bluuebunny/crossref_metadata_2025 huggingface dataset:
Wear of Bulk Metallic Glass Alloys for Space Mechanism Applications
Authors: Murphy A. G. , Norman A. , Meagher P. , Browne D. J.
Published: March 2022

Space-based mechanisms must operate under harsh environments, usually without access for maintenance; failure may result in a loss of a spacecraft. Therefore, space agencies support research on high-performance mechanism designs and materials, one key area being space tribology. Bulk metallic glasses (BMGs) are a class of alloy characterized by their amorphous structure, which results in a material with extremely high strength, corrosion resistance, high hardness, and high elastic limit. BMGs have demonstrated improved wear resistance when compared against traditional engineering materials in similar applications. Four BMG compositions, Zr53Al16Co23.25Ag7.75, Zr49Ti1.96Cu37.24Al9.8Y2, Zr60Ti2Nb2Al7.5Ni10Cu18.5, and Cu47Zr46Al5Y2 (at%), were selected from the literature as potential candidates for space-based mechanisms applications. Wear testing, hardness, profilometry, and scanning electron microscopy (SEM)/energy dispersive X-ray (EDX) spectroscopy analysis were performed on the selected alloys, and their results were compared. High-resolution 3D profilometry and detailed image analysis of wear tracks and volume loss resulted in a critical re-assessment of the Archard wear coefficient. For the compositions tested, the hardness was not a useful predictor of the wear performance as suggested by the Archard wear equation. Processing history and test configuration significantly influenced the wear behavior. The alloy Zr49Ti1.96Cu37.24Al9.8Y2 was found to be the best BMG candidate for space wear applications when taking manufacturability into consideration. BMG hardness and wear test results were compared with similar testing performed on conventional crystalline alloys commonly used in space applications: titanium alloy Ti-6Al-4V ELI, and cold-worked stainless steels AISI 303 and AISI 304.
Low Reynolds Number Effects on the Separation and Wake of a Compressor Blade
Authors: Liu Qiang , Ager Will , Hall Cesare , Wheeler Andrew P.S.
Published: March 2022

This paper investigates the surface boundary layer and wake development of a compressor blade at a range of low Reynolds number from 45,000 to 120,000. Experiments in a miniature linear compressor cascade facility have been performed with detailed surface pressure measurements and flow visualization to track variations in the separation bubble size. These have been combined with high-resolution pneumatic pressure and hot-wire probe traverses in the downstream wake. High-fidelity direct numerical simulations have been completed on the same compressor blade section across the same range of operating conditions. The results show that large laminar separation bubbles exist on both blade surfaces. As Reynolds number increases, these separation bubbles shorten in length and reduce in thickness. Correspondingly, the downstream wake narrows, although the peak wake loss coefficient remains approximately constant. As the Reynolds number is increased from 45,000 to 120,000, the bubble length on the suction side reduced from 48% to 28% chord and on the pressure side reduced from 35% to 20% chord, while the loss coefficient reduced from 9% to 5%. The flow features are examined further within the high-fidelity computations, which reveal the dependence of the wake turbulence on the laminar separation bubbles. The separation bubbles are found to generate turbulent kinetic energy, which convects downstream to form the outer part of wake. As Re increases, a shorter bubble produces less turbulence in the outer part of the boundary layer leading to a narrower wake. However, the trailing edge separation is largely independent of Reynolds number, leading to the constant peak loss coefficient observed. The overall loss is shown to vary linearly with the total turbulence production, and this depends on the size of the separation bubbles. Overall, this research provides new insight into the connection between the blade surface flow field and the wake characteristics at low Reynolds number. The findings suggest that changes that minimize the extent of the blade separation bubbles could provide significant improvements to both the steady and unsteady properties of the wake.
Digitizing Product Dissection: A Case Study on Augmented Reality and Animation in Engineering Education
Authors: Kearney Kevin G. , Starkey Elizabeth M. , Miller Scarlett R.
Published: March 2022

The global pandemic of 2020 caused a paradigm shift in engineering education. In a matter of weeks, and sometimes days, faculty members across the world had to move their hands-on engineering courses to an online environment. During this shift, educators relied on technology more so than ever to improve student design learning without an empirically understanding of the impact of this shift on students' cognition and understanding. The current study was developed to determine the cognitive underpinnings of such shifts by exploring the impact of Augmented Reality (AR) and animation impact engineering student learning, cognitive load, and recall during a virtual product dissection educational activity. This was achieved through a full factorial experiment with 117 first-year engineering students where students were divided into one of four conditions: baseline of virtual dissection; virtual dissection + animation, AR dissection, and AR dissection + animation. The results of the study show that students in the virtual dissection + animation showed an increased understanding of the product over the three other conditions. In addition, participant cognitive load and recall in the AR condition were not significantly different than in a non-AR virtual environment. The results are used to provide recommendations on how technology can be utilized in a virtual classroom environment, providing crucial insight into the steps needed to virtualize engineering education during the pandemic as well as future steps toward possible education reform.
Reliability-Informed Economic and Energy Evaluation for Bi-Level Design for Remanufacturing: A Case Study of Transmission and Hydraulic Manifold
Authors: Nemani Venkat P. , Liu Jinqiang , Ahmed Navaid , Cartwright Adam , Kremer Gül E. , Hu Chao
Published: March 2022

