bluuebunny/crossref_metadata_2025 huggingface dataset:
W-HYDRA: a new experimental platform for the Water-Cooled Lead Lithium Breeding Blanket
Authors: Arena P. , Del Nevo A. , Eboli M. , Gonfiotti B. , Maccari P. , Marinari R. , Tincani A. , Badodi N. , Bongiovì G. , Catanzaro I. , Galleni F. , Risi C. , Sanasi L.L. , Tarallo A. , Vannoni A.
Published: May 2024

In the framework of the activities coordinated by the EUROfusion consortium, the Water thermal-HYDRAulic (W-HYDRA) experimental platform is being built at the ENEA Brasimone Research Centre in order to support the development of the Water-Cooled Lead Lithium (WCLL) Breeding Blanket (BB). In particular, this infrastructure will make possible the installation and testing of prototypical mock-ups under relevant working conditions, such as the First Wall (FW), the manifold and the Steam Generator (SG). Moreover, it will represent an integral test facility for the investigation of phenomena characteristic of WCLL BB concept, such as the PbLi/water interaction. Finally, the collection of data coming from the different planned experimental campaigns will allow to qualify and validate numerical models and codes currently adopted for the design of components, as well as for the modelling of complex phenomena typical of the WCLL BB. In order to come to a definitive design of the different facilities constituting the experimental platform, several design analyses assessing the thermal, hydraulic and structural performances of the different facilities and components are necessary. The paper reports a highlight of the W-HYDRA platform with a general description of the facilities. Some of the most relevant design studies carried out so far are reported as well, highlighting their impact on the evolution of the design.
Assessment of runaway electron beam termination and impact in ITER
Authors: Bandaru V. , Hoelzl M. , Bergström H. , Artola F.J. , Särkimäki K. , Lehnen M. ,   the JOREK Team
Published: May 2024

The vertical motion and shrinking of the cold plasma column after a tokamak disruption leads to a natural decrease in the edge safety factor when most of the current is carried by runaway electrons (REs). Reaching a low edge safety factor can potentially cause a strong plasma instability. We present magnetohydrodynamic simulations of the termination of a post-disruption plateau-phase RE beam in ITER when the edge safety factor falls close to two. Growth of instabilities is observed to result in stochastization of the magnetic field and a prompt loss of REs. As RE impact must be mitigated in ITER, the effect of parameters that influence the final termination have been assessed. Higher background plasma resistivity is seen to cause larger mode magnitudes and stronger stochastization, leading to less remnant REs after the termination event. Lower ion-densities also project a qualitatively similar behavior although weaker in effect. Using computations from a wall collision model, the ensuing load distribution on the first-wall is also presented.
Constant speed random particles spontaneously confined on the surface of an expanding sphere
Authors: Serva Maurizio
Published: May 2024

The particles that we describe here can only move at the speed of light c in three-dimensional space. The velocity, which randomly but continuously changes direction, can be represented as a point on the surface of a sphere of constant radius c, and its trajectories may only connect points of this variety. The Wiener process that we use to describe the velocity dynamics on the surface of the sphere is anisotropic since the infinitesimal variation of the velocity is not only always orthogonal to the velocity itself (which guarantees a constant speed), but also to the position. This choice for the infinitesimal variation of the velocity is the one that best slows down the diffusion of particles in space by random motion at the speed of light. As a result of these dynamics, the position of the particles spontaneously remain confined on the surface of an expanding sphere whose radius increases, for large times, as the square root of time.
Real-time signal detection for Cyclotron Radiation Emission Spectroscopy measurements using antenna arrays
Authors: Ashtari Esfahani A. , Böser S. , Buzinsky N. , Carmona-Benitez M.C. , Claessens C. , de Viveiros L. , Fertl M. , Formaggio J.A. , Foust B.T. , Gaison J.K. , Grando M. , Hartse J. , Heeger K.M. , Huyan X. , Jones A.M. , Jones B.J.P. , Kazkaz K. , LaRoque B.H. , Li M. , Lindman A. , Marsteller A. , Matthé C. , Mohiuddin R. , Monreal B. , Mucogllava B. , Mueller R. , Negi A. , Nikkel J.A. , Novitski E. , Oblath N.S. , Oueslati M. , Peña J.I. , Pettus W. , Reimann R. , Robertson R.G.H. , Rybka G. , Saldaña L. , Slocum P.L. , Stachurska J. , Sun Y.-H. , Surukuchi P.T. , Tedeschi J.R. , Telles A.B. , Thomas F. , Thorne L.A. , Thümmler T. , Van De Pontseele W. , VanDevender B.A. , Weiss T.E. , Wendler T. , Ziegler A. ,   The Project 8 collaboration
Published: May 2024

