bluuebunny/crossref_metadata_2025 huggingface dataset:
Current reclamation practices after oil and gas development do not speed up succession or plant community recovery in big sagebrush ecosystems in Wyoming
Authors: Rottler Caitlin M. , Burke Ingrid C. , Palmquist Kyle A. , Bradford John B. , Lauenroth William K.
Published: July 2017

Reclamation is an application of treatment(s) following disturbance to promote succession and accelerate the return of target conditions. Previous studies have framed reclamation in the context of succession by studying its effectiveness in reestablishing late‐successional plant communities. Reestablishment of plant communities is especially important and challenging in drylands such as shrub steppe ecosystems where succession proceeds slowly. These ecosystems face threats from climate change, invasive species, altered fire regimes, and land‐use change, as well as fossil‐fuel extraction and associated disturbance. As such, the need for effective reclamation after this type of energy development is great. However, past research regarding this type of reclamation has focused on mining rather than oil and gas development. To better understand the effect of reclamation on rates of succession in dryland shrub steppe ecosystems, we sampled oil and gas wellpads and adjacent undisturbed big sagebrush plant communities in Wyoming, U.S.A., and quantified the extent of recovery for forbs, grasses, and shrubs on reclaimed and unreclaimed wellpads relative to undisturbed plant communities. Reclamation increased the recovery rate for early‐successional types, including combined forbs and grasses and perennial grasses, but did not affect recovery rate of late‐successional types, particularly big sagebrush and perennial forbs. Rather, subsequent analyses showed that recovery of late‐successional types was affected by soil texture and time since wellpad abandonment. This is consistent with studies in other ecosystems where reclamation has been implemented, suggesting that reclamation may not help reestablish late‐successional plant communities more quickly than they would reestablish naturally.
The Production Life Cycle
Authors: Li Ben G. , Liu Yibei
Published: July 2017

Tasks in production have different dynamics from individuals products. We build a general equilibrium model where three forces (i.e., offshoring, learning, and wage) interact to determine how production fragmentation evolves over time. We show that the production process follows a life cycle: its fragmentation emerges, deepens, and converges. Our model is stylized and versatile, and it can be used to tractably characterize the loci of global output, productivity, welfare, and value‐added distribution as production fragmentation progresses.
microRNA159‐targetedSlGAMYBtranscription factors are required for fruit set in tomato
Authors: da Silva Eder Marques , Silva Geraldo Felipe Ferreira e , Bidoia Débora Brussolo , da Silva Azevedo Mariana , de Jesus Frederico Almeida , Pino Lilian Ellen , Peres Lázaro Eustáquio Pereira , Carrera Esther , López‐Díaz Isabel , Nogueira Fabio Tebaldi Silveira
Published: July 2017

The transition from flowering to fruit production, namely fruit set, is crucial to ensure successful sexual plant reproduction. Although studies have described the importance of hormones (i.e. auxin and gibberellins) in controlling fruit set after pollination and fertilization, the role of microRNA‐based regulation during ovary development and fruit set is still poorly understood. Here we show that the microRNA159/GAMYB1and‐2pathway (the miR159/GAMYB1/2module) is crucial for tomato ovule development and fruit set. MiR159 andSlGAMYBswere expressed in preanthesis ovaries, mainly in meristematic tissues, including developing ovules.SlMIR159‐overexpressing tomato cv. Micro‐Tom plants exhibited precocious fruit initiation and obligatory parthenocarpy, without modifying fruit shape. Histological analysis showed abnormal ovule development in such plants, which led to the formation of seedless fruits.SlGAMYB1/2silencing inSlMIR159‐overexpressing plants resulted in misregulation of pathways associated with ovule and female gametophyte development and auxin signalling, includingAINTEGUMENTA‐likegenes and the miR167/SlARF8amodule. Similarly toSlMIR159‐overexpressing plants,SlGAMYB1was downregulated in ovaries of parthenocarpic mutants with altered responses to gibberellins and auxin.SlGAMYBslikely contribute to fruit initiation by modulating auxin and gibberellin responses, rather than their levels, during ovule and ovary development. Altogether, our results unveil a novel function for the miR159‐targetedSlGAMYBsin regulating an agronomically important trait, namely fruit set.
Clinical and pathological classification of canine intraocular lymphoma
Authors: Lanza Matthew R. , Musciano Ayla R. , Dubielzig Richard D. , Durham Amy C.
Published: July 2017

