bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genitals evolve faster than other traits in Anolis lizards
Authors: Klaczko J. , Ingram T. , Losos J. 
Published: January 2015

AbstractMale genitalia are thought to be particularly rapidly evolving morphological structures, but there have been few quantitative interspecific comparisons between the evolutionary rates of genital and nongenital traits. We characterize the morphology of hemipenes in 25 Caribbean Anolis lizard species, and compare rates of hemipenial evolution to those of traits related to ecology or visual signaling. Using phylogenetically based comparisons of rates of evolutionary divergence, we show that genital traits evolve more rapidly than nongenital traits in anoles.
Stable isotopes in a southern European crossbill population indicate restricted movement between regions with different pine species
Authors: Arizaga J. , Alonso D. , Edelaar P. 
Published: January 2015

AbstractThe adaptation of irruptive birds to breed where they find abundant food allows them to be highly mobile and ubiquitous and opens a debate on the ecological and evolutionary impact of this behavior. Using δ2H analyses, our aim here was to test whether the density fluctuation in a southern European crossbill population is caused by movements of irruptive northern European crossbills or of crossbills from nearby. Sampling was carried out in the western Pyrenees during four consecutive breeding seasons (2009–2012). During these four years, 2009 was a year with a much higher number of captures per day and this coincided with an invasion of crossbills in northern Europe. Only two out of 160 crossbills showed clear isotopic signatures of a northern European origin (and both were caught in 2009). Moreover, in 2009, we recaptured a bird ringed in The Netherlands. Otherwise, we found no differences among years in δ2H and no significant effect of wing length (indicative of a northern origin) or residency status (long‐term recaptures vs. non‐recaptures) on δ2H. Wing length also did not vary among these four years. Therefore, our results suggest that annual variation in local crossbill abundances is not only due to the movements of northern irruptive birds, but also to a large part due to the influx and local reproduction of individuals of Iberian origin. The lack of annual variation in isotopic signatures and similarity with values from a nearby mountain area with the same food resource (the pine Pinus sylvestris) suggests that movements are primarily between areas with the same type of resource. Thus, our results support recent morphological and genetic studies that indicate that crossbill populations within Iberia are not structured geographically but by resource use.
Is the Sum Greater than the Parts? The Terms of Civil War Peace Agreements and the Commitment Problem Revisited
Authors: Joshi Madhav , Quinn J. Michael 
Published: January 2015

The dominant theoretical approaches to civil war negotiations in the field of political science have sought to explain both the scarcity and high failure rates of negotiated agreements in civil conflicts. This historical pattern, however, has fundamentally changed in the last two decades as changes in international norms and laws, as well as the increased prevalence and competence of peacebuilding professionals, now require conflict actors to have a greater commitment toward negotiations and the enforcement of agreements. While actors in interstate wars seek to avoid accountability, civil war actors seem to embrace the opportunities that these new dynamics create to achieve broad‐based reforms across numerous areas of policy and government. The result, we suggest, is that stakeholders evaluate agreements based on their potential to accomplish an array of sociopolitical objectives. In addition, for strategic and practical reasons, they perceive that those agreements that include more reforms across multiple policy sectors will have the greatest potential.Our examination of nearly two hundred agreements found evidence that the peacemaking potential of a negotiated agreement between civil war adversaries is greatly enhanced when reforms are pursued across many different policy domains. Conversely, our analysis suggests that the greater the number of policy areas left untouched by a peace agreement, the more likely the stakeholders will be to follow that agreement with additional negotiations to enhance that agreement, or, alternatively, the more likely that violence will resume.
Preferential allocation, physio‐evolutionary feedbacks, and the stability and environmental patterns of mutualism between plants and their root symbionts
Authors: Bever James D. 
Published: January 2015

Summary

The common occurrence of mutualistic interactions between plants and root symbionts is problematic. As the delivery of benefit to hosts involves costs to symbionts, symbionts that provide reduced benefit to their host are expected to increase in frequency. Plants have been shown to allocate preferentially to the most efficient symbiont and this preferential allocation may stabilize the mutualism.

