bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study into the Role of Nickel Vapor on Surface Modification of a Third-Generation Single-Crystal Superalloy
Authors: Spathara Dimitra , Putman Duncan , Warnken Nils 
Published: June 2018

Abstract
A third-generation single-crystal (SX) superalloy was heat treated at 1350 °C for 24 hours while being exposed to nickel vapor. It is observed that a layer of 60-µm thickness deposited onto the alloy. This prevented the formation of TCP phases and the occurrence of melting, which were reported in previous studies. The interdiffusion between the alloy and deposited layer shows strong indications of cross-diffusion effects, as shown from the composition profile measurements and simulations.
On Shear Testing of Single Crystal Ni-Base Superalloys
Authors: Eggeler G. , Wieczorek N. , Fox F. , Berglund S. , Bürger D. , Dlouhy A. , Wollgramm P. , Neuking K. , Schreuer J. , Agudo Jácome L. , Gao S. , Hartmaier A. , Laplanche G. 
Published: June 2018

Abstract
Shear testing can contribute to a better understanding of the plastic deformation of Ni-base superalloy single crystals. In the present study, shear testing is discussed with special emphasis placed on its strengths and weaknesses. Key mechanical and microstructural results which were obtained for the high-temperature (T ≈ 1000 °C) and low-stress (τ ≈ 200 MPa) creep regime are briefly reviewed. New 3D stereo STEM images of dislocation substructures which form during shear creep deformation in this regime are presented. It is then shown which new aspects need to be considered when performing double shear creep testing at lower temperatures (T < 800 °C) and higher stresses (τ > 600 MPa). In this creep regime, the macroscopic crystallographic [11−2](111) shear system deforms significantly faster than the [01−1](111) system. This represents direct mechanical evidence for a new planar fault nucleation scenario, which was recently suggested (Wu et al. in Acta Mater 144:642–655, 2018). The double shear creep specimen geometry inspired a micro-mechanical in-situ shear test specimen. Moreover, the in-situ SEM shear specimen can be FIB micro-machined from prior dendritic and interdendritic regions. Dendritic regions, which have a lower γ′ volume fraction, show a lower critical resolved shear stress.
Organized Violence and Institutional Child Delivery: Micro-Level Evidence From Sub-Saharan Africa, 1989–2014
Authors: Østby Gudrun , Urdal Henrik , Tollefsen Andreas Forø , Kotsadam Andreas , Belbo Ragnhild , Ormhaug Christin 
Published: June 2018

Abstract
The conditions under which a mother gives birth greatly affect the health risk of both the mother and the child. This article addresses how local exposure to organized violence affects whether women give birth in a health facility. We combine geocoded data on violent events from the Uppsala Conflict Data Program with georeferenced survey data on the use of maternal health care services from the Demographic and Health Surveys. Our sample covers 569,201 births by 390,574 mothers in 31 countries in sub-Saharan Africa. We use a mother fixed-effects analysis to estimate the effect of recent organized violence events within a radius of 50 km of the home of each mother on the likelihood that her child is born in a health facility. The results indicate that geographical and temporal proximity to organized violence significantly reduces the likelihood of institutional births. Although the level of maternal health care overall is lower in rural areas, the negative effect of violence appears to be stronger in urban areas. The study further underscores the importance of household and individual resilience, indicating that the effect of organized violence on institutional child delivery is greater among poor and less-educated mothers.
Neuroimaging and neuropsychological assessment of freezing of gait in Parkinson's disease
Authors: Bluett Brent , Banks Sarah , Cordes Dietmar , Bayram Ece , Mishra Virendra , Cummings Jeffrey , Litvan Irene 
Published: June 2018

