bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unit sphere fibrations in Euclidean space
Authors: Asimov Daniel , Frick Florian , Harrison Michael , Pegden Wesley 
Published: March 2024

AbstractWe show that if an open set in $\mathbb{R}^d$ can be fibered by unit n-spheres, then $d \geq 2n+1$, and if $d = 2n+1$, then the spheres must be pairwise linked, and $n \in \left\{0, 1, 3, 7 \right\}$. For these values of n, we construct unit n-sphere fibrations in $\mathbb{R}^{2n+1}$.
Proof of some conjectural congruences involving Apéry and Apéry-like numbers
Authors: Mao Guo-Shuai , Wang Lilong 
Published: March 2024

AbstractIn this paper, we mainly prove the following conjectures of Sun [16]: Let p > 3 be a prime. Then
\begin{align*}
&A_{2p}\equiv A_2-\frac{1648}3p^3B_{p-3}\ ({\rm{mod}}\ p^4),\\
&A_{2p-1}\equiv A_1+\frac{16p^3}3B_{p-3}\ ({\rm{mod}}\ p^4),\\
&A_{3p}\equiv A_3-36738p^3B_{p-3}\ ({\rm{mod}}\ p^4),
\end{align*}where $A_n=\sum_{k=0}^n\binom{n}k^2\binom{n+k}{k}^2$ is the nth Apéry number, and Bn is the nth Bernoulli number.
Nonlinear electron scattering by electrostatic waves in collisionless shocks
Authors: Kamaletdinov Sergei R. , Vasko Ivan Y. , Artemyev Anton V. 
Published: March 2024

We present a theoretical analysis of electron pitch-angle scattering by ion-acoustic electrostatic fluctuations present in the Earth's bow shock and, presumably, collisionless shocks in general. We numerically simulate electron interaction with a single wave packet to demonstrate the scattering through phase bunching and phase trapping and quantify electron pitch-angle scattering in dependence on the wave amplitude and wave normal angle to the local magnetic field. The iterative mapping technique is used to model pitch-angle scattering of electrons by a large number of wave packets, which have been reported in the Earth's bow shock. Assuming that successive electron scatterings are not correlated, we revealed that the long-term dynamics of electrons is diffusive. The diffusion coefficient depends on the ratio

$\varPhi _0/W$

between the wave packet amplitude and electron energy,

$D\propto (\varPhi _0/W)^{\nu }$

. A quasi-linear scaling (

$\nu \approx 2$

) is observed for sufficiently small wave amplitudes,

$\varPhi _0\lesssim 10^{-3}W$

, while the diffusion is nonlinear (

$1<\nu <2$

) above this threshold. We show that pitch-angle diffusion of

${\lesssim }1$

keV electrons in the Earth's bow shock can be nonlinear. The corresponding diffusion coefficient scales with the intensity

$E_{w}^{2}$

of the electrostatic fluctuations in a nonlinear fashion,

$D\propto E_{w}^{\nu }$

with

$\nu <2$

, while its expected values in the Earth's bow shock are

$D\sim 0.1\unicode{x2013}100$

$(T_{e}/W)^{\nu -1/2}\,{\rm rad}^{2}\,{\rm s}^{-1}$

. We speculate that in the Earth's quasi-perpendicular bow shock the stochastic shock drift acceleration mechanism with pitch-angle scattering provided by the electrostatic fluctuations can contribute to the acceleration of thermal electrons up to approximately 1 keV. The potential effects of a finite perpendicular coherence scale of the wave packets on the efficiency of electron scattering are discussed.
Force analysis of a soft-rigid hybrid pneumatic actuator and its application in a bipedal inchworm robot
Authors: Jiang Zhujin , Zhang Ketao 
Published: March 2024

AbstractThis paper systematically investigates a soft-rigid hybrid pneumatic actuator (SRHPA), which consists of a rigid-foldable twisting skeleton capable of a large range of helical motion and a soft bellows muscle with high linear driving force. Considering the unique varying-pitch helical motion of the foldable skeleton, the analytical model mapping the input force generated by the bellows muscle and output forces of the actuator is revealed and verified with a simulation of the force analysis. Prototypes of the actuator are developed by fabricating the twisting skeleton with multilayered aluminum composite panels and 3D-printing the bellows muscle with thermoplastic polyurethane (TPU) 95A filament. The static and dynamic performances of the prototypes are tested to validate the analytical modeling of output forces. Using the actuator as a module, a novel bipedal inchworm robot with four modules is developed and tested to demonstrate its adaptability in confined space by switching between the going-straight, the turning-around, and the rotating gaits. The hybrid actuator and the inchworm robot with zero onboard electronics have the potential to be deployed in extreme environments where pneumatically actuated systems are preferred over electrical machines and drives, such as in nuclear and explosive environments.
Adaptive fractional-order integral fast terminal sliding mode and fault-tolerant control of dual-arm robots
Authors: Tuan Le Anh , Ha Quang Phuc 
Published: March 2024

