bluuebunny/crossref_metadata_2025_split huggingface dataset:
Geometric Design, Meshing Simulation, and Stress Analysis of Pure Rolling Rack and Pinion Mechanisms
Authors: Chen Zhen , Zeng Ming , Fuentes-Aznar Alfonso 
Published: September 2019

Abstract
The geometric design, meshing simulation, and stress analysis of pure rolling rack and pinion mechanisms are presented. Both the pinion and the rack are based on the active design of the meshing line to provide pure rolling for the whole cycle of meshing. The parametric equations of the contact curves on the rack and pinion tooth surfaces are determined by coordinate transformation of the meshing line equations. Three types of meshing are derived according to the motion of the generatrices along the calculated contact curves: convex-to-concave meshing, convex-to-plane meshing, and convex-to-convex meshing. Then, the basic design parameters are analyzed and formulas for calculation of the geometric size are given. Four different cases of design are considered to compare the meshing performance and mechanical behavior of the proposed gear mechanisms. The results include contact patterns, the unloaded function of transmission errors, and the evaluation of stresses along two cycles of meshing. The analysis of the results shows that the proposed method of design of pure rolling meshing reduces the relative sliding between tooth surfaces, whereas it decreases the contact strength of the tooth surfaces. However, if the design parameters are properly evaluated as a result of simulation and applied as proposed here, the mechanical behavior of the proposed rack and pinion mechanisms can be more favorable than that of the standard geometry of involute rack and pinion sets.
Nano−porous pyrite and organic matter in 3.5-billion-year-old stromatolites record primordial life
Authors: Baumgartner Raphael J. , Van Kranendonk Martin J. , Wacey David , Fiorentini Marco L. , Saunders Martin , Caruso Stefano , Pages Anais , Homann Martin , Guagliardo Paul 
Published: September 2019

Abstract
Stromatolites of the ∼3.5 billion-year-old Dresser Formation (Pilbara Craton, Western Australia) are considered to be some of Earth’s earliest convincing evidence of life. However, uniquely biogenic interpretations based on surface outcrops are precluded by weathering, which has altered primary mineralogy and inhibited the preservation of microbial remains. Here, we report on exceptionally preserved, strongly sulfidized stromatolites obtained by diamond drilling from below the weathering profile. These stromatolites lie within undeformed hydrothermal-sedimentary strata and show textural features that are indicative of biogenic origins, including upward-broadening and/or upward-branching digitate forms, wavy to wrinkly laminae, and finely laminated columns that show a thickening of laminae over flexure crests. High-resolution textural, mineralogical, and chemical analysis reveals that the stromatolites are dominated by petrographically earliest, nano-porous pyrite that contains thermally mature, N-bearing organic matter (OM). This nano-porous pyrite is consistent with a formation via sulfidization of an originally OM-dominated matrix. Evidence for its relationship with microbial communities are entombed OM strands and filaments, whose microtexture and chemistry are consistent with an origin as mineralized biofilm remains, and carbon isotope data of extracted OM (δ13COM = −29.6‰ ± 0.3‰ VPDB [Vienna Peedee belemnite]), which lie within the range of biological matter. Collectively, our findings provide exceptional evidence for the biogenicity of some of Earth’s oldest stromatolites through preservation of OM, including microbial remains, by sulfidization.
The isolated caecal patch lesion: a clinical, endoscopic and histopathological study
Authors: Ekanayaka Anju , Anderson John T , Lucarotti Michele E , Valori Roland M , Shepherd Neil A 
Published: September 2019

ObjectiveTo describe and investigate the potential causes of the isolated caecal patch lesion, a previously undescribed endoscopic phenomenon of a lesion fulfilling endoscopic and histopathological criteria for chronic inflammatory bowel disease but without evidence of similar inflammatory pathology elsewhere at colonoscopy.MethodsCases were collected prospectively by one specialist gastrointestinal pathologist over a 10-year period. Full endoscopic and histopathological analysis was undertaken and follow-up sought to understand the likely cause(s) of the lesions.ResultsSix cases are described. Two had very close links with ulcerative colitis, one predating the onset of classical distal disease and the other occurring after previous demonstration of classical distal ulcerative colitis. Two occurred in younger patients and we postulate that these lesions may predict the subsequent onset of chronic inflammatory bowel disease. Finally two can be reasonably attributed to the effects of non-steroidal inflammatory agent therapy.ConclusionsCaecal patch lesions can be demonstrated in isolation. Despite the strong association of caecal patch lesions with ulcerative colitis, solitary lesions may well have disparate causes but nevertheless possess a close relationship with chronic inflammatory bowel disease.
Right-wing populism and self-rated health in Europe: a multilevel analysis
Authors: Backhaus Insa , Kino Shiho , La Torre Giuseppe , Kawachi Ichiro 
Published: September 2019