Design for remanufacturing (DfRem) is one attractive strategy that encourages the reuse of a product and extends the product's life cycle. Traditional design processes often only consider product reliability at an early design stage. However, from the perspective of environmental sustainability, it is becoming increasingly important to evaluate the long-term economic and environmental impacts of design decisions during early-stage design. We propose a bi-level DfRem framework consisting of system-level reusability allocation and component-level design tradeoff analysis, considering reliability and product warranty policy. First, a system-level reusability allocation problem aims at a theoretical exploration of the design space where all the components comprising the system are allocated certain reuse rates to achieve target energy savings with minimum cost. Following the theoretical exploration at the system level, a component-level analysis looks at practical design options for each component and trades-off between the overall cost and energy consumption for multiple remanufacturing cycles. Both levels of the framework require modeling component reuse for multiple remanufacturing cycles, which we achieve by using a branched power-law model that provides probabilistic scenarios of reusing the component or replacing it with a new part. We demonstrate the utility of this framework with the case study of an infinitely variable transmission (IVT) used by some agricultural machines manufactured by John Deere and show snapshots of a prototype software tool that we developed for easy use by designers.
Multidimensional Computational Fluid Dynamics Combustion Process Modeling of a 6V150 Diesel Engine
Authors: Liu Zhentao , Zhang Yu , Fu Jiahong , Liu Jinlong
Published: March 2022

The smart diesel program requires the engine electronic control unit to consider additional parameters, such as altitude and climatic conditions, in the mapping calibration process. A specially designed environmental simulation cabin, which can simulate environmental conditions at any longitude and dimension, would allow dynamometer testing to be performed indoors. Considering its high cost, a three-dimensional (3D) computational fluid dynamics (CFD) is needed to guide and/or complement experimental researches. As a result, the main objective of this study was to establish a 3D RANS model (i.e., reasonable computational cost and running time) that can provide in-cylinder details and predict the efficiency of a 6V150 diesel engine under varied operating conditions. A sector mesh approach was employed, considering only the compression, combustion, and expansion periods from intake valve closing to exhaust valve opening. The results indicated that the model simulated cylinder pressure agreed well with the experimental data, with relative errors of less than 6% during the primary compression, combustion, and expansion. Further, the model predicted heat release phasing was inconsistent with the experimental results, with absolute errors of less than one crank angle degree for peak pressure location, CA50, and ignition delay. In addition, the multidimensional model captured the effects of environmental pressure and temperature on spray formation (i.e., the dominant phenomenological event). Moreover, the model reasonably reproduced the effects of engine control variables on performance and emissions. All these observations demonstrated the validity of the selection and calibration of geometry, chemistry, and submodels including turbulence, spray, heat transfer, combustion, etc. Overall, the model was deemed capable of predicting combustion characteristics under extreme conditions, including high-temperature, high-cold, and high-altitude environments, which can facilitate the development of smart engines.
Extended high-frequency audiometry in research and clinical practice
Authors: Lough Melanie , Plack Christopher J.
Published: March 2022

Audiometric testing in research and in clinical settings rarely considers frequencies above 8 kHz. However, the sensitivity of young healthy ears extends to 20 kHz, and there is increasing evidence that testing in the extended high-frequency (EHF) region, above 8 kHz, might provide valuable additional information. Basal (EHF) cochlear regions are especially sensitive to the effects of aging, disease, ototoxic drugs, and possibly noise exposure. Hence, EHF loss may be an early warning of damage, useful for diagnosis and for monitoring hearing health. In certain environments, speech perception may rely on EHF information, and there is evidence for an association between EHF loss and speech perception difficulties, although this may not be causal: EHF loss may instead be a marker for sub-clinical damage at lower frequencies. If there is a causal relation, then amplification in the EHF range may be beneficial if the technical difficulties can be overcome. EHF audiometry in the clinic presents with no particular difficulty, the biggest obstacle being lack of specialist equipment. Currently, EHF audiometry has limited but increasing clinical application. With the development of international guidelines and standards, it is likely that EHF testing will become widespread in future.
On the angle-dependent vibrational behavior of fiber composite plates and its implications for musical instrument making
Authors: Plath Niko , Linke Simon , Mores Robert
Published: March 2022

Composite materials facilitate the control of specific properties in components while varying the type, angle, and order of individual fiber weaves in the laminate. This possibility of synthesizing material properties has aroused great interest in musical instrument making since the availability of synthetic fiber composites in the 1970s. However, when arranging plies, the combination of weave types and angles can lead to vibroacoustic effects which are unusual for makers used to working with wood. The mechanics behind these effects are described, starting with an outline of the theory of vibrations in thin plates. Further, the consequences of rotating fibers are theoretically derived and, subsequently, examined in a series of measurements on rectangular thin plates as well as assembled violin top plates. From the findings obtained, it can be concluded that the specific characteristics have to be taken into account for a successful use of composite materials in musical instrument making. This paper, therefore, concludes with easy-to-understand recommendations for musical instrument makers when using fiber composites.
Pole Walking Is Faster but Not Cheaper During Steep Uphill Walking
Authors: Giovanelli Nicola , Mari Lara , Patini Asia , Lazzer Stefano
Published: March 2022

