bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bipedal Model and Hybrid Zero Dynamics of Human Walking With Foot Slip
Authors: Trkov Mitja , Chen Kuo , Yi Jingang 
Published: April 2019

Abstract
Foot slip is one of the major causes of falls in human locomotion. Analytical bipedal models provide an insight into the complex slip dynamics and reactive control strategies for slip-induced fall prevention. Most of the existing bipedal dynamics models are built on no foot slip assumption and cannot be used directly for such analysis. We relax the no-slip assumption and present a new bipedal model to capture and predict human walking locomotion under slip. We first validate the proposed slip walking dynamic model by tuning and optimizing the model parameters to match the experimental results. The results demonstrate that the model successfully predicts both the human walking and recovery gaits with slip. Then, we extend the hybrid zero dynamics (HZD) model and properties to capture human walking with slip. We present the closed-form of the HZD for human walking and discuss the transition between the nonslip and slip states through slip recovery control design. The analysis and design are illustrated through human walking experiments. The models and analysis can be further used to design and control wearable robotic assistive devices to prevent slip-and-fall.
Stochastic Finite Element Method Elasto-Plastic Analysis of the
Necking Bar With Material Microdefects
Authors: Strąkowski Michał , Kamiński Marcin 
Published: April 2019

Abstract
The main aim of this work is to study a significance of structural microdefects and their uncertainty in structural steel on its elastoplastic large deformations subjected to tensile test with the use of the generalized stochastic perturbation method. Elastoplastic behavior of the macroscopically homogeneous material is defined by the Gurson–Tvergaard–Needleman (GTN) constitutive model, where Young's modulus and this model constants q1 and q2 are consecutively randomized according to the Gauss probability distribution. The stochastic finite element method (SFEM) analysis has been carried out in the system abaqus for the problem of necking under tension to compute the first four probabilistic moments and coefficients of displacements, deformations, and stresses. The tenth-order perturbation scheme has been implemented via statistically optimized least-squares method (LSM) determination of the structural nodal polynomial response functions. A comparison with Monte Carlo simulation (MCS) as well as the semi-analytical integral technique based on the same polynomial bases confirms applicability of the method proposed for the input uncertainty not larger than 0.10. Further numerical experiments with this constitutive law including stochastic nucleation and/or coalescence would be necessary to better understand deformations and stresses of stochastic porous plastic materials. This model may find its applications in various stress states of the plastic materials with voids as well as in numerical simulations of the composite materials with imperfect interphases, for instance, where some parameters exhibit initial Gaussian statistical scattering.
Measurement and improvement of emergency department performance through inspection and rating: an observational study of emergency departments in acute hospitals in England
Authors: Allen Thomas , Walshe Kieran , Proudlove Nathan , Sutton Matt 
Published: April 2019

IntroductionHospital inspection and the publication of inspection ratings are widely used regulatory interventions that may improve hospital performance by providing feedback, creating incentives to change and promoting choice. However, evidence that these interventions assess performance accurately and lead to improved performance is scarce.MethodsWe calculated six standard indicators of emergency department (ED) performance for 118 hospitals in England whose EDs were inspected by the Care Quality Commission, the national regulator in England, between 2013 and 2016. We linked these to inspection dates and subsequent rating scores. We used multilevel linear regression models to estimate the relationship between prior performance and subsequent rating score and the relationship between rating score and post-inspection performance.ResultsWe found no relationship between performance on any of the six indicators prior to inspection and the subsequent rating score. There was no change in performance on any of the six indicators following inspection for any rating score. In each model, CIs were wide indicating no statistically significant relationships.DiscussionWe found no association between established performance indicators and rating scores. This might be because the inspection and rating process adds little to the external performance management that EDs receive. It could also indicate the limited ability of hospitals to improve ED performance because of extrinsic factors that are beyond their control.
Multicentre, randomised controlled trial of PDSAFE, a physiotherapist-delivered fall prevention programme for people with Parkinson’s
Authors: Chivers Seymour Kim , Pickering Ruth , Rochester Lynn , Roberts Helen C , Ballinger Claire , Hulbert Sophia , Kunkel Dorit , Marian Ioana R , Fitton Carolyn , McIntosh Emma , Goodwin Victoria A , Nieuwboer Alice , Lamb Sarah E , Ashburn Ann 
Published: April 2019

