cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The Pattern of Medical Admissions at the Intensive Care Unit of the University of Port Harcourt Teaching Hospital, Nigeria
Creators: name: Gogo, Otokwala
name: Romokere, Akpa
name: Oluchi, Stanley
Publisher: name: Nigerian Medical Journal
Year: 2025

description: Background: Intensive care units offer specialized care to critically ill patients and are an integral part of modern health care. In low-income countries, with limited resources, the demand to optimize patient care and improve outcomes depends on a better understanding of the pattern of medical referrals to the ICU for varying reasons of resource allocation, staffing, and quality improvement initiatives. This study aims to describe and provide valuable insights into the patterns of medical admissions to the intensive care unit (ICU), including case mixes, intensive care interventions, duration of stay, and outcomes to highlight the need for proper resource allocation

 

Methodology: A retrospective descriptive study was conducted at the University of Port Harcourt Teaching Hospital ICU between January 2022 and December 2024. We reviewed all patients from the Department of Internal Medicine referred to the ICU with a purely medical diagnosis. Data were retrieved from the ICU admissions register and patients' medical records following ethical exemption approval.

 

Results: A total of 377 patients with medical referrals were reviewed, accounting for approximately 56.9% of all ICU admissions. More males were admitted, and the mean age of patients was 48.6 ± 15.3 years. The emergency unit was the commonest source of referral and offered a significant source of in hospital delays prior to transfer to the ICU. The most common indication for ICU admission was stroke, with hemorrhagic stroke, sepsis, and cardiogenic shock associated with the worst outcomes.

 

Conclusion: Stroke predominated medical referrals and provided the worst outcome. The in-hospital delays at the emergency unit which became the largest source of referral contributed to the high mortality. This study highlights the need to strengthen stroke care at the tertiary level of care as well as other medical referrals to improve care.
description: Nigerian Medical Journal, Vol. 66 No. 1 (2025): January - February
An Opinion Dynamics Model for the Diffusion of Innovations
Creators: name: Martins, Andre C. R.
name: Pereira, Carlos de B.
name: Vicente, Renato
Publisher: name: arXiv
Year: 2008
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences

description: We study the dynamics of the adoption of new products by agents with continuous opinions and discrete actions (CODA). The model is such that the refusal in adopting a new idea or product is increasingly weighted by neighbor agents as evidence against the product. Under these rules, we study the distribution of adoption times and the final proportion of adopters in the population. We compare the cases where initial adopters are clustered to the case where they are randomly scattered around the social network and investigate small world effects on the final proportion of adopters. The model predicts a fat tailed distribution for late adopters which is verified by empirical data.
description: 14 pages, 8 figures, revised text, a new section with empirical evidence has been added
March: Battery Energy Storage Systems
Creators: Deepak Krishnan
Harsh Thacker
and Sandhya Sundararagavan
Vigna Kumaran ramachandaramurthy
and Gopinath Subramani
Ram Krishan
and Er. Alekhya	Datta
Ram Krishan
Er. Alekhya Datta
and Ashish Sharma
Publisher: name: IEEE
Year: 2021

Newsletter
Issue on Battery Energy
 Storage Systems featuring "Estimating Energy Storage Requirements for the Tamil Nadu State Grid," "Optimised solar PV-BESS sizing for maximum demand reduction,"Battery Storage and Operational use-cases at the Electricity Distribution Network Level," and "Urban Microgrids – Plethora of Opportunity for City DISCOMs,"
Easing the Pain: Lignocaine Spray in Mid-Trimester Amniocentesis – A Randomized Double-Blind, Placebo-Controlled Trial
Creators: name: Sharma, Tanya
name: Gothwal, Meenakshi
name: Sharma, Charu
name: Singh, Pratibha
name: Yadav, Garima
name: Gupta, Manoj
name: Jhirwal, Manisha
name: Kathuria, Priyanka
Publisher: name: Nigerian Medical Journal
Year: 2025

description: Background: To evaluate the effect of lignocaine spray on maternal pain perception during mid-trimester amniocentesis compared to placebo.

 

Methodology: This was a double-blinded, prospective, randomized controlled trial conducted at a tertiary teaching hospital in Western Rajasthan. Singleton pregnancies between 15- and 24-weeks’ gestation undergoing amniocentesis were included. Participants were randomly assigned to receive either lignocaine spray or placebo (normal saline). Pain was assessed using the Visual Analogue Scale (VAS), Verbal Rating Scale (VRS), and Numerical Rating Scale (NRS). A total of 138 women were enrolled, with 69 receiving lignocaine spray and 69 receiving placebos.

 

Results: Pain perception measured by VAS showed no significant difference between the lignocaine and placebo groups (p = 0.412). VRS and VAS demonstrated a positive correlation (r = 0.692, p < 0.001). Median VAS scores at 30 minutes post-procedure were significantly lower in the lignocaine group (p = 0.008). The Kappa agreement between VAS and VRS was found to be 59.20%. No significant difference in procedure-related complications was observed between groups.

