bi, beyond N = 126

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

Caballero-Folch, R.; Domingo-Pardo, C.; Agramunt, J.

Background: There have been measurements on roughly 230 nuclei that are β-delayed neutron emitters. They range from 8He up to 150La . Apart from 210Tl, with a branching ratio of only 0.007%, no other neutron emitter has been measured beyond A = 150 . Therefore, new data are needed, particularly in the region of heavy nuclei around N = 126 , in order to guide theoretical models and help understand the formation of the third r-process peak at A ~ 195. Purpose: To measure both β-decay half-lives and neutron branching ratios of several neutron-rich Au, Hg, Tl, Pb, and Bimore » isotopes beyond N = 126 . Method: Ions of interest were produced by fragmentation of a 238U beam, selected and identified via the GSI-FRS fragment separator. A stack of segmented silicon detectors (SIMBA) was used to measure ion implants and β decays. An array of 30 3He tubes embedded in a polyethylene matrix (BELEN) was used to detect neutrons with high efficiency and selectivity. A self-triggered digital system is employed to acquire data and to enable time correlations. The latter were analyzed with an analytical model and results for the half-lives and neutron-branching ratios were derived by using the binned maximum-likelihood method. Results: Twenty new β-decay half-lives are reported for 204-206Au, 208 – 211Hg, 211 – 216Tl , 215 – 218Pb, and 218 – 220Bi, nine of them for the first time. Neutron emission probabilities are reported for 210, 211Hg and 211 – 216Tl . Conclusions: The new β-decay half-lives are in good agreement with previous measurements on nuclei in this region. Lastly, the measured neutron emission probabilities are comparable to or smaller than values predicted by global models such as relativistic Hartree Bogoliubov plus the relativistic quasi-particle random phase approximation (RHB + RQRPA).« less

β -decay half-lives and β -delayed neutron emission probabilities for several isotopes of Au, Hg, Tl, Pb, and Bi, beyond N = 126

DOE PAGES

Caballero-Folch, R.; Domingo-Pardo, C.; Agramunt, J.; ...

2017-06-23

Background: There have been measurements on roughly 230 nuclei that are β-delayed neutron emitters. They range from 8He up to 150La . Apart from 210Tl, with a branching ratio of only 0.007%, no other neutron emitter has been measured beyond A = 150 . Therefore, new data are needed, particularly in the region of heavy nuclei around N = 126 , in order to guide theoretical models and help understand the formation of the third r-process peak at A ~ 195. Purpose: To measure both β-decay half-lives and neutron branching ratios of several neutron-rich Au, Hg, Tl, Pb, and Bimore » isotopes beyond N = 126 . Method: Ions of interest were produced by fragmentation of a 238U beam, selected and identified via the GSI-FRS fragment separator. A stack of segmented silicon detectors (SIMBA) was used to measure ion implants and β decays. An array of 30 3He tubes embedded in a polyethylene matrix (BELEN) was used to detect neutrons with high efficiency and selectivity. A self-triggered digital system is employed to acquire data and to enable time correlations. The latter were analyzed with an analytical model and results for the half-lives and neutron-branching ratios were derived by using the binned maximum-likelihood method. Results: Twenty new β-decay half-lives are reported for 204-206Au, 208 – 211Hg, 211 – 216Tl , 215 – 218Pb, and 218 – 220Bi, nine of them for the first time. Neutron emission probabilities are reported for 210, 211Hg and 211 – 216Tl . Conclusions: The new β-decay half-lives are in good agreement with previous measurements on nuclei in this region. Lastly, the measured neutron emission probabilities are comparable to or smaller than values predicted by global models such as relativistic Hartree Bogoliubov plus the relativistic quasi-particle random phase approximation (RHB + RQRPA).« less

Conflict or coordination? Assessing land use multi-functionalization using production-living-ecology analysis.

PubMed

Zhou, De; Xu, Jianchun; Lin, Zhulu

2017-01-15

Land use multi-functionalization (LUMF) promotes efficient and sustainable land use, reduces land pressures from limited land resources, and elevates urbanization quality in the midst of the increasingly tense relationship between humans and nature. In this study, we propose a new conceptual index system using system science, entropy weight method, triangle model, and coupling coordination degree model for LUMF assessment as well as an analysis of the relationship among land use sub-functions. This framework was applied to six cities in the urban agglomeration around Hangzhou Bay (UAHB) in eastern China's Zhejiang Province using twenty-two indicators in terms of production-living-ecology analysis during 2004-2013. The UAHB LUMF level increased over the past ten years, being affected by the designated functions and the "planning effect" for the six cities in the UAHB. The relationships among land use sub-functions in the six cities displayed strong variabilities at the spatial and temporal scales. The overall patterns of the relative importance of these sub-functions also differed from each other. Our research also shows that urban development in the UAHB had focused more on economic growth than on ecological protection and the regional development in the UAHB's six cities was unbalanced. Therefore, we suggest urban and land use management need to embrace more integrated planning and design in order to maintain efficient and sustainable land use. Copyright © 2016. Published by Elsevier B.V.

Preparation of desiccation-resistant aquatic-living Nostoc flagelliforme (Cyanophyceae) for potential ecological application

PubMed Central

Gao, Xiang; Yang, Yi-Wen; Cui, Li-Juan; Zhou, De-Bao; Qiu, Bao-Sheng

2015-01-01

Nostoc flagelliforme is a terrestrial edible cyanobacterium that grows in arid and semi-arid steppes. The continued over-exploitation in the last century has led to a sharp decline of this resource and a severe deterioration of the steppe ecology. Liquid-cultured N. flagelliforme serves as promising algal ‘seeds’ for resource restoration. In this study, macroscopic (or visible) aquatic-living colonies (MaACs) of N. flagelliforme were developed under weak light and high nitrogen conditions. In a 24 day shake-flask culture, MaACs were propagated by about 4.5-fold in biomass without loss of their macro-morphology; at the same time, the addition of weak UV-B treatment resulted in slightly bigger MaACs. Polyvinylpyrrolidone (PVP) k30, a water-soluble polymer, was used to generate the coating around MaACs, and after full desiccation, the coated MaACs could recover their photosynthetic physiological activity when rehydrated, with 4% PVP k30 for coating being most effective. In contrast, PVP k30-coated microscopic aquatic-living colonies of N. flagelliforme and non-coated MaACs showed no resistance to full desiccation. The macroscopic morphology or structure of MaACs should be crucial for the formation of protection by PVP k30 coating. PVP k30-coated MaACs were more approaching to actual application for resource restoration. PMID:25847617

Rayleigh wave effects in an elastic half-space.

NASA Technical Reports Server (NTRS)

Aggarwal, H. R.

1972-01-01

Consideration of Rayleigh wave effects in a homogeneous isotropic linearly elastic half-space subject to an impulsive uniform disk pressure loading. An approximate formula is obtained for the Rayleigh wave effects. It is shown that the Rayleigh waves near the center of loading arise from the portion of the dilatational and shear waves moving toward the axis, after they originate at the edge of the load disk. A study is made of the vertical displacement due to Rayleigh waves at points on the axis near the surface of the elastic half-space.

Search for long lived heaviest nuclei beyond the valley of stability

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

Chowdhury, P. Roy; Samanta, C.; Physics Department, Virginia Commonwealth University, Richmond, Virginia 23284-2000

2008-04-15

The existence of long lived superheavy nuclei (SHN) is controlled mainly by spontaneous fission and {alpha}-decay processes. According to microscopic nuclear theory, spherical shell effects at Z=114, 120, 126 and N=184 provide the extra stability to such SHN to have long enough lifetime to be observed. To investigate whether the so-called 'stability island' could really exist around the above Z, N values, the {alpha}-decay half-lives along with the spontaneous fission and {beta}-decay half-lives of such nuclei are studied. The {alpha}-decay half-lives of SHN with Z=102-120 are calculated in a quantum tunneling model with DDM3Y effective nuclear interaction using Q{sub {alpha}}more » values from three different mass formulas prescribed by Koura-Uno-Tachibana-Yamada (KUTY), Myers-Swiatecki (MS), and Muntian-Hofmann-Patyk-Sobiczewski (MMM). Calculation of spontaneous fission (SF) half-lives for the same SHN are carried out using a phenomenological formula and compared with SF half-lives predicted by Smolanczuk et al. A possible source of discrepancy between the calculated {alpha}-decay half-lives of some nuclei and the experimental data of GSI, JINR-FLNR, RIKEN, is discussed. In the region of Z=106-108 with N{approx}160-164, the {beta}-stable SHN {sub 106}{sup 268}Sg{sub 162} is predicted to have highest {alpha}-decay half-life (T{sub {alpha}}{approx}3.2 h) using Q{sub {alpha}} value from MMM. Interestingly, it is much greater than the recently measured T{sub {alpha}} ({approx}22 s) of deformed doubly magic {sub 108}{sup 270}Hs{sub 162} nucleus. A few fission-survived long-lived SHN which are either {beta}-stable or having large {beta}-decay half-lives are predicted to exist near {sup 294}110{sub 184}, {sup 293}110{sub 183}, {sup 296}112{sub 184}, and {sup 298}114{sub 184}. These nuclei might decay predominantly through {alpha}-particle emission.« less

Paws without claws? Ecological effects of large carnivores in anthropogenic landscapes

PubMed Central

Sahlén, E.; Elmhagen, B.; Chamaillé-Jammes, S.; Sand, H.; Lone, K.; Cromsigt, J. P. G. M.

2016-01-01

Large carnivores are frequently presented as saviours of biodiversity and ecosystem functioning through their creation of trophic cascades, an idea largely based on studies coming primarily out of relatively natural landscapes. However, in large parts of the world, particularly in Europe, large carnivores live in and are returning to strongly human-modified ecosystems. At present, we lack a coherent framework to predict the effects of large carnivores in these anthropogenic landscapes. We review how human actions influence the ecological roles of large carnivores by affecting their density or behaviour or those of mesopredators or prey species. We argue that the potential for density-mediated trophic cascades in anthropogenic landscapes is limited to unproductive areas where even low carnivore numbers may impact prey densities or to the limited parts of the landscape where carnivores are allowed to reach ecologically functional densities. The potential for behaviourally mediated trophic cascades may be larger and more widespread, because even low carnivore densities affect prey behaviour. We conclude that predator–prey interactions in anthropogenic landscapes will be highly context-dependent and human actions will often attenuate the ecological effects of large carnivores. We highlight the knowledge gaps and outline a new research avenue to study the role of carnivores in anthropogenic landscapes. PMID:27798302

A comparative analysis of alpha-decay half-lives for even-even 178Pb to 234U isotopes

NASA Astrophysics Data System (ADS)

Hosseini, S. S.; Hassanabadi, H.; Zarrinkamar, S.

2018-02-01

The feasibility for the alpha decay from the even-even transitions of 178Pb to 234U isotopes has been studied within the Coulomb and proximity potential model (CPPM). The alpha decay half-lives are considered from different theoretical approaches using Semi-empirical formula of Poenaru et al. (SemFIS), the Universal Decay law (UDL) of Qi et al., Akrawy-Dorin formula of Akrawy and Poenaru (ADF), the Scaling law of Brown (SLB) and the Scaling Law of Horoi et al. (SLH). The numerical results obtained by the CPPM and compared with other method as well the experimental data.

Indirect Effects of Global Change: From Physiological and Behavioral Mechanisms to Ecological Consequences.

PubMed

Gunderson, Alex R; Tsukimura, Brian; Stillman, Jonathon H

2017-07-01

A major focus of current ecological research is to understand how global change makes species vulnerable to extirpation. To date, mechanistic ecophysiological analyses of global change vulnerability have focused primarily on the direct effects of changing abiotic conditions on whole-organism physiological traits, such as metabolic rate, locomotor performance, cardiac function, and critical thermal limits. However, species do not live in isolation within their physical environments, and direct effects of climate change are likely to be compounded by indirect effects that result from altered interactions with other species, such as competitors and predators. The Society for Integrative and Comparative Biology 2017 Symposium "Indirect Effects of Global Change: From Physiological and Behavioral Mechanisms to Ecological Consequences" was designed to synthesize multiple approaches to investigating the indirect effects of global change by bringing together researchers that study the indirect effects of global change from multiple perspectives across habitat, type of anthropogenic change, and level of biological organization. Our goal in bringing together researchers from different backgrounds was to foster cross-disciplinary insights into the mechanistic bases and higher-order ecological consequences of indirect effects of global change, and to promote collaboration among fields. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Neutron activation analyses and half-life measurements at the usgs triga reactor

NASA Astrophysics Data System (ADS)

Larson, Robert E.

Neutron activation of materials followed by gamma spectroscopy using high-purity germanium detectors is an effective method for making measurements of nuclear beta decay half-lives and for detecting trace amounts of elements present in materials. This research explores applications of neutron activation analysis (NAA) in two parts. Part 1. High Precision Methods for Measuring Decay Half-Lives, Chapters 1 through 8 Part one develops research methods and data analysis techniques for making high precision measurements of nuclear beta decay half-lives. The change in the electron capture half-life of 51Cr in pure chromium versus chromium mixed in a gold lattice structure is explored, and the 97Ru electron capture decay half-life are compared for ruthenium in a pure crystal versus ruthenium in a rutile oxide state, RuO2. In addition, the beta-minus decay half-life of 71mZn is measured and compared with new high precision findings. Density Functional Theory is used to explain the measured magnitude of changes in electron capture half-life from changes in the surrounding lattice electron configuration. Part 2. Debris Collection Nuclear Diagnostic at the National Ignition Facility, Chapters 9 through 11 Part two explores the design and development of a solid debris collector for use as a diagnostic tool at the National Ignition Facility (NIF). NAA measurements are performed on NIF post-shot debris collected on witness plates in the NIF chamber. In this application NAA is used to detect and quantify the amount of trace amounts of gold from the hohlraum and germanium from the pellet present in the debris collected after a NIF shot. The design of a solid debris collector based on material x-ray ablation properties is given, and calculations are done to predict performance and results for the collection and measurements of trace amounts of gold and germanium from dissociated hohlraum debris.

Preparation of desiccation-resistant aquatic-living Nostoc flagelliforme (Cyanophyceae) for potential ecological application.

PubMed

Gao, Xiang; Yang, Yi-Wen; Cui, Li-Juan; Zhou, De-Bao; Qiu, Bao-Sheng

2015-11-01

Nostoc flagelliforme is a terrestrial edible cyanobacterium that grows in arid and semi-arid steppes. The continued over-exploitation in the last century has led to a sharp decline of this resource and a severe deterioration of the steppe ecology. Liquid-cultured N. flagelliforme serves as promising algal 'seeds' for resource restoration. In this study, macroscopic (or visible) aquatic-living colonies (MaACs) of N. flagelliforme were developed under weak light and high nitrogen conditions. In a 24 day shake-flask culture, MaACs were propagated by about 4.5-fold in biomass without loss of their macro-morphology; at the same time, the addition of weak UV-B treatment resulted in slightly bigger MaACs. Polyvinylpyrrolidone (PVP) k30, a water-soluble polymer, was used to generate the coating around MaACs, and after full desiccation, the coated MaACs could recover their photosynthetic physiological activity when rehydrated, with 4% PVP k30 for coating being most effective. In contrast, PVP k30-coated microscopic aquatic-living colonies of N. flagelliforme and non-coated MaACs showed no resistance to full desiccation. The macroscopic morphology or structure of MaACs should be crucial for the formation of protection by PVP k30 coating. PVP k30-coated MaACs were more approaching to actual application for resource restoration. © 2015 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

The Use of Gene Ontology Term and KEGG Pathway Enrichment for Analysis of Drug Half-Life

PubMed Central

Chen, Lei; Lu, Jing; Kong, XiangYin; Huang, Tao; Li, HaiPeng

2016-01-01

A drug’s biological half-life is defined as the time required for the human body to metabolize or eliminate 50% of the initial drug dosage. Correctly measuring the half-life of a given drug is helpful for the safe and accurate usage of the drug. In this study, we investigated which gene ontology (GO) terms and biological pathways were highly related to the determination of drug half-life. The investigated drugs, with known half-lives, were analyzed based on their enrichment scores for associated GO terms and KEGG pathways. These scores indicate which GO terms or KEGG pathways the drug targets. The feature selection method, minimum redundancy maximum relevance, was used to analyze these GO terms and KEGG pathways and to identify important GO terms and pathways, such as sodium-independent organic anion transmembrane transporter activity (GO:0015347), monoamine transmembrane transporter activity (GO:0008504), negative regulation of synaptic transmission (GO:0050805), neuroactive ligand-receptor interaction (hsa04080), serotonergic synapse (hsa04726), and linoleic acid metabolism (hsa00591), among others. This analysis confirmed our results and may show evidence for a new method in studying drug half-lives and building effective computational methods for the prediction of drug half-lives. PMID:27780226

Estimation of elimination half-lives of organic chemicals in humans using gradient boosting machine.

PubMed

Lu, Jing; Lu, Dong; Zhang, Xiaochen; Bi, Yi; Cheng, Keguang; Zheng, Mingyue; Luo, Xiaomin

2016-11-01

Elimination half-life is an important pharmacokinetic parameter that determines exposure duration to approach steady state of drugs and regulates drug administration. The experimental evaluation of half-life is time-consuming and costly. Thus, it is attractive to build an accurate prediction model for half-life. In this study, several machine learning methods, including gradient boosting machine (GBM), support vector regressions (RBF-SVR and Linear-SVR), local lazy regression (LLR), SA, SR, and GP, were employed to build high-quality prediction models. Two strategies of building consensus models were explored to improve the accuracy of prediction. Moreover, the applicability domains (ADs) of the models were determined by using the distance-based threshold. Among seven individual models, GBM showed the best performance (R(2)=0.820 and RMSE=0.555 for the test set), and Linear-SVR produced the inferior prediction accuracy (R(2)=0.738 and RMSE=0.672). The use of distance-based ADs effectively determined the scope of QSAR models. However, the consensus models by combing the individual models could not improve the prediction performance. Some essential descriptors relevant to half-life were identified and analyzed. An accurate prediction model for elimination half-life was built by GBM, which was superior to the reference model (R(2)=0.723 and RMSE=0.698). Encouraged by the promising results, we expect that the GBM model for elimination half-life would have potential applications for the early pharmacokinetic evaluations, and provide guidance for designing drug candidates with favorable in vivo exposure profile. This article is part of a Special Issue entitled "System Genetics" Guest Editor: Dr. Yudong Cai and Dr. Tao Huang. Copyright © 2016 Elsevier B.V. All rights reserved.

Half-life of Xe120

NASA Astrophysics Data System (ADS)

Phillips, A. A.; Andreoiu, C.; Ball, G. C.; Bandyopadhyay, D.; Behr, J. A.; Chupp, T. E.; Finlay, P.; Garrett, P. E.; Grinyer, G. F.; Hackman, G.; Hayden, M. E.; Hyland, B.; Nuss-Warren, S. R.; Pearson, M. R.; Schumaker, M. A.; Smith, M. B.; Svensson, C. E.; Tardiff, E. R.; Valiente-Dobón, J. J.; Warner, T.

2006-08-01

We have measured the half-life of Xe120 using a high-purity germanium (HPGe) detector to monitor the 176, 178, and 762 keV γ rays from Xe120 β+ decay. The result, 46±0.6 min, differs significantly from the value 40±1 min reported by Andersson [Ark. Fys. 28, 37 (1964)]. We have also measured the half-lives of Cs120 and I120 to be 60±0.7 s and 82.1±0.6 min, respectively, both of which are consistent with previous measurements.

Effective discharge analysis of ecological processes in streams

USGS Publications Warehouse

Doyle, Martin W.; Stanley, Emily H.; Strayer, David L.; Jacobson, Robert B.; Schmidt, John C.

2005-01-01

Discharge is a master variable that controls many processes in stream ecosystems. However, there is uncertainty of which discharges are most important for driving particular ecological processes and thus how flow regime may influence entire stream ecosystems. Here the analytical method of effective discharge from fluvial geomorphology is used to analyze the interaction between frequency and magnitude of discharge events that drive organic matter transport, algal growth, nutrient retention, macroinvertebrate disturbance, and habitat availability. We quantify the ecological effective discharge using a synthesis of previously published studies and modeling from a range of study sites. An analytical expression is then developed for a particular case of ecological effective discharge and is used to explore how effective discharge varies within variable hydrologic regimes. Our results suggest that a range of discharges is important for different ecological processes in an individual stream. Discharges are not equally important; instead, effective discharge values exist that correspond to near modal flows and moderate floods for the variable sets examined. We suggest four types of ecological response to discharge variability: discharge as a transport mechanism, regulator of habitat, process modulator, and disturbance. Effective discharge analysis will perform well when there is a unique, essentially instantaneous relationship between discharge and an ecological process and poorly when effects of discharge are delayed or confounded by legacy effects. Despite some limitations the conceptual and analytical utility of the effective discharge analysis allows exploring general questions about how hydrologic variability influences various ecological processes in streams.

Half-life Measurements of Excited Levels in Fission Products around Mass Number 150

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

Kojima, Y., E-mail: kojima.yasuaki@f.mbox.nagoya-u.ac.jp; Shima, Y.; Hayashi, H.

2014-06-15

A spectrometer to measure nuclear level half-lives has been installed at the on-line isotope separator of the Kyoto University Reactor. This spectrometer consists of a LaBr3 scintillator, a thin plastic scintillator and an HPGe detector. Half-lives are deduced using the β-γ-γ delayed coincidence method. The prompt-time distribution curves measured with the spectrometer give a time resolution (FWHM) of 600 ps for 100-keV γ rays. This resolution means that half-lives down to the subnanosecond range or shorter can be measured. We reported recent measurements of the half-life of {sup 149}Pr and {sup 149}Nd. Some of the more interesting results include themore » first determination of the half-lives of {sup 149}Pr levels at 86.5 and 125.6 keV, which are 4.2(5) ns and 1.0(2) ns, respectively. In addition, the data indicate that the half-life of the 270.8-keV level in {sup 149}Nd is not 5.1(3) ns as reported previously, but 0.42(3) ns.« less

Nonmicrowave health and ecological effects: Overview

NASA Technical Reports Server (NTRS)

White, M. R.

1980-01-01

The potential environmental impacts due to the operation and construction of the Satellite Power System are discussed. The nonmicrowave health and ecological effects encompass impacts on the public, the terrestrial worker, the space worker, the ecology, and agriculture.

First Compilation and Evaluation of Beta-Delayed Neutron Emission Probabilities and Associated Half-Lives for A ≤72 Nuclei

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

Birch, M.; Singh, B.; Abriola, D.

2014-06-01

After a comprehensive compilation and evaluation of beta-delayed neutron (β -n) emission probabilities, P n, and associated half-lives for A ≤ 72 nuclei has been performed for the first time. The recommended values have been used to analyze the systematics of β -nemission in this region. The ratio P n/T 1/2 is better correlated with the Q-value of the β -n decay mode than the previously proposed Kratz-Herrmann Formula (KHF). Moreover, the recommended values are also compared with theoretical quasi-particle random phase approximation (QRPA) calculations.

Ecological Inventory Exemplars.

ERIC Educational Resources Information Center

Sobsey, Dick, Ed.

The document contains 20 ecological inventories (developed at the University of Minnesota and the University of Alberta) to help severely disabled students learn functional living skills. The ecological approach is designed to uncover the functions critical for success in specific environments which the student frequently encounters. Matching the…

Levels of organization in biology: on the nature and nomenclature of ecology's fourth level.

PubMed

Lidicker, William Z

2008-02-01

Viewing the universe as being composed of hierarchically arranged systems is widely accepted as a useful model of reality. In ecology, three levels of organization are generally recognized: organisms, populations, and communities (biocoenoses). For half a century increasing numbers of ecologists have concluded that recognition of a fourth level would facilitate increased understanding of ecological phenomena. Sometimes the word "ecosystem" is used for this level, but this is arguably inappropriate. Since 1986, I and others have argued that the term "landscape" would be a suitable term for a level of organization defined as an ecological system containing more than one community type. However, "landscape" and "landscape level" continue to be used extensively by ecologists in the popular sense of a large expanse of space. I therefore now propose that the term "ecoscape" be used instead for this fourth level of organization. A clearly defined fourth level for ecology would focus attention on the emergent properties of this level, and maintain the spatial and temporal scale-free nature inherent in this hierarchy of organizational levels for living entities.

Prehension of Half-Full and Half-Empty Glasses: Time and History Effects on Multi-Digit Coordination

PubMed Central

Sun, Yao; Zatsiorsky, Vladimir M.; Latash, Mark L.

2011-01-01

We explored how digit forces and indices of digit coordination depend on the history of getting to a particular set of task parameters during static prehension tasks. The participants held in the right hand an instrumented handle with a light-weight container attached on top of the handle. At the beginning of each trial, the container could be empty, filled to the half with water (0.4 l) or filled to the top (0.8 l). The water was pumped in/out of the container at a constant, slow rate over 10 s. At the end of each trial, the participants always held a half-filled container that has just been filled (Empty-Half), emptied (Full-Half), or stayed half-filled throughout the trial (Half-Only). Indices of co-variation (synergy indices) of elemental variables (forces and moments of force produced by individual digits) stabilizing such performance variables as total normal force, total tangetial force, and total moment of force were computed at two levels of an assumed control hierarchy. At the upper level, the task is shared between the thumb and virtual finger (an imagined digit with the mechanical action equal to that of the four fingers), while at the lower level, action of the virtual finger is shared among the actual four fingers. Filling or emptying the container led to a drop in the safety margin (proportion of grip force over the slipping threshold) below the values observed in the Half-Only condition. Synergy indices at both levels of the hierarchy showed changes over the Full-Half and Empty-Half condition. These changes could be monotonic (typical of moment of force and normal force) or non-monotonic (typical of tangential force). For both normal and tangential forces, higher synergy indices at the higher level of the hierarchy corresponded to lower indices at the lower level. Significant differences in synergy indices across conditions were seen at the final steady-state showing that digit coordination during steady holding an object is history dependent. The

Tests of a Fast Plastic Scintillator for High-Precision Half-Life Measurements

NASA Astrophysics Data System (ADS)

Laffoley, A. T.; Dunlop, R.; Finlay, P.; Leach, K. G.; Michetti-Wilson, J.; Rand, E. T.; Svensson, C. E.; Grinyer, G. F.; Thomas, J. C.; Ball, G.; Garnsworthy, A. B.; Hackman, G.; Orce, J. N.; Triambak, S.; Williams, S. J.; Andreoiu, C.; Cross, D.

2013-03-01

A fast plastic scintillator detector is evaluated for possible use in an ongoing program of high-precision half-life measurements of short lived β emitters. Using data taken at TRI-UMF's Isotope Separator and Accelerator Facility with a radioactive 26Na beam, a detailed investigation of potential systematic effects with this new detector setup is being performed. The technique will then be applied to other β-decay half-life measurements including the superallowed Fermi β emitters 10C, 14O, and T = 1/2 decay of 15O.

Changes in ambient dose equivalent rates around roads at Kawamata town after the Fukushima accident.

PubMed

Kinase, Sakae; Sato, Satoshi; Sakamoto, Ryuichi; Yamamoto, Hideaki; Saito, Kimiaki

2015-11-01

Changes in ambient dose equivalent rates noted through vehicle-borne surveys have elucidated ecological half-lives of radioactive caesium in the environment. To confirm that the ecological half-lives are appropriate for predicting ambient dose equivalent rates within living areas, it is important to ascertain ambient dose equivalent rates on/around roads. In this study, radiation monitoring on/around roads at Kawamata town, located about 37 km northwest of the Fukushima Daiichi Nuclear Power Plant, was performed using monitoring vehicles and survey meters. It was found that the ambient dose equivalent rates around roads were higher than those on roads as of October 2012. And withal the ecological half-lives on roads were essentially consistent with those around roads. With dose predictions using ecological half-lives on roads, it is necessary to make corrections to ambient dose equivalent rates through the vehicle-borne surveys against those within living areas. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A common scaling rule for abundance, energetics, and production of parasitic and free-living species

USGS Publications Warehouse

Hechinger, Ryan F.; Lafferty, Kevin D.; Dobson, Andy P.; Brown, James H.; Kuris, Armand M.

2011-01-01

The metabolic theory of ecology uses the scaling of metabolism with body size and temperature to explain the causes and consequences of species abundance. However, the theory and its empirical tests have never simultaneously examined parasites alongside free-living species. This is unfortunate because parasites represent at least half of species diversity. We show that metabolic scaling theory could not account for the abundance of parasitic or free-living species in three estuarine food webs until accounting for trophic dynamics. Analyses then revealed that the abundance of all species uniformly scaled with body mass to the - 3/4 power. This result indicates "production equivalence," where biomass production within trophic levels is invariant of body size across all species and functional groups: invertebrate or vertebrate, ectothermic or endothermic, and free-living or parasitic.

Genetic Allee effects and their interaction with ecological Allee effects.

PubMed

Wittmann, Meike J; Stuis, Hanna; Metzler, Dirk

2018-01-01

It is now widely accepted that genetic processes such as inbreeding depression and loss of genetic variation can increase the extinction risk of small populations. However, it is generally unclear whether extinction risk from genetic causes gradually increases with decreasing population size or whether there is a sharp transition around a specific threshold population size. In the ecological literature, such threshold phenomena are called 'strong Allee effects' and they can arise for example from mate limitation in small populations. In this study, we aim to (i) develop a meaningful notion of a 'strong genetic Allee effect', (ii) explore whether and under what conditions such an effect can arise from inbreeding depression due to recessive deleterious mutations, and (iii) quantify the interaction of potential genetic Allee effects with the well-known mate-finding Allee effect. We define a strong genetic Allee effect as a genetic process that causes a population's survival probability to be a sigmoid function of its initial size. The inflection point of this function defines the critical population size. To characterize survival-probability curves, we develop and analyse simple stochastic models for the ecology and genetics of small populations. Our results indicate that inbreeding depression can indeed cause a strong genetic Allee effect, but only if individuals carry sufficiently many deleterious mutations (lethal equivalents). Populations suffering from a genetic Allee effect often first grow, then decline as inbreeding depression sets in and then potentially recover as deleterious mutations are purged. Critical population sizes of ecological and genetic Allee effects appear to be often additive, but even superadditive interactions are possible. Many published estimates for the number of lethal equivalents in birds and mammals fall in the parameter range where strong genetic Allee effects are expected. Unfortunately, extinction risk due to genetic Allee effects

Metabolic biotransformation half-lives in fish: QSAR modeling and consensus analysis.

PubMed

Papa, Ester; van der Wal, Leon; Arnot, Jon A; Gramatica, Paola

2014-02-01

Bioaccumulation in fish is a function of competing rates of chemical uptake and elimination. For hydrophobic organic chemicals bioconcentration, bioaccumulation and biomagnification potential are high and the biotransformation rate constant is a key parameter. Few measured biotransformation rate constant data are available compared to the number of chemicals that are being evaluated for bioaccumulation hazard and for exposure and risk assessment. Three new Quantitative Structure-Activity Relationships (QSARs) for predicting whole body biotransformation half-lives (HLN) in fish were developed and validated using theoretical molecular descriptors that seek to capture structural characteristics of the whole molecule and three data set splitting schemes. The new QSARs were developed using a minimal number of theoretical descriptors (n=9) and compared to existing QSARs developed using fragment contribution methods that include up to 59 descriptors. The predictive statistics of the models are similar thus further corroborating the predictive performance of the different QSARs; Q(2)ext ranges from 0.75 to 0.77, CCCext ranges from 0.86 to 0.87, RMSE in prediction ranges from 0.56 to 0.58. The new QSARs provide additional mechanistic insights into the biotransformation capacity of organic chemicals in fish by including whole molecule descriptors and they also include information on the domain of applicability for the chemical of interest. Advantages of consensus modeling for improving overall prediction and minimizing false negative errors in chemical screening assessments, for identifying potential sources of residual error in the empirical HLN database, and for identifying structural features that are not well represented in the HLN dataset to prioritize future testing needs are illustrated. © 2013.

Restoring fish ecological quality in estuaries: Implication of interactive and cumulative effects among anthropogenic stressors.

PubMed

Teichert, Nils; Borja, Angel; Chust, Guillem; Uriarte, Ainhize; Lepage, Mario

2016-01-15

Estuaries are subjected to multiple anthropogenic stressors, which have additive, antagonistic or synergistic effects. Current challenges include the use of large databases of biological monitoring surveys (e.g. the European Water Framework Directive) to help environmental managers prioritizing restoration measures. This study investigated the impact of nine stressor categories on the fish ecological status derived from 90 estuaries of the North East Atlantic countries. We used a random forest model to: 1) detect the dominant stressors and their non-linear effects; 2) evaluate the ecological benefits expected from reducing pressure from stressors; and 3) investigate the interactions among stressors. Results showed that largest restoration benefits were expected when mitigating water pollution and oxygen depletion. Non-additive effects represented half of pairwise interactions among stressors, and antagonisms were the most common. Dredged sediments, flow changes and oxygen depletion were predominantly implicated in non-additive interactions, whereas the remainder stressors often showed additive impacts. The prevalence of interactive impacts reflects a complex scenario for estuaries management; hence, we proposed a step-by-step restoration scheme focusing on the mitigation of stressors providing the maximum of restoration benefits under a multi-stress context. Copyright © 2015 Elsevier B.V. All rights reserved.

Industrial ecology: reflections on a colloquium.

PubMed Central

Ausubel, J H

1992-01-01

Industrial ecology is the network of all industrial processes as they may interact with each other and live off each other, not only in the economic sense, but also in the sense of direct use of each other's material and energy wastes and products. This paper, which reflects upon the papers and discussions at the National Academy of Sciences Colloquium on Industrial Ecology on May 20-21, 1991, is structured around 10 questions. Do sociotechnical systems have long-range environmental goals? How is the concept of industrial ecology useful and timely? What are environmental technologies? Is there a systematic way to choose among alternatives for improving the ecology of technologies? What are ways to measure performance with respect to industrial ecology? What are the sources and rates of innovation in environmental technologies? How is the market economy performing with respect to industrial ecology? What will be the effect of the ecological modernization of the developed nations of the North on the developing countries of the South? How can creative interaction on environmental issues be fostered among diverse social groups? How must research and education change? PMID:11607273

Long-term lunar stations: Some ecological considerations

NASA Technical Reports Server (NTRS)

Maguire, Bassett, Jr.; Scott, Kelly W.

1992-01-01

A major factor for long-term success of a lunar station is the ability to keep an agroecosystem functioning at a desirable, stable steady-state with ecological stability and reliability. Design for a long-lived extraterrestrial manned station must take into account interactions among its subsystems to insure that overall functionality is enhanced (or at least not compromised). Physical isolation of feed production, human living areas, recycling, and other systems may be straightforward, however, microbiological isolation will be very difficult. While it is possible to eliminate plant-associated microbiological communities by growing the plants asepticallly, it is not practical to keep plants germ-free on a large scale if humans are working with them. Ecological theory strongly suggests that some kinds of communities or organisms effectively increase the stability of ecosystems and will protect the plants from potential pathogens. A carefully designed and maintained (lunar-derived) soil can provide a variety of habitats for effective microbial buffers while adding structure to the agroecosystem. A soil can also increase ecosystem reliability through buffering otherwise large element and compound fluctuations (of nutrients, wastes, etc.) as well as buffering temperature level and atmosphere composition. We are doing experiments in ecological dynamics and attempting to extend the relevant theories.

Aspen's ecological role in the West

Treesearch

William H. Romme; Lisa Floyd-Hanna; David D. Hanna; Elisabeth Bartlett

2001-01-01

Aspen exhibits a variety of ecological roles. In southern Colorado, the 1880 landscape mosaic contained a range of stand ages, of which half were >70 years old and half were younger. Pure aspen stands in southern Colorado are widespread and may result from previous short fire intervals that eliminated local conifer seed sources. Aspen regeneration in northern...

The analysis of predictability of recent alpha decay formulae and the alpha partial half-lives of some exotic nuclei

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

Dasgupta-Schubert, N.; Reyes, M. A.; Tamez, V. A.

2009-04-20

Alpha decay is one of the two main decay modes of the heaviest nuclei, (SHE), and constitutes one of the dominant decay modes of highly neutron deficient medium mass nuclei ('exotics'). Thus identifying and characterizing the alpha decay chains form a crucial part of the identification of SHE. We report the extension of the previously developed method for the detailed and systematic investigation of the reliability of the three main extant analytical formulae of alpha decay half-lives: the generalized liquid drop model based formula of Royer et al. (FR), the Sobiczewski modified semi-empirical Viola-Seaborg formula (VSS) and the recent phenomenologicalmore » formula of Sobiczewski and Parkhomenko (SP)« less

Challenges, developments and perspectives in intermittent river ecology

EPA Science Inventory

Although more than half the world's river networks comprise channels that periodically cease to flow and dry [intermittent rivers (IRs)], river ecology was largely developed from and for perennial systems. Ecological knowledge of IRs is rapidly increasing, so there is a need to s...

Ecological and Evolutionary Effects of Stickleback on Community Structure

PubMed Central

Des Roches, Simone; Shurin, Jonathan B.; Schluter, Dolph; Harmon, Luke J.

2013-01-01

Species’ ecology and evolution can have strong effects on communities. Both may change concurrently when species colonize a new ecosystem. We know little, however, about the combined effects of ecological and evolutionary change on community structure. We simultaneously examined the effects of top-predator ecology and evolution on freshwater community parameters using recently evolved generalist and specialist ecotypes of three-spine stickleback (Gasterosteus aculeatus). We used a mesocosm experiment to directly examine the effects of ecological (fish presence and density) and evolutionary (phenotypic diversity and specialization) factors on community structure at lower trophic levels. We evaluated zooplankton biomass and composition, periphyton and phytoplankton chlorophyll-a concentration, and net primary production among treatments containing different densities and diversities of stickleback. Our results showed that both ecological and evolutionary differences in the top-predator affect different aspects of community structure and composition. Community structure, specifically the abundance of organisms at each trophic level, was affected by stickleback presence and density, whereas composition of zooplankton was influenced by stickleback diversity and specialization. Primary productivity, in terms of chlorophyll-a concentration and net primary production was affected by ecological but not evolutionary factors. Our results stress the importance of concurrently evaluating both changes in density and phenotypic diversity on the structure and composition of communities. PMID:23573203

Average and recommended half-life values for two neutrino double beta decay: Upgrade-2013

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

Barabash, A. S.

2013-12-30

All existing positive results on two neutrino double beta decay in different nuclei were analyzed. Using the procedure recommended by the Particle Data Group, weighted average values for half-lives of {sup 48}Ca, {sup 76}Ge, {sup 82}Se, {sup 96}Zr, {sup 100}Mo, {sup 100}Mo−{sup 100}Ru (0{sub 1}{sup +}), {sup 116}Cd, {sup 130}Te, {sup 136}Xe, {sup 150}Nd, {sup 150}Nd−{sup 150}Sm (0{sub 1}{sup +}) and {sup 238}U were obtained. Existing geochemical data were analyzed and recommended values for half-lives of {sup 128}Te and {sup 130}Ba are proposed. I recommend the use of these results as the most currently reliable values for half-lives.

Combining Optical Reporter Proteins with Different Half-lives to Detect Temporal Evolution of Hypoxia and Reoxygenation in Tumors

PubMed Central

Danhier, Pierre; Krishnamachary, Balaji; Bharti, Santosh; Kakkad, Samata; Mironchik, Yelena; Bhujwalla, Zaver M.

2015-01-01

Here we have developed a hypoxia response element driven imaging strategy that combined the hypoxia-driven expression of two optical reporters with different half-lives to detect temporal changes in hypoxia and hypoxia inducible factor (HIF) activity. For this purpose, human prostate cancer PC3 cells were transfected with the luciferase gene fused with an oxygen-dependent degradation domain (ODD-luc) and a variant of the enhanced green fluorescent protein (EGFP). Both ODD-luciferase and EGFP were under the promotion of a poly-hypoxia-response element sequence (5xHRE). The cells constitutively expressed tdTomato red fluorescent protein. For validating the imaging strategy, cells were incubated under hypoxia (1% O2) for 48 hours and then reoxygenated. The luciferase activity of PC3-HRE-EGFP/HRE-ODD-luc/tdtomato cells detected by bioluminescent imaging rapidly decreased after reoxygenation, whereas EGFP levels in these cells remained stable for several hours. After in vitro validation, PC3-HRE-EGFP/HRE-ODD-luc/tdtomato tumors were implanted subcutaneously and orthotopically in nude male mice and imaged in vivo and ex vivo using optical imaging in proof-of-principle studies to demonstrate differences in optical patterns between EGFP expression and bioluminescence. This novel "timer" imaging strategy of combining the short-lived ODD-luciferase and the long-lived EGFP can provide a time frame of HRE activation in PC3 prostate cancer cells and will be useful to understand the temporal changes in hypoxia and HIF activity during cancer progression and following treatments including HIF targeting strategies. PMID:26696369

Phylogenetic ecology at world scale, a new fusion between ecology and evolution.

PubMed

Westoby, Mark

2006-07-01

One fusion between ecology and evolution is well established, under the title of population biology. The years 2006-2020 will see a new fusion, likely to prove equally creative. Inputs from ecology to this second fusion will be worldwide data sets for ecological traits across many species. Inputs from evolution will be phylogenetic trees with well-resolved topology and with increasingly tight geological dates for each branch point. There will be unification of two aims: first to explain the spread of different ways of making a living, across the range of present-day species; and second, to narrate the evolutionary history that has led up to present-day ecology.

Half-life determination for {sup 108}Ag and {sup 110}Ag

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

Zahn, Guilherme S.; Genezini, Frederico A.

2014-11-11

In this work, the half-life of the short-lived silver radionuclides {sup 108}Ag and {sup 110}Ag were measured by following the activity of samples after they were irradiated in the IEA-R1 reactor. The results were then fitted using a non-paralizable dead time correction to the regular exponential decay and the individual half-life values obtained were then analyzed using both the Normalized Residuals and the Rajeval techniques, in order to reach the most exact and precise final values. To check the validity of dead-time correction, a second correction method was also employed by means of counting a long-lived {sup 60}Co radioactive sourcemore » together with the samples as a livetime chronometer. The final half-live values obtained using both dead-time correction methods were in good agreement, showing that the correction was properly assessed. The results obtained are partially compatible with the literature values, but with a lower uncertainty, and allow a discussion on the last ENSDF compilations' values.« less

Environmental and ecological changes associated with a marina.

PubMed

Rivero, Natalie K; Dafforn, Katherine A; Coleman, Melinda A; Johnston, Emma L

2013-01-01

Anthropogenic modifications to waterways are common and their ecological consequences must be understood to effectively conserve local biodiversity. The facilitation of recreational boating activities often requires substantial alteration of natural areas, however the environmental and ecological consequences of such alterations are rarely described in the scientific literature. In this study, ecological and physico-chemical conditions were investigated in a recreational boating marina, located inside a marine park on the south-east coast of Australia. Recruitment panels were deployed for 8 weeks both inside and outside the marina, and differences in the composition of the developing fouling communities were observed. The recruitment of taxa, which often have short-lived larvae, was increased inside the marina (bryozoans, spirorbids and sponges) while the recruitment of taxa, which often have longer-lived larvae, was reduced or absent (barnacles, solitary ascidians and non-spirorbid polychaetes). Differences were also observed in environmental conditions inside the marina cf. directly outside. The marina environment had higher turbidity, temperature and pH along with higher concentrations of lead and copper in suspended sediments, while flow rates and trapped sediment loads were reduced inside the marina. The differences observed in the study suggest that there may be marked environmental changes associated with marina developments. The potential ecological consequences of these changes should be a primary consideration during the planning process, particularly for developments in locations of notable ecological value.

Fecal glucocorticoids reflect socio-ecological and anthropogenic stressors in the lives of wild spotted hyenas.

PubMed

Van Meter, Page E; French, Jeffrey A; Dloniak, Stephanie M; Watts, Heather E; Kolowski, Joseph M; Holekamp, Kay E

2009-02-01

Our aim was to identify natural and anthropogenic influences on the stress physiology of large African carnivores, using wild spotted hyenas (Crocuta crocuta) as model animals. With both longitudinal data from a single social group, and cross-sectional data from multiple groups, we used fecal glucocorticoids (fGC) to examine potential stressors among spotted hyenas. Longitudinal data from adult members of a group living on the edge of the Masai Mara National Reserve, Kenya, revealed that fGC concentrations were elevated during two periods of social upheaval among adults, especially among younger females; however, prey availability, rainfall, and presence of lions did not influence fGC concentrations among hyenas. Our results suggested that anthropogenic disturbance in the form of pastoralist activity, but not tourism, influenced fGC concentrations among adult male hyenas; rising concentrations of fGC among males over 12 years were significantly correlated with increasing human population density along the edge of the group's home range. As hyenas from this social group were frequently exposed to anthropogenic disturbance, we compared fGC concentrations among these hyenas with those obtained concurrently from hyenas living in three other groups undisturbed by pastoralist activity. We found that fGC concentrations from the undisturbed groups were significantly lower than those in the disturbed group, and we were able to rule out tourism and ecological stressors as sources of variation in fGC among the populations. Thus it appears that both social instability and anthropogenic disturbance, but not the ecological variables examined, elevate fGC concentrations and represent stressors for wild spotted hyenas. Further work will be necessary to determine whether interpopulation variation in stress physiology predicts population decline in groups exposed to intensive anthropogenic disturbance.

Ecological effects of ocean acidification and habitat complexity on reef-associated macroinvertebrate communities.

PubMed

Fabricius, K E; De'ath, G; Noonan, S; Uthicke, S

2014-01-22

The ecological effects of ocean acidification (OA) from rising atmospheric carbon dioxide (CO2) on benthic marine communities are largely unknown. We investigated in situ the consequences of long-term exposure to high CO2 on coral-reef-associated macroinvertebrate communities around three shallow volcanic CO2 seeps in Papua New Guinea. The densities of many groups and the number of taxa (classes and phyla) of macroinvertebrates were significantly reduced at elevated CO2 (425-1100 µatm) compared with control sites. However, sensitivities of some groups, including decapod crustaceans, ascidians and several echinoderms, contrasted with predictions of their physiological CO2 tolerances derived from laboratory experiments. High CO2 reduced the availability of structurally complex corals that are essential refugia for many reef-associated macroinvertebrates. This loss of habitat complexity was also associated with losses in many macroinvertebrate groups, especially predation-prone mobile taxa, including crustaceans and crinoids. The transition from living to dead coral as substratum and habitat further altered macroinvertebrate communities, with far more taxa losing than gaining in numbers. Our study shows that indirect ecological effects of OA (reduced habitat complexity) will complement its direct physiological effects and together with the loss of coral cover through climate change will severely affect macroinvertebrate communities in coral reefs.

Ecological effects of ocean acidification and habitat complexity on reef-associated macroinvertebrate communities

PubMed Central

Fabricius, K. E.; De'ath, G.; Noonan, S.; Uthicke, S.

2014-01-01

The ecological effects of ocean acidification (OA) from rising atmospheric carbon dioxide (CO2) on benthic marine communities are largely unknown. We investigated in situ the consequences of long-term exposure to high CO2 on coral-reef-associated macroinvertebrate communities around three shallow volcanic CO2 seeps in Papua New Guinea. The densities of many groups and the number of taxa (classes and phyla) of macroinvertebrates were significantly reduced at elevated CO2 (425–1100 µatm) compared with control sites. However, sensitivities of some groups, including decapod crustaceans, ascidians and several echinoderms, contrasted with predictions of their physiological CO2 tolerances derived from laboratory experiments. High CO2 reduced the availability of structurally complex corals that are essential refugia for many reef-associated macroinvertebrates. This loss of habitat complexity was also associated with losses in many macroinvertebrate groups, especially predation-prone mobile taxa, including crustaceans and crinoids. The transition from living to dead coral as substratum and habitat further altered macroinvertebrate communities, with far more taxa losing than gaining in numbers. Our study shows that indirect ecological effects of OA (reduced habitat complexity) will complement its direct physiological effects and together with the loss of coral cover through climate change will severely affect macroinvertebrate communities in coral reefs. PMID:24307670

SIBLING CONFLICTS IN FULL- AND HALF-SIBLING HOUSEHOLDS IN THE UK.

PubMed

Tanskanen, Antti O; Danielsbacka, Mirkka; Jokela, Markus; Rotkirch, Anna

2017-01-01

Sibling relations are by nature ambivalent with high levels of both altruistic helping and competition. Higher relatedness is often assumed to reduce the occurrence of conflicts between siblings, but evidence of this has been scarce and mixed. Siblings typically compete over resources and parental attention, and parental constellations vary with sibship types. Since full-siblings compete over the same two biological parents, while half-siblings have only one shared biological parent and often a higher number of parents overall, it is hypothesized that conflicts are more common between full- than half-siblings. This study tested this assumption using the British Millennium Cohort Study (n=7527 children at age 11). Conflicts were measured as children's reports of how much siblings picked on and hurt each other. Households with full-siblings only, maternal half-siblings only, and both full- and maternal half-siblings were compared. The results show that children who were living with only their full-siblings were more likely to experience sibling conflicts compared with children living with their maternal half-siblings only. This was the case also after controlling for several potentially confounding variables. The results suggest that differential access to parental resources of available biological and step-parents may explain the higher amount of sibling conflict between full- compared with maternal half-siblings.

[Ecological effects of bagging on actinidia fruits].

PubMed

Chen, Zhijie; Zhang, Shulian; Znang, Feng; Shi, Yongqiang

2003-11-01

Studies on the ecological effects of bagging on actinidia fruits showed that under different types of bagging, the ecological effects on actinidia fruits were different. Bagging with membrane changed the conditions of temperature and humidity. The inside temperature raised by 0.7-0.9 degree C, humidity increased by 10.8%-11.8%, single fruit weight increased by 25.7%-37.7%, commercial fruit rate raised by 20.4%-30.1%, percentage of diseases and pests decreased by 85.7%-90.2%, and storage property was good. Additionally, the application rate of chemical pesticide was reduce by 72.2%, and the concentration of remnant pesticide inside fruits was only 0.31% mg.kg-1, which was decreased by 90.0%. The chemical pesticide pollution in ecological circumstance and actinidia fruits both reduced. It would be a new way for the rgeen fruits production in the future. Bagging with paper has obvious negative effects.

Avian Influenza Ecology in North Atlantic Sea Ducks: Not All Ducks Are Created Equal

PubMed Central

Hall, Jeffrey S.; Russell, Robin E.; Franson, J. Christian; Soos, Catherine; Dusek, Robert J.; Allen, R. Bradford; Nashold, Sean W.; TeSlaa, Joshua L.; Jónsson, Jón Eínar; Ballard, Jennifer R.; Harms, Naomi Jane; Brown, Justin D.

