bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bilateral regional extracranial blood flow regulation to hypoxia and unilateral duplex ultrasound measurement error
Authors: Friend Alexander T. , Rogan Matthew. , Rossetti Gabriella M. K. , Lawley Justin S. , Mullins Paul G. , Sandoo Aamer , Macdonald Jamie H. , Oliver Samuel J. 
Published: April 2021

New Findings
What is the central question of this study?
Is blood flow regulation to hypoxia different between the internal carotid arteries (ICAs) and vertebral arteries (VAs), and what is the measurement error in unilateral extracranial artery assessments compared to bilateral?
What is the main finding and its importance?
ICA and VA blood flow regulation to hypoxia is comparable when factoring for vessel type and vessel side. Compared to bilateral assessment, vessels assessed unilaterally had individual measurement errors of up to 37%. Assessing the vessel with the larger resting blood flow, not the left or right vessel, reduces unilateral measurement error.
AbstractWhether blood flow regulation to hypoxia is similar between left and right internal carotid arteries (ICAs) and vertebral arteries (VAs) is unclear. Extracranial blood flow is regularly calculated by doubling a unilateral assessment; however, lateral artery differences may lead to measurement error. This study aimed to determine extracranial blood flow regulation to hypoxia when factoring for vessel type (ICAs or VAs) and vessel side (left or right) effects, and to investigate unilateral assessment measurement error compared to bilateral assessment. In a repeated‐measures crossover design, extracranial arteries of 44 participants were assessed bilaterally by duplex ultrasound during 90 min of normoxic and poikilocapnic hypoxic (12.0% fraction of inspired oxygen) conditions. Linear mixed model analyses revealed no Condition × Vessel Type × Vessel Side interaction for blood flow, vessel diameter and flow velocity (all P > 0.05) indicating left and right ICA and VA blood flow regulation to hypoxia was similar. Bilateral hypoxic reactivity was comparable (ICAs, 1.4 (1.0) vs. VAs, 1.7 (1.1) Δ%·Δ−1; P = 0.12). Compared to bilateral assessment, unilateral mean measurement error of the relative blood flow response to hypoxia was up to 5%, but individual errors reached 37% and were greatest in ICAs and VAs with the smaller resting blood flow due to a ratio‐scaling problem. In conclusion, left and right ICA and VA regulation to hypoxia is comparable when factoring for vessel type and vessel side. Assessing the ICA and VA vessels with the larger resting blood flow, not the left or right vessel, reduces unilateral measurement error.
Association between cortical thickness and distinct vascular cognitive impairment and dementia in patients with white matter lesions
Authors: Liu Yafei , Hu Anming , Chen Luyao , Li Bo , Zhang Minjian , Xi Pengcheng , Yang Qinghu , Tang Rongyu , Huang Qiang , He Jiping , Lang Yiran , Zhang Yumei 
Published: April 2021

New Findings

What is the central question of this study?
White matter lesions (WMLs) are a brain disease characterized by altered brain structural and functional connectivity, but findings have shown an inconsistent pattern: are there distinct cortical thickness changes in patients with WMLs subtypes?

What is the main finding and its importance?
Patients with WMLs with non‐dementia vascular cognitive impairment and WMLs with vascular dementia showed distinct pathophysiology in cortical thickness. These neural correlates of WMLs should be considered in future treatment.