Cyclotron Radiation Emission Spectroscopy (CRES) is a technique for precision measurement of the energies of charged particles, which is being developed by the Project 8 Collaboration to measure the neutrino mass using tritium beta-decay spectroscopy. Project 8 seeks to use the CRES technique to measure the neutrino mass with a sensitivity of 40 meV, requiring a large supply of tritium atoms stored in a multi-cubic meter detector volume. Antenna arrays are one potential technology compatible with an experiment of this scale, but the capability of an antenna-based CRES experiment to measure the neutrino mass depends on the efficiency of the signal detection algorithms. In this paper, we develop efficiency models for three signal detection algorithms and compare them using simulations from a prototype antenna-based CRES experiment as a case-study. The algorithms include a power threshold, a matched filter template bank, and a neural network based machine learning approach, which are analyzed in terms of their average detection efficiency and relative computational cost. It is found that significant improvements in detection efficiency and, therefore, neutrino mass sensitivity are achievable, with only a moderate increase in computation cost, by utilizing either the matched filter or machine learning approach in place of a power threshold, which is the baseline signal detection algorithm used in previous CRES experiments by Project 8.
Conceptual design and simulated performance of the Barrel part of gamma array for the experimental terminal at HFRS of HIAF
Authors: Li Z.Y. , Yan D. , Wang S.T. , Yu Y.H. , Sun Z.Y. , Yue K. , Tang S.W. , Zhang X.H. , Ong H.J. , Fang F. , Zhang Y.J. , Xu X.D. , Sun Y.Z. , Jin S.Y. , Ma S.B.
Published: May 2024

The Barrel of γ array, consisting of 640 CsI(Tl)
crystals and covering a polar angle range from 36.4° to
135.6°, has been designed for the experimental terminals at
High energy FRagment Separator of High-Intensity heavy-ion
Accelerator Facility in Huizhou. Together with the existing Endcap,
consisting of 1024 CsI(Tl) crystals and covering a polar angle from
15.6° to 36.4°, at the External Target Facility in
Lanzhou to form a new γ array, it is expected to meet the
experimental requirements for in-beam γ-ray spectroscopy
technique. A Monte Carlo code based on Geant4 was implemented to
study the performance of the new γ array. Taking into account
the Doppler correction and the intrinsic energy resolution of the
detector, the energy resolution is 5.4% (FWHM) for the Endcap and
9.8% (FWHM) for the Barrel when the energy of the emitted
 γ-ray is 1 MeV in the Center-of-Mass frame with the beam
energy of 500 MeV/u (beam velocity β = 0.759). The full-space
photopeak efficiency is greater than 40% when the energy of the
emitted γ-ray is less than 5 MeV in the Center-of-Mass frame
and the beam energy is less than 700 MeV/u (β = 0.821). Such
performance can satisfy most of the physics requirements for in-beam
 γ-ray spectroscopy experiments.
Statistical evaluation of effect of anthropometric measurements on adolescent idiopathic scoliosis
Authors: Odetunmibi O. A. , Akingbade T. J. , Ale O. S. , Oghonyon G. J. , Oluwadare J. R.
Published: May 2024

Scoliosis is a deformity in which there is sideways curvature to the spine. Curves are often S shaped or C shaped. Most common type is the idiopathic type which occurs in 10-12 years of age and early teens, females are more affected than males while the body is growing fast and the curve is commonly to the right side of the body. It however affect all ages of about 3% of general population. This study was set out to evaluate statistically, the effect of age, gender and anthropometric measurements (such as height, weight and body mass index) to the curve formed using 51 patients from Lagos State University Teaching Hospital, Ikeja. It was discovered from the analysis that the ailment is common among females than males. The result also shows that the curve is most common to right hand side. The test of hypothesis conducted reveals that the anthropometric measurements of height, weight and body mass index though positively correlated with but do not have significant effect on the Adolescent Idiopathic Scoliosis curve.
A Review of Fabrication Techniques and Optimization Strategies for Microbial Biosensors
Authors: Ahuekwe E.F. , Akinyele A.F. , Benson A.E. , Oniha M.I. , Oziegbe O.
Published: May 2024

Challenges of stability and specificity associated with early generation sensors necessitate the fabrication and optimization of microbial biosensors. More so, the global biosensors market size currently valued at USD25.5 billion in 2021 is expected to grow at a compound annual growth rate (CAGR) of 7.5% to USD36.7 billion in 2026. Microbial biosensors are bioanalytical systems that integrate microorganisms with a physical transducer to generate signals, thus, aiding the identification of analytes. The biosensors are fabricated through a series of steps comprising microbe selection, immobilization onto a matrix, microfabrication, calibration, and validation. The transducers integrated microorganisms generate quantifiable signals, enabling real-time monitoring of a diversity of analytes within food samples. The optimization strategies are scrutinized, with a particular focus on the integration of sundry nanoparticles, such as magnetic, gold, and quantum-dot nanoparticles, which enhance sensor performance. Distinct advantages offered by microbial biosensors promise to revolutionize food quality assessment via cost-effectiveness, rapid sample testing, and the ability to provide access to real-time data. Literature have highlighted certain limitations including interference from complex matrices, instability of microorganisms, and microbial lifespan. In assessing their economic importance, a comparative analysis is presented against conventional food analytical methods like ELISA, PCR, and HPLC; thus, highlighting the unique strengths of microbial biosensors. The future perspectives focus on the potential of the technology in addressing the need for continuous monitoring challenges, and research for further improvements in the biocompatibility of fabrication processes and long-term reusability.
Promoting Sustainable Development in Combating Schistosomiasis through Community-Centric Approaches: The Role of Social Empowerment and Education in Ondo State
Authors: Balogun D. O. , Nwinyi O. C. , Isibor P. O. , Adewale B. , Oyegbade S. A. , Mameh E. O , Aririguzoh V. O
Published: May 2024