2015-01-01

Wild waterfowl are primary reservoirs of avian influenza viruses (AIV). However the role of sea ducks in the ecology of avian influenza, and how that role differs from freshwater ducks, has not been examined. We obtained and analyzed sera from North Atlantic sea ducks and determined the seroprevalence in those populations. We also tested swab samples from North Atlantic sea ducks for the presence of AIV. We found relatively high serological prevalence (61%) in these sea duck populations but low virus prevalence (0.3%). Using these data we estimated that an antibody half-life of 141 weeks (3.2 years) would be required to attain these prevalences. These findings are much different than what is known in freshwater waterfowl and have implications for surveillance efforts, AIV in marine environments, and the roles of sea ducks and other long-lived waterfowl in avian influenza ecology. PMID:26677841

Avian Influenza Ecology in North Atlantic Sea Ducks: Not All Ducks Are Created Equal.

PubMed

Hall, Jeffrey S; Russell, Robin E; Franson, J Christian; Soos, Catherine; Dusek, Robert J; Allen, R Bradford; Nashold, Sean W; TeSlaa, Joshua L; Jónsson, Jón Eínar; Ballard, Jennifer R; Harms, Naomi Jane; Brown, Justin D

2015-01-01

Wild waterfowl are primary reservoirs of avian influenza viruses (AIV). However the role of sea ducks in the ecology of avian influenza, and how that role differs from freshwater ducks, has not been examined. We obtained and analyzed sera from North Atlantic sea ducks and determined the seroprevalence in those populations. We also tested swab samples from North Atlantic sea ducks for the presence of AIV. We found relatively high serological prevalence (61%) in these sea duck populations but low virus prevalence (0.3%). Using these data we estimated that an antibody half-life of 141 weeks (3.2 years) would be required to attain these prevalences. These findings are much different than what is known in freshwater waterfowl and have implications for surveillance efforts, AIV in marine environments, and the roles of sea ducks and other long-lived waterfowl in avian influenza ecology.

Avian influenza ecology in North Atlantic sea ducks: Not all ducks are created equal

USGS Publications Warehouse

Hall, Jeffrey S.; Russell, Robin E.; Franson, J. Christian; Soos, Catherine; Dusek, Robert J.; Allen, R. Bradford; Nashold, Sean W.; Teslaa, Joshua L.; Jónsson, Jón Einar; Ballard, Jennifer R.; Harms, Naomi Jnae; Brown, Justin D.

2015-01-01

Wild waterfowl are primary reservoirs of avian influenza viruses (AIV). However the role of sea ducks in the ecology of avian influenza, and how that role differs from freshwater ducks, has not been examined. We obtained and analyzed sera from North Atlantic sea ducks and determined the seroprevalence in those populations. We also tested swab samples from North Atlantic sea ducks for the presence of AIV. We found relatively high serological prevalence (61%) in these sea duck populations but low virus prevalence (0.3%). Using these data we estimated that an antibody half-life of 141 weeks (3.2 years) would be required to attain these prevalences. These findings are much different than what is known in freshwater waterfowl and have implications for surveillance efforts, AIV in marine environments, and the roles of sea ducks and other long-lived waterfowl in avian influenza ecology.

Pleistocene and ecological effects on continental-scale genetic differentiation in the bobcat (Lynx rufus).

PubMed

Reding, Dawn M; Bronikowski, Anne M; Johnson, Warren E; Clark, William R

2012-06-01

The potential for widespread, mobile species to exhibit genetic structure without clear geographic barriers is a topic of growing interest. Yet the patterns and mechanisms of structure--particularly over broad spatial scales--remain largely unexplored for these species. Bobcats occur across North America and possess many characteristics expected to promote gene flow. To test whether historical, topographic or ecological factors have influenced genetic differentiation in this species, we analysed 1 kb mtDNA sequence and 15 microsatellite loci from over 1700 samples collected across its range. The primary signature in both marker types involved a longitudinal cline with a sharp transition, or suture zone, occurring along the Great Plains. Thus, the data distinguished bobcats in the eastern USA from those in the western half, with no obvious physical barrier to gene flow. Demographic analyses supported a scenario of expansion from separate Pleistocene refugia, with the Great Plains representing a zone of secondary contact. Substructure within the two main lineages likely reflected founder effects, ecological factors, anthropogenic/topographic effects or a combination of these forces. Two prominent topographic features, the Mississippi River and Rocky Mountains, were not supported as significant genetic barriers. Ecological regions and environmental correlates explained a small but significant proportion of genetic variation. Overall, results implicate historical processes as the primary cause of broad-scale genetic differentiation, but contemporary forces seem to also play a role in promoting and maintaining structure. Despite the bobcat's mobility and broad niche, large-scale landscape changes have contributed to significant and complex patterns of genetic structure. © 2012 Blackwell Publishing Ltd.

Linking effects of anthropogenic debris to ecological impacts

PubMed Central

Browne, Mark Anthony; Underwood, A. J.; Chapman, M. G.; Williams, Rob; Thompson, Richard C.; van Franeker, Jan A.

2015-01-01

Accelerated contamination of habitats with debris has caused increased effort to determine ecological impacts. Strikingly, most work on organisms focuses on sublethal responses to plastic debris. This is controversial because (i) researchers have ignored medical insights about the mechanisms that link effects of debris across lower levels of biological organization to disease and mortality, and (ii) debris is considered non-hazardous by policy-makers, possibly because individuals can be injured or removed from populations and assemblages without ecological impacts. We reviewed the mechanisms that link effects of debris across lower levels of biological organization to assemblages and populations. Using plastic, we show microplastics reduce the ‘health’, feeding, growth and survival of ecosystem engineers. Larger debris alters assemblages because fishing-gear and tyres kill animals and damage habitat-forming plants, and because floating bottles facilitate recruitment and survival of novel taxa. Where ecological linkages are not known, we show how to establish hypothetical links by synthesizing studies to assess the likelihood of impacts. We also consider how population models examine ecological linkages and guide management of ecological impacts. We show that by focusing on linkages to ecological impacts rather than the presence of debris and its sublethal impacts, we could reduce threats posed by debris. PMID:25904661

Persistence and Effective Half-Life of Chemical Warfare Agent VX on Grass Foliage

DTIC Science & Technology

2017-08-01

obtain results applicable to VX- contaminated battlefields. The Effective Half-Life of VX on grass foliage was determined as the net effect of factors...Soldiers on VX- contaminated battlefields. 15. SUBJECT TERMS Chemical warfare agent (CWA) Agent–plant Echinochloa crus-galli Foliage Effective Half...The use of either trade or manufacturers ’ names in this report does not constitute an official endorsement of any commercial products. This report may

The Passive Yet Successful Way of Planktonic Life: Genomic and Experimental Analysis of the Ecology of a Free-Living Polynucleobacter Population

PubMed Central

Hahn, Martin W.; Scheuerl, Thomas; Jezberová, Jitka; Koll, Ulrike; Jezbera, Jan; Šimek, Karel; Vannini, Claudia; Petroni, Giulio; Wu, Qinglong L.

2012-01-01

Background The bacterial taxon Polynucleobacter necessarius subspecies asymbioticus represents a group of planktonic freshwater bacteria with cosmopolitan and ubiquitous distribution in standing freshwater habitats. These bacteria comprise <1% to 70% (on average about 20%) of total bacterioplankton cells in various freshwater habitats. The ubiquity of this taxon was recently explained by intra-taxon ecological diversification, i.e. specialization of lineages to specific environmental conditions; however, details on specific adaptations are not known. Here we investigated by means of genomic and experimental analyses the ecological adaptation of a persistent population dwelling in a small acidic pond. Findings The investigated population (F10 lineage) contributed on average 11% to total bacterioplankton in the pond during the vegetation periods (ice-free period, usually May to November). Only a low degree of genetic diversification of the population could be revealed. These bacteria are characterized by a small genome size (2.1 Mb), a relatively small number of genes involved in transduction of environmental signals, and the lack of motility and quorum sensing. Experiments indicated that these bacteria live as chemoorganotrophs by mainly utilizing low-molecular-weight substrates derived from photooxidation of humic substances. Conclusions Evolutionary genome streamlining resulted in a highly passive lifestyle so far only known among free-living bacteria from pelagic marine taxa dwelling in environmentally stable nutrient-poor off-shore systems. Surprisingly, such a lifestyle is also successful in a highly dynamic and nutrient-richer environment such as the water column of the investigated pond, which was undergoing complete mixis and pronounced stratification in diurnal cycles. Obviously, metabolic and ecological versatility is not a prerequisite for long-lasting establishment of abundant bacterial populations under highly dynamic environmental conditions. Caution

The passive yet successful way of planktonic life: genomic and experimental analysis of the ecology of a free-living polynucleobacter population.

PubMed

Hahn, Martin W; Scheuerl, Thomas; Jezberová, Jitka; Koll, Ulrike; Jezbera, Jan; Šimek, Karel; Vannini, Claudia; Petroni, Giulio; Wu, Qinglong L

2012-01-01

The bacterial taxon Polynucleobacter necessarius subspecies asymbioticus represents a group of planktonic freshwater bacteria with cosmopolitan and ubiquitous distribution in standing freshwater habitats. These bacteria comprise <1% to 70% (on average about 20%) of total bacterioplankton cells in various freshwater habitats. The ubiquity of this taxon was recently explained by intra-taxon ecological diversification, i.e. specialization of lineages to specific environmental conditions; however, details on specific adaptations are not known. Here we investigated by means of genomic and experimental analyses the ecological adaptation of a persistent population dwelling in a small acidic pond. The investigated population (F10 lineage) contributed on average 11% to total bacterioplankton in the pond during the vegetation periods (ice-free period, usually May to November). Only a low degree of genetic diversification of the population could be revealed. These bacteria are characterized by a small genome size (2.1 Mb), a relatively small number of genes involved in transduction of environmental signals, and the lack of motility and quorum sensing. Experiments indicated that these bacteria live as chemoorganotrophs by mainly utilizing low-molecular-weight substrates derived from photooxidation of humic substances. Evolutionary genome streamlining resulted in a highly passive lifestyle so far only known among free-living bacteria from pelagic marine taxa dwelling in environmentally stable nutrient-poor off-shore systems. Surprisingly, such a lifestyle is also successful in a highly dynamic and nutrient-richer environment such as the water column of the investigated pond, which was undergoing complete mixis and pronounced stratification in diurnal cycles. Obviously, metabolic and ecological versatility is not a prerequisite for long-lasting establishment of abundant bacterial populations under highly dynamic environmental conditions. Caution should be exercised when

Excretion Profiles and Half-Lives of Ten Urinary Polycyclic Aromatic Hydrocarbon Metabolites after Dietary Exposure

PubMed Central

Li, Zheng; Romanoff, Lovisa; Bartell, Scott; Pittman, Erin N.; Trinidad, Debra A.; McClean, Michael; Webster, Thomas F.; Sjödin, Andreas

2015-01-01

Human exposure to polycyclic aromatic hydrocarbons (PAHs) can be assessed by biomonitoring of their urinary mono-hydroxylated metabolites (OH-PAHs). Limited information exists on the human pharmacokinetics of OH-PAHs. This study aimed to investigate the excretion half-life of 1-hydroxypyrene (1-PYR), the most used biomarker for PAH exposure, and 9 other OH-PAHs following a dietary exposure in 9 non-smoking volunteers with no occupational exposure to PAHs. Each person avoided food with known high PAH-content during the study period, except for a high PAH-containing lunch (barbecued chicken) on the first day. Individual urine samples (n = 217) were collected from 15 hours before to 60 hours following the dietary exposure. Levels of all OH-PAHs in all subjects increased rapidly by 9–141 fold after the exposure, followed by a decrease consistent with first order kinetics, and returned to background levels 24–48 hours after the exposure. The average time to reach maximal concentration ranged from 3.1 h (1-naphthol) to 5.5 h (1-PYR). Creatinine-adjusted urine concentrations for each metabolite were analyzed using a non-linear mixed effects model including a term to estimate background exposure. The background-adjusted half-life estimate was 3.9 h for 1-PYR and ranged 2.5–6.1 h for the other 9 OH-PAHs, which in general, were shorter than those previously reported. The maximum concentrations after the barbecued chicken consumption were comparable to the levels found in reported occupational settings with known high PAH exposures. It is essential to consider the relatively short half-life, the timing of samples relative to exposures, and the effect of diet when conducting PAH exposure biomonitoring studies. PMID:22663094

Effect of Malathion on the Microbial Ecology of Activated Sludge

DTIC Science & Technology

2015-03-26

EFFECT OF MALATHION ON THE MICROBIAL ECOLOGY OF ACTIVATED SLUDGE THESIS Seth K. Martin, Senior Master Sergeant, USAF AFIT-ENV-MS-15-M-095 DEPARTMENT...Government and is not subject to copyright protection in the United States. AFIT-ENV-MS-15-M-095 EFFECT OF MALATHION ON THE MICROBIAL ECOLOGY OF ACTIVATED...UNLIMITED. AFIT-ENV-MS-15-M-095 EFFECT OF MALATHION ON THE MICROBIAL ECOLOGY OF ACTIVATED SLUDGE THESIS Seth K. Martin, B.S. Senior Master Sergeant

Increased volume of distribution for recombinant activated factor VII and longer plasma-derived factor VII half-life may explain their long lasting prophylactic effect.

PubMed

Mathijssen, Natascha C J; Masereeuw, Rosalinde; Holme, Pal Andre; van Kraaij, Marian G J; Laros-van Gorkom, Britta A P; Peyvandi, Flora; van Heerde, Waander L

2013-08-01

Prophylaxis with plasma-derived or recombinant activated factor VII is beneficial in severe factor VII deficiency. To understand why prophylactic treatment with both products is efficacious, we conducted a pharmacokinetic study. Ten factor VII deficient patients were treated with either recombinant activated (20 μg/kg) or plasma-derived (25 IU/kg) factor VII in a cross-over design. Pharmacokinetic parameters were analyzed through activated factor VII activity, factor VII clotting activity, and factor VII antigen levels on depicted time points. Factor VII activity half-lifes, determined by non-compartmental and one-compartmental analysis (results in brackets), were shorter for recombinant activated (1.4h; 0.7h) than for plasma-derived factor VII (6.8h; 3.2h); both recombinant activated (5.1h; 2.1h and plasma-derived factor VII (5.8h; 3.2h) resulted in longer half-lives of factor VII antigen. Activated factor VII half-lives (based on activated factor VII activity levels) were significantly higher compared to factor VII clotting activity (1.6h; 0.9h). Volumes of distribution were significantly higher for activated factor VII (236 ml/kg; 175 ml/kg, measured by activated factor VII) as compared to plasma-derived factor VII (206 ml/kg; 64 ml/kg, measured by factor FVII activity), suggesting a plasma- and extracellular fluid distribution for recombinant activated factor VII. Recombinant activated factor VII showed significantly shorter half-lifes than plasma-derived factor VII. Volumes of distribution were significantly higher for treatment with recombinant activated factor VII. The longer half-life for plasma-derived factor VII, compared to recombinant activated factor VII, and the increased volume of distribution for recombinant activated factor VII, compared to plasma-derived factor VII may further elucidate the beneficial effect of prophylactic treatment of both products. Copyright © 2013 Elsevier Ltd. All rights reserved.

Combining Optical Reporter Proteins with Different Half-lives to Detect Temporal Evolution of Hypoxia and Reoxygenation in Tumors.

PubMed

Danhier, Pierre; Krishnamachary, Balaji; Bharti, Santosh; Kakkad, Samata; Mironchik, Yelena; Bhujwalla, Zaver M

2015-12-01

Here we have developed a hypoxia response element driven imaging strategy that combined the hypoxia-driven expression of two optical reporters with different half-lives to detect temporal changes in hypoxia and hypoxia inducible factor (HIF) activity. For this purpose, human prostate cancer PC3 cells were transfected with the luciferase gene fused with an oxygen-dependent degradation domain (ODD-luc) and a variant of the enhanced green fluorescent protein (EGFP). Both ODD-luciferase and EGFP were under the promotion of a poly-hypoxia-response element sequence (5xHRE). The cells constitutively expressed tdTomato red fluorescent protein. For validating the imaging strategy, cells were incubated under hypoxia (1% O2) for 48 hours and then reoxygenated. The luciferase activity of PC3-HRE-EGFP/HRE-ODD-luc/tdtomato cells detected by bioluminescent imaging rapidly decreased after reoxygenation, whereas EGFP levels in these cells remained stable for several hours. After in vitro validation, PC3-HRE-EGFP/HRE-ODD-luc/tdtomato tumors were implanted subcutaneously and orthotopically in nude male mice and imaged in vivo and ex vivo using optical imaging in proof-of-principle studies to demonstrate differences in optical patterns between EGFP expression and bioluminescence. This novel "timer" imaging strategy of combining the short-lived ODD-luciferase and the long-lived EGFP can provide a time frame of HRE activation in PC3 prostate cancer cells and will be useful to understand the temporal changes in hypoxia and HIF activity during cancer progression and following treatments including HIF targeting strategies. Copyright © 2015 Nencki Institute of Experimental Biology, Polish Academy of Sciences,. Published by Elsevier Inc. All rights reserved.

Linking effects of anthropogenic debris to ecological impacts.

PubMed

Browne, Mark Anthony; Underwood, A J; Chapman, M G; Williams, Rob; Thompson, Richard C; van Franeker, Jan A

2015-05-22

Accelerated contamination of habitats with debris has caused increased effort to determine ecological impacts. Strikingly, most work on organisms focuses on sublethal responses to plastic debris. This is controversial because (i) researchers have ignored medical insights about the mechanisms that link effects of debris across lower levels of biological organization to disease and mortality, and (ii) debris is considered non-hazardous by policy-makers, possibly because individuals can be injured or removed from populations and assemblages without ecological impacts. We reviewed the mechanisms that link effects of debris across lower levels of biological organization to assemblages and populations. Using plastic, we show microplastics reduce the 'health', feeding, growth and survival of ecosystem engineers. Larger debris alters assemblages because fishing-gear and tyres kill animals and damage habitat-forming plants, and because floating bottles facilitate recruitment and survival of novel taxa. Where ecological linkages are not known, we show how to establish hypothetical links by synthesizing studies to assess the likelihood of impacts. We also consider how population models examine ecological linkages and guide management of ecological impacts. We show that by focusing on linkages to ecological impacts rather than the presence of debris and its sublethal impacts, we could reduce threats posed by debris. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Striking Effects of Storage Buffers on Apparent Half-Lives of the Activity of Pseudomonas aeruginosa Arylsulfatase.

PubMed

Li, Yuwei; Yang, Xiaolan; Wang, Deqiang; Hu, Xiaolei; Yuan, Mei; Pu, Jun; Zhan, Chang-Guo; Yang, Zhaoyong; Liao, Fei

2016-08-01

To obtain the label enzyme for enzyme-linked-immunoabsorbent-assay of two components each time in one well with conventional microplate readers, molecular engineering of Pseudomonas aeruginosa arylsulfatase (PAAS) is needed. To compare thermostability of PAAS/mutants of limited purity, effects of buffers on the half-activity time (t 0.5) at 37 °C were tested. At pH 7.4, PAAS showed non-exponential decreases of activity, with the apparent t 0.5 of ~6.0 days in 50 mM HEPES, but ~42 days in 10 mM sodium borate with >85 % activity after 15 days; protein concentrations in both buffers decreased at slower rates after there were significant decreases of activities. Additionally, the apparent t 0.5 of PAAS was ~14 days in 50 mM Tris-HCl, and ~21 days in 10 mM sodium phosphate. By sodium dodecyl-polyacrylamide gel electrophoresis, the purified PAAS gave single polypeptide; after storage for 14 days at 37 °C, there were many soluble and insoluble fragmented polypeptides in the HEPES buffer, but just one principal insoluble while negligible soluble fragmented polypeptides in the borate buffer. Of tested mutants in the neutral borate buffer, rates for activity decreases and polypeptide degradation were slower than in the HEPES buffer. Hence, dilute neutral borate buffers were favorable for examining thermostability of PAAS/mutants.

Effects of Vegetarian Nutrition–A Nutrition Ecological Perspective

PubMed Central

Metz, Martina; Hoffmann, Ingrid

2010-01-01

Although vegetarian nutrition is a complex issue, the multidimensionality and interrelatedness of its effects are rarely explored. This article aims to demonstrate the complexity of vegetarian nutrition by means of the nutrition ecological modeling technique NutriMod. The integrative qualitative cause-effect model, which is based on scientific literature, provides a comprehensive picture of vegetarian nutrition. The nutrition ecological perspective offers a basis for the assessment of the effects of worldwide developments concerning shifts in diets and the effects of vegetarian nutrition on global problems like climate change. Furthermore, new research areas on the complexity of vegetarian nutrition can be identified. PMID:22254037

ESTIMATION OF EFFECTIVE DOSE FROM EXTERNAL EXPOSURE DUE TO SHORT-LIVED NUCLIDES IN THE PREFECTURES SURROUNDING FUKUSHIMA.

PubMed

Miyatake, Hirokazu; Yoshizawa, Nobuaki; Suzuki, Gen

2018-05-11

The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident resulted in a release of radionuclides into the environment. Since the accident, measurements of radiation in the environment such as air dose rate and deposition density of radionuclides have been performed by various organizations and universities. In particular, Japan Atomic Energy Agency (JAEA) has been performing observations of air dose rate using a car-borne survey system continuously over widespread areas. Based on the data measured by JAEA, we estimated effective dose from external exposure in the prefectures surrounding Fukushima. Since car-borne survey started a few months after the accident, the main contribution to measured data comes from 137Cs and 134Cs whose half-lives are relatively long. Using air dose rate of 137Cs and 134Cs and the ratio of deposition density of short-lived nuclides to that of 137Cs and 134Cs, we also estimated contributions to the effective dose from other short-lived nuclides.

An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm.

PubMed

Dinerstein, Eric; Olson, David; Joshi, Anup; Vynne, Carly; Burgess, Neil D; Wikramanayake, Eric; Hahn, Nathan; Palminteri, Suzanne; Hedao, Prashant; Noss, Reed; Hansen, Matt; Locke, Harvey; Ellis, Erle C; Jones, Benjamin; Barber, Charles Victor; Hayes, Randy; Kormos, Cyril; Martin, Vance; Crist, Eileen; Sechrest, Wes; Price, Lori; Baillie, Jonathan E M; Weeden, Don; Suckling, Kierán; Davis, Crystal; Sizer, Nigel; Moore, Rebecca; Thau, David; Birch, Tanya; Potapov, Peter; Turubanova, Svetlana; Tyukavina, Alexandra; de Souza, Nadia; Pintea, Lilian; Brito, José C; Llewellyn, Othman A; Miller, Anthony G; Patzelt, Annette; Ghazanfar, Shahina A; Timberlake, Jonathan; Klöser, Heinz; Shennan-Farpón, Yara; Kindt, Roeland; Lillesø, Jens-Peter Barnekow; van Breugel, Paulo; Graudal, Lars; Voge, Maianna; Al-Shammari, Khalaf F; Saleem, Muhammad

2017-06-01

We assess progress toward the protection of 50% of the terrestrial biosphere to address the species-extinction crisis and conserve a global ecological heritage for future generations. Using a map of Earth's 846 terrestrial ecoregions, we show that 98 ecoregions (12%) exceed Half Protected; 313 ecoregions (37%) fall short of Half Protected but have sufficient unaltered habitat remaining to reach the target; and 207 ecoregions (24%) are in peril, where an average of only 4% of natural habitat remains. We propose a Global Deal for Nature-a companion to the Paris Climate Deal-to promote increased habitat protection and restoration, national- and ecoregion-scale conservation strategies, and the empowerment of indigenous peoples to protect their sovereign lands. The goal of such an accord would be to protect half the terrestrial realm by 2050 to halt the extinction crisis while sustaining human livelihoods.

[Assessment of ecological environment effects of coastal development in Hebei Province, China].

PubMed

Cui, Li-Tuo; Li, Zhi-Wei

2014-07-01

Through the analysis of the development activities and the ecological environment in coastal of Hebei Province, China, an index system for evaluating the ecological environment effect, composed of 28 indices, was set up by the pressure, state and response subsystems. Using the comprehensive index evaluation method, the integrated effects of ecological environment index (EI) was calculated and its grading criterion was founded. The results showed that the ecological environment effect of Hebei Province coastal development varied from being relatively small, normal and then relatively large from 1984 to 2010, and its acceptance degree evolved from being acceptable to being unacceptable. Because the resource and environment pressures caused by coastal development were serious and a delay existed in the state relative to the response, the improvement of various measures in the response subsystem did not show a positive effect on the state, and the environmental quality of ocean showed a degrading trend. Due to the differences in coastal development pattern and strength, the ecological environment effect of development activities showed some spatial differences. The ecological environment effect of Qinhuangdao coastal development was the minimum, followed by Cangzhou and Tangshan. Cangzhou and Tangshan had reached unacceptable levels and needed to further strengthen the restoration and protection of ecological environment.

An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm

PubMed Central

Olson, David; Joshi, Anup; Burgess, Neil D.; Wikramanayake, Eric; Hahn, Nathan; Palminteri, Suzanne; Hedao, Prashant; Noss, Reed; Hansen, Matt; Locke, Harvey; Ellis, Erle C; Jones, Benjamin; Barber, Charles Victor; Hayes, Randy; Kormos, Cyril; Martin, Vance; Crist, Eileen; Sechrest, Wes; Price, Lori; Baillie, Jonathan E. M.; Weeden, Don; Suckling, Kierán; Davis, Crystal; Sizer, Nigel; Moore, Rebecca; Thau, David; Birch, Tanya; Potapov, Peter; Turubanova, Svetlana; Tyukavina, Alexandra; de Souza, Nadia; Pintea, Lilian; Brito, José C.; Llewellyn, Othman A.; Miller, Anthony G.; Patzelt, Annette; Ghazanfar, Shahina A.; Timberlake, Jonathan; Klöser, Heinz; Shennan-Farpón, Yara; Kindt, Roeland; Lillesø, Jens-Peter Barnekow; van Breugel, Paulo; Graudal, Lars; Voge, Maianna; Al-Shammari, Khalaf F.; Saleem, Muhammad

2017-01-01

Abstract We assess progress toward the protection of 50% of the terrestrial biosphere to address the species-extinction crisis and conserve a global ecological heritage for future generations. Using a map of Earth's 846 terrestrial ecoregions, we show that 98 ecoregions (12%) exceed Half Protected; 313 ecoregions (37%) fall short of Half Protected but have sufficient unaltered habitat remaining to reach the target; and 207 ecoregions (24%) are in peril, where an average of only 4% of natural habitat remains. We propose a Global Deal for Nature—a companion to the Paris Climate Deal—to promote increased habitat protection and restoration, national- and ecoregion-scale conservation strategies, and the empowerment of indigenous peoples to protect their sovereign lands. The goal of such an accord would be to protect half the terrestrial realm by 2050 to halt the extinction crisis while sustaining human livelihoods. PMID:28608869

Simplified half-life methods for the analysis of kinetic data

NASA Technical Reports Server (NTRS)

Eberhart, J. G.; Levin, E.

1988-01-01

The analysis of reaction rate data has as its goal the determination of the order rate constant which characterize the data. Chemical reactions with one reactant and present simplified methods for accomplishing this goal are considered. The approaches presented involve the use of half lives or other fractional lives. These methods are particularly useful for the more elementary discussions of kinetics found in general and physical chemistry courses.

[Urban ecological risk assessment: a review].

PubMed

Wang, Mei-E; Chen, Wei-Ping; Peng, Chi

2014-03-01

With the development of urbanization and the degradation of urban living environment, urban ecological risks caused by urbanization have attracted more and more attentions. Based on urban ecology principles and ecological risk assessment frameworks, contents of urban ecological risk assessment were reviewed in terms of driven forces, risk resources, risk receptors, endpoints and integrated approaches for risk assessment. It was suggested that types and degrees of urban economical and social activities were the driven forces for urban ecological risks. Ecological functional components at different levels in urban ecosystems as well as the urban system as a whole were the risk receptors. Assessment endpoints involved in changes of urban ecological structures, processes, functional components and the integrity of characteristic and function. Social-ecological models should be the major approaches for urban ecological risk assessment. Trends for urban ecological risk assessment study should focus on setting a definite protection target and criteria corresponding to assessment endpoints, establishing a multiple-parameter assessment system and integrative assessment approaches.

Social Work in the Ecological Crisis.

ERIC Educational Resources Information Center

Berger, Raymond M.; Kelly, James J.

1993-01-01

Notes that, with advent of modern technology, human activity has altered biosphere in ways that are harmful to living systems. Contends that social work can play important role in facilitating human adaptation to such ecological change and that, to do so, profession will need to articulate values and purposes that encompass ecological concerns.…

Primate dental ecology: How teeth respond to the environment.

PubMed

Cuozzo, Frank P; Ungar, Peter S; Sauther, Michelle L

2012-06-01

Teeth are central for the study of ecology, as teeth are at the direct interface between an organism and its environment. Recent years have witnessed a rapid growth in the use of teeth to understand a broad range of topics in living and fossil primate biology. This in part reflects new techniques for assessing ways in which teeth respond to, and interact with, an organism's environment. Long-term studies of wild primate populations that integrate dental analyses have also provided a new context for understanding primate interactions with their environments. These new techniques and long-term field studies have allowed the development of a new perspective-dental ecology. We define dental ecology as the broad study of how teeth respond to, or interact with, the environment. This includes identifying patterns of dental pathology and tooth use-wear, as they reflect feeding ecology, behavior, and habitat variation, including areas impacted by anthropogenic disturbance, and how dental development can reflect environmental change and/or stress. The dental ecology approach, built on collaboration between dental experts and ecologists, holds the potential to provide an important theoretical and practical framework for inferring ecology and behavior of fossil forms, for assessing environmental change in living populations, and for understanding ways in which habitat impacts primate growth and development. This symposium issue brings together experts on dental morphology, growth and development, tooth wear and health, primate ecology, and paleontology, to explore the broad application of dental ecology to questions of how living and fossil primates interact with their environments. Copyright © 2012 Wiley Periodicals, Inc.

Transfer factors and effective half-lives of (134)Cs and (137)Cs in different environmental sample types obtained from Northern Finland: case Fukushima accident.

PubMed

Koivurova, Matias; Leppänen, Ari-Pekka; Kallio, Antti

2015-08-01

The Fukushima NPP accident caused a small but detectable cesium fallout in northern Finland, of the order of 1 Bq/m(2). This fallout transferred further to soil, water, flora and fauna. By using modern HPGe detector systems traces of (134)Cs from the Fukushima fallout were observed in various samples of biota. In northern Finland different types of environmental samples such as reindeer meat, berries, fish, lichens and wolf were collected during 2011-2013. The observed (134)Cs concentrations varied from 0.1 Bq/kg to a few Bq/kg. By using the known (134)Cs/(137)Cs ratio observed in Fukushima fallout the increase of the Fukushima accident to the (137)Cs concentrations was found to vary from 0.06 % to 6.9 % depending on the sample type. The aggregated transfer factors (Tag) and effective half-lives (Teff) for (134)Cs and (137)Cs were also determined and then compared with known values found from earlier studies which are calculated based on the fallout from the Chernobyl accident. Generally, the Tag and Teff values determined in this study were found to agree with the values found in the earlier studies. The Teff values were sample-type specific and were found to vary from 0.91 to 2.1 years for (134)Cs and the estimates for (137)Cs ranged between 1.6 and 19 years. Interestingly, the ground lichens had the longest Teff whereas the beard lichen had the shortest. In fauna, highest Tag values were determined for wolf meat ranging between 1.0 and 2.2 m(2)/kg. In flora, the highest Tag values were determined for beard lichens, ranging from 1.9 m(2)/kg to 3.5 m(2)/kg. Copyright © 2015 Elsevier Ltd. All rights reserved.

Half-lives and branchings for {beta}-delayed neutron emission for neutron-rich Co-Cu isotopes in the r-process

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

Hosmer, P.; Estrade, A.; Montes, F.

The {beta} decays of very neutron-rich nuclides in the Co-Zn region were studied experimentally at the National Superconducting Cyclotron Laboratory using the NSCL {beta}-counting station in conjunction with the neutron detector NERO. We measured the branchings for {beta}-delayed neutron emission (P{sub n} values) for {sup 74}Co (18{+-}15%) and {sup 75-77}Ni (10{+-}2.8%, 14{+-}3.6%, and 30{+-}24%, respectively) for the first time, and remeasured the P{sub n} values of {sup 77-79}Cu, {sup 79,81}Zn, and {sup 82}Ga. For {sup 77-79}Cu and for {sup 81}Zn we obtain significantly larger P{sub n} values compared to previous work. While the new half-lives for the Ni isotopes frommore » this experiment had been reported before, we present here in addition the first half-life measurements of {sup 75}Co (30{+-}11 ms) and {sup 80}Cu (170{sub -50}{sup +110} ms). Our results are compared with theoretical predictions, and their impact on various types of models for the astrophysical rapid neutron-capture process (r-process) is explored. We find that with our new data, the classical r-process model is better able to reproduce the A=78-80 abundance pattern inferred from the solar abundances. The new data also influence r-process models based on the neutrino-driven high-entropy winds in core collapse supernovae.« less

Educational Perspectives in the Ecological Paradigm--Possibilities and Limitations

ERIC Educational Resources Information Center

Lee, Sang-O

2007-01-01

In principle, education depends upon the understanding of human beings. Ecological studies can give us opportunities to understand humans more clearly (or scientifically). This truth emphasizes the importance of ecological education. In ecology, a human being is a part of nature. This is because all living beings are members of ecological…

Effect of Methodological and Ecological Approaches on Heterogeneity of Nest-Site Selection of a Long-Lived Vulture

PubMed Central

Moreno-Opo, Rubén; Fernández-Olalla, Mariana; Margalida, Antoni; Arredondo, Ángel; Guil, Francisco

2012-01-01

The application of scientific-based conservation measures requires that sampling methodologies in studies modelling similar ecological aspects produce comparable results making easier their interpretation. We aimed to show how the choice of different methodological and ecological approaches can affect conclusions in nest-site selection studies along different Palearctic meta-populations of an indicator species. First, a multivariate analysis of the variables affecting nest-site selection in a breeding colony of cinereous vulture (Aegypius monachus) in central Spain was performed. Then, a meta-analysis was applied to establish how methodological and habitat-type factors determine differences and similarities in the results obtained by previous studies that have modelled the forest breeding habitat of the species. Our results revealed patterns in nesting-habitat modelling by the cinereous vulture throughout its whole range: steep and south-facing slopes, great cover of large trees and distance to human activities were generally selected. The ratio and situation of the studied plots (nests/random), the use of plots vs. polygons as sampling units and the number of years of data set determined the variability explained by the model. Moreover, a greater size of the breeding colony implied that ecological and geomorphological variables at landscape level were more influential. Additionally, human activities affected in greater proportion to colonies situated in Mediterranean forests. For the first time, a meta-analysis regarding the factors determining nest-site selection heterogeneity for a single species at broad scale was achieved. It is essential to homogenize and coordinate experimental design in modelling the selection of species' ecological requirements in order to avoid that differences in results among studies would be due to methodological heterogeneity. This would optimize best conservation and management practices for habitats and species in a global context

Human neutrophil kinetics: modeling of stable isotope labeling data supports short blood neutrophil half-lives.

PubMed

Lahoz-Beneytez, Julio; Elemans, Marjet; Zhang, Yan; Ahmed, Raya; Salam, Arafa; Block, Michael; Niederalt, Christoph; Asquith, Becca; Macallan, Derek

2016-06-30

Human neutrophils have traditionally been thought to have a short half-life in blood; estimates vary from 4 to 18 hours. This dogma was recently challenged by stable isotope labeling studies with heavy water, which yielded estimates in excess of 3 days. To investigate this disparity, we generated new stable isotope labeling data in healthy adult subjects using both heavy water (n = 4) and deuterium-labeled glucose (n = 9), a compound with more rapid labeling kinetics. To interpret results, we developed a novel mechanistic model and applied it to previously published (n = 5) and newly generated data. We initially constrained the ratio of the blood neutrophil pool to the marrow precursor pool (ratio = 0.26; from published values). Analysis of heavy water data sets yielded turnover rates consistent with a short blood half-life, but parameters, particularly marrow transit time, were poorly defined. Analysis of glucose-labeling data yielded more precise estimates of half-life (0.79 ± 0.25 days; 19 hours) and marrow transit time (5.80 ± 0.42 days). Substitution of this marrow transit time in the heavy water analysis gave a better-defined blood half-life of 0.77 ± 0.14 days (18.5 hours), close to glucose-derived values. Allowing the ratio of blood neutrophils to mitotic neutrophil precursors (R) to vary yielded a best-fit value of 0.19. Reanalysis of the previously published model and data also revealed the origin of their long estimates for neutrophil half-life: an implicit assumption that R is very large, which is physiologically untenable. We conclude that stable isotope labeling in healthy humans is consistent with a blood neutrophil half-life of less than 1 day. © 2016 by The American Society of Hematology.

Ecology-centered experiences among children and adolescents: A qualitative and quantitative analysis

NASA Astrophysics Data System (ADS)

Orton, Judy

The present research involved two studies that considered ecology-centered experiences (i.e., experiences with living things) as a factor in children's environmental attitudes and behaviors and adolescents' ecological understanding. The first study (Study 1) examined how a community garden provides children in an urban setting the opportunity to learn about ecology through ecology-centered experiences. To do this, I carried out a yearlong ethnographic study at an urban community garden located in a large city in the Southeastern United States. Through participant observations and informal interviews of community garden staff and participants, I found children had opportunities to learn about ecology through ecology-centered experiences (e.g., interaction with animals) along with other experiences (e.g., playing games, reading books). In light of previous research that shows urban children have diminished ecological thought---a pattern of thought that privileges the relationship between living things---because of their lack of ecology-centered experiences (Coley, 2012), the present study may have implications for urban children to learn about ecology. As an extension of Study 1, I carried out a second study (Study 2) to investigate how ecology-centered experiences contribute to adolescents' environmental attitudes and behaviors in light of other contextual factors, namely environmental responsibility support, ecological thought, age and gender. Study 2 addressed three research questions. First, does ecological thought---a pattern of thought that privileges the relationship between living things---predict environmental attitudes and behaviors (EAB)? Results showed ecological thought did not predict EAB, an important finding considering the latent assumptions of previous research about the relationship between these two factors (e.g., Brugger, Kaiser, & Roczen, 2011). Second, do two types of contextual support, ecology-centered experiences (i.e., experiences with

Commonness and ecology, but not bigger brains, predict urban living in birds.

PubMed

Dale, Svein; Lifjeld, Jan T; Rowe, Melissah

2015-04-11

Several life history and ecological variables have been reported to affect the likelihood of species becoming urbanized. Recently, studies have also focused on the role of brain size in explaining ability to adapt to urban environments. In contrast, however, little is known about the effect of colonization pressure from surrounding areas, which may confound conclusions about what makes a species urban. We recorded presence/absence data for birds in 93 urban sites in Oslo (Norway) and compared these with species lists generated from 137 forest and 51 farmland sites surrounding Oslo which may represent source populations for colonization. We found that the frequency (proportion of sites where present) of a species within the city was strongly and positively associated with its frequency in sites surrounding the city, as were both species breeding habitat and nest site location. In contrast, there were generally no significant effects of relative brain mass or migration on urban occupancy. Furthermore, analyses of previously published data showed that urban density of birds in six other European cities was also positively and significantly associated with density in areas outside cities, whereas relative brain mass showed no such relationship. These results suggest that urban bird communities are primarily determined by how frequently species occurred in the surrounding landscapes and by features of ecology (i.e. breeding habitat and nest site location), whereas species' relative brain mass had no significant effects.

A Social-Ecological, Process-Oriented Perspective on Political Violence and Child Development.

PubMed

Cummings, E Mark; Goeke-Morey, Marcie; Merrilees, Christine E; Taylor, Laura K; Shirlow, Peter A

2014-06-01

Youths' risk for adjustment problems in contexts of political violence is well-documented. However, outcomes vary widely, with many children functioning well. Accordingly, moving beyond further documenting the risk for many negative outcomes associated with living in contexts of political violence, a second generation of research is moving towards identifying the mechanisms and conditions that contribute to children's adjustment. Increasing support is emerging for understanding effects on children in terms of changes in the social contexts in which children live, and in the psychological processes engaged by these social ecologies. Selected themes are considered, including (a) the need to study multiple levels of the social ecology, (b) differentiating between the effects of exposure to contexts of political versus non-political violence, and (c) theories about explanatory processes. Selected research pertinent to these directions is reviewed, including findings from a six-wave longitudinal study on political violence and children in Northern Ireland.

Latin American scientific contribution to ecology.

PubMed

Wojciechowski, Juliana; Ceschin, Fernanda; Pereto, Suelen C A S; Ribas, Luiz G S; Bezerra, Luis A V; Dittrich, Jaqueline; Siqueira, Tadeu; Padial, André A

2017-01-01

Latin America embodies countries of special interest for ecological studies, given that areas with great value for biodiversity are located within their territories. This highlights the importance of an evaluation of ecological research in the Latin America region. We assessed the scientific participation of Latin American researchers in ecological journals, patterns of international collaboration, and defined the main characteristics of the articles. Although Latin American publications have increased in fourteen years, they accounted up to 9% of publications in Ecology. Brazil leaded the scientific production in Latin America, followed by Argentina and Mexico. In general, Latin American articles represented a low percentage of most journals total publication, with particularly low expression in high impact-factor journals. A half of the Latin American publications had international collaboration. Articles with more than five authors and with international collaboration were the most cited. Descriptive studies, mainly based in old theories, are still majority, suggesting that Ecology is in a developing stage in Latin America.

Ecological validity of the screening module and the Daily Living tests of the Neuropsychological Assessment Battery using the Mayo-Portland Adaptability Inventory-4 in postacute brain injury rehabilitation.

PubMed

Zgaljardic, Dennis J; Yancy, Sybil; Temple, Richard O; Watford, Monica F; Miller, Rebekah

2011-11-01

The assessment of ecological validity of neuropsychological measures is an area of growing interest, particularly in the postacute brain injury rehabilitation (PABIR) setting, as there is an increasing demand for clinicians to address functional and real-world outcomes. In the current study, we assessed the predictive value of the Screening module and the Daily Living tests of the Neuropsychological Assessment Battery (NAB) using clinician ratings from the Mayo-Portland Adaptability Inventory-4 (MPAI-4) in patients with moderate to severe traumatic brain injury. Forty-seven individuals were each administered the NAB Screening module (NAB-SM) and the NAB Daily Living (NAB-DL) tests following admission to a residential PABIR program. MPAI-4 ratings were also obtained at admission. Linear regression analysis was used to examine the association between these functional and neuropsychological assessment measures. We replicated prior work (Temple at al., 2009) and expanded evidence for the ecological validity of the NAB-SM. Furthermore, our findings support the ecological validity of the NAB-DL Bill Payment, Judgment, and Map Reading tests with regards to functional skills and real-world activities. The current study supports prior work from our lab assessing the predictive value of the NAB-SM, as well as provides evidence for the ecological validity for select NAB-DL tests in patients with moderate to severe traumatic brain injury admitted to a residential PABIR program.

Effect of a submaximal half-squats warm-up program on vertical jumping ability.

PubMed

Gourgoulis, Vassilios; Aggeloussis, Nickos; Kasimatis, Panagiotis; Mavromatis, Giorgos; Garas, Athanasios

2003-05-01

The purpose of the current research was to study the effect of a warm-up program including submaximal half-squats on vertical jumping ability. Twenty physically active men participated in the study. Each subject performed 5 sets of half-squats with 2 repetitions at each of the following intensities: 20, 40, 60, 80, and 90% of the 1 repetition maximum (1RM) load. Prior to the first set and immediately after the end of the last set, the subjects performed 2 countermovement jumps on a Kistler force platform; the primary goal was to jump as high as possible. The results showed that mean vertical jumping ability improved by 2.39% after the warm-up period. Subjects were then divided into 2 groups according to their 1RM values for the half-squat. Subjects with greater maximal strength ability improved their vertical jumping ability (4.01%) more than did subjects with lower maximal strength (0.42%). A warm-up protocol including half-squats with submaximal loads and explosive execution can be used for short-term improvements of vertical jumping performance, and this effect is greater in athletes with a relatively high strength ability.

Are stepfathers' education levels associated with the intelligence of their stepsons? A register-based study of Norwegian half-brothers.

PubMed

Eriksen, Willy; Sundet, Jon M; Tambs, Kristian

2013-05-01

We examined the relationship between the parents' education levels and the adult intelligence of their children in a population-based, nationwide sample of Norwegian half-brothers with different fathers (2,016 pairs of half-brothers). In a family where the mother has two children with different men, the firstborn child usually lives with the younger child's father during a period of their childhood. This makes it possible to study the non-genetic effects of paternal education on children's development. Results showed that the education level of the younger half-brother's father was positively associated with the intelligence score of the older half-brother. The education level of the older half-brother's father was not associated with the intelligence score of the younger half-brother. Firstborn men whose half-brothers' fathers had high levels of education had intelligence scores that were 33% (95% confidence interval: 18-47%) of a standard deviation higher than those of firstborn men whose half-brothers' fathers had low levels of education, after adjustment for the biological fathers' education levels, mothers' education levels, and other background factors. These findings are compatible with the hypothesis that a child's family environment exerts an effect on the cognitive abilities of the child that lasts into adulthood. © 2012 The British Psychological Society.

Living in the branches: population dynamics and ecological processes in dendritic networks

USGS Publications Warehouse

Grant, E.H.C.; Lowe, W.H.; Fagan, W.F.

2007-01-01

Spatial structure regulates and modifies processes at several levels of ecological organization (e.g. individual/genetic, population and community) and is thus a key component of complex systems, where knowledge at a small scale can be insufficient for understanding system behaviour at a larger scale. Recent syntheses outline potential applications of network theory to ecological systems, but do not address the implications of physical structure for network dynamics. There is a specific need to examine how dendritic habitat structure, such as that found in stream, hedgerow and cave networks, influences ecological processes. Although dendritic networks are one type of ecological network, they are distinguished by two fundamental characteristics: (1) both the branches and the nodes serve as habitat, and (2) the specific spatial arrangement and hierarchical organization of these elements interacts with a species' movement behaviour to alter patterns of population distribution and abundance, and community interactions. Here, we summarize existing theory relating to ecological dynamics in dendritic networks, review empirical studies examining the population- and community-level consequences of these networks, and suggest future research integrating spatial pattern and processes in dendritic systems.

Spatial variation in the flux of atmospheric deposition and its ecological effects in arid Asia

NASA Astrophysics Data System (ADS)

Jiao, Linlin; Wang, Xunming; Li, Danfeng

2018-06-01

Atmospheric deposition is one of the key land surface processes, and plays important roles in regional ecosystems and global climate change. Previous studies have focused on the magnitude of and the temporal and spatial variations in the flux of atmospheric deposition, and the composition of atmospheric deposition on a local scale. However, there have been no comprehensive studies of atmospheric deposition on a regional scale and its ecological effects in arid Asia. The temporal and spatial patterns, composition of atmospheric deposition, and its potential effects on regional ecosystems in arid Asia are investigated in this study. The results show that the annual deposition flux is high on the Turan Plain, Aral Sea Desert, and Tarim Basin. The seasonal deposition flux also varies remarkably among different regions. The Tarim Basin shows higher deposition flux in both spring and summer, southern Mongolian Plateau has a higher deposition flux in spring, and the deposition flux of Iran Plateau is higher in summer. Multiple sources of elements in deposited particles are identified. Calcium, iron, aluminum, and magnesium are mainly derived from remote regions, while zinc, copper and lead have predominantly anthropogenic sources. Atmospheric deposition can provide abundant nutrients to vegetation and consequently play a role in the succession of regional ecosystems by affecting the structure, function, diversity, and primary production of the vegetation, especially the exotic or short-lived opportunistic species in arid Asia. Nevertheless, there is not much evidence of the ecological effects of atmospheric deposition on the regional and local scale. The present results may help in further understanding the mechanism of atmospheric deposition as well as providing a motivation for the protection of the ecological environment in arid Asia.

Nutritional Ecology and Human Health.

PubMed

Raubenheimer, David; Simpson, Stephen J

2016-07-17

In contrast to the spectacular advances in the first half of the twentieth century with micronutrient-related diseases, human nutrition science has failed to stem the more recent rise of obesity and associated cardiometabolic disease (OACD). This failure has triggered debate on the problems and limitations of the field and what change is needed to address these. We briefly review the two broad historical phases of human nutrition science and then provide an overview of the main problems that have been implicated in the poor progress of the field with solving OACD. We next introduce the field of nutritional ecology and show how its ecological-evolutionary foundations can enrich human nutrition science by providing the theory to help address its limitations. We end by introducing a modeling approach from nutritional ecology, termed nutritional geometry, and demonstrate how it can help to implement ecological and evolutionary theory in human nutrition to provide new direction and to better understand and manage OACD.

Teaching Ecologically-Based Communication Skills to Persons Who Are Developmentally Delayed.

ERIC Educational Resources Information Center

Sousie, Susan P.

The paper offers a framework for the design, implementation, and evaluation of appropriate, effective communication instructional programs for persons who are severely developmentally delayed. The use of an ecological approach that incorporates the instruction of communication skills with that of activities of daily living (ADL) is emphasized.…

SOIL BIOLOGY AND ECOLOGY

EPA Science Inventory

The term "Soil Biology", the study of organism groups living in soil, (plants, lichens, algae, moss, bacteria, fungi, protozoa, nematodes, and arthropods), predates "Soil Ecology", the study of interactions between soil organisms as mediated by the soil physical environment. oil ...

[Effect of ecological civilized homestead construction on schistosomiasis control].

PubMed

Tang, Meng; Jia, Tie-Wu; Wu, Zi-Song; Mao, Ping; Chen, Lin; Li, Han-Gang; Zhong, Bo; Qiu, Dong-Chuan; Yao, Qin; Hu, You-Ping

2012-02-01

To evaluate the effect of Ecological Civilized Homestead Construction on schistosomiasis control. The data of ecological civilized homestead construction and schistosomiasis control were collected and analyzed in Meiwan Village, Shuangqiao Town, Danling County, Sichuan Province from 2004 to 2010. Ecological Civilized Homestead Construction was carried out from 2004 to 2010. Totally 454 bio-gas pools were built. All the farmers used well water. The popularized rates of the household bio-gas pool, sanitary toilet, sewage treatment pool reached 100%. The number of cattle was 4, which decreased by 91.30% compared with that in 2004, and all the cattle were fed in captivity. The schistosome infection rates of populations were 0.26% and 0.30% in 2005 and 2008, respectively, and nobody was infected in other years. The infection rate of cattle was 0 from 2004 to 2010. The awareness rate of knowledge about schistosomiasis control achieved 100% in the population over 6 years old. Most of the farmers could use certain protective measures while they were farming. The effect of ecological civilized homestead construction on schistosomiasis control is remarkable.

New Measurement of the 60Fe Half-Life.