 

Conclusion: The study demonstrates no significant difference in VAS scores or secondary outcomes between the lignocaine and placebo groups, suggesting that lignocaine spray may not provide additional benefit for pain relief in amniocentesis.
description: Nigerian Medical Journal, Vol. 66 No. 1 (2025): January - February
Updated Studies on Exomoons in the HD 23079 System
Creators: name: Jagtap, Oshina
name: Quarles, Billy
name: Cuntz, Manfred
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We re-evaluate the outer edge of orbital stability for possible exomoons orbiting the radial velocity planet discovered in the HD 23079 system. In this system, a solar-type star hosts a Jupiter-mass planet in a nearly circular orbit in the outer stellar habitable zone. The outer stability limit of exomoons is deduced using $N$-body and tidal migration simulations considering a large range of initial conditions, encompassing both prograde and retrograde orbits. In particular, we extend previous works by evaluating many values in the satellite mean anomaly to identify and exclude regions of quasi-stability. Future observations of this system can make use of our results through a scale factor relative to the currently measured minimum mass. Using a constant time lag tidal model (Hut 1981), we find that plausible tidal interactions within the system are insufficient to induce significant outward migration toward the theoretical stability limit. While current technologies are incapable of detecting exomoons in this system, we comment on the detectability of putative moons through Doppler monitoring within direct imaging observations in view of future research capacities.
description: 10 pages, 5 figures, 2 tables; accepted for publication in PASA
YouTube und seine Jugendkultur
Creators: name: Nagler, Daniel
Publisher: name: Medienimpulse
Year: 2017

description: Im folgenden Artikel wird untersucht, was die äußerst erfolgreiche Videoplattform YouTube besonders für junge Menschen so attraktiv macht. Dabei soll nachvollziehbar werden, warum der Aspekt der Selbstinszenierung für Jugendliche und junge Erwachsene im Web 2.0 heute nicht mehr wegzudenken ist. Ziel dieser Arbeit ist es, zu verstehen, weshalb Aufmerksamkeit und Anerkennung als Grundbedürfnisse junger Menschen auch in den digitalen Medien elementar sind. Folglich stellt sich die Frage: Warum kann man YouTube als eine Selbstdarstellungs- und Selbstinszenierungsplattform für Jugendliche verstehen? Dabei wird die Annahme vertreten, dass Aufmerksamkeit und Anerkennung als Folge der Selbstinszenierung und als Grundbedürfnis des Menschen vor allem Jugendlichen helfen, ihre Persönlichkeit zu entfalten. Da YouTube den UserInnen Raum zu solcher Entfaltung bietet, kann dieses Portal zweifelsohne als Mutter der erfolgreichsten Videoplattformen unserer Zeit verstanden werden.
description: Medienimpulse, Bd. 55 Nr. 4 (2017): 4/2017 - Kreativität/Ko-Kreativität
Note on bipartite graph tilings
Creators: name: Hladky, Jan
name: Schacht, Mathias
Publisher: name: arXiv
Year: 2008
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: Let s
description: 6 pages, no figures; statement of the main theorem corrected (thanks to Andrzej Czygrinow and Louis DeBiasio); to appear in SIAM Journal on Discrete Mathematics
B-Mode Ultrasound Grading of Cryptogenic Steatotic Liver Disease and Association with the Level of Sun Exposure in Zaria, Nigeria: A Case-Control Study.
Creators: name: Ibinaiye, Philip
name: Egbo, Benjamin
name: Olarinoye-Akorede, Adebanke
name: Igashi, Joseph
name: Baduku, Tokan
name: Usman, Bello
name: Muhammad, Manko
name: Ahmad, Abdurrahman
name: Tabari, Musa
name: Shettima, Mustapha
name: Balogun, Muhammad
name: Saleh, Mohammed
Publisher: name: Nigerian Medical Journal
Year: 2025

description: Background: Cryptogenic Steatotic Liver Disease (CSLD) is a novel subject where the liver has significant steatosis but without a known cause or abnormal cardiometabolic risk factors. Its aetiology and associations with sunlight exposure remain underexplored, particularly in Nigeria. CSLD is a growing public health concern in Nigeria, characterized by its potential progression to severe liver complications such as cirrhosis and liver cancer, posing significant health risks. This study aimed to determine the association between CSLD and the level of sun exposure.

 

Methodology: This case-control study involved 181 healthy subjects with CSLD and an equal number of normal subjects without CSLD as controls. This made for a total number of 362 subjects. They were recruited into the study consecutively as they emerged after clinical, laboratory, and imaging screenings. A liver ultrasound scan was done using a 3.5MHz frequency transducer to screen for the steatotic liver. The severity of liver steatosis was evaluated by ultrasound bright liver scores (BLS). A daily sun exposure score based on our local pattern was calculated using the information from the administered questionnaire. The data were analyzed with GraphPad Prism software version 6.

 

Results: the median (IQR) age of CSLD and control groups were 44.0 (28.5 - 54.0) and 44.0 (30.0 - 55.0) years. Wilcoxon matched pairs signed rank comparison test showed no significant difference in the ages of the two study groups (p = 0.5578), indicating age matching of the study participants. There was a significant association (χ2 = 59.03, df = 18, p< 0.0001) between age and development of CSLD. One hundred and eighty-one study subjects with CSLD comprised 83 (45.8%) males and 98 (54.1%) females.
The median (IQR) values of the control group's sun exposure score differed significantly from those of the CSLD groups (p = 0.0001) for all categories (mild, moderate, severe steatosis). A multivariate logistic regression analysis model, weighted by years of age and sex, revealed that low sunlight exposure is a significant independent risk factor.

