bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bayesian methods for setting sample sizes and choosing allocation ratios in phase II clinical trials with time‐to‐event endpoints
Authors: Cotterill Amy , Whitehead John 
Published: January 2015

Conventional phase II trials using binary endpoints as early indicators of a time‐to‐event outcome are not always feasible. Uveal melanoma has no reliable intermediate marker of efficacy. In pancreatic cancer and viral clearance, the time to the event of interest is short, making an early indicator unnecessary. In the latter application, Weibull models have been used to analyse corresponding time‐to‐event data.Bayesian sample size calculations are presented for single‐arm and randomised phase II trials assuming proportional hazards models for time‐to‐event endpoints. Special consideration is given to the case where survival times follow the Weibull distribution. The proposed methods are demonstrated through an illustrative trial based on uveal melanoma patient data. A procedure for prior specification based on knowledge or predictions of survival patterns is described. This enables investigation into the choice of allocation ratio in the randomised setting to assess whether a control arm is indeed required.The Bayesian framework enables sample sizes consistent with those used in practice to be obtained. When a confirmatory phase III trial will follow if suitable evidence of efficacy is identified, Bayesian approaches are less controversial than for definitive trials. In the randomised setting, a compromise for obtaining feasible sample sizes is a loss in certainty in the specified hypotheses: the Bayesian counterpart of power. However, this approach may still be preferable to running a single‐arm trial where no data is collected on the control treatment. This dilemma is present in most phase II trials, where resources are not sufficient to conduct a definitive trial. Copyright © 2015 John Wiley & Sons, Ltd.
Analogy, higher order thinking, and education
Authors: Richland Lindsey Engle , Simms Nina 
Published: January 2015

Analogical reasoning, the ability to understand phenomena as systems of structured relationships that can be aligned, compared, and mapped together, plays a fundamental role in the technology rich, increasingly globalized educational climate of the 21st century. Flexible, conceptual thinking is prioritized in this view of education, and schools are emphasizing ‘higher order thinking’, rather than memorization of a cannon of key topics. The lack of a cognitively grounded definition for higher order thinking, however, has led to a field of research and practice with little coherence across domains or connection to the large body of cognitive science research on thinking. We review literature on analogy and disciplinary higher order thinking to propose that relational reasoning can be productively considered the cognitive underpinning of higher order thinking. We highlight the utility of this framework for developing insights into practice through a review of mathematics, science, and history educational contexts. In these disciplines, analogy is essential to developing expert‐like disciplinary knowledge in which concepts are understood to be systems of relationships that can be connected and flexibly manipulated. At the same time, analogies in education require explicit support to ensure that learners notice the relevance of relational thinking, have adequate processing resources available to mentally hold and manipulate relations, and are able to recognize both the similarities and differences when drawing analogies between systems of relationships.WIREs Cogn Sci2015, 6:177–192. doi: 10.1002/wcs.1336This article is categorized under:Psychology > Reasoning and Decision MakingPsychology > Learning
Ionothermal Synthesis, Structure, and Bonding of theCatena‐Heteropolycation1∞[Sb2Se2]+
Authors: Groh Matthias F. , Breternitz Joachim , Ahmed Ejaz , Isaeva Anna , Efimova Anastasia , Schmidt Peer , Ruck Michael 
Published: January 2015

AbstractThe reaction of antimony and selenium in the Lewis‐acidic ionic liquid 1‐butyl‐3‐methyl‐imidazolium tetrachloridoaluminate, [BMIm]Cl·4.7AlCl3, yielded dark‐red crystals of [Sb2Se2]AlCl4. The formation starts above 160 °C; at about 190 °C, irreversible decomposition takes place. The compound crystallizes in the triclinic space groupP$\bar{1}$witha= 919.39(2) pm,b= 1137.92(3) pm,c= 1152.30(3) pm,α= 68.047(1)°,β= 78.115(1)°,γ= 72.530(1)°, andZ= 4. The structure is similar to that of [Sb2Te2]AlCl4but has only half the number of crystallographically independent atoms. Polycationic chains1∞[Sb2Se2]+form a pseudo‐hexagonal arrangement along [011$\bar{}$], which is interlaced by tetrahedral AlCl4–groups. Thecatena‐heteropolycation1∞[Sb2Se2]+is a sequence of three different four‐membered [Sb2Se2] rings. The chemical bonding scheme, established from the topological analysis of the real‐space bonding indicator ELI‐D, includes significantly polar covalent bonding in four‐member rings within the polycation. The rings are connected into an infinite chain by homonuclear non‐polar Sb–Sb bonds and highly polar Sb–Se bonds. Half of the selenium atoms are three‐bonded.
Laparoscopic Approach for Right‐Sided Intrahepatic Duct Stones: A Comparative Study of Laparoscopic Versus Open Treatment
Authors: Kim Young Ki , Han Ho‐Seong , Yoon Yoo‐Seok , Cho Jai Young , Lee Woohyung 
Published: January 2015

