bluuebunny/crossref_metadata_2025_split huggingface dataset:
The lysophosphatidic acid axis in fibrosis: Implications for glaucoma
Authors: O'Regan Amy , O'Brien Colm J. , Eivers Sarah B. 
Published: May 2021

AbstractGlaucoma is a common progressive optic neuropathy that results in visual field defects and can lead to irreversible blindness. The pathophysiology of glaucoma involves dysregulated extracellular matrix remodelling in both the trabecular meshwork in the anterior chamber and in the lamina cribrosa of the optic nerve head. Fibrosis in these regions leads to raised intraocular pressure and retinal ganglion cell degeneration, respectively. Lysophosphatidic acid (LPA) is a bioactive lipid mediator which acts via six G‐protein coupled receptors on the cell surface to activate intracellular pathways that promote cell proliferation, transcription and survival. LPA signalling has been implicated in both normal wound healing and pathological fibrosis. LPA enhances fibroblast proliferation, migration and contraction, and induces expression of pro‐fibrotic mediators such as connective tissue growth factor. The LPA axis plays a major role in diseases such as idiopathic pulmonary fibrosis, where it has been identified as an important pharmacological target. In glaucoma, LPA is present in high levels in the aqueous humour, and its signalling has been found to increase resistance to aqueous humour outflow through altered trabecular meshwork cellular contraction and extracellular matrix deposition. LPA signalling may, therefore, also represent an attractive target for treatment of glaucoma. In this review we wish to describe the role of LPA and its related proteins in tissue fibrosis and glaucoma.
Myofibroblast progeny in wound biology and wound healing studies
Authors: Monika Prakash , Waiker Prabhakar Veena , Chandraprabha Mathikere Naganna , Rangarajan Annapoorni , Murthy Kotamballi N. Chidambara 
Published: May 2021

AbstractFibroblasts and myofibroblasts play a myriad of important roles in human tissue function, especially in wound repair and healing. Among all cells, fibroblasts are group of cells that decide the status of wound as they maintain tissue homeostasis. Currently, the increase in the deleterious effects of chronic wound and their morbidity rate has necessitated the need to understand the influence of fibroblasts and myofibroblasts, which chiefly originate locally from tissue‐resident fibroblasts to address the same. Wound pathophysiology is complex, herein, we have discussed fibroblast and myofibroblast heterogeneity in skin and different organs by understanding the phenotypical and functional properties of each of its sub‐populations in the process of wound healing. Recent advancements in fibroblast activation, differentiation to myofibroblasts, proliferation and migration are discussed in detail. Fibroblasts and myofibroblasts are key players in wound healing and wound remodelling, respectively, and their significance in wound repair is discussed. An increased understanding of their biology during wound healing also gives an opportunity to explore more of fibroblast and myofibroblast focused therapies to treat chronic wounds which are clinical challenges. In this regard, in the current review, we have described the different methods for isolation of primary fibroblasts and myofibroblasts from both animal models and humans, and their characterization. Additionally, we have also provided details on possible molecular targets for better understanding of prognosis, diagnosis and treatment of chronic wounds. Information will help both researchers and clinicians in providing molecular insight that enable them for effective chronic wound management. The knowledge of intimate dialogue between the fibroblast, sub‐populations like, myofibroblast and their microenvironment, will serve useful in determining novel, efficient and specific therapeutic targets to treat pathological wound conditions.
Aerodynamic Loading Considerations of Three-Shaft Engine Compression System During Surge
Authors: Moreno Jose , Dodds John , Sheaf Christopher , Zhao Fanzhou , Vahdati Mehdi 
Published: May 2021