 

Conclusion: The study shows that limited sun exposure is significantly associated with developing CSLD among Nigerians in Zaria. There is also a significant independent risk factor.
description: Nigerian Medical Journal, Vol. 66 No. 1 (2025): January - February
Electronic states of multilayer VTe2: quasi-one-dimensional Fermi surface and implications to charge-density waves
Creators: name: Kawakami, T.
name: Sugawara, K.
name: Kato, T.
name: Taguchi, T.
name: Souma, S.
name: Takahashi, T.
name: Sato, T.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We have performed angle-resolved photoemission spectroscopy on epitaxial VTe2 films to elucidate the relationship between the fermiology and charge-density waves (CDW). We found that a two-dimensional triangular pocket in 1 monolayer (ML) VTe2 is converted to a strongly warped quasi-one-dimensional (1D) Fermi surface in the 6ML counterpart, likely associated with the 1T-to-1T' structural phase transition. We also revealed a metallic Fermi edge on the entire Fermi surface in 6ML at low temperature distinct from anisotropic pseudogap in 1ML, signifying a contrast behavior of CDW that is also supported by first-principles band-structure caluculations. The present result points to the importance of simultaneously controlling the structural phase and fermiology to manipulate the CDW properties in ultrathin transition-metal dichalcogenides.
description: To be published in Physical Review B
Let’s unravel the association between renal stones and renal variant vasculature in patients with duplex collecting system: A retrospective single institute study
Creators: name: Bhinder, Khurram
name: Kanwal, Aroosa
name: Farooq, Zenab
name: Wahla, Madiha
name: Khan, Khizer
Publisher: name: Nigerian Medical Journal
Year: 2025

description: Background: Our study aims to explore the association of duplex collecting systems with variable renal vasculature and renal calculi, given the paucity of published data on the subject.

 

Methodology: Between 2020 and 2023, retrospective research on patients with a duplex collecting system detected by CT scans was conducted at the radiology department of Shifa International Hospital. We assessed any gender bias and ascertained the frequency of this unilateral or bilateral duplex system abnormality. Furthermore, in patients who had received post-contrast imaging, the prevalence of renal calculi and varied renal vasculature was evaluated. In individuals with a duplex collecting system, the correlation between renal stones and renal variant vasculature was computed. SPSS version 25 was used to conduct the chi-square test.

 

Results: We retrospectively gathered data on patients with duplex collecting systems that showed only 65 patients. According to our research, bilateral participation is uncommon but the duplex collecting system is not side-specific. According to our statistics, this aberration has been more common in men as compared to women. Only 36 of the 65 patients in total had post-contrast imaging to check for variances in the vasculature. Of the 36 patients with renal vein variations, 11 had renal vein variations and 25 did not have any anatomical variations. Of the 25 individuals who did not have a renal vein variation, 19 did not have calculus, 2 had calculus involving the lower pole, and 4 had calculus involving the upper pole. 8 individuals with renal variations did not have renal calculus, 2 patients had lower pole calculus, and 1 patient had upper pole calculus. A negative uncertainty coefficient was seen between renal vein vasculature and calculus formation. 17 of the 36 patients had renal artery variations, whereas 19 patients had no anatomic variation of the renal artery. 12 of the 19 individuals without a renal artery variation had no calculus, 2 had calculus involving the lower pole, and 5 had calculus involving the upper pole. 2 individuals had calculus affecting the lower pole, 0 patients had calculus on the upper pole, and 15 patients with renal artery variations had no renal calculus. A positive uncertainty coefficient was seen between renal arterial vasculature and calculus formation.

 

Conclusion: Understanding renal vasculature patterns is vital for effective vascular interventions as well as kidney transplantations. Patients with a duplex collecting system are at increased risk of stasis, infections, and stone formation. For urologists and nephrologists, awareness of the association with variant renal vasculature is critical for managing complications related to this anomaly.
description: Nigerian Medical Journal, Vol. 66 No. 1 (2025): January - February
DEEPAGÉ: Answering Questions in Portuguese about the Brazilian Environment
Creators: name: Cação, Flávio Nakasato
name: José, Marcos Menon
name: Oliveira, André Seidel
name: Spindola, Stefano
name: Costa, Anna Helena Reali
name: Cozman, Fábio Gagliardi
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computation and Language (cs.CL)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: The challenge of climate change and biome conservation is one of the most pressing issues of our time - particularly in Brazil, where key environmental reserves are located. Given the availability of large textual databases on ecological themes, it is natural to resort to question answering (QA) systems to increase social awareness and understanding about these topics. In this work, we introduce multiple QA systems that combine in novel ways the BM25 algorithm, a sparse retrieval technique, with PTT5, a pre-trained state-of-the-art language model. Our QA systems focus on the Portuguese language, thus offering resources not found elsewhere in the literature. As training data, we collected questions from open-domain datasets, as well as content from the Portuguese Wikipedia and news from the press. We thus contribute with innovative architectures and novel applications, attaining an F1-score of 36.2 with our best model.
description: Accepted at BRACIS 2021
Supplementary Material from Viscoelastic differences between isolated and live MCF7 cancer cell nuclei resolved with AFM microrheology
Creators: name: Juel Pørtner, Ellen
name: Mularski, Anna
name: William Jarrett, Tobias
name: Lauritzen Sonder, Stine
name: Nylandsted, Jesper
name: Simonsen, Adam Cohen
Publisher: name: The Royal Society
Year: 2025
Subjects: classificationCode: 310908
subject: Animal physiology - biophysics
classificationCode: 320802
subject: Human biophysics