AbstractClosed-loop kinematics of a dual-arm robot (DAR) often induces motion conflict. Control formulation is increasingly difficult in face of actuator failures. This article presents a new approach for fault-tolerant control of DARs based on advanced sliding mode control. A comprehensive fractional-order model is proposed taking nonlinear viscous and viscoelastic friction at the joints into account. Using integral fast terminal sliding mode control and fractional calculus, we develop two robust controllers for robots subject to motor faults, parametric uncertainties, and disturbances. Their merits rest with their strong robustness, speedy finite-time convergence, shortened reaching phase, and flexible selection of derivative orders. To avoid the need for full knowledge of faults, robot parameters, and disturbances, two versions of the proposed approach, namely adaptive integral fractional-order fast terminal sliding mode control, are developed. Here, an adaptation mechanism is equipped for estimating a common representative of individual uncertainties. Simulation and experiment are provided along with an extensive comparison with existing approaches. The results demonstrate the superiority of the proposed control technique. The robot performs well the tasks with better responses (e.g., with settling time reduced by at least 16%).
Conscience des déficits dans le cadre de la maladie d’Alzheimer : représentations et vécu des professionnels soignants
Authors: Vignolo Julie , Jacus Jean-Pierre , Darnaud Thierry , Cuervo-Lombard Christine Vanessa 
Published: March 2024

RésuméLa qualité des soins apportés aux personnes vivant avec la maladie d’Alzheimer (MA) dépend en partie de la capacité des professionnels à déterminer le degré de conscience de la maladie chez les patients. La présente recherche s’est intéressée aux représentations des soignants concernant la conscience des troubles chez les résidents d’établissements de soins de longue durée présentant un diagnostic de MA. Le pouvoir prédicteur de l’anosognosie sur le fardeau soignant a également été examiné. L’anosognosie des troubles de la construction (r = 0,40, p = 0,0164) et de l’initiation (r = 0,32, p = 0,052) était corrélée au fardeau soignant. Les professionnels se représentaient les résidents comme ayant une conscience altérée de leurs capacités, même en l’absence d’anosognosie. Les scores réels d’anosognosie ne prédisaient pas les estimations soignantes, hormis le score global sous forme de tendance (χ2 = 3,38, p = 0,066). Les soignants surestimaient pourtant les performances cognitives des résidents, telles que mesurées au moyen du protocole Misawareness (prédictions aidants/performances réelles : DC = 12,32, p < 0,0001).
Medical Trainees Abroad: Neglected Human Rights Considerations
Authors: Appel Jacob M. 
Published: March 2024

Abstract
Medical trainees (applicants, students, and house officers) often engage in global health initiatives to enhance their own education through research and patient care. These endeavors may concomitantly prove of value to host nations in filling unmet clinical needs. At present, healthcare institutions generally focus on the safety of the trainee and the welfare of potential patients and research subjects when sanctioning such programs. The American medical community has historically afforded less consideration to the ethics of engagement by trainees from the United States in nations known for serious human rights transgressions. This essay examines the ethics of such endeavors and argues for increased consideration of these broader considerations when trainees engage in global health work abroad.
Improving GNSS PPP Performance in the South China Under Different Weather Conditions by Using the Weather Research and Forecasting (WRF) Model‐Derived Wet Delay Corrections
Authors: Gong Yangzhao , Liu Zhizhao , Yu Shiwei , Chan Pak Wai , Hon Kai Kwong 
Published: March 2024

