Social support and social undermining as explanatory factors for health-related quality of life in people living with HIV/AIDS.

PubMed

Oetzel, John; Wilcox, Bryan; Archiopoli, Ashley; Avila, Magdalena; Hell, Cia; Hill, Ricky; Muhammad, Michael

2014-01-01

This study aimed to examine the influence of social support (from personal networks and health care providers) and social undermining (from personal networks) on health-related quality of life (HRQOL; general health perceptions, physical functioning, and depression). Specifically, the authors aimed to identify the nature of the effects (direct, mediating, or moderating) of social support and social undermining on HRQOL. A total of 344 people living with HIV/AIDS and who were patients in a federally funded clinic in New Mexico completed a self-report survey questionnaire. The major findings of this study are the following: (a) social support and social undermining had direct and indirect effects on HRQOL-there was no evidence of a moderating effect of social support and social undermining; (b) for direct effects, social undermining was a stronger predictor of HRQOL than social support with social support variables having positive relations and social undermining variables having negative relations with HRQOL; and (c) for indirect effects, providers' social support partially mediated the influence of unstable employment/unemployment and social undermining on HRQOL.

Co-occurrence Patterns of the Dengue Vector Aedes aegypti and Aedes mediovitattus, a Dengue Competent Mosquito in Puerto Rico

PubMed Central

Little, Eliza; Barrera, Roberto; Seto, Karen C.; Diuk-Wasser, Maria

2015-01-01

Aedes aegypti is implicated in dengue transmission in tropical and subtropical urban areas around the world. Ae. aegypti populations are controlled through integrative vector management. However, the efficacy of vector control may be undermined by the presence of alternative, competent species. In Puerto Rico, a native mosquito, Ae. mediovittatus, is a competent dengue vector in laboratory settings and spatially overlaps with Ae. aegypti. It has been proposed that Ae. mediovittatus may act as a dengue reservoir during inter-epidemic periods, perpetuating endemic dengue transmission in rural Puerto Rico. Dengue transmission dynamics may therefore be influenced by the spatial overlap of Ae. mediovittatus, Ae. aegypti, dengue viruses, and humans. We take a landscape epidemiology approach to examine the association between landscape composition and configuration and the distribution of each of these Aedes species and their co-occurrence. We used remotely sensed imagery from a newly launched satellite to map landscape features at very high spatial resolution. We found that the distribution of Ae. aegypti is positively predicted by urban density and by the number of tree patches, Ae. mediovittatus is positively predicted by the number of tree patches, but negatively predicted by large contiguous urban areas, and both species are predicted by urban density and the number of tree patches. This analysis provides evidence that landscape composition and configuration is a surrogate for mosquito community composition, and suggests that mapping landscape structure can be used to inform vector control efforts as well as to inform urban planning. PMID:21989642

Spatial self-organization favors heterotypic cooperation over cheating.

PubMed

Momeni, Babak; Waite, Adam James; Shou, Wenying

2013-11-12

Heterotypic cooperation-two populations exchanging distinct benefits that are costly to produce-is widespread. Cheaters, exploiting benefits while evading contribution, can undermine cooperation. Two mechanisms can stabilize heterotypic cooperation. In 'partner choice', cooperators recognize and choose cooperating over cheating partners; in 'partner fidelity feedback', fitness-feedback from repeated interactions ensures that aiding your partner helps yourself. How might a spatial environment, which facilitates repeated interactions, promote fitness-feedback? We examined this process through mathematical models and engineered Saccharomyces cerevisiae strains incapable of recognition. Here, cooperators and their heterotypic cooperative partners (partners) exchanged distinct essential metabolites. Cheaters exploited partner-produced metabolites without reciprocating, and were competitively superior to cooperators. Despite initially random spatial distributions, cooperators gained more partner neighbors than cheaters did. The less a cheater contributed, the more it was excluded and disfavored. This self-organization, driven by asymmetric fitness effects of cooperators and cheaters on partners during cell growth into open space, achieves assortment. DOI: http://dx.doi.org/10.7554/eLife.00960.001.

Spatial self-organization favors heterotypic cooperation over cheating

PubMed Central

Momeni, Babak; Waite, Adam James; Shou, Wenying

2013-01-01

Heterotypic cooperation—two populations exchanging distinct benefits that are costly to produce—is widespread. Cheaters, exploiting benefits while evading contribution, can undermine cooperation. Two mechanisms can stabilize heterotypic cooperation. In ‘partner choice’, cooperators recognize and choose cooperating over cheating partners; in ‘partner fidelity feedback’, fitness-feedback from repeated interactions ensures that aiding your partner helps yourself. How might a spatial environment, which facilitates repeated interactions, promote fitness-feedback? We examined this process through mathematical models and engineered Saccharomyces cerevisiae strains incapable of recognition. Here, cooperators and their heterotypic cooperative partners (partners) exchanged distinct essential metabolites. Cheaters exploited partner-produced metabolites without reciprocating, and were competitively superior to cooperators. Despite initially random spatial distributions, cooperators gained more partner neighbors than cheaters did. The less a cheater contributed, the more it was excluded and disfavored. This self-organization, driven by asymmetric fitness effects of cooperators and cheaters on partners during cell growth into open space, achieves assortment. DOI: http://dx.doi.org/10.7554/eLife.00960.001 PMID:24220506

Neural basis of the undermining effect of monetary reward on intrinsic motivation

PubMed Central

Murayama, Kou; Matsumoto, Madoka; Izuma, Keise; Matsumoto, Kenji

2010-01-01

Contrary to the widespread belief that people are positively motivated by reward incentives, some studies have shown that performance-based extrinsic reward can actually undermine a person's intrinsic motivation to engage in a task. This “undermining effect” has timely practical implications, given the burgeoning of performance-based incentive systems in contemporary society. It also presents a theoretical challenge for economic and reinforcement learning theories, which tend to assume that monetary incentives monotonically increase motivation. Despite the practical and theoretical importance of this provocative phenomenon, however, little is known about its neural basis. Herein we induced the behavioral undermining effect using a newly developed task, and we tracked its neural correlates using functional MRI. Our results show that performance-based monetary reward indeed undermines intrinsic motivation, as assessed by the number of voluntary engagements in the task. We found that activity in the anterior striatum and the prefrontal areas decreased along with this behavioral undermining effect. These findings suggest that the corticobasal ganglia valuation system underlies the undermining effect through the integration of extrinsic reward value and intrinsic task value. PMID:21078974

Neural basis of the undermining effect of monetary reward on intrinsic motivation.

PubMed

Murayama, Kou; Matsumoto, Madoka; Izuma, Keise; Matsumoto, Kenji

2010-12-07

Contrary to the widespread belief that people are positively motivated by reward incentives, some studies have shown that performance-based extrinsic reward can actually undermine a person's intrinsic motivation to engage in a task. This "undermining effect" has timely practical implications, given the burgeoning of performance-based incentive systems in contemporary society. It also presents a theoretical challenge for economic and reinforcement learning theories, which tend to assume that monetary incentives monotonically increase motivation. Despite the practical and theoretical importance of this provocative phenomenon, however, little is known about its neural basis. Herein we induced the behavioral undermining effect using a newly developed task, and we tracked its neural correlates using functional MRI. Our results show that performance-based monetary reward indeed undermines intrinsic motivation, as assessed by the number of voluntary engagements in the task. We found that activity in the anterior striatum and the prefrontal areas decreased along with this behavioral undermining effect. These findings suggest that the corticobasal ganglia valuation system underlies the undermining effect through the integration of extrinsic reward value and intrinsic task value.

The Mediating Role of Autonomy and Relatedness on Maternal and Child Outcomes.

PubMed

Guo, Xiamei; Slesnick, Natasha

2018-02-01

The current study examined the mediating role of both mother and child interactive behaviors, which granted or undermined autonomy and relatedness, on the bidirectional and longitudinal association between maternal depressive symptoms and child internalizing behaviors, as well as the association between maternal substance use and child externalizing behaviors. Child's sex and mother's drug of choice were explored as potential moderators of the mediation relationship. Data were collected from 183 dyads including treatment-seeking substance using mothers and their children (95 males, aged between 8 and 16 years old). Structural equation modeling analysis showed girls' internalizing and externalizing behaviors at the 3-month follow-up were negatively associated with the same behaviors at the 12-month follow-up through increased relatedness undermining behaviors from their mothers at the 6-month follow-up. Among mothers with opioids as their drug of choice (DOC), children's externalizing behaviors at the 3-month follow-up were positively associated with mothers' substance use at the 12-month follow-up through the elevated levels of mothers' relatedness undermining behaviors at the 6-month follow-up. Among mothers with alcohol as their DOC, maternal depressive symptoms at the 3-month follow-up were positively related to children's internalizing behaviors at the 12-month follow-up through reduced relatedness undermining behaviors exhibited by mothers at the 6-month follow-up. To our knowledge, this is one of the first studies to attempt to unravel these longitudinal and bidirectional influences as well as the moderated mediation pathways among families with a substance using mothers.

Undermining Critical Consciousness Unconsciously: Restoring Hope in the Multicultural Education Idea

ERIC Educational Resources Information Center

Gatimu, M. Wangeci

2009-01-01

The main goal of multicultural education is to transform the structural factors in the educational system in order to redress inequalities and inequities for historically underprivileged populations (Banks "1997"). This article addresses theories and practices that frame multicultural education in teaching and learning contexts. How do teachers…

Splicing Ourselves into the Machine: Electronic Communities, Systems Theory, and Composition Studies.

ERIC Educational Resources Information Center

LaGrandeur, Kevin

Computer mediated communication (CMC) tends to erase power structures because such communication somehow undermines or escapes discursive limits. Online discussions seem to promote rhetorical experimentation on the part of the participants. Finding a way to explain disparities between electronic discussion and oral discussion has proven difficult.…

Sidewalk undermining studies : phase III, field and model studies.

DOT National Transportation Integrated Search

1979-01-01

The results of the early studies of the undermining problems are summarized in the initial portion of this report. Additionally, the design and use of a model sidewalk for testing procedures for preventing undermining are described. Based upon tests ...

Sidewalk undermining studies : phase I, hydrology and maintenance studies.

DOT National Transportation Integrated Search

1975-01-01

Studies of the maintenance and hydrology considerations involved in a sidewalk undermining problem in the Fairfax area are reported. Sidewalk undermining is attributed principally to a highly erodible soil found in much of the area and to the fact th...

An indicative method for determination of the most hazardous changes in slopes of the subsidence basins in underground coal mining area in Ostrava (Czech Republic).

PubMed

Marschalko, Marian; Yilmaz, Isik; Křístková, Veronika; Fuka, Matěj; Kubečka, Karel; Bouchal, Tomáš

2013-01-01

Considering growing population and decreasing mineral resource reserves, the issue of undermining has been and shall remain very topical. This study aims to identify the mutual connections between mined out panels of a deposit and the final manifestations on the ground surface related to deep black coal mining. On the grounds of the identified connections, the study describes a method to simplify a common evaluation of undermined areas according to building site categories. Within the study, a demarcation of the areas was conducted in two localities in Czech Republic influenced by the effects of undermining in the Upper-Silesian Basin. In the allotment of the CSM Mine, an area unsuitable for founding structures was defined from the centre of the worked out workings to the distance of 175 m from the panel's edge, for which the corresponding break angle is 78.3°. Similarly, in the allotment of the Paskov Mine, an area unsuitable for founding structures was determined to the distance of 500 m from the panel's edge, for which the corresponding break angle is 50.2°. This demarcation may be implemented prior to deposit mining being aware of several physical-mechanical parameters of rocks in the deposit's overburden. Having mined out a particular section of a deposit, it is recommended to verify the values of break angle using the method described herein. The study may be applied as a relatively fast and effective method to evaluate future land use for planning.

Correction of Spatial Bias in Oligonucleotide Array Data

PubMed Central

Lemieux, Sébastien

2013-01-01

Background. Oligonucleotide microarrays allow for high-throughput gene expression profiling assays. The technology relies on the fundamental assumption that observed hybridization signal intensities (HSIs) for each intended target, on average, correlate with their target's true concentration in the sample. However, systematic, nonbiological variation from several sources undermines this hypothesis. Background hybridization signal has been previously identified as one such important source, one manifestation of which appears in the form of spatial autocorrelation. Results. We propose an algorithm, pyn, for the elimination of spatial autocorrelation in HSIs, exploiting the duality of desirable mutual information shared by probes in a common probe set and undesirable mutual information shared by spatially proximate probes. We show that this correction procedure reduces spatial autocorrelation in HSIs; increases HSI reproducibility across replicate arrays; increases differentially expressed gene detection power; and performs better than previously published methods. Conclusions. The proposed algorithm increases both precision and accuracy, while requiring virtually no changes to users' current analysis pipelines: the correction consists merely of a transformation of raw HSIs (e.g., CEL files for Affymetrix arrays). A free, open-source implementation is provided as an R package, compatible with standard Bioconductor tools. The approach may also be tailored to other platform types and other sources of bias. PMID:23573083

Using spatialized sound cues in an auditorily rich environment

NASA Astrophysics Data System (ADS)

Brock, Derek; Ballas, James A.; Stroup, Janet L.; McClimens, Brian

2004-05-01

Previous Navy research has demonstrated that spatialized sound cues in an otherwise quiet setting are useful for directing attention and improving performance by 16.8% or more in the decision component of a complex dual-task. To examine whether the benefits of this technique are undermined in the presence of additional, unrelated sounds, a background recording of operations in a Navy command center and a voice communications response task [Bolia et al., J. Acoust. Soc. Am. 107, 1065-1066 (2000)] were used to simulate the conditions of an auditorily rich military environment. Without the benefit of spatialized sound cues, performance in the presence of this extraneous auditory information, as measured by decision response times, was an average of 13.6% worse than baseline performance in an earlier study. Performance improved when the cues were present by an average of 18.3%, but this improvement remained below the improvement observed in the baseline study by an average of 11.5%. It is concluded that while the two types of extraneous sound information used in this study degrade performance in the decision task, there is no interaction with the relative performance benefit provided by the use of spatialized auditory cues. [Work supported by ONR.

The Social Context of Undermining Behavior at Work

ERIC Educational Resources Information Center

Duffy, Michelle K.; Ganster, Daniel C.; Shaw, Jason D.; Johnson, Jonathan L.; Pagon, Milan

2006-01-01

We developed a fairness theory perspective to explain the experience of being "singled out" for social undermining from supervisors and coworkers, and tested our predictions across four distinct social contexts. We argued and predicted that attitudinal and behavioral reactions to undermining (from supervisors and coworkers) would be…

Investing in Teaching Development: Navigating Risk in a Research Intensive Institution

ERIC Educational Resources Information Center

Jawitz, Jeff; Perez, Teresa

2016-01-01

It is often assumed that academics working in a research intensive university are unlikely to invest in the professional development of their teaching. Institutional structures and culture tend to undermine investment in academics' teaching role. This study, conducted at the University of Cape Town, draws on an analysis of the environment within…

Rhetoric and Gender in Jane Austen's "Persuasion."

ERIC Educational Resources Information Center

Walzer, Arthur E.

1995-01-01

Argues for a reading of Jane Austen's "Persuasion" that undermines Joseph Duffy's reading of the novel as a commentary on shifting social class structures, and which bolsters Nancy Armstrong's reading as a commentary on female voice and the values of the domestic household. Interprets the novel in the light of 18th-century rhetorical…

Evolution of gossip-based indirect reciprocity on a bipartite network

PubMed Central

Giardini, Francesca; Vilone, Daniele

2016-01-01

Cooperation can be supported by indirect reciprocity via reputation. Thanks to gossip, reputations are built and circulated and humans can identify defectors and ostracise them. However, the evolutionary stability of gossip is allegedly undermined by the fact that it is more error-prone that direct observation, whereas ostracism could be ineffective if the partner selection mechanism is not robust. The aim of this work is to investigate the conditions under which the combination of gossip and ostracism might support cooperation in groups of different sizes. We are also interested in exploring the extent to which errors in transmission might undermine the reliability of gossip as a mechanism for identifying defectors. Our results show that a large quantity of gossip is necessary to support cooperation, and that group structure can mitigate the effects of errors in transmission. PMID:27885256

Evolution of gossip-based indirect reciprocity on a bipartite network.

PubMed

Giardini, Francesca; Vilone, Daniele

2016-11-25

Cooperation can be supported by indirect reciprocity via reputation. Thanks to gossip, reputations are built and circulated and humans can identify defectors and ostracise them. However, the evolutionary stability of gossip is allegedly undermined by the fact that it is more error-prone that direct observation, whereas ostracism could be ineffective if the partner selection mechanism is not robust. The aim of this work is to investigate the conditions under which the combination of gossip and ostracism might support cooperation in groups of different sizes. We are also interested in exploring the extent to which errors in transmission might undermine the reliability of gossip as a mechanism for identifying defectors. Our results show that a large quantity of gossip is necessary to support cooperation, and that group structure can mitigate the effects of errors in transmission.

Evolution of gossip-based indirect reciprocity on a bipartite network

NASA Astrophysics Data System (ADS)

Giardini, Francesca; Vilone, Daniele

2016-11-01

Cooperation can be supported by indirect reciprocity via reputation. Thanks to gossip, reputations are built and circulated and humans can identify defectors and ostracise them. However, the evolutionary stability of gossip is allegedly undermined by the fact that it is more error-prone that direct observation, whereas ostracism could be ineffective if the partner selection mechanism is not robust. The aim of this work is to investigate the conditions under which the combination of gossip and ostracism might support cooperation in groups of different sizes. We are also interested in exploring the extent to which errors in transmission might undermine the reliability of gossip as a mechanism for identifying defectors. Our results show that a large quantity of gossip is necessary to support cooperation, and that group structure can mitigate the effects of errors in transmission.

Does hospital competition harm equity? Evidence from the English National Health Service.

PubMed

Cookson, Richard; Laudicella, Mauro; Li Donni, Paolo

2013-03-01

Increasing evidence shows that hospital competition under fixed prices can improve quality and reduce cost. Concerns remain, however, that competition may undermine socio-economic equity in the utilisation of care. We test this hypothesis in the context of the pro-competition reforms of the English National Health Service progressively introduced from 2004 to 2006. We use a panel of 32,482 English small areas followed from 2003 to 2008 and a difference in differences approach. The effect of competition on equity is identified by the interaction between market structure, small area income deprivation and year. We find a negative association between market competition and elective admissions in deprived areas. The effect of pro-competition reform was to reduce this negative association slightly, suggesting that competition did not undermine equity. Copyright © 2012 Elsevier B.V. All rights reserved.

Continental-scale temperature covariance in proxy reconstructions and climate models

NASA Astrophysics Data System (ADS)

Hartl-Meier, Claudia; Büntgen, Ulf; Smerdon, Jason; Zorita, Eduardo; Krusic, Paul; Ljungqvist, Fredrik; Schneider, Lea; Esper, Jan

2017-04-01

Inter-continental temperature variability over the past millennium has been reported to be more coherent in climate model simulations than in multi-proxy-based reconstructions, a finding that undermines the representation of spatial variability in either of these approaches. We assess the covariance of summer temperatures among Northern Hemisphere continents by comparing tree-ring based temperature reconstructions with state-of-the-art climate model simulations over the past millennium. We find inter-continental temperature covariance to be larger in tree-ring-only reconstructions compared to those derived from multi-proxy networks, thus enhancing the agreement between proxy- and model-based spatial representations. A detailed comparison of simulated temperatures, however, reveals substantial spread among the models. Over the past millennium, inter-continental temperature correlations are driven by the cooling after major volcanic eruptions in 1257, 1452, 1601, and 1815. The coherence of these synchronizing events appears to be elevated in several climate simulations relative to their own covariance baselines and the proxy reconstructions, suggesting these models overestimate the amplitude of cooling in response to volcanic forcing at large spatial scales.

Distinct roles of basal forebrain cholinergic neurons in spatial and object recognition memory.

PubMed

Okada, Kana; Nishizawa, Kayo; Kobayashi, Tomoko; Sakata, Shogo; Kobayashi, Kazuto

2015-08-06

Recognition memory requires processing of various types of information such as objects and locations. Impairment in recognition memory is a prominent feature of amnesia and a symptom of Alzheimer's disease (AD). Basal forebrain cholinergic neurons contain two major groups, one localized in the medial septum (MS)/vertical diagonal band of Broca (vDB), and the other in the nucleus basalis magnocellularis (NBM). The roles of these cell groups in recognition memory have been debated, and it remains unclear how they contribute to it. We use a genetic cell targeting technique to selectively eliminate cholinergic cell groups and then test spatial and object recognition memory through different behavioural tasks. Eliminating MS/vDB neurons impairs spatial but not object recognition memory in the reference and working memory tasks, whereas NBM elimination undermines only object recognition memory in the working memory task. These impairments are restored by treatment with acetylcholinesterase inhibitors, anti-dementia drugs for AD. Our results highlight that MS/vDB and NBM cholinergic neurons are not only implicated in recognition memory but also have essential roles in different types of recognition memory.

Undermining the rules in home care services for the elderly in Norway: flexibility and cooperation.

PubMed

Wollscheid, Sabine; Eriksen, John; Hallvik, Jørgen

2013-06-01

This study explores the provision of home care services (home nursing and domiciliary help) for the elderly in Norwegian municipalities with purchaser-provider split model. The study draws on the assumption that flexibility in adjusting services to the care receivers' needs, and cooperation between provider and purchasers are indicators of good quality of care. Data were collected through semi-structured telephone interviews with 22 team leaders of provider units in nine municipalities. Data were collected in 2008-2009. The study has been approved by the Norwegian Social Science Data Services. We identified four different ways of organising home care services under a purchaser-provider split model: Provider empowerment, New Public Management, Vague instructions and undermining the rules. High flexibility in providing care and cooperation with the purchaser unit were identified by the team leaders as characteristics for good care. Our findings suggest that the care providers use individual strategies that allow flexibility and cooperation rather than rigidly abiding to the regulations the purchaser-provider split models implies. Ironically, in provider units where the 'rules were undermined', the informants (team leaders of provider units) seemed to be most satisfied with the quality of home care that they delivered. © 2012 Nordic College of Caring Science.

Analysis of Bilateral Effects between Social Undermining and Co-Creation among University Faculty Members

ERIC Educational Resources Information Center

Taherpour, Fatima; Rajaeepour, Saeed; Siadat, Ali; Kazemi, Iraj

2016-01-01

Understanding the social undermining is increasing important in organizational literature both because of its relation with job performance and because of its collective cost to individuals and organizations. This article argued that social undermining can effect on co-creation among faculty members. The study adopted a descriptive-correlational…

75 FR 45043 - Continuation of the National Emergency With Respect to the Actions of Certain Persons to...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-30

... to the Actions of Certain Persons to Undermine the Sovereignty of Lebanon or Its Democratic Processes... Persons to Undermine the Sovereignty of Lebanon or Its Democratic Processes and Institutions On August 1... measures blocking the property of certain persons undermining the sovereignty of Lebanon or its democratic...

Tag-mediated cooperation with non-deterministic genotype-phenotype mapping

NASA Astrophysics Data System (ADS)

Zhang, Hong; Chen, Shu

2016-01-01

Tag-mediated cooperation provides a helpful framework for resolving evolutionary social dilemmas. However, most of the previous studies have not taken into account genotype-phenotype distinction in tags, which may play an important role in the process of evolution. To take this into consideration, we introduce non-deterministic genotype-phenotype mapping into a tag-based model with spatial prisoner's dilemma. By our definition, the similarity between genotypic tags does not directly imply the similarity between phenotypic tags. We find that the non-deterministic mapping from genotypic tag to phenotypic tag has non-trivial effects on tag-mediated cooperation. Although we observe that high levels of cooperation can be established under a wide variety of conditions especially when the decisiveness is moderate, the uncertainty in the determination of phenotypic tags may have a detrimental effect on the tag mechanism by disturbing the homophilic interaction structure which can explain the promotion of cooperation in tag systems. Furthermore, the non-deterministic mapping may undermine the robustness of the tag mechanism with respect to various factors such as the structure of the tag space and the tag flexibility. This observation warns us about the danger of applying the classical tag-based models to the analysis of empirical phenomena if genotype-phenotype distinction is significant in real world. Non-deterministic genotype-phenotype mapping thus provides a new perspective to the understanding of tag-mediated cooperation.

Do Sons or Daughters Give More Money to Parents in Urban China?

ERIC Educational Resources Information Center

Xie, Yu; Zhu, Haiyan

2009-01-01

The patriarchal structure of the traditional Chinese family suggests that sons, more than daughters, provide financial support to elderly parents. The norm of receiving support in old age primarily from sons, however, may have been undermined by dramatic demographic, economic, and cultural changes occurring over the last several decades in China,…

Reaching and Teaching Students in Poverty: Strategies for Erasing the Opportunity Gap. Second Edition. Multicultural Education Series

ERIC Educational Resources Information Center

Gorski, Paul C.

2017-01-01

This influential book describes the knowledge and skills teachers and school administrators need to recognize and combat bias and inequity that undermine educational engagement for students experiencing poverty. The Second Edition features two new chapters--"Embracing a Structural View of Poverty and Education: Ditching Deficit Ideology and…

Universities on the Market: Academic Capitalism as a Challenge and a Window of Opportunity

ERIC Educational Resources Information Center

Demin, M. R.

2017-01-01

The modern university and the academic profession itself are facing new challenges: First, the increasing complexity of labor markets and globalization are undermining the structure of the academic profession, and secondly, the rise in cost of university research calls into question the autonomy of the university. The internationalization of the…

Climatic vulnerability of the world’s freshwater and marine fishes

NASA Astrophysics Data System (ADS)

Comte, Lise; Olden, Julian D.

2017-10-01

Climate change is a mounting threat to biological diversity, compromising ecosystem structure and function, and undermining the delivery of essential services worldwide. As the magnitude and speed of climate change accelerates, greater understanding of the taxonomy and geography of climatic vulnerability is critical to guide effective conservation action. However, many uncertainties remain regarding the degree and variability of climatic risk within entire clades and across vast ecosystem boundaries. Here we integrate physiological estimates of thermal sensitivity for 2,960 ray-finned fishes with future climatic exposure, and demonstrate that global patterns of vulnerability differ substantially between freshwater and marine realms. Our results suggest that climatic vulnerability for freshwater faunas will be predominantly determined by elevated levels of climatic exposure predicted for the Northern Hemisphere, whereas marine faunas in the tropics will be the most at risk, reflecting their higher intrinsic sensitivity. Spatial overlap between areas of high physiological risk and high human impacts, together with evidence of low past rates of evolution in upper thermal tolerance, highlights the urgency of global conservation actions and policy initiatives if harmful climate effects on the world’s fishes are to be mitigated in the future.

"What Turns You On!": An Exploration of Urban South African Xhosa and Zulu Youth Texts

ERIC Educational Resources Information Center

Finlayson, Rosalie; Slabbert, Sarah

2003-01-01

The status of the current standard African languages has been seriously undermined by factors such as the association of the standardisation process with colonial and neo-colonial structures, the lack of function of the standards and the rise of high status non-standard urban varieties. This paper describes the process leading to and some…

What is ontic structural realism?

NASA Astrophysics Data System (ADS)

Ainsworth, Peter Mark

In recent years a doctrine known as ontic structural realism (OSR) has achieved a degree of notoriety, but many people remain confused as to what exactly the doctrine amounts. In this paper three main variants of OSR are defined and discussed: (i) OSR1, which is the view that relations are ontologically primitive but objects and properties are not; (ii) OSR2, which is the view that objects and relations are ontologically primitive but properties are not; (iii) OSR3, which is the view that properties and relations are ontologically primitive but objects are not. Proponents of OSR claim that it is a "naturalistic" metaphysics, arguing that metaphysical views that take objects and/or properties as ontologically primitive are undermined by contemporary physics. In this paper it is argued that OSR1 and OSR2 are themselves undermined by contemporary physics. On the other hand, it is also argued that considerations about the objects of quantum mechanics and general relativity do seem to suggest that we should abandon some of our "common-sense" metaphysical intuitions, and that OSR3 is one of the metaphysical views that is compatible with what these theories seem to tell us about fundamental ontology.

In the land of the free, interdependent action undermines motivation.

PubMed

Hamedani, Maryam G; Markus, Hazel Rose; Fu, Alyssa S

2013-02-01

Today's most pressing social challenges require people to recognize their shared fate and work together--to think and act interdependently. In the three studies reported here, we found that appeals for increased interdependence may undermine the very motivation they seek to inspire. We examined the hypothesis that invoking interdependent action undermines motivation for chronically independent European Americans but not for bicultural Asian Americans who are both chronically independent and chronically interdependent. Studies 1 and 2 demonstrated that priming interdependent rather than independent action undermined European Americans' motivation to perform challenging mental and physical tasks. Study 3 showed that framing an appeal for environmental sustainability in terms of interdependent rather than independent action led to decreased motivation and resource allocation among European Americans. Motivation was not undermined for Asian Americans, which reveals how behavior is divergently shaped, in the land of the free, by foundational sociocultural schemas of independence and interdependence. This research has the novel implication that it may be necessary to invoke independent behaviors in order to successfully motivate interdependence.

Why do we lose protected areas? Factors influencing protected area downgrading, downsizing and degazettement in the tropics and subtropics.

PubMed

Symes, William S; Rao, Madhu; Mascia, Michael B; Carrasco, L Roman

2016-02-01

Protected areas (PAs) are an essential tool for the conservation of biodiversity globally. Previous studies have focussed on the effectiveness of PAs and the design of optimal PA networks. However, not all PAs remain intact permanently; many PAs undergo downgrading, downsizing and/or degazettement (PADDD), a fact largely ignored until recently. The drivers of enacted PADDD events and the factors influencing its spatial occurrence are poorly understood, potentially undermining the efficacy of PAs and PA networks. Here we examine the spatial relationship between PADDD and economic, demographic and structural variables, using a 110-year data set of 342 enacted PADDD events across 44 countries in the tropics and subtropics. We find that the probability of an enacted PADDD event increases with the size of the PA and through a synergistic interaction between PA size and local population densities. Our results are robust to the under-reporting of enacted PADDD events that occur among smaller PAs and in regions with lower population density. We find an economic motive for PADDD events, given that the opportunity costs associated with larger PAs are higher, on average, than smaller PAs. Our findings suggest a need for conservation practitioners to better consider PA characteristics, as well as the social, economic and political context in which PAs are situated, to aid the creation of more efficient and sustainable PA networks. In particular, the dynamics of enacted PADDD events highlight the need to explicitly consider PA robustness as a core component of systematic conservation planning for PA networks. © 2015 John Wiley & Sons Ltd.

[Identification of ecological corridors for Tibetan antelope and assessment of their human disturbances in the alpine desert of Qinghai-Tibet Plateau].

PubMed

Zhuge, Hai-jin; Lin, Dan-qi; Li, Xiao-wen

2015-08-01

The alpine desert of Qinghai-Tibet Plateau (QTP) provides the largest habitats for those endangered ungulates (e.g., Tibetan antelope, Tibetan Kiang and wild yak) on the earth. However, human disturbance especially infrastructure constructions (e.g., railway & highway) has increasingly fragmented the habitats of those endangered ungulates by disturbing and interrupting their ecological corridors for their seasonal migration. Aiming at identifying the potential ecological corridors for Tibetan antelope, a GIS-based model-Linkage Mapper was used to model and detect the potential ecological corridors of Tibetan antelope based on the principle of least cost path. Three categories of ecological corridors, i. e., closed (inside reserves), linking (linking the reserves) and open (starting from reserve but ending outside) corridors were distinguished by their spatial interactions with existing major national nature reserves (i.e., Altun, Kekexili and Qiangtang NNRs) in the alpine desert of QTP, and their spatial patterns, conservation status associated with human disturbance were also examined. Although our research indicated a general ecological integration of both habitats and ecological corridors in the alpine desert ecosystem, increasing human disturbance should not be ignored, which particularly partially undermined the functioning of those ecological corridors linking the nature reserves. Considering disadvantages of prevailing separate administrative structure of nature reserve on the effective conservation of ecological corridors for those endangered ungulates, a coordinative conservation network among these major national nature reserves should be established to ensure the unified trans-boundary conservation efforts and to enhance its overall conservation efficacy by sharing information, knowledge and optimizing conservation resources.

Sexual networks: measuring sexual selection in structured, polyandrous populations.

PubMed

McDonald, Grant C; James, Richard; Krause, Jens; Pizzari, Tommaso

2013-03-05

Sexual selection is traditionally measured at the population level, assuming that populations lack structure. However, increasing evidence undermines this approach, indicating that intrasexual competition in natural populations often displays complex patterns of spatial and temporal structure. This complexity is due in part to the degree and mechanisms of polyandry within a population, which can influence the intensity and scale of both pre- and post-copulatory sexual competition. Attempts to measure selection at the local and global scale have been made through multi-level selection approaches. However, definitions of local scale are often based on physical proximity, providing a rather coarse measure of local competition, particularly in polyandrous populations where the local scale of pre- and post-copulatory competition may differ drastically from each other. These limitations can be solved by social network analysis, which allows us to define a unique sexual environment for each member of a population: 'local scale' competition, therefore, becomes an emergent property of a sexual network. Here, we first propose a novel quantitative approach to measure pre- and post-copulatory sexual selection, which integrates multi-level selection with information on local scale competition derived as an emergent property of networks of sexual interactions. We then use simple simulations to illustrate the ways in which polyandry can impact estimates of sexual selection. We show that for intermediate levels of polyandry, the proposed network-based approach provides substantially more accurate measures of sexual selection than the more traditional population-level approach. We argue that the increasing availability of fine-grained behavioural datasets provides exciting new opportunities to develop network approaches to study sexual selection in complex societies.

Navigating identity, territorial stigma, and HIV care services in Vancouver, Canada: A qualitative study.

PubMed

Collins, Alexandra B; Parashar, Surita; Closson, Kalysha; Turje, Rosalind Baltzer; Strike, Carol; McNeil, Ryan

2016-07-01

This study examines the influence of territorial stigma on access to HIV care and other support services. Qualitative interviews were conducted with thirty people living with HIV (PLHIV) who use drugs recruited from the Dr. Peter Centre (DPC), an HIV care facility located in Vancouver, Canada's West End neighbourhood that operates under a harm reduction approach. Findings demonstrated that territorial stigma can undermine access to critical support services and resources in spatially stigmatized neighbourhoods among PLHIV who use drugs who have relocated elsewhere. Furthermore, PLHIV moving from spatially stigmatized neighbourhoods - in this case, Vancouver's Downtown Eastside - to access HIV care services experienced tension with different groups at the DPC (e.g., men who have sex with me, people who use drugs), as these groups sought to define who constituted a'normative' client. Collectively, these findings demonstrate the urgent need to consider the siting of HIV care services as the epidemic evolves. Copyright © 2016 Elsevier Ltd. All rights reserved.

Extrinsic and intrinsic motivation at 30: Unresolved scientific issues.

PubMed

Reiss, Steven

2005-01-01

The undermining effect of extrinsic reward on intrinsic motivation remains unproven. The key unresolved issues are construct invalidity (all four definitions are unproved and two are illogical); measurement unreliability (the free-choice measure requires unreliable, subjective judgments to infer intrinsic motivation); inadequate experimental controls (negative affect and novelty, not cognitive evaluation, may explain "undermining" effects); and biased metareviews (studies with possible floor effects excluded, but those with possible ceiling effects included). Perhaps the greatest error with the undermining theory, however, is that it does not adequately recognize the multifaceted nature of intrinsic motivation (Reiss, 2004a). Advice to limit the use of applied behavior analysis based on "hidden" undermining effects is ideologically inspired and is unsupported by credible scientific evidence.

'It's more about the heroin': injection drug users' response to an overdose warning campaign in a Canadian setting.

PubMed

Kerr, Thomas; Small, Will; Hyshka, Elaine; Maher, Lisa; Shannon, Kate

2013-07-01

To assess heroin injectors' perceptions of and responses to a warning issued by public health officials regarding high-potency heroin and increases in fatal overdoses. Semi-structured qualitative interviews. Vancouver, Canada. Eighteen active heroin injectors. Semi-structured interview guide focussing on heroin injectors' perceptions of and responses to the overdose warning, including reasons for failing to adhere to risk reduction recommendations. Although nearly all participants were aware of the warning, their recollections of the message and the timing of its release were obscured by on-going social interactions within the drug scene focussed on heroin quality. Many injection drug users reported seeking the high potency heroin and nearly all reported no change in overdose risk behaviours. Responses to the warning were shaped by various social, economic and structural forces that interacted with individual behaviour and undermined efforts to promote behavioural change, including sales tactics employed by dealers, poverty, the high cost and shifting quality of available heroin, and risks associated with income-generating activities. Individual-level factors, including emotional suffering, withdrawal, entrenched injecting routines, perceived invincibility and the desire for intense intoxication also undermined risk reduction messages. Among heroin injectors in British Columbia, a 2011 overdose warning campaign appeared to be of limited effectiveness and also produced unintended negative consequences that exacerbated overdose risk. © 2013 Society for the Study of Addiction.

Consultants as victims of bullying and undermining: a survey of Royal College of Obstetricians and Gynaecologists consultant experiences

PubMed Central

Shabazz, Tariq; Parry-Smith, William; Oates, Sharon; Henderson, Steven; Mountfield, Joanna

2016-01-01

Objective To explore incidents of bullying and undermining among obstetrics and gynaecology (O&G) consultants in the UK, to add another dimension to previous research and assist in providing a more holistic understanding of the problem in medicine. Design Questionnaire survey. Setting Royal College of Obstetricians and Gynaecologists (RCOG). Participants O&G consultant members/fellows of the RCOG working in the UK. Main outcome measures Measures included a typology of 4 bullying and undermining consequences from major to coping. Results There was a 28% (664) response rate of whom 44% (229) responded that they had been persistently bullied or undermined. Victims responded that bullying and undermining is carried out by those senior or at least close in the hierarchy. Of the 278 consultants who answered the question on ‘frequency of occurrence’, 50% stated that bullying and undermining occurs on half, or more, of all encounters with perpetrators and two-thirds reported that it had lasted more than 3 years. The reported impact on professional and personal life spans a wide spectrum from suicidal ideation, depression and sleep disturbance, and a loss of confidence. Over half reported problems that could compromise patient care. When victims were asked if the problem was being addressed, 73% of those that responded stated that it was not. Conclusions Significant numbers of consultants in O&G in the UK are victims of bullying and undermining behaviour that puts their own health and patient care at risk. New interventions to tackle the problem, rather than its consequences, are required urgently, together with greater commitment to supporting such interventions. PMID:27324715

Consultants as victims of bullying and undermining: a survey of Royal College of Obstetricians and Gynaecologists consultant experiences.

PubMed

Shabazz, Tariq; Parry-Smith, William; Oates, Sharon; Henderson, Steven; Mountfield, Joanna

2016-06-20

To explore incidents of bullying and undermining among obstetrics and gynaecology (O&G) consultants in the UK, to add another dimension to previous research and assist in providing a more holistic understanding of the problem in medicine. Questionnaire survey. Royal College of Obstetricians and Gynaecologists (RCOG). O&G consultant members/fellows of the RCOG working in the UK. Measures included a typology of 4 bullying and undermining consequences from major to coping. There was a 28% (664) response rate of whom 44% (229) responded that they had been persistently bullied or undermined. Victims responded that bullying and undermining is carried out by those senior or at least close in the hierarchy. Of the 278 consultants who answered the question on 'frequency of occurrence', 50% stated that bullying and undermining occurs on half, or more, of all encounters with perpetrators and two-thirds reported that it had lasted more than 3 years. The reported impact on professional and personal life spans a wide spectrum from suicidal ideation, depression and sleep disturbance, and a loss of confidence. Over half reported problems that could compromise patient care. When victims were asked if the problem was being addressed, 73% of those that responded stated that it was not. Significant numbers of consultants in O&G in the UK are victims of bullying and undermining behaviour that puts their own health and patient care at risk. New interventions to tackle the problem, rather than its consequences, are required urgently, together with greater commitment to supporting such interventions. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Sand waves in environmental flows: Insights gained by coupling large-eddy simulation with morphodynamics

NASA Astrophysics Data System (ADS)

Sotiropoulos, Fotis; Khosronejad, Ali

2016-02-01

Sand waves arise in subaqueous and Aeolian environments as the result of the complex interaction between turbulent flows and mobile sand beds. They occur across a wide range of spatial scales, evolve at temporal scales much slower than the integral scale of the transporting turbulent flow, dominate river morphodynamics, undermine streambank stability and infrastructure during flooding, and sculpt terrestrial and extraterrestrial landscapes. In this paper, we present the vision for our work over the last ten years, which has sought to develop computational tools capable of simulating the coupled interactions of sand waves with turbulence across the broad range of relevant scales: from small-scale ripples in laboratory flumes to mega-dunes in large rivers. We review the computational advances that have enabled us to simulate the genesis and long-term evolution of arbitrarily large and complex sand dunes in turbulent flows using large-eddy simulation and summarize numerous novel physical insights derived from our simulations. Our findings explain the role of turbulent sweeps in the near-bed region as the primary mechanism for destabilizing the sand bed, show that the seeds of the emergent structure in dune fields lie in the heterogeneity of the turbulence and bed shear stress fluctuations over the initially flatbed, and elucidate how large dunes at equilibrium give rise to energetic coherent structures and modify the spectra of turbulence. We also discuss future challenges and our vision for advancing a data-driven simulation-based engineering science approach for site-specific simulations of river flooding.

Disowned recollections: denying true experiences undermines belief in occurrence but not judgments of remembering.

PubMed

Mazzoni, Giuliana; Clark, Andrew; Nash, Robert A

2014-01-01

Recent research findings have illustrated that false memories induced in the laboratory can be dissociated from the beliefs that the events had in fact occurred. In this study we assessed whether this dissociability is a quality peculiar to false memory, or whether it represents a general characteristic of autobiographical memory. To this end we examined whether people can be induced to stop believing in memories for true experiences. Participants observed and performed simple actions, and were later falsely informed that they had not performed some of them--that false memories for these actions had been implanted through the use of fabricated evidence. Before and after receiving this misinformation, participants rated their belief in and memory of performing those actions, other actions that they had also performed, and actions that they had not performed. Whereas the misinformation substantially undermined participants' beliefs in the specific performed actions about which they had been misinformed, it had little effect on their endorsement of remembering those actions. The misinformation thus boosted the proportion of occasions in which participants rated their memories as stronger than their beliefs, and it weakened the correlation between belief and memory ratings. Thus, this study provides the first experimental demonstration of non-believed memories of true experiences. We discuss our findings with reference to the small literature concerning the use of socially-communicated misinformation to undermine event memories, and with reference to the structure of autobiographical memory. Copyright © 2013 Elsevier B.V. All rights reserved.

The Cuban health care system and factors currently undermining it.

PubMed

Nayeri, K

1995-08-01

This paper explores the dynamics of health and health care in Cuba during a period of severe crisis by placing it within its economic, social, and political context using a comparative historical approach. It outlines Cuban achievements in health care as a consequence of the socialist transformations since 1959, noting the full commitment by the Cuban state, the planned economy, mass participation, and a self-critical, working class perspective as crucial factors. The roles of two external factors, the U.S. economic embargo and the Council of Mutual Economic Cooperation (CMEA), are explored in shaping the Cuban society and economy, including its health care system. It is argued that the former has hindered health efforts in Cuba. The role of the latter is more complex. While the CMEA was an important source for economic growth, Cuban relations with the Soviet bloc had a damaging effect on the development of socialism in Cuba. The adoption of the Soviet model of economic development fostered bureaucracy and demoralization of Cuban workers. As such, it contributed to two internal factors that have undermined further social progress including in health care: low productivity of labor and the growth of bureaucracy. While the health care system is still consistently supported by public policy and its structure is sound, economic crisis undermines its material and moral foundations and threatens its achievements. The future of the current Cuban health care system is intertwined with the potentials for its socialist development.

Sidewalk undermining studies : final report.

DOT National Transportation Integrated Search

1979-01-01

The report summarizes some five years of studies on the highly expensive sidewalk undermining problem which plagues the Northern Virginia area. Included are studies of sidewalk replacement techniques, of the soils and geometric conditions contributin...

The system-stabilizing role of identity management strategies: social creativity can undermine collective action for social change.

PubMed

Becker, Julia C

2012-10-01

Three studies were conducted to examine whether, in an event of negative distinctiveness, engaging in 1 of the 3 identity management strategies of social creativity can undermine group member's intentions to engage in collective action. Study 1a (N = 55) and Study 1b (N = 58) illustrated that selecting a new (complementary) comparison dimension undermined middle-class people's and women's intention to participate in collective action. Study 1c (N = 74) and Study 1d (N = 126) revealed that a downward comparison undermined collective action intentions among unemployed people and women. Study 1e (N = 69) and Study 1f (N = 110) showed that a positive redefinition of an externally imposed negative group attribute did not diminish collective action intentions among immigrants and women. Study 2 (N = 99) illustrated that an alternative operationalization of revaluation of the attribute, namely, downplaying the status-defining attribute, undermined collective action among students. Study 2 and Study 3 (N = 95) consistently illustrated that reduced levels of group-relative deprivation mediated the negative relation between the social creativity strategies and collective action intentions. Implications for social change are discussed.

Nutrient Mitigation Efficiency in Agricultural Drainage Ditches: An Influence of Landscape Management.

PubMed

Iseyemi, Oluwayinka O; Farris, Jerry L; Moore, Matthew T; Choi, Seo-Eun

2016-06-01

Drainage systems are integral parts of agricultural landscapes and have the ability to intercept nutrient loading from runoff to surface water. This study investigated nutrient removal efficiency within replicated experimental agricultural drainage ditches during a simulated summer runoff event. Study objectives were to examine the influence of routine mowing of vegetated ditches on nutrient mitigation and to assess spatial transformation of nutrients along ditch length. Both mowed and unmowed ditch treatments decreased NO3 (-)-N by 79 % and 94 % and PO4 (3-) by 95 % and 98 %, respectively, with no significant difference in reduction capacities between the two treatments. This suggests occasional ditch mowing as a management practice would not undermine nutrient mitigation capacity of vegetated drainage ditches.

GIS, modeling, and politics: on the tensions of collaborative decision support.

PubMed

Ramsey, Kevin

2009-05-01

A tension exists at the heart of efforts to support collaboration with GIS. Many scholars and practitioners seek to support two separate objectives: (1) problem solving and (2) the exploration of diverse problem understandings. GIS applications designed for problem solving often pre-define the problem space by structuring the kind of information that can be considered or the way in which the problem is conceptualized. In doing so, they necessarily privilege particular perspectives and understandings of the problem while marginalizing others. As a result, these initiatives undermine their second objective. This is problematic in the context of contentious environmental decisions which have broad-reaching impacts on people with diverse perspectives and interests. In such contexts, I argue that equitable collaboration is impossible without first emphasizing the exploration of diverse problem understandings. I support this argument theoretically by turning to the literatures on collaborative planning and spatial decision support, and empirically in my analysis of a case study of an effort to construct a GIS for supporting collaborative water resource management in rural Idaho. Reflecting upon the case, I provide a set of recommendations to those seeking to better negotiate the tensions of supporting collaboration with GIS in the context of contentious environmental and natural resource decisions.

A hydromorphological framework for the evaluation of e-flows

NASA Astrophysics Data System (ADS)

Bussettini, Martina; Rinaldi, Massimo; Grant, Gordon

2017-04-01

Anthropogenic alteration of hydromorphological processes in rivers is a major factor that diminishes river health and undermines environmental objectives envisaged by river protection policies. Specifying environmental flows to address those impacts can be a key strategy for the maintenance of functional river processes and the achievement of those objectives. Environmental flows are determined by various methods and approaches, based primarily on hydrological and/or hydraulic evaluations, although holistic methodologies, considering the many interacting factors that structure aquatic ecosystems, including sediments, are increasingly used. Hydrological and geomorphological processes are highly coupled and any change in one typically affects the other. The coupling varies over different spatial and temporal scales, and changing either hydrological or geomorphological processes can result in alteration of river habitats, ultimately impacting ecological processes. In spite of these linkages, current restoration approaches typically focus only on changes on hydrological regime as a means promoting ecological enhancements. Neglecting sediment transport and its interaction with flow in shaping riverine habitats is likely to results not only in minor or no enhancements in the ecology, but may also increase the costs of water use. A more integrated view of how human activities jointly affect sediment regime, river morphology and river flows is therefore needed in order to determine the most effective actions to rehabilitate river processes to desired states. These states involve considerations of the combination of intrinsic ("natural") conditions (e.g. river sensitivity and morphological potential, off-site conditions) and socio-economic constraints. The evaluation of such factors, the analysis of different scenarios, and the selection of appropriate actions require the contextualization of river reaches within a wider spatial-temporal hydromorphological framework. Here we present such a general multiscale, process-based hydromorphological framework, and discuss its application to the problem of how best to analyse and estimate e-flows.

What are we protecting? Fisher behavior and the unintended consequences of spatial closures as a fishery management tool.

PubMed

Abbott, Joshua K; Haynie, Alan C

2012-04-01

Spatial closures like marine protected areas (MPAs) are prominent tools for ecosystem-based management in fisheries. However, the adaptive behavior of fishermen, the apex predator in the ecosystem, to MPAs may upset the balance of fishing impacts across species. While ecosystem-based management (EBM) emphasizes the protection of all species in the environment, the weakest stock often dominates management attention. We use data before and after the implementation of large spatial closures in a North Pacific trawl fishery to show how closures designed for red king crab protection spurred dramatic increases in Pacific halibut bycatch due to both direct displacement effects and indirect effects from adaptations in fishermen's targeting behavior. We identify aspects of the ecological and economic context of the fishery that contributed to these surprising behaviors, noting that many multispecies fisheries are likely to share these features. Our results highlight the need either to anticipate the behavioral adaptations of fishermen across multiple species in reserve design, a form of implementation error, or to design management systems that are robust to these adaptations. Failure to do so may yield patterns of fishing effort and mortality that undermine the broader objectives of multispecies management and potentially alter ecosystems in profound ways.

76 FR 43799 - Continuation of the National Emergency With Respect to the Former Liberian Regime of Charles Taylor

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-21

... from Liberia and secreting of Liberian funds and property, which have undermined Liberia's transition... that continues to undermine Liberia's transformation and recovery. Because the actions and policies of...

Applicability of radar subsurface profiling in estimating sidewalk undermining.

DOT National Transportation Integrated Search

1979-01-01

An evaluation was made of the applicability of the geophysical technique of radar subsurface profiling to estimating the extent of sidewalk undermining. It was found that there is a distinct difference between the observed radar echo patterns of a no...

Impact of HIV-related stigma on treatment adherence: systematic review and meta-synthesis

PubMed Central

Katz, Ingrid T; Ryu, Annemarie E; Onuegbu, Afiachukwu G; Psaros, Christina; Weiser, Sheri D; Bangsberg, David R; Tsai, Alexander C

2013-01-01

Introduction Adherence to HIV antiretroviral therapy (ART) is a critical determinant of HIV-1 RNA viral suppression and health outcomes. It is generally accepted that HIV-related stigma is correlated with factors that may undermine ART adherence, but its relationship with ART adherence itself is not well established. We therefore undertook this review to systematically assess the relationship between HIV-related stigma and ART adherence. Methods We searched nine electronic databases for published and unpublished literature, with no language restrictions. First we screened the titles and abstracts for studies that potentially contained data on ART adherence. Then we reviewed the full text of these studies to identify articles that reported data on the relationship between ART adherence and either HIV-related stigma or serostatus disclosure. We used the method of meta-synthesis to summarize the findings from the qualitative studies. Results Our search protocol yielded 14,854 initial records. After eliminating duplicates and screening the titles and abstracts, we retrieved the full text of 960 journal articles, dissertations and unpublished conference abstracts for review. We included 75 studies conducted among 26,715 HIV-positive persons living in 32 countries worldwide, with less representation of work from Eastern Europe and Central Asia. Among the 34 qualitative studies, our meta-synthesis identified five distinct third-order labels through an inductive process that we categorized as themes and organized in a conceptual model spanning intrapersonal, interpersonal and structural levels. HIV-related stigma undermined ART adherence by compromising general psychological processes, such as adaptive coping and social support. We also identified psychological processes specific to HIV-positive persons driven by predominant stigmatizing attitudes and which undermined adherence, such as internalized stigma and concealment. Adaptive coping and social support were critical determinants of participants’ ability to overcome the structural and economic barriers associated with poverty in order to successfully adhere to ART. Among the 41 quantitative studies, 24 of 33 cross-sectional studies (71%) reported a positive finding between HIV stigma and ART non-adherence, while 6 of 7 longitudinal studies (86%) reported a null finding (Pearson's χ 2=7.7; p=0.005). Conclusions We found that HIV-related stigma compromised participants’ abilities to successfully adhere to ART. Interventions to reduce stigma should target multiple levels of influence (intrapersonal, interpersonal and structural) in order to have maximum effectiveness on improving ART adherence. PMID:24242258

Will Biomedical Enhancements Undermine Solidarity, Responsibility, Equality and Autonomy?

PubMed Central

Lev, Ori

2009-01-01

Prominent thinkers such as Jurgen Habermas and Michael Sandel are warning that biomedical enhancements will undermine fundamental political values. Yet, whether biomedical enhancements will undermine such values depends on how biomedical enhancements will function, how they will be administered and to whom. Since only few enhancements are obtainable, it is difficult to tell whether their predictions are sound. Nevertheless, such warnings are extremely valuable. As a society we must, at the very least, be aware of developments that could have harmful consequences. Indeed, if important values would be jeopardized, we should take appropriate measures to protect them. This paper focuses on four central values: solidarity, personal responsibility, equality and autonomy. It delineates the conditions under which biomedical enhancements would undermine these values. It also details the circumstances under which these values would be unaffected by enhancements as well as those under which they would be promoted. Specifying these conditions is valuable; it would enable society to prepare appropriate ethical guidelines and policy responses in advance. PMID:20002073

The reliability paradox: Why robust cognitive tasks do not produce reliable individual differences.

PubMed

Hedge, Craig; Powell, Georgina; Sumner, Petroc

2018-06-01

Individual differences in cognitive paradigms are increasingly employed to relate cognition to brain structure, chemistry, and function. However, such efforts are often unfruitful, even with the most well established tasks. Here we offer an explanation for failures in the application of robust cognitive paradigms to the study of individual differences. Experimental effects become well established - and thus those tasks become popular - when between-subject variability is low. However, low between-subject variability causes low reliability for individual differences, destroying replicable correlations with other factors and potentially undermining published conclusions drawn from correlational relationships. Though these statistical issues have a long history in psychology, they are widely overlooked in cognitive psychology and neuroscience today. In three studies, we assessed test-retest reliability of seven classic tasks: Eriksen Flanker, Stroop, stop-signal, go/no-go, Posner cueing, Navon, and Spatial-Numerical Association of Response Code (SNARC). Reliabilities ranged from 0 to .82, being surprisingly low for most tasks given their common use. As we predicted, this emerged from low variance between individuals rather than high measurement variance. In other words, the very reason such tasks produce robust and easily replicable experimental effects - low between-participant variability - makes their use as correlational tools problematic. We demonstrate that taking such reliability estimates into account has the potential to qualitatively change theoretical conclusions. The implications of our findings are that well-established approaches in experimental psychology and neuropsychology may not directly translate to the study of individual differences in brain structure, chemistry, and function, and alternative metrics may be required.

Understanding the challenges of service change – learning from acute pain services in the UK

PubMed Central

Powell, AE; Davies, HTO; Bannister, J; Macrae, WA

2009-01-01

Summary Objectives To explore organizational difficulties faced when implementing national policy recommendations in local contexts. Design Qualitative case study involving semi-structured interviews with health professionals and managers working in and around acute pain services. Setting Three UK acute hospital organizations. Main outcome measures Identification of the content, context and process factors impacting on the implementation of the national policy recommendations on acute pain services; insights into and deeper understanding of the generic obstacles to change facing service improvements. Results The process of implementing policy recommendations and improving services in each of the three organizations was undermined by multiple factors relating to: doubts and disagreements about the nature of the change; challenging local organizational contexts; and the beliefs, attitudes and responses of health professionals and managers. The impact of these factors was compounded by the interaction between them. Conclusions Local implementation of national policies aimed at service improvement can be undermined by multiple interacting factors. Particularly important are the pre-existing local organizational contexts and histories, and the deeply-ingrained attitudes, beliefs and assumptions of diverse staff groups. Without close attention to all of these underlying issues and how they interact in individual organizations against the background of local and national contexts, more resources or further structural change are unlikely to deliver the intended improvements in patient care. PMID:19208870

Dysfunctional health service conflict: causes and accelerants.

PubMed

Nelson, H Wayne

2012-01-01

This article examines the causes and accelerants of dysfunctional health service conflict and how it emerges from the health system's core hierarchical structures, specialized roles, participant psychodynamics, culture, and values. This article sets out to answer whether health care conflict is more widespread and intense than in other settings and if it is, why? To this end, health care power, gender, and educational status gaps are examined with an eye to how they undermine open communication, teamwork, and collaborative forms of conflict and spark a range of dysfunctions, including a pervasive culture of fear; the deny-and-defend lawsuit response; widespread patterns of hierarchical, generational, and lateral bullying; overly avoidant conflict styles among non-elite groups; and a range of other behaviors that lead to numerous human resource problems, including burnout, higher staff turnover, increased errors, poor employee citizenship behavior, patient dissatisfaction, increased patient complaints, and lawsuits. Bad patient outcomes include decreased compliance and increased morbidity and mortality. Health care managers must understand the root causes of these problems to treat them at the source and implement solutions that avoid negative conflict spirals that undermine organizational morale and efficiency.

77 FR 75702 - Supplemental Identification Information for 1 Individual Designated Pursuant to Executive Order...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-21

... of Persons Undermining the Sovereignty of Lebanon or Its Democratic Processes and Institutions... persons to undermine Lebanon's legitimate and democratically elected government or democratic institutions, to contribute to the deliberate breakdown in the rule of law in Lebanon, including through...

How Patronage Politics Undermines Parental Participation and Accountability: Community-Managed Schools in Honduras and Guatemala

ERIC Educational Resources Information Center

Altschuler, Daniel

2013-01-01

This article shows how patronage politics affects a popular international education model: community-managed schools (CMS). Focusing on Honduras's CMS initiative, PROHECO (Programa Hondureno de Educacion Comunitaria), I demonstrate how patronage can undermine CMS accountability. Whereas supporters argue that CMS increases accountability, partisan…

PAH molecular diagnostic ratios applied to atmospheric sources: a critical evaluation using two decades of source inventory and air concentration data from the UK.

PubMed

Katsoyiannis, Athanasios; Sweetman, Andrew J; Jones, Kevin C

2011-10-15

Molecular diagnostic ratios (MDRs)-the ratios of defined pairs of individual compounds-have been widely used as markers of different source categories of polycyclic aromatic hydrocarbons (PAHs). However, it is well-known that variations in combustion conditions and environmental degradation processes can cause substantial variability in the emission and degradation of individual compounds, potentially undermining the application of MDRs as reliable source apportionment tools. The United Kingdom produces a national inventory of atmospheric emissions of PAHs, and has an ambient air monitoring program at a range of rural, semirural, urban, and industrial sites. The inventory and the monitoring data are available over the past 20 years (1990-2010), a time frame that has seen known changes in combustion type and source. Here we assess 5 MDRs that have been used in the literature as source markers. We examine the spatial and temporal variability in the ratios and consider whether they are responsive to known differences in source strength and types between sites (on rural-urban gradients) and to underlying changes in national emissions since 1990. We conclude that the use of these 5 MDRs produces contradictory results and that they do not respond to known differences (in time and space) in atmospheric emission sources. For example, at a site near a motorway and far from other evident emission sources, the use of MDRs suggests "non-traffic" emissions. The ANT/(ANT + PHE) ratio is strongly seasonal at some sites; it is the most susceptible MDR to atmospheric processes, so these results illustrate how weathering in the environment will undermine the effectiveness of MDRs as markers of source(s). We conclude that PAH MDRs can exhibit spatial and temporal differences, but they are not valid markers of known differences in source categories and type. Atmospheric sources of PAHs in the UK are probably not dominated by any single clear and strong source type, so the mixture of PAHs in air is quickly "blended" away from the influence of the few major point sources which exist and further weathered in the environment by atmospheric reactions and selective loss processes.

Does red undermine individuals' intellectual performance? A test in China.

PubMed

Shi, Jiaxin; Zhang, Chao; Jiang, Feng

2015-02-01

Previous research shows that red impairs individuals' performance on challenging intellectual tasks in achievement situations. However, no research to date has examined this issue in Chinese society. In China, red has a positive connotation in general (unlike in the West), but also has a negative connotation for students, given that teachers mark incorrect answers in red (like in the West). Therefore, the question of whether red promotes or undermines intellectual performance for Chinese individuals needs to be tested. The present research investigated this and found, consistent with findings obtained in the West, that red undermined the intellectual performance of Chinese students. Future directions and potential mechanisms are discussed. © 2014 International Union of Psychological Science.

Comment on "The extent of forest in dryland biomes".

PubMed

Griffith, Daniel M; Lehmann, Caroline E R; Strömberg, Caroline A E; Parr, Catherine L; Pennington, R Toby; Sankaran, Mahesh; Ratnam, Jayashree; Still, Christopher J; Powell, Rebecca L; Hanan, Niall P; Nippert, Jesse B; Osborne, Colin P; Good, Stephen P; Anderson, T Michael; Holdo, Ricardo M; Veldman, Joseph W; Durigan, Giselda; Tomlinson, Kyle W; Hoffmann, William A; Archibald, Sally; Bond, William J

2017-11-17

Bastin et al (Reports, 12 May 2017, p. 635) infer forest as more globally extensive than previously estimated using tree cover data. However, their forest definition does not reflect ecosystem function or biotic composition. These structural and climatic definitions inflate forest estimates across the tropics and undermine conservation goals, leading to inappropriate management policies and practices in tropical grassy ecosystems. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Relational conceptions of paternalism: a way to rebut nanny-state accusations and evaluate public health interventions.

PubMed

Carter, S M; Entwistle, V A; Little, M

2015-08-01

'Nanny-state' accusations can function as powerful rhetorical weapons against interventions intended to promote public health. Public health advocates often lack effective rebuttals to these criticisms. Nanny-state accusations are largely accusations of paternalism. They conjure up emotive concern about undue governmental interference undermining peoples' autonomy. But autonomy can be understood in various ways. We outline three main conceptions of autonomy, argue that these that can underpin three different conceptions of paternalism, and consider implications for responses to nanny-state accusations and the assessment of public health interventions. Detailed conceptual analysis. The conceptions of paternalism implicit in nanny-state accusations generally depend on libertarian conceptions of autonomy. These reflect unrealistic views of personal independence and do not discriminate sufficiently between trivial and important freedoms. Decisional conceptions of paternalism, like their underlying decisional conceptions of autonomy, have limited applicability in public health contexts. Relational conceptions of paternalism incorporate relational conceptions of autonomy, so recognize that personal autonomy depends on socially shaped skills, self-identities and self-evaluations as well as externally structured opportunities. They encourage attention to the various ways that social interactions and relationships, including disrespect, stigmatization and oppression, can undermine potential for autonomy. While nanny-state accusations target any interference with negative freedom, however trivial, relational conceptions direct concerns to those infringements of negative freedom, or absences of positive freedom, serious enough to undermine self-determination, self-governance and/or self-authorization. Relational conceptions of autonomy and paternalism offer public health policymakers and practitioners a means for rebutting nanny-state accusations, and can support more nuanced and more appropriately demanding appraisals of public health interventions. Copyright © 2015 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

The effects of laboratory housing and spatial enrichment on brain size and metabolic rate in the eastern mosquitofish, Gambusia holbrooki

PubMed Central

Turschwell, Mischa P.; White, Craig R.

2016-01-01

ABSTRACT It has long been hypothesised that there is a functional correlation between brain size and metabolic rate in vertebrates. The present study tested this hypothesis in wild-caught adult mosquitofish Gambusia holbrooki by testing for an intra-specific association between resting metabolic rate (RMR) and brain size while controlling for variation in body size, and through the examination of the effects of spatial enrichment and laboratory housing on body mass-independent measures of brain size and RMR. Controlling for body mass, there was no relationship between brain size and RMR in wild-caught fish. Contrary to predictions, spatial enrichment caused a decrease in mass-independent brain size, highlighting phenotypic plasticity in the adult brain. As expected, after controlling for differences in body size, wild-caught fish had relatively larger brains than fish that had been maintained in the laboratory for a minimum of six weeks, but wild-caught fish also had significantly lower mass-independent RMR. This study demonstrates that an organisms' housing environment can cause significant plastic changes to fitness related traits including brain size and RMR. We therefore conclude that current standard laboratory housing conditions may cause captive animals to be non-representative of their wild counterparts, potentially undermining the transferability of previous laboratory-based studies of aquatic ectothermic vertebrates to wild populations. PMID:26794608

75 FR 42281 - Continuation of the National Emergency With Respect To the Former Liberian Regime of Charles Taylor

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-21

... persons, in particular their unlawful depletion of Liberian resources and their removal from Liberia and secreting of Liberian funds and property, which have undermined Liberia's transition to democracy and the... undermine Liberia's transformation and recovery. Because the actions and policies of these persons continue...

Do Treatment Manuals Undermine Youth-Therapist Alliance in Community Clinical Practice?

ERIC Educational Resources Information Center

Langer, David A.; McLeod, Bryce D.; Weisz, John R.

2011-01-01

Objective: Some critics of treatment manuals have argued that their use may undermine the quality of the client-therapist alliance. This notion was tested in the context of youth psychotherapy delivered by therapists in community clinics. Method: Seventy-six clinically referred youths (57% female, age 8-15 years, 34% Caucasian) were randomly…

3 CFR - Continuation of the National Emergency With Respect to the Actions of Certain Persons To...

Code of Federal Regulations, 2010 CFR

2010-01-01

... to the Actions of Certain Persons To Undermine the Sovereignty of Lebanon or its Democratic Processes... Sovereignty of Lebanon or its Democratic Processes and Institutions On August 1, 2007, by Executive Order... certain persons undermining the sovereignty of Lebanon or its democratic processes or institutions and...

77 FR 36111 - Continuation of the National Emergency With Respect to the Actions and Policies of Certain...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-15

... undermine Belarus democratic processes or institutions, to commit human rights abuses related to political... Belarus continued its crackdown against political opposition, civil society, and independent media. The... Government of Belarus and Other Persons To Undermine Belarus Democratic Processes or Institutions #0; #0; #0...

78 FR 36079 - Continuation of the National Emergency With Respect to the Actions and Policies of Certain...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-14

... Government of Belarus and Other Persons To Undermine Belarus's Democratic Processes or Institutions #0; #0... Government of Belarus and Other Persons To Undermine Belarus's Democratic Processes or Institutions On June... democratic processes or institutions, manifested in the fundamentally undemocratic March 2006 elections, to...

Undermining belief in false memories leads to less efficient problem-solving behaviour.

PubMed

Wang, Jianqin; Otgaar, Henry; Howe, Mark L; Smeets, Tom; Merckelbach, Harald; Nahouli, Zacharia

2017-08-01

Memories of events for which the belief in the occurrence of those events is undermined, but recollection is retained, are called nonbelieved memories (NBMs). The present experiments examined the effects of NBMs on subsequent problem-solving behaviour. In Experiment 1, we challenged participants' beliefs in their memories and examined whether NBMs affected subsequent solution rates on insight-based problems. True and false memories were elicited using the Deese/Roediger-McDermott (DRM) paradigm. Then participants' belief in true and false memories was challenged by telling them the item had not been presented. We found that when the challenge led to undermining belief in false memories, fewer problems were solved than when belief was not challenged. In Experiment 2, a similar procedure was used except that some participants solved the problems one week rather than immediately after the feedback. Again, our results showed that undermining belief in false memories resulted in lower problem solution rates. These findings suggest that for false memories, belief is an important agent in whether memories serve as effective primes for immediate and delayed problem-solving.

