WorldWideScience

Sample records for previously hypothesized vicariant

  1. Explaining infant feeding: The role of previous personal and vicarious experience on attitudes, subjective norms, self-efficacy, and breastfeeding outcomes.

    Science.gov (United States)

    Bartle, Naomi C; Harvey, Kate

    2017-11-01

    Breastfeeding confers important health benefits to both infants and their mothers, but rates are low in the United Kingdom and other developed countries despite widespread promotion. This study examined the relationships between personal and vicarious experience of infant feeding, self-efficacy, the theory of planned behaviour variables of attitudes and subjective norm, and the likelihood of breastfeeding at 6-8 weeks post-natally. A prospective questionnaire study of both first-time mothers (n = 77) and experienced breastfeeders (n = 72) recruited at an antenatal clinic in South East England. Participants completed a questionnaire at 32 weeks pregnant assessing personal and vicarious experience of infant feeding (breastfeeding, formula-feeding, and maternal grandmother's experience of breastfeeding), perceived control, self-efficacy, intentions, attitudes (to breastfeeding and formula-feeding), and subjective norm. Infant feeding behaviour was recorded at 6-8 weeks post-natally. Multiple linear regression modelled the influence of vicarious experience on attitudes, subjective norm, and self-efficacy (but not perceived control) and modelled the influence of attitude, subjective norm, self-efficacy, and past experience on intentions to breastfeed. Logistic regression modelled the likelihood of breastfeeding at 6-8 weeks. Previous experience (particularly personal experience of breastfeeding) explained a significant amount of variance in attitudes, subjective norm, and self-efficacy. Intentions to breastfeed were predicted by subjective norm and attitude to formula-feeding and, in experienced mothers, self-efficacy. Breastfeeding at 6 weeks was predicted by intentions and vicarious experience of formula-feeding. Vicarious experience, particularly of formula-feeding, has been shown to influence the behaviour of first-time and experienced mothers both directly and indirectly via attitudes and subjective norm. Interventions that reduce exposure to formula

  2. Vicarious shame

    NARCIS (Netherlands)

    Welten, S.C.M.; Zeelenberg, M.; Breugelmans, S.M.

    2012-01-01

    We examined an account of vicarious shame that explains how people can experience a self-conscious emotion for the behaviour of another person. Two divergent processes have been put forward to explain how another's behaviour links to the self. The group-based emotion account explains vicarious shame

  3. Concern for Others Leads to Vicarious Optimism.

    Science.gov (United States)

    Kappes, Andreas; Faber, Nadira S; Kahane, Guy; Savulescu, Julian; Crockett, Molly J

    2018-03-01

    An optimistic learning bias leads people to update their beliefs in response to better-than-expected good news but neglect worse-than-expected bad news. Because evidence suggests that this bias arises from self-concern, we hypothesized that a similar bias may affect beliefs about other people's futures, to the extent that people care about others. Here, we demonstrated the phenomenon of vicarious optimism and showed that it arises from concern for others. Participants predicted the likelihood of unpleasant future events that could happen to either themselves or others. In addition to showing an optimistic learning bias for events affecting themselves, people showed vicarious optimism when learning about events affecting friends and strangers. Vicarious optimism for strangers correlated with generosity toward strangers, and experimentally increasing concern for strangers amplified vicarious optimism for them. These findings suggest that concern for others can bias beliefs about their future welfare and that optimism in learning is not restricted to oneself.

  4. Music evokes vicarious emotions in listeners

    Science.gov (United States)

    Kawakami, Ai; Furukawa, Kiyoshi; Okanoya, Kazuo

    2014-01-01

    Why do we listen to sad music? We seek to answer this question using a psychological approach. It is possible to distinguish perceived emotions from those that are experienced. Therefore, we hypothesized that, although sad music is perceived as sad, listeners actually feel (experience) pleasant emotions concurrent with sadness. This hypothesis was supported, which led us to question whether sadness in the context of art is truly an unpleasant emotion. While experiencing sadness may be unpleasant, it may also be somewhat pleasant when experienced in the context of art, for example, when listening to sad music. We consider musically evoked emotion vicarious, as we are not threatened when we experience it, in the way that we can be during the course of experiencing emotion in daily life. When we listen to sad music, we experience vicarious sadness. In this review, we propose two sides to sadness by suggesting vicarious emotion. PMID:24910621

  5. Concern for others leads to vicarious optimism

    OpenAIRE

    Kappes, A.; Faber, N. S.; Kahane, G.; Savulescu, J.; Crockett, M. J.

    2018-01-01

    An optimistic learning bias leads people to update their beliefs in response to better-than-expected good news but neglect worse-than-expected bad news. Because evidence suggests that this bias arises from self-concern, we hypothesized that a similar bias may affect beliefs about other people’s futures, to the extent that people care about others. Here, we demonstrated the phenomenon of vicarious optimism and showed that it arises from concern for others. Participants predicted the likelihood...

  6. Unveiling vicariant methodologies in vicariance biogeography : not anything goes

    NARCIS (Netherlands)

    Veller, Marco Gerardus Petrus van

    2000-01-01

    In vicariance biogeography, the present distribution of species over areas is explained with different historical processes. Vicariance is one of these processes and involves speciation by the formation of isolating barriers between areas. By assuming this process, a scenario for the history of

  7. Computer Support for Vicarious Learning.

    Science.gov (United States)

    Monthienvichienchai, Rachada; Sasse, M. Angela

    This paper investigates how computer support for vicarious learning can be implemented by taking a principled approach to selecting and combining different media to capture educational dialogues. The main goal is to create vicarious learning materials of appropriate pedagogic content and production quality, and at the same time minimize the…

  8. Burnout, vicarious traumatization and its prevention.

    Science.gov (United States)

    Pross, Christian

    2006-01-01

    Previous studies on burnout and vicarious traumatization are reviewed and summarized with a list of signs and symptoms. From the author's own observations two histories of caregivers working with torture survivors are described which exemplify the risk,implications and consequences of secondary trauma. Contributing factors in the social and political framework in which caregivers operate are analyzed and possible means of prevention suggested, particularly focussing on the conflict of roles when providing evaluations on trauma victims for health and immigration authorities. Caregivers working with victims of violence carry a high risk of suffering from burnout and vicarious traumatization unless preventive factors are considered such as: self care, solid professional training in psychotherapy, therapeutic self-awareness, regular self-examination by collegial and external supervision, limiting caseload, continuing professional education and learning about new concepts in trauma, occasional research sabbaticals, keeping a balance between empathy and a proper professional distance to clients, protecting oneself against being mislead by clients with fictitious PTSD. An institutional setting should be provided in which the roles of therapists and evaluators are separated. Important factors for burnout and vicarious traumatization are the lack of social recognition for caregivers and the financial and legal outsider status of many centers. Therefore politicians and social insurance carriers should be urged to integrate facilities for traumatized refugees into the general health care system and centers should work on more alliances with the medical mainstream and academic medicine.

  9. ITSSOIN Hypotheses

    NARCIS (Netherlands)

    Anheier, H.K.; Krlev, G.; Preuss, S.; Mildenberger, G.; Bekkers, R.H.F.P.; Brink Lund, A.

    2014-01-01

    This report brings together findings from the first ITSSOIN project working steps to formulate empirically testable hypotheses on the impact of the third sector and social innovation – in particular regarding the role of the third sector in generating social innovation but also with reference to

  10. Thomas Vicary, barber-surgeon.

    Science.gov (United States)

    Thomas, Duncan P

    2006-05-01

    An Act of Parliament in 1540 uniting the barbers and surgeons to form the Barber-Surgeons' Company represented an important foundation stone towards better surgery in England. Thomas Vicary, who played a pivotal role in promoting this union, was a leading surgeon in London in the middle of the 16th century. While Vicary made no direct contribution to surgical knowledge, he should be remembered primarily as one who contributed much towards the early organization and teaching of surgery and to the consequent benefits that flowed from this improvement.

  11. Neural signals of vicarious extinction learning.

    Science.gov (United States)

    Golkar, Armita; Haaker, Jan; Selbing, Ida; Olsson, Andreas

    2016-10-01

    Social transmission of both threat and safety is ubiquitous, but little is known about the neural circuitry underlying vicarious safety learning. This is surprising given that these processes are critical to flexibly adapt to a changeable environment. To address how the expression of previously learned fears can be modified by the transmission of social information, two conditioned stimuli (CS + s) were paired with shock and the third was not. During extinction, we held constant the amount of direct, non-reinforced, exposure to the CSs (i.e. direct extinction), and critically varied whether another individual-acting as a demonstrator-experienced safety (CS + vic safety) or aversive reinforcement (CS + vic reinf). During extinction, ventromedial prefrontal cortex (vmPFC) responses to the CS + vic reinf increased but decreased to the CS + vic safety This pattern of vmPFC activity was reversed during a subsequent fear reinstatement test, suggesting a temporal shift in the involvement of the vmPFC. Moreover, only the CS + vic reinf association recovered. Our data suggest that vicarious extinction prevents the return of conditioned fear responses, and that this efficacy is reflected by diminished vmPFC involvement during extinction learning. The present findings may have important implications for understanding how social information influences the persistence of fear memories in individuals suffering from emotional disorders. © The Author (2016). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  12. Still to Learn from Vicarious Learning

    Science.gov (United States)

    Mayes, J. T.

    2015-01-01

    The term "vicarious learning" was introduced in the 1960s by Bandura, who demonstrated how learning can occur through observing the behaviour of others. Such social learning is effective without the need for the observer to experience feedback directly. More than twenty years later a series of studies on vicarious learning was undertaken…

  13. Other people as means to a safe end: vicarious extinction blocks the return of learned fear.

    Science.gov (United States)

    Golkar, Armita; Selbing, Ida; Flygare, Oskar; Ohman, Arne; Olsson, Andreas

    2013-11-01

    Information about what is dangerous and safe in the environment is often transferred from other individuals through social forms of learning, such as observation. Past research has focused on the observational, or vicarious, acquisition of fears, but little is known about how social information can promote safety learning. To address this issue, we studied the effects of vicarious-extinction learning on the recovery of conditioned fear. Compared with a standard extinction procedure, vicarious extinction promoted better extinction and effectively blocked the return of previously learned fear. We confirmed that these effects could not be attributed to the presence of a learning model per se but were specifically driven by the model's experience of safety. Our results confirm that vicarious and direct emotional learning share important characteristics but that social-safety information promotes superior down-regulation of learned fear. These findings have implications for emotional learning, social-affective processes, and clinical practice.

  14. Vicarious learning and the development of fears in childhood.

    Science.gov (United States)

    Askew, Chris; Field, Andy P

    2007-11-01

    Vicarious learning has long been assumed to be an indirect pathway to fear; however, there is only retrospective evidence that children acquire fears in this way. In two experiments, children (aged 7-9 years) were exposed to pictures of novel animals paired with pictures of either scared, happy or no facial expressions to see the impact on their fear cognitions and avoidance behavior about the animals. In Experiment 1, directly (self-report) and indirectly measured (affective priming) fear attitudes towards the animals changed congruent with the facial expressions with which these were paired. The indirectly measured fear beliefs persisted up to 3 months. Experiment 2 showed that children took significantly longer to approach a box they believed to contain an animal they had previously seen paired with scared faces. These results support theories of fear acquisition that suppose that vicarious learning affects cognitive and behavioral fear emotion, and suggest possibilities for interventions to weaken fear acquired in this way.

  15. Vicarious extinction learning during reconsolidation neutralizes fear memory.

    Science.gov (United States)

    Golkar, Armita; Tjaden, Cathelijn; Kindt, Merel

    2017-05-01

    Previous studies have suggested that fear memories can be updated when recalled, a process referred to as reconsolidation. Given the beneficial effects of model-based safety learning (i.e. vicarious extinction) in preventing the recovery of short-term fear memory, we examined whether consolidated long-term fear memories could be updated with safety learning accomplished through vicarious extinction learning initiated within the reconsolidation time-window. We assessed this in a final sample of 19 participants that underwent a three-day within-subject fear-conditioning design, using fear-potentiated startle as our primary index of fear learning. On day 1, two fear-relevant stimuli (reinforced CSs) were paired with shock (US) and a third stimulus served as a control (CS). On day 2, one of the two previously reinforced stimuli (the reminded CS) was presented once in order to reactivate the fear memory 10 min before vicarious extinction training was initiated for all CSs. The recovery of the fear memory was tested 24 h later. Vicarious extinction training conducted within the reconsolidation time window specifically prevented the recovery of the reactivated fear memory (p = 0.03), while leaving fear-potentiated startle responses to the non-reactivated cue intact (p = 0.62). These findings are relevant to both basic and clinical research, suggesting that a safe, non-invasive model-based exposure technique has the potential to enhance the efficiency and durability of anxiolytic therapies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Vicarious learning: a review of the literature.

    Science.gov (United States)

    Roberts, Debbie

    2010-01-01

    Experiential learning theory stresses the primacy of personal experience and the literature suggests that direct clinical experience is required in order for learning to take place. However, raw or first hand experience may not be the only mechanisms by which students engage in experiential learning. There is a growing body of literature within higher education which suggests that students are able to use another's experience to learn: vicarious learning. This literature review aims to outline vicarious learning within a nursing context. Many of the studies regarding vicarious learning are situated within Higher Education in general, however, within the United States these relate more specifically to nursing students. The literature indicates the increasing global interest in this area. This paper reveals that whilst the literature offers a number of examples illustrating how vicarious learning takes place, opinion on the role of the lecturer is divided and requires further exploration and clarification. The implications for nurse education are discussed.

  17. A comparison of positive vicarious learning and verbal information for reducing vicariously learned fear.

    Science.gov (United States)

    Reynolds, Gemma; Wasely, David; Dunne, Güler; Askew, Chris

    2017-10-19

    Research with children has demonstrated that both positive vicarious learning (modelling) and positive verbal information can reduce children's acquired fear responses for a particular stimulus. However, this fear reduction appears to be more effective when the intervention pathway matches the initial fear learning pathway. That is, positive verbal information is a more effective intervention than positive modelling when fear is originally acquired via negative verbal information. Research has yet to explore whether fear reduction pathways are also important for fears acquired via vicarious learning. To test this, an experiment compared the effectiveness of positive verbal information and positive vicarious learning interventions for reducing vicariously acquired fears in children (7-9 years). Both vicarious and informational fear reduction interventions were found to be equally effective at reducing vicariously acquired fears, suggesting that acquisition and intervention pathways do not need to match for successful fear reduction. This has significant implications for parents and those working with children because it suggests that providing children with positive information or positive vicarious learning immediately after a negative modelling event may prevent more serious fears developing.

  18. Differential influence of social versus isolate housing on vicarious fear learning in adolescent mice.

    Science.gov (United States)

    Panksepp, Jules B; Lahvis, Garet P

    2016-04-01

    Laboratory rodents can adopt the pain or fear of nearby conspecifics. This phenotype conceptually lies within the domain of empathy, a bio-psycho-social process through which individuals come to share each other's emotion. Using a model of cue-conditioned fear, we show here that the expression of vicarious fear varies with respect to whether mice are raised socially or in solitude during adolescence. The impact of the adolescent housing environment was selective: (a) vicarious fear was more influenced than directly acquired fear, (b) "long-term" (24-h postconditioning) vicarious fear memories were stronger than "short-term" (15-min postconditioning) memories in socially reared mice whereas the opposite was true for isolate mice, and (c) females were more fearful than males. Housing differences during adolescence did not alter the general mobility of mice or their vocal response to receiving the unconditioned stimulus. Previous work with this mouse model underscored a genetic influence on vicarious fear learning, and the present study complements these findings by elucidating an interaction between the adolescent social environment and vicarious experience. Collectively, these findings are relevant to developing models of empathy amenable to mechanistic exploitation in the laboratory. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  19. Vicarious Reinforcement In Rhesus Macaques (Macaca mulatta

    Directory of Open Access Journals (Sweden)

    Steve W. C. Chang

    2011-03-01

    Full Text Available What happens to others profoundly influences our own behavior. Such other-regarding outcomes can drive observational learning, as well as motivate cooperation, charity, empathy, and even spite. Vicarious reinforcement may serve as one of the critical mechanisms mediating the influence of other-regarding outcomes on behavior and decision-making in groups. Here we show that rhesus macaques spontaneously derive vicarious reinforcement from observing rewards given to another monkey, and that this reinforcement can motivate them to subsequently deliver or withhold rewards from the other animal. We exploited Pavlovian and instrumental conditioning to associate rewards to self (M1 and/or rewards to another monkey (M2 with visual cues. M1s made more errors in the instrumental trials when cues predicted reward to M2 compared to when cues predicted reward to M1, but made even more errors when cues predicted reward to no one. In subsequent preference tests between pairs of conditioned cues, M1s preferred cues paired with reward to M2 over cues paired with reward to no one. By contrast, M1s preferred cues paired with reward to self over cues paired with reward to both monkeys simultaneously. Rates of attention to M2 strongly predicted the strength and valence of vicarious reinforcement. These patterns of behavior, which were absent in nonsocial control trials, are consistent with vicarious reinforcement based upon sensitivity to observed, or counterfactual, outcomes with respect to another individual. Vicarious reward may play a critical role in shaping cooperation and competition, as well as motivating observational learning and group coordination in rhesus macaques, much as it does in humans. We propose that vicarious reinforcement signals mediate these behaviors via homologous neural circuits involved in reinforcement learning and decision-making.

  20. Vicarious reinforcement in rhesus macaques (macaca mulatta).

    Science.gov (United States)

    Chang, Steve W C; Winecoff, Amy A; Platt, Michael L

    2011-01-01

    What happens to others profoundly influences our own behavior. Such other-regarding outcomes can drive observational learning, as well as motivate cooperation, charity, empathy, and even spite. Vicarious reinforcement may serve as one of the critical mechanisms mediating the influence of other-regarding outcomes on behavior and decision-making in groups. Here we show that rhesus macaques spontaneously derive vicarious reinforcement from observing rewards given to another monkey, and that this reinforcement can motivate them to subsequently deliver or withhold rewards from the other animal. We exploited Pavlovian and instrumental conditioning to associate rewards to self (M1) and/or rewards to another monkey (M2) with visual cues. M1s made more errors in the instrumental trials when cues predicted reward to M2 compared to when cues predicted reward to M1, but made even more errors when cues predicted reward to no one. In subsequent preference tests between pairs of conditioned cues, M1s preferred cues paired with reward to M2 over cues paired with reward to no one. By contrast, M1s preferred cues paired with reward to self over cues paired with reward to both monkeys simultaneously. Rates of attention to M2 strongly predicted the strength and valence of vicarious reinforcement. These patterns of behavior, which were absent in non-social control trials, are consistent with vicarious reinforcement based upon sensitivity to observed, or counterfactual, outcomes with respect to another individual. Vicarious reward may play a critical role in shaping cooperation and competition, as well as motivating observational learning and group coordination in rhesus macaques, much as it does in humans. We propose that vicarious reinforcement signals mediate these behaviors via homologous neural circuits involved in reinforcement learning and decision-making.

  1. Vicarious learning from human models in monkeys.

    Science.gov (United States)

    Falcone, Rossella; Brunamonti, Emiliano; Genovesio, Aldo

    2012-01-01

    We examined whether monkeys can learn by observing a human model, through vicarious learning. Two monkeys observed a human model demonstrating an object-reward association and consuming food found underneath an object. The monkeys observed human models as they solved more than 30 learning problems. For each problem, the human models made a choice between two objects, one of which concealed a piece of apple. In the test phase afterwards, the monkeys made a choice of their own. Learning was apparent from the first trial of the test phase, confirming the ability of monkeys to learn by vicarious observation of human models.

  2. Vicarious learning from human models in monkeys.

    Directory of Open Access Journals (Sweden)

    Rossella Falcone

    Full Text Available We examined whether monkeys can learn by observing a human model, through vicarious learning. Two monkeys observed a human model demonstrating an object-reward association and consuming food found underneath an object. The monkeys observed human models as they solved more than 30 learning problems. For each problem, the human models made a choice between two objects, one of which concealed a piece of apple. In the test phase afterwards, the monkeys made a choice of their own. Learning was apparent from the first trial of the test phase, confirming the ability of monkeys to learn by vicarious observation of human models.

  3. Vicarious Posttraumatic Growth in Labor and Delivery Nurses.

    Science.gov (United States)

    Beck, Cheryl Tatano; Eaton, Carrie Morgan; Gable, Robert K

    To investigate vicarious posttraumatic growth in labor and delivery nurses who cared for women during traumatic births. A convergent parallel mixed-methods design was used. The sample consisted of 467 labor and delivery nurses who completed the quantitative portion and 295 (63%) who completed the qualitative portion of this mixed-methods study via the Internet. The Association of Women's Health, Obstetric and Neonatal Nurses sent out e-mails to members who were labor and delivery nurses with a link to the electronic survey. Labor and delivery nurses completed the Posttraumatic Growth Inventory and the Core Beliefs Inventory in the quantitative portion. For the qualitative portion, the nurses were asked to describe their experiences of any positive changes in their beliefs or life as a result of their care for women during traumatic births. Labor and delivery nurses who cared for women during traumatic births reported a moderate amount of vicarious posttraumatic growth as indicated by their Posttraumatic Growth Inventory scores. Appreciation of Life was the dimension of the Posttraumatic Growth Inventory that reflected the highest growth, followed by Relating to Others, Personal Strength, Spiritual Change, and New Possibilities. In the qualitative findings, Relating to Others was also the dimension of posttraumatic growth most frequently described. We compared our results with those of previous studies in which researchers assessed vicarious posttraumatic growth in clinicians, and we found that labor and delivery nurses who cared for women during traumatic births experienced growth levels that were scored between the lowest and highest reported levels of therapists and social workers. Nurses need to be aware of the potential to experience this growth despite the significant stress and unpredictability of the labor and delivery environment, which could decrease burnout and improve retention rates. Copyright © 2016 AWHONN, the Association of Women’s Health

  4. Common and distinct neural mechanisms associated with the conscious experience of vicarious pain.

    Science.gov (United States)

    Grice-Jackson, Thomas; Critchley, Hugo D; Banissy, Michael J; Ward, Jamie

    2017-09-01

    Vicarious pain perception has been an influential paradigm for investigating the social neuroscience of empathy. This research has highlighted the importance of both shared representations (i.e., involved in both experiencing first-hand physical pain and observing pain) and mechanisms that discriminate between self and other. The majority of this research has been conducted in healthy younger adults using a group-average approach. There are, however, known inter-individual differences that can contribute to vicarious experience. One factor relates to the degree to which individuals experience reportable pain-like sensations/feelings in response to seeing others in pain. Here we conduct the first systematic investigation of the neural basis of conscious vicarious pain in a large sample of participants. Using cluster analysis, we firstly demonstrate that consciously experiencing the pain of others is surprisingly prevalent and, exists in two forms: one group experiences sensory and localised pain whilst the other group report affective and non-localised experiences. Building on this, we used electroencephalography (EEG) and structural brain imaging to examine the neural correlates of vicarious pain in the three different groups. We find that the dominant electrophysiological marker used to index vicarious pain in previous studies (mu and beta suppression) was only found to be significant in the sensory and localised pain responder group (with a sensitive null result in the 'neurotypical' group). Finally, using voxel-based morphometry (VBM) we identify a common differences in the two pain responder groups relative to typical adults; namely increased grey-matter in insula and somatosensory cortex and reduced grey matter in the right temporo-parietal junction (rTPJ). We suggest that the latter reflects a reduced ability to distinguish bodily self and other, and may be a common factor distinguishing conscious from unconscious vicarious experience. Copyright © 2017

  5. Vicarious Learning from Human Models in Monkeys

    OpenAIRE

    Falcone, Rossella; Brunamonti, Emiliano; Genovesio, Aldo

    2012-01-01

    We examined whether monkeys can learn by observing a human model, through vicarious learning. Two monkeys observed a human model demonstrating an object-reward association and consuming food found underneath an object. The monkeys observed human models as they solved more than 30 learning problems. For each problem, the human models made a choice between two objects, one of which concealed a piece of apple. In the test phase afterwards, the monkeys made a choice of their own. Learning was app...

  6. The relative roles of vicariance versus elevational gradients in the genetic differentiation of the high Andean tree frog, Dendropsophus labialis.

    Science.gov (United States)

    Guarnizo, Carlos E; Amézquita, Adolfo; Bermingham, Eldredge

    2009-01-01

    There are two main competing hypotheses (vicariance and vertical ecotones) that attempt to explain the tremendous diversity of the tropical Andes. We test these hypotheses at the intraspecific level by analyzing mitochondrial and nuclear DNA sequences from 24 populations of the high Andean frog, Dendropsophus labialis (Anura: Hylidae). This species displays geographic variation in a number of phenotypic traits. Most of these traits covary with elevation, while few vary along the horizontal (latitudinal) axis. We found that, both, vicariance and elevation had important effects on the genetic differentiation in this species. We detected two highly divergent clades along the south-north axis using independent information from mitochondrial and nuclear genes, suggesting that this differentiation was the result of long-term barriers to gene flow rather than stochastic processes. We hypothesize mechanisms for D. labialis strong differentiation in light of geological and paleoenvironmental models of evolution in the northern Andean highlands.

  7. Vicarious audiovisual learning in perfusion education.

    Science.gov (United States)

    Rath, Thomas E; Holt, David W

    2010-12-01

    Perfusion technology is a mechanical and visual science traditionally taught with didactic instruction combined with clinical experience. It is difficult to provide perfusion students the opportunity to experience difficult clinical situations, set up complex perfusion equipment, or observe corrective measures taken during catastrophic events because of patient safety concerns. Although high fidelity simulators offer exciting opportunities for future perfusion training, we explore the use of a less costly low fidelity form of simulation instruction, vicarious audiovisual learning. Two low fidelity modes of instruction; description with text and a vicarious, first person audiovisual production depicting the same content were compared. Students (n = 37) sampled from five North American perfusion schools were prospectively randomized to one of two online learning modules, text or video.These modules described the setup and operation of the MAQUET ROTAFLOW stand-alone centrifugal console and pump. Using a 10 question multiple-choice test, students were assessed immediately after viewing the module (test #1) and then again 2 weeks later (test #2) to determine cognition and recall of the module content. In addition, students completed a questionnaire assessing the learning preferences of today's perfusion student. Mean test scores from test #1 for video learners (n = 18) were significantly higher (88.89%) than for text learners (n = 19) (74.74%), (p learning module than text learners. Vicarious audiovisual learning modules may be an efficacious, low cost means of delivering perfusion training on subjects such as equipment setup and operation. Video learning appears to improve cognition and retention of learned content and may play an important role in how we teach perfusion in the future, as simulation technology becomes more prevalent.

  8. Vicarious learning through capturing taskdirected discussions

    Directory of Open Access Journals (Sweden)

    F. Dineen

    1999-12-01

    Full Text Available The research programme on vicarious learning, part of which we report in this paper, has been aimed at exploring the idea that learning can be facilitated by providing learners with access to the experiences of other learners. We use Bandura's term vicarious learning to describe this (Bandura, 1986, and we believe it to be a paradigm that offers particular promise when seen as an innovative way of exploiting recent technical advances in multimedia and distance learning technologies. It offers the prospect of a real alternative to the building of intelligent tutors (which directly address the problem of allowing learners access to dialogue, but which have proved largely intractable in practice or to the direct support of live dialogues (which do not offer a solution to the problem of providing 'live' tutors - unless they are between peer learners. In the research reported here our main objectives were to develop techniques to facilitate learners' access to, especially, dialogues and discussions which have arisen when other learners were faced with similar issues or problems in understanding the material. This required us to investigate means of indexing and retrieving appropriate dialogues and build on these to create an advanced prototype system for use in educational settings.

  9. A comparison of positive vicarious learning and verbal information for reducing vicariously learned fear

    OpenAIRE

    Reynolds, Gemma; Wasely, David; Dunne, Guler; Askew, Chris

    2017-01-01

    Research with children has demonstrated that both positive vicarious learning (modelling) and positive verbal information can reduce children’s acquired fear responses for a particular stimulus. However, this fear reduction appears to be more effective when the intervention pathway matches the initial fear learning pathway. That is, positive verbal information is a more effective intervention than positive modelling when fear is originally acquired via negative verbal information. Research ha...

  10. The vicarious learning pathway to fear 40 years on.

    Science.gov (United States)

    Askew, Chris; Field, Andy P

    2008-10-01

    Forty years on from the initial idea that fears could be learnt vicariously through observing other people's responses to a situation or stimulus, this review looks at the evidence for this theory as an explanatory model of clinical fear. First, we review early experimental evidence that fears can be learnt vicariously before turning to the evidence from both primate and human research that clinical fears can be acquired in this way. Finally, we review recent evidence from research on non-anxious children. Throughout the review we highlight problems and areas for future research. We conclude by exploring the likely underlying mechanisms in the vicarious learning of fear and the resulting clinical implications.

  11. Historical vicariance and postglacial colonization effects on the evolution of genetic structure in Lophocereus, a Sonoran Desert columnar cactus.

    Science.gov (United States)

    Nason, John D; Hamrick, J L; Fleming, Theodore H

    2002-11-01

    Distinguishing the historical effects of gene migration and vicariance on contemporary genetic structure is problematic without testable biogeographic hypotheses based on preexisting geological and environmental evidence. The availability of such hypotheses for North America's Sonoran Desert has contributed to our understanding of the effect of historical vicariance and dispersal events on the diversification of this region's vertebrate biota but have not yet been applied to its flora. In this paper we describe a detailed allozyme analysis of the population genetic structure and phylogeography of the Sonoran Desert columnar cactus, Lophocereus schottii (senita). Inferred phylogroup distributions reflect two historical vicariance events: (1) a middle Pliocene northward transgression of the Sea of Cortéz that is reflected in well-supported Baja California peninsular and continental phylogroups but not in current taxonomic treatments of the species; and (2) a late Pliocene transpeninsular seaway across southern Baja that is reflected in tentative support for peninsular and southern Cape Region phylogroups corresponding to taxonomic varieties L. schottii var. schottii and L. schottii var. australis, respectively. A middle Pleistocene midpeninsular seaway hypothesized to explain congruent phylogroup distributions in several vertebrate taxa is not reflected in L. s. var. schottii, nor is the distinction of a third variety, L. s. var. tenuis, from continental populations of L. s. var. schottii. Linear regression of pairwise estimates of interpopulation differentiation (M and F(ST)/[1 - F(ST)]) on interpopulation geographic distance revealed significant evidence of isolation by distance within peninsular and continental phylogroups but not between them, consistent with historical vicariance between but not within these regions. We also found significant evidence of isolation by distance between putative L. s. var. schottii and L. s. var. australis phylogroups, suggesting

  12. Vicarious reinforcement learning signals when instructing others.

    Science.gov (United States)

    Apps, Matthew A J; Lesage, Elise; Ramnani, Narender

    2015-02-18

    Reinforcement learning (RL) theory posits that learning is driven by discrepancies between the predicted and actual outcomes of actions (prediction errors [PEs]). In social environments, learning is often guided by similar RL mechanisms. For example, teachers monitor the actions of students and provide feedback to them. This feedback evokes PEs in students that guide their learning. We report the first study that investigates the neural mechanisms that underpin RL signals in the brain of a teacher. Neurons in the anterior cingulate cortex (ACC) signal PEs when learning from the outcomes of one's own actions but also signal information when outcomes are received by others. Does a teacher's ACC signal PEs when monitoring a student's learning? Using fMRI, we studied brain activity in human subjects (teachers) as they taught a confederate (student) action-outcome associations by providing positive or negative feedback. We examined activity time-locked to the students' responses, when teachers infer student predictions and know actual outcomes. We fitted a RL-based computational model to the behavior of the student to characterize their learning, and examined whether a teacher's ACC signals when a student's predictions are wrong. In line with our hypothesis, activity in the teacher's ACC covaried with the PE values in the model. Additionally, activity in the teacher's insula and ventromedial prefrontal cortex covaried with the predicted value according to the student. Our findings highlight that the ACC signals PEs vicariously for others' erroneous predictions, when monitoring and instructing their learning. These results suggest that RL mechanisms, processed vicariously, may underpin and facilitate teaching behaviors. Copyright © 2015 Apps et al.

  13. Testing statistical hypotheses

    CERN Document Server

    Lehmann, E L

    2005-01-01

    The third edition of Testing Statistical Hypotheses updates and expands upon the classic graduate text, emphasizing optimality theory for hypothesis testing and confidence sets. The principal additions include a rigorous treatment of large sample optimality, together with the requisite tools. In addition, an introduction to the theory of resampling methods such as the bootstrap is developed. The sections on multiple testing and goodness of fit testing are expanded. The text is suitable for Ph.D. students in statistics and includes over 300 new problems out of a total of more than 760. E.L. Lehmann is Professor of Statistics Emeritus at the University of California, Berkeley. He is a member of the National Academy of Sciences and the American Academy of Arts and Sciences, and the recipient of honorary degrees from the University of Leiden, The Netherlands and the University of Chicago. He is the author of Elements of Large-Sample Theory and (with George Casella) he is also the author of Theory of Point Estimat...

  14. On the distinction of empathic and vicarious emotions

    Science.gov (United States)

    Paulus, Frieder M.; Müller-Pinzler, Laura; Westermann, Stefan; Krach, Sören

    2013-01-01

    In the introduction to the special issue “The Neural Underpinnings of Vicarious Experience” the editors state that one “may feel embarrassed when witnessing another making a social faux pas”. In our commentary we address this statement and ask whether this example introduces a vicarious or an empathic form of embarrassment. We elaborate commonalities and differences between these two forms of emotional experiences and discuss their underlying mechanisms. We suggest that both, vicarious and empathic emotions, originate from the simulation processes mirroring and mentalizing that depend on anchoring and adjustment. We claim the term “empathic emotion” to be reserved exclusively for incidents where perceivers and social targets have shared affective experience, whereas “vicarious emotion” offers a wider scope and also includes non-shared affective experiences. Both are supposed to be highly functional in social interactions. PMID:23720621

  15. Vicarious Calibration of Beijing-1 Multispectral Imagers

    Directory of Open Access Journals (Sweden)

    Zhengchao Chen

    2014-02-01

    Full Text Available For on-orbit calibration of the Beijing-1 multispectral imagers (Beijing-1/MS, a field calibration campaign was performed at the Dunhuang calibration site during September and October of 2008. Based on the in situ data and images from Beijing-1 and Terra/Moderate Resolution Imaging Spectroradiometer (MODIS, three vicarious calibration methods (i.e., reflectance-based, irradiance-based, and cross-calibration were used to calculate the top-of-atmosphere (TOA radiance of Beijing-1. An analysis was then performed to determine or identify systematic and accidental errors, and the overall uncertainty was assessed for each individual method. The findings show that the reflectance-based method has an uncertainty of more than 10% if the aerosol optical depth (AOD exceeds 0.2. The cross-calibration method is able to reach an error level within 7% if the images are selected carefully. The final calibration coefficients were derived from the irradiance-based data for 6 September 2008, with an uncertainty estimated to be less than 5%.

  16. Vicarious resilience and vicarious traumatisation: Experiences of working with refugees and asylum seekers in South Australia.

    Science.gov (United States)

    Puvimanasinghe, Teresa; Denson, Linley A; Augoustinos, Martha; Somasundaram, Daya

    2015-12-01

    The negative psychological impacts of working with traumatised people are well documented and include vicarious traumatisation (VT): the cumulative effect of identifying with clients' trauma stories that negatively impacts on service providers' memory, emotions, thoughts, and worldviews. More recently, the concept of vicarious resilience (VR) has been also identified: the strength, growth, and empowerment experienced by trauma workers as a consequence of their work. VR includes service providers' awareness and appreciation of their clients' capacity to grow, maintaining hope for change, as well as learning from and reassessing personal problems in the light of clients' stories of perseverance, strength, and growth. This study aimed at exploring the experiences of mental health, physical healthcare, and settlement workers caring for refugees and asylum seekers in South Australia. Using a qualitative method (data-based thematic analysis) to collect and analyse 26 semi-structured face-to-face interviews, we identified four prominent and recurring themes emanating from the data: VT, VR, work satisfaction, and cultural flexibility. These findings-among the first to describe both VT and VR in Australians working with refugee people-have important implications for policy, service quality, service providers' wellbeing, and refugee clients' lives. © The Author(s) 2015.

  17. Functions of personal and vicarious life stories: Identity and empathy

    DEFF Research Database (Denmark)

    Lind, Majse; Thomsen, Dorthe Kirkegaard

    2018-01-01

    The present study investigates functions of personal and vicarious life stories focusing on identity and empathy. Two-hundred-and-forty Danish high school students completed two life story questionnaires: One for their personal life story and one for a close other’s life story. In both...... questionnaires, they identified up to 10 chapters and self-rated the chapters on valence and valence of causal connections. In addition, they completed measures of identity disturbance and empathy. More positive personal life stories were related to lower identity disturbance and higher empathy. Vicarious life...... stories showed a similar pattern with respect to identity but surprisingly were unrelated to empathy. In addition, we found positive correlations between personal and vicarious life stories for number of chapters, chapter valence, and valence of causal connections. The study indicates that both personal...

  18. When Caring for Perpetrators Becomes a Sentence: Recognizing Vicarious Trauma.

    Science.gov (United States)

    Munger, Tanya; Savage, Teresa; Panosky, Denise M

    2015-10-01

    Correctional health nurses are not exempt from vicarious traumatization, but this concept has yet to be explored. Correctional health nurses practice in environments that come with significant risk for traumatic exposure from inmates and coworkers. The Professional Quality of Life Scale was used as a proxy to measure vicarious trauma. Surveys were mailed to 2,000 correctional health nurses that were on the mailing list of the National Commission on Correctional Health Care, with a total response rate of 10.1%. Respondents were asked to complete the Professional Quality of Life Scale and a short demographic survey. Findings reveal that vicarious traumatization does exist among correctional health nurses. © The Author(s) 2015.

  19. Types of vicarious learning experienced by pre-dialysis patients.

    Science.gov (United States)

    McCarthy, Kate; Sturt, Jackie; Adams, Ann

    2015-01-01

    Haemodialysis and peritoneal dialysis renal replacement treatment options are in clinical equipoise, although the cost of haemodialysis to the National Health Service is £16,411/patient/year greater than peritoneal dialysis. Treatment decision-making takes place during the pre-dialysis year when estimated glomerular filtration rate drops to between 15 and 30 mL/min/1.73 m(2). Renal disease can be familial, and the majority of patients have considerable health service experience when they approach these treatment decisions. Factors affecting patient treatment decisions are currently unknown. The objective of this article is to explore data from a wider study in specific relation to the types of vicarious learning experiences reported by pre-dialysis patients. A qualitative study utilised unstructured interviews and grounded theory analysis during the participant's pre-dialysis year. The interview cohort comprised 20 pre-dialysis participants between 24 and 80 years of age. Grounded theory design entailed thematic sampling and analysis, scrutinised by secondary coding and checked with participants. Participants were recruited from routine renal clinics at two local hospitals when their estimated glomerular filtration rate was between 15 and 30 mL/min/1.73 m(2). Vicarious learning that contributed to treatment decision-making fell into three main categories: planned vicarious leaning, unplanned vicarious learning and historical vicarious experiences. Exploration and acknowledgement of service users' prior vicarious learning, by healthcare professionals, is important in understanding its potential influences on individuals' treatment decision-making. This will enable healthcare professionals to challenge heuristic decisions based on limited information and to encourage analytic thought processes.

  20. Types of vicarious learning experienced by pre-dialysis patients

    Directory of Open Access Journals (Sweden)

    Kate McCarthy

    2015-04-01

    Full Text Available Objective: Haemodialysis and peritoneal dialysis renal replacement treatment options are in clinical equipoise, although the cost of haemodialysis to the National Health Service is £16,411/patient/year greater than peritoneal dialysis. Treatment decision-making takes place during the pre-dialysis year when estimated glomerular filtration rate drops to between 15 and 30 mL/min/1.73 m2. Renal disease can be familial, and the majority of patients have considerable health service experience when they approach these treatment decisions. Factors affecting patient treatment decisions are currently unknown. The objective of this article is to explore data from a wider study in specific relation to the types of vicarious learning experiences reported by pre-dialysis patients. Methods: A qualitative study utilised unstructured interviews and grounded theory analysis during the participant’s pre-dialysis year. The interview cohort comprised 20 pre-dialysis participants between 24 and 80 years of age. Grounded theory design entailed thematic sampling and analysis, scrutinised by secondary coding and checked with participants. Participants were recruited from routine renal clinics at two local hospitals when their estimated glomerular filtration rate was between 15 and 30 mL/min/1.73 m2. Results: Vicarious learning that contributed to treatment decision-making fell into three main categories: planned vicarious leaning, unplanned vicarious learning and historical vicarious experiences. Conclusion: Exploration and acknowledgement of service users’ prior vicarious learning, by healthcare professionals, is important in understanding its potential influences on individuals’ treatment decision-making. This will enable healthcare professionals to challenge heuristic decisions based on limited information and to encourage analytic thought processes.

  1. Reality TV and vicarious embarrassment: an fMRI study.

    Science.gov (United States)

    Melchers, Martin; Markett, Sebastian; Montag, Christian; Trautner, Peter; Weber, Bernd; Lachmann, Bernd; Buss, Pauline; Heinen, Rebekka; Reuter, Martin

    2015-04-01

    Vicarious embarrassment (VE) is an emotion triggered by the observation of others' pratfalls or social norm violations. Several explanatory approaches have been suggested to explain the source of this phenomenon, including perspective taking abilities or ingroup identification. Knowledge about its biological bases, however, is scarce. To gain a better understanding, the present study investigated neural activation patterns in response to video clips from reality TV shows. Reality TV is well known for presenting social norm violations, flaws and pratfalls of its protagonists in real life situations thereby qualifying as an ecological valid trigger for VE. N = 60 healthy participants viewed stand stills from previously watched video clips taken from German reality TV-shows while undergoing functional magnetic resonance imaging. The clips were preselected for high versus low VE content in a pilot study. Besides the investigation of differences in brain activation elicited by VE versus control stand stills (blocked design contrast), we performed additional exploratory functional connectivity analyses (psychophysiological interaction; PPI) to detect VE related brain networks. Compared to the low VE condition, participants in the high VE condition showed a higher activation in the middle temporal gyrus, the supramarginal gyrus, the right inferior frontal gyrus and the gyrus rectus. Functional connectivity analyses confirmed increased connectivity of these regions with the anterior cingulate in the VE condition. Moreover, self-ratings of VE and brain activity were correlated positively. Reality TV formats with high VE content activate brain regions associated with Theory of Mind, but also with empathic concern and social identity. Therefore, our results support the idea that the ability to put oneself in other person's shoes is a major prerequisite for VE. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Scientific 'Laws', 'Hypotheses' and 'Theories'

    Indian Academy of Sciences (India)

    No.10,1998. J R Lakshmana Rao. Some commonly held erroneous notions about the terms laws, hypotheses and theories are pointed out with specific examples from different branches of science. Hypotheses ... John Stuart Mill, who is spoken of as the father of induction and who, in the ..... True Science is a wild adventure.

  3. Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal.

    Science.gov (United States)

    Korall, Petra; Pryer, Kathleen M

    2014-02-01

    Scaly tree ferns, Cyatheaceae, are a well-supported group of mostly tree-forming ferns found throughout the tropics, the subtropics and the south-temperate zone. Fossil evidence shows that the lineage originated in the Late Jurassic period. We reconstructed large-scale historical biogeographical patterns of Cyatheaceae and tested the hypothesis that some of the observed distribution patterns are in fact compatible, in time and space, with a vicariance scenario related to the break-up of Gondwana. Tropics, subtropics and south-temperate areas of the world. The historical biogeography of Cyatheaceae was analysed in a maximum likelihood framework using Lagrange. The 78 ingroup taxa are representative of the geographical distribution of the entire family. The phylogenies that served as a basis for the analyses were obtained by Bayesian inference analyses of mainly previously published DNA sequence data using MrBayes. Lineage divergence dates were estimated in a Bayesian Markov chain Monte Carlo framework using beast. Cyatheaceae originated in the Late Jurassic in either South America or Australasia. Following a range expansion, the ancestral distribution of the marginate-scaled clade included both these areas, whereas Sphaeropteris is reconstructed as having its origin only in Australasia. Within the marginate-scaled clade, reconstructions of early divergences are hampered by the unresolved relationships among the Alsophila , Cyathea and Gymnosphaera lineages. Nevertheless, it is clear that the occurrence of the Cyathea and Sphaeropteris lineages in South America may be related to vicariance, whereas transoceanic dispersal needs to be inferred for the range shifts seen in Alsophila and Gymnosphaera . The evolutionary history of Cyatheaceae involves both Gondwanan vicariance scenarios as well as long-distance dispersal events. The number of transoceanic dispersals reconstructed for the family is rather few when compared with other fern lineages. We suggest that a causal

  4. Vicarious motor activation during action perception: beyond correlational evidence

    Directory of Open Access Journals (Sweden)

    Alessio eAvenanti

    2013-05-01

    Full Text Available Neurophysiological and imaging studies have shown that seeing the actions of other individuals brings about the vicarious activation of motor regions involved in performing the same actions. While this suggests a simulative mechanism mediating the perception of others’ actions, one cannot use such evidence to make inferences about the functional significance of vicarious activations. Indeed, a central aim in social neuroscience is to comprehend how vicarious activations allow the understanding of other people’s behavior, and this requires to use stimulation or lesion methods to establish causal links from brain activity to cognitive functions. In the present work we review studies investigating the effects of transient manipulations of brain activity or stable lesions in the motor system on individuals’ ability to perceive and understand the actions of others. We conclude there is now compelling evidence that neural activity in the motor system is critical for such cognitive ability. More research using causal methods, however, is needed in order to disclose the limits and the conditions under which vicarious activations are required to perceive and understand actions of others as well as their emotions and somatic feelings.

  5. Sexual Violence and Vicarious Trauma: A Case Study | Ilesanmi ...

    African Journals Online (AJOL)

    Using a case study approach, this quantitative and descriptive analysis explored the incidence and consequences of sexual violence, particularly rape, occurring among Nigerian university students' acquaintance. It discusses the concept of vicarious trauma as a form of post-traumatic stress response sometimes ...

  6. An Examination of Vicarious Reinforcement Processes in Children.

    Science.gov (United States)

    Ollendick, Thomas H.; Shapiro, Edward S.

    1984-01-01

    Explores effects on one child of observing another same-sex child receive direct reinforcement. Subjects were 216 children from different age levels (6.11, 9.1, and 11.2 years). Results were considered in terms of vicarious reinforcement and the "implicit punishment" hypothesis. (Author/CI)

  7. Promoting Vicarious Learning of Physics Using Deep Questions with Explanations

    Science.gov (United States)

    Craig, Scotty D.; Gholson, Barry; Brittingham, Joshua K.; Williams, Joah L.; Shubeck, Keith T.

    2012-01-01

    Two experiments explored the role of vicarious "self" explanations in facilitating student learning gains during computer-presented instruction. In Exp. 1, college students with low or high knowledge on Newton's laws were tested in four conditions: (a) monologue (M), (b) questions (Q), (c) explanation (E), and (d) question + explanation (Q + E).…

  8. Comparing Learning from Productive Failure and Vicarious Failure

    Science.gov (United States)

    Kapur, Manu

    2014-01-01

    A total of 136 eighth-grade math students from 2 Singapore schools learned from either productive failure (PF) or vicarious failure (VF). PF students "generated" solutions to a complex problem targeting the concept of variance that they had not learned yet before receiving instruction on the targeted concept. VF students…

  9. Expanding the mirror : vicarious activity for actions, emotions, and sensations

    NARCIS (Netherlands)

    Keysers, Christian; Gazzola, Valeria

    2009-01-01

    We often empathically share the states of others. The discovery of 'mirror neurons' suggested a neural mechanism for monkeys to share the actions of others. Here we expand this view by showing that mirror neurons for actions not only exist in the premotor cortex or in monkeys and that vicarious

  10. Campaign for vicarious calibration of SumbandilaSat in Argentina

    CSIR Research Space (South Africa)

    Vhengani, LM

    2011-07-01

    Full Text Available to estimate Top-Of-Atmosphere (TOA) spectral radiance. A vicarious calibration field campaign was executed in Argentina to support monitoring of the radiometric response of the multispectral imager aboard SumbandilaSat. Results obtained using two Radiative...

  11. The role of empathy in experiencing vicarious anxiety.

    Science.gov (United States)

    Shu, Jocelyn; Hassell, Samuel; Weber, Jochen; Ochsner, Kevin N; Mobbs, Dean

    2017-08-01

    With depictions of others facing threats common in the media, the experience of vicarious anxiety may be prevalent in the general population. However, the phenomenon of vicarious anxiety-the experience of anxiety in response to observing others expressing anxiety-and the interpersonal mechanisms underlying it have not been fully investigated in prior research. In 4 studies, we investigate the role of empathy in experiencing vicarious anxiety, using film clips depicting target victims facing threats. In Studies 1 and 2, trait emotional empathy was associated with greater self-reported anxiety when observing target victims, and with perceiving greater anxiety to be experienced by the targets. Study 3 extended these findings by demonstrating that trait empathic concern-the tendency to feel concern and compassion for others-was associated with experiencing vicarious anxiety, whereas trait personal distress-the tendency to experience distress in stressful situations-was not. Study 4 manipulated state empathy to establish a causal relationship between empathy and experience of vicarious anxiety. Participants who took an empathic perspective when observing target victims, as compared to those who took an objective perspective using reappraisal-based strategies, reported experiencing greater anxiety, risk-aversion, and sleep disruption the following night. These results highlight the impact of one's social environment on experiencing anxiety, particularly for those who are highly empathic. In addition, these findings have implications for extending basic models of anxiety to incorporate interpersonal processes, understanding the role of empathy in social learning, and potential applications for therapeutic contexts. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  12. Hypotheses to explain the origin of species in Amazonia

    Directory of Open Access Journals (Sweden)

    J. Haffer

    Full Text Available The main hypotheses proposed to explain barrier formation separating populations and causing the differentiation of species in Amazonia during the course of geological history are based on different factors, as follow: (1 Changes in the distribution of land and sea or in the landscape due to tectonic movements or sea level fluctuations (Paleogeography hypothesis, (2 the barrier effect of Amazonian rivers (River hypothesis, (3 a combination of the barrier effect of broad rivers and vegetational changes in northern and southern Amazonia (River-refuge hypothesis, (4 the isolation of humid rainforest blocks near areas of surface relief in the periphery of Amazonia separated by dry forests, savannas and other intermediate vegetation types during dry climatic periods of the Tertiary and Quaternary (Refuge hypothesis, (5 changes in canopy-density due to climatic reversals (Canopy-density hypothesis (6 the isolation and speciation of animal populations in small montane habitat pockets around Amazonia due to climatic fluctuations without major vegetational changes (Museum hypothesis, (7 competitive species interactions and local species isolations in peripheral regions of Amazonia due to invasion and counterinvasion during cold/warm periods of the Pleistocene (Disturbance-vicariance hypothesis and (8 parapatric speciation across steep environmental gradients without separation of the respective populations (Gradient hypothesis. Several of these hypotheses probably are relevant to a different degree for the speciation processes in different faunal groups or during different geological periods. The basic paleogeography model refers mainly to faunal differentiation during the Tertiary and in combination with the Refuge hypothesis. Milankovitch‡ cycles leading to global main hypotheses proposed to explain barrier formation separating populations and causing the differentiation of species in Amazonia during the course of geological history are based on

  13. Hypotheses to explain the origin of species in Amazonia.

    Science.gov (United States)

    Haffer, J

    2008-11-01

    The main hypotheses proposed to explain barrier formation separating populations and causing the differentiation of species in Amazonia during the course of geological history are based on different factors, as follow: (1) Changes in the distribution of land and sea or in the landscape due to tectonic movements or sea level fluctuations (Paleogeography hypothesis), (2) the barrier effect of Amazonian rivers (River hypothesis), (3) a combination of the barrier effect of broad rivers and vegetational changes in northern and southern Amazonia (River-refuge hypothesis), (4) the isolation of humid rainforest blocks near areas of surface relief in the periphery of Amazonia separated by dry forests, savannas and other intermediate vegetation types during dry climatic periods of the Tertiary and Quaternary (Refuge hypothesis), (5) changes in canopy-density due to climatic reversals (Canopy-density hypothesis) (6) the isolation and speciation of animal populations in small montane habitat pockets around Amazonia due to climatic fluctuations without major vegetational changes (Museum hypothesis), (7) competitive species interactions and local species isolations in peripheral regions of Amazonia due to invasion and counterinvasion during cold/warm periods of the Pleistocene (Disturbance-vicariance hypothesis) and (8) parapatric speciation across steep environmental gradients without separation of the respective populations (Gradient hypothesis). Several of these hypotheses probably are relevant to a different degree for the speciation processes in different faunal groups or during different geological periods. The basic paleogeography model refers mainly to faunal differentiation during the Tertiary and in combination with the Refuge hypothesis. Milankovitch cycles leading to global main hypotheses proposed to explain barrier formation separating populations and causing the differentiation of species in Amazonia during the course of geological history are based on different

  14. [Puzzles and hypotheses of acupuncture].

    Science.gov (United States)

    Li, Yong-ming

    2013-11-01

    Some results of clinical trials from the West on traditional acupuncture with modern research design have puzzled the acupuncture community. These include (1) what is the implication of acupuncture, (2) whether acupuncture point has its specificity, and 3) why practical experience in the East is quite different from research observations in the West. Three hypotheses, namely, Acupuncture Healing Effect, Pan-acupoint Phenomenon, and Hard Acupuncture and Soft Acupuncture, are proposed here to explain these sensitive issues. Further investigation with scientific approach may prove or reject these hypotheses. The resolving of these issues will shed light on the re-evaluation of traditional acupuncture and promote the maturation of modern acupuncture theory.

  15. Game of Objects: vicarious causation and multi-modal media

    Directory of Open Access Journals (Sweden)

    Aaron Pedinotti

    2013-09-01

    Full Text Available This paper applies philosopher Graham Harman's object-oriented theory of "vicarious causation" to an analysis of the multi-modal media phenomenon known as "Game of Thrones." Examining the manner in which George R.R. Martin's best-selling series of fantasy novels has been adapted into a board game, a video game, and a hit HBO television series, it uses the changes entailed by these processes to trace the contours of vicariously generative relations. In the course of the resulting analysis, it provides new suggestions concerning the eidetic dimensions of Harman's causal model, particularly with regard to causation in linear networks and in differing types of game systems.

  16. Scanning and vicarious learning from adverse events in health care

    Directory of Open Access Journals (Sweden)

    2001-01-01

    Full Text Available Studies have shown that serious adverse clinical events occur in approximately 3%-10% of acute care hospital admissions, and one third of these adverse events result in permanent disability or death. These findings have led to calls for national medical error reporting systems and for greater organizational learning by hospitals. But do hospitals and hospital personnel pay enough attention to such risk information that they might learn from each other's failures or adverse events? This paper gives an overview of the importance of scanning and vicarious learning from adverse events. In it I propose that health care organizations' attention and information focus, organizational affinity, and absorptive capacity may each influence scanning and vicarious learning outcomes. Implications for future research are discussed.

  17. Scientific 'Laws', 'Hypotheses' and 'Theories'

    Indian Academy of Sciences (India)

    Science endeavours to give a meaningful description of the world of phenomena using what are known as laws, hypotheses and theories. Logicians and students of scientific method analyse the structure of scientific knowledge and try to determine the precise significance of these terms. But it is surprising to note.

  18. Amerind taxonomy and testable hypotheses.

    Science.gov (United States)

    Pichardo, M

    1998-06-01

    The acceptance of a 30,000 yr B.P. age for Valsequillo sets new parameters for hypotheses of Paleoindian entry into America. A review of Amerind taxonomy defines the early groups as Otamid-Sundadonts. Isolation in America led to an adaptive radiation that has implications for the origin and dispersal of Pithecanthropus.

  19. Vicarious Fear Learning Depends on Empathic Appraisals and Trait Empathy.

    Science.gov (United States)

    Olsson, Andreas; McMahon, Kibby; Papenberg, Goran; Zaki, Jamil; Bolger, Niall; Ochsner, Kevin N

    2016-01-01

    Empathy and vicarious learning of fear are increasingly understood as separate phenomena, but the interaction between the two remains poorly understood. We investigated how social (vicarious) fear learning is affected by empathic appraisals by asking participants to either enhance or decrease their empathic responses to another individual (the demonstrator), who received electric shocks paired with a predictive conditioned stimulus. A third group of participants received no appraisal instructions and responded naturally to the demonstrator. During a later test, participants who had enhanced their empathy evinced the strongest vicarious fear learning as measured by skin conductance responses to the conditioned stimulus in the absence of the demonstrator. Moreover, this effect was augmented in observers high in trait empathy. Our results suggest that a demonstrator's expression can serve as a "social" unconditioned stimulus (US), similar to a personally experienced US in Pavlovian fear conditioning, and that learning from a social US depends on both empathic appraisals and the observers' stable traits. © The Author(s) 2015.

  20. Vicarious learning revisited: a contemporary behavior analytic interpretation.

    Science.gov (United States)

    Masia, C L; Chase, P N

    1997-03-01

    Beginning in the 1960s, social learning theorists argued that behavioral learning principles could not account for behavior acquired through observation. Such a viewpoint is still widely held today. This rejection of behavioral principles in explaining vicarious learning was based on three phenomena: (1) imitation that occurred without direct reinforcement of the observer's behavior; (2) imitation that occurred after a long delay following modeling; and (3) a greater probability of imitation of the model's reinforced behavior than of the model's nonreinforced or punished behavior. These observations convinced social learning theorists that cognitive variables were required to explain behavior. Such a viewpoint has progressed aggressively, as evidenced by the change in name from social learning theory to social cognitive theory, and has been accompanied by the inclusion of information-processing theory. Many criticisms of operant theory, however, have ignored the full range of behavioral concepts and principles that have been derived to account for complex behavior. This paper will discuss some problems with the social learning theory explanation of vicarious learning and provide an interpretation of vicarious learning from a contemporary behavior analytic viewpoint.

  1. Learning to fear a second-order stimulus following vicarious learning

    OpenAIRE

    Reynolds, G; Field, AP; Askew, C

    2015-01-01

    Vicarious fear learning refers to the acquisition of fear via observation of the fearful responses of others. The present study aims to extend current knowledge by exploring whether second-order vicarious fear learning can be demonstrated in children. That is, whether vicariously learnt fear responses for one stimulus can be elicited in a second stimulus associated with that initial stimulus. Results demonstrated that children’s (5–11 years) fear responses for marsupials and caterpillars incr...

  2. Effect of vicarious fear learning on children's heart rate responses and attentional bias for novel animals

    OpenAIRE

    Reynolds, G; Field, AP; Askew, C

    2014-01-01

    Research with children has shown that vicarious learning can result in changes to 2 of Lang's (1968) 3 anxiety response systems: subjective report and behavioral avoidance. The current study extended this research by exploring the effect of vicarious learning on physiological responses (Lang's final response system) and attentional bias. The study used Askew and Field's (2007) vicarious learning procedure and demonstrated fear-related increases in children's cognitive, behavioral, and physiol...

  3. Stimulus fear-relevance and the vicarious learning pathway to childhood fears.

    Science.gov (United States)

    Askew, Chris; Dunne, Güler; Özdil, Zehra; Reynolds, Gemma; Field, Andy P

    2013-10-01

    Enhanced fear learning for fear-relevant stimuli has been demonstrated in procedures with adults in the laboratory. Three experiments investigated the effect of stimulus fear-relevance on vicarious fear learning in children (aged 6-11 years). Pictures of stimuli with different levels of fear-relevance (flowers, caterpillars, snakes, worms, and Australian marsupials) were presented alone or together with scared faces. In line with previous studies, children's fear beliefs and avoidance preferences increased for stimuli they had seen with scared faces. However, in contrast to evidence with adults, learning was mostly similar for all stimulus types irrespective of fear-relevance. The results support a proposal that stimulus preparedness is bypassed when children observationally learn threat-related information from adults.

  4. Testing statistical hypotheses of equivalence

    CERN Document Server

    Wellek, Stefan

    2010-01-01

    Equivalence testing has grown significantly in importance over the last two decades, especially as its relevance to a variety of applications has become understood. Yet published work on the general methodology remains scattered in specialists' journals, and for the most part, it focuses on the relatively narrow topic of bioequivalence assessment.With a far broader perspective, Testing Statistical Hypotheses of Equivalence provides the first comprehensive treatment of statistical equivalence testing. The author addresses a spectrum of specific, two-sided equivalence testing problems, from the

  5. Beyond Vicary's fantasies: The impact of subliminal priming and brand choice

    NARCIS (Netherlands)

    Karremans, J.C.T.M.; Stroebe, W.; Claus, J.

    2006-01-01

    With his claim to have increased sales of Coca Cola and popcorn in a movie theatre through subliminal messages flashed on the screen, James Vicary raised the possibility of subliminal advertising. Nobody has ever replicated Vicary's findings and his study was a hoax. This article reports two

  6. Teaching Parents about Responsive Feeding through a Vicarious Learning Video: A Pilot Randomized Controlled Trial

    Science.gov (United States)

    Ledoux, Tracey; Robinson, Jessica; Baranowski, Tom; O'Connor, Daniel P.

    2018-01-01

    The American Academy of Pediatrics and World Health Organization recommend responsive feeding (RF) to promote healthy eating behaviors in early childhood. This project developed and tested a vicarious learning video to teach parents RF practices. A RF vicarious learning video was developed using community-based participatory research methods.…

  7. Promoting Constructive Activities that Support Vicarious Learning during Computer-Based Instruction

    Science.gov (United States)

    Gholson, Barry; Craig, Scotty D.

    2006-01-01

    This article explores several ways computer-based instruction can be designed to support constructive activities and promote deep-level comprehension during vicarious learning. Vicarious learning, discussed in the first section, refers to knowledge acquisition under conditions in which the learner is not the addressee and does not physically…

  8. Enabling the Development of Student Teacher Professional Identity through Vicarious Learning during an Educational Excursion

    Science.gov (United States)

    Steenekamp, Karen; van der Merwe, Martyn; Mehmedova, Aygul Salieva

    2018-01-01

    This paper explores the views of student teachers who were provided vicarious learning opportunities during an educational excursion, and how the learning enabled them to develop their teacher professional identity. This qualitative research study, using a social-constructivist lens highlights how vicarious learning influenced student teachers'…

  9. Examining the Effect of Small Group Discussions and Question Prompts on Vicarious Learning Outcomes

    Science.gov (United States)

    Lee, Yekyung; Ertmer, Peggy A.

    2006-01-01

    This study investigated the effect of group discussions and question prompts on students' vicarious learning experiences. Vicarious experiences were delivered to 65 preservice teachers via VisionQuest, a Web site that provided examples of successful technology integration. A 2x2 factorial research design employed group discussions and question…

  10. Effects of Competition on Students' Self-Efficacy in Vicarious Learning

    Science.gov (United States)

    Chan, Joanne C. Y.; Lam, Shui-fong

    2008-01-01

    Background: 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. Aim: This study compared the effects of competitive and…

  11. Teaching parents about responsive feeding through a vicarious learning video: A pilot randomized controlled trial

    Science.gov (United States)

    The American Academy of Pediatrics and World Health Organization recommend responsive feeding (RF) to promote healthy eating behaviors in early childhood. This project developed and tested a vicarious learning video to teach parents RF practices. A RF vicarious learning video was developed using com...

  12. Vicarious Trauma: Predictors of Clinicians' Disrupted Cognitions about Self-Esteem and Self-Intimacy

    Science.gov (United States)

    Way, Ineke; VanDeusen, Karen; Cottrell, Tom

    2007-01-01

    This study examined vicarious trauma in clinicians who provide sexual abuse treatment (N = 383). A random sample of clinical members from the Association for the Treatment of Sexual Abusers and American Professional Society on the Abuse of Children were surveyed. Vicarious trauma was measured using the Trauma Stress Institute Belief Scale…

  13. Preventing Vicarious Trauma: What Counselors Should Know when Working with Trauma Survivors

    Science.gov (United States)

    Trippany, Robyn L.; Kress, Victoria E. White; Wilcoxon, S. Allen

    2004-01-01

    Counselors in all settings work with clients who are survivors of trauma. Vicarious trauma, or counselors developing trauma reactions secondary to exposure to clients' traumatic experiences, is not uncommon. The purpose of this article is to describe vicarious trauma and summarize the recent research literature related to this construct. The…

  14. Landsat-8 Thermal Infrared Sensor (TIRS) Vicarious Radiometric Calibration

    Science.gov (United States)

    Barsi, Julia A.; Shott, John R.; Raqueno, Nina G.; Markham, Brian L.; Radocinski, Robert G.