PubMed

Rugel, G; Faestermann, T; Knie, K; Korschinek, G; Poutivtsev, M; Schumann, D; Kivel, N; Günther-Leopold, I; Weinreich, R; Wohlmuther, M

2009-08-14

We have made a new determination of the half-life of the radioactive isotope 60Fe using high precision measurements of the number of 60Fe atoms and their activity in a sample containing over 10(15) 60Fe atoms. Our new value for the half-life of 60Fe is (2.62+/-0.04) x 10(6) yr, significantly above the previously reported value of (1.49+/-0.27) x 10(6) yr. Our new measurement for the lifetime of 60Fe has significant implications for interpretations of galactic nucleosynthesis, for determinations of formation time scales of solids in the early Solar System, and for the interpretation of live 60Fe measurements from supernova-ejecta deposits on Earth.

Historical ecology: past, present and future.

PubMed

Szabó, Péter

2015-11-01

The term 'historical ecology' has been used with various meanings since the first half of the 20th century. Studies labelled as historical ecology have been produced in at least four academic disciplines: history, ecology, geography and anthropology. Although all those involved seem to agree that historical ecology concerns the historical interconnectedness of nature and human culture, this field of study has no unified methodology, specialized institutional background and common publication forums. Knowledge of the development of historical ecology is also limited. As a result, the current multitude of definitions of historical ecology is accompanied by divergent opinions as to where the origins of the field are to be sought. In this review, I follow the development of historical ecology from the 18th century to the present. In the first part, I briefly describe some early examples of historical ecological investigations, followed by a description of the various scientific strands in the 20th century that contributed to the formation of historical ecology. In the second part, I discuss the past five decades of historical ecological investigations in more detail, focusing mostly (but not exclusively) on works that their respective authors identified as historical ecology. I also examine the appearance and interconnectedness of the two main trends (ecological and anthropological) in historical ecological research. In the last part, I attempt to outline the future of historical ecology based on common features in existing research. It appears that at present historical ecology is at a crossroads. With rapidly growing interest in historical ecological research, it may move towards institutionalization or remain an umbrella term. © 2014 The Authors. Biological Reviews © 2014 Cambridge Philosophical Society.

Where the wild things are: informal experience and ecological reasoning.

PubMed

Coley, John D

2012-01-01

Category-based induction requires selective use of different relations to guide inferences; this article examines the development of inferences based on ecological relations among living things. Three hundred and forty-six 6-, 8-, and 10-year-old children from rural, suburban, and urban communities projected novel diseases or insides from one species to an ecologically or taxonomically related species; they were also surveyed about hobbies and activities. Frequency of ecological inferences increased with age and with reports of informal exploration of nature, and decreased with population density. By age 10, children preferred taxonomic inferences for insides and ecological inferences for disease, but this pattern emerged earlier among rural children. These results underscore the importance of context by demonstrating effects of both domain-relevant experience and environment on biological reasoning. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

A Social–Ecological, Process-Oriented Perspective on Political Violence and Child Development

PubMed Central

Cummings, E. Mark; Goeke-Morey, Marcie; Merrilees, Christine E.; Taylor, Laura K.; Shirlow, Peter A.

2015-01-01

Youths’ risk for adjustment problems in contexts of political violence is well-documented. However, outcomes vary widely, with many children functioning well. Accordingly, moving beyond further documenting the risk for many negative outcomes associated with living in contexts of political violence, a second generation of research is moving towards identifying the mechanisms and conditions that contribute to children’s adjustment. Increasing support is emerging for understanding effects on children in terms of changes in the social contexts in which children live, and in the psychological processes engaged by these social ecologies. Selected themes are considered, including (a) the need to study multiple levels of the social ecology, (b) differentiating between the effects of exposure to contexts of political versus non-political violence, and (c) theories about explanatory processes. Selected research pertinent to these directions is reviewed, including findings from a six-wave longitudinal study on political violence and children in Northern Ireland. PMID:26877765

Environmental Education as a Lived-Body Practice? A Contemplative Pedagogy Perspective

ERIC Educational Resources Information Center

Pulkki, Jani; Dahlin, Bo; Varri, Veli-Matti

2017-01-01

Environmental education usually appeals to the students' knowledge and rational understanding. Even though this is needed, there is a neglected aspect of learning ecologically fruitful action; that of the lived-body. This paper introduces the lived-body as an important site for learning ecological action. An argument is made for the need of a…

Ecological Forecasting in the Applied Sciences Program and Input to the Decadal Survey

NASA Technical Reports Server (NTRS)

Skiles, Joseph

2015-01-01

Ecological forecasting uses knowledge of physics, ecology and physiology to predict how ecosystems will change in the future in response to environmental factors. Further, Ecological Forecasting employs observations and models to predict the effects of environmental change on ecosystems. In doing so, it applies information from the physical, biological, and social sciences and promotes a scientific synthesis across the domains of physics, geology, chemistry, biology, and psychology. The goal is reliable forecasts that allow decision makers access to science-based tools in order to project changes in living systems. The next decadal survey will direct the development Earth Observation sensors and satellites for the next ten years. It is important that these new sensors and satellites address the requirements for ecosystem models, imagery, and other data for resource management. This presentation will give examples of these model inputs and some resources needed for NASA to continue effective Ecological Forecasting.

Historical ecology: past, present and future

PubMed Central

Szabó, Péter

2017-01-01

The term ‘historical ecology’ has been used with various meanings since the first half of the 20th century. Studies labelled as historical ecology have been produced in at least four academic disciplines: history, ecology, geography and anthropology. Although all those involved seem to agree that historical ecology concerns the historical interconnectedness of nature and human culture, this field of study has no unified methodology, specialized institutional background and common publication forums. Knowledge of the development of historical ecology is also limited. As a result, the current multitude of definitions of historical ecology is accompanied by divergent opinions as to where the origins of the field are to be sought. In this review, I follow the development of historical ecology from the 18th century to the present. In the first part, I briefly describe some early examples of historical ecological investigations, followed by a description of the various scientific strands in the 20th century that contributed to the formation of historical ecology. In the second part, I discuss the past five decades of historical ecological investigations in more detail, focusing mostly (but not exclusively) on works that their respective authors identified as historical ecology. I also examine the appearance and interconnectedness of the two main trends (ecological and anthropological) in historical ecological research. In the last part, I attempt to outline the future of historical ecology based on common features in existing research. It appears that at present historical ecology is at the crossroads. With rapidly growing interest in historical ecological research, it may move towards institutionalization or remain an umbrella term. PMID:25174685

Quantifying the dilution effect for models in ecological epidemiology.

PubMed

Roberts, M G; Heesterbeek, J A P

2018-03-01

The dilution effect , where an increase in biodiversity results in a reduction in the prevalence of an infectious disease, has been the subject of speculation and controversy. Conversely, an amplification effect occurs when increased biodiversity is related to an increase in prevalence. We explore the conditions under which these effects arise, using multi species compartmental models that integrate ecological and epidemiological interactions. We introduce three potential metrics for quantifying dilution and amplification, one based on infection prevalence in a focal host species, one based on the size of the infected subpopulation of that species and one based on the basic reproduction number. We introduce our approach in the simplest epidemiological setting with two species, and show that the existence and strength of a dilution effect is influenced strongly by the choices made to describe the system and the metric used to gauge the effect. We show that our method can be generalized to any number of species and to more complicated ecological and epidemiological dynamics. Our method allows a rigorous analysis of ecological systems where dilution effects have been postulated, and contributes to future progress in understanding the phenomenon of dilution in the context of infectious disease dynamics and infection risk. © 2018 The Author(s).

Method to Reduce Long-lived Fission Products by Nuclear Transmutations with Fast Spectrum Reactors.

PubMed

Chiba, Satoshi; Wakabayashi, Toshio; Tachi, Yoshiaki; Takaki, Naoyuki; Terashima, Atsunori; Okumura, Shin; Yoshida, Tadashi

2017-10-24

Transmutation of long-lived fission products (LLFPs: 79 Se, 93 Zr, 99 Tc, 107 Pd, 129 I, and 135 Cs) into short-lived or non-radioactive nuclides by fast neutron spectrum reactors without isotope separation has been proposed as a solution to the problem of radioactive wastes disposal. Despite investigation of many methods, such transmutation remains technologically difficult. To establish an effective and efficient transmutation system, we propose a novel neutron moderator material, yttrium deuteride (YD 2 ), to soften the neutron spectrum leaking from the reactor core. Neutron energy spectra and effective half-lives of LLFPs, transmutation rates, and support ratios were evaluated with the continuous-energy Monte Carlo code MVP-II/MVP-BURN and the JENDL-4.0 cross section library. With the YD 2 moderator in the radial blanket and shield regions, effective half-lives drastically decreased from 106 to 102 years and the support ratios reached 1.0 for all six LLFPs. This successful development and implementation of a transmutation system for LLFPs without isotope separation contributes to a the ability of fast spectrum reactors to reduce radioactive waste by consuming their own LLFPs.

Effects of polyamine levels on the degradation of short-lived and long-lived proteins in cultured L-132 human lung cells.

PubMed Central

Corella, D; Guillén, M; Hernández, J M; Hernández-Yago, J

1998-01-01

Biogenic polyamines have important regulatory functions in various biological processes and it has also been suggested that they could modulate intracellular protein degradation. For an overall assessment of the role of polyamines in this process, we have investigated the effect that the decrease in intracellular polyamine levels caused by inhibitors of polyamine biosynthesis brings about on the degradation of the pools of short- and long-lived proteins in cultured L-132 human lung cells. Treatment of cells with 100 microM (2R,5R)-delta-methyl acetylenic putrescine (MAP), a potent enzyme-activated irreversible inhibitor of ornithine decarboxylase, or with 100 microM MAP plus 50 microM N-butyl 1,3-diaminopropane, a specific inhibitor of spermine synthase, caused a similar decrease (65-70% of control) in the total intracellular levels of polyamines, although they affected the concentrations of spermidine and spermine differently. The effect of the two treatments on protein degradation was essentially the same. In polyamine-depleted cells we observed an inhibition of degradation in long-lived proteins of 16% (P<0.05), with a significant increase in the half-life (t12) of this pool from 100.5 to 120.1 h. This was concomitant with an increase of 26% (P<0. 05) in degradation in short-lived proteins, with a significant decrease in the t12 of this pool from 0.85 to 0.67 h. Recovery of polyamine levels by the addition of 50 microM spermidine to polyamine-depleted cells resulted in a restoration of the degradation rates in both pools of proteins. The way(s) by which polyamines could modulate proteolysis are discussed. PMID:9716494

Half-life of the electron-capture decay of {sup 97}Ru: Precision measurement shows no temperature dependence

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

Goodwin, J. R.; Golovko, V. V.; Iacob, V. E.

2009-10-15

We have measured the half-life of the electron-capture (ec) decay of {sup 97}Ru in a metallic environment, both at low temperature (19 K), and also at room temperature. We find the half-lives at both temperatures to be the same within 0.1%. This demonstrates that a recent claim that the ec decay half-life for {sup 7}Be changes by 0.9%{+-}0.2% under similar circumstances certainly cannot be generalized to other ec decays. Our results for the half-life of {sup 97}Ru, 2.8370(14) d at room temperature and 2.8382(14) d at 19 K, are consistent with, but much more precise than, previous room-temperature measurements. Inmore » addition, we have also measured the half-lives of the {beta}{sup -}-emitters {sup 103}Ru and {sup 105}Rh at both temperatures, and found them also to be unchanged.« less

Ecology of Problem Individuals and the Efficacy of Selective Wildlife Management.

PubMed

Swan, George J F; Redpath, Steve M; Bearhop, Stuart; McDonald, Robbie A

2017-07-01

As a result of ecological and social drivers, the management of problems caused by wildlife is becoming more selective, often targeting specific animals. Narrowing the sights of management relies upon the ecology of certain 'problem individuals' and their disproportionate contribution to impacts upon human interests. We assess the ecological evidence for problem individuals and confirm that some individuals or classes can be both disproportionately responsible and more likely to reoffend. The benefits of management can sometimes be short-lived, and selective management can affect tolerance of wildlife for better or worse, but, when effectively targeted, selective management can bring benefits by mitigating impact and conflict, often in a more socially acceptable way. Copyright © 2017 Elsevier Ltd. All rights reserved.

An ecological assessment of pasturelands in the Balkhash area of Kazakhstan with remote sensing and models

NASA Astrophysics Data System (ADS)

Lebed, L.; Qi, J.; Heilman, P.

2012-06-01

The 187 million hectares of pasturelands in Kazakhstan play a key role in the nation’s economy, as livestock production accounted for 54% of total agricultural production in 2010. However, more than half of these lands have been degraded as a result of unregulated grazing practices. Therefore, effective long term ecological monitoring of pasturelands in Kazakhstan is imperative to ensure sustainable pastureland management. As a case study in this research, we demonstrated how the ecological conditions could be assessed with remote sensing technologies and pastureland models. The example focuses on the southern Balkhash area with study sites on a foothill plain with Artemisia-ephemeral plants and a sandy plain with psammophilic vegetation in the Turan Desert. The assessment was based on remotely sensed imagery and meteorological data, a geobotanical archive and periodic ground sampling. The Pasture agrometeorological model was used to calculate biological, ecological and economic indicators to assess pastureland condition. The results showed that field surveys, meteorological observations, remote sensing and ecological models, such as Pasture, could be combined to effectively assess the ecological conditions of pasturelands and provide information about forage production that is critically important for balancing grazing and ecological conservation.

Examining acute bi-directional relationships between affect, physical feeling states, and physical activity in free-living situations using electronic ecological momentary assessment.

PubMed

Liao, Yue; Chou, Chih-Ping; Huh, Jimi; Leventhal, Adam; Dunton, Genevieve

2017-06-01

Current knowledge about the relationship of physical activity with acute affective and physical feeling states is informed largely by lab-based studies, which have limited generalizability to the natural ecology. This study used ecological momentary assessment to assess subjective affective and physical feeling states in free-living settings across 4 days from 110 non-physically active adults (Age M = 40.4, SD = 9.7). Light physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) were measured objectively by an accelerometer. Multilevel modeling was used to test the bi-directional associations between affective and physical feeling states and LPA/MVPA minutes. Higher positive affect, lower negative affect and fatigue were associated with more MVPA over the subsequent 15 min, while higher negative affect and energy were associated with more LPA over the subsequent 15 and 30 min. Additionally, more LPA and MVPA were associated with feeling more energetic over the subsequent 15 and 30 min, and more LPA was additionally associated with feeling more negative and less tired over the subsequent 15 and 30 min. Positive and negative affective states might serve as antecedents to but not consequences of MVPA in adults' daily lives. Changes in LPA may be predicted and followed by negative affective states. Physical feeling states appear to lead up to and follow changes in both LPA and MVPA.

A half-metallic half-Heusler alloy having the largest atomic-like magnetic moment at optimized lattice constant

DOE PAGES

Zhang, R. L.; Damewood, L.; Fong, C. Y.; ...

2016-11-02

For half-Heusler alloys, the general formula is XYZ, where X can be a transition or alkali metal element, Y is another transition metal element, typically Mn or Cr, and Z is a group IV element or a pnicitide. The atomic arrangements within a unit-cell show three configurations. Before this study, most of the predictions of half-metallic properties of half-Heusler alloys at the lattice constants differing from their optimized lattice constant. Based on the electropositivity of X and electronegativity of Z for half-Heusler alloys, we found that one of the configurations of LiCrS exhibits half-metallic properties at its optimized lattice constantmore » of 5.803Å, and has the maximum atomic-like magnetic moment of 5μ B. In conclusion, the challenges of its growth and the effects of the spin-orbit effect in this alloy will be discussed.« less

Rhodolith holobionts in a changing ocean: Ocean Acidification effects on the free-living coralline algae and their associated microbiota

NASA Astrophysics Data System (ADS)

Cavalcanti, G.

2016-02-01

Rhodoliths, free-living coralline algae (Rhodophyta, Corallinales), form extensive beds worldwide distributed, ecologically important for the functioning of marine environments. Rhodolith beds are large carbon sinks, but the growth of the Rhodolith holobiont might be affected by changes in ocean carbonate chemistry, predicted to occur in the near future. The term holobiont refers to any organism and all of its associated symbiotic microbes (parasites, mutualists, synergists and amensals), including endobionts and epibionts that perform diverse ecological roles. A holobiont occupies and adapts to an ecological niche, and is able to employ strategies unavailable in any one species alone when challenged by environmental perturbations. The impact of increasing acidification of oceans on Rhodolith holobiont growth might be due to dissolution of their calcium carbonated skeleton, effects over photosynthetic rates, as well as changes in their associated microbial community, herein investigated through physiological assays (photosynthesis) and metagenomics (WGS Illumina sequencing). We used a mesocosm experimental system to assess potential effects of OA on dead and live rhodoliths following a 5 week exposure to increased pCO2. Integrating both taxonomical and functional diversity from multiple players (Eukarya, Bacteria and Archaea) in the acidification context, we have demonstrated that the Rhodolith holobiont harbor an impressive stable microbiome, whereas high pCO2 affect the seawater microbes. Our study has extended the comprehension of physiological relationships within Rhodolith holobiont by including the microbial component in the response of this coralline algae to higher pCO2 levels, and endorsed previous works that indicated a parabolic photosynthetic response to pH and pCO2. The outcomes of this research are an increased understanding of microbes associated with Rhodoliths and additional hints on how the holobiont might thrive in face to global climate changes.

The Family: A School for Living

ERIC Educational Resources Information Center

Garbarino, James

1976-01-01

In the face of so many trends toward fragmentation, overspecialization, and instrumentally impersonal relationships in the day-to-day lives of families, the cause of social habitability is best served when we are able to see clearly the ecology of human development: families as schools for living and schools as families. (Author)

What is dental ecology?

PubMed

Cuozzo, Frank P; Sauther, Michelle L

2012-06-01

Teeth have long been used as indicators of primate ecology. Early work focused on the links between dental morphology, diet, and behavior, with more recent years emphasizing dental wear, microstructure, development, and biogeochemistry, to understand primate ecology. Our study of Lemur catta at the Beza Mahafaly Special Reserve, Madagascar, has revealed an unusual pattern of severe tooth wear and frequent tooth loss, primarily the result of consuming a fallback food for which these primates are not dentally adapted. Interpreting these data was only possible by combining our areas of expertise (dental anatomy [FC] and primate ecology [MS]). By integrating theoretical, methodological, and applied aspects of both areas of research, we adopted the term "dental ecology"-defined as the broad study of how teeth respond to the environment. Specifically, we view dental ecology as an interpretive framework using teeth as a vehicle for understanding an organism's ecology, which builds upon earlier work, but creates a new synthesis of anatomy and ecology that is only possible with detailed knowledge of living primates. This framework includes (1) identifying patterns of dental pathology and tooth use-wear, within the context of feeding ecology, behavior, habitat variation, and anthropogenic change, (2) assessing ways in which dental development and biogeochemical signals can reflect habitat, environmental change and/or stress, and (3) how dental microstructure and macro-morphology are adapted to, and reflect feeding ecology. Here we define dental ecology, provide a short summary of the development of this perspective, and place our new work into this context. Copyright © 2012 Wiley Periodicals, Inc.

[Effects of biochar on microbial ecology in agriculture soil: a review].

PubMed

Ding, Yan-Li; Liu, Jie; Wang, Ying-Ying

2013-11-01

Biochar, as a new type of soil amendment, has been obtained considerable attention in the research field of environmental sciences worldwide. The studies on the effects of biochar in improving soil physical and chemical properties started quite earlier, and already covered the field of soil microbial ecology. However, most of the studies considered the soil physical and chemical properties and the microbial ecology separately, with less consideration of their interactions. This paper summarized and analyzed the interrelationships between the changes of soil physical and chemical properties and of soil microbial community after the addition of biochar. Biochar can not only improve soil pH value, strengthen soil water-holding capacity, increase soil organic matter content, but also affect soil microbial community structure, and alter the abundance of soil bacteria and fungi. After the addition of biochar, the soil environment and soil microorganisms are interacted each other, and promote the improvement of soil microbial ecological system together. This review was to provide a novel perspective for the in-depth studies of the effects of biochar on soil microbial ecology, and to promote the researches on the beneficial effects of biochar to the environment from ecological aspect. The methods to improve the effectiveness of biochar application were discussed, and the potential applications of biochar in soil bioremediation were further analyzed.

Living alongside railway tracks: Long-term effects of nocturnal noise on sleep and cardiovascular reactivity as a function of age.

PubMed

Tassi, Patricia; Rohmer, Odile; Schimchowitsch, Sarah; Eschenlauer, Arnaud; Bonnefond, Anne; Margiocchi, Florence; Poisson, Franck; Muzet, Alain

2010-10-01

Very few studies were devoted to permanent effects of nocturnal railway noise on sleep and cardiovascular reactivity. We investigated the effects of nocturnal railway noise on sleep and cardiovascular response in young and middle-aged adults living for many years either near a railway track or in a quiet area. Forty subjects (50% males) divided into two age groups (juniors: 26.2+/-3.6 and seniors: 56.2+/-4.2) participated in this experiment. Half of them lived near a railway track (RW group: 2.6 to 19 years) and the other half in a quiet environment (QE group: 8.1 to 14.2 years). After an adaptation night, all subjects underwent two nights in the laboratory: one control night and one noisy night (30 by-passes of a freight train). Sleep and cardiovascular modifications were assessed in response to noise. Sleep fragmentation indices were lower in RW subjects compared to QE whatever their age. In response to noise, there was a higher cardiovascular response rate to noise in RW juniors and a lower cardiovascular response rate in RW seniors compared to their age-paired QE counterparts. In conclusion, permanent exposure to nocturnal railway noise leads to decreased sleep fragmentation and to cardiovascular habituation. It is suggested that during the initial period experienced by residents living near railway tracks, nocturnal railway noise could induce a sensitization process on the autonomic response to noise reflecting a startle/defense reflex due to its functional significance, which progressively turns to habituation in the long-term if no adverse effect is experienced. Copyright 2010 Elsevier Ltd. All rights reserved.

Nuclear Decay Data for the International Reactor Dosimetry Library for Fission and Fusion (IRDFF): Updated Evaluations of the Half-Lives and Gamma Ray Intensities

NASA Astrophysics Data System (ADS)

Chechev, Valery P.; Kuzmenko, Nikolay K.

2016-02-01

Updated evaluations of the half-lives and prominent gamma ray intensities have been presented for 20 radionuclides - dosimetry reaction residuals. The new values of these decay characteristics recommended for the IRDFF library were obtained using the approaches and methodology adopted by the working group of the Decay Data Evaluation Project (DDEP) cooperation. The experimental data published up to 2014 were taken into account in updated evaluations. The list of radionuclides includes 3H, 18F, 22Na, 24Na, 46Sc, 51Cr, 54Mn, 59Fe, 57Co, 60Co, 57Ni, 64Cu, 88Y, 132Te, 131I, 140Ba, 140La, 141Ce, 182Ta, 198Au.

Genome-wide gene expression and RNA half-life measurements allow predictions of regulation and metabolic behavior in Methanosarcina acetivorans

DOE PAGES

Peterson, Joseph R.; Thor, ShengShee; Kohler, Lars; ...

2016-11-16

Here, while a few studies on the variations in mRNA expression and half-lives measured under different growth conditions have been used to predict patterns of regulation in bacterial organisms, the extent to which this information can also play a role in defining metabolic phenotypes has yet to be examined systematically. Here we present the first comprehensive study for a model methanogen. As a result, we use expression and half-life data for the methanogen Methanosarcina acetivorans growing on fast- and slow-growth substrates to examine the regulation of its genes. Unlike Escherichia coli where only small shifts in half-lives were observed, wemore » found that most mRNA have significantly longer half-lives for slow growth on acetate compared to fast growth on methanol or trimethylamine. Interestingly, half-life shifts are not uniform across functional classes of enzymes, suggesting the existence of a selective stabilization mechanism for mRNAs. Using the transcriptomics data we determined whether transcription or degradation rate controls the change in transcript abundance. Degradation was found to control abundance for about half of the metabolic genes underscoring its role in regulating metabolism. Genes involved in half of the metabolic reactions were found to be differentially expressed among the substrates suggesting the existence of drastically different metabolic phenotypes that extend beyond just the methanogenesis pathways. By integrating expression data with an updated metabolic model of the organism (iST807) significant differences in pathway flux and production of metabolites were predicted for the three growth substrates. In conclusion, this study provides the first global picture of differential expression and half-lives for a class II methanogen, as well as provides the first evidence in a single organism that drastic genome-wide shifts in RNA half-lives can be modulated by growth substrate. We determined which genes in each metabolic pathway

Genome-wide gene expression and RNA half-life measurements allow predictions of regulation and metabolic behavior in Methanosarcina acetivorans

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

Peterson, Joseph R.; Thor, ShengShee; Kohler, Lars

Here, while a few studies on the variations in mRNA expression and half-lives measured under different growth conditions have been used to predict patterns of regulation in bacterial organisms, the extent to which this information can also play a role in defining metabolic phenotypes has yet to be examined systematically. Here we present the first comprehensive study for a model methanogen. As a result, we use expression and half-life data for the methanogen Methanosarcina acetivorans growing on fast- and slow-growth substrates to examine the regulation of its genes. Unlike Escherichia coli where only small shifts in half-lives were observed, wemore » found that most mRNA have significantly longer half-lives for slow growth on acetate compared to fast growth on methanol or trimethylamine. Interestingly, half-life shifts are not uniform across functional classes of enzymes, suggesting the existence of a selective stabilization mechanism for mRNAs. Using the transcriptomics data we determined whether transcription or degradation rate controls the change in transcript abundance. Degradation was found to control abundance for about half of the metabolic genes underscoring its role in regulating metabolism. Genes involved in half of the metabolic reactions were found to be differentially expressed among the substrates suggesting the existence of drastically different metabolic phenotypes that extend beyond just the methanogenesis pathways. By integrating expression data with an updated metabolic model of the organism (iST807) significant differences in pathway flux and production of metabolites were predicted for the three growth substrates. In conclusion, this study provides the first global picture of differential expression and half-lives for a class II methanogen, as well as provides the first evidence in a single organism that drastic genome-wide shifts in RNA half-lives can be modulated by growth substrate. We determined which genes in each metabolic pathway

Rural Active Living: A Call to Action.

PubMed

Umstattd Meyer, M Renée; Moore, Justin B; Abildso, Christiaan; Edwards, Michael B; Gamble, Abigail; Baskin, Monica L

2016-01-01

Rural residents are less physically active than their urban counterparts and disproportionately affected by chronic diseases and conditions associated with insufficient activity. While the ecological model has been successful in promoting and translating active living research in urban settings, relatively little research has been conducted in rural settings. The resulting research gap prohibits a comprehensive understanding and application of solutions for active living in rural America. Therefore, the purpose of this article was to assess the evidence base for an ecological model of active living for rural populations and outline key scientific gaps that inhibit the development and application of solutions. Specifically, we reexamined the 4 domains conceptualized by the model and suggest that there is a dearth of research specific to rural communities across all areas of the framework. Considering the limited rural-specific efforts, we propose areas that need addressing to mobilize rural active living researchers and practitioners into action.

Rural Active Living: A Call to Action

PubMed Central

Meyer, M. Renée Umstattd; Moore, Justin B.; Abildso, Christiaan; Edwards, Michael B.; Gamble, Abigail; Baskin, Monica L.

2015-01-01

Rural residents are less physically active than their urban counterparts and disproportionately affected by chronic diseases and conditions associated with insufficient activity. While the ecological model has been successful in promoting and translating active living research in urban settings, relatively little research has been conducted in rural settings. The resulting research gap prohibits a comprehensive understanding and application of solutions for active living in rural America. Therefore, the purpose of this paper was to assess the evidence-base for an ecological model of active living for rural populations and outline key scientific gaps that inhibit the development and application of solutions. Specifically, we reexamined the four domains conceptualized by the model and suggest there is a dearth of research specific to rural communities across all areas of the framework. Considering the limited rural-specific efforts, we propose areas that need addressing in order to mobilize rural active living researchers and practitioners into action. PMID:26327514

BOOK REVIEW OF "ECOLOGICAL EFFECTS OF ROADS"

EPA Science Inventory

Throughout the world, roads have become a permanent part of our environment. The ecological effects of roads and traffic are as consequential as other topical issues such as losses in biological diversity and damage by exotic and invasive species. However, this issue has usuall...

Physiological, anatomical, and ecological characteristics of southern live oak

Treesearch

Yadong Qi; Jammie Favorite; Kit L. Chin; Ying Xiao

2006-01-01

Gas exchanges of sun-exposed and shaded leaves of southern live oak (Quercus virginiana Mill.) were studied monthly from May to September, 2000. Six healthy live oak trees with d.b.h. ranging from 21 to 148 cm on Southern University’s campus in Baton Rouge, LA, were selected for the study. Instantaneous gas exchanges were measured during clear sky...

Static and dynamic half-life and lifetime molecular turnover of enzymes.

PubMed

Miyawaki, Osato; Kanazawa, Tsukasa; Maruyama, Chika; Dozen, Michiko

2017-01-01

The static half-life of an enzyme is the half-life of a free enzyme not working without substrate and the dynamic half-life is that of an active enzyme working with plenty amount of substrate. These two half-lives were measured and compared for glucoamylase (GA) and β-galactosidase (BG). The dynamic half-life was much longer than the static half-life by one to three orders of magnitude for both enzymes. For BG, the half-life of the enzyme physically entrapped in a membrane reactor was also measured. In this case also, the half-life of BG in the membrane reactor was much longer than the free enzyme without substrate. These results suggest the large difference in stabilities between the free enzyme and the enzyme-substrate complex. This may be related to the natural enzyme metabolism. According to the difference in half-life, the lifetime molecular turnover (LMT), which is the number of product molecules produced by a single molecule of enzyme until it loses its activity completely, was much higher by one to four orders of magnitude for the active enzyme than the free enzyme. The concept of LMT, proposed here, will be important in bioreactor operations with or without immobilization. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Effective Exercises in Teaching Landscape Ecology

Treesearch

Scott M. Pearson; Monica G. Turner; Dean L. Urban

1999-01-01

The development of landscape ecology and its many applications to land management created a need for courses that address both the conceptual and practical sides of the discipline. Graduate seminars and full-fledged courses in landscape ecology are now featured at many colleges and universities; undergraduate ecology courses may include an introduction to principles...

Effects of urbanization expansion on landscape pattern and region ecological risk in Chinese coastal city: a case study of Yantai city.

PubMed

Zhou, Di; Shi, Ping; Wu, Xiaoqing; Ma, Jinwei; Yu, Junbao

2014-01-01

Applied with remote sensing, GIS, and mathematical statistics, the spatial-temporal evolution characteristics of urbanization expansion of Yantai city from 1974 to 2009 was studied. Based on landscape pattern metrics and ecological risk index, the landscape ecological risk from the landscape pattern dynamics was evaluated. The results showed that the area of urban land increased by 189.77 km(2) with average expansion area of 5.42 km(2) y(-1) from 1974 to 2009. The urbanization intensity index during 2004-2009 was 3.92 times of that during 1974-1990. The land use types of urban land and farmland changed greatly. The changes of landscape pattern metrics for land use patterns indicated that the intensity of human activities had strengthened gradually in study period. The landscape ecological risk pattern of Yantai city shaped half-round rings along the coastline. The ecological risk index decreased with increase of the distance to the coastline. The ratio of high ecological risk to subhigh ecological risk zones in 2009 was 2.23 times of that in 1990. The significant linear relationship of urbanization intensity index and regional ecological risk indicated that the anthropological economic activities were decisive factors for sustainable development of costal ecological environment.

Effects of Urbanization Expansion on Landscape Pattern and Region Ecological Risk in Chinese Coastal City: A Case Study of Yantai City

NASA Astrophysics Data System (ADS)

Zhou, D.; Yu, J.; Li, Y.; Zhan, C.

2017-12-01

Applied with remote sensing, GIS, and mathematical statistics, the spatial-temporal evolution characteristics of urbanization expansion of Yantai city from1974 to 2009 was studied. Based on landscape pattern metrics and ecological risk index, the landscape ecological risk from the landscape pattern dynamics was evaluated. The results showed that the area of urban land increased by 189.77 km2 with average expansion area of 5.42 km2 y-1 from1974 to 2009.The urbanization intensity index during 2004-2009 was 3.92 times of that during 1974-1990. The land use types of urban land and farmland changed greatly. The changes of landscape pattern metrics for land use patterns indicated that the intensity of human activities had strengthened gradually in study period. The landscape ecological risk pattern of Yantai city shaped half-round rings along the coastline. The ecological risk index decreased with increase of the distance to the coastline. The ratio of high ecological risk to sub-high ecological risk zones in 2009 was 2.23 times of that in 1990.The significant linear relationship of urbanization intensity index and regional ecological risk indicated that the anthropological economic activities were decisive factors for sustainable development of costal ecological environment.

Effects of Urbanization Expansion on Landscape Pattern and Region Ecological Risk in Chinese Coastal City: A Case Study of Yantai City

PubMed Central

Zhou, Di; Shi, Ping; Wu, Xiaoqing; Ma, Jinwei

2014-01-01

Applied with remote sensing, GIS, and mathematical statistics, the spatial-temporal evolution characteristics of urbanization expansion of Yantai city from 1974 to 2009 was studied. Based on landscape pattern metrics and ecological risk index, the landscape ecological risk from the landscape pattern dynamics was evaluated. The results showed that the area of urban land increased by 189.77 km2 with average expansion area of 5.42 km2 y−1 from 1974 to 2009. The urbanization intensity index during 2004–2009 was 3.92 times of that during 1974–1990. The land use types of urban land and farmland changed greatly. The changes of landscape pattern metrics for land use patterns indicated that the intensity of human activities had strengthened gradually in study period. The landscape ecological risk pattern of Yantai city shaped half-round rings along the coastline. The ecological risk index decreased with increase of the distance to the coastline. The ratio of high ecological risk to subhigh ecological risk zones in 2009 was 2.23 times of that in 1990. The significant linear relationship of urbanization intensity index and regional ecological risk indicated that the anthropological economic activities were decisive factors for sustainable development of costal ecological environment. PMID:24983003

Parasites, info-disruption, and the ecology of fear.

PubMed

Rohr, Jason R; Swan, Autumn; Raffel, Thomas R; Hudson, Peter J

2009-03-01

There is growing interest in the ecological consequences of fear, as evidenced by the numerous studies on the nonconsumptive, trait-mediated effects of predators. Parasitism, however, has yet to be fully integrated into research on the ecology of fear, despite it having direct negative and often lethal effects on hosts and being the most common life history strategy on the planet. This might at least be partly due to the traditional, but untested, assumption that anti-parasite responses are weak relative to anti-predator responses. To test this hypothesis, we quantified the activity and location responses of Bufo americanus tadpoles to one of six chemical cues: water; cercariae of Echinostoma trivolvis, a trematode which infects and can kill amphibians; a snail releasing E. trivolvis cercariae; an uninfected snail; food; or conspecific alarm chemicals signaling predation. There is also literature encouraging research on the context dependency and pollution-induced disruption of fear responses. Consequently, before quantifying responses to the chemical cues, half of the B. americanus were exposed to the herbicide atrazine (201 microg/l for 4 days), a reported inhibitor of fear responses in fish. Tadpoles were attracted to food, were indifferent to an uninfected snail, avoided alarm chemicals, and exhibited avoidance and elevated activity in response to a snail shedding cercariae and cercariae alone. Atrazine had no detectable effects on B. americanus' responses to the tested cues despite the use of a higher concentration and longer exposure duration than has been repeatedly shown to inhibit chemical cue detection in fish. The magnitude of anti-parasite and anti-predator responses were qualitatively similar, suggesting that the fear of disease and its ecological consequences could be comparable to that of predation. Consequently, we call for a greater integration of parasites into research on the ecology of fear and trait-mediated indirect effects.

Dissipation, half-lives, and mass spectrometric identification of chlorpyrifos and its two metabolites on field-grown collard and kale.

PubMed

Antonious, George F; Turley, Eric T; Abubakari, Mutari; Snyder, John C

2017-04-03

The persistence and fate of chlorpyrifos and its two metabolites, chlorpyrifos-oxon and the 3, 5, 6-trichloro-2-pyridinol (TCP) break-down product were investigated on kale and collard leaves under field conditions. A simultaneous extraction and quantification procedure was developed for chrorpyrifos and its two main metabolites. Residues of chlorpyrifos, chlorpyrifos oxon, and TCP were determined using a gas chromatograph (GC) equipped with an electron capture detector (GC/ECD). Chlorpyrifos metabolites were detectable up to 23 days following application. Residues were confirmed using a GC equipped with a mass selective detector (GC/MSD) in total ion mode. Initial residues of chlorpyrifos were greater on collard (14.5 µg g -1 ) than kale (8.2 µg g -1 ) corresponding to half-lives (T 1/2 ) values of 7.4 and 2.2 days, respectively. TCP, the hydrolysis product, was more persistent on collards with an estimated T 1/2 of 6.5 days compared to kale (T 1/2 of 1.9 days).

Half-and-Half Palatoplasty.

PubMed

Han, Hyun Ho; Kang, In Sook; Rhie, Jong Won

2014-08-01

A 14-month-old child was diagnosed with a Veau Class II cleft palate. Von Langenbeck palatoplasty was performed for the right palate, and V-Y pushback palatoplasty was performed for the left palate. The child did not have a special problem during the surgery, and the authors were able to elongate the cleft by 10 mm. Contrary to preoperative concerns regarding the hybrid use of palatoplasties, the uvula and midline incisions remained balanced in the middle. The authors named this combination method "half-and-half palatoplasty" and plan to conduct a long-term follow up study as a potential solution that minimizes the complications of palatoplasty.

Half-and-Half Palatoplasty

PubMed Central

Han, Hyun Ho; Kang, In Sook

2014-01-01

A 14-month-old child was diagnosed with a Veau Class II cleft palate. Von Langenbeck palatoplasty was performed for the right palate, and V-Y pushback palatoplasty was performed for the left palate. The child did not have a special problem during the surgery, and the authors were able to elongate the cleft by 10 mm. Contrary to preoperative concerns regarding the hybrid use of palatoplasties, the uvula and midline incisions remained balanced in the middle. The authors named this combination method "half-and-half palatoplasty" and plan to conduct a long-term follow up study as a potential solution that minimizes the complications of palatoplasty. PMID:28913201

Flow effects on benthic stream invertebrates and ecological processes

NASA Astrophysics Data System (ADS)

Koprivsek, Maja; Brilly, Mitja

2010-05-01

Flow is the main abiotic factor in the streams. Flow affects the organisms in many direct and indirect ways. The organisms are directly affected by various hydrodynamic forces and mass transfer processes like drag forces, drift, shear stress, food and gases supply and washing metabolites away. Indirect effects on the organisms are determining and distribution of the particle size and structure of the substrate and determining the morphology of riverbeds. Flow does not affect only on individual organism, but also on many ecological effects. To expose just the most important: dispersal of the organisms, habitat use, resource acquisition, competition and predator-prey interactions. Stream invertebrates are adapted to the various flow conditions in many kinds of way. Some of them are avoiding the high flow with living in a hyporeic zone, while the others are adapted to flow with physical adaptations (the way of feeding, respiration, osmoregulation and resistance to draught), morphological adaptations (dorsoventrally flattened shape of organism, streamlined shape of organism, heterogeneous suckers, silk, claws, swimming hair, bristles and ballast gravel) or with behaviour. As the flow characteristics in a particular stream vary over a broad range of space and time scales, it is necessary to measure accurately the velocity in places where the organisms are present to determine the actual impact of flow on aquatic organisms. By measuring the mean flow at individual vertical in a single cross-section, we cannot get any information about the velocity situation close to the bottom of the riverbed where the stream invertebrates are living. Just measuring the velocity near the bottom is a major problem, as technologies for measuring the velocity and flow of natural watercourses is not adapted to measure so close to the bottom. New researches in the last two decades has shown that the thickness of laminar border layer of stones in the stream is only a few 100 micrometers, what

Effects of strong interactions in a half-metallic magnet: A determinant quantum Monte Carlo study

DOE PAGES

Jiang, M.; Pickett, W. E.; Scalettar, R. T.

2013-04-03

Understanding the effects of electron-electron interactions in half-metallic magnets (HMs), which have band structures with one gapped spin channel and one metallic channel, poses fundamental theoretical issues as well as having importance for their potential applications. Here we use determinant quantum Monte Carlo to study the impacts of an on-site Hubbard interaction U, finite temperature, and an external (Zeeman) magnetic field on a bilayer tight-binding model which is a half-metal in the absence of interactions, by calculating the spectral density, conductivity, spin polarization of carriers, and local magnetic properties. We quantify the effect of U on the degree of thermalmore » depolarization, and follow relative band shifts and monitor when significant gap states appear, each of which can degrade the HM character. For this model, Zeeman coupling induces, at fixed particle number, two successive transitions: compensated half-metal with spin-down band gap → metallic ferromagnet → saturated ferromagnetic insulator. However, over much of the more relevant parameter regime, the half-metallic properties are rather robust to U.« less

Effective intracellular inhibition of the cAMP-dependent protein kinase by microinjection of a modified form of the specific inhibitor peptide PKi in living fibroblasts.

PubMed

Fernandez, A; Mery, J; Vandromme, M; Basset, M; Cavadore, J C; Lamb, N J

1991-08-01

In order to obtain a peptide retaining its biological activity following microinjection into living cells, we have modified a synthetic peptide [PKi(m)(6-24)], derived from the specific inhibitor protein of the cAMP-dependent protein kinase (A-kinase) in two ways: (1) substitution of the arginine at position 18 for a D-arginine; (2) blockade of the side chain on the C-terminal aspartic acid by a cyclohexyl ester group. In an in vitro assay, PKi(m) has retained a specific inhibitory activity against A-kinase as assessed against six other kinases, with similar efficiency to that of the unmodified PKi(5-24) peptide. Microinjection of PKi(m) into living fibroblasts reveals its capacity to prevent the changes in cell morphology and cytoskeleton induced by drugs which activate endogenous A-kinase, whereas the original PKi peptide failed to do so. This inhibition of A-kinase in vivo by PKi(m) lasts between 4 and 6 h after injection. In light of its effective half-life, this modified peptide opens a route for the use of biologically active peptides in vivo, an approach which has been hampered until now by the exceedingly short half-life of peptides inside living cells. By providing a direct means of inhibiting A-kinase activity for sufficiently long periods to observe effects on cellular functions in living cells, PKi(m) represents a powerful tool in studying the potential role of cAMP-dependent phosphorylation in vivo.

Release of genetically engineered insects: a framework to identify potential ecological effects

PubMed Central

David, Aaron S; Kaser, Joe M; Morey, Amy C; Roth, Alexander M; Andow, David A

2013-01-01

Genetically engineered (GE) insects have the potential to radically change pest management worldwide. With recent approvals of GE insect releases, there is a need for a synthesized framework to evaluate their potential ecological and evolutionary effects. The effects may occur in two phases: a transitory phase when the focal population changes in density, and a steady state phase when it reaches a new, constant density. We review potential effects of a rapid change in insect density related to population outbreaks, biological control, invasive species, and other GE organisms to identify a comprehensive list of potential ecological and evolutionary effects of GE insect releases. We apply this framework to the Anopheles gambiae mosquito – a malaria vector being engineered to suppress the wild mosquito population – to identify effects that may occur during the transitory and steady state phases after release. Our methodology reveals many potential effects in each phase, perhaps most notably those dealing with immunity in the transitory phase, and with pathogen and vector evolution in the steady state phase. Importantly, this framework identifies knowledge gaps in mosquito ecology. Identifying effects in the transitory and steady state phases allows more rigorous identification of the potential ecological effects of GE insect release. PMID:24198955

Evaluation of the 129I Half-Life Value Through Analyses of Primitive Meteorites

NASA Astrophysics Data System (ADS)

Pravdivtseva, Olga; Meshik, Alex; Hohenberg, Charles M.

The preserved record of decay of now-extinct 129I into 129Xe forms the basis of the I-Xe chronometer. Comparison of the high precision I-Xe and Pb-Pb ages of chondrules and pure mineral phases separated from eight meteorites suggests the 17.5 ÷ 14.6 Ma range for the 129I half-life, assuming that the 235U and 238U half-lives are correct. The mean value of 16 Ma indicates that the 15.7 Ma half-life of 129I used here for the I-Xe age calculations is most probably correct. Since the 129I half-life value only affects the relative I-Xe ages, the few Ma relative to the Shallowater standard, the absolute I-Xe ages are almost immune to this uncertainty in the 129I half-life.

Sex ratio variation shapes the ecological effects of a globally introduced freshwater fish

PubMed Central

Fryxell, David C.; Arnett, Heather A.; Apgar, Travis M.; Kinnison, Michael T.; Palkovacs, Eric P.

2015-01-01

Sex ratio and sexual dimorphism have long been of interest in population and evolutionary ecology, but consequences for communities and ecosystems remain untested. Sex ratio could influence ecological conditions whenever sexual dimorphism is associated with ecological dimorphism in species with strong ecological interactions. We tested for ecological implications of sex ratio variation in the sexually dimorphic western mosquitofish, Gambusia affinis. This species causes strong pelagic trophic cascades and exhibits substantial variation in adult sex ratios. We found that female-biased populations induced stronger pelagic trophic cascades compared with male-biased populations, causing larger changes to key community and ecosystem responses, including zooplankton abundance, phytoplankton abundance, productivity, pH and temperature. The magnitude of such effects indicates that sex ratio is important for mediating the ecological role of mosquitofish. Because both sex ratio variation and sexual dimorphism are common features of natural populations, our findings should encourage broader consideration of the ecological significance of sex ratio variation in nature, including the relative contributions of various sexually dimorphic traits to these effects. PMID:26490793

The Effect of Size and Ecology on Extinction Susceptibility

NASA Astrophysics Data System (ADS)

Huynh, C.; Yuan, A.; Heim, N.; Payne, J.

2015-12-01

Although life on Earth first emerged as prokaryotic organisms, it eventually evolved into billions of different species. However, extinctions on Earth, especially the five mass extinctions, have decimated species. So what leads to a species survival or demise during a mass extinction? Are certain species more susceptible to extinctions based on their size and ecology? For this project, we focused on the data of marine animals. To examine the impact of size and ecology on a species's likelihood of survival, we compared the sizes and ecologies of the survivors and victims of the five mass extinctions. The ecology, or life mode, of a genus consists of the combination of tiering, motility, and feeding mechanism. Tiering refers to the animal's typical location in the water column and sediments, motility refers to its ability to move, and feeding mechanism describes the way the organism eats; together, they describe the animal's behavior. We analyzed the effect of ecology on survival using logistic regression, which compares life mode to the success or failure of a genus during each mass extinction interval. For organism size, we found the extinct organisms' mean size (both volume and length) and compared it with the average size of survivors on a graph. Our results show that while surviving genera of mass extinctions tended to be slightly larger than those that went extinct, there was no significant difference. Even though the Permian (Changhsingian) and Triassic (Rhaetian) extinctions had larger surviving species, likewise the difference was small. Ecology had a more obvious impact on the likelihood of survival; fast-moving, predatory pelagic organisms were the most likely to go extinct, while sedentary, infaunal suspension feeders had the greatest chances of survival. Overall, ecology played a greater role than size in determining the survival of a species. With this information, we can use ecology to predict which species would survive future extinctions.

Demography of birds in a neotropical forest: Effects of allometry, taxonomy, and ecology

USGS Publications Warehouse

Brawn, J.D.; Karr, J.R.; Nichols, J.D.

1995-01-01

Comparative demographic studies of terrestrial vertebrates have included few samples of species from tropical forests. We analyzed 9 yr of mark-recapture data and estimated demographic parameters for 25 species of birds inhabiting lowland forests in central Panama. These species were all songbirds (Order Passeriformes) ranging in mass from 7 to 57 g. Using Jolly-Seber stochastic models for open populations, we estimated annual survival rate, population size, and recruitment between sampling periods for each species. We then explored relationships between these parameters and attributes such as body size, phylogenetic affiliation, foraging guild, and social behavior. Larger birds had comparatively long life-spans and low recruitment, but body size was not associated with population size. After adjusting for effects of body size, we found no association between phylogenetic affiliation and any demographic trait. Ecological attributes, especially foraging guild, were more clearly associated with interspecific variation in all demographic traits. Ant-followers had comparatively long life-spans, but species that participate in flocks did not live longer than solitary species. The allometric associations we observed were consistent with those demonstrated in other studies of vertebrates; thus. these relationships appear to be robust. Our finding that ecological factors were more influential than phylogenetic affiliation contrasts with comparative studies of temperate-zone birds and suggests that the relative importance of environmental vs. historical factors varies geographically.

Stable isotope turnover and half-life in animal tissues: a literature synthesis.

PubMed

Vander Zanden, M Jake; Clayton, Murray K; Moody, Eric K; Solomon, Christopher T; Weidel, Brian C

2015-01-01

Stable isotopes of carbon, nitrogen, and sulfur are used as ecological tracers for a variety of applications, such as studies of animal migrations, energy sources, and food web pathways. Yet uncertainty relating to the time period integrated by isotopic measurement of animal tissues can confound the interpretation of isotopic data. There have been a large number of experimental isotopic diet shift studies aimed at quantifying animal tissue isotopic turnover rate λ (%·day(-1), often expressed as isotopic half-life, ln(2)/λ, days). Yet no studies have evaluated or summarized the many individual half-life estimates in an effort to both seek broad-scale patterns and characterize the degree of variability. Here, we collect previously published half-life estimates, examine how half-life is related to body size, and test for tissue- and taxa-varying allometric relationships. Half-life generally increases with animal body mass, and is longer in muscle and blood compared to plasma and internal organs. Half-life was longest in ecotherms, followed by mammals, and finally birds. For ectotherms, different taxa-tissue combinations had similar allometric slopes that generally matched predictions of metabolic theory. Half-life for ectotherms can be approximated as: ln (half-life) = 0.22*ln (body mass) + group-specific intercept; n = 261, p<0.0001, r2 = 0.63. For endothermic groups, relationships with body mass were weak and model slopes and intercepts were heterogeneous. While isotopic half-life can be approximated using simple allometric relationships for some taxa and tissue types, there is also a high degree of unexplained variation in our models. Our study highlights several strong and general patterns, though accurate prediction of isotopic half-life from readily available variables such as animal body mass remains elusive.

Handbook for Evaluating Ecological Effects of Pollution at DARCOM installations. Volume 4. Terrestrial Surveys

DTIC Science & Technology

1979-12-01

AD RDTE Project No. ____________ TECOM Project No. O-CO-520-EOC-004 AYL) DPG Document No. DPG HB 80-804 0 HANDBOOK FOR EVALUATING ECOLOGICAL EFFECTS...NUMBER TECOM Project No. 0-C0-520-EQC-004’__ __" . .TITLEd . .5. TYPE OF REPORT PERIOD COVERED *! Handbook for Evaluating Ecological Effects of Pollution...IS. SUPPLEMENTARY NOTES Volume 4 of seven volumes dealing with evaluating ecological effects of pollution at DARCOM installations 19. KEY WORDS

On the Likelihood of Single-Walled Carbon Nanotubes Causing Adverse Marine Ecological Effects

EPA Science Inventory

This brief article discusses the ecological effects of single-walled carbon nanotubes (SWNTs)in the marine environment. Based on new research and a review of the scientific literature, the paper concludes that SWNTs are unlikely to cause adverse ecological effects in the marine ...