Purpose: The aim of this study was to compare pole walking (PW) and walking without poles (W) on a steep uphill mountain path (1.3 km, 433 m of elevation gain) at 2 different intensities: a maximal effort that would simulate a vertical kilometer intensity and a lower intensity (80% of maximal) simulating an ultratrail race. Methods: On the first day, we tested the participants in the laboratory to determine their maximal physiological parameters, respiratory compensation point, and gas exchange threshold. Then, they completed 4 uphill tests along a mountain path on 4 separate days, 2 at their maximum effort (PWmax and Wmax, randomized order) and 2 at 80% of the mean vertical velocity maintained during the first 2 trials (PW80 and W80, randomized order). We collected metabolic data, heart rate, blood lactate concentration, and rating of perceived exertion at the end of each trial. We also collected rating of perceived exertion at every 100 m of elevation gain during PW80 and W80. Results: Participants completed the maximal effort faster with poles versus without poles (18:51 [03:12] vs 19:19 [03:01] in min:s, P = .013, d = 0.08, small). Twelve of the 15 participants (80%) improved their performance when they used poles. During PW80 and W80, none of the physiological or biomechanical parameters were different. Conclusion: In the examined condition, athletes should use poles during steep uphill maximal efforts to obtain the best performance. Conversely, during submaximal effort, the use of poles does not provide advantages in uphill PW.
Multicultural Training and Awareness Among Sport Psychology Practitioners
Authors: Curvey Rena M.G. , White Shannon C. , Murphy Emily A. , Scheadler Travis R. , Englis Myles T. , Phelps Laura L. , Hargons Candice N.
Published: March 2022

Guided by an interpretivist–constructivist paradigm and phenomenological framework, this study explored sport psychology professionals’ lived experiences to better understand their multicultural training and competence within the field of sport psychology. Twelve sport psychology professionals participated in semistructured interviews from March 2020 to May 2020. The following four themes emerged: (a) a call to reform training programs, (b) a shift from multicultural competence to cultural humility, (c) professional and ethical responsibilities of sport psychology practitioners, and (d) reflexive practice and culturally sensitive interventions. Study findings support expanding multicultural training for students of sport psychology graduate programs and suggest that sport psychology professionals have an ethical responsibility to be culturally aware. Further study findings and clinical implications are discussed.
Pharmacokinetics of Temsavir, the Active Moiety of the HIV-1 Attachment Inhibitor Prodrug, Fostemsavir, Coadministered with Cobicistat, Etravirine, Darunavir/Cobicistat, or Darunavir/Ritonavir with or without Etravirine in Healthy Participants
Authors: Moore Katy , Thakkar Nilay , Magee Mindy , Sevinsky Heather , Vakkalagadda Blisse , Lubin Susan , Llamoso Cyril , Ackerman Peter
Published: March 2022

Fostemsavir is a prodrug of temsavir, a first-in-class attachment inhibitor that binds directly to HIV-1 gp120, preventing initial viral attachment and entry into host CD4
+
T cells with demonstrated efficacy in phase 2 and 3. Temsavir is a P-glycoprotein and breast cancer resistance protein (BCRP) substrate; its metabolism is mediated by esterase and CYP3A4 enzymes.
Novel Regimens of Bedaquiline-Pyrazinamide Combined with Moxifloxacin, Rifabutin, Delamanid and/or OPC-167832 in Murine Tuberculosis Models
Authors: Tasneen Rokeya , Garcia Andrew , Converse Paul J. , Zimmerman Matthew D. , Dartois Veronique , Kurbatova Ekaterina , Vernon Andrew A. , Carr Wendy , Stout Jason E. , Dooley Kelly E. , Nuermberger Eric L.
Published: March 2022

A recent landmark trial showed a 4-month regimen of rifapentine, pyrazinamide, moxifloxacin, and isoniazid (PZMH) to be noninferior to the 6-month standard of care. Here, two murine models of tuberculosis were used to test whether novel regimens replacing rifapentine and isoniazid with bedaquiline and another drug would maintain or increase the sterilizing activity of the regimen.
Mycobacterium tuberculosis EspK Has Active but Distinct Roles in the Secretion of EsxA and EspB
Authors: Lim Ze Long , Drever Kylee , Dhar Neeraj , Cole Stewart T. , Chen Jeffrey M.
Published: March 2022

Mycobacterium tuberculosis
uses its ESX-1 system to secrete EsxA and EspB into a host to cause disease. We show that EspK, a protein whose role in the ESX-1 machinery was thought to be nonessential, is needed by
M. tuberculosis
for optimal EsxA and EspB secretion.
Detection of Mixed Populations of Clarithromycin-Susceptible and -Resistant Mycobacterium abscessus Strains
Authors: Shallom Shamira J. , Zelazny Adrian M.
Published: March 2022

Clarithromycin resistance in
Mycobacterium abscessus
subsp.
abscessus
,
massiliense
, and
bolletii
occurs through induction of
erm
(41) or mutations in
rrl
(23S rRNA) genes. Phenotypic detection of clarithromycin resistance is hindered by the need for extended incubation as well as co-occurrence of mixed populations of
M. abscessus
Contrasting Modes of New World Arenavirus Neutralization by Immunization-Elicited Monoclonal Antibodies
Authors: Ng Weng M. , Sahin Mehmet , Krumm Stefanie A. , Seow Jeffrey , Zeltina Antra , Harlos Karl , Paesen Guido C. , Pinschewer Daniel D. , Doores Katie J. , Bowden Thomas A.
Published: March 2022

The GP1 subcomponent of the New World arenavirus GP is a primary target of the neutralizing antibody response, which has been shown to be effective in the prevention and treatment of infection. Here, we characterize the structural basis of the antibody-mediated immune response that arises from immunization of mice against Junín virus and Machupo virus, two rodent-borne zoonotic New World arenaviruses.
Mining the Flavoproteome of Brucella ovis, the Brucellosis Causing Agent in Ovis aries
Authors: Minjárez-Sáenz Martha , Martínez-Júlvez Marta , Yruela Inmaculada , Medina Milagros
Published: March 2022