Response to Comment by Rabilloud on 'prevented Mortality and Greenhouse Gas Emissions from Historical and Projected Nuclear Power'

NASA Technical Reports Server (NTRS)

Kharecha, Pushker A.; Hansen, James

2013-01-01

The critique by Rabilloud-whose only listed professional affiliation is an antinuclear activist group?is grossly biased and contains numerous misleading, hyperbolic, and erroneous claims about our paper2 and about nuclear energy in general. The nature of his comments bears a striking resemblance to the fallacious reasoning commonly employed by climate change deniers to try to undermine public concern about the climate crisis. Specifically, he resorts to cherry-picking of information and diversionary (red herring) arguments, demands unrealistic exactness, and cites untrustworthy sources. None of his claims undermine any of the key results of our paper, most notably our conclusion that nuclear energy has prevented, and can continue to prevent, a very high number of fatalities and very large greenhouse gas emissions due to fossil fuel burning. It follows that, as uncomfortable as it is for many well-intentioned environmentalists to admit, efforts to undermine nuclear energy also undermine mitigation of climate change and air pollution, with a heavy cost in human lives and potentially disastrous future climate change.

Solidarity, justice and unconditional access to healthcare.

PubMed

Gheaus, Anca

2017-03-01

Luck egalitarianism provides a reason to object to conditionality in health incentive programmes in some cases when conditionality undermines political values such as solidarity or inclusiveness. This is the case with incentive programmes that aim to restrict access to essential healthcare services. Such programmes undermine solidarity. Yet, most people's lives are objectively worse, in one respect, in non-solidary societies, because solidarity contributes both instrumentally and directly to individuals' well-being. Because solidarity is non-excludable, undermining it will deprive both the prudent and the imprudent citizens of its goods. Thereby, undermining solidarity can make prudent citizens worse off than they would have otherwise been, out of no fault or choice of their own, but rather as a result of somebody else's imprudent choice. This goes against the spirit of luck egalitarianism. Therefore (luck egalitarian) justice can require us to save the imprudent and avoid conditionality in access to essential healthcare services. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Spatial variation and density-dependent dispersal in competitive coexistence.

PubMed Central

Amarasekare, Priyanga

2004-01-01

It is well known that dispersal from localities favourable to a species' growth and reproduction (sources) can prevent competitive exclusion in unfavourable localities (sinks). What is perhaps less well known is that too much emigration can undermine the viability of sources and cause regional competitive exclusion. Here, I investigate two biological mechanisms that reduce the cost of dispersal to source communities. The first involves increasing the spatial variation in the strength of competition such that sources can withstand high rates of emigration; the second involves reducing emigration from sources via density-dependent dispersal. I compare how different forms of spatial variation and modes of dispersal influence source viability, and hence source-sink coexistence, under dominance and pre-emptive competition. A key finding is that, while spatial variation substantially reduces dispersal costs under both types of competition, density-dependent dispersal does so only under dominance competition. For instance, when spatial variation in the strength of competition is high, coexistence is possible (regardless of the type of competition) even when sources experience high emigration rates; when spatial variation is low, coexistence is restricted even under low emigration rates. Under dominance competition, density-dependent dispersal has a strong effect on coexistence. For instance, when the emigration rate increases with density at an accelerating rate (Type III density-dependent dispersal), coexistence is possible even when spatial variation is quite low; when the emigration rate increases with density at a decelerating rate (Type II density-dependent dispersal), coexistence is restricted even when spatial variation is quite high. Under pre-emptive competition, density-dependent dispersal has only a marginal effect on coexistence. Thus, the diversity-reducing effects of high dispersal rates persist under pre-emptive competition even when dispersal is density dependent, but can be significantly mitigated under dominance competition if density-dependent dispersal is Type III rather than Type II. These results lead to testable predictions about source-sink coexistence under different regimes of competition, spatial variation and dispersal. They identify situations in which density-independent dispersal provides a reasonable approximation to species' dispersal patterns, and those under which consideration of density-dependent dispersal is crucial to predicting long-term coexistence. PMID:15306322

Competing infant feeding information in mothers' networks: advice that supports v. undermines clinical recommendations.

PubMed

Ashida, Sato; Lynn, Freda B; Williams, Natalie A; Schafer, Ellen J

2016-05-01

To identify the social contextual factors, specifically the presence of information that supports v. undermines clinical recommendations, associated with infant feeding behaviours among mothers in low-income areas. Cross-sectional survey evaluating social support networks and social relationships involved in providing care to the infant along with feeding beliefs and practices. Out-patient paediatric and government-funded (Women, Infants, and Children) clinics in an urban, low-income area of the south-eastern USA. Eighty-one low-income mothers of infants between 0 and 12 months old. Most mothers reported receiving both supportive and undermining advice. The presence of breast-feeding advice that supports clinical recommendations was associated with two infant feeding practices that are considered beneficial to infant health: ever breast-feeding (OR=6·7; 95% CI 1·2, 38·1) and not adding cereal in the infant's bottle (OR=15·9; 95% CI 1·1, 227·4). Advice that undermines clinical recommendations to breast-feed and advice about solid foods were not associated with these behaviours. Efforts to facilitate optimal infant feeding practices may focus on increasing information supportive of clinical recommendations while concentrating less on reducing the presence of undermining information within mothers' networks. Cultural norms around breast-feeding may be stronger than the cultural norms around the introduction of solid foods in mothers' social environments; thus, additional efforts to increase information regarding introduction of solid foods earlier in mothers' infant care career may be beneficial.

Womb Rentals and Baby-Selling: Does Surrogacy Undermine the Human Dignity and Rights of the Surrogate Mother and Child?

PubMed

Watson, Clara

2016-11-01

The question of surrogacy has dominated much of the European human rights agenda over the last two years, at the time writing, the Parliamentary Assembly of the Council of Europe hopes to adopt a resolution on surrogacy in the coming months. There is, however, danger in taking action at a supranational level to address the European 'surrogacy problem', without first honestly answering the question: does surrogacy undermine the human dignity and rights of the surrogate mother and child? This paper presents the case that surrogacy, by its nature, necessarily undermines the human dignity of both the woman and child born through such arrangements, and thus neither commercial nor altruistic surrogacy can ever be justified.

Distinctive signatures of recursion.

PubMed

Martins, Maurício Dias

2012-07-19

Although recursion has been hypothesized to be a necessary capacity for the evolution of language, the multiplicity of definitions being used has undermined the broader interpretation of empirical results. I propose that only a definition focused on representational abilities allows the prediction of specific behavioural traits that enable us to distinguish recursion from non-recursive iteration and from hierarchical embedding: only subjects able to represent recursion, i.e. to represent different hierarchical dependencies (related by parenthood) with the same set of rules, are able to generalize and produce new levels of embedding beyond those specified a priori (in the algorithm or in the input). The ability to use such representations may be advantageous in several domains: action sequencing, problem-solving, spatial navigation, social navigation and for the emergence of conventionalized communication systems. The ability to represent contiguous hierarchical levels with the same rules may lead subjects to expect unknown levels and constituents to behave similarly, and this prior knowledge may bias learning positively. Finally, a new paradigm to test for recursion is presented. Preliminary results suggest that the ability to represent recursion in the spatial domain recruits both visual and verbal resources. Implications regarding language evolution are discussed.

The chemotherapeutic agent paclitaxel selectively impairs learning while sparing source memory and spatial memory.

PubMed

Smith, Alexandra E; Slivicki, Richard A; Hohmann, Andrea G; Crystal, Jonathon D

2017-03-01

Chemotherapeutic agents are widely used to treat patients with systemic cancer. The efficacy of these therapies is undermined by their adverse side-effect profiles such as cognitive deficits that have a negative impact on the quality of life of cancer survivors. Cognitive side effects occur across a variety of domains, including memory, executive function, and processing speed. Such impairments are exacerbated under cognitive challenges and a subgroup of patients experience long-term impairments. Episodic memory in rats can be examined using a source memory task. In the current study, rats received paclitaxel, a taxane-derived chemotherapeutic agent, and learning and memory functioning was examined using the source memory task. Treatment with paclitaxel did not impair spatial and episodic memory, and paclitaxel treated rats were not more susceptible to cognitive challenges. Under conditions in which memory was not impaired, paclitaxel treatment impaired learning of new rules, documenting a decreased sensitivity to changes in experimental contingencies. These findings provide new information on the nature of cancer chemotherapy-induced cognitive impairments, particularly regarding the incongruent vulnerability of episodic memory and new learning following treatment with paclitaxel. Copyright © 2016 Elsevier B.V. All rights reserved.

Modelling heavy metals build-up on urban road surfaces for effective stormwater reuse strategy implementation.

PubMed

Hong, Nian; Zhu, Panfeng; Liu, An

2017-12-01

Urban road stormwater is an alternative water resource to mitigate water shortage issues in the worldwide. Heavy metals deposited (build-up) on urban road surface can enter road stormwater runoff, undermining stormwater reuse safety. As heavy metal build-up loads perform high variabilities in terms of spatial distribution and is strongly influenced by surrounding land uses, it is essential to develop an approach to identify hot-spots where stormwater runoff could include high heavy metal concentrations and hence cannot be reused if it is not properly treated. This study developed a robust modelling approach to estimating heavy metal build-up loads on urban roads using land use fractions (representing percentages of land uses within a given area) by an artificial neural network (ANN) model technique. Based on the modelling results, a series of heavy metal load spatial distribution maps and a comprehensive ecological risk map were generated. These maps provided a visualization platform to identify priority areas where the stormwater can be safely reused. Additionally, these maps can be utilized as an urban land use planning tool in the context of effective stormwater reuse strategy implementation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Managing the negatives of experience in physician teams.

PubMed

Hoff, Timothy

2010-01-01

Experience is a key shaper of thought and action in the health care workplace and a fundamental component of management and professional policies dealing with improving quality of care. Physicians rely on experience to structure social interaction, to determine authority relations, and to resist organizational encroachments on their work and autonomy. However, an overreliance on experience within physician teams may paradoxically undermine learning, participation, and entrepreneurship, affecting organizational performance. Approximately 100 hours of direct observation of normal workdays for physician teams (n = 17 physicians) in two different work settings in a single academic medical center located in the Northeastern part of the United States. Qualitative data were collected from physician teams in the medical intensive care unit and trauma/general surgery settings. Data were transcribed and computer analyzed through an interactive process of open coding, theoretical sampling, and pattern recognition that proceeded longitudinally. Three particular experience-based schemas were identified that physician teams used to structure social relations and perform work. These schemas involved using experience as a commodity, trump card, and liberator. Each of these schemas consisted of strongly held norms, beliefs, and values that produced team dynamics with the potential for undermining learning, participation, and entrepreneurship in the group. Organizations may move to mitigate the negative impact of an overreliance on experience among physicians by promoting bureaucratic forms of control that enable physicians to engage learning, participation, and entrepreneurship in their work while not usurping existing and difficult-to-change cultural drivers of team behavior.

How International Monetary Fund and World Bank policies undermine labor power and rights.

PubMed

Lloyd, Vincent; Weissman, Robert

2002-01-01

Based on reviews of hundreds of loan and project documents from the International Monetary Fund (IMF) and World Bank, this article provides detailed evidentiary support for critics who have long claimed that the international financial institutions require Third World countries to adopt policies that harm the interests of working people. After reviewing loan documents between the IMF and World Bank and 26 countries, the authors show that the institutions' loan conditionalities include a variety of provisions that undermine labor rights, labor power, and tens of millions of workers' standard of living. These include downsizing of the civil service and privatization of government-owned enterprises; promotion of labor flexibility: the notion that firms should be able to hire and fire workers, or change terms and conditions of work, with minimal regulatory restrictions; mandated wage rate reductions, minimum-wage reductions or containment, and spreading the wage gap between government employees and managers; and pension reforms, including privatization, that cut social security benefits. These labor-related policies take place in the context of broader IMF and World Bank structural adjustment packages that emphasize trade liberalization, with macroeconomic policies that further advance corporate interests at the expense of labor.

Sinkhole-type subsidence over abandoned coal mines in St. David, Illinois. Mine subsidence report, St. David, Illinois. A field survey and analysis of mine subsidence of abandoned coal mines in St. David, Illinois

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

Wildanger, E.G.; Mahar, J.; Nieto, A.

1980-01-01

This study examined the geologic data, mining history, and subsidence trends of the St. David region. Mine subsidence has occurred due to collapse of the abandoned mine workings. The known subsidence areas have been mapped and described. Results of the study include: (1) St. David has been undermined by both large shipping mines and smaller local mines; (2) sinkholes will continue to develop in this area in response to rock failure and roof collapse above the abandoned mine workings; (3) some primary factors that contribute to the sinkhole problems are the undermining and roof rock composition; (4) sinkholes will bemore » smaller in the future; (5) ten of the 63 sinkholes occurred close enough to structures to cause damage, and only six sinkholes caused damage; (6) ways to minimize potential damage to future homes from sinkhole subsidence are manageable; (7) threats to residents lie in the collapse of heavy walls, brick chimneys, breaks in gas, water, or electrical lines; and (8) location of future subsidence is not predictable. (DP)« less

Wide-undermining neck liposuction: tips and tricks for good results.

PubMed

Innocenti, Alessandro; Andretto Amodeo, Chiara; Ciancio, Francesco

2014-08-01

Neck rejuvenation is one of the most sought after procedures in the restoration of the facial contour. Numerous techniques to improve the aesthetic outcome and reduce downtime have been described. In our experience, wide undermining and local anesthesia are key to obtaining good results in selected patients who want a quick recovery. This article presents our experience with liposuction of the neck and proposes some tips and tricks to master wide-undermining neck liposuction. From January 2005 to September 2012, a total of 118 patients (34 males, 84 females) underwent neck liposuction. Patient selection was based mainly on age and neck-aging features. The procedure was performed with the patients under local anesthesia. A wide rhomboid-shaped skin undermining of the submandibular and neck area was performed and a very thin fat layer was preserved. Dressing was applied for 3 days. Improvement of the neck's contour was observed in all patients. Redefinition of the cervicomandibular angle and skin redraping of the cervical area occurred in all cases. No further touch-ups were needed. Edema and ecchymosis resolved in a few days. No major complications were observed. Our results show that wide-undermining neck liposuction performed under local anesthesia is an effective and safe procedure. Patient selection based on age and anatomical features was fundamental to obtain impressive improvement of neck contour. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

[Sensibility of the abdomen after high superior tension abdominoplasty].

PubMed

Castus, P; Grandjean, F-X; Tourbach, S; Heymans, O

2009-12-01

Patients who undergo an abdominoplasty frequently complain about the loss of sensibility of the abdominal wall. In this study, we analyze this sensibility after the high tension abdominoplasty. This is a prospective study of 23 females operated between July 2003 and January 2005. The abdominoplasty technique used in our study combines extensive liposuccion, limited undermining centered on the linea alba and traction sutures. The sensibilty tests are carried out preoperatively, as well as at 3 and 6 months postoperatively. The three components of the skin sensibility -tactile, algesic and thermic- are evaluated in four differents areas of the abdomen. In the lateral areas of the abdomen (liposucted only), the thermoalgesic sensibility is diminished at 3 months and completely recovers at 6 months. At 3 months postoperatively, the tactile sensibility is even better than the preoperative one and continues to improve by 6 months. The postoperative hypogastric area is widely undermined during surgery. In this area, the three types of sensibility are heavily altered at 3 months and only partially recover at 6 months. The undermining of the postoperative epigastric area is limited. In this zone, the postoperative thermoalgesic sensibility is diminished at 3 months, but completely recovers at 6 months. At 3 months, the tactile sensibility is less than the preoperative one, but it improves with time to even exceed the preoperative values at 6 months. The high tension abdominoplasty only needs a limited undermining and largely preserves the innervation of the abdominal flap. Only the hypogastric area, largely undermined, presents a sensitivity loss. These results are better than those previously reported in the literature.

Ethics in the Superintendency: The Actions of Malfeasance by a Few Superintendents Undermine the Credibility of Honest, Hard-Working Educators

ERIC Educational Resources Information Center

Pardini, Priscilla

2004-01-01

Experts suggest that moral and ethical lapses are undermining public trust in schools and their leaders--institutions and individuals long held to a higher standard of behavior than their peers in corporate and political arenas. Incidents of financial kickbacks, nepotism and conflicts of interest may grab the news media's attention. Yet…

3 CFR - Continuation of the National Emergency With Respect to Actions of Certain Persons to Undermine...

Code of Federal Regulations, 2012 CFR

2012-01-01

... 3 The President 1 2012-01-01 2012-01-01 false Continuation of the National Emergency With Respect to Actions of Certain Persons to Undermine the Sovereignty of Lebanon or Its Democratic Processes and Institutions Presidential Documents Other Presidential Documents Notice of July 28, 2011 Continuation of the National Emergency With Respect to...

Bottom-Line Mentality as an Antecedent of Social Undermining and the Moderating Roles of Core Self-Evaluations and Conscientiousness

ERIC Educational Resources Information Center

Greenbaum, Rebecca L.; Mawritz, Mary Bardes; Eissa, Gabi

2012-01-01

We propose that an employee's bottom-line mentality may have an important effect on social undermining behavior in organizations. Bottom-line mentality is defined as 1-dimensional thinking that revolves around securing bottom-line outcomes to the neglect of competing priorities. Across a series of studies, we establish an initial nomological…

Ordinary people associate addiction with loss of free will.

PubMed

Vonasch, Andrew J; Clark, Cory J; Lau, Stephan; Vohs, Kathleen D; Baumeister, Roy F

2017-06-01

It is widely believed that addiction entails a loss of free will, even though this point is controversial among scholars. There is arguably a downside to this belief, in that addicts who believe they lack the free will to quit an addiction might therefore fail to quit an addiction. A correlational study tested the relationship between belief in free will and addiction. Follow-up studies tested steps of a potential mechanism: 1) people think drugs undermine free will 2) people believe addiction undermines free will more when doing so serves the self 3) disbelief in free will leads people to perceive various temptations as more addictive. People with lower belief in free will were more likely to have a history of addiction to alcohol and other drugs, and also less likely to have successfully quit alcohol. People believe that drugs undermine free will, and they use this belief to self-servingly attribute less free will to their bad actions than to good ones. Low belief in free will also increases perceptions that things are addictive. Addiction is widely seen as loss of free will. The belief can be used in self-serving ways that may undermine people's efforts to quit.

When do financial incentives reduce intrinsic motivation? comparing behaviors studied in psychological and economic literatures.

PubMed

Promberger, Marianne; Marteau, Theresa M

2013-09-01

To review existing evidence on the potential of incentives to undermine or "crowd out" intrinsic motivation, in order to establish whether and when it predicts financial incentives to crowd out motivation for health-related behaviors. We conducted a conceptual analysis to compare definitions and operationalizations of the effect, and reviewed existing evidence to identify potential moderators of the effect. In the psychological literature, we find strong evidence for an undermining effect of tangible rewards on intrinsic motivation for simple tasks when motivation manifest in behavior is initially high. In the economic literature, evidence for undermining effects exists for a broader variety of behaviors, in settings that involve a conflict of interest between parties. By contrast, for health related behaviors, baseline levels of incentivized behaviors are usually low, and only a subset involve an interpersonal conflict of interest. Correspondingly, we find no evidence for crowding out of incentivized health behaviors. The existing evidence does not warrant a priori predictions that an undermining effect would be found for health-related behaviors. Health-related behaviors and incentives schemes differ greatly in moderating characteristics, which should be the focus of future research. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Simple Skin-Stretching Device in Assisted Tension-Free Wound Closure.

PubMed

Cheng, Li-Fu; Lee, Jiunn-Tat; Hsu, Honda; Wu, Meng-Si

2017-03-01

Numerous conventional wound reconstruction methods, such as wound undermining with direct suture, skin graft, and flap surgery, can be used to treat large wounds. The adequate undermining of the skin flaps of a wound is a commonly used technique for achieving the closure of large tension wounds; however, the use of tension to approximate and suture the skin flaps can cause ischemic marginal necrosis. The purpose of this study is to use elastic rubber bands to relieve the tension of direct wound closure for simultaneously minimizing the risks of wound dehiscence and wound edge ischemia that lead to necrosis. This retrospective study was conducted to evaluate our clinical experiences with 22 large wounds, which involved performing primary closures under a considerable amount of tension by using elastic rubber bands in a skin-stretching technique after a wide undermining procedure. Assessment of the results entailed complete wound healing and related complications. All 22 wounds in our study showed fair to good results except for one. The mean success rate was approximately 95.45%. The simple skin-stretching design enabled tension-free skin closure, which pulled the bilateral undermining skin flaps as bilateral fasciocutaneous advancement flaps. The skin-stretching technique was generally successful.

Histological case-control study of peeling-induced skin changes by different peeling agents in surgically subcutaneous undermined skin flaps in facelift patients.

PubMed

Gonser, P; Kaestner, S; Jaminet, P; Kaye, K

2017-11-01

A histological evaluation of peeling-induced skin changes in subcutaneous undermined preauricular facial skin flaps of nine patients was performed. There were three treatment groups: Trichloroacetic acid (TCA) 25%, TCA 40% and phenol/croton oil; one group served as control. Two independent evaluators determined the epidermal and dermal thickness and the depth of necrosis (micrometre). The percentual tissue damage due to the peeling was calculated, and a one-sample t-test for statistical significance was performed. On the basis of the histomorphological changes, peeling depth was classified as superficial, superficial-partial, deep-partial and full thickness chemical burn. The histological results revealed a progression of wound depth for different peeling agents without full thickness necrosis. TCA peels of up to 40% can be safely applied on subcutaneous undermined facial skin flaps without impairing the vascular patency, producing a predictable chemical burn, whereas deep peels such as phenol/croton oil peels should not be applied on subcutaneous undermined skin so as to not produce skin slough or necrosis by impairing vascular patency. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

When Do Financial Incentives Reduce Intrinsic Motivation? Comparing Behaviors Studied in Psychological and Economic Literatures

PubMed Central

2013-01-01

Objective: To review existing evidence on the potential of incentives to undermine or “crowd out” intrinsic motivation, in order to establish whether and when it predicts financial incentives to crowd out motivation for health-related behaviors. Method: We conducted a conceptual analysis to compare definitions and operationalizations of the effect, and reviewed existing evidence to identify potential moderators of the effect. Results: In the psychological literature, we find strong evidence for an undermining effect of tangible rewards on intrinsic motivation for simple tasks when motivation manifest in behavior is initially high. In the economic literature, evidence for undermining effects exists for a broader variety of behaviors, in settings that involve a conflict of interest between parties. By contrast, for health related behaviors, baseline levels of incentivized behaviors are usually low, and only a subset involve an interpersonal conflict of interest. Correspondingly, we find no evidence for crowding out of incentivized health behaviors. Conclusion: The existing evidence does not warrant a priori predictions that an undermining effect would be found for health-related behaviors. Health-related behaviors and incentives schemes differ greatly in moderating characteristics, which should be the focus of future research. PMID:24001245

Inattentive listening undermines self-verification in personal storytelling.

PubMed

Pasupathi, Monisha; Rich, Ben

2005-08-01

Two studies explore the narrative construction of self-perceptions in conversational storytelling among pairs of same-sex friends. Specifically, the studies examined how listener behavior can support or undermine attempts to self-verify in personal storytelling. In two studies (n=100 dyads), speakers told attentive, distracted, or disagreeable (Study 1 only) friends about a recent experience. Distracted, but not disagreeable, friends tended to undermine participants' attempts to verify their self-perception of being interested in an activity (Study 1) or their self-perception that an event was typical for them (Study 2). These results support the notion that friends can be an important source of influence on self-perceptions and, perhaps surprisingly, suggest that responsiveness from friends, rather than agreement per se, may be crucial for supporting self-verification processes.

Evidence for the negative impact of reward on self-regulated learning.

PubMed

Wehe, Hillary S; Rhodes, Matthew G; Seger, Carol A

2015-01-01

The undermining effect refers to the detrimental impact rewards can have on intrinsic motivation to engage in a behaviour. The current study tested the hypothesis that participants' self-regulated learning behaviours are susceptible to the undermining effect. Participants were assigned to learn a set of Swahili-English word pairs. Half of the participants were offered a reward for performance, and half were not offered a reward. After the initial study phase, participants were permitted to continue studying the words during a free period. The results were consistent with an undermining effect: Participants who were not offered a reward spent more time studying the words during the free period. The results suggest that rewards may negatively impact self-regulated learning behaviours and provide support for the encouragement of intrinsic motivation.

Introduction: Institutional corruption and the pharmaceutical policy.

PubMed

Rodwin, Marc A

2013-01-01

Today, the goals of pharmaceutical policy and medical practice are often undermined due to institutional corruption - that is, widespread or systemic practices, usually legal, that undermine an institution's objectives or integrity. In this symposium, 16 articles investigate the corruption of pharmaceutical policy, each taking a different look at the sources of corruption, how it occurs, and what is corrupted. We will see that the pharmaceutical industry's own purposes are often undermined. Furthermore, pharmaceutical industry funding of election campaigns and lobbying skews the legislative process that sets pharmaceutical policy. Moreover, certain practices have corrupted medical research, the production of medical knowledge, the practice of medicine, drug safety, the Food and Drug Administration's oversight of the pharmaceutical market, and the trustworthiness of patient advocacy organizations. © 2013 American Society of Law, Medicine & Ethics, Inc.

'Mum never loved me.' How structural factors influence adolescent sexual and reproductive health through parent-child connectedness: a qualitative study in rural Tanzania.

PubMed

Wamoyi, Joyce; Wight, Daniel

2014-01-01

Research in high income countries shows parent-child connectedness to be protective against undesirable sexual and reproductive health (SRH) outcomes among young people. Little has been done to understand the nature of parent-child connectedness, the structural factors that impact on connectedness and parents' understanding of how connectedness affects their children's sexual behaviour in sub-Saharan Africa and Tanzania in particular. Ethnographic research involved 30 days of observation in 10 households, 9 focus group discussions and 60 in-depth interviews. Thematic analysis was conducted using NVIVO qualitative data analysis software. The structural factors with greatest influence on connectedness were economic circumstances, gender, social status, state education, and globalisation. Economic circumstances impacted on parent-child connectedness through parents' ability to provide for their children's material needs, and the time their occupation allowed for them to spend with their children and monitor their activities. Appropriate parent-child interactions were shaped by gender norms and by social status in the form of respectability, adolescents' adherence to norms of respect/obedience shaping their parents' affection. State education affected parents' preferences between children but also undermined parental authority, as did broader globalisation. Connectedness was related to SRH in a bi-directional way: lack of connectedness was linked to young people's low self-esteem and risky sexual behaviour while unplanned pregnancies seriously undermined young women's connectedness with their parents. Since material provision was perceived to be a central element of parent-child connectedness, structural factors limiting provision made transactional sex more likely both through direct material pathways and emotional ones. Motives for transactional sex were said to be material needs and to feel loved and cared for. An important pathway by which structural factors shape adolescent SRH outcomes is through parent-child connectedness, especially parents' ability to spend time with their children and provide for their economic needs. Modifying these structural factors should facilitate parent-child connectedness, which may help delay early sexual intercourse, protect young people against unplanned pregnancy through encouraging communication on contraception use and, overall, promote healthy adolescent development.

Distribution and predictors of wing shape and size variability in three sister species of solitary bees

PubMed Central

Prunier, Jérôme G.; Dewulf, Alexandre; Kuhlmann, Michael; Michez, Denis

2017-01-01

Morphological traits can be highly variable over time in a particular geographical area. Different selective pressures shape those traits, which is crucial in evolutionary biology. Among these traits, insect wing morphometry has already been widely used to describe phenotypic variability at the inter-specific level. On the contrary, fewer studies have focused on intra-specific wing morphometric variability. Yet, such investigations are relevant to study potential convergences of variation that could highlight micro-evolutionary processes. The recent sampling and sequencing of three solitary bees of the genus Melitta across their entire species range provides an excellent opportunity to jointly analyse genetic and morphometric variability. In the present study, we first aim to analyse the spatial distribution of the wing shape and centroid size (used as a proxy for body size) variability. Secondly, we aim to test different potential predictors of this variability at both the intra- and inter-population levels, which includes genetic variability, but also geographic locations and distances, elevation, annual mean temperature and precipitation. The comparison of spatial distribution of intra-population morphometric diversity does not reveal any convergent pattern between species, thus undermining the assumption of a potential local and selective adaptation at the population level. Regarding intra-specific wing shape differentiation, our results reveal that some tested predictors, such as geographic and genetic distances, are associated with a significant correlation for some species. However, none of these predictors are systematically identified for the three species as an important factor that could explain the intra-specific morphometric variability. As a conclusion, for the three solitary bee species and at the scale of this study, our results clearly tend to discard the assumption of the existence of a common pattern of intra-specific signal/structure within the intra-specific wing shape and body size variability. PMID:28273178

Integrating spatial and numerical structure in mathematical patterning

NASA Astrophysics Data System (ADS)

Ni’mah, K.; Purwanto; Irawan, E. B.; Hidayanto, E.

2018-03-01

This paper reports a study monitoring the integrating spatial and numerical structure in mathematical patterning skills of 30 students grade 7th of junior high school. The purpose of this research is to clarify the processes by which learners construct new knowledge in mathematical patterning. Findings indicate that: (1) students are unable to organize the structure of spatial and numerical, (2) students were only able to organize the spatial structure, but the numerical structure is still incorrect, (3) students were only able to organize numerical structure, but its spatial structure is still incorrect, (4) students were able to organize both of the spatial and numerical structure.

(Where) Is Functional Decline Isolating? Disordered Environments and the Onset of Disability.

PubMed

Schafer, Markus H

2018-03-01

The onset of disability is believed to undermine social connectedness and raise the risk of social isolation, yet spatial environments are seldom considered in this process. This study examines whether unruly home and neighborhood conditions intensify the association between disability onset and several dimensions of social connectedness. I incorporate longitudinal data from the National Social Life, Health, and Aging Project, which contains environmental evaluations conducted by trained observers ( N = 1,558). Results from Poisson, ordinal logistic, and linear regression models reveal heterogeneous consequences of disablement: disability onset was associated with reduced core network size, fewer friends, lower likelihood of social interaction, and less overall social connectedness-though mainly when accompanied by higher levels of household disorder. There was limited evidence that neighborhood disorder moderated consequences of disability. Findings point to the importance of the home as an environmental resource and underscore important contextual contingencies in the isolating consequences of disability.

Promoting social welfare through oral health: New Jersey's fluoridation experience.

PubMed

Mendoza, Roger Lee

2009-01-01

This study examines the contentious public health policy of treating community water with fluoride in the United States. The question for scholarly investigation is why water fluoridation has been unsuccessful in several parts of the United States relative to the rest. It addresses this question by looking into the processes of scientific discovery and information dissemination, benefits and risks of science-based health policy, related issues of provision and production, and spatial dimensions of policy development. The case method based on New Jersey's experience in public water fluoridation, was opted for this study. We find that policy debates, which are confined to single key issues, tend to breed binary choices and bipolar debates and result in policy stalemates. Consumer accessibility and desirability of merit goods thus become sharply conflicting social welfare values. They undermine the intent of science-based policies and often make alternative and second-best policies more practical to adopt.

Global meta-analysis reveals low consistency of biodiversity congruence relationships.

PubMed

Westgate, Martin J; Barton, Philip S; Lane, Peter W; Lindenmayer, David B

2014-05-21

Knowledge of the number and distribution of species is fundamental to biodiversity conservation efforts, but this information is lacking for the majority of species on earth. Consequently, subsets of taxa are often used as proxies for biodiversity; but this assumes that different taxa display congruent distribution patterns. Here we use a global meta-analysis to show that studies of cross-taxon congruence rarely give consistent results. Instead, species richness congruence is highest at extreme spatial scales and close to the equator, while congruence in species composition is highest at large extents and grain sizes. Studies display highest variance in cross-taxon congruence when conducted in areas with dissimilar areal extents (for species richness) or latitudes (for species composition). These results undermine the assumption that a subset of taxa can be representative of biodiversity. Therefore, researchers whose goal is to prioritize locations or actions for conservation should use data from a range of taxa.

Exploration and exploitation in the macrohistory of the pre-Hispanic Pueblo Southwest

PubMed Central

Bocinsky, R. Kyle; Rush, Johnathan; Kintigh, Keith W.; Kohler, Timothy A.

2016-01-01

Cycles of demographic and organizational change are well documented in Neolithic societies, but the social and ecological processes underlying them are debated. Such periodicities are implicit in the “Pecos classification,” a chronology for the pre-Hispanic U.S. Southwest introduced in Science in 1927 which is still widely used. To understand these periodicities, we analyzed 29,311 archaeological tree-ring dates from A.D. 500 to 1400 in the context of a novel high spatial resolution, annual reconstruction of the maize dry-farming niche for this same period. We argue that each of the Pecos periods initially incorporates an “exploration” phase, followed by a phase of “exploitation” of niches that are simultaneously ecological, cultural, and organizational. Exploitation phases characterized by demographic expansion and aggregation ended with climatically driven downturns in agricultural favorability, undermining important bases for social consensus. Exploration phases were times of socio-ecological niche discovery and development. PMID:27051879

PA014-- Deception and Doubt --Strategies for Undermining and Supporting Global Climate Science--PA014

NASA Astrophysics Data System (ADS)

Nelson, C.

2012-12-01

DECEPTION AND DOUBT--STRATEGIES FOR UNDERMINING AND SUPPORTING GLOBAL CLIMATE SCIENCE--PA014 The fundamental strategy for undermining confidence in the now substantial scientific consensus about global warming is to sow doubt about the degree of consensus. Rather than mount an obvious anti-science stance, commercial interests seek to champion science, arguing for better science, more complete and definitive science. This strategy has a sixty-year history, beginning with the tobacco industry in the 1950s and proceeding through the chemical, energy, paint, and other industries. Thousands of faculty members have quietly sold themselves as public spokespersons or confidential consultants to industry in the service of this strategy. A multipart program--involving educating people about this history and exposing faculty collaboration--may help free climate science from those who aim to distort its conclusions.

INSAR For Early Warning Of Possible Highway Instability Over Undermined Area Of Ostrava

NASA Astrophysics Data System (ADS)

Lazecky, Milan; Kacmarik, Michal; Rapant, Petr

2012-01-01

A part of czech highway D1 connecting Ostrava with Prague and Poland, is built over an undermined area of Ostrava-Svinov. Since the end of 2010, this part of the highway is fully operational. Because of undermining, a subsidence can be expected, however with a very slow rate since the mines are no more active in this area. Several TerraSAR-X images from 2011 are investigated interferometrically in order to estimate a precise deformation model. Subjects of interest are movements of newly built highway bridges, banks and close neighbourhood. Existing C-band multitemporal InSAR processing results of ERS and Envisat are available from an earlier period that reveil a slow trend of residual subsidence. In this project, InSAR will be investigated as a tool for an early warning for highway stability.

Attempts to undermine tobacco control: tobacco industry "youth smoking prevention" programs to undermine meaningful tobacco control in Latin America.

PubMed

Sebrié, Ernesto M; Glantz, Stanton A

2007-08-01

We sought to understand how the tobacco industry uses "youth smoking prevention" programs in Latin America. We analyzed tobacco industry documents, so-called "social reports," media reports, and material provided by Latin American public health advocates. Since the early 1990s, multinational tobacco companies have promoted "youth smoking prevention" programs as part of their "Corporate Social Responsibility" campaigns. The companies also partnered with third-party allies in Latin America, most notably nonprofit educational organizations and education and health ministries. Even though there is no evidence that these programs reduce smoking among youths, they have met the industry's goal of portraying the companies as concerned corporate citizens and undermining effective tobacco control interventions that are required by the World Health Organization Framework Convention on Tobacco Control.

Modeling Reef Fish Biomass, Recovery Potential, and Management Priorities in the Western Indian Ocean.

PubMed

McClanahan, Timothy R; Maina, Joseph M; Graham, Nicholas A J; Jones, Kendall R

2016-01-01

Fish biomass is a primary driver of coral reef ecosystem services and has high sensitivity to human disturbances, particularly fishing. Estimates of fish biomass, their spatial distribution, and recovery potential are important for evaluating reef status and crucial for setting management targets. Here we modeled fish biomass estimates across all reefs of the western Indian Ocean using key variables that predicted the empirical data collected from 337 sites. These variables were used to create biomass and recovery time maps to prioritize spatially explicit conservation actions. The resultant fish biomass map showed high variability ranging from ~15 to 2900 kg/ha, primarily driven by human populations, distance to markets, and fisheries management restrictions. Lastly, we assembled data based on the age of fisheries closures and showed that biomass takes ~ 25 years to recover to typical equilibrium values of ~1200 kg/ha. The recovery times to biomass levels for sustainable fishing yields, maximum diversity, and ecosystem stability or conservation targets once fishing is suspended was modeled to estimate temporal costs of restrictions. The mean time to recovery for the whole region to the conservation target was 8.1(± 3SD) years, while recovery to sustainable fishing thresholds was between 0.5 and 4 years, but with high spatial variation. Recovery prioritization scenario models included one where local governance prioritized recovery of degraded reefs and two that prioritized minimizing recovery time, where countries either operated independently or collaborated. The regional collaboration scenario selected remote areas for conservation with uneven national responsibilities and spatial coverage, which could undermine collaboration. There is the potential to achieve sustainable fisheries within a decade by promoting these pathways according to their social-ecological suitability.

Modeling Reef Fish Biomass, Recovery Potential, and Management Priorities in the Western Indian Ocean

PubMed Central

McClanahan, Timothy R.; Maina, Joseph M.; Graham, Nicholas A. J.; Jones, Kendall R.

2016-01-01

Fish biomass is a primary driver of coral reef ecosystem services and has high sensitivity to human disturbances, particularly fishing. Estimates of fish biomass, their spatial distribution, and recovery potential are important for evaluating reef status and crucial for setting management targets. Here we modeled fish biomass estimates across all reefs of the western Indian Ocean using key variables that predicted the empirical data collected from 337 sites. These variables were used to create biomass and recovery time maps to prioritize spatially explicit conservation actions. The resultant fish biomass map showed high variability ranging from ~15 to 2900 kg/ha, primarily driven by human populations, distance to markets, and fisheries management restrictions. Lastly, we assembled data based on the age of fisheries closures and showed that biomass takes ~ 25 years to recover to typical equilibrium values of ~1200 kg/ha. The recovery times to biomass levels for sustainable fishing yields, maximum diversity, and ecosystem stability or conservation targets once fishing is suspended was modeled to estimate temporal costs of restrictions. The mean time to recovery for the whole region to the conservation target was 8.1(± 3SD) years, while recovery to sustainable fishing thresholds was between 0.5 and 4 years, but with high spatial variation. Recovery prioritization scenario models included one where local governance prioritized recovery of degraded reefs and two that prioritized minimizing recovery time, where countries either operated independently or collaborated. The regional collaboration scenario selected remote areas for conservation with uneven national responsibilities and spatial coverage, which could undermine collaboration. There is the potential to achieve sustainable fisheries within a decade by promoting these pathways according to their social-ecological suitability. PMID:27149673

A systemic approach to occupational and environmental health.

PubMed

Spitzer, Skip

2005-01-01

As the corporate role in occupational and public health receives increased scrutiny, it is essential to recognize that it is not sufficient to identify specific acts of malfeasance or influence, or even to campaign to address them. A more comprehensive and systemic framework for understanding the role of corporations requires consideration of corporate power and its effects as endemic features of national socioeconomic systems and the rapidly integrating global order. The underlying social structures that produce social and environmental problems, and undermine reform, make systemic change necessary. Identifying this "structure of harm" provides important implications for researchers, policymakers, activists, and others trying to address environmental and social problems, particularly with regard to integrating efforts to address immediate impacts with those for longer-term, systemic change.

Does Grading Undermine Feedback? the Influence of Grades on the Effectiveness of Corrective Feedback on L2 Writing

ERIC Educational Resources Information Center

Dlaska, Andrea; Krekeler, Christian

2017-01-01

It has been questioned whether students notice, act upon and, ultimately, learn from feedback if feedback about a task is received in conjunction with grades. If grades undermine feedback, it could be argued that it is a waste of teachers' time to add comments to students' written work if the students also receive grades. With reference to SLA…

What if Reading is Easy but Unimportant? How Students’ Patterns of Affirming and Undermining Motivation for Reading Information Texts Predict Different Reading Outcomes

PubMed Central

Rosenzweig, Emily Q.; Wigfield, Allan

2016-01-01

Many affirming and undermining motivational constructs affect students as they read information texts, but few researchers have explored how these motivations are patterned within students. In this study we used cluster analysis to classify middle school students (n = 1,134) based on their patterns of self-efficacy, perceived difficulty, value, and devalue for reading school information texts. We then compared how the patterns predicted students’ language arts grades, science information text comprehension, and dedication to reading school information texts. We found and validated a four-cluster solution. One cluster included a pattern of high affirming and low undermining motivations, and another included low affirming and high undermining motivations. Students with these patterns earned the highest and lowest scores, respectively, on all outcomes. A third pattern showed high self-efficacy/low difficulty with low value/high devalue, and a fourth showed moderate levels of all four motivational constructs. Students with the high efficacy and devalue pattern showed high information text comprehension but relatively low dedication. Students with the moderate pattern showed high dedication but low initial information text comprehension. Students with these two patterns earned similar grades. We discuss the implications of our findings for motivation theories and for school instruction that involves information text reading. PMID:28496289

The Ethics of Vaccination Nudges in Pediatric Practice.

PubMed

Navin, Mark C

2017-03-01

Techniques from behavioral economics-nudges-may help physicians increase pediatric vaccine compliance, but critics have objected that nudges can undermine autonomy. Since autonomy is a centrally important value in healthcare decision-making contexts, it counts against pediatric vaccination nudges if they undermine parental autonomy. Advocates for healthcare nudges have resisted the charge that nudges undermine autonomy, and the recent bioethics literature illustrates the current intractability of this debate. This article rejects a principle to which parties on both sides of this debate sometimes seem committed: that nudges are morally permissible only if they are consistent with autonomy. Instead, I argue that, at least in the case of pediatric vaccination, some autonomy-undermining nudges may be morally justified. This is because parental autonomy in pediatric decision-making is not as morally valuable as the autonomy of adult patients, and because the interests of both the vaccinated child and other members of the community can sometimes be weighty enough to justify autonomy-infringing pediatric vaccination nudges. This article concludes with a set of worries about the effect of pediatric vaccination nudges on parent-physician relationships, and it calls on the American Academy of Pediatrics to draw on scientific and bioethics research to develop guidelines for the use of nudges in pediatric practice and, in particular, for the use of pediatric vaccination nudges.

Simple skin-stretching device in assisted tension-free wound closure

PubMed Central

Cheng, Li-Fu; Lee, Jiunn-Tat; Hsu, Honda; Wu, Meng-Si

2017-01-01

Background Numerous conventional wound reconstruction methods such as wound undermining with direct suture, skin graft, and flap surgery can be used to treat large wounds. The adequate undermining of the skin flaps of a wound is a commonly used technique for achieving the closure of large tension wounds; however, the use of tension to approximate and suture the skin flaps can cause ischemic marginal necrosis. The purpose of this study is to use elastic rubber bands to relieve the tension of direct wound closure for simultaneously minimizing the risks of wound dehiscence and wound edge ischemia that lead to necrosis. Materials and Methods This retrospective study was conducted to evaluate our clinical experiences with 22 large wounds, which involved performing primary closures under a considerable amount of tension by using elastic rubber bands in a skin-stretching technique following a wide undermining procedure. Assessment of the results entailed complete wound healing and related complications. Results All 22 wounds in our study showed fair to good results except for one. The mean success rate was approximately 95.45%. Conclusion The simple skin-stretching design enabled tension-free skin closure, which pulled the bilateral undermining skin flaps as bilateral fasciocutaneous advancement flaps. The skin-stretching technique was generally successful. PMID:28195891

What if Reading is Easy but Unimportant? How Students' Patterns of Affirming and Undermining Motivation for Reading Information Texts Predict Different Reading Outcomes.

PubMed

Rosenzweig, Emily Q; Wigfield, Allan

2017-01-01

Many affirming and undermining motivational constructs affect students as they read information texts, but few researchers have explored how these motivations are patterned within students. In this study we used cluster analysis to classify middle school students (n = 1,134) based on their patterns of self-efficacy, perceived difficulty, value, and devalue for reading school information texts. We then compared how the patterns predicted students' language arts grades, science information text comprehension, and dedication to reading school information texts. We found and validated a four-cluster solution. One cluster included a pattern of high affirming and low undermining motivations, and another included low affirming and high undermining motivations. Students with these patterns earned the highest and lowest scores, respectively, on all outcomes. A third pattern showed high self-efficacy/low difficulty with low value/high devalue, and a fourth showed moderate levels of all four motivational constructs. Students with the high efficacy and devalue pattern showed high information text comprehension but relatively low dedication. Students with the moderate pattern showed high dedication but low initial information text comprehension. Students with these two patterns earned similar grades. We discuss the implications of our findings for motivation theories and for school instruction that involves information text reading.

What undermines healthy habits with regard to physical activity and food? Voices of adolescents in a disadvantaged community.

PubMed

Jonsson, Linus; Larsson, Christel; Berg, Christina; Korp, Peter; Lindgren, Eva-Carin

2017-12-01

This study aimed to illuminate factors that undermine the healthy habits of adolescents from a multicultural community with low socioeconomic status (S.E.S.) in Sweden with regard to physical activity (P.A.) and food, as stated in their own voices. Adolescents (n = 53, 12-13 y/o) were recruited from one school situated in a multicultural community characterized by low S.E.S. Embracing an interpretive approach, 10 focus-group interviews were conducted to produce data for the study. The focus-group interviews were audio recorded, transcribed verbatim, and analysed using qualitative content analysis. The analysis resulted in two major themes: (1) the availability of temptations is large, and support from the surroundings is limited; and (2) norms and demands set the agenda. The adolescents' voices illuminate a profound awareness and the magnitude of tempting screen-based activities as undermining their P.A. and healthy food habits. Moreover, several gender boundaries were highlighted as undermining girls' P.A. and healthy food habits. The adolescents' stories illuminated that it is difficult for them, within their environment, to establish healthy habits with regard to P.A. and food. To facilitate the adolescents' healthy habits, we suggest that support from family, friends, the school, and society at large is essential.

Hospital capacity and management preparedness for pandemic influenza in Victoria.

PubMed

Dewar, Ben; Barr, Ian; Robinson, Priscilla

2014-04-01

This study was designed to investigate acute hospital pandemic influenza preparedness in Victoria, Australia, particularly focussing on planning and management efforts. A prospective study was conducted by questionnaire and semi-structured interview of health managers across the Victorian hospital system from July to October 2011. Participants with responsibility for emergency management, planning and operations were selected from every hospital in Victoria with an emergency department to complete a questionnaire (response rate 22/43 = 51%). Each respondent was invited to participate in a phone-based semi-structured interview (response rate 11/22 = 50%). Rural/regional hospitals demonstrated higher levels of clinical (86%) and non-clinical (86%) staff contingency planning than metropolitan hospitals (60% and 40% respectively). Pandemic plans were not being sufficiently tested in exercises or drills, which is likely to undermine their effectiveness. All respondents reported hand hygiene and standard precautions programs in place, although only one-third (33%) of metropolitan respondents and no rural/regional respondents reported being able to meet patient needs with high levels of staff absenteeism. Almost half Victoria's healthcare workers were unvaccinated against influenza. Hospitals across Victoria demonstrated different levels of influenza pandemic preparedness and planning. If a more severe influenza pandemic than that of 2009 arose, Victorian hospitals would struggle with workforce and infrastructure problems, particularly in rural/regional areas. Staff absenteeism threatens to undermine hospital pandemic responses. Various strategies, including education and communication, should be included with in-service training to provide staff with confidence in their ability to work safely during a future pandemic. © 2014 The Authors. ANZJPH © 2014 Public Health Association of Australia.

Impact of solvent granularity and layering on tracer hydrodynamics in confinement.

PubMed

Bollinger, Jonathan A; Carmer, James; Jain, Avni; Truskett, Thomas M

2016-11-28

Classic hydrodynamic arguments establish that when a spherical tracer particle is suspended between parallel walls, tracer-wall coupling mediated by the solvent will cause the tracer to exhibit position-dependent diffusivity. We investigate how the diffusivity profiles of confined tracers are impacted by the diameter size-ratio of the tracer to solvent: starting from the classic limit of infinite size-ratio (i.e., continuum solvent), we consider size-ratios of four or less to examine how hydrodynamic predictions are disrupted for systems where the tracer and solvent are of similar scale. We use computer simulations and techniques based on the Fokker-Planck formalism to calculate the diffusivity profiles of hard-sphere tracer particles in hard-sphere solvents, focusing on the dynamics perpendicular to the walls. Given wall separations of several tracer diameters, we first consider confinement between hard walls, where anisotropic structuring at the solvent lengthscale generates inhomogeneity in the tracer free-energy landscape and undermines hydrodynamic predictions locally. We then introduce confining planes that we term transparent walls, which restrict tracer and solvent center-accessibilities while completely eliminating static anisotropy, and reveal position-dependent signatures in tracer diffusivity solely attributable to confinement. With or without suppressing static heterogeneity, we find that tracer diffusivity increasingly deviates on a local basis from hydrodynamic predictions at smaller size-ratios. However, hydrodynamic theory still approximately captures spatially-averaged dynamics across the pores even for very small tracer-solvent size-ratios over a wide range of solvent densities and wall separations.

The Relative Importance of Spatial Versus Temporal Structure in the Perception of Biological Motion: An Event-Related Potential Study

ERIC Educational Resources Information Center

Hirai, Masahiro; Hiraki, Kazuo

2006-01-01

We investigated how the spatiotemporal structure of animations of biological motion (BM) affects brain activity. We measured event-related potentials (ERPs) during the perception of BM under four conditions: normal spatial and temporal structure; scrambled spatial and normal temporal structure; normal spatial and scrambled temporal structure; and…

Self-Uncertainty and the Influence of Alternative Goals on Self-Regulation.

PubMed

Light, Alysson E; Rios, Kimberly; DeMarree, Kenneth G

2018-01-01

The current research examines factors that facilitate or undermine goal pursuit. Past research indicates that attempts to reduce self-uncertainty can result in increased goal motivation. We explore a critical boundary condition of this effect-the presence of alternative goals. Though self-regulatory processes usually keep interest in alternative goals in check, uncertainty reduction may undermine these self-regulatory efforts by (a) reducing conflict monitoring and (b) increasing valuation of alternative goals. As such, reminders of alternative goals will draw effort away from focal goals for self-uncertain (but not self-certain) participants. Across four studies and eight supplemental studies, using different focal goals (e.g., academic achievement, healthy eating) and alternative goals (e.g., social/emotional goals, attractiveness, indulgence), we found that alternative goal salience does not negatively influence goal-directed behavior among participants primed with self-certainty, but that reminders of alternative goals undermine goal pursuit among participants primed with self-uncertainty.

Are Emotions Transmitted From Work to Family? A Crossover Model of Psychological Contract Breach.

PubMed

Liang, Huai-Liang

2018-01-01

Based on affective events theory and the crossover model, this study examines the effect of psychological contract breach on employee dysfunctional behavior and partner family undermining and explores the crossover effect of employee dysfunctional behavior on partner family undermining in work-family issues. This study collected 370 employee-partner dyads (277 male employees, 93 female employees, M age = 43.59 years) from a large manufacturing organization. The results of this study support the conception that employees' psychological contract breach results in frustration in the workplace. In addition, mediation analysis results reveal that psychological contract breach relates to employee dysfunctional behavior in the workplace. The findings show that partners' psychological strain mediates the relationship between employee dysfunctional behavior and partner family undermining. Furthermore, these findings provide investigations for the crossover model to display the value of psychological contract breach in family issues.

The Collective Benefits of Feeling Good and Letting Go: Positive Emotion and (dis)Inhibition Interact to Predict Cooperative Behavior

PubMed Central

Rand, David G.; Kraft-Todd, Gordon; Gruber, June

2015-01-01

Cooperation is central to human existence, forming the bedrock of everyday social relationships and larger societal structures. Thus, understanding the psychological underpinnings of cooperation is of both scientific and practical importance. Recent work using a dual-process framework suggests that intuitive processing can promote cooperation while deliberative processing can undermine it. Here we add to this line of research by more specifically identifying deliberative and intuitive processes that affect cooperation. To do so, we applied automated text analysis using the Linguistic Inquiry and Word Count (LIWC) software to investigate the association between behavior in one-shot anonymous economic cooperation games and the presence inhibition (a deliberative process) and positive emotion (an intuitive process) in free-response narratives written after (Study 1, N = 4,218) or during (Study 2, N = 236) the decision-making process. Consistent with previous results, across both studies inhibition predicted reduced cooperation while positive emotion predicted increased cooperation (even when controlling for negative emotion). Importantly, there was a significant interaction between positive emotion and inhibition, such that the most cooperative individuals had high positive emotion and low inhibition. This suggests that inhibition (i.e., reflective or deliberative processing) may undermine cooperative behavior by suppressing the prosocial effects of positive emotion. PMID:25625722

The collective benefits of feeling good and letting go: positive emotion and (dis)inhibition interact to predict cooperative behavior.

PubMed

Rand, David G; Kraft-Todd, Gordon; Gruber, June

2015-01-01

Cooperation is central to human existence, forming the bedrock of everyday social relationships and larger societal structures. Thus, understanding the psychological underpinnings of cooperation is of both scientific and practical importance. Recent work using a dual-process framework suggests that intuitive processing can promote cooperation while deliberative processing can undermine it. Here we add to this line of research by more specifically identifying deliberative and intuitive processes that affect cooperation. To do so, we applied automated text analysis using the Linguistic Inquiry and Word Count (LIWC) software to investigate the association between behavior in one-shot anonymous economic cooperation games and the presence inhibition (a deliberative process) and positive emotion (an intuitive process) in free-response narratives written after (Study 1, N = 4,218) or during (Study 2, N = 236) the decision-making process. Consistent with previous results, across both studies inhibition predicted reduced cooperation while positive emotion predicted increased cooperation (even when controlling for negative emotion). Importantly, there was a significant interaction between positive emotion and inhibition, such that the most cooperative individuals had high positive emotion and low inhibition. This suggests that inhibition (i.e., reflective or deliberative processing) may undermine cooperative behavior by suppressing the prosocial effects of positive emotion.

Adhesive/Dentin Interface: The Weak Link in the Composite Restoration

PubMed Central

Spencer, Paulette; Ye, Qiang; Park, Jonggu; Topp, Elizabeth M.; Misra, Anil; Marangos, Orestes; Wang, Yong; Bohaty, Brenda S.; Singh, Viraj; Sene, Fabio; Eslick, John; Camarda, Kyle; Katz, J. Lawrence

2010-01-01

Results from clinical studies suggest that more than half of the 166 million dental restorations that were placed in the United States in 2005 were replacements for failed restorations. This emphasis on replacement therapy is expected to grow as dentists use composite as opposed to dental amalgam to restore moderate to large posterior lesions. Composite restorations have higher failure rates, more recurrent caries, and increased frequency of replacement as compared to amalgam. Penetration of bacterial enzymes, oral fluids, and bacteria into the crevices between the tooth and composite undermines the restoration and leads to recurrent decay and premature failure. Under in vivo conditions the bond formed at the adhesive/dentin interface can be the first defense against these noxious, damaging substances. The intent of this article is to review structural aspects of the clinical substrate that impact bond formation at the adhesive/dentin interface; to examine physico-chemical factors that affect the integrity and durability of the adhesive/dentin interfacial bond; and to explore how these factors act synergistically with mechanical forces to undermine the composite restoration. The article will examine the various avenues that have been pursued to address these problems and it will explore how alterations in material chemistry could address the detrimental impact of physico-chemical stresses on the bond formed at the adhesive/dentin interface. PMID:20195761

Predator attack rate evolution in space: the role of ecology mediated by complex emergent spatial structure and self-shading.

PubMed

Messinger, Susanna M; Ostling, Annette

2013-11-01

Predation interactions are an important element of ecological communities. Population spatial structure has been shown to influence predator evolution, resulting in the evolution of a reduced predator attack rate; however, the evolutionary role of traits governing predator and prey ecology is unknown. The evolutionary effect of spatial structure on a predator's attack rate has primarily been explored assuming a fixed metapopulation spatial structure, and understood in terms of group selection. But endogenously generated, emergent spatial structure is common in nature. Furthermore, the evolutionary influence of ecological traits may be mediated through the spatial self-structuring process. Drawing from theory on pathogens, the evolutionary effect of emergent spatial structure can be understood in terms of self-shading, where a voracious predator limits its long-term invasion potential by reducing local prey availability. Here we formalize the effects of self-shading for predators using spatial moment equations. Then, through simulations, we show that in a spatial context self-shading leads to relationships between predator-prey ecology and the predator's attack rate that are not expected in a non-spatial context. Some relationships are analogous to relationships already shown for host-pathogen interactions, but others represent new trait dimensions. Finally, since understanding the effects of ecology using existing self-shading theory requires simplifications of the emergent spatial structure that do not apply well here, we also develop metrics describing the complex spatial structure of the predator and prey populations to help us explain the evolutionary effect of predator and prey ecology in the context of self-shading. The identification of these metrics may provide a step towards expansion of the predictive domain of self-shading theory to more complex spatial dynamics. Copyright © 2013 Elsevier Inc. All rights reserved.

Undermining capitalism - state ownership and the dialectic of control in the British coal industry

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

Krieger, J.

1983-01-01

The first section of this publication considers state ownership and contradictions of bureaucratic management with regard to the National Coal Board (NCB). Wages policy is discussed in terms of national rationalization, in particular the 1966 National Power Loading Agreement (NPLA). The second section outlines the effects of wage policy and structure upon production and also assesses the effects of work rules which determine organization of labour, division of tasks, norms for co-operation between team and shift groups etc. The third section discusses changes in power and labour relations and demonstrates distinctive regional patterns in the politics of productivity under piece-ratemore » and time-based wage structures. Subsequent sections comprise colliery studies in County Durham and Nottinghamshire. The concluding chapter summarizes the arguments put forward in the preceding sections and discusses the relationship between organizational structure and class power.« less

A relational approach to health practices: towards transcending the agency-structure divide.

PubMed

Veenstra, Gerry; Burnett, Patrick John

2014-02-01

Many health scholars find that Pierre Bourdieu's theory of practice leaves too little room for individual agency. We contend that, by virtue of its relational, field-theoretic underpinnings, the idea of leaving room for agency in Bourdieu's theory of practice is misguided. With agency manifested in interactions and social structures consisting of relations built upon relations, the stark distinction between agency and structure inherent to substantialist thinking is undermined, even dissolved, in a relational field-theoretic context. We also contend that, when treated as relationally bound phenomena, Bourdieu's notions of habitus, doxa, capital and field illuminate creative, adaptive and future-looking practices. We conclude by discussing difficulties inherent to implementing a relational theory of practice in health promotion and public health. © 2014 The Authors. Sociology of Health & Illness © 2014 Foundation for the Sociology of Health & Illness/John Wiley & Sons Ltd.

Adolescents' unconditional acceptance by parents and teachers and educational outcomes: A structural model of gender differences.

PubMed

Makri-Botsari, Evi

2015-08-01

The purpose of this study was to detect gender specific patterns in the network of relations between unconditionality of parental and teacher acceptance in the form of unconditional positive regard and a range of educational outcomes, as indexed by academic self-perception, academic intrinsic motivation, and academic achievement. To test the role of gender as a moderator, a multi-group analysis was employed within the framework of structural equation modelling with increasing restrictions placed on the structural paths across genders. The results on a sample of 427 adolescents in grades 7-9 showed that conditionality of acceptance undermined level of perceived acceptance for both social agents. Moreover, unconditionality of teacher acceptance exerted stronger influences on students' educational outcomes than unconditionality of parental acceptance, with effect sizes being larger for girls than for boys. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Longitudinal Associations Between Relationship Quality and Coparenting Across the Transition to Parenthood: A Dyadic Perspective

PubMed Central

Le, Yunying; McDaniel, Brandon T.; Leavitt, Chelom E.; Feinberg, Mark E.

2016-01-01

The couple and coparenting relationship are theorized to influence one another in a reciprocal manner over time. Empirical evidence demonstrates cross-sectional associations between the two as well as prospective predictions of coparenting by relationship quality and vice versa. However, less is known about the longitudinal reciprocity between the couple relationship and coparenting from the perspective of both parents. The current study sought to examine longitudinal associations between relationship quality and coparenting support/undermining across the transition to parenthood from a dyadic perspective. Participants were 164 cohabitating heterosexual couples expecting their first child assessed during pregnancy and at 6 and 36 months after birth. Actor Partner Interdependence Modeling (APIM) was used to examine, for both men and women, (1) stability over time in relationship quality and coparenting; (2) reciprocal associations between relationship quality and coparenting support/undermining; as well as (3) the gender differences in those associations. Moderate rank-order stability in relationship quality and coparenting support/undermining across the first three years of parenthood was demonstrated. For women, but not men, findings suggested longitudinal reciprocal associations between relationship quality and coparenting support/undermining. Specifically, our findings suggested that prenatal relationship quality sets the stage for coparenting functioning after birth for both men and women but that coparenting functioning is then connected to subsequent feelings about the romantic relationship only for women. PMID:27183188

Work stressors and partner social undermining: Comparing negative affect and psychological detachment as mechanisms.

PubMed

Meier, Laurenz L; Cho, Eunae

2018-05-14

With the mounting evidence that employees' work experiences spill over into the family domain and cross over to family members, it is important to understand the underlying mechanism through which work experiences affect the family domain and what factors may alleviate the adverse impact of work stress. Expanding previous research that mainly focused on the affect-based mechanism (negative affect), the present research investigated a resource-based mechanism (psychological detachment from work) in the relationship linking two work stressors (high workload and workplace incivility) with social undermining toward the partner at home. We also explored the relative strength of the mediating effects of the two mechanisms. In addition, we tested whether relationship satisfaction moderates the proposed effect of detachment on partner undermining. We tested these research questions using two studies with differing designs: a five-wave longitudinal study (N = 470) and a multisource study (N = 131). The results suggest that stressful work experiences affect the family domain via lack of detachment as well as negative affect, that the two pathways have comparable strength, and that high relationship satisfaction mitigates the negative effect of lack of detachment on partner undermining. In sum, this research extends the spillover-crossover model by establishing that poor psychological detachment from work during leisure time is an additional mechanism that links work and family. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

What undermines healthy habits with regard to physical activity and food? Voices of adolescents in a disadvantaged community

PubMed Central

Jonsson, Linus; Larsson, Christel; Berg, Christina; Korp, Peter; Lindgren, Eva-Carin

2017-01-01

ABSTRACT This study aimed to illuminate factors that undermine the healthy habits of adolescents from a multicultural community with low socioeconomic status (S.E.S.) in Sweden with regard to physical activity (P.A.) and food, as stated in their own voices. Adolescents (n = 53, 12–13 y/o) were recruited from one school situated in a multicultural community characterized by low S.E.S. Embracing an interpretive approach, 10 focus-group interviews were conducted to produce data for the study. The focus-group interviews were audio recorded, transcribed verbatim, and analysed using qualitative content analysis. The analysis resulted in two major themes: (1) the availability of temptations is large, and support from the surroundings is limited; and (2) norms and demands set the agenda. The adolescents’ voices illuminate a profound awareness and the magnitude of tempting screen-based activities as undermining their P.A. and healthy food habits. Moreover, several gender boundaries were highlighted as undermining girls’ P.A. and healthy food habits. The adolescents’ stories illuminated that it is difficult for them, within their environment, to establish healthy habits with regard to P.A. and food. To facilitate the adolescents’ healthy habits, we suggest that support from family, friends, the school, and society at large is essential. PMID:28585483

Who counts as family? Family typologies, family support, and family undermining among young adult gay and bisexual men.

PubMed

Soler, Jorge H; Caldwell, Cleopatra H; Córdova, David; Harper, Gary; Bauermeister, José A

2018-06-01

Gay and bisexual men may form chosen families in addition to or in place of families of origin. However, the characteristics of these diverse families remain largely unexamined in the quantitative literature. The purpose of this study was to develop a family typology based on responses from a racially and ethnically diverse sample of young adult gay and bisexual men (YGBM) recruited from the Detroit Metropolitan Area (N=350; 18-29 years old). To explore the role of family, we then examined family social support and social undermining in relation to YGBM psychological distress within different family types. A series of multivariate regressions were used to examine associations between family social support and social undermining with depression and anxiety outcomes. The majority (88%) of YGBM included family of origin in their definitions of family and 63% indicated having chosen families. Associations between family social processes and psychological outcomes varied by type of family, suggesting that family composition shapes how perceptions of support and undermining relate to experiencing symptoms of depression and anxiety. Chosen families play a prominent role in the lives of YGBM and should not be overlooked in family research. Findings also highlight the importance of examining co-occurring family social support and social stress processes to further address psychological distress symptoms among YGBM.

Geostatistics for spatial genetic structures: study of wild populations of perennial ryegrass.

PubMed

Monestiez, P; Goulard, M; Charmet, G

1994-04-01

Methods based on geostatistics were applied to quantitative traits of agricultural interest measured on a collection of 547 wild populations of perennial ryegrass in France. The mathematical background of these methods, which resembles spatial autocorrelation analysis, is briefly described. When a single variable is studied, the spatial structure analysis is similar to spatial autocorrelation analysis, and a spatial prediction method, called "kriging", gives a filtered map of the spatial pattern over all the sampled area. When complex interactions of agronomic traits with different evaluation sites define a multivariate structure for the spatial analysis, geostatistical methods allow the spatial variations to be broken down into two main spatial structures with ranges of 120 km and 300 km, respectively. The predicted maps that corresponded to each range were interpreted as a result of the isolation-by-distance model and as a consequence of selection by environmental factors. Practical collecting methodology for breeders may be derived from such spatial structures.

Adults with Autism Tend to Undermine the Hidden Environmental Structure: Evidence from a Visual Associative Learning Task.

PubMed

Sapey-Triomphe, Laurie-Anne; Sonié, Sandrine; Hénaff, Marie-Anne; Mattout, Jérémie; Schmitz, Christina

2018-04-13

The learning-style theory of Autism Spectrum Disorders (ASD) (Qian, Lipkin, Frontiers in Human Neuroscience 5:77, 2011) states that ASD individuals differ from neurotypics in the way they learn and store information about the environment and its structure. ASD would rather adopt a lookup-table strategy (LUT: memorizing each experience), while neurotypics would favor an interpolation style (INT: extracting regularities to generalize). In a series of visual behavioral tasks, we tested this hypothesis in 20 neurotypical and 20 ASD adults. ASD participants had difficulties using the INT style when instructions were hidden but not when instructions were revealed. Rather than an inability to use rules, ASD would be characterized by a disinclination to generalize and infer such rules.

Incarceration, Prisoner Reentry, and Communities

PubMed Central

Morenoff, Jeffrey D.; Harding, David J.

2014-01-01

Since the mid-1970s the United States has experienced an enormous rise in incarceration and accompanying increases in returning prisoners and in post-release community correctional supervision. Poor urban communities are disproportionately impacted by these phenomena. This review focuses on two complementary questions regarding incarceration, prisoner reentry, and communities:(1) whether and how mass incarceration has affected the social and economic structure of American communities, and (2) how residential neighborhoods affect the social and economic reintegration of returning prisoners. These two questions can be seen as part of a dynamic process involving a pernicious “feedback” loop, in which mass incarceration undermines the structure and social organization of some communities, thus creating more criminogenic environments for returning prisoners and further diminishing their prospects for successful reentry and reintegration. PMID:25400321

Doping and band gap control at poly(vinylidene fluoride)/graphene interface

NASA Astrophysics Data System (ADS)

Cai, Jia; Wang, Jian-Lu; Gao, Heng; Tian, Bobo; Gong, Shi-Jing; Duan, Chun-Gang; Chu, Jun-Hao

2018-05-01

Using the density-functional first-principles calculations, we investigate the electronic structures of poly(vinylidene fluoride) PVDF/graphene composite systems. The n- and p-doping of graphene can be flexibly switched by reversing the ferroelectric polarization of PVDF, without scarifying the intrinsic π-electron band dispersions of graphene that are usually undermined by chemical doping. The doping degree is also dependent on the thickness of PVDF layers, which will get saturated when PVDF is thick enough. In PVDF/bilayer graphene (BLG) heterostructure, the doping degree directly determines the local energy gap of the charged BLG. The sandwich structure of PVDF/BLG/PVDF can further enhance the local energy gap as well as keep the electric neutrality of BLG, which will be of great application potentials in graphene-based nanoelectronics.