Evolving Digital Ecological Networks

PubMed Central

Wagner, Aaron P.; Ofria, Charles

2013-01-01

“It is hard to realize that the living world as we know it is just one among many possibilities” [1]. Evolving digital ecological networks are webs of interacting, self-replicating, and evolving computer programs (i.e., digital organisms) that experience the same major ecological interactions as biological organisms (e.g., competition, predation, parasitism, and mutualism). Despite being computational, these programs evolve quickly in an open-ended way, and starting from only one or two ancestral organisms, the formation of ecological networks can be observed in real-time by tracking interactions between the constantly evolving organism phenotypes. These phenotypes may be defined by combinations of logical computations (hereafter tasks) that digital organisms perform and by expressed behaviors that have evolved. The types and outcomes of interactions between phenotypes are determined by task overlap for logic-defined phenotypes and by responses to encounters in the case of behavioral phenotypes. Biologists use these evolving networks to study active and fundamental topics within evolutionary ecology (e.g., the extent to which the architecture of multispecies networks shape coevolutionary outcomes, and the processes involved). PMID:23533370

Utilizing Ecological Health Index to Monitor Grazingland Ecological Health: A Quick and Flexible Method for Ranchers and Farmers

NASA Astrophysics Data System (ADS)

Xu, S.; Borrelli, P. R.; Raven, M. R.; Rowntree, J. E.

2017-12-01

Grazing lands should be monitored to ensure their long-term productivity and sustainability. While monitoring protocols do exist, there is a need to simplify procedures for land managers while maintaining efficacy in order to increase usage. The objective in this study was to investigate the effectiveness of an Ecological Health Index (EHI) on indicating ecological health in grazing lands. We introduced the EHI, which was derived by synthesizing vegetation and soil cover indicators already existing in the literature to ranchers in Patagonia. Additionally, we implemented long-term transects at 44 farms from two ecological regions in Patagonia, the non-brittle Humid Magellan Steppe (HMS) (n=24) and the brittle Subandean Grasslands (SG) (n=20), to collect quantitative vegetative and soil measurements and correlated this back to EHI. In the non-brittle area HMS with even distribution of rainfall and good temperature which can support more plant biomass, the EHI ranged from -40 to 65 with a mean of 12.5 ± 24. The EHI from brittle SG ranged from -80 to 75 with a mean of 1.25 ± 35, which was 90% lower than the mean non-brittle EHI. From a quantitative perspective, HMS had greater species richness compared to SG (27 vs. 20, P=0.0003). Similarly, the average percentage of total live vegetation was higher in HMS than that in SG (77% vs. 48%, P < 0.0001). There was a positive correlation between EHI and carrying capacity. Mean HMS carrying capacity was 123 animal days per hectare (AD/ha) (P = 0.0022) which was greater compared to 35 AD/ha in SG. Moreover, our data indicate that EHI was positively correlated with species richness, the percentage of total live vegetation, and carrying capacity and it was negatively correlated with erosion pavement percentage and bare ground + erosion pavement (P < 0.05). These results suggest that EHI could be a useful method to detect the ecological health and productivity in grazing lands. Overall, we conclude that EHI is an effective short

Trends In Rhode Island Forests: A Half-Century of Change

Treesearch

Northeastern Research Station and Rhode Island Department of Environmental Management Division of Forest Environment

2002-01-01

Forests provide watershed protection, settings for recreation, wildlife habitat, biodiversity, wood and other products, and much more. Forests contribute to the quality of life of each Rhode Island resident making the State a better place in which to live. Some of the significant trends that have occurred in Rhode Island's forests over the last half century are...

Indoors and health: results of a systematic literature review assessing the potential health effects of living in basements.

PubMed

Mezzoiuso, Angelo Giosué; Gola, Marco; Rebecchi, Andrea; Riccò, Matteo; Capolongo, Stefano; Buffoli, Maddalena; Tirani, Marcello; Odone, Anna; Signorelli, Carlo

2017-10-23

A new law approved in March 2017 in the Lombardy Region makes it possible to live in basements. Basements are defined as buildings partly below curb level but with at least one-half of its height above the curb. Basements' features and structural characteristics might pose risks to human health. In this paper we adopt a multidisciplinary approach to assess the potential health effects of living in basements. In particular, we define a conceptual framework to describe basements' structural characteristics which are risk factors, as well as the mechanisms through which they impact on human health. We also conduct a systematic review on the scientific databases PubMed,Embase, DOAJ, Proquest and EBSCO to retrieve, pool and critically analyze all available research that quantified the risk of living in basements for different health outcomes. Available evidence suggests living in basements increases the risk of respiratory diseases (asthma and allergic disorders); more heterogeneous data are available for cancers and cardiovascular diseases. As more quantitative data need to be prospectively retrieved to assess and monitor the risk of living in basements for human health, clear minimum requirements for light, air, sanitation and egress are to be defined by technical experts and enforced by policy makers.

Antimicrobial Active Clothes Display No Adverse Effects on the Ecological Balance of the Healthy Human Skin Microflora

PubMed Central

Hoefer, Dirk; Hammer, Timo R.

2011-01-01

The progressive public use of antimicrobial clothes has raised issues concerning skin health. A placebo-controlled side-to-side study was run with antimicrobial clothes versus fabrics of similar structure but minus the antimicrobial activity, to evaluate possible adverse effects on the healthy skin microflora. Sixty volunteers were enrolled. Each participant received a set of form-fitting T-shirts constructed in 2 halves: an antibacterial half, displaying activities of 3–5 log-step reductions due to silver-finishes or silver-loaded fibres and a nonantibacterial control side. The microflora of the scapular skin was analyzed weekly for opportunistic and pathogenic microorganisms over six weeks. The antibacterial halves did not disturb the microflora in number or composition, whereas a silver-containing deodorant displayed a short-term disturbance. Furthermore, parameters of skin morphology and function (TEWL, pH, moisture) did not show any significant shifts. In summary, antimicrobial clothes did not show adverse effects on the ecological balance of the healthy skin microflora. PMID:22363849

Assessing the Effect of Musical Congruency on Wine Tasting in a Live Performance Setting

PubMed Central

Wang, Qian (Janice)

2015-01-01

At a wine tasting event with live classical music, we assessed whether participants would agree that certain wine and music pairings were congruent. We also assessed the effect of musical congruency on the wine tasting experience. The participants were given two wines to taste and two pieces of music—one chosen to match each wine—were performed live. Half of the participants tasted the wines while listening to the putatively more congruent music, the rest tasted the wines while listening to the putatively less congruent music. The participants rated the wine–music match and assessed the fruitiness, acidity, tannins, richness, complexity, length, and pleasantness of the wines. The results revealed that the music chosen to be congruent with each wine was indeed rated as a better match than the other piece of music. Furthermore, the music playing in the background also had a significant effect on the perceived acidity and fruitiness of the wines. These findings therefore provide further support for the view that music can modify the wine drinking experience. However, the present results leave open the question of whether the crossmodal congruency between music and wine itself has any overarching influence on the wine drinking experience. PMID:27433313

Current and future contraceptive options for women living with HIV

PubMed Central

Patel, Rena C.; Bukusi, Elizabeth A.; Baeten, Jared M.

2018-01-01

Introduction Among women living with HIV, half of the pregnancies are unintended. Effective contraception can prevent unintended pregnancies and consequently reduce maternal mortality and perinatal transmission of HIV. While contraceptive options available for all women also apply to women living with HIV, specific considerations exist to the use of contraception by women living with HIV. Areas covered First, general principles guiding the use of contraception among women living with HIV are discussed, such as choice, method mix, relative effectiveness, and drug-drug interactions. Second, a detailed discussion of each contraceptive method and issues surrounding the use of that method, such as drug-drug interactions, follows. Third, future contraceptive options in advanced development for use by women or men are briefly discussed. Expert opinion Contraceptive methods available to all women should also be accessible to women living with HIV. When the relative effectiveness of a contraceptive method is reduced, for example due to drug-drug interactions with antiretrovirals, the method should still be made available to women living with HIV with the appropriate information sharing and counseling. Greater research on various aspects of contraceptive use by women living with HIV and more comprehensive testing of co-administration of hormonal contraceptives and common medications used by these women are warranted. PMID:28891343

Current and future contraceptive options for women living with HIV.

PubMed

Patel, Rena C; Bukusi, Elizabeth A; Baeten, Jared M

2018-01-01

Among women living with HIV, half of the pregnancies are unintended. Effective contraception can prevent unintended pregnancies and consequently reduce maternal mortality and perinatal transmission of HIV. While contraceptive options available for all women also apply to women living with HIV, specific considerations exist to the use of contraception by women living with HIV. Areas covered: First, general principles guiding the use of contraception among women living with HIV are discussed, such as choice, method mix, relative effectiveness, and drug-drug interactions. Second, a detailed discussion of each contraceptive method and issues surrounding the use of that method, such as drug-drug interactions, follows. Third, future contraceptive options in advanced development for use by women or men are briefly discussed. Expert opinion: Contraceptive methods available to all women should also be accessible to women living with HIV. When the relative effectiveness of a contraceptive method is reduced, for example due to drug-drug interactions with antiretrovirals, the method should still be made available to women living with HIV with the appropriate information sharing and counseling. Greater research on various aspects of contraceptive use by women living with HIV and more comprehensive testing of co-administration of hormonal contraceptives and common medications used by these women are warranted.

Ethnobiology in the city: Embracing the urban ecological moment

Treesearch

Marla R. Emery; Patrick T. Hurley

2016-01-01

More than half the world's human population resides in cities (United Nations Economic and Social Affairs Population Division 2015)1. Unpacking this singular statistic, it becomes clear that people come to live in urban environments via numerous routes. Some have lived in cities all their lives and are descendants of city dwellers. In other...

Quantification of 60Fe atoms by MC-ICP-MS for the redetermination of the half-life.

PubMed

Kivel, Niko; Schumann, Dorothea; Günther-Leopold, Ines

2013-03-01

In many scientific fields, the half-life of radionuclides plays an important role. The accurate knowledge of this parameter has direct impact on, e.g., age determination of archeological artifacts and of the elemental synthesis in the universe. In order to derive the half-life of a long-lived radionuclide, the activity and the absolute number of atoms have to be analyzed. Whereas conventional radiation measurement methods are typically applied for activity determinations, the latter can be determined with high accuracy by mass spectrometric techniques. Over the past years, the half-lives of several radionuclides have been specified by means of multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) complementary to the earlier reported values mainly derived by accelerator mass spectrometry. The present paper discusses all critical aspects (amount of material, radiochemical sample preparation, interference correction, isotope dilution mass spectrometry, calculation of measurement uncertainty) for a precise analysis of the number of atoms by MC-ICP-MS exemplified for the recently published half-life determination of 60Fe (Rugel et al, Phys Rev Lett 103:072502, 2009).

Measurement of the half-life of 79Se with accelerator mass spectrometry

DOE PAGES

Dou, Liang; Jiang, Shan; Wang, Xiao-Bo; ...

2014-10-01

The accelerator mass spectrometry (AMS) is an effective method for the determination of the half-life of long-lived radionuclides. In this paper, we report a method for measurement of the half-life of 79Se. The number of 79Se atoms was determined from measured 79Se/Se absolute ratios with the AMS system at the China Institute of Atomic Energy and the decay rate of 79Se was determined by counting the emitted β-rays with a liquid scintillation spectrometer. The major improvements of our measurements include using the high abundance of an 79Se sample which was cooled for many years to exclude the interference of short-livedmore » nuclides, the extraction of SeO 2 - molecular ions, that results in a suppression of the 79 Br background by as much as about five orders of magnitude. Also, an AMS measurement of the absolute ratio of 79 Se/Se was developed to avoid systematic errors. The results show that 79 Se/Se is (2.35±0.12)×10 -7 in the reference sample and the radioactivity of 79Se is (1.24±0.05) Bq/g, so the half-life of 79Se is (2.78±0.18)×10 5 a.« less

Free-Living Nematodes in the Freshwater Food Web: A Review

PubMed Central

Majdi, Nabil; Traunspurger, Walter

2015-01-01

Free-living nematodes are well-recognized as an abundant and ubiquitous component of benthic communities in inland waters. Compelling evidence from soil and marine ecosystems has highlighted the importance of nematodes as trophic intermediaries between microbial production and higher trophic levels. However, the paucity of empirical evidence of their role in freshwater ecosystems has hampered their inclusion in our understanding of freshwater food web functioning. This literature survey provides an overview of research efforts in the field of freshwater nematode ecology and of the complex trophic interactions between free-living nematodes and microbes, other meiofauna, macro-invertebrates, and fishes. Based on an analysis of the relevant literature and an appreciation of the potential of emerging approaches for the evaluation of nematode trophic ecology, we point out research gaps and recommend relevant directions for further research. The latter include (i) interactions of nematodes with protozoans and fungi; (ii) nonconsumptive effects of nematodes on microbial activity and the effects of nematodes on associated key ecosystem processes (decomposition, primary production); and (iii) the feeding selectivity and intraspecific feeding variability of nematodes and their potential impacts on the structure of benthic communities. PMID:25861114

21 CFR 131.180 - Half-and-half.

Code of Federal Regulations, 2010 CFR

2010-04-01

...). (ii) Natural and artificial food flavoring. (c) Methods of analysis. The milkfat content is determined... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Half-and-half. 131.180 Section 131.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

21 CFR 131.180 - Half-and-half.

Code of Federal Regulations, 2013 CFR

2013-04-01

...). (ii) Natural and artificial food flavoring. (c) Methods of analysis. The milkfat content is determined... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Half-and-half. 131.180 Section 131.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

21 CFR 131.180 - Half-and-half.

Code of Federal Regulations, 2014 CFR

2014-04-01

...). (ii) Natural and artificial food flavoring. (c) Methods of analysis. The milkfat content is determined... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Half-and-half. 131.180 Section 131.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

21 CFR 131.180 - Half-and-half.

Code of Federal Regulations, 2011 CFR

2011-04-01

...). (ii) Natural and artificial food flavoring. (c) Methods of analysis. The milkfat content is determined... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Half-and-half. 131.180 Section 131.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

21 CFR 131.180 - Half-and-half.

Code of Federal Regulations, 2012 CFR

2012-04-01

...). (ii) Natural and artificial food flavoring. (c) Methods of analysis. The milkfat content is determined... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Half-and-half. 131.180 Section 131.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

Internet Use and Child Development: Validation of the Ecological Techno-Subsystem

ERIC Educational Resources Information Center

Johnson, Genevieve Marie

2010-01-01

Johnson and Puplampu recently proposed the "ecological techno-subsystem", a refinement to Bronfenbrenner's theoretical organization of environmental influences on child development. The ecological techno-subsystem includes child interaction with both living (e.g., peers) and nonliving (e.g., hardware) elements of communication,…

Protein half-life determines expression of proteostatic networks in podocyte differentiation.

PubMed

Schroeter, Christina B; Koehler, Sybille; Kann, Martin; Schermer, Bernhard; Benzing, Thomas; Brinkkoetter, Paul T; Rinschen, Markus M

2018-04-25

Podocytes are highly specialized, epithelial, postmitotic cells, which maintain the renal filtration barrier. When adapting to considerable metabolic and mechanical stress, podocytes need to accurately maintain their proteome. Immortalized podocyte cell lines are a widely used model for studying podocyte biology in health and disease in vitro. In this study, we performed a comprehensive proteomic analysis of the cultured human podocyte proteome in both proliferative and differentiated conditions at a depth of >7000 proteins. Similar to mouse podocytes, human podocyte differentiation involved a shift in proteostasis: undifferentiated podocytes have high expression of proteasomal proteins, whereas differentiated podocytes have high expression of lysosomal proteins. Additional analyses with pulsed stable-isotope labeling by amino acids in cell culture and protein degradation assays determined protein dynamics and half-lives. These studies unraveled a globally increased stability of proteins in differentiated podocytes. Mitochondrial, cytoskeletal, and membrane proteins were stabilized, particularly in differentiated podocytes. Importantly, protein half-lives strongly contributed to protein abundance in each state. These data suggest that regulation of protein turnover of particular cellular functions determines podocyte differentiation, a paradigm involving mitophagy and, potentially, of importance in conditions of increased podocyte stress and damage.-Schroeter, C. B., Koehler, S., Kann, M., Schermer, B., Benzing, T., Brinkkoetter, P. T., Rinschen, M. M. Protein half-life determines expression of proteostatic networks in podocyte differentiation.

Ecological characteristics of coral patch reefs at Midway Atoll, Northwestern Hawaiian Islands

USGS Publications Warehouse

Schroeder, R.E.; Parrish, J.D.

2006-01-01

Ecological aspects of coral patch reefs were studied from 1981 to 1985 in Welles Harbor, Midway Atoll. Water temperatures varied from 17??C in February to 28??C in August. Sizes of reefs studied were described by mean area (59 m2), mean volume (52 m3), vertical relief (<1 m), and inter-reef isolation (100 m). Considerable temporal change in reef size occurred due to large winter swells shifting bottom sand. Six common species accounted for 70% of all individual fish visually censused over 4 years. Overall fish assemblage composition ranged from 11 to 46 fish/10 m2, from 3 to 14 species. Numerical abundance and species richness for all fish (pooled) strongly correlated with physical reef substrate characteristics of area, volume, and vertical relief during summer. Species diversity (H') was not correlated with the substrate variables, suggesting similarity in the structure of fish communities among different sizes of patch reefs. Daily surveillance for presence of large transient taxa suggested that visits by sharks, large jacks, monk seals, sea turtles, and dolphins were infrequent. Density estimates were made for all conspicuous invertebrate megafauna during initial and final assessments. Six common taxa provided 90% of these counts; nearly half were sea urchins. Percent cover also was recorded for coral and algal species on the patch reefs. Cover by live coral was low (about 7%) and dominated by a few species. Mean algal cover ranged from 32 to 77%. Such information on ecological characteristics of reefs may aid in understanding complex ecological processes and provides an earlier reference for current ecosystem studies.

LIVING RESOURCES AND THEIR HABITATS ARE THE FOCUS OF THE GULF ECOLOGY DIVISION'S MISSION

EPA Science Inventory

This brief article introduces ERF Newsletter readers to the Gulf Ecology Division. Future articles will showcase our estuarine and near-coastal research efforts in areas such as biochemical and cellular toxicology, temporal and spatial scaling of ecological data, reproductive and...

A comparative perspective on longevity: the effect of body size dominates over ecology in moths.

PubMed

Holm, S; Davis, R B; Javoiš, J; Õunap, E; Kaasik, A; Molleman, F; Tammaru, T

2016-12-01

Both physiologically and ecologically based explanations have been proposed to account for among-species differences in lifespan, but they remain poorly tested. Phylogenetically explicit comparative analyses are still scarce and those that exist are biased towards homoeothermic vertebrates. Insect studies can significantly contribute as lifespan can feasibly be measured in a high number of species, and the selective forces that have shaped it may differ largely between species and from those acting on larger animals. We recorded adult lifespan in 98 species of geometrid moths. Phylogenetic comparative analyses were applied to study variation in species-specific values of lifespan and to reveal its ecological and life-history correlates. Among-species and between-gender differences in lifespan were found to be notably limited; there was also no evidence of phylogenetic signal in this trait. Larger moth species were found to live longer, with this result supporting a physiological rather than ecological explanation of this relationship. Species-specific lifespan values could not be explained by traits such as reproductive season and larval diet breadth, strengthening the evidence for the dominance of physiological determinants of longevity over ecological ones. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

Ecological effects of large fires on US landscapes: benefit or catastrophe?

Treesearch

Robert E. Keane; James K. Agee; Peter Fule; Jon E. Keeley; Carl Key; Stanley G. Kitchen; Richard Miller; Lisa A. Schulte

2008-01-01

The perception is that today's large fires are an ecological catastrophe because they burn vast areas with high intensities and severities. However, little is known of the ecological impacts of large fires on both historical and contemporary landscapes. The present paper presents a review of the current knowledge of the effects of large fires in the United States...

An improved method for determination of fumigant degradation half-life in soil

USDA-ARS?s Scientific Manuscript database

Using the current approach, measurement of fumigant degradation half-lives under realistic soil conditions is problematic due to the large headspace that is necessary above the soil during incubation. This results in a poor degree of contact between the fumigant and the soil’s degrading surfaces; di...

Disruptive ecological selection on a mating cue.

PubMed

Merrill, Richard M; Wallbank, Richard W R; Bull, Vanessa; Salazar, Patricio C A; Mallet, James; Stevens, Martin; Jiggins, Chris D

2012-12-22

Adaptation to divergent ecological niches can result in speciation. Traits subject to disruptive selection that also contribute to non-random mating will facilitate speciation with gene flow. Such 'magic' or 'multiple-effect' traits may be widespread and important for generating biodiversity, but strong empirical evidence is still lacking. Although there is evidence that putative ecological traits are indeed involved in assortative mating, evidence that these same traits are under divergent selection is considerably weaker. Heliconius butterfly wing patterns are subject to positive frequency-dependent selection by predators, owing to aposematism and Müllerian mimicry, and divergent colour patterns are used by closely related species to recognize potential mates. The amenability of colour patterns to experimental manipulation, independent of other traits, presents an excellent opportunity to test their role during speciation. We conducted field experiments with artificial butterflies, designed to match natural butterflies with respect to avian vision. These were complemented with enclosure trials with live birds and real butterflies. Our experiments showed that hybrid colour-pattern phenotypes are attacked more frequently than parental forms. For the first time, we demonstrate disruptive ecological selection on a trait that also acts as a mating cue.

Legacy effects in linked ecological-soil-geomorphic systems of drylands

USGS Publications Warehouse

Monger, Curtis; Sala, Osvaldo E.; Duniway, Michael C.; Goldfus, Haim; Meir, Isaac A.; Poch, Rosa M.; Throop, Heather L.; Vivoni, Enrique R.

2015-01-01

A legacy effect refers to the impacts that previous conditions have on current processes or properties. Legacies have been recognized by many disciplines, from physiology and ecology to anthropology and geology. Within the context of climatic change, ecological legacies in drylands (eg vegetative patterns) result from feedbacks between biotic, soil, and geomorphic processes that operate at multiple spatial and temporal scales. Legacy effects depend on (1) the magnitude of the original phenomenon, (2) the time since the occurrence of the phenomenon, and (3) the sensitivity of the ecological–soil–geomorphic system to change. Here we present a conceptual framework for legacy effects at short-term (days to months), medium-term (years to decades), and long-term (centuries to millennia) timescales, which reveals the ubiquity of such effects in drylands across research disciplines.

[Health effects of living habits].

PubMed

Vuori, Ilkka

2015-01-01

Single healthy living habits such as non-smoking and regular physical activity decrease the risk of common non-communicable diseases, unsuccessful aging and premature death to a small to moderate degree. Their cumulative effects are, however, large. Only a small minority of people adhere well to all healthy living habits or even the healthiest ones. Consequently, the population attributable fractions of major public health problems due to unhealthy lifestyles are large. Substantial improvement of public health calls for policies and programs to influence the root causes of the lifestyles in the multiple environments and systems where they are developed, maintained, and changed.

Modeling the effectiveness of oil combating from an ecological perspective--a Bayesian network for the Gulf of Finland; the Baltic Sea.

PubMed

Helle, Inari; Lecklin, Tiina; Jolma, Ari; Kuikka, Sakari

2011-01-15

Maritime traffic poses a major threat to marine ecosystems in the form of oil spills. The Gulf of Finland, the easternmost part of the Baltic Sea, has witnessed a rapid increase in oil transportation during the last 15 years. Should a spill occur, the negative ecological impacts may be reduced by oil combating, the effectiveness of which is, however, strongly dependent on prevailing environmental conditions and available technical resources. This poses increased uncertainty related to ecological consequences of future spills. We developed a probabilistic Bayesian network model that can be used to assess the effectiveness of different oil combating strategies in minimizing the negative effects of oil on six species living in the Gulf of Finland. The model can be used for creating different accident scenarios and assessing the performance of various oil combating actions under uncertainty, which enables its use as a supportive tool in decision-making. While the model is confined to the western Gulf of Finland, the methodology is adaptable to other marine areas facing similar risks and challenges related to oil spills. Copyright © 2010 Elsevier B.V. All rights reserved.

Promoting biodiversity values of small forest patches in agricultural landscapes: Ecological drivers and social demand.

PubMed

Varela, Elsa; Verheyen, Kris; Valdés, Alicia; Soliño, Mario; Jacobsen, Jette B; De Smedt, Pallieter; Ehrmann, Steffen; Gärtner, Stefanie; Górriz, Elena; Decocq, Guillaume

2018-04-01

Small forest patches embedded in agricultural (and peri-urban) landscapes in Western Europe play a key role for biodiversity conservation with a recognized capacity of delivering a wide suite of ecosystem services. Measures aimed to preserve these patches should be both socially desirable and ecologically effective. This study presents a joint ecologic and economic assessment conducted on small forest patches in Flanders (Belgium) and Picardie (N France). In each study region, two contrasted types of agricultural landscapes were selected. Open field (OF) and Bocage (B) landscapes are distinguished by the intensity of their usage and higher connectivity in the B landscapes. The social demand for enhancing biodiversity and forest structure diversity as well as for increasing the forest area at the expenses of agricultural land is estimated through an economic valuation survey. These results are compared with the outcomes of an ecological survey where the influence of structural features of the forest patches on the associated herbaceous diversity is assessed. The ecological and economic surveys show contrasting results; increasing tree species richness is ecologically more important for herbaceous diversity in the patch, but both tree species richness and herbaceous diversity obtain insignificant willingness to pay estimates. Furthermore, although respondents prefer the proposed changes to take place in the region where they live, we find out that social preferences and ecological effectiveness do differ between landscapes that represent different intensities of land use. Dwellers where the landscape is perceived as more "degraded" attach more value to diversity enhancement, suggesting a prioritization of initiatives in these area. In contrast, the ecological analyses show that prioritizing the protection and enhancement of the relatively better-off areas is more ecologically effective. Our study calls for a balance between ecological effectiveness and welfare

SPS microwave health and ecological effects: Program area overview

NASA Technical Reports Server (NTRS)

Cahill, D. F.

1980-01-01

The potential microwave health and ecological effects due to the operations of the Satellite Power System are discussed. An outline of the research needed to insure public acceptance of the program is presented.

Perfluorooctane Sulfonate Plasma Half-Life Determination and Long-Term Tissue Distribution in Beef Cattle (Bos taurus).

PubMed

Lupton, Sara J; Dearfield, Kerry L; Johnston, John J; Wagner, Sarah; Huwe, Janice K

2015-12-30

Perfluorooctane sulfonate (PFOS) is used in consumer products as a surfactant and is found in industrial and consumer waste, which ends up in wastewater treatment plants (WWTPs). PFOS does not breakdown during WWTP processes and accumulates in the biosolids. Common practices include application of biosolids to pastures and croplands used for feed, and as a result, animals such as beef cattle are exposed to PFOS. To determine plasma and tissue depletion kinetics in cattle, 2 steers and 4 heifers were dosed with PFOS at 0.098 mg/kg body weight and 9.1 mg/kg, respectively. Plasma depletion half-lives for steers and heifers were 120 ± 4.1 and 106 ± 23.1 days, respectively. Specific tissue depletion half-lives ranged from 36 to 385 days for intraperitoneal fat, back fat, muscle, liver, bone, and kidney. These data indicate that PFOS in beef cattle has a sufficiently long depletion half-life to permit accumulation in edible tissues.

Interactions between Genetic and Ecological Effects on the Evolution of Life Cycles.

PubMed

Rescan, Marie; Lenormand, Thomas; Roze, Denis

2016-01-01

Sexual reproduction leads to an alternation between haploid and diploid phases, whose relative length varies widely across taxa. Previous genetical models showed that diploid or haploid life cycles may be favored, depending on dominance interactions and on effective recombination rates. By contrast, niche differentiation between haploids and diploids may favor biphasic life cycles, in which development occurs in both phases. In this article, we explore the interplay between genetical and ecological factors, assuming that deleterious mutations affect the competitivity of individuals within their ecological niche and allowing different effects of mutations in haploids and diploids (including antagonistic selection). We show that selection on a modifier gene affecting the relative length of both phases can be decomposed into a direct selection term favoring the phase with the highest mean fitness (due to either ecological differences or differential effects of mutations) and an indirect selection term favoring the phase in which selection is more efficient. When deleterious alleles occur at many loci and in the presence of ecological differentiation between haploids and diploids, evolutionary branching often occurs and leads to the stable coexistence of alleles coding for haploid and diploid cycles, while temporal variations in niche sizes may stabilize biphasic cycles.

Ecosystem Encounters: Lessons in Synthetic Ecology.

ERIC Educational Resources Information Center

Adey, Walter H.

1992-01-01

The director of the Marine Systems Laboratory of the Smithsonian Institution discusses steps in developing ecological models. The following topics in using an aquarium for the ecosystem are described: lighting, water motion, water quality and filtration. Presents information on choosing living organisms for the ecosystem. Describes potential…

Ecological significance of residual exposures and effects from the Exxon Valdez oil spill.

PubMed

Harwell, Mark A; Gentile, John H

2006-07-01

An ecological significance framework is used to assess the ecological condition of Prince William Sound (PWS), Alaska, USA, in order to address the current management question: 17 y following the Exxon Valdez oil spill (EVOS), are there any remaining and continuing ecologically significant exposures or effects on the PWS ecosystem caused by EVOS? We examined the extensive scientific literature funded by the Exxon Valdez Trustees or by ExxonMobil to assess exposures and effects from EVOS. Criteria to assess ecological significance include whether a change in a valued ecosystem component (VEC) is sufficient to affect the structure, function, and/or health of the system and whether such a change exceeds natural variability. The EVOS occurred on 24 March 1989, releasing over 250,000 barrels of crude oil into PWS. Because PWS is highly dynamic, the residual oil was largely eliminated in the first few years, and now only widely dispersed, highly weathered, or isolated small pockets of residual contamination remain. Many other sources of polycyclic aromatic hydrocarbons (PAHs) exist in PWS from past or present human activities or natural oil seeps. Multiple-lines-of-evidence analyses indicate that residual PAHs from EVOS no longer represent an ecologically significant exposure risk to PWS. To assess the ecological significance of any residual effects from EVOS, we examined the literature on more than 20 VECs, including primary producers, filter feeders, fish and bird primary consumers, fish and bird top predators, a bird scavenger, mammalian primary consumers and top predators, biotic communities, ecosystem-level properties of trophodynamics and biogeochemical processes, and landscape-level properties of habitat mosaic and wilderness quality. None of these has any ecologically significant effects that are detectable at present, with the exception of 1 pod of orcas and possibly 1 subpopulation of sea otters; however, in both those cases, PWS-wide populations appear to have

A formula for half-life of proton radioactivity

NASA Astrophysics Data System (ADS)

Zhang, Zhi-Xing; Dong, Jian-Min

2018-01-01

We present a formula for proton radioactivity half-lives of spherical proton emitters with the inclusion of the spectroscopic factor. The coefficients in the formula are calibrated with the available experimental data. As an input to calculate the half-life, the spectroscopic factor that characterizes the important information on nuclear structure should be obtained with a nuclear many-body approach. This formula is found to work quite well, and in better agreement with experimental measurements than other theoretical models. Therefore, it can be used as a powerful tool in the investigation of proton emission, in particular for experimentalists. Supported by National Natural Science Foundation of China (11435014, 11405223, 11675265, 11575112), the 973 Program of China (2013CB834401, 2013CB834405), National Key Program for S&T Research and Development (2016YFA0400501), the Knowledge Innovation Project (KJCX2-EW-N01) of Chinese Academy of Sciences, the Funds for Creative Research Groups of China (11321064) and the Youth Innovation Promotion Association of Chinese Academy of Sciences

[Delineation of ecological security pattern based on ecological network].

PubMed

Fu, Qiang; Gu, Chao Lin

2017-03-18

Ecological network can be used to describe and assess the relationship between spatial organization of landscapes and species survival under the condition of the habitat fragmentation. Taking Qingdao City as the research area, woodland and wetland ecological networks in 2005 were simulated based on least cost path method, and the ecological networks were classified by their corridors' cumulative cost value. We made importance distinction of ecological network structure elements such as patches and corridors using betweenness centrality index and correlation length-percentage of importance of omitted patches index, and then created the structure system of ecological network. Considering the effects brought by the newly-added construction land from 2005 to 2013, we proposed the ecological security pattern for construction land change of Qingdao City. The results showed that based on ecological network framework, graph theory based methods could be used to quantify both attributes of specific ecological land (e.g., the area of an ecological network patch) and functional connection between ecological lands. Between 2005 and 2013, large area of wetlands had been destroyed by newly-added construction land, while the role of specific woodland and wetland played in the connection of the whole network had not been considered. The delineation of ecological security pattern based on ecological network could optimize regional ecological basis, provide accurate spatial explicit decision for ecological conservation and restoration, and meanwhile provide scientific and reasonable space guidance for urban spatial expansion.

Industrial ecology: a philosophical introduction.

PubMed Central

Frosch, R A

1992-01-01

By analogy with natural ecosystems, an industrial ecology system, in addition to minimizing waste production in processes, would maximize the economical use of waste materials and of products at the ends of their lives as inputs to other processes and industries. This possibility can be made real only if a number of potential problems can be solved. These include the design of wastes along with the design of products and processes, the economics of such a system, the internalizing of the costs of waste disposal to the design and choice of processes and products, the effects of regulations intended for other purposes, and problems of responsibility and liability. The various stakeholders in making the effects of industry on the environment more benign will need to adopt some new behaviors if the possibility is to become real. PMID:11607255

Ecological analysis of the health effects of income inequality in Argentina.

PubMed

De Maio, Fernando G

2008-05-01

Despite a large body of empirical literature, a consensus has not been reached concerning the health effects of income inequality. This study contributes to ongoing debates by examining the robustness of the income inequality-population health relationship in Argentina, using five different income inequality indexes (each sensitive to inequalities in differing parts of the income spectrum) and five measures of population health. Cross-sectional, ecological study. Income and self-reported morbidity data from Argentina's 2001 Encuesta de Condiciones de Vida (Survey of living conditions) were analysed at the provincial level. Provincial rates of male/female life expectancy and infant mortality were drawn from the Instituto Nacional de Estadistica y Censos database. Life expectancy was correlated in the expected direction with provincial-level income inequality (operationalized as the Gini coefficient) for both males (r=-0.55, P<0.01) and females (r=-0.61, P<0.01), but this association was not robust for all five income inequality indexes. In contrast, infant mortality, self-reported poor health and self-reported activity limitation were not correlated with any of the income inequality indexes. This study adds further complexity to the literature on the health effects of income inequality by highlighting the important effects of operational definitions. Mortality and morbidity data cannot be used as reasonably interchangeable variables (a common practice in this literature), and the choice of income inequality indicator may influence the results.

Ecology-Centered Experiences among Children and Adolescents: A Qualitative and Quantitative Analysis

ERIC Educational Resources Information Center

Orton, Judy

2013-01-01

The present research involved two studies that considered "ecology-centered experiences" (i.e., experiences with living things) as a factor in children's environmental attitudes and behaviors and adolescents' ecological understanding. The first study (Study 1) examined how a community garden provides children in an urban setting the…

[Scale effect of Li-Xiang Railway construction impact on landscape pattern and its ecological risk].

PubMed

Wang, De-zhi; Qiu, Peng-hua; Fang, Yuan-min

2015-08-01

As a large corridor project, plateau railway has multiple points and passes various sensitive environments along the railway. The determination of the scope of impact on ecological environment from railway construction is often controversial in ecological impact assessment work. Taking the Tangbu-Jiantang section of Li-Xiang Railway as study object, and using present land use map (1:10000) in 2012 and DEM as data sources, corridor cutting degree index ( CCI) and cumulative effect index of corridor (CCEI) were established by topology, buffer zone and landscape metrics methods. Besides, the ecological risk index used for railway construction was improved. By quantitative analysis of characteristics of the spatio-temporal change of landscape pattern and its evolution style at different spatial scales before and after railway construction, the most appropriate evaluation scale of the railway was obtained. Then the characteristics of the spatio-temporal variation of ecological risk within this scale before and after railway construction were analyzed. The results indicated that the cutting model and degree of railway corridor to various landscape types could be effectively reflected by CCI, and the exposure and harm relations between risk sources and risk receptors of railway can be measured by CCEI. After the railway construction, the railway corridor would cause a great deal of middle cutting effect on the landscape along the railroad, which would influence wood land and grassland landscape most greatly, while would cause less effect of edge cutting and internal cutting. Landscape indices within the 600 m buffer zone demonstrated the most obvious scale effect, therefore, the 600 m zone of the railway was set as the most suitable range of ecological impact assessment. Before railway construction, the low ecological risk level covered the biggest part of the 600 m assessment zone. However, after the railway construction, the ecological risk increased significantly, and

Two prospective Li-based half-Heusler alloys for spintronic applications based on structural stability and spin–orbit effect

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

Zhang, R. L.; Damewood, L.; Zeng, Y. J.

To search for half-metallic materials for spintronic applications, instead of using an expensive trial-and-error experimental scheme, it is more efficient to use first-principles calculations to design materials first, and then grow them. In particular, using a priori information of the structural stability and the effect of the spin–orbit interaction (SOI) enables experimentalists to focus on favorable properties that make growing half-metals easier. We suggest that using acoustic phonon spectra is the best way to address the stability of promising half-metallic materials. Additionally, by carrying out accurate first-principles calculations, we propose two criteria for neglecting the SOI so the half-metallicity persists.more » As a result, based on the mechanical stability and the negligible SOI, we identified two half-metals, β-LiCrAs and β-LiMnSi, as promising half-Heusler alloys worth growing.« less

Two prospective Li-based half-Heusler alloys for spintronic applications based on structural stability and spin–orbit effect

DOE PAGES

Zhang, R. L.; Damewood, L.; Zeng, Y. J.; ...

2017-07-07

To search for half-metallic materials for spintronic applications, instead of using an expensive trial-and-error experimental scheme, it is more efficient to use first-principles calculations to design materials first, and then grow them. In particular, using a priori information of the structural stability and the effect of the spin–orbit interaction (SOI) enables experimentalists to focus on favorable properties that make growing half-metals easier. We suggest that using acoustic phonon spectra is the best way to address the stability of promising half-metallic materials. Additionally, by carrying out accurate first-principles calculations, we propose two criteria for neglecting the SOI so the half-metallicity persists.more » As a result, based on the mechanical stability and the negligible SOI, we identified two half-metals, β-LiCrAs and β-LiMnSi, as promising half-Heusler alloys worth growing.« less

Minding the ecological body: neuropsychoanalysis and ecopsychoanalysis.

PubMed

Dodds, Joseph

2013-01-01

Neuropsychoanalysis explores experimentally and theoretically the philosophically ancient discussion of the relation of mind and body, and seems well placed to overcome the problem of a "mindless" neuroscience and a "brainless" psychology and psychotherapy, especially when combined with a greater awareness that the body itself, not only the brain, provides the material substrate for the emergent phenomenon we call mind. However, the mind-brain-body is itself situated within a complex ecological world, interacting with other mind-brain-bodies and the "non-human environment." This occurs both synchronically and diachronically as the organism and its environment (living and non-living) interact in highly complex often non-linear ways. Psychoanalysis can do much to help unmask the anxieties, deficits, conflicts, phantasies, and defenses crucial in understanding the human dimension of the ecological crisis. Yet, psychoanalysis still largely remains not only a "psychology without biology," which neuropsychoanalysis seeks to remedy, but also a "psychology without ecology." Ecopsychoanalysis (Dodds, 2011b; Dodds and Jordan, 2012) is a new transdisciplinary approach drawing on a range of fields such as psychoanalysis, psychology, ecology, philosophy, science, complexity theory, esthetics, and the humanities. It attempts to play with what each approach has to offer in the sense of a heterogeneous assemblage of ideas and processes, mirroring the interlocking complexity, chaos, and turbulence of nature itself. By emphasizing the way the mind-brain-body studied by neuropsychoanalysis is embedded in wider social and ecological networks, ecopsychoanalysis can help open up the relevance of neuropsychoanalysis to wider fields of study, including those who are concerned with what Wilson (2003) called "the future of life."

Minding the Ecological Body: Neuropsychoanalysis and Ecopsychoanalysis

PubMed Central

Dodds, Joseph

2013-01-01

Neuropsychoanalysis explores experimentally and theoretically the philosophically ancient discussion of the relation of mind and body, and seems well placed to overcome the problem of a “mindless” neuroscience and a “brainless” psychology and psychotherapy, especially when combined with a greater awareness that the body itself, not only the brain, provides the material substrate for the emergent phenomenon we call mind. However, the mind-brain-body is itself situated within a complex ecological world, interacting with other mind-brain-bodies and the “non-human environment.” This occurs both synchronically and diachronically as the organism and its environment (living and non-living) interact in highly complex often non-linear ways. Psychoanalysis can do much to help unmask the anxieties, deficits, conflicts, phantasies, and defenses crucial in understanding the human dimension of the ecological crisis. Yet, psychoanalysis still largely remains not only a “psychology without biology,” which neuropsychoanalysis seeks to remedy, but also a “psychology without ecology.” Ecopsychoanalysis (Dodds, 2011b; Dodds and Jordan, 2012) is a new transdisciplinary approach drawing on a range of fields such as psychoanalysis, psychology, ecology, philosophy, science, complexity theory, esthetics, and the humanities. It attempts to play with what each approach has to offer in the sense of a heterogeneous assemblage of ideas and processes, mirroring the interlocking complexity, chaos, and turbulence of nature itself. By emphasizing the way the mind-brain-body studied by neuropsychoanalysis is embedded in wider social and ecological networks, ecopsychoanalysis can help open up the relevance of neuropsychoanalysis to wider fields of study, including those who are concerned with what Wilson (2003) called “the future of life.” PMID:23533027

Improved measurement of the half-life of the J π = 8 - nuclear isomer 152m2 Eu

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

Humby, Peter; Simon, Anna; Beausang, C. W.

2015-02-23

The standard γ-ray energy calibration source 152Eu is well known based on the 13.5 y decay of its ground state. Nevertheless, in addition to this decay 152Eu also has two relatively long-lived isomeric states: a 9 h J π=0 - state at E *=46 keV and a 96 min J π=8 - state at E *=148 keV. Here we report a new measurement of the half-lives of both of these isomeric states. Excited states in 152Eu were populated following the 154Sm (p,3n) reaction using a 25 MeV proton beam from the K-150 cyclotron at the Cyclotron Institute of Texas A&Mmore » University. Post irradiation, γ rays from the de-excitation of the long lived isomeric states were measured using the six BGO shielded high-purity germanium (HPGe) clover detectors that are part of the STARLiTeR array. The half-life of the J π=8 - isomer 152m2Eu was obtained by measuring the decrease in intensity of the 90 keV γ ray from the cascade to the ground state. The half-life of this state was measured to be 95.8(4) min which is in agreement with and significantly more precise than the previously measured value of 96(1) min. In a manner similar to the ground state the second long-lived isomer 151m1Eu, the J π=0 - state at 46 keV, β decays to excited states in 152Gd and 152Sm. Also, the half-life of this state was measured to be 9.39(7) h using five γ-ray transitions.« less

How Do the Chinese Perceive Ecological Risk in Freshwater Lakes?

PubMed Central

Huang, Lei; Han, Yuting; Zhou, Ying; Gutscher, Heinz; Bi, Jun

2013-01-01

In this study, we explore the potential contributions of a risk perception framework in understanding public perceptions of unstable ecosystems. In doing so, we characterize one type of common ecological risk– harmful algal blooms (HABs)–in four of the most seriously eutrophicated freshwater lakes in China. These lakes include Chaohu, Dianchi, Hongze, and Taihu, where a total of 2000 residents living near these sites were interviewed. Regional discrepancies existed in the pilot study regarding public perceptions of ecological changes and public concerns for ecological risk. Comparing HABs and other kinds of risks (earthquake, nuclear, and public traffic) through the psychometric paradigm method, Knowledge, Effect, and Trust were three key factors formulating the risk perception model. The results indicated that Knowledge and risk tolerance levels had significant negative correlations in the higher economic situation while correlations in the lower economic situation were significantly positive. Effect and risk tolerance levels had significant negative correlations in the high and middle education situation while correlations in the low education situation were close to zero or insignificant. For residents from Taihu with comparatively higher economic and educational levels, more investment in risk prevention measures and stronger policies are needed. And for residents from Hongze and Dianchi with comparatively low economic and educational levels, improvement of the government’s credibility (Trust) was the most important factor of risk tolerance, so efforts to eliminate ecological problems with the stepwise development of economic and educational levels should be implemented and gradually strengthened. In turn, this could prevent public discontent and ensure support for ecological protection policies. PMID:23671602

Living in poverty in America today.

PubMed

Holosko, Michael J; Feit, Marvin D

2005-01-01

No statistician, social scientist or tarot card reader is needed to attest that the gap between the rich and poor in America is increasing. Further, most Americans don't care that much about it. There are also more rich people today living in the U.S. and there are more people living in poverty. Between 2000 and 2002, the number of Americans living in poverty increased by nearly 3 million to 34.6 million. Of these, 12% (or about one half a million persons) are living extreme poverty and many are children, with 16.7% likely to be poor (National Association of Social Workers, 2003).

Human metabolism and ecological transfer of radioactive caesium: Comparative studies of Chernobyl debris and nuclear weapons fallout, in Southern Sweden and in Bryansk, Russia

NASA Astrophysics Data System (ADS)

Raaf, Christopher Leopold

The whole-body content of radiocaesium was measured in a South-Swedish urban group of people residing in the city of Lund (55.7°N, 13.2°E) between 1960 and 1994. The results from the survey have been analysed in order to estimate the ecological half-time, Teff,eco, of fallout radiocaesium and the aggregate transfer from ground deposition to man in the region. After 1987, the biological half-times, Ts, of 137Cs and 40K in man were also determined in the reference group through whole-body content measurements in combination with 24-hour urine sampling. Relationships between 24-hour urinary excretion and body burden of 137Cs in the group together with data from the literature were then applied to urine samples collected in 1994 and 1995 from adult subjects living in the highly contaminated region of Bryansk, Russia, in order to estimate their average body burden of 137Cs. The equivalent biological half-time for 137Cs in females of the Lund reference group was, on average (+/-1 WSE), 66 +/- 3 d, which agrees with other findings, whereas the value for the males, 81 +/- 4 d, was, on average, significantly lower than what is found in the literature. This is partly explained by the elevated mean age and relatively low mean body muscle mass of the males investigated in the group during the post-Chernobyl study period. The effective ecological half-time for 137Cs from Chernobyl was found to be 1.8 +/- 0.2 y. The aggregate transfer of 137Cs from deposition to mean activity concentration in man was estimated to be 1.7 Bq kg-1/kBq m-2. These vales may be compared with an effective ecological half-time of 1.3 years found in the reference group in the 1960s, and an aggregate transfer factor of 9.8 Bq kg-1/kBq m-2. The average committed effective dose from ingested 137Cs Chernobyl fallout in the study group was estimated to be 0.02 mSv and from the nuclear weapons fallout to 0.20 mSv. The estimates of whole-body content of 137Cs in the Russian subjects obtained through

Edge Effects and Ecological Traps: Effects on Shrubland Birds in Missouri

Treesearch

April A. Woodward; Alix D. Fink; Frank R. Thompson III

2001-01-01

The effect of habitat edge on avian nesting success has been the focus of considerable debate. We studied relationships between habitat edges, locations of nests, and predation. We tested the ecological trap hypothesis for 5 shrubland bird species in the Missouri Ozarks. We compared habitat selection and daily nest predation rates among 3 distance-to-edge categories....

Revolutionary Ecologies: Ecosocialism and Critical Pedagogy

ERIC Educational Resources Information Center

McLaren, Peter; Houston, Donna

2004-01-01

In this article, we argue that critical and revolutionary educational praxis is increasingly shaped by and through ecological politics and imaginaries. Indeed, given the pervasiveness of environmental crisis in our everyday lives and vocabularies, we argue that critical educators can no longer ignore questions of ecojustice. In keeping with a…

Measurement of the half-life of {sup 198}Au in a nonmetal: High-precision measurement shows no host-material dependence

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

Goodwin, J. R.; Nica, N.; Iacob, V. E.

2010-10-15

We have measured the half-life of the {beta}{sup -} decay of {sup 198}Au to be 2.6948(9) d, with the nuclide sited in an insulating environment. Comparing this result with the half-life we measured previously with a metallic environment, we find the half-lives in both environments to be the same within 0.04%, thus contradicting a prediction that screening from a ''plasma'' of quasifree electrons in a metal increases the half-life by as much as 7%.

Deposition of gamma emitters from Chernobyl accident and their transfer in lichen-soil columns.

PubMed

Lehto, Jukka; Paatero, Jussi; Pehrman, Reijo; Kulmala, Seija; Suksi, Juhani; Koivula, Teija; Jaakkola, Timo

2008-10-01

Lichen-soil column samples were taken from several locations in the Southern Finland between 1986 and 2006. Columns were divided into three parts, upper lichen, lower lichen and underlying soil, and their gamma emitting radionuclides, 134Cs, 137Cs, 103Ru, 95Zr, 106Ru, 110mAg, 125Sb and 144Ce, were measured with gamma spectrometry. Deposition values were calculated as Bq/m2 for each sampling site. Distribution of various radionuclides in the three compartments as a function of time was determined. Both effective and ecological half-lives of all radionuclides were calculated for upper lichen, whole lichen and whole lichen-soil column. A linear relation was derived between the physical half-lives and effective half-lives for whole lichen and for whole lichen-soil column. Reindeer meat activity concentrations of various radionuclides and ensuing radiation doses to reindeer-herding people were also estimated for a hypothetical case where a similar high radioactive pollution, as was taken place in the Southern Finland, would have occurred in the reindeer-herding areas in the Finnish Lapland.

Ecological Interventionist Causal Models in Psychosis: Targeting Psychological Mechanisms in Daily Life

PubMed Central

Reininghaus, Ulrich; Depp, Colin A.; Myin-Germeys, Inez

2016-01-01

Integrated models of psychotic disorders have posited a number of putative psychological mechanisms that may contribute to the development of psychotic symptoms, but it is only recently that a modest amount of experience sampling research has provided evidence on their role in daily life, outside the research laboratory. A number of methodological challenges remain in evaluating specificity of potential causal links between a given psychological mechanism and psychosis outcomes in a systematic fashion, capitalizing on longitudinal data to investigate temporal ordering. In this article, we argue for testing ecological interventionist causal models that draw on real world and real-time delivered, ecological momentary interventions for generating evidence on several causal criteria (association, time order, and direction/sole plausibility) under real-world conditions, while maximizing generalizability to social contexts and experiences in heterogeneous populations. Specifically, this approach tests whether ecological momentary interventions can (1) modify a putative mechanism and (2) produce changes in the mechanism that lead to sustainable changes in intended psychosis outcomes in individuals’ daily lives. Future research using this approach will provide translational evidence on the active ingredients of mobile health and in-person interventions that promote sustained effectiveness of ecological momentary interventions and, thereby, contribute to ongoing efforts that seek to enhance effectiveness of psychological interventions under real-world conditions. PMID:26707864

EPA'S ECOLOGICAL EFFECTS BRANCH: PLANNING FOR AN UNCERTAIN FUTURE

EPA Science Inventory

The seminar will address two topics: 1) a brief overview of Dr. Hammer’s professional experiences that preceded his appointment with the Environmental Protection Agency; and 2) a summary of current projects being planned by the Ecological Effects Branch of the Environmental Prote...