Some microorganisms depend heavily on flavin-dependent activities, but others maintain them at a minimum. Knowledge about flavoprotein content and functions in different microorganisms will help to identify their metabolic requirements, as well as to benefit either industry or health.
Systemic Homologous Neutralizing Antibodies Are Inadequate for the Evaluation of Vaccine Protective Efficacy against Coinfection by High Virulent PEDV and PRRSV
Authors: Qiu Ming , Li Shubin , Ye Mengxue , Li Jixiang , Sun Zhe , Li Xinshuai , Xu Yulin , Xiao Yanzhao , Li Chen , Feng Binghui , Lin Hong , Zheng Wanglong , Yu Xiuling , Tian Kegong , Zhu Jianzhong , Chen Nanhua
Published: March 2022

Porcine epidemic diarrhea virus (PEDV) and porcine reproductive and respiratory syndrome virus (PRRSV) coinfection occurs commonly and can synergistically reduce feed intake and pig growth. Vaccination is an effective strategy utilized for PED and PRRS control, and systemic homologous neutralizing antibodies (shnAbs) in serum are commonly used for protective efficacy evaluation of PED and PRRS vaccines.
Thin vs. thick-skinned tectonics in the Umbria-Marche fold-and-thrust belt: Contrast or coexistence?
Authors: Barchi Massimiliano Rinaldo , Tavarnelli* Enrico
Published: March 2022

The structural style at depth of the Umbria-Marche fold-and-thrust belt, which occupies the outer province of the Northern Apennines of peninsular Italy, has long been debated and interpreted in terms of thin-skinned or thick-skinned deformation models, respectively. Thin-skinned models predict that the Mesozoic–Tertiary sedimentary cover was detached along Upper Triassic evaporites and translated northeastward along stepped thrust faults above a relatively undeformed basement. On the other hand, thick-skinned models predict the direct involvement of conspicuous basement slices within thrust-related folds. A description of selected examples in the southeastern part of the Umbria-Marche belt reveals that some compressional structures are indeed thin-skinned, their style being controlled by rheological properties of a mechanically heterogeneous stratigraphy containing multiple décollements, whereas other structures are genuinely thick-skinned, their style being dominated by the reverse-reactivation of pre-orogenic normal faults deeply rooted within the basement. Therefore, the contrast of thin- versus thick-skinned structural styles, an issue that has generated a long-lasting debate, is only apparent, since both styles are documented to coexist and to have concurred in controlling the final compressional geometry of the fold-and-thrust belt.
Supplemental Material: Origin of Tibetan post-collisional high-K adakitic granites: Anatexis of intermediate to felsic arc rocks
Authors: Yi Jian-Kang , Zhu Di-Cheng , al. et
Published: March 2022

Supplemental methods, Figures S1‒S5, and Tables S1‒S4.
Severe hyponatraemia in two patients with breast cancer caused by low-dose cyclophosphamide and precipitated by aprepitant
Authors: Parikh Shefali , Pettit Laura , AbdelGadir Huzeifa
Published: March 2022

Two postmenopausal women with breast cancer developed acute confusion and seizures, less than 24 hours after the first cycle of neoadjuvant chemotherapy with fluorouracil, epirubicin and low-dose cyclophosphamide. They were found to have severe, life-threatening hyponatraemia with sodium levels of 113 and 115 mEq/L, respectively. Both women made a full recovery within 24 hours of admission with slow correction of sodium levels. Following investigational workup, the most likely diagnosis was cyclophosphamide-associated syndrome of inappropriate antidiuretic hormone secretion (SIADH). Aprepitant - a commonly used antiemetic and moderate cytochromeP450 3A4 inhibitor was identified as the precipitating factor. Aprepitant was discontinued and both women were successfully re-challenged with full dose cyclophosphamide in an outpatient setting with no subsequent adverse events. This is a typical case of a rare cause of a common medical problem. A systematic approach to diagnosis and treatment of hyponatraemia in an oncology patient requires awareness of toxicities of systemic anticancer agents.
Reversible dementia in the setting of multiple medical comorbidities due to B12 deficiency
Authors: Wong Christopher , Benyaminov Fuad , Block Lauren
Published: March 2022

Vitamin B12 deficiency is a cause of reversible dementia that must be ruled out in the evaluation of neurocognitive decline. We present a case of neurocognitive decline secondary to B12 deficiency where the workup was obscured by multiple competing diagnoses and treatment with empiric B12 supplementation reversed symptoms. Although the pretest probability was low, the morbidity from undiagnosed B12 deficiency is high, warranting a trial of B12 supplementation that resolved the patient’s symptoms.
Visual hallucinations following electroconvulsive therapy for major depressive disorder
Authors: Nix Hayden P , Mather Rookaya , O'Reilly Richard , Vasudev Akshya
Published: March 2022

