bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differential organization of taxonomic and functional diversity in an urban woody plant metacommunity
Authors: Swan Christopher M. , Johnson Anna , Nowak David J. 
Published: October 2016

AbstractQuestionsUrban ecosystems present an opportunity to study ecological communities in the context of unprecedented environmental change. In the face of urban land conversion, ecologists observe new patterns of species composition, dominance, behaviour and dispersal. We propose a hypothetical socioeconomic template that describes a gradient in human investment in community composition to aid in organizing the human role in shaping urban biodiversity. We asked: (1) what is the relative magnitude of taxonomic and functional turnover of urban woody plant communities across different land‐use types; and (2) do land uses exhibiting higher intensity of human management of biodiversity support higher turnover over those with less human influence?LocationBaltimore, MD, USA (39°17′ N, 76°38′ W).MethodsWe examined patterns in woody plant biodiversity across 209 plots of different urban land uses. Six land‐use types were arranged along a gradient in the intensity through which humans are hypothesized to manage species composition at the plot scale. We calculated local, or α‐diversity, and compositional turnover, or β‐diversity, of taxonomic and functional diversity across plots within each land‐use type. We compared the magnitude of these biodiversity measures between land uses to test our conceptual template for how the intensity of human management can predict urban woody plant biodiversity.ResultsWe observed high taxonomic turnover in residential and commercial plots compared with vacant or open space land‐use areas. This was associated with a weaker, but similar, pattern in functional diversity. This was associated with low total abundance in residential and commercial plots. Furthermore, the number of unique species was extremely high in the same land‐use types.ConclusionsOur observations help explain why turnover can be high in heavily managed plots relative to vacant land. In patches without heavy human management, we found low levels of turnover. This highlights the importance of assessing diversity both locally and at the level of turnover between patches. Management and policy can benefit from the perspective embodied in the conceptual approach tested here.
A Joint Modeling Approach for Multivariate Survival Data with Random Length
Authors: Liu Shuling , Manatunga Amita K. , Peng Limin , Marcus Michele 
Published: October 2016

SummaryIn many biomedical studies that involve correlated data, an outcome is often repeatedly measured for each individual subject along with the number of these measurements, which is also treated as an observed outcome. This type of data has been referred as multivariate random length data by Barnhart and Sampson (1995). A common approach to handling such type of data is to jointly model the multiple measurements and the random length. In previous literature, a key assumption is the multivariate normality for the multiple measurements. Motivated by a reproductive study, we propose a new copula-based joint model which relaxes the normality assumption. Specifically, we adopt the Clayton–Oakes model for multiple measurements with flexible marginal distributions specified as semi-parametric transformation models. The random length is modeled via a generalized linear model. We develop an approximate EM algorithm to derive parameter estimators and standard errors of the estimators are obtained through bootstrapping procedures and the finite-sample performance of the proposed method is investigated using simulation studies. We apply our method to the Mount Sinai Study of Women Office Workers (MSSWOW), where women were prospectively followed for 1 year for studying fertility.
An Adaptive Mantel–Haenszel Test for Sensitivity Analysis in Observational Studies
Authors: Rosenbaum Paul R. , Small Dylan S. 
Published: October 2016

SummaryIn a sensitivity analysis in an observational study with a binary outcome, is it better to use all of the data or to focus on subgroups that are expected to experience the largest treatment effects? The answer depends on features of the data that may be difficult to anticipate, a trade-off between unknown effect-sizes and known sample sizes. We propose a sensitivity analysis for an adaptive test similar to the Mantel–Haenszel test. The adaptive test performs two highly correlated analyses, one focused analysis using a subgroup, one combined analysis using all of the data, correcting for multiple testing using the joint distribution of the two test statistics. Because the two component tests are highly correlated, this correction for multiple testing is small compared with, for instance, the Bonferroni inequality. The test has the maximum design sensitivity of two component tests. A simulation evaluates the power of a sensitivity analysis using the adaptive test. Two examples are presented. An R package, sensitivity2x2xk, implements the procedure.
Greedy Outcome Weighted Tree Learning of Optimal Personalized Treatment Rules
Authors: Zhu Ruoqing , Zhao Ying-Qi , Chen Guanhua , Ma Shuangge , Zhao Hongyu 
Published: October 2016

Summary
We propose a subgroup identification approach for inferring optimal and interpretable personalized treatment rules with high-dimensional covariates. Our approach is based on a two-step greedy tree algorithm to pursue signals in a high-dimensional space. In the first step, we transform the treatment selection problem into a weighted classification problem that can utilize tree-based methods. In the second step, we adopt a newly proposed tree-based method, known as reinforcement learning trees, to detect features involved in the optimal treatment rules and to construct binary splitting rules. The method is further extended to right censored survival data by using the accelerated failure time model and introducing double weighting to the classification trees. The performance of the proposed method is demonstrated via simulation studies, as well as analyses of the Cancer Cell Line Encyclopedia (CCLE) data and the Tamoxifen breast cancer data.
Survival Model Construction Guided by Fit and Predictive Strength
Authors: Chauvel Cécile , O'Quigley John 
Published: October 2016

