bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plastic Biaxial Stress-Strain Relations for Alcoa 24S-T Subjected to Variable-Stress Ratios
Authors: Marin Joseph , Kotalik B. J. 
Published: April 2021

Abstract
Usually plastic biaxial stress-strain relations for metals have been determined for tests in which the ratios of the principal stresses have been maintained essentially constant. This paper presents biaxial plastic stress-strain relations for both constant and variable-stress ratios. The purpose of conducting the variable-stress-ratio tests is to attempt to prove whether the flow- or deformation-type theory is the correct theory for predicting plastic stress-strain relations. The paper also gives a comparison between the actual and theoretically predicted values of the biaxial yield, ultimate and fracture strengths, and the biaxial ductility. Various ratios of biaxial tensile stresses were investigated by subjecting tubular specimens to axial tension and internal pressure. The test results showed that the yield-strength values agree best with the distortion-energy theory. For the prediction of the plastic stress-strain relations the deformation-type theory was found to be in approximate agreement with the test results for both the constant- and variable-stress-ratio tests.
Elastic Torsion in the Presence of Initial Axial Stress
Authors: Goodier J. N. 
Published: April 2021

Abstract
The torsional rigidity, for small elastic torsion, of bars of thin-walled open section, is, in general, altered by initial tension, compression, bending, or other axial stress. This appears in the increase of torsional stiffness of strips due to tension, in the decrease to zero in open sections which buckle torsionally as columns, and also has an influence on lateral buckling of beams. This paper contains an extension of the Saint Venant solution for ordinary torsion to the problem of torsion in the presence of initial axial stress with any distribution on the cross section. The results are confirmed by tests, and validate the intuitively derived formulas which are in use.
The Uniform Distribution of a Fluid Flowing Through a Perforated Pipe
Authors: Dow Willard M. 
Published: April 2021

Abstract
A theoretical analysis is made of the flow through a perforated pipe with a closed end for the special case of a constant linear rate of discharge along the length of the pipe. The results of the fluid-flow considerations are applicable to many practical manifold systems. The practical significance of the results with respect to pipe burners for gaseous fuels is emphasized as the results make possible the design of simple high-capacity and extended-range pipe burners of industrial importance. The capacity of commercially available pipe burners may be increased several hundred per cent. The validity of the theoretical results was verified by experiment.
Measurements of Diffraction of Shock Waves and Resulting Loading of Structures
Authors: Bleakney Walker , White D. R. , Griffith W. C. 
Published: April 2021

Abstract
Although the idea of using a shock tube to generate waves of large amplitude and to study their properties is not new, nevertheless this technique has been improved greatly in recent years. This circumstance, taken together with good optical methods of measurement, has provided a powerful tool for the investigation of a great variety of problems in transient interactions of shocks and fluid flows with solid objects and with each other. This paper is concerned with the evolution in time of a flow pattern about an obstacle initially in still air, passed over by a sudden front of high-speed flow induced by a shock wave, the stream approaching a steady configuration. Such information is not only of interest in the theory of fluid dynamics but it also is of considerable practical importance, since the principal forces on the obstacle can be measured as a function of time, and the character of the loading determined. The main objective of this paper is to elucidate the method by giving examples of a great variety of experiments and at the same time to provide a large amount of basic data which may be used by others in various types of analyses.
The Use of Skewed Rolls in Calendering Operations
Authors: Carrier G. F. 
Published: April 2021

Abstract
In many commercial operations it is desirable to produce a uniform sheet of material by passing the viscous raw ingredients through rotating cylindrical rolls. With rolls supported at the ends only there is danger of wide variations in thickness of the finished product. This may be overcome by “skewing” the rolls the amount necessary for any given thickness and material properties. This paper presents an analytical approach to determining the optimum operating position of the rolls.
A Mathematical Representation of the Wheatley Heart Valve
Authors: McKee S. , Cuminato J. A. , Stewart I. W. , Wheatley D. J. 
Published: April 2021