Abstract
Compressor surge imposes a limit on aero-engine operability and can compromise integrity because of significant aerodynamic loads imparted on the engine components. The aim of this article is to use 3D unsteady computational fluid dynamics (CFD) to predict the surge loadings on a compression system of a modern three-spool engine. The compression system is matched at a high power condition and computations are performed using a whole-assembly approach. In this study, the effect of two types of surge initiation on the maximum loading recorded during surge are studied: throttling of the high pressure compressor (HPC) and turning of the intermediate pressure compressor (IPC) variable stator vanes (VSV). An explanation of the main physical phenomena that contribute to those loadings is offered. It was found that in an aero-engine surge event, the maximum overpressure is driven by a combined effect of the surge shock wave passing and high pressure gas blown toward the front of the engine during depressurization. The amplitude of maximum overpressure is dictated by the compression system exit pressure at the moment of surge inception. The surge initiation via HPC throttling produces larger overpressure and therefore should be considered for design intent.
Ab Initio Investigation of the Elastic Properties of CaxSn1−x Alloys for Use As Battery Anodes
Authors: Woodcox Michael , Smeu Manuel 
Published: May 2021

Abstract
Density functional theory has been used to investigate 19 CaxSn1−x structures (six bulk materials and 13 alloys) as potential battery anodes. Of the alloys, we have found four stable phases (x = 0.25, 0.5, 0.625, and 0.75) and three metastable phases (two at x = 0.5 and one at x = 0.75). For the (meta)stable phases, we compare quantities such as the elastic moduli (bulk (K), shear (G), and Young’s (E)), Poisson’s ratio (ν) and the Pugh ratio (γ), the latter two being metrics for ductility. Nearly all of the alloys exhibit a steady increase in G (from 21.6 GPa to 25.3 GPa) and E (56.1 GPa to 59.1 GPa). K ranges from 25.7 GPa to 46.3 GPa across the same concentration window. For bulk Sn, the ν and γ values are close to the ductile/brittle boundary, followed by an increase in ductility to the peak value at x = 0.25 (ν = 0.298 and γ = 2.14), beyond which both quantities decrease reaching a minimum value at x = 0.75 (ν = 0.168 and γ = 1.17). The Debye temperature (θD) and minimum thermal conductivity (kmin) of each compound were also calculated, following a trend that is identical to the shear modulus. We have found that for stable/metastable compositions of CaxSn1−x, those sharing the same chemical composition (stoichiometry) also share remarkably similar material properties, indicating that such materials would be advantageous for uses in battery anodes.
A Numerical Approach Based on Finite Element Method for the Wrinkling Analysis of Dielectric Elastomer Membranes
Authors: Mao Guoyong , Hong Wei , Kaltenbrunner Martin , Qu Shaoxing 
Published: May 2021

Abstract
Dielectric elastomer (DE) actuators are deformable capacitors capable of a muscle-like actuation when charged. When subjected to voltage, DE membranes coated with compliant electrodes may form wrinkles due to the Maxwell stress. Here, we develop a numerical approach based on the finite element method (FEM) to predict the morphology of wrinkled DE membranes mounted on a rigid frame. The approach includes two steps: (I) pre-buckling and (II) post-buckling. In step I, the first buckling mode of the DE membrane is investigated by substituting the Maxwell stress with thermal stress in the built-in function of the FEM platform simulia abaqus. In step II, we use this first buckling mode as an artificial geometric imperfection to conduct the post-buckling analysis. For this purpose, we develop an equivalent model to simulate the mechanical behavior of DEs. Based on our approach, the thickness distribution and the thinnest site of the wrinkled DE membranes subjected to voltage are investigated. The simulations reveal that the crests/troughs of the wrinkles are the thinnest sites around the center of the membrane and corroborate these findings experimentally. Finally, we successfully predict the wrinkles of DE membranes mounted on an isosceles right triangle frame with various sizes of wrinkles generated simultaneously. These results shed light on the fundamental understanding of wrinkled dielectric elastomers but may also trigger new applications such as programmable wrinkles for optical devices or their prevention in DE actuators.
Habitual Caffeine Consumption Does Not Interfere With the Acute Caffeine Supplementation Effects on Strength Endurance and Jumping Performance in Trained Individuals
Authors: de Salles Painelli Vitor , Teixeira Emerson L. , Tardone Bruno , Moreno Marina , Morandini Jonatas , Larrain Victória H. , Pires Flávio O. 
Published: May 2021