BackgroundIndividuals who identify as politically conservative have been previously shown to report better self-rated health compared with liberals. We tested whether this association still holds for right-wing populists, which are gaining strength as a political force in Europe in recent decades.MethodsWe analysed data from 24 617 respondents nested within 18 European countries included in the 2016 European Social Survey. Multilevel analyses were conducted to assess the association between political ideology and self-rated health, adjusting for other individual covariates (happiness and social capital).ResultsIndividuals who voted for right-wing populist parties were 43% more likely to report fair/poor health compared with traditional conservatives (OR=1.43, 95% CI 1.23 to 1.67). The association was attenuated (OR=1.21, 95% CI 1.03 to 1.42) after controlling for additional individual-level variables, including happiness and access to social capital. Higher levels of social capital (informal networks, OR=0.40, 95% CI 0.29 to 0.56; trust, OR=0.82, 95% CI 0.74 to 0.92) and happiness (OR=0.18, 95% CI 0.15 to 0.22) were protectively correlated with fair/poor self-rated health.ConclusionsIndividuals voting for right-wing populist parties report worse health compared with conservatives. It remains unclear whether ideology is just a marker for health-related practices, or whether the values and beliefs associated with a particular brand of ideology lead to worse health.
Outcomes of the short Synacthen test: what is the role of the 60 min sample in clinical practice?
Authors: Dineen Rosemary , Mohamed Ahmed , Gunness Anjuli , Rakovac Ana , Cullen Emer , Barnwell Niamh , Neary Catherine , Behan Lucy-Ann , Boran Gerard , Gibney James , Sherlock Mark 
Published: September 2019

AbstractIn recent years, the short Synacthen test (SS) has become the most widely used test to assess adrenal reserve. Despite its frequent use, there are still several areas related to the short Synacthen test (SST), which have no consensus including the optimum sampling times, that is, whether a 60 min post-Synacthen administration cortisol is necessary or not.MethodologyWe performed a retrospective data analysis of 492 SSTs performed on adult patients in a tertiary referral teaching hospital in Ireland. The SSTs were performed in the inpatient and outpatient setting and included patients across all medical disciplines and not exclusively to the endocrinology department.Results313 patients had 0, 30 and 60 min samples available for analysis. A total of 270/313 (82%) were deemed to pass the test, that is, cortisol ≥500 nmol/L at both 30 and 60 min. Of the 313 patients, 19 (6%) patients had an indeterminate response, cortisol &lt;500 nmol/L at 30 min, but rising to ≥500 nmol/L on the 60 min sample. Of these 19 patients, only 9/19 patients had a serum cortisol level at 30 min &lt;450 nmol/L, requiring clinical treatment with glucocorticoid replacement. All 24/313 (8%) patients who had insufficient responses at 60 min were also insufficient at 30 min sampling. No individuals passed (≥500 nmol/L) at 30 min and then failed (&lt;500 nmol/L) at 60 min.ConclusionUsing the 30 min cortisol sample post-Synacthen administration alone identifies clinically relevant adrenal insufficiency in the majority of cases. A small subset of patients have a suboptimal response at 30 min but have a 60 min cortisol concentration above the threshold for a pass. Data regarding the long-term outcomes and management of such patients are lacking and require further study.
Prevalence of skin wounds in working donkeys in Bukombe, Tanzania
Authors: Rayner Emma , Airikkala‐Otter Ilona , Susheelan Aswin , Gibson Andrew , Itaba Richard , Mayani Thomas , Mellanby Richard J , Gamble Luke 
Published: September 2019

