Foreign direct investment in the United States and u.s. Interests.

PubMed

Graham, E M

1991-12-20

Foreign direct investment entered the United States at unprecedented rates during the second half of the 1980s. The result has been much higher levels of foreign ownership of U.S. economic activities than those to which the nation has been accustomed. The reasons for this investment include loss of competitiveness of U.S. firms compared to international rivals as well as attractions to foreign investors of the United States itself. The economic effects of greater levels of foreign ownership are generally positive, although some problems with levels of competition could ensue. National security considerations might cause the United States to place some restrictions on this investment, but other restrictions at the present time appear to be unwarranted.

The neural basis of visual dominance in the context of audio-visual object processing.

PubMed

Schmid, Carmen; Büchel, Christian; Rose, Michael

2011-03-01

Visual dominance refers to the observation that in bimodal environments vision often has an advantage over other senses in human. Therefore, a better memory performance for visual compared to, e.g., auditory material is assumed. However, the reason for this preferential processing and the relation to the memory formation is largely unknown. In this fMRI experiment, we manipulated cross-modal competition and attention, two factors that both modulate bimodal stimulus processing and can affect memory formation. Pictures and sounds of objects were presented simultaneously in two levels of recognisability, thus manipulating the amount of cross-modal competition. Attention was manipulated via task instruction and directed either to the visual or the auditory modality. The factorial design allowed a direct comparison of the effects between both modalities. The resulting memory performance showed that visual dominance was limited to a distinct task setting. Visual was superior to auditory object memory only when allocating attention towards the competing modality. During encoding, cross-modal competition and attention towards the opponent domain reduced fMRI signals in both neural systems, but cross-modal competition was more pronounced in the auditory system and only in auditory cortex this competition was further modulated by attention. Furthermore, neural activity reduction in auditory cortex during encoding was closely related to the behavioural auditory memory impairment. These results indicate that visual dominance emerges from a less pronounced vulnerability of the visual system against competition from the auditory domain. Copyright © 2010 Elsevier Inc. All rights reserved.

A disparity between locomotor economy and territory-holding ability in male house mice.

PubMed

Morris, Jeremy S; Ruff, James S; Potts, Wayne K; Carrier, David R

2017-07-15

Both economical locomotion and physical fighting are important performance traits to many species because of their direct influence on components of Darwinian fitness. Locomotion represents a substantial portion of the total daily energy budget of many animals. Fighting performance often determines individual reproductive fitness through the means of resource control, social dominance and access to mates. However, phenotypic traits that improve either locomotor economy or fighting ability may diminish performance in the other. Here, we tested for a predicted disparity between locomotor economy and competitive ability in wild-derived house mice ( Mus musculus ). We used 8 week social competition trials in semi-natural enclosures to directly measure male competitive ability through territorial control and female occupancy within territories. We also measured oxygen consumption during locomotion for each mouse using running trials in an enclosed treadmill and open-flow respirometry. Our results show that territory-holding males have higher absolute and mass-specific oxygen consumption when running (i.e. reduced locomotor economy) compared with males that do not control territories. This relationship was present both before and after 8 week competition trials in semi-natural enclosures. This disparity between physical competitive ability and economical locomotion may impose viability costs on males in species for which competition over mates is common and may constrain the evolution of behavioral and phenotypic diversity, particularly in natural settings with environmental and resource variability. © 2017. Published by The Company of Biologists Ltd.

76 FR 16810 - Notice of Realty Action: Non-Competitive (Direct) Sale of Public Land in Hot Springs County, WY

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-25

...] Notice of Realty Action: Non-Competitive (Direct) Sale of Public Land in Hot Springs County, WY AGENCY... land in Hot Springs County, Wyoming is being considered for non-competitive (direct) sale to Jim and... land in Hot Springs County, Wyoming has been examined and found suitable for sale under the authority...

A new hammer to crack an old nut: interspecific competitive resource capture by plants is regulated by nutrient supply, not climate.

PubMed

Trinder, Clare J; Brooker, Rob W; Davidson, Hazel; Robinson, David

2012-01-01

Although rarely acknowledged, our understanding of how competition is modulated by environmental drivers is severely hampered by our dependence on indirect measurements of outcomes, rather than the process of competition. To overcome this, we made direct measurements of plant competition for soil nitrogen (N). Using isotope pool-dilution, we examined the interactive effects of soil resource limitation and climatic severity between two common grassland species. Pool-dilution estimates the uptake of total N over a defined time period, rather than simply the uptake of ¹⁵N label, as used in most other tracer experiments. Competitive uptake of N was determined by its available form (NO₃⁻ or NH₄⁺). Soil N availability had a greater effect than the climatic conditions (location) under which plants grew. The results did not entirely support either of the main current theories relating the role of competition to environmental conditions. We found no evidence for Tilman's theory that competition for soil nutrients is stronger at low, compared with high nutrient levels and partial support for Grime's theory that competition for soil nutrients is greater under potentially more productive conditions. These results provide novel insights by demonstrating the dynamic nature of plant resource competition.

A New Hammer to Crack an Old Nut: Interspecific Competitive Resource Capture by Plants Is Regulated by Nutrient Supply, Not Climate

PubMed Central

Trinder, Clare J.; Brooker, Rob W.; Davidson, Hazel; Robinson, David

2012-01-01

Although rarely acknowledged, our understanding of how competition is modulated by environmental drivers is severely hampered by our dependence on indirect measurements of outcomes, rather than the process of competition. To overcome this, we made direct measurements of plant competition for soil nitrogen (N). Using isotope pool-dilution, we examined the interactive effects of soil resource limitation and climatic severity between two common grassland species. Pool-dilution estimates the uptake of total N over a defined time period, rather than simply the uptake of 15N label, as used in most other tracer experiments. Competitive uptake of N was determined by its available form (NO3 − or NH4 +). Soil N availability had a greater effect than the climatic conditions (location) under which plants grew. The results did not entirely support either of the main current theories relating the role of competition to environmental conditions. We found no evidence for Tilman's theory that competition for soil nutrients is stronger at low, compared with high nutrient levels and partial support for Grime's theory that competition for soil nutrients is greater under potentially more productive conditions. These results provide novel insights by demonstrating the dynamic nature of plant resource competition. PMID:22247775

Development of a Competitive Binding Assay System with Recombinant Estrogen Receptors from Multiple Species

EPA Science Inventory

ABSTRACT In the current study, we developed a new system using full-length recombinant baculovirus-expressed estrogen receptors which allows for direct comparison of binding across species. Estrogen receptors representing five vertebrate classes were compared: human (hERα), quai...

Resource competition in plant invasions: emerging patterns and research needs

PubMed Central

Gioria, Margherita; Osborne, Bruce A.

2014-01-01

Invasions by alien plants provide a unique opportunity to examine competitive interactions among plants. While resource competition has long been regarded as a major mechanism responsible for successful invasions, given a well-known capacity for many invaders to become dominant and reduce plant diversity in the invaded communities, few studies have measured resource competition directly or have assessed its importance relative to that of other mechanisms, at different stages of an invasion process. Here, we review evidence comparing the competitive ability of invasive species vs. that of co-occurring native plants, along a range of environmental gradients, showing that many invasive species have a superior competitive ability over native species, although invasive congeners are not necessarily competitively superior over native congeners, nor are alien dominants are better competitors than native dominants. We discuss how the outcomes of competition depend on a number of factors, such as the heterogeneous distribution of resources, the stage of the invasion process, as well as phenotypic plasticity and evolutionary adaptation, which may result in increased or decreased competitive ability in both invasive and native species. Competitive advantages of invasive species over natives are often transient and only important at the early stages of an invasion process. It remains unclear how important resource competition is relative to other mechanisms (competition avoidance via phenological differences, niche differentiation in space associated with phylogenetic distance, recruitment and dispersal limitation, indirect competition, and allelopathy). Finally, we identify the conceptual and methodological issues characterizing competition studies in plant invasions, and we discuss future research needs, including examination of resource competition dynamics and the impact of global environmental change on competitive interactions between invasive and native species. PMID:25324851

Resource competition in plant invasions: emerging patterns and research needs.

PubMed

Gioria, Margherita; Osborne, Bruce A

2014-01-01

Invasions by alien plants provide a unique opportunity to examine competitive interactions among plants. While resource competition has long been regarded as a major mechanism responsible for successful invasions, given a well-known capacity for many invaders to become dominant and reduce plant diversity in the invaded communities, few studies have measured resource competition directly or have assessed its importance relative to that of other mechanisms, at different stages of an invasion process. Here, we review evidence comparing the competitive ability of invasive species vs. that of co-occurring native plants, along a range of environmental gradients, showing that many invasive species have a superior competitive ability over native species, although invasive congeners are not necessarily competitively superior over native congeners, nor are alien dominants are better competitors than native dominants. We discuss how the outcomes of competition depend on a number of factors, such as the heterogeneous distribution of resources, the stage of the invasion process, as well as phenotypic plasticity and evolutionary adaptation, which may result in increased or decreased competitive ability in both invasive and native species. Competitive advantages of invasive species over natives are often transient and only important at the early stages of an invasion process. It remains unclear how important resource competition is relative to other mechanisms (competition avoidance via phenological differences, niche differentiation in space associated with phylogenetic distance, recruitment and dispersal limitation, indirect competition, and allelopathy). Finally, we identify the conceptual and methodological issues characterizing competition studies in plant invasions, and we discuss future research needs, including examination of resource competition dynamics and the impact of global environmental change on competitive interactions between invasive and native species.

Improving Genomic Prediction in Cassava Field Experiments by Accounting for Interplot Competition

PubMed Central

Elias, Ani A.; Rabbi, Ismail; Kulakow, Peter; Jannink, Jean-Luc

2018-01-01

Plants competing for available resources is an unavoidable phenomenon in a field. We conducted studies in cassava (Manihot esculenta Crantz) in order to understand the pattern of this competition. Taking into account the competitive ability of genotypes while selecting parents for breeding advancement or commercialization can be very useful. We assumed that competition could occur at two levels: (i) the genotypic level, which we call interclonal, and (ii) the plot level irrespective of the type of genotype, which we call interplot competition or competition error. Modification in incidence matrices was applied in order to relate neighboring genotype/plot to the performance of a target genotype/plot with respect to its competitive ability. This was added into a genomic selection (GS) model to simultaneously predict the direct and competitive ability of a genotype. Predictability of the models was tested through a 10-fold cross-validation method repeated five times. The best model was chosen as the one with the lowest prediction root mean squared error (pRMSE) compared to that of the base model having no competitive component. Results from our real data studies indicated that <10% increase in accuracy was achieved with GS-interclonal competition model, but this value reached up to 25% with a GS-competition error model. We also found that the competitive influence of a cassava clone is not just limited to the adjacent neighbors but spreads beyond them. Through simulations, we found that a 26% increase of accuracy in estimating trait genotypic effect can be achieved even in the presence of high competitive variance. PMID:29358232

Improving Genomic Prediction in Cassava Field Experiments by Accounting for Interplot Competition.

PubMed

Elias, Ani A; Rabbi, Ismail; Kulakow, Peter; Jannink, Jean-Luc

2018-03-02

Plants competing for available resources is an unavoidable phenomenon in a field. We conducted studies in cassava ( Manihot esculenta Crantz) in order to understand the pattern of this competition. Taking into account the competitive ability of genotypes while selecting parents for breeding advancement or commercialization can be very useful. We assumed that competition could occur at two levels: (i) the genotypic level, which we call interclonal, and (ii) the plot level irrespective of the type of genotype, which we call interplot competition or competition error. Modification in incidence matrices was applied in order to relate neighboring genotype/plot to the performance of a target genotype/plot with respect to its competitive ability. This was added into a genomic selection (GS) model to simultaneously predict the direct and competitive ability of a genotype. Predictability of the models was tested through a 10-fold cross-validation method repeated five times. The best model was chosen as the one with the lowest prediction root mean squared error (pRMSE) compared to that of the base model having no competitive component. Results from our real data studies indicated that <10% increase in accuracy was achieved with GS-interclonal competition model, but this value reached up to 25% with a GS-competition error model. We also found that the competitive influence of a cassava clone is not just limited to the adjacent neighbors but spreads beyond them. Through simulations, we found that a 26% increase of accuracy in estimating trait genotypic effect can be achieved even in the presence of high competitive variance. Copyright © 2018 Elias et al.

Activity Demands During Multi-Directional Team Sports: A Systematic Review.

PubMed

Taylor, Jeffrey B; Wright, Alexis A; Dischiavi, Steven L; Townsend, M Allison; Marmon, Adam R

2017-12-01

Late-stage rehabilitation programs often incorporate 'sport-specific' demands, but may not optimally simulate the in-game volume or intensity of such activities as sprinting, cutting, jumping, and lateral movement. The aim of this review was to characterize, quantify, and compare straight-line running and multi-directional demands during sport competition. A systematic review of PubMed, CINAHL, SPORTDiscus, and Cochrane Central Register of Controlled Trials databases was conducted. Studies that reported time-motion analysis data on straight-line running, accelerations/decelerations, activity changes, jumping, cutting, or lateral movement over the course of an entire competition in a multi-directional sport (soccer, basketball, lacrosse, handball, field hockey, futsal, volleyball) were included. Data was organized based on sport, age level, and sex and descriptive statistics of the frequency, intensity, time, and volume of the characteristics of running and multi-directional demands were extracted from each study. Eighty-one studies were included in the review (n = 47 soccer, n = 11 basketball, n = 9 handball, n = 7 field hockey, n = 3 futsal, n = 4 volleyball). Variability of sport demand data was found across sports, sexes, and age levels. Specifically, soccer and field hockey demanded the most volume of running, while basketball required the highest ratio of high-intensity running to sprinting. Athletes change activity between 500 and 3000 times over the course of a competition, or once every 2-4 s. Studies of soccer reported the most frequent cutting (up to 800 per game), while studies of basketball reported the highest frequency of lateral movement (up to 450 per game). Basketball (42-56 per game), handball (up to 90 per game), and volleyball (up to 35 per game) were found to require the most jumping. These data may provide an incomplete view of an athlete's straight-line running load, considering that only competition and not practice data was provided. Considerable variability exists in the demands of straight-line running and multi-directional demands across sports, competition levels, and sexes, indicating the need for sports medicine clinicians to design future rehabilitation programs with improved specificity (including the type of activity and dosage) to these demands.

78 FR 29157 - Certain Digital Models, Digital Data, and Treatment Plans for Use, in Making Incremental Dental...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-17

... INTERNATIONAL TRADE COMMISSION Certain Digital Models, Digital Data, and Treatment Plans for Use... conditions in the United States economy, the production of like or directly competitive articles in the..., competitive conditions in the United States economy, the production of like or directly competitive articles...

75 FR 48733 - Self-Regulatory Organizations; EDGA Exchange, Inc.; Notice of Filing and Immediate Effectiveness...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-11

... competitive pricing structure designed to incent market participants to direct their order flow to the... highly competitive market in which market participants can readily direct order flow to competing venues... to all Members. The Exchange believes the fees and credits remain competitive with those charged by...

76 FR 47285 - Self-Regulatory Organizations; EDGX Exchange, Inc.; Notice of Filing and Immediate Effectiveness...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-04

... competitive pricing structure designed to incent market participants to direct their order flow to the... a highly competitive market in which market participants can readily direct order flow to competing... uniformly to all Members. The Exchange believes the fees and credits remain competitive with those charged...

45 CFR 2522.710 - What are my evaluation requirements?

Code of Federal Regulations, 2010 CFR

2010-10-01

... subgrantees, as you deem appropriate. (b) If you are a State competitive or direct Corporation AmeriCorps... submit the evaluation with any application to the Corporation for competitive funds as required in § 2522.730 of this subpart. (c) If you are a State competitive or direct Corporation AmeriCorps grantee whose...

45 CFR 2522.710 - What are my evaluation requirements?

Code of Federal Regulations, 2011 CFR

2011-10-01

... subgrantees, as you deem appropriate. (b) If you are a State competitive or direct Corporation AmeriCorps... submit the evaluation with any application to the Corporation for competitive funds as required in § 2522.730 of this subpart. (c) If you are a State competitive or direct Corporation AmeriCorps grantee whose...

The Why, Where, When and How of Ad Competitions.

ERIC Educational Resources Information Center

Marra, James L.

1988-01-01

Discusses the pedagogical benefits of advertising competitions, and describes five national competitions available to students, including Nissan Student Advertising Contest, Philip Morris Marketing Communications Competition for Students, Direct Marketing Collegiate Echo Competition, and American Advertising Federation National Student Advertising…

Their pain, our pleasure: stereotype content and schadenfreude.

PubMed

Cikara, Mina; Fiske, Susan T

2013-09-01

People often fail to empathize with others, and sometimes even experience schadenfreude-pleasure at others' misfortunes. One potent predictor of schadenfreude is envy, which, according to the stereotype content model, is elicited by high-status, competitive targets. Here we review our recent research program investigating the relationships among stereotypes, envy, schadenfreude, and harm. Experiment 1 demonstrates that stereotypes are sufficient to influence affective responses to targets' misfortunes; participants not only report feeling less negative when misfortunes befall high-status, competitive targets as compared to other targets, they also smile more (assessed with facial EMG). Experiment 2 replicates the self-report findings from Experiment 1 and assesses behavioral tendencies toward envied targets; participants are more willing to endorse harming high-status, competitive targets as compared to other targets. Experiment 3 turns off the schadenfreude response by manipulating status and competition-relevant information regarding envied targets. Finally, Experiment 4 investigates affective and neural markers of intergroup envy and schadenfreude in the context of a long-standing sports rivalry and the extent to which neurophysiological correlates of schadenfreude are related to self-reported likelihood of harming rival team fans. We conclude with implications and future directions. © 2013 New York Academy of Sciences.

Their pain, our pleasure: stereotype content and schadenfreude

PubMed Central

Cikara, Mina; Fiske, Susan T.

2015-01-01

People often fail to empathize with others, and sometimes even experience schadenfreude – pleasure at others' misfortunes. One potent predictor of schadenfreude is envy, which, according to the stereotype content model, is elicited by high-status, competitive targets. Here we review our recent research program investigating the relationships among stereotypes, envy, schadenfreude, and harm. Experiment 1 demonstrates that stereotypes are sufficient to influence affective responses to targets' misfortunes; participants not only report feeling less negative when misfortunes befall high-status, competitive targets as compared to other targets, they also smile more (assessed with facial EMG). Experiment 2 replicates the self-report findings from Experiment 1 and assesses behavioral tendencies toward envied targets; participants are more willing to endorse harming high-status, competitive targets as compared to other targets. Experiment 3 turns off the schadenfreude response by manipulating status and competition-relevant information regarding envied targets. Finally, Experiment 4 investigates affective and neural markers of intergroup envy and schadenfreude in the context of a long-standing sports rivalry and the extent to which neurophysiological correlates of schadenfreude are related to self-reported likelihood of harming rival team fans. We conclude with implications and future directions. PMID:25708079

Evolution of larval competitiveness and associated life-history traits in response to host shifts in a seed beetle.

PubMed

Fox, C W; Messina, F J

2018-02-01

Resource competition is frequently strong among parasites that feed within small discrete resource patches, such as seeds or fruits. The properties of a host can influence the behavioural, morphological and life-history traits of associated parasites, including traits that mediate competition within the host. For seed parasites, host size may be an especially important determinant of competitive ability. Using the seed beetle, Callosobruchus maculatus, we performed replicated, reciprocal host shifts to examine the role of seed size in determining larval competitiveness and associated traits. Populations ancestrally associated with either a small host (mung bean) or a large one (cowpea) were switched to each other's host for 36 generations. Compared to control lines (those remaining on the ancestral host), lines switched from the small host to the large host evolved greater tolerance of co-occurring larvae within seeds (indicated by an increase in the frequency of small seeds yielding two adults), smaller egg size and higher fecundity. Each change occurred in the direction predicted by the traits of populations already adapted to cowpea. However, we did not observe the expected decline in adult mass following the shift to the larger host. Moreover, lines switched from the large host (cowpea) to the small host (mung bean) did not evolve the predicted increase in larval competitiveness or egg size, but did exhibit the predicted increase in body mass. Our results thus provide mixed support for the hypothesis that host size determines the evolution of competition-related traits of seed beetles. Evolutionary responses to the two host shifts were consistent among replicate lines, but the evolution of larval competition was asymmetric, with larval competitiveness evolving as predicted in one direction of host shift, but not the reverse. Nevertheless, our results indicate that switching hosts is sufficient to produce repeatable and rapid changes in the competition strategy and fitness-related traits of insect populations. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

RE-evolution of durum wheat by restoring the hardness locus

USDA-ARS?s Scientific Manuscript database

Durum wheat is an important crop worldwide. In many areas, durum wheat appears to have competitive yield and biotic and abiotic advantages over bread wheat. What limits durum production? In one respect, the comparatively more limited processing and food functionality. Two traits directly relate to t...

76 FR 60788 - Patient Protection and Affordable Care Act; Establishment of Exchanges and Qualified Health Plans...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-30

... for health insurance issuers related to reinsurance, risk corridors, and risk adjustment consistent... marketplaces for individuals and small employers to directly compare available private health insurance options... January 1, 2014, would help enhance competition in the health insurance market, improve choice of...

[Importance of perceived competition and motivation to the mental health of college athletes].

PubMed

Castillo, Isabel; Molina-García, Javier; Alvarez, Octavio

2010-01-01

This research analyzes the direct and indirect relationships among self-motivation, perceived competition and psychological well-being and ill-being. Data from 491 Spanish college students (299 men and 192 women) who practice sports were collected using a cross-sectional design. Statistical analyses were carried out using structural equation modeling. Psychological well-being was directly fostered by perceived competition and indirectly by self- motivation. Furthermore, perceived competition was negatively associated with psychological ill-being. Perceived competition and self-motivation are important to the psychological well-being of college students and to avoiding ill-being.

A research model of health-care competition and customer satisfaction.

PubMed

Asoh, Derek A; Rivers, Patrick A

2007-11-01

In all industries, competition among businesses has long been encouraged as a mechanism to increase value for customers. In other words, competition ensures the provision of better products and services to satisfy the needs of customers. Various perspectives of competition, the nature of service quality, health-care system costs and customer satisfaction in health care are examined. A model of the relationship among these variables is developed. The model depicts customer satisfaction as an outcome measure directly dependent on competition. Quality of care and health-care system costs, while also directly dependent on competition, are considered as determinants of customer satisfaction as well. The model is discussed in the light of propositions for empirical research.

Insect herbivores drive real-time ecological and evolutionary change in plant populations.

PubMed

Agrawal, Anurag A; Hastings, Amy P; Johnson, Marc T J; Maron, John L; Salminen, Juha-Pekka

2012-10-05

Insect herbivores are hypothesized to be major factors affecting the ecology and evolution of plants. We tested this prediction by suppressing insects in replicated field populations of a native plant, Oenothera biennis, which reduced seed predation, altered interspecific competitive dynamics, and resulted in rapid evolutionary divergence. Comparative genotyping and phenotyping of nearly 12,000 O. biennis individuals revealed that in plots protected from insects, resistance to herbivores declined through time owing to changes in flowering time and lower defensive ellagitannins in fruits, whereas plant competitive ability increased. This independent real-time evolution of plant resistance and competitive ability in the field resulted from the relaxation of direct selective effects of insects on plant defense and through indirect effects due to reduced herbivory on plant competitors.

Better to give and to compete? Prosocial and competitive motives as interactive predictors of citizenship behavior.

PubMed

Cardador, M Teresa; Wrzesniewski, Amy

2015-01-01

Research has returned mixed results concerning the relationship between prosocial motivation and citizenship behavior. Building from research suggesting that mixed motives might explain these equivocal findings, we conducted two field studies examining the interaction between prosocial and competitive motives and two types of citizenship behavior. Prosocial motivation, but not competitive motivation, was positively related to citizenship behavior directed at others, though this relationship was weakened when prosocial motives were accompanied by competitive motives. Prosocial motives compensated for weak competitive motives to predict citizenship behavior directed toward the organization. Our studies expand research on prosocial and competitive motivation, mixed-motives, and citizenship behavior. Further, they carry personnel implications given that many organizations seek to hire employees high on both competitive and prosocial motivation.

Competitive testing of health behavior theories: how do benefits, barriers, subjective norm, and intention influence mammography behavior?

PubMed Central

Murphy, Caitlin C.; Vernon, Sally W.; Diamond, Pamela M.; Tiro, Jasmin A.

2013-01-01

Background Competitive hypothesis testing may explain differences in predictive power across multiple health behavior theories. Purpose We tested competing hypotheses of the Health Belief Model (HBM) and Theory of Reasoned Action (TRA) to quantify pathways linking subjective norm, benefits, barriers, intention, and mammography behavior. Methods We analyzed longitudinal surveys of women veterans randomized to the control group of a mammography intervention trial (n=704). We compared direct, partial mediation, and full mediation models with Satorra-Bentler χ2 difference testing. Results Barriers had a direct and indirect negative effect on mammography behavior; intention only partially mediated barriers. Benefits had little to no effect on behavior and intention; however, it was negatively correlated with barriers. Subjective norm directly affected behavior and indirectly affected intention through barriers. Conclusions Our results provide empiric support for different assertions of HBM and TRA. Future interventions should test whether building subjective norm and reducing negative attitudes increases regular mammography. PMID:23868613

Mixed martial arts induces significant fatigue and muscle damage up to 24 hours post-combat.

PubMed

Ghoul, Nihel; Tabben, Montassar; Miarka, Bianca; Tourny, Claire; Chamari, Karim; Coquart, Jeremy

2017-06-22

This study investigates the physiological/physical responses to a simulated mixed martial arts (MMA) competition over 24 hr. Twelve fighters performed a simulated MMA competition, consisting of three 5-min MMA matches. Physiological/physical data were assessed before (Trest), directly after round 1 (Trd1), round 2 (Trd2) and round 3 (Trd3), and then 30-min (Trecovery30min) and/or 24-hr (Trecovery24h) post-competition. Heart rate (HR), rating of perceived exertion (RPE) and blood lactate concentration ([La]) were assessed at Trest, Trd1, Trd2 and Trd3. Biological data were collected at Trest, Trd3, Trecovery30min and Trecovery24h. Physical tests were performed at Trest, Trecovery30min and Trecovery24h. HR, RPE and [La] were high during competition. Leukocytes, hemoglobin, total protein and glycemia were increased at Trd3 compared with all other time points (p<0.05). Cortisol was increased at Trd3 compared with Trest and Trecovery24h (p<0.05). Testosterone was higher at Trd3 and Trecovery30min than Trest (p<0.001). Higher values of uric acid were noted during recovery periods (p<0.001). Lactate dehydrogenase was lower at Trest compared with Trd3, Trecovery30min and Trecovery24h (p<0.05). Countermovement jump was higher at Trest than Trecovery30min (p=0.020). Consequently, MMA is a high-intensity intermittent combat sport that induces significant fatigue and muscle damage, both of which are still present 24-hr post-competition.

Fuel cells and batteries: Competition or separate paths?

NASA Astrophysics Data System (ADS)

Ilic, D.; Holl, K.; Birke, P.; Wöhrle, T.; Birke-Salam, F.; Perner, A.; Haug, P.

This article in honor of 60th anniversary of Prof. Dr. J. Garche shows some historical and general aspects of batteries and fuel cells. Our most innovative product PoLiFlex™ will be highlighted and compared with the direct methanol fuel cell (DMFC), which is sometimes considered as a replacement for batteries.

78 FR 47780 - Notice of Determinations Regarding Eligibility to Apply for Worker Adjustment Assistance

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-06

... services like or directly competitive with articles produced or services supplied by such firm have... produced directly using services supplied by such firm, have increased; and (4) The increase in imports... articles or supply of services like or directly competitive with those produced/supplied by the workers...

76 FR 81987 - Notice of Determinations Regarding Eligibility To Apply for Worker Adjustment Assistance

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-29

... or services like or directly competitive with articles produced or services supplied by such firm... which are produced directly using services supplied by such firm, have increased; and (4) the increase... production of articles or supply of services like or directly competitive with those produced/supplied by the...

77 FR 1950 - Notice of Determinations Regarding Eligibility To Apply for Worker Adjustment Assistance

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2012-01-12

... or services like or directly competitive with articles produced or services supplied by such firm... which are produced directly using services supplied by such firm, have increased; and (4) The increase... production of articles or supply of services like or directly competitive with those produced/supplied by the...

77 FR 29363 - Notice of Determinations Regarding Eligibility To Apply for Worker Adjustment Assistance

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2012-05-17

... or services like or directly competitive with articles produced or services supplied by such firm... which are produced directly using services supplied by such firm, have increased; and (4) The increase... production of articles or supply of services like or directly competitive with those produced/supplied by the...

Body image, binge eating, and bulimia nervosa in male bodybuilders.

PubMed

Goldfield, Gary S; Blouin, Arthur G; Woodside, D Blake

2006-03-01

Male bodybuilders (MBB) exhibit more severe body dissatisfaction, bulimic eating behaviour, and negative psychological characteristics, compared with male athletic and nonathletic control subjects, but few studies have directly compared MBB and men with eating disorders. This study compared men with bulimia nervosa (MBN), competitive male bodybuilders (CMBB), and recreational male bodybuilders (RMBB) on a broad range of eating attitudes and behaviours and psychological characteristics to more accurately determine similarities and differences among these groups. Anonymous questionnaires, designed to assess eating attitudes, body image, weight and shape preoccupation, prevalence of binge eating, weight loss practices, lifetime rates of eating disorders, anabolic androgenic steroid (AAS) use, and general psychological factors, were completed by 22 MBN, 27 CMBB, and 25 RMBB. High rates of weight and shape preoccupation, extreme body modification practices, binge eating, and bulimia nervosa (BN) were reported among MBB, especially among those who competed. CMBB reported higher rates of binge eating, BN, and AAS use compared with RMBB, but exhibited less eating-related and general psychopathology compared with MBN. Few psychological differences were found between CMBB and RMBB. MBB, especially competitors, and MBN appear to share many eating-related features but few general psychological ones. Longitudinal research is needed to determine whether men with a history of disordered eating or BN disproportionately gravitate to competitive bodybuildin and (or) whether competitive bodybuilding fosters disordered eating, BN, and AAS use.

Principles of parametric estimation in modeling language competition

PubMed Central

Zhang, Menghan; Gong, Tao

2013-01-01

It is generally difficult to define reasonable parameters and interpret their values in mathematical models of social phenomena. Rather than directly fitting abstract parameters against empirical data, we should define some concrete parameters to denote the sociocultural factors relevant for particular phenomena, and compute the values of these parameters based upon the corresponding empirical data. Taking the example of modeling studies of language competition, we propose a language diffusion principle and two language inheritance principles to compute two critical parameters, namely the impacts and inheritance rates of competing languages, in our language competition model derived from the Lotka–Volterra competition model in evolutionary biology. These principles assign explicit sociolinguistic meanings to those parameters and calculate their values from the relevant data of population censuses and language surveys. Using four examples of language competition, we illustrate that our language competition model with thus-estimated parameter values can reliably replicate and predict the dynamics of language competition, and it is especially useful in cases lacking direct competition data. PMID:23716678

Principles of parametric estimation in modeling language competition.

PubMed

Zhang, Menghan; Gong, Tao

2013-06-11

It is generally difficult to define reasonable parameters and interpret their values in mathematical models of social phenomena. Rather than directly fitting abstract parameters against empirical data, we should define some concrete parameters to denote the sociocultural factors relevant for particular phenomena, and compute the values of these parameters based upon the corresponding empirical data. Taking the example of modeling studies of language competition, we propose a language diffusion principle and two language inheritance principles to compute two critical parameters, namely the impacts and inheritance rates of competing languages, in our language competition model derived from the Lotka-Volterra competition model in evolutionary biology. These principles assign explicit sociolinguistic meanings to those parameters and calculate their values from the relevant data of population censuses and language surveys. Using four examples of language competition, we illustrate that our language competition model with thus-estimated parameter values can reliably replicate and predict the dynamics of language competition, and it is especially useful in cases lacking direct competition data.

Localised and delocalised optically induced conversion of composite glow peak 5 in LiF:Mg,Ti (TLD-100) to glow peak 4 as a function of postirradiation annealing temperature.

PubMed

Horowitz, Y S; Einav, Y; Biderman, S; Oster, L

2002-01-01

The composite structure of glow peak 5 in LiF:Mg,Ti (TLD-100) has been investigated using optical bleaching by 310 nm (4 eV) light. The glow peak conversion efficiency of peak 5a (Tm = 187 degrees C) to peak 4 traps is very high at a value of 3+/-0.5 (1 SD) whereas the glow peak conversion efficiency of peak 5 (Tm = 205 degrees C) to peak 4 traps is 0.0026+/-0.0012 (1 SD). The high conversion efficiency of peak 5a to peak 4 arises from direct optical ionisation of the electron in the electron-hole pair. leaving behind a singly-trapped hole (peak 4), a direct mechanism, relatively free of competitive mechanisms. Optical ionisation of the 'singly-trapped' electron (peak 5), however, can lead to peak 4 only via multi-stage mechanisms involving charge carrier transport in the valence and conduction bands, a mechanism subject to competitive processes. The conduction/valence band competitive processes lead to the factor of one thousand decrease in the conversion efficiency of peak 5 compared to peak 5a.

75 FR 21037 - Notice of Realty Action: Proposed Non-Competitive (Direct) Sales of Public Lands, Boulder County, CO

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-22

...-69205] Notice of Realty Action: Proposed Non-Competitive (Direct) Sales of Public Lands, Boulder County... for direct sale to parties at no less than the appraised fair market value (FMV) to resolve historical... disposal of these parcels from Federal ownership. These sales are consistent with Bureau of Land Management...

Optimal Contrast: Competition between Two Referents Improves Word Learning

ERIC Educational Resources Information Center

Zosh, Jennifer M.; Brinster, Meredith; Halberda, Justin

2013-01-01

Does making an inference lead to better learning than being instructed directly? Two experiments evaluated preschoolers' ability to learn new words, comparing their memory for words learned via inference or instruction. On Inference trials, one familiar and one novel object was presented and children were asked to "Point at the [object name (i.e.,…

Underground friends or enemies: model plants help to unravel direct and indirect effects of arbuscular mycorrhizal fungi on plant competition.

PubMed

Facelli, Evelina; Smith, Sally E; Facelli, José M; Christophersen, Helle M; Andrew Smith, F

2010-03-01

*We studied the effects of two arbuscular mycorrhizal (AM) fungi, singly or together, on the outcome of competition between a host (tomato cultivar, wild-type (WT)) and a surrogate nonhost (rmc, a mycorrhiza-defective mutant of WT) as influenced by the contributions of the direct and AM phosphorus (P) uptake pathways to plant P. *We grew plants singly or in pairs of the same or different genotypes (inoculated or not) in pots containing a small compartment with (32)P-labelled soil accessible to AM fungal hyphae and determined expression of orthophosphate (P(i)) transporter genes involved in both AM and direct P uptake. *Gigaspora margarita increased WT competitive effects on rmc. WT and rmc inoculated with Glomus intraradices both showed growth depressions, which were mitigated when G. margarita was present. Orthophosphate transporter gene expression and (32)P transfer showed that the AM pathway operated in single inoculated WT, but not in rmc. *Effects of AM fungi on plant competition depended on the relative contributions of AM and direct pathways of P uptake. Glomus intraradices reduced the efficiency of direct uptake in both WT and rmc. The two-fungus combination showed that interactions between fungi are important in determining outcomes of plant competition.

Habitat fragmentation and interspecific competition: Implications for lynx conservation [Chapter 4

Treesearch

Steven W. Buskirk

2000-01-01

Habitat fragmentation and interspecific competition are two important forces that potentially affect lynx populations. Fragmentation operates by various mechanisms, including direct habitat loss, vehicle collisions and behavioral disturbance from roads, and changes in landscape features such as edges. Competition takes two forms: Exploitation competition involves...

The Decline of Direct Newspaper Competition.

ERIC Educational Resources Information Center

Rosse, James N.

1980-01-01

Describes the decline of direct newspaper competition in terms of the loss of effective newspaper market segmentation. Examines the following influences on market segmentation: shift in advertising demand, advertiser preferences for differentiated audiences, shift in subscriber demand, growth of alternative media, increasing production costs, and…

Negligible effect of competition on coral colony growth.

PubMed

Álvarez-Noriega, Mariana; Baird, Andrew H; Dornelas, Maria; Madin, Joshua S; Connolly, Sean R

2018-06-01

Competition is an important determinant of assemblage structure and population regulation, often resulting in decreased growth, fecundity or survival. In corals, most studies testing for an effect of competition on demographic traits, such as growth, have been experimental and often impose very high levels of competition upon colonies. To more realistically assess the role of competition on coral traits, multispecies studies in the wild are required. Here, we use 5 yr of data that includes 11 coral species on the reef crest at Lizard Island on the Great Barrier Reef to quantify the effect of competition on growth. Additionally, we test whether species differ in their susceptibility to direct-contact (overgrowth and digestion) and overtopping competition, and whether species from some morphological groups are more likely to compete with one another than with species from other morphological groups. We also investigate the relationships between competitive ability and three key traits: growth rate, mechanical stability and fecundity. In contrast to most previous work using field manipulations of competition, we found a negligible effect of competition on growth. Acropora species consistently won overtopping encounters but lost in direct-contact encounters, and these results were consistent among the four Acropora morphological groups. In contrast, the massive Goniastrea spp. were poor at overtopping but generally won direct-contact encounters. Only tabular colonies were disproportionally more likely to compete against one another than with other morphologies. This propensity increases intraspecific relative to interspecific competition, a phenomenon that can promote coexistence when it is present among dominant competitors. Good competitors grew more quickly and had higher fecundity but were less mechanically stable, implying a tradeoff between performance during disturbance vs. performance in the absence of disturbance. We conclude that competition among adults is less likely to influence community dynamics than previously thought. If competition does have an effect, it is more likely to occur at life-stages other than adults. © 2018 by the Ecological Society of America.

A novel method of comparing mating success and survival reveals similar sexual and viability selection for mobility traits in female tree crickets.

PubMed

Ercit, K; Gwynne, D T

2016-06-01

The relationship between sexual and viability selection in females is necessarily different than that in males, as investment in sexual traits potentially comes at the expense of both fecundity and survival. Accordingly, females do not usually invest in sexually selected traits. However, direct benefits obtained from mating, such as nuptial gifts, may encourage competition among females and subsidize investment into sexually selected traits. We compared sexual and viability selection on female tree crickets Oecanthus nigricornis, a species where females mate frequently to obtain nuptial gifts and sexual selection on females is likely. If male choice determines female mating success in this species, we expect sexual selection for fecundity traits, as males of many species prefer more fecund females. Alternatively, intrasexual scramble or combat competition on females may select for larger jumping legs or wider heads (respectively). We estimated mating success in wild caught crickets using microsatellite analysis of stored sperm and estimated relative viability by comparing surviving female O. nigricornis to those captured by a common wasp predator. In support of the scramble competition hypothesis, we found sexual selection for females with larger hind legs and narrower heads. We also found stabilizing viability selection for intermediate head width and hind leg size. As predicted, traits under viability and sexual selection were very similar, and the direction of that selection was not opposing. However, because the shape of sexual and viability selection differs, these episodes of selection may favour slightly different trait sizes. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

Evolution and control of the phase competition morphology in a manganite film

NASA Astrophysics Data System (ADS)

Zhou, Haibiao; Wang, Lingfei; Hou, Yubin; Huang, Zhen; Lu, Qingyou; Wu, Wenbin

2015-11-01

The competition among different phases in perovskite manganites is pronounced since their energies are very close under the interplay of charge, spin, orbital and lattice degrees of freedom. To reveal the roles of underlying interactions, many efforts have been devoted towards directly imaging phase transitions at microscopic scales. Here we show images of the charge-ordered insulator (COI) phase transition from a pure ferromagnetic metal with reducing field or increasing temperature in a strained phase-separated manganite film, using a home-built magnetic force microscope. Compared with the COI melting transition, this reverse transition is sharp, cooperative and martensitic-like with astonishingly unique yet diverse morphologies. The COI domains show variable-dimensional growth at different temperatures and their distribution can illustrate the delicate balance of the underlying interactions in manganites. Our findings also display how phase domain engineering is possible and how the phase competition can be tuned in a controllable manner.

Evolution and control of the phase competition morphology in a manganite film.

PubMed

Zhou, Haibiao; Wang, Lingfei; Hou, Yubin; Huang, Zhen; Lu, Qingyou; Wu, Wenbin

2015-11-25

The competition among different phases in perovskite manganites is pronounced since their energies are very close under the interplay of charge, spin, orbital and lattice degrees of freedom. To reveal the roles of underlying interactions, many efforts have been devoted towards directly imaging phase transitions at microscopic scales. Here we show images of the charge-ordered insulator (COI) phase transition from a pure ferromagnetic metal with reducing field or increasing temperature in a strained phase-separated manganite film, using a home-built magnetic force microscope. Compared with the COI melting transition, this reverse transition is sharp, cooperative and martensitic-like with astonishingly unique yet diverse morphologies. The COI domains show variable-dimensional growth at different temperatures and their distribution can illustrate the delicate balance of the underlying interactions in manganites. Our findings also display how phase domain engineering is possible and how the phase competition can be tuned in a controllable manner.

No difference in the competitive ability of introduced and native Trifolium provenances when grown with soil biota from their introduced and native ranges

PubMed Central

Shelby, Natasha; Hulme, Philip E.; van der Putten, Wim H.; McGinn, Kevin J.; Weser, Carolin; Duncan, Richard P.

2016-01-01

The evolution of increased competitive ability (EICA) hypothesis could explain why some introduced plant species perform better outside their native ranges. The EICA hypothesis proposes that introduced plants escape specialist pathogens or herbivores leading to selection for resources to be reallocated away from defence and towards greater competitive ability. We tested the hypothesis that escape from soil-borne enemies has led to increased competitive ability in three non-agricultural Trifolium (Fabaceae) species native to Europe that were introduced to New Zealand in the 19th century. Trifolium performance is intimately tied to rhizosphere biota. Thus, we grew plants from one introduced (New Zealand) and two native (Spain and the UK) provenances for each of three species in pots inoculated with soil microbiota collected from the rhizosphere beneath conspecifics in the introduced and native ranges. Plants were grown singly and in competition with conspecifics from a different provenance in order to compare competitive ability in the presence of different microbial communities. In contrast to the predictions of the EICA hypothesis, we found no difference in the competitive ability of introduced and native provenances when grown with soil microbiota from either the native or introduced range. Although plants from introduced provenances of two species grew more slowly than native provenances in native-range soils, as predicted by the EICA hypothesis, plants from the introduced provenance were no less competitive than native conspecifics. Overall, the growth rate of plants grown singly was a poor predictor of their competitive ability, highlighting the importance of directly quantifying plant performance in competitive scenarios, rather than relying on surrogate measures such as growth rate. PMID:26969431

Differential reward responses during competition against in- and out-of-network others.

PubMed

Fareri, Dominic S; Delgado, Mauricio R

2014-04-01

Social interactions occur within a variety of different contexts--cooperative/competitive--and often involve members of our social network. Here, we investigated whether social network modulated the value placed on positive outcomes during a competitive context. Eighteen human participants played a simple card-guessing game with three different competitors: a close friend (in-network), a confederate (out-of-network) and a random number generator (non-social condition) while undergoing functional magnetic resonance imaging. Neuroimaging results at the time of outcome receipt demonstrated a significant main effect of competitor across multiple regions of medial prefrontal cortex, with Blood Oxygen Level Dependent (BOLD) responses strongest when competing against one's friend compared with all other conditions. Striatal BOLD responses demonstrated a more general sensitivity to positive compared with negative monetary outcomes, which an exploratory analysis revealed to be stronger when interacting with social, compared with non-social, competitors. Interestingly, a Granger causality analysis indicated directed influences sent from an medial prefrontal cortex (mPFC) region, which shows social network differentiation of outcomes, and the ventral striatum bilaterally. Our results suggest that when competing against others of varying degrees of social network, mPFC differentially values these outcomes, perhaps treating in-network outcomes as more informative, leaving the striatum to more general value computations.

5 CFR 1.2 - Extent of the competitive service.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Extent of the competitive service. 1.2... DEFINITIONS (RULE I) § 1.2 Extent of the competitive service. The competitive service shall include: (a) All... subject to the civil service laws by statute. OPM is authorized and directed to determine finally whether...

5 CFR 1.2 - Extent of the competitive service.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Extent of the competitive service. 1.2... DEFINITIONS (RULE I) § 1.2 Extent of the competitive service. The competitive service shall include: (a) All... subject to the civil service laws by statute. OPM is authorized and directed to determine finally whether...

The role of sexual preferences in intrasexual female competition

PubMed Central

2012-01-01

Background While search costs have long been understood to affect the evolution of female preference, other costs associated with mating have been the focus of much less attention. Here I consider a novel mate choice cost: female-female intrasexual competition, that is, when females compete with each other for mates. This competition results in cost to female fecundity, such as a reduction in fertility due to decreased direct benefits, sperm limitation, or time and resources spent competing for a mate. I asked if female-female competition affects the evolution of preferences, and further, if the presence of multiple, different, preferences in a population can reduce competitive costs. Results Using population genetic models of preference and trait evolution, I found that intrasexual competition leads to direct selection against female preferences, and restricts the parameter space under which preference may evolve. I also examined how multiple, different, preferences affected preference evolution with female intrasexual competition. Conclusions Multiple preferences primarily serve to increase competitive costs and decrease the range of parameters under which preferences may evolve. PMID:23148567

Microbial competition between Bacillus subtilis and Staphylococcus aureus monitored by imaging mass spectrometry

PubMed Central

Gonzalez, David J.; Haste, Nina M.; Hollands, Andrew; Fleming, Tinya C.; Hamby, Matthew; Pogliano, Kit; Nizet, Victor

2011-01-01

Microbial competition exists in the general environment, such as soil or aquatic habitats, upon or within unicellular or multicellular eukaryotic life forms. The molecular actions that govern microbial competition, leading to niche establishment and microbial monopolization, remain undetermined. The emerging technology of imaging mass spectrometry (IMS) enabled the observation that there is directionality in the metabolic output of the organism Bacillus subtilis when co-cultured with Staphylococcus aureus. The directionally released antibiotic alters S. aureus virulence factor production and colonization. Therefore, IMS provides insight into the largely hidden nature of competitive microbial encounters and niche establishment, and provides a paradigm for future antibiotic discovery. PMID:21719540

Interaction between Gender and Skill on Competitive State Anxiety Using the Time-to-Event Paradigm: What Roles Do Intensity, Direction, and Frequency Dimensions Play?

PubMed Central

Hagan, John E.; Pollmann, Dietmar; Schack, Thomas

2017-01-01

Background and purpose: The functional understanding and examination of competitive anxiety responses as temporal events that unfold as time-to-competition moves closer has emerged as a topical research area within the domains of sport psychology. However, little is known from an inclusive and interaction oriented perspective. Using the multidimensional anxiety theory as a framework, the present study examined the temporal patterning of competitive anxiety, focusing on the dimensions of intensity, direction, and frequency of intrusions in athletes across gender and skill level. Methods: Elite and semi-elite table tennis athletes from the Ghanaian league (N = 90) completed a modified version of Competitive State Anxiety Inventory-2 (CSAI-2) with the inclusion of the directional and frequency of intrusion scales at three temporal phases (7 days, 2 days, and 1 h) prior to a competitive fixture. Results: Multivariate Analyses of Variance repeated measures with follow-up analyses revealed significant interactions for between-subjects factors on all anxiety dimensions (intensity, direction, and frequency). Notably, elite (international) female athletes were less cognitively anxious, showed more facilitative interpretation toward somatic anxiety symptoms and experienced less frequency of somatic anxiety symptoms than their male counterparts. However, both elite groups displayed appreciable level of self-confidence. For time-to-event effects, both cognitive and somatic anxiety intensity fluctuated whereas self-confidence showed a steady rise as competition neared. Somatic anxiety debilitative interpretation slightly improved 1 h before competition whereas cognitive anxiety frequencies also increased progressively during the entire preparatory phase. Conclusion: Findings suggest a more dynamic image of elite athletes’ pre-competitive anxiety responses than suggested by former studies, potentially influenced by cultural differences. The use of psychological skills interventions that require effective structure, content, and timing in a composite manner is suggested. PMID:28555116

Competitive Dynamics on Complex Networks

PubMed Central

Zhao, Jiuhua; Liu, Qipeng; Wang, Xiaofan

2014-01-01

We consider a dynamical network model in which two competitors have fixed and different states, and each normal agent adjusts its state according to a distributed consensus protocol. The state of each normal agent converges to a steady value which is a convex combination of the competitors' states, and is independent of the initial states of agents. This implies that the competition result is fully determined by the network structure and positions of competitors in the network. We compute an Influence Matrix (IM) in which each element characterizing the influence of an agent on another agent in the network. We use the IM to predict the bias of each normal agent and thus predict which competitor will win. Furthermore, we compare the IM criterion with seven node centrality measures to predict the winner. We find that the competitor with higher Katz Centrality in an undirected network or higher PageRank in a directed network is most likely to be the winner. These findings may shed new light on the role of network structure in competition and to what extent could competitors adjust network structure so as to win the competition. PMID:25068622

Inter-class competition in stage-structured populations: effects of adult density on life-history traits of adult and juvenile common lizards.

PubMed

San-Jose, Luis M; Peñalver-Alcázar, Miguel; Huyghe, Katleen; Breedveld, Merel C; Fitze, Patrick S

2016-12-01

Ecological and evolutionary processes in natural populations are largely influenced by the population's stage-structure. Commonly, different classes have different competitive abilities, e.g., due to differences in body size, suggesting that inter-class competition may be important and largely asymmetric. However, experimental evidence states that inter-class competition, which is important, is rare and restricted to marine fish. Here, we manipulated the adult density in six semi-natural populations of the European common lizard, Zootoca vivipara, while holding juvenile density constant. Adult density affected juveniles, but not adults, in line with inter-class competition. High adult density led to lower juvenile survival and growth before hibernation. In contrast, juvenile survival after hibernation was higher in populations with high adult density, pointing to relaxed inter-class competition. As a result, annual survival was not affected by adult density, showing that differences in pre- and post-hibernation survival balanced each other out. The intensity of inter-class competition affected reproduction, performance, and body size in juveniles. Path analyses unravelled direct treatment effects on early growth (pre-hibernation) and no direct treatment effects on the parameters measured after hibernation. This points to allometry of treatment-induced differences in early growth, and it suggests that inter-class competition mainly affects the early growth of the competitively inferior class and thereby their future performance and reproduction. These results are in contrast with previous findings and, together with results in marine fish, suggest that the strength and direction of density dependence may depend on the degree of inter-class competition, and thus on the availability of resources used by the competing classes.

77 FR 18309 - Patient Protection and Affordable Care Act; Establishment of Exchanges and Qualified Health Plans...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-27

...This final rule will implement the new Affordable Insurance Exchanges (``Exchanges''), consistent with title I of the Patient Protection and Affordable Care Act of 2010 as amended by the Health Care and Education Reconciliation Act of 2010, referred to collectively as the Affordable Care Act. The Exchanges will provide competitive marketplaces for individuals and small employers to directly compare available private health insurance options on the basis of price, quality, and other factors. The Exchanges, which will become operational by January 1, 2014, will help enhance competition in the health insurance market, improve choice of affordable health insurance, and give small businesses the same purchasing clout as large businesses.

A Comparative Analysis of Computer-Assisted Instruction and Traditional Lecture Instruction for Administration and Management Topics in Physical Therapy Education

ERIC Educational Resources Information Center

Hyland, Matthew R.; Pinto-Zipp, Genevieve; Olson, Valerie; Lichtman, Steven W.

2010-01-01

Technological advancements and competition in student recruitment have challenged educational institutions to expand upon traditional teaching methods in order to attract, engage and retain students. One strategy to meet this shift from educator-directed teaching to student-centered learning is greater computer utilization as an integral aspect of…

Some features of radiation processing in the plastics industry

NASA Astrophysics Data System (ADS)

D´, J.

In the last few years, the production of free radicals by radiation became competitive with chemical initiators. Nevertheless, radiation processing got only a firm footing, where distinct advantages could be demonstrated as compared with conventional processes, either in the technology or the product quality. This paper is intended to direct attention to some of the special features of radiation processing.

Intrasexual competition in females: evidence for sexual selection?

PubMed

Rosvall, Kimberly A

2011-11-01

In spite of recent interest in sexual selection in females, debate exists over whether traits that influence female-female competition are sexually selected. This review uses female-female aggressive behavior as a model behavioral trait for understanding the evolutionary mechanisms promoting intrasexual competition, focusing especially on sexual selection. I employ a broad definition of sexual selection, whereby traits that influence competition for mates are sexually selected, whereas those that directly influence fecundity or offspring survival are naturally selected. Drawing examples from across animal taxa, including humans, I examine 4 predictions about female intrasexual competition based on the abundance of resources, the availability of males, and the direct or indirect benefits those males provide. These patterns reveal a key sex difference in sexual selection: Although females may compete for the number of mates, they appear to compete more so for access to high-quality mates that provide direct and indirect (genetic) benefits. As is the case in males, intrasexual selection in females also includes competition for essential resources required for access to mates. If mate quality affects the magnitude of mating success, then restricting sexual selection to competition for quantity of mates may ignore important components of fitness in females and underestimate the role of sexual selection in shaping female phenotype. In the future, understanding sex differences in sexual selection will require further exploration of the extent of mutual intrasexual competition and the incorporation of quality of mating success into the study of sexual selection in both sexes.

Intrasexual competition in females: evidence for sexual selection?

PubMed Central

2011-01-01

In spite of recent interest in sexual selection in females, debate exists over whether traits that influence female–female competition are sexually selected. This review uses female–female aggressive behavior as a model behavioral trait for understanding the evolutionary mechanisms promoting intrasexual competition, focusing especially on sexual selection. I employ a broad definition of sexual selection, whereby traits that influence competition for mates are sexually selected, whereas those that directly influence fecundity or offspring survival are naturally selected. Drawing examples from across animal taxa, including humans, I examine 4 predictions about female intrasexual competition based on the abundance of resources, the availability of males, and the direct or indirect benefits those males provide. These patterns reveal a key sex difference in sexual selection: Although females may compete for the number of mates, they appear to compete more so for access to high-quality mates that provide direct and indirect (genetic) benefits. As is the case in males, intrasexual selection in females also includes competition for essential resources required for access to mates. If mate quality affects the magnitude of mating success, then restricting sexual selection to competition for quantity of mates may ignore important components of fitness in females and underestimate the role of sexual selection in shaping female phenotype. In the future, understanding sex differences in sexual selection will require further exploration of the extent of mutual intrasexual competition and the incorporation of quality of mating success into the study of sexual selection in both sexes. PMID:22479137

Interventions for obtaining and maintaining employment in adults with severe mental illness, a network meta-analysis.

PubMed

Suijkerbuijk, Yvonne B; Schaafsma, Frederieke G; van Mechelen, Joost C; Ojajärvi, Anneli; Corbière, Marc; Anema, Johannes R

2017-09-12

People with severe mental illness show high rates of unemployment and work disability, however, they often have a desire to participate in employment. People with severe mental illness used to be placed in sheltered employment or were enrolled in prevocational training to facilitate transition to a competitive job. Now, there are also interventions focusing on rapid search for a competitive job, with ongoing support to keep the job, known as supported employment. Recently, there has been a growing interest in combining supported employment with other prevocational or psychiatric interventions. To assess the comparative effectiveness of various types of vocational rehabilitation interventions and to rank these interventions according to their effectiveness to facilitate competitive employment in adults with severe mental illness. In November 2016 we searched CENTRAL, MEDLINE, Embase, PsychINFO, and CINAHL, and reference lists of articles for randomised controlled trials and systematic reviews. We identified systematic reviews from which to extract randomised controlled trials. We included randomised controlled trials and cluster-randomised controlled trials evaluating the effect of interventions on obtaining competitive employment for adults with severe mental illness. We included trials with competitive employment outcomes. The main intervention groups were prevocational training programmes, transitional employment interventions, supported employment, supported employment augmented with other specific interventions, and psychiatric care only. Two authors independently identified trials, performed data extraction, including adverse events, and assessed trial quality. We performed direct meta-analyses and a network meta-analysis including measurements of the surface under the cumulative ranking curve (SUCRA). We assessed the quality of the evidence for outcomes within the network meta-analysis according to GRADE. We included 48 randomised controlled trials involving 8743 participants. Of these, 30 studied supported employment, 13 augmented supported employment, 17 prevocational training, and 6 transitional employment. Psychiatric care only was the control condition in 13 studies. Direct comparison meta-analysis of obtaining competitive employmentWe could include 18 trials with short-term follow-up in a direct meta-analysis (N = 2291) of the following comparisons. Supported employment was more effective than prevocational training (RR 2.52, 95% CI 1.21 to 5.24) and transitional employment (RR 3.49, 95% CI 1.77 to 6.89) and prevocational training was more effective than psychiatric care only (RR 8.96, 95% CI 1.77 to 45.51) in obtaining competitive employment.For the long-term follow-up direct meta-analysis, we could include 22 trials (N = 5233). Augmented supported employment (RR 4.32, 95% CI 1.49 to 12.48), supported employment (RR 1.51, 95% CI 1.36 to 1.68) and prevocational training (RR 2.19, 95% CI 1.07 to 4.46) were more effective than psychiatric care only. Augmented supported employment was more effective than supported employment (RR 1.94, 95% CI 1.03 to 3.65), transitional employment (RR 2.45, 95% CI 1.69 to 3.55) and prevocational training (RR 5.42, 95% CI 1.08 to 27.11). Supported employment was more effective than transitional employment (RR 3.28, 95% CI 2.13 to 5.04) and prevocational training (RR 2.31, 95% CI 1.85 to 2.89). Network meta-analysis of obtaining competitive employmentWe could include 22 trials with long-term follow-up in a network meta-analysis.Augmented supported employment was the most effective intervention versus psychiatric care only in obtaining competitive employment (RR 3.81, 95% CI 1.99 to 7.31, SUCRA 98.5, moderate-quality evidence), followed by supported employment (RR 2.72 95% CI 1.55 to 4.76; SUCRA 76.5, low-quality evidence).Prevocational training (RR 1.26, 95% CI 0.73 to 2.19; SUCRA 40.3, very low-quality evidence) and transitional employment were not considerably different from psychiatric care only (RR 1.00,95% CI 0.51 to 1.96; SUCRA 17.2, low-quality evidence) in achieving competitive employment, but prevocational training stood out in the SUCRA value and rank.Augmented supported employment was slightly better than supported employment, but not significantly (RR 1.40, 95% CI 0.92 to 2.14). The SUCRA value and mean rank were higher for augmented supported employment.The results of the network meta-analysis of the intervention subgroups favoured augmented supported employment interventions, but also cognitive training. However, supported employment augmented with symptom-related skills training showed the best results (RR compared to psychiatric care only 3.61 with 95% CI 1.03 to 12.63, SUCRA 80.3).We graded the quality of the evidence of the network ranking as very low because of potential risk of bias in the included studies, inconsistency and publication bias. Direct meta-analysis of maintaining competitive employment Based on the direct meta-analysis of the short-term follow-up of maintaining employment, supported employment was more effective than: psychiatric care only, transitional employment, prevocational training, and augmented supported employment.In the long-term follow-up direct meta-analysis, augmented supported employment was more effective than prevocational training (MD 22.79 weeks, 95% CI 15.96 to 29.62) and supported employment (MD 10.09, 95% CI 0.32 to 19.85) in maintaining competitive employment. Participants receiving supported employment worked more weeks than those receiving transitional employment (MD 17.36, 95% CI 11.53 to 23.18) or prevocational training (MD 11.56, 95% CI 5.99 to 17.13).We did not find differences between interventions in the risk of dropouts or hospital admissions. Supported employment and augmented supported employment were the most effective interventions for people with severe mental illness in terms of obtaining and maintaining employment, based on both the direct comparison analysis and the network meta-analysis, without increasing the risk of adverse events. These results are based on moderate- to low-quality evidence, meaning that future studies with lower risk of bias could change these results. Augmented supported employment may be slightly more effective compared to supported employment alone. However, this difference was small, based on the direct comparison analysis, and further decreased with the network meta-analysis meaning that this difference should be interpreted cautiously. More studies on maintaining competitive employment are needed to get a better understanding of whether the costs and efforts are worthwhile in the long term for both the individual and society.

Estimating the Effect of Competition on Trait Evolution Using Maximum Likelihood Inference.