AbstractThe effect of cortical thickness on white matter lesions (WMLs) in patients with distinct vascular cognitive impairments is relatively unknown. This study investigated the correlation between cortical thickness and vascular cognitive manifestations. WML patients and healthy controls from Beijing Tiantan Hospital between 2014 and 2018 were included. The patients were further divided into two subgroups, namely WMLs with non‐dementia vascular cognitive impairment (WML‐VCIND) and WMLs with vascular dementia (WML‐VaD) according to the Clinical Dementia Rating (CDR) scale and the Beijing version of the Montreal Cognitive Assessment (MoCA). Changes in cortical thickness were calculated using FreeSurfer. Pearson's correlation analysis was performed to explore the relationship between cognitive manifestations and cortical thickness in WML patients. Forty‐five WML patients and 23 healthy controls were recruited. The WML group exhibited significant difference in cortical thickness compared to the control group. Significantly decreased cortical thickness in the middle and superior frontal gyri, middle temporal gyrus, angular gyrus and insula was found in the WML‐VaD versus WML‐VCIND subgroup. Cortical thickness deficits of the left caudal middle frontal gyrus (r = 0.451, P = 0.002), left rostral middle frontal gyrus (r = 0.514, P < 0.001), left superior frontal gyrus (r = 0.410, P = 0.006), right middle temporal gyrus (r = 0.440, P = 0.003), right pars triangularis (r = 0.462, P = 0.002), right superior frontal gyrus (r = 0.434, P = 0.004) and right insula (r = 0.499, P = 0.001) were positively correlated with the MoCA score in WML patients. The specific pattern of cortical thickness deficits in the WML‐VaD subgroup revealed the pathophysiology of WMLs, which should be considered in future treatment of WMLs.
The effect of heat therapy on blood pressure and peripheral vascular function: A systematic review and meta‐analysis
Authors: Pizzey Faith K. , Smith Emily C. , Ruediger Stefanie L. , Keating Shelley E. , Askew Christopher D. , Coombes Jeff S. , Bailey Tom G. 
Published: April 2021

New FindingsWhat is the topic of this review?We have conducted a systematic review and meta‐analysis on the current evidence for the effect of heat therapy on blood pressure and vascular function.What advances does it highlight?We found that heat therapy reduced mean arterial, systolic and diastolic blood pressure. We also observed that heat therapy improved vascular function, as assessed via brachial artery flow‐mediated dilatation. Our results suggest that heat therapy is a promising therapeutic tool that should be optimized further, via mode and dose, for the prevention and treatment of cardiovascular disease risk factors.AbstractLifelong sauna exposure is associated with reduced cardiovascular disease risk. Recent studies have investigated the effect of heat therapy on markers of cardiovascular health. We aimed to conduct a systematic review with meta‐analysis to determine the effects of heat therapy on blood pressure and indices of vascular function in healthy and clinical populations. Four databases were searched up to September 2020 for studies investigating heat therapy on outcomes including blood pressure and vascular function. Grading of Recommendations, Assessment, Development and Evaluations (GRADE) was used to assess the certainty of evidence. A total of 4522 titles were screened, and 15 studies were included. Healthy and clinical populations were included. Heat exposure was for 30–90 min, over 10–36 sessions. Compared with control conditions, heat therapy reduced mean arterial pressure [n = 4 studies; mean difference (MD): −5.86 mmHg, 95% confidence interval (CI): −8.63, −3.10;P < 0.0001], systolic blood pressure (n = 10; MD: −3.94 mmHg, 95% CI: −7.22, −0.67;P = 0.02) and diastolic blood pressure (n = 9; MD: −3.88 mmHg, 95% CI: −6.13, −1.63;P = 0.0007) and improved flow‐mediated dilatation (n = 5; MD: 1.95%, 95% CI: 0.14, 3.76;P = 0.03). Resting heart rate was unchanged (n = 10; MD: −1.25 beats/min; 95% CI: −3.20, 0.70;P = 0.21). Early evidence also suggests benefits for arterial stiffness and cutaneous microvascular function. The certainty of evidence was moderate for the effect of heat therapy on systolic and diastolic blood pressure and heart rate and low for the effect of heat therapy on mean arterial pressure and flow‐mediated dilatation. Heat therapy is an effective therapeutic tool to reduce blood pressure and improve macrovascular function. Future research should aim to optimize heat therapy, including the mode and dose, for the prevention and management of cardiovascular disease.
Analysis of an Integrated Thermal Energy System for Applications in Cold Regions
Authors: Addo-Binney Bismark , Besada Wahid , Agelin-Chaab Martin 
Published: April 2021