ObjectiveTo estimate the effect of a physiotherapist-delivered fall prevention programme for people with Parkinson’s (PwP).MethodsPeople at risk of falls with confirmed Parkinson’s were recruited to this multicentre, pragmatic, investigator blind, individually randomised controlled trial with prespecified subgroup analyses. 474 PwP (Hoehn and Yahr 1–4) were randomised: 238 allocated to a physiotherapy programme and 236 to control. All participants had routine care; the control group received a DVD about Parkinson’s and single advice session at trial completion. The intervention group (PDSAFE) had an individually tailored, progressive home-based fall avoidance strategy training programme with balance and strengthening exercises. The primary outcome was risk of repeat falling, collected by self-report monthly diaries, 0–6 months after randomisation. Secondary outcomes included Mini-BESTest for balance, chair stand test, falls efficacy, freezing of gait, health-related quality of life (EuroQol EQ-5D), Geriatric Depression Scale, Physical Activity Scale for the Elderly and Parkinson’s Disease Questionnaire, fractures and rate of near falling.ResultsAverage age is 72 years and 266 (56%) were men. By 6 months, 116 (55%) of the control group and 125 (61.5%) of the intervention group reported repeat falls (controlled OR 1.21, 95% CI 0.74 to 1.98, p=0.447). Secondary subgroup analyses suggested a different response to the intervention between moderate and severe disease severity groups. Balance, falls efficacy and chair stand time improved with near falls reduced in the intervention arm.ConclusionPDSAFE did not reduce falling in this pragmatic trial of PwP. Other functional tasks improved and reduced fall rates were apparent among those with moderate disease.Trial registration numberISRCTN48152791.
Optical design and laboratory test of an internal pushbroom hyperspectral microscopy
Authors: Zhang Zhoufeng , Hu Bingliang , Yin Qinye , Yu Tao , Zhang Zhaohui 
Published: April 2019

Hyperspectral imaging is an emerging technology for various medical applications, especially in disease diagnosis of early and biomedical research based on their unique spectral signatures. A hyperspectral microscopy based on a prism-grating-prism is designed for various medical applications. The spectral range between 400 nm to 800 nm is sampled by 256 spectral channels, the modulation transfer function (MTF) values of full spectrum and full field of view are close to the diffraction limit, the smile is less than 6.4% of a pixel, and the keystone is less than 1.6% of a pixel. At the same time, the hyperspectral microscopy used an internal pushbroom technology, which has the advantages of compact structure and good portability. The spectral imaging results demonstrate the great potential of this internal pushbroom hyperspectral microscopy for the pathologists to automatically detect tumor tissue in pathological slides and early disease diagnosis.
Hair cell and neural contributions to the cochlear summating potential
Authors: Pappa Andrew K. , Hutson Kendall A. , Scott William C. , Wilson J. David , Fox Kevin E. , Masood Maheer M. , Giardina Christopher K. , Pulver Stephen H. , Grana Gilberto D. , Askew Charles , Fitzpatrick Douglas C. 
Published: April 2019

The cochlear summating potential (SP) to a tone is a baseline shift that persists for the duration of the burst. It is often considered the most enigmatic of cochlear potentials because its magnitude and polarity vary across frequency and level and its origins are uncertain. In this study, we used pharmacology to isolate sources of the SP originating from the gerbil cochlea. Animals either had the full complement of outer and inner hair cells (OHCs and IHCs) and an intact auditory nerve or had systemic treatment with furosemide and kanamycin (FK) to remove the outer hair cells. Responses to tone bursts were recorded from the round window before and after the neurotoxin kainic acid (KA) was applied. IHC responses were then isolated from the post-KA responses in FK animals, neural responses were isolated from the subtraction of post-KA from pre-KA responses in NH animals, and OHC responses were isolated by subtraction of post-KA responses in FK animals from post-KA responses in normal hearing (NH) animals. All three sources contributed to the SP; OHCs with a negative polarity and IHCs and the auditory nerve with positive polarity. Thus the recorded SP in NH animals is a sum of contributions from different sources, contributing to the variety of magnitudes and polarities seen across frequency and intensity. When this information was applied to observations of the SP recorded from the round window in human cochlear implant subjects, a strong neural contribution to the SP was confirmed in humans as well as gerbils. NEW & NOTEWORTHY Of the various potentials produced by the cochlea, the summating potential (SP) is typically described as the most enigmatic. Using combinations of ototoxins and neurotoxins, we show contributions to the SP from the auditory nerve and from inner and outer hair cells, which differ in polarity and vary in size across frequency and level. This complexity of sources helps to explain the enigmatic nature of the SP.
A supervised machine learning approach to characterize spinal network function
Authors: Dalrymple A. N. , Sharples S. A. , Osachoff N. , Lognon A. P. , Whelan P. J. 
Published: April 2019