PubMed

Drury, Jonathan; Clavel, Julien; Manceau, Marc; Morlon, Hélène

2016-07-01

Many classical ecological and evolutionary theoretical frameworks posit that competition between species is an important selective force. For example, in adaptive radiations, resource competition between evolving lineages plays a role in driving phenotypic diversification and exploration of novel ecological space. Nevertheless, current models of trait evolution fit to phylogenies and comparative data sets are not designed to incorporate the effect of competition. The most advanced models in this direction are diversity-dependent models where evolutionary rates depend on lineage diversity. However, these models still treat changes in traits in one branch as independent of the value of traits on other branches, thus ignoring the effect of species similarity on trait evolution. Here, we consider a model where the evolutionary dynamics of traits involved in interspecific interactions are influenced by species similarity in trait values and where we can specify which lineages are in sympatry. We develop a maximum likelihood based approach to fit this model to combined phylogenetic and phenotypic data. Using simulations, we demonstrate that the approach accurately estimates the simulated parameter values across a broad range of parameter space. Additionally, we develop tools for specifying the biogeographic context in which trait evolution occurs. In order to compare models, we also apply these biogeographic methods to specify which lineages interact sympatrically for two diversity-dependent models. Finally, we fit these various models to morphological data from a classical adaptive radiation (Greater Antillean Anolis lizards). We show that models that account for competition and geography perform better than other models. The matching competition model is an important new tool for studying the influence of interspecific interactions, in particular competition, on phenotypic evolution. More generally, it constitutes a step toward a better integration of interspecific interactions in many ecological and evolutionary processes. © The Author(s) 2016. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Effects of reconstruction of a pre-European vertebrate assemblage on ground-dwelling arachnids in arid Australia.

PubMed

Silvey, Colin J; Hayward, Matthew W; Gibb, Heloise

2015-06-01

Species loss can result in changes in assemblage structure and ecosystem function through ecological cascades. Australian vertebrate assemblages changed significantly following European colonisation, which resulted in the establishment of invasive vertebrates and the loss of native marsupials, many of which consume invertebrates. Conservation focusses on the removal of invasive carnivores and the reintroduction of regionally extinct species to fenced sites, resulting in what could be considered a reconstruction of pre-European vertebrate assemblages. In semi-arid Australian spinifex mallee ecosystems, we asked: (1) what is the effect of reconstructed pre-European vertebrate assemblages on native arachnid assemblages? and (2) what direct or indirect mechanisms (predation, disturbance and/or competition) could plausibly be responsible for these effects? We compared sites with reconstructed vertebrate assemblages with paired control sites. Arachnids were sampled using pitfall trapping and direct searching. Hypotheses regarding mechanisms were tested using scat analysis (predation) and by comparing burrow depth (disturbance) and scorpion mass (competition) between control and reconstructed sites. The dominant dune scorpion, Urodacus yaschenkoi, was less abundant and a wolf spider (Lycosa gibsoni species group) more abundant in reconstructed sites. Differences in spider assemblage composition were marginally non-significant. Scat analysis confirmed native vertebrate predation on scorpions and we found no evidence that competition or disturbance affected scorpions. We, thus, suggest that changes in spider assemblages may have resulted from ecological cascades via decreases in dune scorpions. The loss of omnivorous mammals and other changes associated with the invasion of carnivores may, therefore, have had broad-reaching consequences for native arachnid assemblages in Australian ecosystems.

Effects of ultraviolet-B irradiance on intraspecific competition and facilitation of plants: self-thinning, size inequality, and phenotypic plasticity.

PubMed

Zhang, Rui-Chang; Lin, Yue; Yue, Ming; Li, Qian; Zhang, Xiao-Fei; Liu, Xiao; Chi, Hong; Chai, Yong-Fu; Wang, Mao

2012-01-01

(1) The effects of facilitation on the structure and dynamics of plant populations have not been studied so widely as competition. The UV-B radiation, as a typical environmental factor causing stress, may result in direct stress and facilitation. (2) The effects of UV-B radiation on intraspecific competition and facilitation were investigated based on the following three predictions on self-thinning, size inequality, and phenotypic plasticity: i) Self-thinning is the reduction in density that results from the increase in the mean biomass of individuals in crowded populations, and is driven by competition. In this study, the mortality rate of the population is predicted to decrease from UV-B irradiance. ii) The size inequality of a population increases with competition intensity because larger individuals receive a disproportionate share of resources, thereby leaving limited resources for smaller individuals. The second hypothesis assumes that direct stress decreases the size inequality of the population. iii) Phenotypic plasticity is the ability to alter one's morphology in response to environmental changes. The third hypothesis assumes that certain morphological indices can change among the trade-offs between competition, facilitation, and stress. These predictions were tested by conducting a field pot experiment using mung beans, and were supported by the following results: (3) UV-B radiation increased the survival rate of the population at the end of self-thinning. However, this result was mainly due to direct stress rather than facilitation. (4) Just as competitor, facilitation was also asymmetric. It increased the size inequality of populations during self-thinning, whereas stress decreased the size inequality. (5) Direct stress and facilitation influence plants differently on various scales. Stress inhibited plant growth, whereas facilitation showed the opposite on an individual scale. Stress increased survival rate, whereas facilitation increased individual variability on the population scale. (6) Trade-offs between competitions, facilitation, and direct stress varied in different growing stages.

Effects of Ultraviolet-B Irradiance on Intraspecific Competition and Facilitation of Plants: Self-Thinning, Size Inequality, and Phenotypic Plasticity

PubMed Central

Zhang, Rui-Chang; Lin, Yue; Yue, Ming; Li, Qian; Zhang, Xiao-Fei; Liu, Xiao; Chi, Hong; Chai, Yong-Fu; Wang, Mao

2012-01-01

(1) The effects of facilitation on the structure and dynamics of plant populations have not been studied so widely as competition. The UV-B radiation, as a typical environmental factor causing stress, may result in direct stress and facilitation. (2) The effects of UV-B radiation on intraspecific competition and facilitation were investigated based on the following three predictions on self-thinning, size inequality, and phenotypic plasticity: i) Self-thinning is the reduction in density that results from the increase in the mean biomass of individuals in crowded populations, and is driven by competition. In this study, the mortality rate of the population is predicted to decrease from UV-B irradiance. ii) The size inequality of a population increases with competition intensity because larger individuals receive a disproportionate share of resources, thereby leaving limited resources for smaller individuals. The second hypothesis assumes that direct stress decreases the size inequality of the population. iii) Phenotypic plasticity is the ability to alter one’s morphology in response to environmental changes. The third hypothesis assumes that certain morphological indices can change among the trade-offs between competition, facilitation, and stress. These predictions were tested by conducting a field pot experiment using mung beans, and were supported by the following results: (3) UV-B radiation increased the survival rate of the population at the end of self-thinning. However, this result was mainly due to direct stress rather than facilitation. (4) Just as competitor, facilitation was also asymmetric. It increased the size inequality of populations during self-thinning, whereas stress decreased the size inequality. (5) Direct stress and facilitation influence plants differently on various scales. Stress inhibited plant growth, whereas facilitation showed the opposite on an individual scale. Stress increased survival rate, whereas facilitation increased individual variability on the population scale. (6) Trade-offs between competitions, facilitation, and direct stress varied in different growing stages. PMID:23226393

Competition-Level Differences on the Lower Quarter Y-Balance Test in Baseball Players

PubMed Central

Butler, Robert J.; Bullock, Garrett; Arnold, Todd; Plisky, Phillip; Queen, Robin

2016-01-01

Context: Decreased performance in dynamic balance has previously been associated with a history of ulnar collateral ligament injury in baseball players. Previous research on dynamic balance in soccer players has shown that test performance depends on competition level. However, dynamic balance has yet to be examined in baseball players. Objective: To understand normative values and determine differences in dynamic balance, as measured by the Lower Quarter Y-Balance Test, across competition levels in baseball players. Design: Cross-sectional study. Setting: Preseason physical examinations. Patients or Other Participants: Dynamic balance was measured in 88 high school (HS), 78 collegiate (COL), and 90 professional (PRO) baseball players. Main Outcome Measure(s): All participants completed the Lower Quarter Y-Balance Test using the standard protocol. In unilateral stance, they reached with 1 foot in the anterior, posteromedial, and posterolateral directions. We calculated 1-way analyses of variance to compare performance, composite score, and reach asymmetry for each direction as well as the sum of the asymmetry values (P < .05). Composite score was calculated by averaging the maximum normalized reach scores. Reach asymmetry was determined by calculating bilateral differences in reach ability. Results: In comparison with the HS and COL groups, the PRO players exhibited greater posteromedial (P < .01; effect size index [ESI]HS = 1.06, ESICOL = 0.95) and posterolateral reach (P < .01; ESIHS = 0.82, ESICOL = 0.84) as well as a greater composite score (P < .01; ESIHS = 0.60, ESICOL = 0.87). In contrast, HS baseball players exhibited increased anterior reach (P < .01; ESICOL = 0.60, ESIPRO = 0.39) compared with the COL and PRO cohorts. No significant differences in reach asymmetry were observed among groups. Conclusions: Lower extremity dynamic balance performance differed based on the baseball players' competition level. These baseline data may be helpful in identifying low-performing athletes who might benefit from neuromuscular interventions. PMID:27849388

Competition-Level Differences on the Lower Quarter Y-Balance Test in Baseball Players.

PubMed

Butler, Robert J; Bullock, Garrett; Arnold, Todd; Plisky, Phillip; Queen, Robin

2016-12-01

Decreased performance in dynamic balance has previously been associated with a history of ulnar collateral ligament injury in baseball players. Previous research on dynamic balance in soccer players has shown that test performance depends on competition level. However, dynamic balance has yet to be examined in baseball players. To understand normative values and determine differences in dynamic balance, as measured by the Lower Quarter Y-Balance Test, across competition levels in baseball players. Cross-sectional study. Preseason physical examinations. Dynamic balance was measured in 88 high school (HS), 78 collegiate (COL), and 90 professional (PRO) baseball players. All participants completed the Lower Quarter Y-Balance Test using the standard protocol. In unilateral stance, they reached with 1 foot in the anterior, posteromedial, and posterolateral directions. We calculated 1-way analyses of variance to compare performance, composite score, and reach asymmetry for each direction as well as the sum of the asymmetry values (P < .05). Composite score was calculated by averaging the maximum normalized reach scores. Reach asymmetry was determined by calculating bilateral differences in reach ability. In comparison with the HS and COL groups, the PRO players exhibited greater posteromedial (P < .01; effect size index [ESI] HS = 1.06, ESI COL = 0.95) and posterolateral reach (P < .01; ESI HS = 0.82, ESI COL = 0.84) as well as a greater composite score (P < .01; ESI HS = 0.60, ESI COL = 0.87). In contrast, HS baseball players exhibited increased anterior reach (P < .01; ESI COL = 0.60, ESI PRO = 0.39) compared with the COL and PRO cohorts. No significant differences in reach asymmetry were observed among groups. Lower extremity dynamic balance performance differed based on the baseball players' competition level. These baseline data may be helpful in identifying low-performing athletes who might benefit from neuromuscular interventions.

Relative effects of harassment, frustration, and task characteristics on cardiovascular reactivity.

PubMed

García-León, Ana; Reyes del Paso, Gustavo A; Robles, Humbelina; Vila, Jaime

2003-02-01

Effects of anger induction procedures such as frustration and harassment on cardiovascular reactivity have been demonstrated in a wide range of experimental situations. Similarly, heightened cardiovascular reactivity has been associated with a diverse range of tasks involving active coping, competition and interpersonal interaction. The present study sought to directly compare the relative effects of these two important ways of inducing cardiovascular changes. One hundred and five university students performed two tasks that differed in the degree of active coping and interpersonal competition: a competitive psychomotor task and a problem-solving task. States of anger were induced during both tasks by means of harassment, frustration or frustration+harassment. Task-related changes in heart rate, systolic blood pressure, diastolic blood pressure, pulse volume amplitude and respiratory sinus arrhythmia amplitude were monitored. The competitive psychomotor task produced greater cardiovascular reactivity than did the problem-solving task. Harassment and frustration+harassment provoked more cardiovascular reactivity than did frustration alone. However, harassment and frustration+harassment had the greatest cardiovascular effects in the competitive task, whereas frustration had the greatest cardiovascular effects in the problem-solving task. In this sense, the increases on cardiovascular reactivity seem to depend on the interaction between anger induction procedures and the context in which anger is provoked.

Competitive effects of fire-resistant saplings on their fire-sensitive neighbors are greater than the reverse

Treesearch

J. Stephen Brewer

2015-01-01

Although repeated fires are generally thought to reduce competition, direct tests of this hypothesis are rare. Furthermore, recent theory predicts that fires can increase competitive effects of fireresistant species on fire-sensitive species and thus create stable assemblages dominated by the former. In this study, I quantified competition between saplings of fire-...

Female competition and aggression: interdisciplinary perspectives

PubMed Central

Stockley, Paula; Campbell, Anne

2013-01-01

This paper introduces a Theme Issue combining interdisciplinary perspectives in the study of female competition and aggression. Despite a history of being largely overlooked, evidence is now accumulating for the widespread evolutionary significance of female competition. Here, we provide a synthesis of contributions to this Theme Issue on humans and other vertebrates, and highlight directions for future research. Females compete for resources needed to survive and reproduce, and for preferred mates. Although female aggression takes diverse forms, under most circumstances relatively low-risk competitive strategies are favoured, most probably due to constraints of offspring production and care. In social species, dominance relationships and threats of punishment can resolve social conflict without resort to direct aggression, and coalitions or alliances may reduce risk of retaliation. Consistent with these trends, indirect aggression is a low cost but effective form of competition among young women. Costs are also minimized by flexibility in expression of competitive traits, with aggressive behaviour and competitive signalling tailored to social and ecological conditions. Future research on female competition and the proximate mediators of female aggression will be greatly enhanced by opportunities for interdisciplinary exchange, as evidenced by contributions to this Theme Issue. PMID:24167303

76 FR 77555 - Notice of Determinations Regarding Eligibility To Apply for Worker Adjustment Assistance

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2011-12-13

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78 FR 52978 - Notice of Determinations Regarding Eligibility to Apply for Worker Adjustment Assistance

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2013-08-27

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2012-04-02

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76 FR 40402 - Matthews International Corporation, Bronze Division, Kingwood, WV; Notice of Negative...

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2011-07-08

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76 FR 35478 - Notice of Determinations Regarding Eligibility To Apply for Worker Adjustment Assistance

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2011-06-17

... absolutely; and (3) One of the following must be satisfied: (A) Imports of articles or services like or directly competitive with articles produced or services supplied by such firm have increased; (B) Imports of articles like or directly competitive with articles into which one or more component parts...

How chimpanzees cooperate in a competitive world

PubMed Central

Suchak, Malini; Eppley, Timothy M.; Campbell, Matthew W.; Feldman, Rebecca A.; Quarles, Luke F.; de Waal, Frans B. M.

2016-01-01

Our species is routinely depicted as unique in its ability to achieve cooperation, whereas our closest relative, the chimpanzee (Pan troglodytes), is often characterized as overly competitive. Human cooperation is assisted by the cost attached to competitive tendencies through enforcement mechanisms, such as punishment and partner choice. To examine if chimpanzees possess the same ability to mitigate competition, we set up a cooperative task in the presence of the entire group of 11 adults, which required two or three individuals to pull jointly to receive rewards. This open-group set-up provided ample opportunity for competition (e.g., freeloading, displacements) and aggression. Despite this unique set-up and initial competitiveness, cooperation prevailed in the end, being at least five times as common as competition. The chimpanzees performed 3,565 cooperative acts while using a variety of enforcement mechanisms to overcome competition and freeloading, as measured by (attempted) thefts of rewards. These mechanisms included direct protest by the target, third-party punishment in which dominant individuals intervened against freeloaders, and partner choice. There was a marked difference between freeloading and displacement; freeloading tended to elicit withdrawal and third-party interventions, whereas displacements were met with a higher rate of direct retaliation. Humans have shown similar responses in controlled experiments, suggesting shared mechanisms across the primates to mitigate competition for the sake of cooperation. PMID:27551075

75 FR 9523 - New Postal Product

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2010-03-03

... adding Global Direct Contracts 1 to the Competitive Product List. This action is consistent with a postal reform law. Republication of the lists of market dominant and competitive products is also consistent... Competitive Product List. For the reasons discussed below, the Commission approves the Request. II. Background...

Diversity begets diversity in competition for space

Treesearch

Daniel S. Maynard; Mark A. Bradford; Daniel L. Lindner; Linda T. A. van Diepen; Serita D. Frey; Jessie A. Glaeser; Thomas W. Crowther

2017-01-01

Competition can profoundly affect biodiversity patterns by determining whether similar species are likely to coexist. When species compete directly for space, competitive ability differences should theoretically promote trait and phylogenetic clustering, provided that niche differences are otherwise minimal. Yet many sessile communities exhibit high biodiversity...

Quantifying the balance between bycatch and predator or competitor release for nontarget species.

PubMed

Aalto, Emilius A; Baskett, Marissa L

2013-07-01

If a species is bycatch in a fishery targeted at its competitor or predator, it experiences both direct anthropogenic mortality and indirect positive effects through species interactions. If the species involved interact strongly, the release from competition or predation can counteract or exceed the negative effects of bycatch. We used a set of two- and three-species community modules to analyze the relative importance of species interactions when modeling the overall effect of harvest with bycatch on a nontarget species. To measure the trade-off between direct mortality and indirect positive effects, we developed a "bycatch transition point" metric to determine, for different scenarios, what levels of bycatch shift overall harvest impact from positive to negative. Under strong direct competition with a targeted competitor, release from competition due to harvest leads to a net increase in abundance even under moderate levels of bycatch. For a three-species model with a shared obligate predator, the release from apparent competition exceeds direct competitive release and outweighs the decrease from bycatch mortality under a wide range of parameters. Therefore, in communities where a shared predator forms a strong link between the target and nontarget species, the effects of indirect interactions on populations can be larger than those of direct interactions. The bycatch transition point metric can be used for tightly linked species to evaluate the relative strengths of positive indirect effects and negative anthropogenic impacts such as bycatch, habitat degradation, and introduction of invasive species.

Competitive strategy for providers.

PubMed

Hackett, M C

1996-01-01

National Health Service (NHS) Trusts are struggling to determine a long-term strategic direction for their organizations in response to the competitive pressures generated by the NHS reforms. The development of long-term strategic direction and the methods to implement this are presenting real challenges to the Trusts which have inherited service configurations based on bureaucratic planning frameworks rather than service configurations suited to a more competitive environment. Examines the strategic choices available to these organizations; explores the importance of identifying positive strategic choices; and discusses the advantages and disadvantages in the context of the NHS internal market.

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... (direct) sale to the town of Ten Sleep under the provisions of the Federal Land Policy and Management Act... reservation of a right-of-way for a Federal-aid Highway (Ten Sleep-Big Trails Road) as to lot 10, sec. 21, T... direct sale to the Town of Ten Sleep pursuant to 43 CFR 2711.3-3. A competitive sale is not appropriate...

Intramural Gymnastics Competition.

ERIC Educational Resources Information Center

Cornelius, William L.

1981-01-01

An intramural gymnastic competition, if properly organized, can foster student and community interest in gymnastics. Aspects of organization and essential preplanning include: directing, judging, scoring, and managing. (JN)

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Rural Policy in a New Century.

ERIC Educational Resources Information Center

Marshall, Ray

Past rural policies are reviewed, noting the effects of globalization and information technology. Rural business profits can be maximized by direct cost or value-added competition, but cost competition limits the development of productive capacity and leads to unequal income distribution. In contrast, value-added competition could create steep…

Patient Protection and Affordable Care Act; establishment of exchanges and qualified health plans; exchange standards for employers. Final rule, Interim final rule.

PubMed

2012-03-27

This final rule will implement the new Affordable Insurance Exchanges ("Exchanges"), consistent with title I of the Patient Protection and Affordable Care Act of 2010 as amended by the Health Care and Education Reconciliation Act of 2010, referred to collectively as the Affordable Care Act. The Exchanges will provide competitive marketplaces for individuals and small employers to directly compare available private health insurance options on the basis of price, quality, and other factors. The Exchanges, which will become operational by January 1, 2014, will help enhance competition in the health insurance market, improve choice of affordable health insurance, and give small businesses the same purchasing clout as large businesses.

Mutualism supports biodiversity when the direct competition is weak

PubMed Central

Pascual-García, Alberto; Bastolla, Ugo

2017-01-01

A key question of theoretical ecology is which properties of ecosystems favour their stability and help maintaining biodiversity. This question recently reconsidered mutualistic systems, generating intense controversy about the role of mutualistic interactions and their network architecture. Here we show analytically and verify with simulations that reducing the effective interspecific competition and the propagation of perturbations positively influences structural stability against environmental perturbations, enhancing persistence. Noteworthy, mutualism reduces the effective interspecific competition only when the direct interspecific competition is weaker than a critical value. This critical competition is in almost all cases larger in pollinator networks than in random networks with the same connectance. Highly connected mutualistic networks reduce the propagation of environmental perturbations, a mechanism reminiscent of MacArthur’s proposal that ecosystem complexity enhances stability. Our analytic framework rationalizes previous contradictory results, and it gives valuable insight on the complex relationship between mutualism and biodiversity. PMID:28232740

A serious game skills competition increases voluntary usage and proficiency of a virtual reality laparoscopic simulator during first-year surgical residents' simulation curriculum.

PubMed

El-Beheiry, Mostafa; McCreery, Greig; Schlachta, Christopher M

2017-04-01

The objective of this study was to assess the effect of a serious game skills competition on voluntary usage of a laparoscopic simulator among first-year surgical residents' standard simulation curriculum. With research ethics board approval, informed consent was obtained from first-year surgical residents enrolled in an introductory surgical simulation curriculum. The class of 2013 served as a control cohort following the standard curriculum which mandates completion of six laparoscopic simulator skill tasks. For the 2014 competition cohort, the only change introduced was the biweekly and monthly posting of a leader board of the top three and ten fastest peg transfer times. Entry surveys were administered assessing attitudes towards simulation-based training and competition. Cohorts were observed for 5 months. There were 24 and 25 residents in the control and competition cohorts, respectively. The competition cohort overwhelmingly (76 %) stated that they were not motivated to deliberate practice by competition. Median total simulator usage time was 132 min (IQR = 214) in the competition cohort compared to 89 (IQR = 170) in the control cohort. The competition cohort completed their course requirements significantly earlier than the control cohort (χ 2  = 6.5, p = 0.01). There was a significantly greater proportion of residents continuing to use the simulator voluntarily after completing their course requirements in the competition cohort (44 vs. 4 %; p = 0.002). Residents in the competition cohort were significantly faster at peg transfer (194 ± 66 vs. 233 ± 53 s, 95 % CI of difference = 4-74 s; p = 0.03) and significantly decreased their completion time by 33 ± 54 s (95 % CI 10-56 s; paired t test, p = 0.007). A simple serious games skills competition increased voluntary usage and performance on a laparoscopic simulator, despite a majority of participants reporting they were not motivated by competition. Future directions should endeavour to examine other serious gaming modalities to further engage trainees in simulated skills development.

Characterization of monoclonal antibodies directed against the bovine herpesvirus-1 glycoprotein E and use for the differentiation between vaccinated and infected animals.

PubMed

Letellier, C; Delangre, A; De Smet, A; Kerkhofs, P

2001-12-04

A panel of seven monoclonal antibodies (MAbs) directed against the bovine herpesvirus-1 (BHV-1) glycoprotein E (gE) was obtained. For that purpose, mice were either tolerized to BHV-1 gE-negative virus and then immunized with wild type BHV-1 or immunized with plasmid DNA expressing the gE and gI glycoproteins. The MAbs were characterized by their reactivity with the gE protein or the gE/gI complex and by competition experiments. Results showed that the MAbs were directed against three antigenic domains, two located on the gE glycoprotein and one on the gE/gI complex. Blocking experiments were performed with sera from experimentally vaccinated and infected cattle. A competition was observed between gE-positive bovine sera and six of the seven MAbs. The bovine sera thus recognized two of the three antigenic sites. Field sera were then tested in blocking enzyme-linked immunosorbent assay using one horseradish peroxidase-conjugated MAb. A specificity of 98.2% and a sensitivity of 98.2% compared to the commercially available test were observed.

EFL Learners' Use of Direct Strategies in Competitive and Cooperative Learning Contexts

ERIC Educational Resources Information Center

Zarei, Abbas Ali; Layeq, Hamide

2016-01-01

This study investigated the effects of competitive and cooperative teaching techniques on Iranian adult EFL learners' use of direct strategies. To this end, a sample of 88 non-English major university students at Sohrevardi Nonprofit College in Qazvin were assigned to two groups, and each group received instruction under one of the treatment…

Direct and indirect effects of a dense understory on tree seedling recruitment in temperate forests: habitat-mediated predation versus competition

Treesearch

Alejandro A. Royo; Walter P. Carson

2008-01-01

In forests characterized by a dense woody and herbaceous understory layer, seedling recruitment is often directly suppressed via interspecific competition. Alternatively, these dense layers may indirectly lower tree recruitment by providing a haven for seed and seedling predators that prey on neighboring plant species. To simultaneously...

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2010-09-15

... firm have decreased absolutely; and (3) One of the following must be satisfied: (A) Imports of articles.../services that are like or directly competitive with those produced/supplied by the workers' firm; and (3... services like or directly competitive with services which are supplied by such agency; and (3) The...

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2011-02-14

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2011-08-18

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2010-07-02

... DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLIDI01000-L143000000.EU0000; IDI-19600-03] Notice of Realty Action: Non-Competitive (Direct) Sale of Public Lands and Termination of a Recreation and Public Purposes Act Classification, Madison County, ID AGENCY: Bureau of Land Management, Interior...

78 FR 68061 - Wireline Competition Bureau Seeks Comment on the Lifeline Biennial Audit Plan

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-13

... Bureau), in conjunction with the Office of Managing Director (OMD), seeks to develop standard procedures..., directed the Wireline Competition Bureau (WCB), in conjunction with the Office of Managing Director (OMD... 5. The Wireline Competition Bureau (Bureau), in conjunction with the Office of Managing Director...

43 CFR 13.5 - Protection from competition.

Code of Federal Regulations, 2012 CFR

2012-10-01

... BLIND PERSONS § 13.5 Protection from competition. (a) The head of the Interior bureau or office shall protect the blind operator of the vending facility against direct competition from other vendors or... expense of their operators to locations elsewhere on the property which are noncompetitive with a blind...

43 CFR 13.5 - Protection from competition.

Code of Federal Regulations, 2013 CFR

2013-10-01

... BLIND PERSONS § 13.5 Protection from competition. (a) The head of the Interior bureau or office shall protect the blind operator of the vending facility against direct competition from other vendors or... expense of their operators to locations elsewhere on the property which are noncompetitive with a blind...

43 CFR 13.5 - Protection from competition.

Code of Federal Regulations, 2014 CFR

2014-10-01

... BLIND PERSONS § 13.5 Protection from competition. (a) The head of the Interior bureau or office shall protect the blind operator of the vending facility against direct competition from other vendors or... expense of their operators to locations elsewhere on the property which are noncompetitive with a blind...

Determinats of Interregional Competion of Subjects of Russian Federation

NASA Astrophysics Data System (ADS)

Gaisin, R. I.; Latypov, R. A.; Gaisin, I. T.; Kubyshkina, E. N.; Hayaleeva, A. D.

2018-05-01

In the article, problems of the analysis of competitiveness of subjects of the Russian Federation at the level of the national market of the country are considered. For a research of indicators and dynamics of competitiveness of certain territorial subjects of the Russian Federation, the methodology and tools of the theory of the interregional markets of the country developed by one of authors of epy article are used. On the basis of the known theory of competitiveness of M. Porter, the main directions of an increase of the competition in the interregional market of Russia are offered. Keywords: competitiveness, competitiveness determinants, interregional competition, interregional markets of the country

Pre and Post-copulatory Selection Favor Similar Genital Phenotypes in the Male Broad Horned Beetle.

PubMed

House, Clarissa M; Sharma, M D; Okada, Kensuke; Hosken, David J

2016-10-01

Sexual selection can operate before and after copulation and the same or different trait(s) can be targeted during these episodes of selection. The direction and form of sexual selection imposed on characters prior to mating has been relatively well described, but the same is not true after copulation. In general, when male-male competition and female choice favor the same traits then there is the expectation of reinforcing selection on male sexual traits that improve competitiveness before and after copulation. However, when male-male competition overrides pre-copulatory choice then the opposite could be true. With respect to studies of selection on genitalia there is good evidence that male genital morphology influences mating and fertilization success. However, whether genital morphology affects reproductive success in more than one context (i.e., mating versus fertilization success) is largely unknown. Here we use multivariate analysis to estimate linear and nonlinear selection on male body size and genital morphology in the flour beetle Gnatocerus cornutus, simulated in a non-competitive (i.e., monogamous) setting. This analysis estimates the form of selection on multiple traits and typically, linear (directional) selection is easiest to detect, while nonlinear selection is more complex and can be stabilizing, disruptive, or correlational. We find that mating generates stabilizing selection on male body size and genitalia, and fertilization causes a blend of directional and stabilizing selection. Differences in the form of selection across these bouts of selection result from a significant alteration of nonlinear selection on body size and a marginally significant difference in nonlinear selection on a component of genital shape. This suggests that both bouts of selection favor similar genital phenotypes, whereas the strong stabilizing selection imposed on male body size during mate acquisition is weak during fertilization. © The Author 2016. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology.

Land inheritance establishes sibling competition for marriage and reproduction in rural Ethiopia

PubMed Central

Gibson, Mhairi A.; Gurmu, Eshetu

2011-01-01

Intergenerational transfer of wealth has been proposed as playing a pivotal role in the evolution of human sibling relationships. Sibling rivalry is assumed to be more marked when offspring compete for limited heritable resources, which are crucial for reproductive success (e.g., land and livestock); whereas in the absence of heritable wealth, related siblings may cooperate. To date, comparative studies undertaken to support this evolutionary assumption have been confounded by other socioecological factors, which vary across populations, e.g., food sharing and intergroup conflict. In this article we explore effects of sibling competition and cooperation for agricultural resources, marriage, and reproduction in one contemporary Ethiopian agropastoralist society. Here recent changes in land tenure policy, altering transfers of land from parents to offspring, present a unique framework to test the importance of intergenerational transfers of wealth in driving sibling competition, while controlling for socioeconomic biases. In households where land is inherited, the number of elder brothers reduces a man's agricultural productivity, marriage, and reproductive success, as resources diminish and competition increases with each additional sibling. Where land is not inherited (for males receiving land directly from the government and all females) older siblings do not have a competitive effect and in some instances may be beneficial. This study has wider implications for the evolution of human family sizes. Recent changes in wealth transfers, which have driven sibling competition, may be contributing to an increased desire for smaller family sizes. PMID:21262826

Land inheritance establishes sibling competition for marriage and reproduction in rural Ethiopia.

PubMed

Gibson, Mhairi A; Gurmu, Eshetu

2011-02-08

Intergenerational transfer of wealth has been proposed as playing a pivotal role in the evolution of human sibling relationships. Sibling rivalry is assumed to be more marked when offspring compete for limited heritable resources, which are crucial for reproductive success (e.g., land and livestock); whereas in the absence of heritable wealth, related siblings may cooperate. To date, comparative studies undertaken to support this evolutionary assumption have been confounded by other socioecological factors, which vary across populations, e.g., food sharing and intergroup conflict. In this article we explore effects of sibling competition and cooperation for agricultural resources, marriage, and reproduction in one contemporary Ethiopian agropastoralist society. Here recent changes in land tenure policy, altering transfers of land from parents to offspring, present a unique framework to test the importance of intergenerational transfers of wealth in driving sibling competition, while controlling for socioeconomic biases. In households where land is inherited, the number of elder brothers reduces a man's agricultural productivity, marriage, and reproductive success, as resources diminish and competition increases with each additional sibling. Where land is not inherited (for males receiving land directly from the government and all females) older siblings do not have a competitive effect and in some instances may be beneficial. This study has wider implications for the evolution of human family sizes. Recent changes in wealth transfers, which have driven sibling competition, may be contributing to an increased desire for smaller family sizes.

Ablative heat shield design for space shuttle

NASA Technical Reports Server (NTRS)

Seiferth, R. W.

1973-01-01

Ablator heat shield configuration optimization studies were conducted for the orbiter. Ablator and reusable surface insulation (RSI) trajectories for design studies were shaped to take advantage of the low conductance of ceramic RSI and high temperature capability of ablators. Comparative weights were established for the RSI system and for direct bond and mechanically attached ablator systems. Ablator system costs were determined for fabrication, installation and refurbishment. Cost penalties were assigned for payload weight penalties, if any. The direct bond ablator is lowest in weight and cost. A mechanically attached ablator using a magnesium subpanel is highly competitive for both weight and cost.

Turboprop cargo aircraft systems study

NASA Technical Reports Server (NTRS)

Muehlbauer, J. C.; Hewell, J. G., Jr.; Lindenbaum, S. P.; Randall, C. C.; Searle, N.; Stone, R. G., Jr.

1981-01-01

The effects of using advanced turboprop propulsion systems to reduce the fuel consumption and direct operating costs of cargo aircraft were studied, and the impact of these systems on aircraft noise and noise prints around a terminal area was determined. Parametric variations of aircraft and propeller characteristics were investigated to determine their effects on noiseprint areas, fuel consumption, and direct operating costs. From these results, three aircraft designs were selected and subjected to design refinements and sensitivity analyses. Three competitive turbofan aircraft were also defined from parametric studies to provide a basis for comparing the two types of propulsion.

Health care competition, strategic mission, and patient satisfaction: research model and propositions.

PubMed

Rivers, Patrick A; Glover, Saundra H

2008-01-01

In all industries, competition among businesses has long been encouraged as a mechanism to increase value for patients. In other words, competition ensures the provision of better products and services to satisfy the needs of customers This paper aims to develop a model that can be used to empirically investigate a number of complex issues and relationships associated with competition in the health care industry. A literature review was conducted. A total of 50 items of literature related to the subject were reviewed. Various perspectives of competition, the nature of service quality, health system costs, and patient satisfaction in health care are examined. A model of the relationship among these variables is developed. The model depicts patient satisfaction as an outcome measure directly dependent on competition. Quality of care and health care systems costs, while also directly dependent on the strategic mission and goals, are considered as determinants of customer satisfaction as well. The model is discussed in the light of propositions for empirical research. Empirical studies based on the model proposed in this paper should help identify areas with significant impact on patient satisfaction while maintaining high quality of service at lower costs in a competitive environment. The authors develop a research model which included propositions to examine the complex issues of competition in the health care industry.

Development of analytical method for ultrasensitive detection of salbutamol utilizing DNA labeled-immunoprobe.

PubMed

Lei, Yajing; Li, Xiaoyi; Akash, Muhammad Sajid Hamid; Zhou, Lifang; Tang, Xiaojing; Shi, Weixing; Liu, Zhiming; Chen, Shuqing

2015-03-25

Salbutamol (SAL) is known as quick-acting β-2 receptor agonist and its use in humans for pulmonary diseases and/or in animal feed is limited because of associated potential hazardous effects on health. Several techniques are available for the detection of SAL, but are expensive and time consuming. Here for the first time, a novel pre-assembled DNA immunoprobe-based immuno-PCR assay was developed to investigate the levels of SAL in human urine samples and compared the proposed immuno-PCR assay for the detection of SAL with that of direct competitive ELISA. Under the optimized conditions, the assay showed a linear range over seven orders of magnitude, whereas the limit of detection of SAL in buffer was found to be 21 fg/mL. Current immuno-PCR assay exhibited a 300-fold better detection limit for SAL as compared to one achieved with direct competitive ELISA using the same antibody. In conclusion, it has been found that the developed method is highly sensitive and simple method that can significantly enhance the detection sensitivity for small molecules. Moreover it can be modified and used for detecting other small molecules and/or chemicals that exist in the environment and are responsible for the environmental pollution. Copyright © 2014 Elsevier B.V. All rights reserved.

Direct and indirect effects of climate change on a prairie plant community.

PubMed

Adler, Peter B; Leiker, James; Levine, Jonathan M

2009-09-03

Climate change directly affects species by altering their physical environment and indirectly affects species by altering interspecific interactions such as predation and competition. Recent studies have shown that the indirect effects of climate change may amplify or counteract the direct effects. However, little is known about the the relative strength of direct and indirect effects or their potential to impact population persistence. We studied the effects of altered precipitation and interspecific interactions on the low-density tiller growth rates and biomass production of three perennial grass species in a Kansas, USA mixed prairie. We transplanted plugs of each species into local neighborhoods of heterospecific competitors and then exposed the plugs to a factorial manipulation of growing season precipitation and neighbor removal. Precipitation treatments had significant direct effects on two of the three species. Interspecific competition also had strong effects, reducing low-density tiller growth rates and aboveground biomass production for all three species. In fact, in the presence of competitors, (log) tiller growth rates were close to or below zero for all three species. However, we found no convincing evidence that per capita competitive effects changed with precipitation, as shown by a lack of significant precipitation x competition interactions. We found little evidence that altered precipitation will influence per capita competitive effects. However, based on species' very low growth rates in the presence of competitors in some precipitation treatments, interspecific interactions appear strong enough to affect the balance between population persistence and local extinction. Therefore, ecological forecasting models should include the effect of interspecific interactions on population growth, even if such interaction coefficients are treated as constants.

Strategic Plan: Initiating an Orthopaedic Residency at Womack Army Medical Center

DTIC Science & Technology

2006-06-07

outlining WAMC’s strategy: analysis of Porter’s Five Forces Model; a Strategic Map for discovering competitive advantages and disadvantages ; identifying a...Figure 6. Strategic Map of Advantages and Disadvantages ............................... 27 Figure 7. Directional Strategy...analysis; analysis of Porter’s Five Forces Model; a strategic map for discovering competitive advantages and disadvantages ; identifying a directional

Moral Attitudes Predict Cheating and Gamesmanship Behaviors Among Competitive Tennis Players

PubMed Central

Lucidi, Fabio; Zelli, Arnaldo; Mallia, Luca; Nicolais, Giampaolo; Lazuras, Lambros; Hagger, Martin S.

2017-01-01

Background: The present study tested Lee et al.’s (2008) model of moral attitudes and cheating behavior in sports in an Italian sample of young tennis players and extended it to predict behavior in actual match play. In the first phase of the study we proposed that moral, competence and status values would predict prosocial and antisocial moral attitudes directly, and indirectly through athletes’ goal orientations. In the second phase, we hypothesized that moral attitudes would directly predict actual cheating behavior observed during match play. Method: Adolescent competitive tennis players (N = 314, 76.75% males, M age = 14.36 years, SD = 1.50) completed measures of values, goal orientations, and moral attitudes. A sub-sample (n = 90) was observed in 45 competitive tennis matches by trained observers who recorded their cheating and gamesmanship behaviors on a validated checklist. Results: Consistent with hypotheses, athletes’ values predicted their moral attitudes through the effects of goal orientations. Anti-social attitudes directly predicted cheating behavior in actual match play providing support for a direct link between moral attitude and actual behavior. Conclusion: The present study findings support key propositions of Lee and colleagues’ model, and extended its application to competitive athletes in actual match play. PMID:28446891

The importance of ecological costs for the evolution of plant defense against herbivory.

PubMed

van Velzen, Ellen; Etienne, Rampal S

2015-05-07

Plant defense against herbivory comes at a cost, which can be either direct (reducing resources available for growth and reproduction) or indirect (through reducing ecological performance, for example intraspecific competitiveness). While direct costs have been well studied in theoretical models, ecological costs have received almost no attention. In this study we compare models with a direct trade-off (reduced growth rate) to models with an ecological trade-off (reduced competitive ability), using a combination of adaptive dynamics and simulations. In addition, we study the dependence of the level of defense that can evolve on the type of defense (directly by reducing consumption, or indirectly by inducing herbivore mortality (toxicity)), and on the type of herbivore against which the plant is defending itself (generalists or specialists). We find three major results: First, for both direct and ecological costs, defense only evolves if the benefit to the plant is direct (through reducing consumption). Second, the type of cost has a major effect on the evolutionary dynamics: direct costs always lead to a single optimal strategy against herbivores, but ecological costs can lead to branching and the coexistence of non-defending and defending plants; however, coexistence is only possible when defending against generalist herbivores. Finally, we find that fast-growing plants invest less than slow-growing plants when defending against generalist herbivores, as predicted by the Resource Availability Hypothesis, but invest more than slow-growing plants when defending against specialists. Our results clearly show that assumptions about ecological interactions are crucial for understanding the evolution of defense against herbivores. Copyright © 2015 Elsevier Ltd. All rights reserved.

Seated limits-of-stability of athletes with disabilities with regard to competitive levels and sport classification.

PubMed

Santos, P B R; Vigário, P S; Mainenti, M R M; Ferreira, A S; Lemos, T

2017-12-01

In this study, we asked whether wheelchair rugby (WR) classification and competitive level influence trunk function of athletes with disabilities, in terms of seated limits-of-stability (LoS). Twenty-eight athletes were recruited from international- and national-level WR teams, with each group exhibiting marked differences in years of sports practice and training volume. Athletes were also distributed into three groups according their classification: low-point (0.5-1.5-point); mid-point (2.0-2.5-point); and high-point (3.0-3.5-point). Athletes were asked to sit on a force platform and to lean the body as far as possible in eight predefined directions. Center of pressure (COP) coordinates were calculated from the ground reaction forces acquired with the force platform. LoS were computed as the area of ellipse adjusted to maximal COP excursion achieved for the eight directions. ANOVAs reveal that LoS were not different when international- and national-level players were compared (P=.744). Nevertheless, LoS were larger in players from the high-point group than from the low-point group (P=.028), with the mid-point group being not different from both (P>.194). In summary, (i) competitive level does not impact LoS measures and (ii) LoS are remarkably distinct when comparing both extremes of the WR classification range. Our results suggest that, as a training-resistant measure, LoS could be a valid assessment of trunk impairment, potentially contributing to the development of an evidence-based WR classification. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Assessing Preschool Children's Competitive Behaviour: An Observational System

ERIC Educational Resources Information Center

Tsiakara, Angeliki; Digelidis, Nikolaos M.

2014-01-01

The aim of this study was to develop a direct observational system in order to assess competitive behaviours in preschool children. Participants were 176 children (90 boys, 86 girls; M[subscript age]?=?5.2 years) from 10 kindergarten classes of one town of Central Greece. A new observational system (Observational System Assessing Competition in…

75 FR 63237 - Self-Regulatory Organizations; EDGA Exchange, Inc.; Notice of Filing and Immediate Effectiveness...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-14

... proposed rule change reflects a competitive pricing structure designed to incent market participants to... these rate changes will enable it to maintain a competitive position with regards to other away market... notes that it operates in a highly competitive market in which market participants can readily direct...

Competition and the Performance of English Secondary Schools: Further Evidence

ERIC Educational Resources Information Center

Levacic, Rosalind

2004-01-01

Both advocates of competition as a means to better school performance and economics-based research on this issue assume a direct relationship between a more competitive market structure (in terms of the number and concentration of schools in a local market) and better school performance. This is an application to schools of the…

A cluster analysis of perfectionism among competitive athletes.

PubMed

Martinent, Guillaume; Ferrand, Claude

2006-12-01

In the present study, the ways in which athletes may experience perfectionism in a sport context were examined. The question of interest was whether self-confidence, intensity, and direction of cognitive and somatic precompetitive anxiety would differ across identifiable profiles of perfectionism. Competitive athletes (N= 166) completed the Sport-Multidimensional Perfectionism Scale, the French-Canadian Hewitt Multidimensional Perfectionism Scale, and the Competitive State Anxiety Inventory-2 Revised, including a Direction scale. Results of the cluster analysis indicated that athletes could be classified into three groups labelled Nonperfectionists, Adaptive perfectionists, and Maladaptive perfectionists. Perfectionism profiles differed significantly on Cognitive and Somatic Anxiety Intensity and on Cognitive Anxiety Direction. The importance of considering all dimensions of perfectionism simultaneously when examining the functional nature of this construct in sport is discussed.

Fluctuating asymmetry, sociosexuality, and intrasexual competitive tactics.

PubMed

Simpson, J A; Gangestad, S W; Christensen, P N; Leck, K

1999-01-01

Heterosexual men and women were told they were competing with another same-sex individual for a date with an attractive opposite-sex interviewer. After answering 6 questions, participants were asked to tell the competitor why the interviewer should choose them over the competitor. Participants' videotaped behavior was coded for different behavioral tactics. Men who were more symmetrical and who had a more unrestricted sociosexual orientation were more likely to use direct competition tactics than were less symmetrical and restricted men. Restricted men accentuated their positive personal qualities, presenting themselves as "nice guys." Structural equation modeling revealed that fluctuating asymmetry (FA) was directly associated with the use of direct competition tactics. However, the link between FA and presenting oneself as a nice guy was mediated through sociosexuality. No effects were found for women.

Sexual Selection on male cuticular hydrocarbons via male-male competition and female choice.

PubMed

Lane, S M; Dickinson, A W; Tregenza, T; House, C M

2016-07-01

Traditional views of sexual selection assumed that male-male competition and female mate choice work in harmony, selecting upon the same traits in the same direction. However, we now know that this is not always the case and that these two mechanisms often impose conflicting selection on male sexual traits. Cuticular hydrocarbons (CHCs) have been shown to be linked to both social dominance and male attractiveness in several insect species. However, although several studies have estimated the strength and form of sexual selection imposed on male CHCs by female mate choice, none have established whether these chemical traits are also subject to sexual selection via male-male competition. Using a multivariate selection analysis, we estimate and compare sexual selection exerted by male-male competition and female mate choice on male CHC composition in the broad-horned flour beetle Gnatocerus cornutus. We show that male-male competition exerts strong linear selection on both overall CHC abundance and body size in males, while female mate choice exerts a mixture of linear and nonlinear selection, targeting not just the overall amount of CHCs expressed but the relative abundance of specific hydrocarbons as well. We discuss the potential implications of this antagonistic selection with regard to male reproductive success. © 2016 The Authors. Journal of Evolutionary Biology published by John Wiley & Sons Ltd on behalf of European Society for Evolutionary Biology.

The role of spatial and temporal heterogeneity and competition in structuring trematode communities in the great pond snail, Lymnaea stagnalis (L.)

USGS Publications Warehouse

Soldánová, Miroslava; Kuris, Armand M.; Scholz, Tomáš; Lafferty, Kevin D.

2012-01-01

We assessed how spatial and temporal heterogeneity and competition structure larval trematode communities in the pulmonate snail Lymnaea stagnalis. To postulate a dominance hierarchy, mark-release-recapture was used to monitor replacements of trematode species within snails over time. In addition, we sampled the trematode community in snails in different ponds in 3 consecutive years. A total of 7,623 snails (10,382 capture events) was sampled in 7 fishponds in the Jindřichův Hradec and Třeboň areas in South Bohemia (Czech Republic) from August 2006 to October 2008. Overall, 39% of snails were infected by a community of 14 trematode species; 7% of snails were infected with more than 1 trematode species (constituting 16 double- and 4 triple-species combinations). Results of the null-model analyses suggested that spatial heterogeneity in recruitment among ponds isolated trematode species from each other, whereas seasonal pulses in recruitment increased species interactions in some ponds. Competitive exclusion among trematodes led to a rarity of multiple infections compared to null-model expectations. Competitive relationships among trematode species were hypothesized as a dominance hierarchy based on direct evidence of replacement and invasion and on indirect evidence. Seven top dominant species with putatively similar competitive abilities (6 rediae and 1 sporocyst species) reduced the prevalence of the other trematode species developing in sporocysts only.

Measuring the Indonesian provinces competitiveness by using PCA technique

NASA Astrophysics Data System (ADS)

Runita, Ditha; Fajriyah, Rohmatul

2017-12-01

Indonesia is a country which has vast teritoty. It has 34 provinces. Building local competitiveness is critical to enhance the long-term national competitiveness especially for a country as diverse as Indonesia. A competitive local government can attract and maintain successful firms and increase living standards for its inhabitants, because investment and skilled workers gravitate from uncompetitive regions to more competitive ones. Altough there are other methods to measuring competitiveness, but here we have demonstrated a simple method using principal component analysis (PCA). It can directly be applied to correlated, multivariate data. The analysis on Indonesian provinces provides 3 clusters based on the competitiveness measurement and the clusters are Bad, Good and Best perform provinces.

The role of growth form and correlated traits in competitive ranking of six perennial ruderal plant species grown in unbalanced mixtures

NASA Astrophysics Data System (ADS)

Dietz, Hansjörg; Steinlein, Thomas; Ullmann, Isolde

1998-02-01

The competitive abilities of six perennial ruderal plants of three different growth forms were compared via yield measures using an additive diallel experimental design with unbalanced mixtures (9:3 or 3:9 plants per pot, respectively). Thus, in a given mixture species A was grown in two configurations: three individuals in centre position of the pot together with nine plants of species B in border position and vice versa. Effect competitive abilities as well as response competitive abilities of the species were significantly related to canopy height and plant biomass. The species with lower rosette growth form and smaller biomasses were weaker competitors than the species possessing elevated canopies along with higher biomasses, whereas total leaf area was not significantly correlated with competitive ability between species. Species differences in competitive ability were stronger between the plants grown in the central position than between those grown in the border position. Furthermore, interactions between species-specific traits and configuration could be observed, indicating the importance of species proportions and arrangement patterns for evaluation of competitive outcome in the field. The degree of complete transitivity of the competitive network of the six ruderal species, which was significantly higher than expected under the null model in our experimental design, also seemed to depend on species proportions in mixture. Shifts in root:shoot ratio of the centre plants when faced with competition by the border plants were in the direction of higher shoot allocation for the weak competitors with rosette growth form irrespective of the neighbour species, except for Bunias orientalis, which showed a more plastic response. The stronger competitors showed higher root allocation ( Urtica dioica) or were hardly affected at all. Consistent with the results of our experiment, the weaker competitors occur at rather frequently disturbed and therefore transient field sites whereas the stronger competitors predominate at infrequently disturbed sites during several phases of succession.

Negative plant-soil feedbacks increase with plant abundance, and are unchanged by competition.

PubMed

Maron, John L; Laney Smith, Alyssa; Ortega, Yvette K; Pearson, Dean E; Callaway, Ragan M

2016-08-01

Plant-soil feedbacks and interspecific competition are ubiquitous interactions that strongly influence the performance of plants. Yet few studies have examined whether the strength of these interactions corresponds with the abundance of plant species in the field, or whether feedbacks and competition interact in ways that either ameliorate or exacerbate their effects in isolation. We sampled soil from two intermountain grassland communities where we also measured the relative abundance of plant species. In greenhouse experiments, we quantified the direction and magnitude of plant-soil feedbacks for 10 target species that spanned a range of abundances in the field. In soil from both sites, plant-soil feedbacks were mostly negative, with more abundant species suffering greater negative feedbacks than rare species. In contrast, the average response to competition for each species was unrelated with its abundance in the field. We also determined how competitive response varied among our target species when plants competed in live vs. sterile soil. Interspecific competition reduced plant size, but the strength of this negative effect was unchanged by plant-soil feedbacks. Finally, when plants competed interspecifically, we asked how conspecific-trained, heterospecific-trained, and sterile soil influenced the competitive responses of our target species and how this varied depending on whether target species were abundant or rare in the field. Here, we found that both abundant and rare species were not as harmed by competition when they grew in heterospecific-trained soil compared to when they grew in conspecific-cultured soil. Abundant species were also not as harmed by competition when growing in sterile vs. conspecific-trained soil, but this was not the case for rare species. Our results suggest that abundant plants accrue species-specific soil pathogens to a greater extent than rare species. Thus, negative feedbacks may be critical for preventing abundant species from becoming even more abundant than rare species. © 2016 by the Ecological Society of America.

A comparison of directed search target detection versus in-scene target detection in Worldview-2 datasets

NASA Astrophysics Data System (ADS)

Grossman, S.

2015-05-01

Since the events of September 11, 2001, the intelligence focus has moved from large order-of-battle targets to small targets of opportunity. Additionally, the business community has discovered the use of remotely sensed data to anticipate demand and derive data on their competition. This requires the finer spectral and spatial fidelity now available to recognize those targets. This work hypothesizes that directed searches using calibrated data perform at least as well as inscene manually intensive target detection searches. It uses calibrated Worldview-2 multispectral images with NEF generated signatures and standard detection algorithms to compare bespoke directed search capabilities against ENVI™ in-scene search capabilities. Multiple execution runs are performed at increasing thresholds to generate detection rates. These rates are plotted and statistically analyzed. While individual head-to-head comparison results vary, 88% of the directed searches performed at least as well as in-scene searches with 50% clearly outperforming in-scene methods. The results strongly support the premise that directed searches perform at least as well as comparable in-scene searches.

Linear feedback stabilization of a dispersively monitored qubit

NASA Astrophysics Data System (ADS)

Patti, Taylor Lee; Chantasri, Areeya; García-Pintos, Luis Pedro; Jordan, Andrew N.; Dressel, Justin

2017-08-01

The state of a continuously monitored qubit evolves stochastically, exhibiting competition between coherent Hamiltonian dynamics and diffusive partial collapse dynamics that follow the measurement record. We couple these distinct types of dynamics together by linearly feeding the collected record for dispersive energy measurements directly back into a coherent Rabi drive amplitude. Such feedback turns the competition cooperative and effectively stabilizes the qubit state near a target state. We derive the conditions for obtaining such dispersive state stabilization and verify the stabilization conditions numerically. We include common experimental nonidealities, such as energy decay, environmental dephasing, detector efficiency, and feedback delay, and show that the feedback delay has the most significant negative effect on the feedback protocol. Setting the measurement collapse time scale to be long compared to the feedback delay yields the best stabilization.

Fine root responses to temporal nutrient heterogeneity and competition in seedlings of two tree species with different rooting strategies.

PubMed

Wang, Peng; Shu, Meng; Mou, Pu; Weiner, Jacob

2018-03-01

There is little direct evidence for effects of soil heterogeneity and root plasticity on the competitive interactions among plants. In this study, we experimentally examined the impacts of temporal nutrient heterogeneity on root growth and interactions between two plant species with very different rooting strategies: Liquidambar styraciflua (sweet gum), which shows high root plasticity in response to soil nutrient heterogeneity, and Pinus taeda (loblolly pine), a species with less plastic roots. Seedlings of the two species were grown in sandboxes in inter- and intraspecific combinations. Nutrients were applied in a patch either in a stable (slow-release) or in a variable (pulse) manner. Plant aboveground biomass, fine root mass, root allocation between nutrient patch and outside the patch, and root vertical distribution were measured. L. styraciflua grew more aboveground (40% and 27% in stable and variable nutrient treatment, respectively) and fine roots (41% and 8% in stable and variable nutrient treatment, respectively) when competing with P. taeda than when competing with a conspecific individual, but the growth of P. taeda was not changed by competition from L. styraciflua . Temporal variation in patch nutrient level had little effect on the species' competitive interactions. The more flexible L. styraciflua changed its vertical distribution of fine roots in response to competition from P. taeda , growing more roots in deeper soil layers compared to its roots in conspecific competition, leading to niche differentiation between the species, while the fine root distribution of P. taeda remained unchanged across all treatments. Synthesis . L. styraciflua showed greater flexibility in root growth by changing its root vertical distribution and occupying space of not occupied by P. taeda . This flexibility gave L. styraciflua an advantage in interspecific competition.

Climate-driven Sympatry does not Lead to Foraging Competition Between Adélie and Gentoo Penguins

NASA Astrophysics Data System (ADS)

Cimino, M. A.; Moline, M. A.; Fraser, W.; Patterson-Fraser, D.; Oliver, M. J.

2016-02-01

Climate-driven sympatry may lead to competition for food resources between species, population shifts and changes in ecosystem structure. Rapid warming in the West Antarctic Peninsula (WAP) is coincident with increasing gentoo penguin and decreasing Adélie penguin populations, suggesting that competition for food may exacerbate the Adélie penguin decline. At Palmer Station, we tested for foraging competition between these species by comparing their prey, Antarctic krill, distributions and penguin foraging behaviors on fine scales. To study these predator-prey dynamics, we simultaneously deployed penguin satellite transmitters, and a REMUS autonomous underwater vehicle that acoustically detected krill aggregations and measured physical and biological properties of the water column. We detected krill aggregations within the horizontal and vertical foraging ranges of Adélie and gentoo penguin. In the upper 100 m of the water column, the distribution of krill aggregations were mainly associated with CHL and light, suggesting that krill selected for habitats that balance the need to consume food and avoid predation. Adélie and gentoo penguins mainly had spatially segregated foraging areas but in areas of overlap, gentoo penguins switched foraging behavior by foraging at deeper depths, a strategy which limits competition with Adélie penguins. This suggests that climate-driven sympatry does not necessarily result in competitive exclusion. Contrary to a recent theory, which suggests that increased competition for krill is the major driver of Adélie penguin population declines, we suggest that declines in Adélie penguins along the WAP are more likely due to direct and indirect climate impacts on their life histories.

Within-host competitive exclusion among species of the anther smut pathogen

PubMed Central

Gold, Alexander; Giraud, Tatiana; Hood, Michael E

2009-01-01

Background Host individuals represent an arena in which pathogens compete for resources and transmission opportunities, with major implications for the evolution of virulence and the structure of populations. Studies to date have focused on competitive interactions within pathogen species, and the level of antagonism tends to increase with the genetic distance between competitors. Anther-smut fungi, in the genus Microbotryum, have emerged as a tractable model for within-host competition. Here, using two pathogen species that are frequently found in sympatry, we investigated whether the antagonism seen among genotypes of the same species cascades up to influence competition among pathogen species. Results Sequential inoculation of hosts showed that a resident infection most often excludes a challenging pathogen genotype, which is consistent with prior studies. However, the challenging pathogen was significantly more likely to invade the already-infected host if the resident infection was a conspecific genotype compared to challenges involving a closely related species. Moreover, when inter-specific co-infection occurred, the pathogens were highly segregated within the host, in contrast to intra-specific co-infection. Conclusion We show evidence that competitive exclusion during infection can be greater among closely related pathogen species than among genotypes within species. This pattern follows from prior studies demonstrating that genetic distance and antagonistic interactions are positively correlated in Microbotryum. Fungal vegetative incompatibility is a likely mechanism of direct competitive interference, and has been shown in some fungi to be effective both within and across species boundaries. For systems where related pathogen species frequently co-occur in the same host populations, these competitive dynamics may substantially impact the spatial segregation of pathogen species. PMID:19422703

Mathematics and Engineering in Real Life through Mathematical Competitions

ERIC Educational Resources Information Center

More, M.

2018-01-01

We bring out an experience of organizing mathematical competitions that can be used as a medium to motivate the student and teacher minds in new directions of thinking. This can contribute to fostering research, innovation and provide a hands-on experience of mathematical concepts with the real world. Mathematical competitions can be used to build…

Competition: the game everyone's playing.

PubMed

Blanton, W B

1980-05-01

The need of all hospitals to make a profit and the key role of census in the creation of that profit have led to a crisis in census marked by strong competition between hospitals, administrators, and physicians. This article examines how hospitals compete for patients and physicians and the need for the direct participation of the hospital board in the competitive struggle.

2010-2011 Inventors Competition--Winners of the "Gimme Shelter" Competition

ERIC Educational Resources Information Center

Tech Directions, 2011

2011-01-01

The number of entries to this year's "Tech Directions" Inventors Competition exceeded even the record set by the 2009-2010 contest--and gave engineer/inventor Harry T. Roman quite a judging challenge. This year's challenge called on students to propose designs for inexpensive, portable shelters that could be used by people made homeless by natural…

Health care competition, strategic mission, and patient satisfaction: research model and propositions

PubMed Central

Rivers, Patrick A.; Glover, Saundra H.

2010-01-01

Purpose In all industries, competition among businesses has long been encouraged as a mechanism to increase value for patients. In other words, competition ensures the provision of better products and services to satisfy the needs of customers This paper aims to develop a model that can be used to empirically investigate a number of complex issues and relationships associated with competition in the health care industry. Design/methodology/approach A literature review was conducted. A total of 50 items of literature related to the subject were reviewed.. Various perspectives of competition, the nature of service quality, health system costs, and patient satisfaction in health care are examined Findings A model of the relationship among these variables is developed. The model depicts patient satisfaction as an outcome measure directly dependent on competition. Quality of care and health care systems costs, while also directly dependent on the strategic mission and goals, are considered as determinants of customer satisfaction as well. The model is discussed in the light of propositions for empirical research. Practical implications Empirical studies based on the model proposed in this paper should help identify areas with significant impact on patient satisfaction while maintaining high quality of service at lower costs in a competitive environment. Originality/value The authors develop a research model which included propositions to examine the complex issues of competition in the health care industry. PMID:19579575

Stress pulls us apart: anxiety leads to differences in competitive confidence under stress.

