bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of Relative Endwall Motion Effects in a Compressor Cascade Through Direct Numerical Simulations
Authors: Ventosa-Molina Jordi , Lange Martin , Mailach Ronald , Fröhlich Jochen
Published: November 2020

Linear cascades are commonly used as surrogate geometries when performing fundamental studies of turbomachinery blading. Several effects are not accounted for in linear cascades, such as the relative motion between blade and endwall. In this study, three different relative endwall velocities are analyzed. The effect of the relative motion between endwall and blade in a linear compressor cascade is studied through direct numerical simulations. Results show a significant change in the secondary flow structure within the passage. Most notably, the tip leakage vortex is displaced away from the blade. Still, the blade spanwise range affected by the secondary flow field is similar to the case without relative endwall motion. At the outlet plane, a stratification of the total pressure losses and the exit flow angle is found, which overshadows any blade wake effects near the endwall.
Numerical Study on Flow Field in a Peripheral Ported Rotary Engine Under the Action of Apex Seal Leakage
Authors: Fan Baowei , Wang Yuanguang , Pan Jianfeng , Zhang Yaoyuan , Zeng Yonghao
Published: November 2020

Apex seal leakage is one of the main defects restricting the performance improvement of rotary engines. The aim of this study is to study the airflow movement in a peripheral ported rotary engine under the action of apex seal leakage. For this purpose, a three-dimensional (3D) dynamic calculation model considering apex seal leakage was first established and verified by particle image velocimetry data. Furthermore, based on the established 3D model, the flow field in the combustion chamber under the four apex seal leakage gaps (0.02, 0.04, 0.06, and 0.08 mms) and the three engine revolution speeds (2000, 3500, and 5000 RPMs) was calculated. By comparing with the flow field under the condition without leakage, the influences of the existence of apex seal leakage on the velocity field, the turbulent kinetic energy, and the volumetric efficiency in the combustion chamber were investigated. Thereinto, the influences of the existence of apex seal leakage on the velocity field is that at the intake stroke, a vortex formed in the middle of the combustion chamber under the condition without apex seal leakage, was intensified by the apex seal leakage action. At the compression stroke, irrespective of the condition with or without apex seal leakage, all vortexes in the combustion chamber are gradually broken into a unidirectional flow. However, there is an obvious “leakage flow area” at the end of combustion chamber due to the existence of apex seal leakage.
A Detailed Description of Flow-Deck Interaction in Consecutive Green Water Events
Authors: Hernández-Fontes Jassiel V. , Mendoza Edgar , Hernández Irving D. , Silva Rodolfo
Published: November 2020

This paper gives a detailed description of the main hydrodynamic characteristics of different types of green water events occurring on a fixed structure in a series of experiments. High-speed video, at 250 fps, was used to capture the flow details from regular waves produced inside a wave flume. The green water events were classified according to their type and the results of the evaluation from the apparent and effective interaction features. The air cavities in the plunging-dam-break (PDB)-type events were almost spherical for longer waves. PDB with large, elliptical cavities, and hammer-fist (HF)-type events occurred with steeper waves. The highest wave front and bow run-up velocities were found in PDB and HF events, respectively. The size of the cavities in PDB events increases and becomes more elliptical for higher bow run-up velocities. The results of these experiments show that not all events can be treated in the same way as the dam-break (DB)-type events when designing structures or implementing models, as not all interactions with the deck happen when the shipping water crosses the bow edge.
Analysis of Gas Production in Overcharged Lithium Battery by X-Ray Computed Tomography
Authors: Zhang Xiaofan , Li Lifu , Xu Wei
Published: November 2020

Overcharge is one of the main factors that lead to thermal runaway of lithium batteries. However, there is no research on the quantitative relationship between overcharged state and gas production, so as to effectively monitor the safe state of the battery and avoid thermal runaway. In this paper, X-ray computed tomography (CT) is proposed to explore the overcharge battery. The internal structure changes of bulge deformation and electrode separation is observed from tomographic images of two different cross-sectional directions. The relationship between gas production and overcharge state of charge (SOC) is quantitatively analyzed. As overcharge SOC increases, gas production increases exponentially. Gas distribution is analyzed by density distribution feature (DDF) vector. The gas production is mainly distributed in the middle of the overcharge batteries. It is envisaged that these techniques can be used to better understand the overcharge of battery nondestructively, visually and effectively, then will lead to avoid the occurrence of thermal runaway.
Stress-Blended Eddy Simulation/Flamelet Generated Manifold Simulation of Film-Cooled Surface Heat Transfer and Near-Wall Reaction
Authors: Xia Yu , Sharkey Patrick , Orsino Stefano , Kuron Mike , Menter Florian , Verma Ishan , Malecki Robert , Sen Baris
Published: November 2020