The Role of Mental Imagery in Imaginative and Ecological Teaching

ERIC Educational Resources Information Center

Judson, Gillian

2014-01-01

This article explores how mental imagery evoked from words might enhance the learning of cross-curricular content and how it may help cultivate students' "ecological understanding": that deep sense of connection to a living world and the care and concern to live differently within it. With reference to Elliott Eisner's and Kieran Egan's…

Quantitative analysis of ecological effects for land use planning based on ecological footprint method: a case research in Nanyang City

NASA Astrophysics Data System (ADS)

Zhang, Jing; Liu, Yaolin; Chen, Xinming

2008-10-01

The research of coordinated development between land use and ecological building is a new problem with the development of country economy, whose intention is to improve economy development and protect eco-environment in order to realize regional sustainable development. Evaluating human effects on the ecosystem by a comprehensive, scientific and quantitative method is a critical issue in the process of general land use planning. At present, ecological footprint methodology, as an excellent educational tool applicable to global issues, is essential for quantifying humanity's consumption of natural capital, for overall assessments of human impact on earth as well as for general land use planning. However, quantitative studies on the development trends of ecological footprint (EF) time series and biological capacity (BC) time series in a given region are still rare. Taking Nanyang City as a case study, this paper presents two quantitative estimate indices over time scale called the change rate and scissors difference to quantitatively analyze the trends of EF and BC over the planning period in general land use planning form 1997-2004 and to evaluate the ecological effects of the land use general planning form 1997 to.2010. The results showed that: 1 In Nanyang city, trends of the per capita EF and BC were on the way round, and the ecological deficit enhanced from 1997 to 2010. 2 The difference between the two development trends of per capita EF and BC had been increasing rapidly and the conflict between the EF and BC was aggravated from 1997 to 2010. 3 The general land use planning (1997 - 2010) of Nanyang city had produced some positive effects on the local ecosystem, but the expected biological capacity in 2010 can hardly be realized following this trend. Therefore, this paper introduces a "trinity" land use model in the guidelines of environment- friendly land use pattern and based on the actual situation of Nanyang city, with the systemic synthesis of land

Examining Lives in Context: Perspectives on the Ecology of Human Development.

ERIC Educational Resources Information Center

Moen, Phyllis, Ed.; And Others

Extending the work of behavioral scientist Urie Bronfenbrenner on the social and contextual factors influencing human development, this collection of essays, from scholars in a range of disciplines, shows how Bronfenbrenner's ecological theory and research have transformed the way many social and behavioral scientists approach, think about, and…

First application of combined isochronous and Schottky mass spectrometry: Half-lives of fully ionized Cr 24 + 49 and Fe 26 + 53 atoms

NASA Astrophysics Data System (ADS)

Tu, X. L.; Chen, X. C.; Zhang, J. T.; Shuai, P.; Yue, K.; Xu, X.; Fu, C. Y.; Zeng, Q.; Zhou, X.; Xing, Y. M.; Wu, J. X.; Mao, R. S.; Mao, L. J.; Fang, K. H.; Sun, Z. Y.; Wang, M.; Yang, J. C.; Litvinov, Yu. A.; Blaum, K.; Zhang, Y. H.; Yuan, Y. J.; Ma, X. W.; Zhou, X. H.; Xu, H. S.

2018-01-01

Lifetime measurements of β -decaying highly charged ions have been performed in the experimental storage ring (CSRe) by applying the isochronous Schottky mass spectrometry. The fully ionized 49Cr and 53Fe ions were produced in projectile fragmentation of 58Ni primary beam and were stored in the CSRe tuned into the isochronous ion-optical mode. The new resonant Schottky detector was applied to monitor the intensities of stored uncooled Cr 24 + 49 and Fe 26 + 53 ions. The extracted half-lives T1 /2(Cr 24 + 49 ) =44.0 (27 ) min and T1 /2(Fe 26 + 53 ) =8.47 (19 ) min are in excellent agreement with the literature half-life values corrected for the disabled electron capture branchings. This is an important proof-of-principle step towards realizing the simultaneous mass and lifetime measurements on exotic nuclei at the future storage ring facilities.

Low ecological disparity in Early Cretaceous birds

PubMed Central

Mitchell, Jonathan S.; Makovicky, Peter J.

2014-01-01

Ecological divergence is thought to be coupled with evolutionary radiations, yet the strength of this coupling is unclear. When birds diversified ecologically has received much less attention than their hotly debated crown divergence time. Here, we quantify how accurately skeletal morphology can predict ecology in living and extinct birds, and show that the earliest known assemblage of birds (= pygostylians) from the Jehol Biota (≈ 125 Ma) was substantially impoverished ecologically. The Jehol avifauna has few representatives of highly preservable ecomorphs (e.g. aquatic forms) and a notable lack of ecomorphological overlap with the pterosaur assemblage (e.g. no large or aerially foraging pygostylians). Comparisons of the Jehol functional diversity with modern and subfossil avian assemblages show that taphonomic bias alone cannot explain the ecomorphological impoverishment. However, evolutionary simulations suggest that the constrained ecological diversity of the Early Cretaceous pygostylians is consistent with what is expected from a relatively young radiation. Regardless of the proximate biological explanation, the anomalously low functional diversity of the Jehol birds is evidence both for ecological vacancies in Cretaceous ecosystems, which were subsequently filled by the radiation of crown Aves, and for discordance between taxonomic richness and ecological diversity in the best-known Mesozoic ecosystem. PMID:24870044

Pack rats (Neotoma spp.): Keystone ecological engineers?

USDA-ARS?s Scientific Manuscript database

The potential role of two species of pack rats (Neotoma albigula and Neotoma micropus) as keystone ecological engineers was examined by estimating the species diversity of invertebrates living in the nest middens, and nitrogen mineralization rates in soils associated with the middens. Although pack-...

Apparent Half-Lives of Dioxins, Furans, and Polychlorinated Biphenyls as a Function of Age, Body Fat, Smoking Status, and Breast-Feeding

PubMed Central

Milbrath, Meghan O’Grady; Wenger, Yvan; Chang, Chiung-Wen; Emond, Claude; Garabrant, David; Gillespie, Brenda W.; Jolliet, Olivier

2009-01-01

Objective In this study we reviewed the half-life data in the literature for the 29 dioxin, furan, and polychlorinated biphenyl congeners named in the World Health Organization toxic equivalency factor scheme, with the aim of providing a reference value for the half-life of each congener in the human body and a method of half-life estimation that accounts for an individual’s personal characteristics. Data sources and extraction We compared data from > 30 studies containing congener-specific elimination rates. Half-life data were extracted and compiled into a summary table. We then created a subset of these data based on defined exclusionary criteria. Data synthesis We defined values for each congener that approximate the half-life in an infant and in an adult. A linear interpolation of these values was used to examine the relationship between half-life and age, percent body fat, and absolute body fat. We developed predictive equations based on these relationships and adjustments for individual characteristics. Conclusions The half-life of dioxins in the body can be predicted using a linear relationship with age adjusted for body fat, smoking, and breast-feeding. Data suggest an alternative method based on a linear relationship between half-life and total body fat, but this approach requires further testing and validation with individual measurements. PMID:19337517

Genome rearrangement shapes Prochlorococcus ecological adaptation.

PubMed

Yan, Wei; Wei, Shuzhen; Wang, Qiong; Xiao, Xilin; Zeng, Qinglu; Jiao, Nianzhi; Zhang, Rui

2018-06-18

Prochlorococcus is the most abundant and smallest known free-living photosynthetic microorganism and is a key player in marine ecosystems and biogeochemical cycles. Prochlorococcus can be broadly divided into high-light-adapted (HL) and low-light-adapted (LL) clades. In this study, we isolated two low-light-adapted I (LLI) strains from the western Pacific Ocean and obtained their genomic data. We reconstructed Prochlorococcus evolution based on genome rearrangement. Our results showed that genome rearrangement might have played an important role in Prochlorococcus evolution. We also found that the Prochlorococcus clades with streamlined genomes maintained relatively high synteny throughout most of their genomes, and several regions served as rearrangement hotspots. Backbone analysis showed that different clades shared a conserved backbone but also had clade-specific regions, and the genes in these regions were associated with ecological adaptations. Importance Prochlorococcus , the most abundant and smallest known free-living photosynthetic microorganism, play a key role in marine ecosystems and biogeochemical cycles. The Prochlorococcus genome evolution is a fundamental question related to how Prochlorococcus clades adapted to different ecological niches. Recent studies revealed that the gene gain and loss is crucial to the clade differentiation. The significance of our research is that we interpreted the Prochlorococcus genome evolution from the perspective of genome structure, and associated the genome rearrangement with the Prochlorococcus clade differentiation and subsequent ecological adaptation. Copyright © 2018 Yan et al.

Mobile Phone Ecological Momentary Assessment of Daily Stressors Among People Living With HIV: Elucidating Factors Underlying Health-Related Challenges in Daily Routines.

PubMed

Farmer, Shu; Mindry, Deborah; Comulada, W Scott; Swendeman, Dallas

Stressful life events and daily hassles affect people living with HIV (PLWH). However, capturing stress-related events and cognitive impairment is often plagued with recall biases. Incorporating reliable information technology, such as mobile phones, can be a resourceful method for measuring health behaviors (MHB). We report findings from an MHB pilot study with 32 African American, Latino/Hispanic, and White PLWH from Los Angeles. Participants reported perceived stressors in their daily routines using a smartphone Ecological Momentary Assessment (EMA) application. Participants self-initiated in-the-moment stressful events reports for up to 6 weeks. Stressful event EMAs queried perceived stress levels (1-10 scale) and open-ended text descriptions. Qualitative analysis of participant text responses was completed using grounded thematic coding. Participants reported multiple stressors in their daily routines, impacting activities of daily living or daily functioning. Eliciting input from PLWH via EMA in real time is a novel approach for assessing and identifying sources of stress. Copyright © 2017 Association of Nurses in AIDS Care. Published by Elsevier Inc. All rights reserved.

Forests and landscapes: linking ecology, sustainability and aesthetics

Treesearch

Paul H. Gobster

2001-01-01

The prairies of the Midwestern US seem like an unlikely place for me to comment on the friuts of a workshop inspired by the forest of Canada's Pacific Northwest. But it is from this smae vantage point, more than a half-century earlier, that Aldo Leopold outlined the elements of what has been called an ecological aesthetic, a way of beholding the...

Happier countries, longer lives: an ecological study on the relationship between subjective sense of well-being and life expectancy.

PubMed

Evans, Grahame F; Soliman, Elsayed Z

2017-08-01

The relationship between sense of well-being and longevity is not well-established across populations of varying levels of socioeconomic status. We sought to examine the relationship between happiness, or subjective sense of well-being and life expectancy using data from 151 countries. This analysis is based on the 2012 Happy Planet Index project conducted by the Center of Well-Being of the New Economics Foundation, based in the United Kingdom. Well-being data for each country were taken from responses to the 'Ladder of Life' question in the 2012 Gallup World Poll in which participants were asked to rate their quality of life on a scale from 1 (worst possible life) to 10 (best possible life). Life expectancy and gross domestic product data were taken from the 2011 United Nations records. Ecological footprint data were taken from Global Footprint Network records. Subjective sense of well-being was highly correlated with life expectancy (Pearson correlation r = 0.71, p < 0.0001). In a multivariable linear regression model adjusted for gross domestic product, ecological footprint, and population, each 1 unit of the well-being scale was associated with an increase in life expectancy of 4.0 years (95% confidence interval = 2.7-5.3). In conclusion, better sense of well-being has a strong relationship with life expectancy regardless of economic status or population size, suggesting that governments should foster happiness in order to support long-living populations.

Cost-effective conservation of amphibian ecology and evolution

PubMed Central

Campos, Felipe S.; Lourenço-de-Moraes, Ricardo; Llorente, Gustavo A.; Solé, Mirco

2017-01-01

Habitat loss is the most important threat to species survival, and the efficient selection of priority areas is fundamental for good systematic conservation planning. Using amphibians as a conservation target, we designed an innovative assessment strategy, showing that prioritization models focused on functional, phylogenetic, and taxonomic diversity can include cost-effectiveness–based assessments of land values. We report new key conservation sites within the Brazilian Atlantic Forest hot spot, revealing a congruence of ecological and evolutionary patterns. We suggest payment for ecosystem services through environmental set-asides on private land, establishing potential trade-offs for ecological and evolutionary processes. Our findings introduce additional effective area-based conservation parameters that set new priorities for biodiversity assessment in the Atlantic Forest, validating the usefulness of a novel approach to cost-effectiveness–based assessments of conservation value for other species-rich regions. PMID:28691084

Global dynamics of a nonlocal delayed reaction-diffusion equation on a half plane

NASA Astrophysics Data System (ADS)

Hu, Wenjie; Duan, Yueliang

2018-04-01

We consider a delayed reaction-diffusion equation with spatial nonlocality on a half plane that describes population dynamics of a two-stage species living in a semi-infinite environment. A Neumann boundary condition is imposed accounting for an isolated domain. To describe the global dynamics, we first establish some a priori estimate for nontrivial solutions after investigating asymptotic properties of the nonlocal delayed effect and the diffusion operator, which enables us to show the permanence of the equation with respect to the compact open topology. We then employ standard dynamical system arguments to establish the global attractivity of the nontrivial equilibrium. The main results are illustrated by the diffusive Nicholson's blowfly equation and the diffusive Mackey-Glass equation.

Community-Based Eco-Education: Sound Ecology and Effective Education.

ERIC Educational Resources Information Center

Niesenbaum, Richard A.; Gorka, Barbara

2001-01-01

Reports on the development of a college-level eco-educational course that attempts to capitalize on the ecological and educational strengths of ecotourism by establishing a partnership with a local community. Makes suggestions for establishing community partnerships for effective international eco-educational program development. (Contains 15…

Young Children’s Developmental Ecologies and Kindergarten Readiness

PubMed Central

Mollborn, Stefanie

2016-01-01

Children enter the crucial transition to school with sociodemographic disparities firmly established. Domain-specific research (e.g., on poverty and family structure) has shed light on these disparities, but we need broader operationalizations of children’s environments to explain them. Building on existing theory, this study articulates the concept of developmental ecology—those interrelated features of a child’s proximal environment that shape development and health. Developmental ecology links structural and demographic factors with interactional, psychological, and genetic factors. Using the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B), this study conducts latent class analyses to identify how 41 factors from three domains—namely, household resources, health risks, and ecological changes—cluster within children as four overarching developmental ecologies. Because it documents how numerous factors co-occur within children, this method allows an approximation of their lived environments. Findings illuminate powerful relationships between race/ethnicity, parental age, socioeconomic background, and nativity and a child’s developmental ecology, as well as associations between developmental ecology and kindergarten cognition, behavior, and health. Developmental ecology represents a major pathway through which demographic characteristics shape school readiness. Because specific factors have different implications depending on the ecologies in which they are embedded, findings support the usefulness of a broad ecological approach. PMID:27873222

High-precision half-life measurements of the T =1 /2 mirror β decays 17F and 33Cl

NASA Astrophysics Data System (ADS)

Grinyer, J.; Grinyer, G. F.; Babo, M.; Bouzomita, H.; Chauveau, P.; Delahaye, P.; Dubois, M.; Frigot, R.; Jardin, P.; Leboucher, C.; Maunoury, L.; Seiffert, C.; Thomas, J. C.; Traykov, E.

2015-10-01

Background: Measurements of the f t values for T =1 /2 mirror β+ decays offer a method to test the conserved vector current hypothesis and to determine Vud, the up-down matrix element of the Cabibbo-Kobayashi-Maskawa matrix. In most mirror decays used for these tests, uncertainties in the f t values are dominated by the uncertainties in the half-lives. Purpose: Two precision half-life measurements were performed for the T =1 /2 β+ emitters, 17F and 33Cl, in order to eliminate the half-life as the leading source of uncertainty in their f t values. Method: Half-lives of 17F and 33Cl were determined using β counting of implanted radioactive ion beam samples on a moving tape transport system at the Système de Production d'Ions Radioactifs Accélérés en Ligne low-energy identification station at the Grand Accélérateur National d'Ions Lourds. Results: The 17F half-life result, 64.347 (35) s, precise to ±0.05 % , is a factor of 5 times more precise than the previous world average. The half-life of 33Cl was determined to be 2.5038 (22) s. The current precision of ±0.09 % is nearly 2 times more precise compared to the previous world average. Conclusions: The precision achieved during the present measurements implies that the half-life no longer dominates the uncertainty of the f t values for both T =1 /2 mirror decays 17F and 33Cl.

Half-life measurement of the medical radioisotope 177Lu produced from the 176Yb(n,γ) reaction

NASA Astrophysics Data System (ADS)

Ferreira, K. M.; Collins, S. M.; Fenwick, A. J.

2017-09-01

177Lu is a medium energy beta-emitter commonly used in Nuclear Medicine for radiotherapeutic applications. In this work, the half-life of 177Lu has been measured using a re-entrant ionisation chamber over a period of 82 days (approximately 12 half-lives). Unlike the majority of previous studies, the material used in this work was produced via the 176Yb(n,γ)177Yb reaction followed by the β-decay to 177Lu, producing insignificant quantities of 177mLu. This has resulted in the most precise half-life measurement of 177Lu to date. A half-life of 6.6430 (11) days has been determined. This value is in statistical agreement with the currently recommended half-life of 6.6463 (15) days (z-score = 1.8).

Mesonic enhancement of the weak axial charge and its effect on the half-lives and spectral shapes of first-forbidden J+↔J- decays

NASA Astrophysics Data System (ADS)

Kostensalo, Joel; Suhonen, Jouni

2018-06-01

The effects of the enhancement of the axial-charge matrix element γ5 were studied in medium heavy and heavy nuclei for first-forbidden J+ ↔J- decay transitions using the nuclear shell model. Noticeable dependence on the enhancement ɛMEC of the axial-charge matrix element, as well as on the value of the axial-vector coupling constant gA was found in the spectral shapes of 93Y, 95Sr, and 97Y. The importance of the spectrum of 138Cs in the determination of gA is discussed. Half-life analyses in the A ≈ 95 and A ≈ 135 regions were done, and consistent results gA ≈ 0.90, 0.75, and 0.65, corresponding to the three enhancement scenarios ɛMEC = 1.4, 1.7, and 2.0, were obtained. Connection to the reactor-antineutrino anomaly is pointed out.

Interference effects in phased beam tracing using exact half-space solutions.

PubMed

Boucher, Matthew A; Pluymers, Bert; Desmet, Wim

2016-12-01

Geometrical acoustics provides a correct solution to the wave equation for rectangular rooms with rigid boundaries and is an accurate approximation at high frequencies with nearly hard walls. When interference effects are important, phased geometrical acoustics is employed in order to account for phase shifts due to propagation and reflection. Error increases, however, with more absorption, complex impedance values, grazing incidence, smaller volumes and lower frequencies. Replacing the plane wave reflection coefficient with a spherical one reduces the error but results in slower convergence. Frequency-dependent stopping criteria are then applied to avoid calculating higher order reflections for frequencies that have already converged. Exact half-space solutions are used to derive two additional spherical wave reflection coefficients: (i) the Sommerfeld integral, consisting of a plane wave decomposition of a point source and (ii) a line of image sources located at complex coordinates. Phased beam tracing using exact half-space solutions agrees well with the finite element method for rectangular rooms with absorbing boundaries, at low frequencies and for rooms with different aspect ratios. Results are accurate even for long source-to-receiver distances. Finally, the crossover frequency between the plane and spherical wave reflection coefficients is discussed.

Man in the Living Environment. A Report on Global Ecological Problems.

ERIC Educational Resources Information Center

Inger, Robert F.; And Others

The findings of four groups of ecologists are synthesized in chapter I of this report on global ecological problems prepared as a data base for the United Nations Conference on the Human Environment. The other chapters contain the reports of each group. In "Cycles of Elements" the biologically important elements, phosphorus, sulfur, and nitrogen,…

Pre-Service Science Teachers' Views of the Ecological Footprint: The Starting-Points of Sustainable Living

ERIC Educational Resources Information Center

Keles, Ozgul; Aydogdu, Mustafa

2010-01-01

In this study, pre-service science teachers' opinions about the concept of the ecological footprint were investigated before and after activities about sustainable life and their ecological footprints were calculated. A total of 49 pre-service science teachers (31 male, 18 female) who attend third class in the science education department…

[Effects of land use structure change on regional ecological health--taking Shapingba County as an example].

PubMed

Wang, Cheng; Wei, Chaofu; Gao, Ming; Luo, Guanglian; Jiang, Wei

2005-12-01

Land resource is the carrier for the exchange of matter, energy and information flows, while the change velocity and the intensity of land use has strong effects on the ecological processes such as matter circulation, energy flow, and biologic diversity. Land use structure change will alter the type, area, and spatial distribution of ecosystem, and in the meantime, result in the changes of regional ecological health. Employing the principles and methods of landscape ecology, and through endowing relative ecological value to land use type, this paper analyzed the charaeteristics of recent 10 years land use change in Shapingba County of Chongqing, and discussed the effects of land use change on regional ecological health, aimed to provide scientific references for land use planning and sustainable land resource utilization. The results indicated that transformation often occurred among different land use types, and the land use structure in each transformation phase differed quite obviously. Under different land use structure, there was a great disparity in relative ecological value of sub-ecosystems, which played various roles in regional ecological health. In general, the regional relative ecological value embodied both increase and decrease. In the future, the relative ecological value of sub-ecosystem would represent three tendencies, i.e., increase first and decrease then, continuous decrease, and continuous increase. The situation of regional ecological health would gradually become better.

Ecology and management of tansy ragwort (Senecio jacobaea L.)

Treesearch

Jim Jacobs; Sharlene Sing

2009-01-01

Tansy ragwort, a member of the Asteraceae taxonomic family, is a large biennial or short-lived perennial herb native to and widespread throughout Europe and Asia. Stems can grow to a height of 5.5 feet (1.75 meters), with the lower half simple and the upper half many-branched at the inflorescence. Reproductive stems produce up to 2,500 bright golden-yellow flowers....

EVOLUTIONARY AND ECOLOGICAL EFFECTS OF MULTIGENERATIONAL EXPOSURES TO ANTHROPOGENIC STRESSORS

EPA Science Inventory

Biological and ecological responses to stress are dictated by duration and frequency, as well as instantaneous magnitude. Conditional compensatory responses at the physiological and behavioral levels, referred to as ?acclimation', may mitigate effects on individuals experiencing ...

Ecological divergence and talar morphology in gorillas.

PubMed

Dunn, Rachel H; Tocheri, Matthew W; Orr, Caley M; Jungers, William L

2014-04-01

Gorillas occupy a variety of habitats from the west coast to eastern central Africa. These habitats differ considerably in altitude, which has a pronounced effect on forest ecology. Although all gorillas are obligate terrestrial knuckle-walking quadrupeds, those that live in lowland habitats eat fruits and climb more often than do those living in highland habitats. Here we test the hypothesis that gorilla talus morphology falls along a morphocline that tracks locomotor function related to a more inverted or everted foot set. This proposed morphocline predicts that gorillas living in lowland habitats may have a talocrural joint configured to facilitate a more medially oriented foot during climbing, suggesting that they may be more adaptively committed to arboreality than gorillas living in highland habitats. To quantify the relative set of the foot in gorillas, we chose two three-dimensional measurements of the talocrural joint: mediolateral curvature of the trochlea and relative surface area of the lateral malleolus. Our results show that, in comparison to their eastern counterparts, western gorillas have talar features that reflect a more medially directed sole of the foot. This morphology likely facilitates foot placement in a wider range of positions and minimization of shearing stresses across the joint when the foot is loaded on more curved or vertically oriented substrates as occurs during climbing and other arboreal behaviors. In contrast, eastern gorilla talar morphology is consistent with habitual placement of the foot with the sole directed more inferiorly, suggesting more effective loading during plantigrade push-off on terrestrial substrates. Copyright © 2013 Wiley Periodicals, Inc.

Self-Recognition in Live Videos by Young Children: Does Video Training Help?

ERIC Educational Resources Information Center

Demir, Defne; Skouteris, Helen

2010-01-01

The overall aim of the experiment reported here was to establish whether self-recognition in live video can be facilitated when live video training is provided to children aged 2-2.5 years. While the majority of children failed the test of live self-recognition prior to video training, more than half exhibited live self-recognition post video…

Reasons for living, social support, and Afrocentric worldview: assessing buffering factors related to Black Americans' suicidal behavior.

PubMed

Wang, Mei-Chuan; Joel Wong, Y; Tran, Kimberly K; Nyutu, Pius N; Spears, Angela

2013-01-01

This study utilized an ecological framework to explore the role of 4 culturally relevant protective factors-reasons for living, Afrocentric worldview, family support, and friend support-in protecting Black American college students from suicidal behavior. Participants were 289 Black American college students. We hypothesized that these 4 culturally relevant factors would exert indirect protective effects on suicidal behavior through their association with reduced depressive symptoms. Results indicated that reasons for living, perceived supportive behaviors from family, and Afrocentric worldview exerted indirect protective effects on suicidal behaviors through their negative associations with depressive symptoms. The mediation effect from friend support to depression and suicidal behavior was not significant.

Living Labs: overview of ecological approaches for health promotion and rehabilitation.

PubMed

Korman, M; Weiss, P L; Kizony, R

2016-01-01

The term "Living Lab" was coined to reflect the use of sensors to monitor human behavior in real life environments. Until recently such measurements had been feasible only within experimental laboratory settings. The objective of this paper is to highlight research on health care sensing and monitoring devices that enable direct, objective and accurate capture of real-world functioning. Selected articles exemplifying the key technologies that allow monitoring of the motor-cognitive activity of persons with disabilities during naturally occurring daily experiences in real-life settings are discussed in terms of (1) the ways in which the Living Lab approach has been used to date, (2) limitations related to clinical assessment in rehabilitation settings and (3) three categories of the instruments most commonly used for this purpose: personal technologies, ambient technologies and external assistive systems. Technology's most important influences on clinical practice and rehabilitation are in a shift from laboratory-based to field-centered research and a transition between in-clinic performance to daily life activities. Numerous applications show its potential for real-time clinical assessment. Current technological solutions that may provide clinicians with objective, unobtrusive measurements of health and function, as well as tools that support rehabilitation on an individual basis in natural environments provide an important asset to standard clinical measures. Until recently objective clinical assessment could not be readily performed in a client's daily functional environment. Novel technologies enable health care sensing and monitoring devices that enable direct, objective and accurate capture of real-world functioning. Such technologies are referred to as a "Living Lab" approach since they enable the capture of objective and non-obtrusive data that clinicians can use to assess performance. Research and development in this field help clinicians support maintain

Validation of Different Combination of Three Reversing Half-Hitches Alternating Posts (RHAPs) Effects on Arthroscopic Knot Integrity.

PubMed

Chong, Alexander Cm; Prohaska, Daniel J; Bye, Brian P

2017-05-01

With arthroscopic techniques being used, the importance of knot tying has been examined. Previous literature has examined the use of reversing half-hitches on alternating posts (RHAPs) on knot security. Separately, there has been research regarding different suture materials commonly used in the operating room. The specific aim of this study was to validate the effect of different stacked half-hitch configuration and different braided suture materials on arthroscopic knot integrity. Three different suture materials tied with five different RHAPs in arthroscopic knots were compared. A single load-to-failure test was performed and the mean ultimate clinical failure load was obtained. Significant knot holding strength improvement was found when one half-hitch was reversed as compared to baseline knot. When two of the half-hitches were reversed, there was a greater improvement with all knots having a mean ultimate clinical failure load greater than 150 newtons (N). Comparison of the suture materials demonstrated a higher mean ultimate clinical failure load when Force Fiber ® was used and at least one half-hitch was reversed. Knots tied with either Force Fiber ® or Orthocord ® showed 0% chance of knot slippage while knots tied with FiberWire ® or braided fishing line had about 10 and 30% knot slippage chances, respectively. A significant effect was observed in regards to both stacked half-hitch configuration and suture materials used on knot loop and knot security. Caution should be used with tying three RHAPs in arthroscopic surgery, particularly with a standard knot pusher and arthroscopic cannulas. The findings of this study indicated the importance of three RHAPs in performing arthroscopic knot tying and provided evidence regarding discrepancies of maximum clinical failure loads observed between orthopaedic surgeons, thereby leading to better surgical outcomes in the future.

External radiation exposure, excretion, and effective half-life in 177Lu-PSMA-targeted therapies.

PubMed

Kurth, J; Krause, B J; Schwarzenböck, S M; Stegger, L; Schäfers, M; Rahbar, K

2018-04-12

Prostate-specific membrane antigen (PSMA)-targeted therapy with 177 Lu-PSMA-617 is a therapeutic option for patients with metastatic castration-resistant prostate cancer (mCRPC). To optimize the therapy procedure, it is necessary to determine relevant parameters to define radiation protection and safety necessities. Therefore, this study aimed at estimating the ambient radiation exposure received by the patient. Moreover, the excreted activity was quantified. In total, 50 patients with mCRPC and treated with 177 Lu-PSMA-617 (mean administered activity 6.3 ± 0.5 GBq) were retrospectively included in a bi-centric study. Whole-body dose rates were measured at a distance of 2 m at various time points after application of 177 Lu-PSMA-617, and effective half-lives for different time points were calculated and compared. Radiation exposure to the public was approximated using the dose integral. For the estimation of the excreted activity, whole body measurements of 25 patients were performed at 7 time points. Unbound 177 Lu-PSMA-617 was rapidly cleared from the body. After 4 h, approximately 50% and, after 12 h, approximately 70% of the administered activity were excreted, primarily via urine. The mean dose rates were the following: 3.6 ± 0.7 μSv/h at 2 h p. i., 1.6 ± 0.6 μSv/h at 24 h, 1.1 ± 0.5 μSv/h at 48 h, and 0.7 ± 0.4 μSv/h at 72 h. The mean effective half-life of the cohort was 40.5 ± 9.6 h (min 21.7 h; max 85.7 h). The maximum dose to individual members of the public per treatment cycle was ~ 250 ± 55 μSv when the patient was discharged from the clinic after 48 h and ~ 190 ± 36 μSv when the patient was discharged after 72 h. In terms of the radiation exposure to the public, 177 Lu-PSMA is a safe option of radionuclide therapy. As usually four (sometimes more) cycles of the therapy are performed, it must be conducted in a way that ensures that applicable legal requirements can be followed. In

Environmental effects of increased coal utilization: ecological effects of gaseous emissions from coal combustion.

PubMed Central

Glass, N R

1979-01-01

This report is limited to an evaluation of the ecological and environmental effects of gaseous emissions and aerosols of various types which result from coal combustion. It deals with NOx, SOx, fine particulate, photochemical oxidant and acid precipitation as these pollutants affect natural and managed resources and ecosystems. Also, synergistic effects involving two or more pollutants are evaluated as well as ecosystem level effects of gaseous pollutants. There is a brief summary of the effects on materials and atmospheric visibility of increased coal combustion. The economic implications of ecological effects are identified to the extent they can be determined within acceptable limits. Aquatic and terrestrial effects are distinguished where the pollutants in question are clearly problems in both media. At present, acid precipitation is most abundant in the north central and northeastern states. Total SOx and NOx emissions are projected to remain high in these regions while increasing relatively more in the western than in the eastern regions of the country. A variety of ecological processes are affected and altered by air pollution. Such processes include community succession and retrogression, nutrient biogeochemical cycling, photosynthetic activity, primary and secondary productivity, species diversity and community stability. Estimates of the non health-related cost of air pollutants range from several hundred million dollars to $1.7 billion dollars per year. In general, these estimates include only those relatively easily measured considerations such as the known losses to cultivate crops from acute air pollution episodes or the cost of frequent repainting required as a result of air pollution. No substantial nationwide estimates of losses to forest productivity, natural ecosystem productivity which is tapped by domestic grazing animals and wildlife, and other significant dollar losses are available. PMID:44247

An overview of the ecological half-life of the 137Cs radioisotope and a determination of radioactivity levels in sediment samples after Chernobyl in the Eastern Black Sea, Turkey

NASA Astrophysics Data System (ADS)

Baltas, Hasan; Sirin, Murat; Dalgic, Goktug; Cevik, Ugur

2018-01-01

A study which determined the activity concentration of 137Cs in sediments contaminated by effluents from the Chernobyl accident which had collected along the coast of the Eastern Black Sea region in Turkey was carried out in 1993. Marine sediment samples were collected in 2015 from the same fifteen sampling points, and the activity concentrations of 226Ra, 232Th, 40K and 137Cs were determined for the sediment samples. The activity concentrations ranged from 10.94-25.95, 12.14-33.05, 265.74-459.89 and 2.08-37.45 Bq kg- 1 for 226Ra, 232Th, 40K and 137Cs respectively. The results showed that there was a steep decline in 137Cs within the sediment at most of the sampling sites from the Eastern Black Sea region during the 22-year period, except for two sites at which the measured levels were much higher. This may be the result of the combined effects of radioactive contaminant entry into this area from rivers, environmental changes and nuclear testing between 1993 and 2015. Furthermore, the ecological half-life (EHL) of the 137Cs radionuclide was estimated for the sediment samples, and radiological hazard parameters such as the absorbed dose rate in air (D), the annual effective dose equivalent (AEDE) and the excess lifetime cancer risk (ELCR) were calculated and compared with the international recommended values. It was shown that these sediments do not present any significant health risk for humans in this area.

Population Health, Ethnicity and Rate of Living Donor Kidney Transplantation.

PubMed

Reed, Rhiannon D; Sawinski, Deirdre; Shelton, Brittany A; MacLennan, Paul A; Hanaway, Michael; Kumar, Vineeta; Long, Dustin; Gaston, Robert S; Kilgore, Meredith L; Julian, Bruce A; Lewis, Cora E; Locke, Jayme E

2018-05-22

Living donor kidney transplantation has declined in the United States since 2004, but the relationship between population characteristics and rate of living donation is unknown. The goal of our study was to use data on general population health and socioeconomic status to investigate the association with living donation. This cross-sectional, ecological study used population health and socioeconomic status data from the CDC Behavioral Risk Factor Surveillance System (BRFSS) to investigate the association with living donation. Transplant centers performing ≥ 10 kidney transplants reported to the Scientific Registry of Transplant Recipients in 2015 were included. Center rate of living donation was defined as the proportion of all kidney transplants performed at a center that were from living donors. In a linear mixed effects model, a composite index of health and socioeconomic status factors was negatively associated with living donation, with a rate of living donation that was on average 7.3 percentage points lower among centers in areas with more comorbid disease and poorer socioeconomic status (95% CI: -12.2 to -2.3, p=0.004). Transplant centers in areas with higher prevalence of minorities had a rate of living donation that was 7.1 percentage points lower than centers with fewer minorities (95% CI: -11.8 to -2.3, p=0.004). Center level variation in living donation was associated with population characteristics and minority prevalence. Further examination of these factors in the context of patient and center-level barriers to living donation is warranted.

FORUM: Effective management of ecological resilience – are we there yet?

USGS Publications Warehouse

Spears, Bryan M.; Ives, Stephen C.; Angeler, David G.; Allen, Craig R.; Birk, Sebastian; Carvalho, Laurence; Cavers, Stephen; Daunt, Francis; Morton, R. Daniel; Pocock, Michael J. O.; Rhodes, Glenn; Thackeray, Stephen J.

2015-01-01

Ecological resilience is developing into a credible paradigm for policy development and environmental management for preserving natural capital in a rapidly changing world. However, resilience emerges from complex interactions, limiting the translation of theory into practice.Main limitations include the following: (i) difficulty in quantification and detection of changes in ecological resilience, (ii) a lack of empirical evidence to support preventative or proactive management and (iii) difficulties in managing processes operating across socio-ecological systems that vary in space and time.We highlight recent research with the potential to address these limitations including new and/or improved indicators of resilience and tools to assess scale as a driver of resilience.Synthesis and applications. Effective resilience-based management must be adaptive in nature. To support this, we propose an operational model using resilience-based iterative management actions operating across scales.

First evidence of dengue infection in domestic dogs living in different ecological settings in Thailand.

PubMed

Thongyuan, Suporn; Kittayapong, Pattamaporn

2017-01-01

Dengue is a vector-borne disease transmitted by Aedes mosquitoes. It is considered an important public health problem in many countries worldwide. However, only a few studies have been conducted on primates and domestic animals that could potentially be a reservoir of dengue viruses. Since domestic dogs share both habitats and vectors with humans, this study aimed to investigate whether domestic dogs living in different ecological settings in dengue endemic areas in Thailand could be naturally infected with dengue viruses. Serum samples were collected from domestic dogs in three different ecological settings of Thailand: urban dengue endemic areas of Nakhon Sawan Province; rubber plantation areas of Rayong Province; and Koh Chang, an island tourist spot of Trat Province. These samples were screened for dengue viral genome by using semi-nested RT-PCR. Positive samples were then inoculated in mosquito and dog cell lines for virus isolation. Supernatant collected from cell culture was tested for the presence of dengue viral genome by semi-nested RT-PCR, then double-strand DNA products were double-pass custom-sequenced. Partial nucleotide sequences were aligned with the sequences already recorded in GenBank, and a phylogenetic tree was constructed. In the urban setting, 632 domestic dog serum samples were screened for dengue virus genome by RT-PCR, and six samples (0.95%) tested positive for dengue virus. Four out of six dengue viruses from positive samples were successfully isolated. Dengue virus serotype 2 and serotype 3 were found to have circulated in domestic dog populations. One of 153 samples (0.65%) collected from the rubber plantation area showed a PCR-positive result, and dengue serotype 3 was successfully isolated. Partial gene phylogeny revealed that the isolated dengue viruses were closely related to those strains circulating in human populations. None of the 71 samples collected from the island tourist spot showed a positive result. We concluded that

A synthesis of the theory of silencing the self and the social ecological model: understanding gender, race, and depression in African American women living with HIV infection.

PubMed

Lanier, Latrona; DeMarco, Rosanna

2015-03-01

The challenges that face African American women living with HIV are immense. African American women continue to be disproportionately infected and affected by this chronic and life-threatening infection in a complex context of individual experience, interactions with the environment, formal and informal support systems, and cultural belief systems. This article identifies the Theory of Silencing the Self (STS) and a widely known model, the Social Ecological Model (SEM), as a synthesized explanatory framework in helping nurses understand how to address research questions and clinical care that is congruent with the experience of African American women living with HIV infection. In synthesizing the components of these two frameworks, an explanation of the relationship between disempowerment and depression in this population will be uncovered as a key component to making relationships at the individual, family, and community level better. Helping African American women living with HIV infection to explore and address how choosing to be silent across their life systems will advance healthcare adherence as we currently know it to improved self-management of a chronic, gender-specific, culturally-bound experience of depression.

Molecules, morphology, and ecology indicate a recent, amphibious ancestry for echidnas.

PubMed

Phillips, Matthew J; Bennett, Thomas H; Lee, Michael S Y

2009-10-06

The semiaquatic platypus and terrestrial echidnas (spiny anteaters) are the only living egg-laying mammals (monotremes). The fossil record has provided few clues as to their origins and the evolution of their ecological specializations; however, recent reassignment of the Early Cretaceous Teinolophos and Steropodon to the platypus lineage implies that platypuses and echidnas diverged >112.5 million years ago, reinforcing the notion of monotremes as living fossils. This placement is based primarily on characters related to a single feature, the enlarged mandibular canal, which supplies blood vessels and dense electrosensory receptors to the platypus bill. Our reevaluation of the morphological data instead groups platypus and echidnas to the exclusion of Teinolophos and Steropodon and suggests that an enlarged mandibular canal is ancestral for monotremes (partly reversed in echidnas, in association with general mandibular reduction). A multigene evaluation of the echidna-platypus divergence using both a relaxed molecular clock and direct fossil calibrations reveals a recent split of 19-48 million years ago. Platypus-like monotremes (Monotrematum) predate this divergence, indicating that echidnas had aquatically foraging ancestors that reinvaded terrestrial ecosystems. This ecological shift and the associated radiation of echidnas represent a recent expansion of niche space despite potential competition from marsupials. Monotremes might have survived the invasion of marsupials into Australasia by exploiting ecological niches in which marsupials are restricted by their reproductive mode. Morphology, ecology, and molecular biology together indicate that Teinolophos and Steropodon are basal monotremes rather than platypus relatives, and that living monotremes are a relatively recent radiation.

[Ecological carrying capacity and Chongming Island's ecological construction].

PubMed

Wang, Kaiyun; Zou, Chunjing; Kong, Zhenghong; Wang, Tianhou; Chen, Xiaoyong

2005-12-01

This paper overviewed the goals of Chongming Island's ecological construction and its background, analyzed the current eco-economic status and constraints of the Island, and put forward some scientific issues on its ecological construction. It was suggested that for the resources-saving and sustainable development of the Island, the researches on its ecological construction should be based on its ecological carrying capacity, fully take the regional characteristics into consideration, and refer the successful development modes at home and abroad. The carrying capacity study should ground on systemic and dynamic views, give a thorough evaluation of the Island's present carrying capacity, simulate its possible changes, and forecast its demands and risks. Operable countermeasures to promote the Island's carrying capacity should be worked out, new industry structure, population scale, and optimized distribution projects conforming to regional carrying capacity should be formulated, and effective ecological security alarming and control system should be built, with the aim of providing suggestions and strategic evidences for the decision-making of economic development and sustainable environmental resources use of the region.

EPA ’s ECOLOGICAL MODELS FOR INTEGRATED WATERSHED MANAGEMENT

EPA Science Inventory

Aquatic ecological populations and communities are affected by the nature and quality of the water in which they live. Specific factors that affect instream biota include chemical variables, biotic interactions, energy source, flow regime, and habitat structure. As watershed mana...

The Effects of "Live Virtual Classroom" on Students' Achievement and Students' Opinions about "Live Virtual Classroom" at Distance Education

ERIC Educational Resources Information Center

Yilmaz, Ozgur

2015-01-01

This study was performed to investigate the effects of live virtual classroom on students' achievement and to determine students' opinions about the live virtual physics classroom at distance learning. 63 second-year Distance Computer Education & Instructional Technology students enrolled in this study. At the live virtual physics classroom,…

Associations of Affective Responses During Free-Living Physical Activity and Future Physical Activity Levels: an Ecological Momentary Assessment Study.

PubMed

Liao, Yue; Chou, Chih-Ping; Huh, Jimi; Leventhal, Adam; Dunton, Genevieve

2017-08-01

Affective response during physical activity may influence motivation to perform future physical activity behavior. However, affective response during physical activity is often assessed under controlled laboratory conditions. The current study used ecological momentary assessment (EMA) to capture affective responses during free-living physical activity performed by adults, and determined whether these affective responses predict future moderate-to-vigorous physical activity (MVPA) levels after 6 and 12 months. At baseline, electronic EMA surveys were randomly prompted across 4 days asking about current activities and affective states (e.g., happy, stressed, energetic, tired). Affective response during physical activity was operationalized as the level of positive or negative affect reported when concurrent physical activity (e.g., exercise or sports) was also reported. Data were available for 82 adults. Future levels of moderate-to-vigorous physical activity (MVPA) were measured using accelerometers, worn for seven consecutive days at 6 and 12 months after the baseline assessment. Feeling more energetic during physical activity was associated with performing more minutes of daily MVPA after both 6 and 12 months. Feeling less negative affect during physical activity was associated with engaging in more daily MVPA minutes after 12 months only. This study demonstrated how EMA can be used to capture affective responses during free-living physical activity. Results found that feelings more energetic and less negative during physical activity were associated with more future physical activity, suggesting that positive emotional benefits may reinforce behavior.

The Welfare Implications of Using Exotic Tortoises as Ecological Replacements

PubMed Central

Griffiths, Christine J.; Zuël, Nicolas; Tatayah, Vikash; Jones, Carl G.; Griffiths, Owen; Harris, Stephen

2012-01-01

Background Ecological replacement involves the introduction of non-native species to habitats beyond their historical range, a factor identified as increasing the risk of failure for translocations. Yet the effectiveness and success of ecological replacement rely in part on the ability of translocatees to adapt, survive and potentially reproduce in a novel environment. We discuss the welfare aspects of translocating captive-reared non-native tortoises, Aldabrachelys gigantea and Astrochelys radiata, to two offshore Mauritian islands, and the costs and success of the projects to date. Methodology/Principal Findings Because tortoises are long-lived, late-maturing reptiles, we assessed the progress of the translocation by monitoring the survival, health, growth, and breeding by the founders. Between 2000 and 2011, a total of 26 A. gigantea were introduced to Ile aux Aigrettes, and in 2007 twelve sexually immature A. gigantea and twelve male A. radiata were introduced to Round Island, Mauritius. Annual mortality rates were low, with most animals either maintaining or gaining weight. A minimum of 529 hatchlings were produced on Ile aux Aigrettes in 11 years; there was no potential for breeding on Round Island. Project costs were low. We attribute the success of these introductions to the tortoises’ generalist diet, habitat requirements, and innate behaviour. Conclusions/Significance Feasibility analyses for ecological replacement and assisted colonisation projects should consider the candidate species’ welfare during translocation and in its recipient environment. Our study provides a useful model for how this should be done. In addition to serving as ecological replacements for extinct Mauritian tortoises, we found that releasing small numbers of captive-reared A. gigantea and A. radiata is cost-effective and successful in the short term. The ability to release small numbers of animals is a particularly important attribute for ecological replacement projects since

The welfare implications of using exotic tortoises as ecological replacements.

PubMed

Griffiths, Christine J; Zuël, Nicolas; Tatayah, Vikash; Jones, Carl G; Griffiths, Owen; Harris, Stephen

2012-01-01

Ecological replacement involves the introduction of non-native species to habitats beyond their historical range, a factor identified as increasing the risk of failure for translocations. Yet the effectiveness and success of ecological replacement rely in part on the ability of translocatees to adapt, survive and potentially reproduce in a novel environment. We discuss the welfare aspects of translocating captive-reared non-native tortoises, Aldabrachelys gigantea and Astrochelys radiata, to two offshore Mauritian islands, and the costs and success of the projects to date. Because tortoises are long-lived, late-maturing reptiles, we assessed the progress of the translocation by monitoring the survival, health, growth, and breeding by the founders. Between 2000 and 2011, a total of 26 A. gigantea were introduced to Ile aux Aigrettes, and in 2007 twelve sexually immature A. gigantea and twelve male A. radiata were introduced to Round Island, Mauritius. Annual mortality rates were low, with most animals either maintaining or gaining weight. A minimum of 529 hatchlings were produced on Ile aux Aigrettes in 11 years; there was no potential for breeding on Round Island. Project costs were low. We attribute the success of these introductions to the tortoises' generalist diet, habitat requirements, and innate behaviour. Feasibility analyses for ecological replacement and assisted colonisation projects should consider the candidate species' welfare during translocation and in its recipient environment. Our study provides a useful model for how this should be done. In addition to serving as ecological replacements for extinct Mauritian tortoises, we found that releasing small numbers of captive-reared A. gigantea and A. radiata is cost-effective and successful in the short term. The ability to release small numbers of animals is a particularly important attribute for ecological replacement projects since it reduces the potential risk and controversy associated with

Cultivating the Social, Emotional, and Inner Lives of Children and Teachers

ERIC Educational Resources Information Center

Lantieri, Linda

2012-01-01

Adults often feel the pressures of today's fast-paced world and think back longingly to a time when their daily lives were a lot less hectic. One third of the respondents in one study report that they are living with "extreme stress" and almost half feel that the level of stress in their lives has increased over the past five years. Children are…

Eawag-Soil in enviPath: a new resource for exploring regulatory pesticide soil biodegradation pathways and half-life data.

PubMed

Latino, Diogo A R S; Wicker, Jörg; Gütlein, Martin; Schmid, Emanuel; Kramer, Stefan; Fenner, Kathrin

2017-03-22

Developing models for the prediction of microbial biotransformation pathways and half-lives of trace organic contaminants in different environments requires as training data easily accessible and sufficiently large collections of respective biotransformation data that are annotated with metadata on study conditions. Here, we present the Eawag-Soil package, a public database that has been developed to contain all freely accessible regulatory data on pesticide degradation in laboratory soil simulation studies for pesticides registered in the EU (282 degradation pathways, 1535 reactions, 1619 compounds and 4716 biotransformation half-life values with corresponding metadata on study conditions). We provide a thorough description of this novel data resource, and discuss important features of the pesticide soil degradation data that are relevant for model development. Most notably, the variability of half-life values for individual compounds is large and only about one order of magnitude lower than the entire range of median half-life values spanned by all compounds, demonstrating the need to consider study conditions in the development of more accurate models for biotransformation prediction. We further show how the data can be used to find missing rules relevant for predicting soil biotransformation pathways. From this analysis, eight examples of reaction types were presented that should trigger the formulation of new biotransformation rules, e.g., Ar-OH methylation, or the extension of existing rules, e.g., hydroxylation in aliphatic rings. The data were also used to exemplarily explore the dependence of half-lives of different amide pesticides on chemical class and experimental parameters. This analysis highlighted the value of considering initial transformation reactions for the development of meaningful quantitative-structure biotransformation relationships (QSBR), which is a novel opportunity offered by the simultaneous encoding of transformation reactions and

A METHOD TO INCORPORATE ECOLOGY INTO RESIDENCE TIME OF CHEMICALS IN EMBAYMENTS: LOCAL EFFECT TIME

EPA Science Inventory

Residence times are classically defined by the physical and chemical aspects of water bodies rather than by their ecological implications. Therefore, a more clear and direct connection between the residence times and ecological effects is necessary to quantitatively relate these ...

Cumulative ecological and socioeconomic effects of forest policies in coastal Oregon.

Treesearch

T.A. Spies; K.N. Johnson; K.M. Burnett; J.L. Ohmann; B.C. McComb; G.H. Reeves; P. Bettinger; J.D. Kline; B. Garber-Yonts

2007-01-01

Forest biodiversity policies in multiownership landscapes are typically developed in an uncoordinated fashion with little consideration of their interactions or possible unintended cumulative effects. We conducted an assessment of some of the ecological and socioeconomic effects of recently enacted forest management policies in the 2.3-million-ha Coast Range...

Effects of plants containing secondary compounds and plant oils on rumen fermentation and ecology.