PubMed

Goette, Lorenz; Bendahan, Samuel; Thoresen, John; Hollis, Fiona; Sandi, Carmen

2015-04-01

Social competition is a fundamental mechanism of evolution and plays a central role in structuring individual interactions and communities. Little is known about the factors that affect individuals' competitive success, particularly in humans. Key factors might include stress, a major evolutionary pressure that can affect the establishment of social hierarchies in animals, and individuals' trait anxiety, which largely determines susceptibility to stress and constitutes an important determinant of differences in competitive outcomes. Using an economic-choice experiment to assess competitive self-confidence in 229 human subjects we found that, whereas competitive self-confidence is unaffected by an individual's anxiety level in control conditions, exposure to the Trier social stress test for groups drives the behavior of individuals apart: low-anxiety individuals become overconfident, and high-anxiety individuals become underconfident. Cortisol responses to stress were found to relate to self-confidence, with the direction of the effects depending on trait anxiety. Our findings identify stress as a major regulator of individuals' competitiveness, affecting self-confidence in opposite directions in high and low anxious individuals. Therefore, our findings imply that stress may provide a new channel for generating social and economic inequality and, thus, not only be a consequence, but also a cause of inequality through its impact on competitive self-confidence and decision making in financially-relevant situations. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Effects of confidence and anxiety on flow state in competition.

PubMed

Koehn, Stefan

2013-01-01

Confidence and anxiety are important variables that underlie the experience of flow in sport. Specifically, research has indicated that confidence displays a positive relationship and anxiety a negative relationship with flow. The aim of this study was to assess potential direct and indirect effects of confidence and anxiety dimensions on flow state in tennis competition. A sample of 59 junior tennis players completed measures of Competitive State Anxiety Inventory-2d and Flow State Scale-2. Following predictive analysis, results showed significant positive correlations between confidence (intensity and direction) and anxiety symptoms (only directional perceptions) with flow state. Standard multiple regression analysis indicated confidence as the only significant predictor of flow. The results confirmed a protective function of confidence against debilitating anxiety interpretations, but there were no significant interaction effects between confidence and anxiety on flow state.

Strategies to enhance price and quality competition in health care: lessons learned from tracking local markets.

PubMed

Lesser, Cara S; Ginsburg, Paul B

2006-06-01

Drawing on observations from tracking changes in local health care markets over the past ten years, this article critiques two Federal Trade Commission and Department of Justice recommendations to enhance price and quality competition. First, we take issue with the notion that consumers, acting independently, will drive greater competition in health care markets. Rather we suggest an important role remains for trusted agents who can analyze inherently complex price and quality information and negotiate on consumers' behalf. With aggregated information identifying providers who deliver cost-effective care, consumers would be better positioned to respond to financial incentives about where to seek care and thereby drive more meaningful competition among providers to reduce costs and improve quality. Second, we take issue with the FTC/DOJ recommendation to provide more direct subsidies to prevent distortions in competition. In the current political environment, it is not practical to provide direct subsidies for all of the unfunded care that exists in health care markets today; instead, some interference with competition may be necessary to protect cross subsidies. Barriers can be reduced, though, by revising pricing policies that have resulted in marked disparities in the relative profitability of different services.

Sperm competition, immunity, selfish genes and cancer.

PubMed

Lewis, Z; Price, T A R; Wedell, N

2008-10-01

Sperm competition is widespread and has played an important role in shaping male reproductive characters such as testis size and numbers of sperm produced, and this is reflected in the rapid evolution of many reproductive genes. Additionally, sperm competition has been implicated in the rapid evolution of seminal fluids. However, our understanding of the molecular basis of many traits thought to be important in sperm competition is rudimentary. Furthermore, links between sperm competition and a range of issues not directly related to reproduction are only just beginning to be explored. These include associations between sperm competition and selfish genes, immunity and diseases such as cancer.We briefly review these topics and suggest areas we consider worthy of additional research.

The training intensity distribution among well-trained and elite endurance athletes

PubMed Central

Stöggl, Thomas L.; Sperlich, Billy

2015-01-01

Researchers have retrospectively analyzed the training intensity distribution (TID) of nationally and internationally competitive athletes in different endurance disciplines to determine the optimal volume and intensity for maximal adaptation. The majority of studies present a “pyramidal” TID with a high proportion of high volume, low intensity training (HVLIT). Some world-class athletes appear to adopt a so-called “polarized” TID (i.e., significant % of HVLIT and high-intensity training) during certain phases of the season. However, emerging prospective randomized controlled studies have demonstrated superior responses of variables related to endurance when applying a polarized TID in well-trained and recreational individuals when compared with a TID that emphasizes HVLIT or threshold training. The aims of the present review are to: (1) summarize the main responses of retrospective and prospective studies exploring TID; (2) provide a systematic overview on TIDs during preparation, pre-competition, and competition phases in different endurance disciplines and performance levels; (3) address whether one TID has demonstrated greater efficacy than another; and (4) highlight research gaps in an effort to direct future scientific studies. PMID:26578968

Insider versus outsider executive succession: The relationship to hospital efficiency.

PubMed

Ford, Eric W; Lowe, Kevin B; Silvera, Geoffrey B; Babik, Dmytro; Huerta, Timothy R

The relationship between Chief Executive Officer (CEO) succession and hospitals' competitive performance is an area of interest for health services researchers. Of particular interest is the impact on overall strategic direction and health system performance that results from selecting a CEO from inside the firm as opposed to seeking outside leadership. Empirical work-to-date has yielded mixed results. Much of this variability has been attributed to design flaws; however, in the absence of a clear message from the evidence, the preference for hiring "outsiders" continues to grow. This paper investigates on the extent to which insider CEO succession versus outsider succession impacts hospitals' competitive advantage vis-à-vis a sample of organizations that compete in the same sector. A hospital matching protocol based on propensity scores is used to control for endogeneity and makes comparisons of productivity across organizations through the use of stochastic frontier estimation. Succession negatively impacts hospitals' productivity, and firms with outsider CEO succession events closed the gap toward the competitive advantage frontier faster than comparable firms with insider successions. More research needs to be done on succession planning and its impact on CEO turnover.

The training intensity distribution among well-trained and elite endurance athletes.

PubMed

Stöggl, Thomas L; Sperlich, Billy

2015-01-01

Researchers have retrospectively analyzed the training intensity distribution (TID) of nationally and internationally competitive athletes in different endurance disciplines to determine the optimal volume and intensity for maximal adaptation. The majority of studies present a "pyramidal" TID with a high proportion of high volume, low intensity training (HVLIT). Some world-class athletes appear to adopt a so-called "polarized" TID (i.e., significant % of HVLIT and high-intensity training) during certain phases of the season. However, emerging prospective randomized controlled studies have demonstrated superior responses of variables related to endurance when applying a polarized TID in well-trained and recreational individuals when compared with a TID that emphasizes HVLIT or threshold training. The aims of the present review are to: (1) summarize the main responses of retrospective and prospective studies exploring TID; (2) provide a systematic overview on TIDs during preparation, pre-competition, and competition phases in different endurance disciplines and performance levels; (3) address whether one TID has demonstrated greater efficacy than another; and (4) highlight research gaps in an effort to direct future scientific studies.

Green Flight Challenge

NASA Image and Video Library

2011-09-28

CAFE Foundation Hanger Boss Mike Fenn directs the e-Genius aircraft to the start of the speed competition during the 2011 Green Flight Challenge, sponsored by Google, at the Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. on Thursday, Sept. 29, 2011. NASA and the Comparative Aircraft Flight Efficiency (CAFE) Foundation are having the challenge with the goal to advance technologies in fuel efficiency and reduced emissions with cleaner renewable fuels and electric aircraft. Photo Credit: (NASA/Bill Ingalls)

Green Flight Challenge

NASA Image and Video Library

2011-09-28

CAFE Foundation Hanger Boss Mike Fenn directs the EcoEagle aircraft to the start of the speed competition during the 2011 Green Flight Challenge, sponsored by Google, at the Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. on Thursday, Sept. 29, 2011. NASA and the Comparative Aircraft Flight Efficiency (CAFE) Foundation are having the challenge with the goal to advance technologies in fuel efficiency and reduced emissions with cleaner renewable fuels and electric aircraft. Photo Credit: (NASA/Bill Ingalls)

Dispersal Timing: Emigration of Insects Living in Patchy Environments.

PubMed

Lakovic, Milica; Poethke, Hans-Joachim; Hovestadt, Thomas

2015-01-01

Dispersal is a life-history trait affecting dynamics and persistence of populations; it evolves under various known selective pressures. Theoretical studies on dispersal typically assume 'natal dispersal', where individuals emigrate right after birth. But emigration may also occur during a later moment within a reproductive season ('breeding dispersal'). For example, some female butterflies first deposit eggs in their natal patch before migrating to other site(s) to continue egg-laying there. How breeding compared to natal dispersal influences the evolution of dispersal has not been explored. To close this gap we used an individual-based simulation approach to analyze (i) the evolution of timing of breeding dispersal in annual organisms, (ii) its influence on dispersal (compared to natal dispersal). Furthermore, we tested (iii) its performance in direct evolutionary contest with individuals following a natal dispersal strategy. Our results show that evolution should typically result in lower dispersal under breeding dispersal, especially when costs of dispersal are low and population size is small. By distributing offspring evenly across two patches, breeding dispersal allows reducing direct sibling competition in the next generation whereas natal dispersal can only reduce trans-generational kin competition by producing highly dispersive offspring in each generation. The added benefit of breeding dispersal is most prominent in patches with small population sizes. Finally, the evolutionary contests show that a breeding dispersal strategy would universally out-compete natal dispersal.

Their pain gives us pleasure: How intergroup dynamics shape empathic failures and counter-empathic responses

PubMed Central

Cikara, M.; Bruneau, E.; Van Bavel, J. J.; Saxe, R.

2014-01-01

Despite its early origins and adaptive functions, empathy is not inevitable; people routinely fail to empathize with others, especially members of different social or cultural groups. In five experiments, we systematically explore how social identity, functional relations between groups, competitive threat, and perceived entitativity contribute to intergroup empathy bias: the tendency not only to empathize less with out-group relative to in-group members, but also feel pleasure in response to their pain (and pain in response to their pleasure). When teams are set in direct competition, affective responses to competition-irrelevant events are characterized not only by less empathy toward out-group relative to in-group members, but also by increased counter-empathic responses: Schadenfreude and Glückschmerz (Experiment 1). Comparing responses to in-group and out-group targets against responses to unaffiliated targets in this competitive context suggests that intergroup empathy bias may be better characterized by out-group antipathy rather than extraordinary in-group empathy (Experiment 2). We find also that intergroup empathy bias is robust to changes in relative group standing—feedback indicating that the out-group has fallen behind (Experiment 3a) or is no longer a competitive threat (Experiment 3b) does not reduce the bias. However, reducing perceived in-group and out-group entitativity can significantly attenuate intergroup empathy bias (Experiment 4). This research establishes the boundary conditions of intergroup empathy bias and provides initial support for a more integrative framework of group-based empathy. PMID:25082998

[Challenge and opportunity of entry to WTO brings to scientific and technological periodical].

PubMed

Tian, Yun-Mei

2004-11-01

After our country enters WTO, confronted with the direct influence in big international market opening, editorial department will face fierce competition. Selecting the superior and eliminate the inferior will test every publishing house and every magazine directly. In order to improve the competition level, author has analyzed the current situation of China's periodical development, and then explored the scientific and technological periodical opportunity and challenge faced under the new situation.

Major Hurdles for the Evolution of Sociality.

PubMed

Korb, Judith; Heinze, Jürgen

2016-01-01

Why do most animals live solitarily, while complex social life is restricted to a few cooperatively breeding vertebrates and social insects? Here, we synthesize concepts and theories in social evolution and discuss its underlying ecological causes. Social evolution can be partitioned into (a) formation of stable social groups, (b) evolution of helping, and (c) transition to a new evolutionary level. Stable social groups rarely evolve due to competition over food and/or reproduction. Food competition is overcome in social insects with central-place foraging or bonanza-type food resources, whereas competition over reproduction commonly occurs because staying individuals are rarely sterile. Hence, the evolution of helping is shaped by direct and indirect fitness options and helping is only altruism if it reduces the helper's direct fitness. The helper's capability to gain direct fitness also creates within-colony conflict. This prevents transition to a new evolutionary level.

The analysis of export commodity competitiveness in Central Java Province at period 2011-2015

NASA Astrophysics Data System (ADS)

Elysi, M. G.; Darsono; Riptanti, E. W.

2018-03-01

This study aims to determine the competitiveness of furniture export in Central Java Province Indonesia in terms of comparative and competitive advantages and to formulate the strategies to enhance the competitiveness of furniture export in Central Java Province. Descriptive analytic method was used for this research. Data used in this research are primary and secondary data. Data were analyzed using RCA (Revealed Comparative Advantage), TSI (Trade Specialization Index) and SOAR (Strength, Opportunity, Aspiration, Result). The results showed that furniture commodity in Central Java Province had strong comparative competitiveness with the value of RCA>1 and had strong competitiveness with positive index values in the range of 0 to 1. Based on SOAR analysis, strategy measures can be formulated, namely maintaining the existing and expanding targeted markets, improving product designs (innovations) and improving raw materials efficiency.

Asymmetric predictability and cognitive competition in football penalty shootouts.

PubMed

Misirlisoy, Erman; Haggard, Patrick

2014-08-18

Sports provide powerful demonstrations of cognitive strategies underlying competitive behavior. Penalty shootouts in football (soccer) involve direct competition between elite players and absorb the attention of millions. The penalty shootout between Germany and England in the 1990 World Cup semifinal was viewed by an estimated 46.49% of the UK population. In a penalty shootout, a goalkeeper must defend their goal without teammate assistance while an opposing series of kickers aim to kick the ball past them into the net. As in many sports, the ball during a penalty kick often approaches too quickly for the goalkeeper to react to its direction of motion; instead, the goalkeeper must guess the likely direction of the kick, and dive in anticipation, if they are to have a chance of saving the shot. We examined all 361 kicks from the 37 penalty shootouts that occurred in World Cup and Euro Cup matches over a 36-year period from 1976 to 2012 and show that goalkeepers displayed a clear sequential bias. Following repeated kicks in the same direction, goalkeepers became increasingly likely to dive in the opposite direction on the next kick. Surprisingly, kickers failed to exploit these goalkeeper biases. Our findings highlight the importance of monitoring and predicting sequential behavior in real-world competition. Penalty shootouts pit one goalkeeper against several kickers in rapid succession. Asymmetries in the cognitive capacities of an individual versus a group could produce significant advantages over opponents. Copyright © 2014 Elsevier Ltd. All rights reserved.

Gender differences in testosterone and cortisol response to competition.

PubMed

Kivlighan, Katie T; Granger, Douglas A; Booth, Alan

2005-01-01

This study examined intra-individual change in testosterone, cortisol, and hormone-behavior relationships in response to a rowing ergometer competition. Forty-six members (23 females) of a university crew team provided saliva samples before, 20- and 40-min post-competition, as well as baselines on a non-competition day. Behavioral assessments included measures of previous rowing experience, dominance, competitiveness, bonding with teammates, pre- and post-competition mental state and performance. Men's and women's endocrine responses to this competitive setting were more different than alike and varied by level of competitive experience, the specific phase of the competitive event, and the particular hormone measured. Inter-individual differences in testosterone and cortisol were differentially associated with social affiliation with teammates but rarely with dominance or competitiveness. Theoretically, the findings support the integration of features of the 'tend and befriend' model with the biosocial model of status, and suggest future research directions that may lead to clarification and refinement of those ideas.

Relative importance of competition and plant-soil feedback, their synergy, context dependency and implications for coexistence.

PubMed

Lekberg, Ylva; Bever, James D; Bunn, Rebecca A; Callaway, Ragan M; Hart, Miranda M; Kivlin, Stephanie N; Klironomos, John; Larkin, Beau G; Maron, John L; Reinhart, Kurt O; Remke, Michael; van der Putten, Wim H

2018-06-12

Plants interact simultaneously with each other and with soil biota, yet the relative importance of competition vs. plant-soil feedback (PSF) on plant performance is poorly understood. Using a meta-analysis of 38 published studies and 150 plant species, we show that effects of interspecific competition (either growing plants with a competitor or singly, or comparing inter- vs. intraspecific competition) and PSF (comparing home vs. away soil, live vs. sterile soil, or control vs. fungicide-treated soil) depended on treatments but were predominantly negative, broadly comparable in magnitude, and additive or synergistic. Stronger competitors experienced more negative PSF than weaker competitors when controlling for density (inter- to intraspecific competition), suggesting that PSF could prevent competitive dominance and promote coexistence. When competition was measured against plants growing singly, the strength of competition overwhelmed PSF, indicating that the relative importance of PSF may depend not only on neighbour identity but also density. We evaluate how competition and PSFs might interact across resource gradients; PSF will likely strengthen competitive interactions in high resource environments and enhance facilitative interactions in low-resource environments. Finally, we provide a framework for filling key knowledge gaps and advancing our understanding of how these biotic interactions influence community structure. © 2018 John Wiley & Sons Ltd/CNRS.

Indirect competitive assays on DVD for direct multiplex detection of drugs of abuse in oral fluids.

PubMed

Zhang, Lingling; Li, Xiaochun; Li, Yunchao; Shi, Xiaoli; Yu, Hua-Zhong

2015-02-03

On-site oral fluid testing for drugs of abuse has become prominent in order to take immediate administrative action in an enforcement process. Herein, we report a DVD technology-based indirect competitive immunoassay platform for the quantitative detection of drugs of abuse. A microfluidic approach was adapted to prepare multiplex immunoassays on a standard DVD-R, an unmodified multimode DVD/Blu-Ray drive to read signal, and a free disc-quality analysis software program to process the data. The DVD assay platform was successfully demonstrated for the simultaneous, quantitative detection of drug candidates (morphine and cocaine) in oral fluids with high selectivity. The detection limit achieved was as low as 1.0 ppb for morphine and 5.0 ppb for cocaine, comparable with that of standard mass spectrometry and ELISA methods.

Interactions of Top-Down and Bottom-Up Mechanisms in Human Visual Cortex

PubMed Central

McMains, Stephanie; Kastner, Sabine

2011-01-01

Multiple stimuli present in the visual field at the same time compete for neural representation by mutually suppressing their evoked activity throughout visual cortex, providing a neural correlate for the limited processing capacity of the visual system. Competitive interactions among stimuli can be counteracted by top-down, goal-directed mechanisms such as attention, and by bottom-up, stimulus-driven mechanisms. Because these two processes cooperate in everyday life to bias processing toward behaviorally relevant or particularly salient stimuli, it has proven difficult to study interactions between top-down and bottom-up mechanisms. Here, we used an experimental paradigm in which we first isolated the effects of a bottom-up influence on neural competition by parametrically varying the degree of perceptual grouping in displays that were not attended. Second, we probed the effects of directed attention on the competitive interactions induced with the parametric design. We found that the amount of attentional modulation varied linearly with the degree of competition left unresolved by bottom-up processes, such that attentional modulation was greatest when neural competition was little influenced by bottom-up mechanisms and smallest when competition was strongly influenced by bottom-up mechanisms. These findings suggest that the strength of attentional modulation in the visual system is constrained by the degree to which competitive interactions have been resolved by bottom-up processes related to the segmentation of scenes into candidate objects. PMID:21228167

Somatotype of elite Italian gymnasts.

PubMed

Massidda, Myosotis; Toselli, Stefania; Brasili, Patricia; Calò, Carla M

2013-09-01

The somatotyping method is especially helpful in sports in which the body could directly influence the biomechanics of movements and the performance's results. The purpose of this study was to determine the somatotype of elite Italian gymnasts and to compare it in terms of competition levels. The sample comprised 64 elite gymnasts (42 females (F), somatotype 1.4-4.4-3.2; and 22 males (M), somatotype 1.6-6.3-2.1) belonging to the Italian National Artistic Gymnastic Team (2007) at different competition levels: Allieve, Junior, and Senior. Mean whole somatotypes, by competition levels, were not significantly different in both sexes (Female gymnasts: Allieve, 1.3-4.6-3.3; Junior, 1.3-4.2-3.6; Senior, 1.7-4.2-2.7; Male gymnasts: Junior, 1.5-6.3-2.5; Senior, 1.7-6.3-1.6). Male Junior gymnasts exhibited greater ectomorphy than Senior athletes (F1,20 = 7.75, p < 0.01). Compared to other elite athletes male and female gymnasts tend to be less endomorphic and more mesomorphic. This study highlighted the peculiarities of the somatotype of Italian elite gymnasts and their strong homogeneity, evident also from the low values of somatotype attitudinal mean (SAM). The results emphasize the need for a specific somatotype to reach an elite level in sport and the need to integrate the somatotype analysis between the scientific instruments for selecting talent also in artistic gymnastics.

Biotic interactions reduce microbial carbon use efficiency

NASA Astrophysics Data System (ADS)

Bradford, M.; Maynard, D. S.

2017-12-01

The efficiency by which microbes decompose organic matter governs the amount of carbon that is retained in microbial biomass versus lost to the atmosphere as respiration. This carbon use efficiency (CUE) is affected by various abiotic conditions, such as temperature and nutrient availability. In biogeochemical model simulations, CUE is a key variable regulating how much soil carbon is stored or lost from ecosystems under simulated global changes, such as climate warming. Theoretically, the physiological costs of biotic interactions such as competition should likewise alter CUE, yet the direction and magnitude of these costs are untested. Here we conduct a microcosm experiment to quantify how competitive interactions among saprotrophic fungi alter growth, respiration, and CUE. Free-living decomposer fungi representing a broad range of traits and phylogenies were grown alone, in pairwise competition, and in multi-species (up to 15) communities. By combing culturing and stable carbon isotope approaches, we could resolve the amount of carbon substrate allocated to fungal biomass versus respiration, and so estimate CUE. By then comparing individual performance to community-level outcomes, we show that species interactions induce consistent declines in CUE, regardless of abiotic conditions. Pairwise competition lowers CUE by as much as 25%, with the magnitude of these costs equal to or greater than the observed variation across abiotic conditions. However, depending on the competitive network structure, increasing species richness led to consistent gains or declines in CUE. Our results suggest that the extent to which microbial-mediated carbon fluxes respond to environmental change may be influenced strongly by competitive interactions. As such, knowledge of abiotic conditions and community composition is necessary to confidently project CUE and hence ecosystem carbon dynamics.

The effects of competition and implicit power motive on men's testosterone, emotion recognition, and aggression.

PubMed

Vongas, John G; Al Hajj, Raghid

2017-06-01

A contribution to a special issue on Hormones and Human Competition. We investigated the effects of competition on men's testosterone levels and assessed whether androgen reactivity was associated with subsequent emotion recognition and reactive and proactive aggression. We also explored whether personalized power (p Power) moderated these relationships. In Study 1, 84 males competed on a number tracing task and interpreted emotions from facial expressions. In Study 2, 72 males competed on the same task and were assessed on proactive and reactive aggression. In both studies, contrary to the biosocial model of status (Mazur, 1985), winners' testosterone levels decreased significantly while losers' levels increased, albeit not significantly. Personalized power moderated the effect of competition outcome on testosterone change in both studies. Using the aggregate sample, we found that the effect of decreased testosterone levels among winners (compared to losers) was significant for individuals low in p Power but not for those with medium or high p Power. Testosterone change was positively related to emotion recognition, but unrelated to either aggression subtype. The testosterone-mediated relationship between winning and losing and emotion recognition was moderated by p Power. In addition, p Power moderated the direct (i.e., non-testosterone mediated) path between competition outcome and emotion recognition and both types of aggression: high p-Power winners were more accurate at deciphering others' emotions than high p-Power losers. Finally, among high p-Power men, winners aggressed more proactively than losers, whereas losers aggressed more reactively than winners. Collectively, these studies highlight the importance of implicit power motivation in modulating hormonal, cognitive, and behavioral outcomes arising from human competition. Copyright © 2017 Elsevier Inc. All rights reserved.

Interspecific interactions between Phragmites australis and Spartina alterniflora along a tidal gradient in the Dongtan wetland, Eastern China.

PubMed

Yuan, Yue; Wang, Kaiyun; Li, Dezhi; Pan, Yu; Lv, Yuanyuan; Zhao, Meixia; Gao, JinJin

2013-01-01

The invasive species Spartina alterniora Loisel was introduced to the eastern coast of China in the 1970s and 1980s for the purposes of land reclamation and the prevention of soil erosion. The resulting interspecific competition had an important influence on the distribution of native vegetation, which makes studying the patterns and mechanisms of the interactions between Spartina alterniora Loisel and the native species Phragmites australis (Cav.) Trin ex Steud in this region very important. There have been some researches on the interspecific interactions between P. australis and S. alterniora in the Dongtan wetland of Chongming, east China, most of which has focused on the comparison of their physiological characteristics. In this paper, we conducted a neighbor removal experiment along a tidal gradient to evaluate the relative competitive abilities of the two species by calculating their relative neighbor effect (RNE) index. We also looked at the influence of environmental stress and disturbance on the competitive abilities of the two species by comparing interaction strength (I) among different tidal zones both for P. australis and S. alterniora. Finally, we measured physiological characteristics of the two species to assess the physiological mechanisms behind their different competitive abilities. Both negative and positive interactions were found between P. australis and S. alterniora along the environmental gradient. When the direction of the competitive intensity index for P. australis and S. alterniora was consistent, the competitive or facilitative effect of S. alterniora on P. australis was stronger than that of P. australis on S. alterniora. The interspecific interactions of P. australis and S. alterniora varied with environmental conditions, as well as with the method used, to measure interspecific interactions.

Response of rice genotypes to weed competition in dry direct-seeded rice in India.

PubMed

Mahajan, Gulshan; Ramesha, Mugalodi S; Chauhan, Bhagirath S

2014-01-01

The differential weed-competitive abilities of eight rice genotypes and the traits that may confer such attributes were investigated under partial weedy and weed-free conditions in naturally occurring weed flora in dry direct-seeded rice during the rainy seasons of 2011 and 2012 at Ludhiana, Punjab, India. The results showed genotypic differences in competitiveness against weeds. In weed-free plots, grain yield varied from 6.6 to 8.9 t ha(-1) across different genotypes; it was lowest for PR-115 and highest for the hybrid H-97158. In partial weedy plots, grain yield and weed biomass at flowering varied from 3.6 to 6.7 t ha(-1) and from 174 to 419 g m(-2), respectively. In partial weedy plots, grain yield was lowest for PR-115 and highest for PR-120. Average yield loss due to weed competition ranged from 21 to 46% in different rice genotypes. The study showed that early canopy closure, high leaf area index at early stage, and high root biomass and volume correlated positively with competitiveness. This study suggests that some traits (root biomass, leaf area index, and shoot biomass at the early stage) could play an important role in conferring weed competitiveness and these traits can be explored for dry-seeded rice.

Response of Rice Genotypes to Weed Competition in Dry Direct-Seeded Rice in India

PubMed Central

Mahajan, Gulshan; Ramesha, Mugalodi S.; Chauhan, Bhagirath S.

2014-01-01

The differential weed-competitive abilities of eight rice genotypes and the traits that may confer such attributes were investigated under partial weedy and weed-free conditions in naturally occurring weed flora in dry direct-seeded rice during the rainy seasons of 2011 and 2012 at Ludhiana, Punjab, India. The results showed genotypic differences in competitiveness against weeds. In weed-free plots, grain yield varied from 6.6 to 8.9 t ha−1 across different genotypes; it was lowest for PR-115 and highest for the hybrid H-97158. In partial weedy plots, grain yield and weed biomass at flowering varied from 3.6 to 6.7 t ha−1 and from 174 to 419 g m−2, respectively. In partial weedy plots, grain yield was lowest for PR-115 and highest for PR-120. Average yield loss due to weed competition ranged from 21 to 46% in different rice genotypes. The study showed that early canopy closure, high leaf area index at early stage, and high root biomass and volume correlated positively with competitiveness. This study suggests that some traits (root biomass, leaf area index, and shoot biomass at the early stage) could play an important role in conferring weed competitiveness and these traits can be explored for dry-seeded rice. PMID:25093205

"Wanna Race?": Primary Student Preference for Competitive or Non-Competitive Singing Games

ERIC Educational Resources Information Center

Roberts, J. Christopher

2016-01-01

This study compared primary student preference for competitive and non-competitive singing games. Students in three intact classes of second graders (n = 65) and three classes of fourth graders (n = 67) at one school in the USA served as subjects. After playing a pair of games, one competitive and one non-competitive, over the course of five…

Consumer-oriented health care reform strategies: a review of the evidence on managed competition and consumer-directed health insurance.

PubMed

Buchmueller, Thomas C

2009-12-01

For many years, leading health care reform proposals have been based on market-oriented strategies. In the 1990s, a number of reform proposals were built around the concept of "managed competition," but more recently, "consumer-directed health care" models have received attention. Although price-conscious consumer demand plays a critical role in both the managed competition and consumer-directed health care models, the two strategies are based on different visions of the health care marketplace and the best way to use market forces to achieve greater systemwide efficiencies. This article reviews the research literature that tests the main hypotheses concerning the two policy strategies. Numerous studies provide consistent evidence that consumers' health plan choices are sensitive to out-of-pocket premiums. The elasticity of demand appears to vary with consumers' health risk, with younger, healthier individuals being more price sensitive. This heterogeneity increases the potential for adverse selection. Biased risk selection also is a concern when the menu of health plan options includes consumer-directed health plans. Several studies confirm that such plans tend to attract healthier enrollees. A smaller number of studies test the main hypothesis regarding consumer-directed health plans, which is that they result in lower medical spending than do more generous plans. These studies find little support for this claim. The experiences of employers that have adopted key elements of managed competition are generally consistent with the key hypotheses underlying that strategy. Research in this area, however, has focused on only a narrow range of questions. Because consumer-directed health care is such a recent phenomenon, research on this strategy is even more limited. Additional studies on both topics would be valuable.

Consumer-Oriented Health Care Reform Strategies: A Review of the Evidence on Managed Competition and Consumer-Directed Health Insurance

PubMed Central

Buchmueller, Thomas C

2009-01-01

Context: For many years, leading health care reform proposals have been based on market-oriented strategies. In the 1990s, a number of reform proposals were built around the concept of “managed competition,” but more recently, “consumer-directed health care” models have received attention. Although price-conscious consumer demand plays a critical role in both the managed competition and consumer-directed health care models, the two strategies are based on different visions of the health care marketplace and the best way to use market forces to achieve greater systemwide efficiencies. Methods: This article reviews the research literature that tests the main hypotheses concerning the two policy strategies. Findings: Numerous studies provide consistent evidence that consumers’ health plan choices are sensitive to out-of-pocket premiums. The elasticity of demand appears to vary with consumers’ health risk, with younger, healthier individuals being more price sensitive. This heterogeneity increases the potential for adverse selection. Biased risk selection also is a concern when the menu of health plan options includes consumer-directed health plans. Several studies confirm that such plans tend to attract healthier enrollees. A smaller number of studies test the main hypothesis regarding consumer-directed health plans, which is that they result in lower medical spending than do more generous plans. These studies find little support for this claim. Conclusions: The experiences of employers that have adopted key elements of managed competition are generally consistent with the key hypotheses underlying that strategy. Research in this area, however, has focused on only a narrow range of questions. Because consumer-directed health care is such a recent phenomenon, research on this strategy is even more limited. Additional studies on both topics would be valuable. PMID:20021587

Analysis of China department water consumption efficiency

NASA Astrophysics Data System (ADS)

Li, Wei; Wang, Xi-Feng; Liu, Jia-Hong

2018-03-01

The water comparable non-competitive input-out model of China in 2002, 2007 and 2012 is established to calculate the department water consumption efficiency. The water direct and complete consumption coefficients of 38 departments are analysed. Agriculture and Electricity and steam supply have the highest water consumption coefficients and utilize water resource mainly by the direct way. Manufacture of food products and tobacco products, Manufacture of textiles, Manufacture of wearing apparel and leather products and Information service activities have high water complete consumption coefficients and affect water consumption mainly by the indirect way. Water complete consumption efficiency measures the efficiency from the view of final product, which reflected the department water use driving force more precisely.

Y-Balance Test Performance Following a Competitive Field Hockey Season: A Pretest-Posttest Study.

PubMed

Hoch, Matthew C; Welsch, Lauren A; Hartley, Emily M; Powden, Cameron J; Hoch, Johanna M

2017-05-22

The Y-Balance Test (YBT) is a dynamic balance assessment used as a preseason musculoskeletal screen to determine injury risk. While the YBT has demonstrated excellent test-retest reliability, it is unknown if YBT performance changes following participation in a competitive athletic season. Determine if a competitive athletic season affects YBT performance in field hockey players. Pretest-posttest. Laboratory. Twenty NCAA Division I women's field hockey players (age=19.55±1.30 years; height=165.10±5.277cm; mass=62.62±4.64kg) from a single team volunteered. Participants had to be free from injury throughout the entire study and participate in all athletic activities. Participants completed data collection sessions prior to (preseason) and following the athletic season (postseason). Between data collections, participants competed in the fall competitive field hockey season, which was ~3 months in duration. During data collection, participants completed the YBT bilaterally. The independent variable was time (preseason, postseason) and the dependent variables were normalized reach distances (anterior, posteromedial, posterolateral, composite) and between-limb symmetry for each reach direction. Differences between preseason and postseason were examined using paired t-tests (p≤0.05) as well as Bland-Altman limits of agreement. Four players sustained a lower extremity injury during the season and were excluded from analysis. There were no significant differences between preseason and postseason reach distances for any reach directions on either limb (p≥0.31) or in the between-limb symmetries (p≥0.52). The limits of agreement analyses determined there was a low mean bias across measurements (≤1.67%); however, the 95% confidence intervals indicated there was high variability within the posterior reach directions over time (±4.75-±14.83%). No changes in YBT performance were identified following a competitive field hockey season in Division I female athletes. However, the variability within the posterior reach directions over time may contribute to the limited use of these directions for injury risk stratification.

A highly rapid and simple competitive enzyme-linked immunosorbent assay for monitoring paralytic shellfish poisoning toxins in shellfish.

PubMed

Kawatsu, Kentaro; Kanki, Masashi; Harada, Tetsuya; Kumeda, Yuko

2014-11-01

Using a streptavidin-coated well plate, a biotin-labelled anti-gonyautoxin 2/3 monoclonal antibody GT-13A, and a decarbamoyl saxitoxin-peroxidase conjugate, a direct competitive enzyme-linked immunosorbent assay (PSP-ELISA) was developed for monitoring paralytic shellfish poisoning (PSP) toxins in shellfish. This assay is simple to perform and can be completed in approximately 20 min. The PSP-ELISA was compared to the mouse bioassay (MBA) for the detection of PSP toxins in shellfish samples (n=83) collected from the coast of Osaka Prefecture, Japan. When positive and negative results were indicated based on the regulatory limit for PSP toxins (4 mouse unit(MU)/g of shellfish meat), the PSP-ELISA results showed a sensitivity of 100% (25 of 25) and a specificity of 89.7% (52 of 58 samples) compared to the MBA results. These results suggest that the PSP-ELISA could be used as a rapid and simple screening method prior to the MBA. Copyright © 2014 Elsevier Ltd. All rights reserved.

78 FR 38981 - Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-28

... ``LIMITED COMPETITION: ENHANCING INVESTMENTS COMPARATIVE EFFECTIVENESS RESEARCH RESOURCES GRANTS (R01... COMPETITION: ENHANCING INVESTMENTS COMPARATIVE EFFECTIVENESS RESEARCH RESOURCES GRANTS (R01)'' are to be...

Review of the BCI Competition IV

PubMed Central

Tangermann, Michael; Müller, Klaus-Robert; Aertsen, Ad; Birbaumer, Niels; Braun, Christoph; Brunner, Clemens; Leeb, Robert; Mehring, Carsten; Miller, Kai J.; Müller-Putz, Gernot R.; Nolte, Guido; Pfurtscheller, Gert; Preissl, Hubert; Schalk, Gerwin; Schlögl, Alois; Vidaurre, Carmen; Waldert, Stephan; Blankertz, Benjamin

2012-01-01

The BCI competition IV stands in the tradition of prior BCI competitions that aim to provide high quality neuroscientific data for open access to the scientific community. As experienced already in prior competitions not only scientists from the narrow field of BCI compete, but scholars with a broad variety of backgrounds and nationalities. They include high specialists as well as students. The goals of all BCI competitions have always been to challenge with respect to novel paradigms and complex data. We report on the following challenges: (1) asynchronous data, (2) synthetic, (3) multi-class continuous data, (4) session-to-session transfer, (5) directionally modulated MEG, (6) finger movements recorded by ECoG. As after past competitions, our hope is that winning entries may enhance the analysis methods of future BCIs. PMID:22811657

Direct competitive chemiluminescence immunoassays based on gold-coated magnetic particles for detection of chloramphenicol.

PubMed

Liang, Xiaohui; Fang, Xiangyi; Yao, Manwen; Yang, Yucong; Li, Junfeng; Liu, Hongjun; Wang, Linyu

2016-02-01

Direct competitive chemiluminescence immunoassays (CLIA) based on gold-coated magnetic nanospheres (Au-MNPs) were developed for rapid analysis of chloramphenicol (CAP). The Au-MNPs were modified with carboxyl groups and amino groups by 11-mercaptoundecanoic acid (MUA) and cysteamine respectively, and then were respectively conjugated with CAP base and CAP succinate via an activating reaction using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS). NSP-DMAE-NHS, a new and effective luminescence reagent, was employed to label anti-CAP antibody (mAb) as a tracer in direct CLIA for CAP detection using a 'homemade' luminescent measurement system that was set up with a photomultiplier tube (PMT) and a photon counting unit linked to a computer. The sensitivities and limits of detection (LODs) of the two methods were obtained and compared according to the inhibition curves. The 50% inhibition concentration (IC50 ) values of the two methods were about 0.044 ng/mL and 0.072 ng/mL respectively and LODs were approximately 0.001 ng/mL and 0.006 ng/mL respectively. To our knowledge, they were much more sensitive than any traditional enzyme-linked immunosorbent assay (ELISA) ever reported. Moreover, the new luminescence reagent NSP-DMAE-NHS is much more sensitive and stable than luminol and its derivatives, contributing to the sensitivity enhancement. Copyright © 2015 John Wiley & Sons, Ltd.

JPRS Report. Soviet Union: World Economy & International Relations, No. 6, June 1987

DTIC Science & Technology

1987-09-23

Komsomol Congress, "is connected with the development of the mechanics of competitiveness in the economy, science and cultural life, a broadening of self... competitive selection and election. The process of democratization demands that the direct participation of the working people in the process of... Competition , intensified in the soil of S&T progress, is hitting the laggards even more ruthlessly." This conclusion is borne out convincingly by the

Automatic Detection of Pitching and Throwing Events in Baseball With Inertial Measurement Sensors.

PubMed

Murray, Nick B; Black, Georgia M; Whiteley, Rod J; Gahan, Peter; Cole, Michael H; Utting, Andy; Gabbett, Tim J

2017-04-01

Throwing loads are known to be closely related to injury risk. However, for logistic reasons, typically only pitchers have their throws counted, and then only during innings. Accordingly, all other throws made are not counted, so estimates of throws made by players may be inaccurately recorded and underreported. A potential solution to this is the use of wearable microtechnology to automatically detect, quantify, and report pitch counts in baseball. This study investigated the accuracy of detection of baseball pitching and throwing in both practice and competition using a commercially available wearable microtechnology unit. Seventeen elite youth baseball players (mean ± SD age 16.5 ± 0.8 y, height 184.1 ± 5.5 cm, mass 78.3 ± 7.7 kg) participated in this study. Participants performed pitching, fielding, and throwing during practice and competition while wearing a microtechnology unit. Sensitivity and specificity of a pitching and throwing algorithm were determined by comparing automatic measures (ie, microtechnology unit) with direct measures (ie, manually recorded pitching counts). The pitching and throwing algorithm was sensitive during both practice (100%) and competition (100%). Specificity was poorer during both practice (79.8%) and competition (74.4%). These findings demonstrate that the microtechnology unit is sensitive to detect pitching and throwing events, but further development of the pitching algorithm is required to accurately and consistently quantify throwing loads using microtechnology.

Diversity and relatedness enhance survival in colour polymorphic grasshoppers.

PubMed

Caesar, Sofia; Karlsson, Magnus; Forsman, Anders

2010-05-28

Evolutionary theory predicts that different resource utilization and behaviour by alternative phenotypes may reduce competition and enhance productivity and individual performance in polymorphic, as compared with monomorphic, groups of individuals. However, firm evidence that members of more heterogeneous groups benefit from enhanced survival has been scarce or lacking. Furthermore, benefits associated with phenotypic diversity may be counterbalanced by costs mediated by reduced relatedness, since closely related individuals typically are more similar. Pygmy grasshoppers (Tetrix subulata) are characterized by extensive polymorphism in colour pattern, morphology, behaviour and physiology. We studied experimental groups founded by different numbers of mothers and found that survival was higher in low than in high density, that survival peaked at intermediate colour morph diversity in high density, and that survival was independent of diversity in low density where competition was less intense. We further demonstrate that survival was enhanced by relatedness, as expected if antagonistic and competitive interactions are discriminately directed towards non-siblings. We therefore also performed behavioural observations and staged encounters which confirmed that individuals recognized and responded differently to siblings than to non-siblings. We conclude that negative effects associated with competition are less manifest in diverse groups, that there is conflicting selection for and against genetic diversity occurring simultaneously, and that diversity and relatedness may facilitate the productivity and ecological success of groups of interacting individuals.

Mechanistic Insights into Xenon Inhibition of NMDA Receptors from MD Simulations

PubMed Central

Liu, Lu Tian; Xu, Yan; Tang, Pei

2010-01-01

Inhibition of N-methyl-D-aspartate (NMDA) receptors has been viewed as a primary cause of xenon anesthesia, yet the mechanism is unclear. Here, we investigated interactions between xenon and the ligand-binding domain (LBD) of a NMDA receptor and examined xenon-induced structural and dynamical changes that are relevant to functional changes of the NMDA receptor. Several comparative molecular dynamics simulations were performed on two X-ray structures representing the open- and closed-cleft LBD of the NMDA receptor. We identified plausible xenon action sites in the LBD, including those nearby agonist sites, in the hinge region, and at the interface between two subunits. The xenon binding energy varies from −5.3 to −0.7 kcal/mol. Xenon's effect on the NMDA receptor is conformation-dependent and is produced through both competitive and non-competitive mechanisms. Xenon can promote cleft opening in the absence of agonists and consequently stabilizes the closed channel. Xenon can also bind at the interface of two subunits, alter the inter-subunit interaction, and lead to a reduction of the distance between GT-links. This reduction corresponds to a rearrangement of the channel toward a direction of pore size decreasing, implying a closed or desensitized channel. In addition to these non-competitive actions, xenon was found to weaken the glutamate binding, which could lead to low agonist efficacy and appear as competitive inhibition. PMID:20560662

Competition and primary care in the United States: separating fact from fancy.

PubMed

Siminoff, L

1986-01-01

Competitive strategies have been advocated as the solution for the economic ills of the U.S. economy. During the 1980s many economists and health care practitioners are arguing that a competitive strategy will bring down health care costs; these plans emphasize the existence of perverse incentives which reward cost reducing behavior with less revenue. Competitive strategies assume the existence of a "health care marketplace." Historically, the United States health care sector has not conformed to the ideal of the competitive market because of the special characteristics involved in the production and consumption of health care. Consumers have the least power in the health care sector and yet most competitive proposals are explicitly directed at changing consumer behavior, especially in the area of primary care. Much evidence indicates that competitive plans inhibit consumers from using primary care services, increase long-term health care costs, and ultimately require more government regulatory action.

The Effects of Incentives in Acquisition Competition on Program Outcomes

DTIC Science & Technology

2012-06-01

organizational, management, and cultural issues (Madachy, EFFECTS OF INCENTIVES IN ACQUISITION COMPETITION 5 2008, Frangos , 1998). In the SEI’s direct...change from the task force on defense acquisition law and oversight Forrester, J. W. (1971). Principles of systems. Pegasus Communications. Frangos , S

Strategic Thinking: The Untapped Resource for Leaders.

ERIC Educational Resources Information Center

Alfred, Richard L.

2001-01-01

Strategic thinking is an organized, analytical process by which college leaders can assess: (1) existing and potential competitors; (2) sources of competitive advantage; and (3) college capabilities and competitive position. Three outcomes of strategic thinking are: (1) clear institutional strategy and direction; (2) improved institutional…

NASA Heavy Lift Rotorcraft Systems Investigation

NASA Technical Reports Server (NTRS)

Johnson, Wayne; Yamauchi, Gloria K.; Watts, Michael E.

2005-01-01

The NASA Heavy Lift Rotorcraft Systems Investigation examined in depth several rotorcraft configurations for large civil transport, designed to meet the technology goals of the NASA Vehicle Systems Program. The investigation identified the Large Civil Tiltrotor as the configuration with the best potential to meet the technology goals. The design presented was economically competitive, with the potential for substantial impact on the air transportation system. The keys to achieving a competitive aircraft were low drag airframe and low disk loading rotors; structural weight reduction, for both airframe and rotors; drive system weight reduction; improved engine efficiency; low maintenance design; and manufacturing cost comparable to fixed-wing aircraft. Risk reduction plans were developed to provide the strategic direction to support a heavy-lift rotorcraft development. The following high risk areas were identified for heavy lift rotorcraft: high torque, light weight drive system; high performance, structurally efficient rotor/wing system; low noise aircraft; and super-integrated vehicle management system.

Designs and Technology Requirements for Civil Heavy Lift Rotorcraft

NASA Technical Reports Server (NTRS)

Johnson, Wayne; Yamauchi, Gloria K.; Watts, Michael E.

2006-01-01

The NASA Heavy Lift Rotorcraft Systems Investigation examined in depth several rotorcraft configurations for large civil transport, designed to meet the technology goals of the NASA Vehicle Systems Program. The investigation identified the Large Civil Tiltrotor as the configuration with the best potential to meet the technology goals. The design presented was economically competitive, with the potential for substantial impact on the air transportation system. The keys to achieving a competitive aircraft were low drag airframe and low disk loading rotors; structural weight reduction, for both airframe and rotors; drive system weight reduction; improved engine efficiency; low maintenance design; and manufacturing cost comparable to fixed-wing aircraft. Risk reduction plans were developed to provide the strategic direction to support a heavy-lift rotorcraft development. The following high risk areas were identified for heavy lift rotorcraft: high torque, light weight drive system; high performance, structurally efficient rotor/wing system; low noise aircraft; and super-integrated vehicle management system.

Demolishing the competition: the longitudinal link between competitive video games, competitive gambling, and aggression.

PubMed

Adachi, Paul J C; Willoughby, Teena

2013-07-01

The majority of research on the link between video games and aggression has focused on the violent content in games. In contrast, recent experimental research suggests that it is video game competition, not violence, that has the greatest effect on aggression in the short-term. However, no researchers have examined the long-term relationship between video game competition and aggression. In addition, if competition in video games is a significant reason for the link between video game play and aggression, then other competitive activities, such as competitive gambling, also may predict aggression over time. In the current study, we directly assessed the socialization (competitive video game play and competitive gambling predicts aggression over time) versus selection hypotheses (aggression predicts competitive video game play and competitive gambling over time). Adolescents (N = 1,492, 50.8 % female) were surveyed annually from Grade 9 to Grade 12 about their video game play, gambling, and aggressive behaviors. Greater competitive video game play and competitive gambling predicted higher levels of aggression over time, after controlling for previous levels of aggression, supporting the socialization hypothesis. The selection hypothesis also was supported, as aggression predicted greater competitive video game play and competitive gambling over time, after controlling for previous competitive video game play and competitive gambling. Our findings, taken together with the fact that millions of adolescents play competitive video games every day and that competitive gambling may increase as adolescents transition into adulthood, highlight the need for a greater understanding of the relationship between competition and aggression.

c-Myc-Dependent Cell Competition in Human Cancer Cells.

PubMed

Patel, Manish S; Shah, Heta S; Shrivastava, Neeta

2017-07-01

Cell Competition is an interaction between cells for existence in heterogeneous cell populations of multicellular organisms. This phenomenon is involved in initiation and progression of cancer where heterogeneous cell populations compete directly or indirectly for the survival of the fittest based on differential gene expression. In Drosophila, cells having lower dMyc expression are eliminated by cell competition through apoptosis when present in the milieu of cells having higher dMyc expression. Thus, we designed a study to develop c-Myc (human homolog) dependent in vitro cell competition model of human cancer cells. Cells with higher c-Myc were transfected with c-myc shRNA to prepare cells with lower c-Myc and then co-cultured with the same type of cells having a higher c-Myc in equal ratio. Cells with lower c-Myc showed a significant decrease in numbers when compared with higher c-Myc cells, suggesting "loser" and "winner" status of cells, respectively. During microscopy, engulfment of loser cells by winner cells was observed with higher expression of JNK in loser cells. Furthermore, elimination of loser cells was prevented significantly, when co-cultured cells were treated with the JNK (apoptosis) inhibitor. Above results indicate elimination of loser cells in the presence of winner cells by c-Myc-dependent mechanisms of cell competition in human cancer cells. This could be an important mechanism in human tumors where normal cells are eliminated by c-Myc-overexpressed tumor cells. J. Cell. Biochem. 118: 1782-1791, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

U.S. masters track participation reveals a stable sex difference in competitiveness.

PubMed

Deaner, Robert O; Addona, Vittorio; Mead, Michael P

2014-10-06

It is well established that men are more likely than women to engage in direct competition, but it is unclear if this reflects social structural conditions or evolved predispositions. These hypotheses can be addressed by quantifying competitiveness in sports and testing if the sex difference is decreasing over time in the U.S., a society where social roles have converged. Study 1 assessed participation and the occurrence of relatively fast performances by masters runners (40-74 years old) at recent road races and track meets. Fast performances occurred over 20 times more often at track meets than at road races. Women comprised 55% of finishers at roads races but only 15-28% of finishers at track meets. Thus, the sex difference in masters track participation can serve as a measure of the sex difference in competitiveness. Study 2 used data from national championship meets and yearly rankings lists to test whether the sex difference in masters track participation decreased from 1988-2012. The sex difference decreased overall, but there was no evidence of change since the late 1990s. Therefore, the sex difference in the willingness to engage in direct sports competition appears to reflect both social structural conditions and evolved predispositions.

Response repetition biases in human perceptual decisions are explained by activity decay in competitive attractor models

PubMed Central

Bonaiuto, James J; de Berker, Archy; Bestmann, Sven

2016-01-01

Animals and humans have a tendency to repeat recent choices, a phenomenon known as choice hysteresis. The mechanism for this choice bias remains unclear. Using an established, biophysically informed model of a competitive attractor network for decision making, we found that decaying tail activity from the previous trial caused choice hysteresis, especially during difficult trials, and accurately predicted human perceptual choices. In the model, choice variability could be directionally altered through amplification or dampening of post-trial activity decay through simulated depolarizing or hyperpolarizing network stimulation. An analogous intervention using transcranial direct current stimulation (tDCS) over left dorsolateral prefrontal cortex (dlPFC) yielded a close match between model predictions and experimental results: net soma depolarizing currents increased choice hysteresis, while hyperpolarizing currents suppressed it. Residual activity in competitive attractor networks within dlPFC may thus give rise to biases in perceptual choices, which can be directionally controlled through non-invasive brain stimulation. DOI: http://dx.doi.org/10.7554/eLife.20047.001 PMID:28005007

Diversity Increases Indirect Interactions, Attenuates the Intensity of Competition, and Promotes Coexistence.

PubMed

Aschehoug, Erik T; Callaway, Ragan M

2015-10-01

A fundamental assumption of coexistence theory is that competition inevitably decreases species diversity. Consequently, in the quest to understand the ecological regulators of diversity, there has been a great deal of focus on processes with the potential to reduce competitive exclusion. However, the notion that competition must decrease diversity is largely based on the outcome of two-species interaction experiments and models, despite the fact that species rarely interact only in pairs in natural systems. In a field experiment, we found that competition among native perennial plants in multispecies assemblages was far weaker than competition between those same species in pairwise arrangements and that indirect interactions appeared to weaken direct competitive effects. These results suggest that community assembly theory based on pairwise approaches may overestimate the strength of competition and likelihood of competitive exclusion in species-rich communities. We also found that Centaurea stoebe, a North American invader, retained strong competitive effects when competing against North American natives in both pairwise and multispecies assemblages. Our experimental results support an emerging body of theory suggesting that complex networks of competing species may generate strong indirect interactions that can maintain diversity and that ecological differentiation may not be necessary to attenuate competition.

The effects of competition on medical service provision.

PubMed

Brosig-Koch, Jeannette; Hehenkamp, Burkhard; Kokot, Johanna

2017-12-01

We explore how competition between physicians affects medical service provision. Previous research has shown that, without competition, physicians deviate from patient-optimal treatment under payment systems like capitation and fee-for-service. Although competition might reduce these distortions, physicians usually interact with each other repeatedly over time and only a fraction of patients switches providers at all. Both patterns might prevent competition to work in the desired direction. To analyze the behavioral effects of competition, we develop a theoretical benchmark that is then tested in a controlled laboratory experiment. Experimental conditions vary physician payment and patient characteristics. Real patients benefit from provision decisions made in the experiment. Our results reveal that, in line with the theoretical prediction, introducing competition can reduce overprovision and underprovision, respectively. The observed effects depend on patient characteristics and the payment system, though. Tacit collusion is observed and particularly pronounced with fee-for-service payment, but it appears to be less frequent than in related experimental research on price competition. Copyright © 2017 John Wiley & Sons, Ltd.

Non-additive effects of intra- and interspecific competition between two larval salamanders.

PubMed

Anderson, Thomas L; Whiteman, Howard H

2015-05-01

Assessment of the relative strengths of intra- and interspecific competition has increased in recent years and is critical to understanding the importance of competition. Yet, whether intra- and interspecific competition can have non-additive effects has rarely been tested. The resulting fitness consequences of such non-additive interactions are important to provide the context necessary to advance our understanding of competition theory. We compared the strength of additive and non-additive intra- and interspecific competition by manipulating densities of a pair of larval salamanders (Ambystoma talpoideum and A. maculatum) in experimental mesocosms within a response surface design. Intraspecific density had the strongest effect on the strength of competition for both species, and few observed comparisons indicated interspecific competition was an important factor in predicting body size, growth or larval period length of either species. Non-additive effects of intra- and interspecific competition influenced some response variables, including size and mass at metamorphosis in A. maculatum, but at a reduced strength compared to intraspecific effects alone. Intraspecific competition was thus the dominant biotic interaction, but non-additive effects also impact the outcome of competition in these species, validating the importance of testing for and incorporating non-additive density effects into competition models. © 2015 The Authors. Journal of Animal Ecology © 2015 British Ecological Society.

Aggress to impress: hostility as an evolved context-dependent strategy.

PubMed

Griskevicius, Vladas; Tybur, Joshua M; Gangestad, Steven W; Perea, Elaine F; Shapiro, Jenessa R; Kenrick, Douglas T

2009-05-01

Given the high costs of aggression, why have people evolved to act aggressively? Comparative biologists have frequently observed links between aggression, status, and mating in nonhuman animals. In this series of experiments, the authors examined the effects of status, competition, and mating motives on men's and women's aggression. For men, status motives increased direct aggression (face-to-face confrontation). Men's aggression was also boosted by mating motives, but only when observers were other men. For women, both status and mating motives increased indirect aggression (e.g., socially excluding the perpetrator). Although neither status nor mating motives increased women's direct aggression, women did become more directly aggressive when motivated to compete for scarce resources. These context- and sex-specific effects on human aggression contribute to a broader understanding of the functional nature of aggressive behavior. Copyright (c) 2009 APA, all rights reserved.

Directional Solidification and Mechanical Properties of NiAl-NiAlTa Alloys

NASA Technical Reports Server (NTRS)

Johnson, D. R.; Chen, X. F.; Oliver, B. F.; Noebe, R. D.; Whittenberger, J. D.

1995-01-01

Directional solidification of eutectic alloys is a promising technique for producing in-situ composite materials exhibiting a balance of properties. Consequently, the microstructure, creep strength and fracture toughness of directionally solidified NiAl-NiAlTa alloys were investigated. Directional solidification was performed by containerless processing techniques to minimize alloy contamination. The eutectic composition was found to be NiAl-15.5 at% Ta and well-aligned microstructures were produced at this composition. A near-eutectic alloy of NiAl-14.5Ta was also investigated. Directional solidification of the near-eutectic composition resulted in microstructures consisting of NiAl dendrites surrounded by aligned eutectic regions. The off-eutectic alloy exhibited promising compressive creep strengths compared to other NiAl-based intermetallics, while preliminary testing indicated that the eutectic alloy was competitive with Ni-base single crystal superalloys. The room temperature toughness of these two-phase alloys was similar to that of polycrystalline NiAl even with the presence of the brittle Laves phase NiAlTa.

Phenotypic response of plants to simulated climate change in a long-term rain-manipulation experiment: a multi-species study.

PubMed

Hänel, Sabine; Tielbörger, Katja

2015-04-01

Many species will need to adapt to the observed climate change in order to persist. However, research about adaptation or phenotypic plasticity in response to climate change is rare. In particular, field studies are lacking that impose artificial selection for a sufficiently long time to elicit changes in phenotypic and genotypic structure of populations. Here, we present findings for an 8-year field experiment with 16 annual plant species that tested potentially adaptive phenotypic responses to precipitation change. In both a Mediterranean and a semi-arid site, annual precipitation was manipulated (±30%) and phenotypic response was recorded. We measured flowering time as a key trait related to climatic conditions and biomass and survival as fitness correlates. Differences in traits among treatments were compared to trait shifts between sites, according to space-for-time approaches. In the drier site, phenology was accelerated, but within that site, experimental drought delayed phenology, probably as a plastic response to delayed ontogenetic development. Biomass was smaller in the dry treatments of that site, but it was also reduced in irrigated plots in both sites, indicating more intense competition. The shifts from limitation by drought to limitation by competition corresponded to patterns along the gradient. This also implies a larger negative impact of climate change in the drier site. Our results suggest that experimental selection in the field caused directional responses in most species, but these were not necessarily adaptive. Furthermore, competitive release imposed by climate change may revert direct negative effects of rainfall change in determining plant performance.

Modeling effects of intrinsic and extrinsic rewards on the competition between striatal learning systems.

PubMed

Boedecker, Joschka; Lampe, Thomas; Riedmiller, Martin

2013-01-01

A common assumption in psychology, economics, and other fields holds that higher performance will result if extrinsic rewards (such as money) are offered as an incentive. While this principle seems to work well for tasks that require the execution of the same sequence of steps over and over, with little uncertainty about the process, in other cases, especially where creative problem solving is required due to the difficulty in finding the optimal sequence of actions, external rewards can actually be detrimental to task performance. Furthermore, they have the potential to undermine intrinsic motivation to do an otherwise interesting activity. In this work, we extend a computational model of the dorsomedial and dorsolateral striatal reinforcement learning systems to account for the effects of extrinsic and intrinsic rewards. The model assumes that the brain employs both a goal-directed and a habitual learning system, and competition between both is based on the trade-off between the cost of the reasoning process and value of information. The goal-directed system elicits internal rewards when its models of the environment improve, while the habitual system, being model-free, does not. Our results account for the phenomena that initial extrinsic reward leads to reduced activity after extinction compared to the case without any initial extrinsic rewards, and that performance in complex task settings drops when higher external rewards are promised. We also test the hypothesis that external rewards bias the competition in favor of the computationally efficient, but cruder and less flexible habitual system, which can negatively influence intrinsic motivation and task performance in the class of tasks we consider.

How does male–male competition generate negative frequency-dependent selection and disruptive selection during speciation?

PubMed Central

Border, Shana E

2018-01-01

Abstract Natural selection has been shown to drive population differentiation and speciation. The role of sexual selection in this process is controversial; however, most of the work has centered on mate choice while the role of male–male competition in speciation is relatively understudied. Here, we outline how male–male competition can be a source of diversifying selection on male competitive phenotypes, and how this can contribute to the evolution of reproductive isolation. We highlight how negative frequency-dependent selection (advantage of rare phenotype arising from stronger male–male competition between similar male phenotypes compared with dissimilar male phenotypes) and disruptive selection (advantage of extreme phenotypes) drives the evolution of diversity in competitive traits such as weapon size, nuptial coloration, or aggressiveness. We underscore that male–male competition interacts with other life-history functions and that variable male competitive phenotypes may represent alternative adaptive options. In addition to competition for mates, aggressive interference competition for ecological resources can exert selection on competitor signals. We call for a better integration of male–male competition with ecological interference competition since both can influence the process of speciation via comparable but distinct mechanisms. Altogether, we present a more comprehensive framework for studying the role of male–male competition in speciation, and emphasize the need for better integration of insights gained from other fields studying the evolutionary, behavioral, and physiological consequences of agonistic interactions. PMID:29492042

Exogenous testosterone in women enhances and inhibits competitive decision-making depending on victory-defeat experience and trait dominance.