Abstract
This paper performed analyses on a proposed direct wind-powered heat pump integrated with a pond which serves as an evaporator for space heating in cold regions. The analysis was conducted using environmental data for selected locations in Canada and the engineering equation solver (EES). Three different pairings of heat pumps and wind turbines were studied (a wind-powered heat pump with a pond as an evaporator, wind-powered heat pump without a pond, and an electricity-powered heat pump (EPHP)). Energy and exergy analyses were performed on the systems. The novelty in the present study is in the use of a wind turbine to directly power the heat pump and using a pond as the evaporator. The results show that the proposed system has the highest coefficient of performance (COP) compared with the others. The average coefficient of performance for the selected locations is 2.7, which is at least 67% better than the others. Similarly, the overall exergy for the proposed system is 16.9%, which is at least 40% better than the others. The average heating capacity of the selected locations for the proposed system is 4.5 kW, which is from 29% to 300% better than the others. Additionally, the sustainability index (SI) for the proposed system is the highest for the proposed system. The results have shown that the proposed system has superior overall performance for space heating in cold regions.
On the Supercritical Carbon Dioxide Recompression Cycle
Authors: You Dongchuan , Metghalchi Hameed 
Published: April 2021

Abstract
Supercritical carbon dioxide (sCO2) Brayton cycle has been studied in recent years, and its high efficiency and environmental safety have been investigated. One of the most promising sCO2 designs is the Recompression cycle described in the Introduction of the paper. In this paper, an effort has been made to optimize the operation of a recompression cycle by performing parametric analyses on pressure ratio, split fraction, and maximum temperature. The effects of varying these parameters on thermal efficiency as well as exergetic efficiency have been determined.
Sea Spray Icing: The Physical Process and Review of Prediction Models and Winterization Techniques
Authors: Deshpande Sujay , Sæterdal Ane , Sundsbø Per-Arne 
Published: April 2021

Abstract
Ice accretion on marine vessels and offshore structures is a severe hazard in the Polar regions. There are increasing activities related to oil and gas exploration, tourism, cargo transport, and fishing in the Arctic. Ice accretion can cause vessel instability, excess load on marine structures, and represents a safety risk for outdoor working environment and operations. Freezing sea spray is the main contributor to marine icing. For safe operations in cold climates, it is essential to have verified models for the prediction of icing. Sea spray icing forecast models have improved. Empirical and theoretical models providing icing rates based may be useful as guidelines. For predicting the distribution of icing on a surface at the design stage, computational fluid dynamics has to be applied along with a freezing module. State-of-the-art models for numerical simulation of sea spray icing are still not fully capable of modeling complex ship-sea-wind interactions with spray generation and impact of shipped water. Existing models include a good understanding of spray flow effects and freezing. Further development should focus on developing models for dynamic ship-sea-wind interactions, in particular including spray generation, effects of shipped water, and distribution of icing on the vessel surface. More experimental and full-scale data are needed for the development and verification of new and improved models. Models that estimate ice distribution may improve the winterization design process and reduce the effort required for de-icing. Improved methods for de-icing and anti-icing will reduce the impact of sea spray icing and increase safety for marine operations in cold waters.
A Review of Ice Protection Techniques for Structures in the Arctic and Offshore Harsh Environments
Authors: Shi Kewei , Duan Xili 
Published: April 2021

Abstract
Icing can jeopardize local infrastructure, hinder field operation, destroy vessel superstructures, and threaten life and property safety in the Arctic and other cold offshore and marine environments. Research on ice protection (both anti-icing and de-icing) technologies is critical to equipment, structures, and personnel in these environments. This review systematically evaluates a wide range of ice protection techniques divided into three main categories, i.e., active, passive, and hybrid ice protection techniques. Active anti-icing/de-icing technologies include mechanical, thermal, or chemical methods, requiring an additional energy source to prevent ice formation or remove accumulated ice from the target surfaces. Passive anti-icing/de-icing techniques can prevent ice accumulation or reduce ice adhesion without external energy sources; they create and maintain the icephobic properties of the target surfaces. Excessive energy consumption is a major technical limitation of active ice protection technologies. On the other hand, it is challenging for any passive technology to meet the long-term ice protection requirements in the Arctic or different cold offshore/marine environments. A combination of two or more active and passive ice protection methods, i.e., a hybrid approach, seems promising and can be applied in various situations according to the specific requirements of different vessels, offshore structures, and equipment.
The Role of Surface Topography and Normal Load in the Initiation of Ratchetting-Peak Friction, Seizure, Scuffing, and Elastic Shakedown
Authors: Edachery Vimal , Swamybabu V. , Gurupatham Anand , Paramasamy Manikandan , Kailas Satish V. 
Published: April 2021