AbstractBackgroundDespite several attempts to treat intrahepatic duct (IHD) stones by laparoscopy, most cases have been limited to left‐sided IHD stones. The aim of this study was to evaluate the therapeutic feasibility and effectiveness of a laparoscopic approach for right‐sided IHD stones compared with the open approach for this disease.MethodsThis study included 34 consecutive patients who underwent laparoscopic (n = 17) and open (n = 17) treatment for right‐sided IHD stones from March 2005 to December 2011. Clinical data including the operative time, intraoperative blood loss, postoperative hospital length of stay, postoperative complications, stone clearance, and recurrence rate were retrospectively analyzed and compared between the two groups.ResultsOf the 17 patients who underwent laparoscopic treatment, three were treated using laparoscopic intrahepatic duct exploration alone and 14 patients were treated using laparoscopic liver resection. The operative time in the laparoscopic group was longer than that in the open group (432 ± 158 vs. 335 ± 85 min, p = 0.03). The laparoscopic group showed a lower postoperative complication rate than the open group (29 vs. 64 %, p = 0.039). There were no significant differences in intraoperative blood loss (988 ± 929 vs. 879 ± 942 ml, p = 0.737) or postoperative length of hospital stay (16 ± 22 vs. 12 ± 14 days, p = 0.221).ConclusionsThis study demonstrated that laparoscopic treatment could be an effective and safe therapeutic modality in selected patients with right‐sided IHD stones.
Direct and Indirect Effects of Caregiver Social Support on Adolescent Psychological Outcomes in Two South African AIDS‐Affected Communities
Authors: Casale Marisa , Cluver Lucie , Crankshaw Tamaryn , Kuo Caroline , Lachman Jamie M. , Wild Lauren G. 
Published: January 2015

AbstractCaregiver social support has been shown to be protective for caregiver mental health, parenting and child psychosocial outcomes. This is the first known analysis to quantitatively investigate the relationship between caregiver social support and adolescent psychosocial outcomes in HIV‐endemic, resource–scarce Southern African communities. A cross‐sectional household survey was conducted over 2009–2010 with 2,477 South African adolescents aged 10–17 and their adult caregivers (18 years or older) in one urban and one rural community in South Africa’s KwaZulu‐Natal province. Adolescent adjustment was assessed using adult caregiver reports of the Strengths and Difficulties questionnaire (SDQ), which measures peer problems, hyperactivity, conduct problems, emotional symptoms and child prosocial behavior. Hierarchical linear regressions and multiple mediation analyses, using bootstrapping procedures, were conducted to assess for: (a) direct effects of more caregiver social support on better adolescent psychosocial wellbeing; and (b) indirect effects mediated by better parenting and caregiver mental health. Direct associations (p < .001), and indirect associations mediated through better parenting, were found for all adolescent outcomes. Findings reinforce the importance of social support components within parenting interventions but also point to scope for positive intervention on adolescent psychosocial wellbeing through the broader family social network.
OpenMx 2.0: Extended Structural Equation and Statistical Modeling
Authors: Neale Michael C. , Hunter Michael D. , Pritikin Joshua N. , Zahery Mahsa , Brick Timothy R. , Kirkpatrick Robert M. , Estabrook Ryne , Bates Timothy C. , Maes Hermine H. , Boker Steven M. 
Published: January 2015