Accurate numerical prediction of surface heat transfer in the presence of film cooling within aero-engine sub-components, such as blade effusion holes and combustor liners, has long been a goal of the aero-engine industry. It requires accurate simulation of the turbulent mixing and reaction processes between freestream and the cooling flow. In this study, the stress-blended eddy simulation (SBES) turbulence model is used together with the flamelet generated manifold (FGM) combustion model to calculate the surface heat flux upstream and downstream of an effusion cooling hole. The SBES model employs a blending function to automatically switch between Reynolds-averaged Navier–Stokes (RANS) and large eddy simulation (LES) based on the local flow features, and thus significantly reduces the computational cost compared to a full LES simulation. All simulations are run using ansys fluent®, a commercial finite-volume computational fluid dynamics (CFD) solver. The test case corresponds to an experimental rig run at Massachusetts Institute of Technology (MIT), which is essentially a flat plate brushed by a uniform freestream of argon with ethylene seeded inside, and is cooled by either a reacting air or a non-reacting nitrogen jet inclined at 35 deg to the freestream. Calculations are performed for both reacting and non-reacting jet cooling cases across a range of jet-to-stream blowing ratios and compared with the experimental data. The effects of mesh resolution are also investigated. Calculations are also performed across a range of Damköhler number (i.e., flow to chemical time ratio) from zero to 30, with unity blowing ratio, and the differences in the maximum surface heat flux magnitude in the reacting and non-reacting cases at a specific location downstream of the hole are investigated. Results from these analyses show good correlation with the experimental heat flux data upstream and downstream of the cooling hole, including the heat flux augmentation due to local reaction. Results from the Damköhler number sweep also show a good match with the experimental data across the range investigated.
Effect of Stretching Protocols on Glenohumeral-Joint Muscle Activation in Elite Table Tennis Players
Authors: Kazemi Omid , Letafatkar Amir , Marchetti Paulo H.
Published: November 2020

Context: Several studies report static-stretch-induced deficits and dynamic-stretch performance improvement after intervention. Purpose: To investigate the muscle activation of the forehand and backhand in table tennis players after experiencing static- and dynamic-stretching protocols. Methods: A total of 24 elite male table tennis players (age 22.7 [3.46] y, height 1.78 [0.03] m) were tested before and 0, 10, 20, and 30 min after the 3 conditions (dynamic stretch, static stretch, and no stretch). The MEGA ME6000 (Mega Electronics, Kuopio, Finland) was used to capture the surface EMG data of the anterior deltoid, middle deltoid, posterior deltoid, biceps, and triceps muscles. Muscle activation data of the pretest were compared with posttest 0, 10, 20, and 30 min. These data were also compared between 3 different conditions (dynamic stretch, static stretch, and no stretch). Results: A 2-way repeated-measures analysis of variance indicated significant differences in the forehand and backhand, and Bonferroni test as a post hoc comparison revealed significant differences between the pretest and posttests in several muscles (P < .05). Furthermore, there were significant differences in the posttest between the 3 conditions (P < .05). Conclusions: In general, there was a short-term effect of static- and dynamic-stretching protocols on glenohumeral-joint muscle activation in elite table tennis players. The static and dynamic stretching presented a decrease and increase, respectively, in muscle activation up to 30 min after stretching. In conclusion, the additive and subtractive effects of dynamic- and static-stretching protocols on muscle activation seem to persist after 30 min.
The Temporal Relations of Adolescents’ Basic Need Satisfaction in Physical Education and Global Self-Worth
Authors: Erdvik Irina Burchard , Haugen Tommy , Ivarsson Andreas , Säfvenbom Reidar
Published: November 2020

This study investigated the temporal relations of adolescents’ basic need satisfaction in physical education (PE) and global self-worth in a sample of 3,398 lower and upper secondary school students (49% boys, 51% girls, average age T1 = 15.00,SD = 1.79). Four models and competing hypotheses were tested, and the model with bidirectional paths specified showed the best fit to the data. The bidirectional effect estimates suggest not only that basic need satisfaction in PE predicts global self-worth development but also that adolescents’ perceptions of global self-worth predict the degree to which they experience basic need satisfaction in PE. Findings could suggest that students with low global self-worth are less sensitive to basic need support in PE. These students may need personally tailored need-supportive initiatives in order to develop basic need satisfaction in PE and, thus, global self-worth through PE.
A human cell atlas of fetal chromatin accessibility
Authors: Domcke Silvia , Hill Andrew J. , Daza Riza M. , Cao Junyue , O’Day Diana R. , Pliner Hannah A. , Aldinger Kimberly A. , Pokholok Dmitry , Zhang Fan , Milbank Jennifer H. , Zager Michael A. , Glass Ian A. , Steemers Frank J. , Doherty Dan , Trapnell Cole , Cusanovich Darren A. , Shendure Jay
Published: November 2020

The genomics of human development

Understanding the trajectory of a developing human requires an understanding of how genes are regulated and expressed. Two papers now present a pooled approach using three levels of combinatorial indexing to examine the single-cell gene expression and chromatin landscapes from 15 organs in fetal samples. Cao
et al.
focus on measurements of RNA in broadly distributed cell types and provide insights into organ specificity. Domcke
et al.
examined the chromatin accessibility of cells from these organs and identify the regulatory elements that regulate gene expression. Together, these analyses generate comprehensive atlases of early human development.