AbstractAtmospheric wet delay caused by Precipitable Water Vapor (PWV) significantly impacts the performance of many geodetic surveying systems such as Global Navigation Satellite System (GNSS). In this study, we use wet delay corrections forecast by the Weather Research and Forecasting (WRF) model to enhance GNSS Precise Point Positioning (PPP) during two observation periods with two different weather conditions, that is, period 1: March 01 to 14, 2020 (average PWV: 23.5 kg/m2) and period 2: June 02 to 15, 2020 (flooding weather with average PWV: 55.6 kg/m2), over the South China. PWV data from 277 to 263 GNSS stations are assimilated into WRF model to enhance the WRF water vapor forecasting capability for period 1 and period 2, respectively. Wet delay corrections from two different WRF configurations, that is, WRF no data assimilation and WRF with assimilation of GNSS PWV, are used to augment the PPP. Totally, eight WRF‐enhanced PPP schemes are tested. The results show that WRF‐enhanced PPP schemes generally have a better positioning performance in the up component than traditional PPP. After using WRF wet delay corrections, for static mode, the vertical positioning accuracy is improved by 14.6% and 33.7% for period 1 and period 2, respectively. The corresponding convergence time are reduced by 41.8% and 25.0% for period 1 and period 2, respectively. For kinematic mode, the positioning accuracy improvements in the up component reach 13.8% and 19.0% for period 1 and period 2, respectively. The kinematic PPP convergence time is reduced by up to 8.2% for period 1.
Uncovering the Drivers of Responsive Ionospheric Dynamics to Severe Space Weather Conditions: A Coordinated Multi‐Instrumental Approach
Authors: Calabia Andrés , Imtiaz Nadia , Altadill David , Yasyukevich Yury , Segarra Antoni , Prol Fabricio S. , Adhikari Binod , del Peral Luis , Rodriguez Frias Maria Dolores , Molina Iñigo 
Published: March 2024

AbstractSpace‐weather conditions can often have a detrimental impact on satellite communications and limited experimental data has made it challenging to understand the complex processes that occur in the upper atmosphere. To overcome this challenge, we utilized a coordinated multi‐instrumental dataset consisting of GNSS airglow remote sensing, ionosonde, magnetometer, and in‐situ satellite data to investigate plasma depletions. We present a case study focused on the geomagnetic storm that occurred on 27 February 2014. During the storm, GNSS positioning errors exceeded undisturbed levels by at least 2 times, and ionospheric corrections reached amplitudes of up to ±20 m at the Rabat station. We identified 3 large depletions that were most likely generated by sudden vertical ionospheric drifts that began at approximately 17:00 UTC at sunset in Morocco and the southern regions of Spain. These drifts reached ∼500 m/s and lasted until 22:00 UTC. The observed depletions propagated to the northeast, as seen through ionosonde echoes and ground‐based airglow images. Satellite limb‐images revealed an ionospheric uplift of about 100 km due to the storm, consistent with ionosondes in Spain. The observed local anomalies may be influenced by variations in equatorial electric current flows, which are correlated with fluctuations in ground‐based magnetometer data. These variations are likely a result of the effects of the inner radiation belt on the development of plasma bubbles in the African longitude sector. Sudden enhancements in upward E × B drift caused ionospheric uplift to higher altitudes, enhancing the “fountain effect” and shifting the Equatorial Ionospheric Anomaly crests to higher latitudes.
Parameterizing Mesoscale Eddy Buoyancy Transport Over Sloping Topography
Authors: Nummelin Aleksi , Isachsen Pål Erik 
Published: March 2024

AbstractMost of the ocean's kinetic energy is contained within the mesoscale eddy field. Models that do not resolve these eddies tend to parameterize their impacts such that the parameterized transport of buoyancy and tracers reduces the large‐scale available potential energy and spreads tracers. However, the parameterizations used in the ocean components of current generation Earth System Models rely on an assumption of a flat ocean floor even though observations and high‐resolution modeling show that eddy transport is sensitive to the potential vorticity gradients associated with a sloping seafloor. We show that buoyancy transport coefficient diagnosed from idealized eddy‐resolving simulations is indeed reduced over both prograde and retrograde bottom slopes (topographic wave propagation along or against the mean flow, respectively) and that the reduction can be skilfully captured by a mixing length parameterization by introducing the topographic Rhines scale as a length scale. This modified “GM” parameterization enhances the strength of thermal wind currents over the slopes in coarse‐resolution, non‐eddying, simulations. We find that in realistic global coarse‐resolution simulations the impact of topography is most pronounced at high latitudes, enhancing the mean flow strength and reducing temperature and salinity biases. Reducing the buoyancy transport coefficient further with a mean‐flow dependent eddy efficiency factor, has notable effects also at lower latitudes and leads to reduction of global mean biases.
Weighted burden analysis of rare coding variants in 470,000 exome-sequenced UK Biobank participants characterises effects on hyperlipidaemia risk
Authors: Curtis David 
Published: March 2024