Abstract
Surface topography is a critical parameter that can influence friction and wear in engineering applications. In this study, the influence of surface topography directionality on seizure and scuffing initiation during tribological interactions is explored. Hence, unidirectional sliding wear experiments were carried out in immersed lubrication conditions for various normal loads. The tribological interactions were studied using EN31-60 HRC flats and SAE52100-60 HRC pins in a sphere on flat configuration. The results show that, in some cases, the sliding interactions in the initial cycles lead to a high friction coefficient of up to ∼0.68 in lubricated conditions, which was termed as “peak friction”, and this was accompanied by scuffing. The existence of peak friction was found to be dependent on surface topography directionality, especially when the directionality in topography was parallel to the sliding direction. Continuous ratchetting was found to be the cause of peak friction, which was accompanied by seizure and scuffing. When the topography directionality was perpendicular or independent of the sliding direction, elastic shakedown occurred at earlier cycles and prevented peak friction initiation and scuffing and also facilitated for higher steady-state friction values.
Bowen–York model solution redux
Authors: Altas Emel , Tekin Bayram 
Published: April 2021

AbstractInitial value problem in general relativity is often solved numerically; with only a few exceptions one of which is the “model” solution of Bowen and York where an analytical form of the solution is available. The solution describes a dynamical, time-asymmetric, gravitating system with mass and linear momentum. Here we revisit this solution and correct an error which turns out to be important for identifying the energy-content of the solution. Depending on the linear momentum, the ratio of the non-stationary part of the initial energy to the total ADM energy takes values between [0, 0.592). This non-stationary part is expected to be turned into gravitational waves during the evolution of the system to possibly settle down to a black hole with mass and linear momentum. In the ultra-relativistic case (the high momentum limit), the maximum amount of gravitational wave energy is 59.2% of the total ADM energy. We also give a detailed account of the general solution of the Hamiltonian constraint.
A Proximal Bundle Method with Exact Penalty Technique and Bundle Modification Strategy for Nonconvex Nonsmooth Constrained Optimization
Authors: Wang Xiaoliang , Pang Liping , Wu Qi 
Published: April 2021

The bundle modification strategy for the convex unconstrained problems was proposed by Alexey et al. [[2007] European Journal of Operation Research, 180(1), 38–47.] whose most interesting feature was the reduction of the calls for the quadratic programming solver. In this paper, we extend the bundle modification strategy to a class of nonconvex nonsmooth constraint problems. Concretely, we adopt the convexification technique to the objective function and constraint function, take the penalty strategy to transfer the modified model into an unconstrained optimization and focus on the unconstrained problem with proximal bundle method and the bundle modification strategies. The global convergence of the corresponding algorithm is proved. The primal numerical results show that the proposed algorithms are promising and effective.
Does additional weekend and holiday physiotherapy benefit geriatric patients with hip fracture? — A case-historical control study
Authors: Mo Dennis Kim Chung , Lau Ken Kin Ming , Fung Donna Mei Yee , Ma Bosco Hon Ming , Lau Titanic Fuk On , Law Sheung Wai 
Published: April 2021