BackgroundPreventable wounds are a common welfare issue in working donkeys in many countries. In the Bukombe District of Tanzania, there are estimated to be 3000 working donkeys, used primarily to transport loads for direct income generation. For historical reasons, oxen‐yoke carts are used; their design is inappropriate for donkeys and results in serious neck wounds. The project aim was to assess the prevalence and nature of wounds in working donkeys.MethodsIn November 2018, 148 donkeys owned by 48 owners were examined, and data were collected.ResultsThe study revealed that one or more wounds were present in 56.1% of the population and yoke‐related, dorsal neck wounds comprised 79.5% of these. These wounds ranged in surface area from 1 cm2 to 300 cm2. Clinically, 96.6% of all wound types were superficial and the majority of these (51.1%) were granulating.ConclusionThese data will enable the future evaluation of targeted interventions aimed at reducing the prevalence of these specific wounds.
Definable V-topologies, Henselianity and NIP
Authors: Halevi Yatir , Hasson Assaf , Jahnke Franziska 
Published: September 2019

We initiate the study of definable [Formula: see text]-topologies and show that there is at most one such [Formula: see text]-topology on a [Formula: see text]-henselian NIP field. Equivalently, we show that if [Formula: see text] is a bi-valued NIP field with [Formula: see text] henselian (respectively, [Formula: see text]-henselian), then [Formula: see text] and [Formula: see text] are comparable (respectively, dependent). As a consequence, Shelah’s conjecture for NIP fields implies the henselianity conjecture for NIP fields. Furthermore, the latter conjecture is proved for any field admitting a henselian valuation with a dp-minimal residue field. We conclude by showing that Shelah’s conjecture is equivalent to the statement that any NIP field not contained in the algebraic closure of a finite field is [Formula: see text]-henselian.
Role of the cortex in visuomotor control of arm stability
Authors: Snyder Dylan B. , Beardsley Scott A. , Schmit Brian D. 
Published: September 2019

Whereas numerous motor control theories describe the control of arm trajectory during reach, the control of stabilization in a constant arm position (i.e., visuomotor control of arm posture) is less clear. Three potential mechanisms have been proposed for visuomotor control of arm posture: 1) increased impedance of the arm through co-contraction of antagonistic muscles, 2) corrective muscle activity via spinal/supraspinal reflex circuits, and/or 3) intermittent voluntary corrections to errors in position. We examined the cortical mechanisms of visuomotor control of arm posture and tested the hypothesis that cortical error networks contribute to arm stabilization. We collected electroencephalography (EEG) data from 10 young healthy participants across four experimental planar movement tasks. We examined brain activity associated with intermittent voluntary corrections of position error and antagonist co-contraction during stabilization. EEG beta-band (13–26 Hz) power fluctuations were used as indicators of brain activity, and coherence between EEG electrodes was used as a measure of functional connectivity between brain regions. Cortical activity in the sensory, motor, and visual areas during arm stabilization was similar to activity during volitional arm movements and was larger than activity during co-contraction of the arm. However, cortical connectivity between the sensorimotor and visual regions was higher during arm stabilization compared with volitional arm movements and co-contraction of the arm. The difference in cortical activity and connectivity between tasks might be attributed to an underlying visuomotor error network used to update motor commands for visuomotor control of arm posture. NEW & NOTEWORTHY We examined cortical activity and connectivity during control of stabilization in a constant arm position (i.e., visuomotor control of arm posture). Our findings provide evidence for cortical involvement during control of stabilization in a constant arm position. A visuomotor error network appears to be active and may update motor commands for visuomotor control of arm posture.
Soleus single motor units show stronger coherence with Achilles tendon vibration across a broad bandwidth relative to medial gastrocnemius units while standing
Authors: Mildren Robyn L. , Peters Ryan M. , Carpenter Mark G. , Blouin Jean-Sébastien , Inglis J. Timothy 
Published: September 2019