Structure and mechanism of human DNA polymerase [eta

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

Biertümpfel, Christian; Zhao, Ye; Kondo, Yuji

2010-11-03

The variant form of the human syndrome xeroderma pigmentosum (XPV) is caused by a deficiency in DNA polymerase {eta} (Pol{eta}), a DNA polymerase that enables replication through ultraviolet-induced pyrimidine dimers. Here we report high-resolution crystal structures of human Pol{eta} at four consecutive steps during DNA synthesis through cis-syn cyclobutane thymine dimers. Pol{eta} acts like a 'molecular splint' to stabilize damaged DNA in a normal B-form conformation. An enlarged active site accommodates the thymine dimer with excellent stereochemistry for two-metal ion catalysis. Two residues conserved among Pol{eta} orthologues form specific hydrogen bonds with the lesion and the incoming nucleotide to assistmore » translesion synthesis. On the basis of the structures, eight Pol{eta} missense mutations causing XPV can be rationalized as undermining the molecular splint or perturbing the active-site alignment. The structures also provide an insight into the role of Pol{eta} in replicating through D loop and DNA fragile sites.« less

Extrinsic rewards undermine altruistic tendencies in 20-month-olds.

PubMed

Warneken, Felix; Tomasello, Michael

2008-11-01

The current study investigated the influence of rewards on very young children's helping behavior. After 20-month-old infants received a material reward during a treatment phase, they subsequently were less likely to engage in further helping during a test phase as compared with infants who had previously received social praise or no reward at all. This so-called overjustification effect suggests that even the earliest helping behaviors of young children are intrinsically motivated and that socialization practices involving extrinsic rewards can undermine this tendency.

Spatial localization in heterogeneous systems

NASA Astrophysics Data System (ADS)

Kao, Hsien-Ching; Beaume, Cédric; Knobloch, Edgar

2014-01-01

We study spatial localization in the generalized Swift-Hohenberg equation with either quadratic-cubic or cubic-quintic nonlinearity subject to spatially heterogeneous forcing. Different types of forcing (sinusoidal or Gaussian) with different spatial scales are considered and the corresponding localized snaking structures are computed. The results indicate that spatial heterogeneity exerts a significant influence on the location of spatially localized structures in both parameter space and physical space, and on their stability properties. The results are expected to assist in the interpretation of experiments on localized structures where departures from spatial homogeneity are generally unavoidable.

Meta-ecosystem dynamics and functioning on finite spatial networks

PubMed Central

Marleau, Justin N.; Guichard, Frédéric; Loreau, Michel

2014-01-01

The addition of spatial structure to ecological concepts and theories has spurred integration between sub-disciplines within ecology, including community and ecosystem ecology. However, the complexity of spatial models limits their implementation to idealized, regular landscapes. We present a model meta-ecosystem with finite and irregular spatial structure consisting of local nutrient–autotrophs–herbivores ecosystems connected through spatial flows of materials and organisms. We study the effect of spatial flows on stability and ecosystem functions, and provide simple metrics of connectivity that can predict these effects. Our results show that high rates of nutrient and herbivore movement can destabilize local ecosystem dynamics, leading to spatially heterogeneous equilibria or oscillations across the meta-ecosystem, with generally increased meta-ecosystem primary and secondary production. However, the onset and the spatial scale of these emergent dynamics depend heavily on the spatial structure of the meta-ecosystem and on the relative movement rate of the autotrophs. We show how this strong dependence on finite spatial structure eludes commonly used metrics of connectivity, but can be predicted by the eigenvalues and eigenvectors of the connectivity matrix that describe the spatial structure and scale. Our study indicates the need to consider finite-size ecosystems in meta-ecosystem theory. PMID:24403323

Reproductive cloning, genetic engineering and the autonomy of the child: the moral agent and the open future.

PubMed

Mameli, M

2007-02-01

Some authors have argued that the human use of reproductive cloning and genetic engineering should be prohibited because these biotechnologies would undermine the autonomy of the resulting child. In this paper, two versions of this view are discussed. According to the first version, the autonomy of cloned and genetically engineered people would be undermined because knowledge of the method by which these people have been conceived would make them unable to assume full responsibility for their actions. According to the second version, these biotechnologies would undermine autonomy by violating these people's right to an open future. There is no evidence to show that people conceived through cloning and genetic engineering would inevitably or even in general be unable to assume responsibility for their actions; there is also no evidence for the claim that cloning and genetic engineering would inevitably or even in general rob the child of the possibility to choose from a sufficiently large array of life plans.

Reproductive cloning, genetic engineering and the autonomy of the child: the moral agent and the open future

PubMed Central

Mameli, M

2007-01-01

Some authors have argued that the human use of reproductive cloning and genetic engineering should be prohibited because these biotechnologies would undermine the autonomy of the resulting child. In this paper, two versions of this view are discussed. According to the first version, the autonomy of cloned and genetically engineered people would be undermined because knowledge of the method by which these people have been conceived would make them unable to assume full responsibility for their actions. According to the second version, these biotechnologies would undermine autonomy by violating these people's right to an open future. There is no evidence to show that people conceived through cloning and genetic engineering would inevitably or even in general be unable to assume responsibility for their actions; there is also no evidence for the claim that cloning and genetic engineering would inevitably or even in general rob the child of the possibility to choose from a sufficiently large array of life plans. PMID:17264194

Spatial Abilities of High-School Students in the Perception of Geologic Structures.

ERIC Educational Resources Information Center

Kali, Yael; Orion, Nir

1996-01-01

Characterizes specific spatial abilities required in geology studies through the examination of the performance of high school students in solving structural geology problems on the geologic spatial ability test (GeoSAT). Concludes that visual penetration ability and the ability to perceive the spatial configuration of the structure are…

Local Nordic tobacco interests collaborated with multinational companies to maintain a united front and undermine tobacco control policies.

PubMed

Hiilamo, Heikki; Glantz, Stanton A

2013-03-01

To analyse how local tobacco companies in the Nordic countries, individually and through National Manufacturers' Associations, cooperated with British American Tobacco and Philip Morris in denying the health hazards of smoking and undermining tobacco control. Analysis of tobacco control policies in the Nordic countries and tobacco industry documents. Nordic countries were early adopters of tobacco control policies. The multinational tobacco companies recognised this fact and mobilised to oppose these policies, in part because of fear that they would set unfavourable precedents. Since at least 1972, the Nordic tobacco companies were well informed about and willing to participate in the multinational companies activities to obscure the health dangers of smoking and secondhand smoke and to oppose tobacco control policies. Cooperation between multinational companies, Nordic national manufacturer associations and local companies ensured a united front on smoking and health issues in the Nordic area that was consistent with the positions that the multinational companies were taking. This cooperation delayed smoke-free laws and undermined other tobacco control measures. Local tobacco companies worked with multinational companies to undermine tobacco control in distant and small Nordic markets because of concern that pioneering policies initiated in Nordic countries would spread to bigger market areas. Claims by the local Nordic companies that they were not actively involved with the multinationals are not supported by the facts. These results also demonstrate that the industry appreciates the global importance of both positive and negative public health precedents in tobacco control.

THE NATURE OF FOSSIL GALAXY GROUPS: ARE THEY REALLY FOSSILS?

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

La Barbera, F.; Sorrentino, G.; De Carvalho, R. R.

We use SDSS-DR4 photometric and spectroscopic data out to redshift z {approx} 0.1 combined with ROSAT All Sky Survey X-ray data to produce a sample of 25 fossil groups (FGs), defined as bound systems dominated by a single, luminous elliptical galaxy with extended X-ray emission. We examine possible biases introduced by varying the parameters used to define the sample, and the main pitfalls are also discussed. The spatial density of FGs, estimated via the V/V {sub MAX} test, is 2.83 x 10{sup -6} h {sup 3} {sub 75} Mpc{sup -3} for L{sub X} > 0.89 x 10{sup 42} h {supmore » -2} {sub 75} erg s{sup -1} consistent with Vikhlinin et al., who examined an X-ray overluminous elliptical galaxy sample (OLEG). We compare the general properties of FGs identified here with a sample of bright field ellipticals generated from the same data set. These two samples show no differences in the distribution of neighboring faint galaxy density excess, distance from the red sequence in the color-magnitude diagram, and structural parameters such as a {sub 4} and internal color gradients. Furthermore, examination of stellar populations shows that our 25 FGs have similar ages, metallicities, and {alpha}-enhancement as the bright field ellipticals, undermining the idea that these systems represent fossils of a physical mechanism that occurred at high redshift. Our study reveals no difference between FGs and field ellipticals, suggesting that FGs might not be a distinct family of true fossils, but rather the final stage of mass assembly in the universe.« less

Relation of frontal N100 to psychopathy-related differences in selective attention☆

PubMed Central

Hamilton, Rachel K. Bencic; Baskin-Sommers, Arielle R.; Newman, Joseph P.

2015-01-01

Research indicates that psychopathy may be characterized by early attentional abnormalities that undermine the processing of peripheral information during goal-directed activity (Baskin-Sommers & Newman, 2012). Past work has found that psychopathic individuals show reduced interference on the Box Stroop task, in which color names are spatially separated from (i.e., peripheral to) colored stimuli (Hiatt, Schmitt, & Newman, 2004). The present study sought to replicate and extend these findings. A priori predictions were that psychopathy scores would be inversely related to interference and that psychopathy-related differences in Box Stroop conflict processing would emerge at an early stage as measured by event-related potentials (ERP). Results supported both hypotheses. Moreover, the association between the early attention-related component (N100) and interference was moderated by level of psychopathy. These findings suggest that psychopathic individuals have less coordinated responses to conflict than healthy individuals, a conjecture that has implications for information integration and self-regulation. PMID:25179538

Relation of frontal N100 to psychopathy-related differences in selective attention.

PubMed

Hamilton, Rachel K Bencic; Baskin-Sommers, Arielle R; Newman, Joseph P

2014-12-01

Research indicates that psychopathy may be characterized by early attentional abnormalities that undermine the processing of peripheral information during goal-directed activity (Baskin-Sommers & Newman, 2012). Past work has found that psychopathic individuals show reduced interference on the Box Stroop task, in which color names are spatially separated from (i.e., peripheral to) colored stimuli (Hiatt, Schmitt, & Newman, 2004). The present study sought to replicate and extend these findings. A priori predictions were that psychopathy scores would be inversely related to interference and that psychopathy-related differences in Box Stroop conflict processing would emerge at an early stage as measured by event-related potentials (ERP). Results supported both hypotheses. Moreover, the association between the early attention-related component (N100) and interference was moderated by level of psychopathy. These findings suggest that psychopathic individuals have less coordinated responses to conflict than healthy individuals, a conjecture that has implications for information integration and self-regulation. Copyright © 2014 Elsevier B.V. All rights reserved.

Factors affecting graded and ungraded memory loss following hippocampal lesions.

PubMed

Winocur, Gordon; Moscovitch, Morris; Sekeres, Melanie J

2013-11-01

This review evaluates three current theories--Standard Consolidation (Squire & Wixted, 2011), Overshadowing (Sutherland, Sparks, & Lehmann, 2010), and Multiple Trace-Transformation (Winocur, Moscovitch, & Bontempi, 2010)--in terms of their ability to account for the role of the hippocampus in recent and remote memory in animals. Evidence, based on consistent findings from tests of spatial memory and memory for acquired food preferences, favours the transformation account, but this conclusion is undermined by inconsistent results from studies that measured contextual fear memory, probably the most commonly used test of hippocampal involvement in anterograde and retrograde memory. Resolution of this issue may depend on exercising greater control over critical factors (e.g., contextual environment, amount of pre-exposure to the conditioning chamber, the number and distribution of foot-shocks) that can affect the representation of the memory shortly after learning and over the long-term. Research strategies aimed at characterizing the neural basis of long-term consolidation/transformation, as well as other outstanding issues are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

The case for transforming governmental public health.

PubMed

Salinsky, Eileen; Gursky, Elin A

2006-01-01

Changing threats to the public's health necessitate a profound transformation of the public health enterprise. Despite recent attention to the biodefense role of public health, policymakers have not developed a clear, realistic vision for the structure and functionality of the governmental public health system. Lack of leadership and organizational disconnects across levels of government have prevented strategic alignment of resources and undermined momentum for meaningful change. A transformed public health system is needed to address the demands of emergency preparedness and health protection. Such transformation should include focused, risk-based resource allocation; regional planning; technological upgrades; workforce restructuring; improved integration of private-sector assets; and better performance monitoring.

Debating Organ Procurement Policy Without Illusions.

PubMed

Hippen, Benjamin

2015-10-01

In this perspective, I review and critique claims that the transplant waiting list overstates the demand for kidneys and correct a few mischaracterizations of some structural barriers to increasing rates of transplantation. The solutions to the shortage of organs proffered by opponents of financial incentives fail to account for a panoply of clinical, regulatory, and financial realities of transplantation centers in the United States in ways that undermine the thesis that a trial of financial incentives for organ procurement is not warranted at this time. I conclude with some personal pessimistic reflections on the progress of this debate. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Rethinking gender, heterosexual men, and women's vulnerability to HIV/AIDS.

PubMed

Higgins, Jenny A; Hoffman, Susie; Dworkin, Shari L

2010-03-01

Most HIV prevention literature portrays women as especially vulnerable to HIV infection because of biological susceptibility and men's sexual power and privilege. Conversely, heterosexual men are perceived as active transmitters of HIV but not active agents in prevention. Although the women's vulnerability paradigm was a radical revision of earlier views of women in the epidemic, mounting challenges undermine its current usefulness. We review the etiology and successes of the paradigm as well as its accruing limitations. We also call for an expanded model that acknowledges biology, gender inequality, and gendered power relations but also directly examines social structure, gender, and HIV risk for heterosexual women and men.

Boycunts and bonus holes: trans men's bodies, neoliberalism, and the sexual productivity of genitals.

PubMed

Edelman, Elijah Adiv; Zimman, Lal

2014-01-01

Recent theorizations of trans embodiment have brought attention to the ways neoliberalism limits the productivity of nonnormatively gendered bodies. This article deals with the discursive framing of embodiment and sexual desirability among trans men and other transmasculine persons negotiating Internet-mediated homoerotic spaces. Micro-level analysis of discourse structure and macro-level analysis of socio-political context together show how trans men navigate homonormative sexual economies by linguistically recuperating their bodies' sexually productivity. Instead of undermining claims of embodied masculinity and homoerotic value, potential sites of exclusion-i.e., trans genitals-become sites of flexible accumulation that enhance rather than detract from their bearers' desirability.

Systems Thinking to Improve the Public’s Health

PubMed Central

Leischow, Scott J.; Best, Allan; Trochim, William M.; Clark, Pamela I.; Gallagher, Richard S.; Marcus, Stephen E.; Matthews, Eva

2014-01-01

Improving population health requires understanding and changing societal structures and functions, but countervailing forces sometimes undermine those changes, thus reflecting the adaptive complexity inherent in public health systems. The purpose of this paper is to propose systems thinking as a conceptual rubric for the practice of team science in public health, and transdisciplinary, translational research as a catalyst for promoting the functional efficiency of science. The paper lays a foundation for the conceptual understanding of systems thinking and transdisciplinary research, and will provide illustrative examples within and beyond public health. A set of recommendations for a systems-centric approach to translational science will be presented. PMID:18619400

Rethinking Gender, Heterosexual Men, and Women's Vulnerability to HIV/AIDS

PubMed Central

Hoffman, Susie; Dworkin, Shari L.

2010-01-01

Most HIV prevention literature portrays women as especially vulnerable to HIV infection because of biological susceptibility and men's sexual power and privilege. Conversely, heterosexual men are perceived as active transmitters of HIV but not active agents in prevention. Although the women's vulnerability paradigm was a radical revision of earlier views of women in the epidemic, mounting challenges undermine its current usefulness. We review the etiology and successes of the paradigm as well as its accruing limitations. We also call for an expanded model that acknowledges biology, gender inequality, and gendered power relations but also directly examines social structure, gender, and HIV risk for heterosexual women and men. PMID:20075321

Effect of long-term mechanical perturbation on intertidal soft-bottom meiofaunal community spatial structure

NASA Astrophysics Data System (ADS)

Boldina, Inna; Beninger, Peter G.; Le Coz, Maïwen

2014-01-01

Situated at the interface of the microbial and macrofaunal compartments, soft-bottom meiofauna accomplish important ecological functions. However, little is known of their spatial distribution in the benthic environment. To assess the effects of long-term mechanical disturbance on soft-bottom meiofaunal spatial distribution, we compared a site subjected to long-term clam digging to a nearby site untouched by such activities, in Bourgneuf Bay, on the Atlantic coast of France. Six patterned replicate samples were taken at 3, 6, 9, 12, 15, 18, 21 and 24 cm lags, all sampling stations being separated by 5 m. A combined correlogram-variogram approach was used to enhance interpretation of the meiofaunal spatial distribution; in particular, the definition of autocorrelation strength and its statistical significance, as well as the detailed characteristics of the periodic spatial structure of nematode assemblages, and the determination of the maximum distance of their spatial autocorrelation. At both sites, nematodes and copepods clearly exhibited aggregated spatial structure at the meso scale; this structure was attenuated at the impacted site. The nematode spatial distribution showed periodicity at the non-impacted site, but not at the impacted site. This is the first explicit report of a periodic process in meiofaunal spatial distribution. No such cyclic spatial process was observed for the more motile copepods at either site. This first study to indicate the impacts of long-term anthropogenic mechanical perturbation on meiofaunal spatial structure opens the door to a new dimension of mudflat ecology. Since macrofaunal predator search behaviour is known to be strongly influenced by prey spatial structure, the alteration of this structure may have important consequences for ecosystem functioning.

Many-to-one form-to-function mapping weakens parallel morphological evolution.

PubMed

Thompson, Cole J; Ahmed, Newaz I; Veen, Thor; Peichel, Catherine L; Hendry, Andrew P; Bolnick, Daniel I; Stuart, Yoel E

2017-11-01

Evolutionary ecologists aim to explain and predict evolutionary change under different selective regimes. Theory suggests that such evolutionary prediction should be more difficult for biomechanical systems in which different trait combinations generate the same functional output: "many-to-one mapping." Many-to-one mapping of phenotype to function enables multiple morphological solutions to meet the same adaptive challenges. Therefore, many-to-one mapping should undermine parallel morphological evolution, and hence evolutionary predictability, even when selection pressures are shared among populations. Studying 16 replicate pairs of lake- and stream-adapted threespine stickleback (Gasterosteus aculeatus), we quantified three parts of the teleost feeding apparatus and used biomechanical models to calculate their expected functional outputs. The three feeding structures differed in their form-to-function relationship from one-to-one (lower jaw lever ratio) to increasingly many-to-one (buccal suction index, opercular 4-bar linkage). We tested for (1) weaker linear correlations between phenotype and calculated function, and (2) less parallel evolution across lake-stream pairs, in the many-to-one systems relative to the one-to-one system. We confirm both predictions, thus supporting the theoretical expectation that increasing many-to-one mapping undermines parallel evolution. Therefore, sole consideration of morphological variation within and among populations might not serve as a proxy for functional variation when multiple adaptive trait combinations exist. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

Advances in in situ inspection of automated fiber placement systems

NASA Astrophysics Data System (ADS)

Juarez, Peter D.; Cramer, K. Elliott; Seebo, Jeffrey P.

2016-05-01

Automated Fiber Placement (AFP) systems have been developed to help take advantage of the tailorability of composite structures in aerospace applications. AFP systems allow the repeatable placement of uncured, spool fed, preimpregnated carbon fiber tape (tows) onto substrates in desired thicknesses and orientations. This automated process can incur defects, such as overlapping tow lines, which can severely undermine the structural integrity of the part. Current defect detection and abatement methods are very labor intensive, and still mostly rely on human manual inspection. Proposed is a thermographic in situ inspection technique which monitors tow placement with an on board thermal camera using the preheated substrate as a through transmission heat source. An investigation of the concept is conducted, and preliminary laboratory results are presented. Also included will be a brief overview of other emerging technologies that tackle the same issue.

An investigation of the development of the topological spatial structures in elementary school students

NASA Astrophysics Data System (ADS)

Everett, Susan Ann

1999-09-01

In this study the relationships among the topological spatial structures were examined in students in kindergarten, second, and fourth grades. These topological spatial structures are part of the three major types of spatial thinking: topological, projective, and Euclidean (as defined by Jean Piaget and associates). According to Piaget's model of spatial thinking, the spatial structures enable humans to think about spatial relationships at a conceptual or representational level rather than only at a simpler, perceptual level. The clinical interview technique was used to interact individually with 72 children to assess the presence of each of the different topological spatial structures. This was accomplished through the use of seven task protocols and simple objects which are familiar to young children. These task protocols allowed the investigator to interact with each child in a consistent manner. The results showed that most of the children in this study (97.2%) had not developed all of the topological spatial structures. The task scores, were analyzed using non-parametric statistical tests due to the ordinal nature of the data. From the data the following results were obtained: (1) the spatial structures did not develop in random order based on the task scores but developed in the sequence expected from Piaget's model, (2) task performance improved with grade level with fourth grade students outperforming second graders and kindergartners on each of the seven tasks, and (3) no significant differences on task performance due to gender were found. Based on these results, young elementary children are beginning to develop topological spatial thinking. This is critical since it provides the foundation for the other types of spatial thinking, projective and Euclidean. Since spatial thinking is not a "gift" but can be developed, educators need to provide more opportunities for students to increase their level of spatial thinking since it is necessary for conceptual understanding of many different topics in math and science.

Do Increasingly Globalized Land Systems Promote or Undermine Sustainability?

NASA Astrophysics Data System (ADS)

Munroe, D. K.

2015-12-01

Scholars are now studying land systems in a global context using such concepts as "telecoupling." Research to date has recognized that local land systems may be undermined by globalization, and local people displaced. The land change community emphasizes the ways in which local people make decisions about natural resources given the opportunities and constraints that globalization presents. This talk will present a summary of current land systems science research in agribusiness, global trade and financial institutions, highlighting key ways in which sustainability measures can capture the effects of these actors and activities.

Community mapping of sex work criminalization and violence: impacts on HIV treatment interruptions among marginalized women living with HIV in Vancouver, Canada.

PubMed

Goldenberg, Shira M; Deering, Kathleen; Amram, Ofer; Guillemi, Silvia; Nguyen, Paul; Montaner, Julio; Shannon, Kate

2017-09-01

Despite the high HIV burden faced by sex workers, data on access and retention in antiretroviral therapy (ART) are limited. Using an innovative spatial epidemiological approach, we explored how the social geography of sex work criminalization and violence impacts HIV treatment interruptions among sex workers living with HIV in Vancouver over a 3.5-year period. Drawing upon data from a community-based cohort (AESHA, 2010-2013) and linked external administrative data on ART dispensation, GIS mapping and multivariable logistic regression with generalized estimating equations to prospectively examine the effects of spatial criminalization and violence near women's places of residence on 2-day ART interruptions. Analyses were restricted to 66 ART-exposed women who contributed 208 observations and 83 ART interruption events. In adjusted multivariable models, heightened density of displacement due to policing independently correlated with HIV treatment interruptions (AOR: 1.02, 95%CI: 1.00-1.04); density of legal restrictions (AOR: 1.30, 95%CI: 0.97-1.76) and a combined measure of criminalization/violence (AOR: 1.00, 95%CI: 1.00-1.01) were marginally correlated. The social geography of sex work criminalization may undermine access to essential medicines, including HIV treatment. Interventions to promote 'enabling environments' (e.g. peer-led models, safer living/working spaces) should be explored, alongside policy reforms to ensure uninterrupted treatment access.

The complex roles of space and environment in structuring functional, taxonomic and phylogenetic beta diversity of frogs in the Atlantic Forest

PubMed Central

Luiz, Amom Mendes; Sawaya, Ricardo J.

2018-01-01

Ecological communities are complex entities that can be maintained and structured by niche-based processes such as environmental conditions, and spatial processes such as dispersal. Thus, diversity patterns may be shaped simultaneously at different spatial scales by very distinct processes. Herein we assess whether and how functional, taxonomic, and phylogenetic beta diversities of frog tadpoles are explained by environmental and/or spatial predictors. We implemented a distance–based redundancy analysis to explore variation in components of beta diversity explained by pure environmental and pure spatial predictors, as well as their interactions, at both fine and broad spatial scales. Our results indicated important but complex roles of spatial and environmental predictors in structuring phylogenetic, taxonomic and functional beta diversities. The pure fine-scales spatial fraction was more important in structuring all beta diversity components, especially to functional and taxonomical spatial turnover. Environmental variables such as canopy cover and vegetation structure were important predictors of all components, but especially to functional and taxonomic beta diversity. We emphasize that distinct factors related to environment and space are affecting distinct components of beta diversity in different ways. Although weaker, phylogenetic beta diversity, which is structured more on biogeographical scales, and thus can be represented by spatially structured processes, was more related to broad spatial processes than other components. However, selected fine-scale spatial predictors denoted negative autocorrelation, which may be revealing the existence of differences in unmeasured habitat variables among samples. Although overall important, local environmental-based processes explained better functional and taxonomic beta diversity, as these diversity components carry an important ecological value. We highlight the importance of assessing different components of diversity patterns at different scales by spatially explicit models in order to improve our understanding of community structure and help to unravel the complex nature of biodiversity. PMID:29672575

Weak Compliance Undermines the Success of No-Take Zones in a Large Government-Controlled Marine Protected Area

PubMed Central

Campbell, Stuart J.; Hoey, Andrew S.; Maynard, Jeffrey; Kartawijaya, Tasrif; Cinner, Joshua; Graham, Nicholas A. J.; Baird, Andrew H.

2012-01-01

The effectiveness of marine protected areas depends largely on whether people comply with the rules. We quantified temporal changes in benthic composition, reef fish biomass, and fishing effort among marine park zones (including no-take areas) to assess levels of compliance following the 2005 rezoning of the government-controlled Karimunjawa National Park (KNP), Indonesia. Four years after the rezoning awareness of fishing regulations was high amongst local fishers, ranging from 79.5±7.9 (SE) % for spatial restrictions to 97.7±1.2% for bans on the use of poisons. Despite this high awareness and strong compliance with gear restrictions, compliance with spatial restrictions was weak. In the four years following the rezoning reef fish biomass declined across all zones within KNP, with >50% reduction within the no-take Core and Protection Zones. These declines were primarily driven by decreases in the biomass of groups targeted by local fishers; planktivores, herbivores, piscivores, and invertivores. These declines in fish biomass were not driven by changes in habitat quality; coral cover increased in all zones, possibly as a result of a shift in fishing gears from those which can damage reefs (i.e., nets) to those which cause little direct damage (i.e., handlines and spears). Direct observations of fishing activities in 2009 revealed there was limited variation in fishing effort between zones in which fishing was allowed or prohibited. The apparent willingness of the KNP communities to comply with gear restrictions, but not spatial restrictions is difficult to explain and highlights the complexities of the social and economic dynamics that influence the ecological success of marine protected areas. Clearly the increased and high awareness of fishery restrictions following the rezoning is a positive step. The challenge now is to understand and foster the conditions that may facilitate compliance with spatial restrictions within KNP and marine parks worldwide. PMID:23226237

Inefficient procurement processes undermine access to medicines in the Western Cape Province of South Africa.

PubMed

Magadzire, Bvudzai P; Ward, Kim; Leng, Henry M J; Sanders, David

2017-06-30

South Africa (SA) has experienced several stock-outs of life-saving medicines for the treatment of major chronic infectious and non-communicable diseases in the public sector. To identify the causes of stock-outs and to illustrate how they undermine access to medicines (ATM) in the Western Cape Province, SA. This qualitative study was conducted with a sample of over 70 key informants (frontline health workers, sub-structure and provincial health service managers). We employed the critical incident technique to identify significant occurrences in our context, the consequences of which impacted on access to medicines during a defined period. Stock-outs were identified as one such incident, and we explored when, where and why they occurred, in order to inform policy and practice. Medicines procurement is a centralised function in SA. Health service managers unanimously agreed that stock-outs resulted from the following inefficiencies at the central level: (i) delays in awarding of pharmaceutical tenders; (ii) absence of contracts for certain medicines appearing on provincial code lists; and (iii) suppliers' inability to satisfy contractual agreements. The recurrence of stock-outs had implications at multiple levels: (i) health facility operations; (ii) the Chronic Dispensing Unit (CDU), which prepacks medicines for over 300 000 public sector patients; and (iii) community-based medicines distribution systems, which deliver the CDU's prepacked medicines to non-health facilities nearer to patient homes. For instance, stock-outs resulted in omission of certain medicines from CDU parcels that were delivered to health facilities. This increased workload and caused frustration for frontline health workers who were expected to dispense omitted medicines manually. According to frontline health workers, this translated into longer waiting times for patients and associated dissatisfaction. In some instances, patients were asked to return for undispensed medication at a later date, which could potentially affect adherence to treatment and therapeutic outcomes. Stock-outs therefore undermined the intended benefits of ATM strategies. Addressing the procurement challenges, most notably timeous tender awards and supplier performance management, is critical for successful implementation of ATM strategies.

Beer for "brohood": A laboratory simulation of masculinity confirmation through alcohol use behaviors in men.

PubMed

Fugitt, Jessica L; Ham, Lindsay S

2018-05-01

Though alcohol use is a widespread behavior, men tend to drink more and experience more alcohol-related negative consequences than do women. Research suggests that individuals are motivated to maintain ingroup status by engaging in behaviors prototypical of the ingroup when group status has been threatened, and that men are particularly likely to do this when masculine ingroup status is threatened. The present study investigated masculine drinking behaviors through a social lens, examining the impact of masculinity threat on alcohol consumption in a simulated bar laboratory. Sixty-five male students ages 21-29 years (Mage = 22.66; 74% White) consumed beer in a taste-test paradigm after being exposed to randomly assigned personality feedback relative to gender standards. This feedback suggested that they were either low in masculinity (threat condition, n = 22) or high in masculinity (control condition, n = 22). A third condition received the low-masculinity feedback and then were exposed to information to undermine masculine alcohol use norms (undermine condition, n = 21) to account for negative affect reduction motives for use. As hypothesized, individuals in the threat condition consumed significantly more alcohol than those in the control and undermine conditions, even though the threat and undermine conditions reported similar levels of negative affect following masculinity threat. These results suggest that consumption of alcohol by men in social contexts may be strongly motivated by the desire to confirm masculine status. This understanding may be used to enhance the effectiveness of alcohol use intervention protocols. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition.

PubMed

Kuhbandner, Christof; Aslan, Alp; Emmerdinger, Kathrin; Murayama, Kou

2016-01-01

Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one-third of the words were tested and one-third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After 1 week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance-contingent reward in a test can undermine long-term knowledge acquisition.

Local Nordic tobacco interests collaborated with multinational companies to maintain a united front and undermine tobacco control policies

PubMed Central

Hiilamo, Heikki; Glantz, Stanton A

2012-01-01

Objective To analyse how local tobacco companies in the Nordic countries, individually and through National Manufacturers’ Associations, cooperated with British American Tobacco and Philip Morris in denying the health hazards of smoking and undermining tobacco control. Methods Analysis of tobacco control policies in the Nordic countries and tobacco industry documents. Results Nordic countries were early adopters of tobacco control policies. The multinational tobacco companies recognised this fact and mobilised to oppose these policies, in part because of fear that they would set unfavourable precedents. Since at least 1972, the Nordic tobacco companies were well informed about and willing to participate in the multinational companies activities to obscure the health dangers of smoking and secondhand smoke and to oppose tobacco control policies. Cooperation between multinational companies, Nordic national manufacturer associations and local companies ensured a united front on smoking and health issues in the Nordic area that was consistent with the positions that the multinational companies were taking. This cooperation delayed smoke-free laws and undermined other tobacco control measures. Conclusions Local tobacco companies worked with multinational companies to undermine tobacco control in distant and small Nordic markets because of concern that pioneering policies initiated in Nordic countries would spread to bigger market areas. Claims by the local Nordic companies that they were not actively involved with the multinationals are not supported by the facts. These results also demonstrate that the industry appreciates the global importance of both positive and negative public health precedents in tobacco control. PMID:22199013

Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition

PubMed Central

Kuhbandner, Christof; Aslan, Alp; Emmerdinger, Kathrin; Murayama, Kou

2016-01-01

Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one-third of the words were tested and one-third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After 1 week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance–contingent reward in a test can undermine long-term knowledge acquisition. PMID:26869978

Human movement data for malaria control and elimination strategic planning.

PubMed

Pindolia, Deepa K; Garcia, Andres J; Wesolowski, Amy; Smith, David L; Buckee, Caroline O; Noor, Abdisalan M; Snow, Robert W; Tatem, Andrew J

2012-06-18

Recent increases in funding for malaria control have led to the reduction in transmission in many malaria endemic countries, prompting the national control programmes of 36 malaria endemic countries to set elimination targets. Accounting for human population movement (HPM) in planning for control, elimination and post-elimination surveillance is important, as evidenced by previous elimination attempts that were undermined by the reintroduction of malaria through HPM. Strategic control and elimination planning, therefore, requires quantitative information on HPM patterns and the translation of these into parasite dispersion. HPM patterns and the risk of malaria vary substantially across spatial and temporal scales, demographic and socioeconomic sub-groups, and motivation for travel, so multiple data sets are likely required for quantification of movement. While existing studies based on mobile phone call record data combined with malaria transmission maps have begun to address within-country HPM patterns, other aspects remain poorly quantified despite their importance in accurately gauging malaria movement patterns and building control and detection strategies, such as cross-border HPM, demographic and socioeconomic stratification of HPM patterns, forms of transport, personal malaria protection and other factors that modify malaria risk. A wealth of data exist to aid filling these gaps, which, when combined with spatial data on transport infrastructure, traffic and malaria transmission, can answer relevant questions to guide strategic planning. This review aims to (i) discuss relevant types of HPM across spatial and temporal scales, (ii) document where datasets exist to quantify HPM, (iii) highlight where data gaps remain and (iv) briefly put forward methods for integrating these datasets in a Geographic Information System (GIS) framework for analysing and modelling human population and Plasmodium falciparum malaria infection movements.

Human movement data for malaria control and elimination strategic planning

PubMed Central

2012-01-01

Recent increases in funding for malaria control have led to the reduction in transmission in many malaria endemic countries, prompting the national control programmes of 36 malaria endemic countries to set elimination targets. Accounting for human population movement (HPM) in planning for control, elimination and post-elimination surveillance is important, as evidenced by previous elimination attempts that were undermined by the reintroduction of malaria through HPM. Strategic control and elimination planning, therefore, requires quantitative information on HPM patterns and the translation of these into parasite dispersion. HPM patterns and the risk of malaria vary substantially across spatial and temporal scales, demographic and socioeconomic sub-groups, and motivation for travel, so multiple data sets are likely required for quantification of movement. While existing studies based on mobile phone call record data combined with malaria transmission maps have begun to address within-country HPM patterns, other aspects remain poorly quantified despite their importance in accurately gauging malaria movement patterns and building control and detection strategies, such as cross-border HPM, demographic and socioeconomic stratification of HPM patterns, forms of transport, personal malaria protection and other factors that modify malaria risk. A wealth of data exist to aid filling these gaps, which, when combined with spatial data on transport infrastructure, traffic and malaria transmission, can answer relevant questions to guide strategic planning. This review aims to (i) discuss relevant types of HPM across spatial and temporal scales, (ii) document where datasets exist to quantify HPM, (iii) highlight where data gaps remain and (iv) briefly put forward methods for integrating these datasets in a Geographic Information System (GIS) framework for analysing and modelling human population and Plasmodium falciparum malaria infection movements. PMID:22703541

Conflict of interest and FCTC implementation in China.

PubMed

Wan, Xia; Ma, Shaojun; Hoek, Janet; Yang, Jie; Wu, Lanyan; Zhou, Jiushun; Yang, Gonghuan

2012-07-01

To critically review the structure of tobacco control policy making in China, examine conflicts of interest within this structure, and consider how these affected the introduction of on-pack warnings. Government policy documents and warning labels were obtained and critically reviewed. Few differences exist between the on-pack warnings formerly used in China and those introduced ostensibly to meet Framework Convention on Tobacco Control (FCTC) obligations. Comparison with tobacco manufactured for export or overseas consumption shows the new Chinese domestic on-pack warnings are demonstrably inferior to those required internationally. The inherent conflict of interest in the Chinese tobacco control agency structure, which must meet commercial and public health objectives, undermined the introduction of new health warnings. To promote more effective tobacco control policies, the conflict of interest inhibiting the public health function of the State Tobacco Monopoly Administration (STMA) must be removed. Specifically, the public health function must be separated from oversight of commercial production, and packaging must be redesigned with pictorial warnings and messages compliant with Article 11 of the FCTC.

An examination of envy and jealousy in nursing academia.

PubMed

Cleary, Michelle; Walter, Garry; Halcomb, Elizabeth; Lopez, Violeta

2016-07-01

To discuss envy and jealousy and how their positive and negative aspects among nurse academics affect the workplace. In nursing academia, jealousy and envy are common emotions, engendered by demands for high productivity, intense competition for limited resources, preferences for particular assignments and opportunities for promotions. When these feelings are moderate and part of everyday rivalry, competition and ambition benefit the organisation. However, jealousy and envy can have serious consequences including damaged relationships and communication, and the undermining of colleagues' performance. Strategies are recommended to provide opportunities for self-reflection and consideration of how the workplace affects nursing academics' wellbeing and professional performance. Jealousy and envy can be damaging emotions in the workplace. The embittered, hostile person can undermine and damage relationships, disrupt teams and communication, and undermine organisational performance. Discussing the positive and negative effects of envy and jealousy provides an opportunity for nursing academics to self-reflect and to consider others and their own personal and professional performance. Understanding how jealousy and envy impact on the work environment, workplace relationships and individual/team performance is important especially for early career and seasoned nursing academics alike.

The compassionate sexist? How benevolent sexism promotes and undermines gender equality in the workplace.

PubMed

Hideg, Ivona; Ferris, D Lance

2016-11-01

Although sexist attitudes are generally thought to undermine support for employment equity (EE) policies supporting women, we argue that the effects of benevolent sexism are more complex. Across 4 studies, we extend the ambivalent sexism literature by examining both the positive and the negative effects benevolent sexism has for the support of gender-based EE policies. On the positive side, we show that individuals who endorse benevolent sexist attitudes on trait measures of sexism (Study 1) and individuals primed with benevolent sexist attitudes (Study 2) are more likely to support an EE policy, and that this effect is mediated by feelings of compassion. On the negative side, we find that this support extends only to EE policies that promote the hiring of women in feminine, and not in masculine, positions (Study 3 and 4). Thus, while benevolent sexism may appear to promote gender equality, it subtly undermines it by contributing to occupational gender segregation and leading to inaction in promoting women in positions in which they are underrepresented (i.e., masculine positions). (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Self-perceived Coparenting of Nonresident Fathers: Scale Development and Validation.

PubMed

Dyer, W Justin; Fagan, Jay; Kaufman, Rebecca; Pearson, Jessica; Cabrera, Natasha

2017-11-16

This study reports on the development and validation of the Fatherhood Research and Practice Network coparenting perceptions scale for nonresident fathers. Although other measures of coparenting have been developed, this is the first measure developed specifically for low-income, nonresident fathers. Focus groups were conducted to determine various aspects of coparenting. Based on this, a scale was created and administered to 542 nonresident fathers. Participants also responded to items used to examine convergent and predictive validity (i.e., parental responsibility, contact with the mother, father self-efficacy and satisfaction, child behavior problems, and contact and engagement with the child). Factor analyses and reliability tests revealed three distinct and reliable perceived coparenting factors: undermining, alliance, and gatekeeping. Validity tests suggest substantial overlap between the undermining and alliance factors, though undermining was uniquely related to child behavior problems. The alliance and gatekeeping factors showed strong convergent validity and evidence for predictive validity. Taken together, results suggest this relatively short measure (11 items) taps into three coparenting dimensions significantly predictive of aspects of individual and family life. © 2017 Family Process Institute.

Effects of optimism on creativity under approach and avoidance motivation

PubMed Central

Icekson, Tamar; Roskes, Marieke; Moran, Simone

2014-01-01

Focusing on avoiding failure or negative outcomes (avoidance motivation) can undermine creativity, due to cognitive (e.g., threat appraisals), affective (e.g., anxiety), and volitional processes (e.g., low intrinsic motivation). This can be problematic for people who are avoidance motivated by nature and in situations in which threats or potential losses are salient. Here, we review the relation between avoidance motivation and creativity, and the processes underlying this relation. We highlight the role of optimism as a potential remedy for the creativity undermining effects of avoidance motivation, due to its impact on the underlying processes. Optimism, expecting to succeed in achieving success or avoiding failure, may reduce negative effects of avoidance motivation, as it eases threat appraisals, anxiety, and disengagement—barriers playing a key role in undermining creativity. People experience these barriers more under avoidance than under approach motivation, and beneficial effects of optimism should therefore be more pronounced under avoidance than approach motivation. Moreover, due to their eagerness, approach motivated people may even be more prone to unrealistic over-optimism and its negative consequences. PMID:24616690

Cyber Deterrence and Stability

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

Goychayev, Rustam; Carr, Geoffrey A.; Weise, Rachel A.

Throughout the 20th and early 21st centuries, deterrence and arms control have been cornerstones of strategic stability between the superpowers. However, the weaponization of the cyber realm by State actors and the multipolar nature of cyber conflict now undermines that stability. Strategic stability is the state in which nations believe that if they act aggressively to undermine U.S. national interests and the post-World War II liberal democratic order, the consequences will outweigh the benefits. The sense of lawlessness and lack of consequences in the cyber realm embolden States to be more aggressive in taking actions that undermine stability. Accordingly, thismore » paper examines 1) the role of deterrence and arms control in securing cyber stability, and 2) the limitations and challenges associated with these traditional national security paradigms as applied to this emerging threat domain. This paper demonstrates that many 20th-century deterrence and arms control concepts are not particularly applicable in the cyber realm. However, they are not entirely irrelevant. The United States can distill lessons learned from this rich deterrence and arms control experience to develop and deploy a strategy to advance cyber stability.« less

Digital Speckle Photography of Subpixel Displacements of Speckle Structures Based on Analysis of Their Spatial Spectra

NASA Astrophysics Data System (ADS)

Maksimova, L. A.; Ryabukho, P. V.; Mysina, N. Yu.; Lyakin, D. V.; Ryabukho, V. P.

2018-04-01

We have investigated the capabilities of the method of digital speckle interferometry for determining subpixel displacements of a speckle structure formed by a displaceable or deformable object with a scattering surface. An analysis of spatial spectra of speckle structures makes it possible to perform measurements with a subpixel accuracy and to extend the lower boundary of the range of measurements of displacements of speckle structures to the range of subpixel values. The method is realized on the basis of digital recording of the images of undisplaced and displaced speckle structures, their spatial frequency analysis using numerically specified constant phase shifts, and correlation analysis of spatial spectra of speckle structures. Transformation into the frequency range makes it possible to obtain quantities to be measured with a subpixel accuracy from the shift of the interference-pattern minimum in the diffraction halo by introducing an additional phase shift into the complex spatial spectrum of the speckle structure or from the slope of the linear plot of the function of accumulated phase difference in the field of the complex spatial spectrum of the displaced speckle structure. The capabilities of the method have been investigated in natural experiment.

Spatial Query for Planetary Data

NASA Technical Reports Server (NTRS)

Shams, Khawaja S.; Crockett, Thomas M.; Powell, Mark W.; Joswig, Joseph C.; Fox, Jason M.

2011-01-01

Science investigators need to quickly and effectively assess past observations of specific locations on a planetary surface. This innovation involves a location-based search technology that was adapted and applied to planetary science data to support a spatial query capability for mission operations software. High-performance location-based searching requires the use of spatial data structures for database organization. Spatial data structures are designed to organize datasets based on their coordinates in a way that is optimized for location-based retrieval. The particular spatial data structure that was adapted for planetary data search is the R+ tree.

Cannibals in space: the coevolution of cannibalism and dispersal in spatially structured populations.

PubMed

Rudolf, Volker H W; Kamo, Masashi; Boots, Mike

2010-05-01

The propensity for cannibalism varies considerably both within and between species. Currently we have little understanding of both the causes of this variation and its evolutionary consequences for other life-history traits. We examine how different levels of spatial structure affect the evolution of cannibalism and how cannibalism in turn drives the evolution of dispersal. Using pair approximations and simulations, we show that cannibalism can easily evolve in spatially structured populations as long as some dispersal exists. Furthermore, for a wide range of intermediate levels of spatial structure, we find the possibility of evolutionary branching leading to polymorphism in cannibalism. We also show that cannibalism itself can have important evolutionary consequences and select for increased dispersal rates, thus helping to determine the spatial structure of populations. The coevolution of cannibalism and dispersal results in the evolution of various alternative life-history strategies with different dispersal and cannibalism regimes. Which strategy evolves depends on the environmental conditions that determine initial cannibalism rates. Our results therefore suggest that differences in spatial structure could explain variation in the propensity for cannibalism and cannibalistic polyphenism. Furthermore, results emphasize that cannibalism can drive the evolution of other life-history traits and determine the spatial structure of natural populations.

Workplace Wellness Programs: How Regulatory Flexibility Might Undermine Success

PubMed Central

2014-01-01

The Patient Protection and Affordable Care Act revised the law related to workplace wellness programs, which have become part of the nation’s broader health strategy. Health-contingent programs are required to be reasonably designed. However, the regulatory requirements are lax and might undermine program efficacy in terms of both health gains and financial return. I propose a method for the government to support a best-practices approach by considering an accreditation or certification process. Additionally I discuss the need for program evaluation and the potential for employers to be subject to litigation if programs are not carefully implemented. PMID:25211713

On spatial coalescents with multiple mergers in two dimensions.

PubMed

Heuer, Benjamin; Sturm, Anja

2013-08-01

We consider the genealogy of a sample of individuals taken from a spatially structured population when the variance of the offspring distribution is relatively large. The space is structured into discrete sites of a graph G. If the population size at each site is large, spatial coalescents with multiple mergers, so called spatial Λ-coalescents, for which ancestral lines migrate in space and coalesce according to some Λ-coalescent mechanism, are shown to be appropriate approximations to the genealogy of a sample of individuals. We then consider as the graph G the two dimensional torus with side length 2L+1 and show that as L tends to infinity, and time is rescaled appropriately, the partition structure of spatial Λ-coalescents of individuals sampled far enough apart converges to the partition structure of a non-spatial Kingman coalescent. From a biological point of view this means that in certain circumstances both the spatial structure as well as larger variances of the underlying offspring distribution are harder to detect from the sample. However, supplemental simulations show that for moderately large L the different structure is still evident. Copyright © 2012 Elsevier Inc. All rights reserved.

Exploring the Structure of Spatial Representations

PubMed Central

Madl, Tamas; Franklin, Stan; Chen, Ke; Trappl, Robert; Montaldi, Daniela

2016-01-01

It has been suggested that the map-like representations that support human spatial memory are fragmented into sub-maps with local reference frames, rather than being unitary and global. However, the principles underlying the structure of these ‘cognitive maps’ are not well understood. We propose that the structure of the representations of navigation space arises from clustering within individual psychological spaces, i.e. from a process that groups together objects that are close in these spaces. Building on the ideas of representational geometry and similarity-based representations in cognitive science, we formulate methods for learning dissimilarity functions (metrics) characterizing participants’ psychological spaces. We show that these learned metrics, together with a probabilistic model of clustering based on the Bayesian cognition paradigm, allow prediction of participants’ cognitive map structures in advance. Apart from insights into spatial representation learning in human cognition, these methods could facilitate novel computational tools capable of using human-like spatial concepts. We also compare several features influencing spatial memory structure, including spatial distance, visual similarity and functional similarity, and report strong correlations between these dimensions and the grouping probability in participants’ spatial representations, providing further support for clustering in spatial memory. PMID:27347681

Pathways towards instability in financial networks

NASA Astrophysics Data System (ADS)

Bardoscia, Marco; Battiston, Stefano; Caccioli, Fabio; Caldarelli, Guido

2017-02-01

Following the financial crisis of 2007-2008, a deep analogy between the origins of instability in financial systems and complex ecosystems has been pointed out: in both cases, topological features of network structures influence how easily distress can spread within the system. However, in financial network models, the details of how financial institutions interact typically play a decisive role, and a general understanding of precisely how network topology creates instability remains lacking. Here we show how processes that are widely believed to stabilize the financial system, that is, market integration and diversification, can actually drive it towards instability, as they contribute to create cyclical structures which tend to amplify financial distress, thereby undermining systemic stability and making large crises more likely. This result holds irrespective of the details of how institutions interact, showing that policy-relevant analysis of the factors affecting financial stability can be carried out while abstracting away from such details.

Pathways towards instability in financial networks

PubMed Central

Bardoscia, Marco; Battiston, Stefano; Caccioli, Fabio; Caldarelli, Guido

2017-01-01

Following the financial crisis of 2007–2008, a deep analogy between the origins of instability in financial systems and complex ecosystems has been pointed out: in both cases, topological features of network structures influence how easily distress can spread within the system. However, in financial network models, the details of how financial institutions interact typically play a decisive role, and a general understanding of precisely how network topology creates instability remains lacking. Here we show how processes that are widely believed to stabilize the financial system, that is, market integration and diversification, can actually drive it towards instability, as they contribute to create cyclical structures which tend to amplify financial distress, thereby undermining systemic stability and making large crises more likely. This result holds irrespective of the details of how institutions interact, showing that policy-relevant analysis of the factors affecting financial stability can be carried out while abstracting away from such details. PMID:28221338

Pathways towards instability in financial networks.

PubMed

Bardoscia, Marco; Battiston, Stefano; Caccioli, Fabio; Caldarelli, Guido

2017-02-21

Following the financial crisis of 2007-2008, a deep analogy between the origins of instability in financial systems and complex ecosystems has been pointed out: in both cases, topological features of network structures influence how easily distress can spread within the system. However, in financial network models, the details of how financial institutions interact typically play a decisive role, and a general understanding of precisely how network topology creates instability remains lacking. Here we show how processes that are widely believed to stabilize the financial system, that is, market integration and diversification, can actually drive it towards instability, as they contribute to create cyclical structures which tend to amplify financial distress, thereby undermining systemic stability and making large crises more likely. This result holds irrespective of the details of how institutions interact, showing that policy-relevant analysis of the factors affecting financial stability can be carried out while abstracting away from such details.

Advanced in In Situ Inspection of Automated Fiber Placement Systems

NASA Technical Reports Server (NTRS)

Juarez, Peter D.; Cramer, K. Elliott; Seebo, Jeffrey P.

2016-01-01

Automated Fiber Placement (AFP) systems have been developed to help take advantage of the tailorability of composite structures in aerospace applications. AFP systems allow the repeatable placement of uncured, spool fed, preimpregnated carbon fiber tape (tows) onto substrates in desired thicknesses and orientations. This automated process can incur defects, such as overlapping tow lines, which can severely undermine the structural integrity of the part. Current defect detection and abatement methods are very labor intensive, and still mostly rely on human manual inspection. Proposed is a thermographic in situ inspection technique which monitors tow placement with an on board thermal camera using the preheated substrate as a through transmission heat source. An investigation of the concept is conducted, and preliminary laboratory results are presented. Also included will be a brief overview of other emerging technologies that tackle the same issue. Keywords: Automated Fiber Placement, Manufacturing defects, Thermography

Spatial variation in the bacterial and denitrifying bacterial community in a biofilter treating subsurface agricultural drainage.

PubMed

Andrus, J Malia; Porter, Matthew D; Rodríguez, Luis F; Kuehlhorn, Timothy; Cooke, Richard A C; Zhang, Yuanhui; Kent, Angela D; Zilles, Julie L

2014-02-01

Denitrifying biofilters can remove agricultural nitrates from subsurface drainage, reducing nitrate pollution that contributes to coastal hypoxic zones. The performance and reliability of natural and engineered systems dependent upon microbially mediated processes, such as the denitrifying biofilters, can be affected by the spatial structure of their microbial communities. Furthermore, our understanding of the relationship between microbial community composition and function is influenced by the spatial distribution of samples.In this study we characterized the spatial structure of bacterial communities in a denitrifying biofilter in central Illinois. Bacterial communities were assessed using automated ribosomal intergenic spacer analysis for bacteria and terminal restriction fragment length polymorphism of nosZ for denitrifying bacteria.Non-metric multidimensional scaling and analysis of similarity (ANOSIM) analyses indicated that bacteria showed statistically significant spatial structure by depth and transect,while denitrifying bacteria did not exhibit significant spatial structure. For determination of spatial patterns, we developed a package of automated functions for the R statistical environment that allows directional analysis of microbial community composition data using either ANOSIM or Mantel statistics.Applying this package to the biofilter data, the flow path correlation range for the bacterial community was 6.4 m at the shallower, periodically in undated depth and 10.7 m at the deeper, continually submerged depth. These spatial structures suggest a strong influence of hydrology on the microbial community composition in these denitrifying biofilters. Understanding such spatial structure can also guide optimal sample collection strategies for microbial community analyses.

Insights from Modelling the Spatial Dependence Structure of Hydraulic Conductivity at the MADE Site Using Spatial Copulas

NASA Astrophysics Data System (ADS)

Haslauer, Claus; Bohling, Geoff

2013-04-01

Hydraulic conductivity (K) is a fundamental parameter that influences groundwater flow and solute transport. Measurements of K are limited and uncertain. Moreover, the spatial structure of K, which impacts the groundwater velocity field and hence directly influences the advective spreading of a solute migrating in the subsurface, is commonly described by approaches using second order moments. Spatial copulas have in the recent past been applied successfully to model the spatial dependence structure of heterogeneous subsurface datasets. At the MADE site, hydraulic conductivity (K) has been measured in exceptional detail. Two independently collected data-sets were used for this study: (1) ~2000 flowmeter based K measurements, and (2) ~20,000 direct-push based K measurements. These datasets exhibit a very heterogeneous (Var[ln(K)]>2) spatially distributed K field. A copula analysis reveals that the spatial dependence structure of the flowmeter and direct-push datasets are essentially the same. A spatial copula analysis factors out the influence of the marginal distribution of the property under investigation. This independence from the marginal distributions allows the copula analysis to reveal the underlying similarity between the spatial dependence structures of the flowmeter and direct-push datasets despite two complicating factors: 1) an overall offset between the datasets, with direct-push K values being, on average, roughly a factor of five lower than flowmeter K values, due at least in part to opposite biases between the two measurement techniques, and 2) the presence of some anomalously high K values in the direct-push dataset due to a lower limit on accurately measureable pressure responses in high-K zones. In addition, the vertical resolution of the direct-push dataset is ten times finer than that of the flowmeter dataset. Upscaling the direct-push data to compensate for this difference resulted in little change to the spatial structure. The objective of the presented work is to use multidimensional spatial copulas to describe and model the spatial dependence of the spatial structure of K at the heterogeneous MADE site, and evaluate the effects of this multidimensional description on solute transport.

Confronting Safety Gaps across Labor and Delivery Teams

PubMed Central

Maxfield, David G.; Lyndon, Audrey; Kennedy, Holly Powell; O’Keeffe, Dan; Zlatnik, Marya G.

2013-01-01

We assessed the occurrence of four safety concerns among labor and delivery teams: dangerous shortcuts, missing competencies, disrespect, and performance problems. 3282 participants completed surveys. 92% of physicians (906/985), 93% of midwives (385/414), and 98% of nurses (1846/1884) observed at least one concern within the preceding year. A majority of respondents said these concerns undermined patient safety, harmed patients, or led them to seriously consider transferring or leaving their positions. Only 9% of physicians, 13% of midwives, and 13% of nurses shared their full concerns with the person involved. Organizational silence is evident within labor and delivery teams. Improvement will require multiple strategies, employed at the personal, social, and structural levels. PMID:23871951

Effect of scanning velocity on femtosecond laser-induced periodic surface structures on HgCdTe crystal

NASA Astrophysics Data System (ADS)

Gu, Hongan; Dai, Ye; Wang, Haodong; Yan, Xiaona; Ma, Guohong

2017-12-01

In this paper, a femtosecond laser line-scanning irradiation was used to induce the periodic surface microstructure on HgCdTe crystal. Low spatial frequency laser induced periodic surface structures of 650-770 nm and high spatial frequency laser induced periodic surface structures of 152-246 nm were respectively found with different scanning speeds. The evolution process from low spatial frequency laser induced periodic surface structures to high spatial frequency laser induced periodic surface structures is characterized by scanning electron microscope. Their spatial periods deduced by using a two-dimensional Fourier transformation partly agree with the predictions of the Sipe-Drude theory. Confocal micro-Raman spectral show that the atomic arrangement of induced low spatial frequency laser-induced structures are basically consistent with the crystal in the central area of laser-scanning line, however a new peak at 164 cm-1 for the CdTe-like mode becomes evident due to the Hg vaporization when strong laser ablation happens. The obtained surface periodic ripples may have applications in fabricating advanced infrared detector.

Nonmonotonic spatial structure of interneuronal correlations in prefrontal microcircuits

PubMed Central

Safavi, Shervin; Dwarakanath, Abhilash; Kapoor, Vishal; Werner, Joachim; Hatsopoulos, Nicholas G.; Logothetis, Nikos K.; Panagiotaropoulos, Theofanis I.

2018-01-01

Correlated fluctuations of single neuron discharges, on a mesoscopic scale, decrease as a function of lateral distance in early sensory cortices, reflecting a rapid spatial decay of lateral connection probability and excitation. However, spatial periodicities in horizontal connectivity and associational input as well as an enhanced probability of lateral excitatory connections in the association cortex could theoretically result in nonmonotonic correlation structures. Here, we show such a spatially nonmonotonic correlation structure, characterized by significantly positive long-range correlations, in the inferior convexity of the macaque prefrontal cortex. This functional connectivity kernel was more pronounced during wakefulness than anesthesia and could be largely attributed to the spatial pattern of correlated variability between functionally similar neurons during structured visual stimulation. These results suggest that the spatial decay of lateral functional connectivity is not a common organizational principle of neocortical microcircuits. A nonmonotonic correlation structure could reflect a critical topological feature of prefrontal microcircuits, facilitating their role in integrative processes. PMID:29588415

Effects of geometrical structure on spatial distribution of thermal energy in two-dimensional triangular lattices

NASA Astrophysics Data System (ADS)

Liu, Yong-Yang; Xu, Yu-Liang; Liu, Zhong-Qiang; Li, Jing; Wang, Chun-Yang; Kong, Xiang-Mu

2018-07-01

Employing the correlation matrix technique, the spatial distribution of thermal energy in two-dimensional triangular lattices in equilibrium, interacting with linear springs, is studied. It is found that the spatial distribution of thermal energy varies with the included angle of the springs. In addition, the average thermal energy of the longer springs is lower. Springs with different included angle and length will lead to an inhomogeneous spatial distribution of thermal energy. This suggests that the spatial distribution of thermal energy is affected by the geometrical structure of the system: the more asymmetric the geometrical structure of the system is, the more inhomogeneous is the spatial distribution of thermal energy.

Deep inferior epigastric artery perforator flap donor-site closure with cannula-assisted, limited undermining, and progressive high-tension sutures versus standard abdominoplasty: complications, sensitivity, and cosmetic outcomes.

PubMed

Visconti, Giuseppe; Tomaselli, Federica; Monda, Anna; Barone-Adesi, Liliana; Salgarello, Marzia

2015-01-01

In deep inferior epigastric artery perforator (DIEP) flap breast reconstruction, abdominal donor-site cosmetic and sensibility outcomes and the closure technique have drawn little attention in the literature, with many surgeons still following the principles of standard abdominoplasty. In this article, the authors report their experience with the cannula-assisted, limited undermining, and progressive high-tension suture ("CALP") technique of DIEP donor-site closure compared with standard abdominoplasty. Between December of 2008 and January of 2013, 137 consecutive women underwent DIEP flap breast reconstruction. Of these, 82 patients (between December of 2008 and November of 2011) underwent DIEP flap donor-site closure by means of standard abdominoplasty (control group) and 55 patients (from December of 2011 to January of 2013) by means of cannula-assisted, limited undermining, and progressive high-tension suture (study group). The abdominal drainage daily output, donor-site complications, abdominal skin sensitivity at 1-year follow-up, cosmetic outcomes, and patient satisfaction were recorded and analyzed statistically. Daily drainage output was significantly lower in the study group. Donor-site complications were significantly higher in the control group (37.8 percent versus 9 percent). Seroma and wound healing problems were experienced in the control group. Abdominal skin sensibility was better preserved in the study group. Overall, abdominal wall aesthetic outcomes were similar in both groups, except for scar quality (better in the study group). According to the authors' experience, cannula-assisted, limited undermining, and progressive high-tension suture should be always preferred to standard abdominoplasty for DIEP donor-site closure to reduce the complication rate to improve abdominal skin sensitivity and scar quality. Therapeutic, II.

Evaluation of road failure vulnerability section through integrated geophysical and geotechnical studies

NASA Astrophysics Data System (ADS)

Adiat, K. A. N.; Akinlalu, A. A.; Adegoroye, A. A.

2017-06-01

In order to investigate the competence of the proposed road for pavement stability, geotechnical and geophysical investigations involving Land Magnetic, Very Low Frequency Electromagnetic (VLF-EM) and Electrical Resistivity methods were carried out along Akure-Ipinsa road Southwestern Nigeria. The magnetic profile was qualitatively and quantitatively interpreted to produce geomagnetic section that provides information on the basement topography and structural disposition beneath the proposed road. Similarly, the VLF-EM profile was equally interpreted to provide information on the possible occurrence of linear features beneath the study area. These linear features pose a potential risk to the proposed road as they are capable of undermining the stability of the pavement structure. The geoelectric parameters obtained from the quantitative interpretation of the VES data were used to generate geoelectric section. The geoelectric section generated shows that the study area was underlain by four geoelectric layers namely the topsoil, the weathered layer, the partly weathered/fractured basement and the fresh basement. The major part of the topsoil, which constitutes the subgrade, is characterized by relatively low resistivity values (<100 Ωm) suggestive of weak zones that are capable of undermining the stability of the proposed road. This therefore suggests that the layer is composed of incompetent materials that are unsuitable for engineering structures. Furthermore, fractured basement was also delineated beneath some portion of the proposed road. Since fracture is a weak zone, its presence can facilitate failure of the proposed road especially when it is occurring at shallow depth. The geotechnical results reveal that most of the investigated soil samples are clayey in nature. Integration of the results demonstrates that there is a good correlation between geophysical results and the geotechnical results. Furthermore, a vulnerability section that divided the road segments into three zones based on the degree of vulnerability was produced. These zones were high, moderate and low vulnerability zones. It is estimated that about 60% of the road segments constitutes moderate degree of vulnerability while 30% and 10% of the segments respectively constitute high and low degree of vulnerability.

Forest plunder in Southeast Asia: an environmental security nexus in Burma and Cambodia.

PubMed

Talbott, K; Brown, M

1998-01-01

This article discusses the cycle of conversion, consumption, and corruption that undermines the environment and civil society in Cambodia and Burma (Myanmar). In these countries, forests are declining in patterns similar to other Southeast Asian deforestation. Illegal logging, prostitution, and heroin trafficking constitute the bulk of Cambodia's shadow economy. Revenues are used to provide financial support for political causes and build the private wealth of the elite. Major political and guerilla groups and the Cambodian military have been major beneficiaries of logging revenue, supported private sector forestry in many military zones, and facilitated logging and trade. About 40% of land goes to forest concessions granted to Southeast Asian companies, and revenues bypass the regular state budget. In Burma, the cease fire agreements in the early 1990s, led to remote border area forests being opened up to large, nonsustainable commercial timber mining. Land was divided into ethnic and government controlled areas. Timber profits were funneled into a business owned by members of the new ruling force, the SLORC, and used to launder drug exports and profits. Trading partners include Thailand, and most recently, China. It is speculated that deforested areas are replanted with opium poppies, and trade routes carry timber and heroin. The unregulated logging industry and the lack of financial accounting of the timber trade undermine the structures of civil society and good governance. Forest policies appear progressive but are in reality unenforced. Politics and agreements in both countries are closely tied to deforestation issues.

Psychiatric Genomics and Mental Health Treatment: Setting the Ethical Agenda.

PubMed

Kong, Camillia; Dunn, Michael; Parker, Michael

2017-04-01

Realizing the benefits of translating psychiatric genomics research into mental health care is not straightforward. The translation process gives rise to ethical challenges that are distinctive from challenges posed within psychiatric genomics research itself, or that form part of the delivery of clinical psychiatric genetics services. This article outlines and considers three distinct ethical concerns posed by the process of translating genomic research into frontline psychiatric practice and policy making. First, the genetic essentialism that is commonly associated with the genomics revolution in health care might inadvertently exacerbate stigma towards people with mental disorders. Secondly, the promises of genomic medicine advance a narrative of individual empowerment. This narrative could promote a fatalism towards patients' biology in ways that function in practice to undermine patients' agency and autonomy, or, alternatively, a heightened sense of subjective genetic responsibility could become embedded within mental health services that leads to psychosocial therapeutic approaches and the clinician-patient therapeutic alliance being undermined. Finally, adopting a genomics-focused approach to public mental health risks shifting attention away from the complex causal relationships between inequitable socio-economic, political, and cultural structures and negative mental health outcomes. The article concludes by outlining a number of potential pathways for future ethics research that emphasizes the importance of examining appropriate translation mechanisms, the complementarity between genetic and psychosocial models of mental disorder, the implications of genomic information for the clinician-patient relationship, and funding priorities and resource allocation decision making in mental health.

Staff personhood in dementia care settings: "Do they care about me?"

PubMed

Cooke, Heather A

2018-06-01

This article aims to examine RCAs' own experiences of personhood in dementia care settings. Conceptually, person-centred care entails fostering the personhood of residents and the residential care aides (RCAs) who provide much of their hands-on care. To date, however, staff personhood has been overlooked in the empirical literature. The study was part of a larger focused ethnographic project exploring how the organisational care environment impedes or facilitates the provision of quality dementia care. Semi-structured interviews with 23 RCAs and more than 230 hours of participant observation were conducted in two nursing homes with specialised dementia units in British Columbia, Canada. Two overarching themes, "personhood undermined-management-staff relations" and "personhood undermined-workplace policies and practices" emerged, illustrating how, despite exposure to features believed beneficial to their working environment (e.g., favourable staffing ratios, relatively good remuneration), RCAs encountered repeated affronts to their personhood. The first theme encompasses the importance of being known (i.e., as persons and of their job demands) and valued (i.e., appreciated for their work in non-monetary terms). The second highlights the salience of work-life balance, full-staffing coverage and supportive human resource practices. RCAs' experiences reveal how the ongoing search for cost-efficiencies, cost-containment and cost-accountability overshadows their individuality, indicating a key disconnect between conceptual ideals and workplace realities. Organisations are encouraged to consider creating person-centred management and workplace practices that provide tangible evidence that RCAs, and their work, matter. © 2018 John Wiley & Sons Ltd.