Science
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, p.
eaba7612
A human cell atlas of fetal gene expression
Authors: Cao Junyue , O’Day Diana R. , Pliner Hannah A. , Kingsley Paul D. , Deng Mei , Daza Riza M. , Zager Michael A. , Aldinger Kimberly A. , Blecher-Gonen Ronnie , Zhang Fan , Spielmann Malte , Palis James , Doherty Dan , Steemers Frank J. , Glass Ian A. , Trapnell Cole , Shendure Jay
Published: November 2020

The genomics of human development

Understanding the trajectory of a developing human requires an understanding of how genes are regulated and expressed. Two papers now present a pooled approach using three levels of combinatorial indexing to examine the single-cell gene expression and chromatin landscapes from 15 organs in fetal samples. Cao
et al.
focus on measurements of RNA in broadly distributed cell types and provide insights into organ specificity. Domcke
et al.
examined the chromatin accessibility of cells from these organs and identify the regulatory elements that regulate gene expression. Together, these analyses generate comprehensive atlases of early human development.

Science
, this issue p.
eaba7721
, p.
eaba7612
The ZSWIM8 ubiquitin ligase mediates target-directed microRNA degradation
Authors: Shi Charlie Y. , Kingston Elena R. , Kleaveland Benjamin , Lin Daniel H. , Stubna Michael W. , Bartel David P.
Published: November 2020

Turning the tables on microRNA decay

MicroRNAs help to regulate many genes in animal cells. Each microRNA associates with an Argonaute (AGO) protein, forming a complex in which the microRNA pairs with a messenger RNA (mRNA) target and AGO recruits factors that accelerate mRNA decay. However, for some unusual targets, the reverse occurs: Pairing to the target recruits factors that accelerate microRNA decay rather than degradation of the mRNA. Working independently, Shi
et al.
and Han
et al.
elucidate the mechanism of this phenomenon. They found that pairing to the unusual targets recruits a ubiquitin ligase that causes degradation of AGO, thereby exposing the microRNA to cellular nucleases. Mutating the ubiquitin ligase in diverse animals and cell types deregulates numerous microRNAs, implying that this phenomenon is widely deployed to sculpt microRNA levels.

Science
, this issue p.
eabc9359
, p.
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Cryptosporidium
-Biofilm Interactions: a Review
Authors: Lefebvre M. , Razakandrainibe R. , Villena I. , Favennec L. , Costa D.
Published: November 2020

Biofilms are increasingly implicated as playing a major role in waterborne cryptosporidiosis. This review aims to synthesize all currently available data on interactions between
Cryptosporidium
oocysts and biofilms.
Genome-Wide Functional Screen for Calcium Transients in Escherichia coli Identifies Increased Membrane Potential Adaptation to Persistent DNA Damage
Authors: Luder Rose , Bruni Giancarlo N. , Kralj Joel M.
Published: November 2020

All eukaryotic cells use calcium as a critical signaling molecule. There is tantalizing evidence that bacteria also use calcium for cellular signaling, but much less is known about the molecular actors and physiological roles.
Clinician and computer: a study on patient perceptions of artificial intelligence in skeletal radiography
Authors: York Thomas , Jenney Heloise , Jones Gareth
Published: November 2020

Background

Up to half of all musculoskeletal injuries are investigated with plain radiographs. However, high rates of image interpretation error mean that novel solutions such as artificial intelligence (AI) are being explored.

Objectives

To determine patient confidence in clinician-led radiograph interpretation, the perception of AI-assisted interpretation and management, and to identify factors which might influence these views.

Methods

A novel questionnaire was distributed to patients attending fracture clinic in a large inner-city teaching hospital. Categorical and Likert scale questions were used to assess participant demographics, daily electronics use, pain score and perceptions towards AI used to assist in interpretation of their radiographs, and guide management.

Results

216 questionnaires were included (M=126, F=90). Significantly higher confidence in clinician rather than AI-assisted interpretation was observed (clinician=9.20, SD=1.27 vs AI=7.06, SD=2.13), 95.4% reported favouring clinician over AI-performed interpretation in the event of disagreement.

Small positive correlations were observed between younger age/educational achievement and confidence in AI-assistance. Students demonstrated similarly increased confidence (8.43, SD 1.80), and were over-represented in the minority who indicated a preference for AI-assessment over their clinicians (50%).

Conclusions

Participant’s held the clinician’s assessment in the highest regard and expressed a clear preference for it over the hypothetical AI assessment. However, robust confidence scores for the role of AI-assistance in interpreting skeletal imaging suggest patients view the technology favourably.

Findings indicate that younger, more educated patients are potentially more comfortable with a role for AI-assistance however further research is needed to overcome the small number of responses on which these observations are based.
Job role and stress influence student movement during postpartum haemorrhage simulation: an exploratory study
Authors: Bican Rachel , Heathcock Jill C , Jedryszek Flora , Debarge Veronique , DeJonckheere Julien , Cybalski M C , Hanssens Sandy
Published: November 2020

Introduction

Postpartum haemorrhage is the leading cause of maternal death. Healthcare simulations are an educational tool to prepare students for infrequent high-risk emergencies without risking patient safety. Efficiency of movement in the simulation environment is important to minimize the risk of medical error. The purpose of this study was to quantify the movement behaviours of the participants in the simulation and evaluate the relationship between perceived stress and movement.

Methods

N=30 students participated in 10 high-fidelity medical simulations using an adult patient simulator experiencing a postpartum haemorrhage. The participants completed the State-Trait Anxiety Inventory prior to the simulation to measure perceived stress. Physical movement behaviours included walking around the simulation, time spent at bedside, arm movements, movements without purpose, looking at charts/vitals and total movement.