The objectives of this retrospective study of 100 dogs with intraocular lymphoma were to describe the histomorphologic and immunohistochemical features of canine intraocular lymphoma, determine the proportion of cases with presumed solitary ocular lymphoma (PSOL) compared to multicentric disease, and assess the clinical outcomes of these patients. Selected cases from Penn Vet Diagnostic Laboratory and Comparative Ocular Pathology Lab of Wisconsin (2004–2015) were evaluated and subtyped using the WHO classification system. Peripheral T‐cell lymphoma and diffuse large B‐cell lymphoma were the two most common subtypes. Questionnaires were distributed to the referring veterinarians and veterinary ophthalmologists inquiring about clinical signs at time of enucleation, staging, patient outcome, treatment, and disease progression. Cases were categorized as PSOL if only ocular involvement was noted at the time of diagnosis based on the clinical staging criteria. The majority of cases (61%) did not have systemic involvement at the time of diagnosis, and these cases did not progress postoperatively. Median survival time (MST) was significantly higher for the presumed solitary intraocular cases: 769 vs. 103 days, hazard ratio of 0.23 (95% CI: 0.077–0.68). The subtype of lymphoma did not affect survival time. The results of this study suggest two significant points of clinical interest: the majority of dogs (61%) presented without signs of systemic involvement of lymphoma at the time of enucleation, and dogs with only ocular involvement showed no disease progression postenucleation.
Analysis of Divided Policy and Its Impact on Shareholders Wealth Maximization in Nigerian Firms (A Study of Brewery Industry)
Authors: Omodero Cordelia Onyinyechi , Amah Kalu Ogbonnaya
Published: July 2017

The study evaluated dividend policy and measured its impact on shareholders’ wealth maximization in Nigerian firms (a study of brewery industry). A cross-survey research design was adopted and secondary data extracted from the published annual reports of the firms studied. The statistical tool used was a multi-regression analysis and t-test for hypotheses testing and data analysis with the aid of SPSS version 20. The result in Guinness Nigeria Plc., indicated the irrelevance of dividend policy. From the result, the DPS, EPS and NAPS which were the explanatory variables, had no positive impact on the market value per share (MPS) both collectively and individually. The result from Nigeria Breweries Plc., proved dividend policy is relevant to an extent to which earnings per share and net asset per share are positively affected. The F-ratio was 0.000 which shows a significant positive impact on the MPS. The earnings per share and net asset per share were also significant except the dividend per share which had no impact on the market value per share. The implication is that the growth in stock prices is not always a function of dividend payment.
Failure Modes in Hybrid Titanium Composite Laminates
Authors: Reiner Johannes , Veidt Martin , Dargusch Matthew
Published: July 2017

Hybrid titanium composite laminates (HTCLs) combine the benefits of thin titanium sheets and fiber-reinforced polymer (FRP) composite laminates to design high performance light-weight materials with optimized impact resistance, fracture toughness, durability, and/or thermal performance. This paper starts with a detailed review of typical failure modes observed in HTCLs. The critical manufacturing process of thin grade II titanium sheets combined with HexPly G947/M18 carbon fiber-reinforced polymer laminates is described in detail. This includes the evaluation of titanium surface preparation techniques, which guarantee good adhesive bonding. A systematic experimental study of different HTCL configurations under tensile loading confirms that the major failure modes are debonding between the titanium sheet and the FRP laminate, matrix cracking in the 90 deg plies of the FRP laminate and interlaminar delamination. The results show that HTCLs made from woven carbon FRP plies show higher ultimate strengths and strain at breaks than HTCLs containing a cross-ply composite core made from unidirectional (UD) prepreg.
URANS Models for the Simulation of Full Load Pressure Surge in Francis Turbines Validated by Particle Image Velocimetry
Authors: Decaix J. , Müller A. , Favrel A. , Avellan F. , Münch C.
Published: July 2017

Due to the penetration of alternative renewable energies, the stabilization of the electrical power network relies on the off-design operation of turbines and pump-turbines in hydro-power plants. The occurrence of cavitation is however a common phenomenon at such operating conditions, often leading to critical flow instabilities which undercut the grid stabilizing capacity of the power plant. In order to predict and extend the stable operating range of hydraulic machines, a better understanding of the cavitating flows and mainly of the transition between stable and unstable flow regimes is required. In the case of Francis turbines operating at full load, an axisymmetric cavitation vortex rope develops at the runner outlet. The cavity may enter self-oscillation, with violent periodic pressure pulsations. The flow fluctuations lead to dangerous electrical power swings and mechanical vibrations, dictating an inconvenient and costly restriction of the operating range. The present paper reports an extensive numerical and experimental investigation on a reduced scale model of a Francis turbine at full load. For a given operating point, three pressure levels in the draft tube are considered, two of them featuring a stable flow configuration and one of them displaying a self-excited oscillation of the cavitation vortex rope. The velocity field is measured by two-dimensional (2D) particle image velocimetry (PIV) and systematically compared to the results of a simulation based on a homogeneous unsteady Reynolds-averaged Navier–Stokes (URANS) model. The validation of the numerical approach enables a first comprehensive analysis of the flow transition as well as an attempt to explain the onset mechanism.
Modeling Coupled Conduction–Convection Ice Formation on Horizontal Axially Finned and Unfinned Tubes
Authors: Al-Sarrach Hassan M. S. , Kahwaji Ghalib Y. , Samaha Mohamed A.
Published: July 2017