Spontaneous activity is a common feature of immature neuronal networks throughout the central nervous system and plays an important role in network development and consolidation. In postnatal rodents, spontaneous activity in the spinal cord exhibits complex, stochastic patterns that have historically proven challenging to characterize. We developed a software tool for quickly and automatically characterizing and classifying episodes of spontaneous activity generated from developing spinal networks. We recorded spontaneous activity from in vitro lumbar ventral roots of 16 neonatal [postnatal day (P)0–P3] mice. Recordings were DC coupled and detrended, and episodes were separated for analysis. Amplitude-, duration-, and frequency-related features were extracted from each episode and organized into five classes. Paired classes and features were used to train and test supervised machine learning algorithms. Multilayer perceptrons were used to classify episodes as rhythmic or multiburst. We increased network excitability with potassium chloride and tested the utility of the tool to detect changes in features and episode class. We also demonstrate usability by having a novel experimenter use the program to classify episodes collected at a later time point (P5). Supervised machine learning-based classification of episodes accounted for changes that traditional approaches cannot detect. Our tool, named SpontaneousClassification, advances the detail in which we can study not only developing spinal networks, but also spontaneous networks in other areas of the nervous system.NEW & NOTEWORTHY Spontaneous activity is important for nervous system network development and consolidation. Our software uses machine learning to automatically and quickly characterize and classify episodes of spontaneous activity in the spinal cord of newborn mice. It detected changes in network activity following KCl-enhanced excitation. Using our software to classify spontaneous activity throughout development, in pathological models, or with neuromodulation, may offer insight into the development and organization of spinal circuits.
Rostral lumbar segments are the key controllers of hindlimb locomotor rhythmicity in the adult spinal rat
Authors: Gerasimenko Yury , Preston Chet , Zhong Hui , Roy Roland R. , Edgerton V. Reggie , Shah Prithvi K. 
Published: April 2019

The precise location and functional organization of the spinal neuronal locomotor-related networks in adult mammals remain unclear. Our recent neurophysiological findings provided empirical evidence that the rostral lumbar spinal cord segments play a critical role in the initiation and generation of the rhythmic activation patterns necessary for hindlimb locomotion in adult spinal rats. Since added epidural stimulation at the S1 segments significantly enhanced the motor output generated by L2 stimulation, these data also suggested that the sacral spinal cord provides a strong facilitory influence in rhythm initiation and generation. However, whether L2 will initiate hindlimb locomotion in the absence of S1 segments, and whether S1 segments can facilitate locomotion in the absence of L2 segments remain unknown. Herein, adult rats received complete spinal cord transections at T8 and then at either L2 or S1. Rats with spinal cord transections at T8 and S1 remained capable of generating coordinated hindlimb locomotion when receiving epidural stimulation at L2 and when ensembles of locomotor related loadbearing input were present. In contrast, minimal locomotion was observed when S1 stimulation was delivered after spinal cord transections at T8 and L2. Results were similar when the nonspecific serotonergic agonists were administered. These results demonstrate in adult rats that rostral lumbar segments are essential for the regulation of hindlimb locomotor rhythmicity. In addition, the more caudal spinal networks alone cannot control locomotion in the absence of the rostral segments around L2 even when loadbearing rhythmic proprioceptive afferent input is imposed. NEW & NOTEWORTHY The exact location of the spinal neuronal locomotor-related networks in adult mammals remains unknown. The present data demonstrate that when the rostral lumbar spinal segments (~L2) are completely eliminated in thoracic spinal adult rats, hindlimb stepping is not possible with neurochemical modulation of the lumbosacral cord. In contrast, eliminating the sacral cord retains stepping ability. These observations highlight the importance of rostral lumbar segments in generating effective mammalian locomotion.
Atypical Chemokine Receptor 1 (DARC/ACKR1) in Breast Tumors Is Associated with Survival, Circulating Chemokines, Tumor-Infiltrating Immune Cells, and African Ancestry
Authors: Jenkins Brittany D. , Martini Rachel N. , Hire Rupali , Brown Andrea , Bennett Briana , Brown I'nasia , Howerth Elizabeth W. , Egan Mary , Hodgson Jamie , Yates Clayton , Kittles Rick , Chitale Dhananjay , Ali Haythem , Nathanson David , Nikolinakos Petros , Newman Lisa , Monteil Michele , Davis Melissa B. 
Published: April 2019