PubMed

Wanapat, Metha; Kongmun, Pongthon; Poungchompu, Onanong; Cherdthong, Anusorn; Khejornsart, Pichad; Pilajun, Ruangyote; Kaenpakdee, Sujittra

2012-03-01

A number of experiments have been conducted to investigate effects of tropical plants containing condensed tannins and/or saponins present in tropical plants and some plant oils on rumen fermentation and ecology in ruminants. Based on both in vitro and in vivo trials, the results revealed important effects on rumen microorganisms and fermentation including methane production. Incorporation and/or supplementation of these plants containing secondary metabolites have potential for improving rumen ecology and subsequently productivity in ruminants.

Community-level demographic consequences of urbanization: an ecological network approach.

PubMed

Rodewald, Amanda D; Rohr, Rudolf P; Fortuna, Miguel A; Bascompte, Jordi

2014-11-01

Ecological networks are known to influence ecosystem attributes, but we poorly understand how interspecific network structure affect population demography of multiple species, particularly for vertebrates. Establishing the link between network structure and demography is at the crux of being able to use networks to understand population dynamics and to inform conservation. We addressed the critical but unanswered question, does network structure explain demographic consequences of urbanization? We studied 141 ecological networks representing interactions between plants and nesting birds in forests across an urbanization gradient in Ohio, USA, from 2001 to 2011. Nest predators were identified by video-recording nests and surveyed from 2004 to 2011. As landscapes urbanized, bird-plant networks were more nested, less compartmentalized and dominated by strong interactions between a few species (i.e. low evenness). Evenness of interaction strengths promoted avian nest survival, and evenness explained demography better than urbanization, level of invasion, numbers of predators or other qualitative network metrics. Highly uneven networks had approximately half the nesting success as the most even networks. Thus, nest survival reflected how urbanization altered species interactions, particularly with respect to how nest placement affected search efficiency of predators. The demographic effects of urbanization were not direct, but were filtered through bird-plant networks. This study illustrates how network structure can influence demography at the community level and further, that knowledge of species interactions and a network approach may be requisite to understanding demographic responses to environmental change. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Potential Biological and Ecological Effects of Flickering Artificial Light

PubMed Central

Inger, Richard; Bennie, Jonathan; Davies, Thomas W.; Gaston, Kevin J.

2014-01-01

Organisms have evolved under stable natural lighting regimes, employing cues from these to govern key ecological processes. However, the extent and density of artificial lighting within the environment has increased recently, causing widespread alteration of these regimes. Indeed, night-time electric lighting is known significantly to disrupt phenology, behaviour, and reproductive success, and thence community composition and ecosystem functioning. Until now, most attention has focussed on effects of the occurrence, timing, and spectral composition of artificial lighting. Little considered is that many types of lamp do not produce a constant stream of light but a series of pulses. This flickering light has been shown to have detrimental effects in humans and other species. Whether a species is likely to be affected will largely be determined by its visual temporal resolution, measured as the critical fusion frequency. That is the frequency at which a series of light pulses are perceived as a constant stream. Here we use the largest collation to date of critical fusion frequencies, across a broad range of taxa, to demonstrate that a significant proportion of species can detect such flicker in widely used lamps. Flickering artificial light thus has marked potential to produce ecological effects that have not previously been considered. PMID:24874801

Online Farsi digit recognition using their upper half structure

NASA Astrophysics Data System (ADS)

Ghods, Vahid; Sohrabi, Mohammad Karim

2015-03-01

In this paper, we investigated the efficiency of upper half Farsi numerical digit structure. In other words, half of data (upper half of the digit shapes) was exploited for the recognition of Farsi numerical digits. This method can be used for both offline and online recognition. Half of data is more effective in speed process, data transfer and in this application accuracy. Hidden Markov model (HMM) was used to classify online Farsi digits. Evaluation was performed by TMU dataset. This dataset contains more than 1200 samples of online handwritten Farsi digits. The proposed method yielded more accuracy in recognition rate.

A Case Controlled Examination of the Interpersonal Theory of Suicide in the Second Half of Life.

PubMed

Van Orden, Kimberly A; Smith, Phillip N; Chen, Tian; Conwell, Yeates

2016-07-02

The interpersonal theory of suicide proposes that the most proximal cause of suicide is the combination of thwarted belongingness and perceived burdensomeness coupled with a pre-existing vulnerability of reduced fear of death and increased pain tolerance. This pre-existing vulnerability develops in response to painful and provocative life events. According to the theory, empirically demonstrated risk factors for suicide operate by increasing the likelihood of one or more of the theory's constructs. The current study examined the relations of the major constructs of the interpersonal theory with suicide case status compared to living controls in the second half of life. The current study used a pre-existing psychological autopsy database to compare suicide decedents to living controls 50 years and older. Theory constructs were measured by composite scores of thwarted belongingness, perceived burdensomeness, and painful and provocative experiences using an a priori selection of items comprising each construct. Suicide decedents experienced greater levels of all three of the theory's constructs when examined independently compared to living controls. When examined simultaneously while also controlling for Major Depression, greater perceived burdensomeness and painful and provocative experiences were associated with suicide case status (vs. control). The interpersonal theory is a comprehensive framework that may be useful in understanding risk for death by suicide in the second half of life. Clinical management of suicide risk for adults in the second half of life could include a focus on perceived burdensomeness, as the IPTS proposes that this psychological state is amenable to change via therapeutic intervention.

Continuous leg dyskinesia assessment in Parkinson's disease -clinical validity and ecological effect.

PubMed

Ramsperger, Robert; Meckler, Stefan; Heger, Tanja; van Uem, Janet; Hucker, Svenja; Braatz, Ulrike; Graessner, Holm; Berg, Daniela; Manoli, Yiannos; Serrano, J Artur; Ferreira, Joaquim J; Hobert, Markus A; Maetzler, Walter

2016-05-01

Dyskinesias in Parkinson's disease (PD) patients are a common side effect of long-term dopaminergic therapy and are associated with motor dysfunctions, including gait and balance deficits. Although promising compounds have been developed to treat these symptoms, clinical trials have failed. This failure may, at least partly, be explained by the lack of objective and continuous assessment strategies. This study tested the clinical validity and ecological effect of an algorithm that detects and quantifies dyskinesias of the legs using a single ankle-worn sensor. Twenty-three PD patients (seven with leg dyskinesias) and 13 control subjects were investigated in the lab. Participants performed purposeful daily activity-like tasks while being video-taped. Clinical evaluation was performed using the leg dyskinesia item of the Unified Dyskinesia Rating Scale. The ecological effect of the developed algorithm was investigated in a multi-center, 12-week, home-based sub-study that included three patients with and seven without dyskinesias. In the lab-based sub-study, the sensor-based algorithm exhibited a specificity of 98%, a sensitivity of 85%, and an accuracy of 0.96 for the detection of dyskinesias and a correlation level of 0.61 (p < 0.001) with the clinical severity score. In the home-based sub-study, all patients could be correctly classified regarding the presence or absence of leg dyskinesias, supporting the ecological relevance of the algorithm. This study provides evidence of clinical validity and ecological effect of an algorithm derived from a single sensor on the ankle for detecting leg dyskinesias in PD patients. These results should motivate the investigation of leg dyskinesias in larger studies using wearable sensors. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ancient DNA from marine mammals: studying long-lived species over ecological and evolutionary timescales.

PubMed

Foote, Andrew D; Hofreiter, Michael; Morin, Phillip A

2012-01-20

Marine mammals have long generation times and broad, difficult to sample distributions, which makes inferring evolutionary and demographic changes using field studies of extant populations challenging. However, molecular analyses from sub-fossil or historical materials of marine mammals such as bone, tooth, baleen, skin, fur, whiskers and scrimshaw using ancient DNA (aDNA) approaches provide an opportunity for investigating such changes over evolutionary and ecological timescales. Here, we review the application of aDNA techniques to the study of marine mammals. Most of the studies have focused on detecting changes in genetic diversity following periods of exploitation and environmental change. To date, these studies have shown that even small sample sizes can provide useful information on historical genetic diversity. Ancient DNA has also been used in investigations of changes in distribution and range of marine mammal species; we review these studies and discuss the limitations of such 'presence only' studies. Combining aDNA data with stable isotopes can provide further insights into changes in ecology and we review past studies and suggest future potential applications. We also discuss studies reconstructing inter- and intra-specific phylogenies from aDNA sequences and discuss how aDNA sequences could be used to estimate mutation rates. Finally, we highlight some of the problems of aDNA studies on marine mammals, such as obtaining sufficient sample sizes and calibrating for the marine reservoir effect when radiocarbon-dating such wide-ranging species. Copyright © 2011 Elsevier GmbH. All rights reserved.

Effects of simulated increased gravity on the rate of aging of rats - Implications for the rate of living theory of aging

NASA Technical Reports Server (NTRS)

Economos, A. C.; Ballard, R. C.; Blunden, M.; Miquel, J.; Lindseth, K. A.; Fleming, J.; Philpott, D. E.; Oyama, J.

1982-01-01

It was found that the rate of aging of 17 month old rats which had been exposed to 3.14 times normal gravity in an animal centrifuge for 8 months was larger than that of the controls as determined by the apparently elevated lipofuscin content in heart and kidney, reduced numbers and increased size of mitochondria of heart tissue, and inferior liver mitochondria respiration. Steady-state food intake per day per kg body weight, which is presumably proportional to rate of living or specific basal metabolic expenditure, was found to be about 18 percent higher than in the controls after an initial 2 month adaptation period. Although half of the centrifuged animals lived only a little shorter than the controls (average about 343 vs. 364 days on the average, statistically nonsignificant), the remaining half (longest survivors) lived on the centrifuge an average of 520 days (range 483-572) compared to an average of 574 days (range 502-615) for the controls, computed from the onset of centrifugation, or 11 percent shorter. These findings indicate that a moderate increase of the level of basal metabolism of young adult rats adapted to hypergravity compared to controls in normal gravity is accompanied by a roughly similar increase in the rate of organ aging and reduction of survival, in agreement with Pearl's (1928) rate of living theory of aging, previously experimentally demonstrated only in poikilotherms.

Living Effectively in the 70's.

ERIC Educational Resources Information Center

Alexis I. DuPont School District, Greenville, DE.

GRADES OR AGES: Unspecified. SUBJECT MATTER: Effective living. ORGANIZATION AND PHYSICAL APPEARANCE: Most of the pages are divided into three columns: concept, some activities, and teacher comments. The guide is offset printed and spiral bound with a soft cover. OBJECTIVES AND ACTIVITIES: The guide is divided into eight units: human growth and…

Live load effect in reinforced concrete box culverts under soil fill.

DOT National Transportation Integrated Search

2013-08-01

Live load effects in box culverts generally diminish with soil fill thickness. In addition, the effect of : the live load may be nearly negligible compared to the dead loads when significant fill is placed above the : crown of the culvert. The object...

Half radiofrequency pulse excitation with a dedicated prescan to correct eddy current effect and gradient delay.

PubMed

Abe, Takayuki

2013-03-01

To improve the slice profile of the half radiofrequency (RF) pulse excitation and image quality of ultrashort echo time (UTE) imaging by compensating for an eddy current effect. The dedicated prescan has been developed to measure the phase accumulation due to eddy currents induced by the slice-selective gradient. The prescan measures two one-dimensional excitation k-space profiles, which can be acquired with a readout gradient in the slice-selection direction by changing the polarity of the slice-selective gradient. The time shifts due to the phase accumulation in the excitation k-space were calculated. The time shift compensated for the start time of the slice-selective gradient. The total prescan time was 6-15 s. The slice profile and the UTE image with the half RF pulse excitation were acquired to evaluate the slice selectivity and the image quality. Improved slice selectivity was obtained. The simple method proposed in this paper can eliminate eddy current effect. Good UTE images were obtained. The slice profile of the half RF pulse excitation and the image quality of UTE images have been improved by using a dedicated prescan. This method has a possibility that can improve the image quality of a clinical UTE imaging.

Integration of research infrastructures and ecosystem models toward development of predictive ecology

NASA Astrophysics Data System (ADS)

Luo, Y.; Huang, Y.; Jiang, J.; MA, S.; Saruta, V.; Liang, G.; Hanson, P. J.; Ricciuto, D. M.; Milcu, A.; Roy, J.

2017-12-01

The past two decades have witnessed rapid development in sensor technology. Built upon the sensor development, large research infrastructure facilities, such as National Ecological Observatory Network (NEON) and FLUXNET, have been established. Through networking different kinds of sensors and other data collections at many locations all over the world, those facilities generate large volumes of ecological data every day. The big data from those facilities offer an unprecedented opportunity for advancing our understanding of ecological processes, educating teachers and students, supporting decision-making, and testing ecological theory. The big data from the major research infrastructure facilities also provides foundation for developing predictive ecology. Indeed, the capability to predict future changes in our living environment and natural resources is critical to decision making in a world where the past is no longer a clear guide to the future. We are living in a period marked by rapid climate change, profound alteration of biogeochemical cycles, unsustainable depletion of natural resources, and deterioration of air and water quality. Projecting changes in future ecosystem services to the society becomes essential not only for science but also for policy making. We will use this panel format to outline major opportunities and challenges in integrating research infrastructure and ecosystem models toward developing predictive ecology. Meanwhile, we will also show results from an interactive model-experiment System - Ecological Platform for Assimilating Data into models (EcoPAD) - that have been implemented at the Spruce and Peatland Responses Under Climatic and Environmental change (SPRUCE) experiment in Northern Minnesota and Montpellier Ecotron, France. EcoPAD is developed by integrating web technology, eco-informatics, data assimilation techniques, and ecosystem modeling. EcoPAD is designed to streamline data transfer seamlessly from research infrastructure

A philosophical analysis of David Orr's theory of ecological literacy: biophilia, ecojustice and moral education in school learning communities

NASA Astrophysics Data System (ADS)

Mitchell, Debra B.; Mueller, Michael P.

2011-03-01

In his writings, David Orr claims that the US is in an "ecological crisis" and that this stems from a crisis of education. He outlines a theory of ecological literacy, a mode by which we better learn the ecology of the Earth and live in a sustainable manner. While emphasizing a shock doctrine, the diagnosis of "crisis" may be correct, but it is short-lived for children and adults of the world. In this philosophical analysis of Orr's theory, it is argued that we move beyond the perspective of crisis. By extending Orr's ecological literacy with biophilia and ecojustice and by recognizing the importance of experience-in-learning, science education is envisioned to incorporate values and morals within a longer term ideology of educational reform.

β-Decay half-lives and nuclear structure of exotic proton-rich waiting point nuclei under rp-process conditions

NASA Astrophysics Data System (ADS)

Nabi, Jameel-Un; Böyükata, Mahmut

2016-03-01

We investigate even-even nuclei in the A ∼ 70 mass region within the framework of the proton-neutron quasi-particle random phase approximation (pn-QRPA) and the interacting boson model-1 (IBM-1). Our work includes calculation of the energy spectra and the potential energy surfaces V (β , γ) of Zn, Ge, Se, Kr and Sr nuclei with the same proton and neutron number, N = Z. The parametrization of the IBM-1 Hamiltonian was performed for the calculation of the energy levels in the ground state bands. Geometric shape of the nuclei was predicted by plotting the potential energy surfaces V (β , γ) obtained from the IBM-1 Hamiltonian in the classical limit. The pn-QRPA model was later used to compute half-lives of the neutron-deficient nuclei which were found to be in very good agreement with the measured ones. The pn-QRPA model was also used to calculate the Gamow-Teller strength distributions and was found to be in decent agreement with the measured data. We further calculate the electron capture and positron decay rates for these N = Z waiting point (WP) nuclei in the stellar environment employing the pn-QRPA model. For the rp-process conditions, our total weak rates are within a factor two compared with the Skyrme HF +BCS +QRPA calculation. All calculated electron capture rates are comparable to the competing positron decay rates under rp-process conditions. Our study confirms the finding that electron capture rates form an integral part of the weak rates under rp-process conditions and should not be neglected in the nuclear network calculations.

Effects of the antibiotic enrofloxacin on the ecology of tropical eutrophic freshwater microcosms.

PubMed

Rico, Andreu; Dimitrov, Mauricio R; Van Wijngaarden, René P A; Satapornvanit, Kriengkrai; Smidt, Hauke; Van den Brink, Paul J

2014-02-01

The main objective of the present study was to assess the ecological impacts of the fluoroquinolone antibiotic enrofloxacin on the structure and functioning of tropical freshwater ecosystems. Enrofloxacin was applied at a concentration of 1, 10, 100 and 1,000 μg/L for 7 consecutive days in 600-L outdoor microcosms in Thailand. The ecosystem-level effects of enrofloxacin were monitored on five structural (macroinvertebrates, zooplankton, phytoplankton, periphyton and bacteria) and two functional (organic matter decomposition and nitrogen cycling) endpoint groups for 4 weeks after the last antibiotic application. Enrofloxacin was found to dissipate relatively fast from the water column (half-dissipation time: 11.7h), and about 11% of the applied dose was transformed into its main by-product ciprofloxacin after 24h. Consistent treatment-related effects on the invertebrate and primary producer communities and on organic matter decomposition could not be demonstrated. Enrofloxacin significantly affected the structure of leaf-associated bacterial communities at the highest treatment level, and reduced the abundance of ammonia-oxidizing bacteria and ammonia-oxidizing archaea in the sediments, with calculated NOECs of 10 and <1 μg/L, respectively. The ammonia concentration in the microcosm water significantly increased in the highest treatment level, and nitrate production was decreased, indicating a potential impairment of the nitrification function at concentrations above 100 μg/L. The results of this study suggest that environmentally relevant concentrations of enrofloxacin are not likely to result in direct or indirect toxic effects on the invertebrate and primary producer communities, nor on important microbially mediated functions such as nitrification. Copyright © 2014 Elsevier B.V. All rights reserved.

Transformative Moral Education: Challenging an Ecology of Violence

ERIC Educational Resources Information Center

Joseph, Pamela Bolotin; Mikel, Edward

2014-01-01

From the perspective that we live amidst an ecology of violence, we contend that educators should not circumscribe their ethical roles by endorsing the dominant individualistic goals and practices of moral education. To counter a pervading worldview of violence and tolerance for violence, we propose instead that teachers embrace the multifaceted…

[Cytokine dysregulation in children with chronic catarrhal gingivitis living in polluted areas with fluoride and iodine deficiency].

PubMed

Bezvushko, E V; Malko, N V

The aim of the research was to study the state of oral liquid immunity in children with chronic catarrhal gingivitis living in unfavorable environmental conditions. The study included 190 children with chronic catarrhal gingivitis (CCG): 110 children aged 7, 12 and 15 years and residing in ecologically unfavorable areas of Lviv region and 80 children living in 'conditionally clean' region which constituted comparison group. Children with CCG from polluted areas had increased content of pro-inflammatory cytokines and reduction of anti-inflammatory cytokines compared to controls. The level of pro-inflammatory cytokines was age-depended in both groups but in children from ecologically unfavorable region this tendency was more pronounced. Thus, changes of indicators of interleukin spectrum in children with CCG depend not only on age and degree of severity of periodontium pathology but also on ecological living conditions.

Numerical method of carbon-based material ablation effects on aero-heating for half-sphere

NASA Astrophysics Data System (ADS)

Wang, Jiang-Feng; Li, Jia-Wei; Zhao, Fa-Ming; Fan, Xiao-Feng

2018-05-01

A numerical method of aerodynamic heating with material thermal ablation effects for hypersonic half-sphere is presented. A surface material ablation model is provided to analyze the ablation effects on aero-thermal properties and structural heat conduction for thermal protection system (TPS) of hypersonic vehicles. To demonstrate its capability, applications for thermal analysis of hypersonic vehicles using carbonaceous ceramic ablators are performed and discussed. The numerical results show the high efficiency and validation of the method developed in thermal characteristics analysis of hypersonic aerodynamic heating.

Half-life measurements of isomeric states populated in projectile fragmentation

NASA Astrophysics Data System (ADS)

Bowry, M.; Podolyák, Zs.; Kurcewicz, J.; Pietri, S.; Bunce, M.; Regan, P. H.; Farinon, F.; Geissel, H.; Nociforo, C.; Prochazka, A.; Weick, H.; Allegro, P.; Benlliure, J.; Benzoni, G.; Boutachkov, P.; Gerl, J.; Gorska, M.; Gottardo, A.; Gregor, N.; Janik, R.; Knöbel, R.; Kojouharov, I.; Kubo, T.; Litvinov, Y. A.; Merchan, E.; Mukha, I.; Naqvi, F.; Pfeiffer, B.; Pfützner, M.; Plaß, W.; Pomorski, M.; Riese, B.; Ricciardi, M. V.; Schmidt, K.-H.; Schaffner, H.; Kurz, N.; Denis Bacelar, A. M.; Bruce, A. M.; Farrelly, G. F.; Alkhomashi, N.; Al-Dahan, N.; Scheidenberger, C.; Sitar, B.; Spiller, P.; Stadlmann, J.; Strmen, P.; Sun, B.; Takeda, H.; Tanihata, I.; Terashima, S.; Valiente Dobon, J. J.; Winfield, J. S.; Wollersheim, H.-J.; Woods, P. J.

2012-10-01

The half-lives of excited isomeric states observed in 195Au, 201Tl and 215Rn are reported for the first time. Delayed γ-rays were correlated with nuclei produced in the projectile fragmentation of relativistic 238U ions, unambiguously identified in terms of their atomic number (Z) and mass-to-charge ratio (A/Q) after traversing an in-flight separator. The observation of a long-lived isomeric state in 195Au with t1/2 = 16-4+8 μs is presented. Two shorter-lived isomeric states were detected in 201Tl and 215Rn with t1/2 = 95-21+39 and 57-12+21 ns respectively. In total 24 isomeric states were identified in different nuclei from Pt to Rn (A ˜ 200) during the current study, the majority of which were previously reported. The wealth of spectroscopic data provides the opportunity to determine the isomeric ratios over a wide range of Z, A and angular momentum (I ħ) of the reaction products. In particular, high-spin states with I ≳ 18 ħ provide a robust test of theoretical models of fragmentation.

Designing of peptides with desired half-life in intestine-like environment.

PubMed

Sharma, Arun; Singla, Deepak; Rashid, Mamoon; Raghava, Gajendra Pal Singh

2014-08-20

-life of peptides and to design mutant peptides with better half-life and physicochemical properties. HLP models were trained using a dataset of peptides whose half-lives have been determined experimentally in crude intestinal proteases preparation. Thus, HLP server will help in designing peptides possessing the potential to be administered via oral route (http://www.imtech.res.in/raghava/hlp/).

Ethnic Clusters in Public Housing and Independent Living of Elderly Immigrants from the Former Soviet Union.

PubMed

Vinokurov, Andrey; Trickett, Edison J

2015-12-01

The study examines the effects of ethnic clusters and independent living arrangements on adaptation of elderly immigrants from the Former Soviet Union. The multigenerational living arrangements were compared with independent living in a dispersed ethnic community and in an ethnic cluster of public housing. The residents of the ethnic clusters of public housing reported poorer health, were more reliant on government resources, and experienced greater acculturative hassles. However, public housing residents reported significantly larger Russian-speaking and American social networks, greater American acculturation, higher social support from neighbors, as well as lower cultural alienation. In contrast, the multigenerational living arrangements were related to greater social support from extended family and higher extended family satisfaction. While, the independent living in the dispersed ethnic community was associated with smaller American social networks and higher levels of cultural alienation. The results highlight how the ecologies of different living arrangements are reflected in the nature of acculturative, social, and psychological experiences of elderly immigrants.

The cumulative effects assessment of a coastal ecological restoration project in China: An integrated perspective.

PubMed

Ma, Deqiang; Zhang, Liyu; Fang, Qinhua; Jiang, Yuwu; Elliott, Michael

2017-05-15

Large scale coastal land-claim and sea-enclosing (CLASE) activities have caused habitat destruction, biodiversity losses and water deterioration, thus the local governments in China have recently undertaken seabed dredging and dyke opening (SDADO) as typical ecological restoration projects. However, some projects focus on a single impact on hydrodynamic conditions, water quality or marine organisms. In a case study in Xiamen, China, an integrated effects assessment framework centres on ecohydrology, using modeling of hydrodynamic conditions and statistical analysis of water quality, was developed to assess the effects of ecological restoration projects. The benefits of SDADO projects include improving hydrodynamic conditions and water quality, as a precursor to further marine biological improvements. This study highlights the need to comprehensively consider ecological effects of SDADO projects in the planning stage, and an integrative assessment method combining cumulative effects of hydrodynamic conditions, water quality and biological factors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Chlamydial infections in free-living birds

USGS Publications Warehouse

Brand, C.J.

1989-01-01

Most studies of chlamydial infections in free-living wild birds have been limited to surveys for the presence of Chlamydia psittaci or antibody to C psittaci and have largely been done in association with the identification of chlamydiosis in human beings, commercial fowl, or pet birds. The emphasis of these studies has been to determine the prevalence of infection and the potential role of wild birds in the spread of chlamydiae to domestic birds and human beings. Little is known about the epizootiology of chlamydiosis in free-living birds or its affect on their population dynamics. The following article is a summary of reported studies of chlamydiosis in free-living wild birds in relation to host range, ecologic aspects of transmission and maintenance, and the prevalence of disease.

Ecological and socioeconomic effects of China's policies for ecosystem services.

PubMed

Liu, Jianguo; Li, Shuxin; Ouyang, Zhiyun; Tam, Christine; Chen, Xiaodong

2008-07-15

To address devastating environmental crises and to improve human well-being, China has been implementing a number of national policies on payments for ecosystem services. Two of them, the Natural Forest Conservation Program (NFCP) and the Grain to Green Program (GTGP), are among the biggest programs in the world because of their ambitious goals, massive scales, huge payments, and potentially enormous impacts. The NFCP conserves natural forests through logging bans and afforestation with incentives to forest enterprises, whereas the GTGP converts cropland on steep slopes to forest and grassland by providing farmers with grain and cash subsidies. Overall ecological effects are beneficial, and socioeconomic effects are mostly positive. Whereas there are time lags in ecological effects, socioeconomic effects are more immediate. Both the NFCP and the GTGP also have global implications because they increase vegetative cover, enhance carbon sequestration, and reduce dust to other countries by controlling soil erosion. The future impacts of these programs may be even bigger. Extended payments for the GTGP have recently been approved by the central government for up to 8 years. The NFCP is likely to follow suit and receive renewed payments. To make these programs more effective, we recommend systematic planning, diversified funding, effective compensation, integrated research, and comprehensive monitoring. Effective implementation of these programs can also provide important experiences and lessons for other ecosystem service payment programs in China and many other parts of the world.

Effect of ecological immune-enhanced enteral nutrition on patients with gastrointestinal fistulas.

PubMed

Wang, Q-H

2017-05-01

The aim of this study was to determine the effects of early ecological immune-enhanced enteral nutrition on the nutritional status, immune function and intestinal mucosal barrier in patients with gastrointestinal fistulas. 54 patients with gastrointestinal fistulas were randomized to either the ecological immune-enhanced enteral nutrition group (EIEN group, 28) or the parenteral nutrition group (PN group, 26). The changes in the immunity, nutrition index and intestinal mucosal barrier indexes before the ecological immune-enhanced enteral nutrition support and at 7 days and 14 days after the ecological immune-enhanced enteral nutrition support were determined. Compared with the PN group, the indexes of the CD3 and CD4 positive cells, the CD4/CD8 values and the plasma levels of IgA and IgM were significantly higher than those in EIEN group (p<0.05). Moreover, with EIEN nutritional support, the nutrition indexes, such as the plasma ALB, PA and TFN, and the intestinal mucosal barrier index (the plasma D-lactate levels and endotoxin levels), also recovered gradually to normal levels and were higher than those of the PN group (p<0.05). For patients with gastrointestinal fistulas, ecological immune-enhanced enteral nutrition can not only improve the cellular immunity function, humoral immunity, and nutritional status but also enhance the intestinal mucosal barrier.

Energy, food, and land-- the ecological traps of humankind.

PubMed

Haber, Wolfgang

2007-09-01

Humans' superiority over all other organisms on earth rests on five main foundations: command of fire requiring fuel; controlled production of food and other biotic substances; utilization of metals and other non-living materials for construction and appliances; technically determined, urban-oriented living standard; economically and culturally regulated societal organization. The young discipline of ecology has revealed that the progress of civilization and technology attained, and being further pursued by humankind, and generally taken for granted and permanent, is leading into ecological traps. This metaphor circumscribes ecological situations where finite resources are being exhausted or rendered non-utilizable without a realistic prospect of restitution. Energy, food and land are the principal, closely interrelated traps; but the absolutely decisive resource in question is land whose increasing scarcity is totally underrated. Land is needed for fulfilling growing food demands, for producing renewable energy in the post-fossil and post-nuclear era, for maintaining other ecosystem services, for urban-industrial uses, transport, material extraction, refuse deposition, but also for leisure, recreation, and nature conservation. All these needs compete for land, food and non-food biomass production moreover for good soils that are scarcer than ever. We are preoccupied with fighting climate change and loss of biodiversity; but these are minor problems we could adapt to, albeit painfully, and their solution will fail if we are caught in the interrelated traps of energy, food, and land scarcity. Land and soils, finite and irreproducible resources, are the key issues we have to devote our work to, based on careful ecological information, planning and design for proper uses and purposes. The article concludes with a short reflection on economy and competition as general driving forces, and on the role and reputation of today's ecology.

EPA/OFFICE OF RESEARCH AND DEVELOPMENT'S NATIONAL HEALTH AND ENVIRONMENTAL EFFECTS RESEARCH LABORATORY/WESTERN ECOLOGY DIVISION INTERNET SITE

EPA Science Inventory

The Western Ecology Division (WED) is one of four ecological effects divisions of the National Health and Environmental Effects Research Laboratory. The four divisions are distributed bio-geographically. WED's mission is 1) to provide EPA with national scientific leadership for t...

A shifting paradigm: Teachers' beliefs and methods for fostering ecological literacy in two public charter schools

NASA Astrophysics Data System (ADS)

Sterling, Evan P.

Ecological literacy is measured by a person's ability to understand the natural systems that make life on earth possible and how to live in accordance with those systems. The emergence of the pedagogies of place- and community-based education during the past two decades provides a possible avenue for fostering ecological literacy in schools. This thesis explores the following research questions: 1) How is ecological literacy fostered in two Alaskan public charter schools? 2) What are teachers' beliefs in these two schools about the way children and youth develop ecological literacy? 3) What are effective teaching methods and what are the challenges in engaging students in ecological literacy? Semi-structured interviews were conducted with six K--12 teachers in two public charter schools in Alaska in order to investigate these questions, and relevant examples of student work were collected for study as well. Qualitative data analysis revealed several emergent themes: the need for real-world connections to curriculum; the necessity of time spent outdoors at a young age; the long-term and holistic nature of ecological literacy development; and the importance of family and community role models in developing connections with the natural world. Based upon the research findings, several recommendations are made to support the efforts of teachers in these schools and elsewhere for fostering ecological literacy in children and youth.

An Investigation of the Effectiveness of Computer Simulation Programs as Tutorial Tools for Teaching Population Ecology at University.

ERIC Educational Resources Information Center

Korfiatis, K.; Papatheodorou, E.; Paraskevopoulous, S.; Stamou, G. P.

1999-01-01

Describes a study of the effectiveness of computer-simulation programs in enhancing biology students' familiarity with ecological modeling and concepts. Finds that computer simulations improved student comprehension of ecological processes expressed in mathematical form, but did not allow a full understanding of ecological concepts. Contains 28…

Half-marathoners are younger and slower than marathoners.

PubMed

Knechtle, Beat; Nikolaidis, Pantelis T; Zingg, Matthias A; Rosemann, Thomas; Rüst, Christoph A

2016-01-01

Age and performance trends of elite and recreational marathoners are well investigated, but not for half-marathoners. We analysed age and performance trends in 508,108 age group runners (125,894 female and 328,430 male half-marathoners and 10,205 female and 43,489 male marathoners) competing between 1999 and 2014 in all flat half-marathons and marathons held in Switzerland using single linear regression analyses, mixed-effects regression analyses and analyses of variance. The number of women and men increased across years in both half-marathons and marathons. There were 12.3 times more female half-marathoners than female marathoners and 7.5 times more male half-marathoners than male marathoners. For both half-marathons and marathons, most of the female and male finishers were recorded in age group 40-44 years. In half-marathons, women (10.29 ± 3.03 km/h) were running 0.07 ± 0.06 km/h faster (p < 0.001) than men (10.22 ± 3.06 km/h). Also in marathon, women (14.77 ± 4.13 km/h) were running 0.28 ± 0.16 km/h faster (p < 0.001) than men (14.48 ± 4.07 km/h). In marathon, women (42.18 ± 10.63 years) were at the same age than men (42.06 ± 10.45 years) (p > 0.05). Also in half-marathon, women (41.40 ± 10.63 years) were at the same age than men (41.31 ± 10.30 years) (p > 0.05). However, women and men marathon runners were older than their counterpart half-marathon runners (p < 0.001). In summary, (1) more athletes competed in half-marathons than in marathons, (2) women were running faster than men, (3) half-marathoners were running slower than marathoners, and (4) half-marathoners were younger than marathoners.

Predictive ecology: systems approaches

PubMed Central

Evans, Matthew R.; Norris, Ken J.; Benton, Tim G.

2012-01-01

The world is experiencing significant, largely anthropogenically induced, environmental change. This will impact on the biological world and we need to be able to forecast its effects. In order to produce such forecasts, ecology needs to become more predictive—to develop the ability to understand how ecological systems will behave in future, changed, conditions. Further development of process-based models is required to allow such predictions to be made. Critical to the development of such models will be achieving a balance between the brute-force approach that naively attempts to include everything, and over simplification that throws out important heterogeneities at various levels. Central to this will be the recognition that individuals are the elementary particles of all ecological systems. As such it will be necessary to understand the effect of evolution on ecological systems, particularly when exposed to environmental change. However, insights from evolutionary biology will help the development of models even when data may be sparse. Process-based models are more common, and are used for forecasting, in other disciplines, e.g. climatology and molecular systems biology. Tools and techniques developed in these endeavours can be appropriated into ecological modelling, but it will also be necessary to develop the science of ecoinformatics along with approaches specific to ecological problems. The impetus for this effort should come from the demand coming from society to understand the effects of environmental change on the world and what might be performed to mitigate or adapt to them. PMID:22144379

Comparing spatially explicit ecological and social values for natural areas to identify effective conservation strategies.

PubMed

Bryan, Brett Anthony; Raymond, Christopher Mark; Crossman, Neville David; King, Darran

2011-02-01

Consideration of the social values people assign to relatively undisturbed native ecosystems is critical for the success of science-based conservation plans. We used an interview process to identify and map social values assigned to 31 ecosystem services provided by natural areas in an agricultural landscape in southern Australia. We then modeled the spatial distribution of 12 components of ecological value commonly used in setting spatial conservation priorities. We used the analytical hierarchy process to weight these components and used multiattribute utility theory to combine them into a single spatial layer of ecological value. Social values assigned to natural areas were negatively correlated with ecological values overall, but were positively correlated with some components of ecological value. In terms of the spatial distribution of values, people valued protected areas, whereas those natural areas underrepresented in the reserve system were of higher ecological value. The habitats of threatened animal species were assigned both high ecological value and high social value. Only small areas were assigned both high ecological value and high social value in the study area, whereas large areas of high ecological value were of low social value, and vice versa. We used the assigned ecological and social values to identify different conservation strategies (e.g., information sharing, community engagement, incentive payments) that may be effective for specific areas. We suggest that consideration of both ecological and social values in selection of conservation strategies can enhance the success of science-based conservation planning. ©2010 Society for Conservation Biology.

Looking East at BottomHalf of Reactor Number One and TopHalf ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Looking East at Bottom-Half of Reactor Number One and Top-Half of Reactor Number 2 Including Weigh Hopper on Third Floor of Oxide Building - Hematite Fuel Fabrication Facility, Oxide Building & Oxide Loading Dock, 3300 State Road P, Festus, Jefferson County, MO

Ecological Limits to Terrestrial Carbon Dioxide Removal Strategies

NASA Astrophysics Data System (ADS)

Smith, L. J.; Torn, M. S.; Jones, A. D.

2011-12-01

Carbon dioxide removal from the atmosphere through terrestrial carbon sequestration and bioenergy (biological CDR) is a proposed climate change mitigation strategy. Biological CDR increases the carbon storage capacity of soils and biomass through changes in land cover and use, including reforestation, afforestation, conversion of land to agriculture for biofuels, conversion of degraded land to grassland, and alternative management practices such as conservation tillage. While biological CDR may play a valuable role in future climate change mitigation, many of its proponents fail to account for the full range of biological, biophysical, hydrologic, and economic complexities associated with proposed land use changes. In this analysis, we identify and discuss a set of ecological limits and impacts associated with terrestrial CDR. The capacity of biofuels, soils, and other living biomass to sequester carbon may be constrained by nutrient and water availability, soil dynamics, and local climate effects, all of which can change spatially and temporally in unpredictable ways. Even if CDR is effective at sequestering CO2, its associated land use and land cover changes may negatively impact ecological resources by compromising water quality and availability, degrading soils, reducing biodiversity, displacing agriculture, and altering local climate through albedo and evapotranspiration changes. Measures taken to overcome ecological limitations, such as fertilizer addition and irrigation, may exacerbate these impacts even further. The ecological considerations and quantitative analyses that we present highlight uncertainties introduced by ecological complexity, disagreements between models, perverse economic incentives, and changing environmental factors. We do not reject CDR as a potentially valuable strategy for climate change mitigation; ecosystem protection, restoration, and improved management practices could enhance soil fertility and protect biodiversity while reducing

Use of QSARs in international decision-making frameworks to predict ecologic effects and environmental fate of chemical substances.

PubMed Central

Cronin, Mark T D; Walker, John D; Jaworska, Joanna S; Comber, Michael H I; Watts, Christopher D; Worth, Andrew P

2003-01-01

This article is a review of the use, by regulatory agencies and authorities, of quantitative structure-activity relationships (QSARs) to predict ecologic effects and environmental fate of chemicals. For many years, the U.S. Environmental Protection Agency has been the most prominent regulatory agency using QSARs to predict the ecologic effects and environmental fate of chemicals. However, as increasing numbers of standard QSAR methods are developed and validated to predict ecologic effects and environmental fate of chemicals, it is anticipated that more regulatory agencies and authorities will find them to be acceptable alternatives to chemical testing. PMID:12896861

[Interception Effect of Ecological Ditch on Nitrogen Transport in Agricultural Runoff in Subtropical China].

PubMed

Wang, Di; Li, Hong-fang; Liu, Feng; Wang, Yi; Zhong, Yuan-chun; He, Yang; Xiao, Run-fin; Wu, Jin-shui

2016-05-15

Interception effects of an ecological ditch, used to control agricultural non-point source pollution in subtropical China, on nitrogen transport in surface runoff were studied by monthly measuring the runoff volume and concentrations of ammonium nitrogen (NH₄⁺-N), nitrate nitrogen (NO₃⁻-N) and total nitrogen (TN) at the ditch inlet and outlet from 2013 to 2014. In addition, differences of NH₄⁺-N, NO₃⁻-N and TN removal were compared between 2013 and 2014. The results showed that the study ecological ditch worked effectively in N removal with average NH₄⁺-N, NO₃⁻-N and TN removal rates of 77.8%, 58.3%, and 48.7%; and their interception rates were 38.4, 59.6, and 171.1 kg · a⁻¹, respectively. The average proportion of NH₄⁺-N and NO₃⁻-N in TN was 47.5% at inlet, and 33.6% at outlet, which was significantly lower than that at inlet (P < 0.01). All hydrophytes in the ecological ditch were replaced by Myriophyllum aquaticum in 2014, which led to the increased average NO₃⁻-N and TN removal rates of 30.5% and 18.2%, respectively, Compared to in 2013. The vegetation of Myriophyllum aquaticum was beneficial to the improvement of N interception in ecological ditch. These findings clearly demonstrated that ecological ditch can substantially reduce N loss from surface runoff and be used as an important technique to prevent agricultural non-point N pollution.

On the half-life of luminescence signals in dosimetric applications: A unified presentation

NASA Astrophysics Data System (ADS)

Pagonis, V.; Kitis, G.; Polymeris, G. S.

2018-06-01

Luminescence signals from natural and man-made materials are widely used in dosimetric and dating applications. In general, there are two types of half-lives of luminescence signals which are of importance to experimental and modeling work in this research area. The first type of half-life is the time required for the population of the trapped charge in a single trap to decay to half its initial value. The second type of half-life is the time required for the luminescence intensity to drop to half of its initial value. While there a handful of analytical expressions available in the literature for the first type of half-life, there are no corresponding analytical expressions for the second type. In this work new analytical expressions are derived for the half-life of luminescence signals during continuous wave optical stimulation luminescence (CW-OSL) or isothermal luminescence (ITL) experiments. The analytical expressions are derived for several commonly used luminescence models which are based on delocalized transitions involving the conduction band: first and second order kinetics, empirical general order kinetics (GOK), mixed order kinetics (MOK) and the one-trap one-recombination center (OTOR) model. In addition, half-life expressions are derived for a different type of luminescence model, which is based on localized transitions in a random distribution of charges. The new half-life expressions contain two parts. The first part is inversely proportional to the thermal or optical excitation rate, and depends on the experimental conditions and on the cross section of the relevant luminescence process. The second part is characteristic of the optical and/or thermal properties of the material, as expressed by the parameters in the model. A new simple and quick method for analyzing luminescence signals is developed, and examples are given of applying the new method to a variety of dosimetric materials. The new test allows quick determination of whether a set of

Search for effective spin injection heterostructures based on half-metal Heusler alloys/gallium arsenide semiconductors: A theoretical investigation

NASA Astrophysics Data System (ADS)

Sivakumar, Chockalingam

Efficient electrical spin injection from half-metal (HM) electrodes into semiconducting (SC) channel material is a desirable aspect in spintronics, but a challenging one. Half-metals based on the Heusler alloy family are promising candidates as spin sources due to their compatibility with compound SCs, and very high Curie temperatures. Numerous efforts were made in the past two decades to grow atomically abrupt interfaces between HM_Heusler and SC heterostructures. However, diffusion of magnetic impurities into the semiconductor, defects and disorder near the interface, and formation of reacted phases were great challenges. A number of theoretical efforts were undertaken to understand the role of such material defects in destroying the half-metallicity and also to propose promising half-metal/SC heterostructures based on first principles. This dissertation summarizes the investigations undertaken to decode the complexity of, and to understand the various physical properties of, a number of real-world Heusler/SC heterostructure samples, based on the ab initio density functional theory (DFT) approach. In addition, it summarizes various results from the first principles-based search for promising half-metal/SC heterostructures. First, I present results from DFT-based predictive models of actual Co 2MnSi (CMS)/GaAs heterostructures grown in (001) texture. I investigate the physical, chemical, electronic, and magnetic properties to understand the complexity of these structures and to pinpoint the origin of interfacial effects, when present. Based on the investigations of such models, I discuss the utility of those actual samples in spintronic applications. Next, I summarise the results from an ab initio DFT-based survey of 6 half-Heusler half-metal/GaAs heterostructure models in (110) texture, since compound semiconductors such as GaAs have very long spin lifetime in (110) layering. I show 3 half-Heusler alloys (CoVAs, NiMnAs, and RhFeGe), that when interfaced with Ga

Measurement of the 20F half-life

NASA Astrophysics Data System (ADS)

Hughes, M.; George, E. A.; Naviliat-Cuncic, O.; Voytas, P. A.; Chandavar, S.; Gade, A.; Huyan, X.; Liddick, S. N.; Minamisono, K.; Paulauskas, S. V.; Weisshaar, D.

2018-05-01

The half-life of the 20F ground state was measured using a radioactive beam implanted in a plastic scintillator and recording β γ coincidences together with four CsI(Na) detectors. The result, T1 /2=11.0011 (69) stat(30) sys s, is at variance by 17 combined standard deviations with the two most precise results. The present value revives the poor consistency of results for this half-life and calls for a new measurement, with a technique having different sources of systematic effects, to clarify the discrepancy.

A Philosophical Analysis of David Orr's Theory of Ecological Literacy: Biophilia, Ecojustice and Moral Education in School Learning Communities

ERIC Educational Resources Information Center

Mitchell, Debra B.; Mueller, Michael P.

2011-01-01

In his writings, David Orr claims that the US is in an "ecological crisis" and that this stems from a crisis of education. He outlines a theory of ecological literacy, a mode by which we better learn the ecology of the Earth and live in a sustainable manner. While emphasizing a shock doctrine, the diagnosis of "crisis" may be…

Ecological validity of cost-effectiveness models of universal HPV vaccination: A systematic literature review.

PubMed

Favato, Giampiero; Easton, Tania; Vecchiato, Riccardo; Noikokyris, Emmanouil

2017-05-09

The protective (herd) effect of the selective vaccination of pubertal girls against human papillomavirus (HPV) implies a high probability that one of the two partners involved in intercourse is immunised, hence preventing the other from this sexually transmitted infection. The dynamic transmission models used to inform immunisation policy should include consideration of sexual behaviours and population mixing in order to demonstrate an ecological validity, whereby the scenarios modelled remain faithful to the real-life social and cultural context. The primary aim of this review is to test the ecological validity of the universal HPV vaccination cost-effectiveness modelling available in the published literature. The research protocol related to this systematic review has been registered in the International Prospective Register of Systematic Reviews (PROSPERO: CRD42016034145). Eight published economic evaluations were reviewed. None of the studies showed due consideration of the complexities of human sexual behaviour and the impact this may have on the transmission of HPV. Our findings indicate that all the included models might be affected by a different degree of ecological bias, which implies an inability to reflect the natural demographic and behavioural trends in their outcomes and, consequently, to accurately inform public healthcare policy. In particular, ecological bias have the effect to over-estimate the preference-based outcomes of selective immunisation. A relatively small (15-20%) over-estimation of quality-adjusted life years (QALYs) gained with selective immunisation programmes could induce a significant error in the estimate of cost-effectiveness of universal immunisation, by inflating its incremental cost effectiveness ratio (ICER) beyond the acceptability threshold. The results modelled here demonstrate the limitations of the cost-effectiveness studies for HPV vaccination, and highlight the concern that public healthcare policy might have been

Generalized herd effects and vaccine evaluation: impact of live influenza vaccine on off-target bacterial colonisation.

PubMed

Mina, Michael J

2017-06-01

Interactions between pathogens and commensal microbes are major contributors to health and disease. Infectious diseases however are most often considered independent, viewed within a one-host one-pathogen paradigm and, by extension, the interventions used to treat and prevent them are measured and evaluated within this same paradigm. Vaccines, especially live vaccines, by stimulating immune responses or directly interacting with other microbes can alter the environment in which they act, with effects that span across pathogen species. Live attenuated infl uenza vaccines for example, while safe, increase upper respiratory tract bacterial carriage density of important human commensal pathogens like Streptococcus pneumoniae and Staphylococcus aureus. Further, by altering the ecological niche and dynamics of phylogenetically distinct microbes within the host, vaccines may unintentionally affect transmission of non-vaccine targeted pathogens. Thus, vaccine effects may span across species and across scales, from the individual to the population level. In keeping with traditional vaccine herd-effects that indirectly protect even unvaccinated individuals by reducing population prevalence of vaccine-targeted pathogens, we call these cross-species cross-scale effects "generalized herd-effects". As opposed to traditional herd-effects, "generalized" relaxes the assumption that the effect occurs at the level of the vaccine-target pathogen and "herd effect" implies, as usual, that the effects indirectly impact the population at large, including unvaccinated bystanders. Unlike traditional herd-effects that decrease population prevalence of the vaccine-target, generalized herd-effects may decrease or increase prevalence and disease by the off-target pathogen. LAIV, for example, by increasing pneumococcal density in the upper respiratory tract of vaccine recipients, especially children, may increase pneumococcal transmission and prevalence, leading to excess pneumococcal invasive

Landscape fragmentation and pollinator movement within agricultural environments: a modelling framework for exploring foraging and movement ecology

PubMed Central

2014-01-01

Pollinator decline has been linked to landscape change, through both habitat fragmentation and the loss of habitat suitable for the pollinators to live within. One method for exploring why landscape change should affect pollinator populations is to combine individual-level behavioural ecological techniques with larger-scale landscape ecology. A modelling framework is described that uses spatially-explicit individual-based models to explore the effects of individual behavioural rules within a landscape. The technique described gives a simple method for exploring the effects of the removal of wild corridors, and the creation of wild set-aside fields: interventions that are common to many national agricultural policies. The effects of these manipulations on central-place nesting pollinators are varied, and depend upon the behavioural rules that the pollinators are using to move through the environment. The value of this modelling framework is discussed, and future directions for exploration are identified. PMID:24795848

Landscape fragmentation and pollinator movement within agricultural environments: a modelling framework for exploring foraging and movement ecology.

PubMed

Rands, Sean A

2014-01-01

Pollinator decline has been linked to landscape change, through both habitat fragmentation and the loss of habitat suitable for the pollinators to live within. One method for exploring why landscape change should affect pollinator populations is to combine individual-level behavioural ecological techniques with larger-scale landscape ecology. A modelling framework is described that uses spatially-explicit individual-based models to explore the effects of individual behavioural rules within a landscape. The technique described gives a simple method for exploring the effects of the removal of wild corridors, and the creation of wild set-aside fields: interventions that are common to many national agricultural policies. The effects of these manipulations on central-place nesting pollinators are varied, and depend upon the behavioural rules that the pollinators are using to move through the environment. The value of this modelling framework is discussed, and future directions for exploration are identified.

[Engineering issues of microbial ecology in space agriculture].

PubMed

Yamashita, Masamichi; Ishikawa, Yoji; Oshima, Tairo

2005-03-01

Closure of the materials recycle loop for water-foods-oxygen is the primary purpose of space agriculture on Mars and Moon. A microbial ecological system takes a part of agriculture to process our metabolic excreta and inedible biomass and convert them to nutrients and soil substrate for cultivating plants. If we extend the purpose of space agriculture to the creation and control of a healthy and pleasant living environment, we should realize that our human body should not be sterilized but exposed to the appropriate microbial environment. We are proposing a use of hyper-thermophilic aerobic composting microbial ecology in space agriculture. Japan has a broad historical and cultural background on this subject. There had been agriculture that drove a closed loop of materials between consuming cities and farming villages in vicinity. Recent environmental problems regarding garbage collection and processing in towns have motivated home electronics companies to innovate "garbage composting" machines with bacterial technology. Based on those matured technology, together with new insights on microbiology and microbial ecology, we have been developing a conceptual design of space agriculture on Moon and Mars. There are several issues to be answered in order to prove effectiveness of the use of microbial systems in space. 1) Can the recycled nutrients, processed by the hyper-thermal aerobic composting microbial ecology, be formed in the physical and chemical state or configuration, with which plants can uptake those nutrients? A possibility of removing any major components of fertilizer from its recycle loop is another item to be evaluated. 2) What are the merits of forming soil microbial ecology around the root system of plants? This might be the most crucial question. Recent researches exhibit various mutually beneficial relationships among soil microbiota and plants, and symbiotic ecology in composting bacteria. It is essential to understand those features, and define

Enlightening Butterfly Conservation Efforts: The Importance of Natural Lighting for Butterfly Behavioral Ecology and Conservation

PubMed Central

2018-01-01

Light is arguably the most important abiotic factor for living organisms. Organisms evolved under specific lighting conditions and their behavior, physiology, and ecology are inexorably linked to light. Understanding light effects on biology could not be more important as present anthropogenic effects are greatly changing the light environments in which animals exist. The two biggest anthropogenic contributors changing light environments are: (1) anthropogenic lighting at night (i.e., light pollution); and (2) deforestation and the built environment. I highlight light importance for butterfly behavior, physiology, and ecology and stress the importance of including light as a conservation factor for conserving butterfly biodiversity. This review focuses on four parts: (1) Introducing the nature and extent of light. (2) Visual and non-visual light reception in butterflies. (3) Implications of unnatural lighting for butterflies across several different behavioral and ecological contexts. (4). Future directions for quantifying the threat of unnatural lighting on butterflies and simple approaches to mitigate unnatural light impacts on butterflies. I urge future research to include light as a factor and end with the hopeful thought that controlling many unnatural light conditions is simply done by flipping a switch. PMID:29439549

Donor selection for adult-to-adult living donor liver transplantation: well begun is half done.