PubMed

Mehta, Pranjal H; van Son, Veerle; Welker, Keith M; Prasad, Smrithi; Sanfey, Alan G; Smidts, Ale; Roelofs, Karin

2015-10-01

The present experiment tested the causal impact of testosterone on human competitive decision-making. According to prevailing theories about testosterone's role in social behavior, testosterone should directly boost competitive decisions. But recent correlational evidence suggests that testosterone's behavioral effects may depend on specific aspects of the context and person relevant to social status (win-lose context and trait dominance). We tested the causal influence of testosterone on competitive decisions by combining hormone administration with measures of trait dominance and a newly developed social competition task in which the victory-defeat context was experimentally manipulated, in a sample of 54 female participants. Consistent with the hypothesis that testosterone has context- and person-dependent effects on competitive behavior, testosterone increased competitive decisions after victory only among high-dominant individuals but testosterone decreased competitive decisions after defeat across all participants. These results suggest that testosterone flexibly modulates competitive decision-making depending on prior social experience and dominance motivation in the service of enhancing social status. Copyright © 2015 Elsevier Ltd. All rights reserved.

Competitive negotiation: the Virginia SCC's model for procurement of generating capacity

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

Not Available

The Virginia SCC, in approving competitive alternatives to avoided costs under PURPA, rejected competitive bidding in favor of competitive negotiation for power sales contracts. The difference is important, and points in the direction of increased discretion for utilities seeking new generating capacity from independents. The distinction between competitive bidding, and competitive negotiation, in a nutshell, is that in a bid, the low price bidder wins. In a negotiation, the offeror of the most-meritorious proposals are ranked, and an attempt to reach agreement on price is made with the high-ranked offeror. Only if there is no agreement on price will themore » most-meritorious bid be rejected, and negotiations with the offeror of the next best proposal begun. The Virginia Public Procurement Act, Sec. II-37, Definitions, Parts 1, 2, and 3.a. is included.« less

Patterns of fruit and vegetable availability and price competitiveness across four seasons are different in local food outlets and supermarkets.

PubMed

Valpiani, Natalie; Wilde, Parke; Rogers, Beatrice; Stewart, Hayden

2015-10-01

To explore the effect of seasonality on fruit and vegetable availability and prices across three outlet types (farmers' markets, roadside stands and conventional supermarkets). Cross-sectional survey of geographically clustered supermarkets, farmers' markets and roadside stands. Enumerators recorded the availability and lowest price for eleven fruits and eighteen vegetables in each season of 2011. Price data were collected at retail outlets located in central and eastern North Carolina. The sample consisted of thirty-three supermarkets, thirty-four farmers' markets and twenty-three roadside stands. Outside the local harvest season, the availability of many fruits and vegetables was substantially lower at farmers' markets and roadside stands compared with supermarkets. Given sufficient availability, some items were significantly cheaper (P<0·05) at direct retail outlets in the peak season (e.g. cantaloupe cost 36·0 % less at roadside stands than supermarkets), while others were significantly more expensive (e.g. carrots cost 137·9 % more at farmers' markets than supermarkets). Although small samples limited statistical power in many non-peak comparisons, these results also showed some differences by item: two-thirds of fruits were cheaper at one or both direct outlets in the spring and autumn, whereas five of eighteen vegetables cost more at direct retail year-round. Commonly consumed fruits and vegetables were more widely available at supermarkets in central and eastern North Carolina than at direct retail outlets, in each season. Contingent on item availability, price competitiveness of the direct retail outlets varied by fruit and vegetable. For many items, the outlets compete on price in more than one season.

A Novel Method for Analyzing Extremely Biased Agonism at G Protein–Coupled Receptors

PubMed Central

Zhou, Lei; Ehlert, Frederick J.; Bohn, Laura M.

2015-01-01

Seven transmembrane receptors were originally named and characterized based on their ability to couple to heterotrimeric G proteins. The assortment of coupling partners for G protein–coupled receptors has subsequently expanded to include other effectors (most notably the βarrestins). This diversity of partners available to the receptor has prompted the pursuit of ligands that selectively activate only a subset of the available partners. A biased or functionally selective ligand may be able to distinguish between different active states of the receptor, and this would result in the preferential activation of one signaling cascade more than another. Although application of the “standard” operational model for analyzing ligand bias is useful and suitable in most cases, there are limitations that arise when the biased agonist fails to induce a significant response in one of the assays being compared. In this article, we describe a quantitative method for measuring ligand bias that is particularly useful for such cases of extreme bias. Using simulations and experimental evidence from several κ opioid receptor agonists, we illustrate a “competitive” model for quantitating the degree and direction of bias. By comparing the results obtained from the competitive model with the standard model, we demonstrate that the competitive model expands the potential for evaluating the bias of very partial agonists. We conclude the competitive model provides a useful mechanism for analyzing the bias of partial agonists that exhibit extreme bias. PMID:25680753

Quantitative inhibition of soil C and N cycling by ectomycorrhizal fungi under field condition

NASA Astrophysics Data System (ADS)

Averill, C.; Hawkes, C.

2014-12-01

Ectomycorrhizal (ECM) ecosystems store more carbon than non-ectomycorrhizal ecosystems at global scale. Recent theoretical and empirical work suggests the presence of ECM fungi allows plants to compete directly with decomposers for soil nitrogen (N) via exo-enzyme synthesis. Experimental ECM exclusion often results in a release from competition of saprotrophic decomposers, allowing for increased C-degrading enzyme production, increased microbial biomass, and eventually declines in soil C stocks. Our knowledge of this phenomenon is limited, however, to the presence or absence of ECM fungi. It remains unknown if competitive repression of saprotrophic microbes and soil C cycling by ECM fungi varies with ECM abundance. This is particularly relevant to global change experiments when manipulations alter plant C allocation to ECM symbionts. To test if variation in ECM abundance alters the competitive inhibition of saprotrophic soil microbes (quantitative inhibition) we established experimental ECM exclusion treatments along an ECM abundance gradient. We dug trenches to experimentally exclude ECM fungi, allowing us to test for competitive release of soil saprotrophs from competition. To control for disturbance we placed in-growth bags both inside and outside of trenches. Consistent with the quantitative inhibition hypothesis, sites with more ECM fungi had significantly less microbial biomass per unit soil C and lower rates of N mineralization. Consistent with a release from competition, C-degrading enzyme activities were higher and gross proteolytic rates were lower per unit microbial biomass inside compared to outside trenches. We interpret this to reflect increased microbial investment in C-acquisition and decreased investment in N-acquisition in the absence of ECM fungi. Furthermore, the increase in C-degrading enzymes per unit microbial biomass was significantly greater in sites with the most abundant ECM fungi. Based on these results, ECM-saprotroph competition does appear to slow soil C cycling and the effect is quantitative. Soil C cycling is at least partly controlled by interactions between ECM fungi and soil saprotrophs. Environmental change that alters ECM abundance may thus alter soil C stocks by ameliorating or exacerbating plant-decomposer competition for nitrogen.

An Exploration of Open Innovation: An Environmental Scanning Perspective

ERIC Educational Resources Information Center

Elci, Nuray

2009-01-01

Globalization and direction toward a knowledge economy, along with an economic downturn, is creating a competitive environment that calls for corporations to become more innovative. As the business environment becomes more competitive and dynamic, corporations are looking for new ways of achieving innovation. Open innovation is one approach that…

75 FR 42783 - Notice of Receipt of Complaint; Solicitation of Comments Relating to the Public Interest

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-22

... Re Certain Flat Panel Digital Televisions and Components Thereof''; the Commission is soliciting... importation of certain flat panel digital televisions and components thereof. The complaint names as..., competitive conditions in the United States economy, the production of like or directly competitive articles...

Assimilation, Ethnic Competition, and Ethnic Identities of U.S.-Born Persons of Mexican Origin.

ERIC Educational Resources Information Center

Ono, Hiromi

2002-01-01

Explores processes governing the ethnic identification of second and later generations of Mexican immigrant descendants using the Latino National Political Survey. Ethnic identification arises directly from cultural continuity and lower levels of assimilation, experiences with ethnic competition, and a combination of both processes. Experiences…

43 CFR 2932.31 - How does BLM establish fees for Special Recreation Permits?

Code of Federal Regulations, 2012 CFR

2012-10-01

... RECREATION ON PUBLIC LANDS Special Recreation Permits for Commercial Use, Competitive Events, Organized... Permits for commercial activities, organized group activities or events, and competitive events. (b) The... following types of data: (1) The direct and indirect cost to the government; (2) The types of services or...

43 CFR 2932.31 - How does BLM establish fees for Special Recreation Permits?

Code of Federal Regulations, 2013 CFR

2013-10-01

... RECREATION ON PUBLIC LANDS Special Recreation Permits for Commercial Use, Competitive Events, Organized... Permits for commercial activities, organized group activities or events, and competitive events. (b) The... following types of data: (1) The direct and indirect cost to the government; (2) The types of services or...

43 CFR 2932.31 - How does BLM establish fees for Special Recreation Permits?

Code of Federal Regulations, 2014 CFR

2014-10-01

... RECREATION ON PUBLIC LANDS Special Recreation Permits for Commercial Use, Competitive Events, Organized... Permits for commercial activities, organized group activities or events, and competitive events. (b) The... following types of data: (1) The direct and indirect cost to the government; (2) The types of services or...

43 CFR 2932.31 - How does BLM establish fees for Special Recreation Permits?

Code of Federal Regulations, 2011 CFR

2011-10-01

... RECREATION ON PUBLIC LANDS Special Recreation Permits for Commercial Use, Competitive Events, Organized... Permits for commercial activities, organized group activities or events, and competitive events. (b) The... following types of data: (1) The direct and indirect cost to the government; (2) The types of services or...

7 CFR 1435.605 - Competitive procedures.

Code of Federal Regulations, 2014 CFR

2014-01-01

... § 1435.605 Competitive procedures. (a) CCC will generally issue tenders for bids, before entering into... the least cost to CCC of removing sugar from the market. (b) CCC may, at times, negotiate contracts directly with sellers or buyers, if CCC determines that such negotiation will result in either reduced...

Competition between multiple words for a referent in cross-situational word learning

PubMed Central

Benitez, Viridiana L.; Yurovsky, Daniel; Smith, Linda B.

2016-01-01

Three experiments investigated competition between word-object pairings in a cross-situational word-learning paradigm. Adults were presented with One-Word pairings, where a single word labeled a single object, and Two-Word pairings, where two words labeled a single object. In addition to measuring learning of these two pairing types, we measured competition between words that refer to the same object. When the word-object co-occurrences were presented intermixed in training (Experiment 1), we found evidence for direct competition between words that label the same referent. Separating the two words for an object in time eliminated any evidence for this competition (Experiment 2). Experiment 3 demonstrated that adding a linguistic cue to the second label for a referent led to different competition effects between adults who self-reported different language learning histories, suggesting both distinctiveness and language learning history affect competition. Finally, in all experiments, competition effects were unrelated to participants’ explicit judgments of learning, suggesting that competition reflects the operating characteristics of implicit learning processes. Together, these results demonstrate that the role of competition between overlapping associations in statistical word-referent learning depends on time, the distinctiveness of word-object pairings, and language learning history. PMID:27087742

Are invasive plants more competitive than native conspecifics? Patterns vary with competitors

NASA Astrophysics Data System (ADS)

Zheng, Yulong; Feng, Yulong; Valiente-Banuet, Alfonso; Li, Yangping; Liao, Zhiyong; Zhang, Jiaolin; Chen, Yajun

2015-10-01

Invasive plants are sometimes considered to be more competitive than their native conspecifics, according to the prediction that the invader reallocates resources from defense to growth due to liberation of natural enemies [‘Evolution of Increased Competitive Ability’ (EICA) hypothesis]. However, the differences in competitive ability may depend on the identity of competitors. In order to test the effects of competitors, Ageratina adenophora plants from both native and invasive ranges competed directly, and competed with native residents from both invasive (China) and native (Mexico) ranges respectively. Invasive A. adenophora plants were more competitive than their conspecifics from native populations when competing with natives from China (interspecific competition), but not when competing with natives from Mexico. Invasive A. adenophora plants also showed higher competitive ability when grown in high-density monoculture communities of plants from the same population (intrapopulation competition). In contrast, invasive A. adenophora plants showed lower competitive ability when competing with plants from native populations (intraspecific competition). Our results indicated that in the invasive range A. adenophora has evolved to effectively cope with co-occurring natives and high density environments, contributing to invasion success. Here, we showed the significant effects of competitors, which should be considered carefully when testing the EICA hypothesis.

Are invasive plants more competitive than native conspecifics? Patterns vary with competitors.

PubMed

Zheng, Yulong; Feng, Yulong; Valiente-Banuet, Alfonso; Li, Yangping; Liao, Zhiyong; Zhang, Jiaolin; Chen, Yajun

2015-10-22

Invasive plants are sometimes considered to be more competitive than their native conspecifics, according to the prediction that the invader reallocates resources from defense to growth due to liberation of natural enemies ['Evolution of Increased Competitive Ability' (EICA) hypothesis]. However, the differences in competitive ability may depend on the identity of competitors. In order to test the effects of competitors, Ageratina adenophora plants from both native and invasive ranges competed directly, and competed with native residents from both invasive (China) and native (Mexico) ranges respectively. Invasive A. adenophora plants were more competitive than their conspecifics from native populations when competing with natives from China (interspecific competition), but not when competing with natives from Mexico. Invasive A. adenophora plants also showed higher competitive ability when grown in high-density monoculture communities of plants from the same population (intrapopulation competition). In contrast, invasive A. adenophora plants showed lower competitive ability when competing with plants from native populations (intraspecific competition). Our results indicated that in the invasive range A. adenophora has evolved to effectively cope with co-occurring natives and high density environments, contributing to invasion success. Here, we showed the significant effects of competitors, which should be considered carefully when testing the EICA hypothesis.

Optimization of controllability and robustness of complex networks by edge directionality

NASA Astrophysics Data System (ADS)

Liang, Man; Jin, Suoqin; Wang, Dingjie; Zou, Xiufen

2016-09-01

Recently, controllability of complex networks has attracted enormous attention in various fields of science and engineering. How to optimize structural controllability has also become a significant issue. Previous studies have shown that an appropriate directional assignment can improve structural controllability; however, the evolution of the structural controllability of complex networks under attacks and cascading has always been ignored. To address this problem, this study proposes a new edge orientation method (NEOM) based on residual degree that changes the link direction while conserving topology and directionality. By comparing the results with those of previous methods in two random graph models and several realistic networks, our proposed approach is demonstrated to be an effective and competitive method for improving the structural controllability of complex networks. Moreover, numerical simulations show that our method is near-optimal in optimizing structural controllability. Strikingly, compared to the original network, our method maintains the structural controllability of the network under attacks and cascading, indicating that the NEOM can also enhance the robustness of controllability of networks. These results alter the view of the nature of controllability in complex networks, change the understanding of structural controllability and affect the design of network models to control such networks.

Competitive interactions between native and invasive exotic plant species are altered under elevated carbon dioxide.

PubMed

Manea, Anthony; Leishman, Michelle R

2011-03-01

We hypothesized that the greater competitive ability of invasive exotic plants relative to native plants would increase under elevated CO(2) because they typically have traits that confer the ability for fast growth when resources are not limiting and thus are likely to be more responsive to elevated CO(2). A series of competition experiments under ambient and elevated CO(2) glasshouse conditions were conducted to determine an index of relative competition intensity for 14 native-invasive exotic species-pairs. Traits including specific leaf area, leaf mass ratio, leaf area ratio, relative growth rate, net assimilation rate and root weight ratio were measured. Competitive rankings within species-pairs were not affected by CO(2) concentration: invasive exotic species were more competitive in 9 of the 14 species-pairs and native species were more competitive in the remaining 5 species-pairs, regardless of CO(2) concentration. However, there was a significant interaction between plant type and CO(2) treatment due to reduced competitive response of native species under elevated compared with ambient CO(2) conditions. Native species had significantly lower specific leaf area and leaf area ratio under elevated compared with ambient CO(2). We also compared traits of more-competitive with less-competitive species, regardless of plant type, under both CO(2) treatments. More-competitive species had smaller leaf weight ratio and leaf area ratio, and larger relative growth rate and net assimilation rate under both ambient and elevated CO(2) conditions. These results suggest that growth and allocation traits can be useful predictors of the outcome of competitive interactions under both ambient and elevated CO(2) conditions. Under predicted future atmospheric CO(2) conditions, competitive rankings among species may not change substantially, but the relative success of invasive exotic species may be increased. Thus, under future atmospheric CO(2) conditions, the ecological and economic impact of some invasive exotic plants may be even greater than under current conditions.

Differential reward responses during competition against in- and out-of-network others

PubMed Central

Fareri, Dominic S.

2014-01-01

Social interactions occur within a variety of different contexts––cooperative/competitive––and often involve members of our social network. Here, we investigated whether social network modulated the value placed on positive outcomes during a competitive context. Eighteen human participants played a simple card-guessing game with three different competitors: a close friend (in-network), a confederate (out-of-network) and a random number generator (non-social condition) while undergoing functional magnetic resonance imaging. Neuroimaging results at the time of outcome receipt demonstrated a significant main effect of competitor across multiple regions of medial prefrontal cortex, with Blood Oxygen Level Dependent (BOLD) responses strongest when competing against one’s friend compared with all other conditions. Striatal BOLD responses demonstrated a more general sensitivity to positive compared with negative monetary outcomes, which an exploratory analysis revealed to be stronger when interacting with social, compared with non-social, competitors. Interestingly, a Granger causality analysis indicated directed influences sent from an medial prefrontal cortex (mPFC) region, which shows social network differentiation of outcomes, and the ventral striatum bilaterally. Our results suggest that when competing against others of varying degrees of social network, mPFC differentially values these outcomes, perhaps treating in-network outcomes as more informative, leaving the striatum to more general value computations. PMID:23314007

Sensing a heart infarction marker with surface plasmon resonance spectroscopy

NASA Astrophysics Data System (ADS)

Kunz, Ulrich; Katerkamp, Andreas; Renneberg, Reinhard; Spener, Friedrich; Cammann, Karl

1995-02-01

In this study a direct immunosensor for heart-type fatty acid binding protein (FABP) based on surface plasmon resonance spectroscopy (SPRS) is presented. FABP can be used as a heart infarction marker in clinical diagnostics. The development of a simple and cheap direct optical sensor device is reported in this paper as well as immobilization procedures and optimization of the measuring conditions. The correct working of the SPRS device is controlled by comparing the signals with theoretical calculated values. Two different immunoassay techniques were optimized for a sensitive FABP-analysis. The competitive immunoassay was superior to the sandwich configuration as it had a lower detection limit (100 ng/ml), needed less antibodies and could be carried out in one step.

Microscale Titration in Schools Titration Competition.

ERIC Educational Resources Information Center

Clark, Michael J.

1998-01-01

Reviews the requirements of the National Titration Competition and describes how a team in a local competition used the technique. Compares microscale titration to conventional titration. Outlines the benefits of employing microscale techniques. (DDR)

A change in competitive context reverses sexual selection on male size.

PubMed

Kasumovic, M M; Andrade, M C B

2009-02-01

In studies of sexual selection, larger size is often argued to increase male fitness, and relatively smaller males are explained by genetic and/or environmental variation. We demonstrate that a size-development life-history trade-off could underlie the maintenance of a broad, unimodal distribution of size in male redback spiders (Latrodectus hasselti). Larger males are superior in direct competition, but redback males mature rapidly at small size in the presence of females. In field enclosures, we simulated two competitive contexts favouring development of divergent male sizes. Relatively smaller males lost when competing directly, but had 10 times higher fitness than relatively larger males when given the temporal advantage of rapid development. Linear selection gradients confirmed the reversal of selection on size, showing that it is critical to consider life-history decisions underlying the development of traits related to fitness.

Sperm competition risk drives rapid ejaculate adjustments mediated by seminal fluid

PubMed Central

Steeves, Tammy E; Gemmell, Neil J; Rosengrave, Patrice C

2017-01-01

In many species, males can make rapid adjustments to ejaculate performance in response to sperm competition risk; however, the mechanisms behind these changes are not understood. Here, we manipulate male social status in an externally fertilising fish, chinook salmon (Oncorhynchus tshawytscha), and find that in less than 48 hr, males can upregulate sperm velocity when faced with an increased risk of sperm competition. Using a series of in vitro sperm manipulation and competition experiments, we show that rapid changes in sperm velocity are mediated by seminal fluid and the effect of seminal fluid on sperm velocity directly impacts paternity share and therefore reproductive success. These combined findings, completely consistent with sperm competition theory, provide unequivocal evidence that sperm competition risk drives plastic adjustment of ejaculate quality, that seminal fluid harbours the mechanism for the rapid adjustment of sperm velocity and that fitness benefits accrue to males from such adjustment. PMID:29084621

Sperm competition risk drives rapid ejaculate adjustments mediated by seminal fluid.

PubMed

Bartlett, Michael J; Steeves, Tammy E; Gemmell, Neil J; Rosengrave, Patrice C

2017-10-31

In many species, males can make rapid adjustments to ejaculate performance in response to sperm competition risk; however, the mechanisms behind these changes are not understood. Here, we manipulate male social status in an externally fertilising fish, chinook salmon ( Oncorhynchus tshawytscha ), and find that in less than 48 hr, males can upregulate sperm velocity when faced with an increased risk of sperm competition. Using a series of in vitro sperm manipulation and competition experiments, we show that rapid changes in sperm velocity are mediated by seminal fluid and the effect of seminal fluid on sperm velocity directly impacts paternity share and therefore reproductive success. These combined findings, completely consistent with sperm competition theory, provide unequivocal evidence that sperm competition risk drives plastic adjustment of ejaculate quality, that seminal fluid harbours the mechanism for the rapid adjustment of sperm velocity and that fitness benefits accrue to males from such adjustment.

Are Competition and Extrinsic Motivation Reliable Predictors of Academic Cheating?

PubMed Central

Orosz, Gábor; Farkas, Dávid; Roland-Lévy, Christine

2013-01-01

Previous studies suggest that extrinsic motivation and competition are reliable predictors of academic cheating. The aim of the present questionnaire study was to separate the effects of motivation- and competition-related variables on academic cheating by Hungarian high school students (N = 620, M = 264, F = 356). Structural equation modeling showed that intrinsic motivation has a negative effect, and amotivation has a positive indirect effect on self-reported academic cheating. In contrast, extrinsic motivation had no significant effect. Indirect positive influence on cheating, based on some characteristics of hypercompetition, was also found, whereas attitudes toward self-developmental competition had a mediated negative influence. Neither constructive nor destructive competitive classroom climate had a significant impact on academic dishonesty. Acceptance of cheating and guilt has significant and direct effect on self-reported cheating. In comparison with them, the effects of motivational and competition-related variables are relatively small, even negligible. These results suggest that extrinsic motivation and competition are not amongst the most reliable predictors of academic cheating behavior. PMID:23450676

Are competition and extrinsic motivation reliable predictors of academic cheating?

PubMed

Orosz, Gábor; Farkas, Dávid; Roland-Lévy, Christine

2013-01-01

Previous studies suggest that extrinsic motivation and competition are reliable predictors of academic cheating. The aim of the present questionnaire study was to separate the effects of motivation- and competition-related variables on academic cheating by Hungarian high school students (N = 620, M = 264, F = 356). Structural equation modeling showed that intrinsic motivation has a negative effect, and amotivation has a positive indirect effect on self-reported academic cheating. In contrast, extrinsic motivation had no significant effect. Indirect positive influence on cheating, based on some characteristics of hypercompetition, was also found, whereas attitudes toward self-developmental competition had a mediated negative influence. Neither constructive nor destructive competitive classroom climate had a significant impact on academic dishonesty. Acceptance of cheating and guilt has significant and direct effect on self-reported cheating. In comparison with them, the effects of motivational and competition-related variables are relatively small, even negligible. These results suggest that extrinsic motivation and competition are not amongst the most reliable predictors of academic cheating behavior.

The influence of parenting practices and parental presence on children's and adolescents' pre-competitive anxiety.

PubMed

Bois, Julien E; Lalanne, Julien; Delforge, Catherine

2009-08-01

We examined parental influence on athletes' pre-competitive anxiety. The effect of parental presence during competition was studied as was the role of parenting practices. Data were collected from a sample of 341 athletes (201 basketball players and 140 tennis players) before an official competition. Analysis of variance indicated that the presence of both parents was associated with higher pre-competitive anxiety for all participants, except male tennis players. The absence of both parents did not result in less anxiety. A second analysis of variance revealed that females tennis players at provincial and national level perceived greater parental pressure than most other participants. Canonical correlation analysis showed a positive relationship between pre-competitive anxiety and parenting practices for tennis players, but not for basketball players. Directive behaviours and pressure were positively associated with pre-competitive anxiety for all tennis players, whereas praise and understanding was negatively related to anxiety for female tennis players only.

Actin dynamics in cells on nanotopographical surfaces in competition with chemotaxis and electrotaxis

NASA Astrophysics Data System (ADS)

Schmidt, Sebastian

Directed cell migration can be guided by different types of gradients, for example chemotaxis. We use surfaces with nanotopographical ridges to examine a type of guidance called esotaxis on migration in the well-studied amoeba Dictyostelium Discoideum. In this work we compare chemotaxis with esotaxis on ridges as well as the influence of electrotaxis on the formation of the actin cytoskeleton on these nanotopographies. These esotactic surfaces have more guidance cues for cells than planar 2D cultures and can disrupt other guidance types like chemotaxis.

Evolution of competitive ability within Lonicera japonica's invaded range

Treesearch

Gregory A. Evans; Francis F. Kilkenny; Laura F. Galloway

2013-01-01

Factors influencing invasive taxa may change during the course of an invasion. For example, intraspecific competition is predicted to be more important in areas with older stands of dense monospecific invaders than at the margins of an invaded range. We evaluated evolution in response to predicted changes in competition by comparing the intraspecific competitive...

Exploring the Competitive Effects of Charter Schools

ERIC Educational Resources Information Center

Carpenter, Dick M., II; Medina, Paul M.

2011-01-01

Central to the debate over school choice has been the question of how public schools respond to market-based competition. Many choice advocates suggest that competition can spur public schools to become more effective and efficient, but the evidence regarding the effect of competition from charters is comparably sparse and mixed. This article…

Body-esteem of pupils who attended single-sex versus mixed-sex schools: a cross-sectional study of intrasexual competition and peer victimization.

PubMed

Lereya, Suzet Tanya; Eryigit-Madzwamuse, Suna; Patra, Chanchala; Smith, Joshua H; Wolke, Dieter

2014-10-01

In intrasexual competition (competition for reproductive resources), bullying can be viewed as a tool to devalue competitors, gain a high status and a powerful, dominant position in the peer group which may lead to beneficial gains such as access to potential romantic partners. This study investigated the relationship between intrasexual competition, bullying victimization and body-esteem, in single-sex versus mixed-sex schools. 420 participants completed a body-esteem scale, a retrospective bullying questionnaire, and intrasexual competition scales. Our results showed that relational victimization was associated with low body-esteem for both females and males. Females in single-sex schools experienced higher intrasexual competition which in turn was associated with their body-esteem directly and indirectly via relational victimization. In males, intrasexual competition was indirectly associated with body-esteem via relational victimization. Interventions to improve body esteem may focus on reducing intrasexual competition and peer victimization. Copyright © 2014 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Mathematics and engineering in real life through mathematical competitions

NASA Astrophysics Data System (ADS)

More, M.

2018-02-01

We bring out an experience of organizing mathematical competitions that can be used as a medium to motivate the student and teacher minds in new directions of thinking. This can contribute to fostering research, innovation and provide a hands-on experience of mathematical concepts with the real world. Mathematical competitions can be used to build curiosity and give an understanding of mathematical applications in real life. Participation in the competition has been classified under four broad categories. Student can showcase their findings in various forms of expression like model, poster, soft presentation, animation, live performance, art and poetry. The basic focus of the competition is on using open source computation tools and modern technology, to emphasize the relationship of mathematical concepts with engineering applications in real life.

Global Power Play--Competition Winners Light Up the World

ERIC Educational Resources Information Center

Tech Directions, 2012

2012-01-01

This year's "Tech Directions" Inventors Competition asked students to come up with ways to provide electricity to remote villages that traditional electrical utilities have not yet reached. This article presents the results of the judging by inventor/electrical engineer Harry T. Roman. The winners are: (1) First Place--Scott Hulver,…

Championing the Value of Education: Why the Public Should Support the Schools.

ERIC Educational Resources Information Center

Funk, David L.

1991-01-01

Education is important because it directly affects our social quality of life, individual opportunities, national economic competitiveness, and other dimensions of life. Unfortunately, the true value of education is often only recognized by its absence. Although economic competitiveness is only one byproduct of national education quality, it does…

A Study of Factors Affecting University Professors' Research Output: Perspectives of Taiwanese Professors

ERIC Educational Resources Information Center

Yang, Jason Cheng-Cheng

2017-01-01

Higher education in Taiwan is facing competition and challenges from the macro environment of globalization. Taiwan's key policy direction is enhancing university quality in order to respond to these future trends. Universities' international competitiveness relies on not only faculty members' teaching quality, but also their research performance.…

76 FR 2168 - Self-Regulatory Organizations; EDGX Exchange, Inc.; Notice of Filing and Immediate Effectiveness...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-12

... proposed rule change reflects a competitive pricing structure designed to incent market participants to...) remains unchanged at $0.0032 per share. The Exchange believes that the above pricing is appropriate since... notes that it operates in a highly competitive market in which market participants can readily direct...

75 FR 71464 - Shorewood Packaging, a Subsidiary of International Paper Company, Including On-Site Leased...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-23

... published in the Federal Register on September 3, 2010 (75 FR 54187). The workers produce cigarette cartons... competitive with cigarette cartons; that neither the subject firm nor its major declining customers increased imports of articles like or directly competitive with cigarette cartons; that the subject workers are not...

The effect of environmental regulation on firms' competitive performance: the case of the building & construction sector in some EU regions.

PubMed

Testa, Francesco; Iraldo, Fabio; Frey, Marco

2011-09-01

There is a considerable debate on the effects of environmental regulation on competitive performance. Based on survey data, this paper analyzes the two main research questions, derived from literature, on the links between environmental regulation and competitiveness, by focusing on firms operating in the building and construction sector, i.e.: 1) whether environmental policy stringency affects the competitive performance of firms in the building and construction sector 2) and how a specific form of environmental regulation (direct regulation, economic instruments and soft instruments) affects this performance? By applying a regression analysis, we find that a more stringent environmental regulation, measured by inspection frequency, provides a positive impulse for increasing investments in advanced technological equipment and innovative products and on business performance. Moreover, a well-designed "direct regulation" appears to be the most effective policy instrument for prompting the positive impact of environmental policies on innovation and intangible performance while economic instruments do negatively affect business performance. Copyright © 2011 Elsevier Ltd. All rights reserved.

Frequency and direction of competitive anger in contact sports.

PubMed

Robazza, B; Bertollo, M; Bortoli, L

2006-09-01

The purpose of the present study was to investigate whether athletes involved in physical contact sports may interpret their feelings of anger as facilitative of performance, and to examine differences in the interpretation of anger as a function of the type of sport (team vs individual) or the competitive skill level (high vs low). A modified version of the State-Trait Anger Expression Inventory was administered to 100 Italian adult male athletes practicing rugby or individual combat sports (judo, freestyle wrestling, or Greco-Roman wrestling). The questionnaire was intended to measure the frequency and the direction (i.e., the facilitative-debilitative interpretation) of competitive anger. Many athletes engaged in contact sports tended interpret their competitive anger as facilitative of performance rather than debilitative. The type of sport and the athlete's standard level can mediate the individual's interpretation of the effects of anger symptoms upon performance. Competitors can interpret their anger as helpful to energize behavior and channel physical and mental resources for skill execution. Practitioners should assist athletes in gaining control over anger rather than attempting to suppress it.

Coping styles for trait shame and anxiety intensity and direction in competitive athletes.

PubMed

Partridge, Julie A; Wiggins, Matthew S

2008-12-01

The purpose of the study was to assess if athletes who perceived their anxiety as debilitative to performance also scored higher on ratings of coping styles used to handle trait shame. The sample was comprised of 94 participants (males = 44, females = 50) ranging in age from 15 to 24 years (M = 18.8, SD = 2.3). Athletes in high school (n = 21) and college (n = 73) representing several sports were surveyed for this study. Competitive sport experience averaged 11 yr. (SD = 3.9) overall. The Competitive Trait Anxiety Inventory-2D was given to collect general anxiety perceptions related to the athlete's specific sport. The Compass of Shame Scale-Sport was administered to measure coping styles for trait shame responses connected with competitive sport experiences. The athletes were divided into Facilitative (n = 39) and Debilitative anxiety groups (n = 55) based on the overall direction of anxiety scores. Multivariate analysis of variance indicated no interaction, but did reveal significant main effects for sex and anxiety group. Univariate tests indicated significant differences for several of the shame and anxiety subscales based on sex and anxiety group.

Geographic variation in apparent competition between native and invasive Phragmites australis.

PubMed

Bhattarai, Ganesh P; Meyerson, Laura A; Cronin, James T

2017-02-01

Apparent competition, the negative interaction between species mediated by shared natural enemies, is thought to play an important role in shaping the structure and dynamics of natural communities. However, its importance in driving species invasions, and whether the strength of this indirect interaction varies across the latitudinal range of the invasion, has not been fully explored. We performed replicated field experiments at four sites spanning 900 km along the Atlantic Coast of the United States to assess the presence and strength of apparent competition between sympatric native and invasive lineages of Phragmites australis. Four herbivore guilds were considered: stem-feeders, leaf-miners, leaf-chewers and aphids. We also tested the hypothesis that the strength of this interaction declines with increasing latitude. Within each site, native and invasive plants of P. australis were cross-transplanted between co-occurring native and invasive patches in the same marsh habitat and herbivore damage was evaluated at the end of the growing season. Apparent competition was evident for both lineages and involved all but the leaf-chewer guild. For native plants, total aphids per plant was 296% higher and the incidence of stem-feeding and leaf-mining herbivores was 34% and 221% higher, respectively, when transplanted into invasive than native patches. These data suggest that invasive P. australis has a negative effect on native P. australis via apparent competition. Averaged among herbivore types, the indirect effects of the invasive lineage on the native lineage was 57% higher than the reverse situation, suggesting that apparent competition was asymmetric. We also found that the strength of apparent competition acting against the native lineage was comparable to the benefits to the invasive lineage from enemy release (i.e., proportionately lower mean herbivory of the invasive relative to the native taxa). Finally, we found the first evidence that the strength of apparent competition acting against the native lineage (from stem-feeders only) decreased with increasing latitude. These results suggest that not only could apparent competition be of tantamount importance to enemy release in enhancing the establishment and spread of invasive taxa, but also that these indirect and direct herbivore effects could vary over the invasion range. © 2016 by the Ecological Society of America.

Competitor presence reduces internal attentional focus and improves 16.1km cycling time trial performance.

PubMed

Williams, Emily L; Jones, Hollie S; Andy Sparks, S; Marchant, David C; Midgley, Adrian W; Mc Naughton, Lars R

2015-07-01

Whilst the presence of a competitor has been found to improve performance, the mechanisms influencing the change in selected work rates during direct competition have been suggested but not specifically assessed. The aim was to investigate the physiological and psychological influences of a visual avatar competitor during a 16.1-km cycling time trial performance, using trained, competitive cyclists. Randomised cross-over design. Fifteen male cyclists completed four 16.1km cycling time trials on a cycle ergometer, performing two with a visual display of themselves as a simulated avatar (FAM and SELF), one with no visual display (DO), and one with themselves and an opponent as simulated avatars (COMP). Participants were informed the competitive avatar was a similar ability cyclist but it was actually a representation of their fastest previous performance. Increased performance times were evident during COMP (27.8±2.0min) compared to SELF (28.7±1.9min) and DO (28.4±2.3min). Greater power output, speed and heart rate were apparent during COMP trial than SELF (p<0.05) and DO (p≤0.06). There were no differences between SELF and DO. Ratings of perceived exertion were unchanged across all conditions. Internal attentional focus was significantly reduced during COMP trial (p<0.05), suggesting reduced focused on internal sensations during an increase in performance. Competitive cyclists performed significantly faster during a 16.1-km competitive trial than when performing maximally, without a competitor. The improvement in performance was elicited due to a greater external distraction, deterring perceived exertion. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

48 CFR 908.7101-3 - Direct acquisition.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Direct acquisition. 908.7101-3 Section 908.7101-3 Federal Acquisition Regulations System DEPARTMENT OF ENERGY COMPETITION ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Acquisition of Special Items 908.7101-3 Direct...

5 CFR 330.504 - Special restrictions after appointment under Part-time Direct Hire Program.

Code of Federal Regulations, 2010 CFR

2010-01-01

... under Part-time Direct Hire Program. 330.504 Section 330.504 Administrative Personnel OFFICE OF... To Protect Competitive Principles § 330.504 Special restrictions after appointment under Part-time Direct Hire Program. (a) A person hired under the Part-time Direct Hire Program may not be changed to...

Fully Connected Cascade Artificial Neural Network Architecture for Attention Deficit Hyperactivity Disorder Classification From Functional Magnetic Resonance Imaging Data.

PubMed

Deshpande, Gopikrishna; Wang, Peng; Rangaprakash, D; Wilamowski, Bogdan

2015-12-01

Automated recognition and classification of brain diseases are of tremendous value to society. Attention deficit hyperactivity disorder (ADHD) is a diverse spectrum disorder whose diagnosis is based on behavior and hence will benefit from classification utilizing objective neuroimaging measures. Toward this end, an international competition was conducted for classifying ADHD using functional magnetic resonance imaging data acquired from multiple sites worldwide. Here, we consider the data from this competition as an example to illustrate the utility of fully connected cascade (FCC) artificial neural network (ANN) architecture for performing classification. We employed various directional and nondirectional brain connectivity-based methods to extract discriminative features which gave better classification accuracy compared to raw data. Our accuracy for distinguishing ADHD from healthy subjects was close to 90% and between the ADHD subtypes was close to 95%. Further, we show that, if properly used, FCC ANN performs very well compared to other classifiers such as support vector machines in terms of accuracy, irrespective of the feature used. Finally, the most discriminative connectivity features provided insights about the pathophysiology of ADHD and showed reduced and altered connectivity involving the left orbitofrontal cortex and various cerebellar regions in ADHD.

The Competition Between a Localised and Distributed Source of Buoyancy

NASA Astrophysics Data System (ADS)

Partridge, Jamie; Linden, Paul

2012-11-01

We propose a new mathematical model to study the competition between localised and distributed sources of buoyancy within a naturally ventilated filling box. The main controlling parameters in this configuration are the buoyancy fluxes of the distributed and local source, specifically their ratio Ψ. The steady state dynamics of the flow are heavily dependent on this parameter. For large Ψ, where the distributed source dominates, we find the space becomes well mixed as expected if driven by an distributed source alone. Conversely, for small Ψ we find the space reaches a stable two layer stratification. This is analogous to the classical case of a purely local source but here the lower layer is buoyant compared to the ambient, due to the constant flux of buoyancy emanating from the distributed source. The ventilation flow rate, buoyancy of the layers and also the location of the interface height, which separates the two layer stratification, are obtainable from the model. To validate the theoretical model, small scale laboratory experiments were carried out. Water was used as the working medium with buoyancy being driven directly by temperature differences. Theoretical results were compared with experimental data and overall good agreement was found. A CASE award project with Arup.

Magneto immunosensor for gliadin detection in gluten-free foodstuff: towards food safety for celiac patients.

PubMed

Laube, T; Kergaravat, S V; Fabiano, S N; Hernández, S R; Alegret, S; Pividori, M I

2011-09-15

Gliadin is a constituent of the cereal protein gluten, responsible for the intolerance generated in celiac disease. Its detection is of high interest for food safety of celiac patients, since the only treatment known until now is a lifelong avoidance of this protein in the diet. Therefore, it is essential to have an easy and reliable method of analysis to control the contents in gluten-free foods. An electrochemical magneto immunosensor for the quantification of gliadin or small gliadin fragments in natural or pretreated food samples is described for the first time and compared to a novel magneto-ELISA system based on optical detection. The immunological reaction was performed on magnetic beads as solid support by the oriented covalent immobilization, of the protein gliadin on tosyl-activated beads. Direct, as well as indirect competitive immunoassays were optimized, achieving the best analytical performance with the direct competitive format. Excellent detection limits (in the order of μg L(-1)) were achieved, according to the legislation for gluten-free products. The matrix effect, as well as the performance of the assays was successfully evaluated using spiked gluten-free foodstuffs (skimmed milk and beer), obtaining excellent recovery values in the results. Copyright © 2011 Elsevier B.V. All rights reserved.

Are invasive plants more competitive than native conspecifics? Patterns vary with competitors

PubMed Central

Zheng, Yulong; Feng, Yulong; Valiente-Banuet, Alfonso; Li, Yangping; Liao, Zhiyong; Zhang, Jiaolin; Chen, Yajun

2015-01-01

Invasive plants are sometimes considered to be more competitive than their native conspecifics, according to the prediction that the invader reallocates resources from defense to growth due to liberation of natural enemies [‘Evolution of Increased Competitive Ability’ (EICA) hypothesis]. However, the differences in competitive ability may depend on the identity of competitors. In order to test the effects of competitors, Ageratina adenophora plants from both native and invasive ranges competed directly, and competed with native residents from both invasive (China) and native (Mexico) ranges respectively. Invasive A. adenophora plants were more competitive than their conspecifics from native populations when competing with natives from China (interspecific competition), but not when competing with natives from Mexico. Invasive A. adenophora plants also showed higher competitive ability when grown in high-density monoculture communities of plants from the same population (intrapopulation competition). In contrast, invasive A. adenophora plants showed lower competitive ability when competing with plants from native populations (intraspecific competition). Our results indicated that in the invasive range A. adenophora has evolved to effectively cope with co-occurring natives and high density environments, contributing to invasion success. Here, we showed the significant effects of competitors, which should be considered carefully when testing the EICA hypothesis. PMID:26489964

Ectomycorrhizal fungi and interspecific competition: species interactions, community structure, coexistence mechanisms, and future research directions.

PubMed

Kennedy, Peter

2010-09-01

The field of ectomycorrhizal fungal (EMF) ecology has largely developed outside the ecological mainstream, owing in large part to the challenges in studying the structure and dynamics of EMF communities. With advances in molecular identification and other research techniques, however, there has been growing interest among mycologists and ecologists in understanding how different ecological factors affect EMF community structure and diversity. While factors such as soil chemistry and host specificity have long been considered important, an increasing number of laboratory and field studies have documented that interspecific competition also has a major impact on EMF species interactions and may significantly influence EMF community structure. In this review, I examine the progress that has been made in understanding the nature of EMF competition. Currently, there are four conclusions that can be drawn: negative competitive effects are rarely reciprocal; competitive outcomes are environmentally context-dependent; field distributions often reflect competitive interactions; and timing of colonization influences competitive success. In addition, I highlight recent studies documenting links between competitive coexistence and EMF community structure, including checkerboard distributions, lottery models, storage effects, and colonization-competition tradeoffs. Finally, I discuss several aspects of EMF competition needing further investigation and some newer methods with which to address them.

Science vs. Sports: Motivation and Self-Concepts of Participants in Different School Competitions

ERIC Educational Resources Information Center

Höffler, Tim Niclas; Bonin, Victoria; Parchmann, Ilka

2017-01-01

Competitions are discussed as a measure to foster students' interest, especially for highly gifted and talented students. In the current study, participants of a cognitive school competition in science were compared to non-participants of the same age group (14-15) who either did not participate in any competition or who participated in a…

Root-shoot growth responses during interspecific competition quantified using allometric modelling.

PubMed

Robinson, David; Davidson, Hazel; Trinder, Clare; Brooker, Rob

2010-12-01

Plant competition studies are restricted by the difficulty of quantifying root systems of competitors. Analyses are usually limited to above-ground traits. Here, a new approach to address this issue is reported. Root system weights of competing plants can be estimated from: shoot weights of competitors; combined root weights of competitors; and slopes (scaling exponents, α) and intercepts (allometric coefficients, β) of ln-regressions of root weight on shoot weight of isolated plants. If competition induces no change in root : shoot growth, α and β values of competing and isolated plants will be equal. Measured combined root weight of competitors will equal that estimated allometrically from measured shoot weights of each competing plant. Combined root weights can be partitioned directly among competitors. If, as will be more usual, competition changes relative root and shoot growth, the competitors' combined root weight will not equal that estimated allometrically and cannot be partitioned directly. However, if the isolated-plant α and β values are adjusted until the estimated combined root weight of competitors matches the measured combined root weight, the latter can be partitioned among competitors using their new α and β values. The approach is illustrated using two herbaceous species, Dactylis glomerata and Plantago lanceolata. Allometric modelling revealed a large and continuous increase in the root : shoot ratio by Dactylis, but not Plantago, during competition. This was associated with a superior whole-plant dry weight increase in Dactylis, which was ultimately 2·5-fold greater than that of Plantago. Whole-plant growth dominance of Dactylis over Plantago, as deduced from allometric modelling, occurred 14-24 d earlier than suggested by shoot data alone. Given reasonable assumptions, allometric modelling can analyse competitive interactions in any species mixture, and overcomes a long-standing problem in studies of competition.

Hospital competition, resource allocation and quality of care

PubMed Central

Mukamel, Dana B; Zwanziger, Jack; Bamezai, Anil

2002-01-01

Background A variety of approaches have been used to contain escalating hospital costs. One approach is intensifying price competition. The increase in price based competition, which changes the incentives hospitals face, coupled with the fact that consumers can more easily evaluate the quality of hotel services compared with the quality of clinical care, may lead hospitals to allocate more resources into hotel rather than clinical services. Methods To test this hypothesis we studied hospitals in California in 1982 and 1989, comparing resource allocations prior to and following selective contracting, a period during which the focus of competition changed from quality to price. We estimated the relationship between clinical outcomes, measured as risk-adjusted-mortality rates, and resources. Results In 1989, higher competition was associated with lower clinical expenditures levels compared with 1982. The trend was stronger for non-profit hospitals. Lower clinical resource use was associated with worse risk adjusted mortality outcomes. Conclusions This study raises concerns that cost reductions may be associated with increased mortality. PMID:12052258

Modeling effects of intrinsic and extrinsic rewards on the competition between striatal learning systems

PubMed Central

Boedecker, Joschka; Lampe, Thomas; Riedmiller, Martin

2013-01-01

A common assumption in psychology, economics, and other fields holds that higher performance will result if extrinsic rewards (such as money) are offered as an incentive. While this principle seems to work well for tasks that require the execution of the same sequence of steps over and over, with little uncertainty about the process, in other cases, especially where creative problem solving is required due to the difficulty in finding the optimal sequence of actions, external rewards can actually be detrimental to task performance. Furthermore, they have the potential to undermine intrinsic motivation to do an otherwise interesting activity. In this work, we extend a computational model of the dorsomedial and dorsolateral striatal reinforcement learning systems to account for the effects of extrinsic and intrinsic rewards. The model assumes that the brain employs both a goal-directed and a habitual learning system, and competition between both is based on the trade-off between the cost of the reasoning process and value of information. The goal-directed system elicits internal rewards when its models of the environment improve, while the habitual system, being model-free, does not. Our results account for the phenomena that initial extrinsic reward leads to reduced activity after extinction compared to the case without any initial extrinsic rewards, and that performance in complex task settings drops when higher external rewards are promised. We also test the hypothesis that external rewards bias the competition in favor of the computationally efficient, but cruder and less flexible habitual system, which can negatively influence intrinsic motivation and task performance in the class of tasks we consider. PMID:24137146

The R292K Mutation That Confers Resistance to Neuraminidase Inhibitors Leads to Competitive Fitness Loss of A/Shanghai/1/2013 (H7N9) Influenza Virus in Ferrets

PubMed Central

Yen, Hui-Ling; Zhou, Jie; Choy, Ka-Tim; Sia, Sin Fun; Teng, Ooiean; Ng, Iris H.; Fang, Vicky J.; Hu, Yunwen; Wang, Wei; Cowling, Benjamin J.; Nicholls, John M.; Guan, Yi; Peiris, Joseph Sriyal Malik

2014-01-01

Background Neuraminidase (NA) inhibitors are the only licensed therapeutic option for human zoonotic H7N9 infections. An NA-R292K mutation that confers broad-spectrum resistance to NA inhibitors has been documented in H7N9 patients after treatment. Methods We evaluated the transmission potential of a human influenza A H7N9 isolate with a NA-R292K mutation in the ferret model followed by genotyping assay to monitor its competitive fitness in vivo. Results Plaque-purified A/Shanghai/1/2013 wild-type and NA-R292K viruses transmitted at comparable efficiency to direct or respiratory droplet contact ferrets. In ferrets inoculated with the plaque-purified A/Shanghai/1/2013 NA-R292K virus with dominant K292 (94%), the resistant K292 genotype was outgrown by the wild-type R292 genotype during the course of infection. Transmission of the resistant K292 genotype was detected in 3/4 direct contact and 3/4 respiratory droplet contact ferrets at early time points but was gradually replaced by the wild-type genotype. In the respiratory tissues of inoculated or infected ferrets, the wild-type R292 genotype dominated in the nasal turbinate, whereas the resistant K292 genotype was more frequently detected in the lungs. Conclusions The NA inhibitor-resistant H7N9 virus with the NA-R292K mutation may transmit among ferrets but showed compromised fitness in vivo while in competition with the wild-type virus. PMID:24951824

The R292K mutation that confers resistance to neuraminidase inhibitors leads to competitive fitness loss of A/Shanghai/1/2013 (H7N9) influenza virus in ferrets.

PubMed

Yen, Hui-Ling; Zhou, Jie; Choy, Ka-Tim; Sia, Sin Fun; Teng, Ooiean; Ng, Iris H; Fang, Vicky J; Hu, Yunwen; Wang, Wei; Cowling, Benjamin J; Nicholls, John M; Guan, Yi; Peiris, Joseph Sriyal Malik

2014-12-15

Neuraminidase (NA) inhibitors are the only licensed therapeutic option for human zoonotic H7N9 infections. An NA-R292K mutation that confers broad-spectrum resistance to NA inhibitors has been documented in H7N9 patients after treatment. We evaluated the transmission potential of a human influenza A H7N9 isolate with a NA-R292K mutation in the ferret model followed by genotyping assay to monitor its competitive fitness in vivo. Plaque-purified A/Shanghai/1/2013 wild-type and NA-R292K viruses transmitted at comparable efficiency to direct or respiratory droplet contact ferrets. In ferrets inoculated with the plaque-purified A/Shanghai/1/2013 NA-R292K virus with dominant K292 (94%), the resistant K292 genotype was outgrown by the wild-type R292 genotype during the course of infection. Transmission of the resistant K292 genotype was detected in 3/4 direct contact and 3/4 respiratory droplet contact ferrets at early time points but was gradually replaced by the wild-type genotype. In the respiratory tissues of inoculated or infected ferrets, the wild-type R292 genotype dominated in the nasal turbinate, whereas the resistant K292 genotype was more frequently detected in the lungs. The NA inhibitor-resistant H7N9 virus with the NA-R292K mutation may transmit among ferrets but showed compromised fitness in vivo while in competition with the wild-type virus. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Spatio-temporal Assessment Of The Land Use Implications Of Solar PV And Bioenergy Deployment In The UK TM Energy Model

NASA Astrophysics Data System (ADS)

Sobral Mourao, Z.; Konadu, D. D.; Skelton, S.; Lupton, R.

2015-12-01

The UK TIMES model (UKTM) succeeds the UK MARKAL as the underlying model of the UK Department of Energy and Climate Change (DECC) for long term energy system planning and policy development. It generates energy system pathways which achieve the 80% greenhouse gas (GHG) emissions reduction target by 2050, stipulated in the UK Climate Change Act (2008), at the least possible cost. Some of these pathways prescribe large-scale deployment of solar PV and indigenously sourced bioenergy, which are land intensive and could result in significant land use transitions; but would this create competition and stress for UK land use? To answer the above question, this study uses an integrated spatio-temporal modelling approach, ForeseerTM, which characterises the interdependencies between the energy and land systems by evaluating the land required under each pathways for solar PV and bioenergy, based on scenarios of a range of PV conversion efficiencies, and energy crop yield projections. The outcome is compared with availability of suitable locations for solar PV and sustainable limits of agricultural land appropriation for bioenergy production to assess potential stresses and competition with other land use services. Preliminary results show UKTM pathways could pose significant impact on the UK land use system. Bioenergy deployment could potentially compete with other land services by taking up a significant part of the available UK agricultural land thus competing directly with food production, most notably livestock production. For pathways with significant solar PV deployment, direct competition would not be focussed on the high quality land used for food crop production but rather for land used for livestock production and other ecosystem services.

19 CFR 210.50 - Commission action, the public interest, and bonding by respondents.

Code of Federal Regulations, 2011 CFR

2011-04-01

... section 337 of the Tariff Act of 1930 shall have upon the public health and welfare, competitive conditions in the U.S. economy, the production of like or directly competitive articles in the United States... administrative law judge's ability to take evidence or other information and to hear arguments from the parties...

These Kids Are Really on the Ball! Invention Competition Winners

ERIC Educational Resources Information Center

Tech Directions, 2008

2008-01-01

Judge Harry T. Roman, an electrical engineer and inventor himself, has selected the best entries in the 2007-2008 "Tech Directions" Inventors Award Competition. This year's challenge called for students to devise new uses for the common Ping-Pong ball. Of the results, the judge notes "The ideas submitted were most interesting, with a high number…

Speak Your Mind

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

Wiley, H. S.

2009-12-01

Good science comes from the open competition between ideas. Even the best hypotheses and conjectures are based on incomplete data and are influenced by inherent biases. Presenting these ideas in public provides an excellent opportunity to stack them up against the competition. I found that anticipation of a direct public question was also one of the most effective motivators for critical thinking.

76 FR 13246 - Self-Regulatory Organizations; EDGX Exchange, Inc.; Notice of Filing and Immediate Effectiveness...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-10

... infrastructure and administrative expenses. In addition, the rebate is competitive with rebates offered by Nasdaq... continue to offer a ``one under'' pricing model). The Exchange believes that adding an additional way to... competitive market in which market participants can readily direct order flow to competing venues if they deem...

Education and Signaling: Evidence from a Highly Competitive Labor Market

ERIC Educational Resources Information Center

Heywood, John S.; Wei, Xiangdong

2004-01-01

This paper directly tests for differences in returns to education between the employed and self-employed in Hong Kong. Using a step-function, we find significantly smaller returns for the self-employed, suggesting that in the highly competitive labor market of Hong Kong education plays a signaling role. This pattern persists for both genders, when…

Basic Psychological Skills Usage and Competitive Anxiety Responses: Perceived Underlying Mechanisms

ERIC Educational Resources Information Center

Wadey, Ross; Hanton, Sheldon

2008-01-01

This study examined the relationship between basic psychological skills usage (i.e., goal-setting, imagery, self-talk, and relaxation) and the intensity and directional dimensions of competitive anxiety. Semistructured interviews were used on a sample of 15 elite athletes (M age = 24.3 years, SD = 4.2) from a variety of team and individual sports.…

Securing an OTL-HNS residency: how competitive is it? Comparing medical student perceptions to actual Canadian statistics.

PubMed

Kay-Rivest, E; Varma, N; Scott, G M; Manoukian, J J; Desrosiers, M; Vaccani, J P; Nguyen, L H P

2017-02-27

The residency match is an important event in an aspiring physician's career. Otolaryngology - Head and Neck Surgery (OTL-HNS) is a surgical specialty that has enjoyed high numbers of applicants to its residency programs. However, recent trends in Canada show a decline in first-choice applicants to several surgical fields. Factors thought to influence a medical student's choice include role models, career opportunities and work-life balance. The notion of perceived competitiveness is a factor that has not yet been explored. This study sought to compare competitiveness of OTL-HNS, as perceived by Canadian medical students to residency match statistics published yearly by CaRMS (Canadian Residency Matching Service), with the hope of informing future decisions of surgical residency programs. An electronic survey was created and distributed to all medical students enrolled in the 17 Canadian medical schools. After gathering demographic information, students were asked to rank what they perceived to be the five most competitive disciplines offered by CaRMS. They were also asked to rank surgical specialties from most to least competitive. Publically available data from CaRMS was then collected and analyzed to determine actual competitiveness of admissions to Canadian OTL-HNS residency programs. 1194 students, from first to fourth year of medical school, completed the survey. CaRMS statistics over the period from 2008 to 2014 demonstrated that the five most competitive specialties were Plastic Surgery, Dermatology, Ophthalmology, Emergency Medicine and OTL-HNS. Among surgical disciplines, OTL-HNS was third most competitive, where on average 72% of students match to their first-choice discipline. When students were questioned, 35% ranked OTL-HNS amongst the top five most competitive. On the other hand 72%, 74% and 80% recognized Opthalmology, Dermatology and Plastic Surgery as being among the five most competitive, respectively. We found that fourth-year medical students were significantly more knowledgeable about the competitiveness of both OTL-HNS and Plastic Surgery compared to first-year students (p < 0.01). Overall, Canadian medical students may underestimate the competitiveness of OTL-HNS. Furthermore, competitiveness would appear to be a concept that resonates with medical students during the match process.

Revisiting the U.S.-Soviet space race: Comparing two systems in their competition to land a man on the moon

NASA Astrophysics Data System (ADS)

Erickson, Andrew S.

2018-07-01

The Cold War space competition between the U.S. and the USSR, centered on their race to the moon, offers both an important historical case and larger implications for space and technology development and policy. In the late 1950s, under Premier Nikita Khrushchev's direction and Chief Designer Sergei Korolev's determined implementation, Moscow's capabilities appeared to eclipse Washington's. This called the international system's very nature into question and prompted President John F. Kennedy to declare a race to the moon. Despite impressive goals and talented engineers, in the centralized but under-institutionalized, resource-limited Soviet Union feuding chief designers playing bureaucratic politics promoted a cacophony of overambitious, overlapping, often uncompleted projects. The USSR suffered from inadequate standardization and quality control at outlying factories and failed to sustain its lead. In marked contrast, American private corporations, under NASA's well-coordinated guidance and adjudication, helped the United States overtake from behind to meet Kennedy's deadline in 1969. In critical respects, Washington's lunar landing stemmed from an effective systems management program, while Moscow's moonshot succumbed to the Soviet system, which proved unequal to the task. In less than a decade, Soviet space efforts shifted from one-upping, to keeping up, to covering up. This article reconsiders this historic competition and suggests larger conclusions.

Study of major factors developed among young swimmers during the practice session and competition causing interference of their performances.

PubMed

Das, Pradip Kumar; Panja, Debjit

2013-12-01

Swimming is a mass-oriented, well organised and health directed sport which helps to acquire good health for the participants. In our country it is started mostly in the 8-9 years of age and when compared to developed countries the children start the practices around the 3-6 years of age. In swimming like other sports, injury can happen particularly during practice and events competition. The different types of injuries like shoulder joint injury, knee joint injury, red eyes, ear-nose infections, muscle cramps, etc, so happened during swimming practice and swimming competition, affect the performances of the swimmers on many different levels, in both training and in swim meets. This is an ongoing problem for many swimmers, moreover swimming is an intense workout, so it's important to make sure for getting adequate nutrition throughout the day. Proper nutrition and dieting play a large role in optimising swimming performance. A poor diet has a negative effect on athletic performance, as it is also evident in this study where most of the swimmers are suffering from nutritional anaemia as detected by the low level of haemoglobin in their blood and so today the study work has obviously thrown some light on this aspect to highlight the problems and their solutions.

Preprocessing and meta-classification for brain-computer interfaces.

PubMed

Hammon, Paul S; de Sa, Virginia R

2007-03-01

A brain-computer interface (BCI) is a system which allows direct translation of brain states into actions, bypassing the usual muscular pathways. A BCI system works by extracting user brain signals, applying machine learning algorithms to classify the user's brain state, and performing a computer-controlled action. Our goal is to improve brain state classification. Perhaps the most obvious way to improve classification performance is the selection of an advanced learning algorithm. However, it is now well known in the BCI community that careful selection of preprocessing steps is crucial to the success of any classification scheme. Furthermore, recent work indicates that combining the output of multiple classifiers (meta-classification) leads to improved classification rates relative to single classifiers (Dornhege et al., 2004). In this paper, we develop an automated approach which systematically analyzes the relative contributions of different preprocessing and meta-classification approaches. We apply this procedure to three data sets drawn from BCI Competition 2003 (Blankertz et al., 2004) and BCI Competition III (Blankertz et al., 2006), each of which exhibit very different characteristics. Our final classification results compare favorably with those from past BCI competitions. Additionally, we analyze the relative contributions of individual preprocessing and meta-classification choices and discuss which types of BCI data benefit most from specific algorithms.