A female geriatric patient with major depressive disorder, current episode severe, received eight right unilateral electroconvulsive therapy (ECT) treatments over the course of 3 weeks. After her third treatment, she began experiencing brief visual hallucinations, each lasting less than 5 s, consisting of dark to grey coloured, poorly defined geometric shapes and objects. These episodes occurred only during the day with no change in consciousness. With each additional treatment, the episodes increased in frequency, reaching a crescendo of approximately 20 episodes per day. After terminating ECT, the frequency of these episodes decreased and then ceased 6 weeks later. Neuroimaging and ophthalmological investigations discounted a space occupying lesion or vision loss. This case demonstrates a close temporal relationship between ECT and new onset visual hallucinations. Clinicians should be aware of the possibility that elderly depressed patients may develop visual hallucinations during a course of ECT.
Clinical outcomes of penetrating canaloplasty in patients with traumatic angle recession glaucoma: a prospective interventional case series
Authors: Cheng Huanhuan , Ye Wenqing , Zhang Shaodan , Xie Yanqian , Gu Juan , Le Rongrong , Deng Yuxuan , Hu Cheng , Zhao Zhenquan , Ke Zhisheng , Liang Yuanbo
Published: March 2022

Background/aim

To evaluate the clinical outcomes of penetrating canaloplasty in traumatic angle recession glaucoma at 1 year.

Methods

Patients with angle recession glaucoma underwent penetrating canaloplasty, a new Schlemm’s canal-based internal drainage procedure, which creates a direct canal for flow of aqueous humour from the anterior chamber to the ostia of Schlemm’s canal via a window created at the corneal scleral bed without use of antimetabolites. Postoperative intraocular pressure (IOP), number of glaucoma medications, and procedure-related complications were evaluated. Success was defined as an IOP ≤21 mm Hg without (complete) or with (qualified) use of glaucoma medication.

Results

Forty eyes in 40 patients with angle recession glaucoma underwent successful circumferential catheterisation. The mean patient age was 42±13 years. In patients with penetrating canaloplasty that was deemed to be completely successful, the mean IOP decreased from a preoperative value of 37.8±12.3 mm Hg on 3.3±1.2 anti-glaucoma medications to 18.5±6.4 mm Hg on 1.2±1.4 medications, 14.9±4.6 mm Hg on 0.1±0.5 medications, 15.7±5.4 mm Hg on 0.1±0.4 medications and 14.8±3.6 mm Hg on 0.1±0.5 medications at 1, 3, 6 and 12 months postoperatively (p<0.05). Complete success was achieved in 35/40 eyes (87.5%) at 6 months and in 34/38 (89.5%) at 12 months. Hyphema (18/40, 45.0%) and transient IOP elevation (≥30 mm Hg, 9/40, 22.5%) were the most common postoperative complications.

Conclusion

Penetrating canaloplasty significantly reduces IOP and has a high success rate in angle recession glaucoma.

Trial registration number

ChiCTR1900020511.
Overestimating women’s representation in medicine: a survey of medical professionals’ estimates and their(un)willingness to support gender equality initiatives
Authors: Begeny Christopher T , Grossman Rebecca C , Ryan Michelle K
Published: March 2022

Objective

Amidst growing numbers of women in certain areas of medicine (eg, general practice/primary care), yet their continued under-representation in others (eg, surgical specialties), this study examines (1) whether medical professionals mistakenly infer that women are now broadly well represented, overestimating women’struerepresentation in several different areas and roles; and (2) whether this overestimation of women’s representation predicts decreased support for gender equality initiatives in the field, in conjunction with one’s own gender.

Design

Cross-sectional survey.

Setting

UK-based medical field.

Participants

425 UK medical consultants/general practitioners and trainees (ST/CT1+/SHO/Registrar); 47% were female.

Main outcome measures

Estimates of women’s representation in different areas/roles within medicine, examined as a composite estimate and individually; and a multi-item measure of support for gender-based initiatives in medicine.

Results

Medical professionals tended to overestimate women’s true representation in several different areas of medicine (general practice, medical specialties, surgical specialties) and in various roles (consultants/general practitioners, trainees, medical school graduates). Moreover, these erroneous estimates predicted a decreased willingness to support gender-based initiatives, particularly among men in the field: composite overestimation*respondent gender interaction,B=−0.04, 95% CI −0.07 to −0.01, p=0.01. Specifically, while female respondents’ (over)estimates were unrelated to their level of support (B=0.00, 95% CI −0.02 to 0.02, p=0.92), male respondents’ tendency to overestimate the proportion of women in medicine predicted lower support for gender-based initiatives (B=−0.04, 95% CI −0.06 to −0.02, p<0.001).

Conclusions

While some progress has been made in gender representation in the medical field, this research illustrates that there are still barriers to gender equality efforts and identifies who within the field is focally maintaining these barriers. It is those individuals (particularly men) who overestimate thetrueprogress that has been made in women’s representation who are at highest risk of undermining it.
Rapid implementation of an outpatient arthroplasty care pathway: a COVID-19-driven quality improvement initiative
Authors: Peacock Sharon , Wolfstadt Jesse , Peer Miki , Gleicher Yehoshua
Published: March 2022

Background

Hip and knee total joint arthroplasty (TJA) procedures are two of the most common inpatient surgical procedures worldwide. Outpatient TJA has emerged as a feasible option. COVID-19 caused significant constraints on inpatient surgical resources and contributed to a growing surgical backlog. We present a quality improvement (QI) initiative aimed at adding an outpatient TJA pathway to our pre-existing inpatient TJA programme, with the target of performing 25% of our primary TJA as outpatients.

Methods

This was a QI study at a tertiary level arthroplasty centre. To achieve our aim, a patient-centred needs analysis revealed the need to develop patient selection criteria, perform a specific and tailored anaesthetic, provide patient education and conduct virtual care follow-up. Based on these findings, an outpatient TJA intervention bundle was developed and implemented.