Objective: To evaluate the new service model of additional weekend and holiday physiotherapy (PT) by comparing functional outcomes and hospital length of stay between a group of geriatric patients with hip fracture receiving daily PT training and a group of geriatric patients with hip fracture receiving weekdays PT training. Methods: A retrospective case-historical control chart review was conducted and a total of 355 patients were identified. Between-group comparisons were done on functional outcomes including Modified Functional Ambulation Classification (MFAC), Elderly Mobility Scale (EMS), Modified Barthel Index (MBI) and process outcome in terms of length of stay (LOS) in hospitals. Results: With similar characteristics, patients who received weekend and holiday PT training had a significant higher percentage of MFAC Category III and a significant lower percentage of MFAC Category II ([Formula: see text]) and significant higher MBI scores ([Formula: see text] deviation, median; Study group: [Formula: see text] points, 51 points; Control group: [Formula: see text] points, 43 points; [Formula: see text]) upon admission to rehabilitation hospital. A similar trend in EMS scores (Study group: [Formula: see text] points, 7 points; Control group: [Formula: see text] points, 6 points; [Formula: see text]) and MBI scores (Study group: [Formula: see text] points, 68 points; Control group: [Formula: see text] points, 64 points; [Formula: see text]) were observed upon discharge from the rehabilitation hospital. The average LOS in acute hospitals remained static (Study group: [Formula: see text] days, 7 days; Control group: [Formula: see text] days, 6 days; [Formula: see text]). The average LOS in rehabilitation hospital (Study group: [Formula: see text] days, 20 days; Control group: [Formula: see text] days, 23 days; [Formula: see text]) and total in-patient LOS (Study group: [Formula: see text] days, 26 days; Control group: [Formula: see text] days, 28 days; [Formula: see text]) were significantly reduced. A higher percentage of days having PT training during hospitalization in rehabilitation hospital was shown with the implementation of new service (Study group: 89.1%; Control group: 65.9%, [Formula: see text]). Conclusion: Additional weekend and holiday PT training in post-operative acute and rehabilitation hospitalization benefits geriatric patients with hip fracture in terms of improved training efficiency, where hospital LOS was shortened with more PT sessions, without any significant impacts on functional outcome.
Limiting potential COVID-19 contagion in squatting public toilets
Authors: Pan Li , Chen Shuang-Lan , Guo Yi-Sha , Du Yu-Xiang , Wu Xiao-Di , Jones Alice Y. M. , Han Jia 
Published: April 2021

Background: Since the outbreak of the SARS-CoV-2 virus in December 2019, the COVID-19 pandemic continues to threaten global stability. Transmission of SARS-CoV-2 is mostly by respiratory droplets and direct contact but viral RNA fragments have also been detected in the faecal waste of patients with COVID-19. Cleanliness and effective sanitation of public toilets is a concern, as flushing the toilet is potentially an aerosol generating procedure. When the toilets are of the squatting type and without a cover, there exists a risk of viral contamination through the splashing of toilet water and aerosol generation. Objective: This study aims to determine whether the cleanliness of public toilets was a concern to the general population during the COVID-19 pandemic, and whether a squatting toilet was preferred to a seated design. Methods: A questionnaire was designed and posted on “WeChat” contact groups of the investigators. Results: The survey showed that 91% of participants preferred squatting toilets, but that 72% were apprehensive of personal contamination when using public toilets. Over 63% of the respondents had encountered an incidence of water splash and would prefer public toilets to be covered during flushing and 83% of these respondents preferred a foot-controlled device. Conclusion: This survey suggests that consideration should be given to the installation of a simple foot-controlled device to cover public squatting toilets to help restrict potential COVID-19 contamination and to meet hygienic expectations of the public.
Peer Assessment in Medical Student Education: A Study of Feasibility, Benefit, and Worth
Authors: DuCoin Christopher , Zuercher Hannah , McChesney Shannon L. , Korndorffer James R. 
Published: April 2021

Background Direct experience with medical procedures is an important component of medical school training, yet opportunities for medical students have dwindled for various reasons. To offset this, simulated procedures are being integrated into training. However, this comes with additional time commitments required of teaching surgeons regarding assessment of simulation. A solution to this could be peer assessment. We hypothesize that there will be no significant difference between peer assessment when compared to that of a teaching surgeon. Methods Third-year medical students were shown 3 simulated procedures by teaching surgeon and provided a grading rubric. Student performances were independently graded by peer assessment and by teaching surgeons. All peer assessment grades and surgeon grades were compared. Results Four hundred fifty-nine medical students completed the simulation procedures. Comparisons between the teaching surgeons and peer assessment evaluations demonstrated a 99% interobserver agreement for pass-fail designation and 98% agreement for individual data points (kappa = .78). Survey results demonstrated a significant increase in confidence in performing the tested items and comfort with peer assessment. Discussion This analysis demonstrates that the inclusion of peer assessment within medical school is highly comparable to teaching surgeon assessments.