I construct a general model of the interactive feedbacks of host preferential allocation and the dynamics of root symbiont populations to evaluate the stability of nutritional mutualisms.

Preferential allocation can promote the evolution of mutualism even when the cost to the symbiont is very large. Moreover, the physiological plasticity of preferential allocation likely leads to coexistence of beneficial and nonbeneficial symbionts. For arbuscular mycorrhizal fungi, which facilitate plant uptake of phosphorus (P), the model predicts greater P transfer from these fungi per unit carbon invested with decreasing concentrations of soil P and with increasing concentrations of atmospheric CO2, patterns that have been observed in laboratory and field studies.

This framework connects physiological plasticity in plant allocation to population processes that determine mutualism stability and, as such, represents a significant step in understanding the stability and environmental patterns in mutualism.
Capillary‐Venous Malformation in the Upper Limb
Authors: Uihlein Lily Changchien , Liang Marilyn G. , Fishman Steven J. , Alomari Ahmad I. , Mulliken John B. 
Published: January 2015

AbstractWe present a group of patients with regional capillary malformations of the upper limbs and few additional findings other than prominent veins. We believe that this entity is the upper extremity equivalent of capillary‐venous malformation of the lower limb and, likewise, belongs at the minor end of the spectrum of vascular disorders with overgrowth.
The Role of Child Characteristics and Peer Experiences in the Development of Peer Cooperation
Authors: Endedijk Hinke M. , Cillessen Antonius H. N. , Cox Ralf F. A. , Bekkering Harold , Hunnius Sabine 
Published: January 2015

AbstractCooperation with peers is challenging for young children, and there are large individual differences in the development of cooperation. The roles of child characteristics and peer experiences for peer interaction during free play have been studied extensively, but it is unclear which factors predict young children's successful cooperation at different points in development. In this study, 2‐, 3‐, and 4‐year‐old children were observed during a peer cooperation task. Both their interactive behavior and cooperation success were examined, and the association of these variables with child characteristics and peer experiences was explored. Results showed that successful peer cooperation increased with age. Moreover, early individual differences in peer cooperation were related to temperamental characteristics, and, among older children, the rate of cooperation was related to prior peer experience.
Whole-Body Cryotherapy’s Enhancement of Acute Recovery of Running Performance in Well-Trained Athletes
Authors: Krüger Malte , de Mareés Markus , Dittmar Karl-Heinrich , Sperlich Billy , Mester Joachim 
Published: January 2015

Purpose:To examine the effects of a whole-body cryotherapy (WBC) protocol (3 min at –110°C) on acute recovery and key variables of endurance performance during high-intensity intermittent exercise in a thermoneutral environment.Methods:Eleven endurance athletes were tested twice in a randomized crossover design in which 5 × 5 min of high-intensity running (HIR) were followed by 1 h of passive rest at ~22°C, including either 3 min of whole-body exposure to –110°C (WBC) or a placebo intervention of 3 min walking (PBO). A ramp-test protocol was performed before HIR (R1) and after the 1-h recovery period (R2). Time to exhaustion (tlim) was measured along with alterations in oxygen content of the vastus lateralis (TSI), oxygen consumption (VO2), capillary blood lactate, heart rate (HR), and rating of perceived exertion (RPE) during submaximal and maximal running.Results:The difference in tlim between R1 and R2 was lower in WBC than in PBO (P < .05, effect size d = 1.13). During R2, TSI was higher in WBC during submaximal and maximal running (P < .01, d = 0.68−1.01). In addition, VO2, HR, and RPE were lower at submaximal level of R2 after WBC than in PBO (P = .04 to <.01, d = 0.23−0.83).Conclusion:WBC improves acute recovery during high-intensity intermittent exercise in thermoneutral conditions. The improvements might be induced by enhanced oxygenation of the working muscles, as well as a reduction in cardiovascular strain and increased work economy at submaximal intensities.
Gender-Specific Activity Demands Experienced During Semiprofessional Basketball Game Play
Authors: Scanlan Aaron T. , Dascombe Ben J. , Kidcaff Andrew P. , Peucker Jessica L. , Dalbo Vincent J. 
Published: January 2015