description: rsif-2024-0885_Supplementary_Revision2.tex_Diff.pdf
A method to calculate correlation functions for $β=1$ random matrices of odd size
Creators: name: Forrester, Peter J.
name: Mays, Anthony
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The calculation of correlation functions for $β=1$ random matrix ensembles, which can be carried out using Pfaffians, has the peculiar feature of requiring a separate calculation depending on the parity of the matrix size N. This same complication is present in the calculation of the correlations for the Ginibre Orthogonal Ensemble of real Gaussian matrices. In fact the methods used to compute the $β=1$, N odd, correlations break down in the case of N odd real Ginibre matrices, necessitating a new approach to both problems. The new approach taken in this work is to deduce the $β=1$, N odd correlations as limiting cases of their N even counterparts, when one of the particles is removed towards infinity. This method is shown to yield the correlations for N odd real Gaussian matrices.
description: 20 pages, corrected typos
Toy model of harmonic and sum frequency generation in 2D nanostructures
Creators: name: Xu, Jie
name: Savinov, Vassili
name: Plum, Eric
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Optical nonlinearities of matter are often associated with the response of individual atoms. Here, using a toy oscillator model, we show that in the confined geometry of a two-dimensional dielectric nanoparticle a collective nonlinear response of the atomic array can arise from the Coulomb interactions of the bound optical electrons, even if the individual atoms exhibit no nonlinearity. We determine the multipole contributions to the nonlinear response of nanoparticles and demonstrate that the odd order and even order nonlinear electric dipole moments scale with the area and perimeter of the nanoparticle, respectively.
description: 14 pages, 10 figures
Experimental details and controls from Viscoelastic differences between isolated and live MCF7 cancer cell nuclei resolved with AFM microrheology
Creators: name: Juel Pørtner, Ellen
name: Mularski, Anna
name: William Jarrett, Tobias
name: Lauritzen Sonder, Stine
name: Nylandsted, Jesper
name: Simonsen, Adam Cohen
Publisher: name: The Royal Society
Year: 2025
Subjects: classificationCode: 310908
subject: Animal physiology - biophysics
classificationCode: 320802
subject: Human biophysics