Results

After implementing the outpatient pathway, 65 patients were scheduled for outpatient TJA. Fifty-five (84.6%) patients were successfully discharged home on the day of surgery. Successful outpatient TJA accounted for 33.3% of all primary TJAs performed at our intuition throughout the study period. There was excellent adherence to the intervention protocols, with the success hinging on multidisciplinary team and supported QI culture. Thirty-day emergency department visits for inpatient and outpatient TJAs were 8.93% and 6.15%, respectively. No outpatient TJA patients required hospital readmission within 30 days.

Conclusion

Our study demonstrates that implementation of an outpatient TJA pathway in response to inpatient resource constraints during the COVID-19 pandemic is feasible. The findings of this report will be of interest to surgical centres facing surgical backlog and constraints on inpatient resources during and after the pandemic.
Use of e-triggers to identify diagnostic errors in the paediatric ED
Authors: Lam Daniel , Dominguez Fidelity , Leonard Jan , Wiersma Alexandria , Grubenhoff Joseph A
Published: March 2022

Background

Diagnostic errors (DxEs) are an understudied source of patient harm in children rarely captured in current adverse event reporting systems. Applying electronic triggers (e-triggers) to electronic health records shows promise in identifying DxEs but has not been used in the emergency department (ED) setting.

Objectives

To assess the performance of an e-trigger and subsequent manual screening for identifying probable DxEs among children with unplanned admission following a prior ED visit and to compare performance to existing incident reporting systems.

Design/methods

Retrospective single-centre cohort study of children ages 0–22 admitted within 14 days of a previous ED visit between 1 January 2018 and 31 December 2019. Subjects were identified by e-trigger, screened to identify cases where index visit and hospital discharge diagnoses were potentially related but pathophysiologically distinct, and then these screened-in cases were reviewed for DxE using the SaferDx Instrument. Cases of DxE identified by e-trigger were cross-referenced against existing institutional incident reporting systems.

Results

An e-trigger identified 1915 unplanned admissions (7.7% of 24 849 total admissions) with a preceding index visit. 453 (23.7%) were screened in and underwent review using SaferDx. 92 cases were classified as likely DxEs, representing 0.4% of all hospital admissions, 4.8% among those selected by e-trigger and 20.3% among those screened in for review. Half of cases were reviewed by two reviewers using SaferDx with substantial inter-rater reliability (Cohen’s κ=0.65 (95% CI 0.54 to 0.75)). Six (6.5%) cases had been reported elsewhere: two to the hospital’s incident reporting system and five to the ED case review team (one reported to both).

Conclusion

An e-trigger coupled with manual screening enriched a cohort of patients at risk for DxEs. Fewer than 10% of DxEs were identified through existing surveillance systems, suggesting that they miss a large proportion of DxEs. Further study is required to identify specific clinical presentations at risk of DxEs.
Decision-making in palliative care: patient and family caregiver concordance and discordance—systematic review and narrative synthesis
Authors: Mulcahy Symmons Sophie , Ryan Karen , Aoun Samar M , Selman Lucy E , Davies Andrew Neil , Cornally Nicola , Lombard John , McQuilllan Regina , Guerin Suzanne , O'Leary Norma , Connolly Michael , Rabbitte Mary , Mockler David , Foley Geraldine
Published: March 2022

Background

Decision-making in palliative care usually involves both patients and family caregivers. However, how concordance and discordance in decision-making manifest and function between patients and family caregivers in palliative care is not well understood.

Objectives

To identify key factors and/or processes which underpin concordance and/or discordance between patients and family caregivers with respect to their preferences for and decisions about palliative care; and ascertain how patients and family caregivers manage discordance in decision-making in palliative care.

Methods

A systematic review and narrative synthesis of original studies published in full between January 2000 and June 2021 was conducted using the following databases: Embase; Medline; CINAHL; AMED; Web of Science; PsycINFO; PsycARTICLES; and Social Sciences Full Text.

Results

After full-text review, 39 studies were included in the synthesis. Studies focused primarily on end-of-life care and on patient and family caregiver preferences for patient care. We found that discordance between patients and family caregivers in palliative care can manifest in relational conflict and can result from a lack of awareness of and communication about each other’s preferences for care. Patients’ advancing illness and impending death together with open dialogue about future care including advance care planning can foster consensus between patients and family caregivers.

Conclusions

Patients and family caregivers in palliative care can accommodate each other’s preferences for care. Further research is needed to fully understand how patients and family caregivers move towards consensus in the context of advancing illness.
Percutaneous coronary intervention in patients with documented coronary vasospasm during long-term follow-up
Authors: Kim Ju Hyeon , Park Jinoh , Yang Yujin , Lee Sahmin , Kim Dae-Hee , Song Jong-Min , Kang Duk-Hyun , Park Seong-Wook , Park Seung-Jung , Song Jae-Kwan
Published: March 2022

Objective

Although recurring coronary artery spasm (CAS) may lead to the development of fixed atherosclerotic coronary stenosis (FS), the relationship between coronary atherosclerosis and CAS is still speculative. We evaluated the incidence of FS requiring percutaneous coronary intervention (PCI) in patients with documented CAS during long-term follow-up and analysed their clinical features.

Methods

Clinical data of 3556 patients during a median follow-up of 9.4 years after non-invasive ergonovine spasm provocation testing with echocardiographic monitoring of left ventricular wall motion (erg echo) were analysed.