SummarySurvival model construction can be guided by goodness-of-fit techniques as well as measures of predictive strength. Here, we aim to bring together these distinct techniques within the context of a single framework. The goal is how to best characterize and code the effects of the variables, in particular time dependencies, when taken either singly or in combination with other related covariates. Simple graphical techniques can provide an immediate visual indication as to the goodness-of-fit but, in cases of departure from model assumptions, will point in the direction of a more involved and richer alternative model. These techniques appear to be intuitive. This intuition is backed up by formal theorems that underlie the process of building richer models from simpler ones. Measures of predictive strength are used in conjunction with these goodness-of-fit techniques and, again, formal theorems show that these measures can be used to help identify models closest to the unknown non-proportional hazards mechanism that we can suppose generates the observations. Illustrations from studies in breast cancer show how these tools can be of help in guiding the practical problem of efficient model construction for survival data.
Synaptic pathology in the cerebellar dentate nucleus in chronic multiple sclerosis
Authors: Albert Monika , Barrantes‐Freer Alonso , Lohrberg Melanie , Antel Jack P. , Prineas John W. , Palkovits Miklós , Wolff Joachim R. , Brück Wolfgang , Stadelmann Christine 
Published: October 2016

AbstractIn multiple sclerosis, cerebellar symptoms are associated with clinical impairment and an increased likelihood of progressive course. Cortical atrophy and synaptic dysfunction play a prominent role in cerebellar pathology and although the dentate nucleus is a predilection site for lesion development, structural synaptic changes in this region remain largely unexplored. Moreover, the mechanisms leading to synaptic dysfunction have not yet been investigated at an ultrastructural level in multiple sclerosis. Here, we report on synaptic changes of dentate nuclei in post‐mortem cerebella of 16 multiple sclerosis patients and eight controls at the histological level as well as an electron microscopy evaluation of afferent synapses of the cerebellar dentate and pontine nuclei of one multiple sclerosis patient and one control. We found a significant reduction of afferent dentate synapses in multiple sclerosis, irrespective of the presence of demyelination, and a close relationship between glial processes and dentate synapses. Ultrastructurally, we show autophagosomes containing degradation products of synaptic vesicles within dendrites, residual bodies within intact‐appearing axons and free postsynaptic densities opposed to astrocytic appendages. Our study demonstrates loss of dentate afferent synapses and provides, for the first time, ultrastructural evidence pointing towards neuron‐autonomous and neuroglia‐mediated mechanisms of synaptic degradation in chronic multiple sclerosis.
A vocational rehabilitation intervention for young adults with physical disabilities: participants' perception of beneficial attributes
Authors: Bal M. I. , Sattoe J. N. T. , van Schaardenburgh N. R. , Floothuis M. C. S. G. , Roebroeck M. E. , Miedema H. S. 
Published: October 2016

AbstractBackgroundFinding and maintaining employment is a major challenge for young adults with physical disabilities and their work participation rate is lower than that of healthy peers. This paper is about a program that supports work participation amongst young adults with chronic physical disabilities. The study aims to explore their experienced barriers and facilitators for finding and maintaining employment after starting this program, the participant‐perceived beneficial attributes of the program and participants' recommendations for additional intervention components.MethodsSemi‐structured interviews (n = 19) were held with former intervention participations. Interviews were recorded and transcribed ad verbatim. Themes were derived using the phenomenological approach.ResultsPhysical functions and capacities, supervisor's attitude, self‐esteem and self‐efficacy and openness and assertiveness were experienced barriers and facilitators for finding and maintaining employment. Improvement of self‐promoting skills and disclosure skills through job interview‐training, increased self‐esteem or self‐efficacy through peer‐support, a suitable job through job placement, improvement of work ability through arrangement of adjusted work conditions and change of supervisor's attitude through education provided to the supervisor were perceived as beneficial attributes of the intervention. Respondents recommended to incorporate assertiveness and openness skills training into future intervention programs.ConclusionsThe findings suggest that programs supporting work participation should be designed to provide challenging, real‐world experiential opportunities that provide young adults with physical disabilities with new insights, self‐efficacy and life skills. Also, such programs should facilitate context centered learning. Former intervention participants, therefore, evaluated job‐interview training, sharing learning and social experiences with peers, job placement, arrangement of adjusted work conditions and education as beneficial attributes of the ‘At Work’ program. In addition, they recommended, to incorporate more training on assertiveness and disclosure. We advise professionals to include these beneficial attributes in similar interventions in other contexts.
Use of the ages and stages questionnaire adapted for South Africa and Zambia
Authors: Hsiao C. , Richter L. , Makusha T. , Matafwali B. , van Heerden A. , Mabaso M. 
Published: October 2016