Spatio-Temporal Structure, Path Characteristics, and Perceptual Grouping in Immediate Serial Spatial Recall

PubMed Central

De Lillo, Carlo; Kirby, Melissa; Poole, Daniel

2016-01-01

Immediate serial spatial recall measures the ability to retain sequences of locations in short-term memory and is considered the spatial equivalent of digit span. It is tested by requiring participants to reproduce sequences of movements performed by an experimenter or displayed on a monitor. Different organizational factors dramatically affect serial spatial recall but they are often confounded or underspecified. Untangling them is crucial for the characterization of working-memory models and for establishing the contribution of structure and memory capacity to spatial span. We report five experiments assessing the relative role and independence of factors that have been reported in the literature. Experiment 1 disentangled the effects of spatial clustering and path-length by manipulating the distance of items displayed on a touchscreen monitor. Long-path sequences segregated by spatial clusters were compared with short-path sequences not segregated by clusters. Recall was more accurate for sequences segregated by clusters independently from path-length. Experiment 2 featured conditions where temporal pauses were introduced between or within cluster boundaries during the presentation of sequences with the same paths. Thus, the temporal structure of the sequences was either consistent or inconsistent with a hierarchical representation based on segmentation by spatial clusters but the effect of structure could not be confounded with effects of path-characteristics. Pauses at cluster boundaries yielded more accurate recall, as predicted by a hierarchical model. In Experiment 3, the systematic manipulation of sequence structure, path-length, and presence of path-crossings of sequences showed that structure explained most of the variance, followed by the presence/absence of path-crossings, and path-length. Experiments 4 and 5 replicated the results of the previous experiments in immersive virtual reality navigation tasks where the viewpoint of the observer changed dynamically during encoding and recall. This suggested that the effects of structure in spatial span are not dependent on perceptual grouping processes induced by the aerial view of the stimulus array typically afforded by spatial recall tasks. These results demonstrate the independence of coding strategies based on structure from effects of path characteristics and perceptual grouping in immediate serial spatial recall. PMID:27891101

Advanced data structures for the interpretation of image and cartographic data in geo-based information systems

NASA Technical Reports Server (NTRS)

Peuquet, D. J.

1986-01-01

A growing need to usse geographic information systems (GIS) to improve the flexibility and overall performance of very large, heterogeneous data bases was examined. The Vaster structure and the Topological Grid structure were compared to test whether such hybrid structures represent an improvement in performance. The use of artificial intelligence in a geographic/earth sciences data base context is being explored. The architecture of the Knowledge Based GIS (KBGIS) has a dual object/spatial data base and a three tier hierarchial search subsystem. Quadtree Spatial Spectra (QTSS) are derived, based on the quadtree data structure, to generate and represent spatial distribution information for large volumes of spatial data.

Spatial structure and electronic spectrum of TiSi{/n -} clusters ( n = 6-18)

NASA Astrophysics Data System (ADS)

Borshch, N. A.; Pereslavtseva, N. S.; Kurganskii, S. I.

2014-10-01

Results from optimizing the spatial structure and calculated electronic spectra of anion clusters TiSi{/n -} ( n = 6-18) are presented. Calculations are performed within the density functional theory. Spatial structures of clusters detected experimentally are established by comparing the calculated and experimental data. It is shown that prismatic and fullerene-like structures are the ones most energetically favorable for clusters TiSi{/n -}. It is concluded that these structures are basic when building clusters with close numbers of silicon atoms.

Rectangular Array Model Supporting Students' Spatial Structuring in Learning Multiplication

ERIC Educational Resources Information Center

Shanty, Nenden Octavarulia; Wijaya, Surya

2012-01-01

We examine how rectangular array model can support students' spatial structuring in learning multiplication. To begin, we define what we mean by spatial structuring as the mental operation of constructing an organization or form for an object or set of objects. For that reason, the eggs problem was chosen as the starting point in which the…

How a Spatial Arrangement of Secondary Structure Elements Is Dispersed in the Universe of Protein Folds

PubMed Central

Minami, Shintaro; Sawada, Kengo; Chikenji, George

2014-01-01

It has been known that topologically different proteins of the same class sometimes share the same spatial arrangement of secondary structure elements (SSEs). However, the frequency by which topologically different structures share the same spatial arrangement of SSEs is unclear. It is important to estimate this frequency because it provides both a deeper understanding of the geometry of protein folds and a valuable suggestion for predicting protein structures with novel folds. Here we clarified the frequency with which protein folds share the same SSE packing arrangement with other folds, the types of spatial arrangement of SSEs that are frequently observed across different folds, and the diversity of protein folds that share the same spatial arrangement of SSEs with a given fold, using a protein structure alignment program MICAN, which we have been developing. By performing comprehensive structural comparison of SCOP fold representatives, we found that approximately 80% of protein folds share the same spatial arrangement of SSEs with other folds. We also observed that many protein pairs that share the same spatial arrangement of SSEs belong to the different classes, often with an opposing N- to C-terminal direction of the polypeptide chain. The most frequently observed spatial arrangement of SSEs was the 2-layer α/β packing arrangement and it was dispersed among as many as 27% of SCOP fold representatives. These results suggest that the same spatial arrangements of SSEs are adopted by a wide variety of different folds and that the spatial arrangement of SSEs is highly robust against the N- to C-terminal direction of the polypeptide chain. PMID:25243952

GSHR-Tree: a spatial index tree based on dynamic spatial slot and hash table in grid environments

NASA Astrophysics Data System (ADS)

Chen, Zhanlong; Wu, Xin-cai; Wu, Liang

2008-12-01

Computation Grids enable the coordinated sharing of large-scale distributed heterogeneous computing resources that can be used to solve computationally intensive problems in science, engineering, and commerce. Grid spatial applications are made possible by high-speed networks and a new generation of Grid middleware that resides between networks and traditional GIS applications. The integration of the multi-sources and heterogeneous spatial information and the management of the distributed spatial resources and the sharing and cooperative of the spatial data and Grid services are the key problems to resolve in the development of the Grid GIS. The performance of the spatial index mechanism is the key technology of the Grid GIS and spatial database affects the holistic performance of the GIS in Grid Environments. In order to improve the efficiency of parallel processing of a spatial mass data under the distributed parallel computing grid environment, this paper presents a new grid slot hash parallel spatial index GSHR-Tree structure established in the parallel spatial indexing mechanism. Based on the hash table and dynamic spatial slot, this paper has improved the structure of the classical parallel R tree index. The GSHR-Tree index makes full use of the good qualities of R-Tree and hash data structure. This paper has constructed a new parallel spatial index that can meet the needs of parallel grid computing about the magnanimous spatial data in the distributed network. This arithmetic splits space in to multi-slots by multiplying and reverting and maps these slots to sites in distributed and parallel system. Each sites constructs the spatial objects in its spatial slot into an R tree. On the basis of this tree structure, the index data was distributed among multiple nodes in the grid networks by using large node R-tree method. The unbalance during process can be quickly adjusted by means of a dynamical adjusting algorithm. This tree structure has considered the distributed operation, reduplication operation transfer operation of spatial index in the grid environment. The design of GSHR-Tree has ensured the performance of the load balance in the parallel computation. This tree structure is fit for the parallel process of the spatial information in the distributed network environments. Instead of spatial object's recursive comparison where original R tree has been used, the algorithm builds the spatial index by applying binary code operation in which computer runs more efficiently, and extended dynamic hash code for bit comparison. In GSHR-Tree, a new server is assigned to the network whenever a split of a full node is required. We describe a more flexible allocation protocol which copes with a temporary shortage of storage resources. It uses a distributed balanced binary spatial tree that scales with insertions to potentially any number of storage servers through splits of the overloaded ones. The application manipulates the GSHR-Tree structure from a node in the grid environment. The node addresses the tree through its image that the splits can make outdated. This may generate addressing errors, solved by the forwarding among the servers. In this paper, a spatial index data distribution algorithm that limits the number of servers has been proposed. We improve the storage utilization at the cost of additional messages. The structure of GSHR-Tree is believed that the scheme of this grid spatial index should fit the needs of new applications using endlessly larger sets of spatial data. Our proposal constitutes a flexible storage allocation method for a distributed spatial index. The insertion policy can be tuned dynamically to cope with periods of storage shortage. In such cases storage balancing should be favored for better space utilization, at the price of extra message exchanges between servers. This structure makes a compromise in the updating of the duplicated index and the transformation of the spatial index data. Meeting the needs of the grid computing, GSHRTree has a flexible structure in order to satisfy new needs in the future. The GSHR-Tree provides the R-tree capabilities for large spatial datasets stored over interconnected servers. The analysis, including the experiments, confirmed the efficiency of our design choices. The scheme should fit the needs of new applications of spatial data, using endlessly larger datasets. Using the system response time of the parallel processing of spatial scope query algorithm as the performance evaluation factor, According to the result of the simulated the experiments, GSHR-Tree is performed to prove the reasonable design and the high performance of the indexing structure that the paper presented.

A Correlational Study of Seven Projective Spatial Structures with Regard to the Phases of the MOON^

NASA Astrophysics Data System (ADS)

Wellner, Karen Linette

1995-01-01

This study investigated the relationship between projective spatial structures and the ability to construct a scientific model. In addition, gender-related performance and the influence of prior astronomy experience on task success were evaluated. Sixty-one college science undergraduates were individually administered Piagetian tasks to assess for projective spatial structures and the ability to set up a phases of the moon model. The spatial tasks included: (a) Mountains task (coordination of perspectives); (b) Railroad task (size and intervals of objects with increasing distance); (c) Telephone Poles task (masking and ordering objects); and (d) Shadows task (spatial relationships between an object and its shadow, dependent upon the object's orientation). Cramer coefficient analyses indicated that significant relationships existed between Moon task and spatial task success. In particular, the Shadows task, requiring subjects to draw shadows of objects in different orientations, proved most difficult and was most strongly associated with with a subject's understanding of lunar phases. Chi-square tests for two independent samples were used to analyze gender performance differences on each of the Ave tasks. Males performed significantly better at a.05 significance level in regard to the Shadows task and the Moon task. Chi-square tests for two independent samples showed no significant difference in Moon task performance between subjects with astronomy or Earth science coursework, and those without such science classroom experience. Overall, only six subjects passed all seven projective spatial structure tasks. Piaget (1967) contends that concrete -operational spatial structures must be established before an individual is able to develop formal-operational patterns of thinking. The results of this study indicate that 90% of the interviewed science majors are still operating at the concrete-operational level. Several educational implications were drawn from this study: (1) The teaching of spatially dependent content to students without prerequisite spatial structures results in understanding no further beyond that which can be memorized; (2) assessment for projective spatial structures should precede science lessons dealing with time-space relationships, and (3) a student's level of spatial ability may directly impact upon interpretation of three-dimensional models.

The effect of spatially variable overstory on the understory light environment of an open-canopied longleaf pine forest

Treesearch

Michael A. Battaglia; Pu Mou; Brian Palik; Robert J. Mitchell

2002-01-01

Spatial aggregation of forest structure strongly regulates understory light and its spatial variation in longleaf pine (Pinus palustris Mill.) forest ecosystems. Previous studies have demonstrated that light availability strongly influences longleaf pine seedling growth. In this study, the relationship between spatial structure of a longleaf pine...

NHS market liberalisation and the TTIP agreement.

PubMed

Regan, Paul; Ball, Elaine

2016-07-01

Governments over the past three decades have undermined the founding principles of the NHS through reforms and market liberalisation. With greater involvement of commercial interests in health care, the NHS will become less democratic and transparent. Recent reforms, which were intended to improve productivity, quality and cost efficiency, have left the NHS exposed to the unwieldy model of market liberalisation and the attrition of public health care. The role of community nurses has been particularly destabilised by commissioning, as their work is difficult to measure. The advent of the Transatlantic Trade and Investment Partnership could further undermine the NHS to the benefit of international commercial interests.

Time pressure undermines performance more under avoidance than approach motivation.

PubMed

Roskes, Marieke; Elliot, Andrew J; Nijstad, Bernard A; De Dreu, Carsten K W

2013-06-01

Four experiments were designed to test the hypothesis that performance is particularly undermined by time pressure when people are avoidance motivated. The results supported this hypothesis across three different types of tasks, including those well suited and those ill suited to the type of information processing evoked by avoidance motivation. We did not find evidence that stress-related emotions were responsible for the observed effect. Avoidance motivation is certainly necessary and valuable in the self-regulation of everyday behavior. However, our results suggest that given its nature and implications, it seems best that avoidance motivation is avoided in situations that involve (time) pressure.

Temporal prediction restores the evaluative processing of delayed action feedback: an electrophysiological study.

PubMed

Kimura, Kenta; Kimura, Motohiro

2016-09-28

The evaluative processing of the valence of action feedback is reflected by an event-related brain potential component called feedback-related negativity (FRN) or reward positivity (RewP). Recent studies have shown that FRN/RewP is markedly reduced when the action-feedback interval is long (e.g. 6000 ms), indicating that an increase in the action-feedback interval can undermine the evaluative processing of the valence of action feedback. The aim of the present study was to investigate whether or not such undermined evaluative processing of delayed action feedback could be restored by improving the accuracy of the prediction in terms of the timing of action feedback. With a typical gambling task in which the participant chose one of two cards and received an action feedback indicating monetary gain or loss, the present study showed that FRN/RewP was significantly elicited even when the action-feedback interval was 6000 ms, when an auditory stimulus sequence was additionally presented during the action-feedback interval as a temporal cue. This result suggests that the undermined evaluative processing of delayed action feedback can be restored by increasing the accuracy of the prediction on the timing of the action feedback.

SPA face lift: SMAS plication-anchoring.

PubMed

Mottura, A Aldo

2011-08-01

A variation of the superficial musculoaponeurotic system (SMAS) plication called SPA face lift is here described. An axial line and then two medial and lateral parallel lines are penciled on the skin from the lateral canthus to the earlobe to show the future plication area. The undermining zone is delimited 1 cm beyond the medial line. In face- and neck-lifting, such marks extend vertically to the neck. Once the skin is undermined up to the delimiting marks, the three lines are penciled again on the fat layer, and a running lock suture is used for plication, with big superficial bites between the two distal lines. In fatty faces, a strip of fat is removed along the axial line to avoid bulging that can be seen through the skin. Because the undermining is limited, minor swelling occurs, and the postoperative recovery is shorter and faster. The same three lines can be marked in the contralateral side or can differ in cases of asymmetry. This report describes 244 face-lifts without any facial nerve problems. The author managed five hematoma cases in which surgery to the neck was performed. Three patients had to be touched up for insufficient skin tension. The SPA technique is consistent and easy to learn.

Reflexive convention: civil partnership, marriage and family.

PubMed

Heaphy, Brian

2017-09-14

Drawing on an analysis of qualitative interview data from a study of formalized same-sex relationships (civil partnerships) this paper examines the enduring significance of marriage and family as social institutions. In doing so, it intervenes in current debates in the sociology of family and personal life about how such institutions are undermined by reflexivity or bolstered by convention. Against the backdrop of dominating sociological frames for understanding the links between the changing nature of marriage and family and same-sex relationship recognition, the paper analyses the diverse and overlapping ways (including the simple, relational, strategic, ambivalent and critical ways) in which same-sex partners reflexively constructed and engaged with marriage and family conventions. My analysis suggests that instead of viewing reflexivity and convention as mutually undermining, as some sociologists of family and personal life do, it is insightful to explore how diverse forms of reflexivity and convention interact in everyday life to reconfigure the social institutions of marriage and family, but do not undermine them as such. I argue the case for recognizing the ways in which 'reflexive convention', or reflexive investment in convention, contributes to the continuing significance of marriage and family as social institutions. © London School of Economics and Political Science 2017.

The dark side of monetary incentive: how does extrinsic reward crowd out intrinsic motivation.

PubMed

Ma, Qingguo; Jin, Jia; Meng, Liang; Shen, Qiang

2014-02-12

It was widely believed that incentives could effectively enhance the motivation of both students and employees. However, psychologists reported that extrinsic reward actually could undermine individuals' intrinsic motivation to a given interesting task, which challenged viewpoints from traditional incentive theories. Numerous studies have been carried out to test and explain the undermining effect; however, the neural basis of this effect is still elusive. Here, we carried out an electrophysiological study with a simple but interesting stopwatch task to explore to what extent the performance-based monetary reward undermines individuals' intrinsic motivation toward the task. The electrophysiological data showed that the differentiated feedback-related negativity amplitude toward intrinsic success failure divergence was prominently reduced once the extrinsic reward was imposed beforehand. However, such a difference was not observed in the control group, in which no extrinsic reward was provided throughout the experiment. Furthermore, such a pattern was not observed for P300 amplitude. Therefore, the current results indicate that extrinsic reward demotivates the intrinsic response of individuals toward success-failure outcome, which was reflected in the corresponding reduced motivational-related differentiated feedback-related negativity, but not in amplitude of P300.

Hospital physician payment mechanisms in Austria: do they provide gateways to institutional corruption?

PubMed

Sommersguter-Reichmann, Margit; Stepan, Adolf

2017-12-01

Institutional corruption in the health care sector has gained considerable attention during recent years, as it acknowledges the fact that service providers who are acting in accordance with the institutional and environmental settings can nevertheless undermine a health care system's purposes as a result of the (financial) conflicts of interest to which the service providers are exposed. The present analysis aims to contribute to the examination of institutional corruption in the health sector by analyzing whether the current payment mechanism of separately remunerating salaried hospital physicians for treating supplementary insured patients in public hospitals, in combination with the public hospital physician's possibility of taking up dual practice as a self-employed physician with a private practice and/or as an attending physician in private hospitals, has the potential to undermine the primary purposes of the Austrian public health care system. Based on the analysis of the institutional design of the Austrian public hospital sector, legal provisions and directives have been identified, which have the potential to promote conduct on the part of the public hospital physician that systematically undermines the achievement of the Austrian public health system's primary purposes.

Single-molecule RNA detection at depth by hybridization chain reaction and tissue hydrogel embedding and clearing.

PubMed

Shah, Sheel; Lubeck, Eric; Schwarzkopf, Maayan; He, Ting-Fang; Greenbaum, Alon; Sohn, Chang Ho; Lignell, Antti; Choi, Harry M T; Gradinaru, Viviana; Pierce, Niles A; Cai, Long

2016-08-01

Accurate and robust detection of mRNA molecules in thick tissue samples can reveal gene expression patterns in single cells within their native environment. Preserving spatial relationships while accessing the transcriptome of selected cells is a crucial feature for advancing many biological areas - from developmental biology to neuroscience. However, because of the high autofluorescence background of many tissue samples, it is difficult to detect single-molecule fluorescence in situ hybridization (smFISH) signals robustly in opaque thick samples. Here, we draw on principles from the emerging discipline of dynamic nucleic acid nanotechnology to develop a robust method for multi-color, multi-RNA imaging in deep tissues using single-molecule hybridization chain reaction (smHCR). Using this approach, single transcripts can be imaged using epifluorescence, confocal or selective plane illumination microscopy (SPIM) depending on the imaging depth required. We show that smHCR has high sensitivity in detecting mRNAs in cell culture and whole-mount zebrafish embryos, and that combined with SPIM and PACT (passive CLARITY technique) tissue hydrogel embedding and clearing, smHCR can detect single mRNAs deep within thick (0.5 mm) brain slices. By simultaneously achieving ∼20-fold signal amplification and diffraction-limited spatial resolution, smHCR offers a robust and versatile approach for detecting single mRNAs in situ, including in thick tissues where high background undermines the performance of unamplified smFISH. © 2016. Published by The Company of Biologists Ltd.

Implications of between-isolate variation for climate change impact modelling of Haemonchus contortus populations.

PubMed

Rose Vineer, H; Steiner, J; Knapp-Lawitzke, F; Bull, K; von Son-de Fernex, E; Bosco, A; Hertzberg, H; Demeler, J; Rinaldi, L; Morrison, A A; Skuce, P; Bartley, D J; Morgan, E R

2016-10-15

The impact of climate change on parasites and parasitic diseases is a growing concern and numerous empirical and mechanistic models have been developed to predict climate-driven spatial and temporal changes in the distribution of parasites and disease risk. Variation in parasite phenotype and life-history traits between isolates could undermine the application of such models at broad spatial scales. Seasonal variation in the transmission of the haematophagous gastrointestinal nematode Haemonchus contortus, one of the most pathogenic helminth species infecting sheep and goats worldwide, is primarily determined by the impact of environmental conditions on the free-living stages. To evaluate variability in the development success and mortality of the free-living stages of H. contortus and the impact of this variability on future climate impact modelling, three isolates of diverse origin were cultured at a range of temperatures between 15°C and 37°C to determine their development success compared with simulations using the GLOWORM-FL H. contortus model. No significant difference was observed in the developmental success of the three isolates of H. contortus tested, nor between isolates and model simulations. However, development success of all isolates at 37°C was lower than predicted by the model, suggesting the potential for overestimation of transmission risk at higher temperatures, such as those predicted under some scenarios of climate change. Recommendations are made for future climate impact modelling of gastrointestinal nematodes. Copyright © 2016 Elsevier B.V. All rights reserved.

Consultancy research as a barrier to strengthening social science research capacity in Uganda.

PubMed

Wight, Daniel; Ahikire, Josephine; Kwesiga, Joy C

2014-09-01

There is a shortage of senior African social scientists available to lead or manage research in Africa, undermining the continent's ability to interpret and solve its socio-economic and public health problems. This is despite decades of investment to strengthen research capacity. This study investigated the role of individually commissioned consultancy research in this lack of capacity. In 2006 structured interviews (N = 95) and two group discussions (N = 16 total) were conducted with a fairly representative sample of Ugandan academic social scientists from four universities. Twenty-four senior members of 22 Ugandan and international commissioning organizations were interviewed. Eight key actors were interviewed in greater depth. Much of Ugandan social science research appears to take the form of small, individually contracted consultancy projects. Researchers perceived this to constrain their professional development and, more broadly, social science research capacity across Uganda. Conversely, most research commissioners seemed broadly satisfied with the research expertise available and felt no responsibility to contribute to strengthening research capacity. Most consultancy research does not involve institutional overheads and there seems little awareness of, or interest in, such overheads. Although inequalities in the global knowledge economy are probably perpetuated primarily by macro-level factors, in line with Dependency Theory, meso-level factors are also important. The current research market and institutional structures in Uganda appear to create career paths that seriously impede the development of high quality social science research capacity, undermining donor investments and professional effort to strengthen this capacity. These problems are probably generic to much of sub-Saharan Africa. However, both commissioning and research organizations seem ready, in principle, to establish national guidelines for institutional research consultancies. These could develop both institutional and individual research capacity, improve output and accountability, and facilitate academic research funding and indigenous research agendas. Copyright © 2014. Published by Elsevier Ltd.

Structural Model Error and Decision Relevancy

NASA Astrophysics Data System (ADS)

Goldsby, M.; Lusk, G.

2017-12-01

The extent to which climate models can underwrite specific climate policies has long been a contentious issue. Skeptics frequently deny that climate models are trustworthy in an attempt to undermine climate action, whereas policy makers often desire information that exceeds the capabilities of extant models. While not skeptics, a group of mathematicians and philosophers [Frigg et al. (2014)] recently argued that even tiny differences between the structure of a complex dynamical model and its target system can lead to dramatic predictive errors, possibly resulting in disastrous consequences when policy decisions are based upon those predictions. They call this result the Hawkmoth effect (HME), and seemingly use it to rebuke rightwing proposals to forgo mitigation in favor of adaptation. However, a vigorous debate has emerged between Frigg et al. on one side and another philosopher-mathematician pair [Winsberg and Goodwin (2016)] on the other. On one hand, Frigg et al. argue that their result shifts the burden to climate scientists to demonstrate that their models do not fall prey to the HME. On the other hand, Winsberg and Goodwin suggest that arguments like those asserted by Frigg et al. can be, if taken seriously, "dangerous": they fail to consider the variety of purposes for which models can be used, and thus too hastily undermine large swaths of climate science. They put the burden back on Frigg et al. to show their result has any effect on climate science. This paper seeks to attenuate this debate by establishing an irenic middle position; we find that there is more agreement between sides than it first seems. We distinguish a `decision standard' from a `burden of proof', which helps clarify the contributions to the debate from both sides. In making this distinction, we argue that scientists bear the burden of assessing the consequences of HME, but that the standard Frigg et al. adopt for decision relevancy is too strict.

Active marks structure optimization for optical-electronic systems of spatial position control of industrial objects

NASA Astrophysics Data System (ADS)

Sycheva, Elena A.; Vasilev, Aleksandr S.; Lashmanov, Oleg U.; Korotaev, Valery V.

2017-06-01

The article is devoted to the optimization of optoelectronic systems of the spatial position of objects. Probabilistic characteristics of the detection of an active structured mark on a random noisy background are investigated. The developed computer model and the results of the study allow us to estimate the probabilistic characteristics of detection of a complex structured mark on a random gradient background, and estimate the error of spatial coordinates. The results of the study make it possible to improve the accuracy of measuring the coordinates of the object. Based on the research recommendations are given on the choice of parameters of the optimal mark structure for use in opticalelectronic systems for monitoring the spatial position of large-sized structures.

The spatial structure of chronic morbidity: evidence from UK census returns.

PubMed

Dutey-Magni, Peter F; Moon, Graham

2016-08-24

Disease prevalence models have been widely used to estimate health, lifestyle and disability characteristics for small geographical units when other data are not available. Yet, knowledge is often lacking about how to make informed decisions around the specification of such models, especially regarding spatial assumptions placed on their covariance structure. This paper is concerned with understanding processes of spatial dependency in unexplained variation in chronic morbidity. 2011 UK census data on limiting long-term illness (LLTI) is used to look at the spatial structure in chronic morbidity across England and Wales. The variance and spatial clustering of the odds of LLTI across local authority districts (LADs) and middle layer super output areas are measured across 40 demographic cross-classifications. A series of adjacency matrices based on distance, contiguity and migration flows are tested to examine the spatial structure in LLTI. Odds are then modelled using a logistic mixed model to examine the association with district-level covariates and their predictive power. The odds of chronic illness are more dispersed than local age characteristics, mortality, hospitalisation rates and chance alone would suggest. Of all adjacency matrices, the three-nearest neighbour method is identified as the best fitting. Migration flows can also be used to construct spatial weights matrices which uncover non-negligible autocorrelation. Once the most important characteristics observable at the LAD-level are taken into account, substantial spatial autocorrelation remains which can be modelled explicitly to improve disease prevalence predictions. Systematic investigation of spatial structures and dependency is important to develop model-based estimation tools in chronic disease mapping. Spatial structures reflecting migration interactions are easy to develop and capture autocorrelation in LLTI. Patterns of spatial dependency in the geographical distribution of LLTI are not comparable across ethnic groups. Ethnic stratification of local health information is needed and there is potential to further address complexity in prevalence models by improving access to disaggregated data.

Local topography shapes fine-scale spatial genetic structure in the Arkansas Valley evening primrose, Oenothera harringtonii (Onagraceae).

PubMed

Rhodes, Matthew K; Fant, Jeremie B; Skogen, Krissa A

2014-01-01

Identifying factors that shape the spatial distribution of genetic variation is crucial to understanding many population- and landscape-level processes. In this study, we explore fine-scale spatial genetic structure in Oenothera harringtonii (Onagraceae), an insect-pollinated, gravity-dispersed herb endemic to the grasslands of south-central and southeastern Colorado, USA. We genotyped 315 individuals with 11 microsatellite markers and utilized a combination of spatial autocorrelation analyses and landscape genetic models to relate life history traits and landscape features to dispersal processes. Spatial genetic structure was consistent with theoretical expectations of isolation by distance, but this pattern was weak (Sp = 0.00374). Anisotropic analyses indicated that spatial genetic structure was markedly directional, in this case consistent with increased dispersal along prominent slopes. Landscape genetic models subsequently confirmed that spatial genetic variation was significantly influenced by local topographic heterogeneity, specifically that geographic distance, elevation and aspect were important predictors of spatial genetic structure. Among these variables, geographic distance was ~68% more important than elevation in describing spatial genetic variation, and elevation was ~42% more important than aspect after removing the effect of geographic distance. From these results, we infer a mechanism of hydrochorous seed dispersal along major drainages aided by seasonal monsoon rains. Our findings suggest that landscape features may shape microevolutionary processes at much finer spatial scales than typically considered, and stress the importance of considering how particular dispersal vectors are influenced by their environmental context. © The American Genetic Association 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Shade tree spatial structure and pod production explain frosty pod rot intensity in cacao agroforests, Costa Rica.

PubMed

Gidoin, Cynthia; Avelino, Jacques; Deheuvels, Olivier; Cilas, Christian; Bieng, Marie Ange Ngo

2014-03-01

Vegetation composition and plant spatial structure affect disease intensity through resource and microclimatic variation effects. The aim of this study was to evaluate the independent effect and relative importance of host composition and plant spatial structure variables in explaining disease intensity at the plot scale. For that purpose, frosty pod rot intensity, a disease caused by Moniliophthora roreri on cacao pods, was monitored in 36 cacao agroforests in Costa Rica in order to assess the vegetation composition and spatial structure variables conducive to the disease. Hierarchical partitioning was used to identify the most causal factors. Firstly, pod production, cacao tree density and shade tree spatial structure had significant independent effects on disease intensity. In our case study, the amount of susceptible tissue was the most relevant host composition variable for explaining disease intensity by resource dilution. Indeed, cacao tree density probably affected disease intensity more by the creation of self-shading rather than by host dilution. Lastly, only regularly distributed forest trees, and not aggregated or randomly distributed forest trees, reduced disease intensity in comparison to plots with a low forest tree density. A regular spatial structure is probably crucial to the creation of moderate and uniform shade as recommended for frosty pod rot management. As pod production is an important service expected from these agroforests, shade tree spatial structure may be a lever for integrated management of frosty pod rot in cacao agroforests.

Traditional test administration and proactive interference undermine visual-spatial working memory performance in schizophrenia-spectrum disorders.

PubMed

Girard, Todd A; Wilkins, Leanne K; Lyons, Kathleen M; Yang, Lixia; Christensen, Bruce K

2018-05-31

Introduction Working-memory (WM) is a core cognitive deficit among individuals with Schizophrenia Spectrum Disorders (SSD). However, the underlying cognitive mechanisms of this deficit are less known. This study applies a modified version of the Corsi Block Test to investigate the role of proactive interference in visuospatial WM (VSWM) impairment in SSD. Methods Healthy and SSD participants completed a modified version of the Corsi Block Test involving both high (typical ascending set size from 4 to 7 items) and low (descending set size from 7 to 4 items) proactive interference conditions. Results The results confirmed that the SSD group performed worse overall relative to a healthy comparison group. More importantly, the SSD group demonstrated greater VSWM scores under low (Descending) versus high (Ascending) proactive interference; this pattern is opposite to that of healthy participants. Conclusions This differential pattern of performance supports that proactive interference associated with the traditional administration format contributes to VSWM impairment in SSD. Further research investigating associated neurocognitive mechanisms and the contribution of proactive interference across other domains of cognition in SSD is warranted.

Magnetic resonance spectroscopic imaging at superresolution: Overview and perspectives

NASA Astrophysics Data System (ADS)

Kasten, Jeffrey; Klauser, Antoine; Lazeyras, François; Van De Ville, Dimitri

2016-02-01

The notion of non-invasive, high-resolution spatial mapping of metabolite concentrations has long enticed the medical community. While magnetic resonance spectroscopic imaging (MRSI) is capable of achieving the requisite spatio-spectral localization, it has traditionally been encumbered by significant resolution constraints that have thus far undermined its clinical utility. To surpass these obstacles, research efforts have primarily focused on hardware enhancements or the development of accelerated acquisition strategies to improve the experimental sensitivity per unit time. Concomitantly, a number of innovative reconstruction techniques have emerged as alternatives to the standard inverse discrete Fourier transform (DFT). While perhaps lesser known, these latter methods strive to effect commensurate resolution gains by exploiting known properties of the underlying MRSI signal in concert with advanced image and signal processing techniques. This review article aims to aggregate and provide an overview of the past few decades of so-called "superresolution" MRSI reconstruction methodologies, and to introduce readers to current state-of-the-art approaches. A number of perspectives are then offered as to the future of high-resolution MRSI, with a particular focus on translation into clinical settings.

Hippocampal structure and human cognition: key role of spatial processing and evidence supporting the efficiency hypothesis in females

PubMed Central

Colom, Roberto; Stein, Jason L.; Rajagopalan, Priya; Martínez, Kenia; Hermel, David; Wang, Yalin; Álvarez-Linera, Juan; Burgaleta, Miguel; Quiroga, MªÁngeles; Shih, Pei Chun; Thompson, Paul M.

2014-01-01

Here we apply a method for automated segmentation of the hippocampus in 3D high-resolution structural brain MRI scans. One hundred and four healthy young adults completed twenty one tasks measuring abstract, verbal, and spatial intelligence, along with working memory, executive control, attention, and processing speed. After permutation tests corrected for multiple comparisons across vertices (p < .05) significant relationships were found for spatial intelligence, spatial working memory, and spatial executive control. Interactions with sex revealed significant relationships with the general factor of intelligence (g), along with abstract and spatial intelligence. These correlations were mainly positive for males but negative for females, which might support the efficiency hypothesis in women. Verbal intelligence, attention, and processing speed were not related to hippocampal structural differences. PMID:25632167

Pregnancy and birth in an indigenous Huichol community: from structural violence to structural policy responses.

PubMed

Gamlin, Jennie B; Hawkes, Sarah J

2015-01-01

Mexico's indigenous regions are characterised by socio-economic marginalisation and poor health outcomes and the Maternal Mortality Rate in indigenous communities continues to be around six times higher than the national rate. Using as a case study the Huichol community of North-Western Mexico we will discuss how institutional health and welfare programmes which aim to address accepted risk factors for maternal health are undermined by a series of structural barriers which put indigenous women especially in harm's way. Semi-structured interviews and observational data were gathered between 2009 and 2011 in highland communities and on coastal tobacco plantations to where a large number of this ethnic group migrate. Many Huichol women birth alone, and to facilitate this process they maintain a low nutritional intake to reduce their infant's growth and seek spiritual guidance during pregnancy from a shaman. These practices are reinforced by feelings of shame and humiliation encountered when using institutional health provision. These are some of the structural barriers to care that need to be addressed. Effective interventions could include addressing the training of health professionals, focusing on educational inequalities and the structural determinants of poverty whilst designing locally specific programmes that encourage acceptance of available health care.

Study on spatial structure of retailing based on GIS in the city of Wuhan

NASA Astrophysics Data System (ADS)

Liu, Cheng-liang; Tian, Ying

2008-10-01

With the agility of market economy, the characteristic of market spatial structure becomes more complex since the reformation and open policy. The spatial structure has broken through the traditional framework which is non-equilibriums and scattered, and represented such modern development character as diversification, grade, network, and non-equilibrium. This paper chooses 200 stochastic retailing stores whose acreages all exceed 40m2 in the four circles of Wuhan city, after the analysis of spatial difference on acreages, number, population density, and manage forms with GIS spatial methods, and makes a conclusion that the retailing spatial structure of Wuhan city has took on figure of rating circle wholly and frame of centralization-diffusion and enchasing partially; as location is concerned, centralization and diffusion takes place simultaneously, has behaved that retailing concentrated in heartland of city with more favorable traffic and market location by the means of market infiltration, and distributed in suburb more dispersive by market monopoly.

Fine-scale population dynamics in a marine fish species inferred from dynamic state-space models.

PubMed

Rogers, Lauren A; Storvik, Geir O; Knutsen, Halvor; Olsen, Esben M; Stenseth, Nils C

2017-07-01

Identifying the spatial scale of population structuring is critical for the conservation of natural populations and for drawing accurate ecological inferences. However, population studies often use spatially aggregated data to draw inferences about population trends and drivers, potentially masking ecologically relevant population sub-structure and dynamics. The goals of this study were to investigate how population dynamics models with and without spatial structure affect inferences on population trends and the identification of intrinsic drivers of population dynamics (e.g. density dependence). Specifically, we developed dynamic, age-structured, state-space models to test different hypotheses regarding the spatial structure of a population complex of coastal Atlantic cod (Gadus morhua). Data were from a 93-year survey of juvenile (age 0 and 1) cod sampled along >200 km of the Norwegian Skagerrak coast. We compared two models: one which assumes all sampled cod belong to one larger population, and a second which assumes that each fjord contains a unique population with locally determined dynamics. Using the best supported model, we then reconstructed the historical spatial and temporal dynamics of Skagerrak coastal cod. Cross-validation showed that the spatially structured model with local dynamics had better predictive ability. Furthermore, posterior predictive checks showed that a model which assumes one homogeneous population failed to capture the spatial correlation pattern present in the survey data. The spatially structured model indicated that population trends differed markedly among fjords, as did estimates of population parameters including density-dependent survival. Recent biomass was estimated to be at a near-record low all along the coast, but the finer scale model indicated that the decline occurred at different times in different regions. Warm temperatures were associated with poor recruitment, but local changes in habitat and fishing pressure may have played a role in driving local dynamics. More generally, we demonstrated how state-space models can be used to test evidence for population spatial structure based on survey time-series data. Our study shows the importance of considering spatially structured dynamics, as the inferences from such an approach can lead to a different ecological understanding of the drivers of population declines, and fundamentally different management actions to restore populations. © 2017 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.

On parts and holes: the spatial structure of the human body.

PubMed

Donnelly, Maureen

2004-01-01

Spatial representation and reasoning is a central component of medical informatics. The spatial concepts most often used in medicine are not the quantitative, point-based concepts of classical geometry, but rather qualitative relations among extended objects such as body parts. A mereotopology is a formal theory of qualitative spatial relations, such as parthood and connection. This paper considers how an extension of mereotopology which includes also location relations can be used to represent and reason about the spatial structure of the human body.

Spatial evolutionary epidemiology of spreading epidemics

PubMed Central

2016-01-01

Most spatial models of host–parasite interactions either neglect the possibility of pathogen evolution or consider that this process is slow enough for epidemiological dynamics to reach an equilibrium on a fast timescale. Here, we propose a novel approach to jointly model the epidemiological and evolutionary dynamics of spatially structured host and pathogen populations. Starting from a multi-strain epidemiological model, we use a combination of spatial moment equations and quantitative genetics to analyse the dynamics of mean transmission and virulence in the population. A key insight of our approach is that, even in the absence of long-term evolutionary consequences, spatial structure can affect the short-term evolution of pathogens because of the build-up of spatial differentiation in mean virulence. We show that spatial differentiation is driven by a balance between epidemiological and genetic effects, and this quantity is related to the effect of kin competition discussed in previous studies of parasite evolution in spatially structured host populations. Our analysis can be used to understand and predict the transient evolutionary dynamics of pathogens and the emergence of spatial patterns of phenotypic variation. PMID:27798295

Spatial evolutionary epidemiology of spreading epidemics.

PubMed

Lion, S; Gandon, S

2016-10-26

Most spatial models of host-parasite interactions either neglect the possibility of pathogen evolution or consider that this process is slow enough for epidemiological dynamics to reach an equilibrium on a fast timescale. Here, we propose a novel approach to jointly model the epidemiological and evolutionary dynamics of spatially structured host and pathogen populations. Starting from a multi-strain epidemiological model, we use a combination of spatial moment equations and quantitative genetics to analyse the dynamics of mean transmission and virulence in the population. A key insight of our approach is that, even in the absence of long-term evolutionary consequences, spatial structure can affect the short-term evolution of pathogens because of the build-up of spatial differentiation in mean virulence. We show that spatial differentiation is driven by a balance between epidemiological and genetic effects, and this quantity is related to the effect of kin competition discussed in previous studies of parasite evolution in spatially structured host populations. Our analysis can be used to understand and predict the transient evolutionary dynamics of pathogens and the emergence of spatial patterns of phenotypic variation. © 2016 The Author(s).

Using Quantum Confinement to Uniquely Identify Devices

PubMed Central

Roberts, J.; Bagci, I. E.; Zawawi, M. A. M.; Sexton, J.; Hulbert, N.; Noori, Y. J.; Young, M. P.; Woodhead, C. S.; Missous, M.; Migliorato, M. A.; Roedig, U.; Young, R. J.

2015-01-01

Modern technology unintentionally provides resources that enable the trust of everyday interactions to be undermined. Some authentication schemes address this issue using devices that give a unique output in response to a challenge. These signatures are generated by hard-to-predict physical responses derived from structural characteristics, which lend themselves to two different architectures, known as unique objects (UNOs) and physically unclonable functions (PUFs). The classical design of UNOs and PUFs limits their size and, in some cases, their security. Here we show that quantum confinement lends itself to the provision of unique identities at the nanoscale, by using fluctuations in tunnelling measurements through quantum wells in resonant tunnelling diodes (RTDs). This provides an uncomplicated measurement of identity without conventional resource limitations whilst providing robust security. The confined energy levels are highly sensitive to the specific nanostructure within each RTD, resulting in a distinct tunnelling spectrum for every device, as they contain a unique and unpredictable structure that is presently impossible to clone. This new class of authentication device operates with minimal resources in simple electronic structures above room temperature. PMID:26553435

Multilayer networks reveal the spatial structure of seed-dispersal interactions across the Great Rift landscapes.

PubMed

Timóteo, Sérgio; Correia, Marta; Rodríguez-Echeverría, Susana; Freitas, Helena; Heleno, Ruben

2018-01-10

Species interaction networks are traditionally explored as discrete entities with well-defined spatial borders, an oversimplification likely impairing their applicability. Using a multilayer network approach, explicitly accounting for inter-habitat connectivity, we investigate the spatial structure of seed-dispersal networks across the Gorongosa National Park, Mozambique. We show that the overall seed-dispersal network is composed by spatially explicit communities of dispersers spanning across habitats, functionally linking the landscape mosaic. Inter-habitat connectivity determines spatial structure, which cannot be accurately described with standard monolayer approaches either splitting or merging habitats. Multilayer modularity cannot be predicted by null models randomizing either interactions within each habitat or those linking habitats; however, as habitat connectivity increases, random processes become more important for overall structure. The importance of dispersers for the overall network structure is captured by multilayer versatility but not by standard metrics. Highly versatile species disperse many plant species across multiple habitats, being critical to landscape functional cohesion.

Identity and collective action among European Kurds.

PubMed

Ufkes, Elze G; Dovidio, John F; Tel, Gulizar

2015-03-01

This research investigated the role of group-based anger and efficacy in explaining the effects of subgroup (ethnic) and common (European) identity on collective action among Kurds in Europe responding to different types of disadvantage. Whereas stronger Kurdish identity positively predicted intentions for collective action (mediated by anger and efficacy), stronger common ingroup identity was negatively related to collective action intentions. This effect occurred primarily when structural disadvantage was salient, not when attention was drawn to a specific incident of disadvantage, and was mediated by anger but not efficacy. The findings complement recent work demonstrating that intergroup harmony can undermine social change, suggesting that stronger common-group identification reduces collective action by reducing minority-group members' sensitivity to potential bias against them. © 2014 The British Psychological Society.

Reply to comments by Riley and Dunlop on He et al. (2015)

USGS Publications Warehouse

Bence, James R.; Madenjian, Charles P.; He, Ji X.; Fielder, David G.; Pothoven, Steven A.; Dobiesz, Norine E.; Johnson, James E.; Ebener, Mark P.; Cottrill, R. Adam; Mohr, Lloyd C.; Koproski, Scott R.

2016-01-01

He et al. (2015) described piscivory patterns in the main basin of Lake Huron 1984-2010, during which there was also a pattern of stepwise declines in the abundance of dominant prey fish species. The approach of He et al. (2015) was to couple age-structured stock assessment and fish bioenergetics models to estimate prey fish consumption, and to compare these patterns with prey fish biomass from a bottom trawl survey. Riley and Dunlop (2015) were highly critical of the methods and conclusions reached by He et al. (2015). They claimed that we incorrectly interpreted the bottom trawl survey data, and did not account for uncertainty. We respond to these and other criticisms below, which we find do not undermine our findings.

Macroeconomic policy, growth, and biodiversity conservation.

PubMed

Lawn, Philip

2008-12-01

To successfully achieve biodiversity conservation, the amount of ecosystem structure available for economic production must be determined by, and subject to, conservation needs. As such, the scale of economic systems must remain within the limits imposed by the need to preserve critical ecosystems and the regenerative and waste assimilative capacities of the ecosphere. These limits are determined by biophysical criteria, yet macroeconomics involves the use of economic instruments designed to meet economic criteria that have no capacity to achieve biophysically based targets. Macroeconomic policy cannot, therefore, directly solve the biodiversity erosion crisis. Nevertheless, good macroeconomic policy is still important given that bad macroeconomy policy is likely to reduce human well-being and increase the likelihood of social upheaval that could undermine conservation efforts.

Multiple Scales of Control on the Structure and Spatial Distribution of Woody Vegetation in African Savanna Watersheds

PubMed Central

Vaughn, Nicholas R.; Asner, Gregory P.; Smit, Izak P. J.; Riddel, Edward S.

2015-01-01

Factors controlling savanna woody vegetation structure vary at multiple spatial and temporal scales, and as a consequence, unraveling their combined effects has proven to be a classic challenge in savanna ecology. We used airborne LiDAR (light detection and ranging) to map three-dimensional woody vegetation structure throughout four savanna watersheds, each contrasting in geologic substrate and climate, in Kruger National Park, South Africa. By comparison of the four watersheds, we found that geologic substrate had a stronger effect than climate in determining watershed-scale differences in vegetation structural properties, including cover, height and crown density. Generalized Linear Models were used to assess the spatial distribution of woody vegetation structural properties, including cover, height and crown density, in relation to mapped hydrologic, topographic and fire history traits. For each substrate and climate combination, models incorporating topography, hydrology and fire history explained up to 30% of the remaining variation in woody canopy structure, but inclusion of a spatial autocovariate term further improved model performance. Both crown density and the cover of shorter woody canopies were determined more by unknown factors likely to be changing on smaller spatial scales, such as soil texture, herbivore abundance or fire behavior, than by our mapped regional-scale changes in topography and hydrology. We also detected patterns in spatial covariance at distances up to 50–450 m, depending on watershed and structural metric. Our results suggest that large-scale environmental factors play a smaller role than is often attributed to them in determining woody vegetation structure in southern African savannas. This highlights the need for more spatially-explicit, wide-area analyses using high resolution remote sensing techniques. PMID:26660502

Multiple Scales of Control on the Structure and Spatial Distribution of Woody Vegetation in African Savanna Watersheds.

PubMed

Vaughn, Nicholas R; Asner, Gregory P; Smit, Izak P J; Riddel, Edward S

2015-01-01

Factors controlling savanna woody vegetation structure vary at multiple spatial and temporal scales, and as a consequence, unraveling their combined effects has proven to be a classic challenge in savanna ecology. We used airborne LiDAR (light detection and ranging) to map three-dimensional woody vegetation structure throughout four savanna watersheds, each contrasting in geologic substrate and climate, in Kruger National Park, South Africa. By comparison of the four watersheds, we found that geologic substrate had a stronger effect than climate in determining watershed-scale differences in vegetation structural properties, including cover, height and crown density. Generalized Linear Models were used to assess the spatial distribution of woody vegetation structural properties, including cover, height and crown density, in relation to mapped hydrologic, topographic and fire history traits. For each substrate and climate combination, models incorporating topography, hydrology and fire history explained up to 30% of the remaining variation in woody canopy structure, but inclusion of a spatial autocovariate term further improved model performance. Both crown density and the cover of shorter woody canopies were determined more by unknown factors likely to be changing on smaller spatial scales, such as soil texture, herbivore abundance or fire behavior, than by our mapped regional-scale changes in topography and hydrology. We also detected patterns in spatial covariance at distances up to 50-450 m, depending on watershed and structural metric. Our results suggest that large-scale environmental factors play a smaller role than is often attributed to them in determining woody vegetation structure in southern African savannas. This highlights the need for more spatially-explicit, wide-area analyses using high resolution remote sensing techniques.

Structural adjustment programmes adversely affect vulnerable populations: a systematic-narrative review of their effect on child and maternal health.

PubMed

Thomson, Michael; Kentikelenis, Alexander; Stubbs, Thomas

2017-01-01

Structural adjustment programmes of international financial institutions have typically set the fiscal parameters within which health policies operate in developing countries. Yet, we currently lack a systematic understanding of the ways in which these programmes impact upon child and maternal health. The present article systematically reviews observational and quasi-experimental articles published from 2000 onward in electronic databases (PubMed/Medline, Web of Science, Cochrane Library and Google Scholar) and grey literature from websites of key organisations (IMF, World Bank and African Development Bank). Studies were considered eligible if they empirically assessed the aggregate effect of structural adjustment programmes on child or maternal health in developing countries. Of 1961 items yielded through database searches, reference lists and organisations' websites, 13 met the inclusion criteria. Our review finds that structural adjustment programmes have a detrimental impact on child and maternal health. In particular, these programmes undermine access to quality and affordable healthcare and adversely impact upon social determinants of health, such as income and food availability. The evidence suggests that a fundamental rethinking is required by international financial institutions if developing countries are to achieve the Sustainable Development Goals on child and maternal health.

Phage-Bacterial Dynamics with Spatial Structure: Self Organization around Phage Sinks Can Promote Increased Cell Densities

PubMed Central

Bull, James J.; Christensen, Kelly A.; Scott, Carly; Crandall, Cameron J.; Krone, Stephen M.

2018-01-01

Bacteria growing on surfaces appear to be profoundly more resistant to control by lytic bacteriophages than do the same cells grown in liquid. Here, we use simulation models to investigate whether spatial structure per se can account for this increased cell density in the presence of phages. A measure is derived for comparing cell densities between growth in spatially structured environments versus well mixed environments (known as mass action). Maintenance of sensitive cells requires some form of phage death; we invoke death mechanisms that are spatially fixed, as if produced by cells. Spatially structured phage death provides cells with a means of protection that can boost cell densities an order of magnitude above that attained under mass action, although the effect is sometimes in the opposite direction. Phage and bacteria self organize into separate refuges, and spatial structure operates so that the phage progeny from a single burst do not have independent fates (as they do with mass action). Phage incur a high loss when invading protected areas that have high cell densities, resulting in greater protection for the cells. By the same metric, mass action dynamics either show no sustained bacterial elevation or oscillate between states of low and high cell densities and an elevated average. The elevated cell densities observed in models with spatial structure do not approach the empirically observed increased density of cells in structured environments with phages (which can be many orders of magnitude), so the empirical phenomenon likely requires additional mechanisms than those analyzed here. PMID:29382134

"Who's winning the human race?"Cold war as pharmaceutical political strategy.

PubMed

Tobbell, Dominique A

2009-10-01

Between 1959 and 1962, Senator Estes Kefauver led a congressional investigation into the pricing practices of U.S. drug firms. As part of its defense, the industry mobilized the rhetoric of cold war and promoted the industry as a critical national asset in the global war against communism. The industry argued that any effort to undermine corporate innovation by inviting, as Kefauver proposed, greater government involvement in drug development threatened the public's health and invited socialism-in the form of socialized medicine-into the domestic political economy. This strategy proved critical to the industry's efforts to build political support for itself, particularly among the medical profession, and undermine Kefauver's reform agenda.

Nursing's orphans: how the system of nursing education in Australia is undermining professional identity.

PubMed

Madsen, Wendy; McAllister, Margaret; Godden, Judith; Greenhill, Jennene; Reed, Rachel

2009-01-01

This paper draws on the results of a national study of approaches to teaching nursing's history in Australia. We argue that the neglect of history learning within undergraduate nursing and midwifery education is undermining the development in students of a strong professional nursing identity. The data in our study shows that instead of proud, informed professionals, we are at risk of producing a generation of professional orphans -- unaware of who they are and where they've come from, unaware of reasons underlying cultural practices within the profession, lacking in vision for the future, insecure about their capacity to contribute to future directions, and not feeling part of something bigger and more enduring.

Forbidden fruit: inattention to attractive alternatives provokes implicit relationship reactance.

PubMed

DeWall, C Nathan; Maner, Jon K; Deckman, Timothy; Rouby, D Aaron

2011-04-01

Being inattentive to attractive relationship alternatives can enhance relationship well-being. The current investigation, however, demonstrates that implicitly preventing people from attending to desirable relationship alternatives may undermine, rather than bolster, the strength of that person's romantic relationship. Consistent with the notion of "forbidden fruit," we found that subtly limiting people's attention to attractive alternatives reduced relationship satisfaction and commitment and increased positive attitudes toward infidelity (Experiment 1), increased memory for attractive relationship alternatives (Experiment 2), and increased attention to attractive alternatives (Experiment 3). Findings suggest that although attention to attractive alternatives can harm one's relationship, situations that implicitly limit one's attention to alternatives can, rather ironically, increase the temptation of alternatives and undermine relationship well-being.

Hale and Hearty Policies: How Psychological Science Can Create and Maintain Healthy Habits.

PubMed

Rothman, Alexander J; Gollwitzer, Peter M; Grant, Adam M; Neal, David T; Sheeran, Paschal; Wood, Wendy

2015-11-01

Strategies are needed to ensure that the U.S. Government meets its goals for improving the health of the nation (e.g., Healthy People 2020). To date, progress toward these goals has been undermined by a set of discernible challenges: People lack sufficient motivation, they frequently fail to translate healthy intentions into action, their efforts are undermined by the persistence of prior unhealthy habits, and they have considerable difficulty maintaining new healthy patterns of behavior. Guided by advances in psychological science, we provide innovative, evidence-based policies that address each of these challenges and, if implemented, will enhance people's ability to create and maintain healthy behavioral practices. © The Author(s) 2015.

Experimental philosophy and the problem of free will.

PubMed

Nichols, Shaun

2011-03-18

Many philosophical problems are rooted in everyday thought, and experimental philosophy uses social scientific techniques to study the psychological underpinnings of such problems. In the case of free will, research suggests that people in a diverse range of cultures reject determinism, but people give conflicting responses on whether determinism would undermine moral responsibility. When presented with abstract questions, people tend to maintain that determinism would undermine responsibility, but when presented with concrete cases of wrongdoing, people tend to say that determinism is consistent with moral responsibility. It remains unclear why people reject determinism and what drives people's conflicted attitudes about responsibility. Experimental philosophy aims to address these issues and thereby illuminate the philosophical problem of free will.

Legacy of Pre-Disturbance Spatial Pattern Determines Early Structural Diversity following Severe Disturbance in Montane Spruce Forests

PubMed Central

Bače, Radek; Svoboda, Miroslav; Janda, Pavel; Morrissey, Robert C.; Wild, Jan; Clear, Jennifer L.; Čada, Vojtěch; Donato, Daniel C.

2015-01-01

Background Severe canopy-removing disturbances are native to many temperate forests and radically alter stand structure, but biotic legacies (surviving elements or patterns) can lend continuity to ecosystem function after such events. Poorly understood is the degree to which the structural complexity of an old-growth forest carries over to the next stand. We asked how pre-disturbance spatial pattern acts as a legacy to influence post-disturbance stand structure, and how this legacy influences the structural diversity within the early-seral stand. Methods Two stem-mapped one-hectare forest plots in the Czech Republic experienced a severe bark beetle outbreak, thus providing before-and-after data on spatial patterns in live and dead trees, crown projections, down logs, and herb cover. Results Post-disturbance stands were dominated by an advanced regeneration layer present before the disturbance. Both major species, Norway spruce (Picea abies) and rowan (Sorbus aucuparia), were strongly self-aggregated and also clustered to former canopy trees, pre-disturbance snags, stumps and logs, suggesting positive overstory to understory neighbourhood effects. Thus, although the disturbance dramatically reduced the stand’s height profile with ~100% mortality of the canopy layer, the spatial structure of post-disturbance stands still closely reflected the pre-disturbance structure. The former upper tree layer influenced advanced regeneration through microsite and light limitation. Under formerly dense canopies, regeneration density was high but relatively homogeneous in height; while in former small gaps with greater herb cover, regeneration density was lower but with greater heterogeneity in heights. Conclusion These findings suggest that pre-disturbance spatial patterns of forests can persist through severe canopy-removing disturbance, and determine the spatial structure of the succeeding stand. Such patterns constitute a subtle but key legacy effect, promoting structural complexity in early-seral forests as well as variable successional pathways and rates. This influence suggests a continuity in spatial ecosystem structure that may well persist through multiple forest generations. PMID:26421726

Modeling structural change in spatial system dynamics: A Daisyworld example.

PubMed

Neuwirth, C; Peck, A; Simonović, S P

2015-03-01

System dynamics (SD) is an effective approach for helping reveal the temporal behavior of complex systems. Although there have been recent developments in expanding SD to include systems' spatial dependencies, most applications have been restricted to the simulation of diffusion processes; this is especially true for models on structural change (e.g. LULC modeling). To address this shortcoming, a Python program is proposed to tightly couple SD software to a Geographic Information System (GIS). The approach provides the required capacities for handling bidirectional and synchronized interactions of operations between SD and GIS. In order to illustrate the concept and the techniques proposed for simulating structural changes, a fictitious environment called Daisyworld has been recreated in a spatial system dynamics (SSD) environment. The comparison of spatial and non-spatial simulations emphasizes the importance of considering spatio-temporal feedbacks. Finally, practical applications of structural change models in agriculture and disaster management are proposed.

Spatially variant periodic structures in electromagnetics.

PubMed

Rumpf, Raymond C; Pazos, Javier J; Digaum, Jennefir L; Kuebler, Stephen M

2015-08-28

Spatial transforms are a popular technique for designing periodic structures that are macroscopically inhomogeneous. The structures are often required to be anisotropic, provide a magnetic response, and to have extreme values for the constitutive parameters in Maxwell's equations. Metamaterials and photonic crystals are capable of providing these, although sometimes only approximately. The problem still remains about how to generate the geometry of the final lattice when it is functionally graded, or spatially varied. This paper describes a simple numerical technique to spatially vary any periodic structure while minimizing deformations to the unit cells that would weaken or destroy the electromagnetic properties. New developments in this algorithm are disclosed that increase efficiency, improve the quality of the lattices and provide the ability to design aplanatic metasurfaces. The ability to spatially vary a lattice in this manner enables new design paradigms that are not possible using spatial transforms, three of which are discussed here. First, spatially variant self-collimating photonic crystals are shown to flow unguided waves around very tight bends using ordinary materials with low refractive index. Second, multi-mode waveguides in spatially variant band gap materials are shown to guide waves around bends without mixing power between the modes. Third, spatially variant anisotropic materials are shown to sculpt the near-field around electric components. This can be used to improve electromagnetic compatibility between components in close proximity. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Spatially variant periodic structures in electromagnetics

PubMed Central

Rumpf, Raymond C.; Pazos, Javier J.; Digaum, Jennefir L.; Kuebler, Stephen M.

2015-01-01

Spatial transforms are a popular technique for designing periodic structures that are macroscopically inhomogeneous. The structures are often required to be anisotropic, provide a magnetic response, and to have extreme values for the constitutive parameters in Maxwell's equations. Metamaterials and photonic crystals are capable of providing these, although sometimes only approximately. The problem still remains about how to generate the geometry of the final lattice when it is functionally graded, or spatially varied. This paper describes a simple numerical technique to spatially vary any periodic structure while minimizing deformations to the unit cells that would weaken or destroy the electromagnetic properties. New developments in this algorithm are disclosed that increase efficiency, improve the quality of the lattices and provide the ability to design aplanatic metasurfaces. The ability to spatially vary a lattice in this manner enables new design paradigms that are not possible using spatial transforms, three of which are discussed here. First, spatially variant self-collimating photonic crystals are shown to flow unguided waves around very tight bends using ordinary materials with low refractive index. Second, multi-mode waveguides in spatially variant band gap materials are shown to guide waves around bends without mixing power between the modes. Third, spatially variant anisotropic materials are shown to sculpt the near-field around electric components. This can be used to improve electromagnetic compatibility between components in close proximity. PMID:26217058

Research on Ultrasonic Flaw Detection of Steel Weld in Spatial Grid Structure

NASA Astrophysics Data System (ADS)

Du, Tao; Sun, Jiandong; Fu, Shengguang; Zhang, Changquan; Gao, Qing

2017-06-01

The welding quality of spatial grid member is an important link in quality control of steel structure. The paper analyzed the reasons that the welding seam of small-bore pipe with thin wall grid structure is difficult to be detected by ultrasonic wave from the theoretical and practical aspects. A series of feasible detection methods was also proposed by improving probe and operation approaches in this paper, and the detection methods were verified by project cases. Over the years, the spatial grid structure is widely used the engineering by virtue of its several outstanding characteristics such as reasonable structure type, standard member, excellent space integrity and quick installation. The wide application of spatial grid structure brings higher requirements on nondestructive test of grid structure. The implementation of new Code for Construction Quality Acceptance of Steel Structure Work GB50205-2001 strengthens the site inspection of steel structure, especially the site inspection of ultrasonic flaw detection in steel weld. The detection for spatial grid member structured by small-bore and thin-walled pipes is difficult due to the irregular influence of sound pressure in near-field region of sound field, sound beam diffusion generated by small bore pipe and reduction of sensitivity. Therefore, it is quite significant to select correct detecting conditions. The spatial grid structure of welding ball and bolt ball is statically determinate structure with high-order axial force which is connected by member bars and joints. It is welded by shrouding or conehead of member bars and of member bar and bolt-node sphere. It is obvious that to ensure the quality of these welding positions is critical to the quality of overall grid structure. However, the complexity of weld structure and limitation of ultrasonic detection method cause many difficulties in detection. No satisfactory results will be obtained by the conventional detection technology, so some special approaches must be used.

Habitat risk assessment for regional ocean planning in the U.S. Northeast and Mid-Atlantic.

PubMed

Wyatt, Katherine H; Griffin, Robert; Guerry, Anne D; Ruckelshaus, Mary; Fogarty, Michael; Arkema, Katie K

2017-01-01

Coastal habitats provide important benefits to people, including habitat for species targeted by fisheries and opportunities for tourism and recreation. Yet, such human activities also can imperil these habitats and undermine the ecosystem services they provide to people. Cumulative risk assessment provides an analytical framework for synthesizing the influence of multiple stressors across habitats and decision-support for balancing human uses and ecosystem health. To explore cumulative risk to habitats in the U.S. Northeast and Mid-Atlantic Ocean Planning regions, we apply the open-source InVEST Habitat Risk Assessment model to 13 habitats and 31 stressors in an exposure-consequence framework. In doing so, we advance the science priorities of EBM and both regional planning bodies by synthesizing the wealth of available data to improve our understanding of human uses and how they affect marine resources. We find that risk to ecosystems is greatest first, along the coast, where a large number of stressors occur in close proximity and secondly, along the continental shelf, where fewer, higher consequence activities occur. Habitats at greatest risk include soft and hard-bottom nearshore areas, tidal flats, soft-bottom shelf habitat, and rocky intertidal zones-with the degree of risk varying spatially. Across all habitats, our results indicate that rising sea surface temperatures, commercial fishing, and shipping consistently and disproportionally contribute to risk. Further, our findings suggest that management in the nearshore will require simultaneously addressing the temporal and spatial overlap as well as intensity of multiple human activities and that management in the offshore requires more targeted efforts to reduce exposure from specific threats. We offer a transparent, generalizable approach to evaluating cumulative risk to multiple habitats and illustrate the spatially heterogeneous nature of impacts along the eastern Atlantic coast and the importance of spatial scale in estimating such impacts. These results offer a valuable decision-support tool by helping to constrain the decision space, focus attention on habitats and locations at the greatest risk, and highlight effect management strategies.

Habitat risk assessment for regional ocean planning in the U.S. Northeast and Mid-Atlantic

PubMed Central

Guerry, Anne D.; Ruckelshaus, Mary; Fogarty, Michael; Arkema, Katie K.

2017-01-01

Coastal habitats provide important benefits to people, including habitat for species targeted by fisheries and opportunities for tourism and recreation. Yet, such human activities also can imperil these habitats and undermine the ecosystem services they provide to people. Cumulative risk assessment provides an analytical framework for synthesizing the influence of multiple stressors across habitats and decision-support for balancing human uses and ecosystem health. To explore cumulative risk to habitats in the U.S. Northeast and Mid-Atlantic Ocean Planning regions, we apply the open-source InVEST Habitat Risk Assessment model to 13 habitats and 31 stressors in an exposure-consequence framework. In doing so, we advance the science priorities of EBM and both regional planning bodies by synthesizing the wealth of available data to improve our understanding of human uses and how they affect marine resources. We find that risk to ecosystems is greatest first, along the coast, where a large number of stressors occur in close proximity and secondly, along the continental shelf, where fewer, higher consequence activities occur. Habitats at greatest risk include soft and hard-bottom nearshore areas, tidal flats, soft-bottom shelf habitat, and rocky intertidal zones—with the degree of risk varying spatially. Across all habitats, our results indicate that rising sea surface temperatures, commercial fishing, and shipping consistently and disproportionally contribute to risk. Further, our findings suggest that management in the nearshore will require simultaneously addressing the temporal and spatial overlap as well as intensity of multiple human activities and that management in the offshore requires more targeted efforts to reduce exposure from specific threats. We offer a transparent, generalizable approach to evaluating cumulative risk to multiple habitats and illustrate the spatially heterogeneous nature of impacts along the eastern Atlantic coast and the importance of spatial scale in estimating such impacts. These results offer a valuable decision-support tool by helping to constrain the decision space, focus attention on habitats and locations at the greatest risk, and highlight effect management strategies. PMID:29261672

An integrated photogrammetric and spatial database management system for producing fully structured data using aerial and remote sensing images.

PubMed

Ahmadi, Farshid Farnood; Ebadi, Hamid

2009-01-01

3D spatial data acquired from aerial and remote sensing images by photogrammetric techniques is one of the most accurate and economic data sources for GIS, map production, and spatial data updating. However, there are still many problems concerning storage, structuring and appropriate management of spatial data obtained using these techniques. According to the capabilities of spatial database management systems (SDBMSs); direct integration of photogrammetric and spatial database management systems can save time and cost of producing and updating digital maps. This integration is accomplished by replacing digital maps with a single spatial database. Applying spatial databases overcomes the problem of managing spatial and attributes data in a coupled approach. This management approach is one of the main problems in GISs for using map products of photogrammetric workstations. Also by the means of these integrated systems, providing structured spatial data, based on OGC (Open GIS Consortium) standards and topological relations between different feature classes, is possible at the time of feature digitizing process. In this paper, the integration of photogrammetric systems and SDBMSs is evaluated. Then, different levels of integration are described. Finally design, implementation and test of a software package called Integrated Photogrammetric and Oracle Spatial Systems (IPOSS) is presented.

Fine-scale structure in the far-infrared Milky-Way

NASA Technical Reports Server (NTRS)

Waller, William H.; Wall, William F.; Reach, William T.; Varosi, Frank; Ebert, Rick; Laughlin, Gaylin; Boulanger, Francois

1995-01-01

This final report summarizes the work performed and which falls into five broad categories: (1) generation of a new data product (mosaics of the far-infrared emission in the Milky Way); (2) acquisition of associated data products at other wavelengths; (3) spatial filtering of the far-infrared mosaics and resulting images of the FIR fine-scale structure; (4) evaluation of the spatially filtered data; (5) characterization of the FIR fine-scale structure in terms of its spatial statistics; and (6) identification of interstellar counterparts to the FIR fine-scale structure.

Financial Motivation Undermines Maintenance in an Intensive Diet and Activity Intervention

PubMed Central

Moller, Arlen C.; McFadden, H. Gene; Hedeker, Donald; Spring, Bonnie

2012-01-01

Financial incentives are widely used in health behavior interventions. However, self-determination theory posits that emphasizing financial incentives can have negative consequences if experienced as controlling. Feeling controlled into performing a behavior tends to reduce enjoyment and undermine maintenance after financial contingencies are removed (the undermining effect). We assessed participants' context-specific financial motivation to participate in the Make Better Choices trial—a trial testing four different strategies for improving four health risk behaviors: low fruit and vegetable intake, high saturated fat intake, low physical activity, and high sedentary screen time. The primary outcome was overall healthy lifestyle change; weight loss was a secondary outcome. Financial incentives were contingent upon meeting behavior goals for 3 weeks and became contingent upon merely providing data during the 4.5-month maintenance period. Financial motivation for participation was assessed at baseline using a 7-item scale (α = .97). Across conditions, a main effect of financial motivation predicted a steeper rate of weight regained during the maintenance period, t(165) = 2.15, P = .04. Furthermore, financial motivation and gender interacted significantly in predicting maintenance of healthy diet and activity changes, t(160) = 2.42, P = .016, such that financial motivation had a more deleterious influence among men. Implications for practice and future research on incentivized lifestyle and weight interventions are discussed. PMID:22548152

Subtle Scientific Fallacies Undermine the Validity of Neuroendocrinological Research: Do Not Draw Premature Conclusions on the Role of Female Sex Hormones.