Purpose:To compare game activity demands between female and male semiprofessional basketball players.Methods:Female (n = 12) and male (n = 12) semiprofessional basketball players were monitored across 3 competitive games. Time–motion-analysis procedures quantified player activity into predefined movement categories across backcourt (BC) and frontcourt (FC) positions. Activity frequencies, durations, and distances were calculated relative to live playing time (min). Work:rest ratios were also calculated using the video data. Game activity was compared between genders for each playing position and all players.Results:Female players performed at greater running work-rates than male players (45.7 ± 1.4 vs. 42.1 ± 1.7 m/min, P = .05), while male players performed more dribbling than female players (2.5 ± 0.3 vs. 3.0 ± 0.2 s/min; 8.4 ± 0.3 vs. 9.7 ± 0.7 m/min, P = .05). Positional analyses revealed that female BC players performed more low-intensity shuffling (P = .04) and jumping (P = .05), as well as longer (P = .04) jogging durations, than male BC players. Female FC players executed more upper-body activity (P = .03) and larger work:rest ratios (P < .001) than male FC players. No significant gender differences were observed in the overall intermittent demands, distance traveled, high-intensity shuffling activity, and sprinting requirements during game play.Conclusions:These findings indicate that gender-specific running and dribbling differences might exist in semiprofessional basketball. Furthermore, position-specific variations between female and male basketball players should be considered. These data may prove useful in the development of gender-specific conditioning plans relative to playing position in basketball.
Athletes’ Use of Mental Skills During Sport Injury Rehabilitation
Authors: Arvinen-Barrow Monna , Clement Damien , Hamson-Utley Jennifer J. , Zakrajsek Rebecca A. , Lee Sae-Mi , Kamphoff Cindra , Lintunen Taru , Hemmings Brian , Martin Scott B. 
Published: January 2015

Context:Existing theoretical frameworks and empirical research support the applicability and usefulness of integrating mental skills throughout sport injury rehabilitation.Objective:To determine what, if any, mental skills athletes use during injury rehabilitation, and by who these skills were taught. Cross-cultural differences were also examined.Design:Cross-sectional design.Setting:College athletes from 5 universities in the United States and a mixture of collegiate, professional, and recreational club athletes from the United Kingdom and Finland were recruited for this study.Participants:A total of 1283 athletes from the United States, United Kingdom, and Finland, who participated in diverse sports at varying competitive levels took part in this study.Main Outcome Measures:As part of a larger study on athletes’ expectations of injury rehabilitation, participants were asked a series of open-ended and closed-ended questions concerning their use of mental skills during injury rehabilitation.Results:Over half (64.0%) of the sample reported previous experience with athletic training, while 27.0% indicated that they used mental skills during injury rehabilitation. The top 3 mental skills reported were goal setting, positive self-talk/positive thoughts, and imagery. Of those athletes that used mental skills, 71.6% indicated that they felt mental skills helped them to rehabilitate faster. A greater proportion of athletes from the United States (33.4%) reported that they used mental skills during rehabilitation compared with athletes from the United Kingdom (23.4%) and Finland (20.3%). A small portion (27.6%) of the participants indicated that their sports medicine professional had taught them how to use mental skills; only 3% were taught mental skills by a sport psychologist.Conclusions:The low number of athletes who reported using mental skills during rehabilitation is discouraging, but not surprising given research findings that mental skills are underutilized by injured athletes in the 3 countries examined. More effort should be focused on educating and training athletes, coaches, and sports medicine professionals on the effectiveness of mental training in the injury rehabilitation context.
Effect of Prophylactic Ankle-Brace Use During a High School Competitive Basketball Season on Dynamic Postural Control
Authors: Crockett Nathan J. , Sandrey Michelle A. 
Published: January 2015