The freezing of water around immersed unfinned and finned horizontal tubes is simulated numerically. The impact of natural convection as well as the water density inversion with temperature is considered. The equations governing both fluid flow and heat transfer around the tubes and through the solid–liquid interface are solved using finite difference schemes. To follow the moving solid–liquid boundary, dynamic grid generation is performed using the elliptic partial differential equation method with iterative interpolating smoothing to avoid divergence. For validation, the present results for unfinned tubes are compared with experimental studies reported in the literature. The present numerical simulations are aimed at improving our understanding of the parameters affecting the freezing process around both finned and unfinned tubes. The results showed that the flow patterns are similar in both tube configurations with one main vortex in the liquid region when there is no inversion in the water density. The presence of fins complicates the distribution of local Nusselt number along the solid–liquid interface in comparison with the unfinned tube. The impact of natural convection on the rate of ice formation is limited to the initial period of the freezing process. The results also show the freezing enhancement when utilizing fins. An accumulated ice mass correlation is developed for each tube configuration. This model can be used to optimize the design of both finned and unfinned tubes in energy storage systems, which are viable tools for air conditioning load shifting and leveling.
Toward a Universal Roughness Correlation
Authors: Forooghi Pourya , Stroh Alexander , Magagnato Franco , Jakirlić Suad , Frohnapfel Bettina
Published: July 2017

The effects of several surface parameters on equivalent sand roughness (ks) in fully rough regime are investigated by means of direct numerical simulation (DNS) of flow in channels with different wall geometries at Reτ≅500. The roughness geometry is generated by randomly distributing roughness elements of random size and prescribed shape on a flat surface. The roughness generation approach allows systematic variation of moments of surface height probability density function (PDF), size distribution of roughness peaks, and surface slope. A total number of 38 cases are solved. It is understood that a correlation based on surface height skewness and effective slope (ES) can satisfactorily predict ks normalized with maximum peak-to-valley roughness height within a major part of the studied parameter space. Such a correlation is developed based on the present data points and a number of complementary data points from the literature. It is also shown that the peak size distribution can independently influence the skin friction; at fixed values of rms surface height, skewness, kurtosis, and ES, a surface with uniform size peaks causes higher skin friction compared to one with nonuniform peak sizes. Additionally, it is understood that a roughness generated by regular arrangement of roughness elements may lead to a significantly different skin friction compared to a random arrangement. A staggered and an aligned regular arrangement are examined in this paper and it is observed that the former produces significantly closer results to the corresponding random arrangement.
A New Dynamic Model of Coupled Axial–Torsional Vibration of a Drill String for Investigation on the Length Increment Effect on Stick–Slip Instability
Authors: Hosseinzadeh Ali , Bakhtiari-Nejad Firooz
Published: July 2017

In this paper, a new model is proposed to study the coupled axial–torsional vibration of the drill string. It is assumed that rotary table angular speed is constant and equals to the nominal angular speed of the drill string. In addition, axial displacement of any point on the drill string is considered to be as the sum of rigid-body motion and elastic vibrations. The depth of cut is defined using instantaneous dynamic states instead of using the delayed model as presented in previous researches. A velocity-weakening function is introduced for modeling the behavior of the frictional component of the torque-on-bit (TOB) with respect to the bit angular speed. After discretizing vibration equations, stability analysis of the system is investigated by linearizing the nonlinear system around its steady-state response point. Considering nominal weight-on-bit (WOB) (W0) and nominal rotational speed (Ω) as the input parameters of the drilling, variation of maximum allowable value of (W0) is presented with respect to variation of Ω . It is shown that the maximum allowable value of W0 has an increasing–decreasing behavior with respect to Ω. The effect of drill string upper and lower part lengths is studied on the stability of the system, and practical results are presented both in the condition that W0 is constant and in the condition that the hook upward force is constant. It is shown that by increasing the drill string length, the system is more exposed to instability, and this must be considered in regulating the input parameters of drilling.
Experimental Study on Complex Modes of an End-Damped Continuous Beam
Authors: Xing Xing , Feeny Brian F.
Published: July 2017

The complex modes of an end-damped cantilevered beam are studied as an experimental example of a nonmodally damped continuous system. An eddy-current damper is applied, for its noncontact and linear properties, to the end of the beam, and is then characterized to obtain the effective damping coefficient. The state-variable modal decomposition (SVMD) is applied to extract the modes from the impact responses in the cantilevered beam experiments. Characteristics of the mode shapes and modal damping are examined for various values of the end-damper damping coefficient. The modal frequencies and mode shapes obtained from the experiments have a good consistency with the results of the finite element model. The variation of the modal damping ratio and modal nonsynchronicity with varying end-damper damping coefficient also follow the prediction of the model. Over the range of damping coefficients studied in the experiments, we observe a maximum damping ratio in the lowest underdamped mode, which correlates with the maximum modal nonsynchronicity. Complex orthogonal decomposition (COD) is applied in comparison to the modal identification results obtained from SVMD.
Functional response of two Neoseiulus species preying on Tetranychus urticae Koch
Authors: Zheng Yuan , De Clercq Patrick , Song Zi-Wei , Li Dun-Song , Zhang Bao-Xin
Published: July 2017