Results

Erg echo documented CAS in 830 (23.3%) patients, who had higher frequencies of coronary risk factors than those without CAS. Patients with documented CAS on erg echo showed significantly lower 10-year overall (90.5% vs 94.2%, p<0.001) and PCI-free (97.4% vs 98.4%, p=0.002) survival rates than those without CAS. Documented CAS was an independent factor associated with later PCI after adjustment by either Cox regression model or Fine-Gray competing risk model. There was no significant difference in baseline clinical characteristics between patients who needed later PCI and those who did not. Among 28 patients who needed later PCI after documentation of CAS, the original CAS and later PCI territory were concordant in 25 (89.3%), while 3 (10.7%) showed discordance.

Conclusions

CAS is a risk factor for the development of FS requiring PCI during long-term follow-up, and warrants physicians’ vigilance and careful follow-up of patients with documented CAS and insignificant stenosis of major epicardial coronary arteries at the time of initial diagnosis.
Invasive coronary physiology in patients with angina and non-obstructive coronary artery disease: a consensus document from the coronary microvascular dysfunction workstream of the British Heart Foundation/National Institute for Health Research Partnership
Authors: Perera Divaka , Berry Colin , Hoole Stephen P , Sinha Aish , Rahman Haseeb , Morris Paul D , Kharbanda Rajesh K , Petraco Ricardo , Channon Keith
Published: March 2022

Nearly half of all patients with angina have non-obstructive coronary artery disease (ANOCA); this is an umbrella term comprising heterogeneous vascular disorders, each with disparate pathophysiology and prognosis. Approximately two-thirds of patients with ANOCA have coronary microvascular disease (CMD). CMD can be secondary to architectural changes within the microcirculation or secondary to vasomotor dysfunction. An inability of the coronary vasculature to augment blood flow in response to heightened myocardial demand is defined as an impaired coronary flow reserve (CFR), which can be measured non-invasively, using imaging, or invasively during cardiac catheterisation. Impaired CFR is associated with myocardial ischaemia and adverse cardiovascular outcomes.

The CMD workstream is part of the cardiovascular partnership between the British Heart Foundation and The National Institute for Health Research in the UK and comprises specialist cardiac centres with expertise in coronary physiology assessment. This document outlines the two main modalities (thermodilution and Doppler techniques) for estimation of coronary flow, vasomotor testing using acetylcholine, and outlines a standard operating procedure that could be considered for adoption by national networks. Accurate and timely disease characterisation of patients with ANOCA will enable clinicians to tailor therapy according to their patients’ coronary physiology. This has been shown to improve patients’ quality of life and may lead to improved cardiovascular outcomes in the long term.
Excessive proliferation and apoptosis of parathyroid cells contribute to primary hyperparathyroidism in rabbit model
Authors: Bi Jing-tao , Bai Rong-jie , Zhan Hui-li , Qian Zhan-hua , Gong Li-hua , Liu Ya-qi , Zheng Zhi-xue , Cai Xuan
Published: March 2022

To explore the molecular pathogenesis of primary hyperparathyroidism (PHPT), we investigated the proliferation and apoptosis of parathyroid cells in a rabbit model of diet-induced PHPT. A total of 120 adult Chinese rabbits were randomly divided into normal diet (Ca:P, 1:0.7) group (control group) or a high-phosphate diet (Ca:P, 1:7) group (experimental group). The thyroid and parathyroid complexes were harvested for 1-month interval from month 1 to month 6. The expression of proliferation markers, including proliferating cell nuclear antigen (PCNA) and cyclin-D1, and B cell lymphoma-2 (Bcl-2), were evaluated by immunohistochemistry in thyroid and parathyroid tissues. Apoptosis was quantified by DNA-fragment terminal labeling. Our results demonstrated that parathyroid cells in the experimental group started proliferating from the end of the 2nd month, the expression of PCNA, Bcl-2, and cyclin-D1 were significantly higher in the PHPT group than those of the control group (p<0.05). Furthermore, the apoptosis index (AI) was positively correlated with the glandular cell count and expression of PCNA in the 6th month in the PHPT group. Overall, our results suggested that excessive proliferation and apoptosis of parathyroid cells may contribute to the pathogenesis of PHPT through PCNA-related, Bcl-2-related, and cyclin-D1-related pathways.
1α,25(OH)2D3reverses exhaustion and enhances antitumor immunity of human cytotoxic T cells
Authors: Li Peng , Zhu Xinhai , Cao Guangchao , Wu Ruan , Li Ke , Yuan Wenhui , Chen Biyun , Sun Guodong , Xia Xichun , Zhang Hua , Wang Xiao , Yin Zhinan , Lu Ligong , Gao Yunfei
Published: March 2022

Background

Epidemiological surveys have revealed that low serum vitamin D level was correlated with increased risk of tumors. Dysfunctional T cells in patients with tumor are characterized as exhausted with high levels of immune checkpoint receptors (ICRs). However, whether the reduced level of vitamin D in patients with cancer correlates with cytotoxic T-cell exhaustion is unknown.

Methods

Periphery blood samples from 172 patients with non-small cell lung cancer (NSCLC) were prospectively collected. Patients with NSCLC received one course of intravenous docetaxel (75 mg/m2) followed by treatment with or without rocaltrol at a dose of 0.5–2.0 µg/day for total of 3 weeks. We performed phenotypical and functional analysis of T-cell through flow cytometry. Vitamin D receptor (VDR) knockout and overexpression CD8+and Vδ2+T cells were constructed using Cas9-gRNA targeted and overexpressing approaches to identify 1α,25(OH)2D3/VDR-mediated transcription regulation for ICRs or antitumor activity in T cells.