AbstractThe new software package OpenMx 2.0 for structural equation and other statistical modeling is introduced and its features are described. OpenMx is evolving in a modular direction and now allows a mix-and-match computational approach that separates model expectations from fit functions and optimizers. Major backend architectural improvements include a move to swappable open-source optimizers such as the newly written CSOLNP. Entire new methodologies such as item factor analysis and state space modeling have been implemented. New model expectation functions including support for the expression of models in LISREL syntax and a simplified multigroup expectation function are available. Ease-of-use improvements include helper functions to standardize model parameters and compute their Jacobian-based standard errors, access to model components through standard R $ mechanisms, and improved tab completion from within the R Graphical User Interface.
Considerations for Prophylactic Surgery in Asymptomatic Severe Cervical Stenosis
Authors: Sheikh Taha Abdel Majid , Shue Jennifer , Lebl Darren , Girardi Federico 
Published: January 2015

Background Cervical spondylotic myelopathy (CSM) is a devastating pathology that can severely impair quality of life. The symptoms in CSM progress slowly and often do not manifest until they become severe and potentially irreversible. There is a consensus that surgical intervention is warranted in symptomatic patients. The recovery of the neurologic deficit after surgical decompression of the spinal cord varies, and halting the progression of the disease remains the principle aim of surgery. Questions/Purposes The aim of this review is to address the key question of whether or not to intervene in cases that have radiographic evidence of significant cervical stenosis yet are asymptomatic or exhibit minimal symptoms? Methods The PubMed databases for publications that addressed asymptomatic cervical spondylotic myelopathy were reviewed. The relevant articles were selected after screening all the resulting abstracts. The references of the relevant articles were then reviewed, and cross references with titles discussing CSM were picked up for review. Results The search identified 14 papers which were reviewed. Seven articles were found to be relevant to the subject in question. Going through the references of the relevant articles, three articles were found to be directly related to the topic in study. Conclusion There is paucity of evidence to support for or against surgery in the setting of asymptomatic cervical spondylotic myelopathy despite radiographic evidence of severe stenosis. Patient factors such as age, level of activity, and risk of injury should be considered in formulating a management plan. Moreover, the patient should play an integral role in the process of decision making.
Use of the Berg Balance Scale to Predict Independent Gait After Stroke: A Study of an Inpatient Population in Japan
Authors: Makizako Hyuma , Kabe Norihito , Takano Asami , Isobe Kanako 
Published: January 2015

AbstractObjectiveTo examine whether the Berg Balance Scale (BBS) score on admission and after 1 month can be used to predict the Functional Independence Measure (FIM) walking level 6 or 7 (modified independent and independent gait respectively) after 3 months and to determine the optimal BBS cut‐off score for predicting independent gait among inpatients with first stroke in a rehabilitation facility.DesignRetrospective cohort study.SettingInpatient rehabilitation facility (Kaifukuki).ParticipantsTwo hundred fifty‐one consecutive patients with first stroke and nonindependent gait on admission.Outcome MeasuresBBS on admission and after 1 month and FIM on admission and after 3 months.ResultsArea under the receiver operating characteristic curves for predicting independent gait after 3 months were 0.81 (95% confidence interval [CI], 0.75‐0.88) for BBS score on admission; the optimal cut‐off score being ≥13 (63% sensitivity; 90% specificity). Achieving greater cut‐off score on admission was significantly associated with subsequent independent gait (odds ratio, 9.7; 95% CI, 4.38‐21.36; P < .001). A subanalysis of patients with poor balance on admission (BBS score <13; n = 191) showed area under the receiver operating characteristic curves for predicting independent gait after 3 months of 0.88 (95% CI, 0.80‐0.95) for BBS scores 1 month after admission. In this subgroup, BBS scores at 1 month of ≥27 were significantly associated with subsequent independent gait (odds ratio, 21.6, 95% CI, 6.40‐73.20; P < .001).ConclusionsAdmission BBS scores predicted FIM walking level 6 or 7, which denotes modified independent or independent gait, after 3 months, the optimal cut‐off for BBS scores being ≥13 among inpatients with first stroke in a rehabilitation facility. Patients with poor balance on admission whose BBS scores had improved to ≥27 at 1 month after admission were likely to achieve modified independent or independent gait within 3 months after admission.
Effects of Form‐Focused Training on Running Biomechanics: A Pilot Randomized Trial in Untrained Individuals
Authors: Kumar Deepak , McDermott Kelly , Feng Haojun , Goldman Veronica , Luke Anthony , Souza Richard B. , Hecht Frederick M. 
Published: January 2015