    2014-01-01

    Launched in February 2013, the Landsat-8 carries on-board the Thermal Infrared Sensor (TIRS), a two-band thermal pushbroom imager, to maintain the thermal imaging capability of the Landsat program. The TIRS bands are centered at roughly 10.9 and 12 micrometers (Bands 10 and 11 respectively). They have 100 m spatial resolution and image coincidently with the Operational Land Imager (OLI), also on-board Landsat-8. The TIRS instrument has an internal calibration system consisting of a variable temperature blackbody and a special viewport with which it can see deep space; a two point calibration can be performed twice an orbit. Immediately after launch, a rigorous vicarious calibration program was started to validate the absolute calibration of the system. The two vicarious calibration teams, NASA/Jet Propulsion Laboratory (JPL) and the Rochester Institute of Technology (RIT), both make use of buoys deployed on large water bodies as the primary monitoring technique. RIT took advantage of cross-calibration opportunity soon after launch when Landsat-8 and Landsat-7 were imaging the same targets within a few minutes of each other to perform a validation of the absolute calibration. Terra MODIS is also being used for regular monitoring of the TIRS absolute calibration. The buoy initial results showed a large error in both bands, 0.29 and 0.51 W/sq m·sr·micrometers or -2.1 K and -4.4 K at 300 K in Band 10 and 11 respectively, where TIRS data was too hot. A calibration update was recommended for both bands to correct for a bias error and was implemented on 3 February 2014 in the USGS/EROS processing system, but the residual variability is still larger than desired for both bands (0.12 and 0.2 W/sq m·sr·micrometers or 0.87 and 1.67 K at 300 K). Additional work has uncovered the source of the calibration error: out-of-field stray light. While analysis continues to characterize the stray light contribution, the vicarious calibration work proceeds. The additional data have

  15. Vicarious liability and criminal prosecutions for regulatory offences.

    Science.gov (United States)

    Freckelton, Ian

    2006-08-01

    The parameters of vicarious liability of corporations for the conduct of their employees, especially in the context of provisions that criminalise breaches of regulatory provisions, are complex. The decision of Bell J in ABC Developmental Learning Centres Pty Ltd v Wallace [2006] VSC 171 raises starkly the potential unfairness of an approach which converts criminal liability of corporations too readily into absolute liability, irrespective of the absence of any form of proven culpability. The author queries whether fault should not be brought back in some form to constitute a determinant of criminal liability for corporations.

  16. Landsat-8 Thermal Infrared Sensor (TIRS Vicarious Radiometric Calibration

    Directory of Open Access Journals (Sweden)

    Julia A. Barsi

    2014-11-01

    Full Text Available Launched in February 2013, the Landsat-8 carries on-board the Thermal Infrared Sensor (TIRS, a two-band thermal pushbroom imager, to maintain the thermal imaging capability of the Landsat program. The TIRS bands are centered at roughly 10.9 and 12 μm (Bands 10 and 11 respectively. They have 100 m spatial resolution and image coincidently with the Operational Land Imager (OLI, also on-board Landsat-8. The TIRS instrument has an internal calibration system consisting of a variable temperature blackbody and a special viewport with which it can see deep space; a two point calibration can be performed twice an orbit. Immediately after launch, a rigorous vicarious calibration program was started to validate the absolute calibration of the system. The two vicarious calibration teams, NASA/Jet Propulsion Laboratory (JPL and the Rochester Institute of Technology (RIT, both make use of buoys deployed on large water bodies as the primary monitoring technique. RIT took advantage of cross-calibration opportunity soon after launch when Landsat-8 and Landsat-7 were imaging the same targets within a few minutes of each other to perform a validation of the absolute calibration. Terra MODIS is also being used for regular monitoring of the TIRS absolute calibration. The buoy initial results showed a large error in both bands, 0.29 and 0.51 W/m2·sr·μm or −2.1 K and −4.4 K at 300 K in Band 10 and 11 respectively, where TIRS data was too hot. A calibration update was recommended for both bands to correct for a bias error and was implemented on 3 February 2014 in the USGS/EROS processing system, but the residual variability is still larger than desired for both bands (0.12 and 0.2 W/m2·sr·μm or 0.87 and 1.67 K at 300 K. Additional work has uncovered the source of the calibration error: out-of-field stray light. While analysis continues to characterize the stray light contribution, the vicarious calibration work proceeds. The additional data have not changed

  17. Vicarious substitution in the literary work of Shusaku Endō : On fools, animals, objects and doubles

    NARCIS (Netherlands)

    Coenradie, S.|info:eu-repo/dai/nl/328202711

    2016-01-01

    This research systematically examines the theme of vicarious substitution in Shūsaku Endō’s literary work. It aims at enriching the traditional concepts of vicarious substitution. This study results in the following typology of vicarious substituion in Endo's literature: Christ-figures, including

  18. Information about the model's unconditioned stimulus and response in vicarious classical conditioning.

    Science.gov (United States)

    Hygge, S

    1976-06-01

    Four groups with 16 observers each participated in a differential, vicarious conditioning experiment with skin conductance responses as the dependent variable. The information available to the observer about the model's unconditioned stimulus and response was varied in a 2 X 2 factorial design. Results clearly showed that information about the model's unconditioned stimulus (a high or low dB level) was not necessary for vicarious instigation, but that information about the unconditioned response (a high or low emotional aversiveness) was necessary. Data for conditioning of responses showed almost identical patterns to those for vicarious instigation. To explain the results, a distinction between factors necessary for the development and elicitation of vicariously instigated responses was introduced, and the effectiveness of information about the model's response on the elicitation of vicariously instigated responses was considered in terms of an expansion of Bandura's social learning theory.

  19. Effect of vicarious fear learning on children's heart rate responses and attentional bias for novel animals.

    Science.gov (United States)

    Reynolds, Gemma; Field, Andy P; Askew, Chris

    2014-10-01

    Research with children has shown that vicarious learning can result in changes to 2 of Lang's (1968) 3 anxiety response systems: subjective report and behavioral avoidance. The current study extended this research by exploring the effect of vicarious learning on physiological responses (Lang's final response system) and attentional bias. The study used Askew and Field's (2007) vicarious learning procedure and demonstrated fear-related increases in children's cognitive, behavioral, and physiological responses. Cognitive and behavioral changes were retested 1 week and 1 month later, and remained elevated. In addition, a visual search task demonstrated that fear-related vicarious learning creates an attentional bias for novel animals, which is moderated by increases in fear beliefs during learning. The findings demonstrate that vicarious learning leads to lasting changes in all 3 of Lang's anxiety response systems and is sufficient to create attentional bias to threat in children. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  20. Risk of vicarious trauma in nursing research: a focused mapping review and synthesis.

    Science.gov (United States)

    Taylor, Julie; Bradbury-Jones, Caroline; Breckenridge, Jenna P; Jones, Christine; Herber, Oliver Rudolf

    2016-10-01

    To provide a snapshot of how vicarious trauma is considered within the published nursing research literature. Vicarious trauma (secondary traumatic stress) has been the focus of attention in nursing practice for many years. The most pertinent areas to invoke vicarious trauma in research have been suggested as abuse/violence and death/dying. What is not known is how researchers account for the risks of vicarious trauma in research. Focused mapping review and synthesis. Empirical studies meeting criteria for abuse/violence or death/dying in relevant Scopus ranked top nursing journals (n = 6) January 2009 to December 2014. Relevant papers were scrutinised for the extent to which researchers discussed the risk of vicarious trauma. Aspects of the studies were mapped systematically to a pre-defined template, allowing patterns and gaps in authors' reporting to be determined. These were synthesised into a coherent profile of current reporting practices and from this, a new conceptualisation seeking to anticipate and address the risk of vicarious trauma was developed. Two thousand five hundred and three papers were published during the review period, of which 104 met the inclusion criteria. Studies were distributed evenly by method (52 qualitative; 51 quantitative; one mixed methods) and by focus (54 abuse/violence; 50 death/dying). The majority of studies (98) were carried out in adult populations. Only two papers reported on vicarious trauma. The conceptualisation of vicarious trauma takes account of both sensitivity of the substantive data collected, and closeness of those involved with the research. This might assist researchers in designing ethical and protective research and foreground the importance of managing risks of vicarious trauma. Vicarious trauma is not well considered in research into clinically important topics. Our proposed framework allows for consideration of these so that precautionary measures can be put in place to minimise harm to staff. © 2016

  1. A grounded theory exploration of undergraduate experiences of vicarious unemployment.

    Science.gov (United States)

    Thompson, Mindi N; Nitzarim, Rachel S; Her, Pa; Dahling, Jason J

    2013-07-01

    The experiences of vicarious unemployment (VU) among 17 undergraduate student participants who had a primary caregiver who was involuntarily unemployed were explored using grounded theory (Charmaz, 2006; Glaser & Strauss, 1967). Data from semistructured interviews with 15 women and 2 men revealed the nuanced nature of experiences with unemployment among those who experience it vicariously. Struggles related to increased family stress and experiences with stigma were common across participants. As participants reflected upon these challenges, they both lamented the costs associated with the struggles and expressed appreciation for the lessons that they have learned. They emerged from their VU experiences with increased financial and job market awareness, which informed their hope for a life that is free from the struggles endured in their families. Participants expressed confidence in their ability to cultivate financial security for their own families, stable employment, and opportunities to pursue work that will allow them to give back to others. Implications for counseling and directions for future research are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  2. Testing hypotheses of earthquake occurrence

    Science.gov (United States)

    Kagan, Y. Y.; Jackson, D. D.; Schorlemmer, D.; Gerstenberger, M.

    2003-12-01

    We present a relatively straightforward likelihood method for testing those earthquake hypotheses that can be stated as vectors of earthquake rate density in defined bins of area, magnitude, and time. We illustrate the method as it will be applied to the Regional Earthquake Likelihood Models (RELM) project of the Southern California Earthquake Center (SCEC). Several earthquake forecast models are being developed as part of this project, and additional contributed forecasts are welcome. Various models are based on fault geometry and slip rates, seismicity, geodetic strain, and stress interactions. We would test models in pairs, requiring that both forecasts in a pair be defined over the same set of bins. Thus we offer a standard "menu" of bins and ground rules to encourage standardization. One menu category includes five-year forecasts of magnitude 5.0 and larger. Forecasts would be in the form of a vector of yearly earthquake rates on a 0.05 degree grid at the beginning of the test. Focal mechanism forecasts, when available, would be also be archived and used in the tests. The five-year forecast category may be appropriate for testing hypotheses of stress shadows from large earthquakes. Interim progress will be evaluated yearly, but final conclusions would be made on the basis of cumulative five-year performance. The second category includes forecasts of earthquakes above magnitude 4.0 on a 0.05 degree grid, evaluated and renewed daily. Final evaluation would be based on cumulative performance over five years. Other types of forecasts with different magnitude, space, and time sampling are welcome and will be tested against other models with shared characteristics. All earthquakes would be counted, and no attempt made to separate foreshocks, main shocks, and aftershocks. Earthquakes would be considered as point sources located at the hypocenter. For each pair of forecasts, we plan to compute alpha, the probability that the first would be wrongly rejected in favor of

  3. Vicarious pain experiences while observing another in pain: an experimental approach

    Directory of Open Access Journals (Sweden)

    Sophie eVandenbroucke

    2013-06-01

    Full Text Available Objective: This study aimed at developing an experimental paradigm to assess vicarious pain experiences. We further explored the putative moderating role of observer’s characteristics such as hypervigilance for pain and dispositional empathy. Methods: Two experiments are reported using a similar procedure. Undergraduate students were selected based upon whether they reported vicarious pain in daily life, and categorized into a pain responder group or a comparison group. Participants were presented a series of videos showing hands being pricked whilst receiving occasionally pricking (electrocutaneous stimuli themselves. In congruent trials, pricking and visual stimuli were applied to the same spatial location. In incongruent trials, pricking and visual stimuli were in the opposite spatial location. Participants were required to report on which location they felt a pricking sensation. Of primary interest was the effect of viewing another in pain upon vicarious pain errors, i.e., the number of trials in which an illusionary sensation was reported. Furthermore, we explored the effect of individual differences in hypervigilance to pain, dispositional empathy and the rubber hand illusion (RHI upon vicarious pain errors. Results: Results of both experiments indicated that the number of vicarious pain errors was overall low. In line with expectations, the number of vicarious pain errors was higher in the pain responder group than in the comparison group. Self-reported hypervigilance for pain lowered the probability of reporting vicarious pain errors in the pain responder group, but dispositional empathy and the RHI did not. Conclusion: Our paradigm allows measuring vicarious pain experiences in students. However, the prevalence of vicarious experiences of pain is low, and only a small percentage of participants display the phenomenon. It remains however unknown which variables affect its occurrence.

  4. Vicarious emotional experience and emotional expression in group psychotherapy.

    Science.gov (United States)

    Rosner, R; Beutler, L E; Daldrup, R J

    2000-01-01

    Emotional arousal is a key concept in most theories of change. To be able to understand the role of emotional expression better, two treatments, cognitive therapy (CT) and focused expressive psychotherapy (FEP; a manualized form of Gestalt therapy), with opposite process assumptions about the expression of emotions were compared. Additionally vicarious emotional experience in the sense of an underlying emotional contagion was examined. Clients suffering from major depression were rated for the expression of emotion in three randomly selected sessions of a 20-session treatment course. While the types of emotions generally experienced by CT clients and FEP clients did not differ significantly, differences in the subgroups of active and observing-group members were found. This indicated that the process assumptions made by the respective treatments were only valid for the actively participating clients and not for the observing group members. Emotional contagion as a process was not supported.

  5. Vicarious traumatization and coping in medical students: a pilot study.

    Science.gov (United States)

    Al-Mateen, Cheryl S; Linker, Julie A; Damle, Neha; Hupe, Jessica; Helfer, Tamara; Jessick, Veronica

    2015-02-01

    This study explored the impact of traumatic experiences on medical students during their clerkships. Medical students completed an anonymous online survey inquiring about traumatic experiences on required clerkships during their third year of medical school, including any symptoms they may have experienced as well as coping strategies they may have used. Twenty-six percent of students reported experiencing vicarious traumatization (VT) during their third year of medical school. The experience of VT in medical students is relevant to medical educators, given that the resulting symptoms may impact student performance and learning as well as ongoing well-being. Fifty percent of the students who experienced VT in this study did so on the psychiatry clerkship. It is important for psychiatrists to recognize that this is a potential risk for students in order to increase the likelihood that appropriate supports are provided.

  6. Vicarious traumatization in the work with survivors of childhood trauma.

    Science.gov (United States)

    Crothers, D

    1995-04-01

    1. Persons working with victims of childhood trauma may experience traumatic countertransference and vicarious traumatization. After hearing a patient's trauma story, which is a necessary part of childhood trauma therapy, staff may experience post-traumatic stress disorder, imagery associated with the patient's story and the same disruptions in relationships as the patient. 2. During the first 6 months of working with survivors of childhood trauma, common behaviors of staff members were identified, including a lack of attention, poor work performance, medication errors, sick calls, treatment errors, irreverence, hypervigilance, and somatic complaints. 3. Staff working with victims of childhood trauma can obtain the necessary staff support through team support, in traumatic events, and in a leadership role.

  7. Secondary traumatic stress and vicarious trauma: a validational study.

    Science.gov (United States)

    Jenkins, Sharon Rae; Baird, Stephanie

    2002-10-01

    Vicarious trauma (VT) and secondary traumatic stress (STS) or compassion fatigue both describe effects of working with traumatized persons on therapists. Despite conceptual similarities, their emphases differ: cognitive schemas vs. posttraumatic symptoms and burnout, respectively. The TSI Belief Scale (TSI-BSL) measures VT; the Compassion Fatigue Self-Test (CFST) for Psychotherapists measures STS. Neither has substantial psychometric evidence yet, nor has their association been studied. Results for 99 sexual assault and domestic violence counselors show concurrent validity between TSI-BSL and CFST, moderate convergence with burnout but useful discrimination, and strong convergence with general distress, but adequate independent shared variance. Counselors with interpersonal trauma histories scored higher on CFST, but not TSI-BSL or burnout, consistent with the CFST's emphasis on trauma symptomatology.

  8. Predictive hypotheses are ineffectual in resolving complex biochemical systems.

    Science.gov (United States)

    Fry, Michael

    2018-03-20

    Scientific hypotheses may either predict particular unknown facts or accommodate previously-known data. Although affirmed predictions are intuitively more rewarding than accommodations of established facts, opinions divide whether predictive hypotheses are also epistemically superior to accommodation hypotheses. This paper examines the contribution of predictive hypotheses to discoveries of several bio-molecular systems. Having all the necessary elements of the system known beforehand, an abstract predictive hypothesis of semiconservative mode of DNA replication was successfully affirmed. However, in defining the genetic code whose biochemical basis was unclear, hypotheses were only partially effective and supplementary experimentation was required for its conclusive definition. Markedly, hypotheses were entirely inept in predicting workings of complex systems that included unknown elements. Thus, hypotheses did not predict the existence and function of mRNA, the multiple unidentified components of the protein biosynthesis machinery, or the manifold unknown constituents of the ubiquitin-proteasome system of protein breakdown. Consequently, because of their inability to envision unknown entities, predictive hypotheses did not contribute to the elucidation of cation theories remained the sole instrument to explain complex bio-molecular systems, the philosophical question of alleged advantage of predictive over accommodative hypotheses became inconsequential.

  9. Hippocampus, delay discounting, and vicarious trial-and-error.

    Science.gov (United States)

    Bett, David; Murdoch, Lauren H; Wood, Emma R; Dudchenko, Paul A

    2015-05-01

    In decision-making, an immediate reward is usually preferred to a delayed reward, even if the latter is larger. We tested whether the hippocampus is necessary for this form of temporal discounting, and for vicarious trial-and-error at the decision point. Rats were trained on a recently developed, adjustable delay-discounting task (Papale et al. (2012) Cogn Affect Behav Neurosci 12:513-526), which featured a choice between a small, nearly immediate reward, and a larger, delayed reward. Rats then received either hippocampus or sham lesions. Animals with hippocampus lesions adjusted the delay for the larger reward to a level similar to that of sham-lesioned animals, suggesting a similar valuation capacity. However, the hippocampus lesion group spent significantly longer investigating the small and large rewards in the first part of the sessions, and were less sensitive to changes in the amount of reward in the large reward maze arm. Both sham- and hippocampus-lesioned rats showed a greater amount of vicarious trial-and-error on trials in which the delay was adjusted. In a nonadjusting version of the delay discounting task, animals with hippocampus lesions showed more variability in their preference for a larger reward that was delayed by 10 s compared with sham-lesioned animals. To verify the lesion behaviorally, rat were subsequently trained on a water maze task, and rats with hippocampus lesions were significantly impaired compared with sham-lesioned animals. The findings on the delay discounting tasks suggest that damage to the hippocampus may impair the detection of reward magnitude. © 2014 Wiley Periodicals, Inc.

  10. Vicariance or long-distance dispersal: historical biogeography of the pantropical subfamily Chrysophylloideae (Sapotaceae)

    Czech Academy of Sciences Publication Activity Database

    Bartish, Igor; Antonelli, A.; Richardson, J. E.; Swenson, U.

    2011-01-01

    Roč. 38, č. 1 (2011), s. 177-190 ISSN 0305-0270 Institutional research plan: CEZ:AV0Z60050516 Keywords : molecular dating * Neotropics * vicariance Subject RIV: EF - Botanics Impact factor: 4.544, year: 2011

  11. Reductions in Children's Vicariously Learnt Avoidance and Heart Rate Responses Using Positive Modeling.

    Science.gov (United States)

    Reynolds, Gemma; Field, Andy P; Askew, Chris

    2016-03-23

    Recent research has indicated that vicarious learning can lead to increases in children's fear beliefs and avoidance preferences for stimuli and that these fear responses can subsequently be reversed using positive modeling (counterconditioning). The current study investigated children's vicariously acquired avoidance behavior, physiological responses (heart rate), and attentional bias for stimuli and whether these could also be reduced via counterconditioning. Ninety-six (49 boys, 47 girls) 7- to 11-year-olds received vicarious fear learning for novel stimuli and were then randomly assigned to a counterconditioning, extinction, or control group. Fear beliefs and avoidance preferences were measured pre- and post-learning, whereas avoidance behavior, heart rate, and attentional bias were all measured post-learning. Control group children showed increases in fear beliefs and avoidance preferences for animals seen in vicarious fear learning trials. In addition, significantly greater avoidance behavior, heart rate responding, and attentional bias were observed for these animals compared to a control animal. In contrast, vicariously acquired avoidance preferences of children in the counterconditioning group were significantly reduced post-positive modeling, and these children also did not show the heightened heart rate responding to fear-paired animals. Children in the extinction group demonstrated comparable responses to the control group; thus the extinction procedure showed no effect on any fear measures. The findings suggest that counterconditioning with positive modelling can be used as an effective early intervention to reduce the behavioral and physiological effects of vicarious fear learning in childhood.

  12. Assessing hypotheses about nesting site occupancy dynamics

    Science.gov (United States)

    Bled, Florent; Royle, J. Andrew; Cam, Emmanuelle

    2011-01-01

    Hypotheses about habitat selection developed in the evolutionary ecology framework assume that individuals, under some conditions, select breeding habitat based on expected fitness in different habitat. The relationship between habitat quality and fitness may be reflected by breeding success of individuals, which may in turn be used to assess habitat quality. Habitat quality may also be assessed via local density: if high-quality sites are preferentially used, high density may reflect high-quality habitat. Here we assessed whether site occupancy dynamics vary with site surrogates for habitat quality. We modeled nest site use probability in a seabird subcolony (the Black-legged Kittiwake, Rissa tridactyla) over a 20-year period. We estimated site persistence (an occupied site remains occupied from time t to t + 1) and colonization through two subprocesses: first colonization (site creation at the timescale of the study) and recolonization (a site is colonized again after being deserted). Our model explicitly incorporated site-specific and neighboring breeding success and conspecific density in the neighborhood. Our results provided evidence that reproductively "successful'' sites have a higher persistence probability than "unsuccessful'' ones. Analyses of site fidelity in marked birds and of survival probability showed that high site persistence predominantly reflects site fidelity, not immediate colonization by new owners after emigration or death of previous owners. There is a negative quadratic relationship between local density and persistence probability. First colonization probability decreases with density, whereas recolonization probability is constant. This highlights the importance of distinguishing initial colonization and recolonization to understand site occupancy. All dynamics varied positively with neighboring breeding success. We found evidence of a positive interaction between site-specific and neighboring breeding success. We addressed local

  13. Sympathetic pain? A role of poor parasympathetic nervous system engagement in vicarious pain states.

    Science.gov (United States)

    Nazarewicz, Julia; Verdejo-Garcia, Antonio; Giummarra, Melita J

    2015-11-01

    This study investigated the psychophysiological correlates of the subjective experience of vicarious pain; that is, a spontaneous experience of pain when seeing another in pain. Forty-nine healthy, otherwise pain-free individuals aged 18-55 years completed empathy and anxiety questionnaires and were classified into three groups: vicarious responders with high anxiety (n = 11), vicarious responders with low anxiety (n = 22), and nonresponders (n = 16). Electrophysiological recordings of heart rate variability (HRV) during paced breathing and cognitive stress (serial sevens task) were completed before participants viewed short videos of athletes in states of pain or happiness, taken from Australian League Football matches. Change in beats per minute, relative to neutral scenes, were analyzed for the first 4 s after onset of the painful or happy event. Anxious responders had lower HF-HRV than both other groups, implicating poor parasympathetic regulation specific to states of stress. Both vicarious responder groups had elevated HR at the event onset, regardless of valence. After viewing painful injuries, nonanxious vicarious responders showed sustained HR over time, anxious responders showed HR acceleration with a peak at 3 s after the injury onset, and nonresponders showed a pattern of marked HR deceleration. These findings suggest that vicarious pain in anxious responders is associated with poorly regulated sympathetic arousal via insufficient inhibitory parasympathetic activity, whereas nonanxious persons show sustained arousal. Clearly, multiple mechanisms in the central and peripheral nervous system must play a role in vicarious pain states, and the different manifestations are likely to lead to very different behavioral consequences. © 2015 Society for Psychophysiological Research.

  14. Inhibition of vicariously learned fear in children using positive modeling and prior exposure.

    Science.gov (United States)

    Askew, Chris; Reynolds, Gemma; Fielding-Smith, Sarah; Field, Andy P

    2016-02-01

    One of the challenges to conditioning models of fear acquisition is to explain how different individuals can experience similar learning events and only some of them subsequently develop fear. Understanding factors moderating the impact of learning events on fear acquisition is key to understanding the etiology and prevention of fear in childhood. This study investigates these moderators in the context of vicarious (observational) learning. Two experiments tested predictions that the acquisition or inhibition of fear via vicarious learning is driven by associative learning mechanisms similar to direct conditioning. In Experiment 1, 3 groups of children aged 7 to 9 years received 1 of 3 inhibitive information interventions-psychoeducation, factual information, or no information (control)-prior to taking part in a vicarious fear learning procedure. In Experiment 2, 3 groups of children aged 7 to 10 years received 1 of 3 observational learning interventions-positive modeling (immunization), observational familiarity (latent inhibition), or no prevention (control)-before vicarious fear learning. Results indicated that observationally delivered manipulations inhibited vicarious fear learning, while preventions presented via written information did not. These findings confirm that vicarious learning shares some of the characteristics of direct conditioning and can explain why not all individuals will develop fear following a vicarious learning event. They also suggest that the modality of inhibitive learning is important and should match the fear learning pathway for increased chances of inhibition. Finally, the results demonstrate that positive modeling is likely to be a particularly effective method for preventing fear-related observational learning in children. (c) 2016 APA, all rights reserved).

  15. Glacial-driven vicariance in the amphipod Gammarus duebeni.

    Science.gov (United States)

    Krebes, L; Blank, M; Jürss, K; Zettler, M L; Bastrop, R

    2010-02-01

    We have examined the genetic diversity using mitochondrial COI and ND2 sequence data from 306 specimens of the amphi-Atlantic-distributed amphipod Gammarus duebeni. Marine populations from the Atlantic Ocean, the Baltic and North Sea, as well as freshwater populations from Ireland, Cornwall and Brittany were analysed. G. duebeni is a complex of five allopatric lineages. Freshwater populations result from multiple invasions of marine ancestors, represented by distinct lineages. We interpret the recent distribution of lineages as the outcome of a series of spatio-temporal vicariant events caused by Pleistocene glaciations and sea level changes. The freshwater lineages are therefore regarded as 'glacial relicts'. Furthermore, inter-specific competition with, for example, Gammarus pulex (which is absent in Ireland and western Brittany) may be another important determinant in the distribution of freshwater G. duebeni. In Ireland and Brittany, three freshwater refugia are suggested. The significantly limited gene flow detected among marine populations is more likely due to inter-specific competition than to salinity. The G. duebeni-complex represents a model system for the study of allopatric speciation accompanied by major habitat shifts. The pattern of spatio-temporal origins of the freshwater entities we describe here provides an excellent system for investigating evolutionary adaptations to the freshwater environment. Our data did not confirm the presently used subspecies classification but are only preliminary in the absence of nuclear genetic analyses. Copyright (c) 2009. Published by Elsevier Inc.

  16. Development of vicarious trial-and-error behavior in odor discrimination learning in the rat: relation to hippocampal function?

    Science.gov (United States)

    Hu, D; Griesbach, G; Amsel, A

    1997-06-01

    Previous work from our laboratory has suggested that hippocampal electrolytic lesions result in a deficit in simultaneous, black-white discrimination learning and reduce the frequency of vicarious trial-and-error (VTE) at a choice-point. VTE is a term Tolman used to describe the rat's conflict-like behavior, moving its head from one stimulus to the other at a choice point, and has been proposed as a major nonspatial feature of hippocampal function in both visual and olfactory discrimination learning. Simultaneous odor discrimination and VTE behavior were examined at three different ages. The results were that 16-day-old pups made fewer VTEs and learned much more slowly than 30- and 60-day-olds, a finding in accord with levels of hippocampal maturity in the rat.

  17. NIR- and SWIR-based on-orbit vicarious calibrations for satellite ocean color sensors.

    Science.gov (United States)

    Wang, Menghua; Shi, Wei; Jiang, Lide; Voss, Kenneth

    2016-09-05

    The near-infrared (NIR) and shortwave infrared (SWIR)-based atmospheric correction algorithms are used in satellite ocean color data processing, with the SWIR-based algorithm particularly useful for turbid coastal and inland waters. In this study, we describe the NIR- and two SWIR-based on-orbit vicarious calibration approaches for satellite ocean color sensors, and compare results from these three on-orbit vicarious calibrations using satellite measurements from the Visible Infrared Imaging Radiometer Suite (VIIRS) onboard the Suomi National Polar-orbiting Partnership (SNPP). Vicarious calibration gains for VIIRS spectral bands are derived using the in situ normalized water-leaving radiance nLw(λ) spectra from the Marine Optical Buoy (MOBY) in waters off Hawaii. The SWIR vicarious gains are determined using VIIRS measurements from the South Pacific Gyre region, where waters are the clearest and generally stable. Specifically, vicarious gain sets for VIIRS spectral bands of 410, 443, 486, 551, and 671 nm derived from the NIR method using the NIR 745 and 862 nm bands, the SWIR method using the SWIR 1238 and 1601 nm bands, and the SWIR method using the SWIR 1238 and 2257 nm bands are (0.979954, 0.974892, 0.974685, 0.965832, 0.979042), (0.980344, 0.975344, 0.975357, 0.965531, 0.979518), and (0.980820, 0.975609, 0.975761, 0.965888, 0.978576), respectively. Thus, the NIR-based vicarious calibration gains are consistent with those from the two SWIR-based approaches with discrepancies mostly within ~0.05% from three data processing methods. In addition, the NIR vicarious gains (745 and 862 nm) derived from the two SWIR methods are (0.982065, 1.00001) and (0.981811, 1.00000), respectively, with the difference ~0.03% at the NIR 745 nm band. This is the fundamental basis for the NIR-SWIR combined atmospheric correction algorithm, which has been used to derive improved satellite ocean color products over open oceans and turbid coastal/inland waters. Therefore, a unified

  18. Stimulus fear relevance and the speed, magnitude, and robustness of vicariously learned fear.

    Science.gov (United States)

    Dunne, Güler; Reynolds, Gemma; Askew, Chris

    2017-08-01

    Superior learning for fear-relevant stimuli is typically indicated in the laboratory by faster acquisition of fear responses, greater learned fear, and enhanced resistance to extinction. Three experiments investigated the speed, magnitude, and robustness of UK children's (6-10 years; N = 290; 122 boys, 168 girls) vicariously learned fear responses for three types of stimuli. In two experiments, children were presented with pictures of novel animals (Australian marsupials) and flowers (fear-irrelevant stimuli) alone (control) or together with faces expressing fear or happiness. To determine learning speed the number of stimulus-face pairings seen by children was varied (1, 10, or 30 trials). Robustness of learning was examined via repeated extinction procedures over 3 weeks. A third experiment compared the magnitude and robustness of vicarious fear learning for snakes and marsupials. Significant increases in fear responses were found for snakes, marsupials and flowers. There was no indication that vicarious learning for marsupials was faster than for flowers. Moreover, vicariously learned fear was neither greater nor more robust for snakes compared to marsupials, or for marsupials compared to flowers. These findings suggest that for this age group stimulus fear relevance may have little influence on vicarious fear learning. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Learning to fear a second-order stimulus following vicarious learning.

    Science.gov (United States)

    Reynolds, Gemma; Field, Andy P; Askew, Chris

    2017-04-01

    Vicarious fear learning refers to the acquisition of fear via observation of the fearful responses of others. The present study aims to extend current knowledge by exploring whether second-order vicarious fear learning can be demonstrated in children. That is, whether vicariously learnt fear responses for one stimulus can be elicited in a second stimulus associated with that initial stimulus. Results demonstrated that children's (5-11 years) fear responses for marsupials and caterpillars increased when they were seen with fearful faces compared to no faces. Additionally, the results indicated a second-order effect in which fear-related learning occurred for other animals seen together with the fear-paired animal, even though the animals were never observed with fearful faces themselves. Overall, the findings indicate that for children in this age group vicariously learnt fear-related responses for one stimulus can subsequently be observed for a second stimulus without it being experienced in a fear-related vicarious learning event. These findings may help to explain why some individuals do not recall involvement of a traumatic learning episode in the development of their fear of a specific stimulus.

  20. Specific Vicariance of Two Primeval Lowland Forest Lichen Indicators

    Science.gov (United States)

    Kubiak, Dariusz; Osyczka, Piotr

    2017-06-01

    To date, the lichens Chrysothrix candelaris and Varicellaria hemisphaerica have been classified as accurate primeval lowland forest indicators. Both inhabit particularly valuable remnants of oak-hornbeam forests in Europe, but tend toward a specific kind of vicariance on a local scale. The present study was undertaken to determine habitat factors responsible for this phenomenon and verify the indicative and conservation value of these lichens. The main spatial and climatic parameters that, along with forest structure, potentially affect their distribution patterns and abundance were analysed in four complexes with typical oak-hornbeam stands in NE Poland. Fifty plots of 400 m2 each were chosen for detailed examination of stand structure and epiphytic lichens directly associated with the indicators. The study showed that the localities of the two species barely overlap within the same forest community in a relatively small geographical area. The occurrence of Chrysothrix candelaris depends basically only on microhabitat space provided by old oaks and its role as an indicator of the ecological continuity of habitat is limited. Varicellaria hemisphaerica is not tree specific but a sufficiently high moisture of habitat is essential for the species and it requires forests with high proportion of deciduous trees in a wide landscape scale. Local landscape-level habitat continuity is more important for this species than the current age of forest stand. Regardless of the indicative value, localities of both lichens within oak-hornbeam forests deserve the special protection status since they form unique assemblages of exclusive epiphytes, including those with high conservation value.

  1. Specific Vicariance of Two Primeval Lowland Forest Lichen Indicators.

    Science.gov (United States)

    Kubiak, Dariusz; Osyczka, Piotr

    2017-06-01

    To date, the lichens Chrysothrix candelaris and Varicellaria hemisphaerica have been classified as accurate primeval lowland forest indicators. Both inhabit particularly valuable remnants of oak-hornbeam forests in Europe, but tend toward a specific kind of vicariance on a local scale. The present study was undertaken to determine habitat factors responsible for this phenomenon and verify the indicative and conservation value of these lichens. The main spatial and climatic parameters that, along with forest structure, potentially affect their distribution patterns and abundance were analysed in four complexes with typical oak-hornbeam stands in NE Poland. Fifty plots of 400 m 2 each were chosen for detailed examination of stand structure and epiphytic lichens directly associated with the indicators. The study showed that the localities of the two species barely overlap within the same forest community in a relatively small geographical area. The occurrence of Chrysothrix candelaris depends basically only on microhabitat space provided by old oaks and its role as an indicator of the ecological continuity of habitat is limited. Varicellaria hemisphaerica is not tree specific but a sufficiently high moisture of habitat is essential for the species and it requires forests with high proportion of deciduous trees in a wide landscape scale. Local landscape-level habitat continuity is more important for this species than the current age of forest stand. Regardless of the indicative value, localities of both lichens within oak-hornbeam forests deserve the special protection status since they form unique assemblages of exclusive epiphytes, including those with high conservation value.

  2. APEX Airborne Imaging Spectrometer Uncertainty Budget and Vicarious Validation Method

    Science.gov (United States)

    Hueni, A.; Woolliams, E.; Schlaepfer, D.; Wulf, H.

    2017-12-01

    ESA's Airborne Imaging Spectrometer APEX (Airborne Prism Experiment) was developed by a Swiss-Belgian consortium and entered its operational phase at the end of 2010 (Schaepman et al. 2015). Work on the sensor model and on propagated uncertainties from the laboratory to the in-flight case has been carried out extensively within the framework of EMRP (European Metrology Research Program) as part of the Metrology for Earth Observation and Climate (MetEOC and MetEOC2). The uncertainty propagation has been implemented in the APEX Calibration Information System (Hueni et al. 2013) and the APEX Level 1 processor (Hueni et al. 2009), thus allowing the operational computation of uncertainties for any at-sensor radiance APEX imaging cube. This fosters a better understanding and aids evaluation of the results of vicarious validation using spectral ground control points stored in the spectral information system SPECCHIO (Hueni et al. 2016). The presented work ultimately benefits the production of traceable higher-level products and enables sensitivity analyses of models, e.g. 3D canopy simulations, parameterised by APEX radiances. Hueni, A., Biesemans, J., Meuleman, K., Dell'Endice, F., Schläpfer, D., et al (2009). "Structure, Components and Interfaces of the Airborne Prism Experiment (APEX) Processing and Archiving Facility." IEEE TGRS 47(1): 29-43. Hueni, A., Damm, A., Kneubuehler, M., Schläpfer, D. and Schaepman, M. (2016). "Field and Airborne Spectroscopy Cross-Validation - Some Considerations." IEEE JSTARS 10(3): 1117 - 1135. Hueni, A., Lenhard, K., Baumgartner, A. and Schaepman, M. (2013). "The APEX (Airborne Prism Experiment - Imaging Spectrometer) Calibration Information System." IEEE TGRS 51(11): 5169-5180. Schaepman, M., Jehle, M., Hueni, A., D'Odorico, P., Damm, A., et al (2015). "Advanced radiometry measurements and Earth science applications with the Airborne Prism Experiment (APEX)." Remote Sensing of Environment 158: 207-219.

  3. The Deep-Level-Reasoning-Question Effect: The Role of Dialogue and Deep-Level-Reasoning Questions during Vicarious Learning

    Science.gov (United States)

    Craig, Scotty D.; Sullins, Jeremiah; Witherspoon, Amy; Gholson, Barry

    2006-01-01

    We investigated the impact of dialogue and deep-level-reasoning questions on vicarious learning in 2 studies with undergraduates. In Experiment 1, participants learned material by interacting with AutoTutor or by viewing 1 of 4 vicarious learning conditions: a noninteractive recorded version of the AutoTutor dialogues, a dialogue with a…

  4. Exploring hypotheses in attitude control fault diagnosis

    Science.gov (United States)

    Bell, Benjamin

    1987-01-01

    A system which analyzes telemetry and evaluates hypotheses to explain any anomalies that are observed is described. Results achieved from a sample set of failure cases are presented, followed by a brief discussion of the benefits derived from this approach.

  5. Quantitative linking hypotheses for infant eye movements.

    Directory of Open Access Journals (Sweden)

    Daniel Yurovsky

    Full Text Available The study of cognitive development hinges, largely, on the analysis of infant looking. But analyses of eye gaze data require the adoption of linking hypotheses: assumptions about the relationship between observed eye movements and underlying cognitive processes. We develop a general framework for constructing, testing, and comparing these hypotheses, and thus for producing new insights into early cognitive development. We first introduce the general framework--applicable to any infant gaze experiment--and then demonstrate its utility by analyzing data from a set of experiments investigating the role of attentional cues in infant learning. The new analysis uncovers significantly more structure in these data, finding evidence of learning that was not found in standard analyses and showing an unexpected relationship between cue use and learning rate. Finally, we discuss general implications for the construction and testing of quantitative linking hypotheses. MATLAB code for sample linking hypotheses can be found on the first author's website.

  6. Transmitting Trauma: A systematic review of vicarious racism and child health.

    Science.gov (United States)

    Heard-Garris, N J; Cale, M; Camaj, L; Hamati, M C; Dominguez, T P

    2018-02-01

    Racism is a pervasive stressor. Although most research focuses on direct targets, racism can also have unintended victims. Because children's lives are inevitably linked to the experiences of other individuals, and they are in critical phases of development, they are especially vulnerable to such stressors. Despite the growing body of literature on children's direct exposure to racism, little is known about the relationship between vicarious racism (i.e. secondhand exposure to racism) and child health. To examine the state of this literature, we performed a systematic review and screened 1371 articles drawn from 7 databases, with 30 studies meeting inclusion criteria. For these 30, we reviewed research methodology, including conceptualization and measurement of vicarious exposure, sample characteristics, significant associations with child health outcomes, and mediators and/or moderators of those associations. Most studies were published after 2011 in urban areas in the U.S., employed longitudinal designs, and focused on African American populations. Socioemotional and mental health outcomes were most commonly reported with statistically significant associations with vicarious racism. While all studies examined racism indirectly experienced by children, there was no standard definition of vicarious racism used. We organize the findings in a schematic diagram illustrating indirectly-experienced racism and child health outcomes to identify current gaps in the literature and ways in which to bridge those gaps. To further the field, vicarious racism should be uniformly defined and directly measured using psychometrically validated tools. Future studies should consider using children as the informants and follow children into early adulthood to better understand causal mechanisms. Given the recent national exposure to racially-charged events, a deeper understanding of the association between vicarious racism and child health is crucial in fueling research

  7. Effect of Vicarious Fear Learning on Children’s Heart Rate Responses and Attentional Bias for Novel Animals

    Science.gov (United States)

    2014-01-01

    Research with children has shown that vicarious learning can result in changes to 2 of Lang’s (1968) 3 anxiety response systems: subjective report and behavioral avoidance. The current study extended this research by exploring the effect of vicarious learning on physiological responses (Lang’s final response system) and attentional bias. The study used Askew and Field’s (2007) vicarious learning procedure and demonstrated fear-related increases in children’s cognitive, behavioral, and physiological responses. Cognitive and behavioral changes were retested 1 week and 1 month later, and remained elevated. In addition, a visual search task demonstrated that fear-related vicarious learning creates an attentional bias for novel animals, which is moderated by increases in fear beliefs during learning. The findings demonstrate that vicarious learning leads to lasting changes in all 3 of Lang’s anxiety response systems and is sufficient to create attentional bias to threat in children. PMID:25151521

  8. Retroduction, Multiverse Hypotheses and Their Testability

    OpenAIRE

    Stoeger, William R.

    2006-01-01

    The actual existence of collections of universes -- multiverses -- is strongly suggested by leading approaches to quantum cosmology, and has been proposed earlier as an attractive way to explain the apparent fine-tuned character of our universe. But, how can such hypotheses be tested? After briefly discussing the key distinction between possible and really existing multiverses, and the importance of an adequate generating process, we focus on elaborating how multiverse hypotheses can be retro...

  9. Indirect exposure to client trauma and the impact on trainee clinical psychologists: Secondary traumatic stress or vicarious traumatization?

    Science.gov (United States)

    Makadia, Rakhee; Sabin-Farrell, Rachel; Turpin, Graham

    2017-09-01

    The study investigated the relationship between exposure to trauma work and well-being (general psychological distress, trauma symptoms, and disrupted beliefs) in trainee clinical psychologists. It also assessed the contribution of individual and situational factors to well-being. A Web-based survey was employed. The survey comprised the General Health Questionnaire, Secondary Traumatic Stress Scale, Trauma and Attachment Belief Scale, Trauma Screening Questionnaire, and specific questions about exposure to trauma work and other individual and situational factors. The link to the online survey was sent via email to trainee clinical psychologists attending courses throughout the UK RESULTS: Five hundred sixty-four trainee clinical psychologists participated. Most trainees had a caseload of one to two trauma cases in the previous 6 months; the most common trauma being sexual abuse. Exposure to trauma work was not related to general psychological distress or disrupted beliefs but was a significant predictor of trauma symptoms. Situational factors contributed to the variance in trauma symptoms; level of stress of clinical work and quality of trauma training were significant predictors of trauma symptoms. Individual and situational factors were also found to be significant predictors of general psychological distress and disrupted beliefs. This study provides support for secondary traumatic stress but lacks evidence to support belief changes in vicarious traumatization or a relationship between exposure to trauma work and general psychological distress. The measurement and validity of vicarious traumatization is discussed along with clinical, theoretical implications, and suggestions for future research. Secondary traumatic stress is a potential risk for trainee clinical psychologists. Training courses should (a) focus on quality of trauma training as it may be protective; (b) advocate coping strategies to reduce stress of clinical work, as the level of stress of

  10. F v Minister of Safety and Security: Vicarious liability and state ...

    African Journals Online (AJOL)

    The Constitutional Court judgement in F v Minister of Safety and Security 1 is a ground-breaking judgement in two important respects: firstly, it finally does away with the fiction that an employee acts within the course and scope of her employment in the so-called deviation cases in the law of vicarious liability, and secondly it ...

  11. Coping with Vicarious Trauma in the Aftermath of a Natural Disaster

    Science.gov (United States)

    Smith, Lauren E.; Bernal, Darren R.; Schwartz, Billie S.; Whitt, Courtney L.; Christman, Seth T.; Donnelly, Stephanie; Wheatley, Anna; Guillaume, Casta; Nicolas, Guerda; Kish, Jonathan; Kobetz, Erin

    2014-01-01

    This study documents the vicarious psychological impact of the 2010 earthquake in Haiti on Haitians living in the United States. The role of coping resources--family, religious, and community support--was explored. The results highlight the importance of family and community as coping strategies to manage such trauma.

  12. Vicarious Learning and Reduction of Fear in Children via Adult and Child Models.

    Science.gov (United States)

    Dunne, Güler; Askew, Chris

    2017-06-01

    Children can learn to fear stimuli vicariously, by observing adults' or peers' responses to them. Given that much of school-age children's time is typically spent with their peers, it is important to establish whether fear learning from peers is as effective or robust as learning from adults, and also whether peers can be successful positive models for reducing fear. During a vicarious fear learning procedure, children (6 to 10 years; N = 60) were shown images of novel animals together with images of adult or peer faces expressing fear. Later they saw their fear-paired animal again together with positive emotional adult or peer faces. Children's fear beliefs and avoidance for the animals increased following vicarious fear learning and decreased following positive vicarious counterconditioning. There was little evidence of differences in learning from adults and peers, demonstrating that for this age group peer models are effective models for both fear acquisition and reduction. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  13. Secondary Traumatic Stress, Vicarious Trauma, and the Supervisory Working Alliance in Counselor Trainees

    Science.gov (United States)

    Wood, Sara LaRose

    2011-01-01

    This study examined the relationship between secondary traumatic stress (STS), vicarious trauma (VT), and the supervisory working alliance (SWA) with the faculty supervisor among counselor trainees (N = 86). The primary purpose of this study was to determine if the SWA and demographic influence STS and VT. Two correlations were conducted to assess…

  14. Vicarious Racism: A Qualitative Analysis of Experiences with Secondhand Racism in Graduate Education

    Science.gov (United States)

    Truong, Kimberly A.; Museus, Samuel D.; McGuire, Keon M.

    2016-01-01

    In this article, the authors examine the role of vicarious racism in the experiences of doctoral students of color. The researchers conducted semi-structured individual interviews with 26 doctoral students who self-reported experiencing racism and racial trauma during their doctoral studies. The analysis generated four themes that detail the…

  15. Effects of vicarious pain on self-pain perception: investigating the role of awareness

    Directory of Open Access Journals (Sweden)

    Terrighena EL

    2017-07-01

    Full Text Available Esslin L Terrighena,1,2 Ge Lu,1 Wai Ping Yuen,1 Tatia M C Lee,1–4 Kati Keuper1,2,5 1Department of Psychology, Laboratory of Neuropsychology, The University of Hong Kong, Hong Kong; 2Laboratory of Social Cognitive Affective Neuroscience, The University of Hong Kong, Hong Kong; 3The State Key Laboratory of Brain and Cognitive Sciences, Hong Kong; 4Institute of Clinical Neuropsychology, The University of Hong Kong, Hong Kong; 5Institute for Biomagnetism and Biosignalanalysis, University of Münster, Münster, Germany Abstract: The observation of pain in others may enhance or reduce self-pain, yet the boundary conditions and factors that determine the direction of such effects are poorly understood. The current study set out to show that visual stimulus awareness plays a crucial role in ­determining whether vicarious pain primarily activates behavioral defense systems that enhance pain sensitivity and stimulate withdrawal or appetitive systems that attenuate pain sensitivity and stimulate approach. We employed a mixed factorial design with the between-subject factors exposure time (subliminal vs optimal and vicarious pain (pain vs no pain images, and the within-subject factor session (baseline vs trial to investigate how visual awareness of vicarious pain images affects subsequent self-pain in the cold-pressor test. Self-pain tolerance, intensity and unpleasantness were evaluated in a sample of 77 healthy participants. Results revealed ­significant interactions of exposure time and vicarious pain in all three dependent measures. In the presence of visual awareness (optimal condition, vicarious pain compared to no-pain elicited overall enhanced self-pain sensitivity, indexed by reduced pain tolerance and enhanced ratings of pain intensity and unpleasantness. Conversely, in the absence of visual awareness (subliminal condition, vicarious pain evoked decreased self-pain intensity and unpleasantness while pain tolerance remained unaffected. These

  16. Vicarious learning during simulations: is it more effective than hands-on training?

    Science.gov (United States)

    Stegmann, Karsten; Pilz, Florian; Siebeck, Matthias; Fischer, Frank

    2012-10-01

    Doctor-patient communication skills are often fostered by using simulations with standardised patients (SPs). The efficiency of such experiences is greater if student observers learn at least as much from the simulation as do students who actually interact with the patient. This study aimed to investigate whether the type of simulation-based learning (learning by doing versus vicarious learning) and the order in which these activities are carried out (learning by doing → vicarious learning versus vicarious learning → learning by doing) have any effect on the acquisition of knowledge on effective doctor-patient communication strategies. In addition, we wished to examine the extent to which an observation script and a feedback formulation script affect knowledge acquisition in this domain. The sample consisted of 200 undergraduate medical students (126 female, 74 male). They participated in two separate simulation sessions, each of which was 30 minutes long and was followed by a collaborative peer feedback phase. Half of the students first performed (learning by doing) and then observed (vicarious learning) the simulation, and the other half participated in the reverse order. Knowledge of doctor-patient communication was measured before, between and after the simulations. Vicarious learning led to greater knowledge of doctor-patient communication scores than learning by doing. The order in which vicarious learning was experienced had no influence. The inclusion of an observation script also enabled significantly greater learning in students to whom this script was given compared with students who were not supported in this way, but the presence of a feedback script had no effect. Students appear to learn at least as much, if not more, about doctor-patient communication by observing their peers interact with SPs as they do from interacting with SPs themselves. Instructional support for observing simulations in the form of observation scripts facilitates both

  17. Hypotheses about the psychological benefits of horses.

    Science.gov (United States)

    Kendall, Elizabeth; Maujean, Annick; Pepping, Christopher A; Wright, John J

    2014-01-01

    In the last few decades, therapeutic horse-riding has become recognized as a progressive form of therapy, particularly for people with disabilities. Although there is a substantial amount of literature that supports the physical benefit of therapeutic riding, only anecdotal evidence exists in relation to its psychological benefits. The purpose of this article is to develop hypotheses about the mechanisms by which therapeutic riding might have a beneficial psychological effect. These hypotheses can then be tested, leading to a more detailed knowledge base. PsychINFO, MEDLINE, PROQUEST, Scopus, Web of Science, and CINAHL. Data sources were searched for studies that (a) were related to the psychological effects of therapeutic horse-riding, (b) focused exclusively on therapeutic horse-riding, (c) described, explicitly or implicitly, the mechanism by which therapeutic riding had a beneficial psychological effect. Studies were limited to those published between 2008 and 2012. Data were extracted by two authors independently. Thirty articles met the inclusion criteria. Three potential hypotheses emerged from the literature, namely, (1) the psychological benefits of therapeutic riding are actually unrelated to the horse, (2) the horse provides a particularly positive context within which psychological gains are facilitated, and (3) the horse itself has specific therapeutic qualities that bring about unique changes not otherwise likely to occur. The challenge for researchers in this area is to design studies that adequately test these competing hypotheses. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Adaptive hatching hypotheses do not explain asynchronous ...

    African Journals Online (AJOL)

    At the core of the suite of adaptive hatching hypotheses advanced to explain asynchronous hatching in birds is the assumption that if food is not limited then all the hatchlings will develop normally to adulthood. In this study Brown-headed Parrot Poicephalus cryptoxanthus chicks were hand fed and weighed on a daily basis.

  19. Methods for Evaluating Vocational Interest Structural Hypotheses.

    Science.gov (United States)

    Rounds, James; And Others

    1992-01-01

    Two forms of Holland's Hexagon Model (circular order and circumplex structure) are proposed and evaluated to demonstrate a randomization test of hypothesized order relations and confirmatory factor analysis. The models and methods are illustrated with correlation matrices based on the Unisex Edition of the ACT Interest Inventory. (Author/SK)

  20. Scientific'Laws','Hypotheses' and'Theories'

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 3; Issue 12. Scientific 'Laws', 'Hypotheses' and 'Theories' - How are They Related? J R Lakshmana Rao. General Article Volume 3 Issue 12 December 1998 pp 55-61. Fulltext. Click here to view fulltext PDF. Permanent link:

  1. Bayesian evaluation of inequality constrained hypotheses

    NARCIS (Netherlands)

    Gu, X.; Mulder, J.; Deković, M.; Hoijtink, H.

    2014-01-01

    Bayesian evaluation of inequality constrained hypotheses enables researchers to investigate their expectations with respect to the structure among model parameters. This article proposes an approximate Bayes procedure that can be used for the selection of the best of a set of inequality constrained

  2. Singularity hypotheses a scientific and philosophical assessment

    CERN Document Server

    Moor, James; Søraker, Johnny; Steinhart, Eric

    2012-01-01

    Singularity Hypotheses: A Scientific and Philosophical Assessment offers authoritative, jargon-free essays and critical commentaries on accelerating technological progress and the notion of technological singularity. It focuses on conjectures about the intelligence explosion, transhumanism, and whole brain emulation. Recent years have seen a plethora of forecasts about the profound, disruptive impact that is likely to result from further progress in these areas. Many commentators however doubt the scientific rigor of these forecasts, rejecting them as speculative and unfounded. We therefore invited prominent computer scientists, physicists, philosophers, biologists, economists and other thinkers to assess the singularity hypotheses. Their contributions go beyond speculation, providing deep insights into the main issues and a balanced picture of the debate.

  3. Mapping Out Biogenetic Hypotheses by Chemical Synthesis.

    Science.gov (United States)

    Liffert, Raphael; Gademann, Karl

    2017-12-01

    Synthesis of natural products via their postulated or established biosynthetic intermediates ('biomimetic synthesis' or 'bio-inspired synthesis') has the power to identify both yet undiscovered intermediates and undiscovered mechanistic pathways for their formation. In this account, we report on our recent studies on unusual hypotheses for biosynthetic transformations, such as a late-stage aldol reaction (periconianone A), benzilic acid rearrangement (taiwaniaquinone H), a redox-neutral light-driven C-H activation (taiwaniaquinol A and cyclocoulterone), a hetero Diels-Alder reaction (obtusinones), aziridinium chemistry (Securinega alkaloids), and a [3+2] nitrone olefin cycloaddition (virosaine A). All these studies provided evidence on the molecular level for the feasibility of these transformations, and suggest that further studies investigating the relevance of these hypotheses in biological systems are warranted.

  4. PREVIOUS SECOND TRIMESTER ABORTION

    African Journals Online (AJOL)

    PNLC

    PREVIOUS SECOND TRIMESTER ABORTION: A risk factor for third trimester uterine rupture in three ... for accurate diagnosis of uterine rupture. KEY WORDS: Induced second trimester abortion - Previous uterine surgery - Uterine rupture. ..... scarred uterus during second trimester misoprostol- induced labour for a missed ...

  5. New hypotheses regarding the Danish health puzzle.

    Science.gov (United States)

    Bakah, May; Raphael, Dennis

    2017-12-01

    Nordic welfare states have achieved admirable population health profiles as a result of public policies that provide economic and social security across the life course. Denmark has been an exception to this rule, as its life expectancies and infant mortality rates since the mid-1970s have lagged behind the other Nordic nations and, in the case of life expectancy, behind most Organisation for Economic Co-operation and Development nations. In this review paper, we identify a number of new hypotheses for why this may be the case. These hypotheses concern the health effects of neo-liberal restructuring of the economy and its institutions, the institution of flexi-security in Denmark's labour market and the influence of Denmark's tobacco and alcohol industries. Also of note is that Denmark experienced higher unemployment rates during its initial period of health stagnation, as well as its treatment of non-Western immigrants and high wealth inequality and, until recently, the fact that Denmark did not systematically address the issue of health inequalities. These hypotheses may serve as covering explanations for the usually provided accounts of elevated behavioural risks and psychosocial stress as being responsible for Denmark's health profile.

  6. Vicarious resilience in counselors of child and youth victims of interpersonal trauma.

    Science.gov (United States)

    Silveira, Fabiane S; Boyer, Wanda

    2015-04-01

    In this study, we investigated how bearing witness to clients' resilience processes during treatment impacts the personal and professional lives of counselors who work with child and youth victims of interpersonal trauma. We used a qualitative instrumental multiple-case study design and thematic analysis to explore the research question. The participants indicated that they experienced an increased sense of hope and optimism, and were inspired by the strengths of their clients while working with this population. As the participants reflected on the challenges that their clients faced, the participants put their own challenges and strengths into perspective; they reported positive changes in their personal relationships. We suggest that future research might investigate the relationships we found between optimism, hope, and vicarious resilience processes, as well as the potential relationship between the counseling approach that counselors adopt and the development of vicarious resilience responses. © The Author(s) 2014.

  7. Flexible goal imitation: Vicarious feedback influences stimulus-response binding by observation.

    Science.gov (United States)

    Giesen, Carina; Scherdin, Kerstin; Rothermund, Klaus

    2017-06-01

    This study investigated whether vicarious feedback influences binding processes between stimuli and observed responses. Two participants worked together in a shared color categorization task, taking the roles of actor and observer in turns. During a prime trial, participants saw a word while observing the other person executing a specific response. Automatic binding of words and observed responses into stimulus-response (S-R) episodes was assessed via word repetition effects in a subsequent probe trial in which either the same (compatible) or a different (incompatible) response had to be executed by the participants in response to the same or a different word. Results showed that vicarious prime feedback (i.e., the feedback that the other participant received for her or his response in the prime) modulated S-R retrieval effects: After positive vicarious prime feedback, typical S-R retrieval effects emerged (i.e., performance benefits for stimulus repetition probes with compatible responses, but performance costs for stimulus repetition probes with incompatible responses emerged). Notably, however, S-R-retrieval effects were reversed after vicarious negative prime feedback (meaning that stimulus repetition in the probe resulted in performance costs if prime and probe responses were compatible, and in performance benefits for incompatible responses). Findings are consistent with a flexible goal imitation account, according to which imitation is based on an interpretative and therefore feedback-sensitive reconstruction of action goals from observed movements. In concert with earlier findings, this data support the conclusion that transient S-R binding and retrieval processes are involved in social learning phenomena.

  8. INTRASPECIFIC PHYLOGEOGRAPHY OF NORTH AMERICAN HIGHLAND FISHES: A TEST OF THE PLEISTOCENE VICARIANCE HYPOTHESIS.

    Science.gov (United States)

    Strange, Rex Meade; Burr, Brooks M

    1997-06-01

    The highland fish fauna of eastern North America consists of Appalachian and Ozark centers of endemism separated by the intervening Glacial Till Plains. Clades within these areas are more closely related phylogenetically to each other than to clades occurring in the intervening formerly glaciated region, suggesting that the Pleistocene glaciations fragmented a widespread highland region and its associated fauna. Alternatively, it is possible that these faunal assemblages predate the glaciations or that recent dispersals may have been more important than vicariance in determining faunal compositions. We examined the relationships among mitochondrial DNA (mtDNA) haplotypes within five clades of highland fishes, each with a distribution suggestive of a Pleistocene vicariance event. Darters of the subgenera Litocara and Odontopholis have distributions and mtDNA relationships that are consistent with the Pleistocene integration and burial of the Teays-Mahomet valley, a major drainage of the early Pleistocene. The distribution and mtDNA relationships among subspecies of Erimystax dissimilis are not consistent with Pleistocene vicariance, but relationships among Appalachian haplotypes are consistent with the late Pleistocene integration of the modern Ohio River system. Both Cottus carolinae and the Fundulus catenatus species group have representatives in the Mobile basin consistent with pre-Pleistocene divergences. Three haplotype clusters were found in C. carolinae, corresponding to the Appalachian, Ozark, and upper Kanawha River populations. However, Appalachian and Ozark F. catenatus populations are paraphyletic with respect to each other. This, coupled with a relatively low degree of sequence divergence, suggests that no long-term barriers to gene flow exist for C. carolinae and F. catenatus. These three distinct phylogeographic patterns indicate that Pleistocene vicariance is not the only explanation for the Appalachian-Ozark distribution of highland fish communities

  9. Vicarious learning and unlearning of fear in childhood via mother and stranger models.

    Science.gov (United States)

    Dunne, Güler; Askew, Chris

    2013-10-01

    Evidence shows that anxiety runs in families. One reason may be that children are particularly susceptible to learning fear from their parents. The current study compared children's fear beliefs and avoidance preferences for animals following positive or fearful modeling by mothers and strangers in vicarious learning and unlearning procedures. Children aged 6 to 10 years (N = 60) were exposed to pictures of novel animals either alone (control) or together with pictures of their mother or a stranger expressing fear or happiness. During unlearning (counterconditioning), children saw each animal again with their mother or a stranger expressing the opposite facial expression. Following vicarious learning, children's fear beliefs increased for animals seen with scared faces and this effect was the same whether fear was modeled by mothers or strangers. Fear beliefs and avoidance preferences decreased following positive counterconditioning and increased following fear counterconditioning. Again, learning was the same whether the model was the child's mother or a stranger. These findings indicate that children in this age group can vicariously learn and unlearn fear-related cognitions from both strangers and mothers. This has implications for our understanding of fear acquisition and the development of early interventions to prevent and reverse childhood fears and phobias.

  10. Identifying, Preventing, and Addressing Job Burnout and Vicarious Burnout for Social Work Professionals.

    Science.gov (United States)

    Wilson, Felicia

    2016-01-01

    Genuineness, concern for others, and empathy are characteristics used to describe the professional social worker. To this end, the social worker tirelessly works on behalf of and in collaboration with the client to move them from stagnant life situations into positive life situations. While the fundamental principles of social work are wonderful, the result for some workers is job burnout and/or vicarious trauma. The concepts of job burnout, its antecedents, and manifestations are thoroughly discussed in this article to provide a holistic overview of this phenomenon. The six antecedents: workload, control, values, fairness, reward, and community are discussed and linked to the manifestations of job burnout. When working with individuals who have been exposed to the depravity of life, the professional can take on the client's vulnerabilities, victimizations, and stress. The common term for this phenomenon is vicarious trauma. Professionals who work with trauma victims can often have issues in their personal and professional life as evidenced by reduced professional efficacy, increased emotional concerns, and physical concerns. The purpose of the author in this article is to provide an overview of job burnout, vicarious trauma, and a discussion about self-care responsibilities.

  11. Both Direct and Vicarious Experiences of Nature Affect Children’s Willingness to Conserve Biodiversity

    Directory of Open Access Journals (Sweden)

    Masashi Soga

    2016-05-01

    Full Text Available Children are becoming less likely to have direct contact with nature. This ongoing loss of human interactions with nature, the extinction of experience, is viewed as one of the most fundamental obstacles to addressing global environmental challenges. However, the consequences for biodiversity conservation have been examined very little. Here, we conducted a questionnaire survey of elementary schoolchildren and investigated effects of the frequency of direct (participating in nature-based activities and vicarious experiences of nature (reading books or watching TV programs about nature and talking about nature with parents or friends on their affective attitudes (individuals’ emotional feelings toward and willingness to conserve biodiversity. A total of 397 children participated in the surveys in Tokyo. Children’s affective attitudes and willingness to conserve biodiversity were positively associated with the frequency of both direct and vicarious experiences of nature. Path analysis showed that effects of direct and vicarious experiences on children’s willingness to conserve biodiversity were mediated by their affective attitudes. This study demonstrates that children who frequently experience nature are likely to develop greater emotional affinity to and support for protecting biodiversity. We suggest that children should be encouraged to experience nature and be provided with various types of these experiences.

  12. Constant conditional entropy and related hypotheses

    International Nuclear Information System (INIS)

    Ferrer-i-Cancho, Ramon; Dębowski, Łukasz; Moscoso del Prado Martín, Fermín

    2013-01-01

    Constant entropy rate (conditional entropies must remain constant as the sequence length increases) and uniform information density (conditional probabilities must remain constant as the sequence length increases) are two information theoretic principles that are argued to underlie a wide range of linguistic phenomena. Here we revise the predictions of these principles in the light of Hilberg’s law on the scaling of conditional entropy in language and related laws. We show that constant entropy rate (CER) and two interpretations for uniform information density (UID), full UID and strong UID, are inconsistent with these laws. Strong UID implies CER but the reverse is not true. Full UID, a particular case of UID, leads to costly uncorrelated sequences that are totally unrealistic. We conclude that CER and its particular cases are incomplete hypotheses about the scaling of conditional entropies. (letter)

  13. Laparoscopy After Previous Laparotomy

    Directory of Open Access Journals (Sweden)

    Zulfo Godinjak

    2006-11-01

    Full Text Available Following the abdominal surgery, extensive adhesions often occur and they can cause difficulties during laparoscopic operations. However, previous laparotomy is not considered to be a contraindication for laparoscopy. The aim of this study is to present that an insertion of Veres needle in the region of umbilicus is a safe method for creating a pneumoperitoneum for laparoscopic operations after previous laparotomy. In the last three years, we have performed 144 laparoscopic operations in patients that previously underwent one or two laparotomies. Pathology of digestive system, genital organs, Cesarean Section or abdominal war injuries were the most common causes of previouslaparotomy. During those operations or during entering into abdominal cavity we have not experienced any complications, while in 7 patients we performed conversion to laparotomy following the diagnostic laparoscopy. In all patients an insertion of Veres needle and trocar insertion in the umbilical region was performed, namely a technique of closed laparoscopy. Not even in one patient adhesions in the region of umbilicus were found, and no abdominal organs were injured.

  14. Dental Hypotheses: Seeks to Publish Hypotheses from All Areas of Dentistry

    Directory of Open Access Journals (Sweden)

    Edward F. Rossomando

    2010-07-01

    Full Text Available Starting a new open access journal in a rapid growing scientific panorama is a severe challenge. However, the first issue of dental hypotheses is now history and the even skeptics can appreciate that dental hypotheses is a success - it is a journal of high quality that provides an outlet for publication of articles that encourage readers to question dental paradigms. But dental hypotheses readers might have noticed that the majority of the articles published in the first issue of dental hypotheses concern clinical dentistry. However, dental hypotheses editors recognize that there are many other areas in dentistry that present challenges and that our readers may offer suggestions for their solution. Some of these challenges relate to: dental education; digital dental technology; teledentistry and access to dental care; dental practice issues, such as, dental office design, dental office management, the slow rate of acceptance of innovative technology in the dental office; and issues related to innovation and dental entrepreneurship including intellectual property protection. Nevertheless, the dental profession faces many challenges - in many areas - and with the publication of dental hypotheses our profession has a venue for presentation of possible solutions. If you have developed a hypothesis that might help, please share it with your colleagues. As many have noted, the intellectual power of the global village in which we now live is formidable. The internet has provided the technology to bring us together and dental hypotheses has provided the venue. Please use it. New radical, speculative and non-mainstream scientific ideas are always welcome.