PubMed

Hengartner, Michael P

2017-01-01

Major scientific flaws such as reporting and publication biases are well documented, even though acknowledgment of their importance appears to be lacking in various psychological and medical fields. Subtle and less obvious biases including selective reviews of the literature and empirically unsupported conclusions and recommendations have received even less attention. Using the literature on the association between transition to menopause, hormones and the onset of depression as a guiding example, I outline how such scientific fallacies undermine the validity of neuroendocrinological research. It is shown that in contrast to prominent claims, first, most prospective studies do not support the notion that the menopausal transition relates to increased risk for depression, second, that associations between hormone levels and depression are largely inconsistent and irreproducible, and, third, that the evidence for the efficacy of hormone therapy for the treatment of depression is very weak and at best inconclusive. I conclude that a direct and uniform association between female sex hormones and depression is clearly not supported by the literature and that more attention should be paid to the manifold scientific biases that undermine the validity of findings in psychological and medical research, with a specific focus on the behavioral neurosciences.

Stereotype threat engenders neural attentional bias toward negative feedback to undermine performance.

PubMed

Forbes, Chad E; Leitner, Jordan B

2014-10-01

Stereotype threat, a situational pressure individuals experience when they fear confirming a negative group stereotype, engenders a cascade of physiological stress responses, negative appraisals, and performance monitoring processes that tax working memory resources necessary for optimal performance. Less is known, however, about how stereotype threat biases attentional processing in response to performance feedback, and how such attentional biases may undermine performance. Women received feedback on math problems in stereotype threatening compared to stereotype-neutral contexts while continuous EEG activity was recorded. Findings revealed that stereotype threatened women elicited larger midline P100 ERPs, increased phase locking between anterior cingulate cortex and dorsolateral prefrontal cortex (two regions integral for attentional processes), and increased power in left fusiform gyrus in response to negative feedback compared to positive feedback and women in stereotype-neutral contexts. Increased power in left fusiform gyrus in response to negative feedback predicted underperformance on the math task among stereotype threatened women only. Women in stereotype-neutral contexts exhibited the opposite trend. Findings suggest that in stereotype threatening contexts, neural networks integral for attention and working memory are biased toward negative, stereotype confirming feedback at very early speeds of information processing. This bias, in turn, plays a role in undermining performance. Copyright © 2014 Elsevier B.V. All rights reserved.

Consumer trust in the Australian food system - The everyday erosive impact of food labelling.

PubMed

Tonkin, Emma; Webb, Trevor; Coveney, John; Meyer, Samantha B; Wilson, Annabelle M

2016-08-01

Consumer trust in food system actors is foundational for ensuring consumer confidence in food safety. As food labelling is a direct communication between consumers and food system actors, it may influence consumer perceptions of actor trustworthiness. This study explores the judgements formed about the trustworthiness of the food system and its actors through labelling, and the expectations these judgements are based on. In-depth, semi-structured interviews with 24 Australian consumers were conducted. Theoretical sampling focussed on shopping location, dietary requirements, rurality, gender, age and educational background. The methodological approach used (adaptive theory) enabled emerging data to be examined through the lens of a set of guiding theoretical concepts, and theory reconsidered in light of emerging data. Food labelling acted as a surrogate for personal interaction with industry and government for participants. Judgements about the trustworthiness of these actors and the broader food system were formed through interaction with food labelling and were based on expectations of both competence and goodwill. Interaction with labelling primarily reduced trust in actors within the food system, undermining trust in the system as a whole. Labelling has a role as an access point to the food system. Access points are points of vulnerability for systems, where trust can be developed, reinforced or broken down. For the participants in this study, in general labelling demonstrates food system actors lack goodwill and violate their fiduciary responsibility. This paper provides crucial insights for industry and policy actors to use this access point to build, rather than undermine, trust in food systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Individuals with high obsessive-compulsive tendencies or undermined confidence rely more on external proxies to access their internal states.

PubMed

Zhang, Zhongming; Wang, Mengyun; Miao, Xiaocui; Li, Yijuan; Hitchman, Glenn; Yuan, Zhen

2017-03-01

The Seeking Proxies for Internal States (SPIS) hypothesis predicts that obsessive-compulsive disorder (OCD) is associated with a deficit in subjective convictions, which may lead to a reliance on external substitutes for the perceptions of an individual's internal states. Two well-designed studies were performed for the present work that adopted a false bio-feedback procedure in a muscle tension task to examine the SPIS hypothesis. The false bio-feedback paradigm was used to investigate our hypothesis. NeXus-10 Mark II hardware and V2011 BioTrace + software (Mind Media B.V., Herten, Netherlands) were utilized to measure the muscle tension of the flexor carpiulnaris muscle, which characterized the target's internal state. In addition, false EMG changes were recorded and displayed on a computer monitor and were considered external proxies. Study 1 demonstrated that the participants with high obsessive-compulsive (OC) tendencies were more affected by the false bio-feedback and exhibited lower confidence in their judgments regarding their muscle tension compared with the participants with low OC tendencies. These findings indicate that subjects with high OC tendencies were more influenced by self-perception effects. In contrast, the subjects in the undermined confidence group in Study 2 were more easily influenced by the false bio-feedback compared with the control group, which suggests that the subjects in the undermined confidence group were more affected by self-perception effects. We did not combine the undermined confidence with OC tendencies or OCD symptoms in our paradigm to investigate their joint effects on self-perception. Our findings provide further evidence that supports the SPIS hypothesis, which indicates that OC tendencies and the confidence in an individual's recognition of internal states appear to have similar effects on the assessment of internal states and reliance on proxies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Structural and Community Change Outcomes of the Connect-to-Protect Coalitions: Trials and Triumphs Securing Adolescent Access to HIV Prevention, Testing, and Medical Care.

PubMed

Miller, Robin Lin; Reed, Sarah J; Chiaramonte, Danielle; Strzyzykowski, Trevor; Spring, Hannah; Acevedo-Polakovich, Ignacio D; Chutuape, Kate; Cooper-Walker, Bendu; Boyer, Cherrie B; Ellen, Jonathan M

2017-09-01

Connect to Protect (C2P), a 10-year community mobilization effort, pursued the dual aims of creating communities competent to address youth's HIV-related risks and removing structural barriers to youth health. We used Community Coalition Action Theory (CCAT) to examine the perceived contributions and accomplishments of 14 C2P coalitions. We interviewed 318 key informants, including youth and community leaders, to identify the features of coalitions' context and operation that facilitated and undermined their ability to achieve structural change and build communities' capability to manage their local adolescent HIV epidemic effectively. We coded the interviews using an a priori coding scheme informed by CCAT and scholarship on AIDS-competent communities. We found community mobilization efforts like C2P can contribute to addressing the structural factors that promote HIV-risk among youth and to community development. We describe how coalition leadership, collaborative synergy, capacity building, and local community context influence coalitions' ability to successfully implement HIV-related structural change, demonstrating empirical support for many of CCAT's propositions. We discuss implications for how community mobilization efforts might succeed in laying the foundation for an AIDS-competent community. © Society for Community Research and Action 2017.

Spatial Patterns in Herbivory on a Coral Reef Are Influenced by Structural Complexity but Not by Algal Traits

PubMed Central

Vergés, Adriana; Vanderklift, Mathew A.; Doropoulos, Christopher; Hyndes, Glenn A.

2011-01-01

Background Patterns of herbivory can alter the spatial structure of ecosystems, with important consequences for ecosystem functions and biodiversity. While the factors that drive spatial patterns in herbivory in terrestrial systems are well established, comparatively less is known about what influences the distribution of herbivory in coral reefs. Methodology and Principal Findings We quantified spatial patterns of macroalgal consumption in a cross-section of Ningaloo Reef (Western Australia). We used a combination of descriptive and experimental approaches to assess the influence of multiple macroalgal traits and structural complexity in establishing the observed spatial patterns in macroalgal herbivory, and to identify potential feedback mechanisms between herbivory and macroalgal nutritional quality. Spatial patterns in macroalgal consumption were best explained by differences in structural complexity among habitats. The biomass of herbivorous fish, and rates of herbivory were always greater in the structurally-complex coral-dominated outer reef and reef flat habitats, which were also characterised by high biomass of herbivorous fish, low cover and biomass of macroalgae and the presence of unpalatable algae species. Macroalgal consumption decreased to undetectable levels within 75 m of structurally-complex reef habitat, and algae were most abundant in the structurally-simple lagoon habitats, which were also characterised by the presence of the most palatable algae species. In contrast to terrestrial ecosystems, herbivory patterns were not influenced by the distribution, productivity or nutritional quality of resources (macroalgae), and we found no evidence of a positive feedback between macroalgal consumption and the nitrogen content of algae. Significance This study highlights the importance of seascape-scale patterns in structural complexity in determining spatial patterns of macroalgal consumption by fish. Given the importance of herbivory in maintaining the ability of coral reefs to reorganise and retain ecosystem functions following disturbance, structural complexity emerges as a critical feature that is essential for the healthy functioning of these ecosystems. PMID:21347254

Significant demographic and fine-scale genetic structure in expanding and senescing populations of the terrestrial orchid Cymbidium goeringii (Orchidaceae).

PubMed

Chung, Mi Yoon; Nason, John D; Chung, Myong Gi

2011-12-01

Fine-scale genetic structure (FSGS) in plants is influenced by variation in spatial and temporal demographic processes. To determine how demographic structure and FSGS change with stages of population succession, we studied replicate expanding and senescing populations of the Asian terrestrial orchid Cymbidium goeringii. We used spatial autocorrelation methods (O-ring and kinship statistics) to quantify spatial demographic structure and FSGS in two expanding and two senescing populations, also measuring genetic diversity and inbreeding in each. All populations exhibited significant aggregation of individuals and FSGS at short spatial scales. In expanding populations, this finding was associated with high recruitment rates, suggesting restricted seed dispersal. In senescing populations, recruitment was minimal, suggesting alternative mechanisms of aggregation, perhaps including spatial associations with mycorrhizal fungi. All populations had significant evidence of genetic bottlenecks, and inbreeding levels were consistently high. Our results indicate that different successional stages can generate similar patterns of spatial demographic and genetic structure, but as a consequence of different processes. These results contrast with the only other study of senescence effects on population genetic structure in an herbaceous perennial, which found little to no FSGS in senescing populations. With the exception of populations subject to mass collection by orchid sellers, significant FSGS is characteristic of the 16 terrestrial orchid species examined to date. From a conservation perspective, this result suggests that inference of orchid population history will benefit from analyses of both FSGS and demographic structure in combination with other ecological field data.

Students' Spatial Structuring of 2D Arrays of Squares.

ERIC Educational Resources Information Center

Battista, Michael T.; Clements, Douglas H.; Arnoff, Judy; Battista, Kathryn; Van Auken Borrow, Caroline

1998-01-01

Defines spatial structuring as the mental operation of constructing an organization or form for an object/set of objects. Examines in detail students' structuring and enumeration of two-dimensional rectangular arrays of squares. Concludes that many students do not see row-by-column structure. Describes various levels of sophistication in students'…

Spatial network surrogates for disentangling complex system structure from spatial embedding of nodes

NASA Astrophysics Data System (ADS)

Wiedermann, Marc; Donges, Jonathan F.; Kurths, Jürgen; Donner, Reik V.

2016-04-01

Networks with nodes embedded in a metric space have gained increasing interest in recent years. The effects of spatial embedding on the networks' structural characteristics, however, are rarely taken into account when studying their macroscopic properties. Here, we propose a hierarchy of null models to generate random surrogates from a given spatially embedded network that can preserve certain global and local statistics associated with the nodes' embedding in a metric space. Comparing the original network's and the resulting surrogates' global characteristics allows one to quantify to what extent these characteristics are already predetermined by the spatial embedding of the nodes and links. We apply our framework to various real-world spatial networks and show that the proposed models capture macroscopic properties of the networks under study much better than standard random network models that do not account for the nodes' spatial embedding. Depending on the actual performance of the proposed null models, the networks are categorized into different classes. Since many real-world complex networks are in fact spatial networks, the proposed approach is relevant for disentangling the underlying complex system structure from spatial embedding of nodes in many fields, ranging from social systems over infrastructure and neurophysiology to climatology.

How has Radical Right Support Transformed Established Political Conflicts? The Case of Austria

PubMed Central

Aichholzer, Julian; Kritzinger, Sylvia; Wagner, Markus; Zeglovits, Eva

2014-01-01

In many European party systems, the radical right has challenged established patterns of political competition. This article studies the consequences of this by using the case of the Freedom Party of Austria (FPÖ) and data from Austria’s first national election study (AUTNES). It is found that the FPÖ has weakened Austria’s previously highly stable system of socio-structural and ideological divisions as expressed by the two mainstream parties, the People’s Party and the Social Democrats. In socio-structural terms, the FPÖ has undermined the Social Democrats’ support base. In ideological terms, FPÖ voters have distinct views on newer issues such as immigration, European integration and dissatisfaction with the political system, but its supporters’ views on Austria’s traditional conflicts surrounding the economy and social and religious values cannot explain the party’s success. These findings further our understanding of the transformation of political conflicts not just in Austria, but in Western Europe in general. PMID:26770003

Urban Congolese Refugees in Kenya: The Contingencies of Coping and Resilience in a Context Marked by Structural Vulnerability.

PubMed

Tippens, Julie A

2017-06-01

The global increase in refugee migration to urban areas creates challenges pertaining to the promotion of refugee health, broadly conceived. Despite considerable attention to trauma and forced migration, there is relatively little focus on how refugees cope with stressful situations, and on the determinants that facilitate and undermine resilience. This article examines how urban Congolese refugees in Kenya promote psychosocial well-being in the context of structural vulnerability. This article is based on interviews ( N = 55) and ethnographic participant observation with Congolese refugees over a period of 8 months in Nairobi in 2014. Primary stressors related to scarcity of material resources, political and personal insecurity, and emotional stress. Congolese refugees mitigated stressors by (a) relying on faith in God's plan and trust in religious community, (b) establishing borrowing networks, and (c) compartmentalizing the past and present. This research has broader implications for the promotion of urban refugees' psychosocial health and resilience in countries of first asylum.

The Best Possible Intentions Testing Prophylactic Approaches on Humans in Developing Countries

PubMed Central

2013-01-01

Debates on human experiments in developing countries focus on ethical principles such as informed consent, accountability, involvement of the concerned communities, and the improvement of local health services. Public health specialists who conducted human experiments in Rio de Janeiro (1902–1905) and in Guatemala (1947–1948) believed, however, that they were acting in the best interests of local populations, were aware of the importance of informed consent, were closely collaborating with local health professionals, and were contributing to the development of local health structures. Nevertheless, their investigations went dramatically wrong. An initial desire to conduct ethically and scientifically sound studies was undermined by pressure to obtain results and to save the researchers’ initial investment, the possibility of freely using hospitalized patients as experimental participants, uncritical help from local professional elites, and structural pitfalls of experimenting with severely deprived people. These elements can still be found in trials of preventive methods in the Global South. PMID:23237168

HIV treatment as prevention in Jamaica and Barbados: magic bullet or sustainable response?

PubMed

Barrow, Geoffrey; Barrow, Christine

2015-01-01

This discursive article introduces HIV treatment as prevention (TasP) and identifies various models for its extrapolation to wider population levels. Drawing on HIV surveillance data for Jamaica and Barbados, the article identifies significant gaps in HIV response programming in relation to testing, antiretroviral treatment coverage, and treatment adherence, thereby highlighting the disparity between assumptions and prerequisites for TasP success. These gaps are attributable, in large part, to sociocultural impediments and structural barriers, severe resource constraints, declining political will, and the redefinition of HIV as a manageable, chronic health issue. Antiretroviral treatment and TasP can realize success only within a combination prevention frame that addresses structural factors, including stigma and discrimination, gender inequality and gender-based violence, social inequality, and poverty. The remedicalization of the response compromises outcomes and undermines the continued potential of HIV programming as an entry point for the promotion of sexual, health, and human rights. © The Author(s) 2013.

Gender and globalization. A century in retrospect.

PubMed

Chinkin, C

2000-01-01

In the past, power structures of the nation-State have been organized around patriarchal assumptions, granting men monopoly over power, authority, and wealth. A number of structures have been erected to achieve this imbalance, which have disguised its inequity by making it appear as natural and universal. However, with globalization, this centralization of power within the Sovereign State has been fragmented. Although globalization opens up new spaces by weakening the nation-State, subsequently making possible the undermining of traditional gender hierarchies and devising new bases for gender relations, the reality that the State is no longer the sole institution that can define identity and belonging within it has denied women the space to assert their own claims to gendered self-determination. In this regard, globalization has impacted upon gender relations in complex and contradictory ways. This paper discusses such impacts of globalization on gender relations. Overall, it has become apparent that forms of inequality still exist regardless of a State's prevailing political ideology. Their manifestations may differ, but the reality of women's subordination remains constant.

Economic networks: Heterogeneity-induced vulnerability and loss of synchronization

NASA Astrophysics Data System (ADS)

Colon, Célian; Ghil, Michael

2017-12-01

Interconnected systems are prone to propagation of disturbances, which can undermine their resilience to external perturbations. Propagation dynamics can clearly be affected by potential time delays in the underlying processes. We investigate how such delays influence the resilience of production networks facing disruption of supply. Interdependencies between economic agents are modeled using systems of Boolean delay equations (BDEs); doing so allows us to introduce heterogeneity in production delays and in inventories. Complex network topologies are considered that reproduce realistic economic features, including a network of networks. Perturbations that would otherwise vanish can, because of delay heterogeneity, amplify and lead to permanent disruptions. This phenomenon is enabled by the interactions between short cyclic structures. Difference in delays between two interacting, and otherwise resilient, structures can in turn lead to loss of synchronization in damage propagation and thus prevent recovery. Finally, this study also shows that BDEs on complex networks can lead to metastable relaxation oscillations, which are damped out in one part of a network while moving on to another part.

Hunting or habitat? Drivers of waterbird abundance and community structure in agricultural wetlands of southern India.

PubMed

Ramachandran, Ramesh; Kumar, Ajith; Gopi Sundar, Kolla S; Bhalla, Ravinder Singh

2017-09-01

The relative impacts of hunting and habitat on waterbird community were studied in agricultural wetlands of southern India. We surveyed wetlands to document waterbird community, and interviewed hunters to document hunting intensity, targeted species, and the motivations for hunting. Our results show that hunting leads to drastic declines in waterbird diversity and numbers, and skew the community towards smaller species. Hunting intensity, water spread, and vegetation cover were the three most important determinants of waterbird abundance and community structure. Species richness, density of piscivorous species, and medium-sized species (31-65 cm) were most affected by hunting. Out of 53 species recorded, 47 were hunted, with a preference for larger birds. Although illegal, hunting has increased in recent years and is driven by market demand. This challenges the widely held belief that waterbird hunting in India is a low intensity, subsistence activity, and undermines the importance of agricultural wetlands in waterbird conservation.

In vitro assessment of ultraviolet protection of coloured cotton knitted fabrics with different structures under stretched and wet conditions.

PubMed

Wong, W Y; Lam, J K C; Kan, C W; Postle, R

2015-04-01

Clothing provides intrinsic ultraviolet (UV) protection that can be improved by colouration. However, the daily wearing condition can undermine the UV protection of coloured clothing wherein garments are stretched by body movement and/or wetted by perspiration of wearers. Knitwear is an indispensable clothing in summer, but its UV protection against wearing conditions lacks extensive study especially in a fabric structural approach. This article aimed at narrowing the research gap by focusing on the UV protection against stretch and wetness provided by various knitted fabric constructions incorporating the knit, tuck and miss stitches. The results show that the black knitted fabrics exhibit a significant reduction in the UV protection factor by 53% on average at a 10% stretch level. Knitted fabrics with miss stitches retained good UV protection even when the fabrics were stretched by 20% of its original dimensions. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The effect of migration on family structures in sub-Saharan Africa.

PubMed

Okoth-ogendo, H W

1989-06-01

This paper assesses the effect of migration or family structures in sub-Saharan Africa, especially the effect of emigration on the reproduction, production, and social stability of the family in areas of origin in the predominantly agrarian communities of East and Southern Africa. Migration in precolonial Africa usually occurred for 1 of the following reasons: 1) the search by communities for new habitats and opportunities; 2) as a community response to droughts, floods, environmental degradation, and similar disasters; and 3) as a result of internecine wars, civil strife, and general hostilities. Thus, because of the collective nature of early migrations, the family unit maintained a much greater degree of social cohesion. The effects of the rise of the modern state in Africa on migration include 1) spatial limits of collective migration were frozen, 2) the colonial boundaries did not always correspond to cultural divisions, 3) both migration within colonial boundaries and individual migration became dominant, and 4) cyclical migration began. The end of colonialism resulted in 1) difficulties in creating strong and internally coherent nation states because of the uncertainty of national borders and 2) more cyclical migrants. The effects of migration on reproduction in the family during the colonial period include 17 extremely low fertility rates, 2) widespread domestic instability, and 3) exacerbation of moral decadence. Contemporary patterns of emigration have been far less disruptive, due in part to increased personal mobility and migration of the complete reproductive unit. The effects of migration on production include 1) depletion of labor for production; 2) women had to assume production functions, together with all their other responsibilities; and 3) very little cash or goods were available for remittance to areas of origin. Production and productivity among rural African families will continue to suffer as long as plantations, mines, and urban centers entice the younger, more productive labor way. Migration can affect the social structure 1) by undermining basic social institutions including the family; or 2) by strengthening social solidarity especially if it occurs in the land frontier of the migrant's original society. Africa's migration policy should 1) allow for greater mobility within and across boundaries and 2) initiate policies and programs to achieve a more balanced settlement pattern, especially in rural Africa.

Bird-landscape relations in the Chihuahuan Desert: Coping with uncertainties about predictive models

USGS Publications Warehouse

Gutzwiller, K.J.; Barrow, W.C.

2001-01-01

During the springs of 1995-1997, we studied birds and landscapes in the Chihuahuan Desert along part of the Texas-Mexico border. Our objectives were to assess bird-landscape relations and their interannual consistency and to identify ways to cope with associated uncertainties that undermine confidence in using such relations in conservation decision processes. Bird distributions were often significantly associated with landscape features, and many bird-landscape models were valid and useful for predictive purposes. Differences in early spring rainfall appeared to influence bird abundance, but there was no evidence that annual differences in bird abundance affected model consistency. Model consistency for richness (42%) was higher than mean model consistency for 26 focal species (mean 30%, range 0-67%), suggesting that relations involving individual species are, on average, more subject to factors that cause variation than are richness-landscape relations. Consistency of bird-landscape relations may be influenced by such factors as plant succession, exotic species invasion, bird species' tolerances for environmental variation, habitat occupancy patterns, and variation in food density or weather. The low model consistency that we observed for most species indicates the high variation in bird-landscape relations that managers and other decision makers may encounter. The uncertainty of interannual variation in bird-landscape relations can be reduced by using projections of bird distributions from different annual models to determine the likely range of temporal and spatial variation in a species' distribution. Stochastic simulation models can be used to incorporate the uncertainty of random environmental variation into predictions of bird distributions based on bird-landscape relations and to provide probabilistic projections with which managers can weigh the costs and benefits of various decisions, Uncertainty about the true structure of bird-landscape relations (structural uncertainty) can be reduced by ensuring that models meet important statistical assumptions, designing studies with sufficient statistical power, validating the predictive ability of models, and improving model accuracy through continued field sampling and model fitting. Un certainty associated with sampling variation (partial observability) can be reduced by ensuring that sample sizes are large enough to provide precise estimates of both bird and landscape parameters. By decreasing the uncertainty due to partial observability, managers will improve their ability to reduce structural uncertainty.

Dispersal Ability Determines the Role of Environmental, Spatial and Temporal Drivers of Metacommunity Structure

PubMed Central

Padial, André A.; Ceschin, Fernanda; Declerck, Steven A. J.; De Meester, Luc; Bonecker, Cláudia C.; Lansac-Tôha, Fabio A.; Rodrigues, Liliana; Rodrigues, Luzia C.; Train, Sueli; Velho, Luiz F. M.; Bini, Luis M.

2014-01-01

Recently, community ecologists are focusing on the relative importance of local environmental factors and proxies to dispersal limitation to explain spatial variation in community structure. Albeit less explored, temporal processes may also be important in explaining species composition variation in metacommunities occupying dynamic systems. We aimed to evaluate the relative role of environmental, spatial and temporal variables on the metacommunity structure of different organism groups in the Upper Paraná River floodplain (Brazil). We used data on macrophytes, fish, benthic macroinvertebrates, zooplankton, periphyton, and phytoplankton collected in up to 36 habitats during a total of eight sampling campaigns over two years. According to variation partitioning results, the importance of predictors varied among biological groups. Spatial predictors were particularly important for organisms with comparatively lower dispersal ability, such as aquatic macrophytes and fish. On the other hand, environmental predictors were particularly important for organisms with high dispersal ability, such as microalgae, indicating the importance of species sorting processes in shaping the community structure of these organisms. The importance of watercourse distances increased when spatial variables were the main predictors of metacommunity structure. The contribution of temporal predictors was low. Our results emphasize the strength of a trait-based analysis and of better defining spatial variables. More importantly, they supported the view that “all-or- nothing” interpretations on the mechanisms structuring metacommunities are rather the exception than the rule. PMID:25340577

High-rise buildings in the structure of an urbanized landscape and their influence on the spatial composition and image of the city

NASA Astrophysics Data System (ADS)

Moor, Valery K.; Erysheva, Elena A.

2018-03-01

High-rise buildings play an important role in the spatial structure, composition and image of the city, as they are its spatial dominants and landmarks. The conditions of high-rise buildings perception in an urbanized landscape are changing in depending on the landscape-morphological conditions (the relief, the existence of the water area and the character of the coastline). Regularities of high-rise buildings' spatial organization in various natural-landscape situations are considered in the research; the basic principles of high-rise elements inclusion in structure of the urbanized landscape providing their harmonious interaction are formulated.

Sex-biased dispersal creates spatial genetic structure in a parthenogenetic ant with a dependent-lineage reproductive system.

PubMed

Kuhn, A; Bauman, D; Darras, H; Aron, S

2017-10-01

Reproduction and dispersal are key aspects of species life history that influence spatial genetic structure in populations. Several ant species in the genus Cataglyphis have evolved a unique breeding system in which new reproductives (that is, queens and males) are produced asexually by parthenogenesis; in contrast, non-reproductives (that is, workers) are produced via sexual reproduction by mates from distinct genetic lineages. We investigated how these two coexisting reproductive methods affect population-level spatial genetic structure using the ant Cataglyphis mauritanica as a model. We obtained genotypes for queens and their male mates from 338 colonies, and we found that the two lineages present in the study population occurred with equal frequency. Furthermore, analysis of spatial genetic structure revealed strong sex-biased dispersal. Because queens were produced by parthenogenesis and because they dispersed over short distances, there was an extreme level of spatial structuring: a mosaic of patches composed of clonal queens was formed. Males, on the other hand, dispersed over several hundred metres and, thus, across patches, ensuring successful interlineage mating.

Change of spatial information under rescaling: A case study using multi-resolution image series

NASA Astrophysics Data System (ADS)

Chen, Weirong; Henebry, Geoffrey M.

Spatial structure in imagery depends on a complicated interaction between the observational regime and the types and arrangements of entities within the scene that the image portrays. Although block averaging of pixels has commonly been used to simulate coarser resolution imagery, relatively little attention has been focused on the effects of simple rescaling on spatial structure and the explanation and a possible solution to the problem. Yet, if there are significant differences in spatial variance between rescaled and observed images, it may affect the reliability of retrieved biogeophysical quantities. To investigate these issues, a nested series of high spatial resolution digital imagery was collected at a research site in eastern Nebraska in 2001. An airborne Kodak DCS420IR camera acquired imagery at three altitudes, yielding nominal spatial resolutions ranging from 0.187 m to 1 m. The red and near infrared (NIR) bands of the co-registered image series were normalized using pseudo-invariant features, and the normalized difference vegetation index (NDVI) was calculated. Plots of grain sorghum planted in orthogonal crop row orientations were extracted from the image series. The finest spatial resolution data were then rescaled by averaging blocks of pixels to produce a rescaled image series that closely matched the spatial resolution of the observed image series. Spatial structures of the observed and rescaled image series were characterized using semivariogram analysis. Results for NDVI and its component bands show, as expected, that decreasing spatial resolution leads to decreasing spatial variability and increasing spatial dependence. However, compared to the observed data, the rescaled images contain more persistent spatial structure that exhibits limited variation in both spatial dependence and spatial heterogeneity. Rescaling via simple block averaging fails to consider the effect of scene object shape and extent on spatial information. As the features portrayed by pixels are equally weighted regardless of the shape and extent of the underlying scene objects, the rescaled image retains more of the original spatial information than would occur through direct observation at a coarser sensor spatial resolution. In contrast, for the observed images, due to the effect of the modulation transfer function (MTF) of the imaging system, high frequency features like edges are blurred or lost as the pixel size increases, resulting in greater variation in spatial structure. Successive applications of a low-pass spatial convolution filter are shown to mimic a MTF. Accordingly, it is recommended that such a procedure be applied prior to rescaling by simple block averaging, if insufficient image metadata exist to replicate the net MTF of the imaging system, as might be expected in land cover change analysis studies using historical imagery.

Metacommunity composition of web-spiders in a fragmented neotropical forest: relative importance of environmental and spatial effects.

PubMed

Baldissera, Ronei; Rodrigues, Everton N L; Hartz, Sandra M

2012-01-01

The distribution of beta diversity is shaped by factors linked to environmental and spatial control. The relative importance of both processes in structuring spider metacommunities has not yet been investigated in the Atlantic Forest. The variance explained by purely environmental, spatially structured environmental, and purely spatial components was compared for a metacommunity of web spiders. The study was carried out in 16 patches of Atlantic Forest in southern Brazil. Field work was done in one landscape mosaic representing a slight gradient of urbanization. Environmental variables encompassed plot- and patch-level measurements and a climatic matrix, while principal coordinates of neighbor matrices (PCNMs) acted as spatial variables. A forward selection procedure was carried out to select environmental and spatial variables influencing web-spider beta diversity. Variation partitioning was used to estimate the contribution of pure environmental and pure spatial effects and their shared influence on beta-diversity patterns, and to estimate the relative importance of selected environmental variables. Three environmental variables (bush density, land use in the surroundings of patches, and shape of patches) and two spatial variables were selected by forward selection procedures. Variation partitioning revealed that 15% of the variation of beta diversity was explained by a combination of environmental and PCNM variables. Most of this variation (12%) corresponded to pure environmental and spatially environmental structure. The data indicated that (1) spatial legacy was not important in explaining the web-spider beta diversity; (2) environmental predictors explained a significant portion of the variation in web-spider composition; (3) one-third of environmental variation was due to a spatial structure that jointly explains variation in species distributions. We were able to detect important factors related to matrix management influencing the web-spider beta-diversity patterns, which are probably linked to historical deforestation events.

CONSTRAINTS ON SPATIAL VARIATIONS IN THE FINE-STRUCTURE CONSTANT FROM PLANCK

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

O'Bryan, Jon; Smidt, Joseph; De Bernardis, Francesco

2015-01-01

We use the cosmic microwave background (CMB) anisotropy data from Planck to constrain the spatial fluctuations of the fine-structure constant α at a redshift of 1100. We use a quadratic estimator to measure the four-point correlation function of the CMB temperature anisotropies and extract the angular power spectrum fine-structure constant spatial variations projected along the line of sight at the last scattering surface. At tens of degree angular scales and above, we constrain the fractional rms fluctuations of the fine-structure constant to be (δα/α){sub rms} < 3.4 × 10{sup –3} at the 68% confidence level. We find no evidence formore » a spatially varying α at a redshift of 10{sup 3}.« less

Structural geology practice and learning, from the perspective of cognitive science

NASA Astrophysics Data System (ADS)

Shipley, Thomas F.; Tikoff, Basil; Ormand, Carol; Manduca, Cathy

2013-09-01

Spatial ability is required by practitioners and students of structural geology and so, considering spatial skills in the context of cognitive science has the potential to improve structural geology teaching and practice. Spatial thinking skills may be organized using three dichotomies, which can be linked to structural geology practice. First, a distinction is made between separating (attending to part of a whole) and combining (linking together aspects of the whole). While everyone has a basic ability to separate and combine, experts attend to differences guided by experiences of rock properties in context. Second, a distinction is made between seeing the relations among multiple objects as separate items or the relations within a single object with multiple parts. Experts can flexibly consider relations among or between objects to optimally reason about different types of spatial problems. Third, a distinction is made between reasoning about stationary and moving objects. Experts recognize static configurations that encode a movement history, and create mental models of the processes that led to the static state. The observations and inferences made by a geologist leading a field trip are compared with the corresponding observations and inferences made by a cognitive psychologist interested in spatial learning. The presented framework provides a vocabulary for discussing spatial skills both within and between the fields of structural geology and cognitive psychology.

Snow depth spatial structure from hillslope to basin scale

NASA Astrophysics Data System (ADS)

Deems, J. S.

2017-12-01

Knowledge of spatial patterns of snow accumulation is required for understanding the hydrology, climatology, and ecology of mountain regions. Spatial structure in snow accumulation patterns changes with the scale of observation, a feature that has been characterized using fractal dimensions calculated from lidar-derived snow depth maps: fractal scaling structure at short length scales, with a `scale break' transition to more stochastic patterns at longer separation distances. Previous work has shown that this fractal structure of snow depth distributions differs between sites with different vegetation and terrain characteristics. Forested areas showed a transition to a nearly random spatial distribution at a much shorter lag distance than do unforested sites, enabling a statistical characterization. Alpine areas, however, showed strong spatial structure for a much wider scale range, and were the source of the dominant spatial pattern observable over a wider area. These spatial structure characteristics suggest that the choice of measurement or model resolution (satellite sensor, DEM, field survey point spacing, etc.) will strongly affect the estimates of snow volume or mass, as well as the magnitude of spatial variability. These prior efforts used data sets that were high resolution ( 1 m laser point spacing) but of limited extent ( 1 km2), constraining detection of scale features such as fractal dimension or scale breaks to areas of relatively similar characteristics and to lag distances of under 500 m. New datasets available from the NASA JPL Airborne Snow Observatory (ASO) provide similar resolution but over large areas, enabling assessment of snow spatial structure across an entire watershed, or in similar vegetation or physiography but in different parts of the basin. Additionally, the multi-year ASO time series allows an investigation into the temporal stability of these scale characteristics, within a single snow season and between seasons of strongly varying accumulation totals and patterns. This presentation will explore initial results from this study, using data from the Tuolumne River Basin in California, USA. Fractal scaling characteristics derived from ASO lidar snow depth measurements are examined at the basin scale, as well as in varying topographic and forest cover environments.

Bring out your dead!: A study of income inequality and life expectancy in the United States, 2000-2010.

PubMed

Hill, Terrence D; Jorgenson, Andrew

2018-01-01

We test whether income inequality undermines female and male life expectancy in the United States. We employ data for all 50 states and the District of Columbia and two-way fixed effects to model state-level average life expectancy as a function of multiple income inequality measures and time-varying characteristics. We find that state-level income inequality is inversely associated with female and male life expectancy. We observe this general pattern across four measures of income inequality and under the rigorous conditions of state-specific and year-specific fixed effects. If income inequality undermines life expectancy, redistribution policies could actually improve the health of states. Copyright © 2017 Elsevier Ltd. All rights reserved.

Moving forward: response to "Studying eyewitness investigations in the field".

PubMed

Ross, Stephen J; Malpass, Roy S

2008-02-01

Field studies of eyewitness identification are richly confounded. Determining which confounds undermine interpretation is important. The blind administration confound in the Illinois study is said to undermine it's value for understanding the relative utility of simultaneous and sequential lineups. Most criticisms of the Illinois study focus on filler identifications, and related inferences about the importance of the blind confound. We find no convincing evidence supporting this line of attack and wonder at filler identifications as the major line of criticism. More debilitating problems impede using the Illinois study to address the simultaneous versus sequential lineup controversy: inability to estimate guilt independent of identification evidence, lack of protocol compliance monitoring, and assessment of lineups quality. Moving forward requires removing these limitations.

Spatial Visualization Tasks to Support Students' Spatial Structuring in Learning Volume Measurement

ERIC Educational Resources Information Center

Revina, Shintia; Zulkardi; Darmawijoyo; van Galen, Frans

2011-01-01

Many prior researches found that most of students in grade five tended to have difficulty in fully grasping the concept of volume measurement because they have to build their competence in spatial structuring. The unit of volume "packing" measurement must be integrated and coordinated in three-dimension. On the other hand, it is revealed…

Cheetahs and wild dogs show contrasting patterns of suppression by lions.

PubMed

Swanson, Alexandra; Caro, Tim; Davies-Mostert, Harriet; Mills, Michael G L; Macdonald, David W; Borner, Markus; Masenga, Emmanuel; Packer, Craig

2014-11-01

Top predators can dramatically suppress populations of smaller predators, with cascading effects throughout communities, and this pressure is often unquestioningly accepted as a constraint on mesopredator populations. In this study, we reassess whether African lions suppress populations of cheetahs and African wild dogs and examine possible mechanisms for coexistence between these species. Using long-term records from Serengeti National Park, we tested 30 years of population data for evidence of mesopredator suppression, and we examined six years of concurrent radio-telemetry data for evidence of large-scale spatial displacement. The Serengeti lion population nearly tripled between 1966 and 1998; during this time, wild dogs declined but cheetah numbers remained largely unchanged. Prior to their local extinction, wild dogs primarily occupied low lion density areas and apparently abandoned the long-term study area as the lion population 'saturated' the region. In contrast, cheetahs mostly utilized areas of high lion density, and the stability of the cheetah population indicates that neither high levels of lion-inflicted mortality nor behavioural avoidance inflict sufficient demographic consequences to translate into population-level effects. Population data from fenced reserves in southern Africa revealed a similar contrast between wild dogs and cheetahs in their ability to coexist with lions. These findings demonstrate differential responses of subordinate species within the same guild and challenge a widespread perception that lions undermine cheetah conservation efforts. Paired with several recent studies that document fine-scale lion-avoidance by cheetahs, this study further highlights fine-scale spatial avoidance as a possible mechanism for mitigating mesopredator suppression. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Spatial Variation in Background Mortality among Dominant Coral Taxa on Australia's Great Barrier Reef

PubMed Central

Pisapia, Chiara; Pratchett, Morgan S.

2014-01-01

Even in the absence of major disturbances (e.g., cyclones, bleaching), corals are consistently subject to high levels of background mortality, which undermines individual fitness and resilience of coral colonies. Partial mortality may impact coral response to climate change by reducing colony ability to recover between major acute stressors. This study quantified proportion of injured versus uninjured colonies (the prevalence of injuries) and instantaneous measures of areal extent of injuries across individual colonies (the severity of injuries), in four common coral species along the Great Barrier Reef in Australia: massive Porites, encrusting Montipora, Acropora hyacinthus and Pocillopora damicornis. A total of 2,276 adult colonies were surveyed three latitudinal sectors, nine reefs and 27 sites along 1000 km2 on the Great Barrier Reef. The prevalence of injuries was very high, especially for Porites spp (91%) and Montipora encrusting (85%) and varied significantly, but most lay at small spatial scales (e.g., among colonies positioned <10-m apart). Similarly, severity of background partial mortality was surprisingly high (between 5% and 21%) but varied greatly among colonies within the same site and habitat. This study suggests that intraspecific variation in partial mortality between adjacent colonies may be more important than variation between colonies in different latitudinal sectors or reefs. Differences in the prevalence and severity of background partial mortality have significant ramifications for coral capacity to cope with increasing acute disturbances, such as climate-induced coral bleaching. These data are important for understanding coral responses to increasing stressors, and in particular for predicting their capacity to recover between subsequent disturbances. PMID:24959921

The beneficial influence of inattention on visual interference in schizophrenia.

PubMed

Brodeur, Mathieu B; Kiang, Michael; Christensen, Bruce K

2016-09-01

Schizophrenia is associated with poor spatial attention. However, although this deficit undermines the perception of target information, it may be helpful for ignoring irrelevant inputs. The present study examined whether event-related brain potential (ERP) indices of visual spatial attention predicted the magnitude of the brain response to interference in schizophrenia. ERPs were recorded in 16 schizophrenia patients and 20 healthy control participants who had to indicate whether the target E was global or local in compound letter stimuli. The nontarget could be either highly similar to the target (i.e., a global E composed of local Ss and vice versa) and thus produce more interference, or it could be dissimilar (i.e., a global E composed of local Hs and vice versa) and generate less interference. Both groups' responses were slowed by interference. Voltage amplitudes of the P1, and of ERP interference effects from 300-500 ms after stimulus onset, were significantly smaller in schizophrenia patients than in healthy participants when the target was global. In patients, larger P1 amplitudes were correlated with larger interference effects and with more severe symptoms of attentional deficits and conceptual disorganization. Schizophrenia participants thus exhibited abnormal ERPs to interference despite normal behavioral performance. Schizophrenia patients likely pay less attention to stimuli in general; however, the impact of this impairment on target detection is compensated by relatively greater inattention to irrelevant components of the stimuli, and this explains why they are not more influenced by interference than healthy participants at the behavioral level. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Linking freshwater fishery management to global food security and biodiversity conservation.

PubMed

McIntyre, Peter B; Reidy Liermann, Catherine A; Revenga, Carmen

2016-10-24

Fisheries are an essential ecosystem service, but catches from freshwaters are often overlooked. Hundreds of millions of people around the world benefit from low-cost protein, recreation, and commerce provided by freshwater fisheries, particularly in regions where alternative sources of nutrition and employment are scarce. Here, we derive a gridded global map of riverine fisheries and assess its implications for biodiversity conservation, fishery sustainability, and food security. Catches increase with river discharge and human population density, and 90% of global catch comes from river basins with above-average stress levels. Fish richness and catches are positively but not causally correlated, revealing that fishing pressure is most intense in rivers where potential impacts on biodiversity are highest. Merging our catch analysis with nutritional and socioeconomic data, we find that freshwater fisheries provide the equivalent of all dietary animal protein for 158 million people. Poor and undernourished populations are particularly reliant on inland fisheries compared with marine or aquaculture sources. The spatial coincidence of productive freshwater fisheries and low food security highlights the critical role of rivers and lakes in providing locally sourced, low-cost protein. At the same time, intensive fishing in regions where rivers are already degraded by other stressors may undermine efforts to conserve biodiversity. This syndrome of poverty, nutritional deficiency, fishery dependence, and extrinsic threats to biodiverse river ecosystems underscores the high stakes for improving fishery management. Our enhanced spatial data on estimated catches can facilitate the inclusion of inland fisheries in environmental planning to protect both food security and species diversity.

Linking freshwater fishery management to global food security and biodiversity conservation

PubMed Central

McIntyre, Peter B.; Reidy Liermann, Catherine A.; Revenga, Carmen

2016-01-01

Fisheries are an essential ecosystem service, but catches from freshwaters are often overlooked. Hundreds of millions of people around the world benefit from low-cost protein, recreation, and commerce provided by freshwater fisheries, particularly in regions where alternative sources of nutrition and employment are scarce. Here, we derive a gridded global map of riverine fisheries and assess its implications for biodiversity conservation, fishery sustainability, and food security. Catches increase with river discharge and human population density, and 90% of global catch comes from river basins with above-average stress levels. Fish richness and catches are positively but not causally correlated, revealing that fishing pressure is most intense in rivers where potential impacts on biodiversity are highest. Merging our catch analysis with nutritional and socioeconomic data, we find that freshwater fisheries provide the equivalent of all dietary animal protein for 158 million people. Poor and undernourished populations are particularly reliant on inland fisheries compared with marine or aquaculture sources. The spatial coincidence of productive freshwater fisheries and low food security highlights the critical role of rivers and lakes in providing locally sourced, low-cost protein. At the same time, intensive fishing in regions where rivers are already degraded by other stressors may undermine efforts to conserve biodiversity. This syndrome of poverty, nutritional deficiency, fishery dependence, and extrinsic threats to biodiverse river ecosystems underscores the high stakes for improving fishery management. Our enhanced spatial data on estimated catches can facilitate the inclusion of inland fisheries in environmental planning to protect both food security and species diversity. PMID:27791055

Spatial variation in background mortality among dominant coral taxa on Australia's Great Barrier Reef.

PubMed

Pisapia, Chiara; Pratchett, Morgan S

2014-01-01

Even in the absence of major disturbances (e.g., cyclones, bleaching), corals are consistently subject to high levels of background mortality, which undermines individual fitness and resilience of coral colonies. Partial mortality may impact coral response to climate change by reducing colony ability to recover between major acute stressors. This study quantified proportion of injured versus uninjured colonies (the prevalence of injuries) and instantaneous measures of areal extent of injuries across individual colonies (the severity of injuries), in four common coral species along the Great Barrier Reef in Australia: massive Porites, encrusting Montipora, Acropora hyacinthus and Pocillopora damicornis. A total of 2,276 adult colonies were surveyed three latitudinal sectors, nine reefs and 27 sites along 1000 km2 on the Great Barrier Reef. The prevalence of injuries was very high, especially for Porites spp (91%) and Montipora encrusting (85%) and varied significantly, but most lay at small spatial scales (e.g., among colonies positioned <10-m apart). Similarly, severity of background partial mortality was surprisingly high (between 5% and 21%) but varied greatly among colonies within the same site and habitat. This study suggests that intraspecific variation in partial mortality between adjacent colonies may be more important than variation between colonies in different latitudinal sectors or reefs. Differences in the prevalence and severity of background partial mortality have significant ramifications for coral capacity to cope with increasing acute disturbances, such as climate-induced coral bleaching. These data are important for understanding coral responses to increasing stressors, and in particular for predicting their capacity to recover between subsequent disturbances.

Spatial education: improving conservation delivery through space-structured decision making

USGS Publications Warehouse

Moore, Clinton T.; Shaffer, Terry L.; Gannon, Jill J.

2013-01-01

Adaptive management is a form of structured decision making designed to guide management of natural resource systems when their behaviors are uncertain. Where decision making can be replicated across units of a landscape, learning can be accelerated, and biological processes can be understood in a larger spatial context. Broad-based partnerships among land management agencies, exemplified by Landscape Conservation Cooperatives (conservation partnerships created through the U.S. Department of the Interior), are potentially ideal environments for implementing spatially structured adaptive management programs.

Super-resolution optical microscopy for studying membrane structure and dynamics.

PubMed

Sezgin, Erdinc

2017-07-12

Investigation of cell membrane structure and dynamics requires high spatial and temporal resolution. The spatial resolution of conventional light microscopy is limited due to the diffraction of light. However, recent developments in microscopy enabled us to access the nano-scale regime spatially, thus to elucidate the nanoscopic structures in the cellular membranes. In this review, we will explain the resolution limit, address the working principles of the most commonly used super-resolution microscopy techniques and summarise their recent applications in the biomembrane field.

Hippocampal-prefrontal input supports spatial encoding in working memory.

PubMed

Spellman, Timothy; Rigotti, Mattia; Ahmari, Susanne E; Fusi, Stefano; Gogos, Joseph A; Gordon, Joshua A

2015-06-18

Spatial working memory, the caching of behaviourally relevant spatial cues on a timescale of seconds, is a fundamental constituent of cognition. Although the prefrontal cortex and hippocampus are known to contribute jointly to successful spatial working memory, the anatomical pathway and temporal window for the interaction of these structures critical to spatial working memory has not yet been established. Here we find that direct hippocampal-prefrontal afferents are critical for encoding, but not for maintenance or retrieval, of spatial cues in mice. These cues are represented by the activity of individual prefrontal units in a manner that is dependent on hippocampal input only during the cue-encoding phase of a spatial working memory task. Successful encoding of these cues appears to be mediated by gamma-frequency synchrony between the two structures. These findings indicate a critical role for the direct hippocampal-prefrontal afferent pathway in the continuous updating of task-related spatial information during spatial working memory.

The rural-urban effect on spatial genetic structure of type II Toxoplasma gondii strains involved in human congenital toxoplasmosis, France, 2002-2009.

PubMed

Ajzenberg, Daniel; Collinet, Frédéric; Aubert, Dominique; Villena, Isabelle; Dardé, Marie-Laure; Devillard, Sébastien

2015-12-01

Congenital toxoplasmosis involves Toxoplasma gondii type II strains in 95% of cases in France. We used spatial principal component analysis (sPCA) and 15 microsatellite markers to investigate the spatial genetic structure of type II strains involved in 240 cases of congenital toxoplasmosis in France from 2002 through 2009. Mailing addresses of patients were geo-referenced a posteriori in decimal degrees and categorized into urban or rural areas of residence. No spatial genetic structure was found for type II strains that infected mothers who were living in urban areas, but a global spatial genetic structure was found for those that infected mothers who were living in a rural environment. Our results suggest that sources of infection by T. gondii are different in rural and urban areas in France, and advocate for targeted messages in the prevention of toxoplasmosis according to the type of residence of susceptible people. Copyright © 2015 Elsevier B.V. All rights reserved.

a Robust Descriptor Based on Spatial and Frequency Structural Information for Visible and Thermal Infrared Image Matching

NASA Astrophysics Data System (ADS)

Fu, Z.; Qin, Q.; Wu, C.; Chang, Y.; Luo, B.

2017-09-01

Due to the differences of imaging principles, image matching between visible and thermal infrared images still exist new challenges and difficulties. Inspired by the complementary spatial and frequency information of geometric structural features, a robust descriptor is proposed for visible and thermal infrared images matching. We first divide two different spatial regions to the region around point of interest, using the histogram of oriented magnitudes, which corresponds to the 2-D structural shape information to describe the larger region and the edge oriented histogram to describe the spatial distribution for the smaller region. Then the two vectors are normalized and combined to a higher feature vector. Finally, our proposed descriptor is obtained by applying principal component analysis (PCA) to reduce the dimension of the combined high feature vector to make our descriptor more robust. Experimental results showed that our proposed method was provided with significant improvements in correct matching numbers and obvious advantages by complementing information within spatial and frequency structural information.

Autoregressive modelling of species richness in the Brazilian Cerrado.

PubMed

Vieira, C M; Blamires, D; Diniz-Filho, J A F; Bini, L M; Rangel, T F L V B

2008-05-01

Spatial autocorrelation is the lack of independence between pairs of observations at given distances within a geographical space, a phenomenon commonly found in ecological data. Taking into account spatial autocorrelation when evaluating problems in geographical ecology, including gradients in species richness, is important to describe both the spatial structure in data and to correct the bias in Type I errors of standard statistical analyses. However, to effectively solve these problems it is necessary to establish the best way to incorporate the spatial structure to be used in the models. In this paper, we applied autoregressive models based on different types of connections and distances between 181 cells covering the Cerrado region of Central Brazil to study the spatial variation in mammal and bird species richness across the biome. Spatial structure was stronger for birds than for mammals, with R(2) values ranging from 0.77 to 0.94 for mammals and from 0.77 to 0.97 for birds, for models based on different definitions of spatial structures. According to the Akaike Information Criterion (AIC), the best autoregressive model was obtained by using the rook connection. In general, these results furnish guidelines for future modelling of species richness patterns in relation to environmental predictors and other variables expressing human occupation in the biome.

Using Common Spatial Distributions of Atoms to Relate Functionally Divergent Influenza Virus N10 and N11 Protein Structures to Functionally Characterized Neuraminidase Structures, Toxin Cell Entry Domains, and Non-Influenza Virus Cell Entry Domains

PubMed Central

Weininger, Arthur; Weininger, Susan

2015-01-01

The ability to identify the functional correlates of structural and sequence variation in proteins is a critical capability. We related structures of influenza A N10 and N11 proteins that have no established function to structures of proteins with known function by identifying spatially conserved atoms. We identified atoms with common distributed spatial occupancy in PDB structures of N10 protein, N11 protein, an influenza A neuraminidase, an influenza B neuraminidase, and a bacterial neuraminidase. By superposing these spatially conserved atoms, we aligned the structures and associated molecules. We report spatially and sequence invariant residues in the aligned structures. Spatially invariant residues in the N6 and influenza B neuraminidase active sites were found in previously unidentified spatially equivalent sites in the N10 and N11 proteins. We found the corresponding secondary and tertiary structures of the aligned proteins to be largely identical despite significant sequence divergence. We found structural precedent in known non-neuraminidase structures for residues exhibiting structural and sequence divergence in the aligned structures. In N10 protein, we identified staphylococcal enterotoxin I-like domains. In N11 protein, we identified hepatitis E E2S-like domains, SARS spike protein-like domains, and toxin components shared by alpha-bungarotoxin, staphylococcal enterotoxin I, anthrax lethal factor, clostridium botulinum neurotoxin, and clostridium tetanus toxin. The presence of active site components common to the N6, influenza B, and S. pneumoniae neuraminidases in the N10 and N11 proteins, combined with the absence of apparent neuraminidase function, suggests that the role of neuraminidases in H17N10 and H18N11 emerging influenza A viruses may have changed. The presentation of E2S-like, SARS spike protein-like, or toxin-like domains by the N10 and N11 proteins in these emerging viruses may indicate that H17N10 and H18N11 sialidase-facilitated cell entry has been supplemented or replaced by sialidase-independent receptor binding to an expanded cell population that may include neurons and T-cells. PMID:25706124

Effects of spatial resolution and landscape structure on land cover characterization

NASA Astrophysics Data System (ADS)

Yang, Wenli

This dissertation addressed problems in scaling, problems that are among the main challenges in remote sensing. The principal objective of the research was to investigate the effects of changing spatial scale on the representation of land cover. A second objective was to determine the relationship between such effects, characteristics of landscape structure and scaling procedures. Four research issues related to spatial scaling were examined. They included: (1) the upscaling of Normalized Difference Vegetation Index (NDVI); (2) the effects of spatial scale on indices of landscape structure; (3) the representation of land cover databases at different spatial scales; and (4) the relationships between landscape indices and land cover area estimations. The overall bias resulting from non-linearity of NDVI in relation to spatial resolution is generally insignificant as compared to other factors such as influences of aerosols and water vapor. The bias is, however, related to land surface characteristics. Significant errors may be introduced in heterogeneous areas where different land cover types exhibit strong spectral contrast. Spatially upscaled SPOT and TM NDVIs have information content comparable with the AVHRR-derived NDVI. Indices of landscape structure and spatial resolution are generally related, but the exact forms of the relationships are subject to changes in other factors including the basic patch unit constituting a landscape and the proportional area of foreground land cover under consideration. The extent of agreement between spatially aggregated coarse resolution land cover datasets and full resolution datasets changes with the properties of the original datasets, including the pixel size and class definition. There are close relationships between landscape structure and class areas estimated from spatially aggregated land cover databases. The relationships, however, do not permit extension from one area to another. Inversion calibration across different geographic/ecological areas is, therefore, not feasible. Different rules govern the land cover area changes across resolutions when different upscaling methods are used. Special attention should be given to comparison between land cover maps derived using different methods.

Dissecting the multi-scale spatial relationship of earthworm assemblages with soil environmental variability.

PubMed

Jiménez, Juan J; Decaëns, Thibaud; Lavelle, Patrick; Rossi, Jean-Pierre

2014-12-05

Studying the drivers and determinants of species, population and community spatial patterns is central to ecology. The observed structure of community assemblages is the result of deterministic abiotic (environmental constraints) and biotic factors (positive and negative species interactions), as well as stochastic colonization events (historical contingency). We analyzed the role of multi-scale spatial component of soil environmental variability in structuring earthworm assemblages in a gallery forest from the Colombian "Llanos". We aimed to disentangle the spatial scales at which species assemblages are structured and determine whether these scales matched those expressed by soil environmental variables. We also tested the hypothesis of the "single tree effect" by exploring the spatial relationships between root-related variables and soil nutrient and physical variables in structuring earthworm assemblages. Multivariate ordination techniques and spatially explicit tools were used, namely cross-correlograms, Principal Coordinates of Neighbor Matrices (PCNM) and variation partitioning analyses. The relationship between the spatial organization of earthworm assemblages and soil environmental parameters revealed explicitly multi-scale responses. The soil environmental variables that explained nested population structures across the multi-spatial scale gradient differed for earthworms and assemblages at the very-fine- (<10 m) to medium-scale (10-20 m). The root traits were correlated with areas of high soil nutrient contents at a depth of 0-5 cm. Information on the scales of PCNM variables was obtained using variogram modeling. Based on the size of the plot, the PCNM variables were arbitrarily allocated to medium (>30 m), fine (10-20 m) and very fine scales (<10 m). Variation partitioning analysis revealed that the soil environmental variability explained from less than 1% to as much as 48% of the observed earthworm spatial variation. A large proportion of the spatial variation did not depend on the soil environmental variability for certain species. This finding could indicate the influence of contagious biotic interactions, stochastic factors, or unmeasured relevant soil environmental variables.

The Voronoi spatio-temporal data structure

NASA Astrophysics Data System (ADS)

Mioc, Darka

2002-04-01

Current GIS models cannot integrate the temporal dimension of spatial data easily. Indeed, current GISs do not support incremental (local) addition and deletion of spatial objects, and they can not support the temporal evolution of spatial data. Spatio-temporal facilities would be very useful in many GIS applications: harvesting and forest planning, cadastre, urban and regional planning, and emergency planning. The spatio-temporal model that can overcome these problems is based on a topological model---the Voronoi data structure. Voronoi diagrams are irregular tessellations of space, that adapt to spatial objects and therefore they are a synthesis of raster and vector spatial data models. The main advantage of the Voronoi data structure is its local and sequential map updates, which allows us to automatically record each event and performed map updates within the system. These map updates are executed through map construction commands that are composed of atomic actions (geometric algorithms for addition, deletion, and motion of spatial objects) on the dynamic Voronoi data structure. The formalization of map commands led to the development of a spatial language comprising a set of atomic operations or constructs on spatial primitives (points and lines), powerful enough to define the complex operations. This resulted in a new formal model for spatio-temporal change representation, where each update is uniquely characterized by the numbers of newly created and inactivated Voronoi regions. This is used for the extension of the model towards the hierarchical Voronoi data structure. In this model, spatio-temporal changes induced by map updates are preserved in a hierarchical data structure that combines events and corresponding changes in topology. This hierarchical Voronoi data structure has an implicit time ordering of events visible through changes in topology, and it is equivalent to an event structure that can support temporal data without precise temporal information. This formal model of spatio-temporal change representation is currently applied to retroactive map updates and visualization of map evolution. It offers new possibilities in the domains of temporal GIS, transaction processing, spatio-temporal queries, spatio-temporal analysis, map animation and map visualization.

Local overfishing may be avoided by examining parameters of a spatio-temporal model

PubMed Central

Shackell, Nancy; Mills Flemming, Joanna

2017-01-01

Spatial erosion of stock structure through local overfishing can lead to stock collapse because fish often prefer certain locations, and fisheries tend to focus on those locations. Fishery managers are challenged to maintain the integrity of the entire stock and require scientific approaches that provide them with sound advice. Here we propose a Bayesian hierarchical spatio-temporal modelling framework for fish abundance data to estimate key parameters that define spatial stock structure: persistence (similarity of spatial structure over time), connectivity (coherence of temporal pattern over space), and spatial variance (variation across the seascape). The consideration of these spatial parameters in the stock assessment process can help identify the erosion of structure and assist in preventing local overfishing. We use Atlantic cod (Gadus morhua) in eastern Canada as a case study an examine the behaviour of these parameters from the height of the fishery through its collapse. We identify clear signals in parameter behaviour under circumstances of destructive stock erosion as well as for recovery of spatial structure even when combined with a non-recovery in abundance. Further, our model reveals the spatial pattern of areas of high and low density persists over the 41 years of available data and identifies the remnant patches. Models of this sort are crucial to recovery plans if we are to identify and protect remaining sources of recolonization for Atlantic cod. Our method is immediately applicable to other exploited species. PMID:28886179

Local overfishing may be avoided by examining parameters of a spatio-temporal model.

PubMed

Carson, Stuart; Shackell, Nancy; Mills Flemming, Joanna

2017-01-01

Spatial erosion of stock structure through local overfishing can lead to stock collapse because fish often prefer certain locations, and fisheries tend to focus on those locations. Fishery managers are challenged to maintain the integrity of the entire stock and require scientific approaches that provide them with sound advice. Here we propose a Bayesian hierarchical spatio-temporal modelling framework for fish abundance data to estimate key parameters that define spatial stock structure: persistence (similarity of spatial structure over time), connectivity (coherence of temporal pattern over space), and spatial variance (variation across the seascape). The consideration of these spatial parameters in the stock assessment process can help identify the erosion of structure and assist in preventing local overfishing. We use Atlantic cod (Gadus morhua) in eastern Canada as a case study an examine the behaviour of these parameters from the height of the fishery through its collapse. We identify clear signals in parameter behaviour under circumstances of destructive stock erosion as well as for recovery of spatial structure even when combined with a non-recovery in abundance. Further, our model reveals the spatial pattern of areas of high and low density persists over the 41 years of available data and identifies the remnant patches. Models of this sort are crucial to recovery plans if we are to identify and protect remaining sources of recolonization for Atlantic cod. Our method is immediately applicable to other exploited species.

Medicine for the City: Perspective and Solidarity as Tools for Making Urban Health.

PubMed

Fullilove, Mindy Thompson; Cantal-Dupart, Michel

2016-06-01

The United States has pursued policies of urban upheaval that have undermined social organization, dispersed people, particularly African Americans, and increased rates of disease and disorder. Healthcare institutions have been, and can be, a part of this problem or a part of the solution. This essay addresses two tools that healthcare providers can use to repair the urban ecosystem-perspective and solidarity. Perspective addresses both our ability to envision solutions and our ability to see in the space in which we move. Solidarity is our ability to appreciate our fellowship with other people, a mindset that is at the heart of medical practice. These two tools lay the foundation for structurally competent healthcare providers to act in a restorative manner to create a health-giving built environment.

Building tolerance by dismantling synapses: inhibitory receptor signaling in natural killer cells.

PubMed

Huse, Morgan; Catherine Milanoski, S; Abeyweera, Thushara P

2013-01-01

Cell surface receptors bearing immunotyrosine-based inhibitory motifs (ITIMs) maintain natural killer (NK) cell tolerance to normal host tissues. These receptors are difficult to analyze mechanistically because they block activating responses in a rapid and comprehensive manner. The advent of high-resolution single cell imaging techniques has enabled investigators to explore the cell biological basis of the inhibitory response. Recent studies using these approaches indicate that ITIM-containing receptors function at least in part by structurally undermining the immunological synapse between the NK cell and its target. In this review, we discuss these new advances and how they might relate to what is known about the biochemistry of inhibitory signaling in NK cells and other cell types. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

Root Shock Revisited: Perspectives of Early Head Start Mothers on Community and Policy Environments and Their Effects on Child Health, Development, and School Readiness

PubMed Central

McAllister, Carol L.; Thomas, Tammy L.; Green, Beth L.

2009-01-01

Racial differences in school readiness are a form of health disparity. By examining, from the perspective of low-income minority families participating in an Early Head Start study, community and policy environments as they shape and inform lived experiences, we identified several types of social and economic dislocation that undermine the efforts of parents to ready their children for school. The multiple dislocations of community triggered by housing and welfare reform and “urban renewal” are sources of stress for parents and children and affect the health and development of young children. Our findings suggest that racial differences in school readiness result not from race but from poverty and structural racism in American society. PMID:19059871

Confronting safety gaps across labor and delivery teams.

PubMed

Maxfield, David G; Lyndon, Audrey; Kennedy, Holly Powell; O'Keeffe, Daniel F; Zlatnik, Marya G

2013-11-01

We assessed the occurrence of 4 safety concerns among labor and delivery teams: dangerous shortcuts, missing competencies, disrespect, and performance problems. A total of 3282 participants completed surveys, and 92% of physicians (906 of 985), 93% of midwives (385 of 414), and 98% of nurses (1846 of 1884) observed at least 1 concern within the preceding year. A majority of respondents said these concerns undermined patient safety, harmed patients, or led them to seriously consider transferring or leaving their positions. Only 9% of physicians, 13% of midwives, and 13% of nurses shared their full concerns with the person involved. Organizational silence is evident within labor-and-delivery teams. Improvement will require multiple strategies, used at the personal, social, and structural levels. Copyright © 2013 Mosby, Inc. All rights reserved.

A Spatial View of the Interpersonal Structure of Family Interviews: Similarities and Differences Across Counselors.

ERIC Educational Resources Information Center

Friedlander, Myrna L.; Highlen, Pamela S.

1984-01-01

Examined the interpersonal structures of interviews by Ackerman, Bowen, Jackson, and Whitaker with the same family to identify common features across counselors. Multidimensional scaling provided a spatial representation of the hidden structure in the communication patterns of these interviews. Correlations indicated counselors' interactions were…

Coupling fine-scale root and canopy structure using ground-based remote sensing

Treesearch

Brady Hardiman; Christopher Gough; John Butnor; Gil Bohrer; Matteo Detto; Peter Curtis

2017-01-01

Ecosystem physical structure, defined by the quantity and spatial distribution of biomass, influences a range of ecosystem functions. Remote sensing tools permit the non-destructive characterization of canopy and root features, potentially providing opportunities to link above- and belowground structure at fine spatial resolution in...

Phase Synchronization and Desynchronization of Structural Response Induced by Turbulent and External Sound

NASA Technical Reports Server (NTRS)

Maestrello, Lucio

2002-01-01

Acoustic and turbulent boundary layer flow loadings over a flexible structure are used to study the spatial-temporal dynamics of the response of the structure. The stability of the spatial synchronization and desynchronization by an active external force is investigated with an array of coupled transducers on the structure. In the synchronous state, the structural phase is locked, which leads to the formation of spatial patterns while the amplitude peaks exhibit chaotic behaviors. Large amplitude, spatially symmetric loading is superimposed on broadband, but in the desynchronized state, the spectrum broadens and the phase space is lost. The resulting pattern bears a striking resemblance to phase turbulence. The transition is achieved by using a low power external actuator to trigger broadband behaviors from the knowledge of the external acoustic load inducing synchronization. The changes are made favorably and efficiently to alter the frequency distribution of power, not the total power level. Before synchronization effects are seen, the panel response to the turbulent boundary layer loading is discontinuously spatio-temporally correlated. The stability develops from different competing wavelengths; the spatial scale is significantly shorter than when forced with the superimposed external sound. When the external sound level decreases and the synchronized phases are lost, changes in the character of the spectra can be linked to the occurrence of spatial phase transition. These changes can develop broadband response. Synchronized responses of fuselage structure panels have been observed in subsonic and supersonic aircraft; results from two flights tests are discussed.

Spatially explicit measurements of forest structure and fire behavior following restoration treatments in dry forests

Treesearch

Justin Paul Ziegler; Chad Hoffman; Michael Battaglia; William Mell

2017-01-01

Restoration treatments in dry forests of the western US often attempt silvicultural practices to restore the historical characteristics of forest structure and fire behavior. However, it is suggested that a reliance on non-spatial metrics of forest stand structure, along with the use of wildland fire behavior models that lack the ability to handle complex structures,...

Using temporal ICA to selectively remove global noise while preserving global signal in functional MRI data.