Schistosomiasis has been reported to be the most common parasitic disease after malaria capable of affecting over 249 million individuals in lower-income countries. The disease is caused by a blood fluke from the genus Schistosoma and can be either chronic or acute in several patients depending on the worm burden. Poor sanitation and lack of potable water are major predisposing factors for the sustained transmission of schistosomiasis in several communities in Africa. In Nigeria, 24 million cases are being reported in all states, with over 100 million individuals at risk of the infection due to the disease being endemic in the region. This disease is made worse when there is a co-infection of urinary tract infections (UTIs) or sexually transmitted diseases (STDs). In Ondo state Nigeria, urinary schistosomiasis is called Atosiaja, blood fluke, or snail fever. The disease is endemic in several communities in Ondo states due to little or no access to clean water which increases the contact of villagers to natural flowing rivers and streams that are natural breeding sites for the intermediate hosts. This systematic review was carried out to evaluate the prevalence of schistosomiasis in communities of Ondo state, Nigeria. The review was conducted through a literature search using two scientific databases which focuses on the prevalence and intensity of schistosomiasis infection in communities of Ondo state covering the period 2017 to 2022. This review looks at the relationship between sustainable development initiatives and the prevalence of schistosomiasis in Ondo state. By addressing critical issues such as water quality, community education and integrated vector management as long-term solutions to reduce the burden of schistosomiasis in Ondo state. This holistic approach will contribute overall to improvements in public health and the environment.
Influence of Virtual Learning Environments on Student Achievement for Sustainable Development
Authors: Owoseni A. O. , Babalola O. D. , Ibem E. O. , Opoko A. P.
Published: May 2024

As a result of the global pandemic, in-person lecture delivery method was interrupted and thus, the necessitated adoption of Virtual Learning Environments (VLEs) for the continuity of learning. However, considering that architectural education is hands-on and field-dependent, continuous design studio mentoring is expedient. This study therefore explored the potential of adopting VLE, especially in hands-on related disciplines and how this fosters student achievement in driving sustainable development. Descriptive statistics were employed to analyse quantitative data gathered from a randomly selected sample of architecture students representing three private universities in Nigeria. Findings from this research revealed that learning continued during the lockdown within the subject discipline. Notably, 86.6% of respondents utilized virtual meeting software like Zoom, Google Meet, Microsoft Teams, and Cisco WebEx, while 12.4% utilized Learning Management Systems (LMS) such as Moodle. Additionally, accessible facilities like comfortable study areas, a steady power supply, internet connectivity, and studio materials contributed to a successful VLE experience. This research strongly advocates for the continuation of hybrid learning in architectural education, combining physical and virtual modes to deliver enriching and memorable learning experiences to enhance education for sustainable development.
Modeling of Wellbore Heat Transfer in Geothermal Production Well
Authors: Izuwa N. C. , Okereke N. U. , Nwanwe O. I. , Ejiga E. G. , Ekueme S. T. , Chikwe A.O. , Dike H. , Olabode O. , Ohaegbulam C. M.
Published: May 2024

Electricity supply in Nigeria has been insufficient to aid development. It has also been observed that fossil fuels that supply energy has not been friendly to the environment, as a result an alternative energy source is needed. Geothermal energy has come to fill this gap. This work modelled wellbore heat transfer in geothermal wells and investigated the best heat mining fluid that will conserve heat during heat transfer at the wellbore during heat production. This work employed the mechanisms that greenhouse gases use to absorb heat from the sun and retain it to warm the earth. Simulation of heat extraction capability of steam and CO2 were studied. It was observed at reservoir conditions (248 °F) that steam Mass heat capacity (2.433 KJ/kg °F) is higher than that of CO2 (1.088 KJ/kg °F). At 204. 8 °F mass heat capacity of CO2 is 1.1915KJ/kg OF and that of steam is 2.4058 KJ/kg °F. This implies that steam retains more heat than CO2. From the study at wellbore fluid temperature of 276.8 °F, and at a flow rate of 1300 lb/hr, the wellbore heat transfer from steam (0.158 mmbtu/day) is slightly higher than that of CO2 (0.105 mmbtu/day). CO2 conserves more heat than steam when used as a heat transfer fluid. The heat transfer capabilities of the mining fluids determine the production capability of the heat resources and the quantity of electricity generation. The study recommended CO2 deployment as heat mining fluid in the exploitation of heat in geothermal resources in Nigeria. This will reduce the greenhouse effect of CO2 in our environment while also encouraging rapid development and economic growth, more especially with the rising cost of energy from fossil. Availability of geothermal energy will increase the supply of electricity in Nigeria.
Theoretical Study of Quantum Efficiency and Spectral Response of Solar Cells
Authors: James U. E. , Dim C. C. , Akinyemi M. L. , Ogunrinola I. E.
Published: May 2024

A theoretical study of Quantum Efficiency (QE) and Spectral Response (SR) of solar cells was done in order to suggest ways in which related parameters could be optimized for maximum conversion efficiency of solar cells. Secondary data for the base, emitter and total parameters of QE and SR were obtained. MATLAB was employed in plotting and analysing these data across different diffusion lengths. From the results obtained, it was observed that when the value of the Emitter Diffusion Length (EDL) was varied from 0.3μm to 0.5μm, the emitter and total values of QE increased by about 700% at wavelength 300nm – 400nm. In the case of SR, it was observed that when there was an increase in the Base Diffusion Length (BDL) from 20μm to 50μm, there was an increase of about 26% at wavelength 800nm – 900nm. A rise in the diffusion length was seen to increase both the QE and SR of the cell. Thus, it can be suggested that an increase in the emitter and base diffusion length of a solar cell leads to a decrease in the recombination charges in the cell, giving more time for the charge carriers to exit the cell.
Recyclable Ag-Au bimetallic nanoparticles supported on acid functionalized multi walled carbon nanotubes for effective catalytic applications
Authors: Priya P Vengatesh , Jeyasundari J
Published: May 2024