  15. Employers' Statutory Vicarious Liability in Terms of the Protection of Personal Information Act

    Directory of Open Access Journals (Sweden)

    Daleen Millard

    2016-07-01

    Full Text Available A person whose privacy has been infringed upon through the unlawful, culpable processing of his or her personal information can sue the infringer's employer based on vicarious liability or institute action based on the Protection of Personal Information Act 4 of 2013 (POPI. Section 99(1 of POPI provides a person (a "data subject" whose privacy has been infringed upon with the right to institute a civil action against the responsible party. POPI defines the responsible party as the person who determines the purpose of and means for the processing of the personal information of data subjects. Although POPI does not equate a responsible party to an employer, the term "responsible party" is undoubtedly a synonym for "employer" in this context. By holding an employer accountable for its employees' unlawful processing of a data subject's personal information, POPI creates a form of statutory vicarious liability. Since the defences available to an employer at common law and developed by case law differ from the statutory defences available to an employer in terms of POPI, it is necessary to compare the impact this new statute has on employers. From a risk perspective, employers must be aware of the serious implications of POPI. The question that arises is whether the Act perhaps takes matters too far. This article takes a critical look at the statutory defences available to an employer in vindication of a vicarious liability action brought by a data subject in terms of section 99(1 of POPI. It compares the defences found in section 99(2 of POPI and the common-law defences available to an employer fending off a delictual claim founded on the doctrine of vicarious liability. To support the argument that the statutory vicarious liability created by POPI is too harsh, the defences contained in section 99(2 of POPI are further analogised with those available to an employer in terms of section 60(4 of the Employment Equity Act 55 of 1998 (EEA and other

  16. Testosterone and estrogen impact social evaluations and vicarious emotions: A double-blind placebo-controlled study.

    Science.gov (United States)

    Olsson, Andreas; Kopsida, Eleni; Sorjonen, Kimmo; Savic, Ivanka

    2016-06-01

    The abilities to "read" other peoples' intentions and emotions, and to learn from their experiences, are critical to survival. Previous studies have highlighted the role of sex hormones, notably testosterone and estrogen, in these processes. Yet it is unclear how these hormones affect social cognition and emotion using acute hormonal administration. In the present double-blind placebo-controlled study, we administered an acute exogenous dose of testosterone or estrogen to healthy female and male volunteers, respectively, with the aim of investigating the effects of these steroids on social-cognitive and emotional processes. Following hormonal and placebo treatment, participants made (a) facial dominance judgments, (b) mental state inferences (Reading the Mind in the Eyes Test), and (c) learned aversive associations through watching others' emotional responses (observational fear learning [OFL]). Our results showed that testosterone administration to females enhanced ratings of facial dominance but diminished their accuracy in inferring mental states. In men, estrogen administration resulted in an increase in emotional (vicarious) reactivity when watching a distressed other during the OFL task. Taken together, these results suggest that sex hormones affect social-cognitive and emotional functions at several levels, linking our results to neuropsychiatric disorders in which these functions are impaired. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  17. Treating fossils as terminal taxa in divergence time estimation reveals ancient vicariance patterns in the palpimanoid spiders.

    Science.gov (United States)

    Wood, Hannah Marie; Matzke, Nicholas J; Gillespie, Rosemary G; Griswold, Charles E

    2013-03-01

    Incorporation of fossils into biogeographic studies can have a profound effect on the conclusions that result, particularly when fossil ranges are nonoverlapping with extant ranges. This is the case in archaeid spiders, where there are known fossils from the Northern Hemisphere, yet all living members are restricted to the Southern Hemisphere. To better understand the biogeographic patterns of archaeid spiders and their palpimanoid relatives, we estimate a dated phylogeny using a relaxed clock on a combined molecular and morphological data set. Dating information is compared with treating the archaeid fossil taxa as both node calibrations and as noncontemporaneous terminal tips, both with and without additional calibration points. Estimation of ancestral biogeographic ranges is then performed, using likelihood and Bayesian methods to take into account uncertainty in phylogeny and in dating. We find that treating the fossils as terminal tips within a Bayesian framework, as opposed to dating the phylogeny based only on molecular data with the dates coming from node calibrations, removes the subjectivity involved in assigning priors, which has not been possible with previous methods. Our analyses suggest that the diversification of the northern and southern archaeid lineages was congruent with the breakup of Pangaea into Laurasia and Gondwanaland. This analysis provides a rare example, and perhaps the most strongly supported, where a dated phylogeny confirms a biogeographical hypothesis based on vicariance due to the breakup of the ancient continental plates.

  18. A phylogenetic review of the African leaf chameleons: genus Rhampholeon (Chamaeleonidae): the role of vicariance and climate change in speciation.

    Science.gov (United States)

    Matthee, Conrad A; Tilbury, Colin R; Townsend, Ted

    2004-09-22

    The phylogenetic associations among 13 currently recognized African leaf chameleon species were investigated by making use of mitochondrial and nuclear DNA sequence data (44 taxa and 4145 characters). The gene tree indicates two divergent clades within Rhampholeon; this finding is congruent with previous morphological suggestions. The first clade (I) comprises three taxa (R. kerstenii, R. brevicaudatus and R. brachyurus) and is widely distributed in lowland forest and or non-forest biomes. The second clade (II) comprises the remaining Rhampholeon species and can be subdivided into three subclades. By contrast, most taxa belonging to clade II are confined to relict montane forest biotopes. Based on geographical, morphological and molecular evidence, it is suggested that the taxonomy of Rhampholeon be revised to include two genera (Rieppeleon and Rhampholeon) and three subgenera (Rhampholeon, Bicuspis and Rhinodigitum). There is a close correlation between geographical distribution and phylogenetic relatedness among Rhampholeon taxa, indicating that vicariance and climate change were possibly the most influential factors driving speciation in the group. A relaxed Bayesian clock suggests that speciation times coincided both with the northern movement of Africa, which caused the constriction of the pan African forest, and to rifting in east Africa ca. 20 Myr ago. Subsequent speciation among taxa was probably the result of gradual desiccation of forests between 20 and 5 Myr ago.

  19. Electroconvulsive therapy's mechanism of action: neuroendocrine hypotheses.

    Science.gov (United States)

    Haskett, Roger F

    2014-06-01

    Despite a range of etiological theories since the introduction of electroconvulsive therapy (ECT) more than 75 years ago, its mechanism of action remains poorly understood. The neuroendocrine hypothesis is based on the seizure-related release of hypothalamic hormones into the blood and cerebrospinal fluid and evidence of endocrine dysfunction in many patients with severe mood disorder. The specific effect of ECT was hypothesized to result from the transverse passage of current through the brain with direct stimulation of axial structures including the diencephalon. The prompt release of adrenocorticotropic hormone, cortisol, and prolactin into blood followed ECT with a return to pretreatment baseline levels in several hours. The elevated levels of hormones were absorbed by the cerebrospinal fluid, providing contact with brain cells and central nervous system structures. An apparently specific pattern of ECT-induced hormone changes, limited to prolactin and cortisol, suggested that ECT released a substance with dopaminergic antagonist and antipsychotic properties. As hypothalamic dysfunction is a key finding in endogenomorphic depression and the abnormal endocrine and physiological functions usually normalize with recovery, this led to a search for biological markers that would supplement clinical assessment of diagnosis and treatment response. One of these, the overnight dexamethasone suppression test found that 40% to 50% of melancholic depressed patients had abnormal results, whereas 90% of control patients suppressed normally. This was followed by a period of uncritical overenthusiasm followed by wholesale rejection of the clinical neuroendocrine strategies. Several key methodological issues received inadequate attention, and there have been calls to revisit this topic.

  20. Informative hypotheses: theory and practice for behavioral and social scientists

    National Research Council Canada - National Science Library

    Hoijtink, Herbert

    2012-01-01

    ... Hypotheses.There is currently a sound theoretical foundation for the evaluation of informative hypotheses using Bayes factors, p-values and the generalized order restricted information criterion...

  1. Electroconvulsive treatment: hypotheses about mechanisms of action

    Directory of Open Access Journals (Sweden)

    Roar eFosse

    2013-08-01

    Full Text Available No consensus has been reached on the mode of action of electroconvulsive treatment (ECT. We suggest that two features may aid in the delineation of the involved mechanisms. First, when effective, ECT would be likely to affect brain functions that are typically altered in its primary recipient group, people with severe depression. Central among these are the frontal and temporal lobes, the hypothalamus-pituitary-adrenal (HPA stress axis, and the mesocorticolimbic dopamine system. Second, the involved mechanisms should be affected for a time period that matches the average endurance of clinical effects, which is indicated to be several days to a few weeks. To identify effects upon frontal and temporal lobe functioning we reviewed human studies using EEG, PET, SPECT, and fMRI. Effects upon the HPA axis and the dopamine system were assessed by reviewing both human and animal studies. The EEG studies indicate that ECT decelerates neural activity in the frontal and temporal lobes (increased delta and theta wave activity for weeks to months. Comparable findings are reported from PET and SPECT studies, with reduced cerebral blood flow (functional deactivation for weeks to months after treatment. The EEG deceleration and functional deactivation following ECT are statistically associated with reduced depression scores. FMRI studies indicate that ECT flattens the pattern of activation and deactivation that is associated with cognitive task performance and alters cortical functional connectivity in the ultra slow frequency range. A common finding from human and animal studies is that electroconvulsive treatment acutely activates both the HPA axis and the dopamine system. In considering this evidence, we hypothesize that ECT affects the brain in a similar manner as severe stress or brain trauma which activates the HPA axis and the dopamine system and may compromise frontotemporal functions.

  2. The phylogeny and biogeographic history of ashes (fraxinus, oleaceae highlight the roles of migration and vicariance in the diversification of temperate trees.

    Directory of Open Access Journals (Sweden)

    Damien Daniel Hinsinger

    Full Text Available The cosmopolitan genus Fraxinus, which comprises about 40 species of temperate trees and shrubs occupying various habitats in the Northern Hemisphere, represents a useful model to study speciation in long-lived angiosperms. We used nuclear external transcribed spacers (nETS, phantastica gene sequences, and two chloroplast loci (trnH-psbA and rpl32-trnL in combination with previously published and newly obtained nITS sequences to produce a time-calibrated multi-locus phylogeny of the genus. We then inferred the biogeographic history and evolution of floral morphology. An early dispersal event could be inferred from North America to Asia during the Oligocene, leading to the diversification of the section Melioides sensus lato. Another intercontinental dispersal originating from the Eurasian section of Fraxinus could be dated from the Miocene and resulted in the speciation of F. nigra in North America. In addition, vicariance was inferred to account for the distribution of the other Old World species (sections Sciadanthus, Fraxinus and Ornus. Geographic speciation likely involving dispersal and vicariance could also be inferred from the phylogenetic grouping of geographically close taxa. Molecular dating suggested that the initial divergence of the taxonomical sections occurred during the middle and late Eocene and Oligocene periods, whereas diversification within sections occurred mostly during the late Oligocene and Miocene, which is consistent with the climate warming and accompanying large distributional changes observed during these periods. These various results underline the importance of dispersal and vicariance in promoting geographic speciation and diversification in Fraxinus. Similarities in life history, reproductive and demographic attributes as well as geographical distribution patterns suggest that many other temperate trees should exhibit similar speciation patterns. On the other hand, the observed parallel evolution and reversions

  3. Vicarious Radiometric Calibration of a Multispectral Camera on Board an Unmanned Aerial System

    Directory of Open Access Journals (Sweden)

    Susana Del Pozo

    2014-02-01

    Full Text Available Combinations of unmanned aerial platforms and multispectral sensors are considered low-cost tools for detailed spatial and temporal studies addressing spectral signatures, opening a broad range of applications in remote sensing. Thus, a key step in this process is knowledge of multi-spectral sensor calibration parameters in order to identify the physical variables collected by the sensor. This paper discusses the radiometric calibration process by means of a vicarious method applied to a high-spatial resolution unmanned flight using low-cost artificial and natural covers as control and check surfaces, respectively.

  4. Direct and vicarious violent victimization and juvenile delinquency: an application of general strain theory.

    Science.gov (United States)

    Lin, Wen-Hsu; Cochran, John K; Mieczkowski, Thomas

    2011-01-01

    Using a national probability sample of adolescents (12–17), this study applies general strain theory to how violent victimization, vicarious violent victimization, and dual violent victimization affect juvenile violent/property crime and drug use. In addition, the mediating effect and moderating effect of depression, low social control, and delinquent peer association on the victimization–delinquency relationship is also examined. Based on SEM analyses and contingency tables, the results indicate that all three types of violent victimization have significant and positive direct effects on violent/property crime and drug use. In addition, the expected mediating effects and moderating effects are also found. Limitations and future directions are discussed.

  5. Macaque monkeys can learn token values from human models through vicarious reward.

    Science.gov (United States)

    Bevacqua, Sara; Cerasti, Erika; Falcone, Rossella; Cervelloni, Milena; Brunamonti, Emiliano; Ferraina, Stefano; Genovesio, Aldo

    2013-01-01

    Monkeys can learn the symbolic meaning of tokens, and exchange them to get a reward. Monkeys can also learn the symbolic value of a token by observing conspecifics but it is not clear if they can learn passively by observing other actors, e.g., humans. To answer this question, we tested two monkeys in a token exchange paradigm in three experiments. Monkeys learned token values through observation of human models exchanging them. We used, after a phase of object familiarization, different sets of tokens. One token of each set was rewarded with a bit of apple. Other tokens had zero value (neutral tokens). Each token was presented only in one set. During the observation phase, monkeys watched the human model exchange tokens and watched them consume rewards (vicarious rewards). In the test phase, the monkeys were asked to exchange one of the tokens for food reward. Sets of three tokens were used in the first experiment and sets of two tokens were used in the second and third experiments. The valuable token was presented with different probabilities in the observation phase during the first and second experiments in which the monkeys exchanged the valuable token more frequently than any of the neutral tokens. The third experiments examined the effect of unequal probabilities. Our results support the view that monkeys can learn from non-conspecific actors through vicarious reward, even a symbolic task like the token-exchange task.

  6. Asymmetries in Experiential and Vicarious Feedback: Lessons from the Hiring and Firing of Baseball Managers

    Directory of Open Access Journals (Sweden)

    David Strang

    2014-05-01

    Full Text Available We examine experiential and vicarious feedback in the hiring and firing of baseball managers. Realized outcomes play a large role in both decisions; the probability that a manager will be fired is a function of the team’s win–loss record, and a manager is quicker to be rehired if his teams had won more in the past. There are substantial asymmetries, however, in the fine structure of the two feedback functions. The rate at which managers are fired is powerfully shaped by recent outcomes, falls with success and rises with failure, and adjusts for history-based expectations. By contrast, hiring reflects a longer-term perspective that emphasizes outcomes over the manager’s career as well as the most recent campaign, rewards success but does not penalize failure, and exhibits no adjustment for historical expectations. We explain these asymmetries in terms of the disparate displays of rationality that organizations enact in response to their own outcomes versus those of others. Experiential feedback is conditioned by a logic of accountability, vicarious feedback by a logic of emulation.

  7. Vicariance and dispersal form a ring distribution in nightsnakes around the Gulf of California.

    Science.gov (United States)

    Mulcahy, Daniel G; Macey, J Robert

    2009-11-01

    Plate tectonics can have profound effects on organismal distribution and is often the driving force in speciation. Through geologic processes, the Baja California Peninsula depicts two faunal patterns: one through southern vicariance with Cape separation, and the other through dispersal onto the northern peninsula, referred to as a 'dual-peninsular effect.' Here we apply a hierarchical sampling strategy that combines population-level sequence data ( approximately 800bp, nad4 region) with complete mt-genome data (aligned 15,549bp) and 5 nuclear protein encoding loci (3315bp), to test whether both patterns have occurred in one group of nightsnakes (Hypsiglena). The geologic formation of the peninsula is thought to have occurred in three stages: (1) Cape separation from mainland Mexico; (2) the northern peninsula separated, forming the northern Gulf of California; and (3) the peninsula was united through volcanic activity, while moving northward causing collision with southern California. However, the timing of events is debated. We explore phylogenetic relationships and estimate dates of divergence for nightsnakes using our hierarchical sampling strategy. Our data support both 'southern-vicariance' and 'northern-dispersal' have occurred in nightsnakes, forming a ring distribution around the Gulf of California. Two divergent forms are sympatric on the southern half of the peninsula with no indication of hybridization. Nightsnakes represent the first group to depict the 'dual-peninsular effect' with extensive overlap on the Baja California Peninsula.

  8. Signatures of vicariance, postglacial dispersal and spawning philopatry: population genetics of the walleye Sander vitreus.

    Science.gov (United States)

    Stepien, C A; Murphy, D J; Lohner, R N; Sepulveda-Villet, O J; Haponski, A E

    2009-08-01

    Population genetic relationships reveal the signatures of current processes such as reproductive behaviour and migration, as well as historic events including vicariance and climate change. We analyse population structure of native walleye Sander vitreus across North America, encompassing 10 nuclear DNA microsatellite loci, 26 spawning sites and 921 samples from watersheds across the Great Lakes, Lake Winnipeg, upper Mississippi River, Ohio River and Mobile Bay of the Gulf Coast. Geographical patterning is assessed using phylogenetic trees, pairwise F(ST) analogues, hierarchical partitioning, Mantel regression, Bayesian assignment and Monmonier geographical networks. Results reveal congruent divergences among population groups, corresponding to historic isolation in glacial refugia, dispersal patterns and basin divisions. Broad-scale relationships show genetic isolation with geographical distance, but reproductive groups within basins do not -- with some having pronounced differences. Greatest divergence distinguishes outlying Gulf Coastal and northwest populations, the latter tracing to dispersal from the Missourian refugium to former glacial Lake Agassiz, and basin isolation approximately 7000 ya. Genetic barriers in the Great Lakes separate groups in Lakes Superior, Huron's Georgian Bay, Erie and Ontario, reflecting contributions from Mississippian and Atlantic refugia, and changes in connectivity patterns. Walleye genetic patterns thus reflect vicariance among watersheds and glacial refugia, followed by re-colonization pathways and changing drainage connections that established modern-day northern populations, whose separations are maintained through spawning site fidelity. Conservation management practices should preserve genetic identity and unique characters among these divergent walleye populations.

  9. Evolution and biogeography of the slipper orchids: Eocene vicariance of the conduplicate genera in the Old and New World Tropics.

    Science.gov (United States)

    Guo, Yan-Yan; Luo, Yi-Bo; Liu, Zhong-Jian; Wang, Xiao-Quan

    2012-01-01

    Intercontinental disjunctions between tropical regions, which harbor two-thirds of the flowering plants, have drawn great interest from biologists and biogeographers. Most previous studies on these distribution patterns focused on woody plants, and paid little attention to herbs. The Orchidaceae is one of the largest families of angiosperms, with a herbaceous habit and a high species diversity in the Tropics. Here we investigate the evolutionary and biogeographical history of the slipper orchids, which represents a monophyletic subfamily (Cypripedioideae) of the orchid family and comprises five genera that are disjunctly distributed in tropical to temperate regions. A relatively well-resolved and highly supported phylogeny of slipper orchids was reconstructed based on sequence analyses of six maternally inherited chloroplast and two low-copy nuclear genes (LFY and ACO). We found that the genus Cypripedium with a wide distribution in the northern temperate and subtropical zones diverged first, followed by Selenipedium endemic to South America, and finally conduplicate-leaved genera in the Tropics. Mexipedium and Phragmipedium from the neotropics are most closely related, and form a clade sister to Paphiopedilum from tropical Asia. According to molecular clock estimates, the genus Selenipedium originated in Palaeocene, while the most recent common ancestor of conduplicate-leaved slipper orchids could be dated back to the Eocene. Ancestral area reconstruction indicates that vicariance is responsible for the disjunct distribution of conduplicate slipper orchids in palaeotropical and neotropical regions. Our study sheds some light on mechanisms underlying generic and species diversification in the orchid family and tropical disjunctions of herbaceous plant groups. In addition, we suggest that the biogeographical study should sample both regional endemics and their widespread relatives.

  10. Evolution and biogeography of the slipper orchids: Eocene vicariance of the conduplicate genera in the Old and New World Tropics.

    Directory of Open Access Journals (Sweden)

    Yan-Yan Guo

    Full Text Available Intercontinental disjunctions between tropical regions, which harbor two-thirds of the flowering plants, have drawn great interest from biologists and biogeographers. Most previous studies on these distribution patterns focused on woody plants, and paid little attention to herbs. The Orchidaceae is one of the largest families of angiosperms, with a herbaceous habit and a high species diversity in the Tropics. Here we investigate the evolutionary and biogeographical history of the slipper orchids, which represents a monophyletic subfamily (Cypripedioideae of the orchid family and comprises five genera that are disjunctly distributed in tropical to temperate regions. A relatively well-resolved and highly supported phylogeny of slipper orchids was reconstructed based on sequence analyses of six maternally inherited chloroplast and two low-copy nuclear genes (LFY and ACO. We found that the genus Cypripedium with a wide distribution in the northern temperate and subtropical zones diverged first, followed by Selenipedium endemic to South America, and finally conduplicate-leaved genera in the Tropics. Mexipedium and Phragmipedium from the neotropics are most closely related, and form a clade sister to Paphiopedilum from tropical Asia. According to molecular clock estimates, the genus Selenipedium originated in Palaeocene, while the most recent common ancestor of conduplicate-leaved slipper orchids could be dated back to the Eocene. Ancestral area reconstruction indicates that vicariance is responsible for the disjunct distribution of conduplicate slipper orchids in palaeotropical and neotropical regions. Our study sheds some light on mechanisms underlying generic and species diversification in the orchid family and tropical disjunctions of herbaceous plant groups. In addition, we suggest that the biogeographical study should sample both regional endemics and their widespread relatives.

  11. Preparation of SF5 Aromatics by Vicarious Nucleophilic Substitution Reactions of Nitro(pentafluorosulfanyl)benzenes with Carbanions

    Czech Academy of Sciences Publication Activity Database

    Beier, Petr; Pastýříková, Tereza; Iakobson, George

    2011-01-01

    Roč. 76, č. 11 (2011), s. 4781-4786 ISSN 0022-3263 Institutional research plan: CEZ:AV0Z40550506 Keywords : sulfur pentafluorides * vicarious nucleophilic aromatic substitution * nitrobenzenes Subject RIV: CC - Organic Chemistry Impact factor: 4.450, year: 2011

  12. Impact of Vicarious Learning Experiences and Goal Setting on Preservice Teachers' Self-Efficacy for Technology Integration: A Pilot Study.

    Science.gov (United States)

    Wang, Ling; Ertmer, Peggy A.

    This pilot study was designed to explore how vicarious learning experiences and goal setting influence preservice teachers' self-efficacy for integrating technology into the classroom. Twenty undergraduate students who were enrolled in an introductory educational technology course at a large midwestern university participated and were assigned…

  13. Hybrid E-Learning Tool TransLearning: Video Storytelling to Foster Vicarious Learning within Multi-Stakeholder Collaboration Networks

    Science.gov (United States)

    van der Meij, Marjoleine G.; Kupper, Frank; Beers, Pieter J.; Broerse, Jacqueline E. W.

    2016-01-01

    E-learning and storytelling approaches can support informal vicarious learning within geographically widely distributed multi-stakeholder collaboration networks. This case study evaluates hybrid e-learning and video-storytelling approach "TransLearning" by investigation into how its storytelling e-tool supported informal vicarious…

  14. A Comparison of Vicarious and Written Training Techniques Applied to Early Stimulation by Parents of Their Down Syndrome Babies.

    Science.gov (United States)

    Sanz, M. T.

    1996-01-01

    Compared effectiveness of vicarious and written training techniques to teach parents an early stimulation program for infants with Downs Syndrome. Found that infants whose parents were trained through observing a clinician stimulate their child had higher average developmental quotients in gross motor and language development between 6 and 24…

  15. Vicarious Trauma: An Exploratory Study of the Impact of Providing Sexual Abuse Treatment on Clinicians' Trust and Intimacy

    Science.gov (United States)

    VanDeusen, Karen M.; Way, Ineke

    2006-01-01

    This study examined vicarious trauma effects in male and female clinicians who treat sexual abuse survivors (n = 111) and sexual offenders (n = 272). The national survey was conducted using a random sample of clinical members of two professional organizations. Analyses tested the relationships between demographic variables, maltreatment history,…

  16. Learning from the Pros: Influence of Web-Based Expert Commentary on Vicarious Learning about Financial Markets

    Science.gov (United States)

    Ford, Matthew W.; Kent, Daniel W.; Devoto, Steven

    2007-01-01

    Web-based financial commentary, in which experts routinely express market-related thought processes, is proposed as a means for college students to learn vicariously about financial markets. Undergraduate business school students from a regional university were exposed to expert market commentary from a single financial Web site for a 6-week…

  17. Hypotheses about geoglyphs at Nasca, Peru: new discoveries

    Directory of Open Access Journals (Sweden)

    Jaroslav Klokočník

    2016-07-01

    Full Text Available The known hypotheses about the reasons why the geoglyphs in the Nasca and Palpa region of Peru were created are many: roads/paths, rituals/ceremonials, use of hallucinogens, astronomical meaning, influence of extraterrestrials, underground water… and so on. We present a new hypothesis, formulated by J. Sonnek (first published in 2011 in the context of all previous hypotheses.1 Sonnek explains the geoglyphs as tidied work areas for the production of rope and nets, although he goes much further than Stierlin. This eccentric hypothesis now has not only experimental but also archaeological and ethnographical support, which is presented here. Geoglyphs of a special shape were discovered in the pampas; they may represent technical objects – different types of ‘rope twisters’. Following this idea, Sonnek made technical devices (using today’s materials and tested them in practice; they work perfectly, see his YouTube videos.2 In November 2012, wooden pieces, which may be the remnants of ropemaking, were collected from the pampa near the towns of Nasca and Palpa, in vicinity of these hypothetic ropemaking places. Radiocarbon testing by 14C standardized radio-carbon age according to Stuiver-Polach convention and Accelerator Mass Spectroscopy (AMS of these wood pieces shows the age to be in a wide range from Early Nasca to the 17th century (and to our epoch with a fake geoglyph, too, thus supporting (but surely not proving the new hypothesis. Moreover, in the Quechua language, the word huasca, waskha (read: uasca means a rope or cord or place where these are produced. This word is very similar to ‘nasca’.

  18. Using modeling and vicarious reinforcement to produce more positive attitudes toward mental health treatment.

    Science.gov (United States)

    Buckley, Gary I; Malouff, John M

    2005-05-01

    In this study, the authors evaluated the effectiveness of a video, developed for this study and using principles of cognitive learning theory, to produce positive attitudinal change toward mental health treatment. The participants were 35 men and 45 women who were randomly assigned to watch either an experimental video, which included 3 positive 1st-person accounts of psychotherapy or a control video that focused on the psychological construct of self. Pre-intervention, post-intervention, and 2-week follow-up levels of attitude toward mental health treatment were measured using the Attitude Toward Seeking Professional Help Scale (E. H. Fischer & J. L. Turner, 1970). The experimental video group showed a significantly greater increase in positive attitude than did the control group. These results support the effectiveness of using the vicarious reinforcement elements of cognitive learning theory as a basis for changing attitudes toward mental health treatment.

  19. Vicarious trauma, secondary traumatic stress or simply burnout? Effect of trauma therapy on mental health professionals.

    Science.gov (United States)

    Devilly, Grant J; Wright, Renee; Varker, Tracey

    2009-04-01

    The aim of the present study was to perform an assessment for secondary traumatic stress (STS), vicarious trauma (VT) and workplace burnout for Australian mental health professionals involved in clinical practice. Recruited directly by mail, randomly selected participants were invited to submit a questionnaire by post or online. Of the 480 participants contacted, 152 mental health professionals completed the questionnaire, which contained measures of STS, VT and burnout. Exposure to patients' traumatic material did not affect STS, VT or burnout, contradicting the theory of the originators of STS and VT. Rather, it was found that work-related stressors best predicted therapist distress. These findings have significant implications for the direction of research and theory development in traumatic stress studies, calling into question the existence of secondary trauma-related phenomena and enterprises aimed at treating the consultants.

  20. Isozymes in Larrea divaricata and Larrea tridentata (Zygophyllaceae): a study of two amphitropical vicariants and autopolyploidy.

    Science.gov (United States)

    Cortes, M C; Hunziker, J H

    1997-10-01

    Electrophoretic variants for seven isozyme systems - probably encoded by 18 structural gene loci - in diploid populations of Larrea divaricata and diploid and tetraploid populations of its North American vicariant derivative L. tridentata were assayed by polyacrilamide and starch gel electrophoresis. High molecular similarity of diploid and tetraploid cytotypes of L. tridentata supports the hypothesis of interracial autopolyploidy. The absence of fixed heterozygosity and additive profiles indicates a low level of divergence between the parental diploids and the tetraploids. The phenogram based on the I coefficient showed the similarities between the populations of diploid L. divaricata and also between the diploid populations of L. tridentata. Both groups of diploid populations were more distantly connected to tetraploid L. tridentata.

  1. Not My Problem: Vicarious Conflict Adaptation with Human and Virtual Co-Actors

    Directory of Open Access Journals (Sweden)

    Michiel M. Spapé

    2016-04-01

    Full Text Available The Simon effect refers to an incompatibility between stimulus and response locations resulting in a conflict situation and, consequently, slower responses. Like other conflict effects, it is commonly reduced after repetitions, suggesting an executive control ability, which flexibly rewires cognitive processing and adapts to conflict. Interestingly, conflict is not necessarily individually defined: the Social Simon effect refers to a scenario where two people who share a task show a conflict effect where a single person does not. Recent studies showed these observations might converge into what could be called vicarious conflict adaptation, with evidence indicating that observing someone else’s conflict may subsequently reduce one’s own. While plausible, there is reason for doubt: both the social aspect of the Simon Effect, and the degree to which executive control accounts for the conflict adaptation effect, have become foci of debate in recent studies. Here, we present two experiments that were designed to test the social dimension of the effect by varying the social relationship between the actor and the co-actor. In Experiment 1, participants performed a conflict task with a virtual co-actor, while the actor-observer relationship was manipulated as a function of the similarity between response modalities. In Experiment 2, the same task was performed both with a virtual and with a human co-actor, while heart-rate measurements were taken to measure the impact of observed conflict on autonomous activity. While both experiments replicated the interpersonal conflict adaptation effects, neither showed evidence of the critical social dimension. We consider the findings as demonstrating that vicarious conflict adaptation does not rely on the social relationship between the actor and co-actor.

  2. Migration and fertility in Malaysia: a tale of two hypotheses.

    Science.gov (United States)

    Bach, R L

    1981-01-01

    2 hypotheses that are prevalent in the migration and fertility literature, are tested using data from the 1966-67 West Malaysian Family Survey. Particular attention is paid to conceptual and methodological frameworks of research and study of sociodemographic trends in Malaysia. Noting that confusion exists in previous studies of migration and fertility, especially in regards to comparing migrants and nonmigrants with residence background and migration experience, the 2 hypotheses are discussed: 1) the assimilation hypothesis in which a) place of childrearing (origin) is an important influence on fertility behavior (e.g. geographical differentials of fertility norms, family size preference), b) residence during childbearing period (destination) is a residential status that may be related to fertility (e.g. values, expectation, economic opportunities, contraceptive availability), and c) the assimilitation process can be expressed as a weighted combination of specific influences of either place of childrearing or childbearing; 2) the migration hypothesis in which a) there is something intrinsic to geographical shifts that cannot be accounted for by mere knowledge of the place of origin or destination, b) individuals are selected by age, education, ethnicity, and motivation, and c) the impact of migration is selected on specific fertility-related characteristics, e.g. the postponment of childbearing. The data in the study are drawn from a KAP-style national survey which utilized a stratified (size of place) probability sampling frame of 5457 married Malaysian women between 15 and 45 years of age. In view of the hypothesis, the identification of area of early socialization and adult experience measures the area of greatest influence on individual fertility behavior. Measures of migration are advantageous to approximating the true timing of migration and fertility in a causal ordering. To conclude, Bach suggests that fertility levels of migrants can be accounted for

  3. Testing hypotheses for differences between linear regression lines

    Science.gov (United States)

    Stanley J. Zarnoch

    2009-01-01

    Five hypotheses are identified for testing differences between simple linear regression lines. The distinctions between these hypotheses are based on a priori assumptions and illustrated with full and reduced models. The contrast approach is presented as an easy and complete method for testing for overall differences between the regressions and for making pairwise...

  4. A survey of etiologic hypotheses among testicular cancer researchers

    DEFF Research Database (Denmark)

    Stang, A; Trabert, B; Rusner, C

    2015-01-01

    Basic research results can provide new ideas and hypotheses to be examined in epidemiological studies. We conducted a survey among testicular cancer researchers on hypotheses concerning the etiology of this malignancy. All researchers on the mailing list of Copenhagen Testis Cancer Workshops...... the plausibility of the suggested etiologic hypotheses on a scale of 1 (very implausible) to 10 (very plausible). This report describes the methodology of the survey, the score distributions by individual hypotheses, hypothesis group, and the participants' major research fields, and discuss the hypotheses...... and corresponding authors of PubMed-indexed articles identified by the search term 'testicular cancer' and published within 10 years (in total 2750 recipients) were invited to respond to an e-mail-based survey. Participants of the 8th Copenhagen Testis Cancer Workshop in May 2014 were subsequently asked to rate...

  5. Patterns in body mass distributions: sifting among alternative hypotheses.

    Science.gov (United States)

    Allen, C R; Garmestani, A S; Havlicek, T D; Marquet, P A; Peterson, G D; Restrepo, C; Stow, C A; Weeks, B E

    2006-05-01

    Understanding how animals interact with their environment is critical for evaluating, mitigating and coping with anthropogenic alteration of Earth's biosphere. Researchers have attempted to understand some aspects of these interactions by examining patterns in animal body mass distributions. Energetic, phylogenetic, biogeographical, textural discontinuity and community interaction hypotheses have been advanced to explain observed patterns. Energetic and textural discontinuity hypotheses focus upon the allometry of resource use. The community interaction hypothesis contends that biotic interactions within assemblages of species are of primary importance. Biogeographical and phylogenetic hypotheses focus on the role of constraints on the organization of communities. This paper examines and organizes these various propositions about species body mass distributions and discusses the multiple competing hypotheses, how their predictions vary, and possible methods by which the hypotheses can be distinguished and tested. Each of the hypotheses is partial, and explains some elements of pattern in body mass distributions. The scale of appropriate application, relevance and interpretation varies among the hypotheses, and the mechanisms underlying observed patterns are likely to be multicausal and vary with scale.

  6. The King in the Partidas of Alfonso X: his Divine Vicariate and his characterization in terms of sacredness

    Directory of Open Access Journals (Sweden)

    Plácido Fernández-Viagas Escudero

    2017-07-01

    Full Text Available This paper can be considered as a cultural history analysis. Its goal is to interpret the divine vicariate of the king proclaimed in the Partidas in its legal and symbolic framework, as well to study the sacred characters attributed to the king in this code. To do this, we will use contributions from sociologists and anthropologists, which shed light on an issue that divides the historiography.

  7. Phylogeography of a widespread species: pre-glacial vicariance, refugia, occasional blocking straits and long-distance migrations.

    Science.gov (United States)

    Santiso, Xabier; Lopez, Lúa; Retuerto, Rubén; Barreiro, Rodolfo

    2016-01-13

    Phylogeographic studies give us the opportunity to reconstruct the historical migrations of species and link them with climatic and geographic variation. They are, therefore, a key tool to understanding the relationships among biology, geology and history. One of the most interesting biogeographical areas of the world is the Mediterranean region. However, in this area, the description of concordant phylogeographic patterns is quite scarce, which limits the understanding of evolutionary patterns related to climate. Species with one-dimensional distribution ranges, such as the strawberry tree (Arbutus unedo), are particularly useful to unravel these patterns. Here, we describe its phylogeographic structure and check for concordance with patterns seen in other Mediterranean plants: longitudinal/latitudinal clines of diversity, evidence for glacial refugia and the role of sea straits in dispersal. We also identify the most likely source for the disjunct Irish population. With this aim, we sequenced four chloroplast non-coding fragments of A. unedo from 23 populations covering its whole distribution. We determined the genetic diversity, population structure, haplotype genealogy and time to the most recent common ancestor. The genealogy revealed two clades that separated during the last 700 ky but before the last glacial maximum. One clade occupies Atlantic Iberia and North Africa, while the other occurs in the Western Mediterranean. The Eastern Mediterranean is inhabited by newer haplotypes derived from both clades, while the Irish population is closely related to Iberian demes. The straits of Sicily and Gibraltar partially restricted the gene flow. We concluded that a vicariance event during the Late Quaternary in the western end of the species' range followed by eastward migration seems a likely explanation for the observed phylogeographic pattern. The role of straits indicates an occasional communication between Europe and North Africa, suggesting that the latter was

  8. Endocardial tip cells in the human embryo - facts and hypotheses.

    Directory of Open Access Journals (Sweden)

    Mugurel C Rusu

    Full Text Available Experimental studies regarding coronary embryogenesis suggest that the endocardium is a source of endothelial cells for the myocardial networks. As this was not previously documented in human embryos, we aimed to study whether or not endothelial tip cells could be correlated with endocardial-dependent mechanisms of sprouting angiogenesis. Six human embryos (43-56 days were obtained and processed in accordance with ethical regulations; immunohistochemistry was performed for CD105 (endoglin, CD31, CD34, α-smooth muscle actin, desmin and vimentin antibodies. Primitive main vessels were found deriving from both the sinus venosus and aorta, and were sought to be the primordia of the venous and arterial ends of cardiac microcirculation. Subepicardial vessels were found branching into the outer ventricular myocardium, with a pattern of recruiting α-SMA+/desmin+ vascular smooth muscle cells and pericytes. Endothelial sprouts were guided by CD31+/CD34+/CD105+/vimentin+ endothelial tip cells. Within the inner myocardium, we found endothelial networks rooted from endocardium, guided by filopodia-projecting CD31+/CD34+/CD105+/ vimentin+ endocardial tip cells. The myocardial microcirculatory bed in the atria was mostly originated from endocardium, as well. Nevertheless, endocardial tip cells were also found in cardiac cushions, but they were not related to cushion endothelial networks. A general anatomical pattern of cardiac microvascular embryogenesis was thus hypothesized; the arterial and venous ends being linked, respectively, to the aorta and sinus venosus. Further elongation of the vessels may be related to the epicardium and subepicardial stroma and the intramyocardial network, depending on either endothelial and endocardial filopodia-guided tip cells in ventricles, or mostly on endocardium, in atria.

  9. Vicarious Calibration of sUAS Microbolometer Temperature Imagery for Estimation of Radiometric Land Surface Temperature

    Directory of Open Access Journals (Sweden)

    Alfonso Torres-Rua

    2017-06-01

    Full Text Available In recent years, the availability of lightweight microbolometer thermal cameras compatible with small unmanned aerial systems (sUAS has allowed their use in diverse scientific and management activities that require sub-meter pixel resolution. Nevertheless, as with sensors already used in temperature remote sensing (e.g., Landsat satellites, a radiance atmospheric correction is necessary to estimate land surface temperature. This is because atmospheric conditions at any sUAS flight elevation will have an adverse impact on the image accuracy, derived calculations, and study replicability using the microbolometer technology. This study presents a vicarious calibration methodology (sUAS-specific, time-specific, flight-specific, and sensor-specific for sUAS temperature imagery traceable back to NIST-standards and current atmospheric correction methods. For this methodology, a three-year data collection campaign with a sUAS called “AggieAir”, developed at Utah State University, was performed for vineyards near Lodi, California, for flights conducted at different times (early morning, Landsat overpass, and mid-afternoon” and seasonal conditions. From the results of this study, it was found that, despite the spectral response of microbolometer cameras (7.0 to 14.0 μm, it was possible to account for the effects of atmospheric and sUAS operational conditions, regardless of time and weather, to acquire accurate surface temperature data. In addition, it was found that the main atmospheric correction parameters (transmissivity and atmospheric radiance significantly varied over the course of a day. These parameters fluctuated the most in early morning and partially stabilized in Landsat overpass and in mid-afternoon times. In terms of accuracy, estimated atmospheric correction parameters presented adequate statistics (confidence bounds under ±0.1 for transmissivity and ±1.2 W/m2/sr/um for atmospheric radiance, with a range of RMSE below 1.0 W/m2/sr

  10. Cancer stem cell hypotheses: Impact on modern molecular ...

    Indian Academy of Sciences (India)

    CSCs) has been confirmed by a number of studies on experimental animal models. Nevertheless, it was shown that CSC hypotheses have several limitations and inconsistencies regarding the explanation of CSC origin, CSC identification and ...

  11. Site characterization and the method of multiple working hypotheses

    International Nuclear Information System (INIS)

    Fenster, D.F.; Cline, K.M.; Blair, J.A.; Stockey, J.

    1992-01-01

    Geologic investigations are necessary to determine whether a site is suitable for repository development and, if suitable, whether the site complies with regulatory requirements. Geologic processes and events often cannot be characterized without some degree of residual uncertainty. The method of multiple working hypotheses (MWH) is an approach in which alternative explanations for natural processes and/or events are identified, tested, and evaluated. This paper reports that in practice, several hypotheses may remain viable after all reasonable studies have been completed. Within the context of waste management and civil construction projects, all viable hypotheses that correspond with potential natural hazards must be analyzed in terms of adverse consequences to public health and safety, including radiological safety. For the repository licensing process, viable hypotheses remaining after the evaluation of data and quantification of uncertainty must be analyzed with regard to their consequences related to waste isolation. This approach can be used to determine whether additional studies are necessary to complete the license application

  12. Online computer-aided vicarious exposure for OCD symptoms: A pilot study.

    Science.gov (United States)

    Matthews, Allison J; Maunder, Rosie; Scanlan, Joel D; Kirkby, Kenneth C

    2017-03-01

    Computer-aided vicarious exposure (CAVE) for obsessive-compulsive disorder (OCD) is an intervention in which participants learn and rehearse exposure with response prevention (ERP) by directing a character around a virtual world. This study aimed to pilot an online CAVE program for OCD in a community sample with high OCD symptomatology. Participants (n = 78) were allocated to an intervention group (three 45-min weekly CAVE sessions) or to a waitlist control group. The treatment group were asked to complete three 45-min sessions over a four week period. Those who completed at least one CAVE session showed greater improvement on measures of OCD symptomatology at one-month post-treatment (d = 0.49-0.81) compared to waitlist (d = 0.01-0.1). Older age, past treatment and higher symptom severity were associated with non-adherence. These findings should be considered preliminary due to sample size limitations and an absence of an active control group. However, the findings suggest that further development and evaluation of the program is warranted. Preliminary findings suggest that online CAVE programs have potential to bridge treatment gaps among those reluctant to attend treatment or engage with in vivo exposure exercises. These programs may also have potential applications as an adjunct to face-to-face or online cognitive behavioural therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Spontaneous eye movements and trait empathy predict vicarious learning of fear.

    Science.gov (United States)

    Kleberg, Johan L; Selbing, Ida; Lundqvist, Daniel; Hofvander, Björn; Olsson, Andreas

    2015-12-01

    Learning to predict dangerous outcomes is important to survival. In humans, this kind of learning is often transmitted through the observation of others' emotional responses. We analyzed eye movements during an observational/vicarious fear learning procedure, in which healthy participants (N=33) watched another individual ('learning model') receiving aversive treatment (shocks) paired with a predictive conditioned stimulus (CS+), but not a control stimulus (CS-). Participants' gaze pattern towards the model differentiated as a function of whether the CS was predictive or not of a shock to the model. Consistent with our hypothesis that the face of a conspecific in distress can act as an unconditioned stimulus (US), we found that the total fixation time at a learning model's face increased when the CS+ was shown. Furthermore, we found that the total fixation time at the CS+ during learning predicted participants' conditioned responses (CRs) at a later test in the absence of the model. We also demonstrated that trait empathy was associated with stronger CRs, and that autistic traits were positively related to autonomic reactions to watching the model receiving the aversive treatment. Our results have implications for both healthy and dysfunctional socio-emotional learning. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Dissociable brain systems mediate vicarious learning of stimulus-response and action-outcome contingencies.

    Science.gov (United States)

    Liljeholm, Mimi; Molloy, Ciara J; O'Doherty, John P

    2012-07-18

    Two distinct strategies have been suggested to support action selection in humans and other animals on the basis of experiential learning: a goal-directed strategy that generates decisions based on the value and causal antecedents of action outcomes, and a habitual strategy that relies on the automatic elicitation of actions by environmental stimuli. In the present study, we investigated whether a similar dichotomy exists for actions that are acquired vicariously, through observation of other individuals rather than through direct experience, and assessed whether these strategies are mediated by distinct brain regions. We scanned participants with functional magnetic resonance imaging while they performed an observational learning task designed to encourage either goal-directed encoding of the consequences of observed actions, or a mapping of observed actions to conditional discriminative cues. Activity in different parts of the action observation network discriminated between the two conditions during observational learning and correlated with the degree of insensitivity to outcome devaluation in subsequent performance. Our findings suggest that, in striking parallel to experiential learning, neural systems mediating the observational acquisition of actions may be dissociated into distinct components: a goal-directed, outcome-sensitive component and a less flexible stimulus-response component.

  15. Vicariance and dispersal across Baja California in disjunct marine fish populations.

    Science.gov (United States)

    Bernardi, Giacomo; Findley, Lloyd; Rocha-Olivares, Axayacatl

    2003-07-01

    Population disjunctions, as a first step toward complete allopatry, present an interesting situation to study incipient speciation. The geological formation of the Baja California Peninsula currently divides 19 species of fish into disjunct populations that are found on its Pacific Coast and in the northern part of the Gulf of California (also called the Sea of Cortez), but are absent from the Cape (Cabo San Lucas) region. We studied the genetic makeup of disjunct populations for 12 of these 19 fish species. Phylogeographic patterns for the 12 species can be separated into two major classes: a first group (eight species) showed reciprocal monophyly and high genetic divergence between disjunct populations. A second group (four species) displayed what appeared to be panmictic populations. Population structure between Pacific Coast populations, across the Punta Eugenia biogeographic boundary, was also evaluated. While dispersal potential (inferred by pelagic larval duration) was a poor predictor of population structure between Gulf of California and Pacific populations, we found that population genetic subdivision along the Pacific Coast at Punta Eugenia was always positively correlated with differentiation between Pacific and Gulf of California populations. Vicariant events, ongoing gene flow, and ecological characteristics played essential roles in shaping the population structures observed in this study.

  16. Conflict between place and response navigation strategies: effects on vicarious trial and error (VTE) behaviors.

    Science.gov (United States)

    Schmidt, Brandy; Papale, Andrew; Redish, A David; Markus, Etan J

    2013-02-15

    Navigation can be accomplished through multiple decision-making strategies, using different information-processing computations. A well-studied dichotomy in these decision-making strategies compares hippocampal-dependent "place" and dorsal-lateral striatal-dependent "response" strategies. A place strategy depends on the ability to flexibly respond to environmental cues, while a response strategy depends on the ability to quickly recognize and react to situations with well-learned action-outcome relationships. When rats reach decision points, they sometimes pause and orient toward the potential routes of travel, a process termed vicarious trial and error (VTE). VTE co-occurs with neurophysiological information processing, including sweeps of representation ahead of the animal in the hippocampus and transient representations of reward in the ventral striatum and orbitofrontal cortex. To examine the relationship between VTE and the place/response strategy dichotomy, we analyzed data in which rats were cued to switch between place and response strategies on a plus maze. The configuration of the maze allowed for place and response strategies to work competitively or cooperatively. Animals showed increased VTE on trials entailing competition between navigational systems, linking VTE with deliberative decision-making. Even in a well-learned task, VTE was preferentially exhibited when a spatial selection was required, further linking VTE behavior with decision-making associated with hippocampal processing.

  17. Vicarious learning of children's social-anxiety-related fear beliefs and emotional Stroop bias.

    Science.gov (United States)

    Askew, Chris; Hagel, Anna; Morgan, Julie

    2015-08-01

    Models of social anxiety suggest that negative social experiences contribute to the development of social anxiety, and this is supported by self-report research. However, there is relatively little experimental evidence for the effects of learning experiences on social cognitions. The current study examined the effect of observing a social performance situation with a negative outcome on children's (8 to 11 years old) fear-related beliefs and cognitive processing. Two groups of children were each shown 1 of 2 animated films of a person trying to score in basketball while being observed by others; in 1 film, the outcome was negative, and in the other, it was neutral. Children's fear-related beliefs about performing in front of others were measured before and after the film and children were asked to complete an emotional Stroop task. Results showed that social fear beliefs increased for children who saw the negative social performance film. In addition, these children showed an emotional Stroop bias for social-anxiety-related words compared to children who saw the neutral film. The findings have implications for our understanding of social anxiety disorder and suggest that vicarious learning experiences in childhood may contribute to the development of social anxiety. (c) 2015 APA, all rights reserved).

  18. Drought responses of three closely related Caragana species: implication for their vicarious distribution.

    Science.gov (United States)

    Ma, Fei; Na, Xiaofan; Xu, Tingting

    2016-05-01

    Drought is a major environmental constraint affecting growth and distribution of plants in the desert region of the Inner Mongolia plateau. Caragana microphylla, C. liouana, and C. korshinskii are phylogenetically close but distribute vicariously in Mongolia plateau. To gain a better understanding of the ecological differentiation between these three species, we examined the leaf gas exchange, growth, water use efficiency, biomass accumulation and allocation by subjecting their seedlings to low and high drought treatments in a glasshouse. Increasing drought stress had a significant effect on many aspects of seedling performance in all species, but the physiology and growth varied with species in response to drought. C. korshinskii exhibited lower sensitivity of photosynthetic rate and growth, lower specific leaf area, higher biomass allocation to roots, higher levels of water use efficiency to drought compared with the other two species. Only minor interspecific differences in growth performances were observed between C. liouana and C. microphylla. These results indicated that faster seedling growth rate and more efficient water use of C. korshinskii should confer increased drought tolerance and facilitate its establishment in more severe drought regions relative to C. liouana and C. microphylla.

  19. HyQue: evaluating hypotheses using Semantic Web technologies

    Directory of Open Access Journals (Sweden)

    Callahan Alison

    2011-05-01

    Full Text Available Abstract Background Key to the success of e-Science is the ability to computationally evaluate expert-composed hypotheses for validity against experimental data. Researchers face the challenge of collecting, evaluating and integrating large amounts of diverse information to compose and evaluate a hypothesis. Confronted with rapidly accumulating data, researchers currently do not have the software tools to undertake the required information integration tasks. Results We present HyQue, a Semantic Web tool for querying scientific knowledge bases with the purpose of evaluating user submitted hypotheses. HyQue features a knowledge model to accommodate diverse hypotheses structured as events and represented using Semantic Web languages (RDF/OWL. Hypothesis validity is evaluated against experimental and literature-sourced evidence through a combination of SPARQL queries and evaluation rules. Inference over OWL ontologies (for type specifications, subclass assertions and parthood relations and retrieval of facts stored as Bio2RDF linked data provide support for a given hypothesis. We evaluate hypotheses of varying levels of detail about the genetic network controlling galactose metabolism in Saccharomyces cerevisiae to demonstrate the feasibility of deploying such semantic computing tools over a growing body of structured knowledge in Bio2RDF. Conclusions HyQue is a query-based hypothesis evaluation system that can currently evaluate hypotheses about the galactose metabolism in S. cerevisiae. Hypotheses as well as the supporting or refuting data are represented in RDF and directly linked to one another allowing scientists to browse from data to hypothesis and vice versa. HyQue hypotheses and data are available at http://semanticscience.org/projects/hyque.

  20. The revelation effect: A meta-analytic test of hypotheses.

    Science.gov (United States)

    Aßfalg, André; Bernstein, Daniel M; Hockley, William

    2017-12-01

    Judgments can depend on the activity directly preceding them. An example is the revelation effect whereby participants are more likely to claim that a stimulus is familiar after a preceding task, such as solving an anagram, than without a preceding task. We test conflicting predictions of four revelation-effect hypotheses in a meta-analysis of 26 years of revelation-effect research. The hypotheses' predictions refer to three subject areas: (1) the basis of judgments that are subject to the revelation effect (recollection vs. familiarity vs. fluency), (2) the degree of similarity between the task and test item, and (3) the difficulty of the preceding task. We use a hierarchical multivariate meta-analysis to account for dependent effect sizes and variance in experimental procedures. We test the revelation-effect hypotheses with a model selection procedure, where each model corresponds to a prediction of a revelation-effect hypothesis. We further quantify the amount of evidence for one model compared to another with Bayes factors. The results of this analysis suggest that none of the extant revelation-effect hypotheses can fully account for the data. The general vagueness of revelation-effect hypotheses and the scarcity of data were the major limiting factors in our analyses, emphasizing the need for formalized theories and further research into the puzzling revelation effect.

  1. Sapwood allocation in tropical trees: a test of hypotheses

    NARCIS (Netherlands)

    Schippers, P.; Vlam, M.; Zuidema, P.A.; Sterck, F.J.

    2015-01-01

    Carbon allocation to sapwood in tropical canopy trees is a key process determining forest carbon sequestration, and is at the heart of tree growth and dynamic global vegetation models (DGVM). Several allocation hypotheses exist including those applying assumptions on fixed allocation, pipe model,

  2. Testing Hypotheses About Glacial Cycles Against the Observational Record

    DEFF Research Database (Denmark)

    Kaufmann, Robert; Juselius, Katarina

    2013-01-01

    We estimate an identified cointegrated vector autoregression (CVAR) model of the climate system to test hypotheses about the physical mechanisms that may drive glacial cycles during the late Pleistocene. Results indicate that a permanent doubling of CO2 generates a 11.1oC rise in Antarctic temepr...

  3. On error probability exponents of many hypotheses optimal testing ...

    African Journals Online (AJOL)

    In this paper we study a model of hypotheses testing consisting of with to simple homogeneous stationary Markov chains ith finite number of states such that having different distributions from four possible transmission probabilities.For solving this problem we apply the method of type and large deviation techniques (LTD).

  4. Twelve testable hypotheses on the geobiology of weathering

    Science.gov (United States)

    S.L. Brantley; J.P. Megonigal; F.N. Scatena; Z. Balogh-Brunstad; R.T. Barnes; M.A. Bruns; P. van Cappelen; K. Dontsova; H.E. Hartnett; A.S. Hartshorn; A. Heimsath; E. Herndon; L. Jin; C.K. Keller; J.R. Leake; W.H. McDowell; F.C. Meinzer; T.J. Mozdzer; S. Petsch; J. Pett-Ridge; K.S. Pretziger; P.A. Raymond; C.S. Riebe; K. Shumaker; A. Sutton-Grier; R. Walter; K. Yoo

    2011-01-01

    Critical Zone (CZ) research investigates the chemical, physical, and biological processes that modulate the Earth's surface. Here, we advance 12 hypotheses that must be tested to improve our understanding of the CZ: (1) Solar-to-chemical conversion of energy by plants regulates flows of carbon, water, and nutrients through plant-microbe soil networks, thereby...

  5. Addressing Moderated Mediation Hypotheses: Theory, Methods, and Prescriptions

    Science.gov (United States)

    Preacher, Kristopher J.; Rucker, Derek D.; Hayes, Andrew F.

    2007-01-01

    This article provides researchers with a guide to properly construe and conduct analyses of conditional indirect effects, commonly known as moderated mediation effects. We disentangle conflicting definitions of moderated mediation and describe approaches for estimating and testing a variety of hypotheses involving conditional indirect effects. We…

  6. Bayes Factor Approaches for Testing Interval Null Hypotheses

    Science.gov (United States)

    Morey, Richard D.; Rouder, Jeffrey N.

    2011-01-01

    Psychological theories are statements of constraint. The role of hypothesis testing in psychology is to test whether specific theoretical constraints hold in data. Bayesian statistics is well suited to the task of finding supporting evidence for constraint, because it allows for comparing evidence for 2 hypotheses against each another. One issue…

  7. Landscape moderation of biodiversity patterns and processes - eight hypotheses

    NARCIS (Netherlands)

    Tscharntke, T.; Tylianakis, J.M.; Rand, T.A.; Didham, R.K.; Fahrig, L.; Batary, P.; Bengtsson, J.; Clough, Y.; Crist, T.O.; Dormann, C.; Ewers, R.M.; Frund, J.; Holt, R.D.; Holzschuh, A.; Klein, A.M.; Kleijn, D.; Kremen, C.; Landis, D.A.; Laurance, W.F.; Lindenmayer, D.B.; Scherber, C.; Sodhi, N.; Steffan-Dewenter, I.; Thies, C.; Putten, van der W.H.; Westphal, C.

    2012-01-01

    Understanding how landscape characteristics affect biodiversity patterns and ecological processes at local and landscape scales is critical for mitigating effects of global environmental change. In this review, we use knowledge gained from human-modified landscapes to suggest eight hypotheses, which

  8. Supervised Vicarious Calibration (SVC of Multi-Source Hyperspectral Remote-Sensing Data

    Directory of Open Access Journals (Sweden)

    Anna Brook

    2015-05-01

    Full Text Available Introduced in 2011, the supervised vicarious calibration (SVC approach is a promising approach to radiometric calibration and atmospheric correction of airborne hyperspectral (HRS data. This paper presents a comprehensive study by which the SVC method has been systematically examined and a complete protocol for its practical execution has been established—along with possible limitations encountered during the campaign. The technique was applied to multi-sourced HRS data in order to: (1 verify the at-sensor radiometric calibration and (2 obtain radiometric and atmospheric correction coefficients. Spanning two select study sites along the southeast coast of France, data were collected simultaneously by three airborne sensors (AisaDUAL, AHS and CASI-1500i aboard two aircrafts (CASA of National Institute for Aerospace Technology INTA ES and DORNIER 228 of NERC-ARSF Centre UK. The SVC ground calibration site was assembled along sand dunes near Montpellier and the thematic data were acquired from other areas in the south of France (Salon-de-Provence, Marseille, Avignon and Montpellier on 28 October 2010 between 12:00 and 16:00 UTC. The results of this study confirm that the SVC method enables reliable inspection and, if necessary, in-situ fine radiometric recalibration of airborne hyperspectral data. Independent of sensor or platform quality, the SVC approach allows users to improve at-sensor data to obtain more accurate physical units and subsequently improved reflectance information. Flight direction was found to be important, whereas the flight altitude posed very low impact. The numerous rules and major outcomes of this experiment enable a new standard of atmospherically corrected data based on better radiometric output. Future research should examine the potential of SVC to be applied to super-and-hyperspectral data obtained from on-orbit sensors.

  9. The endemic Patagonian vespertilionid assemblage is a depauperate ecomorphological vicariant of species-rich neotropical assemblages

    Science.gov (United States)

    Giannini, Norberto P.

    2017-01-01

    Abstract Vespertilionidae is the most diverse chiropteran family, and its diversity is concentrated in warm regions of the World; however, due to physiological and behavioral adaptations, these bats also dominate bat faunas in temperate regions. Here we performed a comparative study of vespertilionid assemblages from two broad regions of the New World, the cold and harsh Patagonia, versus the remaining temperate-to-subtropical, extra-Patagonian eco-regions of the South American Southern Cone. We took an ecomorphological approach and analyzed the craniodental morphological structure of these assemblages within a phylogenetic framework. We measured 17 craniodental linear variables from 447 specimens of 22 currently recognized vespertilionid species of the study regions. We performed a multivariate analysis to define the morphofunctional space, and calculated the pattern and degree of species packing for each assemblage. We assessed the importance of phylogeny and biogeography, and their impact on depauperate (Patagonian) versus rich (extra-Patagonian) vespertilionid assemblages as determinants of morphospace structuring. We implemented a sensitivity analysis associated to small samples of rare species. The morphological patterns were determined chiefly by the evolutionary history of the family. The Patagonian assemblage can be described as a structurally similar but comparatively depauperate ecomorphological version of those assemblages from neighboring extra-Patagonian eco-regions. The Patagonian assemblage seems to have formed by successively adding populations from Northern regions that eventually speciated in the region, leaving corresponding sisters (vicariants) in extra-Patagonian eco-regions that continued to be characteristically richer. Despite being structurally akin, degree of species packing in Patagonia was comparatively very low, which may reflect the effect of limited dispersal success into a harsh region for bat survival. PMID:29492009

  10. Causes of bat fatalities at wind turbines: Hypotheses and predictions

    Science.gov (United States)

    Cryan, P.M.; Barclay, R.M.R.

    2009-01-01

    Thousands of industrial-scale wind turbines are being built across the world each year to meet the growing demand for sustainable energy. Bats of certain species are dying at wind turbines in unprecedented numbers. Species of bats consistently affected by turbines tend to be those that rely on trees as roosts and most migrate long distances. Although considerable progress has been made in recent years toward better understanding the problem, the causes of bat fatalities at turbines remain unclear. In this synthesis, we review hypothesized causes of bat fatalities at turbines. Hypotheses of cause fall into 2 general categoriesproximate and ultimate. Proximate causes explain the direct means by which bats die at turbines and include collision with towers and rotating blades, and barotrauma. Ultimate causes explain why bats come close to turbines and include 3 general types: random collisions, coincidental collisions, and collisions that result from attraction of bats to turbines. The random collision hypothesis posits that interactions between bats and turbines are random events and that fatalities are representative of the bats present at a site. Coincidental hypotheses posit that certain aspects of bat distribution or behavior put them at risk of collision and include aggregation during migration and seasonal increases in flight activity associated with feeding or mating. A surprising number of attraction hypotheses suggest that bats might be attracted to turbines out of curiosity, misperception, or as potential feeding, roosting, flocking, and mating opportunities. Identifying, prioritizing, and testing hypothesized causes of bat collisions with wind turbines are vital steps toward developing practical solutions to the problem. ?? 2009 American Society of Mammalogists.

  11. Interpreters’ Experiences of Transferential Dynamics, Vicarious Traumatisation, and Their Need for Support and Supervision: A Systematic Literature Review

    Directory of Open Access Journals (Sweden)

    Emma Darroch

    2016-08-01

    Full Text Available Using thematic analysis, this systematic review aimed to explore sign language interpreters’ experiences of transferential dynamics and vicarious trauma. The notion of transferential dynamics, such as transference and countertransference, originate from psychodynamic therapy and refer to the mutual impact that client and therapist have on one another (Chessick, 1986. Psychodynamic models of therapy are predominantly concerned with unconscious processes and theorise that such processes have a powerful influence over an individuals’ thoughts, feelings and behaviours (Howard, 2011. In contrast to countertransference, which is a immediate response to a particular client, vicarious trauma is thought to develop as a result of continuous exposure to, and engagement across, many therapeutic interactions (Pearlman & Saakvitne, 1995a. A search of the available literature uncovered a striking lack of literature into the experiences of sign language interpreters, and in all, only two of the 11 identified empirical studies addressed sign language interpreters. The vast majority of the literature analysed reflected the experiences of spoken language interpreters. The results indicate that interpreters experience transferential dynamics as part of their work as well as suggesting the presence of vicarious trauma among interpreters. Additionally, a unique contribution to the fields of interpreting and psychology is offered, as it is consistently demonstrated that ‘service providers’ and ‘mental health workers’, which are umbrella terms for psychologists, immensely under-estimate the role of interpreters, as they fail to consider the emotional impact of their work and ignore the linguistic complexities of translation by failing to appreciate their need for information in order to ensure an effective translation.

  12. Vicarious calibration of the solar reflection channels of radiometers onboard satellites through the field campaigns with measurements of refractive index and size distribution of aerosols

    Science.gov (United States)

    Arai, K.

    A comparative study on vicarious calibration for the solar reflection channels of radiometers onboard satellite through the field campaigns between with and without measurements of refractive index and size distribution of aerosols is made. In particular, it is noticed that the influence due to soot from the cars exhaust has to be care about for the test sites near by a heavy trafficked roads. It is found that the 0.1% inclusion of soot induces around 10% vicarious calibration error so that it is better to measure refractive index properly at the test site. It is found that the vicarious calibration coefficients with the field campaigns at the different test site, Ivanpah (near road) and Railroad (distant from road) shows approximately 10% discrepancy. It seems that one of the possible causes for the difference is the influence due to soot from cars exhaust.

  13. Vicariously touching products through observing others' hand actions increases purchasing intention, and the effect of visual perspective in this process: An fMRI study.

    Science.gov (United States)

    Liu, Yi; Zang, Xuelian; Chen, Lihan; Assumpção, Leonardo; Li, Hong

    2018-01-01

    The growth of online shopping increases consumers' dependence on vicarious sensory experiences, such as observing others touching products in commercials. However, empirical evidence on whether observing others' sensory experiences increases purchasing intention is still scarce. In the present study, participants observed others interacting with products in the first- or third-person perspective in video clips, and their neural responses were measured with functional magnetic resonance imaging (fMRI). We investigated (1) whether and how vicariously touching certain products affected purchasing intention, and the neural correlates of this process; and (2) how visual perspective interacts with vicarious tactility. Vicarious tactile experiences were manipulated by hand actions touching or not touching the products, while the visual perspective was manipulated by showing the hand actions either in first- or third-person perspective. During the fMRI scanning, participants watched the video clips and rated their purchasing intention for each product. The results showed that, observing others touching (vs. not touching) the products increased purchasing intention, with vicarious neural responses found in mirror neuron systems (MNS) and lateral occipital complex (LOC). Moreover, the stronger neural activities in MNS was associated with higher purchasing intention. The effects of visual perspectives were found in left superior parietal lobule (SPL), while the interaction of tactility and visual perspective was shown in precuneus and precuneus-LOC connectivity. The present study provides the first evidence that vicariously touching a given product increased purchasing intention and the neural activities in bilateral MNS, LOC, left SPL and precuneus are involved in this process. Hum Brain Mapp 39:332-343, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  14. Dissolution of hypotheses in biochemistry: three case studies.