Neoseiulus californicus and N. cucumeris are both potential candidates for the biological control of key pests in China. Whereas N. californicus has mainly been used to control spider mites, N. cucumeris has been released for the control of thrips and spider mites. To understand the potential of the combined use of N. californicus and N. cucumeris to suppress outbreaks of Tetranychus urticae, the predatory performance of these Neoseiulus species against different stages of T. urticae, either separately or in combination, was evaluated by assessing their functional responses in the laboratory. The values of the attack rate coefficient (α) of N. californicus to each stage of T. urticae exceeded those of N. cucumeris, whereas the handling time (Th) of N. californicus was longer than that of N. cucumeris, except when attacking the larvae of T. urticae. Especially at the higher prey densities, N. cucumeris consumed more eggs per day than N. californicus, whereas N. californicus consumed more larvae. Both predators killed similar numbers of nymphs at each density when tested singly. The searching efficiency of the Neoseiulus species decreased with increasing prey densities, and for all stages of T. urticae, the searching efficiency of the Neoseiulus species tested singly was lower than when they were tested together. The study indicates the potential of mixed releases of N. californicus and N. cucumeris for the management of spider mite infestations.
Effects of Practice on the Control of Whole-Body Momentum in Active Children and Adults
Authors: Cesar Guilherme M. , Lewthwaite Rebecca , Sigward Susan M.
Published: July 2017

The purpose of this study was to determine the effects of practice on performance of a running task requiring maximal speed and accurate termination. Physically active pre-pubertal boys and men ran as fast as possible and stopped at a pre-determined target location. Twenty-five trials were collected and comparisons made between first five (early) and last five (late) trials. Approach velocity, normalized approach velocity (percent of maximal sprint velocity, %Vmax), stopping distance from target, and success rate were calculated. Self-efficacy for task performance and fatigue reports were collected prior to trials. Children ran more slowly than adults in absolute terms but performed at higher relative velocity. Both groups displayed similar accuracy and percentages of successful trials across early and late practice. Adults increased approach velocity and %Vmax from early to late; children, already higher in relative maximal velocity, did not change. Self-efficacy paralleled performance findings and correlated with %Vmax and success rate; both groups reported higher self-efficacy for late compared with early. With practice, adults increased approach velocity and children did not; however, children appeared to be performing at a higher relative level from the beginning, perhaps reflecting their more substantial recent histories of similar physical activity and limiting further effects of practice.
Effectiveness of PRP Injection in Reducing Recovery Time of Acute Hamstring Injury: A Critically Appraised Topic
Authors: Manduca Mary Lynn , Straub Stephen J.
Published: July 2017

Clinical Scenario: Hamstring strains are common athletic injuries, with a high-recurrence rate (34%). Recently, platelet-rich plasma (PRP) injections have gained popularity as a potential treatment option to accelerate healing of hamstring injury. Focused Clinical Question: Does the combination of PRP injection and rehabilitation decrease recovery time of acute hamstring injury as compared to rehabilitation alone in college athletes? Summary of Key Findings: A literature search resulted in 3 randomized controlled trials. One study showed benefits in various outcome measures with PRP, compared to rehabilitation alone, while 2 showed no benefits. One study reported improved pain, ultrasonography regenerative indications, and recovery time with PRP injection following acute hamstring injury; however, larger studies have shown no benefits. The literature demonstrates conflicting evidence regarding benefits of PRP injections in hamstring injuries. Clinical Bottom Line: At this time, PRP injections cannot be recommended as having value for hamstring injuries, compared to rehabilitation alone. Strength of Recommendation: Due to inconsistent or limited quality patient-oriented evidence in existing literature, the strength of this recommendation is grade B, based on the strength of recommendation taxonomy.
The Relationship Between Hip Strength and the Y Balance Test
Authors: Wilson Benjamin R. , Robertson Kaley E. , Burnham Jeremy M. , Yonz Michael C. , Ireland Mary Lloyd , Noehren Brian
Published: July 2017

Context: The Y Balance Test was developed as a test of dynamic postural control and has been shown to be predictive of lower-extremity injury. However, the relationship between hip strength and performance on the Y Balance Test has not been fully elucidated. Objective: The goal of this study was to identify the relationship between components of isometric hip strength and the Y Balance Test, to provide clinicians better guidance as to specific areas of muscle performance to address in the event of poor performance on the Y Balance Test. Design: Laboratory study. Setting: Biomechanics laboratory. Participants: A total of 73 healthy participants (40 males and 33 females) volunteered for this study. Intervention: None. Main Outcome Measures: Participants completed the Y Balance Test on the right leg. The authors then measured peak isometric torque in hip external rotation, abduction, and extension. Correlations were calculated between torque measurements, normalized for mass and Y Balance Test performance. Significant relationships were used in linear regression models to determine which variables were predictive of the Y Balance Test performance. Results: The authors found significant positive correlations between Y Balance Test performance and hip abduction strength. They also found correlations between the Y Balance Test and hip extension and external rotation strengths. Linear regression analysis showed hip abduction to be the only significant predictor of Y Balance performance. Conclusions: The authors found the strongest association between the Y Balance Test and hip abduction strength. They also showed smaller but significant associations with hip extension and external rotation strength. When entered into a linear regression analysis, hip abduction strength was the only significant predictor of Y Balance performance. Using this information, practitioners should look to hip abduction strength when patients exhibit deficits in the Y Balance Test.
The Influence of Verbal and Tactile Feedback on Electromyographic Amplitude of the Shoulder Musculature During Common Therapeutic Exercises
Authors: Jones Sean A. , Pamukoff Derek N. , Mauntel Timothy C. , Blackburn J. Troy , Myers Joseph B.
Published: July 2017