PubMed

Glasser, Matthew F; Coalson, Timothy S; Bijsterbosch, Janine D; Harrison, Samuel J; Harms, Michael P; Anticevic, Alan; Van Essen, David C; Smith, Stephen M

2018-06-02

Temporal fluctuations in functional Magnetic Resonance Imaging (fMRI) have been profitably used to study brain activity and connectivity for over two decades. Unfortunately, fMRI data also contain structured temporal "noise" from a variety of sources, including subject motion, subject physiology, and the MRI equipment. Recently, methods have been developed to automatically and selectively remove spatially specific structured noise from fMRI data using spatial Independent Components Analysis (ICA) and machine learning classifiers. Spatial ICA is particularly effective at removing spatially specific structured noise from high temporal and spatial resolution fMRI data of the type acquired by the Human Connectome Project and similar studies. However, spatial ICA is mathematically, by design, unable to separate spatially widespread "global" structured noise from fMRI data (e.g., blood flow modulations from subject respiration). No methods currently exist to selectively and completely remove global structured noise while retaining the global signal from neural activity. This has left the field in a quandary-to do or not to do global signal regression-given that both choices have substantial downsides. Here we show that temporal ICA can selectively segregate and remove global structured noise while retaining global neural signal in both task-based and resting state fMRI data. We compare the results before and after temporal ICA cleanup to those from global signal regression and show that temporal ICA cleanup removes the global positive biases caused by global physiological noise without inducing the network-specific negative biases of global signal regression. We believe that temporal ICA cleanup provides a "best of both worlds" solution to the global signal and global noise dilemma and that temporal ICA itself unlocks interesting neurobiological insights from fMRI data. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of spatial scale of sampling on food web structure

PubMed Central

Wood, Spencer A; Russell, Roly; Hanson, Dieta; Williams, Richard J; Dunne, Jennifer A

2015-01-01

This study asks whether the spatial scale of sampling alters structural properties of food webs and whether any differences are attributable to changes in species richness and connectance with scale. Understanding how different aspects of sampling effort affect ecological network structure is important for both fundamental ecological knowledge and the application of network analysis in conservation and management. Using a highly resolved food web for the marine intertidal ecosystem of the Sanak Archipelago in the Eastern Aleutian Islands, Alaska, we assess how commonly studied properties of network structure differ for 281 versions of the food web sampled at five levels of spatial scale representing six orders of magnitude in area spread across the archipelago. Species (S) and link (L) richness both increased by approximately one order of magnitude across the five spatial scales. Links per species (L/S) more than doubled, while connectance (C) decreased by approximately two-thirds. Fourteen commonly studied properties of network structure varied systematically with spatial scale of sampling, some increasing and others decreasing. While ecological network properties varied systematically with sampling extent, analyses using the niche model and a power-law scaling relationship indicate that for many properties, this apparent sensitivity is attributable to the increasing S and decreasing C of webs with increasing spatial scale. As long as effects of S and C are accounted for, areal sampling bias does not have a special impact on our understanding of many aspects of network structure. However, attention does need be paid to some properties such as the fraction of species in loops, which increases more than expected with greater spatial scales of sampling. PMID:26380704

Humanoid monocular stereo measuring system with two degrees of freedom using bionic optical imaging system

NASA Astrophysics Data System (ADS)

Du, Jia-Wei; Wang, Xuan-Yin; Zhu, Shi-Qiang

2017-10-01

Based on the process by which the spatial depth clue is obtained by a single eye, a monocular stereo vision to measure the depth information of spatial objects was proposed in this paper and a humanoid monocular stereo measuring system with two degrees of freedom was demonstrated. The proposed system can effectively obtain the three-dimensional (3-D) structure of spatial objects of different distances without changing the position of the system and has the advantages of being exquisite, smart, and flexible. The bionic optical imaging system we proposed in a previous paper, named ZJU SY-I, was employed and its vision characteristic was just like the resolution decay of the eye's vision from center to periphery. We simplified the eye's rotation in the eye socket and the coordinated rotation of other organs of the body into two rotations in the orthogonal direction and employed a rotating platform with two rotation degrees of freedom to drive ZJU SY-I. The structure of the proposed system was described in detail. The depth of a single feature point on the spatial object was deduced, as well as its spatial coordination. With the focal length adjustment of ZJU SY-I and the rotation control of the rotation platform, the spatial coordinates of all feature points on the spatial object could be obtained and then the 3-D structure of the spatial object could be reconstructed. The 3-D structure measurement experiments of two spatial objects with different distances and sizes were conducted. Some main factors affecting the measurement accuracy of the proposed system were analyzed and discussed.

Ecosystem variability along the estuarine salinity gradient: Examples from long-term study of San Francisco Bay

USGS Publications Warehouse

Cloern, James E.; Jassby, Alan D.; Schraga, Tara; Kress, Erica S.; Martin, Charles A.

2017-01-01

The salinity gradient of estuaries plays a unique and fundamental role in structuring spatial patterns of physical properties, biota, and biogeochemical processes. We use variability along the salinity gradient of San Francisco Bay to illustrate some lessons about the diversity of spatial structures in estuaries and their variability over time. Spatial patterns of dissolved constituents (e.g., silicate) can be linear or nonlinear, depending on the relative importance of river-ocean mixing and internal sinks (diatom uptake). Particles have different spatial patterns because they accumulate in estuarine turbidity maxima formed by the combination of sinking and estuarine circulation. Some constituents have weak or no mean spatial structure along the salinity gradient, reflecting spatially distributed sources along the estuary (nitrate) or atmospheric exchanges that buffer spatial variability of ecosystem metabolism (dissolved oxygen). The density difference between freshwater and seawater establishes stratification in estuaries stronger than the thermal stratification of lakes and oceans. Stratification is strongest around the center of the salinity gradient and when river discharge is high. Spatial distributions of motile organisms are shaped by species-specific adaptations to different salinity ranges (shrimp) and by behavioral responses to environmental variability (northern anchovy). Estuarine spatial patterns change over time scales of events (intrusions of upwelled ocean water), seasons (river inflow), years (annual weather anomalies), and between eras separated by ecosystem disturbances (a species introduction). Each of these lessons is a piece in the puzzle of how estuarine ecosystems are structured and how they differ from the river and ocean ecosystems they bridge.

Quantifying seascape structure: Extending terrestrial spatial pattern metrics to the marine realm

USGS Publications Warehouse

Wedding, L.M.; Christopher, L.A.; Pittman, S.J.; Friedlander, A.M.; Jorgensen, S.

2011-01-01

Spatial pattern metrics have routinely been applied to characterize and quantify structural features of terrestrial landscapes and have demonstrated great utility in landscape ecology and conservation planning. The important role of spatial structure in ecology and management is now commonly recognized, and recent advances in marine remote sensing technology have facilitated the application of spatial pattern metrics to the marine environment. However, it is not yet clear whether concepts, metrics, and statistical techniques developed for terrestrial ecosystems are relevant for marine species and seascapes. To address this gap in our knowledge, we reviewed, synthesized, and evaluated the utility and application of spatial pattern metrics in the marine science literature over the past 30 yr (1980 to 2010). In total, 23 studies characterized seascape structure, of which 17 quantified spatial patterns using a 2-dimensional patch-mosaic model and 5 used a continuously varying 3-dimensional surface model. Most seascape studies followed terrestrial-based studies in their search for ecological patterns and applied or modified existing metrics. Only 1 truly unique metric was found (hydrodynamic aperture applied to Pacific atolls). While there are still relatively few studies using spatial pattern metrics in the marine environment, they have suffered from similar misuse as reported for terrestrial studies, such as the lack of a priori considerations or the problem of collinearity between metrics. Spatial pattern metrics offer great potential for ecological research and environmental management in marine systems, and future studies should focus on (1) the dynamic boundary between the land and sea; (2) quantifying 3-dimensional spatial patterns; and (3) assessing and monitoring seascape change. ?? Inter-Research 2011.

Estimating temporal trend in the presence of spatial complexity: A Bayesian hierarchical model for a wetland plant population undergoing restoration

USGS Publications Warehouse

Rodhouse, T.J.; Irvine, K.M.; Vierling, K.T.; Vierling, L.A.

2011-01-01

Monitoring programs that evaluate restoration and inform adaptive management are important for addressing environmental degradation. These efforts may be well served by spatially explicit hierarchical approaches to modeling because of unavoidable spatial structure inherited from past land use patterns and other factors. We developed Bayesian hierarchical models to estimate trends from annual density counts observed in a spatially structured wetland forb (Camassia quamash [camas]) population following the cessation of grazing and mowing on the study area, and in a separate reference population of camas. The restoration site was bisected by roads and drainage ditches, resulting in distinct subpopulations ("zones") with different land use histories. We modeled this spatial structure by fitting zone-specific intercepts and slopes. We allowed spatial covariance parameters in the model to vary by zone, as in stratified kriging, accommodating anisotropy and improving computation and biological interpretation. Trend estimates provided evidence of a positive effect of passive restoration, and the strength of evidence was influenced by the amount of spatial structure in the model. Allowing trends to vary among zones and accounting for topographic heterogeneity increased precision of trend estimates. Accounting for spatial autocorrelation shifted parameter coefficients in ways that varied among zones depending on strength of statistical shrinkage, autocorrelation and topographic heterogeneity-a phenomenon not widely described. Spatially explicit estimates of trend from hierarchical models will generally be more useful to land managers than pooled regional estimates and provide more realistic assessments of uncertainty. The ability to grapple with historical contingency is an appealing benefit of this approach.

A spatial analysis of hierarchical waste transport structures under growing demand.

PubMed

Tanguy, Audrey; Glaus, Mathias; Laforest, Valérie; Villot, Jonathan; Hausler, Robert

2016-10-01

The design of waste management systems rarely accounts for the spatio-temporal evolution of the demand. However, recent studies suggest that this evolution affects the planning of waste management activities like the choice and location of treatment facilities. As a result, the transport structure could also be affected by these changes. The objective of this paper is to study the influence of the spatio-temporal evolution of the demand on the strategic planning of a waste transport structure. More particularly this study aims at evaluating the effect of varying spatial parameters on the economic performance of hierarchical structures (with one transfer station). To this end, three consecutive generations of three different spatial distributions were tested for hierarchical and non-hierarchical transport structures based on costs minimization. Results showed that a hierarchical structure is economically viable for large and clustered spatial distributions. The distance parameter was decisive but the loading ratio of trucks and the formation of clusters of sources also impacted the attractiveness of the transfer station. Thus the territories' morphology should influence strategies as regards to the installation of transfer stations. The use of spatial-explicit tools such as the transport model presented in this work that take into account the territory's evolution are needed to help waste managers in the strategic planning of waste transport structures. © The Author(s) 2016.

Novel probabilistic models of spatial genetic ancestry with applications to stratification correction in genome-wide association studies.

PubMed

Bhaskar, Anand; Javanmard, Adel; Courtade, Thomas A; Tse, David

2017-03-15

Genetic variation in human populations is influenced by geographic ancestry due to spatial locality in historical mating and migration patterns. Spatial population structure in genetic datasets has been traditionally analyzed using either model-free algorithms, such as principal components analysis (PCA) and multidimensional scaling, or using explicit spatial probabilistic models of allele frequency evolution. We develop a general probabilistic model and an associated inference algorithm that unify the model-based and data-driven approaches to visualizing and inferring population structure. Our spatial inference algorithm can also be effectively applied to the problem of population stratification in genome-wide association studies (GWAS), where hidden population structure can create fictitious associations when population ancestry is correlated with both the genotype and the trait. Our algorithm Geographic Ancestry Positioning (GAP) relates local genetic distances between samples to their spatial distances, and can be used for visually discerning population structure as well as accurately inferring the spatial origin of individuals on a two-dimensional continuum. On both simulated and several real datasets from diverse human populations, GAP exhibits substantially lower error in reconstructing spatial ancestry coordinates compared to PCA. We also develop an association test that uses the ancestry coordinates inferred by GAP to accurately account for ancestry-induced correlations in GWAS. Based on simulations and analysis of a dataset of 10 metabolic traits measured in a Northern Finland cohort, which is known to exhibit significant population structure, we find that our method has superior power to current approaches. Our software is available at https://github.com/anand-bhaskar/gap . abhaskar@stanford.edu or ajavanma@usc.edu. Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

Up, Down, and All Around: Scale-Dependent Spatial Variation in Rocky-Shore Communities of Fildes Peninsula, King George Island, Antarctica

PubMed Central

Valdivia, Nelson; Díaz, María J.; Holtheuer, Jorge; Garrido, Ignacio; Huovinen, Pirjo; Gómez, Iván

2014-01-01

Understanding the variation of biodiversity along environmental gradients and multiple spatial scales is relevant for theoretical and management purposes. Hereby, we analysed the spatial variability in diversity and structure of intertidal and subtidal macrobenthic Antarctic communities along vertical environmental stress gradients and across multiple horizontal spatial scales. Since biotic interactions and local topographic features are likely major factors for coastal assemblages, we tested the hypothesis that fine-scale processes influence the effects of the vertical environmental stress gradients on the macrobenthic diversity and structure. We used nested sampling designs in the intertidal and subtidal habitats, including horizontal spatial scales ranging from few centimetres to 1000s of metres along the rocky shore of Fildes Peninsula, King George Island. In both intertidal and subtidal habitats, univariate and multivariate analyses showed a marked vertical zonation in taxon richness and community structure. These patterns depended on the horizontal spatial scale of observation, as all analyses showed a significant interaction between height (or depth) and the finer spatial scale analysed. Variance and pseudo-variance components supported our prediction for taxon richness, community structure, and the abundance of dominant species such as the filamentous green alga Urospora penicilliformis (intertidal), the herbivore Nacella concinna (intertidal), the large kelp-like Himantothallus grandifolius (subtidal), and the red crustose red alga Lithothamnion spp. (subtidal). We suggest that in coastal ecosystems strongly governed by physical factors, fine-scale processes (e.g. biotic interactions and refugia availability) are still relevant for the structuring and maintenance of the local communities. The spatial patterns found in this study serve as a necessary benchmark to understand the dynamics and adaptation of natural assemblages in response to observed and predicted environmental changes in Antarctica. PMID:24956114

Circulation controls of the spatial structure of maximum daily precipitation over Poland

NASA Astrophysics Data System (ADS)

Stach, Alfred

2015-04-01

Among forecasts made on the basis of global and regional climatic models is one of a high probability of an increase in the frequency and intensity of extreme precipitation events. Learning the regularities underlying the recurrence and spatial extent of extreme precipitation is obviously of great importance, both economic and social. The main goal of the study was to analyse regularities underlying spatial and temporal variations in monthly Maximum Daily Precipitation Totals (MDPTs) observed in Poland over the years 1956-1980. These data are specific because apart from being spatially discontinuous, which is typical of precipitation, they are also non-synchronic. The main aim of the study was accomplished via several detailed goals: • identification and typology of the spatial structure of monthly MDPTs, • determination of the character and probable origin of events generating MDPTs, and • quantitative assessment of the contribution of the particular events to the overall MDPT figures. The analysis of the spatial structure of MDPTs was based on 300 models of spatial structure, one for each of the analysed sets of monthly MDPTs. The models were built on the basis of empirical anisotropic semivariograms of normalised data. In spite of their spatial discontinuity and asynchronicity, the MDPT data from Poland display marked regularities in their spatial pattern that yield readily to mathematical modelling. The MDPT field in Poland is usually the sum of the outcomes of three types of processes operating at various spatial scales: local (<10-20 km), regional (50-150 km), and supra-regional (>200 km). The spatial scales are probably connected with a convective/ orographic, a frontal and a 'planetary waves' genesis of high precipitation. Their contributions are highly variable. Generally predominant, however, are high daily precipitation totals with a spatial extent of 50 to 150 km connected with mesoscale phenomena and the migration of atmospheric fronts (35-38%). The spatial extent of areas of high local-scale precipitation usually varies at random, especially in the warm season. At supra-local scales, structures of repetitive size predominate. Eight types of anisotropic structures of monthly MDPTs were distinguished. To identify them, an analysis was made of semivariance surface similarities. The types differ not only in the level and direction of anisotropy, but also in the number and type of elementary components, which is evidence of genetic differences in precipitation. Their appearance shows a significant seasonal variability, so the most probable supposition was that temporal variations in the MDPT pattern were connected with circulation conditions: the type and direction of inflow of air masses. This hypothesis was validated by testing differences in the frequency of occurrence of Grosswetterlagen circulation situations in the months belonging to the distinguished types of the spatial MDPT pattern.

Spatial Patterns in Alternative States and Thresholds: A Missing Link for Management of Landscapes?

USDA-ARS?s Scientific Manuscript database

The detection of threshold dynamics (and other dynamics of interest) would benefit from explicit representations of spatial patterns of disturbance, spatial dependence in responses to disturbance, and the spatial structure of feedbacks in the design of monitoring and management strategies. Spatially...

Spatial Heterogeneity of Leaf Area Index (LAI) and Its Temporal Course on Arable Land: Combining Field Measurements, Remote Sensing and Simulation in a Comprehensive Data Analysis Approach (CDAA).

PubMed

Reichenau, Tim G; Korres, Wolfgang; Montzka, Carsten; Fiener, Peter; Wilken, Florian; Stadler, Anja; Waldhoff, Guido; Schneider, Karl

2016-01-01

The ratio of leaf area to ground area (leaf area index, LAI) is an important state variable in ecosystem studies since it influences fluxes of matter and energy between the land surface and the atmosphere. As a basis for generating temporally continuous and spatially distributed datasets of LAI, the current study contributes an analysis of its spatial variability and spatial structure. Soil-vegetation-atmosphere fluxes of water, carbon and energy are nonlinearly related to LAI. Therefore, its spatial heterogeneity, i.e., the combination of spatial variability and structure, has an effect on simulations of these fluxes. To assess LAI spatial heterogeneity, we apply a Comprehensive Data Analysis Approach that combines data from remote sensing (5 m resolution) and simulation (150 m resolution) with field measurements and a detailed land use map. Test area is the arable land in the fertile loess plain of the Rur catchment on the Germany-Belgium-Netherlands border. LAI from remote sensing and simulation compares well with field measurements. Based on the simulation results, we describe characteristic crop-specific temporal patterns of LAI spatial variability. By means of these patterns, we explain the complex multimodal frequency distributions of LAI in the remote sensing data. In the test area, variability between agricultural fields is higher than within fields. Therefore, spatial resolutions less than the 5 m of the remote sensing scenes are sufficient to infer LAI spatial variability. Frequency distributions from the simulation agree better with the multimodal distributions from remote sensing than normal distributions do. The spatial structure of LAI in the test area is dominated by a short distance referring to field sizes. Longer distances that refer to soil and weather can only be derived from remote sensing data. Therefore, simulations alone are not sufficient to characterize LAI spatial structure. It can be concluded that a comprehensive picture of LAI spatial heterogeneity and its temporal course can contribute to the development of an approach to create spatially distributed and temporally continuous datasets of LAI.

Spatial Heterogeneity of Leaf Area Index (LAI) and Its Temporal Course on Arable Land: Combining Field Measurements, Remote Sensing and Simulation in a Comprehensive Data Analysis Approach (CDAA)

PubMed Central

Korres, Wolfgang; Montzka, Carsten; Fiener, Peter; Wilken, Florian; Stadler, Anja; Waldhoff, Guido; Schneider, Karl

2016-01-01

The ratio of leaf area to ground area (leaf area index, LAI) is an important state variable in ecosystem studies since it influences fluxes of matter and energy between the land surface and the atmosphere. As a basis for generating temporally continuous and spatially distributed datasets of LAI, the current study contributes an analysis of its spatial variability and spatial structure. Soil-vegetation-atmosphere fluxes of water, carbon and energy are nonlinearly related to LAI. Therefore, its spatial heterogeneity, i.e., the combination of spatial variability and structure, has an effect on simulations of these fluxes. To assess LAI spatial heterogeneity, we apply a Comprehensive Data Analysis Approach that combines data from remote sensing (5 m resolution) and simulation (150 m resolution) with field measurements and a detailed land use map. Test area is the arable land in the fertile loess plain of the Rur catchment on the Germany-Belgium-Netherlands border. LAI from remote sensing and simulation compares well with field measurements. Based on the simulation results, we describe characteristic crop-specific temporal patterns of LAI spatial variability. By means of these patterns, we explain the complex multimodal frequency distributions of LAI in the remote sensing data. In the test area, variability between agricultural fields is higher than within fields. Therefore, spatial resolutions less than the 5 m of the remote sensing scenes are sufficient to infer LAI spatial variability. Frequency distributions from the simulation agree better with the multimodal distributions from remote sensing than normal distributions do. The spatial structure of LAI in the test area is dominated by a short distance referring to field sizes. Longer distances that refer to soil and weather can only be derived from remote sensing data. Therefore, simulations alone are not sufficient to characterize LAI spatial structure. It can be concluded that a comprehensive picture of LAI spatial heterogeneity and its temporal course can contribute to the development of an approach to create spatially distributed and temporally continuous datasets of LAI. PMID:27391858

Spatial transformation abilities and their relation to later mathematics performance.

PubMed

Frick, Andrea

2018-04-10

Using a longitudinal approach, this study investigated the relational structure of different spatial transformation skills at kindergarten age, and how these spatial skills relate to children's later mathematics performance. Children were tested at three time points, in kindergarten, first grade, and second grade (N = 119). Exploratory factor analyses revealed two subcomponents of spatial transformation skills: one representing egocentric transformations (mental rotation and spatial scaling), and one representing allocentric transformations (e.g., cross-sectioning, perspective taking). Structural equation modeling suggested that egocentric transformation skills showed their strongest relation to the part of the mathematics test tapping arithmetic operations, whereas allocentric transformations were strongly related to Numeric-Logical and Spatial Functions as well as geometry. The present findings point to a tight connection between early mental transformation skills, particularly the ones requiring a high level of spatial flexibility and a strong sense for spatial magnitudes, and children's mathematics performance at the beginning of their school career.

Quantifying Spatial Genetic Structuring in Mesophotic Populations of the Precious Coral Corallium rubrum

PubMed Central

Costantini, Federica; Carlesi, Lorenzo; Abbiati, Marco

2013-01-01

While shallow water red coral populations have been overharvested in the past, nowadays, commercial harvesting shifted its pressure on mesophotic organisms. An understanding of red coral population structure, particularly larval dispersal patterns and connectivity among harvested populations is paramount to the viability of the species. In order to determine patterns of genetic spatial structuring of deep water Corallium rubrum populations, for the first time, colonies found between 58–118 m depth within the Tyrrhenian Sea were collected and analyzed. Ten microsatellite loci and two regions of mitochondrial DNA (mtMSH and mtC) were used to quantify patterns of genetic diversity within populations and to define population structuring at spatial scales from tens of metres to hundreds of kilometres. Microsatellites showed heterozygote deficiencies in all populations. Significant levels of genetic differentiation were observed at all investigated spatial scales, suggesting that populations are likely to be isolated. This differentiation may by the results of biological interactions, occurring within a small spatial scale and/or abiotic factors acting at a larger scale. Mitochondrial markers revealed significant genetic structuring at spatial scales greater then 100 km showing the occurrence of a barrier to gene flow between northern and southern Tyrrhenian populations. These findings provide support for the establishment of marine protected areas in the deep sea and off-shore reefs, in order to effectively maintain genetic diversity of mesophotic red coral populations. PMID:23646109

Quantifying spatial genetic structuring in mesophotic populations of the precious coral Corallium rubrum.

PubMed

Costantini, Federica; Carlesi, Lorenzo; Abbiati, Marco

2013-01-01

While shallow water red coral populations have been overharvested in the past, nowadays, commercial harvesting shifted its pressure on mesophotic organisms. An understanding of red coral population structure, particularly larval dispersal patterns and connectivity among harvested populations is paramount to the viability of the species. In order to determine patterns of genetic spatial structuring of deep water Corallium rubrum populations, for the first time, colonies found between 58-118 m depth within the Tyrrhenian Sea were collected and analyzed. Ten microsatellite loci and two regions of mitochondrial DNA (mtMSH and mtC) were used to quantify patterns of genetic diversity within populations and to define population structuring at spatial scales from tens of metres to hundreds of kilometres. Microsatellites showed heterozygote deficiencies in all populations. Significant levels of genetic differentiation were observed at all investigated spatial scales, suggesting that populations are likely to be isolated. This differentiation may by the results of biological interactions, occurring within a small spatial scale and/or abiotic factors acting at a larger scale. Mitochondrial markers revealed significant genetic structuring at spatial scales greater then 100 km showing the occurrence of a barrier to gene flow between northern and southern Tyrrhenian populations. These findings provide support for the establishment of marine protected areas in the deep sea and off-shore reefs, in order to effectively maintain genetic diversity of mesophotic red coral populations.

Effects of Topography-based Subgrid Structures on Land Surface Modeling

NASA Astrophysics Data System (ADS)

Tesfa, T. K.; Ruby, L.; Brunke, M.; Thornton, P. E.; Zeng, X.; Ghan, S. J.

2017-12-01

Topography has major control on land surface processes through its influence on atmospheric forcing, soil and vegetation properties, network topology and drainage area. Consequently, accurate climate and land surface simulations in mountainous regions cannot be achieved without considering the effects of topographic spatial heterogeneity. To test a computationally less expensive hyper-resolution land surface modeling approach, we developed topography-based landunits within a hierarchical subgrid spatial structure to improve representation of land surface processes in the ACME Land Model (ALM) with minimal increase in computational demand, while improving the ability to capture the spatial heterogeneity of atmospheric forcing and land cover influenced by topography. This study focuses on evaluation of the impacts of the new spatial structures on modeling land surface processes. As a first step, we compare ALM simulations with and without subgrid topography and driven by grid cell mean atmospheric forcing to isolate the impacts of the subgrid topography on the simulated land surface states and fluxes. Recognizing that subgrid topography also has important effects on atmospheric processes that control temperature, radiation, and precipitation, methods are being developed to downscale atmospheric forcings. Hence in the second step, the impacts of the subgrid topographic structure on land surface modeling will be evaluated by including spatial downscaling of the atmospheric forcings. Preliminary results on the atmospheric downscaling and the effects of the new spatial structures on the ALM simulations will be presented.

Automation method to identify the geological structure of seabed using spatial statistic analysis of echo sounding data

NASA Astrophysics Data System (ADS)

Kwon, O.; Kim, W.; Kim, J.

2017-12-01

Recently construction of subsea tunnel has been increased globally. For safe construction of subsea tunnel, identifying the geological structure including fault at design and construction stage is more than important. Then unlike the tunnel in land, it's very difficult to obtain the data on geological structure because of the limit in geological survey. This study is intended to challenge such difficulties in a way of developing the technology to identify the geological structure of seabed automatically by using echo sounding data. When investigation a potential site for a deep subsea tunnel, there is the technical and economical limit with borehole of geophysical investigation. On the contrary, echo sounding data is easily obtainable while information reliability is higher comparing to above approaches. This study is aimed at developing the algorithm that identifies the large scale of geological structure of seabed using geostatic approach. This study is based on theory of structural geology that topographic features indicate geological structure. Basic concept of algorithm is outlined as follows; (1) convert the seabed topography to the grid data using echo sounding data, (2) apply the moving window in optimal size to the grid data, (3) estimate the spatial statistics of the grid data in the window area, (4) set the percentile standard of spatial statistics, (5) display the values satisfying the standard on the map, (6) visualize the geological structure on the map. The important elements in this study include optimal size of moving window, kinds of optimal spatial statistics and determination of optimal percentile standard. To determine such optimal elements, a numerous simulations were implemented. Eventually, user program based on R was developed using optimal analysis algorithm. The user program was designed to identify the variations of various spatial statistics. It leads to easy analysis of geological structure depending on variation of spatial statistics by arranging to easily designate the type of spatial statistics and percentile standard. This research was supported by the Korea Agency for Infrastructure Technology Advancement under the Ministry of Land, Infrastructure and Transport of the Korean government. (Project Number: 13 Construction Research T01)

Wide-field high spatial frequency domain imaging of tissue microstructure

NASA Astrophysics Data System (ADS)

Lin, Weihao; Zeng, Bixin; Cao, Zili; Zhu, Danfeng; Xu, M.

2018-02-01

Wide-field tissue imaging is usually not capable of resolving tissue microstructure. We present High Spatial Frequency Domain Imaging (HSFDI) - a noncontact imaging modality that spatially maps the tissue microscopic scattering structures over a large field of view. Based on an analytical reflectance model of sub-diffusive light from forward-peaked highly scattering media, HSFDI quantifies the spatially-resolved parameters of the light scattering phase function from the reflectance of structured light modulated at high spatial frequencies. We have demonstrated with ex vivo cancerous tissue to validate the robustness of HSFDI in significant contrast and differentiation of the microstructutral parameters between different types and disease states of tissue.

Spatial Cognition Support for Exploring the Design Mechanics of Building Structures

ERIC Educational Resources Information Center

Rudy, Margit; Hauck, Richard

2008-01-01

A web-based tool for visualizing the simulated structural behavior of building models was developed to support the teaching of structural design to architecture and engineering students by activating their spatial cognition capabilities. The main didactic issues involved establishing a consistent and complete three-dimensional vocabulary (3D)…

Effects of fir sawyer beetle on spatial structure of Siberian fir stands

Treesearch

Vladimir L. Gavrikov; Valentina P. Vetrova

1991-01-01

Insects not only use plants for food and habitat; they also change plant populations by influencing their structure and dynamics. This influence is evidenced in the alteration of the spatial structure of a stand. The fir sawyer, Monochamus urussovi Fisch. (Coleoptera: Cerambycidae), is the most abundant xylophagous insect injuring siberian fir,...

X-ray Tomography and Chemical Imaging within Butterfly Wing Scales

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

Chen Jianhua; Lee Yaochang; Tang, M.-T.

2007-01-19

The rainbow like color of butterfly wings is associated with the internal and surface structures of the wing scales. While the photonic structure of the scales is believed to diffract specific lights at different angle, there is no adequate probe directly answering the 3-D structures with sufficient spatial resolution. The NSRRC nano-transmission x-ray microscope (nTXM) with tens nanometers spatial resolution is able to image biological specimens without artifacts usually introduced in sophisticated sample staining processes. With the intrinsic deep penetration of x-rays, the nTXM is capable of nondestructively investigating the internal structures of fragile and soft samples. In this study,more » we imaged the structure of butterfly wing scales in 3-D view with 60 nm spatial resolution. In addition, synchrotron-radiation-based Fourier transform Infrared (FT-IR) microspectroscopy was employed to analyze the chemical components with spatial information of the butterfly wing scales. Based on the infrared spectral images, we suggest that the major components of scale structure were rich in protein and polysaccharide.« less

The biogeodynamics of microbial landscapes

NASA Astrophysics Data System (ADS)

Battin, T. J.; Hödl, I.; Bertuzzo, E.; Mari, L.; Suweis, S. S.; Rinaldo, A.

2011-12-01

Spatial configuration is fundamental in defining the structural and functional properties of biological systems. Biofilms, surface-attached and matrix-enclosed microorganisms, are a striking example of spatial organisation. Coupled biotic and abiotic processes shape the spatial organisation across scales of the landscapes formed by these benthic biofilms in streams and rivers. Experimenting with such biofilms in streams, we found that, depending on the streambed topography and the related hydrodynamic microenvironment, biofilm landscapes form increasingly diverging spatial patterns as they grow. Strikingly, however, cluster size distributions tend to converge even in contrasting hydrodynamic microenvironments. To reproduce the observed cluster size distributions we used a continuous, size-structured population model. The model accounts for the formation, growth, erosion and merging of biofilm clusters. Our results suggest not only that hydrodynamic forcing induce the diverging patterning of the microbial landscape, but also that microorganisms have developed strategies to equally exploit spatial resources independently of the physical structure of the microenvironment where they live.

The photo-colorimetric space as a medium for the representation of spatial data

NASA Technical Reports Server (NTRS)

Kraiss, K. Friedrich; Widdel, Heino

1989-01-01

Spatial displays and instruments are usually used in the context of vehicle guidance, but it is hard to find applicable spatial formats in information retrieval and interaction systems. Human interaction with spatial data structures and the applicability of the CIE color space to improve dialogue transparency is discussed. A proposal is made to use the color space to code spatially represented data. The semantic distances of the categories of dialogue structures or, more general, of database structures, are determined empirically. Subsequently the distances are transformed and depicted into the color space. The concept is demonstrated for a car diagnosis system, where the category cooling system could, e.g., be coded in blue, the category ignition system in red. Hereby a correspondence between color and semantic distances is achieved. Subcategories can be coded as luminance differences within the color space.

Improvement of axial excitation confinement in temporal focusing-based multiphoton microscopy via spatially modulated illumination

NASA Astrophysics Data System (ADS)

Chang, Chia-Yuan; Chen, Shean-Jen

2017-02-01

Conventional temporal focusing-based multiphoton excitation microscopy (TFMPEM) can offer widefield optical sectioning with an axial excitation confinement (AEC) of a few microns. Herein, a developed TFMPEM with a digital micromirror device (DMD), acting as the blazed grating for light spatial dispersion and simultaneous patterned illumination, has been extended to implement spatially modulated illumination at structured frequency and orientation. By implementing the spatially modulated illumination, the beam coverage at the back-focal aperture of the objective lens can be increased. As a result, the AEC can be condensed from 3.0 μm to 1.5 μm in full width at half maximum for a 2-fold enhancement. Furthermore, by using HiLo microscopy with two structured illuminations at the same spatial frequency but different orientation, biotissue images according to the structured illumination with condensed AEC is obviously superior in contrast and scattering suppression.

Spatial patterns and controls on historical fire regimes and forest structure in the Klamath Mountains

Treesearch

Alan H. Taylor; Carl N. Skinner

2003-01-01

Fire exclusion in mixed conifer forests has increased the risk of fire due to decades of fuel accumulation. Restoration of fire into altered forests is a challenge because of a poor understanding of the spatial and temporal dynamics of fire regimes. In this study the spatial and temporal characteristics of fire regimes and forest age structure are reconstructed in a...

Do You Trust Your Phone?

NASA Astrophysics Data System (ADS)

Castiglione, Aniello; de Prisco, Roberto; de Santis, Alfredo

Despite the promising start, Electronic Commerce has not taken off mostly because of security issues with the communication infrastructures that are popping up threateningly undermining the perceived trustworthiness in Electronic Commerce.

Concerns raised over new EPA members

NASA Astrophysics Data System (ADS)

Gwynne, Peter

2017-12-01

The Trump administration has nominated three new members of the Environmental Protection Agency (EPA) who critics say are undermining laws and “pampering” the industries they are supposed to regulate.

Spatial Distribution of a Large Herbivore Community at Waterholes: An Assessment of Its Stability over Years in Hwange National Park, Zimbabwe.

PubMed

Chamaillé-Jammes, Simon; Charbonnel, Anaïs; Dray, Stéphane; Madzikanda, Hillary; Fritz, Hervé

2016-01-01

The spatial structuring of populations or communities is an important driver of their functioning and their influence on ecosystems. Identifying the (in)stability of the spatial structure of populations is a first step towards understanding the underlying causes of these structures. Here we studied the relative importance of spatial vs. interannual variability in explaining the patterns of abundance of a large herbivore community (8 species) at waterholes in Hwange National Park (Zimbabwe). We analyzed census data collected over 13 years using multivariate methods. Our results showed that variability in the census data was mostly explained by the spatial structure of the community, as some waterholes had consistently greater herbivore abundance than others. Some temporal variability probably linked to Park-scale migration dependent on annual rainfall was noticeable, however. Once this was accounted for, little temporal variability remained to be explained, suggesting that other factors affecting herbivore abundance over time had a negligible effect at the scale of the study. The extent of spatial and temporal variability in census data was also measured for each species. This study could help in projecting the consequences of surface water management, and more generally presents a methodological framework to simultaneously address the relative importance of spatial vs. temporal effects in driving the distribution of organisms across landscapes.

Spatial Distribution of a Large Herbivore Community at Waterholes: An Assessment of Its Stability over Years in Hwange National Park, Zimbabwe

PubMed Central

Chamaillé-Jammes, Simon; Charbonnel, Anaïs; Dray, Stéphane; Madzikanda, Hillary; Fritz, Hervé

2016-01-01

The spatial structuring of populations or communities is an important driver of their functioning and their influence on ecosystems. Identifying the (in)stability of the spatial structure of populations is a first step towards understanding the underlying causes of these structures. Here we studied the relative importance of spatial vs. interannual variability in explaining the patterns of abundance of a large herbivore community (8 species) at waterholes in Hwange National Park (Zimbabwe). We analyzed census data collected over 13 years using multivariate methods. Our results showed that variability in the census data was mostly explained by the spatial structure of the community, as some waterholes had consistently greater herbivore abundance than others. Some temporal variability probably linked to Park-scale migration dependent on annual rainfall was noticeable, however. Once this was accounted for, little temporal variability remained to be explained, suggesting that other factors affecting herbivore abundance over time had a negligible effect at the scale of the study. The extent of spatial and temporal variability in census data was also measured for each species. This study could help in projecting the consequences of surface water management, and more generally presents a methodological framework to simultaneously address the relative importance of spatial vs. temporal effects in driving the distribution of organisms across landscapes. PMID:27074044

The inclusive fitness controversy: finding a way forward.

PubMed

Birch, Jonathan

2017-07-01

This paper attempts to reconcile critics and defenders of inclusive fitness by constructing a synthesis that does justice to the insights of both. I argue that criticisms of the regression-based version of Hamilton's rule, although they undermine its use for predictive purposes, do not undermine its use as an organizing framework for social evolution research. I argue that the assumptions underlying the concept of inclusive fitness, conceived as a causal property of an individual organism, are unlikely to be exactly true in real populations, but they are approximately true given a specific type of weak selection that Hamilton took, on independent grounds, to be responsible for the cumulative assembly of complex adaptation. Finally, I reflect on the uses and limitations of 'design thinking' in social evolution research.

High temperature and temperature variation undermine future disease susceptibility in a population of the invasive garden ant Lasius neglectus.

PubMed

Pamminger, Tobias; Steier, Thomas; Tragust, Simon

2016-06-01

Environmental temperature and temperature variation can have strong effects on the outcome of host-parasite interactions. Whilst such effects have been reported for different host systems, long-term consequences of pre-infection temperatures on host susceptibility and immunity remain understudied. Here, we show that experiencing both a biologically relevant increase in temperature and temperature variation undermines future disease susceptibility of the invasive garden ant Lasius neglectus when challenged with a pathogen under a constant temperature regime. In light of the economic and ecological importance of many social insects, our results emphasise the necessity to take the hosts' temperature history into account when studying host-parasite interactions under both natural and laboratory conditions, especially in the face of global change.

The inclusive fitness controversy: finding a way forward

PubMed Central

2017-01-01

This paper attempts to reconcile critics and defenders of inclusive fitness by constructing a synthesis that does justice to the insights of both. I argue that criticisms of the regression-based version of Hamilton's rule, although they undermine its use for predictive purposes, do not undermine its use as an organizing framework for social evolution research. I argue that the assumptions underlying the concept of inclusive fitness, conceived as a causal property of an individual organism, are unlikely to be exactly true in real populations, but they are approximately true given a specific type of weak selection that Hamilton took, on independent grounds, to be responsible for the cumulative assembly of complex adaptation. Finally, I reflect on the uses and limitations of ‘design thinking’ in social evolution research. PMID:28791162

High temperature and temperature variation undermine future disease susceptibility in a population of the invasive garden ant Lasius neglectus

NASA Astrophysics Data System (ADS)

Pamminger, Tobias; Steier, Thomas; Tragust, Simon

2016-06-01

Environmental temperature and temperature variation can have strong effects on the outcome of host-parasite interactions. Whilst such effects have been reported for different host systems, long-term consequences of pre-infection temperatures on host susceptibility and immunity remain understudied. Here, we show that experiencing both a biologically relevant increase in temperature and temperature variation undermines future disease susceptibility of the invasive garden ant Lasius neglectus when challenged with a pathogen under a constant temperature regime. In light of the economic and ecological importance of many social insects, our results emphasise the necessity to take the hosts' temperature history into account when studying host-parasite interactions under both natural and laboratory conditions, especially in the face of global change.

Attempts to Undermine Tobacco Control

PubMed Central

Sebrié, Ernesto M.; Glantz, Stanton A.

2007-01-01

We sought to understand how the tobacco industry uses “youth smoking prevention” programs in Latin America. We analyzed tobacco industry documents, so-called “social reports,” media reports, and material provided by Latin American public health advocates. Since the early 1990s, multinational tobacco companies have promoted “youth smoking prevention” programs as part of their “Corporate Social Responsibility” campaigns. The companies also partnered with third-party allies in Latin America, most notably nonprofit educational organizations and education and health ministries. Even though there is no evidence that these programs reduce smoking among youths, they have met the industry’s goal of portraying the companies as concerned corporate citizens and undermining effective tobacco control interventions that are required by the World Health Organization Framework Convention on Tobacco Control. PMID:17600260

High performances of dual network PVA hydrogel modified by PVP using borax as the structure-forming accelerator

PubMed Central

Huang, Min; Hou, Yi; Li, Yubao; Wang, Danqing; Zhang, Li

2017-01-01

Abstract A dual network hydrogel made up of polyvinylalcohol (PVA) crosslinked by borax and polyvinylpyrrolidone (PVP) was prepared by means of freezing-thawing circles. Here PVP was incorporated by linking with PVA to form a network structure, while the introduction of borax played the role of crosslinking PVA chains to accelerate the formation of a dual network structure in PVA/PVP composite hydrogel, thus endowing the hydrogel with high mechanical properties. The effects of both PVP and borax on the hydrogels were evaluated by comparing the two systems of PVA/PVP/borax and PVA/borax hydrogels. In the former system, adding 4.0% PVP not only increased the water content and the storage modulus but also enhanced the mechanical strength of the final hydrogel. But an overdose of PVP just as more than 4.0% tended to undermine the structure of hydrogels, and thus deteriorated hydrogels’ properties because of the weakened secondary interaction between PVP and PVA. Likewise, increasing borax could promote the gel crosslinking degree, thus making gels show a decrease in water content and swelling ratio, meanwhile shrinking the pores inside the hydrogels and finally enhancing the mechanical strength of hydrogels prominently. The developed hydrogel with high performances holds great potential for applications in biomedical and industrial fields. PMID:29491822

Binder-free graphene foams for O2 electrodes of Li-O2 batteries.

PubMed

Zhang, Wenyu; Zhu, Jixin; Ang, Huixiang; Zeng, Yi; Xiao, Ni; Gao, Yiben; Liu, Weiling; Hng, Huey Hoon; Yan, Qingyu

2013-10-21

We report a novel method to prepare bind-free graphene foams as O2 electrodes for Li-O2 batteries. The graphene foams are synthesized by electrochemical leavening of the graphite papers, followed by annealing in inert gas to control the amount of structural defects in the graphene foams. It was found that the structural defects were detrimental to the processes of the ORR and OER in Li-O2 batteries. The round-trip efficiencies and the cycling stabilities of the graphene foams were undermined by the structural defects. For example, the as-prepared graphene foam with a high defect level (ID/IG = 0.71) depicted a round-trip efficiency of only 0.51 and a 20(th)-cycle discharge capacity of only 340 mA h g(-1) at a current density of 100 mA g(-1). By contrast, the graphene foam electrode annealed at 800 °C with ID/IG = 0.07 delivered a round-trip efficiency of up to 80% with a stable discharge voltage at ~2.8 V and a stable charge voltage below 3.8 V for 20 cycles. According to the analysis on the electrodes after 20 cycles, the structural defects led to the quickened decay of the graphene foams and boosted the formation of side products.

Contrasting patterns of fine-scale herb layer species composition in temperate forests

NASA Astrophysics Data System (ADS)

Chudomelová, Markéta; Zelený, David; Li, Ching-Feng

2017-04-01

Although being well described at the landscape level, patterns in species composition of forest herb layer are rarely studied at smaller scales. Here, we examined fine-scale environmental determinants and spatial structures of herb layer communities in thermophilous oak- and hornbeam dominated forests of the south-eastern part of the Czech Republic. Species composition of herb layer vegetation and environmental variables were recorded within a fixed grid of 2 × 2 m subplots regularly distributed within 1-ha quadrate plots in three forest stands. For each site, environmental models best explaining species composition were constructed using constrained ordination analysis. Spatial eigenvector mapping was used to model and account for spatial structures in community variation. Mean Ellenberg indicator values calculated for each subplot were used for ecological interpretation of spatially structured residual variation. The amount of variation explained by environmental and spatial models as well as the selection of variables with the best explanatory power differed among sites. As an important environmental factor, relative elevation was common to all three sites, while pH and canopy openness were shared by two sites. Both environmental and community variation was mostly coarse-scaled, as was the spatially structured portion of residual variation. When corrected for bias due to spatial autocorrelation, those environmental factors with already weak explanatory power lost their significance. Only a weak evidence of possibly omitted environmental predictor was found for autocorrelated residuals of site models using mean Ellenberg indicator values. Community structure was determined by different factors at different sites. The relative importance of environmental filtering vs. spatial processes was also site specific, implying that results of fine-scale studies tend to be shaped by local conditions. Contrary to expectations based on other studies, overall dominance of spatial processes at fine scale has not been detected. Ecologists should keep this in mind when making generalizations about community dynamics.

Bioinformatic pipelines in Python with Leaf

PubMed Central

2013-01-01

Background An incremental, loosely planned development approach is often used in bioinformatic studies when dealing with custom data analysis in a rapidly changing environment. Unfortunately, the lack of a rigorous software structuring can undermine the maintainability, communicability and replicability of the process. To ameliorate this problem we propose the Leaf system, the aim of which is to seamlessly introduce the pipeline formality on top of a dynamical development process with minimum overhead for the programmer, thus providing a simple layer of software structuring. Results Leaf includes a formal language for the definition of pipelines with code that can be transparently inserted into the user’s Python code. Its syntax is designed to visually highlight dependencies in the pipeline structure it defines. While encouraging the developer to think in terms of bioinformatic pipelines, Leaf supports a number of automated features including data and session persistence, consistency checks between steps of the analysis, processing optimization and publication of the analytic protocol in the form of a hypertext. Conclusions Leaf offers a powerful balance between plan-driven and change-driven development environments in the design, management and communication of bioinformatic pipelines. Its unique features make it a valuable alternative to other related tools. PMID:23786315

Wettability modification of porous PET by atmospheric femtosecond PLD

NASA Astrophysics Data System (ADS)

Assaf, Youssef; Forstmann, Guillaume; Kietzig, Anne-Marie

2018-04-01

In this study, porous structures were created on poly(ethylene terephthalate) (PET) by femtosecond (fs) laser micromachining. While such structures offer a texture that is desirable for several applications, their wettability does not always match the application in question. The aim of this investigation is to tune the wettability of such surfaces by incorporating a controlled amount of nanoparticles into the structure. The machined PET samples were thus used as substrates for fs pulsed laser deposition (PLD) of titanium under ambient conditions. The nanoparticles were deposited as nanochain clusters due to the formation of an oxide layer between individual nanoparticles. The stability of nanoparticle incorporation was tested by placing the samples in an ultrasonic ethanol bath. Results indicated that nanoparticles were still successfully incorporated into the microstructure after sonication. Nanoparticle surface coverage was observed to be controllable through the operating fluence. The dynamic contact angles of the resulting composite surface were observed to decrease with increasing titanium incorporation. Therefore, this work highlights atmospheric fs PLD as a method for wettability modification of high surface area microstructures without undermining their topology. In addition, this technique uses almost the same equipment as the machining process by which the microstructures are initially created, further highlighting its practicality.

Structure and information in spatial segregation

PubMed Central

2017-01-01

Ethnoracial residential segregation is a complex, multiscalar phenomenon with immense moral and economic costs. Modeling the structure and dynamics of segregation is a pressing problem for sociology and urban planning, but existing methods have limitations. In this paper, we develop a suite of methods, grounded in information theory, for studying the spatial structure of segregation. We first advance existing profile and decomposition methods by posing two related regionalization methods, which allow for profile curves with nonconstant spatial scale and decomposition analysis with nonarbitrary areal units. We then formulate a measure of local spatial scale, which may be used for both detailed, within-city analysis and intercity comparisons. These methods highlight detailed insights in the structure and dynamics of urban segregation that would be otherwise easy to miss or difficult to quantify. They are computationally efficient, applicable to a broad range of study questions, and freely available in open source software. PMID:29078323

Structure and information in spatial segregation.

PubMed

Chodrow, Philip S

2017-10-31

Ethnoracial residential segregation is a complex, multiscalar phenomenon with immense moral and economic costs. Modeling the structure and dynamics of segregation is a pressing problem for sociology and urban planning, but existing methods have limitations. In this paper, we develop a suite of methods, grounded in information theory, for studying the spatial structure of segregation. We first advance existing profile and decomposition methods by posing two related regionalization methods, which allow for profile curves with nonconstant spatial scale and decomposition analysis with nonarbitrary areal units. We then formulate a measure of local spatial scale, which may be used for both detailed, within-city analysis and intercity comparisons. These methods highlight detailed insights in the structure and dynamics of urban segregation that would be otherwise easy to miss or difficult to quantify. They are computationally efficient, applicable to a broad range of study questions, and freely available in open source software. Published under the PNAS license.

Estimating clandestine activities from partially observed processes: illegal transhipment of fish catches among vessels

NASA Astrophysics Data System (ADS)

Wilcox, C.; Ford, J.

2016-12-01

Crimes involving fishers impose significant costs on fisheries, managers and national governments. These crimes also lead to unsustainable harvesting practices, as they undermine both knowledge of the status of fisheries stocks and limits on their harvesting. One of the greatest contributors to fisheries crimes globally is transfer of fish catch among vessels, otherwise known as transshipment. While legal transshipment provides economic advantages to vessels by increasing their efficiency, illegal transshipment can allow them to avoid regulations, catch prohibited species, and fish with impunity in prohibited locations such as waters of foreign countries. Despite the presence of a number of monitoring technologies for tracking fishing vessels, transshipment is frequently done clandestinely. Here we present a statistical model for transshipment in a Southeast Asian tuna fishery. We utilize both spatial and temporal information on vessel movement patterns in a statistical model to infer unobserved transshipment events among vessels. We provide a risk analysis framework for forecasting likely transshipment events, based on our analysis of vessel movement patterns. The tools we present are widely applicable to a variety of fisheries and types of tracking data, allowing managers to more effectively screen the large volume of data tracking systems create and quickly identify suspicious behavior.

Sensitivity to Relational Similarity and Object Similarity in Apes and Children.

PubMed

Christie, Stella; Gentner, Dedre; Call, Josep; Haun, Daniel Benjamin Moritz

2016-02-22

Relational reasoning is a hallmark of sophisticated cognition in humans. Does it exist in other primates? Despite some affirmative answers, there appears to be a wide gap in relational ability between humans and other primates--even other apes. Here, we test one possible explanation for this gap, motivated by developmental research showing that young humans often fail at relational reasoning tasks because they focus on objects instead of relations. When asked, "duck:duckling is like tiger:?," preschool children choose another duckling (object match) rather than a cub. If other apes share this focus on concrete objects, it could undermine their relational reasoning in similar ways. To test this, we compared great apes and 3-year-old humans' relational reasoning on the same spatial mapping task, with and without competing object matches. Without competing object matches, both children and Pan species (chimpanzees and bonobos) spontaneously used relational similarity, albeit children more so. But when object matches were present, only children responded strongly to them. We conclude that the relational gap is not due to great apes' preference for concrete objects. In fact, young humans show greater object focus than nonhuman apes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Decoding-Accuracy-Based Sequential Dimensionality Reduction of Spatio-Temporal Neural Activities

NASA Astrophysics Data System (ADS)

Funamizu, Akihiro; Kanzaki, Ryohei; Takahashi, Hirokazu

Performance of a brain machine interface (BMI) critically depends on selection of input data because information embedded in the neural activities is highly redundant. In addition, properly selected input data with a reduced dimension leads to improvement of decoding generalization ability and decrease of computational efforts, both of which are significant advantages for the clinical applications. In the present paper, we propose an algorithm of sequential dimensionality reduction (SDR) that effectively extracts motor/sensory related spatio-temporal neural activities. The algorithm gradually reduces input data dimension by dropping neural data spatio-temporally so as not to undermine the decoding accuracy as far as possible. Support vector machine (SVM) was used as the decoder, and tone-induced neural activities in rat auditory cortices were decoded into the test tone frequencies. SDR reduced the input data dimension to a quarter and significantly improved the accuracy of decoding of novel data. Moreover, spatio-temporal neural activity patterns selected by SDR resulted in significantly higher accuracy than high spike rate patterns or conventionally used spatial patterns. These results suggest that the proposed algorithm can improve the generalization ability and decrease the computational effort of decoding.

A Climatic Stability Approach to Prioritizing Global Conservation Investments

PubMed Central

Iwamura, Takuya; Wilson, Kerrie A.; Venter, Oscar; Possingham, Hugh P.

2010-01-01

Climate change is impacting species and ecosystems globally. Many existing templates to identify the most important areas to conserve terrestrial biodiversity at the global scale neglect the future impacts of climate change. Unstable climatic conditions are predicted to undermine conservation investments in the future. This paper presents an approach to developing a resource allocation algorithm for conservation investment that incorporates the ecological stability of ecoregions under climate change. We discover that allocating funds in this way changes the optimal schedule of global investments both spatially and temporally. This allocation reduces the biodiversity loss of terrestrial endemic species from protected areas due to climate change by 22% for the period of 2002–2052, when compared to allocations that do not consider climate change. To maximize the resilience of global biodiversity to climate change we recommend that funding be increased in ecoregions located in the tropics and/or mid-elevation habitats, where climatic conditions are predicted to remain relatively stable. Accounting for the ecological stability of ecoregions provides a realistic approach to incorporating climate change into global conservation planning, with potential to save more species from extinction in the long term. PMID:21152095

Managing the evolution of herbicide resistance.

PubMed

Evans, Jeffrey A; Tranel, Patrick J; Hager, Aaron G; Schutte, Brian; Wu, Chenxi; Chatham, Laura A; Davis, Adam S

2016-01-01

Understanding and managing the evolutionary responses of pests and pathogens to control efforts is essential to human health and survival. Herbicide-resistant (HR) weeds undermine agricultural sustainability, productivity and profitability, yet the epidemiology of resistance evolution - particularly at landscape scales - is poorly understood. We studied glyphosate resistance in a major agricultural weed, Amaranthus tuberculatus (common waterhemp), using landscape, weed and management data from 105 central Illinois grain farms, including over 500 site-years of herbicide application records. Glyphosate-resistant (GR) A. tuberculatus occurrence was greatest in fields with frequent glyphosate applications, high annual rates of herbicide mechanism of action (MOA) turnover and few MOAs field(-1) year(-1) . Combining herbicide MOAs at the time of application by herbicide mixing reduced the likelihood of GR A. tuberculatus. These findings illustrate the importance of examining large-scale evolutionary processes at relevant spatial scales. Although measures such as herbicide mixing may delay GR or other HR weed traits, they are unlikely to prevent them. Long-term weed management will require truly diversified management practices that minimize selection for herbicide resistance traits. © 2015 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Applying Thiessen Polygon Catchment Areas and Gridded Population Weights to Estimate Conflict-Driven Population Changes in South Sudan

NASA Astrophysics Data System (ADS)

Jordan, L.

2017-10-01

Recent violence in South Sudan produced significant levels of conflict-driven migration undermining the accuracy and utility of both national and local level population forecasts commonly used in demographic estimates, public health metrics and food security proxies. This article explores the use of Thiessen Polygons and population grids (Gridded Population of the World, WorldPop and LandScan) as weights for estimating the catchment areas for settlement locations that serve large populations of internally displaced persons (IDP), in order to estimate the county-level in- and out-migration attributable to conflict-driven displacement between 2014-2015. Acknowledging IDP totals improves internal population estimates presented by global population databases. Unlike other forecasts, which produce spatially uniform increases in population, accounting for displaced population reveals that 15 percent of counties (n = 12) increased in population over 20 percent, and 30 percent of counties (n = 24) experienced zero or declining population growth, due to internal displacement and refugee out-migration. Adopting Thiessen Polygon catchment zones for internal migration estimation can be applied to other areas with United Nations IDP settlement data, such as Yemen, Somalia, and Nigeria.

Magnetic resonance spectroscopic imaging at superresolution: Overview and perspectives.

PubMed

Kasten, Jeffrey; Klauser, Antoine; Lazeyras, François; Van De Ville, Dimitri

2016-02-01

The notion of non-invasive, high-resolution spatial mapping of metabolite concentrations has long enticed the medical community. While magnetic resonance spectroscopic imaging (MRSI) is capable of achieving the requisite spatio-spectral localization, it has traditionally been encumbered by significant resolution constraints that have thus far undermined its clinical utility. To surpass these obstacles, research efforts have primarily focused on hardware enhancements or the development of accelerated acquisition strategies to improve the experimental sensitivity per unit time. Concomitantly, a number of innovative reconstruction techniques have emerged as alternatives to the standard inverse discrete Fourier transform (DFT). While perhaps lesser known, these latter methods strive to effect commensurate resolution gains by exploiting known properties of the underlying MRSI signal in concert with advanced image and signal processing techniques. This review article aims to aggregate and provide an overview of the past few decades of so-called "superresolution" MRSI reconstruction methodologies, and to introduce readers to current state-of-the-art approaches. A number of perspectives are then offered as to the future of high-resolution MRSI, with a particular focus on translation into clinical settings. Copyright © 2015 Elsevier Inc. All rights reserved.

Deficits in oculomotor performance in pediatric epilepsy

PubMed Central

Asato, Miya R.; Nawarawong, Natalie; Hermann, Bruce; Crumrine, Patricia; Luna, Beatriz

2010-01-01

Summary Purpose Given evidence of limitations in neuropsychological performance in epilepsy, we probed the integrity of components of cognition, including speed of processing, response inhibition, and spatial working memory supporting executive function in pediatric epilepsy patients and matched controls. Methods A total of 44 pairs of controls and medically treated pediatric epilepsy patients with no known brain pathology completed cognitive oculomotor tasks, computerized neuropsychological testing, and psychiatric assessment. Results Patients showed slower reaction time to initiate a saccadic response compared to controls but had intact saccade accuracy. Cognitively driven responses including response inhibition were impaired in the patient group. Patients had increased incidence of comorbid psychopathology but comorbidity did not predict worse functioning compared to patients with no ADHD. Epilepsy type and medication status were not predictive of outcome. More complex neuropsychological performance was impaired in tasks requiring visual memory and sequential processing which was correlated with inhibitory control and antisaccade accuracy. Discussion Pediatric epilepsy may be associated with vulnerabilities that specifically undermine speed of processing and response inhibition but not working memory and may underlie known neuropsychological performance limitations. This particular profile of abnormalities may be associated with seizure-mediated compromises in brain maturation early in development. PMID:21087246

Spatial structure increases the waiting time for cancer

PubMed Central

Martens, Erik A.; Kostadinov, Rumen; Maley, Carlo C.; Hallatschek, Oskar

2012-01-01

Cancer results from a sequence of genetic and epigenetic changes which lead to a variety of abnormal phenotypes including increased proliferation and survival of somatic cells, and thus, to a selective advantage of pre-cancerous cells. The notion of cancer progression as an evolutionary process has been experiencing increasing interest in recent years. Many efforts have been made to better understand and predict the progression to cancer using mathematical models; these mostly consider the evolution of a well-mixed cell population, even though pre-cancerous cells often evolve in highly structured epithelial tissues. In this study, we propose a novel model of cancer progression that considers a spatially structured cell population where clones expand via adaptive waves. This model is used to assess two different paradigms of asexual evolution that have been suggested to delineate the process of cancer progression. The standard scenario of periodic selection assumes that driver mutations are accumulated strictly sequentially over time. However, when the mutation supply is sufficiently high, clones may arise simultaneously on distinct genetic backgrounds, and clonal adaptation waves interfere with each other. We find that in the presence of clonal interference, spatial structure increases the waiting time for cancer, leads to a patchwork structure of non-uniformly sized clones, decreases the survival probability of virtually neutral (passenger) mutations, and that genetic distance begins to increase over a characteristic length scale Lc. These characteristic features of clonal interference may help to predict the onset of cancers with pronounced spatial structure and to interpret spatially-sampled genetic data obtained from biopsies. Our estimates suggest that clonal interference likely occurs in the progression of colon cancer, and possibly other cancers where spatial structure matters. PMID:22707911

Spatial structure increases the waiting time for cancer

NASA Astrophysics Data System (ADS)

Martens, Erik A.; Kostadinov, Rumen; Maley, Carlo C.; Hallatschek, Oskar

2011-11-01

Cancer results from a sequence of genetic and epigenetic changes that lead to a variety of abnormal phenotypes including increased proliferation and survival of somatic cells and thus to a selective advantage of pre-cancerous cells. The notion of cancer progression as an evolutionary process has been attracting increasing interest in recent years. A great deal of effort has been made to better understand and predict the progression to cancer using mathematical models; these mostly consider the evolution of a well-mixed cell population, even though pre-cancerous cells often evolve in highly structured epithelial tissues. In this study, we propose a novel model of cancer progression that considers a spatially structured cell population where clones expand via adaptive waves. This model is used to assess two different paradigms of asexual evolution that have been suggested to delineate the process of cancer progression. The standard scenario of periodic selection assumes that driver mutations are accumulated strictly sequentially over time. However, when the mutation supply is sufficiently high, clones may arise simultaneously on distinct genetic backgrounds, and clonal adaptation waves interfere with each other. We find that in the presence of clonal interference, spatial structure increases the waiting time for cancer, leads to a patchwork structure of non-uniformly sized clones and decreases the survival probability of virtually neutral (passenger) mutations, and that genetic distance begins to increase over a characteristic length scale Lc. These characteristic features of clonal interference may help us to predict the onset of cancers with pronounced spatial structure and to interpret spatially sampled genetic data obtained from biopsies. Our estimates suggest that clonal interference likely occurs in the progression of colon cancer and possibly other cancers where spatial structure matters.

Three dimensional simulation of spatial and temporal variability of stratospheric hydrogen chloride

NASA Technical Reports Server (NTRS)

Kaye, Jack A.; Rood, Richard B.; Jackman, Charles H.; Allen, Dale J.; Larson, Edmund M.

1989-01-01

Spatial and temporal variability of atmospheric HCl columns are calculated for January 1979 using a three-dimensional chemistry-transport model designed to provide the best possible representation of stratospheric transport. Large spatial and temporal variability of the HCl columns is shown to be correlated with lower stratospheric potential vorticity and thus to be of dynamical origin. Systematic longitudinal structure is correlated with planetary wave structure. These results can help place spatially and temporally isolated column and profile measurements in a regional and/or global perspective.

Design and realization of tourism spatial decision support system based on GIS

NASA Astrophysics Data System (ADS)

Ma, Zhangbao; Qi, Qingwen; Xu, Li

2008-10-01

In this paper, the existing problems of current tourism management information system are analyzed. GIS, tourism as well as spatial decision support system are introduced, and the application of geographic information system technology and spatial decision support system to tourism management and the establishment of tourism spatial decision support system based on GIS are proposed. System total structure, system hardware and software environment, database design and structure module design of this system are introduced. Finally, realization methods of this systemic core functions are elaborated.

Factor structure of the Spanish version of the Object-Spatial Imagery and Verbal Questionnaire.

PubMed

Campos, Alfredo; Pérez-Fabello, María José

2011-04-01

The reliability and factor structure of the Spanish version of the Object-Spatial Imagery and Verbal Questionnaire (OSIVQ) were assessed in a sample of 213 Spanish university graduates. The questionnaire measures three types of processing preferences (verbal, object imagery, and spatial imagery). Principal components analysis with varimax rotation identified three factors, corresponding to the three scales proposed in the original version, explaining 33.1% of the overall variance. Cronbach's alphas were .72, .77, and .81 for the verbal, object imagery, and spatial imagery scales, respectively.

The use of traditional medicine by Ghanaians in Canada.

PubMed

Barimah, Kofi B; van Teijlingen, Edwin R

2008-06-16

Research into health and health-care seeking behaviour amongst immigrant populations suggests that culturally-based behaviours change over time towards those prevalent in the host culture. Such acculturation of immigrant groups occurs as part of the interaction of immigrants with mainstream culture. This study examined the acculturation of Ghanaian immigrants in Greater Toronto Area (Canada) focusing particularly on attitudes towards and usage of Ghanaian traditional medicine (TRM). The study used both quantitative and qualitative methods. Structured questionnaire interviews were conducted with a sample of Ghanaians in active collaboration with the Ghanaian-Canadian Association in the Greater Toronto Area (GTA). A total of 512 questionnaire interviews were conducted. In addition, three focus groups of nine participants each were conducted with a sub-sample of Ghanaians in Canada. Both the questionnaire and the focus groups indicated that nearly 73% of the Ghanaian immigrants in Canada have a positive attitude toward Ghanaian TRM. This is in comparison with less than 30% who have changed their attitude for various reasons. Some of the attraction of TRM lies in its holistic origin. Ghanaians in the GTA have been pursuing 'integration' and 'assimilation' in their acculturation in Canada. Some have given up or modified some of their attitudes and opinions toward TRM to embrace the 'modern' or 'civilized' way of living. There is the need for health care providers and other stakeholders to be aware of the influence of religion on African immigrants during their acculturation process. Although modernity is said to be founded on the 'ruthless undermining of tradition', there is no evidence to suggest that Ghanaian traditional religion has been undermined to such an extent that there is a major change in attitudes towards TRM.

Pig producer perspectives on the use of meat inspection as an animal health and welfare diagnostic tool in the Republic of Ireland and Northern Ireland.

PubMed

Devitt, Catherine; Boyle, Laura; Teixeira, D L; O'Connell, N E; Hawe, M; Hanlon, Alison

2015-01-01

Currently, there is growing interest in developing ante and post mortem meat inspection (MI) to incorporate measures of pig health and welfare for use as a diagnostic tool on pig farms. However, the success of the development of the MI process requires stakeholder engagement with the process. Knowledge gaps and issues of trust can undermine the effective exchange and utilisation of information across the supply chain. A social science research methodology was employed to establish stakeholder perspectives towards the development of MI to include measures of pig health and welfare. In this paper the findings of semi-structured telephone interviews with 18 pig producers from the Republic of Ireland and Northern Ireland are presented. Producers recognised the benefit of the utilisation of MI data as a health and welfare diagnostic tool. This acknowledgment, however, was undermined for some by dissatisfaction with the current system of MI information feedback, by trust and fairness concerns, and by concerns regarding the extent to which data would be used in the producers' interests. Tolerance of certain animal welfare issues may also have a negative impact on how producers viewed the potential of MI data. The private veterinary practitioner was viewed as playing a vital role in assisting them with the interpretation of MI data for herd health planning. The development of positive relationships based on trust, commitment and satisfaction across the supply chain may help build a positive environment for the effective utilisation of MI data in improving pig health and welfare. The utilisation of MI as a diagnostic tool would benefit from the development of a communication strategy aimed at building positive relationships between stakeholders in the pig industry.

The importance of spatial ability and mental models in learning anatomy

NASA Astrophysics Data System (ADS)

Chatterjee, Allison K.

As a foundational course in medical education, gross anatomy serves to orient medical and veterinary students to the complex three-dimensional nature of the structures within the body. Understanding such spatial relationships is both fundamental and crucial for achievement in gross anatomy courses, and is essential for success as a practicing professional. Many things contribute to learning spatial relationships; this project focuses on a few key elements: (1) the type of multimedia resources, particularly computer-aided instructional (CAI) resources, medical students used to study and learn; (2) the influence of spatial ability on medical and veterinary students' gross anatomy grades and their mental models; and (3) how medical and veterinary students think about anatomy and describe the features of their mental models to represent what they know about anatomical structures. The use of computer-aided instruction (CAI) by gross anatomy students at Indiana University School of Medicine (IUSM) was assessed through a questionnaire distributed to the regional centers of the IUSM. Students reported using internet browsing, PowerPoint presentation software, and email on a daily bases to study gross anatomy. This study reveals that first-year medical students at the IUSM make limited use of CAI to study gross anatomy. Such studies emphasize the importance of examining students' use of CAI to study gross anatomy prior to development and integration of electronic media into the curriculum and they may be important in future decisions regarding the development of alternative learning resources. In order to determine how students think about anatomical relationships and describe the features of their mental models, personal interviews were conducted with select students based on students' ROT scores. Five typologies of the characteristics of students' mental models were identified and described: spatial thinking, kinesthetic approach, identification of anatomical structures, problem solving strategies, and study methods. Students with different levels of spatial ability visualize and think about anatomy in qualitatively different ways, which is reflected by the features of their mental models. Low spatial ability students thought about and used two-dimensional images from the textbook. They possessed basic two-dimensional models of anatomical structures; they placed emphasis on diagrams and drawings in their studies; and they re-read anatomical problems many times before answering. High spatial ability students thought fully in three-dimensional and imagined rotation and movement of the structures; they made use of many types of images and text as they studied and solved problems. They possessed elaborate three-dimensional models of anatomical structures which they were able to manipulate to solve problems; and they integrated diagrams, drawings, and written text in their studies. Middle spatial ability students were a mix between both low and high spatial ability students. They imagined two-dimensional images popping out of the flat paper to become more three-dimensional, but still relied on drawings and diagrams. Additionally, high spatial ability students used a higher proportion of anatomical terminology than low spatial ability or middle spatial ability students. This provides additional support to the premise that high spatial students' mental models are a complex mixture of imagistic representations and propositional representations that incorporate correct anatomical terminology. Low spatial ability students focused on the function of structures and ways to group information primarily for the purpose of recall. This supports the theory that low spatial students' mental models will be characterized by more on imagistic representations that are general in nature. (Abstract shortened by UMI.)