    Science.gov (United States)

    Fry, Michael

    2016-12-01

    The history of biochemistry and molecular biology is replete with examples of erroneous theories that persisted for considerable lengths of time before they were rejected. This paper examines patterns of dissolution of three such erroneous hypotheses: The idea that nucleic acids are tetrads of the four nucleobases ('the tetranucleotide hypothesis'); the notion that proteins are collinear with their encoding genes in all branches of life; and the hypothesis that proteins are synthesized by reverse action of proteolytic enzymes. Analysis of these cases indicates that amassed contradictory empirical findings did not prompt critical experimental testing of the prevailing theories nor did they elicit alternative hypotheses. Rather, the incorrect models collapsed when experiments that were not purposely designed to test their validity exposed new facts.

  15. Furious Frederich: Nietzsche's neurosyphilis diagnosis and new hypotheses.

    Science.gov (United States)

    André, Charles; Rios, André Rangel

    2015-12-01

    The causes of Friedrich Nietzsche's mental breakdown in early 1889 and of the subsequent slow decay to end-stage dementia along ten years will possibly remain open to debate. The diagnosis of syphilitic dementia paralytica, based only on medical anamnesis and physical examination, was considered indisputable by Otto Binswanger. On the other hand, taking into account recently described diseases, selectively collected evidence lend some support to alternative hypotheses: basal forebrain meningioma, CADASIL, MELAS and frontotemporal dementia.

  16. Vaccines and Autism: A Tale of Shifting Hypotheses

    OpenAIRE

    Gerber, Jeffrey S.; Offit, Paul A.

    2009-01-01

    Although child vaccination rates remain high, some parental concern persists that vaccines might cause autism. Three specific hypotheses have been proposed: (1) the combination measles-mumps-rubella vaccine causes autism by damaging the intestinal lining, which allows the entrance of encephalopathic proteins; (2) thimerosal, an ethylmercury-containing preservative in some vaccines, is toxic to the central nervous system; and (3) the simultaneous administration of multiple vaccines overwhelms ...

  17. Evaluation of seven hypotheses for metamemory performance in rhesus monkeys

    Science.gov (United States)

    Basile, Benjamin M.; Schroeder, Gabriel R.; Brown, Emily Kathryn; Templer, Victoria L.; Hampton, Robert R.

    2014-01-01

    Knowing the extent to which nonhumans and humans share mechanisms for metacognition will advance our understanding of cognitive evolution and will improve selection of model systems for biomedical research. Some nonhuman species avoid difficult cognitive tests, seek information when ignorant, or otherwise behave in ways consistent with metacognition. There is agreement that some nonhuman animals “succeed” in these metacognitive tasks, but little consensus about the cognitive mechanisms underlying performance. In one paradigm, rhesus monkeys visually searched for hidden food when ignorant of the location of the food, but acted immediately when knowledgeable. This result has been interpreted as evidence that monkeys introspectively monitored their memory to adaptively control information seeking. However, convincing alternative hypotheses have been advanced that might also account for the adaptive pattern of visual searching. We evaluated seven hypotheses using a computerized task in which monkeys chose either to take memory tests immediately or to see the answer again before proceeding to the test. We found no evidence to support the hypotheses of behavioral cue association, rote response learning, expectancy violation, response competition, generalized search strategy, or postural mediation. In contrast, we repeatedly found evidence to support the memory monitoring hypothesis. Monkeys chose to see the answer when memory was poor, either from natural variation or experimental manipulation. We found limited evidence that monkeys also monitored the fluency of memory access. Overall, the evidence indicates that rhesus monkeys can use memory strength as a discriminative cue for information seeking, consistent with introspective monitoring of explicit memory. PMID:25365530

  18. ADOPTING SOCIO-DEMOGRAPHIC CHARACTERISTICS IN PROFILING GREEN CONSUMERS: A REVIEW OF HYPOTHESES

    Directory of Open Access Journals (Sweden)

    Arif Hartono

    2009-02-01

    Full Text Available In the last three decades worldwide environmental consciousness has increased dramatically as well as profiling green consumers have gained tremendous attention in the past. Segmenting and targeting markets base on pro-environmental purchase behavior are essential when companies positioning their green products. Socio-demographic characteristics have gained a lot of attention as the key profiling variables. Such characteristics have been employed by many scholars more frequently for the bases of segmenting and profiling green consumers. However, most existing studies of green consumers’ socio-demographic were US based. The present article attempts to review the common hypotheses of socio-demographic characteristics in profiling green consumers. The present article reviews five general hypotheses relating to socio-demographics and environmental consciousness of green consumers, namely the gender, age, education level, income, and occupation hypotheses, as well as the theoretical explanation for each hypothesis. Most previous studies tend to have the same conclusion in the gender, age, education level, and  income characteristics. Critics to socio-demographic characteristics and a need to conduct green marketing research in Indonesia was also reviewed.Key words: profiling, socio-demographic, green consumer, hypotheses.

  19. Effects of MK-801 on vicarious trial-and-error and reversal of olfactory discrimination learning in weanling rats.

    Science.gov (United States)

    Griesbach, G S; Hu, D; Amsel, A

    1998-12-01

    The effects of dizocilpine maleate (MK-801) on vicarious trial-and-error (VTE), and on simultaneous olfactory discrimination learning and its reversal, were observed in weanling rats. The term VTE was used by Tolman (The determiners of behavior at a choice point. Psychol. Rev. 1938;46:318-336), who described it as conflict-like behavior at a choice-point in simultaneous discrimination learning. It takes the form of head movements from one stimulus to the other, and has recently been proposed by Amsel (Hippocampal function in the rat: cognitive mapping or vicarious trial-and-error? Hippocampus, 1993;3:251-256) as related to hippocampal, nonspatial function during this learning. Weanling male rats received systemic MK-801 either 30 min before the onset of olfactory discrimination training and its reversal, or only before its reversal. The MK-801-treated animals needed significantly more sessions to acquire the discrimination and showed significantly fewer VTEs in the acquisition phase of learning. Impaired reversal learning was shown only when MK-801 was administered during the reversal-learning phase, itself, and not when it was administered throughout both phases.

  20. Noradrenergic signaling in the medial prefrontal cortex and amygdala differentially regulates vicarious trial-and-error in a spatial decision-making task.

    Science.gov (United States)

    Amemiya, Seiichiro; Kubota, Natsuko; Umeyama, Nao; Nishijima, Takeshi; Kita, Ichiro

    2016-01-15

    In uncertain choice situations, we deliberately search and evaluate possible options before taking an action. Once we form a preference regarding the current situation, we take an action more automatically and with less deliberation. In rats, the deliberation process can be seen in vicarious trial-and-error behavior (VTE), which is a head-orienting behavior toward options at a choice point. Recent neurophysiological findings suggest that VTE reflects the rat's thinking about future options as deliberation, expectation, and planning when rats feel conflict. VTE occurs depending on the demand: an increase occurs during initial learning, and a decrease occurs with progression in learning. However, the brain circuit underlying the regulation of VTE has not been thoroughly examined. In situations in which VTE often appears, the medial prefrontal cortex (mPFC) and the amygdala (AMY) are crucial for learning and decision making. Our previous study reported that noradrenaline regulates VTE. Here, to investigate whether the mPFC and AMY are involved in regulation of VTE, we examined the effects of local injection of clonidine, an alpha2 adrenergic autoreceptor agonist, into either region in rats during VTE and choice behavior during a T-maze choice task. Injection of clonidine into either region impaired selection of the advantageous choice in the task. Furthermore, clonidine injection into the mPFC suppressed occurrence of VTE in the early phase of the task, whereas injection into the AMY inhibited the decrease in VTE in the later phase and thus maintained a high level of VTE throughout the task. These results suggest that the mPFC and AMY play a role in the increase and decrease in VTE, respectively, and that noradrenergic mechanisms mediate the dynamic regulation of VTE over experiences. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Hypothesized eye movements of neurolinguistic programming: a statistical artifact.

    Science.gov (United States)

    Farmer, A; Rooney, R; Cunningham, J R

    1985-12-01

    Neurolinguistic programming's hypothesized eye-movements were measured independently from videotapes of 30 subjects, aged 15 to 76 yr., who were asked to recall visual pictures, recorded audio sounds, and textural objects. chi 2 indicated that subjects' responses were significantly different from those predicted. When chi 2 comparisons were weighted by number of eye positions assigned to each modality (3 visual, 3 auditory, 1 kinesthetic), subjects' responses did not differ significantly from the expected pattern. These data indicate that the eye-movement hypothesis may represent randomly occurring rather than sensory-modality-related positions.

  2. Fuzzy Hypotheses Testing in the Framework of Fuzzy Logic

    Czech Academy of Sciences Publication Activity Database

    Holeňa, Martin

    2004-01-01

    Roč. 145, - (2004), s. 229-252 ISSN 0165-0114 R&D Projects: GA AV ČR IAA1030004; GA MŠk OC 274.001 Grant - others:COST(XE) Action 274 TARSKI Institutional research plan: CEZ:AV0Z1030915 Keywords : non-classical logics * fuzzy predicate calculus * basic fuzzy logic * generalized quantifiers * fuzzy statistics and data analysis * vague hypotheses * vague significance level * method Guha Subject RIV: BB - Applied Statistics , Operational Research Impact factor: 0.734, year: 2004

  3. Vaccines and autism: a tale of shifting hypotheses.

    Science.gov (United States)

    Gerber, Jeffrey S; Offit, Paul A

    2009-02-15

    Although child vaccination rates remain high, some parental concern persists that vaccines might cause autism. Three specific hypotheses have been proposed: (1) the combination measles-mumps-rubella vaccine causes autism by damaging the intestinal lining, which allows the entrance of encephalopathic proteins; (2) thimerosal, an ethylmercury-containing preservative in some vaccines, is toxic to the central nervous system; and (3) the simultaneous administration of multiple vaccines overwhelms or weakens the immune system. We will discuss the genesis of each of these theories and review the relevant epidemiological evidence.

  4. On Consistent Nonparametric Statistical Tests of Symmetry Hypotheses

    Directory of Open Access Journals (Sweden)

    Jean-François Quessy

    2016-05-01

    Full Text Available Being able to formally test for symmetry hypotheses is an important topic in many fields, including environmental and physical sciences. In this paper, one concentrates on a large family of nonparametric tests of symmetry based on Cramér–von Mises statistics computed from empirical distribution and characteristic functions. These tests possess the highly desirable property of being universally consistent in the sense that they detect any kind of departure from symmetry as the sample size becomes large. The asymptotic behaviour of these test statistics under symmetry is deduced from the theory of first-order degenerate V-statistics. The issue of computing valid p-values is tackled using the multiplier bootstrap method suitably adapted to V-statistics, yielding elegant, easy-to-compute and quick procedures for testing symmetry. A special focus is put on tests of univariate symmetry, bivariate exchangeability and reflected symmetry; a simulation study indicates the good sampling properties of these tests. Finally, a framework for testing general symmetry hypotheses is introduced.

  5. Seed dormancy and germination—emerging mechanisms and new hypotheses

    Science.gov (United States)

    Nonogaki, Hiroyuki

    2014-01-01

    Seed dormancy has played a significant role in adaptation and evolution of seed plants. While its biological significance is clear, molecular mechanisms underlying seed dormancy induction, maintenance and alleviation still remain elusive. Intensive efforts have been made to investigate gibberellin and abscisic acid metabolism in seeds, which greatly contributed to the current understanding of seed dormancy mechanisms. Other mechanisms, which might be independent of hormones, or specific to the seed dormancy pathway, are also emerging from genetic analysis of “seed dormancy mutants.” These studies suggest that chromatin remodeling through histone ubiquitination, methylation and acetylation, which could lead to transcription elongation or gene silencing, may play a significant role in seed dormancy regulation. Small interfering RNA and/or long non-coding RNA might be a trigger of epigenetic changes at the seed dormancy or germination loci, such as DELAY OF GERMINATION1. While new mechanisms are emerging from genetic studies of seed dormancy, novel hypotheses are also generated from seed germination studies with high throughput gene expression analysis. Recent studies on tissue-specific gene expression in tomato and Arabidopsis seeds, which suggested possible “mechanosensing” in the regulatory mechanisms, advanced our understanding of embryo-endosperm interaction and have potential to re-draw the traditional hypotheses or integrate them into a comprehensive scheme. The progress in basic seed science will enable knowledge translation, another frontier of research to be expanded for food and fuel production. PMID:24904627

  6. Evolution of rattlesnakes (Viperidae; Crotalus) in the warm deserts of western North America shaped by Neogene vicariance and Quaternary climate change.

    Science.gov (United States)

    Douglas, Michael E; Douglas, Marlis R; Schuett, Gordon W; Porras, Louis W

    2006-10-01

    During Pleistocene, the Laurentide ice sheet rearranged and diversified biotic distributions in eastern North America, yet had minimal physical impact in western North America where lineage diversification is instead hypothesized to result from climatic changes. If Pleistocene climatic fluctuations impacted desert species, the latter would reflect patterns of restricted gene flow concomitant with indications of demographic bottlenecks. Accordingly, molecular evidence for refugia should be present within these distributions and for subsequent range expansions as conditions improved. We sought answers to these questions by evaluating mitochondrial DNA (mtDNA) sequences from four species of rattlesnakes [Crotalus mitchellii (speckled rattlesnake), Crotalus cerastes (sidewinder), Crotalus tigris (tiger rattlesnake), Crotalus ruber (red diamond rattlesnake)] with distributions restricted to desert regions of southwestern North America. We inferred relationships using parsimony and maximum likelihood, tested intraspecific clades for population expansions, applied an isolation-with-migration model to determine bi-directional migration rates (m) among regions, and inferred divergence times for species and clades by applying a semiparametric penalized likelihood approach to our molecular data. Evidence for significant range expansion was present in two of eight regions in two species (Crotalus mitchellii pyrrhus, C. tigris region north). Two species (C. cerastes, C. mitchellii) showed a distribution concomitant with northward displacement of Baja California from mainland México, followed by vicariant separation into subclades. Effects of Pleistocene climate fluctuations were found in the distributions of all four species. Three regional diversification patterns were identified: (i) shallow genetic diversity that resulted from Pleistocene climatic events (C. tigris, C. ruber); (ii) deep Pleistocene divisions indicating allopatric segregation of subclades within refugia (C

  7. Influence of previous knowledge in Torrance tests of creative thinking

    OpenAIRE

    Aranguren, María; Consejo Nacional de Investigaciones Científicas y Técnicas CONICET

    2015-01-01

    The aim of this work is to analyze the influence of study field, expertise and recreational activities participation in Torrance Tests of Creative Thinking (TTCT, 1974) performance. Several hypotheses were postulated to explore the possible effects of previous knowledge in TTCT verbal and TTCT figural university students’ outcomes. Participants in this study included 418 students from five study fields: Psychology;Philosophy and Literature, Music; Engineering; and Journalism and Advertisin...

  8. Just watching the game ain’t enough: Striatal fMRI reward responses to successes and failures in a video game during active and vicarious playing

    Directory of Open Access Journals (Sweden)

    Jari eKätsyri

    2013-06-01

    Full Text Available Although the multimodal stimulation provided by modern audiovisual video games is pleasing by itself, the rewarding nature of video game playing depends critically also on the players’ active engagement in the gameplay. The extent to which active engagement influences dopaminergic brain reward circuit responses remains unsettled. Here we show that striatal reward circuit responses elicited by successes (wins and failures (losses in a video game are stronger during active than vicarious gameplay. Eleven healthy males both played a competitive first-person tank shooter game (active playing and watched a pre-recorded gameplay video (vicarious playing while their hemodynamic brain activation was measured with 3-tesla functional magnetic resonance imaging (fMRI. Wins and losses were paired with symmetrical monetary rewards and punishments during active and vicarious playing so that the external reward context remained identical during both conditions. Brain activation was stronger in the orbitomedial prefrontal cortex (omPFC during winning than losing, both during active and vicarious playing conditions. In contrast, both wins and losses suppressed activations in the midbrain and striatum during active playing; however, the striatal suppression, particularly in the anterior putamen, was more pronounced during loss than win events. Sensorimotor confounds related to joystick movements did not account for the results. Self-ratings indicated losing to be more unpleasant during active than vicarious playing. Our findings demonstrate striatum to be selectively sensitive to self-acquired rewards, in contrast to frontal components of the reward circuit that process both self-acquired and passively received rewards. We propose that the striatal responses to repeated acquisition of rewards that are contingent on game related successes contribute to the motivational pull of video-game playing.

  9. Just watching the game ain't enough: striatal fMRI reward responses to successes and failures in a video game during active and vicarious playing.

    Science.gov (United States)

    Kätsyri, Jari; Hari, Riitta; Ravaja, Niklas; Nummenmaa, Lauri

    2013-01-01

    Although the multimodal stimulation provided by modern audiovisual video games is pleasing by itself, the rewarding nature of video game playing depends critically also on the players' active engagement in the gameplay. The extent to which active engagement influences dopaminergic brain reward circuit responses remains unsettled. Here we show that striatal reward circuit responses elicited by successes (wins) and failures (losses) in a video game are stronger during active than vicarious gameplay. Eleven healthy males both played a competitive first-person tank shooter game (active playing) and watched a pre-recorded gameplay video (vicarious playing) while their hemodynamic brain activation was measured with 3-tesla functional magnetic resonance imaging (fMRI). Wins and losses were paired with symmetrical monetary rewards and punishments during active and vicarious playing so that the external reward context remained identical during both conditions. Brain activation was stronger in the orbitomedial prefrontal cortex (omPFC) during winning than losing, both during active and vicarious playing. In contrast, both wins and losses suppressed activations in the midbrain and striatum during active playing; however, the striatal suppression, particularly in the anterior putamen, was more pronounced during loss than win events. Sensorimotor confounds related to joystick movements did not account for the results. Self-ratings indicated losing to be more unpleasant during active than vicarious playing. Our findings demonstrate striatum to be selectively sensitive to self-acquired rewards, in contrast to frontal components of the reward circuit that process both self-acquired and passively received rewards. We propose that the striatal responses to repeated acquisition of rewards that are contingent on game related successes contribute to the motivational pull of video-game playing.

  10. Psychohistorical Hypotheses on Japan's History of Hostility Towards China.

    Science.gov (United States)

    Wang, Bo; Rudmin, Floyd

    2016-01-01

    The accelerating tensions and military posturing between Japan and China have created a serious crisis with a danger of a catastrophic war. The purpose of this paper is to summarize the events of the current crisis, and to put it in the context of Japan's long history of hostility to China and repeated attempts at conquest. The historical record shows that Japan has attacked China at least seven times, even though China has never attacked Japan. The irrationality of Japan's behavior is demonstrated by the repetition of this hostile behavior despite the enormous human and economic costs that Japan has suffered because of it. The irrationality of Japan's militarism suggests that psychological explanations may be required to understand this phenomenon. Several hypotheses are proposed, including 1) projected paranoid aggression, 2) collective Zeigarnik compulsion, 3) perceived weakness exciting aggression, 4) national inferiority feelings, 5) cultural narcissism, and 6) Oedipal-like hatred of a parent culture.

  11. Political Participation Online: The Replacement and the Mobilisation Hypotheses Revisited

    DEFF Research Database (Denmark)

    Jensen, Jakob Linaa

    2013-01-01

    of the Internet. The pure replacement hypothesis is rejected. Instead, it is found that the Internet still supplements rather than replaces other media, even among heavy Internet users. The Internet is one among several media used by ‘media omnivores’, and political participation online supplements rather than...... participation, efficacy and social capital seem to have less impact on online political participation. In the end, these findings are related to more overall discussions on the democratising potential of the Internet.......This article discusses the state of political participation online more than ten years after the Internet’s great popular breakthrough as an everyday medium. Denmark is used as a case study to critically re-examine the frequently discussed replacement and mobilisation hypotheses on behalf...

  12. Two hypotheses on the causes of male homosexuality and paedophilia.

    Science.gov (United States)

    James, William H

    2006-11-01

    This note considers two hypotheses on the causes of homosexuality and paedophilia in men, viz. the hypotheses of maternal immunity and of postnatal learning. According to the maternal immune hypothesis, there is progressive immunization of some mothers to male-specific antigens by each succeeding male fetus, and there are concomitantly increasing effects of anti-male antibodies on the sexual differentiation of the brain in each succeeding male fetus. An attempt is made to assess the status of this hypothesis within immunology. Knowledge of the properties of anti-male antibodies is meagre and there has been little direct experimentation on them, let alone on their effects on the developing male fetal brain. Moreover until the relevant antigens are identified, it will not be possible to test mothers of male homosexuals or paedophiles for the presence of such antibodies. Yet until this experimentation has been done, it would seem premature to regard the hypothesis as more than a very provisional explanatory tool. The evidence in relation to the postnatal learning hypothesis is quite different. There is an abundance of data suggesting that male homosexuals and paedophiles report having experienced more sexual abuse (however defined) in childhood (CSA) than do heterosexual controls. The question revolves round the interpretation of these data. Many (though not all) of these studies are correlational and thus subject to the usual qualifications concerning such data. However, there are grounds for supposing that some of the reports are veridical, and there is support from a longitudinal study reporting a small but significant increase in paedophilia in adulthood following CSA. To summarize: most boys who experience CSA do not later develop into homosexuals or paedophiles. However, the available evidence suggests that a few do so as a result of the abuse.

  13. Testing evolutionary hypotheses for phenotypic divergence using landscape genetics.

    Science.gov (United States)

    Funk, W Chris; Murphy, Melanie A

    2010-02-01

    Understanding the evolutionary causes of phenotypic variation among populations has long been a central theme in evolutionary biology. Several factors can influence phenotypic divergence, including geographic isolation, genetic drift, divergent natural or sexual selection, and phenotypic plasticity. But the relative importance of these factors in generating phenotypic divergence in nature is still a tantalizing and unresolved problem in evolutionary biology. The origin and maintenance of phenotypic divergence is also at the root of many ongoing debates in evolutionary biology, such as the extent to which gene flow constrains adaptive divergence (Garant et al. 2007) and the relative importance of genetic drift, natural selection, and sexual selection in initiating reproductive isolation and speciation (Coyne & Orr 2004). In this issue, Wang & Summers (2010) test the causes of one of the most fantastic examples of phenotypic divergence in nature: colour pattern divergence among populations of the strawberry poison frog (Dendrobates pumilio) in Panama and Costa Rica (Fig. 1). This study provides a beautiful example of the use of the emerging field of landscape genetics to differentiate among hypotheses for phenotypic divergence. Using landscape genetic analyses, Wang & Summers were able to reject the hypotheses that colour pattern divergence is due to isolation-by-distance (IBD) or landscape resistance. Instead, the hypothesis left standing is that colour divergence is due to divergent selection, in turn driving reproductive isolation among populations with different colour morphs. More generally, this study provides a wonderful example of how the emerging field of landscape genetics, which has primarily been applied to questions in conservation and ecology, now plays an essential role in evolutionary research.

  14. About hypotheses and paradigms: exploring the Discreetness-Chance Paradigm.

    Science.gov (United States)

    Kaellis, Eugene

    2006-01-01

    Hypotheses generally conform to paradigms which, over time, change, usually tardily, after they have become increasingly difficult to sustain under the impact of non-conforming evidence and alternative hypotheses, but more important, when they no longer are comfortably ensconced in the surrounding social-economic-political-cultural milieu. It is asserted that this milieu is the most important factor in shaping scientific theorizing. Some examples are cited: the rejection of the evidence that the world orbits around the sun (suspected by Pythagoras) in favor of centuries-long firm adherence to the Ptolemaic geocentric system; the early acceptance of Natural Selection in spite of its tautological essence and only conjectural supporting evidence, because it justified contemporaneous social-political ideologies as typified by, e.g., Spencer and Malthus. Economic, social, and cultural factors are cited as providing the ground, i.e., ideational substrate, for what is cited as the Discreetness-Chance Paradigm (DCP), that has increasingly dominated physics, biology, and medicine for over a century and which invokes small, discrete packets of energy/matter (quanta, genes, microorganisms, aberrant cells) functioning within an environment of statistical, not determined, causality. There is speculation on a possible paradigmatic shift from the DCP, which has fostered the proliferation, parallel with ("splitting") taxonomy, of alleged individual disease entities, their diagnoses, and, when available, their specific remedies, something particularly prominent in, e.g., psychiatry's Diagnostic and Statistical Manual, a codified compendium of alleged mental and behavioral disorders, but evident in any textbook of diagnosis and treatment of physical ailments. This presumed paradigm shift may be reflected in Western medicine, presently increasingly empirical and atomized, towards a growing acceptance of a more generalized, subject-oriented, approach to health and disease, a non

  15. Pursuing the method of multiple working hypotheses for hydrological modeling

    Science.gov (United States)

    Clark, M. P.; Kavetski, D.; Fenicia, F.

    2012-12-01

    Ambiguities in the representation of environmental processes have manifested themselves in a plethora of hydrological models, differing in almost every aspect of their conceptualization and implementation. The current overabundance of models is symptomatic of an insufficient scientific understanding of environmental dynamics at the catchment scale, which can be attributed to difficulties in measuring and representing the heterogeneity encountered in natural systems. This presentation advocates using the method of multiple working hypotheses for systematic and stringent testing of model alternatives in hydrology. We discuss how the multiple hypothesis approach provides the flexibility to formulate alternative representations (hypotheses) describing both individual processes and the overall system. When combined with incisive diagnostics to scrutinize multiple model representations against observed data, this provides hydrologists with a powerful and systematic approach for model development and improvement. Multiple hypothesis frameworks also support a broader coverage of the model hypothesis space and hence improve the quantification of predictive uncertainty arising from system and component non-identifiabilities. As part of discussing the advantages and limitations of multiple hypothesis frameworks, we critically review major contemporary challenges in hydrological hypothesis-testing, including exploiting different types of data to investigate the fidelity of alternative process representations, accounting for model structure ambiguities arising from major uncertainties in environmental data, quantifying regional differences in dominant hydrological processes, and the grander challenge of understanding the self-organization and optimality principles that may functionally explain and describe the heterogeneities evident in most environmental systems. We assess recent progress in these research directions, and how new advances are possible using multiple hypothesis

  16. Advances in the phylogenesis of Agaricales and its higher ranks and strategies for establishing phylogenetic hypotheses.

    Science.gov (United States)

    Zhao, Rui-Lin; Desjardin, Dennis E; Soytong, Kasem; Hyde, Kevin D

    2008-10-01

    We present an overview of previous research results on the molecular phylogenetic analyses in Agaricales and its higher ranks (Agaricomycetes/Agaricomycotina/Basidiomycota) along with the most recent treatments of taxonomic systems in these taxa. Establishing phylogenetic hypotheses using DNA sequences, from which an understanding of the natural evolutionary relationships amongst clades may be derived, requires a robust dataset. It has been recognized that single-gene phylogenies may not truly represent organismal phylogenies, but the concordant phylogenetic genealogies from multiple-gene datasets can resolve this problem. The genes commonly used in mushroom phylogenetic research are summarized.

  17. Adverse psychosocial consequences: Compassion fatigue, burnout and vicarious traumatization: Are nurses who provide palliative and hematological cancer care vulnerable?

    Directory of Open Access Journals (Sweden)

    Brenda M Sabo

    2008-01-01

    Full Text Available The work environment significantly affects the physical, psychological, emotional and/or spiritual wellbeing of individuals is unquestionable. Adverse effects have been noted among healthcare professionals working with clients experiencing pain and suffering often associated with cancer, palliative or end-of-life care; however, little is known about how or in which manner the nurse-patient-family relationship may affect the psychosocial health and wellbeing of nurses working in these areas. Three concepts have been highlighted as most frequently associated with the adverse consequences of caring work: these are compassion fatigue (secondary traumatic stress, burnout and vicarious traumatization. The following discussion investigates these concepts and their implications on palliative and hematological cancer nursing practice.

  18. Vicarious trial-and-error behavior and hippocampal cytochrome oxidase activity during Y-maze discrimination learning in the rat.

    Science.gov (United States)

    Hu, Dan; Xu, Xiaojuan; Gonzalez-Lima, Francisco

    2006-03-01

    The present study investigated whether more vicarious trial-and-error (VTE) behavior, defined by head movement from one stimulus to another at a choice point during simultaneous discriminations, led to better visual discrimination learning in a Y-maze, and whether VTE behavior was a function of the hippocampus by measuring regional brain cytochrome oxidase (C.O.) activity, an index of neuronal metabolic activity. The results showed that the more VTEs a rat made, the better the rat learned the visual discrimination. Furthermore, both learning and VTE behavior during learning were correlated to C.O. activity in the hippocampus, suggesting that the hippocampus plays a role in VTE behavior during discrimination learning.

  19. Investigating the Use of Vicarious and Mastery Experiences in Influencing Early Childhood Education Majors' Self-Efficacy Beliefs

    Science.gov (United States)

    Bautista, Nazan Uludag

    2011-06-01

    This study investigated the effectiveness of an Early Childhood Education science methods course that focused exclusively on providing various mastery (i.e., enactive, cognitive content, and cognitive pedagogical) and vicarious experiences (i.e., cognitive self-modeling, symbolic modeling, and simulated modeling) in increasing preservice elementary teachers' self-efficacy beliefs. Forty-four preservice elementary teachers participated in the study. Analysis of the quantitative (STEBI-b) and qualitative (informal surveys) data revealed that personal science teaching efficacy and science teaching outcome expectancy beliefs increased significantly over the semester. Enactive mastery, cognitive pedagogical mastery, symbolic modeling, and cognitive self-modeling were the major sources of self-efficacy. This list was followed by cognitive content mastery and simulated modeling. This study has implications for science teacher educators.

  20. The relations between violence exposure, posttraumatic stress symptoms, secondary traumatization, vicarious post traumatic growth and illness attribution among psychiatric nurses.

    Science.gov (United States)

    Zerach, Gad; Shalev, Tal Ben-Itzchak

    2015-06-01

    This study examined posttraumatic stress disorder symptoms (PTSD), secondary traumatization (ST) and vicarious posttraumatic growth (VG) among Israeli psychiatric nurses (PN) who were compared to community nurses (CN). Furthermore, we examined the contribution of PN perceptions of the etiology of their patients' mental illness to their PTSD, ST and VG. Results show that PN reported higher levels of both PTSD and ST symptoms, but lower levels of VG, as compare to CN. While ST symptoms were positively related to VG among CN, PTSD and ST symptoms were negatively associated among PN. Finally, exposure to patients' violence, PTSD or ST symptoms, and illness attribution dimensions of 'powerful others', predicted nurses' VG. PN are an at-risk population for work-related stress residues. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Masticatory-stress hypotheses and the supraorbital region of primates.

    Science.gov (United States)

    Hylander, W L; Picq, P G; Johnson, K R

    1991-09-01

    The purpose of this study is to test various masticatory-stress hypotheses about the evolution and function of well-developed browridges of higher primates. This was done by measuring and analyzing patterns of in vivo bone strain recorded from three-element rosette strain gages bonded to the supraorbital region and to other portions of the bony face of Macaca fascicularis and Papio anubis during mastication and incision. The magnitude and direction of the principal strains recorded support Endo's hypothesis that the supraorbital region during mastication and incision is bent in the frontal plane (Endo, 1966). Our data do not, however, support his hypothesis that the supraorbital region is bent more during incision than during mastication. The data also demonstrate that overall levels of supraorbital strain are not larger in more prognathic subjects. Most importantly, the data indicate that the supraorbital region of nonhuman catarrhines is strained very little during mastication and incision. This indicates that there is much more supraorbital bone than is necessary both to counter masticatory loads and to provide an adequate safety factor to failure for these loads. This in turn suggests that the macaque and baboon browridges can be considerably reduced in size and still maintain these required structural characteristics. Thus, our experiments provide no support whatsoever for those hypotheses that directly link browridge morphology to masticatory stress (cf. Endo, 1966; Russell, 1983, 1985). A recent review of Endo's original work indicates that this latter statement is also true for humans (Picq and Hylander, 1989). We conclude, therefore, that there is no good reason to believe that enlarged browridges in living and/or fossil primates are structural adaptations to counter intense masticatory forces. The evolution of browridge morphology in primates is best explained on the basis of factors related to the position of the brain relative to the orbits (Moss and

  2. Origin of honeycombs: Testing the hydraulic and case hardening hypotheses

    Science.gov (United States)

    Bruthans, Jiří; Filippi, Michal; Slavík, Martin; Svobodová, Eliška

    2018-02-01

    Cavernous weathering (cavernous rock decay) is a global phenomenon, which occurs in porous rocks around the world. Although honeycombs and tafoni are considered to be the most common products of this complex process, their origin and evolution are as yet not fully understood. The two commonly assumed formation hypotheses - hydraulic and case hardening - were tested to elucidate the origin of honeycombs on sandstone outcrops in a humid climate. Mechanical and hydraulic properties of the lips (walls between adjacent pits) and backwalls (bottoms of pits) of the honeycombs were determined via a set of established and novel approaches. While the case hardening hypothesis was not supported by the determinations of either tensile strength, drilling resistance or porosity, the hydraulic hypothesis was clearly supported by field measurements and laboratory tests. Fluorescein dye visualization of capillary zone, vapor zone, and evaporation front upon their contact, demonstrated that the evaporation front reaches the honeycomb backwalls under low water flow rate, while the honeycomb lips remain dry. During occasional excessive water flow events, however, the evaporation front may shift to the lips, while the backwalls become moist as a part of the capillary zone. As the zone of evaporation corresponds to the zone of potential salt weathering, it is the spatial distribution of the capillary and vapor zones which dictates whether honeycombs are created or the rock surface is smoothed. A hierarchical model of factors related to the hydraulic field was introduced to obtain better insights into the process of cavernous weathering.

  3. A perspective on SIDS pathogenesis. The hypotheses: plausibility and evidence

    Directory of Open Access Journals (Sweden)

    Goldwater Paul N

    2011-05-01

    Full Text Available Abstract Several theories of the underlying mechanisms of Sudden Infant Death Syndrome (SIDS have been proposed. These theories have born relatively narrow beach-head research programs attracting generous research funding sustained for many years at expense to the public purse. This perspective endeavors to critically examine the evidence and bases of these theories and determine their plausibility; and questions whether or not a safe and reasoned hypothesis lies at their foundation. The Opinion sets specific criteria by asking the following questions: 1. Does the hypothesis take into account the key pathological findings in SIDS? 2. Is the hypothesis congruent with the key epidemiological risk factors? 3. Does it link 1 and 2? Falling short of any one of these answers, by inference, would imply insufficient grounds for a sustainable hypothesis. Some of the hypotheses overlap, for instance, notional respiratory failure may encompass apnea, prone sleep position, and asphyxia which may be seen to be linked to co-sleeping. For the purposes of this paper, each element will be assessed on the above criteria.

  4. Exploration of miRNA families for hypotheses generation.

    KAUST Repository

    Kamanu, T.K.

    2013-10-15

    Technological improvements have resulted in increased discovery of new microRNAs (miRNAs) and refinement and enrichment of existing miRNA families. miRNA families are important because they suggest a common sequence or structure configuration in sets of genes that hint to a shared function. Exploratory tools to enhance investigation of characteristics of miRNA families and the functions of family-specific miRNA genes are lacking. We have developed, miRNAVISA, a user-friendly web-based tool that allows customized interrogation and comparisons of miRNA families for hypotheses generation, and comparison of per-species chromosomal distribution of miRNA genes in different families. This study illustrates hypothesis generation using miRNAVISA in seven species. Our results unveil a subclass of miRNAs that may be regulated by genomic imprinting, and also suggest that some miRNA families may be species-specific, as well as chromosome- and/or strand-specific.

  5. Drug-Resistant Epilepsy: Multiple Hypotheses, Few Answers

    Directory of Open Access Journals (Sweden)

    Fei Tang

    2017-07-01

    Full Text Available Epilepsy is a common neurological disorder that affects over 70 million people worldwide. Despite the recent introduction of new antiseizure drugs (ASDs, about one-third of patients with epilepsy have seizures refractory to pharmacotherapy. Early identification of patients who will become refractory to ASDs could help direct such patients to appropriate non-pharmacological treatment, but the complexity in the temporal patterns of epilepsy could make such identification difficult. The target hypothesis and transporter hypothesis are the most cited theories trying to explain refractory epilepsy, but neither theory alone fully explains the neurobiological basis of pharmacoresistance. This review summarizes evidence for and against several major theories, including the pharmacokinetic hypothesis, neural network hypothesis, intrinsic severity hypothesis, gene variant hypothesis, target hypothesis, and transporter hypothesis. The discussion is mainly focused on the transporter hypothesis, where clinical and experimental data are discussed on multidrug transporter overexpression, substrate profiles of ASDs, mechanism of transporter upregulation, polymorphisms of transporters, and the use of transporter inhibitors. Finally, future perspectives are presented for the improvement of current hypotheses and the development of treatment strategies as guided by the current understanding of refractory epilepsy.

  6. New Vehicle Detection Method with Aspect Ratio Estimation for Hypothesized Windows

    Directory of Open Access Journals (Sweden)

    Jisu Kim

    2015-12-01

    Full Text Available All kinds of vehicles have different ratios of width to height, which are called the aspect ratios. Most previous works, however, use a fixed aspect ratio for vehicle detection (VD. The use of a fixed vehicle aspect ratio for VD degrades the performance. Thus, the estimation of a vehicle aspect ratio is an important part of robust VD. Taking this idea into account, a new on-road vehicle detection system is proposed in this paper. The proposed method estimates the aspect ratio of the hypothesized windows to improve the VD performance. Our proposed method uses an Aggregate Channel Feature (ACF and a support vector machine (SVM to verify the hypothesized windows with the estimated aspect ratio. The contribution of this paper is threefold. First, the estimation of vehicle aspect ratio is inserted between the HG (hypothesis generation and the HV (hypothesis verification. Second, a simple HG method named a signed horizontal edge map is proposed to speed up VD. Third, a new measure is proposed to represent the overlapping ratio between the ground truth and the detection results. This new measure is used to show that the proposed method is better than previous works in terms of robust VD. Finally, the Pittsburgh dataset is used to verify the performance of the proposed method.

  7. Twelve testable hypotheses on the geobiology of weathering.

    Science.gov (United States)

    Brantley, S L; Megonigal, J P; Scatena, F N; Balogh-Brunstad, Z; Barnes, R T; Bruns, M A; Van Cappellen, P; Dontsova, K; Hartnett, H E; Hartshorn, A S; Heimsath, A; Herndon, E; Jin, L; Keller, C K; Leake, J R; McDowell, W H; Meinzer, F C; Mozdzer, T J; Petsch, S; Pett-Ridge, J; Pregitzer, K S; Raymond, P A; Riebe, C S; Shumaker, K; Sutton-Grier, A; Walter, R; Yoo, K

    2011-03-01

    Critical Zone (CZ) research investigates the chemical, physical, and biological processes that modulate the Earth's surface. Here, we advance 12 hypotheses that must be tested to improve our understanding of the CZ: (1) Solar-to-chemical conversion of energy by plants regulates flows of carbon, water, and nutrients through plant-microbe soil networks, thereby controlling the location and extent of biological weathering. (2) Biological stoichiometry drives changes in mineral stoichiometry and distribution through weathering. (3) On landscapes experiencing little erosion, biology drives weathering during initial succession, whereas weathering drives biology over the long term. (4) In eroding landscapes, weathering-front advance at depth is coupled to surface denudation via biotic processes. (5) Biology shapes the topography of the Critical Zone. (6) The impact of climate forcing on denudation rates in natural systems can be predicted from models incorporating biogeochemical reaction rates and geomorphological transport laws. (7) Rising global temperatures will increase carbon losses from the Critical Zone. (8) Rising atmospheric P(CO2) will increase rates and extents of mineral weathering in soils. (9) Riverine solute fluxes will respond to changes in climate primarily due to changes in water fluxes and secondarily through changes in biologically mediated weathering. (10) Land use change will impact Critical Zone processes and exports more than climate change. (11) In many severely altered settings, restoration of hydrological processes is possible in decades or less, whereas restoration of biodiversity and biogeochemical processes requires longer timescales. (12) Biogeochemical properties impart thresholds or tipping points beyond which rapid and irreversible losses of ecosystem health, function, and services can occur. © 2011 Blackwell Publishing Ltd.

  8. Declining scaup populations: issues, hypotheses, and research needs

    Science.gov (United States)

    Austin, J.E.; Afton, A.D.; Anderson, M.G.; Clark, R.G.; Custer, Christine M.; Lawrence, J.S.; Pollard, J.B.; Ringelman, J.K.

    2000-01-01

    The population estimate for greater (Aythya marila) and lesser (Aythya affinis) scaup (combined) has declined dramatically since the early 1980s to record lows in 1998. The 1998 estimate of 3.47 million scaup is far below the goal of 6.3 million set in the North American Waterfowl Management Plan (NAWMP), causing concern among biologists and hunters. We summarize issuesof concern, hypotheses for factors contributing to the population decline, and research and management needs recommended by participants of the Scaup Workshop, held in September 1999. We believe that contaminants, lower female survival, and reduced recruitment due to changes in food resources or breedingground habitats are primary factors contributing to the decline. These factors are not mutually exclusive but likely interact across seasons. Workshop participants identified seven action items. We need to further delineate where declines in breeding populations have occurred, with a primary focus on the western Canadian boreal forest, where declines appear to be most pronounced. Productivity in various areas and habitats throughout the breeding range needs to be assessed by conducting retrospective analyses of existing data and by intensive field studies at broad and local scales. Annual and seasonal survival rates need to be determined in order to assess the role of harvest or natural mortality. Effects of contaminants on reproduction, female body condition, and behavior must be investigated. Use, distribution, and role of food resources relative to body condition and reproduction need to be examined to better understand seasonal dynamics of nutrient reserves and the role in reproductive success. Affiliations among breeding, migration, and wintering areas must be assessed in order to understand differential exposure to harvest or contaminants, and differential reproductive success and recruitment. Biologists and agencies need to gather and improve information needed to manage greater and lesser

  9. How the mainstream limits the spreading of alternative hypotheses

    Science.gov (United States)

    Kalenda, Pavel

    2014-05-01

    that prof. Djuric had tried for more than 10 years to publish this article in various peer-reviewed journals. So, prof. Djuric got into the official book (list) of "scientific dissidents" among hundreds of other professors and doctors of science (De Climont 2012). These "scientific dissidents" do not have access to established journals and may possibly publish privately or at best on the web in marginal journals whose list was published by De Climont (2012). Such a marginal journal in the field of geophysics and geology is New Concepts in Global Tectonics. This journal has been established because the current hypothesis about the movement of the continents due to convection currents in the mantle becomes under the weight of new observation quite untenable. 4) Scientific consensus History has known many hypotheses that were accepted as proven truth but later, in the light of new knowledge, they completely failed. - No one has the right to decide which scientific hypotheses will be accepted and which will not get into print. Perhaps the worst situation is in climatology (due to global effects and impacts), when the plenary session of IPCC consensually stated that the current global warming was mainly due to the human activity. References De Climont, J. (2012): The worldwide list of dissident scientists. http://astrojan.hostei.com/droa.htm. Djurič, J. (2006): Unification Of Gravitation And Electromagnetism. http://jovandjuric.tripod.com/ David H. Douglass, John R. Christy, Benjamin D. Pearson and S. Fred Singer (2007): A comparison of tropical temperature trends with model predictions. International Journal of Climatology, Volume 28, Issue 13, 15 November 2008, Pages: 1693-1701. http://onlinelibrary.wiley.com/doi/10.1002/joc.1651/pdf. Einstein, A. : List of scientific publications by Albert Einstein. /wiki/List_of_scientific_publications_by_Albert_Einstein. Kolínský, P., Valenta, J. and Gaždová, R. (2012): Seismicity, groundwater level variations and earth tides in

  10. Effects over time of self-reported direct and vicarious racial discrimination on depressive symptoms and loneliness among Australian school students.

    Science.gov (United States)

    Priest, Naomi; Perry, Ryan; Ferdinand, Angeline; Kelaher, Margaret; Paradies, Yin

    2017-02-03

    Racism and racial discrimination are increasingly acknowledged as a critical determinant of health and health inequalities. However, patterns and impacts of racial discrimination among children and adolescents remain under-investigated, including how different experiences of racial discrimination co-occur and influence health and development over time. This study examines associations between self-reported direct and vicarious racial discrimination experiences and loneliness and depressive symptoms over time among Australian school students. Across seven schools, 142 students (54.2% female), age at T1 from 8 to 15 years old (M = 11.14, SD = 2.2), and from diverse racial/ethnic and migration backgrounds (37.3% born in English-speaking countries as were one or both parents) self-reported racial discrimination experiences (direct and vicarious) and mental health (depressive symptoms and loneliness) at baseline and 9 months later at follow up. A full cross-lagged panel design was modelled using MPLUS v.7 with all variables included at both time points. A cross-lagged effect of perceived direct racial discrimination on later depressive symptoms and on later loneliness was found. As expected, the effect of direct discrimination on both health outcomes was unidirectional as mental health did not reciprocally influence reported racism. There was no evidence that vicarious racial discrimination influenced either depressive symptoms or loneliness beyond the effect of direct racial discrimination. Findings suggest direct racial discrimination has a persistent effect on depressive symptoms and loneliness among school students over time. Future work to explore associations between direct and vicarious discrimination is required.

  11. Career Coaches as a Source of Vicarious Learning for Racial and Ethnic Minority PhD Students in the Biomedical Sciences: A Qualitative Study.

    Science.gov (United States)

    Williams, Simon N; Thakore, Bhoomi K; McGee, Richard

    2016-01-01

    Many recent mentoring initiatives have sought to help improve the proportion of underrepresented racial and ethnic minorities (URMs) in academic positions across the biomedical sciences. However, the intractable nature of the problem of underrepresentation suggests that many young scientists may require supplemental career development beyond what many mentors are able to offer. As an adjunct to traditional scientific mentoring, we created a novel academic career "coaching" intervention for PhD students in the biomedical sciences. To determine whether and how academic career coaches can provide effective career-development-related learning experiences for URM PhD students in the biomedical sciences. We focus specifically on vicarious learning experiences, where individuals learn indirectly through the experiences of others. The intervention is being tested as part of a longitudinal randomized control trial (RCT). Here, we describe a nested qualitative study, using a framework approach to analyze data from a total of 48 semi-structured interviews from 24 URM PhD students (2 interviews per participant, 1 at baseline, 1 at 12-month follow-up) (16 female, 8 male; 11 Black, 12 Hispanic, 1 Native-American). We explored the role of the coach as a source of vicarious learning, in relation to the students' goal of being future biomedical science faculty. Coaches were resources through which most students in the study were able to learn vicariously about how to pursue, and succeed within, an academic career. Coaches were particularly useful in instances where students' research mentors are unable to provide such vicarious learning opportunities, for example because the mentor is too busy to have career-related discussions with a student, or because they have, or value, a different type of academic career to the type the student hopes to achieve. Coaching can be an important way to address the lack of structured career development that students receive in their home training

  12. Career Coaches as a Source of Vicarious Learning for Racial and Ethnic Minority PhD Students in the Biomedical Sciences: A Qualitative Study

    Science.gov (United States)

    Williams, Simon N.; Thakore, Bhoomi K.; McGee, Richard

    2016-01-01

    Introduction Many recent mentoring initiatives have sought to help improve the proportion of underrepresented racial and ethnic minorities (URMs) in academic positions across the biomedical sciences. However, the intractable nature of the problem of underrepresentation suggests that many young scientists may require supplemental career development beyond what many mentors are able to offer. As an adjunct to traditional scientific mentoring, we created a novel academic career “coaching” intervention for PhD students in the biomedical sciences. Objective To determine whether and how academic career coaches can provide effective career-development-related learning experiences for URM PhD students in the biomedical sciences. We focus specifically on vicarious learning experiences, where individuals learn indirectly through the experiences of others. Method The intervention is being tested as part of a longitudinal randomized control trial (RCT). Here, we describe a nested qualitative study, using a framework approach to analyze data from a total of 48 semi-structured interviews from 24 URM PhD students (2 interviews per participant, 1 at baseline, 1 at 12-month follow-up) (16 female, 8 male; 11 Black, 12 Hispanic, 1 Native-American). We explored the role of the coach as a source of vicarious learning, in relation to the students’ goal of being future biomedical science faculty. Results Coaches were resources through which most students in the study were able to learn vicariously about how to pursue, and succeed within, an academic career. Coaches were particularly useful in instances where students’ research mentors are unable to provide such vicarious learning opportunities, for example because the mentor is too busy to have career-related discussions with a student, or because they have, or value, a different type of academic career to the type the student hopes to achieve. Implications Coaching can be an important way to address the lack of structured career

  13. Vicarious calibration of the multiviewing channel polarisation imager (3MI) of the EUMETSAT Polar System-Second Generation (EPS-SG)

    Science.gov (United States)

    Marbach, T.; Fougnie, B.; Lacan, A.; Schlüssel, P.

    2016-10-01

    The Multi-Viewing -Channel -Polarization Imager (3MI), planned to fly on the Metop-SG satellite as part of the EPS-SG programme in the timeframe beyond 2020, is a radiometer dedicated to aerosol and cloud characterization for climate monitoring, atmospheric composition, air quality and numerical weather prediction. The purpose of the 3MI is to provide multi-spectral (12 channels between 410 and 2130 nm), multi-polarization (-60°, 0°, and +60°), and multi-angular (10 to 14 views) images of the Earth top of atmosphere outgoing radiance. 3MI does not have an onboard calibration facility and its radiometric and geometric performance will rely on vicarious calibration. The aim of this paper is to present the state of the art of vicarious calibration methods applicable to 3MI. The 3MI measurement principle is based on the French atmospheric mission PARASOL (Polarization and Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar) heritage [1]. This allows adapting the vicarious calibration methods of the PARASOL mission to the needs of 3MI. However, the monitoring of the SWIR (short wave infrared) channels will be a new challenge for the 3MI calibration as this spectral range was not present on PARASOL. The cross-calibration with other instruments flying on the same satellite will support the calibration of 3MI. Indeed the Metop-SG payload includes two other optical instruments covering the same spectral regions. METimage and Sentinel-5 will both be equipped with on-board calibration capabilities and provide valuable measurements for vicarious calibration of 3MI. Further cross-calibration with Earth observation instruments on other satellites, will be studied.

  14. The Impact of Enactive /Vicarious pre-reading Tasks on Reading Comprehension and Self-Efficacy of Iranian Pre-Intermediate EFL Learners

    Directory of Open Access Journals (Sweden)

    Arezoo Eshghipour

    2016-01-01

    Full Text Available This study investigated the effect of enactive pre-reading tasks on Iranian pre-intermediate EFL learners’ reading comprehension and self-efficacy. Moreover, it explored whether Iranian per-intermediate EFL learners’ reading comprehension and self-efficacy are influenced by vicarious pre-reading tasks. The required data was gathered through a reading comprehension passage entailing 20 comprehension questions and a 30-item self-efficacy questionnaire with 5-point Likert-scale response options. A total of 66 participants (including 34 individuals in the enactive group and 32 leaners in the vicarious one took part in this study. The Pearson formula, an independent T-Test, paired T-test, and the Mann-Whitney U test were used to analyze the data. Based on the findings of the study, enactive pre-reading tasks played a key role in the Iranian pre-intermediate EFL learners’ reading comprehension ability. Moreover, it was found that vicarious pre-reading tasks served an important role in the Iranian pre-intermediate EFL learners’ self-efficacy.

  15. Female Swedish backpackers in Vietnam: a hypotheses generating study on sexual health risks while travelling.

    Science.gov (United States)

    Dahlman, Disa; Stafström, Martin

    2013-01-01

    According to previous studies, foreign travellers and backpackers are at increased risk of sexually transmitted infections (STI). Concurrently, STI incidence, especially Chlamydia, is increasing among young Swedes. Our objective was to investigate Swedish backpackers' own view of sexual health and risks while travelling, with the purpose to identify hypotheses for further, more extensive research. In-depth semi-structured interviews were carried out in Vietnam with four Swedish women in their early twenties. The interviewees had been travelling throughout South East Asia for a period of at least two weeks. There were large differences between the respondents regarding perceived health risks in relation to food safety, STI, and alcohol and drug use; and to what extent their behaviour while travelling deviated from their normal one. In contrast, the interviewees shared a perceived lack of knowledge about sexual health abroad. The study identified six hypotheses and suggestions for preventive measures that could be analysed in future research. The study demonstrated that sexual behaviour as well as attitudes and norms were strongly linked to the individual level, rather than to the group of backpackers. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. No evidence for bilingual cognitive advantages: A test of four hypotheses.

    Science.gov (United States)

    von Bastian, Claudia C; Souza, Alessandra S; Gade, Miriam

    2016-02-01

    The question whether being bilingual yields cognitive benefits is highly controversial with prior studies providing inconsistent results. Failures to replicate the bilingual advantage have been attributed to methodological factors such as comparing dichotomous groups and measuring cognitive abilities separately with single tasks. Therefore, the authors evaluated the 4 most prominent hypotheses of bilingual advantages for inhibitory control, conflict monitoring, shifting, and general cognitive performance by assessing bilingualism on 3 continuous dimensions (age of acquisition, proficiency, and usage) in a sample of 118 young adults and relating it to 9 cognitive abilities each measured by multiple tasks. Linear mixed-effects models accounting for multiple sources of variance simultaneously and controlling for parents' education as an index of socioeconomic status revealed no evidence for any of the 4 hypotheses. Hence, the authors' results suggest that bilingual benefits are not as broad and as robust as has been previously claimed. Instead, earlier effects were possibly due to task-specific effects in selective and often small samples. PsycINFO Database Record (c) 2016 APA, all rights reserved.

  17. Comments and hypotheses on the mechanism of methane against ischemia/reperfusion injury

    Directory of Open Access Journals (Sweden)

    He Li

    2017-01-01

    Full Text Available As we all know, methane is a kind of fuel. Previous studies have shown that methanogens in the colon can react with carbon dioxide and hydrogen to produce methane. In a recent study, the anti-inflammatory effects of methane were shown in a dog model of small intestinal ischemia/reperfusion. The mechanism of this anti-inflammatory effect needs further investigation. Recently, studies have shown anti-inflammatory, anti-apoptotic and anti-oxidative effects of methane on different organic injuries. According to the results of these studies, we hypothesize that the initial effects of methane are to react with free radicals and enhance expression of antioxidase through forkhead box transcription factor class O pathway. The anti-inflammatory effect is following the anti-oxidative effect, and the anti-apoptotic effect relies on anti-inflammatory and anti-oxidative effects.

  18. Assaults on Inmates and Staff by Perpetrators of Intimate Partner Homicide: An Examination of Competing Hypotheses.

    Science.gov (United States)

    Sorensen, Jonathan R; Vigen, Mark P; Woods, S O; Williams, Bradley D

    2015-11-01

    The current study presents the results of an analysis of serious and assaultive prison rule violating behavior among male perpetrators of intimate partner homicide (IPH). Data on prison rule violations were collected from a sample of 189 inmates convicted of IPH in a large, southern prison system. The study focused on the degree of continuity in violent behavior among IPH offenders from the community to the prison setting. The current study tested hypotheses derived from both the feminist perspective (FP) and the general violence perspective (GVP). As a group, IPH offenders were better behaved in prison than other incarcerated homicide offenders, thereby offering some support for the FP. However, the lower level of assaultive behavior among the group was not universal. Characteristics associated with continued violent offending in the prison environment were the same as those found in previous studies of incarcerated homicide offenders, thereby lending greater support to the GVP. © The Author(s) 2014.

  19. Significance of ecological vicariance and long-distance dispersal in the diversification of Carex sect. Spirostachyae (Cyperaceae).

    Science.gov (United States)

    Escudero, Marcial; Valcárcel, Virginia; Vargas, Pablo; Luceño, Modesto

    2009-11-01

    Plant disjunctions have provided one of the most intriguing distribution patterns historically addressed by biogeographers. Carex sect. Spirostachyae (Cyperaceae) displays an interesting pattern of disjunction to evaluate these scenarios, with species occurring in the main continental landmasses and in oceanic islands of the two hemispheres. Internal transcribed spacer and 5'-trnK intron plastid gene sequences were analyzed to determine (1) the times of diversification using penalized likelihood, and (2) reconstructions of the regions using maximum likelihood and Bayesian approaches of origin of sect. Spirostachyae and internal main lineages. The times for the diversification of sect. Spirostachyae are dated to between the end of the Eocene and the Oligocene, whereas the two main lineages are dated to between the end of the Oligocene and the beginning of Miocene. The phylogenetic analyses reveal a Mediterranean-Eurasian center of differentiation for sect. Spirostachyae and subsection Spirostachyae, whereas no clear, single ancestral area could be inferred for subsection Elatae. Both long-distance dispersal and ecological vicariance appear to have been involved in the evolutionary history of the disjunct distribution of the main lineages of sect. Spirostachyae. These organisms appear to have a special ability to colonize remote areas (through transoceanic and interhemispherical colonizations), but special long-distance dispersal mechanisms are not evident.

  20. Left Prefrontal Activity Reflects the Ability of Vicarious Fear Learning: A Functional Near-Infrared Spectroscopy Study

    Directory of Open Access Journals (Sweden)

    Qingguo Ma

    2013-01-01

    Full Text Available Fear could be acquired indirectly via social observation. However, it remains unclear which cortical substrate activities are involved in vicarious fear transmission. The present study was to examine empathy-related processes during fear learning by-proxy and to examine the activation of prefrontal cortex by using functional near-infrared spectroscopy. We simultaneously measured participants’ hemodynamic responses and skin conductance responses when they were exposed to a movie. In this movie, a demonstrator (i.e., another human being was receiving a classical fear conditioning. A neutral colored square paired with shocks (CSshock and another colored square paired with no shocks (CSno-shock were randomly presented in front of the demonstrator. Results showed that increased concentration of oxygenated hemoglobin in left prefrontal cortex was observed when participants watched a demonstrator seeing CSshock compared with that exposed to CSno-shock. In addition, enhanced skin conductance responses showing a demonstrator's aversive experience during learning object-fear association were observed. The present study suggests that left prefrontal cortex, which may reflect speculation of others’ mental state, is associated with social fear transmission.

  1. Left prefrontal activity reflects the ability of vicarious fear learning: a functional near-infrared spectroscopy study.

    Science.gov (United States)

    Ma, Qingguo; Huang, Yujing; Wang, Lei

    2013-01-01

    Fear could be acquired indirectly via social observation. However, it remains unclear which cortical substrate activities are involved in vicarious fear transmission. The present study was to examine empathy-related processes during fear learning by-proxy and to examine the activation of prefrontal cortex by using functional near-infrared spectroscopy. We simultaneously measured participants' hemodynamic responses and skin conductance responses when they were exposed to a movie. In this movie, a demonstrator (i.e., another human being) was receiving a classical fear conditioning. A neutral colored square paired with shocks (CS(shock)) and another colored square paired with no shocks (CS(no-shock)) were randomly presented in front of the demonstrator. Results showed that increased concentration of oxygenated hemoglobin in left prefrontal cortex was observed when participants watched a demonstrator seeing CS(shock) compared with that exposed to CS(no-shock). In addition, enhanced skin conductance responses showing a demonstrator's aversive experience during learning object-fear association were observed. The present study suggests that left prefrontal cortex, which may reflect speculation of others' mental state, is associated with social fear transmission.

  2. Disentangling dispersal, vicariance and adaptive radiation patterns: a case study using armyworms in the pest genus Spodoptera (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Kergoat, Gael J; Prowell, Dorothy P; Le Ru, Bruno P; Mitchell, Andrew; Dumas, Pascaline; Clamens, Anne-Laure; Condamine, Fabien L; Silvain, Jean-François

    2012-12-01

    Thanks to the recent development of integrative approaches that combine dated phylogenies with models of biogeographic evolution, it is becoming more feasible to assess the roles of dispersal and vicariance in creating complex patterns of geographical distribution. However, the historical biogeography of taxa with good dispersal abilities, like birds or flying insects, still remains largely unknown because of the lack of complete phylogenies accompanied by robust estimates of divergence times. In this study, we investigate the evolution and historical biogeography of the globally distributed pest genus Spodoptera (Lepidoptera: Noctuidae) using complete taxon sampling and an extensive set of analyses. Through the analysis of a combined morphological and molecular dataset, we provide the first robust phylogenetic framework for this widespread and economically important group of moths. Historical biogeography approaches indicate that dispersal events have been the driving force in the biogeographic history of the group. One of the most interesting findings of this study is the probable occurrence of two symmetric long-distance dispersal events between the Afrotropical and the Neotropical region, which appear to have occurred in the late Miocene. Even more remarkably, our dated phylogenies reveal that the diversification of the clade that includes specialist grass feeders has followed closely the expansion of grasslands in the Miocene, similar to the adaptive radiation of specialist grazing mammals during the same period. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Assessing the impact of vicarious experiences on preservice elementary science teacher efficacy and preservice elementary teacher efficacy

    Science.gov (United States)

    Wagler, Ronald Robert

    Scope and method of study. The purpose of this study was to investigate the impact of vicarious experiences (preservice teacher field experiences) on perceived preservice science teacher efficacy and perceived preservice teacher efficacy. The participants for the study were 46 preservice elementary education students who were enrolled in CIED 3430 (Early Lab and Clinical Experience in Elementary Education II) at a large Midwestern state university and 20 classroom inservice teachers. A pretest was administered early in the spring 2007 semester, before the preservice teachers did their field experience and consisted of demographic questions and the STEBI-B. A posttest was administered at the end of the spring 2007 semester, after the preservice teachers had completed their field experiences, and consisted of demographic questions, a rating of the teachers they observed during their educational field experience, the STEBI-B and the TES. The field experience classroom inservice teachers provided personal, professional, and classroom data in the middle of the spring 2007 semester. All data were analyzed using analysis of variance (ANOVA) and analysis of covariance (ANCOVA). Findings and conclusions. Factors of gender, ethnicity, socioeconomic status and preservice teacher program placement were found to be significant predictors of preservice teachers' efficacy scores. Even though, in some cases, these factors negatively impacted preservice teacher efficacy, preservice teachers should be placed in these environments when support is most available. The Teacher Efficacy Scale (Gibson & Dembo, 1984) is invalid. Even the construct of a general teacher efficacy is questionable.

  4. Individual differences in the impact of vicarious racism: African American students react to the George Zimmerman trial.

    Science.gov (United States)

    Mason, Tyler B; Maduro, Ralitsa S; Derlega, Valerian J; Hacker, Desi S; Winstead, Barbara A; Haywood, Jacqueline E

    2017-04-01

    This research focused on how race-based rejection sensitivity (RS-Race) and components of racial identity intensify negative psychological reactions to an incident of vicarious racism. We examined how these individual difference variables directly and/or indirectly predicted African American students' reactions to the trial of George Zimmerman in the killing of the African American teenager, Trayvon Martin. In Study 1, 471 African American students completed measures of RS-Race, thought intrusions about the Zimmerman trial, and outcome variables (negative affect about the Zimmerman trial and forgiveness for Mr. Zimmerman). In Study 2, 304 African American students completed measures of racial identity (centrality, private regard, and public regard), thought intrusions about the Zimmerman trial, negative affect, and forgiveness. In Study 1, higher RS-Race was either directly and/or indirectly (via thought intrusions) related to more negative affect and lower forgiveness. In Study 2, high racial centrality and low public regard either directly and/or indirectly (via thought intrusions) predicted more negative affect and lower forgiveness. RS-Race and specific components of racial identity are likely to sensitize African Americans to incidents of racism that happen to other African Americans, leading to negative psychological reactions when these events occur. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  5. Do we represent intentional action as recursively embedded? The answer must be empirical. A comment on Vicari and Adenzato (2014).

    Science.gov (United States)

    Martins, Mauricio D; Fitch, W Tecumseh

    2015-12-15

    The relationship between linguistic syntax and action planning is of considerable interest in cognitive science because many researchers suggest that "motor syntax" shares certain key traits with language. In a recent manuscript in this journal, Vicari and Adenzato (henceforth VA) critiqued Hauser, Chomsky and Fitch's 2002 (henceforth HCF's) hypothesis that recursion is language-specific, and that its usage in other domains is parasitic on language resources. VA's main argument is that HCF's hypothesis is falsified by the fact that recursion typifies the structure of intentional action, and recursion in the domain of action is independent of language. Here, we argue that VA's argument is incomplete, and that their formalism can be contrasted with alternative frameworks that are equally consistent with existing data. Therefore their conclusions are premature without further empirical testing and support. In particular, to accept VA's argument it would be necessary to demonstrate both that humans in fact represent self-embedding in the structure of intentional action, and that language is not used to construct these representations. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Observing tutorial dialogues collaboratively: insights about human tutoring effectiveness from vicarious learning.

    Science.gov (United States)

    Chi, Michelene T H; Roy, Marguerite; Hausmann, Robert G M

    2008-03-01

    The goals of this study are to evaluate a relatively novel learning environment, as well as to seek greater understanding of why human tutoring is so effective. This alternative learning environment consists of pairs of students collaboratively observing a videotape of another student being tutored. Comparing this collaboratively observing environment to four other instructional methods-one-on-one human tutoring, observing tutoring individually, collaborating without observing, and studying alone-the results showed that students learned to solve physics problems just as effectively from observing tutoring collaboratively as the tutees who were being tutored individually. We explain the effectiveness of this learning environment by postulating that such a situation encourages learners to become active and constructive observers through interactions with a peer. In essence, collaboratively observing combines the benefit of tutoring with the benefit of collaborating. The learning outcomes of the tutees and the collaborative observers, along with the tutoring dialogues, were used to further evaluate three hypotheses explaining why human tutoring is an effective learning method. Detailed analyses of the protocols at several grain sizes suggest that tutoring is effective when tutees are independently or jointly constructing knowledge: with the tutor, but not when the tutor independently conveys knowledge. 2008 Cognitive Science Society, Inc.