Results

Midwife (MW) students spent significantly more time walking (p=0.004) and looking at charts/vitals (p=<0.001) and significantly less time at bedside (p=<0.001) compared to obstetric (OB) students. The MW students demonstrated significantly more total movements compared to the OB students (p=<0.001). There was a significant, moderate, positive relationship between perceived stress and total movement during the simulation for the MW group (r=0.50, p=0.05). There was a trend for a moderate, positive relationship between perceived stress and total movement during the simulation for the OB group (r=0.46, p=0.10).

Conclusions

Physical movement during a simulation varies by job role and is influenced by perceived stress. Improved understanding of physical movement in the simulation environment can improve feedback, training and environmental set-up.
Legislative framework for animal research in the UK
Authors: Dennison Ngaire , Petrie Anja
Published: November 2020

Background

In 1986, the Animals (Scientific Procedures) Act 1986 (ASPA) replaced the Cruelty to Animals Act 1876, which had up until then protected animals used for ‘vivisection’ in the UK. ASPA itself was amended in 2013 to ensure the full implementation of EU Directive 2010/63/EU, the European Union legislation ‘on the protection of animals used for scientific purposes’, which is considered to be one of the most stringent ethical and welfare standards worldwide. ASPA allows (and controls) legitimate studies using animals in a framework designed to ensure that the potential harms to the animals are justified by the likely benefits of the research. While most veterinary surgeons working in clinical situations do not set out to perform ASPA‐regulated research, a desire to improve clinical outcomes for their patients or for the wider population means that, at times, they may approach or even cross the line from recognised veterinary practice into procedures or activities that require regulation under ASPA, the Veterinary Medicines Regulations (VMR) or other legislation.

Aim of the article

This article provides information on the legislation that exists to protect animals in research and explains how ASPA can affect all veterinary surgeons, and not just those working in research, due to its intersection with the Veterinary Surgeons Act and VMR.
Working while sick in context of regional unemployment: a Europe-wide cross-sectional study
Authors: Reuter Marvin , Dragano Nico , Wahrendorf Morten
Published: November 2020

Background

Research suggests that areas with high unemployment have lower rates of sickness absence, but the underlying mechanisms remain unclear. One assumption is that when unemployment is high people are more likely to work while being sick (discipline hypothesis). Against this background, we investigate the association between regional unemployment and sickness presenteeism. Second, we study interactions with factors of occupational disadvantage.

Methods

We combined survey data of 20 974 employees collected 2015 in 232 regions from 35 European countries with data on regional unemployment rates obtained from Eurostat. Presenteeism was assessed by the fraction of days worked while ill among all days with illness (presenteeism propensity). To investigate if unemployment was related to presenteeism, we estimated multi-level models (individuals nested in regions) that were adjusted for socio-demographic and occupational covariates to account for compositional differences of the regions.

Results

The mean presenteeism propensity was 34.8 (SD 40.4), indicating that workers chose presenteeism in 1 out of 3 days with sickness. We found that a change in unemployment by +10 percentage points was associated with a change in presenteeism by +5 percentage points (95% CI 1.2 to 8.6). This relationship was more pronounced among workers with low salary, low skill-level, and industrial and healthcare workers.

Conclusion

Our results support the assumption that high unemployment elevates presenteeism, and that people in disadvantaged occupations are particularly affected. Policies managing presenteeism should consider the labour market context, particularly during the aftermath of the COVID-19 pandemic.
Reactions to messages about smoking, vaping and COVID-19: two national experiments
Authors: Grummon Anna H , Hall Marissa G , Mitchell Chloe G , Pulido Marlyn , Mendel Sheldon Jennifer , Noar Seth M , Ribisl Kurt M , Brewer Noel T
Published: November 2020

Introduction

The pace and scale of the COVID-19 pandemic, coupled with ongoing efforts by health agencies to communicate harms, have created a pressing need for data to inform messaging about smoking, vaping, and COVID-19. We examined reactions to COVID-19 and traditional health harms messages discouraging smoking and vaping.

Methods

Participants were a national convenience sample of 810 US adults recruited online in May 2020. All participated in a smoking message experiment and a vaping message experiment, presented in a random order. In each experiment, participants viewed one message formatted as a Twitter post. The experiments adopted a 3 (traditional health harms of smoking or vaping: three harms, one harm, absent) × 2 (COVID-19 harms: one harm, absent) between-subjects design. Outcomes included perceived message effectiveness (primary) and constructs from the Tobacco Warnings Model (secondary: attention, negative affect, cognitive elaboration, social interactions).

Results

Smoking messages with traditional or COVID-19 harms elicited higher perceived effectiveness for discouraging smoking than control messages without these harms (all p <0.001). However, including both traditional and COVID-19 harms in smoking messages had no benefit beyond including either alone. Smoking messages affected Tobacco Warnings Model constructs and did not elicit more reactance than control messages. Smoking messages also elicited higher perceived effectiveness for discouraging vaping. Including traditional harms in messages about vaping elicited higher perceived effectiveness for discouraging vaping (p <0.05), but including COVID-19 harms did not.