Context:Few studies have evaluated the long-term effects of prophylactic ankle-brace use during a sport season.Objective:To determine the effects of prophylactic ankle-brace use during a high school basketball season on dynamic postural control and functional tests.Design:Prospective repeated-measures design.Setting:High school athletic facility.Participants:21 healthy high school basketball athletes (13 girls, 8 boys).Interventions:The order of testing was randomized using the Star Excursion Balance Test (SEBT) for posteromedial (PM), medial (M), and anteromedial (AM) directions and 3 functional tests (FT) consisting of the single-leg crossover hop, single-leg vertical jump, and the single-leg 6-m hop for time at pre-, mid-, and postseason. After pretesting, the ankle brace was worn on both limbs during the entire 16-wk competitive basketball season.Main Outcome Measures:SEBT for PM, M, and AM and 3 single-leg FTs.Results:Dynamic postural control using the SEBT and the 3 FTs improved over time, notably from pretest to posttest. The left limb was different from the right limb during the single-leg vertical jump. Effect sizes were large for pretest to posttest for the 3 SEBT directions and 2 of the 3 FTs.Conclusions:The 16-wk basketball prophylactic ankle-brace intervention significantly improved dynamic postural control and single-limb FTs over time.
Shoulder-Muscle Activation in Individuals With Previous Shoulder Injuries
Authors: Muething Alyssa , Acocello Shellie , Pritchard Kimberly A. , Brockmeier Stephen F. , Saliba Susan A. , Hart Joseph M. 
Published: January 2015

Context:Understanding how muscles activate in a population with a previous glenohumeral-joint (GH) injury may help clinicians understand how to build a conservative treatment plan to strengthen or activate the specific muscles in an attempt to reduce recurrent shoulder injury and development of GH laxity.Objective:To investigate muscle-activation differences between the previously injured limb of individuals with a history of GH-joint injury and healthy matched controls during functional isometric contractions.Design:Case control.Setting:University research laboratory.Participants:17 individuals (8 women, 9 men; age 22.3 ± 2.6 y, height 172.4 ± 8.8 cm, mass 75.4 ± 16.5 kg) with previous unilateral shoulder pain and 17 (8 women, 9 men; age 22.9 ± 3.9 y, height 170.9 ± 11.3 cm, mass 73.6 ± 22.9 kg) with no history of shoulder pain or injury.Intervention(s):Diagnostic ultrasound measurements of the supraspinatus were completed in both resting and contracted states to assess changes in muscle thickness. Manual muscle tests (anterior deltoid, upper trapezius, infraspinatus, lower trapezius, serratus anterior) and functional isometric contractions (forward flexion, scaption, abduction) were measured using electromyography.Main Outcome Measures:Peak, normalized activation of each muscle and supraspinatus thickness activation ratio were compared between groups and bilaterally within groups using separate ANOVAs.Results:The anterior deltoid was significantly less activated during all functional isometric tasks in previously injured subjects than in healthy subjects (P = .024). In previously injured subjects, the involved limb-lower trapezius was significantly less activated during scaption and abduction tasks than the contralateral side (P = .022 and P = .031, respectively).Conclusions:There were decreases in muscle activation in the anterior deltoid between previously injured and healthy people, as well as in the lower trapezius, in previously injured subjects. Understanding the source of muscle-activation deficits can help clinicians focus rehabilitation exercises on specific muscles.
Acute Effects of Stretching on Passive Properties of Human Gastrocnemius Muscle–Tendon Unit: Analysis of Differences Between Hold-Relax and Static Stretching
Authors: Nakamura Masatoshi , Ikezoe Tome , Tokugawa Takahiro , Ichihashi Noriaki 
Published: January 2015