  7. Deterrence's Element of Sanction Certainty: Friendships, Vicarious Experiences, and Underage Alcohol Use.

    Science.gov (United States)

    Mowen, Thomas J; Boman, John H

    2018-01-09

    Underage drinking remains a pressing issue on college campuses across the United States. Though the most common form of addressing underage alcohol use on campuses is through deterrence-based policies, evidence suggests deterrence-based methods are ineffective and may produce negative outcomes. Using dyadic data, the objective of this study is to use a friendship-informed perspective on deterrence theory to examine how an individual's and his/her friend's perceptions of sanction certainty relate to self-reported underage alcohol use. Using multilevel mixed models which fall under the actor-partner interdependence modeling class, results demonstrate that respondents who perceive high levels of sanction certainty drink and heavily use alcohol more frequently than those who perceive low levels of sanction certainty. Additionally, those who have friends who perceive high levels of sanction certainty tend to drink at young ages significantly more frequently and in more dangerous patterns than those who have friends who perceive a low sanction certainty. The dyad members' levels of sanction certainty do not interact in relation to alcohol use. The significant relationships of the friends' sanction certainty support the notion of friendship-based deterrence. However, the consistent positive direction of all sanction certainty measures is the opposite of what deterrence theory hypothesizes. As such, it appears that deterrence is not only ineffective at stopping underage alcohol use on college campuses, but may be harmful due to increased rates of both drinking and high-risk drinking.

  8. Religiosity, Heavy Alcohol Use, and Vicarious Learning Networks among Adolescents in the United States

    Science.gov (United States)

    Gryczynski, Jan; Ward, Brian W.

    2012-01-01

    Previous research has found that religiosity may protect against risky alcohol and drug use behaviors among adolescents, but the social mechanics underpinning the relationship are not well understood. This study examined the relationship between religiosity, heavy drinking, and social norms among U.S. adolescents aged 12 to 17 years, using the…

  9. Placental complications after a previous cesarean section

    OpenAIRE

    Milošević Jelena; Lilić Vekoslav; Tasić Marija; Radović-Janošević Dragana; Stefanović Milan; Antić Vladimir

    2009-01-01

    Introduction The incidence of cesarean section has been rising in the past 50 years. With the increased number of cesarean sections, the number of pregnancies with the previous cesarean section rises as well. The aim of this study was to establish the influence of the previous cesarean section on the development of placental complications: placenta previa, placental abruption and placenta accreta, as well as to determine the influence of the number of previous cesarean sections on the complic...

  10. Sin nombre virus and rodent species diversity: a test of the dilution and amplification hypotheses.

    Science.gov (United States)

    Clay, Christine A; Lehmer, Erin M; Jeor, Stephen St; Dearing, M Denise

    2009-07-31

    Species diversity is proposed to greatly impact the prevalence of pathogens. Two predominant hypotheses, the "Dilution Effect" and the "Amplification Effect", predict divergent outcomes with respect to the impact of species diversity. The Dilution Effect predicts that pathogen prevalence will be negatively correlated with increased species diversity, while the Amplification Effect predicts that pathogen prevalence will be positively correlated with diversity. For many host-pathogen systems, the relationship between diversity and pathogen prevalence has not be empirically examined. We tested the Dilution and Amplification Effect hypotheses by examining the prevalence of Sin Nombre virus (SNV) with respect to diversity of the nocturnal rodent community. SNV is directly transmitted primarily between deer mice (Peromyscus maniculatus). Using mark-recapture sampling in the Spring and Fall of 2003-2005, we measured SNV prevalence in deer mice at 16 landscape level sites (3.1 hectares each) that varied in rodent species diversity. We explored several mechanisms by which species diversity may affect SNV prevalence, including reduced host density, reduced host persistence, the presence of secondary reservoirs and community composition. We found a negative relationship between species diversity and SNV prevalence in deer mice, thereby supporting the Dilution Effect hypothesis. Deer mouse density and persistence were lower at sites with greater species diversity; however, only deer mouse persistence was positively correlated with SNV prevalence. Pinyon mice (P. truei) may serve as dilution agents, having a negative effect on prevalence, while kangaroo rats (Dipodomys ordii), may have a positive effect on the prevalence of SNV, perhaps through effects on deer mouse behavior. While previous studies on host-pathogen systems have found patterns of diversity consistent with either the Dilution or Amplification Effects, the mechanisms by which species diversity influences

  11. Support for major hypotheses in invasion biology is uneven and declining

    Directory of Open Access Journals (Sweden)

    Jonathan Jeschke

    2012-08-01

    Full Text Available Several major hypotheses have been proposed to explain and predict biological invasions, but the general applicability of these hypotheses is largely unknown, as most of them have not been evaluated using a standard approach across taxonomic groups and habitats. We offer such an evaluation for six selected leading hypotheses. Our global literature review reveals that those hypotheses that consider interactions of exotic invaders with their new environment (invasional meltdown, novel weapons, enemy release are better supported by empirical evidence than other hypotheses (biotic resistance, island susceptibility, tens rule. We also show that empirical support for the six hypotheses has declined over time, and that support differs among taxonomic groups and habitats. Our results have implications for basic and applied research, policy making, and invasive species management, as their effectiveness depends on sound hypotheses.

  12. Out of Arabia: A Complex Biogeographic History of Multiple Vicariance and Dispersal Events in the Gecko Genus Hemidactylus (Reptilia: Gekkonidae)

    Science.gov (United States)

    Šmíd, Jiří; Carranza, Salvador; Kratochvíl, Lukáš; Gvoždík, Václav; Nasher, Abdul Karim; Moravec, Jiří

    2013-01-01

    The geological history of the Arabian Peninsula has played a crucial role in shaping current diversity and distribution patterns of many Arabian and African faunal elements. The gecko genus Hemidactylus is not an exception. In this study, we provide an insight into the phylogeny and systematics of 45 recognized species of the so-called Arid clade of the genus Hemidactylus from Arabia, the Horn of Africa, the Levant and Iran. The material comprises 358 specimens sequenced for up to two mitochondrial (12S rRNA, cytochrome b) and four nuclear (mc1r, cmos, rag1, rag2) genes with 4766 bp of the concatenated alignment length. A robust calibrated phylogeny and reconstruction of historical biogeography are inferred. We link the history of this genus with major geological events that occurred in the region within the last 30 million years. Two basal divergences correspond with the break-ups of the Arabian and African landmasses and subsequent separation of Socotra from the Arabian mainland, respectively, segregating the genus by means of vicariance. Formation of the Red Sea led to isolation and subsequent radiation in the Arabian Peninsula, which was followed by multiple independent expansions: 13.1 Ma to Iran; 9.8 Ma to NE Africa; 8.2 to Socotra Archipelago; 7–7.3 Ma two colonizations to the Near East; 5.9 Ma to NE Africa; and 4.1 to Socotra. Moreover, using multiple genetic markers we detected cryptic diversity within the genus, particularly in south-western Arabia and the Ethiopian highlands, and confirmed the existence of at least seven new species in the area. These findings highlight the role of Arabia and the Horn of Africa as an important Hemidactylus diversity hotspot. PMID:23724016

  13. Mom feels what her child feels: thermal signatures of vicarious autonomic response while watching children in a stressful situation

    Directory of Open Access Journals (Sweden)

    Barbara eManini

    2013-06-01

    Full Text Available Maternal attunement with an infant's emotional states is thought to represent a distinctive feature of the human primary bond. It implies the mother’s ability of empathizing with her child in order to fulfil the child’s needs in an immediate and appropriate manner. Thus, it is particularly involved in stressful situations. By assuming that maternal attunement embodies a direct sharing of physiological responses with the child, we compared the autonomic response of mothers observing their own distressed child with those of other women observing an unknown child involved in an ecological distressful condition (mishap paradigm. The hypothesis was that the adult’s response was more attuned with the child’s response in the former group than in the latter group. The autonomic response was non-invasively evaluated through the recording of the thermal facial imprints by means of thermal infrared (IR imaging. Nine mother-child dyads and nine woman-unknown child dyads were studied. We found marked similarities between the facial temperature dynamics of women and children along the experimental procedure, thus providing evidence for a direct emotional sharing within the adult-child dyad. The evidence for common dynamics in the time course of the temperatures was assessed through correlation analysis and, nevertheless, resulted stronger in the mother-child dyads than in the other women–child dyads. In addition, temporal analysis showed a faster response in mothers than in other women, thus confirming our study hypothesis. Besides confirming the extraordinary capability of thermal infrared imaging to preserve ecological context in the study of social or non-verbal interactions, these results suggest that maternity appears to potentiate the emotional attunement with the child. Although based on preliminary results, this study opens new perspectives in the study of the factors modulating vicarious socio-emotional processes.

  14. Glacial vicariance in the Pacific Northwest: evidence from a lodgepole pine mitochondrial DNA minisatellite for multiple genetically distinct and widely separated refugia.

    Science.gov (United States)

    Godbout, Julie; Fazekas, Aron; Newton, Craig H; Yeh, Francis C; Bousquet, Jean

    2008-05-01

    The Canadian side of the Pacific Northwest was almost entirely covered by ice during the last glacial maximum, which has induced vicariance and genetic population structure for several plant and animal taxa. Lodgepole pine (Pinus contorta Dougl. ex. Loud.) has a wide latitudinal and longitudinal distribution in the Pacific Northwest. Our main objective was to identify relictual signatures of glacial vicariance in the population structure of the species and search for evidence of distinct glacial refugia in the Pacific Northwest. A maternally inherited mitochondrial DNA minisatellite-like marker was used to decipher haplotype diversity in 91 populations of lodgepole pine located across the natural range. Overall population differentiation was sizeable (G(ST) = 0.365 and R(ST) = 0.568). Four relatively homogeneous groups of populations, possibly representative of as many genetically distinct glacial populations, were identified for the two main subspecies, ssp. latifolia and ssp. contorta. For ssp. contorta, one glacial lineage is suggested to have been located at high latitudes and possibly off the coast of mainland British Columbia (BC), while the other is considered to have been located south of the ice sheet along the Pacific coast. For ssp. latifolia, two genetically distinct glacial populations probably occurred south of the ice sheet: in the area bounded by the Cascades and Rocky Mountains ranges, and on the eastern side of the Rockies. A possible fifth refugium located in the Yukon may have also been present for ssp. latifolia. Zones of contact between these ancestral lineages were also apparent in interior and northern BC. These results indicate the role of the Queen Charlotte Islands and the Alexander Archipelago as a refugial zone for some Pacific Northwest species and the vicariant role played by the Cascades and the American Rocky Mountains during glaciation.

  15. Preoperative screening: value of previous tests.

    Science.gov (United States)

    Macpherson, D S; Snow, R; Lofgren, R P

    1990-12-15

    To determine the frequency of tests done in the year before elective surgery that might substitute for preoperative screening tests and to determine the frequency of test results that change from a normal value to a value likely to alter perioperative management. Retrospective cohort analysis of computerized laboratory data (complete blood count, sodium, potassium, and creatinine levels, prothrombin time, and partial thromboplastin time). Urban tertiary care Veterans Affairs Hospital. Consecutive sample of 1109 patients who had elective surgery in 1988. At admission, 7549 preoperative tests were done, 47% of which duplicated tests performed in the previous year. Of 3096 previous results that were normal as defined by hospital reference range and done closest to the time of but before admission (median interval, 2 months), 13 (0.4%; 95% CI, 0.2% to 0.7%), repeat values were outside a range considered acceptable for surgery. Most of the abnormalities were predictable from the patient's history, and most were not noted in the medical record. Of 461 previous tests that were abnormal, 78 (17%; CI, 13% to 20%) repeat values at admission were outside a range considered acceptable for surgery (P less than 0.001, frequency of clinically important abnormalities of patients with normal previous results with those with abnormal previous results). Physicians evaluating patients preoperatively could safely substitute the previous test results analyzed in this study for preoperative screening tests if the previous tests are normal and no obvious indication for retesting is present.

  16. One-pot regioselective synthesis of nitrophenyloxazolinyl styrene oxides by the Darzens reaction of vicarious nucleophilic substitution-formed carbanions of 2-dichloromethyl-4,4-dimethyloxazoline.

    Science.gov (United States)

    Florio, Saverio; Lorusso, Patrizia; Granito, Catia; Luisi, Renzo; Troisi, Luigino

    2004-07-23

    The vicarious nucleophilic substitution reaction of dichloromethyloxazoline 2 with nitrobenzene has been investigated. Treatment of 2 with t-BuOK followed by the addition of nitrobenzene leads to benzylic carbanions 4 or 9 depending upon the solvent used (DMSO, DMF, or THF). Subsequent treatment of 4 or 9 with aldehydes, in a Darzens-like reaction, furnishes very good yields of nitrophenyl oxazolinyloxiranes 8 and 11. 1,2-Dioxazolinyl-1,2-dinitrophenylethene 7 forms quantitatively when carbanion 4 is allowed to warm to room temperature in the absence of external electrophiles.

  17. Sexual segregation of forage patch use: Support for the social-factors and predation hypotheses.

    Science.gov (United States)

    Biggerstaff, Michael T; Lashley, Marcus A; Chitwood, M Colter; Moorman, Christopher E; DePerno, Christopher S

    2017-03-01

    Nearly all species of sexually dimorphic ungulates sexually segregate. Several hypotheses have been proposed to explain this phenomenon, including the social-factors hypothesis (SFH) and the predation hypothesis (PH). Interestingly, previous studies have accepted and rejected each hypothesis within and across species but few studies have simultaneously tested both hypotheses in the same population. In August 2011 and 2012 using 7680 photographs taken with camera traps in standardized forage patches, we tested two predictions of the SFH: 1) foraging efficiency of both sexes would decrease when foraging rate in mixed-sex groups relative to single-sex groups, and 2) activity patterns (i.e., the pattern of temporal use of forage patches on a diel scale) of the sexes would decrease in temporal overlap at the forage patch level (i.e., social segregation) compared to the overall temporal overlap of activity patterns of the population. Also, we tested two predictions of the +PH : 1) the relationship between feeding rates of each sex, and 2) temporal activity overlap would change with changing risk level of forage patches as a result of differing risk perception between sexes. In support of the SFH for temporal segregation, when in mixed-sex groups, mature males and all females decreased feeding rate 30% and 10%, respectively; further, the sexes had similar activity patterns overall (94-95% overlap), though temporal overlap was lower in individual forage patches (68-74% overlap). In multi-male mixed sex groups, at least one male exhibited aggressive posture toward females during all foraging bouts suggesting intersex aggression was the cause of the observed decrease in foraging rates. In support of the PH , the sexes adjusted feeding rate differently in response to changing risk level of a forage patch, encouraging spatial segregation; however, the PH was not supported for temporal segregation because temporal activity pattern overlap did not vary as a function of predation

  18. Testing Hypotheses on Risk Factors for Scientific Misconduct via Matched-Control Analysis of Papers Containing Problematic Image Duplications.

    Science.gov (United States)

    Fanelli, Daniele; Costas, Rodrigo; Fang, Ferric C; Casadevall, Arturo; Bik, Elisabeth M

    2018-02-19

    It is commonly hypothesized that scientists are more likely to engage in data falsification and fabrication when they are subject to pressures to publish, when they are not restrained by forms of social control, when they work in countries lacking policies to tackle scientific misconduct, and when they are male. Evidence to test these hypotheses, however, is inconclusive due to the difficulties of obtaining unbiased data. Here we report a pre-registered test of these four hypotheses, conducted on papers that were identified in a previous study as containing problematic image duplications through a systematic screening of the journal PLoS ONE. Image duplications were classified into three categories based on their complexity, with category 1 being most likely to reflect unintentional error and category 3 being most likely to reflect intentional fabrication. We tested multiple parameters connected to the hypotheses above with a matched-control paradigm, by collecting two controls for each paper containing duplications. Category 1 duplications were mostly not associated with any of the parameters tested, as was predicted based on the assumption that these duplications were mostly not due to misconduct. Categories 2 and 3, however, exhibited numerous statistically significant associations. Results of univariable and multivariable analyses support the hypotheses that academic culture, peer control, cash-based publication incentives and national misconduct policies might affect scientific integrity. No clear support was found for the "pressures to publish" hypothesis. Female authors were found to be equally likely to publish duplicated images compared to males. Country-level parameters generally exhibited stronger effects than individual-level parameters, because developing countries were significantly more likely to produce problematic image duplications. This suggests that promoting good research practices in all countries should be a priority for the international

  19. Automatic electromagnetic valve for previous vacuum

    International Nuclear Information System (INIS)

    Granados, C. E.; Martin, F.

    1959-01-01

    A valve which permits the maintenance of an installation vacuum when electric current fails is described. It also lets the air in the previous vacuum bomb to prevent the oil ascending in the vacuum tubes. (Author)

  20. Concomitant and previous osteoporotic vertebral fractures.

    Science.gov (United States)

    Lenski, Markus; Büser, Natalie; Scherer, Michael

    2017-04-01

    Background and purpose - Patients with osteoporosis who present with an acute onset of back pain often have multiple fractures on plain radiographs. Differentiation of an acute osteoporotic vertebral fracture (AOVF) from previous fractures is difficult. The aim of this study was to investigate the incidence of concomitant AOVFs and previous OVFs in patients with symptomatic AOVFs, and to identify risk factors for concomitant AOVFs. Patients and methods - This was a prospective epidemiological study based on the Registry of Pathological Osteoporotic Vertebral Fractures (REPAPORA) with 1,005 patients and 2,874 osteoporotic vertebral fractures, which has been running since February 1, 2006. Concomitant fractures are defined as at least 2 acute short-tau inversion recovery (STIR-) positive vertebral fractures that happen concomitantly. A previous fracture is a STIR-negative fracture at the time of initial diagnostics. Logistic regression was used to examine the influence of various variables on the incidence of concomitant fractures. Results - More than 99% of osteoporotic vertebral fractures occurred in the thoracic and lumbar spine. The incidence of concomitant fractures at the time of first patient contact was 26% and that of previous fractures was 60%. The odds ratio (OR) for concomitant fractures decreased with a higher number of previous fractures (OR =0.86; p = 0.03) and higher dual-energy X-ray absorptiometry T-score (OR =0.72; p = 0.003). Interpretation - Concomitant and previous osteoporotic vertebral fractures are common. Risk factors for concomitant fractures are a low T-score and a low number of previous vertebral fractures in cases of osteoporotic vertebral fracture. An MRI scan of the the complete thoracic and lumbar spine with STIR sequence reduces the risk of under-diagnosis and under-treatment.

  1. Automatic Construction of Hypotheses for Linear Objects in Digital and Laser Scanning Images

    Directory of Open Access Journals (Sweden)

    Quintino Dalmolin

    2004-12-01

    Full Text Available This paper presents an automatic road hypotheses approach using digital image and laser scanning image combining various Digital Image Processing techniques. The semantic objects, in this work, are linear features, such as, roads and streets. The aim of this paper is extract automatically road hypotheses on image space and object space for use the information in automatic absolute orientation process. The results show that methodology is efficiency and the roads hypotheses are generate and validate.

  2. Taxonomic hypotheses regarding the genus Gerbillus (Rodentia, Muridae, Gerbillinae) based on molecular analyses of museum specimens

    Science.gov (United States)

    Ndiaye, Arame; Tatard, Caroline; Stanley, William; Granjon, Laurent

    2016-01-01

    Abstract Methodological improvements now allow routine analyses of highly degraded DNA samples as found in museum specimens. Using these methods could be useful in studying such groups as rodents of the genus Gerbillus for which i) the taxonomy is still highly debated, ii) collection of fresh specimens may prove difficult. Here we address precise taxonomic questions using a small portion of the cytochrome b gene obtained from 45 dry skin/skull museum samples (from 1913 to 1974) originating from two African and three Asian countries. The specimens were labelled Gerbillus gerbillus, Gerbillus andersoni, Gerbillus nanus, Gerbillus amoenus, Gerbillus perpallidus and Gerbillus pyramidum, and molecular results mostly confirmed these assignations. The close relationship between Gerbillus nanus (Asian origin) and Gerbillus amoenus (African origin) confirmed that they represent vicariant sibling species which differentiated in allopatry on either side of the Red Sea. In the closely related Gerbillus perpallidus and Gerbillus pyramidum, specimens considered as belonging to one Gerbillus pyramidum subspecies (Gerbillus pyramidum floweri) appeared closer to Gerbillus perpallidus suggesting that they (Gerbillus pyramidum floweri and Gerbillus perpallidus) may represent a unique species, distributed on both sides of the Nile River, for which the correct name should be Gerbillus floweri. Furthermore, the three other Gerbillus pyramidum subspecies grouped together with no apparent genetic structure suggesting that they may not yet represent genetically differentiated lineages. This study confirms the importance of using these methods on museum samples, which can open new perspectives in this particular group as well as in other groups of interest. PMID:27047247

  3. Testing Adaptive Hypotheses of Convergence with Functional Landscapes: A Case Study of Bone-Cracking Hypercarnivores

    Science.gov (United States)

    Tseng, Zhijie Jack

    2013-01-01

    Morphological convergence is a well documented phenomenon in mammals, and adaptive explanations are commonly employed to infer similar functions for convergent characteristics. I present a study that adopts aspects of theoretical morphology and engineering optimization to test hypotheses about adaptive convergent evolution. Bone-cracking ecomorphologies in Carnivora were used as a case study. Previous research has shown that skull deepening and widening are major evolutionary patterns in convergent bone-cracking canids and hyaenids. A simple two-dimensional design space, with skull width-to-length and depth-to-length ratios as variables, was used to examine optimized shapes for two functional properties: mechanical advantage (MA) and strain energy (SE). Functionality of theoretical skull shapes was studied using finite element analysis (FEA) and visualized as functional landscapes. The distribution of actual skull shapes in the landscape showed a convergent trend of plesiomorphically low-MA and moderate-SE skulls evolving towards higher-MA and moderate-SE skulls; this is corroborated by FEA of 13 actual specimens. Nevertheless, regions exist in the landscape where high-MA and lower-SE shapes are not represented by existing species; their vacancy is observed even at higher taxonomic levels. Results highlight the interaction of biomechanical and non-biomechanical factors in constraining general skull dimensions to localized functional optima through evolution. PMID:23734244

  4. Evaluation of hypotheses for the cause of the 1886 Charleston earthquake

    Energy Technology Data Exchange (ETDEWEB)

    White, R.M.; Long, L.T. (Law Environmental, Inc., Kennesaw, GA (USA); Georgia Inst. of Tech., Atlanta, GA (USA))

    1989-10-01

    This report describes a geophysical/geological investigation of the earth's crust at seismogenic depths in the Charleston, South Carolina area. This investigation was made for the purpose of narrowing the range of theories that have been used to explain the historic 1886 Charleston earthquake. Since a number of these theories are based on only a portion of the available data, we have established a comprehensive data set in order to allow these hypotheses to be subjected to the entire data set. Specifically, we combined existing and new gravity, magnetic and topographic data in grids of 128 km, 256 km and 1028 km on a side centered on Charleston. Seismic, geologic and drilling data were collected and summarized. A magnetotelluric survey consisting of 12 soundings interpreted to depths of over 40 kilometers defined the bottom of the rigid crust with assistance from seismic reflection and other data. A geologic model of the crust in the area of Charleston was constructed and it defined the locations of Triassic/Jurassic basins Paleozoic plutons in greater detail than has previously been achieved. 102 refs., 75 figs.

  5. Evaluation of hypotheses for the cause of the 1886 Charleston earthquake

    International Nuclear Information System (INIS)

    White, R.M.; Long, L.T.

    1989-10-01

    This report describes a geophysical/geological investigation of the earth's crust at seismogenic depths in the Charleston, South Carolina area. This investigation was made for the purpose of narrowing the range of theories that have been used to explain the historic 1886 Charleston earthquake. Since a number of these theories are based on only a portion of the available data, we have established a comprehensive data set in order to allow these hypotheses to be subjected to the entire data set. Specifically, we combined existing and new gravity, magnetic and topographic data in grids of 128 km, 256 km and 1028 km on a side centered on Charleston. Seismic, geologic and drilling data were collected and summarized. A magnetotelluric survey consisting of 12 soundings interpreted to depths of over 40 kilometers defined the bottom of the rigid crust with assistance from seismic reflection and other data. A geologic model of the crust in the area of Charleston was constructed and it defined the locations of Triassic/Jurassic basins Paleozoic plutons in greater detail than has previously been achieved. 102 refs., 75 figs

  6. Uterine rupture without previous caesarean delivery

    DEFF Research Database (Denmark)

    Thisted, Dorthe L. A.; H. Mortensen, Laust; Krebs, Lone

    2015-01-01

    OBJECTIVE: To determine incidence and patient characteristics of women with uterine rupture during singleton births at term without a previous caesarean delivery. STUDY DESIGN: Population based cohort study. Women with term singleton birth, no record of previous caesarean delivery and planned...... vaginal delivery (n=611,803) were identified in the Danish Medical Birth Registry (1997-2008). Medical records from women recorded with uterine rupture during labour were reviewed to ascertain events of complete uterine rupture. Relative Risk (RR) and adjusted Relative Risk Ratio (aRR) of complete uterine...... rupture with 95% confidence intervals (95% CI) were ascertained according to characteristics of the women and of the delivery. RESULTS: We identified 20 cases with complete uterine rupture. The incidence of complete uterine rupture among women without previous caesarean delivery was about 3...

  7. The impacts of comparative anatomy of electric rays (Batoidea: Torpediniformes) on their systematic hypotheses.

    Science.gov (United States)

    Claeson, Kerin M

    2014-06-01

    The Comparative anatomy of the 11 recognized genera within Torpediniformes is described, systematically categorized, and illustrated in a comprehensive photo-atlas. Data are compiled into a character matrix and cladistically analyzed using parsimony to test hypotheses about the previously recognized subfamilies, while reconstructing the possible evolutionary history of Torpediniformes. Results are consistent with the previous rank-based classifications, regardless of the parsimony criteria used to generate the phylogenetic hypothesis, with one notable exception: a monophyletic Narcininae was never recovered. Torpedinoidea (=Hypnos + Torpedo) is supported by the presence of long, slender, flexible jaw cartilages, absence of a large rostral fontanelle, presence of suprascapular antimeres that are each shorter than the scapular process of the scapulocoracoid, antorbital cartilages that articulate on the anterior aspect of the nasal capsules and absence of a frontoparietal fontanelle. Subfamilial names Hypninae and Torpedininae are redundant with the genus names Hypnos and Torpedo and are not adopted here. Narcinoidea (=nontorpedinoid torpediniforms) is supported by unambiguous character transformations to the presence of a divided lower lip, labial cartilages, laterolingually compressed palatoquadrates, bifurcated antorbital cartilages, a rostral fontanelle, ventrally projecting nasal capsules, a dorsal rim of the synarcual mouth posterior to occipital condyle, posteriorly positioned lateral stays, and obtuse anterior margins of lateral stays. Narkidae is supported by unambiguous character transformations to the presence of an uncovered eye that protrudes above dorsal surface, a shared rim between the spiracle and the eye, an anterior nasal turret that projects ventrally, a nasal curtain that covers the upper lip and dentition when the mouth is closed, tab-like prepelvic processes, a mesopterygium that is shorter than propterygium but longer than metapterygium, a

  8. The effect of the heliospheric current sheet on cosmic ray intensities at solar maximum: Two alternative hypotheses

    International Nuclear Information System (INIS)

    Thomas, B.T.; Goldstein, B.E.; Smith, E.J.

    1986-01-01

    There is now a growing awareness that solar cycle related changes in the large-scale structure of the heliospheric current sheet may play an important role in the modulation of galactic cosmic rays. To date, attention has been focused on the configuration of the current sheet at times near solar minimum when the current sheet structure is relatively simple. Previous analyses have explored the effect on cosmic ray intensities of a single current sheet which is tilted with respect to the heliographic equator under the assumption that the tilt of the current sheet is a minimum at solar minimum and increases as solar maximum approaches. This paper attempts to extend the previous analyses into the period near solar maximum. Two alternative hypotheses are explored: (1) that the tilt of the current sheet continues to increase as solar maximum approaches, finally becoming vertical and overturning, and (2) that the single sheet structure breaks down near solar maximum and the sun at this time sheds the poloidal flux of the previous cycle and develops a new field structure of the opposite polarity. It is found that both hypotheses lead to variations in cosmic ray intensity comparable to those actually observed over the solar cycle

  9. INTRODUCTION Previous reports have documented a high ...

    African Journals Online (AJOL)

    pregnancy if they were married, educated, had dental insurance, previously used dental services when not pregnant, or had knowledge about the possible connection between oral health and pregnancy outcome8. The purpose of this study was to explore the factors determining good oral hygiene among pregnant women ...

  10. Empowerment perceptions of educational managers from previously ...

    African Journals Online (AJOL)

    The perceptions of educational manag ers from previously disadvantaged primary and high schools in the Nelson Mandela Metropole regarding the issue of empowerment are outlined and the perceptions of educational managers in terms of various aspects of empowerment at different levels reflected. A literature study ...

  11. Management of choledocholithiasis after previous gastrectomy.

    Science.gov (United States)

    Anwer, S; Egan, R; Cross, N; Guru Naidu, S; Somasekar, K

    2017-09-01

    Common bile duct stones in patients with a previous gastrectomy can be a technical challenge because of the altered anatomy. This paper presents the successful management of two such patients using non-traditional techniques as conventional endoscopic retrograde cholangiopancreatography was not possible.

  12. Laboratory Grouping Based on Previous Courses.

    Science.gov (United States)

    Doemling, Donald B.; Bowman, Douglas C.

    1981-01-01

    In a five-year study, second-year human physiology students were grouped for laboratory according to previous physiology and laboratory experience. No significant differences in course or board examination performance were found, though correlations were found between predental grade-point averages and grouping. (MSE)

  13. Intelligence, previous convictions and interrogative suggestibility: a path analysis of alleged false-confession cases.

    Science.gov (United States)

    Sharrock, R; Gudjonsson, G H

    1993-05-01

    The main purpose of this study was to investigate the relationship between interrogative suggestibility and previous convictions among 108 defendants in criminal trials, using a path analysis technique. It was hypothesized that previous convictions, which may provide defendants with interrogative experiences, would correlate negatively with 'shift' as measured by the Gudjonsson Suggestibility Scale (Gudjonsson, 1984a), after intelligence and memory had been controlled for. The hypothesis was partially confirmed and the theoretical and practical implications of the findings are discussed.

  14. Advances in the phylogenesis of Agaricales and its higher ranks and strategies for establishing phylogenetic hypotheses§

    Science.gov (United States)

    Zhao, Rui-lin; Desjardin, Dennis E.; Soytong, Kasem; Hyde, Kevin D.

    2008-01-01

    We present an overview of previous research results on the molecular phylogenetic analyses in Agaricales and its higher ranks (Agaricomycetes/Agaricomycotina/Basidiomycota) along with the most recent treatments of taxonomic systems in these taxa. Establishing phylogenetic hypotheses using DNA sequences, from which an understanding of the natural evolutionary relationships amongst clades may be derived, requires a robust dataset. It has been recognized that single-gene phylogenies may not truly represent organismal phylogenies, but the concordant phylogenetic genealogies from multiple-gene datasets can resolve this problem. The genes commonly used in mushroom phylogenetic research are summarized. PMID:18837104

  15. Evaluation of Inequality Constrained Hypotheses Using an Akaike-Type Information Criterion

    NARCIS (Netherlands)

    Altinisik, Y.

    2018-01-01

    The Akaike information criterion (AIC) is one of the best known information criteria that can be used to evaluate hypotheses containing only equality restrictions on model parameters. The GORIC is a generalization of the AIC that can be utilized to evaluate hypotheses containing equality and/or

  16. Black/White Differences in Adolescent Drug Use: A Test of Six Hypotheses

    Science.gov (United States)

    Rote, Sunshine M.; Taylor, John

    2014-01-01

    Six specific hypotheses have been developed to account for why Caucasians have higher rates of drug use compared to African-Americans. This article utilizes data from a South Florida-based community study of 893 young adults (1998-2002) to test these hypotheses. Specifically, Caucasians (1) initiate drug use at younger ages than African-Americans…

  17. Research publications in the field of health: omission of hypotheses and presentation of common-sense conclusions

    Directory of Open Access Journals (Sweden)

    Egberto Ribeiro Turato

    Full Text Available CONTEXT AND OBJECTIVE: Medical literature should consist of knowledge applicable to professional education; nevertheless, the profusion of articles in databases provokes disquiet among students. The authors considered the premise that scientific production in the field of health follows a mechanical description of phenomena without the clarity of motivating questions. The aim was to interpret material from expert reports, applied by medical students to analyze articles from renowned journals. DESIGN AND SETTING: This research project was exploratory, searching for latent meanings regarding methodological problems in a sample of papers. It was performed in a Brazilian medical school. METHODS: The sample was intentionally built, consisting of articles related to original research in the field of health, published over the previous five years. The results came from text content analysis, performed by a professor and his medical students. RESULTS: (1 Failure to state a hypothesis is an equivocal practice: articles did not show clarity of hypothesis to demonstrate that their authors had epistemological knowledge of the methods chosen. (2 There is a certain belief that in normal scientific practice, hypotheses are unnecessary: studies without explicit hypotheses led to suppositions that they merely repeat dominant models. (3 Presentation of common sense as scientific conclusions: research brings together what would have mobilized the researchers initially. CONCLUSIONS: Absence of formal hypotheses leaves scientific production vulnerable when put under epistemological discussion. Conclusions from scientific articles are often confounded with common-sense statements. Quantitative research is suggested, for studying the frequency of occurrence of these dubious methodological points.

  18. Proteomics Analysis Reveals Previously Uncharacterized Virulence Factors in Vibrio proteolyticus

    Directory of Open Access Journals (Sweden)

    Ann Ray

    2016-07-01

    Full Text Available Members of the genus Vibrio include many pathogens of humans and marine animals that share genetic information via horizontal gene transfer. Hence, the Vibrio pan-genome carries the potential to establish new pathogenic strains by sharing virulence determinants, many of which have yet to be characterized. Here, we investigated the virulence properties of Vibrio proteolyticus, a Gram-negative marine bacterium previously identified as part of the Vibrio consortium isolated from diseased corals. We found that V. proteolyticus causes actin cytoskeleton rearrangements followed by cell lysis in HeLa cells in a contact-independent manner. In search of the responsible virulence factor involved, we determined the V. proteolyticus secretome. This proteomics approach revealed various putative virulence factors, including active type VI secretion systems and effectors with virulence toxin domains; however, these type VI secretion systems were not responsible for the observed cytotoxic effects. Further examination of the V. proteolyticus secretome led us to hypothesize and subsequently demonstrate that a secreted hemolysin, belonging to a previously uncharacterized clan of the leukocidin superfamily, was the toxin responsible for the V. proteolyticus-mediated cytotoxicity in both HeLa cells and macrophages. Clearly, there remains an armory of yet-to-be-discovered virulence factors in the Vibrio pan-genome that will undoubtedly provide a wealth of knowledge on how a pathogen can manipulate host cells.

  19. Previously unknown organomagnesium compounds in astrochemical context

    OpenAIRE

    Ruf, Alexander

    2018-01-01

    We describe the detection of dihydroxymagnesium carboxylates (CHOMg) in astrochemical context. CHOMg was detected in meteorites via ultrahigh-resolving chemical analytics and represents a novel, previously unreported chemical class. Thus, chemical stability was probed via quantum chemical computations, in combination with experimental fragmentation techniques. Results propose the putative formation of green-chemical OH-Grignard-type molecules and triggered fundamental questions within chemica...

  20. [Placental complications after a previous cesarean section].

    Science.gov (United States)

    Milosević, Jelena; Lilić, Vekoslav; Tasić, Marija; Radović-Janosević, Dragana; Stefanović, Milan; Antić, Vladimir

    2009-01-01

    The incidence of cesarean section has been rising in the past 50 years. With the increased number of cesarean sections, the number of pregnancies with the previous cesarean section rises as well. The aim of this study was to establish the influence of the previous cesarean section on the development of placental complications: placenta previa, placental abruption and placenta accreta, as well as to determine the influence of the number of previous cesarean sections on the complication development. The research was conducted at the Clinic of Gynecology and Obstetrics in Nis covering 10-year-period (from 1995 to 2005) with 32358 deliveries, 1280 deliveries after a previous cesarean section, 131 cases of placenta previa and 118 cases of placental abruption. The experimental groups was presented by the cases of placenta previa or placental abruption with prior cesarean section in obstetrics history, opposite to the control group having the same conditions but without a cesarean section in medical history. The incidence of placenta previa in the control group was 0.33%, opposite to the 1.86% incidence after one cesarean section (pcesarean sections and as high as 14.28% after three cesarean sections in obstetric history. Placental abruption was recorded as placental complication in 0.33% pregnancies in the control group, while its incidence was 1.02% after one cesarean section (pcesarean sections. The difference in the incidence of intrapartal hysterectomy between the group with prior cesarean section (0.86%) and without it (0.006%) shows a high statistical significance (pcesarean section is an important risk factor for the development of placental complications.

  1. Field Trips--Vicariously?

    Science.gov (United States)

    Pendered, Norman C.

    1975-01-01

    Cost and scheduling problems often prevent industrial arts teachers from taking their students on field trips. Moreover, study findings indicate that the highly valued industrial visit proves less effective than flexible, inexpensive, custom-tailored slide-tape presentations. Slide-tape preparation procedures are outlined, and recommendations are…

  2. The missing link of Jewish European ancestry: contrasting the Rhineland and the Khazarian hypotheses.

    Science.gov (United States)

    Elhaik, Eran

    2013-01-01

    The question of Jewish ancestry has been the subject of controversy for over two centuries and has yet to be resolved. The "Rhineland hypothesis" depicts Eastern European Jews as a "population isolate" that emerged from a small group of German Jews who migrated eastward and expanded rapidly. Alternatively, the "Khazarian hypothesis" suggests that Eastern European Jews descended from the Khazars, an amalgam of Turkic clans that settled the Caucasus in the early centuries CE and converted to Judaism in the 8th century. Mesopotamian and Greco-Roman Jews continuously reinforced the Judaized empire until the 13th century. Following the collapse of their empire, the Judeo-Khazars fled to Eastern Europe. The rise of European Jewry is therefore explained by the contribution of the Judeo-Khazars. Thus far, however, the Khazars' contribution has been estimated only empirically, as the absence of genome-wide data from Caucasus populations precluded testing the Khazarian hypothesis. Recent sequencing of modern Caucasus populations prompted us to revisit the Khazarian hypothesis and compare it with the Rhineland hypothesis. We applied a wide range of population genetic analyses to compare these two hypotheses. Our findings support the Khazarian hypothesis and portray the European Jewish genome as a mosaic of Near Eastern-Caucasus, European, and Semitic ancestries, thereby consolidating previous contradictory reports of Jewish ancestry. We further describe a major difference among Caucasus populations explained by the early presence of Judeans in the Southern and Central Caucasus. Our results have important implications for the demographic forces that shaped the genetic diversity in the Caucasus and for medical studies.

  3. Books average previous decade of economic misery.

    Science.gov (United States)

    Bentley, R Alexander; Acerbi, Alberto; Ormerod, Paul; Lampos, Vasileios

    2014-01-01

    For the 20(th) century since the Depression, we find a strong correlation between a 'literary misery index' derived from English language books and a moving average of the previous decade of the annual U.S. economic misery index, which is the sum of inflation and unemployment rates. We find a peak in the goodness of fit at 11 years for the moving average. The fit between the two misery indices holds when using different techniques to measure the literary misery index, and this fit is significantly better than other possible correlations with different emotion indices. To check the robustness of the results, we also analysed books written in German language and obtained very similar correlations with the German economic misery index. The results suggest that millions of books published every year average the authors' shared economic experiences over the past decade.

  4. Induced vaginal birth after previous caesarean section

    Directory of Open Access Journals (Sweden)

    Akylbek Tussupkaliyev

    2016-11-01

    Full Text Available Introduction The rate of operative birth by Caesarean section is constantly rising. In Kazakhstan, it reaches 27 per cent. Research data confirm that the percentage of successful vaginal births after previous Caesarean section is 50–70 per cent. How safe the induction of vaginal birth after Caesarean (VBAC remains unclear. Methodology The studied techniques of labour induction were amniotomy of the foetal bladder with the vulsellum ramus, intravaginal administration of E1 prostaglandin (Misoprostol, and intravenous infusion of Oxytocin-Richter. The assessment of rediness of parturient canals was conducted by Bishop’s score; the labour course was assessed by a partogram. The effectiveness of labour induction techniques was assessed by the number of administered doses, the time of onset of regular labour, the course of labour and the postpartum period and the presence of complications, and the course of the early neonatal period, which implied the assessment of the child’s condition, described in the newborn development record. The foetus was assessed by medical ultrasound and antenatal and intranatal cardiotocography (CTG. Obtained results were analysed with SAS statistical processing software. Results The overall percentage of successful births with intravaginal administration of Misoprostol was 93 per cent (83 of cases. This percentage was higher than in the amniotomy group (relative risk (RR 11.7 and was similar to the oxytocin group (RR 0.83. Amniotomy was effective in 54 per cent (39 of cases, when it induced regular labour. Intravenous oxytocin infusion was effective in 94 per cent (89 of cases. This percentage was higher than that with amniotomy (RR 12.5. Conclusions The success of vaginal delivery after previous Caesarean section can be achieved in almost 70 per cent of cases. At that, labour induction does not decrease this indicator and remains within population boundaries.

  5. New Observations of Crustal Plateau Surface Histories, Venus: Implications for Crustal Plateau Hypotheses

    Science.gov (United States)

    Hansen, V. L.

    2005-03-01

    Geohistories documented for four crustal plateaus surface presents challenges to both downwelling and plume hypotheses of plateau formation, and lead to a third hypothesis, plateau formation involving crystallization of a huge lava pond.

  6. Corrigendum to: Bayesian evaluation of informative hypotheses in SEM using Mplus

    NARCIS (Netherlands)

    van de Schoot, R.; Verhoeven, Marjolein; Hoijtink, H.

    2014-01-01

    This paper corrects: van de Schoot, R., Verhoeven, M., & Hoijtink, H. (2013). Bayesian evaluation ofinformative hypotheses in SEM using Mplus: A black bear story. EuropeanJournal of Developmental Psychology, 10, 81 –98.

  7. A criterion for testing hypotheses about the covariance function of a stationary Gaussian stochastic process

    OpenAIRE

    Kozachenko, Yuriy; Troshki, Viktor

    2015-01-01

    We consider a measurable stationary Gaussian stochastic process. A criterion for testing hypotheses about the covariance function of such a process using estimates for its norm in the space $L_p(\\mathbb {T}),\\,p\\geq1$, is constructed.

  8. Testing contingency hypotheses in budgetary research: An evaluation of the use of moderated regression analysis

    NARCIS (Netherlands)

    Hartmann, Frank G.H.; Moers, Frank

    1999-01-01

    In the contingency literature on the behavioral and organizational effects of budgeting, use of the Moderated Regression Analysis (MRA) technique is prevalent. This technique is used to test contingency hypotheses that predict interaction effects between budgetary and contextual variables. This

  9. Comparison for aphasic and control subjects of eye movements hypothesized in neurolinguistic programming.

    Science.gov (United States)

    Dooley, K O; Farmer, A

    1988-08-01

    Neurolinguistic programming's hypothesized eye movements were measured independently using videotapes of 10 nonfluent aphasic and 10 control subjects matched for age and sex. Chi-squared analysis indicated that eye-position responses were significantly different for the groups. Although earlier research has not supported the hypothesized eye positions for normal subjects, the present findings support the contention that eye-position responses may differ between neurologically normal and aphasic individuals.

  10. Influence of Previous Knowledge in Torrance Tests of Creative Thinking

    Directory of Open Access Journals (Sweden)

    María Aranguren

    2015-07-01

    Full Text Available The aim of this work is to analyze the influence of study field, expertise and recreational activities participation in Torrance Tests of Creative Thinking (TTCT, 1974 performance. Several hypotheses were postulated to explore the possible effects of previous knowledge in TTCT verbal and TTCT figural university students’ outcomes. Participants in this study included 418 students from five study fields: Psychology;Philosophy and Literature, Music; Engineering; and Journalism and Advertising (Communication Sciences. Results found in this research seem to indicate that there in none influence of the study field, expertise and recreational activities participation in neither of the TTCT tests. Instead, the findings seem to suggest some kind of interaction between certain skills needed to succeed in specific studies fields and performance on creativity tests, such as the TTCT. These results imply that TTCT is a useful and valid instrument to measure creativity and that some cognitive process involved in innovative thinking can be promoted using different intervention programs in schools and universities regardless the students study field.

  11. Proteomics Analysis Reveals Previously Uncharacterized Virulence Factors in Vibrio proteolyticus.

    Science.gov (United States)

    Ray, Ann; Kinch, Lisa N; de Souza Santos, Marcela; Grishin, Nick V; Orth, Kim; Salomon, Dor

    2016-07-26

    Members of the genus Vibrio include many pathogens of humans and marine animals that share genetic information via horizontal gene transfer. Hence, the Vibrio pan-genome carries the potential to establish new pathogenic strains by sharing virulence determinants, many of which have yet to be characterized. Here, we investigated the virulence properties of Vibrio proteolyticus, a Gram-negative marine bacterium previously identified as part of the Vibrio consortium isolated from diseased corals. We found that V. proteolyticus causes actin cytoskeleton rearrangements followed by cell lysis in HeLa cells in a contact-independent manner. In search of the responsible virulence factor involved, we determined the V. proteolyticus secretome. This proteomics approach revealed various putative virulence factors, including active type VI secretion systems and effectors with virulence toxin domains; however, these type VI secretion systems were not responsible for the observed cytotoxic effects. Further examination of the V. proteolyticus secretome led us to hypothesize and subsequently demonstrate that a secreted hemolysin, belonging to a previously uncharacterized clan of the leukocidin superfamily, was the toxin responsible for the V. proteolyticus-mediated cytotoxicity in both HeLa cells and macrophages. Clearly, there remains an armory of yet-to-be-discovered virulence factors in the Vibrio pan-genome that will undoubtedly provide a wealth of knowledge on how a pathogen can manipulate host cells. The pan-genome of the genus Vibrio is a potential reservoir of unidentified toxins that can provide insight into how members of this genus have successfully risen as emerging pathogens worldwide. We focused on Vibrio proteolyticus, a marine bacterium that was previously implicated in virulence toward marine animals, and characterized its interaction with eukaryotic cells. We found that this bacterium causes actin cytoskeleton rearrangements and leads to cell death. Using a

  12. Effect of previous induced abortions on postabortion contraception selection.

    Science.gov (United States)

    Keene, Melissa; Roston, Alicia; Keith, Louis; Patel, Ashlesha

    2015-05-01

    The objective was to compare contraceptive method selection in women undergoing their first pregnancy termination versus women undergoing repeat pregnancy termination in an urban abortion clinic. We hypothesized that women undergoing repeat abortions will select highly effective contraceptives (intrauterine device, subdermal implant, tubal ligation) more often than patients undergoing their first abortion. We conducted a retrospective analysis of all women undergoing first-trimester surgical abortion at John H. Stroger, Jr., Hospital of Cook County from October 1, 2009, to October 31, 2011. We compared contraceptive method selection in the postabortion period after receipt of contraceptive counseling for 7466 women, stratifying women by history of no prior abortion versus one or more abortions. Of the 7466 women, 48.6% (3625) had no history of previous abortion. After controlling for age, race and number of living children, women with a history of abortion were more likely to select a highly effective method [odds ratio (OR) 1.19, 95% confidence interval (CI) 1.06-1.33]. Most significantly, having living children was the strongest predictor of a highly effective method with an OR of 3.17 (95% CI 2.69-3.75). In women having a first-trimester abortion, the factors most predictive of selecting a highly effective method for postabortion contraception include history of previous abortion and having living children. The latter holds true independent of abortion history. This paper is unique in its ability to demonstrate the high interest in highly effective contraceptive selection in high-risk, low-income women with prior abortion history. Efforts to integrate provision of highly effective methods of contraception for postabortion care are essential for the reduction of future unintended pregnancies. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Diel metabolomics analysis of a hot spring chlorophototrophic microbial mat leads to new hypotheses of community member metabolisms

    Directory of Open Access Journals (Sweden)

    Young-Mo eKim

    2015-04-01

    Full Text Available Dynamic environmental factors such as light, nutrients, salt, and temperature continuously affect chlorophototrophic microbial mats, requiring adaptive and acclimative responses to stabilize composition and function. Quantitative metabolomics analysis can provide insights into metabolite dynamics for understanding community response to such changing environmental conditions. In this study, we quantified volatile organic acids, polar metabolites (amino acids, glycolytic and citric acid cycle intermediates, nucleobases, nucleosides, and sugars, wax esters, and polyhydroxyalkanoates, resulting in the identification of 104 metabolites and related molecules in thermal chlorophototrophic microbial mat cores collected over a diel cycle in Mushroom Spring, Yellowstone National Park. A limited number of predominant taxa inhabit this community and their functional potentials have been previously identified through metagenomic and metatranscriptomic analyses and in situ metabolisms, and metabolic interactions among these taxa have been hypothesized. Our metabolomics results confirmed the diel cycling of photorespiration (e.g. glycolate and fermentation (e.g. acetate, propionate, and lactate products, the carbon storage polymers polyhydroxyalkanoates, and dissolved gases (e.g. H2 and CO2 in the waters overlying the mat, which were hypothesized to occur in major mat chlorophototrophic community members. In addition, we have formulated the following new hypotheses: 1 the morning hours are a time of biosynthesis of amino acids, DNA, and RNA; 2 photo-inhibited cells may also produce lactate via fermentation as an alternate metabolism; 3 glycolate and lactate are exchanged among Synechococcus and Roseiflexus spp.; and 4 fluctuations in many metabolite pools (e.g. wax esters at different times of day result from species found at different depths within the mat responding to temporal differences in their niches

  14. Hidden decay of impact after education for self-management of chronic illnesses: hypotheses.

    Science.gov (United States)

    Park, M J; Green, Joseph; Ishikawa, Hirono; Kiuchi, Takahiro

    2013-03-01

    People with chronic illnesses can benefit from self-management education. However, those benefits are said to decay over time (there is some evidence that this 'decay of impact' does occur), and the reinforcements used to prevent that decay appear to be ineffective. We hypothesize that the reinforcements appear to be ineffective because decay of impact occurs only in a subgroup of these programs' participants, so any benefits of reinforcements in that subgroup are concealed by whole-group summary statistics. We also hypothesize that reinforcements can benefit those who need them - those who would otherwise have decay. One approach to testing these hypotheses requires analysis of individual-level data, which is uncommon in this field. Some useful data could come from studies that have already been completed, but the strongest evidence will require prospectively designed tests in future trials. If the hypotheses are false, then time and resources spent on reinforcements can be saved or redirected. If the hypotheses are true, then reinforcements can be implemented with less waste and they can be made more effective. These programs can also be improved to better fit their users' needs, and there can be a new basis for evaluating the programs' effectiveness.

  15. Dreaming and waking experiences in schizophrenia: how should the (dis)continuity hypotheses be approached empirically?

    Science.gov (United States)

    Noreika, Valdas

    2011-06-01

    A number of differences between the dreams of schizophrenia patients and those of healthy participants have been linked to changes in waking life that schizophrenia may cause. This way, the "continuity hypothesis" has become a standard way to relate dreaming and waking experiences in schizophrenia. Nevertheless, some of the findings in dream literature are not compatible with the continuity hypothesis and suggest some other ways how dream content and waking experiences could interact. Conceptually, the continuity hypothesis could be sharpened into the "waking-to-dreaming" and the "dreaming-to-waking" hypotheses, whereas a less explored type of "discontinuity" could embrace the "compensated waking" and the "compensated dreaming" hypotheses. A careful consideration and empirical testing of each of those hypotheses may reveal a multiplicity of the ways how dreaming and waking life interact in schizophrenia. Copyright © 2010 Elsevier Inc. All rights reserved.

  16. Causal null hypotheses of sustained treatment strategies: What can be tested with an instrumental variable?

    Science.gov (United States)

    Swanson, Sonja A; Labrecque, Jeremy; Hernán, Miguel A

    2018-05-02

    Sometimes instrumental variable methods are used to test whether a causal effect is null rather than to estimate the magnitude of a causal effect. However, when instrumental variable methods are applied to time-varying exposures, as in many Mendelian randomization studies, it is unclear what causal null hypothesis is tested. Here, we consider different versions of causal null hypotheses for time-varying exposures, show that the instrumental variable conditions alone are insufficient to test some of them, and describe additional assumptions that can be made to test a wider range of causal null hypotheses, including both sharp and average causal null hypotheses. Implications for interpretation and reporting of instrumental variable results are discussed.

  17. R and D appropriability, opportunity, and market structure: new evidence on some Schumpeterian hypotheses

    Energy Technology Data Exchange (ETDEWEB)

    Levin, R.C.; Cohen, W.M.; Mowery, D.C.

    1985-05-01

    One of the largest bodies of literature in the field of industrial organization is devoted to the interpretation and testing of several hypotheses advanced by Joseph Schumpeter (1950) concerning innovation and industrial market structure. One set of hypotheses focuses on the role of firm size as a determinant of R and D spending and the rate of technological advance. Another set focuses on the effect of market concentration on R and D and technological advance. In this paper, the latter set of hypotheses is reexamined at the industry level, using new data on R and D appropriability and technological opportunity collected by Leven et al. (1984) in a survey of R and D executives in 130 industries. 6 references.

  18. The scientific role of hypotheses and the reasoning of college students in physics problem solving

    Directory of Open Access Journals (Sweden)

    Jenaro Guisasola

    2003-08-01

    Full Text Available This paper attempts to explore how freshmen college students in engineering state hypoteses to build their own problem solving structure when dealing with physics problems. From the constructivist perspective of the teaching and learning process hypotheses stating plays a fundamental role to check the coherence of students' ideas against the theoretical framework. The main instruments to accede to students' reasoning were their written solutions to four problematic situations in which they were asked to state hypotheses. The protocols were analysed according to a standard methodology. In this paper two of such problematic situations and the corresponding cathegorization schemes are presented in addition to reseach findings and conclusions.

  19. Declining forest productivity in aging forest stands: a modeling analysis of alternative hypotheses

    Energy Technology Data Exchange (ETDEWEB)

    Murty, D.; McMurtrie, R. E. [New South Wales Univ., Sydney, NSW (Australia); Ryan, M. G. [Forest Service, Fort Collins, CO (United States). Rocky Mountain Forest and Range Experiment Station

    1996-01-01

    Various hypotheses regarding the decline in forest net primary productivity (NPP) with age in closed-canopy stands were evaluated by graphical analysis using the G`DAY model. Results indicated that the interaction between decline in stomatal conductance, hence photosynthetic efficiency and decline in soil nutrient availability, provided the most plausible answer to reduced productivity, although the relative importance of these two explanations varied according to certain key model assumptions. Increased sapwood respiration, one of the hypotheses tested, was found to have only a minor effect on the decline of forest productivity. 60 refs., 6 figs.

  20. Rates of induced abortion in Denmark according to age, previous births and previous abortions

    Directory of Open Access Journals (Sweden)

    Marie-Louise H. Hansen

    2009-11-01

    Full Text Available Background: Whereas the effects of various socio-demographic determinants on a woman's risk of having an abortion are relatively well-documented, less attention has been given to the effect of previous abortions and births. Objective: To study the effect of previous abortions and births on Danish women's risk of an abortion, in addition to a number of demographic and personal characteristics. Data and methods: From the Fertility of Women and Couples Dataset we obtained data on the number of live births and induced abortions by year (1981-2001, age (16-39, county of residence and marital status. Logistic regression analysis was used to estimate the influence of the explanatory variables on the probability of having an abortion in a relevant year. Main findings and conclusion: A woman's risk of having an abortion increases with the number of previous births and previous abortions. Some interactions were was found in the way a woman's risk of abortion varies with calendar year, age and parity. The risk of an abortion for women with no children decreases while the risk of an abortion for women with children increases over time. Furthermore, the risk of an abortion decreases with age, but relatively more so for women with children compared to childless women. Trends for teenagers are discussed in a separate section.

  1. De bruikbaarheid van de ‘shaken baby syndroom’-hypothese in het strafproces

    NARCIS (Netherlands)

    Hoving, R.A.

    In het Nederlandse strafproces wordt regelmatig gebruik gemaakt van deskundigenbewijs van deskundigen die uitgaan van de ‘shaken baby syndroom’-hypothese om aan te tonen dat een verdachte een baby heeft mishandeld of gedood. In onder meer de Verenigde Staten en Engeland woedt een felle discussie

  2. Gender Relations and Economic Development: Hypotheses about the Reversal of Fortune in EurAsia

    NARCIS (Netherlands)

    de Pleijt, A.M.; van Zanden, J.L.; Carmichael, S.G.

    2016-01-01

    This paper develops an interrelated set of hypotheses about the links between gender relations, family systems and economic development in EurAsia. Firstly, we briefly discuss a number of ideas from the recent literature about the links between gender relations and economic development. Secondly, we

  3. Williams Syndrome Hypersociability: A Neuropsychological Study of the Amygdala and Prefrontal Cortex Hypotheses

    Science.gov (United States)

    Capitao, Liliana; Sampaio, Adriana; Fernandez, Montse; Sousa, Nuno; Pinheiro, Ana; Goncalves, Oscar F.

    2011-01-01

    Individuals with Williams syndrome display indiscriminate approach towards strangers. Neuroimaging studies conducted so far have linked this social profile to structural and/or functional abnormalities in WS amygdala and prefrontal cortex. In this study, the neuropsychological hypotheses of amygdala and prefrontal cortex involvement in WS…

  4. A Comprehensive Framework for Evaluating Hypotheses about Cultural Bias in Educational Testing

    Science.gov (United States)

    Banks, Kathleen

    2006-01-01

    The purpose of this article is to present a working definition of the term "culture," as well as to describe and demonstrate a comprehensive framework for evaluating hypotheses about cultural bias in educational testing. The framework is demonstrated using 5th-grade reading and language arts data from the Terra Nova test (CTB/McGraw-Hill, 1999).…

  5. Disagreement and causal learning: others' hypotheses affect children's evaluations of evidence.

    Science.gov (United States)

    Young, Andrew G; Alibali, Martha W; Kalish, Charles W

    2012-09-01

    When children evaluate evidence and make causal inferences, they are sensitive to the social context in which data are generated. This study investigated whether children learn more from evidence generated by an agent who agrees with them or from one who disagrees with them. Children in two age groups (5- and 6-year-olds and 9- and 10-year-olds) observed the functioning of a machine that lit up and played music in the presence of certain objects. After endorsing one of two plausible causal hypotheses, children observed a puppet either agree or disagree with their own hypotheses. The puppet then generated a further piece of evidence that confirmed, disconfirmed, or was neutral with respect to the children's hypotheses. When they were later asked to make causal inferences about objects they did not directly observe, children in both age groups responded differentially to identical evidence depending on whether the agent agreed or disagreed, and they often drew stronger inferences in response to disagreement. In addition, older children were particularly sensitive to disagreement when the evidence was ambiguous. Our results suggest that children consider the relationship between their own and others' hypotheses when evaluating evidence that others generate. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  6. Support for major hypotheses in invasion biology is uneven and declining

    Czech Academy of Sciences Publication Activity Database

    Jeschke, J.M.; Aparicio, L.G.; Haider, S.; Heger, T.; Lortie, C. J.; Pyšek, Petr; Strayer, D.L.

    2012-01-01

    Roč. 2012, č. 14 (2012), s. 1-20 ISSN 1619-0033 R&D Projects: GA ČR(CZ) GAP504/11/1028 Institutional support : RVO:67985939 Keywords : biological invasions * hypotheses * testing Subject RIV: EF - Botanics

  7. Testing hypotheses that link wood anatomy to cavitation resistance and hydraulic conductivity in the genus Acer

    NARCIS (Netherlands)

    Lens, F.; Sperry, J.S.; Christmas, M.A.; Rabaey, D.; Jansen, S.

    2011-01-01

    • Vulnerability to cavitation and conductive efficiency depend on xylem anatomy. We tested a large range of structure–function hypotheses, some for the first time, within a single genus to minimize phylogenetic ‘noise’ and maximize detection of functionally relevant variation. • This integrative

  8. Method of Check of Statistical Hypotheses for Revealing of “Fraud” Point of Sale

    Directory of Open Access Journals (Sweden)

    T. M. Bolotskaya

    2011-06-01

    Full Text Available Application method checking of statistical hypotheses fraud Point of Sale working with purchasing cards and suspected of accomplishment of unauthorized operations is analyzed. On the basis of the received results the algorithm is developed, allowing receive an assessment of works of terminals in regime off-line.

  9. Bullying Victimization and Adolescent Self-Harm: Testing Hypotheses from General Strain Theory

    Science.gov (United States)

    Hay, Carter; Meldrum, Ryan

    2010-01-01

    Self-harm is widely recognized as a significant adolescent social problem, and recent research has begun to explore its etiology. Drawing from Agnew's (1992) social psychological strain theory of deviance, this study considers this issue by testing three hypotheses about the effects of traditional and cyber bullying victimization on deliberate…

  10. Why Consumers Choose Managed Mutual Funds over Index Funds: Hypotheses from Consumer Behavior.

    Science.gov (United States)

    Lichtenstein, Donald R.; Kaufmann, Patrick J.; Bhagat, Sanjai

    1999-01-01

    Using the literature of psychology, consumer behavior, and behavioral finance, a series of hypotheses is presented that account for consumer choices of managed over index mutual funds. Results indicate a need for consumer education to increase awareness of the benefits of index investing. (SK)

  11. Utility of Krashen's Five Hypotheses in the Saudi Context of Foreign Language Acquisition/Learning

    Science.gov (United States)

    Gulzar, Malik Ajmal; Gulnaz, Fahmeeda; Ijaz, Attiya

    2014-01-01

    In the last twenty years, the paradigm that has dominated the discipline of language teaching is the SLA theory and Krashen's five hypotheses which are still proving flexible to accommodate earlier reforms. This paper reviews second language acquisition (SLA) theory to establish an understanding of its role in the EFL/ESL classrooms. Other areas…

  12. The Association between Relational Aggression and Perceived Popularity in Early Adolescence: A Test of Competing Hypotheses

    Science.gov (United States)

    Gangel, Meghan J.; Keane, Susan P.; Calkins, Susan D.; Shanahan, Lilly; O'Brien, Marion

    2017-01-01

    This study examined two competing hypotheses regarding the moderators of the association between relational aggression and peer status in early adolescence. The "mitigation relational aggression" hypothesis examined whether positive social behaviors reduced the negative effects of relational aggression, thus amplifying the association…

  13. Distinguishing hypotheses from hyperbole in studies of media violence: A comment on Markey et al

    NARCIS (Netherlands)

    Bushman, B.J.; Romer, D.; Jamieson, P.E.

    2015-01-01

    In alleging that Bushman et al. (2013) made sensational and unsubstantiated claims, Markey et al. (2015) mistake hypotheses for hyperbole. Moreover, in their effort to show that gun violence in PG-13 movies (for ages 13 and older) is unrelated to trends in population violence, they make unjustified

  14. Aggression among Children with ADHD, Anxiety, or Co-Occurring Symptoms: Competing Exacerbation and Attenuation Hypotheses

    Science.gov (United States)

    Becker, Stephen P.; Luebbe, Aaron M.; Stoppelbein, Laura; Greening, Leilani; Fite, Paula J.

    2012-01-01

    Competing hypotheses for explaining the role of anxiety in the relation between attention-deficit/hyperactivity disorder (ADHD) symptoms and childhood aggression were evaluated. Two studies tested whether anxiety exacerbated, attenuated, or had no effect on the relation between ADHD and aggression subtypes among psychiatrically hospitalized…

  15. Cross-Cultural Business Communication Research: State of the Art and Hypotheses for the 1990s.

    Science.gov (United States)

    Limaye, Mohan R.; Victor, David A.

    1991-01-01

    Reviews the scholarly literature in cross-cultural business communication and discusses its shortcomings. Demonstrates the limitations of the Western, linear paradigms and expounds upon some inadequately researched and unresolved important questions. Develops 10 testable hypotheses for the 1990s. Advocates developing new paradigms and concept…

  16. Hypotheses on citation practices as revealed in the literature of the ...

    African Journals Online (AJOL)

    Citations found in two historical articles, which appeared in Cancer Research, a top American Journal, were used to show both positive and negative attitudes towards my 22 historical publications on cancer carriage in the body. Therefore, scientific information concepts are cited critically and two hypotheses are advanced ...

  17. Improving the Development of Student's Research Questions and Hypotheses in an Introductory Business Research Methods Course

    Science.gov (United States)

    Strangman, Lauria; Knowles, Elizabeth

    2012-01-01

    In an introductory research methods course, students often develop research questions and hypotheses that are vague or confusing, do not contain measurable concepts, and are too narrow in scope or vision. Because of this, the final research projects often fail to provide useful information or address the overall research problem. A Lesson Study…

  18. Use of hypotheses for analysis of variance models: challenging the current practice

    NARCIS (Netherlands)

    van Wesel, F.; Boeije, H.R.; Hoijtink, H.