Conclusions

Messages linking smoking with COVID-19 may hold promise for discouraging smoking and may have the added benefit of also discouraging vaping.
‘Farmer behaviour may affect the actual contribution of badger perturbation to bTB’
Authors: Enticott Gareth
Published: November 2020

Gareth Enticott argues that precise assessment of the effect of badger perturbation to bTB incidence can only be made by analysing farmer behaviour and its effects in badger culling zones.
Effects of combined exercise training and Chlorella intake on vasorelaxation mediated by nitric oxide in aged mice
Authors: Fujie Shumpei , Hasegawa Natsuki , Horii Naoki , Inoue Kenichiro , Uchida Masataka , Iemitsu Motoyuki
Published: November 2020

Chronic Chlorella intake and aerobic exercise training reduce arterial stiffness and increase circulating nitric oxide (NO) levels, which has beneficial effects. This study aimed to clarify the combined aortic NO-mediated effects of chronic Chlorella intake and aerobic exercise training on endothelial vasorelaxation in aged mice. In this study, 38-week-old male senescence-accelerated mouse prone 1 (SAMP1) mice were divided into aged sedentary control (Con), aerobic exercise training (AT; voluntary wheel running for 12 weeks), Chlorella intake (CH; 0.5% Chlorella powder in normal diet), and AT and CH combined (AT+CH) groups. Endothelium-dependent vasorelaxation by addition of acetylcholine to the isolated mouse aortic rings was significantly higher in the AT, CH, and AT+CH groups than in the Con group; a significantly greater effect was seen in the AT+CH group than in the AT and CH groups. Similarly, plasma and arterial nitrite/nitrate levels and arterial endothelial NO synthase phosphorylation were significantly higher in the AT, CH, and AT+CH groups than in the Con group; the AT+CH group had higher values than the AT and CH groups. Thus, chronic Chlorella intake combined with aerobic exercise training had pronounced effects on endothelial vasorelaxation in aged mice via an additive increase in arterial NO production.

Novelty: Endothelium-dependent vasorelaxation was improved by Chlorella intake and exercise. Chlorella intake and exercise increased arterial Akt/eNOS/NO signaling. This combination approach further improved vasorelaxation via arterial NO production.
Photovoltaic properties of ITO/p-Si heterojunction prepared by pulsed laser deposition
Authors: Ismail Raid A. , Abdulrazzaq Omar A. , Ali Abdullah M.
Published: November 2020

In this study, indium tin oxide (ITO) was deposited onto sapphire and low resistive p-Si substrates using pulsed laser deposition (PLD) technique. The optical energy gap of ITO deposited on the sapphire substrate was 3.7 eV at room temperature. Photoluminescence (PL) of ITO shows an emission of broad peak at 524 nm. Photovoltaic (PV) characteristics of the n-ITO/p-Si heterojunction are examined and showed conversion efficiency [Formula: see text] of 1.8%. The open circuit voltage [Formula: see text] for this cell was 0.49 V while the short circuit current density [Formula: see text] was 17.4 mA/cm2. The fill factor of this cell was 22%. The ideality factor of ITO/Si heterojunction is about 3.1. The barrier height [Formula: see text] of the heterojunction was determined from I–V characteristics and was 0.83 eV. The responsivity of the heterojunction was measured and the maximum value of responsivity was 0.5 A/W without bias voltage. The minority carrier lifetime of the solar was measured using open circuit voltage decay (OCVD) method and found to be 227 [Formula: see text]s.
MODELING CHOLERA TRANSMISSION UNDER DISEASE CONTROL MEASURES
Authors: BROWN MARGARET , JIANG MIKO , YANG CHAYU , WANG JIN
Published: November 2020

We present a new mathematical model to investigate the transmission dynamics of cholera under disease control measures that include education programs and water sanitation. The model incorporates the impact of education programs into the disease transmission rates and that of water sanitation into the environmental pathogen dynamics. We conduct a detailed analysis to the autonomous system of the model and establish the local and global stabilities of its equilibria that characterize the threshold dynamics of cholera. We then perform an optimal control study on the general model with time-dependent controls and explore effective approaches to implement the education programs and water sanitation while balancing their costs. Our analysis and simulation highlight the complex interaction among the direct and indirect transmission pathways of the disease, the intrinsic growth of the environmental pathogen and the impact of multiple control measures, and their roles in collectively shaping the transmission dynamics of cholera.
Conceptual modelling for the design of groundwater control systems
Authors: Preene Martin
Published: November 2020

Groundwater control is required to allow excavations and tunnels to be formed in stable and workably dry conditions below groundwater level. Representative and relevant conceptual models are an essential requirement for the successful development of groundwater control schemes. Prior to construction, conceptual models can aid the planning of ground investigations to help select borehole depths, borehole locations and hydrogeological testing methods. During construction the effectiveness of groundwater control techniques will vary with different hydrogeological conditions and the hydraulic conductivity of the strata. A sound conceptual model reduces the risk of designs being developed using inappropriate approaches to groundwater control. Common misconceptions include the assumption of a single aquifer (where multiple aquifers and aquitards exist) and cases where significant transmissive zones (which may act as aquifers) are not identified. Other errors include assuming that groundwater levels reported during site investigations are representative of maximum levels that may occur during construction, or not considering the risk of external impacts caused by groundwater control methods. A suggested framework to produce better models is problem–solution–technology–impacts. This framework can avoid some of the common misconceptions that have resulted in problems during the design and implementation of groundwater control schemes.