Context: Verbal and tactile feedback (VTF) during rehabilitation exercises can increase muscle activation, thus improving the therapeutic benefits. However, it is unclear which feedback method elicits the greatest electromyographic (EMG) amplitude. Objective: To determine if the addition of tactile to verbal feedback (VF) increases EMG amplitude of selected shoulder musculature during scapular plane elevation (Ys), shoulder horizontal abduction with external rotation (Ts), and scapular retraction with external rotation (Ws). Design: Repeated-measures cross-over design. Setting: Biomechanics laboratory. Participants: A total of 30 physically active adults volunteered for this study—age = 20.23 (1.25) years; height = 1.71 (0.073) m; and mass = 70.11 (15.14) kg. Interventions: Electromyography of the serratus anterior; upper, middle, and lower trapezii; and anterior and posterior deltoids was recorded during Ys, Ts, and Ws with VTF and VF alone during separate testing sessions. Participants completed baseline trials without feedback, then received VTF and VF across 2 counterbalanced sessions. Main Outcome Measures: Difference scores were calculated between prefeedback and postfeedback interventions, and the difference score between baseline measurements was used as a control. One-way analysis of variance of the difference scores was used to evaluate the influence of VTF and VF on EMG amplitude during Ys, Ts, and Ws. Results: There was a significant difference between conditions for EMG amplitude of the middle trapezius (F2,28 = 4.09, P = .02) and serratus anterior (F2,28 = 3.91, P = .03) during Ys, the middle trapezius (F2,28 = 7.82, P = .001) during Ws, and the upper (F2,28 = 3.61, P = .03) and middle trapezii (F2,28 = 5.81, P = .01) during Ts. Post hoc testing revealed that both feedback conditions elicited greater EMG amplitude compared with no feedback, but there were no significant differences between the feedback conditions. Conclusions: The addition of tactile feedback to VF does not increase EMG amplitude compared with VF alone. This study indicates that feedback, regardless of type, is more beneficial than providing no feedback, for increasing EMG amplitude.
Effect of Acute Static Stretching on Lower Limb Movement Performance Using STABL Virtual Reality System
Authors: Ameer Mariam A. , Muaidi Qassim I.
Published: July 2017

Context: The effect of acute static stretching (ASS) on the lower limb reaction time (RT) has been recently questioned to decrease the risk of falling and injuries in situations requiring a rapid reaction, as in the cases of balance disturbance. Objective: The main purpose of this study was to detect the effect of ASS on the lower limb RT using a virtual reality device. Design: Two-group control group design. Setting: Research laboratory. Participants: The control and experimental groups were formed randomly from 60 female university students. Intervention: Each participant in the experimental group was tested before and after ASS for the quadriceps, hamstrings, and planter flexor muscles, and compared with the control group with warming-up exercise alone. The stretching program involved warming up in the form of circular running inside the lab for 5 minutes followed by stretching of each muscle group three times, to the limit of discomfort of 45 seconds, with resting period of 15 seconds between stretches. Main Outcome Measures: The measurements included the RT of the dominant lower-extremity using the dynamic stability program STABL Virtual Reality System (model no. DIZ 2709; Motekforce Link). Results: There was a statistically significant reduction (F = 162, P < .05) in posttest RT between the 2 groups and significant decrease in RT after stretching in the experimental group (7.5%; P < .05). Conclusion: ASS of the lower limb muscles tends to decrease the lower limb RT and improve movement performance.
Working as a Sport Psychology Practitioner in Professional Cricket: Challenges, Experiences, and Opportunities
Authors: Cotterill Stewart
Published: July 2017

While there have been increasing opportunities for sport psychology practitioners in cricket, there are concerns regarding employment practices in the field and the knock-on impact on the practitioners. The aim of this research was to explore the experiences, reflections, challenges, and opportunities perceived by practitioners regarding their own roles delivering sport psychology in elite cricket. Participants were 12 sport psychology practitioners (8 male and 4 female) purposively selected based on their experience working in cricket. Participants were interviewed to gain an understanding of their experiences working as sport psychology practitioners. The data were thematically analyzed, resulting in the emergence of 7 higher order themes: the role, perceptions of the psychologist, consultation approach, limiting factors, first-team environment, challenges faced, and proposed changes. Results suggest that there are similarities in the challenges experienced across professional clubs and at different levels in cricket. Broader challenges for the clubs, the national governing body, and the sport psychology profession also emerged.
Effects of a Motivational Self-Talk Intervention for Endurance Athletes Completing an Ultramarathon
Authors: McCormick Alister , Meijen Carla , Marcora Samuele
Published: July 2017