Relationship Study on Land Use Spatial Distribution Structure and Energy-Related Carbon Emission Intensity in Different Land Use Types of Guangdong, China, 1996–2008

PubMed Central

Huang, Yi; Yang, Lei

2013-01-01

This study attempts to discuss the relationship between land use spatial distribution structure and energy-related carbon emission intensity in Guangdong during 1996–2008. We quantized the spatial distribution structure of five land use types including agricultural land, industrial land, residential and commercial land, traffic land, and other land through applying spatial Lorenz curve and Gini coefficient. Then the corresponding energy-related carbon emissions in each type of land were calculated in the study period. Through building the reasonable regression models, we found that the concentration degree of industrial land is negatively correlated with carbon emission intensity in the long term, whereas the concentration degree is positively correlated with carbon emission intensity in agricultural land, residential and commercial land, traffic land, and other land. The results also indicate that land use spatial distribution structure affects carbon emission intensity more intensively than energy efficiency and production efficiency do. These conclusions provide valuable reference to develop comprehensive policies for energy conservation and carbon emission reduction in a new perspective. PMID:23476128

Spatial Structures of the Environment and of Dispersal Impact Species Distribution in Competitive Metacommunities

PubMed Central

Ai, Dexiecuo; Gravel, Dominique; Chu, Chengjin; Wang, Gang

2013-01-01

The correspondence between species distribution and the environment depends on species’ ability to track favorable environmental conditions (via dispersal) and to maintain competitive hierarchy against the constant influx of migrants (mass effect) and demographic stochasticity (ecological drift). Here we report a simulation study of the influence of landscape structure on species distribution. We consider lottery competition for space in a spatially heterogeneous environment, where the landscape is represented as a network of localities connected by dispersal. We quantified the contribution of neutrality and species sorting to their spatial distribution. We found that neutrality increases and the strength of species-sorting decreases with the centrality of a community in the landscape when the average dispersal among communities is low, whereas the opposite was found at elevated dispersal. We also found that the strength of species-sorting increases with environmental heterogeneity. Our results illustrate that spatial structure of the environment and of dispersal must be taken into account for understanding species distribution. We stress the importance of spatial geographic structure on the relative importance of niche vs. neutral processes in controlling community dynamics. PMID:23874815

Spatial structures of the environment and of dispersal impact species distribution in competitive metacommunities.

PubMed

Ai, Dexiecuo; Gravel, Dominique; Chu, Chengjin; Wang, Gang

2013-01-01

The correspondence between species distribution and the environment depends on species' ability to track favorable environmental conditions (via dispersal) and to maintain competitive hierarchy against the constant influx of migrants (mass effect) and demographic stochasticity (ecological drift). Here we report a simulation study of the influence of landscape structure on species distribution. We consider lottery competition for space in a spatially heterogeneous environment, where the landscape is represented as a network of localities connected by dispersal. We quantified the contribution of neutrality and species sorting to their spatial distribution. We found that neutrality increases and the strength of species-sorting decreases with the centrality of a community in the landscape when the average dispersal among communities is low, whereas the opposite was found at elevated dispersal. We also found that the strength of species-sorting increases with environmental heterogeneity. Our results illustrate that spatial structure of the environment and of dispersal must be taken into account for understanding species distribution. We stress the importance of spatial geographic structure on the relative importance of niche vs. neutral processes in controlling community dynamics.

Relationship study on land use spatial distribution structure and energy-related carbon emission intensity in different land use types of Guangdong, China, 1996-2008.

PubMed

Huang, Yi; Xia, Bin; Yang, Lei

2013-01-01

This study attempts to discuss the relationship between land use spatial distribution structure and energy-related carbon emission intensity in Guangdong during 1996-2008. We quantized the spatial distribution structure of five land use types including agricultural land, industrial land, residential and commercial land, traffic land, and other land through applying spatial Lorenz curve and Gini coefficient. Then the corresponding energy-related carbon emissions in each type of land were calculated in the study period. Through building the reasonable regression models, we found that the concentration degree of industrial land is negatively correlated with carbon emission intensity in the long term, whereas the concentration degree is positively correlated with carbon emission intensity in agricultural land, residential and commercial land, traffic land, and other land. The results also indicate that land use spatial distribution structure affects carbon emission intensity more intensively than energy efficiency and production efficiency do. These conclusions provide valuable reference to develop comprehensive policies for energy conservation and carbon emission reduction in a new perspective.

The role of dispersal mode and habitat specialization for metacommunity structure of shallow beach invertebrates.

PubMed

Rodil, Iván F; Lucena-Moya, Paloma; Jokinen, Henri; Ollus, Victoria; Wennhage, Håkan; Villnäs, Anna; Norkko, Alf

2017-01-01

Metacommunity ecology recognizes the interplay between local and regional patterns in contributing to spatial variation in community structure. In aquatic systems, the relative importance of such patterns depends mainly on the potential connectivity of the specific system. Thus, connectivity is expected to increase in relation to the degree of water movement, and to depend on the specific traits of the study organism. We examined the role of environmental and spatial factors in structuring benthic communities from a highly connected shallow beach network using a metacommunity approach. Both factors contributed to a varying degree to the structure of the local communities suggesting that environmental filters and dispersal-related mechanisms played key roles in determining abundance patterns. We categorized benthic taxa according to their dispersal mode (passive vs. active) and habitat specialization (generalist vs. specialist) to understand the relative importance of environment and dispersal related processes for shallow beach metacommunities. Passive dispersers were predicted by a combination of environmental and spatial factors, whereas active dispersers were not spatially structured and responded only to local environmental factors. Generalists were predicted primarily by spatial factors, while specialists were only predicted by local environmental factors. The results suggest that the role of the spatial component in metacommunity organization is greater in open coastal waters, such as shallow beaches, compared to less-connected environmentally controlled aquatic systems. Our results also reveal a strong environmental role in structuring the benthic metacommunity of shallow beaches. Specifically, we highlight the sensitivity of shallow beach macrofauna to environmental factors related to eutrophication proxies.

Spatial variations in zooplankton community structure along the Japanese coastline in the Japan Sea: influence of the coastal current

NASA Astrophysics Data System (ADS)

Kodama, Taketoshi; Wagawa, Taku; Iguchi, Naoki; Takada, Yoshitake; Takahashi, Takashi; Fukudome, Ken-Ichi; Morimoto, Haruyuki; Goto, Tsuneo

2018-06-01

This study evaluates spatial variations in zooplankton community structure and potential controlling factors along the Japanese coast under the influence of the coastal branch of the Tsushima Warm Current (CBTWC). Variations in the density of morphologically identified zooplankton in the surface layer in May were investigated for a 15-year period. The density of zooplankton (individuals per cubic meter) varied between sampling stations, but there was no consistent west-east trend. Instead, there were different zooplankton community structures in the west and east, with that in Toyama Bay particularly distinct: Corycaeus affinis and Calanus sinicus were dominant in the west and Oithona atlantica was dominant in Toyama Bay. Distance-based redundancy analysis (db-RDA) was used to characterize the variation in zooplankton community structure, and four axes (RD1-4) provided significant explanation. RD2-4 only explained < 4.8 % of variation in the zooplankton community and did not show significant spatial difference; however, RD1, which explained 89.9 % of variation, did vary spatially. Positive and negative species scores on RD1 represent warm- and cold-water species, respectively, and their variation was mainly explained by water column mean temperature, and it is considered to vary spatially with the CBTWC. The CBTWC intrusion to the cold Toyama Bay is weak and occasional due to the submarine canyon structure of the bay. Therefore, the varying bathymetric characteristics along the Japanese coast of the Japan Sea generate the spatial variation in zooplankton community structure, and dominance of warm-water species can be considered an indicator of the CBTWC.

Spatial structure and nutrients promote invasion of IncP-1 plasmids in bacterial populations

PubMed Central

Fox, Randal E; Zhong, Xue; Krone, Stephen M; Top, Eva M

2008-01-01

In spite of the importance of plasmids in bacterial adaptation, we have a poor understanding of their dynamics. It is not known if or how plasmids persist in and spread through (invade) a bacterial population when there is no selection for plasmid-encoded traits. Moreover, the differences in dynamics between spatially structured and mixed populations are poorly understood. Through a joint experimental/theoretical approach, we tested the hypothesis that self-transmissible IncP-1 plasmids can invade a bacterial population in the absence of selection when initially very rare, but only in spatially structured habitats and when nutrients are regularly replenished. Using protocols that differed in the degree of spatial structure and nutrient levels, the invasiveness of plasmid pB10 in Escherichia coli was monitored during at least 15 days, with an initial fraction of plasmid-bearing (p+) cells as low as 10−7. To further explore the mechanisms underlying plasmid dynamics, we developed a spatially explicit mathematical model. When cells were grown on filters and transferred to fresh medium daily, the p+ fraction increased to 13%, whereas almost complete invasion occurred when the population structure was disturbed daily. The plasmid was unable to invade in liquid. When carbon source levels were lower or not replenished, plasmid invasion was hampered. Simulations of the mathematical model closely matched the experimental results and produced estimates of the effects of alternative experimental parameters. This allowed us to isolate the likely mechanisms most responsible for the observations. In conclusion, spatial structure and nutrient availability can be key determinants in the invasiveness of plasmids. PMID:18528415

Reduced fine-scale spatial genetic structure in grazed populations of Dianthus carthusianorum

PubMed Central

Rico, Y; Wagner, H H

2016-01-01

Strong spatial genetic structure in plant populations can increase homozygosity, reducing genetic diversity and adaptive potential. The strength of spatial genetic structure largely depends on rates of seed dispersal and pollen flow. Seeds without dispersal adaptations are likely to be dispersed over short distances within the vicinity of the mother plant, resulting in spatial clustering of related genotypes (fine-scale spatial genetic structure, hereafter spatial genetic structure (SGS)). However, primary seed dispersal by zoochory can promote effective dispersal, increasing the mixing of seeds and influencing SGS within plant populations. In this study, we investigated the effects of seed dispersal by rotational sheep grazing on the strength of SGS and genetic diversity using 11 nuclear microsatellites for 49 populations of the calcareous grassland forb Dianthus carthusianorum. Populations connected by rotational sheep grazing showed significantly weaker SGS and higher genetic diversity than populations in ungrazed grasslands. Independent of grazing treatment, small populations showed significantly stronger SGS and lower genetic diversity than larger populations, likely due to genetic drift. A lack of significant differences in the strength of SGS and genetic diversity between populations that were recently colonized and pre-existing populations suggested that populations colonized after the reintroduction of rotational sheep grazing were likely founded by colonists from diverse source populations. We conclude that dispersal by rotational sheep grazing has the potential to considerably reduce SGS within D. carthusianorum populations. Our study highlights the effectiveness of landscape management by rotational sheep grazing to importantly reduce genetic structure at local scales within restored plant populations. PMID:27381322

Reduced fine-scale spatial genetic structure in grazed populations of Dianthus carthusianorum.

PubMed

Rico, Y; Wagner, H H

2016-11-01

Strong spatial genetic structure in plant populations can increase homozygosity, reducing genetic diversity and adaptive potential. The strength of spatial genetic structure largely depends on rates of seed dispersal and pollen flow. Seeds without dispersal adaptations are likely to be dispersed over short distances within the vicinity of the mother plant, resulting in spatial clustering of related genotypes (fine-scale spatial genetic structure, hereafter spatial genetic structure (SGS)). However, primary seed dispersal by zoochory can promote effective dispersal, increasing the mixing of seeds and influencing SGS within plant populations. In this study, we investigated the effects of seed dispersal by rotational sheep grazing on the strength of SGS and genetic diversity using 11 nuclear microsatellites for 49 populations of the calcareous grassland forb Dianthus carthusianorum. Populations connected by rotational sheep grazing showed significantly weaker SGS and higher genetic diversity than populations in ungrazed grasslands. Independent of grazing treatment, small populations showed significantly stronger SGS and lower genetic diversity than larger populations, likely due to genetic drift. A lack of significant differences in the strength of SGS and genetic diversity between populations that were recently colonized and pre-existing populations suggested that populations colonized after the reintroduction of rotational sheep grazing were likely founded by colonists from diverse source populations. We conclude that dispersal by rotational sheep grazing has the potential to considerably reduce SGS within D. carthusianorum populations. Our study highlights the effectiveness of landscape management by rotational sheep grazing to importantly reduce genetic structure at local scales within restored plant populations.

The role of dispersal mode and habitat specialization for metacommunity structure of shallow beach invertebrates

PubMed Central

Lucena-Moya, Paloma; Jokinen, Henri; Ollus, Victoria; Wennhage, Håkan; Villnäs, Anna; Norkko, Alf

2017-01-01

Metacommunity ecology recognizes the interplay between local and regional patterns in contributing to spatial variation in community structure. In aquatic systems, the relative importance of such patterns depends mainly on the potential connectivity of the specific system. Thus, connectivity is expected to increase in relation to the degree of water movement, and to depend on the specific traits of the study organism. We examined the role of environmental and spatial factors in structuring benthic communities from a highly connected shallow beach network using a metacommunity approach. Both factors contributed to a varying degree to the structure of the local communities suggesting that environmental filters and dispersal-related mechanisms played key roles in determining abundance patterns. We categorized benthic taxa according to their dispersal mode (passive vs. active) and habitat specialization (generalist vs. specialist) to understand the relative importance of environment and dispersal related processes for shallow beach metacommunities. Passive dispersers were predicted by a combination of environmental and spatial factors, whereas active dispersers were not spatially structured and responded only to local environmental factors. Generalists were predicted primarily by spatial factors, while specialists were only predicted by local environmental factors. The results suggest that the role of the spatial component in metacommunity organization is greater in open coastal waters, such as shallow beaches, compared to less-connected environmentally controlled aquatic systems. Our results also reveal a strong environmental role in structuring the benthic metacommunity of shallow beaches. Specifically, we highlight the sensitivity of shallow beach macrofauna to environmental factors related to eutrophication proxies. PMID:28196112

Modeling Spatial Dependencies and Semantic Concepts in Data Mining

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

Vatsavai, Raju

Data mining is the process of discovering new patterns and relationships in large datasets. However, several studies have shown that general data mining techniques often fail to extract meaningful patterns and relationships from the spatial data owing to the violation of fundamental geospatial principles. In this tutorial, we introduce basic principles behind explicit modeling of spatial and semantic concepts in data mining. In particular, we focus on modeling these concepts in the widely used classification, clustering, and prediction algorithms. Classification is the process of learning a structure or model (from user given inputs) and applying the known model to themore » new data. Clustering is the process of discovering groups and structures in the data that are ``similar,'' without applying any known structures in the data. Prediction is the process of finding a function that models (explains) the data with least error. One common assumption among all these methods is that the data is independent and identically distributed. Such assumptions do not hold well in spatial data, where spatial dependency and spatial heterogeneity are a norm. In addition, spatial semantics are often ignored by the data mining algorithms. In this tutorial we cover recent advances in explicitly modeling of spatial dependencies and semantic concepts in data mining.« less

Landscape structure affects specialists but not generalists in naturally fragmented grasslands

USGS Publications Warehouse

Miller, Jesse E.D.; Damschen, Ellen Ingman; Harrison, Susan P.; Grace, James B.

2015-01-01

Understanding how biotic communities respond to landscape spatial structure is critically important for conservation management as natural landscapes become increasingly fragmented. However, empirical studies of the effects of spatial structure on plant species richness have found inconsistent results, suggesting that more comprehensive approaches are needed. In this study, we asked how landscape structure affects total plant species richness and the richness of a guild of specialized plants in a multivariate context. We sampled herbaceous plant communities at 56 dolomite glades (insular, fire-adapted grasslands) across the Missouri Ozarks, and used structural equation modeling (SEM) to analyze the relative importance of landscape structure, soil resource availability, and fire history for plant communities. We found that landscape spatial structure-defined as the area-weighted proximity of glade habitat surrounding study sites (proximity index)-had a significant effect on total plant species richness, but only after we controlled for environmental covariates. Richness of specialist species, but not generalists, was positively related to landscape spatial structure. Our results highlight that local environmental filters must be considered to understand the influence of landscape structure on communities, and that unique species guilds may respond differently to landscape structure than the community as a whole. These findings suggest that both local environment and landscape context should be considered when developing management strategies for species of conservation concern in fragmented habitats.

The spectral signature of cloud spatial structure in shortwave irradiance

PubMed Central

Song, Shi; Schmidt, K. Sebastian; Pilewskie, Peter; King, Michael D.; Heidinger, Andrew K.; Walther, Andi; Iwabuchi, Hironobu; Wind, Gala; Coddington, Odele M.

2017-01-01

In this paper, we used cloud imagery from a NASA field experiment in conjunction with three-dimensional radiative transfer calculations to show that cloud spatial structure manifests itself as a spectral signature in shortwave irradiance fields – specifically in transmittance and net horizontal photon transport in the visible and near-ultraviolet wavelength range. We found a robust correlation between the magnitude of net horizontal photon transport (H) and its spectral dependence (slope), which is scale-invariant and holds for the entire pixel population of a domain. This was surprising at first given the large degree of spatial inhomogeneity. We prove that the underlying physical mechanism for this phenomenon is molecular scattering in conjunction with cloud spatial structure. On this basis, we developed a simple parameterization through a single parameter ε, which quantifies the characteristic spectral signature of spatial inhomogeneities. In the case we studied, neglecting net horizontal photon transport leads to a local transmittance bias of ±12–19 %, even at the relatively coarse spatial resolution of 20 km. Since three-dimensional effects depend on the spatial context of a given pixel in a nontrivial way, the spectral dimension of this problem may emerge as the starting point for future bias corrections. PMID:28824698

The spectral signature of cloud spatial structure in shortwave irradiance.

PubMed

Song, Shi; Schmidt, K Sebastian; Pilewskie, Peter; King, Michael D; Heidinger, Andrew K; Walther, Andi; Iwabuchi, Hironobu; Wind, Gala; Coddington, Odele M

2016-11-08

In this paper, we used cloud imagery from a NASA field experiment in conjunction with three-dimensional radiative transfer calculations to show that cloud spatial structure manifests itself as a spectral signature in shortwave irradiance fields - specifically in transmittance and net horizontal photon transport in the visible and near-ultraviolet wavelength range. We found a robust correlation between the magnitude of net horizontal photon transport ( H ) and its spectral dependence (slope), which is scale-invariant and holds for the entire pixel population of a domain. This was surprising at first given the large degree of spatial inhomogeneity. We prove that the underlying physical mechanism for this phenomenon is molecular scattering in conjunction with cloud spatial structure. On this basis, we developed a simple parameterization through a single parameter ε , which quantifies the characteristic spectral signature of spatial inhomogeneities. In the case we studied, neglecting net horizontal photon transport leads to a local transmittance bias of ±12-19 %, even at the relatively coarse spatial resolution of 20 km. Since three-dimensional effects depend on the spatial context of a given pixel in a nontrivial way, the spectral dimension of this problem may emerge as the starting point for future bias corrections.

Monte Carlo simulation of ionizing radiation induced DNA strand breaks utilizing coarse grained high-order chromatin structures.

PubMed

Liang, Ying; Yang, Gen; Liu, Feng; Wang, Yugang

2016-01-07

Ionizing radiation threatens genome integrity by causing DNA damage. Monte Carlo simulation of the interaction of a radiation track structure with DNA provides a powerful tool for investigating the mechanisms of the biological effects. However, the more or less oversimplification of the indirect effect and the inadequate consideration of high-order chromatin structures in current models usually results in discrepancies between simulations and experiments, which undermine the predictive role of the models. Here we present a biophysical model taking into consideration factors that influence indirect effect to simulate radiation-induced DNA strand breaks in eukaryotic cells with high-order chromatin structures. The calculated yields of single-strand breaks and double-strand breaks (DSBs) for photons are in good agreement with the experimental measurements. The calculated yields of DSB for protons and α particles are consistent with simulations by the PARTRAC code, whereas an overestimation is seen compared with the experimental results. The simulated fragment size distributions for (60)Co γ irradiation and α particle irradiation are compared with the measurements accordingly. The excellent agreement with (60)Co irradiation validates our model in simulating photon irradiation. The general agreement found in α particle irradiation encourages model applicability in the high linear energy transfer range. Moreover, we demonstrate the importance of chromatin high-order structures in shaping the spectrum of initial damage.

An improved spatial contour tree constructed method

NASA Astrophysics Data System (ADS)

Zheng, Yi; Zhang, Ling; Guilbert, Eric; Long, Yi

2018-05-01

Contours are important data to delineate the landform on a map. A contour tree provides an object-oriented description of landforms and can be used to enrich the topological information. The traditional contour tree is used to store topological relationships between contours in a hierarchical structure and allows for the identification of eminences and depressions as sets of nested contours. This research proposes an improved contour tree so-called spatial contour tree that contains not only the topological but also the geometric information. It can be regarded as a terrain skeleton in 3-dimention, and it is established based on the spatial nodes of contours which have the latitude, longitude and elevation information. The spatial contour tree is built by connecting spatial nodes from low to high elevation for a positive landform, and from high to low elevation for a negative landform to form a hierarchical structure. The connection between two spatial nodes can provide the real distance and direction as a Euclidean vector in 3-dimention. In this paper, the construction method is tested in the experiment, and the results are discussed. The proposed hierarchical structure is in 3-demintion and can show the skeleton inside a terrain. The structure, where all nodes have geo-information, can be used to distinguish different landforms and applied for contour generalization with consideration of geographic characteristics.

Nonequilibrium Conditions Explain Spatial Variability in Genetic Structuring of Little Penguin (Eudyptula minor)

PubMed Central

Peucker, Amanda J.; Valautham, Sureen K.; Styan, Craig A.; Dann, Peter

2015-01-01

Factors responsible for spatial structuring of population genetic variation are varied, and in many instances there may be no obvious explanations for genetic structuring observed, or those invoked may reflect spurious correlations. A study of little penguins (Eudyptula minor) in southeast Australia documented low spatial structuring of genetic variation with the exception of colonies at the western limit of sampling, and this distinction was attributed to an intervening oceanographic feature (Bonney Upwelling), differences in breeding phenology, or sea level change. Here, we conducted sampling across the entire Australian range, employing additional markers (12 microsatellites and mitochondrial DNA, 697 individuals, 17 colonies). The zone of elevated genetic structuring previously observed actually represents the eastern half of a genetic cline, within which structuring exists over much shorter spatial scales than elsewhere. Colonies separated by as little as 27 km in the zone are genetically distinguishable, while outside the zone, homogeneity cannot be rejected at scales of up to 1400 km. Given a lack of additional physical or environmental barriers to gene flow, the zone of elevated genetic structuring may reflect secondary contact of lineages (with or without selection against interbreeding), or recent colonization and expansion from this region. This study highlights the importance of sampling scale to reveal the cause of genetic structuring. PMID:25833231

Test Madness

ERIC Educational Resources Information Center

Hedrick, Wanda B., Ed.

2007-01-01

There's accountability and then there's the testing craze an iatrogenic practice that undermines real learning. Hedrick documents the negative effects of testing, giving teachers another weapon in their arsenal against mindless preparation for high-stakes tests.

Individual differences in mental rotation: what does gesture tell us?

PubMed

Göksun, Tilbe; Goldin-Meadow, Susan; Newcombe, Nora; Shipley, Thomas

2013-05-01

Gestures are common when people convey spatial information, for example, when they give directions or describe motion in space. Here, we examine the gestures speakers produce when they explain how they solved mental rotation problems (Shepard and Meltzer in Science 171:701-703, 1971). We asked whether speakers gesture differently while describing their problems as a function of their spatial abilities. We found that low-spatial individuals (as assessed by a standard paper-and-pencil measure) gestured more to explain their solutions than high-spatial individuals. While this finding may seem surprising, finer-grained analyses showed that low-spatial participants used gestures more often than high-spatial participants to convey "static only" information but less often than high-spatial participants to convey dynamic information. Furthermore, the groups differed in the types of gestures used to convey static information: high-spatial individuals were more likely than low-spatial individuals to use gestures that captured the internal structure of the block forms. Our gesture findings thus suggest that encoding block structure may be as important as rotating the blocks in mental spatial transformation.

Revisiting crash spatial heterogeneity: A Bayesian spatially varying coefficients approach.

PubMed

Xu, Pengpeng; Huang, Helai; Dong, Ni; Wong, S C

2017-01-01

This study was performed to investigate the spatially varying relationships between crash frequency and related risk factors. A Bayesian spatially varying coefficients model was elaborately introduced as a methodological alternative to simultaneously account for the unstructured and spatially structured heterogeneity of the regression coefficients in predicting crash frequencies. The proposed method was appealing in that the parameters were modeled via a conditional autoregressive prior distribution, which involved a single set of random effects and a spatial correlation parameter with extreme values corresponding to pure unstructured or pure spatially correlated random effects. A case study using a three-year crash dataset from the Hillsborough County, Florida, was conducted to illustrate the proposed model. Empirical analysis confirmed the presence of both unstructured and spatially correlated variations in the effects of contributory factors on severe crash occurrences. The findings also suggested that ignoring spatially structured heterogeneity may result in biased parameter estimates and incorrect inferences, while assuming the regression coefficients to be spatially clustered only is probably subject to the issue of over-smoothness. Copyright © 2016 Elsevier Ltd. All rights reserved.

Relatedness in spatially structured populations with empty sites: An approach based on spatial moment equations.

PubMed

Lion, Sébastien

2009-09-07

Taking into account the interplay between spatial ecological dynamics and selection is a major challenge in evolutionary ecology. Although inclusive fitness theory has proven to be a very useful tool to unravel the interactions between spatial genetic structuring and selection, applications of the theory usually rely on simplifying demographic assumptions. In this paper, I attempt to bridge the gap between spatial demographic models and kin selection models by providing a method to compute approximations for relatedness coefficients in a spatial model with empty sites. Using spatial moment equations, I provide an approximation of nearest-neighbour relatedness on random regular networks, and show that this approximation performs much better than the ordinary pair approximation. I discuss the connection between the relatedness coefficients I define and those used in population genetics, and sketch some potential extensions of the theory.

Assessing the role of spatial structure on cell-specific activity and interactions within uncultured methane-oxidizing syntrophic consortia (Invited)

NASA Astrophysics Data System (ADS)

Orphan, V. J.; McGlynn, S.; Chadwick, G.; Dekas, A.; Green-Saxena, A.

2013-12-01

Sulfate-coupled anaerobic oxidation of methane is catalysed through symbiotic associations between archaea and sulphate-reducing bacteria and represents the dominant sink for methane in the oceans. These methane-oxidizing symbiotic consortia form well-structured multi-celled aggregations in marine methane seeps, where close spatial proximity is believed to be essential for efficient exchange of substrates between syntrophic partners. The nature of this interspecies metabolic relationship is still unknown however there are a number of hypotheses regarding the electron carrying intermediate and ecophysiology of the partners, each of which should be affected by, and influence, the spatial arrangement of archaeal and bacterial cells within aggregates. To advance our understanding of the role of spatial structure within naturally occurring environmental consortia, we are using spatial statistical methods combined with fluorescence in situ hybridization and high-resolution nanoscale secondary ion mass spectrometry (FISH-nanoSIMS) to quantify the effect of spatial organization and intra- and inter-species interactions on cell-specific microbial activity within these diverse archaeal-bacterial partnerships.

Representing spatial structure through maps and language: Lord of the Rings encodes the spatial structure of middle Earth.

PubMed

Louwerse, Max M; Benesh, Nick

2012-01-01

Spatial mental representations can be derived from linguistic and non-linguistic sources of information. This study tested whether these representations could be formed from statistical linguistic frequencies of city names, and to what extent participants differed in their performance when they estimated spatial locations from language or maps. In a computational linguistic study, we demonstrated that co-occurrences of cities in Tolkien's Lord of the Rings trilogy and The Hobbit predicted the authentic longitude and latitude of those cities in Middle Earth. In a human study, we showed that human spatial estimates of the location of cities were very similar regardless of whether participants read Tolkien's texts or memorized a map of Middle Earth. However, text-based location estimates obtained from statistical linguistic frequencies better predicted the human text-based estimates than the human map-based estimates. These findings suggest that language encodes spatial structure of cities, and that human cognitive map representations can come from implicit statistical linguistic patterns, from explicit non-linguistic perceptual information, or from both. Copyright © 2012 Cognitive Science Society, Inc.

Attending to space within and between objects: Implications from a patient with Balint’s syndrome

PubMed Central

Robertson, Lynn C.; Treisman, Anne

2007-01-01

Neuropsychological conditions such as Balint’s syndrome have shown that perceptual organization of parts into a perceptual unit can be dissociated from the ability to localize objects relative to each other. Neural mechanisms that code the spatial structure within individual objects or words may seem to be intact, while between-object structure is compromised. Here we investigate the nature of within-object spatial processing in a patient with Balint’s syndrome (RM). We suggest that within-object spatial structure can be determined (a) directly by explicit spatial processing of between-part relations, mediated by the same dorsal pathway as between-object spatial relations; or (b) indirectly by the discrimination of object identities, which may involve implicit processing of between-part relations and which is probably mediated by the ventral system. When this route is ruled out, by testing discrimination of differences in part location that do not change the identity of the object, we find no evidence of explicit within-object spatial coding in a patient without functioning parietal lobes. PMID:21049339

Sampling Strategies for Three-Dimensional Spatial Community Structures in IBD Microbiota Research

PubMed Central

Zhang, Shaocun; Cao, Xiaocang; Huang, He

2017-01-01

Identifying intestinal microbiota is arguably an important task that is performed to determine the pathogenesis of inflammatory bowel diseases (IBD); thus, it is crucial to collect and analyze intestinally-associated microbiota. Analyzing a single niche to categorize individuals does not enable researchers to comprehensively study the spatial variations of the microbiota. Therefore, characterizing the spatial community structures of the inflammatory bowel disease microbiome is critical for advancing our understanding of the inflammatory landscape of IBD. However, at present there is no universally accepted consensus regarding the use of specific sampling strategies in different biogeographic locations. In this review, we discuss the spatial distribution when screening sample collections in IBD microbiota research. Here, we propose a novel model, a three-dimensional spatial community structure, which encompasses the x-, y-, and z-axis distributions; it can be used in some sampling sites, such as feces, colonoscopic biopsy, the mucus gel layer, and oral cavity. On the basis of this spatial model, this article also summarizes various sampling and processing strategies prior to and after DNA extraction and recommends guidelines for practical application in future research. PMID:28286741

Assessing the role of spatial correlations during collective cell spreading

PubMed Central

Treloar, Katrina K.; Simpson, Matthew J.; Binder, Benjamin J.; McElwain, D. L. Sean; Baker, Ruth E.

2014-01-01

Spreading cell fronts are essential features of development, repair and disease processes. Many mathematical models used to describe the motion of cell fronts, such as Fisher's equation, invoke a mean–field assumption which implies that there is no spatial structure, such as cell clustering, present. Here, we examine the presence of spatial structure using a combination of in vitro circular barrier assays, discrete random walk simulations and pair correlation functions. In particular, we analyse discrete simulation data using pair correlation functions to show that spatial structure can form in a spreading population of cells either through sufficiently strong cell–to–cell adhesion or sufficiently rapid cell proliferation. We analyse images from a circular barrier assay describing the spreading of a population of MM127 melanoma cells using the same pair correlation functions. Our results indicate that the spreading melanoma cell populations remain very close to spatially uniform, suggesting that the strength of cell–to–cell adhesion and the rate of cell proliferation are both sufficiently small so as not to induce any spatial patterning in the spreading populations. PMID:25026987

Structured Spatial Modeling and Mapping of Domestic Violence Against Women of Reproductive Age in Rwanda.

PubMed

Habyarimana, Faustin; Zewotir, Temesgen; Ramroop, Shaun

2018-03-01

The main objective of this study was to assess the risk factors and spatial correlates of domestic violence against women of reproductive age in Rwanda. A structured spatial approach was used to account for the nonlinear nature of some covariates and the spatial variability on domestic violence. The nonlinear effect was modeled through second-order random walk, and the structured spatial effect was modeled through Gaussian Markov Random Fields specified as an intrinsic conditional autoregressive model. The data from the Rwanda Demographic and Health Survey 2014/2015 were used as an application. The findings of this study revealed that the risk factors of domestic violence against women are the wealth quintile of the household, the size of the household, the husband or partner's age, the husband or partner's level of education, ownership of the house, polygamy, the alcohol consumption status of the husband or partner, the woman's perception of wife-beating attitude, and the use of contraceptive methods. The study also highlighted the significant spatial variation of domestic violence against women at district level.

Spatially encoded phase-contrast MRI-3D MRI movies of 1D and 2D structures at millisecond resolution.

PubMed

Merboldt, Klaus-Dietmar; Uecker, Martin; Voit, Dirk; Frahm, Jens

2011-10-01

This work demonstrates that the principles underlying phase-contrast MRI may be used to encode spatial rather than flow information along a perpendicular dimension, if this dimension contains an MRI-visible object at only one spatial location. In particular, the situation applies to 3D mapping of curved 2D structures which requires only two projection images with different spatial phase-encoding gradients. These phase-contrast gradients define the field of view and mean spin-density positions of the object in the perpendicular dimension by respective phase differences. When combined with highly undersampled radial fast low angle shot (FLASH) and image reconstruction by regularized nonlinear inversion, spatial phase-contrast MRI allows for dynamic 3D mapping of 2D structures in real time. First examples include 3D MRI movies of the acting human hand at a temporal resolution of 50 ms. With an even simpler technique, 3D maps of curved 1D structures may be obtained from only three acquisitions of a frequency-encoded MRI signal with two perpendicular phase encodings. Here, 3D MRI movies of a rapidly rotating banana were obtained at 5 ms resolution or 200 frames per second. In conclusion, spatial phase-contrast 3D MRI of 2D or 1D structures is respective two or four orders of magnitude faster than conventional 3D MRI. Copyright © 2011 Wiley-Liss, Inc.

Some practicable applications of quadtree data structures/representation in astronomy

NASA Technical Reports Server (NTRS)

Pasztor, L.

1992-01-01

Development of quadtree as hierarchical data structuring technique for representing spatial data (like points, regions, surfaces, lines, curves, volumes, etc.) has been motivated to a large extent by storage requirements of images, maps, and other multidimensional (spatially structured) data. For many spatial algorithms, time-efficiency of quadtrees in terms of execution may be as important as their space-efficiency concerning storage conditions. Briefly, the quadtree is a class of hierarchical data structures which is based on the recursive partition of a square region into quadrants and sub-quadrants until a predefined limit. Beyond the wide applicability of quadtrees in image processing, spatial information analysis, and building digital databases (processes becoming ordinary for the astronomical community), there may be numerous further applications in astronomy. Some of these practicable applications based on quadtree representation of astronomical data are presented and suggested for further considerations. Examples are shown for use of point as well as region quadtrees. Statistics of different leaf and non-leaf nodes (homogeneous and heterogeneous sub-quadrants respectively) at different levels may provide useful information on spatial structure of astronomical data in question. By altering the principle guiding the decomposition process, different types of spatial data may be focused on. Finally, a sampling method based on quadtree representation of an image is proposed which may prove to be efficient in the elaboration of sampling strategy in a region where observations were carried out previously either with different resolution or/and in different bands.

Editorial: Spatial arrangement of faults and opening-mode fractures

NASA Astrophysics Data System (ADS)

Laubach, Stephen E.; Lamarche, Juliette; Gauthier, Bertand D. M.; Dunne, William M.

2018-03-01

This issue of the Journal of Structural Geology titled Spatial arrangement of faults and opening-mode fractures explores a fundamental characteristic of fault and fracture arrays. The pattern of fault and opening-mode fracture positions in space defines structural heterogeneity and anisotropy in a rock volume, governs how faults and fractures affect fluid flow, and impacts our understanding of the initiation, propagation and interactions during the formation of fracture patterns. This special issue highlights recent progress with respect to characterizing and understanding the spatial arrangements of fault and fracture patterns, providing examples over a wide range of scales and structural settings.

Modelling Spatial Dependence Structures Between Climate Variables by Combining Mixture Models with Copula Models

NASA Astrophysics Data System (ADS)

Khan, F.; Pilz, J.; Spöck, G.

2017-12-01

Spatio-temporal dependence structures play a pivotal role in understanding the meteorological characteristics of a basin or sub-basin. This further affects the hydrological conditions and consequently will provide misleading results if these structures are not taken into account properly. In this study we modeled the spatial dependence structure between climate variables including maximum, minimum temperature and precipitation in the Monsoon dominated region of Pakistan. For temperature, six, and for precipitation four meteorological stations have been considered. For modelling the dependence structure between temperature and precipitation at multiple sites, we utilized C-Vine, D-Vine and Student t-copula models. For temperature, multivariate mixture normal distributions and for precipitation gamma distributions have been used as marginals under the copula models. A comparison was made between C-Vine, D-Vine and Student t-copula by observational and simulated spatial dependence structure to choose an appropriate model for the climate data. The results show that all copula models performed well, however, there are subtle differences in their performances. The copula models captured the patterns of spatial dependence structures between climate variables at multiple meteorological sites, however, the t-copula showed poor performance in reproducing the dependence structure with respect to magnitude. It was observed that important statistics of observed data have been closely approximated except of maximum values for temperature and minimum values for minimum temperature. Probability density functions of simulated data closely follow the probability density functions of observational data for all variables. C and D-Vines are better tools when it comes to modelling the dependence between variables, however, Student t-copulas compete closely for precipitation. Keywords: Copula model, C-Vine, D-Vine, Spatial dependence structure, Monsoon dominated region of Pakistan, Mixture models, EM algorithm.

(In) Sensitivity to spatial distortion in natural scenes

PubMed Central

Bex, Peter J.

2010-01-01

The perception of object structure in the natural environment is remarkably stable under large variation in image size and projection, especially given our insensitivity to spatial position outside the fovea. Sensitivity to periodic spatial distortions that were introduced into one quadrant of gray-scale natural images was measured in a 4AFC task. Observers were able to detect the presence of distortions in unfamiliar images even though they did not significantly affect the amplitude spectrum. Sensitivity depended on the spatial period of the distortion and on the image structure at the location of the distortion. The results suggest that the detection of distortion involves decisions made in the late stages of image perception and is based on an expectation of the typical structure of natural scenes. PMID:20462324

Liberalism and African Culture.

ERIC Educational Resources Information Center

Sindima, Harvey

1990-01-01

Discusses the effect of liberalism on the African understanding of education, community, and religion. Describes ways in which the European intrusion, that is, colonial governments, schools, and churches, undermined traditional African life and thought. (DM)

Metacommunity theory as a multispecies, multiscale framework for studying the influence of river network structure on riverine communities and ecosystems

USGS Publications Warehouse

Brown, B.L.; Swan, C.M.; Auerbach, D.A.; Campbell, Grant E.H.; Hitt, N.P.; Maloney, K.O.; Patrick, C.

2011-01-01

Explaining the mechanisms underlying patterns of species diversity and composition in riverine networks is challenging. Historically, community ecologists have conceived of communities as largely isolated entities and have focused on local environmental factors and interspecific interactions as the major forces determining species composition. However, stream ecologists have long embraced a multiscale approach to studying riverine ecosystems and have studied both local factors and larger-scale regional factors, such as dispersal and disturbance. River networks exhibit a dendritic spatial structure that can constrain aquatic organisms when their dispersal is influenced by or confined to the river network. We contend that the principles of metacommunity theory would help stream ecologists to understand how the complex spatial structure of river networks mediates the relative influences of local and regional control on species composition. From a basic ecological perspective, the concept is attractive because new evidence suggests that the importance of regional processes (dispersal) depends on spatial structure of habitat and on connection to the regional species pool. The role of local factors relative to regional factors will vary with spatial position in a river network. From an applied perspective, the long-standing view in ecology that local community composition is an indicator of habitat quality may not be uniformly applicable across a river network, but the strength of such bioassessment approaches probably will depend on spatial position in the network. The principles of metacommunity theory are broadly applicable across taxa and systems but seem of particular consequence to stream ecology given the unique spatial structure of riverine systems. By explicitly embracing processes at multiple spatial scales, metacommunity theory provides a foundation on which to build a richer understanding of stream communities.

Evolution at ‘Sutures’ and ‘Centers’: Recombination Can Aid Adaptation of Spatially Structured Populations on Rugged Fitness Landscapes

PubMed Central

Cooper, Jacob D.; Kerr, Benjamin

2016-01-01

Epistatic interactions among genes can give rise to rugged fitness landscapes, in which multiple “peaks” of high-fitness allele combinations are separated by “valleys” of low-fitness genotypes. How populations traverse rugged fitness landscapes is a long-standing question in evolutionary biology. Sexual reproduction may affect how a population moves within a rugged fitness landscape. Sex may generate new high-fitness genotypes by recombination, but it may also destroy high-fitness genotypes by shuffling the genes of a fit parent with a genetically distinct mate, creating low-fitness offspring. Either of these opposing aspects of sex require genotypic diversity in the population. Spatially structured populations may harbor more diversity than well-mixed populations, potentially amplifying both positive and negative effects of sex. On the other hand, spatial structure leads to clumping in which mating is more likely to occur between like types, diminishing the effects of recombination. In this study, we use computer simulations to investigate the combined effects of recombination and spatial structure on adaptation in rugged fitness landscapes. We find that spatially restricted mating and offspring dispersal may allow multiple genotypes inhabiting suboptimal peaks to coexist, and recombination at the “sutures” between the clusters of these genotypes can create genetically novel offspring. Sometimes such an offspring genotype inhabits a new peak on the fitness landscape. In such a case, spatially restricted mating allows this fledgling subpopulation to avoid recombination with distinct genotypes, as mates are more likely to be the same genotype. Such population “centers” can allow nascent peaks to establish despite recombination. Spatial structure may therefore allow an evolving population to enjoy the creative side of sexual recombination while avoiding its destructive side. PMID:27973606

Coupling fine-scale root and canopy structure using ground-based remote sensing

DOE PAGES

Hardiman, Brady S.; Gough, Christopher M.; Butnor, John R.; ...

2017-02-21

Ecosystem physical structure, defined by the quantity and spatial distribution of biomass, influences a range of ecosystem functions. Remote sensing tools permit the non-destructive characterization of canopy and root features, potentially providing opportunities to link above- and belowground structure at fine spatial resolution in functionally meaningful ways. To test this possibility, we employed ground-based portable canopy LiDAR (PCL) and ground penetrating radar (GPR) along co-located transects in forested sites spanning multiple stages of ecosystem development and, consequently, of structural complexity. We examined canopy and root structural data for coherence (i.e., correlation in the frequency of spatial variation) at multiple spatialmore » scales 10 m within each site using wavelet analysis. Forest sites varied substantially in vertical canopy and root structure, with leaf area index and root mass more becoming even vertically as forests aged. In all sites, above- and belowground structure, characterized as mean maximum canopy height and root mass, exhibited significant coherence at a scale of 3.5–4 m, and results suggest that the scale of coherence may increase with stand age. Our findings demonstrate that canopy and root structure are linked at characteristic spatial scales, which provides the basis to optimize scales of observation. Lastly, our study highlights the potential, and limitations, for fusing LiDAR and radar technologies to quantitatively couple above- and belowground ecosystem structure.« less

Coupling fine-scale root and canopy structure using ground-based remote sensing

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

Hardiman, Brady S.; Gough, Christopher M.; Butnor, John R.

Ecosystem physical structure, defined by the quantity and spatial distribution of biomass, influences a range of ecosystem functions. Remote sensing tools permit the non-destructive characterization of canopy and root features, potentially providing opportunities to link above- and belowground structure at fine spatial resolution in functionally meaningful ways. To test this possibility, we employed ground-based portable canopy LiDAR (PCL) and ground penetrating radar (GPR) along co-located transects in forested sites spanning multiple stages of ecosystem development and, consequently, of structural complexity. We examined canopy and root structural data for coherence (i.e., correlation in the frequency of spatial variation) at multiple spatialmore » scales 10 m within each site using wavelet analysis. Forest sites varied substantially in vertical canopy and root structure, with leaf area index and root mass more becoming even vertically as forests aged. In all sites, above- and belowground structure, characterized as mean maximum canopy height and root mass, exhibited significant coherence at a scale of 3.5–4 m, and results suggest that the scale of coherence may increase with stand age. Our findings demonstrate that canopy and root structure are linked at characteristic spatial scales, which provides the basis to optimize scales of observation. Lastly, our study highlights the potential, and limitations, for fusing LiDAR and radar technologies to quantitatively couple above- and belowground ecosystem structure.« less

Event schemas in autism spectrum disorders: the role of theory of mind and weak central coherence.

PubMed

Loth, Eva; Gómez, Juan Carlos; Happé, Francesca

2008-03-01

Event schemas (generalized knowledge of what happens at common real-life events, e.g., a birthday party) are an important cognitive tool for social understanding: They provide structure for social experiences while accounting for many variable aspects. Using an event narratives task, this study tested the hypotheses that theory of mind (ToM) deficits and weak central coherence (WCC, a local processing bias) undermine different aspects of event knowledge in people with autism spectrum disorder (ASD). Event narratives of ASD ToM-failers were overall significantly impaired. ASD ToM-passers showed more specific abnormalities relating to variable activities, and some of these were significantly associated to WCC. Abnormalities in event knowledge might help linking ASD-typical social deficits in real-life situations and the adherence to inflexible routines.

Has competition lowered hospital prices?

PubMed

Zwanziger, Jack; Mooney, Cathleen

2005-01-01

On Jan. 1, 1997, New York ended its regulation of hospital prices with the intent of using competitive markets to control prices and increase efficiency. This paper uses data that come from annual reports filed by all health maintenance organizations (HMOs) operating in New York and include payments to and usage in the major hospitals in an HMO's network. We estimate the relationship between implied prices and hospital, plan, and market characteristics. The models show that after 1997, hospitals in more competitive markets paid less. Partially offsetting these price reductions were price increases associated with hospital mergers that reduced the competitiveness of the local market. Hospital deregulation was successful, at least in the short run, in using price competition to reduce hospital payments; it is unclear whether this success will be undermined by the structural changes taking place in the hospital industry.

Positioning positivism, critical realism and social constructionism in the health sciences: a philosophical orientation.

PubMed

Cruickshank, Justin

2012-03-01

Positioning positivism, critical realism and social constructionism in the health sciences: a philosophical orientation This article starts by considering the differences within the positivist tradition and then it moves on to compare two of the most prominent schools of postpositivism, namely critical realism and social constructionism. Critical realists hold, with positivism, that knowledge should be positively applied, but reject the positivist method for doing this, arguing that causal explanations have to be based not on empirical regularities but on references to unobservable structures. Social constructionists take a different approach to postpositivism and endorse a relativist rejection of truth and hold that the task of research is to foster a scepticism that undermines any positive truth claim made. It is argued that social constructionism is a contradictory position. © 2011 Blackwell Publishing Ltd.

Neurobiology of Schizophrenia: Search for the Elusive Correlation with Symptoms

PubMed Central

Mathalon, Daniel H.; Ford, Judith M.

2012-01-01

In the last half-century, human neuroscience methods provided a way to study schizophrenia in vivo, and established that it is associated with subtle abnormalities in brain structure and function. However, efforts to understand the neurobiological bases of the clinical symptoms that the diagnosis is based on have been largely unsuccessful. In this paper, we provide an overview of the conceptual and methodological obstacles that undermine efforts to link the severity of specific symptoms to specific neurobiological measures. These obstacles include small samples, questionable reliability and validity of measurements, medication confounds, failure to distinguish state and trait effects, correlation–causation ambiguity, and the absence of compelling animal models of specific symptoms to test mechanistic hypotheses derived from brain-symptom correlations. We conclude with recommendations to promote progress in establishing brain-symptom relationships. PMID:22654745

Chemical tailoring of teicoplanin with site-selective reactions.

PubMed

Pathak, Tejas P; Miller, Scott J

2013-06-05

Semisynthesis of natural product derivatives combines the power of fermentation with orthogonal chemical reactions. Yet, chemical modification of complex structures represents an unmet challenge, as poor selectivity often undermines efficiency. The complex antibiotic teicoplanin eradicates bacterial infections. However, as resistance emerges, the demand for improved analogues grows. We have discovered chemical reactions that achieve site-selective alteration of teicoplanin. Utilizing peptide-based additives that alter reaction selectivities, certain bromo-teicoplanins are accessible. These new compounds are also scaffolds for selective cross-coupling reactions, enabling further molecular diversification. These studies enable two-step access to glycopeptide analogues not available through either biosynthesis or rapid total chemical synthesis alone. The new compounds exhibit a spectrum of activities, revealing that selective chemical alteration of teicoplanin may lead to analogues with attenuated or enhanced antibacterial properties, in particular against vancomycin- and teicoplanin-resistant strains.

Administrative records and surveys as basis for statistics on international labour migration.

PubMed

Hoffmann, E

1997-08-01

"This paper discusses possible sources for statistics to be used for describing and analysing the number, structure, situation, development and impact of migrant workers. The discussion is focused on key, intrinsic features of the different sources, important for the understanding of their strengths and weaknesses, and draws the reader's attention to features which may tend to undermine the quality of statistics produced as well as ways in which the impact of such features can be evaluated and, if possible, reduced.... The paper is organized around three key groups of migrant workers: (a) Persons who are arriving in a country to work there, i.e. the inflow of foreign workers; (b) Persons who are leaving their country to find work abroad, i.e. the outflow of migrant workers; [and] (c) Stock of foreign workers in the country." (EXCERPT)

Subversion of cytokine networks by virally encoded decoy receptors

PubMed Central

Epperson, Megan L.; Lee, Chung A.; Fremont, Daved H.

2012-01-01

Summary During the course of evolution, viruses have captured or created a diverse array of open reading frames that encode for proteins that serve to evade and sabotage the host innate and adaptive immune responses, which would otherwise lead to their elimination. These viral genomes are some of the best textbooks of immunology ever written. The established arsenal of immunomodulatory proteins encoded by viruses is large and growing and includes specificities for virtually all known inflammatory pathways and targets. The focus of this review is on herpes and poxvirus-encoded cytokine and chemokine binding proteins that serve to undermine the coordination of host immune surveillance. Structural and mechanistic studies of these decoy receptors have provided a wealth of information, not only about viral pathogenesis but also about the inner workings of cytokine signaling networks. PMID:23046131

Flood scour monitoring system using fiber Bragg grating sensors

NASA Astrophysics Data System (ADS)

Lin, Yung Bin; Lai, Jihn Sung; Chang, Kuo Chun; Li, Lu Sheng

2006-12-01

The exposure and subsequent undermining of pier/abutment foundations through the scouring action of a flood can result in the structural failure of a bridge. Bridge scour is one of the leading causes of bridge failure. Bridges subject to periods of flood/high flow require monitoring during those times in order to protect the traveling public. In this study, an innovative scour monitoring system using button-like fiber Bragg grating (FBG) sensors was developed and applied successfully in the field during the Aere typhoon period in 2004. The in situ FBG scour monitoring system has been demonstrated to be robust and reliable for real-time scour-depth measurements, and to be valid for indicating depositional depth at the Dadu Bridge. The field results show that this system can function well and survive a typhoon flood.

Public purchasing and private priorities for healthcare in New Zealand.

PubMed

Howden-Chapman, P; Ashton, T

2000-11-01

The 1993 Health and Disability Services Act heralded a range of structural reforms in the New Zealand health care system. Despite these reforms considerable resources being spent on convincing consumers of their merits, have failed to gain widespread public approval. This paper examines two key issues that have arisen during the reform process. These are the difficulties associated with trying to set priorities in ways which are effective and politically acceptable, and the relationship between the public and private sectors. Unacknowledged conflicts of interest have helped to undermine the priority setting process. The discussion suggests that it may be increasingly difficult for any government in future to determine the allocation of resources without taking private sector interests and rising public concern into account. It remains to be seen which of these factors is more powerful.

Religiousness, religious doubt, and death anxiety.

PubMed

Henrie, James; Patrick, Julie Hicks

2014-01-01

Terror Management Theory (TMT) (Greenberg, Pyszczynski, & Solomon, 1986) suggests that culturally-provided worldviews (e.g., religion) may protect individuals from experiencing death anxiety, and several studies have supported this position. However, if one's worldview can offer protection, doubts concerning one's worldview could undermine this protection. The current study investigated whether age, gender, religiousness, and religious doubt were associated with death anxiety. Using data from 635 younger, middle-aged, and older adults, a structural equation model with age, gender, religiousness, and religious doubt predicting death anxiety was tested. The model had a good fit (chi2 (76) = 193.467, p < .001; GFI = .961, CFI = .976, TLI = .967, RMSEA = .049) and accounted for 12.3% of the variance in death anxiety. Results were consistent with TMT, as religiousness was inversely associated with death anxiety, while religious doubt was positively associated with death anxiety.

Fourier Domain Sensing

NASA Technical Reports Server (NTRS)

Feldkhun, Daniel (Inventor); Wagner, Kelvin H. (Inventor)

2013-01-01

Methods and systems are disclosed of sensing an object. A first radiation is spatially modulated to generate a structured second radiation. The object is illuminated with the structured second radiation such that the object produces a third radiation in response. Apart from any spatially dependent delay, a time variation of the third radiation is spatially independent. With a single-element detector, a portion of the third radiation is detected from locations on the object simultaneously. At least one characteristic of a sinusoidal spatial Fourier-transform component of the object is estimated from a time-varying signal from the detected portion of the third radiation.

Spatial Data Transfer Standard (SDTS)

USGS Publications Warehouse

,

1995-01-01

The Spatial Data Transfer Standard (SOTS) is a mechanism for the transfer of spatial data between dissimilar computer systems. The SOTS specifies exchange constructs, addressing formats, structure, and content for spatially referenced vector and raster (including gridded) data. SOTS components are a conceptual model, specifications for a quality report, transfer module specifications, data dictionary specifications, and definitions of spatial features and attributes.

Structure and biodiversity of coralligenous assemblages dominated by the precious red coral Corallium rubrum over broad spatial scales

PubMed Central

Casas-Güell, Edgar; Cebrian, Emma; Garrabou, Joaquim; Ledoux, Jean-Baptiste; Linares, Cristina; Teixidó, Núria

2016-01-01

Data on species diversity and structure in coralligenous outcrops dominated by Corallium rubrum are lacking. A hierarchical sampling including 3 localities and 9 sites covering more than 400 km of rocky coasts in NW Mediterranean, was designed to characterize the spatial variability of structure, composition and diversity of perennial species inhabiting coralligenous outcrops. We estimated species/taxa composition and abundance. Eight morpho-functional groups were defined according to their life span and growth to characterize the structural complexity of the outcrops. The species composition and structural complexity differed consistently across all spatial scales considered. The lowest and the highest variability were found among localities (separated by >200 km) and within sites (separated by 1–5 km), respectively supporting differences in diversity indices. The morpho-functional groups displayed a consistent spatial arrangement in terms of the number, size and shape of patches across study sites. These results contribute to filling the gap on the understanding of assemblage composition and structure and to build baselines to assess the response of this of this highly threatened habitat to anthropogenic disturbances. PMID:27857209

A New Stratified Sampling Procedure which Decreases Error Estimation of Varroa Mite Number on Sticky Boards.

PubMed

Kretzschmar, A; Durand, E; Maisonnasse, A; Vallon, J; Le Conte, Y

2015-06-01

A new procedure of stratified sampling is proposed in order to establish an accurate estimation of Varroa destructor populations on sticky bottom boards of the hive. It is based on the spatial sampling theory that recommends using regular grid stratification in the case of spatially structured process. The distribution of varroa mites on sticky board being observed as spatially structured, we designed a sampling scheme based on a regular grid with circles centered on each grid element. This new procedure is then compared with a former method using partially random sampling. Relative error improvements are exposed on the basis of a large sample of simulated sticky boards (n=20,000) which provides a complete range of spatial structures, from a random structure to a highly frame driven structure. The improvement of varroa mite number estimation is then measured by the percentage of counts with an error greater than a given level. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The Deprofessionalization of Social Work

ERIC Educational Resources Information Center

Specht, Harry

1972-01-01

Four ideological currents serve to undermine professionalism in social work: activism, anti-individualism, communalism, and environmentalism. The author describes each of these currents and discusses the ways in which social work education accommodates them. (Author)

Spatial Structure of Seagrass Suggests That Size-Dependent Plant Traits Have a Strong Influence on the Distribution and Maintenance of Tropical Multispecies Meadows

PubMed Central

Ooi, Jillian L. S.; Van Niel, Kimberly P.; Kendrick, Gary A.; Holmes, Karen W.

2014-01-01

Background Seagrass species in the tropics occur in multispecies meadows. How these meadows are maintained through species co-existence and what their ecological drivers may be has been an overarching question in seagrass biogeography. In this study, we quantify the spatial structure of four co-existing species and infer potential ecological processes from these structures. Methods and Results Species presence/absence data were collected using underwater towed and dropped video cameras in Pulau Tinggi, Malaysia. The geostatistical method, utilizing semivariograms, was used to describe the spatial structure of Halophila spp, Halodule uninervis, Syringodium isoetifolium and Cymodocea serrulata. Species had spatial patterns that were oriented in the along-shore and across-shore directions, nested with larger species in meadow interiors, and consisted of multiple structures that indicate the influence of 2–3 underlying processes. The Linear Model of Coregionalization (LMC) was used to estimate the amount of variance contributing to the presence of a species at specific spatial scales. These distances were <2.5 m (micro-scale), 2.5–50 m (fine-scale) and >50 m (broad-scale) in the along-shore; and <2.5 m (micro-scale), 2.5–140 m (fine-scale) and >140 m (broad-scale) in the across-shore. The LMC suggests that smaller species (Halophila spp and H. uninervis) were most influenced by broad-scale processes such as hydrodynamics and water depth whereas large, localised species (S. isoetifolium and C. serrulata) were more influenced by finer-scale processes such as sediment burial, seagrass colonization and growth, and physical disturbance. Conclusion In this study, we provide evidence that spatial structure is distinct even when species occur in well-mixed multispecies meadows, and we suggest that size-dependent plant traits have a strong influence on the distribution and maintenance of tropical marine plant communities. This study offers a contrast from previous spatial models of seagrasses which have largely focused on monospecific temperate meadows. PMID:24497978

Spatial structure of seagrass suggests that size-dependent plant traits have a strong influence on the distribution and maintenance of tropical multispecies meadows.

PubMed

Ooi, Jillian L S; Van Niel, Kimberly P; Kendrick, Gary A; Holmes, Karen W

2014-01-01

Seagrass species in the tropics occur in multispecies meadows. How these meadows are maintained through species co-existence and what their ecological drivers may be has been an overarching question in seagrass biogeography. In this study, we quantify the spatial structure of four co-existing species and infer potential ecological processes from these structures. Species presence/absence data were collected using underwater towed and dropped video cameras in Pulau Tinggi, Malaysia. The geostatistical method, utilizing semivariograms, was used to describe the spatial structure of Halophila spp, Halodule uninervis, Syringodium isoetifolium and Cymodocea serrulata. Species had spatial patterns that were oriented in the along-shore and across-shore directions, nested with larger species in meadow interiors, and consisted of multiple structures that indicate the influence of 2-3 underlying processes. The Linear Model of Coregionalization (LMC) was used to estimate the amount of variance contributing to the presence of a species at specific spatial scales. These distances were <2.5 m (micro-scale), 2.5-50 m (fine-scale) and >50 m (broad-scale) in the along-shore; and <2.5 m (micro-scale), 2.5-140 m (fine-scale) and >140 m (broad-scale) in the across-shore. The LMC suggests that smaller species (Halophila spp and H. uninervis) were most influenced by broad-scale processes such as hydrodynamics and water depth whereas large, localised species (S. isoetifolium and C. serrulata) were more influenced by finer-scale processes such as sediment burial, seagrass colonization and growth, and physical disturbance. In this study, we provide evidence that spatial structure is distinct even when species occur in well-mixed multispecies meadows, and we suggest that size-dependent plant traits have a strong influence on the distribution and maintenance of tropical marine plant communities. This study offers a contrast from previous spatial models of seagrasses which have largely focused on monospecific temperate meadows.

Financial motivation undermines potential enjoyment in an intensive diet and activity intervention.

PubMed

Moller, Arlen C; Buscemi, Joanna; McFadden, H Gene; Hedeker, Donald; Spring, Bonnie

2014-10-01

The use of material incentives in healthy lifestyle interventions is becoming widespread. However, self-determination theory (SDT) posits that when material incentives are perceived as controlling, they undermine intrinsic motivation. We analyzed data from the Make Better Choices trial-a trial testing strategies for improving four risk behaviors: low fruit-vegetable intake, high saturated fat intake, low physical activity, and high sedentary activity. At baseline, participants reported the degree to which financial incentives were an important motivator (financial motivation); self-reported enjoyment of each behavior was assessed before and after the 3-week incentivization phase. Consistent with SDT, after controlling for general motivation and group assignment, lower financial motivation predicted more adaptive changes in enjoyment. Whereas participants low in financial motivation experienced adaptive changes, adaptive changes were suppressed among those high in financial motivation.

Financial motivation undermines potential enjoyment in an intensive diet and activity intervention

PubMed Central

Moller, Arlen C.; Buscemi, Joanna; McFadden, H. Gene; Hedeker, Donald; Spring, Bonnie

2013-01-01

The use of material incentives in healthy lifestyle interventions is becoming widespread. However, self-determination theory (SDT) posits that when material incentives are perceived as controlling, they undermine intrinsic motivation. We analyzed data from the Make Better Choices trial—a trial testing strategies for improving four risk behaviors: low fruit–vegetable intake, high saturated fat intake, low physical activity, and high sedentary activity. At baseline, participants reported the degree to which financial incentives were an important motivator (financial motivation); self-reported enjoyment of each behavior was assessed before and after the 3-week incentivization phase. Consistent with SDT, after controlling for general motivation and group assignment, lower financial motivation predicted more adaptive changes in enjoyment. Whereas participants low in financial motivation experienced adaptive changes, adaptive changes were suppressed among those high in financial motivation. PMID:24142187

Soft drink "pouring rights": marketing empty calories to children.

PubMed

Nestle, M

2000-01-01

Healthy People 2010 objectives call for meals and snacks served in schools to contribute to overall diets that meet federal dietary guidelines. Sales in schools of foods and drinks high in calories and low in nutrients undermine this health objective, as well as participation in the more nutritious, federally sponsored, school lunch programs. Competitive foods also undermine nutrition information taught in the classroom. Lucrative contracts between school districts and soft drink companies for exclusive rights to sell one brand are the latest development in the increasing commercialization of school food. These contracts, intended to elicit brand loyalty among young children who have a lifetime of purchases ahead of them, are especially questionable because they place schools in the position of "pushing" soft drink consumption. "Pouring rights" contracts deserve attention from public health professionals concerned about the nutritional quality of children's diets.

Passive Facebook usage undermines affective well-being: Experimental and longitudinal evidence.

PubMed

Verduyn, Philippe; Lee, David Seungjae; Park, Jiyoung; Shablack, Holly; Orvell, Ariana; Bayer, Joseph; Ybarra, Oscar; Jonides, John; Kross, Ethan

2015-04-01

Prior research indicates that Facebook usage predicts declines in subjective well-being over time. How does this come about? We examined this issue in 2 studies using experimental and field methods. In Study 1, cueing people in the laboratory to use Facebook passively (rather than actively) led to declines in affective well-being over time. Study 2 replicated these findings in the field using experience-sampling techniques. It also demonstrated how passive Facebook usage leads to declines in affective well-being: by increasing envy. Critically, the relationship between passive Facebook usage and changes in affective well-being remained significant when controlling for active Facebook use, non-Facebook online social network usage, and direct social interactions, highlighting the specificity of this result. These findings demonstrate that passive Facebook usage undermines affective well-being. (c) 2015 APA, all rights reserved).

Neuroscience and Ethics.

PubMed

Liao, S Matthew

2017-03-01

A number of people believe that results from neuroscience have the potential to settle seemingly intractable debates concerning the nature, practice, and reliability of moral judgments. In particular, Joshua Greene has argued that evidence from neuroscience can be used to advance the long-standing debate between consequentialism and deontology. This paper first argues that charitably interpreted, Greene's neuroscientific evidence can contribute to substantive ethical discussions by being part of an epistemic debunking argument. It then argues that taken as an epistemic debunking argument, Greene's argument falls short in undermining deontological judgments. Lastly, it proposes that accepting Greene's methodology at face value, neuroimaging results may in fact call into question the reliability of consequentialist judgments. The upshot is that Greene's empirical results do not undermine deontology and that Greene's project points toward a way by which empirical evidence such as neuroscientific evidence can play a role in normative debates.

Committee Opinion No. 683: Behavior That Undermines a Culture of Safety.

PubMed

2017-01-01

A key element of an organizational safety culture is maintaining an environment of professionalism that encourages communication and promotes high-quality care. Behavior that undermines a culture of safety, including disruptive or intimidating behavior, has a negative effect on the quality and safety of patient care. Intimidating behavior and disruptive behavior are unprofessional and should not be tolerated. Confronting disruptive individuals is difficult. Co-workers often are reluctant to report disruptive behavior because of fear of retaliation and the stigma associated with "blowing the whistle" on a colleague. Additionally, negative behavior of revenue-generating physicians may be overlooked because of concern about the perceived consequences of confronting them. The Joint Commission requires that hospitals establish a code of conduct that "defines acceptable behavior and behavior that undermines a culture of safety." Clear standards of behavior that acknowledge the consequences of disruptive and intimidating behavior must be established and communicated. Institutions and practices should develop a multifaceted approach to address disruptive behavior. Confidential reporting systems and assistance programs for physicians who exhibit disruptive behavior should be established. A concerted effort should be made within each organization to educate staff (ie, medical, nursing, and ancillary staff) about the potential negative effects of disruptive and inappropriate behavior. A clearly delineated hospital-wide policy and procedure relating to disruptive behavior should be developed and enforced by hospital administration. To preserve professional standing, physicians should understand how to respond to and mitigate the effect of complaints or reports.