Thematic collection:
This article is part of the Ground models in engineering geology and hydrogeology collection available at:
https://www.lyellcollection.org/cc/Ground-models-in-engineering-geology-and-hydrogeology
Unraveling the Roles of La Substitution for Different Transition Metals on P2-Na0.67Mn0.6Ni0.2Co0.2O2 Cathode Materials
Authors: Wang Huibo , Li Ling , Han Wenze , Guo Hao , Sun Limei , Liu Xiangfeng
Published: November 2020

P2-type layered transitional metal oxides as the promising cathode materials for sodium-ion batteries (SIBs) have attracted great attention. But their poor cycling stability and inferior rate capability restrict the practical applications. Foreign elements doping has been considered as one effective strategy to overcome these shortcomings. But the roles of the dopants are still poorly understood. Herein, we have taken La doping to modulate the crystal and electronic structure, and systematically investigated the different effects of La substitution for Mn, Ni and Co on the structure and electrochemical properties of P2-Na0.67Mn0.6Ni0.2Co0.2O2 cathode materials. The substitution of La reduces Mn3+ in the crystal lattice which alleviates Jahn−Teller distortion and reduces the collapse of the transition metal layer caused by the dissolution of Mn3+. Due to the large La–O bonding energy, the substitution of La for Mn, Ni and Co shortens O–O and TM–O bond length, and the thickness of TMO2, which all enhance the structure stability. In addition, the substitution of La for Mn, Ni and Co also expands the interlayer spacing and Na–O bond length enhancing Na+ diffusion kinetics. The substitution of La for Mn shows better rate capability and cycling stability than the substitution for Ni and Co. It can provide a discharge capacity of 86 mAh g−1 at a high current density of 8C (1600 mA g−1) with a capacity retention rate of 95%. This study also presents some insights into modulating the lattice and electronic structure by elements doping to optimize the electrochemical performances.
A Facile Approach for the Electrochemical Sensing of Dopamine using Paper-Based PEDOT:PSS/RGO Graphene Biosensor
Authors: Settu Kalpana , Huang Yu-Ming , Zhou Sheng-Xuan
Published: November 2020

In this study, we have developed a paper-based electrochemical biosensor for dopamine (DA) detection. For this purpose, a screen-printed graphene electrode (SPGNE) was printed on a paper substrate, and the electrode surface was modified with PEDOT:PSS/RGO. The fabricated sensor was characterized by analyzing the capacitance, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) measurements. Differential pulse voltammetry (DPV) was employed for the quantitative detection of dopamine. The paper-based SPGNE biosensor developed in this study could detect dopamine in a linear range from 0.0125 to 0.1 mM with a sensitivity of 24.9 μA mM−1. The reliability of the developed biosensor for dopamine detection was assessed by using normal serum samples. The paper-based graphene biosensor proposed in this study could be low-cost and eco-friendly, and its ability to determine the dopamine from real serum samples showed promising results. The developed SPGNE dopamine-sensing biosensor could be potentially applied for the early-stage diagnosis of various neurological diseases/disorders.
No influence on tumor growth by intramuscular injection of adipose-derived regenerative cells: safety evaluation of therapeutic angiogenesis with cell therapy
Authors: Suzuki Junya , Shimizu Yuuki , Tsuzuki Kazuhito , Pu Zhongyue , Narita Shingo , Yamaguchi Shukuro , Katagiri Takeshi , Iwata Etsuo , Masutomi Tomohiro , Fujikawa Yusuke , Shibata Rei , Murohara Toyoaki
Published: November 2020

In this study, we demonstrated that local injection of ADRCs can promote angiogenesis in response to tissue ischemia without promoting remote tumor growth in a mouse model. Our findings indicate that therapeutic angiogenesis to the ischemic hindlimb using ADRCs seems to be safe regarding remote tumor growth.
E-wave asymmetry elucidates diastolic ventricular stiffness-relaxation coupling: model-based prediction with in vivo validation
Authors: Amrute Junedh M. , Zhang David , Padovano William M. , Kovács Sándor J.
Published: November 2020

Although diastolic stiffness and relaxation are considered independent chamber properties, the cardio-hemic inertial oscillation that generates E-waves obeys Newton’s law. E-waves vary with heart rate requiring simultaneous change in stiffness and relaxation. By retrospective analysis of human heart-rate varying transmitral Doppler-data, we show that diastolic stiffness and relaxation are coupled and that the coupling manifests through E-wave asymmetry, quantified through a parametrized diastolic filling model-derived dimensionless parameter, which only depends on deceleration time and acceleration time, readily obtainable via standard echocardiography.
Membrane proteomic profiling of the heart: past, present, and future
Authors: Lee Shin-Haw , Kim Da Hye , Kuzmanov Uros , Gramolini Anthony O.
Published: November 2020

Cardiovascular diseases remain the most rapidly rising contributing factor of all-cause mortality and the leading cause of inpatient hospitalization worldwide, with costs exceeding $30 billion annually in North America. Cell surface and membrane-associated proteins play an important role in cardiomyocyte biology and are involved in the pathogenesis of many human heart diseases. In cardiomyocytes, membrane proteins serve as critical signaling receptors, Ca2+ cycling regulators, and electrical propagation regulators, all functioning in concert to maintain spontaneous and synchronous contractions of cardiomyocytes. Membrane proteins are excellent pharmaceutical targets due to their uniquely exposed position within the cell. Perturbations in cardiac membrane protein localization and function have been implicated in the progression and pathogenesis of many heart diseases. However, previous attempts at profiling the cardiac membrane proteome have yielded limited results due to poor technological developments for isolating hydrophobic, low-abundance membrane proteins. Comprehensive mapping and characterization of the cardiac membrane proteome thereby remains incomplete. This review will focus on recent advances in mapping the cardiac membrane proteome and the role of novel cardiac membrane proteins in the healthy and the diseased heart.