This study examined the effects of strategic, motivational self-talk for runners completing a 60-mile, overnight ultramarathon using a randomized, controlled experiment. Data were collected before, during, and after an annual ultramarathon. Twenty-nine ultramarathon runners were randomly allocated to a motivational self-talk group or an alternative control group. A condition-by-time mixed ANOVA indicated that learning to use motivational self-talk did not affect preevent self-efficacy or perceived control. A t-test and magnitude-based inference indicated that motivational self-talk did not affect performance. Nevertheless, follow-up data suggested that most participants found the intervention helpful and continued to use it six months after their research commitment, particularly in endurance events and to a lesser extent in training. Participants continued to use self-talk to cope with exertion, as well as other stressors such as blister discomfort and adverse conditions. Suggestions are offered for future research examining the effects of psychological interventions on performance in endurance events.
Chewing-induced facial dystonia: a rare presentation of task-specific dystonia
Authors: Sharma Chandramohan , Kumawat Banshi Lal , Garg Ankur , Kumar Rana Kaushik
Published: July 2017

This case is an addition to scarce literature available for a rare condition, chewing-induced task-specific dystonia. The patient was a 63-year-old woman who presented with a 4-year history of progressive difficulty in eating food only during chewing associated with abnormal facial grimaces without any difficulty in drinking, swallowing, speaking or singing. Examination revealed dystonia of facial muscles every time she chewed but absent during drinking and speaking. As movements were consistent and reproducible with the specific task, other differential diagnosis like motor tics, psychogenic disorder, tardive dystonia and parkinsonism syndrome were excluded leading to a diagnosis of task-specific facial dystonia triggered by chewing. Treatment was started with trihexyphenidyl and later on tetrabenazine was also added but she got only mild relief of symptoms. As she did not agreed for botulinum toxin therapy, so we continued with the same treatment without much improvement.
Metabolomic biomarkers of concussion
Authors: Paxman Eric James , Wanner Zachary , Boora Jyote , Douglas Kiss , Metz Gerlinde , Montina Tony , Debert Chantel
Published: July 2017

Objective

To determine if1H NMR spectroscopy of urine and a quantitative metabolomics approach can aid diagnostic and prognostic outcomes in patients who have suffered acute sport concussion.

Design

Pre-concussion urine samples were collected from WinSport athletes at the beginning of the sport season. Any athlete who experienced a head injury reported to a brain injury clinic to be tested within 72 hours of head injury. This testing included collection of a post-concussion urine sample for metabolomic analysis.

Setting

Brain injury clinic and metabolomics laboratory.

Participants

167 athletes entered the study with a total of 39 concussions occurring. Inclusion criteria: at least 18 years old, diagnosis of concussion, and concussion sustained within 72 hours. Exclusion criteria: multiple injuries coinciding with concussion and a past history of neurological pathology.

Outcome measures

Metabolite concentrations were calculated in pre- and post-concussion urine samples and compared using a paired t-test and partial least squares discriminant analysis (PLS-DA) to determine which metabolites led to significant variation between samples.

Main results

The PLS-DA model showed significant variation between baseline and post-injury sample groups and passed all permutation and cross-validation testing. A paired t-test, with cross-validation, isolated five significant metabolites of interest in the concussion group (p<0.05).

Conclusions

Using NMR spectroscopy we quantified urinary metabolites in patients before and after concussion. This revealed several metabolites that were shown to be significantly altered following injury, opening up future inquiry into both the pathways and processes involved in concussion and new avenues for personalized diagnosis and treatment.

Competing interests

None.
The role of environmental factors for the onset of restricted mobility outside the home among older adults with osteoarthritis: a prospective cohort study
Authors: Rantakokko Merja , Wilkie Ross
Published: July 2017

Objectives

The study examines how environmental factors contribute to the onset of restricted mobility outside the home among older adults with osteoarthritis.

Methods

This is a prospective cohort study of adults aged 50 years and older with osteoarthritis (n=1802). Logistic regression tested the association between the onset of restricted mobility outside the home and health, sociodemographic and perceived environmental barriers (hills and steep slopes, inaccessible public buildings, poor pavement condition, lack of access to public parks or sport facilities, heavy traffic or speeding cars and poor weather). The potential moderating role of environmental barriers on the association between health factors and onset was examined using interaction terms and stratified analysis.

Results

Of 1802 participants, 13.5% (n=243) reported the onset of restricted mobility outside the home at 3-year follow-up. Walking disability, anxiety, depression, cognitive impairment and obesity and all environmental barriers were associated with onset after adjustment for confounders. Environmental barriers had an added contribution to the effect of the health conditions on onset of restricted mobility, which was attenuated when adjusted for confounders. The added contribution remained only for walking disability and the presence of hills and steep slopes; in the presence of both, the association with onset of restricted mobility was stronger (OR 7.66, 95% CI 4.64 to 12.64) than in the presence of walking disability (3.60, 2.43 to 5.32) or the presence of hills and steep slopes alone (4.55, 2.89 to 7.16).