The long-standing caffeine habituation paradigm was never investigated in strength endurance and jumping exercise performance through a straightforward methodology. The authors examined if habitual caffeine consumption would influence the caffeine ergogenic effects on strength endurance and jumping performance as well as perceptual responses. Thirty-six strength-trained individuals were mathematically allocated into tertiles according to their habitual caffeine consumption: low (20 ± 11 mg/day), moderate (88 ± 33 mg/day), and high consumers (281 ± 167 mg/day). Then, in a double-blind, crossover, counterbalanced fashion, they performed a countermovement vertical jump test and a strength endurance test either after caffeine (6 mg/kg) and placebo supplementation or after no supplementation (control). Perceptual responses such as ratings of perceived exertion and pain were measured at the termination of the exercises. Acute caffeine supplementation improved countermovement vertical jump performance (p = .001) and total repetitions (p = .004), regardless of caffeine habituation. Accordingly, analysis of absolute change from the control session showed that caffeine promoted a significantly greater improvement in both countermovement vertical jump performance (p = .004) and total repetitions (p = .0001) compared with placebo. Caffeine did not affect the rating of perceived exertion and pain in any exercise tests, irrespective of tertiles (for all comparisons, p > .05 for both measures). Caffeine side effects were similar in low, moderate, and high caffeine consumers. These results show that habitual caffeine consumption does not influence the potential of caffeine as an ergogenic aid in strength endurance and jumping exercise performance, thus challenging recommendations to withdraw from the habitual caffeine consumption before supplementing with caffeine.
Controls on andesitic glaciovolcanism at ice-capped volcanoes from field and experimental studies
Authors: Cole R.P. , White J.D.L. , Dürig T. , Büttner R. , Zimanowski B. , Bowman M.H. , Conway C.E. , Leonard G.S. , Pure L.R. , Townsend D.B. 
Published: May 2021

AbstractGlaciovolcanic deposits at Tongariro and Ruapehu volcanoes, New Zealand, represent diverse styles of interaction between wet-based glaciers and andesitic lava. There are iceconfined lavas, and also hydroclastic breccia and subaqueous pyroclastic deposits that formed during effusive and explosive eruptions into meltwater beneath the glacier; they are rare among globally reported products of andesitic glaciovolcanism. The apparent lack of hydrovolcanically fragmented andesite at ice-capped volcanoes has been attributed to a lack of meltwater at the interaction sites because either the thermal characteristics of andesite limit meltwater production or meltwater drains out through leaky glaciers and down steep volcano slopes. We used published field evidence and novel, dynamic andesite-ice experiments to show that, in some cases, meltwater accumulates under glaciers on andesitic volcanoes and that meltwater production rates increase as andesite pushes against an ice wall. We concur with models for eruptions beneath ice sheets showing that the glacial conditions and pre-eruption edifice morphology are more important controls on the style of glaciovolcanism and its products than magma composition and the thermal properties of magmas. Glaciovolcanic products can be useful proxies for paleoenvironment, and the range of andesitic products and the hydrological environments in which andesite erupts are greater than hitherto appreciated.
Tectonostratigraphic record of late Miocene–early Pliocene transtensional faulting in the Eastern California shear zone, southwestern USA
Authors: Dorsey Rebecca J. , O’Connell Brennan , Gardner Kevin K. , Homan Mindy B. , Bennett Scott E.K. , Thacker Jacob O. , Darin Michael H. 
Published: May 2021