AbstractBackgroundThere are few readily available, relatively easy to use and culturally adaptable developmental assessment tools for young children in southern Africa.The overarching aim of this study is to test the psychometric properties, contextual appropriateness and cut‐off scores across 21 age groups of the Ages and Stages Questionnaire Third Edition (Squires & Bricker, ) among a group of typically developing children in South Africa and Zambia through a combination of both caregiver‐report and direct observations, and to compare children's performance across sociodemographic variables.MethodsThe sample consisted of 853 children (50.5% Zambia, with 50.1% girls for Zambia and 50% girls for South Africa) aged 2 months to 60 months. Information on caregiver employment, education and household assets were also obtained.ResultsThe psychometric properties of the ASQ‐3 in southern Africa are consistent with those found in the extant literature. Analysis of item difficulty at each age reveals adequate levels of difficulty for majority of the items, with exception of the problem solving domain where half of the items at 54 and 60 months have poor pass rates. Sociodemographic variables were significantly associated with children's performance: higher caregiver levels of education are associated with higher toddler scores on the personal–social domain and higher preschooler scores on the problem solving domain; children whose caregivers earn a salary have higher fine motor scores during toddlerhood and higher problem solving scores during preschool and children who attend preschools have higher gross motor scores during toddlerhood and higher fine motor scores during the preschool years.ConclusionsFindings provide evidence to support the psychometric properties and feasibility of using the ASQ‐3 in both South Africa and Zambia through a combination of caregiver‐report and direct observations.
Evaluating the Incredible Years Toddler Parenting Programme with parents of toddlers in disadvantaged (Flying Start) areas of Wales
Authors: Hutchings J. , Griffith N. , Bywater T. , Williams M. E. 
Published: October 2016

SummaryBackgroundEarly risk factors for poor child outcomes are well established, and some group parenting programmes have demonstrated good outcomes for children under 3 years of age. This randomized controlled trial evaluated the effectiveness of the Incredible Years® Toddler Parenting Programme with parents of 1‐year‐old and 2‐year‐old children recruited by staff in disadvantaged Flying Start areas across Wales.MethodsEighty‐nine families with a child aged between 12 and 36 months at baseline participated in a pragmatic community‐based trial of the programme in eight Flying Start areas. Outcomes were measured at baseline, 6 months and 12 months using measures of parental mental health, competence, child behaviour, child development, home environment and blinded‐observation of parent–child interactions.ResultsSignificant intervention group improvements were found in parental mental well‐being and observed praise at 6 months. Significant improvements for the intervention group at 12 months included child development, home environment and parental depression.ConclusionThe study provides preliminary evidence for programme attendance.
Responses to Interpersonal Stress: Normative Changes Across Childhood and the Impact of Peer Victimization
Authors: Troop‐Gordon Wendy , Sugimura Niwako , Rudolph Karen D. 
Published: October 2016

This research examined the development of stress responses across second to sixth grades and whether exposure to peer victimization alters stress response trajectories. Youth (338 girls; 298 boys; Mage = 7.97 years, SD = .37) reported on stress responses; teachers and youth reported on peer victimization. Latent growth curve modeling revealed an increase in effortful engagement responses and a decrease in disengagement and involuntary engagement responses during this period. Peer victimization disrupted these normative trajectories, resulting in less effortful engagement and more effortful disengagement and involuntary stress responses in early adolescence. These findings suggest that early peer victimization sensitizes youth to stress by interfering with the development of effective coping and fostering maladaptive stress responses.
The Impact of Brand and Attention on Consumers’ Willingness to Pay: Evidence from an Eye Tracking Experiment
Authors: Lewis Karen E. , Grebitus Carola , Nayga Rodolfo M. 
Published: October 2016