Small-scale grassland assembly patterns differ above and below the soil surface.

PubMed

Price, Jodi N; Hiiesalu, Inga; Gerhold, Pille; Pärtel, Meelis

2012-06-01

The existence of deterministic assembly rules for plant communities remains an important and unresolved topic in ecology. Most studies examining community assembly have sampled aboveground species diversity and composition. However, plants also coexist belowground, and many coexistence theories invoke belowground competition as an explanation for aboveground patterns. We used next-generation sequencing that enables the identification of roots and rhizomes from mixed-species samples to measure coexisting species at small scales in temperate grasslands. We used comparable data from above (conventional methods) and below (molecular techniques) the soil surface (0.1 x 0.1 x 0.1 m volume). To detect evidence for nonrandom patterns in the direction of biotic or abiotic assembly processes, we used three assembly rules tests (richness variance, guild proportionality, and species co-occurrence indices) as well as pairwise association tests. We found support for biotic assembly rules aboveground, with lower variance in species richness than expected and more negative species associations. Belowground plant communities were structured more by abiotic processes, with greater variability in richness and guild proportionality than expected. Belowground assembly is largely driven by abiotic processes, with little evidence for competition-driven assembly, and this has implications for plant coexistence theories that are based on competition for soil resources.

The Dilemma of Competition Encountered by Musically Gifted Asian Male Students: An Exploration from the Perspective of Gifted Education

ERIC Educational Resources Information Center

Kao, Chen-Yao

2011-01-01

Due to the crucial role of competition in advanced performance, musically gifted students are more likely to experience competitive conditions compared with students in regular classes. However, there is a surprising paucity of research on the relationships between competition and musical giftedness. Through a research design of a qualitative…

Comparative virulence and competition between Nosema apis and Nosema ceranae in honey bees (Apis mellifera).

PubMed

Milbrath, Meghan O; van Tran, Toan; Huang, Wei-Fong; Solter, Leellen F; Tarpy, David R; Lawrence, Frank; Huang, Zachary Y

2015-02-01

Honey bees (Apis mellifera) are infected by two species of microsporidia: Nosema apis and Nosemaceranae. Epidemiological evidence indicates that N. ceranae may be replacing N. apis globally in A. mellifera populations, suggesting a potential competitive advantage of N. ceranae. Mixed infections of the two species occur, and little is known about the interactions among the host and the two pathogens that have allowed N. ceranae to become dominant in most geographical areas. We demonstrated that mixed Nosema species infections negatively affected honey bee survival (median survival=15-17days) more than single species infections (median survival=21days and 20days for N. apis and N. ceranae, respectively), with median survival of control bees of 27days. We found similar rates of infection (percentage of bees with active infections after inoculation) for both species in mixed infections, with N. apis having a slightly higher rate (91% compared to 86% for N. ceranae). We observed slightly higher spore counts in bees infected with N. ceranae than in bees infected with N. apis in single microsporidia infections, especially at the midpoint of infection (day 10). Bees with mixed infections of both species had higher spore counts than bees with single infections, but spore counts in mixed infections were highly variable. We did not see a competitive advantage for N. ceranae in mixed infections; N. apis spore counts were either higher or counts were similar for both species and more N. apis spores were produced in 62% of bees inoculated with equal dosages of the two microsporidian species. N. ceranae does not, therefore, appear to have a strong within-host advantage for either infectivity or spore growth, suggesting that direct competition in these worker bee mid-guts is not responsible for its apparent replacement of N. apis. Copyright © 2014 Elsevier Inc. All rights reserved.

Comparison of three approaches to model grapevine organogenesis in conditions of fluctuating temperature, solar radiation and soil water content.

PubMed

Pallas, B; Loi, C; Christophe, A; Cournède, P H; Lecoeur, J

2011-04-01

There is increasing interest in the development of plant growth models representing the complex system of interactions between the different determinants of plant development. These approaches are particularly relevant for grapevine organogenesis, which is a highly plastic process dependent on temperature, solar radiation, soil water deficit and trophic competition. The extent to which three plant growth models were able to deal with the observed plasticity of axis organogenesis was assessed. In the first model, axis organogenesis was dependent solely on temperature, through thermal time. In the second model, axis organogenesis was modelled through functional relationships linking meristem activity and trophic competition. In the last model, the rate of phytomer appearence on each axis was modelled as a function of both the trophic status of the plant and the direct effect of soil water content on potential meristem activity. The model including relationships between trophic competition and meristem behaviour involved a decrease in the root mean squared error (RMSE) for the simulations of organogenesis by a factor nine compared with the thermal time-based model. Compared with the model in which axis organogenesis was driven only by trophic competition, the implementation of relationships between water deficit and meristem behaviour improved organogenesis simulation results, resulting in a three times divided RMSE. The resulting model can be seen as a first attempt to build a comprehensive complete plant growth model simulating the development of the whole plant in fluctuating conditions of temperature, solar radiation and soil water content. We propose a new hypothesis concerning the effects of the different determinants of axis organogenesis. The rate of phytomer appearance according to thermal time was strongly affected by the plant trophic status and soil water deficit. Furthermore, the decrease in meristem activity when soil water is depleted does not result from source/sink imbalances.

Comparison of nested competitive RT-PCR and real-time RT-PCR for the detection and quantification of AML1/MTG8 fusion transcripts in t(8;21) positive acute myelogenous leukemia.

PubMed

Wattjes, M P; Krauter, J; Nagel, S; Heidenreich, O; Ganser, A; Heil, G

2000-02-01

The chromosomal translocation t(8;21)(q22;q22) is one of the most frequent karyotypic aberrations in acute myeloid leukemia (AML) and results in a chimeric fusion transcript AML1/MTG8. Since AML1/MTG8 fusion transcripts remain detectable by RT-PCR in t(8;21) AML patients in long-term hematological remission, quantitative assessment of AML1/MTG8 transcripts is necessary for the monitoring of minimal residual disease (MRD) in these patients. Competitive RT-PCR and recently real-time RT-PCR are increasingly used for detection and quantification of leukemia specific fusion transcripts. For the direct comparison of both methods we cloned a 42 bp DNA fragment into the original AML1/MTG8 sequence. The resulting molecule was used as an internal competitor for our novel competitive nested RT-PCR for AML1/MTG8 and as an external standard for the generation of AML1/MTG8 standard curves in a real-time PCR assay. Using this standard molecule for both PCR techniques, we compared their sensitivity, linearity and reproducibility. Both methods were comparable with regard to all parameters tested irrespective of analyzing serial dilutions of plasmids, cell lines or samples from t(8;21) positive AML patients at different stages of the disease. Therefore, both techniques can be recommended for the monitoring of MRD in these particular AML patients. However, the automatization of the real-time PCR technique offers some technical advantages.

Shape reanalysis and sensitivities utilizing preconditioned iterative boundary solvers

NASA Technical Reports Server (NTRS)

Guru Prasad, K.; Kane, J. H.

1992-01-01

The computational advantages associated with the utilization of preconditined iterative equation solvers are quantified for the reanalysis of perturbed shapes using continuum structural boundary element analysis (BEA). Both single- and multi-zone three-dimensional problems are examined. Significant reductions in computer time are obtained by making use of previously computed solution vectors and preconditioners in subsequent analyses. The effectiveness of this technique is demonstrated for the computation of shape response sensitivities required in shape optimization. Computer times and accuracies achieved using the preconditioned iterative solvers are compared with those obtained via direct solvers and implicit differentiation of the boundary integral equations. It is concluded that this approach employing preconditioned iterative equation solvers in reanalysis and sensitivity analysis can be competitive with if not superior to those involving direct solvers.

Competition for hydrogen-bond formation in the helix-coil transition and protein folding

NASA Astrophysics Data System (ADS)

Badasyan, A. V.; Tonoyan, Sh. A.; Mamasakhlisov, Y. Sh.; Giacometti, Achille; Benight, A. S.; Morozov, V. F.

2011-05-01

The problem of the helix-coil transition of biopolymers in explicit solvents, such as water, with the ability for hydrogen bonding with a solvent is addressed analytically using a suitably modified version of the Generalized Model of Polypeptide Chains. Besides the regular helix-coil transition, an additional coil-helix or reentrant transition is also found at lower temperatures. The reentrant transition arises due to competition between polymer-polymer and polymer-water hydrogen bonds. The balance between the two types of hydrogen bonding can be shifted to either direction through changes not only in temperature, but also by pressure, mechanical force, osmotic stress, or other external influences. Both polypeptides and polynucleotides are considered within a unified formalism. Our approach provides an explanation of the experimental difficulty of observing the reentrant transition with pressure and underscores the advantage of pulling experiments for studies of DNA. Results are discussed and compared with those reported in a number of recent publications with which a significant level of agreement is obtained.

Small Stirling dynamic isotope power system for multihundred-watt robotic missions

NASA Technical Reports Server (NTRS)

Bents, David J.

1991-01-01

Free Piston Stirling Engine (FPSE) and linear alternator (LA) technology is combined with radioisotope heat sources to produce a compact dynamic isotope power system (DIPS) suitable for multihundred watt space application which appears competitive with advance radioisotope thermoelectric generators (RTGs). The small Stirling DIPS is scalable to multihundred watt power levels or lower. The FPSE/LA is a high efficiency convertor in sizes ranging from tens of kilowatts down to only a few watts. At multihundred watt unit size, the FPSE can be directly integrated with the General Purpose Heat Source (GPHS) via radiative coupling; the resulting dynamic isotope power system has a size and weight that compares favorably with the advanced modular (Mod) RTG, but requires less than a third the amount of isotope fuel. Thus the FPSE extends the high efficiency advantage of dynamic systems into a power range never previously considered competitive for DIPS. This results in lower fuel cost and reduced radiological hazard per delivered electrical watt.

Small Stirling dynamic isotope power system for multihundred-watt robotic missions

NASA Technical Reports Server (NTRS)

Bents, David J.

1991-01-01

Free piston Stirling Engine (FPSE) and linear alternator (LA) technology is combined with radioisotope heat sources to produce a compact dynamic isotope power system (DIPS) suitable for multihundred watt space application which appears competitive with advanced radioisotope thermoelectric generators (RTGs). The small Stirling DIPS is scalable to multihundred watt power levels or lower. The FPSE/LA is a high efficiency convertor in sizes ranging from tens of kilowatts down to only a few watts. At multihundred watt unit size, the FPSE can be directly integrated with the General Purpose Heat Source (GPHS) via radiative coupling; the resulting dynamic isotope power system has a size and weight that compares favorably with the advanced modular (Mod) RTG, but requires less than a third the amount of isotope fuel. Thus the FPSE extends the high efficiency advantage of dynamic systems into a power range never previously considered competitive for DIPS. This results in lower fuel cost and reduced radiological hazard per delivered electrical watt.

78 FR 31593 - Notice of Determinations Regarding Eligibility to Apply for Worker Adjustment Assistance

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-24

..., as amended (19 U.S.C. 2273) the Department of Labor herein presents summaries of determinations... produced by such firm are directly incorporated, have increased; (C) imports of articles directly... firm have increased; (D) imports of articles like or directly competitive with articles which are...

Two opposite dose-dependent effects of diazinon on the motor activity of the rat ileum.

PubMed

Trailović, Saša M; Marjanović, Djordje S; Uzelac, Teodora Vidonja; Milovanović, Mirjana; Trailović, Jelena Nedeljković

2017-06-01

Acute poisoning with OPs may lead to a range of neurological effects, which cannot be explained by AChE inhibition alone. Several OPs interact directly with cholinergic receptors in mammals, but such data does not exist for invertebrates. The aim of current study was to investigate the direct and indirect effects of diazinon on the contractions of rat ileum and to compare those effects on the nervemuscle preparation of the Ascaris suum. In the presence of increasing concentrations of diazinon (3, 10 and 30nM), EFS-induced ileal contractions were increased significantly. In the same preparation, diazinon 3nM, significantly increased contractions induced by EFS, but did not affect the contractions caused by 5MFI. Contrarily, 1μM of diazinon significantly and reversibly inhibited the EFS-induced ileal contractions. Diazinon exhibited competitive and non-competitive inhibitions of 5MFI induced contractions. The control EC 50 of 5MFI was 2.48μM with R max =1.88g. In the presence of diazinon, EC 50 was 12.45μM, while R max was reduced to 0.43g. After washing, the EC 50 and R max values were again closer to the control level (3.80μM and 1.04g). Diazinon 1μM did not inhibit Ascaris suum contractions caused by ACh, but it increased the R max . Diazinon in our study exhibits two opposite effects on the motor activity of the ileum. In low nanomolar concentrations the dominat is its effect on AChE and the stimulation of contractions. Furthermore, in concentrations that approach micromolar values diazinon has a direct inhibitory effect on muscarinic receptors. The direct inhibitory effect of diazinon on A. suum contractions was not found. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluating structural pattern recognition for handwritten math via primitive label graphs

NASA Astrophysics Data System (ADS)

Zanibbi, Richard; Mouchère, Harold; Viard-Gaudin, Christian

2013-01-01

Currently, structural pattern recognizer evaluations compare graphs of detected structure to target structures (i.e. ground truth) using recognition rates, recall and precision for object segmentation, classification and relationships. In document recognition, these target objects (e.g. symbols) are frequently comprised of multiple primitives (e.g. connected components, or strokes for online handwritten data), but current metrics do not characterize errors at the primitive level, from which object-level structure is obtained. Primitive label graphs are directed graphs defined over primitives and primitive pairs. We define new metrics obtained by Hamming distances over label graphs, which allow classification, segmentation and parsing errors to be characterized separately, or using a single measure. Recall and precision for detected objects may also be computed directly from label graphs. We illustrate the new metrics by comparing a new primitive-level evaluation to the symbol-level evaluation performed for the CROHME 2012 handwritten math recognition competition. A Python-based set of utilities for evaluating, visualizing and translating label graphs is publicly available.

Virulence and competitive ability in genetically diverse malaria infections

PubMed Central

de Roode, Jacobus C.; Pansini, Riccardo; Cheesman, Sandra J.; Helinski, Michelle E. H.; Huijben, Silvie; Wargo, Andrew R.; Bell, Andrew S.; Chan, Brian H. K.; Walliker, David; Read, Andrew F.

2005-01-01

Explaining parasite virulence is a great challenge for evolutionary biology. Intuitively, parasites that depend on their hosts for their survival should be benign to their hosts, yet many parasites cause harm. One explanation for this is that within-host competition favors virulence, with more virulent strains having a competitive advantage in genetically diverse infections. This idea, which is well supported in theory, remains untested empirically. Here we provide evidence that within-host competition does indeed select for high parasite virulence. We examine the rodent malaria Plasmodium chabaudi in laboratory mice, a parasite–host system in which virulence can be easily monitored and competing strains quantified by using strain-specific real-time PCR. As predicted, we found a strong relationship between parasite virulence and competitive ability, so that more virulent strains have a competitive advantage in mixed-strain infections. In transmission experiments, we found that the strain composition of the parasite populations in mosquitoes was directly correlated with the composition of the blood-stage parasite population. Thus, the outcome of within-host competition determined relative transmission success. Our results imply that within-host competition is a major factor driving the evolution of virulence and can explain why many parasites harm their hosts. PMID:15894623

Analysis of inter-country input-output table based on citation network: How to measure the competition and collaboration between industrial sectors on the global value chain

PubMed Central

2017-01-01

The input-output table is comprehensive and detailed in describing the national economic system with complex economic relationships, which embodies information of supply and demand among industrial sectors. This paper aims to scale the degree of competition/collaboration on the global value chain from the perspective of econophysics. Global Industrial Strongest Relevant Network models were established by extracting the strongest and most immediate industrial relevance in the global economic system with inter-country input-output tables and then transformed into Global Industrial Resource Competition Network/Global Industrial Production Collaboration Network models embodying the competitive/collaborative relationships based on bibliographic coupling/co-citation approach. Three indicators well suited for these two kinds of weighted and non-directed networks with self-loops were introduced, including unit weight for competitive/collaborative power, disparity in the weight for competitive/collaborative amplitude and weighted clustering coefficient for competitive/collaborative intensity. Finally, these models and indicators were further applied to empirically analyze the function of sectors in the latest World Input-Output Database, to reveal inter-sector competitive/collaborative status during the economic globalization. PMID:28873432

A Cascade of Champions: A Qualitative Study about the MA-CORD Media Competition Implementation

PubMed Central

Criss, Shaniece; Tran, Alvin; Ganter, Claudia; Aftosmes-Tobio, Alyssa; Gortmaker, Steven; Viswanath, Kasisomayajula; Kwass, Jo-Ann; Davison, Kirsten K.

2016-01-01

A media competition was part of the Massachusetts Childhood Obesity Research Demonstration (MA-CORD) Study. Criss et al., previously outlined the development and implementation of the competition, including variation in reach and adoption of the intervention across schools and afterschool programs. In this qualitative study, we examine community, provider, and organizational factors that explain the variation of media competition reach in school and afterschool programs, and describe the awareness of the media competition across other community sectors. Durlak and DuPre’s ecological framework for understanding effective implementation provided the theoretical underpinnings for this study. Fifty-four key informant interviews were conducted, transcribed, and analyzed. Organizational capacity of committed teachers/staff and adaptability of the media competition seemed to be drivers for higher reach within school and afterschool programs. Salient themes that emerged as facilitators of effective implementation were having a cascade of champions and providing opportunity to participate in the media competition outside traditional class time. Clinics and coalitions were identified as additional sectors aware of the media competition. Specifically, our findings offer a new perspective on intervention design and a recommended direction for further study. PMID:27058550

Analysis of inter-country input-output table based on citation network: How to measure the competition and collaboration between industrial sectors on the global value chain.

PubMed

Xing, Lizhi

2017-01-01

The input-output table is comprehensive and detailed in describing the national economic system with complex economic relationships, which embodies information of supply and demand among industrial sectors. This paper aims to scale the degree of competition/collaboration on the global value chain from the perspective of econophysics. Global Industrial Strongest Relevant Network models were established by extracting the strongest and most immediate industrial relevance in the global economic system with inter-country input-output tables and then transformed into Global Industrial Resource Competition Network/Global Industrial Production Collaboration Network models embodying the competitive/collaborative relationships based on bibliographic coupling/co-citation approach. Three indicators well suited for these two kinds of weighted and non-directed networks with self-loops were introduced, including unit weight for competitive/collaborative power, disparity in the weight for competitive/collaborative amplitude and weighted clustering coefficient for competitive/collaborative intensity. Finally, these models and indicators were further applied to empirically analyze the function of sectors in the latest World Input-Output Database, to reveal inter-sector competitive/collaborative status during the economic globalization.

Refuge-mediated apparent competition in plant-consumer interactions.

PubMed

Orrock, John L; Holt, Robert D; Baskett, Marissa L

2010-01-01

At the intersection of consumer behaviour and plant competition is the concept of refuge-mediated apparent competition: an indirect interaction whereby plants provide a refuge for a shared consumer, subsequently increasing consumer pressure on another plant species. Here, we use a simple model and empirical examples to develop and illustrate the concept of refuge-mediated apparent competition. We find that the likelihood that an inferior competitor will succeed via refuge-mediated apparent competition is greater when competitors have similar resource requirements and when consumers exhibit a strong response to the refuge and high attack rates on the superior competitor. Refuge-mediated apparent competition may create an emergent Allee effect, such that a species invades only if it is sufficiently abundant to alter consumer impact on resident species. This indirect interaction may help explain unresolved patterns observed in biological invasion, such as the different physical structure of invasive exotic plants, the lag phase, and the failure of restoration efforts. Given the ubiquity of refuge-seeking behaviour by consumers and the ability of consumers to alter the outcome of direct competition among plants, refuge-mediated apparent competition may be an underappreciated mechanism affecting the composition and diversity of plant communities.

A Relational Approach to Measuring Competition Among Hospitals

PubMed Central

Sohn, Min-Woong

2002-01-01

Objective To present a new, relational approach to measuring competition in hospital markets and to compare this relational approach with alternative methods of measuring competition. Data Sources The California Office of Statewide Health Planning and Development patient discharge abstracts and financial disclosure files for 1991. Study Design Patient discharge abstracts for an entire year were used to derive patient flows, which were combined to calculate the extent of overlap in patient pools for each pair of hospitals. This produces a cross-sectional measure of market competition among hospitals. Principal Findings The relational approach produces measures of competition between each and every pair of hospitals in the study sample, allowing us to examine a much more “local” as well as dyadic effect of competition. Preliminary analyses show the following: (1) Hospital markets are smaller than thought. (2) For-profit hospitals received considerably more competition from their neighbors than either nonprofit or government hospitals. (3) The size of a hospital does not matter in the amount of competition received, but the larger hospitals generated significantly more competition than smaller ones. Comparisons of this method to the other methods show considerable differences in identifying competitors, indicating that these methods are not as comparable as previously thought. Conclusion The relational approach measures competition in a more detailed way and allows researchers to conduct more fine-grained analyses of market competition. This approach allows one to model market structure in a manner that goes far beyond the traditional categories of monopoly, oligopoly, and perfect competition. It also opens up an entirely new range of analytic possibilities in examining the effect of competition on hospital performance, price of medical care, changes in the market, technology acquisition, and many other phenomena in the health care field. PMID:12036003

Direction of interaction between mountain pine beetle (Dendroctonus ponderosae) and resource-sharing wood-boring beetles depends on plant parasite infection.

PubMed

Klutsch, Jennifer G; Najar, Ahmed; Cale, Jonathan A; Erbilgin, Nadir

2016-09-01

Plant pathogens can have cascading consequences on insect herbivores, though whether they alter competition among resource-sharing insect herbivores is unknown. We experimentally tested whether the infection of a plant pathogen, the parasitic plant dwarf mistletoe (Arceuthobium americanum), on jack pine (Pinus banksiana) altered the competitive interactions among two groups of beetles sharing the same resources: wood-boring beetles (Coleoptera: Cerambycidae) and the invasive mountain pine beetle (Dendroctonus ponderosae) (Coleoptera: Curculionidae). We were particularly interested in identifying potential mechanisms governing the direction of interactions (from competition to facilitation) between the two beetle groups. At the lowest and highest disease severity, wood-boring beetles increased their consumption rate relative to feeding levels at moderate severity. The performance (brood production and feeding) of mountain pine beetle was negatively associated with wood-boring beetle feeding and disease severity when they were reared separately. However, when both wood-boring beetles and high severity of plant pathogen infection occurred together, mountain pine beetle escaped from competition and improved its performance (increased brood production and feeding). Species-specific responses to changes in tree defense compounds and quality of resources (available phloem) were likely mechanisms driving this change of interactions between the two beetle groups. This is the first study demonstrating that a parasitic plant can be an important force in mediating competition among resource-sharing subcortical insect herbivores.

Monitoring of immunological parameters in adolescent basketball athletes during and after a sports season.

PubMed

Brunelli, Diego Trevisan; Rodrigues, Ariel; Lopes, Wendell Arthur; Gáspari, Arthur Fernandes; Bonganha, Valéria; Montagner, Paulo César; Borin, João Paulo; Cavaglieri, Cláudia Regina

2014-01-01

The objective of the present study was to monitor the immunological and hormonal responses and the occurrence of upper respiratory symptoms in adolescent basketball athletes during the different stages of a sports season. Anthropometric measures, biochemical analyses (interleukin-6, interleukin-10, tumour necrosis factor-alpha, C-reactive protein, testosterone and cortisol), neuromuscular evaluations (standing vertical jumping ability, agility and estimated VO2max) and leukocyte counts were performed at four moments: 72 h before the season (-72 h); before the season (Pre-season); after six weeks, at the end of the preparatory period (Preparatory); and after 20 weeks, at the end of the competitive period (Competitive). Also, the occurrence of upper respiratory symptoms was collected weekly during all stages of the season. There were significant increases in monocytes, cortisol, tumour necrosis factor-alpha and C-reactive protein at the Competitive moment as compared to the Pre-season. In addition, interleukin-10 decreased at the Competitive moment as compared to the Pre-season. Occurrence of upper respiratory symptoms demonstrated increases (38%) during the competitive period as compared to the preparatory. These results suggest that periods of training and competition could increase the occurrence of upper respiratory symptoms in adolescent athletes and this may be due to the unwanted effects of an inflammatory process in response to the excessive stress of training and competition.

Competition for space during bacterial colonization of a surface.

PubMed

Lloyd, Diarmuid P; Allen, Rosalind J

2015-09-06

Competition for space is ubiquitous in the ecology of both microorganisms and macro-organisms. We introduce a bacterial model system in which the factors influencing competition for space during colonization of an initially empty habitat can be tracked directly. Using fluorescence microscopy, we follow the fate of individual Escherichia coli bacterial cell lineages as they undergo expansion competition (the race to be the first to colonize a previously empty territory), and as they later compete at boundaries between clonal territories. Our experiments are complemented by computer simulations of a lattice-based model. We find that both expansion competition, manifested as differences in individual cell lag times, and boundary competition, manifested as effects of neighbour cell geometry, can play a role in colonization success, particularly when lineages expand exponentially. This work provides a baseline for investigating how ecological interactions affect colonization of space by bacterial populations, and highlights the potential of bacterial model systems for the testing and development of ecological theory. © 2015 The Authors.

Competition for space during bacterial colonization of a surface

PubMed Central

Lloyd, Diarmuid P.; Allen, Rosalind J.

2015-01-01

Competition for space is ubiquitous in the ecology of both microorganisms and macro-organisms. We introduce a bacterial model system in which the factors influencing competition for space during colonization of an initially empty habitat can be tracked directly. Using fluorescence microscopy, we follow the fate of individual Escherichia coli bacterial cell lineages as they undergo expansion competition (the race to be the first to colonize a previously empty territory), and as they later compete at boundaries between clonal territories. Our experiments are complemented by computer simulations of a lattice-based model. We find that both expansion competition, manifested as differences in individual cell lag times, and boundary competition, manifested as effects of neighbour cell geometry, can play a role in colonization success, particularly when lineages expand exponentially. This work provides a baseline for investigating how ecological interactions affect colonization of space by bacterial populations, and highlights the potential of bacterial model systems for the testing and development of ecological theory. PMID:26333814

Competitive displacement among post-Paleozoic cyclostome and cheilostome bryozoans

NASA Technical Reports Server (NTRS)

Sepkoski, J. J. Jr; McKinney, F. K.; Lidgard, S.; Sepkoski JJ, J. r. (Principal Investigator)

2000-01-01

Encrusting bryozoans provide one of the few systems in the fossil record in which ecological competition can be observed directly at local scales. The macroevolutionary history of diversity of cyclostome and cheilostome bryozoans is consistent with a coupled-logistic model of clade displacement predicated on species within clades interacting competitively. The model matches observed diversity history if the model is perturbed by a mass extinction with a position and magnitude analogous to the Cretaceous/Tertiary boundary event, Although it is difficult to measure all parameters in the model from fossil data, critical factors are intrinsic rates of extinction, which can be measured. Cyclostomes maintained a rather low rate of extinction, and the model solutions predict that they would lose diversity only slowly as competitively superior species of cheilostomes diversified into their environment. Thus, the microecological record of preserved competitive interactions between cyclostome and cheilostome bryozoans and the macroevolutionary record of global diversity are consistent in regard to competition as a significant influence on diversity histories of post-Paleozoic bryozoans.

Selection by mating competitiveness improves the performance of Anastrepha ludens males of the genetic sexing strain Tapachula-7.

PubMed

Quintero-Fong, L; Toledo, J; Ruiz, L; Rendón, P; Orozco-Dávila, D; Cruz, L; Liedo, P

2016-10-01

The sexual performance of Anastrepha ludens males of the Tapachula-7 genetic sexing strain, produced via selection based on mating success, was compared with that of males produced without selection in competition with wild males. Mating competition, development time, survival, mass-rearing quality parameters and pheromone production were compared. The results showed that selection based on mating competitiveness significantly improved the sexual performance of offspring. Development time, survival of larvae, pupae and adults, and weights of larvae and pupae increased with each selection cycle. Differences in the relative quantity of the pheromone compounds (Z)-3-nonenol and anastrephin were observed when comparing the parental males with the F4 and wild males. The implications of this colony management method on the sterile insect technique are discussed.

Effects of Behavioural Strategy on the Exploitative Competition Dynamics.

PubMed

Nguyen-Ngoc, Doanh; Nguyen-Phuong, Thuy

2016-12-01

We investigate a system of two species exploiting a common resource. We consider both abiotic (i.e. with a constant resource supply rate) and biotic (i.e. with resource reproduction and self-limitation) resources. We are interested in the asymmetric competition where a given consumer is the locally superior resource exploiter (LSE) and the other is the locally inferior resource exploiter (LIE). They also interact directly via interference competition in the sense that LIE individuals can use two opposite strategies to compete with LSE individuals: we assume, in the first case, that LIE uses an avoiding strategy, i.e. LIE individuals go to a non-competition patch to avoids competition with LSE individuals, and in the second one, LIE uses an aggressive strategy, i.e. being very aggressive so that LSE individuals have to go to a non-competition patch. We further assume that there is no resource in the non-competition patch so that individuals have to come back to the competition patch for their maintenance, and the migration process acts on a fast time scale in comparison with demography and competition processes. The models show that being aggressive is efficient for LIE's survival and even provoke global extinction of the LSE and this result does not depend on the nature of resource.

The effects of competition on achievement motivation in Chinese classrooms.

PubMed

Lam, Shui-fong; Yim, Pui-shan; Law, Josephine S F; Cheung, Rebecca W Y

2004-06-01

Laboratory studies have consistently found that competition induces performance goals and affects learning motivation. However, the ecological validity of these results is yet to be established. There is a need for investigation of whether the results hold in both the classroom context and non-Western culture. The study investigated the effects of competition on learning motivation among Chinese students in an authentic classroom setting. The participants were 52 students of grade 7 from two Hong Kong secondary schools. They were randomly assigned to either competitive or non-competitive conditions in a 2-hour Chinese typewriting course. Students in the competitive condition performed better in easy tasks than their counterparts in the non-competitive condition. However, they were more performance-oriented and more likely to sacrifice learning opportunities for better performance. They were also prone to have worse self-evaluation after failure. Although there were no statistically significant differences between the two conditions in task enjoyment and achievement attribution, the direction of the differences was consistently unfavourable to students in the competitive condition. The findings were consistent with the predictions of goal theory. Competitiveness induces performance goals and worse self-evaluation after failure among Chinese students in a classroom setting, as was found with Western students in a laboratory setting.

Evolutionary implications of interspecific variation in a maternal effect: a meta-analysis of yolk testosterone response to competition

PubMed Central

Navara, Kristen J.

2016-01-01

Competition between conspecifics during the breeding season can result in behavioural and physiological programming of offspring via maternal effects. For birds, in which maternal effects are best studied, it has been claimed that exposure to increased competition causes greater deposition of testosterone into egg yolks, which creates faster growing, more aggressive offspring; such traits are thought to be beneficial for high-competition environments. Nevertheless, not all species show a positive relationship between competitive interactions and yolk testosterone, and an explanation for this interspecific variation is lacking. We here test if the magnitude and direction of maternal testosterone allocated to eggs in response to competition can be explained by life-history traits while accounting for phylogenetic relationships. We performed a meta-analysis relating effect size of yolk testosterone response to competition with species coloniality, nest type, parental effort and mating type. We found that effect size was moderated by coloniality and nest type; colonial species and those with open nests allocate less testosterone to eggs when in more competitive environments. Applying a life-history perspective helps contextualize studies showing little or negative responses of yolk testosterone to competition and improves our understanding of how variation in this maternal effect may have evolved. PMID:28018636

The relation between narcissism and laboratory aggression is not contingent on environmental cues of competition.

PubMed

Hyatt, Courtland S; Weiss, Brandon M; Carter, Nathan T; Zeichner, Amos; Miller, Joshua D

2018-06-18

Narcissism has been robustly linked to self-report and lab-based measures of aggression. However, less is known about the role that a competitive context may play in the relations found between narcissism and aggression as measured in behavioral paradigms. In circumstances of competition, narcissistic individuals may be particularly attuned to external indicators of status and use aggression as a way of asserting power and a motivation to "win," rather than to do harm. The goal of the present study was to test the role of competition in understanding the relation between narcissism and related traits (i.e., psychopathy) and aggression by manipulating cues of competition. First, participants (N = 220) completed questionnaires to assess levels of trait narcissism and associated variables (e.g., psychopathy, five-factor model traits, and self-esteem). In a separate session, participants were randomly assigned to interact with an ostensible confederate under the guise of either a competitive or noncompetitive interaction, and then were given the opportunity to administer electric shocks to their partner. Results suggest that the antagonistic and grandiose features of narcissism were significantly related to aggression in both conditions, as was the antagonism factor of psychopathy and (low) Agreeableness dimension of the five-factor model. However, tests of moderation found no significant interaction effects between narcissism and condition in the hypothesized direction (and a few in the opposite direction such that narcissism was more strongly related in the noncompetition condition). Findings are discussed in terms of the importance of antagonism in predicting antisocial outcomes such as aggression. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Self-organizing path integration using a linked continuous attractor and competitive network: path integration of head direction.

PubMed

Stringer, Simon M; Rolls, Edmund T

2006-12-01

A key issue is how networks in the brain learn to perform path integration, that is update a represented position using a velocity signal. Using head direction cells as an example, we show that a competitive network could self-organize to learn to respond to combinations of head direction and angular head rotation velocity. These combination cells can then be used to drive a continuous attractor network to the next head direction based on the incoming rotation signal. An associative synaptic modification rule with a short term memory trace enables preceding combination cell activity during training to be associated with the next position in the continuous attractor network. The network accounts for the presence of neurons found in the brain that respond to combinations of head direction and angular head rotation velocity. Analogous networks in the hippocampal system could self-organize to perform path integration of place and spatial view representations.

Repetitive head impacts do not affect postural control following a competitive athletic season.

PubMed

Murray, Nicholas G; Grimes, Katelyn E; Shiflett, Eric D; Munkasy, Barry A; D'Amico, Nathan R; Mormile, Megan E; Powell, Douglas W; Buckley, Thomas A

2017-10-03

Evidence suggests that Repetitive Head Impacts (RHI) directly influence the brain over the course of a single contact collision season yet do not significantly impact a player's performance on the standard clinical concussion assessment battery. The purpose of this study was to investigate changes in static postural control after a season of RHI in Division I football athletes using more sensitive measures of postural control as compared to a non-head contact sports. Fourteen Division I football players (CON) (age=20.4±1.12years) and fourteen non-contact athletes (NON) (2 male, 11 female; age=19.85±1.21years) completed a single trial of two minutes of eyes open quiet upright stance on a force platform (1000Hz) prior to athletic participation (PRE) and at the end of the athletic season (POST). All CON athletes wore helmets outfitted with Head Impact Telemetry (HIT) sensors and total number of RHI and linear accelerations forces of each RHI were recorded. Center of pressure root mean square (RMS), peak excursion velocity (PEV), and sample entropy (SampEn) in the anteroposterior (AP) and mediolateral (ML) directions were calculated. CON group experienced 649.5±496.8 mean number of impacts, 27.1±3.0 mean linear accelerations, with ≈1% of total player impacts exceeded 98g over the course of the season. There were no significant interactions for group x time RMS in the AP (p=0.434) and ML (p=0.114) directions, PEV in the AP (p=0.262) and ML (p=0.977) directions, and SampEn in the AP (p=0.499) and ML (p=0.984) directions. In addition, no significant interactions for group were observed for RMS in the AP (p=0.105) and ML (p=0.272) directions, PEV in the AP (p=0.081) and ML (p=0.143) directions, and SampEn in the AP (p=0.583) and ML (p=0.129) directions. These results suggest that over the course of a single competitive season, RHI do not negatively impact postural control even when measured with sensitive non-linear metrics. Copyright © 2017 Elsevier B.V. All rights reserved.

Mexican Immigration to Southern California: Issues of Job Competition and Worker Mobility. Impacts of Immigration in California.

ERIC Educational Resources Information Center

Manson, Donald M.; And Others

Characteristics that would tend to place Mexican immigrants in direct competition with native workers for jobs at the bottom of the wage and skill hierarchy are their numbers, their largely undocumented status, low education and skill levels, and poor English-speaking ability. Using regression analysis, 1980 Census data were analyzed to determine…

Kinetic mechanism of ATP-sulphurylase from rat chondrosarcoma.

PubMed Central

Lyle, S; Geller, D H; Ng, K; Westley, J; Schwartz, N B

1994-01-01

ATP-sulphurylase catalyses the production of adenosine 5'-phosphosulphate (APS) from ATP and free sulphate with the release of PPi. APS kinase phosphorylates the APS intermediate to produce adenosine 3'-phosphate 5'-phosphosulphate (PAPS). The kinetic mechanism of rat chondrosarcoma ATP-sulphurylase was investigated by steady-state methods in the physiologically forward direction as well as the reverse direction. The sulphurylase activity was coupled to APS kinase activity in order to overcome the thermodynamic constraints of the sulphurylase reaction in the forward direction. Double-reciprocal initial-velocity plots for the forward sulphurylase intersect to the left of the ordinate for this reaction. KmATP and Kmsulphate were found to be 200 and 97 microM respectively. Chlorate, a competitive inhibitor with respect to sulphate, showed uncompetitive inhibition with respect to ATP with an apparent Ki of 1.97 mM. Steady-state data from experiments in the physiologically reverse direction also yielded double-reciprocal initial-velocity patterns that intersect to the left of the ordinate axis, with a KmAPS of 39 microM and a Kmpyrophosphate of 18 microM. The results of steady-state experiments in which Mg2+ was varied indicated that the true substrate is the MgPPi complex. An analogue of APS, adenosine 5'-[beta-methylene]phosphosulphate, was a linear inhibitor competitive with APS and non-competitive with respect to MgPPi. The simplest formal mechanism that agrees with all the data is an ordered steady-state single displacement with MgATP as the leading substrate in the forward direction and APS as the leading substrate in the reverse direction. PMID:8042976

Imaging dynamic fingerprints of competing E2 and SN2 reactions.

PubMed

Carrascosa, Eduardo; Meyer, Jennifer; Zhang, Jiaxu; Stei, Martin; Michaelsen, Tim; Hase, William L; Yang, Li; Wester, Roland

2017-06-21

The competition between bimolecular nucleophilic substitution and base-induced elimination is of fundamental importance for the synthesis of pure samples in organic chemistry. Many factors that influence this competition have been identified over the years, but the underlying atomistic dynamics have remained difficult to observe. We present product velocity distributions for a series of reactive collisions of the type X -  + RY with X and Y denoting the halogen atoms fluorine, chlorine and iodine. By increasing the size of the residue R from methyl to tert-butyl in several steps, we find that the dynamics drastically change from backward to dominant forward scattering of the leaving ion relative to the reactant RY velocity. This characteristic fingerprint is also confirmed by direct dynamics simulations for ethyl as residue and attributed to the dynamics of elimination reactions. This work opens the door to a detailed atomistic understanding of transformation reactions in even larger systems.The competition between chemical reactions critically affects our natural environment and the synthesis of new materials. Here, the authors present an approach to directly image distinct fingerprints of essential organic reactions and monitor their competition as a function of steric substitution.

Growth Versus Government Management Improvement During Economic Downturn

NASA Astrophysics Data System (ADS)

Podobnik, Boris; Baaquie, Belal E.; Bishop, Steven; Njavro, Djuro; Li, Baowen

2013-04-01

In estimating how economic growth depends on various inputs, economists commonly use long periods of data encompassing both main extremes to fluctuations in the economy: recession and expansion. Here we focus on recession years because during expansion even countries with bad economic policies may experience large growth. Specifically, we study how growth depends on the proportion of public-sector workforce, p and competitiveness, quantified by the Global Competitiveness Index, GCI. For the 2008-2011 economic downturn and for 57 countries, we find that the growth rate of GDP per capita, g, decreases with p, and increases with ΔGCI. Further, more competitive countries attract more foreign direct investments per capita, I, than less competitive countries, where I ~ GCIα. We propose a production function, divided into the private and public sectors, where GDP depends on market capitalization, the public (private)-sector workforce, and competitiveness level, used to quantify the public sector efficiency.

Growth versus government management improvement during economic downturn.

PubMed

Podobnik, Boris; Baaquie, Belal E; Bishop, Steven; Njavro, Djuro; Li, Baowen

2013-01-01

In estimating how economic growth depends on various inputs, economists commonly use long periods of data encompassing both main extremes to fluctuations in the economy: recession and expansion. Here we focus on recession years because during expansion even countries with bad economic policies may experience large growth. Specifically, we study how growth depends on the proportion of public-sector workforce, p and competitiveness, quantified by the Global Competitiveness Index, GCI. For the 2008-2011 economic downturn and for 57 countries, we find that the growth rate of GDP per capita, g, decreases with p, and increases with ΔGCI. Further, more competitive countries attract more foreign direct investments per capita, I, than less competitive countries, where I is proportional to GCI(α). We propose a production function, divided into the private and public sectors, where GDP depends on market capitalization, the public (private)-sector workforce, and competitiveness level, used to quantify the public sector efficiency.

Liver overload in Brazilian triathletes after half-ironman competition is related muscle fatigue.

PubMed

Bürger-Mendonça, Marcos; Bielavsky, Monica; Barbosa, Fernanda C R

2008-01-01

Triathlon competition is dependent on the athletes' ability to perform each discipline at optimal time, without excessive fatigue influencing the next one. Determine the effects of a long distance triathlon on biochemistry parameters related to liver function. Blood samples from six athletes were collected before (T = 0) and immediately after the triathlon competition (T = 1). AST, ALT and alkaline phosphatase (ALP) values were assessed. Significant changes after triathlon competition were found for AST and ALP and no significant changes were found for ALT over time. A series of metabolically alterations, mainly related to energy production and also to muscle and skeletal adaptations occurs during and after strenuous exercise. The altered status of those metabolical changes cannot directly reflect the intensity of any possible muscular or hepatic damage or overload and elevated AST/ALT ratio is better associated to skeletal muscle lesion during competition.

Growth Versus Government Management Improvement During Economic Downturn

PubMed Central

Podobnik, Boris; Baaquie, Belal E.; Bishop, Steven; Njavro, Djuro; Li, Baowen

2013-01-01

In estimating how economic growth depends on various inputs, economists commonly use long periods of data encompassing both main extremes to fluctuations in the economy: recession and expansion. Here we focus on recession years because during expansion even countries with bad economic policies may experience large growth. Specifically, we study how growth depends on the proportion of public-sector workforce, p and competitiveness, quantified by the Global Competitiveness Index, GCI. For the 2008–2011 economic downturn and for 57 countries, we find that the growth rate of GDP per capita, g, decreases with p, and increases with ΔGCI. Further, more competitive countries attract more foreign direct investments per capita, I, than less competitive countries, where I ∝ GCIα. We propose a production function, divided into the private and public sectors, where GDP depends on market capitalization, the public (private)-sector workforce, and competitiveness level, used to quantify the public sector efficiency. PMID:23563321

FINANCIAL LITERACY, FINANCIAL EDUCATION AND ECONOMIC OUTCOMES

PubMed Central

Hastings, Justine S.; Madrian, Brigitte C.; Skimmyhorn, William L.

2013-01-01

In this article we review the literature on financial literacy, financial education, and consumer financial outcomes. We consider how financial literacy is measured in the current literature, and examine how well the existing literature addresses whether financial education improves financial literacy or personal financial outcomes. We discuss the extent to which a competitive market provides incentives for firms to educate consumers or offer products that facilitate informed choice. We review the literature on alternative policies to improve financial outcomes, and compare the evidence to evidence on the efficacy and cost of financial education. Finally, we discuss directions for future research. PMID:23991248

FINANCIAL LITERACY, FINANCIAL EDUCATION AND ECONOMIC OUTCOMES.

PubMed

Hastings, Justine S; Madrian, Brigitte C; Skimmyhorn, William L

2013-05-01

In this article we review the literature on financial literacy, financial education, and consumer financial outcomes. We consider how financial literacy is measured in the current literature, and examine how well the existing literature addresses whether financial education improves financial literacy or personal financial outcomes. We discuss the extent to which a competitive market provides incentives for firms to educate consumers or offer products that facilitate informed choice. We review the literature on alternative policies to improve financial outcomes, and compare the evidence to evidence on the efficacy and cost of financial education. Finally, we discuss directions for future research.

The Balloon Popping Problem Revisited: Lower and Upper Bounds

NASA Astrophysics Data System (ADS)

Jung, Hyunwoo; Chwa, Kyung-Yong

We consider the balloon popping problem introduced by Immorlica et al. in 2007 [13]. This problem is directly related to the problem of profit maximization in online auctions, where an auctioneer is selling a collection of identical items to anonymous unit-demand bidders. The auctioneer has the full knowledge of bidders’ private valuations for the items and tries to maximize his profit. Compared with the profit of fixed price schemes, the competitive ratio of Immorlica et al.’s algorithm was in the range [1.64, 4.33]. In this paper, we narrow the gap to [1.659, 2].

Applying simulation to optimize plastic molded optical parts

NASA Astrophysics Data System (ADS)

Jaworski, Matthew; Bakharev, Alexander; Costa, Franco; Friedl, Chris

2012-10-01

Optical injection molded parts are used in many different industries including electronics, consumer, medical and automotive due to their cost and performance advantages compared to alternative materials such as glass. The injection molding process, however, induces elastic (residual stress) and viscoelastic (flow orientation stress) deformation into the molded article which alters the material's refractive index to be anisotropic in different directions. Being able to predict and correct optical performance issues associated with birefringence early in the design phase is a huge competitive advantage. This paper reviews how to apply simulation analysis of the entire molding process to optimize manufacturability and part performance.

The importance of motivation, weapons, and foul odors in driving encounter competition in carnivores.

PubMed

Allen, Maximilian L; Wilmers, Christopher C; Elbroch, L Mark; Golla, Julie M; Wittmer, Heiko U

2016-08-01

Encounter competition is interference competition in which animals directly contend for resources. Ecological theory predicts the trait that determines the resource holding potential (RHP), and hence the winner of encounter competition, is most often body size or mass. The difficulties of observing encounter competition in complex organisms in natural environments, however, has limited opportunities to test this theory across diverse species. We studied the outcome of encounter competition contests among mesocarnivores at deer carcasses in California to determine the most important variables for winning these contests. We found some support for current theory in that body mass is important in determining the winner of encounter competition, but we found that other factors including hunger and species-specific traits were also important. In particular, our top models were "strength and hunger" and "size and hunger," with models emphasizing the complexity of variables influencing outcomes of encounter competition. In addition, our wins above predicted (WAP) statistic suggests that an important aspect that determines the winner of encounter competition is species-specific advantages that increase their RHP, as bobcats (Lynx rufus) and spotted skunks (Spilogale gracilis) won more often than predicted based on mass. In complex organisms, such as mesocarnivores, species-specific adaptations, including strategic behaviors, aggressiveness, and weapons, contribute to competitive advantages and may allow certain species to take control or defend resources better than others. Our results help explain how interspecific competition shapes the occurrence patterns of species in ecological communities. © 2016 by the Ecological Society of America.

Antagonistic interactions between plant competition and insect herbivory.

PubMed

Schädler, Martin; Brandl, Roland; Haase, Josephine

2007-06-01

Interspecific competition between plants and herbivory by specialized insects can have synergistic effects on the growth and performance of the attacked host plant. We tested the hypothesis that competition between plants may also negatively affect the performance of herbivores as well as their top-down effect on the host plant. In such a case, the combined effects of competition and herbivory may be less than expected from a simple multiplicative response. In other words, competition and herbivory may interact antagonistically. In a greenhouse experiment, Poa annua was grown in the presence or absence of a competitor (either Plantago lanceolata or Trifolium repens), as well as with or without a Poa-specialist aphid herbivore. Both competition and herbivory negatively affected Poa growth. Competition also reduced aphid density on Poa. This effect could in part be explained by changes in the biomass and the nitrogen content of Poa shoots. In treatments with competitors, reduced aphid densities alleviated the negative effect of herbivory on above- and belowground Poa biomass. Hence, we were able to demonstrate an antagonistic interaction between plant-plant interspecific competition and herbivory. However, response indices suggested that antagonistic interactions between competition and herbivory were contingent on the identity of the competitor. We found the antagonistic effect only in treatments with T. repens as the competitor. We conclude that both competitor identity and the herbivore's ability to respond with changes in its density or activity to plant competition affect the magnitude and direction (synergistic vs. antagonistic) of the interaction between competition and herbivory on plant growth.

Demonstration of four immunoassay formats using the array biosensor

NASA Technical Reports Server (NTRS)

Sapsford, Kim E.; Charles, Paul T.; Patterson, Charles H Jr; Ligler, Frances S.

2002-01-01

The ability of a fluorescence-based array biosensor to measure and quantify the binding of an antigen to an immobilized antibody has been demonstrated using the four different immunoassay formats: direct, competitive, displacement, and sandwich. A patterned array of antibodies specific for 2,4,6-trinitrotoluene (TNT) immobilized onto the surface of a planar waveguide and used to measure signals from different antigen concentrations simultaneously. For direct, competitive, and displacement assays, which are one-step assays, measurements were obtained in real time. Dose-response curves were calculated for all four assay formats, demonstrating the array biosensor's ability to quantify the amount of antigen present in solution.

Cooperation, Competition, and the Structure of Student Cliques.

ERIC Educational Resources Information Center

Hansell, Stephen; And Others

Research indicates substantial evidence that, compared with competition, cooperation increases mutual friendliness and contact between individuals. The effects of cooperative and competitive experiences on the structure of student cliques in the classroom were examined. Seven classrooms of fourth-, fifth-, and sixth-grade students (N=117) were…

Sexually selected sentinels? Evidence of a role for intrasexual competition in sentinel behavior

PubMed Central

Walker, Lindsay A.; York, Jenny E.

2016-01-01

Although the evolutionary mechanisms that favor investment in cooperative behaviors have long been a focus of research, comparatively few studies have considered the role that sexual selection may play. For example, evolutionary explanations for sentinel behavior (where 1 individual assumes an elevated position and scans the surroundings while other group members forage nearby) have traditionally focused on the inclusive fitness benefits arising from its effects on predation risk, while its potential role in defense against intrasexual competitors remains largely unexplored. Here, we provide experimental evidence of a role for sentinel behavior in intrasexual competition, in a cooperatively breeding songbird, the white-browed sparrow weaver (Plocepasser mahali). First, dominant males sentinel substantially more than other group members (even when controlling for variation in age and body condition), consistent with a role for sentineling in intrasexual competition for mates and/or territory. Second, experimental playback of an unfamiliar male’s solo song elicited a marked increase in sentineling by the dominant male, and the vocal response to the playback also positively predicted his sentinel effort following the simulated intrusion. A second experiment also suggests that sentineling may facilitate mounting rapid anti-intruder responses, as responses to intruder-playback occurred significantly earlier when the dominant male was sentineling rather than foraging at playback onset. Together, our findings provide rare support for the hypothesis that sentinel behavior plays a role in intrasexual competition, and so highlight the potential for sexually selected direct benefits to shape its expression in this and other social vertebrates. PMID:27656086

77 FR 24373 - International Services Surveys and Direct Investment Surveys Reporting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-24

.... 111012619-2230-03] RIN 0691-AA81 International Services Surveys and Direct Investment Surveys Reporting... services and direct investment surveys, which are provided for by the International Investment and Trade in Services Survey Act (the Act). In addition to the Act, the Omnibus Trade and Competitiveness Act of 1988...

78 FR 9941 - Notice of Determinations Regarding Eligibility To Apply for Worker Adjustment Assistance

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-12

... threatened to become totally or partially separated; (2) the sales or production, or both, of such firm have... like or directly competitive with articles produced or services supplied by such firm have increased... parts produced by such firm are directly incorporated, have increased; (C) imports of articles directly...

32 CFR 22.315 - Merit-based, competitive procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... This OMB policy directive is available at the Internet site http://www.whitehouse.gov/omb/grants/grants... accordance with that OMB policy directive, DoD Components also must post on the Internet any notice under...), the notice need not be posted on the Internet. (3) To comply with an OMB policy directive entitled...

32 CFR 22.315 - Merit-based, competitive procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... This OMB policy directive is available at the Internet site http://www.whitehouse.gov/omb/grants/grants... accordance with that OMB policy directive, DoD Components also must post on the Internet any notice under...), the notice need not be posted on the Internet. (3) To comply with an OMB policy directive entitled...

Comparative evaluation of rail and truck fuel efficiency on competitive corridors : final report

DOT National Transportation Integrated Search

2009-11-19

This study provides a comparative evaluation of rail and truck fuel efficiency on corridors and services in which both modes compete. For the purposes of this study, competitive movements are defined as those of the same commodity having the same (or...

Consumer interaction strength may limit the diversifying effect of intraspecific competition: a test in alewife (Alosa pseudoharengus).

PubMed

Jones, Andrew W; Post, David M

2013-06-01

Intraspecific competition is considered a principal driver of dietary variation, but empirical studies provide mixed support for this mechanism. Here we link comparative and experimental work testing the effects of competition and resource availability on the dietary variation of the alewife (Alosa pseudoharengus). The alewife, a consumer with extreme effects on its resources, was specifically utilized to additionally test the idea that strong interactions between a consumer and its resources can diminish the diversifying effect of competition. First, we compared the short- and long-term diet measures of wild populations across a wide range of densities. Second, in a pair of large-scale field mesocosm experiments, we explored the influence of competition and interaction strength on alewife dietary variation. Results from a whole-lake comparison and field experiments indicated that increasing competition was negatively correlated with population dietary variation. Further, altering the strength of the interaction between the alewife and its prey via prey supplementation eliminated this negative relationship. Collectively, our results suggest that competitive interactions may not drive dietary diversification in the alewife and, potentially, in other highly effective consumers. Our results also indicate that further consideration of the strength of species interactions (and the consumer traits that underlie them) would improve our understanding of the link between intraspecific competition and variation.

Competing while cooperating with the same others: The consequences of conflicting demands in co-opetition.

PubMed

Landkammer, Florian; Sassenberg, Kai

2016-12-01

Numerous studies comparing the effects of competition and cooperation demonstrated that competition is detrimental on the social level. However, instead of purely competing, many social contexts require competing while cooperating with the same social target. The current work examined the consequences of such "co-opetition" situations between individuals. Because having to compete and to cooperate with the same social target constitutes conflicting demands, co-opetition should lead to more flexibility, such as (a) less rigid transfer effects of competitive behavior and (b) less rigidity/more flexibility in general. Supporting these predictions, Studies 1a and 1b demonstrated that co-opetition did not elicit competitive behavior in a subsequent task (here: enhanced deceiving of uninvolved others). Study 2 showed that adding conflicting demands (independent of social interdependence) to competition likewise elicits less competitive transfer than competition without such conflicting demands. Beyond that, co-opetition reduced rigid response tendencies during a classification task in Studies 3a and 3b and enhanced flexibility during brainstorming in Study 4, compared with other forms of interdependence. Together, these results suggest that co-opetition leads to more flexible behavior when individuals have to reconcile conflicting demands. Implications for research on social priming, interdependence and competition in everyday life are discussed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

The possibility of coexistence and co-development in language competition: ecology-society computational model and simulation.

PubMed

Yun, Jian; Shang, Song-Chao; Wei, Xiao-Dan; Liu, Shuang; Li, Zhi-Jie

2016-01-01

Language is characterized by both ecological properties and social properties, and competition is the basic form of language evolution. The rise and decline of one language is a result of competition between languages. Moreover, this rise and decline directly influences the diversity of human culture. Mathematics and computer modeling for language competition has been a popular topic in the fields of linguistics, mathematics, computer science, ecology, and other disciplines. Currently, there are several problems in the research on language competition modeling. First, comprehensive mathematical analysis is absent in most studies of language competition models. Next, most language competition models are based on the assumption that one language in the model is stronger than the other. These studies tend to ignore cases where there is a balance of power in the competition. The competition between two well-matched languages is more practical, because it can facilitate the co-development of two languages. A third issue with current studies is that many studies have an evolution result where the weaker language inevitably goes extinct. From the integrated point of view of ecology and sociology, this paper improves the Lotka-Volterra model and basic reaction-diffusion model to propose an "ecology-society" computational model for describing language competition. Furthermore, a strict and comprehensive mathematical analysis was made for the stability of the equilibria. Two languages in competition may be either well-matched or greatly different in strength, which was reflected in the experimental design. The results revealed that language coexistence, and even co-development, are likely to occur during language competition.

Skating mechanics of change-of-direction manoeuvres in ice hockey players.

PubMed

Fortier, Antoine; Turcotte, René A; Pearsall, David J

2014-11-01

Ice hockey requires rapid transitions between skating trajectories to effectively navigate about the ice surface. Player performance relates in large part to effective change-of-direction manoeuvres, but little is known about how those skills are performed mechanically and the effect of equipment design on them. The purpose of this study was to observe the kinetics involved in those manoeuvres as well as to compare whether kinetic differences may result between two skate models of varying ankle mobility. Eight subjects with competitive ice hockey playing experience performed rapid lateral (90°) left and right change-of-direction manoeuvres. Kinetic data were collected using force strain gauge transducers on the blade holders of the skates. Significantly greater forces were applied by the outside skate (50-70% body weight, %BW) in comparison to the inside skate (12-24%BW, p < 0.05). Skate model and turn direction had no main effect, though significant mixed interactions between leg side (inside/outside) with skate model or turn direction (p < 0.05) were observed, with a trend for left-turn dominance. This study demonstrates the asymmetric dynamic behaviour inherent in skating change-of-direction tasks.

Hidden profiles and concealed information: strategic information sharing and use in group decision making.

PubMed

Toma, Claudia; Butera, Fabrizio

2009-06-01

Two experiments investigated the differential impact of cooperation and competition on strategic information sharing and use in a three-person group decision-making task. Information was distributed in order to create a hidden profile so that disconfirmation of group members' initial preferences was required to solve the task. Experiment 1 revealed that competition, compared to cooperation, led group members to withhold unshared information, a difference that was not significant for shared information. In competition, compared to cooperation, group members were also more reluctant to disconfirm their initial preferences. Decision quality was lower in competition than in cooperation, this effect being mediated by disconfirmation use and not by information sharing. Experiment 2 replicated these findings and revealed the role of mistrust in predicting strategic information sharing and use in competition. These results support a motivated information processing approach of group decision making.

Association of competitive and recreational sport participation with cardiac events in patients with arrhythmogenic right ventricular cardiomyopathy: results from the North American multidisciplinary study of arrhythmogenic right ventricular cardiomyopathy

PubMed Central

Ruwald, Anne-Christine; Marcus, Frank; Estes, N.A. Mark; Link, Mark; McNitt, Scott; Polonsky, Bronislava; Calkins, Hugh; Towbin, Jeffrey A.; Moss, Arthur J.; Zareba, Wojciech

2015-01-01

Aims It has been proposed that competitive sport increases the risk of ventricular tachyarrhythmias (VTA) and death in patients with arrhythmogenic right-ventricular cardiomyopathy (ARVC). However, it is unknown whether this only applies to competitive sport or if recreational sports activity also increases the risk of VTA/death. Methods and results Probands diagnosed with ARVC according to the 2010 task force criteria for ARVC (n = 108) were included in the current analysis. At the time of enrolment, study participants were questioned about exercise level prior to and after ARVC diagnosis, within three categories of sports participation: competitive (n = 41), recreational (n = 48), and inactive (n = 19). Competitive sport was associated with a significantly higher risk of VTA/death when compared with both recreational sport [HR = 1.99 (1.21–3.28), P = 0.007] and inactive patients [HR = 2.05 (1.07–3.91), P = 0.030]. No increased risk of VTA/death was associated with recreational sport when compared with patients who were inactive [HR = 1.03 (0.54–1.97), P = 0.930]. Symptoms developed at an earlier age in patients who participated in competitive sport (30 ± 12 years), when compared with patients who participated in recreational sport (38 ± 17 years) (P = 0.015) and inactive patients (41 ± 11 years) (P = 0.002). No difference in age at first symptom was seen between patients who participated in recreational sport and inactive patients (P = 0.651). Conclusion Competitive sport was associated with a two-fold increased risk of VTA/death, and earlier presentation of symptoms, when compared with inactive patients, and to patients who participated in recreational sport. When compared with inactive patients, recreational sport was not associated with earlier onset of symptoms or increased risk of VTA/death. Clinical trials.gov identifier NCT00024505. PMID:25896080

Increasing Competition for Spares within AFLC (Air Force Logistics Center). Revision.