AbstractIntroductionFreezing of gait (FOG) is a disabling phenomenon characterized by a brief, episodic absence or reduction of forward progression of the feet despite the intention to walk. It is a common cause of falls and mortality in cases with Parkinson's disease (PD). This article reviews neuropsychological and neuroimaging studies to date and introduces a new study of multimodal imaging and cognition in PD‐FOG.MethodsA comprehensive literature search identified studies using neuropsychological evaluation and/or neuroimaging to evaluate PD‐FOG.ResultsSeveral studies have evaluated PD‐FOG, but few have combined neuropsychological and comprehensive neuroimaging and none longitudinally.DiscussionA study using a combined approach longitudinally evaluating cognitive dysfunction and underlying neural networks in FOG is needed. We introduce the framework of a study which demonstrates the use of establishing an infrastructure for studying neurodegenerative disorders using the National Institutes of Health/National Institute of General Medical Science Center of Biomedical Research Excellence grant mechanism.
Static Rope Evacuation by Helicopter Emergency Medical Services in Rescue Operations in Southeast Norway
Authors: Samdal Martin , Haugland Helge H. , Fjeldet Cato , Rehn Marius , Sandberg Mårten 
Published: June 2018

Introduction Physician-staffed helicopter emergency medical services (HEMS) in Norway are an adjunct to existing search and rescue services. Our aims were to study the epidemiological, operational, and medical aspects of HEMS daylight static rope operations performed in the southeastern part of the country and to examine several quality dimensions that are characteristic of this service. Methods We reviewed the static rope operations performed at 3 HEMS bases during a 3-y period and applied a set of quality indicators designed for physician-staffed emergency medical services to evaluate the quality of care. Data are presented as medians with quartiles, except National Advisory Committee for Aeronautics (NACA) scores, which are presented as mean (SD). Results Fifty-nine static rope operations were identified, involving 60 patients. Median (quartiles) age was 43 (27–55) y. Median (quartiles) take-off time was 9 (5–13) min. Trauma-related injuries were found in 48 patients. The main conditions were lower limb injuries, found in 32 patients. Ten patients experienced medical conditions. Mean (SD) NACA score was 3.3 (1.3). A potential or actual life-threatening diagnosis (NACA score: 4–6) was reported among 15 patients. The main interventions were intravenous lines (19 patients), analgesics (17), and oxygen treatment (14). Four patients were intubated, and 1 thoracostomy was performed. Conclusions Static rope operations are rarely performed. The quality indicators suggest that the service is safe, available, and equitable. Its main benefit seems to be evacuation and the maintenance of readiness before rapid transport of the physician to the scene or the patient to the hospital.
Design and validation of an anatomically based assessment scale for handwashing with alcohol-based hand rub
Authors: Ghazali Daniel Aiham , Thomas Julie , Deilhes Elsa , Laland Catherine , Thévenot Sarah , Richer Jean Pierre , Oriot Denis 
Published: June 2018

AbstractAn anatomically based assessment scale of handwashing quality with alcohol-based hand rub was designed. Contents of the scale divided each hand into 40 zones. Psychometric measurements were studied in 30 participants (120 hand sides). The scale was both valid (Cronbach α: 0·83 dorsal side and 0·73 palmar side) and reproducible (linear regression R2, 0·91; intraclass correlation coefficient, 0·99).
Whole sorghum inclusion and feed form on performance and nutrient digestibility of broiler chickens
Authors: Mabelebele M. , Gous R. M. , O'Neil H. V. Masey , Iji P. A. 
Published: June 2018

SummaryA total of 432, one-day-old broiler chickens were randomly assigned as a 2 × 4 factorial design (pellet or mash and 0, 25, 50, and 75% whole sorghum levels) in a completely randomised experiment, having six replicates with nine birds per replicate. Body weight and feed intake were measured on a pen basis at 10, 25, and 35 days of age and feed conversion ratio calculated. Pelleting diets significantly improved (P<0.05) feed intake, body weight and carcass yield of broiler chickens at 10 and 24 days of age. Heavier relative gizzard weights with lower pH (P<0.05) were recorded for broiler chickens offered mash diets at 35 days old. Feed conversion ratio at 35 days of age increased (P<0.035, quadratic effect) with higher levels of whole sorghum and levelled off at 75% inclusion rates. Relative gizzard weight at 35 days was marginally increased (P<0.033, linear effect) in line with rising sorghum levels. Similarly, relative bursa and liver weights at 35 days increased (P<0.037, quadratic effect and P<0.033, linear effect, respectively) with sorghum inclusion. The results showed that pelleted diets gave superior performance compared to mash diets. Although higher levels of sorghum inclusion in mash diets enhanced gizzard development, performance parameters of birds at 35 days of age were poorer, with 125 g less body weight and an increase in FCR from 1.51 to 1.62 for the 0% and 75% sorghum levels respectively.
Unsteady sheet fragmentation: droplet sizes and speeds
Authors: Wang Y. , Bourouiba L. 
Published: June 2018