In the present investigation, in situ green reduction approach is used to uniformly decorate the Ag-Au bimetallic nanoparticles (BNPs) on the surface of acid functionalised multi-walled carbon nanotubes (MWCNTs). The adsorbed Terminalia catappa aqueous leaf extract biopolymers on the surface of MWCNTs can increase the in situ reduction of Ag, Au ions to Ag-Au BNPs and stabilise them which can operate as a capper/stabiliser and reductant agent. X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), scanning electron microscopy - energy dispersive x-ray spectroscopy (SEM-EDX), Fourier-transform infrared spectroscopy (FT-IR) and UV–visible spectroscopy techniques were employed to examine the structures, morphologies, composition, chemical bonds and optical properties of the functionalised MWCNTs and the nanohybrid. The results revealed that the spherical T.C-Ag-Au bimetallic nanoparticle with average size 12.4 nm was uniformly distributed on the surface of modified MWCNTs. Finally, evaluation of the catalytic activity of the T.C-Ag-Au BNPs decorated MWCNTs exhibited excellent catalytic performance for completing the reduction of 4-Nitrophenol (4-NP) and degradation of alizarin red (AR) dye at ambient temperature with a great rate constant and the degradation efficiency of 98.7% and 96.4%, respectively. The order of reaction, rate constant, half-life and mechanism of catalytic activity of the T.C-Ag-Au BNPs@COOH-MWCNTs nanohybrid were calculated using the Langmuir–Hinshelwood model. The catalyst can be retained and reapplied eight times without affecting its catalytic performance. The interaction between T.C-Ag-Au BNPs and MWCNTs has a synergistic effect, which is accountable for the enhanced catalytic activity.
Effect of stabilization and carbonization treatment on the chemical and physical transformation of polyacrylonitrile (PAN) based electrospun carbon nanofibers
Authors: Singcharoen Krittiya , Rangkupan Ratthapol , Khuntong Soontree , Wasanapiarnpong Thanakorn
Published: May 2024

The present study delves into the production of carbon nanofibers (CNFs) utilising electrospun polyacrylonitrile (PAN) nanofiber mats, with a specific focus on the influence of oxidative stabilisation and carbonisation treatments. This research aims to thoroughly understand how variations in stabilisation time and temperature, as well as carbonisation temperature, impact the CNFs properties. These properties include fiber size, morphology, chemical and crystal structure transformation, thermal behaviour, and surface characteristics. Our methodology involved a detailed examination of the thermal treatment processes, where we observed a significant decrease in fiber size, though the surface morphology of the fibers remained largely unaffected. We employed Fourier-transform infrared (FTIR) spectroscopy to track the transformation of nitrile groups in PAN to imine groups, which indicated the progression of cyclisation reactions. Complementary analyses through differential scanning calorimetry (DSC) confirmed a high degree of these reactions, particularly at stabilisation temperatures extending to 250 °C and beyond. The cyclisation process was found to be complete during the carbonisation phase, at temperatures reaching 450 °C and above. Further, x-ray diffraction (XRD) patterns offered insight into the changes in the crystal structure, particularly in the packing of the d(002) spacing because of the stabilisation and carbonisation processes. This findings from this study not only elucidate the intricate process of CNFs production from electrospun PAN nanofiber mats but also highlight the critical factors that influence their final properties. These insights are invaluable for the development of advanced CNFs with tailored properties suitable for a range of applications, including but not limited to energy storage, electronics, and as supporting materials in various technological domains.
Simulation of stress in a blood vessel due to plaque sediments in coronary artery disease
Authors: Rakibuzzaman Md , Kim Hyoung-Ho , Suh Sang-Ho , Lee Byoung-Kwon , Kwon Hyuck Moon , Zhou Ling
Published: May 2024

Atherosclerosis is a cardiovascular disease mainly caused by plaque deposition in blood vessels. Plaque comprises components such as thrombosis, fibrin, collagen, and lipid core. It plays an essential role in inducing rupture in a blood vessel. Generally, Plaque could be described as three kinds of elastic models: cellular Plaque, hypocellular Plaque, and calcified Plaque. The present study aimed to investigate the behavior of atherosclerotic plaque rupture according to different lipid cores using Fluid-Structure Interaction (FSI). The blood vessel was also varied with different thicknesses (0.05, 0.25, and 0.5 mm). In this study, FSI simulation with a cellular plaque model with various thicknesses was investigated to obtain information on plaque rupture. Results revealed that the blood vessel with Plaque having a lipid core represents higher stresses than those without a lipid core. Blood vessels’ thin thickness, like a thin cap, results in more considerable than Von Mises stress. The result also suggests that even at low fracture stress, the risk of rupture due to platelet decomposition at the gap was more significant for cellular plaques.
Thermodynamic stability and vibrational properties of multi-alkali antimonides
Authors: Santana-Andreo Julia , Saßnick Holger-Dietrich , Cocchi Caterina
Published: May 2024