Abstract
Starting from a hand-drawn contour plot, this note develops a set of intersecting and contiguous circles whose perimeter, upon extending appropriately to three dimensions, can be seen to be a natural mathematical representation of the Wheatley heart valve.
Ductile Damage Model Based on Void Growth Analysis for Application to Ductile Crack Growth Simulation
Authors: Yamada Takehisa , Ohata Mitsuru 
Published: April 2021

AbstractThis study aims to propose the damage model based on of the mechanism for ductile fracture related to void growth and to confirm the applicability of the proposed model to ductile crack growth simulation for steel. To figure out void growth behavior, elastoplastic finite element analyses using a unit cell model with an initial void were methodically performed. From the results of those analyses, it was evident that the relationships between normalized void volume fraction and normalized strain by each critical value corresponding to crack initiation were independent of stress–strain relationship of material and stress triaxiality state. Based on this characteristic associated with void growth, damage evolution law was derived. Then, using the damage evolution law, simple and phenomenological ductile damage model reflecting void growth behavior and ductility of material was proposed. To confirm the validation and application of the proposed damage model, the damage model was implemented in finite element models and ductile crack growth resistance was simulated for cracked components were performed. Then, the simulated results were compared with experimental ones and it was found that the proposed damage model could accurately predict ductile crack growth resistance and applied to ductile crack growth simulation.
Structural Integrity Assessment of Defected Gas Pipelines Using a Simplified Ductile Damage Model
Authors: Kim Ik-Joong , Kim Cheol-Man , Baek Jong-Hyun , Kim Young-Pyo , Lee Youngseog , Jang Yun-Chan 
Published: April 2021

Abstract
The finite element method using the damage model has been increasingly used to predict the failure of various structures. Thus, various damage models were presented, and recently, a phenomenological model called the local fracture strain model was presented, making it easy and accurate to predict the damage of the structure. This model has the advantage of defining fracture strain as a function of stress triaxiality with only a few notched tensile tests but has a limitation because it does not consider the damage evolution because of the void growth. This study presents an enhanced damage model that improves the accuracy of the failure simulation of defected structures by adding a parameter that considers stiffness degradation according to void growth to the damage model based on the fracture strain. Therefore, loading–unloading tests were conducted and the damage index of fracture was identified using a three-dimensional digital image correlation system. The failure simulation results using the proposed damage model were compared with experimental, such as notched tensile, single edge notched tension (SENT), and full-scale burst tests.
Extensive decentralized hydrogen export from the Atlantis Massif
Authors: Lang Susan Q. , Lilley Marvin D. , Baumberger Tamara , Früh-Green Gretchen L. , Walker Sharon L. , Brazelton William J. , Kelley Deborah S. , Elend Mitchell , Butterfield David A. , Mau Aaron J. 
Published: April 2021

Abstract
Hydrogen is an important energy source for subsurface microbial communities, but its availability beyond the flow focused through hydrothermal chimneys is largely unknown. We report the widespread export of H2 across the Atlantis Massif oceanic core complex (30°N, Mid-Atlantic Ridge; up to 44 nM), which is distinct from the circulation system feeding the Lost City Hydrothermal Field (LCHF) on the massif's southern wall. Methane (CH4) abundances are generally low to undetectable (&lt;3 nM) in fluids that are not derived from the LCHF. Reducing fluids exit the seafloor over a wide geographical area and depth range, including the summit of the massif and along steep areas of mass wasting east of the field. The depth of the fluids in the water column and their H2/CH4 ratios indicate that some are sourced separately from the LCHF. We argue that extensive H2 export is the natural consequence of fluid flow pathways strongly influenced by tectonic features and the volume and density changes that occur when ultramafic rocks react to form serpentinites, producing H2 as a by-product. Furthermore, the circulation of H2-rich fluids through uplifted mantle rocks at moderate temperatures provides geographically expansive and stable environmental conditions for the early evolution of biochemical pathways. These results provide insight into the spatial extent of H2- and CH4-bearing fluids associated with serpentinization, independent of the focused flow emanating from the LCHF.
Similar curvature-to-width ratios for channels and channel belts: Implications for paleo-hydraulics of fluvial ridges on Mars
Authors: Hayden Alistair T. , Lamb Michael P. , Carney Alexander J. 
Published: April 2021