Understanding what shapes the drop size distributions produced from fluid fragmentation is important for a range of industrial, natural and health processes. Gilet & Bourouiba (J. R. Soc. Interface, vol. 12, 2015, 20141092) showed that both the size and speed of fragmented droplets are critical to transmission of pathogens in the agricultural context. In this paper, we study both the size and speed distributions of droplets ejected during a canonical unsteady sheet fragmentation from drop impact on a target of comparable size to that of the drop. Upon impact, the drop transforms into a sheet which expands in the air bounded by a rim on which ligaments grow, continuously shedding droplets. We developed high-precision tracking algorithms that capture all ejected droplets, measuring their size and speed, as well as the detachment time from, and link to, their ligament of origin. Both size and speed distributions of all ejected droplets are skewed. We show that the polydispersity and skewness of the distributions are inherently due to the unsteadiness of the sheet expansion. We show that each ligament sheds a single drop at a time throughout the entire sheet expansion by a mechanism of end-pinching. The droplet-to-ligament size ratio $R\approx 1.5$ remains constant throughout the unsteady fragmentation, and is robust to change in impact Weber number. We also show that the population mean speed of the fragmented droplets at a given time is equal to the population mean speed of ligaments one necking time prior to detachment time.
Weakly sheared turbulent flows generated by multiscale inhomogeneous grids
Authors: Zheng Shaokai , Bruce P. J. K. , Graham J. M. R. , Vassilicos J. C. 
Published: June 2018

A group of three multiscale inhomogeneous grids have been tested to generate different types of turbulent shear flows with different mean shear rate and turbulence intensity profiles. Cross hot-wire measurements were taken in a wind tunnel with Reynolds number$Re_{D}$of 6000–20 000, based on the width of the vertical bars of the grid and the incoming flow velocity. The effect of local drag coefficient$C_{D}$on the mean velocity profile is discussed first, and then by modifying the vertical bars to obtain a uniform aspect ratio the mean velocity profile is shown to be predictable using the local blockage ratio profile. It is also shown that, at a streamwise location$x=x_{m}$, the turbulence intensity profile along the vertical direction$u^{\prime }(y)$scales with the wake interaction length$x_{\ast ,n}^{peak}=0.21g_{n}^{2}/(\unicode[STIX]{x1D6FC}C_{D}w_{n})$($\unicode[STIX]{x1D6FC}$is a constant characterizing the incoming flow condition, and$g_{n}$,$w_{n}$are the gap and width of the vertical bars, respectively, at layer$n$) such that$(u^{\prime }/U_{n})^{2}\unicode[STIX]{x1D6FD}^{2}(C_{D}w_{n}/x_{\ast ,n}^{peak})^{-1}\sim (x_{m}/x_{\ast ,n}^{peak})^{b}$, where$\unicode[STIX]{x1D6FD}$is a constant determined by the free-stream turbulence level,$U_{n}$is the local mean velocity and$b$is a dimensionless power law constant. A general framework of grid design method based on these scalings is proposed and discussed. From the evolution of the shear stress coefficient$\unicode[STIX]{x1D70C}(x)$, integral length scale$L(x)$and the dissipation coefficient$C_{\unicode[STIX]{x1D716}}(x)$, a simple turbulent kinetic energy model is proposed that describes the evolution of our grid generated turbulence field using one centreline measurement and one vertical profile of$u^{\prime }(y)$at the beginning of the evolution. The results calculated from our model agree well with our measurements in the streamwise extent up to$x/H\approx 2.5$, where$H$is the height of the grid, suggesting that it might be possible to design some shear flows with desired mean velocity and turbulence intensity profiles by designing the geometry of a passive grid.
On shoaling of solitary waves
Authors: Knowles Jeffrey , Yeh Harry 
Published: June 2018