Listen to this article's corresponding podcast at https://ajpheart.podbean.com/e/membrane-proteomic-profiling-of-the-heart/ .
Potential of Using Shear Wave Elastography in the Clinical Evaluation and Monitoring of Changes in Masseter Muscle Stiffness
Authors: Olchowy Cyprian , Więckiewicz Mieszko , Sconfienza Luca Maria , Łasecki Mateusz , Seweryn Piotr , Smardz Joanna , Hnitecka Sylwia , Dominiak Marzena , Olchowy Anna
Published: November 2020

The study aimed to evaluate masseter muscle stiffness in adult healthy volunteers referred to a massage treatment and also to investigate whether shear-wave elastography can be used to monitor the effect of massage on the masseter muscle. The study included 21 healthy volunteers, who were subjected to a 30-minute massage of the masseter muscle. Muscle stiffness was measured by shear-wave elastography before and directly after the massage. Pain during the massage was assessed using the visual analogue scale (VAS). The data of 20 patients (one excluded due to severe pain) with a median age of 34.5 years were analysed. The stiffness values were 11.46 ± 1.55 kPa before and 8.97 ± 0.96 kPa after the massage (

p
<
0.0001

). The mean drop was 2.49 ± 1.09 kPa. The greatest decrease was observed in people with higher elasticity values before the massage (r = 0.79;

p
<
0.0001

). The median intensity of pain was 7.2 (range: 6–9.5). We concluded that shear-wave elastography is a sensitive tool to monitor changes in the stiffness of the masseter muscle.
In Vivo Plasticity at Hippocampal Schaffer Collateral-CA1 Synapses: Replicability of the LTP Response and Pharmacology in the Long-Evans Rat
Authors: Ahnaou A. , White E. , Biermans R. , Manyakov N. V. , Drinkenburg W. H. I. M.
Published: November 2020

Broad issues associated with non-replicability have been described in experimental pharmacological and behavioral cognitive studies. Efforts to prevent biases that contribute to non-replicable scientific protocols and to improve experimental rigor for reproducibility are increasingly seen as a basic requirement for the integrity of scientific research. Synaptic plasticity, encompassing long-term potentiation (LTP), is believed to underlie mechanisms of learning and memory. The present study was undertaken in Long-Evans (LE) rats, a strain of rat commonly used in cognitive behavioral tests, to (1) compare three LTP tetanisation protocols, namely, the high-frequency stimulation (HFS), the theta-burst stimulation (TBS), and the paired-pulse facilitation (PPF) at the Schaffer collateral-CA1 stratum radiatum synapse and to (2) assess sensitivity to acute pharmacology. Results: (1) When compared to Sprague-Dawley (SD) rats, the HFS using a stimulus intensity of 50% of the maximum slope obtained from input/output (I/O) curves elicited lower and higher thresholds of synaptic plasticity responses in SD and LE rats, respectively. The 2-train TBS protocol significantly enhanced the LTP response in LE rats over the 5- and 10-train TBS protocols in both strains, and the

5
×
TBS

protocol inducing a subthreshold LTP response was used in subsequent pharmacological studies in LE rats. The PPF protocol, investigating the locus of the LTP response, showed no difference for the selected interstimulus intervals. (2) Scopolamine, a nonspecific muscarinic antagonist, had a subtle effect, whereas donepezil, an acetylcholinesterase inhibitor, significantly enhanced the LTP response, demonstrating the sensitivity of the TBS protocol to enhanced cholinergic tone. MK-801, a noncompetitive N-methyl-D-aspartate (NMDA) antagonist, significantly reduced LTP response, while memantine, another NMDA antagonist, had no effect on LTP response, likely associated with a weaker TBS protocol. PQ10, a phosphodiesterase-10 inhibitor, significantly enhanced the TBS-induced LTP response, but did not change the PPF response. Overall, the results confirm the strain-dependent differences in the form of synaptic plasticity, replicate earlier plasticity results, and report effective protocols that generate a relatively subthreshold margin of LTP induction and maintenance, which are suitable for pharmacology in the LE rat strain mainly used in cognitive studies.
Culturing Articular Cartilage Explants in the Presence of Autologous Adipose Tissue Modifies Their Inflammatory Response to Lipopolysaccharide
Authors: Pearson Wendy , Garland Anna E. N. , Nixon Ashley , Cant John P. , Hurtig Mark B.
Published: November 2020