description: Details on the how the correction for hydrodynamic drag on the cantilever from the surrounding fluid was performed. Mathematical details of the viscoelastic models employed in the data analysis. Control experiments for cell viability after Cytochalasin D treatment. Test to modify the stiffness os isolated nuclei by exposure to Ca2+ or Mg2+ ions.
Comparison of the measured atmospheric muon rate with Monte Carlo simulations and sensitivity study for detection of prompt atmospheric muons with KM3NeT
Creators: name: Kalaczyński, Piotr
Publisher: name: arXiv
Year: 2021
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: The KM3NeT Collaboration has successfully deployed the first detection units of the next generation undersea neutrino telescopes in the Mediterranean Sea at the two sites in Italy and in France. A sample of the data collected between December 2016 and January 2020 has been used to measure the atmospheric muon rate at two different depths under the sea level: 3.5 km with KM3NeT-ARCA and 2.5 km with KM3NeT-ORCA. Atmospheric muons represent an abundant signal in a neutrino telescope and can be used to test the reliability of the Monte Carlo simulation chain and to study the physics of extensive air showers caused by highly-energetic primary nuclei impinging the Earth's atmosphere. At energies above PeV the contribution from prompt muons, created right after the first interaction in the shower, is expected to become dominant, however its existence has not yet been experimentally confirmed. In this work, data collected with the first detection units of KM3NeT are compared to Monte Carlo simulations based on MUPAGE and CORSIKA codes. The main features of the simulation and reconstruction chains are presented. Additionally, the first results of the simulated signal from the prompt muon component for KM3NeT-ARCA and KM3NeT-ORCA obtained with CORSIKA are discussed.
description: 6 pages, 6 figures, Presented at the 9th Very Large Volume Neutrino Telescope Workshop (VLVnT 2021), Version after first revision by JINST and proofreading
Oscillation and collective behavior in convective flows
Creators: name: Gergely, Attila
name: Paizs, Csaba
name: Tötös, Robert
name: Néda, Zoltán
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Oscillation and collective behavior in convection-driven fluid columns are investigated and discussed in analogy with similar phenomenon observed for the flickering flames of candle bundles. It is shown experimentally that an ascending circular Helium gas column performs an oscillation which is similar in several aspects to the oscillation of diffusion flames. Increasing the nozzle diameter leads to a decrease in the oscillation frequency, while increasing the flow rate results in an increase in this frequency. For helium columns oscillating at nearby frequency and placed close to each other anti-phase synchronization and beating phenomena is observed. A simple toy-model based on elementary hydrodynamics describes the observed oscillations and leads to oscillation frequencies in the right order of magnitude.
description: 10 pages, 10 Figures, Latex
High Pressure studies of the magnetic phase transition in MnSi: revisited
Creators: name: Petrova, Alla E.
name: Krasnorussky, Vladimir N.
name: Lograsso, T. A.
name: Stishov, Sergei M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: New measurements of AC magnetic susceptibility and DC resistivity of a high quality single crystal MnSi were carried out at high pressure making use of helium as a pressure medium. The form of the AC magnetic susceptibility curves at the magnetic phase transition suddenly changes upon helium solidification. This implies strong sensitivity of magnetic properties of MnSi to non hydrostatic stresses and suggests that the early claims on the existence of a tricritical point at the phase transition line are probably a result of misinterpretation of the experimental data. At the same time resistivity behavior at the phase transition does not show such a significant influence of helium solidification. The sharp peak at the temperature derivative of resistivity, signifying the first order nature of the phase transition in MnSi successfully survived helium crystallization and continued the same way to the highest pressure.
description: 4 pages, 6 figures
Self-accelerating solutions in the cascading DGP braneworld
Creators: name: Minamitsuji, Masato
Publisher: name: arXiv
Year: 2008
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The self-accelerating branch of the Dvali-Gabadadze-Porrati (DGP) five-dimensional braneworld has provided a compelling model for the current cosmic acceleration. Recent observations, however, have not favored it so much. We discuss the solutions which contain a de Sitter 3-brane in the cascading DGP braneworld model, which is a kind of higher-dimensional generalizations of the DGP model,where a $p$-dimensional brane is placed on a $(p+1)$-dimensional one and the $p$-brane action contains the $(p+1)$-dimensional induced scalar curvature term. In the simplest six-dimensional model, we derive the solutions. Our solutions can be classified into two branches, which reduce to the self-accelerating and normal solutions in the limit of the original five-dimensional DGP model. In the presence of the six-dimensional bulk gravity, the `normal' branch provides a new self-accelerating solution. The expansion rate of this new branch is generically lower than that of the original one, which may alleviate the fine-tuning problem.
description: 4 pages, critical changes
Quantum Traces in Quantum Teichmüller Theory
Creators: name: Hiatt, Chris
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Algebra (math.QA)
subject: FOS: Mathematics

description: We prove that for the torus with one hole and p greater than or equal to 1 punctures and the sphere with four holes there is a family of quantum trace functions in the quantum Teichmüller space, analog to the non-quantum trace functions in Teichmüller space, satisfying the properties proposed by Chekhov and Fock in their paper "Observables in 3D Gravity and Geodesic Algebras."
Electric Penrose process: high-energy acceleration of ionized particles by non-rotating weakly charged black hole
Creators: name: Tursunov, Arman
name: Juraev, Bakhtinur
name: Stuchlík, Zdeněk
name: Kološ, Martin
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In many astrophysical scenarios the charge of the black hole is often neglected due to unrealistically large values of the charge required for the Reissner-Nordström spacetime metric. However, black holes may possess small electric charge due to various selective accretion mechanisms. In this paper we investigate the effect of a small hypothetical electric charge of a Schwarzschild black hole on the ionization of a freely falling neutral particle and subsequent escape of the ionized particle from the black hole. We show that the energy of ionized particle can grow ultra-high and discuss distinguishing signatures of particle acceleration by weakly charged black holes. We also discuss a possible application of the proposed mechanism as an alternative cosmic ray acceleration scenario. In particular we show that the Galactic centre supermassive black hole is capable to act as a PeVatron of protons. The presented mechanism can serve as a simple toy model of a non-rotating compact object acting as a particle accelerator with a potential astrophysical implementations related to the cosmic ray physics and beyond.
description: 8 pages, 4 figures, accepted to Phys. Rev. D
Exact Scale Invariance in Mixing of Binary Candidates in Voting Model
Creators: name: Mori, Shintaro
name: Hisakado, Masato
Publisher: name: arXiv
Year: 2008
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: We introduce a voting model and discuss the scale invariance in the mixing of candidates. The Candidates are classified into two categories $μ\in \{0,1\}$ and are called as `binary' candidates. There are in total $N=N_{0}+N_{1}$ candidates, and voters vote for them one by one. The probability that a candidate gets a vote is proportional to the number of votes. The initial number of votes (`seed') of a candidate $μ$ is set to be $s_μ$. After infinite counts of voting, the probability function of the share of votes of the candidate $μ$ obeys gamma distributions with the shape exponent $s_μ$ in the thermodynamic limit $Z_{0}=N_{1}s_{1}+N_{0}s_{0}\to \infty$. Between the cumulative functions $\{x_μ\}$ of binary candidates, the power-law relation $1-x_{1} \sim (1-x_{0})^α$ with the critical exponent $α=s_{1}/s_{0}$ holds in the region $1-x_{0},1-x_{1}<<1$. In the double scaling limit $(s_{1},s_{0})\to (0,0)$ and $Z_{0} \to \infty$ with $s_{1}/s_{0}=α$ fixed, the relation $1-x_{1}=(1-x_{0})^α$ holds exactly over the entire range $0\le x_{0},x_{1} \le 1$. We study the data on horse races obtained from the Japan Racing Association for the period 1986 to 2006 and confirm scale invariance.
description: 19 pages, 8 figures, 2 tables
title: Front Matter, Table of Contents, Preface, Conference Organization
Creators: name: Gadducci, Fabio
name: Silva, Alexandra
Publisher: name: Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Year: 2021
Subjects: subject: Front Matter
subject: Table of Contents
subject: Preface
subject: Conference Organization
subject: Theory of computation → Models of computation
subject: Theory of computation → Modal and temporal logics
subject: Theory of computation → Algebraic semantics
subject: Theory of computation → Categorical semantics
subject: Theory of computation → Quantum computation theory
subject: Software and its engineering → Context specific languages