    2013-01-01

    In social science research, hypotheses about group means are commonly tested using analysis of variance. While deemed to be formulated as specifically as possible to test social science theory, they are often defined in general terms. In this article we use two studies to explore the current

  19. Use of hypotheses for analysis of variance Models: Challenging the current practice

    NARCIS (Netherlands)

    van Wesel, F.; Boeije, H.R.; Hoijtink, H

    2013-01-01

    In social science research, hypotheses about group means are commonly tested using analysis of variance. While deemed to be formulated as specifically as possible to test social science theory, they are often defined in general terms. In this article we use two studies to explore the current

  20. Use of hypotheses for analysis of variance models: challenging the current practice.

    NARCIS (Netherlands)

    Wesel, F. van; Boeije, H.; Hoijtink, H.

    2013-01-01

    In social science research, hypotheses about group means are commonly tested using analysis of variance. While deemed to be formulated as specifically as possible to test social science theory, they are often defined in general terms. In this article we use two studies to explore the current

  1. Coping with the Stigma of Mental Illness: Empirically-Grounded Hypotheses from Computer Simulations

    Science.gov (United States)

    Kroska, Amy; Har, Sarah K.

    2011-01-01

    This research demonstrates how affect control theory and its computer program, "Interact", can be used to develop empirically-grounded hypotheses regarding the connection between cultural labels and behaviors. Our demonstration focuses on propositions in the modified labeling theory of mental illness. According to the MLT, negative societal…

  2. Delinquency and Peer Acceptance in Adolescence: A Within-Person Test of Moffitt's Hypotheses

    Science.gov (United States)

    Rulison, Kelly L.; Kreager, Derek A.; Osgood, D. Wayne

    2014-01-01

    We tested 2 hypotheses derived from Moffitt's (1993) taxonomic theory of antisocial behavior, both of which are central to her explanation for the rise in delinquency during adolescence. We tested whether persistently delinquent individuals become more accepted by their peers during adolescence and whether individuals who abstain from delinquent…

  3. Declining forest productivity in aging forest stands: a modeling analysis of alternative hypotheses.

    Science.gov (United States)

    Murty, Danuse; McMurtrie, Ross E.; Ryan, Michael G.

    1996-01-01

    Several explanations have been advanced to account for the decline in forest net primary productivity (NPP) with age in closed-canopy stands including the hypotheses that: (1) sapwood maintenance respiration rate increases, reducing the availability of carbon to support new growth; (2) stomatal conductance and hence photosynthetic efficiency decline; and (3) soil nutrient availability declines. To evaluate these hypotheses we applied the ecosystem model G'DAY to a 40- and a 245-year-old stand of lodgepole pine (Pinus contorta Dougl. ex Loud.), growing on infertile soils. Net primary productivity estimated from biomass data was 0.47 and 0.25 kg C m(-2) year(-1) and foliar nitrogen/carbon ratio (N/C) was 0.0175 and 0.017 for the 40- and 245-year-old stands, respectively. Productivities of the young and old stands were derived from a graphical analysis of the G'DAY model. The graphical analysis also indicated that the observed age-related decline in NPP can be explained in terms of interacting processes associated with Hypotheses 2 and 3. However, the relative importance of these two hypotheses differed depending on key model assumptions, in particular those relating to variation in soil N/C ratio. Thus, if we assumed that soil N/C ratio can vary significantly during stand development, then Hypotheses 2 and 3 jointly explain the decline in NPP, whereas if we assumed that soil N/C ratios are constant, then Hypothesis 3 alone explains the decline in NPP. The analysis revealed that only a small fraction of the decline of NPP can be explained in terms of increasing sapwood respiration.

  4. Congruency sequence effects are driven by previous-trial congruency, not previous-trial response conflict

    OpenAIRE

    Weissman, Daniel H.; Carp, Joshua

    2013-01-01

    Congruency effects in distracter interference tasks are often smaller after incongruent trials than after congruent trials. However, the sources of such congruency sequence effects (CSEs) are controversial. The conflict monitoring model of cognitive control links CSEs to the detection and resolution of response conflict. In contrast, competing theories attribute CSEs to attentional or affective processes that vary with previous-trial congruency (incongruent vs. congruent). The present study s...

  5. NegaWatt 2011-2050 scenario - Hypotheses and method. Technical report, May 2014

    International Nuclear Information System (INIS)

    2014-05-01

    This report proposes an analysis of the negaWatt 2011 scenario. It describes in detail the methodology adopted to elaborate this prospective scenario, and presents the major part of the hypotheses which structure this scenario. A first part presents the approach and methodology (constraints, scenario, model). The second part addresses the issue of energy saving and energy efficiency through a sector-based analysis (housing and office building, transports, industrial and agricultural production). The third part studies the substitution by renewable energies through a supply analysis: energy production based on biomass, renewable energies, and fissile and fossil energies. It outlines the major role of grids in the supply-demand balance. The results of the negaWatt 2011 scenario are presented in terms of final energy, primary energies, and impact on greenhouse gas emissions. Hypotheses and results related to the different sectors (building, transports, industry and agriculture, energy production) are given in appendix

  6. Environmental risk factors (excluding tobacco and microorganisms): critical analysis of old and new hypotheses.

    Science.gov (United States)

    Ekbom, Anders; Montgomery, Scott M

    2004-06-01

    The increase in incidence in both ulcerative colitis and Crohn's disease during the 20th century has led to an abundance of different hypotheses on what sort of exposures are responsible. There has been a special focus on dietary factors, as well as on other exposures introduced on a population-based level, including fast food, cola drinks, toothpaste, antibiotics and oral contraceptives. The aim of this review is to critically assess the results from the different observational studies that have investigated these hypotheses, and also to propose research agendas that should be pursued in the future. The conclusion is that infectious exposures and early bacterial colonization, which are associated with better hygiene early in life and that influence immune function, and possibly oral contraceptives, remain the only exposures of interest for future research into the aetiology of ulcerative colitis and Crohn's disease.

  7. Human ecology in pathogenic landscapes: two hypotheses on how land use change drives viral emergence

    Science.gov (United States)

    Murray, Kris. A.; Daszak, Peter

    2013-01-01

    The emergence of novel viral diseases is driven by socioeconomic, demographic and environmental changes. These include land use changes such as deforestation, agricultural expansion and habitat degradation. However, the links between land use change and disease emergence are poorly understood and likely complex. In this review, we propose two hypotheses for the mechanisms by which land use change can lead to viral emergence: 1) by perturbing disease dynamics in multi-host disease systems via impacts on cross-species transmission rates (the ‘perturbation’ hypothesis); and 2) by allowing exposure of novel hosts to a rich pool of pathogen diversity (the ‘pathogen pool’ hypothesis). We discuss ways that these two hypotheses might be tested using a combination of ecological and virological approaches, and how this may provide novel control and prevention strategies. PMID:23415415

  8. Towards Self-Learning Based Hypotheses Generation in Biomedical Text Domain.

    Science.gov (United States)

    Gopalakrishnan, Vishrawas; Jha, Kishlay; Xun, Guangxu; Ngo, Hung Q; Zhang, Aidong

    2017-12-26

    The overwhelming amount of research articles in the domain of bio-medicine might cause important connections to remain unnoticed. Literature Based Discovery is a sub-field within biomedical text mining that peruses these articles to formulate high confident hypotheses on possible connections between medical concepts. Although many alternate methodologies have been proposed over the last decade, they still suffer from scalability issues. The primary reason, apart from the dense inter-connections between biological concepts, is the absence of information on the factors that lead to the edge-formation. In this work, we formulate this problem as a collaborative filtering task and leverage a relatively new concept of word-vectors to learn and mimic the implicit edge-formation process. Along with single-class classifier, we prune the search-space of redundant and irrelevant hypotheses to increase the efficiency of the system and at the same time maintaining and in some cases even boosting the overall accuracy. We show that our proposed framework is able to prune up to 90% of the hypotheses while still retaining high recall in top-K results. This level of efficiency enables the discovery algorithm to look for higher-order hypotheses, something that was infeasible until now. Furthermore, the generic formulation allows our approach to be agile to performboth open and closed discovery.We also experimentally validate that the core data-structures upon which the system bases its decision has a high concordance with the opinion of the experts.This coupled with the ability to understand the edge formation process provides us with interpretable results without any manual intervention. The relevant JAVA codes are available at: https://github.com/vishrawas/Medline-Code_v2. vishrawa@buffalo.edukishlayj@buffalo.edu. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email

  9. Gender Relations and Economic Development: Hypotheses about the Reversal of Fortune in EurAsia

    OpenAIRE

    de Pleijt, A.M.; van Zanden, J.L.; Carmichael, S.G.

    2016-01-01

    This paper develops an interrelated set of hypotheses about the links between gender relations, family systems and economic development in EurAsia. Firstly, we briefly discuss a number of ideas from the recent literature about the links between gender relations and economic development. Secondly, we suggest a measure of historic gender relations via the classification and measurement of historical family systems, and offer a set of maps of the institutions concerning marriage, inheritance and...

  10. How doctors generate diagnostic hypotheses: a study of radiological diagnosis with functional magnetic resonance imaging.

    Directory of Open Access Journals (Sweden)

    Marcio Melo

    Full Text Available In medical practice, diagnostic hypotheses are often made by physicians in the first moments of contact with patients; sometimes even before they report their symptoms. We propose that generation of diagnostic hypotheses in this context is the result of cognitive processes subserved by brain mechanisms that are similar to those involved in naming objects or concepts in everyday life.To test this proposal we developed an experimental paradigm with functional magnetic resonance imaging (fMRI using radiological diagnosis as a model. Twenty-five radiologists diagnosed lesions in chest X-ray images and named non-medical targets (animals embedded in chest X-ray images while being scanned in a fMRI session. Images were presented for 1.5 seconds; response times (RTs and the ensuing cortical activations were assessed. The mean response time for diagnosing lesions was 1.33 (SD ±0.14 seconds and 1.23 (SD ±0.13 seconds for naming animals. 72% of the radiologists reported cogitating differential diagnoses during trials (3.5 seconds. The overall pattern of cortical activations was remarkably similar for both types of targets. However, within the neural systems shared by both stimuli, activation was significantly greater in left inferior frontal sulcus and posterior cingulate cortex for lesions relative to animals.Generation of diagnostic hypotheses and differential diagnoses made through the immediate visual recognition of clinical signs can be a fast and automatic process. The co-localization of significant brain activation for lesions and animals suggests that generating diagnostic hypotheses for lesions and naming animals are served by the same neuronal systems. Nevertheless, diagnosing lesions was cognitively more demanding and associated with more activation in higher order cortical areas. These results support the hypothesis that medical diagnoses based on prompt visual recognition of clinical signs and naming in everyday life are supported by similar

  11. Statistical analysis of hypotheses on the cointegrating relations in the I(2) model

    DEFF Research Database (Denmark)

    Johansen, Søren

    2006-01-01

    The cointegrated vector autoregressive model for I(2) variables is a non-linear parametric restriction on the linear I(2) regression model for variables of order I(0), I(1) and I(2). In this paper we discuss non-linear submodels given by smooth parametrizations. We give conditions on the parametr......) and the reformulation is applied to show that some hypotheses on the cointegrating coefficients in the cointegrated I(2) model give asymptotic ¿² inference....

  12. Economic and evolutionary hypotheses for cross-population variation in parochialism

    Directory of Open Access Journals (Sweden)

    Daniel Jacob Hruschka

    2013-09-01

    Full Text Available Human populations differ reliably in the degree to which people favor family, friends and community members over strangers and outsiders. In the last decade, researchers have begun to propose several economic and evolutionary hypotheses for these cross-population differences in parochialism. In this paper, we outline major current theories and review recent attempts to test them. We also discuss the key methodological challenges in assessing these diverse economic and evolutionary theories for cross-population differences in parochialism.

  13. Controversial hypotheses on the relationship between researcher and informant in qualitative research.

    Science.gov (United States)

    Wilde, V

    1992-02-01

    This paper addresses methodological issues that emerged unexpectedly during a qualitative study set up to explore nurses' descriptions of difficult, challenging and satisfying experiences at work. The purpose of the study had been to look for critical factors influencing nurses' perceptions of their performance in specific situations, and their labelling of each event. Ten nurses were asked to describe in detail three events; a difficult situation in which they had coped well, a difficult situation in which they would like to have coped better, and a satisfying or rewarding situation. The critical incident technique was used. Rich descriptions were obtained, tape recorded, transcribed verbatum, and analysed by constant comparative analysis, following the principles of grounded theory. Some suprising hypotheses emerged regarding the methodology of the informal interview in qualitative research. This paper addresses these hypotheses, which focus on the interaction between the researcher and informant, the role conflict facing the nurse researcher, the effect of the researcher's past experience on the interaction, the use of counselling strategies and the principle of self-disclosure. These hypotheses were incidental to the original area of study and were more exciting in their emergence because of this.

  14. Validity of the Environmental Kuznets Curve Hypotheses in Water Pollution A Case Study

    Directory of Open Access Journals (Sweden)

    Hediyeh Alishiri

    2017-03-01

    Full Text Available Among the different environmental pollutions, water pollution is of especial importance due to the rather unchanging supply of this vital resource on a global scale and because of the dire consequences of its pollution for human health. The relationship between water production and its pollution can thus established and used as a measure of environmental degradation. This relationship can then be captured and analyzed in terms of environmental Kuznets hypotheses. It may be claimed that the early stages of economic growth is associated with lower per capita income and water pollution but the trend is reversed with increasing per capita income and improved economic growth. The present study was conducted using the panel data technique and the Kuznets environmental hypotheses were examined for the two groups of developed and developing countries under the two scenarios of using either per capita GDP or the share of industry to the added value in GDP as an indicator of economic growth. Results indicate that under both scenarios, Kuznets hypotheses are confirmed when studying the situation in developing countries but refuted in the case of developed countries.

  15. Using climate, energy, and spatial-based hypotheses to interpret macroecological patterns of North America chelonians

    Science.gov (United States)

    Ennen, Joshua R.; Agha, Mickey; Matamoros, Wilfredo A.; Hazzard, Sarah C.; Lovich, Jeffrey E.

    2016-01-01

    Our study investigates how factors, such as latitude, productivity, and several environmental variables, influence contemporary patterns of the species richness in North American turtles. In particular, we test several hypotheses explaining broad-scale species richness patterns on several species richness data sets: (i) total turtles, (ii) freshwater turtles only, (iii) aquatic turtles, (iv) terrestrial turtles only, (v) Emydidae, and (vi) Kinosternidae. In addition to spatial data, we used a combination of 25 abiotic variables in spatial regression models to predict species richness patterns. Our results provide support for multiple hypotheses related to broad-scale patterns of species richness, and in particular, hypotheses related to climate, productivity, water availability, topography, and latitude. In general, species richness patterns were positively associated with temperature, precipitation, diversity of streams, coefficient of variation of elevation, and net primary productivity. We also found that North America turtles follow the general latitudinal diversity gradient pattern (i.e., increasing species richness towards equator) by exhibiting a negative association with latitude. Because of the incongruent results among our six data sets, our study highlights the importance of considering phylogenetic constraints and guilds when interpreting species richness patterns, especially for taxonomic groups that occupy a myriad of habitats.

  16. Stigma models: Testing hypotheses of how images of Nevada are acquired and values are attached to them

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins-Smith, H.C. [New Mexico Univ., Albuquerque, NM (United States)

    1994-12-01

    This report analyzes data from surveys on the effects that images associated with nuclear power and waste (i.e., nuclear images) have on people`s preference to vacation in Nevada. The analysis was stimulated by a model of imagery and stigma which assumes that information about a potentially hazardous facility generates signals that elicit negative images about the place in which it is located. Individuals give these images negative values (valences) that lessen their desire to vacation, relocate, or retire in that place. The model has been used to argue that the proposed Yucca Mountain high-level nuclear waste repository could elicit images of nuclear waste that would stigmatize Nevada and thus impose substantial economic losses there. This report proposes a revised model that assumes that the acquisition and valuation of images depend on individuals` ideological and cultural predispositions and that the ways in which new images will affect their preferences and behavior partly depend on these predispositions. The report tests these hypotheses: (1) individuals with distinct cultural and ideological predispositions have different propensities for acquiring nuclear images, (2) these people attach different valences to these images, (3) the variations in these valences are important, and (4) the valences of the different categories of images within an individual`s image sets for a place correlate very well. The analysis largely confirms these hypotheses, indicating that the stigma model should be revised to (1) consider the relevant ideological and cultural predispositions of the people who will potentially acquire and attach value to the image, (2) specify the kinds of images that previously attracted people to the host state, and (3) consider interactions between the old and potential new images of the place. 37 refs., 18 figs., 17 tabs.

  17. Sub-kilometre (intra-crater) mounds in Utopia Planitia, Mars: character, occurrence and possible formation hypotheses

    Science.gov (United States)

    Soare, Richard J.; Conway, Susan J.; Pearce, Geoffrey D.; Costard, François; Séjourné, Antoine

    2013-08-01

    At the middle latitudes of Utopia Planitia (˜35-45°N; ˜65-101°E) hundreds of small-sized mounds located in sub-kilometre impact craters dot the landscape. Their shape varies from circular to crescentic and their height ranges from ˜10 to 50 m. Often, metre to decametre pitting is observed, as is metres-thick banding or stratification. Mound albedo is relatively high, i.e. ˜0.16. The plain's terrain in the region, previously linked to the latitude-dependent mantle (LDM) of ice-dust, displays pitting and albedo similar to the small intra-crater mounds. Some workers have suggested that the mounds and the plain's terrain share a common ice-dust origin. If so, then scrutinising the mounds could provide analogical insight on the key geological characteristics and spatial distribution of the LDM itself. Other workers have hypothesised that the mounds are eroded sedimentary landforms or periglacial mounds underlain by a perennial ice-core (closed-system pingos). In this article we develop and then discuss each of the three mound-hypotheses in a much more substantial manner than has been done hitherto. Towards this end we use high-resolution images, present a detailed regional-map of mound distribution and establish a regional platform of topographical analysis using MOLA data superposed on a large-scale CTX mosaic. Although the ice-dust hypothesis is consistent with some observations and measurements, we find that a (loess-based) sedimentary hypothesis shows greater plausibility. Of the three hypotheses evaluated, the pingo or periglacial one is the weakest.

  18. Stigma models: Testing hypotheses of how images of Nevada are acquired and values are attached to them

    International Nuclear Information System (INIS)

    Jenkins-Smith, H.C.

    1994-12-01

    This report analyzes data from surveys on the effects that images associated with nuclear power and waste (i.e., nuclear images) have on people's preference to vacation in Nevada. The analysis was stimulated by a model of imagery and stigma which assumes that information about a potentially hazardous facility generates signals that elicit negative images about the place in which it is located. Individuals give these images negative values (valences) that lessen their desire to vacation, relocate, or retire in that place. The model has been used to argue that the proposed Yucca Mountain high-level nuclear waste repository could elicit images of nuclear waste that would stigmatize Nevada and thus impose substantial economic losses there. This report proposes a revised model that assumes that the acquisition and valuation of images depend on individuals' ideological and cultural predispositions and that the ways in which new images will affect their preferences and behavior partly depend on these predispositions. The report tests these hypotheses: (1) individuals with distinct cultural and ideological predispositions have different propensities for acquiring nuclear images, (2) these people attach different valences to these images, (3) the variations in these valences are important, and (4) the valences of the different categories of images within an individual's image sets for a place correlate very well. The analysis largely confirms these hypotheses, indicating that the stigma model should be revised to (1) consider the relevant ideological and cultural predispositions of the people who will potentially acquire and attach value to the image, (2) specify the kinds of images that previously attracted people to the host state, and (3) consider interactions between the old and potential new images of the place. 37 refs., 18 figs., 17 tabs

  19. Vicariance and Oceanic Barriers Drive Contemporary Genetic Structure of Widespread Mangrove Species Sonneratia alba J. Sm in the Indo-West Pacific

    Directory of Open Access Journals (Sweden)

    Alison K. S. Wee

    2017-12-01

    Full Text Available Patterns of genetic structure are essential for a comprehensive understanding of the evolution and biogeography of a species. Here, we investigated the genetic patterns of one of the most widespread and abundant mangrove species in the Indo-West Pacific, Sonneratia alba J. Sm., in order to gain insights into the ecological and evolutionary drivers of genetic structure in mangroves. We employed 11 nuclear microsatellite loci and two chloroplast regions to genotyped 25 S. alba populations. Our objectives were to (1 assess the level of genetic diversity and its geographic distribution; and (2 determine the genetic structure of the populations. Our results revealed significant genetic differentiation among populations. We detected a major genetic break between Indo-Malesia and Australasia, and further population subdivision within each oceanic region in these two major clusters. The phylogeographic patterns indicated a strong influence of vicariance, oceanic barriers and geographic distance on genetic structure. In addition, we found low genetic diversity and high genetic drift at range edge. This study advances the scope of mangrove biogeography by demonstrating a unique scenario whereby a widespread species has limited dispersal and high genetic divergence among populations.

  20. Did vicariance and adaptation drive cryptic speciation and evolution of brooding in Ophioderma longicauda (Echinodermata: Ophiuroidea), a common Atlanto-Mediterranean ophiuroid?

    Science.gov (United States)

    Boissin, E; Stöhr, S; Chenuil, A

    2011-11-01

    Over the last decade, cryptic speciation has been discovered in an increasing number of taxa. Species complexes are useful models for the understanding of speciation processes. Motivated by the discovery of brooding specimens in the common Atlanto-Mediterranean broadcast spawning brittle star, Ophioderma longicauda, a recent study revealed the occurrence of divergent mitochondrial lineages. We analysed 218 specimens from 23 locations spread over the geographic range of the species with partial Cytochrome c Oxidase subunit I (COI) sequences. A subset of this sample was also surveyed with the internal transcribed spacer of the ribosomal DNA cluster (nuclear ITS-1). Our study revealed six highly divergent mitochondrial lineages, and the ITS-1 data confirmed that they most likely represent a species complex. Geographic ranges, abundances and genetic structures are contrasted among the putative cryptic species. Lineages in which brooding specimens have been found form a monophyletic group and are restricted to the Eastern Mediterranean basin, an oligotrophic zone. A phylogeny-trait association analysis revealed a phylogenetic signal for low 'chlorophyll a' values (our proxy for oligotrophy). An ecological shift related to the hyper oligotrophy of the Eastern Mediterranean region is therefore likely to have played a role in the evolution of brooding. This study revealed that a complex mixture of vicariance, population expansion, adaptive divergence and possibly high local diversification rates resulting from brooding has shaped the evolution of this species complex. The dating analysis showed that these events probably occurred in the Pleistocene epoch. © 2011 Blackwell Publishing Ltd.

  1. Investigating the effect of previous treatments on wheat biomass over multiple spatial frequencies

    Science.gov (United States)

    Milne, A. E.; Castellanos, M. T.; Cartagena, M. C.; Tarquis, A. M.; Lark, R. M.

    2010-09-01

    In this study we use the maximum overlap discrete packet transform (MODWPT) to investigate residual effects on wheat biomass of fertigation treatments applied to a previous crop. The wheat crop covered nine subplots from a previous experiment on melon response to fertigation. Each subplot had previously received a different level of applied nitrogen. Many factors affect wheat biomass, causing it to vary at different spatial frequencies. We hypothesize that these will include residual effects from fertilizer application (at relatively low spatial frequencies) and the local influence of individual plants from the previous melon crop (at high frequency). To test this hypothesis we use the MODWPT to identify the dominant spatial frequencies of wheat biomass variation, and analyse the relationship to both the previous fertilizer application and the location of individual melon plants in the previous crop. The MODWPT is particularly appropriate for this because it allows us first to identify the key spatial frequencies in the wheat biomass objectively and to analyse them, and their relationship to hypothesized driving factors without any assumptions of uniformity (stationarity) of wheat-biomass variation. The results showed that the applied nitrogen dominated the wheat biomass response, and that there was a noticeable component of wheat-biomass variation at the spatial frequency that corresponds to the melon cropping. We expected wheat biomass to be negatively correlated with the position of melons in the previous crop, due to uptake of the applied nitrogen. The MODWPT, which allows us to detect changes in correlation between variables at different frequencies, showed that such a relationship was found across part of the experiment but not uniformly.

  2. Testing hypotheses of velocity and celerity at the catchment scale using ensemble hydrograph separation

    Science.gov (United States)

    Kirchner, James

    2017-04-01

    Making hydrological models more realistic requires both better physical understanding of their underlying processes, and more rigorous tests of the hypotheses that they embody. In the current model-testing paradigm, multiple interdependent hypotheses are combined to generate model predictions, which are then compared with observational time series that reflect multiple interdependent forcings. This approach is problematic in several respects. If the modeled time series does not match the observations, which of the model's many embedded hypotheses is falsified? Conversely, even if the model matches the data, how many of its underlying hypotheses could still be wrong, perhaps in offsetting ways? The essence of the problem is that if model simulations depend on many interacting hypotheses, and if observational data reflect many different environmental forcings, then comparisons of simulations against data will rarely be diagnostic tests of specific hypotheses in the model. For this reason, I have long argued for a different approach to hypothesis testing, in which key signatures of behavior are extracted from both model and data before they are compared (Kirchner et al., 1996; Kirchner, 2006). This approach allows one to isolate the model/data comparison as much as possible from potentially confounding factors in both the model and the data. One key signature of catchment behavior, which has challenged many hydrologic models, is the contrast between the relatively short timescales of hydrologic response to precipitation events, reflecting the celerity of hydraulic potentials, and the much longer timescales of water transport through the landscape, reflecting the velocity of water movement as tracked by passive tracers (Kirchner, 2003). Here I show how both the velocity and celerity of transport at the catchment scale can be quantified from hydrologic and isotopic time series. The conventional formula used for hydrograph separation can be converted into an equivalent

  3. Intramedullary cervical spinal cord abscess by viridans group Streptococcus secondary to infective endocarditis and facilitated by previous local radiotherapy.

    Science.gov (United States)

    Fernández-Ruiz, Mario; López-Medrano, Francisco; García-Montero, María; Hornedo-Muguiro, Javier; Aguado, Jose-María

    2009-01-01

    The risk factors, microbial patterns, and prognosis of intramedullary abscess have varied with time. The development of an intramedullary abscess of the spinal cord (IASC) constitutes an exceptional complication of infective endocarditis (IE) in the post-antibiotic era. We present a case of cervical IASC by viridans group Streptococcus in a patient with mitral valve IE. We hypothesize that previous cervical radiotherapy for non-Hodgkin's lymphoma favoured the occurrence of this uncommon entity. This physiopathologic mechanism has not been previously reported.

  4. Pickles and Ice Cream! Food Cravings in Pregnancy: Hypotheses, Preliminary Evidence, and Directions for Future Research

    Directory of Open Access Journals (Sweden)

    Natalia C. Orloff

    2014-09-01

    Full Text Available Women in the United States experience an increase in food cravings at two specific times during their life, 1 perimenstrually and 2 prenatally. The prevalence of excess gestational weight gain (GWG is a growing concern due to its association with adverse health outcomes in both mothers and children. To the extent that prenatal food cravings may be a determinant of energy intake in pregnancy, a better understanding of craving etiology could be crucial in addressing the issue of excessive GWG. This paper reviews the available literature to corroborate and/or dispute some of the most commonly accepted hypotheses regarding the causes of food cravings during pregnancy, including a role of 1 hormonal changes, 2 nutritional deficits, 3 pharmacologically active ingredients in the desired foods, and 4 cultural and psychosocial factors. An existing model of perimenstrual chocolate craving etiology serves to structure the discussion of these hypotheses. The main hypotheses discussed receive little support, with the notable exception of a postulated role of cultural and psychosocial factors. The presence of cravings during pregnancy is a common phenomenon across different cultures, but the types of foods desired and the adverse impact of cravings on health may be culture-specific. Various psychosocial factors appear to correlate with excess GWG, including the presence of restrained eating. Findings strongly suggest that more research be conducted in this area. We propose that future investigations fall into one of the four following categories: 1 validation of food craving and eating-related measures specifically in pregnant populations, 2 use of ecological momentary assessment to obtain real time data on cravings during pregnancy, 3 implementation of longitudinal studies to address causality between eating disorder symptoms, food cravings, and gestational weight gain, and 4 development of interventions to ensure proper prenatal nutrition and prevent excess

  5. Evaluating Hypotheses of Plant Species Invasions on Mediterranean Islands: Inverse Patterns between Alien and Endemic Species

    Directory of Open Access Journals (Sweden)

    Alexander Bjarnason

    2017-08-01

    Full Text Available Invasive alien species cause major changes to ecosystem functioning and patterns of biodiversity, and the main factors involved in invasion success remain contested. Using the Mediterranean island of Crete, Greece as a case study, we suggest a framework for analyzing spatial data of alien species distributions, based on environmental predictors, aiming to gain an understanding of their spatial patterns and spread. Mediterranean islands are under strong ecological pressure from invading species due to their restricted size and increased human impact. Four hypotheses of invasibility, the “propagule pressure hypothesis” (H1, “biotic resistance hypothesis vs. acceptance hypothesis” (H2, “disturbance-mediated hypothesis” (H3, and “environmental heterogeneity hypothesis” (H4 were tested. Using data from alien, native, and endemic vascular plant species, the propagule pressure, biotic resistance vs. acceptance, disturbance-mediated, and environmental heterogeneity hypotheses were tested with Generalized Additive Modeling (GAM of 39 models. Based on model selection, the optimal model includes the positive covariates of native species richness, the negative covariates of endemic species richness, and land area. Variance partitioning between the four hypotheses indicated that the biotic resistance vs. acceptance hypothesis explained the vast majority of the total variance. These results show that areas of high species richness have greater invasibility and support the acceptance hypothesis and “rich-get-richer” distribution of alien species. The negative correlation between alien and endemic species appears to be predominantly driven by altitude, with fewer alien and more endemic species at greater altitudes, and habitat richness. The negative relationship between alien and endemic species richness provides potential for understanding patterns of endemic and alien species on islands, contributing to more effective conservation

  6. Soy-Based Therapeutic Baby Formulas: Testable Hypotheses Regarding the Pros and Cons.

    Science.gov (United States)

    Westmark, Cara J

    2016-01-01

    Soy-based infant formulas have been consumed in the United States since 1909, and currently constitute a significant portion of the infant formula market. There are efforts underway to generate genetically modified soybeans that produce therapeutic agents of interest with the intent to deliver those agents in a soy-based infant formula platform. The threefold purpose of this review article is to first discuss the pros and cons of soy-based infant formulas, then present testable hypotheses to discern the suitability of a soy platform for drug delivery in babies, and finally start a discussion to inform public policy on this important area of infant nutrition.

  7. H-convergence for quasi-linear elliptic equations under natural hypotheses on the correctors

    International Nuclear Information System (INIS)

    Bensoussan, A.; Boccardo, L.; Dall'Aglio, A.; Murat, F.

    1995-01-01

    In this paper we study the behavior of the solutions of quasi-linear Dirichlet problems when the principal parts H-converge and when the lower order terms have quadratic growth with respect to the gradient. We show that the limit problem consists of a principal part which is the H-limit of the principal parts and of the lower order term which is constructed from the corresponding terms by using a linear corrector result. We assume only natural hypotheses on the correctors (i.e. L 2 equi-integrability and not L ∞ boundedness). (author)

  8. Hypotheses regarding the mechanisms of ayahuasca in the treatment of addictions.

    Science.gov (United States)

    Liester, Mitchell B; Prickett, James I

    2012-01-01

    Ayahuasca is a medicinal plant mixture utilized by indigenous peoples throughout the Amazon River basin for healing purposes. The "vine of the soul" or "vine of death," as it is known in South America, contains a combination of monoamine oxidase inhibitors and N,N-dimethyltryptamine (DMT). When ingested together, these medicines produce profound alterations in consciousness. Increasingly, ayahuasca is being utilized to treat addictions. However, the mechanism of action by which ayahuasca treats addictions remains unclear. We offer four hypotheses to explain possible biochemical, physiological, psychological, and transcendent mechanisms by which ayahuasca may exert its anti-addiction effects.

  9. PreBötzinger complex and pacemaker neurons: hypothesized site and kernel for respiratory rhythm generation

    DEFF Research Database (Denmark)

    Rekling, J C; Feldman, J L

    1998-01-01

    Identification of the sites and mechanisms underlying the generation of respiratory rhythm is of longstanding interest to physiologists and neurobiologists. Recently, with the development of novel experimental preparations, especially in vitro en bloc and slice preparations of rodent brainstem......, progress has been made In particular, a site in the ventrolateral medulla, the preBötzinger Complex, is hypothesized to contain neuronal circuits generating respiratory rhythm. Lesions or disruption of synaptic transmission within the preBötzinger Complex, either in vivo or in vitro, can abolish...

  10. New evidence about language and cognitive development based on a longitudinal study: hypotheses for intervention.

    Science.gov (United States)

    Goldin-Meadow, Susan; Levine, Susan C; Hedges, Larry V; Huttenlocher, Janellen; Raudenbush, Stephen W; Small, Steven L

    2014-09-01

    We review findings from a four-year longitudinal study of language learning conducted on two samples: a sample of typically developing children whose parents vary substantially in socioeconomic status, and a sample of children with pre- or perinatal brain injury. This design enables us to study language development across a wide range of language learning environments and a wide range of language learners. We videotaped samples of children's and parents' speech and gestures during spontaneous interactions at home every four months, and then we transcribed and coded the tapes. We focused on two behaviors known to vary across individuals and environments-child gesture and parent speech-behaviors that have the potential to index, and perhaps even play a role in creating, differences across children in linguistic and other cognitive skills. Our observations have led to four hypotheses that have promise for the development of diagnostic tools and interventions to enhance language and cognitive development and brain plasticity after neonatal injury. One kind of hypothesis involves tools that could identify children who may be at risk for later language deficits. The other involves interventions that have the potential to promote language development. We present our four hypotheses as a summary of the findings from our study because there is scientific evidence behind them and because this evidence has the potential to be put to practical use in improving education. (c) 2014 APA, all rights reserved.

  11. New Evidence About Language and Cognitive Development Based on a Longitudinal Study: Hypotheses for Intervention

    Science.gov (United States)

    Goldin-Meadow, Susan; Levine, Susan C.; Hedges, Larry V.; Huttenlocher, Janellen; Raudenbush, Stephen W.; Small, Steven L.

    2014-01-01

    We review findings from a four-year longitudinal study of language learning conducted on two samples: a sample of typically developing children whose parents vary substantially in socioeconomic status, and a sample of children with pre- or perinatal brain injury. This design enables us to study language development across a wide range of language learning environments and a wide range of language learners. We videotaped samples of children's and parents' speech and gestures during spontaneous interactions at home every four months, and then we transcribed and coded the tapes. We focused on two behaviors known to vary across individuals and environments—child gesture and parent speech—behaviors that have the potential to index, and perhaps even play a role in creating, differences across children in linguistic and other cognitive skills. Our observations have led to four hypotheses that have promise for the development of diagnostic tools and interventions to enhance language and cognitive development and brain plasticity after neonatal injury. One kind of hypothesis involves tools that could identify children who may be at risk for later language deficits. The other involves interventions that have the potential to promote language development. We present our four hypotheses as a summary of the findings from our study because there is scientific evidence behind them and because this evidence has the potential to be put to practical use in improving education. PMID:24911049

  12. Hypothesized, Directly-Coded Curve Shapes in Growth Curve Analysis: An Example

    Directory of Open Access Journals (Sweden)

    Patricia M. Herman

    2013-02-01

    Full Text Available Growth curve analysis provides important informational benefits regarding intervention outcomes over time. Rarely, however, should outcome trajectories be assumed to be linear. Instead, both the shape and the slope of the growth curve can be estimated. Non-linear growth curves are usually modeled by including either higher-order time variables or orthogonal polynomial contrast codes. Each has limitations (multicollinearity with the first, a lack of coefficient interpretability with the second, and a loss of degrees of freedom with both and neither encourages direct testing of alternative hypothesized curve shapes. Especially in studies with relatively small samples it is likely to be useful to preserve as much information as possible at the individual level. This article presents a step-by-step example of the use and testing of hypothesized curve shapes in the estimation of growth curves using hierarchical linear modeling for a small intervention study. DOI: 10.2458/azu_jmmss.v3i2.16476

  13. Race-Ethnicity and Health Trajectories: Tests of Three Hypotheses across Multiple Groups and Health Outcomes

    Science.gov (United States)

    Brown, Tyson H.; O’Rand, Angela M.; Adkins, Daniel E.

    2013-01-01

    Racial-ethnic disparities in static levels of health are well documented. Less is known about racial-ethnic differences in age trajectories of health. The few studies on this topic have examined only single health outcomes and focused on black-white disparities. This study extends prior research by using a life course perspective, panel data from the Health and Retirement Study, and multilevel growth curve models to investigate racial-ethnic differences in the trajectories of serious conditions and functional limitations among blacks, Mexican Americans, and whites. We test three hypotheses on the nature of racial-ethnic disparities in health across the life course (aging-as-leveler, persistent inequality, and cumulative disadvantage). Results controlling for mortality selection reveal that support for the hypotheses varies by health outcome, racial-ethnic group, and life stage. Controlling for childhood socioeconomic status, adult social and economic resources, and health behaviors reduces but does not eliminate racial-ethnic disparities in health trajectories. PMID:22940814

  14. The evolution of parental care in insects: A test of current hypotheses

    Science.gov (United States)

    Gilbert, James D J; Manica, Andrea

    2015-01-01

    Which sex should care for offspring is a fundamental question in evolution. Invertebrates, and insects in particular, show some of the most diverse kinds of parental care of all animals, but to date there has been no broad comparative study of the evolution of parental care in this group. Here, we test existing hypotheses of insect parental care evolution using a literature-compiled phylogeny of over 2000 species. To address substantial uncertainty in the insect phylogeny, we use a brute force approach based on multiple random resolutions of uncertain nodes. The main transitions were between no care (the probable ancestral state) and female care. Male care evolved exclusively from no care, supporting models where mating opportunity costs for caring males are reduced—for example, by caring for multiple broods—but rejecting the “enhanced fecundity” hypothesis that male care is favored because it allows females to avoid care costs. Biparental care largely arose by males joining caring females, and was more labile in Holometabola than in Hemimetabola. Insect care evolution most closely resembled amphibian care in general trajectory. Integrating these findings with the wealth of life history and ecological data in insects will allow testing of a rich vein of existing hypotheses. PMID:25825047

  15. Confidence Intervals: From tests of statistical significance to confidence intervals, range hypotheses and substantial effects

    Directory of Open Access Journals (Sweden)

    Dominic Beaulieu-Prévost

    2006-03-01

    Full Text Available For the last 50 years of research in quantitative social sciences, the empirical evaluation of scientific hypotheses has been based on the rejection or not of the null hypothesis. However, more than 300 articles demonstrated that this method was problematic. In summary, null hypothesis testing (NHT is unfalsifiable, its results depend directly on sample size and the null hypothesis is both improbable and not plausible. Consequently, alternatives to NHT such as confidence intervals (CI and measures of effect size are starting to be used in scientific publications. The purpose of this article is, first, to provide the conceptual tools necessary to implement an approach based on confidence intervals, and second, to briefly demonstrate why such an approach is an interesting alternative to an approach based on NHT. As demonstrated in the article, the proposed CI approach avoids most problems related to a NHT approach and can often improve the scientific and contextual relevance of the statistical interpretations by testing range hypotheses instead of a point hypothesis and by defining the minimal value of a substantial effect. The main advantage of such a CI approach is that it replaces the notion of statistical power by an easily interpretable three-value logic (probable presence of a substantial effect, probable absence of a substantial effect and probabilistic undetermination. The demonstration includes a complete example.

  16. A multilocus evaluation of ermine (Mustela erminea) across the Holarctic, testing hypotheses of Pleistocene diversification in response to climate change

    Science.gov (United States)

    Dawson, Natalie G.; Hope, Andrew G.; Talbot, Sandra L.; Cook, Joseph A.

    2013-01-01

    Aim: We examined data for ermine (Mustela erminea) to test two sets of diversification hypotheses concerning the number and location of late Pleistocene refugia, the timing and mode of diversification, and the evolutionary influence of insularization. Location: Temperate and sub-Arctic Northern Hemisphere. Methods: We used up to two mitochondrial and four nuclear loci from 237 specimens for statistical phylogeographical and demographic analyses. Coalescent species-tree estimation used a Bayesian approach for clade divergence based on external mutation rate calibrations. Approximate Bayesian methods were used to assess population size, timing of divergence and gene flow. Results: Limited structure coupled with evidence of population growth across broad regions, including previously ice-covered areas, indicated expansion from multiple centres of differentiation, but high endemism along the North Pacific coast (NPC). A bifurcating model of diversification with recent growth spanning three glacial cycles best explained the empirical data. Main conclusions: A newly identified clade in North America indicated a fourth refugial area for ermine. The shallow coalescence of all extant ermine reflects a recent history of diversification overlying a deeper fossil record. Post-glacial colonization has led to potential contact zones for multiple lineages in north-western North America. A model of diversification of ermine accompanied by recent gene flow was marginally less well supported than a model of divergence of major clades in response to the most recent glacial cycles.

  17. Phylogeographical structure of the neotropical forest tree Hymenaea courbaril (Leguminosae: Caesalpinioideae) and its relationship with the Vicariant Hymenaea stigonocarpa from Cerrado.

    Science.gov (United States)

    Ramos, Ana Carolina Simões; De Lemos-Filho, José Pires; Lovato, Maria Bernadete

    2009-01-01

    The phylogeography of Hymenaea courbaril var. stilbocarpa from Atlantic Forest and riverine forests of the Cerrado biome in central and southeastern Brazil was investigated. The data were compared with those of its congeneric Hymenaea stigonocarpa, a typical tree from savanna. In the Cerrado, H. courbaril var. stilbocarpa is found in sites contiguous with those of H. stigonocarpa, and they share common life-history attributes. The psbC/trnS3 region of the chloroplast DNA was sequenced in 149 individuals of H. courbaril var. stilbocarpa. High genetic variation was found in this species, with the identification of 18 haplotypes, similarly to what was found in H. stigonocarpa with 23 haplotypes in the same geographic region. Populations of H. courbaril var. stilbocarpa could be structured in 3 phylogeographic groups. Spatial analysis of molecular variation indicated that 46.4% of the genetic variation was due to differences among these groups. Three haplotypes were shared by H. courbaril var. stilbocarpa and H. stigonocarpa, and only 10.5% of the total genetic variation could be attributed to between-species difference. We surmise that during the glacial times, H. courbaril var. stilbocarpa populations must have gone extinct in most parts of the southern of its present-day occurrence area. After climate amelioration, these areas were probably recolonized from northern and eastern. The relatively similar phylogeographic structure of vicariant Hymenaea species suggests that they were subjected to the same impacts during the Quaternary climatic fluctuations. The sharing of haplotypes and the genetic similarity between the 2 Hymenaea species suggest the existence of ancestral polymorphism and/or hybridization.

  18. A robotic approach to understanding the role and the mechanism of vicarious trial-and-error in a T-maze task.

    Directory of Open Access Journals (Sweden)

    Eiko Matsuda

    Full Text Available Vicarious trial-and-error (VTE is a behavior observed in rat experiments that seems to suggest self-conflict. This behavior is seen mainly when the rats are uncertain about making a decision. The presence of VTE is regarded as an indicator of a deliberative decision-making process, that is, searching, predicting, and evaluating outcomes. This process is slower than automated decision-making processes, such as reflex or habituation, but it allows for flexible and ongoing control of behavior. In this study, we propose for the first time a robotic model of VTE to see if VTE can emerge just from a body-environment interaction and to show the underlying mechanism responsible for the observation of VTE and the advantages provided by it. We tried several robots with different parameters, and we have found that they showed three different types of VTE: high numbers of VTE at the beginning of learning, decreasing numbers afterward (similar VTE pattern to experiments with rats, low during the whole learning period, and high numbers all the time. Therefore, we were able to reproduce the phenomenon of VTE in a model robot using only a simple dynamical neural network with Hebbian learning, which suggests that VTE is an emergent property of a plastic and embodied neural network. From a comparison of the three types of VTE, we demonstrated that 1 VTE is associated with chaotic activity of neurons in our model and 2 VTE-showing robots were robust to environmental perturbations. We suggest that the instability of neuronal activity found in VTE allows ongoing learning to rebuild its strategy continuously, which creates robust behavior. Based on these results, we suggest that VTE is caused by a similar mechanism in biology and leads to robust decision making in an analogous way.

  19. A robotic approach to understanding the role and the mechanism of vicarious trial-and-error in a T-maze task.

    Science.gov (United States)

    Matsuda, Eiko; Hubert, Julien; Ikegami, Takashi

    2014-01-01

    Vicarious trial-and-error (VTE) is a behavior observed in rat experiments that seems to suggest self-conflict. This behavior is seen mainly when the rats are uncertain about making a decision. The presence of VTE is regarded as an indicator of a deliberative decision-making process, that is, searching, predicting, and evaluating outcomes. This process is slower than automated decision-making processes, such as reflex or habituation, but it allows for flexible and ongoing control of behavior. In this study, we propose for the first time a robotic model of VTE to see if VTE can emerge just from a body-environment interaction and to show the underlying mechanism responsible for the observation of VTE and the advantages provided by it. We tried several robots with different parameters, and we have found that they showed three different types of VTE: high numbers of VTE at the beginning of learning, decreasing numbers afterward (similar VTE pattern to experiments with rats), low during the whole learning period, and high numbers all the time. Therefore, we were able to reproduce the phenomenon of VTE in a model robot using only a simple dynamical neural network with Hebbian learning, which suggests that VTE is an emergent property of a plastic and embodied neural network. From a comparison of the three types of VTE, we demonstrated that 1) VTE is associated with chaotic activity of neurons in our model and 2) VTE-showing robots were robust to environmental perturbations. We suggest that the instability of neuronal activity found in VTE allows ongoing learning to rebuild its strategy continuously, which creates robust behavior. Based on these results, we suggest that VTE is caused by a similar mechanism in biology and leads to robust decision making in an analogous way.

  20. Attribution of hydrological change using the Method of Multiple Working Hypotheses

    Science.gov (United States)

    Harrigan, Shaun

    2017-04-01

    The methods we have developed for managing our long-term water supply and protection from extreme hydrological events such as droughts and floods have been founded on the assumption that the hydrological cycle operates under natural conditions. However, it increasingly recognised that humans have the potential to induce significant change in almost every component of the hydrological cycle, for example, climate change, land-use change, and river engineering. Statistical detection of change in streamflow, outside that of natural variability, is an important scientific endeavour, but it does not tell us anything about the drivers of change. Attribution is the process of establishing the most likely cause(s) of a detected change - the why. Attribution is complex due to the integrated nature of streamflow and the proliferation of multiple possible drivers. It is perhaps this complexity, combined with few proven theoretical approaches to this problem in hydrology that has led to others to call for "more efforts and scientific rigour" (Merz et al., 2012). It is easier to limit the cause of a detected change to a single driver, or use simple correlation analysis alone as evidence of causation. It is convenient when the direction of a change in streamflow is consistent with what is expected from a well-known driver such as climate change. Over a century ago, Thomas Chamberlin argued these types of issues were common in many disciplines given how the scientific method is approached in general. His 1890 article introduces the Method of Multiple Working Hypotheses (MMWH) in an attempt to limit our confirmation bias and strives for increased objectivity. This presentation will argue that the MMWH offers an attractive theoretical approach to the attribution of hydrological change in modern hydrology as demonstrated through a case study of a well-documented change point in streamflow within the Boyne Catchment in Ireland. Further Reading Chamberlin, T. C.: The Method of Multiple

  1. Treating fossils as terminal taxa in divergence time estimation reveals ancient vicariance patterns in the palpimanoid spiders

    DEFF Research Database (Denmark)

    Wood, Hannah Marie; Matzke, Nicholas J.; Gillespie, Rosemary G.

    2013-01-01

    Incorporation of fossils into biogeographic studies can have a profound effect on the conclusions that result, particularly when fossil ranges are nonoverlapping with extant ranges. This is the case in archaeid spiders, where there are known fossils from the Northern Hemisphere, yet all living...... the archaeid fossil taxa as both node calibrations and as noncontemporaneous terminal tips, both with and without additional calibration points. Estimation of ancestral biogeographic ranges is then performed, using likelihood and Bayesian methods to take into account uncertainty in phylogeny and in dating. We...... find that treating the fossils as terminal tips within a Bayesian framework, as opposed to dating the phylogeny based only on molecular data with the dates coming from node calibrations, removes the subjectivity involved in assigning priors, which has not been possible with previous methods. Our...

  2. Development of working hypotheses linking management of the Missouri River to population dynamics of Scaphirhynchus albus (pallid sturgeon)

    Science.gov (United States)

    Jacobson, Robert B.; Parsley, Michael J.; Annis, Mandy L.; Colvin, Michael E.; Welker, Timothy L.; James, Daniel A.

    2016-01-20

    This report documents a process of filtering of hypotheses that relate Missouri River Scaphirhynchus albus (pallid sturgeon) population dynamics to management actions including flow alterations, channel reconfigurations, and pallid sturgeon population augmentation. The filtering process was a partnership among U.S. Geological Survey, U.S. Army Corps of Engineers, and U.S. Fish and Wildlife Service to contribute to the Missouri River Recovery Management Plan process. The objective of the filtering process was to produce a set of hypotheses with high relevance to pallid sturgeon population dynamics and decision making on the Missouri River. The Missouri River Pallid Sturgeon Effects Analysis team filtered hundreds of potential hypotheses implicit in conceptual ecological models to develop a set of 40 candidate dominant hypotheses that were identified by experts as being important in pallid sturgeon population dynamics. Using a modified Delphi process and additional expert opinion, the team reduced this set of hypotheses to 23 working dominant hypotheses. We then matched the 23 hypotheses with management actions that could influence the biotic outcomes, resulting in as many as 176 potential effects between management actions and pallid sturgeon in the Missouri River. This number was consolidated to a candidate set of 53 working management hypotheses because some management actions applied to multiple life stages of the pallid sturgeon. We used an additional round of expert surveys to identify a set of 30 working management hypotheses. Finally, the set of working management hypotheses was filtered by the U.S. Army Corps of Engineers, Missouri River Recovery Program for actions that were within the agency’s authority and jurisdiction. This round resulted in a set of 21 hypotheses for initial modeling of linkages from management to pallid sturgeon population responses.

  3. Science from evaluation: testing hypotheses about differential effects of three youth-focused suicide prevention trainings.

    Science.gov (United States)

    Coleman, Daniel; Del Quest, Aisling

    2015-01-01

    As part of an evaluation component of a youth suicide prevention, a quasi-experimental repeated measures design tested hypotheses about two brief suicide prevention gatekeeper trainings (Question, Persuade, Refer [QPR] and RESPONSE) and one longer suicide intervention skills training (Applied Suicide Intervention Skills Training [ASIST]). All three trainings showed large changes in prevention attitudes and self-efficacy, largely maintained at follow-up. ASIST trainees had large increases in asking at-risk youth about suicide at follow-up. Convergent with other research, modeling and role-play in training are crucial to increased prevention behaviors. Practice and research implications are discussed, including social work roles in suicide prevention and research.

  4. Combining soft decision algorithms and scale-sequential hypotheses pruning for object recognition

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, V.P.; Manolakos, E.S. [Northeastern Univ., Boston, MA (United States)

    1996-12-31

    This paper describes a system that exploits the synergy of Hierarchical Mixture Density (HMD) estimation with multiresolution decomposition based hypothesis pruning to perform efficiently joint segmentation and labeling of partially occluded objects in images. First we present the overall structure of the HMD estimation algorithm in the form of a recurrent neural network which generates the posterior probabilities of the various hypotheses associated with the image. Then in order to reduce the large memory and computation requirement we propose a hypothesis pruning scheme making use of the orthonormal discrete wavelet transform for dimensionality reduction. We provide an intuitive justification for the validity of this scheme and present experimental results and performance analysis on real and synthetic images to verify our claims.

  5. Factors that encourage females to pursue physical science careers: Testing five common hypotheses

    Science.gov (United States)

    Hazari, Zahra; Potvin, Geoff; Lock, Robynne M.; Lung, Florin; Sadler, Philip M.; Sonnert, Gerhard

    2012-03-01

    There are many hypotheses regarding factors that may encourage female students to pursue careers in the physical sciences. Using Propensity Score Matching (PSM) on national data (n=7505) drawn from the Persistence Research in Science and Engineering (PRiSE) project, we test five commonly held beliefs including having a single-sex physics class, having a female physics teacher, having female scientist guest speakers in physics class, discussing the work of women scientists in physics class, and discussing the under-representation of women in physics class. The effect of these experiences is compared for female students who are matched on several factors, including parental education, prior science/math interests, and academic background, thereby controlling for the effect of many confounding variables.

  6. What Will Dental Practice Be Like In 2025? Will You Help Dental Hypotheses Find Answers

    Directory of Open Access Journals (Sweden)

    Edward F. Rossomando

    2011-02-01

    Full Text Available As a result of the rapid acceptance of digital dental equipment, the dental office of 2011 looks very different from that of 1900. Despite these changes, the general dentist of 2011 performs almost the same functions as in 1900 namely the restoration of decayed teeth and the replacement of those lost due to disease. In addition to changes in technology, the last few decades of the 20th century ushered in a revolution in biology leading to the development of a genomic basis of dental disease and the development of bio-based diagnostics and therapeutics. In 2011 few if any of these bio-discoveries have changed dental practice but by 2025 we expect they will. In this editorial, Dental Hypotheses asks readers to “hypothesize” on what dental practice will be like in 2025.

  7. How do trees die? A test of the hydraulic failure and carbon starvation hypotheses.

    Science.gov (United States)

    Sevanto, Sanna; McDowell, Nate G; Dickman, L Turin; Pangle, Robert; Pockman, William T

    2014-01-01

    Despite decades of research on plant drought tolerance, the physiological mechanisms by which trees succumb to drought are still under debate. We report results from an experiment designed to separate and test the current leading hypotheses of tree mortality. We show that piñon pine (Pinus edulis) trees can die of both hydraulic failure and carbon starvation, and that during drought, the loss of conductivity and carbohydrate reserves can also co-occur. Hydraulic constraints on plant carbohydrate use determined survival time: turgor loss in the phloem limited access to carbohydrate reserves, but hydraulic control of respiration prolonged survival. Our data also demonstrate that hydraulic failure may be associated with loss of adequate tissue carbohydrate content required for osmoregulation, which then promotes failure to maintain hydraulic integrity. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  8. A Review of Hypothesized Determinants Associated with Bighorn Sheep (Ovis canadensis Die-Offs

    Directory of Open Access Journals (Sweden)

    David S. Miller

    2012-01-01

    Full Text Available Multiple determinants have been hypothesized to cause or favor disease outbreaks among free-ranging bighorn sheep (Ovis canadensis populations. This paper considered direct and indirect causes of mortality, as well as potential interactions among proposed environmental, host, and agent determinants of disease. A clear, invariant relationship between a single agent and field outbreaks has not yet been documented, in part due to methodological limitations and practical challenges associated with developing rigorous study designs. Therefore, although there is a need to develop predictive models for outbreaks and validated mitigation strategies, uncertainty remains as to whether outbreaks are due to endemic or recently introduced agents. Consequently, absence of established and universal explanations for outbreaks contributes to conflict among wildlife and livestock stakeholders over land use and management practices. This example illustrates the challenge of developing comprehensive models for understanding and managing wildlife diseases in complex biological and sociological environments.

  9. Endodontic treatment and hypotheses on an unusual case of dens invaginatus.

    Science.gov (United States)

    Demartis, Paola; Dessì, Cristina; Cotti, Marina; Cotti, Elisabetta

    2009-03-01

    This work describes a case of "dens invaginatus" and analyzes the possible aspects of this malformation. An unusual type of dens invaginatus was detected in a young patient corresponding to the maxillary lateral incisor and showing extensive periradicular radiolucency and a vestibular fistula. The radiographic and tomographic examination revealed two apices: one wide open in the distal part of the root and the other normally formed in the mesial. Nonsurgical endodontic treatment was performed by using the "one-step apexification technique," filling both apexes with mineral trioxide aggregate followed by composite resin. The follow-up examination 6 months later showed the healing of the radiolucent area and the healing of the sinus tract. Hypotheses on which was the type of dens invaginatus we had to deal with are formulated.

  10. On the particular vulnerability of face recognition to aging: A review of three hypotheses

    Directory of Open Access Journals (Sweden)

    Isabelle eBoutet

    2015-08-01

    Full Text Available Age-related face recognition deficits are characterized by high false alarms to unfamiliar faces, are not as pronounced for other complex stimuli, and are only partially related to general age-related impairments in cognition. This paper reviews some of the underlying processes likely to be implicated in theses deficits by focusing on areas where contradictions abound as a means to highlight avenues for future research. Research pertaining to three following hypotheses is presented: (i perceptual deterioration, (ii encoding of configural information, and (iii difficulties in recollecting contextual information. The evidence surveyed provides support for the idea that all three factors are likely to contribute, under certain conditions, to the deficits in face recognition seen in older adults. We discuss how these different factors might interact in the context of a generic framework of the different stages implicated in face recognition. Several suggestions for future investigations are outlined.

  11. Attachment and parental divorce: a test of the diffusion and sensitive period hypotheses.

    Science.gov (United States)

    Fraley, R Chris; Heffernan, Marie E

    2013-09-01

    One of the assumptions of attachment theory is that disruptions in parental relationships are prospectively related to insecure attachment patterns in adulthood. The majority of research that has evaluated this hypothesis, however, has been based on retrospective reports of the quality of relationships with parents-research that is subject to retrospective biases. In the present research, the authors examined the impact of parental divorce-an event that can be assessed relatively objectively-on attachment patterns in adulthood across two samples. The data indicate that parental divorce has selective rather than diffuse implications for insecure attachment. Namely, parental divorce was more strongly related to insecure relationships with parents in adulthood than insecure relationships with romantic partners or friends. In addition, parental insecurity was most pronounced when parental divorce took place in early childhood. This finding is consistent with hypotheses about sensitive periods in attachment development.

  12. A Review of Hypothesized Determinants Associated with Bighorn Sheep (Ovis canadensis) Die-Offs

    Science.gov (United States)

    Miller, David S.; Hoberg, Eric; Weiser, Glen; Aune, Keith; Atkinson, Mark; Kimberling, Cleon

    2012-01-01

    Multiple determinants have been hypothesized to cause or favor disease outbreaks among free-ranging bighorn sheep (Ovis canadensis) populations. This paper considered direct and indirect causes of mortality, as well as potential interactions among proposed environmental, host, and agent determinants of disease. A clear, invariant relationship between a single agent and field outbreaks has not yet been documented, in part due to methodological limitations and practical challenges associated with developing rigorous study designs. Therefore, although there is a need to develop predictive models for outbreaks and validated mitigation strategies, uncertainty remains as to whether outbreaks are due to endemic or recently introduced agents. Consequently, absence of established and universal explanations for outbreaks contributes to conflict among wildlife and livestock stakeholders over land use and management practices. This example illustrates the challenge of developing comprehensive models for understanding and managing wildlife diseases in complex biological and sociological environments. PMID:22567546

  13. Mindfulness-based treatment to prevent addictive behavior relapse: theoretical models and hypothesized mechanisms of change.

    Science.gov (United States)

    Witkiewitz, Katie; Bowen, Sarah; Harrop, Erin N; Douglas, Haley; Enkema, Matthew; Sedgwick, Carly

    2014-04-01

    Mindfulness-based treatments are growing in popularity among addiction treatment providers, and several studies suggest the efficacy of incorporating mindfulness practices into the treatment of addiction, including the treatment of substance use disorders and behavioral addictions (i.e., gambling). The current paper provides a review of theoretical models of mindfulness in the treatment of addiction and several hypothesized mechanisms of change. We provide an overview of mindfulness-based relapse prevention (MBRP), including session content, treatment targets, and client feedback from participants who have received MBRP in the context of empirical studies. Future research directions regarding operationalization and measurement, identifying factors that moderate treatment effects, and protocol adaptations for specific populations are discussed.

  14. Can manipulations of cognitive load be used to test evolutionary hypotheses?

    Science.gov (United States)

    Barrett, H Clark; Frederick, David A; Haselton, Martie G; Kurzban, Robert

    2006-09-01

    D. DeSteno, M. Y. Bartlett, J. Braverman, and P. Salovey proposed that if sex-differentiated responses to infidelity are evolved, then they should be automatic, and therefore cognitive load should not attenuate them. DeSteno et al. found smaller sex differences in response to sexual versus emotional infidelity among participants under cognitive load, an effect interpreted as evidence against the evolutionary hypothesis. This logic is faulty. Cognitive load probably affects mechanisms involved in simulating infidelity experiences, thus seriously challenging the usefulness of cognitive load manipulations in testing hypotheses involving simulation. The method also entails the assumption that evolved jealousy mechanisms are necessarily automatic, an assumption not supported by theory or evidence. Regardless of how the jealousy debate is eventually settled, cognitive load manipulations cannot rule out the operation of evolved mechanisms. ((c) 2006 APA, all rights reserved).

  15. Phylogeny and classification of the trapdoor spider genus Myrmekiaphila: an integrative approach to evaluating taxonomic hypotheses.

    Science.gov (United States)

    Bailey, Ashley L; Brewer, Michael S; Hendrixson, Brent E; Bond, Jason E

    2010-09-14

    Revised by Bond and Platnick in 2007, the trapdoor spider genus Myrmekiaphila comprises 11 species. Species delimitation and placement within one of three species groups was based on modifications of the male copulatory device. Because a phylogeny of the group was not available these species groups might not represent monophyletic lineages; species definitions likewise were untested hypotheses. The purpose of this study is to reconstruct the phylogeny of Myrmekiaphila species using molecular data to formally test the delimitation of species and species-groups. We seek to refine a set of established systematic hypotheses by integrating across molecular and morphological data sets. Phylogenetic analyses comprising Bayesian searches were conducted for a mtDNA matrix composed of contiguous 12S rRNA, tRNA-val, and 16S rRNA genes and a nuclear DNA matrix comprising the glutamyl and prolyl tRNA synthetase gene each consisting of 1348 and 481 bp, respectively. Separate analyses of the mitochondrial and nuclear genome data and a concatenated data set yield M. torreya and M. millerae paraphyletic with respect to M. coreyi and M. howelli and polyphyletic fluviatilis and foliata species groups. Despite the perception that molecular data present a solution to a crisis in taxonomy, studies like this demonstrate the efficacy of an approach that considers data from multiple sources. A DNA barcoding approach during the species discovery process would fail to recognize at least two species (M. coreyi and M. howelli) whereas a combined approach more accurately assesses species diversity and illuminates speciation pattern and process. Concomitantly these data also demonstrate that morphological characters likewise fail in their ability to recover monophyletic species groups and result in an unnatural classification. Optimizations of these characters demonstrate a pattern of "Dollo evolution" wherein a complex character evolves only once but is lost multiple times throughout the group

  16. [Co-occurrence of anxiety and autism. The social error and allostatic load hypotheses].

    Science.gov (United States)

    Paula-Perez, Isabel

    2013-02-22

    INTRODUCTION. The concept of comorbidity in neurodevelopmental disorders like autism is sometimes ambiguous. The co-occurrence of anxiety and autism is clinically significant, yet it is not always easy to determine whether it is a 'real' comorbidity, where the two comorbid conditions are phenotypically and aetiologically identical to what that anxiety would mean in persons with a neurotypical development, whether it is an anxiety that has been phenotypically modified by the pathological processes of the autism spectrum disorders, thus resulting in a specific variant of these latter, or whether we are dealing with a false comorbidity resulting from rather inaccurate differential diagnoses. DEVELOPMENT. The article puts forward two hypotheses to explain this co-occurrence, which provide each other with feedback and are little more than our reflections on the scientific evidence we have available today, but expressed aloud. The first is the 'social error' hypothesis, which considers that the maladjustments in the social behaviour of persons with autism (which arises from alterations affecting the processes involved in social cognition) help to aggravate anxiety in autism. The second hypothesis, referring to allostatic load, holds that anxiety is a response to chronic stress, wear or exhaustion that is produced by the hyperactivation of certain structures in the limbic system. CONCLUSIONS. The prototypical manifestations of anxiety present in the person with autism are not always related with the same biopsychosocial variables as those observed in persons without autism. Evidence points to hyper-reactive flee-or-fight responses (hypervigilance) when the person finds him or herself outside their comfort zone, and supports the hypotheses of 'social error' and of decompensation of the allostatic mechanism that makes it possible to cope with stress.