AbstractThe surface of Mars contains abundant sinuous ridges that appear similar to river channels in planform, but they stand as topographic highs. Ridges have similar curvature-to-width ratios as terrestrial meandering rivers, which has been used to support the hypothesis that ridges are inverted channels that directly reflect channel geometry. Anomalously wide ridges, in turn, have been interpreted as evidence for larger rivers on Mars compared to Earth. However, an alternate hypothesis is that ridges are exhumed channel-belt deposits— a larger zone of relatively coarse-grained deposits formed from channel lateral migration and aggradation. Here, we measured landform wavelength, radius of curvature, and width to compare terrestrial channels, terrestrial channel belts, and martian ridges. We found that all three landforms follow similar scaling relations, in which ratios of radius of curvature to width range from 1.7 to 7.3, and wavelength-to-width ratios range from 5.8 to 13. We interpret this similarity to be a geometric consequence of a sinuous curved line of finite width. Combined with observations of ridge-stacking patterns, our results suggest that wide ridges on Mars could indicate fluvial channel belts that formed over significant time rather than anomalously large rivers.
Nitrogen Heterosubstitution in Graphene Nanoflakes: An Effective Approach to Improving Performance of Supercapacitors with Ionic Liquid Electrolyte
Authors: Arkhipova E. A. , Ivanov A. S. , Maslakov K. I. , Chernyak S. A. , Savilov S. V. 
Published: April 2021

Abstract
Nitrogen-doped graphene nanoflakes with a high nitrogen content (6.6 at %) and developed mesoporosity were synthesized via pyridine pyrolysis. They were tested in a supercapacitor with a non-aqueous electrolyte: a 1.2 M solution of ionic liquid Et4N+TFSI− in acetonitrile. It was found that incorporation of nitrogen into the graphene layers nearly tripled the specific capacitance of the electrode, compared to the undoped nanoflakes.
Comparison of identifiable and non-identifiable data linkage: health technology assessment of MitraClip using registry, administrative and mortality datasets
Authors: Keltie Kim , Cognigni Paola , Gross Sam , Urwin Samuel , Burn Julie , Cole Helen , Berry Lee , Patrick Hannah , Sims Andrew 
Published: April 2021

ObjectivesThe UK MitraClip registry was commissioned by National Health Service (NHS) England to assess real-world outcomes from percutaneous mitral valve repair for mitral regurgitation using a new technology, MitraClip. This study aimed to determine longitudinal patient outcomes by linking to routine datasets: Hospital Episode Statistics (HES) Admitted Patient Care (APC) and Office of National Statistics.MethodsTwo methods of linkage were compared, using identifiable (NHS number, date of birth, postcode, gender) and non-identifiable data (hospital trust, age in years, admission, discharge and operation dates, operation and diagnosis codes). Outcome measures included: matching success, patient demographics, all-cause mortality and subsequent cardiac intervention.ResultsA total of 197 registry patients were eligible for matching with routine administrative data. Using identifiable linkage, a total of 187 patients (94.9%) were matched with the HES APC dataset. However, 21 matched individuals (11.2%) had inconsistencies across the datasets (eg, different gender) and were subsequently removed, leaving 166 (84.3%) for analysis. Using non-identifiable data linkage, a total of 170 patients (86.3%) were uniquely matched with the HES APC dataset.Baseline patient characteristics were not significantly different between the two methods of data linkage. The total number of deaths (all causes) identified from identifiable and non-identifiable linkage methods was 37 and 40, respectively, and the difference in subsequent cardiac interventions identified between the two methods was negligible.ConclusionsPatients from a bespoke clinical procedural registry were matched to routine administrative data using identifiable and non-identifiable methods with equivalent matching success rates, similar baseline characteristics and similar 2-year outcomes.
Digital health interventions for the management of mental health in people with chronic diseases: a rapid review
Authors: Sasseville Maxime , LeBlanc Annie , Boucher Mylène , Dugas Michèle , Mbemba Gisele , Tchuente Jack , Chouinard Maud-Christine , Beaulieu Marianne , Beaudet Nicolas , Skidmore Becky , Cholette Pascale , Aspiros Christine , Larouche Alain , Chabot Guylaine , Gagnon Marie-Pierre 
Published: April 2021