description: Front Matter, Table of Contents, Preface, Conference Organization
description: LIPIcs, Vol. 211, 9th Conference on Algebra and Coalgebra in Computer Science (CALCO 2021), pages 0:i-0:x
Fast Sausage Oscillations in Coronal Loops with Fine Structures
Creators: name: Guo, Mingzhe
name: Li, Bo
name: Shi, Mijie
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Fast sausage modes (FSMs) in flare loops have long been invoked to account for rapid quasi-periodic pulsations (QPPs) with periods of order seconds in flare lightcurves. However, most theories of FSMs in solar coronal cylinders assume a perfectly axisymmetric equilibrium, an idealized configuration apparently far from reality. In particular, it remains to examine whether FSMs exist in coronal cylinders with fine structures. Working in the framework of ideal magnetohydrodynamics (MHD), we numerically follow the response to an axisymmetric perturbation of a coronal cylinder for which a considerable number of randomly distributed fine structures are superposed on an axisymmetric background. The parameters for the background component are largely motivated by the recent IRIS identification of a candidate FSM in Fe XXI 1354 Å~observations. We find that the composite cylinder rapidly settles to an oscillatory behavior largely compatible with a canonical trapped FSM. This happens despite that kink-like motions develop in the fine structures. We further synthesize the Fe XXI 1354 Å~emissions, finding that the transverse Alfvén time characterizes the periodicities in the intensity, Doppler shift, and Doppler width signals. Distinct from the case without fine structuring, a non-vanishing Doppler shift is seen even at the apex. We conclude that density-enhanced equilibria need not be strictly axisymmetric to host FSM-like motions in general, and FSMs remain a candidate interpretation for rapid QPPs in solar flares.
description: Accepted for publication in ApJ Letters
Lowest-lying Tetra-Quark Hadrons in Anisotropic Lattice QCD
Creators: name: Loan, Mushtaq
name: Luo, Zhi-Huan
name: Lam, Yu Yiu
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We present a detailed study of lowest-lying $q^{2}\bar{q}^{2}$ hadrons in quenched improved anisotropic lattice QCD. Using the $ππ$ and diquark-antidiquark local and smeared operators, we attempt to isolate the signal for $I(J^{P})=0(0^{+}), 2(0^{+})$ and $1(1^{+})$ states in two flavour QCD. In the chiral limit of light-quark mass region, the lowest scalar $4q$ state is found to have a mass, $m^{I=0}_{4q}=927(12)$ MeV, which is slightly lower than the experimentally observed $f_{0}(980)$. The results from our variational analysis do not indicate a signature of a tetraquark resonance in I=1 and I=2 channels. After the chiral extrapolation the lowest $1(1^{+})$ state is found to have a mass, $m^{I=1}_{4q}=1358(28)$ MeV. We analysed the static $4q$ potential extracted form a tetraquark Wilson loop and illustrated the behaviour of the $4q$ state as a bound state, unbinding at some critical diquark separation. From our analysis we conclude that scalar $4q$ system appears as a two-pion scattering state and that there is no spatially-localised $4q$ state in the light-quark mass region.
description: 9 pages, 10 figures
Learning Style Preference and Its Correlation with Gender
Creators: name: Buowari, Dabota
name: Joe, Andrew
name: Erekosima, Ibi
Publisher: name: Nigerian Medical Journal
Year: 2025

description: Background: Learning styles have been investigated and classified by several scholars. One of such investigations is the Gender of the individual which can affect learning style. This study investigated the difference in the means of learning styles and its correlation with gender among community health officer trainees at the University of Port Harcourt Teaching Hospital, Nigeria.

 

Methodology: This is a correlational descriptive study, and a census was carried out. A structured questionnaire was utilized and a VARK learning style inventory was used.