To probe the frequency characteristics of somatosensory responses in the triceps surae muscles, we previously applied suprathreshold noisy vibration to the Achilles tendon and correlated it with ongoing triceps surae muscle activity (recorded via surface EMG) during standing. Stronger responses to tendon stimuli were observed in soleus (Sol) relative to medial gastrocnemius (MGas) surface EMG; however, it is unknown whether differences in motor unit activity or limitations of surface EMG could have influenced this finding. Here, we inserted indwelling EMG into Sol and MGas to record the activity of single motor units while we applied noisy vibration (10–115 Hz) to the right Achilles tendon of standing participants. We analyzed the relationship between vibration acceleration and the spike activity of active single motor units through estimates of coherence, gain, phase, and cross-covariance. We also applied sinusoidal vibration at frequencies from 10 to 100 Hz (in 5-Hz increments) to examine whether motor units demonstrate nonlinear synchronization or phase locking at higher frequencies. Relative to MGas single motor units, Sol units demonstrated stronger coherence and higher gain with noisy vibration across a bandwidth of 7–68 Hz, and larger peak-to-peak cross-covariance at all four stimulus amplitudes examined. Sol and MGas motor unit activity was modulated over the time course of the sinusoidal stimuli across all frequencies, but their phase-locking behavior was minimal. These findings suggest Sol plays a prominent role in responding to disturbances transmitted through the Achilles tendon across a broad frequency band during standing. NEW & NOTEWORTHY We examined the relationship between Achilles tendon stimuli and spike times of single soleus (Sol) and medial gastrocnemius (MGas) motor units during standing. Relative to MGas, Sol units demonstrated stronger coherence and higher gain with noisy stimuli across a bandwidth of 7–68 Hz. Sol and MGas units demonstrated minimal nonlinear phase locking with sinusoidal stimuli. These findings indicate Sol plays a prominent role in responding to tendon stimuli across a broad frequency band.
The Phenotypes of Proliferating Glioblastoma Cells Reside on a Single Axis of Variation
Authors: Wang Lin , Babikir Husam , Müller Sören , Yagnik Garima , Shamardani Karin , Catalan Francisca , Kohanbash Gary , Alvarado Beatriz , Di Lullo Elizabeth , Kriegstein Arnold , Shah Sumedh , Wadhwa Harsh , Chang Susan M. , Phillips Joanna J. , Aghi Manish K. , Diaz Aaron A. 
Published: September 2019

Abstract

Although tumor-propagating cells can be derived from glioblastomas (GBM) of the proneural and mesenchymal subtypes, a glioma stem-like cell (GSC) of the classic subtype has not been identified. It is unclear whether mesenchymal GSCs (mGSC) and/or proneural GSCs (pGSC) alone are sufficient to generate the heterogeneity observed in GBM. We performed single-cell/single-nucleus RNA sequencing of 28 gliomas, and single-cell ATAC sequencing for 8 cases. We found that GBM GSCs reside on a single axis of variation, ranging from proneural to mesenchymal. In silico lineage tracing using both transcriptomics and genetics supports mGSCs as the progenitors of pGSCs. Dual inhibition of pGSC-enriched and mGSC-enriched growth and survival pathways provides a more complete treatment than combinations targeting one GSC phenotype alone. This study sheds light on a long-standing debate regarding lineage relationships among GSCs and presents a paradigm by which personalized combination therapies can be derived from single-cell RNA signatures, to overcome intratumor heterogeneity.

Significance:
Tumor-propagating cells can be derived from mesenchymal and proneural glioblastomas. However, a stem cell of the classic subtype has yet to be demonstrated. We show that classic-subtype gliomas are comprised of proneural and mesenchymal cells. This study sheds light on a long-standing debate regarding lineage relationships between glioma cell types.
See related commentary by Fine, p. 1650.
This article is highlighted in the In This Issue feature, p. 1631
Portraying the Impact of the Tibetan Plateau on Global Climate
Authors: Yang Haijun , Shen Xingchen , Yao Jie , Wen Qin 
Published: September 2019

AbstractAs the most extensive highland in the world, the Tibetan Plateau (TP) plays an important role in shaping the global climate. Quantifying the effect of the TP on global climate is the first step for a full understanding of the TP’s standing on planet Earth. Through coupled model sensitivity experiments, we draw a panorama of the TP’s global impact in this paper. Our model results show that the absence of the TP would result in a 4°C colder and 10% drier climate in the Northern Hemisphere (NH). The TP has a striking remote effect on the North Atlantic. Removing the TP would enhance the westerlies in the mid- to high latitudes of the NH and weaken the easterlies over the tropical Pacific. More moisture would be relocated from the tropical Pacific to the North Atlantic, shutting down the Atlantic thermohaline circulation, which would eventually result in more than 15°C colder and 20% drier climate over the North Atlantic. Our model results suggest that the presence of the TP may have contributed greatly to the hospitable modern climate in the NH, by promoting the establishment of the thermohaline circulation in the Atlantic, and therefore enhancing the northward ocean heat transport and atmosphere moisture transport across the equator.
The role of single pill combination therapy in the prevention of ischaemic stroke
Authors: Ho Wan Y , Abdul-Rahim Azmil H , Dawson Jesse , Cameron Alan C 
Published: September 2019