DTIC Science & Technology

1982-11-30

Managers 45 On Competing the Production of Weapon Systems 46 Sole Source and Competitive Price Trends in Spare Parts Acquisition 47 Controlled...future directions in research and policy . 3- TOPIC: Acquisition TYPE: AFIT Thesis TITLE: Spares Acquisition Integrated with Production and Its...evaluate Air Force management policies , procedures, practices, and controls over the acquisition and pricing of spare parts. Specific objectives

A methodology for evaluation of parent-mutant competition using a generalized non-linear ecosystem model

Treesearch

Raymond L. Czaplewski

1973-01-01

A generalized, non-linear population dynamics model of an ecosystem is used to investigate the direction of selective pressures upon a mutant by studying the competition between parent and mutant populations. The model has the advantages of considering selection as operating on the phenotype, of retaining the interaction of the mutant population with the ecosystem as a...

Competitive market for multiple firms and economic crisis

NASA Astrophysics Data System (ADS)

Tao, Yong

2010-09-01

The origin of economic crises is a key problem for economics. We present a model of long-run competitive markets to show that the multiplicity of behaviors in an economic system, over a long time scale, emerge as statistical regularities (perfectly competitive markets obey Bose-Einstein statistics and purely monopolistic-competitive markets obey Boltzmann statistics) and that how interaction among firms influences the evolutionary of competitive markets. It has been widely accepted that perfect competition is most efficient. Our study shows that the perfectly competitive system, as an extreme case of competitive markets, is most efficient but not stable, and gives rise to economic crises as society reaches full employment. In the economic crisis revealed by our model, many firms condense (collapse) into the lowest supply level (zero supply, namely, bankruptcy status), in analogy to Bose-Einstein condensation. This curious phenomenon arises because perfect competition (homogeneous competitions) equals symmetric (indistinguishable) investment direction, a fact abhorred by nature. Therefore, we urge the promotion of monopolistic competition (heterogeneous competitions) rather than perfect competition. To provide early warning of economic crises, we introduce a resolving index of investment, which approaches zero in the run-up to an economic crisis. On the other hand, our model discloses, as a profound conclusion, that the technological level for a long-run social or economic system is proportional to the freedom (disorder) of this system; in other words, technology equals the entropy of system. As an application of this concept, we give a possible answer to the Needham question: “Why was it that despite the immense achievements of traditional China it had been in Europe and not in China that the scientific and industrial revolutions occurred?”

Competitive market for multiple firms and economic crisis.

PubMed

Tao, Yong

2010-09-01

The origin of economic crises is a key problem for economics. We present a model of long-run competitive markets to show that the multiplicity of behaviors in an economic system, over a long time scale, emerge as statistical regularities (perfectly competitive markets obey Bose-Einstein statistics and purely monopolistic-competitive markets obey Boltzmann statistics) and that how interaction among firms influences the evolutionary of competitive markets. It has been widely accepted that perfect competition is most efficient. Our study shows that the perfectly competitive system, as an extreme case of competitive markets, is most efficient but not stable, and gives rise to economic crises as society reaches full employment. In the economic crisis revealed by our model, many firms condense (collapse) into the lowest supply level (zero supply, namely, bankruptcy status), in analogy to Bose-Einstein condensation. This curious phenomenon arises because perfect competition (homogeneous competitions) equals symmetric (indistinguishable) investment direction, a fact abhorred by nature. Therefore, we urge the promotion of monopolistic competition (heterogeneous competitions) rather than perfect competition. To provide early warning of economic crises, we introduce a resolving index of investment, which approaches zero in the run-up to an economic crisis. On the other hand, our model discloses, as a profound conclusion, that the technological level for a long-run social or economic system is proportional to the freedom (disorder) of this system; in other words, technology equals the entropy of system. As an application of this concept, we give a possible answer to the Needham question: "Why was it that despite the immense achievements of traditional China it had been in Europe and not in China that the scientific and industrial revolutions occurred?"

Are sick individuals weak competitors? Competitive ability of snails parasitized by a gigantism-inducing trematode.

PubMed

Seppälä, Otto; Karvonen, Anssi; Kuosa, Marja; Haataja, Maarit; Jokela, Jukka

2013-01-01

Parasitized individuals are often expected to be poor competitors because they are weakened by infections. Many trematode species, however, although extensively exploiting their mollusc hosts, also induce gigantism (increased host size) by diverting host resources towards growth instead of reproduction. In such systems, alternatively to reduced competitive ability due to negative effects of parasitism on host performance, larger size could allow more efficient resource acquisition and thus increase the relative competitive ability of host individuals. We addressed this hypothesis by testing the effect of a trematode parasite Diplostomum pseudospathaceum on the competitive ability of its snail host Lymnaea stagnalis. We experimentally examined the growth of snails kept in pairs in relation to their infection status and intensity of resource competition (i.e. food availability). We found that parasitized snails grew faster and their reproduction was reduced compared to unparasitized individuals indicating parasite-induced gigantism. However, growth of the snails was faster when competing with parasitized individuals compared to unparasitized snails indicating reduced competitive ability due to parasitism. The latter effect, however, was relatively weak suggesting that the effects of the parasite on snail physiology may partly override each other in determining competitive ability.

Competitive disadvantage makes attitudes towards rape less negative.

PubMed

Nunes, Kevin L; Pettersen, Cathrine

2011-10-12

Evolutionary theorists have argued that perceived competitive disadvantage may lead to more positive evaluation of, and greater likelihood of engaging in, risky and antisocial behavior. However, experimental studies have not yet examined the effects of competitive disadvantage on perceptions of rape. In the current study, we created a manipulation of perceived competitive status to test its effects on beliefs about rape. In one condition, participants were made to feel disadvantaged relative to male peers in terms of financial, physical, and intellectual power, whereas in the other condition they were made to feel advantaged. Participants were 120 heterosexual male undergraduate students. The manipulation was effective; compared to participants in the advantage condition, those in the disadvantage condition rated themselves as significantly worse off financially, shorter, in worse physical shape, and as having lower course marks than the average male student at the university. Compared to perceived competitive advantage, perceived disadvantage led to less negative attitudes towards rape. However, perceived competitive status did not significantly affect justifications and excuses for rape. Future studies using similar experimental manipulations can complement correlational studies and may contribute to greater clarity, precision, and sophistication of research and theory on the role of competitive disadvantage in rape.

Are Sick Individuals Weak Competitors? Competitive Ability of Snails Parasitized by a Gigantism-Inducing Trematode

PubMed Central

Seppälä, Otto; Karvonen, Anssi; Kuosa, Marja; Haataja, Maarit; Jokela, Jukka

2013-01-01

Parasitized individuals are often expected to be poor competitors because they are weakened by infections. Many trematode species, however, although extensively exploiting their mollusc hosts, also induce gigantism (increased host size) by diverting host resources towards growth instead of reproduction. In such systems, alternatively to reduced competitive ability due to negative effects of parasitism on host performance, larger size could allow more efficient resource acquisition and thus increase the relative competitive ability of host individuals. We addressed this hypothesis by testing the effect of a trematode parasite Diplostomum pseudospathaceum on the competitive ability of its snail host Lymnaea stagnalis. We experimentally examined the growth of snails kept in pairs in relation to their infection status and intensity of resource competition (i.e. food availability). We found that parasitized snails grew faster and their reproduction was reduced compared to unparasitized individuals indicating parasite-induced gigantism. However, growth of the snails was faster when competing with parasitized individuals compared to unparasitized snails indicating reduced competitive ability due to parasitism. The latter effect, however, was relatively weak suggesting that the effects of the parasite on snail physiology may partly override each other in determining competitive ability. PMID:24205383

Sperm competition and reproductive mode influence sperm dimensions and structure among snakes.

PubMed

Tourmente, Maximiliano; Gomendio, Montserrat; Roldan, Eduardo R S; Giojalas, Laura C; Chiaraviglio, Margarita

2009-10-01

The role of sperm competition in increasing sperm length is a controversial issue, because findings from different taxa seem contradictory. We present a comparative study of 25 species of snakes with different levels of sperm competition to test whether it influences the size and structure of different sperm components. We show that, as levels of sperm competition increase, so does sperm length, and that this elongation is largely explained by increases in midpiece length. In snakes, the midpiece is comparatively large and it contains structures, which in other taxa are present in the rest of the flagellum, suggesting that it may integrate some of its functions. Thus, increases in sperm midpiece size would result in more energy as well as greater propulsion force. Sperm competition also increases the area occupied by the fibrous sheath and outer dense fibers within the sperm midpiece, revealing for the first time an effect upon structural elements within the sperm. Finally, differences in male-male encounter rates between oviparous and viviparous species seem to lead to differences in levels of sperm competition. We conclude that the influence of sperm competition upon different sperm components varies between taxa, because their structure and function is different.

When the ball is in the female's court: How the scramble-competition mating system of the North American red squirrel has shaped male physiology and testosterone dynamics.

PubMed

Boonstra, Rudy; Dušek, Adam; Lane, Jeffrey E; Boutin, Stan

2017-10-01

Male reproductive success in most mammals is determined by their success in direct inter-male competition through aggression and conflict, resulting in female-defense mating systems being predominant. This is linked to male testosterone levels and its dynamics. However, in certain environments, a scramble-competition mating system has evolved, where female reproductive behavior takes precedence and male testosterone dynamics are unlikely to be related to inter-male competition. We studied the North American red squirrel (Tamiasciurus hudsonicus), a species with a well-established scramble-competition system. Using an ACTH hormonal challenge protocol as a proxy for competitive interactions, we compared the testosterone dynamics in breeding males in late winter with that in nonbreeding males in late spring in the Yukon. To gain an integrated picture of their physiological state, we also assessed changes in their stress response, body mass, energy mobilization, and indices of immune function. Testosterone levels at the base bleed were high in breeding males (2.72ng/mL) and virtually absent in non-breeding males (0.04ng/mL). Breeding males were in better condition (heavier body mass, higher hematocrit, and higher erythrocytes), had higher indices of immune function (neutrophil:lymphocyte ratio), but a similar ability to mobilize energy (glucose) compared with non-breeding males. Though total cortisol was higher in non-breeding males, free cortisol was twice as high in breeding males as their corticosteroid binding globulin levels were half as high. In response to the ACTH challenge, testosterone levels in breeding males declined 49% over the first hour and increased 36% over the next hour; in non-breeding males levels showed no change. Free cortisol increased only modestly (26% in breeding males; 23% in non-breeding males). Glucose levels changed similarly in breeding and nonbreeding males, declining for the first 30min and then increasing for the next 60min. Thus, testosterone and components of the stress axis function in a profoundly different manner in male red squirrels than in males of mammals with female-defense mating systems. There are four probable interrelated reasons for these adaptations in male red squirrels: the marginal benefits of each mating, the constraints of mate searching away from their own resource-based territories, energy mobilization in a harsh environment, and a long life span. Copyright © 2017 Elsevier Inc. All rights reserved.

Maternal effects, but no good or compatible genes for sperm competitiveness in Australian crickets.

PubMed

Dowling, Damian K; Nystrand, Magdalena; Simmons, Leigh W

2010-05-01

Explanations for the evolution of polyandry often center on the idea that females garner genetic benefits for their offspring by mating multiply. Furthermore, postcopulatory processes are thought to be fundamental to enabling polyandrous females to screen for genetic quality. Much attention has focused on the potential for polyandrous females to accrue such benefits via a sexy- or good-sperm mechanism, whereby additive variation exists among males in sperm competitiveness. Likewise, attention has focused on an alternative model, in which offspring quality (in this context, the sperm competitiveness of sons) hinges on an interaction between parental haplotypes (genetic compatibility). Sperm competitiveness that is contingent on parental compatibility will exhibit nonadditive genetic variation. We tested these models in the Australian cricket, Teleogryllus oceanicus, using a design that allowed us to partition additive, nonadditive genetic, and parental variance for sperm competitiveness. We found an absence of additive and nonadditive genetic variance in this species, challenging the direct relevance of either model to the evolution of sperm competitiveness in particular, and polyandry in general. Instead, we found maternal effects that were possibly sex-linked or cytoplasmically linked. We also found effects of focal male age on sperm competitiveness, with small increments in age conferring more competitive sperm.

Beyond Symmetry Breaking: Competition and Negative Feedback in GTPase regulation

PubMed Central

Wu, Chi-Fang; Lew, Daniel J.

2013-01-01

Summary Cortical domains are often specified by the local accumulation of active GTPases. Such domains can arise through spontaneous symmetry breaking, suggesting that GTPase accumulation occurs via positive feedback. Here, we focus on recent advances in fungal and plant cell models, where new work suggests that polarity-controlling GTPases develop only one “front” because GTPase clusters engage in a winner-takes-all competition. However, in some circumstances two or more GTPase domains can co-exist, and the basis for the switch from competition to coexistence remains an open question. Polarity GTPases can undergo oscillatory clustering and dispersal, suggesting that these systems contain negative feedback. Negative feedback may prevent polarity clusters from spreading too far, regulate the balance between competition and co-existence, and provide directional flexibility for cells tracking gradients. PMID:23731999

The effect of green supply chain management implementation to marketing performance through company competitiveness (study on paper industry in West Java)

NASA Astrophysics Data System (ADS)

Hijuzaman, O.; Rahayu, A.; Kusnendi

2018-05-01

The purpose of this study was to determine and analyze the effect of direct and indirect implementation of Green Supply-Chain Management (GSCM) on the Performance Marketing and Competitiveness Mediation Paper Company in West Java province. Object This research is the paper company that existed in West Java Province, which amounts to 30 companies as well as a sample of research, while variables studied are Variable Green Supply- Chain Management, Company Competitiveness Variable and Variable of Paper Marketing Industry Performance in West Java Province. The method used SEM with Variance Based or Component Based with Software used is SmartPLS 3.0. On this research are identified that no effect of Competitiveness on Marketing Performance in Paper Companies in West Java Province.

[Policies encouraging price competition in the generic drug market: Lessons from the European experience].

PubMed

Puig-Junoy, Jaume

2010-01-01

To describe alternative policies aimed at encouraging price competition in generic drug markets in countries with strict price regulation, and to present some case studies drawn from the European experience. Systematic literature review of articles and technical reports published after 1999. The shortcomings in consumer price competition observed in some European generic markets, including Spain, may be reduced through three types of public reimbursement or financing reforms: policies aimed at improving the design of current maximum reimbursement level policies; policies aimed at monitoring competitive prices in order to reimburse real acquisition cost to pharmacies; and, more radical and market-oriented policies such as competitive tendering of public drug purchases. The experience of recent reforms adopted in Germany, Belgium, Holland, Norway, and Sweden offers a useful guide for highly price-regulated European countries, such as Spain, currently characterized by limited consumer price competition and the high discounts offered to pharmacy purchases. Direct price regulation and/or the generic reference pricing systems used to reduce generic drug prices in many European countries can be successfully reformed by adopting measures more closely aimed at encouraging consumer price competition in generic drug markets. Copyright 2009 SESPAS. Published by Elsevier Espana. All rights reserved.

Value-modulated oculomotor capture by task-irrelevant stimuli is a consequence of early competition on the saccade map.

PubMed

Pearson, Daniel; Osborn, Raphaella; Whitford, Thomas J; Failing, Michel; Theeuwes, Jan; Le Pelley, Mike E

2016-10-01

Recent research has shown that reward learning can modulate oculomotor and attentional capture by physically salient and task-irrelevant distractor stimuli, even when directing gaze to those stimuli is directly counterproductive to receiving reward. This value-modulated oculomotor capture effect may reflect biased competition in the oculomotor system, such that the relationship between a stimulus feature and reward enhances that feature's representation on an internal priority map. However, it is also possible that this effect is a result of reward reducing the threshold for a saccade to be made to salient items. Here, we demonstrate value-modulated oculomotor capture when two reward-associated distractor stimuli are presented simultaneously in the same search display. The influence of reward on oculomotor capture is found to be most prominent at the shortest saccade latencies. We conclude that the value-modulated oculomotor capture effect is a consequence of biased competition on the saccade priority map and cannot be explained by a general reduction in saccadic threshold.

Rapid micromotor-based naked-eye immunoassay.

PubMed

de Ávila, Berta Esteban-Fernández; Zhao, Mingjiao; Campuzano, Susana; Ricci, Francesco; Pingarrón, José M; Mascini, Marcello; Wang, Joseph

2017-05-15

A dynamic micromotor-based immunoassay, exemplified by cortisol detection, based on the use of tubular micromotors functionalized with a specific antibody is described. The use of antibody-functionalized micromotors offers huge acceleration of both direct and competitive cortisol immunoassays, along with greatly enhanced sensitivity of direct and competitive immunoassays. The dramatically improved speed and sensitivity reflect the greatly increased likelihood of antibody-cortisol contacts and fluid mixing associated with the dynamic movement of these microtube motors and corresponding bubble generation that lead to a highly efficient and rapid recognition process. Rapid naked-eye detection of cortisol in the sample is achieved in connection to use of horseradish peroxidase (HRP) tag and TMB/H 2 O 2 system. Key parameters of the competitive immunoassay (e.g., incubation time and reaction volume) were optimized. This fast visual micromotor-based sensing approach enables "on the move" specific detection of the target cortisol down to 0.1μgmL -1 in just 2min, using ultrasmall (50µL) sample volumes. Copyright © 2017 Elsevier B.V. All rights reserved.

Uses and misuses of statistics: the case of strontium ranelate and the number needed to treat.

PubMed

Pedrazzoni, M; Giusti, A; Pioli, G

2011-09-01

In the last 15 years, several pharmacological agents for the prevention of fractures have been developed and commercialized. Most of them showed to be effective in reducing fracture risk. The enhanced availability of drugs to prevent fractures has generated a fierce competition among pharmaceutical companies to conquer a share of the potential market, often with claims of superiority of a drug over another without direct comparisons. The definitive way to compare different treatments would require randomized head to head trials. These trials are expensive, need large samples and are unlikely to be ever performed. Therefore, it has become a common practice to compare pharmacological agents through observational studies on administrative databases or by the indirect comparison of the results of individual randomised-controlled trials (RCT) and their meta-analyses. These studies may produce evidence of clinical value, complementary to that given by RCT. However, without a proper and complete analysis, they may result in a biased picture of effectiveness and be completely misleading. In this article, we critically disclose how such competition may produce biased and misleading picture of evidence, by reviewing the significance of the number needed to treat, absolute risk reduction and relative risk reduction in relation to vertebral fractures prevention with available drugs.

[Adaptation possibility of chosen aspects of pharmaceutical marketing for realization of promotion in health care].

PubMed

Syrycki, Marek

2002-01-01

Reform of health service in Poland introduced reliable economic bill and elements of competition among its subjects as well. It created a new situation both for doctors and managers of health service. Need of search for rules and ways of competition exists at present among institutions of health care. Certain solutions can be modelled on the example of pharmaceutical companies already present on the market. As an example of such activities, which they can be applied directly in this new situation may serve so called personal sale and related to it case of institutions the best direct contact between the next but more controversial form of marketing activities worth spreading. The use of direct marketing and advertisements carries most problems with itself. This latter should be easier to accept when it selects an important social aim.

An invasive herbivore structures plant competitive dynamics.

PubMed

Wong, Lydia; Grainger, Tess Nahanni; Start, Denon; Gilbert, Benjamin

2017-11-01

Species interactions are central to our understanding of ecological communities, but may change rapidly with the introduction of invasive species. Invasive species can alter species interactions and community dynamics directly by having larger detrimental effects on some species than others, or indirectly by changing the ways in which native species compete among themselves. We tested the direct and indirect effects of an invasive aphid herbivore on a native aphid species and two host milkweed species. The invasive aphid caused a 10-fold decrease in native aphid populations, and a 30% increase in plant mortality (direct effects). The invasive aphid also increased the strength of interspecific competition between the two native plant hosts (indirect effects). By investigating the role that indirect effects play in shaping species interactions in native communities, our study highlights an understudied component of species invasions. © 2017 The Author(s).

Competitive Inhibition Mechanism of Acetylcholinesterase without Catalytic Active Site Interaction: Study on Functionalized C60 Nanoparticles via in Vitro and in Silico Assays.

PubMed

Liu, Yanyan; Yan, Bing; Winkler, David A; Fu, Jianjie; Zhang, Aiqian

2017-06-07

Acetylcholinesterase (AChE) activity regulation by chemical agents or, potentially, nanomaterials is important for both toxicology and pharmacology. Competitive inhibition via direct catalytic active sites (CAS) binding or noncompetitive inhibition through interference with substrate and product entering and exiting has been recognized previously as an AChE-inhibition mechanism for bespoke nanomaterials. The competitive inhibition by peripheral anionic site (PAS) interaction without CAS binding remains unexplored. Here, we proposed and verified the occurrence of a presumed competitive inhibition of AChE without CAS binding for hydrophobically functionalized C 60 nanoparticles (NPs) by employing both experimental and computational methods. The kinetic inhibition analysis distinguished six competitive inhibitors, probably targeting the PAS, from the pristine and hydrophilically modified C 60 NPs. A simple quantitative nanostructure-activity relationship (QNAR) model relating the pocket accessible length of substituent to inhibition capacity was then established to reveal how the geometry of the surface group decides the NP difference in AChE inhibition. Molecular docking identified the PAS as the potential binding site interacting with the NPs via a T-shaped plug-in mode. Specifically, the fullerene core covered the enzyme gorge as a lid through π-π stacking with Tyr72 and Trp286 in the PAS, while the hydrophobic ligands on the fullerene surface inserted into the AChE active site to provide further stability for the complexes. The modeling predicted that inhibition would be severely compromised by Tyr72 and Trp286 deletions, and the subsequent site-directed mutagenesis experiments proved this prediction. Our results demonstrate AChE competitive inhibition of NPs without CAS participation to gain further understanding of both the neurotoxicity and the curative effect of NPs.

A Review of Player Monitoring Approaches in Basketball: Current Trends and Future Directions.

PubMed

Fox, Jordan L; Scanlan, Aaron T; Stanton, Robert

2017-07-01

Fox, JL, Scanlan, AT, and Stanton, R. A review of player monitoring approaches in basketball: current trends and future directions. J Strength Cond Res 31(7): 2021-2029, 2017-Effective monitoring of players in team sports such as basketball requires an understanding of the external demands and internal responses, as they relate to training phases and competition. Monitoring of external demands and internal responses allows coaching staff to determine the dose-response associated with the imposed training load (TL), and subsequently, if players are adequately prepared for competition. This review discusses measures reported in the literature for monitoring the external demands and internal responses of basketball players during training and competition. The external demands of training and competition were primarily monitored using time-motion analysis, with limited use of microtechnology being reported. Internal responses during training were typically measured using hematological markers, heart rate, various TL models, and perceptual responses such as rating of perceived exertion (RPE). Heart rate was the most commonly reported indicator of internal responses during competition with limited reporting of hematological markers or RPE. These findings show a large discrepancy between the reporting of external and internal measures and training and competition demands. Microsensors, however, may be a practical and convenient method of player monitoring in basketball to overcome the limitations associated with current approaches while allowing for external demands and internal responses to be recorded simultaneously. The triaxial accelerometers of microsensors seem well suited for basketball and warrant validation to definitively determine their place in the monitoring of basketball players. Coaching staff should make use of this technology by tracking individual player responses across the annual plan and using real-time monitoring to minimize factors such as fatigue and injury risk.

Multiple mechanisms enable invasive species to suppress native species.

PubMed

Bennett, Alison E; Thomsen, Meredith; Strauss, Sharon Y

2011-07-01

Invasive plants represent a significant threat to ecosystem biodiversity. To decrease the impacts of invasive species, a major scientific undertaking of the last few decades has been aimed at understanding the mechanisms that drive invasive plant success. Most studies and theories have focused on a single mechanism for predicting the success of invasive plants and therefore cannot provide insight as to the relative importance of multiple interactions in predicting invasive species' success. We examine four mechanisms that potentially contribute to the success of invasive velvetgrass Holcus lanatus: direct competition, indirect competition mediated by mammalian herbivores, interference competition via allelopathy, and indirect competition mediated by changes in the soil community. Using a combination of field and greenhouse approaches, we focus on the effects of H. lanatus on a common species in California coastal prairies, Erigeron glaucus, where the invasion is most intense. We found that H. lanatus had the strongest effects on E. glaucus via direct competition, but it also influenced the soil community in ways that feed back to negatively influence E. glaucus and other native species after H. lanatus removal. This approach provided evidence for multiple mechanisms contributing to negative effects of invasive species, and it identified when particular strategies were most likely to be important. These mechanisms can be applied to eradication of H. lanatus and conservation of California coastal prairie systems, and they illustrate the utility of an integrated set of experiments for determining the potential mechanisms of invasive species' success.

The whole relationship between environmental variables and firm performance: competitive advantage and firm resources as mediator variables.

PubMed

López-Gamero, María D; Molina-Azorín, José F; Claver-Cortés, Enrique

2009-07-01

The examination of the possible direct link between environmental protection and firm performance in the literature has generally produced mixed results. The present paper contributes to the literature by using the resource-based view as a mediating process in this relationship. The study specifically tests whether or not the resource-based view of the firm mediates the positive relationships of proactive environmental management and improved environmental performance with competitive advantage, which also has consequences for financial performance. We also check the possible link between the adoption of a pioneering approach and good environmental management practices. Our findings support that early investment timing and intensity in environmental issues impact on the adoption of a proactive environmental management, which in turn helps to improve environmental performance. The findings also show that a firm's resources and competitive advantage act as mediator variables for a positive relationship between environmental protection and financial performance. This contribution is original because the present paper develops a comprehensive whole picture of this path process, which has previously only been partially discussed in the literature. In addition, this study clarifies a relevant point in the literature, namely that the effect of environmental protection on firm performance is not direct and can vary depending on the sector considered. Whereas competitive advantage in relation to costs influences financial performance in the IPPC law sector, the relevant influence in the hotel sector comes from competitive advantage through differentiation.

Significant competitive advantage conferred by meiosis and syngamy in the yeast Saccharomyces cerevisiae.

PubMed Central

Birdsell, J; Wills, C

1996-01-01

The presumed advantages of genetic recombinations are difficult to demonstrate directly. To investigate the effects of recombination and background heterozygosity on competitive ability, we have performed serial-transfer competition experiments between isogenic sexual and asexual strains of the yeast Saccharomyces cerevisiae. The members of these diploid pairs of strains differed only in being heterozygous (sexual) or homozygous (asexual) at the mating type or MAT locus. Competing pairs had either a completely homozygous or a heterozygous genetic background, the latter being heterozygous at many different loci throughout the genome. A round of meiotic recombination (automixis) conferred a large and statistically significant enhancement of competitive ability on sexual strains with a heterozygous genetic background. By contrast, in homozygous background competitions, meiosis decreased the sexual strains' initial relative competitive ability. In all cases, however, the sexual strains outcompeted their isogenic asexual counterparts, whether meiotic recombination had occurred or not. In some genetic backgrounds, this was due in part to an overdominance effect on competitive advantage of heterozygosity at the MAT locus. The advantage of the sexual strains also increased significantly during the course of the homozygous background competitions, particularly when meiosis had occurred. This latter effect either did not occur or was very weak in heterozygous background competitions. Overall, sexual strains with heterozygous genetic backgrounds had a significantly higher initial relative competitive ability than those with homozygous backgrounds. The advantage of mating type heterozygosity in this organism extends far beyond the ability to recombine meiotically. PMID:8570658

Radiographic analysis of vocal tract length and its relation to overall body size in two canid species.

PubMed

Plotsky, K; Rendall, D; Riede, T; Chase, K

2013-09-01

Body size is an important determinant of resource and mate competition in many species. Competition is often mediated by conspicuous vocal displays, which may help to intimidate rivals and attract mates by providing honest cues to signaler size. Fitch proposed that vocal tract resonances (or formants) should provide particularly good, or honest, acoustic cues to signaler size because they are determined by the length of the vocal tract, which in turn, is hypothesized to scale reliably with overall body size. There is some empirical support for this hypothesis, but to date, many of the effects have been either mixed for males compared with females, weaker than expected in one or the other sex, or complicated by sampling issues. In this paper, we undertake a direct test of Fitch's hypothesis in two canid species using large samples that control for age- and sex-related variation. The samples involved radiographic images of 120 Portuguese water dogs Canis lupus familiaris and 121 Russian silver foxes Vulpes vulpes . Direct measurements were made of vocal tract length from X-ray images and compared against independent measures of body size. In adults of both species, and within both sexes, overall vocal tract length was strongly and significantly correlated with body size. Effects were strongest for the oral component of the vocal tract. By contrast, the length of the pharyngeal component was not as consistently related to body size. These outcomes are some of the clearest evidence to date in support of Fitch's hypothesis. At the same time, they highlight the potential for elements of both honest and deceptive body signaling to occur simultaneously via differential acoustic cues provided by the oral versus pharyngeal components of the vocal tract.

Radiographic analysis of vocal tract length and its relation to overall body size in two canid species

PubMed Central

Plotsky, K.; Rendall, D.; Riede, T.; Chase, K.

2013-01-01

Body size is an important determinant of resource and mate competition in many species. Competition is often mediated by conspicuous vocal displays, which may help to intimidate rivals and attract mates by providing honest cues to signaler size. Fitch proposed that vocal tract resonances (or formants) should provide particularly good, or honest, acoustic cues to signaler size because they are determined by the length of the vocal tract, which in turn, is hypothesized to scale reliably with overall body size. There is some empirical support for this hypothesis, but to date, many of the effects have been either mixed for males compared with females, weaker than expected in one or the other sex, or complicated by sampling issues. In this paper, we undertake a direct test of Fitch’s hypothesis in two canid species using large samples that control for age- and sex-related variation. The samples involved radiographic images of 120 Portuguese water dogs Canis lupus familiaris and 121 Russian silver foxes Vulpes vulpes. Direct measurements were made of vocal tract length from X-ray images and compared against independent measures of body size. In adults of both species, and within both sexes, overall vocal tract length was strongly and significantly correlated with body size. Effects were strongest for the oral component of the vocal tract. By contrast, the length of the pharyngeal component was not as consistently related to body size. These outcomes are some of the clearest evidence to date in support of Fitch’s hypothesis. At the same time, they highlight the potential for elements of both honest and deceptive body signaling to occur simultaneously via differential acoustic cues provided by the oral versus pharyngeal components of the vocal tract. PMID:24363497

Inter- and intra-specific competition of duckweed under multiple heavy metal contaminated water.

PubMed

Zhao, Zhao; Shi, Huijuan; Kang, Xianjiang; Liu, Cunqi; Chen, Lingci; Liang, Xiaofei; Jin, Lei

2017-11-01

The influences of intra- and inter-species competition on ecosystems are poorly understood. Lemna aequinoctialis and Spirodela polyrhiza were used to assess the effects of exposure to different concentrations of multiple heavy metals (copper-cadmium-zinc), when the plants were grown in mixed- or mono-culture. Parameters assessed included relative growth rate (RGR), content of chlorophyll, glutathione (GSH), malondialdehyde (MDA), as well as the activity of catalase (CAT), superoxide dismutase (SOD) and peroxidase (POD). Inter-specific competition was affected by metal concentration, with results indicating that inter-specific competition significantly affected duckweed growth and metal uptake in different heavy metal exposure conditions. Inter-specific competition increased growth rate of duckweed under high metal concentrations, although when compared with intra-specific competition, it caused no obvious differences under low metal concentrations. The growth of L. aequinoctialis was further increased in mixed culture when exposed to high metal concentrations, with inter-specific competition increasing the content of cadmium and zinc, while decreasing copper content of L. aequinoctialis compared with under intra-specific conditions. Conversely, inter-specific competition increased the content of copper and cadmium of S. polyrhiza, without causing obvious differences in zinc accumulation under high ambient concentrations. Under high metal conditions, inter-specific competition increased antioxidant enzyme activities in duckweed species, increasing resistance to heavy metals. Results show that inter-specific competition makes duckweed develop mechanisms to increase fitness and survival, such as enhancement of antioxidant enzyme activities, rather than limiting metal uptake when exposed to high concentrations of multiple metals. Copyright © 2017 Elsevier B.V. All rights reserved.

The relationship between competition and quality in procedural cardiac care.

PubMed

Glick, David B; Wroblewski, Kristen; Apfelbaum, Sean; Dauber, Benjamin; Woo, Joyce; Tung, Avery

2015-01-01

Anesthesiologists are frequently involved in efforts to meet perioperative quality metrics. The degree to which hospitals compete on publicly reported quality measures, however, is unclear. We hypothesized that hospitals in more competitive environments would be more likely to compete on quality and thus perform better on such measures. To test our hypothesis, we studied the relationship between competition and quality in hospitals providing procedural cardiac care and participating in a national quality database. For hospitals performing heart valve surgery (HVS) and delivering acute myocardial infarction (AMI) care in the Hospital Compare database, we assessed the degree of intrahospital competition using both geographical radius and federally defined metropolitan statistical area (MSA) to determine the degree of intrahospital competition. For each hospital, we then correlated the degree of competition with quality measure performance, mortality, patient volume, and per-patient Medicare costs for both HVS and AMI. Six hundred fifty-three hospitals met inclusion criteria for HVS and 1898 hospitals for AMI care. We found that for both definitions of competition, hospitals facing greater competition did not demonstrate better quality measure performance for either HVS or AMI. For both diagnoses, competition by number of hospitals correlated positively with cost: partial correlation coefficients = 0.40 (0.42 for MSA) (P < 0.001) for HVS and 0.52 (0.47 for MSA) (P < 0.001) for AMI. An analysis of the Hospital Compare database found that competition among hospitals correlated overall with increased Medicare costs but did not predict better scores on publicly reported quality metrics. Our results suggest that hospitals do not compete meaningfully on publicly reported quality metrics or costs.

Present Circumstances and its Effect of Participation in NHK Robocon/RoboCup Competition for Engineering Education in College of Technology

NASA Astrophysics Data System (ADS)

Sugiura, Touko; Ito, Kazuaki; Watanabe, Masato

The engineering education through making robots which needs various techniques such as construction of mechanism and electric circuit design are very useful for training of the students' creativity and developing the students' personality. Toyota National College of Technology has participate in NHK Robocon competition for sixteen years and Robocup competition for four years as a part of engineering education getting spectacular results in those competitions. This paper discusses the present circumstances and its effect of participation in Robocon/RoboCup competition for the engineering education, based on the students' questionnaire survey. It is described to participate in NHK Robocon competition is very important for enhancing the students' knowledge and experience. Furthermore, the participation in Robocup competition brings better results for student' personality development as compared with participation in only Robocon competition.

Is Nocturnal Foraging in a Tropical Bee an Escape From Interference Competition?

PubMed Central

Kitchen, Shannon M.; Toney, Ryan M.; Ziegler, Christian

2017-01-01

Temporal niche partitioning may result from interference competition if animals shift their activity patterns to avoid aggressive competitors. If doing so also shifts food sources, it is difficult to distinguish the effects of interference and consumptive competition in selecting for temporal niche shift. Bees compete for pollen and nectar from flowers through both interference and consumptive competition, and some species of bees have evolved nocturnality. Here, we use tropical forest canopy towers to observe bees (the night-flying sweat bees Megalopta genalis and M. centralis [Halictidae], honey bees, and stingless bees [Apidae]) visiting flowers of the balsa tree (Ochroma pyramalidae, Malvaceae). Because Ochroma flowers are open in the late afternoon through the night we can test the relative influence of each competition type on temporal nice. Niche shift due to consumptive competition predicts that Megalopta forage when resources are available: from afternoon into the night. Niche shift due to interference competition predicts that Megalopta forage only in the absence of diurnal bees. We found no overlap between diurnal bees and Megalopta in the evening, and only one instance of overlap in the morning, despite the abundance of pollen and nectar in the late afternoon and evening. This supports the hypothesis that Megalopta are avoiding interference competition, but not the hypothesis that they are limited by consumptive competition. We propose that the release from interference competition enables Megalopta to provision cells quickly, and spend most of their time investing in nest defense. Thus, increases in foraging efficiency directly resulting from temporal shifts to escape interference competition may indirectly lead to reduced predation and parasitism. PMID:28931157

A Comparison of Training and Competition Demands in Semiprofessional Male Basketball Players

ERIC Educational Resources Information Center

Fox, Jordan L.; Stanton, Robert; Scanlan, Aaron T.

2018-01-01

Purpose: The purpose of this study was to quantify and compare training and competition demands in basketball. Methods: Fifteen semiprofessional male basketball players wore microsensors during physical conditioning training (PCT), games-based training (GBT), and competition to measure absolute and relative (·min[superscript -1]) PlayerLoad™ (PL)…

Performance-Based Funding as an Instrument of Competition in German Higher Education

ERIC Educational Resources Information Center

Orr, Dominic; Jaeger, Michael; Schwarzenberger, Astrid

2007-01-01

A central theme of approaches to new public management is the emulation of the market through state-induced competition. Basing state funding allocations on comparative performance is one way of setting an incentive for competitive practice amongst universities. Reforms in funding allocation have occurred in Germany at both state and university…

Implementability of Benchmarking (Comparative) Technique in Sports Enterprises (Sample Elazig)

ERIC Educational Resources Information Center

Altungul, Oguzhan; Demirag, Resat

2017-01-01

Increasing competition in domestic and foreign markets in the globalizing world and increasing quality expectations of customers have led enterprises to develop and implement a range of different quality considerations in order to remain competitive or to increase competitive power. One of the most important of these approaches is called…

The competitiveness of medicinal plants in Central Java Indonesia

NASA Astrophysics Data System (ADS)

Riptanti, E. W.; Qonita, R. A.; Fajarningsih, R. U.

2018-03-01

Indonesia hold a potential opportunity to be a pharmaceutical production country. In the other side, Indonesia facing agriculture product and market competition internationally and domestically. Improving competitiveness of specific products are aimed to hit the export market and also to be able to compete with import products in domestic market. Considering Indonesian market opportunity, therefore we perform this study aiming to examine the competitiveness of medicinal plants in Central Java area. The basic method applied in this study was descriptive and data sources are primary and secondary data. Data were analyzed using Revealed Comparative Advantage (RCA) and Trade Specialization Index (TSI) approaches. According to the study, we reveal that medicinal plant commodities in Central Java province have average score 8.52, indicating a strong comparative advantage in global markets, while the commodities appear to have average score of 0.97 at 0 to 1 range, representing a strong competitiveness. Those results are attributed to natural and environmental condition, as well as high demand of global market. This competitiveness will encourage traditional/modern medicinal industries in global market.

The psychology of primate cooperation and competition: a call for realigning research agendas

PubMed Central

Schmelz, Martin; Call, Josep

2016-01-01

Cooperation and competition are two key components of social life. Current research agendas investigating the psychological underpinnings of competition and cooperation in non-human primates are misaligned. The majority of work on competition has been done in the context of theory of mind and deception, while work on cooperation has mostly focused on collaboration and helping. The current impression that theory of mind is not necessarily implicated in cooperative activities and that helping could not be an integral part of competition might therefore be rather misleading. Furthermore, theory of mind research has mainly focused on cognitive aspects like the type of stimuli controlling responses, the nature of representation and how those representations are acquired, while collaboration and helping have focused primarily on motivational aspects like prosociality, common goals and a sense of justice and other-regarding concerns. We present the current state of these two bodies of research paying special attention to how they have developed and diverged over the years. We propose potential directions to realign the research agendas to investigate the psychological underpinnings of cooperation and competition in primates and other animals. PMID:26644603

Indirect Effects of Environmental Change in Resource Competition Models.

PubMed

Kleinhesselink, Andrew R; Adler, Peter B

2015-12-01

Anthropogenic environmental change can affect species directly by altering physiological rates or indirectly by changing competitive outcomes. The unknown strength of competition-mediated indirect effects makes it difficult to predict species abundances in the face of ongoing environmental change. Theory developed with phenomenological competition models shows that indirect effects are weak when coexistence is strongly stabilized, but these models lack a mechanistic link between environmental change and species performance. To extend existing theory, we examined the relationship between coexistence and indirect effects in mechanistic resource competition models. We defined environmental change as a change in resource supply points and quantified the resulting competition-mediated indirect effects on species abundances. We found that the magnitude of indirect effects increases in proportion to niche overlap. However, indirect effects also depend on differences in how competitors respond to the change in resource supply, an insight hidden in nonmechanistic models. Our analysis demonstrates the value of using niche overlap to predict the strength of indirect effects and clarifies the types of indirect effects that global change can have on competing species.

Phylogenetic context determines the role of competition in adaptive radiation

PubMed Central

Tan, Jiaqi; Slattery, Matthew R.; Yang, Xian; Jiang, Lin

2016-01-01

Understanding ecological mechanisms regulating the evolution of biodiversity is of much interest to ecologists and evolutionary biologists. Adaptive radiation constitutes an important evolutionary process that generates biodiversity. Competition has long been thought to influence adaptive radiation, but the directionality of its effect and associated mechanisms remain ambiguous. Here, we report a rigorous experimental test of the role of competition on adaptive radiation using the rapidly evolving bacterium Pseudomonas fluorescens SBW25 interacting with multiple bacterial species that differed in their phylogenetic distance to the diversifying bacterium. We showed that the inhibitive effect of competitors on the adaptive radiation of P. fluorescens decreased as their phylogenetic distance increased. To explain this phylogenetic dependency of adaptive radiation, we linked the phylogenetic distance between P. fluorescens and its competitors to their niche and competitive fitness differences. Competitive fitness differences, which showed weak phylogenetic signal, reduced P. fluorescens abundance and thus diversification, whereas phylogenetically conserved niche differences promoted diversification. These results demonstrate the context dependency of competitive effects on adaptive radiation, and highlight the importance of past evolutionary history for ongoing evolutionary processes. PMID:27335414

Randomized Controlled Trial of Adding Telephone Follow-Up to an Occupational Rehabilitation Program to Increase Work Participation.

PubMed

Hara, Karen Walseth; Bjørngaard, Johan Håkon; Brage, Søren; Borchgrevink, Petter Christian; Halsteinli, Vidar; Stiles, Tore Charles; Johnsen, Roar; Woodhouse, Astrid

2018-06-01

Purpose Transfer from on-site rehabilitation to the participant's daily environment is considered a weak link in the rehabilitation chain. The main objective of this study is to see if adding boosted telephone follow-up directly after completing an occupational rehabilitation program effects work participation. Methods A randomized controlled study included participants with chronic pain, chronic fatigue or common mental disorders on long-term sick leave. After completing 3½ weeks of acceptance and commitment therapy based occupational rehabilitation, participants were randomized to boosted follow-up or a control group before returning to their daily environment. The intervention was delivered over 6 months by on-site RTW coordinators mainly via telephone. Primary outcome was RTW categorized as participation in competitive work ≥1 day per week on average over 8 weeks. Results There were 213 participants of mean age 42 years old. Main diagnoses of sick leave certification were mental disorders (38%) and musculoskeletal disorders (30%). One year after discharge the intervention group had 87% increased odds (OR 1.87, 95% confidence interval 1.06-3.31, p = 0.031), of (re)entry to competitive work ≥1 day per week compared with the controls, with similar positive results for sensitivity analysis of participation half time (≥2.5 days per week). The cost of boosted follow-up was 390.5 EUR per participant. Conclusion Participants receiving boosted RTW follow-up had higher (re)entry to competitive work ≥1 day per week at 1 year when compared to the control group. Adding low-cost boosted follow-up by telephone after completing an occupational rehabilitation program augmented the effect on return-to-work.

Biased Competition in Visual Processing Hierarchies: A Learning Approach Using Multiple Cues.

PubMed

Gepperth, Alexander R T; Rebhan, Sven; Hasler, Stephan; Fritsch, Jannik

2011-03-01

In this contribution, we present a large-scale hierarchical system for object detection fusing bottom-up (signal-driven) processing results with top-down (model or task-driven) attentional modulation. Specifically, we focus on the question of how the autonomous learning of invariant models can be embedded into a performing system and how such models can be used to define object-specific attentional modulation signals. Our system implements bi-directional data flow in a processing hierarchy. The bottom-up data flow proceeds from a preprocessing level to the hypothesis level where object hypotheses created by exhaustive object detection algorithms are represented in a roughly retinotopic way. A competitive selection mechanism is used to determine the most confident hypotheses, which are used on the system level to train multimodal models that link object identity to invariant hypothesis properties. The top-down data flow originates at the system level, where the trained multimodal models are used to obtain space- and feature-based attentional modulation signals, providing biases for the competitive selection process at the hypothesis level. This results in object-specific hypothesis facilitation/suppression in certain image regions which we show to be applicable to different object detection mechanisms. In order to demonstrate the benefits of this approach, we apply the system to the detection of cars in a variety of challenging traffic videos. Evaluating our approach on a publicly available dataset containing approximately 3,500 annotated video images from more than 1 h of driving, we can show strong increases in performance and generalization when compared to object detection in isolation. Furthermore, we compare our results to a late hypothesis rejection approach, showing that early coupling of top-down and bottom-up information is a favorable approach especially when processing resources are constrained.

Primary motor and premotor cortex in implicit sequence learning--evidence for competition between implicit and explicit human motor memory systems.

PubMed

Kantak, Shailesh S; Mummidisetty, Chaithanya K; Stinear, James W

2012-09-01

Implicit and explicit memory systems for motor skills compete with each other during and after motor practice. Primary motor cortex (M1) is known to be engaged during implicit motor learning, while dorsal premotor cortex (PMd) is critical for explicit learning. To elucidate the neural substrates underlying the interaction between implicit and explicit memory systems, adults underwent a randomized crossover experiment of anodal transcranial direct current stimulation (AtDCS) applied over M1, PMd or sham stimulation during implicit motor sequence (serial reaction time task, SRTT) practice. We hypothesized that M1-AtDCS during practice will enhance online performance and offline learning of the implicit motor sequence. In contrast, we also hypothesized that PMd-AtDCS will attenuate performance and retention of the implicit motor sequence. Implicit sequence performance was assessed at baseline, at the end of acquisition (EoA), and 24 h after practice (retention test, RET). M1-AtDCS during practice significantly improved practice performance and supported offline stabilization compared with Sham tDCS. Performance change from EoA to RET revealed that PMd-AtDCS during practice attenuated offline stabilization compared with M1-AtDCS and sham stimulation. The results support the role of M1 in implementing online performance gains and offline stabilization for implicit motor sequence learning. In contrast, enhancing the activity within explicit motor memory network nodes such as the PMd during practice may be detrimental to offline stabilization of the learned implicit motor sequence. These results support the notion of competition between implicit and explicit motor memory systems and identify underlying neural substrates that are engaged in this competition. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

Complexity in African savannas: Direct, indirect, and cascading effects of animal densities, rainfall and vegetation availability

PubMed Central

Leeuwis, Tim; Peel, Mike

2018-01-01

Savanna ecosystems are popular subjects for interaction studies. Multiple studies have been done on the impact of elephants on vegetation, the impact of grass and browse availability on animal densities or on competition between herbivore species. Previous studies showed that elephant densities are frequently negatively correlated with densities of tall trees, and that browse and grass availability are correlated with browser and grazer density respectively. Additionally, a competition effect between browse and grass availability has been reported. These relationships are usually analysed by testing direct relationships between e.g., herbivore densities and food availability, without addressing competition effects or other indirect effects. In this study, multiple interactions in a savanna system have been analysed simultaneously using Partial Least Square-Path Modelling (PLS-PM) using mammal and vegetation data from three different wildlife reserves in southern KwaZulu-Natal. The results showed that the processes that three separate models for the three areas provided the best understanding of the importance of the different interactions. These models suggest that elephants had a negative impact on trees, but also on grass availability. The impact is stronger when elephants are not able to migrate during the dry season. Browsers and grazers were correlated with browse and grass availability, but competition between browse and grass was not detected. This study shows that due to the complexity of the interactions in an ecosystem and differences in environmental factors, these interactions are best studied per area. PLS-PM can be a useful tool for estimating direct, indirect, and cascading effects of changing animal densities in conservation areas. PMID:29768481

Seed germination ecology of Echinochloa glabrescens and its implication for management in rice (Oryza sativa L.).

PubMed

Opeña, Jhoana L; Chauhan, Bhagirath S; Baltazar, Aurora M

2014-01-01

Echinochloa glabrescens is a C4 grass weed that is very competitive with rice when left uncontrolled. The competitive ability of weeds is intensified in direct-seeded rice production systems. A better understanding is needed of factors affecting weed seed germination, which can be used as a component of integrated weed management in direct-seeded rice. This study was conducted to determine the effects of temperature, light, salt and osmotic stress, burial depth, crop residue, time and depth of flooding, and herbicide application on the emergence, survival, and growth of two populations [Nueva Ecija (NE) and Los Baños (IR)] of E. glabrescens. Seeds from both populations germinated at all temperatures. The NE population had a higher germination rate (88%) from light stimulation than did the IR population (34%). The salt concentration and osmotic potential required to inhibit 50% of germination were 313 mM and -0.24 MPa, respectively, for the NE population and 254 mM and -0.33 MPa, respectively, for the IR population. Emergence in the NE population was totally inhibited at 4-cm burial depth in the soil, whereas that of the IR population was inhibited at 8 cm. Compared with zero residue, the addition of 5 t ha(-1) of rice residue reduced emergence in the NE and IR populations by 38% and 9%, respectively. Early flooding (within 2 days after sowing) at 2-cm depth reduced shoot growth by 50% compared with non-flooded conditions. Pretilachlor applied at 0.075 kg ai ha(-1) followed by shallow flooding (2-cm depth) reduced seedling emergence by 94-96% compared with the nontreated flooded treatment. Application of postemergence herbicides at 4-leaf stage provided 85-100% control in both populations. Results suggest that integration of different strategies may enable sustainable management of this weed and of weeds with similar germination responses.

Seed Germination Ecology of Echinochloa glabrescens and Its Implication for Management in Rice (Oryza sativa L.)

PubMed Central

Opeña, Jhoana L.; Chauhan, Bhagirath S.; Baltazar, Aurora M.

2014-01-01

Echinochloa glabrescens is a C4 grass weed that is very competitive with rice when left uncontrolled. The competitive ability of weeds is intensified in direct-seeded rice production systems. A better understanding is needed of factors affecting weed seed germination, which can be used as a component of integrated weed management in direct-seeded rice. This study was conducted to determine the effects of temperature, light, salt and osmotic stress, burial depth, crop residue, time and depth of flooding, and herbicide application on the emergence, survival, and growth of two populations [Nueva Ecija (NE) and Los Baños (IR)] of E. glabrescens. Seeds from both populations germinated at all temperatures. The NE population had a higher germination rate (88%) from light stimulation than did the IR population (34%). The salt concentration and osmotic potential required to inhibit 50% of germination were 313 mM and −0.24 MPa, respectively, for the NE population and 254 mM and −0.33 MPa, respectively, for the IR population. Emergence in the NE population was totally inhibited at 4-cm burial depth in the soil, whereas that of the IR population was inhibited at 8 cm. Compared with zero residue, the addition of 5 t ha−1 of rice residue reduced emergence in the NE and IR populations by 38% and 9%, respectively. Early flooding (within 2 days after sowing) at 2-cm depth reduced shoot growth by 50% compared with non-flooded conditions. Pretilachlor applied at 0.075 kg ai ha−1 followed by shallow flooding (2-cm depth) reduced seedling emergence by 94−96% compared with the nontreated flooded treatment. Application of postemergence herbicides at 4-leaf stage provided 85−100% control in both populations. Results suggest that integration of different strategies may enable sustainable management of this weed and of weeds with similar germination responses. PMID:24642568

Calculating competition in thinned northern hardwoods.

Treesearch

Sharon A. Winsauer; James A. Mattson

1992-01-01

Describes four methods of calculating competition to individual trees and compares their effectiveness in explaining the 3-year growth response of northern hardwoods after various mechanized thinning practices.

Maternal Competition in Women.

PubMed

Linney, Catherine; Korologou-Linden, Laurel; Campbell, Anne

2017-03-01

We examined maternal competition, an unexplored form of competition between women. Given women's high investment in offspring and mothers' key role in shaping their reproductive, social, and cultural success as adults, we might expect to see maternal competition between women as well as mate competition. Predictions about the effect of maternal characteristics (age, relationship status, educational background, number of children, investment in the mothering role) and child variables (age, sex) were drawn from evolutionary theory and sociological research. Mothers of primary school children (in two samples: N = 210 and 169) completed a series of questionnaires. A novel nine-item measure of maternal competitive behavior (MCQ) and two subscales assessing Covert (MCQ-C) and Face-to-Face (MCQ-FF) forms of competition were developed using confirmatory factor analysis. Competitiveness (MCQ score) was predicted by maternal investment, single motherhood, fewer children, and (marginally) child's older age. The effect of single motherhood (but not other predictors) was partially mediated by greater maternal investment. In response to a scenario of their child underperforming relative to their peers, a mother's competitive distress was a positive function of the importance she ascribed to their success and her estimation of her child's ability. Her competitive distress was highly correlated with the distress she attributed to a female friend, hinting at bidirectional dyadic effects. Qualitative responses indicated that nonspecific bragging and boasting about academic achievements were the most common irritants. Although 40% of women were angered or annoyed by such comments, less than 5% endorsed a direct hostile response. Instead, competitive mothers were conversationally shunned and rejected as friends. We suggest that the interdependence of mothers based on reciprocal childcare has supported a culture of egalitarianism that is violated by explicit competitiveness.

Sometimes-Competing Retrieval (SOCR): A Formalization of the Comparator Hypothesis

ERIC Educational Resources Information Center

Stout, Steven C.; Miller, Ralph R.

2007-01-01

Cue competition is one of the most studied phenomena in associative learning. However, a theoretical disagreement has long stood over whether it reflects a learning or performance deficit. The comparator hypothesis, a model of expression of Pavlovian associations, posits that learning is not subject to competition but that performance reflects a…

Future regional transport aircraft market, constraints, and technology stimuli

NASA Technical Reports Server (NTRS)

Harvey, W. Don; Foreman, Brent

1992-01-01

This report provides updated information on the current market and operating environment and identifies interlinking technical possibilities for competitive future commuter-type transport aircraft. The conclusions on the market and operating environment indicate that the regional airlines are moving toward more modern and effective fleets with greater passenger capacity and comfort, reduced noise levels, increased speed, and longer range. This direction leads to a nearly 'seamless' service and continued code-sharing agreements with the major carriers. Whereas the benefits from individual technologies may be small, the overall integration in existing and new aircraft designs can produce improvements in direct operating cost and competitiveness. Production costs are identified as being equally important as pure technical advances.

Para Sport Athletic Identity from Competition to Retirement: A Brief Review and Future Research Directions.

PubMed

Guerrero, Michelle; Martin, Jeffrey

2018-05-01

The primary purpose of this article is to review the literature on para sport athletic identity and provide avenues for future research direction. First, the authors briefly describe the existing quantitative and qualitative research on para sport athletic identity and, thereby, illustrate the complexities para sport athletes experience regarding the way they describe their participation in competitive sport. Next, the authors describe how para sport athletes with acquired permanent disabilities and congenital disabilities face similar, yet unique, identity-related challenges. Finally, the authors argue that future researchers should consider examining para sport athletes' identity through narrative identity. Copyright © 2018 Elsevier Inc. All rights reserved.

Competition for nitrogen between Fagus sylvatica and Acer pseudoplatanus seedlings depends on soil nitrogen availability.

PubMed

Li, Xiuyuan; Rennenberg, Heinz; Simon, Judy

2015-01-01

Competition for nitrogen (N), particularly in resource-limited habitats, might be avoided by different N acquisition strategies of plants. In our study, we investigated whether slow-growing European beech and fast-growing sycamore maple seedlings avoid competition for growth-limiting N by different N uptake patterns and the potential alteration by soil N availability in a microcosm experiment. We quantified growth and biomass indices, (15)N uptake capacity and N pools in the fine roots. Overall, growth indices, N acquisition and N pools in the fine roots were influenced by species-specific competition depending on soil N availability. With inter-specific competition, growth of sycamore maple reduced regardless of soil N supply, whereas beech only showed reduced growth when N was limited. Both species responded to inter-specific competition by alteration of N pools in the fine roots; however, sycamore maple showed a stronger response compared to beech for almost all N pools in roots, except for structural N at low soil N availability. Beech generally preferred organic N acquisition while sycamore maple took up more inorganic N. Furthermore, with inter-specific competition, beech had an enhanced organic N uptake capacity, while in sycamore maple inorganic N uptake capacity was impaired by the presence of beech. Although sycamore maple could tolerate the suboptimal conditions at the cost of reduced growth, our study indicates its reduced competitive ability for N compared to beech.

Kinetics of badminton lunges in four directions.

PubMed

Hong, Youlian; Wang, Shao Jun; Lam, Wing Kai; Cheung, Jason Tak Man

2014-02-01

The lunge is the most fundamental skill in badminton competitions. Fifteen university-level male badminton players performed lunge maneuvers in four directions, namely, right-forward, left-forward, right-backward, and left-backward, while wearing two different brands of badminton shoes. The test compared the kinetics of badminton shoes in performing typical lunge maneuvers. A force plate and an insole measurement system measured the ground reaction forces and plantar pressures. These measurements were compared across all lunge maneuvers. The left-forward lunge generated significantly higher first vertical impact force (2.34 ± 0.52 BW) than that of the right-backward (2.06 ± 0.60 BW) and left-backward lunges (1.78 ± 0.44 BW); higher second vertical impact force (2.44 ± 0.51 BW) than that of the left-backward lunge (2.07 ± 0.38 BW); and higher maximum anterior-posterior shear force (1.48 ± 0.36 BW) than that of the left-backward lunge (1.18 ± 0.38 BW). Compared with other lunge directions, the left-forward lunge showed higher mean maximum vertical impact anterior-posterior shear forces and their respective maximum loading rates, and the plantar pressure at the total foot and heel regions. Therefore, the left-forward lunge is a critical maneuver for badminton biomechanics and related footwear research because of the high loading magnitude generated during heel impact.

Rise and fall of competitiveness in individualistic and collectivistic societies.

PubMed

Leibbrandt, Andreas; Gneezy, Uri; List, John A

2013-06-04

Competitiveness pervades life: plants compete for sunlight and water, animals for territory and food, and humans for mates and income. Herein we investigate human competitiveness with a natural experiment and a set of behavioral experiments. We compare competitiveness in traditional fishing societies where local natural forces determine whether fishermen work in isolation or in collectives. We find sharp evidence that fishermen from individualistic societies are far more competitive than fishermen from collectivistic societies, and that this difference emerges with work experience. These findings suggest that humans can evolve traits to specific needs, support the idea that socio-ecological factors play a decisive role for individual competitiveness, and provide evidence how individualistic and collectivistic societies shape economic behavior.

Species interactions and response time to climate change: ice-cover and terrestrial run-off shaping Arctic char and brown trout competitive asymmetries

NASA Astrophysics Data System (ADS)

Finstad, A. G.; Palm Helland, I.; Jonsson, B.; Forseth, T.; Foldvik, A.; Hessen, D. O.; Hendrichsen, D. K.; Berg, O. K.; Ulvan, E.; Ugedal, O.

2011-12-01

There has been a growing recognition that single species responses to climate change often mainly are driven by interaction with other organisms and single species studies therefore not are sufficient to recognize and project ecological climate change impacts. Here, we study how performance, relative abundance and the distribution of two common Arctic and sub-Arctic freshwater fishes (brown trout and Arctic char) are driven by competitive interactions. The interactions are modified both by direct climatic effects on temperature and ice-cover, and indirectly through climate forcing of terrestrial vegetation pattern and associated carbon and nutrient run-off. We first use laboratory studies to show that Arctic char, which is the world's most northernmost distributed freshwater fish, outperform trout under low light levels and also have comparable higher growth efficiency. Corresponding to this, a combination of time series and time-for-space analyses show that ice-cover duration and carbon and nutrient load mediated by catchment vegetation properties strongly affected the outcome of the competition and likely drive the species distribution pattern through competitive exclusion. In brief, while shorter ice-cover period and decreased carbon load favored brown trout, increased ice-cover period and increased carbon load favored Arctic char. Length of ice-covered period and export of allochthonous material from catchments are major, but contrasting, climatic drivers of competitive interaction between these two freshwater lake top-predators. While projected climate change lead to decreased ice-cover, corresponding increase in forest and shrub cover amplify carbon and nutrient run-off. Although a likely outcome of future Arctic and sub-arctic climate scenarios are retractions of the Arctic char distribution area caused by competitive exclusion, the main drivers will act on different time scales. While ice-cover will change instantaneously with increasing temperature, changes in catchment vegetation, such as forest-line or shrub advancement affecting carbon and nutrient transport into lakes, act on considerably longer time-scales. This study therefore emphasizes the recurring challenge for ecological climate change studies related to species interactions within and across ecosystem compartments and the response time of ecosystems.

[Effects of neighbor competition on growth, fine root morphology and distribution of Schima superba and Cunninghamia lanceolata in different nutrient environments].