AbstractObjectiveTo investigate the changes in running biomechanics after training in form‐focused running using ChiRunning versus not‐form focused training and self‐directed training in untrained individuals.DesignPilot study‐randomized controlled trial.SettingResearch institution with tertiary care medical center.ParticipantsSeventeen subjects (9 men, 8 women) with prehypertension.MethodsTwenty‐two participants were randomized to 3 study arms but 17 completed the study. The study arms were: (1) group‐based Form‐Focused running using ChiRunning (enrolled, n = 10; completed, n = 7); (2) group‐based conventional running (enrolled, n = 6; completed, n = 4); and (3) self‐directed training with educational materials (enrolled, n = 6; completed, n = 6). The training schedule was prescribed for 8 weeks with 4 weeks of follow‐up. All subjects completed overground running motion analyses before and after training. ClinicalTrials.gov identifier for this study is NCT0158718.OutcomesAnkle, knee, hip joint peak moments, and powers; average vertical loading rate (AVLR); impact peak; cadence; stride length; strike index; and stride reach. Paired t tests were used to compare differences within groups over time.ResultsForm‐focused group reduced their Stride Reach (P = .047) after the training but not the other groups. Form‐focused group showed a close to significant reduction in knee adduction moment (P = .051) and a reduction in the peak ankle eversion moment (P = .027). Self‐directed group showed an increase in the running speed (P = .056) and increases in ankle and knee joint powers and moments.ConclusionsThere are differences in the changes in running biomechanics between individuals trained in running form that emphasizes mid‐foot strike, greater cadence, and shorter stride compared with those not trained in the these techniques. These differences may be associated with reduced lower extremity stress in individuals trained in this running form, but more studies are needed to confirm these findings in larger samples.
Development and Validation of Prognostic Indices for Recovery of Physical Functioning Following Stroke: Part 1
Authors: Bates Barbara E. , Xie Dawei , Kwong Pui L. , Kurichi Jibby E. , Cowper Ripley Diane , Davenport Claire , Vogel W. Bruce , Stineman Margaret G. 
Published: January 2015

AbstractObjectiveTo develop a prognostic index using Functional Independence Measure grades and stages that would enable clinicians to determine the likelihood of achieving a level of minimum assistance with physical functioning after a stroke. Grades define varying levels of physical function, and stages define varying levels of cognitive functioning.DesignRetrospective cohort study.SettingVeterans Affairs Medical Centers throughout the United States.ParticipantsVeterans with a diagnosis of a new stroke discharged between October 1, 2006, and September 30, 2008, who were below physical grade IV (requiring minimal assistance) at initial rehabilitation assessment.Main Outcome MeasureAchievement of physical grade IV or above at final rehabilitation assessment.ResultsPhysical grade IV was reached by 25.8% of participants who were initially below this grade. Seven variables remained independently predictive of physical grade IV after adjustment. These variables were assigned the following points: age, ≤69 years = 2, 70‐79 years = 1, ≥80 years = 0; initial physical grade, I = 0, II = 3, III = 4; initial cognitive stage, I or II = 0, III = 2, IV or V = 3, VI or VII = 4; absence of renal failure = 1; no serious nutritional compromise = 3; the type of rehabilitation services received, consultative = 0, comprehensive = 4; and recovery time between admission and discharge physical grade assessment, 1‐2 days = 0, 3‐7 days = 4, and ≥8 days = 5. The area under the receiver operating characteristic curve was 0.84 and 0.83 for the point system in the derivation and validation cohorts, respectively. The Hosmer‐Lemeshow statistic was not significant (P = .93) in the derivation cohort, indicating that the regression model demonstrated adequate fit. The proportions of patients recovered to physical grade IV in the first (score ≥9), second (score = 10‐12), third (score = 13‐15), and fourth (score >15) score quartiles were 2.72%, 11.38%, 28.96%, and 60.34%, respectively.ConclusionBy using a simple tool, clinicians can forecast the likelihood of recovery to or above the physical grade IV benchmark by the conclusion of rehabilitation services during the acute stroke hospitalization.
Trunk Muscles Activation Pattern During Walking in Subjects With and Without Chronic Low Back Pain: A Systematic Review
Authors: Ghamkhar Leila , Kahlaee Amir Hossein 
Published: January 2015

