273 research outputs found

    Additional Thoughts on Rigor in Wildlife Science: Unappreciated Impediments

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    Traditionally, most scientists accepted reductionist and mechanistic approaches as the rigorous way to do science. Sells et al. (2018) recently raised the argument about reliability in wildlife science. Chamberlin (1890), Platt (1964), Romesburg (1981, 1991, 2009), and Williams (1997) were rightly referenced as very influential papers. My intention in this letter is not to refute the essence of the Sells et al. (2018) commentary but to add seldom addressed but important aspects that influence the attainment of rigor and certainty in wildlife studies. The elements of a rigorous approach (i.e., strong inference) as described by Platt (1964) included devising alternative hypotheses, devising ≄1 crucial experiments that will exclude ≄1 of the hypotheses, and carrying out the experiment to get a clean result. The process was then repeated using logical inductive trees (i.e., a continually bifurcated statement hypotheses approach) to obtain the essential cause for the effect. Platt (1964) agreed with Popper (1959) that science advanced only by disproof. He argued that this was a hard doctrine and leads to disputations between scientists, but that Chamberlin\u27s (1890) method of multiple working hypotheses helped to remove that difficulty. Platt (1964) emphasized inductive inference and crucial and critical experiments whereby alternate hypotheses are refuted. Romesburg (1981) explained that in wildlife biology, induction (reliable associations) and retroduction (developing hypotheses) were the basis for almost all wildlife research but were not sufficient. He proposed the hypothetical‐deductive (H‐D) method as a more reliable approach. Citing Harvey (1969), and Popper (1962), Romesburg (1981:294) explained that “Starting with the research hypothesis, usually obtained by retroduction, predictions are made about other classes of facts that should be true if the research hypothesis is actually true.” The hypothesis is then tested indirectly by using logic to deduce one or more test consequences (Romesburg 2014). Data are then collected in a statistical framework. Romesburg (1981) distinguished between a research hypothesis (i.e., a conjecture about some process) versus a statistical hypothesis (i.e., a conjecture about classes of facts encompassed by the process). Williams (1997) clearly explained the differences between necessary and sufficient causation and gave examples of the coherent logic both entailed. He summarized that the science endeavor included theory, hypotheses, predictions, observations, and comparison of predictions against data, and argued that inductive and deductive logic were required for testing hypotheses. Importantly, Williams (1997:1014) recognized that wildlife biology often involves simultaneous complementary explanatory factors, requiring “the framing of many scientifically interesting issues about cause and effect in terms of the relative contribution of multiple causal factors.” Over the years, many others have addressed the issue of rigor and reliability in the Journal of Wildlife Management (JWM) and the Wildlife Society Bulletin (WSB) either directly (McNab 1983, Eberhardt 1988, Anderson 2001) or indirectly (Steidl et al. 1997, Guthery et al. 2001). This is not a complete list and is limited primarily to JWM and WSB but gives an idea of the wide interest in achieving reliable results from wildlife studies

    Musicians’ perceptions and experiences of using simulation training to develop performance skills

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    Simulation has been applied as a tool for learning and training in sports, psychology and medicine for some time, but its current use and potential for training musicians is less well understood. The aim of this study was to explore musicians’ perceptions and experiences of using simulated performance environments. Nine conservatory students performed in two simulations, each with interactive virtual elements and vivid environmental cues: a recital with a virtual audience and an audition with virtual judges. Qualitative data were collected through a focus group interview and written reflective commentaries. Thematic analysis highlighted the musicians’ experiences in terms of (1) their anticipation of using the simulations, (2) the process of performing in the simulations, (3) the usefulness of simulation as a tool for developing performance skills and (4) ways of improving simulation training. The results show that while simulation was new to the musicians and individual levels of immersion differed, the musicians saw benefits in the approach for developing, experimenting with and enhancing their performance skills. Specifically, the musicians emphasised the importance of framing the simulation experience with plausible procedures leading to and following on from the performance, and they recognised the potential for combining simulation with complementary training techniques

    Correlations of behavioral deficits with brain pathology assessed through longitudinal MRI and histopathology in the R6/1 mouse model of huntington's disease