Modern advances in generating ultrabright electron beams have unlocked unprecedented experimental advances based on synchrotron radiation. Current challenges lie in improving the quality of electron sources with novel photocathode materials such as alkali-based semiconductors. To unleash their potential, a detailed characterization and prediction of their fundamental properties is essential. In this work, we employ density functional theory combined with machine learning techniques integrated into thehiphivepackage to probe the thermodynamic stability of various alkali antimonide crystals, emphasizing the role of the approximations taken for the exchange-correlation potential. Our results reveal that the SCAN functional offers an optimal trade-off between accuracy and computational costs to describe the vibrational properties of these materials. Furthermore, it is found that systems with a higher concentration of Cs atoms exhibit enhanced anharmonicities, which are accurately predicted and characterized with the employed methodology.
Symbolic regression as a feature engineering method for machine and deep learning regression tasks
Authors: Shmuel Assaf , Glickman Oren , Lazebnik Teddy
Published: May 2024

In the realm of machine and deep learning (DL) regression tasks, the role of effective feature engineering (FE) is pivotal in enhancing model performance. Traditional approaches of FE often rely on domain expertise to manually design features for machine learning (ML) models. In the context of DL models, the FE is embedded in the neural network’s architecture, making it hard for interpretation. In this study, we propose to integrate symbolic regression (SR) as an FE process before a ML model to improve its performance. We show, through extensive experimentation on synthetic and 21 real-world datasets, that the incorporation of SR-derived features significantly enhances the predictive capabilities of both machine and DL regression models with 34%–86% root mean square error (RMSE) improvement in synthetic datasets and 4%–11.5% improvement in real-world datasets. In an additional realistic use case, we show the proposed method improves the ML performance in predicting superconducting critical temperatures based on Eliashberg theory by more than 20% in terms of RMSE. These results outline the potential of SR as an FE component in data-driven models, improving them in terms of performance and interpretability.
Responsiveness of the condition-specific Outcome measures for VAscular MAlformations (OVAMA) questionnaire to measure symptoms and appearance in patients with vascular malformations
Authors: Stor Merel L E , Lokhorst Max M , Horbach Sophie E R , Luijten Michiel A J , Spuls Phyllis I , van der Horst Chantal M AM
Published: May 2024

Background

Evidence-based guidelines for the treatment of vascular malformations (VMs) are not readily available, possibly due to the diversity in methods used to evaluate treatment efficacy in clinical research, complicating the aggregation and comparison of study results. The Outcome measures for VAscular MAlformations (OVAMA) questionnaire was developed to measure uniformly symptoms and appearance (i.e. condition-specific core outcome domains) in patients with VMs. However, the OVAMA questionnaire needs to be responsive to changes in these constructs in order to assess whether disease status has changed since treatment.

Objectives

To assess the responsiveness of the OVAMA questionnaire in patients with VMs.

Methods

In a prospective longitudinal study, patients completed the OVAMA questionnaire at baseline and at 8 weeks after treatment or a watchful waiting policy. Additionally, patients completed global rating of change (GRC) scales at follow-up. Responsiveness was evaluated following the criterion approach of testing predefined hypotheses about expected relationships between the OVAMA questionnaire and GRC scales measuring the same constructs. The OVAMA questionnaire was considered responsive if ≥ 75% of the hypotheses were confirmed.

Results

Between July 2020 and September 2022, 89 patients were recruited in a vascular anomaly centre in the Netherlands; 63 patients completed the questionnaires at baseline and follow-up. In total, 15 constructs of the OVAMA questionnaire were assessed for 5 hypotheses. Of these 75 hypotheses, 63 (84%) were confirmed, providing evidence that the OVAMA questionnaire is responsive to change.

Conclusion

Our study found convincing evidence that the OVAMA questionnaire is responsive to changes in symptoms and appearance in patients with VMs. In addition to determining a baseline for symptoms and appearance, the OVAMA questionnaire can now be used to evaluate the effect of treatment from a patient’s perspective. The responsive OVAMA questionnaire allows for uniform evaluation and comparison of the effects of treatment on the condition-specific core outcome domains, tackling heterogeneity in outcome measurement and improving the clinical research of VMs.
Macroscopic changes in aquaporin-4 underlie blast traumatic brain injury-related impairment in glymphatic function
Authors: Braun Molly , Sevao Mathew , Keil Samantha A , Gino Elizabeth , Wang Marie X , Lee Janet , Haveliwala Mariya A , Klein Emily , Agarwal Sanjana , Pedersen Taylor , Rhodes C Harker , Jansson Deidre , Cook David , Peskind Elaine , Perl Daniel P , Piantino Juan , Schindler Abigail G , Iliff Jeffrey J
Published: May 2024

Mild traumatic brain injury (mTBI) has emerged as a potential risk factor for the development of neurodegenerative conditions such as Alzheimer’s disease and chronic traumatic encephalopathy. Blast mTBI, caused by exposure to a pressure wave from an explosion, is predominantly experienced by military personnel and has increased in prevalence and severity in recent decades. Yet the underlying pathology of blast mTBI is largely unknown.

We examined the expression and localization of AQP4 in human post-mortem frontal cortex and observed distinct laminar differences in AQP4 expression following blast exposure. We also observed similar laminar changes in AQP4 expression and localization and delayed impairment of glymphatic function that emerged 28 days following blast injury in a mouse model of repetitive blast mTBI. In a cohort of veterans with blast mTBI, we observed that blast exposure was associated with an increased burden of frontal cortical MRI-visible perivascular spaces, a putative neuroimaging marker of glymphatic perivascular dysfunction.