AbstractA previous study of 200,000 exome-sequenced UK Biobank participants investigating the association between rare coding variants and hyperlipidaemia had implicated four genes, LDLR, PCSK9, APOC3 and IFITM5, at exome-wide significance. In addition, a further 43 protein-coding genes were significant with an uncorrected p value of <0.001. Exome sequence data has become available for a further 270,000 participants and weighted burden analysis to test for association with hyperlipidaemia was carried out in this sample for the 47 genes highlighted by the previous study. There was no evidence to implicate IFITM5 but LDLR, PCSK9, APOC3, ANGPTL3, ABCG5 and NPC1L1 were all statistically significant after correction for multiple testing. These six genes were also all exome-wide significant in the combined sample of 470,000 participants. Variants impairing function of LDLR and ABCG5 were associated with increased risk whereas variants in the other genes were protective. Variant categories associated with large effect sizes are cumulatively very rare and the main benefit of this kind of study seems to be to throw light on the molecular mechanisms impacting hyperlipidaemia risk, hopefully supporting attempts to develop improved therapies.
Functional characterization of cooperating MGA mutations in RUNX1::RUNX1T1 acute myeloid leukemia
Authors: Thomas Melvin E. , Qi Wenqing , Walsh Michael P. , Ma Jing , Westover Tamara , Abdelhamed Sherif , Ezzell Lauren J. , Rolle Chandra , Xiong Emily , Rosikiewicz Wojciech , Xu Beisi , Loughran Allister J. , Pruett-Miller Shondra M. , Janke Laura J. , Klco Jeffery M. 
Published: March 2024

AbstractMGA (Max-gene associated) is a dual-specificity transcription factor that negatively regulates MYC-target genes to inhibit proliferation and promote differentiation. Loss-of-function mutations in MGA have been commonly identified in several hematological neoplasms, including acute myeloid leukemia (AML) with RUNX1::RUNX1T1, however, very little is known about the impact of these MGA alterations on normal hematopoiesis or disease progression. We show that representative MGA mutations identified in patient samples abolish protein-protein interactions and transcriptional activity. Using a series of human and mouse model systems, including a newly developed conditional knock-out mouse strain, we demonstrate that loss of MGA results in upregulation of MYC and E2F targets, cell cycle genes, mTOR signaling, and oxidative phosphorylation in normal hematopoietic cells, leading to enhanced proliferation. The loss of MGA induces an open chromatin state at promoters of genes involved in cell cycle and proliferation. RUNX1::RUNX1T1 expression in Mga-deficient murine hematopoietic cells leads to a more aggressive AML with a significantly shortened latency. These data show that MGA regulates multiple pro-proliferative pathways in hematopoietic cells and cooperates with the RUNX1::RUNX1T1 fusion oncoprotein to enhance leukemogenesis.
RIOK3 sustains colorectal cancer cell survival under glucose deprivation via an HSP90α-dependent pathway
Authors: Zhang Nan , Dong Lu , Ning Tingting , Du Feng , Zhao Mengran , Xu Junxuan , Xie Sian , Liu Si , Sun Xiujing , Li Peng , Zhang Shutian , Zhu Shengtao 
Published: March 2024

AbstractGlucose oxidation via the pentose phosphate pathway serves as the primary cellular mechanism for generating nicotinamide adenine dinucleotide phosphate (NADPH). The central regions of solid tumors typically experience glucose deficiency, emphasizing the need for sustained NADPH production crucial to tumor cell survival. This study highlights the crucial role of RIOK3 in maintaining NADPH production and colorectal cancer (CRC) cell survival during glucose deficiency. Our findings revealed upregulated RIOK3 expression upon glucose deprivation, with RIOK3 knockout significantly reducing cancer cell survival. Mechanistically, RIOK3 interacts with heat shock protein 90α (HSP90α), a chaperone integral to various cellular processes, thereby facilitating HSP90α binding to isocitrate dehydrogenase 1 (IDH1). This interaction further upregulates IDH1 expression, enhancing NADPH production and preserving redox balance. Furthermore, RIOK3 inhibition had no discernible effect on intracellular NADPH levels and cell death rates in HSP90α-knockdown cells. Collectively, our findings suggest that RIOK3 sustains colon cancer cell survival in low-glucose environments through an HSP90α-dependent pathway. This highlights the significance of the RIOK3–HSP90α–IDH1 cascade, providing insights into potential targeted therapeutic strategies for CRC in metabolic stress conditions.
The interrelationship between pain, life satisfaction and mental health in adults with traumatic spinal cord injury, in the context of a developing country
Authors: Williams Tammy-Lee , Joseph Conran , Nilsson-Wikmar Lena , Phillips Joliana 
Published: March 2024

Abstract
Study design
Cross-sectional, analytical study design using a conveneient sampling strategy.