 

Results: The reliability of the research instrument using the Cronbach alpha method, the VARK learning style questionnaire had a reliability coefficient of .755, for the subscales visual .455, aura .351, read/write, and kinaesthetic .753. With 60 respondents the means were visual 2.633, aura 4.2833, read/write 3.7500, and kinaesthetic 5.1833 while the standard deviation is visual 1.765, aura 2.429, read/write 2.53534, and kinaesthetic 2.88474. Multiple Analysis of Variance (MANOVA) was conducted to assess the means of the four learning styles concerning gender. The F ratios for the univariate analysis show that males and females did not differ across the four learning styles according to VARK (aural, visual, kinaesthetic, and read/write learning styles), significantly i.e. p < 0,05. Precisely the computed F = .032, P >.05, i.e., p = .859, i.e., p = .859 revealed that no statistical difference occurred between males and females with visual learning styles.

 

Conclusion: The study concluded that community health officer trainees possessed different learning styles and most of them used the kinaesthetic learning style. However, the community health officer trainees were significantly different in their responses to the learning style model according to the VARK inventory of learning styles, but no relationship existed between learning style and gender.
description: Nigerian Medical Journal, Vol. 66 No. 1 (2025): January - February
Shock Breakout Emission from a Type Ib/c Supernova: XRT 080109/SN 2008D
Creators: name: Chevalier, Roger A.
name: Fransson, Claes
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The X-ray flash 080109, associated with SN 2008D, can be attributed to the shock breakout emission from a normal Type Ib/c supernova. If the observed emission is interpreted as blackbody emission, the temperature and radiated energy are close to expectations, considering that scattering dominates absorption processes so that spectrum formation occurs deep within the photosphere. The X-ray emission observed at ~10 days is attributed to inverse Compton scattering of photospheric photons with relativistic electrons produced in the interaction of the supernova with the progenitor wind. A simple model for the optical/ultraviolet emission from shock breakout is developed and applied to SN 1987A, SN 1999ex, SN 2008D, and SN 2006aj, all of which have optical emission observed at t~1 day. The emission from the first three can plausibly be attributed to shock breakout emission. The photospheric temperature is most sensitive to the radius of the progenitor star core and the radii in these cases are in line with expectations from stellar evolution. The early optical/ultraviolet observations of SN 2006aj cannot be accommodated by a shock breakout model in a straightforward way.
description: Revised, accepted version
Galois coverings of weakly shod algebras
Creators: name: Meur, Patrick Le
Publisher: name: arXiv
Year: 2008
Subjects: subject: Representation Theory (math.RT)
subject: FOS: Mathematics
subject: 16G10, 16G60, 16G70

description: We investigate the Galois coverings of weakly shod algebras. For a weakly shod algebra not quasi-tilted of canonical type, we establish a correspondence between its Galois coverings and the Galois coverings of its connecting component. As a consequence, we show that a weakly shod algebra is simply connected if and only if its first Hochschild cohomology group vanishes.
description: Some references were added. The proof of Lemma 6.5 was modified
A Call to Action: Insights into Hypertension Prevalence and Management in an Urban Sub-Saharan African Population
Creators: name: Mbah, Teko
name: Lema, Bernadette
name: Rikam, Armand
name: Baning, Jacques
name: Ngon, Serges
name: Kilama, Georgette
name: Ngon, Divine
name: Ngon, Odile
name: Ebango, Fabrice
name: Ebango, Suzanne
name: Egom, Emmanuel
Publisher: name: Nigerian Medical Journal
Year: 2025

description: Background: Hypertension is a global health challenge, with a disproportionate burden in low- and middle-income countries like Cameroon. Urban centers, such as Yaoundé, face increasing prevalence driven by rapid urbanization and healthcare disparities. The study objective is to assess hypertension prevalence, associated risk factors, and barriers to effective management in an urban Cameroonian population.

 

Methodology: A cross-sectional study was conducted in 2024 as part of the HEAVEN-CIEL Hypertension Awareness Campaign. Data from 181 adults were collected through structured questionnaires and physical assessments, including blood pressure measurements. Associations with demographic, socioeconomic, and lifestyle factors were analyzed using chi-square tests and logistic regression.

 

Results: Hypertension prevalence was 59.67%, with rates peaking at 75.56% among individuals aged 46–60 years (p = 0.0019). Medium-income participants showed the highest prevalence at 75.56% (p = 0.043). Obesity (p = 0.0024) and high-fat diets (p = 0.0212) were significant risk factors. Alarmingly, 87.04% of hypertensive individuals were untreated, highlighting gaps in medication access and adherence.

 