These findings suggest that changes in AQP4 and delayed glymphatic impairment following blast injury may render the post-traumatic brain vulnerable to post-concussive symptoms and chronic neurodegeneration.
Development of Next-Generation COVID-19 Vaccines: Biomedical Advanced Research and Development Authority (BARDA­)–Supported Phase 2b Study Designs
Authors: Wolfe Daniel N , Arangies Elizabeth , David Gloria L , Armstrong Brian , Scocca Theresa Z , Fedler Janel , Natarajan Ramya , Zhou James , Jayashankar Lakshmi , Donis Ruben , Nesin Mirjana , Meissner H Cody , Lemiale Laurence , Kovacs Gerald R , Rele Shyam , Mason Robin , Cao Huyen
Published: May 2024

In response to the coronavirus disease 2019 (COVID-19) pandemic, vaccines were quickly and successfully developed and deployed, saving millions of lives globally. While first-generation vaccines are safe and effective in preventing disease caused by SARS-CoV-2, next-generation vaccines have the potential to improve efficacy and safety. Vaccines delivered by a mucosal route may elicit greater protective immunity at respiratory surfaces, thereby reducing transmission. Inclusion of viral antigens in addition to the spike protein may enhance protection against emerging variants of concern. Next-generation vaccine platforms with a new mechanism of action may necessitate efficacy trials to fulfill regulatory requirements. The Biomedical Advanced Research and Development Authority (BARDA) will be supporting Phase 2b clinical trials of candidate next-generation vaccines. The primary endpoint will be improved efficacy in terms of symptomatic disease relative to a currently approved COVID-19 vaccine. In this paper, we discuss the planned endpoints and potential challenges to this complex program.
Tenofovir Alafenamide Versus Tenofovir Disoproxil Fumarate for Preventing Vertical Transmission in Chronic Hepatitis B Mothers: A Systematic Review and Meta-Analysis
Authors: Pan Calvin Q , Zhu Lin , Yu Andy S , Zhao Yuchan , Zhu Bo , Dai Erhei
Published: May 2024

Objective

International guidelines recommend maternal tenofovir disoproxil fumarate (TDF) therapy accompanied by infant immunoprophylaxis to prevent hepatitis B virus (HBV) mother-to-child transmission (MTCT) in highly viremic mothers. However, pooled analyses for tenofovir alafenamide (TAF) effects and comparisons between the 2 regimens are lacking.

Design

In this meta-analysis, pairs of independent reviewers performed multiple database searches from inception to 31 March 2024 and extracted data from cohort studies and randomized controlled trials (RCTs) in highly viremic mothers. The outcomes of interest were the reduction of MTCT and safety in the TDF-treated, TAF-treated, and control groups.

Results

We included 31 studies with 2588 highly viremic mothers receiving TDF, 280 receiving TAF, and 1600 receiving no treatment. Compared to the control, TDF therapy reduced the MTCT rate in infants aged 6–12 months (risk ratio: 0.10, 95% confidence interval [CI] .07–.16). Pairwise meta-analysis between TAF and TDF revealed similar effects on reducing MTCT (risk ratio: 1.09, 95% confidence interval .16–7.61). Network meta-analysis showed equal efficacy of the 2 regimens in reducing MTCT (risk ratio: 1.09, 95% CI .15–7.65). The surface under the cumulative ranking curve revealed TDF as the best regimen compared with TAF (probability ranking: .77 vs .72), while receiving a placebo during pregnancy had the lowest efficacy (probability ranking 0.01). There were no safety concerns for mothers and infants in all regimens.

Conclusions

Compared to placebo or no treatment, maternal TDF and TAF prophylaxis are equally effective and without safety concerns in reducing MTCT in highly viremic mothers.
Linear clustering process on networks: a comparative study
Authors: Jokić Ivan , Wang Beichen , Van Mieghem Piet
Published: May 2024

By a thorough performance comparison, we compare the recently proposed, operator-based linear clustering process on a network with classical, existing clustering algorithms. The linear clustering process produces clusters or partitions based on the eigenstructure of a linear operator on a graph that replaces nodes to ‘more natural’ positions by attractive and repulsive forces. Synthetic benchmarks, along with real-world networks possessing or lacking a known community structure, are considered. Our comparative analysis demonstrates that our linear clustering process generates superior partitions compared to the algorithms assessed in most instances, while of comparable computational complexity with the simplest existing clustering algorithms.
MechanoBase: a comprehensive database for the mechanics of tissues and cells
Authors: Xiong Yanhong , Li Shiyu , Zhang Yuxuan , Chen Qianqian , Xing Mengtan , Zhang Yong , Wang Qi
Published: May 2024

Mechanical aspects of tissues and cells critically influence a myriad of biological processes and can substantially alter the course of diverse diseases. The emergence of diverse methodologies adapted from physical science now permits the precise quantification of the cellular forces and the mechanical properties of tissues and cells. Despite the rising interest in tissue and cellular mechanics across fields like biology, bioengineering and medicine, there remains a noticeable absence of a comprehensive and readily accessible repository of this pertinent information. To fill this gap, we present MechanoBase, a comprehensive tissue and cellular mechanics database, curating 57 480 records from 5634 PubMed articles. The records archived in MechanoBase encompass a range of mechanical properties and forces, such as modulus and tractions, which have been measured utilizing various technical approaches. These measurements span hundreds of biosamples across more than 400 species studied under diverse conditions. Aiming for broad applicability, we design MechanoBase with user-friendly search, browsing and data download features, making it a versatile tool for exploring biomechanical attributes in various biological contexts. Moreover, we add complementary resources, including the principles of popular techniques, the concepts of mechanobiology terms and the cellular and tissue-level expression of related genes, offering scientists unprecedented access to a wealth of knowledge in this field of research.