  17. Incentivizing Blood Donation: Systematic Review and Meta-Analysis to Test Titmuss’ Hypotheses

    Science.gov (United States)

    2013-01-01

    Objectives: Titmuss hypothesized that paying blood donors would reduce the quality of the blood donated and would be economically inefficient. We report here the first systematic review to test these hypotheses, reporting on both financial and nonfinancial incentives. Method: Studies deemed eligible for inclusion were peer-reviewed, experimental studies that presented data on the quantity (as a proxy for efficiency) and quality of blood donated in at least two groups: those donating blood when offered an incentive, and those donating blood with no offer of an incentive. The following were searched: MEDLINE, EMBASE and PsycINFO using OVID SP, CINAHL via EBSCO and CENTRAL, the Cochrane Library, Econlit via EBSCO, JSTOR Health and General Science Collection, and Google. Results: The initial search yielded 1100 abstracts, which resulted in 89 full papers being assessed for eligibility, of which seven studies, reported in six papers, met the inclusion criteria. The included studies involved 93,328 participants. Incentives had no impact on the likelihood of donation (OR = 1.22 CI 95% 0.91–1.63; p = .19). There was no difference between financial and nonfinancial incentives in the quantity of blood donated. Of the two studies that assessed quality of blood, one found no effect and the other found an adverse effect from the offer of a free cholesterol test (β = 0.011 p < .05). Conclusion: The limited evidence suggests that Titmuss’ hypothesis of the economic inefficiency of incentives is correct. There is insufficient evidence to assess their likely impact on the quality of the blood provided. PMID:24001244

  18. Incentivizing blood donation: systematic review and meta-analysis to test Titmuss' hypotheses.

    Science.gov (United States)

    Niza, Claudia; Tung, Burcu; Marteau, Theresa M

    2013-09-01

    Titmuss hypothesized that paying blood donors would reduce the quality of the blood donated and would be economically inefficient. We report here the first systematic review to test these hypotheses, reporting on both financial and nonfinancial incentives. Studies deemed eligible for inclusion were peer-reviewed, experimental studies that presented data on the quantity (as a proxy for efficiency) and quality of blood donated in at least two groups: those donating blood when offered an incentive, and those donating blood with no offer of an incentive. The following were searched: MEDLINE, EMBASE and PsycINFO using OVID SP, CINAHL via EBSCO and CENTRAL, the Cochrane Library, Econlit via EBSCO, JSTOR Health and General Science Collection, and Google. The initial search yielded 1100 abstracts, which resulted in 89 full papers being assessed for eligibility, of which seven studies, reported in six papers, met the inclusion criteria. The included studies involved 93,328 participants. Incentives had no impact on the likelihood of donation (OR = 1.22 CI 95% 0.91-1.63; p = .19). There was no difference between financial and nonfinancial incentives in the quantity of blood donated. Of the two studies that assessed quality of blood, one found no effect and the other found an adverse effect from the offer of a free cholesterol test (β = 0.011 p < .05). The limited evidence suggests that Titmuss' hypothesis of the economic inefficiency of incentives is correct. There is insufficient evidence to assess their likely impact on the quality of the blood provided. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  19. Environmental effects on vertebrate species richness: testing the energy, environmental stability and habitat heterogeneity hypotheses.

    Directory of Open Access Journals (Sweden)

    Zhenhua Luo

    Full Text Available BACKGROUND: Explaining species richness patterns is a central issue in biogeography and macroecology. Several hypotheses have been proposed to explain the mechanisms driving biodiversity patterns, but the causes of species richness gradients remain unclear. In this study, we aimed to explain the impacts of energy, environmental stability, and habitat heterogeneity factors on variation of vertebrate species richness (VSR, based on the VSR pattern in China, so as to test the energy hypothesis, the environmental stability hypothesis, and the habitat heterogeneity hypothesis. METHODOLOGY/PRINCIPAL FINDINGS: A dataset was compiled containing the distributions of 2,665 vertebrate species and eleven ecogeographic predictive variables in China. We grouped these variables into categories of energy, environmental stability, and habitat heterogeneity and transformed the data into 100 × 100 km quadrat systems. To test the three hypotheses, AIC-based model selection was carried out between VSR and the variables in each group and correlation analyses were conducted. There was a decreasing VSR gradient from the southeast to the northwest of China. Our results showed that energy explained 67.6% of the VSR variation, with the annual mean temperature as the main factor, which was followed by annual precipitation and NDVI. Environmental stability factors explained 69.1% of the VSR variation and both temperature annual range and precipitation seasonality had important contributions. By contrast, habitat heterogeneity variables explained only 26.3% of the VSR variation. Significantly positive correlations were detected among VSR, annual mean temperature, annual precipitation, and NDVI, whereas the relationship of VSR and temperature annual range was strongly negative. In addition, other variables showed moderate or ambiguous relations to VSR. CONCLUSIONS/SIGNIFICANCE: The energy hypothesis and the environmental stability hypothesis were supported, whereas little

  20. Testing phylogenetic hypotheses of the subgenera of the freshwater crayfish genus Cambarus (Decapoda: Cambaridae.

    Directory of Open Access Journals (Sweden)

    Jesse W Breinholt

    Full Text Available The genus Cambarus is one of three most species rich crayfish genera in the Northern Hemisphere. The genus has its center of diversity in the Southern Appalachians of the United States and has been divided into 12 subgenera. Using Cambarus we test the correspondence of subgeneric designations based on morphology used in traditional crayfish taxonomy to the underlying evolutionary history for these crayfish. We further test for significant correlation and explanatory power of geographic distance, taxonomic model, and a habitat model to estimated phylogenetic distance with multiple variable regression.We use three mitochondrial and one nuclear gene regions to estimate the phylogenetic relationships for species within the genus Cambarus and test evolutionary hypotheses of relationships and associated morphological and biogeographical hypotheses. Our resulting phylogeny indicates that the genus Cambarus is polyphyletic, however we fail to reject the monophyly of Cambarus with a topology test. The majority of the Cambarus subgenera are rejected as monophyletic, suggesting the morphological characters used to define those taxa are subject to convergent evolution. While we found incongruence between taxonomy and estimated phylogenetic relationships, a multiple model regression analysis indicates that taxonomy had more explanatory power of genetic relationships than either habitat or geographic distance.We find convergent evolution has impacted the morphological features used to delimit Cambarus subgenera. Studies of the crayfish genus Orconectes have shown gonopod morphology used to delimit subgenera is also affected by convergent evolution. This suggests that morphological diagnoses based on traditional crayfish taxonomy might be confounded by convergent evolution across the cambarids and has little utility in diagnosing relationships or defining natural groups. We further suggest that convergent morphological evolution appears to be a common

  1. Postulating hypotheses in experimental doctoral dissertations on Applied Linguistics: A qualitative investigation into rhetorical shifts and linguistic mechanisms

    Directory of Open Access Journals (Sweden)

    Jason Miin-Hwa Lim

    2014-03-01

    Full Text Available The extent to which research hypotheses need to be incorporated in experimental studies often becomes a subject of discussion among academics supervising the writing of theses and dissertations. While writers are concerned about how hypotheses can be strategically linked with other elements in research reports to effectively present an introductory chapter, instructors are considering ways of guiding learners to use the appropriate language in postulating research hypotheses. Using an analytical framework developed by Swales (1990 & 2004 and specialist informants’ qualitative data, this largely qualitative investigation looks into a corpus of experimental doctoral dissertations submitted to 32 American universities from 2001 to 2009 in order to ascertain (i the degree to which research hypotheses need to be presented in dissertation introductions, (ii how hypotheses are strategically linked with other rhetorical segments, and (iii the salient linguistic mechanisms used to achieve the communicative functions. This study has revealed (i how writers shift from pertinent communicative moves to the postulation of hypotheses, and (ii the gamut of major language choices employed to postulate these hypotheses. The findings can be used to prepare teaching materials that help learners comprehend and employ the rhetorical strategies and linguistic mechanisms needed in postulating hypotheses in research reports.

  2. 22 CFR 40.91 - Certain aliens previously removed.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Certain aliens previously removed. 40.91... IMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Aliens Previously Removed § 40.91 Certain aliens previously removed. (a) 5-year bar. An alien who has been found inadmissible, whether as a result...

  3. Determining root correspondence between previously and newly detected objects

    Science.gov (United States)

    Paglieroni, David W.; Beer, N Reginald

    2014-06-17

    A system that applies attribute and topology based change detection to networks of objects that were detected on previous scans of a structure, roadway, or area of interest. The attributes capture properties or characteristics of the previously detected objects, such as location, time of detection, size, elongation, orientation, etc. The topology of the network of previously detected objects is maintained in a constellation database that stores attributes of previously detected objects and implicitly captures the geometrical structure of the network. A change detection system detects change by comparing the attributes and topology of new objects detected on the latest scan to the constellation database of previously detected objects.

  4. Evolution of microgastropods (Ellobioidea, Carychiidae): integrating taxonomic, phylogenetic and evolutionary hypotheses

    Science.gov (United States)

    2013-01-01

    Background Current biodiversity patterns are considered largely the result of past climatic and tectonic changes. In an integrative approach, we combine taxonomic and phylogenetic hypotheses to analyze temporal and geographic diversification of epigean (Carychium) and subterranean (Zospeum) evolutionary lineages in Carychiidae (Eupulmonata, Ellobioidea). We explicitly test three hypotheses: 1) morphospecies encompass unrecognized evolutionary lineages, 2) limited dispersal results in a close genetic relationship of geographical proximally distributed taxa and 3) major climatic and tectonic events had an impact on lineage diversification within Carychiidae. Results Initial morphospecies assignments were investigated by different molecular delimitation approaches (threshold, ABGD, GMYC and SP). Despite a conservative delimitation strategy, carychiid morphospecies comprise a great number of unrecognized evolutionary lineages. We attribute this phenomenon to historic underestimation of morphological stasis and phenotypic variability amongst lineages. The first molecular phylogenetic hypothesis for the Carychiidae (based on COI, 16S and H3) reveals Carychium and Zospeum to be reciprocally monophyletic. Geographical proximally distributed lineages are often closely related. The temporal diversification of Carychiidae is best described by a constant rate model of diversification. The evolution of Carychiidae is characterized by relatively few (long distance) colonization events. We find support for an Asian origin of Carychium. Zospeum may have arrived in Europe before extant members of Carychium. Distantly related Carychium clades inhabit a wide spectrum of the available bioclimatic niche and demonstrate considerable niche overlap. Conclusions Carychiid taxonomy is in dire need of revision. An inferred wide distribution and variable phenotype suggest underestimated diversity in Zospeum. Several Carychium morphospecies are results of past taxonomic lumping. By collecting

  5. 3D tooth microwear texture analysis in fishes as a test of dietary hypotheses of durophagy

    International Nuclear Information System (INIS)

    Purnell, Mark A; Darras, Laurent P G

    2016-01-01

    An understanding of how extinct animals functioned underpins our understanding of past evolutionary events, including adaptive radiations, and the role of functional innovation and adaptation as drivers of both micro- and macroevolution. Yet analysis of function in extinct animals is fraught with difficulty. Hypotheses that interpret molariform teeth in fishes as evidence of durophagous (shell-crushing) diets provide a good example of the particular problems inherent in the methods of functional morphology. This is because the assumed close coupling of form and function upon which the approach is based is weakened by, among other things, behavioural flexibility and the absence of a clear one to one relationship between structures and functions. Here we show that ISO 25178-2 standard parameters for surface texture, derived from analysis of worn surfaces of molariform teeth of fishes, vary significantly between species that differ in the amount of hard-shelled prey they consume. Two populations of the Sheepshead Seabream (Archosargus probatocephalus) were studied. This fish is not a dietary specialist, and one of the populations is known to consume more vegetation and less hard-shelled prey than the other; this is reflected in significant differences in their microwear textures. The Archosargus populations differ significantly in their microwear from the specialist shell-crusher Anarhichas lupus (the Atlantic Wolffish). Multivariate analysis of these three groups of fishes lends further support to the relationship between diet and tooth microwear, and provides robust validation of the approach. Application of the multivariate models derived from microwear texture in Archosargus and Anarhichas to a third fish species—the cichlid Astatoreochromis alluaudi—successfully separates wild caught fish that ate hard-shelled prey from lab-raised fish that did not. This cross-taxon validation demonstrates that quantitative analysis of tooth microwear texture can

  6. 3D tooth microwear texture analysis in fishes as a test of dietary hypotheses of durophagy

    Science.gov (United States)

    Purnell, Mark A.; Darras, Laurent P. G.

    2016-03-01

    An understanding of how extinct animals functioned underpins our understanding of past evolutionary events, including adaptive radiations, and the role of functional innovation and adaptation as drivers of both micro- and macroevolution. Yet analysis of function in extinct animals is fraught with difficulty. Hypotheses that interpret molariform teeth in fishes as evidence of durophagous (shell-crushing) diets provide a good example of the particular problems inherent in the methods of functional morphology. This is because the assumed close coupling of form and function upon which the approach is based is weakened by, among other things, behavioural flexibility and the absence of a clear one to one relationship between structures and functions. Here we show that ISO 25178-2 standard parameters for surface texture, derived from analysis of worn surfaces of molariform teeth of fishes, vary significantly between species that differ in the amount of hard-shelled prey they consume. Two populations of the Sheepshead Seabream (Archosargus probatocephalus) were studied. This fish is not a dietary specialist, and one of the populations is known to consume more vegetation and less hard-shelled prey than the other; this is reflected in significant differences in their microwear textures. The Archosargus populations differ significantly in their microwear from the specialist shell-crusher Anarhichas lupus (the Atlantic Wolffish). Multivariate analysis of these three groups of fishes lends further support to the relationship between diet and tooth microwear, and provides robust validation of the approach. Application of the multivariate models derived from microwear texture in Archosargus and Anarhichas to a third fish species—the cichlid Astatoreochromis alluaudi—successfully separates wild caught fish that ate hard-shelled prey from lab-raised fish that did not. This cross-taxon validation demonstrates that quantitative analysis of tooth microwear texture can

  7. The Hydrological Open Air Laboratory (HOAL) in Petzenkirchen: a hypotheses driven observatory

    Science.gov (United States)

    Blöschl, G.; Blaschke, A. P.; Broer, M.; Bucher, C.; Carr, G.; Chen, X.; Eder, A.; Exner-Kittridge, M.; Farnleitner, A.; Flores-Orozco, A.; Haas, P.; Hogan, P.; Kazemi Amiri, A.; Oismüller, M.; Parajka, J.; Silasari, R.; Stadler, P.; Strauß, P.; Vreugdenhil, M.; Wagner, W.; Zessner, M.

    2015-07-01

    Hydrological observatories bear a lot of resemblance to the more traditional research catchment concept but tend to differ in providing more long term facilities that transcend the lifetime of individual projects, are more strongly geared towards performing interdisciplinary research, and are often designed as networks to assist in performing collaborative science. This paper illustrates how the experimental and monitoring setup of an observatory, the 66 ha Hydrological Open Air Laboratory (HOAL) in Petzenkirchen, Lower Austria, has been established in a way that allows meaningful hypothesis testing. The overarching science questions guided site selection, identifying dissertation topics and the base monitoring. The specific hypotheses guided the dedicated monitoring and sampling, individual experiments, and repeated experiments with controlled boundary conditions. The purpose of the HOAL is to advance the understanding of water related flow and transport processes involving sediments, nutrients and microbes in small catchments. The HOAL catchment is ideally suited for this purpose, because it features a range of different runoff generation processes (surface runoff, springs, tile drains, wetlands), the nutrient inputs are known, and it is convenient from a logistic point of view as all instruments can be connected to the power grid and a high speed glassfibre Local Area Network. The multitude of runoff generation mechanisms in the catchment provide a genuine laboratory where hypotheses of flow and transport can be tested, either by controlled experiments or by contrasting sub-regions of different characteristics. This diversity also ensures that the HOAL is representative of a range of catchments around the world and the specific process findings from the HOAL are applicable to a variety of agricultural catchment settings. The HOAL is operated jointly by the Vienna University of Technology and the Federal Agency for Water Management and takes advantage of the

  8. Factors that affect the physical science career interest of female students: Testing five common hypotheses

    Science.gov (United States)

    Hazari, Zahra; Potvin, Geoff; Lock, Robynne M.; Lung, Florin; Sonnert, Gerhard; Sadler, Philip M.

    2013-12-01

    There are many hypotheses regarding factors that may encourage female students to pursue careers in the physical sciences. Using multivariate matching methods on national data drawn from the Persistence Research in Science and Engineering (PRiSE) project (n=7505), we test the following five commonly held beliefs regarding what factors might impact females’ physical science career interest: (i) having a single-sex physics class, (ii) having a female physics teacher, (iii) having female scientist guest speakers in physics class, (iv) discussing the work of female scientists in physics class, and (v) discussing the underrepresentation of women in physics class. The effect of these experiences on physical science career interest is compared for female students who are matched on several factors, including prior science interests, prior mathematics interests, grades in science, grades in mathematics, and years of enrollment in high school physics. No significant effects are found for single-sex classes, female teachers, female scientist guest speakers, and discussing the work of female scientists. However, discussions about women’s underrepresentation have a significant positive effect.

  9. Economic stress in childhood and adulthood, and poor psychological health: three life course hypotheses.

    Science.gov (United States)

    Lindström, Martin; Fridh, Maria; Rosvall, Maria

    2014-02-28

    Investigations of mental health in a life course perspective are scarce. The aim is to investigate associations between economic stress in childhood and adulthood, and poor psychological health in adulthood with reference to the accumulation, critical period and social mobility hypotheses in life course epidemiology. The 2008 public health survey in Skåne is a cross-sectional postal questionnaire study. A random sample was invited which yielded 28,198 respondents aged 18-80 (55% participation). Psychological health was assessed with the GHQ12 instrument. Logistic regression models were used to investigate the associations adjusting for age, country of birth, socioeconomic status, emotional support, instrumental support and trust, and stratifying by sex. The accumulation hypothesis was confirmed because combined childhood and adulthood exposures to economic stress were associated with poor psychological health in a graded manner. The social mobility hypothesis was also confirmed. The critical period hypothesis was not confirmed because both childhood and adulthood economic stress remained significantly associated with poor psychological health in adulthood. Economic stress in childhood is associated with mental health in adulthood. © 2013 Published by Elsevier Ireland Ltd.

  10. Testing competing hypotheses for chronology and intensity of lesser scaup molt during winter and spring migration

    Science.gov (United States)

    Anteau, M.J.; Anteau, A.C.E.; Afton, A.D.

    2011-01-01

    We examined chronology and intensity of molt and their relationships to nutrient reserves (lipid and protein) of Lesser Scaup (Aythya affinis) to test predictions of two competing hypotheses. The "staggered cost" hypothesis states that contour-feather molt is nutritionally costly and should not occur during nutritionally costly periods of the annual cycle unless adequate nutrients are available. The "breeding plumage" hypothesis states that prealternate molt must be complete prior to nesting, regardless of nutrient availability. Males and females were completing prebasic molt during winter (Louisiana) and had similar molt intensities. Females underwent prealternate molt during spring migration (Illinois and Minnesota) and prebreeding (Manitoba) periods; 53% and 93% of females were in moderate to heavy molt in Minnesota and Manitoba, respectively, despite experiencing other substantial nutritional costs. Intensity of prealternate molt was not correlated with lipid reserves even though females, on average, were nutritionally stressed. Molt intensity was not negatively correlated with protein reserves at any location. Chronology and intensity of prealternate molt varied little and were not temporally staggered from other nutritionally costly events. Prealternate molt did not influence nutrient reserves, and nutrient reserves likely were not the ultimate factor influencing chronology or intensity of prealternate molt of females. We surmise that nutrients required for prealternate molt come from exogenous sources and that the "staggered cost" hypothesis does not explain chronology of prealternate molt in female Lesser Scaup; rather, it appears that molt must be complete prior to nesting, consistent with the "breeding plumage" hypothesis. ?? The Cooper Ornithological Society 2011.

  11. Use of spatial analysis to test hypotheses on plant recruitment in a hyper-arid ecosystem.

    Directory of Open Access Journals (Sweden)

    Jan J Quets

    Full Text Available Mounds originating from wind-blown sediment accumulation beneath vegetation (nebkhas often indicate land degradation in dry areas. Thus far, most nebkha research has focused on individual plants. Here, we aimed to explore population-scale processes (up to scales of about 100 m that might explain an observed nebkha landscape pattern. We mapped the Rhazya stricta Decne. population in a 3 ha study site in a hyper-arid region of Saudi Arabia. We compared the spatial patterns of five different cohorts (age classes of observed nebkha host plants to those expected under several hypothesized drivers of recruitment and intraspecific interaction. We found that all R. stricta cohorts had a limited fractional vegetation cover and established in large-scale clusters. This clustering weakened with cohort age, possibly indicating merging of neighboring vegetation patches. Different cohort clusters did not spatially overlap in most cases, indicating that recruitment patterns changed position over time. Strong indications were found that the main drivers underlying R. stricta spatial configurations were allogenic (i.e. not driven by vegetation and dynamic. Most likely these drivers were aeolian-driven sand movement or human disturbance which forced offspring recruitment in spatially dynamic clusters. Competition and facilitation were likely active on the field site too, but apparently had a limited effect on the overall landscape structure.

  12. Use of spatial analysis to test hypotheses on plant recruitment in a hyper-arid ecosystem.

    Science.gov (United States)

    Quets, Jan J; Temmerman, Stijn; El-Bana, Magdy I; Al-Rowaily, Saud L; Assaeed, Abdulaziz M; Nijs, Ivan

    2014-01-01

    Mounds originating from wind-blown sediment accumulation beneath vegetation (nebkhas) often indicate land degradation in dry areas. Thus far, most nebkha research has focused on individual plants. Here, we aimed to explore population-scale processes (up to scales of about 100 m) that might explain an observed nebkha landscape pattern. We mapped the Rhazya stricta Decne. population in a 3 ha study site in a hyper-arid region of Saudi Arabia. We compared the spatial patterns of five different cohorts (age classes) of observed nebkha host plants to those expected under several hypothesized drivers of recruitment and intraspecific interaction. We found that all R. stricta cohorts had a limited fractional vegetation cover and established in large-scale clusters. This clustering weakened with cohort age, possibly indicating merging of neighboring vegetation patches. Different cohort clusters did not spatially overlap in most cases, indicating that recruitment patterns changed position over time. Strong indications were found that the main drivers underlying R. stricta spatial configurations were allogenic (i.e. not driven by vegetation) and dynamic. Most likely these drivers were aeolian-driven sand movement or human disturbance which forced offspring recruitment in spatially dynamic clusters. Competition and facilitation were likely active on the field site too, but apparently had a limited effect on the overall landscape structure.

  13. The madness of Dionysus -- six hypotheses on the illness of Nietzsche.

    Science.gov (United States)

    Tényi, Tamás

    2012-01-01

    Friedrich Nietzsche (1844-1900) is considered as one of the most influential modern thinkers of the last two centuries. The great philosopher and poet developed a mental illness at the age of 44 and died at the age of 56. Pathological examination was not undertaken. At that time Nietzsche was diagnosed as having atypical paralysis progressiva, however recently five other probable diagnoses appeared in literature. Literature search in MEDLINE and Web of Science on the illness of Nietzsche. Six hypotheses were identified: 1. Paralysis progressiva (General paralysis of the insane) 2. Bipolar affective disorder followed by vascular dementia 3. Hereditary form of frontotemporal dementia 4. Brain tumor 5. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) 6. Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome. Developments in neurology and molecular genetics give new perspectives to the secret of Nietzsche's illness and also there is a consensus on the questioning of the original paralysis progressiva concept. As there was no postmortem, the clinical speculations on the medical problems of the great philosopher remain a challenge.

  14. Scientifically based nurture and nature: alternative but non exclusive hypotheses on attention development.

    Science.gov (United States)

    Chiappedi, Matteo; Balottin, Umberto; Baschenis, Ilaria M C; Piazza, Fausta; De Bernardi, Elisabetta; Bejor, Maurizio

    2010-11-01

    Attention is an important neuropsychological function in child development. A lot of literature has been devoted to trying to separate the role of nature (i.e. mainly the genetic basis) from that of nurture (i.e. parenting and life events). The case of preterm born children is an opportunity to try and further study this relationship. We hypothesize that children born preterm might have a reduced attention due to an interaction of factors, to be conceptualized both as nature (mainly the genetic background and the specific consequences of preterm birth and of its complications) and nurture (therapeutic techniques used, alteration in parents-child relationship and so on). The contribution of each of these factors needs to be disembodied from the raw finding of a reduced attention: this is especially important because experience-dependent learning, in which individualized experiences have neural effects, can go on throughout life and this opens interesting rehabilitative possibilities. Different research lines which could be useful to entangle the specific contributions of the above mentioned factors are discussed: the results could in turn inform clinical practice with this highly at risk and increasing in number population, with a view largely corresponding to the one founding the OMS International Classification of Disability, Functioning and Health. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Systems analysis of transcriptome data provides new hypotheses about Arabidopsis root response to nitrate treatments

    Directory of Open Access Journals (Sweden)

    Javier eCanales

    2014-02-01

    Full Text Available Nitrogen (N is an essential macronutrient for plant growth and development. Plants adapt to changes in N availability partly by changes in global gene expression. We integrated publicly available root microarray data under contrasting nitrate conditions to identify new genes and functions important for adaptive nitrate responses in Arabidopsis thaliana roots. Overall, more than two thousand genes exhibited changes in expression in response to nitrate treatments in Arabidopsis thaliana root organs. Global regulation of gene expression by nitrate depends largely on the experimental context. However, despite significant differences from experiment to experiment in the identity of regulated genes, there is a robust nitrate response of specific biological functions. Integrative gene network analysis uncovered relationships between nitrate-responsive genes and eleven highly co-expressed gene clusters (modules. Four of these gene network modules have robust nitrate responsive functions such as transport, signaling and metabolism. Network analysis hypothesized G2-like transcription factors are key regulatory factors controlling transport and signaling functions. Our meta-analysis highlights the role of biological processes not studied before in the context of the nitrate response such as root hair development and provides testable hypothesis to advance our understanding of nitrate responses in plants.

  16. Hallucinations and REM sleep behaviour disorder in Parkinson's disease: dream imagery intrusions and other hypotheses.

    Science.gov (United States)

    Manni, Raffaele; Terzaghi, Michele; Ratti, Pietro-Luca; Repetto, Alessandra; Zangaglia, Roberta; Pacchetti, Claudio

    2011-12-01

    REM sleep behaviour disorder (RBD) is a REM sleep-related parasomnia which may be considered a "dissociated state of wakefulness and sleep", given that conflicting elements of REM sleep (dreaming) and of wakefulness (sustained muscle tone and movements) coexist during the episodes, leading to motor and behavioural manifestations reminiscent of an enacted dream. RBD has been reported in association with α-synucleinopathies: around a third of patients with Parkinson's disease (PD) have full-blown RBD. Recent data indicate that PD patients with RBD are more prone to hallucinations than PD patients without this parasomnia. However it is still not clear why RBD in PD is associated with an increased prevalence of VHs. Data exist which suggest that visual hallucinations in PD may be the result of untimely intrusions of REM visual imagery into wakefulness. RBD, which is characterised by a REM sleep dissociation pattern, might be a condition that particularly favours such intrusions. However, other hypotheses may be advanced. In fact, deficits in attentional, executive, visuoperceptual and visuospatial abilities have been documented in RBD and found to occur far more frequently in PD with RBD than in PD without RBD. Neuropsychological deficits involving visual perception and attentional processes are thought to play an important role in the pathophysiology of VHs. On this basis, RBD in PD could be viewed as a contributory risk factor for VHs. Copyright © 2010 Elsevier Inc. All rights reserved.

  17. What drove reversions to quadrupedality in ornithischian dinosaurs? Testing hypotheses using centre of mass modelling.

    Science.gov (United States)

    Maidment, Susannah C R; Henderson, Donald M; Barrett, Paul M

    2014-11-01

    The exceptionally rare transition to quadrupedalism from bipedal ancestors occurred on three independent occasions in ornithischian dinosaurs. The possible driving forces behind these transitions remain elusive, but several hypotheses-including the development of dermal armour and the expansion of head size and cranial ornamentation-have been proposed to account for this major shift in stance. We modelled the position of the centre of mass (CoM) in several exemplar ornithischian taxa and demonstrate that the anterior shifts in CoM position associated with the development of an enlarged skull ornamented with horns and frills for display/defence may have been one of the drivers promoting ceratopsian quadrupedality. A posterior shift in CoM position coincident with the development of extensive dermal armour in thyreophorans demonstrates this cannot have been a primary causative mechanism for quadrupedality in this clade. Quadrupedalism developed in response to different selective pressures in each ornithischian lineage, indicating different evolutionary pathways to convergent quadrupedal morphology.

  18. Rapid Detection Strategies for the Global Threat of Zika Virus: Current State, New Hypotheses and Limitations

    Directory of Open Access Journals (Sweden)

    Shruti Shukla

    2016-10-01

    Full Text Available The current scenario regarding the widespread Zika virus (ZIKV has resulted in numerous diagnostic studies, specifically in South America and in locations where there is frequent entry of travelers returning from ZIKV-affected areas, including pregnant women with or without clinical symptoms of ZIKV infection. The World Health Organization, WHO, announced that millions of cases of ZIKV are likely to occur in the United States of America in the near future. This situation has created an alarming public health emergency of international concern requiring the detection of this life-threatening viral candidate due to increased cases of newborn microcephaly associated with ZIKV infection. Hence, this review reports possible methods and strategies for the fast and reliable detection of ZIKV with particular emphasis on current updates, knowledge and new hypotheses that might be helpful for medical professionals in poor and developing countries that urgently need to address this problem. In particular, we emphasize liposome-based biosensors. Although these biosensors are currently among the less popular tools for human disease detection, they have become useful tools for the screening and detection of pathogenic bacteria, fungi and viruses because of their versatile advantageous features compared to other sensing devices. This review summarizes the currently available methods employed for the rapid detection of ZIKV and suggests an innovative approach involving the application of a liposome-based hypothesis for the development of new strategies for ZIKV detection and their use as effective biomedicinal tools.

  19. Obesity and Cancer: Existing and New Hypotheses for a Causal Connection

    Directory of Open Access Journals (Sweden)

    Trevor W. Stone

    2018-04-01

    Full Text Available Existing explanations of obesity-associated cancer emphasise direct mutagenic effects of dietary components or hormonal imbalance. Some of these hypotheses are reviewed briefly, but recent evidence suggests a major role for chronic inflammation in cancer risk, possibly involving dietary content. These ideas include the inflammation-induced activation of the kynurenine pathway and its role in feeding and metabolism by activation of the aryl hydrocarbon receptor (AHR and by modulating synaptic transmission in the brain. Evidence for a role of the kynurenine pathway in carcinogenesis then provides a potentially major link between obesity and cancer. A second new hypothesis is based on evidence that serine proteases can deplete cells of the tumour suppressors Deleted in Colorectal Cancer (DCC and neogenin. These enzymes include mammalian chymotryptic proteases released by pro-inflammatory neutrophils and macrophages. Blood levels of chymotrypsin itself increase in parallel with food intake. The mechanistically similar bacterial enzyme subtilisin is widespread in the environment, animal probiotics, meat processing and cleaning products. Simple public health schemes in these areas, with selective serine protease inhibitors and AHR antagonists and could prevent a range of intestinal and other cancers. Keywords: Obesity, Serine proteases, Chymotrypsin, Subtilisin, Dependence receptors, DCC, Kynurenine

  20. Testing hypotheses that link wood anatomy to cavitation resistance and hydraulic conductivity in the genus Acer.

    Science.gov (United States)

    Lens, Frederic; Sperry, John S; Christman, Mairgareth A; Choat, Brendan; Rabaey, David; Jansen, Steven

    2011-05-01

    • Vulnerability to cavitation and conductive efficiency depend on xylem anatomy. We tested a large range of structure-function hypotheses, some for the first time, within a single genus to minimize phylogenetic 'noise' and maximize detection of functionally relevant variation. • This integrative study combined in-depth anatomical observations using light, scanning and transmission electron microscopy of seven Acer taxa, and compared these observations with empirical measures of xylem hydraulics. • Our results reveal a 2 MPa range in species' mean cavitation pressure (MCP). MCP was strongly correlated with intervessel pit structure (membrane thickness and porosity, chamber depth), weakly correlated with pit number per vessel, and not related to pit area per vessel. At the tissue level, there was a strong correlation between MCP and mechanical strength parameters, and some of the first evidence is provided for the functional significance of vessel grouping and thickenings on inner vessel walls. In addition, a strong trade-off was observed between xylem-specific conductivity and MCP. Vessel length and intervessel wall characteristics were implicated in this safety-efficiency trade-off. • Cavitation resistance and hydraulic conductivity in Acer appear to be controlled by a very complex interaction between tissue, vessel network and pit characteristics. © 2010 The Authors. New Phytologist © 2010 New Phytologist Trust.

  1. Some hypotheses regarding the mobile telecommunications services marketing and consumers rights from Romania

    Directory of Open Access Journals (Sweden)

    Nicu Marcu

    2013-06-01

    Full Text Available The current research analysis consumers’ rights concerning personal data processing and confidentiality protection within the public communications sector as they are stated in the 2002/58/CE Directive of the European Parliament and Council from 12th of July 2002. The study objectives are: the way that users/ subscribers get informed about their rights in the field of mobile telephony services; the way that mobile telephony services operators inform their users/ subscribers about the subscription included services; the way that mobile telephony services operators inform their uses/ subscribers about the supplementary services that can be demanded; the rights regarding the personal data processing and confidentiality protection that mobile telephony services consumers agree with; the users/ subscribers rights most frequently broken. The marketing research used a questionnaire based survey during January - March 2013 on a sample of 85 users/ subscribers from Romania. It has a preliminary character, shaping a further investigation activity with a higher thematic coverage and a smaller error under the limit of 5%. The data gathering method was a questionnaire based interview. Data were analyzed using the SPSS informatics program, version 16.0 for Windows. The following statistical functions were used for validating/invalidating the hypotheses: descriptive statistics, factor analysis and correlation function.

  2. In search of a deep psychobiology of hypnosis: visionary hypotheses for a new millennium.

    Science.gov (United States)

    Rossi, E L

    2000-01-01

    This search for the deep psychobiological foundations of hypnosis begins with a review of some of the paradoxes of historical hypnosis and the impasse of current theory. It is proposed that further progress requires a deeper investigation of how psychosocial cues can modulate the mechanisms of healing at the CNS, autonomic, neuroendocrine and cellular-genetic levels. The dynamics of hypnotic communication and healing from the cognitive-behavior level to the cellular-genetic are outlined in four stages: (1) Information transduction between the experiences of consciousness and the limbic-hypothalamic-pituitary system; (2) The psychosomatic network of messenger molecules and their receptors; (3) The immediate early gene protein cascade; and (4) State dependent memory, learning and behavior. Neuroscience research is outlined for its contributions to a mathematical model of how a psychobiological approach to the therapeutic applications of hypnosis and the placebo response could facilitate neurogenesis in the human hippocampus and healing at the cellular-genetic-protein level throughout the body. A series of ten hypotheses is proposed as a guide for theory and research in therapeutic hypnosis utilizing DNA chip technology in the new millennium.

  3. Use of Computational Modeling to Evaluate Hypotheses About the Molecular and Cellular Mechanisms of Bystander Effects

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yuchao; Conolly, Rory B; Andersen, Melvin E.

    2006-11-21

    This report describes the development of a computational systems biology approach to evaluate the hypotheses of molecular and cellular mechanisms of adaptive response to low dose ionizing radiation. Our concept is that computational models of signaling pathways can be developed and linked to biologically based dose response models to evaluate the underlying molecular mechanisms which lead to adaptive response. For development of quantitatively accurate, predictive models, it will be necessary to describe tissues consisting of multiple cell types where the different types each contribute in their own way to the overall function of the tissue. Such a model will probably need to incorporate not only cell type-specific data but also spatial information on the architecture of the tissue and on intercellular signaling. The scope of the current model was more limited. Data obtained in a number of different biological systems were synthesized to describe a chimeric, “average” population cell. Biochemical signaling pathways involved in sensing of DNA damage and in the activation of cell cycle checkpoint controls and the apoptotic path were also included. As with any computational modeling effort, it was necessary to develop these simplified initial descriptions (models) that can be iteratively refined. This preliminary model is a starting point which, with time, can evolve to a level of refinement where large amounts of detailed biological information are synthesized and a capability for robust predictions of dose- and time-response behaviors is obtained.

  4. Computer-mediated communication and interpersonal attraction: an experimental test of two explanatory hypotheses.

    Science.gov (United States)

    Antheunis, Marjolijn L; Valkenburg, Patti M; Peter, Jochen

    2007-12-01

    The aims of this study were (a) to investigate the influence of computer-mediated communication (CMC) on interpersonal attraction and (b) to examine two underlying processes in the CMC-interpersonal attraction relationship. We identified two variables that may mediate the influence of CMC on interpersonal attraction: self-disclosure and direct questioning. Focusing on these potential mediating variables, we tested two explanatory hypotheses: the CMC-induced direct questioning hypothesis and the CMC-induced self-disclosure hypothesis. Eighty-one cross-sex dyads were randomly assigned to one of three experimental conditions: text-only CMC, visual CMC, and face-to-face communication. We did not find a direct effect of CMC on interpersonal attraction. However, we did find two positive indirect effects of text-only CMC on interpersonal attraction: text-only CMC stimulated both self-disclosure and direct questioning, both of which in turn enhanced interpersonal attraction. Results are discussed in light of uncertainty reduction theory and CMC theories.

  5. Thyroid disease awareness is associated with high rates of identifying subjects with previously undiagnosed thyroid dysfunction.

    Science.gov (United States)

    Canaris, Gay J; Tape, Thomas G; Wigton, Robert S

    2013-04-16

    Conventional screening for hypothyroidism is controversial. Although hypothyroidism is underdiagnosed, many organizations do not recommend screening, citing low disease prevalence in unselected populations. We studied attendees at a thyroid health fair, hypothesizing that certain patient characteristics would enhance the yield of testing. We carried out an observational study of participants at a Michigan health fair that focused on thyroid disease. We collected patient-reported symptoms and demographics by questionnaire, and correlated these with the TSH values obtained through the health fair. 794 of 858 health fair attendees participated. Most were women, and over 40% reported a family history of thyroid disease. We identified 97 (12.2%) participants with previously unknown thyroid dysfunction. No symptom or combination of symptoms discriminated between hypothyroid and euthyroid individuals. Hypothyroid and euthyroid participants in the health fair reported each symptom with a similar prevalence (p > 0.01), a prevalence which was very high. In fact, when compared with a previously published case-control study that reported symptoms, the euthyroid health fair participants reported a higher symptom prevalence (range 3.9% to 66.3%, mean 31.5%), than the euthyroid individuals from the case-control study (range 2% to 54%, mean 17.4%). A high proportion of previously undiagnosed thyroid disease was identified at this health fair. We initially hypothesized symptoms would distinguish between thyroid function states. However, this was not the case in this health fair screening population. The prevalence of reported symptoms was similar and high in both euthyroid and hypothyroid participants. Because attendees were self-selected, it is possible that this health fair that focused on thyroid disease attracted participants specifically concerned about thyroid health. Despite the lack of symptom discrimination, the much higher prevalence of hypothyroidism in this study

  6. Bisphosphonate-induced osteonecrosis of the jaws, bone markers, and a hypothesized candidate gene.

    Science.gov (United States)

    Lehrer, Steven; Montazem, André; Ramanathan, Lakshmi; Pessin-Minsley, Melissa; Pfail, John; Stock, Richard G; Kogan, Rita

    2009-01-01

    To determine whether any abnormality in serum bone markers is related to bisphosphonate-induced osteonecrosis of the jaw. We obtained serum bone markers and other relevant endocrine assays on 7 patients with osteonecrosis of the jaws (ONJ). The assays were C-telopeptide, N-telopeptide, bone specific alkaline phosphatase, osteocalcin, intact parathyroid hormone, T3, T4, TSH, and vitamin D 25 hydroxy. Diagnostic criteria for ONJ were those formulated by the American Association of Oral and Maxillofacial Surgeons. Five of our patients were women. Two had metastatic breast cancer and had been treated with zoledronic acid; 1 had also received pamidronate. Three others had osteoporosis and had been treated with daily alendronate. One man had metastatic prostate cancer treated with zoledronic acid. Another man had Gaucher's disease treated with zoledronic acid. All patients had been withdrawn from bisphosphonate for at least 6 months. None was taking or had taken corticosteroids. None of the lesions had shown any significant healing and all were still causing the patients considerable distress, yet the bone markers were within the normal range as measured in our laboratory, except for intact parathyroid hormone, which was slightly elevated in 1 case of metastatic breast cancer (177 pg/mL). We hypothesize that matrix metalloproteinase 2 (MMP2) is a candidate gene for bisphosphonate-induced ONJ for 3 reasons: 1) MMP2 is associated with bone abnormalities which could be related to ONJ. 2) Bisphosphonates are associated with atrial fibrillation, and MMP2 is the only gene known to be associated with both bone abnormalities and atrial fibrillation. 3) A network of disorders and disease genes linked by known disorder-gene associations indicates that cardiovascular disease and bone disease are closely related, suggesting that a single drug such as bisphosphonate, acting on a single gene, MMP2, could have both bone and cardiovascular side effects different from the osteoclast

  7. EXAMINING HYPOTHESES GENERATED BY FIELD MEASURES OF SEXUAL SELECTION ON MALE LIZARDS, UTA PALMERI.

    Science.gov (United States)

    Hews, Diana K

    1990-12-01

    I examined sexual selection in the iguanid lizard Uta palmeri by measuring phenotypic selection in a cohort of males. Relative fitness was estimated by copulation rate from one breeding season, and I analyzed selection on five morphological traits (snout-vent length, mass, jaw length, head width, and head depth) and on male territory quality. Only territory quality and head depth were identified as direct targets of selection in a linear selection gradient analysis. Head depth was suggested to also be subject to quadratic selection. All traits exhibited significant directional selection differentials, suggesting indirect selection also was present because of the correlation of these traits with direct targets of selection. I used these results to generate hypotheses about the mechanisms of selection. For traits not identified as direct targets of selection (snout-vent length, mass, head width, jaw length), I could accept the null hypothesis of no female preference for the analyzed male traits; if these morphological traits were preferred by females in mate choice, they would have been identified as direct targets of selection. Exploring possible functional relationships within the cohort, I found that all five morphological traits contributed to explaining variation in territorial status. And in staged aggressive interactions between males that were similar in snout-vent length and mass, winning was associated only with greater head depth and not with head width or jaw length. Several possible interpretations of these results are presented. This study suggests that differential mating success arising from variation in territory quality gives rise to indirect selection on morphology. The possible mechanisms giving rise to the proposed direct selection on head depth require further study. © 1990 The Society for the Study of Evolution.

  8. Examining competing hypotheses for the effects of diagrams on recall for text.

    Science.gov (United States)

    Ortegren, Francesca R; Serra, Michael J; England, Benjamin D

    2015-01-01

    Supplementing text-based learning materials with diagrams typically increases students' free recall and cued recall of the presented information. In the present experiments, we examined competing hypotheses for why this occurs. More specifically, although diagrams are visual, they also serve to repeat information from the text they accompany. Both visual presentation and repetition are known to aid students' recall of information. To examine to what extent diagrams aid recall because they are visual or repetitive (or both), we had college students in two experiments (n = 320) read a science text about how lightning storms develop before completing free-recall and cued-recall tests over the presented information. Between groups, we manipulated the format and repetition of target pieces of information in the study materials using a 2 (visual presentation of target information: diagrams present vs. diagrams absent) × 2 (repetition of target information: present vs. absent) between-participants factorial design. Repetition increased both the free recall and cued recall of target information, and this occurred regardless of whether that repetition was in the form of text or a diagram. In contrast, the visual presentation of information never aided free recall. Furthermore, visual presentation alone did not significantly aid cued recall when participants studied the materials once before the test (Experiment 1) but did when they studied the materials twice (Experiment 2). Taken together, the results of the present experiments demonstrate the important role of repetition (i.e., that diagrams repeat information from the text) over the visual nature of diagrams in producing the benefits of diagrams for recall.

  9. Kinetics of cancer: a method to test hypotheses of genetic causation

    Directory of Open Access Journals (Sweden)

    Lipkin Steven M

    2005-12-01

    Full Text Available Abstract Background Mouse studies have recently compared the age-onset patterns of cancer between different genotypes. Genes associated with earlier onset are tentatively assigned a causal role in carcinogenesis. These standard analyses ignore the great amount of information about kinetics contained in age-onset curves. We present a method for analyzing kinetics that measures quantitatively the causal role of candidate genes in cancer progression. We use our method to demonstrate a clear association between somatic mutation rates of different DNA mismatch repair (MMR genotypes and the kinetics of cancer progression. Methods Most experimental studies report age-onset curves as the fraction diagnosed with tumors at each age for each group. We use such data to estimate smoothed survival curves, then measure incidence rates at each age by the slope of the fitted curve divided by the fraction of mice that remain undiagnosed for tumors at that age. With the estimated incidence curves, we compare between different genotypes the median age of cancer onset and the acceleration of cancer, which is the rate of increase in incidence with age. Results The direction of change in somatic mutation rate between MMR genotypes predicts the direction of change in the acceleration of cancer onset in all 7 cases (p ˜ 0.008, with the same result for the association between mutation rate and the median age of onset. Conclusion Many animal experiments compare qualitatively the onset curves for different genotypes. If such experiments were designed to analyze kinetics, the research could move to the next stage in which the mechanistic consequences of particular genetic pathways are related to the dynamics of carcinogenesis. The data we analyzed here were not collected to test mechanistic and quantitative hypotheses about kinetics. Even so, a simple reanalysis revealed significant insights about how DNA repair genotypes affect separately the age of onset and the

  10. Functional relations between locomotor performance traits in spiders and implications for evolutionary hypotheses

    Directory of Open Access Journals (Sweden)

    Taylor Phillip W

    2010-11-01

    Full Text Available Abstract Background Locomotor performance in ecologically relevant activities is often linked to individual fitness. Recent controversy over evolution of extreme sexual size dimorphism (SSD in spiders centres on the relationship between size and locomotor capacity in males. Advantages for large males running over horizontal surfaces and small males climbing vertically have been proposed. Models have implicitly treated running and climbing as functionally distinct activities and failed to consider the possibility that they reflect common underlying capacities. Findings We examine the relationship between maximum climbing and running performance in males of three spider species. Maximum running and climbing speeds were positively related in two orb-web spiders with high SSD (Argiope keyserlingi and Nephila plumipes, indicating that for these species assays of running and climbing largely reveal the same underlying capacities. Running and climbing speeds were not related in a jumping spider with low SSD (Jacksonoides queenslandica. We found no evidence of a performance trade-off between these activities. Conclusions In the web-spiders A. keyserlingi and N. plumipes good runners were also good climbers. This indicates that climbing and running largely represent a single locomotor performance characteristic in these spiders, but this was not the case for the jumping spider J. queenslandica. There was no evidence of a trade-off between maximum running and climbing speeds in these spiders. We highlight the need to establish the relationship between apparently disparate locomotor activities when testing alternative hypotheses that yield predictions about different locomotor activities. Analysis of slopes suggests greater potential for an evolutionary response on performance in the horizontal compared to vertical context in these spiders.

  11. Cholinergic Hypofunction in Presbycusis-Related Tinnitus With Cognitive Function Impairment: Emerging Hypotheses

    Directory of Open Access Journals (Sweden)

    Qingwei Ruan

    2018-04-01

    Full Text Available Presbycusis (age-related hearing loss is a potential risk factor for tinnitus and cognitive deterioration, which result in poor life quality. Presbycusis-related tinnitus with cognitive impairment is a common phenotype in the elderly population. In these individuals, the central auditory system shows similar pathophysiological alterations as those observed in Alzheimer’s disease (AD, including cholinergic hypofunction, epileptiform-like network synchronization, chronic inflammation, and reduced GABAergic inhibition and neural plasticity. Observations from experimental rodent models indicate that recovery of cholinergic function can improve memory and other cognitive functions via acetylcholine-mediated GABAergic inhibition enhancement, nicotinic acetylcholine receptor (nAChR-mediated anti-inflammation, glial activation inhibition and neurovascular protection. The loss of cholinergic innervation of various brain structures may provide a common link between tinnitus seen in presbycusis-related tinnitus and age-related cognitive impairment. We hypothesize a key component of the condition is the withdrawal of cholinergic input to a subtype of GABAergic inhibitory interneuron, neuropeptide Y (NPY neurogliaform cells. Cholinergic denervation might not only cause the degeneration of NPY neurogliaform cells, but may also result in decreased AChR activation in GABAergic inhibitory interneurons. This, in turn, would lead to reduced GABA release and inhibitory regulation of neural networks. Reduced nAChR-mediated anti-inflammation due to the loss of nicotinic innervation might lead to the transformation of glial cells and release of inflammatory mediators, lowering the buffering of extracellular potassium and glutamate metabolism. Further research will provide evidence for the recovery of cholinergic function with the use of cholinergic input enhancement alone or in combination with other rehabilitative interventions to reestablish inhibitory regulation

  12. The wings before the bird: an evaluation of flapping-based locomotory hypotheses in bird antecedents

    Directory of Open Access Journals (Sweden)

    T. Alexander Dececchi

    2016-07-01

    Full Text Available Background: Powered flight is implicated as a major driver for the success of birds. Here we examine the effectiveness of three hypothesized pathways for the evolution of the flight stroke, the forelimb motion that powers aerial locomotion, in a terrestrial setting across a range of stem and basal avians: flap running, Wing Assisted Incline Running (WAIR, and wing-assisted leaping. Methods: Using biomechanical mathematical models based on known aerodynamic principals and in vivo experiments and ground truthed using extant avians we seek to test if an incipient flight stroke may have contributed sufficient force to permit flap running, WAIR, or leaping takeoff along the phylogenetic lineage from Coelurosauria to birds. Results: None of these behaviours were found to meet the biomechanical threshold requirements before Paraves. Neither was there a continuous trend of refinement for any of these biomechanical performances across phylogeny nor a signal of universal applicability near the origin of birds. None of these flap-based locomotory models appear to have been a major influence on pre-flight character acquisition such as pennaceous feathers, suggesting non-locomotory behaviours, and less stringent locomotory behaviours such as balancing and braking, played a role in the evolution of the maniraptoran wing and nascent flight stroke. We find no support for widespread prevalence of WAIR in non-avian theropods, but can’t reject its presence in large winged, small-bodied taxa like Microraptor and Archaeopteryx. Discussion: Using our first principles approach we find that “near flight” locomotor behaviors are most sensitive to wing area, and that non-locomotory related selection regimes likely expanded wing area well before WAIR and other such behaviors were possible in derived avians. These results suggest that investigations of the drivers for wing expansion and feather elongation in theropods need not be intrinsically linked to locomotory

  13. Cholinergic Hypofunction in Presbycusis-Related Tinnitus With Cognitive Function Impairment: Emerging Hypotheses.

    Science.gov (United States)

    Ruan, Qingwei; Yu, Zhuowei; Zhang, Weibin; Ruan, Jian; Liu, Chunhui; Zhang, Ruxin

    2018-01-01

    Presbycusis (age-related hearing loss) is a potential risk factor for tinnitus and cognitive deterioration, which result in poor life quality. Presbycusis-related tinnitus with cognitive impairment is a common phenotype in the elderly population. In these individuals, the central auditory system shows similar pathophysiological alterations as those observed in Alzheimer's disease (AD), including cholinergic hypofunction, epileptiform-like network synchronization, chronic inflammation, and reduced GABAergic inhibition and neural plasticity. Observations from experimental rodent models indicate that recovery of cholinergic function can improve memory and other cognitive functions via acetylcholine-mediated GABAergic inhibition enhancement, nicotinic acetylcholine receptor (nAChR)-mediated anti-inflammation, glial activation inhibition and neurovascular protection. The loss of cholinergic innervation of various brain structures may provide a common link between tinnitus seen in presbycusis-related tinnitus and age-related cognitive impairment. We hypothesize a key component of the condition is the withdrawal of cholinergic input to a subtype of GABAergic inhibitory interneuron, neuropeptide Y (NPY) neurogliaform cells. Cholinergic denervation might not only cause the degeneration of NPY neurogliaform cells, but may also result in decreased AChR activation in GABAergic inhibitory interneurons. This, in turn, would lead to reduced GABA release and inhibitory regulation of neural networks. Reduced nAChR-mediated anti-inflammation due to the loss of nicotinic innervation might lead to the transformation of glial cells and release of inflammatory mediators, lowering the buffering of extracellular potassium and glutamate metabolism. Further research will provide evidence for the recovery of cholinergic function with the use of cholinergic input enhancement alone or in combination with other rehabilitative interventions to reestablish inhibitory regulation mechanisms of

  14. Confidence judgment in depression and dysphoria: the depressive realism vs. negativity hypotheses.

    Science.gov (United States)

    Szu-Ting Fu, Tiffany; Koutstaal, Wilma; Poon, Lucia; Cleare, Anthony J

    2012-06-01

    According to the negativity hypothesis, depressed individuals are over-pessimistic due to negative self-concepts. In contrast, depressive realism suggests that depressed persons are realistic compared to their nondepressed controls. However, evidence supporting depressive realism predominantly comes from judgment comparisons between controls and nonclinical dysphoric samples when the controls showed overconfident bias. This study aimed to test the validity of the two accounts in clinical depression and dysphoria. Sixty-eight participants, including healthy controls (n = 32), patients with DSM-IV major depression (n = 20), and dysphoric participants with CDC-defined chronic fatigue syndrome (n = 16) performed an adjective recognition task and reported their item-by-item confidence judgments and post-test performance estimate (PTPE). Compared to realistic PTPE made by the controls, patients with major depression showed significant underconfidence. The PTPE of the dysphoric participants was relatively accurate. Both the depressed and dysphoric participants displayed less item-by-item overconfidence as opposed to significant item-by-item overconfidence shown by the controls. The judgment-accuracy patterns of the three groups need to be replicated with larger samples using non-memory task domains. The present study confirms depressive realism in dysphoric individuals. However, toward a more severe depressive emotional state, the findings did not support depressive realism but are in line with the prediction of the negativity hypothesis. It is not possible to determine the validity of the two hypotheses when the controls are overconfident. Dissociation between item-by-item and retrospective confidence judgments is discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Retraining the addicted brain: a review of hypothesized neurobiological mechanisms of mindfulness-based relapse prevention.

    Science.gov (United States)

    Witkiewitz, Katie; Lustyk, M Kathleen B; Bowen, Sarah

    2013-06-01

    Addiction has generally been characterized as a chronic relapsing condition (Leshner, 1999). Several laboratory, preclinical, and clinical studies have provided evidence that craving and negative affect are strong predictors of the relapse process. These states, as well as the desire to avoid them, have been described as primary motives for substance use. A recently developed behavioral treatment, mindfulness-based relapse prevention (MBRP), was designed to target experiences of craving and negative affect and their roles in the relapse process. MBRP offers skills in cognitive-behavioral relapse prevention integrated with mindfulness meditation. The mindfulness practices in MBRP are intended to increase discriminative awareness, with a specific focus on acceptance of uncomfortable states or challenging situations without reacting "automatically." A recent efficacy trial found that those randomized to MBRP, as compared with those in a control group, demonstrated significantly lower rates of substance use and greater decreases in craving following treatment. Furthermore, individuals in MBRP did not report increased craving or substance use in response to negative affect. It is important to note, areas of the brain that have been associated with craving, negative affect, and relapse have also been shown to be affected by mindfulness training. Drawing from the neuroimaging literature, we review several plausible mechanisms by which MBRP might be changing neural responses to the experiences of craving and negative affect, which subsequently may reduce risk for relapse. We hypothesize that MBRP may affect numerous brain systems and may reverse, repair, or compensate for the neuroadaptive changes associated with addiction and addictive-behavior relapse. 2013 APA, all rights reserved

  16. Linking Network Activity to Synaptic Plasticity during Sleep: Hypotheses and Recent Data.

    Science.gov (United States)

    Puentes-Mestril, Carlos; Aton, Sara J

    2017-01-01

    Research findings over the past two decades have supported a link between sleep states and synaptic plasticity. Numerous mechanistic hypotheses have been put forth to explain this relationship. For example, multiple studies have shown structural alterations to synapses (including changes in synaptic volume, spine density, and receptor composition) indicative of synaptic weakening after a period of sleep. Direct measures of neuronal activity and synaptic strength support the idea that a period of sleep can reduce synaptic strength. This has led to the synaptic homeostasis hypothesis (SHY), which asserts that during slow wave sleep, synapses are downscaled throughout the brain to counteract net strengthening of network synapses during waking experience (e.g., during learning). However, neither the cellular mechanisms mediating these synaptic changes, nor the sleep-dependent activity changes driving those cellular events are well-defined. Here we discuss potential cellular and network dynamic mechanisms which could underlie reductions in synaptic strength during sleep. We also discuss recent findings demonstrating circuit-specific synaptic strengthening (rather than weakening) during sleep. Based on these data, we explore the hypothetical role of sleep-associated network activity patterns in driving synaptic strengthening. We propose an alternative to SHY-namely that depending on experience during prior wake, a variety of plasticity mechanisms may operate in the brain during sleep. We conclude that either synaptic strengthening or synaptic weakening can occur across sleep, depending on changes to specific neural circuits (such as gene expression and protein translation) induced by experiences in wake. Clarifying the mechanisms underlying these different forms of sleep-dependent plasticity will significantly advance our understanding of how sleep benefits various cognitive functions.

  17. Environmental isotopes to test hypotheses for fluid mud (mud bank) generation mechanisms along the southwest coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Jacob, N.; Ansari, M.A.; Revichandran, C.

    Occurrence of fluid mud (mud banks) in the southwest coast of India is an enigma for the scientific community. Over the years, several multi-disciplinary studies were conducted and various hypotheses were postulated on the occurrence and sustenance...

  18. 2 CFR 1.215 - Relationship to previous issuances.

    Science.gov (United States)

    2010-01-01

    ... 2 Grants and Agreements 1 2010-01-01 2010-01-01 false Relationship to previous issuances. 1.215 Section 1.215 Grants and Agreements ABOUT TITLE 2 OF THE CODE OF FEDERAL REGULATIONS AND SUBTITLE A Introduction toSubtitle A § 1.215 Relationship to previous issuances. Although some of the guidance was...

  19. 2 CFR 230.45 - Relationship to previous issuance.

    Science.gov (United States)

    2010-01-01

    ... 2 Grants and Agreements 1 2010-01-01 2010-01-01 false Relationship to previous issuance. 230.45 Section 230.45 Grants and Agreements OFFICE OF MANAGEMENT AND BUDGET CIRCULARS AND GUIDANCE Reserved COST PRINCIPLES FOR NON-PROFIT ORGANIZATIONS (OMB CIRCULAR A-122) § 230.45 Relationship to previous issuance. (a...

  20. Research Note Effects of previous cultivation on regeneration of ...

    African Journals Online (AJOL)

    Research Note Effects of previous cultivation on regeneration of Julbernadia globiflora and Brachystegia spiciformis in grazing areas of Mupfurudzi ... Plant attributes for Julbernadia globiflora and Brachystegia spiciformis were measured in previously cultivated and uncultivated sites making up rangelands of the scheme.

  1. 49 CFR 173.23 - Previously authorized packaging.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Previously authorized packaging. 173.23 Section... REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS Preparation of Hazardous Materials for Transportation § 173.23 Previously authorized packaging. (a) When the regulations specify a packaging with a specification marking...

  2. 75 FR 76056 - FEDERAL REGISTER CITATION OF PREVIOUS ANNOUNCEMENT:

    Science.gov (United States)

    2010-12-07

    ... SECURITIES AND EXCHANGE COMMISSION Sunshine Act Meeting FEDERAL REGISTER CITATION OF PREVIOUS ANNOUNCEMENT: STATUS: Closed meeting. PLACE: 100 F Street, NE., Washington, DC. DATE AND TIME OF PREVIOUSLY ANNOUNCED MEETING: Thursday, December 9, 2010 at 2 p.m. CHANGE IN THE MEETING: Time change. The closed...

  3. Triple outlet right ventricle: a previously unknown cardiac malformation.

    Science.gov (United States)

    Tingo, Jennifer E; Carroll, Sheila J; Crystal, Matthew A

    2015-03-01

    We present the case of an infant with three distinct outflow tracts from the right ventricle. Three outlets from the heart have been previously named the "Tritruncal Heart". We review the two previously reported cases of tritruncal hearts and describe the anatomy, diagnosis, surgical management, and outcome of our case. Embryologic implications are also discussed.

  4. Implant breast reconstruction after salvage mastectomy in previously irradiated patients.

    Science.gov (United States)

    Persichetti, Paolo; Cagli, Barbara; Simone, Pierfranco; Cogliandro, Annalisa; Fortunato, Lucio; Altomare, Vittorio; Trodella, Lucio

    2009-04-01

    The most common surgical approach in case of local tumor recurrence after quadrantectomy and radiotherapy is salvage mastectomy. Breast reconstruction is the subsequent phase of the treatment and the plastic surgeon has to operate on previously irradiated and manipulated tissues. The medical literature highlights that breast reconstruction with tissue expanders is not a pursuable option, considering previous radiotherapy a contraindication. The purpose of this retrospective study is to evaluate the influence of previous radiotherapy on 2-stage breast reconstruction (tissue expander/implant). Only patients with analogous timing of radiation therapy and the same demolitive and reconstructive procedures were recruited. The results of this study prove that, after salvage mastectomy in previously irradiated patients, implant reconstruction is still possible. Further comparative studies are, of course, advisable to draw any conclusion on the possibility to perform implant reconstruction in previously irradiated patients.

  5. No discrimination against previous mates in a sexually cannibalistic spider

    Science.gov (United States)

    Fromhage, Lutz; Schneider, Jutta M.

    2005-09-01

    In several animal species, females discriminate against previous mates in subsequent mating decisions, increasing the potential for multiple paternity. In spiders, female choice may take the form of selective sexual cannibalism, which has been shown to bias paternity in favor of particular males. If cannibalistic attacks function to restrict a male's paternity, females may have little interest to remate with males having survived such an attack. We therefore studied the possibility of female discrimination against previous mates in sexually cannibalistic Argiope bruennichi, where females almost always attack their mate at the onset of copulation. We compared mating latency and copulation duration of males having experienced a previous copulation either with the same or with a different female, but found no evidence for discrimination against previous mates. However, males copulated significantly shorter when inserting into a used, compared to a previously unused, genital pore of the female.

  6. Female and male moths display different reproductive behavior when facing new versus previous mates.

    Science.gov (United States)

    Li, Yan-Ying; Yu, Jin-Feng; Lu, Qin; Xu, Jin; Ye, Hui

    2014-01-01

    Multiple mating allows females to obtain material (more sperm and nutrient) and/or genetic benefits. The genetic benefit models require sperm from different males to fertilize eggs competitively or the offspring be fathered by multiple males. To maximize genetic benefits from multiple mating, females have evolved strategies to prefer novel versus previous mates in their subsequent matings. However, the reproductive behavior during mate encounter, mate choice and egg laying in relation to discrimination and preference between sexes has been largely neglected. In the present study, we used novel and previous mate treatments and studied male and female behavior and reproductive output in Spodoptera litura. The results of this study do not support the sperm and nutrient replenishment hypotheses because neither the number of mates nor the number of copulations achieved by females significantly increased female fecundity, fertility and longevity. However, females showed different oviposition patterns when facing new versus previous mates by slowing down oviposition, which allows the last male has opportunities to fertilize her eggs and the female to promote offspring diversity. Moreover, females that have novel males present called earlier and more than females that have their previous mates present, whereas no significant differences were found on male courtship between treatments. These results suggest that S. litura females can distinguish novel from previous mates and prefer the former, whereas males generally remate regardless of whether the female is a previous mate or not. In S. litura, eggs are laid in large clusters and offspring competition, inbreeding and disease transfer risks are thus increased. Therefore, offspring diversity should be valuable for S. litura, and genetic benefits should be the main force behind the evolution of female behavioral strategies found in the present study.

  7. Female and male moths display different reproductive behavior when facing new versus previous mates.

    Directory of Open Access Journals (Sweden)

    Yan-Ying Li

    Full Text Available Multiple mating allows females to obtain material (more sperm and nutrient and/or genetic benefits. The genetic benefit models require sperm from different males to fertilize eggs competitively or the offspring be fathered by multiple males. To maximize genetic benefits from multiple mating, females have evolved strategies to prefer novel versus previous mates in their subsequent matings. However, the reproductive behavior during mate encounter, mate choice and egg laying in relation to discrimination and preference between sexes has been largely neglected. In the present study, we used novel and previous mate treatments and studied male and female behavior and reproductive output in Spodoptera litura. The results of this study do not support the sperm and nutrient replenishment hypotheses because neither the number of mates nor the number of copulations achieved by females significantly increased female fecundity, fertility and longevity. However, females showed different oviposition patterns when facing new versus previous mates by slowing down oviposition, which allows the last male has opportunities to fertilize her eggs and the female to promote offspring diversity. Moreover, females that have novel males present called earlier and more than females that have their previous mates present, whereas no significant differences were found on male courtship between treatments. These results suggest that S. litura females can distinguish novel from previous mates and prefer the former, whereas males generally remate regardless of whether the female is a previous mate or not. In S. litura, eggs are laid in large clusters and offspring competition, inbreeding and disease transfer risks are thus increased. Therefore, offspring diversity should be valuable for S. litura, and genetic benefits should be the main force behind the evolution of female behavioral strategies found in the present study.

  8. Study design, objectives, hypotheses, main findings, health consequences for the population exposed, rationale of future research

    Energy Technology Data Exchange (ETDEWEB)

    Trnovec, T.; Kocan, A. [Slovak Medical Univ., Bratislava (Slovakia); Bencko, V. [Charles Univ., Prague (Czech Republic); Langer, P. [Institute of Experimental Endocrinology SAS, Bratislava (Slovakia); Berg, M. van den [Rijksuniversiteit Utrecht (Netherlands); Bergman, A. [Stockholm Univ. (Sweden); Hustak, M. [Air Force Military Hospital, Kosics (Slovakia)

    2004-09-15

    pesticides, polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) within a population that has been exposed to these chemicals as a result of environmental pollution. The hypotheses tested are closely related to these objectives. The basic hypothesis that can be further developed for a particular compound of interest and health outcome is as follows: ''Is there any association between a certain type of health outcome investigated and the organochlorine exposure?'' Any of the project objectives was targeted at the place of residence as a predictor of any health outcome.

  9. Declines of greater and lesser scaup populations: issues, hypotheses, and research needs

    Science.gov (United States)

    Austin, J.E.; Afton, A.D.; Anderson, M.G.; Clark, R.G.; Custer, Christine M.; Lawrence, J.; Pollard, J.B.; Ringelman, J.K.