Abstract

Background:
Tumor-specific immune response is an important aspect of disease prognosis and ultimately impacts treatment decisions for innovative immunotherapies. The atypical chemokine receptor 1 (ACKR1 or DARC) gene plays a pivotal role in immune regulation and harbors several single-nucleotide variants (SNV) that are specific to sub-Saharan African ancestry.

Methods:
Using computational The Cancer Genome Atlas (TCGA) analysis, case–control clinical cohort Luminex assays, and CIBERSORT deconvolution, we identified distinct immune cell profile–associated DARC/ACKR1 tumor expression and race with increased macrophage subtypes and regulatory T cells in DARC/ACKR1-high tumors.

Results:
In this study, we report the clinical relevance of DARC/ACKR1 tumor expression in breast cancer, in the context of a tumor immune response that may be associated with sub-Saharan African ancestry. Briefly, we found that for infiltrating carcinomas, African Americans have a higher proportion of DARC/ACKR1-negative tumors compared with white Americans, and DARC/ACKR1 tumor expression is correlated with proinflammatory chemokines, CCL2/MCP-1 (P &lt;0.0001) and anticorrelated with CXCL8/IL8 (P &lt;0.0001). Sub-Saharan African-specific DARC/ACKR1 alleles likely drive these correlations. Relapse-free survival (RFS) and overall survival (OS) were significantly longer in individuals with DARC/ACKR1-high tumors (P &lt;1.0 × 10−16 and P &lt;2.2 × 10−6, respectively) across all molecular tumor subtypes.

Conclusions:
DARC/AKCR1 regulates immune responses in tumors, and its expression is associated with sub-Saharan African-specific alleles. DARC/ACKR1-positive tumors will have a distinct immune response compared with DARC/AKCR1-negative tumors.

Impact:
This study has high relevance in cancer management, as we introduce a functional regulator of inflammatory chemokines that can determine an infiltrating tumor immune cell landscape that is distinct among patients of African ancestry.
A Prototype Quantitative Precipitation Estimation Algorithm for Operational S-Band Polarimetric Radar Utilizing Specific Attenuation and Specific Differential Phase. Part I: Algorithm Description
Authors: Wang Yadong , Cocks Stephen , Tang Lin , Ryzhkov Alexander , Zhang Pengfei , Zhang Jian , Howard Kenneth 
Published: April 2019

Abstract
A prototype quantitative precipitation estimate (QPE) algorithm that utilizes specific attenuation A and specific differential phase KDP was developed for inclusion into the Multi-Radar Multi-Sensor (MRMS) system and the Weather Surveillance Radar-1988 Doppler (WSR-88D) network. Special attention is given to the optimization of the factor α used for computation of a path-integrated attenuation from a total span of differential phase along the propagation path in rain. It is suggested to estimate α from a slope of the ZDR dependence on Z in rain. The use of real-time adjusted α allows us to capture the variations of the drop size distributions, and therefore improve the QPE accuracy. It is demonstrated that the factor α is generally higher for tropical rain type compared to continental rain. Since the R(A) approach is only valid for pure rainfall, the R(KDP) relation is suggested as a complement in areas of hail contamination. The paper contains a description of the basic version of the R(A) and R(KDP) algorithm and recommendations for its further optimization.
The Ivy League–Big Ten Epidemiology of Concussion Study: A Report on Methods and First Findings
Authors: Putukian Margot , D’Alonzo Bernadette A. , Campbell-McGovern Carolyn S. , Wiebe Douglas J. 
Published: April 2019