Database URL: https://zhanglab-web.tongji.edu.cn/mechanobase/ and https://compbio-zhanglab.org/mechanobase/
Judicial Decisions, Backlash and Secessionism: The Spanish Constitutional Court and Catalonia
Authors: Casas Agustin , Curci Federico , De Moragas Antoni-Italo
Published: May 2024

We exploit a unique quasi-experiment to study the effects of judicial decisions on sensitive issues on political attitudes. In 2010, the Spanish Constitutional Court partially overruled the new Catalan Constitution—the Estatut—that granted further decentralisation. Our identification strategy relies on the fact that this ruling occurred amid a public opinion survey. We find that the ruling increased support for independence by 5 percentage points. We interpret this result as evidence of judicial backlash on political attitudes: a judicial decision that limited further autonomy triggered a shift in attitudes towards even more autonomy. Moreover, the ruling decreased trust in the courts and satisfaction with democracy. This backlash of political attitudes extends to other spheres: Catalans increased their national identification with their region and the support for pro-decentralisation parties. Finally, we show that the ruling increased polarisation around the partisan and identity cleavages.
Platelet-fibrin clot strength and platelet reactivity predicting cardiovascular events after percutaneous coronary interventions
Authors: Kwon Osung , Ahn Jong-Hwa , Koh Jin-Sin , Park Yongwhi , Hwang Seok Jae , Tantry Udaya S , Gurbel Paul A , Hwang Jin-Yong , Jeong Young-Hoon
Published: May 2024

Background and Aims

Platelet-fibrin clot strength (PFCS) is linked to major adverse cardiovascular event (MACE) risk. However, the association between PFCS and platelet reactivity and their prognostic implication remains uncertain in patients undergoing percutaneous coronary intervention (PCI).

Methods

In PCI-treated patients (n = 2512) from registry data from January 2010 to November 2018 in South Korea, PFCS using thromboelastography and platelet reactivity using VerifyNow were measured. High PFCS (PFCSHigh) was defined as thromboelastography maximal amplitude ≥ 68 mm, and high platelet reactivity (HPR) was defined as >208 P2Y12 reaction units. Patients were stratified into four groups according to maximal amplitude and P2Y12 reaction unit levels: (i) normal platelet reactivity (NPR)-PFCSNormal (31.8%), (ii) HPR-PFCSNormal (29.0%), (iii) NPR-PFCSHigh (18.1%), and (iv) HPR-PFCSHigh (21.1%). Major adverse cardiovascular event (all-cause death, myocardial infarction, or stroke) and major bleeding were followed up to 4 years.

Results

High platelet reactivity and PFCSHigh showed an additive effect for clinical outcomes (log-rank test, P < .001). Individuals with NPR-PFCSNormal, NPR-PFCSHigh, HPR-PFCSNormal, and HPR-PFCSHigh demonstrated MACE incidences of 7.5%, 12.6%, 13.4%, and 19.3%, respectively. The HPR-PFCSHigh group showed significantly higher risks of MACE compared with the NPR-PFCSNormal group [adjusted hazard ratio (HRadj) 1.89; 95% confidence interval (CI) 1.23–2.91; P = .004] and the HPR-PFCSNormal group (HRadj 1.60; 95% CI 1.12–2.27; P = .009). Similar results were observed for all-cause death. Compared with HPR-PFCSNormal phenotype, NPR-PFCSNormal phenotype was associated with a higher risk of major bleeding (HRadj 3.12; 95% CI 1.30–7.69; P = .010).

Conclusions

In PCI patients, PFCS and platelet reactivity demonstrated important relationships in predicting clinical prognosis. Their combined assessment may enhance post-PCI risk stratification for personalized antithrombotic therapy.
Examining the Effects of Temperature on the Evolution of Bacterial tRNA Pools
Authors: Jain Vatsal , Cope Alexander L
Published: May 2024

The genetic code consists of 61 codons coding for 20 amino acids. These codons are recognized by transfer RNAs (tRNAs) that bind to specific codons during protein synthesis. All organisms utilize less than all 61 possible anticodons due to base pair wobble: the ability to have a mismatch with a codon at its third nucleotide. Previous studies observed a correlation between the tRNA pool of bacteria and the temperature of their respective environments. However, it is unclear if these patterns represent biological adaptations to maintain the efficiency and accuracy of protein synthesis in different environments. A mechanistic mathematical model of mRNA translation is used to quantify the expected elongation rates and error rate for each codon based on an organism's tRNA pool. A comparative analysis across a range of bacteria that accounts for covariance due to shared ancestry is performed to quantify the impact of environmental temperature on the evolution of the tRNA pool. We find that thermophiles generally have more anticodons represented in their tRNA pool than mesophiles or psychrophiles. Based on our model, this increased diversity is expected to lead to increased missense errors. The implications of this for protein evolution in thermophiles are discussed.
A critical review of the reporting of reflexive thematic analysis in Health Promotion International
Authors: Braun Virginia , Clarke Victoria
Published: May 2024