AbstractThe Eastern California shear zone (ECSZ; southwestern USA) accommodates ~20%–25% of Pacific–North America relative plate motion east of the San Andreas fault, yet little is known about its early tectonic evolution. This paper presents a detailed stratigraphic and structural analysis of the uppermost Miocene to lower Pliocene Bouse Formation in the southern Blythe Basin, lower Colorado River valley, where gently dipping and faulted strata provide a record of deformation in the paleo-ECSZ. In the western Trigo Mountains, splaying strands of the Lost Trigo fault zone include a west-dipping normal fault that cuts the Bouse Formation and a steeply NE-dipping oblique dextral-normal fault where an anomalously thick (~140 m) section of Bouse Formation siliciclastic deposits filled a local fault-controlled depocenter. Systematic basinward thickening and stratal wedge geometries in the western Trigo and southeastern Palo Verde Mountains, on opposite sides of the Colorado River valley, record basinward tilting during deposition of the Bouse Formation. We conclude that the southern Blythe Basin formed as a broad transtensional sag basin in a diffuse releasing stepover between the dextral Laguna fault system in the south and the Cibola and Big Maria fault zones in the north. A palinspastic reconstruction at 5 Ma shows that the southern Blythe Basin was part of a diffuse regional network of linked right-stepping dextral, normal, and oblique-slip faults related to Pacific–North America plate boundary dextral shear. Diffuse transtensional strain linked northward to the Stateline fault system, eastern Garlock fault, and Walker Lane, and southward to the Gulf of California shear zone, which initiated ca. 7–9 Ma, implying a similar age of inception for the paleo-ECSZ.
The value of anal swab RT-PCR for COVID-19 diagnosis in adult Indonesian patients
Authors: Abdullah Murdani , Sudrajat Dedy Gunawanjati , Muzellina Virly Nanda , Kurniawan Juferdy , Rizka Aulia , Utari Amanda Pitarini , Pribadi Rabbinu Rangga , Idrus Muhammad Firhat , Yusra Yusra , Meilany Sofy , Surandy Andry , Shatri Hamzah , Rinaldi Ikhwan , Pitoyo Ceva Wicaksono , Renaldi Kaka 
Published: May 2021

ObjectiveThis study will test the performance of the anal swab PCR test when compared with the nasopharyngeal swab PCR test as a diagnostic tool for COVID-19.DesignAn observational descriptive study which included hospitalised suspected, or probable cases of hopitalised COVID-19 patients, conducted in Dr. Cipto Mangunkusumo National Hospital, Ciputra Hospital, Mitra Keluarga Depok Hospital and Mitra Keluarga Kelapa Gading Hospital, Indonesia. Epidemiological, clinical, laboratory and radiology data were obtained. Nasopharyngeal and anal swabs specimens were collected for SARS-CoV-2 RNA detection.ResultsWe analysed 136 subjects as part of this study. The clinical spectrum of COVID-19 manifesation in this study was typical of hospitalised patients, with 25% classified as mild cases, 14.7% in severe condition and 12.5% of subjects classified as having acute respiratory distress syndrome. When compared with nasopharyngeal swab as the standard specimen for reverse transcription polymerase chain reaction (RT-PCR) detection of SARS-CoV-2 antigen, the sensitivity and specificity of the anal swab was 36.7% and 93.8%, respectively. The positive and negative predictive value were 97.8% and 16.5 %, respectively. The performance of the anal swab remained similar when only the subgroup of patients with gastrointestinal symptoms (n=92, 67.6%) was analysed (sensitivity 40% and specificity 91.7%). Out of all the subjects included in analysis, 67.6% had gastrointestinal symptoms. Similarly, 73.3% of patients in the anal swab-positive group had gastrointestinal symptoms. The two most common gastrointestinal symptoms in the subjects’ population were nausea and anorexia.ConclusionAnal swab specimen has low sensitivity (36.7%) but high specificity (93.8%) for detecting SARS-CoV-2 antigen by RT-PCR. Only one additional positive result was found by anal swab among the nasopharyngeal swab-negative group. Anal swab may not be needed as an additional test at the beginning of a patient’s diagnostic investigation and nasopharyngeal swab RT-PCR remains as the standard diagnostic test for COVID-19.
Uncovering undiagnosed liver disease: prevalence and opportunity for intervention in a population attending colonoscopy
Authors: Koo Sara , Sharp Linda , Hull Mark , Rushton Steven , Neilson Laura J ,   The OSCAR study team, McPherson Stuart , Rees Colin J 
Published: May 2021