The purpose of the current study was to explore the effect of autologous adipose tissue on cartilage responses to lipopolysaccharide (LPS). We hypothesized that LPS elicits an inflammatory response in cartilage, and that response is augmented in the presence of adipose tissue. Furthermore, we hypothesized that this augmented inflammatory response is due, at least in part, to increased exposure of cartilage to adipose tissue-derived c3a. Porcine cartilage explants from market-weight pigs were cultured in the presence or absence of autologous adipose tissue for 96 hours, the final 48 hours of which they were stimulated with LPS (0 or 10 μg/mL). Adipose tissue explants were also cultured alone, in the presence or absence of LPS. Media from all cartilage treatments was assayed for c3a/c3a des Arg, PGE2, GAG, and NO, and the viability of cartilage tissue was determined by differential fluorescent staining. Media from adipose tissue explants was assayed for c3a/c3a des Arg and PGE2. LPS produced a significant increase in PGE2, GAG, and NO production when cartilage was cultured in the absence of adipose tissue. Coculture of adipose tissue prevented a significant increase in PGE2 in cartilage explants. There was no effect of adipose tissue on LPS-induced GAG or NO, but the presence of adipose tissue significantly reduced cell viability in LPS-stimulated cartilage explants. Adipose tissue explants from lean animals reduced inflammatory responses of cartilage to LPS via a c3a/c3a des Arg-independent mechanism and were associated with a significant decline in cell viability. Thus, contrary to our hypothesis, adipose tissue from lean animals does not augment the inflammatory response of cartilage to stimulation by LPS. The mechanism of modulatory effects of adipose tissue on LPS-induced increase in PGE2 and decline in chondrocyte viability requires further research but appears to have occurred via a mechanism that is independent of adipocentric c3a/c3a des Arg.
Prevalence, Intensity, and Associated Factors of Schistosoma mansoni among School Children in Northwest Ethiopia
Authors: Zeleke Ayalew Jejaw , Addisu Ayenew , Tegegne Yalewayker
Published: November 2020

Background. Schistosomiasis is one of the Neglected Tropical Diseases in Ethiopia, and its burden may show variations from time to time across different regions. Thus, this study was aimed at determining the prevalence, intensity, and associated risk factors of Schistosoma mansoni (S. mansoni) among schoolchildren in Northwest Ethiopia. Methods. A school-based cross-sectional study was conducted. A multistage sampling technique was used to select the study participants. Stool specimens were collected and examined using two-slide Kato-Katz method. Data were analyzed using SPSS version 20 software. Multivariate logistic regression analysis was used to identify risk factors.

p

values less than 0.05 were taken as statistically significant. Result. A total of 786 schoolchildren were participated in this study. The prevalence of S. mansoni was 33.5%. The mean egg count of the parasite among the infected study participants was 523.665 eggs per gram (epg) of stool. Thirty-seven, 42, and 21 percent of the study participant’s infection were due to light, moderate, and heavy infection intensities, respectively. Age of 8-11 years old (

AOR
=
1,687

,

95
%
CI
=
1.163
,
2.892

), 5th-8th grade level (

AOR
=
2.280

,

95
%
CI
=
1.348
,
3.856

), residing in Chuahit District (

AOR
=
95.559

,

95
%
CI
=
12.945
,
705.419

), and using untreated water for domestic supply (

AOR
=
1.724

,

95
%
CI
=
1.457
,
2.148

) were found to be risk factors for S. mansoni infection. Conclusion. High prevalence of S. mansoni and relatively higher proportion of moderate intensity of infection in this study imply that schistosomiasis is still one of the major public health problems in Northwest Ethiopia. It is also highlighted that study sites, provision of water supply, age, and grade level of the schoolchildren were identified as a risk factors for the disease.
Instability Model of a Coal Wall with Large Mining Height under Excavation Unloading Conditions
Authors: Li Lei , zhang Feng
Published: November 2020

On the basis of the stress field characteristics of surrounding rocks at a coal wall on a working face with a large mining height, the theories of unloading rock mass mechanics and fracture mechanics were used to establish a model of the excavation unloading field effect of the coal wall, and its instability mechanism under the action of unloading stress field was analyzed. Results show that the coal mining process is the unloading process of coal and rock masses, and the stress field of surrounding rocks at the coal wall turns into an unloading stress field that consists of original and unloading stresses. Under the action of unloading stress field, cracks in the coal wall will undergo instability, propagation, and combination in the form of composite‐type cracks and will gradually evolve into a wedge structure. The wedge stability is inversely related to roof pressure P0, unloading force T, and intersection angle φ of structural planes. Elevating the wall‐supporting force Ph, the initial supporting force of supports on the working face and the cohesion C of coal body can effectively control the occurrence of coal wall caving accidents and contribute to the safe mining of working faces with a large mining height.
Comparison of Different In Vivo Animal Models of Brachial Plexus Avulsion and Its Application in Pain Study
Authors: Xian Hang , Xie Rougang , Luo Ceng , Cong Rui
Published: November 2020

Brachial plexus injuries (BPIs) are high-energy trauma that can result in serious functional problems in the affected upper extremities, and brachial plexus avulsion (BPA) could be considered the most severe type of them. The booming occurrence rate of BPA brings up devastating impact on patients’ life. Complications of muscle atrophy, neuropathic pain, and denervation-associated psychological disorders are major challenges in the treatment of BPA. Animal models of BPA are good vehicles for this kind of research. Full understanding of the current in vivo BPA models, which could be classified into anterior approach avulsion, posterior approach avulsion, and closed approach avulsion groups, could help researchers select the appropriate type of models for their studies. Each group of the BPA model has its distinct merits and demerits. An ideal BPA model that can inherit the advantages and make up for the disadvantages is still required for further exploration.