Using the concept of methodological congruence—where the different elements of a study ‘fit’ together—we explore both problematic and good practice in (reflexive) thematic analysis (TA) as reported in Health Promotion International (HPI). Aligning with the importance we place on ‘owning your perspectives’ we situate this exploration in relation to our understanding of the variation in approaches to TA and qualitative research more broadly. This contextualization is necessary for highlighting why we judge practices to be in/congruent, and to facilitate more knowing congruence in future research. We critically reviewed a ‘sample’ of 31 papers published in HPI between 2010 and 2023 citing Braun and Clarke as reference for TA. We overview a range of problematic and good features of the use of TA in HPI, before focusing on two domains that seemed to present key challenges: theory and themes. Methodological incongruence can occur when postpositivist values and practices unwittingly creep into ostensibly non-positivist TA; we encourage thoughtfully and what we term ‘knowing’ consideration of theory, and quality practices and criteria. Methodological incongruence can also occur through mismatched conceptualizations of themes—notably, the use of ‘topic summaries’ as themes for reflexive TA (and fragmented thematic structures with ‘thin’ themes). We provide examples from the reviewed papers to demonstrate good practice in researcher reflexivity, articulation of theoretical and methodological frameworks and congruent themes. However, mindful of power dynamics, we only discuss problematic practice in general terms, to protect author anonymity. To facilitate thoughtful, quality TA—of all kinds—we provide eight pointers for researchers (and reviewers) to guide quality practice, and facilitate the use of concepts, procedures and criteria that promote knowing methodological congruence.
Amphibians Exhibit Extremely High Hydric Costs of Respiration
Authors: Riddell Eric A , Burger Isabella J , Muñoz Martha M , Weaver Savannah J , Womack Molly C
Published: May 2024

Synopsis

Terrestrial environments pose many challenges to organisms, but perhaps one of the greatest is the need to breathe while maintaining water balance. Breathing air requires thin, moist respiratory surfaces, and thus the conditions necessary for gas exchange are also responsible for high rates of water loss that lead to desiccation. Across the diversity of terrestrial life, water loss acts as a universal cost of gas exchange and thus imposes limits on respiration. Amphibians are known for being vulnerable to rapid desiccation, in part because they rely on thin, permeable skin for cutaneous respiration. Yet, we have a limited understanding of the relationship between water loss and gas exchange within and among amphibian species. In this study, we evaluated the hydric costs of respiration in amphibians using the transpiration ratio, which is defined as the ratio of water loss (mol H2O d−1) to gas uptake (mol O2 d−1). A high ratio suggests greater hydric costs relative to the amount of gas uptake. We compared the transpiration ratio of amphibians with that of other terrestrial organisms to determine whether amphibians had greater hydric costs of gas uptake relative to plants, insects, birds, and mammals. We also evaluated the effects of temperature, humidity, and body mass on the transpiration ratio both within and among amphibian species. We found that hydric costs of respiration in amphibians were two to four orders of magnitude higher than the hydric costs of plants, insects, birds, and mammals. We also discovered that larger amphibians had lower hydric costs than smaller amphibians, at both the species- and individual-level. Amphibians also reduced the hydric costs of respiration at warm temperatures, potentially reflecting adaptive strategies to avoid dehydration while also meeting the demands of higher metabolic rates. Our results suggest that cutaneous respiration is an inefficient mode of respiration that produces the highest hydric costs of respiration yet to be measured in terrestrial plants and animals. Yet, amphibians largely avoid these costs by selecting aquatic or moist environments, which may facilitate more independent evolution of water loss and gas exchange.
Period Relations Between the Betti–Whittaker Periods for GLn Under Duality
Authors: Chen Shih-Yu
Published: May 2024

In this paper, under some regularity conditions, we prove a period relation between the Betti–Whittaker periods associated to a regular algebraic cuspidal automorphic representation of $\operatorname{GL}_{n}({{\mathbb{A}}})$ and its contragredient. As a consequence, we prove the trivialness of the relative period associated to a regular algebraic cuspidal automorphic representation of $\operatorname{GL}_{2n}({{\mathbb{A}}})$ of orthogonal type, which implies the algebraicity of the ratios of successive critical $L$-values for $\textrm{GSpin}_{2n}^{*} \times \operatorname{GL}_{n^{\prime}}$ by the result of Harder and Raghuram.
Chronotropic Incompetence Among People With HIV Improves With Exercise Training in the Exercise for Healthy Aging Study
Authors: Durstenfeld Matthew S , Wilson Melissa P , Jankowski Catherine M , Ditzenberger Grace L , Longenecker Chris T , Erlandson Kristine M
Published: May 2024

Background

People with HIV (PWH) have lower exercise capacity than peers without HIV, which may be explained by chronotropic incompetence, the inability to increase heart rate during exercise.

Methods

The Exercise for Healthy Aging Study included adults aged 50 to 75 years with and without HIV. Participants completed 12 weeks of moderate-intensity exercise, before randomization to moderate or high intensity for 12 additional weeks. We compared adjusted heart rate reserve (AHRR; chronotropic incompetence <80%) on cardiopulmonary exercise testing by HIV serostatus and change from baseline to 12 and 24 weeks using mixed effects models.

Results

Among 32 PWH and 37 controls (median age, 56 years; 7% female), 28% of PWH vs 11% of controls had chronotropic incompetence at baseline (P = .067). AHRR was lower among PWH (91% vs 101%; difference, 10%; 95% CI, 1.9%–18.9%; P = .02). At week 12, AHRR normalized among PWH (+8%; 95% CI, 4%–11%; P < .001) and was sustained at week 24 (+5%; 95% CI, 1%–9%; P = .008) versus no change among controls (95% CI, −4% to 4%; P = .95; interaction P = .004). After 24 weeks of exercise, 15% of PWH and 10% of controls had chronotropic incompetence (P = .70).

Conclusions

Chronotropic incompetence contributes to reduced exercise capacity among PWH and improves with exercise training.