PubMed

Sharma, Amit; Ashworth, April; Behnke, Martha; Cotterell, Adrian; Posner, Marc; Fisher, Robert A

2013-02-15

Donor selection criteria for adult-to-adult living donor liver transplantation vary with the medical center of evaluation. Living donor evaluation uses considerable resources, and the nonmaturation of potential into actual donors may sometimes prove fatal for patients with end-stage liver disease. On the contrary, a thorough donor evaluation process is mandatory to ensure safe outcomes in otherwise healthy donors. We aimed to study the reasons for nonmaturation of potential right lobe liver donors at our transplant center. A retrospective data analysis of all potential living liver donors evaluated at our center from 1998 to 2010 was done. Overall, 324 donors were evaluated for 219 potential recipients, and 171 (52.7%) donors were disqualified. Common reasons for donor nonmaturation included the following: (1) donor reluctance, 21%; (2) greater than 10% macro-vesicular steatosis, 16%; (3) assisted donor withdrawal, 14%; (4) inadequate remnant liver volume, 13%; and (5) psychosocial issues, 7%, and thrombophilia, 7%. Ten donors (6%) were turned down because of anatomic variations (8 biliary and 2 arterial anomalies). Donors older than 50 years and those with body mass index of more than 25 were less likely to be accepted for donation. We conclude that donor reluctance, hepatic steatosis, and assisted donor withdrawal are major reasons for nonmaturation of potential into actual donors. Anatomic variations and underlying medical conditions were not a major cause of donor rejection. A system in practice to recognize these factors early in the course of donor evaluation to improve the efficiency of the selection process and ensure donor safety is proposed.

Donor Selection for Adult- to- Adult Living Donor Liver Transplantation: Well Begun is Half Done

PubMed Central

Sharma, Amit; Ashworth, April; Behnke, Martha; Cotterell, Adrian; Posner, Marc; Fisher, Robert A.

2012-01-01

Background Donor selection criteria for adult-to-adult living donor liver transplantation vary with the medical center of evaluation. Living donor evaluation utilizes considerable resources and the non-maturation of potential into actual donors may sometimes prove fatal for patients with end stage liver disease. On the contrary, a thorough donor evaluation process is mandatory to ensure safe outcomes in otherwise healthy donors. We aimed to study the reasons for non-maturation of potential right lobe liver donors at our transplant center. Methods A retrospective data analysis of all potential living liver donors evaluated at our center from 1998 to 2010 was done. Results Overall 324 donors were evaluated for 219 potential recipients and 171 (52.7%) donors were disqualified. Common reasons for donor non-maturation included: (1) Donor reluctance, 21% (2) >10% macro-vesicular steatosis, 16% (3) assisted donor withdrawal, 14% (4) inadequate remnant liver volume, 13% (5) psychosocial issues, 7% and thrombophilia, 7%. Ten donors (6%) were turned down due to anatomical variations (8 biliary and 2 arterial anomalies). Donors older than 50 years and those with BMI over 25 were less likely to be accepted for donation. Conclusions We conclude that donor reluctance, hepatic steatosis and assisted donor withdrawal are major reasons for non-maturation of potential into actual donors. Anatomical variations and underlying medical conditions were not a major cause of donor rejection. A system in practice to recognize these factors early in the course of donor evaluation to improve the efficiency of the selection process and ensure donor safety is proposed. PMID:23128999

Genetic Engineering and Human Mental Ecology: Interlocking Effects and Educational Considerations.

PubMed

Affifi, Ramsey

2017-01-01

This paper describes some likely semiotic consequences of genetic engineering on what Gregory Bateson has called "the mental ecology" (1979) of future humans, consequences that are less often raised in discussions surrounding the safety of GMOs (genetically modified organisms). The effects are as follows: an increased 1) habituation to the presence of GMOs in the environment, 2) normalization of empirically false assumptions grounding genetic reductionism, 3) acceptance that humans are capable and entitled to decide what constitutes an evolutionary improvement for a species, 4) perception that the main source of creativity and problem solving in the biosphere is anthropogenic. Though there are some tensions between them, these effects tend to produce self-validating webs of ideas, actions, and environments, which may reinforce destructive habits of thought. Humans are unlikely to safely develop genetic technologies without confronting these escalating processes directly. Intervening in this mental ecology presents distinct challenges for educators, as will be discussed.

Migration-related detention centers: the challenges of an ecological perspective with a focus on justice.

PubMed

Esposito, Francesca; Ornelas, José; Arcidiacono, Caterina

2015-06-06

In recent years, border control and migration-related detention have become increasingly widespread practices affecting the lives of undocumented migrants, their families, and communities at large. In spite of the concern within academia, few studies have directly witnessed the life and experiences of people confined to migration-related detention centers. In the medical and psychological fields, a considerable body of research has demonstrated the pathogenic nature of detention in terms of mental health, showing an association between length of detention and severity of distress. Nevertheless, it was limited to the assessment of individuals' clinical consequences, mainly focusing on asylum seekers. There currently exists a need to adopt an ecological perspective from which to study detained migrants' experiences as context-dependent, and influenced by power inequalities. This paper addresses this gap. Drawing upon advances in community psychology, we illustrate an ecological framework for the study of migration-related detention contexts, and their effects on the lives of detained migrants and all people exposed to them. Making use of existing literature, Kelly's four principles (interdependence, cycling of resources, adaptation, succession) are analyzed at multiple ecological levels (personal, interpersonal, organizational, communal), highlighting implications for future research in this field. A focus on justice, as a key-dimension of analysis, is also discussed. Wellbeing is acknowledged as a multilevel, dynamic, and value-dependent phenomenon. In presenting this alternative framework, the potential for studying migration-related detention through an ecological lens is highlighted, pointing the way for future fields of study. We argue that ecological multilevel analyses, conceptualized in terms of interdependent systems and with a focus on justice, can enhance the comprehension of the dynamics at play in migration-related detention centers, providing an

Hydrology and Conservation Ecology

NASA Astrophysics Data System (ADS)

Narayanan, M.

2006-12-01

Responses to change in the behavior of ecological systems are largely governed by interactions at different levels. Research is essential and is to be necessarily designed to gain insights into various interactions at the community level. Sustainable resource management is only possible if conservation of biodiversity can be accomplished by properly using the knowledge discovered. It is well known that the United States Department of Agriculture provides technical information, resources, and data necessary to assist the researchers in addressing their conservation needs. Conservation aims to protect, preserve and conserve the earth's natural resources. These include, but not limited to the conservation of soil, water, minerals, air, plants and all living beings. The United States Department of Agriculture also encourages farmers and ranchers to voluntarily address threats to soil and water. Protection of wetlands and wildlife habitat has been on the radar screen of conservation experts for a very long time. The main objective has always been to help farmers and landowners conform and comply with federal and state environmental laws. During the implementation phase, farmers should be encouraged to make beneficial, cost-effective changes to methods of irrigation systems. In some cases, the hydrologic regime of the project area can be thought of as principally an issue of river flow regimes for floodplain forests. In this presentation, the author tries to focus on the impact of hydrology and conservation ecology on global warming. He also discusses the impact of hydrology and conservation ecology global air concerns such as greenhouse gas concentrations in the atmosphere. References: Chow, V. T, D. R. Maidment, and L. W. Mays. 1988. Applied Hydrology. McGraw-Hill, Inc. U.S. Soil Conservation Service. Technical Release 55: Urban Hydrology for Small Watersheds. USDA (U.S. Department of Agriculture). June 1986. Lehner, B. and P. Döll (2004). Development and validation

A guide to statistical analysis in microbial ecology: a community-focused, living review of multivariate data analyses.

PubMed

Buttigieg, Pier Luigi; Ramette, Alban

2014-12-01

The application of multivariate statistical analyses has become a consistent feature in microbial ecology. However, many microbial ecologists are still in the process of developing a deep understanding of these methods and appreciating their limitations. As a consequence, staying abreast of progress and debate in this arena poses an additional challenge to many microbial ecologists. To address these issues, we present the GUide to STatistical Analysis in Microbial Ecology (GUSTA ME): a dynamic, web-based resource providing accessible descriptions of numerous multivariate techniques relevant to microbial ecologists. A combination of interactive elements allows users to discover and navigate between methods relevant to their needs and examine how they have been used by others in the field. We have designed GUSTA ME to become a community-led and -curated service, which we hope will provide a common reference and forum to discuss and disseminate analytical techniques relevant to the microbial ecology community. © 2014 The Authors. FEMS Microbiology Ecology published by John Wiley & Sons Ltd on behalf of Federation of European Microbiological Societies.

Meta-analysis in applied ecology.

PubMed

Stewart, Gavin

2010-02-23

This overview examines research synthesis in applied ecology and conservation. Vote counting and pooling unweighted averages are widespread despite the superiority of syntheses based on weighted combination of effects. Such analyses allow exploration of methodological uncertainty in addition to consistency of effects across species, space and time, but exploring heterogeneity remains controversial. Meta-analyses are required to generalize in ecology, and to inform evidence-based decision-making, but the more sophisticated statistical techniques and registers of research used in other disciplines must be employed in ecology to fully realize their benefits.

Effects of season on ecological processes in extensive earthen tilapia ponds in Southeastern Brazil.

PubMed

Favaro, E G P; Sipaúba-Tavares, L H; Milstein, A

2015-11-01

In Southeastern Brazil tilapia culture is conducted in extensive and semi-intensive flow-through earthen ponds, being water availability and flow management different in the rainy and dry seasons. In this region lettuce wastes are a potential cheap input for tilapia culture. This study examined the ecological processes developing during the rainy and dry seasons in three extensive flow-through earthen tilapia ponds fertilized with lettuce wastes. Water quality, plankton and sediment parameters were sampled monthly during a year. Factor analysis was used to identify the ecological processes occurring within the ponds and to construct a conceptual graphic model of the pond ecosystem functioning during the rainy and dry seasons. Processes related to nitrogen cycling presented differences between both seasons while processes related to phosphorus cycling did not. Ecological differences among ponds were due to effects of wind protection by surrounding vegetation, organic loading entering, tilapia density and its grazing pressure on zooplankton. Differences in tilapia growth among ponds were related to stocking density and ecological process affecting tilapia food availability and intraspecific competition. Lettuce wastes addition into the ponds did not produce negative effects, thus this practice may be considered a disposal option and a low-cost input source for tilapia, at least at the amounts applied in this study.

Study on each phase characteristics of the whole coal life cycle and their ecological risk assessment-a case of coal in China.

PubMed

Dai, Wenting; Dong, Jihong; Yan, Wanglin; Xu, Jiren

2017-01-01

The paper divided the whole coal life cycle, explained each phase characteristics, and took coal mine in China as a study case to assess the ecological risk in coal utilization phase. The main conclusions are as follows: (1) the whole coal life cycle is divided into coal mining, processing, transportation, utilization, and waste disposal. (2) The key points of production organization and characteristics in the five phases have great differences. The coal mining phase is characterized by the damage of the key ecological factors (water, soil, atmosphere, vegetation, etc.) damaged while the coal processing phase by discharging waste. The characteristics in coal transportation phase mainly performance as escaping and migration of atmospheric pollutants. In coal utilization phase, the main characteristics are aggravation of greenhouse effect. The main characteristics of waste disposal phase are accumulation of negative ecological effects on the land. (3) The ecological risk of soil heavy metals is serious in coal utilization phase. The potential ecological hazard coefficients of Pb and As in coal, residue and ash are all lower than 40, presenting low environmental impact on soil; the potential ecological risk coefficients of Cd are higher than 60, nearly half of their potential ecological risk coefficients are higher than 160, which presents high environmental pollution impact on soil; Hg's potential ecological risk coefficients are higher than 320, presenting the highest environmental pollution impact on soil; the comprehensive pollution indexes in coal, residue, and ash are relatively high, which means the pollution hazard potential to soil environment is high. (4) The ecological risk of the atmospheric solid suspended matter is relatively strong in coal utilization phase. The ecological risk of Cd and As in primary flue gas is both lower than net flue gas. The geoaccumulation indexes of Cd and Hg in primary flue gas and net flue gas are both higher than 5, presenting

Visual half-field presentations of incongruent color words: effects of gender and handedness.

PubMed

Franzon, M; Hugdahl, K

1986-09-01

Right-handed (dextral) and left-handed (sinistral) males and females (N = 15) were compared for language lateralization in a visual half-field (VHF) incongruent color-words paradigm. The paradigm consists of repeated brief (less than 200 msec) presentations of color-words written in an incongruent color. Presentations are either to the right or to the left of center fixation. The task of the subject is to report the color the word is written in on each trial, ignoring the color-word. Color-bars and congruent color-words were used as control stimuli. Vocal reaction time (VRT) and error frequency were used as dependent measures. The logic behind the paradigm is that incongruent color-words should lead to a greater cognitive conflict when presented in the half-field contralateral to the dominant hemisphere. The results showed significantly longer VRTs in the right half-field for the dextral subjects. Furthermore, significantly more errors were observed in the male dextral group when the incongruent stimuli were presented in the right half-field. There was a similar trend in the data for the sinistral males. No differences between half-fields were observed for the female groups. It is concluded that the present results strengthen previous findings from our laboratory (Hugdahl and Franzon, 1985) that the incongruent color-words paradigm is a useful non-invasive technique for the study of lateralization in the intact brain.

Socio-ecological influences on health-care access and navigation among persons of Mexican descent living on the U.S./Mexico border.

PubMed

Reininger, Belinda M; Barroso, Cristina S; Mitchell-Bennett, Lisa; Chavez, Marge; Fernandez, Maria E; Cantu, Ethel; Smith, Kirk L; Fisher-Hoch, Susan P

2014-04-01

The study reported here examines factors influencing decision-making concerning health care access and navigation among persons of Mexican origin living along the U.S./Mexico border. Specifically, the study examined how persons with limited financial resources accessed these two systems. Seven focus groups were held with 52 low income Mexican American people aged 18-65 years. Transcripts were analyzed to identify themes in Atlasti 5.0 software and the theory used included a socio-ecological framework and complemented by constructed from the Social Cognitive Theory. We found that in addition to a lack of insurance and financial resources to pay for health care; fear, embarrassment and denial associated with a diagnosis of illness; poor medical personnel interactions, and desire for quality but streamlined health care also influenced decision making. This theory-based study raises important issues if health care is to improve the health and welfare of disadvantaged populations and points to the need for greater focus on medical homes and prevention and early intervention approaches.

LibHalfSpace: A C++ object-oriented library to study deformation and stress in elastic half-spaces

NASA Astrophysics Data System (ADS)

Ferrari, Claudio; Bonafede, Maurizio; Belardinelli, Maria Elina

2016-11-01

The study of deformation processes in elastic half-spaces is widely employed for many purposes (e.g. didactic, scientific investigation of real processes, inversion of geodetic data, etc.). We present a coherent programming interface containing a set of tools designed to make easier and faster the study of processes in an elastic half-space. LibHalfSpace is presented in the form of an object-oriented library. A set of well known and frequently used source models (Mogi source, penny shaped horizontal crack, inflating spheroid, Okada rectangular dislocation, etc.) are implemented to describe the potential usage and the versatility of the library. The common interface given to library tools enables us to switch easily among the effects produced by different deformation sources that can be monitored at the free surface. Furthermore, the library also offers an interface which simplifies the creation of new source models exploiting the features of object-oriented programming (OOP). These source models can be built as distributions of rectangular boundary elements. In order to better explain how new models can be deployed some examples are included in the library.

Air pollution and case fatality of SARS in the People's Republic of China: an ecologic study

PubMed Central

Cui, Yan; Zhang, Zuo-Feng; Froines, John; Zhao, Jinkou; Wang, Hua; Yu, Shun-Zhang; Detels, Roger

2003-01-01

Background Severe acute respiratory syndrome (SARS) has claimed 349 lives with 5,327 probable cases reported in mainland China since November 2002. SARS case fatality has varied across geographical areas, which might be partially explained by air pollution level. Methods Publicly accessible data on SARS morbidity and mortality were utilized in the data analysis. Air pollution was evaluated by air pollution index (API) derived from the concentrations of particulate matter, sulfur dioxide, nitrogen dioxide, carbon monoxide and ground-level ozone. Ecologic analysis was conducted to explore the association and correlation between air pollution and SARS case fatality via model fitting. Partially ecologic studies were performed to assess the effects of long-term and short-term exposures on the risk of dying from SARS. Results Ecologic analysis conducted among 5 regions with 100 or more SARS cases showed that case fatality rate increased with the increment of API (case fatality = - 0.063 + 0.001 * API). Partially ecologic study based on short-term exposure demonstrated that SARS patients from regions with moderate APIs had an 84% increased risk of dying from SARS compared to those from regions with low APIs (RR = 1.84, 95% CI: 1.41–2.40). Similarly, SARS patients from regions with high APIs were twice as likely to die from SARS compared to those from regions with low APIs. (RR = 2.18, 95% CI: 1.31–3.65). Partially ecologic analysis based on long-term exposure to ambient air pollution showed the similar association. Conclusion Our studies demonstrated a positive association between air pollution and SARS case fatality in Chinese population by utilizing publicly accessible data on SARS statistics and air pollution indices. Although ecologic fallacy and uncontrolled confounding effect might have biased the results, the possibility of a detrimental effect of air pollution on the prognosis of SARS patients deserves further investigation. PMID:14629774

Ecology Based Decentralized Agent Management System

NASA Technical Reports Server (NTRS)

Peysakhov, Maxim D.; Cicirello, Vincent A.; Regli, William C.

2004-01-01

The problem of maintaining a desired number of mobile agents on a network is not trivial, especially if we want a completely decentralized solution. Decentralized control makes a system more r e bust and less susceptible to partial failures. The problem is exacerbated on wireless ad hoc networks where host mobility can result in significant changes in the network size and topology. In this paper we propose an ecology-inspired approach to the management of the number of agents. The approach associates agents with living organisms and tasks with food. Agents procreate or die based on the abundance of uncompleted tasks (food). We performed a series of experiments investigating properties of such systems and analyzed their stability under various conditions. We concluded that the ecology based metaphor can be successfully applied to the management of agent populations on wireless ad hoc networks.

Improved half-metallic gap of zincblende half-metal superlattices with the Tran-Blaha modified Becke-Johnson density functional

NASA Astrophysics Data System (ADS)

Guo, San-Dong

2016-08-01

Binary transition-metal pnictides and chalcogenides half-metallic ferromagnetic materials with zincblende structure, being compatible with current semiconductor technology, can be used to make high-performance spintronic devices. Here, we investigate electronic structures and magnetic properties of composite structure ((CrX)2 /(YX)2 (X=As, Sb; Se, Te and Y=Ga; Zn) superlattices) of zincblende half-metallic ferromagnetism and semiconductor by using Tran and Blaha's modified Becke and Johnson (mBJ) exchange potential. Calculated results show that they all are half-metallic ferromagnets with both generalized gradient approximation (GGA) and mBJ, and the total magnetic moment per formula unit follows a Slater-Pauling-like "rule of 8". The key half-metallic gaps by using mBJ are enhanced with respect to GGA results, which is because mBJ makes the occupied minority-spin p-bands move toward lower energy, but toward higher energy for empty minority-spin Cr-d bands. When the spin-orbit coupling (SOC) is included, the spin polarization deviates from 100%, and a most reduced polarization of 98.3% for (CrSb)2 /(GaSb)2, which indicates that SOC has small effects, of the order of 1%, in the considered four kinds of superlattice.

Physical Environments of Assisted Living: Research Needs and Challenges

ERIC Educational Resources Information Center

Cutler, Lois J.

2007-01-01

Purpose: This article aims to review research measures and findings related to physical environments of assisted living (AL) according to multiple conceptual perspectives--ecological, cultural, and Maslovian hierarchy. Design and Methods: A literature and research review was undertaken with two foci: performance measures for physical environments,…

Power converter for raindrop energy harvesting application: Half-wave rectifier

NASA Astrophysics Data System (ADS)

Izrin, Izhab Muhammad; Dahari, Zuraini

2017-10-01

Harvesting raindrop energy by capturing vibration from impact of raindrop have been explored extensively. Basically, raindrop energy is generated by converting the kinetic energy of raindrop into electrical energy by using polyvinylidene fluoride (PVDF) piezoelectric. In this paper, a power converter using half-wave rectifier for raindrop harvesting energy application is designed and proposed to convert damping alternating current (AC) generated by PVDF into direct current (DC). This research presents parameter analysis of raindrop simulation used in the experiment and resistive load effect on half-wave rectifier converter. The experiment is conducted by using artificial raindrop from the height of 1.3 m to simulate the effect of different resistive load on the output of half-wave rectifier converter. The results of the 0.68 MΩ resistive load showed the best performance of the half-wave rectifier converter used in raindrop harvesting energy system, which generated 3.18 Vaverage. The peak instantaneous output generated from this experiment is 15.36 µW.

Living with aliens: effects of invasive shrub honeysuckles on avian nesting.

PubMed

Gleditsch, Jason M; Carlo, Tomás A

2014-01-01

Invasive species have come to the forefront of conservation biology as a major threat to native biodiversity. Habitats dominated by shrub honeysuckles (Lonicera spp.) in the United States have been characterized as "ecological traps" by ecologists. Here we tested this hypothesis by investigating the effects of shrub honeysuckles on the nesting ecology of native birds in seven study sites in central Pennsylvania, USA. We examined how the abundance of shrub honeysuckles influenced the selection of nesting substrates and habitat for a community of common songbirds, and the parental-care behavior and nestling development of gray catbirds (Dumetella carolinensis). We found that birds had a strong bias towards nesting in honeysuckle shrubs, but not necessarily for nesting in honeysuckle-dominated habitats. Nest predation rates were affected by the density of nests in a habitat, but not by the overall abundance of honeysuckles in such habitats. Honeysuckle abundance in the habitat did show significant effects on some parental-care behavioral parameters: catbirds had higher nest visitation rates and shorter visit lengths in areas of high honeysuckle density. On average, Gray catbirds fed fruit 12%±0.31 s.e. of their nestling-feeding bouts, mostly fruits of shrub honeysuckles. Nestlings in sites with high honeysuckle density also showed higher mass:tarsus ratios, suggesting a good (possibly better) physiological condition of catbird nestlings at the time of fledging. Our study shows that honeysuckle-dominated habitats could have equivocal effects on nesting parameters of common species of native birds. We advise more caution in the widespread denomination of novel plant communities with high densities of honeysuckle as "ecological traps" as effects can be null or positive on native birds in certain localities.

Ecology, Microbial

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

Konopka, Allan

2009-05-15

Microbial ecology is a relatively young discipline within the field of microbiology. Its modern history spans just the past 60 years, and the field is defined by its emphasis on understanding the interactions of microbes with their environment, rather than their behavior under artificial laboratory conditions. Because microbes are ubiquitous, microbial ecologists study a broad diversity of habitats that range from aquatic to terrestrial to plant- or animal-associated. This has made it a challenge to identify unifying principles within the field. One approach is to recognize that although the activity of microbes in nature have effects at the macroscale, theymore » interact with their physical, chemical and biological milieu at a scale of micrometers. At this scale, several different microbial ecosystems can be defined, based upon association with particles, the presence of environmental gradients and the continuous availability of water. Principles applicable to microbial ecology reflect not only their population ecology and physiological ecology, but also their broad versatility and quantitative importance in the biosphere as biogeochemical catalysts and capacity for rapid physiological and evolutionary responses.« less

From Bathymetry to Bioshields: A Review of Post-Tsunami Ecological Research in India and its Implications for Policy

NASA Astrophysics Data System (ADS)

Mukherjee, Nibedita; Dahdouh-Guebas, Farid; Kapoor, Vena; Arthur, Rohan; Koedam, Nico; Sridhar, Aarthi; Shanker, Kartik

2010-09-01

More than half a decade has passed since the December 26th 2004 tsunami hit the Indian coast leaving a trail of ecological, economic and human destruction in its wake. We reviewed the coastal ecological research carried out in India in the light of the tsunami. In addition, we also briefly reviewed the ecological research in other tsunami affected countries in Asia namely Sri Lanka, Indonesia, Thailand and Maldives in order to provide a broader perspective of ecological research after tsunami. A basic search in ISI Web of Knowledge using keywords “tsunami” and “India” resulted in 127 peer reviewed journal articles, of which 39 articles were pertaining to ecological sciences. In comparison, Sri Lanka, Indonesia, Thailand and Maldives had, respectively, eight, four, 21 and two articles pertaining to ecology. In India, bioshields received the major share of scientific interest (14 out of 39) while only one study (each) was dedicated to corals, seagrasses, seaweeds and meiofauna, pointing to the paucity of research attention dedicated to these critical ecosystems. We noted that very few interdisciplinary studies looked at linkages between pure/applied sciences and the social sciences in India. In addition, there appears to be little correlation between the limited research that was done and its influence on policy in India. This review points to gap areas in ecological research in India and highlights the lessons learnt from research in other tsunami-affected countries. It also provides guidance on the links between science and policy that are required for effective coastal zone management.

Anti-influenza virus effects of both live and non-live Lactobacillus acidophilus L-92 accompanied by the activation of innate immunity.

PubMed

Goto, Hiroaki; Sagitani, Atsuhiro; Ashida, Nobuhisa; Kato, Shinji; Hirota, Tatsuhiko; Shinoda, Tadashi; Yamamoto, Naoyuki

2013-11-01

The antiviral effects of both a live and non-live Lactobacillus acidophilus strain L-92 (L-92) were investigated by oral administration (10 mg/mouse per d) daily for 21 d in a mouse model infected intranasally with influenza virus (H1N1). Virus titres in the lung of mice administered either live or non-live L-92 cells daily for 15 d were repressed 6 d after virus infection compared with the control group. Natural killer (NK) activity in the orally administered non-live L-92 group was higher compared with that of the control group before virus infection and on day 6. In contrast, NK activity in the live L-92 group compared with the control group was not significantly changed on both days, but was significantly higher on day 1. In contrast, live L-92 showed a greater repression of virus proliferation compared with non-live L-92, 6 d after the infection. Live L-92 decreased the number of neutrophils in the lung and suppressed lung weight, leading to the consequent deterioration of consolidation scores of the lung. These results indicated that pretreatment of live or non-live L-92 cells had protective effects against influenza virus infection. Among the measured cytokines and chemokines, eotaxin, macrophage colony-stimulating factor, IL-1b, RANTES (regulated on activation, normal T cell expressed and secreted) and interferon-a were significantly increased in the lung: IL-17 was significantly increased in Peyer’s patch of the live L-92 group compared with the control group. A mechanistic study suggested that the enhancement of NK activity in the lung caused by stimulating various antiviral cytokines and chemokines after the oral administration of L-92 cells might be important in protecting against virus infection.

7 CFR 51.2295 - Half kernel.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Half kernel. 51.2295 Section 51.2295 Agriculture... Standards for Shelled English Walnuts (Juglans Regia) Definitions § 51.2295 Half kernel. Half kernel means the separated half of a kernel with not more than one-eighth broken off. ...

Is xenodontine snake reproduction shaped by ancestry, more than by ecology?

PubMed

Bellini, Gisela P; Arzamendia, Vanesa; Giraudo, Alejandro R

2017-01-01

One of the current challenges of evolutionary ecology is to understand the effects of phylogenetic history (PH) and/or ecological factors (EF) on the life-history traits of the species. Here, the effects of environment and phylogeny are tested for the first time on the reproductive biology of South American xenodontine snakes. We studied 60% of the tribes of this endemic and most representative clade in a temperate region of South America. A comparative method (canonical phylogenetic ordination-CPO) was used to find the relative contributions of EF and PH upon life-history aspects of snakes, comparing the reproductive mode, mean fecundity, reproductive potential, and frequency of nearly 1,000 specimens. CPO analysis showed that PH or ancestry explained most of the variation in reproduction, whereas EF explained little of this variation. The reproductive traits under study are suggested to have a strong phylogenetic signal in this clade, the ancestry playing a big role in reproduction. The EF also influenced the reproduction of South American xenodontines, although to a lesser extent. Our finding provides new evidence of how the evolutionary history is embodied in the traits of living species.

Capillary reference half-cell

DOEpatents

Hall, Stephen H.

1996-01-01

The present invention is a reference half-cell electrode wherein intermingling of test fluid with reference fluid does not affect the performance of the reference half-cell over a long time. This intermingling reference half-cell may be used as a single or double junction submersible or surface reference electrode. The intermingling reference half-cell relies on a capillary tube having a first end open to reference fluid and a second end open to test fluid wherein the small diameter of the capillary tube limits free motion of fluid within the capillary to diffusion. The electrode is placed near the first end of the capillary in contact with the reference fluid. The method of operation of the present invention begins with filling the capillary tube with a reference solution. After closing the first end of the capillary, the capillary tube may be fully submerged or partially submerged with the second open end inserted into test fluid. Since the electrode is placed near the first end of the capillary, and since the test fluid may intermingle with the reference fluid through the second open end only by diffusion, this intermingling capillary reference half-cell provides a stable voltage potential for long time periods.

Capillary reference half-cell

DOEpatents

Hall, S.H.

1996-02-13

The present invention is a reference half-cell electrode wherein intermingling of test fluid with reference fluid does not affect the performance of the reference half-cell over a long time. This intermingling reference half-cell may be used as a single or double junction submersible or surface reference electrode. The intermingling reference half-cell relies on a capillary tube having a first end open to reference fluid and a second end open to test fluid wherein the small diameter of the capillary tube limits free motion of fluid within the capillary to diffusion. The electrode is placed near the first end of the capillary in contact with the reference fluid. The method of operation of the present invention begins with filling the capillary tube with a reference solution. After closing the first end of the capillary, the capillary tube may be fully submerged or partially submerged with the second open end inserted into test fluid. Since the electrode is placed near the first end of the capillary, and since the test fluid may intermingle with the reference fluid through the second open end only by diffusion, this intermingling capillary reference half-cell provides a stable voltage potential for long time periods. 11 figs.

Genotype × Herbivore Effect on Leaf Litter Decomposition in Betula Pendula Saplings: Ecological and Evolutionary Consequences and the Role of Secondary Metabolites

PubMed Central

Silfver, Tarja; Paaso, Ulla; Rasehorn, Mira; Rousi, Matti; Mikola, Juha

2015-01-01

Plant genetic variation and herbivores can both influence ecosystem functioning by affecting the quantity and quality of leaf litter. Few studies have, however, investigated the effects of herbivore load on litter decomposition at plant genotype level. We reduced insect herbivory using an insecticide on one half of field-grown Betula Pendula saplings of 17 genotypes, representing random intrapopulation genetic variation, and allowed insects to naturally colonize the other half. We hypothesized that due to induced herbivore defence, saplings under natural herbivory produce litter of higher concentrations of secondary metabolites (terpenes and soluble phenolics) and have slower litter decomposition rate than saplings under reduced herbivory. We found that leaf damage was 89 and 53% lower in the insecticide treated saplings in the summer and autumn surveys, respectively, which led to 73% higher litter production. Litter decomposition rate was also affected by herbivore load, but the effect varied from positive to negative among genotypes and added up to an insignificant net effect at the population level. In contrast to our hypothesis, concentrations of terpenes and soluble phenolics were higher under reduced than natural herbivory. Those genotypes, whose leaves were most injured by herbivores, produced litter of lowest mass loss, but unlike we expected, the concentrations of terpenes and soluble phenolics were not linked to either leaf damage or litter decomposition. Our results show that (1) the genetic and herbivore effects on B. pendula litter decomposition are not mediated through variation in terpene or soluble phenolic concentrations and suggest that (2) the presumably higher insect herbivore pressure in the future warmer climate will not, at the ecological time scale, affect the mean decomposition rate in genetically diverse B. pendula populations. However, (3) due to the significant genetic variation in the response of decomposition to herbivory, evolutionary

Storing data encoded DNA in living organisms

DOEpatents

Wong,; Pak C. , Wong; Kwong K. , Foote; Harlan, P [Richland, WA

2006-06-06

Current technologies allow the generation of artificial DNA molecules and/or the ability to alter the DNA sequences of existing DNA molecules. With a careful coding scheme and arrangement, it is possible to encode important information as an artificial DNA strand and store it in a living host safely and permanently. This inventive technology can be used to identify origins and protect R&D investments. It can also be used in environmental research to track generations of organisms and observe the ecological impact of pollutants. Today, there are microorganisms that can survive under extreme conditions. As well, it is advantageous to consider multicellular organisms as hosts for stored information. These living organisms can provide as memory housing and protection for stored data or information. The present invention provides well for data storage in a living organism wherein at least one DNA sequence is encoded to represent data and incorporated into a living organism.

Effects of Global Warming on Vibrio Ecology.

PubMed

Vezzulli, Luigi; Pezzati, Elisabetta; Brettar, Ingrid; Höfle, Manfred; Pruzzo, Carla

2015-06-01

Vibrio-related infections are increasing worldwide both in humans and aquatic animals. Rise in global sea surface temperature (SST), which is approximately 1 °C higher now than 140 years ago and is one of the primary physical impacts of global warming, has been linked to such increases. In this chapter, major known effects of increasing SST on the biology and ecology of vibrios are described. They include the effects on bacterial growth rate, both in the field and in laboratory, culturability, expression of pathogenicity traits, and interactions with aquatic organisms and abiotic surfaces. Special emphasis is given to the effect of ocean warming on Vibrio interactions with zooplankters, which represent one of the most important aquatic reservoirs for these bacteria. The reported findings highlight the biocomplexity of the interactions between vibrios and their natural environment in a climate change scenario, posing the need for interdisciplinary studies to properly understand the connection between ocean warming and persistence and spread of vibrios in sea waters and the epidemiology of the diseases they cause.

Predicting ecological effects of pollutants: A role for marine mesocosms

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

Ward, T.J.

1994-12-31

The major uncertainty in predicting the ecological effects of a pollutant is the relationship between dose and the ecological response. Mesocosms may be used to simulate population-level biological processes and to estimate the nature and shape of dose-related responses to pollutants, for use in predictive evaluations of pollutant impacts. To ensure that responses observed in mesocosm tests are representative it is necessary to confirm that the simulated processes operate at rates similar to those found in the field. Pilot experiments were conducted in small marine mesocosms simulating major processes in two local habitat types: unvegetated sand and sand colonized bymore » the brown macroalga Sargassum. The results showed that for a range of variates (such as the % of egg-bearing harpacticoid copepods, or the chlorophyll a concentration in surface sediments) the mean values for measurements in the tanks over a 9 week period did not consistently converge or diverge from those in the field. Also, for a number of the variates, a modelled decrease of more than about 60% in the mean could be detected with greater than 80% statistical power. This indicates that the effects of a pollutant could be detected with acceptable power. Use of a combination of such variates based on different functional or taxonomic groups for pollutant effects testing could greatly decrease uncertainty about the predicted effects of pollutants discharged to these habitats.« less

Handbook for Ecology Action.

ERIC Educational Resources Information Center

Eber, Ronald

This handbook has been compiled to aid concerned individuals and ecology groups more adequately define their goals, initiate good programs, and take effective action. It examines the ways a group of working individuals can become involved in action programs for ecological change. Part 1 deals with organization, preliminary organizing, structuring,…

Ecological Momentary Interventions: Incorporating Mobile Technology Into Psychosocial and Health Behavior Treatments

PubMed Central

Heron, Kristin E.; Smyth, Joshua M.

2009-01-01

Purpose Psychosocial and health behavior treatments and therapies can be extended beyond traditional research or clinical settings by using mobile technology to deliver interventions to individuals as they go about their daily lives. These Ecological Momentary Interventions [EMI] are treatments that are provided to people during their everyday lives (i.e., in real time) and in natural settings (i.e., real world). The goal of the present review is to synthesize and critique mobile technology-based EMI aimed at improving health behaviors and psychological and physical symptoms. Methods Twenty-seven interventions using palmtop computers or mobile phones to deliver ambulatory treatment for smoking cessation, weight loss, anxiety, diabetes management, eating disorders, alcohol use, and healthy eating and physical activity were identified. Results There is evidence that EMI can be successfully delivered, are accepted by patients, and are efficacious for treating a variety of health behaviors and physical and psychological symptoms. Limitations of the existing literature were identified and recommendations and considerations for research design, sample characteristics, measurement, statistical analyses, and clinical implementation are discussed. Conclusions Mobile technology-based EMI can be effectively implemented as interventions for a variety of health behaviors and psychological and physical symptoms. Future research should integrate the assessment and intervention capabilities of mobile technology to create dynamically and individually tailored EMI that are ecologically sensitive. PMID:19646331

Seeing the forest for the trees: hybridity and social-ecological symbols, rituals and resilience in postdisaster contexts

Treesearch

Keith G. Tidball

2014-01-01

The role of community-based natural resources management in the form of "greening" after large scale system shocks and surprises is argued to provide multiple benefits via engagement with living elements of social-ecological systems and subsequent enhanced resilience at multiple scales. The importance of so-called social-ecological symbols, especially the...

Nursing home prices and market structure: the effect of assisted living industry expansion.

PubMed

Bowblis, John R

2014-01-01

Since the 1990s, there has been substantial expansion of facility-based alternatives to nursing home care, such as assisted living facilities. This paper analyzes the relationship between expansion of the assisted living industry, nursing home market structure and nursing home private pay prices using a two-year panel of nursing homes in the State of Ohio. Fixed effect regressions suggest that the expansion of assisted living facilities are associated with increased nursing home concentration, but find no effect on private pay nursing home prices. This would be consistent with assisted livings reducing demand for nursing homes by delaying entry into a nursing home, though assisted livings are not direct competitors of nursing homes.

Ecological planning of urbanized areas in the south of the Far East (Birobidzhan city as an example)

NASA Astrophysics Data System (ADS)

Kalmanova, V. B.

2018-01-01

Ecological planning of urbanized areas is an urgent demand of the time, because more than 70% of Russia’s population lives in cities. The article describes that the city’s ecological planning is an important part of the area’s organization in its development strategy. The principles and features of the urban area’s ecological organization are proposed. The basis for environmental planning is the ecological and functional zoning of urban areas. The algorithm of ecological-functional zoning is developed to optimize the quality of the urban environment. Based on it, it is possible to identify the planning structure’s features, justify anthropogenic pressure on the natural components of the urban environment, etc. The article briefly presents the possibility of using the main conditions of the ecological framework in the planning of urban areas. Considering the perspective trends of the formation and development of cities in the south of the Far East, the ecological problems caused by regional natural and anthropogenic causes (features of relief, climate, functional-planning structure) are considered. The need for environmental planning of cities in the south of the Far East is shown. The results of the ecological framework’s formation of Birobidzhan city based on its ecological and functional zoning are described. The total area of open unreformed spaces in the city is calculated to be 60.8%, which can serve as the main elements of the ecological framework and perspective reserve areas for ecological planning. The cartographic model of Birobidzhan’s ecological framework is presented, which is the result and model of this type of planning. The practical use of the proposed model will facilitate the adoption of effective management decisions aimed at stabilized development of the city.

Ecological and Evolutionary Effects of Dispersal on Freshwater Zooplankton

ERIC Educational Resources Information Center

Allen, Michael R.

2009-01-01

A recent focus on contemporary evolution and the connections between communities has sought to more closely integrate ecology with evolutionary biology. Studies of coevolutionary dynamics, life history evolution, and rapid local adaptation demonstrate that ecological circumstances can dictate evolutionary trajectories. Thus, variation in species…

An analytically tractable model for community ecology with many species

NASA Astrophysics Data System (ADS)

Dickens, Benjamin; Fisher, Charles; Mehta, Pankaj; Pankaj Mehta Biophysics Theory Group Team

A fundamental problem in community ecology is to understand how ecological processes such as selection, drift, and immigration yield observed patterns in species composition and diversity. Here, we present an analytically tractable, presence-absence (PA) model for community assembly and use it to ask how ecological traits such as the strength of competition, diversity in competition, and stochasticity affect species composition in a community. In our PA model, we treat species as stochastic binary variables that can either be present or absent in a community: species can immigrate into the community from a regional species pool and can go extinct due to competition and stochasticity. Despite its simplicity, the PA model reproduces the qualitative features of more complicated models of community assembly. In agreement with recent work on large, competitive Lotka-Volterra systems, the PA model exhibits distinct ecological behaviors organized around a special (``critical'') point corresponding to Hubbell's neutral theory of biodiversity. Our results suggest that the concepts of ``phases'' and phase diagrams can provide a powerful framework for thinking about community ecology and that the PA model captures the essential ecological dynamics of community assembly. Pm was supported by a Simons Investigator in the Mathematical Modeling of Living Systems and a Sloan Research Fellowship.

The effects of patch shape on indigo buntings. Evidence for an ecological trap

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

Weldon, Aimee J.; Haddad, Nick M.

2005-01-01

Weldon, Aimee, J., and Nick M. Haddad. 2005. The effect of patch shape on indigo buntings: Evidence for an ecological trap. Ecology 86(6):1422-1431. Abstract. Habitat loss and fragmentation have led to a widespread increase in the proportion of edge habitat in the landscape. Disturbance-dependent bird species are widely assumed to benefit from these edges. However, anthropogenic edges may concentrate nest predators while retaining habitat cues that birds use to select breeding habitat. This may lead birds to mistakenly select dangerous habitat a phenomenon known as an ecological trap. We experimentally demonstrated how habitat shape, and thus amount of edge, canmore » adversely affect nest site selection and reproductive success of a disturbance-dependent bird species, the Indigo Bunting (Passerina cyanea). We did so within a landscape-scale experiment composed of equal-area habitat patches that differed in their amount of edge. Indigo Buntings preferentially selected edgy patches, which contained 50% more edge than more compact rectangular patches. Further, buntings fledged significantly fewer young per pair in edgy patches than in rectangular patches. These results provide the first experimental evidence that edges can function as ecological traps.« less

Parasites and marine invasions: Ecological and evolutionary perspectives

NASA Astrophysics Data System (ADS)

Goedknegt, M. Anouk; Feis, Marieke E.; Wegner, K. Mathias; Luttikhuizen, Pieternella C.; Buschbaum, Christian; Camphuysen, Kees (C. J.); van der Meer, Jaap; Thieltges, David W.

2016-07-01

Worldwide, marine and coastal ecosystems are heavily invaded by introduced species and the potential role of parasites in the success and impact of marine invasions has been increasingly recognized. In this review, we link recent theoretical developments in invasion ecology with empirical studies from marine ecosystems in order to provide a conceptual framework for studying the role of parasites and their hosts in marine invasions. Based on an extensive literature search, we identified six mechanisms in which invaders directly or indirectly affect parasite and host populations and communities: I) invaders can lose some or all of their parasites during the invasion process (parasite release or reduction), often causing a competitive advantage over native species; II) invaders can also act as a host for native parasites, which may indirectly amplify the parasite load of native hosts (parasite spillback); III) invaders can also be parasites themselves and be introduced without needing co-introduction of the host (introduction of free-living infective stages); IV) alternatively, parasites may be introduced together with their hosts (parasite co-introduction with host); V) consequently, these co-introduced parasites can sometimes also infect native hosts (parasite spillover); and VI) invasive species may be neither a host nor a parasite, but nevertheless affect native parasite host interactions by interfering with parasite transmission (transmission interference). We discuss the ecological and evolutionary implications of each of these mechanisms and generally note several substantial effects on natural communities and ecosystems via i) mass mortalities of native populations creating strong selection gradients, ii) indirect changes in species interactions within communities and iii) trophic cascading and knock-on effects in food webs that may affect ecosystem function and services. Our review demonstrates a wide range of ecological and evolutionary implications of

Framework for Ecological Risk Assessment

EPA Pesticide Factsheets

This is the first step in a long-term effort to develop risk assessment guidelines for ecological effects. Its primary purpose is to offer a simple, flexible structure for conducting and evaluating ecological risk assessment within EPA.

Detection of Extraterrestrial Ecology (Exoecology)

NASA Technical Reports Server (NTRS)

Jones, Harry; DeVincenzi, Donald L. (Technical Monitor)

2000-01-01

Researchers in the Astrobiology Technology Branch at Ames Research Center have begun investigating alternate concepts for the detection of extraterrestrial life. We suggest searching for extraterrestrial ecology, exoecology, as well as for extraterrestrial biology, exobiology. Ecology describes the interactions of living things with their environment. All ecosystems are highly constrained by their environment and are constrained by well-known system design principles. Ecology could exist wherever there is an energy source and living I things have discovered some means to capture, store, and use the available energy. Terrestrial ecosystems use as energy sources, light, organic molecules, and in thermal vents and elsewhere, simple inorganic molecules. Ecosystem behavior is controlled by matter and energy conservation laws and can be described by linear and nonlinear dynamic systems theory. Typically in an ecosystem different molecules are not in chemical equilibrium and scarce material is conserved, stored, or recycled. Temporal cycles and spatial variations are often observed. These and other -eneral principles of exoecology can help guide the search for extraterrestrial life. The chemical structure observed in terrestrial biology may be highly contingent on evolutionary accidents. Oxygen was not always abundant on Earth. Primitive sulfur bacteria use hydrogen sulfide and sulfur to perform photosynthesis instead of water and oxygen. Astrobiologists have assumed, for the sake of narrowing and focusing our life detection strategies, that extraterrestrial life will have detailed chemical similarities with terrestrial life. Such assumptions appear very reasonable and they allow us to design specific and highly sensitive life detection experiments. But the fewer assumptions we make, the less chance we have of being entirely wrong The best strategy for the detection of extraterrestrial life could be a mixed strategy. We should use detailed assumptions based on terrestrial

Where the Wild Things Are: Informal Experience and Ecological Reasoning

ERIC Educational Resources Information Center

Coley, John D.

2012-01-01

Category-based induction requires selective use of different relations to guide inferences; this article examines the development of inferences based on ecological relations among living things. Three hundred and forty-six 6-, 8-, and 10-year-old children from rural, suburban, and urban communities projected novel "diseases" or "insides" from one…

An Ecological Perspective on the Media and Youth Development

PubMed Central

McHale, Susan M.; Dotterer, Aryn; Kim, Ji-Yeon

2011-01-01

From an ecological perspective, daily activities are both a cause and a consequence of youth development. Research on youth activities directs attention to the processes through which daily activities may have an impact on youth, including: (a) providing chances to learn and practice skills; (b) serving as a forum for identity development; (c) affording opportunities to build social ties; (d) connecting youth to social institutions; and (e) keeping youth from engaging in other kinds of activities. Youth’s daily activities, in turn, both influence and are influenced by the multi-layered ecology within which their lives are embedded, an ecology that ranges from the proximal contexts of everyday life (e.g., family, peer group) to the larger political, economic, legal and cultural contexts of the larger society. The paper concludes with consideration of methodological issues and directions for research on the media and youth development. PMID:22247564

An Ecological Perspective on the Media and Youth Development.

PubMed

McHale, Susan M; Dotterer, Aryn; Kim, Ji-Yeon

2009-04-01

From an ecological perspective, daily activities are both a cause and a consequence of youth development. Research on youth activities directs attention to the processes through which daily activities may have an impact on youth, including: (a) providing chances to learn and practice skills; (b) serving as a forum for identity development; (c) affording opportunities to build social ties; (d) connecting youth to social institutions; and (e) keeping youth from engaging in other kinds of activities. Youth's daily activities, in turn, both influence and are influenced by the multi-layered ecology within which their lives are embedded, an ecology that ranges from the proximal contexts of everyday life (e.g., family, peer group) to the larger political, economic, legal and cultural contexts of the larger society. The paper concludes with consideration of methodological issues and directions for research on the media and youth development.

Short Lived Fission Product Yield Measurements in 235U, 238U and 239Pu

NASA Astrophysics Data System (ADS)

Silano, Jack; Tonchev, Anton; Tornow, Werner; Krishichayan, Fnu; Finch, Sean; Gooden, Matthew; Wilhelmy, Jerry

2017-09-01

Yields of short lived fission products (FPYs) with half lives of a few minutes to an hour contain a wealth of information about the fission process. Knowledge of short lived FPYs would contribute to existing data on longer lived FPY mass and charge distributions. Of particular interest are the relative yields between the ground states and isomeric states of FPYs since these isomeric ratios can be used to determine the angular momentum of the fragments. Over the past five years, a LLNL-TUNL-LANL collaboration has made precision measurements of FPYs from quasi-monoenergetic neutron induced fission of 235U, 238U and 239Pu. These efforts focused on longer lived FPYs, using a well characterized dual fission chamber and several days of neutron beam exposure. For the first time, this established technique will be applied to measuring short lived FPYs, with half lives of minutes to less than an hour. A feasibility study will be performed using irradiation times of < 1 hour, improving the sensitivity to short lived FPYs by limiting the buildup of long lived isotopes. Results from this exploratory study will be presented, and the implications for isomeric ratio measurements will be discussed. This work was performed under the auspices of US DOE by LLNL under Contract DE-AC52-07NA27344.

Effects on Calculated Half-Widths and Shifts from the Line Coupling for Asymmetric-Top Molecules

NASA Technical Reports Server (NTRS)

Ma, Q.; Boulet, C.; Tipping, R. H.

2014-01-01

The refinement of the Robert-Bonamy formalism by considering the line coupling for linear molecules developed in our previous studies [Q. Ma, C. Boulet, and R. H. Tipping, J. Chem. Phys. 139, 034305 (2013); 140, 104304 (2014)] have been extended to asymmetric-top molecules. For H2O immersed in N2 bath, the line coupling selection rules applicable for the pure rotational band to determine whether two specified lines are coupled or not are established. Meanwhile, because the coupling strengths are determined by relative importance of off-diagonal matrix elements versus diagonal elements of the operator -iS1 -S2, quantitative tools are developed with which one is able to remove weakly coupled lines from consideration. By applying these tools, we have found that within reasonable tolerances, most of the H2O lines in the pure rotational band are not coupled. This reflects the fact that differences of energy levels of the H2O states are pretty large. But, there are several dozen strongly coupled lines and they can be categorized into different groups such that the line couplings occur only within the same groups. In practice, to identify those strongly coupled lines and to confine them into sub-linespaces are crucial steps in considering the line coupling. We have calculated half-widths and shifts for some groups, including the line coupling. Based on these calculations, one can conclude that for most of the H2O lines, it is unnecessary to consider the line coupling. However, for several dozens of lines, effects on the calculated half-widths from the line coupling are small, but remain noticeable and reductions of calculated half-widths due to including the line coupling could reach to 5%. Meanwhile, effects on the calculated shifts are very significant and variations of calculated shifts could be as large as 25%.