ObjectiveDue to high rates of obesity and alcohol consumption, the prevalence of fatty liver disease is increasing. There is no widely adopted approach to proactively screen for liver disease in the community. We aimed to assess the burden of potentially undiagnosed liver disease in individuals attending for colonoscopy to develop a pathway to identify and manage individuals with undiagnosed liver disease.DesignThe OSCAR Study was a cross-sectional study recruiting patients attending for colonoscopy. Patients’ metabolic and liver risk factors were measured. The prevalence of undiagnosed significant fatty liver disease was measured using the Fatty Liver Index (FLI) and Fibrosis-4 score (FIB-4).Results1429 patients (mean age 59±14 years; 48.8% men) were recruited. 73.3% were overweight/obese, 12.7% had diabetes and 17.9% had metabolic syndrome. 19% were consuming more than recommenced alcohol levels (<14 units/week) and 41% had an AUDIT-C score ≥5. After excluding those with known liver disease, 43.2% of the cohort had a high FLI (high likelihood of fatty liver). 5.3% of these had a high FIB-4 score (>2.67, high probability of advanced fibrosis) and 90% of these were previously undiagnosed. 818 patients had a predicted 10-year cardiovascular event risk of ≥10%, however only 377 (46.1%) were on statin therapy.ConclusionHigh levels of obesity, metabolic dysfunction and undiagnosed fatty liver disease were found in individuals attending for colonoscopy. Clinical encounters in the endoscopy unit may represent an opportunity to risk assess for liver and metabolic disease and provide an environment to develop targeted interventions.
HPV self-sampling for cervical cancer screening: a systematic review of values and preferences
Authors: Nishimura Holly , Yeh Ping Teresa , Oguntade Habibat , Kennedy Caitlin E , Narasimhan Manjulaa 
Published: May 2021

IntroductionThe WHO recommends human papillomavirus (HPV) cervical self-sampling as an additional screening method and HPV DNA testing as an effective approach for the early detection of cervical cancer for women aged ≥30 years. This systematic review assesses end user’s values and preferences related to HPV self-sampling.MethodsWe searched four electronic databases (PubMed, Cumulative Index to Nursing and Allied Health Literature, Latin American and Caribbean Health Sciences Literature and Embase) using search terms for HPV and self-sampling to identify articles meeting inclusion criteria. A standardised data extraction form was used to capture study setting, population, sample size and results related to values and preferences.ResultsOf 1858 records retrieved, 72 studies among 52 114 participants published between 2002 and 2018 were included in this review. Almost all studies were cross-sectional surveys. Study populations included end users who were mainly adolescent girls and adult women. Ages ranged from 14 to 80 years. Most studies (57%) were conducted in high-income countries. Women generally found HPV self-sampling highly acceptable regardless of age, income or country of residence. Lack of self-confidence with collecting a reliable sample was the most commonly cited reason for preferring clinician-collected samples. Most women preferred home-based self-sampling to self-sampling at a clinic. The cervical swab was the most common and most accepted HPV DNA sampling device.ConclusionsHPV self-sampling is generally a highly accepted method of cervical cancer screening for end users globally. End user preferences for self-sampling device, method and setting can inform the development of new and expanded interventions to increase HPV screening.
Determinants of healthcare use based on the Andersen model: a study protocol for a systematic review of longitudinal studies
Authors: Hajek André , Kretzler Benedikt , König Hans-Helmut 
Published: May 2021

IntroductionA previous systematic review published in 2012 focused on the use of health services based on the Andersen model. Extending this review, we will exclusively focus on systematically synthesising longitudinal studies examining the determinants of healthcare use based on the Andersen model. Therefore, our aim of this systematic review is to provide an overview of longitudinal observational studies investigating the predictors of healthcare use explicitly using this model.Methods and analysisWe will search three electronic databases (Medline, PsycINFO and CINAHL). Furthermore, reference lists will be searched manually. Longitudinal observational studies will be investigating the determinants of healthcare use (in terms of use of outpatient physician services (like general practitioner’s visits or specialist visits in total) and hospitalisation). We will exclude disease-specific samples. Data extraction will focus on methods (eg, assessment of healthcare use), sample characteristics and main findings. A suitable tool will be used to assess the study quality. Study selection, data extraction and evaluation of study quality will be conducted by two reviewers. The findings will be presented by means of figures, summary tables, narrative summaries and meta-analysis (if possible).Ethics and disseminationNo primary data will be collected. Therefore, approval by an ethics committee is not required. Our findings are planned to be published in a peer-reviewed journal.PROSPERO registration numberCRD42020193198.