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    Huntington's disease (HD) is caused by the expansion of a CAG repeat in the huntingtin (HTT) gene. The R6 mouse models of HD express a mutant version of exon 1 HTT and typically develop motor and cognitive impairments, a widespread huntingtin (HTT) aggregate pathology and brain atrophy. Unlike the more commonly used R6/2 mouse line, R6/1 mice have fewer CAG repeats and, subsequently, a less rapid pathological decline. Compared to the R6/2 line, fewer descriptions of the progressive pathologies exhibited by R6/1 mice exist. The association between the molecular and cellular neuropathology with brain atrophy, and with the development of behavioral phenotypes remains poorly understood in many models of HD. In attempt to link these factors in the R6/1 mouse line, we have performed detailed assessments of behavior and of regional brain abnormalities determined through longitudinal, in vivo magnetic resonance imaging (MRI), as well as an end-stage, ex vivo MRI study and histological assessment. We found progressive decline in both motor and non-motor related behavioral tasks in R6/1 mice, first evident at 11 weeks of age. Regional brain volumes were generally unaffected at 9 weeks, but by 17 weeks there was significant grey matter atrophy. This age-related brain volume loss was validated using a more precise, semi-automated Tensor Based morphometry assessment. As well as these clear progressive phenotypes, mutant HTT (mHTT) protein, the hallmark of HD molecular pathology, was widely distributed throughout the R6/1 brain and was accompanied by neuronal loss. Despite these seemingly concomitant, robust pathological phenotypes, there appeared to be little correlation between the three main outcome measures: behavioral performance, MRI-detected brain atrophy and histopathology. In conclusion, R6/1 mice exhibit many features of HD, but the underlying mechanisms driving these clear behavioral disturbances and the brain volume loss, still remain unclear. © 2013 Rattray et al

    Neurobiological foundations of multisensory integration in people with autism spectrum disorders: the role of the medial prefrontal cortex.

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    This review aims to relate the sensory processing problems in people with autism spectrum disorders (ASD), especially multisensory integration (MSI), to the role of the medial prefrontal cortex (mPFC) by exploring neuroanatomical findings; brain connectivity and Default Network (DN); global or locally directed attention; and temporal multisensory binding. The mPFC is part of the brainÂżs DN, which is deactivated when attention is focused on a particular task and activated on rest when spontaneous cognition emerges. In those with ASD, it is hypoactive and the higher the social impairment the greater the atypical activity. With an immature DN, cross-modal integration is impaired, resulting in a collection of disconnected fragments instead of a coherent global perception. The deficit in MSI may lie in the temporal synchronization of neural networks. The time interval in which the stimulation of one sensory channel could influence another would be higher, preventing integration in the typical shorter time range. Thus, the underconnectivity between distant brain areas would be involved in top-down information processes (relying on global integration of data from different sources) and would enhance low level perception processes such as over focused attention to s

    Markers of serotonergic function in the orbitofrontal cortex and dorsal raphé nucleus predict individual variation in spatial-discrimination serial reversal learning.

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    Dysfunction of the orbitofrontal cortex (OFC) impairs the ability of individuals to flexibly adapt behavior to changing stimulus-reward (S-R) contingencies. Impaired flexibility also results from interventions that alter serotonin (5-HT) and dopamine (DA) transmission in the OFC and dorsomedial striatum (DMS). However, it is unclear whether similar mechanisms underpin naturally occurring variations in behavioral flexibility. In the present study, we used a spatial-discrimination serial reversal procedure to investigate interindividual variability in behavioral flexibility in rats. We show that flexibility on this task is improved following systemic administration of the 5-HT reuptake inhibitor citalopram and by low doses of the DA reuptake inhibitor GBR12909. Rats in the upper quintile of the distribution of perseverative responses during repeated S-R reversals showed significantly reduced levels of the 5-HT metabolite, 5-hydroxy-indoleacetic acid, in the OFC. Additionally, 5-HT2A receptor binding in the OFC of mid- and high-quintile rats was significantly reduced compared with rats in the low-quintile group. These perturbations were accompanied by an increase in the expression of monoamine oxidase-A (MAO-A) and MAO-B in the lateral OFC and by a decrease in the expression of MAO-A, MAO-B, and tryptophan hydroxylase in the dorsal raphé nucleus of highly perseverative rats. We found no evidence of significant differences in markers of DA and 5-HT function in the DMS or MAO expression in the ventral tegmental area of low- vs high-perseverative rats. These findings indicate that diminished serotonergic tone in the OFC may be an endophenotype that predisposes to behavioral inflexibility and other forms of compulsive behavior.This work was supported by Medical Research Council Grants (G0701500; G0802729), a 503 Wellcome Trust Programme Grant (grant number 089589/Z/09/Z), and by a Core Award 504 from the Medical Research Council and the Wellcome Trust to the Behavioural and Clinical 505 21 Neuroscience Institute (MRC Ref G1000183; WT Ref 093875/Z/10/Z). RLB was supported 506 by a studentship from the Medical Research Council. JA was supported by a Fellowship from 507 the Swedish Research Council (350-2012-230). BJ was supported by Fellowships from the 508 AXA Research Fund and the National Health and Medical Research Council of Australia. 509 Financial support from the Fredrik and Ingrid Thuring Foundation is also acknowledged.This is the accepted manuscript. The final version is available from Nature Publishing at http://www.nature.com/npp/journal/vaop/ncurrent/full/npp2014335a.html