AbstractObjectiveThe purpose of this study was to identify how activity patterns of trunk muscles change in chronic LBP during walking.TypeThis was a systematic reviewLiterature SurveyELSEVIER, Pro Quest, PubMed, Google scholar and MEDLINE electronic databases were explored for the period from the earliest researchable time to August 2014. Articles investigating patients with chronic LBP and analyzing trunk muscles with surface electromyography (EMG) during walking were included.MethodologyAll studies had a case‐control design. Characteristics of the LBP patients, sample size, studied muscles and EMG parameters, and gait condition and velocity were investigated. Studies were rated as “A” to “E” (5 grades defined) based on study design and performance.ResultsMultifidus (MF), erector spinae (ES), external oblique (EO), and rectus abdominus (RA) muscle activity level were found to be increased in LBP subjects in comparison with controls. ES activity in subjects with LBP was found not to be as adaptive to walking velocity alterations as in healthy controls.ConclusionsIndividuals with chronic LBP exhibit higher global trunk muscle activity. However, the activation pattern appears to vary depending on subphases of gait. It seems that increased walking velocity challenges the stability of the spine and the control system increases muscular activation and variability level to cope with this problem. Further standardized studies with subtyped LBP cases are needed to clarify the controversial findings.
Negative outcomes in attention-deficit/hyperactivity disorder comorbid with oppositional defiant disorder
Authors: Ayaz A. B. , Ayaz M. , Kayan E. 
Published: January 2015

ObjectivesIn children and adolescents diagnosed with attention-deficit/hyperactivity disorder (ADHD), the comorbidity of the oppositional defiant disorder (ODD) negatively affects the course of ADHD. The purpose of this study was to compare ADHD-diagnosed children with and without ODD comorbidity in terms of smoking, psychoactive substance use, disciplinary punishments at school, criminal behaviors, and unintentional injuries.MethodsThis study included 109 children diagnosed with ADHD alone and 79 children with the ADHD-ODD comorbidity from a child psychiatry outpatient clinic. The children who participated in the study were aged between 6 and 15 years. Diagnoses of the children were determined by child psychiatrists according to DSM-IV criteria, and the Turgay DSM-IV-based Child and Adolescent Behavior Disorders Screening and Rating Scale-Parents Form was used to support the diagnosis in initial evaluations of children. Forty-six to fifty months after the first admission, parents were questioned regarding all negative outcomes from the time of first diagnosis to the time of the evaluation by phone.ResultsThe groups were compared in terms of smoking, psychoactive substance use, disciplinary punishments at school, criminal behaviors, and unintentional injuries over a period of 4 years. The ODD-ADHD group was determined to have higher rates of disciplinary punishments at school, smoking, and unintentional injuries compared with the ADHD group. No statistically significant difference was found between the two groups in terms of criminal behaviors and psychoactive substance use.ConclusionsThe ODD comorbidity increases the risk of negative outcomes in children diagnosed with ADHD.
Direct measurement of thrust and efficiency of an airfoil undergoing pure pitching
Authors: Mackowski A. W. , Williamson C. H. K. 
Published: January 2015

AbstractWe experimentally investigate the thrust and propulsive efficiency of a NACA 0012 airfoil undergoing oscillating pitching motion at a Reynolds number of $1.7\times 10^{4}$. While previous studies have computed thrust and power indirectly through measurements of momentum deficit in the object’s wake, we use a pair of force transducers to measure fluid forces directly. Our results help solidify a variety of experimental, theoretical and computational answers to this classical problem. We examine trends in propulsive performance with flapping frequency, amplitude and Reynolds number. We also examine the measured unsteady forces on the airfoil and compare them with linear theory dating from the first half of the 20th century. While linear theory significantly overpredicts the mean thrust on the foil, its prediction for the amplitude and phase of the time-varying component is surprisingly accurate. We conclude with evidence that the thrust force produced by the pitching airfoil is largely insensitive to most wake vortex arrangements.