Results

We show that serum level of vitamin D is negatively correlated with expression of programmed cell death-1 (PD-1), T-cell immunoreceptor with Ig and ITIM domains (TIGIT), and T-cell immunoglobulin and mucin-domain containing-3 (Tim-3), but positively correlated with CD28 expression on CD8+and Vγ9Vδ2+T cells in patients with NSCLC. 1α,25(OH)2D3, the active form of vitamin D, promotes the nuclear translocation of VDR, which binds to the promoter region ofPdcd1,Tim3, andTigitgenes and inhibits their expression. Besides, 1α,25(OH)2D3pretreatment also promotes the methylation of CpG island in the promoter region of thePdcd1gene and increases H3K27 acetylation at the promoter region of theCd28gene, which leads to surface PD-1 downregulation and CD28 upregulation, respectively. We further reveal that VDR-mediated Ca2+influx enhanced expression of Th1 cytokines via T-cell receptor activation. Functionally, 1α,25(OH)2D3pretreated CD8+T cells or Vγ9Vδ2+T cells showed increased Th1 cytokine production and enhanced antitumor immunity. Finally, oral 1α,25(OH)2D3could also decrease expression of PD-1, Tim-3, TIGIT and increase expression of CD28, resulting in cytokine production (associated with antitumor immunity) by cytotoxic T cells of patients with NSCLC.

Conclusions

Our findings uncover the pleiotropic effects of 1α,25(OH)2D3in rescuing the exhausted phenotype of human cytotoxic T cells in patients with tumor and in promoting their antitumor immunity.

Trial registration number

ChiCTR2100051135.
Sparing the doctor’s blushes: the use of sexually explicit films for the purpose of Sexual Attitude Reassessment (SAR) in the training of medical practitioners in Britain during the 1970s
Authors: Irwin Robert
Published: March 2022

The general reluctance of medical practitioners in postwar Britain to ‘speak of sex’ during healthcare consultations increasingly became a matter of professional concern in the wake of legal reforms and social changes during the 1960s affecting sexual expression and reproductive health, and a growing optimism in the early 1970s concerning the treatment of sexual difficulties. In the mid-1970s, largely as a result of the work of Dr Elizabeth Stanley, Sexual Attitude Reassessment (SAR) seminars were introduced from the USA into some medical schools in Britain, usually as a part of courses that were intended to help students develop the attitudes, knowledge and skills needed to facilitate the discussion of patients’ sexual concerns and to treat ‘simple’ sexual problems. SAR seminars entailed the showing of sexually explicit films as a stimulus for exploring, in small discussion groups, the sexual attitudes and beliefs of students, and the potential impact of these on future professional practice. Drawing on publications by Dr Elizabeth Stanley as well as archival materials, this article examines the aims of SAR seminars, the rationale provided for their inclusion in the undergraduate medical curriculum, and the ‘permission-giving’, educative approach to sexual counselling that SAR seminars supported. It also explores some of the barriers to the more widespread use of such seminars in medical education in Britain at this time. The behaviourally informed ‘permission-giving’ approach to sexual counselling promoted by Stanley and others is also considered alongside the more psychoanalytically informed ‘interpretative’ form of sexual counselling provided by some Family Planning Association doctors from the late 1950s onwards. This comparative analysis reveals contrasting perceptions concerning the role of medical practitioners’ emotions in sexual counselling and elucidates some of the reasons for the fragmented and limited development of this aspect of medical practice in Britain.
Evaluation of Sine Spin flat detector CT imaging compared with multidetector CT
Authors: Petroulia Valentina D , Kaesmacher Johannes , Piechowiak Eike I , Dobrocky Tomas , Pilgram-Pastor Sara M , Gralla Jan , Wagner Franca , Mordasini Pasquale
Published: March 2022

Background

Flat detector computed tomography (FDCT) is widely used for periprocedural imaging in the angiography suite. Sine Spin FDCT (SFDCT) is the latest generation of cone beam CT using a double oblique trajectory for image acquisition to reduce artefacts and improve soft tissue brain imaging. This study compared the effective dose, image quality and diagnostic performance of the latest generation of SFDCT with multidetector CT (MDCT).

Methods

An anthropomorphic phantom equipped with MOSFET detectors was used to measure the effective dose of the new 7sDCT Sine Spin protocol on a latest generation biplane angiographic C-arm system. Diagnostic performance was evaluated on periprocedurally acquired SFDCT for depiction of anatomical details, detection of hemorrhage, and ischemia and was compared with preprocedurally acquired MDCT. Inter- and intra-rater correlation as well as sensitivity and specificity were calculated.

Results

Both modalities showed equal diagnostic performance in the supratentorial ventricular system. SFDCT provided inferior image quality in grey-white matter differentiation and infratentorial structures. Intraventricular, subarachnoid and parenchymal hemorrhages were diagnosed with a sensitivity of 83.3%, 84.2% and 75% and a specificity of 97.3%, 80.0% and 100%, respectively; early ischemic lesions with a sensitivity of 73.3% and specificity 94.7%. The effective dose measured for the 7sDCT Sine Spin protocol was 2 mSv.

Conclusions

Our findings confirm the high diagnostic sensitivity and specificity of SFDCT in detecting intracranial hemorrhage and early ischemic lesions. The delineation of grey-white matter differentiation and infratentorial structures remains a limiting factor. In comparison to previous studies, the new 7sDCT Sine Spin protocol showed a lower effective dose.