PubMed

Yao, Jia Bao; Chu, Xiu Li; Zhou, Zhi Chun; Tong, Jian She; Wang, Hui; Yu, Jia Zhong

2017-05-18

Taking Schima superba and Cunninghamia lanceolata as test materials, a pot experiment was conducted to simulate the heterogeneous and homogeneous forest soil nutrient environments, and design three planting modes including single plant, two-strain pure plant and two-strain mixed ones to reason the promotion in mixed S. superba and C. lanceolata plantation and the competitive advantage of S. superba. Results showed that compared with the homogeneous nutrient environment, both S. superba and C. lanceolata had the higher seedling height and dry matter accumulation, when mixed in the heterogeneous nutrient environment, S. superba displayed the obviously competitive advantage, which related to its root plasticity. The fine root of S. superba mixed in each diameter class showed a lot of hyperplasia, and the root total length, surface area and volume of which were 80%-180% higher than that of C. lanceolata. S. superba took the advantage of the compensatory growth strategy of vertical direction in fine roots, namely, they still multiplied to gain greater competitive advantage in low nutrient patches, besides occupying eutrophic surface. The different soil colonization and niche differentiation in fine root of S. superba and C. lanceolata alleviated the strong competition for nutrients of the roots of the two species, and improved the mixed-plantation production. Pure plantation of S. superba harvested the lower yield, which due to the root self-recognition inhibited the growth of root system. Fine roots staggered and evenly distributed on the space might be a reason for stable structure of pure S. superba plantation. So, it was recommended that block surface layer soil preparation and fertilization are used to improve the soil nutrient distribution, and the mixed plantation is constructed to promote the growth of S. superba and C. lanceolata, at the same time, the stand density is regulated to promote tree growth for the pure artificial S. superba plantation which had already been built.

Influence of training and competitive sessions on peripheral β-endorphin levels in training show jumping horses.

PubMed

Cravana, Cristina; Medica, P; Ragonese, G; Fazio, E

2017-01-01

To investigate the effects of training sessions on circulating β-endorphin changes in sport horses before and after competition and to ascertain whether competition would affect this response. A total of 24 trained jumping horses were randomly assigned to one of two training groups: Group A (competing) and Group B (not competing). To determined plasma β-endorphin concentrations, two pre- and post-competition training weeks at aerobic workout and two competitive show jumping event days at anaerobic workout were measured before, 5 and 30 min after exercise. Exercise intensity is described using lactate concentrations and heart rate. The circuit design, intensity, and duration of training sessions were the same for both groups. In Group A, one-way analysis of variance for repeated measures (RM-ANOVA) showed significant effects of exercise on β-endorphin changes (F=14.41; p<0.001), only in the post-competition training sessions, while in Group B showed no significant effects. Two-way RM-ANOVA showed, after post-competition training sessions, a significant difference between Group A and Group B (F=6.235; p=0.023), with higher β-endorphin changes in Group A, compared to Group B. During the competitive show jumping sessions, one-way RM ANOVA showed significant effects of exercise on β-endorphin changes (F=51.10; p<0.001). The statistical analysis, in Group A, showed a significant difference between post-competition training and competitive exercise (F=6.32; p=0.024) with higher β-endorphin values in competitive sessions compared to those of post-competition training. Lactate concentrations seem to be the main factors being correlated with the raise of β-endorphin during anaerobic exercise of competitive events. Exercise of low intensity, as well as that one of training sessions, does not appear to stimulate a significant increased release of β-endorphin and it may depend on the duration of the exercise program. Moreover, the responses during exercise in the course of post-competition training sessions seem to be significantly different from those the pre-competition training. These data show that the preliminary competitive stress induced additional significant changes of β-endorphin pattern. It would reflect the need of a long-lasting modulation of fatigue and pain perception related to the effect of an additional physical and mental effort for the consecutive competitive and training sessions.

Prospects for regulated competition in the health care system: what can China learn from Russia's experience?

PubMed

Xu, Weiwei; Sheiman, Igor; van de Ven, Wynand P M M; Zhang, Wei

2011-05-01

As China explores new directions to reform its health care system, regulated competition among both insurers and providers of care might be one potential model. The Russian Federation in 1993 implemented legislation intended to stimulate such regulated competition in the health care sector. The subsequent progress and lessons learned over these 17 years can shed light on and inform the future evolution of the Chinese system. In this paper, we list the necessary pre-conditions for reaping the benefits of regulated competition in the health care sector. We indicate to what extent these conditions are being fulfilled in the post-reform Russian and current Chinese health care systems. We draw lessons from the Russian experience for the Chinese health care system, which shares a similar economic and political background with the pre-reform Russian health care system in terms of the starting point of the reform, and analyse the prospects for regulated competition in China.

Robotics Programming Competition Spheres, Russian Part

NASA Astrophysics Data System (ADS)

Sadovski, Andrei; Kukushkina, Natalia; Biryukova, Natalia

2016-07-01

Spheres" such name was done to Russian part of the Zero Robotics project which is a student competition devoted to programming of SPHERES (SPHERES - Synchronized Position Hold Engage and Reorient Experimental Satellites are the experimental robotics devices which are capable of rotation and translation in all directions, http://ssl.mit.edu/spheres/), which perform different operations on the board of International Space Station. Competition takes place online on http://zerorobotics.mit.edu. The main goal is to develop a program for SPHERES to solve an annual challenge. The end of the tournament is the real competition in microgravity on the board of ISS with a live broadcast. The Russian part of the tournament has only two years history but the problems, organization and specific are useful for the other educational projects especially for the international ones. We introduce the history of the competition, its scientific and educational goals in Russia and describe the participation of Russian teams in 2014 and 2015 tournaments. Also we discuss the organizational problems.

Prediction of competitive diffusion on complex networks

NASA Astrophysics Data System (ADS)

Zhao, Jiuhua; Liu, Qipeng; Wang, Lin; Wang, Xiaofan

2018-10-01

In this paper, we study the prediction problem of diffusion process on complex networks in competitive circumstances. With this problem solved, the competitors could timely intervene the diffusion process if needed such that an expected outcome might be obtained. We consider a model with two groups of competitors spreading opposite opinions on a network. A prediction method based on the mutual influences among the agents is proposed, called Influence Matrix (IM for short), and simulations on real-world networks show that the proposed IM method has quite high accuracy on predicting both the preference of any normal agent and the final competition result. For comparison purpose, classic centrality measures are also used to predict the competition result. It is shown that PageRank, Degree, Katz Centrality, and the IM method are suitable for predicting the competition result. More precisely, in undirected networks, the IM method performs better than these centrality measures when the competing group contains more than one agent; in directed networks, the IM method performs only second to PageRank.

Getting the product right: how competition policy can improve health care markets.

PubMed

Sage, William M

2014-06-01

As hospital, physician, and health insurance markets consolidate and change in response to health care reform, some commentators have called for vigorous enforcement of the federal antitrust laws to prevent the acquisition and exercise of market power. In health care, however, stricter antitrust enforcement will benefit consumers only if it accounts for the competitive distortions caused by the sector's long history of government regulation. This article directs policy makers to a neglected dimension of health care competition that has been altered by regulation: the product. Competition may have failed to significantly lower costs, increase access, or improve quality in health care because we have been buying and selling the wrong things. Competition policy makers-meaning both antitrust enforcers and regulators-should force the health care industry to define and market products that can be assembled and warranted to consumers while keeping emerging sectors such as mHealth free from overregulation, wasteful subsidy, and appropriation by established insurer and provider interests. Project HOPE—The People-to-People Health Foundation, Inc.

A Comparative Analysis of the Use of Competitive Intelligence Tools in a Multinational Corporation

ERIC Educational Resources Information Center

Breese-Vitelli, Jennifer

2011-01-01

With the growth of the global economy, organizations large and small are increasingly recognizing that competitive intelligence (CI) is essential to compete in industry. Competitive intelligence is used to gain an advantage in commerce and is useful for analyzing a company's strategic industry position. To remain current and profitable,…

The Effects of Competitive vs. Cooperative Structures on Subsequent Productivity in Boys with Psychosocial Disorders.

ERIC Educational Resources Information Center

Nelson, David L.; Peterson, Cindee Q.

1991-01-01

A study compared three subject groups structured for competition to three subject groups structured for cooperation. Thirty-six 8- to 17-year-old males residing in a treatment center for nonpsychotic psychosocial disorders participated in competitive and cooperative dice games. Results did not support the hypothesis that a cooperative experience…

Transactional Influences of Infants' Orienting Ability and Maternal Cooperation on Competition in Three-Year-Old Children.

ERIC Educational Resources Information Center

Lutkenhaus, Paul; And Others

1985-01-01

Describes how three-year-olds regulate their effort during competition and compares their facial expressions after failure and success, demonstrating the operation of a display rule in competition. Explores the cross-situational stability of subjects' regulation of behavior, as well as the relationship between factors influencing mother-child…

The Development and Implementation of a Dental School Strategic Plan.

ERIC Educational Resources Information Center

Moreland, Ernest F.; And Others

1990-01-01

The University of Maryland Dental School began a comprehensive external and internal analysis of dentistry and dental education. Three analysis groups were established to review the external environment, the competitive environment, and institutional strengths and weaknesses. A strategic directions group identified directions and created a…

Direct Lending Works.

ERIC Educational Resources Information Center

Riley, Richard W.

1997-01-01

In its third year, direct lending is working well for college students and administration. It is a simpler, faster, more efficient way of getting loan funds to students that cuts out financial middlemen. It helps students manage their finances better when repaying loans, promotes competition, stimulates program innovation, leads to greater…

Response to competition of bulbous geophyte Allium oleraceum differing in ploidy level.

PubMed

Fialová, M; Duchoslav, M

2014-01-01

Experimental studies that explore the possible causes of ploidy distributions and niche differentiation are rare. Increased competitive ability may be advantageous for survival in dense vegetation and may strongly affect local and regional abundances of cytotypes and potentially contribute to invasion success. We compared survival, growth and reproduction of plants originating from bulbils of three cytotypes (2n = 4x, 5x, 6x) of Allium oleraceum growing with and without a competitor (Arrhenatherum elatius). There was a strong negative effect of competition but no effect of ploidy or ploidy × competition on survivorship, height and total dry mass of A. oleraceum, i.e. no support for different competitive abilities of the ploidy levels. However, slightly different responses of populations to competition treatments within all cytotypes suggest differentiation within cytotypes. Under competition, plant survivorship was low, surviving plants were small, had low dry mass and produced neither sexual nor asexual propagules. Without competition, plant survivorship was high, and cytotypes differed in three traits after 2 year's growth: dry mass of flowers, number of flowers and ratio of the dry mass of sexual to asexual propagules all decreased with increasing ploidy level. We additionally tested tetra- and pentaploids as to whether plants originating from different types of propagule (bulbils, seeds) differ in survivorship, growth and reproduction when growing with and without a competitor. Plants originating from bulbils had higher survivorship, were more robust, flowered earlier and produced more propagules when compared to plants originating from seeds and grown without competition. Under competition, differences in performance between plants originating from seeds and bulbils mostly disappeared, with higher survivorship only for plants originating from bulbils. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

Effects of competition on students' self-efficacy in vicarious learning.

PubMed

Chan, Joanne C Y; Lam, Shui-fong

2008-03-01

Vicarious learning is one of the fundamental sources of self-efficacy that is frequently employed in educational settings. However, little research has investigated the effects of competition on students' writing self-efficacy when they engage in vicarious learning. This study compared the effects of competitive and non-competitive classrooms on students' writing self-efficacy when they engaged in vicarious learning. The participants were 71 grade 7 students in Hong Kong. Using prior writing performance for stratified random sampling, students were assigned either to a competitive or a non-competitive classroom. Students learned how to compose similes and metaphors in Chinese. In the competitive classroom, students' self-efficacy decreased when they engaged in vicarious learning. In the non-competitive classroom, students' self-efficacy did not show a significant change when they engaged in vicarious learning. The findings suggested that when students engaged in vicarious learning in a competitive classroom, their self-efficacy might be threatened. Implications for efforts to design constructive context for vicarious learning are discussed.

The capture of heritable variation for genetic quality through social competition.

PubMed

Wolf, Jason B; Harris, W Edwin; Royle, Nick J

2008-09-01

In theory, females of many species choose mates based on traits that are indicators of male genetic quality. A fundamental question in evolutionary biology is why genetic variation for such indicator traits persists despite strong persistent selection imposed by female preference, which is known as the lek paradox. One potential solution to the lek paradox suggests that the traits that are targets of mate choice should evolve condition-dependent expression and that condition should have a large genetic variance. Condition is expected to exhibit high genetic variance because it is affected by a large number of physiological processes and hence, condition-dependent traits should 'capture' variation contributed by a large number of loci. We suggest that a potentially important cause of variation in condition is competition for limited resources. Here, we discuss a pair of models to analyze the evolutionary genetics of traits affected by success in social competition for resources. We show that competition can contribute to genetic variation of 'competition-dependent' traits that have fundamentally different evolutionary properties than other sources of variation. Competition dependence can make traits honest indicators of genetic quality by revealing the relative competitive ability of males, can provide a component of heritable variation that does not contribute to trait evolution, and can help maintain heritable variation under directional selection. Here we provide a general introduction to the concept of competition dependence and briefly introduce two models to demonstrate the potential evolutionary consequences of competition-dependent trait expression.

Pollinator Competition as a Driver of Floral Divergence: An Experimental Test.

PubMed

Temeles, Ethan J; Newman, Julia T; Newman, Jennifer H; Cho, Se Yeon; Mazzotta, Alexandra R; Kress, W John

2016-01-01

Optimal foraging models of floral divergence predict that competition between two different types of pollinators will result in partitioning, increased assortative mating, and divergence of two floral phenotypes. We tested these predictions in a tropical plant-pollinator system using sexes of purple-throated carib hummingbirds (Anthracothorax jugularis) as the pollinators, red and yellow inflorescence morphs of Heliconia caribaea as the plants, and fluorescent dyes as pollen analogs in an enclosed outdoor garden. When foraging alone, males exhibited a significant preference for the yellow morph of H. caribaea, whereas females exhibited no preference. In competition, males maintained their preference for the yellow morph and through aggression caused females to over-visit the red morph, resulting in resource partitioning. Competition significantly increased within-morph dye transfer (assortative mating) relative to non-competitive environments. Competition and partitioning of color morphs by sexes of purple-throated caribs also resulted in selection for floral divergence as measured by dye deposition on stigmas. Red and yellow morphs did not differ significantly in dye deposition in the competition trials, but differences in dye deposition and preferences for morphs when sexes of purple-throated caribs foraged alone implied fixation of one or the other color morph in the absence of competition. Competition also resulted in selection for divergence in corolla length, with the red morph experiencing directional selection for longer corollas and the yellow morph experiencing stabilizing selection on corolla length. Our results thus support predictions of foraging models of floral divergence and indicate that pollinator competition is a viable mechanism for divergence in floral traits of plants.

Pollinator Competition as a Driver of Floral Divergence: An Experimental Test

PubMed Central

Temeles, Ethan J.; Newman, Julia T.; Newman, Jennifer H.; Cho, Se Yeon; Mazzotta, Alexandra R.; Kress, W. John

2016-01-01

Optimal foraging models of floral divergence predict that competition between two different types of pollinators will result in partitioning, increased assortative mating, and divergence of two floral phenotypes. We tested these predictions in a tropical plant-pollinator system using sexes of purple-throated carib hummingbirds (Anthracothorax jugularis) as the pollinators, red and yellow inflorescence morphs of Heliconia caribaea as the plants, and fluorescent dyes as pollen analogs in an enclosed outdoor garden. When foraging alone, males exhibited a significant preference for the yellow morph of H. caribaea, whereas females exhibited no preference. In competition, males maintained their preference for the yellow morph and through aggression caused females to over-visit the red morph, resulting in resource partitioning. Competition significantly increased within-morph dye transfer (assortative mating) relative to non-competitive environments. Competition and partitioning of color morphs by sexes of purple-throated caribs also resulted in selection for floral divergence as measured by dye deposition on stigmas. Red and yellow morphs did not differ significantly in dye deposition in the competition trials, but differences in dye deposition and preferences for morphs when sexes of purple-throated caribs foraged alone implied fixation of one or the other color morph in the absence of competition. Competition also resulted in selection for divergence in corolla length, with the red morph experiencing directional selection for longer corollas and the yellow morph experiencing stabilizing selection on corolla length. Our results thus support predictions of foraging models of floral divergence and indicate that pollinator competition is a viable mechanism for divergence in floral traits of plants. PMID:26814810

Seal dynamics on the Swedish west coast: Scenarios of competition as Baltic grey seal intrude on harbour seal territory

NASA Astrophysics Data System (ADS)

Svensson, Carl Johan

2012-07-01

The Kattegat-Skagerrak region on the Swedish west coast is home to an abundant harbour seal population (Phoca vitulina) and a small scattered grey seal population (Halichoerus grypus). In addition, grey seal from the growing population in the Baltic Sea frequently migrate into the Kattegat-Skagerrak. Harbour seals on the west coast of Sweden show relatively high population growth (approximately 9%) compared to the Baltic grey seal in ice-free habitats (approximately 6%), which, in theory, makes harbour seal the stronger competitor of the two in this region. However, incidents of disease in harbour seals that lower population growth are becoming more frequent. These epidemics are primarily caused by the Phocine Distemper Virus (PDV), and may reduce population size with up to 70%. This study models the average development under potential scenarios of competing harbour- and Baltic grey seal populations using Leslie matrices and the Lotka-Volterra model of inter-specific competition. The model is parameterised with previously published data, and resource overlap is incorporated through density dependent pup survival. Using numerical methods short- and long-term abundances are simulated under weak, moderate and strong competition and for different frequencies of PDV epidemics. Results show that the harbour seals are resilient to competition while exerting a negative effect on grey seal abundance under moderate to strong competition. Hence Baltic grey seal benefit from weaker levels of competition. Under moderate and strong competition grey seal abundance is a direct function of the PDV frequency as this reduces the competitive strength of harbour seals. Theoretically this means that higher frequencies of PDV or other pathogens epidemics could facilitate an expansion of Baltic grey seal into Kattegat-Skagerrak. Independent of interaction strength and frequency of epidemics the projected changes to abundances are slow (50-100 years), and even in exceedingly stable populations very long time-series of population size estimates are necessary to determine interaction strength. From a management perspective, a more permanent grey seal population in Kattegat-Skagerrak is likely to increase the predation pressure on overfished regional cod populations, and also lead to higher prevalence of the cod parasite Pseudoterranova decipiens, which uses grey seal as end host. From a population ecology perspective, abundant Baltic grey seal in this region would facilitate the mixing of grey seals from the North Atlantic and the Baltic Sea, with unknown implications for the genetically divergent Baltic population.

State University System Graduation and Retention Rates Are Nationally Competitive. Information Brief

ERIC Educational Resources Information Center

Board of Governors, State University System of Florida, 2011

2011-01-01

The State University System of Florida six-year graduation rate and second-year retention rate are strong compared to the ten largest public university systems. Graduation rates for the System's minority students are also competitive, with rates for non-Hispanic Black students and Hispanic students ranked in the top 10 when compared to all…

Government Approaches to Foster Competitive Intelligence Practice in SMEs: A Comparative Study of Eight Governments.

ERIC Educational Resources Information Center

Bergeron, Pierrette

2000-01-01

Presents results from a study examining approaches developed by seven governments to foster competitive intelligence practice in SMEs (small and medium enterprises) and compares them with the approach taken by the government of Quebec. Suggests a need for a better understanding of information needs and uses in SMEs. (Contains 22 references.)…

Simulated Warming Differentially Affects the Growth and Competitive Ability of Centaurea maculosa Populations from Home and Introduced Ranges

PubMed Central

He, Wei-Ming; Li, Jing-Ji; Peng, Pei-Hao

2012-01-01

Climate warming may drive invasions by exotic plants, thereby raising concerns over the risks of invasive plants. However, little is known about how climate warming influences the growth and competitive ability of exotic plants from their home and introduced ranges. We conducted a common garden experiment with an invasive plant Centaurea maculosa and a native plant Poa pratensis, in which a mixture of sand and vermiculite was used as a neutral medium, and contrasted the total biomass, competitive effects, and competitive responses of C. maculosa populations from Europe (home range) and North America (introduced range) under two different temperatures. The warming-induced inhibitory effects on the growth of C. maculosa alone were stronger in Europe than in North America. The competitive ability of C. maculosa plants from North America was greater than that of plants from Europe under the ambient condition whereas this competitive ability followed the opposite direction under the warming condition, suggesting that warming may enable European C. maculosa to be more invasive. Across two continents, warming treatment increased the competitive advantage instead of the growth advantage of C. maculosa, suggesting that climate warming may facilitate C. maculosa invasions through altering competitive outcomes between C. maculosa and its neighbors. Additionally, the growth response of C. maculosa to warming could predict its ability to avoid being suppressed by its neighbors. PMID:22303485

Simulated warming differentially affects the growth and competitive ability of Centaurea maculosa populations from home and introduced ranges.

PubMed

He, Wei-Ming; Li, Jing-Ji; Peng, Pei-Hao

2012-01-01

Climate warming may drive invasions by exotic plants, thereby raising concerns over the risks of invasive plants. However, little is known about how climate warming influences the growth and competitive ability of exotic plants from their home and introduced ranges. We conducted a common garden experiment with an invasive plant Centaurea maculosa and a native plant Poa pratensis, in which a mixture of sand and vermiculite was used as a neutral medium, and contrasted the total biomass, competitive effects, and competitive responses of C. maculosa populations from Europe (home range) and North America (introduced range) under two different temperatures. The warming-induced inhibitory effects on the growth of C. maculosa alone were stronger in Europe than in North America. The competitive ability of C. maculosa plants from North America was greater than that of plants from Europe under the ambient condition whereas this competitive ability followed the opposite direction under the warming condition, suggesting that warming may enable European C. maculosa to be more invasive. Across two continents, warming treatment increased the competitive advantage instead of the growth advantage of C. maculosa, suggesting that climate warming may facilitate C. maculosa invasions through altering competitive outcomes between C. maculosa and its neighbors. Additionally, the growth response of C. maculosa to warming could predict its ability to avoid being suppressed by its neighbors.

Apparent competition with an invasive plant hastens the extinction of an endangered lupine.

PubMed

Dangremond, Emily M; Pardini, Eleanor A; Knight, Tiffany M

2010-08-01

Invasive plants may compete with native plants by increasing the pressure of native consumers, a mechanism known as "apparent competition." Apparent competition can be as strong as or stronger than direct competition, but the role of apparent competition has rarely been examined in biological invasions. We used four years of demographic data and seed-removal experiments to determine if introduced grasses caused elevated levels of seed consumption on native plant species in a coastal dune system in California, USA. We show that the endangered, coastal dune plant Lupinus tidestromii experiences high levels of pre-dispersal seed consumption by the native rodent Peromyscus maniculatus due to its proximity to the invasive grass, Ammophila arenaria. We use stage-structured, stochastic population models to project that two of three study populations will decline toward extinction under ambient levels of consumption. For one of these declining populations, a relatively small decrease in consumption pressure should allow for persistence. We show that apparent competition with an invasive species significantly decreases the population growth rate and persistence of a native species. We expect that apparent competition is an important mechanism in other ecosystems because invasive plants often change habitat structure and plant-consumer interactions. Possible implications of the apparent-competition mechanism include selective extinction of species preferred by seed consumers in the presence of an invasive species and biological homogenization of communities toward non-preferred native plant species.

Study on competitive adsorption mechanism among oxyacid-type heavy metals in co-existing system: Removal of aqueous As(V), Cr(III) and As(III) using magnetic iron oxide nanoparticles (MIONPs) as adsorbents

NASA Astrophysics Data System (ADS)

Lin, Sen; Lian, Cheng; Xu, Meng; Zhang, Wei; Liu, Lili; Lin, Kuangfei

2017-11-01

The adsorption and co-adsorption of As(V), Cr(VI) and As(III) onto the magnetic iron oxide nanoparticles (MIONPs) surface were investigated comprehensively to clarify the competitive processes. The results reflected that the MIONPs had remarkable preferential adsorption to As(V) compared with Cr(VI) and As(III). And it was determined, relying on the analysis of heavy metals variations on the MIONPs surface at different co-adsorption stages using FTIR and XPS, that the inner-sphere complexation made vital contribution to the preferential adsorption for As(V), corresponding with the replacement experiments where As(V) could grab extensively active sites on the MIONPs pre-occupied by As(III) or Cr(V) uniaxially. The desorption processes displayed that the strongest affinity between the MIONPs and As(V) where As(III) and Cr(VI) were more inclined to wash out. It is wish to provide a helpful direction with this study for the wastewater treatment involving multiple oxyacid-type heavy metals using MIONPs as adsorbents.

Is Nocturnal Foraging in a Tropical Bee an Escape From Interference Competition?

PubMed

Smith, Adam R; Kitchen, Shannon M; Toney, Ryan M; Ziegler, Christian

2017-01-01

Temporal niche partitioning may result from interference competition if animals shift their activity patterns to avoid aggressive competitors. If doing so also shifts food sources, it is difficult to distinguish the effects of interference and consumptive competition in selecting for temporal niche shift. Bees compete for pollen and nectar from flowers through both interference and consumptive competition, and some species of bees have evolved nocturnality. Here, we use tropical forest canopy towers to observe bees (the night-flying sweat bees Megalopta genalis and M. centralis [Halictidae], honey bees, and stingless bees [Apidae]) visiting flowers of the balsa tree (Ochroma pyramalidae, Malvaceae). Because Ochroma flowers are open in the late afternoon through the night we can test the relative influence of each competition type on temporal nice. Niche shift due to consumptive competition predicts that Megalopta forage when resources are available: from afternoon into the night. Niche shift due to interference competition predicts that Megalopta forage only in the absence of diurnal bees. We found no overlap between diurnal bees and Megalopta in the evening, and only one instance of overlap in the morning, despite the abundance of pollen and nectar in the late afternoon and evening. This supports the hypothesis that Megalopta are avoiding interference competition, but not the hypothesis that they are limited by consumptive competition. We propose that the release from interference competition enables Megalopta to provision cells quickly, and spend most of their time investing in nest defense. Thus, increases in foraging efficiency directly resulting from temporal shifts to escape interference competition may indirectly lead to reduced predation and parasitism. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

Competitive Procurement of Electrical Power.

DTIC Science & Technology

1987-12-01

clear authority to form them was granted by the Public Utility Regulatory Policies Act of 1978 ( PURPA ). To understand PURPA . it is necessary to...Regulatory Policies Act of 1978, ( PURPA ); and 2. Chapter 647, 26 Statute 209 (1980), as amended, the Sherman Act. More than any others, these statutes and...Number 5 further directs that competition will be initiated when it is "most advanta- geous to the Government."’ 6 When Congress passed PURPA on 9

Rise and fall of competitiveness in individualistic and collectivistic societies

PubMed Central

Leibbrandt, Andreas; Gneezy, Uri; List, John A.

2013-01-01

Competitiveness pervades life: plants compete for sunlight and water, animals for territory and food, and humans for mates and income. Herein we investigate human competitiveness with a natural experiment and a set of behavioral experiments. We compare competitiveness in traditional fishing societies where local natural forces determine whether fishermen work in isolation or in collectives. We find sharp evidence that fishermen from individualistic societies are far more competitive than fishermen from collectivistic societies, and that this difference emerges with work experience. These findings suggest that humans can evolve traits to specific needs, support the idea that socio-ecological factors play a decisive role for individual competitiveness, and provide evidence how individualistic and collectivistic societies shape economic behavior. PMID:23696669

Competition between the phytophagous stink bugs Euschistus heros and Piezodorus guildinii in soybeans.

PubMed

Tuelher, Edmar S; Silva, Éder H; Hirose, Edson; Guedes, Raul Narciso C; Oliveira, Eugênio E

2016-10-01

The abundance and contribution of the neotropical brown stink bug, Euschistus heros (F.), and the redbanded stink bug, Piezodorus guildinii (West.), to the composition of insect pests of soybean, Glycine max (L.), fields have changed both spatially and temporally in neotropical soybean production areas. Therefore, we assessed the competitiveness of each species in direct competition experiments following an additive series. We performed mixed (adult) insect infestations in soybean plants and evaluated the fitness of each species and the soybean yield. While the competitive ability of E. heros was significantly compromised by increments in conspecifics and heterospecifics (i.e. P. guildinii), the competitive ability of P. guildinii was compromised by the presence of heterospecifics (i.e. E. heros). The reproductive output of P. guildinii remained unaffected by increments in E. heros or of P. guildinii. Intriguingly, despite the fact that P. guildinii apparently lost the competition with E. heros, almost no pod production was observed in any plant colonised by the former. The higher abundance of E. heros in neotropical soybean fields seems to result from higher competitive ability than its heterospecific competitor P. guildinii, which may prevent the higher losses caused by P. guildinii. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Intrasexual Competition and Height in Adolescents and Adults.

PubMed

Polo, P; Fernandez, A; Muñoz-Reyes, J A; Dufey, M; Buunk, A P

2018-01-01

Intrasexual competition can be defined as the struggle between members of one sex to increase their access to members of the other sex as sexual partners. In our species, height is a sexually dimorphic trait probably involved in both intrasexual and intersexual selective processes. In the present research, we examined the relationship between height and individual differences in intrasexual competitiveness (i.e., the tendency to view same-sex interactions in general in competitive terms) in two populations of adolescents and adults of both sexes in Chile. According to our first prediction, among both adolescent and adult men, height was negatively associated with intrasexual competitiveness. In contrast, among women, height was not linearly nor quadratically related with intrasexual competitiveness as previously reported. Finally, adolescent men and women showed increased levels of intrasexual competitiveness compared to adult same-sex counterparts. Our results suggest that height is a relevant trait in mating competition among men. The lack of relationship between height and intrasexual competitiveness in women may suggest that the role of height in women mating competition may be more complex and mediated by other variables.

The equivalence of numbers: The social value of avoiding health decline: An experimental web-based study

PubMed Central

Schwappach, David LB

2002-01-01

Background Health economic analysis aimed at informing policy makers and supporting resource allocation decisions has to evaluate not only improvements in health but also avoided decline. Little is known however, whether the "direction" in which changes in health are experienced is important for the public in prioritizing among patients. This experimental study investigates the social value people place on avoiding (further) health decline when directly compared to curative treatments in resource allocation decisions. Methods 127 individuals completed an interactive survey that was published in the World Wide Web. They were confronted with a standard gamble (SG) and three person trade-off tasks, either comparing improvements in health (PTO-Up), avoided decline (PTO-Down), or both, contrasting health changes of equal magnitude differing in the direction in which they are experienced (PTO-WAD). Finally, a direct priority ranking of various interventions was obtained. Results Participants strongly prioritized improving patients' health rather than avoiding decline. The mean substitution rate between health improvements and avoided decline (WAD) ranged between 0.47 and 0.64 dependent on the intervention. Weighting PTO values according to the direction in which changes in health are experienced improved their accuracy in predicting a direct prioritization ranking. Health state utilities obtained by the standard gamble method seem not to reflect social values in resource allocation contexts. Conclusion Results suggest that the utility of being cured of a given health state might not be a good approximation for the societal value of avoiding this health state, especially in cases of competition between preventive and curative interventions. PMID:11879529

Staphylococci in Competition1

PubMed Central

Peterson, A. C.; Black, J. J.; Gunderson, M. F.

1964-01-01

Previous results showed definite repressive effects on the growth of staphylococci in mixed cultures due to the competitive growth of psychrophilic saprophytes. This study was continued, and the influence of other environmental factors, pH and salt, on the competition between staphylococci and saprophytes was investigated. Initial pH values varied from 5 to 9. At the extremes of the pH range, staphylococci failed to grow, while the saprophytes grew under all of the conditions tested. At pH 5, the growth curves for the saprophytes were markedly altered from those obtained at neutral pH. The lag phases were greatly lengthened at and below 20 C, but normal numbers of saprophytes were reached in the stationary phase. At pH 6 and 8, staphylococcal growth showed the same inhibition observed at pH 7, at and below 20 C; normal multiplication was observed above this temperature, but with accelerated death phases. Thus, pH did not primarily effect staphylococcal growth through its influence on saprophyte growth and competition, but rather directly affected the growth of Staphylococcus cultures. Salt concentrations from 3.5 to 9.5% were investigated for influence on staphylococcal growth in mixed populations. Above 3.5% salt, staphylococcal inhibition at and above 20 C was not as marked as in the controls, although normal numbers were never reached. The saprophytes were increasingly inhibited, and their lag phases materially lengthened as salt concentration was increased. Salt acted directly on the Staphylococcus population and also, by repressing saprophyte growth, decreased competition, which allowed the staphylococci to grow. PMID:14106943

Steroid hormones and psychological responses to soccer matches: Insights from a systematic review and meta-analysis.

PubMed

Slimani, Maamer; Baker, Julien S; Cheour, Foued; Taylor, Lee; Bragazzi, Nicola Luigi

2017-01-01

The present systematic review and meta-analysis aimed to assess the perturbations in hormonal and psychological homeostasis in response to soccer match-play. These perturbations were explored according to match outcome (i.e., win versus loss), gender, type of contest (i.e., competitive versus non-competitive fixtures) and competitive level (i.e., novice versus high-level). The review was conducted according to the Population/Intervention or Exposure/Comparison/Outcome(s) (PICO) criteria and the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Match outcome, type of contest and competitive levels were moderator variables in the examined steroid hormones responses to a soccer match-play. Different testosterone responses were seen between match winners (increase) and losers (decrease) when compared to pre-game or baseline values (p <0.05), whilst no changes could be detected for cortisol relative to match outcome in female soccer players. Males (Δ% = 6.26; ES = 0.28) demonstrated a marginally lower increase in testosterone levels when compared to females (Δ% = 49.16; ES = 1.00), though not statistically significant. Females (Δ% = 162.7; ES = 0.98) did not demonstrate elevated cortisol match response compared to males (Δ% = 34.60; ES = 1.20). Male novice soccer match-play increased cortisol levels compared to high-level soccer match-play (Q = 18.08, p<0.001). Competitive soccer matches increased cortisol levels compared to non-competitive fixtures (i.e., collegiate tournament). Additionally, competitive levels moderate the relationship between a soccer match and testosterone levels (p <0.001), regardless of gender differences. From the presented systematic review and meta-analysis it appears (1) cortisol changes are associated with cognitive anxiety in starter female soccer players, while (2) testosterone changes are associated with changes in mood state in females and social connectedness in male soccer players. This apparent psycho-physiological relationship may proffer the opportunity for targeted intervention(s) by practitioners to favorably influence performance and/or recovery agendas. Further mechanistic and/or applied evidence is required in this regard in addition to further data sets from females.

Steroid hormones and psychological responses to soccer matches: Insights from a systematic review and meta-analysis

PubMed Central

Baker, Julien S.

2017-01-01

The present systematic review and meta-analysis aimed to assess the perturbations in hormonal and psychological homeostasis in response to soccer match-play. These perturbations were explored according to match outcome (i.e., win versus loss), gender, type of contest (i.e., competitive versus non-competitive fixtures) and competitive level (i.e., novice versus high-level). The review was conducted according to the Population/Intervention or Exposure/Comparison/Outcome(s) (PICO) criteria and the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Match outcome, type of contest and competitive levels were moderator variables in the examined steroid hormones responses to a soccer match-play. Different testosterone responses were seen between match winners (increase) and losers (decrease) when compared to pre-game or baseline values (p <0.05), whilst no changes could be detected for cortisol relative to match outcome in female soccer players. Males (Δ% = 6.26; ES = 0.28) demonstrated a marginally lower increase in testosterone levels when compared to females (Δ% = 49.16; ES = 1.00), though not statistically significant. Females (Δ% = 162.7; ES = 0.98) did not demonstrate elevated cortisol match response compared to males (Δ% = 34.60; ES = 1.20). Male novice soccer match-play increased cortisol levels compared to high-level soccer match-play (Q = 18.08, p<0.001). Competitive soccer matches increased cortisol levels compared to non-competitive fixtures (i.e., collegiate tournament). Additionally, competitive levels moderate the relationship between a soccer match and testosterone levels (p <0.001), regardless of gender differences. From the presented systematic review and meta-analysis it appears (1) cortisol changes are associated with cognitive anxiety in starter female soccer players, while (2) testosterone changes are associated with changes in mood state in females and social connectedness in male soccer players. This apparent psycho-physiological relationship may proffer the opportunity for targeted intervention(s) by practitioners to favorably influence performance and/or recovery agendas. Further mechanistic and/or applied evidence is required in this regard in addition to further data sets from females. PMID:29023546

32 CFR 22.315 - Merit-based, competitive procedures.

Code of Federal Regulations, 2014 CFR

2014-07-01

... This OMB policy directive is available at the Internet site http://www.whitehouse.gov/omb/grants/grants... accordance with that OMB policy directive, DoD Components also must post on the Internet any notice under... Component issues a specific notice with limited distribution (e.g., for national security considerations...

32 CFR 22.315 - Merit-based, competitive procedures.

Code of Federal Regulations, 2012 CFR

2012-07-01

... This OMB policy directive is available at the Internet site http://www.whitehouse.gov/omb/grants/grants... accordance with that OMB policy directive, DoD Components also must post on the Internet any notice under... Component issues a specific notice with limited distribution (e.g., for national security considerations...

32 CFR 22.315 - Merit-based, competitive procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... This OMB policy directive is available at the Internet site http://www.whitehouse.gov/omb/grants/grants... accordance with that OMB policy directive, DoD Components also must post on the Internet any notice under... Component issues a specific notice with limited distribution (e.g., for national security considerations...

Assessment of the competitive position of the forest products sector in southeast Alaska, 1985-94.

Treesearch

David J. Brooks

2001-01-01

This paper provides an assessment of the competitive position of the forest products sector in southeast Alaska relative to that of its major competitors. An analytical framework relying on the economic concepts of comparative and competitive advantage is first developed, with emphasis on the relative cost and productivity of productive inputs such as labor, capital,...

Physiological and growth responses of Centaurea maculosa (Asteraceae) to root herbivory under varying levels of interspecific plant competition and soil nitrogen availability.

PubMed

Steinger, Thomas; Müller-Schärer, Heinz

1992-08-01

Centaurea maculosa seedlings were grown in pots to study the effects of root herbivory by Agapeta zoegana L. (Lep.: Cochylidae) and Cyphocleonus achates Fahr. (Col.: Curculionidae), grass competition and nitrogen shortage (each present or absent), using a full factorial design. The aims of the study were to analyse the impact of root herbivory on plant growth, resource allocation and physiological processes, and to test if these plant responses to herbivory were influenced by plant competition and nitrogen availability. The two root herbivores differed markedly in their impact on plant growth. While feeding by the moth A. zoegana in the root cortex had no effect on shoot and root mass, feeding by the weevil C. achates in the central vascular tissue greatly reduced shoot mass, but not root mass, leading to a reduced shoot/root ratio. The absence of significant effects of the two herbivores on root biomass, despite considerable consumption, indicates that compensatory root growth occurred. Competition with grass affected plant growth more than herbivory and nutrient status, resulting in reduced shoot and root growth, and number of leaves. Nitrogen shortage did not affect plant growth directly but greatly influenced the compensatory capacity of Centaurea maculosa to root herbivory. Under high nitrogen conditions, shoot biomass of plants infested by the weevil was reduced by 30% compared with uninfested plants. However, under poor nitrogen conditions a 63% reduction was observed compared with corresponding controls. Root herbivory was the most important stress factor affecting plant physiology. Besides a relative increase in biomass allocation to the roots, infested plants also showed a significant increase in nitrogen concentration in the roots and a concomitant reduction in leaf nitrogen concentration, reflecting a redirection of the nitrogen to the stronger sink. The level of fructans was greatly reduced in the roots after herbivore feeding. This is thought to be a consequence of their mobilisation to support compensatory root growth. A preliminary model linking the effects of these root herbivores to the physiological processes of C. maculosa is presented.

Differential transcriptional regulation by alternatively designed mechanisms: A mathematical modeling approach.

PubMed

Yildirim, Necmettin; Aktas, Mehmet Emin; Ozcan, Seyma Nur; Akbas, Esra; Ay, Ahmet

2017-01-01

Cells maintain cellular homeostasis employing different regulatory mechanisms to respond external stimuli. We study two groups of signal-dependent transcriptional regulatory mechanisms. In the first group, we assume that repressor and activator proteins compete for binding to the same regulatory site on DNA (competitive mechanisms). In the second group, they can bind to different regulatory regions in a noncompetitive fashion (noncompetitive mechanisms). For both competitive and noncompetitive mechanisms, we studied the gene expression dynamics by increasing the repressor or decreasing the activator abundance (inhibition mechanisms), or by decreasing the repressor or increasing the activator abundance (activation mechanisms). We employed delay differential equation models. Our simulation results show that the competitive and noncompetitive inhibition mechanisms exhibit comparable repression effectiveness. However, response time is fastest in the noncompetitive inhibition mechanism due to increased repressor abundance, and slowest in the competitive inhibition mechanism by increased repressor level. The competitive and noncompetitive inhibition mechanisms through decreased activator abundance show comparable and moderate response times, while the competitive and noncompetitive activation mechanisms by increased activator protein level display more effective and faster response. Our study exemplifies the importance of mathematical modeling and computer simulation in the analysis of gene expression dynamics.

Unique competitive effects of lianas and trees in a tropical forest understory.

PubMed

Wright, Alexandra; Tobin, Mike; Mangan, Scott; Schnitzer, Stefan A

2015-02-01

Lianas are an important component of tropical forests, contributing up to 25% of the woody stems and 35% of woody species diversity. Lianas invest less in structural support but more in leaves compared to trees of similar biomass. These physiological and morphological differences suggest that lianas may interact with neighboring plants in ways that are different from similarly sized trees. However, the vast majority of past liana competition studies have failed to identify the unique competitive effects of lianas by controlling for the amount of biomass removed. We assessed liana competition in the forest understory over the course of 3 years by removing liana biomass and an equal amount of tree biomass in 40 plots at 10 sites in a secondary tropical moist forest in central Panama. We found that growth of understory trees and lianas, as well as planted seedlings, was limited due to competitive effects from both lianas and trees, though the competitive impacts varied by species, season, and size of neighbors. The removal of trees resulted in greater survival of planted seedlings compared to the removal of lianas, apparently related to a greater release from competition for light. In contrast, lianas had a species-specific negative effect on drought-tolerant Dipteryx oleifera seedlings during the dry season, potentially due to competition for water. We conclude that, at local scales, lianas and trees have unique and differential effects on understory dynamics, with lianas potentially competing more strongly during the dry season, and trees competing more strongly for light.

Competition for nitrogen between Fagus sylvatica and Acer pseudoplatanus seedlings depends on soil nitrogen availability

PubMed Central

Li, Xiuyuan; Rennenberg, Heinz; Simon, Judy

2015-01-01

Competition for nitrogen (N), particularly in resource-limited habitats, might be avoided by different N acquisition strategies of plants. In our study, we investigated whether slow-growing European beech and fast-growing sycamore maple seedlings avoid competition for growth-limiting N by different N uptake patterns and the potential alteration by soil N availability in a microcosm experiment. We quantified growth and biomass indices, 15N uptake capacity and N pools in the fine roots. Overall, growth indices, N acquisition and N pools in the fine roots were influenced by species-specific competition depending on soil N availability. With inter-specific competition, growth of sycamore maple reduced regardless of soil N supply, whereas beech only showed reduced growth when N was limited. Both species responded to inter-specific competition by alteration of N pools in the fine roots; however, sycamore maple showed a stronger response compared to beech for almost all N pools in roots, except for structural N at low soil N availability. Beech generally preferred organic N acquisition while sycamore maple took up more inorganic N. Furthermore, with inter-specific competition, beech had an enhanced organic N uptake capacity, while in sycamore maple inorganic N uptake capacity was impaired by the presence of beech. Although sycamore maple could tolerate the suboptimal conditions at the cost of reduced growth, our study indicates its reduced competitive ability for N compared to beech. PMID:25983738

Developmental Self-Construction and -Configuration of Functional Neocortical Neuronal Networks

PubMed Central

Bauer, Roman; Zubler, Frédéric; Pfister, Sabina; Hauri, Andreas; Pfeiffer, Michael; Muir, Dylan R.; Douglas, Rodney J.

2014-01-01

The prenatal development of neural circuits must provide sufficient configuration to support at least a set of core postnatal behaviors. Although knowledge of various genetic and cellular aspects of development is accumulating rapidly, there is less systematic understanding of how these various processes play together in order to construct such functional networks. Here we make some steps toward such understanding by demonstrating through detailed simulations how a competitive co-operative (‘winner-take-all’, WTA) network architecture can arise by development from a single precursor cell. This precursor is granted a simplified gene regulatory network that directs cell mitosis, differentiation, migration, neurite outgrowth and synaptogenesis. Once initial axonal connection patterns are established, their synaptic weights undergo homeostatic unsupervised learning that is shaped by wave-like input patterns. We demonstrate how this autonomous genetically directed developmental sequence can give rise to self-calibrated WTA networks, and compare our simulation results with biological data. PMID:25474693

{1 1 1} facet growth laws and grain competition during silicon crystallization

NASA Astrophysics Data System (ADS)

Stamelou, V.; Tsoutsouva, M. G.; Riberi-Béridot, T.; Reinhart, G.; Regula, G.; Baruchel, J.; Mangelinck-Noël, N.

2017-12-01

Directional solidification from mono-crystalline Si seeds having different orientations along the growth direction is studied. Due to the frequent twinning phenomenon, new grains soon nucleate during growth. The grain competition is then characterized in situ by imaging the dynamic evolution of the grain boundaries and of the corresponding grain boundary grooves that are formed at the solid-liquid interface. To perform this study, an experimental investigation based on Bridgman solidification technique coupled with in situ X-ray imaging is conducted in an original device: GaTSBI (Growth at high Temperature observed by X-ray Synchrotron Beam Imaging). Imaging characterisation techniques using X-ray synchrotron radiation at ESRF (European Synchrotron Radiation Facility, Grenoble, France) are applied during the solidification to study the growth dynamics. Facetted/facetted grain boundary grooves only are studied due to their importance in the grain competition because of their implication in the twinning mechanism. The maximum undercooling inside the groove is calculated from the groove depth knowing the local temperature gradient. Additionally, thanks to dynamic X-ray images, the global solid-liquid interface growth rate and the normal growth rate of the {1 1 1} facets existing at the grooves and at the edges are measured. From these measurements, experimental growth laws that correlate the normal velocity of the {1 1 1} facets with the maximum undercooling of the groove are extracted and compared to existing theoretical models. Finally, the experimental laws found for the contribution to the undercooling of the {1 1 1} facets are in good agreement with the theoretical model implying nucleation and growth eased by the presence of dislocations. Moreover, it is shown that, for the same growth parameters, the undercooling at the level of the facets (always lower than 1 K) is higher at the edges so that there is a higher probability of twin nucleation at the edges which is in agreement with the grain structure development characterised in the present experiments as well as in the literature.

Methanol-Tolerant Platinum-Palladium Catalyst Supported on Nitrogen-Doped Carbon Nanofiber for High Concentration Direct Methanol Fuel Cells

PubMed Central

Kim, Jiyoung; Jang, Jin-Sung; Peck, Dong-Hyun; Lee, Byungrok; Yoon, Seong-Ho; Jung, Doo-Hwan

2016-01-01

Pt-Pd catalyst supported on nitrogen-doped carbon nanofiber (N-CNF) was prepared and evaluated as a cathode electrode of the direct methanol fuel cell (DMFC). The N-CNF, which was directly synthesized by the catalytic chemical vapor deposition from acetonitrile at 640 °C, was verified as having a change of electrochemical surface properties such as oxygen reduction reaction (ORR) activities and the electrochemical double layer compared with common carbon black (CB). To attain the competitive oxygen reduction reaction activity with methanol tolerance, the Pt and Pd metals were supported on the CB or the N-CNF. The physical and electrochemical characteristics of the N-CNF–supported Pt-Pd catalyst were examined and compared with catalyst supported on the CB. In addition, DMFC single cells using these catalysts as the cathode electrode were applied to obtain I-V polarization curves and constant current operating performances with high-concentration methanol as the fuel. Pt-Pd catalysts had obvious ORR activity even in the presence of methanol. The higher power density was obtained at all the methanol concentrations when it applied to the membrane electrode assembly (MEA) of the DMFC. When the N-CNF is used as the catalyst support material, a better performance with high-concentration methanol is expected. PMID:28335275

Methanol-Tolerant Platinum-Palladium Catalyst Supported on Nitrogen-Doped Carbon Nanofiber for High Concentration Direct Methanol Fuel Cells.

PubMed

Kim, Jiyoung; Jang, Jin-Sung; Peck, Dong-Hyun; Lee, Byungrok; Yoon, Seong-Ho; Jung, Doo-Hwan

2016-08-15

Pt-Pd catalyst supported on nitrogen-doped carbon nanofiber (N-CNF) was prepared and evaluated as a cathode electrode of the direct methanol fuel cell (DMFC). The N-CNF, which was directly synthesized by the catalytic chemical vapor deposition from acetonitrile at 640 °C, was verified as having a change of electrochemical surface properties such as oxygen reduction reaction (ORR) activities and the electrochemical double layer compared with common carbon black (CB). To attain the competitive oxygen reduction reaction activity with methanol tolerance, the Pt and Pd metals were supported on the CB or the N-CNF. The physical and electrochemical characteristics of the N-CNF-supported Pt-Pd catalyst were examined and compared with catalyst supported on the CB. In addition, DMFC single cells using these catalysts as the cathode electrode were applied to obtain I-V polarization curves and constant current operating performances with high-concentration methanol as the fuel. Pt-Pd catalysts had obvious ORR activity even in the presence of methanol. The higher power density was obtained at all the methanol concentrations when it applied to the membrane electrode assembly (MEA) of the DMFC. When the N-CNF is used as the catalyst support material, a better performance with high-concentration methanol is expected.

A comparison of sodium borohydride as a fuel for proton exchange membrane fuel cells and for direct borohydride fuel cells

NASA Astrophysics Data System (ADS)

Wee, Jung-Ho

Two types of fuel cell systems using NaBH 4 aqueous solution as a fuel are possible: the hydrogen/air proton exchange membrane fuel cell (PEMFC) which uses onsite H 2 generated via the NaBH 4 hydrolysis reaction (B-PEMFC) at the anode and the direct borohydride fuel cell (DBFC) system which directly uses NaBH 4 aqueous solution at the anode and air at the cathode. Recently, research on these two types of fuel cells has begun to attract interest due to the various benefits of this liquid fuel for fuel cell systems for portable applications. It might therefore be relevant at this stage to evaluate the relative competitiveness of the two fuel cells. Considering their current technologies and the high price of NaBH 4, this paper evaluated and analyzed the factors influencing the relative favorability of each type of fuel cell. Their relative competitiveness was strongly dependent on the extent of the NaBH 4 crossover. When considering the crossover in DBFC systems, the total costs of the B-PEMFC system were the most competitive among the fuel cell systems. On the other hand, if the crossover problem were to be completely overcome, the total cost of the DBFC system generating six electrons (6e-DBFC) would be very similar to that of the B-PEMFC system. The DBFC system generating eight electrons (8e-DBFC) became even more competitive if the problem of crossover can be overcome. However, in this case, the volume of NaBH 4 aqueous solution consumed by the DBFC was larger than that consumed by the B-PEMFC.

Pre and Post-copulatory Selection Favor Similar Genital Phenotypes in the Male Broad Horned Beetle

PubMed Central

House, Clarissa M.; Sharma, M. D.; Okada, Kensuke; Hosken, David J.

2016-01-01

Sexual selection can operate before and after copulation and the same or different trait(s) can be targeted during these episodes of selection. The direction and form of sexual selection imposed on characters prior to mating has been relatively well described, but the same is not true after copulation. In general, when male–male competition and female choice favor the same traits then there is the expectation of reinforcing selection on male sexual traits that improve competitiveness before and after copulation. However, when male–male competition overrides pre-copulatory choice then the opposite could be true. With respect to studies of selection on genitalia there is good evidence that male genital morphology influences mating and fertilization success. However, whether genital morphology affects reproductive success in more than one context (i.e., mating versus fertilization success) is largely unknown. Here we use multivariate analysis to estimate linear and nonlinear selection on male body size and genital morphology in the flour beetle Gnatocerus cornutus, simulated in a non-competitive (i.e., monogamous) setting. This analysis estimates the form of selection on multiple traits and typically, linear (directional) selection is easiest to detect, while nonlinear selection is more complex and can be stabilizing, disruptive, or correlational. We find that mating generates stabilizing selection on male body size and genitalia, and fertilization causes a blend of directional and stabilizing selection. Differences in the form of selection across these bouts of selection result from a significant alteration of nonlinear selection on body size and a marginally significant difference in nonlinear selection on a component of genital shape. This suggests that both bouts of selection favor similar genital phenotypes, whereas the strong stabilizing selection imposed on male body size during mate acquisition is weak during fertilization. PMID:27371390

Anti-impulse-noise Edge Detection via Anisotropic Morphological Directional Derivatives.

PubMed

Shui, Peng-Lang; Wang, Fu-Ping

2017-07-13

Traditional differential-based edge detection suffers from abrupt degradation in performance when images are corrupted by impulse noises. The morphological operators such as the median filters and weighted median filters possess the intrinsic ability to counteract impulse noise. In this paper, by combining the biwindow configuration with weighted median filters, anisotropic morphological directional derivatives (AMDD) robust to impulse noise are proposed to measure the local grayscale variation around a pixel. For ideal step edges, the AMDD spatial response and directional representation are derived. The characteristics and edge resolution of two kinds of typical biwindows are analyzed thoroughly. In terms of the AMDD spatial response and directional representation of ideal step edges, the spatial matched filter is used to extract the edge strength map (ESM) from the AMDDs of an image. The spatial and directional matched filters are used to extract the edge direction map (EDM). Embedding the extracted ESM and EDM into the standard route of the differential-based edge detection, an anti-impulse-noise AMDD-based edge detector is constructed. It is compared with the existing state-of-the-art detectors on a recognized image dataset for edge detection evaluation. The results show that it attains competitive performance in noise-free and Gaussian noise cases and the best performance in impulse noise cases.

The prelimbic cortex directs attention toward predictive cues during fear learning.

PubMed

Sharpe, Melissa J; Killcross, Simon

2015-06-01

The prelimbic cortex is argued to promote conditioned fear expression, at odds with appetitive research implicating this region in attentional processing. Consistent with an attentional account, we report that the effect of prelimbic lesions on fear expression depends on the degree of competition between contextual and discrete cues. Further, when competition from contextual cues is low, we found that PL inactivation resulted in animals expressing fear toward irrelevant discrete cues; an effect selective to inactivation during the learning phase and not during retrieval. These data demonstrate that the prelimbic cortex modulates attention toward cues to preferentially direct fear responding on the basis of their predictive value. © 2015 Sharpe and Killcross; Published by Cold Spring Harbor Laboratory Press.

Cooperation and competition between two symmetry breakings in a coupled ratchet

NASA Astrophysics Data System (ADS)

Li, Chen-Pu; Chen, Hong-Bin; Fan, Hong; Xie, Ge-Ying; Zheng, Zhi-Gang

2018-03-01

We investigate the collective mechanism of coupled Brownian motors in a flashing ratchet in the presence of coupling symmetry breaking and space symmetry breaking. The dependences of directed current on various parameters are extensively studied in terms of numerical simulations and theoretical analysis. Reversed motion can be achieved by modulating multiple parameters including the spatial asymmetry coefficient, the coupling asymmetry coefficient, the coupling free length and the coupling strength. The dynamical mechanism of these transport properties can be reasonably explained by the effective potential theory and the cooperation or competition between two symmetry breakings. Moreover, adjusting the Gaussian white noise intensity, which can induce weak reversed motion under certain condition, can optimize and manipulate the directed transport of the ratchet system.

Non-competitive inhibition by active site binders.

PubMed

Blat, Yuval

2010-06-01

Classical enzymology has been used for generations to understand the interactions of inhibitors with their enzyme targets. Enzymology tools enabled prediction of the biological impact of inhibitors as well as the development of novel, more potent, ones. Experiments designed to examine the competition between the tested inhibitor and the enzyme substrate(s) are the tool of choice to identify inhibitors that bind in the active site. Competition between an inhibitor and a substrate is considered a strong evidence for binding of the inhibitor in the active site, while the lack of competition suggests binding to an alternative site. Nevertheless, exceptions to this notion do exist. Active site-binding inhibitors can display non-competitive inhibition patterns. This unusual behavior has been observed with enzymes utilizing an exosite for substrate binding, isomechanism enzymes, enzymes with multiple substrates and/or products and two-step binding inhibitors. In many of these cases, the mechanisms underlying the lack of competition between the substrate and the inhibitor are well understood. Tools like alternative substrates, testing the enzyme reaction in the reverse direction and monitoring inhibition time dependence can be applied to enable distinction between 'badly behaving' active site binders and true exosite inhibitors.

Sexual conflict over mating in Gnatocerus cornutus? Females prefer lovers not fighters.

PubMed

Okada, Kensuke; Katsuki, Masako; Sharma, Manmohan D; House, Clarissa M; Hosken, David J

2014-06-22

Female mate choice and male-male competition are the typical mechanisms of sexual selection. However, these two mechanisms do not always favour the same males. Furthermore, it has recently become clear that female choice can sometimes benefit males that reduce female fitness. So whether male-male competition and female choice favour the same or different males, and whether or not females benefit from mate choice, remain open questions. In the horned beetle, Gnatocerus cornutus, males have enlarged mandibles used to fight rivals, and larger mandibles provide a mating advantage when there is direct male-male competition for mates. However, it is not clear whether females prefer these highly competitive males. Here, we show that female choice targets male courtship rather than mandible size, and these two characters are not phenotypically or genetically correlated. Mating with attractive, highly courting males provided indirect benefits to females but only via the heritability of male attractiveness. However, mating with attractive males avoids the indirect costs to daughters that are generated by mating with competitive males. Our results suggest that male-male competition may constrain female mate choice, possibly reducing female fitness and generating sexual conflict over mating.

Comparing pre- and post-copulatory mate competition using social network analysis in wild crickets

PubMed Central

Fisher, David N.; Rodríguez-Muñoz, Rolando

2016-01-01

Sexual selection results from variation in success at multiple stages in the mating process, including competition before and after mating. The relationship between these forms of competition, such as whether they trade-off or reinforce one another, influences the role of sexual selection in evolution. However, the relationship between these 2 forms of competition is rarely quantified in the wild. We used video cameras to observe competition among male field crickets and their matings in the wild. We characterized pre- and post-copulatory competition as 2 networks of competing individuals. Social network analysis then allowed us to determine 1) the effectiveness of precopulatory competition for avoiding postcopulatory competition, 2) the potential for divergent mating strategies, and 3) whether increased postcopulatory competition reduces the apparent reproductive benefits of male promiscuity. We found 1) limited effectiveness of precopulatory competition for avoiding postcopulatory competition; 2) males do not specifically engage in only 1 type of competition; and 3) promiscuous individuals tend to mate with each other, which will tend to reduce variance in reproductive success in the population and highlights the trade-off inherent in mate guarding. Our results provide novel insights into the works of sexual competition in the wild. Furthermore, our study demonstrates the utility of using network analyses to study competitive interactions, even in species lacking obvious social structure. PMID:27174599

Comparative Analysis of OECD Member Countries' Competitive Advantage in National Human Resource Development System

ERIC Educational Resources Information Center

Oh, Hunseok; Choi, Yeseul; Choi, Myungweon

2013-01-01

The purpose of this study was to assess, evaluate, and compare the competitive advantages of the human resource development systems of advanced countries. The Global Human Resource Development Index was utilized for this study, since it has been validated through an expert panel's content review and analytic hierarchy process. Using a sample of 34…

Home Advantage in Men's and Women's Spanish First and Second Division Water Polo Leagues.

PubMed

Prieto, Jaime; Gómez, Miguel-Ángel; Pollard, Richard

2013-01-01

The purpose of this study was to quantify the home advantage in both men's and women's First and Second Division water polo leagues, to compare the results obtained according to sex of participants and the level of competition, and to test for possible differences in home advantage when considering the interaction between these two factors. The sample comprised four seasons from 2007-2008 to 2010-2011 for a total of 1942 games analyzed. The results showed the existence of home advantage in both men's and women's First and Second Divisions. After controlling for the competitive balance of each league in each season, there was a significant difference between men's and women's leagues, with higher home advantage for men's leagues (58.60% compared with 53.70% for women's leagues). There was also a significant difference between the levels of competition, with greater home advantage for the Second Division (57.95% compared with 54.35% for First Division). No significant differences in home advantage were found when considering the interaction between sex of participants and the level of competition. The results in relation to sex of participants and the level of competition are consistent with previous studies in other sports such as football or handball.