Conclusion: Hypertension in Yaoundé represents a major public health concern, driven by age, socioeconomic disparities, and unhealthy lifestyle factors. The low treatment rates reflect systemic healthcare barriers. Comprehensive, culturally sensitive interventions are urgently needed to improve awareness, prevention, and management. Future research should focus on the longitudinal impacts of targeted public health strategies.
description: Nigerian Medical Journal, Vol. 66 No. 1 (2025): January - February
QED factorization of two-body non-leptonic and semi-leptonic $B$ to charm decays
Creators: name: Beneke, Martin
name: Böer, Philipp
name: Finauri, Gael
name: Vos, K. Keri
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The QCD$\times$QED factorization is studied for two-body non-leptonic and semi-leptonic $B$ decays with heavy-light final states. These non-leptonic decays, like $\bar{B}^0_{(s)}\to D^+_{(s)} π^-$ and $\bar{B}_d^0 \to D^+ K^-$, are among the theoretically cleanest non-leptonic decays as penguin loops do not contribute and colour-suppressed tree amplitudes are suppressed in the heavy-quark limit or even completely absent. Advancing the theoretical calculations of such decays requires therefore also a careful analysis of QED effects. Including QED effects does not alter the general structure of factorization which is analogous for both semi-leptonic and non-leptonic decays. For the latter, we express our result as a correction of the tree amplitude coefficient $a_1$. At the amplitude level, we find QED effects at the sub-percent level, which is of the same order as the QCD uncertainty. We discuss the phenomenological implications of adding QED effects in light of discrepancies observed between theory and experimental data, for ratios of non-leptonic over semi-leptonic decay rates. At the level of the rate, ultrasoft photon effects can produce a correction up to a few percent, requiring a careful treatment of such effects in the experimental analyses.
description: 23 pages, 2 figures
Confidence Sets Based on Penalized Maximum Likelihood Estimators in Gaussian Regression
Creators: name: Pötscher, Benedikt M.
name: Schneider, Ulrike
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistics Theory (math.ST)
subject: Methodology (stat.ME)
subject: Machine Learning (stat.ML)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences

description: Confidence intervals based on penalized maximum likelihood estimators such as the LASSO, adaptive LASSO, and hard-thresholding are analyzed. In the known-variance case, the finite-sample coverage properties of such intervals are determined and it is shown that symmetric intervals are the shortest. The length of the shortest intervals based on the hard-thresholding estimator is larger than the length of the shortest interval based on the adaptive LASSO, which is larger than the length of the shortest interval based on the LASSO, which in turn is larger than the standard interval based on the maximum likelihood estimator. In the case where the penalized estimators are tuned to possess the `sparsity property', the intervals based on these estimators are larger than the standard interval by an order of magnitude. Furthermore, a simple asymptotic confidence interval construction in the `sparse' case, that also applies to the smoothly clipped absolute deviation estimator, is discussed. The results for the known-variance case are shown to carry over to the unknown-variance case in an appropriate asymptotic sense.
description: second revision: new title, some comments added, proofs moved to appendix
Bilateral Optic Atrophy and Epiretinal Membranes: An Atypical Presentation of Ocular Tuberculosis
Creators: name: Babalola, Yewande
Publisher: name: Nigerian Medical Journal
Year: 2025

description: A 15-year-old boy presented himself to the retina clinic with a six-year history of poor vision in both eyes. Ocular symptoms started with deterioration in the vision of both eyes associated with ocular pain. There was no history of antecedent trauma, headaches, seizures, or loss of consciousness. The general and systemic examinations were normal. On ocular examination, the corrected visual acuity was 6/24 and 6/6 in the right and left eyes, respectively. The anterior segment examination was normal except for a relative afferent pupillary defect in the right eye. Examination of the posterior segment revealed bilateral optic atrophy worse in the right eye and cup disc ratios of 0.3 bilaterally. The vessels were within normal limits with epiretinal membranes in both eyes. Yellowish chorioretinal lesions were present temporal to the disc in both eyes. There was a positive history of tuberculosis in the father and brother. A diagnosis of bilateral optic atrophy and epiretinal membranes secondary to presumed ocular tuberculosis was made.
description: Nigerian Medical Journal, Vol. 66 No. 1 (2025): January - February
Root polytopes and growth series of root lattices
Creators: name: Ardila, Federico
name: Beck, Matthias
name: Hosten, Serkan
name: Pfeifle, Julian
name: Seashore, Kim
Publisher: name: arXiv
Year: 2008
Subjects: subject: Combinatorics (math.CO)
subject: Commutative Algebra (math.AC)
subject: FOS: Mathematics
subject: 05A15, 05E15, 11H06, 13D40, 14M25, 52B20, 52C07

description: The convex hull of the roots of a classical root lattice is called a root polytope. We determine explicit unimodular triangulations of the boundaries of the root polytopes associated to the root lattices A_n, C_n, and D_n, and compute their f-and h-vectors. This leads us to recover formulae for the growth series of these root lattices, which were first conjectured by Conway-Mallows-Sloane and Baake-Grimm and proved by Conway-Sloane and Bacher-de la Harpe-Venkov.
description: 17 pages, 3 figures
Emergent Gravity and Noncommutative Branes from Yang-Mills Matrix Models
Creators: name: Steinacker, Harold
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The framework of emergent gravity arising from Yang-Mills matrix models is developed further, for general noncommutative branes embedded in R^D. The effective metric on the brane turns out to have a universal form reminiscent of the open string metric, depending on the dynamical Poisson structure and the embedding metric in R^D. A covariant form of the tree-level equations of motion is derived, and the Newtonian limit is discussed. This points to the necessity of branes in higher dimensions. The quantization is discussed qualitatively, which singles out the IKKT model as a prime candidate for a quantum theory of gravity coupled to matter. The Planck scale is then identified with the scale of N=4 SUSY breaking. A mechanism for avoiding the cosmological constant problem is exhibited.
description: 45 pages. V2: typos corrected, reference added. V3: discussion and references added. V4: derivation of Ward identity fixed