Context:Hold–relax stretching (HRS) and static stretching (SS) are commonly used to increase joint range of motion (ROM) and decrease muscle stiffness. However, whether there are differences between acute effects of HRS and SS on end ROM, passive torque, and muscle stiffness is unclear. In addition, any differences between the mechanisms by which HRS and SS lead to an increase in end ROM are unclear.Objective:To compare the acute effects of HRS and SS on the passive properties of the gastrocnemius muscle–tendon unit (MTU), end ROM, passive torque, and muscle stiffness in vivo and to investigate the factors involved in increasing end ROM.Design:Crossover experimental design.Participants:30 healthy men (21.7 ± 1.2 y) with no history of neuromuscular disease or musculoskeletal injury involving the lower limbs.Intervention:Both HRS and SS of 30 s were repeated 4 times, lasting a total of 2 min.Main Outcome Measures:End ROM, passive torque, and muscle stiffness were measured during passive ankle dorsiflexion using a dynamometer and ultrasonography before and immediately after HRS and SS.Results:The results showed that end ROM and passive torque at end ROM significantly increased immediately after both HRS and SS, whereas muscle stiffness significantly decreased. In addition, the percentage change in passive torque at end ROM on use of the HRS technique was significantly higher than that after use of the SS technique. However, the percentage change in muscle stiffness after SS was significantly higher than that with HRS.Conclusion:These results suggest that both HRS and SS can effectively decrease muscle stiffness of the gastrocnemius MTU and that HRS induces a change in the passive torque at end ROM—ie, sensory perception—rather than changing muscle stiffness.
Strategic Information Disclosure to People with Multiple Alternatives
Authors: Azaria Amos , Rabinovich Zinovi , Goldman Claudia V. , Kraus Sarit 
Published: January 2015

In this article, we study automated agents that are designed to encourage humans to take some actions over others by strategically disclosing key pieces of information. To this end, we utilize the framework of persuasion games—a branch of game theory that deals with asymmetric interactions where one player (Sender) possesses more information about the world, but it is only the other player (Receiver) who can take an action. In particular, we use an extended persuasion model, where the Sender’s information is imperfect and the Receiver has more than two alternative actions available. We design a computational algorithm that, from the Sender’s standpoint, calculates the optimal information disclosure rule. The algorithm is parameterized by the Receiver’s decision model (i.e., what choice he will make based on the information disclosed by the Sender) and can be retuned accordingly.We then provide an extensive experimental study of the algorithm’s performance in interactions with human Receivers. First, we consider a fully rational (in the Bayesian sense) Receiver decision model and experimentally show the efficacy of the resulting Sender’s solution in a routing domain. Despite the discrepancy in the Sender’s and the Receiver’s utilities from each of the Receiver’s choices, our Sender agent successfully persuaded human Receivers to select an option more beneficial for the agent. Dropping the Receiver’s rationality assumption, we introduce a machine learning procedure that generates a more realistic human Receiver model. We then show its significant benefit to the Sender solution by repeating our routing experiment. To complete our study, we introduce a second (supply--demand) experimental domain and, by contrasting it with the routing domain, obtain general guidelines for a Sender on how to construct a Receiver model.
Smartphones, Studio-Based Learning, and Scaffolding
Authors: Reardon Susan , Tangney Brendan 
Published: January 2015

This article describes how smartphones, studio-based learning, and extensive scaffolding were used in combination in the teaching of a freshman Introduction to Programming course. To reduce cognitive overload, a phased approach was followed in introducing programming concepts and development environments, beginning with the visual programming environment Scratch and culminating with Java development for Android smartphones. Studio-based learning, a pedagogical approach long established in the fields of architecture and design education, was used as the basis for a collaborative social constructivist—and constructionist—approach to learning. Smartphones offered students the potential to develop applications for a context that is both immediate and clearly relevant to the ways in which they utilize and interact with technology.
The research was carried out over three full academic years and included 53 student participants. An exploratory case study methodology was used to investigate the efficacy of the approach in helping to overcome the barriers faced by novice programmers. The findings indicate that the approach has merit. The students were motivated and engaged by the learning experience and were able to develop sophisticated applications that incorporated images, sound, arrays, and event handling. There is evidence that aspects of the studio-based learning approach, such as the scope that it gave students to innovate and the open feedback during student presentations, provided a learning environment that was motivating. Overall, the combination of smartphones, studio-based learning, and appropriate scaffolding offers an effective way to teach introductory programming courses.