Conclusion

For older adults with osteoarthritis, environmental barriers are associated and add a contribution to that of morbidities and walking disability on the onset of restricted mobility outside the home. Awareness of environmental barriers is important when aiming to maintain mobility and activities outside the home despite health conditions in older adults.
Epidemiology and risk factors of coronary artery aneurysm in Taiwan: a population based case control study
Authors: Fang Chein-Tang , Fang Yi-Ping , Huang Yaw-Bin , Kuo Chen-Chun , Chen Chung-Yu
Published: July 2017

Objectives

Coronary artery aneurysm (CAA) is usually an asymptomatic and rare disease. There are limited epidemiological data for CAA in Asian populations and in the rest of the world.

Design

A retrospective case control study.

Setting

A population based, database study from Taiwan's National Health Insurance Research Database, between 2005 and 2011.

Participants

CAA patients identified using International Classification of Diseases, ninth revision, clinical modification (ICD-9-CM) code 414.11 with CAA examinations.

Outcome measures

The incidence rate and mortality rate of CAA were calculated. We also matched patients with non-CAA patients according to age, gender and index year at a 1:10 ratio to explore the risk factors for CAA using conditional logistic regression.

Result

A total of 1397 CAA patients were identified between 2005 and 2011; 41.9% were paediatric patients and 58.1% were adults. The incidence rate and mortality rate of CAA in Taiwan were 0.87 and 0.05 per 105person-years, respectively. The adjusted odds ratios (aOR) for coronary atherosclerosis, hypertension, dyslipidaemia and diabetes were 7.97, 2.09, 2.48 and 1.51, respectively. Of note, aortic dissection (aOR 6.76), aortic aneurysm (aOR 5.82) and systemic lupus erythematosus (aOR 4.09) were found to be significantly associated with CAA.

Conclusion

In Taiwan, CAA patients were distributed across both paediatric and adult populations. Apart from cardiovascular risk factors, aortic diseases and systemic lupus erythematosus need to be investigated further in CAA patients.
Association of prehypertension and cardiovascular risk factor clustering in Inner Mongolia: a cross-sectional study
Authors: Li Guoju , Guo Guanghong , Wang Wenrui , Wang Ke , Wang Hailing , Dong Fen , Qian Yonggang , Gong Haiying , Xu Guodong , Li Yanlong , Pan Li , Zhang Biao , Shan Guangliang
Published: July 2017

Objectives

To assess the clustering of cardiovascular disease (CVD) risk factors in Han and Mongolian adults with prehypertension or hypertension in Northern China.

Methods

We selected 3227 Han and Mongolian participants (20–80 years old) using a multistage cluster sampling method in 2014. The participants were interviewed by standard questionnaires and underwent anthropometric measurement and biochemical testing. Han and Mongolian participants were divided into optimal, prehypertension, and hypertension groups based on blood pressure. A multinomial logit analysis was performed to explore relationships between CVD risk factor clustering and prehypertension or hypertension, and the heterogeneity between Han and Mongolian was evaluated by the Cochran Q test. The differences between the ethnic groups in the proportions of risk factors was tested with the χ2test.

Results

The clustering of two or three CVD risk factors in the prehypertension or hypertension groups was consistently higher than in the optimal group (Bonferroni, p<0.0167). The odds ratios (ORs) of prehypertension and hypertension increased with the number of CVD risk factors (ptrend<0.0001). In multivariate modelling, the adjusted ORs of one, two, and ≥3 CVD risk factors versus no risk factors was, respectively, 1.95, 2.25, and 2.28 in Han prehypertensive participants, and 1.73, 2.83, and 3.69 in Mongolian prehypertensive participants. In addition, the adjusted ORs were 3.15, 4.75, and 6.49 in Han hypertensive participants, and 1.90, 5.29, and 8.13 in Mongolian hypertensive participants (all p<0.05). There was no significant heterogeneity between Han and Mongolian participants in the prehypertension or hypertension groups. The age-standardised prevalence of ≥3 risk factors was 38.30% in Han men and 39.79% in Mongolian men. The rate was significantly lower in Han women than Mongolian women (9.18% vs 14.55%, p=0.002).

Conclusions

These findings showed clustering of CVD risk factors in prehypertensive Han and Mongolian adults, and showed prehypertension may be a useful target for intervention.
Associations between maternal size and health outcomes for women undergoing caesarean section: a multicentre prospective observational study (The MUM SIZE Study)
Authors: Dennis Alicia Therese , Lamb Karen Elaine , Story David , Tew Michelle , Dalziel Kim , Clarke Philip , Lew Jospeh , Parker Anna , Hessian Elizabeth , Teale Gyln , Simmons Scott , Casalaz Dan
Published: July 2017

Objectives

To investigate associations between maternal body mass index (BMI) at delivery (using pregnancy-specific BMI cut-off values 5 kg/m2higher in each of the WHO groups) and clinical, theatre utilisation and health economic outcomes for women undergoing caesarean section (CS).

Design

A prospective multicentre observational study.

Setting

Seven secondary or tertiary referral obstetric hospitals.