One of the classic analytical predictions of shoaling-wave amplification is Green’s law – the wave amplitude grows proportional to $h^{-1/4}$, where $h$ is the local water depth. Green’s law is valid for linear shallow-water waves unidirectionally propagating in a gradually varying water depth. On the other hand, conservation of mechanical energy shows that the shoaling-wave amplitude of a solitary wave grows like $a\propto h^{-1}$, if the waveform maintains its solitary-wave identity. Nonetheless, some recent laboratory and field measurements indicate that growth of long waves during shoaling is slower than what is predicted by Green’s law. Obvious missing factors in Green’s law are the nonlinearity and frequency-dispersion effects as well as wave reflection from the beach, whereas the adiabatic shoaling process does not recognize the transformation of the waveform on a beach of finite slope and length. Here we first examine this problem analytically based on the variable-coefficient perturbed Korteweg–de Vries equation. Three analytical solutions for different limits are obtained: (1) Green’s law for the linear and non-dispersive limit, (2) the slower amplitude growth rate for the linear and dispersive limit, as well as (3) nonlinear and non-dispersive limit. Then, in order to characterize the shoaling behaviours for a variety of incident wave and beach conditions, we implement a fifth-order pseudo-spectral numerical model for the full water-wave Euler theory. We found that Green’s law is not the norm but is limited to small incident-wave amplitudes when the wavelength is still small in comparison to the beach length scale. In general, the wave amplification rate during shoaling does not follow a power law. When the incident wave is finite, the shoaling amplification becomes faster than that of Green’s law when the ratio of the wavelength to the beach length is small, but becomes slower when the length ratio increases. We also found that the incident wave starts to amplify prior to its crest arriving at the beach toe due to the wave reflection. Other prominent characteristics and behaviours of solitary-wave shoaling are discussed.
Nodal Solutions for Nonlinear Non-Homogeneous Robin Problems with an Indefinite Potential
Authors: Gasiński Leszek , Papageorgiou Nikolaos S. 
Published: June 2018

AbstractWe consider a nonlinear Robin problem driven by a non-homogeneous differential operator plus an indefinite potential term. The reaction function is Carathéodory with arbitrary growth near±∞. We assume that it is odd and exhibits a concave term near zero. Using a variant of the symmetric mountain pass theorem, we establish the existence of a sequence of distinct nodal solutions which converge to zero.
Provision of physiotherapy rehabilitation following neck dissection in the UK
Authors: Robinson M , Ward L , Mehanna H , Paleri V , Winter S C 
Published: June 2018

AbstractBackgroundNeck dissection is associated with post-operative shoulder dysfunction in a substantial number of patients, affecting quality of life and return to work. There is no current UK national practice regarding physiotherapy after neck dissection.MethodNine regional centres were surveyed to determine their standard physiotherapy practice pre- and post-neck dissection, and to determine pre-emptive physiotherapy for any patients.ResultsEighty-nine per cent of centres never arranged any pre-emptive physiotherapy for any patients. Thirty-three per cent of centres offered routine in-patient physiotherapy after surgery. No centres offered out-patient physiotherapy for all patients regardless of symptoms. Seventy-eight per cent offered physiotherapy for patients with any symptoms, with 11 per cent offering physiotherapy for those with severe dysfunction only. Eleven per cent of centres never offered physiotherapy for any dysfunction.ConclusionThe provision of physiotherapy is most commonly reactive rather than proactive, and usually driven by patient request. There is little evidence of pre-arranged physiotherapy for patients to treat or prevent shoulder dysfunction in the UK.
Learning to trust: social feedback normalizes trust behavior in first-episode psychosis and clinical high risk
Authors: Lemmers-Jansen Imke L. J. , Fett Anne-Kathrin J. , Hanssen Esther , Veltman Dick J. , Krabbendam Lydia 
Published: June 2018