A conceptually new treatment approach for relapsed glioblastoma: Coordinated undermining of survival paths with nine repurposed drugs (CUSP9) by the International Initiative for Accelerated Improvement of Glioblastoma Care

PubMed Central

Kast, Richard E.; Boockvar, John A.; Brüning, Ansgar; Cappello, Francesco; Chang, Wen-Wei; Cvek, Boris; Dou, Q. Ping; Duenas-Gonzalez, Alfonso; Efferth, Thomas; Focosi, Daniele; Ghaffari, Seyed H.; Karpel-Massler, Georg; Ketola, Kirsi; Khoshnevisan, Alireza; Keizman, Daniel; Magné, Nicolas; Marosi, Christine; McDonald, Kerrie; Muñoz, Miguel; Paranjpe, Ameya; Pourgholami, Mohammad H.; Sardi, Iacopo; Sella, Avishay; Srivenugopal, Kalkunte S.; Tuccori, Marco; Wang, Weiguang; Wirtz, Christian R.; Halatsch, Marc-Eric

2013-01-01

To improve prognosis in recurrent glioblastoma we developed a treatment protocol based on a combination of drugs not traditionally thought of as cytotoxic chemotherapy agents but that have a robust history of being well-tolerated and are already marketed and used for other non-cancer indications. Focus was on adding drugs which met these criteria: a) were pharmacologically well characterized, b) had low likelihood of adding to patient side effect burden, c) had evidence for interfering with a recognized, well-characterized growth promoting element of glioblastoma, and d) were coordinated, as an ensemble had reasonable likelihood of concerted activity against key biological features of glioblastoma growth. We found nine drugs meeting these criteria and propose adding them to continuous low dose temozolomide, a currently accepted treatment for relapsed glioblastoma, in patients with recurrent disease after primary treatment with the Stupp Protocol. The nine adjuvant drug regimen, Coordinated Undermining of Survival Paths, CUSP9, then are aprepitant, artesunate, auranofin, captopril, copper gluconate, disulfiram, ketoconazole, nelfinavir, sertraline, to be added to continuous low dose temozolomide. We discuss each drug in turn and the specific rationale for use- how each drug is expected to retard glioblastoma growth and undermine glioblastoma's compensatory mechanisms engaged during temozolomide treatment. The risks of pharmacological interactions and why we believe this drug mix will increase both quality of life and overall survival are reviewed. PMID:23594434

Conflict in Men’s Experiences With Antidepressants

PubMed Central

Gibson, Kerry; Cartwright, Claire; Read, John

2016-01-01

While men’s experiences of depression and help seeking are known to be shaped by gender, there is little research which examines their experience of using antidepressants to treat this. This study is based on in-depth, narrative-style interviews with 20 New Zealand men who had used antidepressants. The analysis identified a number of areas of conflict in the men’s accounts of using this medication. Conflict centered on the way taking antidepressants was seen as undermining personal control while also allowing users to take charge of their problems; facilitating general functioning while undermining sexual functioning; relieving emotional distress while undermining emotional vitality; and the tension participants felt between making autonomous judgments about the value of antidepressants and relying on the “expertise” of others. Participants negotiated these conflicts in a variety of ways. In some cases, antidepressants were positioned as being able to affirm aspects of traditional masculinity, while a smaller number of participants managed these conflicts by redefining aspects of their own masculinity in ways that contrasted with dominant constructions. This research is limited by the sample of older, more privileged men in the context of New Zealand culture which favors macho forms of masculinity. In similar contexts, mental health practitioners should be mindful of the conflicts that men might experience in relation to their antidepressant use. Facilitating men’s exploration of these issues may enable them to make better decisions about treatment options or to provide more effective support to those who have opted for antidepressant treatment. PMID:26993998

Health worker motivation in the context of HIV care and treatment challenges in Mbeya Region, Tanzania: A qualitative study

PubMed Central

2011-01-01

Background Health worker motivation can potentially affect the provision of health services. The HIV pandemic has placed additional strain on health service provision through the extra burden of increased testing and counselling, treating opportunistic infections and providing antiretroviral treatment. The aim of this paper is to explore the challenges generated by HIV care and treatment and their impact on health worker motivation in Mbeya Region, Tanzania. Methods Thirty in-depth interviews were conducted with health workers across the range of health care professions in health facilities in two high HIV-prevalence districts of Mbeya Region, Tanzania. A qualitative framework analysis was adopted for data analysis. Results The negative impact of HIV-related challenges on health worker motivation was confirmed by this study. Training seminars and workshops related to HIV contributed to the shortage of health workers in the facilities. Lower status workers were frequently excluded from training and were more severely affected by the consequent increase in workload as seminars were usually attended by higher status professionals who controlled access. Constant and consistent complaints by clients have undermined health workers' expectations of trust and recognition. Health workers were forced to take responsibility for dealing with problems arising from organisational inefficiencies within the health system. Conclusion HIV-related challenges undermine motivation among health workers in Mbeya, Tanzania with the burden falling most heavily on lower status workers. Strained relations between health workers and the community they serve, further undermine motivation of health workers. PMID:21992700

Alternative spatial configurations to reflect landscape structure in a hydrological model: SUMMA applications to the Reynolds Creek Watershed and the Columbia River Basin

NASA Astrophysics Data System (ADS)

Nijssen, Bart; Clark, Martyn; Mizukami, Naoki; Chegwidden, Oriana

2016-04-01

Most existing hydrological models use a fixed representation of landscape structure. For example, high-resolution, spatially-distributed models may use grid cells that exchange moisture through the saturated subsurface or may divide the landscape into hydrologic response units that only exchange moisture through surface channels. Alternatively, many regional models represent the landscape through coarse elements that do not model any moisture exchange between these model elements. These spatial organizations are often represented at a low-level in the model code and its data structures, which makes it difficult to evaluate different landscape representations using the same hydrological model. Instead, such experimentation requires the use of multiple, different hydrological models, which in turn complicates the analysis, because differences in model outcomes are no longer constrained by differing spatial representations. This inflexibility in the representation of landscape structure also limits a model's capability for scaling local processes to regional outcomes. In this study, we used the Structure for Unifying Multiple Modeling Alternatives (SUMMA) to evaluate different model spatial configurations to represent landscape structure and to evaluate scaling behavior. SUMMA can represent the moisture exchange between arbitrarily shaped landscape elements in a number of different ways, while using the same model parameterizations for vertical fluxes. This allows us to isolate the effects of changes in landscape representations on modeled hydrological fluxes and states. We examine the effects of spatial configuration in Reynolds Creek, Idaho, USA, which is a research watershed with gaged areas from 1-20 km2. We then use the same modeling system to evaluate scaling behavior in simulated hydrological fluxes in the Columbia River Basin, Pacific Northwest, USA. This basin drains more than 500,000 km2 and includes the Reynolds Creek Watershed.

High spatial resolution mapping of folds and fractures using Unmanned Aerial Vehicle (UAV) photogrammetry

NASA Astrophysics Data System (ADS)

Cruden, A. R.; Vollgger, S.

2016-12-01

The emerging capability of UAV photogrammetry combines a simple and cost-effective method to acquire digital aerial images with advanced computer vision algorithms that compute spatial datasets from a sequence of overlapping digital photographs from various viewpoints. Depending on flight altitude and camera setup, sub-centimeter spatial resolution orthophotographs and textured dense point clouds can be achieved. Orientation data can be collected for detailed structural analysis by digitally mapping such high-resolution spatial datasets in a fraction of time and with higher fidelity compared to traditional mapping techniques. Here we describe a photogrammetric workflow applied to a structural study of folds and fractures within alternating layers of sandstone and mudstone at a coastal outcrop in SE Australia. We surveyed this location using a downward looking digital camera mounted on commercially available multi-rotor UAV that autonomously followed waypoints at a set altitude and speed to ensure sufficient image overlap, minimum motion blur and an appropriate resolution. The use of surveyed ground control points allowed us to produce a geo-referenced 3D point cloud and an orthophotograph from hundreds of digital images at a spatial resolution < 10 mm per pixel, and cm-scale location accuracy. Orientation data of brittle and ductile structures were semi-automatically extracted from these high-resolution datasets using open-source software. This resulted in an extensive and statistically relevant orientation dataset that was used to 1) interpret the progressive development of folds and faults in the region, and 2) to generate a 3D structural model that underlines the complex internal structure of the outcrop and quantifies spatial variations in fold geometries. Overall, our work highlights how UAV photogrammetry can contribute to new insights in structural analysis.

Benefits of incorporating spatial organisation of catchments for a semi-distributed hydrological model

NASA Astrophysics Data System (ADS)

Schumann, Andreas; Oppel, Henning

2017-04-01

To represent the hydrological behaviour of catchments a model should reproduce/reflect the hydrologically most relevant catchment characteristics. These are heterogeneously distributed within a watershed but often interrelated and subject of a certain spatial organisation. Since common models are mostly based on fundamental assumptions about hydrological processes, the reduction of variance of catchment properties as well as the incorporation of the spatial organisation of the catchment is desirable. We have developed a method that combines the idea of the width-function used for determination of the geomorphologic unit hydrograph with information about soil or topography. With this method we are able to assess the spatial organisation of selected catchment characteristics. An algorithm was developed that structures a watershed into sub-basins and other spatial units to minimise its heterogeneity. The outcomes of this algorithm are used for the spatial setup of a semi-distributed model. Since the spatial organisation of a catchment is not bound to a single characteristic, we have to embed information of multiple catchment properties. For this purpose we applied a fuzzy-based method to combine the spatial setup for multiple single characteristics into a union, optimal spatial differentiation. Utilizing this method, we are able to propose a spatial structure for a semi-distributed hydrological model, comprising the definition of sub-basins and a zonal classification within each sub-basin. Besides the improved spatial structuring, the performed analysis ameliorates modelling in another way. The spatial variability of catchment characteristics, which is considered by a minimum of heterogeneity in the zones, can be considered in a parameter constrained calibration scheme in a case study both options were used to explore the benefits of incorporating the spatial organisation and derived parameter constraints for the parametrisation of a HBV-96 model. We use two benchmark model setups (lumped and semi-distributed by common approaches) to address the benefits for different time and spatial scales. Moreover, the benefits for calibration effort, model performance in validation periods and process extrapolation are shown.

Spatial and temporal dynamics of shifting cultivation in the middle-Amazonas river: Expansion and intensification.

PubMed

Jakovac, Catarina Conte; Dutrieux, Loïc Paul; Siti, Latifah; Peña-Claros, Marielos; Bongers, Frans

2017-01-01

Shifting cultivation is the main land-use system transforming landscapes in riverine Amazonia. Increased concentration of the human population around villages and increasing market integration during the last decades may be causing agricultural intensification. Studies have shown that agricultural intensification, i.e. higher number of swidden-fallow cycles and shorter fallow periods, reduces crop productivity of swiddens and the regrowth capacity of fallows, undermining the resilience of the shifting cultivation system as a whole. We investigated the temporal and spatial dynamics of shifting cultivation in Brazilian Amazonia to test the hypotheses that (i) agriculture has become more intensive over time, and (ii) patterns of land-use intensity are related to land accessibility and human population density. We applied a breakpoint-detection algorithm to Landsat time-series spanning three decades (1984-2015) and retrieved the temporal dynamics of shifting cultivation fields, which go through alternating phases of crop production (swidden) and secondary forest regrowth (fallow). We found that fallow-period length has decreased from 6.4 to 5.1 years on average, and that expansion over old-growth forest has slowed down over time. Shorter fallow periods and higher frequency of slash and burn cycles are practiced closer to residences and around larger villages. Our results indicate that shifting cultivation in riverine Amazonia has gone through a process of agricultural intensification in the past three decades. The resulting landscape is predominantly covered by young secondary forests (≤ 12 yrs old), and 20% of it have gone through intensive use. Reversing this trend and avoiding the negative consequences of agricultural intensification requires land use planning that accounts for the constraints of land use in riverine areas.

Spatial and temporal dynamics of shifting cultivation in the middle-Amazonas river: Expansion and intensification

PubMed Central

Dutrieux, Loïc Paul; Siti, Latifah; Peña-Claros, Marielos; Bongers, Frans

2017-01-01

Shifting cultivation is the main land-use system transforming landscapes in riverine Amazonia. Increased concentration of the human population around villages and increasing market integration during the last decades may be causing agricultural intensification. Studies have shown that agricultural intensification, i.e. higher number of swidden-fallow cycles and shorter fallow periods, reduces crop productivity of swiddens and the regrowth capacity of fallows, undermining the resilience of the shifting cultivation system as a whole. We investigated the temporal and spatial dynamics of shifting cultivation in Brazilian Amazonia to test the hypotheses that (i) agriculture has become more intensive over time, and (ii) patterns of land-use intensity are related to land accessibility and human population density. We applied a breakpoint-detection algorithm to Landsat time-series spanning three decades (1984–2015) and retrieved the temporal dynamics of shifting cultivation fields, which go through alternating phases of crop production (swidden) and secondary forest regrowth (fallow). We found that fallow-period length has decreased from 6.4 to 5.1 years on average, and that expansion over old-growth forest has slowed down over time. Shorter fallow periods and higher frequency of slash and burn cycles are practiced closer to residences and around larger villages. Our results indicate that shifting cultivation in riverine Amazonia has gone through a process of agricultural intensification in the past three decades. The resulting landscape is predominantly covered by young secondary forests (≤ 12 yrs old), and 20% of it have gone through intensive use. Reversing this trend and avoiding the negative consequences of agricultural intensification requires land use planning that accounts for the constraints of land use in riverine areas. PMID:28727828

The evolution of conditional dispersal and reproductive isolation along environmental gradients

PubMed Central

Payne, Joshua L.; Mazzucco, Rupert; Dieckmann, Ulf

2011-01-01

Dispersal modulates gene flow throughout a population’s spatial range. Gene flow affects adaptation at local spatial scales, and consequently impacts the evolution of reproductive isolation. A recent theoretical investigation has demonstrated that local adaptation along an environmental gradient, facilitated by the evolution of limited dispersal, can lead to parapatric speciation even in the absence of assortative mating. This and other studies assumed unconditional dispersal, so individuals start dispersing without regard to local environmental conditions. However, many species disperse conditionally; their propensity to disperse is contingent upon environmental cues, such as the degree of local crowding or the availability of suitable mates. Here, we use an individual-based model in continuous space to investigate by numerical simulation the relationship between the evolution of threshold-based conditional dispersal and parapatric speciation driven by frequency-dependent competition along environmental gradients. We find that, as with unconditional dispersal, parapatric speciation occurs under a broad range of conditions when reproduction is asexual, and under a more restricted range of conditions when reproduction is sexual. In both the asexual and sexual cases, the evolution of conditional dispersal is strongly influenced by the slope of the environmental gradient: shallow environmental gradients result in low dispersal thresholds and high dispersal distances, while steep environmental gradients result in high dispersal thresholds and low dispersal distances. The latter, however, remain higher than under unconditional dispersal, thus undermining isolation by distance, and hindering speciation in sexual populations. Consequently, the speciation of sexual populations under conditional dispersal is triggered by a steeper gradient than under unconditional dispersal. Enhancing the disruptiveness of frequency-dependent selection, more box-shaped competition kernels dramatically lower the speciation-enabling slope of the environmental gradient. PMID:21194533

The evolution of conditional dispersal and reproductive isolation along environmental gradients.

PubMed

Payne, Joshua L; Mazzucco, Rupert; Dieckmann, Ulf

2011-03-21

Dispersal modulates gene flow throughout a population's spatial range. Gene flow affects adaptation at local spatial scales, and consequently impacts the evolution of reproductive isolation. A recent theoretical investigation has demonstrated that local adaptation along an environmental gradient, facilitated by the evolution of limited dispersal, can lead to parapatric speciation even in the absence of assortative mating. This and other studies assumed unconditional dispersal, so individuals start dispersing without regard to local environmental conditions. However, many species disperse conditionally; their propensity to disperse is contingent upon environmental cues, such as the degree of local crowding or the availability of suitable mates. Here, we use an individual-based model in continuous space to investigate by numerical simulation the relationship between the evolution of threshold-based conditional dispersal and parapatric speciation driven by frequency-dependent competition along environmental gradients. We find that, as with unconditional dispersal, parapatric speciation occurs under a broad range of conditions when reproduction is asexual, and under a more restricted range of conditions when reproduction is sexual. In both the asexual and sexual cases, the evolution of conditional dispersal is strongly influenced by the slope of the environmental gradient: shallow environmental gradients result in low dispersal thresholds and high dispersal distances, while steep environmental gradients result in high dispersal thresholds and low dispersal distances. The latter, however, remain higher than under unconditional dispersal, thus undermining isolation by distance, and hindering speciation in sexual populations. Consequently, the speciation of sexual populations under conditional dispersal is triggered by a steeper gradient than under unconditional dispersal. Enhancing the disruptiveness of frequency-dependent selection, more box-shaped competition kernels dramatically lower the speciation-enabling slope of the environmental gradient. Copyright © 2010 Elsevier Ltd. All rights reserved.

Family Structure, Maternal Dating, and Sexual Debut: Extending the Conceptualization of Instability.

PubMed

Zito, Rena Cornell; De Coster, Stacy

2016-05-01

Family structure influences the risk of early onset of sexual intercourse. This study proposes that the family structures associated with risk-single-mother, step-parent, and cohabiting-influence early sexual debut due to family instability, including shifts in family structure and maternal dating, which can undermine parental control and transmit messages about the acceptability of nonmarital sex. Previous research has not considered maternal dating as a component of family instability, assuming single mothers who date and those who do not date experience comparable levels of family disruption and transmit similar messages about the acceptability of nonmarital sex. Hypotheses are assessed using logistic regression models predicting the odds of early onset of sexual intercourse among 9959 respondents (53 % female, 47 % male) from the National Longitudinal Study of Adolescent to Adult Health. Respondents were ages 12-17 at the first wave of data collection and 18-26 at the third wave, when respondents reported the age at which they first had sexual intercourse. Results show that maternal dating is a source of family instability with repercussions for early sexual debut. Parental control and permissive attitudes towards teenage sex and pregnancy link at-risk family structures and maternal dating to early sexual initiation among females, though these variables do not fully explain family structure and maternal dating effects. Among males, the influence of maternal dating on early sexual debut is fully explained by the learning of permissive sexual attitudes.

A spatial panel ordered-response model with application to the analysis of urban land-use development intensity patterns

NASA Astrophysics Data System (ADS)

Ferdous, Nazneen; Bhat, Chandra R.

2013-01-01

This paper proposes and estimates a spatial panel ordered-response probit model with temporal autoregressive error terms to analyze changes in urban land development intensity levels over time. Such a model structure maintains a close linkage between the land owner's decision (unobserved to the analyst) and the land development intensity level (observed by the analyst) and accommodates spatial interactions between land owners that lead to spatial spillover effects. In addition, the model structure incorporates spatial heterogeneity as well as spatial heteroscedasticity. The resulting model is estimated using a composite marginal likelihood (CML) approach that does not require any simulation machinery and that can be applied to data sets of any size. A simulation exercise indicates that the CML approach recovers the model parameters very well, even in the presence of high spatial and temporal dependence. In addition, the simulation results demonstrate that ignoring spatial dependency and spatial heterogeneity when both are actually present will lead to bias in parameter estimation. A demonstration exercise applies the proposed model to examine urban land development intensity levels using parcel-level data from Austin, Texas.

Self-similarity in nature

NASA Astrophysics Data System (ADS)

Timashev, S. F.

2000-02-01

A general phenomenological approach to the analysis of experimental temporal, spatial and energetic series for extracting truly physical non-model parameters ("passport data") is presented, which may be used to characterize and distinguish the evolution as well as the spatial and energetic structure of any open nonlinear dissipative system. This methodology is based on a postulate concerning the crucial information contained in the sequences of non-regularities of the measured dynamic variable (temporal, spatial, energetic). In accordance with this approach, multi-parametric formulas for dynamic variable power spectra as well as for structural functions of different orders are identical for every spatial-temporal-energetic level of the system under consideration. In effect, this entails the introduction of a new kind of self-similarity in Nature. An algorithm has been developed for obtaining as many "passport data" as are necessary for the characterization of a dynamic system. Applications of this approach in the analysis of various experimental series (temporal, spatial, energetic) demonstrate its potential for defining adequate phenomenological parameters of different dynamic processes and structures.

Spatial networks

NASA Astrophysics Data System (ADS)

Barthélemy, Marc

2011-02-01

Complex systems are very often organized under the form of networks where nodes and edges are embedded in space. Transportation and mobility networks, Internet, mobile phone networks, power grids, social and contact networks, and neural networks, are all examples where space is relevant and where topology alone does not contain all the information. Characterizing and understanding the structure and the evolution of spatial networks is thus crucial for many different fields, ranging from urbanism to epidemiology. An important consequence of space on networks is that there is a cost associated with the length of edges which in turn has dramatic effects on the topological structure of these networks. We will thoroughly explain the current state of our understanding of how the spatial constraints affect the structure and properties of these networks. We will review the most recent empirical observations and the most important models of spatial networks. We will also discuss various processes which take place on these spatial networks, such as phase transitions, random walks, synchronization, navigation, resilience, and disease spread.

Network versus portfolio structure in financial systems

NASA Astrophysics Data System (ADS)

Kobayashi, Teruyoshi

2013-10-01

The question of how to stabilize financial systems has attracted considerable attention since the global financial crisis of 2007-2009. Recently, Beale et al. [Proc. Natl. Acad. Sci. USA 108, 12647 (2011)] demonstrated that higher portfolio diversity among banks would reduce systemic risk by decreasing the risk of simultaneous defaults at the expense of a higher likelihood of individual defaults. In practice, however, a bank default has an externality in that it undermines other banks’ balance sheets. This paper explores how each of these different sources of risk, simultaneity risk and externality, contributes to systemic risk. The results show that the allocation of external assets that minimizes systemic risk varies with the topology of the financial network as long as asset returns have negative correlations. In the model, a well-known centrality measure, PageRank, reflects an appropriately defined “infectiveness” of a bank. An important result is that the most infective bank needs not always to be the safest bank. Under certain circumstances, the most infective node should act as a firewall to prevent large-scale collective defaults. The introduction of a counteractive portfolio structure will significantly reduce systemic risk.

Prediction of dynamic strains on a monopile offshore wind turbine using virtual sensors

NASA Astrophysics Data System (ADS)

Iliopoulos, A. N.; Weijtjens, W.; Van Hemelrijck, D.; Devriendt, C.

2015-07-01

The monitoring of the condition of the offshore wind turbine during its operational states offers the possibility of performing accurate assessments of the remaining life-time as well as supporting maintenance decisions during its entire life. The efficacy of structural monitoring in the case of the offshore wind turbine, though, is undermined by the practical limitations connected to the measurement system in terms of cost, weight and feasibility of sensor mounting (e.g. at muddline level 30m below the water level). This limitation is overcome by reconstructing the full-field response of the structure based on the limited number of measured accelerations and a calibrated Finite Element Model of the system. A modal decomposition and expansion approach is used for reconstructing the responses at all degrees of freedom of the finite element model. The paper will demonstrate the possibility to predict dynamic strains from acceleration measurements based on the aforementioned methodology. These virtual dynamic strains will then be evaluated and validated based on actual strain measurements obtained from a monitoring campaign on an offshore Vestas V90 3 MW wind turbine on a monopile foundation.

Neighborhood and school ethnic structuring and cultural adaptations among Mexican-origin adolescents.

PubMed

White, Rebecca M B; Updegraff, Kimberly A; Umaña-Taylor, Adriana J; Zeiders, Katharine H; Perez-Brena, Norma; Burleson, Elizabeth

2017-03-01

The ethnic and racial structuring of U.S. neighborhoods may have important implications for developmental competencies during adolescence, including the development of heritage and mainstream cultural orientations. In particular, living in highly concentrated Latino neighborhoods during early adolescence-which channels adolescents into related school environments-may promote retention of the ethnic or heritage culture, but it also may constrain adaptation to the mainstream U.S. culture. We tested these hypotheses longitudinally in a sample of 246 Mexican origin adolescents (50.8% girls) and their parents. Data were collected 4 times over 8 years, with adolescents averaging 12.5 (SD = .58) to 19.6 (SD = .66) years of age across the period of the study. Latino ethnic concentration in early adolescents' neighborhoods promoted the retention of Mexican cultural orientations; Latino ethnic concentration in middle schools undermined the development of mainstream U.S cultural orientations. Findings are discussed in terms of integrating cultural-developmental theory with mainstream neighborhood theory to improve understandings of neighborhood and school ethnic concentration effects on adolescent development. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Neighborhood and School Ethnic Structuring and Cultural Adaptations Among Mexican-Origin Adolescents

PubMed Central

White, Rebecca M. B.; Updegraff, Kimberly A.; Umaña-Taylor, Adriana J.; Zeiders, Katharine H.; Perez-Brena, Norma; Burleson, Elizabeth

2016-01-01

The ethnic and racial structuring of U.S. neighborhoods may have important implications for developmental competencies during adolescence, including the development of heritage and mainstream cultural orientations. In particular, living in highly concentrated Latino neighborhoods during early adolescence – which channels adolescents into related school environments – may promote retention of the ethnic or heritage culture, but it also may constrain adaptation to the mainstream U.S. culture. We tested these hypotheses longitudinally in a sample of 246 Mexican origin adolescents (50.8% girls) and their parents. Data were collected four times over eight years, with adolescents averaging 12.5 (SD = .58) to 19.6 (SD = .66) years of age across the period of the study. Latino ethnic concentration in early adolescents' neighborhoods promoted the retention of Mexican cultural orientations; Latino ethnic concentration in middle schools undermined the development of mainstream U.S cultural orientations. Findings are discussed in terms of integrating cultural-developmental theory with mainstream neighborhood theory to improve understandings of neighborhood and school ethnic concentration effects on adolescent development. PMID:27936822

Improving outcomes in cancer diagnosis, prevention and control: barriers, facilitators and the need for health literacy in Ibadan Nigeria.

PubMed

Adedimeji, Adebola A; Lounsbury, David; Popoola, Oluwafemi; Asuzu, Chioma; Lawal, Akinmayowa; Oladoyin, V; Crifase, Cassandra; Agalliu, Ilir; Shankar, Viswanathan; Adebiyi, Akindele

2017-10-01

Cancers constitute a significant public health problem in Nigeria. Breast, cervix and prostate cancers are leading causes of cancer-related deaths. Changing diets, lifestyles, HIV/AIDS and macro-structural factors contribute to cancer morbidity and mortality. Poor health information linking cancer risk to individual behaviors, environmental pollutants and structural barriers undermine prevention/control efforts. Studies suggest increasing health literacy and empowering individuals to take preventive action will improve outcomes and mitigate impact on a weak health system. We obtained qualitative data from 80 men, women, and young adults in 11 focus groups to assess beliefs, risk-perceptions, preventive behaviors and perceptions of barriers and facilitators to cancer control in Ibadan, Nigeria and conducted thematic analysis. Participants demonstrated awareness of cancers and mentioned several risk factors related to individual behaviors and the environment. Nonetheless, myths and misconceptions as well as micro, meso and macro level barriers impede prevention and control efforts. Developing and implementing comprehensive context-relevant health literacy interventions in community settings are urgently needed.Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

HIV epidemiology update and transmission factors: risks and risk contexts--16th International AIDS Conference epidemiology plenary.

PubMed

Beyrer, Chris

2007-04-01

The contexts in which the human immunodeficiency virus (HIV) pandemic is occurring are increasingly diverse. Individual-level risks for HIV infection are at the core of these epidemics and are powerfully impacted by social, structural, and population-level risks and protections. The emerging epidemics among injection drug users across Eurasia are largely the result of needle sharing, but the drivers of disease spread include increases in opiate availability, limited HIV infection prevention and programs for drug users, and undermining policy environments. An emerging epidemic of HIV infection among men who have sex with men in developing countries is primarily spread through unprotected anal intercourse but is also driven by limited HIV infection prevention services, social stigma, and the lack of human rights protection. The epidemic in southern Africa, which is spreading largely through heterosexual exposure, is driven by high rates of labor migration, concurrent sexual partnerships, gender inequalities, and the limited availability of male condoms. We need to do much more to control HIV infection, and social and structural risks are crucial intervention targets.

Implications of antisocial parents.

PubMed

Torry, Zachary D; Billick, Stephen B

2011-12-01

Antisocial behavior is a socially maladaptive and harmful trait to possess. This can be especially injurious for a child who is raised by a parent with this personality structure. The pathology of antisocial behavior implies traits such as deceitfulness, irresponsibility, unreliability, and an incapability to feel guilt, remorse, or even love. This is damaging to a child's emotional, cognitive, and social development. Parents with this personality makeup can leave a child traumatized, empty, and incapable of forming meaningful personal relationships. Both genetic and environmental factors influence the development of antisocial behavior. Moreover, the child with a genetic predisposition to antisocial behavior who is raised with a parental style that triggers the genetic liability is at high risk for developing the same personality structure. Antisocial individuals are impulsive, irritable, and often have no concerns over their purported responsibilities. As a parent, this can lead to erratic discipline, neglectful parenting, and can undermine effective care giving. This paper will focus on the implications of parents with antisocial behavior and the impact that this behavior has on attachment as well as on the development of antisocial traits in children.

Structural Vulnerability: Operationalizing the Concept to Address Health Disparities in Clinical Care.

PubMed

Bourgois, Philippe; Holmes, Seth M; Sue, Kim; Quesada, James

2017-03-01

The authors propose reinvigorating and extending the traditional social history beyond its narrow range of risk behaviors to enable clinicians to address negative health outcomes imposed by social determinants of health. In this Perspective, they outline a novel, practical medical vulnerability assessment questionnaire that operationalizes for clinical practice the social science concept of "structural vulnerability." A structural vulnerability assessment tool designed to highlight the pathways through which specific local hierarchies and broader sets of power relationships exacerbate individual patients' health problems is presented to help clinicians identify patients likely to benefit from additional multidisciplinary health and social services. To illustrate how the tool could be implemented in time- and resource-limited settings (e.g., emergency department), the authors contrast two cases of structurally vulnerable patients with differing outcomes. Operationalizing structural vulnerability in clinical practice and introducing it in medical education can help health care practitioners think more clearly, critically, and practically about the ways social structures make people sick. Use of the assessment tool could promote "structural competency," a potential new medical education priority, to improve understanding of how social conditions and practical logistics undermine the capacities of patients to access health care, adhere to treatment, and modify lifestyles successfully. Adoption of a structural vulnerability framework in health care could also justify the mobilization of resources inside and outside clinical settings to improve a patient's immediate access to care and long-term health outcomes. Ultimately, the concept may orient health care providers toward policy leadership to reduce health disparities and foster health equity.

Structural Vulnerability: Operationalizing the Concept to Address Health Disparities in Clinical Care

PubMed Central

Bourgois, Philippe; Holmes, Seth M.; Sue, Kim; Quesada, James

2016-01-01

The authors propose reinvigorating and extending the traditional social history beyond its narrow range of risk behaviors to enable clinicians to address negative health outcomes imposed by social determinants of health. In this Perspective, they outline a novel, practical medical vulnerability assessment questionnaire that operationalizes for clinical practice the social science concept of “structural vulnerability.” A Structural Vulnerability Assessment Tool designed to highlight the pathways through which specific local hierarchies and broader sets of power relationships exacerbate individual patients’ health problems is presented to help clinicians identify patients likely to benefit from additional multi-disciplinary health and social services. To illustrate how the tool could be implemented in time- and resource-limited settings (e.g., emergency department), the authors contrast two cases of structurally vulnerable patients with differing outcomes. Operationalizing structural vulnerability in clinical practice and introducing it in medical education can help health care practitioners think more clearly, critically, and practically about the ways social structures make people sick. Use of the assessment tool could promote “structural competency,” a potential new medical education priority, to improve understanding of how social conditions and practical logistics undermine the capacities of patients to access health care, adhere to treatment, and modify lifestyles successfully. Adoption of a structural vulnerability framework in health care could also justify the mobilization of resources inside and outside clinical settings to improve a patient's immediate access to care and long-term health outcomes. Ultimately, the concept may orient health care providers toward policy leadership to reduce health disparities and foster health equity. PMID:27415443

Spatial structure favors cooperative behavior in the snowdrift game with multiple interactive dynamics

NASA Astrophysics Data System (ADS)

Su, Qi; Li, Aming; Wang, Long

2017-02-01

Spatial reciprocity is generally regarded as a positive rule facilitating the evolution of cooperation. However, a few recent studies show that, in the snowdrift game, spatial structure still could be detrimental to cooperation. Here we propose a model of multiple interactive dynamics, where each individual can cooperate and defect simultaneously against different neighbors. We realize individuals' multiple interactions simply by endowing them with strategies relevant to probabilities, and every one decides to cooperate or defect with a probability. With multiple interactive dynamics, the cooperation level in square lattices is higher than that in the well-mixed case for a wide range of cost-to-benefit ratio r, implying that spatial structure favors cooperative behavior in the snowdrift game. Moreover, in square lattices, the most favorable strategy follows a simple relation of r, which confers theoretically the average evolutionary frequency of cooperative behavior. We further extend our study to various homogeneous and heterogeneous networks, which demonstrates the robustness of our results. Here multiple interactive dynamics stabilizes the positive role of spatial structure on the evolution of cooperation and individuals' distinct reactions to different neighbors can be a new line in understanding the emergence of cooperation.

A passive mutualistic interaction promotes the evolution of spatial structure within microbial populations.

PubMed

Marchal, Marie; Goldschmidt, Felix; Derksen-Müller, Selina N; Panke, Sven; Ackermann, Martin; Johnson, David R

2017-04-24

While mutualistic interactions between different genotypes are pervasive in nature, their evolutionary origin is not clear. The dilemma is that, for mutualistic interactions to emerge and persist, an investment into the partner genotype must pay off: individuals of a first genotype that invest resources to promote the growth of a second genotype must receive a benefit that is not equally accessible to individuals that do not invest. One way for exclusive benefits to emerge is through spatial structure (i.e., physical barriers to the movement of individuals and resources). Here we propose that organisms can evolve their own spatial structure based on physical attachment between individuals, and we hypothesize that attachment evolves when spatial proximity to members of another species is advantageous. We tested this hypothesis using experimental evolution with combinations of E. coli strains that depend on each other to grow. We found that attachment between cells repeatedly evolved within 8 weeks of evolution and observed that many different types of mutations potentially contributed to increased attachment. We postulate a general principle by which passive beneficial interactions between organisms select for attachment, and attachment then provides spatial structure that could be conducive for the evolution of active mutualistic interactions.

The Importance of Temporal and Spatial Vegetation Structure Information in Biotope Mapping Schemes: A Case Study in Helsingborg, Sweden

NASA Astrophysics Data System (ADS)

Gao, Tian; Qiu, Ling; Hammer, Mårten; Gunnarsson, Allan

2012-02-01

Temporal and spatial vegetation structure has impact on biodiversity qualities. Yet, current schemes of biotope mapping do only to a limited extend incorporate these factors in the mapping. The purpose of this study is to evaluate the application of a modified biotope mapping scheme that includes temporal and spatial vegetation structure. A refined scheme was developed based on a biotope classification, and applied to a green structure system in Helsingborg city in southern Sweden. It includes four parameters of vegetation structure: continuity of forest cover, age of dominant trees, horizontal structure, and vertical structure. The major green structure sites were determined by interpretation of panchromatic aerial photographs assisted with a field survey. A set of biotope maps was constructed on the basis of each level of modified classification. An evaluation of the scheme included two aspects in particular: comparison of species richness between long-continuity and short-continuity forests based on identification of woodland continuity using ancient woodland indicators (AWI) species and related historical documents, and spatial distribution of animals in the green space in relation to vegetation structure. The results indicate that (1) the relationship between forest continuity: according to verification of historical documents, the richness of AWI species was higher in long-continuity forests; Simpson's diversity was significantly different between long- and short-continuity forests; the total species richness and Shannon's diversity were much higher in long-continuity forests shown a very significant difference. (2) The spatial vegetation structure and age of stands influence the richness and abundance of the avian fauna and rabbits, and distance to the nearest tree and shrub was a strong determinant of presence for these animal groups. It is concluded that continuity of forest cover, age of dominant trees, horizontal and vertical structures of vegetation should now be included in urban biotope classifications.

Exploring new topography-based subgrid spatial structures for improving land surface modeling

DOE PAGES

Tesfa, Teklu K.; Leung, Lai-Yung Ruby

2017-02-22

Topography plays an important role in land surface processes through its influence on atmospheric forcing, soil and vegetation properties, and river network topology and drainage area. Land surface models with a spatial structure that captures spatial heterogeneity, which is directly affected by topography, may improve the representation of land surface processes. Previous studies found that land surface modeling, using subbasins instead of structured grids as computational units, improves the scalability of simulated runoff and streamflow processes. In this study, new land surface spatial structures are explored by further dividing subbasins into subgrid structures based on topographic properties, including surface elevation,more » slope and aspect. Two methods (local and global) of watershed discretization are applied to derive two types of subgrid structures (geo-located and non-geo-located) over the topographically diverse Columbia River basin in the northwestern United States. In the global method, a fixed elevation classification scheme is used to discretize subbasins. The local method utilizes concepts of hypsometric analysis to discretize each subbasin, using different elevation ranges that also naturally account for slope variations. The relative merits of the two methods and subgrid structures are investigated for their ability to capture topographic heterogeneity and the implications of this on representations of atmospheric forcing and land cover spatial patterns. Results showed that the local method reduces the standard deviation (SD) of subgrid surface elevation in the study domain by 17 to 19 % compared to the global method, highlighting the relative advantages of the local method for capturing subgrid topographic variations. The comparison between the two types of subgrid structures showed that the non-geo-located subgrid structures are more consistent across different area threshold values than the geo-located subgrid structures. Altogether the local method and non-geo-located subgrid structures effectively and robustly capture topographic, climatic and vegetation variability, which is important for land surface modeling.« less

Exploring new topography-based subgrid spatial structures for improving land surface modeling

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

Tesfa, Teklu K.; Leung, Lai-Yung Ruby

Topography plays an important role in land surface processes through its influence on atmospheric forcing, soil and vegetation properties, and river network topology and drainage area. Land surface models with a spatial structure that captures spatial heterogeneity, which is directly affected by topography, may improve the representation of land surface processes. Previous studies found that land surface modeling, using subbasins instead of structured grids as computational units, improves the scalability of simulated runoff and streamflow processes. In this study, new land surface spatial structures are explored by further dividing subbasins into subgrid structures based on topographic properties, including surface elevation,more » slope and aspect. Two methods (local and global) of watershed discretization are applied to derive two types of subgrid structures (geo-located and non-geo-located) over the topographically diverse Columbia River basin in the northwestern United States. In the global method, a fixed elevation classification scheme is used to discretize subbasins. The local method utilizes concepts of hypsometric analysis to discretize each subbasin, using different elevation ranges that also naturally account for slope variations. The relative merits of the two methods and subgrid structures are investigated for their ability to capture topographic heterogeneity and the implications of this on representations of atmospheric forcing and land cover spatial patterns. Results showed that the local method reduces the standard deviation (SD) of subgrid surface elevation in the study domain by 17 to 19 % compared to the global method, highlighting the relative advantages of the local method for capturing subgrid topographic variations. The comparison between the two types of subgrid structures showed that the non-geo-located subgrid structures are more consistent across different area threshold values than the geo-located subgrid structures. Altogether the local method and non-geo-located subgrid structures effectively and robustly capture topographic, climatic and vegetation variability, which is important for land surface modeling.« less

A hybrid structure for the storage and manipulation of very large spatial data sets

USGS Publications Warehouse

Peuquet, Donna J.

1982-01-01

The map data input and output problem for geographic information systems is rapidly diminishing with the increasing availability of mass digitizing, direct spatial data capture and graphics hardware based on raster technology. Although a large number of efficient raster-based algorithms exist for performing a wide variety of common tasks on these data, there are a number of procedures which are more efficiently performed in vector mode or for which raster mode equivalents of current vector-based techniques have not yet been developed. This paper presents a hybrid spatial data structure, named the ?vaster' structure, which can utilize the advantages of both raster and vector structures while potentially eliminating, or greatly reducing, the need for raster-to-vector and vector-to-raster conversion. Other advantages of the vaster structure are also discussed.

Integrative Structure Determination of Protein Assemblies by Satisfaction of Spatial Restraints

NASA Astrophysics Data System (ADS)

Alber, Frank; Chait, Brian T.; Rout, Michael P.; Sali, Andrej

To understand the cell, we need to determine the structures of macromolecular assemblies, many of which consist of tens to hundreds of components. A great variety of experimental data can be used to characterize the assemblies at several levels of resolution, from atomic structures to component configurations. To maximize completeness, resolution, accuracy, precision and efficiency of the structure determination, a computational approach is needed that can use spatial information from a variety of experimental methods. We propose such an approach, defined by its three main components: a hierarchical representation of the assembly, a scoring function consisting of spatial restraints derived from experimental data, and an optimization method that generates structures consistent with the data. We illustrate the approach by determining the configuration of the 456 proteins in the nuclear pore complex from Baker's yeast.

Structural variations in prefrontal cortex mediate the relationship between early childhood stress and spatial working memory

PubMed Central

Hanson, Jamie L.; Chung, Moo K.; Avants, Brian B.; Rudolph, Karen D.; Shirtcliff, Elizabeth A.; Gee, James C.; Davidson, Richard J.; Pollak, Seth D.

2012-01-01

A large corpus of research indicates exposure to stress impairs cognitive abilities, specifically executive functioning dependent on the prefrontal cortex (PFC). We collected structural MRI scans (n=61), well-validated assessments of executive functioning, and detailed interviews assessing stress exposure in humans, to examine whether cumulative life stress affected brain morphometry and one type of executive functioning, spatial working memory, during adolescence—a critical time of brain development and reorganization. Analysis of variations in brain structure revealed that cumulative life stress and spatial working memory were related to smaller volumes in the PFC, specifically prefrontal gray and white matter between the anterior cingulate and the frontal poles. Mediation analyses revealed that individual differences in prefrontal volumes accounted for the association between cumulative life stress and spatial working memory. These results suggest that structural changes in the PFC may serve as a mediating mechanism through which greater cumulative life stress engenders decrements in cognitive functioning. PMID:22674267

THE EVOLUTION OF RESTRAINT IN BACTERIAL BIOFILMS UNDER NONTRANSITIVE COMPETITION

PubMed Central

Prado, Federico; Kerr, Benjamin

2009-01-01

Theoretical and empirical evidence indicates that competing species can coexist if dispersal, migration, and competitive interactions occur over relatively small spatial scales. In particular, spatial structure appears to be critical to certain communities with nontransitive competition. A typical nontransitive system involves three competing species that satisfy a relationship similar to the children’s game of rock–paper–scissors. Although the ecological dynamics of nontransitive systems in spatially structured communities have received some attention, fewer studies have incorporated evolutionary change. Here we investigate evolution within toxic bacterial biofilms using an agent-based simulation that represents a nontransitive community containing three populations of Escherichia coli. In structured, nontransitive communities, strains evolve that do not maximize their competitive ability: They do not reduce their probability of death to a minimum or increase their toxicity to a maximum. That is, types evolve that exercise restraint. We show that nontransitivity and spatial structure (in the form of localized interactions) are both necessary for the evolution of restraint in these biofilms. PMID:18039324

The evolution of restraint in bacterial biofilms under nontransitive competition.

PubMed

Prado, Federico; Kerr, Benjamin

2008-03-01

Theoretical and empirical evidence indicates that competing species can coexist if dispersal, migration, and competitive interactions occur over relatively small spatial scales. In particular, spatial structure appears to be critical to certain communities with nontransitive competition. A typical nontransitive system involves three competing species that satisfy a relationship similar to the children's game of rock-paper-scissors. Although the ecological dynamics of nontransitive systems in spatially structured communities have received some attention, fewer studies have incorporated evolutionary change. Here we investigate evolution within toxic bacterial biofilms using an agent-based simulation that represents a nontransitive community containing three populations of Escherichia coli. In structured, nontransitive communities, strains evolve that do not maximize their competitive ability: They do not reduce their probability of death to a minimum or increase their toxicity to a maximum. That is, types evolve that exercise restraint. We show that nontransitivity and spatial structure (in the form of localized interactions) are both necessary for the evolution of restraint in these biofilms.

The Detection and Characterization of Urbanization, Industrialization, and Longwall Mining Impacts on Forest Ecosystems Through the Use of GiS and Remote Sensing Techniques

NASA Astrophysics Data System (ADS)

Pfeil-McCullough, Erin Kathleen

Urbanization has far reaching and significant effects on forest ecosystems, directly through urban development and indirectly through supportive processes such as coal mining and agriculture. Urban processes modify the landscape leading to altered hillslope hydrology, increased disturbance, and the introduction of non-native forest pathogens. This dissertation addresses several challenges in our ability to detect these urbanization impacts on forests via geospatial analyses. The role of forests in urban hydrological processes has been extensively studied, but the impacts of urbanized hydrology on forests remain poorly examined. This dissertation documented impacts to hydrology and forests at variety of temporal and spatial scales: 1) A geospatial comparison of the historic and contemporary forests of Allegheny County, Pennsylvania revealed substantial shifts in tree species, but less change in the species soil moisture preference. These results document additional evidence that increased heterogeneity in urban soil moisture alters forest structure. 2) To examine soil moisture changes, impacts of longwall mine subsidence were assessed by using a Landsat based canopy moisture index and hot spot analysis tools at the forest patch scale. Declines in forest canopy moisture were detected over longwall mines as mining progressed through time, and results contradicted assumptions that the hydrological impacts overlying LMS recover within 4-5 years following subsidence of undermined land. 3) Utilizing a landslide susceptibility model (SINMAP), increases in landslide susceptibility were predicted in Pittsburgh, PA based on several scenarios of ash tree loss to the emerald ash borer (EAB), a bark beetle that rapidly kills ash trees. This model provides a tool to predict changes in landslide susceptibility following tree loss, increasing the understanding of urban forest function and its role in slope stability. Detecting how urbanized hydrology impacts forest health, function, and development is fundamental to sustaining the services forests provide. Results from this dissertation will ultimately allow improvements in the management and protection of both trees and water resources in urban systems and beyond.

Hydromorphological adjustments and re-adjustments of low energy rivers in a sub-urban catchment following historical engineering and recent urbanization

NASA Astrophysics Data System (ADS)

Jugie, Marion; Gob, Frédéric; Slawson, Deborah; Le-Coeur, Charles

2014-05-01

The EU Water Framework Directive (WFD, October 2000) mandated that the Member States of the European Union achieve the general objective of protection of aquatic ecology by 2015. European rivers and streams have to attain "good ecological status" through the preservation and restoration of aquatic environments. Member will have to ensure environmental continuity through "the adequate distribution of fish species and transport of sediments". In France, more than 61,000 transverse structures - mill dams, weirs, diversion gates - have been identified on rivers as being obstacles to ecological and sedimentary continuity. Because of their historical occupation by societies, rivers flowing in the Paris area have long been anthropized and artificialized. River courses, channel shape, sediment transport and hydrological regime modifications have tremendously transformed the hydrosystems surrounding the city of Paris. The Merantaise's catchment is one of this low energy river watershed, near Paris, that have been modified by historical engineering, especially during medieval-modern times and by the building of the Versailles Castle (XVIIth century). The hydraulic infrastructures are still there and impact the hydromorphogical conditions of the river (incision, lateral erosion, …). In addition to these ancient pressures a rapid and massive urbanization of the suburban areas has applied a new type of constraint to the hydrosystems in recent decades. This undermines the balance that was established following ancient engineering and disturbs the current functioning of the valley. These new types of land occupation have significantly altered the ecological circumstances and transformed the hydrological responses of rivers. In this study, we therefore seek to understand these processes of successive adjustments (ancient and recent) of a small river from the urban margins of the Orge watershed (to the south of Paris). We use a multi-scalar spatial and temporal approach to reconstruct the hydromorphological circumstances ancient and current, by hydrological chronicles and archives documentation.

Distance indicators based on the luminosity-profile shapes of early-type galaxies-a reply

NASA Astrophysics Data System (ADS)

Young, Christopher Ke-Shih; Currie, Malcolm J.

1998-05-01

In a recent paper, Binggeli & Jerjen (1998) question the value of the extragalactic distance indicators presented by Young & Currie (1994 & 1995) and state that they have refuted `the claim that the Virgo dEs [dwarf-elliptical galaxies]...are distributed in a prolate structure stretching from 8 to 20 Mpc distance (Young & Currie 1995).' even though no such claim was ever made. In this paper, we examine Binggeli & Jerjen's claims that intrinsic scatter rather than spatial depth must be the main cause of the large scatters observed in the relevant scaling relationships for Virgo galaxies. We investigate the accuracy of Binggeli & Jerjen's photometric parameters and find that while their profile curvature and scalelength measurements are probably useful, their total magnitude and central surface-brightness measurements are not useful for the purpose of investigating scaling laws because they suffer from serious systematic and random errors. We also investigate Binggeli & Jerjen's criticisms of our (1995) analysis. We demonstrate that their test for strong mutual dependence between distance estimates based on the two different scaling laws is invalid because of its prior assumption of negligible cluster depth. We further demonstrate that the [relative] distance estimates on which their kinematical arguments are based cannot be meaningful, not only because of the seriousness of the photometric errors, but also because they are undermined by the prior assumption that depth effects can again be neglected. Interestingly, we also find that Binggeli & Jerjen's own dataset does itself contain evidence for large depth. Using the observed correlation between scale-length and profile-curvature, (the only correlation that can be investigated meaningfully using their dataset), we find that the frequency distribution of residuals with respect to the best fitting curve deviates significantly from that expected from a uni-modal Gaussian distribution. Clearly, if as Binggeli & Jerjen claim, the very large scatter observed in this scaling relationship for Virgo galaxies (which is not observed for Fornax or Local Group ones) were intrinsic, one would expect a uni-modal Gaussian distribution.

Flexible spatial perspective-taking: conversational partners weigh multiple cues in collaborative tasks.

PubMed

Galati, Alexia; Avraamides, Marios N

2013-01-01

Research on spatial perspective-taking often focuses on the cognitive processes of isolated individuals as they adopt or maintain imagined perspectives. Collaborative studies of spatial perspective-taking typically examine speakers' linguistic choices, while overlooking their underlying processes and representations. We review evidence from two collaborative experiments that examine the contribution of social and representational cues to spatial perspective choices in both language and the organization of spatial memory. Across experiments, speakers organized their memory representations according to the convergence of various cues. When layouts were randomly configured and did not afford intrinsic cues, speakers encoded their partner's viewpoint in memory, if available, but did not use it as an organizing direction. On the other hand, when the layout afforded an intrinsic structure, speakers organized their spatial memories according to the person-centered perspective reinforced by the layout's structure. Similarly, in descriptions, speakers considered multiple cues whether available a priori or at the interaction. They used partner-centered expressions more frequently (e.g., "to your right") when the partner's viewpoint was misaligned by a small offset or coincided with the layout's structure. Conversely, they used egocentric expressions more frequently when their own viewpoint coincided with the intrinsic structure or when the partner was misaligned by a computationally difficult, oblique offset. Based on these findings we advocate for a framework for flexible perspective-taking: people weigh multiple cues (including social ones) to make attributions about the relative difficulty of perspective-taking for each partner, and adapt behavior to minimize their collective effort. This framework is not specialized for spatial reasoning but instead emerges from the same principles and memory-depended processes that govern perspective-taking in non-spatial tasks.

Flexible spatial perspective-taking: conversational partners weigh multiple cues in collaborative tasks

PubMed Central

Galati, Alexia; Avraamides, Marios N.

2013-01-01

Research on spatial perspective-taking often focuses on the cognitive processes of isolated individuals as they adopt or maintain imagined perspectives. Collaborative studies of spatial perspective-taking typically examine speakers' linguistic choices, while overlooking their underlying processes and representations. We review evidence from two collaborative experiments that examine the contribution of social and representational cues to spatial perspective choices in both language and the organization of spatial memory. Across experiments, speakers organized their memory representations according to the convergence of various cues. When layouts were randomly configured and did not afford intrinsic cues, speakers encoded their partner's viewpoint in memory, if available, but did not use it as an organizing direction. On the other hand, when the layout afforded an intrinsic structure, speakers organized their spatial memories according to the person-centered perspective reinforced by the layout's structure. Similarly, in descriptions, speakers considered multiple cues whether available a priori or at the interaction. They used partner-centered expressions more frequently (e.g., “to your right”) when the partner's viewpoint was misaligned by a small offset or coincided with the layout's structure. Conversely, they used egocentric expressions more frequently when their own viewpoint coincided with the intrinsic structure or when the partner was misaligned by a computationally difficult, oblique offset. Based on these findings we advocate for a framework for flexible perspective-taking: people weigh multiple cues (including social ones) to make attributions about the relative difficulty of perspective-taking for each partner, and adapt behavior to minimize their collective effort. This framework is not specialized for spatial reasoning but instead emerges from the same principles and memory-depended processes that govern perspective-taking in non-spatial tasks. PMID:24133432

Classification of Farmland Landscape Structure in Multiple Scales

NASA Astrophysics Data System (ADS)

Jiang, P.; Cheng, Q.; Li, M.

2017-12-01

Farmland is one of the basic terrestrial resources that support the development and survival of human beings and thus plays a crucial role in the national security of every country. Pattern change is the intuitively spatial representation of the scale and quality variation of farmland. Through the characteristic development of spatial shapes as well as through changes in system structures, functions and so on, farmland landscape patterns may indicate the landscape health level. Currently, it is still difficult to perform positioning analyses of landscape pattern changes that reflect the landscape structure variations of farmland with an index model. Depending on a number of spatial properties such as locations and adjacency relations, distance decay, fringe effect, and on the model of patch-corridor-matrix that is applied, this study defines a type system of farmland landscape structure on the national, provincial, and city levels. According to such a definition, the classification model of farmland landscape-structure type at the pixel scale is developed and validated based on mathematical-morphology concepts and on spatial-analysis methods. Then, the laws that govern farmland landscape-pattern change in multiple scales are analyzed from the perspectives of spatial heterogeneity, spatio-temporal evolution, and function transformation. The result shows that the classification model of farmland landscape-structure type can reflect farmland landscape-pattern change and its effects on farmland production function. Moreover, farmland landscape change in different scales displayed significant disparity in zonality, both within specific regions and in urban-rural areas.

Exploring the Spatial and Temporal Organization of a Cell’s Proteome

PubMed Central

Beck, Martin; Topf, Maya; Frazier, Zachary; Tjong, Harianto; Xu, Min; Zhang, Shihua; Alber, Frank

2013-01-01

To increase our current understanding of cellular processes, such as cell signaling and division, knowledge is needed about the spatial and temporal organization of the proteome at different organizational levels. These levels cover a wide range of length and time scales: from the atomic structures of macromolecules for inferring their molecular function, to the quantitative description of their abundance, and distribution in the cell. Emerging new experimental technologies are greatly increasing the availability of such spatial information on the molecular organization in living cells. This review addresses three fields that have significantly contributed to our understanding of the proteome’s spatial and temporal organization: first, methods for the structure determination of individual macromolecular assemblies, specifically the fitting of atomic structures into density maps generated from electron microscopy techniques; second, research that visualizes the spatial distributions of these complexes within the cellular context using cryo electron tomography techniques combined with computational image processing; and third, methods for the spatial modeling of the dynamic organization of the proteome, specifically those methods for simulating reaction and diffusion of proteins and complexes in crowded intracellular fluids. The long-term goal is to integrate the varied data about a proteome’s organization into a spatially explicit, predictive model of cellular processes. PMID:21094684

Spatially structured superinfection and the evolution of disease virulence.

PubMed

Caraco, Thomas; Glavanakov, Stephan; Li, Shengua; Maniatty, William; Szymanski, Boleslaw K

2006-06-01

When pathogen strains differing in virulence compete for hosts, spatial structuring of disease transmission can govern both evolved levels of virulence and patterns in strain coexistence. We develop a spatially detailed model of superinfection, a form of contest competition between pathogen strains; the probability of superinfection depends explicitly on the difference in levels of virulence. We apply methods of adaptive dynamics to address the interplay of spatial dynamics and evolution. The mean-field approximation predicts evolution to criticality; any small increase in virulence capable of dynamical persistence is favored. Both pair approximation and simulation of the detailed model indicate that spatial structure constrains disease virulence. Increased spatial clustering reduces the maximal virulence capable of single-strain persistence and, more importantly, reduces the convergent-stable virulence level under strain competition. The spatially detailed model predicts that increasing the probability of superinfection, for given difference in virulence, increases the likelihood of between-strain coexistence. When strains differing in virulence can coexist ecologically, our results may suggest policies for managing diseases with localized transmission. Comparing equilibrium densities from the pair approximation, we find that introducing a more virulent strain into a host population infected by a less virulent strain can sometimes reduce total host mortality and increase global host density.

Influence of landscape structure on reef fish assemblages

USGS Publications Warehouse

Grober-Dunsmore, R.; Frazer, T.K.; Beets, J.P.; Lindberg, W.J.; Zwick, P.; Funicelli, N.A.

2008-01-01

Management of tropical marine environments calls for interdisciplinary studies and innovative methodologies that consider processes occurring over broad spatial scales. We investigated relationships between landscape structure and reef fish assemblage structure in the US Virgin Islands. Measures of landscape structure were transformed into a reduced set of composite indices using principal component analyses (PCA) to synthesize data on the spatial patterning of the landscape structure of the study reefs. However, composite indices (e.g., habitat diversity) were not particularly informative for predicting reef fish assemblage structure. Rather, relationships were interpreted more easily when functional groups of fishes were related to individual habitat features. In particular, multiple reef fish parameters were strongly associated with reef context. Fishes responded to benthic habitat structure at multiple spatial scales, with various groups of fishes each correlated to a unique suite of variables. Accordingly, future experiments should be designed to test functional relationships based on the ecology of the organisms of interest. Our study demonstrates that landscape-scale habitat features influence reef fish communities, illustrating promise in applying a landscape ecology approach to better understand factors that structure coral reef ecosystems. Furthermore, our findings may prove useful in design of spatially-based conservation approaches such as marine protected areas (MPAs), because landscape-scale metrics may serve as proxies for areas with high species diversity and abundance within the coral reef landscape. ?? 2007 Springer Science+Business Media B.V.

Spatial structure in the diet of imperial eagles Aquila heliaca in Kazakhstan

USGS Publications Warehouse

Katzner, T.E.; Bragin, E.A.; Knick, S.T.; Smith, A.T.

2006-01-01

We evaluated the relationship between spatial variability in prey and food habits of eastern imperial eagles Aquila heliaca at a 90,000 ha national nature reserve in north-central Kazakhstan. Eagle diet varied greatly within the population and the spatial structure of eagle diet within the population varied according to the scale of measurement. Patterns in dietary response were inconsistent with expectations if either ontogenetic imprinting or competition determined diet choice, but they met expectations if functional response determined diet. Eagles nesting near a high-density prey resource used that resource almost exclusively. In contrast, in locations with no single high-density prey species, eagles' diet was more diverse. Our results demonstrate that spatial structuring of diet of vertebrate predators can provide important insight into the mechanisms that drive dietary decisions. ?? OIKOS.

78 FR 52011 - Highly Migratory Species; 2006 Consolidated Atlantic Highly Migratory Species Fishery Management...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-21

... fishery; a new open access permit would undermine full-time commercial fishermen by allowing quasi... quota. Experimental longline fishing conducted there has proven the viability of swordfish landings with...

The implementation, interpretation, and justification of likelihoods in cosmology

NASA Astrophysics Data System (ADS)

McCoy, C. D.

2018-05-01

I discuss the formal implementation, interpretation, and justification of likelihood attributions in cosmology. I show that likelihood arguments in cosmology suffer from significant conceptual and formal problems that undermine their applicability in this context.

Factors that influence women's health in Tanzania.

PubMed

Lugina, H I

1994-01-01

A descriptive account of factors that influence women's health in Tanzania is given. The social and cultural processes that enhance or undermine women's health are emphasized. Recommendations for changes to improve women's health are made.

The "Iconoclast," a superb instrument for undermining.

PubMed

Luikart, R

1980-04-01

The "Iconoclast" was designed to separate with ease the dermis from underlying fascia or periosteum. It dissects bluntly and thus reduces need for sharp cutting and snipping, and minimizes damage to blood vessels and nerves.

78 FR 26425 - Sentencing Guidelines for United States Courts

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-06

... tax system and the legal system as a whole. Therefore, to use them to reduce the tax loss would... undermine the public's confidence in the medical regulatory and distribution system. The Commission also...

78 FR 21811 - National Equal Pay Day, 2013

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-11

... make what men did in the previous one. Wage inequality undermines the promise of fairness and... a long way toward ensuring everyone gets a fair shot at opportunity, no matter who you are or where...

Regional-scale drivers of marine nematode distribution in Southern Ocean continental shelf sediments

NASA Astrophysics Data System (ADS)

Hauquier, Freija; Verleyen, Elie; Tytgat, Bjorn; Vanreusel, Ann

2018-07-01

Many marine meiofauna taxa seem to possess cosmopolitan species distributions, despite their endobenthic lifestyle and restricted long-distance dispersal capacities. In light of this paradox we used a metacommunity framework to study spatial turnover in free-living nematode distribution and assess the importance of local environmental conditions in explaining differences between communities in surface and subsurface sediments of the Southern Ocean continental shelf. We analysed nematode community structure in two sediment layers (0-3 cm and 3-5 cm) of locations maximum 2400 km apart. We first focused on a subset of locations to evaluate whether the genus level is sufficiently taxonomically fine-grained to study large-scale patterns in nematode community structure. We subsequently used redundancy and variation partitioning analyses to quantify the unique and combined effects of local environmental conditions and spatial descriptors on genus-level community composition. Macroecological patterns in community structure were highly congruent at the genus and species level. Nematode community composition was highly divergent between both depth strata, likely as a result of local abiotic conditions. Variation in community structure between the different regions largely stemmed from turnover (i.e. genus/species replacement) rather than nestedness (i.e. genus/species loss). The level of turnover among communities increased with geographic distance and was more pronounced in subsurface layers compared to surface sediments. Variation partitioning analysis revealed that both environmental and spatial predictors significantly explained variation in community structure. Moreover, the shared fraction of both sets of variables was high, which suggested a substantial amount of spatially structured environmental variation. Additionally, the effect of space independent of environment was much higher than the effect of environment independent of space, which shows the importance of including spatial descriptors in meiofauna and nematode community ecology. Large-scale assessment of free-living nematode diversity and abundance in the Southern Ocean shelf zone revealed strong horizontal and vertical spatial structuring in response to local environmental conditions, in combination with (most likely) dispersal limitation.

Emergent spatial synaptic structure from diffusive plasticity.

PubMed

Sweeney, Yann; Clopath, Claudia

2017-04-01

Some neurotransmitters can diffuse freely across cell membranes, influencing neighbouring neurons regardless of their synaptic coupling. This provides a means of neural communication, alternative to synaptic transmission, which can influence the way in which neural networks process information. Here, we ask whether diffusive neurotransmission can also influence the structure of synaptic connectivity in a network undergoing plasticity. We propose a form of Hebbian synaptic plasticity which is mediated by a diffusive neurotransmitter. Whenever a synapse is modified at an individual neuron through our proposed mechanism, similar but smaller modifications occur in synapses connecting to neighbouring neurons. The effects of this diffusive plasticity are explored in networks of rate-based neurons. This leads to the emergence of spatial structure in the synaptic connectivity of the network. We show that this spatial structure can coexist with other forms of structure in the synaptic connectivity, such as with groups of strongly interconnected neurons that form in response to correlated external drive. Finally, we explore diffusive plasticity in a simple feedforward network model of receptive field development. We show that, as widely observed across sensory cortex, the preferred stimulus identity of neurons in our network become spatially correlated due to diffusion. Our proposed mechanism of diffusive plasticity provides an efficient mechanism for generating these spatial correlations in stimulus preference which can flexibly interact with other forms of synaptic organisation. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

An evaluation of potential sampling locations in a reservoir with emphasis on conserved spatial correlation structure.

PubMed

Yenilmez, Firdes; Düzgün, Sebnem; Aksoy, Aysegül

2015-01-01

In this study, kernel density estimation (KDE) was coupled with ordinary two-dimensional kriging (OK) to reduce the number of sampling locations in measurement and kriging of dissolved oxygen (DO) concentrations in Porsuk Dam Reservoir (PDR). Conservation of the spatial correlation structure in the DO distribution was a target. KDE was used as a tool to aid in identification of the sampling locations that would be removed from the sampling network in order to decrease the total number of samples. Accordingly, several networks were generated in which sampling locations were reduced from 65 to 10 in increments of 4 or 5 points at a time based on kernel density maps. DO variograms were constructed, and DO values in PDR were kriged. Performance of the networks in DO estimations were evaluated through various error metrics, standard error maps (SEM), and whether the spatial correlation structure was conserved or not. Results indicated that smaller number of sampling points resulted in loss of information in regard to spatial correlation structure in DO. The minimum representative sampling points for PDR was 35. Efficacy of the sampling location selection method was tested against the networks generated by experts. It was shown that the evaluation approach proposed in this study provided a better sampling network design in which the spatial correlation structure of DO was sustained for kriging.

Scale-dependent variation in forest structures in naturally dynamic boreal forest landscapes

NASA Astrophysics Data System (ADS)

Kulha, Niko; Pasanen, Leena; De Grandpré, Louis; Kuuluvainen, Timo; Aakala, Tuomas

2017-04-01

Natural forest structures vary at multiple spatial scales. This variation reflects the occurrence of driving factors, such as disturbances and variation in soil or topography. To explore and understand the linkages of forest structural characteristics and factors driving their variation, we need to recognize how the structural characteristics vary in relation to spatial scale. This can be achieved by identifying scale-dependent features in forest structure within unmanaged forest landscapes. By identifying these features and examining their relationship with potential driving factors, we can better understand the dynamics of forest structural development. Here, we examine the spatial variation in forest structures at multiple spatial scales, utilizing data from old-growth boreal forests in two regions with contrasting disturbance regimes: northern Finland and north-eastern Québec, Canada ( 67° 45'N, 29° 36'E, 49° 39'N, 67° 55'W, respectively). The three landscapes (4 km2 each) in Finland are dominated by Pinus sylvestris and Picea abies, whereas the two landscapes in Québec are dominated by Abies balsamea and Picea mariana. Québec's forests are a subject to cyclic outbreaks of the eastern spruce budworm, causing extensive mortality especially in A. balsamea-dominated stands. In the Finnish landscapes, gap- to patch-scale disturbances due to tree senescence, fungi and wind, as well as infrequent surface fires in areas dominated by P. sylvestris, prevail. Owing to the differences in the species compositions and the disturbance regimes, we expect differing scales of variation between the landscapes. To quantify patterns of variation, we visually interpret stereopairs of recent aerial photographs. From the photographs, we collect information on forest canopy coverage, species composition and dead wood. For the interpretation, each 4 km2 plot is divided into 0.1ha square cells (4096 per plot). Interpretations are validated against field observations and compiled to raster maps. We analyze the raster maps with Bayesian scale space approach (iBSiZer), which aims in capturing credible variations at different spatial scales. As a result, we can detect structural entities (e.g. patches with higher canopy cover), which deviate credibly from their surroundings. The detected entities can further be linked to specific drivers. Our results show that the role of a particular driving factor varies in relation to spatial scale. For example, in the Finnish landscapes, topoedaphic factors exerted a stronger control on broad-scale forest structural characteristics, whereas recent disturbances (quantified as the amount of dead wood) appeared to play an important role in explaining the smaller scale variation of forest structures. Here, we showcase the methodology used in the detection of scale-dependent forest structural entities and present the results of our analysis of the spatial scales of variation in the natural boreal forest structures.

[Spatial structure analysis and distribution simulation of Therioaphis trifolii population based on geostatistics and GIS].

PubMed

Zhang, Rong; Leng, Yun-fa; Zhu, Meng-meng; Wang, Fang

2007-11-01

Based on geographic information system and geostatistics, the spatial structure of Therioaphis trifolii population of different periods in Yuanzhou district of Guyuan City, the southern Ningxia Province, was analyzed. The spatial distribution of Therioaphis trifolii population was also simulated by ordinary Kriging interpretation. The results showed that Therioaphis trifolii population of different periods was correlated spatially in the study area. The semivariograms of Therioaphis trifolii could be described by exponential model, indicating an aggregated spatial arrangement. The spatial variance varied from 34.13%-48.77%, and the range varied from 8.751-12.049 km. The degree and direction of aggregation showed that the trend was increased gradually from southwest to northeast. The dynamic change of Therioaphis trifolii population in different periods could be analyzed intuitively on the simulated maps of the spatial distribution from the two aspects of time and space, The occurrence position and degree of Therioaphis trifolii to a state of certain time could be determined easily.

Nanosensitive optical coherence tomography for the study of changes in static and dynamic structures

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

Alexandrov, S; Subhash, H; Leahy, M

2014-07-31

We briefly discuss the principle of image formation in Fourier domain optical coherence tomography (OCT). The theory of a new approach to improve dramatically the sensitivity of conventional OCT is described. The approach is based on spectral encoding of spatial frequency. Information about the spatial structure is directly translated from the Fourier domain to the image domain as different wavelengths, without compromising the accuracy. Axial spatial period profiles of the structure are reconstructed for any volume of interest within the 3D OCT image with nanoscale sensitivity. An example of application of the nanoscale OCT to probe the internal structure ofmore » medico-biological objects, the anterior chamber of an ex vivo rat eye, is demonstrated. (laser biophotonics)« less

SPATIAL PATTERNS IN ASSEMBLAGE STRUCTURES OF PELAGIC FORAGE FISH AND ZOOPLANKTON IN WESTERN LAKE SUPERIOR

EPA Science Inventory

This manuscript reports on the spatial distribution of zooplankton and forage fish in western Lake Superior. Fish and zooplankton assemblages are shown to differ substantially in abundance and size structure both between the open lake and nearshore regions and between two differe...