Home Advantage in Men’s and Women’s Spanish First and Second Division Water Polo Leagues

PubMed Central

Prieto, Jaime; Gómez, Miguel-Ángel; Pollard, Richard

The purpose of this study was to quantify the home advantage in both men’s and women’s First and Second Division water polo leagues, to compare the results obtained according to sex of participants and the level of competition, and to test for possible differences in home advantage when considering the interaction between these two factors. The sample comprised four seasons from 2007–2008 to 2010–2011 for a total of 1942 games analyzed. The results showed the existence of home advantage in both men’s and women’s First and Second Divisions. After controlling for the competitive balance of each league in each season, there was a significant difference between men’s and women’s leagues, with higher home advantage for men’s leagues (58.60% compared with 53.70% for women’s leagues). There was also a significant difference between the levels of competition, with greater home advantage for the Second Division (57.95% compared with 54.35% for First Division). No significant differences in home advantage were found when considering the interaction between sex of participants and the level of competition. The results in relation to sex of participants and the level of competition are consistent with previous studies in other sports such as football or handball. PMID:24146714

Influence of training and competitive sessions on peripheral β-endorphin levels in training show jumping horses

PubMed Central

Cravana, Cristina; Medica, P.; Ragonese, G.; Fazio, E.

2017-01-01

Aim: To investigate the effects of training sessions on circulating β-endorphin changes in sport horses before and after competition and to ascertain whether competition would affect this response. Materials and Methods: A total of 24 trained jumping horses were randomly assigned to one of two training groups: Group A (competing) and Group B (not competing). To determined plasma β-endorphin concentrations, two pre- and post-competition training weeks at aerobic workout and two competitive show jumping event days at anaerobic workout were measured before, 5 and 30 min after exercise. Exercise intensity is described using lactate concentrations and heart rate. The circuit design, intensity, and duration of training sessions were the same for both groups. Results: In Group A, one-way analysis of variance for repeated measures (RM-ANOVA) showed significant effects of exercise on β-endorphin changes (F=14.41; p<0.001), only in the post-competition training sessions, while in Group B showed no significant effects. Two-way RM-ANOVA showed, after post-competition training sessions, a significant difference between Group A and Group B (F=6.235; p=0.023), with higher β-endorphin changes in Group A, compared to Group B. During the competitive show jumping sessions, one-way RM ANOVA showed significant effects of exercise on β-endorphin changes (F=51.10; p<0.001). The statistical analysis, in Group A, showed a significant difference between post-competition training and competitive exercise (F=6.32; p=0.024) with higher β-endorphin values in competitive sessions compared to those of post-competition training. Conclusion: Lactate concentrations seem to be the main factors being correlated with the raise of β-endorphin during anaerobic exercise of competitive events. Exercise of low intensity, as well as that one of training sessions, does not appear to stimulate a significant increased release of β-endorphin and it may depend on the duration of the exercise program. Moreover, the responses during exercise in the course of post-competition training sessions seem to be significantly different from those the pre-competition training. These data show that the preliminary competitive stress induced additional significant changes of β-endorphin pattern. It would reflect the need of a long-lasting modulation of fatigue and pain perception related to the effect of an additional physical and mental effort for the consecutive competitive and training sessions. PMID:28246449

The competitive advantage of sanctioning institutions.

PubMed

Gürerk, Ozgür; Irlenbusch, Bernd; Rockenbach, Bettina

2006-04-07

Understanding the fundamental patterns and determinants of human cooperation and the maintenance of social order in human societies is a challenge across disciplines. The existing empirical evidence for the higher levels of cooperation when altruistic punishment is present versus when it is absent systematically ignores the institutional competition inherent in human societies. Whether punishment would be deliberately adopted and would similarly enhance cooperation when directly competing with nonpunishment institutions is highly controversial in light of recent findings on the detrimental effects of punishment. We show experimentally that a sanctioning institution is the undisputed winner in a competition with a sanction-free institution. Despite initial aversion, the entire population migrates successively to the sanctioning institution and strongly cooperates, whereas the sanction-free society becomes fully depopulated. The findings demonstrate the competitive advantage of sanctioning institutions and exemplify the emergence and manifestation of social order driven by institutional selection.

Common Priority Map for Selection History, Reward and Emotion in the Oculomotor System.

PubMed

Belopolsky, Artem V

2015-01-01

In natural scenes, many objects compete for visual selection. However, it is not always clear why certain objects win this competition. I will demonstrate that the eye movement system lives in a constant state of competition among different oculomotor programs. This competition is not limited to the competition between the current goals of the observer and salient objects in the environment but incorporates independent influences from memory, reward, and emotional systems. These involuntary and automatic biases often overcome the goal-directed selection and expose severe limits in goal-driven control. There is also a striking similarity in the way that these very different sources of bias activate the oculomotor system and compete for representation. The inputs from various information sources are integrated in the common map in the oculomotor system for the sole purpose of improving the efficiency of oculomotor selection. © The Author(s) 2015.

Larval Competition Reduces Body Condition in the Female Seed Beetle, Callosobruchus maculatus

PubMed Central

Schade, Daynika J.; Vamosi, Steven M.

2012-01-01

Early body condition may be important for adult behavior and fitness, and is impacted by a number of environmental conditions and biotic interactions. Reduced fecundity of adult females exposed to larval competition may be caused by reduced body condition or shifts in relative body composition, yet these mechanisms have not been well researched. Here, body mass, body size, scaled body mass index, and two body components (water content and lean dry mass) of adult Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae: Bruchinae) females exposed to larval competition or reared alone were examined. Experimental females emerged at significantly smaller body mass and body size than control females. Additionally, scaled body mass index and water content, but not lean dry mass, were significantly reduced in experimental females. To our knowledge, these are the first results that demonstrate a potential mechanism for previously documented direct effects of competition on fecundity in female bruchine beetles. PMID:22954282

Larval competition reduces body condition in the female seed beetle, Callosobruchus maculatus.

PubMed

Schade, Daynika J; Vamosi, Steven M

2012-01-01

Early body condition may be important for adult behavior and fitness, and is impacted by a number of environmental conditions and biotic interactions. Reduced fecundity of adult females exposed to larval competition may be caused by reduced body condition or shifts in relative body composition, yet these mechanisms have not been well researched. Here, body mass, body size, scaled body mass index, and two body components (water content and lean dry mass) of adult Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae: Bruchinae) females exposed to larval competition or reared alone were examined. Experimental females emerged at significantly smaller body mass and body size than control females. Additionally, scaled body mass index and water content, but not lean dry mass, were significantly reduced in experimental females. To our knowledge, these are the first results that demonstrate a potential mechanism for previously documented direct effects of competition on fecundity in female bruchine beetles.

Sustainable competitive advantage for accountable care organizations.

PubMed

Macfarlane, Michael Alex

2014-01-01

In the current period of health industry reform, accountable care organizations (ACOs) have emerged as a new model for the delivery of high-quality and cost-effective healthcare. However, few ACOs operate in direct competition with one another, and the accountable care business model has yet to present a means of continually developing new marginal value for patients and network partners. With value-based purchasing and patient consumerism strengthening as market forces, ACOs must build organizational sustainability and competitive advantage to meet the value demands set by customers and competitors. This essay proposes a strategy, adapted from the disciplines of agile software development and Lean product development, through which ACOs can engage internal and external customers in the development of new products that will provide sustainability and competitive advantage to the organization by decreasing waste in development, promoting specialized knowledge, and closely targeting customer value.

The Effects of Dynamical Rates on Species Coexistence in a Variable Environment: The Paradox of the Plankton Revisited.

PubMed

Li, Lina; Chesson, Peter

2016-08-01

Hutchinson's famous hypothesis for the "paradox of the plankton" has been widely accepted, but critical aspects have remained unchallenged. Hutchinson argued that environmental fluctuations would promote coexistence when the timescale for environmental change is comparable to the timescale for competitive exclusion. Using a consumer-resource model, we do find that timescales of processes are important. However, it is not the time to exclusion that must be compared with the time for environmental change but the time for resource depletion. Fast resource depletion, when resource consumption is favored for different species at different times, strongly promotes coexistence. The time for exclusion is independent of the rate of resource depletion. Therefore, the widely believed predictions of Hutchinson are misleading. Fast resource depletion, as determined by environmental conditions, ensures strong coupling of environmental processes and competition, which leads to enhancement over time of intraspecific competition relative to interspecific competition as environmental shifts favor different species at different times. This critical coupling is measured by the covariance between environment and competition. Changes in this quantity as densities change determine the stability of coexistence and provide the key to rigorous analysis, both theoretically and empirically, of coexistence in a variable environment. These ideas apply broadly to diversity maintenance in variable environments whether the issue is species diversity or genetic diversity and competition or apparent competition.

Players' expertise and competition with others shape the satisfaction of competence needs, gaming gratifications, and contingent self-esteem in a gaming context.

PubMed

Kazakova, Snezhanka; Cauberghe, Veroline; Pandelaere, Mario; De Pelsmacker, Patrick

2014-01-01

The current study explores how competition and gaming expertise affect the satisfaction of competence needs and gaming gratifications. We demonstrate that competition moderates the effect of gaming expertise on the satisfaction of competence needs, which in turn affects game enjoyment and replay intention. Gaming expertise predicted players' need satisfaction, game enjoyment, and replay intention significantly better in a competitive compared to a noncompetitive context. The effect of gaming expertise on game enjoyment and replay intention was, furthermore, mediated by the satisfaction of competence needs. Finally, gaming expertise positively affected the importance of competition for players' self-esteem only in the competitive gaming context. The present findings demonstrate the importance of competition and gaming expertise for the satisfaction of competence needs, gaming gratifications, and the pursuit of self-esteem during gameplay, attesting to the applicability of self-determination theory to gaming contexts.

Cell Competition: Roles and Importance as a Central Phenomenon.

PubMed

Patel, Manish; Antala, Bhavesh; Shrivastava, Neeta

2015-01-01

Cell competition is a type of short-range cell-cell interaction first observed in Drosophila melanogaster. In two heterogeneous cell populations, cells that have a higher fitness level would have a competitive advantage and grow at the cost of neighbor cells that have comparatively lower fitness. This interaction is due to differences in expression levels of a specific protein in the two cell populations, and it is known as cell competition. In this review, we have studied recent findings of cell competition in different biological processes in Drosophila as well as mammalian systems. The purpose of this review is to collate important studies of competitive cell interactions, and to understand its roles and importance as a central phenomenon. This review provides evidence of the relevance of cell competition in various physiological and pathological conditions, such as size control in organ development, stem cell maintenance, tissue repair, organ regeneration, aging, formation of memory, and cancer.

Affirmative action policies promote women and do not harm efficiency in the laboratory.

PubMed

Balafoutas, Loukas; Sutter, Matthias

2012-02-03

Gender differences in choosing to enter competitions are one source of unequal labor market outcomes concerning wages and promotions. Given that studying the effects of policy interventions to support women is difficult with field data because of measurement problems and potential lack of control, we evaluated, in a set of controlled laboratory experiments, four interventions: quotas, where one of two winners of a competition must be female; two variants of preferential treatment, where a fixed increment is added to women's performance; and repetition of the competition, where a second competition takes place if no woman is among the winners. Compared with no intervention, all interventions encourage women to enter competitions more often, and performance is at least equally good, both during and after the competition.

Influence of herbivory and competition on invasive weed fitness: Observed effects of Cyphocleonus achates (Coleoptera: Curculionidae) and grass-seeding treatments on spotted knapweed performance

Treesearch

James S. Jacobs; Sharlene E. Sing; John M. Martin

2006-01-01

The root-feeding weevil Cyphocleonus achates (Fahraeus) is a promising biological control agent for managing the exotic, invasive weed spotted knapweed. The objective of this study was to compare the relative and potentially interactive effects of competition and specialized herbivory on spotted knapweed fitness. Competition was assessed through three grass seeding...

Comparison of Anthropometry and Lower Limb Power Qualities According to Different Levels and Ranking Position of Competitive Surfers.

PubMed

Fernandez-Gamboa, Iosu; Yanci, Javier; Granados, Cristina; Camara, Jesus

2017-08-01

Fernandez-Gamboa, I, Yanci, J, Granados, C, and Camara, J. Comparison of anthropometry and lower limb power qualities according to different levels and ranking position of competitive surfers. J Strength Cond Res 31(8): 2231-2237, 2017-The aim of this study was to compare competitive surfers' lower limb power output depending on their competitive level, and to evaluate the association between competition rankings. Twenty competitive surfers were divided according to the competitive level as follows: international (INT) or national (NAT), and competitive ranking (RANK1-50 or RANK51-100). Vertical jump and maximal peak power of the lower limbs were measured. No differences were found between INT and NAT surfers in the anthropometric variables, in the vertical jump, or in lower extremity power; although the NAT group had higher levels on the elasticity index, squat jumps (SJs), and counter movement jumps (CMJs) compared with the INT group. The RANK1-50 group had a lower biceps skinfold (p < 0.01), lower skinfolds in the legs (Front thigh: p ≤ 0.05; medial calf: p < 0.01), lower sum of skinfolds (p ≤ 0.05), higher SJ (p < 0.01), CMJ (p < 0.01), and 15 seconds vertical CMJ (p ≤ 0.05); also, maximal peak power of the right leg (MPPR) and left leg (MPPL) were higher in the RANK1-50 group. Moderate to large significant correlations were obtained between the surfers' ranking position and some skinfolds, the sum of skinfolds, and vertical jump. Results demonstrate that surfers' physical performance seems to be an accurate indicator of ranking positioning, also revealing that vertical jump capacity and anthropometric variables play an important role in their competitive performance, which may be important when considering their power training.

Postmating sexual selection: allopatric evolution of sperm competition mechanisms and genital morphology in calopterygid damselflies (Insecta: Odonata).

PubMed

Cordero Rivera, A; Andrés, J A; Córdoba-Aguilar, A; Utzeri, C

2004-02-01

Postmating sexual selection theory predicts that in allopatry reproductive traits diverge rapidly and that the resulting differentiation in these traits may lead to restrictions to gene flow between populations and, eventually, reproductive isolation. In this paper we explore the potential for this premise in a group of damselflies of the family Calopterygidae, in which postmating sexual mechanisms are especially well understood. Particularly, we tested if in allopatric populations the sperm competition mechanisms and genitalic traits involved in these mechanisms have indeed diverged as sexual selection theory predicts. We did so in two different steps. First, we compared the sperm competition mechanisms of two allopatric populations of Calopteryx haemorrhoidalis (one Italian population studied here and one Spanish population previously studied). Our results indicate that in both populations males are able to displace spermathecal sperm, but the mechanism used for sperm removal between both populations is strikingly different. In the Spanish population males seem to empty the spermathecae by stimulating females, whereas in the Italian population males physically remove sperm from the spermathecae. Both populations also exhibit differences in genital morphometry that explain the use of different mechanisms: the male lateral processes are narrower than the spermathecal ducts in the Italian population, which is the reverse in the Spanish population. The estimated degree of phenotypic differentiation between these populations based on the genitalic traits involved in sperm removal was much greater than the differentiation based on a set of other seven morphological variables, suggesting that strong directional postmating sexual selection is indeed the main evolutionary force behind the reproductive differentiation between the studied populations. In a second step, we examined if a similar pattern in genital morphometry emerge in allopatric populations of this and other three species of the same family (Calopteryx splendens, C. virgo and Hetaerina cruentata). Our results suggest that there is geographic variation in the sperm competition mechanisms in all four studied species. Furthermore, genitalic morphology was significantly divergent between populations within species even when different populations were using the same copulatory mechanism. These results can be explained by probable local coadaptation processes that have given rise to an ability or inability to reach and displace spermathecal sperm in different populations. This set of results provides the first direct evidence of intraspecific evolution of genitalic traits shaped by postmating sexual selection.

48 CFR 927.402-2 - Policy.

Code of Federal Regulations, 2012 CFR

2012-10-01

... directed toward achieving the following objectives: (a) Making the benefits of the energy research...; and (d) Fostering competition and preventing undue market concentration or the creation or maintenance...

48 CFR 927.402-2 - Policy.

Code of Federal Regulations, 2013 CFR

2013-10-01

... directed toward achieving the following objectives: (a) Making the benefits of the energy research...; and (d) Fostering competition and preventing undue market concentration or the creation or maintenance...

48 CFR 927.402-2 - Policy.

Code of Federal Regulations, 2014 CFR

2014-10-01

... directed toward achieving the following objectives: (a) Making the benefits of the energy research...; and (d) Fostering competition and preventing undue market concentration or the creation or maintenance...

48 CFR 927.402-2 - Policy.

Code of Federal Regulations, 2011 CFR

2011-10-01

... directed toward achieving the following objectives: (a) Making the benefits of the energy research...; and (d) Fostering competition and preventing undue market concentration or the creation or maintenance...

48 CFR 927.402-2 - Policy.

Code of Federal Regulations, 2010 CFR

2010-10-01

... directed toward achieving the following objectives: (a) Making the benefits of the energy research...; and (d) Fostering competition and preventing undue market concentration or the creation or maintenance...

Clusters and the new economics of competition.

PubMed

Porter, M E

1998-01-01

Economic geography in an era of global competition poses a paradox. In theory, location should no longer be a source of competitive advantage. Open global markets, rapid transportation, and high-speed communications should allow any company to source any thing from any place at any time. But in practice, Michael Porter demonstrates, location remains central to competition. Today's economic map of the world is characterized by what Porter calls clusters: critical masses in one place of linked industries and institutions--from suppliers to universities to government agencies--that enjoy unusual competitive success in a particular field. The most famous example are found in Silicon Valley and Hollywood, but clusters dot the world's landscape. Porter explains how clusters affect competition in three broad ways: first, by increasing the productivity of companies based in the area; second, by driving the direction and pace of innovation; and third, by stimulating the formation of new businesses within the cluster. Geographic, cultural, and institutional proximity provides companies with special access, closer relationships, better information, powerful incentives, and other advantages that are difficult to tap from a distance. The more complex, knowledge-based, and dynamic the world economy becomes, the more this is true. Competitive advantage lies increasingly in local things--knowledge, relationships, and motivation--that distant rivals cannot replicate. Porter challenges the conventional wisdom about how companies should be configured, how institutions such as universities can contribute to competitive success, and how governments can promote economic development and prosperity.

78 FR 55776 - Hainesport Industrial Railroad, LLC-Corporate Family Transaction Exemption

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-11

...).\\1\\ Hainesport states that several sidings point in an easterly direction (East Line) and one or more sidings point in a southerly direction (South Line). Hainesport proposes to establish a new corporate... the competitive balance with carriers outside the corporate family. Under 49 U.S.C. 10502(g), the...

75 FR 70699 - Notice of Determinations Regarding Eligibility To Apply for Worker Adjustment Assistance

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-18

... decreased absolutely; and (3) One of the following must be satisfied: (A) Imports of articles or services like or directly competitive with articles produced or services supplied by such firm have increased... which are produced directly using services supplied by such firm, have increased; and (4) The increase...

Effects of competition on great and blue tit reproduction: intensity and importance in relation to habitat quality.

PubMed

Dhondt, André A

2010-01-01

1. In studies on the effect of competition in plant communities two terms are used to describe its effects: the absolute reduction in growth of an individual as a consequence of the presence of another one is called intensity, while the relative impact of competition on an individual as a proportion of the impact of the whole environment is called importance. One school of thought is that the role of competition remains constant across productivity gradients, while the other is that it decreases with increasing severity. J.B. Grace (1991. A clarification of the debate between grime and tilman. Functional Ecology, 5, 583-587.) suggested that the apparent contradiction might be solved if we acknowledge that the two schools are discussing different aspects of competition: the intensity of competition might remain constant while its importance declines with increasing severity. 2. There are no studies that compare intensity and importance of competition in bird populations between areas that differ in quality or productivity and hence it is not possible to make predictions how intensity or importance of competition would vary between them. 3. I compared variation in intensity and importance of competition of three demographic variables between five plots that differ strongly in quality for great Parus major L. and blue tit Cyanistes caeruleus (L.). 4. Both intensity and importance of competition are larger in great than in blue tit populations meaning that the effect of competition on demographic variables is stronger in great than in blue tits and that the contribution of competition to variation in these variables is relatively higher in great than in blue tits. 5. Intensity of competition is higher in low quality than in high quality plots for both species, a result not expected from studies in plant communities. 6. Importance of competition varies strongly between plots. It is larger in oak-dominated plots than in mixed deciduous plots. 7. In birds breeding density increases with habitat quality but is limited by territorial behaviour. As a result competition for food is reduced in high quality habitats resulting in a reduction of competition intensity in high quality sites in which birds breed at high densities. 8. It can be predicted that in studies of territorial species density dependent effects on reproduction are more likely to be detected in low quality sites explaining in part differences in results between studies.

Comparing susceptibility of eastern and western U.S. grasslands to competition and allelopathy from spotted knapweed (Centaurea stoebe L. subsp. micranthos (Gugler) Hayek)

USDA-ARS?s Scientific Manuscript database

Centaurea maculosa is native to Eurasia and is invasive in the western portion of the US. Negative impacts of C. maculosa present in the eastern US have not been recorded. In this study, we examine the effects of C. maculosa on species diversity on an eastern grassy bald, compare the competitive a...

Endogenous miRNA and Target Concentrations Determine Susceptibility to Potential ceRNA Competition

PubMed Central

Bosson, Andrew D.; Zamudio, Jesse R.; Sharp, Phillip A.

2016-01-01

SUMMARY Target competition (ceRNA crosstalk) within miRNA-regulated gene networks has been proposed to influence biological systems. To assess target competition, we characterize and quantitate miRNA networks in two cell types. Argonaute iCLIP reveals that hierarchical binding of high- to low-affinity miRNA targets is a key characteristic of in vivo activity. Quantification of cellular miRNA and mRNA/ncRNA target pool levels indicates that miRNA:target pool ratios and an affinity partitioned target pool accurately predict in vivo Ago binding profiles and miRNA susceptibility to target competition. Using single-cell reporters, we directly test predictions and estimate that ~3,000 additional high-affinity target sites can affect active miRNA families with low endogenous miRNA:target ratios, such as miR-92/25. In contrast, the highly expressed miR-294 and let-7 families are not susceptible to increases of nearly 10,000 sites. These results show differential susceptibility based on endogenous miRNA:target pool ratios and provide a physiological context for ceRNA competition in vivo. PMID:25449132

A solution to the biodiversity paradox by logical deterministic cellular automata.

PubMed

Kalmykov, Lev V; Kalmykov, Vyacheslav L

2015-06-01

The paradox of biological diversity is the key problem of theoretical ecology. The paradox consists in the contradiction between the competitive exclusion principle and the observed biodiversity. The principle is important as the basis for ecological theory. On a relatively simple model we show a mechanism of indefinite coexistence of complete competitors which violates the known formulations of the competitive exclusion principle. This mechanism is based on timely recovery of limiting resources and their spatio-temporal allocation between competitors. Because of limitations of the black-box modeling there was a problem to formulate the exclusion principle correctly. Our white-box multiscale model of two-species competition is based on logical deterministic individual-based cellular automata. This approach provides an automatic deductive inference on the basis of a system of axioms, and gives a direct insight into mechanisms of the studied system. It is one of the most promising methods of artificial intelligence. We reformulate and generalize the competitive exclusion principle and explain why this formulation provides a solution of the biodiversity paradox. In addition, we propose a principle of competitive coexistence.

Competition and facilitation may lead to asymmetric range shift dynamics with climate change.

PubMed

Ettinger, Ailene; HilleRisLambers, Janneke

2017-09-01

Forecasts of widespread range shifts with climate change stem from assumptions that climate drives species' distributions. However, local adaptation and biotic interactions also influence range limits and thus may impact range shifts. Despite the potential importance of these factors, few studies have directly tested their effects on performance at range limits. We address how population-level variation and biotic interactions may affect range shifts by transplanting seeds and seedlings of western North American conifers of different origin populations into different competitive neighborhoods within and beyond their elevational ranges and monitoring their performance. We find evidence that competition with neighboring trees limits performance within current ranges, but that interactions between adults and juveniles switch from competitive to facilitative at upper range limits. Local adaptation had weaker effects on performance that did not predictably vary with range position or seed origin. Our findings suggest that competitive interactions may slow species turnover within forests at lower range limits, whereas facilitative interactions may accelerate the pace of tree expansions upward near timberline. © 2017 John Wiley & Sons Ltd.

Pollinator-mediated selection in a specialized hummingbird-Heliconia system in the Eastern Caribbean.

PubMed

Temeles, E J; Rah, Y J; Andicoechea, J; Byanova, K L; Giller, G S J; Stolk, S B; Kress, W J

2013-02-01

Phenotypic matches between plants and their pollinators often are interpreted as examples of reciprocal selection and adaptation. For the two co-occurring plant species, Heliconia bihai and H. caribaea in the Eastern Caribbean, we evaluated for five populations over 2 years the strength and direction of natural selection on corolla length and number of bracts per inflorescence. These plant traits correspond closely to the bill lengths and body masses of their primary pollinators, female or male purple-throated carib hummingbirds (Eulampis jugularis). In H. bihai, directional selection for longer corollas was always significant with the exception of one population in 1 year, whereas selection on bract numbers was rare and found only in one population in 1 year. In contrast, significant directional selection for more bracts per inflorescence occurred in all three populations of the yellow morph and in two populations of the red morph of H. caribaea, whereas significant directional selection on corolla length occurred in only one population of the red morph and one population of the yellow morph. Selection for longer corollas in H. bihai may result from better mechanical fit, and hence pollination, by the long bills of female E. jugularis, their sole pollinator. In contrast, competition between males of E. jugularis for territories may drive selection for more bracts in H. caribaea. Competitive exclusion of female E. jugularis by territorial males also implicates pollinator competition as a possible ecological mechanism for trait diversification in these plants. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

Biosimilars: How Can Payers Get Long-Term Savings?

PubMed

Mestre-Ferrandiz, Jorge; Towse, Adrian; Berdud, Mikel

2016-06-01

The term 'biosimilar' refers to an alternative similar version of an off-patent innovative originator biotechnology product (the 'reference product'). Several biosimilars have been approved in Europe, and a number of top-selling biological medicines have lost, or will lose, patent protection over the next 5 years. We look at the experience in Europe so far. The USA has finally implemented a regulatory route for biosimilar approval. We recommend that European and US governments and payers take a strategic approach to get value for money from the use of biosimilars by (1) supporting and incentivising generation of high-quality comprehensive outcomes data on the effectiveness and safety of biosimilars and originator products; and (2) ensuring that incentives are in place for budget holders to benefit from price competition. This may create greater willingness on the part of budget holders and clinicians to use biosimilar and originator products with comparable outcomes interchangeably, and may drive down prices. Other options, such as direct price cuts for originator products or substitution rules without outcomes data, are likely to discourage biosimilar entry. With such approaches, governments may achieve a one-off cut in originator prices but may put at risk the creation of a more competitive market that would, in time, produce much greater savings. It was the creation of competitive markets for chemical generic drugs-notably, in the USA, the UK and Germany-rather than price control, that enabled payers to achieve the high discounts now taken for granted.

Spatial and Dietary Overlap Creates Potential for Competition between Red Snapper (Lutjanus campechanus) and Vermilion snapper (Rhomboplites aurorubens)

PubMed Central

Davis, William T.; Drymon, J. Marcus; Powers, Sean P.

2015-01-01

Understanding the complex nature of direct and indirect species interactions is a critical precursor to successful resource management. In the northern Gulf of Mexico fisheries ecosystem, red snapper (Lutjanus campechanus) and vermilion snapper (Rhomboplites aurorubens) are two commercially harvested species within a larger reef fish complex. These two species share similar habitats and diets; however, little is known about how these species partition habitat and dietary resources. In this study we examined the extent of spatial and dietary overlap between red snapper and vermilion snapper, and experimentally compared their feeding behavior. Field data from multiple gear types demonstrates that red snapper and vermilion snapper frequently cohabited reefs in the northern Gulf of Mexico, and Pianka’s niche overlap indices suggest significantly overlapping diets. Experimental manipulations show that red snapper are the dominant forager of the two species, as red snapper foraging alone ate more shrimp per fish than vermilion snapper in both the single species (p = 0.003) and mixed species (p = 0.02) treatments. In addition, red snapper ate significantly more shrimp per fish in the mixed species treatment than in the single species treatment (p = 0.04). Vermilion snapper shrimp consumption per fish did not differ significantly between mixed and single species treatments. Cumulatively, our results suggest that spatial and dietary overlap could lead to competition between red and vermilion snapper in the study area; however, conclusively determining the existence of such competition would require further research. PMID:26630481

Spatial and Dietary Overlap Creates Potential for Competition between Red Snapper (Lutjanus campechanus) and Vermilion snapper (Rhomboplites aurorubens).

PubMed

Davis, William T; Drymon, J Marcus; Powers, Sean P

2015-01-01

Understanding the complex nature of direct and indirect species interactions is a critical precursor to successful resource management. In the northern Gulf of Mexico fisheries ecosystem, red snapper (Lutjanus campechanus) and vermilion snapper (Rhomboplites aurorubens) are two commercially harvested species within a larger reef fish complex. These two species share similar habitats and diets; however, little is known about how these species partition habitat and dietary resources. In this study we examined the extent of spatial and dietary overlap between red snapper and vermilion snapper, and experimentally compared their feeding behavior. Field data from multiple gear types demonstrates that red snapper and vermilion snapper frequently cohabited reefs in the northern Gulf of Mexico, and Pianka's niche overlap indices suggest significantly overlapping diets. Experimental manipulations show that red snapper are the dominant forager of the two species, as red snapper foraging alone ate more shrimp per fish than vermilion snapper in both the single species (p = 0.003) and mixed species (p = 0.02) treatments. In addition, red snapper ate significantly more shrimp per fish in the mixed species treatment than in the single species treatment (p = 0.04). Vermilion snapper shrimp consumption per fish did not differ significantly between mixed and single species treatments. Cumulatively, our results suggest that spatial and dietary overlap could lead to competition between red and vermilion snapper in the study area; however, conclusively determining the existence of such competition would require further research.

Accumulation of Reserve Carbohydrate by Rumen Protozoa and Bacteria in Competition for Glucose

PubMed Central

Denton, Bethany L.; Diese, Leanne E.; Firkins, Jeffrey L.

2014-01-01

The aim of this study was to determine if rumen protozoa could form large amounts of reserve carbohydrate compared to the amounts formed by bacteria when competing for glucose in batch cultures. We separated large protozoa and small bacteria from rumen fluid by filtration and centrifugation, recombined equal protein masses of each group into one mixture, and subsequently harvested (reseparated) these groups at intervals after glucose dosing. This method allowed us to monitor reserve carbohydrate accumulation of protozoa and bacteria individually. When mixtures were dosed with a moderate concentration of glucose (4.62 or 5 mM) (n = 2 each), protozoa accumulated large amounts of reserve carbohydrate; 58.7% (standard error of the mean [SEM], 2.2%) glucose carbon was recovered from protozoal reserve carbohydrate at time of peak reserve carbohydrate concentrations. Only 1.7% (SEM, 2.2%) was recovered in bacterial reserve carbohydrate, which was less than that for protozoa (P < 0.001). When provided a high concentration of glucose (20 mM) (n = 4 each), 24.1% (SEM, 2.2%) of glucose carbon was recovered from protozoal reserve carbohydrate, which was still higher (P = 0.001) than the 5.0% (SEM, 2.2%) glucose carbon recovered from bacterial reserve carbohydrate. Our novel competition experiments directly demonstrate that mixed protozoa can sequester sugar away from bacteria by accumulating reserve carbohydrate, giving protozoa a competitive advantage and stabilizing fermentation in the rumen. Similar experiments could be used to investigate the importance of starch sequestration. PMID:25548053

An empirical investigation of spatial differentiation and price floor regulations in retail markets for gasoline

NASA Astrophysics Data System (ADS)

Houde, Jean-Francois

In the first essay of this dissertation, I study an empirical model of spatial competition. The main feature of my approach is to formally specify commuting paths as the "locations" of consumers in a Hotelling-type model of spatial competition. The main consequence of this location assumption is that the substitution patterns between stations depend in an intuitive way on the structure of the road network and the direction of traffic flows. The demand-side of the model is estimated by combining a model of traffic allocation with econometric techniques used to estimate models of demand for differentiated products (Berry, Levinsohn and Pakes (1995)). The estimated parameters are then used to evaluate the importance of commuting patterns in explaining the distribution of gasoline sales, and compare the economic predictions of the model with the standard home-location model. In the second and third essays, I examine empirically the effect of a price floor regulation on the dynamic and static equilibrium outcomes of the gasoline retail industry. In particular, in the second essay I study empirically the dynamic entry and exit decisions of gasoline stations, and measure the impact of a price floor on the continuation values of staying in the industry. In the third essay, I develop and estimate a static model of quantity competition subject to a price floor regulation. Both models are estimated using a rich panel dataset on the Quebec gasoline retail market before and after the implementation of a price floor regulation.

Effects of regular away travel on training loads, recovery, and injury rates in professional Australian soccer players.

PubMed

Fowler, Peter; Duffield, Rob; Waterson, Adam; Vaile, Joanna

2015-07-01

The current study examined the acute and longitudinal effects of regular away travel on training load (TL), player wellness, and injury surrounding competitive football (soccer) matches. Eighteen male professional football players, representing a team competing in the highest national competition in Australia, volunteered to participate in the study. Training loads, player wellness and injury incidence, rate, severity, and type, together with the activity at the time of injury, were recorded on the day before, the day of, and for 4 d after each of the 27 matches of the 2012-13 season. This included 14 home and 13 away matches, further subdivided based on the midpoint of the season into early (1-13) and late competition (14-27) phases. While TLs were significantly greater on day 3 at home compared with away during the early competition phase (P=.03), no other significant effects of match location were identified (P>.05). Total TL and mean wellness over the 6 d surrounding matches and TL on day 3 were significantly reduced during the late compared with the early competition phase at home and away (P<.05). Although not significantly (P>.05), training missed due to injury was 60% and 50% greater during the late than during the early competition phase at home and away, respectively. In conclusion, no significant interactions between match location and competition phase were evident during the late competition phase, which suggests that away travel had negligible cumulative effects on the reduction in player wellness in the latter half of the season.

Life-history traits of alien and native senecio species in the Mediterranean region

NASA Astrophysics Data System (ADS)

Sans, F. X.; Garcia-Serrano, H.; Afán, I.

2004-12-01

Two related shrubs, Senecio inaequidens and S. pterophorus, both introduced to western Mediterranean Europe from South Africa, were compared with a native Mediterranean shrub, S. malacitanus, to identify life-history traits that confer invasive ability. We examined ecological interactions that affect seedling emergence and establishment, flowering time, growth and reproduction and competitive ability in these three closely related species. Seeds were planted, the seedlings were then transplanted and individual performance was evaluated with respect to: (1) competition with plant neighbours and (2) resource addition. Senecio inaequidens had higher rates of seedling establishment and a shorter pre-reproductive period. Competition with neighbours had a considerable impact on S. malacitanus, delaying flowering time and reducing growth and reproduction. S. pterophorus showed inefficient seedling establishment compared to the other two species, but performed better in terms of growth and reproduction. The two alien species were markedly more competitive than the native one. However, differences in competitiveness among S. malacitanus and the two aliens varied depending on resource availability. Thus, Senecio inaequidens and S. pterophorus were more affected by competition in subplots with resource addition and by competition in those without addition, respectively. The latter showed a greater capacity to respond to additional resources in competitive environments and, in addition, its reproductive effort was unrelated to habitat conditions. The invasive potential of the alien species was higher than that of the native. This was a result of various biological characteristics and specific interactions between invader and environment, which made the invasiveness of alien species unpredictable.

Competitive interactions among four pest species of earth mites (Acari: Penthaleidae).

PubMed

Umina, P A; Hoffmann, A A

2005-04-01

Earth mites are major winter pests of a variety of crops and pastures in southern Australia. Competition between four earth mite species was investigated using field and shadehouse experiments. The influence of different plant hosts on the frequency and intensity of competitive interactions also were examined. This information is important, because control attempts that eradicate one species of mite could be directly followed by an increase in abundance of another earth mite species. There were strong effects of intraspecific competition on the reproductive rate of species, while interspecific interactions between Halotydeus destructor (Tucker) and Penthaleus species and between the three Penthaleus species also were detected. Competitive abilities were altered on the different plant types. On pasture, the competitive advantage swayed between Penthaleus major (Dugés), H. destructor, and Penthaleus falcatus (Qin & Halliday). Penthaleus sp. x was the strongest competitor in a mixture of wheat, Triticum aestivum (L.), and oats, Avena sativa (L.), whereas on canola, Brassica napus (L.), and bristly ox-tongue, Picris echioides (L.), P. falcatus, and H. destructor were superior competitors. These results suggest that competition is a strong force influencing the abundance of earth mites in the field and that host plant factors are important in shaping the type of interactions. This highlights the importance of identifying mite species when considering control options and suggests that effective control recommendations need to be developed for each individual species.

Approximate kernel competitive learning.

PubMed

Wu, Jian-Sheng; Zheng, Wei-Shi; Lai, Jian-Huang

2015-03-01

Kernel competitive learning has been successfully used to achieve robust clustering. However, kernel competitive learning (KCL) is not scalable for large scale data processing, because (1) it has to calculate and store the full kernel matrix that is too large to be calculated and kept in the memory and (2) it cannot be computed in parallel. In this paper we develop a framework of approximate kernel competitive learning for processing large scale dataset. The proposed framework consists of two parts. First, it derives an approximate kernel competitive learning (AKCL), which learns kernel competitive learning in a subspace via sampling. We provide solid theoretical analysis on why the proposed approximation modelling would work for kernel competitive learning, and furthermore, we show that the computational complexity of AKCL is largely reduced. Second, we propose a pseudo-parallelled approximate kernel competitive learning (PAKCL) based on a set-based kernel competitive learning strategy, which overcomes the obstacle of using parallel programming in kernel competitive learning and significantly accelerates the approximate kernel competitive learning for large scale clustering. The empirical evaluation on publicly available datasets shows that the proposed AKCL and PAKCL can perform comparably as KCL, with a large reduction on computational cost. Also, the proposed methods achieve more effective clustering performance in terms of clustering precision against related approximate clustering approaches. Copyright © 2014 Elsevier Ltd. All rights reserved.

The cost of parallel consolidation into visual working memory.

PubMed

Rideaux, Reuben; Edwards, Mark

2016-01-01

A growing body of evidence indicates that information can be consolidated into visual working memory in parallel. Initially, it was suggested that color information could be consolidated in parallel while orientation was strictly limited to serial consolidation (Liu & Becker, 2013). However, we recently found evidence suggesting that both orientation and motion direction items can be consolidated in parallel, with different levels of accuracy (Rideaux, Apthorp, & Edwards, 2015). Here we examine whether there is a cost associated with parallel consolidation of orientation and direction information by comparing performance, in terms of precision and guess rate, on a target recall task where items are presented either sequentially or simultaneously. The results compellingly indicate that motion direction can be consolidated in parallel, but the evidence for orientation is less conclusive. Further, we find that there is a twofold cost associated with parallel consolidation of direction: Both the probability of failing to consolidate one (or both) item/s increases and the precision at which representations are encoded is reduced. Additionally, we find evidence indicating that the increased consolidation failure may be due to interference between items presented simultaneously, and is moderated by item similarity. These findings suggest that a biased competition model may explain differences in parallel consolidation between features.

Integrating multiple vegetation indices via an artificial neural network model for estimating the leaf chlorophyll content of Spartina alterniflora under interspecies competition.

PubMed

Liu, Pudong; Shi, Runhe; Zhang, Chao; Zeng, Yuyan; Wang, Jiapeng; Tao, Zhu; Gao, Wei

2017-10-31

The invasive species Spartina alterniflora and native species Phragmites australis display a significant co-occurrence zonation pattern and this co-exist region exerts most competitive situations between these two species, competing for the limited space, directly influencing the co-exist distribution in the future. However, these two species have different growth ratios in this area, which increase the difficulty to detect the distribution situation directly by remote sensing. As chlorophyll content is a key indicator of plant growth and physiological status, the objective of this study was to reduce the effect of interspecies competition when estimating Cab content; we evaluated 79 published representative indices to determine the optimal indices for estimating the chlorophyll a and b (Cab) content. After performing a sensitivity analysis for all 79 spectral indices, five spectral indices were selected and integrated using an artificial neural network (ANN) to estimate the Cab content of different competition ratios: the Gitelson ratio green index, the transformed chlorophyll absorption ratio index/optimized soil-adjusted vegetation index, the modified normalized difference vegetation index, the chlorophyll fluorescence index, and the Vogelmann chlorophyll index. The ANN method yielded better results (R 2  = 0.7110 and RMSE = 8.3829 μg cm -2 ) on average than the best single spectral index (R 2  = 0.6319 and RMSE = 9.3535 μg cm -2 ), representing an increase of 10.78% in R 2 and a decrease of 10.38% in RMSE. Our results indicated that integrating multiple vegetation indices with an ANN can alleviate the impact of interspecies competition and achieve higher estimation accuracy than the traditional approach using a single index.

Competitive Dynamics in MSTd: A Mechanism for Robust Heading Perception Based on Optic Flow

PubMed Central

Layton, Oliver W.; Fajen, Brett R.

2016-01-01

Human heading perception based on optic flow is not only accurate, it is also remarkably robust and stable. These qualities are especially apparent when observers move through environments containing other moving objects, which introduce optic flow that is inconsistent with observer self-motion and therefore uninformative about heading direction. Moving objects may also occupy large portions of the visual field and occlude regions of the background optic flow that are most informative about heading perception. The fact that heading perception is biased by no more than a few degrees under such conditions attests to the robustness of the visual system and warrants further investigation. The aim of the present study was to investigate whether recurrent, competitive dynamics among MSTd neurons that serve to reduce uncertainty about heading over time offer a plausible mechanism for capturing the robustness of human heading perception. Simulations of existing heading models that do not contain competitive dynamics yield heading estimates that are far more erratic and unstable than human judgments. We present a dynamical model of primate visual areas V1, MT, and MSTd based on that of Layton, Mingolla, and Browning that is similar to the other models, except that the model includes recurrent interactions among model MSTd neurons. Competitive dynamics stabilize the model’s heading estimate over time, even when a moving object crosses the future path. Soft winner-take-all dynamics enhance units that code a heading direction consistent with the time history and suppress responses to transient changes to the optic flow field. Our findings support recurrent competitive temporal dynamics as a crucial mechanism underlying the robustness and stability of perception of heading. PMID:27341686

Participation motivation and competition anxiety among Korean and non-Korean wheelchair tennis players

PubMed Central

Jeong, Irully; Park, Sunghee

2013-01-01

The purpose of this study was to examine differences in participation motivation and competition anxiety between Korean and non-Korean wheelchair tennis players and to identify relations between participation motivation and competition anxiety in each group. Sixty-six wheel-chair tennis players who participated in the 2013 Korea Open Wheel-chair Tennis Tournament in Seoul completed the Participation Motivation Survey and the Competitive State Anxiety Inventory II. Data were analyzed by a frequency analysis, descriptive statistics, Pearson’s correlation analysis, and independent samples t-test to identify participants’ demographic characteristics, differences in participation motivation, competition anxiety between Korean and non-Korean players, and correlations between participation motivation and competition anxiety in each group. Korean players reported significantly higher motivation in purification compared to non-Korean players, whereas non-Korean players reported significantly higher motivation in enjoyment. In addition, non-Korean players demonstrated higher cognitive anxiety and self-confidence compared to Korean players. Moreover, the physical anxiety of Korean players was negatively correlated with learning, health-fitness, and enjoyment motivation. On the other hand, only self-confidence was significantly related to learning motivation and enjoyment motivation in non-Korean players. Thus, the results presented herein provide evidence for the development of specialized counseling programs that consider the psychological characteristics of Korean wheelchair tennis players. PMID:24409429

Competitive adsorption of heavy metals in soil underlying an infiltration facility installed in an urban area.

PubMed

Hossain, M A; Furumai, H; Nakajima, F

2009-01-01

Accumulation of heavy metals at elevated concentration and potential of considerable amount of the accumulated heavy metals to reach the soil system was observed from earlier studies in soakaways sediments within an infiltration facility in Tokyo, Japan. In order to understand the competitive adsorption behaviour of heavy metals Zn, Ni and Cu in soil, competitive batch adsorption experiments were carried out using single metal and binary metal combinations on soil samples representative of underlying soil and surface soil at the site. Speciation analysis of the adsorbed metals was carried out through BCR sequential extraction method. Among the metals, Cu was not affected by competition while Zn and Ni were affected by competition of coexisting metals. The parameters of fitted 'Freundlich' and 'Langmuir' isotherms indicated more intense competition in underlying soil compared to surface soil for adsorption of Zn and Ni. The speciation of adsorbed metals revealed less selectivity of Zn and Ni to soil organic matter, while dominance of organic bound fraction was observed for Cu, especially in organic rich surface soil. Compared to underlying soil, the surface soil is expected to provide greater adsorption to heavy metals as well as provide greater stability to adsorbed metals, especially for Cu.

Predators Exacerbate Competitive Interactions and Dominance Hierarchies between Two Coral Reef Fishes

PubMed Central

Hall, April; Kingsford, Michael

2016-01-01

Predation and competition are critical processes influencing the ecology of organisms, and can play an integral role in shaping coral reef fish communities. This study compared the relative and interacting effects of competition and predation on two competing species of coral reef fish, Pomacentrus amboinensis and P. moluccensis (Pomacentridae), using a multifactorial experiment. Fish were subjected to the sight and smell of a known predator (Pseudochromis fuscus), the presence of the heterospecific competitor (i.e., P. amboinensis vs. P. moluccensis), or a combination of the two for a period of 19 days. The sub-lethal effects of predator/competitor treatments were compared with controls; a combination of otolith microstructure analysis and observations were used to determine otolith growth patterns and behaviour. We predicted that the stress of competition and/or predation would result in strong sub-lethal impacts, and act synergistically on growth and behavioural patterns. We found strong evidence to support this prediction, but only for P. amboinensis, which suffered reductions in growth in both predator and competitor treatments, with the largest reductions occurring when subjected to both predation and competition concurrently. There was strong evidence of asymmetrical competition between the two damselfish species, with P. moluccensis as the dominant competitor, displaying strong aggressive behaviour towards P. amboinensis. Growth reductions for P. amboinensis in predator/competitor treatments appeared to come about primarily due to increases in shelter seeking behaviour, which significantly reduced the foraging rates of individuals compared with controls. These data highlight the importance of predator/competitor synergisms in influencing key behaviours and demographic parameters for juvenile coral reef fishes. PMID:26992169

The injury profile of Karate World Championships: new rules, less injuries.

PubMed

Arriaza, Rafael; Leyes, Manuel; Zaeimkohan, Hamid; Arriaza, Alvaro

2009-12-01

The aim of this paper is to document the injury rate in high-level modern competitive karate after a change of competition rules was implemented in the year 2000, and to compare it with the injury rate found before the rules were changed. A prospective recording of the injuries resulting from 2,762 matches in three consecutive World Karate Championships (representing 7,425 min of active fighting) was performed, and compared with the results from 2,837 matches from the three last World Karate Championships (representing 7,631 min of active fighting) held before the change of competition rules. In total, 497 injuries were recorded, with an incidence of 0.180 injuries per match or 6.7 per 100 min of active fighting. There were 1,901 male category fights (in which 383 injuries were recorded), and 861 female category fights (in which 114 injuries were recorded). The global injury incidence was almost double with the old rules compared to the one with the new rules [OR 1.99, 95% CI (1.76-2.26); p < 0.00001]. In male category, the risk of injury was higher before the rules were changed [OR 1.81, 95% CI (1.56-2.09); p < 0.00001], and also in female category [OR 2.71; 95% CI (2.64-2.80); p < 0.00001]. The rate of severe injuries was not different before and after the change of rules. The implementation of the new competition rules in competitive karate has been associated with a significant reduction in injury rate, making competition safer for athletes.

Managing an evolution: Deregulation of the electric utility industry

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

Skinner, S.K.

1994-12-31

The author discusses the emerging competitive situation in the electric power industry as deregulation of electric utilities looms on the horizon. The paper supports this change, and the competition it will bring, but urges caution as changes are instituted, and the regulatory bodies decide how and how much to free, and at what rates. The reason for his urge for caution comes from historical experience of other industries, which were smaller and had less direct impact on every American.

A Study of Overhead Rate Behavior at a US Air Force Base in the Context of A-76 Competitions.

DTIC Science & Technology

1999-07-28

was included separately to portray time as an important independent variable. 12 Defense Reform Initiative Report (DoD 1997a), p. 29 . 13 Defense...a threshold of savings that is at least 10 percent of direct personnel costs or $10 million over the performance period. 29 OMB established this...been performing the activity prior to the competition and, 29 The length of the contract is generally considered to be the performance period. Depending

PhysDoc: A Distributed Network of Physics Institutions: Collecting, Indexing, and Searching High Quality Documents by Using Harvest; The Dublin Core Metadata Initiative: Mission, Current Activities, and Future Directions; Information Services for Higher Education: A New Competitive Space; Intellectual Property Conservancies.

ERIC Educational Resources Information Center

Severiens, Thomas; Hohlfeld, Michael; Zimmermann, Kerstin; Hilf, Eberhard R.; von Ossietzky, Carl; Weibel, Stuart L.; Koch, Traugott; Hughes, Carol Ann; Bearman, David

2000-01-01

Includes four articles that discuss a variety to topics, including a distributed network of physics institutions documents called PhysDocs which harvests information from the local Web-servers of professional physics institutions; the Dublin Core metadata initiative; information services for higher education in a competitive environment; and…

Dynamic competitive probabilistic principal components analysis.

PubMed

López-Rubio, Ezequiel; Ortiz-DE-Lazcano-Lobato, Juan Miguel

2009-04-01

We present a new neural model which extends the classical competitive learning (CL) by performing a Probabilistic Principal Components Analysis (PPCA) at each neuron. The model also has the ability to learn the number of basis vectors required to represent the principal directions of each cluster, so it overcomes a drawback of most local PCA models, where the dimensionality of a cluster must be fixed a priori. Experimental results are presented to show the performance of the network with multispectral image data.

Multiplex sequence analysis demonstrates the competitive growth advantage of the A-to-G mutants of clarithromycin-resistant Helicobacter pylori.

PubMed

Wang, G; Rahman, M S; Humayun, M Z; Taylor, D E

1999-03-01

Clarithromycin resistance in Helicobacter pylori is due to point mutation within the 23S rRNA. We examined the growth rates of different types of site-directed mutants and demonstrated quantitatively the competitive growth advantage of A-to-G mutants over other types of mutants by a multiplex sequencing assay. The results provide a rational explanation of why A-to-G mutants are predominantly observed among clarithromycin-resistant clinical isolates.

Multiplex Sequence Analysis Demonstrates the Competitive Growth Advantage of the A-to-G Mutants of Clarithromycin-Resistant Helicobacter pylori

PubMed Central

Wang, Ge; Rahman, M. Sayeedur; Humayun, M. Zafri; Taylor, Diane E.

1999-01-01

Clarithromycin resistance in Helicobacter pylori is due to point mutation within the 23S rRNA. We examined the growth rates of different types of site-directed mutants and demonstrated quantitatively the competitive growth advantage of A-to-G mutants over other types of mutants by a multiplex sequencing assay. The results provide a rational explanation of why A-to-G mutants are predominantly observed among clarithromycin-resistant clinical isolates. PMID:10049289

The FY 1981 Department of Defense Program for Research, Development, and Acquisition.

DTIC Science & Technology

1980-02-01

competitive in world markets . In sum, we see the Soviets entering the decade of the 1980s with a commitment to compete in quality with U.S. weapon systems. A 1...the quantity, the market condition, and our acqui- sition strategy are some of the factors directly affecting competitive statistics. Past source...customer in the market place. In reviewing a proposed Mission Element Need Statement (MENS) we now ask ourselves, "What magnitude of resources we are

Why Sexually Selected Weapons Are Not Ornaments.

PubMed

McCullough, Erin L; Miller, Christine W; Emlen, Douglas J

2016-10-01

The elaboration and diversification of sexually selected weapons remain poorly understood. We argue that progress in this topic has been hindered by a strong bias in sexual selection research, and a tendency for weapons to be conflated with ornaments used in mate choice. Here, we outline how male-male competition and female choice are distinct mechanisms of sexual selection, and why weapons and ornaments are fundamentally different types of traits. We call for research on the factors contributing to weapon divergence, the potential for male-male competition to drive speciation, and the specific use of weapons in the context of direct fights versus displays. Given that weapons are first and foremost fighting structures, biomechanical approaches are an especially promising direction for understanding weapon design. Copyright © 2016 Elsevier Ltd. All rights reserved.

Differential competitive ability between sexes in the dioecious Antennaria dioica (Asteraceae)

PubMed Central

Varga, Sandra; Kytöviita, Minna-Maarit

2012-01-01

Background and Aims Differences in competitive ability between the sexes of dioecious plants are expected as a result of allocation trade-offs associated with sex-differential reproductive costs. However, the available data on competitive ability in dioecious plants are scarce and contradictory. In this study sexual competition was evaluated using the dioecious plant Antennaria dioica in a common garden transplantation experiment. Methods Male and female plants were grown for 3 years either in isolation, or in competition with a plant of the same sex or the opposite sex. Flowering phenology, sexual and asexual reproduction, plant growth, nutrient content and arbuscular mycorrhizal colonization in the roots were assessed. Key Results Our results showed little evidence of sexual differences in competitive ability. Both sexes suffered similarly from competition, and competitive effects were manifested in some traits related to fitness but not in others. Survival was unaffected by competition, but competing plants reduced their vegetative growth and reproductive investment compared with non-competing plants. In addition, differences in sexual competitive ability were observed in relation to flowering frequency, an important life history trait not reported in previous studies. Conclusions The findings indicate that female and male A. dioica plants possess similar intersexual competitive abilities which may be related to the similar costs of reproduction between sexes in this species. Nevertheless, intrasexual competition is higher in females, giving support for asymmetric niche segregation between the sexes. PMID:22887023

Thin film femtosecond laser damage competition

NASA Astrophysics Data System (ADS)

Stolz, Christopher J.; Ristau, Detlev; Turowski, Marcus; Blaschke, Holger

2009-10-01

In order to determine the current status of thin film laser resistance within the private, academic, and government sectors, a damage competition was started at the 2008 Boulder Damage Symposium. This damage competition allows a direct comparison of the current state of the art of high laser resistance coatings since they are tested using the same damage test setup and the same protocol. In 2009 a high reflector coating was selected at a wavelength of 786 nm at normal incidence at a pulse length of 180 femtoseconds. A double blind test assured sample and submitter anonymity so only a summary of the results are presented here. In addition to the laser resistance results, details of deposition processes, coating materials and layer count, and spectral results will also be shared.

BDS thin film damage competition

NASA Astrophysics Data System (ADS)

Stolz, Christopher J.; Thomas, Michael D.; Griffin, Andrew J.

2008-10-01

A laser damage competition was held at the 2008 Boulder Damage Symposium in order to determine the current status of thin film laser resistance within the private, academic, and government sectors. This damage competition allows a direct comparison of the current state-of-the-art of high laser resistance coatings since they are all tested using the same damage test setup and the same protocol. A normal incidence high reflector multilayer coating was selected at a wavelength of 1064 nm. The substrates were provided by the submitters. A double blind test assured sample and submitter anonymity so only a summary of the results are presented here. In addition to the laser resistance results, details of deposition processes, coating materials, and layer count will also be shared.

Growth of ponderosa pine seedlings as affected by air pollution

NASA Astrophysics Data System (ADS)

Momen, B.; Anderson, P. D.; Houpis, J. L. J.; Helms, J. A.

The effect of air pollution on seedling survival and competitive ability is important to natural and artificial regeneration of forest trees. Although biochemical and physiological processes are sensitive indicators of pollution stress, the cumulative effects of air pollutants on seedling vigor and competitive ability may be assessed directly from whole-plant growth characteristics such as diameter, height, and photosynthetic area. A few studies that have examined intraspecific variation in seedling response to air pollution indicate that genotypic differences are important in assessing potential effects of air pollution on forest regeneration. Here, we studied the effects of acid rain (no-rain, pH 5.1 rain, pH 3.0 rain) and ozone (filtered, ambient, twice-ambient) in the field on height, diameter, volume, the height:diameter ratio, maximum needle length, and time to reach maximum needle length in seedlings of three families of ponderosa pine ( Pinus ponderosa Dougl. ex Laws). Seedling diameter, height, volume, and height:diameter ratio related significantly to their pre-treatment values. Twice-ambient ozone decreased seedling diameter compared with ozone-filtered air. A significant family-by-ozone interaction was detected for seedling height, as the height of only one of the three families was decreased by twice-ambient ozone compared with the ambient level. Seedling diameter was larger and the height:diameter ratio was smaller under pH 3.0 rain compared to either the no-rain or the pH 5.1-rain treatment. This suggests greater seedling vigor, perhaps due to a foliar fertilization effect of the pH 3.0 rain.

X-ray computed tomography uncovers root-root interactions: quantifying spatial relationships between interacting root systems in three dimensions.

PubMed

Paya, Alexander M; Silverberg, Jesse L; Padgett, Jennifer; Bauerle, Taryn L

2015-01-01

Research in the field of plant biology has recently demonstrated that inter- and intra-specific interactions belowground can dramatically alter root growth. Our aim was to answer questions related to the effect of inter- vs. intra-specific interactions on the growth and utilization of undisturbed space by fine roots within three dimensions (3D) using micro X-ray computed tomography. To achieve this, Populus tremuloides (quaking aspen) and Picea mariana (black spruce) seedlings were planted into containers as either solitary individuals, or inter-/intra-specific pairs, allowed to grow for 2 months, and 3D metrics developed in order to quantify their use of belowground space. In both aspen and spruce, inter-specific root interactions produced a shift in the vertical distribution of the root system volume, and deepened the average position of root tips when compared to intra-specifically growing seedlings. Inter-specific interactions also increased the minimum distance between root tips belonging to the same root system. There was no effect of belowground interactions on the radial distribution of roots, or the directionality of lateral root growth for either species. In conclusion, we found that significant differences were observed more often when comparing controls (solitary individuals) and paired seedlings (inter- or intra-specific), than when comparing inter- and intra-specifically growing seedlings. This would indicate that competition between neighboring seedlings was more responsible for shifting fine root growth in both species than was neighbor identity. However, significant inter- vs. intra-specific differences were observed, which further emphasizes the importance of biological interactions in competition studies.

Performance Aspects and Physiological Responses in Male Amateur Boxing Competitions: A Brief Review.

PubMed

Slimani, Maamer; Chaabène, Helmi; Davis, Philip; Franchini, Emerson; Cheour, Foued; Chamari, Karim

2017-04-01

Slimani, M, Chaabène, H, Davis, P, Franchini, E, Cheour, F, and Chamari, K. Performance aspects and physiological responses in male amateur boxing competitions: a brief review. J Strength Cond Res 31(4): 1132-1141, 2017-Boxing is one of the most popular striking combat sports in the world. The aim of this review was to present data concerning performance analysis (time-motion and technical-tactical analysis) and physiological responses (i.e., blood lactate concentration [BLC], heart rate, and oxygen consumption) during novice and elite male simulated and official amateur boxing competitions in any age category. The present review shows that boxing competition is a high-intensity intermittent striking combat sport. Typically, the activity-to-rest ratio was higher in elite (18:1) than in novice (9:1) boxers and significant differences were observed between rounds (first round = 16:1, second round = 8:1, and third round = 6:1) in novice boxers. Thus, total stop-time and total stop-frequency increased over subsequent rounds in novice boxers. The technical-tactical aspects in elite and novice boxing bouts were different between rounds and dependent on the match outcome (i.e., winners vs. losers). Particularly, the current review highlights that triple-punch combinations, total combinations, block- and counter-punch combinations, total punches to the head, technical performance effectiveness, and defensive- and offensive-skills effectiveness may have contributed to win in novice and elite boxing competitions. Higher frequencies of technical movements were also observed in elite compared with novice boxers. From a physiological point of view, BLC increased significantly from postround 1 compared with postround 3 in novice boxing match. BLC was also higher in official than in simulated elite boxing matches in senior compared with junior boxers and in medium heavy-weight category compared with light- and medium-weight categories in junior boxing competition. A higher percentage of maximal heart rate (%HRmax) and maximal oxygen uptake (V[Combining Dot Above]O2max) were reported in round 3 compared with rounds 2 and 1 in elite boxing competition. In conclusion, these data are useful for both technical-tactical and physical conditioning sessions. Coaches and fitness trainers are encouraged to adjust their training according to these particular characteristics, specifically in terms of age, participants' level, weight categories, and combat contest type.