    2000-01-01

    The population estimate for greater (Aythya marila) and lesser (Aythya affinis) scaup (combined) has declined dramatically since the early 1980s to record lows in 1998. The 1998 estimate of 3.47 million scaup is far below the goal of 6.3 million set in the North American Waterfowl Management Plan (NAWMP), causing concern among biologists and hunters. We summarize issues of concern, hypotheses for factors contributing to the population decline, and research and management needs recommended by participants of the Scaup Workshop, held in September 1999. We believe that contaminants, lower female survival, and reduced recruitment due to changes in food resources or breeding-ground habitats are primary factors contributing to the decline. These factors are not mutually exclusive but likely interact across seasons. Workshop participants identified seven action items. We need to further delineate where declines in breeding populations have occurred, with a primary focus on the western Canadian boreal forest, where declines appear to be most pronounced. Productivity in various areas and habitats throughout the breeding range needs to be assessed by conducting retrospective analyses of existing data and by intensive field studies at broad and local scales. Annual and seasonal survival rates need to be determined in order to assess the role of harvest or natural mortality. Effects of contaminants on reproduction, female body condition, and behavior must be investigated. Use, distribution, and role of food resources relative to body condition and reproduction need to be examined to better understand seasonal dynamics of nutrient reserves and the role in reproductive success. Affiliations among breeding, migration, and wintering areas must be assessed in order to understand differential exposure to harvest or contaminants, and differential reproductive success and recruitment. Biologists and agencies need to gather and improve information needed to manage greater and lesser

  10. Testing hypotheses for the use of Icelandic volcanic ashes as low cost, natural fertilizers

    Science.gov (United States)

    Seward, W.; Edwards, B.

    2012-04-01

    Andisols are soils derived from tephra/volcanic bedrock and are generally considered to be fertile for plant growth (cf. University of Hawaii at Manoa, CTAHR). However, few studies have been published examining the immediate effects of the addition of volcanic ash to soils immediately after an eruption. Our research is motivated by unpublished accounts from Icelandic farmers that the growing season following the 2010 Eyjafjallajökull eruption ended with unusually high yields in areas that were covered by ash from the eruption early in the spring. To test the hypothesis that addition of volcanic ash to soil would have no immediate effect on plant growth, we conducted a ~6 week growth experiment in at controlled environment at the Dickinson College Farm. The experiment used relatively fast growing grain seeds as a test crop, controlled watering, known quantities of peat as an organic base, and the following general experimental design: peat was mixed in known but systematically differing proportions with 1) commercial quartz sand, 2) basaltic ash from the 2004 Grimsvötn eruption, and 3) trachyandesite ash from the 2010 Eyjafjallajökull eruption. For all experiments, the seeds growing in the simulated soil created with the two different composition volcanic ash had higher germination rates, higher growth rates, and produced plants that were healthier in appearance than the soil made from peat mixed with quartz sand. Some differences were also noted between the germination and grow rates between the basaltic and trachyandesitic ash experiments as well. Working hypotheses to explain these results include (1) shard shapes and vesicles from volcanic ash provide better water retention than quartz, allowing water to be stored longer and increasing average soil moisture, and (2) chemical nutrients from the ash facilitate germination and growth of plants. Documenting the potential benefits of fresh volcanic ash as a fertilizer is important as use of fresh ash fertlizer

  11. Dopamine in the Brain: Hypothesizing Surfeit or Deficit Links to Reward and Addiction.

    Science.gov (United States)

    Blum, Kenneth; Thanos, Peter K; Oscar-Berman, Marlene; Febo, Marcelo; Baron, David; Badgaiyan, Rajendra D; Gardner, Eliot; Demetrovics, Zsolt; Fahlke, Claudia; Haberstick, Brett C; Dushaj, Kristina; Gold, Mark S

    Recently there has been debate concerning the role of brain dopamine in reward and addiction. David Nutt and associates eloquently proposed that dopamine (DA) may be central to psycho stimulant dependence and some what important for alcohol, but not important for opiates, nicotine or even cannabis. Others have also argued that surfeit theories can explain for example cocaine seeking behavior as well as non-substance-related addictive behaviors. It seems prudent to distinguish between what constitutes "surfeit" compared to" deficit" in terms of short-term (acute) and long-term (chronic) brain reward circuitry responsivity. In an attempt to resolve controversy regarding the contributions of mesolimbic DA systems to reward, we review the three main competing explanatory categories: "liking", "learning", and "wanting". They are (a) the hedonic impact -liking reward, (b) the ability to predict rewarding effects-learning and (c) the incentive salience of reward-related stimuli -wanting. In terms of acute effects, most of the evidence seems to favor the "surfeit theory". Due to preferential dopamine release at mesolimbic-VTA-caudate-accumbens loci most drugs of abuse and Reward Deficiency Syndrome (RDS) behaviors have been linked to heightened feelings of well-being and hyperdopaminergic states.The "dopamine hypotheses" originally thought to be simple, is now believed to be quite complex and involves encoding the set point of hedonic tone, encoding attention, reward expectancy, and incentive motivation. Importantly, Willuhn et al. shows that in a self-administration paradigm, (chronic) excessive use of cocaine is caused by decreased phasic dopamine signaling in the striatum. In terms of chronic addictions, others have shown a blunted responsivity at brain reward sites with food, nicotine, and even gambling behavior. Finally, we are cognizant of the differences in dopaminergic function as addiction progresses and argue that relapse may be tied to dopamine deficiency

  12. Testing Dietary Hypotheses of East African Hominines Using Buccal Dental Microwear Data.

    Science.gov (United States)

    Martínez, Laura Mónica; Estebaranz-Sánchez, Ferran; Galbany, Jordi; Pérez-Pérez, Alejandro

    2016-01-01

    There is much debate on the dietary adaptations of the robust hominin lineages during the Pliocene-Pleistocene transition. It has been argued that the shift from C3 to C4 ecosystems in Africa was the main factor responsible for the robust dental and facial anatomical adaptations of Paranthropus taxa, which might be indicative of the consumption of fibrous, abrasive plant foods in open environments. However, occlusal dental microwear data fail to provide evidence of such dietary adaptations and are not consistent with isotopic evidence that supports greater C4 food intake for the robust clades than for the gracile australopithecines. We provide evidence from buccal dental microwear data that supports softer dietary habits than expected for P. aethiopicus and P. boisei based both on masticatory apomorphies and isotopic analyses. On one hand, striation densities on the buccal enamel surfaces of paranthropines teeth are low, resembling those of H. habilis and clearly differing from those observed on H. ergaster, which display higher scratch densities indicative of the consumption of a wide assortment of highly abrasive foodstuffs. Buccal dental microwear patterns are consistent with those previously described for occlusal enamel surfaces, suggesting that Paranthropus consumed much softer diets than previously presumed and thus calling into question a strict interpretation of isotopic evidence. On the other hand, the significantly high buccal scratch densities observed in the H. ergaster specimens are not consistent with a highly specialized, mostly carnivorous diet; instead, they support the consumption of a wide range of highly abrasive food items.

  13. Testing Dietary Hypotheses of East African Hominines Using Buccal Dental Microwear Data.

    Directory of Open Access Journals (Sweden)

    Laura Mónica Martínez

    Full Text Available There is much debate on the dietary adaptations of the robust hominin lineages during the Pliocene-Pleistocene transition. It has been argued that the shift from C3 to C4 ecosystems in Africa was the main factor responsible for the robust dental and facial anatomical adaptations of Paranthropus taxa, which might be indicative of the consumption of fibrous, abrasive plant foods in open environments. However, occlusal dental microwear data fail to provide evidence of such dietary adaptations and are not consistent with isotopic evidence that supports greater C4 food intake for the robust clades than for the gracile australopithecines. We provide evidence from buccal dental microwear data that supports softer dietary habits than expected for P. aethiopicus and P. boisei based both on masticatory apomorphies and isotopic analyses. On one hand, striation densities on the buccal enamel surfaces of paranthropines teeth are low, resembling those of H. habilis and clearly differing from those observed on H. ergaster, which display higher scratch densities indicative of the consumption of a wide assortment of highly abrasive foodstuffs. Buccal dental microwear patterns are consistent with those previously described for occlusal enamel surfaces, suggesting that Paranthropus consumed much softer diets than previously presumed and thus calling into question a strict interpretation of isotopic evidence. On the other hand, the significantly high buccal scratch densities observed in the H. ergaster specimens are not consistent with a highly specialized, mostly carnivorous diet; instead, they support the consumption of a wide range of highly abrasive food items.

  14. Adolescents previously involved in Satanism experiencing mental health problems

    Directory of Open Access Journals (Sweden)

    H Heathcote

    1999-09-01

    Full Text Available No research has previously been done regarding the phenomenon of adolescents who have previously been involved in Satanism and who experience obstacles in their strive for mental health. Adolescents previously involved in Satanism present behavioral problems like aggressive outbursts, depression, “ psychosis” or suicide attempts, that could lead to suicide. In the phenomenonanalysis semi-structured, phenomenological interviews were performed with the respondents and their parents. The respondents were requested to write a naïve sketch about their life. After completion of the data-control, guidelines for nursing staff were set.

  15. Influence of previous participation in physical activity on its ...

    African Journals Online (AJOL)

    ... participation can influence perceptions of PA among the students. Physical activity promotion programmes should consider the role of these factors which should be emphasised from childhood. Keywords: physical activity, students, perceived benefits, perceived barriers, previous participation, sedentary lifestyle, Rwanda

  16. Choice of contraception after previous operative delivery at a family ...

    African Journals Online (AJOL)

    Choice of contraception after previous operative delivery at a family planning clinic in Northern Nigeria. Amina Mohammed‑Durosinlorun, Joel Adze, Stephen Bature, Caleb Mohammed, Matthew Taingson, Amina Abubakar, Austin Ojabo, Lydia Airede ...

  17. Payload specialist Reinhard Furrer show evidence of previous blood sampling

    Science.gov (United States)

    1985-01-01

    Payload specialist Reinhard Furrer shows evidence of previous blood sampling while Wubbo J. Ockels, Dutch payload specialist (only partially visible), extends his right arm after a sample has been taken. Both men show bruises on their arms.

  18. Delivery outcomes at term after one previous cesarean section.

    Science.gov (United States)

    Yamani-Zamzami, Tarik Y

    2007-12-01

    To determine the maternal and perinatal outcomes at term in women with one previous cesarean delivery and with no history of vaginal birth. This is a case-control study conducted at King Abdul-Aziz University Hospital, Jeddah, Kingdom of Saudi Arabia, between January 1, 1999 and December 31, 2002. One hundred sixty-two women with one previous cesarean delivery and with no previous vaginal birth were compared with 324 control women. The cesarean section rate was higher in the study group 40 (24.7%) versus 23 (7.1%) in the control group and was statistically significant (phistory of vaginal delivery are considered less favorable, the vaginal birth after cesarean section success rate may be even lower if the indication for previous primary cesarean delivery was failure to progress, and may be associated with increased risk of uterine rupture. Further study is required to confirm our findings.

  19. [Influence of previous abdominopelvic surgery on gynecological laparoscopic operation].

    Science.gov (United States)

    Jin, Haoran; Shi, Wei; Zhou, Yingfang; Wu, Beisheng; Peng, Chao

    2014-09-01

    To investigate the influence of previous abdominopelvic surgery on gynecological laparoscopic operation. A retrospective analysis of 3 283 cases of gynecological diseases by laparoscopic operation patients in Peking University First Hospital from 2007 January to 2012 December, among them, 719 (21.90%) patients with previous abdominopelvic surgery history (study Group), 2 564 (78.10%)patients have no history of abdominopelvic surgery (control group). Study group 719 patients, previous operation times: one time in 525 cases, 194 cases were multiple; previous operation: 185 cases of gynecological surgery, 305 cases of obstetric surgery, 108 cases of general surgery, and 121 complex surgery (include at least two kinds of surgery); previous operative approach: 650 cases laparotomy and 69 cases laparoscopy. Compared two groups of patients with abdominopelvic adhesion and the gynecologic laparoscopic operation situation, analyzed the influence of previous abdominopelvic surgery on abdominopelvic adhesion on and gynecological laparoscopic operation. The incidence of abdominopelvic adhesion in the patients with previous abdominopelvic surgery was 51.2% (368/719), which was significantly higher than that of 8.2% (211/2 564)in patients without previous abdominopelvic surgery (P surgery (23.1%, 166/719) was significantly higher than that in the control group (3.3% , 85/2 564;P laparotomy was 0.6% (4/719) significantly more than the control groups (0.1%, 2/2 564; P = 0.023). Compared with other groups, patients with gynecological or complex surgery or multiple operation history presented more severe abdominopelvic adhesion both in the score and degree (P laparotomy showed no statistical difference between the two groups (P > 0.05). The laparoscopic operation could be carried out successfully and safely in patients with a history of various abdominopelvic operations, but the conversion rate increases, for patients with a history of multiple operation because of pelvic adhesion

  20. Differences between previously married and never married 'gay' men: family background, childhood experiences and current attitudes.

    Science.gov (United States)

    Higgins, Daryl J

    2004-01-01

    Despite a large body of literature on the development of sexual orientation, little is known about why some gay men have been (or remain) married to a woman. In the current study, a self-selected sample of 43 never married gay men ('never married') and 26 gay men who were married to a woman ('previously married') completed a self-report questionnaire. Hypotheses were based on five possible explanations for gay men's marriages: (a) differences in sexual orientation (i.e., bisexuality); (b) internalized homophobia; (c) religious intolerance; (d) confusion created because of childhood/adolescent sexual experiences; and/or (e) poor psychological adjustment. Previously married described their families' religious beliefs as more fundamentalist than never married. No differences were found between married' and never married' ratings of their sexual orientation and identity, and levels of homophobia and self-depreciation. Family adaptability and family cohesion and the degree to which respondents reported having experienced child maltreatment did not distinguish between previously married and never married. The results highlight how little is understood of the reasons why gay men marry, and the need to develop an adequate theoretical model.

  1. The recent similarity hypotheses to describe water infiltration into homogeneous soils

    Directory of Open Access Journals (Sweden)

    Klaus Reichardt

    2016-08-01

    Full Text Available ABSTRACT A similarity hypothesis recently presented to describe horizontal infiltration into homogeneous soils, developed for coarse-textured soils like sieved marine sand, implies that the soil water retention function θ(h is the mirror image of an extended Boltzmann transform function θ(λ2. A second hypothesis applicable to vertical infiltration suggests that the soil water retention function θ(h is also the mirror image of the soil water profile θ(z. Using previously published infiltration data, we investigated whether these two similarity solutions successfully describe infiltration into two “normal” soils. Although the theory using the first similarity assumption adequately describes horizontal cumulative infiltration and infiltration rate into both soils, it fails to estimate soil water distributions measured between soil profiles. The second similarity solution for vertical infiltration into either soil completely fails to coincide with measured soil water distributions, cumulative infiltration and infiltration rate.

  2. On the Wrong Key Randomisation and Key Equivalence Hypotheses in Matsui’s Algorithm 2

    DEFF Research Database (Denmark)

    Bogdanov, Andrey; Tischhauser, Elmar

    2014-01-01

    estimates. Our study suggests that the efficiency of Matsui’s Algorithm 2 has been previously somewhat overestimated in the cases where the adversary attempts to use a linear approximation with a low bias, to attain a high computational advantage over brute force, or both. These cases are typical since...... needs adjustment. We show that it systematically neglects the varying bias for wrong keys. Based on that, we propose an adjusted statistical model and derive more accurate estimates for the success probability and data complexity of linear attacks which are demonstrated to deviate from all known...... cryptanalysts always try to break as many rounds of the cipher as possible by pushing the attack to its limit. Surprisingly, our approach also reveals the fact that the success probability is not a monotonously increasing function of the data complexity, and can decrease if more data is used. Using less data...

  3. Secondary recurrent miscarriage is associated with previous male birth.

    LENUS (Irish Health Repository)

    Ooi, Poh Veh

    2011-01-01

    Secondary recurrent miscarriage (RM) is defined as three or more consecutive pregnancy losses after delivery of a viable infant. Previous reports suggest that a firstborn male child is associated with less favourable subsequent reproductive potential, possibly due to maternal immunisation against male-specific minor histocompatibility antigens. In a retrospective cohort study of 85 cases of secondary RM we aimed to determine if secondary RM was associated with (i) gender of previous child, maternal age, or duration of miscarriage history, and (ii) increased risk of pregnancy complications. Fifty-three women (62.0%; 53\\/85) gave birth to a male child prior to RM compared to 32 (38.0%; 32\\/85) who gave birth to a female child (p=0.002). The majority (91.7%; 78\\/85) had uncomplicated, term deliveries and normal birth weight neonates, with one quarter of the women previously delivered by Caesarean section. All had routine RM investigations and 19.0% (16\\/85) had an abnormal result. Fifty-seven women conceived again and 33.3% (19\\/57) miscarried, but there was no significant difference in failure rates between those with a previous male or female child (13\\/32 vs. 6\\/25, p=0.2). When patients with abnormal results were excluded, or when women with only one previous child were considered, there was still no difference in these rates. A previous male birth may be associated with an increased risk of secondary RM but numbers preclude concluding whether this increases recurrence risk. The suggested association with previous male birth provides a basis for further investigations at a molecular level.

  4. Secondary recurrent miscarriage is associated with previous male birth.

    LENUS (Irish Health Repository)

    Ooi, Poh Veh

    2012-01-31

    Secondary recurrent miscarriage (RM) is defined as three or more consecutive pregnancy losses after delivery of a viable infant. Previous reports suggest that a firstborn male child is associated with less favourable subsequent reproductive potential, possibly due to maternal immunisation against male-specific minor histocompatibility antigens. In a retrospective cohort study of 85 cases of secondary RM we aimed to determine if secondary RM was associated with (i) gender of previous child, maternal age, or duration of miscarriage history, and (ii) increased risk of pregnancy complications. Fifty-three women (62.0%; 53\\/85) gave birth to a male child prior to RM compared to 32 (38.0%; 32\\/85) who gave birth to a female child (p=0.002). The majority (91.7%; 78\\/85) had uncomplicated, term deliveries and normal birth weight neonates, with one quarter of the women previously delivered by Caesarean section. All had routine RM investigations and 19.0% (16\\/85) had an abnormal result. Fifty-seven women conceived again and 33.3% (19\\/57) miscarried, but there was no significant difference in failure rates between those with a previous male or female child (13\\/32 vs. 6\\/25, p=0.2). When patients with abnormal results were excluded, or when women with only one previous child were considered, there was still no difference in these rates. A previous male birth may be associated with an increased risk of secondary RM but numbers preclude concluding whether this increases recurrence risk. The suggested association with previous male birth provides a basis for further investigations at a molecular level.

  5. Why biogeographical hypotheses need a well supported phylogenetic framework: a conceptual evaluation

    Directory of Open Access Journals (Sweden)

    Charles Morphy D. Santos

    2007-01-01

    Full Text Available A growing number of biogeographical methods have attempted to describe formal means of reconstructing the biogeographical history of the organisms. Whatever the biogeographical method, however, the source of systematic information has to be well worked out. Taxonomic noise is sometimes a true impediment to properly deal with the complexity of life in its three-dimensional aspects, the threefold parallelism represented by form, space and time. This paper argues that historical systematics is a necessary basis for a historical biogeography. Organismal phylogenies or at least hypotheses of monophyly should be taken as the basis for the study of distribution patterns. Whenever a non-monophyletic taxon is misleadingly taken as monophyletic, erroneous interpretations in evolutionary analyses necessarily follow. When the proportion of paraphyletic taxa considered in an analysis is small, a general pattern may be obtained, but the interpretation of the biogeographical evolution of each paraphyletic taxon will be equivocated. The delimitation of areas of endemism also depends on the precision of the recovered phylogenetic information. Indices based on phylogenetic diversity allow the delimitation of areas for conservation of biological diversity. Despite the plethora of current available biogeographical methods, biogeography is not a mess, as was pointed elsewhere. The order in the discipline is subtle: as biogeography intends to comprehend the living world based on the study of the form, space and time, a phylogenetic framework is a basic requirement. The lack of reliable biogeographical primary information - historical taxa - certainly creates severe obstacles for historical biogeography.Um crescente número de métodos biogeográficos tem buscado descrever maneiras formais de reconstruir a história biogeográfica dos organismos. Entretanto, para qualquer método biogeográfico empregado, a fonte de informação sistemática deve ser precisa. Ru

  6. 2 CFR 225.45 - Relationship to previous issuance.

    Science.gov (United States)

    2010-01-01

    ... 2 Grants and Agreements 1 2010-01-01 2010-01-01 false Relationship to previous issuance. 225.45 Section 225.45 Grants and Agreements OFFICE OF MANAGEMENT AND BUDGET CIRCULARS AND GUIDANCE Reserved COST PRINCIPLES FOR STATE, LOCAL, AND INDIAN TRIBAL GOVERNMENTS (OMB CIRCULAR A-87) § 225.45 Relationship to...

  7. Cryptococcal meningitis in a previously healthy child | Chimowa ...

    African Journals Online (AJOL)

    An 8-year-old previously healthy female presented with a 3 weeks history of headache, neck stiffness, deafness, fever and vomiting and was diagnosed with cryptococcal meningitis. She had documented hearing loss and was referred to tertiary-level care after treatment with fluconazole did not improve her neurological ...

  8. Rapid fish stock depletion in previously unexploited seamounts: the ...

    African Journals Online (AJOL)

    Rapid fish stock depletion in previously unexploited seamounts: the case of Beryx splendens from the Sierra Leone Rise (Gulf of Guinea) ... A spectral analysis and red-noise spectra procedure (REDFIT) algorithm was used to identify the red-noise spectrum from the gaps in the observed time-series of catch per unit effort by ...

  9. Obstructive pulmonary disease in patients with previous tuberculosis ...

    African Journals Online (AJOL)

    Obstructive pulmonary disease in patients with previous tuberculosis: Pathophysiology of a community-based cohort. B.W. Allwood, R Gillespie, M Galperin-Aizenberg, M Bateman, H Olckers, L Taborda-Barata, G.L. Calligaro, Q Said-Hartley, R van Zyl-Smit, C.B. Cooper, E van Rikxoort, J Goldin, N Beyers, E.D. Bateman ...

  10. Balance and bilateral skills of selected previously disadvantaged ...

    African Journals Online (AJOL)

    Balance and bilateral skills of selected previously disadvantaged children aged 9 to 12 years. Eileen K Africa, Karel J Van Deventer. Abstract. The main aim of the study was to design an appropriate motor skills development programme that could be implemented in any primary school to improve the fundamental motor ...

  11. Outcome Of Pregnancy Following A Previous Lower Segment ...

    African Journals Online (AJOL)

    Background: A previous ceasarean section is an important variable that influences patient management in subsequent pregnancies. A trial of vaginal delivery in such patients is a feasible alternative to a secondary section, thus aiding to reduce the ceasarean section rate and its associated co-morbidities. Objective: To ...

  12. Suburethral sling procedures after previous surgery for urinary ...

    African Journals Online (AJOL)

    Objective. To compare the outcome of suburethral sling procedures (tension-free vaginal tape (TVT), obturator tape (Ob-tape)) for stress urinary incontinence (SUI) in women with previous surgery for SUI or pelvic organ prolapse (POP). Methods. A comparative, descriptive, retrospective study was done using information ...

  13. 5 CFR 532.405 - Use of highest previous rate.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Use of highest previous rate. 532.405 Section 532.405 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS... rate may be based upon a rate of pay received during a temporary promotion, so long as the temporary...

  14. 24 CFR 1710.552 - Previously accepted state filings.

    Science.gov (United States)

    2010-04-01

    ... of Substantially Equivalent State Law § 1710.552 Previously accepted state filings. (a) Materials... and contracts or agreements contain notice of purchaser's revocation rights. In addition see § 1715.15..., unless the developer is obligated to do so in the contract. (b) If any such filing becomes inactive or...

  15. 5 CFR 9701.352 - Use of highest previous rate.

    Science.gov (United States)

    2010-01-01

    ... HUMAN RESOURCES MANAGEMENT SYSTEM Pay and Pay Administration Pay Administration § 9701.352 Use of... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Use of highest previous rate. 9701.352 Section 9701.352 Administrative Personnel DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT...

  16. Bilateral orbital infarction and retinal detachment in a previously ...

    African Journals Online (AJOL)

    In this report, we present a case of an 11‑year‑old previously undiagnosed sickle cell disease Nigerian girl with severe acute bilateral orbital infarction and retinal detachment to highlight that hemoglobinopathy induced orbital infarction should be considered in African children with acute onset proptosis with or without ...

  17. Response to health insurance by previously uninsured rural children.

    Science.gov (United States)

    Tilford, J M; Robbins, J M; Shema, S J; Farmer, F L

    1999-08-01

    To examine the healthcare utilization and costs of previously uninsured rural children. Four years of claims data from a school-based health insurance program located in the Mississippi Delta. All children who were not Medicaid-eligible or were uninsured, were eligible for limited benefits under the program. The 1987 National Medical Expenditure Survey (NMES) was used to compare utilization of services. The study represents a natural experiment in the provision of insurance benefits to a previously uninsured population. Premiums for the claims cost were set with little or no information on expected use of services. Claims from the insurer were used to form a panel data set. Mixed model logistic and linear regressions were estimated to determine the response to insurance for several categories of health services. The use of services increased over time and approached the level of utilization in the NMES. Conditional medical expenditures also increased over time. Actuarial estimates of claims cost greatly exceeded actual claims cost. The provision of a limited medical, dental, and optical benefit package cost approximately $20-$24 per member per month in claims paid. An important uncertainty in providing health insurance to previously uninsured populations is whether a pent-up demand exists for health services. Evidence of a pent-up demand for medical services was not supported in this study of rural school-age children. States considering partnerships with private insurers to implement the State Children's Health Insurance Program could lower premium costs by assembling basic data on previously uninsured children.

  18. The effect of previous traumatic injury on homicide risk.

    Science.gov (United States)

    Griffin, Russell L; Davis, Gregory G; Levitan, Emily B; MacLennan, Paul A; Redden, David T; McGwin, Gerald

    2014-07-01

    Research has reported that a strong risk factor for traumatic injury is having a previous injury (i.e., recidivism). To date, the only study examining the relationship between recidivism and homicide reported strong associations, but was limited by possible selection bias. The current matched case-control study utilized coroner's data from 2004 to 2008. Subjects were linked to trauma registry data to determine whether the person had a previous traumatic injury. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) for the association between homicide and recidivism. Homicide risk was increased for those having a previous traumatic injury (OR 1.81, 95% CI 1.09-2.99) or a previous intentional injury (OR 2.53, 95% CI 1.24-5.17). These results suggest an association between homicide and injury recidivism, and that trauma centers may be an effective setting for screening individuals for secondary prevention efforts of homicide through violence prevention programs. © 2014 American Academy of Forensic Sciences.

  19. Control of feed intake as affected by previous treatment | Pienaar ...

    African Journals Online (AJOL)

    An experiment was conducted with eighteen rumen cannulated sheep fed on a chopped lucerne diet. Previous level of intake significantly influenced the level at which sheep initially established voluntary feed intake. This difference had disappeared after three weeks on an ad lib. intake. Perturbation analysis of the results ...

  20. "Battered Women" and Previous Victimization: Is the Question Relevant?

    Science.gov (United States)

    Gudim, Laurie, Comp.; And Others

    This report discusses battered women and the role of their previous victimization. After a literature review on family violence in general, these topics are discussed: (1) family violence and the patriarchy; (2) the historical background of family violence; (3) intergenerational cycle of violence; and (4) psychological literature's four ways…

  1. Choice of contraception after previous operative delivery at a family ...

    African Journals Online (AJOL)

    Age, education, religion, parity, prior contraception, and interval from the last delivery were significantly associated with the current choice of contraception (P 0.05). Overall, when comparing the pattern among those with a previous operative delivery and those without, ...

  2. Process cells dismantling of EUREX pant: previous activities

    International Nuclear Information System (INIS)

    Gili, M.

    1998-01-01

    In the '98-'99 period some process cells of the EUREX pant will be dismantled, in order to place there the liquid wastes conditioning plant 'CORA'. This report resumes the previous activities (plant rinsing campaigns and inactive Cell 014 dismantling), run in the past three years and the drawn experience [it

  3. The job satisfaction of principals of previously disadvantaged schools

    African Journals Online (AJOL)

    The aim of this study was to identify influences on the job satisfaction of previously disadvantaged school principals in North-West Province. Evans's theory of job satisfaction, morale and motivation was useful as a conceptual framework. A mixedmethods explanatory research design was important in discovering issues with ...

  4. Previous utilization of service does not improve timely booking in ...

    African Journals Online (AJOL)

    Previous utilization of service does not improve timely booking in antenatal care: Cross sectional study on timing of antenatal care booking at public health facilities in ... Methods: A cross sectional study was conducted to collect data from 630 pregnant women who were attending antenatal care service at 10 governmental ...

  5. Research Note Effects of previous cultivation on regeneration of ...

    African Journals Online (AJOL)

    We investigated the effects of previous cultivation on regeneration potential under miombo woodlands in a resettlement area, a spatial product of Zimbabwe's land reforms. We predicted that cultivation would affect population structure, regeneration, recruitment and potential grazing capacity of rangelands. Plant attributes ...

  6. Mondor's Disease of the Breast in a Nigerian Woman Previously ...

    African Journals Online (AJOL)

    2017-09-14

    Sep 14, 2017 ... Case Report. How to cite this article: Olarinoye-Akorede SA, Silas BT. Mondor's disease of the breast in a Nigerian woman previously treated for invasive ductal carcinoma in the ... and the new creations are licensed under the identical terms. For reprints .... malignancy. Financial support and sponsorship.

  7. 44 CFR 402.5 - Forwarding commodities previously shipped.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Forwarding commodities... commodities previously shipped. Order T-1 applies to transportation on or discharge from ships documented... ship or aircraft, before the issuance of Order T-1, had transported restricted commodities manifested...

  8. Reoperative sentinel lymph node biopsy after previous mastectomy.

    Science.gov (United States)

    Karam, Amer; Stempel, Michelle; Cody, Hiram S; Port, Elisa R

    2008-10-01

    Sentinel lymph node (SLN) biopsy is the standard of care for axillary staging in breast cancer, but many clinical scenarios questioning the validity of SLN biopsy remain. Here we describe our experience with reoperative-SLN (re-SLN) biopsy after previous mastectomy. Review of the SLN database from September 1996 to December 2007 yielded 20 procedures done in the setting of previous mastectomy. SLN biopsy was performed using radioisotope with or without blue dye injection superior to the mastectomy incision, in the skin flap in all patients. In 17 of 20 patients (85%), re-SLN biopsy was performed for local or regional recurrence after mastectomy. Re-SLN biopsy was successful in 13 of 20 patients (65%) after previous mastectomy. Of the 13 patients, 2 had positive re-SLN, and completion axillary dissection was performed, with 1 having additional positive nodes. In the 11 patients with negative re-SLN, 2 patients underwent completion axillary dissection demonstrating additional negative nodes. One patient with a negative re-SLN experienced chest wall recurrence combined with axillary recurrence 11 months after re-SLN biopsy. All others remained free of local or axillary recurrence. Re-SLN biopsy was unsuccessful in 7 of 20 patients (35%). In three of seven patients, axillary dissection was performed, yielding positive nodes in two of the three. The remaining four of seven patients all had previous modified radical mastectomy, so underwent no additional axillary surgery. In this small series, re-SLN was successful after previous mastectomy, and this procedure may play some role when axillary staging is warranted after mastectomy.

  9. Coopersmith Self-Esteem: Two Different Hypothesized Factor Models--Both Acceptable for the Same Data Structure.

    Science.gov (United States)

    Hofmann, Rich; Sherman, Larry

    Using data from 135 sixth-, seventh-, and eighth-graders between 11 and 15 years old attending a middle school in a suburban Southwest Ohio school district, two hypothesized models of the factor structures for the Coopersmith Self-Esteem Inventory were tested. One model represents the original Coopersmith factor structure, and the other model is…

  10. Bovid mortality profiles in paleoecological context falsify hypotheses of endurance running-hunting and passive scavenging by early Pleistocene hominins

    Science.gov (United States)

    Bunn, Henry T.; Pickering, Travis Rayne

    2010-11-01

    The world's first archaeological traces from 2.6 million years ago (Ma) at Gona, in Ethiopia, include sharp-edged cutting tools and cut-marked animal bones, which indicate consumption of skeletal muscle by early hominin butchers. From that point, evidence of hominin meat-eating becomes increasingly more common throughout the Pleistocene archaeological record. Thus, the substantive debate about hominin meat-eating now centers on mode(s) of carcass resource acquisition. Two prominent hypotheses suggest, alternatively, (1) that early Homo hunted ungulate prey by running them to physiological failure and then dispatching them, or (2) that early Homo was relegated to passively scavenging carcass residues abandoned by carnivore predators. Various paleontologically testable predictions can be formulated for both hypotheses. Here we test four predictions concerning age-frequency distributions for bovids that contributed carcass remains to the 1.8 Ma. old FLK 22 Zinjanthropus (FLK Zinj, Olduvai Gorge, Tanzania) fauna, which zooarchaeological and taphonomic data indicate was formed predominantly by early Homo. In all but one case, the bovid mortality data from FLK Zinj violate test predictions of the endurance running-hunting and passive scavenging hypotheses. When combined with other taphonomic data, these results falsify both hypotheses, and lead to the hypothesis that early Homo operated successfully as an ambush predator.

  11. Teaching the Fluctuation Test "In Silico" by Using Mutate: A Program to Distinguish between the Adaptive and Spontaneous Mutation Hypotheses

    Science.gov (United States)

    Carvajal-Rodriguez, Antonio

    2012-01-01

    Mutate is a program developed for teaching purposes to impart a virtual laboratory class for undergraduate students of Genetics in Biology. The program emulates the so-called fluctuation test whose aim is to distinguish between spontaneous and adaptive mutation hypotheses in bacteria. The plan is to train students in certain key multidisciplinary…

  12. Testing Informative Hypotheses in SEM Increases Power: An Illustration Contrasting Classical Hypothesis Testing with a Parametric Bootstrap Approach

    Science.gov (United States)

    van de Schoot, Rens; Strohmeier, Dagmar

    2011-01-01

    In the present paper, the application of a parametric bootstrap procedure, as described by van de Schoot, Hoijtink, and Dekovic (2010), will be applied to demonstrate that a direct test of an informative hypothesis offers more informative results compared to testing traditional null hypotheses against catch-all rivals. Also, more power can be…

  13. The RNA-world and co-evolution hypotheses and the origin of life: Implications, research strategies and perspectives

    Science.gov (United States)

    Lahav, Noam

    1993-12-01

    The applicability of the RNA-world and co-evolution hypotheses to the study of the very first stages of the origin of life is discussed. The discussion focuses on the basic differences between the two hypotheses and their implications, with regard to the reconstruction methodology, ribosome emergence, balance between ribozymes and protein enzymes, and their major difficulties. Additional complexities of the two hypotheses, such as membranes and the energy source of the first reactions, are not treated in the present work. A central element in the proposed experimental strategies is the study of the catalytic activities of very small peptides and RNA-like oligomers, according to existing, as well as to yet-to-be-invented scenarios of the two hypotheses under consideration. It is suggested that the noveldirected molecular evolution technology, andmolecular computational modeling, can be applied to this research. This strategy is assumed to be essential for the suggested goal of future studies of the origin of life, namely, the establishment of a ‘Primordial Darwinian entity’.

  14. Four Hypotheses to Explain Axillary Budbreak after Removal of Flower Shoots in a Cut-rose Crop

    NARCIS (Netherlands)

    Wubs-Timmermans, A.M.; Heuvelink, E.; Marcelis, L.F.M.; Okello, R.C.; Buck-Sorlin, G.H.; Vos, J.

    2013-01-01

    When flower-bearing shoots in cut-rose (Rosa ×hybrida) are harvested (removed), a varying number of repressed axillary buds on the shoot remainder start to grow into new shoots (budbreak). Besides removing within-shoot correlative inhibition, it is hypothesized that shoot removal leads to 1)

  15. On the use of three hydrological models as hypotheses to investigate the behaviour of a small Mediterranean catchment

    Science.gov (United States)

    Ruiz Pérez, Guiomar; Latron, Jérôme; Llorens, Pilar; Gallart, Francesc; Francés, Félix

    2017-04-01

    Selecting an adequate hydrological model is the first step to carry out a rainfall-runoff modelling exercise. A hydrological model is a hypothesis of catchment functioning, encompassing a description of dominant hydrological processes and predicting how these processes interact to produce the catchment's response to external forcing. Current research lines emphasize the importance of multiple working hypotheses for hydrological modelling instead of only using a single model. In line with this philosophy, here different hypotheses were considered and analysed to simulate the nonlinear response of a small Mediterranean catchment and to progress in the analysis of its hydrological behaviour. In particular, three hydrological models were considered representing different potential hypotheses: two lumped models called LU3 and LU4, and one distributed model called TETIS. To determine how well each specific model performed and to assess whether a model was more adequate than another, we raised three complementary tests: one based on the analysis of residual errors series, another based on a sensitivity analysis and the last one based on using multiple evaluation criteria associated to the concept of Pareto frontier. This modelling approach, based on multiple working hypotheses, helped to improve our perceptual model of the catchment behaviour and, furthermore, could be used as a guidance to improve the performance of other environmental models.

  16. Genesis Hypotheses Concerning Putative Rootless Cone Groups in Isidis Planitia, Mars

    Science.gov (United States)

    Pithawala, T. M.; Ghent, R. R.

    2008-09-01

    ABSTRACT Introduction Isidis Planitia is one of the many areas on Mars containing thumbprint terrain (TPT), a term coined to reflect the resemblance in Viking images to fingerprints. Other instances occur in Argyre, Hellas, Arcadia Planitia, and Utopia Planitia. The terrain is found where Greeley and Guest (1987) have defined the Hesperian Ridged Plains (Hvr) unit. However, landforms comprising the TPT in Isidis are markedly different in morphology from those in the northern plains. The purpose of this study is to conduct a systematic examination of the TPT in Isidis Planitia using high-resolution imagery, and to propose a hypothesis for its genesis. Northern Plains TPT Morphology: TPT landforms include branching troughs and medial ridges forming whorled lobes and mounds, most with basal scarps or terraces. TPT has been described as consisting of parallel, en echelon, or nested sets of regularly spaced curvilinear ridges or aligned hills [1]. The ridges were estimated to be 0.5-2.5 km wide and 1-40 km long, with a characteristic spacing of 2-6 km. Whorled lobes of TPT are 75-150 km wide, with heights ranging from 10-200 m. Previous work identified 22 areas of TPT, covering 3000- 420,000 km2 in the Northern Plains at elevations between 0 and -2 km. In Utopia, TPT includes branching troughs and medial ridges [5], and TPT is closely associated with troughs in at least 9 other Northern Plains areas [1]. Northern Plains TPT Origin: MOLA topography supports the hypothesis that TPT and associated trough systems in Utopia and Arcadia Planitae are glacial features [1,2,3]. Possible mechanisms include formation of ridges as moraines and troughs as eskers formed by wet-based continental glaciers. The absence of drumlin fields suggests that the glaciers responsible for forming the topography may have been cold-based and thus did not deform the substrate so as to form drumlins [4]. A puzzling characteristic of Mars alleged glacial landscapes is that they are morphologically

  17. Influence of Previous Knowledge, Language Skills and Domain-specific Interest on Observation Competency

    Science.gov (United States)

    Kohlhauf, Lucia; Rutke, Ulrike; Neuhaus, Birgit

    2011-10-01

    Many epoch-making biological discoveries (e.g. Darwinian Theory) were based upon observations. Nevertheless, observation is often regarded as `just looking' rather than a basic scientific skill. As observation is one of the main research methods in biological sciences, it must be considered as an independent research method and systematic practice of this method is necessary. Because observation skills form the basis of further scientific methods (e.g. experiments or comparisons) and children from the age of 4 years are able to independently generate questions and hypotheses, it seems possible to foster observation competency at a preschool level. To be able to provide development-adequate individual fostering of this competency, it is first necessary to assess each child's competency. Therefore, drawing on the recent literature, we developed in this study a competency model that was empirically evaluated within learners ( N = 110) from different age groups, from kindergarten to university. In addition, we collected data on language skills, domain-specific interest and previous knowledge to analyse coherence between these skills and observation competency. The study showed as expected that previous knowledge had a high impact on observation competency, whereas the influence of domain-specific interest was nonexistent. Language skills were shown to have a weak influence. By utilising the empirically validated model consisting of three dimensions (`Describing', `Scientific reasoning' and `Interpreting') and three skill levels, it was possible to assess each child's competency level and to develop and evaluate guided play activities to individually foster a child's observation competency.

  18. Previously unreported abnormalities in Wolfram Syndrome Type 2.

    Science.gov (United States)

    Akturk, Halis Kaan; Yasa, Seda

    2017-01-01

    Wolfram syndrome (WFS) is a rare autosomal recessive disease with non-autoimmune childhood onset insulin dependent diabetes and optic atrophy. WFS type 2 (WFS2) differs from WFS type 1 (WFS1) with upper intestinal ulcers, bleeding tendency and the lack ofdiabetes insipidus. Li-fespan is short due to related comorbidities. Only a few familieshave been reported with this syndrome with the CISD2 mutation. Here we report two siblings with a clinical diagnosis of WFS2, previously misdiagnosed with type 1 diabetes mellitus and diabetic retinopathy-related blindness. We report possible additional clinical and laboratory findings that have not been pre-viously reported, such as asymptomatic hypoparathyroidism, osteomalacia, growth hormone (GH) deficiency and hepatomegaly. Even though not a requirement for the diagnosis of WFS2 currently, our case series confirm hypogonadotropic hypogonadism to be also a feature of this syndrome, as reported before. © Polish Society for Pediatric Endocrinology and Diabetology.

  19. Nicotine Elicits Methamphetamine-Seeking in Rats Previously Administered Nicotine

    OpenAIRE

    Neugebauer, N. M.; Harrod, S. B.; Bardo, M. T.

    2009-01-01

    Research has indicated a high correlation between psychostimulant use and tobacco cigarette smoking in human substance abusers. The objective of the current study was to examine the effects of acute and repeated nicotine administration on responding for intravenous methamphetamine (0.03 mg/kg/infusion) in a rodent model of self-administration, as well as the potential of nicotine to induce reinstatement of previously extinguished drug-taking behavior in male Sprague-Dawley rats. In addition, ...

  20. Previous climatic alterations are caused by the sun

    International Nuclear Information System (INIS)

    Groenaas, Sigbjoern

    2003-01-01

    The article surveys the scientific results of previous research into the contribution of the sun to climatic alterations. The author concludes that there is evidence of eight cold periods after the last ice age and that the alterations largely were due to climate effects from the sun. However, these effects are only causing a fraction of the registered global warming. It is assumed that the human activities are contributing to the rest of the greenhouse effect

  1. Event Sequence Variability in Healthy Swallowing: Building on Previous Findings

    OpenAIRE

    Molfenter, Sonja M.; Leigh, Chelsea; Steele, Catriona M.

    2014-01-01

    This study builds on previous work by Kendall, Leonard and McKenzie, which investigated event sequence variability for 12 paired-events during swallowing by healthy volunteers. They identified four event pairs, which always occurred in a stereotyped order as well as a most-common occurring overall order of events during swallowing. In the current study, we investigate overall event sequencing and the same four paired-events in a sample of swallows by healthy, young (under 45 years old) volunt...

  2. Prevalence and significance of previously undiagnosed rheumatic diseases in pregnancy.

    Science.gov (United States)

    Spinillo, Arsenio; Beneventi, Fausta; Ramoni, Véronique; Caporali, Roberto; Locatelli, Elena; Simonetta, Margherita; Cavagnoli, Chiara; Alpini, Claudia; Albonico, Giulia; Prisco, Elena; Montecucco, Carlomaurizio

    2012-06-01

    The objective of this study was to evaluate the rates of previously undiagnosed rheumatic diseases during the first trimester of pregnancy and their impact on the pregnancy outcome. Pregnant women in their first trimester were screened using a two-step approach using a self-administered 10-item questionnaire and subsequent testing for rheumatic autoantibodies (antinuclear antibody, anti-double-stranded DNA, anti-extractable nuclear antigen, anticardiolipin antibodies, anti-β2-glycoprotein I antibodies and lupus anticoagulant) and evaluation by a rheumatologist. Overall, the complications of pregnancy evaluated included fetal loss, pre-eclampsia, gestational diabetes, fetal growth restriction, delivery at less than 34 weeks, neonatal resuscitation and admission to the neonatal intensive care unit. Out of the 2458 women screened, the authors identified 62 (2.5%) women with previously undiagnosed undifferentiated connective tissue disease (UCTD) and 24 (0.98%) women with previously undiagnosed definite systemic rheumatic disease. The prevalences were seven (0.28%) for systemic lupus erythematosus and Sjogren's syndrome, six (0.24%) for rheumatoid arthritis, three (0.12%) for antiphospholipid syndrome and one (0.04%) for systemic sclerosis. In multiple exact logistic regression, after adjustment for potential confounders, the OR of overall complications of pregnancy were 2.81 (95% CI 1.29 to 6.18) in women with UCTD and 4.57 (95% CI 1.57 to 13.57) in those with definite diseases, respectively, compared with asymptomatic controls. In our population approximately 2.5% and 1% of first trimester pregnant women had a previously undiagnosed UCTD and definite systemic rheumatic disease, respectively. These conditions were associated with significant negative effects on the outcome of pregnancy.

  3. Previously infertile couples and the newborn intensive care unit.

    Science.gov (United States)

    Lind, R F; Pruitt, R L; Greenfeld, D

    1989-05-01

    Having a newborn child admitted to a newborn intensive care unit can be a traumatic experience for parents; however, parents who previously have been infertile face unique problems in coping with this situation. The authors discuss the difficulties parents must overcome in resolving their crises and in developing a good relationship with their child, or, in some cases, coming to terms with the child's death or ongoing disability. In addition, the authors offer suggestions for effective social work intervention.

  4. Antenatal diagnosis of Patau syndrome with previous anomalous baby

    OpenAIRE

    Keerthi Kocherla; Vasantha Kocherla

    2014-01-01

    Patau syndrome is the least common and most severe of the viable autosomal trisomies with median survival of fewer than 3 days was first identified as a cytogenetic syndrome in 1960. Patau syndrome is caused by an extra copy of chromosome 13. In this case report, we present antenatal imaging findings and gross foetal specimen correlation of foetus with Patau syndrome confirmed by karyotyping in third gravida who had significant previous obstetric history of gastrochisis in monochorionic and...

  5. Event sequence variability in healthy swallowing: building on previous findings.

    Science.gov (United States)

    Molfenter, Sonja M; Leigh, Chelsea; Steele, Catriona M

    2014-04-01

    This study builds on previous work by Kendall, Leonard, and McKenzie, which investigated event sequence variability for 12 paired events during swallowing by healthy volunteers. They identified four event pairs that always occurred in a stereotyped order and a most common occurring overall order of events during swallowing. In the current study, we investigated overall event sequencing and the same four paired events in a sample of swallows by healthy young (under 45 years old) volunteers. Data were collected during a 16-swallow lateral videofluoroscopy protocol, which included manipulations of bolus volume, barium density, bolus viscosity, and swallow cueing. Our results agreed with previous findings that variable event sequencing is found in healthy swallowing, and, in regard to obligatory sequencing of two paired events, movement of the arytenoids toward the base of the epiglottis begins prior to upper esophageal sphincter (UES) opening and maximum hyolaryngeal approximation occurs after UES opening. However, our data failed to replicate the previous findings that there is obligatory sequencing of maximum pharyngeal constriction after maximal UES distension and the UES opens before bolus arrival at the UES. The most common observed overall event sequence reported by Kendall et al. was observed in only 4/293 swallows in our dataset. Manipulations of bolus volume, bolus viscosity, barium concentration, swallow cueing, and swallow repetitions could not completely account for the differences observed between the two studies.

  6. Prevalence of Infraumbilical Adhesions in Women With Previous Laparoscopy

    Science.gov (United States)

    Ku, Lowell; Wong, Herb; Liu, C. Y.; Phelps, John Y.

    2007-01-01

    Background and Objectives: The aim of this study is to evaluate the prevalence of intraabdominal adhesions to the umbilicus following gynecologic laparoscopy through an umbilical incision. Methods: A retrospective review was performed of all gynecologic laparoscopic procedures in a private practice setting to identify patients with a repeat laparoscopy who had a history of a previous laparoscopy through an umbilical incision. Patients with a history of other surgeries were excluded. All repeat laparoscopies used a left upper quadrant entry technique where the abdominal cavity was surveyed for adhesions. We also reviewed adverse events attributable to the left upper quadrant entry approach. Results: We identified 151 patients who underwent a second laparoscopy and had a previous umbilical scar. Thirty-two of the 151 (21.2%) patients with a history of a laparoscopy had evidence of adhesions to the umbilical undersurface. No adverse events or injuries were attributed to the left upper quadrant entry technique. Conclusions: Adhesions to the umbilical undersurface occur in 21.2% of patients who have undergone a prior laparoscopy through an umbilical incision. For this reason, we recommend an alternate location for entry in patients with an umbilical scar from a previous laparoscopy. PMID:17651555

  7. Submarine geomorphology of the Celtic Sea - new observations and hypotheses for the glaciation of a mid-latitude continental shelf

    Science.gov (United States)

    Praeg, Daniel; McCarron, Stephen; Dove, Dayton; Cofaigh, Colm Ó.; Monteys, Xavier; Coxon, Peter; Accettella, Daniella; Cova, Andrea; Facchin, Lorenzo; Romeo, Roberto; Scott, Gill

    2015-04-01

    The southern limit of glaciation of the European continental margin lies in the Celtic Sea, where the full extent and dynamics of the British-Irish Ice Sheet (BIIS) remain in question. This is in part because the broad continental shelf contains no obvious glacial geomorphological features, but is dominated by a system of shelf-crossing sediment ridges, up to 60 m high, 10 km wide and 300 km long, traditionally interpreted as moribund palaeo-tidal sand banks. Ice sheet extent has been constrained by samples of subglacial and glacimarine sediments recovered (in the 1970s) between the ridges, and in places on their flanks, used to propose a tidewater ice margin that advanced to a grounding line on the mid-shelf, overriding a precursor ridge system. New information on the glaciation of the Celtic Sea is available from geophysical and core data acquired during Italian- and Irish-led campaigns in 2009, 2012, and 2014, both from the mid- and outer shelf. On the mid-shelf, multibeam seabed imagery of a 25 x 100 km area reveal a distinctive rectilinear network of en echelon ridge segments giving way laterally and longitudinally to transverse ribs. Seismic correlation to glacigenic sediments previously cored on a ridge flank (at core site 49/-09/44) indicates the ribs to be composed in part of glacimarine sediments, above a till reflection that can be traced across the ridge crest. No change in seabed morphology is observed across the proposed grounding line. On the outer shelf, new cores of glacigenic sediments were obtained from the flank of a shelf-crossing ridge, and provide evidence of ice sheet advance to the shelf edge, 150 km beyond the proposed grounding line. The cores from outer Cockburn Bank contain facies interpreted to record subglacial deformation and glacimarine deposition from turbid meltwater plumes during withdrawal of a tidewater ice sheet margin from the shelf edge by 24,265 ± 195 cal BP. These sediments are inferred to form part of a sheet of

  8. Optimization of hydraulic machinery by exploiting previous successful designs

    Energy Technology Data Exchange (ETDEWEB)

    Kyriacou, S A; Giannakoglou, K C [National Technical University of Athens, Parallel CFD and Optimization Unit, PO Box 64069, Athens 15710 (Greece); Weissenberger, S; Grafenberger, P, E-mail: stelios.Kyriacou@gmail.co [Andritz HYDRO, RD, Lunzerstrasse 78, 4031 Linz (Austria)

    2010-08-15

    A design-optimization method for hydraulic machinery is proposed. Optimal designs are obtained using the appropriate CFD evaluation software driven by an evolutionary algorithm which is also assisted by artificial neural networks used as surrogate evaluation models or metamodels. As shown in a previous IAHR paper by the same authors, such an optimization method substantially reduces the CPU cost, since the metamodels can discard numerous non-promising candidate solutions generated during the evolution, at almost negligible CPU cost, without evaluating them by means of the costly CFD tool. The present paper extends the optimization method of the previous paper by making it capable to accommodate and exploit pieces of useful information archived during previous relevant successful designs. So, instead of parameterizing the geometry of the hydraulic machine components, which inevitably leads to many design variables, enough to slow down the design procedure, in the proposed method all new designs are expressed as weighted combinations of the archived ones. The archived designs act as the design space bases. The role of the optimization algorithms is to find the set (or sets, for more than one objectives, where the Pareto front of non-dominated solutions is sought) of weight values, corresponding to the hydraulic machine configuration(s) with optimal performance. Since the number of weights is much less that the number of design variables of the conventional shape parameterization, the design space dimension reduces and the CPU cost of the metamodel-assisted evolutionary algorithm is much lower. The design of a Francis runner is used to demonstrate the capabilities of the proposed method.

  9. Haemophilus influenzae type f meningitis in a previously healthy boy

    DEFF Research Database (Denmark)

    Ronit, Andreas; Berg, Ronan M G; Bruunsgaard, Helle

    2013-01-01

    Non-serotype b strains of Haemophilus influenzae are extremely rare causes of acute bacterial meningitis in immunocompetent individuals. We report a case of acute bacterial meningitis in a 14-year-old boy, who was previously healthy and had been immunised against H influenzae serotype b (Hib......). The causative pathogen was identified as H influenzae serotype f (Hif), and was successfully treated with ceftriaxone. An immunological evaluation revealed transient low levels of immunoglobulins but no apparent immunodeficiency was found 2 years after the clinical insult....

  10. The long-term consequences of previous hyperthyroidism

    DEFF Research Database (Denmark)

    Hjelm Brandt Kristensen, Frans

    2015-01-01

    vascular state. While it is biologically plausible that these changes may induce long-term consequences, the insight into morbidity as well as mortality in patients with previous hyperthyroidism is limited. The reasons for this are a combination of inadequately powered studies, varying definitions......,400 non-hyperthyroid control individuals (matched for age and sex), all identified from a random 5% sample of the Danish background population (n=339,481). In the second study population, 625 same-sex twin pairs, discordant for hyperthyroidism, were included. For each individual, the degree of co...

  11. Cutaneous protothecosis in a patient with previously undiagnosed HIV infection.

    Science.gov (United States)

    Fong, Kenneth; Tee, Shang-Ian; Ho, Madeline S L; Pan, Jiun Yit

    2015-08-01

    Protothecosis is an uncommon condition resulting from infection by achlorophyllous algae of the Prototheca species. Immunocompromised individuals are generally most susceptible to protothecal infection and tend to develop severe and disseminated disease. However, the association between protothecosis and HIV-induced immunosuppression is not clear, with only a handful of cases having been described to date. Here we report a case of cutaneous protothecosis in a Chinese man with previously undiagnosed HIV infection that responded well to oral itraconazole. © 2014 The Australasian College of Dermatologists.

  12. HEART TRANSPLANTATION IN PATIENTS WITH PREVIOUS OPEN HEART SURGERY

    Directory of Open Access Journals (Sweden)

    R. Sh. Saitgareev

    2016-01-01

    Full Text Available Heart Transplantation (HTx to date remains the most effective and radical method of treatment of patients with end-stage heart failure. The defi cit of donor hearts is forcing to resort increasingly to the use of different longterm mechanical circulatory support systems, including as a «bridge» to the follow-up HTx. According to the ISHLT Registry the number of recipients underwent cardiopulmonary bypass surgery increased from 40% in the period from 2004 to 2008 to 49.6% for the period from 2009 to 2015. HTx performed in repeated patients, on the one hand, involves considerable technical diffi culties and high risks; on the other hand, there is often no alternative medical intervention to HTx, and if not dictated by absolute contradictions the denial of the surgery is equivalent to 100% mortality. This review summarizes the results of a number of published studies aimed at understanding the immediate and late results of HTx in patients, previously underwent open heart surgery. The effect of resternotomy during HTx and that of the specifi c features associated with its implementation in recipients previously operated on open heart, and its effects on the immediate and long-term survival were considered in this review. Results of studies analyzing the risk factors for perioperative complications in repeated recipients were also demonstrated. Separately, HTx risks after implantation of prolonged mechanical circulatory support systems were examined. The literature does not allow to clearly defi ning the impact factor of earlier performed open heart surgery on the course of perioperative period and on the prognosis of survival in recipients who underwent HTx. On the other hand, subject to the regular fl ow of HTx and the perioperative period the risks in this clinical situation are justifi ed as a long-term prognosis of recipients previously conducted open heart surgery and are comparable to those of patients who underwent primary HTx. Studies

  13. Fulminant Pneumococcal Pericarditis in a Previously Healthy Patient.

    Science.gov (United States)

    Trpkov, Cvetan; Nath, Ermin; Moon, Michael; Windram, Jonathan; Graham, Michelle M

    2017-04-01

    Purulent pericarditis is a rare acutely life-threatening condition. Initial symptoms, signs, and investigations can be nonspecific. Echocardiography is invaluable for establishing the diagnosis and initial management. We present a case of a previously healthy patient with purulent pericarditis caused by Streptococcus pneumoniae in the absence of a primary focus of infection. The patient deteriorated rapidly with cardiac tamponade and septic shock and was managed successfully by a combined medical and surgical approach. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  14. In vivo strains in the femur of the Virginia opossum (Didelphis virginiana) during terrestrial locomotion: testing hypotheses of evolutionary shifts in mammalian bone loading and design.

    Science.gov (United States)

    Butcher, Michael T; White, Bartholomew J; Hudzik, Nathan B; Gosnell, W Casey; Parrish, John H A; Blob, Richard W

    2011-08-01

    Terrestrial locomotion can impose substantial loads on vertebrate limbs. Previous studies have shown that limb bones from cursorial species of eutherian mammals experience high bending loads with minimal torsion, whereas the limb bones of non-avian reptiles (and amphibians) exhibit considerable torsion in addition to bending. It has been hypothesized that these differences in loading regime are related to the difference in limb posture between upright mammals and sprawling reptiles, and that the loading patterns observed in non-avian reptiles may be ancestral for tetrapod vertebrates. To evaluate whether non-cursorial mammals show loading patterns more similar to those of sprawling lineages, we measured in vivo strains in the femur during terrestrial locomotion of the Virginia opossum (Didelphis virginiana), a marsupial that uses more crouched limb posture than most mammals from which bone strains have been recorded, and which belongs to a clade phylogenetically between reptiles and the eutherian mammals studied previously. The presence of substantial torsion in the femur of opossums, similar to non-avian reptiles, would suggest that this loading regime likely reflects an ancestral condition for tetrapod limb bone design. Strain recordings indicate the presence of both bending and appreciable torsion (shear strain: 419.1 ± 212.8 με) in the opossum femur, with planar strain analyses showing neutral axis orientations that placed the lateral aspect of the femur in tension at the time of peak strains. Such mediolateral bending was unexpected for a mammal running with near-parasagittal limb kinematics. Shear strains were similar in magnitude to peak compressive axial strains, with opossum femora experiencing similar bending loads but higher levels of torsion compared with most previously studied mammals. Analyses of peak femoral strains led to estimated safety factor ranges of 5.1-7.2 in bending and 5.5-7.3 in torsion, somewhat higher than typical mammalian values

  15. Do Job Demands of Chinese Manufacturing Employees Predict Positive or Negative Outcomes? A Test of Competing Hypotheses.

    Science.gov (United States)

    Cheung, Janelle H; Sinclair, Robert R; Shi, Junqi; Wang, Mo

    2015-12-01

    Karasek's job demands-control (JDC) model posits that job control can buffer against the harmful effects of demands experienced by employees. A large volume of JDC research has obtained support for the main effects of demands and control, but not the interactive effects. Recent research on the challenge-hindrance stressors framework, however, found that work stressors may not always be deleterious, suggesting alternative hypotheses about the effects of demands and control. The present study therefore examined competing hypotheses concerning the effects of job demands on occupational health outcomes. Using a sample of 316 employees in a Chinese manufacturing company, we found that, consistent with the challenge-hindrance framework, production demands were challenge stressors associated with favourable outcomes (i.e. job satisfaction and psychological well-being). In addition, results showed that the interactive role of job control depended on the nature of outcome variables. Future recommendations and implications of findings are discussed. Copyright © 2014 John Wiley & Sons, Ltd.

  16. Phylemon 2.0: a suite of web-tools for molecular evolution, phylogenetics, phylogenomics and hypotheses testing.

    Science.gov (United States)

    Sánchez, Rubén; Serra, François; Tárraga, Joaquín; Medina, Ignacio; Carbonell, José; Pulido, Luis; de María, Alejandro; Capella-Gutíerrez, Salvador; Huerta-Cepas, Jaime; Gabaldón, Toni; Dopazo, Joaquín; Dopazo, Hernán

    2011-07-01

    Phylemon 2.0 is a new release of the suite of web tools for molecular evolution, phylogenetics, phylogenomics and hypotheses testing. It has been designed as a response to the increasing demand of molecular sequence analyses for experts and non-expert users. Phylemon 2.0 has several unique features that differentiates it from other similar web resources: (i) it offers an integrated environment that enables evolutionary analyses, format conversion, file storage and edition of results; (ii) it suggests further analyses, thereby guiding the users through the web server; and (iii) it allows users to design and save phylogenetic pipelines to be used over multiple genes (phylogenomics). Altogether, Phylemon 2.0 integrates a suite of 30 tools covering sequence alignment reconstruction and trimming; tree reconstruction, visualization and manipulation; and evolutionary hypotheses testing.

  17. Phylemon 2.0: a suite of web-tools for molecular evolution, phylogenetics, phylogenomics and hypotheses testing

    Science.gov (United States)

    Sánchez, Rubén; Serra, François; Tárraga, Joaquín; Medina, Ignacio; Carbonell, José; Pulido, Luis; de María, Alejandro; Capella-Gutíerrez, Salvador; Huerta-Cepas, Jaime; Gabaldón, Toni; Dopazo, Joaquín; Dopazo, Hernán

    2011-01-01

    Phylemon 2.0 is a new release of the suite of web tools for molecular evolution, phylogenetics, phylogenomics and hypotheses testing. It has been designed as a response to the increasing demand of molecular sequence analyses for experts and non-expert users. Phylemon 2.0 has several unique features that differentiates it from other similar web resources: (i) it offers an integrated environment that enables evolutionary analyses, format conversion, file storage and edition of results; (ii) it suggests further analyses, thereby guiding the users through the web server; and (iii) it allows users to design and save phylogenetic pipelines to be used over multiple genes (phylogenomics). Altogether, Phylemon 2.0 integrates a suite of 30 tools covering sequence alignment reconstruction and trimming; tree reconstruction, visualization and manipulation; and evolutionary hypotheses testing. PMID:21646336

  18. Local convergence of a multi-step high order method with divided differences under hypotheses on the first derivative

    Directory of Open Access Journals (Sweden)

    Ioannis K. Argyros

    2017-12-01

    Full Text Available This paper is devoted to the study of a multi-step method with divided differences for solving nonlinear equations in Banach spaces. In earlier studies, hypotheses on the Fréchet derivative up to the sixth order of the operator under consideration is used to prove the convergence of the method. That restricts the applicability of the method. In this paper we extended the applicability of the sixth-order multi-step method by using only hypotheses on the first derivative of the operator involved. Our convergence conditions are weaker than the conditions used in earlier studies. Numerical examples where earlier results cannot be applied to solve equations but our results can be applied are also given in this study.

  19. Relationship of deer and moose populations to previous winters' snow

    Science.gov (United States)

    Mech, L.D.; McRoberts, R.E.; Peterson, R.O.; Page, R.E.

    1987-01-01

    (1) Linear regression was used to relate snow accumulation during single and consecutive winters with white-tailed deer (Odocoileus virginianus) fawn:doe ratios, mosse (Alces alces) twinning rates and calf:cow ratios, and annual changes in deer and moose populations. Significant relationships were found between snow accumulation during individual winters and these dependent variables during the following year. However, the strongest relationships were between the dependent variables and the sums of the snow accumulations over the previous three winters. The percentage of the variability explained was 36 to 51. (2) Significant relationships were also found between winter vulnerability of moose calves and the sum of the snow accumulations in the current, and up to seven previous, winters, with about 49% of the variability explained. (3) No relationship was found between wolf numbers and the above dependent variables. (4) These relationships imply that winter influences on maternal nutrition can accumulate for several years and that this cumulative effect strongly determines fecundity and/or calf and fawn survivability. Although wolf (Canis lupus L.) predation is the main direct mortality agent on fawns and calves, wolf density itself appears to be secondary to winter weather in influencing the deer and moose populations.

  20. Incidence of Acneform Lesions in Previously Chemically Damaged Persons-2004

    Directory of Open Access Journals (Sweden)

    N Dabiri

    2008-04-01

    Full Text Available ABSTRACT: Introduction & Objective: Chemical gas weapons especially nitrogen mustard which was used in Iraq-Iran war against Iranian troops have several harmful effects on skin. Some other chemical agents also can cause acne form lesions on skin. The purpose of this study was to compare the incidence of acneform in previously chemically damaged soldiers and non chemically damaged persons. Materials & Methods: In this descriptive and analytical study, 180 chemically damaged soldiers, who have been referred to dermatology clinic between 2000 – 2004, and forty non-chemically damaged people, were chosen randomly and examined for acneform lesions. SPSS software was used for statistic analysis of the data. Results: The mean age of the experimental group was 37.5 ± 5.2 and that of the control group was 38.7 ± 5.9 years. The mean percentage of chemical damage in cases was 31 percent and the time after the chemical damage was 15.2 ± 1.1 years. Ninety seven cases (53.9 percent of the subjects and 19 people (47.5 percent of the control group had some degree of acne. No significant correlation was found in incidence, degree of lesions, site of lesions and age of subjects between two groups. No significant correlation was noted between percentage of chemical damage and incidence and degree of lesions in case group. Conclusion: Incidence of acneform lesions among previously chemically injured peoples was not higher than the normal cases.