Objectives
To examine the interrelationship between pain, life satisfaction and indices of negative mental well-being amongst the traumatic spinal cord injury (TSCI) population.

Setting
Western Cape Rehabilitation Center in Cape Town, South Africa.

Methods
Participants (n = 70) were adults (mean age of 36.3, SD = 9.2) with TSCI. Participants completed the following instruments: 10 satisfaction items from the World Health Organization Quality of Life Brief Version, short forms of the Center for Epidemiological Studies Depression Scale and the trait scale of the State-Trait Anxiety Inventory, a one-item measure of pain intensity taken from the International Spinal Cord Injury Pain Basic Data Set and the interference scale of the Brief Pain Inventory.

Results
Correlational analysis (Pearson r) demonstrated that all the indices of mental well-being as well as the two indices of pain was significantly negatively related to life satisfaction. In addition, life satisfaction mediated the relationship between pain intensity and depression as well as anxiety. Life satisfaction only mediated the relationship between pain interference and depression but not anxiety.

Conclusions
An improvement in life satisfaction may lead to improvements in pain interference, pain intensity as well as psychological distress, amongst persons suffering from TSCI Future research should focus on assessing measures/treatment which may improve life satisfaction in the TSCI population.
B cell memory: from generation to reactivation: a multipronged defense wall against pathogens
Authors: Syeda Madiha Zahra , Hong Tu , Huang Chunming , Huang Wenhua , Mu Qingchun 
Published: March 2024

AbstractDevelopment of B cell memory is a conundrum that scientists are still exploring. Studies have been conducted in vitro and using advanced animal models to elucidate the mechanism underlying the generation of memory B cells (MBCs), the precise roles of MBCs against pathogens, and their protective functions against repeated infections throughout life. Lifelong immunity against invading diseases is mainly the result of overcoming a single infection. This protection is largely mediated by the two main components of B cell memory—MBCs and long-lived plasma cells (PCs). The chemical and cellular mechanisms that encourage fat selection for MBCs or long-lived PCs are an area of active research. Despite the fact that nearly all available vaccinations rely on the capacity to elicit B-cell memory, we have yet to develop successful vaccines that can induce broad-scale protective MBCs against some of the deadliest diseases, including malaria and AIDS. A deeper understanding of the specific cellular and molecular pathways that govern the generation, function, and reactivation of MBCs is critical for overcoming the challenges associated with vaccine development. Here, we reviewed literature on the development of MBCs and their reactivation, interaction with other cell types, strategies against invading pathogens, and function throughout life and discussed the recent advances regarding the key signals and transcription factors which regulate B cell memory and their relevance to the quest for vaccine development.
RHBDL4-triggered downregulation of COPII adaptor protein TMED7 suppresses TLR4-mediated inflammatory signaling
Authors: Knopf Julia D. , Steigleder Susanne S. , Korn Friederike , Kühnle Nathalie , Badenes Marina , Tauber Marina , Theobald Sebastian J. , Rybniker Jan , Adrain Colin , Lemberg Marius K. 
Published: March 2024

AbstractThe toll-like receptor 4 (TLR4) is a central regulator of innate immunity that primarily recognizes bacterial lipopolysaccharide cell wall constituents to trigger cytokine secretion. We identify the intramembrane protease RHBDL4 as a negative regulator of TLR4 signaling. We show that RHBDL4 triggers degradation of TLR4’s trafficking factor TMED7. This counteracts TLR4 transport to the cell surface. Notably, TLR4 activation mediates transcriptional upregulation of RHBDL4 thereby inducing a negative feedback loop to reduce TLR4 trafficking to the plasma membrane. This secretory cargo tuning mechanism prevents the over-activation of TLR4-dependent signaling in an in vitro Mycobacterium tuberculosis macrophage infection model and consequently alleviates septic shock in a mouse model. A hypomorphic RHBDL4 mutation linked to Kawasaki syndrome, an ill-defined inflammatory disorder in children, further supports the pathophysiological relevance of our findings. In this work, we identify an RHBDL4-mediated axis that acts as a rheostat to prevent over-activation of the TLR4 pathway.