ObjectiveDetermine the effectiveness of digital mental health interventions for individuals with a concomitant chronic disease.DesignWe conducted a rapid review of systematic reviews. Two reviewers independently conducted study selection and risk of bias evaluation. A standardised extraction form was used. Data are reported narratively.InterventionsWe included systematic reviews of digital health interventions aiming to prevent, detect or manage mental health problems in individuals with a pre-existing chronic disease, including chronic mental health illnesses, published in 2010 or after.Main outcome measureReports on mental health outcomes (eg, anxiety symptoms and depression symptoms).ResultsWe included 35 reviews, totalling 702 primary studies with a total sample of 50 692 participants. We structured the results in four population clusters: (1) chronic diseases, (2) cancer, (3) mental health and (4) children and youth. For populations presenting a chronic disease or cancer, health provider directed digital interventions (eg, web-based consultation, internet cognitive–behavioural therapy) are effective and safe. Further analyses are required in order to provide stronger recommendations regarding relevance for specific population (such as children and youth). Web-based interventions and email were the modes of administration that had the most reports of improvement. Virtual reality, smartphone applications and patient portal had limited reports of improvement.ConclusionsDigital technologies could be used to prevent and manage mental health problems in people living with chronic conditions, with consideration for the age group and type of technology used.
Can non-responders be ‘rescued’ by increasing exercise intensity? A quasi-experimental trial of individual responses among humans living with pre-diabetes or type 2 diabetes mellitus in Canada
Authors: Hrubeniuk Travis J , Bouchard Danielle R , Gurd Brendon J , Sénéchal Martin 
Published: April 2021

IntroductionExercise is recommended to improve glycaemic control. Yet, individual changes in glycaemic control following exercise can vary greatly, meaning while some significantly improve others, coined ‘non-responders’, do not. Increasing the intensity of exercise may ‘rescue’ non-responders and help generate a response to training. This trial will identify non-responders to changes in glycated haemoglobin (HbA1c) across inactive individuals living with pre-diabetes or type 2 diabetes mellitus following an aerobic exercise programme and evaluate if increasing training intensity will elicit beneficial changes to ‘rescue’ previously categorised non-responders.Methods and analysisThis study will recruit 60 participants for a two-phase aerobic exercise training programme. Participants will be allocated to a control group or assigned to an intervention group. Control participants will maintain their current lifestyle habits. During phase 1, intervention participants will complete 16 weeks of aerobic exercise at an intensity of 4.5 metabolic equivalents (METs) for 150 min per week. Participants will then be categorised as responders or non-responders based on the change in HbA1c. For phase 2, participants will be blocked based on responder status and randomly allocated to a maintained intensity, or increased intensity group for 12 weeks. The maintained group will continue to train at 4.5 METs, while the increased intensity group will train at 6.0 METs for 150 min per week.Ethics and disseminationResults will be presented at scientific meetings and submitted to peer-reviewed journals. Publications and presentations related to the study will be authorised and reviewed by all investigators. Findings from this study will be used to provide support for future randomised control trials. All experimental procedures have been approved by the Research Ethics Board at the University of New Brunswick (REB: 2018–168).Trial registration numberNCT03787836.
PAID study design on the role of PKC activation in immune/inflammation-related depression: a randomised placebo-controlled trial protocol
Authors: Guo Xiaoyun , Mao Ruizhi , Cui Lvchun , Wang Fan , Zhou Rubai , Wang Yun , Huang Jia , Zhu Yuncheng , Yao Yamin , Zhao Guoqing , Li Zezhi , Chen Jun , Wang Jinhui , Fang Yiru 
Published: April 2021