    Organic Farming Improves Pollination Success in Strawberries

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    Pollination of insect pollinated crops has been found to be correlated to pollinator abundance and diversity. Since organic farming has the potential to mitigate negative effects of agricultural intensification on biodiversity, it may also benefit crop pollination, but direct evidence of this is scant. We evaluated the effect of organic farming on pollination of strawberry plants focusing on (1) if pollination success was higher on organic farms compared to conventional farms, and (2) if there was a time lag from conversion to organic farming until an effect was manifested. We found that pollination success and the proportion of fully pollinated berries were higher on organic compared to conventional farms and this difference was already evident 2–4 years after conversion to organic farming. Our results suggest that conversion to organic farming may rapidly increase pollination success and hence benefit the ecosystem service of crop pollination regarding both yield quantity and quality

    Validation of the Comprehensive Feeding Practices Questionnaire with parents of 10-to-12-year-olds

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    Abstract Background: There is a lack of validated instruments for quantifying feeding behavior among parents of older children and adolescents. The Comprehensive Feeding Practices Questionnaire (CFPQ) is a self-report measure to assess multiple parental feeding practices. The CFPQ is originally designed for use with parents of children ranging in age from about 2 to 8 years. It is previously validated with American and French parents of children within this age range. The aim of the present study was to adapt and test the validity of this measure with parents of older children (10-to-12-year-olds) in a Norwegian setting. Methods: A sample of 963 parents of 10-to-12-year-olds completed a Norwegian, slightly adapted version of the CFPQ. Scale analyses were performed to test the validity of the instrument in our sample. Results: Although a few problematic items and scales were revealed, scale analyses showed that the psychometric properties of the slightly adapted, Norwegian version of the CFPQ were surprisingly similar to those of the original CFPQ. Conclusions: Our results indicated that the CFPQ, with some small modifications, is a valid tool for measuring multiple parental feeding practices with parents of 10-to12-year-olds

    Heat and moisture exchangers (HMEs) and heated humidifiers (HHs) in adult critically ill patients: a systematic review, meta-analysis and meta-regression of randomized controlled trials

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    The aims of this systematic review and meta-analysis of randomized controlled trials are to evaluate the effects of active heated humidifiers (HHs) and moisture exchangers (HMEs) in preventing artificial airway occlusion and pneumonia, and on mortality in adult critically ill patients. In addition, we planned to perform a meta-regression analysis to evaluate the relationship between the incidence of artificial airway occlusion, pneumonia and mortality and clinical features of adult critically ill patients

    Extreme Conservation Leads to Recovery of the Virunga Mountain Gorillas

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    As wildlife populations are declining, conservationists are under increasing pressure to measure the effectiveness of different management strategies. Conventional conservation measures such as law enforcement and community development projects are typically designed to minimize negative human influences upon a species and its ecosystem. In contrast, we define “extreme” conservation as efforts targeted to deliberately increase positive human influences, including veterinary care and close monitoring of individual animals. Here we compare the impact of both conservation approaches upon the population growth rate of the critically endangered Virunga mountain gorillas (Gorilla beringei beringei), which increased by 50% since their nadir in 1981, from approximately 250 to nearly 400 gorillas. Using demographic data from 1967–2008, we show an annual decline of 0.7%±0.059% for unhabituated gorillas that received intensive levels of conventional conservation approaches, versus an increase 4.1%±0.088% for habituated gorillas that also received extreme conservation measures. Each group of habituated gorillas is now continuously guarded by a separate team of field staff during daylight hours and receives veterinary treatment for snares, respiratory disease, and other life-threatening conditions. These results suggest that conventional conservation efforts prevented a severe decline of the overall population, but additional extreme measures were needed to achieve positive growth. Demographic stochasticity and socioecological factors had minimal impact on variability in the growth rates. Veterinary interventions could account for up to 40% of the difference in growth rates between habituated versus unhabituated gorillas, with the remaining difference likely arising from greater protection against poachers. Thus, by increasing protection and facilitating veterinary treatment, the daily monitoring of each habituated group contributed to most of the difference in growth rates. Our results argue for wider consideration of extreme measures and offer a startling view of the enormous resources that may be needed to conserve some endangered species
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