Participants

One thousand and four hundred and fifty-seven women undergoing all categories of CS.

Data collection

Height and weight were recorded at the initial antenatal visit and at delivery. We analysed the associations between delivery BMI (continuous and pregnancy-specific cut-off values) and total theatre time, surgical time, anaesthesia time, maternal and neonatal adverse outcomes, total hospital admission and theatre costs.

Results

Mean participant characteristics were: age 32 years, gestation at delivery 38.4 weeks and delivery BMI 32.2 kg/m2. Fifty-five per cent of participants were overweight, obese or super-obese using delivery pregnancy-specific BMI cut-off values. As BMI increased, total theatre time, surgical time and anaesthesia time increased. Super-obese participants had approximately 27% (17 min, p<0.001) longer total theatre time, 20% (9 min, p<0.001), longer surgical time and 40% (11 min, p<0.001) longer anaesthesia time when compared with normal BMI participants. Increased BMI at delivery was associated with increased risk of maternal intensive care unit admission (relative risk 1.07, p=0.045), but no increased risk of neonatal admission to higher acuity care. Total hospital admission costs were 15% higher in super-obese women compared with normal BMI women and theatre costs were 27% higher in super-obese women.

Conclusions

Increased maternal BMI was associated with increased total theatre time, surgical and anaesthesia time, increased total hospital admission costs and theatre costs. Clinicians and health administrators should consider these clinical risks, time implications and financial costs when managing pregnant women.
Barriers and facilitators to adherence to secondary stroke prevention medications after stroke: analysis of survivors and caregivers views from an online stroke forum
Authors: Jamison James , Sutton Stephen , Mant Jonathan , Simoni Anna De
Published: July 2017

Objective

To identify barriers and facilitators of medication adherence in patients with stroke along with their caregivers.

Design

Qualitative thematic analysis of posts about secondary prevention medications, informed by Perceptions and Practicalities Approach.

Setting

Posts written by the UK stroke survivors and their family members taking part in the online forum of the Stroke Association, between 2004 and 2011.

Participants

84 participants: 49 stroke survivors, 33 caregivers, 2 not stated, identified using the keywords ‘taking medication’, ‘pills’, ‘size’, ‘side-effects’, ‘routine’, ‘blister’ as well as secondary prevention medication terms.

Results

Perceptions reducing the motivation to adhere included dealing with medication side effects, questioning doctors’ prescribing practices and negative publicity about medications, especially in regard to statins. Caregivers faced difficulties with ensuring medications were taken while respecting the patient’s decisions not to take tablets. They struggled in their role as advocates of patient’s needs with healthcare professionals. Not experiencing side effects, attributing importance to medications, positive personal experiences of taking tablets and obtaining modification of treatment to manage side effects were facilitators of adherence. Key practical barriers included difficulties with swallowing tablets, dealing with the burden of treatment and drug cost. Using medication storage devices, following routines and getting help with medications from caregivers were important facilitators of adherence.

Conclusions

An online stroke forum is a novel and valuable resource to investigate use of secondary prevention medications. Analysis of this forum highlighted significant barriers and facilitators of medication adherence faced by stroke survivors and their caregivers. Addressing perceptual and practical barriers highlighted here can inform the development of future interventions aimed at improving adherence to secondary prevention medication after stroke.
A new species of troodontid theropod (Dinosauria: Maniraptora) from the Horseshoe Canyon Formation (Maastrichtian) of Alberta, Canada
Authors: Evans David C. , Cullen Thomas M. , Larson Derek W. , Rego Adam
Published: July 2017

Troodontid material from the Maastrichtian of North America is extremely rare, beyond isolated teeth from microvertebrate sites. Here we describe troodontid frontals from the early Maastrichtian Horseshoe Canyon Formation (Horsethief Member). The most complete specimen, TMP 1993.105.0001, is notably foreshortened and robust when compared with numerous specimens referred to Troodon from the Dinosaur Park Formation, and exhibits several characteristics that distinguish it from other Late Cretaceous troodontids. Morphometric analyses reinforce shape differences between TMP 1993.105.0001 and other North American troodontids, and show that proportional differences are independent of size. We therefore erect a new taxon, Albertavenator curriei gen. et sp. nov., which is diagnosed by the following autapomorphies: (1) primary supraciliary foramen is truncated anteriorly by the lacrimal contact; (2) superficial (ectocranial) surface of the frontal proportionally shorter than all known troodontids, with a length to width ratio under 1.3; and (3) frontoparietal contact in which an enlarged lappet of the frontal extends medially to extensively overlap the lateral region of the anteromedial process of the parietal. Interestingly, tooth and jaw morphology from the single relatively complete dentary recovered from the Horseshoe Canyon cannot be distinguished from dentaries and teeth from the Dinosaur Park Formation. If the dentary and teeth from the Horsethief Member of the Horseshoe Canyon Formation prove to belong to A. curriei, extensive overlap in tooth morphology between the Dinosaur Park and Horseshoe Canyon formations reinforces the notion that tooth morphotypes do not exhibit strong correspondence to species alpha diversity, and may encompass multiple closely related taxa.