Background and aims The role of single pill combination therapy for stroke prevention remains to be established. We explored the perspectives of stroke survivors and healthcare professionals on single pill combination therapy for stroke prevention. Methods We conducted focus groups involving stroke survivors and healthcare professionals. Results We recruited six stroke survivors: four (67%) were female and mean age was 70 ± 12 years; and eight healthcare professionals (three Stroke Consultants, two Nurse Specialists, three General Practitioners). Improved adherence is the main perceived benefit of single pill combination therapy, although concerns exist surrounding less individualised care, unsuitability for use in the acute setting, reduced ability to titrate doses and difficulty identifying the cause of side effects. The clinical stability of patients, alongside single pill combination therapy efficacy, cost, side effect profile and evidence base for impact on risk factors and clinical outcomes are key factors influencing acceptability. Stroke survivors and healthcare professionals feel single pill combination therapy is most suitable for stable patients, although there is no evidence base for its use in this context. Conclusion Stroke healthcare professionals and stroke survivors are most amenable to using single pill combination therapy for stable patients, although its role in this context should be evaluated in studies with risk factor targets and clinical outcomes as endpoints.
Systemic lupus erythematosus and pregnancy: the challenge of improving antenatal care and outcomes
Authors: Pastore D E A , Costa M L , Surita F G 
Published: September 2019

Objectives The objective of this article is to describe maternal and perinatal outcomes in women with systemic lupus erythematosus (SLE) followed in a high-risk prenatal outpatient clinic at a referral center. Methods This observational study included pregnant women with SLE who underwent prenatal follow-up and childbirth at the Women’s Hospital, University of Campinas, from January 2012 to January 2018. All women were followed according to the institution’s protocol for pregnant women with SLE. They were subdivided into two groups according to the presence of disease activity during the preconception and gestation periods, and evaluated according to the Systemic Lupus Erythematosus Disease Activity Index and Systemic Lupus Erythematosus Pregnancy Disease Activity Index scales. Data were retrieved from patients’ medical records. Chi-square, Fisher exact and Mann-Whitney tests and multivariable analyses were performed. Statistical significance level was 5% ( p < .05). Results A total of 125 cases were initially included; those who were lost to follow-up or gave birth at another hospital were further excluded, with 102 pregnancies (of 95 women) remaining. The mean age of the women was 27.7 years (SD 5.44), and 48% were in their first gestation. The average duration of disease was 6.79 years (SD 5.38), with 92.1% receiving SLE-specific therapy. SLE flare occurred in 8.9% during the preconception period and 23.5% during gestation. Preterm premature rupture of membranes (16.6%), preeclampsia or eclampsia (15.6%) and preterm labor (12.7%) were the most frequent complications. The mean gestational age at birth was 34.4 weeks (SD 5.9); the preterm birth rate was 46.8%, the low birth weight rate was 35.1%, and intensive neonatal care admission was 40.4%. Four fetal deaths and one maternal death occurred, all of them in the group with SLE flares. Multivariable logistic regression analysis showed that preconception lupus activity had a six-fold increased rate of gestational loss (odds ratio (OR): 6.14 (95% confidence interval (CI) 1.26–29.99)), and lupus activity during pregnancy had a five-fold increased rate of prematurity at less than 34 weeks (OR: 5.02 (95% CI: 1.90–13.30)). Conclusions Despite the low percentages of women with pregestational and pregnancy-active disease, we found high incidences of maternal and perinatal complications. Preconception SLE activity increased gestational loss, and SLE activity during pregnancy increased prematurity. Effective immunosuppressive therapy was able to decrease clinical and laboratory activity of SLE; however, unfavorable perinatal outcomes still occurred, even when lupus activity was under control. Pregnancy in women with SLE is always a challenge.