In the field of agricultural economics, willingness to pay (WTP) studies often do not include information regarding the brand of the product. Therefore, we conducted an auction examining consumer WTP for branded and unbranded energy drinks containing different sweeteners. Eye tracking was used to capture the magnitude of attention spent by participants on specific areas of interest regarding the energy drinks in the auction (e.g., brand). Results indicate that attention to brand, package attributes, and product information had a varying impact on WTP depending on the brand examined. Results show that the presence of brand had an impact on WTP for certain brands. Also, as more attention was paid to particular stimuli regarding the energy drinks, individuals were more likely to either increase or decrease their WTP. These results have implications for both marketers of branded food products as well as researchers eliciting consumers’ preferences and WTP values for products that can be branded in the marketplace.Les impacts des marques de commerce et de l'attention du consommateur sur la volonté de payer: les résultats d'une expérience de suivi oculaire. Au sein de l'économie agricole, les études concernant la volonté de payer ne comprennent souvent pas les informations concernant les marques de commerce des produits. Nous avons donc mené une vente aux enchères pour examiner la volonté de payer des consommateurs pour des boissons énergisantes de marque et sans marque. Le suivi oculaire a été utilisé afin de mesurer l'intensité de l'attention des participants sur certains centres d'intérêt concernant les boissons énergisantes disponibles aux enchères (comme la marque). Les résultats démontrent que : l'attention portée à la marque de commerce, aux attributs de l'emballage et aux informations concernant le produit a un impact sur la volonté de payer pour certaines marques. De plus, une augmentation de l'attention pour un stimulus en particulier des boissons énergisantes rendait l'individu plus apte à augmenter ou diminuer sa volonté de payer. Ces résultats ont des répercussions autant pour les spécialistes du marketing des produits alimentaires de marque que pour les chercheurs voulant recueillir les préférences et la volonté de payer des consommateurs pour la commercialisation de produits destinés au marché.
The Effects of NAFTA/CUSFTA on Agricultural Trade Flows: An Empirical Investigation
Authors: Ghazalian Pascal L. 
Published: October 2016

This paper examines the effects of the North American Free Trade Agreement (NAFTA) and its predecessor, the Canada‐United States Free Trade Agreement (CUSFTA), on agricultural trade flows at disaggregated product categories. The empirical analysis is implemented through gravity models using different econometric methods. It accounts for the baseline NAFTA/CUSFTA‐unrelated magnitudes of trade between member countries throughout the assessment of the NAFTA/CUSFTA trade effects. The benchmark estimates show considerable differences across agricultural product categories. The net post‐NAFTA/CUSFTA magnitudes of trade between member countries are found to be markedly low in some cases, underlining missed regional trade opportunities. The empirical analysis proceeds to estimate the NAFTA/CUSFTA trade effects by time period and by bilateral trading partnership, revealing important variations.Cet article examine les effets de l'Accord de Libre‐Échange Nord‐Américain (ALÉNA) et de son prédécesseur, l'Accord de Libre‐Échange entre le Canada et les États‐Unis (ALÉCÉU), sur les flux commerciaux agricoles au niveau des catégories ventilées. L'analyse empirique est mise en œuvre grâce à des modèles de gravité en utilisant une variété de méthodes économétriques. Elle compte pour la ligne de base des magnitudes non‐reliées à l'ALÉNA/ALÉCÉU du commerce entre les pays membres à travers l′évaluation des effets de l'ALÉNA/ALÉCÉU sur le commerce. Les estimations de référence montrent des différences considérables entre les catégories de produits agricoles. Les magnitudes post‐ALÉNA/ALÉCÉU nettes du commerce entre les pays membres se trouvent d′être considérablement faibles dans certains cas. Ces résultats soulignent des opportunités commerciales régionales manquées. L'analyse empirique procède à estimer les effets de l'ALÉNA/ALÉCÉU sur le commerce par période et par partenariat commercial bilatéral, et elle montre des variations importantes.
Quality of life following fistulotomy – short term follow‐up
Authors: Owen H. A. , Buchanan G. N. , Schizas A. , Emmanuel A. , Cohen R. , Williams A. B. 
Published: October 2016

AbstractAimAnal fistula causes pain and discharge of pus and blood. Treatment by fistulotomy has the highest success, but can risk continence; treatment needs to balance cure with continence. This study assessed the impact of fistulotomy on quality of life (QOL) and continence.MethodPatients selected for fistulotomy prospectively completed the St Mark's Continence Score (full incontinence = 24) and Short Form‐36 questionnaires preoperatively at two institutions with an interest in anal fistula. Patients were reassessed 3 months’ postoperatively.ResultsThere were 52 patients with a median age of 44 (range 19–82) years; 10 were women. Preoperative continence scores were median 0 (range 0–23) and there was no significant difference compared with postoperative scores (median 1, range 0–24). Following fistulotomy QOL was significantly improved in four of eight domains – Bodily Pain (P < 0.001), Vitality (P < 0.01), Social Functioning (P < 0.05) and Mental Health (P < 0.001) – and returned to that of the general population. QOL for patients with intersphincteric fistula improved postfistulotomy, and for those with trans‐sphincteric fistula it remained the same. Data were further examined in two groups, with and without deterioration in continence score. Where continence improved postoperatively, QOL improved in three domains; where continence deteriorated QOL improved in two domains (P < 0.05). Patients with postoperative continence scores of < 5 had worse QOL than those scoring 4 or less.ConclusionQOL significantly improved at 3 months’ follow‐up after fistulotomy where continence was maintained or a small reduction occurred.