BackgroundInflammation that is mediated by microglia activation plays an important role in the pathogenesis of depression. Microglia activation can lead to an increase in the levels of proinflammatory cytokines, including TNF-α, which leads to neuronal apoptosis in the specific neural circuits of some brain regions, abnormal cognition and treatment-resistant depression (TRD). Protein kinase C (PKC) is a key regulator of the microglia activation process. We assume that the abnormality in PKC might result in abnormal microglia activation, neuronal apoptosis, significant changes in emotional and cognitive neural circuits, and TRD. In the current study, we plan to target at the PKC signal pathway to improve the TRD treatment outcome.Methods and analysisThis is a 12-week, ongoing, randomised, placebo-controlled trial. Patients with TRD (N=180) were recruited from Shanghai Mental Health Center, Shanghai Jiao Tong University. Healthy control volunteers (N=60) were recruited by advertisement. Patients with TRD were randomly assigned to ‘escitalopram+golimumab (TNF-α inhibitor)’, ‘escitalopram+calcium tablet+vitamin D (PKC activator)’ or ‘escitalopram+placebo’ groups. We define the primary outcome as changes in the 17-item Hamilton Depression Rating Scale (HAMD-17). The secondary outcome is defined as changes in anti-inflammatory effects, cognitive function and quality of life.DiscussionThis study might be the first randomised, placebo-controlled trial to target at the PKC signal pathway in patients with TRD. Our study might help to propose individualised treatment strategies for depression.Trial registration numberThe trial protocol is registered with ClinicalTrials.gov under protocol ID 81930033 and ClinicalTrials.gov IDNCT04156425.
Multi-gene custom panels for the characterisation of metastatic colorectal carcinoma in clinical practice: express the role ofPIK3CAmutations
Authors: de Biase Dario , Malapelle Umberto , De Leo Antonio , Maloberti Thais , Visani Michela , Pisapia Pasquale , Acquaviva Giorgia , Pepe Francesco , Russo Gianluca , Iaccarino Antonino , Pession Annalisa , Tallini Giovanni , Troncone Giancarlo 
Published: April 2021

AimsIn metastatic colorectal carcinomas (mCRC),RAS/RAFgenes mutations are first tested to determine the eligibility for anti-EGFR (Epidermal Growth Factor Receptor) therapy in combination with conventional cytotoxic agents. Recent advancements in next-generation sequencing (NGS) have highlighted the potential of multi-gene panels. This multi-gene analysis may provide useful information for the molecular characterisation of mCRC, other than the status ofRAS/RAFgenes. Aim of this study was to evaluate the feasibility of two NGS custom multi-gene panels in the characterisation of CRC cases and evaluating the relevance ofPIK3CAmutation in a routine cohort of consecutive CRC cases.MethodsA total of 961 formalin-fixed and paraffin-embedded specimens from two medical centres (Bologna and Naples) were analysed using two lab-developed NGS multi-gene panels.ResultsKRASmutations (56.2%) were the more frequent alterations observed in our cohort. Intriguingly,PIK3CAmutations were more frequent (16.8%) than variants observed in the other two genes nowadays analysed in CRC clinical practice (NRASandBRAF, 4.2% and 9.6%, respectively). Moreover, in more than 10% of samples, coexistent mutations were detected in our cohort of CRC.ConclusionsOur study demonstrates the feasibility and efficacy of lab-developed targeted multi-gene NGS panels in the clinical practice of CRC. Moreover, the data lead to hypothesise thatPIK3CAmutations, together with those ofRAS/BRAF, worth to be further investigated in clinical CRC specimens.