AbstractBackgroundPsychosis is characterized by problems in social functioning that exist well before illness onset, and in individuals at clinical high risk (CHR) for psychosis. Trust is an essential element for social interactions that is impaired in psychosis. In the trust game, chronic patients showed reduced baseline trust, impaired response to positive social feedback, and attenuated brain activation in reward and mentalizing areas. We investigated whether first-episode psychosis patients (FEP) and CHR show similar abnormalities in the neural and behavioral mechanisms underlying trust.MethodsTwenty-two FEP, 17 CHR, and 43 healthy controls performed two trust games, with a cooperative and an unfair partner in the fMRI scanner. Region of interest analyses were performed on mentalizing and reward processing areas, during the investment and outcome phases of the games.ResultsCompared with healthy controls, FEP and CHR showed reduced baseline trust, but like controls, learned to trust in response to cooperative and unfair feedback. Symptom severity was not associated with baseline trust, however in FEP associated with reduced response to feedback. The only group differences in brain activation were that CHR recruited the temporo-parietal junction (TPJ) more than FEP and controls during investment in the unfair condition. This hyper-activation in CHR was associated with greater symptom severity.ConclusionsReduced baseline trust may be associated with risk for psychotic illness, or generally with poor mental health. Feedback learning is still intact in CHR and FEP, as opposed to chronic patients. CHR however show distinct neural activation patterns of hyper-activation of the TPJ.
Posttraumatic psychopathology and the pace of the epigenetic clock: a longitudinal investigation
Authors: Wolf Erika J. , Logue Mark W. , Morrison Filomene G. , Wilcox Elizabeth S. , Stone Annjanette , Schichman Steven A. , McGlinchey Regina E. , Milberg William P. , Miller Mark W. 
Published: June 2018

AbstractBackgroundPosttraumatic stress disorder (PTSD) and stress/trauma exposure are cross-sectionally associated with advanced DNA methylation age relative to chronological age. However, longitudinal inquiry and examination of associations between advanced DNA methylation age and a broader range of psychiatric disorders is lacking. The aim of this study was to examine if PTSD, depression, generalized anxiety, and alcohol-use disorders predicted acceleration of DNA methylation age over time (i.e. an increasing pace, or rate of advancement, of the epigenetic clock).MethodsGenome-wide DNA methylation and a comprehensive set of psychiatric symptoms and diagnoses were assessed in 179 Iraq/Afghanistan war veterans who completed two assessments over the course of approximately 2 years. Two DNA methylation age indices (Horvath and Hannum), each a weighted index of an array of genome-wide DNA methylation probes, were quantified. The pace of the epigenetic clock was operationalized as change in DNA methylation age as a function of time between assessments.ResultsAnalyses revealed that alcohol-use disorders (p= 0.001) and PTSD avoidance and numbing symptoms (p= 0.02) at Time 1 were associated with an increasing pace of the epigenetic clock over time, per the Horvath (but not the Hannum) index of cellular aging.ConclusionsThis is the first study to suggest that posttraumatic psychopathology is longitudinally associated with a quickened pace of the epigenetic clock. Results raise the possibility that accelerated cellular aging is a common biological consequence of stress-related psychopathology, which carries implications for identifying mechanisms of stress-related cellular aging and developing interventions to slow its pace.
A 6-year longitudinal study of predictors for suicide attempts in major depressive disorder
Authors: Eikelenboom Merijn , Beekman Aartjan T. F. , Penninx Brenda W. J. H. , Smit Johannes H. 
Published: June 2018

AbstractBackgroundMajor depressive disorder (MDD), represent a major source of risk for suicidality. However, knowledge about risk factors for future suicide attempts (SAs) within MDD is limited. The present longitudinal study examined a wide range of putative non-clinical risk factors (demographic, social, lifestyle, personality) and clinical risk factors (depressive and suicidal indicators) for future SAs among persons with MDD. Furthermore, we examined the relationship between a number of significant predictors and the incidence of a future SA.MethodsData are from 1713 persons (18–65 years) with a lifetime MDD at the baseline measurement of the Netherlands Study of Depression and Anxiety who were subsequently followed up 2, 4 and 6 years. SAs were assessed in the face-to-face measurements. Cox proportional hazard regression analyses were used to examine a wide range of possible non-clinical and clinical predictors for subsequent SAs during 6-year follow-up.ResultsOver a period of 6 years, 3.4% of the respondents attempted suicide. Younger age, lower education, unemployment, insomnia, antidepressant use, a previous SA and current suicidal thoughts independently predicted a future SA. The number of significant risk factors (ranging from 0 to 7) linearly predicted the incidence of future SAs: in those with 0 predictors the SA incidence was 0%, which increased to 32% incidence in those with 6+ predictors.ConclusionOf the non-clinical factors, particularly socio-economic factors predicted a SA independently. Furthermore, preexisting suicidal ideation and insomnia appear to be important clinical risk factors for subsequent SA that are open to preventative intervention.