Background: Little is known about the nature of concussion injury among university student-athletes, including concussion incidence and rates across sports, the mechanisms of injury, the type of activity during competition or practice, and the time to return to academics, return to sport, and symptom resolution. Purpose: To describe methods of the Ivy League–Big Ten Epidemiology of Concussion Study and first epidemiologic findings. Study Design: Descriptive epidemiology study. Methods: A prospective cohort study was conducted with data accrued through a surveillance system that was launched in the 2013-2014 athletic season. Surveillance continues to operate by detecting and collecting sport-related concussion (SRC) cases and non-SRC cases in addition to outcomes among university student-athletes. Results: A total of 1922 cases of SRC (649 women, 1004 men) among athletes from 27 sports, including varsity sports and club rugby, were enrolled during the 5 athletic seasons from 2013-2014 through 2017-2018. American football had the most cases (n = 495, 25.8%), followed by women’s rugby (n = 199, 6.2%), men’s ice hockey (n = 106, 5.5%), men's lacrosse (n = 105, 5.5%), women's soccer (n = 103, 5.4%), wrestling (n = 93, 4.8%), and men's soccer (n = 89, 4.6%), and women's ice hockey (n = 78, 4.1%). The highest overall concussion rates occurred in women’s lacrosse (1.35 concussions per 1000 athletic exposures [AEs]) and football (1.26 per 1000 AEs). Rates of concussion were generally higher during competition than practice and were highest during wrestling competition (4.06 per 1000 AEs) and second highest during football competition (3.68 per 1000 AEs). The median number of concussion symptoms was 7. Time to symptom resolution was longer for athletes with ≥7 symptoms versus <7 ( P < .001) but did not differ across the 4 sports with rules comparable by sex and did not differ significantly between women and men (median, 8 vs 9 days, respectively). Women and men did not differ in days to return to academics, exertion activities, or competition. Conclusion: This multisite collaborative endeavor has produced a robust database yielding novel opportunities to better understand the epidemiology of concussion among university student-athletes participating in a variety of sports. Given the setting and number of cases, these findings add to our understanding of SRC and are the first of many that will be generated over the coming years from this large study that continues in its sixth year.
The effect of high-dose cytarabine followed by autologous hematopoietic stem cell transplantation on the outcome of patients with mantle cell lymphoma
Authors: Çakar Merih K , Tekgündüz Emre , Dal Mehmet S , Merdin Alparslan , Başçı Semih , İskender Dicle , Uğur Bilge , Bekdemir Filiz , Yıldız Jale , Ulu Bahar U , Bakırtaş Mehmet , Yiğenoğlu Tuğçe N , Batgi Hikmetullah , Kaya Ali H , İskender Dicle , Altuntaş Fevzi 
Published: April 2019

Introduction The aim of this study was to investigate the influence of high-dose cytosine arabinoside (HDAC)-containing treatments followed by autologous hematopoietic stem cell transplantation on the survival of patients with mantle cell lymphoma. Material and methods The data of 27 MCL patients who were followed-up between January 2009 and December 2015 were analyzed retrospectively. Results The median age of the patients was 63 (range, 45–82) with 22 (81.4%) males and 5 (18.6%) females. Eight of 27 patients were treated with HDAC-containing regimens either as induction or salvage chemotherapy followed by autologous hematopoietic stem cell transplantation (AHSCT). The patients who received HDAC-containing regimen followed by AHSCT were found to have better one-year survival compared to others ( p = 0.03). Median follow-up of patient cohort was 27.6 months and median overall survival (OS) was not reached. The probability of one-year OS for all patients was 76.8%. Conclusion Our findings suggest that HDAC treatment followed by AHSCT seems to provide the best outcome for young-fit patients presenting with mantle cell lymphoma.