An index of ecological integrity for the Mississippi alluvial plain ecoregion: index development and relations to selected landscape variables

USGS Publications Warehouse

Justus, B.G.

2003-01-01

Macroinvertebrate community, fish community, water-quality, and habitat data collected from 36 sites in the Mississippi Alluvial Plain Ecoregion during 1996-98 by the U.S. Geological Survey were considered for a multimetric test of ecological integrity. Test metrics were correlated to site scores of a Detrended Correspondence Analysis of the fish community (the biological community that was the most statistically significant for indicating ecological conditions in the ecoregion) and six metrics--four fish metrics, one chemical metric (total ammonia plus organic nitrogen) and one physical metric (turbidity)--having the highest correlations were selected for the index. Index results indicate that sites in the northern half of the study unit (in Arkansas and Missouri) were less degraded than sites in the southern half of the study unit (in Louisiana and Mississippi). Of 148 landscape variables evaluated, the percentage of Holocene deposits and cotton insecticide rates had the highest correlations to index of ecological integrity results. sites having the highest (best) index scores had the lowest percentages of Holocene deposits and the lowest cotton insecticide use rates, indicating that factors relating to the amount of Holocene deposits and cotton insecticide use rates partially explain differences in ecological conditions throughout the Mississippi Alluvial Plain Ecoregion.

The real ecological fallacy: epidemiology and global climate change.

PubMed

Krieger, Nancy

2015-08-01

Prompted by my participation in the People's Climate March held in New York City on 21 September 2014, as part of the 'Harvard Divest' contingent, in this brief essay I reflect on the late 20th century development of--and debates over--the necessity of ecological thinking in epidemiology, and also the still limited engagement of our field with work on the health impact of global climate change. Revisiting critiques about the damaging influence of methodological individualism on our field, I extend critique of the still influential notion of 'ecological fallacy,' including its wilful disregard for ecology itself as being pertinent to people's ways of living--and dying. Indeed, the real 'ecological fallacy' is to think epidemiologists or others could ever understand the people's health except in societal and ecological, and hence historical, context. I conclude by urging all of us, as members of the broader scientific community, whether or not we directly study the health impacts of the planetary emergency of global climate change, to step up by joining the call for universities to divest from fossil fuels. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Campground marketing: the heavy-half strategy

Treesearch

Wilbur F. LaPage

1969-01-01

When we arrayed camping frequencies in order from the lowest to the highest number of days spent camping per year we found that half of the campers do much more than half of the camping. Campers in this heavy half consistently camp more, year after year, and are increasing their annual participation as well. Heavy-half campers have larger investments in camping...

Assessment of ecological passages along road networks within the Mediterranean forest using GIS-based multi criteria evaluation approach.

PubMed

Gülci, Sercan; Akay, Abdullah Emin

2015-12-01

Major roads cause barrier effect and fragmentation on wildlife habitats that are suitable places for feeding, mating, socializing, and hiding. Due to wildlife collisions (Wc), human-wildlife conflicts result in lost lives and loss of biodiversity. Geographical information system (GIS)-based multi criteria evaluation (MCE) methods have been successfully used in short-term planning of road networks considering wild animals. Recently, wildlife passages have been effectively utilized as road engineering structures provide quick and certain solutions for traffic safety and wildlife conservation problems. GIS-based MCE methods provide decision makers with optimum location for ecological passages based on habitat suitability models (HSMs) that classify the areas based on ecological requirements of target species. In this study, ecological passages along Motorway 52 within forested areas in Mediterranean city of Osmaniye in Turkey were evaluated. Firstly, HSM coupled with nine eco-geographic decision variables were developed based on ecological requirements of roe deer (Capreolus capreolus) that were chosen as target species. Then specified decision variables were evaluated using GIS-based weighted linear combination (WLC) method to estimate movement corridors and mitigation points along the motorway. In the solution process, two linkage nodes were evaluated for eco-passages which were determined based on the least-cost movement corridor intersecting with the motorway. One of the passages was identified as a natural wildlife overpass while the other was suggested as underpass construction. The results indicated that computer-based models provide accurate and quick solutions for positioning ecological passages to reduce environmental effects of road networks on wild animals.

Microbial ecology of the closed artificial ecosystem MELiSSA (Micro-Ecological Life Support System Alternative): reinventing and compartmentalizing the Earth's food and oxygen regeneration system for long-haul space exploration missions.

PubMed

Hendrickx, Larissa; De Wever, Heleen; Hermans, Veronik; Mastroleo, Felice; Morin, Nicolas; Wilmotte, Annick; Janssen, Paul; Mergeay, Max

2006-01-01

MELiSSA is a bioregenerative life support system designed by the European Space Agency (ESA) for the complete recycling of gas, liquid and solid wastes during long distance space exploration. The system uses the combined activity of different living organisms: microbial cultures in bioreactors, a plant compartment and a human crew. In this minireview, the development of a short-cut ecological system for the biotransformation of organic waste is discussed from a microorganism's perspective. The artificial ecological model--still in full development--that is inspired by Earth's own geomicrobiological ecosystem serves as an ideal study object on microbial ecology and will become an indispensable travel companion in manned space exploration.

The Effects of the Living Together through Art (LTTA) Model on Promoting the Consciousness of Living Together between Thai and Migrant Students

ERIC Educational Resources Information Center

Juaseekoon, Sarita; Pholprasert, Apichart; Rukspollmuang, Chanita

2017-01-01

The aim of this research is to study the effects of the Living Together through Art model (LTTA model), a newly developed art learning model based on the concept of UNESCO's "Learning to Live Together", on promoting the consciousness of living together between Thai and migrant students which consisted of 4 core values: respect,…

Sex- and age-related differences in half-marathon performance and competitiveness in the world's largest half-marathon - the GöteborgsVarvet.

PubMed

Knechtle, B; Nikolaidis, P T

2018-01-01

In road runners, the age-related performance decline has been well investigated for marathoners, but little is known for half-marathoners. We analysed data from 138,616 runners (48,148 women and 90,469 men) competing between 2014 and 2016 in GöteborgsVarvet, the world's largest half-marathon. The men-to-women ratio in participants increased with age, the fastest race times were observed in age groups ˂35 and 35-39 years in women and in age group 35-39 years in men, the main effect of sex and the sex × age group interaction on race time were trivial, and the competitiveness was denser in men and in the younger age groups. In summary, in half-marathon running in the largest half-marathon in the world, the GöteborgsVarvet, women achieved the fastest race time at an earlier age compared to men where the fastest race times were observed in women in age groups ˂35 and 35-39 years and in men in age group 35-39 years.

The role of adaptive immunity as an ecological filter on the gut microbiota in zebrafish.

PubMed

Stagaman, Keaton; Burns, Adam R; Guillemin, Karen; Bohannan, Brendan Jm

2017-07-01

All animals live in intimate association with communities of microbes, collectively referred to as their microbiota. Certain host traits can influence which microbial taxa comprise the microbiota. One potentially important trait in vertebrate animals is the adaptive immune system, which has been hypothesized to act as an ecological filter, promoting the presence of some microbial taxa over others. Here we surveyed the intestinal microbiota of 68 wild-type zebrafish, with functional adaptive immunity, and 61 rag1 - zebrafish, lacking functional B- and T-cell receptors, to test the role of adaptive immunity as an ecological filter on the intestinal microbiota. In addition, we tested the robustness of adaptive immunity's filtering effects to host-host interaction by comparing the microbiota of fish populations segregated by genotype to those containing both genotypes. The presence of adaptive immunity individualized the gut microbiota and decreased the contributions of neutral processes to gut microbiota assembly. Although mixing genotypes led to increased phylogenetic diversity in each, there was no significant effect of adaptive immunity on gut microbiota composition in either housing condition. Interestingly, the most robust effect on microbiota composition was co-housing within a tank. In all, these results suggest that adaptive immunity has a role as an ecological filter of the zebrafish gut microbiota, but it can be overwhelmed by other factors, including transmission of microbes among hosts.

Epidemiology and Ecology of Tularemia in Sweden, 1984–2012

PubMed Central

Desvars, Amélie; Furberg, Maria; Hjertqvist, Marika; Vidman, Linda; Sjöstedt, Anders; Rydén, Patrik

2015-01-01

The zoonotic disease tularemia is endemic in large areas of the Northern Hemisphere, but research is lacking on patterns of spatial distribution and connections with ecologic factors. To describe the spatial epidemiology of and identify ecologic risk factors for tularemia incidence in Sweden, we analyzed surveillance data collected over 29 years (1984–2012). A total of 4,830 cases were notified, of which 3,524 met all study inclusion criteria. From the first to the second half of the study period, mean incidence increased 10-fold, from 0.26/100,000 persons during 1984–1998 to 2.47/100,000 persons during 1999–2012 (p<0.001). The incidence of tularemia was higher than expected in the boreal and alpine ecologic regions (p<0.001), and incidence was positively correlated with the presence of lakes and rivers (p<0.001). These results provide a comprehensive epidemiologic description of tularemia in Sweden and illustrate that incidence is higher in locations near lakes and rivers. PMID:25529978

Transmutation of skyrmions to half-solitons driven by the nonlinear optical spin Hall effect.

PubMed

Flayac, H; Solnyshkov, D D; Shelykh, I A; Malpuech, G

2013-01-04

We show that the spin domains, generated in the linear optical spin Hall effect by the analog of spin-orbit interaction for exciton polaritons, are associated with the formation of a Skyrmion lattice. In the nonlinear regime, the spin anisotropy of the polariton-polariton interactions results in a spatial compression of the domains and in a transmutation of the Skyrmions into oblique half-solitons. This phase transition is associated with both the focusing of the spin currents and the emergence of a strongly anisotropic emission pattern.

Workshop on Closed System Ecology

NASA Technical Reports Server (NTRS)

1982-01-01

Self maintaining laboratory scale ecological systems completely isolated from exchanges of matter with external systems were demonstrated. These research tools are discussed in terms of their anticipated value in understanding (1) global ecological material and energy balances, (2) the dynamics of stability and instability in ecosystems, (3) the effects of man-made substances and structures on ecosystems, and (4) the precise requirements for dynamic control of controlled ecology life support systems (CELSS).

A Conceptual Model for Teaching the Relationship of Daily Life and Human Environmental Impact to Ecological Function

ERIC Educational Resources Information Center

Wyner, Yael

2013-01-01

In the general activity of daily life, it is easy to miss our dependency on the Earth's ecology. At the same time that people are living apparently separate from the environment, our impact on the Earth is increasing. This study seeks to understand how teachers can bridge this persistent disconnect of daily life from ecology and human impact.…

Basic Methods for the Study of Reproductive Ecology of Fish in Aquaria.

PubMed

Fukuda, Kazuya; Sunobe, Tomoki

2017-07-20

Captive-rearing observations are valuable for revealing aspects of fish behavior and ecology when continuous field investigations are impossible. Here, a series of basic techniques are described to enable observations of the reproductive behavior of a wild-caught gobiid fish, as a model, kept in an aquarium. The method focuses on three steps: collection, transport, and observations of reproductive ecology of a substrate spawner. Essential aspects of live fish collection and transport are (1) preventing injury to the fish, and (2) careful acclimation to the aquarium. Preventing harm through injuries such as scratches or a sudden change of water pressure is imperative when collecting live fish, as any physical damage is likely to negatively affect the survival and later behavior of the fish. Careful acclimation to aquaria decreases the incidence death and mitigates the shock of transport. Observations during captive rearing include (1) the identification of individual fish and (2) monitoring spawned eggs without negative effects to the fish or eggs, thereby enabling detailed investigation of the study species' reproductive ecology. The subcutaneous injection of a visible implant elastomer (VIE) tag is a precise method for the subsequent identification of individual fish, and it can be used with a wide size range of fish, with minimal influence on their survival and behavior. If the study species is a substrate spawner that deposits adhesive eggs, an artificial nest site constructed from polyvinyl chloride (PVC) pipe with the addition of a removable waterproof sheet will facilitate counting and monitoring the eggs, lessening the investigator's influence on the nest-holding and egg-guarding behavior of the fish. Although this basic method entails techniques that are seldom mentioned in detail in research articles, they are fundamental for undertaking experiments that require the captive rearing of a wild fish.

[Evaluation on a demonstration project of ecological restoration of ditches at Qianwei Village of Chongming County, Shanghai].

PubMed

Zhou, Xiang-Xiang; Zhang, Li-Quan; Yuan, Lian-Qi

2008-02-01

By using biological slope-protection techniques, oxidation pond system, and zeolite treatment system, a demonstration project of ecological restoration of ditches at the Qianwei Village of Chongming County in Shanghai was implemented, and an evaluation on the project was made via a runoff simulation experiment and the measurements of the parameters soil shear strength, biodiversity, and ditch water quality. The results showed that covering the dich slopes with shrub could significantly increase soil shear strength, compactness and moisture content, and the formed vegetation had significant effects on retarding runoff and removing TSS (P < 0.05). Applying live fascines could significantly increase soil shear strength and TSS removal rate (P < 0.05), but its effects on increasing soil compactness and moisture content and retaining runoff were not significant. After the implement of the demonstration project, the total N and P concentrations in ditch water decreased significantly, habitat quality and aesthetic value of ditch slope improved, and biodiversity enhanced greatly. The integration of the biological techniques with other ecological restoration measures could stabilize ditch slope, improve ditch habitat quality, and restore the ecological environment of the ditches.

ecological geological maps: GIS-based evaluation of the Geo-Ecological Quality Index (GEQUI) in Sicily (Central Mediterranean)

NASA Astrophysics Data System (ADS)

Nigro, Fabrizio; Arisco, Giuseppe; Perricone, Marcella; Renda, Pietro; Favara, Rocco

2010-05-01

synthetic way. The first, characterized or estimated, prognosticated one or several indexes of geological ecological conditions. In the second type of maps, the whole complex is reflected, which defined the modern or prognosticable ecological geological situation. Regarding the ecological geological zoning maps, the contemporary state of ecological geological conditions may be evaluated by a range of parameters into classes of conditions and, on the basis of these informations, the estimation from the position of comfort and safety of human life and function of ecosystem is given. Otherwise, the concept of geoecological land evaluation has become established in the study of landscape/environmental plannings in recent years. It requires different thematic data-sets, deriving from the natural-, social- and amenity-environmental resources analysis, that may be translate in environmental (vulnerability/quality) indexes. There have been some attempts to develop integrated indices related to various aspects of the environment within the framework of sustainable development (e.g.: United Nations Commission on Sustainable Development, World Economic Forum, Advisory Board on Indicators of Sustainable Development of the International Institute for Sustainable Development, Living Planet Index established by the World Wide Fund for Nature, etc.). So, the ecological geological maps represent the basic tool for the geoecological land evaluation policies and may be computed in terms of index-maps. On these basis, a GIS application for assessing the ecological geological zoning is presented for Sicily (Central Mediterranean). The Geo-Ecological Quality Index (GEQUI) map was computed by considering a lot of variables. Ten variables (lithology, climate, landslide distribution, erosion rate, soil type, land cover, habitat, groundwater pollution, roads density and buildings density) generated from available data, were used in the model, in which weighting values to each informative layer were

75 FR 8338 - EPA Science Advisory Board Staff Office Notification of a Meeting of the Ecological Effects...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-24

... the Second Section 812 Benefit-Cost Analysis of the Clean Air Act. The assessment of ecological... Analysis of the benefits and costs of the Clean Air Act. DATES: The EES augmented with additional experts... ecological effects of modeled air quality scenarios developed to support the Second Section 812 Benefit-Cost...

Ecology for a crowded planet

USGS Publications Warehouse

Palmer, Margaret; Bernhardt, Emily S.; Chornesky, Elizabeth A.; Collins, Scott L.; Dobson, Andrew; Duke, Clifford; Gold, Barry; Jacobson, Robert; Kingsland, Sharon E.; Kranz, Rhonda H.; Mappin, Michael J.; Martinez, M. Luisa; Micheli, Fiorenza; Morse, Jennifer L.; Pace, Michael L.; Pascual, Mercedes; Palumbi, Stephen S.; Reichman, O. J.; Simons, Ashley; Townsend, Alan R.; Turner, Monica

2004-01-01

Within the next 50 to 100 years, the support and maintenance of an extended human family of 8 to 11 billion people will be difficult at best. The authors of this Policy Forum describe changes that are required if we hope to meet the needs and aspirations of humans while improving the health of our planet's ecosystems. Problems as diverse as disease transmission and global climate change have benefited substantially from advances in ecology. Such advances have set the stage for emergence of a proactive ecological science in which social and political realities are acknowledged and attention is turned decisively toward the future. The ecological sciences must chart an understanding of how ecosystem services can persist given their extensive human use. Innovative research on the sciences of ecosystem services, ecological restoration, and ecological design must be massively accelerated and must be accompanied by more effective communication of ecological knowledge to society.

LED and Semiconductor Photo-effects on Living Things

NASA Astrophysics Data System (ADS)

Fujiyasu, Hiroshi; Ishigaki, Takemitsu; Fujiyasu, Kentarou; Ujihara, Shirou; Watanabe, Naoharu; Sunayama, Shunji; Ikoma, Shuuji

We have studied LED irradiation effects on plants and animals in the visible to UV region of light from GaN LEDs. The results are as follows. Blue light considers to be effective for pearl cultivation or for attraction of small fishes living in near the surface of sea such as Pompano or Sardine, white light radiation is effective for cultivation of botanical plankton for shells. Other experiments of UV light irradiation attracting effect on baby sea turtle and the germination UV effect of mushroom, green light weight enhance effect on baby pigs, light vernalization effect of vegitable and Ge far infrared therapic effect on human body are also given.

Increasing connectivity between metapopulation ecology and landscape ecology.

PubMed

Howell, Paige E; Muths, Erin; Hossack, Blake R; Sigafus, Brent H; Chandler, Richard B

2018-05-01

Metapopulation ecology and landscape ecology aim to understand how spatial structure influences ecological processes, yet these disciplines address the problem using fundamentally different modeling approaches. Metapopulation models describe how the spatial distribution of patches affects colonization and extinction, but often do not account for the heterogeneity in the landscape between patches. Models in landscape ecology use detailed descriptions of landscape structure, but often without considering colonization and extinction dynamics. We present a novel spatially explicit modeling framework for narrowing the divide between these disciplines to advance understanding of the effects of landscape structure on metapopulation dynamics. Unlike previous efforts, this framework allows for statistical inference on landscape resistance to colonization using empirical data. We demonstrate the approach using 11 yr of data on a threatened amphibian in a desert ecosystem. Occupancy data for Lithobates chiricahuensis (Chiricahua leopard frog) were collected on the Buenos Aires National Wildlife Refuge (BANWR), Arizona, USA from 2007 to 2017 following a reintroduction in 2003. Results indicated that colonization dynamics were influenced by both patch characteristics and landscape structure. Landscape resistance increased with increasing elevation and distance to the nearest streambed. Colonization rate was also influenced by patch quality, with semi-permanent and permanent ponds contributing substantially more to the colonization of neighboring ponds relative to intermittent ponds. Ponds that only hold water intermittently also had the highest extinction rate. Our modeling framework can be widely applied to understand metapopulation dynamics in complex landscapes, particularly in systems in which the environment between habitat patches influences the colonization process. © 2018 by the Ecological Society of America.

Increasing Public Access to Scientific Research through Stakeholder Involvement: Ecological Effects of Sea Level Rise in the Northern Gulf of Mexico

NASA Astrophysics Data System (ADS)

Hagen, S. C.; Stephens, S. H.; DeLorme, D. E.; Ruple, D.; Graham, L.

2013-12-01

Sea level rise (SLR) has the potential to have a myriad of deleterious effects on coastal ecology and human infrastructure. Stakeholders, including managers of coastal resources, must be aware of potential consequences of SLR and adjust their plans accordingly to protect and preserve the resources under their care. Members of the public, particularly those who live or work in coastal areas, should also be informed about the results of scientific research on the effects of SLR. However, research results are frequently published in venues or formats to which resource managers and the broader public have limited access. It is imperative for scientists to move beyond traditional publication venues in order to more effectively disseminate the results of their research (Dennison, W. 2007, Estu. Coast. Shelf Sci. 77, 185). One potentially effective way to advance public access to research is to incorporate stakeholder involvement into the research project process in order to target study objectives and tailor communication products toward stakeholder needs (Lemos, M. & Morehouse, B. 2005, Glob. Env. Chg. 15, 57). However, it is important to manage communication and clarify participant expectations during this type of research (Gawith, M. et al. 2009, Glob. Env. Chg. 19, 113). This presentation describes the process being undertaken by an ongoing 5-year multi-disciplinary NOAA-funded project, Ecological Effects of Sea Level Rise in the Northern Gulf of Mexico (EESLR-NGOM), to improve accessibility and utility of scientific research results through stakeholder engagement. The EESLR-NGOM project is assessing the ecological risks from SLR along the Mississippi, Alabama and Florida Panhandle coasts, coastal habitats, and floodplains. It has incorporated stakeholder involvement throughout the research process so as to better target and tailor the emerging research products to meet resource managers' needs, as well as to facilitate eventual public dissemination of results. An

Individual dispersal delays in a cooperative breeder: Ecological constraints, the benefits of philopatry and the social queue for dominance.

PubMed

Nelson-Flower, Martha J; Wiley, Elizabeth M; Flower, Tom P; Ridley, Amanda R

2018-03-20

Delayed dispersal is a key step in the evolution of familial animal societies and cooperative breeding. However, no consensus has been reached on the ecological and social circumstances driving delayed dispersal. Here, we test predictions from the ecological constraints and benefits of philopatry hypotheses as well as the recently proposed dual benefits hypothesis to better understand the evolution of group-living and cooperative breeding. Furthermore, we consider how individual social circumstances within groups affect dispersal decisions. We examine 11 years of life-history information on a wild population of cooperatively breeding southern pied babblers Turdoides bicolor. We investigate the effects of ecological conditions, natal-group membership and individual social context on male and female dispersal delays, disperser survival and acquisition of dominance. Female dispersal decisions are generally unconstrained by ecological or social circumstances. In contrast, males disperse in response to relaxed ecological constraints, decreases in nepotistic tolerance or when low social rank in the queue for dominance decreases their likelihood of gaining a dominant breeding position. Early dispersal by end-of-queue males often leads to a head-of-queue subordinate position in a non-natal group, thereby increasing access to dominant breeding positions. However, males and females remaining in natal groups gain benefits of philopatry via increased survival and, for head-of-queue males, very high likelihood of acquisition of a breeding position. Overall, predictions from the dual benefits hypothesis best describe these results, while some predictions from each of the ecological constraints and benefits of philopatry hypotheses were supported. The benefits of living and working together (collective action benefits) in large stable groups are of central importance in shaping dispersal delays in southern pied babbler societies. In addition, position in the subordinate social

Do all frogs swim alike? The effect of ecological specialization on swimming kinematics in frogs.

PubMed

Robovska-Havelkova, Pavla; Aerts, Peter; Rocek, Zbynek; Prikryl, Tomas; Fabre, Anne-Claire; Herrel, Anthony

2014-10-15

Frog locomotion has attracted wide scientific interest because of the unusual and derived morphology of the frog pelvic girdle and hind limb. Previous authors have suggested that the design of the frog locomotor system evolved towards a specialized jumping morphology early in the radiation of the group. However, data on locomotion in frogs are biased towards a few groups and most of the ecological and functional diversity remains unexplored. Here, we examine the kinematics of swimming in eight species of frog with different ecologies. We use cineradiography to quantify movements of skeletal elements from the entire appendicular skeleton. Our results show that species with different ecologies do differ in the kinematics of swimming, with the speed of limb extension and especially the kinematics of the midfoot being different. Our results moreover suggest that this is not a phylogenetic effect because species from different clades with similar ecologies converge on the same swimming kinematics. We conclude that it is important to analyze frog locomotion in a broader ecological and evolutionary context if one is to understand the evolutionary origins of this behavior. © 2014. Published by The Company of Biologists Ltd.

Beyond positivist ecology: toward an integrated ecological ethics.

PubMed

Norton, Bryan G

2008-12-01

A post-positivist understanding of ecological science and the call for an "ecological ethic" indicate the need for a radically new approach to evaluating environmental change. The positivist view of science cannot capture the essence of environmental sciences because the recent work of "reflexive" ecological modelers shows that this requires a reconceptualization of the way in which values and ecological models interact in scientific process. Reflexive modelers are ecological modelers who believe it is appropriate for ecologists to examine the motives for their choices in developing models; this self-reflexive approach opens the door to a new way of integrating values into public discourse and to a more comprehensive approach to evaluating ecological change. This reflexive building of ecological models is introduced through the transformative simile of Aldo Leopold, which shows that learning to "think like a mountain" involves a shift in both ecological modeling and in values and responsibility. An adequate, interdisciplinary approach to ecological valuation, requires a re-framing of the evaluation questions in entirely new ways, i.e., a review of the current status of interdisciplinary value theory with respect to ecological values reveals that neither of the widely accepted theories of environmental value-neither economic utilitarianism nor intrinsic value theory (environmental ethics)-provides a foundation for an ecologically sensitive evaluation process. Thus, a new, ecologically sensitive, and more comprehensive approach to evaluating ecological change would include an examination of the metaphors that motivate the models used to describe environmental change.

Marital sex among people living with HIV receiving antiretroviral treatment in northern Thailand.

PubMed

Le Coeur, Sophie; Bozon, Michel; Lelièvre, Eva; Sirijitraporn, Preecha; Pipustanawong, Narongdate; Cowatcharagul, Worawut; Pattanapornpun, Nopporn

2014-01-01

Before the advent of effective antiretroviral treatment (ART), the sexuality of people living with HIV was mostly discussed in terms of risk. To assess the extent to which ART allows people living with HIV to regain a regular sexual life, we surveyed all HIV-infected people treated in four hospitals in Northern Thailand and a control group from the general population matched by sex, age and residence. Data included socio-demographic and health characteristics, frequency of sexual intercourse in the last month and condom use. Our findings indicate that people living with HIV less often live in steady partnership (50% of the HIV-infected people versus 79% of the controls). After adjusting for factors known to influence sexuality, their probability of being sexually active was estimated to be about half that of the controls. When sexually active, men had a reduced sexual activity compared to controls (2.8 intercourse in the last month versus 4.0), while levels of reported sexual activity were similar among women (2.2 versus 2.8, respectively). Consistent condom use was high among people living with HIV (66% for women and 70% for men).

Half-time strategies to enhance second-half performance in team-sports players: a review and recommendations.

PubMed

Russell, Mark; West, Daniel J; Harper, Liam D; Cook, Christian J; Kilduff, Liam P

2015-03-01

A number of intermittent team sports require that two consecutive periods of play (lasting for ~30-45 min) are separated by a 10-20 min half-time break. The half-time practices employed by team-sports players generally include returning to the changing rooms, temporarily relaxing from the cognitive and physical demands of the first half, rehydration and re-fuelling strategies, addressing injury or equipment concerns, and receiving tactical instruction and coach feedback. However, the typically passive nature of these actions has been associated with physiological changes that impair performance during the second half. Both physical and cognitive performances have been found to decline in the initial stages of subsequent exercise that follows half-time. An increased risk of injury has also been observed during this period. Therefore, half-time provides sports scientists and strength and conditioning coaches with an opportunity to optimise second-half performance. An overview of strategies thought to benefit team-sports athletes is presented; specifically, the efficacy of heat maintenance strategies (including passive and active methods), post-activation potentiation, hormonal priming, and modified hydro-nutritional practices are discussed. A theoretical model of applying these strategies in a manner that compliments current practice is also offered.

Planning of Green Space Ecological Network in Urban Areas: An Example of Nanchang, China

PubMed Central

Li, Haifeng; Chen, Wenbo; He, Wei

2015-01-01

Green space plays an important role in sustainable urban development and ecology by virtue of multiple environmental, recreational, and economic benefits. Constructing an effective and harmonious urban ecological network and maintaining a sustainable living environment in response to rapid urbanization are the key issues required to be resolved by landscape planners. In this paper, Nanchang City, China was selected as a study area. Based on a series of landscape metrics, the landscape pattern analysis of the current (in 2005) and planned (in 2020) green space system were, respectively, conducted by using FRAGSTATS 3.3 software. Considering the actual situation of the Nanchang urban area, a “one river and two banks, north and south twin cities” ecological network was constructed by using network analysis. Moreover, the ecological network was assessed by using corridor structure analysis, and the improvement of an ecological network on the urban landscape was quantitatively assessed through a comparison between the ecological network and green space system planning. The results indicated that: (1) compared to the green space system in 2005, the planned green space system in 2020 of the Nanchang urban area will decline in both districts (Changnan and Changbei districts). Meanwhile, an increase in patch density and a decrease in mean patch size of green space patches at the landscape level implies the fragmentation of the urban green space landscape. In other words, the planned green space system does not necessarily improve the present green space system; (2) the ecological network of two districts has high corridor density, while Changnan’s ecological network has higher connectivity, but Changbei’s ecological network is more viable from an economic point of view, since it has relatively higher cost efficiency; (3) decrease in patch density, Euclidean nearest neighbor distance, and an increase in mean patch size and connectivity implied that the ecological

Planning of Green Space Ecological Network in Urban Areas: An Example of Nanchang, China.

PubMed

Li, Haifeng; Chen, Wenbo; He, Wei

2015-10-15

Green space plays an important role in sustainable urban development and ecology by virtue of multiple environmental, recreational, and economic benefits. Constructing an effective and harmonious urban ecological network and maintaining a sustainable living environment in response to rapid urbanization are the key issues required to be resolved by landscape planners. In this paper, Nanchang City, China was selected as a study area. Based on a series of landscape metrics, the landscape pattern analysis of the current (in 2005) and planned (in 2020) green space system were, respectively, conducted by using FRAGSTATS 3.3 software. Considering the actual situation of the Nanchang urban area, a "one river and two banks, north and south twin cities" ecological network was constructed by using network analysis. Moreover, the ecological network was assessed by using corridor structure analysis, and the improvement of an ecological network on the urban landscape was quantitatively assessed through a comparison between the ecological network and green space system planning. The results indicated that: (1) compared to the green space system in 2005, the planned green space system in 2020 of the Nanchang urban area will decline in both districts (Changnan and Changbei districts). Meanwhile, an increase in patch density and a decrease in mean patch size of green space patches at the landscape level implies the fragmentation of the urban green space landscape. In other words, the planned green space system does not necessarily improve the present green space system; (2) the ecological network of two districts has high corridor density, while Changnan's ecological network has higher connectivity, but Changbei's ecological network is more viable from an economic point of view, since it has relatively higher cost efficiency; (3) decrease in patch density, Euclidean nearest neighbor distance, and an increase in mean patch size and connectivity implied that the ecological network

Living with the Heat. Submarine Ring of Fire--Grades 5-6. Hydrothermal Vent Ecology.

ERIC Educational Resources Information Center

National Oceanic and Atmospheric Administration (DOC), Rockville, MD.

This activity is designed to teach about hydrothermal vent ecology. Students are expected to describe how hydrothermal vents are formed and characterize the physical conditions at these sites, explain chemosynthesis and contrast this process with photosynthesis, identify autotrophic bacteria as the basis for food webs in hydrothermal vent…

[Regional ecological construction and mission of landscape ecology].

PubMed

Xiao, Duning; Xie, Fuju; Wei, Jianbing

2004-10-01

The eco-construction on regional and landscape scale is the one which can be used to specific landscape and intercrossing ecosystem in specific region including performing scientific administration of ecosystem and optimizing environmental function. Recently, the government has taken a series of significant projects into action, such as national forest protection item, partly forest restoration, and adjustment of water, etc. Enforcing regional eco-construction and maintaining the ecology security of the nation have become the strategic requisition. In various regions, different eco-construction should be applied, for example, performing ecological safeguard measure in ecological sensitive zone, accommodating the ecological load in ecological fragile zone, etc., which can control the activities of human being, so that, sustainable development can be reached. Facing opportunity and challenge in the development of landscape ecology, we have some key topics: landscape pattern of ecological security, land use and ecological process, landscape changes under human activity stress, quantitative evaluation of the influence on human being activities, evaluation of zonal ecological security and advance warning of ecological risk, and planning and optimizing of model in landscape eco-construction.

Silviculture-ecology of forest-zone hardwoods in the Sierra Nevada

Treesearch

Philip M. McDonald; John C. Tappeiner

1996-01-01

Although the principal hardwood species in the forest zone of the Sierra Nevada (California black oak, tanoak, Pacific madrone, and canyon live oak) are key components of many ecosystems, they have received comparatively little study. Currently they are underutilized and unmanaged. This paper brings together what is known on the silviculture-ecology of these species...

Synchronous Half-Wave Rectifier

NASA Technical Reports Server (NTRS)

Rippel, Wally E.

1989-01-01

Synchronous rectifying circuit behaves like diode having unusually low voltage drop during forward-voltage half cycles. Circuit particularly useful in power supplies with potentials of 5 Vdc or less, where normal forward-voltage drops in ordinary diodes unacceptably large. Fabricated as monolithic assembly or as hybrid. Synchronous half-wave rectifier includes active circuits to attain low forward voltage drop and high rectification efficiency.

Assessing the Effectiveness of a Computer Simulation for Teaching Ecological Experimental Design

ERIC Educational Resources Information Center

Stafford, Richard; Goodenough, Anne E.; Davies, Mark S.

2010-01-01

Designing manipulative ecological experiments is a complex and time-consuming process that is problematic to teach in traditional undergraduate classes. This study investigates the effectiveness of using a computer simulation--the Virtual Rocky Shore (VRS)--to facilitate rapid, student-centred learning of experimental design. We gave a series of…

Family Wellness: An Ecological Perspective.

ERIC Educational Resources Information Center

Fannin, Ronald A.

Bronfenbrenner's (1979) concept of human ecology emphasizes the effect of the environment, both physical and psychological, on individual development. Bronfenbrenner's contexts which affect the development of the individual (microsystem, mesosystem, exosystem, macrosystem) can also be defined for the family in an ecological model of family…

The Second Skin: Ecological Role of Epibiotic Biofilms on Marine Organisms

PubMed Central

Wahl, Martin; Goecke, Franz; Labes, Antje; Dobretsov, Sergey; Weinberger, Florian

2012-01-01

In the aquatic environment, biofilms on solid surfaces are omnipresent. The outer body surface of marine organisms often represents a highly active interface between host and biofilm. Since biofilms on living surfaces have the capacity to affect the fluxes of information, energy, and matter across the host’s body surface, they have an important ecological potential to modulate the abiotic and biotic interactions of the host. Here we review existing evidence how marine epibiotic biofilms affect their hosts’ ecology by altering the properties of and processes across its outer surfaces. Biofilms have a huge potential to reduce its host’s access to light, gases, and/or nutrients and modulate the host’s interaction with further foulers, consumers, or pathogens. These effects of epibiotic biofilms may intensely interact with environmental conditions. The quality of a biofilm’s impact on the host may vary from detrimental to beneficial according to the identity of the epibiotic partners, the type of interaction considered, and prevailing environmental conditions. The review concludes with some unresolved but important questions and future perspectives. PMID:22936927

Assessing the potential for using wetlands as intermediary storages to conjunctively maintain ecological values and support agricultural demands.

PubMed

Ning, Nathan S P; Watkins, Susanne C; Gawne, Ben; Nielsen, Daryl L

2012-09-30

Water sharing to meet both agricultural and environmental demands is a critical issue affecting the health of many floodplain river systems around the world. This study explored the potential for using wetlands as temporary off-river storages to conjunctively maintain ecological values and support agricultural demands by assessing the effects of artificial drawdown on wetland aquatic plant communities. An initial experiment was undertaken in outdoor mesocosms in which four different treatments were compared over a 131 day duration: (1) natural drawdown where the water was left to drawdown naturally via evaporation; (2) partial drawdown where approximately half of the volume of water was pumped out after 42 days; (3) stepped drawdown where approximately half of the volume of water pumped out after 42 days, and then the remaining volume of water was pumped out after 117 days; and (4) total drawdown where all of the of water was pumped out after 117 days. A complementary field study was subsequently undertaken where two wetlands were left to drawdown naturally and two were partially drawn down artificially (i.e. had approximately half of their volume removed by pumping). Results from both of these studies indicated that neither aquatic plant abundance nor taxon richness were adversely affected by partial drawdown. Rather, both studies showed that aquatic plant communities subjected to a partial drawdown treatment became more species rich and diverse than communities subjected to a natural drawdown treatment. This suggests that it may be possible to use wetlands as intermediary storages for the dual purposes of maintaining ecological values and supporting agricultural demands. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

Effects of strain on the half-metallicity and spin gapless feature of Ti2YSi (Y = Fe, Co) alloys

NASA Astrophysics Data System (ADS)

Fan, Xiaoguang; Li, Jincheng; Jin, Yingjiu

2018-05-01

Half-metals and spin gapless semiconductors (SGSs), which exhibit 100% spin polarization at the Fermi level, are considered important candidates for spintronics. Using first-principles calculations, we have investigated the effects of uniform strain and tetragonal distortion on the half-metallicity and spin gapless feature of inverse Heusler Ti2YSi (Y = Fe and Co) alloys. Results show that for uniform strains, the half-metallicity occurs in the ranges of lattice parameters from 5.938 Å to 6.535 Å for Ti2FeSi and from 5.924 Å to 6.840 Å for Ti2CoSi. Tetragonal distortions over the ranges of ‑2.0% to +2.5% and ‑2.6% to +4.1% could destroy the half-metallicity for Ti2FeSi and Ti2CoSi, respectively. On the other hand, Ti2CoSi is an SGS at lattice constants of 5.968-6.023 Å. An interesting finding is that Ti2CoSi reproduces the SGS character with increasing the lattice parameters to 6.784-6.840 Å. Small tetragonal distortions with ±0.2% will destroy the SGS character of Ti2CoSi.

Author contributions to ecological publications: What does it mean to be an author in modern ecological research?

PubMed Central

Logan, John M.; Bean, Sarah B.; Myers, Andrew E.

2017-01-01

Authorship is a central element of scientific research carrying a variety of rewards and responsibilities, and while various guidelines exist, actual author contributions are often ambiguous. Inconsistent or limited contributions threaten to devalue authorship as intellectual currency and diminish authors’ responsibility for published content. Researchers have assessed author contributions in the medical literature and other research fields, but similar data for the field of ecological research are lacking. Authorship practices in ecological research are broadly representative of a variety of fields due to the cross-disciplinary nature of collaborations in ecological studies. To better understand author contributions to current research, we distributed a survey regarding co-author contributions to a random selection of 996 lead authors of manuscripts published in ecological journals in 2010. We obtained useable responses from 45% of surveyed authors. Reported lead author contributions in ecological research studies consistently included conception of the project idea, data collection, analysis, and writing. Middle and last author contributions instead showed a high level of individual variability. Lead authorship in ecology is well defined while secondary authorship is more ambiguous. Nearly half (48%) of all studies included in our survey had some level of non-compliance with Ecological Society of America (ESA) authorship guidelines and the majority of studies (78%) contained at least one co-author that did not meet International Committee of Medical Journal Editors (ICMJE) requirements. Incidence of non-compliance varied with lead author occupation and author position. The probability of a study including an author that was non-compliant with ESA guidelines was lowest for professor-led studies and highest for graduate student and post doctoral researcher-led studies. Among studies with > two co-authors, all lead authors met ESA guidelines and only 2% failed to

Author contributions to ecological publications: What does it mean to be an author in modern ecological research?

PubMed

Logan, John M; Bean, Sarah B; Myers, Andrew E

2017-01-01

Authorship is a central element of scientific research carrying a variety of rewards and responsibilities, and while various guidelines exist, actual author contributions are often ambiguous. Inconsistent or limited contributions threaten to devalue authorship as intellectual currency and diminish authors' responsibility for published content. Researchers have assessed author contributions in the medical literature and other research fields, but similar data for the field of ecological research are lacking. Authorship practices in ecological research are broadly representative of a variety of fields due to the cross-disciplinary nature of collaborations in ecological studies. To better understand author contributions to current research, we distributed a survey regarding co-author contributions to a random selection of 996 lead authors of manuscripts published in ecological journals in 2010. We obtained useable responses from 45% of surveyed authors. Reported lead author contributions in ecological research studies consistently included conception of the project idea, data collection, analysis, and writing. Middle and last author contributions instead showed a high level of individual variability. Lead authorship in ecology is well defined while secondary authorship is more ambiguous. Nearly half (48%) of all studies included in our survey had some level of non-compliance with Ecological Society of America (ESA) authorship guidelines and the majority of studies (78%) contained at least one co-author that did not meet International Committee of Medical Journal Editors (ICMJE) requirements. Incidence of non-compliance varied with lead author occupation and author position. The probability of a study including an author that was non-compliant with ESA guidelines was lowest for professor-led studies and highest for graduate student and post doctoral researcher-led studies. Among studies with > two co-authors, all lead authors met ESA guidelines and only 2% failed to

The raison d'être of chemical ecology.

PubMed

Raguso, Robert A; Agrawal, Anurag A; Douglas, Angela E; Jander, Georg; Kessler, André; Poveda, Katja; Thaler, Jennifer S

2015-03-01

Chemical ecology is a mechanistic approach to understanding the causes and consequences of species interactions, distribution, abundance, and diversity. The promise of chemical ecology stems from its potential to provide causal mechanisms that further our understanding of ecological interactions and allow us to more effectively manipulate managed systems. Founded on the notion that all organisms use endogenous hormones and chemical compounds that mediate interactions, chemical ecology has flourished over the past 50 years since its origin. In this essay we highlight the breadth of chemical ecology, from its historical focus on pheromonal communication, plant-insect interactions, and coevolution to frontier themes including community and ecosystem effects of chemically mediated species interactions. Emerging approaches including the -omics, phylogenetic ecology, the form and function of microbiomes, and network analysis, as well as emerging challenges (e.g., sustainable agriculture and public health) are guiding current growth of this field. Nonetheless, the directions and approaches we advocate for the future are grounded in classic ecological theories and hypotheses that continue to motivate our broader discipline.

Landscape Sources, Ecological Effects, and Management of Nutrients in Lakes of Northeastern USA

EPA Science Inventory

Lakes face escalating pressures associated with land cover change and growing human populations. Ecological responses provide context for identifying stressor severity, land use impacts, and management effectiveness. We used EPA National Lakes Assessment data and GIS to develop i...

Effective Half-Life of Caesium-137 in Various Environmental Media at the Savannah River Site

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

Paller, M. H.; Jannik, G. T.; Baker, R. A.

2014-05-01

During the operational history of the Savannah River Site (SRS), many different radionuclides have been released from site facilities into the SRS environment. However, only a relatively small number of pathways, most importantly 137Cs in fish and deer, have contributed significantly to doses and risks to the public. The “effective” half-lives (T e) of 137Cs (which include both physical decay and environmental dispersion) in Savannah River floodplain soil and vegetation and in fish and white-tailed deer from the SRS were estimated using long-term monitoring data. For 1974–2011, the T es of 137Cs in Savannah River floodplain soil and vegetation weremore » 17.0 years (95% CI = 14.2–19.9) and 13.4 years (95% CI = 10.8–16.0), respectively. These T es were greater than in a previous study that used data collected only through 2005 as a likely result of changes in the flood regime of the Savannah River. Field analyses of 137Cs concentrations in deer collected during yearly controlled hunts at the SRS indicated an overall T e of 15.9 years (95% CI = 12.3–19.6) for 1965–2011; however, the T e for 1990–2011 was significantly shorter (11.8 years, 95% CI = 4.8–18.8) due to an increase in the rate of 137Cs removal. The shortest T es were for fish in SRS streams and the Savannah River (3.5–9.0 years), where dilution and dispersal resulted in rapid 137Cs removal. Long-term data show that T es are significantly shorter than the physical half-life of 137Cs in the SRS environment but that they can change over time. Therefore, it is desirable have a long period of record for calculating Tes and risky to extrapolate T es beyond this period unless the processes governing 137Cs removal are clearly understood.« less

Refined boundary conditions on the free surface of an elastic half-space taking into account non-local effects.

PubMed

Chebakov, R; Kaplunov, J; Rogerson, G A

2016-02-01

The dynamic response of a homogeneous half-space, with a traction-free surface, is considered within the framework of non-local elasticity. The focus is on the dominant effect of the boundary layer on overall behaviour. A typical wavelength is assumed to considerably exceed the associated internal lengthscale. The leading-order long-wave approximation is shown to coincide formally with the 'local' problem for a half-space with a vertical inhomogeneity localized near the surface. Subsequent asymptotic analysis of the inhomogeneity results in an explicit correction to the classical boundary conditions on the surface. The order of the correction is greater than the order of the better-known correction to the governing differential equations. The refined boundary conditions enable us to evaluate the interior solution outside a narrow boundary layer localized near the surface. As an illustration, the effect of non-local elastic phenomena on the Rayleigh wave speed is investigated.

Socio-ecological Influences on Health-Care Access and Navigation Among Persons of Mexican Descent Living on the U.S./Mexico Border

PubMed Central

Barroso, Cristina S.; Mitchell-Bennett, Lisa; Chavez, Marge; Fernandez, Maria E.; Cantu, Ethel; Smith, Kirk L.; Fisher-Hoch, Susan P.

2013-01-01

The study reported here examines factors influencing decision-making concerning health care access and navigation among persons of Mexican origin living along the U.S./Mexico border. Specifically, the study examined how persons with limited financial resources accessed these two systems. Seven focus groups were held with 52 low income Mexican American people aged 18–65 years. Transcripts were analyzed to identify themes in Atlasti 5.0 software and the theory used included a socio-ecological framework and complemented by constructed from the Social Cognitive Theory. We found that in addition to a lack of insurance and financial resources to pay for health care; fear, embarrassment and denial associated with a diagnosis of illness; poor medical personnel interactions, and desire for quality but streamlined health care also influenced decision making. This theory-based study raises important issues if health care is to improve the health and welfare of disadvantaged populations and points to the need for greater focus on medical homes and prevention and early intervention approaches. PMID:23011576

Hair-to-blood ratio and biological half-life of mercury: experimental study of methylmercury exposure through fish consumption in humans.

PubMed

Yaginuma-Sakurai, Kozue; Murata, Katsuyuki; Iwai-Shimada, Miyuki; Nakai, Kunihiko; Kurokawa, Naoyuki; Tatsuta, Nozomi; Satoh, Hiroshi

2012-02-01

The hair-to-blood ratio and biological half-life of methylmercury in a one-compartment model seem to differ between past and recent studies. To reevaluate them, 27 healthy volunteers were exposed to methylmercury at the provisional tolerable weekly intake (3.4 µg/kg body weight/week) for adults through fish consumption for 14 weeks, followed by a 15-week washout period after the cessation of exposure. Blood was collected every 1 or 2 weeks, and hair was cut every 4 weeks. Total mercury (T-Hg) concentrations were analyzed in blood and hair. The T-Hg levels of blood and hair changed with time (p < 0.001). The mean concentrations increased from 6.7 ng/g at week 0 to 26.9 ng/g at week 14 in blood, and from 2.3 to 8.8 µg/g in hair. The mean hair-to-blood ratio after the adjustment for the time lag from blood to hair was 344 ± 54 (S.D.) for the entire period. The half-lives of T-Hg were calculated from raw data to be 94 ± 23 days for blood and 102 ± 31 days for hair, but the half-lives recalculated after subtracting the background levels from the raw data were 57 ± 18 and 64 ± 22 days, respectively. In conclusion, the hair-to-blood ratio of methylmercury, based on past studies, appears to be underestimated in light of recent studies. The crude half-life may be preferred rather than the recalculated one because of the practicability and uncertainties of the background level, though the latter half-life may approximate the conventional one.

Functional Group, Biomass, and Climate Change Effects on Ecological Drought in Semiarid Grasslands

NASA Astrophysics Data System (ADS)

Wilson, S. D.; Schlaepfer, D. R.; Bradford, J. B.; Lauenroth, W. K.; Duniway, M. C.; Hall, S. A.; Jamiyansharav, K.; Jia, G.; Lkhagva, A.; Munson, S. M.; Pyke, D. A.; Tietjen, B.

2018-03-01

Water relations in plant communities are influenced both by contrasting functional groups (grasses and shrubs) and by climate change via complex effects on interception, uptake, and transpiration. We modeled the effects of functional group replacement and biomass increase, both of which can be outcomes of invasion and vegetation management, and climate change on ecological drought (soil water potential below which photosynthesis stops) in 340 semiarid grassland sites over 30 year periods. Relative to control vegetation (climate and site-determined mixes of functional groups), the frequency and duration of drought were increased by shrubs and decreased by annual grasses. The rankings of shrubs, control vegetation, and annual grasses in terms of drought effects were generally consistent in current and future climates, suggesting that current differences among functional groups on drought effects predict future differences. Climate change accompanied by experimentally increased biomass (i.e., the effects of invasions that increase community biomass or management that increases productivity through fertilization or respite from grazing) increased drought frequency and duration and advanced drought onset. Our results suggest that the replacement of perennial temperate semiarid grasslands by shrubs, or increased biomass, can increase ecological drought in both current and future climates.

Functional group, biomass, and climate change effects on ecological drought in semiarid grasslands

USGS Publications Warehouse

Wilson, Scott D.; Schlaepfer, Daniel R.; Bradford, John B.; Lauenroth, William K.; Duniway, Michael C.; Hall, Sonia A.; Jamiyansharav, Khishigbayar; Jia, Gensuo; Lkhagva, Ariuntsetseg; Munson, Seth M.; Pyke, David A.; Tietjen, Britta

2018-01-01

Water relations in plant communities are influenced both by contrasting functional groups (grasses, shrubs) and by climate change via complex effects on interception, uptake and transpiration. We modelled the effects of functional group replacement and biomass increase, both of which can be outcomes of invasion and vegetation management, and climate change on ecological drought (soil water potential below which photosynthesis stops) in 340 semiarid grassland sites over 30‐year periods. Relative to control vegetation (climate and site‐determined mixes of functional groups), the frequency and duration of drought were increased by shrubs and decreased by annual grasses. The rankings of shrubs, control vegetation, and annual grasses in terms of drought effects were generally consistent in current and future climates, suggesting that current differences among functional groups on drought effects predict future differences. Climate change accompanied by experimentally‐increased biomass (i.e. the effects of invasions that increase community biomass, or management that increases productivity through fertilization or respite from grazing) increased drought frequency and duration, and advanced drought onset. Our results suggest that the replacement of perennial temperate semiarid grasslands by shrubs, or increased biomass, can increase ecological drought both in current and future climates.

Ecological Determinants of Highly Pathogenic Avian Influenza (H5N1) Outbreaks in Bangladesh

PubMed Central